A method of manufacturing paper

 

(57) Abstract:

The methods relate to the manufacture of paper and can be used in the pulp and paper industry. Paper is made from a suspension containing cellulosic fibres, and optional fillers. The method includes introducing into the suspension means of dewatering and retention, which are used cationic or amphoteric polysaccharide, forming and dewatering the suspension on the grid. When this polysaccharide contains a hydrophobic group containing an aromatic group or a polysaccharide, has the General structural formula R-(-A-N+(R1R3)-R2)nX-where R is the residue of a polysaccharide; And - the group that adds nitrogen to the residue of a polysaccharide; each of R1and R2is hydrogen or alkyl containing from 1 to 3 carbon atoms;3the hydrophobic hydrocarbon group containing at least 2 carbon atoms; n is an integer from about 2 to about 300000, or the radicals R1, R2and R3together with the nitrogen form an aromatic group containing from 5 to 12 carbon atoms; and X-- anionic counterion. Proposed technical result is improved dewatering and/or retention, and increased the e relates to the manufacture of paper, more specifically to a method of making paper, which paper weight add cationic or amphoteric polysaccharide containing hydrophobic Deputy. This method provides improved dewatering and retention, and improved strength in the dry state securities obtained in this way.

In paper production of aqueous suspension containing cellulosic fibres, and optional fillers, called paper pulp, served in the pressure vessel, from which the pulp is ejected for forming the grid. Water drains from the pulp on the forming wire, so that the grid is forming a wet paper web, and this canvas is further dewatered and dried in the drying zone of the paper machine. Water resulting from dewatering of the pulp, called white water, which usually contains fine particles such as fine fibers, fillers and additives, usually recycle the paper manufacturing process. Part of the pulp is traditionally injected additives that facilitate dewatering and retention, in order to speed up the process of dehydration and increase the absorption of small particles in a pulp fibers, so they kept these fibers on the grid. VK cationic starch and cationic guar-resin. Polysaccharides can be used separately or in combination with other polymers and/or anionic microtelecom materials such as, for example, anionic mineral particles, such as colloidal silicon dioxide. Cationic and amphoteric polysaccharides are widely used as agents increase the strength in the dry state, are introduced into the paper pulp with the aim of obtaining paper with improved strength in the dry state.

Cationic polysaccharides are usually obtained by the reaction of the polysaccharide with a quaternization agent, such as 3-chloro-2-hydroxypropyltrimethylammonium, 2,3-epoxypropyltrimethylammonium and 2-chloroethylnitrosourea.

U.S. patents 4388150; 4755259; 4961825; 5127994; 5643414; 5447604; 5277764; 5607552; 5603805 and 5858174 and European patent 500770 disclose the use of cationic and amphoteric anionic polysaccharides and mineral particles as additives to the pulp in paper production. Now these supplements are among the most effective means of dewatering and retention.

In accordance with the present invention it was found that improved dewatering and retention can be achieved in the manufacture of paper is arid, containing hydrophobic substitution group, i.e. hydrophob. It was also found that the cationic and/or amphoteric polysaccharide containing a hydrophobic group, provides superior strength of the paper in a dry condition. In particular, the present invention relates to a method of making paper from a suspension containing cellulosic fibres, and optional fillers, which comprises adding to the slurry dewatering and retention means comprising cationic or amphoteric polysaccharide, forming and dewatering the suspension on the grid, while the polysaccharide contains a hydrophobic group. The present invention also relates to a method of making paper from a suspension containing cellulosic fibres, and optional fillers, which comprises adding to a suspension agent to increase paper strength in the dry state, comprising cationic or amphoteric polysaccharide, forming and dewatering the suspension on the grid, while the polysaccharide contains a hydrophobic group. In a preferred aspect of the invention the method also includes forming and dewatering the suspension on the grid with the aim of getting wet paper web containing pulp fibers, or Bergama cellulosic fibers and optional fillers and subject to dehydration with the aim of obtaining paper the number of input of fresh water is less than 30 tons per ton of dry received paper. Thus, the present invention relates to a method, hereinafter defined in the claims.

The result of the present invention are improved dewatering and/or retention, and therefore, the present invention allows to increase the speed of the paper machine and to use a lower dosage of additives, to provide the corresponding effect of dehydration and/or retention, ultimately leading to improved paper manufacturing process and economic benefits. Other benefits observed when carrying out the present invention include improved strength of the paper in the dry state obtained with the use of polysaccharide containing a hydrophobic group. Here is also possible to use a smaller amount of an agent that increases the strength of the paper in the dry state to provide the necessary strength. The method according to the invention is also suitable for the processing of pulp suspensions in closed process, where white water re-recycle with the introduction of only small amounts of fresh water. This method is also acceptable is applicable to PR is the use of salts and having thus, high levels of conductivity, for example, processes with extensive recirculation of white water and the limited supply of fresh water, and/or processes involving the use of fresh water having a high salt content.

