WO1997013033A1 - Process for producing paper with a dry-strength and wet-strength finish - Google Patents

Process for producing paper with a dry-strength and wet-strength finish Download PDF

Info

Publication number
WO1997013033A1
WO1997013033A1 PCT/EP1996/004202 EP9604202W WO9713033A1 WO 1997013033 A1 WO1997013033 A1 WO 1997013033A1 EP 9604202 W EP9604202 W EP 9604202W WO 9713033 A1 WO9713033 A1 WO 9713033A1
Authority
WO
WIPO (PCT)
Prior art keywords
paper
dry
polyisocyanates
strength
polymers
Prior art date
Application number
PCT/EP1996/004202
Other languages
German (de)
French (fr)
Inventor
Friedrich Linhart
Werner Auhorn
Karl Häberle
Rudolf Schuhmacher
Rainer Dyllick-Brenzinger
Original Assignee
Basf Aktiengesellschaft
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Basf Aktiengesellschaft filed Critical Basf Aktiengesellschaft
Publication of WO1997013033A1 publication Critical patent/WO1997013033A1/en

Links

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
    • D21H17/20—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
    • D21H17/45—Nitrogen-containing groups
    • 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
    • D21H17/07—Nitrogen-containing compounds
    • D21H17/08—Isocyanates
    • 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
    • D21H21/18—Reinforcing agents

