Source: https://russianpatents.com/patent/238/2388863.html
Timestamp: 2019-08-24 08:34:12
Document Index: 48713059

Matched Legal Cases: ['art 1', 'art 2', 'art 3', 'art 1', 'art 1', 'art 2', 'art 2', 'art 3', 'art 3', 'art 3', 'arts 1']

Method for production of paper and paper produced by this method
D21H23/02 - characterised by the manner in which substances are added
D21H17/29 - cationic
D21H17/26 - Ethers thereof
The present invention relates to a method for producing a paper product with a high content of filler, which used a paper weight manual process polymers.
In the methods of paper production continues to be interest in finding ways of getting the paper at a lower cost. Because the fillers are cheaper than fibrous mass, one way is to increase the filler content in the paper, and, thus, is able to reduce the amount of pulp in the paper. In addition to economic benefits, the fillers also improve the opacity of the paper and its suitability for printing. However, a significant amount of filler in the paper reduces the strength of the paper. Thus, there is a balance between the possible number of added fillers and desired strength of the resulting paper. Current levels of fillers in the paper differ depending on the grade of paper, for example, the filler content in the paper can be up to 12-14%. The maximum filler content today, considering the available grades of printing paper and fine paper, is about 35%, such as in uncoated magazine paper.
One way to compensate for the reduction in strength caused by the addition of nab is nitela, is to improve the bonding between the fibers in the paper, thus preserving the strength of the paper. With increased paper strength can be increased filler content. Widespread treatment to improve the strength of the paper, in particular paper strength in the dry state, up to this time was the addition of a hardening agent, preferably a cationic starch to the pulp suspension before the operation of the molding sheet. Molecules of cationic starch added to a suspension of pulp may be coupled to the anionic nature of the fiber pulp forces of electrostatic attraction and, thus, be kept in a moist fibrous material and remain in the final paper or cardboard. However, it is difficult to adsorb significant amounts of cationic starch on fiber.
Adding significant amounts of cationic starch in the pulp during paper production to achieve high strength of the resulting paper poses two main problems. The first is that the molecules of cationic starch tend to saturate the anionic charge on the cellulose fibers, thus setting a limit to the number of cationic starch, which can be added to the pulp. If you add an excess of cationic starch, only frequent the added starch is retained in the sheet, and the balance will circulate in the system, purified from the fibrous mass of water, the paper or Board machine. The second problem is that the fibrous mass, which is made cationic by adding excessive amounts of cationic starch, will not be able to adsorb other cationic additives that are usually added to a liquid mass, such as adhesive and substances for increasing uderzhivaemoi filler.
Another way to increase the strength properties of paper is the treatment of the fibers with polymers in successive stages. International application WO 2006041401 describes such a method in which part of the paper pulp is treated with polymers in successive stages through which they receive the paper or paperboard with improved strength and reduced number of polymers.
Another way to increase the strength properties of the paper are described in WO 0032702 where provided the particles (such as fibers or fillers) with a multilayer coating of interacting polymers.
However, there is still a need in a way that could produce paper products that have saved or improved durability at a lower cost.
The purpose of the invention is to offer ways that you can get boom of the hydrated product, having high strength, low cost.
Unexpectedly, it was found that exposing as fillers and fiber pulp polymer processing, as set forth in claim 1 claims, the strength of the resulting paper product significantly improve, even though the content of the filler is high. Thus, the above objective is achieved by the present invention as defined in the attached independent claims. Preferred embodiments of the invention are formulated in the dependent claims and the following description.
The present invention relates to a method for producing a paper product, including the preparation of paper pulp, comprising fillers and fibers; polymer processing paper pulp, in which the polymer is added to the paper pulp at least in three stages; the dewatering of paper pulp on the net obtaining fiber fabric; pressing the specified fiber fabric and drying fibrous webs with obtaining the specified paper product; and the specified paper pulp contains fillers in such quantity that the paper product obtained in this way contains at least 15 wt.%. the fillers. Polymer processing paper pulp, which contains the ox is the Korean people's army and a large amount of fillers, receive a paper product with high strength.
Received a paper product preferably contains 15-70 wt.%. fillers by weight of the total paper.