The polysaccharide of the present invention may be selected from any known polysaccharides, including, for example, starches, gum-resins, cellulose, chitina, chitosans, glikana, galactanes, glucans, xanthan gums, pectins, mannans, dextrins, preferably starches and gum-resin. Examples of suitable starches include potato, corn, wheat, tapioca, rice, waxy maize, etc. are Acceptable, when the cationic polysaccharide is a water-dispersible or preferably water-soluble. In a preferred embodiment of the present invention, the polysaccharide may act as agent (the agent) dewatering and retention. The term "means of dewatering and retention", used in the present description, refers to one or more components (tools, agents or additives), which, when introduced into the slurry, provide the best dehydration and/or retention as compared with the case, to the population of the present invention, the polysaccharide may act as an agent to increase strength in the dry state. Used in this description, the term "agent increase the strength in the dry state" refers at least to the same component (tool, agent or additive), which when introduced into the pulp provides the best indicators of the strength of the paper in a dry condition compared to pulps, in which the specified component is not entered.

The polysaccharide is a substituted hydrophob, cationic or amphoteric, i.e., a polysaccharide containing one or more hydrophobic groups and one or more cationic groups, cationic groups are acceptable tertiary amino group or, preferably, Quaternary ammonium group. The polysaccharide may also contain one or more anionic groups, which may be, for example, phosphate, phosphonate, sulphate, sulphonate or carboxylate groups, and preferably they represent phosphate groups. Anionic groups, if present, can be native or introduced by chemical treatment by known methods; natural potato starch contains a significant number of covalently linked phosphate groups of the complex monoether. In the amphoteric polysaccharides of the cationic group predpochtite is inane to the heteroatom, such as oxygen contained in the polysaccharide. Preferably, when a hydrophobic group attached to the heteroatom, for example nitrogen or oxygen heteroatom optionally has a charge, for example, when it is a nitrogen atom or a group that includes such a heteroatom, such as amide, ester or ether, which, in turn, can be attached to the polysaccharide chain (main chain), for example, through a chain of atoms. The hydrophobic group contains at least 2, usually at least 3 acceptable at least 4 and preferably at least 6 carbon atoms; and generally up to about 20 acceptable up to 14 and preferably up to 12 carbon atoms. The hydrophobic group may be selected from aromatic (aryl) groups, aliphatic hydrocarbon groups and mixtures of such groups. Examples suitable for use hydrophobic aliphatic groups include linear, branched and cyclic alkyl groups such as ethyl; propyl, such as n-propyl and isopropyl; butyl, such as n-butyl, isobutyl and t-butyl; pentyl, for example n-pentyl, neopentyl and isopentyl; hexyl, such as n-hexyl and cyclohexyl; octyl, for example n-octyl; decyl, such as n-decyl; and dodecyl, for example, n-dodecyl, and tetradecyl. Examples of suitable for iseppi, for example the phenyl, phenylene, naphthyl, phenylene, xylylene, benzyl and phenylethyl; nitrogen-containing aromatic (aryl) groups, for example, pyridine and chinoline, as well as derivatives of these groups, one or more of the substituents attached to these aromatic groups may be selected from among such groups as hydroxyl, halides, for example chloride, nitro and hydrocarbon groups containing from 1 to 14 carbon atoms.

Especially suitable for use polysaccharides of the present invention include those described General formula (I):

< / BR>
where R denotes the residue of a polysaccharide; a represents a group that adds nitrogen to the residue of the polysaccharide, an acceptable chain of atoms comprising carbon atoms and hydrogen, and optionally oxygen atoms and/or nitrogen, usually alkylenes group containing from 2 to 18 and acceptable from 2 to 8 carbon atoms, optionally interrupted or substituted by one or more heteroatoms, for example oxygen or nitrogen, such as accelerograph or hydroxypropionate group (-CH2-CH(OH)-CH2-); each of the radicals R1and R2represents hydrogen or, preferably, a hydrocarbon group, an acceptable alkyl, provided glevodorodnogo group, containing at least 2 carbon atoms, acceptable 4-14 and preferably 6-12 carbon atoms, the hydrophobic group is acceptable is a group as defined above, preferably a group selected from alkyl and kalkilya groups such as benzyl and phenylethylene group; n is an integer from about 2 to about 300000 acceptable from 5 to 200,000 and preferably from 6 to 125,000, or Vice versa, the radicals R1, R2and R3together with the nitrogen atom form an aromatic group containing from 5 to 12 carbon atoms; and X-means anionic counterion is a halide, such as chloride.

Modified hydrophobic group of the cationic or amphoteric polysaccharide may have a degree of substitution in a wide range of values; the degree of cationic substitution (DSc) may be from 0.01 to 0.5, acceptable from 0.02 to 0.3, preferably from 0.025 to 0.2, the degree of hydrophobic substitution (DSn) may be from 0.01 to 0.5, acceptable from 0.02 to 0.3, preferably from 0.025 to 0.2, and a degree of anionic substitution (DSA) can range from 0 to 0.2, acceptable from 0 to 0.1, preferably from 0 to 0.05.

