DE10322267A1 - Packaging material, useful for liquids and beverages, comprises an at least two layer laminate of paper or card sized with a polymer sizing agent and at least one water-impermeable film - Google Patents

Abstract

A packaging material comprises an at least two layer laminate comprising sized paper or card and at least one water-impermeable film for the production of packaging for liquids whereby the paper or card is sized with a polymer sizing agent.

Description

The The invention relates to a packaging material comprising at least one two-layer composite made of glued paper or glued cardboard and at least one waterproof film for the packaging of liquids and the use of paper products that are glued in bulk and the one or both sides with a film made of a plastic or laminated metal to make containers for packaging of liquids, especially of beverages.

Out EP-B-O 292 975 is the use of an emulsion of an alkyl ketene dimer in combination with a cationic resin glue and an insolubilizing Means such as alum, for the production of cardboard for the packaging of liquids known. The carton is made by adding the sizing agent and alum to an aqueous slurry of Cellulose fibers and dewatering of the paper stock on a sieve.

Out EP-A-1 091 043 is a process for producing a coated Packing boxes are known, wherein an aqueous slurry of Bulk cellulose fibers with an aqueous dispersion of resin glue, a synthetic sizing agent such as alkyl ketene dimer and at least an aluminum compound and the aqueous slurry drained from a sieve. The watery Dispersions of the shell size agents may optionally be a dispersant included, e.g. cationic starch, casein, Cellulose derivatives, polyvinyl alcohols, polyacrylamides or polyethyleneimines. The box is usually following and the sizing coated.

both sides with a liquid impermeable layer laminated paper products for the packaging of foods is known from WO-A-02/090206. The paper products are bulk with aqueous dispersions of alkyl ketene dimers glued. The amount of alkyl ketene dimers is at least 0.25% by weight, preferably 0.25-0.4 % By weight, based on the weight of the dry paper products.

Further multilayer packaging materials, the base layer of paper or cardboard, are described, for example, in WO-A-97/02140, WO-A-97/02181 and WO-A-98/18680 described.

Out is also state of the art known, sizing mixtures from aqueous dispersions of alkyl ketene dimers and polymer sizing agents for mass sizing paper and cardboard to use, cf. DE-A-32 35 529, WO-A-94/05855 and WO-A-96/31650.

Out the older DE application 10237913.0 is a process for the production of cardboard for the Packaging of liquids known. In this process, the box is made by mass gluing an aqueous slurry of cellulose fibers with at least one bulk sizing agent in Presence of at least one retention agent and at least one cationic polymers and optionally a water-soluble Aluminum connection and drainage of the paper stock on a sieve. As a sizing agent alkyl ketene dimers, alkyl and alkenyl succinic anhydrides, Alkyl isocyanates, combinations of resin glue and alum and combinations from reaction products of resin glue with carboxylic acid anhydrides and alum.

The The present invention is based on the object of further packaging materials to provide on the basis of paper products, the Packaging in particular improved edge penetration and have an improved adhesion of the laminates to paper or cardboard should.

The The object is achieved with a Packaging material made of at least a two-layer composite made of glued paper or glued cardboard and at least one impermeable Foil for the production of containers for the Packaging of liquids, if the paper or cardboard is in bulk with a polymer sizing agent is glued.

The invention also relates to the use of paper products which are each obtainable from
Bulk sizing of a paper stock from an aqueous slurry of cellulose fibers with at least one polymer sizing agent as bulk sizing agent or with a polymer sizing agent and an aqueous dispersion of an alkyl ketene dimer or mixtures thereof in the presence of a retention aid and optionally a water-soluble aluminum compound and optionally at least one cationic polymer,
Dewatering the pulp on a paper machine screen, drying the paper product and
laminating the paper product on one or both sides with a film made of plastic or metal,
for the production of containers for the packaging of liquids, in particular beverages.

For the production of glued paper or glued cardboard you can all, usually Use cellulose fibers used in the paper industry, e.g. Fibers from wood pulp and all annual plants. Under wood pulp one understands, for example, ground wood, thermomechanical material (TMP), chemothermomechanical material (CTMP), pressure grinding, semi-pulp, High yield pulp, refiner mechanical pulp (RMP) and waste paper. Moreover are suitable pulps that are bleached or unbleached Shape can be used. Examples of this are sulfate, sulfite and Natronzellstoffe. Unbleached cellulose is preferably used, which are also known as unbleached kraft pulp. The Fibers can used alone or in a mixture with each other.

at The mass gluing of paper or cardboard is done during the Manufacturing process of these materials by going to paper stock a so-called bulk sizing agent and puts it on the sieve dewatered in a paper machine with sheet formation. According to the invention is considered Bulk sizing agent is a polymer sizing agent made from synthetic Polymers used. In the polymer sizing agents known from JP-A-58/115 196 it is watery Polymer dispersions that are a sizing agent for paper and at the same time increase the strength of paper. These dispersions are made by polymerizing, for example Styrene and alkyl acrylates in the presence of starch and free radicals Polymerization initiators in aqueous Medium made. The starch used in each case is digested before the polymerization or broken down so that they soluble in water is. The polymers of these dispersions are graft polymers of Styrene and alkyl acrylates on starch or modified strength.