The polymer used in each of the successive stages of polymer processing, preferably interacts with the polymer used in the subsequent stage. Polymer processing preferably includes one stage, which is added to the cationic polymer, and at least one phase, which is added to the anionic polymer. Alternating the addition of cationic and anionic polymers, believe that you receive the interacting polymer layers. Preferably, the cationic polymer is a cationic starch and anionic polymer, preferably, is a CMC (carboxymethylcellulose). Polymer processing preferably includes from three to seven consecutive stages.
The invention also relates to a paper product obtained by the method according to the present invention.
The invention relates to a method for producing a paper product of paper pulp, comprising fillers and fibrous mass, where the pulp is treated with a polymer, in at least three stages, and the specified paper pulp contains fillers in such quantity that the resulting paper ProductModelID, at least 15% wt. the fillers. The invention also relates to a paper product obtained by the method according to the present invention.
You can obtain paper or cardboard with high amounts of cationic starch and as a result getting a durable product. This is shown in WO 0032702 and WO 2006041401.
Now it was found that the processing of paper pulp, containing as fillers and fibrous mass polymers in three or more stages of polymer processing, the number of fillers in the resulting paper product can be increased, and the strength of the paper is very good, despite the high filler content in the paper. Unexpectedly, it was found that the content of the filler can further increase when the treated paper pulp contains fillers and fibrous mass compared with only processing of pulp or paper fillers weight polymers in successive stages. One theory explaining this, is that when processed according to the invention of paper pulp, containing as fillers and fibers, polymers, particles of filler stronger contact with other particles of the filler or fibrous mass, and the content of the fillers can therefore be increased without adversely affecting the strength of the paper. When printing handling the ke of the entire paper weight polymers in successive stages, and not just one part of the paper pulp, as implemented in WO 2006041401, even more unexpectedly discovered that the strength of the paper is preserved or even increased, even if the filler content in paper is growing.
This method of obtaining a paper or cardboard product includes the preparation of paper pulp, comprising fillers and fibers; polymer processing said paper pulp, in which the polymer is added to the paper pulp at least in three stages; the dewatering of paper pulp on the net obtaining fiber fabric; pressing the specified fiber fabric and drying fibrous webs with obtaining the specified paper product, and the specified paper pulp contains fillers in such quantity that the paper product obtained in this way contains at least 15 wt.%. the fillers. By processing all paper pulp, which includes both the fillers and fibers, it is possible to increase the filler content in the resulting paper product, and the strength of the resulting paper is still unexpectedly is significantly good.
The filler content in paper product is at least 15% wt. from the total mass of a sheet of paper, preferably 15-70% and, more preferably 20-70% or 20-50% by weight, as would what about the detected the strength of paper is still high, even if the filler content is increased, and thus, it gives the opportunity to receive a paper product at a low cost. The content of fillers, more preferably 30-50 wt.%, because the strength of the paper is good even at this high filler contents, it can be seen in the table. The content of the filler is adjusted, to achieve the desired strength of the paper product. It is desirable to have such a high filler content, as far as possible without compromising strength to unsustainable levels. The appropriate amount of fillers depends on the properties of paper pulp and the quality of the paper product. The amount of fillers added to the paper pulp to a paper product with the desired filler content depends on the retention of fillers of fibrous cloth, i.e. how much of the added fillers are retained in the resulting paper product. Retention of fillers varies significantly, and there are many factors that influence it, some examples are the mass of the paper forming device, the paper machine, the fibrous components of the paper pulp, as well as the use and the number of added substances, delapouite uderzhivaemoi filler. Therefore, there is a wide range of what may be holding filler, normally holding the filler is about 20-70%, 20-70% of the added filler is retained in the paper product. Polymer processing paper pulp according to the invention can also influence the retention of filler, however, believe that polymer processing has a positive effect on the retention of fillers. This is due to the fact that as particles of filler and fiber form complexes and that these complexes can improve the ability of the filler to contact the fibers in the paper and, thus, to improve the ability of the filler to remain in the paper.
The polymer used in each of the successive stages of polymer processing, preferably interacts with the polymer used in the subsequent stage, thus allowing a greater amount of polymer to join the fillers and fibers, and thereby leads to increased strength of the final paper product. Polymer processing preferably includes one stage, which is added to the anionic polymer, and at least one phase, which is added to the cationic polymer. Alternating coating of anionic and cationic polymers can be obtained interacting polymer layers.
