The absorbent product

 

(57) Abstract:

The invention relates to the production of absorbent foam materials for use as absorbent articles, in particular diapers that absorb and hold water fluids in the body. Such foam materials include hydrophilic open cell structure, preferably obtained by emulsion polymerization, water-in-oil high internal phase. The oil phase contains a glassy monomer based on styrene, water-insoluble kouchkovsky comonomer and a bifunctional crosslinking agent. Such foam materials have a pore volume or porosity of the order of from 12 to 100 ml/g and specific surface capillary suction of the order of from 0.5 to 5.0 m2/, These materials also possess resistance to deflection of compression such that the limiting pressure of 5.1 kPa produces after 15 min exposure to the deformation of the order of 5% to 95% compression, when the material is saturated at 37oTo its free absorbent capacity of artificial urine. 2 C. and 8 C.p. f-crystals, 1 tab., 4 Il.

The invention relates to a flexible microporous open cellular polymeric foam material having absorbent who in their products, absorbent body fluids, for example urine, such as diapers, underwear for adults suffering from incontinence, sleeping pads, liners for underpants, internal tapes for hats, Shoe insoles, etc.

Development of materials with a high absorbent capacity and structures for use in diapers, products for menstruation, bandages, etc. is the subject of increased commercial interest. Initially these products were based on different tissues or cotton fibres to ensure namely. Further progress in the field of absorbent materials and structures was accompanied by the development of various gaskets from air laid pulp, which generally absorb in 5-6 times their own weight of aqueous body fluids, for example urine. Later the use of absorbent gelling materials, such as polyacrylates, in combination with cellulose fibers significantly increased absorbent capacity of absorbent products such as diapers, and allows the production of relatively thin diapers, which are sold at the present time. However, even with these improvements, the search for the best absorbent material and the sponge-like materials, which in its broad aspect can be considered as open cell foam, will be quite suitable for absorbent structures and articles. So, for example, and natural sponge, synthetic cellulose sponge was used to wipe water and other liquids from time immemorial. However, upon closer examination it will be obvious that these sponges are not suitable, in particular, for high performance products, absorbent body fluid currently in use. So, for example, absorbent products are used primarily in the dry state. It is well known that many dry sponge materials are sufficiently rigid and unpleasant when in contact with the skin, and therefore would not be suitable for use in diapers and other products for those suffering from incontinence. In addition, many of the normal spongy materials have different cell sizes and partially or completely closed cells, which prevent the absorption and retention of liquid sponge. And finally, while conventional porous materials can absorb significant quantities of aqueous liquids, however, they also secrete or release the absorbed liquid when exposed to the situations that when the absorbent structure is used in terms of the action of pressure, for example when a child in the diaper sits down.

In addition to the usual "sponges" literature and commercial practice filled with descriptions of different types of polymer foams, which can absorb different fluids for different purposes. It is also known the use of certain types of polymeric foam materials as elements of absorbent products such as diapers and products for menstruation. For example, in U.S. patent N 4029100 describes a form-retaining the diaper, which can use the foam element in the perineal part of its absorbent pad for high flexibility in the wet state.

Some types of foam materials have been described as suitable for absorbent products for the actual suction absorption and/or retention of aqueous body fluids. For example, in U.S. patent N 3563243 describes the absorbent pad for diaper and so forth, in which the absorbent material is a hydrophilic foam sheet made of hydrophilic polymers. These foam sheets, you can say, are formed by mixing polyoxyethyleneglycol with India is ut be used in diapers or products for menstruation. Such porous polymers include the reaction products of at least one epoxy resin and aminoborane poly(spontoonie). In U.S. patent N 4740528 describes an absorbent composite structure, such as diapers, feminine hygiene products, etc. containing porous absorbent composition made with a specific type ultra-absorbent reticulated polyurethane foam.

Known absorbent article suitable for absorbing and retaining aqueous body fluids containing relatively impermeable to fluid back sheet and a polymeric foam material located between the rear sheet and place of receipt of fluid from the user device, the polymeric foam material obtained by the emulsion polymerization in the system "water-in-oil and oil phase of the emulsion contains a glassy monomer based on styrene, essentially water-insoluble kouchkovsky comonomer, and a bifunctional crosslinking agent (EP N 0068830).

From this patent it is known absorbent article suitable for absorbing and retaining aqueous body fluids containing relatively impermeable to fluid back sheet, and a polymer foam maturemature known to use different types of polymer foams as elements of absorbent articles for body fluids, there is a continuing need to identify additional absorbent foam materials having an optimal combination of parameters and characteristics that make such foam is particularly useful commercially available absorbent products such as diapers. It is now established that the optimized absorbing foam for body fluids and especially foam, designed for use in diapers and products for adults suffering from incontinence, should have the following characteristics:

a) flexibility and preferably a recovery after compression for comfort and performance,

b) an acceptable rate of fluid intake, so that the foam can quickly adopt and absorb the strong streams of urine or other liquids;

C) relatively good characteristics of absorption and distribution of liquid to foam transported absorbed urine or other liquid from the place of receipt on her side of the unused balance of the foam structure, in order to take the next abundant flow of fluids;

d) a relatively large total capacity at relatively high capacity fluid under load, i.e. tastiest and contained a thin soft material;

(f) relatively greater compatibility absorb body fluids than in other components of the absorbent product, resulting in a foamy material can allocate (allocate) the liquid from these other components and to retain such liquid stored in the foamy structure.

The basis of the invention is to create an absorbent article having the above properties.

It will be obvious that the absorbent foam having the above characteristics, will have such characteristics as the reception, transport and storage of fluids that are required for use in high performance absorbent products. Optimized foam will preferably be soft to the touch. Of course, absorbent foam intended for use in contact with or in close proximity with the skin, should not cause damage or irritation to the skin and should not expose the user to exposure to toxic chemicals. Because they are intended for use in disposable articles such as diapers, such preferred optimized foam should be otdyh waste as, for example, on the basis of landfill, incineration and/or composting.

For manufacturers of absorbent articles is obviously optimized absorbent foam materials of the type indicated above will represent significant progress in the industry. Absorbent articles containing such foams will have the desired integrity in the wet state, will provide the necessary seal for the entire period you wear the product, they will not lose its shape in the process of wearing and will provide the desired dryness of the skin.

Absorbent articles containing such foam structures will also be easily manufactured on an industrial basis. For example, the core of the diaper may simply be stamped from a continuous foam sheet and can be made to have greater integrity and uniformity than air laid absorbent cores. In addition, such foam can be molded to any desired shape or even be formed in a single integral structure-type diaper or underpants. Or, such foam materials can be combined, for example, be mixed with other components conventional absorbent structures.

<, prigodnogo to absorb and retain aqueous body fluids containing relatively impermeable to fluid back sheet and a polymeric foam material located between the rear sheet and place of receipt of fluid from the user device, the polymeric foam material obtained by the emulsion polymerization in the system "water-in-oil and oil phase of the emulsion contains a glassy monomer based on styrene, essentially water-insoluble kouchkovsky comonomer, and a bifunctional crosslinking agent, which according to the invention the polymeric foam material has a magnitude of bending at least one cycle when saturation artificial urine at 37oC, and washed and dried the state has a hydrophilic flexible structure of interconnected open cells, containing a sufficient amount of residual hydrophilizing agent containing no irritating surfactant to convert the surface of the above structure in the hydrophilic, and this structure is used as the adsorbent pore volume from 12 to 100 ml/g, specific surface area when determining capillary suction from 0.5 to 5.0 is Astia deformation of the compression component 5 to 95% volume of the foam structure when it is saturated at 37oC to its free absorbent capacity of the artificial urine having a surface tension (655) Dyne/cm, while the oil phase contains from 3 to 41 wt.% essentially water-insoluble monofunctional glassy monomer based on styrene, from 27 to 73 wt.% monofunctional kauchukopodobnoe of co monomer selected from the group comprising 2-ethyl hexyl acrylate, butyl acrylate, butadiene, isoprene and a combination of all of these comonomers, and from 8 to 30 wt.% bifunctional forming a cross-link agent selected from the group comprising divinylbenzene, divinylsulfide, diallylphthalate, one or more diacrylate acid esters of a polyhydric alcohol or a mixture thereof.

Preferably, upon receipt of a polymeric foam material, the molecular ratio of monofunctional glassy monomer to koucouloutou the co monomer in the oil phase ranged from 1:25 to 1.5:1, and the oil phase consisted of from 2 to 33 wt.% emulsifier component, soluble and suitable for forming a stable emulsion of water-in-oil", and from 0.2 to 40 wt.% the water-soluble electrolyte, and the massive aspect] the buffer of net material was hydrophilic to such an extent, she shows the adhesion tension of from 15 to 65 Dyne/cm, when it absorbs artificial urine having a surface tension 655 Dean/see

It is advisable to oil phase containing an emulsifier selected from the group comprising ether of sorbitol and fatty acids, ether polyglycerol and fatty acid esters of polyoxyethylene and fatty acids, and combinations thereof, and the aqueous phase consisted of one or more water soluble salts of alkali metals or alkaline earth metals.

It is desirable that the hydrophilic flexible structure of the porous polymer material in the place of their use as absorbent had a density in the dry state of from 0.01 to 0.08 g/cm2the cell size of 5 to 100 μm, the recovery of deflection compression such that after compression with a duration of one minute structure recovers within one minute, at least 85% of its original thickness when it is being in a dry state or when the saturation patterns to free absorbent capacity of the artificial urine having a surface tension 655 Dyne/cm at 37oC, followed by compression with a duration of one minute structure recovers within one minute less than the greater extent, 12 ml of synthetic urine per gram of dry polymer foam material, the absorbent capacity with synthetic urine under the action of the limiting pressure of 5.1 kPa for 15 minutes at 37oC at least 5% of its equilibrium free absorbent capacity, speed vertical absorption at 37oC such that the artificial urine absorbed by the vertical length of the polymer foam material, equal to 5 cm in no more than 30 minutes, and the absorbent capacity of the vertical absorption of at least 10 ml of synthetic urine per gram of polymeric foam material during the height of the vertical absorption 11,4 see

It is possible that the polymer foam material essentially does not contain polar functional groups in its polymer structure and contains from 0.1 to 10 wt. % residual hydrophilizing agent selected from not irritate the skin surface-active substances and logogeriatrics inorganic salts.

Useful if the product is in addition contained essentially permeable to fluid top sheet, and the polymer foam material is an absorbent core located between the relatively short-Technik contained an additional component of cellulose fibers and/or particles or fibers of polymeric gelling agents either he had a multilayered structure with a top layer containing fibers of wood pulp or reinforced twisted twisted cellulose fibers, and up to 10 wt. % of particles of polymeric gelling agent, and with the bottom layer containing the foaming material.

Preferably, the product was made in the form of a disposable diaper, in which the top sheet has the same length with one surface of the absorbent core, the back sheet has the same length on the other surface of the core, the opposite surface is covered with a top plate, and has a width larger than that of the core, to form the back sheet side edge portions protruding beyond the core, the absorbent core has the shape of an hourglass. This task, according to another aspect of the invention, is solved by means of absorbent articles suitable for absorbing and retaining aqueous body fluids containing relatively impermeable to fluid back sheet, and a polymer foam material located between the rear sheet and place of receipt of fluid from the user product in which according to the invention the polymeric foam material is sgetn to absorb liquids, the polymeric foam material has a dry hydrophilic flexible non-hydrolyzed structure of mutually connected open cells having a specific surface capillary suction from 0.5 to 5.0 m2/g and containing additionally includes from 0.5 to 20 wt.% residual water-insoluble emulsifier and 0.1 to 7 wt.% toxicologically acceptable hygroscopic hydrated salt, the structure is in its compressed state, the water content of 4 to 15 wt.% polymeric foam material and a dry density of from 0.08 to 0.3 g/cm2and in its expanded state pore volume from 12 to 100 ml/g, the resistance to deflection of compression such that the limiting pressure of 5.1 kPa creates after 15 minutes exposure to the deformation of the compression ratio from 5% to 95% of the volume of the foam structure when it is saturated at 37oC to its free absorbent capacity of the artificial urine having a surface tension (655) Dyne/cm and a density in the dry free state when saturated to its free absorbent capacity of the artificial urine, from 9 to 28% from its specific density of dry compressed state. Preferably, the product is in addition contained essentially permeable to the nom between the relatively impermeable to fluid rear sheet and being permeable to fluid top sheet, the absorbent core contained an additional component of cellulose fibers and/or particles or fibers of polymeric gelling agents, or had a multilayered structure with a top layer containing fibers of wood pulp or reinforced twisted twisted cellulose fiber and up to 10 wt.% particles of polymeric gelling agent, and with the bottom layer containing the polymer foam material.

It is advisable that the product was made in the form of a disposable diaper, in which the top sheet has the same length with one surface of the absorbent core, the back sheet has the same length on the other surface of the core, the opposite surface is covered with a top plate, and has a width larger than that of the core, to form the back sheet side edge portions protruding beyond the core, the absorbent core has the shape of an hourglass.