The polysaccharides of the present invention can be obtained by cationic and hydrophobic monnoo group and/or a hydrophobic group, for example, by the reaction of the agent with a polysaccharide in the presence of alkaline compounds such as alkali metal hydroxide or alkaline earth metal. Polysaccharide subjected to cationic or hydrophobic modifications may be nonionic, anionic, amphoteric or cationic. Suitable for use of modifying agents include non-ionic agents, such as, for example, substituted by hydrofoam succinate anhydrides; alkalinity, such as propylene oxide and butylenes; alkylhalogenide, such as decembered and dodecylamide; aralkylamines, such as benzylchloride and benzylbromide; the reaction products of epichlorohydrin with dialkylamines containing at least one substituent comprising a hydrophobic group that is defined above, including 3-dialkylamino-1,2-epoxypropane; cationic agents such as, for example, the reaction product of epichlorohydrin and tertiary amines containing at least one substituent comprising a hydrophobic group that is defined above, including trialkylamine, alaricdailey, such as dimethylbenzylamine; arylamine, such as pyridine and quinoline. Suitable for use cationic agents of this type include 2,3-epoxypropyltrimethylammonium, kalogeraki Manihari and N-glycidyl-N-(hydrophobic alkyl)-N, N-di(lower alkyl)ammoniacal, where the hydrophobic alkyl group is as defined above, mainly octyl, decyl and dodecyl, and the lower alkyl is methyl or ethyl; and halohydrocarbon-N,N-dialkyl-N-alkalinemanganese and N-glycidyl-N-(alkaryl)-N,N-dialkylammonium, for example N-(3-chloro-2-hydroxypropyl)-N-(alkaryl)-N,N-di(lower alkyl)ammoniacal, where alkaryl and lower alkyl groups are those defined above, especially N-(3-chloro-2-hydroxypropyl)-N-benzyl-N,N-dimethyl-ammoniacal; and N-(3-chloro-2-hydroxypropyl)pyridine-chloride. Typically, when used non-ionic hydrophobic agent, the polysaccharide becomes acceptable cation when using any known cationic agents before or after the hydrophobic modification. Examples of usable cationic and/or hydrophobic modifying agents modified with a hydrophobic group of polysaccharides and methods for their preparation include those described in U.S. patents 4687519 and 5463127; international patent application WO 94/24169, European patent application 189935; and S. P. Patel, R. G. Patel and V. S. Patel, Starch/Starke, 41 (1989), No 5, pp. 192-196, which are introduced in this application by reference.

In a preferred embodiment, the polysaccharides of the present izopet the further improvement of dehydration and/or retention, thus providing a means of dewatering and retention, containing two or more components, usually referred to by means of dewatering and retention. Used in the present description, the term "means of dewatering and retention" refers to two or more components (tools, agents or additives), which when introduced into the pulp give the best dehydration and/or retention than can be achieved without the addition of these components. Examples of usable additives pulp of this type include anionic mikrosmeshcheniya materials, such as anionic organic particles and anionic mineral particles, water-soluble anionic vinyl polymers accession, low molecular weight cationic organic polymers, aluminum compounds, and combinations thereof. In a preferred implementation of the present invention, the polysaccharide used in combination with anionic microtelecom material, mainly anionic mineral particles. In another preferred embodiment, the polysaccharide used in combination with anionic mineral particles and low molecular weight cationic organic polymer. In another preferred embodiment, assests microecology material according to the present invention may be chosen from mineral and organic particles.

Anionic mineral particles, which can be used according to the present invention include anionic particles based on silica and clay smectite type. Preferably, anionic mineral particles were in the size range of colloidal particles. Anionic particles on the basis of silicon dioxide, i.e. particles based on SiO2or silicic acid, preferably used, and such particles are normally supplied in the form of aqueous colloidal dispersions, the so-called sols. Examples of usable particles on the basis of silicon dioxide include colloidal silicon dioxide, and various types of polysilicon acid. Sols on the basis of silicon dioxide can also be modified and can contain other elements, such as aluminum and/or boron, which can be contained in the aqueous phase and/or particles on the basis of silicon dioxide. Suitable for use particles based on silica of this type include colloid-modified aluminium silicon dioxide and aluminum silicate. Can also be used mixtures of these are suitable for use particles on the basis of silicon dioxide. Means of dewatering and retention, including suitable for COI; 176891; 5368833; 5447604; 5470435; 5543014; 5571494; 5573674; 5584966; 5603805; 5688482 and 5707493, which is incorporated into the present application by reference.

Anionic particles based on silica acceptable have an average particle size of less than about 50 nm, preferably less than about 20 nm and more preferably in the range from about 1 to about 10 nm. As is customary in the chemistry of silica, the particle size refers to the average size of the primary particles, which can be aggregated or not aggregated. The specific surface of particles based on silica acceptable is approximately 50 m2/g and preferably more than 100 m2/, Usually specific surface area may be approximately up to 1700 m2/g and preferably up to 1000 m2/g Specific surface area can be measured by titration of NaOH in a known manner, for example, as described by Sears in Analytical Chemistry 28(1956):12, 1981- 1983 and in U.S. patent 5176891. Thus, the value of specific surface area represents the average specific surface of the particles.