Further polymer sizing agents are known from EP-B-0 257 412 and EP-B-0 267 770. They are obtained by copolymerizing acrylonitrile and / or methacrylonitrile and at least one acrylic acid ester of a monohydric, saturated C ₃ to C ₈ alcohol in the manner of an emulsion polymerization in an aqueous solution which contains a degraded starch in the presence of free radical initiators, preferably hydrogen peroxide or redox initiators. The mined starches have viscosities n; from 0.04 to 0.50 dl / g. Such starches are obtained, for example, in the case of oxidative, thermal, acidolytic or enzymatic degradation of a native, cationically or anionically modified starch. Native starches from potatoes, wheat, corn are advantageous. Rice or tapioca used. An enzymatically degraded potato starch is preferred. The degraded starches act as emulsifiers in the copolymerization of, for example, styrene and n-butyl acrylate in an aqueous medium. The aqueous solution in which the copolymerization is carried out contains, for example, 1 to 25% by weight of at least one degraded starch. In 100 parts by weight of such a solution, for example, 10 to 150, preferably 40 to 100 parts by weight of the above-mentioned monomers are polymerized. Instead of acrylonitrile and / or methacrylonitrile, styrene can also be used in the copolymerization, cf. WO-A-94 / 05,855th Aqueous dispersions of copolymers with an average particle diameter of, for example, 50 to 500 nm, preferably 100 to 300 nm, are obtained. These polymer dispersions are presumably graft polymers of the monomers used in each case on degraded starch.

Further polymer sizing agents based on copolymers of styrene and C ₃ -C ₈ -alkyl (meth) acrylates are known from WO 02/14393. They are prepared by copolymerizing the monomers mentioned in an aqueous medium in the presence of degraded starch and radical-forming polymerization initiators using a two-stage process.

• (a) Styrol, Acrylnitril und/oder Methacrylnitril,
• (b) Acrylsäure- und/oder Methacrylsäureester von C₁- bis C₁₈-Alkoholen und/oder Vinylester von gesättigtem C₂- bis C₄-Carbonsäuren und ggf.
• (c) anderen monoethylenisch ungesättigten copolymerisierbaren Monomeren

in wäßriger Lösung in Gegenwart von 1 Gew.-Teil eines Lösungscopolymerisats aus

• (1) Di-C₁- bis C₄-Alkylamino-C₂- bis C₄-Alkyl(meth)acrylaten, die ggf. protoniert oder quaterniert sein können,
• (2) nichtionischen, hydrophoben, ethylenisch ungesättigten Monomeren, bei diesen Monomeren, wenn sie für sich alleine polymerisiert werden, hydrophobe Polymerisate bilden und ggf.
• (3) monoethylenisch ungesättigten C₃- bis C₅-Carbonsäuren oder ihren Anhydriden, wobei das Molverhältnis von (1) : (2) : (3) = 1 : 2,5 bis 10 : 0 bis 1,5 beträgt, copolymerisiert.

Aqueous polymer dispersions which can be prepared in the presence of synthetic polymeric protective colloids are also suitable as polymer sizing agents. They can be obtained, for example, by copolymerizing 2 to 32 parts of a mixture of

• (a) styrene, acrylonitrile and / or methacrylonitrile,
• (b) acrylic and / or methacrylic acid esters of C ₁ to C ₁₈ alcohols and / or vinyl esters of saturated C ₂ to C ₄ carboxylic acids and optionally
• (c) other monoethylenically unsaturated copolymerizable monomers

in aqueous solution in the presence of 1 part by weight of a solution copolymer

• (1) di-C ₁ -C ₄ -alkylamino-C ₂ -C ₄ -alkyl (meth) acrylates, which may optionally be protonated or quaternized,
• (2) nonionic, hydrophobic, ethylenically unsaturated monomers, in the case of these monomers, if they are polymerized on their own, form hydrophobic polymers and, if appropriate,
• (3) monoethylenically unsaturated C ₃ to C ₅ carboxylic acids or their anhydrides, the molar ratio nis of (1): (2): (3) = 1: 2.5 to 10: 0 to 1.5, copolymerized.

A solution copolymer is first prepared by copolymerizing the monomers of groups (1) and (2) and, if appropriate, (3) in a water-miscible organic solvent. Suitable solvents are, for example, C ₁ to C ₃ carboxylic acids, such as formic acid, acetic acid and propionic acid, or C ₁ to C ₄ alcohols, such as methanol, ethanol, n-propanol or isopropanol, and ketones such as acetone. The group (1) monomers used are preferably dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminopropyl methacrylate and dimethylaminopropyl acrylate. The monomers of group (1) are preferably used in protonated or quaternized form. Suitable quaternizing agents are, for example, methyl chloride, dimethyl sulfate or benzyl chloride.