The invention will be clear from the further detailed description of the invention, illustrated by drawings, in which:

in Fig. 1 shows a micrograph then typical absorbent foam MDF according to the present invention;

in Fig. 2 is a view partly Villa is the shadow as a component in the shape of an hourglass storing/distributing the liquid in the absorbent core of the diaper, having a two-layer construction;

in Fig. 3 - the image cut-out a form-retaining articles, such as disposable training pants, which are used absorbent foam MDF structure according to the present invention as an absorbent core;

in Fig. 4 - the image of the disassembled components of the diaper with double-layer core having a clamping liquid layer in the shape of an hourglass, covering the absorbent foam storing/distributing liquid layer having a modified form of the hourglass.

As noted, the present invention is based on the use of a certain type-specific resulting polymer foam material is used as the absorbent material for the incoming aqueous body fluids, e.g. urine. These polymeric foam absorbent materials can thus be used as or as part of the absorbent cores of absorbent articles, such as diapers, short underpants for those suffering from incontinence or prekladom, training pants, etc.

The polymer foam can generally be characterized as patterns, which are obtained, to which in the form of bubbles in containing the polymerized monomer liquid, accompanied by polymerization able to polymerization of the monomers in monoaminoxidase liquid surrounding the bubbles. The resulting polymerized dispersion may be in the form of a hardened porous structure consisting of cells, partition or wall which contain solid polymerized material. The boxes contain gas, relatively free of monomer, or a liquid, relatively free of the monomer before the polymerization of the formed bubbles in the liquid dispersion.

As will be described in more detail below, the preferred polymeric foam materials suitable for use as absorbents in the present invention are those which are prepared by polymerization of a specific type emulsion of water in oil. Such an emulsion is formed from a relatively small number containing polymerizable monomer oil phase and a relatively greater magnitude is relatively devoid of the monomer aqueous phase. Relatively free from monomer previewdata "dispersed water phase forms, therefore, dispersed bubbles surrounded by a continuous containing the polymerized monomer of the oil phase. Subsequent polymerize in the foamy structure, the resultant polymerization may be removed by pressing and/or drying of the foam.

Polymer foam comprising the preferred foam prepared from emulsions of water in oil can be relatively closed mesh or relatively open mesh, depending on, whether filled the walls of the cells, because the cell boundaries and are they made of polymeric material and/or the extent to which the walls of the cells are filled or consist of a polymer material. Polymeric foam materials used in absorbent products and structures according to the present invention are those which have a relatively open cells in that individual cell foam in large part are not completely isolated from each other by a polymeric material of the walls of the cells. Thus, the cells in the foam structures with open cells have intercellular openings or "Windows", which is large enough to ensure the rapid transfer of fluid from one cell to another within the foam structure. In structures with essentially open cells, which can be used in the present invention, the foam typically has a mesh design with individual is ADI) polymer material, components branched mesh open foam structure can be called "posts", a foam with open cells, with a typical rack-type structure, shown for example in the micrograph shown in Fig. 1. For use in the present invention, the foam material is "open cells (open)" if at least 80% of the cells in the foam structure is in hydraulic communication with at least one neighboring cell. Or foamy material may be considered essentially open if it contains the available pore volume, as will be described but is lower in excess of the minimum value for this parameter, as will be described below.

In addition to the open cell polymer foam absorbents according to the present invention are hydrophilic in character. Foam here should be sufficiently hydrophilic to provide a water absorption of body fluids in quantities which will be given below. As will be discussed below in respect of the preferred types of foams and methods for their production, the inner surface of the pen can be made hydrophilic, due to the particular monomers selected to receive polimernymi or by choosing operations after curing processing, which can serve to modify the surface energy of the material forming the foam structure.

The degree of hydrophilicity" polymer foam structures as those used in the present invention, is determined by the "adhesion tension", which appears when the contact of the foam with absorbable experienced by the fluid. Adhesion voltage is determined by the formula;

AT = cos,

where AT is the adhesion tension, Dyne/cm;

- the surface tension of the test liquid absorbed by the foam material, Dyne/cm;

the contact angle in degrees between the surface of the polymer foam material and the vector tangent to the test fluid at the point of contact of the test liquid with the surface of the foaming material.

For any hydrophilic foam material of the adhesion voltage that is manifested foam, can be determined experimentally using the procedure, which involves measuring the absorbed weight of the test liquid, such as artificial urine, frothy sample with a known size and specific surface capillary suction. This procedure is described in more detail below in the section "Methods of test is tofilename to such an extent, what are the adhesion tension of the order of from 15 to 65 Dyne/cm, more preferably from 20 to 65 Dyne/cm, which is determined by the absorption capillary artificial urine having a surface tension 655 Dean/see

Besides that used in the present invention the polymeric foam material is "open" and "hydrophilic", they should also have a special set of structural and mechanical properties, attributes or characteristics. It was found that the polymer foam having such selected structural and mechanical properties, attributes and/or characteristics will, as a consequence, to have the ability, for example, to transport the liquid, making such foams are particularly suitable and suitable as absorbents for aqueous body fluids.

1) Structural properties.

Specific partly interrelated and interdependent structural properties were identified as being essential for the implementation of the foam absorbents, especially suitable for absorbing aqueous body fluids. It should be borne in mind that foam materials according to the present invention may have structural her the aqueous fluid of the body. For example, during manufacture, shipping, storage, etc. of the foam can have values of pore volume, specific surface area, density and/or cell size outside the range below for these parameters. However, such foam absorbent structure will nevertheless continue to be within the scope of the scope of patent claims of the present invention, if they later undergo physical or rheological changes, with the result that they then have the desired size below for these structural properties, at least at some point during the subsequent contact between the absorbent structure and absorbed by its water liquid body. Such a significant and preferred structural properties of the foam absorbents here can be summarized as follows:

A) pore Volume.

Pore volume or porosity is a measure of the amount of holes or cells in the porous foam structure per unit mass of solid material (polymer structure plus any residual solids, which form the foam structure. The pore volume may be important in influencing some of the characteristics and mechanical characteristics altocamet pins for aqueous body fluids, the degree and speed distribution of the fluid within the structure due to capillary wicking of the absorbed aqueous fluids from one part of the absorbent foam in another, and the characteristics of flexibility and deflection compression are given.

The pore volume may be determined by any suitable experimental method, which would provide an accurate indication of the actual volume of the pore structure. Such experimental methods usually involve the measurement of volume and/or weight of the test liquid, which can be entered in the foamy structure and which, therefore, represents the volume occupied by the open cells of the foam. For this reason, the parameter pore volume for foams according to the invention can also be named as the available pore volume.

One of the most common methods of experimental determination of the available pore volume includes a liquid with low surface tension, for example, isopropyl alcohol, foamy structure with its outer side. The procedure definition, the available pore volume, use isopropyl alcohol below under "test Methods". It should be borne in mind, however, that to determine the available on berousek pins, used here, it is possible to influence and control it by adjusting some parameters of the foam composition and processing. For example, for the preferred pen-based emulsions MDF according to the invention such parameters affecting the pore volume may include the ratio of water and oil in the emulsion MDF, the type and amount of the electrolyte aqueous phase, the type and amount of emulsifier in the oil phase, the compression of the foam after its polymerization and the degree of recovery of the cured foam structure after such compression operations.

Foam materials according to the present invention will typically have a pore volume of from 12 to 100 ml/g; more preferably from 20 to 70 ml/g, and most preferably about 25 to 50 ml/year is Assumed that such ranges of pore volume provide a comprehensive definition of theoretical pore volume for foam, covered by the present invention. Thus, if any experimental method, according to which it can reasonably be assumed receipt of dimensions approximating theoretical pore volume, provides a value within the above ranges, then any foamy material">

C) Specific surface capillary suction.

Another important structural characteristic of foam materials according to the invention is defined specific surface capillary suction. The specific surface capillary suction is generally a measure characterizing the test fluid - accessible surface area of the polymer lattice, forming the foam, per unit mass of loose foamy material (polymer structural material plus solid residual material). The specific surface capillary suction is defined as the size (i.e. diameter) mesh nodes in the foam, and size (length, width, thickness) of the uprights forming such wire mesh nodes. Thus, the specific surface capillary suction is a way to determine the total amount of the solid surface formed by the foam lattice, in the sense that the surface is involved in the absorption.

The specific surface capillary suction open foam structure, as, for example, absorbent foam, according to the invention, is a parameter foam affecting the capillarity (capillary action or suction), the solidity of the foam. It was us who stranded sufficient capillarity, in order to provide acceptable fluid retention, while allowing for a certain capillary flow of liquid in the foam structure. Regulation of specific surface capillary suction, and the regulation of hydrophilicity of the surfaces of the foamed polymer is, therefore, a means for providing the required degree of capillarity for the absorbent foams of the present invention. Foam with a relatively high specific area of the capillary suction provide a very desirable combination of high capacity and low density) and high capillarity. High specific area is a consequence of the thickness of the uprights, the components of the foam structure.

The specific surface capillary suction foam absorbents according to the invention is subjected to influence and control by regulating many of the same properties and processes that affect the pore volume of the foam. For pen-based emulsion MDF parameters of the composition include the ratio of water in oil emulsion MDF, as well as the type and amount of monomers, emulsifiers and electrolytes used in the emulsion MDF. The processing parameters that affect the specific surface capillary suction, include saving the th any given foam material, considered for use in the present invention, can and will usually be determined by the procedure, including the principle of capillary suction. In this procedure, the specific surface capillary suction is determined by measuring the amount absorbed by the capillaries with low surface tension liquids (e.g. ethanol), located in the foamy sample of known mass and dimensions. A detailed description of this procedure is to determine the specific surface of the foam using the method of capillary suction below under "test Methods". To determine the specific surface capillary suction may be used any suitable alternative method.

Open porous absorbent foams suitable for use in the present invention are foams that are prepared to have certain characteristics specific surface capillary suction. In particular, the foam according to the invention will have a specific surface capillary suction, ranging from 0.5 to 5.0 m2/g, preferably from 0.75 to 4.5 m2/g and more preferably from 1.0 to 4.0 m2/, Was discovered, is to be an especially desirable balance of properties absorbent ability the retention of fluids and the absorption or distribution of aqueous body fluids, for example urine.

C) Additional or alternative structural features.

Two additional structural features of absorbent foams according to the invention, which is correlated with the pore volume and specific surface capillary suction, and which can be used as an additional or alternative way of determining the foam according to the invention are the density and the average size or diameter of the cells that form the foam. Each of these two complementary/alternative structural characteristics are described as follows:

1) the density of the foam.

The density of the foam materials according to the invention, as pore volume and specific surface capillary suction, can influence a number of performance characteristics and mechanical characteristics of the absorbent foams according to the invention. This includes absorbent capacity for aqueous body fluids, the degree and speed distribution of the fluid in the foam and characteristics of flexibility and deflection of the compression of the foam. It is also important that the density of the foam absorbent structures according to the invention can determine imetr volume of foam in the air is calculated here on a dry basis. Thus, the amount of absorbed aqueous liquid, for example the residual fluid that may remain in the foam, for example, after polymerization, emulsion MDF, washing and/or hydrophilization, is not taken into account in the calculation and expression of foam density. However, the density of the foam, as defined here, includes the residual solid material, for example, the electrolyte emulsifier, Hydrophilidae agents, etc. in the cured foam. This residual material can in fact contribute to a significant mass of foam material.

Any suitable gravimetric method provides determination of the mass of solid foam material per unit volume of the foam structures can be used to measure the density of the foam. For example, the gravimetric method ASTM described in more detail below under "test Methods", is one of the ways that can be used to determine the density. For those cases when the procedure for preparation of the foam sample (drying, aging, pre-bending and so on) can accidentally change the resulting density measurement, you can use other tests to determine density. Such other ways Suprematist material. This type of method of determining the density may be suitable for characteristics of the foams with very low density, as, for example, foams according to the invention, in which the dry density approximates the inverse of the concept of pore volume of the foam. (see Catarci, "Absorption capacity", textile Science and Technology, I. 7, 1985, page 41). As for pore volume and specific surface capillary suction, the ranges for the density of the foam below are exhaustive, i.e., is recognized to cover the value of the density, which can be determined using any suitable test method.

Foam absorbents according to the present invention will preferably have a density value on a dry basis, about 0.01 to 0.08 g/cm3preferably of the order of 0.014 to 0.05 g/cm3and more preferably from 0.02 to 0.04 g/cm3when such foam absorbents meet with absorbable liquid water. The density of the foam materials can be adjusted within the above ranges by regulating many of the same parameters of the composition and process described above for controlling the volume of the pores. The density of the absorbent foam structures ZDNet relatively higher density or lower density, than other portions or areas.

2. The size of the cell.

Other alternative or additional structural characteristic of absorbent foams according to the invention, which is essentially a set, but which may be useful when determining the preferred foam materials of the present invention is the cell size. Foam cells, and particularly cells formed by the polymerization containing monomer oil phase surrounding the bubbles are relatively free from monomer aqueous phase, will often be essentially spherical in shape. The size or "diameter" of such essentially spherical cells is, therefore, another commonly used parameter to harakterizovali pins in General, and to describe some of the preferred absorbent foams of this type, which are used in the present invention. Because cells in a given sample of polymer foam will not necessarily be about the same size, the average cell size, i.e., average cell diameter, will often be specified.

