Method of producing highly dispersed jointly ground calcium carbonate material of types gcc and pcc, obtained products and use thereof

FIELD: chemistry.

SUBSTANCE: invention can be used in chemical industry. The method of producing jointly ground calcium carbonate material, which contains ground calcium carbonate (GCC) material and precipitated calcium carbonate (PCC) comprises the following steps: a) obtaining at least one calcium carbonate material, optionally, in form of an aqueous suspension; b) combined grinding of GCC and PCC, optionally, with at least another mineral material which is selected from talc, clay, Al2O3, TiO2 or mixtures thereof; c) optional sieving and/or concentration of the jointly ground calcium carbonate obtained at step (b); d) optional drying of the jointly ground calcium carbonate material obtained at step (b) or (c). The fraction of particles of the obtained material with size smaller than 1 mcm is greater than 80%, preferably greater than 85%, more preferably greater than 90% and even more preferably greater than 95%. BET specific surface area is less than 25 m2/g.

EFFECT: invention enables to increase lustre of enamel paper.

44 cl, 2 tbl, 5 ex

 

The object of the present invention is a method of obtaining calcium carbonate material consisting of crushed calcium carbonate (GCC) and precipitated calcium carbonate (PCC). This material is used in many fields, for example in the paper industry.

Also the subject of the present invention is a method of producing calcium carbonate containing GCC and PCC, in which the fraction of particles smaller than 1 μm is more than 80%, more preferably 85%, more preferably 90% and more preferably more than 95% and which has a specific surface according to BET less than 25 m2/year

In the case where the fraction of particles smaller than 1 μm is more than 95%, the value of specific surface area by BET is preferably less than 25 m2/year / In the case when the fraction of particles smaller than 1 μm is more than 90%, more than 85% and more than 80%, specific surface area by BET is preferably less than 20 m2/g, less than 18 m2/g and less than 15 m2/g respectively. Such materials provide excellent properties of coated paper, in particular from the point of view of glitter.

The object of the present invention is also a method of obtaining calcium carbonate material that contains GCC and PCC with the above particle size distribution characteristics in which GCC and PCC are crushed together, maybe at least it is one mineral material.

Another object of the present invention is crushed together, the calcium carbonate materials (i.e. aqueous suspension of mineral materials, containing together crushed GCC and PCC, and dry products containing together crushed GCC and PCC), obtained by this method.

Another object of the present invention is the use of these products in any region where mineral materials, and in particular in the manufacture of paper, paints and plastics.

In compositions for coating paper in the paper industry uses many minerals. For this purpose, traditionally used clay because of its low cost compared to other mineral pigments.

Calcium carbonate (caso3) used as a pigment for coating and filler, and, in particular, it is known that it improves some optical properties of the final product, such as gloss, opacity or brightness. Calcium carbonate can be of two types: crushed or natural calcium carbonate, referred to as GCC, and synthetic or precipitated calcium carbonate, referred to as RCC.

Ground calcium carbonate is calcium carbonate from natural sources, such as limestone, marble or chalk processed by crushing. Precipitated calcium carbonate is a synthetic m is a material predetermined, usually obtained by precipitation from the reaction of carbon dioxide with lime in the aquatic environment. This RCC may be rhombohedral, and/or scalenohedron, and/or aragonite. In accordance with the wishes of the experts in this field, the surface of this GCC or PCC can be further processed, for example, stearin.

For many years there was a need to provide professionals in the field of mineral suspensions containing GCC and PCC, and it is interesting to note that both of the material included in the composition for coating paper, to more precisely control the final properties of the coated paper. Publications on the use in the paper industry, both natural and precipitated calcium carbonate include, for example, the work "PCC or GCC, the factors determining the choice of calcium carbonate to alkaline conversion" (published after the Annual meeting of the pulp and paper, November 28, 1995) and "advantages of the GCC compared to the RCC as the primary filler for plain and coated paper without wood pulp" (Tappi Journal, 2000, 83(5), p. 76): these publications relate to the properties of mixtures PCC/GCC used in the paper industry. In the work "Mel: calcium carbonate for highly filled thin sheets" (TAPPI Proceedings, April 5-8 1992, the Papermakers Conference, Book 2, Opryland Hotel, Nashville TN, TAPPI Press, pp.515-520) the author believes that the shortcomings Rssmore be overcome by the use of this mineral with other fillers, such as GCC. Finally, in "the structure of the coating with pigments from calcium carbonate and its impact on gloss paper and printed products (Pulp & Paper Canada, 2004, 105(9), pp.43-46) studied the effect of mixtures of different pigments, comprising GCC and PCC, on the properties of paper, including glitter paper and the brightness of the print. The applicant emphasizes that these publications, apparently, form the technical background of the invention as evidenced by the need to obtain a mixture of GCC and PCC for use in the paper industry. However, no article is not considered joint grinding of GCC and PCC and further opportunities product of co-grinding with a given fraction of small particles, which is one of the objects of the present invention.

Due to the need to improve some of the final properties of the coated paper, the existing experts in this field, the experts there is also an additional need to improve some of the optical properties of the final products, such as gloss. In connection with this requirement, the specialist is known that the degree of grinding of mineral materials used in compositions for coating paper, is a very important criterion: the degree of grinding of mineral materials has a significant impact on the improvement of the optical properties of coated BU the AGI.

In this area specialists known patent EP 0894836, in which is disclosed a suspension consisting of water produced by the industry of dispersant, which prevents dissociation agglomerated pigment in suspension, and agglomerated pigment containing carbonate, with the distribution of particle sizes in which 80-99 wt.% particles have a size less than 2 microns, 50 to 90 wt.% less than 1 μm and 0-10 wt.% less than 0.2 μm, the coefficient of the slope (the ratio of the diameter at 50 wt.% and diameter at 20 wt.%) equal to 1.5-2.0 and porosity is 45-65%. It is obvious that this invention applies only to natural calcium carbonate type of calcite, marble, and chalk; moreover, the invention relates to a method of dispersing and does not consider grinding the above pigment containing carbonate. U.S. patent 2002155055 refers to the problem of reducing the width of the distribution of particle size in the compositions of calcium carbonate used for paper processing, but it is only powdered calcium carbonate, as shown by the authors. Proposed there is a method comprising a stage of formation of the aqueous suspension of natural calcium carbonate, not containing dispersant, wet milling the suspension with the formation of the composition of calcium carbonate with a coefficient of slope (A) and aging suspensive temperatures below 35°C with the formation of the composition of calcium carbonate with a coefficient slope (In), smaller than the ratio (A). In this document, the coefficient of the slope is defined as the average particle diameter of 75 wt.%, divided by the average particle diameter of 25 wt.%, moreover, the distribution of particle sizes determined by Sedigraph™.

Also known documents of the prior art relating to the use of calcium carbonate of one type or both types (a mixture of GCC and PCC) in combination with at least another mineral material (and in particular, kaolin) and revealing the specific values of the coefficient of the slope of each material and/or the final mixture. In WO 2003/093577 shown that to obtain the improved options paper - gloss, opacity, brightness and smoothness - in compositions for coating paper can be used particles of a specific pigment. These pigments contain the first component, which represents the RCC, and the second component - treated particles of the aqueous kaolin clay with a shape factor of at least 25 and a steepness factor of at least 20, or the first component RCC with spherical particles and a second component which is the crushed particles of the aqueous kaolin clay with a shape factor of at least 45 and an average equivalent diameter of particles less than 0.5 micron, or the first component of the RCC and the second component, which is crushed to particles of the aqueous kaolin clay with a coefficient of less than 25. Moreover, in WO 2002/016509 shown that to improve the optical properties of paper and the suitability of the coated paper for printing is better to use kaolin with an average particle size of 0.7 to 3 μm and a shape factor of at least 60; this type of kaolin can be used in combination with another filler such as talc, calcium sulfate and/or carbonate of alkaline earth metal. Finally, in WO 2000/066510 shown that to improve the optical properties and the suitability of the coated paper for printing, you can use a pigment composition containing a mixture of fine kaolin obtained from block kaolin clay and calcium carbonate, which can be either the GCC or PCC, in which particles of both types have an average size of less than 0.8 μm and a coefficient of steepness, defined as 100×d30/d70more than 38 and in which the weight ratio of kaolin/carbonate is 40/60, preferably 50/50. Despite the fact that the last three documents relate to the use of mixtures of calcium carbonate (probably as GCC and PCC and kaolin that is not a requirement of the present invention, they do not consider the possibility of getting together crushed PCC and GCC, and even the possibility of joint grinding of kaolin with calcium carbonate at least one type.

To the scope of the present invention are close is also the documents, concerning the use of mixtures of GCC and PCC, in particular for use in compositions for paper, improving some optical properties of coated paper.

In WO 2004/016566 disclosed a method of preparation of the pigment composition, which consists in mixing the RCC with an average particle diameter of less than 1.6 μm and GCC with an average particle diameter of 0.8 μm at a weight ratio of PCC and GCC from 3:2 to 1:9. The proposal says nothing about the final fraction of fine particles obtained by this method of the invention. However, the examples clearly show that the weight percent of particles smaller than 1 μm significantly below 50%.

In DE 4128570 disclosed carbonate filler and a pigment with a specific shape and size of particles for filling and coating of paper and giving it a high opacity, high degree of whiteness and high occupancy rates. Such carbonate filler and pigment contains particles rhombohedral or round shape with a gradient ratio (the ratio of the particle diameter in microns at 50/20 wt.%), equal to 1.1 to 1.4, the ratio R equal to % of the particles smaller than 1 μm/% of particles smaller than 0.6 μm, in the range of 8-19 and the statistical average particle diameter in the range of 0.4-1.5 μm. This document also shows that it is possible to obtain a mixture of particles of calcium carbonate, which are smaller than 1 μm by 70% and preferably 95% of the dry material.

Finally, in WO 2004/059079 escrita composition of particles of pigments, used for processing of paper containing the first pigment, which is a powdered calcium carbonate, and a second pigment, which is precipitated or ground calcium carbonate, and the first and second pigments are characterized by different distribution coefficients of the slope in size (100×d30/d70). More specifically, the claimed composition of the pigment particles contains two pigment component. The first contains particles of carbonate GCC coefficient slope of 30 to 45, and the second contains the RCC with the ratio of the slope of 55 to 75 and a maximum diameter of 0.5 μm or GCC with the ratio of the slope of 40-55. Conducted by the applicant tests n°10 and 13 disclose a mixture of calcium carbonate both types, in which 87% (based on dry material particles have an average diameter less than 1 micron.

However, it is obvious that this invention is based on a mixture of calcium carbonate both types of GCC and PCC specialists to deal with new problems. Do we need finely chopped RCC with a specific grain size distribution, with the specified granularity is achieved by grinding in a dry form and/or in aquatic environments. However, it was found that after this stage crushing the obtained fine particles RCC stick together and should be deagglomeration (how deagglomerate such melkorazdroblennyh RCC disclosed, in particular,in JP 2001089505, JP 56104713, US 6143065 or US 5279663) mechanically and/or by introducing dialamerica reagents: this stage requires additional costs for the RCC; it is necessary to carry out this stage of deagglomeration economically. Finally, in a joint grinding of GCC and PCC in contrast to the separate grinding of each component before mixing, in particular by using the following special beaded beads containing cerium oxide, was observed a striking increase the grinding efficiency (decrease in the total energy consumption for production of final products with the desired fraction of particles smaller than a given value).

As shown above, the experts in this field for cost-effective production of paper necessary suspension of minerals as GCC and PCC, in order to avoid, in particular, more expensive stages of deagglomeration RCC, which is necessary in the case of a simple mixture of GCC and PCC.

In the present invention was unexpectedly found a new method of production of a suspension of minerals as GCC and PCC, which is free from drawbacks of prior art.

This method consists in cooking together crushed calcium carbonates types GCC and PCC, containing the fraction of particles smaller than 1 μm in more than 80%, preferably more than 85%, preferred is timeline more than 90% and even more preferably 95%, with a specific surface area according to BET less than 25 m2/year

In the case when the fraction of particles smaller than 1 μm is more than 95%, the value of specific surface area by BET is preferably less than 25 m2/year / In the case when the fraction of particles smaller than 1 μm is more than 90%, more than 85% and more than 80%, specific surface area by BET preferably is respectively less than 20 m2/g, less than 18 m2/g and less than 15 m2/year

It should be noted for comparison that usually grinding of GCC with the formation of the fraction of particles smaller than 1 μm leads to a value of specific surface area by BET more than 25 m2/year

More specifically, the present invention provides a method of manufacturing together smallchange the calcium carbonate material that contains GCC and PCC, in which:

the fraction of particles smaller than 1 μm is more than 80%, more preferably 85%, more preferably 90% and even more preferably 95%, and

- specific surface according to BET of less than 25 m2/g

moreover, this method differs in that it involves the following stages:

a) obtaining at least one calcium carbonate material, not necessarily in the form of an aqueous suspension,

b) co-grinding of GCC and PCC, optionally, at least another mineral material

c) selecting, screening and/or concentration together crushed carbonate the calcium material, obtained in stage (b),

d) optionally, drying the crushed together, the calcium carbonate material obtained in stage (b) or (C).

This method allows the person skilled in the art to obtain the aqueous suspension and/or dry product, containing both GCC and PCC, which can specifically be used in the paper industry. Moreover, due to the presence of specific fractions of particles smaller than 1 µm and the specific choice of the value of specific surface area by BET achieving high gloss coated paper. Finally, it was unexpectedly found that the implementation stage of the joint grinding is no longer needed additional stage of deagglomeration RCC: as a result of the method according to this invention is less costly than methods of the prior art based on simple mixing GCC and PCC, which require first deagglomerate RCC. Thus, when the joint grinding of GCC and PCC in contrast to the separate grinding of each component before mixing, in particular when using the following special beaded beads containing cerium oxide, there is a striking increase in the efficiency of crushing (decrease in the total energy consumption to obtain the final product with the desired fraction of small particles).

The applicant would also like to mention EP 0850880, disclosed in which water is the first slurry or dewatered wet sludge with a concentration of solids 25-75%, containing a mixture of PCC and decreasing the viscosity of the reagent, which is dispersed in the mixer with the formation of a slurry with a viscosity below 1000 CPS (at 25°C)containing particles of calcium carbonate with an average diameter of 0.2 to 3 microns. The suspension is then mixed with dry particles of crushed calcium carbonate with an average diameter of 1.5 to 30 μm and the weight ratio of from 20:80 to 80:20 and the concentration of solids 60-85%. Then the suspension is dispersed in the mixer until a viscosity below 1000 SP and finally dispersed in the grinding device with the sand and get a water suspension containing particles of calcium carbonate with an average diameter of 0.2 to 2 μm. This patent also mentions that the obtained particles of calcium carbonate have a specific surface according to BET in the range of 5-25 m2/, Patent EP 0850880 interprets this method as a solution to problems associated with high shear viscosity that occur during grinding of the wet component of GCC, which represent a technical problem beyond the scope of the present invention. On the contrary, in the proposed by the applicant of the invention for the first time found that the wet grinding is also not result in the loss of Shine. Moreover, in the above-mentioned patent does not contain links to any gain in energy consumption for the product when implementing this method, which they dry grinding of GCC. NAC is the end, in this patent does not indicate that to increase the gloss of the paper energetically economical way to achieve the desired degree of comminution and the desired value of the specific surface according to BET.

The first object of the present invention is a method for the production of crushed together, the calcium carbonate material that contains GCC and PCC, in which:

the fraction of particles smaller than 1 μm is more than 80%, more preferably 85%, more preferably more than 90% and even more preferably 95%, and

- specific surface according to BET of less than 25 m2/g

moreover, this method differs in that it involves the following stages:

a) obtaining at least one calcium carbonate material, optionally in the form of aqueous suspensions

b) co-grinding of GCC and PCC, optionally, at least another mineral material

c) selecting, screening and/or concentration together powdered calcium carbonate material obtained in stage (b),

d) no choice, drying crushed together, the calcium carbonate material obtained in stage (b) or (C).

In the case when the fraction of particles smaller than 1 μm is more than 95%, the value of specific surface area by BET is preferably less than 25 m2/year / In the case when the fraction of particles smaller than 1 μm is more than 90%, more than 85% of the more than 80%, specific surface area by BET preferably is respectively less than 20 m2/g, less than 18 m2/g and less than 15 m2/year

The method according to this invention differs in that in stage (a), the calcium carbonate material comes in the form of an aqueous suspension and in this aqueous slurry solids comprise 20-80%, preferably 50-75%, and most preferably 50-70%. Specified aqueous suspension can be obtained by dispersing the calcium carbonate material in the form of a wet sludge.

According to this particular variant of the method according to this invention is also characterized in that the calcium carbonate material that comes in the form of aqueous suspensions is a GCC.

In this particular embodiment, the wet shredded natural calcium carbonate may undergo enrichment before stage (b), for example, using froth flotation, which will remove impurities types of silicates.

In another embodiment, the method according to this invention is also characterized in that the hold stage (s).

In another embodiment, the method according to the invention also differs in that the hold stage (d).

In a more General sense, the method according to the present invention is also characterized in that the co-grinding of GCC and PCC in stage (b) is carried out in aqueous medium in which the concentration of calcium carbonate is in the range is 20-80% (calculated on the dry weight of calcium carbonate), preferably 50-75%, and most preferably 50-70%.

The method according to this invention is also characterized in that at least one dispersant and/or contributing to the reduction reagent that is present in a weight % relative to the total dry mineral material in the range of 0-2%, preferably 0.2 to 1.4% and most preferably 0.5 to 1.2%, can be added before, during or after stage (b). Such additives can be entered to obtain a stable viscosity by Brookfield™ less than 3000 MPa·s, preferably less than 1000 MPa·s at 25°C.

The person skilled in the art will choose a dispersing and/or contributing to the reduction reagent depending on the properties that they need. You can use, for example, homopolymers of methacrylic acid and/or methacrylic acid in combination with other water-soluble monomers, such as Homo - and copolymers, which are fully or partially neutralized.

The method according to this invention is also characterized in that the co-grinding of GCC and PCC in stage (b) is carried out in the presence of at least one mineral material, which is chosen from talc, clay, Al2O3, TiO2or mixtures thereof.

More preferably, another mineral material was selected from talc, clay or mixtures thereof.

It is most preferable that the s mineral represented talc or clay.

The method according to this invention is also characterized by the fact that the co-grinding of GCC and PCC in stage (b) is carried out at a pH above 7.

In another embodiment, the method according to this invention is also characterized in that the co-grinding of GCC and PCC in stage (b) is carried out at a pH above 10.

In another embodiment, the method according to this invention is also characterized in that the co-grinding of GCC and PCC in stage (b) is carried out at a pH higher than 11.

To raise pH, use one or more of the following ways: the addition of base, preferably one - or divalent cation, most preferably sodium or calcium, the addition of the alkaline form of the biocide or the formation of a hydroxide such as CA(Oh)2when the grinding material, for example, during co-grinding of PCC and GCC. The applicant indicates that he knows French patent 0500779, not yet published at the filing date of the present patent application, in which are mentioned biocides that can be added at the grinding stage (b).

The method according to this invention is also characterized in that the contents of the grinding device is heated to a temperature above 60°C, preferably above 90°C. and most preferably above 100°C.

Temperature refers to the temperature of the contents grinding device at any point in the grinding device is istwa. In particular, the contents of the grinding device at the bottom may have a higher temperature due to increased hydrostatic pressure.

The method according to this invention is also characterized in that the RCA at the stage of joint grinding (b) is 10-90% of the total weight of PCC and GCC, preferably 20-80% of the total weight of PCC and GCC, and most preferably 30-70% of the total weight of PCC and GCC.

The method according to this invention is also characterized in that the co-grinding of GCC and PCC in stage (b) is conducted in the presence of grinding balls of zirconium oxide containing cerium oxide as a grinding medium, with the following characteristics:

- the content of cerium oxide is approximately 14-20 wt.% the total weight of the specified ball, preferably about 15-18 wt.% the total weight of the specified ball and most preferably about 16 wt.% the total weight of the specified ball; and

- the average grain size after annealing the grains forming the balls is less than 1 μm, preferably less than 0.5 microns and most preferably less than 0.3 microns.

The grain size is determined by analysis of the micrographs obtained by scanning electron microscope. The content of cerium oxide in the beads analyzed by optical emission spectrometry ICP.

The method according to the invention also differs in that the ball shall have an initial diameter to grind about 0.2 to 1.5 mm, preferably about 0.4 to 1.0 mm

Another object of the present invention is crushed together, the calcium carbonate material containing GCC and PCC, characterized in that it is obtained by the method of this invention.

Another object of the present invention is calcium carbonate, the material comprising GCC and PCC, characterized in that it is in the form of an aqueous suspension, in which:

the fraction of particles smaller than 1 μm is more than 80%, more preferably 85%, more preferably 90% and even more preferably 95%, and

- specific surface according to BET of less than 25 m2/year

In the case when the fraction of particles smaller than 1 μm is more than 95%, the value of specific surface area by BET is preferably less than 25 m2/GV case when the fraction of particles smaller than 1 μm is more than 90%, more than 85% and more than 80%, specific surface area by BET is preferably less than 20 m2/g, less than 18 m2/g and less than 15 m2/g, respectively.

According to the above option together powdered calcium carbonate material in the form of an aqueous suspension is also different in that it contains 20-80% of dry calcium carbonate, preferably 40-75% of dry calcium carbonate, and most preferably 60-70% of dry calcium carbonate.

Together crushed carbonate to llevy material in the form of an aqueous suspension also differs what weight fraction of RCC relative to the total weight of GCC and PCC is 10-90%, preferably 20-80%, and most preferably 30-70%.

Together powdered calcium carbonate material according to the invention containing GCC and PCC in the form of aqueous suspensions, also differs in that it has a steepness factor of at least about 30, preferably at least about 40, and most preferably at least about 45.

The coefficient of the slope is defined as d30/d70×100, where dxis an equivalent spherical diameter relative to which x wt.% particles are smaller.

Together powdered calcium carbonate material according to the invention containing GCC and PCC in the form of an aqueous suspension, is also distinguished by the fact that d50is approximately 0.2 to 2.0 μm, preferably 0.2 to 0.8 μm, and most preferably 0.25 to 0.45 μm. This d50determine using the Sedigraph™ 5100.

Together powdered calcium carbonate material according to the invention containing GCC and PCC in the form of aqueous suspensions, also differs in that the aqueous suspension contains at least one dispersant and/or contributing to the reduction reagent that is present in a weight % relative to the total dry mineral material in the range of 0-2%, preferably 0.2 to 1.4% and most predpochtitelno 0.5 to 1.2.

Together powdered calcium carbonate material according to the invention containing GCC and PCC in the form of aqueous suspensions, also differs in that the water suspension passed through a sieve of 40 μm, contains less than 1000 ppm ZrO2and less than 200 ppm SEO2.

Together crushed carbonate-Kaldewei material according to the invention containing GCC and PCC in the form of an aqueous suspension, is also characterized in that the aqueous suspension the weight ratio ZrO2/CeO2equals 4-6,5, preferably 4.6 to 5.7 and most preferably at 5.3. The content of ZrO2and CEO2determined by ICP-OES.

Another object of the present invention is crushed together, the calcium carbonate material containing GCC and PCC, which is characterized in that the dry product:

the fraction of particles smaller than 1 μm is more than 80%, more preferably 85%, more preferably more than 90% and even more preferably more than 95% and

- specific surface according to BET of less than 25 m2/year

In the case when the fraction of particles smaller than 1 μm is more than 95%, the value of specific surface area by BET is preferably less than 25 m2/year / In the case when the fraction of particles smaller than 1 μm is more than 90%, more than 85% and more than 80%, specific surface area by BET is preferably less than 20 m2/g, less than 18 m2/g and less than 15 m2/g, respectively.

Together powdered calcium carbonate material according to the invention containing GCC and PCC in the form of a dry product, also differs in that the weight fraction of RCC relative to the total weight of GCC and PCC is 10-90%, preferably 20-80%, and most preferably 30-70%.

Together powdered calcium carbonate material according to the invention containing GCC and PCC in the form of a dry product, also differs in that its coefficient of slope is at least about 30, preferably at least about 40, and most preferably at least about 45.

Together powdered calcium carbonate material according to the invention containing GCC and PCC in the form of a dry product, is also distinguished by the fact that d50is approximately 0.2 to 2.0 μm, preferably 0.2 to 0.8 μm, and most preferably 0.25 to 0.45 μm.