The group (2) monomers used are nonionic, hydrophobic, ethylenically unsaturated compounds which, when polymerized on their own, form hydrophobic polymers. These include, for example, styrene, methylstyrene, C ₁ - to C ₁₈ -alkyl esters of acrylic acid or methacrylic acid, for example methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate and isobutyl acrylate as well as isobutyl methacrylate, n-butyl methacrylate and n-butyl methacrylate , Acrylonitrile, methacrylonitrile, vinyl acetate, vinyl propionate and vinyl butyrate are also suitable. Mixtures of the group 2 monomers can also be used in the copolymerization, for example mixtures of styrene and isobutyl acrylate. The solution copolymers used as emulsifiers may optionally also contain copolymerized monomers of group (3), for example monoethylenically unsaturated C ₃ to C ₅ carboxylic acids or their anhydrides, for example acrylic acid, methacrylic acid, itaconic acid, maleic acid, maleic anhydride or itaconic anhydride. The molar ratio of (1): (2): (3) is 1: 2.5 to 10: 0 to 1.5. The copolymer solutions thus obtained are diluted with water and, in this form, serve as a protective colloid for the polymerization of the above-mentioned monomer mixtures of components (a) and (b) and, if appropriate, (c). Monomers of group (a) are styrene, acrylonitrile, methacrylonitrile or mixtures of styrene and acrylonitrile or of styrene and methacrylonitrile. The monomers of group (b) used are acrylic acid and / or methacrylic acid esters of C ₁ to C ₁₈ alcohols and / or vinyl esters of saturated C ₂ to C ₄ carboxylic acids. This group of monomers corresponds to the monomers of group (2), which has already been described above. Preferably used as the monomer of group (b) are butyl acrylate and butyl methacrylate, for example isobutyl acrylate, n-butyl acrylate and isobutyl methacrylate. Monomers of group (c) are, for example, C ₃ - to C ₅ -monoethylenically unsaturated carboxylic acids, acrylamidomethylpropanesulfonic acid, sodium vinyl sulfonate, vinylimidazole, N-vinylformamide, acrylamide, methacrylamide and N-vinylimidazoline. 1 to 32 parts by weight of a monomer mixture of components (a) to (c) are used per 1 part by weight of the copolymer. The monomers of components (a) and (b) can be copolymerized in any ratio, for example in the molar ratio 0.1: 1 to 1: 0.1.

The Monomers of group (c) are used for modification if necessary the properties of the copolymers used.

sizing agents of this type are described, for example, in EP-B-0 051 144, EP-B-0 058 313 and EP-B-0 150 003.

Aqueous polymer dispersions which are obtained by copolymerizing
20 to 65% by weight of styrene, acrylonitrile and / or methacrylonitrile,
80 to 35 wt .-% acrylic acid and / or methacrylic acid esters of monohydric saturated C ₃ to C ₈ alcohols and
0 to 20% by weight of other monoethylenically unsaturated copolymerizable monomers such as acrylamide, methacrylamide, vinylformamide, acrylic acid, methacrylic acid, maleic acid, itaconic acid, 2-acrylamido-2-methylpropanesulfonic acid or basic monomers such as dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminopropylacrylate methacrylate or monoethyl acrylate, are mostly used as hydrochlorides or in a quaternized form with methyl chloride, dimeethyl sulfate or benzyl chloride,
are available as protective colloid in the presence of free radical initiators in the manner of an emulsion polymerization in an aqueous solution of a degraded starch.

Furthermore, aqueous polymer dispersions which are obtained by copolymerizing
60 to 90% by weight of styrene and / or methylstyrene,
10 to 40 wt .-% 1,3-butadiene and / or isoprene and
0 to 20% by weight of other monoethylenically unsaturated copolymerizable monomers such as acrylic acid, methacrylic acid, itaconic acid, acrylamide, methacrylamide or N-vinylpyrrolidone,
are available as protective colloid in the presence of free radical initiators in the manner of an emulsion polymerization in an aqueous solution of a degraded starch.

The Polymer sizing agents are preferably cationic or anionic. The charge of the aqueous dispersions is based either on the type of polymerized into the copolymers Comonomers, e.g. when using basic monomers Polymer sizing agent dispersion cationic while being polymerized of, for example, acrylic acid or their salts becomes anionic, or on the charge of the respective protective colloid used. So leads for example the use of cationic starch as Emulsifier for cationic polymer size dispersions.

For mass sizing of paper or cardboard is used, for example, 0.1 to 2.0, preferably 0.2 to 0.75% by weight polymer sizing agent (i.e. 100% polymer), based on dry paper product.

The mass sizing of paper and cardboard can additionally in the presence of aqueous dispersions of reactive sizing agents such as alkyl ketene dimers, C ₅ - to C ₂₂ alkyl and / or C ₅ - to C ₂₂ alkenyl succinic anhydrides, chloroformic acid esters and C ₁₂ - to C ₃₆ alkyl isocyanates as well in the presence of combinations of resin glue and alum or of combinations of reaction products of resin glue with carboxylic anhydrides and alum. Instead of alum or in combination with alum, other aluminum-containing compounds such as polyaluminium chlorides or the polyaluminium compounds known from EP-B-1 091 043 can be used.

Of the reactive sizing agents, C ₁₂ to C ₂₂ alkyl ketene dimers are preferably used, for example stearyldiketene, lauryldiketene, palmityldiketene, oleyldiketene, behenyldiketene or mixtures thereof.

suitable succinic are e.g. decenylsuccinic, octenyl succinic anhydride, dodecenylsuccinic and n-hexadecenyl succinic anhydride.

The Reactive sizes are common in the form of an aqueous Dispersion used. For example, alkyl ketene dimers are dispersed in an aqueous solution a cationic strength or nonionic or anionic emulsifiers are used Stabilization of the alkyl ketene dimers. Depending on the type and amount of used emulsifiers or mixtures of mutually compatible Emulsifiers are the resulting reactive size dispersions cationic, neutral or anionic.

