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
  • D21H21/14—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 characterised by function or properties in or on the paper
  • D21H21/16—Sizing or water-repelling agents
• • 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
  • D21H19/00—Coated paper; Coating material
  • D21H19/10—Coatings without pigments
  • D21H19/14—Coatings without pigments applied in a form other than the aqueous solution defined in group D21H19/12
  • D21H19/20—Coatings without pigments applied in a form other than the aqueous solution defined in group D21H19/12 comprising macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• • 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
  • D21H17/41—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing ionic groups
  • D21H17/44—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing ionic groups cationic

Definitions

• the present invention relates to a process for the surface sizing of paper, cardboard and cardboard.
• Paper is a cellulose-containing fiber composite having a typical polar, highly hydrophilic character, i. it is easily wettable and swellable by aqueous systems. This results in excessive and uncontrolled penetration of water and other liquids (e.g., ink, inks) into the nonwoven fabric during writing, printing, and paper processing.
• the resulting problems are i.a. a weakening of internal fiber bonding force, deterioration of mechanical properties, reduction of dimensional stability and very poor writing and printability.
• sizing agents are used, which counteract by partial hydrophobing the behavior described above.
• These aids can be added to the aqueous cellulose pulp (engine sizing) as well as by a surface treatment of the already formed paper web by means of a corresponding application unit such as size press, film press, coater, etc. (surface sizing) are applied.
• a corresponding application unit such as size press, film press, coater, etc.
• the application unit is usually applied with an aqueous size liquor preparation consisting of a (degraded) starch and a surface sizing agent and, in addition, further additives such as e.g. Polyvinyl alcohol, dyes, pigments, salts and optical brightener may contain.
• a starch e.g. Potato starch, corn starch, wheat starch or tapioca starch in question, by means of
• Papermakers be known methods pretreated before use can. These include oxidative, thermochemical or enzymatic
• the starches may also be chemically modified, e.g. by cationization or alkylation.
• the surface sizing agents used in the prior art are predominantly polymers which can be present both in solution and in dispersed form (emulsion polymers). Common are e.g. modified copolymers of styrene and maleic anhydride, copolymers of methacrylate and acrylate monomers, copolymers of styrene with acrylate / methacrylate monomers, polyurethane dispersions or copolymers and graft polymers of acrylonitrile. All of these sizing agents are inherent in that they contain a hydrophilic and a hydrophobic part of the molecule, whereby the charge of the polymer is also defined by the hydrophilic part. It is possible to use anionic, amphoteric, cationic and, in principle, nonionic polymers. By way of example, EP 406 461, EP 357 866, EP 735 065, EP 701 019 and EP 320 609 may be mentioned.
• Typical packaging papers are z-B. Kraftliner, Testliner and
• Corrugating medium or fluting which are required for the production of corrugated cardboard packaging (corrugated base paper).
• Fresh raw materials (unbleached sulphate pulp) and preferably waste paper are used as raw materials for production.
• the Papers and boxes can be gray, brown or with a light topcoat (white covered liner).
• As other packaging papers are various other types of paper and board for a variety of
• Graph paper is the general term for types of paper used for writing, painting and printing. Typical examples are copy paper, offset paper, exercise books, writing pads, calendars, postcards, watercolor paper, newspapers, magazine paper, advertising supplements, catalogs, book printing paper and the like. As raw materials one uses for this wood pulp, thermomechanical pulp, reclaimed waste paper and others. To a large extent, bleached pulp is used.
• the papers and cartons may be coated on one or both sides, and are predominantly white, but may also be e.g. be gray or colored. The white background is preferred to enhance the overall appearance and print and image contrast.
• optical brighteners These are usually di-, tetra- or Hexasulfonklarivate the stilbene. These come mainly in the surface but also in the wet area
• anionic and cationic chemical compounds There is basically an incompatibility or at least negative mutual influence of anionic and cationic chemical compounds.
• the combination of the products leads to coacervation, generates harmful precipitates or the components interfere with each other and their effectiveness. Therefore, according to the state of the art for surface sizing in combination with anionic optical brighteners exclusively anionic, amphoteric or weakly cationic sizing agents can be used. These are all significantly less effective than more cationic sizing agents.
• Suitable cationic polymer dispersions according to the invention are the cationic polymer dispersions known for surface sizing.
