Classifications

• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
  • D21H21/06—Paper forming aids
  • D21H21/10—Retention agents or drainage improvers
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/20—Macromolecular organic compounds
  • D21H17/21—Macromolecular organic compounds of natural origin; Derivatives thereof
  • D21H17/24—Polysaccharides
  • D21H17/28—Starch
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/20—Macromolecular organic compounds
  • D21H17/33—Synthetic macromolecular compounds
  • D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D21H17/37—Polymers of unsaturated acids or derivatives thereof, e.g. polyacrylates

Definitions

• EP-A-0 703 314 and WO 97/04168 propose the use of special cationic amylopectin starches to improve retention with the optional use of colloidal silica, anionic polyacrylamides or bentonite.
• EP-B-0 227465 describes a process for the production of paper in which, in complex sub-steps, first the fibrous material and, separately, the mineral filler with a synthetic polyelectrolyte each have the same charge and then the treated filler with a polymeric polyelectrolyte with opposite charge is treated.
• EP-B-0 282 761, WO 96/05373 and WO 96/13525 describe the modification of starch with ionic, especially cationic, polyelectrolytes.
• cationic polymers of diallyldimethylammonium chloride, N-vinylamine or N-vinylimidazoline are heated with native or already digested potato starch, while according to WO 96/05373 cationic polymers with preferably anionic starch and preferably according to WO 96/13525 are hydrolyzed , cationic polymers of N-vinylformamide, polyethyleneimines or polyalkylamines with starch of any kind are implemented.
• These starch products like starches modified with copolymers of (meth) acrylamide and dialkylamioalkyl (meth) acrylamide, are only recommended as dry strength agents for papermaking.
• modified starch which is obtained by digesting starch, starch derivatives and / or their degradation products in aqueous solution in the presence of at least one cationic polymer, built up from at least 20% by weight of polymerized di-alkylaminoalkyl (meth) acrylic acid amide -Units, which are present in protonated, preferably quaternized form, and with the addition of at least one particulate additive based on an inorganic mineral, obtained before, during or after digestion, as retention agents for pigments, inorganic fillers and fines in papermaking.
• native starch such as potato starch, wheat starch, cereal flour, maize starch, tapioca starch, sago starch and starch with an increased hydrolysis content, rice starch, pea starch and / or their mixtures
• starch degradation products in particular dextrins or oxidized starches, such as dialdehyde starch, starch derivatives, such as chemically modified derivatives Starches, especially anionic starches, such as carboxy starch and starch degraded by persulfate, anionic starch esters, such as.
• anionic starch esters such as.
• anionic starch esters such as.
• N-containing starch ethers especially starches with primary or secondary amino or imino groups and tertiary amino groups, which are positively charged by protonation with acids and contain quaternized ammonium groups.
• Cationic polymers used are homo- or copolymers of dialkylaminoalkyl (meth) acrylic acid amides which contain at least 20% by weight polymerized units of amides of (meth) acrylic acid and / or acrylic acid and preferably di-C 1 -C 2 -alkylamino-C 2 - Contain C 6 alkylamines, each of which is present in protonated or quaternized form.
• Their manufacture is, for example, in EP-A-0 013416 or in EP-A-0 113 038, the corresponding
• Such polymerized units are preferably derived from protonated or quaternized N-dialkyl-substituted (meth) acrylic acid amides, such as, for example, dimethylaminoethyl acrylamide or methacrylamide, dimethylaminopropyl acrylamide or methacrylamide, diethylaminopropyl acrylamide or methacrylamide, diethylaminoethyl acrylamide or methacrylamide, diethylaminomethyl acrylamide or methacrylamide and N ', N', dimethylamino-2,2-dimethylpropyl acrylamide or methacrylamide or mixtures thereof, which have been reacted with known quaternizing agents.
• suitable quaternizing agents are dimethyl sulfate, diethyl sulfate, methyl chloride, ethyl chloride, preferably dimethyl sulfate or methyl chloride.
• the copolymers can contain to a limited extent, preferably up to 10% by weight, sparingly water-soluble and / or water-insoluble, simply ethylenically unsaturated monomers, such as (meth) acrylic acid alkyl esters and vinyl acetate, provided the solubility of the copolymers is retained in water.
• the polymers to be used according to the invention preferably have a molecular weight MG (g / mol) in the range from 1.0 ⁇ 10 5 to 40 ⁇ 10 6 , particularly preferably in the range from 2.0 ⁇ 10 6 to 15 ⁇ 10 6 and very particularly preferably from 5 x 10 6 to 15 x 10 6 .
• the viscosity was determined using a 1% polymer solution in one
• particulate additives based on inorganic minerals can also consist of clay, preferably swellable, silica, preferably silica sol and / or with aluminum-modified polysilicates, polyorthosilicic acid, with aluminum-modified polysilicates or polyorthosilicic acid, bentonite, titanium dioxide or talc.
• clay preferably swellable, silica, preferably silica sol and / or with aluminum-modified polysilicates, polyorthosilicic acid, with aluminum-modified polysilicates or polyorthosilicic acid, bentonite, titanium dioxide or talc.
• Bentonite, talc, titanium dioxide or silica sol is particularly preferably used.
• additives based on inorganic minerals in amounts of 0.1 to 15% by weight, preferably 3 to 15% by weight, particularly preferably 5 to 13% by weight, based on the modified starch component, before the preparation of the modified starch components the starch digestion or during the starch digestion, preferably before the modifying reaction and the digestion with the cationic homo- or copolymer, results in a retention agent with improved effectiveness in the retention capacity of fillers and fines. ?
• the aqueous dispersion of the starch component which has not yet been digested and used for the modification preferably has a content of 0.5 to 20% by weight, preferably 0.5 to 10% by weight and particularly preferably 2.0 to 10% by weight of the starch component .
• the aqueous solution of the polyelectrolyte used for the modification has a content of 0.1 to 2.0% by weight, preferably 0.1 to 0.5% by weight and particularly preferably 0.1 to 0.3% by weight, of cationic homo - or copolymers.
• the weight ratio of starch component to cationic polyelectrolyte in the modification is in the range from 4: 1 to 25: 1, preferably in the range from 10: 1 to 25: 1 and particularly preferably in the range from 14: 1 to 20: 1.
• the retention agent according to the invention is added to the aqueous paper pulp dispersion in an amount of 0.1 to 10% by weight solids, preferably 0.5 to 5% by weight and particularly preferably 1.0 to 3% by weight, based on the dry matter or Pulp, added before the headbox of the paper machine, preferably as an aqueous solution with stirring. It is added to the aqueous dispersion, which already contains or has been added as fillers calcium carbonate, kaolin, aluminum silicate and oxide hydrates, satin white, talc, gypsum, barite, calcium silicate and lithopone, diatomaceous earth and synthetic, organic fillers from the recycling material.
• the retention agent according to the invention is advantageously added to the material dispersion in the machine chest, before the vertical classifier and before or after the material pump before the sheet formation.
• the retention agent according to the invention based on modified starch and inorganic additives achieves excellent retention of the fillers and surprisingly prevents the strength values from being impaired despite the increase in the filler and thus the ash content of the paper. This applies in particular to the use of paper pulp dispersions which contain or consist of portions of waste paper or wood pulps such as wood pulp and thermomechanical material (TMP).
• a mixed water-soluble cationic polymer provided with different amounts of bentonite or with the addition of talc and heated to a temperature of 95 to 100 ° C.
• no mineral was added. The mixture was held in this temperature range for 15 to 20 minutes, then cooled and used as a retention aid.
• Copolymers of trimethylammonium propylacrylamide chloride and acrylamide with a quaternized monomer content of 70% by weight were used as water-soluble cationic polymers.
• test sheets with a basis weight of approx. 100 g / m 2 were produced in the laboratory according to the Rapid Koethen method in accordance with DIN 54358 with the sheet forming device model 20-12 MC from Haage. The leaves were dried and overnight under normal conditions at 23 ° C and 50% rel. Humidity stored.
• the total retention gives the ratio of the amount of dry substance used for paper production to that remaining in the finished paper Amount of substance again. This can be determined by weighing the respective quantities of substance.
• the ash retention represents the ratio of the ash content of the (dry) amount of material used for paper production to the ash content of the finished paper. This is determined by determining the respective ash content.
• the fines retention shows the ratio of the fines content of the (dry) amount of paper used for paper production to the fines content of the finished paper.
• the corresponding fines content is determined using a Britt Dynamic Drainage Jar as follows:
• the coarse fraction corresponds to the amount of fiber that is on the filter.

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• Paper (AREA)
• Polysaccharides And Polysaccharide Derivatives (AREA)

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Publications (2)

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• 1998
  • 1998-07-17 DE DE19832241A patent/DE19832241A1/de not_active Withdrawn
• 1999
  • 1999-07-15 CA CA002336660A patent/CA2336660A1/fr not_active Abandoned
  • 1999-07-15 EP EP99938266A patent/EP1102894B1/fr not_active Expired - Lifetime
  • 1999-07-15 JP JP2000560317A patent/JP2002520510A/ja active Pending
  • 1999-07-15 DE DE59903194T patent/DE59903194D1/de not_active Expired - Fee Related
  • 1999-07-15 WO PCT/EP1999/005054 patent/WO2000004229A1/fr active IP Right Grant
  • 1999-07-15 CN CN99808782A patent/CN1309737A/zh active Pending
  • 1999-07-15 AT AT99938266T patent/ATE226663T1/de not_active IP Right Cessation
  • 1999-07-15 AU AU52835/99A patent/AU5283599A/en not_active Abandoned
  • 1999-07-15 BR BR9912832-2A patent/BR9912832A/pt not_active IP Right Cessation
• 2001
  • 2001-01-17 NO NO20010286A patent/NO20010286L/no unknown

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