Composition for manufacture of paper and method for increasing extent of retention and/or dehydration in the same

FIELD: paper making.

SUBSTANCE: composition for manufacture of paper has flocculating cationic polymeric retention means, phenol resin, and polyethylene oxide. Cationic polymeric retention means is liquid aqueous cationic polymer dispersion free of solvent and oil phase and having viscosity of from 2,000 to 20,000 mPa˙s at concentration of 1%. Cationic polymeric retention means may be added into composition in conjunction with phenol resin or separately from it at other point. It may be also used for preliminary treatment of filler which is to be further added to composition.

EFFECT: increased extent of retention and dehydration of composition for manufacture of paper, high quality of paper sheets and reduced manufacture costs.

11 cl, 4 dwg, 5 tbl, 3 ex

 

The scope to which the invention relates.

This invention relates to the manufacture of paper. More specifically, it relates to compositions for making paper, which contains an auxiliary means for holding-based solvent, a cationic polymer in combination with a phenolic resin and polyethylene oxide (PEO) to increase retention and/or dewatering composition.

Background of invention

In the paper production process aqueous suspension of cellulose fibres, possibly containing a filler and a cationic starch, and other chemical agents for the manufacture of paper, put on the wire or fabric, while water is removed with the formation of fibrous canvas or sheet. This aqueous slurry or pulp is called "composition for the manufacture of paper. To efficiently retrieve and increase the speed of the process and reduce the cost of producing paper of high quality is very important to remove water or dehydration of the composition, and retention of small particles, fillers and other chemical agents in the paper sheet.

It is well known the use of a combination of phenolic resin and polyethylene oxide as flocculent to increase retention and dewatering in the process of manufacturing paper and paper cardboard, especially g is senoi paper, when mechanical pulp containing dissolved organic contaminants, harmful effect. In such systems, the phenolic resin is usually added to the first composition to shear using a vane pump, and PEO add a second, usually near the headbox of the paper machine in order to minimize the offset. As is known, the shift is performed at one or several stages of cleaning, mixing and pumping in the papermaking process, this shift leads to the destruction of the remnants of fibers formed Vysokomolekulyarnye polymer, microfiber, which further aglomerados, for example, in the presence of cationic starch.

Assume that the mechanism holding the two-component system of phenolic resin - PEO is, first, adsorption of phenolic resin fibers and small particles and subsequent merger of PEO to the phenolic hydroxyl resin and also to accelerate dehydration. Examples of such two-component systems retention is described, for example, in U.S. patent No. 4070236 and 5472570.

Two-component system of phenolic resin/PEO has the advantage that it is independent from most of the dissolved and colloidal contaminants in the water circuit, as it acts by binding hydrogen atoms. P is Ethiopianist this, cationic polyacrylamides, which is commonly known as an aid to retention, exposed to dissolved and colloidal contaminants that are in mechanical pulp.

In addition, two-component system of phenolic resin/PEO has several other advantages compared to cationic polyamides, including a beneficial effect on the formation of the final sheet and the control resin, which is associated with the system's ability to capture organic contaminants in paper sheet, preventing their deposition on parts of the equipment in the factories, causing possible interruptions.

However, despite these advantages, the retention system of phenolic resin/PEO and dehydration is not used in the factories where made such varieties of paper, as highly special containing wood pulp paper, fine paper (when mechanical pulp from coniferous wood is not a significant part of the composition), tissue and wrapping paper. In these cases, the predominant use of polyacrylamides.

The main reason for the failure using the phenolic resin/PEO in the above cases are the deterioration in the characteristics due to the absence of organic pollutants in the compositions according to the alignment properties of paper, derived from mechanical pulp of softwood, used in the manufacture of many types of newsprint. These pollutants are involved in the mechanism of formation of a mesh structure through which this retention system operates; and their absence in other songs, such as sulfate pulp and recycled, not containing printing inks pulp, has led to the predominance of other systems holding, especially cationic polyacrylamides. In addition, it was found that the presence of residual silicate in the slurry after some operations bleaching and removal of printing ink sometimes has a deleterious effect on the polyethylene oxide, causing loss of retention or dehydration (see Rahman and Tay Tappi Proceedings, 1986, Papermakers Conference, p. 189-198).

Thus, there is a need for improved systems of retention on the basis of phenolic resin/PEO, which will allow to overcome these drawbacks and to increase the degree of retention and the degree of dehydration, especially in such compositions, as sulfide pulp and recycled and purified from the ink pulp.