Together powdered calcium carbonate material according to the invention containing GCC and PCC in the form of a dry product, also differs in that the weight ratio ZrO2/SEO2it is 4-6,5, preferably 4.6 to 5.7 and most preferably 5,3.

Finally, another object of the present invention is the use of crushed together, the calcium carbonate material in this invented the Yu in any area, dealing with mineral materials, and in particular in industry, manufacturing of paper, paint and plastics.

EXAMPLES

The following examples are intended to illustrate some variants of the invention and do not limit its scope.

The average diameter was determined using a Sedigraph 5100™.

Example 1 - comparative example

Powdered calcium carbonate with an average particle diameter of 1.5 μm was subjected to wet grinding with a solids content of 74.5% in the presence of the following additives: 1,51% of sodium polyacrylate, a two-step method using a grinding bead balls of zirconium oxide containing cerium oxide, with an average diameter of the balls of 0.45 μm at a content SEO216 wt.% relative to the total weight of the ball and the grain size after sintering of 0.4 μm. Specific energy consumption for grinding of the material needed to obtain the final GCC fraction of particles smaller than 1 μm up to 97% in this material amounted to 270 kWh/so

The resulting suspension crushed GCC, then diluted to solids content 75%, added to the standard composition for coating paper, prepared with the following proportions of components:

100 parts of crushed GCC

10.5 parts of SBR latex

0.5 parts of a synthetic filler

0.2 parts of polyvinyl alcohol

0.2 parts of Svetlaya additive

In the specified coverage the final solids content was brought up to 68% and put on a standard pre-coated base paper not containing mechanical pulp, in the amount of 71 g/m2when the coating weight of 10 g/m2/side. This coated base paper was then Kalandarishvili using supercalender under the following conditions calendering: the speed of the calender 800 m/min, the load on the calender 200 kN/cm and a temperature of 105°C.

The surface gloss of coated paper was 70% Tappi 75°.

Example 2 is an illustration of the method according to the invention

A suspension of crushed calcium carbonate content of 76% solids and an average particle diameter of GCC 1.4 µm were crushed in the presence of a suspension of PCC with 51% solids and an average particle diameter of the RCC to 0.75 μm. The weight ratio of PCC and GCC in the grinding device was 50:50. The total content of solids in suspension in the chopping device was 61%, and the average diameter was equal to 1.1. The contents of the grinding device then crushed in the presence of the following additives: 0.95 wt.% polyacrylate sodium, using grinding bead balls of zirconium oxide containing cerium oxide, with an average bead diameter of balls 0.45 mm, content SEO216 wt.% relative to the total weight of the ball and a grain size after sintering, equal to 0.4 is km. The specific energy consumption for grinding required to obtain the final product of co-grinding with the fraction of particles smaller than 1 μm up to 97% in this material amounted to 200 kW·h/so

The resulting suspension jointly processed materials with solids content of 70.2% and then added to the standard composition for coating paper prepared from the following components in the following weight proportions:

100 parts jointly processed material

10.5 parts of SBR latex

0.5 parts of a synthetic filler

0.2 parts of polyvinyl alcohol

0.2 parts of brightening additive

In the specified coverage the final solids content was brought up to 68% and put on a standard pre-coated base paper not containing mechanical pulp, in the amount of 71 g/m2when the coating weight of 10 g/m2/side. This coated base paper was then Kalandarishvili using supercalender under the following conditions calendering: the speed of the calender 800 m/min, the load on the calender 200 kN/cm and a temperature of 105°C.

The surface gloss of coated paper was 72% Tappi 75°.

The results obtained are summarized in table 1.

Table 1
Example Example 2
The fraction of particles smaller than 1 μm in the final product grinding97%97%
The specific surface according to BET of the final product grinding28 g/m223 g/m2
The ratio of the steepness of the final product grinding3542
The average diameter of the end mill productof 0.27 μmof 0.27 μm
Full the specific energy of grinding required to get the product270 kW·h/t200 kW·h/t
Shine on Tappi paper, coated composition containing product70%72%
The brightness of the paper coated with the composition containing the product95,1%96,5%
The opacity of the paper coated with the composition containing the product89,7%90,2%

Table 1 is provided, the method according to this invention requires a smaller specific energy consumption for grinding to obtain a desired fraction of particles smaller than a given value, which leads to the same or an increased luster paper in comparison with the method of the prior art.

Example 3 is a comparative example

This example illustrates the mixture of PCC and GCC, in which each component is first separately crushed before mixing.

Aqueous suspension of PCC initial material containing 48% solids, with parameters given in example 3 of table 2, is subjected to wet grinding in a grinding device, using beaded balls of yttrium-stabilized zirconium silicate with a diameter of bead balls before chopping 0,6-1,0 mm Full unit cost of crushing required to obtain the final RCC material with the characteristics shown in table 2, was 50 kW·h/T. the Final solids content in this consistently concentrated suspension of PCC was 68%.

Aqueous suspension of GCC initial material containing 74% solids, with parameters given in example 3 of table 2, is subjected to wet grinding in a grinding device, using beaded balls of yttrium-stabilized zirconium silicate with a diameter of bead balls before ISM is liczeniem 0,6-1,0 mm Full unit cost of crushing required to obtain the final GCC material, with the characteristics shown in table 2, amounted to 210 kW·h/T. the Final solids content in the suspension GCC amounted to 75%.

PCC and GCC suspension is then mixed to obtain PCC/GCC mixture of material with a weight ratio of PCC:GCC as 30:70. This slurry is then added to the standard composition for coating paper prepared from the following components in the following mass proportions:

100 parts of GCC/PCC mixture of material

10.5 parts of SBR latex

0.5 parts of a synthetic filler

0.2 parts of polyvinyl alcohol

0.2 parts of lightening Supplement.

In the specified coverage the final solids content was brought up to 68% and put on a standard pre-coated paper not containing mechanical pulp, in the amount of 71 g/m2when the coating weight of 10 g/m2/side. This coated base paper was then Kalandarishvili using supercalender under the following conditions calendering: the speed of the calender 800 m/min, the load on the calender 200 kN/cm and a temperature of 105°C.

Optical properties of coated paper are shown in table 2.

Example 4 is an example according to this invention

This example illustrates together crushed PCC and GCC, obtained by the method according to this invention.

p> The suspension of ground calcium carbonate with a solids content of 74% and with the parameters given in example 4 of table 2, were subjected to wet grinding in a grinding device in the presence of a suspension of PCC with a solids content of 48% and with the options specified in example 4 in table 2. The weight ratio of PCC and GCC in the grinding device was 30:70, the solids content was equal 65,9%. The contents of the grinding device were crushed using a bead balls of yttrium-stabilized zirconium silicate with a diameter of bead balls before chopping 0,6-1,0 mm Full the specific energy consumption for grinding required to obtain the final product of co-grinding of GCC/PCC with the parameters given in table 2, amounted to 116 kW·h/T. the Final solids content in the suspension GCC was 70.3%.

This slurry is then added to the standard composition for coating paper prepared from the following components in the following weight proportions:

100 parts together crushed GCC/PCC

10.5 parts of SBR latex

0.5 parts of a synthetic filler

0.2 parts of polyvinyl alcohol

0.2 parts of brightening additive

In the specified coverage the final solids content was brought up to 68% and put on a standard pre-coated paper, desterrado wood pulp, in the amount of 71 g/m2when the coating weight of 10 g/m2/side. This coated base paper was then Kalandarishvili using supercalender under the following conditions calendering: the speed of the calender 800 m/min, the load on the calender 200 kN/cm and a temperature of 105°C.

Optical properties of coated paper are shown in table 2.

Table 2
ProductExample 3: a mixture of PCC/GCCExample 4: in conjunction crushed PCC/GCC
The parameters of the source material
GCCd50(µm)1,41,4
The coefficient. steepness2828
RCCd50(µm)0,750,75
The coefficient. steepness5555
The parameters of the final material
GCCd50 (µm)0,40-
The coefficient. steepness34-
RCCd50(µm)0,38-
The coefficient. steepness40-
PCC/GCCPCC/GCC masses.30/7030/70
d50 (ΜM)0,380,40
The coefficient. steepness3738
The fraction of particles with diameter less than 2 microns (%)to 89.5and 88.8
UD. surface18,118,2
Full the specific energy consumption162 kW·h/t116 kW·h/t
The options paper, coated end product1
Glitter paper (Tappi 75°)70,5%72%
Opacity90,4%90,5%
Brightness R45797,9%97,9%

Table 2 shows that the method of getting together the crushed material PCC/GCC according to this invention requires less energy consumption for grinding compared with the same mixture of PCC and GCC without loss of optical properties and even with improved optical properties.

Example 5

This example illustrates the application of the method according to this invention, which together crushed 3 mineral material, such as natural calcium carbonate, precipitated calcium carbonate and clay, using beaded beads of zirconium oxide containing cerium oxide in the amount of 16 wt.% relative to the total weight of the specified bulb, with an average grain size after sintering of the grains forming these balls is equal to 0.4 μm, and the average diameter of the balls of 0.45 mm Together the crushed material is then added to the composition for coating base paper and determine the resulting Shine.

Together crushed the following material is:

a suspension of crushed calcium carbonate containing 74% solids with an average particle diameter of GCC 1.4 µm and obtained with the use of 0.27 wt.% (calculated on the dry weight of GCC) homopolymer acrylic acid,

- suspension RCC containing 51% solids with an average particle diameter of RCC 0.8 μm and obtained with 0.7 wt.% (calculated on the weight of dry RCC) homopolymer acrylic acid,

and the clay suspension containing 68% solids, manufactured by HUBER™ branded Lithoprint™.

The weight ratio RCC:GCC:clay grinding device was 45:45:10.

The total content of solids in suspension in the chopping device was 72% and the average particle diameter of 2 tests, illustrating the invention, were 0.4 and 0.5 microns.

Then the contents of the grinding device together crushed in the presence of the following additives:

respectively 0.4 and 0.2 wt.% (based on dry weight of minerals) homopolymer acrylic acid, in which 14 mol.% carboxyl functional groups have been neutralized with sodium hydroxide, with a molecular weight of 5600 g/mol and a polydispersity of 2.4,

- grinding bead balls of zirconium oxide containing cerium oxide, with an average diameter of the balls of 0.45 mm and a content SEO216 wt.% respect to the total mass of the balls and the average size of the Eren after sintering, equal to 0.45 μm,

and together the crushed material contains particles with an average diameter of 0.4 and 0.5 μm, respectively.

Received 2 suspension together the crushed material is then added to the standard composition for a coating prepared from the following components in the following proportions:

100 parts together the shredded material

11 parts SBR latex (DL 966 from DOW CHEMICALS™)

0.5 parts of a synthetic filler (CMC FF5 from FINNFIX™)

0.4 parts of polyvinyl alcohol (PVA 4-98 from CLARIANT™)

0,6 part brightening additive (Blancophor™ P from BAYER™)

The composition was applied to a standard coated base paper number 78 g/m2when the coating weight of 10 g/m2/side. This coated base paper was then Kalandarishvili using supercalender the following conditions calendering: the speed of the calender 300 m/min, the load on the calender 170 kN/cm and a temperature of 80°C.

For together the crushed material with an average particle size of 0.4 μm, the surface gloss of coated paper was 73% Tappi 75°, and 45% DIN 75°.

For comparison the same floor, made of 100 parts of GCC with an average particle diameter of 0.4 μm, gave the luster 70% Tappi 75° and 35% DIN 75°.

For simultaneously crushed substance with an average particle size of 0.5 μm, the surface gloss of coated paper was 68% TAPPI 75° and 40% DI 75°.

For comparison, the same coating prepared from 100 parts of GCC with an average particle diameter of 0.4 μm, gave the luster 63% Tappi 75° and 33% DIN 75°.

1. Method for the production of crushed together, the calcium carbonate material containing ground calcium carbonate (GCC) and precipitated calcium carbonate (PCC), in which:
the fraction of particles smaller than 1 μm is more than 80%, more preferably 85%, more preferably more than 90% and even more preferably more than 95%, and
the specific surface according to BET of less than 25 m2/g
wherein the stage includes:
a) obtaining at least one calcium carbonate material, optionally in the form of aqueous suspensions
b) co-grinding of GCC and PCC, optionally, at least another mineral material which is chosen from talc, clay, Al2O3, TiO2or their mixtures
c) selecting, screening and/or concentration together powdered calcium carbonate, obtained in stage (b),
d) optionally, drying the crushed together, the calcium carbonate material obtained in stage (b) or (C).

2. The method according to claim 1, characterized in that in the case where the fraction of particles smaller than 1 μm is more than 95%, the value of specific surface area by BET of less than 25 m2/year

3. The method according to claim 1, characterized in that when the coat is Oia particles smaller than 1 μm is more than 90%, the value of specific surface area by BET is less than 20 m2/year

4. The method according to claim 1, characterized in that in the case where the fraction of particles smaller than 1 μm is more than 85%, the value of specific surface area by BET is less than 18 m2/year

5. The method according to claim 1, characterized in that in the case where the fraction of particles smaller than 1 μm is more than 80%, the value of specific surface area by BET is less than 15 m2/year

6. The method according to any one of claims 1 to 5, characterized in that in stage (a), the calcium carbonate material comes in the form of an aqueous suspension, and in this aqueous slurry solids comprise 20-80%, preferably 50-75%, and most preferably 50-70%.

7. The method according to any one of claims 1 to 5, characterized in that the calcium carbonate material is provided in the form of an aqueous suspension of stage (a)is a GCC.

8. The method according to any one of claims 1 to 5, characterized in that the hold stage (s).

9. The method according to any one of claims 1 to 5, characterized in that the conducting stage (d).

10. The method according to any one of claims 1 to 5, characterized in that the co-grinding of GCC and PCC in stage (b) is carried out in aqueous medium, and the concentration of calcium carbonate is 20-80% by dry weight of calcium carbonate, preferably 50-75%, and most preferably 50-70%.

11. The method according to any one of claims 1 to 5, characterized in that at least one disperging the rd and/or contributing to the reduction reagent, present in wt.% relative to the total dry mineral material in the amount of 0-2%, preferably 0.2 to 1.4% and most preferably 0.5 to 1.2%, is added before, during or after stage (b).

12. The method according to claim 11, characterized in that the co-grinding of GCC and PCC in stage (b) is carried out in the presence of at least one mineral material, which is chosen from talc, clay or mixtures thereof.

13. The method according to item 12, characterized in that the co-grinding of GCC and PCC in stage (b) is conducted in the presence of talc.

14. The method according to item 12, characterized in that the co-grinding of GCC and PCC in stage (b) is conducted in the presence of clay.

15. The method according to any one of claims 1 to 5, characterized in that the co-grinding of GCC and PCC in stage (b) is carried out at a pH above 7.

16. The method according to item 15, characterized in that the co-grinding of GCC and PCC in stage (b) is carried out at a pH above 10.

17. The method according to item 16, characterized in that the co-grinding of GCC and PCC in stage (b) is carried out at a pH higher than 11.

18. The method according to any one of claims 1 to 5, characterized in that during co-grinding of GCC and PCC in stage (b) the temperature of the comminuted material raised above 60°C, preferably above 90°C. and most preferably above 100°C.

19. The method according to any one of claims 1 to 5, characterized in that the weight fraction of RCC relative to the total weight of GCC and PCC sostav the em 10-90%, preferably 20-80%, and most preferably 30-70%.

20. The method according to any one of claims 1 to 5, characterized in that the co-grinding of GCC and PCC in stage (b) is conducted in the presence of grinding balls of zirconium oxide containing cerium oxide as a grinding medium, and the balls have:
the content of cerium oxide is between 14 and 20 wt.% the total weight of the specified ball, preferably between 15 and 18 wt.% the total weight of the specified ball and most preferably about 16 wt.% the total weight of the specified ball; and
the average grain size after annealing the grains forming the balls is less than 1 μm, preferably less than 0.5 microns and most preferably less than 0.3 microns.

21. The method according to claim 20, characterized in that the balls before chopping to have an original diameter of about 0.2 to 1.5 mm, preferably about 0.4 to 1.0 mm

22. Together powdered calcium carbonate material containing GCC and PCC, characterized in that it is obtained by the method according to any one of claims 1 to 21.

