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
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/03—Non-macromolecular organic compounds
  • D21H17/05—Non-macromolecular organic compounds containing elements other than carbon and hydrogen only
  • D21H17/17—Ketenes, e.g. ketene dimers
• • 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
  • D21H17/29—Starch cationic
• • 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
  • D21H17/71—Mixtures of material ; Pulp or paper comprising several different materials not incorporated by special processes
  • D21H17/72—Mixtures of material ; Pulp or paper comprising several different materials not incorporated by special processes of organic material
• • 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

Definitions

• the invention relates to paper sizing mixtures
• aqueous dispersions specified under (A) and (B) belong to the prior art.
• US Pat. No. 3,130,118 discloses aqueous alkyldiketene dispersions which can be obtained by dispersing the alkyldiketenes in water in the presence of cationic starch.
• Dispersions which are prepared in the presence of cationic condensates and optionally cationic starch are known, for example, from DE-A-30 00 502 and DE-A-33 16 179.
• Stabilized aqueous alkyldiketene dispersions are known from EP-B-0 437 764 which can contain up to 40% by weight of alkyldiketene in dispersed form and which, as stabilizer, contain long-chain fatty acid esters and / or urethanes in addition to cationic starch.
• Aqueous polymer dispersions which are a sizing agent for paper are described, for example, in the following references: JP-A-58/115 196, EP-B-0 257 412, EP-B-0 267 770, EP-B-0 051 144, EP-A-0 058 313 and EP-A-0 150 003. These references are referenced in the aforementioned WO-A-94/05855.
• paper sizing mixtures consist of emulsions of C 4 to C 2 o-alkyldiketenes and finely divided polymer dispersions containing copolymerized nitrogen-containing monomers and which consist of the abovementioned EP-B-0 051 144 are known.
• These sizing mixtures are prepared by combining a fatty alkyl diketene emulsion with an aqueous, finely divided polymer dispersion or are formed in the paper stock before sheet formation by adding the emulsified fatty alkyl diketene and the finely divided aqueous dispersion to the paper stock at the same time and mixing the system well. Mixtures which can only be obtained by stirring in cationic, finely divided aqueous polymer dispersions in fatty alkyl diketene dispersions are not sufficiently stable in storage.
• EP-B-0 353 212 discloses sizing agents in the form of aqueous emulsions which contain a hydrophobic cellulose-reactive sizing agent, e.g. Fatty alkyl diketene and a cationic starch with an amylopectin content of at least 85% and a degree of cationization (D.S.) from 0.045 to 0.40.
• the proportion of amylopectin in the cationic starch is preferably 98 to 100%.
• Starch which is preferably used is waxy corn starch.
• alkyldiketene dispersions which contain up to 30% by weight of ketene dimer.
• Other essential components of these alkyldiketene dispersions are cationic starch, preferably cationic waxy maize starches, aluminum sulfate, carboxylic acids with 1 to 10 carbon atoms, and sulfonates, such as lignosulfonic acid or condensation products of formaldehyde and naphthalenesulfonic acids.
• the object of the present invention is to provide an improved paper sizing agent containing fatty alkyl diketenes which, when used as a mass sizing agent, results in adequate instant sizing and does not impair the whiteness of the paper or in comparison the known mixtures has improved shear and storage stability.
• amylopectin content of the cationic starch of component (A) is at least 95%.
• the amylopectin content of the cationic starch is preferably 98 to 100%.
• Suitable starches of this type are preferably cationic waxy maize starches.
• the invention also relates to a process for producing paper size mixtures by mixing
• the invention also relates to the use of the paper sizing mixtures described above as mass and surface sizing agents for paper, cardboard and cardboard.
• component (A) For the preparation of component (A) one starts from C 1 -C 22 -alkyldiketenes or from mixtures of such alkyldiketenes.
• Alkyldiketenes are known and commercially available. They are produced, for example, from the corresponding carboxylic acid chlorides by splitting off hydrogen chloride with tertiary amines.