As the foam density, the specific surface capillary suction and pore volume, cell size is a parameter of the foam, which can Otsego invention. Since the cell size is a factor, together with the specific surface capillary suction, pore volume and hydrophilic foam determining the capillarity of the foam, the cell size is a parameter of the structure of the foam directly influencing absorptive capacity and internal properties of capillary wicking of the liquid foam absorbents here. The cell size can also affect the mechanical properties of the foam absorbents according to the invention, including characteristics as flexibility and resistance to deflection and recovery of deflection compression.

There are several ways to determine the average cell size in the foam. These methods include mercury ways of determining the porosity, which are well known in the art. The most common way, however, to determine the cell size in the foam is easy photographic measurement of the foam sample. In Fig. 1 of the drawings, for example, presents a micrograph of the fracture surface typical absorbent structure of the foam MDF of the present invention. The micrograph superimposed scale representing a size of 10 μm. This scale can be used to determine the average cell size of paternoster commonly used tool which can be used to determine the average cell size of the foam structures according to the invention. This method is described in more detail in Edwards and others, U.S. patent N 4788225, issued November 29, 1988, This patent is provided here for information.

As a direct photographic measurement, foam, suitable as absorbents for aqueous body fluids in accordance with the present invention, will preferably have an average cell size, ranging from 5 to 100 μm. More preferably the cell size varies from 10 to 90 μm. Most preferably the cell size is on the order of from 15 to 80 microns.

The size or diameter of the cells in the foamy absorbents can be influenced or controlled by the same parameter changes of composition and processing, which affect the specific surface capillary suction and the available pore volume. For the preferred pen-based MDF here are mainly those factors that determine the size of the "bubbles" of the aqueous phase in the matter preceding emulsion MDF, polymer foam structures. Thus, the cell size can be changed by regulating soo is Ulzii MDF. The cell size can also be changed by simple compression of solid foam structures after their preparation.

As noted above, the cell sizes in absorbent foams according to the present invention will be generally unequal, resulting in an average cell size for any given foam sample or zone in the foamy sample can and should be calculated. Of course, you can use absorbent foam having distinguishable discrete zones with relatively larger or relatively smaller cell size.

II) Mechanical characteristics.

Absorbent foam having a suitable polymer composition and structural features described above, will have mechanical properties, such as resistance or resistance to deflection compression, flexibility, recovery deflection compression, integrity, softness, etc. that make such foam suitable for use as absorbent structures in absorbent articles such as disposable diapers. Among the above-mentioned structural constraints, however, it is possible to select certain combinations of parameters and/or certain ways of making foam and conditions of the Asti interconnected mechanical properties, identified as contributing to the realization of absorbent foams are particularly suitable for use in absorbent products to help those suffering from incontinence can be summarized as follows:

A) resistance to the deflection of the compression.

The most important mechanical property of polymer foams according to the present invention is the durability of foam absorbent material, which is defined as its resistance to deflection compression. The resistance to deflection compression, exercise foam absorbents according to the invention is a function of the modulus of elasticity of the polymer and the size of the "pillars" that form the foam grille. The modulus of elasticity of the racks, in turn, is determined by (a) a polymer composition racks and b) the degree to which the rack can be plasticized residual material, for example, an emulsifier synthesized aqueous phase or the subsequent addition hydrophilizing agent remaining in the foam structure after processing.

To be suitable as absorbent structures in absorbent articles such as diapers, absorbent foam materials according to the present invention must have an appropriate resistance to Deactive absorbed in and holds the liquid state. Foam, not possessing sufficient strength from the point of view of resistance to deflection compression, may be able to absorb and store a sufficient amount of body fluid in the absence of load, however, too easy to produce a liquid at normal pressure load caused by movement and activity using absorbent articles containing foam.

The resistance to deflection compression, exercise foam absorbents used in the present invention, can be established by determining the amount of deformation generated in the sample saturated foam material exposed to a certain limiting pressure for a set period of time. For the purposes of the present invention, such measurements can be performed on a foam sample of standard size (cylinders, having a thickness of 0.8 cm and a circular cross-sectional area of 6.5 cm2). Such samples saturated with synthetic urine having a surface tension (655) Dyne/cm and then subjected to a limiting pressure of 5.1 kPa for 15 min, at a temperature of 37oC. deflection generated in this test is expressed in PR is to maintain the type of tests to determine the resistance to deflection of compression is described in more detail below under "test Methods".

Absorbent foam used here, have this resistance to the deflection of the compression and limiting pressure of 5.1 kPa creates a deformation of 5% to 95% compression of the foam structure when it has been saturated to its free absorbent capacity of the artificial urine having a surface tension (655) Dean/see Preferably deformation, resulting in such conditions, will vary from 5 to 75%, more preferably from 5 to 50%. For the preferred MDF pen according to the present invention, the resistance to deflection of compression can be adjusted to strain values within the above ranges through the appropriate choice of monomer, co monomer and educational cross-linking, as well as concentrations in combination with the choice of appropriate education emulsion and the conditions and methods of emulsion polymerization. Thus, such preferred foam can be formed from a foam material with a sufficiently large elastic modulus, to provide adequate resistance to the deflection of the compression even if such foams have a low density and have a very thin rack to ensure a high specific surface area.

In) Flexibility.

Absorbent baroudi products corresponding to the shape of the body using. Characteristics of absorbent foams according to the invention as a flexible means, therefore, that these foam can deform or bend to such an extent necessary for use in such absorbent articles without significant damage or violation of their structural integrity, or significant loss of their absorbent properties.

Preferred absorbent foam according to the present invention must be flexible enough to withstand the compressing or deforming the effort force during preparation, processing, packaging, shipment and storage of absorbent articles containing such foam materials. Disposable diapers, for example, are usually Packed and sold in a folded state, in which the cores of the diaper folded in both longitudinal and transverse directions. Disposable diapers are usually sold in packs of folded diaper, with tutu surrounded and pressed by other packages. Therefore, compressing and deforming efforts, the effect of which the foam absorbents are in the process of manufacture and sale, may be significantly greater than those cocoa, which must withstand absorbent foam, the preferred absorbent foam materials according to the present invention will have the characteristics of flexibility, which can be quantified by reference to their ability to withstand bending without significant damage or violation of their structural integrity. Below under "test Methods" describes the method of determining the flexibility of the absorbent foams according to the invention by determining whether the number of times frothy sample of a given size to be bent around a cylindrical mandrel with the set speed without failure. Preferred foams according to the present invention are those that are flexible enough, as a result, in the place of their use as absorbent material for body fluids, rich foam material at 37oC may be subject to such shorter Flex test without failure (i.e., shows the magnitude of bending at least one cycle). More preferably, the preferred foam can be bent at least two times, and even more preferably at least 5 times without fracture when subjected to such testing.

Recovery deflection compression refers to the tendency or predisposition of a piece of foam material to return to its original dimensions after deformation or compression under the action of the effort occurring during manufacture, storage or use. For the purposes of the present invention the recovery of deflection compression preferred foam absorbents here should depend on the pins with the appropriate location and often in these conditions, the foam will contain the absorbed body fluids, therefore, the recovery of deflection of compression can be measured at the pins, which are dry or saturated artificial urine.

The appropriate method of determining Vosstanie and release standard size foam sample, which is either dry or saturated to its free absorbent capacity of artificial urine. Samples are maintained under 50% compression for a set period of time and then released from compression. The amount by which the sample recovers its thickness within one minute after removal of the compressive efforts, is taken as a measure of recovery from bending compression (elastic) sample.

Preferred absorbent foam according to the present invention will usually have a recovery of at least 35% of their original thickness when dry, and/or at least 75% of their original thickness when wet, after one minute. More preferably, such a preferred foam materials will have recovery deflection compression of at least 90% dry and/or 80% wet.

2) the integrity of the foam and soft.

Although it is not necessary for the implementation of existing or used absorbent structures, however, MDF foam absorbents according to the present invention will be preferable to have additional mechanical properties of structural integrity during use and softness (lack radhaiah, as baby diaper, will often be exposed to both dynamic and static effort increment when using walks, runs, crawls or jumps. Such efforts may not only seek to compress the foam absorbents and squeeze out of them the liquid, but also to break or otherwise destroy the foam structure. Apparently, it would be desirable for foam structures used so that they have sufficient structural integrity to minimize possible damage to the foam you are using.

Frothy elements according to the present invention can also be used in absorbent articles, as described in more detail below, in designs, in which the surface of the foaming material is located in close proximity or even contact with the skin using. Therefore, it would be very desirable for the surface of the foam absorbents according to the invention, so that it was quite soft and not irritating the skin in contact with it.

Ill) Characteristics of transportation and namely liquid.

Absorbent foam having an appropriate polymer composition, structural characteristics of the perform transportation and assorbimento or absorption capacity. These characteristics, in turn, are a distinctive feature of the preferred foam materials according to the invention, which make such foams are particularly suitable for use in absorbent structures and absorbent products to take in and hold water body fluid.

Characteristics transportability and namely liquid, which is the most appropriate for the implementation of the respective absorbent foam are:

A) in equilibrium, the absorbent capacity of the foam, especially under the action of pressure,

C) the vertical speed of the absorption liquid through the foam structure,

C) an absorbent capacity of the foam on a specially specified altitudes, and

D) the ability of the absorbent foam structures to divert fluid (divide) from participating absorbent structures with which the foam can be in contact.

Each of these characteristics is described in more detail as follows:

A) an Absorbent capacity and absorbent capacity.

Absorptive capacity is the total number of test fluid (synthetic urine), which is given foam sample is absorbirovannaya respect to the amount of the liquid, held under the absence of limiting pressure (spare capacity), which foam will hold its cellular structure, when the foam sample is subjected to compressive forces. Such measurements absorbent ability, made for the purposes of the invention, calculated in the equilibrium state, i.e. after foam sample was taken and/or keeps all what he can to keep the liquid for any period of time to fully saturate the foam sample of the test fluid. Foam materials are particularly suitable as absorbents in absorbent products such as diapers, will exceed the minimum of the free absorbent capacity and will also exceed the minimum absorbent capacity under pressure.

Using the methodology described in more detail below under "test Methods", free absorbent capacity and absorbent capacity under pressure can be determined for any given foam sample using the method of gravimetric analysis. With this method foamy given sample of known size and weight is placed in the tub with the test liquid (synthetic urine), where he absorbe the account by the amount of liquid held per gram of foam, i.e., the measured free ability. Then this rich foam sample is subjected to stepwise increasing compressive pressure in several increments, while squeezing the liquid is removed at each stage. The amount of fluid held in the sample at each loading pressure to 6.9 kPa was determined gravimetrically.

To be particularly suitable for use in absorbent articles for absorbing urine, frothy absorbents according to the present invention should be free equilibrium capacity (ability) component of at least 12 and preferably at least 20 ml of synthetic urine per gram of dry foam material. In addition, the capacity of such foam materials under the action of the limiting pressure of the order of 5.1 kPa, acting for 15 min, at a temperature of 37oC should be at least 5%, more preferably at least 20% of the equilibrium free capacity of such pins.

C) Characteristic vertical capillary overflow.

Another feature of the transport fluid in absorbent foams, used in the ISM through their foam structures. Vertical capillary wicking or absorption, i.e. the absorption of fluid in the direction opposite to the gravitational effort is particularly desirable property absorbent foam materials according to the invention. This is because such materials will often be used in absorbent articles such that the absorbent liquid must move product from a relatively lower position in a relatively higher position within the absorbent core of the product.

The ability of vertical absorption is associated with the magnitude of the driving force of capillary suction that moves the fluid through the foam and holds it in the foamy structure. Distinctive settings foam regarding its susceptibility to vertical absorption is, therefore, an indication of how well the preferred foam according to the invention will perform its function of absorbent structures in absorbent articles. For foam absorbents according to the present invention the tendency to absorb the liquid can be determined using the test speed vertical absorption and test the capacity of absor speed vertical absorption measured time, necessary for the absorption of the painted test fluid (e.g., synthetic urine) of capacity on the vertical distance of 5 cm through a test strip of foam of predetermined size at a temperature of 37oC. the test speed vertical absorption described in more detail below in the section test Methods. To be particularly suitable for absorbent articles for absorbing urine, frothy absorbents according to the present invention will preferably have a vertical speed of absorption of 5 cm in no more than 30 min when absorb synthetic urine (655) Dean/see More preferably, the preferred foam absorbents according to the present invention will have a vertical speed of absorption of 5 cm in no more than 5 min, with the absorption of synthetic urine.

2) the Absorbent capacity of the vertical absorption.

Tests absorbent capacity vertical absorption are performed in conjunction with testing speed vertical absorption. The absorbent capacity of the vertical absorption measures the amount of test fluid per gram of absorbent foam that soaks into every inch (2.54 cm) vertically in the aqueous absorption. This definition is usually carried out after the sample vertically absorbed the test liquid to the equilibrium state, for example after 18 hours. As the test speed vertical absorption test absorbent capacity vertical absorption described in more detail below under "test Methods".