For example, anionic emulsifiers can be added to alkyl ketene dimer dispersions which have been emulsified in water with the aid of cationic starch. If the charge of the anionic emulsifiers outweighs the charge of the cationic emulsifiers, an anionically charged alkyl ketene dimer dispersion is obtained. Anionically charged aqueous alkyldiketene dispersions are preferably prepared by emulsifying alkylketene dimers in aqueous solutions of anionic emulsifiers. Anionic emulsifiers which can be used are, for example, condensates of naphthalenesulfonic acid and formaldehyde, sulfonated polystyrene, C ₁₀ -C ₂₂ -alkylsulfuric acids, ligninsulfonic acid, phenolsulfonic acid, naphthalenesulfonic acid or the sodium, potassium or ammonium salts of the acids mentioned. Copolymers of acrylic acid and maleic acid, homopolymers of acrylic acid, homopolymers of methacrylic acid, copolymers of isobutene and maleic acid and / or acrylic acid, hydrolyzed copolymers of isobutene or diisobutene and maleic anhydride are suitable emulsifiers for the preparation of anionic alkyl ketene dimer dispersions. The acid groups of the homopolymers and copolymers can, for example, be partially or completely neutralized with sodium hydroxide solution, potassium hydroxide solution or with ammonia and used in this form as anionic emulsifiers. The molecular weight M _{w of} the homo- and copolymers is, for example, 1000 to 15000 and is preferably in the range from 1500 to 10000. The emulsifiers are used, for example, in amounts of up to 3.5% by weight, preferably up to 2% by weight. , based on the reactive size to be dispersed.

The reactive sizing agents are optionally used in the mass sizing of the paper products to be used according to the invention as carrier material for the packaging materials. They are used particularly when packaging materials with particularly good edge penetration are required. They are then used in amounts which are usually required for the production of sized paper products, for example 0.1 to 2.0, preferably 0.1 to 0.5% by weight, based on dry cellulose fibers. Per 100 parts by weight of polymer sizing agent, for example 0 to 90 parts by weight, preferably 50 to 90 parts by weight, of reactive sizing agents are used. If one mixes from a polymer sizing dispersion one and an aqueous dispersion of a reactive sizing agent, the mixtures each contain, based on the polymer content, for example 5 to 50, preferably 10 to 30% by weight of polymer (100%).

Provided Reactive sizing agent used together with a polymer sizing agent be, the reactive sizes, preferably alkyl ketene dimer dispersions, first to Add paper stock and then meter the polymer size dispersions. However, one can also use the alkyl ketene dimer dispersion and at least a polymer size dispersion simultaneously with the paper stock inflict and then drain it to form leaves or a mixture of a reactive sizing agent such as at least one alkyl ketene dimer dispersion and at least one Polymer sizing agent dispersion to the paper stock and dewatered it thereafter with leaf formation.

The Polymer sizing agents can Of course also as a surface sizing agent used by e.g. with the help of a size press to the surface of the paper or sprayed onto the surface of the paper.

The Drain of the paper stock takes place additionally in the presence of a retention aid. In addition to anionic retention aids or nonionic retention agents such as polyacrylamides prefers cationic polymers as retention and drainage aids used. This will significantly improve runnability of paper machines. Can be used as a cationic retention agent one all for that in Commercially available Use products. These are, for example, cationic polyacrylamides, Polydiallyldimethylammoniumchloride, Polyethylenimine, Polyamine With a molecular weight of more than 50,000, polyamines, which if necessary are modified by grafting ethyleneimine, polyetheramides, Polyvinylimidazoles, polyvinylpyrrolidines, polyvinylimidazolines, Polyvinyltetrahydropyrins, poly (dialkylaminoalkyl vinyl ether), poly (dialkylaminoalkyl (meth) acrylates) in protonated or quaternized form and around polyamidoamines from a dicarboxylic acid like adipic acid and polyalkylene polyamines such as diethylene triamine amine which are mixed with ethylene imine grafted and with polyethylene glycol dichlorohydrin ethers according to the teaching DE-B-24 34 816 are cross-linked or to polyamidoamines, which with epichlorohydrin too water-soluble Condensation products are implemented and copolymers of Acrylamide or methacrylamide and dialkylaminoethyl acrylates or methacrylates, for example copolymers of acrylamide and Dimethylaminoethyl acrylate in the form of the salt with hydrochloric acid or in a quaternized form with methyl chloride. Other suitable retention aids are so-called microparticle systems made from cationic polymers like cationic starch and finely divided silica or from cationic polymers such as cationic polyacrylamide and Bentonite.

The cationic polymers that are used as retention aids, have, for example, Fikentscher K values of at least 140 (determined in 5% aqueous saline solution a polymer concentration of 0.5 wt.%, a temperature of 25 ° C and a pH of 7). They are preferably used in amounts of 0.01 to 0.3 % By weight, based on dry cellulose fibers.

To the aqueous slurry of Cellulose fibers can optionally be added to those already mentioned Add at least one cationic polymer to the substances. Examples for cationic Polymers are polymers containing vinylamine units, vinylguanidine units containing polymers, dialkylamino alkyl (meth) acrylamide units containing polymers, polyethyleneimines, grafted with ethyleneimine Polyamidoamines and / or polydiallyldimethylammonium chlorides. The The amount of cationic polymers is, for example, 0.001 to 2.0 wt .-%, preferably 0.01 to 0.1 wt .-%, based on dry Cellulose fibers.

Vinylamine units containing polymers are known, cf. US-A-4,421,602, US-A-5,334,287, EP-A-0 216,387, US-A-5,981,689, WO-A-00/63295 and US-A-6,121,409. you will be by hydrolysis of open-chain containing N-vinylcarboxamide units Polymers. These polymers are e.g. available through Polymerizing N-vinylformamide, N-vinyl-N-methylformamide, N-vinylacetamide, N-vinyl-N-methylacetamide, N-vinyl-N-ethyl acetamide and N-vinyl propionamide. The monomers mentioned can either polymerized alone or together with other monomers.