• Suitable fatty alkyldiketenes are, for example, tetradecyldiketene, hexadecyldiketene, octadecyldiketene, alkosyldiketene, docosyldiketene, palmityldiketene, stearyldiketene and behenyldiketene.
• diketenes with different alkyl groups for example stearylpalmithyldiketene, behenylstearyldiketene, behenyl oleyldiketene or palmithylbehenyldiketene.
• Stearyldiketene, palmithtyldiketene, behenyldiketene or mixtures of stearyldiketene and palmithyldiketene or mixtures of behenyldiketene and stearyldiketene are preferably used.
• the diketenes are present in the aqueous emulsions in concentrations of 5 to 60, preferably 10 to 40,% by weight.
• the alkyldiketenes are emulsified in water in the presence of cationic starch, which according to the invention has an amylopectin content of at least 95, preferably 98 to 100%.
• Such starches can be obtained, for example, by fractionation of conventional native starches or by breeding measures from plants which produce practically pure amylopectin starch, cf. Günther Tegge, Starch and Starch Derivatives, Hamburg, Bers-Verlag 1984, pages 157 to 160.
• Cationic starches with an amylopectin content of at least 95, preferably 98 to 100% by weight are available on the market.
• the amylopectin starches have a branched structure and have a high degree of polymerization.
• the molecular weights (number average) are, for example, 200 million to 400 million. For waxy maize starch with an amylopectin content of 99 to 100%, average molar masses (number average) of approx
• cationized starches are used whose amylopectin content is at least 95%.
• the degree of cationization of the starch is indicated with the aid of the degree of substitution (D.S.). This value reflects the number of cationic groups per monosaccharide unit in the cationic starch.
• the degree of substitution (D.S. value) of the cationic starches is, for example, 0.010 to 0.150. In most cases it is below 0.045, e.g. the cationic starches in question preferably have a degree of substitution (D.S.) of 0.020 to 0.040.
• the starch containing at least 95% by weight of amylopectin is cationized by introducing groups which contain tertiary or quaternary nitrogen atoms, e.g. by reacting the starches in question, in particular waxy corn starch, with dialkylaminoalkyl epoxides of the formula
• R 2 , R 3 and R 4 are alkyl, aryl, aralkyl or hydrogen
• R 1 is an alkylene group, for example Ci-C ß- alkylene.
• Examples of such compounds are 3-chloro-2-hydroxypropyltrimethylammonium chloride or glycidyltrimethylammonium chloride.
• wax potato starch In addition to the preferred waxy maize starch, wax potato starch, waxy wheat starch or mixtures of the starches mentioned are each suitable in cationized form.
• the cationic starches with amylopectin contents of at least 95% are contained in the aqueous alkyldiketene dispersion in an amount of 0.5 to 5, preferably 1 to 3,% by weight; the finely divided, aqueous dispersions of component (A) are usually so prepared that the starches containing at least 95% amylopectin are first converted into a water-soluble form. This can be done, for example, with the aid of oxidative or hydrolytic degradation in the presence of acids or simply by heating the cationic starches.
• the starch is preferably digested in a jet cooker at temperatures in the range from 100 to 150.degree.
• At least one C 1 -C 22 -alkyldiketene is then dispersed in the aqueous solution of the cationic starch with a minimum amylopectin content of at least 95% by weight at temperatures above 70 ° C., for example in the range from 70 to 85 ° C.
• the alkyldiketene dispersion is then cooled so that the alkyldiketenes are in solid form.
• Finely divided aqueous alkyldiketene dispersions having an average particle diameter of, for example, 0.5 to 2.5, preferably 0.8 to 1.5, are obtained.
• the dispersion of the alkyldiketenes in water can optionally additionally in the presence of lignosulfonic acid, condensates of formaldehyde and naphthalene sulfonic acids, polymers containing styrene sulfonic acid groups or the alkali metal and / or ammonium salts of the compounds containing said sulfonic acid groups.
• lignosulfonic acid condensates of formaldehyde and naphthalene sulfonic acids, polymers containing styrene sulfonic acid groups or the alkali metal and / or ammonium salts of the compounds containing said sulfonic acid groups.
• lignosulfonic acid condensates of formaldehyde and naphthalene sulfonic acids
• polymers containing styrene sulfonic acid groups or the alkali metal and / or ammonium salts of the compounds containing said
• alkyldiketene emulsions In the preparation of the alkyldiketene emulsions it is possible to use, in addition to the cationic wax starches, other customary protective colloids which have hitherto been used in the preparation of alkyldiketene emulsions, e.g. Water-soluble cellulose ethers, polyacrylamides, polyvinyl alcohols, polyvinyl pyrrolidones, polyamides, polyamidoamines and mixtures of the compounds mentioned.
• Component (A) may optionally contain further substances which are common in alkyldiketene dispersions, e.g. Ci to Cio carboxylic acids, e.g. Formic acid, acetic acid or propionic acid.
• the acids are used in amounts of 0.01 to 1% by weight.
• the alkyldiketene dispersions can optionally also contain conventional biocides, which can be used in amounts of up to 1% by weight.
• Component (B) of the paper sizing mixtures according to the invention consists of finely divided, aqueous polymer dispersions which are a sizing agent for paper.
• Such polymer dispersions are known, for example, from EP-B-0 051 144, EP-B-0 257 412, EP-B-0 276 770, EP-B-0 058 313 and EP-B-0 150 003 .
• Such polymer dispersions which act as paper sizing agents are obtainable, for example, by mixing 1 to 32 parts by weight of a mixture
• di-Ci to C 4 -alkylamino-C2 to C-alkyl (meth) acrylates which may optionally be protonated or quaternized
• nonionic, hydrophobic, ethylenically unsaturated monomers in the case of these monomers, if they are polymerized on their own, form hydrophobic polymers and, if appropriate
• a solution copolymer is first prepared in which the monomers of groups (1) and (2) and optionally (3) are copolymerized in a water-miscible organic solvent.
• Suitable solvents are, for example, C 1 -C 3 -carboxylic acids, such as formic acid, acetic acid and propionic acid, or C 1 -C 4 -alcohols, such as methanol, ethanol, n-propanol or isopropanol, and ketones such as acetone.
• the group (1) monomers used are preferably dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminopropyl methacrylate and dimethylaminopropylacrylate.
• the monomers in group (1) are preferably used in protonated or quaternized form. Suitable quaternizing agents are, for example, methyl chloride, dimethyl sulfate or benzyl chloride.
• the group (2) monomers used are nonionic, hydrophobic, ethylenically unsaturated compounds which, when polymerized on their own, form hydrophobic polymers. These include, for example, styrene, methylstyrene, Ci bis
• Ci ⁇ -alkyl esters of acrylic acid or methacrylic acid for example methyl acrylate, ethyl acrylate, N-propyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate and isobutyl acrylate as well as isobutyl methacrylate, n-butyl methacrylate and tert-butyl methacrylate.
• Acrylonitrile, methacrylonitrile, vinyl acetate, vinyl propionate and vinyl butyrate are also suitable.
• Mixtures of the group 2 monomers can also be used in the copolymerization, for example mixtures of styrene and isobutyl acrylate.
• the solution copolymers used as emulsifiers can optionally also contain copolymerized monomers of group (3), for example monoethylenically unsaturated C 3 - to Cs-carboxylic acids or their anhydrides, for example acrylic acid, methacrylic acid, itaconic acid, maleic acid, maleic acid anhydride or itaconic anhydride.
• the molar ratio of (1): (2): (.3) is 1: 2.5 to 10: 0 to 1.5.
• the copolymer solutions obtained in this way are diluted with water and in this form serve as a protective colloid for the polymerization of the above-mentioned monomer mixtures of components (a) and (b) and optionally (c).
• Suitable monomers of group (a) are styrene, acrylonitrile, methacrylonitrile or mixtures of styrene and acrylonitrile or of styrene and methacrylonitrile.
• the group (b) monomers used are acrylic acid and / or methacrylic acid esters of C 1 -C 4 -alcohols and / or vinyl esters of saturated C 2 -C 4 -carboxylic acids. This group of monomers corresponds to the monomers of group (2), which has already been described above.
• Preferably used as the monomer of group (b) are butyl acrylate and butyl methacrylate, for example isobutyl acrylate, n-butyl acrylate and isobutyl methacrylate.
• Monomers of group (c) are, for example, C 3 - to C 5 -monoethylenically unsaturated carboxylic acids, acrylamidomethylpropanesulfonic acid, sodium vinyl sulfonate, vinyl imidazole, N-vinyl formamide, acrylamide, methacrylamide and N-vinyl imidazoline.
• 1 to 32 parts by weight of a monomer mixture of components (a) to (c) are used per 1 part by weight of the copolymer.
• the monomers of components (a) and (b) can be copolymerized in any ratio, for example in the molar ratio 0.1: 1 to 1: 0.1.
• the monomers of group (c) are used to modify the properties of the copolymers.
• the finely divided, aqueous dispersions described as sizing agents for paper which are known from EP-0 257 412 and EP-B-0 276 770, are preferably used. These dispersions are obtained by copolymerizing
• These starches have been subjected to oxidative, thermal, acidolytic or enzymatic degradation. All native starches can be used for this degradation, for example starches from potatoes, wheat, rice, tapioca and corn, and starches with amylopectin contents of at least 95, preferably 98 to 100% by weight, for example waxy corn starch, waxy potato starch, wax white Zen starch or mixtures of the starches mentioned.
• chemically modified starches can be used, such as starches containing hydroxyethyl, hydroxypropyl or quaternized aminoalkyl groups with viscosities in the range given above.
• Oxidatively degraded potato starches, cationized, degraded potato starches or hydroxyethyl starch are particularly suitable.
• the mixture of size-acting copolymer dispersion and an undigested starch is preferably stirred at 85 ° C. for at least 10 minutes. This unlocks the strength.
• the degraded starches act as emulsifiers in the copolymerization of the monomers (a) to (c) in an aqueous medium in the manner of an emulsion polymerization.
• the monomers are copolymerized in an aqueous solution containing 1 to 21, preferably 3 to
• 15 contains 15% by weight of broken down starch.
• 10 to 140 preferably 40 to 100 parts by weight of the monomer mixture of (a) and (b) and optionally (c) are polymerized in 100 parts by weight of such a solution.
• the diameter of the dispersed polymer particles is 50 to 350, preferably 100 to 250 nm.
• group (b) are also vinyl esters of C 2 - to C 4 -saturated carboxylic acids.
• Suitable monomers of group (c) are, for example, acrylamide, methacrylamide, stearyl acrylate, stearyl methacrylate, palmityl acrylate, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid,
• the paper sizing mixtures according to the invention are produced by known processes, cf. DE-A-32 35 529 and W0-A-94/05855.
• the procedure is, for example, that (A) finely divided, aqueous dispersions of C 14 -C 22 -alkyldiketenes which are dispersed in water by dispersing the alkyldiketenes
• the starches having been converted into a water-soluble form and emulsifying finely divided, aqueous polymer dispersions which are a sizing agent for paper at temperatures of at least 70 ° C.
• the emulsification is preferably carried out here under the action of high shear forces, e.g. in so-
• the resulting emulsions are preferably rapidly cooled to room temperature.
• the resulting dispersions of paper size mixtures have one pH in the range from 2 to 4, preferably the pH is 3.
• the paper sizing mixtures can also be prepared by mixing components (A) and (B), for example in a stirred kettle, and adding this mixture - 5 if homogenized under the action of high shear forces at temperatures of, for example, 20 to 70 ° C.
• the paper sizing mixtures according to the invention contain, for example, 1 to 55, preferably 10 to 30% by weight of alkyldiketenes and 1 to 60, preferably 3 to 25% by weight of finely divided polymer dispersions, 10 in each case based on the solids.
• component (B) 15 parts of polymer dispersion of component (B), based on the solids.
• component (B) 15 parts of polymer dispersion of component (B), based on the solids.
• 20 polymer dispersions is, for example, 50 to 400, preferably 100 to 250 nm.
• the sizing agent mixtures according to the invention are stable on storage, i.e. they do not tend to separate and do not become solid. They also have a very low viscosity (for example after storage of
• the viscosities are below 100 mPas, measured in a Brookfield viscometer at 100 rpm, and a temperature of 25 ° C with spindle No. 1) and are also characterized by a high stability against the action of Shear forces, such as those used for pumping
• the sizing mixtures are used as mass and surface sizing agents for paper, cardboard and cardboard. Use as a mass sizing agent in the manufacture of paper is preferred.
• Starch A is a degraded cationic potato starch with a viscosity ⁇ i of 0.47 dl / g, a degree of substitution of 0.015-COOH and 0.027 N mol / mol glucose units and a solids content of 83%.
• Starch B is a degraded, cationic potato starch with a viscosity ⁇ of 1.16, a degree of substitution of 0.07 N mol / mol of glucose units and a solids content of 83%.
• the temperature of the reaction mixture is kept at 85 ° C.
• a dispersion with a solids content of 41.0% and a particle diameter (without starch shell) of 100-150 nm is obtained.
• the dispersion is diluted to a solids content of 33% by adding water.
• a mixture of 20 parts (1.92 mol) of styrene, 7 parts (0.41 mol) of dimethylaminopropylmethacryla id. 3.5 parts of 45 (0.486 mol) of acrylic acid and 10 parts of acetic acid were pumped into a kettle heated to 90 ° C. within 1 hour using a pump. Simultaneously and also within 1 hour 2 parts of azoisobutyronitrile and 10 parts of acetic acid were added using another metering device. The mixture was heated to a temperature of 90 ° C. for 30 minutes and then dissolved in 180 parts of water.
• the initially coarse suspension is passed through a homogenizer twice at a temperature of 85 ° C. and a pressure of 150 bar and then rapidly cooled to room temperature.
• a commercial cationic waxy maize starch (D.S. 0.04, amylopectin content 100%) is soaked in water in such an amount.
• the mixture is first treated with an Ultraturrax and then twice in a homogenizer under a pressure of 150 bar and a temperature of 85 ° C. and then rapidly cooled to room temperature.
• a 5.13% strength aqueous suspension of a commercially available cationic starch (D.S. 0.02, amylopectin content 70%) is first prepared, and 50 parts of the suspension were added to 50 parts of this suspension
• Polymer dispersion 1 and the starch by heating for 10 minutes in the mixture with the polymer dispersion 1 at a temperature of 85 ° C.
• the properties of the dispersion are given in Table 1.
• Example 1 was repeated with the changes that a 5.13% strength aqueous suspension of a commercially available cationic starch (degree of substitution 0.02, amylopectin content 75%) was prepared, mixed with 50 parts of polymer dispersion 2 and the
• the shear stability of the sizing agent mixtures described in the examples and comparative examples was determined by pumping the mixtures through a 400 ⁇ m filter using a centrifugal pump. 500 ml of the paper size mixture was used in each case and the temperature of the mixture was kept at 25 ° C. during the test. Table 2 shows the times after which the filter became blocked or the test was terminated.

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• 1995
  • 1995-04-03 DE DE19512399A patent/DE19512399A1/de not_active Withdrawn
• 1996
  • 1996-03-26 WO PCT/EP1996/001315 patent/WO1996031650A1/fr active IP Right Grant
  • 1996-03-26 EP EP96908139A patent/EP0819193B1/fr not_active Expired - Lifetime
  • 1996-03-26 JP JP52994296A patent/JP3805367B2/ja not_active Expired - Lifetime
  • 1996-03-26 DK DK96908139T patent/DK0819193T3/da active
  • 1996-03-26 AT AT96908139T patent/ATE180526T1/de active
  • 1996-03-26 ES ES96908139T patent/ES2133193T3/es not_active Expired - Lifetime
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