Method of paper or cardboard production and paper or cardboard produced by method
FIELD: textile, paper.
SUBSTANCE: method relates to paper or cardboard production and can be used on pulp-and-paper industry. Part of paper pulp fiber is treated with a polymer at least within two stages. Paper pulp treated with the polymer is mixed with remaining non-treated paper pulp. The mixed paper pulp is dehydrated on a net conveyor for forming fibrous web.
EFFECT: increase of strength without negative effect upon paper or cardboard volume with decreasing quantity of adding polymers and enhancing economical efficiency of the process.
14 cl, 4 dwg, 2 ex
The present invention relates to a method for manufacturing paper or cardboard products, which used a paper weight handle partially-Paladino polymers.
Prerequisites to the creation of inventions
In the paper industry there is a need for durable paper and cardboard products with high volume (low density). For the manufacture of paper and cardboard products, with high volume, less amount of fiber, which is especially desirable for economic reasons. Bulk cardboard products with low fiber content has a greater stiffness in bending. Paper and cardboard products are usually produced by dehydration of the composition on a grid conveyor. The composition often contains a mixture of different pulp mass, including both pulp and mechanical wood pulp. For making larger paintings with greater structural rigidity began to use more mechanical wood pulp high degree of grinding. For best results mechanical wood pulp must contain long undamaged fiber and less small particles of fiber. However, the pulp containing a large number of coarse long fibers, unfortunately, have low when osobnosti to the formation of a sufficient bonding of the fibers in paper or cardboard. The dimensions and mechanical properties of the resulting paper or paperboard, thus, are a compromise between the ability of the pulp to increase volume and its ability to enhance skleivaemosti fibers of paper or cardboard.
Sleevenote fibers mechanical wood pulp can also be enhanced through its processing of chemical additives. The prevailing processing to enhance strength, especially the strength in the dry state, of paper or paperboard hitherto consisted in the addition of cationic starch in the slurry of cellulosic fibrous mass to the operation of the sheet formation. However, it is difficult to ensure the adsorption of large quantities of starch and fiber, especially when a small quantity of small particles of fiber. Molecules of cationic starch added to a suspension of pulp may stick to the fibres of natural anionic pulp under the influence of electrostatic attraction and thus maintained in a wet fibrous web and to remain in the finished paper or paperboard.
However, there are two main drawbacks when using nationaldirectory starch as an additive in the suspension of pulp for making paper. The first drawback lies in the fact that the molecules of the cationic starch can hearth shall be anionic charge on cellulosic fibers, thus setting a limit to the number of cationic starch, which can be added to the suspension. If you add an excessive amount of cationic starch, only a part of added starch will be held in the canvas, and the rest will circulate in the circulating water system of the paper or Board machine. The second disadvantage is that the fibers become positively charged under the influence of added excess amount of cationic starch, cannot adsorb other cationic additives, which are usually injected into a suspension of pulp, for example, adhesive agents.
Another way to improve the strength properties of the paper lies in the treatment of fibers with polymers. This method is described in international patent WO 0032702 A1, according to which particles, such as fibers, provide a multilayer coating of interacting polymers. Particles treated in the course of sequentially executing the stages of the solutions of the interacting polymers. Before each subsequent stage of processing of unabsorbed excess polymer previous stage must be removed if not exercised by careful regulation of the amount added in each stage of the polymer, so that essentially all of the polymer was absorbed on the surface of the particles is in order not to leave too much.
By treating the pulp according to the method described in international patent WO 0032702 A1, paper introduce more polymers and ensure their retention in it. Paper made from the treated pulp, has increased strength. However, it is established that polymer processing according to this method has a negative impact on the volume of paper, i.e. paper weight becomes undesirable high. Polymer processing is the process by which consume substantial amounts of polymer. Thus, there is a need for a method of manufacturing paper or cardboard, through which you can increase strength without negative effects on the volume.
Brief description of the invention
The aim of the invention is to provide a method for manufacturing paper or cardboard, which would have increased strength without detrimental effects on their volume.
To reach this aim by using the method according to claim 1 of the claims. It was also established that if the subject polymer processing only part of the paper pulp, the strength of the resulting paper or paperboard products is significantly increased, while the volume remains essentially unaffected. Above, the purpose of such education is, reach through the use of the present invention, as defined in additional independent claims. The preferred options are presented in the dependent claims and the subsequent description.