Suitable monoethylenically unsaturated monomers which are copolymerized with the N-vinylcarboxamides are all compounds which can be copolymerized therewith. Examples include vinyl esters of saturated carboxylic acids of 1 to 6 carbon atoms, such as vinyl formate, vinyl acetate, vinyl propionate and vinyl butyrate, and vinyl ethers, such as C ₁ -C ₆ -alkyl vinyl ether, for example methyl or ethyl vinyl ether. Other suitable comonomers are esters, amides and nitrites of ethylenically unsaturated C ₃ to C ₆ carboxylic acids, for example methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate, acrylamide and methacrylamide, and acrylonitrile and methacrylonitrile.

Further suitable carboxylic acid esters are derived from glycols or polyalkylene glycols, respectively only one OH group is esterified, e.g. Hydroxyethyl acrylate, hydroxyethyl methacrylate, Hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxypropyl methacrylate, Hydroxybutyl methacrylate and acrylic acid monoesters of polyalkylene glycols a molecular weight of 500 to 10,000. Other suitable comonomers are Esters of ethylenically unsaturated carboxylic acids with amino alcohols such as dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, Diethylaminoethyl acrylate, diethylaminoethyl methacrylate, dimethylaminopropyl acrylate, Dimethylaminopropyl methacrylate, diethylaminopropyl acrylate, dimethylaminobutyl acrylate and diethylaminobutyl acrylate. The basic acrylates can be used in Form of the free bases, the salts with mineral acids such as hydrochloric acid, sulfuric acid or Nitric acid, of salts with organic acids like formic acid, Acetic acid, propionic or the sulfonic acids or used in quaternized form. Suitable quaternizing agents are, for example, dimethyl sulfate, diethyl sulfate, methyl chloride, Ethyl chloride or benzyl chloride.

Further suitable comonomers are amides of ethylenically unsaturated carboxylic acids such as acrylamide, methacrylamide and N-alkyl mono- and diamides from monoethylenically unsaturated carboxylic acids with alkyl residues of 1 to 6 carbon atoms, e.g. N-methyl acrylamide, N, N-dimethylacrylamide, N-methyl methacrylamide, N-ethyl acrylamide, N-propylacrylamide and tert-butyl acrylamide as well as basic (meth) acrylamides, e.g. dimethylaminoethyl, Dimethylaminoethyl methacrylamide, diethylaminoethyl acrylamide, diethylaminoethyl methacrylamide, Dimethylaminopropylacrylamide, diethylaminopropylacrylamide, dimethylaminopropylmethacrylamide and diethylaminopropyl methacrylamide.

Farther are suitable as comonomers N-vinylpyrrolidone, N-vinylcaprolactam, Acrylonitrile, methacrylonitrile, N-vinylimidazole and substituted N-vinylimidazoles such as e.g. N-vinyl-2-methylimidazole, N-vinyl-4-methylimidazole, N-vinyl-5-methylimidazole, N-vinyl-2-ethylimidazole and N-vinylimidazolines such as N-vinylimidazoline, N-vinyl-2-methylimidazoline and N-vinyl-2-ethylimidazoline. N-vinylimidazoles and N-vinylimidazolines except in the form of the free bases also in neutralized or with mineral acids or organic acids used in quaternized form, the quaternization being preferred with dimethyl sulfate, diethyl sulfate, methyl chloride or benzyl chloride is made. Diallyldialkylammonium halides are also suitable such as. Diallyl dimethyl ammonium chloride.

• – 95 bis 5 mol-%, vorzugsweise 90 bis 10 mol% mindestens eines N-Vinylcarbonsäureamids und
• – 5 bis 95 mol-%, vorzugsweise 10 bis 90 mol-% andere, damit copolymerisierbare monoethylenisch ungesättigte Monomere in einpolymerisierter Form. Die Comonomeren sind vorzugsweise frei von Säuregruppen.

The copolymers contain, for example

• - 95 to 5 mol%, preferably 90 to 10 mol% of at least one N-vinylcarboxamide and
• - 5 to 95 mol%, preferably 10 to 90 mol% of other monoethylenically unsaturated monomers copolymerizable therewith in copolymerized form. The comonomers are preferably free from acid groups.

• – N-Vinylformamid mit
• – Vinylformiat, Vinylacetat, Vinylpropionat, AcRYlnitril, N-Vinylcaprolactam, N-Vinylharnstoff, N-Vinylpyrrolidon oder C₁- bis C₆-Alkylvinylethern

In order to prepare polymers containing vinylamine units, one preferably starts from homopolymers of N-vinylformamide or from copolymers which are obtained by copolymerizing

• - N-vinylformamide with
• - Vinyl formate, vinyl acetate, vinyl propionate, acRYL nitrile, N-vinyl caprolactam, N-vinyl urea, N-vinyl pyrrolidone or C ₁ - to C ₆ -alkyl vinyl ethers

and subsequent Hydrolysis of the homopolymers or copolymers to form vinylamine units are available from the polymerized N-vinylformamide units, the degree of hydrolysis e.g. 5 to 100 mol%, preferably 70 to Is 100 mol%. The hydrolysis of the polymers described above is carried out according to known ones Procedures by exposure to acids, Bases or enzymes. When using acids as hydrolysis agents the vinylamine units of the polymers as ammonium salt, while at the hydrolysis with bases the free amino groups are formed.