In a preferred embodiment of the present invention anionic mineral particles are particles on the basis of silicon dioxide having a specific surface area in Diago also encompass modified sols, such as aluminium-containing sols based on silicon dioxide, boron sols based on silicon dioxide. Preferably, when the particles based on silica are present in the ashes, having an S-value in the range from 8 to 45%, preferably from 10 to 30%, and containing particles based on silica with a specific surface area in the range from 300 to 1000 m2/g acceptable from 500 to 950 m2/g and preferably from 750 to 950 m2/g, as noted above, such sols can be modified with aluminum and/or boron. For example, the surface of the particles can be modified with aluminium to the extent of 2 to 25% substitution of silicon atoms. S-value can be measured and calculated as described by Iler & Dalton, J. Phys. Chem. 60(1956),955-957. S-value indicates the degree of aggregation or formation of microgel, and lower S-values indicate a higher degree of aggregation.

In another preferred embodiment of the present invention the particles based on silica selected from polysilicon acid and a modified polysilicon acid having a high specific surface area, acceptable than about 1000 m2/g Specific surface area can be in the range led the lots may contain other elements, for example, aluminum and/or boron, which may be present in the aqueous phase and/or particles on the basis of silicon dioxide. In this chemistry polysilicon acid also referred to as polymeric silicic acid, microgel polysilicon acid, polysilicate and the polysilicate microgel, which are all covered used in this application, the term polysilicon acid. Aluminium-containing compounds of this type are often also referred to as polyaluminosilicate and microgel of polyaluminosilicate that both covers used in the present description the terms colloid-modified aluminium silicon dioxide and aluminum silicate.

Clay smectite type, which can be used in the method of the present invention, are known and include natural, synthetic and chemically treated materials. Examples suitable for use smectite clays include montmorillonite/bentonite, hectorite, beidellite, nontronite and saponite, preferably bentonite and especially bentonite, which after swelling preferably has a specific surface area of from 400 to 800 m2/, Suitable for use clay are disclosed in U.S. patents 4753710; 5071512 and 5607552, which are included in this steamemu the invention, include anionic vinyl polymers attach with a high degree of cross-linkage, acceptable copolymers comprising anionic monomer such as acrylic acid, methacrylic acid, and sulfonated or Vospominanie vinyl monomers that polymerize on the mechanism of joining, usually copolymerisate with nonionic monomers such as (meth)acrylamide, alkyl(meth)acrylates, etc. Suitable for use anionic organic particles also include anionic condensation polymers, such as sols malminkartano acid.

Low molecular weight (hereinafter MMOs) cationic organic polymers which can be used according to the present invention include those that are called and used as anionic musorofiti (AMU). AMU known as neutralizing and/or fixing agents for harmful anionic substances present in the pulp, and their use in combination with drying and retaining means often provides a further improvement in the dewatering and retention. MMOs cationic organic polymer may be natural or synthetic, and preferably it is an MMO synthetic polymer. Suitable for home, such as polyamine, polyamidoamine, polyethyleneamine, Homo - and copolymers based diallyldimethylammoniumchloride, (meth)acrylamide and (meth)acrylates. Molecular weight MMO cationic organic polymer is acceptable is not less than 2000 and preferably not less than 10000. The upper limit of molecular weight is usually approximately 700,000 acceptable approximately 500,000 and is usually about 200,000.

Aluminum compounds which can be used according to the present invention, include alum, aluminates, aluminium chloride, aluminum nitrate and semi-aluminum compounds such as the chlorides of polyalanine, sulfates of polyalanine, semi-aluminum compounds containing both ion - chloride and sulfate, silicate-sulphate of polyamine and mixtures thereof. Semi-aluminum compounds can also contain other anions other than chloride ion, for example anions from sulfuric acid, phosphoric acid, organic acids such as citric acid and oxalic acid.

The components of the dewatering and retention means according to the present invention can be added to the pulp in the usual way and in any order. When using anionic microtrenching material predpochtiteljno material, even if you can use a reverse order of introduction. Also preferably the polysaccharide before the phase shift, which you can choose from operations, pumping, mixing, clarification, and so on, and enter the anionic particles after such a phase shift. When applied MMO cationic organic polymer or a compound of aluminum, such components are preferably introduced into the pulp prior to the introduction of polysaccharide and an anionic microtrenching material, if used. Conversely, MMOs cationic organic polymer and polysaccharide can be introduced into the pulp almost simultaneously, either separately or in mixture, for example, as disclosed in U.S. patent 5858174, which is included in the present description by reference.

The agent increasing the strength of the paper in a dry condition and a means of dewatering and retention according to the present invention is introduced into a subject to dehydration of the slurry in amounts which can vary within wide limits depending on, inter alia, the type and number of components, type of pulp, filler content, type of filler, the point of injection, salt, etc. Usually these component(s) are added in amounts that achieve the best strength . alseny hydrofoam cationic or amphoteric polysaccharide usually added in an amount of not less than 0.01%, often at least 0.1% by weight based on the weight of dry matter of the pulp, and the upper limit is usually 10% and an acceptable 2% by weight. When using anionic microecology material, it is usually added in an amount of not less than 0.001% by weight, often not less than 0,005% by weight, calculated on the dry matter of the pulp, and the upper limit is usually 1.0% and acceptable to 0.6% by weight. When using anionic particles based on silica, the total input number is acceptable value in the range of 0.005 to 0.5% by weight, based on the SIO, SIS2by weight of solids of the slurry, preferably in the range from 0.01 to 0.2% by weight. When used in this way MMOs cationic organic polymer can be entered in the amount of not less than 0.05% based on the weight of solids to be dewatered pulp. Acceptable, when this amount is a value lying in the range from 0.07 to 0.5%, preferably in the range from 0.1 to 0.35%. In the case when the implementation of this method uses a compound of aluminum, the total number entered in padeliadu the measures well aware of the use of aluminum compounds as precipitators for sizing agents based on rosin. Usually the total input quantity is not less than 0.05%, based on A12ABOUT3and the weight of dry matter. Acceptable, when this amount is a value lying in the range from 0.5 to 3.0%, preferably in the range of from 0.1 to 2.0%.

