Multilayer casing for food products with inorganic particles in outer layer
FIELD: packing industry.
SUBSTANCE: casing is produced by the coextrusion of at least two layers including the outer layer (Z). At least one layer which is not an outer one (Z) contains more than 50 wt % of thermoplastic components on the (co)polyamide(s) basis. The outer layer (Z) contains more than 50 wt % of thermoplastic components and inorganic particles distributed in them with at least part of the particles having the diametre of the equivalent sphere exceeding 20 mcm. At least one of the layers (not the outer one (Z)) performs the carrying function.
EFFECT: as per their appearance and roughness the obtained casings for food products are similar to the collagen, protein, reinforced with fibers cellulose and natural casings.
14 cl, 1 tbl, 4 ex
The invention relates to a thermoplastic multilayer casing for food products, in which the layer located on the outer surface comprises at least one inorganic solid substance in the outer layer, which are distributed in at least one of thermoplastic synthetic material. This surface layer has a high degree of roughness and low gloss. The film thus remains opaque, similar to collagen membrane in appearance and to the touch, and keeps very good roughness. Non-edible collagen casings will be called collagen sausage casings.
Wrappers for food products, especially sausage casings, traditionally made from natural gut, collagen fibers, protein fibers, reinforced with cellulose fibres or textiles. These wrappers are still on the world market a larger share, in particular, for high-grade sausage. In second place is the shell of thermoplastic synthetic material, in particular a shell made from polyamide or combined systems polyamide-polyolefin. Most thermoplastic membranes, in turn, upon receipt oriented by stretching, which leads to the ability to heat shrinkage and better mechanical properties. However, thermoplastic look about the shell still very unnatural. In addition, thermoplastic shell is usually so smooth that they are very little resemblance to the naturally structured surface collagen casings and, in addition, when the content they often slip from the hands.
Collagen and protein sausage casings get very expensive and polluting the environment by way of the skins of bovine animals: skin tissue is separated until the fibrils acids, such as lactic acid; high-viscosity mass ekstragiruyut, slowly and densely beset with gaseous ammonia or ammonium hydroxide and utverjdayut. In this case, when drying occurs crosslinking (curing)to give the products a sufficient stability, so that the cooking process has not been a significant loss of strength. However, because of the antibiotics of natural casings as protein sausage casing, is less and less accepted by the end users. In addition, there are legal restrictions. Therefore, a desirable alternative to the above shells. Cellulose casings, even shell, reinforced fibers, solve this problem only to a limited extent. The retrieval method is not less costly and less harmful to the environment than the method of obtaining collagen and collagen sausage casings.
The big advantage of thermoplastic who wrappers for food products is simple, inexpensive getting. However, the end user often has a bias against the sausages in these shells. Natural synthetic material is very shiny surface often gives the impression of lower quality products. Still the visual impression could be improved, if only to make them matte by using coating, but not so much that managed natural imitation of collagen, a protein or, fiber-reinforced cellulose casings. I should add to this the poor quality of the sausages to the touch, when the surface of the synthetic material soaked with moisture or grease.
The shells of natural gut and, in particular, reinforced by cellulose fibers or collagen fibrous consistency contributes roughly structured rough surface. The consumer, who is such a kind familiar to many decades, associated with high quality or traditional sausages.
From the document DE 4141292 A1 known single-layer, transparent, duono-oriented tubular casings for food products based on polyamide, which contain point pigments with a particle size of from 0.01 to 15 μm. Point the pigments should primarily contribute to a reduced tendency to block.
In document WO 02/00026 A1 disclosed a multilayer, duono-oriented R is Kanye shell of synthetic material, which consist of at least one polyamide and, if necessary, of the layer containing the polyolefin containing buried him nanoparticles in the proportion of from 0.1 to 4 wt.%. Under nanoparticles are meant, in particular, layered silicates, the length of which in any dimension less than 100 nm.
Described films have high transparency and act as an improved barrier to oxygen.
In document WO 01/03508 A1 presents a wrapper for food products, where on the outside cellulose casings for food products coated using aqueous suspensions based on cationic resin and silicon dioxide. The particle size of the inorganic substance is, as a rule, from 0.1 to 25 μm, and the proportion may vary from 20 to 83,3 wt.%.
Highly permeable composite film described in the publications US 2003/0077471 A1 and WO 03/020513 A1. These films consist of at least two layers: the inner layer, which consists, generally, of the polyolefin and the inorganic filler, and from the outer layer, which contains a mixture of at least two incompatible polymers, preferably atactic polypropylene and low density polyethylene or polystyrene and adhesion promoter. By focusing this layered combination creates microcracks, which are responsible for the high permeability of the lenok. Apply these materials especially in the field of hygiene, for example baby diapers.
In the cited publications natural appearance and the corresponding surface structure, i.e. the regulation of special appearance and surface collagen casings, are not the subject of the greatest interest. Entered inorganic substances are there primarily for the best tropicalista in the filling process, in particular, manually, to create a reduced tendency to block wound products, to achieve improved barrier to oxygen or particularly high permeability. Fine particles also do not contribute sufficient roughness and tropicality.
In addition, sometimes the quality of the materials used in the membranes according to the invention, applied to other polymer matrix, or a combination of different polymers.
Therefore, the task is to obtain a multilayer casings for food products, which can be made so that it could be largely or completely, the appearance and roughness of natural, collagen, protein or reinforced fibers cellulose casings.
The problem is solved by a multilayer coextruding thermoplastic casings for food products, which manufactured the and of the at least two layers, including the outer layer (Z), and at least one layer which is an outer layer (Z), contains more than 50 wt.% thermoplastic components based on (co)polyamide(s) and outer layer (Z) contains more than 50 wt.% thermoplastic components and dispersed therein inorganic particles, at least part of which has a diameter equivalent to a sphere than 20 microns.
The compositions of the individual layers are selected in accordance with their function. In one preferred embodiment, outer layer (Z) is at least one layer with the function of the mechanical substrate.
The shell according to the invention for food can have, in particular, 2, 3, 4, 5, 6, 7, 8, 9 or 10 layers in series. Therefore, this shell may in some cases the implementation to have one outer layer (Z), as well as one, two, three or four other layer. In preferred embodiments, the implementation of the sheath according to the invention has in addition to the external layer (Z), in particular one, two, three or four other layers, which are the functional layers, such as layers of type (A), (B) or/and (C). Individual layers may (but not obliged) to be clearly separated from each other. Two adjacent layer can have a smooth transition or/and to have a surface boundary between two layers with irregularly varying roughness.
Shell food who's products preferably is tubular, it is expedient with a circular cross-section, and flexible. It can be used in particular as sausage casings, but also as a wrapper for dairy products and other food products. Wrapper for food products can be used, for example, in the form of segments, corrugated shells, natural intestinal membranes, for example, oiled or/and in the form of a circle.