The purpose and essence of the invention

The purpose of this invention to provide compositions for making paper with a high degree of retention and dehydration on the basis of the systems that hold, containing phenolic resin/PEO.

Another purpose is to provide a method for increasing the degree of retention and dewatering composition for the manufacture of paper while maintaining good quality sheets of paper at a reduced cost.

A further objective is to provide a composition for the manufacture of paper-based systems holding, containing a combination of phenolic resin/PEO, which would be suitable for the production of highly filled containing wood pulp paper, fine paper, tissue and wrapping paper.

Other objectives and advantages of the invention will become apparent from the following description.

Applicants unexpectedly discovered that the auxiliary means for holding consisting of a solvent, a cationic polymer, which is in the form of free oil phase of water-soluble dispersion, in combination with a phenolic resin such as phenol resin, provides a high degree of retention and dewatering, as well as other benefits such as reduced cost when used in conjunction with polyethylene oxide (PEO). When not containing a solvent, a cationic polymer as a means for holding and phenolic resin are added to the composition, they form a structure that provides more efficient reaction with p is litererotica, when it is added to the composition. Retention, namely the retention of fibres, retention of filler and retention of COD (natural resins and other organic contaminants), and dehydration increase to such an extent that such a system is used in the manufacture of fine paper, packaging paper grades and other types of printed products. Achieved an additional increase of the retention of fillers and fine particles, which allows the use of a combination of PEO and phenolic resins or only solvent cationic polymer.

Means for holding solvent cationic polymer suitable for the purposes of this invention, are characterized in that they contain no oil phase. They are liquid, water-solvent-free dispersions of cationic polymers with the usual charge density from 20 to 75 mol%, the solids content is from 2 to 70% and a viscosity of 1%solution in water, equal 2000-20000 MPa·C.

The synthesis of such polymer dispersions are described, for example, in U.S. patent No. 5480934, which also indicates that they can be used as agents for retention in the manufacture of paper, for impregnation of the soil or as a dispersant. However, in this patent there is no assumption that they can be used as a component of the system which we phenolic resin/PEO, providing the above advantages.

Solvent free cationic polymer and a phenolic resin may be introduced into the composition separately in two different points added or together in one point, i.e. they are added sequentially or together, and their combination more favorably interacts with PEO, than if any one component is used. Auxiliary means for holding on the basis of this solvent-free cationic polymer and a phenolic resin can be added to the composition either before or after addition of PEO.

Solvent free cationic polymers suitable for the purposes of this invention, regardless of the number, type or concentration of the monomers used for their production, they can be in the form of liquid or powder. Examples of such polymers manufactures Degussa under the trade names Praestaret To-325 and Praestaret K-350, and Praestol E-125 and Praestor E-150.

Thus, this invention provides a composition for the manufacture of paper, containing a combination of this solvent-free cationic polymer means for holding with phenolic resin and polyethylene oxide as a system for the retention of small particles, fillers and other chemical agents on the sheet of paper.

According to a preferred variant, the number does not contain dissolve Italy auxiliary means for holding is 0.05-10 kg/ton based on the dry weight of the fibers; the amount of phenolic resin is 0.05 to 10 kg of the resin, as it is sold, per ton of dry fibers and the amount of polyethylene oxide is 5-500 g/t based on the weight of dry fibers ("t" means metric tonne).

The preferred ratio of solvent auxiliary means for holding to the phenolic resin is from 200:1 to 1:200, the ratio of phenolic resin to the PEO is from 100:1 to 1:100 and the ratio of solvent auxiliary means for holding to the PEO is from 1:2000 to 2000:1.

The invention also includes a method of increasing retention and dewatering in the composition for the manufacture of paper by adding to the composition an effective amount of solvent cationic polymer funds for retention in combination with phenolic resin and polyethylene oxide. The effective amount depends on the type of dewatering of the pulp and other additives used. It can easily be established empirically by trial and error. The preferred number above.

According to another variant of the present invention, it was found that a further increase in the degree of dehydration of the sheet and the speed of the machine is achieved when the solvent free cationic polymer agent for retention is added after the last BB is Denia PEO and after the last point offset.

According to another variant of the present invention, the filler is pre-treated with solvent free cationic polymer means for holding before it is introduced into the raw material. This pre-processing is a pre-occulation and leads to a better dispersion of the filler in raw materials, a greater degree of retention of small particles/fillers and more opaque. Pre-treated filler is dosed into the raw material to the last point shift and PEO preferably dosed near the headbox, thus, captured particles of the filler, as well as other small particles and fibers in the spatial mesh structure.