The method of the present invention is preferably used in the manufacture of paper from a suspension containing cellulosic fibres, and optional fillers and having a high conductivity. Usually the conductivity of the pulp, which is dehydrated on the net, is a minimum of 0.75 MS/cm, acceptable not less than 2.0 MS/cm and preferably not less than 3.5 MS/see Very good results in dehydration and retention were observed in the levels of specific conductivity of about 5,0 MS/cm and even more than 7.5 MS/see conductivity can be measured on standard equipment, such as, for example, the device WTW LF 539 shipped Christian Berner. The above acceptable values are determined by measuring the conductivity of the pulp suspension which is fed into the pressure vessel or which is in pressure e is in the dehydration of the suspension. High levels of conductivity indicate a high content of salts (electrolytes), various salts can be based on one-, two - and multivalent cations, such as cations of alkali metals such as Na+and+, alkaline earth metals, such as CA2+and Mg2+, ions of aluminum, for example A13+A1(HE)2+and ions of polyalanine, and one-, two - and multivalent anions, such as halides, for example C1-, sulfates, for example SO42-and HS4-, carbonates, such as CO32-and the HCO3-, silicates and lower organic acids. The present invention is particularly applicable in the production of paper from pulp having a high content of salts of two - and multivalent cations, and usually the cations is not less than 200 parts per million , acceptable not less than 300 parts per million and preferably not less than 400 parts per million Source of salts can be cellulose fibers and fillers used to obtain pulp, in particular, on individual plants, where the concentrated aqueous suspension of fibers of a papermaking plant usually mixed with water to give a dilute suspension, suitable for issuesa water, fed to the process, and they can be added intentionally, etc. in Addition, the salt content is usually higher in those processes in which extensive recirculation of white water, which can lead to significant accumulation of salts in the water circulating in the process.

Further, the present invention encompasses methods of making paper, which is widely recycled white water, i.e. with a high degree of use of white water, for example, where use from 0 to 30 tons of fresh water per ton of dry paper, usually less than 20 acceptable less than 15, preferably less than 10 and significantly less than 5 tons of fresh water per tonne of paper. Recirculation of white water obtained in the process, acceptable includes a mixture of white water and cellulose fibers and/or optional fillers with the formation of the suspension, subject to dehydration; preferably, when it involves the mixing of white water suspension containing cellulosic fibres, and optional fillers, before the suspension will go on forming a grid for dehydration. White water can be mixed with the suspension before, between, simultaneously with or after the introduction of dehydrating and restraint devices, if tocovyrol stage; for example, it can be mixed with cellulose fibers in order to obtain a suspension, and it can be mixed with containing pulp fiber suspension with a view to its dilution, so as to form the suspension to be dewatered before or after mixing the pulp with white water and before, between, simultaneously with or after the introduction of the components of dehydrating and restraint devices, if used; and to, simultaneously with or after administration of the polysaccharide.

Of course, other additives, which are traditional for the paper industry, can be used in combination with the additives of the present invention, such as, for example, the agents increase the strength in the dry state, the agents increase the strength in the wet state, agents, optical bleaching, sizing agents, such as sizing agents based on rosin, the ketene dimer and the anhydrides of the acids, optical brighteners, dyes, etc. Pulp suspension, or slurry, may also contain mineral fillers of conventional type, such as, for example, kaolin, China clay, titanium dioxide, gypsum, talc and natural and synthetic calcium carbonates such as chalk, ground marble and O. ispolzovanny in the present description, the term "paper", of course, includes not only paper and its production, but also other sheet or roll products, such as, for example, paperboard (weight up to 250 g/cm3and thin cardboard, and their production. This method can be used for the production of paper from different types of suspensions of cellulose fibers, and such suspension shall be acceptable to contain not less than 25% by weight and preferably not less than 50% by weight of such fibres calculated on the dry matter. These suspensions can be based on fibres from chemical pulp, such as sulphate, sulphite and organosilanes pulp, mechanical pulp, such as thermo-mechanical pulp, chemo-thermomechanical pulp, refiner pulp and wood-fibre pulp from both coniferous and deciduous wood, and may be based on fiber secondary processing optional wood mass after removal of dyes and their mixtures. The present invention is particularly suitable for the manufacture of paper from a suspension on the basis of the pulps, including fiber recycling, and pulp after removal of paint, and the content of cellulose fibers such an origin can be up to 100%, item is which, however, do not limit the scope of its claims. Parts and % are parts by weight and % by weight, respectively, if no special instructions.