Definitions

  • the invention relates to a process for producing dry-strength and wet-strength paper by adding hydrophilically modified polyisocyanates and cationic polymers to the pulp and dewatering the pulp with sheet formation or by treating the surface of paper with hydrophilically modified polyisocyanates and cationic polymers.
  • US Pat. No. 4,421,602 discloses partially hydrolyzed, water-soluble polymers of N-vinylformamide which contain N-vinylformamide units and vinylamine units. The polymers are used as agents for increasing flocculation, retention and dewatering speed in the manufacture of paper.
  • copolymers containing vinylamine units which can be used as dry and wet strength agents in the production of paper are known, for example, from EP-B-0 251 182.
  • EP-A-0 564 912 discloses the use of water-dispersible polyisocyanates for the wet-strength finishing of paper.
  • the advantage of these wet strength agents is that they have no organically bound chlorine.
  • the water-dispersible polyisocyanates can also be used in a mixture of conventional retention or wet strength agents.
  • Polyamidoamine-epichlorohydrin resins are mentioned by way of example. However, such resins contain organically bound chlorine.
  • EP-A-0 582 166 discloses a process for the production of dry-strength and wet-strength finished and / or sized cellulose-containing material, the cellulose-containing material being treated with a water-dispersible polyisocyanate mixture which contains tertiary amino and / or ammonium groups becomes.
  • the water-dispersible polyisocyanate mixtures can also be used in combination with reactive sizing agents such as alkyldiketenes or alkenyl succinic anhydrides.
  • the polyisocyanate mixtures can optionally be used with cationic auxiliaries such as retention agents, fixing agents, dry strength agents and wet strength agents, for example polyamines, polyethyleneimines, polyamidoamines and polyacrylamides.
  • cationic polycondensates composed of polyamines and alkylene dihalides, preferably dichloroethane.
  • the invention has for its object to increase the effectiveness of dry and wet strength agents that do not contain organically bound chlorine.
  • the object is achieved according to the invention with a process for the production of dry-strength and wet-strength finished paper by adding hydrophilically modified polyisocyanates and cationic polymers to the paper stock and dewatering the paper stock with sheet formation or by treating the surface of paper with hydrophilically modified polyisocyanates and cat - Ionic polymers, if one uses polymers containing vinylamine units as cationic polymers.
  • hydrophilically modified polyisocyanates which are also referred to as water-dispersible polyisocyanates, are in the form of aqueous dispersions which are essentially free of organic solvents and other emulsifiers.
  • hydrophilically modified polyisocyanates used according to the invention are customary diisocyanates and / or usual higher-functional polyisocyanates with an average NCO functionality of 2.0 to 4.5. These components can be present alone or in a mixture.
  • customary diisocyanates are aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate (1,6-diisocyanate hexane), octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, trimethylhexane diisocyanate, 1,4-diisocyanate, or tetramate diisocyanate, or tetramate diisocyanate, or tetramate diisocyanate, or tetramate diisocyanate such as 1,3-diisocyanate 1,2-diisocyanatocyclohexane, 4,4'-di (isocyanatocyclohexyl) methane, 1-isocyanato-3,3, 5-trimethyl-5- (isoeyanatomethyl) cyclohexane (isophorone di
  • aliphatic diisocyanates in particular hexamethylene diisocyanate and isophorone diisocyanate, are preferred.
  • suitable higher-functional polyisocyanates are triisocyanates such as 2,4,6-triisocyanatotoluene or 2,4,4'-triisocyanatodiphenyl ether or the mixtures of di-, tri- and higher polyisocyanates obtained by phosgenation of the corresponding aniline / formaldehyde Condensates are obtained and represent polyphenyl polyisocyanates having methylene bridges.
  • the corresponding isocyanato-isocyanates based on hexamethylene diisocyanate and isophorone diisocyanate are particularly preferred.
  • the present isocyanurates are, in particular, simple tris-isocyanatoalkyl or triisocyanatocycloalkyl isocyanurates, which are cyclic trimers of the diisocyanates, or mixtures with their higher homologues having more than one isocyanurate ring.
  • the isocyanato-isocyanurates generally have an NCO content of 10 to 30% by weight, in particular 15 to 25% by weight, and an average NCO functionality of 2.6 to 4.5.
  • uretdione diisocyanates with aliphatic and / or cycloaliphatic bound isocyanate groups, preferably derived from hexamethylene diisocyanate or isophorone diisocyanate.
  • Uretdione diisocyanates are cyclic dimerization products of diisocyanates.
  • polyisocyanates containing biuret groups with aliphatically bound isocyanate groups in particular tris (6-isocyanato-hexyDbiuret or its mixtures with its higher homologues.
  • These polyisocyanates containing biuret groups generally have an NCO content of 18 to 25% by weight and a average NCO functionality from 3 to 4.5.
  • Polyisocyanates containing urethane and / or allophanate groups with aliphatically or cycloaliphatically bound isocyanate groups such as, for example, by reacting excess amounts of hexamethylene diisocyanate or isophorone diisocyanate with simple polyhydric alcohols such as trimethylolpropane, glycerol, 1, 2-dihydroxypropane or their mixture can be obtained.
  • These polyisocyanates containing urethane and / or allophanate groups generally have an NCO content of 12 to 20% by weight and an average NCO functionality of 2.5 to 3.
  • Polyisocyanates containing oxadiazinetrione groups preferably derived from hexamethylene diisocyanate or isophorone diisocyanate.
  • Such polyisocyanates containing oxadiazinetrione groups can be prepared from diisocyanate and carbon dioxide.
  • Aliphatic diisocyanates and aliphatic higher-functional polyisocyanates are particularly preferred for the use according to the invention.
  • the described diisocyanates and / or higher functionalized polyisocyanates are converted to NCO-reactive compounds for conversion into non-ionically hydrophilically modified polyisocyanates, which are particularly preferred for the use according to the invention, and the hydrophilic structural elements with non-ionic groups or with polar Contain groups that cannot be converted into ion groups.
  • the diisocyanate or polyisocyanate is present in a stoichiometric excess so that the resulting hydrophilically modified polyisocyanate still has free NCO groups.
  • Hydroxyl group-terminated polyethers of the general formula I in particular come as such NCO-reactive compounds with hydrophilicizing structural elements
  • R 1 represents Cx to C 20 alkyl, in particular C 1 to C 4 alkyl, or C 2 to C 20 alkenyl, cyclopentyl, cyclohexyl, glycidyl, oxethyl, phenyl, tolyl, benzyl, furfuryl or tetrahydrofurfuryl, X denotes sulfur or in particular oxygen,
  • n stands for a number from 5 to 120, in particular 10 to 25,
  • Ci- to C 4 alkanol started ethylene oxide or propylene oxide polyethers having average molecular weights of from 250 to 7000, in particular from 450 to 1,500.
  • diisocyanates and / or more functionalized polyisocyanates it is also possible first of all by reaction with a deficit of hydroxyl-terminated polyesters, on other hydroxyl-terminated polyethers or on polyols, e.g. Generate ethylene glycol, trimethylolpropane or butanediol, prepolymers and then implement these prepolymers either subsequently or simultaneously with the polyethers I in deficit to the hydrophilically modified polyisocyanates with free NCO groups.
  • nonionically hydrophilically modified polyisocyanates from diisocyanate or polyisocyanate and polyalkylene glycols of the formula HO— (AO) n —H, in which A and n have the meanings given above. Both terminal OH groups of the polyalkylene glycol react with isocyanate.
  • non-ionically hydrophilically modified polyisocyanates are in the documents DE-A 24 47 135, DE-A 26 10 552, DE-A 29 08 844, EP-A 0 13 112, EP-A 019 844, DE-A 40 36 927, DE-A 41 36 618, EP-B 206 059, EP-A 464 781 and EP-A 516 361.
  • the described diisocyanates and / or higher functionalized polyisocyanates are converted into anionically hydrophilically modified polyisocyanates with NCO-reactive compounds which contain hydrophilic anionic groups, in particular acid groups such as carboxyl groups, sulfonic acid groups or phosphonic acid groups.
  • the diisocyanate or polyisocyanate is present in a stoichiometric excess so that the resulting hydrophilically modified polyisocyanate still has free NCO groups.
  • Such NCO-reactive compounds with anionic groups are, above all, hydroxyearonic acids such as 2-hydroxyacetic acid, 3-hydroxypropionic acid, 4-hydroxybutyric acid or hydroxypivalic acid and 2,2-bis- and 2,2,2-tris (hydroxymethyl) alkanoic acids, for example 2,2-bis (hydroxymethyl) acetic acid, 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (hydroxymethyl) butyric acid or 2,2,2-tris (hydroxymethyl) acetic acid.
  • the carboxyl groups can be partially or completely neutralized by a base in order to be present in a water-soluble or water-dispersible form.
  • the base used here is preferably a tertiary amine, which is known to be inert to isocyanate.
  • the described diisocyanates and / or more highly functionalized polyisocyanates can also be reacted with a mixture of nonionically hydrophilically modifying and anionically hydrophobically modifying compounds which are added in succession or simultaneously, for example with a deficiency of the polyethers I and the described hydroxyearonic acids .
  • anionically hydrophilically modified polyisocyanates are described in more detail in documents DE-A-40 01 783, DE-A-41 13 160 and DE-A-41 42 275.
  • the described diisocyanates and / or more highly functionalized polyisocyanates are converted into cationically hydrophilically modified polyisocyanates with NCO-reactive compounds which contain chemically incorporated alkylatable or protonatable functions with the formation of a cationic center.
  • NCO-reactive compounds which contain chemically incorporated alkylatable or protonatable functions with the formation of a cationic center.
  • such functions are tertiary nitrogen atoms, which are known to be inert to isocyanate and can be easily quaternized or protonated.
  • NCO-reactive compounds with tertiary nitrogen atoms are preferably amino alcohols of the general formula II
  • R 2 and R 3 are linear or branched C 1 to C 20 alkyl, in particular C 1 to C 5 alkyl, or together with the N atom form a five- or six-membered ring which is also an O atom or a tertiary one N atom can contain, in particular a piperidine, morpholine, piperazine, pyrrolidine, oxazoline or dihydrooxazine ring, where the radicals R 2 and R 3 can additionally carry hydroxyl groups, in particular in each case one hydroxyl group, and
  • R 4 denotes a C 2 - to Cio-alkylene group, in particular a C 2 - to C ⁇ -alkylene group, which can be linear or branched,
  • Particularly suitable amino alcohols II are N-methyldiethanolamine, N-methyldi (iso) propanolamine, N-butyldiethanolamine, N-butyldi (iso) propanolamine, N-stearyldiethanolamine, N-stearyldi (iso) propanolamine, N, N -Dimethylethanolamine, N, N-dimethyl (iso) propanolamine, N, N-diethylethanolamine, N, N-diethyl (iso) propanolamine, N, N-dibutylethanolamine, N, N-dibutyl (iso) propanolamine , Triethanolamine, tri (iso) propanolamine, N- (2-hydroxyethyl) morpholine, N- (2-hydroxypropyl) morpholine, N- (2-hydroxyethyl) piperidine, N- (2-hydroxypropyl) piperidine, N-methyl-N '- (2
  • NCO-reactive compounds with tertiary nitrogen atoms are preferably diamines of the general formula purple or IHb
  • R 2 to R 4 have the meanings given above and R 5 denotes Ci to Cs-alkyl or forms a five- or six-membered ring, in particular a piperazine ring, with R 2 .
  • Particularly suitable diamines are purple, N, N-dimethylethylene diamine, N, N-diethylethylene diamine, N, N-dimethyl-1,3-diamino-2,2-dimethylpropane, N, N-diethyl-1 , 3-propylenediamine, N- (3-aminopropyl) morpholine, N- (2-aminopropyl) morpholine, N- (3-aminopropyl) piperidine, N- (2-aminopropyl) piperidine, 4-amino-1 - (N, N-diethylamino) pentane, 2-amino-1- (N, N-dimethylamino) propane, 2-amino-1- (N, N-diethy
  • Particularly suitable diamines IIIb are N, N, N'-trimethylethylene diamine, N, N, N '-triethylethylene diamine, N-methylpiperazine or N-ethylpiperazine.
  • polyether (poly) ols with built-in tertiary nitrogen atoms which can be prepared by propoxylation and / or ethoxylation of starter molecules containing amine nitrogen, can also be used as NCO-reactive compounds.
  • Such polyether (poly) oles are, for example, the propoxylation and ethoxylation products of ammonia, ethanolamine, diethanolamine, ethylenediamine or N-methylaniline.
  • NCO-reactive compounds which can be used are polyester and polyamide resins having tertiary nitrogen atoms, polyols containing urethane groups and tertiary nitrogen atoms, and polyhydroxy polyacrylates having tertiary nitrogen atoms.
  • the described diisocyanates and / or higher functionalized polyisocyanates can also be reacted with a mixture of nonionically hydrophilically modifying and cationically hydrophilically modifying compounds which are added in succession or simultaneously, for example with a deficit of polyethers I and amino alcohols II or the diamonds purple or Illb. Mixtures of nonionically hydrophilically modifying and anionically hydrophilically modifying compounds are also possible.
  • the content of the hydrophilically modified polyisocyanates to be used in accordance with the invention in hydrophilicizing components which have reacted via their NCO-reactive groups with the described diisocyanates and / or higher-functionalized polyisocyanates to give the present products is generally 0.1 to 40% by weight, preferably 0.5 to 30% by weight, in particular 1.0 to 20% by weight, based on the weight of the product.
  • this content is generally 1 to 40% by weight, preferably 3 to 30% by weight, in particular 5 to 20% by weight
  • this content is generally 0.1 to 10% by weight, preferably 0.5 to 7% by weight, in particular 1.0 to 3% by weight.
  • hydrophilically modified polyisocyanates are used in aqueous media, the polyisocyanates must be sufficiently dispersible.
  • certain reaction products of di- or polyisocyanates and hydroxyl-terminated polyethers (polyether alcohols), such as the compounds I preferably act as emulsifiers for this purpose.
  • hydrophilically modified polyisocyanates are added to the paper stock in amounts of 0.05 to 20, preferably 0.5 to 5% by weight, based on dry fibers, or applied to the surface of the dry paper.
  • polymers containing vinylamine units are used as cationic polymers. Suitable polymers containing vinylamine units are known from the publications cited above, e.g. US-A-4 421 602, US-A-2 721 140, EP-B-0 216 387 and
  • Both hydrolyzed homopolymers of N-vinylformamide and hydrolyzed copolymers of N-vinylformamide with other monoethylenically unsaturated compounds can be used together with the hydrophilically modified polyisocyanates.
  • the vinylamine groups of the polymers can be in the form of salts or as a free base.
  • the hydrolysis or elimination of formyl groups from polymers which contain copolymerized N-vinylamide is preferably achieved by adding acids or bases and heating the reaction mixture to higher temperatures, for example in the temperature range from 20 to 200, preferably 50 to 90 ° C. .
  • Hydrolyzed homopolymers of N-vinylformamide or hydrolyzed copolymers of N-vinylformamide with vinyl acetate, vinyl propionate, C 1 -C 4 -alkyl vinyl ethers, N-vinyl pyrrolidone, acrylamide, methacrylamide, acrylonitrile, methacrylonitrile and esters of acrylic acid and methacrylic acid are preferably used which are derived from alcohols having 1 to 18 carbon atoms and which can be obtained from the polymers by subsequent cleavage of 1 to 99, preferably 5 to 90 mol% of the formyl groups.
  • the copolymers contain, for example, 95 to 10 mol%
  • N-vinylformamide and 5 to 90 mol% of at least one ethylenically unsaturated monomer.
  • the hydrolysis of the copolymers of N-vinylformamide and vinyl formate, vinyl acetate and / or vinyl propionate can be carried out in this way, and the comonomers can also be partially or completely hydrolyzed, for example by hydrolysis of copolymers of N-vinylformamide and vinyl esters of saturated carboxylic acids with 1 to 3 carbon atoms split off 30 to 100 mol% of the formyl groups from the copolymerized N-vinylformamide units and 30 to 100 mol% from the polymerized vinyl ester units to form vinyl alcohol units.
  • the hydrolysis of homopolymers and copolymers of N-vinylformamide is preferably carried out in such a way that 20 to 50 mol% of the formyl groups of N-vinylformamide are hydrolyzed to form vinylamine units.
  • Suitable polymers containing vinylamine units are graft polymers which contain grafted N-vinylformamide and optionally other monoethylenically unsaturated monomers, for example graft polymers of N-vinylformamide onto polyalkylene glycols, for example polyethylene glycol with molar masses of about 400 to 100,000, preferably 1000 to 10000, block copolymers of ethylene oxide and propylene oxide, block copolymers of ethylene oxide and butylene oxide, block copolymers of ethylene oxide, propylene oxide and butylene oxide, it being possible for the block copolymers to contain the alkylene oxide units in any order.
  • addition products of alkylene oxides with alcohols, amines and carboxylic acids are suitable as the graft base. These addition products can optionally be end group-capped, for example etherified with a C 1 -C 22 -alkyl radical or esterified with carboxylic acids.
  • Polyalkylene glycols which are water-soluble and water-dispersible are preferably used.
  • the molar mass of the block copolymers and the addition products of alkylene oxides having 2 to 4 carbon atoms is preferably 200 to 100,000.
  • 0.1 to 20 preferably 1 to 10 parts by weight of N- are used per part by weight of the polyalkylene glycols used as the graft base.
  • Vinylformamide is preferably 1 to 10 parts by weight of N- are used per part by weight of the polyalkylene glycols used as the graft base.
  • the graft polymers are hydrolyzed by adding acids or bases in such a way that vinylamine units are formed from the grafted-on N-vinylformamides with elimination of the formyl group.
  • Polyvinyl esters or copolymers of such esters can also be used as the graft base for N-vinylformamide.
  • Preferred polyesters are, for example, polyvinyl formate and polyvinyl acetate. These copolymers can be used either directly or after hydrolysis, for example hydrolyzing 20 to 100, preferably 60 to 95% of the formate or acetate groups from the monopolymer cured vinyl esters to form vinyl alcohol units.
  • the molar mass of the hydrolyzed polyvinyl esters is, for example, 1000 to 1 million. 1 to 5, preferably 3 to 5 parts by weight of N-vinylformamide, if appropriate in a mixture with other monoethylenically unsaturated monomers, are grafted onto 1 part by weight of the non-hydrolyzed or hydrolyzed polyvinyl esters.
  • the graft polymers are converted into graft polymers containing vinylamine units by hydrolysis with acids or bases by elimination of formyl groups from the polymerized N-vinylformamide.
  • the grafted-on N-vinylformamide can be hydrolyzed to 10 to 100, preferably 20 to 50% by weight to form polymers containing vinylamine units.
  • the polymers containing vinylamine units described above are added to the paper stock in amounts of 0.05 to 20, preferably 0.1 to 5% by weight, based on dry fibers, or applied to the surface of the dry paper.
  • the polymers containing vinylamine units are preferably soluble in water. They have K values according to Fikentscher of 8 to 250, preferably 10 to 150 (measured in 1% by weight aqueous solution at 25 ° C. and pH 7).
  • the joint use of hydrophilically modified polyisocyanates and polymers containing vinyl lamin units in the production of dry-strength and wet-strength finished paper gives one
  • the combinations to be used according to the invention can be added to the paper stock prior to sheet formation, or applied to the surface of a paper sheet that has already been formed.
  • Per part by weight of hydrophilically modified polyisocyanates for example, 0.05 to 20, preferably 0.1 to 5 parts by weight of polymers containing vinylamine units are used, in each case based on the solids content.
  • the combinations to be used according to the invention have the advantage that they are practically not sensitive to impurities, i.e. they can also be used in paper factories with closed water circuits.
  • combinations of hydrophilically modified polyisocyanates and reaction products of polyamidoamines and / or polyamines and epichlorohydrin, for example are highly sensitive to impurities.
  • hydrophilically modified polyisocyanates and polymers containing vinylamine units to be used according to the invention are therefore preferred for the production of hygienic papers which are not exclusively made from fresh cellulose manufactured, but contain recycled fibers, and used in the manufacture of kraft paper.
  • Sulphite pulps which are known as TCF (totally chlorine free) and ECF (elemental chlorine free) qualities, are used for example for the production of hygiene papers.
  • TCF totally chlorine free
  • ECF electrochemical chlorine free
  • sulfate pulps can be used which are not washed as heavily or which are unbleached or half-bleached. Such sulfate pulps occur, for example, in integrated paper mills, in which pulp and paper are produced.
  • combinations to be used according to the invention can optionally be used together with customary auxiliaries, such as alkyldiketenes for sizing paper or with fixing agents.
  • the percentages in the examples mean% by weight, unless stated otherwise.
  • the K value of the polymers was determined according to H. Fikentscher, Zellulose-Chemie, Volume 13, pages 58 to 64 and 71 to 74 (1932), at a temperature of 25 ° C in 5% saline and a polymer concentration of 0.5 % By weight.
  • Homopolymer of N-vinylformamide with a K value of 85 from which 95 mol% of the formyl groups were split off by hydrolysis with hydrochloric acid, in a 12% aqueous solution with a pH value of 5.
  • Aqueous solution of a commercially available neutral wet strength resin based on a reaction product of epichlorohydrin and a polyamidoamine from diethylene triamine and adipic acid is a commercially available neutral wet strength resin based on a reaction product of epichlorohydrin and a polyamidoamine from diethylene triamine and adipic acid.
  • a pulp suspension with a fiber concentration of 0.5% was first prepared by introducing a mixture of 50% spruce sulfite pulp and 50% beech sulfite pulp in water.
  • the pH of the suspension was 7.8, the freeness 29 ° SR (Schopper-Riegler).
  • This pulp suspension was divided into 4 identical parts, which are referred to below as (a) to (d).
  • the additives shown in Table 1 were added to the substance suspensions (b) to (d).
  • leaves with a basis weight of 80 g / m 2 were produced from the material suspensions (a) to (d) on a Rapid-Köthen laboratory sheet former.
  • the wet tear length of the sheets obtained in each case was determined in the unaged condition and after aging for 5 minutes at a temperature of 110 ° C. The results are shown in Table 1.
  • Example 1 Additional wet tear length [m] of the leaves aged without aging
  • a pulp suspension with a concentration of 0.5% was prepared by introducing a fiber mixture of 50% spruce sulfite pulp and 50% beech sulfite pulp and 2% alum in water. The pH of the pulp suspension was 4.5 and the freeness was 29 ° SR. The stock suspension was then divided into 4 identical parts, and the additives shown in Table 2 were added to the stock suspensions (b) to (d). In each case, sheets with a basis weight of 80 g / m 2 were formed from the material suspensions obtained in this way on a Rapid Köthen sheet former. As stated in Example 1, the wet tear length was determined. The results are shown in Table 2.
  • a 0.5% pulp suspension was prepared by adding bleached pine sulphate pulp to water.
  • the pH of the suspension was 7.5, the freeness was 25 ° SR.
  • the pulp suspension was then divided into 8 equal parts, the substances described there being added to the suspensions given in Table 3 under (b) to (h). Thereafter, sheets with a basis weight of 80 g / m 2 were formed from the substance suspensions (a) to (h) in a Rapid Köthen laboratory sheet former.
  • the wet tear lengths of the leaves are given in Table 3.
  • Examples 3 (b) to (h) were repeated with the single exception that 1%, based on dry fiber, of a mixture of lignin sulfonate and humic acid in a weight ratio of 1: 1 was added to the paper stock. The results are shown in Table 4.

Abstract

A process is disclosed for producing paper with a dry-strength and wet-strength finish by adding to the paper pulp combinations of hydrophilically modified polyisocyanates and polymers containing vinyl amine units, then by dewatering the paper pulp to form sheets of paper, or by treating the paper surface with hydrophilically modified polyisocyanates and polymers containing vinyl amine units. Also disclosed is the use of said combinations of polyisocyanates and polymers as dry-strengthening and wet-strengthening agents of hygienic and kraft papers.