Summarizing, we can say that this invention makes use of the synergies between the phenolic resin and not containing a solvent, a cationic polymer means for holding to improve combination with polyethylene oxide and to make possible the use of polyethylene oxide and phenolic resins in various fields and to improve the production of existing newsprint. Further, the synergistic combination of phenolic resin/adjuvant retention, which is not a solvent containing cationic polymer, leads to additional benefits, if not containing the solvent to tionne polymer adjuvant holding pre-mixed with a filler before dosing and reaction with polyethylene oxide.

The implementation of the present invention allows to use the advantages of the introduction of polyethylene oxide in many areas of manufacturing paper than is possible at present. These advantages include a more favorable formation of the leaves than in the case of applying polyacrylamide agent retention, the ability to capture resinous contaminants in the sheet and a lower rate of dosing compared to polyacrylamide systems, resulting in lower steam consumption in the dryer due to the smaller amount of bound water. Other advantages obtained by this invention are the interaction with starch and the ability to provide more effective flocculosa pre-treatment of the filler to the activated filler better dispergirovanija in the feedstock prior to its capture by adding polyethylene oxide. Providing excellent flocculosa pre-treatment of the filler allows the latter to achieve better coverage, while at the same time its "capture" by polyethylene oxide provides good retention of the filler.

Brief description of drawings

Preferred variants of the invention will be described below with reference to the drawings, in which:

figure 1 presents the network device schematic, in which solvent free resin and phenolic resin are administered together in a composition for the manufacture of paper;

figure 2 presents the scheme according to which solvent free resin and phenolic resin is injected separately into the composition for the manufacture of paper;

figure 3 presents the scheme according to which solvent free polymer is added to the composition for the manufacture of paper;

figure 4 is a diagram, according to which the filler is pre-treated with solvent free polymer.

Detailed description of the invention

Below the invention is described with reference to existing drawings, which illustrate some preferred options and in which the same elements have the same numbering.

Thus, figure 1 shows the scheme of the paper manufacturing process, according to which the vane pump 10 is the final point of the shift, after which the song gets to the sieve 12 and from there into the headbox 14. According to this variant does not contain a solvent, the polymer and the phenolic resin is injected into the composition together between the pump 10 and a sieve 12 before the introduction of PEO.

According to the variant shown in figure 2, does not contain a solvent, the polymer is added to the composition to the pump 10 and before the introduction of the phenolic resin and PEO, which is added at the point m is waiting for a pump 10 and a sieve 12. Solvent free polymer is introduced as micropolymer pre-treatment of the fiber.

According to a variant, shown in figure 3, solvent free polymer is added after the last sieve 12 and directly in front of the pressure box 14. It acts as a means for dewatering.

Finally, under option presented on Figure 4, solvent free polymer is introduced together with the filler, which previously handled by this polymer to the pump 10. In this case, the phenolic resin is also introduced to the pump, but after pre-treated filler. PEO add between the pump 10 and a sieve 12.

It should be borne in mind that the above scheme does not in any way limit the invention.

Examples.

For the embodiment of the present invention performed the following laboratory experiments.

For implementation to determine the degree of retention without the formation of the paper stack and test turbidity used the vessel for dehydration Dynamic (DDJ) with guide cylinder, the speed of the stirrer was 500-1000 rpm

To study the retention with the formation of the paper stack, dehydration and study the formation of sheets used analyzer draining Dynamic Drainage Analyzer (DDA). In order to use DDA was the maximum approximation to the conditions of the manufacture of paper. DDA intended the Yong for measuring the speed of dehydration in the formation of the paper stack. In the measurement result holding was higher than when using DDJ, where the foot of paper is formed. Because during the experiment, the stop is formed of paper, can also be achieved by forming a wet sheet.

The dehydration.

The degree of dehydration in DDA was estimated as the time interval from the start of the experiment before the start of the suction of air through the sheet, and it is automatically recorded by the computer within one hundredth of a second. Dehydration is influenced by many factors, such as grammage, the magnitude of the vacuum, the volume of sample, type of substrate, temperature, wire braid and chemical agents. Usually it is desirable to apply the same consistency of the composition, as in the factory. However, for compositions with high fluidity and rapid dehydration can increase the accuracy of the experience, if you use a higher content of solids or greater sample volume.

Hold.

Retention is measured as the number of fibers retained on the wire braid in comparison with the number of fibers that pass through it. The degree of retention during the experiments in DDA higher than bumagodelatelnoe car. However, it is very well correlated with the values obtained in the vessel Britt. The invention is illustrated by the following examples, not limiting, however, the scope of the invention.

Example 1.

<> 1,06% suspension of cellulose fibers consisting of 50% TSR (thermo-mechanical pulp, bleached hydrosulfite), 20% DIP (pulp, not containing printing inks) and 30% of waste was received at the factory newsprint. The slurry contained 20% of the filler is clay. the pH of the suspension was brought to 4.5.

To determine the degree of retention and coverage used the vessel for dehydration (DDJ) with guide cylinder, the speed of the stirrer was equal to 550 rpm To determine the used sample volume of 500 ml. FPR means holding the first pass.

To determine dehydration, structure and retention (with the formation of the paper stack) used the analyzer dehydration (DDA) with the guide cylinder, the speed of the stirrer was increased to 1000 rpm To determine the used sample volume of 800 ml, the Amount of vacuum was set to 500 mbar.

Below in Tables 1 and 2 shows the results of comparison of conventional systems holding phenol-formaldehyde resin - polyethylene oxide system phenol-formaldehyde resin - polyethylene oxide - containing solvent, a cationic polymer occulant. In tables turbidity values are given in units of turbidity (NTU).

Example 2.

0,992% suspension of pulp fibers comprising 10% of Kraft pulp and 90% of TM is (thermomechanical pulp, bleached hydrosulfite), received at the factory special newsprint. The suspension contained 10% of the filler is clay. the pH of the suspension was set equal to 6.0.

To determine the degree of dehydration, formation and retention (with the formation of the foot) used the experience with the use of the analyzer dehydration (DDA) with the guide cylinder, the speed of the stirrer was increased to 1000 rpm For tests took a sample volume of 800 ml Vacuum was equal to 500 mbar.

Table 3 below shows the results of comparison of conventional systems holding phenol-formaldehyde resin - polyethylene oxide system phenol-formaldehyde resin - polyethylene oxide - containing solvent, a cationic polymer occulant.

Example 3.

1,12% suspension of cellulose fibers, containing 5% pulp Kraft, 70% of TMP (thermomechanical pulp, bleached hydrosulfite) and 25% pulp, not containing printing ink (DIP), received at the factory special newsprint, using recycled fiber. The content of clay filler was 30%. the pH of the suspension was set equal to 6.2.

To determine the degree of retention and turbidity used the vessel for dehydration (DDJ) with guide cylinder. The speed of the stirrer was 550 rpm For experience used the image of the C volume of 500 ml. FPR means holding the first pass, FPAR - holding ash on the first pass.

Table 4 below shows the results of comparison of conventional systems holding phenol-formaldehyde resin - polyethylene oxide system phenol-formaldehyde resin - polyethylene oxide - containing solvent, a cationic polymer occulant.

Table 4.
Experience with the use of DDJ.
Product nameThe dose of product (g/t)Product nameThe dose of product (g/t)Product nameThe dose of product (g/t)FPR/FPAR (%)Turbidity (NTU)Normaliz. value (0-100)
-0000035,6/45,486,10
Solvent free polymer occulant was added to the phenolic resin and PEO
Not containing. solvent cationic polymer300Phenolic resin420The polyethylene oxide6048,0/68,236,2of 97.8
Solvent free poly is Erny the occulant was introduced after phenol resin and PEO
Phenolic resin420The polyethylene oxide60Not containing. solvent cationic polymer30042,2/56,634,1of 97.8
Solvent free polymer occulant was introduced after the phenolic resin before and PEO
Phenolic resin420Not containing. will dissolve. the cation. polymer300The polyethylene oxide6046,4/57,836,2of 97.8
Only phenolic resin and PEO
Not containing. solvent cationic polymer0Phenolic resin0

420

700
The polyethylene oxide60

60

100
37,1/47,8

42,9/64,8

41,3/43,3
35,7

40,7

42,6
26,2

60,1

100,0
Only solvent free polymer flocculant
Not containing. solvent cationic polymer300Phenolic resin0The polyethylene oxide041,1/43,336,2of 37.8

Were also tested on a machine that is e factory. Solvent free cationic occulant was added before the introduction of the phenolic resin and PEO (viscous material). The table below shows the results of comparison of conventional systems holding phenol-formaldehyde resin - polyethylene oxide system phenol-formaldehyde resin - polyethylene oxide - containing solvent, a cationic polymer occulant.

All relevant machine parameters and the number of polymer are shown in Table 5.

td align="center"> 560
Table 5.
The machine parameters before and after adding the solvent-cationic polymeric retention tools.
Without solvent free cationic polymer means holdingIn the presence of this solvent-free cationic polymer means holding
Grade643,01643,01
Grammage (mass 1 m2paper) (g/m2)4141
Speed(m/min)813855
% pulp without ink (DIP)00
% bleached pulp softwood kraft (SBK)25,225
Press the s pair in the 1st section (kPa) 114100
The vapor pressure in the 2nd section (kPa)177210
The pressure of steam in the 3rd section (kPa)273258
The concentration of pulp in the pressure box (%)1,1541,02
The concentration of white paper (%)China 0,6860,537
Retention at the first transition (%)40,6647,1
The ash content in the pressure box (%)14,878,43
The ash content of the white paper (%)21,113,23
Holding the ashes at the first transition (%)12,317,44
% ash content in the sheet32,3
% clay Alphatex, added to the headbox2,011,89
Consumption of cationic agent (IU/l)286213
Turbidity in the pressure box (NTU)12143
The opacity of the white paper (NTU)9032
The amount of this solvent-free cationic polymer (g/t)0300
The amount of phenolic resin (g/t)235
The amount of coagulant (g/t)2100
The number of polyethylene oxide (g/t)5938
Cost reduction (%)--12,60%

The cost of 12.6% is a significant advantage of the process of making paper.

The above results clearly show that the combination of this solvent-free cationic polymer is a phenolic resin - PEO is the best system for economic reasons. The retention system utilizing a combination of phenolic resin/PEO in combination with solvent free cationic polymer, allow to obtain the highest degree of retention of fine particles using the DDJ and DDA, the lowest turbidity and the high speed dehydration, which is proof of the ability of these systems to retain fine particles and colloidal substances.

This is especially true in the case of the following sequence of adding the components: solvent free cationic polymer /phenolic resin/ polyethylene oxide. In contrast, solvent free cationic polymer or system of phenolic resin/polyethylene oxide used in isolation, lead to a lower degree the Yeni retention and/or higher turbidity.

Based on these results we can conclude that there is not only a synergism between the phenolic resin/PEO and does not contain a solvent, a cationic polymer, but also a significant reduction in costs.

It should be noted that the specific described above options and examples do not limit the scope of the invention, the experts obviously, it is possible to make various modifications to this invention, without leaving the scope of the invention, the scope of which is defined by the claims.

1. Composition for the manufacture of paper, containing a combination of flocculonodular solvent free cationic polymer means for holding with phenolic resin and polyethylene oxide as a system for the retention of small particles, fibers and other chemical agents for the manufacture of paper in a paper sheet, characterized in that flocculosa not containing a solvent, a cationic polymer, the means for holding is a liquid aqueous, solvent free dispersion of cationic polymer, not/containing oil phase and having a viscosity at a concentration of 1%, from 2000 to 20 000 MPa·C.

2. Composition for the manufacture of paper according to claim 1, characterized in that the cationic dispersion polymer is characterized by a charge density from 20 to 75 mol.% and solids content of the 2 to 70 wt.%.

3. Composition for the manufacture of paper according to claim 1, characterized in that the amount of this solvent-free cationic means for holding is 0.05-10 kg/t based on the weight of dry fibers, the amount of phenolic resin is 0.05-10 kg/t of dry fiber and the amount of polyethylene oxide is 5-500 g/t based on the weight of dry fibers.

4. Composition for the manufacture of paper according to any one of claims 1 to 3, characterized in that the ratio of solvent free cationic means for holding to the phenolic resin is from 200:1 to 1:200, the ratio of phenolic resin to the polyethylene oxide is from 100:1 to 1:100 and the ratio of solvent free cationic polymer means for holding the polyethylene oxide is from 1:2000 to 2000:1.

5. Method of increasing retention and/or dewatering in the composition for the manufacture of paper by adding to the composition an effective amount of a liquid water-containing solvent, a cationic polymer flocculonodular means for retention of viscosity in water at a concentration of 1% from 2000 to 20000 MPa·in combination with phenolic resin and polyethylene oxide.

6. The method according to claim 5, characterized in that the solvent free cationic polymer means for holding added to the composition together with a phenolic resin in the same is the point.

7. The method according to claim 5, characterized in that the solvent free cationic polymer means for holding added to the composition separately from the phenolic resin at a different point.