Example 1. Cationic polysaccharides get the reaction of natural potato starch with a quaternization agent in accordance with the General method described in European patent application 189935. Agents quaternization of supplies industry, for example, the firm Degussa, or they can be prepared according to the General procedure described in U.S. patent 5463127. The starch is dissolved in water and used in the form of a 0.5% aqueous solutions.

The polysaccharides of the present invention, from P1 to P3, and polysaccharides that are intended for comparative purposes, Ref. l and Ref.2, is prepared from the following starting materials:

P1: Cationic starch obtained by quaternization of natural potato starch with 3-chloro-2-hydroxypropyltrimethylammonium to 0.8% n

P2: Cationic starch obtained by quaternization of natural potato starch with 3-chloro-2-hydroxypropyltrimethylammonium to 1.3% n

P3: Cationic starch obtained by quaternization of natural potato starch with 3-chloro-2-hydroxypropylmethacrylate is making a movie using 3-chloro-2-hydroxypropyltrimethylammonium to 0.8% n

Ref. 2: Cationic starch obtained by quaternization of natural potato starch using 2,3-epoxypropyltrimethylammonium to 1.3% n

Example 2. The effect of dewatering and retention assessed using a dynamic analyzer dehydration Dinamic Drainage Analyser (DDA), the company supplied Akribi, Sweden, which allows us to measure the time of dehydration certain amount of slurry passing through the grid, after removal of the tube and create a vacuum on the other side of the grid, which is opposite the side on which the pulp. Retention during the first pass of the pulp is assessed using a turbidity meter by measuring the turbidity of the filtrate, white water generated during dewatering of the pulp.

Use the furnish in the calculation of 56% by weight of peroxide bleached TMP/SGW pulp (80/20), 14% by weight of bleached birch/pine sulphate (60/40) pulp refined to 200oCSF and 30% by weight of China clay. To the pulp add 40 g/l colloidal fraction, clarified water from SC plant, filtered through a mesh grille calibre 5 μm and concentrated on the UV filter, the fraction of 200,000. The amount of paperwork mixture of 800 ml and a pH of about 7. To the pulp add calcium chloride to dovecote with turbulization flow with a speed of 1500 rpm during the whole experience, and chemical additives injected as follows: i) to introduce the polysaccharide in the mixture, followed by stirring for 30 seconds, ii) to introduce anionic mineral particles in the mixture, followed by stirring for 15 seconds, (iii) dehydrating the mixture and automatically record the time of dehydration.

The polysaccharides used in a series of experiments, represent P1 and Ref. l as in example 1. Used anionic mineral particles are particles based on silica of the type disclosed in U.S. patent 5368833. Sol has 3-approximately 25% and contains particles of silicon dioxide with a specific surface area of about 900 m2/g, which surface is modified with aluminium to the extent of 5%.

Table 1 shows the effect of dewatering and retention at various dosages of cationic starch, calculated on the dry starch dry residue slurry and particles on the basis of silicon dioxide, per SIO, SIS2on a dry residue is obtained.

Example 3. In this series of experiments the effect of dehydration evaluated according to the procedure described in example 2.

Use the same composition of the paper as in example 2. Loading capacity of 800 ml and a pH of about 7. In the paper the mixture was added chloride is 7).

In this series of experiments using polysaccharides P2 and Ref.2, as in example 1. In this series of experiments similar to use anionic mineral particles, as in example 2.

Table 2 shows the effect of dehydration at different dosages funds dewatering and retention in the calculation of the dry starch and SiO2dry the remainder of the paper pulp.

Example 4. In this series of experiments the effect of dehydration evaluated according to the procedure described in example 2, except that the funds dewatering and retention also include low molecular weight cationic polyamine; AMU. To the pulp add polyamine, and then stirred for 30 seconds prior to the introduction of cationic polysaccharide, and then anionic mineral particles.

Use a paper composition on the basis of 70% of the pulp after paint removal, 15% by weight of peroxide bleached TMP/SGW pulp (80/20) and 15% by weight of bleached birch/pine sulfate pulp (60/40), ennobled 200oCSF. The volume of the mixture was 800 ml and a pH of about 7. The mixture was added calcium chloride to bring the value of the specific conductivity of 1.0 MS/cm (Experiment 1), 2.0 MS/cm (Experiment 2), to 4.0 MS/cm (Experiments 3-4) and 7.5 MS/cm (Experiment 5).

In this series of experiments using polysaccharides P1, P2,blitz 3 shows the effect of dewatering at various dosages funds dewatering and retention per dry polyamine, starch and SIO, SIS2on the dry rest of the mixture.

Example 5. The strength of the paper in the dry state estimate using a Dynamic Sheet Former (Formette Dynamique) supplied by the company Fibertech AB, Sweden, and dynamometer Tensile Strength Tester supplied by the company Lorentzen &Wettre, Sweden. The effect of dehydration evaluated according to the procedure described in example 4.

Use the composition of the paper, as the example 2. The consistency of the mixture is 0.3%. Conductivity of the mixture adjust by adding calcium chloride. In this series of experiments use the same additives and the order of their entry, as in example 4. The polyamide is added in an amount of 3 kg/ton, based on dry polyamide dry residue mixture. Particles on the basis of silicon dioxide is added in an amount of 3 kg/t, based on SiO2on the dry rest of the mixture.