Description

Verfahren zur Herstellung von trockenfest und naßfest ausgerüste¬ tem Papier Process for the production of dry-strength and wet-strength finished paper
Beschreibungdescription
Die Erfindung betrifft ein Verfahren zur Herstellung von trocken- fest und naßfest ausgerüstetem Papier durch Zugabe von hydrophil modifizierten Polyisocyanaten und kationischen Polymeren zum Papierstoff und Entwässern des Papierstoffs unter Blattbildung oder durch Behandeln der Oberfläche von Papier mit hydrophil modifizierten Polyisocyanaten und kationischen Polymeren.The invention relates to a process for producing dry-strength and wet-strength paper by adding hydrophilically modified polyisocyanates and cationic polymers to the pulp and dewatering the pulp with sheet formation or by treating the surface of paper with hydrophilically modified polyisocyanates and cationic polymers.
Aus der US-A-4 421 602 sind partiell hydrolysierte, wasserlös- liehe Polymerisate des N-Vinylformamids bekannt, die N-Vinylform- amid-Einheiten und Vinylamin-Einheiten enthalten. Die Poly¬ merisate werden als Mittel zur Erhöhung der Flockung, Retention und Entwässerungsgeschwindigkeit bei der Herstellung von Papier verwendet.US Pat. No. 4,421,602 discloses partially hydrolyzed, water-soluble polymers of N-vinylformamide which contain N-vinylformamide units and vinylamine units. The polymers are used as agents for increasing flocculation, retention and dewatering speed in the manufacture of paper.
Aus der EP-B-0 216 387 sind Trocken- und Naßverfestiger für Papier bekannt, die durch Copolymerisieren von N-Vinylformamid und monoethylenisch ungesättigten Monomeren wie Vinylacetat, N-Vinylpyrrolidon, Acrylnitril oder Acrylester und anschließende Abspaltung von 30 bis 100 Mol-% der Formylgruppen aus den Copoly¬ merisaten erhältlich sind.From EP-B-0 216 387 dry and wet strengthening agents for paper are known which are obtained by copolymerizing N-vinylformamide and monoethylenically unsaturated monomers such as vinyl acetate, N-vinylpyrrolidone, acrylonitrile or acrylic ester and then splitting off from 30 to 100 mol% of the Formyl groups are available from the copolymers.
Andere Vinylamin-Einheiten enthaltende Copolymerisate, die als Trocken- und Naßverfestiger bei der Herstellung von Papier verwendet werden können, sind beispielsweise aus der EP-B-0 251 182 bekannt.Other copolymers containing vinylamine units which can be used as dry and wet strength agents in the production of paper are known, for example, from EP-B-0 251 182.
Aus der EP-A-0 564 912 ist die Verwendung von wasserdispergier¬ baren Polyisocyanaten zur Naßfestausrüstung von Papier bekannt. Der Vorteil dieser Naßverfestiger besteht darin, daß sie kein organisch gebundenes Chlor aufweisen. Die wasserdispergierbaren Polyisocyanate können gemäß der Lehre dieser Veröffentlichung auch im Gemisch von konventionellen Retentions- oder Naßfest- mittein eingesetzt werden. Beispielhaft genannt werden Polyamido- amin-Epichlorhydrin-Harze. Solche Harze enthalten jedoch orga¬ nisch gebundenes Chlor.EP-A-0 564 912 discloses the use of water-dispersible polyisocyanates for the wet-strength finishing of paper. The advantage of these wet strength agents is that they have no organically bound chlorine. According to the teaching of this publication, the water-dispersible polyisocyanates can also be used in a mixture of conventional retention or wet strength agents. Polyamidoamine-epichlorohydrin resins are mentioned by way of example. However, such resins contain organically bound chlorine.
Aus der EP-A-0 582 166 ist ein Verfahren zur Herstellung von trockenfest und naßfest ausgerüstetem und/oder geleimtem cellulosehaltigem Material bekannt, wobei das cellulosehaltige Material mit einem wasserdispergierbaren Polyisocyanatgemisch, das tertiäre Amino- und/oder Ammoniumgruppen enthält, behandelt wird. Die wasserdispergierbaren Polyisocyanat-Gemische können auch in Kombination von Reaktivleimungsmitteln wie Alkyldiketenen oder Alkenylbemsteinsäureanhydriden eingesetzt werden. Die Poly¬ isocyanat-Gemisehe können gegebenenfalls mit kationischen Hilfs- mittein wie Retentionsmitteln, Fixiermitteln, Trockenfestmitteln und Naßfestmitteln verwendet werden, z.B. Polyamine, Polyethylen¬ imine, Polyamidoamine und Polyacrylamide. Bevorzugt sind auch hier wiederum kationische Polykondensate aus Polyaminen und Alky- lendihalogeniden, vorzugsweise Dichlorethan. Dadurch kommt man jedoch wieder zu Systemen, die organisch gebundenes Halogen ent¬ halten.EP-A-0 582 166 discloses a process for the production of dry-strength and wet-strength finished and / or sized cellulose-containing material, the cellulose-containing material being treated with a water-dispersible polyisocyanate mixture which contains tertiary amino and / or ammonium groups becomes. The water-dispersible polyisocyanate mixtures can also be used in combination with reactive sizing agents such as alkyldiketenes or alkenyl succinic anhydrides. The polyisocyanate mixtures can optionally be used with cationic auxiliaries such as retention agents, fixing agents, dry strength agents and wet strength agents, for example polyamines, polyethyleneimines, polyamidoamines and polyacrylamides. Again, preference is given here to cationic polycondensates composed of polyamines and alkylene dihalides, preferably dichloroethane. As a result, however, systems are obtained which contain organically bound halogen.
Der Erfindung liegt die Aufgabe zugrunde, die Wirksamkeit von Trocken- und Naßverfestigern, die kein organisch gebundenes Chlor enthalten, zu erhöhen.The invention has for its object to increase the effectiveness of dry and wet strength agents that do not contain organically bound chlorine.
Die Aufgabe wird erfindungsgemäß gelöst mit einem Verfahren zur Herstellung von trockenfest und naßfest ausgerüstetem Papier durch Zugabe von hydrophil modifizierten Polyisocyanaten und kat- ionischen Polymeren zum Papierstoff und Entwässern des Papier¬ stoffs unter Blattbildung oder durch Behandeln der Oberfläche von Papier mit hydrophil modifizierten Polyisocyanaten und kat- ionischen Polymeren, wenn man als kationische Polymere Vinylamin- Einheiten enthaltende Polymerisate einsetzt.The object is achieved according to the invention with a process for the production of dry-strength and wet-strength finished paper by adding hydrophilically modified polyisocyanates and cationic polymers to the paper stock and dewatering the paper stock with sheet formation or by treating the surface of paper with hydrophilically modified polyisocyanates and cat - Ionic polymers, if one uses polymers containing vinylamine units as cationic polymers.
Die hydrophil modifizierten Polyisocyanate, die auch als wasser- dispergierbare Polyisocyanate bezeichnet werden, liegen in Form von wäßrigen Dispersionen vor, die im wesentlichen frei von orga¬ nischen Lösemitteln und weiteren Emulgatoren sind.The hydrophilically modified polyisocyanates, which are also referred to as water-dispersible polyisocyanates, are in the form of aqueous dispersions which are essentially free of organic solvents and other emulsifiers.
Als Basis für die erfindungsgemäß verwendeten hydrophil modifi¬ zierten Polyisocyanate dienen übliche Diisocyanate und/oder übli¬ che höher funktionelle Polyisocyanate mit einer mittleren NCO- Funktionalität von 2,0 bis 4,5. Diese Komponenten können alleine oder im Gemisch vorliegen.The basis for the hydrophilically modified polyisocyanates used according to the invention are customary diisocyanates and / or usual higher-functional polyisocyanates with an average NCO functionality of 2.0 to 4.5. These components can be present alone or in a mixture.
Beispiele für übliche Diisocyanate sind aliphatische Diisocyanate wie Tetramethylendiisocyanat, Hexamethylendiisocyanat (1,6-Diiso- cyanatohexan) , Octamethylendiisocyanat, Decamethylendiisocyanat, Dodecamethylendiisocyanat, Tetradecamethylendiisocyanat, Trime- thylhexandiisoeyanat oder Tetramethylhexandiisocyanat, eycloali¬ phatische Diisocyanate wie 1,4-, 1,3- oder 1,2-Diisocyanatocyclo- hexan, 4,4' -Di (isocyanatocyclohexyl)methan, 1-lsocyanato- 3,3, 5-trimethyl-5- (isoeyanatomethyl)cyclohexan (Isophorondiiso- cyanat) oder 2,4- oder 2,6-Diisocyanato-l-methylcyclohexan sowie aromatische Diisocyanate wie 2,4- oder 2,6-Toluylendiisocyanat, Tetramethylxylylendiisocyanat, p-Xylylendiisocyanat, 2,4'- oder 4, 4' -Diisocyanatodiphenylmethan, 1,3- oder 1,4 -Phenylendiiso- cyanat, l-Chlor-2, 4-phenylendiisocyanat, 1, 5-Naphthylendiiso- cyanat, Diphenylen-4,4' -diisocyanat, 4,4' -Diisocyanato-3, 3' -dime- thyldiphenyl, 3-Methyldiphenylmethan-4,4' -diisocyanat oder Diphenylether-4, 4' -diisocyanat. Es können auch Gemische der ge¬ nannten Diisocyanate vorliegen.Examples of customary diisocyanates are aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate (1,6-diisocyanate hexane), octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, trimethylhexane diisocyanate, 1,4-diisocyanate, or tetramate diisocyanate, or tetramate diisocyanate, or tetramate diisocyanate such as 1,3-diisocyanate 1,2-diisocyanatocyclohexane, 4,4'-di (isocyanatocyclohexyl) methane, 1-isocyanato-3,3, 5-trimethyl-5- (isoeyanatomethyl) cyclohexane (isophorone diisocyanate) or 2,4- or 2, 6-diisocyanato-l-methylcyclohexane and aromatic diisocyanates such as 2,4- or 2,6-tolylene diisocyanate, tetramethylxylylene diisocyanate, p-xylylene diisocyanate, 2,4'- or 4,4'-diisocyanatodiphenylmethane, 1,3- or 1,4-phenylene diisocyanate, l-chloro-2,4,4-phenylene diisocyanate, 1,5-naphthylene diisocyanate, diphenylene 4,4'-diisocyanate, 4,4 '-Diisocyanato-3, 3' -dimethyldiphenyl, 3-methyldiphenylmethane-4,4'-diisocyanate or diphenylether-4,4'-diisocyanate. Mixtures of the diisocyanates mentioned can also be present.
Bevorzugt werden hiervon aliphatische Diisocyanate, insbesondere Hexamethylendiisocyanat und Isophorondiisocyanat.Of these, aliphatic diisocyanates, in particular hexamethylene diisocyanate and isophorone diisocyanate, are preferred.
Als übliche höher funktionelle Polyisocyanate eignen sich bei¬ spielsweise Triisocyanate wie 2,4,6-Triisocyanatotoluol oder 2, 4, 4' -Triisocyanatodiphenylether oder die Gemische aus Di-, Tri- und höheren Polyisocyanaten, die durch Phosgenierung von entsprechenden Anilin/Formaldehyd-Kondensaten erhalten werden und Methylenbrücken aufweisende Polyphenylpolyisocyanate darstellen.Examples of suitable higher-functional polyisocyanates are triisocyanates such as 2,4,6-triisocyanatotoluene or 2,4,4'-triisocyanatodiphenyl ether or the mixtures of di-, tri- and higher polyisocyanates obtained by phosgenation of the corresponding aniline / formaldehyde Condensates are obtained and represent polyphenyl polyisocyanates having methylene bridges.
Von besonderem Interesse sind übliche aliphatische höher funk¬ tionelle Polyisocyanate der folgenden Gruppen:Common aliphatic, higher functional polyisocyanates of the following groups are of particular interest:
(a) Isocyanuratgruppen aufweisende Polyisocyanate von aliphati¬ schen und/oder cycloaliphatischen Diisocyanaten. Besonders bevorzugt sind hierbei die entsprechenden Isocyanato-Isocya- nurate auf Basis von Hexamethylendiisocyanat und Isophorondi¬ isocyanat. Bei den vorliegenden Isocyanuraten handelt es sich insbesondere um einfache Tris-isocyanatoalkyl- bzw. Triiso- cyanatocycloalkyl-Isocyanurate, welche cyclische Trimere der Diisocyanate darstellen, oder um Gemische mit ihren höheren, mehr als einen Isocyanuratring aufweisenden Homologen. Die Isocyanato-Isocyanurate haben im allgemeinen einen NCO-Gehalt von 10 bis 30 Gew. -%, insbesondere 15 bis 25 Gew. -%, und eine mittlere NCO-Funktionalität von 2,6 bis 4,5.(a) Polyisocyanates of aliphatic and / or cycloaliphatic diisocyanates containing isocyanurate groups. The corresponding isocyanato-isocyanates based on hexamethylene diisocyanate and isophorone diisocyanate are particularly preferred. The present isocyanurates are, in particular, simple tris-isocyanatoalkyl or triisocyanatocycloalkyl isocyanurates, which are cyclic trimers of the diisocyanates, or mixtures with their higher homologues having more than one isocyanurate ring. The isocyanato-isocyanurates generally have an NCO content of 10 to 30% by weight, in particular 15 to 25% by weight, and an average NCO functionality of 2.6 to 4.5.