To be particularly suitable for absorbent articles for absorbing urine, the preferred foam absorbents according to the present invention will typically have an absorbent capacity of the vertical absorption that when the height of the vertical absorption 11,4 cm foam test strip has an absorbent capacity of at least about 10 ml of artificial urine ((655) Dyne/cm per gram of absorbent foam. More preferably, the preferred foam absorbents according to the invention will have an absorbent capacity of the vertical absorption when 11,4 cm from 20 to 45 ml of synthetic urine per gram of foam.

C) Distribution.

The absorbent foam structures according to the invention will often be used in absorbent products together with other types of absorbent structures that tatie structure according to the invention are primarily used as a storing/distributing the liquid component in absorbent products, for these pins, it is desirable to have a predisposition to the direction of body fluids in the foamy structure of other absorbent components, which also absorb such fluids. This tendency to exhaust fluid from the other components of the absorbent articles are known in the art as "distribution". The idea of distribution and some methods of determining the characteristics of the distribution are described, for example, Weisman/Goldman; U.S. patent N 4610678, issued September 9, 1936, When tested by the characteristic distribution using techniques similar to those described in U.S. patent N 4610673, absorbent foam structures according to the present invention exhibit especially desirable characteristics of the liquid distribution.

IV) Preferred MDF absorbent foam.

As noted earlier, a particularly preferred absorbent foam materials which can be prepared to have the required and preferred structural, mechanical and transporting fluid characteristics, as described above, are products derived from the polymerization of certain emulsions of water in oil, having according to the invention otnositel the relationship of water to oil, known in this area as emulsions with high dispersed phase (MDF or emulsion "MDF"). Preferred polymeric foam materials derived from the polymerization of such emulsions are referred to here as "MDF-pins".

The appropriate amount of water and oil phases used to form the polymer foam substances predecessor MDF emulsions, are among many other parameters important in determining the structural, mechanical and performance properties of the resulting preferred polymeric foams. In particular, the ratio of water to oil foaming emulsion can affect the foam density, cell size, specific surface area of the foam and the size of the uprights forming the foam. The emulsion used to prepare the preferred polymer MDF foam materials according to the present invention will usually have a ratio of aqueous phase to oil phase is of the order of from 12: 1 to 100:1, preferably from 20:1 to 70:1, and more preferably from 25:1 to 50:1.

Continuous oil phase of the emulsions used to prepare the preferred MDF pen here contains monomers which undergo polymerization for the formation of Tennent forming a cross-link agent. Selection of particular types and amounts of monofunctional main monomers(a) and co monomer(s) and polyfunctional forming a cross-link agent(s) may be important for the implementation of the absorbent MDF foam materials having the desired combination of structural, mechanical and transporting the fluid properties that make such materials receipts for use in the present invention.

The main monofunctional monomer component used in the oil phase of the preferred foamy substance predecessor MDF emulsion contains one or more monomers, striving to give a glassy type properties of the ultimately obtained foamy structure. Such monomers will be called hereinafter "vitreous" monomers and for the purposes of this invention, defined as Monomeric materials which will form the homopolymers with high molecular weight (more than 6000) having a glass transition temperature Tg above about 40oC. the Preferred type of glassy monomer is a monomer on the basis of styrene, which itself is the most preferred monomer of this type. Can be used substituted, for example, monosaturated order from 3 to 41%, more preferably, about 7 to 40% by weight of oil phase used to form MDF emulsion, which is supposed to cure.

Monofunctional comonomers component, which will also be present in the oil phase MDF emulsion together with the vitreous main Monomeric material contains one or more comonomers, striving to give a rubber-type properties of the obtained ultimately foamy structure. Such comonomers in the future will be called "kucukodabasi" comonomers and for the purposes of this invention, defined as Monomeric materials which will form the homopolymers with high molecular weight (more than 10000) having a glass transition temperature Tg40oC or below. Monofunctional kucukodabasi comonomers of this type include, for example, alkylacrylate, alkyl methacrylates, allylacetate, butadiene, substituted BUTADIENES, halide vinylidene and combinations of such comonomers and comonomer types. Preferred kucukodabasi comonomers include butyl acrylate, 2-ethyl hexyl acrylate, butadiene, isoprene and combinations of these comonomers. From all these samples, the most preferred are butylamide from 27 to 73%, more preferably from 27 to 66% by weight of oil phase.

In MDF the emulsion used for forming the preferred absorbent foams according to the invention both monofunctional glassy main monomer(s) and monofunctional kouchkovsky comonomer(s) must be present in the oil phase in the above concentration ranges. In addition, the molar ratio of monofunctional glassy monomer component to a monofunctional koucouloutou component will typically be of the order of from 1:25 to 1.5:1, more preferably from 1:9 to 1.5:1.

Since the polymer chains formed from glassy monomer(s) and kauchukopodobnoe of co monomer(s) shall be cross linked, then the oil phase of the emulsions used for education preferred MDF-pins according to the invention should also contain a polyfunctional forming a cross-link agent. As with monofunctional monomers and comonomers, the choice of a specific type and quantity of forming a cross-link agent is very important for the final implementation of the preferred polymeric foams having the desired combination of structural, mechanical and asmonaean and comonomers, and on the desired characteristics of the implemented ultimately preferred polymeric foams, polyfunctional forming a cross-link agent for use in the substance predecessor preferred MDF emulsion may be selected from a wide range of multifunctional, preferably bifunctional monomers. Thus, forming a cross-link agent can be divinecaroline.com material, as, for example, divinylbenzene, dividercolor or diallylphthalate. Or divinyl aliphatic education cross-linking, as, for example, any of diacrylate acid esters of polyhydric alcohols that can be used. Forming a cross-link agent, turned out to be most suitable for making the most acceptable foam of the preferred MDF emulsions is divinylbenzene.

Forming a cross-link agent of any type will normally be used in the oil phase of the preferred foaming emulsions according to the invention in quantities of from 3 to 40%, more preferably about 10 to 25% by weight. The number of forming a cross-link agent(s) within such ranges will usually form motherwise on the total amount of monomers, present in the oil phase. The main part of the oil phase is preferred MDF emulsions according to the invention contains the above-mentioned monomers, comonomers and forming a cross-link agents, which ultimately form the preferred polymeric foam absorbents. Therefore, it is important that these monomers, comonomers and forming a cross-link agents were mostly insoluble in water, resulting in they are mostly soluble in the oil phase and not in the aqueous phase. The use of such essentially water-insoluble Monomeric materials ensures that the preferred MDF emulsion with the appropriate characteristics and resistance will be realized.

It is desirable, of course, to the monomers, comonomers and forming a cross-link agents used to retrieve the preferred polymeric foam materials according to the invention, would be of the type that derived ultimately foamy polymer was non-toxic and therefore chemically stable. Thus, such monomers, comonomers and forming a cross-link agents must have a minor or may not have quite the toxicity is very low residual is.

Another important component of the oil phase MDF emulsions used for the preparation of polymeric foams according to the present invention contains an emulsifier capable of forming a stable MDF emulsions. Such emulsifying agents are soluble in the oil phase used to form emulsions. Used emulsifiers can be nonionic, cationic, anionic or amphoteric, provided that the emulsifier or combination of emulsifiers to form a stable emulsion. Preferred types of emulsifiers that can be used for education emulsifier component having the appropriate characteristics include ether of sorbitol and fatty acids, ether polyglycerol and fatty acids, polyoxyethylene (PoE) fatty acids and esters, especially preferred are esters of sorbitol and fatty acids, for example, sorbitol of monolaurate (SPANQ20), sorbitol of monolaurate (SPANQ80) and a combination of sorbitol of trioleate (SPANQ85) and sorbitan monooleate (SPANQ80). One such particularly preferred combination of the emulsifier contains a combination of sorbitol of monooleate and sorbitol of trioleate in a weight ratio of greater than or equal to poradek the ski available ether-polyglycerols, sold by Grinstead, and ABSORB 2502, which sorbitol of sesquioleate sold by the company Henkel.

Emulsifier component is usually of the order of from 2 to 33% by weight of oil phase used for the formation of MDF emulsions, which in turn are used to prepare the preferred polymeric foams according to the invention. More preferably, the emulsifier component will be of the order of from 4 to 25% to the weight of the oil phase.

In addition to the monomer and emulsifier components described above, the oil phase used to form the polymerized MDF emulsions may also contain additional optional components. One such optional component of the oil phase may be soluble in oil, the polymerization initiator conventional type, which will be described below. Other possible optional component of the oil phase can be substantially water-insoluble solvent for the monomer and emulsifier components of the oil phase. The solvent of this type of course should not dissolve the resulting ultimately polymerized monomers. The use of such solvent is not preferred is Jana phase.

As described earlier, MDF oil phase is the continuous phase in the emulsion polymerized to implement the preferred foams according to the present invention. A discontinuous dispersed phase polymerized MDF emulsion is an aqueous phase, which is usually an aqueous solution containing one or more dissolved components. One significant dissolved component of the aqueous phase is water-soluble electrolyte. Dissolved electrolyte in the aqueous phase MDF emulsion serves to minimize the tendency of the monomers and of the originators of cross-linking soluble primarily in oil, to dissolve in the aqueous phase. This, in turn, can minimize the extent to which during the polymerization of the emulsion polymer material fills the open pores or cells of the interface oil/water formed by the bubbles of the aqueous phase. Thus, the presence of electrolysis and the resulting ionic strength of the aqueous phase can determine whether and to what extent will the resulting preferred polymeric foam having open pores.

You can use any electrolyte that allows ion to give the ionic strength of the aqueous phase is, Astoriya in water halide, such as, chlorides, nitrates and sulfates of alkali metals and alkaline earth metals. Examples include sodium chlorite, calcium chloride, sodium sulfate and magnesium sulfate. Calcium chloride is the most preferred for use in these preferred versions of the present invention.

Typically, the electrolyte to be used in water foyer MDF emulsions, which are substances predecessors preferred polymeric foams according to the invention in concentrations that change the order of from 0.2 to 40.0% by weight of the aqueous phase. More preferably, the electrolyte will be of the order of from 0.5 to 20.0% by weight of the aqueous phase.

MDF emulsion used to prepare the preferred polymeric foams, will usually contain a polymerization initiator. Such initiating component is typically added to the aqueous phase MDF emulsions and can be any conventional water-soluble initiator of free radical polymerization. Materials of this type include peroxide compounds, such as, for example, persulfates, sodium, potassium and ammonium peroxide of caprylyl, benzoyl peroxide, hydrogen peroxide, Gidropress hydroperoxide, tertiary boutillier Ichnya redox initiation system. Such systems are formed by combining the above-mentioned peroxide compounds with a reducing agent, for example, sodium bisulfite, L-ascorbic acid and salts containing divalent iron.

Initiating material may be of the order of up to 5 mol.%, based on the total number of moles of polymerized monomers present in the oil phase. More preferably, the initiator is of the order of from 0.001 to 0.5 mol. % based on the total moles of the polymerized monomers in the oil phase. When used in the aqueous phase of such initiator concentration can be realized by adding the initiator to the aqueous phase in amounts of about 0.02 to 0.4%, more preferably about from 0.1 to 0.2% by weight of the aqueous phase.

Using the process described in more detail below, the oil and water phase as described above, are combined under stirring to obtain an emulsion in the form of a stable foam. This AWDF the foam is then exposed to polymerization conditions which are sufficient and appropriate to implement the polymerization of the monomers in the oil phase, and thereby forms a rigid cellular foam structure.

Chemical nature, composition and pestilence and concentration of monomers, the comonomers and the originators of cross-linking used in MDF emulsion and primenyaemye conditions of emulsion polymerization. Such polymeric material is usually kinabuhayan in aqueous solution in the sense that the material does not significantly plastification or absorbs aqueous liquids in contact with them. However, regardless of the specific monomer composition, molecular weight or morphology of the polymer material, the resulting preferred polymeric material is typically viscoelastic in nature. Thus, the polymer preferably foam structure according to the invention will have a viscosity, i.e. the properties of the liquids and elastic properties, i.e. the properties of the springs. It is very important that the polymeric material forming the porous foam structure, has a physical, rheological and morphological qualities in terms of use were given appropriate flexibility, resistance to the deflection of the compression and dimensional stability of absorbent foam material.

Mesh polymer material forming the preferred absorbent foam structures according to the invention is preferably free from polar functionaries, forming the surface of the foam structures of such preferred absorbent foams, is usually relatively hydrophobic in nature. Therefore, preferred that the cured foam may require additional treatment to make the surface of the foam structures are relatively more hydrophilic so that these foams could be used as absorbents for aqueous body fluids. Hydrophilicity surfaces of the foam, if necessary, can usually be carried out by processing structures MDF pins, as they polymerization gidrofiliziruyuschim agent method, described in more detail below.

Hydrotribromide agents can be any material that enhances the wettability of polymer surfaces with which they come in contact and on which they are deposited. Hydrophilidae agents are well known in the art. Such known agents typically include surface-active materials, anionic, cationic or non-ionic type. Usually Hydrophilidae agents are used in liquid form, dissolved in water for water education hydrophilizing solution, applied to the surfaces MDF foam. So about the WDF pins in quantities enough to make them essentially hydrophilic, but without changing the desirable characteristics of flexibility and deflection of the compression of the foam. In the preferred foams processed hydrotribromide agents, hydrophilicity agent is included in the foam structure so that the residual amount of agent remaining in the foam structure are of the order of from 0.1 to 10.0% by weight of the foam.