Paper sheets formed into Dynamic Sheet Former by adding chemical additives to the mixture in the mixing chamber, pumping the mixture through moving the nozzle in a rotating drum in a water film on the top of the grid, dehydration of the mixture and formation of the sheet, pressing and drying the sheet. The leaves are cut into strips, which carry out measurements on the dynamometer Tensile Strength Tester. Calculate and compare the standard is>Table 4 presents the time performance of the dewatering and tensile strength at break of the sheets obtained under different dosages of starch, based on the dry starch on a dry residue of the mixture.

1. Method of making paper from a suspension containing cellulosic fibres, and optional fillers, comprising adding to the suspension means of dewatering and retention, including cationic or amphoteric polysaccharide, forming and dewatering the suspension on the grid, characterized in that the polysaccharide contains a hydrophobic group, which includes an aromatic group.

2. The method according to p. 1, characterized in that the hydrophobic group is a benzyl group.

3. The method according to any of the preceding paragraphs, characterized in that the hydrophobic group contains from 4 to 14 carbon atoms.

4. The method according to any of the preceding paragraphs, characterized in that the hydrophobic group contains from 6 to 12 carbon atoms.

5. The method according to any of the preceding paragraphs, characterized in that the polysaccharide is selected from starch and gum-resins.

6. The method according to any of the preceding paragraphs, characterized in that the polysaccharide contains one or more of dobavlaut in an amount not less than 0.1% by weight calculated on the dry matter of the mixture.

8. The method according to any of the preceding paragraphs, characterized in that the means of dewatering and retention includes anionic microecology material.

9. The method according to p. 8, characterized in that the anionic microecology material selected from particles based on silica or bentonite.

10. The method according to p. 8 or 9, characterized in that the anionic microecology material selected from particles on the basis of silicon dioxide having a specific surface area of more than 50 m2/,

11. The method according to any of the preceding paragraphs, characterized in that the means of dewatering and retention also includes a low molecular weight cationic organic polymer.

12. The method according to any of the preceding paragraphs, characterized in that the suspension comprises cellulose fiber recycling.

13. The method according to any of the preceding items, wherein the suspension includes the pulp after paint removal.

14. The method according to any of the preceding paragraphs, characterized in that the dewatering on the grid suspension has a conductivity of at least 0,75 MS/see

15. The method according to p. 14 characterized in that the dewatering on the grid suspension is, characterized in that it further comprises dewatering the suspension on the grid to receive the wet paper web and white water, white water recirculation and optional introduction of fresh water to obtain a suspension containing cellulosic fibres, and optional fillers and subject to dehydration, in this case the number of input of fresh water is less than 30 tons per 1 ton of dry paper.

17. Method of making paper from a suspension containing cellulosic fibres, and optional fillers, comprising adding to the suspension means of dewatering and retention, including cationic or amphoteric polysaccharide and a component selected from anionic microtrenching materials, water-soluble anionic vinyl polymer joining and combinations thereof, forming and dewatering the suspension on the grid, characterized in that the polysaccharide contains a hydrophobic group containing an aromatic group, or polysaccharide has a General structural formula (I):

< / BR>
where R is the residue of a polysaccharide;

A group that connects the nitrogen to the residue of a polysaccharide;

R1and R2is hydrogen or alkyl containing from 1 to 3 carbon atoms;

R3the hydrophobic hydrocarbon is UB>, R2and R3together with the nitrogen form an aromatic group containing from 5 to 12 carbon atoms;

X-- anionic counterion.

18. The method according to p. 17, wherein the hydrophobic group comprises an aromatic group.

19. The method according to any of the p. 17 or 18, characterized in that the hydrophobic group is a benzyl group.

20. The method according to p. 17, wherein the hydrophobic group comprises an alkyl group.

21. The method according to p. 20, characterized in that the hydrophobic group is butyl, pentyl, hexyl, octyl or decyl.

22. The method according to any of the preceding paragraphs, characterized in that gidrofobnaya group contains from 4 to 14 carbon atoms.

23. The method according to any of the preceding paragraphs, characterized in that the hydrophobic group contains from 6 to 12 carbon atoms.

24. The method according to any of the preceding paragraphs, characterized in that the polysaccharide is selected from starch and gum-resins.

25. The method according to any of the preceding paragraphs, characterized in that the polysaccharide contains one or more anionic groups.

26. The method according to any of the preceding paragraphs, characterized in that the polysaccharide doppelseitig points, characterized in that the means of dewatering and retention includes anionic microecology material.

28. The method according to p. 27, characterized in that the anionic microecology material selected from particles based on silica or bentonite.

29. The method according to p. 27 or 28, characterized in that the anionic microecology material selected from particles on the basis of silicon dioxide having a specific surface area of more than 50 m2/,

30. The method according to any of the preceding paragraphs, characterized in that the means of dewatering and retention also includes a low molecular weight cationic organic polymer.

31. The method according to any of the preceding paragraphs, characterized in that the suspension comprises cellulose fiber recycling.

32. The method according to any of the preceding items, wherein the suspension includes the pulp after paint removal.

33. The method according to any of the preceding paragraphs, characterized in that the dewatering on the grid suspension has a conductivity of at least 0,75 MS/see

34. The method according to p. 33, characterized in that the dewatering on the grid suspension has a conductivity of at least 2 is dewatering the suspension on the grid to receive the wet paper web and the white water recirculation of white water and optional introduction of fresh water to obtain a suspension containing cellulosic fibres, and optional fillers and subject to dehydration, in this case the number of input of fresh water is less than 30 tons per 1 ton of dry paper.

 

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The invention relates to the pulp and paper industry, in particular the production of paper with surface treatment as pigmented and non-pigmented

The invention relates to aqueous compositions sizing agent and method for producing paper

FIELD: production of improved starch compositions and methods of use of improved starch compositions.

SUBSTANCE: proposed method includes use of starch component containing cationized cross-linked starch at viscosity of from 10 to 3000 cps. Production of paper includes the following stages: boiling the starch component at temperature of 165°C, dehydration of paper composition (paper fibers, inorganic filler, starch) and control of rate of dehydration and/or holding the first pass in the course of dehydration through change in temperature (by at least 10°C) of starch composition boiling.

EFFECT: possibility of performing modifications in accordance with variants on wet end of paper machine.

21 cl, 6 dwg, 2 tbl

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

FIELD: paper-and-pulp industry.

SUBSTANCE: invention relates to pigment, which can be used in manufacture of paper with filler, coated paper, and cardboard. Calcium hydroxide and calcium carbonate powders taken in proportion between 1.0:2.2 and 1.0:23.5 are added to vigorously stirred water, after which temperature of mixture is raised to 80-85°C and resulting reaction mixture is kept being stirred for 90-180 min to form dispersion of pigment containing 20-35% solids.

EFFECT: improved quality of pigment at lower cost and extended application area.

3 tbl

FIELD: pulp and paper industry; methods of production of the pigment for manufacture of the cardboard and paper.

SUBSTANCE: the invention is pertaining to the method of production of the pigment for manufacture of the cardboard and paper and may be used in pulp and paper industry at production of the filled paper, the coated paper and the cardboard. In the water at intense stirring feed powders of calcium hydrate and calcium carbonate at the ratio of the indicated components accordingly from 1.0:2.2 up to 1.0:12.9. The produced suspension is gradually added with aluminum sulfate at its ratio to the total mass of the calcium hydroxide and calcium carbonate from 1.0:0.85 up to 1.0:4.30. Then the temperature of the mixture is increased up to 8О-85°С and the produced reaction mixture is kept at stirring within 90-180 minutes with formation of the dispersion of the pigment with the share of the dry substances in it equal to 20-35 %. Then the dispersion is dried and grinded into the powder. The powder is dispersed in the water containing the given amount of the dissolved coolant and-or binding - starch or polyvinyl alcohol. The technical result of the invention production of the pigment with the new properties, that allow to expand the field of its application at manufacture of various types of the cardboard and the paper.

EFFECT: the invention ensures production of the pigment with the new properties, expansion of the field of its application at manufacture of various types of the cardboard and the paper.

2 tbl

FIELD: pulp and paper industry; methods of production of the pigment for manufacture of the cardboard and paper.

SUBSTANCE: the invention is pertaining to the method of production of the pigment for manufacture of the cardboard and paper and may be used in pulp and paper industry at production of the filled paper, the coated paper and the cardboard. Calcium carbonate is treated with aluminum sulfate in the aqueous medium. The treatment is conducted at aluminum sulfate consumption of 25-105 % to the mass of absolutely dry calcium carbonate at the temperature of 80-85°С during 90-180 minutes with production of the suspension containing 25-35 % dry substances in it. At that they use the aqueous medium containing the binding chosen from the group, which includes starch and polyvinyl alcohol in the amount of 0.5-3.0 mass % from the mass of the absolutely dry pigment, and-or the water soluble colorant in the amount of 0.1-0.5 mass % from the mass of the absolutely dry pigment. The suspension is additionally dried and grinded. The technical result of the invention is the improved quality of the pigment as well as expansion of its field of application.

EFFECT: the invention ensures the improved quality of the pigment as well as expansion of its field of application.

2 tbl

FIELD: papermaking industry.

SUBSTANCE: paper is produced from matrix obtained from composition containing pulp fibers, filler particles and retention system for said filler based on composition comprising complex of granules of ionic non-destructed swelled starch and ionic latex in aqueous carrier. Said composition contains from 60% to 95% by weight of said granules and form 40% to 5% by weight of latex of total 100 wt% on the basis of total content of solid substances of granules and latex. Granules are latex particles carriers in said complex. Processing of carrier involves producing composition of swelled starch-latex prepared in the presence of combined-action admixture or in the absence thereof, and adding said composition to filler suspension for producing of paper having improved retention of filler and allows paper to be produced, which contains filler wherein filler admixture produces minimal negative effect upon strength characteristics. Starch-latex composition may be used with compositions free of wood or with wood-containing compositions. Processed filler is readily retained in paper web in the process of paper making, improves dehydration and creates well-formed sheets. Sheets manufactured with the use of processed filler have higher adhesion strength and tensile strength as compared to sheets containing filler processed with the use of only swelled starch or only latex.

EFFECT: improved quality of paper produced with the use of starch-latex composition.

41 cl, 4 dwg, 4 tbl, 4 ex

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

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