(b) Uretdiondiisocyanate mit aliphatisch und/oder cycloali- phatisch gebundenen Isocyanatgruppen, vorzugsweise von Hexa- methylendiisocyanat oder Isophorondiisocyanat abgeleitet. Bei Uretdiondiisocyanaten handelt es sich um cyclische Dimer- sierungsprodukte von Diisocyanaten.(b) uretdione diisocyanates with aliphatic and / or cycloaliphatic bound isocyanate groups, preferably derived from hexamethylene diisocyanate or isophorone diisocyanate. Uretdione diisocyanates are cyclic dimerization products of diisocyanates.
(c) Biuretgruppen aufweisende Polyisocyanate mit aliphatisch gebundenen Isocyanatgruppen, insbesondere Tris (6-isocyanato- hexyDbiuret oder dessen Gemische mit seinen höheren Homo¬ logen. Diese Biuretgruppen aufweisenden Polyisocyanate haben im allgemeinen einen NCO-Gehalt von 18 bis 25 Gew. -% und eine mittlere NCO-Funktionalität von 3 bis 4,5. (d) Urethan- und/oder Allophanatgruppen aufweisende Polyiso¬ cyanate mit aliphatisch oder cycloaliphatisch gebundenen Isocyanatgruppen, wie sie beispielsweise durch Umsetzung von überschüssigen Mengen an Hexamethylendiisocyanat oder an Isophorondiisocyanat mit einfachen mehrwertigen Alkoholen wie Trimethylolpropan, Glycerin, 1, 2-Dihydroxypropan oder deren Gemischen erhalten werden können. Diese Urethan- und/oder Allophanatgruppen aufweisenden Polyisocyanate haben im all¬ gemeinen einen NCO-Gehalt von 12 bis 20 Gew. -% und eine mittlere NCO-Funktionalität von 2,5 bis 3.(c) Polyisocyanates containing biuret groups with aliphatically bound isocyanate groups, in particular tris (6-isocyanato-hexyDbiuret or its mixtures with its higher homologues. These polyisocyanates containing biuret groups generally have an NCO content of 18 to 25% by weight and a average NCO functionality from 3 to 4.5. (d) Polyisocyanates containing urethane and / or allophanate groups with aliphatically or cycloaliphatically bound isocyanate groups, such as, for example, by reacting excess amounts of hexamethylene diisocyanate or isophorone diisocyanate with simple polyhydric alcohols such as trimethylolpropane, glycerol, 1, 2-dihydroxypropane or their mixture can be obtained. These polyisocyanates containing urethane and / or allophanate groups generally have an NCO content of 12 to 20% by weight and an average NCO functionality of 2.5 to 3.
(e) Oxadiazintriongruppen enthaltende Polyisocyanate, vorzugs¬ weise von Hexamethylendiisocyanat oder Isophorondiisocyanat abgeleitet. Solche Oxadiazintriongruppen enthaltenden Poly- isocyanate sind aus Diisocyanat und Kohlendioxid herstellbar.(e) Polyisocyanates containing oxadiazinetrione groups, preferably derived from hexamethylene diisocyanate or isophorone diisocyanate. Such polyisocyanates containing oxadiazinetrione groups can be prepared from diisocyanate and carbon dioxide.
(f) Uretonimin-modifizierte Polyisocyanate.(f) Uretonimine-modified polyisocyanates.
Für die erfindungsgemäße Verwendung werden aliphatische Diiso- cyanate und aliphatische höher funktionelle Polyisocyanate beson¬ ders bevorzugt.Aliphatic diisocyanates and aliphatic higher-functional polyisocyanates are particularly preferred for the use according to the invention.
Die beschriebenen Diisocyanate und/oder höher funktionalisierten Polyisocyanate werden zur Überführung in nicht-ionisch hydrophil modifizierte Polyisocyanate, die für die erfindungsgemäße Verwen¬ dung besonders bevorzugt werden, mit NCO-reaktiven Verbindungen umgesetzt, die hydrophil machende Strukturelemente mit nicht- ionischen Gruppen oder mit polaren Gruppen, die nicht in Ionen¬ gruppen übergeführt werden können, enthalten. Dabei liegt das Diisocyanat bzw. Polyisocyanat im stöchiometrischen Überschuß vor, damit das resultierende hydrophil modifizierte Polyisocyanat noch freie NCO-Gruppen aufweist.The described diisocyanates and / or higher functionalized polyisocyanates are converted to NCO-reactive compounds for conversion into non-ionically hydrophilically modified polyisocyanates, which are particularly preferred for the use according to the invention, and the hydrophilic structural elements with non-ionic groups or with polar Contain groups that cannot be converted into ion groups. The diisocyanate or polyisocyanate is present in a stoichiometric excess so that the resulting hydrophilically modified polyisocyanate still has free NCO groups.
Als solche NCO-reaktive Verbindungen mit hydrophil machenden Strukturelementen kommen vor allem hydroxylgruppenterminierte Polyether der allgemeinen Formel IHydroxyl group-terminated polyethers of the general formula I in particular come as such NCO-reactive compounds with hydrophilicizing structural elements
Ri_χ_(AO)n-H (I)R i _χ_ (AO) n -H (I)
in derin the
R1 für Cx- bis C20-Alkyl, insbesondere Ci- bis C4-Alkyl, oder C2- bis C20-Alkenyl, Cyclopentyl, Cyclohexyl, Glycidyl, Oxethyl, Phenyl, Tolyl, Benzyl, Furfuryl oder Tetrahydrofurfuryl steht, X Schwefel oder insbesondere Sauerstoff bezeichnet,R 1 represents Cx to C 20 alkyl, in particular C 1 to C 4 alkyl, or C 2 to C 20 alkenyl, cyclopentyl, cyclohexyl, glycidyl, oxethyl, phenyl, tolyl, benzyl, furfuryl or tetrahydrofurfuryl, X denotes sulfur or in particular oxygen,
A Propylen oder vor allem Ethylen bedeutet, wobei auch ins¬ besondere blockweise gemischt ethoxylierte und propoxylierte Verbindungen auftreten können, undA means propylene or, above all, ethylene, and in particular mixed ethoxylated and propoxylated compounds can also occur in blocks, and
n für eine Zahl von 5 bis 120, insbesondere 10 bis 25 steht,n stands for a number from 5 to 120, in particular 10 to 25,
in Betracht.into consideration.
Hierbei handelt es sich besonders bevorzugt um auf Ci- bis C4-Alkanol gestartete Ethylenoxid- oder Propylenoxid-Polyether mit mittleren Molekulargewichten von 250 bis 7000, insbesondere 450 bis 1500.This is particularly preferred in order to Ci- to C 4 alkanol started ethylene oxide or propylene oxide polyethers having average molecular weights of from 250 to 7000, in particular from 450 to 1,500.
Man kann aus den beschriebenen Diisocyanaten und/oder höher funk- tionalisierte Polyisocyanaten auch zuerst durch Umsetzung mit einem Unterschuß an hydroxylgruppenterminierten Polyestern, an anderen hydroxylgruppenterminierten Polyethern oder an Polyolen, z.B. Ethylenglykol, Trimethylolpropan oder Butandiol, Präpolymere erzeugen und diese Präpolymere dann anschließend oder auch gleichzeitig mit den Polyethern I im Unterschuß zu den hydrophil modifizierten Polyisocyanaten mit freien NCO-Gruppen umsetzen.From the described diisocyanates and / or more functionalized polyisocyanates, it is also possible first of all by reaction with a deficit of hydroxyl-terminated polyesters, on other hydroxyl-terminated polyethers or on polyols, e.g. Generate ethylene glycol, trimethylolpropane or butanediol, prepolymers and then implement these prepolymers either subsequently or simultaneously with the polyethers I in deficit to the hydrophilically modified polyisocyanates with free NCO groups.
Es ist auch möglich, nicht-ionisch hydrophil modifizierte Poly¬ isocyanate aus Diisocyanat bzw. Polyisocyanat und Polyalkylen- glykolen der Formel HO—(AO)n—H, in der A und n die oben genannten Bedeutungen haben, herzustellen. Dabei reagieren beide endständi¬ gen OH-Gruppen des Polyalkylenglykols mit Isocyanat ab.It is also possible to prepare nonionically hydrophilically modified polyisocyanates from diisocyanate or polyisocyanate and polyalkylene glycols of the formula HO— (AO) n —H, in which A and n have the meanings given above. Both terminal OH groups of the polyalkylene glycol react with isocyanate.
Die aufgezählten Arten nicht-ionisch hydrophil modifizierter Polyisocyanate sind in den Schriften DE-A 24 47 135, DE-A 26 10 552, DE-A 29 08 844, EP-A 0 13 112, EP-A 019 844, DE-A 40 36 927, DE-A 41 36 618, EP-B 206 059, EP-A 464 781 und EP-A 516 361 näher beschrieben.The enumerated types of non-ionically hydrophilically modified polyisocyanates are in the documents DE-A 24 47 135, DE-A 26 10 552, DE-A 29 08 844, EP-A 0 13 112, EP-A 019 844, DE-A 40 36 927, DE-A 41 36 618, EP-B 206 059, EP-A 464 781 and EP-A 516 361.
Die beschriebenen Diisocyanate und/oder höher funktionalisierten Polyisocyanate werden zur Überführung in anionisch hydrophil modifizierte Polyisocyanate mit NCO-reaktiven Verbindungen umge- setzt, die hydrophil machende anionische Gruppen, insbesondere Säuregruppen wie Carboxylgruppen, Sulfonsäuregruppen oder Phosphonsäuregruppen, enthalten. Dabei liegt das Diisocyanat bzw. Polyisocyanat im stöchiometrischen Überschuß vor, damit das resultierende hydrophil modifizierte Polyisocyanat noch freie NCO-Gruppen aufweist. Als solche NCO-reaktiven Verbindungen mit anionischen Gruppen kommen vor allem Hydroxyearbonsauren wie 2-Hydroxyessigsäure, 3-Hydroxypropionsäure, 4-Hydroxybuttersäure oder Hydroxypivalin¬ säure sowie 2,2-Bis- und 2,2,2-Tris(hydroxymethyl)alkansäuren, z.B. 2,2-Bis (hydroxymethyl)essigsaure, 2, 2-Bis(hydroxy¬ methyl)propionsäure, 2,2-Bis (hydroxymethyl)buttersäure oder 2, 2, 2-Tris(hydroxymethyl)essigsaure, in Betracht. Die Carboxyl¬ gruppen können teilweise oder vollständig durch eine Base neutralisiert sein, um in einer wasserlöslichen oder wasser- dispergierbaren Form vorzuliegen. Als Base tritt hierbei vorzugs¬ weise ein tertiäres Amin auf, welches bekanntermaßen gegenüber Isocyanat inert ist.The described diisocyanates and / or higher functionalized polyisocyanates are converted into anionically hydrophilically modified polyisocyanates with NCO-reactive compounds which contain hydrophilic anionic groups, in particular acid groups such as carboxyl groups, sulfonic acid groups or phosphonic acid groups. The diisocyanate or polyisocyanate is present in a stoichiometric excess so that the resulting hydrophilically modified polyisocyanate still has free NCO groups. Such NCO-reactive compounds with anionic groups are, above all, hydroxyearonic acids such as 2-hydroxyacetic acid, 3-hydroxypropionic acid, 4-hydroxybutyric acid or hydroxypivalic acid and 2,2-bis- and 2,2,2-tris (hydroxymethyl) alkanoic acids, for example 2,2-bis (hydroxymethyl) acetic acid, 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (hydroxymethyl) butyric acid or 2,2,2-tris (hydroxymethyl) acetic acid. The carboxyl groups can be partially or completely neutralized by a base in order to be present in a water-soluble or water-dispersible form. The base used here is preferably a tertiary amine, which is known to be inert to isocyanate.
Die beschriebenen Diisocyanate und/oder höher funktionalisierten Polyisocyanate können auch mit einer Mischung aus nicht-ionisch hydrophil modifizierenden und anionisch hydrophobil modifizieren¬ den Verbindungen, welche nacheinander oder gleichzeitig zugegeben werden, umgesetzt werden, beispielsweise mit einem Unterschuß aus den Polyethern I und den beschriebenen Hydroxyearbonsauren.The described diisocyanates and / or more highly functionalized polyisocyanates can also be reacted with a mixture of nonionically hydrophilically modifying and anionically hydrophobically modifying compounds which are added in succession or simultaneously, for example with a deficiency of the polyethers I and the described hydroxyearonic acids .