Used the anionic polymer may constitute one or more polymers, selected from the group consisting of carboxymethyl cellulose (CMC), polyvinyl sulphate, anionic galactoglucomannan, anionic starch, polyphosphoric acid, alginate and poly (methacrylic acid). Preferably, the anionic polymer is a CMC, since it has a high charge density, which reduces the amount of CMC is required for each addition, and, therefore, is economically advantageous. CMC is also very well interact with cationic polymers, and especially with cationic starch. Thus, the use of CMC is very cost effective as a result of its low cost and reduced the required number. Used cationic polymer may constitute one or more polymers selected from the group consisting of cationic starch, polyvinylene, chitosan, primary and secondary amines, polyethyleneimine, polyvinylpyrrolidone and modified polyacrylamides. The cationic polymer preferably is a cationic starch, which is advantageous because it leads to the paper having increased strength properties, and is cost-effective due to their low cost and easy availability. It is preferable to use cationic starch in combination with CMC since the two Danna the polymer, as was found, interact well with each other, giving the paper with good strength at low cost.
Polymer processing preferably includes from three to seven consecutive stages. The optimum number of stages depends on what properties are desired, and depending on the properties of the treated paper pulp. The more stages includes processing, the greater the amount of polymer type and, thus, is kept on paper. Often there is a balance between cost and desired properties, for example, the strength of the paper. Usually there is a limit, when it is not cost effective to add more polymers, as to improve the desired properties such as increased strength or content of the filler is made of paper. It is preferable to add the cationic polymer in the first stage polymer processing, and anionic polymer to add to further and continue alternating the addition of cationic and anionic polymers until the desired number of polymers will not be added in the desired number of steps.
There is no need to wash the pulp between each stages of polymer processing. Any unabsorbed excess polymer added in the previous step may remain in the paper pulp, and it does not need to be washed. It was shown that h is about washing between stages of polymer processing does not improve the properties of the resulting product. Thus, it is advantageous to subject the pulp each stage polymer processing without intermediate rinsing. Because of this, washing between stages of polymer processing is not necessary and can be eliminated, thus, achieves a more rapid process, which, in addition, has a lower power consumption.
After each stage polymer processing should be sufficient time and stirring to the polymer was adsorbiroval on fillers and fiber pulp. Suitable period of time at least 5 seconds between each stage polymer processing. The optimal period of time depends on the performance of mixing equipment.
The polymer in each stage polymer processing can be added to paper pulp in the capacity to the fibrous mass, such as pulp pool, or fluid in the pipeline transport of paper pulp, or combination thereof. The time of addition of the polymer depends on the available equipment and, where practically possible to perform the addition. When exercising three or more stages of polymer processing flow by the addition of the polymer it is necessary to provide a sufficient length of pipe to allow as complete mixing of the polymer, filler and fibrous masses, and to give sufficient time between each stage add DL the adsorption of the polymer. Alternatively, you can use the built-in mixer to ensure good mixing in the pipeline.
The amount of polymer that has to be added varies depending on the properties of paper pulp. When the polymer processing using a cationic starch and CMC, the number of added in each stage of the cationic starch is typically 5-30 kg/t, and the number of CMC added in each stage, typically 0.25-3 kg/so Many polymers must be added to the paper pulp, can be solved by measuring the loading of pulp or process water. Even if the excessive amount of an added polymer is not harmful to the final result, it may be advantageous to add an amount of the polymer, similar to that which can be absorbed pulp mass, in both economic and environmental reasons. However, for some paper products, it was observed that an excess of polymer added to the pulp, leading to improved paper product, i.e. more durable product or product with higher content of filler in retained strength. This can be explained by the fact that the polymers form polyelectrolyte complexes, which can have a favorable effect on the properties of the paper product.
Paper weight tipi is but contains a mixture of different types of pulp, for example, cellulose (pulp hardwood pulp from coniferous wood sulphate pulp or sulfite pulp or wood pulp (chemical-thermo-mechanical wood pulp or thermomechanical wood pulp).
Examples of fillers used in paper pulp, are kaolin, calcium carbonate, precipitated calcium carbonate, talc, gypsum and synthetic fillers.
Manufactured paper products can be any sort of paper any mass, such as bond paper, magazine paper or newsprint.
If necessary, you can use additional well-known stages of paper manufacturing process, such as coating and calendering to obtain a paper product according to claim 1 of the claims.
Ten different samples of paper pulp 1-10 was used to test the method. Used paper pulp was a mixture of wood pulp and Kraft pulp in the ratio of 2.5:1. In six samples only fibrous part of the paper pulp was treated with the polymers, and in the remaining four samples of the polymers were processed all paper weight. As the filler used clay and filler content in the paper product was either 30%or 50%. For comparison some way the s was treated with cationic starch in a single phase, and the other sample was treated with cationic starch and CMC in successive stages according to the invention.
The three stages of polymer processing consisted of:
I. Adding cationic starch to the sample paper pulp;
II. Adding CMC to the sample paper pulp and
III. The addition of cationic starch to the sample paper pulp.
Loading paper pulp was measured after each addition, and the decision on the amount of added polymer in each subsequent stage was taken on the basis of the measurement data. The polymers were added in excess compared to the amount defined based on the dimensions of the load.
In samples 1-6 only fibrous part was subjected to polymer processing and then added fillers, and fibrous mass and fillers mixed in the pulp. Samples 7-10 were subjected to polymer processing completely, i.e. polymer processing were subjected to all the paper mass, including both fiber and fillers.
Then the sheets were prepared by dehydration of paper pulp, pressing and drying a fibrous fabric, and for all of the sheets was determined density (ISO 5270), index strength (ISO 5270) and resistance to delamination (SCAN P 80). Before testing, the leaves kept at 23�C/50% relative humidity. The results are shown in the table.
The table shows the increase in the resistance to delamination and index of the strength of the resulting paper product, when the entire pulp is subjected to polymer processing, compared with the case where processed only fibrous part of the paper pulp. You can also see that the processing of polymers consecutive stages improves as the resistance to delamination, and the index of strength.
Also measured the density, and you can see that in many cases there is an increase in density with increasing amount of starch in the leaf. However, the increase in density is not large enough to explain the increase in the index of strength.
To get a better look at these results, they are also shown in chart 1, chart 2 and chart 3. Reducing the crash., as you can see on the chart, means adding cationic starch in kg/so
The measurement results of the resistance to delamination is shown in figure 1.
Chart 1. The resistance to delamination of the paper sheets 1-10.
Chart 1 shows that the resistance to delamination of the paper sheets is increased when the entire pulp is treated with polymers. The highest value of resistance to delamination can be detected when the pulp is treated with polim the Rami consecutive stages according to the invention. It was unexpectedly found that the resistance to delamination of the paper sheets with a filler content of 50% is very high.
The results of the index strength shown in diagram 2.
Chart 2. The index of strength of paper sheets 1-10.
Chart 2 shows that the index of strength of paper sheets is increased when the entire pulp is treated with polymers. The highest value of the index strength can be detected when the pulp is treated with polymers consecutive stages according to the invention.
Chart 3 shows the index of strength as compared with the amount of starch in the paper sheets.
Chart 3. Index strength as compared with the amount of starch in the paper sheets 1-10.
Chart 3 shows that the index of the strength of the sheets is better for those leaves for which the entire pulp processed polymers, even if the amount of starch in the leaf is not as high. The index of the strength of the sheets with the content of the filler is 50%, when handled all the paper mass is comparable to the leaves with a filler content of 30%, where only the fibrous part of the paper pulp processed polymers.
Therefore, these tests are presented in table, charts 1, 2 and 3 show that is profitable is obrabatyvati all the paper weight, because it gives the paper having high strength, while the content of the filler can be increased.
1. A method of obtaining a paper product, including
the preparation of paper pulp, comprising fillers and fibers;
polymer processing said paper pulp, in which the excess polymer is added to the paper pulp, alternating the addition of cationic and anionic polymers, in at least three stages;
dewatering of paper pulp on the net obtaining fiber fabric;
pressing the specified fiber fabric;
drying fibrous webs with obtaining the specified paper product
moreover, the specified paper pulp contains fillers in such quantity that the paper product obtained in this way contains at least 15 wt.% the fillers.
2. The method according to claim 1, wherein the paper product contains 15-70 wt.% the fillers.
3. The method according to claim 1 or 2, in which the polymers used in each of the successive stages of polymer processing, interact with the polymer used in the subsequent stage.
4. The method according to claim 1 in which the anionic polymer is a carboxymethyl cellulose (CMC).
5. The method according to claim 1, in which the cationic polymer is a cationic starch.
6. The method according to claim 1, wherein processing the polymer includes from three to behold and stages.
7. Paper product obtained by the method according to claim 1.
Improvement of piper and board printing properties and coverability // 2266995
FIELD: improvement of glazed piper and board printing properties and coverability.
SUBSTANCE: claimed method includes addition to fibrous starting material polysaccharide and at least dispersed polymer, containing hydrophobic monomers, as hydrophobic agent. As polysaccharide cationic, non-ionic and/or anionic starch are used. Styrene, butadiene, vinylacetate, acrylonitrile, and/or acrylates, preferably styrene, butadiene, and/or acrylates are used to produce polymer dispersion. Polymer dispersion is obtained by emulsion polymerization. Mixture added to starting fibrous material for paper production contains polysaccharide and at least dispersed polymer, containing hydrophobic monomers, as hydrophobic agent.
EFFECT: paper and board with improved printing characteristics.
28 cl, 1 dwg, 5 tbl, 4 ex
Aqueous compositions of polymer emulsions and their use for paper sizing // 2235819
A method of manufacturing paper for printing // 2213822
The invention relates to the pulp and paper industry, in particular to a method of manufacturing filled with kinds of printing paper, for example, typographic, offset or newsprint
Typical substances and protection elements for control of documents, securities, banknotes, packaging and products // 2200782
Cationic transversally-bound wax-like starch products, method of opbtaining starch products and application in paper products // 2351609
SUBSTANCE: described is product, which has Brookfield viscosity within from approximately 700 to approximately 2500 cps, measured in accordance with method CRA B-54 with 0.5% of hard phase using spindle No 21 at 20 rot/min and temperature 97�C and method of obtaining starch products. Also described is application of cationic transversally bound wax-like starch products, which have Brookfield viscosity within from approximately 700 to approximately 2500 cps, in production of paper products, characterised by productivity 1.9 rolls per hour and inner binding strength 19.5 kPa/cm2.
EFFECT: described is cationic transversally bound wax-like starch product.
32 cl, 14 ex
Composition for cellulose-bearing materials surface treatment (versions) // 2342478
SUBSTANCE: composition concern pulp and paper industry and is intended for cellulose-bearing materials surface treatment. The first composition includes modified carbamide - formaldehyde oligomer and in the capacity of modifier is sodium salt of carboxymethyl cellulose. The second composition contains mentioned above components and melamine. The third composition contains components of the first composition and cationic starch.
EFFECT: improving of composition and strength properties of cellulose-bearing materials.
Cationized polysaccharide product as additive for pulp (versions), method for using the same and method for papermaking // 2310027
FIELD: pulp-and-paper industry, in particular, additive for pulp.
SUBSTANCE: product contains first polysaccharide having at least one first cationic substituent comprising aromatic group, and second polysaccharide having at least one second cationic substituent free of aromatic group. Method for producing of paper from water suspension containing cellulose fibers and, optionally, fillers involves adding cationized polysaccharide product to water suspension; forming and dehydrating water suspension on fabric, said cationized polysaccharide product being produced by providing reaction between first polysaccharide with at least one first aromatic agent, and second polysaccharide with at least one second agent free of aromatic group; mixing resultant polysaccharides.
EFFECT: improved dehydration and retention capacity through utilization of cationized polysaccharide product.
25 cl, 11 tbl, 10 ex
Paper containing ether of cellulose containing quaternary nitrogen // 2347028
SUBSTANCE: paper relates to pulp and paper industry and can be used in the manufacturing sheet and fabric-like products, pressboard and cardboard. Paper contains a filler and ether of cellulose, where ether of cellulose has a quaternary ammonia group, under the condition that, ether of cellulose is not hydroxyethyl cellulose. This also concerns the paper cover, containing ether of cellulose, which has a quaternary ammonia group.
EFFECT: reduction in the time for dehydration for increasing the productivity of paper-making machine, obtaining more high-filled paper for economical efficiency of the process, better filler retention, lowering the accumulation of ether of cellulose in the pulp water, strengthening the paper in a dry state and improving the suitability of the paper to recycling.
Compositions, methods of preparation and application of dispersions // 2223986
The invention relates to compositions and methods for the preparation of dispersions that can be used in particular for ink-jet printing on paper