Compared with the prior art casings according to the invention differ primarily in appearance, similar to collagen membrane, the protein shell, reinforced fibers cellulose membrane or/and natural shell, which is achieved thanks to a multilayer structure, in particular of synthetic thermoplastic polymers, and is also located on the outer surface of the layer (Z) of a mixture of at least one inorganic particulate material and at least one thermoplastic synthetic material.
Under thermoplastic materials in the framework of this proposal are understood, in particular, such materials, which consist mainly of typical thermoplastic polymers. Many of these polymers have higher application temperature and below the melting interval smoother transition region or/and (in particular, in the case of at least partially crystalline polymers) melting point.
Externally the th layer (Z) preferably also contains inorganic particles with a diameter equivalent to a sphere more than 25 μm or more to 30 μm, particularly preferably 35 μm or more to 40 μm, totally more preferably 45 μm or more to 50 μm, in particular more than 55 μm, 60 μm or more, especially more than 65 μm or more and 70 μm. However, in some embodiments, the implementation can occur inorganic particles with a diameter equivalent to a sphere more than 75 μm, 80 μm, 85 μm, 90 μm, 95 μm or more than 100 μm.
As the inorganic powdered substances, which, in particular, can be added, preferably in the outer layer (Z), among other suitable the following.
1. Fibers of glass, such as glass fibres, glass filaments and/or staple fibre glass.
2. Short fibers of mineral wool, for example, basalt wool, slag wool or mineral wool fibers.
3. Fillers or reinforcing materials of carbonate(s), such as chalk, limestone powder, calcite, precipitated calcium carbonate, magnesium carbonate, barium carbonate, dolomite or/and other mixed carbonates.
4. Sulfates, such as barium sulfate or calcium sulfate.
5. Silicates, such as talc, pyrophyllite, chlorite, horn blende, mica, kaolin, clay, wollastonite, mineral flour, such as slate flour, precipitated or natural silicates containing alkali and/or alkaline earth metals, silicates with som is Kimi cations, as, for example, silicates MgFe, AlMg, CaAl, NaAl or KAl, feldspars, Deputy feldspar, mullite, zeolites or/and metasilicate Ca.
6. Silicic acid of various types, for example, quartz, fused quartz, cristobalite, ground or crushed material substances with a very high content of SiO2as kieselguhr or/and Nabulsi silica, precipitated or pyrogenic silica, glass powder, pumice powder, perlite, finely ground Frit or glass (micro)spheres or grains of silicate as solid balls, hollow balls and/or fragments thereof.
7. Oxides, such as aluminum hydroxide, aluminum oxide, magnesium hydroxide, magnesium oxide, titanium oxide, silicon dioxide.
8. More like carbon fiber, particles of carbon black and/or graphite.
In particular, the inorganic particles are composed mainly or entirely of particles on the basis of aluminum oxide, carbonate, phosphate, silica, silicate, sulfate, minerals and/or vitreous material.
The surface of the inorganic particles can be modified, for example, an adhesion promoter, which can be achieved high compatibility with the surrounding synthetic matrix, or to be painted. In the polymer matrix of the inorganic particles in the known cases, there may be a cavity, in particular, when extruding.
Large neorg the organic particles in the outer layer (Z) is especially useful for roughness and tropicalista shell. The fraction of inorganic particles of the medium and/or small size can be, in particular, to strengthen the matte appearance and create a microstructure. This can be a mixture of particles of different shapes. The share of large primary particles biaxial stretching, for example, plates, preferably small or (almost) equal to zero.
In some embodiments, the implementation of at least part of the inorganic particles is preferably in a substantially isometric, linear, needle-like or fibrous form. In this case, depending on the circumstances, it is preferable that most of the particles, in particular large, had preferred this form. It is preferable to use the mixture of inorganic particles, which has essentially isometric particles, or substantially linear, acicular or fibrous particles, in particular, in the range of ratios of from 5:95 to 95:5, preferably in the range of from 15:85 to 95:5, particularly preferably greater than 25:75 or greater than 35:65, or less than 75:25, or less than 65:35, preferably completely, about 45:55, or about 55:45. The latter can be partially or fully, slightly or strongly ordered. But they can also be contained preferably in an external layer (Z) irregularly that it was impossible to distinguish the predominant n the Board.
Inorganic particles in the outer layer (Z), first of all particles in the form of fibers or/and large, essentially isometric particles give the shell a very natural matte look and good roughness to the touch. This ensures that the surface receives a small surface roughness, which can regulate the type, number of particles and the distribution of particle size. In addition, the share of these particles can affect the ability of the shell to collapse into the ring. In addition, inorganic particles act as active filler, making the stability of the caliber of the filled material (change in diameter) compared to the unfilled material is significantly increased.
The mass ratio between the inorganic particles and synthetic materials across the membrane for food products is preferably from 0.01:99,99 to 40:60, particularly preferably at least 0.05 to:99,95, respectively, up to 30:70, most preferably at least 0,1:99,9, respectively, up to 20:80, in particular at least 0,3:99,7 or at least 0,5:99,5, respectively, up to 16:84, until 12:88, or up to 8:92, primarily at least 0,8:99,2 or at least 1:99, respectively, up to 6:94, or even up to 4:96.
The mass ratio between the inorganic particles is mi and synthetic materials in the outer layer (Z) or/and in the other layer (in each case per layer) is preferably from 0.1:to 99.9 to 50:50, especially preferably at least 0,3:99,7, respectively, up to 40:60, most preferably at least 0,5:99,5, respectively, up to 30:70, in particular at least 0,75:99,25 or at least 1:99, respectively, up to 25:75, or up to 20:80, especially at least 1.5:98,5, or at least 2:98, respectively, up to 15:85, or even up to 10:90.
As a synthetic component(s) in the outer layer (Z) of the shell in principle fit all thermoplastic polymers, such as thermoplastic polyurethane, thermoplastic polyetherurethane, aliphatic (co)polyamide, aliphatic or partially aromatic (co)polyester, polyetheretherketon, along with this, if necessary, vinyl copolymers, for example copolymers of ethylene with vinyl acetate. From polyurethanes preferred preaddukta that receive, for example, by reaction of diisocyanate (TDI), isophorondiisocyanate or/and hexamethylenediisocyanate with poly-1,2-propane diol (polypropylenglycol, PPG) or/and preferably poly-1,4-butanediol (polytetramethylene, PTMG). From polyamides are particularly suitable PA6, PA, PA, PA6/66, PA6/12. Of polyesters are particularly preferred polylactide, polycaprolactone, copolymers alifaticheskih diols with aliphatic dicarboxylic acids and terephthalic acid, as well as polybutyleneterephthalate. Often the composition of the outer layer (Z) is a mixture of one or at least two thermoplastic polymers.