In most cases, the degree of hydrolysis of the homo- and copolymers is 80 to 95 mol%. The degree of hydrolysis of the homopolymers is synonymous with the vinylamine units in the polymers. In the case of copolymers which contain vinyl esters in copolymerized form, in addition to the hydrolysis of the N-vinylformamide units, hydrolysis of the ester groups can occur with formation of vinyl alcohol units. This is particularly the case if the copolymers are hydrolysed in the presence of sodium hydroxide solution. Polymerized acrylonitrile is also chemically changed during the hydrolysis. This creates, for example, amide groups or carboxyl groups. The homo- and copolymers containing vinylamine units may optionally contain up to 20 mol% of amidine units which are formed, for example, by reaction of formic acid with two adjacent amino groups or by intramolecular reaction of an amino group with an adjacent amide group, for example of polymerized N-vinylformamide. The molecular weights M _{w of} the polymers containing vinylamine units are, for example, 500 to 10 million, preferably 1000 to 5 million (determined by light scattering). This molar mass range corresponds, for example, to K values of 5 to 300, preferably 10 to 250 (determined according to H. Fikentscher in 5% aqueous sodium chloride solution at 25 ° C. and a polymer concentration of 0.5% by weight).

The Polymers containing vinylamine units are preferably used in salt-free form used. Salt-free aqueous solutions of vinylamine units containing polymers for example from the salt-containing polymer solutions described above With the help of ultrafiltration on suitable membranes at separation limits for example 1000 to 500,000 daltons, preferably 10,000 up to 300,000 daltons. Also the ones described below aqueous solutions of amino and / or Other polymers containing ammonium groups can be ultrafiltration can be obtained in salt-free form.

Derivatives of polymers containing vinylamine units can also be used as cationic polymers. For example, it is possible to produce a large number of suitable derivatives from the polymers containing vinylamine units by amidation, alkylation, sulfonamide formation, urea formation, thiourea formation, carbamate formation, acylation, carboxymethylation, phosphonomethylation or Michael addition of the amino groups of the polymer. Of particular interest here are uncrosslinked polyvinylguanidines which are obtained by reacting polymers containing vinylamine units, preferably polyvinylamines, with cyanamide (R ¹ R ² N-CN, where R ¹ , R ² = H, C ₁ - to C ₄ -alkyl, C ₃ - to C ₆ -cycloalkyl, phenyl, benzyl, alkyl-substituted phenyl or naphthyl) are accessible, cf. US-A-6,087,448, column 3, line 64 to column 5, line 14.

To the polymers containing vinylamine units also belong hydrolyzed graft polymers of, for example, N-vinylformamide on polyalkylene glycols, polyvinyl acetate, polyvinyl alcohol, polyvinylformamides, Polysaccharides like starch, Oligosaccharides or monosaccharides. The graft polymers are available through that he for example, N-vinylformamide in an aqueous medium in the presence if necessary together at least one of the graft bases mentioned radically polymerized with copolymerizable other monomers and then the grafted vinylformamide units in known hydrolyzed to vinylamine units.

As Cationic polymers also come from dialkylaminoalkyl (meth) acrylamides into consideration. Suitable monomers for the production of such polymers are, for example, dimethylaminoethyl acrylamide, dimethylaminoethyl methacrylamide, Dimethylaminopropylacrylamide, dimethylaminopropylmethacrylamide, Diethylaminoethyl acrylamide, diethylaminoethyl methacrylamide and diethylaminopropylacrylamide. This Monomers can in the form of the free bases, the salts with inorganic or organic Acids or be used in quaternized form in the polymerization. You can to homopolymers or together with other copolymerizable Monomers to copolymers are radically polymerized. The Polymers contain, for example, at least 30 mol%, preferably at least 70 mol% of the basic monomers mentioned are copolymerized.

Further Suitable cationic polymers are polyethyleneimines, for example by polymerization of ethyleneimine in aqueous solution in the presence of acid-releasing agents Compounds, acids or Lewis acids can be produced as a catalyst. For example, polyethyleneimines Molar masses up to 2 million, preferably from 200 to 1,000,000. Polyethyleneimines with molecular weights of 500 are particularly preferred used up to 750,000. The polyethyleneimines can optionally be modified e.g. alkoxylated, alkylated or amidated. You can also choose one Michael addition or a connector synthesis. The thereby available Derivatives of polyethyleneimines are also available as cationic polymers suitable.

Polyamidoamines grafted with ethyleneimine are also suitable, which can be obtained, for example, by condensing dicarboxylic acids with polyamines and then grafting ethyleneimine. Suitable polyamidoamines are obtained, for example, by reacting dicarboxylic acids having 4 to 10 carbon atoms with polyalkylene polyamines which contain 3 to 10 basic nitrogen atoms in the molecule. Examples of dicarboxylic acids are succinic acid, maleic acid, adipic acid, glutaric acid, suberic acid, sebacic acid or terephthalic acid. Mixtures of dicarboxylic acids can also be used in the preparation of the polyamidoamines, as can mixtures of several polyalkylene polyamines. Suitable polyalkylene polyamines are, for example, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenetriamine, tripropylenetetramine, dihexamethylenetriamine, aminopropylethylenediamine and bis-aminopropylethylenediamine. The dicarboxylic acids and polyalkylene polyamines are heated to higher temperatures to produce the polyamidoamines, for example to temperatures in the range from 120 to 220, preferably 130 to 180 ° C. The water generated during the condensation is removed from the system. Lactones or lactams of carboxylic acids having 4 to 8 carbon atoms can optionally also be used in the condensation. For example, 0.8 to 1.4 moles of a polyalkylene polyamine are used per mole of a dicarboxylic acid. These polyamidoamines are grafted with ethyleneimine. The grafting reaction is carried out, for example, in the presence of acids or Lewis acids such as sulfuric acid or boron trifluoride etherates at temperatures of, for example, 80 to 100.degree. Compounds of this type are described for example in DE-B-24 34 816.