One type of suitable hydrophilizing agent contains a soft non-irritating to the skin surface-active substances applied to the foam structure in quantities sufficient to provide residual surfactants in the foam in amounts of the order of from 0.5 to 5.0% by weight, more preferably about 1 to 3% by weight based on the weight of the foam. Such surfactants can include, for example, alkyl sulphates and alkylalkoxysilane sulfates such as those that are used in commercially available posudomoya liquids such as liquid detergent joy. Aqueous solutions of these surfactants are usually used for washing MDF foamy structures or after removal of residual materials of the aqueous phase remaining after the operation of polymerization of the foam, or that more psi.

Another preferred type hydrophilizing agent contains hydratious and preferably hygroscopic or deliquescent, soluble in water inorganic layers. Such materials include, for example, Toxicological acceptable salts of alkaline earth metals, materials of this type and their use in combination with water-insoluble surfactants as hydrophilicity of foam agents, described in more detail in patent application U.S. Thomas A. Desmarais, ser. N 743951*, (P & G case N 4454), filed simultaneously with this application in the USA and is provided here for information. Preferred salts of this type include halide calcium and magnesium, for example calcium chloride, which, as discussed below, can also be used as the electrolyte in the aqueous phase MDF emulsions used to prepare the preferred absorbent foams.

Hydrophilidae agents in the form of hydrated inorganic salts can easily be included in the absorbent foam by treatment with aqueous solutions of these salts. As in the case of surface-active hydrotribromide agents, hydrating solutions of inorganic salts can usually is the removing of the residual aqueous phase from the polymerized foam. The contact pins such solutions are preferably used for the deposition of hydrated inorganic salts such as calcium chloride, residual quantities, constituting about 0.1 to 7% by weight of the foam.

Hydrophilicity processing those preferred foam structures, which are relatively hydrophobic, when polymerized, will usually be carried out to such an extent that is necessary and sufficient to give the corresponding hydrophilicity preferred MDF foams of the present invention. However, some preferred foam MDF emulsions can be sufficiently hydrophilic after cooking and, therefore, do not require additional processing hydrotribromide agents. In particular, such preferred MDF the pins may be those in which the ester of sorbitol and fatty acids are used as emulsifiers added to the oil phase, and calcium chloride is used as the electrolyte in the aqueous phase predecessors foam MDF emulsion. In this case, the residual liquid water phase is held in the pen after polymerization, may or may precipitate a sufficient amount of calcium chloride to make containing ostatni emulsion foam.

V) Methods of making absorbent foam.

Absorbent foam materials according to the present invention can be prepared using any appropriate stages of the polymerization and after polymerization processing, and using any suitable combination of Monomeric materials until you have received hydrophilic foam having the above-described essential and, if required, the preferred structural and mechanical characteristics. As noted, the preferred method of implementation of polymeric foams having the required structural and mechanical characteristics, as well as having the desired properties for the transportation of liquids, include a polymerization emulsions with high variance phase MDF. Let us now consider the preparation of absorbent foams using this preferred method, to show how you can get foam type considered here.

This preferred method of preparation of foam include the following:

A) formation of a stable emulsion with high dispersed phase (MDF) ;

B) polymerization then this stable emulsion under conditions suitable for the formation of the solid polymer froth the e treatment with water and/or liquid hydrotribromide agents to remove the original residual water phase from the polymer foam structures and deposition of any required hydrophilizing agent; and

D) then dewatering this polymeric foam structure to the extent necessary to make foam material suitable as absorbent of aqueous body fluids.

Each of these basic operations process is described in more detail as follows:

A) Education MDF emulsion.

Substance predecessor MDF emulsion for the preferred absorbent foam materials according to the invention, can be formed by combining the oil phase, as described above, with the aqueous phase, as described above. The weight ratio of water phase to oil phase, and the combination will usually be of the order of from 12:1 to 100:1, more preferably from 20:1 to 70:1. The oil phase used for the formation of MDF emulsions here will contain the above essential components, for example, the desired monomers, comonomers, the originators of cross-linking and emulsifiers. The oil phase may also contain optional components, such as solvents and polymerization initiators. The aqueous phase used to form MDF emulsions according to the invention, will contain the electrolyte, as necessary components is atory polymerizatio .

MDF emulsion may be obtained from combined oil and water phases by shear mixing this combination of phases.

Shear mixing is usually carried out to such an extent and within the time required to obtain a stable emulsion of the combined oil and water phases. Such a process can run or on a batch or on a continuous basis and is usually carried out under conditions appropriate to obtain emulsion in which droplets of an oil phase dispersed to such an extent that the cured foam formed in the end of the emulsion will be required volumes of pores and other structural characteristics. The emulsification combination of oil and water phases will often include the use of mixing or mixing device, for example, a finger agitator.

One preferred method of forming MDF emulsions, which can be used according to the invention, provides for a continuous process of combining and emulsifying the required oil and water phases. In such a process produces a jet of liquid containing an oil phase, as described above, which has a flow rate of from 0.08 to 1.5 ml/s. adca from 4 to 50 ml/s. When flow velocities in the above ranges of these two streams are then combined in an appropriate mixing chamber or zone so that the desired weight ratio of water in the oil, above, near, as the process is achieved and maintained. In the mixing chamber or zone combined flows are usually subjected to shear mixing, which, for example, is provided with a finger agitator appropriate shapes and sizes. The shift is usually to put a value on the order of from 1000 to 4000 c. The residence time in the mixing chamber will range from 5 to 30 seconds After receiving MDF emulsion in liquid form is removed from the mixing chamber or zone with a flow rate of about 4 to 52 ml/s

This is the preferred method of formation used MDF emulsions by means of a continuous process is described in more detail in the patent application U.S. Thomas A. Desmarais, Stephen T. K. dick and Thomas M. Siwale, ser. N 743.947*(P & G case N 4453). This application filed simultaneously with this in the US, please see here for details.

B) Polymerization MDF emulsion.

MDF emulsion obtained as described above, is usually placed in Ipodnano polyethylene, from which polymerized ultimately solid foam material can be easily removed for further processing after completion of the polymerization at the desired degree.

The conditions of polymerization, which is exposed MDF emulsion will vary depending on the monomer and another part of the oil and water phases of the emulsion, and the type and quantities used of the initiators of polymerization. However, often the conditions of polymerization will include maintaining MDF emulsion at elevated temperatures of the order of from 55 to 90oC, more preferably from 60 to 66oC during the time of the order of from 4 to 24 hours, more preferably about 4 to 12 hours.

C) Washing and gidrogenizirovanii MDF foam.

Solid MDF foam formed at the end of the above-described phase polymerization is essentially flexible, open porous structure, the cells of which are filled with the remaining material from the aqueous phase used for the preparation of MDF emulsion before polymerization. This residual material of the aqueous phase, containing mainly an aqueous electrolyte solution, the residual emulsifier and a polymerization initiator, must be removed from the foam structures n the phase will typically be carried out by compressing foam structures for extrusion of residual liquid and/or rinsing foam structures with water or other aqueous washing solutions. It often takes several compression and washing, for example, two cycles. After reducing the content of the source material of the aqueous phase in the foam structure to the desired value MDF foam may require processing, i.e., continuous washing with an aqueous solution of the corresponding hydrophilizing agent. Hydrophilidae agents that can be used are listed above. As noted, the processing MDF foam structures with a solution hydrophilizing agent continues, if necessary, up until the required number hydrophilizing agent will not be included and while the foam will not show the desired amount of adhesion voltage to any selected test fluid.

D) Dehydration foam.

After processing MDF foam to the state is required to make the ultimately dried foam, respectively hydrophilic foam will usually be dehydrated before cutting or other preparation for use as an absorbent structure in an absorbent product. The dehydration may be carried out by compressing the foam to press out residual water, by affecting the foam or contained elevated water temperatures, aprisiate and water heating. Phase dehydration processing MDF foam will usually be made up until the last, ready to use, there will be almost dry. Often these dehydrated by compression of the foam will have a water content /moisture of the order of from 50 to 500%, more preferably from 50 to 200% by weight based on dry weight. Subsequently, the heated foam is dried to a moisture content of from 5 to 40%, more preferably from 5 to 15% based on dry weight.

VI) Absorbent articles,

The present invention also concerns an absorbent body fluid products using foam absorbent structure, at least as part of their item absorbent liquid "core". By "absorbent article" refers to the consumer product, which is able to absorb significant quantities of urine and other fluids like liquid peculiar (disorder of the intestines), catching the user suffering from incontinence, or user product. Examples of such absorbent articles can serve as disposable diapers, underwear for those suffering from incontinence, disposable training pants, strong gaskets, etc. Absorbent foam structure is underwear for them, protection for clothes, etc. In its simplest embodiment, the absorbent product according to the present invention must contain only relatively impermeable to fluid back sheet and one or more foam absorbent structures that interact with the back sheet. Foam absorbent and the back sheet will interact in such a way that the material of the foam absorbent structure is located between the rear sheet and place of receipt of fluid from using absorbent product. Impervious to liquids rear sheets may contain any material, such as polyethylene or polypropylene, having a thickness of about 0.038 mm, which will contribute to the retention of fluids in the absorbent product.

Typically, absorbent articles here will also include permeable to fluid top sheet covering the side of the absorbent product, which comes in contact with skin use. In this design the product contains an absorbent core having one or more foam absorbent structures according to the present invention, located between the rear and upper leaves. Permeable to liquid, the upper sheet may contain any material, as for example, the spine of the body through it and into the underlying absorbent core. The material of the upper sheet preferably will not have properties in the retention of body fluids in the area of contact between the top sheet and skin benefiting.

The absorbent core embodiments of absorbent articles according to the present invention may be entirely composed of one or more foam structures here. For example, the absorbent core may contain one United piece of foam with the desired or required shape to fit the type of absorbent product in which it should be used. Alternatively, the absorbent core may contain a large number of foam pieces or particles, bonded together with glue or combined together in a non-fastened the block and held in place by wrapping a shell cloth or using the top and back sheets of absorbent products. The absorbent core of the absorbent articles according to the invention may also contain other common elements or materials in addition to one or more foam absorbent structures according to the present invention. For example, absorbent articles according to the invention may use an absorbent core that m structures and conventional absorbent materials, such as:

a) wood pulp or other cellulosic fibers and/or b) particles or fibers of polymeric gelling agents.

In one embodiment, the invention includes a combination of foam absorbent material according to the invention and other absorbent materials and absorbent articles can use a multi-layer design of absorbent core in which the core layer containing one or more foamy structures according to the present invention may be used in combination with one or more additional layers of the core, containing conventional absorbent structures or materials. Such conventional absorbent structures or materials, for example, may include air laid or wet cloth wood cellulose or other fibers. Such conventional structure may also contain common, for example, with large cells absorbent foam or even sponges. Conventional absorbent structures used with a foaming material according to the invention can also contain, for example, up to 80% by weight of the particles or fibers of polymeric gelling agent, commonly used in absorbent izdelka type and their use in absorbent products are more fully described in the Brandt/Goldman/Inglin, U.S. patent N R e 32649 issued after re-examination, re-issued April 19, 1988, is given here for information.

One preferred type of absorbent articles according to the invention uses a multi-layer absorbent core having an upper receiving/distributing the liquid layer containing the layer of modified cellulose fibers, for example, reinforced twisted cellulosic fibers and optionally up to 10% by weight of this receiving/distributing liquid layer of polymeric gelling agent. Such multi-layer absorbent core also contains a second, i.e., the lower store/redistributing the liquid layer having a foam structure according to the present invention. (For the purposes of the present invention, the "top" layer of the multilayer absorbent core layer is located closer to the user's body, for example, the layer closest to the top sheet of the product. The term "lower" layer opposite means a layer of a multilayer absorbent core, which is relatively removed from the body using, for example, the layer closest to the rear sheet products). Modified cellulose fibers used in the receiving/distributing the pulp, which were hardened and twisted by means of chemical and/or thermal treatment. Such modified cellulose fibers are fibers of the same type as those used in absorbent articles described dash and Thompson; U.S. patent N 4935622, issued June 19, 1990, are listed here for information. Absorbent product using absorbent foam structures, according to the present invention, in storing/redistributing the liquid layer below the receiving/distributing liquid layer containing a hardened tortuous cellulose fibers, are described in more detail in the patent application U.S. Gerald A. Yong, D. gray of lavona, Regory C. Taylor, having N 743950*(P & G case N 4452), simultaneously filed in the United States with this application. This application is shown here for information.

As noted earlier, the characteristics of the transport fluid and mechanical characteristics of special foam absorbent structures according to the invention make them particularly suitable for use in absorbent products such as disposable diapers. Disposable diapers containing absorbent foam structure according to the present invention can be manufactured with ispolz ("air felt") or absorbents modified cellulose core, used in conventional diapers, the one or more structures of the present invention. Foam structures according to the present invention can thus be used in diapers in the form of a single layer or, as noted above, in various configurations of the multilayer core. Products in the form of a disposable diaper is described in more detail in Duncan and Baker, U.S. patent, replaced by N 26151, issued January 31, 1967; Duncan, U.S. patent N 3592194, issued July 13, 1971 ; Duncan and Gellert, U.S. patent N 3489148, issued January 13, 1970; Buell, U.S. patent N 3860003, issued January 14, 1975; and Alemany and Berg, U.S. patent N 4834735, issued may 30, 1989, all of which are listed here for information.

Preferred disposable diaper according to the present invention shown in Fig. 2. This diaper includes an absorbent core 50 having an upper receiving liquid 51, and the underlying storing/distributing liquid layer 52 containing foam absorbent structure according to the present invention. The top sheet 53 is overlying and of the same length with one surface of the core, and impervious to liquid back sheet 64 is overlying and one length with the surface serdechnyiy, than that of the core, thereby forming the side edge part of the rear sheet supporting core. The diaper preferably has the shape of an hourglass.

Another preferred type of absorbent products that can use foam absorbent structures according to the present invention contains a form-retaining product, such as training pants. Such a form-retaining products typically contain a non-woven flexible substrate chassis, which given the shape of short underpants or shorts. Foam absorbent structure according to the present invention, may then be attached to the perineal part of such chassis to serve as absorbent "core". Such absorbent core may often feel cozy during shell fabric or other permeable for liquids non-woven material. Such wrapping of the core serves, therefore, as a "top sheet" for a form-retaining absorbent products.

The flexible substrate, forming a chassis that keeps the shape of the product may contain a fabric or paper or other types of non-woven strip or molded diaper, and can also elasticites or to take any other mod is Ksenia fit products. These substrates are typically made relatively impervious to liquid or at least not easily permeable to liquid by treating or coating one surface or layering this flexible substrate other relatively impervious to the liquid layer, thereby making all of the chassis is relatively impermeable to fluid. In this case, the chassis serves as a "back sheet" for preserving the shape of the product. Typical training pants of this type is described in Roberts, U.S. patent N 4619649, issued October 28, 1936, is shown here for information.

Typical a form-retaining product in the form of training pants shown in Fig. 3. This product contains the outer layer 60 attached to the cladding layer 61 by means of glue along its peripheral areas. For example, the inner casing 61 can be attached to the outer layer 60 along the periphery of one portion of the leg cuff 62; along the periphery of the other 63 foot cuffs; along the periphery of the area 64 of the waist. To the perineal part of the product attached rectangular absorbent core 65 containing foam absorbent structure according to the present invention.

Testing methods.

mechali, these characteristics can be determined using the following test liquids and test methods.

I) the Test fluid and the preparation of the foam sample.

A) the Test fluid is synthetic urine.

The number of measurements described here when testing include the use of the test fluid, for example, synthetic urine, ethanol or isopropanol. Artificial urine used in several tests, described below, is prepared from commercially available preparation of the artificial urine, manufactured Pharmaceuticals (Mechanicsburg, PA, 17055). Such artificial urine, Geico made from the drug, contains (wt.%) KCl 0,2; Na2SO40,2; NH4H2PO40,085; (NH4)2HPO44 0,015; CaCl22H2O 0,025; MgCl26N2O 0,05. Samples of artificial urine are prepared in accordance with the directions on the label using distilled water. To facilitate the dissolution of a salt mixture of Geico slowly added to the water. The sample is filtered, if necessary, to remove any particles. Any unused urine is removed after a week. To improve visibility of the liquid five drops of blue food CRA tension (655) Dean/see

C) preparation of a foam sample.

The following tests includes the preparation and testing of foam samples of concrete with a specified size. If no special instructions, the foam samples of the required size should be cut from larger blocks of foam using a sharp reciprocating saw blade. The use of such or similar cutting foam is used mainly in order mainly to repair damage to the edges that otherwise would have a negative impact on some measurements when performing the following series of operations tests. The characteristic size of the sample will also include its thickness.

Thickness measurements for the purposes of the present invention should be carried out when the foam sample is under the limiting pressure of 350 PA.

II) Determination of structural characteristics.

A) Available pore volume.

The procedure for determining the available pore volume includes measuring the amount of isopropanol, flashpoint 12oC, which can be introduced into the structure of the absorbent foam sample. The equipment is also produced at this temperature. Dry foam samples are cut into cylinders of 6.5 0.8 cm thickness or equivalent. Such cylindrical samples can be made using sharp punches diameter 2,87 cm sheets of 0.8 cm of foam. Each dry foam sample is weighed to determine dry weight (SW). Three such sample shall be weighed to determine the average dry weight (SW).

The measured free volume or capacity (SSE) of these samples is then determined using the following operations .

1) the foam Samples are immersed in isopropanol in a Cup-the mould and left to saturate. At this point, the sample may be compressed several times to remove air.

2) Each sample is removed without squeezing him isopropanol. Excess fluid flows from the sample that are in the flat position for 30 sec. Then each sample is weighed in the wet state to determine wet weight (BB).

3) Operations under item 1 and 2 are repeated two more times to calculate the average wet weight (BB).

The measured free volume (SSE, g/g) is the weight of isopropanol in rich foam per unit mass of dry foam. SSE is calculated according to the following form is isopropanol, component 0,785 g/ml This gives cash pore volume for foam in ml/year

C) Specific surface capillary suction.

The specific surface capillary suction foam absorbents according to the invention can be determined from the absorption equilibrium weight of the test liquids with known low surface tension. In this case, using absolute ethanol (flash 10oC). For testing calibrated strip of foam sample of appropriate size (25 cm length x 2 cm width x 0.8 cm thickness) is balanced if (222)oC is vertical and one of its end immersed for 1-2 mm into the tank with ethanol, using for this purpose the laboratory of the lifting table. Ethanol absorbs up foam strip to its equilibrium height, which should be less than the length of the sample. Then containing ethanol strip is weighed, but at the same time continuing to communicate with the capacity to determine the weight of the total quantity of absorbed ethanol. During this procedure, the sample must be closed, for example, a glass cylinder with a lid to prevent evaporation of ethanol.

Specific surface of the foam sample mevania, cm2/g;

Me- the mass of the absorbed liquid ethanol-HE, g;

G is the gravitational constant, equal to 980 cm/s2;

Lntotal length of specimen, cm;

Mn- weight of dry sample, g;

- surface tension of the ethanol-HE, which is 22.3 Dean/see

These values can then be divided by 10000 cm2/m2to obtain specific surface capillary suction, m2/,

C) the density of the foam.

One of the procedures that can be used to determine the density of the foam is that described in Method ASTM N D 3574-86, Test A, which is intended mainly for testing urethane foam, but which can also be used for measuring the density of the preferred MDF type of absorbent foams according to the present invention. In particular, the density measurement performed in accordance with method ASTM produced on foam samples that were pre-prepared in a certain way, as specified in this test. The density is determined by measuring both the dry mass of a given foam sample and its volume at (222)oC. the Volume definitions on large foamy samples races is isih foam samples can be measured using a dial indicator, do not use pressure on the base of the dial 350 PA.

Density is calculated as mass per unit volume. For the purposes of this invention, the density is usually expressed in g/cm3.

III) Determination of mechanical properties.

A) resistance to the deflection of the compression.

The resistance to deflection of the compression ratio can be estimated for the purposes of the present invention by measuring the deformation rate (in % reduction in thickness) formed in the foam sample, saturated artificial urine after application thereto of a voltage in the form of limiting the pressure of 5.1 kPa.

Tests for obtaining such measurements can be carried out on foam samples cylinders prepared, as required above for testing, the available pore volume. Such samples test synthetic urine and the equipment used for these measurements, all of them balanced at a constant room temperature, heated to 37oC. Measurement was also carried out in this room.

Foam samples were placed in a Cup-mould and fill up their free absorbent capacity or ability of the artificial urine, Geico. Then when the, rigidly to determine the thickness, is placed onto the sample. You can use any indicator, fitted leg with a surface area of at least 6.5 cm and is capable of measuring the thickness of the order to 0.025 mm. Examples of such indicators are AMEC, model 482 (Ames Co., Waltham, MA) or It's Sokki model EG 225 (It's Sokki To. Co., Ltd., Japan). Used cargo, used with a dial indicator to create a pressure foot on a foam sample of the order of 6.9 kPa. Rich foam sample on the grid is subjected to a limiting pressure of 5.1 kPa for 15 minutes At the end of this period the dial indicator is used to measure changes in the thickness of the sample, the incident in the application of the limiting pressure. Using the initial and final thickness measurement can be calculated percentage strain for a sample.

In) Flexibility.

The flexibility of the foam can be estimated using the test procedure, which is a modified version of ASTM D 3574-86 tests 3.3, is used to determine the flexibility of limiting cellular polymer foam products. Such a modified test uses foam sample oC. it is Important that the cutting process used to obtain these samples did not lead to defects in the edges of the foam strip. Intense artificial urine frothy band is wrapped around a cylindrical mandrel with a diameter of 0.8 cm with a uniform rate of one coverage for five seconds until the ends of the strip will not meet. The foam is flexible, if it is not torn or destroyed in the course of this test, i.e., if it goes through one cycle of bending.

C) Recovery of deflection compression.

To test the recovery of deflection of the compression specimens, similar to those that were prepared for testing, the available pore volume described above. Such samples represent a cylinder with a thickness of 0.8 cm, having a round cross-sectional area of 6.45 cm2. These foam samples may be tested or in the dry state, or after saturation to their free absorbent capacity of the artificial urine, Geico.

Using a dial indicator test sample or dry or wet compresses for 10 to 50% of its original thickness and is held in a compressed condition within 1 min. After that, the pressure is removed and the foam is given POS is the height of the uncompressed foam.

For testing of dry samples are used, the ambient temperature (222)oC. For testing of wet samples, the latter is saturated up to their free absorbent capacity at 37oC artificial urine, Jaico in a Cup with a diameter of 5 cm Cup serves as a container for the content of the extruding liquid during compression, and performs the role of capacity from which the sample may re-absorb liquid during recovery after compression.

IV) characterization of the transport fluid.

A) an Absorbent ability.

As a free absorbent capacity or ability, and the absorbent capacity under pressure can be determined using gravimetric analytical method using artificial urine as a liquid, which should be calculated absorbent capacity of the foam.

1) test Principle absorbent ability.

In this test, the foam sample is saturated felt artificial urine for measurement beznagruzochnyh or free absorbent capacity of the foam sample. Then applied pressure at different sites to determine the absorbent was sposobstvala in a compressed condition within a certain time.

2) the test Limits.

This test measures the absorbent capacity of the foam sample under pressure, in particular, to 6.9 kPa, and at the temperature of interest, i.e., 37oC.

3) Equipment.

The sieve with the mesh 25, diameter 8 cm, Cup-mold 15 cm diameter x 7.5 cm height; chemical beaker 50 ml, analytical Balon; dial indicator, provided with a foot at least 6.5 cm and is capable of measuring 0,025 see, for example, AMEC model 482 (Ames Co., Waltham, MA) or It's Sokki model EG - 225 (Onno-Sokki To. Co., Ltd., Japan); goods for a dial indicator, capable of creating a pressure of 1.4, 5.1 to 6.9 kPa.

4) Materials.

Artificial urine, Geico; foam sample.

5) Procedure.

I) the Equipment and materials described according to the invention, are balanced at a constant room temperature, heated to 37oC. Measurements were also carried out in this room.

II) Foam samples, similar to those prepared in the trials, the available pore volume, cut into cylinders 6.5 cm20.8 cm thickness. These samples were weighed to obtain the average dry weight (SW).

III) Free abs is immersed in artificial urine in the Cup-the mould and left to saturate. The sample may be compressed several times to remove air.

b) the Foam is removed without extrusion of the liquid. Excess fluid flows from the sample that are in the flat position for 30 seconds, and then the wet sample is weighed.

c) Operations a) and b) are repeated two more times and calculated the average wet weight (BB).

d) Free absorbent capacity (CAC, g/g) is calculated as follows:

CAC = weight of artificial urine saturated foam /dry weight foam = [BB(g) - ST(g)]/ST (g)

IV) the Absorbent capacity under pressure (Desorption pressure) for each foam sample is defined as follows:

a) Chemical beaker 50 ml sieve placed on top of it, is placed under the center of the foot dial indicator placed on the sieve.

b) a Saturated sample is placed on the top sieve, making sure it is above the center of chemical glass, and the dial indicator is set for the application of pressure to the foam pattern.

c) the Goods are on display for the application of a pressure of 1.4 kPa to the sample;

d) After 15 min foam sample is weighed (BB, 1,4);

e) the same to 5.1 and 6.9 kPa to determine for them (VV, 5,1) and (BB, 6,9);

f) Using new samples, the operations a) to (e) are repeated two more times to determine the average wet weights after keeping the samples under different pressures.

g) Absorbent capacity under pressure (X - load, g/g) is calculated as shown.

X - load under a given pressure is the weight of the artificial urine in the wet foam (dry weight of the foam).

Capacity with 1,4 kPa.

X 1,4 (g/g) = 1,4 (g) - (g)/ (g)

The capacity (ability) when a 5.1 kPa

X, 5,1 (g/g) = 5,1 (g)- (g)/ (g)

The capacity (ability) at 6.9 kPa

X, 6,9 (g/g) = 6,9 (g) - (g)/ (g)

The size and absorbent capacity in ml of synthetic urine per gram of dry foam can be obtained by dividing the CAC and the values of the X-load on the weight of the artificial night, Geico approximately 1 g/ml.

C) a vertical Speed of absorption and the absorption performance of the vertical absorption.

The vertical speed of absorption and the absorption performance of the vertical absorption are measures of the ability of dry foam to absorb the liquid vertically from the tank. Measured the time required for the front of the liquid to soak in for 5 cm vertical length of the strip of foam, stobtsy the amount of liquid held foam strip on the height of the vertical absorption (for example, 11,4 cm) to obtain the absorptive capacity of the vertical absorption. Artificial urine, Geico, painted blue food dye, is used in the following methods of determining the vertical absorbing speed and vertical spilivaya absorbent ability. In this test, the material is equilibrated at 37oC and the test was conducted at the same temperature.

I) Preparation of the sample.

The strip of foam about 25 x 2 x 0.8 cm were prepared as test specific surface capillary suction.

II) a Container of liquid is placed on top of the laboratory of the lifting table, and the foam sample is fixed at one end so that it is vertically hung over capacity.

III) Then next to the foam sample is assigned to the line so that the bottom (0 cm) range was 1-2 mm above the bottom of the foam sample.

IV) the reservoir is filled to 3/4 painted with a solution of artificial urine.

2) the vertical Speed of absorption.

I) Capacity rises before the Foundation of the foam sample using laboratory lifting stratu rises until the liquid just touches the base line.

III) the Time taken for the front of liquid to achieve 5 cm, is recorded.

IV) Pins are given the opportunity to absorb until it reaches equilibrium (e.g., about 18 hours). Lifting table may require adjustment to maintain the sample immersed for 1-2 cm, and the sample must be protected to prevent evaporation.

3) Absorptive capacity (ml/g) on the vertical length of the foam.

I) Foam sample is removed and quickly placed on a nonabsorbent surface.

II) the Sample is immediately cut into individual pieces 2.54 cm using a very sharp tool, so as not to compress the foam sample, and each piece is weighed.

III) Most of the fluid is squeezed out of each piece and each piece is placed on an absorbent towel.

IV) Each piece is dried completely.

V) Each piece is then weighed and absorptive capacity for each slice is calculated on the basis of the difference between wet and dry weights.

For the purposes of the present invention is most well-defined parameter is ezinne voltage.

Adhesion voltage shown gidrogenizirovannye foam samples, absorbing the test fluid through the capillary suction is the product or the product of the surface tension of the liquid to be tested, multiplied by the cosine of the contact angle formed by the test liquid in contact with the inner surfaces of the foam sample. The adhesion tension can be determined experimentally by measuring the equilibrium height of the absorption due to capillary suction, showing two test specimens of the same foam, using two different test liquids. At the first stage of this procedure is determined by the specific surface of the foam sample, using ethanol as the test fluid, as described above for the specific surface of this section of the test Methods.

Then, the procedure of absorption by capillary suction procedure is repeated as with ethanol, except that as the test fluid used artificial urine, Geico and the test is performed at 37oC. the contact Angle of the artificial urine can be calculated as follows from the known values of specific powerco, grad.;

Mandis the mass of the absorbed liquid artificial urine, Geico, g;

G is the gravitational constant, component 980 cm/s2;

MN- the mass of dry foam sample, g;

u- is the surface tension of urine, Jaico of 65 Dyne/cm;

Sc- specific surface of the foam sample, cm2/g, as determined by the procedure of absorption of ethanol;

Ln- the length of the foam sample, see

When there is a surface-active substance (on the surfaces of the foam sample and/or experience in the moving fluid), the characteristic of the moving front of the liquid is determined using equation adhesion voltage (EN):

< / BR>
where

MT- weight of the test liquid absorbed by the foam sample;

G, LN, MNand Scare as described above. (See Hodgson and Berg, Jcoll Int. Sci, 121 (1), 1988, pp. 22-31).

When determining the adhesion tension for any given test fluid, no assumptions are not made in respect of the numerical values of the surface tension at any point in time, resulting in possible changes in the concentration of surfactants on poverhnosti adhesion voltage (JAYCO) is especially suitable, when viewed as a percentage of the maximum adhesive stress, which is the surface tension of the test fluid, for example, the maximum adhesive stress using artificial urine, Geico will be (655) (cos 0o)=(655) Dean/see

Preparation MDF foam absorbent materials, characteristics of such materials and their use in the disposable diaper shown by the following examples.

Example 1.

The preparation of the preferred MDF absorbent foam on pilot plant is shown with this example.

The emulsion preparation.

Calcium chloride (320 g) and potassium persulfate (48 g) dissolved in 32 l of distilled water. This forms the aqueous phase used for the formation of MDF emulsion.

In the monomer combination containing styrene (420 g), divinylbenzene (660 g) and 2-ethyl hexyl acrylate (1920), is added to the sorbitol of monolaurate (450 g in the form of SPANo80) and sorbitol of realeat (150 g, as SPANo85). After mixing, it will contain an oil phase, used for forming MDF emulsion.

When the temperature of the liquid of the order of 55 to 65oC Razdelna flows in the dynamic mixing chamber is achieved by using a finger of the mixer or agitator. At this stage, the corresponding finger stirrer comprises a cylindrical shaft with a length of 18 cm and a diameter of about 1.9 see the shaft has two series of 17 and two rows of 16 cylindrical fingers, each with a diameter of 0.5 cm, and directed radially outward from the Central axis of the shaft at a distance of 1.6 see Four rows are arranged at angles of 90oaround the circumference of the shaft of the agitator. The rows are perpendicular to each other, is displaced along the length of the shaft so that none of the fingers are perpendicular to each other, is not in the same radial plane passing through the axis of the shaft. Finger stirrer mounted in a cylindrical sleeve forming a dynamic mixing chamber, and the fingers mixer to form a gap of 0.8 mm with the wall of the cylindrical sleeve. The stirrer speed is 900 rpm.

Static mixer (20.3 cm length and 0.6 cm in outer diameter in x 0.43 cm inner diameter) was set to continue on a course of movement from the dynamic mixing chamber to facilitate formation of a back pressure. This helps maintain a dynamic mixing chamber containing a cylindrical sleeve with her finger stirrer, full. It also allows you to ensure with the oil phase, it turns out gradually. First flow rate adjusted to 3 o'clock by weight of the aqueous phase and 1 o'clock by weight of oil phase was entered in the dynamic mixing chamber with finger agitator. The ratio of water and oil phases increases for several minutes until, until the ratio of 12-13 hours of the aqueous phase to 1 tsp oil phase does not take place in a dynamic mixing chamber with a speed of 15 ml/s. Gradually, the speed of the oil flow is reduced so that the weight ratio of water phase/oil phase becomes close to 25:1. At this stage, the viscosity of the emulsion flowing from the static mixer falls. (Visually whitish mixture at this point it becomes more translucent).

Then the flow rate of oil phase further reduced to the point at which the weight ratio of water phase/oil phase is 30-33:1. Obviously, the emulsion at this stage is moving from a static mixer with the consistency of whipped cream and "sits" in consistency, resembling fat yogurt.

Polymerization of the emulsion.

At this point, the emulsion exiting the static mixer, ready for curing. The emulsion is fed in, essentially, a rectangular shape, made of Politica each of them will contain about 2000 ml of the emulsion, which must be cured.

Curing is performed by placing containing emulsion forms in the heat treatment furnace with a temperature of 60oC for 16 hours. After curing, the resulting solid polymerized foam material contains up to 98% of water and is soft and moist to the touch.

Flushing Vienna and hydrophilicity.

Wet cured foam material is removed from the curing form and subjected to further processing. The residual aqueous phase in the foam is removed by application of sufficient pressure to the foam material, or thin pieces of foam material for extrusion of at least 90% of the retained residual materials of the original aqueous phase. When the foam prepared in accordance with the above method, is compressed, the edges of the foam is not ekstragiruyut out and the cell is not broken. Rather foam, apparently, is compressed under the action of pressure in the Z-direction and then springs back into its original shape, or when the water is absorbed, or when heat is applied, as will be described in more detail below.

Then foam sample is washed for 20 seconds with water at 60oC, containing Mecosta mark joy, dissolved in water to a concentration of 5 g/l Active Hydrophilidae agents in the product contain a mixture of joy, including coconut alkylsulfate and ethoxylated coconut alkylsulfate anionic surfactant, as described in more detail in Pancheri, U.S. patent N 4316824, issued February 23, 1982 (see for details). During this processing, the foam springs back into its original shape.

The solution Joey used in the first washing, squeezed again, using pressure, and the foam is then processed by a second washing with a solution of joy at 60oC. the Second rinsing is required in order to leave a residual detergent in the foam, thereby making the inner surface of the foam is relatively hydrophilic.

Dehydration foam.

Then double-hydrophilisation foam again compressed to remove excess detergent solution from its porous structure. After that foam samples are dried by placing them in a drying oven for 12 hours at 60oC. After drying, the foam samples still cut if necessary, and they are ready for the next test or for inclusion in diaper products, described below in example 4.

2) Below in the direction from the mixing chamber using a static mixer length of 36.6 cm x 0.95 cm outer diameter.

3) Finger stirrer speed is 850 rpm min.

4) the Final weight ratio of water phase to oil phase is 31:1.

5) the curing Temperature used 66oC.

In this example, polymerized MDF foam hydrophilized treatment with an aqueous solution of calcium chloride as hydrophilizing agent. This solution hydrophilizing agent contains 1% by weight of calcium chloride and applied to the foam samples twice, in the same way as in example 1. After drying, the foam samples of this example, then cut as required for additional testing or for inclusion in diaper products of the type described below in example 4.

Example 3.

In this example, MDF foam materials prepared with ecost properties. The test for determining these properties is carried out using the techniques described in the previously mentioned U.S. patent N 4788225, or some of the procedures described earlier in the section test Methods.

The results of these tests are shown in table.

Example 4.

A disposable diaper is prepared using the design and components, shown disassembled in Fig. 4. This diaper contains thermobonded polypropylene top sheet 70, which is impervious to liquid polyethylene back sheet 71 and a two-layer absorbent core located between the top and back sheets. Dual-layer absorbent core contains stores/redistributing the liquid layer 72 having a modified form of the hourglass, including MDF foam type example 2, below the host liquid layer 73 in a modified hourglass-shaped. The top sheet contains two essentially parallel to the barrier cuff 74 with rubber bands. To the back sheet of the diaper is attached two rectangular electician element 75 waist. To each end of the polyethylene back sheet attached two elements 76 of the sheath waist, made of polyethylene. Tn outside to the rear sheet and serves as a mounting surface for the two elements 79 U-shaped type, which can be used for fastening the diaper around the user.

The receiving layer of the diaper core contains 93%/8% stacked while wet mixture of reinforced convoluted cellulose fibers and conventional non-amplified cellulose fibers. Reinforced twisted twisted cellulose fibers prepared from Kraft pulp southern soft wood with cross links formed glutaric anhydride to the value of 2.5 mol.% on a dry fibrous cellulose anhydroglucose basis. The fibers have a cross-connection in accordance with a dry process of cross-linking, as described by Dean, Moore, Ovens and Scoggin; U.S. patent N 4822453, issued April 18, 1989

These reinforced fiber is similar to fibers having the following characteristics:

Reinforced, braided, twisted cellulose (USIC) fiber.

Type - cross Kraft pulp from southern soft wood with glutaraldehyde to 1.41 mol.% on a dry fibrous cellulose anhydroglucose basis.

Dry density twist - 6.8 twists/mm

The wet density of the twist - 5.1 twists/mm

Retention of isopropyl alcohol - 24%

The show is Lithuania in combination with USIC fibers, made from pile Foley. These non-amplified cellulose fibers refined to 200 (Canadian standard of the degree of grinding of the pulp).

The receiving layer has an average dry density of about 0.07 g/cm3average density upon saturation with synthetic urine on the basis of the dry weight of the order of 0.08 g/cm2and the average specific weight of about 0.03 g/cm2. About 9.2 grams of the host liquid layer is used in the core of the diaper. The surface area of the receiving layer is in the order of 302 cm2. Its thickness is of the order of 0.44, see

Store/redistributing the liquid core layer of the diaper contains a modified form of an hourglass piece MDF foam of this type, as described above in examples 2 and 3. About 12 g MDF foam is used to form this storing/distributing layer having a surface area of 425 cm and thickness of about 0,826 see

Diaper having such a specific structure of the core, has a particularly desirable and effective use of the core to hold the incoming urine and, therefore, provides a very low accidental leakage when it is worn in the usual way young children.

Example 5.

Staff were asked to use one diaper at night and to record and report incidents of leakage at night each diaper. The results of the leaks received from all planusa, were then compiled and analyzed. As a result of this analysis it was possible to determine that in this group test of 13.1% diaper type example tech, while diaper Luvs tech 14,0%.

These group tests showed that the diaper using absorbent foam materials according to the present invention as storing fluid element provides a description of the leak, which is comparable with that of the commercially available control diaper, and the diaper according to the present invention contain less Aiguablava another type MDF foam material, are in the scope of patent claims of the present invention.

The emulsion preparation.