The proportion of thermoplastic components in the outer layer (Z) is more than 50 wt.%, preferably more than 55 or more than 60 wt.%, especially preferably more than 65 or more than 70 wt.%, if necessary, even more than 75, 80 or 85%.
The layer (Z) can also contain additional organic substances such as carbohydrates, including starches, and proteins, or/and, if necessary, additives such as other high or/and low molecular weight components, as a softener, such as glycerin, glycol, ester of carboxylic acid and of glycerol, ester of phthalic acid or stabilizers, bactericidal and/or fungicidal substances.
Color and color change coextruding wrappers for food products can be adjusted by adding inorganic or/and organic dyes and/or inorganic and/or organic pigments in the layer (Z) or/and in the next layer and, for example, varies by different amounts and different homogeneity or structuring.
The outer layer (Z) is made preferably of a homogeneous or substantially homogeneous, or is essentially homogeneous, if not to take into account the distribution of inorganic and/or organic particles or/and the distribution of inorganic and/or organic dyes or/and the difference of color.
The outer layer (Z) preferably contains at least 0,05% vol. or at least 0.2 vol% inorganic particles with a diameter equivalent to a sphere of at least 20 μm, respectively, the volume of particles of at least 4189 μm3especially preferably at least 0,05% vol. or at least 0.2 vol% inorganic particles with a diameter equivalent to a sphere of at least 25 μm, respectively, the volume of particles of at least 8181 μm3or at least 0,05% vol. or at least 0.2 vol% inorganic particles with a diameter equivalent to a sphere of at least 30 μm, respectively, the volume of particles of at least 14137 μm3absolutely preferably at least 0,05% vol. or at least 0.2 vol% inorganic particles with a diameter equivalent to a sphere of at least 40 μm, respectively, with the volume of particles of at least 33510 μm3or at least 0,05% vol. or at least 0.2 vol% inorganic particles with a diameter equivalent to a sphere of at least 45 μm, respectively, the volume of particles of at least 47713 μm3in particular at least 0,05% vol. or at least 0.2 vol% inorganic particles with a diameter equivalent to a sphere of at least 50 μm, respectively, the volume of particles of at least 65450 μm3or at least 0,05% vol. or at least 0.2 vol% reorganizes is their particle diameter of the equivalent sphere at least 55 μm, accordingly, displacement of particles at least 87114 μm3first of all, at least 0,05% vol. or at least 0.2 vol% inorganic particles with a diameter equivalent to a sphere of at least 60 μm, respectively, the volume of particles of at least 113097 μm3or at least 0,05% vol. or at least 0.2 vol% inorganic particles with a diameter equivalent to a sphere of at least 70 μm, respectively, the volume of particles of at least 179594 μm3.
The shell according to the invention the combination of inorganic particles of the outer layer (Z), or at least its particles having essentially isometric form, have a distribution along the diameter of the equivalent sphere is preferably at least in the range from 20 to 40 μm, particularly preferably in the range of from 25 to 50 μm, from 30 to 60 microns, or from 40 to 70 μm, most preferably in the range from 50 to 80 μm, 60 to 90 microns, or from 70 to 100 microns. In addition selected, the above-mentioned interval here may also have smaller particles than the particles of the specified size.
The combination of inorganic particles of the outer layer (Z) in terms of embodiments preferably contains at least 10 vol.% of the total volume of the inorganic particles, the particles essentially isometric forms, particularly preferably at least 30 vol.%, totally a preference for the equipment at least 50 vol.%, in particular at least 70 vol.%.
The combination of inorganic particles of the outer layer (Z) in terms of options for the implementation of contains (if such forms of particles are within a certain range), preferably at least up to 2% vol. of the total volume of the inorganic particles, the particles essentially fibrous, needle-like or linear form, particularly preferably at least 5 vol.%, quite preferably at least 10 vol.%, in particular at least 20%vol.
The outer layer (Z) contains preferably at least 0.5 wt.% inorganic particles, particularly preferably at least 1 wt.%, quite preferably at least 2 wt.%, in particular, at least 4 wt.%, first of all, at least 6 or at least 8 wt.%.
If, however, the composition of the outer layer (Z) add a fraction of fibers, the layer (Z) in terms of embodiments preferably contains at least 0.1 wt.% fibrous inorganic particles, particularly preferably at least 0.5 wt.%, quite preferably at least 1 wt.%, in particular at least 2 wt.%, first of all, at least 4 wt.%.
To achieve the tactile experience of natural, collagen, protein or reinforced fibers cellulose casing preferably installs the following, used is i.i.d. in each case at least 5 measurements, the degree of surface roughness of the outer layer:
Ra≥0.8 μm, particularly preferably Ra≥1,0 μm, preferably completely Ra≥1.2 microns, in particular Ra≥1.4 µm, primarily Ra≥1.6 ám and
Rz≥5.0 µm, particularly preferably Rz≥to 6.0 μm, preferably completely Rz≥7.0 µm, in particular Rz≥8.0 µm, primarily Rz≥9,0 microns or/and
Rmax≥to 6.0 μm, particularly preferably Rmax≥7.5 μm, preferably completely Rmax≥9 μm, in particular Rmax≥to 10.5 μm, especially Rmax≥12 μm.
In particular, the average degree of roughness are Ra≥1,8 µm, Ra≤5.0 µm, Rz≥10 ám, Rz≤35 μm, Rmax≥13 microns or/and Rmax≤45 microns. First of all, the average degree of roughness are Raabout 2, 2,2, 2,4, 2,6, 2,8, 3,0, 3,2, 3,4, 3,6, 3,8, 4,0, 4,2, 4,4, 4,6 4.8 μm, Rzabout 11, 12, 13, 14, 15, 16, 17, 19, 21, 23, 25, 27, 29, 31 or 33 μm or/and Rmaxabout 14, 15, 16, 17, 18, 19, 20, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41 or 43 mm.
To achieve the optical impression of natural, collagen, protein or reinforced fibers cellulose casing should preferably be installed following averaged in each case at least 5 measurements, indicators of surface gloss of the outer layer, which is measured when the angle of radiation 60°:
figure Shine ≤65, particularly preferably ≤55, preferably completely ≤45, in particular ≤35, primarily ≤25. The lower the figure the Shine, the more matte looks the outer layer (Z).
In particular, the average of glitter make up≥0,5, ≥1, ≥2, ≥4, ≥6 or ≥8 or≤24, ≤22, ≤20, ≤18, ≤16 or ≤14. First of all, they make up about 1, 3, 5, 7, 9, 11, 13, 15, 17, 19 or 21.
Preferably at least one additional layer, in addition to the external layer (Z), is typical of synthetic material mechanical properties of the shell, as, for example, high tensile strength and high elasticity. This at least one layer is often the bearing layer of the shell. In certain cases at least one layer, in addition to the external layer (Z), contributes to the high gas and paronepronitsaemost. In some embodiments, the external layer (Z) can also be of high gas and vapour barrier.