The optionally crosslinked polyamidoamines, which are optionally additionally grafted with ethyleneimine before crosslinking, are also suitable as cationic polymers. The crosslinked polyamidoamines grafted with ethyleneimine are water-soluble and have, for example, an average molecular weight M _w of 3000 to 2 million daltons. Typical crosslinkers are, for example, epichlorohydrin or bischlorohydrin ethers of alkylene glycols and polyalkylene glycols.

As cationic polymers are also suitable for polyallylamines. polymers of this type are obtained by homopolymerizing allylamine, preferably in with acids neutralized form or by copolymerizing allylamine with other monoethylenically unsaturated Monomers described above as comonomers for N-vinyl carboxamides.

Also suitable are water-soluble crosslinked polyethyleneimines which are obtainable by reacting polyethyleneimines with crosslinkers such as epichlorohydrin or bischlorohydrin ethers of polyalkylene glycols having 2 to 100 ethylene oxide and / or propylene oxide units and still have free primary and / or secondary amino groups. Amidic polyethyleneimines which are obtainable, for example, by amidating polyethyleneimines with C ₁ -C ₂₂ -monocarboxylic acids are also suitable. Other suitable cationic polymers are alkylated polyethyleneimines and alkoxylated polyethyleneimines. In alkoxylation, for example, 1 to 5 ethylene oxide or propylene oxide units are used per NH unit in the polyethyleneimine.

The The above-mentioned cationic polymers have e.g. K values of 8 to 300, preferably 15 to 180 (determined according to H. Fikentscher in 5% aqueous Saline at 25% and a polymer concentration of 0.5% by weight). At a For example, pH 4.5 they have a charge density of at least 1, preferably at least 4 meq / g polyelectrolyte.

Cationic polymers which are preferred are polymers containing vinylamine units and polyethyleneimines. Examples for this are:
Vinylamine homopolymers, 10 to 100% hydrolyzed polyvinylformamides, partially or completely hydrolyzed copolymers of vinylformamide and vinyl acetate, vinyl alcohol, vinylpyrrolidone or acrylamide, each with molecular weights from 3,000 to 2,000,000 and
Polyethyleneimines, crosslinked polyethyleneimines or amidated polyethyleneimines, each of which has a molecular weight of 500 to 3,000,000.

The The polymer content of the aqueous solution is, for example 1 to 60, preferably 2 to 15 and mostly 5 to 10% by weight.

The Cardboard is usually produced by draining a slurry of cellulose fibers. The use of kraft pulp is preferred. The use of TMP and CTMP is also of particular interest. The pH of the cellulose fiber slurry is, for example, 4 to 8, preferably 6 to B. The drainage of the paper stock can be discontinuous or continuous a paper machine. The order of addition of cationic polymer, bulk sizing agent and retention aid can be chosen arbitrarily become. However, preference is given to a procedure in which the aqueous cellulose fiber slurry first Retention agent and then the cationic polymer, preferably Polyvinylamine, and then at least one reactive sizing agent such as alkyl ketene dimer, alkyl or alkenyl succinic anhydride in combination with an aluminum compound or a mixture this mass sizing agent and a polymer sizing agent are added. According to one another embodiment will first at least one polymer sizing agent, then the retention aid and finally metered the cationic polymer.

at the production of the paper products to be used according to the invention you can do others, usually also use suitable aids, e.g. Fixer, Dyes, bactericides and dry and / or wet strength agents for paper.

After dewatering the paper stock and drying the paper product, you get one in the Mass glued cardboard with a basis weight of 80 to 400 g / m ² , preferably 120 to 220 g / m ² . The box is coated on one or both sides with a film made of plastic or metal such as aluminum. Suitable plastic films can be made from polyethylene, polypropylene, polyamide or polyester. For example, the foils can be bonded to the glued paper products using an adhesive. In such cases, films are usually used, which are coated with an adhesive, and the composite is pressed. However, one can also coat the surface of the paper products with an adhesive and then apply the films on one or both sides and press the resulting composite. However, the films can also be processed directly by the action of heat and pressure with the cardboard to form a composite, from which the suitable structures for the production of the packaging for liquids are then cut out. The packaging is preferably used in the food sector, for example for packaging drinks such as mineral water, juices or milk or for producing drinking vessels such as cups. It is important with these packages that they have good edge penetration, ie the box should absorb as little or practically no liquid. The adhesion of foils to paper products sized with polymer sizing agents is better than that of foils to paper products sized exclusively with alkyl ketene dimers.

Unless the context indicates otherwise, the percentages in the examples mean percent by weight. The K values were according to N. Fikentscher, Cellulose-Chemie, Vol. 13, 58-64 and 71-74 (1932) in 5% aqueous saline solution at a temperature of 25 ° C and a pH of 7 at a Polymer concentration of 0.5 wt .-% determined. The molecular weights M _{w of} the polymers were measured by light scattering.

Examples

Determination of edge penetration

The cardboard produced is laminated on both sides with an adhesive tape made of polyethylene. The thickness of the cardboard is then determined. Test strips of size 25 x 75 mm are then cut from the box and weighed in each case. In order to determine the edge penetration, the test strips are immersed in a bath containing a 30% hydrogen peroxide solution heated to 70 ° C. The test strips are removed from the bath after a dwell time of 10 minutes. Excess hydrogen peroxide is absorbed with filter paper. The test strips are weighed again. The edge penetration in kg / m ² is then calculated from the weight increase.

Ink flotation time

The Ink floating time (measured in minutes) is the time that a test ink according to DIN 53126 up to 50% breakthrough through a test sheet needed.

Cobb value

Determination was carried out in accordance with DIN 53 132 by storing the paper sheets in water for a period of 60 seconds. The water absorption is given in g / m ² .