Calcium chloride (36,32 kg) and potassium persulfate (568 g) dissolved in 378 liters of water. This allows you to receive a stream of the aqueous phase used in the continuous process of forming MDF emulsion.

In the monomer combination containing styrene (1600 g), 55% technical grade divinylbenzene (1600 g) and 2-ethyl hexyl acrylate (4800 g), is added to the sorbitol of monolaurate (960 g SPANo20). After mixing this combination of material settles in for the night. The top layer is removed and used as oil phase in a continuous process for forming MDF emulsion. About 75 g of sticky residue is thrown.

When the temperature of the aqueous phase 48-50oC and the temperature of the oil phase 22oC separate streams of the oil and water phases are served in the dynamic mixing device. Thorough mixing of the combined streams in a dynamic mixing device is achieved by means of a finger-stirrers. At this stage, the corresponding finger stirrer comprises a cylindrical shaft length of the order of 21.6 cm and a diameter of about 1.9 see the Shaft, as described in example 1, satrom 0.5 cm and is directed outward from the Central axis of the shaft to a length of 1.6 see Finger impeller mounted in a cylindrical sleeve forming a dynamic mixing device, and the fingers have with the wall of the cylindrical sleeve gap 0.8 mm

Helical static mixer set lower in the direction from the dynamic mixing device to provide back pressure in the dynamic mixer and create an improved enabling components in the emulsion formed ultimately. Such a static mixer has a length of 35.6 cm and outer diameter of 1.3 see Applied static mixer model 070-821 firm TAN industries, modified sweetheart neckline 6.1 see

Combined, the mixing unit is filled with an oil phase and an aqueous phase in a ratio of 2 parts of oxen to one part oil. Dynamic mixing device is vented to remove air at the same time as it is fully populated. Flow rate during the filling consists of: oil phase - 1,127 g/s and the aqueous phase - 2,19 cm3/s

Once the installation is completed, the mixing begins in the dynamic mixer, stirrer which rotates at a speed of 1800 Rev/min the flow Rate of the aqueous phase then steadily increases over 130 sec to ve the place won with 51.75 kPa. Speed stirrer and then gradually and uniformly decreases to a value of 1200 rpm for 60 C. the Pressure drops to 3,05 kPa. At this point, the speed of the stirrer instantly increased to 1800 rpm then the back pressure of the system remains constant 31,05 kPa.

Polymerization of the emulsion.

The obtained emulsion flowing from the static mixer at this point is collected in boxes made of rubber for economical storage of chilled products model 3500. These boxes are made of polyethylene food stamps and have nominal dimensions of 45.7 x 66 x 22,9 see the True inner dimensions of these boxes is 38,1 x 58,4 x 22,9 see These boxes are pre-processed film from a solution containing 20% solution of SPANo20 in an equal weight of a mixture solvent of xylene and isopropanol. The mixture of the solvent evaporates, so that there is only one SPANo20. Forty-seven liters of emulsion is collected in each box.

Containing emulsion boxes are in a room whose temperature is maintained at 65oC for 18 h, to cause polymerization of the emulsion in the boxes with the purpose of obtaining a polymer foam material.

Flushing, the first material is removed from the curing boxes. The foam at this point contains 30-40 times greater than the weight of polymerized material (30-40X) residual aqueous phase, containing dissolved emulsifiers, electrolyte, and initiator. Foam material is cut using a sharp reciprocating blade for sheet thickness 0,89 see These sheets are then subjected to compression sequentially in 3 wringer rollers that gradually reduce the residual aqueous phase in the foam about 6 times (6X) by weight of polymerized material. Here the leaves, then saturated with 1% solution of CaCl2at 60oC, is compressed in the gap between the rollers to the content of the aqueous phase of the order of 10X, again saturated with a 1% solution of CaCl2at 60oC and then compressed with rollers to content of the aqueous phase in order of 10X.

Foam sheets containing about 10X that is essentially a 1% solution of CaCl2pass through the closing gap between the rollers, equipped with a vacuum slot. The last gap reduces maintenance solution of CaCl2about 5 times (5X) the weight of the polymer. The foam remains compressed after the last gap at a thickness of about 0.2 see Then the foam is dried in an oven with air circulation at a temperature of 60oC for which erial. To this point, foam sheets have a thickness 0,19 cm and have a good drape. The foam also contains about 11% by weight of residual sorbitol monolaurate emulsifier and about 5% by weight (anhydrous basis) residual hydrated calcium chloride as hydrophilizing agents. In the compressed state density of the foam is about 0.17 g/cm3. When extending to its free absorbent capacity (26.5 ml/g) in artificial urine Geico, expanded foam has a specific surface area of the capillary suction of the order of 2.24 m2/g, pore volume of order 29.5 cm3/g and an average cell size of about 15 microns.

Foam sheets, prepared as in example 6, are preferred "thin-until-wet" embodiment of the present invention, since these foam sheets are in the form of compressed foam material which expands upon contact with aqueous body fluids. After expansion of the foam materials are suitable for absorption of body fluids, which cause the foam to expand. Such preferred compressed foams are those that are made from non-hydrolyzed polymer material having a specific powerha material residual water-insoluble emulsifier and about from 0.1 to 7% by weight (anhydrous basis) of foam material toxicologically acceptable hygroscopic hydrated salt, which is preferably calcium chloride or magnesium chloride, as hydrophilizing agent.

In its compressed state such foam material will have a residual water content of from 4 to 15% by weight of polymerized material when it is stored at ambient conditions with a temperature of 22oC and 50% relative humidity. This content includes water as water of hydration, interacting with hygroscopic hydrated salt, as well as free water, absorbed in the foam. Such grips foam material will have a dry core density of from 0.08 to 0.3 g/cm3.

In its expanded condition such preferred thin-until-wet foam materials will have a capacity of about 12 to 100 ml/g and will have such a resistance to the deflection of the compression and limiting pressure of 5.1 kPa creates after 15 minutes, the deformation of the order of from 5 to 96% compression of the structure when it is saturated at 37oC to its free absorbent capacity of the artificial urine having a surface tension (655) Dean/see the Average cell size of such preferred thin-until-wet foam materials in the expanded state will be of the order of yuusha ability of artificial urine will be of the order of 9 to 29% of its dry base density in the compressed state.

Example 7.

Prepared diaper, generally similar in shape to that described in example 4, using as a store/redistributing the liquid layer sheet of thin-until-wet compressed absorbent foam described in example 7. This diaper receiving/distributing liquid layer containing reinforced twisted twisted cellulose fibers are used in amounts of about 13, the Thin-until-wet, store/redistributing the liquid layer is also used in a quantity of about 13 g

Diaper having such a specific form, demonstrates particularly desirable and effective use of the absorbent core to keep the incoming urine, and therefore provides very rare cases of leakage, when worn by infants in the usual way.

1. Absorbent article suitable for absorbing and retaining aqueous body fluids containing relatively impermeable to fluid back sheet and a polymeric foam material located between the rear sheet and place of receipt of fluid from the user device, the polymeric foam material obtained by the emulsion polymerization in the system "water-in-oil", p kouchkovsky comonomer and a bifunctional crosslinking agent, wherein the polymeric foam material has a magnitude of bending at least one cycle when saturation artificial urine at 37oC, and washed and dried the state has a hydrophilic flexible structure of interconnected open cells, containing a sufficient amount of residual hydrophilizing agent containing no irritating surfactant to convert the surface of the above structure in the hydrophilic, and this structure is used as the adsorbent pore volume from 12 to 100 ml/g, specific surface area when determining capillary suction from 0.5 to 5.0 m2/g, the resistance to deflection of the compression and limiting pressure of 5.1 kPa produces after 15 min exposure to the deformation of the compression component of from 5 to 95% volume of the foam structure when it is saturated at 37oC to its free absorbent capacity of the artificial urine having a surface tension (655) Dyne/cm, while the oil phase contains from 3 to 41 wt%, essentially water-insoluble monofunctional glassy monomer based on styrene, from 27 to 73 wt% of the monofunctional kauchukopodobnoe of co monomer selected from GD 8 to 30 wt% of a bifunctional forming a cross-link agent, selected from the group comprising divinylbenzene, divinylsulfide, one or more diacrylate acid esters of a polyhydric alcohol or a mixture thereof.

2. The product under item 1, characterized in that upon receipt of a polymeric foam material, the molecular ratio of monofunctional glassy monomer and kauchukopodobnoe of co monomer in the oil phase is from 1:25 to 1.5:1, and the oil phase comprises from 2 to 33 wt.% emulsifier component, soluble and suitable for forming a stable emulsion of water-in-oil", and from 0.2 to 40 wt.% the water-soluble electrolyte, and the mass ratio of the aqueous phase and oil phase, forming the emulsion ranges from 12:1 to 100:1, and the structure of the polymeric foam material is hydrophilic to such an extent that it exhibits adhesion voltage from 15 to 65 Dyne/cm, when it absorbs artificial urine having a surface tension (655) Dean/see

2. The product under item 2, characterized in that the oil phase contains an emulsifier selected from the group comprising ether of sorbitol and fatty acid ester of polyglycerol and fatty acid esters of polyoxyethylene and fatty acids, and combinations thereof, and the aqueous phase includes one or more p is different, however, that hydrophilic flexible structure of the porous polymer material in the place of use as the absorbent material has a density in the dry state of from 0.01 to 0.08 g/cm3the cell size of 5 to 100 μm, the recovery of deflection compression such that after compression duration 1 min structure recovers within 1 min of at least 85% of its original thickness when it is being in a dry state or when the saturation patterns to free absorbent capacity of the artificial urine having a surface tension (655) Dyne/cm at 37oC, followed by compression with a duration of 1 min structure recovers within 1 min of at least 75% of its original thickness, the equilibrium of the free absorbent capacity at 37oC at least 12 ml of synthetic urine per 1 g of dry polymer foam material, the absorbent capacity with synthetic urine under the action of the limiting pressure of 5.1 kPa for 15 min at 37oC at least 5% of its equilibrium free absorbent capacity, speed vertical absorption at 37oC that artificial urine absorbed by the vertical length of the polymer foam A least 10 ml of synthetic urine per 1 g of polymer foam material during the height of the vertical absorption 11,4 see

5. Product according to any one of paragraphs.1-4, characterized in that the polymer foam material that essentially does not contain polar functional groups in its polymer structure and contains from 0.1 to 100 wt.% residual hydrophilizing agent selected from not irritate the skin surface-active substances and logogeriatrics inorganic salts.

6. Product according to any one of paragraphs.1-5, characterized in that it further comprises, essentially permeable to fluid top sheet, and the polymer foam material is an absorbent core located between the relatively permeable to the fluid in the rear sheet and essentially permeable to fluid top sheet, absorbent core contains an additional component of cellulose fibers and/or particles or fibers of polymeric gelling agents or he has a multilayer structure with a top layer containing fibers of wood pulp or reinforced twisted twisted cellulose fiber up to 10 wt.% particles of polymeric gelling agent, and with the bottom layer containing the foaming material.

7. Product according to any one of paragraphs.1-6, characterized in that it is made in the form of a disposable diaper, in which the leaf has the same length on the other surface of the core, the opposite surface is covered with a top plate, and has a width larger than that of the core, to form the back sheet side edge portions protruding beyond the core, the absorbent core has the shape of an hourglass.

8. Absorbent article suitable for absorbing and retaining aqueous body fluids containing relatively permeable to fluid back sheet and a polymeric foam material located between the rear sheet and place of receipt of fluid from the user device, wherein the polymeric foam material is compressed polymeric foam material which upon contact with aqueous body fluids expands and capable of absorbing liquids, the polymeric foam material has a dry hydrophilic flexible non-hydrolyzed structure of mutually connected open cells having a specific surface capillary suction from 0.5 to 5.0 m2/g and containing additionally includes from 0.5 to 20 wt.% residual insoluble in water emulsifier and 0.1 to 7 wt.% toxicologically acceptable hygroscopic hydrated salt, the structure is in its compressed SOS/cm3and in its expanded state pore volume from 12 to 100 ml/g, the resistance to deflection of compression such that the limiting pressure of 5.1 kPa creates after 15 min exposure to the deformation of the compression ratio from 5% to 95% of the volume of the foam structure when it is saturated at 37oC to its free absorbent capacity of the artificial urine having a surface tension (655) Dyne/cm and a density in the dry free state when saturated to its free absorbent capacity of the artificial urine from 9 to 28 of its specific density of dry compressed state.

9. The product under item 8, characterized in that it further comprises, essentially permeable to fluid top sheet, and the polymer foam material is an absorbent core located between the relatively permeable to the fluid in the rear sheet and essentially permeable to fluid top sheet, absorbent core contains an additional component of cellulose fibers and/or particles or fibers of polymeric gelling agents or has a multilayer structure with a top layer containing fibers of wood pulp or reinforced twisted twisted cellulose fiber and up to 10 wt.% particles of polymer Helly 9, characterized in that it is made in the form of a disposable diaper, in which the top sheet has the same length with one surface of the absorbent core, the back sheet has the same length on the other surface of the core, the opposite surface is covered with a top plate, and has a width larger than that of the core, to form the back sheet side edge portions protruding beyond the core, the absorbent core has the shape of an hourglass.

 

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