The present invention created a method of manufacturing paper or cardboard products, including: providing paper pulp containing fibers; polymer processing the first part (1) paper pulp, which pulp type polymers, in at least two stages; mixing the aforementioned polymer subjected to the processing of the first part (1) paper pulp raw second part (2) paper and pulp dewatering of paper pulp on a grid conveyor for forming a fibrous web. By processing only part of the paper pulp strength of the resulting paper or paperboard products significantly increase, leaving the volume essentially unaffected.
Mentioned the first part of the paper pulp preferably contains 20-80 wt.% of the total weight of the composition. In one embodiment, referred to the first part of the paper pulp containing the long fibers present in the composition. Polymer processing is preferably performed using the first part of the paper pulp, which contains sulfate is or sulfite pulp mass of the fiber is soft (pine) wood. Paper pulp can contain fillers and other additives used in the manufacture of paper, with the fillers and additives can be added after the polymer processing mentioned the first part of the paper pulp. In an alternative embodiment, the fillers and additives can instead be added to the polymer processing mentioned the first part of the paper pulp.
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. According to one theory by alternating cationic and anionic polymer additives get interacting polymer layers. The cationic polymer is preferably cationic starch and anionic polymer is preferably carboxymethylcellulose (CMC). Polymer processing can be performed in two to seven stages. Polymer processing is preferably carried out in three to seven consecutive stages.
The invention also relates to a paper or cardboard product, manufactured according to the method in accordance with the present invention.
Brief description of drawingsFigure 1 presents a schematic view of one of the variants of the method according to the present invention;
figure 2 - comparison chart of density and strength of the paper produced according to the present invention and manufactured according to the method prototype.
Detailed description of the invention
The invention relates to a method of making paper or paperboard of paper pulp, part of which is treated with a polymer, in at least two stages. The invention also relates to a paper or cardboard product, manufactured according to the method in accordance with the present invention.
When processing paper pulp according to the method prototype, described in document WO 0032702, during which the whole composition is treated with cationic and anionic polymers performed sequentially in stages, the number of polymers in paper or cardboard products may be increased. Thus, for example, in manufacturing paper or cardboard with a high content of cationic starch and, therefore, to get a very strong paper or cardboard products.
It is now established that by processing the polymers only part of the pulp during two or more stages of polymer processing, the amount of polymer added to the composition, decreases in the calculation of the and the whole mass of cellulose composition, and strength properties of paper or paperboard unexpectedly remain very good, despite the reduction in the amount of added polymer. Even more unexpectedly, the volume of paper or cardboard products only increases slightly in comparison with a paper or cardboard products, which were not added to the polymers. The smallest increase in density, it is important to obtain cardboard with high rigidity in bending at a certain strength.
The present method of manufacturing paper or cardboard product includes: providing paper pulp containing fibers; polymer processing the first part (1) paper pulp, in which the composition is added to the polymer in at least two stages; mixing the aforementioned polymer subjected to the processing of the first part (1) paper pulp raw second part (2) paper and pulp dewatering of paper pulp on a grid conveyor for forming a fibrous web. By processing only part of the pulp strength of the resulting paper or paperboard products thus unexpectedly significantly increased, while the volume remains essentially unaffected. Mentioned the first part of the paper pulp contains 20-80 wt.% of the total weight of the composition, preferably 20-50 wt.% of the total who assy composition. Share the first part of the regulate to achieve the desired strength and density of the products, while providing for the possibility of a small amount of added polymer. If the first part is too small, then increasing the strength of the products is not sufficient, as part of paper pulp, processed polymers, mixed with mostly raw paper pulp. On the other hand, if the first part is too large, then the required increase of the added amount of polymer is <on> greater than can be achieved increasing the strength of the product, this also increases the density of the product (i.e. decreases its volume). The corresponding proportion of the first part also depends on the properties of the composition of the first part, as well as from the properties of the second part. Paper pulp usually contains a mixture of various types of pulp, such as wood pulp (pulp solid (hardwood) wood, soft (pine) wood, sulphate or sulphite pulp or mechanical pulp (chemical thermo mechanical pulp (TMDM) or thermomechanical pulp (TMDM)). In one embodiment, the mentioned first part composition containing the long fibers present in the composition. These fibers attach great coloring strength is ü finished products, the more short fibers, and polymer processing, therefore, is especially effective when doing it using part of the composition containing the long fibers. Polymer processing is preferably performed by using the first part of the composition containing sulphate or sulphite pulp, as these pulp contain long fibers in comparison with other pulp mass. Processing part of the composition containing sulphate or sulphite pulp is thus normal by selecting the part containing long fibres, ready-mixed composition. However, the above-mentioned first part of the song, which is subjected to polymer processing, can contain any part of the song. The composition may also contain fillers and other additives used in the manufacture of paper; fillers and additives can be added after the polymer processing mentioned the first part of the composition. In an alternative embodiment, the fillers and additives can instead be added to the polymer processing mentioned the first part of the composition. A certain amount of paper and cardboard contains fillers or other additives, by means of which improve the surface properties of paper. However, particles of the filler are also harmful in the iyayut strength of paper. One theory is that when processing polymer compositions containing fillers and additives according to the invention, the particles of filler and additives stronger stick to other particles or fibers and, therefore, a high content of filler to some extent, does not have a detrimental effect on the strength of paper.