Die aufgezählten Arten anionisch hydrophil modifizierter Polyiso¬ cyanate sind in den Schriften DE-A-40 01 783, DE-A-41 13 160 und DE-A-41 42 275 näher beschrieben.The enumerated types of anionically hydrophilically modified polyisocyanates are described in more detail in documents DE-A-40 01 783, DE-A-41 13 160 and DE-A-41 42 275.
Die beschriebenen Diisocyanate und/oder höher funktionalisierten Polyisocyanate werden zur Überführung in kationisch hydrophil modifizierte Polyisocyanate mit NCO-reaktiven Verbindungen umge¬ setzt, die chemisch eingebaute alkylierbare oder protonierbare Funktionen unter Ausbildung eines kationischen Zentrums ent- halten. Insbesondere sind solche Funktionen tertiäre Stickstoff- atome, welche bekanntermaßen gegenüber Isocyanat inert sind und sich leicht quaternieren oder protonieren lassen. Bei der Um¬ setzung von Diisocyanat bzw. Polyisocyanat mit diesen NCO-reak¬ tiven Verbindungen liegen erstere im Überschuß vor, damit das resultierende hydrophil modifizierte Polyisocyanat noch freie NCO-Gruppen aufweist.The described diisocyanates and / or more highly functionalized polyisocyanates are converted into cationically hydrophilically modified polyisocyanates with NCO-reactive compounds which contain chemically incorporated alkylatable or protonatable functions with the formation of a cationic center. In particular, such functions are tertiary nitrogen atoms, which are known to be inert to isocyanate and can be easily quaternized or protonated. When diisocyanate or polyisocyanate is reacted with these NCO-reactive compounds, the former are in excess so that the resulting hydrophilically modified polyisocyanate still has free NCO groups.
Als derartige NCO-reaktive Verbindungen mit tertiären Stickstoff- atomen kommen vorzugsweise Aminoalkohole der allgemeinen Formel IISuch NCO-reactive compounds with tertiary nitrogen atoms are preferably amino alcohols of the general formula II
R2R2
N-R4-OH (II) NR 4 -OH (II)
R3 ^ in derR 3 ^ in the
R2 und R3 lineares oder verzweigtes Ci- bis C20-Alkyl, insbesondere Ci- bis C5-Alkyl, bedeuten oder zusammen mit dem N-Atom einen fünf- oder sechsgliedrigen Ring bilden, der noch ein O-Atom oder ein tertiäres N-Atom enthalten kann, insbesondere einen Piperidin-, Morpholin-, Piperazin-, Pyrrolidin-, Oxazolin- oder Dihydrooxazin-Ring, wobei die Reste R2 und R3 noch zusätzlich Hydroxylgruppen, insbesondere jeweils eine Hydroxylgruppe, tragen können, undR 2 and R 3 are linear or branched C 1 to C 20 alkyl, in particular C 1 to C 5 alkyl, or together with the N atom form a five- or six-membered ring which is also an O atom or a tertiary one N atom can contain, in particular a piperidine, morpholine, piperazine, pyrrolidine, oxazoline or dihydrooxazine ring, where the radicals R 2 and R 3 can additionally carry hydroxyl groups, in particular in each case one hydroxyl group, and
R4 eine C2- bis Cio-Alkylengruppe, insbesondere eine C2- bis Cβ-Alkylengruppe, die linear oder verzweigt sein kann, bezeichnet,R 4 denotes a C 2 - to Cio-alkylene group, in particular a C 2 - to Cβ-alkylene group, which can be linear or branched,
in Betracht.into consideration.
Als Aminoalkohole II eignen sich vor allem N-Methyldiethanolamin, N-Methyldi (iso)propanolamin, N-Butyldiethanolamin, N-Bu- tyldi(iso)propanolamin, N-Stearyldiethanolamin, N-Stea- ryldi (iso)propanolamin, N,N-Dimethylethanolamin, N,N-Dime- thyl (iso)propanolamin, N,N-Diethylethanolamin, N,N-Di- ethyl (iso)propanolamin, N,N-Dibutylethanolamin, N,N-Dibu- tyl(iso)propanolamin, Triethanolamin, Tri (iso)propanolamin, N- (2-Hydroxyethyl)morpholin, N- (2-Hydroxypropyl)morpholin, N- (2-Hydroxyethyl)piperidin, N- (2-Hydroxypropyl)piperidin, N-Methyl-N' - (2-hydroxyethyl)piperazin, N-Methyl-N' - (2-hydroxy- propyl)piperazin, N-Methyl-N' - (4-hydroxybutyl)piperazin, 2-Hydroxyethyl-oxazolin, 2-Hydroxypropyl-oxazolin, 3-Hydroxy¬ propyl-oxazolin, 2-Hydroxyethyl-dihydrooxazin, 2-Hydroxypropyl- dihydrooxazin oder 3-Hydroxypropyl-dihydrooxazin.Particularly suitable amino alcohols II are N-methyldiethanolamine, N-methyldi (iso) propanolamine, N-butyldiethanolamine, N-butyldi (iso) propanolamine, N-stearyldiethanolamine, N-stearyldi (iso) propanolamine, N, N -Dimethylethanolamine, N, N-dimethyl (iso) propanolamine, N, N-diethylethanolamine, N, N-diethyl (iso) propanolamine, N, N-dibutylethanolamine, N, N-dibutyl (iso) propanolamine , Triethanolamine, tri (iso) propanolamine, N- (2-hydroxyethyl) morpholine, N- (2-hydroxypropyl) morpholine, N- (2-hydroxyethyl) piperidine, N- (2-hydroxypropyl) piperidine, N-methyl-N '- (2-Hydroxyethyl) piperazine, N-methyl-N' - (2-hydroxypropyl) piperazine, N-methyl-N '- (4-hydroxybutyl) piperazine, 2-hydroxyethyl oxazoline, 2-hydroxypropyl oxazoline , 3-Hydroxy¬ propyl-oxazoline, 2-hydroxyethyl-dihydrooxazine, 2-hydroxypropyl-dihydrooxazine or 3-hydroxypropyl-dihydrooxazine.
Weiterhin kommen als derartige NCO-reaktive Verbindungen mit ter- tiären Stickstoffatomen vorzugsweise Diamine der allgemeinen For¬ mel lila oder IHbFurthermore, such NCO-reactive compounds with tertiary nitrogen atoms are preferably diamines of the general formula purple or IHb
R2 R2 R 2 R 2
N-R4-NH2 (ma) N-R4-NH-R5 (IHb) R3 R3 NR 4 -NH 2 (ma) N-R4-NH-R 5 (IHb) R3 R 3
in der R2 bis R4 die oben genannten Bedeutungen haben und R5 Ci bis Cs-Alkyl bezeichnet oder mit R2 einen fünf- oder sechs- gliedrigen Ring, insbesondere einen Piperazin-Ring, bildet, in Betracht. Als Diamine lila eigenen sich vor allem N,N-Dimethyl-ethylen- diamin, N,N-Diethyl-ethylendiamin, N,N-Dimethyl-1, 3-diamino- 2, 2-dimethylpropan, N,N-Diethyl-1, 3-propylendiamin, N-(3-Amino- propyl)morpholin, N- (2-Aminopropyl)morpholin, N-(3-Amino- propyl)piperidin, N- (2-Aminopropyl)piperidin, 4-Amino-1- (N,N-di- ethylamino)pentan, 2-Amino-1- (N,N-dimethylamino)propan, 2-Amino-l- (N,N-diethylamino)propan oder 2-Amino-1- (N,N-diethyl- amino) -2-methylpropan.in which R 2 to R 4 have the meanings given above and R 5 denotes Ci to Cs-alkyl or forms a five- or six-membered ring, in particular a piperazine ring, with R 2 . Particularly suitable diamines are purple, N, N-dimethylethylene diamine, N, N-diethylethylene diamine, N, N-dimethyl-1,3-diamino-2,2-dimethylpropane, N, N-diethyl-1 , 3-propylenediamine, N- (3-aminopropyl) morpholine, N- (2-aminopropyl) morpholine, N- (3-aminopropyl) piperidine, N- (2-aminopropyl) piperidine, 4-amino-1 - (N, N-diethylamino) pentane, 2-amino-1- (N, N-dimethylamino) propane, 2-amino-1- (N, N-diethylamino) propane or 2-amino-1- (N , N-diethylamino) -2-methylpropane.
Als Diamine Illb eignen sich vor allem N,N,N' -Trimethyl-ethylen- diamin, N,N,N' -Triethyl-ethylendiamin, N-Methylpiperazin oder N- Ethylpiperazin.Particularly suitable diamines IIIb are N, N, N'-trimethylethylene diamine, N, N, N '-triethylethylene diamine, N-methylpiperazine or N-ethylpiperazine.
Weiterhin können als NCO-reaktive Verbindungen auch Poly- ether(poly)ole mit eingebauten tertiären Stickstoffatomen, die durch Propoxylierung und/oder Ethoxylierung von Aminstickstoff aufweisenden Startermolekülen herstellbar sind, eingesetzt werden. Derartige Polyether (poly)ole sind beispielsweise die Propoxylierungs- und Ethoxylierungsprodukte von Ammoniak, Ethanolamin, Diethanolamin, Ethylendiamin oder N-Methylanilin.Furthermore, polyether (poly) ols with built-in tertiary nitrogen atoms, which can be prepared by propoxylation and / or ethoxylation of starter molecules containing amine nitrogen, can also be used as NCO-reactive compounds. Such polyether (poly) oles are, for example, the propoxylation and ethoxylation products of ammonia, ethanolamine, diethanolamine, ethylenediamine or N-methylaniline.
Andere verwendbare NCO-reaktive Verbindungen sind tertiäre Stick- Stoffatome aufweisende Polyester- und Polyamidharze, tertiäre Stickstoffatome aufweisende urethangruppenhaltige Polyole sowie tertiäre Stickstoffatome aufweisende Polyhydroxypolyacrylate.Other NCO-reactive compounds which can be used are polyester and polyamide resins having tertiary nitrogen atoms, polyols containing urethane groups and tertiary nitrogen atoms, and polyhydroxy polyacrylates having tertiary nitrogen atoms.
Die beschriebenen Diisocyanate und/oder höher funktionalisierten Polyisocyanate können auch mit einer Mischung aus nicht-ionisch hydrophil modifizierenden und kationisch hydrophil modifizieren- den Verbindungen, welche nacheinander oder gleichzeitig zugegeben werden, umgesetzt werden, beispielsweise mit einem Unterschuß aus den Polyethern I und den Aminoalkoholen II oder den Diaminen lila bzw. Illb. Auch Mischungen aus nicht-ionisch hydrophil modifizie¬ renden und anionisch hydrophil modifizierenden Verbindungen sind möglich.The described diisocyanates and / or higher functionalized polyisocyanates can also be reacted with a mixture of nonionically hydrophilically modifying and cationically hydrophilically modifying compounds which are added in succession or simultaneously, for example with a deficit of polyethers I and amino alcohols II or the diamonds purple or Illb. Mixtures of nonionically hydrophilically modifying and anionically hydrophilically modifying compounds are also possible.
Die aufgezählten Arten kationisch hydrophil modifizierter Poly¬ isocyanate sind in den Schriften DE-A-42 03 510 und EP-A-531 820 näher beschrieben.The enumerated types of cationically hydrophilically modified polyisocyanates are described in more detail in documents DE-A-42 03 510 and EP-A-531 820.
Der Gehalt der erfindungsgemäß zu verwendenden hydrophil modifi¬ zierten Polyisocyanate an hydrophil machenden Komponenten, die über ihre NCO-reaktiven Gruppen mit den beschriebenen Diiso¬ cyanaten und/oder höher funktionalisierten Polyisocyanaten zu den vorliegenden Produkten reagiert haben, beträgt in der Regel 0,1 bis 40 Gew. -%, vorzugsweise 0,5 bis 30 Gew. -%, insbesondere 1,0 bis 20 Gew.-%, bezogen auf das Gewicht des Produktes. Wenn es sich um rein nicht-ionisch hydrophil modifizierte Polyisocyanate handelt, beträgt dieser Gehalt in der Regel 1 bis 40 Gew. -%, vor¬ zugsweise 3 bis 30 Gew. -%, insbesondere 5 bis 20 Gew. -%, handelt es sich dagegen um rein anionisch oder kationisch hydrophil modi- fizierte Polyisocyanate, beträgt dieser Gehalt in der Regel 0,1 bis 10 Gew. -%, vorzugsweise 0,5 bis 7 Gew. -%, insbesondere 1,0 bis 3 Gew. -%.The content of the hydrophilically modified polyisocyanates to be used in accordance with the invention in hydrophilicizing components which have reacted via their NCO-reactive groups with the described diisocyanates and / or higher-functionalized polyisocyanates to give the present products is generally 0.1 to 40% by weight, preferably 0.5 to 30% by weight, in particular 1.0 to 20% by weight, based on the weight of the product. If it if it is purely non-ionically hydrophilic modified polyisocyanates, this content is generally 1 to 40% by weight, preferably 3 to 30% by weight, in particular 5 to 20% by weight Purely anionically or cationically hydrophilically modified polyisocyanates, this content is generally 0.1 to 10% by weight, preferably 0.5 to 7% by weight, in particular 1.0 to 3% by weight.
Da die genannten hydrophil modifizierten Polyisocyanate in wäßrigen Medien eingesetzt werden, ist für eine ausreichende Dispergierbarkeit der Polyisocyanate zu sorgen. Vorzugsweise wirken innerhalb der Gruppe der beschriebenen hydrophil modifi¬ zierten Polyisocyanate bestimmte Umsetzungsprodukte aus Di- bzw. Polyisocyanaten und hydroxylgruppenterminierten Polyethern (Poly- etheralkoholen) wie die Verbindungen I als Emulgatoren für diesen Zweck.Since the hydrophilically modified polyisocyanates mentioned are used in aqueous media, the polyisocyanates must be sufficiently dispersible. Within the group of the hydrophilically modified polyisocyanates described, certain reaction products of di- or polyisocyanates and hydroxyl-terminated polyethers (polyether alcohols), such as the compounds I, preferably act as emulsifiers for this purpose.