These additional, along with the outer layer (Z), the layers preferably contain synthetic materials based on (co)polyamide, polyolefin, copolymer of ethylene vinyl alcohol (EVOH), (co)polymer vinylidenechloride or/and (with)polymerizate with the properties of the adhesion promoter. Especially preferably, at least one of the layers of the shell had a share based on (co)polyamide is at least 50 wt.% what if at least 55 wt.%, or at least 60 wt.%, quite preferably at least 65 wt.%, or at least 70 wt.%, or at least 75 wt.%, quite preferably at least 80 wt.%, or at least 85 wt.%, or at least 90 wt.%, in particular at least 95 wt.%, or at least 98 wt.% or even about 100 wt.%. This layer may also be an outer layer (Z) and can optionally be enriched (co)polyamide. However, it is often preferable to another layer, and not the outer layer (Z), have the function and composition of the layer (A). Itself, one outer layer (Z) in many cases because it contains a relatively large inorganic particles is not bearing layer, as it often does not reach the relevant properties.
Enriched (co)polyamide layers (hereinafter abbreviated as A) can contain one or more aliphatic polyamides and aliphatic copolyamids, and if necessary, some partially aromatic polyamides and partially aromatic copolyamids. Their examples are:
|Aliphatic polyamides||PA6, PA, PA|
|Aliphatic copolyamids||PA/6, PA6/66, PA6/69, PA6/9, PA6/10, PA6/12, simple polyetherimide complex is reafirmed, preferability, polyamidoamine, block simple polyetherimide|
|Partially aromatic polyamides||PA6-I, nylon-MXD6 (polycondensate of m-xylylenediamine and adipic acid)|
|Partially aromatic copolyamids||PA6-I/6-T, PA-6/6-I.|
Particularly preferred components are PA6, PA, PA, PA6/66, nylon-MXD6 and PA6-I/6-t Especially preferred mixtures contain at least two such polyamide. The proportion of partially aromatic (co)polyamides is preferably not more than 40 wt.% from layer (A), particularly preferably not more than 25 wt.%.
In addition, the layer (A) may also contain other polymers such as olefinic copolymers, as EMAA (a copolymer of ethylene and methacrylic acid)ionomers based on them, EVOH or soluble (hot) water synthetic polymers, such as polyvinyl alcohol, optionally partially or completely saponified, copolymers of vinyl alcohol and propen-1-ol, polyalkylene glycols, polyvinylpyrrolidone, copolymers of vinylpyrrolidone with at least one Monomeric link with α,β-olefinic-unsaturated, polymers of N-vinylamides or (co)polymers of acrylic acid and/or acrylamide. The share of other polymers is preferably not is m ore than 35 wt.% from layer (A). In addition, if necessary, the layers (A) may optionally contain pigments and/or other typical synthetic materials additives.
In some cases, it is preferable that at least one layer acted as a barrier to water vapor. This can be achieved with at least one polyolefin layer. Polyolefin layers (hereinafter abbreviated as B) are usually essentially of polyethylene, polypropylene and/or of copolymers with units of ethylene, propylene and α-olefin, preferably with the number of C atoms from 4 to 8 or/and from dienes. As comonomeric links are also possible functionalityand vinyl monomers as vinyl acetate, (meth)acrylic acid and an ester of (meth)acrylic acid. In particular, suitable C2/C3- or/and C2/C8copolymers. Layers (B) are primarily a function of the moisture barrier, as polyolefins typically have a very low permeability. In addition, the layers (B) may also contain dyes and/or fine-grained pigments, as they typically are used for coloring or for protection from UV. Therefore, these layers can also be painted.
To achieve good barrier to oxygen and other gases, if necessary, can be added layers of synthetic materials with an appropriate barrier effect (also called C). On the walking for the synthetic materials are copolymers of ethylene and vinyl alcohol, optionally partially or fully saponified (EVOH), and copolymers of vinylidenechloride and, for example, vinyl chloride or methyl acrylate as the co monomer (PVDC). These polymers can also be blended with additives, such as plasticizer, and other polymers, as, for example, copolyamids or ionomers. Layers (B) or (C) is also usually have a thermoplastic nature.
Note that the layers corresponding to (A), (B) and (C) in the multilayer film, sometimes do not adhere well to each other. Good adhesion is achieved by additionally introduced at least one layer of adhesion promoter (HV) in the form of intermediate or inner layer, which upon receipt of the films, for example, coextrusions, stick together with the two adjacent layers. Suitable adhesion promoters are, in particular, grafted or/and linear copolymers, these copolymers may include more than two monomers, with units of ethylene and/or propylene, as well as components from the group consisting of (meth)acrylic acid ester (meth)acrylic acid, vinyl acetate and maleic anhydride. Particularly preferred, among others, polyethylene grafted maleic anhydride (LLDPE-g-MAA)copolymers of ethylene and acrylic ester, and copolymers of ethylene and vinyl acetate (EVA). These polymers in HV-layers may be contained in otdeleniia in the mixture. Additionally HV-layers may contain other polymers, such as polyethylene, and/or other additives, and pigments.
HV-layers can also be omitted, if between the functional layers there is sufficient internal cohesion, which, for example, often exists between the polyamide and some EVOH, or due to the fact that the component - adhesion promoter - vmeshivat in components, for example, the boundary layer (B).
The difference in the structure, the structure and/or composition between the individual layers can always independently from each other be from layer to layer is less than or noticeable expressed. The transitions between the individual layers, can be, independently from each other, markedly or slightly bent from the border to the boundary layer or to be smooth. The boundary layer can be essentially completely smooth or, in particular, due to the larger neighbouring particles or clusters of particles, rather rough, and in this case, if necessary, also with strong fluctuations in the thickness of the individual layers. Particularly preferably, the outer layer (Z) has at least one layer with the function of mechanical media.
The outer layer (Z) can be combined with other these types of layers to produce different multilayer structures. Always is essential that the layer (Z) was located on the outer surface of the sheath, and beneath it was on ENISA least one layer with the function of mechanical media. The preferred structures of the layers are (abbreviations see above):
|The outer side of the sleeve:||The inside sleeves|
Especially preferred structure according to the points 4), 6), 12), 15), 16), 17) and 19).
Preferably the casing for food products, in addition to the external layer (Z)has at least one layer selected in the layers (a) fraction of thermoplastic substances based on (co)polyamide(s), layer (B) fraction of the polyolefin(s) and layer (C) with barrier effect for oxygen and other gases, and optionally at least one layer of HV as an intermediate layer of adhesion promoter and/or an inner layer of adhesion promoter.
Preferably, the shell for the food contains at least one layer (a) fraction of thermoplastic substances based on (co)polyamide(s) and one outer layer (Z), and optionally at least one layer (B) fraction of the polyolefin(s), optionally also at least one layer (C) with barrier effect for oxygen and other gases or/and optionally also at least one layer of HV as an intermediate layer of adhesion promoter and/or as an internal layer the adhesion promoter.
Preferably the casing for food products, in addition to asnago layer (Z), has at least one layer (a) fraction of thermoplastic substances based on (co)polyamide(s) and at least one layer of HV as an intermediate layer of adhesion promoter and/or an inner layer of adhesion promoter.
Preferably the shell to get food joint extrusion, and it is made in at least two layers, and it contains at least one layer (a) fraction of thermoplastic substances based on (co)polyamide(s) and one outer layer (Z), and optionally at least one layer (B) fraction of the polyolefin(s), optionally also at least one layer (C) with barrier effect for oxygen and other gases or/and optionally also at least one layer HV as an intermediate layer of adhesion promoter and/or an inner layer of adhesion promoter.
Obtaining mixtures of thermoplastic synthetic matrix and inorganic particles for the layer (Z) can be conducted, for example, at the stage of compounding by a known method. This can be connected coextrude as extrusion sleeve. The above additives are added, if necessary, also during the processes of subsidence or mixing and inserted into the outer layer (Z) mostly uniformly or completely uniformly. During extrusion of the sleeve all the layers fo moutse at the same time.
Getting casings for food products according to one of the above structures is carried out by coextrusion and preferably with the subsequent blowing sleeves or biaxial stretching. Appropriate specialist known.
The mixture of inorganic particles and a synthetic matrix, and also provided other polymers or mixtures usually melted in separate extruders and plastificator, and then brought together in a heated annular mouthpiece coextruder. Facing annular cast film may or direct blow in film sleeve, or be fed to a process biaxial stretching, if necessary, followed by heat setting. In the latter process the film melt utverjdayut by rapid cooling to amorphous primary sleeve and then it doesno pull by reheating, often up to about 80°C, using an air cushion enclosed between two pairs of wringer rolls. Subsequent heat setting may be carried out so that an elongated sleeve carried out through the following heating zone, if necessary, with the stabilization of the second air bag. In this way it is possible to reduce the tendency of the shell to thermal shrinkage to a reasonable practice values, which typically comprise about 5-20% in length and width, measured at 80°C.
Examples and comparative examples
Further properties of the membranes according to the invention will be explained on the selected examples of implementation.
Example 1. Cristobalite and PA 66, blow sleeve.
Using co-extrusion technology through three single-screw extruders and extrusion connected ring tip was obtained three-layer blow molding of the sleeve
- inner layer consisting of a polyamide PA (®Ultramid A5),
- middle layer, consisting of 80 wt.% polyethylene LDPE (®Lupolen 3020D), mixed with 20 wt.% LLDPE grafted MSA, as adhesion promoter (®Admer NF358E) and
- outer layer consisting of obtained on a conventional twin-shaft mixer compound of 93 wt.% polyamide PA (®Ultramid A5) and 7 wt.% cristobalite (®Silbond 006 MST).
Full wall thickness of the shell with a diameter of 105 mm ranged from 80 to 100 μm. The average percentage of the inner layer was about 45%, the middle layer is about 10% and the outer layer is approximately 45%.
The structure of this shell corresponds to the above-described structure Z/B/A. the Outer layer (Z) is especially Serkova the first and makes the surface extremely light Shine. The surface properties of the sleeve shown in the table.
Example 2. The wollastonite and PA 6, duono-extruded and thermally stabilized sleeve.
Using co-extrusion technology with three single-screw extruders and extrusion connected ring tip was obtained three-layer primary sleeve
- inner layer consisting of 80 wt.% PA6 (®Grilon F34) and 20 wt.% PA/6T (®Grivory G21),
- middle layer, consisting of an adhesion promoter based on LLDPE grafted (MSA®Modic-AP L513), and
- outer layer consisting of the obtained double-shaft mixer compound of 89 wt.% polyamide PA 6 (®Grilon F34) and 11 wt.% of wollastonite (®Tremin 283 100 EST).
Primary sleeve was quickly cooled to about 20°C, then heated to about 80°C and at this temperature was pulled on two axes before drawing multiplicity surface 9,25. Then in the next zone heating the sleeve thermostabilizers, so that thermal shrinkage, measured in water at 80°C was approximately 10%to 12%. The diameter of thermally stabilized sleeve was 108 mm full thickness of 80 to 100 microns. While about 40% were in the inner layer, approximately 5% on the middle layer and approximately 55% for the outer layer. The last layer is the outermost layer (Z). It differs, among other things, a very low surface gloss (see table). The structure of this shell is suitable for the t of the above-described structure Z/HV/A.
Example 3. Quartz and PA 6, duono-extruded and thermally stabilized sleeve.
Devuono-extruded and thermally stabilized three-layer sleeve with a diameter of 108 mm and a total thickness of 80 to 100 microns was obtained as described in example 2. Unlike the previous examples located outside layer consists of the obtained double-shaft mixer compound of 92 wt.% polyamide PA 6 (®Grilon F34) and 8 wt.% quartz (®Silbond W6 EST). And located outside the layer (Z) is especially low surface gloss (see table). The structure of this shell corresponds to the above-described structure Z/HV/A.
Comparative example 1. Devuono-extruded and thermally stabilized sleeve.
Analogously to example 2 was obtained devuono-extruded and thermally stabilized three-layer sleeve, consisting of
- inner layer consisting of 85 wt.% PA6 (®Grilon F34) and 15 wt.% PA/6T (®Grivory G21),
- the middle layer, consisting of 50 wt.% polyethylene LDPE (®Escorene LD165BW), mixed with 50 wt.% LLDPE grafted MSA, as adhesion promoter (®Admer NF518E) and
- the outer layer, consisting of 83 wt.% PA6 (®Grilon F34), 10 wt.% PA/6T (®Grivory G21) and 7 wt.% brown dye.