• the polymers are preferably emulsion polymers.
• Preferred monomers are ethylenically unsaturated compounds, for example styrene and nitrogen-containing acrylate or methacrylate monomers, for example aminalkylated acrylic and / or methacrylamides.
• they are styrene-acrylate copolymer dispersions.
• the acrylate used is preferably acrylic esters, such as methyl, ethyl, propyl and butyl acrylates, particularly preferably butyl, especially tert-butyl acrylate.
• the copolymer contains cationized acrylamide or methacrylamide groups, in particular di-alkylaminoalkyl (meth) acrylamide groups.
• the alkylamino groups are preferably methyl groups.
• Solids content is typically 25 to 35%. Particularly suitable are e.g. the commercially available products Perglutin ® K600 and in particular
• alkyl ketene dimer dispersions and emulsions are suitable. These have a lactone ring with long-chain alkyl radicals, preferably fatty acids or fatty acid derivatives.
• the AKD dispersions available on the market differ primarily by the fatty acids used in the preparation and thus by different melting points and differentiated chain lengths and branching of the alkyl groups. Widely used is a mixture of C16 / C18 alkyl ketene dimers with a solidification point of about 40-50 0 C. At higher temperatures, melting AKD is based on higher fatty acids such as stearic acid (C18) or
• C22 Behenic acid (C22), manufactured and used for specialty papers or at higher pulp temperatures.
• the melting point of C18-AKD is in the range 55-60 0 C, that of C22-AKD at about 58-65 0 C.
• Liquid AKD is produced on the basis of oleic acid or isostearic acid. It has the advantage of producing no waxy deposits and less slipperiness on the
• liquid AKD is a reduced sizing efficiency over products with linear alkyl groups.
• the solids content is typically 10 to 25%.
• the dispersion or emulsion may also contain other additives in a manner known per se, for example dispersants and / or stabilizers. Preference is given to cationic or amphoteric dispersants, such as eg cationic starch, polyamidoamine resins,
• Alkylketene dimer dispersions have long been used in papermaking as engine size. They are also already used in surface sizing and are combined there with amphoteric or weakly cationic polymers. Many attempts to use them in the surface in pure form failed, mostly because of difficult to control sizing, long maturation time to achieve final sizing, high slipperiness of the paper, deposits due to hydrolysis and the like. Problems. Surprisingly, these negative properties of the AKD can be significantly reduced in the application according to the invention, so that their supporting sizing effect can additionally be utilized.
• a mixture is prepared from the cationic polymer dispersion and the AKD dispersion.
• the storage stability of the AKD is also significantly increased in the mixture. This was usually limited to 4 to 10 weeks and improved to 8 to 14 weeks.
• Mixing ratio of cationic polymer dispersion to AKD dispersion based on the weight, preferably from 90:10 to 50:50, particularly preferably from 85:15 to 70:30 and in particular about 80:20.
• the size liquor according to the invention also contains starch and an anionic, optical brightener and may comprise further additives known per se. To name here are in particular
• sulfonic acid-bearing derivatives of stilbene are suitable. Preference is given to di-, tetra- or hexasulfonated stilbene derivatives, very particular preference is given to di-, tetra- or hexasulfonated diaminostilbenes, such as e.g. 4,4'-diamino-2,2'-stilbene disulfonic acid.
• the process for surface sizing according to the invention is characterized by the use of an anionic, optical brightener together with a cationic polymer dispersion as sizing, which by the
• the size liquor can be prepared by spraying or by means of the known application aggregates, such as, for example, Size press, film press, Speedsizer, as well as online or offline with a coater.
• a cationic polymer dispersion tradename Perglutin K 532, was blended with a cationic alkyl ketene dimer emulsion in various proportions
• the glue liquor contained 7.5% each of an enzymatically degraded corn starch and had a viscosity of 33 mPas at 60 0 C.
• the pH of the starch liquor without Leimungsffenzusatz was 6.6.
• Commercial brighteners used were commercially available products, one from the tetrasulfonated group and one from the hexasulfonated diaminostilbene derivatives group, in a very high concentration of 25 g / l.
• the sizing agents used were the cationic polymer dispersion in pure form and the mixtures with AKD a) to d) in a concentration of 7 g / l in the sizing liquor.