Die hydrophil modifizierten Polyisocnate werden in Mengen von 0,05 bis 20, vorzugsweise 0,5 bis 5 Gew.-%, bezogen auf trockene Fasern, dem Papierstoff zugesetzt oder auf die Oberfläche des trockenen Papiers aufgetragen. Als kationische Polymere werden erfindungsgemäß Vinylamin-Einheiten enthaltende Polymerisate eingesetzt. Geeignete Vinylamin-Einheiten enthaltende Polymeri¬ sate sind aus den oben angegebenen Veröffentlichungen bekannt, z.B. US-A-4 421 602, US-A-2 721 140, EP-B-0 216 387 undThe hydrophilically modified polyisocyanates are added to the paper stock in amounts of 0.05 to 20, preferably 0.5 to 5% by weight, based on dry fibers, or applied to the surface of the dry paper. According to the invention, polymers containing vinylamine units are used as cationic polymers. Suitable polymers containing vinylamine units are known from the publications cited above, e.g. US-A-4 421 602, US-A-2 721 140, EP-B-0 216 387 and
EP-A-0 251 182. Man kann sowohl hydrolysierte Homopolymerisate des N-Vinylformamids als auch hydrolysierte Copolymerisate des N-Vinylformamids mit anderen monoethylenisch ungesättigten Verbindungen zusammen mit den hydrophil modifizierten Polyiso- cyanaten einsetzen. Die Vinylamin-Gruppen der Polymerisate können in Form von Salzen oder als freie Base vorliegen. Die Hydrolyse bzw. die Abspaltung von Formylgruppen aus Polymerisaten, die N-Vinylamid einpolymerisiert enthalten, wird vorzugsweise durch Zugabe von Säuren oder Basen und Erhitzen der Reaktionsmischung auf höhere Temperaturen, z.B. in dem Temperaturbereich von 20 bis 200, vorzugsweise 50 bis 90°C erreicht. Vorzugsweise verwendet man hydrolysierte Homopolymerisate des N-Vinylformamids oder hydrolysierte Copolymerisate des N-Vinylformamids mit Vinyl¬ acetat, Vinylpropionat, Ci- bis C4-Alkylvinylethern, N-Vinylpyrro- lidon, Acrylamid, Methacrylamid, Acrylnitril, Methacrylnitril und Estern der Acrylsäure und Methacrylsäure, die sich von Alkoholen mit 1 bis 18 Kohlenstoffatomen ableiten und die durch anschließende Abspaltung von 1 bis 99, vorzugsweise 5 bis 90 Mol-% der Formylgruppen aus den Polymerisaten erhältlich sind. Die Copolymerisate enthalten beispielsweise 95 bis 10 Mol-%EP-A-0 251 182. Both hydrolyzed homopolymers of N-vinylformamide and hydrolyzed copolymers of N-vinylformamide with other monoethylenically unsaturated compounds can be used together with the hydrophilically modified polyisocyanates. The vinylamine groups of the polymers can be in the form of salts or as a free base. The hydrolysis or elimination of formyl groups from polymers which contain copolymerized N-vinylamide is preferably achieved by adding acids or bases and heating the reaction mixture to higher temperatures, for example in the temperature range from 20 to 200, preferably 50 to 90 ° C. . Hydrolyzed homopolymers of N-vinylformamide or hydrolyzed copolymers of N-vinylformamide with vinyl acetate, vinyl propionate, C 1 -C 4 -alkyl vinyl ethers, N-vinyl pyrrolidone, acrylamide, methacrylamide, acrylonitrile, methacrylonitrile and esters of acrylic acid and methacrylic acid are preferably used which are derived from alcohols having 1 to 18 carbon atoms and which can be obtained from the polymers by subsequent cleavage of 1 to 99, preferably 5 to 90 mol% of the formyl groups. The copolymers contain, for example, 95 to 10 mol%
N-Vinylformamid und 5 bis 90 Mol-% mindestens eines ethylenisch ungesättigten Monomeren. Besonders bevorzugt werden als Comono- mere Vinylacetat, N-Vinylpyrrolidon, Acrylnitril und Acrylsäure- ester von Alkoholen mit 1 bis 4 Kohlenstoffatomen eingesetzt. Die Hydrolyse der Copolymerisate aus N-Vinylformamid und Vinyl- formiat, Vinylacetat und/oder Vinylpropionat kann so geführt werden, auch auch die Comonomeren teilweise oder vollständig hydrolysieren, z.B. kann man durch Hydrolyse von Copolymerisaten aus N-Vinylformamid und Vinylestern von gesättigten Carbonsäuren mit 1 bis 3 Kohlenstoffatomen 30 bis 100 Mol-% der Formylgruppen aus den einpolymerisierten N-Vinylformamid-Einheiten und 30 bis 100 Mol-% aus den einpolymerisierten Vinylester-Einheiten unter Bildung von Vinylalkohol-Einheiten abspalten. Die Hydrolyse von Homo- und Copolymerisaten des N-Vinylformamids wird vorzugsweise so geführt, daß 20 bis 50 Mol-% der Formylgruppen des N-Vinyl¬ formamids unter Bildung von Vinylamin-Einheiten hydrolysiert sind.N-vinylformamide and 5 to 90 mol% of at least one ethylenically unsaturated monomer. Particularly preferred as comono- mere vinyl acetate, N-vinylpyrrolidone, acrylonitrile and acrylic acid esters of alcohols with 1 to 4 carbon atoms. The hydrolysis of the copolymers of N-vinylformamide and vinyl formate, vinyl acetate and / or vinyl propionate can be carried out in this way, and the comonomers can also be partially or completely hydrolyzed, for example by hydrolysis of copolymers of N-vinylformamide and vinyl esters of saturated carboxylic acids with 1 to 3 carbon atoms split off 30 to 100 mol% of the formyl groups from the copolymerized N-vinylformamide units and 30 to 100 mol% from the polymerized vinyl ester units to form vinyl alcohol units. The hydrolysis of homopolymers and copolymers of N-vinylformamide is preferably carried out in such a way that 20 to 50 mol% of the formyl groups of N-vinylformamide are hydrolyzed to form vinylamine units.
Weitere geeignete Vinylamin-Einheiten enthaltende Polymerisate sind Pfropfpolymerisate, die N-Vinylformamid und gegebenenfalls andere monoethylenisch ungesättigte Monomere aufgepfropft enthal- ten, z.B. Pfropfpolymerisate von N-Vinylformamid auf Polyalkylen- glykole, z.B. Polyethylenglykol mit Mol-Massen von ca. 400 bis 100000, vorzugsweise 1000 bis 10000, Blockcopolymerisate aus Ethylenoxid und Propylenoxid, Blockcopolymerisate aus Ethylenoxid und Butylenoxid, Blockcopolymerisate aus Ethylenoxid, Propylen- oxid und Butylenoxid, wobei die Blockcopolymerisate die Alkyleno- xid-Einheiten in beliebiger Reihenfolge enthalten können. Außer¬ dem eignen sich als Pfropfgrundlage Additionsprodukte von Alkylenoxiden an Alkohole, Amine und Carbonsäuren. Diese Anlage¬ rungsprodukte können gegebenenfalls endgruppenverschlossen sein, z.B. verethert mit einem Ci- bis C22-Alkylrest oder mit Carbon¬ säuren verestert sein. Vorzugsweise verwendet man solche Poly- alkylenglykole, die wasserlöslich und in Wasser dispergierbar sind. Die Molmasse der Blockcopolymerisate und der Additions- produkte von Alkylenoxiden mit 2 bis 4 C-Atomen beträgt Vorzugs- weise 200 bis 100000. Auf 1 Gewichtsteil der als Pfropfgrundlage eingesetzten Polyalkylenglykole verwendet man beispielsweise 0,1 bis 20, vorzugsweise 1 bis 10 Gewichtsteile N-Vinylformamid. Die Pfropfpolymerisate werden im Anschluß an ihre Herstellung durch Zugabe von Säuren oder Basen in der Weise hydrolysiert, daß aus den aufgepfropften N-Vinylformamiden unter Abspaltung der Formyl- gruppe Vinylamin-Einheiten entstehen. Als Pfropfgrundlage für N-Vinylformamid können außerdem Polyvinylester oder Copoly¬ merisate solcher Ester eingesetzt werden. Bevorzugte Polyester sind beispielsweise Polyvinylformiat und Polyvinylacetat. Diese Copolymerisate können entweder direkt oder nach einer Hydrolyse verwendet werden, z.B. hydrolysiert man 20 bis 100, vorzugsweise 60 bis 95 % der Formiat- bzw. Acetat-Gruppen aus den einpolymeri- sierten Vinylestern unter Bildung von Vinylalkohol-Einheiten ab. Die Molmasse der hydrolysierten Polyvinylester beträgt z.B. 1000 bis 1 Million. Auf 1 Gewichtsteil der nicht hydrolysierten bzw. hydrolysierten Polyvinylester pfropft man 1 bis 5, vorzugsweise 3 bis 5 Gewichtsteile N-Vinylformamid, gegebenenfalls in Mischung mit anderen monoethylenisch ungesättigten Monomeren auf. Die Pfropfpolymerisate werden durch Hydrolyse mit Säuren oder Basen durch Abspaltung von Formylgruppen aus dem einpolymerisierten N- Vinylformamid in Vinylamin-Einheiten enthaltende Pfropfpoly- merisate überführt. Das aufgepfropfte N-Vinylformamid kann zu 10 bis 100, vorzugsweise 20 bis 50 Gew.-% unter Bildung von Vinyl¬ amin-Einheiten enthaltenden Polymerisaten hydrolysiert werden.Other suitable polymers containing vinylamine units are graft polymers which contain grafted N-vinylformamide and optionally other monoethylenically unsaturated monomers, for example graft polymers of N-vinylformamide onto polyalkylene glycols, for example polyethylene glycol with molar masses of about 400 to 100,000, preferably 1000 to 10000, block copolymers of ethylene oxide and propylene oxide, block copolymers of ethylene oxide and butylene oxide, block copolymers of ethylene oxide, propylene oxide and butylene oxide, it being possible for the block copolymers to contain the alkylene oxide units in any order. In addition, addition products of alkylene oxides with alcohols, amines and carboxylic acids are suitable as the graft base. These addition products can optionally be end group-capped, for example etherified with a C 1 -C 22 -alkyl radical or esterified with carboxylic acids. Polyalkylene glycols which are water-soluble and water-dispersible are preferably used. The molar mass of the block copolymers and the addition products of alkylene oxides having 2 to 4 carbon atoms is preferably 200 to 100,000. For example, 0.1 to 20, preferably 1 to 10 parts by weight of N- are used per part by weight of the polyalkylene glycols used as the graft base. Vinylformamide. Following their preparation, the graft polymers are hydrolyzed by adding acids or bases in such a way that vinylamine units are formed from the grafted-on N-vinylformamides with elimination of the formyl group. Polyvinyl esters or copolymers of such esters can also be used as the graft base for N-vinylformamide. Preferred polyesters are, for example, polyvinyl formate and polyvinyl acetate. These copolymers can be used either directly or after hydrolysis, for example hydrolyzing 20 to 100, preferably 60 to 95% of the formate or acetate groups from the monopolymer cured vinyl esters to form vinyl alcohol units. The molar mass of the hydrolyzed polyvinyl esters is, for example, 1000 to 1 million. 1 to 5, preferably 3 to 5 parts by weight of N-vinylformamide, if appropriate in a mixture with other monoethylenically unsaturated monomers, are grafted onto 1 part by weight of the non-hydrolyzed or hydrolyzed polyvinyl esters. The graft polymers are converted into graft polymers containing vinylamine units by hydrolysis with acids or bases by elimination of formyl groups from the polymerized N-vinylformamide. The grafted-on N-vinylformamide can be hydrolyzed to 10 to 100, preferably 20 to 50% by weight to form polymers containing vinylamine units.
Die oben beschriebenen Vinylamin-Einheiten enthaltenden Poly- merisate werden in Mengen von 0,05 bis 20, vorzugsweise 0,1 bis 5 Gew.-%, bezogen auf trockene Fasern, dem Papierstoff zugesetzt oder auf die Oberfläche des trockenen Papiers aufgetragen.The polymers containing vinylamine units described above are added to the paper stock in amounts of 0.05 to 20, preferably 0.1 to 5% by weight, based on dry fibers, or applied to the surface of the dry paper.
Die Vinylamin-Einheiten enthaltenden Polymerisate sind Vorzugs- weise in Wasser löslich. Sie haben K-Werte nach Fikentscher von 8 bis 250, vorzugsweise 10 bis 150 (gemessen in 1 gewichtsprozen¬ tiger wäßriger Lösung bei 25°C und pH 7) . Die gemeinsame Verwendung von hydrophil modifizierten Polyisocyanaten und Viny¬ lamin-Einheiten enthaltenden Polymerisaten bei der Herstellung von trockenfest und naßfest ausgerüstetem Papier ergibt einenThe polymers containing vinylamine units are preferably soluble in water. They have K values according to Fikentscher of 8 to 250, preferably 10 to 150 (measured in 1% by weight aqueous solution at 25 ° C. and pH 7). The joint use of hydrophilically modified polyisocyanates and polymers containing vinyl lamin units in the production of dry-strength and wet-strength finished paper gives one