8. The method according to subparagraph 5, 6 or 7, characterized in that the solvent free cationic polymer means for holding and phenolic resin is added to the composition before or after the introduction of polyethylene oxide.

9. The method according to claim 7, characterized in that the solvent free cationic polymer means for holding added last, after the phenolic resin and polyethylene oxide, and after the last point offset.

10. The method according to claim 5, characterized in that it comprises adding a filler to the composition and pre-treatment of the filler does not contain a solvent, a cationic polymer means for holding.

11. The method according to claim 10, characterized in that the pre-treated filler is metered into the composition until the last point shift and before the addition of polyethylene oxide.



 

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EFFECT: polymer dispersion of high stability, high active substance content, low cationic charge, and good retention characteristics.

FIELD: paper industry.

SUBSTANCE: aqueous composition includes 0.01 to 45 % by weight of anionic organic polymeric particles and silica-based colloidal anionic particles at weight ratio between them from 20:1 to 1:50. Silica-based colloidal anionic particles are prepared by modifying silica with aluminum or amine. Anionic organic polymeric particles are prepared by polymerization of ethylenically-unsaturated monomers with multifunctional ramification agents and/or multifunctional cross-linking agents. Composition is prepared by combining the two types of particles. Papermaking method comprises adding above-prepared composition to pulp composed of cationic polymer fibers.

EFFECT: imp drying and retention properties of aqueous composition.

16 cl, 4 tbl, 4 ex

FIELD: polymer materials and papermaking industry.

SUBSTANCE: invention relates to aqueous silicon-containing composition containing anionic organic polymer comprising at least one aromatic group and silica-based anionic particles in aggregated form or microgel form. Anionic organic polymer, in particular, contains at least one aromatic group and silica-based anionic particles in amount at least 0.01% of the total mass of composition. Composition contains essentially no sizing substance capable of reacting with cellulose, whereas anionic organic polymer containing at least one aromatic group is not naphthalenesulfonate-formaldehyde condensate. Invention also relates to methods for preparing the composition and to utilization thereof as a substance providing dehydration and retention in paper making process. Invention further relates to a paper making process using aqueous suspension containing cellulose fibers and optionally filler, wherein aqueous silicon-containing composition and at least one charged organic polymer are added to pulp.

EFFECT: improved dehydration and/or retention in paper making process and increased storage stability.

20 cl, 4 tbl, 4 ex

FIELD: pulp-and-paper industry, in particular, sizing of paper with the use of aqueous composition.

SUBSTANCE: method involves producing aqueous composition of cellulose filaments and dehydrating paper web; adding aqueous composition to cellulose suspension, said aqueous composition comprising sizing substance aggregates; producing aqueous composition by mixing in any order before adding into aqueous suspension of aqueous solution containing at least one coagulant and aqueous dispersion containing sizing substance. Zeta-potential of composition is below 20 mV.

EFFECT: increased efficiency and simplified method.

26 cl, 5 tbl, 3 ex

FIELD: paper-and-pulp industry.

SUBSTANCE: process of manufacturing cellulose products such as paper articles is accomplished by simultaneously or continuously adding at least one aluminum compound and at least one water-soluble silicate, in particular at least one product of reaction of monovalent cation silicate with bivalent metal ions, to fluid cellulose pulp such as paper pulp. Compositions are also described comprising at least one aluminum compound and at least one water-soluble metal silicate and cellulose products including at least one water-soluble metal silicate complex.

EFFECT: improved retention and drainage allowing manufacture of high-quality cellulose products.

25 cl, 6 tbl, 27 ex

FIELD: inorganic chemistry.

SUBSTANCE: invention relates to composition containing water-soluble silicate complex of general formula (1-y)M2O*yM'O*xSiO2, wherein M is monovalent cation; M' - bivalent cation; x = 2-4; y = 0.005-0.4; y = 0.001-0.25. Method for production of said composition includes mixing of silicates with monovalent and bivalent cations.

EFFECT: composition useful in production of cellulose sheet.

23 cl, 17 ex, 18 tbl

FIELD: inorganic chemistry.

SUBSTANCE: invention relates to composition containing water-soluble silicate complex of general formula (1-y)M2O*yM'O*xSiO2, wherein M is monovalent cation; M' - bivalent cation; x = 2-4; y = 0.005-0.4; y = 0.001-0.25. Method for production of said composition includes mixing of silicates with monovalent and bivalent cations.

EFFECT: composition useful in production of cellulose sheet.

23 cl, 17 ex, 18 tbl

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