• the paper was dried after the modification with the glue liquor 2 min at 100 0 C in a drum drier and then for another 10 min. post-treated at 105 ° C.
• the Cobb value is a measure of the water absorption of a paper. The lower the value, the better the sizing.
• the determination of the Cobb Value according to DIN 20535 (DIN EN 20535).
• the whiteness was determined using an Elrepho 2000 from Datacolor according to DIN 53145/2.
• the calculation of the wet pick-NA in [%] was carried out from wet weight (m f) and dry weight (m ⁇ utr o) of the respective paper corresponding to the formula
• NA (m f - niutro) / m o utr o * 100
• miutro dry weight of the sample before passing the fleece [g].
• the wet pick-up was 54% for all papers.
• anionic brightener on the sizing effect of the cationic polymer dispersion already decreases significantly with an addition of 10% of the AKD dispersion. A loss of whiteness does not occur.
• a cationic polymer dispersion trade name Perglutin K 532, was mixed with a cationic alkyl ketene dimer emulsion in the ratio 80:20 by stirring. This mixture according to the invention was used with the cationic
• Perglutin A 288 and the cationic, promoter-free alkyl ketene dimer emulsion compared.
• an unsized raw paper with a basis weight of 100 g / m 2 prepared from 100% eucalyptus sulfate pulp and 15% precipitated calcium carbonate (PCC) in a laboratory size press from Einlehner
• the glue liquor contained 7.5% of an enzymatically degraded corn starch and had a viscosity of 34 mPas at 60 0 C.
• the pH Value of the starch liquor without addition of sizing agent was 6.9.
• Brightener was a commercial product from the group of tetrasulfon notorious Diaminostilbenderivate used in a very high concentration of 25 g / l.
• the sizing agents used were the above-mentioned products in a concentration of 7 g / l in the sizing liquor.
• the cationic alkyl ketene dimer emulsion was added at a concentration of 1.4 g / l to the size liquor.
• the wet pick-up was 47% for all papers.
• the paper was dried after modification with the glue liquor for 2 min at 100 ° C in a roller dryer and then 10 min. post-treated at 105 ° C.
• a cationic polymer dispersion trade name Perglutin K 532, was mixed with a cationic alkyl ketene dimer emulsion in the ratio 80:20 by stirring. With this mixture, the cationic polymer dispersion
• the products mentioned were used in pure form in a concentration of 12 g / l in the sizing liquor.
• the wet pick-up was 75% for all papers.
• the paper was dried after the modification with the glue liquor 2 min at 100 0 C in a drum drier and then for a further 10 min post-treated at 105 0 C.
• a cationic polymer dispersion trade name Perglutin K 532, was mixed with a cationic alkyl ketene dimer emulsion in the ratio 80:20 by stirring. With this mixture, the cationic polymer dispersion
• the glue liquor contained 7.5% of an enzymatically degraded Corn starch and had a viscosity of 33 mPas at 60 0 C.
• the pH of the starch liquor without sizing agent addition was 6.8.
• the optical brightener used was a commercially available product from the group of hexasulfonated diaminostilbene derivatives in a very high concentration of 25 g / l.
• the sizing agents used were the above-mentioned products in a concentration of 7 g / l in the sizing liquor.
• the wet pick-up was 60%.
• the paper was dried after the modification with the glue liquor 2 min at 100 0 C in a drum drier and then for another 10 min. post-treated at 105 ° C.

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• Chemical Kinetics & Catalysis (AREA)
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• 2009
  • 2009-08-06 DE DE102009036344A patent/DE102009036344A1/de not_active Ceased
• 2010
  • 2010-07-17 EP EP10734702A patent/EP2462282A1/de not_active Withdrawn
  • 2010-07-17 BR BR112012002516A patent/BR112012002516A2/pt not_active IP Right Cessation
  • 2010-07-17 US US13/386,992 patent/US20120171384A1/en not_active Abandoned
  • 2010-07-17 WO PCT/EP2010/004372 patent/WO2011015280A1/de active Application Filing
  • 2010-07-17 CN CN201080034624.5A patent/CN102549216B/zh not_active Expired - Fee Related
  • 2010-07-17 IN IN365DEN2012 patent/IN2012DN00365A/en unknown

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