23. Together powdered calcium carbonate material containing GCC and PCC, characterized in that the aqueous suspension contains:
the fraction of particles smaller than 1 μm in more than 80%, more preferably 85%, more preferably more than 90% and even more preferably more than 95% and
has a value of specific surface area by BET less than 25 m /year

24. Together powdered calcium carbonate material according to item 23, wherein in the case where the fraction of particles smaller than 1 μm is more than 95%, the value of specific surface area by BET of less than 25 m2/year

25. Together powdered calcium carbonate according to item 23, wherein in the case where the fraction of particles smaller than 1 μm is more than 90%, the value of specific surface area by BET is less than 20 m2/year

26. Together powdered calcium carbonate according to item 23, wherein in the case where the fraction of particles smaller than 1 μm is more than 85%, the value of specific surface area by BET is less than 18 m2/year

27. Together powdered calcium carbonate according to item 23, wherein in the case where the fraction of particles smaller than 1 μm is more than 80%, the value of specific surface area by BET is less than 15 m2/year

28. Together powdered calcium carbonate material according to any one of p-27, characterized in that it contains 20-80% of dry calcium carbonate material, preferably 40-75% of dry calcium carbonate material and most preferably 60-70% of dry calcium carbonate material.

29. Together powdered calcium carbonate material according to any one of p-27, characterized in that the weight fraction of RCC relative to the total weight of GCC and PCC is 0-90%, preferably 20-80%, and most preferably 30-70%.

30. Together powdered calcium carbonate material according to any one of p-27, characterized in that it is the ratio of the slope is at least about 30, preferably at least about 40, and most preferably at least about 45, and the coefficient of the slope is defined as d30/d70·100, where d30and d70represent equivalent spherical diameters, for which 30 wt.% and 70 wt.% particles are of smaller size.

31. Together powdered calcium carbonate material according to any one of p-27, characterized in that the d50is approximately 0.2 to 2.0 μm, preferably about 0.2 to 0.8 μm, and most preferably about 0.25 to 0.45 μm, and d50is an equivalent spherical diameter for which 50 wt.% particles are of smaller size.

32. Together powdered calcium carbonate material according to any one of p-27, characterized in that the aqueous suspension contains at least one dispersant and/or contributing to the reduction reagent that is present in wt.% relative to the total dry mineral material in the range of 0-2%, preferably 0.2 to 1.4% and most preferably 0.5 to 1.2%.

33. Together powdered calcium carbonate materialon any of PP-27, characterized in that the aqueous suspension is passed through a sieve of 40 μm, contains less than 1000 million-1share ZrO2and less than 200 million-1share SEO2.

34. Together powdered calcium carbonate material according to any one of p-27, characterized in that the water suspension the weight ratio ZrO2/CeO2equals 4-6,5, preferably 4.6 to 5.7 and most preferably 5,3.

35. Together powdered calcium carbonate material containing GCC and PCC, characterized in that the dry contains:
the fraction of particles smaller than 1 μm in more than 80%, more preferably 85%, more preferably more than 90% and even more preferably more than 95% and has a value of specific surface area by BET less than 25 m2/year

36. Together powdered calcium carbonate material according p, characterized in that in the case where the fraction of particles smaller than 1 μm is more than 95%, the value of specific surface area by BET of less than 25 m2/year

37. Together powdered calcium carbonate material according p, characterized in that in the case where the fraction of particles smaller than 1 μm is more than 90%, the value of specific surface area by BET is less than 20 m2/year

38. Together powdered calcium carbonate material according p, characterized in that in the case where the fraction of particles smaller than 1 μm is more than 85, the value of specific surface area by BET is less than 18 m2/year

39. Together powdered calcium carbonate material according p, characterized in that in the case where the fraction of particles smaller than 1 μm is more than 80%, the value of specific surface area by BET is less than 15 m2/year

40. Together powdered calcium carbonate material according to any one of p-39, characterized in that the weight fraction of RCC relative to the total weight of GCC and PCC is 10-90%, preferably 20-80%, and most preferably 30-70%.

41. Together powdered calcium carbonate material according to any one of p-39, characterized in that the ratio of the slope is at least about 30, preferably at least about 40, and most preferably at least about 45, and the coefficient of the slope is defined as d30/d70·100, where d30and d70represent equivalent spherical diameters, for which 30 wt.% and 70 wt.% particles are of smaller size.

42. Together powdered calcium carbonate material according to any one of p-39, characterized in that the d50is approximately 0.2 to 2.0 μm, preferably 0.2 to 0.8 μm, and most preferably 0.25 to 0.45 μm, and d50is an equivalent spherical diameter for which 50 wt.% particles keytone size.

43. Together powdered calcium carbonate material according to any one of p-39, characterized in that the weight ratio ZrO2/CeO2it is 4-6,5, preferably 4.6 to 5.7 and most preferably 5,3.

44. The use of crushed together, the calcium carbonate material that contains GCC and PCC according to any one of p-43 in the paper, in particular, coated paper, paints and plastics.



 

Same patents:

FIELD: chemistry.

SUBSTANCE: suspension containing calcium carbonate is obtained by adding one or more zirconium compounds and possibly one or more other additives which do not contain phosphate, acting as a dispersant and/or an additive which assists in grinding. Calcium carbonate in dry form and/or in form of an aqueous dispersion or filtered residue is added an aqueous suspension and/or aqueous emulsion and/or aqueous solution containing one or more zirconium compounds. The zirconium compounds used is ammonium zirconium carbonate or calcium zirconium carbonate or mixture thereof.

EFFECT: invention enables to avoid the use of phosphate dispersants when preparing stable aqueous suspensions of calcium carbonate and increases content of solid substance in the suspension.

17 cl, 22 ex

FIELD: printing industry.

SUBSTANCE: to produce a precipitated calcium carbonate, a suspension of calcium hydroxide is made by mixing of quicklime with water in a reactor with a mixer or in a tank, then the produced suspension is filtered via a 100-mcm filter. The filtered suspension is sent into a reactor of stainless steel equipped with a mixer. Temperature from 10 to 70°C is set, afterwards the suspension is sent into a reactor or a tank for carbonisation, where a carbon-containing gas is bubbled through the suspension. The suspension is drained from the tank, when electric conductivity achieves the minimum level, and pH falls below 8. Coarse particles are removed at a 45-mcm filter. At the same time the carbonisation stage is carried out at speed of carbonising gas flow of below 30 litres per minute under normal conditions per kg of calcium hydroxide in process of deposition. Concentration of precipitated calcium carbonate is increased using a cationic, anionic or combined disperser under quite moderate or mild conditions, which do not cause considerable damage of aggregates/agglomerates, until concentration from 25 to 60% is achieved, preferably in the range from 35 to 50%, most preferably - from 39 to 40 wt % of hard substances.

EFFECT: invention makes it possible to produce porous stable agglomerates of precipitated calcium carbonate with size of 1-5 mcm.

22 cl, 5 dwg, 17 tbl, 9 ex

FIELD: printing industry.

SUBSTANCE: to produce a precipitated calcium carbonate, a suspension of calcium hydroxide is made by mixing of quicklime with water in a reactor with a mixer or in a tank, then the produced suspension is filtered via a 100-mcm filter. The filtered suspension is sent into a reactor of stainless steel equipped with a mixer. Temperature from 10 to 70°C is set, afterwards the suspension is sent into a reactor or a tank for carbonisation, where a carbon-containing gas is bubbled through the suspension. The suspension is drained from the tank, when electric conductivity achieves the minimum level, and pH falls below 8. Coarse particles are removed at a 45-mcm filter. At the same time the carbonisation stage is carried out at speed of carbonising gas flow of below 30 litres per minute under normal conditions per kg of calcium hydroxide in process of deposition. Concentration of precipitated calcium carbonate is increased without using an agent that promotes dispersion or with application of a cationic disperser under quite moderate or mild conditions, which do not cause considerable damage of aggregates/agglomerates, until concentration from 15 to 50% is achieved, preferably in the range from 20 to 30%, most preferably - from 23 to 26 wt % of hard substances.

EFFECT: invention makes it possible to produce porous stable agglomerates of precipitated calcium carbonate.

22 cl, 5 dwg, 9 tbl, 12 ex

FIELD: textile fabrics, paper.

SUBSTANCE: method is related to production of coated paper or cardboard. Method includes application of pigment composition as coating on at least one side of paper or cardboard web. Specified pigment composition is water dispersion, which includes optionally aggregated colloidal particles of silicon dioxide or aluminium silicate as pigment particles, which are prepared from alkali metal silicate by ion exchange or pH reduction and having surface area of approximately from 30 m2/g to approximately 450 m2/g. Coating contains also at least one cationic component selected from group that consists of water-soluble aluminium salts and cationic polymers with molecular weight from approximately 2,000 to approximately 1,000,000 and charge density from approximately 0.2 mEq/g to approximately 12 mEq/g, in which at least approximately 0.4 g of pigment particles from pigment composition is applied on m2 of coated side of paper or cardboard web. Invention is also related to paper or cardboard produced by this method. It is also related to composition of above mentioned pigment in the form of water dispersion, which includes less than approximately 3 wt % of organic binders and to method of above mentioned pigment composition production, in which mixing is done to produce water dispersion in order to avoid gel formation and deposition.

EFFECT: improvement of printing and strength properties of coating, and also lower scuffing of paper.

26 cl, 5 tbl, 4 ex

FIELD: textiles; paper.

SUBSTANCE: composition is designed for refining fibrous material, can be used in the production of enamelled cardboard and paper and relates to the cellulose-paper industry. The composition contains a modified pigment and a water soluble binding substance. The pigment is calcium sulfoaluminate, modified starch or polyvinyl alcohol with mass ratio content of 0.5-1.5. The water soluble binding substance is starch.

EFFECT: resistance to fluffing and whiteness of the coating with considerable lowering of consumption of the binding substance when making the composition.

1 tbl

FIELD: textiles, paper.

SUBSTANCE: solution is meant for rifining of fibrous material. It pertains to the field of paper manufacturing and cardboard during manufacturing of chalk-overlay types of cardboard and paper. The solution consists of water soluble binder. A mixture of calcium salfoaluminate and kaolin, modified starch or polyvinyl spirit is used as the pigment. The technical result is high stability to picking, whiteness, colour perception and smoothness. The solution enhances adhesion of the coating to the base (cardboard or paper), which makes it possible to use the refined coating as a sub-layer when dual or tri-coating cardboard or paper, with obtaining products with a given range of characteristics.

EFFECT: obtaining of a solution for refining material for production of paper and cardboard during production of chalk-overlay types of cardboard and paper.

1 tbl, 1 exr

FIELD: light industry; composition of decorative coats for wallpaper; manufacture of pearly ink for intaglio printing on wallpaper.

SUBSTANCE: composition of proposed printing ink for wallpaper contains 16-16.5 mass-% of pearly pigment; 12-12.5 mass-% of ethyl alcohol; 46-46.4 mass-% of binder - acrylic latex of butyl acrylate copolymer (19-21%) and methacrylic acid (10-12%) and water; copolymer acrylic latex is produced by method of radiation emulsion polymerization of butyl acrylate, vinyl acetate and methacrylic acid under action of ionizing radiation at dose rate of 0.05-0.1 g/s to absorbed doses of 1.5-2 kgr.

EFFECT: avoidance of lamination of ink; easily washable ink; enhanced heat resistance of ink.

1 tbl, 2 ex

FIELD: chemical industry; printing industry; powder metallurgy industry; cosmetic industry; other industries; production and application of the highly anticorrosive metallic pigments.

SUBSTANCE: the invention is pertaining to production of the of the highly anticorrosive metallic pigments similar to laminas, which may be used in production of the printing ink, plastic materials, cosmetics, the powder coatings and in other branches of industry. The pigments have on their surfaces: the metallic substrates similar to the laminas and treated with the compounds of the phosphoric acid and-or the compounds of the boric acid; one or more layers of the coatings consisting of one or more hydrated oxides of the metals of one or more metals selected from the group, which includes silicon, aluminum, zirconium, titanium and tin. On the basis of the highly corrosive metallic pigments similar to laminas it is possible to produce the interferential colored pigments. The invention allows to increase the anticorrosive resistance of the metallic pigments at the expense of saving without the faults of the initial surface smoothness of the similar to the laminas metallic substrates, to increase the homogeneity and density of the layers of the hydrated oxides of the metals.

EFFECT: the invention ensures the increased anticorrosive resistance of the metallic pigments, saving the initial surface smoothness of the similar to the laminas metallic substrates, the increased homogeneity and density of the layers of the hydrated metals oxides.

40 cl, 9 ex, 4 tbl, 8 dwg

FIELD: pulp-and-paper industry, in particular, paper sheet having surface feeling hash to the finger, and method for applying coating onto paper sheet.

SUBSTANCE: paper sheet of such structure may be used for manufacture of paper or plastic medium for carrying of printed information, paper or plastic package, cover used in stitching and binding processes, or cardboard or plastic carton having surface feeling hash to the finger. At least one side of paper sheet is coated with layer containing non-compressible microscopic particles of non-gelatinized starch grains, or said particles are produced by grinding of plastic material. Method involves treating at least one side of paper sheet with water-based composition containing non-compressible microscopic particles which are made three-dimensional and rounded, binder, and filler; drying paper sheet after treatment. Particles are non-gelatinized starch grains, or particles are produced by grinding of plastic material. Method allows paper sheet to be produced, which has roughness coefficient Kd below 0.5.

EFFECT: simplified method and improved quality of paper sheet.

17 cl, 16 dwg, 1 tbl, 3 ex

FIELD: chemical industry; printing industry; other industries; methods of production of the composition of the paint including the optically changeable pigments.

SUBSTANCE: the invention may be used in production of the optically changeable pigments. The optically changeable pigment includes the stratified set composed of the different materials, in which, at least, one of the layers represents the reflecting layer and, at least, one of the other layers represents the dielectric layer. At least, one of the surfaces of the indicated layers is subjected to the chemical action. The indicated materials also include, at least, one of the layers, which represents the semitransparent metallic layer made out of chromium and also one or more metals and-or their inorganic compounds. At that the metal and-or its inorganic compound are subject to corrosion. The subjected to the chemical action surface of the reflecting and dielectric layer along the edge of the layering block of the edge structure of the pigment is coated with the passivating agent, which is selected from the group consisting of the organic esters and the fluorinated organic esters of the phosphoric acid, having the following structural formula: (Rf-CH2-CH2-O)xP(O)(OH)y, where Rf=F-(CF2-CF2)z, х=1 or 2, у=2 or 1, х+у=3, z=l-7. The composition of the printing paint includes the binding system, water and the optically changeable pigment. The invention allows to diminish oxidation of the metallic layers and dissolution of the dielectric layers of the optically changeable pigment and to use it in the compositions of the printing paint.

EFFECT: the invention allows to diminish oxidation of the metallic layers and dissolution of the dielectric layers of the optically changeable pigment and to use it in the compositions of the printing paint.

22 cl, 7 ex

FIELD: chemistry.

SUBSTANCE: in order to obtain ground mineral material a) at least one mineral material which is optionally in form of aqueous suspension is taken, b) said material is ground, c) the ground material obtained at step (b) is optionally sieved and/or concentrated, d) the ground material obtained at step (b) or (c) is optionally dried. The grinding step (b) is carried out in the presence of zirconium oxide grinding beads containing cerium oxide, having cerium oxide content between 14 and 20% of the total weight of said beads, preferably between 15 and 18% of the total weight of said beads, and more preferably approximately 16% of the total weight of said beads. The average size of grains after sintering grains which form said beads with average diameter less than 1 mcm is preferably less than 0.5 mcm and more preferably less than 0.3 mcm. The obtained ground mineral material is in form of aqueous suspension, wherein the weight ratio ZrO2/CeO2 is equal to 4-6.5, preferably 4.6-5.7 and more preferably 5.3.

EFFECT: invention reduces contamination of the ground material due to wearing of apparatus used when grinding.

40 cl, 2 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: crude mixture for producing heat-resistant inorganic pigments includes a carrier and colouring additives and has the following composition in wt %: alumina or wastes from producing electrical insulators - scrap glased and unglased porcelain insulators or scrap dried unburnt insulators - 40-95; oxides and/or carbonates and/or oxalates of metals - 5-60. To obtain pigments, the crude mixture of the said composition undergoes dry grinding and mixing in a periodic action device to fineness which enables passage through a sieve of 10000 holes/cm2 for 1-4 hours. The obtained mixture then undergoes thermal treatment to temperature 650-1340°C and that temperature is maintained for 1.5-4 hours. Further, the furnace is cooled to room temperature. The obtained mixture undergoes drying grinding in the periodic action device again for 1-8 hours until obtaining not more than 1.0% residue on sieve 20000 holes/cm2. The apparatus for producing pigments has a revolving housing with an inner lining which is partially filled with grinding bodies, a loading-unloading device and a drive. The housing has conical faces and is fitted with a dust-protective cover outside, which is joined to the container for the end product which is placed under the housing. The inner lining is made from polyurethane, and grinding bodies have a steel core with an outer polyurethane coating.

EFFECT: invention enables to obtain heat-resistant pigments with a wide colour gamma using wastes from production of electrical insulators, and also increases environmental safety.

4 cl, 2 dwg, 2 tbl, 17 ex

FIELD: chemistry.

SUBSTANCE: invention relates to an aqueous colloidal suspension of carbon black which can be used in ink, such as jet printing ink, lacquer, printing dyes, latex, in textile and leather products, in adhesives, silicon materials, plastic materials, concrete and in construction materials. Described is an aqueous colloidal suspension of carbon black which contains carbon black, an azocompound of general formula 1 and water. The said carbon black suspension is obtained by dispersing carbon black and an azocompound of general formula 1 in water.

EFFECT: carbon black suspension has high degree of dispersion and low flocculation capacity which gives ink made from the said suspension high optical density.

17 cl, 3 dwg, 6 tbl, 6 ex

FIELD: chemistry.

SUBSTANCE: invention can be used in pigments production. The method of powders calcination for ceramic pigments production involves powder agglomeration for the purpose of individual powder particles aggregation into structures with greater size and following drying of agglomerated powders. The agglomerates are placed into continuous vertical furnace and let be fallen due to gravitation. The calcinated agglomerates are gathered at the furnace outlet.

EFFECT: invention allows using of the starting material in the form of pellets without deterioration of the end-product pigments characteristics, to exclude the clogging up of the calcination tube installed inside the furnace and to provide the easy flow of the powders in the furnace.

8 cl, 1 ex

FIELD: chemistry.

SUBSTANCE: natural mechanically milled iron (III) oxide of lamellar structure at least 50 wt %, preferentially 75 wt %, contains particles sized 10 mcm and less in amount, at least, 50 wt %, preferentially 70 wt %, particularly preferentially 90 wt %. The ratio of thickness to maximum diametre of iron (III) oxide plates is 1:5, preferentially 1:10. To produce such iron (III) oxide, it is mechanically milled in an impactor or a jet-type mill. Iron (III) oxide resulted from mechanical milling, is separated by size grade, e.g. by an air separator. Iron (III) oxide can be used in lacquering for a base corrosion protection, mechanical load protection, UV and IR protection, for decorative coating, and also as an extender for polymeric and ceramic materials.

EFFECT: possibility to prepare highly dispersed lamellar particles of natural iron oxide.

15 cl

FIELD: chemistry.

SUBSTANCE: invention can be used in paint and varnish, cosmetic and other industries. Offered aluminium pigments are at least partially covered with greasing and having a) water spread coefficient within 40000 and 130000 cm2/g; b) average thickness h within less than 100 to 30 nm calculated from water spread coefficient and integral distribution h50 by data processing on thickness of scanning electron microscopy; c) relative width Δh of thickness distributions determined by data processing on thickness of scanning electron microscopy and calculated by corresponding relative frequencies integral curve by formula: 70% to 140%; d) form-factors d50/h more than 200; e) roughness degree calculated by specific surface area measured by BET method and spread coefficient according to the following formula: BET value/2 spread coefficient, from 0.30 to 0.9. Method of production of these pigments, as well as varnishes containing these pigments is offered.

EFFECT: production of very thin aluminium pigments without adhesive polymer film having excellent spreading capacity, high gloss value and improved metallic appearance, as well as reduced agglomeration tendency.

26 cl, 10 ex, 4 tbl, 5 dwg

FIELD: chemistry.

SUBSTANCE: invention pertains to the method of obtaining low-dimensional filling materials, which can be used in engineering materials for making composite materials with given functional characteristics. The method involves grinding the raw materials of the layer mineral and thermal treatment of the ground up dispersed particles. Thermal treatment is done by putting the dispersed particles into a non-oxidising thermal gas stream with density of 3·106-8·107 W/m2 for a period of 10-4-10-3 s. The above mentioned stream, containing dispersed particles, is applied to a substrate in form of a steel sheet, heated to 20-100°C. The obtained particles are collected and cooled down to 100-120°C.

EFFECT: invention allows obtaining a filling material with size of not more than 10 nm, with low energy consumption, and is effective when making polymer nano-composites.

3 tbl

FIELD: industrial inorganic synthesis.

SUBSTANCE: method of preparing high-quality titanium nanoxide with particle size 10 to 100 nm comprises generation of gas plasma, introducing gas plasma flow, oxygen, and titanium tetrachloride vapors, oxidation of titanium tetrachloride with oxygen in synthesis zone to form titanium dioxide and chlorine, and quenching synthesis products in supersonic nozzle by way of transforming subsonic synthesis products flow escaping synthesis zone into supersonic flow, which is then expanded and cold quenching gas is injected thereto. Prior to enter synthesis zone, titanium tetrachloride is mixed with oxygen at molar ratio between 0.05 and 0.25, respectively. Cold quenching gas is injected when supersonic flow is expanded inside expanding portion of supersonic nozzle having opening angle 10-15°.

EFFECT: improved quality of titanium nanoxide.

1 dwg, 2 tbl

FIELD: methods and plants for increase of volume density of aerated powders.

SUBSTANCE: proposed method of compacting the powder containing oxide or phosphate of metal consists in placing the powder in container and increasing the pressure in its area above atmospheric pressure sufficient for compacting the powder before diffusion of considerable part of gas into powder. Powder containing oxide or phosphate of metal is placed in container and its volume density is increased. Then, concentrated suspension of pigment which is titanium dioxide is prepared. Specification gives description of plant proposed for increase of volume density of powder containing oxide or phosphate of metal and plant for increase of volume density of aerated loose pigment which is just titanium dioxide.

EFFECT: increased volume density of aerated powder; improved consistency; facilitated dispersion in latex paints.

22 cl, 6 dwg, 3 tbl, 8 ex

FIELD: varnish-and-paint industry.

SUBSTANCE: process of producing titanium dioxide pigment according to chloride technology comprises oxidation of titanium tetrachloride with oxygen or oxygen-containing gas in plasmachemical reactor followed by cooling of reaction products in tempering chamber and subsequent multistep fine grinding of intermediate product, titanium dioxide, by way of affection with supersonic gas flow at 100-500°C and ratio of gas mass intake to titanium dioxide mass intake = 0.2. In the first step of titanium dioxide fine grinding, treatment of titanium dioxide is performed with a dry gas supplemented by vapor of organic or organosilicon modifier having in its molecule at least one of the following functional groups: -OH, -NH2, NH, SH at mass intake of modifier representing 0.1-2.0% of the mass intake of titanium dioxide.

EFFECT: improved quality of titanium dioxide pigment and simplified process of production thereof.

1 dwg, 1 tbl

FIELD: chemistry.

SUBSTANCE: present inventions relate to a method of producing precipitated calcium carbonate (PCC) and the design of a low-power reactor system for realising the method such that, the amount of dry residues in the PCC product can be increased to 35% or more without a dehydration step. The disclosed method involves steps for bringing calcium hydroxide into contact with a carbon dioxide-containing gas in parallel or two or more separate reaction vessels in order to form calcium carbonate. Calcium oxide, lime or dry calcium hydroxide or a combination of any of the three components are also added to a portion of the obtained mixture of calcium hydroxide and calcium carbonate. When used in the production of PCC, the reactor system has at least one reactor vessel with an optional water inlet and gas inlet and at least one recirculation reservoir for inlet of components and optional water inlet.

EFFECT: use of the disclosed method and device ensure efficient and economical production of PCC with a given structure and high content of dry residues.

21 cl, 8 dwg, 9 ex

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