The polymer used in each of the successive stages of polymer processing, is preferably interacts with the polymer used in the subsequent stage; thus allowing the possibility to attach to the fibers more polymers and thus in the increase of the strength of the finished paper or paperboard products. Polymer processing preferably includes one stage, during which adds anionic polymer, and at least one stage, during which the type of cationic polymer. By alternating anionic and cationic polymeric coatings can be obtained interacting polymer layers.
The anionic polymer may be one or more selected from the group consisting of: carboxymethylcellulose (CMC), polyvinyl sulphate, anionic galactoglucomannan, anionic starch, polyphosphoric acid, alginate and poly (methacrylic acid). Anionic polymer is prefer is Ino CMC, as she interacts well with cationic polymers, and its use is economically advantageous because of its low cost. The cationic polymer may be one or more selected from the group consisting of: cationic starch, polyvinylene, chitosan, primary and secondary amines, polyethyleneimine, polyvinylpyrrolidone and modified polyacrylamides. The cationic polymer is preferably cationic starch, which is preferred, as a result of its use are cardboard or paper having improved strength properties, and because it is economically advantageous due to its low cost and easy availability.
Polymer processing is preferably performed in two to seven consecutive stages. The optimal number of stages depends on the required properties of paper or cardboard, and from the properties of the composition subjected to processing. The larger the number of stages includes processing, the greater the amount of polymer type and, thus, more of them kept in paper or cardboard. Often there is a balance between cost and desired properties, such as strength of paper or cardboard. Usually there is a limit beyond which it is inadvisable from the point of view of economic efficiency, add polymers to further improve desire what's properties, for example, increasing the strength of the produced paper or cardboard. Preferably the addition of the cationic polymer in the first stage polymer processing and adding anionic polymer during subsequent processing, as well as the continuation of the alternate adding the cationic and anionic polymers to achieve the desired amount of polymer added in the course of performing the desired number of stages.
The composition need not be washed between stages of polymer processing. Any unabsorbed excess amount of polymer added in the previous stage, may remain in the composition and does not need to be washed. Tests have shown that washing between stages of polymer processing does not result in improved properties of the resulting products. Thus, it is preferable to expose the first part of the song each stage polymer processing without any intermediate rinsing. Thus, an optional stage can be excluded, due to what can be expedited processing, requires less water.
After each stage polymer processing should be enough time for mixing of the polymer, which must be absorbed by the fibers of the first part of the composition. Suitable period of time between each stages of polymer processing and is at least 5 seconds. The optimal period of time depends on the performance of the hardware mixing.
The polymer in each stage polymer processing can be added to the composition that is in the tank for pulp, for example in pulp pool, or in production lines in the pipeline for the transportation of pulp, or combination. The place that's supposed to add the polymer depends on the available equipment and the feasibility of the introduction. If two or more stages of polymer processing by introducing the polymer into a production line must be provided for a condition where either the pipe must be of sufficient length in order to thoroughly mix the polymer and the pulp mass and enough time between stages of introduction of the polymer, which is supposed to absorb or production line, you can use the mixer to ensure good mixing in the pipeline.
The amount of polymer to be added can vary depending on the properties of the pulp. When using cationic starch and CMC for polymer processing, the amount of cationic starch added in each stage, is typically in the range 5-25 kg/t, and the number of CMC added in each stage, usually costs the t in the range of 0.25-3 kg/T. The amount of polymer added to the composition can be monitored by measuring the z-potential or measurement nationaliste pulp. Even if the excessive amount of an added polymer is not harmful to the finished product, then, of course, it is preferable to add such an amount of polymer, which is close to the amount that can be absorbed by the pulp mass, both for economic reasons and for reasons connected with the protection of the environment.
Figure 1 schematically illustrates the method according to one embodiment of the invention. This embodiment of the composition for the manufacture of paper or paperboard served in the tank 1, 2 for pulp, respectively. The composition is submitted and contained in the first container 1 for pulp, designated as the first part of the composition, and the composition is submitted and contained in the second vessel 2 for pulp, designated as the second part of the composition.
The first part of the composition is subjected to polymer processing in three stages. The second part of the composition is not subjected to any polymer processing. In the first stage 4 polymer processing cationic polymer such as cationic starch, add in the first part of the composition in the production line in a pipeline for transporting the composition, which is you the e flow from the tank 1 to pulp. In the second stage 5 of anionic polymer added to the composition in the first container 1 for pulp. The second stage 5 of the polymer processing start for at least 5 seconds after adding the first polymer. Capacity for pulp equipped with a stirrer, which provide a sufficient degree of mixing of the composition with the added polymer. The composition is directed from the tank 1 to the pulp in the headbox 3. The third stage polymer processing is carried out by adding 6 cationic polymer (e.g., cationic starch) in a flow line through which is in flow-line mixer 7 in the pipeline for the transportation of the composition, and referred to the mixer in the production line is located downstream from the pipeline to transport, but upstream from the headbox. After the third stage polymer processing the first part of the composition, the treated polymer is mixed with the second part of the composition, which is supplied from the vessel 2 for pulp, at a point between valve and pressure box. The composition is then sent from the headbox on a grid conveyor, where it is dewatered and further treated by a method known in this field of production, for the manufacture of paper or cardboard.
A variant is illustrated in figure 1, can is also used for the manufacture of multilayered paper or paperboard, in which only part of the composition for making the middle layer is treated with polymers, whereas the lower and upper layers of paper or paperboard consist of paper pulp, which is not processed.
For the evaluation method used twelve different samples 1-12 compositions. Six samples were partially or completely subjected to three-stage polymer processing. For comparison, the six equivalent samples were left in an unprocessed state. Samples of the compositions contained HTMLM mixed with different amounts of unbleached sulphate pulp of soft wood.
The three stages of polymer processing consisted of the following:
I. adding cationic starch in the sample composition;
II. the addition of CMC in the sample composition;
III. the addition of cationic starch in the sample composition.
After each stage polymer treatment was followed by rinsing. In the polymer processing, thus, received a composition containing two additions of cationic starch and intermediate additive of the CMC.
Samples 2, 4 and 6 were subjected to polymer processing entirely. Samples 8, 10 and 12 were divided into the first part, which contained only sulphate cellulose, and the second part, which contained only TMDM. The first part of each sample is (sulphate pulp) was subjected to polymer processing, while the second part of each sample (TMDM) was left untreated. The first and second parts are then mixed with one another. Samples 1, 3, 5, 1, 9 and 11 are not subjected to any polymer processing.
Then were prepared canvases by dehydration of the composition, determined density (density STFI) and strength values Scott-Bond of all paintings. A measure of the strength of Scott-Bond is a measure of the strength in the direction of the z-axis of the canvas. The results are presented in the table and the chart in figure 2.
|Sample||Designation chart 1||Chemi-thermomechanical pulp (TMDM), wt.%*||Sulphate pulp, wt.%*||The proportion of fiber from the total mass to be subjected to polymer processing, wt.%*||STFI density, kg/m3||A measure of the strength of Scott-Bond, j/m2||Increasing the density of the polymer after processing, %||The increase in strength of the Scott-Bond polymer after processing, %|
|8||Δ||80||20||20 (only a portion||570||280||3,5||45|
|10||●||70||30||30 (only a portion of sulphate pulp)||590||295||4,2||51|
|12||□||60||40||40 (only a portion of sulphate pulp)||625||430||4,8||59|
|* the percentage of the total fiber content|
|** the percentage of the total fiber content|
The table shows the increase (in percent) indicator of the strength of the Scott-Bond and the density of the sample subjected to three-stage polymer processing, in comparison with the untreated sample. When processing polymers of the composition consisting of 20% cellulose 80% TMDM, as it was made with the sample 4, the density increased by 14%, and the measure of the strength of Scott-Bond increased by 58%. When processing polymers only sulfate of the composition (20%), as it was made with the sample 8, the density increased by only 3.5%strength by 45%. Therefore, even if only 20% of the composition was processed polymers, a measure of the strength of Scott-Bond was increased by 45% compared to 58% when treatment is ode of the entire composition, as the volume increased only by 3.5% compared with 14%.
Figure 2 presents the diagram of the indicators of the strength of Scott-Bond cloths made from samples of the compositions. In the diagram the line drawn between the values for each raw sample and its corresponding equivalent sample subjected to polymer processing. Solid lines on the diagram labeled samples in which the composition was subjected to polymer processing. Dotted lines indicate samples in which only the sulfate portion of the composition was subjected to polymer processing. A steeper slope indicates a greater increase in strength with a smaller increase in density.
As shown in figure 2, the dashed line is more steeply inclined than the solid line. Polymer processing only sulfate of the composition leads thus to a significant increase in strength, but the density remains almost constant. As shown in solid lines, when the polymer processing of the entire composition observed a greater increase in strength than after partial processing, however, the density of paintings, molded from the fully processed composition is also increased to a greater extent than is observed after partial processing.
The results observed in paintings formed the C samples 8, 10 and 12, which were subjected to polymer processing according to the invention, therefore, show that unexpectedly high strength while maintaining a low volume obtained when a small amount of polymers.
Manufactured cardboard, consisting of three layers. The composition from which were formed the top and bottom layers of cardboard, consisted of 50% pulp from solid (hardwood) wood and 50% pulp from soft (pine) wood, the number of SR (SR - degree of grinding) was approximately 27.
The composition from which was formed the middle layer of cardboard, consisted of 55% HTMLM and 45% of the mixture, which is below named part mixed, and the mixed part consisted of approximately 55% bleached pulp from soft (pine) wood, 15% bleached pulp from solid (hardwood) wood and 30% TMDM. Cardboard, the middle layer which consisted of TMDM and the above-mentioned mixed part, is a typical cardboard, which is made containers for liquids.
Have produced five different samples of cardboard. In two of the samples of the whole composition, which is used to make the middle layer, processed polymers during three successive stages (two stages with the addition of cationic starch and one intermediate stage to add the group COMC). The other two samples were processed according to the invention, i.e. only the mixed part of the composition (45% of the entire composition) were treated with polymers during three successive stages, and processed mixed part then mixed with the raw part TMDM. One sample was used as reference, which was not subjected to polymer processing.
The amount of polymer, which was added in each stage was determined by measuring the z-potential. First I added a small amount of cationic starch and constantly measured z-potential; when the value of the z-potential is stabilized, it is meant that the quantity added is appropriate. Then the same method was added anionic COMC, and when the value of the z-potential was close to zero, it meant that the added amount is appropriate. The amount of polymer added in the next stage, was determined in the same way. Between additions of polymers did not do a rinse composition.
The amount of polymer added to the composition during processing of the composition during three successive stages, as follows: 15 kg/t of cationic starch in the first stage; 1.5 kg/t CMC in the second stage and 10, respectively 15 kg/t of cationic starch in the third stage.
When processing only the mixed part of the composition during the three follower who's stages added: 15 kg/t of cationic starch - in the first stage; 1.5 kg/t CMC, in the second stage and 15, respectively 20 kg/t of cationic starch in the third stage. These quantities were calculated in relation to the mixed part, which amounted to 45% by weight of the entire composition. Thus, the amount of added polymer, based on the entire weight of the composition, amounted to 6.75 kg/t of cationic starch in the first stage; 0,675 kg/t CMC in the second stage and 6.75, respectively 9, kg/t of cationic starch in the last stage.
In the processing of pulp during three successive stages of the first two polymer additives produced in the tank for pulp, and the latest addition of cationic starch produced in production lines in the pipeline.
Measured strength values Scott-Bond samples of cardboard; the results are presented in chart 1.
Chart 1 shows that the strength of cardboard in polymer processing only the mixed part of the composition during three successive stages even higher than the strength of cardboard, obtained from the composition, fully processed polymers during three successive stages, even though the number of added starch was less.
Determined the density of cardboard. Figure 2 shows the results of the measured strength of the Scott-Bond in comparison with the density.<>
Figure 2 shows that the density of cardboard treated with polymers, is saved in comparison with a reference sample, although the strength of the cardboard has increased.
Therefore, these tests, the results of which are presented in charts 1 and 2 show that it is preferable to process only part of the song, as the result cartons with high durability when stored volume, while the number of added polymers reduced.
1. A method of manufacturing paper or cardboard product, including:
providing paper pulp containing fibers;
polymer processing the first part (1) paper pulp, in which polymers are added to pulp in the course of performing at least two stages;
mixing the aforementioned first part subjected to polymer processing, from raw second part (2) paper pulp;
dewatering of paper pulp on a grid conveyor for forming fibrous web.
2. The method according to claim 1, in which is mentioned the first part of the paper pulp is 20-80% of the total mass.
3. The method according to claim 1 or 2, in which is mentioned the first part of the paper pulp containing the long fibers present in the paper pulp.
4. The method according to claim 1 or 2, in which the mentioned first h is any paper pulp contains sulphate or sulphite pulp fibers soft (pine) wood.
5. The method according to claim 1, in which paper pulp contains fillers and, optionally, other additives used in the manufacture of paper, with fillers and additives injected polymer after processing mentioned the first part of the paper pulp.
6. The method according to claim 1, in which paper pulp contains fillers and, optionally, other additives used in the manufacture of paper, with fillers and additives introduced to polymer processing mentioned the first part of the paper pulp.
7. The method according to claim 1, wherein the polymer used in each of the successive stages of polymer processing, interacts with the polymer used in the subsequent stage.
8. The method according to claim 1, wherein at least one of the stages of polymer processing includes adding anionic polymer and at least one of the stages of polymer processing includes adding a cationic polymer.
9. The method according to claim 8, in which the anionic polymer is carboxymethylcellulose (CMC).
10. The method according to claim 8, in which the cationic polymer is cationic starch.
11. The method according to claim 1, wherein the polymer treatment is carried out in two to seven furlongs.
12. The method according to claim 10, in which the polymer treatment is carried out in three to seven stages.
13. Cardboard product manufactured according to the method according to claim 1.
14. Paper manufactured according to the method according to claim 1.
FIELD: textile; paper.
SUBSTANCE: method (in version) concerns paper manufacturing and can be applied in pulp and paper industry. Method involves: (i) supply of water suspension containing pulp fiber, (ii) adding to suspension after the last point of severe shear force exposure of: (a) first anion component of anion organic polymer soluble in water; (b) second anion component of anion organic polymer dispersed in water or branched organic polymer; and (c) third anion component of anion material containing silicon; and (iii) dehydration of obtained suspension to produce paper. Also invention concerns composition (in version) including first, second and third anion components, and application of the composition as flocculation agent in production of pulp mass and paper for water treatment.
EFFECT: improved water drainage and retaining during paper manufacturing out of any type of pulp suspensions, accelerated operation of paper-making machine, reduced polymer dosage applied.
56 cl, 3 tbl, 4 ex
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: 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: textile; paper.
SUBSTANCE: method relates to production paper material and can be applied in paper-and-pulp industry when producing paper material with low-density. Method includes formation of aqueous suspension containing pulp. Addition of latex with agglomerated hollow particles in suspension. Formation of a wet sheet from the suspension and drying of the sheet. It also relates to paper material prepared by using the method.
EFFECT: production of paper material having good combination of optical, mechanical, tactile properties, evenness and volume including economical efficiency of the process.
10 cl, 6 dwg, 2 ex
SUBSTANCE: absorbing cloth from a cellulose fiber contains an admixture of hard wood and soft wood fibers located in the form of mesh structure, including: the set of columnar areas fibers conglomeration with relatively high local density, aggregated by means of set of the connecting areas with lower local density, where orientation of fibers is inclined along a longitudinal direction between the columnar areas interconnected in a such way, where the cloth possesses coefficient of elongation in a cross-section direction, which is at least in 2.75 times higher than relative strength at cloth stretching in a dry condition. The above-stated material is obtained as follows. A water cellulose composition from hard wood fibers is prepared. The composition is moved on a forming tissue in the form of a stream which is let out from a pressure head box with a flow rate. The composition is dehydrated and compacted for manufacturing of a paper for formation of the fibrous layer possessing chaotic distribution of a fiber for paper manufacturing. Packing of the dehydrated fibrous layer possessing chaotic distribution of a fiber on the transporting transferring surface moving with the first rate. Creping of a fibrous layer from the transferring surface on a tape at dryness from 30% to 60% with use of the pattern creping tape. The creping stage is carried out under pressure in a contact zone of the creping tape confined between the transferring surface and the creping tape. Thus the tape is moved with the second speed, lower than speed of the transferring surface. Tape drawing, parametres of a contact zone, speed difference and dryness of the fibrous layer are chosen in such way to crepe the fibrous layer at its removal from the transferring surface and to redistribute on the creping tape with formation of a fibrous layer with mesh structure. Drying of the fibrous layer is performed after. The process is regulated so that coefficient of elongation in a cross-section direction is, at least, approximately in 2.75 times higher than relative strength at stretching of the fibrous layer in a dry condition. Such method allows obtaining a cellulose fibrous layer for products made from thin paper, and also products in the form of towels.
EFFECT: improvement of ready product quality and power consumption decrease.
33 cl, 10 dwg, 22 tbl
FIELD: textiles; paper.
SUBSTANCE: composition is meant for improving the softness of paper products. Composition includes: (i) oil, fat or wax; (ii) at least one non-ionic surfactant; (iii) at least one anion compound, selected from anionic micro-particles and anionic surfactant; (iv) at least one polymer, which is a cation, non-ionic or amphoteric, where the non-ionic surfactant is added to the amount from about 60 to 1000 weight fractions for 100 weight fractions of the polymer. Composition is used in the method of manufacturing paper (versions). Method includes adding the mentioned composition to a cellulose suspension or to a moist or dry paper fabric.
EFFECT: increase in the quality of the paper products due to the increase in its softness, low resistance to tearing and high speed of getting wet and reduction in energy for pulping.
22 cl, 9 tbl, 9 ex
SUBSTANCE: invention can be used for production of deposited calcium carbonate used as paper filler. Secondary particle diameter of deposited calcium carbonate is 1-10 mcm. Deposited calcium carbonate consists of aggregated primary particles of spindle calcium carbonate with greater particle diameter within 0.5 to 3.0 mcm, smaller diameter within 0.1 to 1.0 mcm with ration of specified diameters equal to 3 or more. Specific surface area BET of primary particles of calcium carbonate is 8-20 m2/g, cell volume is 1.5-3.5 cm3/g. Method of production of deposited calcium carbonate includes as follows. Carbon dioxide or carbon dioxide gas is injected in calcium hydroxide suspension concentrated 100-400 g/l, prepared by wet calcined liming activity of which 4 "н." HCl at third minute value is reduced to 150-400 ml. Reaction is resulted in carbonisation degree within 50 to 85%. Then 1 to 20 vol % of calcium hydroxide suspension is added. Reaction is complete with injection of carbon dioxide or carbon dioxide gas. The paper containing the specified calcium carbonate as filler is offered as well.
EFFECT: enhanced paper bulkiness.
7 cl, 2 tbl, 10 ex
FIELD: textiles, paper.
SUBSTANCE: paper or cardboard of improved rigidity and bulk are meant for reproducing equipment and the method refers to production of the said paper and cardboard. The paper or cardboard has the core layer and starch-based layers applied by gluing-up on its both sides forming the uniform canvas of the double-T structure. The layers cover the upper and the lower surface of the central layer with minimal penetration to the central layer. The starch contains the filler spreading to the central layer. The starch has high content of solid products. The mass of the coating layers is 2-10 g/m2. Method for producing paper or cardboard includes the following stages: a) creation of composition containing cellulose fibers and the filler, b) formation of fibrous canvas, c) drying of the fibrous canvas, d) processing by gluing-up both sides of the dried canvas with the starch with filler and e) drying of the fibrous canvas with formation of the three-layer making the uniform canvas material with the double-T structure.
EFFECT: increased quality of paper or cardboard due to increased smoothness, decreased hygroscopic expansivity, improved fold resistance and paper rolling resistance.
30 cl, 2 dwg, 3 tbl, 3 ex
FIELD: textile; paper.
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