Examples 1 to 6

To a paper stock with a consistency of 10 g / l made of 100% unbleached pine sulfate pulp with a freeness of 20 ° SR (Schopper-Riegler), 0.75% of a cationic starch (Solvitose BPN) was added as a retention agent, based on dry paper stock and adjusted the pH of the mixture to 7. The amounts of stearyldiketene given in the table were then metered in in the form of an aqueous dispersion (Basoplast ^® 4118MC) and an aqueous dispersion of the polymer sizes also mentioned in Table 1. The fiber slurries were mixed thoroughly and dewatered on a Rapid-Köthen sheet former. Sheets with a basis weight of 150 g / m ^{2 were obtained} .

The following polymer sizing agents were used:

Polymer sizing agent A: Basoplast ^® 250D (aqueous dispersion of a copolymer, prepared by emulsion polymerization of acrylonitrile and n-butyl acrylate in the presence of degraded cationic starch as emulsifier and hydrogen peroxide as initiator).

Polymer sizing agent B: Basoplast ^® 265D (aqueous dispersion of a copolymer, prepared by emulsion polymerization of styrene and n-butyl acrylate in the presence of degraded cationic starch as emulsifier and hydrogen peroxide as initiator).

Polymer sizing agent C: Basoplast ^® PR8172 (aqueous dispersion of a copolymer, prepared by emulsion polymerization of styrene and n-butyl acrylate in the presence of cationic starch as emulsifier and hydrogen peroxide as initiator). Table 1

The leaves were then dried on a steam-heated drying cylinder at a temperature of 90 ° C to a water content of 6-10%. After drying, the Cobb value of the leaves was determined. The sheets were then laminated on both sides with a film made of polyethylene with a density of 0.918 g / cm ³ (heating the composite under pressure to ° C.). The edge penetration of the three-layer composite was then determined. The results are shown in Table 3.

Comparative Examples 1 to 4

To a paper stock with a consistency of 10 g / l made of 100% unbleached pine sulfate pulp with a freeness of 20 ° SR (Schopper-Riegler), 0.75% of a cationic starch (Solvitose BPN) was added as a retention agent, based on dry paper stock and adjusted the pH of the mixture to 7. Then the amounts of stearyldiketene given in Table 2 were metered in the form of an aqueous dispersion (Basoplast ^® 4118MC). The aqueous fiber slurries were then mixed in each case and dewatered on a Rapid-Koethen sheet former to give a paper product with a basis weight of 150 g / m ² . Table 2

The leaves were then dried on a steam-heated drying cylinder at a temperature of 90 ° C to a water content of 6-10%. After drying, the Cobb value of the leaves was determined. The sheets were then glued on both sides with a film made of polyethylene (pressing the composite under pressure). The edge penetration of the three-layer composite against hydrogen peroxide was then determined. The results are shown in Table 3. Table 3

Claims (12)

Packaging material made of an at least two-layer composite of glued paper or glued cardboard and at least one water-impermeable film for the production of containers for the packaging of liquids, characterized in that the paper or the cardboard is glued in bulk with a polymer sizing agent. Packaging material according to claim 1, characterized in that the paper or cardboard in bulk with a polymer sizing agent is glued. Packaging material according to claim 1, characterized in that the paper or cardboard is in the surface is sized with a polymer sizing agent. Packaging material according to claim 1, characterized in that this Paper or cardboard in addition in the presence of aqueous Dispersions of reactive sizes and / or combinations of resin size and alum is glued. Packaging material according to claim 1 or 2, characterized characterized that the Paper or cardboard available is by successive addition of aqueous alkyl ketene dispersions and aqueous polymer sizing dispersions for Paper stock and drainage of the paper stock on the sieve of a paper machine. Packaging material according to one of claims 1 or 2, characterized in that the Paper or cardboard available is by simultaneous addition of aqueous alkyl ketene dimer dispersions and watery Polymer size dispersions for pulp and dewatering Paper stock on the sieve of a paper machine. Packaging material according to claim 1 or 2, characterized characterized that the Paper or cardboard available is by sizing with a mixture of sizing agents from an aqueous Polymer sizing agent dispersion and an aqueous alkyl ketene dimer dispersion. Packaging material according to one of claims 1 to 7, characterized in that the Paper or cardboard in addition is sized in the presence of cationic polymers. Packaging material according to one of claims 1 to 8, characterized in that the Paper or cardboard with a waterproof film on both sides is laminated from plastic and / or metal. Packaging material according to one of claims 1 to 9, characterized in that the paper or the cardboard is laminated on one or both sides with a film of polyethylene, polypropylene, copolymer of ethylene and propylene, polyester, polyvinyl alcohol, copolymer of ethylene and vinyl acetate, copolymer of ethylene and vinyl alcohol, polyamide and / or aluminum. Packaging material according to one of claims 1 to 8, characterized in that the paper or cardboard has a basis weight of 80 to 400 g / m ² and is laminated on both sides with a film made of polyethylene. Use of paper products that are available by (i) Bulk sizing of a paper stock from an aqueous slurry of cellulose fibers with at least one polymer sizing agent or with a polymer sizing agent and an aqueous dispersion of an alkyl ketene dimer or mixtures thereof in the presence of a retention aid and optionally a water soluble Aluminum compound and optionally at least one cationic polymers (ii) dewatering the paper stock on the sieve of a paper machine, (iii) drying of the paper product and (iv) single or double sided lamination the paper product with a plastic or metal foil, to Manufacture of containers for the Packaging of liquids, especially of beverages.