Synergistischen Effekt, d.h. die Naßfestigkeit der so hergestell¬ ten Papiere liegt oberhalb der Naßfestigkeit von Papieren, zu deren Herstellung die Einzelkomponenten verwendet werden. Die erfindungsgemäß einzusetzenden Kombinationen können dem Papier- stoff vor der Blattbildung zugesetzt werden, oder auf die Ober¬ fläche eines bereits gebildeten Papierblatts aufgetragen werden. Pro Gewichtsteil von hydrophil modifizierten Polyisocyanaten verwendet man beispielsweise 0,05 bis 20, vorzugsweise 0,1 bis 5 Gewichtsteile Vinylamin-Einheiten enthaltende Polymerisate, jeweils bezogen auf den Feststoffgehalt. Die erfindungsgemäß zu verwendenden Kombinationen haben den Vorteil, daß sie praktisch nicht störstoffempfindlich sind, d.h. sie können auch in Papier¬ fabriken mit geschlossenen Wasserkreisläufen eingesetzt werden. Demgegenüber sind beispielsweise Kombinationen von hydrophil modifizierten Polyisocyanaten und Umsetzungsprodukten aus Poly- amidoaminen und/oder Polyaminen und Epichlorhydrin stark stör¬ stoffempfindlich.Synergistic effect, i.e. the wet strength of the papers thus produced is above the wet strength of papers for the manufacture of which the individual components are used. The combinations to be used according to the invention can be added to the paper stock prior to sheet formation, or applied to the surface of a paper sheet that has already been formed. Per part by weight of hydrophilically modified polyisocyanates, for example, 0.05 to 20, preferably 0.1 to 5 parts by weight of polymers containing vinylamine units are used, in each case based on the solids content. The combinations to be used according to the invention have the advantage that they are practically not sensitive to impurities, i.e. they can also be used in paper factories with closed water circuits. In contrast, combinations of hydrophilically modified polyisocyanates and reaction products of polyamidoamines and / or polyamines and epichlorohydrin, for example, are highly sensitive to impurities.
Die erfindungsgemäß zu verwendenden Kombinationen aus hydrophil modifizierten Polyisocyanaten und Vinylamin-Einheiten ent¬ haltenden Polymerisaten werden daher vorzugsweise zur Herstellung von Hygienepapieren, die nicht ausschließlich aus Frischzellstoff hergestellt werden, sondern recycelte Fasern enthalten, und bei der Herstellung von Kraftpapierqualitäten eingesetzt. Für die Herstellung von Hygienepapieren verwendet man beispielsweise Sul¬ fitzellstoffe, die als TCF- (total chlorine free) und ECF-Qualitä- ten (elemental chlorine free) bekannt sind. Bei den Kraftpapier¬ qualitäten kann man beispielsweise Sulfatzellstoffe einsetzen, die nicht so stark gewaschen sind, oder die ungebleicht oder halbgebleicht sind. Solche Sulfatzellstoffe fallen beispielsweise in integrierten Papierfabriken an, in denen Zellstoff und Papier hergestellt werden.The combinations of hydrophilically modified polyisocyanates and polymers containing vinylamine units to be used according to the invention are therefore preferred for the production of hygienic papers which are not exclusively made from fresh cellulose manufactured, but contain recycled fibers, and used in the manufacture of kraft paper. Sulphite pulps, which are known as TCF (totally chlorine free) and ECF (elemental chlorine free) qualities, are used for example for the production of hygiene papers. In the Kraft paper grades, for example, sulfate pulps can be used which are not washed as heavily or which are unbleached or half-bleached. Such sulfate pulps occur, for example, in integrated paper mills, in which pulp and paper are produced.
Die erfindungsgemäß zu verwendenden Kombinationen können gegebe¬ nenfalls zusammen mit üblichen Hilfsmitteln, wie Alkyldiketenen zur Leimung von Papier oder mit Fixiermitteln verwendet werden.The combinations to be used according to the invention can optionally be used together with customary auxiliaries, such as alkyldiketenes for sizing paper or with fixing agents.
Die Prozentangaben in den Beispielen bedeuten Gew.-%, sofern nichts anderes angegeben ist. Der K-Wert der Polymerisate wurde nach H. Fikentscher, Zellulose-Chemie, Band 13, Seiten 58 bis 64 und 71 bis 74 (1932) , bei einer Temperatur von 25°C in 5 %iger Kochsalzlösung und einer Polymerkonzentration von 0,5 Gew.-% be¬ stimmt.The percentages in the examples mean% by weight, unless stated otherwise. The K value of the polymers was determined according to H. Fikentscher, Zellulose-Chemie, Volume 13, pages 58 to 64 and 71 to 74 (1932), at a temperature of 25 ° C in 5% saline and a polymer concentration of 0.5 % By weight.
BeispieleExamples
Polymer 1Polymer 1
Homopolymerisat aus N-Vinylformamid mit einem K-Wert von 85, aus dem 95 Mol-% der Formylgruppen durch Hydrolyse mit Salzsäure ab¬ gespalten wurden, in 12 %iger wäßriger Lösung mit einem pH-Wert von 5.Homopolymer of N-vinylformamide with a K value of 85, from which 95 mol% of the formyl groups were split off by hydrolysis with hydrochloric acid, in a 12% aqueous solution with a pH value of 5.
Polymer 2Polymer 2
Hydrophil modifiziertes Polyisocyanat mit einem NCO-Gehalt von ca. 18 Gew.-%, einer Viskosität von ca. 2500 mPas, hergestellt nach Beispiel 4 der DE-A-4 036 927 durch Umsetzung eines Addukts aus 2 mol eines auf Methanol gestarteten Polyethylenoxids des Molgewichts 500 g/mol mit 1 mol Toluylendiisocyanat.Hydrophilically modified polyisocyanate with an NCO content of approx. 18% by weight, a viscosity of approx. 2500 mPas, produced according to Example 4 of DE-A-4 036 927 by reacting an adduct of 2 mol of a polyethylene oxide started on methanol Molecular weight 500 g / mol with 1 mol of tolylene diisocyanate.
Polymer 3Polymer 3
Hydrolysiertes Copolymerisat aus 70 % N-Vinylformamid und 30 % Vinylacetat, K-Wert des Polymerisats 100, Hydrolysegrad von N-Vi¬ nylformamid und Vinylacetat 90 %. Polymer 4Hydrolyzed copolymer of 70% N-vinylformamide and 30% vinyl acetate, K value of the polymer 100, degree of hydrolysis of N-vinylformamide and 90% vinyl acetate. Polymer 4
Wäßrige Lösung eines handelsüblichen neutral Naßfestharzes auf Basis eines Umsetzungsprodukts von Epichlorhydrin und einem Poly- amidoamin aus Diethylentriamin und Adipinsäure.Aqueous solution of a commercially available neutral wet strength resin based on a reaction product of epichlorohydrin and a polyamidoamine from diethylene triamine and adipic acid.
Beispiel 1example 1
Man stellte zunächst eine PapierstoffSuspension mit einer Faser- Stoffkonzentration von 0,5 % durch Eintragen einer Mischung aus 50 % Fichtensulfitzellstoff und 50 % Buchensulfitzellstoff in Wasser her. Der pH-Wert der Suspension betrug 7,8, der Mahlgrad 29° SR (Schopper-Riegler) . Diese StoffSuspension wurde in 4 glei¬ che Teile geteilt, die im Folgenden mit (a) bis (d) bezeichnet sind. Zu den StoffSuspensionen (b) bis (d) wurden die aus Ta¬ belle 1 ersichtlichen Zusätze hinzu gegeben. Anschließend wurden aus den StoffSuspensionen (a) bis (d) auf einem Rapid-Köthen-La¬ borblattbildner Blätter mit einer Flächenmasse von 80 g/m2 herge¬ stellt. Die Naßreißlänge der jeweils erhaltenen Blätter wurde in ungealtertem Zustand und nach einer Alterung von 5 Minuten bei einer Temperatur von 110°C bestimmt. Die Ergebnisse sind in Ta¬ belle 1 angegeben.A pulp suspension with a fiber concentration of 0.5% was first prepared by introducing a mixture of 50% spruce sulfite pulp and 50% beech sulfite pulp in water. The pH of the suspension was 7.8, the freeness 29 ° SR (Schopper-Riegler). This pulp suspension was divided into 4 identical parts, which are referred to below as (a) to (d). The additives shown in Table 1 were added to the substance suspensions (b) to (d). Subsequently, leaves with a basis weight of 80 g / m 2 were produced from the material suspensions (a) to (d) on a Rapid-Köthen laboratory sheet former. The wet tear length of the sheets obtained in each case was determined in the unaged condition and after aging for 5 minutes at a temperature of 110 ° C. The results are shown in Table 1.
Tabelle 1Table 1
Beispiel 1 Zusatz Naßreißlänge [m] der Blätter ungealtert gealtertExample 1 Additional wet tear length [m] of the leaves aged without aging
(5 min bei(5 min at
110°C) a) Vergleich - 110 105 b) Vergleich 1 % Polymer 1 876 854 c) Vergleich 1 % Polymer 2 914 971 d) erfindungs- 0,2 % Polymer 1 1245 1244 gemäß 0,8 % Polymer 2110 ° C) a) comparison - 110 105 b) comparison 1% polymer 1 876 854 c) comparison 1% polymer 2 914 971 d) invention 0.2% polymer 1 1245 1244 according to 0.8% polymer 2
Beispiel 2Example 2
Man stellte eine PapierstoffSuspension mit einer Konzentration von 0,5 % durch Eintragen einer Fasermischung aus 50 % Fichten¬ sulfitzellstoff und 50 % Buchensulfitzellstoff und 2 % Alaun in Wasser her. Der pH-Wert der PapierstoffSuspension betrug 4,5, der Mahlgrad 29° SR. Die StoffSuspension wurde anschließend in 4 glei¬ che Teile geteilt, zu den StoffSuspensionen (b) bis (d) wurden die aus Tabelle 2 ersichtlichen Zusätze zugegeben. Man bildete jeweils aus den so erhaltenen StoffSuspensionen auf einem Rapid- Köthen-Blattbildner Blätter mit einem Flächengewicht von 80 g/m2. Wie im Beispiel 1 angegeben, wurde die Naßreißlänge bestimmt. Die Ergebnisse sind in Tabelle 2 angegeben.A pulp suspension with a concentration of 0.5% was prepared by introducing a fiber mixture of 50% spruce sulfite pulp and 50% beech sulfite pulp and 2% alum in water. The pH of the pulp suspension was 4.5 and the freeness was 29 ° SR. The stock suspension was then divided into 4 identical parts, and the additives shown in Table 2 were added to the stock suspensions (b) to (d). In each case, sheets with a basis weight of 80 g / m 2 were formed from the material suspensions obtained in this way on a Rapid Köthen sheet former. As stated in Example 1, the wet tear length was determined. The results are shown in Table 2.
Tabelle 2Table 2
Figure imgf000016_0001
Figure imgf000016_0001
Beispiel 3Example 3
Durch Eintragen von gebleichtem Kiefernsulfatzellstoff in Wasser wurde eine 0,5 %ige StoffSuspension hergestellt. Der pH-Wert der Suspension betrug 7,5, der Mahlgrad 25° SR. Die StoffSuspension wurde anschließend in 8 gleiche Teile geteilt, wobei man zu den in Tabelle 3 unter (b) bis (h) angegebenen Suspensionen jeweils die dort beschriebenen Stoffe hinzufügte. Danach wurden aus den stoffSuspensionen (a) bis (h) in einem Rapid-Köthen-Laborblatt- bildner Blätter mit einer Flächenmasse von 80 g/m2 gebildet. Die Naßreißlängen der Blätter sind in Tabelle 3 angegeben.A 0.5% pulp suspension was prepared by adding bleached pine sulphate pulp to water. The pH of the suspension was 7.5, the freeness was 25 ° SR. The pulp suspension was then divided into 8 equal parts, the substances described there being added to the suspensions given in Table 3 under (b) to (h). Thereafter, sheets with a basis weight of 80 g / m 2 were formed from the substance suspensions (a) to (h) in a Rapid Köthen laboratory sheet former. The wet tear lengths of the leaves are given in Table 3.
Tabelle 3Table 3
Figure imgf000016_0002
Beispiel 4
Figure imgf000016_0002
Example 4
Die Beispiele 3 (b) bis (h) wurden mit der einzigen Ausnahme wiederholt, daß man im Papierstoff jeweils 1 %, bezogen auf trockenen Faserstoff, eines Gemisches aus Ligninsulfonat und Huminsäure im Gewichtsverhältnis 1:1 zusetzte. Die Ergebnisse sind in Tabelle 4 angegeben.Examples 3 (b) to (h) were repeated with the single exception that 1%, based on dry fiber, of a mixture of lignin sulfonate and humic acid in a weight ratio of 1: 1 was added to the paper stock. The results are shown in Table 4.
Tabelle 4Table 4
Figure imgf000017_0001
Figure imgf000017_0001

