Compositions of calcium carbonate and pigments for paper compounds by which degree of print-through is reduced

FIELD: textiles, paper.

SUBSTANCE: composition comprises a mixture of one of the two porous stable aggregates and precipitated calcium carbonate (PCC) called grade B OCC or grade C OCC, in combination with the second OCC of non-equal-faced type (OCCNT) - the pigment of fine grinding. The ratio of grade B OCC or grade C OCC and OCC of non-equal-faced type OCCNT is selected in the range from 90/10% to 10/90% by dry weight. The content of dry weight of pigments is selected in the range from 0.3% to 5.0% by dry weight of the finished paper product. Depending on the granulometry of two OCC of fine grinding the said mixture may contain a pigment and/or filler of coarser grinding. The main criterion of selection of the pigment of "coarser grinding" is that it should have a granulometry which does not have influence on the significant deviation in the number of particles smaller than 0.2 microns, preferably less than 0.3 microns, more preferably less than 0.5 micron, the most preferably less than 1 micron.

EFFECT: composition enables to eliminate the print-through through the layer of light thin paper such as newsprint and to improve the technical properties of the paper sheet.

24 cl, 4 dwg, 1 tbl, 8 ex

 

The present invention relates to mixtures of two specific porous, stable aggregate of substances and pigments (precipitated) calcium carbonate (COC) is rather coarse with the third component coarser, which may be a pigment or filler, such as natural calcium carbonate (powdered) or (most preferably) precipitated calcium carbonate (COC), or, optionally, but less preferably: talc, kaolin, titanium oxide (TiO2), clay and other pigments or fillers used in the paper industry and, in General, well-known experts in this field. Depending on the granulometry of the two VBEs the third component of a larger grinding can be omitted.

Technical problem

In the paper industry there is a certain need in pigment composition, it contains calcium carbonate (calcium carbonate) in a special combination, and possibly in combination with other pigments or fillers, to improve complicated, or fine-grained and sophisticated technical properties of the finished paper sheet, for example, "viewed through the imprint" or "coming through imprint in the use of paper, like newsprint, light thin paper or light-weight paper that does not contain revenage fiber, sverhkachestvennoy magazine paper, etc.

These properties are well known to specialists in this field, and a detailed description can be found in the APPENDIX A in the domain relating to newsprint.

In particular, it would be very interesting to create for the industry such a composition, which could improve these properties and, if possible, at a lower cost.

A brief description of the preferred option of carrying out the invention

In the first embodiment, the invention proposed a composition comprising a mixture of one of the two porous, stable aggregate of substances and the OCC rather coarse (2-10 µm), called the OCC brand B or brand C, in combination with a second, special pigment COC neravnovesnogo type (ACCNT), described below.

You can also use R-JCC or a JCC and a third component.

According to the invention, the above ratio may be appropriately selected in the range from 90/10 to 10/90 parts per hundred parts (%) dry matter, namely: 80/20 and 20/80.

The most representative examples are as shown below as an example:

JCC brand C/ACCNT (ratio = 50/50);

JCC brand B/ACCNT (ratio = 70/30); and

JCC brand B/ACCNT (ratio = 50/50)

(ratios are shown as a percentage of dry mass).

At present the it application and in the claims, the word "containing" understand, except when stated otherwise, the composition, the composition, the mixture may contain the usual additives that do not have a significant impact on the functioning of the main component used according to the present invention.

Each proposed invention the composition may contain conventional additives known and used in this paper industries, no significant detrimental effects.

The list of such conventional additives well known to specialists in this field.

In the most preferred mode of carrying out the invention proposed composition containing either the JCC brand A, or the OCC brand B, in combination with a second pigment ACCNT, as mentioned above, in a ratio of from 90/10 to 10/90 dry mass, and in combination with the third special pigment more coarsely.

The percentage dry weight of pigments, as proposed in the invention, of the total mass of the mixture is preferably selected in the range from 0.3% to 5.0%, most preferably in the range from 0.5% to 3.0% of the dry weight of the finished paper product, and even more preferably in the range from 1.0% to 2.0%. In laboratory tests was chosen such percentage in the range of 2% and, respectively, to 4%, for practical reasons.

The percentage of pigment coarser of the total m the ssy three components JCC brand B or brand C + ACCENT + pigment coarser, it must be in the range below 10 wt.%, and preferably in the range from 0.1 wt.% to 10.0 wt.%, preferably from 0.5 wt.% to 7.0-10.0 wt.%, and most preferably in the range from 2 wt.% up to 7 wt.%.

The person skilled in the art is able to adapt these examples to other structures.

Further, in particular, in tables, a mixture consisting of two or three components according to the invention, are called "primary"because the examples were performed using recovered paper composition based on the newsprint, and since these components were fresh fillings.

Other pigments, such as calcium carbonate of any kind, clay, etc. derived from recovered paper composition based on newsprint, called "support".

The invention can be better understood after reading the subsequent examples, not limiting its scope, the results of which are presented in the attached tables.

As explained below, the main selection criteria mentioned pigment "coarser" is that he must have granules in which he has no significant deleterious effects when it is added to the mixture JCC brand B (or the OCC brand C) ACCENT (all options shown in the examples below and in Table 1), on the most delicate part is granulometrically parameters of the mixture and, in particular, should not make any significant deviation in the number of particles smaller than 0.2 μm, preferably should not make any variance in the number of particles smaller than 0.3 microns, more preferably should not make any variance in the number of particles smaller than 0.5 micron, and most preferably should not make any variance in the number of particles smaller than 1 micron.

Any filler or pigment that matches the above criteria, acceptable, and can be tested in the usual way by specialists in this field, including those fillers or pigments, which are used in the paper industry or in a similar industry, for example, the OCC - natural ground calcium carbonate (PMCC), clay, kaolin, dolomite, titanium oxide (Ti02and so on

Table 1 presents Data on pigment", referenced in the experiments.

In the left column of Table 1 presents all the values and properties, which is the standard, well known to experts in this field, for example: specific surface area by BET (BET - method of determining the specific surface area of solid particles along the isotherm of vapors or gases) determined according to ISO 9277 (ISO - international organization for standardization); or the distribution of particle sizes determined with the use of device Sediraph TM5100 company MicromeriticsTM.

Under the viscosity B here understand the value of viscosity measured by Brookfield using a Brookfield viscometer at 25°C and at a corresponding speed of rotation of the spindle.

The surface charge was measured by well-known methods, and it is not particularly significant for understanding the present invention. However, the person skilled in the art can appreciate, which can be very useful when considering printing water-based ink containing charged dyes, if the consumer wants to use (by default) ink jet printer using an ink water-based, although for flexographic printing (used for printing Newspapers), you can also use such ink.

Whiteness R - 457 is also well known to specialists in this field, and the above-mentioned degree of whiteness R - 457 determined according to DIN 53140, using the device Datacolor ElrophoTM3300 (DIN - German standards Institute, member of ISO).

Dispersing agent selected from conventional substances known and is used in this paper industries, for example, polycarboxylate etc. It is not particularly significant for understanding the present invention. However, if through polymer provides specific surface C is a number, promoting adsorption of certain printing inks, it can be very significant for understanding: again, use the explanations given above.

The oil absorption is determined by known methods, and it is not particularly significant for understanding the present invention.

HYDREX(TM) P is a commercially marketed product, representing a silicate of sodium (Na), which is the well-known standard substance. In the analysis of tables, namely, Table 1 Data on pigment", suddenly it turns out that proposed in the invention compositions have a much smaller value BET than HYDREX P, with better or the same properties, as is evident from tables.

Test 1 refers to chalk treated with H3PO4with a solids content of 38 wt.%.

Test 2 refers to the marble treated with H3PO4also with a solids content of 38 wt.%.

Test "C 3" refers to the product "JCC brand C".

Test "INV 4 is the preferred composition according to the invention, a mixture of the JCC brand C and ACCNT 50/50 (percentage of dry mass).

Test "B 5" refers to the product "JCC brand B".

The test "S 6" refers to "ACCENT" (COC neravnovesnogo type).

Experiments (Exp.) 1 and 2 are experiments which according to this invention:

experiment 1 corresponds to the ratio of 50/50 (percentage of dry mass) of the mixture according to the invention, the OCC brand B/ACCNT.

Experiment 2 corresponds to the ratio of 70/30 (percentage of dry mass) of the mixture according to the invention JCC brand C/ACCNT.

Experiment 3 corresponds to the comparative product, a mixture of 50/50 (percentage dry weight) mixture of JCC brand B and chalk.

Test 7 - a comparative experiment carried out with the use of natural (ground) of calcium carbonate, representing 100%Mel.

Test 8 - another comparative experiment conducted using ground calcium carbonate.

Table 2. Test conditions

Test conditions in the manufacture of paper in the laboratory, in total, are presented in Table 2.

OTCBFM (DIP), as is known, means peeled from the printing ink, paper of a fibrous mass.

Retention additive (additive) may differ from that used additives PolyminTMand may be (without limitation) any monocomponent, or may be a so-called "dual" system, for example, without limitation, acrylic copolymers (acrylamide), and can be restraint additives such as bentonite or starch, or a derivative of starch, etc. as is well known with what ecialists in this field.

Table 3. The content of the filler (Secondary/Primary)

Auxiliary (i.e., classical) a mixture of the pigment/filler is a mixture consisting of CaCO3- 3.5 wt.% and clay - 7.5 wt.%, components of the total a level corresponding to 11 wt.%, considered as the minimum acceptable level.

For comparison, in addition to these 11 wt.% classic filler was added 2 wt.% from the total mass of the mixture (see left column) or, respectively, 4 wt.% (see right-hand column) fillers (fillers)indicated at the bottom of the Table that corresponds to the tests and experiments are presented in Table 1.

The percentage specified in Table 3 refers to the total content (wt.%) pigments in the total mass: paper fibrous mass + filler (bulking).

As for how the introduction of fillers in paper fibrous mass, or in the feedstock, the order of introduction is not crucial; however, it is preferable to introduce the proposed invention "primary" mixture of two or three pigments in paper fibrous mass which contains at least the minimum total level of 11% or more. For completeness <pattern> it should be noted that the impact of the primary filler is not related to the number of auxiliary napolnitel is, it also affects 100%fresh paper fiber that does not contain an auxiliary pigment.

You can add proposed invention the mixture of pigments in a single operation, or the introduction, or in the course of several processes introduction to various areas of the production line. You can also prepare a premix of various fillers, including premixes part of the classic ("the subsidiary") fillers with a partial or full amount of the proposed invention ("primary") fillers. Several of these premixes can be introduced at various locations along the production line. The introduction of the premix from the primary filler with the auxiliary filler in OTCBFM (DIP) is not really practical, as an auxiliary pigment is already in a fibrous composition OTCBFM (DIP), but can be used.

It is well known in the industry that the person skilled in the art can find the place (s) of introducing it, bearing in mind the existing equipment, the desired coefficient of internal friction, duration of contact, etc.

Table 4. The optical density

Struggling through the imprint"

This table presents the results obtained when applying the above compositions, Ho is e implementation of the described tests in the manufacture of paper.

Struggling through the imprint" is a property, the measurement of which is described in detail in APPENDIX A and in European patent EP 1712597.

Table 5. Visible through the imprint"

This table presents the results obtained when applying the above compositions, in the implementation of the described tests in the manufacture of paper.

Visible through the imprint" is a well - known property, the measurement was carried out according to the procedure described in APPENDIX A.

The present invention also covers paper fibrous mass, or feedstock, for forming a paper sheet, namely: paper industrial complex, characterized in that they contain an effective amount of the compositions of the pigment mixtures according to the invention, as described above, in an effective amount, that is also described above.

The invention also comprises a paper product made from the above-described fibrous paper pulp, or feedstock, and, as mentioned, it can also be used with application of 100%wood fiber and pulp, mixtures of wood fiber supply and OTCBFM (DIP)/OTCBFM (DIP), most likely also using 100%fresh pulp and paper the pulp.

Appendix a

Perforation of the impression in newsprint

The reason for punching stamp in g is senoi paper associated with opacity porosity, ash content, surface roughness and surface density of paper.

As printing inks dry in the course of a purely physical process, and not during the oxidation process, as is the case for rotary offset printing, or during the process of evaporation of volatile substances, as in web offset printing/offset printing with heat, it is the migration of mobile substances, such as mineral and vegetable oils in the paper, and they are absorbed by the paper fibers and fillers. If the proportion of migratory oils becomes too large (too large proportion of the content of the printing ink), and the layer of the inner surface of the paper is too thin, the oil reaches the other side of the paper and causes an increase transparency.(1)

Using this test method, it is possible to exercise control over the manufacture of paper. You can get a good indication of definitions of quality variations in the manufacture of paper, as the amount of ink and pressure when printing is so high that a clear breaking of the seal should be visible, and thus, weak or strong puncture seal can also be recognized.

This method could not be used as a standard test in the testing laboratory of the Authors, because they have not sought control of the funds workmanship, and conducted a comparison of paper with different surface density obtained from various manufacturers, with each other most objective way. In addition, the Authors had to work, exploring the impact of the most widely practically used amounts of inks and pressure when printing.(2)

As the Authors sought to obtain data that would be most reliable in normal practice when printing on various Newspapers, by this method it was possible to set the amount of printing ink, in agreement with the commonly practiced pressure when printing, to achieve a desired optical density.

However, any breaking of the seal is the result of what we used paper, not the quantity of used ink.

If used too much ink and too much pressure when printing, using paper with a lower surface density automatically led to a bad result.

If you use too much ink and too much pressure when printing, using paper with a lower surface density automatically leads to a bad result.

Notes:

(1) However, the document was not taken into account the large share of newsprint, which today print newspaper, using flexography, which can be applied printing ink water-based and can be adapted oxidative processes.

(2) When conducting such tests in laboratory conditions, it was not meant that they will be absolutely standard, and tests were focused on the comparison of characteristics of samples of paper printed with the use of known acceptable and unacceptable options paper. For this reason, the amount of ink and pressure when printing regulated in accordance with the surface density of the paper and the criteria applied, but adhered to the rules for the use of criteria as closely as possible approached used in practice.

1. Compositions containing calcium carbonates, pigments and/or fillers for paper compositions, by means of which reduce the penetration of the imprint, including
the appearance of "visible through the imprint" or "coming through stamp", characterized in that they contain
a mixture of one of the two porous, stable aggregates rather coarse precipitated calcium carbonate (COC), called the OCC brand or JCC brand With, in combination with the which, special OCC neravnovesnogo type (ACCNT) - pigment, and that
the ratio of the JCC brand or COC stamps, and the OCC neravnovesnogo type ACCNT chosen in the range of from 90/10% to 10/90% (based on dry weight and is the fact that
the percentage dry weight of pigments chosen in the range from 0.3% to 5.0% of the dry weight of the finished paper product,
moreover, the specified JCC marks, stamps or ACCNT have the following options:

JCC-JCC-InACCNT
Specific surface area (m2/g)75.970.58.8
The distribution of particle sizes
<5 μm (%)999898
<2 μm (%)666664
<1 μm (%)353228
<0.5 µm (%)161212
<0.2 μm (%)1165

2. The composition according to claim 1, characterized in that they contain a mixture of 50/50, based on dry weight, the OCC brand/ACCNT with the following properties:

Specific surface area (m2/g)42.9
The distribution of particle sizes
<5 μm (%)99
<2 μm (%)72
<1 μm (%)27
<0.5 µm (%)8
<0.2 μm (%)3

3. The composition according to claim 1, characterized in that they contain a mixture of 50/50, based on dry weight, the OCC brand/ACCNT with the following properties:

Specific surface area (m2/g)42.0
The distribution of particle sizes
<5 μm (%)99
<2 μm (%)70
<1 μm (%)37
<0.5 µm (%)18
<0.2 μm (%)8

4. The composition according to claim 1, characterized in that they contain a mixture of 70/30, based on dry weight, the OCC brand/ACCNT with the following properties:

Specific surface area (m2/g)56.7
The distribution of particle sizes
<5 μm (%)99
<2 μm (%)69
<1 μm (%)36
<0.5 µm (%)16
<0.2 μm (%)7

5. The composition according to claim 1, characterized in that the mixture of these two specific (precipitated) calcium carbonate (COC) - by the pigment as tattoo the brand B or brand C and ACCENT, contain the third component is more coarse, representing a pigment or filler.

6. The composition according to claim 5, wherein said third component is more coarsely extracted from the natural calcium carbonate (ground), or precipitated calcium carbonate (COC), or talc, kaolin, titanium oxide (TiO2), clay or dolomite.

7. The composition according to claim 6, characterized in that the third component is more coarse is a precipitated calcium carbonate COC.

8. The composition according to claim 1, characterized in that the ratio of the JCC of the brand or the OCC brand/ACCNT chosen in the range of from 80/20 to 20/80% (based on dry weight.

9. The composition according to claim 1, characterized in that the percentage on the total dry mass of the proposed invention mixtures of pigments chosen in the range from 0.5% to 3.0% of the dry weight of the finished paper product.

10. The composition according to claim 1, characterized in that the percentage on the total weight of the dry mixture according to the invention is chosen in the range from 1.0% to 2.0% of the dry weight of the finished paper product.

11. The composition according to claim 9, characterized in that the said percentage is 2.0%.

12. The composition according to claim 1, characterized in that the said percentage is 4.0%.

13. The composition of item 12, characterized in that the main criterion of choice in manutoo pigment "coarser" he must have granules in which he has no significant deleterious effects when it is added to the mixture JCC brand B (or the OCC brand C) ACCNT, on the most delicate part of granulometric parameters of the mixture and does not make any deviation in the number of particles smaller than 0.2 μm.

14. The composition according to item 13, wherein the pigment coarser does not introduce significant variations in the number of particles smaller than 0.3 microns.

15. The composition according to item 13, wherein the pigment coarser does not introduce significant variations in the number of particles smaller than 0.5 micron.

16. The composition according to item 13, wherein the pigment coarser does not introduce significant variations in the number of particles smaller than 1 micron.

17. The composition according to claim 1, characterized in that the proportion of pigment coarser from the total amount of the three components of the OCC brand B or brand C + ACCENT + pigment coarser must remain less 10 wt.%.

18. The composition of 17, characterized in that the proportion of pigment coarser from the total amount of the three components of the OCC brand B or brand C + ACCENT + pigment coarser ranges from 0.1 wt.% up to 10 wt.%.

19. The composition of 17, characterized in that the proportion of pigment coarser from the total amount of the three components of the OCC brand B or brand C+ ACCENT + pigment coarser ranges from 0.5 wt.% 7-10 wt.%.

20. The composition of 17, characterized in that the proportion of pigment coarser from the total amount of the three components of the OCC brand B or brand C + ACCENT + pigment coarser ranges from 2 wt.% to 7 wt.%.

21. Paper fibrous mass or raw materials for molding a sheet of paper, characterized in that it contains an effective amount of the compositions according to claim 1 in the range from 0.3% to 5.0% of the dry weight of the finished paper product.

22. Paper fibrous mass or raw materials for forming a paper sheet according to item 21, characterized in that it contains an effective amount of the above compositions in the range from 0.5% to 3.0% of the dry weight of the finished paper product.

23. Paper fibrous mass or raw materials for forming a paper sheet according to item 21, characterized in that it contains an effective amount of the above compositions in the range from 1.0% to 2.0% of the dry weight of the finished paper product.

24. Paper product made from paper fiber supply or source of raw materials for item 21.



 

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13 cl, 10 dwg, 1 tbl, 6 ex

FIELD: chemistry.

SUBSTANCE: invention can be used to produce a pigment suitable in making paper for ink-jet printing. Precipitated calcium carbonate is obtained by mixing quicklime with water in a reactor or a tank with a mixer, followed by filtration of the calcium hydroxide suspension to remove all residual contaminants and/or non-reactive quicklime. The filtered suspension is then fed into a stainless steel reactor fitted with a mixer. Temperature is kept in the range of 10-70°C, after which the suspension is fed into a carbonisation reactor, where a carbon dioxide-containing gas is bubbled through the suspension. The carbonisation step is carried out at carbonisation gas flow rate of less than 30 litres per minute per kilogram of calcium hydroxide during precipitation under normal conditions. The suspension is removed from the tank when conductivity reaches the minimum level and pH drops below 8, wherein large particles are removed through a filter. The obtained calcium carbonate can be used as a pigment.

EFFECT: invention improves the quality of ink-jet printing while reducing the cost of production of paper for ink-jet printing.

15 cl, 5 dwg, 17 tbl, 9 ex

FIELD: chemistry.

SUBSTANCE: invention relates to organic fibres having a mineralised surface, which includes organic fibres having a length in the millimetre range, the surface of which is at least partially coated with finely dispersed nanoparticles alkali-earth metal carbonates using binding materials based on copolymers which contain, as monomers, one or more dicarboxylic acids or one or more monomers from a group of diamines, triamines, dialkanolamines or trialkanolamines, and epichlorohydrin, a method of producing such organic fibres having a mineralised surface, aqueous suspensions thereof, use thereof in paper production, in finishing paper surfaces, plastic surfaces, cement and clay, in paint and lacquer, and use of binding substances according to the present invention to coat organic fibres with nanoparticles of alkali metal carbonates.

EFFECT: providing fibre-pigment or filler composites, as well as aqueous suspensions thereof, which not only have good optical properties and good printing properties, but also have an insignificant or no tendency to segregate in treatment conditions thereof, and also enable to obtain paper or cardboard having high content of filler of nanoparticles which are otherwise hard to hold due to their fineness.

37 cl, 8 tbl, 13 dwg

FIELD: textiles, paper.

SUBSTANCE: paper base is intended for internal and external sizing, which has high dimensional stability, and can be used in pulp and paper industry. Paper base contains cellulose fibers, at least one filler, and sizing agent. At that the paper base has a coefficient of hygroextension from 0.6 to 1.5%. The Scott internal constraint in the transverse direction is not greater than 300 J/m2, and/or Scott internal constraint in the longitudinal direction is not greater than 300 J/m2. Also a method of manufacturing the paper base and versions of paper base are proposed.

EFFECT: increased dimensional stability and durability of the surface of the paper base.

26 cl, 24 dwg, 15 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention can be used in making paper products. The gypsum product essentially consists of undamaged crystals, having weight-average diameter D50 0.1 - 2.0 mcm and particle size distribution width less than 2.0. The shape factor of the crystals is equal to at least 2.0 and the aspect ratio is equal to 1.0-10. The gypsum product is obtained by reacting calcium sulphate hemihydrate and/or calcium sulphate anhydrite and water in the presence of a crystal habit modifier. The reaction mixture has dry substance content of 50-84 wt %. The crystal habit modifier is used in amount of 0.01-5.0% of the weight of the calcium sulphate hemihydrate and/or calcium sulpohate anhydrite and is selected from a group consisting of ethylenediamine succinic acid, iminodisuccinic acid, ethylenediamine tetraacetic acid, diethylenetriamine pentaacetic acid, nitrilotriacetic acid, N-bis-(2-(1,2-dicarboxyethoxy)ethylasparticacid, di-, tetra- and hexaaminostilbene sulphonic acid and salts thereof, such as sodium aminotriethoxy succinate (Na6-TCA), as well as alkylbenzene sulphonates. The crystallised or extracted gypsum is dispersed, treated with biocides, sieved and bleached.

EFFECT: high lustre and opacity due to that the gypsum particles are flat and have equal size.

18 cl, 11 dwg, 5 ex

FIELD: chemistry.

SUBSTANCE: mixture is prepared from calcium sulphate semihydrate and/or calcium sulphate anhydrite and water with dry substance content of said mixture ranging from 34 to 84 wt %. The mixture is stirred until formation of a crystalline gypsum product. The reaction mixture can further be mixed with a calcium sulphate dihydrate or a crystal habit modifier selected from ethylene diamine amber acid, amino diamber acid, ethylene diamine tetraacetic acid, diethylene triamine pentaacetic acid, nitrilotriacetic acid, N-bis-(2-(1,2-dicarboxyethoxy)ethylaspartic acid, di-tetra- and hexaaminostilbene sulphonic acid and salts thereof, such as sodium aminotriethoxy succinate (Na6-TCA), as well as akylbenzene sulphonates. Water is used at temperature 0-100°C. Crystallised gypsum is dispersed using a dispersant in amount of 0.01-5.0 wt %, treated with a biocide, sieved and bleached. The obtained gypsum product essentially consists of intact gypsum crystals with size 0.1-2.0 mcm, shape factor 2.0-5.0 and aspect ratio 1.0-10.

EFFECT: simple method.

23 cl, 33 dwg, 28 ex

FIELD: textiles, paper.

SUBSTANCE: composition comprises: a) a filler, b) a cationic inorganic compound - polyaluminumchloride, c) a cationic organic compound, and d) anionic polysaccharide. The filler is present in an amount of at least about 1% by weight, based on the total weight of the composition. Anionic polysaccharide is present in an amount from about 1 to about 100 kg/ton based on the weight of the filler. The composition is substantially free of fibers. Filler composition of the version contains the components a), b), c) and d), as defined above. The only difference is that the component c) is a cationic polyamine condensation polymer, and the component d) has a degree of substitution of stoichiometrically excess anionic groups of up to about 0.65. At that each of b) and c) components present in an amount from about 0 to about 30 kg/ton based on the weight of the filler. At that the composition comprises at least one of b) and c) components. Methods of obtaining compositions of filler comprise mixing a), b), c) and d), as defined above. The invention also relates to a filler composition, which is obtained by this method, an application of the filler composition as an additive to an aqueous suspension of cellulose in the production process of paper and to manufacturing paper comprising adding a filler composition to an aqueous suspension of cellulose. The invention also relates to a paper obtained with this method, and paper comprising the filler composition.

EFFECT: improvement of composition.

35 cl, 1 dwg

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: process engineering.

SUBSTANCE: invention relates to marking of products and goods in various industries. Proposed method consists in application of hidden thread for marking of the product by applying it on the product or its package. Note here that hidden white and hidden black threads are used to be twisted at a time in various combinations with common threads of cotton, flax, silk, synthetic fibers to be sensed by touch.

EFFECT: simple marking, possibility of tactile sensation.

2 cl, 5 dwg

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