Full wall thickness was 50 μm when the diameter of 80 mm, While the share of the inner layer was approximately 20%, the share of the middle layer to about 40% and the proportion of the outer layer of about 40%. Surface than the described membranes according to the invention was very smooth and shiny, as shown in the following table.
|The composition of the layer (Z) and the properties of its surface depending on the presence or absence of inorganic particles|
|Example||The outer layer Z||The distribution of particle size,|
|Roughness, µm||The measure gloss at 60°||Tactile impression||The visual impression|
|1||Cristobalite and PA||33||120||3,0||17,1||26,2||12,1||very good||very good|
|2||Wollast the bat and PA6||8||50||2,5||11,1||16,3||16,3||very good||very good|
|3||Quartz and PA6||40||120||3,2||14,0||22,5||11,8||very good||very good|
|Cf. Ave 1*||Without organic particles||-||-||0,3||3,0||3,5||90,0||very poor||very poor|
The table shows that the described membrane according to the invention for the food products prepared by the above method, due to the location outside the layer (Z), which contains inorganic particles, differ markedly from conventional membranes with respect to their surface properties.p> The size distribution of inorganic particles was determined by laser granulometry in dilute aqueous suspension. The degree of roughness was determined according to DIN 4762, ISO 4287/1 and DIN 4762/1E with parametrom S5P with the tester for measuring the profile RHT6/50E 6110457 (diamond) when the cut-off level of 0.8 mm, an Average roughness value Rais the arithmetic mean value of all deviations of the roughness profile from the mean line within the entire measurement area. The average height of the roughness profile Rzis the average of the individual heights of the irregularities on five successive selected portions of measurements in each 5 mm length in the profile roughness. The maximum height of the roughness Rmaxis the largest of the five specific individual values of roughness. The degree of roughness were averaged over 5 measurements.
Indicator gloss was determined according to DIN 67530, ISO 2813 and ASTM D 523 at an angle of incidence of 60° Micro-Gloss 60 by BYK Gardner. This register is reflected from the surface light photoelectric methods. The smaller the indicators Shine, the more matte look of the surface.
Shell according to the invention look, in particular, is very similar to collagen casings.
1. Sextravaganza thermoplastic shell for food, is broken off from, at least two layers including an outer layer (Z), and at least one layer which is an outer layer (Z), contains more than 50 wt.% thermoplastic components based on (co)polyamide(s), and the outer layer (Z) contains more than 50 wt.% thermoplastic components and distributed them in the inorganic particles, at least part of which has a diameter equivalent to a sphere more than 20 μm, and the surface of the outer layer (Z) has a roughness Rzaveraged over 5 measurements of at least 5.0 µm and the mass ratio of the inorganic particles and polymers in the outer layer is in the range of 0.1:to 99.9 to 50:50.
2. Casing for food products according to claim 1, characterized in that thermoplastic components in the outer layer (Z) based on (co)polyamide(s).
3. Casing for food products according to claim 1, characterized in that at least one of the layers except the outer layer (Z), performs carrier function.
4. Casing for food products according to claim 1, characterized in that the outer layer (Z) contains at least 0,05% vol. inorganic particles with a diameter equivalent to a sphere, at least 20 μm or displacement of particles, at least 4189 μm3.
5. Casing for food products according to claim 1, wherein the combination of inorganic particles of the outer layer (Z) or, at least, its particles are mostly isometric forms have the distribution of the diameter of the equivalent sphere, at least in the range from 20 to 40 microns.
6. Casing for food products according to claim 1, wherein the combination of inorganic particles of the outer layer (Z) contains at least 10 vol.% of the total volume of inorganic particles, mainly of particles isometric form, or/and at least up to 2% vol. of the total volume of inorganic particles, mainly of particles having a fibrous, needle and/or linear form.
7. Casing for food products according to claim 1, characterized in that the outer layer (Z) contains at least 0.5 wt.% inorganic particles, among which in the outer layer (Z) if necessary, is at least 0.1 wt.% inorganic fibers.
8. Casing for food products according to claim 1, characterized in that the inorganic particles mainly or almost entirely comprised of particles on the basis of aluminum oxide, carbonate, phosphate, silica, silicate, sulfate, minerals and/or vitreous substances.
9. Casing for food products according to claim 1, characterized in that the outer surface layer (Z) has a gloss measured at the Micro-Gloss 60 by BYK Gardner, averaged over 5 measurements, not more than 65.
10. Casing for food products according to claim 1, characterized in that it along with the outer layer (Z) has at least one layer selected in the layers (a) fraction of thermoplastic mA is eriala based on (co)polyamide(s), layers (C) fraction of the polyolefin(s) and layer (C) with barrier effect for oxygen and other gases, and optionally, at least one layer of HV as an intermediate layer of adhesion promoter and/or an inner layer of adhesion promoter.
11. Casing for food products according to claim 1, characterized in that it along with the outer layer (Z) has at least one layer (a) fraction of thermoplastic material based on (co)polyamide(s) and at least one layer of HV as an intermediate layer of adhesion promoter and/or the inner layer of adhesion promoter.
12. Casing for food products according to claim 1, characterized in that it biaxial stretched and has a residual shrinkage of from 5 to 20% in the longitudinal and transverse directions, measured after 20 min of incubation heated to 80°With water.
13. Casing for food products according to claim 1, characterized in that it is obtained by molding blow.
14. The use of membranes for food on one or more of claims 1 to 13 as an artificial sausage casings.
SUBSTANCE: film contains a primary layer (A) made from polyolefin foam, containing 0.5 to 25 wt % nucleating agent, layer (B) based on the same polyolefin as the primary layer, an optional adhesive layer (C), barrier layer (D) optionally impermeable for gases and/or smell, adhesive layer (E) and a thermosealing and/or laminated surface layer (F). Total thickness of layers (A) and (B) lies between 0.5 and 2 mm, and thickness of layer (B) ranges from 1/6 to 1/2 of thickness of layer (A). The said multilayer film is suitable for thermoshaping on shaping-packaging-thermo welding machines.
EFFECT: product has good mechanical properties.
17 cl, 1 ex, 2 tbl
FIELD: chemistry; packing.
SUBSTANCE: oxygen-absorptive packing material is intended for packing of food products. Material includes solid layer of base from paper, oxygen-absorbing composition, placed on at least one side of base layer and film layer from polypropylene film, placed on oxygen-absorbing layer. Oxygen-absorbing composition includes adhesive emulsion and suspended in it absorbent of oxygen, which contains electrolytically restored iron and salt as electrolyte. One of said base layers and said film layer can have printed letters for provision of information, relating to packed product.
EFFECT: prevention of decomposition, spoiling and oxidation of food products.
13 cl, 12 ex, 1 tbl, 6 dwg
FIELD: packing industry.
SUBSTANCE: invention relates to technology of obtaining packing materials, in particular to laminates for additives transferring, acceptable for packing food product, which is boiled in packing, additives from laminate passing from laminate into food product. Laminate contains substrate and layer for additive transferring. Layer for additive transferring consists of water-insoluble thermoplastic polymer, agent increasing polymer impact viscosity and additive granules which contain coloring substance, flavour additive and aromatiser. Agent increasing polymer impact viscosity is contained in mixture with water-insoluble thermoplastic polymer. In packing product laminate is connected to itself or to other element of packing product-packet, bag, lid, etc.
EFFECT: invention allows to improve appearance of food product after transferring food additive into food product, ensures more even distribution of food additive on or in food product.
28 cl, 10 dwg, 10 tbl, 69 ex
FIELD: food industry.
SUBSTANCE: invention is related to multilayered plastic sheet used for food packaging It has some areas provided with adhesive properties used for one-sided thermo connection on the outside of the film and two-sided thermo connection, in other words thermo connection on the outside and inside of the film.
EFFECT: film produced has excellent adhesive properties and prevents patching of layers while rolling.
10 cl, 1 dwg
SUBSTANCE: it is implemented aluminium reactionary evaporation and reactionary gas is fed into coating spraying machine on belt padding with receiving of coating from aluminium oxide. Before plating made of aluminium oxide on padding by magnetron sputtering it is applied short close layer of metal or metal oxide.
EFFECT: there are received transparent barrier coatings without high technological expenditures.
18 cl, 1 ex
FIELD: packing industry.
SUBSTANCE: invention relates to production of ecologically safe packages and refers to a cigarette pack comprising a closing and opening outer box and an inner packing placed inside the outer box. The inner packing encloses a set of rod-like smoking products and an inner wrapping which covers this set. The inner wrapping comprises the first paper layer forming one inner wrapping surface, the second paper layer forming the other inner wrapping surface and a moisture-proof layer between the first and the second paper layers. The moisture-proof layer contains solid paraffin as a basic component and its thickness is enough to provide for the first and second paper layers to be glued together. Wrapping paper as well as the method and machine for its production are proposed.
EFFECT: increased moisture resistance, flavour keeping and improved biological decomposition.
20 cl, 9 dwg
SUBSTANCE: coating film for children-protected and old-people-friendly blister packs has a hot shaped or cold shaped substrate (blister) and is designed for packing drugs and medical products. The coating film includes 5 to 30-mcm thick aluminum foil, which is either uncovered on one - first - side or covered with protective varnish applied with mass flowrate from 0.1 to 10 g/m2, or is lined with paper of a density from 17 to 60 g/m2 or 5 to 15-mcm polyester film. On the other - second- side destined for heat sealing with the blister pack substrate, the coating film is lined with uniaxially or biaxially stretched polymer film made of either 10 to 40-mcm polyvinyldichloride (PVDC) or 6 to 35-mcm polypropylene (PP) or 5 to 15-mcm polyester resin or 8 to 76-mcm polychlorotrifluoroethylene (PCTFE) or 10 to 40-mcm cycloolefine copolymer. The given coating film is used for blister packs.
EFFECT: elective protection of blister packs against children and convenient opening by old people by pressing.
19 cl, 1 tbl
FIELD: transportation; packing.
SUBSTANCE: composite sheet material includes sheet of transparent amorphous thermoplastic material with or without toning. Face side of material is intended for contact with food, rear side has adhesive solid or perforated decorative material layer made of thermoplastic paints. This layer may be monocolour or multicolour. Rear side layer of decorative material and also rear side of said sheet in places of orifices is covered by adhesive layer of aluminium.
EFFECT: enhancement of aesthetic appeal of packaged food with package made of thermoplastic material securing high ecological safety.
FIELD: technological processes, chemistry.
SUBSTANCE: polymer material is produced from mixture of complicated polyether resin and polyolefine. Package includes metal base coated with polymer material. Adhesive layer is installed between layer that contacts with product and the base. Volumetrical layer is located between adhesive layer and layer that contacts to the product.
EFFECT: characteristics of product release are improved.
19 cl, 5 tbl, 5 ex
FIELD: packages, particularly wrappers.
SUBSTANCE: wrapping material comprises laminate including at least one flat paper layer and at least one additional corrugated paper layer with wave amplitude defined in direction transversal to additional paper layer movement. The flat and corrugated paper layers are connected with each other by means of adhesive. Additional paper layer also includes substantially parallel wave system with amplitude defined in additional paper layer movement plane.
EFFECT: increased rigidity without material weight increase, improved voluminosity and wear resistance, enhanced printability.
5 cl, 2 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to production of electro-insulating materials with sophisticated shape, for example representing a hollow cylinder with end face annular ledge that can be used in electrical equipment as dielectric components. Proposed method comprises producing a pack of uniformly distributed polymer composite material layers from at least three half-finished glass cloth products representing a truncated sector, its upper part, along truncating line, mating rectangular element. Aforesaid half-finished products are placed in mould that mates the formed part profile with overlapped edges and shifted line of conjugation from layer to layer. Note here that rectangular elements of every prefinished product are distributed over inner walls of the mould cylindrical part, while its rounded edges are bent off onto the mould circular ledge. Each layer is impregnated with a mix of epoxy-dianic and polyamide resins with subsequent formation of impregnated composition using a form-shaping element.
EFFECT: ease of manufacture.
2 cl, 8 dwg, 1 tbl, 5 ex
FIELD: packaging industry.
SUBSTANCE: invention is related to technology of synthetic films preparation, in particular to at least three-layer jointly extruded films stretched in two directions and may be used in food industry for packaging of meat and sausage products. Seamless tubular shell consists of the following layers, when looking inside from outside, a) external layer A from main component-polyamide or mixture of several polyamides, b) if necessary, layer B, which has property to block oxygen access, c) if necessary, central layer C from the main component - polyamide or mixture of several polyamides, d) layer D, relative to neighboring layer C or B or A and neighboring layer E acting as adhesion intensifier, and e) internal layer E from the main component - polyamide or mixture of several polyamides, f) if necessary, other layers and additives, at that at least one layer one layer contains natural fibers with fiber length in the range from 5 to 35 mcm and/or from 35 to 350 mcm and/or mixture of natural fibers from fibers of different type and/or different length.
EFFECT: shells have appearance and touch properties similar to natural ones, proper consumer and mechanical properties.
17 cl, 1 tbl, 2 ex
FIELD: food industry.
SUBSTANCE: invention is related to the technology of hand hose synthetic film production, in particular single- or multi- layer polyamide- or copolyamide-based film for food products or the one with polyamide- or copolyamide-based inner layer. Polyamide is acyclic or aliphatic and partially fragrant. Casing has permeability for water steam less than 30 g/m2 day, swelling ratio at least 5% Superficial tension of the inner side is more than 28 dine/cm2. Casing is saturated with smoking fluid with no additional means for browning. Almost all the smoking fluid is sunk by the casing.
EFFECT: particularly suitable for synthetic sausage casing especially for sausages for boiling, cooked and fresh sausages.
9 cl, 2 ex
FIELD: technological processes.
SUBSTANCE: invention concerns composite structure, method of its obtainment, and application. Composite structure is a sandwich structure consisting of two outer structural layers L1 and L3 and one inner lightening layer L2, made of solid or semisolid polyamide foam. Structural layer is a plate or sheet made of thermoplastic or heatset polymer matrix reinforced by reinforcement fiber, or a metal or metal alloy plate or sheet. Method of obtaining composite structure involves conjunction of the following elements: structural layer L1, lightening layer L2 of polyamide foam or the said foam precursor, structural layer L3. Composite structure can be applied in car or airplane part manufacturing, or production of sports gear, such as ski, or in construction panel manufacturing.
EFFECT: obtaining hard and light reusable composite structure.
20 cl, 6 ex,1 dwg
FIELD: food industry.
SUBSTANCE: invention is related to food mono- or multilayer cover made from thermoplastic mixture which contains at least one aliphatic polyamide and/or copolyamide at least one or several synthetic water-soluble polymers and at least one organic and/or inorganic filler, which is carbohydrate, organic synthetical fiber or organic synthetical powder of the medium fiber length respectively of the medium grain size 5-3000 micrometer. Besides the cover is characterised by permeability for water vapor which is determined in accordance with DEN 53122, in non-extended, monoaxially or biaxially extended condition 50-1500 g/m2 per day. The cover for food is designed to be used as man-made sausage cover, especially for summer sausage.
EFFECT: natural design, pleasant to touch, waterproof without additional stitching an characterised by high permeability for smoke and water vapor.
16 cl, 4 tbl, 2 ex
SUBSTANCE: invention refers to production technique of barrier layered polymer films. Single- or laminate film consists of, at least, one gaseous oxygen proof barrier layer. Layer is basically laminated with mixed ethylene copolymer and vinyl alcohol and, at least, one multipolyamide. Film is applied for packaging of perishable, outgassing products, such as foodstuffs. Packing made of this film for perishable, outgassing products represents first of all a package for cheese making its aging. The film possesses is minimum possible permeability almost independent of moisture content in packed product and/or in environment, thus ratio of carbon dioxide permeability and oxygen permeability is not less 3:1.
EFFECT: production of polymer film possessing minimum possible permeability almost independent of moisture content in packed product and/or in environment.
22 cl, 3 tbl, 1 ex
FIELD: food industry.
SUBSTANCE: invention relates to technology of manufacturing food packaging materials, in particular plane or tubular shells of films. Shell of film has layered structure with at least five and preferably at least seven layers. One of layers is made from polyvinyl alcohol, which layer can be disposed between two polyamine layers. Other layers can be made from polyolefins and contain adhesion enhancers.
EFFECT: enhanced barrier properties of packaging materials, improved size stability, and tightness of layers.
FIELD: casings adapted to be filled with food product such as meat, in particular, coatings for ham and sausages.
SUBSTANCE: according to first version, casing is made in the form of sleeve manufactured from five-layered film material, with first layer making outer layer and fifth layer making inner layer. First and fifth layers are manufactured from polyamide 6 or mixture of polyamide 6, copolyamide 6/6 and amorphous polyamide, second layer is binder between first and third layers and is made from modified polyethylene serving as adhesive, third layer is made from polypropylene, forth layer serves as binder between third and fifth layers and is made from modified polyethylene . According to second version, casing is made in the form of sleeve from five-layer film material, first layer serving as outer layer and fifth layer serving as inner layer. First layer is made from polyamide 6 or mixture of polyamide 6, copolyamide 6/6 and amorphous polyamide, second layer serving as binder between first and third layers is made from modified polyethylene serving as adhesive, third and fifth layers made from high-pressure polyethylene, fourth layer serving as binder between third and fifth layers is made from modified polyethylene. In both versions, sectional thickness of casing is D=40-60 microns, thickness of first layer is d1=(0.5-0.6)D, thickness of second and forth layers is d2=d4=(0.04-0.06)D, thickness of third layer is d3=(0.2-0.3)D, and thickness of fifth layer is d5=(0.08-0.12)D. During utilization, edges of casing may be secured by means of squeezing members manufactured from plastic material, such as aluminum or alloy thereof. Edges of casing may be also secured by means of welded joint allowing hermetically sealed cavity for receiving of food product to be defined. Air is pumped out of said hermetically sealed cavity or hermetically sealed cavity is filled with inert gas medium.
EFFECT: improved protecting properties of casing used for packaging of food products.
10 cl, 5 dwg
FIELD: polymer materials.
SUBSTANCE: title polyamides possess also a good elongation capacity and a high thermo-mechanical strength. Object of invention is to obtain polyamides, which would be characterized by resistance to ageing under high working temperature conditions with their flexibility preserved. Disclosed composition contains (i) 60 to 99.5% (preferably 70-93%) of at least one copolyamide depicted by formula X/Y,Ar, wherein Y represents aliphatic diamine groups containing 8 to 20 carbon atoms; Ar represents groups of aromatic dicarboxylic acid; X either represents groups of aminoundecanoic acid H2N-(CH2)10-COOH, lactam-12 or corresponding acid or X represents unit Y.x, which is group resulting from condensation of diamine with aliphatic dicarboxylic acid (x) containing 8 to 20 carbon atoms, or X represents unit Y,I, which is group resulting from condensation of diamine with isophthalic acid; and (ii) 0.5 to 40% (preferably 7-30%) of at least one product selected from plasticizers, nano-fillers, polyolefins, cross-linked polyolefins, and additives. Preferably, X/Y,Ar represents: (1) 11/10,T resulting from condensation of aminoundecanoic acid, 1,10-decanediamine, and terephthalic acid, (2) 12/12,T resulting from condensation of lactam-12, 1,10-decanediamine, and terephthalic acid, (3) 10,10/10,T resulting from condensation of sebacic acid, 1,10-decanediamine, and terephthalic acid, or (4) 10,I/10,T resulting from condensation of isophthalic acid, 1,10-decanediamine, and terephthalic acid. Invention also provides apparatus, materials, and structures involving proposed composition.
EFFECT: improved performance characteristics of material.
27 cl, 4 tbl, 4 ex
FIELD: processes of making laminate drawn and sealed flat films for making sealed tubular films, possibly, for making envelopes and packages for food products.
SUBSTANCE: flat film includes two sealed surface layers formed at least of one copolyamide and at least of one amorphous polyamide and (or) at least of one homopolyamide and(or) at least of one modified polyolefin. Such film is highly impermeable to steam and oxygen.
EFFECT: enhanced strength of film sealed joint.
26 cl, 3 ex
FIELD: technological processes.
SUBSTANCE: invention is related to technology for production of ultra-light unfolding space structures, in particular to multi-layer walls of inflatable and hardened gossamer structures. Multi-layer wall comprises layer of composite material (1), which is hardened by polymerisation. On internal side it comprises layer (2), which is impermeable for gases. On external side there is at least one protective and anti-adhesion layer (3). External layer (3) is partially permeable for gases and is not permeable for liquid and viscous phases of the main material of mentioned composite material (1).
EFFECT: provides for removal of air captured between different layers of multi-layer wall at the stage of pressure collapse.
21 cl, 4 dwg