Claims

Patentansprüche claims
1. Verfahren zur Herstellung von trockenfest und naßfest ausge- rüstetem Papier durch Zugabe von hydrophil modifizierten1. Process for the production of dry-strength and wet-strength finished paper by adding hydrophilically modified
Polyisocyanaten und kationischen Polymeren zum Papierstoff und Entwässern des Papierstoffs unter Blattbildung oder durch Behandeln der Oberfläche von Papier mit hydrophil modifi¬ zierten Polyisocyanaten und kationischen Polymeren, dadurch gekennzeichnet, daß man als kationische Polymere Vinylamin- Einheiten enthaltende Polymerisate einsetzt.Polyisocyanates and cationic polymers for pulp and dewatering the pulp with sheet formation or by treating the surface of paper with hydrophilically modified polyisocyanates and cationic polymers, characterized in that polymers containing vinylamine units are used as cationic polymers.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß man die hydrophil modifizierten Polyisocyanaten und kationischen Polymeren jeweils in Mengen von 0,05 bis 20 Gew.-%, bezogen auf trockene Fasern, dem Papierstoff zusetzt oder auf die Oberfläche des trockenen Papiers aufträgt.2. The method according to claim 1, characterized in that the hydrophilically modified polyisocyanates and cationic polymers are each added in amounts of 0.05 to 20% by weight, based on dry fibers, of the paper stock or applied to the surface of the dry paper.
3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß man als kationische Polymere partiell oder vollständig hydrolysierte Homopolymerisate des N-Vinylformamids oder par¬ tiell oder vollständig hydrolysierte Copolymerisate des N-Vi¬ nylformamids mit Vinylformiat, Vinylacetat, Vinylpropionat, N-Vinylpyrrolidon, Acrylsäureester, Methacrylsäureester oder deren Mischungen einsetzt.3. The method according to claim 1 or 2, characterized in that partially or completely hydrolyzed homopolymers of N-vinylformamide or partially or completely hydrolyzed copolymers of N-Vi¬ nylformamids with vinyl formate, vinyl acetate, vinyl propionate, N-vinylpyrrolidone as cationic polymers , Acrylic acid esters, methacrylic acid esters or mixtures thereof.
4. Verfahren nach Anspruch 3, dadurch gekennzeichnet, daß der Hydrolysegrad des N-Vinylformamids 30 bis 100 Mol-% beträgt.4. The method according to claim 3, characterized in that the degree of hydrolysis of the N-vinylformamide is 30 to 100 mol%.
5. Verwendung von wasserdispergierbaren Polyisocyanaten in Kom¬ bination mit Vinylamin-Einheiten enthaltenden Polymerisaten als Trocken- und Naßverfestigungsmittel für Papier.5. Use of water-dispersible polyisocyanates in combination with polymers containing vinylamine units as dry and wet strength agents for paper.
6. Verwendung nach Anspruch 5, dadurch gekennzeichnet, daß man hydrophil modifizierte Polyisocyanate in Kombination mit Vi¬ nylamin-Einheiten einpolymerisiert enthaltenden Polymerisaten als Trocken- und Naßverfestigungsmittel bei der Herstellung von Hygienepapieren und Kraftpapierqualitäten einsetzt. 6. Use according to claim 5, characterized in that one uses hydrophilically modified polyisocyanates in combination with Vi¬ nylamin units polymerized containing polymers as dry and wet strength agents in the manufacture of hygienic papers and kraft paper qualities.
PCT/EP1996/004202 1995-10-05 1996-09-26 Process for producing paper with a dry-strength and wet-strength finish WO1997013033A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE1995137088 DE19537088A1 (en) 1995-10-05 1995-10-05 Process for the production of dry and wet strength paper
DE19537088.0 1995-10-05

Publications (1)

Publication Number Publication Date
WO1997013033A1 true WO1997013033A1 (en) 1997-04-10

Family

ID=7774085

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1996/004202 WO1997013033A1 (en) 1995-10-05 1996-09-26 Process for producing paper with a dry-strength and wet-strength finish

Country Status (2)

Country Link
DE (1) DE19537088A1 (en)
WO (1) WO1997013033A1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6616807B1 (en) * 1997-04-04 2003-09-09 Basf Aktiengesellschaft Method for producing high dry-strength paper, pulpboard and cardboard
US8349134B2 (en) 2004-11-23 2013-01-08 Basf Se Method for producing high dry strength paper, paperboard or cardboard
US9873986B2 (en) 2013-09-12 2018-01-23 Ecolab Usa Inc. Paper-making aid composition and process for increasing ash retention of finished paper
US9873983B2 (en) 2013-09-12 2018-01-23 Ecolab Usa Inc. Process and compositions for paper-making
CN114634610A (en) * 2022-01-26 2022-06-17 合肥科天水性科技有限责任公司 Waterborne polyurethane for paper coating and preparation method thereof

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7147751B2 (en) 2002-12-20 2006-12-12 Kimberly-Clark Worldwide, Inc. Wiping products having a low coefficient of friction in the wet state and process for producing same
US6994770B2 (en) * 2002-12-20 2006-02-07 Kimberly-Clark Worldwide, Inc. Strength additives for tissue products
CN101405457B (en) * 2006-03-16 2011-08-17 巴斯夫欧洲公司 Method for producing paper, paperboard and cardboard having high dry strength
DE102006040771B3 (en) * 2006-08-31 2008-01-31 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Preparing two-dimensional paper products with increased wet-tear stability and softness, useful e.g. as tissue paper, comprises adding block-copolymer to cellulose suspension and treating the product retroactively with the block-copolymer

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1098023A (en) * 1964-05-07 1968-01-03 American Cyanamid Co Process of strengthening paper
US4784727A (en) * 1982-01-30 1988-11-15 Bayer Aktiengesellschaft Sizing agent and use thereof
US4957977A (en) * 1986-06-25 1990-09-18 Mitsubishi Kasei Corporation Vinylamine copolymer, flocculating agent etc.
DE4036927A1 (en) * 1990-11-20 1992-05-21 Basf Ag Non-corrosive polyisocyanate preparation
WO1995031492A1 (en) * 1994-05-11 1995-11-23 Bayer Aktiengesellschaft Paper finishing aid

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1098023A (en) * 1964-05-07 1968-01-03 American Cyanamid Co Process of strengthening paper
US4784727A (en) * 1982-01-30 1988-11-15 Bayer Aktiengesellschaft Sizing agent and use thereof
US4957977A (en) * 1986-06-25 1990-09-18 Mitsubishi Kasei Corporation Vinylamine copolymer, flocculating agent etc.
EP0251182B1 (en) * 1986-06-25 1991-11-27 Mitsubishi Kasei Corporation Vinylamine copolymer, flocculating agent and paper strength increasing agent using the same, as well as process for producing the same
DE4036927A1 (en) * 1990-11-20 1992-05-21 Basf Ag Non-corrosive polyisocyanate preparation
WO1995031492A1 (en) * 1994-05-11 1995-11-23 Bayer Aktiengesellschaft Paper finishing aid

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6616807B1 (en) * 1997-04-04 2003-09-09 Basf Aktiengesellschaft Method for producing high dry-strength paper, pulpboard and cardboard
US8349134B2 (en) 2004-11-23 2013-01-08 Basf Se Method for producing high dry strength paper, paperboard or cardboard
US9873986B2 (en) 2013-09-12 2018-01-23 Ecolab Usa Inc. Paper-making aid composition and process for increasing ash retention of finished paper
US9873983B2 (en) 2013-09-12 2018-01-23 Ecolab Usa Inc. Process and compositions for paper-making
CN114634610A (en) * 2022-01-26 2022-06-17 合肥科天水性科技有限责任公司 Waterborne polyurethane for paper coating and preparation method thereof
CN114634610B (en) * 2022-01-26 2024-03-19 合肥科天水性科技有限责任公司 Water-based polyurethane for paper coating and preparation method thereof

Also Published As

Publication number Publication date
DE19537088A1 (en) 1997-04-10

Similar Documents

Publication Publication Date Title
EP0582166B1 (en) Multifuctional resins without chlorine for paper finishing
EP0207414B1 (en) Aqueous solutions or dispersions of polyisocyanate addition products, process for their preparation as well as their use as coating materials or as sizing materials for paper
DE3102038A1 (en) POLYURETHANE POLYMER AMINE SALT AS A PAPER ADDITIVE
EP0759041B1 (en) Paper finishing aid
DE3822490A1 (en) WAFER SOLUTIONS OF POLYAMIDOAMINE-EPICHLORHYRIN RESINS, PROCESS FOR THEIR PREPARATION AND THEIR USE
EP0828890B1 (en) Paper finishing process using polyisocyanates with anionic groups
EP0564912B2 (en) Paper wet-strengthening process
WO1997013033A1 (en) Process for producing paper with a dry-strength and wet-strength finish
EP0128399B1 (en) Support dressing and process for its manufacture
EP0449041B1 (en) Blends of cellulose and synthetic polymers, manufacture and uses thereof
DE4436058A1 (en) Process for the manufacture of cellulose-containing sheet materials equipped with dry and / or wet strength
EP0929588B1 (en) Water dispersable isocyanates with enhanced absorbing capacity as paper auxiliary agents
DE2505344A1 (en) PROCESS FOR THE PREPARATION OF HEAT HARDENABLE RESIN EMULSIONS
EP0799349B1 (en) Redigestible cellulose-containing marerials
EP0758417B1 (en) Use of hydrophilically modified polyisocyanates in the field of textiles
DE4419572A1 (en) Compsn. for treating cellulose material, gives improved printability and strength
DE1696280C3 (en) Paper impregnated with polymers
EP0985747B1 (en) Process for manufacturing cellulosic fibres
EP0823950B1 (en) Process for producing structurally resistant paper
DE3205966A1 (en) METHOD FOR IMPROVING THE WET STRENGTH OF PAPER
EP1070090B1 (en) Water-dispersible polyisocyanate preparations for producing repulpable paper
DE4226110A1 (en) Chlorine free multifunctional resins for paper finishing
DE19548031A1 (en) Modified cellulose material for high wet strength in non-matured state
DE1916331C3 (en) Process for finishing textile materials made of wool or fibers containing wool
DE4319571A1 (en) Chlorine-free multifunctional resins for paper finishing

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CA JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA