Two-component laminating adhesive

Abstract

A two-component laminating adhesive is described, wherein the first component of the laminating adhesive comprises dispersed particles of two polymers, the first polymer being producible by radical emulsion polymerization of specific ethylenically unsaturated free-radically polymerizable monomers, and the second polymer being a polyurethane; wherein the second component of the laminating adhesive comprises a crosslinking compound.

Description

manual

[0001] This invention relates to a two-component laminating adhesive, wherein one component of the laminating adhesive comprises dispersed particles of two polymers, the first polymer being capable of being produced by free radical emulsion polymerization of a monomer capable of free radical polymerization with a specific olefinic unsaturation, and the second polymer being polyurethane; wherein the second component of the laminating adhesive comprises a crosslinking compound. The invention also relates to a lamination method using said laminating adhesive and articles produced by said method.

[0002] Waterborne laminating adhesives are known to be based on aqueous dispersions of adhesive polyacrylates or aqueous dispersions of adhesive polyurethanes. These adhesives can be used to produce film-to-film or film-to-paper laminates. Laminating adhesives based on specific polyacrylates are described, for example, in WO 98 / 23656 A1 and WO 00 / 50480. Laminating adhesives based on specific low-urea polyurethanes are described, for example, in WO 2006 / 087317 A2. Polyurethane-based laminating adhesives are generally superior to and therefore preferred over polyacrylate-based laminating adhesives due to their superior adhesive properties, such as instantaneous peel strength at room temperature and peel strength at higher temperatures.

[0003] However, polyurethanes with good peel strength and sufficiently low glass transition temperatures are typically formed into relatively soft adhesive films on polymer carrier film substrates or carrier paper substrates. When the coated carrier is wound into rolls for storage, transport, and further use later, or when it is unwound for further processing of the rolls to produce flexible packaging, the soft polyurethane adhesive film can cause a roll-winding defect known as “stretching.”

[0004] Stretching is the effect of creating a convex / concave roll when a carrier web is wound into a roll, due to the sudden lateral movement of a portion of the roll and the slippage of the coated carrier layer. This roll winding defect has a classic concave or convex roll shape caused by the gradual misalignment of the roll edges. This is often encountered during the winding of film laminates used in the production of flexible packaging, or may only be noticed after the roll has begun to unwind. Defects in laminate rolls have serious consequences for further processing of the rolls used in the production of flexible packaging.

[0005] The aim is to provide a laminating adhesive that has the good adhesive properties of polyurethane-based laminating adhesives, particularly sufficiently high instantaneous peel strength at room temperature and sufficiently high peel strength at elevated temperatures (e.g., at about 65°C), while significantly minimizing or avoiding the risk of roll winding defects such as stretching of the produced laminate.

[0006] It has now been found that this problem can be solved by the two-component laminated adhesives that are claimed to be protected and described below.

[0007] This invention provides a two-component laminating adhesive, wherein one component of the laminating adhesive is in the form of an aqueous polymer dispersion comprising dispersed polymer particles of the following substances: (i) at least one first polymer, which can be produced by radical emulsion polymerization of an olefinically unsaturated, radically polymerizable monomer comprising... (a) Based on the total amount of monomers, at least 49% by weight, preferably 50% to 90% by weight, of at least one monomer selected from the group consisting of C2- to C12-alkyl acrylates and C2- to C12-alkyl methacrylates; (b) 5% to 50% by weight, preferably 9% to 40% by weight, of styrene based on the total amount of monomers; (c) Based on the total amount of monomers, 0.1% to 10% by weight, preferably 0.5% to 10% by weight, of at least one hydrophilic olefinic unsaturated monomer having at least one hydrophilic group selected from acid groups and hydroxyl groups, (d) Based on the total amount of monomers, 0% to 10% by weight of at least one other olefinic unsaturated monomer different from monomers a), b) and c), The glass transition temperature of the first polymer is greater than -30°C, preferably at least -25°C, more preferably -25°C to +5°C, and is measured by differential scanning calorimetry at a heating rate of 20°C / min. and (ii) at least one second polymer, the second polymer being an adhesive polymer selected from polyurethane; Furthermore, the second component of the laminating adhesive contains a crosslinking compound capable of crosslinking the first component.

[0008] The present invention also provides a lamination method in which two substrates are bonded together, wherein a) Provide a first substrate in the form of a first film or paper. b) Provide a second substrate, which is selected from paper or may be the same as or different from the first film. c) Provide a two-component adhesive according to the invention, and d) Apply the two-component adhesive to the first substrate and / or the second substrate, optionally allow it to dry, and laminate the first substrate onto the second substrate.

[0009] The present invention also provides a laminated product produced according to the method.

[0010] The present invention also provides the use of the two-component laminating adhesive as described herein for film-to-film lamination or for film-to-paper lamination.

[0011] The names “(meth)acrylic acid” or “(meth)acrylate” and similar names are occasionally used below as abbreviations for “acrylic acid or methacrylic acid” or “acrylate or methacrylate”. In the names Cx-(meth)acrylate alkyl ester and similar names, x indicates the number of carbon atoms in the alkyl group.

[0012] The glass transition temperature was determined by differential scanning calorimetry (ASTM D 3418-08, the so-called midpoint temperature). The glass transition temperature of the polymer in the polymer dispersion is the glass transition temperature evaluated during the second heating profile (heating rate 20 °C / min).

[0013] The molecular weight of a polymeric glycol is a number-average molecular weight, calculated from the OH value and measured according to DIN 53240.

[0014] The water-based laminating adhesive preferably comprises 30% to 60% by weight, particularly preferably 40% to 55% by weight, of the sum of a first polymer and a second polymer. The weight ratio of the first polymer to the second polymer is preferably 1:2 to 2:1, more preferably 1:1.5 to 1.5:1.

[0015] The aqueous laminating adhesive comprises at least one first adhesive polymer, which can be produced by free radical emulsion polymerization of an olefinically unsaturated monomer capable of free radical polymerization, hereinafter also referred to as an acrylic emulsion polymer. The emulsion polymer is dispersed in the laminating adhesive composition. The adhesive polymer has a glass transition temperature greater than -30°C, preferably at least -25°C, more preferably -25°C to +5°C, as measured by differential scanning calorimetry at a heating rate of 20°C / min. The glass transition temperature can be adjusted by using suitable monomers a) to d) known to those skilled in the art. Monomer (a)

[0016] The first polymer (acrylic emulsion polymer) is made from: (a) at least 49% by weight, preferably 50% to 90% by weight, of at least one monomer selected from the group consisting of C2- to C12-alkyl acrylates and C2- to C12-alkyl methacrylates, based on the total amount of monomers. Preferred monomers (a) are C2- to C8-alkyl acrylates, C2- to C8-alkyl methacrylates, and mixtures thereof. Preferred monomers (a) are one or more monomers selected from the group consisting of: ethyl acrylate, propyl acrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, tert-butyl (meth)acrylate, n-hexyl acrylate, cyclohexyl (meth)acrylate, 2-octyl acrylate, 2-ethylhexyl acrylate, and 2-propylheptyl acrylate. In particular, mixtures of alkyl (meth)acrylates are also suitable. Especially preferred are ethyl acrylate, n-butyl acrylate, n-butyl methacrylate, n-hexyl acrylate, 2-octyl acrylate, and 2-ethylhexyl acrylate. Monomer (b)

[0017] The first polymer (acrylic emulsion polymer) is made from: (b) styrene, 5% to 50% by weight, preferably 9% to 40% by weight, based on the total amount of monomers. Monomer (c)

[0018] The first polymer (acrylic emulsion polymer) is made from: (c) 0.1% to 10% by weight, preferably 0.5% to 10% by weight, of at least one hydrophilic olefinic unsaturated monomer having at least one hydrophilic group selected from acid groups and hydroxyl groups, based on the total amount of monomers. The monomer (c) having at least one acid group is preferably used in an amount of 0.5% to 6% by weight, based on the total amount of monomers. The monomer (c) having at least one hydroxyl group is preferably used in an amount of 1% to 10% by weight, based on the total amount of monomers.

[0019] Monomers (c) having acid groups include not only monomers containing at least one acid group, but also their anhydrides and salts. Monomers (c) include α,β-mono-ene unsaturated monocarboxylic acids and dicarboxylic acids, half-esters of α,β-mono-ene unsaturated dicarboxylic acids, anhydrides of the aforementioned α,β-mono-ene unsaturated carboxylic acids, and olefinic unsaturated sulfonic acids, phosphonic acids, or dihydrogen phosphate esters and their water-soluble salts (e.g., their alkali metal salts). Examples include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, vinylacetic acid, and vinyllactic acid. Suitable examples of olefinic unsaturated sulfonic acids include vinylsulfonic acid, styrenesulfonic acid, acryloylaminomethylpropanesulfonic acid, sulfopropyl acrylate, and sulfopropyl methacrylate. The monomer (c) having at least one acid group is preferably selected from the group consisting of acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, vinyl acetic acid, vinyl lactic acid, vinyl sulfonic acid, styrene sulfonic acid, acrylamidomethylpropanesulfonic acid, sulfopropyl acrylate, sulfopropyl methacrylate, and mixtures thereof. More preferably, the monomer (c) is an α,β-monoolefinically unsaturated C3-C8-carboxylic acid and a C4-C8-dicarboxylic acid, such as itaconic acid, crotonic acid, vinyl acetic acid, acrylamidoglycolic acid, acrylic acid, and methacrylic acid, and their anhydrides. Particularly preferred monomers (c) are itaconic acid, acrylic acid, methacrylic acid, and mixtures thereof.

[0020] The acid groups of monomer (c) may be present in an unneutralized form at the start of polymerization and may be completely or partially neutralized by a feed base during or after emulsion polymerization. For example, once at least 5% by weight, preferably 10% to 70% by weight, of the total monomer mixture is present in the reaction vessel under polymerization conditions, the feed base is initiated during emulsion polymerization (i.e., after the start of the polymerization reaction). The neutralizing agent may be added, for example, simultaneously with the feed of the monomer mixture in a separate feed. After all monomers have been fed, the polymerization vessel preferably contains the amount of neutralizing agent required to neutralize at least 10%, preferably 10% to 100%, or 25% to 90% of the acid equivalent. Suitable bases are, for example, sodium hydroxide solution, potassium hydroxide solution, ammonia (preferably in an aqueous solution), or organic amines, preferably tertiary amines, particularly trialkylamines having one to four carbon atoms in the alkyl group, such as, for example, triethylamine.

[0021] The monomer (c) having at least one hydroxyl group includes, for example, hydroxyalkyl esters of α,β-monoolefinic unsaturated carboxylic acids described above, preferably hydroxyalkyl (meth)acrylates having 1 to 10 carbon atoms in the alkyl group. Preferred monomers (c) having at least one hydroxyl group are selected from the group consisting of, for example, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, and mixtures thereof.

[0022] The monomers having an acid group (c) and the monomers having a hydroxyl group can be used in combination, for example, 0.5% to 6% by weight of one or more monomers having at least one acid group and 1% to 9.5% by weight of one or more monomers having at least one hydroxyl group, such as acrylic acid and / or methacrylic acid in combination with at least one monomer selected from the following: hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, 4-hydroxybutyl acrylate and 4-hydroxybutyl methacrylate. Monomer (d)

[0023] The first polymer (acrylic emulsion polymer) is made from: (d) 0% to 10% by weight of at least one additional olefinically unsaturated monomer different from monomers (a), (b), and (c), based on the total amount of monomers. Monomer (d) is preferably selected from the group consisting of: methyl acrylate, methyl methacrylate, vinyl esters of carboxylic acids containing up to 20 carbon atoms, vinyl aromatic compounds having up to 20 carbon atoms, vinyl halides, vinyl ethers of alcohols containing 1 to 10 carbon atoms, aliphatic hydrocarbons having 2 to 8 carbon atoms and one or two double bonds, acrylamide, methacrylamide, (meth)acrylic acid C1-C 10 Nitriles of aminoalkyl esters and α,β-mono-olefinically unsaturated C3-C8 carboxylic acids; bifunctional monomers having at least one group selected from glycidyl groups, oxazoline groups, urea groups, and urea-like groups in addition to an olefinically unsaturated double bond; and crosslinking monomers having more than one group capable of free radical polymerization, more particularly two or more (meth)acrylate groups, and mixtures of these monomers. Vinyl esters of carboxylic acids having 1 to 20 carbon atoms are, for example, vinyl laurate, vinyl stearate, vinyl propionate, vinyl tert-carbonate, and vinyl acetate. Vinyl aromatic compounds other than styrene include vinyltoluene, α-methylstyrene and p-methylstyrene, α-butylstyrene, 4-n-butylstyrene, and 4-n-decylstyrene. Vinyl halides are olefinically unsaturated compounds substituted with chlorine, fluorine, or bromine, preferably vinyl chloride and vinylidene chloride. Examples of vinyl ethers include, for example, vinyl methyl ether or vinyl isobutyl ether. Vinyl ethers of alcohols containing 1 to 4 carbon atoms are preferred. Hydrocarbons having 4 to 8 carbon atoms and two olefinic double bonds include butadiene, isoprene, and chloroprene. Preferred monomers having more than one group capable of free radical polymerization are butanediol di(meth)acrylate or allyl methacrylate.

[0024] Examples of oxazoline monomers are those groups in the following formula:

[0025] The functional groups are defined as follows:

[0026] R is a C that contains at least one olefinic unsaturated group. 2-20 -Alkenyl group;

[0027] R 3 R 4 R 5 and R 6 They are independently selected from H, halogens, and C. 1-20 -alkyl, C 2-20 -Alkenyl, C 6-20 -Aryl, C 7-32 -Arylalkyl, C 1-20 -hydroxyalkyl, C 1-20 -aminoalkyl and C 1-20 - Haloalkyl group, preferably selected from H, halogen and C 1-20 -alkyl. The oxazoline monomer is particularly preferably at least one monomer selected from the group consisting of: 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-vinyl-4-ethyl-2-oxazoline, 2-vinyl-4,4-dimethyl-2-oxazoline, 2-vinyl-5,5-dimethyl-2-oxazoline, 2-vinyl-4,4,5,5-tetramethyl-2-oxazoline. Phosphorus, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, 2-isopropenyl-4-ethyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, 2-isopropenyl-4,4-dimethyl-2-oxazoline, 2-isopropenyl-5,5-dimethyl-2-oxazoline, and 2-isopropenyl-4,4,5,5-tetramethyl-2-oxazoline. 2-vinyl-2-oxazoline and / or 2-isopropenyl-2-oxazoline are particularly preferred; 2-isopropenyl-2-oxazoline (iPOx) is particularly preferred.

[0028] Examples of monomers with a urea group or urea-like group are those groups, for example, those with the following formula:

[0029] Where X is CH2, O, NH or NR 1 And R 1 It is a C1-C4 alkyl group, R is hydrogen or methyl, and A is a divalent linking group, preferably a C1-C10 alkyl group or a C2-C4 alkyl group. Particularly preferred are urea alkyl esters of (meth)acrylate having 1 to 10 carbon atoms, preferably 2 to 4 carbon atoms in the alkyl group, especially urea ethyl methacrylate (UMA).

[0030] Particularly preferred monomers (d) are methyl acrylate, methyl methacrylate, and glycidyl methacrylate (an ester of methacrylic acid and glycidyl). Preferably, for example, is methyl methacrylate in an amount of 1% to 10% by weight based on the total amount of monomers. Also preferred, for example, is glycidyl methacrylate in an amount of 1% to 4% by weight based on the total amount of monomers.

[0031] The first polymer of the two-component laminated adhesive is preferably produced by free radical emulsion polymerization of an olefinically unsaturated, free radical polymerizable monomer comprising... (a) Based on the total amount of monomers, 50% to 90% by weight of at least one monomer selected from the group consisting of: ethyl acrylate, propyl acrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, tert-butyl (meth)acrylate, n-hexyl acrylate, cyclohexyl (meth)acrylate, 2-octyl acrylate, 2-ethylhexyl acrylate and 2-propylheptyl acrylate. (b) 9% to 40% styrene based on total monomer content; (c) Based on the total amount of monomers, 0.5% to 10% by weight of at least one hydrophilic olefinic unsaturated monomer having at least one hydrophilic group selected from acid groups and hydroxyl groups, wherein the hydrophilic monomer is selected from the group consisting of: acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, vinyl acetic acid, vinyl lactic acid, vinyl sulfonic acid, styrene sulfonic acid, acrylamidomethylpropanesulfonic acid, sulfopropyl acrylate, sulfopropyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate or hydroxypropyl methacrylate, 4-hydroxybutyl acrylate and 4-hydroxybutyl methacrylate; (d) Based on the total amount of monomers, 0% to 10% by weight of at least one other olefinic unsaturated monomer different from monomers a), b) and c).

[0032] In one embodiment, the first polymer of the two-component laminate adhesive can be produced by free radical emulsion polymerization of an olefinically unsaturated, free radical polymerizable monomer comprising... (a) Based on the total amount of monomers, 50% to 90% by weight of at least one monomer selected from the group consisting of: ethyl acrylate, propyl acrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, tert-butyl (meth)acrylate, n-hexyl acrylate, cyclohexyl (meth)acrylate, 2-octyl acrylate, 2-ethylhexyl acrylate and 2-propylheptyl acrylate. (b) 9% to 40% styrene based on total monomer content; (c) Based on the total amount of monomers, 0.5% to 6% by weight of at least one hydrophilic olefinic unsaturated monomer selected from the group consisting of acrylic acid and methacrylic acid; (d) Based on the total amount of monomers, 0% to 10% by weight of at least one other olefinic unsaturated monomer different from monomers a), b) and c).

[0033] In one embodiment, the first polymer of the two-component laminate adhesive can be produced by free radical emulsion polymerization of an olefinically unsaturated, free radical polymerizable monomer comprising... (a) Based on the total amount of monomers, 50% to 85% by weight of at least one monomer selected from the group consisting of: ethyl acrylate, propyl acrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, tert-butyl (meth)acrylate, n-hexyl acrylate, cyclohexyl (meth)acrylate, 2-octyl acrylate, 2-ethylhexyl acrylate and 2-propylheptyl acrylate. (b) 9% to 40% styrene based on total monomer content; (c) Based on the total amount of monomers, 2% to 6% by weight of at least one hydrophilic olefinic unsaturated monomer selected from the group consisting of: hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate or hydroxypropyl methacrylate, 4-hydroxybutyl acrylate and 4-hydroxybutyl methacrylate. (d) Based on the total amount of monomers, 0% to 10% by weight of at least one other olefinic unsaturated monomer different from monomers a), b) and c).

[0034] In one embodiment, the first polymer of the two-component laminate adhesive can be produced by free radical emulsion polymerization of an olefinically unsaturated, free radical polymerizable monomer comprising... (a) Based on the total amount of monomers, 55% to 85% by weight of at least one monomer selected from the group consisting of: ethyl acrylate, propyl acrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, tert-butyl (meth)acrylate, n-hexyl acrylate, cyclohexyl (meth)acrylate, 2-octyl acrylate, 2-ethylhexyl acrylate and 2-propylheptyl acrylate. (b) 9% to 40% styrene based on total monomer content; (c) Based on the total amount of monomers, 2% to 6% by weight of at least one hydrophilic olefinic unsaturated monomer selected from the group consisting of: hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate or hydroxypropyl methacrylate, 4-hydroxybutyl acrylate and 4-hydroxybutyl methacrylate. And does not contain other olefinic unsaturated monomers different from monomers a), b) and c).

[0035] In one embodiment, the first polymer of the two-component laminate adhesive can be produced by free radical emulsion polymerization of an olefinically unsaturated, free radical polymerizable monomer comprising... (a) Based on the total amount of monomers, 50% to 85% by weight of at least one monomer selected from the group consisting of: ethyl acrylate, propyl acrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, tert-butyl (meth)acrylate, n-hexyl acrylate, cyclohexyl (meth)acrylate, 2-octyl acrylate, 2-ethylhexyl acrylate and 2-propylheptyl acrylate. (b) 9% to 40% styrene based on total monomer content; (c) Based on the total amount of monomers, 2% to 6% by weight of at least one hydrophilic olefinic unsaturated monomer selected from the group consisting of: hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate or hydroxypropyl methacrylate, 4-hydroxybutyl acrylate and 4-hydroxybutyl methacrylate. (d) Glycidyl methacrylate, 1% to 4% by weight, based on the total amount of monomers.

[0036] The monomers used for polymerization of the first polymer are selected such that the measured glass transition temperature of the binder polymer is greater than -30°C, preferably at least -25°C, and more preferably -25°C to +5°C. By targeted variations in monomer type and amount, those skilled in the art can produce aqueous polymer compositions according to the invention, the polymers of which have glass transition temperatures within the desired range. Orientation can be performed using the Fox formula. According to Fox (TGFox, Bull. Am. Phys. Soc. 1956 [Ser. II] 1, p. 123, and according to Ullmann's Encyclopedia of Industrial Chemistry, Vol. 19, p. 18, 4th edition, Verlag Chemie, Weinheim, 1980), the glass transition temperature of the copolymer is given a good approximation by the following: 1 / T g = x 1 / T g 1 + x 2 / T g 2 + .... x n / T g n ,

[0037] Where x 1 x 2 , ...x n It is the mass fraction of monomers 1, 2, ... n, and T g 1 T g 2 , ...T g n It is the glass transition temperature in Kelvin for polymers composed of only one monomer from monomers 1, 2, ... n. The Tg of homopolymers of most monomers... g The values ​​are known and are listed, for example, in Ullmann's Encyclopedia of Industrial Chemistry, Vol. 5, A21, p. 169, VCH Weinheim, 1992; other sources of glass transition temperature for homopolymers are, for example, J. Brandrup, E. Himmergut, Polymer Handbook, 1st edition, J. Wiley, New York, 1966; 2nd edition, J. Wiley, New York, 1975; and 3rd edition, J. Wiley, New York, 1989.

[0038] In one embodiment of the invention, the free radical polymerization employs at least one chain transfer agent. This allows for a reduction in the molar mass and gel content of the emulsion polymer via a chain termination reaction. In this process, the chain transfer agent binds to the polymer, typically to the chain ends. The amount of chain transfer agent is particularly 0.05 to 4 parts by weight, especially preferably 0.05 to 0.8 parts by weight, and very particularly preferably 0.1 to 0.6 parts by weight, based on 100 parts by weight of the monomer to be polymerized. Suitable chain transfer agents are, for example, compounds having a thiol group, such as tert-butylthiol, ethyl methacrylate of mercaptoacetate, mercaptoethanol, mercaptopropyltrimethoxysilane, or tert-dodecyl mercaptoacetate. The chain transfer agent is typically a low molecular weight compound having a molecular weight of less than 2000 g / mol, particularly less than 1000 g / mol. Preferred are 2-ethylhexyl mercaptoacetate (EHTG), isooctyl 3-mercaptopropionate (IOMPA), and tert-dodecyl mercaptoacetate (tDMK).

[0039] Polymerization can be carried out under seed control, i.e., in the presence of a polymer seed (seed latex). The seed latex is an aqueous dispersion of polymer microparticles having an average particle size preferably from 20 nm to 40 nm. The seed latex is used preferably from 0.01 parts by weight to 0.5 parts by weight, particularly preferably from 0.03 parts by weight to 0.3 parts by weight, or from 0.03 parts by weight to no more than 0.1 parts by weight, based on 100 parts by weight of monomer. For example, latex based on polystyrene or polymethyl methacrylate is suitable. A preferred seed latex is a polystyrene seed.

[0040] Emulsion polymerization involves polymerizing olefinically unsaturated compounds (monomers) in water, typically using ionic and / or nonionic emulsifiers and / or protective colloids or stabilizers as surfactants to stabilize monomer droplets and subsequently polymer particles formed from the monomers. The surfactant is typically used in amounts of 0.1 to 10 parts by weight, preferably 0.2 to 5 parts by weight, based on 100 parts by weight of the monomer to be polymerized.

[0041] A detailed description of suitable protective colloids can be found in Houben-Weyl, Methoden der organischenChemie [Methods of Organic Chemistry], Vol. XIV / 1, Makromolekulare Stoffe [Macromolecular Materials], Georg-Thieme-Verlag, Stuttgart, 1961, pp. 411-420. Useful emulsifiers include anionic, cationic, and nonionic emulsifiers. As the surfactant, emulsifiers with a molecular weight typically lower than 2000 g / mol compared to the protective colloid are preferred. When using mixtures of surfactants, the components must, of course, be compatible with each other; in case of doubt, this can be checked based on several preliminary experiments. Anionic and nonionic emulsifiers are preferred as surfactants. Commonly used accompanying emulsifiers are, for example, ethoxylated fatty alcohols (EO degree: 3 to 50, alkyl groups: C8 to C5). 36 Ethoxylated monoalkylphenols, dialkylphenols, and trialkylphenols (EO degrees: 3 to 50, alkyl groups: C4 to C9), alkali metal salts of dialkyl esters of sulfosuccinic acid, and alkyl sulfates (alkyl groups: C8 to C9). 12 Alkali metal salts and ammonium salts, ethoxylated alkanols (EO degree: 4 to 30, alkyl group: C) 12 To C 18 Alkali metal salts and ammonium salts of alkylphenols (EO degree: 3 to 50, alkyl group: C4 to C9), alkali metal salts and ammonium salts of alkyl sulfonic acids (alkyl group: C4 to C9). 12To C 18 Alkali metal salts and ammonium salts, and alkylaryl sulfonic acids (alkyl groups: C9 to C10). 18 Alkali metal salts and ammonium salts.

[0042] Other suitable emulsifiers are compounds of the following general formula.

[0043] R5 and R6 are hydrogen or C4- to C14-alkyl groups and not both hydrogen, and X and Y can be alkali metal ions and / or ammonium ions. R5 and R6 are preferably straight-chain or branched alkyl groups having 6 to 18 carbon atoms (particularly having 6, 12, and 16 carbon atoms) or hydrogen, wherein R5 and R6 are not both hydrogen. X and Y are preferably sodium, potassium, or ammonium ions, with sodium ions being particularly preferred. Compounds in which X and Y are sodium, R5 is a branched alkyl group having 12 carbon atoms, and R6 is hydrogen or R5 are particularly advantageous. Industrial mixtures containing 50% to 90% by weight of the monoalkylated product are typically used. Commercially available suitable emulsifiers include, for example, Dowfax. ® 2 A1, Emulan ® NP 50, Dextrorot ® OC50, Emulgator 825, Emulgator 825 S, Emulan ® OG, Texapon ® NSO, Nekanil ® 904 S, Lumiten ® I-RA, Lumiten ® E 3065, Disponil ® FES 77, Lutensol ® AT 18, Steinapol VSL, and Emulphor NPS 25. The present invention preferably uses ionic emulsifiers or protective colloids. Ionic emulsifiers are particularly preferred, especially salts and acids, such as carboxylic acids, sulfonic acids, and sulfates, sulfonates, or carboxylates. Mixtures of ionic and nonionic emulsifiers can also be used particularly.

[0044] Emulsion polymerization can be initiated using water-soluble initiators. Examples of water-soluble initiators include ammonium and alkali metal salts of disulfuric acid peroxide (e.g., sodium disulfuric acid peroxide), hydrogen peroxide, or organic peroxides, such as tert-butyl hydroperoxide. So-called reduction-oxidation (redox) initiator systems are also suitable as initiators. Redox initiator systems typically consist of at least one inorganic reducing agent and an inorganic or organic oxidizing agent. The oxidizing component is, for example, an emulsion polymerization initiator previously listed above. The reducing component is, for example, an alkali metal salt of sulfurous acid, such as sodium sulfite, sodium bisulfite; an alkali metal salt of metabisulfite, such as sodium metabisulfite; bisulfite addition compounds of aliphatic aldehydes and ketones, such as acetone bisulfite; or a reducing agent, such as hydroxymethanesulfinic acid and its salts, or ascorbic acid. Redox initiator systems can be used with soluble metal compounds, the metal component of which can be present in multiple valence states. Typical redox initiator systems include, for example, ascorbic acid / ferrous(II) sulfate / sodium persulfate, tert-butyl hydroperoxide / sodium metabisulfite, and tert-butyl hydroperoxide / sodium hydroxymethanesulfinate. Individual components (e.g., reducing agent components) can also be mixtures, such as a mixture of sodium salt of hydroxymethanesulfinate and sodium metabisulfite.

[0045] The listed initiators are typically used in aqueous solution form, with the lower concentration limit determined by the acceptable amount of water in the dispersion and the upper concentration limit determined by the solubility of the specific compound in water. The initiator concentration, based on the monomer to be polymerized, is typically from 0.1% to 30% by weight, preferably from 0.3% to 20% by weight, and particularly preferably from 0.5% to 10% by weight. Two or more different initiators can also be used in emulsion polymerization.

[0046] Emulsion polymerization is preferably carried out at 30°C to 130°C, more preferably at 50°C to 90°C. The polymerization medium may consist of water alone, or a mixture of water and a miscible liquid such as methanol. Water alone is preferred. Emulsion polymerization can be carried out as a feed process, including staged or gradient process modes. During polymerization, polymer seeds may be added first to more effectively regulate particle size.

[0047] The method of adding initiators to the polymerization vessel during free radical aqueous emulsion polymerization is known to those skilled in the art. They can be added entirely to the polymerization vessel first, or used continuously or in stages at their consumption rate during the free radical aqueous emulsion polymerization. This depends specifically on the chemistry of the initiator system and the polymerization temperature. Preferably, a portion is added first, and the remainder is supplied to the polymerization zone at its consumption rate. To remove residual monomers, the initiator is typically added also after the emulsion polymerization is properly completed, i.e., after at least 95% monomer conversion. In feeding methods, the components can be added to the reactor from above, from the side, or from below through the bottom of the reactor.

[0048] Emulsion polymerization typically provides an aqueous polymer dispersion with a solids content of 15% to 75% by weight, preferably 40% to 60% by weight, and particularly preferably not less than 50% by weight.

[0049] The resulting polymer is preferably used in the form of an aqueous dispersion. The size distribution of the dispersion particles can be unimodal, bimodal, or multimodal, and is preferably unimodal. The average particle size of the polymer particles dispersed in the aqueous dispersion is preferably greater than 200 nm, more preferably greater than 250 nm, for example, 200 nm to 400 nm or 250 nm to 350 nm. (Average particle size x) PCS The particle size distribution was measured by photon correlation spectroscopy (ISO Standard 13321:1996). When the particle size distribution measurement contains only a single maximum value, the particle size distribution of the dispersion is unimodal.

[0050] The two-component laminated adhesive contains at least one second polymer in the first component, which is an adhesive polymer selected from polyurethane.

[0051] Suitable polyurethane dispersions are, in principle, obtained by reacting at least one polyisocyanate with at least one compound having at least two isocyanate reactive groups and dispersing it in water. Suitable polyurethanes also include so-called polyurethane-polyurea, which contains not only polyurethane groups but also urea groups. The polyurethane dispersion preferably contains at least one polyurethane comprising at least one polyisocyanate in copolymer form and at least one polymeric polyol. Specifically, the polyurethane may be formed from at least one polyisocyanate and at least one polymeric polyol. Suitable polymeric polyols are preferably selected from polyester diols, polyether diols, polycarbonate diols, and mixtures thereof. The polymeric polyols preferably have a number-average molecular weight of about 500 g / mol to 5000 g / mol. The molecular weight of the polymeric polyol can be determined by its OH value, which can be measured according to DIN 53 240. Polymeric diols are preferred. The polyurethane dispersion preferably comprises at least one polyurethane, which comprises at least one polyisocyanate and a diol component in copolymer form, wherein a) has a molecular weight of 500 g / mol to 5000 g / mol based on 10 mol% to 100 mol% of the total diol and b) has a molecular weight of 60 g / mol to 500 g / mol based on 0 mol% to 90 mol% of the total diol.

[0052] Based on the total weight of the monomers used to produce the polyurethane, the polyurethane is preferably constructed of at least 40% by weight of at least one diisocyanate and at least one polyether diol and / or polyester diol, particularly preferably at least 60% by weight, and very particularly preferably at least 80% by weight. Other suitable synthetic components reaching 100% by weight include, for example, polyisocyanates having at least three NCO groups and compounds different from polymeric polyols having at least two isocyanate reactive groups, as listed below. These include, for example, diols; diamines; polymers different from polymeric polyols having at least two active hydrogen atoms per molecule; compounds having two active hydrogen atoms per molecule and at least one ionizable / ionic group; and mixtures thereof.

[0053] The preferred polyurethane comprises the following components: a) At least one monomeric diisocyanate b) at least one diol, wherein b1) Based on the total amount of diol (b), 10 mol% to 100 mol% having a molecular weight of 500 g / mol to 5000 g / mol, and b2) Based on the total amount of diol (b), 0 mol% to 90 mol% has a molecular weight of 60 g / mol to 500 g / mol. c) At least one monomer different from monomers (a) and (b), having at least one isocyanate group or at least one isocyanate reactive group, the isocyanate reactive group also having at least one hydrophilic group or a potential hydrophilic group. d) Optionally, at least one other compound different from monomers (a) to (c) having at least two reactive groups selected from an alcohol hydroxyl group, a primary amino group, a secondary amino group, or an isocyanate group, and e) Optionally, at least one monofunctional compound having a reactive group different from monomers (a) to (d), wherein the reactive group is an alcohol hydroxyl group, a primary amino group, a secondary amino group, or an isocyanate group.

[0054] Particularly preferred is the ratio of diol b1) to diol b2) to be 0.1:1 to 5:1, and particularly preferred is 0.2:1 to 2:1. Diol b) is specifically selected from polytetrahydrofuran, polypropylene oxide, and polyester diol, which is selected from the reaction product of diol with dicarboxylic acid and lactone-based polydiol.

[0055] Compounds suitable as monomer (a) specifically include diisocyanate X(NCO)2, wherein X is an acyclic aliphatic hydrocarbon group having 4 to 15 carbon atoms, an alicyclic or aromatic hydrocarbon group having 6 to 15 carbon atoms, or an aryliphatic hydrocarbon group having 7 to 15 carbon atoms. Examples of such diisocyanates are tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethyl diisocyanate, 1,4-diisocyanate cyclohexane, 5-isocyanate cyclohexane-1-(isocyanate methyl)-1,3,3-trimethylcyclohexane (IPDI), 2,2-bis(4-isocyanate cyclohexyl)propane, trimethylhexane diisocyanate, 1,4-diisocyanate phenylene, and 2,4-diisocyanate. Isomers of cyclohexyl 2,6-diisocyanate, 4,4'-diisocyanate, 2,4'-diisocyanate, terephthalic diisocyanate, tetramethylbenzene dimethyl diisocyanate (TMXDI), bis(4-isocyanate cyclohexyl)methane (HMDI), such as trans / trans, cis / cis and cis / trans isomers, and mixtures thereof.

[0056] These diisocyanates are commercially available. Of particular importance are mixtures of toluene diisocyanate and diphenylmethane diisocyanate, each of which is a structural isomer; a mixture of 80 mol% of toluene 2,4-diisocyanate and 20 mol% of toluene 2,6-diisocyanate is particularly suitable and preferred. Furthermore, mixtures of aromatic isocyanates such as toluene 2,4-diisocyanate and / or toluene 2,6-diisocyanate with aliphatic or alicyclic isocyanates such as hexamethylene diisocyanate or IPDI are particularly advantageous, with a preferred ratio of aliphatic to aromatic isocyanate of 1:9 to 9:1, specifically 4:1 to 1:4.

[0057] The diol (b1) can be a polyester polyol, and they are known, for example, from Ullmann's Encyclopedia of Industrial Chemistry, 4th edition, Volume 19, pp. 62-65. Preferred is the use of a polyester polyol obtained by reacting a diol with a dicarboxylic acid. Instead of using a free polycarboxylic acid, the polyester polyol can also be produced using the corresponding polycarboxylic anhydride or a polycarboxylic ester of a corresponding lower alcohol, or a mixture thereof. The polycarboxylic acid can be aliphatic, alicyclic, aryliphatic, aromatic, or heterocyclic, and can optionally be substituted with, for example, a halogen atom, and / or can be unsaturated. Examples include: octanoic acid, azelaic acid, phthalic acid, isophthalic acid, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrachlorophthalic anhydride, inner methylene tetrahydrophthalic anhydride, glutaric anhydride, maleic acid, maleic anhydride, fumaric acid, and dimer fatty acids. The preferred formulation is HOOC-(CH2). y Dicarboxylic acids of the -COOH group, where y is a number from 1 to 20, preferably an even number from 2 to 20, such as succinic acid, adipic acid, sebacic acid, and dodecanedicarboxylic acid. Suitable diols include, for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,4-butynediol, 1,5-pentanediol, neopentanediol, dimethylolcyclohexane such as 1,4-dimethylolcyclohexane, 2-methylpropane-1,3-diol, methylpentanediol, as well as diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, dibutylene glycol, and polybutanediol. Preferred alcohols are those of the general formula HO-(CH2). x Those with -OH groups, where x is a number from 1 to 20, preferably an even number from 2 to 20. Examples are ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, and 1,12-dodecanediol. Neopentyl glycol is also preferred.

[0058] Diol (b1) can also be a polycarbonate diol, such as those that can be obtained by reacting phosgene with an excess of low molecular weight alcohols listed as synthetic components of polyester polyols.

[0059] The diol (b1) can also be a lactone-based polyester diol, particularly a homopolymer or copolymer of lactone, preferably an addition product of the lactone to a suitable bifunctional initiator molecule containing a terminal hydroxyl group. The lactones considered preferably include those derived from the general formula HO-(CH2). zCompounds containing -COOH, where z is a number from 1 to 20, and one hydrogen atom of the methylene unit may be substituted with a C1- to C4-alkyl group. Examples include ε-caprolactone, β-propiolactone, γ-butyrolactone, and / or methyl-γ-caprolactone, and mixtures thereof. Suitable initiator components are, for example, low molecular weight diols as synthetic components of polyester polyols as described above. Polymers corresponding to ε-caprolactone are particularly preferred. Lower polyester glycols or polyether glycols may also be used as initiators for the production of lactone polymers. Instead of lactones, corresponding chemically equivalent condensation polymers of the hydroxycarboxylic acids corresponding to lactones may also be used.

[0060] The diol (b1) can also be a polyether diol. Specifically, polyether diols can be obtained by homopolymerization of ethylene oxide, propylene oxide, butane oxide, tetrahydrofuran, styrene oxide, or epichlorohydrin, for example in the presence of BF3, or by optionally adding these compounds, either in mixture form or sequentially, to an initiator component having reactive hydrogen atoms, such as an alcohol or amine, for example water, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2,2-bis(4-hydroxyphenyl)propane, or aniline. Polyether diols with a molecular weight of 500 to 5000, specifically 600 to 4500, are particularly preferred. Particularly preferred polyether diols are polypropylene oxide and polytetrahydrofuran. Suitable polytetrahydrofuran can be produced by cationic polymerization of tetrahydrofuran in the presence of an acidic catalyst such as, for example, sulfuric acid or fluorosulfuric acid. Such production methods are known to those skilled in the art. Suitable compound b1) also includes α,ω-diamino polyethers that can be produced by amination of alkylene oxides with ammonia.

[0061] b1) A polyether glycol containing only less than 20% by weight of ethylene oxide based on its total weight. A polyether glycol containing at least 20% by weight of the introduced ethylene oxide unit is a hydrophilic polyether glycol included in monomer c).

[0062] Optionally, polyhydroxyolefins, preferably those having two terminal hydroxyl groups, can also be used as monomers (b1), such as α-ω-dihydroxy polybutadiene, α-ω-dihydroxy polymethacrylate, or α-ω-dihydroxy polyacrylate. Such compounds are disclosed, for example, in EP-A 622 378. Other suitable polyols are polyacetals, polysiloxanes, and alkyd resins.

[0063] Preferably, at least 95 mol% of the diol (b1) is a polyether diol, particularly polypropylene glycol.

[0064] When not only diol b1) but also a low molecular weight diol b2 with a molecular weight of about 60 g / ml to 500 g / ml, preferably 62 g / ml to 200 g / ml, is used as diol (b), the hardness and elastic modulus of the polyurethane can be improved. The monomer b2) used particularly includes synthetic components of short-chain alkanediols used in the production of polyester polyols, wherein unbranched diols having 2 to 12 carbon atoms and an even number of carbon atoms, as well as 1,5-pentanediol and neopentanediol, are preferred. The diols considered (b2) include, for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,4-butynediol, 1,5-pentanediol, neopentanediol, dimethylolcyclohexane such as 1,4-dimethylolcyclohexane, 2-methylpropane-1,3-diol, methylpentanediol, as well as diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, dibutylene glycol, and polybutanediol. Preferred alcohols are those with the general formula HO-(CH2). x Those with -OH groups, where x is a number from 1 to 20, preferably an even number from 2 to 20. Examples are ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, and 1,12-dodecanediol. Neopentyl glycol is also preferred.

[0065] To ensure that the polyurethane is water-dispersible, the polyurethane comprises a monomer (c) as a synthetic component, which is different from components (a) and (b) and has at least one isocyanate group or at least one isocyanate reactive group, and also has at least one hydrophilic group or a group that can be converted into a hydrophilic group. Hereinafter, the term "hydrophilic group or potentially hydrophilic group" is abbreviated as "(potential) hydrophilic group". The reaction of the (potential) hydrophilic group with the isocyanate is substantially slower than that of the functional groups of the monomers used to construct the polymer backbone. The proportion of the component containing the (potential) hydrophilic group in the total amount of components (a) to (f) is generally measured such that the molar amount of the (potential) hydrophilic group (preferably anionic or potentially anionic group) is from 30 mmol / kg to 1000 mmol / kg, preferably from 50 mmol / kg to 500 mmol / kg, and particularly preferably from 80 mmol / kg to 300 mmol / kg, based on the weight of all monomers (a) to (e). The (potential) hydrophilic group can be nonionic or preferably (potential) ionic hydrophilic.

[0066] The nonionic hydrophilic groups considered specifically include polyethylene glycol ethers composed of preferably 5 to 100, preferably 10 to 80 ethylene oxide repeating units. The content of the ethylene oxide units is typically 0% to 10% by weight, preferably 0% to 6% by weight, based on the weight of all monomers (a) to (e). Preferred monomers containing nonionic hydrophilic groups are polyethylene oxide glycols, polyethylene oxide monools, and reaction products of polyethylene glycol with diisocyanates having terminal etherified polyethylene glycol groups, containing at least 20% by weight of ethylene oxide. Such diisocyanates and methods for their production are described in patent documents US-A 3,905,929 and US-A 3,920,598.

[0067] Ionic hydrophilic groups, especially anionic groups, such as sulfonate groups, carboxylate groups, and phosphate groups in the form of their alkali metal salts or ammonium salts, and cationic groups, such as ammonium groups, specifically protonated tertiary amino groups or quaternary ammonium groups. Potential ionic hydrophilic groups, especially those that can be converted into the aforementioned ionic hydrophilic groups by simple neutralization, hydrolysis, or quaternization reactions, i.e., carboxylate groups or tertiary amino groups. (Potential) ionic monomers (c) are described in detail, for example, in Ullmann's Encyclopedia of Industrial Chemistry, 4th edition, Volume 19, pp. 311-313, and, for example, in DE-A 1 495 745.

[0068] (Potential) cationic monomers (c) of particular practical importance are monomers containing tertiary amino groups, such as: tri(hydroxyalkyl)amines, N,N'-bis(hydroxyalkyl)alkylamines, N-hydroxyalkyldialkylamines, tri(aminoalkyl)amines, N,N'-bis(aminoalkyl)alkylamines, and N-aminoalkyldialkylamines, wherein the alkyl groups and alkyldiyl units of these tertiary amines are independently composed of 1 to 6 carbon atoms. Polyethers containing a tertiary nitrogen atom and preferably two terminal hydroxyl groups are also considered, for example, those obtainable in a manner conventional to themselves, such as by alkoxylation of an amine containing two hydrogen atoms attached to the amine nitrogen, for example, methylamine, aniline, or N,N,N'-dimethylhydrazine. Such polyethers typically have molecular weights between 500 g / mol and 6000 g / mol. These tertiary amines are converted into ammonium salts by means of an acid, preferably a strong inorganic acid such as phosphoric acid, sulfuric acid, hydrohalic acid or a strong organic acid, or by conversion with a suitable quaternizing agent such as a C1- to C6-alkyl halide or benzyl halide, for example a bromide or chloride.

[0069] The monomers considered to contain (potential) anionic groups generally include aliphatic, alicyclic, aryliphatic, or aromatic carboxylic acids and sulfonic acids having at least one hydroxyl group or at least one primary or secondary amino group. Preferred are dihydroxyalkyl carboxylic acids, specifically containing 3 to 10 carbon atoms, as described in US 3,412,054. Preferred compounds specifically include compounds of general formula (c1).

[0070] Where R 1 and R 2 Represents C1- to C4-alkyldiyl (units), and R 3 The term refers to C1- to C4-alkyl (units), specifically dimethylolpropionic acid (DMPA). Corresponding dihydroxysulfonic acids and dihydroxyphosphonic acids, such as 2,3-dihydroxypropanephosphonic acid, are also suitable. Dihydroxy compounds with a molecular weight greater than 500 g / mol to 10000 g / mol and containing at least two carboxylate groups are also suitable, as disclosed in DE-A 39 11 827. These can be obtained by reacting the dihydroxy compound with a tetracarboxylic dianhydride, such as pyromellitic dianhydride or cyclopentanetetracarboxylic dianhydride, in a molar ratio of 2:1 to 1.05:1 in an addition polymerization reaction. Suitable dihydroxy compounds are specifically monomers (b2) and diols (b1) listed as chain extenders.

[0071] The monomers (c) considered to contain isocyanate reactive amino groups also include aminocarboxylic acids such as lysine, β-alanine, or adducts of aliphatic diprimary diamines mentioned in DE-A 20 34 479 onto α,β-unsaturated carboxylic acids or sulfonic acids. Such compounds, for example, conform to formula (c2). H2N-R 4 -NH-R 5 -X(c2)

[0072] Where R 4 and R 5 Each of the C1- to C6-alkyldiyl units represents an independent unit, preferably an ethylene; and X represents COOH or SO3H. Particularly preferred compounds of formula (c2) are N-(2-aminoethyl)-2-aminoethanecarboxylic acid and N-(2-aminoethyl)-2-aminoethanesulfonic acid and their corresponding alkali metal salts, wherein sodium is a particularly preferred counterion. Also particularly preferred are the adducts of the above-described aliphatic diprimary diamines onto 2-acrylamido-2-methylpropanesulfonic acid, as described, for example, in DE–B 1 954 090.

[0073] When using monomers containing potentially ionic groups, the conversion of the monomer to its ionic form can occur before, during, but preferably after the isocyanate polymerization, because ionic monomers generally have poor solubility in the reaction mixture. Neutralizing agents are, for example, ammonia, NaOH, triethanolamine (TEA), triisopropylamine (TIPA), or morpholine and its derivatives. Sulfonate or carboxylate groups are particularly preferred in the form of salts with alkali metal ions or with ammonium ions as counterions.

[0074] Monomers (d), which differ from monomers (a) to (c) and are optionally also components of polyurethane, are typically used for crosslinking or chain extension. They are generally more common than di-nonphenolic alcohols, amines containing two or more primary and / or secondary amino groups, and compounds containing one or more primary and / or secondary amino groups in addition to one or more alcohol hydroxyl groups. Alcohols with a hydration degree greater than 2 and which can be used to establish a certain degree of branching or crosslinking are, for example, trimethylolpropane, glycerol, and sugars.

[0075] Monohydric alcohols containing not only hydroxyl groups but also other isocyanate-reactive groups, such as monoethanolamines with one or more primary and / or secondary amino groups, are also considered. When chain extension and / or crosslinking are carried out in the presence of water, polyamines with two or more primary and / or secondary amino groups are primarily used because amines generally react with isocyanates faster than alcohols or water. This is often necessary when crosslinked polyurethanes or aqueous dispersions of high molecular weight polyurethanes are required. In such cases, the process involves producing a prepolymer containing isocyanate groups, rapidly dispersing the prepolymer in water, and subsequently chain-extending or crosslinking the prepolymer by adding a compound containing multiple isocyanate-reactive amino groups.

[0076] Suitable amines for this purpose are typically polyfunctional amines with a molecular weight of 32 g / mol to 500 g / mol, preferably 60 g / mol to 300 g / mol, comprising at least two amino groups selected from primary and secondary amino groups. Examples are diamines such as diaminoethane, diaminopropane, diaminobutane, diaminohexane, piperazine, 2,5-dimethylpiperazine, amino-3-aminomethyl-3,5,5-trimethylcyclohexane (isophorone diamine, IPDA), 4,4'-diaminodicyclohexylmethane, 1,4-diaminocyclohexane, aminoethylethanolamine, hydrazine, hydrazine hydrate, or triamines such as diethylenetriamine or 1,8-diamino-4-aminomethyloctane. Amines can also be used in capped forms, such as corresponding ketimines (see, for example, CA-A 1 129 128), ketazines (see, for example, US-A 4,269,748), or amine salts (see US-A 4,292,226). For example, oxazolidinone used in US-A 4,192,937 also represents a capped polyamine, which can be used to produce polyurethanes according to the invention for chain extension of prepolymers. The use of such capped polyamines typically involves mixing the polyamine with the prepolymer in the absence of water, followed by mixing the mixture with a dispersing water or a portion of the dispersing water, thereby releasing the corresponding polyamine via hydrolysis. A mixture of diamines and triamines is preferably used, particularly preferably a mixture of isophorone diamine (IPDA) and diethylenetriamine (DETA).

[0077] Based on the total amount of components (b) and (d), the polyurethane preferably contains 1 mol% to 30 mol%, and particularly preferably 4 mol% to 25 mol% of a polyamine containing at least two isocyanate-reactive amino groups as monomer (d). For the same purpose, isocyanates with higher than bifunctionality may also be used as monomer (d). Commercially available compounds include, for example, isocyanurates of hexamethylene diisocyanate or biuret.

[0078] The monomers (e) optionally used together are monoisocyanates, monohydric alcohols, and monoprimary and secondary amines. Their proportion, based on the total molar amount of monomers, typically does not exceed 10 mol%. These monofunctional compounds typically contain additional functional groups such as olefinic or carbonyl groups and are used to introduce functional groups into polyurethanes, enabling the dispersion or crosslinking of the polyurethane or reactions with other similar polymers. Therefore, monomers such as isopropenyl-a,a'-dimethylbenzyl isocyanate (TMI) and esters of acrylic acid or methacrylic acid such as hydroxyethyl acrylate or hydroxyethyl methacrylate are considered.

[0079] Preferred is polyurethane, wherein the diisocyanate a) is selected from diisocyanates of formula X(NCO)2, wherein X represents an acyclic aliphatic hydrocarbon group having 4 to 15 carbon atoms, an alicyclic hydrocarbon group having 6 to 15 carbon atoms, an aromatic hydrocarbon group having 6 to 15 carbon atoms, or an aryliphatic hydrocarbon group having 7 to 15 carbon atoms, preferably selected from the group consisting of hexamethylene diisocyanate, 5-isocyano-1-(isocyanomethyl)-1,3,3-trimethylcyclohexane, 2,6-diisocyanotoluene, 2,4-diisocyanotoluene, and tetramethylphenyl dimethyl diisocyanate or mixtures thereof; the diol b1) is selected from polyester diol, polycarbonate diol, and polyether diol; and the compound c) is selected from dihydroxycarboxylic acid, diaminocarboxylic acid, and diaminosulfonic acid.

[0080] The ability to adjust the molecular weight of polyurethane by selecting the ratio of mutually reactive monomers and the arithmetic mean of the number of reactive functional groups per molecule is common knowledge in the field of polyurethane chemistry. Components (a) to (e) and their respective molar amounts are typically chosen such that the ratio A:B is 0.5:1 to 2:1, preferably 0.8:1 to 1.5:1, and particularly preferably 0.9:1 to 1.2:1, wherein... A is the molar amount of isocyanate groups, and B is the sum of the molar amount of hydroxyl groups and the molar amount of functional groups that can react with isocyanates in addition reactions. A ratio of A:B that is very close to 1:1 is a particularly preferred option.

[0081] The monomers (a) to (e) used typically have an average of 1.5 to 2.5, preferably 1.9 to 2.1, particularly preferably 2.0 isocyanate groups or functional groups that can react with isocyanates in addition reactions.

[0082] Polyurethane is preferably characterized by being amorphous and non-crystalline. Polyurethane preferably has a K value between 20 and 80. The K value is a relative viscosity value similar to that measured at 25°C in DIN 53 726. It includes the flow rate of a 1% by weight concentration solution of polyurethane in DMF relative to the flow rate of pure DMF, and characterizes the average molecular weight of the polyurethane.

[0083] The polyurethane preferably has a glass transition temperature of -60°C to -10°C, measured by differential scanning calorimetry at a heating rate of 20°C / min.

[0084] The addition polymerization of components (a)-(e) in the production of polyurethane is preferably carried out at a reaction temperature of up to 180°C, preferably up to 150°C, under standard or autogenous pressure. The production of polyurethane and aqueous polyurethane dispersions is known to those skilled in the art.

[0085] In the context of this invention, an aqueous polyurethane dispersion should be understood to mean a dispersion having an aqueous solvent as the continuous phase. Suitable aqueous solvents are mixtures of water and water-miscible solvents, such as alcohols, including methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, n-hexanol, and cyclohexanol; diols, such as ethylene glycol, propylene glycol, and butanediol; methyl or ethyl ethers of diols, diethylene glycol, triethylene glycol, polyethylene glycol having a number average molecular weight of up to about 3000, glycerol, and dioxane; and ketones, such as acetone. In one specific embodiment, the polyurethane dispersion is substantially free of organic solvents. "Substantially free of organic solvents" should be understood to mean that the proportion of organic solvents, based on the total weight of the solvents, does not exceed 5% by weight, particularly preferably not more than 1% by weight, and specifically not more than 0.1% by weight.

[0086] In a preferred embodiment, the production of polyurethane is carried out in the presence of at least one organic solvent. Preferred organic solvents for producing polyurethane are ketones, such as acetone and methyl ethyl ketone, as well as N-methylpyrrolidone. Acetone is particularly preferred. If a solvent at least partially miscible with water is used to produce the polyurethane, the polyurethane dispersion according to the invention may contain not only water but also the organic solvent used in its production. It should be understood that the production of the polyurethane dispersion according to the invention can be carried out in the presence of at least one organic solvent, which is subsequently partially or completely replaced by water.

[0087] The pH of the components of the laminating adhesive in the form of an aqueous polymer dispersion is preferably adjusted to a pH greater than 5, particularly to a pH between 5.5 and 8.

[0088] Aqueous polymer dispersions can be used as is or formulated with conventional additional auxiliaries (additives). Typical auxiliaries include, for example, defoamers, preservatives, UV stabilizers, catalysts, desiccants, antistatic agents, flame retardants, thickeners (preferably associative thickeners), thixotropic agents, surfactants, viscosity modifiers, plasticizers, leveling agents, tackifiers, wetting agents, or chelating agents. For better surface wetting, the polymer dispersion may particularly include wetting agents such as fatty alcohol ethoxylates, alkylphenol ethoxylates, nonylphenol ethoxylates, or sodium dodecyl sulfonate. Based on the total weight of the aqueous polymer dispersion, the amount of additional auxiliaries is preferably from 0.05% to 5% by weight, particularly from 0.25% to 3% by weight.

[0089] The first component of the two-component laminated adhesive is an aqueous composition, which preferably contains... (i) 25% to 70% by weight of at least one first polymer; (ii) 25% to 70% by weight of at least one second polymer; (iii) 0.25% to 5% by weight of one or more additives, preferably selected from the group consisting of: defoamers, preservatives, UV stabilizers, catalysts, desiccants, antistatic agents, flame retardants, thickeners, thixotropic agents, surfactants, viscosity modifiers, plasticizers, leveling agents, tackifiers, wetting agents or chelating agents.

[0090] For sustainability reasons, bio-based materials are preferably used to produce at least one first polymer and / or at least one second polymer. The term "bio-based" means that the material is biologically derived and comes from biomaterials / renewable resources. Renewably derived materials or biomaterials are organic materials in which carbon originates from CO2 recently (on a human timescale) fixed from the atmosphere through photosynthesis. Biomaterials (100% naturally derived carbon) have a carbon content greater than 10... -12 Typically about 1.2 × 10 −12 of 14 C / 12 The carbon isotope ratio is significant, while fossil materials have a ratio of 0. In reality, isotopes... 14 Carbon is formed in the atmosphere and subsequently integrated through photosynthesis, a process that takes at most a few decades. 14 The half-life of carbon is 5,730 years. Therefore, materials derived from photosynthesis, typically plants, must have the highest content of this isotope. 14 C. The determination of the biomaterial or biocarbon content can be performed according to standard ASTM D 6866-12, method B (ASTM D 6866-06), and ASTM D7026 (ASTM D 7026-04). The polymer of the first component of the two-component laminating adhesive preferably consists of a bio-based material comprising at least 5% by weight, more preferably at least 10% by weight, of the total amount of all polymers based on the first and second polymers.

[0091] Suitable bio-based materials for producing the first polymer via emulsion polymerization are, for example, (meth)acrylates, wherein the (meth)acrylate component or the alcohol component, or both, is bio-based. Various methods for producing bio-based acrylic acid from renewable plant materials are mentioned in EP 2626397 A1. Suitable bio-based alcohols are, for example, bio-based isobutanol, bio-based n-butanol, bio-based ethanol, bio-based isoamyl alcohol (3-methylbut-1-ol), bio-based 2-octanol, bio-based 1-octanol, and bio-based n-heptol. Preferred partially bio-based monomers are esters of (meth)acrylate and bio-based alcohols, preferably bio-based 2-octanol, bio-based 1-octanol, bio-based ethanol, bio-based isobutanol, bio-based n-butanol, bio-based isoamyl alcohol (3-methylbut-1-ol), and bio-based and bio-based n-heptol. Preferred fully bio-based monomers are esters of bio-based acrylic acid and bio-based alcohols as mentioned above. Preferably, at least one carbon atom of the alkyl group of at least one of the monomers 2-octyl acrylate, 1-octyl acrylate, isobutyl acrylate, and ethyl acrylate is of biological origin. Preferably, at least 50% by weight, more preferably 100% by weight, of the 2-octyl acrylate monomer is made from bio-based 2-octanol and non-bio-based acrylic acid or bio-based acrylic acid, i.e., preferably, at least one carbon atom of the 2-octyl group of the 2-octyl acrylate is of biological origin. Preferably, the monomer comprises isobutyl acrylate, wherein at least one carbon atom of the isobutyl group is of biological origin.

[0092] Suitable bio-based materials for the production of polyurethane are, for example, alcohols (specifically diols and polyols) and organic acids (specifically diacids) derived from natural materials such as starch, sucrose, glucose, lignocellulose, natural rubber, or vegetable oils. Suitable alcohols and organic acids derived from natural materials are, for example, ethanol, monoethylene glycol, polyethylene glycol, isosorbide, 1,3-propanediol, 1,4-butanediol, glycerol, adipic acid, or succinic acid. Preferably, at least a portion of the polyurethane is made from bio-based materials.

[0093] For sustainability reasons, it is preferred to use recycled raw materials to produce at least one first polymer and / or at least one second polymer. Polyurethane is found in many products, such as flexible foams (paper foam, sponge, upholstered furniture), rigid foams (insulation materials, building materials), thermoplastics (sports shoes), coatings (varnishes, paints), or adhesives. Sustainable recycling of polyurethane waste is required, which allows the reuse of the building blocks of polyurethane polymers. To this end, the bonds in the polyurethane are broken to obtain defined degradation products, and thus make them recyclable and reusable in the production of new polyurethane. Polyurethane adhesives preferably consist of at least 5% by weight, more preferably at least 10% by weight, of recycled material based on the sum of all polyurethane adhesive synthetic components. One method for recycling polyurethane is thermal recovery. This process is carried out at high temperatures and uses catalysts to recover monomers or building blocks. For example, thermal glycolysis (which is currently the most common chemical decomposition method used for polyurethane recovery) has been implemented industrially. Thermal glycolysis allows for the recovery of polyols. DE 102004014165 describes a method for producing polyols from waste polyurethane by reacting a mixture of waste polyurethane, glycols, or low-polyester mixtures (from polyester production) with aliphatic primary and / or aliphatic secondary amines. EP 0733669A2 describes a method for utilizing plastic waste containing a mixture of polyurethane and other plastics, comprising (a) reacting the waste with a mixture of low molecular weight at least bifunctional alcohols (I) and polyether polyols (II), and (b) separating the polyol glycolysis products from the remaining waste by mechanical means. The glycolytic polyols obtained by this process can be used to manufacture new polyurethane. The low-amine glycolysis products from polyurethane waste are preferably used as recycled polyols. For economic reasons, new polyurethane is produced using preferably at least 5% by weight, more preferably at least 10% by weight, of the recycled polyol, based on the total amount of isocyanate reactive compounds.

[0094] Recyclable polyols can be obtained by glycolysis of polyurethane waste using short-chain hydroxyl-containing compounds (such as, for example, ethylene oxide-propylene oxide copolymers, OH-functionalized polybutadiene), ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, oligomeric polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, oligomeric propylene glycol, ethylene oxide-propylene oxide copolymers, butanediol, OH-functionalized polybutadiene, neopentyl glycol, glycerol, diethanolamine, and triethanolamine, optionally obtained at higher temperatures in the presence of an organometallic catalyst. Non-enzymatic hydrolysis under high temperature and pressure allows the recovery of polyols and amines as reusable products.

[0095] Another approach is to enzymatically degrade polyurethane into defined monomers, which can be reused, for example, by carbamate enzymes as described in WO2019 / 243293, to produce new polyurethane. The recycled feedstock from the enzymatic degradation used to produce new polyurethane is preferably a low molecular weight degradation product, preferably a low molecular weight degradation product of polyester-based polyurethane, preferably having a molecular weight of up to 1,000 g / mol.

[0096] Suitable recycled raw materials are, for example, (i) a polyol and a polycarboxylic acid used to synthesize a polyester polyol, which is then used to synthesize the polyurethane under discussion; and (ii) An amine derived from the isocyanate used in the production of the polyurethane discussed, such as 2,4-toluenediamine in the case of 2,4-toluenedicyanate.

[0097] "Polyols" should be understood to mean any compound having at least two hydroxyl groups.

[0098] The low molecular weight polyol preferably has a molecular weight of up to 300 g / mol. Preferred recycled low molecular weight polyols are selected from the group consisting of: ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,2-dipropylene glycol, neopentyl glycol, glycerol, 1,1,1-trimethylolpropane, sucrose, sorbitol, and pentaerythritol.

[0099] "Polycarboxylic acid" should be understood to mean any compound containing at least two carboxyl groups. The low molecular weight polycarboxylic acid preferably has a molecular weight of up to 300 g / mol. Preferred recycled low molecular weight polycarboxylic acids are selected from the group consisting of: succinic acid, glutaric acid, adipic acid, phthalic acid, terephthalic acid, triphenylcarboxylic acid, oleic acid, and ricinoleic acid.

[0100] "Polyamine" should be understood to mean any compound containing at least two amino groups. The low molecular weight polyamine preferably has a molecular weight of up to 300 g / mol. Preferred low molecular weight recycled polyamines are selected from the group consisting of: 4,4'-methylenediamine, 2,4'-methylenediamine, 2,2'-methylenediamine, 2,4-toluenediamine, 2,6-toluenediamine, hexamethylenediamine, isophoronediamine, phenylenediamine, pentamethylmethylenediamine, p-phenylenediamine, butanediamine, and H12-methylenediamine. Polyamines are particularly preferably selected from the group consisting of: 4,4'-methylenediamine, 2,4'-methylenediamine, 2,2'-methylenediamine, 2,4-toluenediamine, and 2,6-toluenediamine.

[0101] In one aspect of the invention, the two-component laminated adhesive comprises a first polymer, a second polymer, or both made at least in part from a bio-based or recycled material.

[0102] The second component of the laminating adhesive contains a crosslinking compound capable of crosslinking the first component (i.e., at least one of the first polymer and the second polymer that crosslinks the first component).

[0103] The weight ratio of the crosslinking compound to the first and second polymers, based on 100 parts by weight of polymers, is preferably 1 to 5 parts by weight.

[0104] The crosslinking compound of the second component of the laminating adhesive is preferably at least one compound selected from the group consisting of polyisocyanates and polycarbodiimides.

[0105] Suitable crosslinking compounds are at least one, for example one to three, preferably one to two, and more preferably exactly one polyisocyanate, which can be obtained by reacting at least one monomeric isocyanate. The monomeric isocyanate used to obtain the polyisocyanate can be aromatic, aliphatic, or alicyclic, preferably aliphatic or alicyclic, referred to herein simply as (cyclic)aliphatic; aliphatic isocyanates are particularly preferred. Aromatic isocyanates are those isocyanates containing at least one aromatic ring system, i.e., both pure aromatic and aryliphatic compounds. Cyclic aliphatic isocyanates are those isocyanates containing at least one cyclic aliphatic ring system. Aliphatic isocyanates are those isocyanates containing only straight or branched chains; in other words, acyclic compounds. The monomeric isocyanate is preferably a diisocyanate having exactly two isocyanate groups.

[0106] In principle, higher isocyanates having an average of more than two isocyanate groups are also an option. Suitable examples of these isocyanates include triisocyanates such as nonane triisocyanate, ethyl 2'-isocyanate of 2,6-diisocyanate-hexanoate, toluene 2,4,6-triisocyanate, triphenylmethane triisocyanate, or diphenyl ether 2,4,4'-triisocyanate, or mixtures of diisocyanates, triisocyanates, and higher polyisocyanates, which are obtained, for example, by phosgenation of the corresponding aniline / formaldehyde condensate and constitute a polyphenyl polyisocyanate with methylene bridges. These monomeric isocyanates do not contain any substantial reaction products between the isocyanate groups and themselves.

[0107] The monomeric isocyanate is preferably an isocyanate having 4 to 20 carbon atoms. Typical examples of diisocyanates are aliphatic diisocyanates, such as tetramethylene diisocyanate, pentamethylene 1,5-diisocyanate, hexamethylene diisocyanate (1,6-diisocyanate hexane), octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, derivatives of lysine diisocyanate (e.g., methyl 2,6-diisocyanate hexanoate or ethyl 2,6-diisocyanate hexanoate), trimethylhexane diisocyanate, or tetramethylhexane diisocyanate; and alicyclic diisocyanates, such as 1,4-diisocyanate cyclohexane, 1,3-diisocyanate cyclohexane, etc. Cyclohexane cyanide or 1,2-diisocyanate cyclohexane, 4,4'-di(cyclohexyl isocyanate)methane or 2,4'-di(cyclohexyl isocyanate)methane, 1-trimethyl-5-(methyl isocyanate)cyclohexane (isophorone diisocyanate), 1,3-bis(methyl isocyanate)cyclohexane or 1,4-bis(methyl isocyanate)cyclohexane or 2,4-diisocyanate-1-methylcyclohexane or 2,6-diisocyanate-1-methylcyclohexane, and 3 (or 4), 8 (or 9) bis(methyl isocyanate)tricyclo[5.2.1.0] 2,6 [A mixture of decane isomers; and aromatic diisocyanates, such as 2,4-toluene diisocyanate or 2,6-toluene diisocyanate and mixtures of their isomers, m-phenylenedimethyl diisocyanate or p-phenylenedimethyl diisocyanate, 2,4'-diisocyanate diphenylmethane or 4,4'-diisocyanate diphenylmethane and mixtures of their isomers, 1,3-phenylene diisocyanate or 1,4-phenylene diisocyanate, 1-chloro-2,4-phenylene diisocyanate, 1,5-naphthylene diisocyanate, diphenyl 4,4'-diisocyanate, 4,4'-diisocyanate-3,3'-dimethylbiphenyl, 3-methyldiphenylmethane 4,4'-diisocyanate, tetramethylphenyldimethyl diisocyanate, 1,4-diisocyanate phenyl or diphenyl ether 4,4'-diisocyanate.] Particularly preferred are 1,6-hexamethylene diisocyanate, 1,3-bis(isocyanate-methyl)cyclohexane, isophorone diisocyanate, and 4,4'-di-(isocyanate-cyclohexyl)methane or 2,4'-di-(isocyanate-cyclohexyl)methane. Isophorone diisocyanate and 1,6-hexamethylene diisocyanate are very particularly preferred, and 1,6-hexamethylene diisocyanate is especially preferred. Mixtures of the mentioned isocyanates may also be present.

[0108] Isophorone diisocyanates are typically in the form of mixtures, particularly mixtures of cis and trans isomers, usually in a ratio of about 60:40 to 80:20 (w / w), preferably about 70:30 to 75:25, and more preferably about 75:25. Dicyclohexylmethane 4,4'-diisocyanate can also be in the form of mixtures of different cis and trans isomers.

[0109] Polyisocyanates formed from oligomeric isocyanates are typically characterized as follows: the average NCO functionality of such compounds is typically at least 1.8, and can be at most 8, preferably 2 to 5, and more preferably 2.4 to 4. Unless otherwise indicated, the content of the oligomeric isocyanate groups (calculated as NCO = 42 g / mol) is typically 5% to 25% by weight. Preferably, the polyisocyanate is a compound containing: 1) Polyisocyanates having an isocyanurate group and derived from aromatic, aliphatic, and / or cycloaliphatic diisocyanates. Particularly preferred here are corresponding aliphatic and / or cycloaliphatic isocyanate alkyl esters, and especially those based on hexamethylene diisocyanate and isophorone diisocyanate. These isocyanate esters of the present invention are particularly alkyl isocyanates and / or cycloalkyl isocyanates, which are cyclic trimers of diisocyanates, or mixtures with their higher homologues containing more than one isocyanurate ring. Isocyanate alkyl esters typically have an NCO content of 10% to 30% by weight, particularly 15% to 25% by weight, and an average NCO functionality of 2.6 to 8. 2) Polyisocyanates having a urea diketone group and an isocyanate group with aromatic, aliphatic, and / or cycloaliphatic bonds, preferably with aliphatic and / or cycloaliphatic bonds, and particularly those derived from hexamethylene diisocyanate or isophorone diisocyanate. Urea diketone diisocyanate is a cyclic dimer of diisocyanate. In the context of this invention, polyisocyanates having a urea diketone group are obtained as a mixture with other polyisocyanates, especially those mentioned in 1). For this purpose, diisocyanates are converted under reaction conditions to form urea diketone groups and other polyisocyanates, or urea diketone groups are first formed and these urea diketone groups are subsequently converted into other polyisocyanates, or diisocyanates are first converted into other polyisocyanates and these polyisocyanates are then converted into products containing urea diketone groups. 3) Polyisocyanates containing biuret groups, having aromatic, alicyclic, or aliphatic bonded isocyanate groups, particularly tris(6-isocyanate-hexyl) biuret or mixtures thereof with higher homologues. These polyisocyanates containing biuret groups preferably (especially in the case of HDI) have an NCO content of 18% to 23.5% by weight and an average NCO functionality of 2.8 to 6. 4) Polyisocyanates containing urethane and / or urea groups, having aromatic, aliphatic, or alicyclic bonds, preferably aliphatic or alicyclic bonds, can be obtained, for example, by reacting an excess of diisocyanate (e.g., hexamethylene diisocyanate or isophorone diisocyanate) with a monohydric or polyhydric alcohol (A). These polyisocyanates containing urethane and / or urea groups typically have an NCO content of 12% to 24% by weight and an average NCO functionality of 2.3 to 4.5. Such polyisocyanates containing urethane and / or urea groups can be prepared without catalysis, or preferably in the presence of a catalyst (such as ammonium carboxylate or ammonium hydroxide) or a urea esterification catalyst (such as a Zn(II) compound), in each case in the presence of a monohydric alcohol, dihydric alcohol, or polyhydric alcohol (preferably a monohydric alcohol). 5) Polyisocyanates containing an oxadiazine trione group, preferably derived from hexamethylene diisocyanate or isophorone diisocyanate. Such polyisocyanates containing an oxadiazine trione group can be obtained from diisocyanate and carbon dioxide. 6) Polyisocyanates containing an iminooxadiazine dione group, preferably derived from hexamethylene diisocyanate or isophorone diisocyanate. Such polyisocyanates containing an iminooxadiazine dione group can be prepared from diisocyanates, for example, using a specific catalyst. They are typically present in the form of a mixture with polyisocyanate 1), optionally also with 2) and / or 4). 7) Urea ketimide-modified polyisocyanates. 8) Carbodiimide-modified polyisocyanates. 9) Hyperbranched polyisocyanates, such as those known by DE-A1 10013186 or DE-A1 10013187. 10) Polyurethane-polyisocyanate prepolymers formed from diisocyanates and / or polyisocyanates with alcohols. 11) Polyurea-polyisocyanate prepolymer. 12) Polyisocyanates 1)-11), preferably 1), 3), 4), and 6), which, after their preparation, can be converted into polyisocyanates containing biuret groups or urethane / urethane groups having aromatic, alicyclic, or aliphatic, preferably (cyclic)-aliphatic, isocyanate groups. The biuret groups are formed, for example, by adding water or reacting with an amine. The urethane and / or urethane groups are formed by reacting with a monohydric alcohol, dihydric alcohol, or polyhydric alcohol (preferably a monohydric alcohol) optionally in the presence of a suitable catalyst. These polyisocyanates containing biuret or urethane / urethane groups typically have an NCO content of 18% to 22% by weight and an average NCO functionality of 2.8 to 6. 13) Hydrophilically modified polyisocyanates, that is, polyisocyanates that, in addition to the groups described in 1-12, are produced in a formal sense by adding molecules having NCO- reactive groups and hydrophilic groups to the isocyanate groups of the aforementioned molecules. The latter groups are nonionic groups (such as alkyl polyethylene oxide) and / or ionic groups derived from phosphoric acid, phosphonic acid, sulfuric acid, or sulfonic acid and / or their salts, exhibiting organic modification. They may be used atypically but according to the invention in solvent-based systems, more particularly as co-components of the isocyanate component. 14) Modified polyisocyanates for dual-curing applications, i.e., polyisocyanates produced in a formal sense by adding molecules having NCO reactive groups and groups that can be crosslinked by UV or photochemical radiation to the isocyanate groups of the aforementioned molecules, in addition to the groups described in 1-13. These molecules are, for example, hydroxyalkyl (meth)acrylates and other hydroxy-vinyl compounds.

[0110] The diisocyanates or polyisocyanates listed above may also be at least partially blocked. The classes of compounds used for blocking are described in DA Wicks, ZW Wicks, Progress in Organic Coatings, 36, 148-172 (1999), 41, 1-83 (2001) and 43, 131-140 (2001). Examples of classes of compounds used for blocking are phenols, imidazoles, triazoles, pyrazoles, oximes, N-hydroxyimides, hydroxybenzoates, secondary amines, lactams, CH-acidic cyclic ketones, malonates, or alkyl acetoacetates.

[0111] Preferred polyisocyanate crosslinking compounds are at least one polyisocyanate selected from the group consisting of isocyanurates, iminooxadiazine diones, biuret, urea diones, carbamates, and urethanes; preferably selected from the group consisting of isocyanurates, carbamates, and urethanes; more preferably selected from the group consisting of isocyanurates and urethanes; and particularly, polyisocyanates containing isocyanurate groups. In a particularly preferred embodiment, the polyisocyanate comprises a polyisocyanate containing isocyanurate groups and derived from 1,6-hexamethylene diisocyanate. In another particularly preferred embodiment, the polyisocyanate is a mixture of polyisocyanates containing isocyanurate groups and derived from 1,6-hexamethylene diisocyanate and isophorone diisocyanate.

[0112] Preferred polyisocyanate crosslinking compounds can be obtained by reacting at least one monomeric isocyanate, wherein the monomeric isocyanate is at least one monomeric isocyanate preferably selected from the group consisting of: 1,6-hexamethylene diisocyanate, 1,3-bis(isocyanate-methyl)cyclohexane, isophorone diisocyanate, and 4,4'-di(isocyanate-cyclohexyl)methane or 2,4'-di(isocyanate-cyclohexyl)methane, preferably 1,6-hexamethylene diisocyanate or isophorone diisocyanate.

[0113] Preferably, the polyisocyanate crosslinking agent has a viscosity of 1000 mPa s to 4000 mPa s (at 23°C, DIN ISO 3219) and a viscosity of 1000 seconds. -1 The shear rate D. Preferably, the polyisocyanate crosslinking agent has an NCO content of 15% to 20% (DIN ENISO 11909).

[0114] This invention provides a lamination method in which two substrates are bonded together, wherein a) Provide a first substrate in the form of a first film or paper. b) Provide a second substrate, which is selected from paper and may be the same as or different from the first film. c) Provide a two-component adhesive as described herein, and d) Apply the two-component adhesive to the first substrate and / or the second substrate, optionally allow it to dry, and laminate the first substrate onto the second substrate.

[0115] In the method according to the invention, the adhesive-coated article can be selected from, for example, a laminate, preferably in a method for bonding a large surface area substrate. The article is preferably a composite film or a glossy film. In the case of a composite film, at least two films are bonded together using an aqueous dispersion adhesive composition, wherein preferably one or both films are transparent. In the case of a glossy film, a transparent film is laminated onto paper or a card.

[0116] For applications in lamination methods, the laminating adhesive is preferably a non-self-adhesive. A non-self-adhesive is different from a pressure-sensitive adhesive, having only very low tack (if any) at room temperature and is preferably used under applied pressure and / or at elevated temperatures. The tack measured as ring tack is preferably less than 1.7 N / 25 mm (adhesive applied to a 12 μm thick polyester film at a thickness of 20 μm, measured on steel at a peel speed of 300 mm / min at room temperature (20°C).

[0117] A preferred method is a method for producing composite membranes, which includes bonding at least two membranes together using an aqueous laminating adhesive composition.

[0118] The laminating adhesive composition or correspondingly formulated preparation is preferably in the form of 0.1 g / m³. 2 Up to 20g / m 2 1 g / m 2 Up to 7g / m 2 or 1g / m 2 Up to 5g / m 2 A layer of a certain thickness is applied to a large surface area substrate to be bonded. After a short period of time (preferably after 1 to 60 seconds) of evaporation of the dispersed water, the coated substrate can then be laminated together with a second substrate, wherein the temperature can be, for example, from 20°C to 200°C, preferably from 20°C to 100°C, and the pressure can be, for example, 100 kN / m. 2 Up to 3000kN / m 2 Preferably 300kN / m 2 Up to 2000kN / m 2 .

[0119] In the method for composite film lamination according to the invention, at least two films are bonded to each other with a two-component lamination adhesive, wherein, as measured as described in the examples, the instantaneous peel force at 23°C is preferably greater than 1.0 N / 15 mm, and the peel force after 5 minutes at 65°C is greater than 4 N / 15 mm.

[0120] In the method according to the invention, at least one membrane in the film can be printed or metallized on the side coated with a laminating adhesive. Suitable film substrates are, for example, polymer films, particularly those made of: thermoplastic polyolefins (TPO) (such as polyethylene (PE), polypropylene (PP), for example oriented, preferably biaxially oriented polypropylene (OPP) or unoriented polypropylene (CPP)), ethylene / vinyl acetate copolymer (EVA), ASA (acrylonitrile / styrene / acrylate copolymer), PUR (polyurethane), polyamide (PA), polyester (preferably polyethylene terephthalate (PET)), polyvinyl chloride (PVC) (especially plasticized PVC), polyacetate, poly(meth)acrylate, polycarbonate or plastic alloys thereof, cellulose acetate, cellophane; polymer films coated with metal (e.g., aluminum) (by vapor deposition) (referred to as metallized films), such as, for example, metallized polyolefin films or metallized polyester films; or metal foils, for example, metal foils made of tin or aluminum. The membrane substrate is preferably selected from the group consisting of: polyethylene, oriented polypropylene, non-oriented polypropylene, polyamide, polyethylene terephthalate, polyacetate, cellophane, metallized film, and metal foil. The polymer membrane (especially the polyolefin membrane) may optionally have undergone corona pretreatment. The membrane (carrier membrane) is particularly preferably selected from polyethylene, oriented polypropylene, non-oriented polypropylene, polyamide, polyethylene terephthalate, polyacetate, and cellophane.

[0121] The listed films can be bonded to each other or to another type of film, such as polymer films bonded to metal foils, or different polymer films bonded together. The listed films can also be printed, for example, with printing inks. The thickness of the film substrate can be, for example, from 5 μm to 100 μm, preferably from 5 μm to 40 μm.

[0122] In the case of composite films, the material of the first film is preferably selected from OPP, CPP, PE, PET, and PA, and the material of the second film is preferably selected from OPP, CPP, PE, PET, PA, and metal foil. In one embodiment of the invention, the first film and / or the second film are printed or metallized on the respective sides coated with the dispersion adhesive composition.

[0123] The composite films obtained according to the present invention are particularly suitable for the production of flexible packaging, such as for food packaging.

[0124] Surface treatment of the membrane substrate is not absolutely necessary before laminating with the adhesive. However, better results can be obtained if the surface of the membrane substrate is modified before coating. In this case, conventional surface treatments can be used to enhance adhesion, such as primer, plasma treatment, or corona treatment. Corona treatment or other surface treatments are performed to the extent required for sufficient wetting of the coating composition. Typically, a corona treatment of about 10 watts per square meter per minute is sufficient for this purpose. Alternatively or additionally, a primer or bonding coating may be optionally used between the membrane substrate and the adhesive coating. Furthermore, other additional functional layers may be present on the composite membrane, examples of which are barrier layers, printed layers, coloring layers or varnish layers, or protective layers. These functional layers may be located externally, i.e., on the side of the membrane substrate facing away from the adhesive coating, or internally, between the membrane substrate and the adhesive layer.

[0125] A suitable exemplary applied weight for composite membrane production is: 0.1g to 20g, particularly preferably 1g to 7g, 1g to 6g or 1g to 5g solids / m 2 For other technical laminates: 0.5g to 100g, preferably 2g to 80g, very particularly preferably 10g to 70g solids / m 2 .

[0126] Besides composite film lamination, the method according to the invention can also be used in other industrial lamination methods, such as for the production of automotive interior parts, for furniture lamination, and for gloss film lamination. The substrates considered for bonding include those made of, for example, wood, metal, plastic, leather, fiber moldings (e.g., MDF sheets), or paper. In gloss film lamination, a transparent polymer film is bonded to a paper substrate.

[0127] When used for surface decoration of solid carriers having a film substrate (e.g., a decorative film) coated according to the invention, the film substrate coated according to the invention is, for example, bonded to articles made of wood, including bonded wood fiber materials such as fiberboard or other boards made of cellulose materials, metal, or plastic. For example, furniture or furniture parts are laminated with a coated film substrate, or automotive interior parts are coated with a coated film substrate made of, for example, PVC or TPO. Polyurethane dispersions are particularly suitable as adhesives for laminating rigid molded articles with flexible decorative films.

[0128] During lamination, the laminating adhesive is applied to the substrate surface areas to be bonded by means such as scraping, spreading, etc. Conventional coating techniques can be used, such as roller coating, reverse roller coating, gravure roller coating, reverse gravure roller coating, or flexographic coating. The coated substrate can then be laminated with a second substrate at a temperature, for example, from 20°C to 200°C, preferably from 20°C to 100°C, and at a pressure, for example, 100 kN / m. 2 Up to 3000kN / m 2 Preferably 300kN / m 2 Up to 2000kN / m 2 Before co-laminating the second substrate, the membrane coated with lamination adhesive is preferably passed through a dryer. The web speed of the membrane substrate is preferably from 50 m / min to 500 m / min, for example at least 100 m / min, for example from 100 m / min to 400 m / min or from 100 m / min to 300 m / min.

[0129] The subject of this invention also includes the use of two-component laminating adhesives as described herein for film-to-film lamination or for film-to-paper lamination.

[0130] The subject of this invention also includes laminated products produced according to the methods described herein, wherein the articles produced by the method are composite films, wherein at least two films are bonded to each other using a two-component laminating adhesive; or wherein the articles produced are glossy films, wherein a transparent film is bonded to a paper substrate. Example

[0131] Material :

[0132] Basonat ® LR9056 crosslinking agent; emulsifier-modified polyisocyanate based on isocyanurate-esterified hexamethylene diisocyanate.

[0133] Lupranol ® 1000 Polypropylene glycol with a molecular weight of 2000; OH value of 55 mg KOH / g (DIN 53 240) Example 1 (Comparison)

[0134] The aqueous polyacrylate dispersion according to Example 4 of WO 98 / 23656 is a polymer made of 56 wt% n-butyl acrylate, 28 wt% ethylhexyl acrylate, 10 wt% methyl methacrylate, 3 wt% styrene and 3 wt% acrylic acid; Tg: -34°C.

[0135] Add 2% by weight of Basonat ® LR9056 crosslinking agent Example 2 (Comparison)

[0136] The aqueous polyacrylate dispersion according to Example 5 of WO 98 / 23656 is a polymer made of 51 wt% n-butyl acrylate, 33 wt% ethylhexyl acrylate, 13 wt% styrene and 3 wt% acrylic acid; Tg: -34℃

[0137] Add 2% by weight of Basonat ® LR9056 crosslinking agent Example 3 (Comparison)

[0138] The aqueous polyacrylate dispersion according to Example 4 of WO 00 / 50480 is a polymer made of 84 wt% n-butyl acrylate, 15 wt% methyl methacrylate, and 1 wt% acrylic acid; Tg: -30℃

[0139] Add 2% by weight of Basonat ® LR9056 crosslinking agent Example 4 (Comparison)

[0140] Aqueous polyacrylate dispersions; polymers prepared by free radical emulsion polymerization of the following substances:

[0141] 57 wt% 2-ethylhexyl acrylate, 33 wt% styrene, 6 wt% 2-hydroxyethyl methacrylate, 2 wt% n-butyl acrylate, 2 wt% glycidyl methacrylate; Tg: -12℃

[0142] Add 2% by weight of Basonat ® LR9056 crosslinking agent Example 5 (Comparison)

[0143] Aqueous polyurethane dispersions: Polyurethanes made from the following substances:

[0144] 0.36 mol of propylene glycol (OH value 56), 0.79 mol of toluene diisocyanate (80% 2,4-isomer, 20% 2,6-isomer), and 0.43 mol of dimethylolpropionic acid were neutralized with 0.11 mol of NaOH.

[0145] The final solids content was 53%, and the pH was 7.

[0146] Add 2% by weight of Basonat ® LR9056 crosslinking agent Example 6

[0147] Aqueous polymer dispersions of polymer blends, with the following polymers in a 1:1 weight ratio:

[0148] First polymer: Polyacrylate polymer from Example 4

[0149] Second polymer: Polyurethane polymer from Example 5

[0150] Add 2% by weight of Basonat ® LR9056 crosslinking agent

[0151] TEGO ® Defoamer 2291 is administered at a ratio of 0.56 parts by weight of polymer per 100 parts by weight. Example 7

[0152] Aqueous polymer dispersions of polymer blends, with the following polymers in a 1:1 weight ratio:

[0153] First polymer: Polyacrylate produced by free radical emulsion polymerization of the following substances:

[0154] 79 wt% 2-octyl acrylate, 15 wt% styrene, 6 wt% 2-hydroxyethyl methacrylate; Tg: -25℃

[0155] Second polymer: Polyurethane polymer from Example 5

[0156] Add 2% by weight of Basonat ® LR9056 crosslinking agent Performance testing :

[0157] Membrane-to-membrane laminates are produced from two clear, transparent membranes.

[0158] The first membrane is a polyethylene terephthalate membrane with a thickness of 250 μm.

[0159] The second membrane is an 85μm thick polyethylene membrane.

[0160] Application weight: 2g / m 2 Up to 3g / m 2

[0161] Web speed: 19 m / min; pressure of 3 bar at room temperature (23°C)

[0162] A two-component laminated adhesive is prepared by mixing a polymer dispersion with a crosslinking agent. The two-component adhesive is then mixed at a concentration of 2 g / m². 2 Up to 3g / m 2The second film was applied onto the first film by weight. A pressure of 3 bar was applied at room temperature (23°C), and the second film was laminated onto the coated first film at a web speed of 9 m / min. For high-temperature peel force measurements, the film-to-film laminate was subsequently stored at room temperature under standard conditions (23°C, 50% relative humidity) for 24 hours. Peel force measurement

[0163] The membrane-to-membrane laminate was cut into 15 mm wide strips. The laminate strips were pulled apart on a Zwick tensile testing machine, and the force required to achieve this was recorded. The test was performed on the tensile testing machine at a 90-degree angle (T-test) and a removal speed of 100 mm / min. The test strip was opened on one side, with one end of the resulting strip clamped in the upper jaw of the tensile testing machine and the other end clamped in the lower jaw, and the test was started. The reported result is the average maximum force from three separate measurements, in N / 15 mm.

[0164] Instantaneous peel force is measured immediately after lamination at 23°C without storing the laminate.

[0165] High-temperature peel strength is the result of storing the laminate at room temperature for 24 hours under standard conditions, and then heating the laminate to 65°C for 5 minutes. Assessment of expansion and contraction risk, static shear strength

[0166] The stretching effect of the winding rollers of the laminate can be correlated with a static shear test at higher temperatures, as this is a measure of the flexibility of the adhesive film. This test is designed to measure the shear strength of the adhesive by applying a force parallel to the surface of the bonding material. Testing it without a crosslinking agent is more effective because the results are more pronounced, but can be correlated with the crosslinking system.

[0167] For this test, use 2g to 3g (dry) / m 2 An adhesive was applied to a PET film (250 μm thick), which was then laminated onto the PET film (250 μm) at room temperature and a lamination pressure of 3 bar. The length of the laminated area was 20 mm. After storing at room temperature for 24 hours, the laminate was cut into 15 mm wide test strips. To determine the shear strength, the test strips were subjected to suspension stress at 50°C with a weight of 0.5 kg. The shear strength was measured as the time required for the weight to drop.

[0168] The results are summarized in Table 1.

[0169] Table 1: Test Results

[0170]

[0171] A good peel force value is greater than 1.0 N / 15 mm for instantaneous peel force and greater than 4 N / 15 mm for high-temperature peel force. Data shows that Examples 6 and 7 provide high instantaneous peel force and high high-temperature peel force, while providing low risk of stretching. Comparative Examples 1 to 4 provide low risk of stretching but low peel force. Comparative Example 5 provides high peel force but also provides high risk of stretching.

Claims

1. A two-component laminating adhesive, wherein one component of the laminating adhesive is in the form of an aqueous polymer dispersion, the aqueous polymer dispersion comprising dispersed polymer particles of the following substances: (i) at least one first polymer, the first polymer being capable of being produced by radical emulsion polymerization of an olefinically unsaturated, radically polymerizable monomer, said olefinically unsaturated, radically polymerizable monomer comprising (a) Based on the total amount of monomers, at least 49% by weight, preferably 50% to 90% by weight, of at least one monomer selected from the group consisting of C2- to C12-alkyl acrylates and C2- to C12-alkyl methacrylates; (b) 5% to 50% by weight, preferably 9% to 40% by weight, of styrene based on the total amount of monomers; (c) Based on the total amount of monomers, 0.1% to 10% by weight, preferably 0.5% to 10% by weight, of at least one hydrophilic olefinic unsaturated monomer having at least one hydrophilic group selected from acid groups and hydroxyl groups, (d) Based on the total amount of monomers, 0% to 10% by weight of at least one other olefinic unsaturated monomer different from monomers a), b) and c), The glass transition temperature of the first polymer is greater than -30°C, preferably at least -25°C, more preferably -25°C to +5°C, and is measured by differential scanning calorimetry at a heating rate of 20°C / min. and (ii) at least one second polymer, wherein the second polymer is an adhesive polymer selected from polyurethane; Furthermore, the second component of the laminating adhesive comprises a crosslinking compound capable of crosslinking the first component.

2. The two-component laminated adhesive according to claim 1, wherein the weight ratio of the first polymer to the second polymer is 1:2 to 2:1, preferably 1:1.5 to 1.5:

1.

3. The two-component laminated adhesive according to claim 1 or 2, wherein monomer (a) is at least one monomer selected from the group consisting of: ethyl acrylate, propyl acrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, tert-butyl (meth)acrylate, n-hexyl acrylate, cyclohexyl (meth)acrylate, 2-octyl acrylate, 2-ethylhexyl acrylate and 2-propylheptyl acrylate.

4. The two-component laminated adhesive according to any one of claims 1 to 3, wherein monomer (c) is an olefinically unsaturated monomer having at least one acid group, and is at least one monomer selected from the group consisting of: acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, vinyl acetic acid, vinyl lactic acid, vinyl sulfonic acid, styrene sulfonic acid, acrylamidomethylpropanesulfonic acid, sulfopropyl acrylate, sulfopropyl methacrylate; or wherein monomer (c) is an olefinically unsaturated monomer having at least one hydroxyl group, and is selected from the group consisting of: hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate or hydroxypropyl methacrylate, 4-hydroxybutyl acrylate and 4-hydroxybutyl methacrylate.

5. The two-component laminate adhesive according to any one of claims 1 to 4, wherein monomer (d) is at least one monomer selected from the group consisting of: methyl acrylate, methyl methacrylate, vinyl esters of carboxylic acids comprising up to 20 carbon atoms, vinyl aromatic compounds having up to 20 carbon atoms, vinyl halides, vinyl ethers of alcohols comprising 1 to 10 carbon atoms, aliphatic hydrocarbons having 2 to 8 carbon atoms and one or two double bonds, acrylamide, methacrylamide, (meth)acrylic acid C1-C 10 Aminoalkyl esters, nitriles of α,β-mono-olefinic unsaturated C3-C8 carboxylic acids; bifunctional monomers having at least one group selected from glycidyl groups, oxazoline groups, urea groups and urea-like groups in addition to olefinic unsaturated double bonds; and crosslinking monomers having more than one group capable of free radical polymerization, more particularly two or more (meth)acrylate groups.

6. The two-component laminated adhesive according to any one of claims 1 to 5, wherein the first polymer can be produced by free radical emulsion polymerization of an olefinically unsaturated, free radically polymerizable monomer, the olefinically unsaturated, free radically polymerizable monomer comprising (a) Based on the total amount of monomers, 50% to 90% by weight of at least one monomer selected from the group consisting of: ethyl acrylate, propyl acrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, tert-butyl (meth)acrylate, n-hexyl acrylate, cyclohexyl (meth)acrylate, 2-octyl acrylate, 2-ethylhexyl acrylate and 2-propylheptyl acrylate. (b) 9% to 40% styrene based on total monomer content; (c) Based on the total amount of monomers, 0.5% to 10% by weight of at least one hydrophilic olefinic unsaturated monomer having at least one hydrophilic group selected from acid groups and hydroxyl groups, wherein the hydrophilic monomer is selected from the group consisting of: acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, vinyl acetic acid, vinyl lactic acid, vinyl sulfonic acid, styrene sulfonic acid, acrylamidomethylpropanesulfonic acid, sulfopropyl acrylate, sulfopropyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate or hydroxypropyl methacrylate, 4-hydroxybutyl acrylate and 4-hydroxybutyl methacrylate; (d) Based on the total amount of monomers, 0% to 10% by weight of at least one other olefinic unsaturated monomer different from said monomers a), b) and c).

7. The two-component laminated adhesive according to any one of claims 1 to 6, wherein the second polymer is polyurethane, said polyurethane being composed of: a) At least one monomeric diisocyanate b) at least one diol, wherein b1) Based on the total amount of diol (b), 10 mol% to 100 mol% having a molecular weight of 500 g / mol to 5000 g / mol, and b2) Based on the total amount of said diol (b), 0 mol% to 90 mol% has a molecular weight of 60 g / mol to 500 g / mol. c) At least one monomer different from monomers (a) and (b), said monomer having at least one isocyanate group or at least one isocyanate reactive group, and further having at least one hydrophilic group or potentially hydrophilic group, and d) Optionally, at least one other compound different from the monomers (a) to (c), said other compound having at least two reactive groups selected from an alcohol hydroxyl group, a primary amino group, a secondary amino group, or an isocyanate group, and e) Optionally, at least one monofunctional compound having a reactive group different from the monomers (a) to (d), wherein the reactive group is an alcohol hydroxyl group, a primary amino group, a secondary amino group, or an isocyanate group.

8. The two-component laminated adhesive according to any one of claims 1 to 7, wherein the diisocyanate a) is at least one diisocyanate selected from the diisocyanate of formula X(NCO)2, wherein X represents an acyclic aliphatic hydrocarbon group having 4 to 15 carbon atoms, an alicyclic hydrocarbon group having 6 to 15 carbon atoms, an aromatic hydrocarbon group having 6 to 15 carbon atoms, or an aryliphatic hydrocarbon group having 7 to 15 carbon atoms, preferably selected from the group consisting of hexamethylene diisocyanate, 5-isocyano-1-(isocyanomethyl)-1,3,3-trimethylcyclohexane, 2,6-diisocyanotoluene, 2,4-diisocyanotoluene, and tetramethylphenyl diisocyanate or mixtures thereof; Diol b1) is at least one diol selected from polyester diol, polycarbonate diol and polyether diol; and compound c) is at least one compound selected from dihydroxycarboxylic acid, diaminocarboxylic acid and diaminosulfonic acid.

9. The two-component laminated adhesive according to any one of claims 1 to 8, wherein the second polymer is characterized in that it is amorphous and / or has a K value between 20 and 80, and / or has a glass transition temperature between -60°C and -10°C, said glass transition temperature being measured by differential scanning calorimetry at a heating rate of 20°C / min.

10. The two-component laminated adhesive according to any one of claims 1 to 9, wherein the first polymer, the second polymer, or both are at least partially made of bio-based or recycled materials.

11. The two-component laminating adhesive according to any one of claims 1 to 10, wherein the crosslinking compound of the second component of the laminating adhesive is at least one compound selected from the group consisting of polyisocyanates and carbodiimides; The polyisocyanate is preferably at least one polyisocyanate selected from the group consisting of isocyanurate, iminooxadiazine dione, biuret, urea dione, carbamate, and urethane, and can be obtained by reacting at least one monomeric isocyanate, wherein the monomeric isocyanate is at least one monomeric isocyanate preferably selected from the group consisting of 1,6-hexamethylene diisocyanate, 1,3-bis(isocyanate methyl)cyclohexane, isophorone diisocyanate, and 4,4'-di(isocyanate cyclohexyl)methane or 2,4'-di(isocyanate cyclohexyl)methane, preferably 1,6-hexamethylene diisocyanate or isophorone diisocyanate; wherein the crosslinking compound of the second component of the laminating adhesive is used at a weight ratio of the crosslinking compound to the first polymer and the second polymer, preferably from 1 to 5 parts by weight of the total of 100 parts by weight of the polymer.

12. The two-component laminated adhesive according to any one of claims 1 to 11, wherein the instantaneous peel force measured at 23°C as described in the examples is greater than 1.0 N / 15 mm, and the peel force after 5 minutes at 65°C is greater than 4 N / 15 mm.

13. The two-component laminating adhesive according to any one of claims 1 to 12, wherein the first component of the two-component laminating adhesive is an aqueous composition, the aqueous composition comprising... (i) 25% to 70% by weight of the at least one first polymer; (ii) 25% to 70% by weight of the at least one second polymer; (iii) 0.25% to 5% by weight of one or more additives, preferably selected from the group consisting of: defoamers, preservatives, UV stabilizers, catalysts, desiccants, antistatic agents, flame retardants, thickeners, thixotropic agents, surfactants, viscosity modifiers, plasticizers, leveling agents, tackifiers, wetting agents, or chelating agents.

14. A lamination method in which two substrates are bonded together, wherein... a) Provide a first substrate in the form of a first film or paper. b) Provide a second substrate, the second substrate being selected from paper and a second film that may be the same as or different from the first film. c) Provide a two-component adhesive according to any one of claims 1 to 13, and d) Apply the two-component adhesive to the first substrate and / or the second substrate, optionally allow it to dry, and laminate the first substrate onto the second substrate.

15. The method according to the preceding claim, wherein the method is membrane-to-membrane lamination or membrane-to-paper lamination, and the material of the carrier membrane is selected from the group consisting of: polyethylene, oriented polypropylene, unoriented polypropylene, polyamide, polyethylene terephthalate, polyacetate, and cellophane.

16. A laminated product produced by the method according to any one of claims 14 to 15, wherein the article produced by the method is a composite film, wherein at least two films are bonded to each other using the two-component laminating adhesive; or wherein the article produced is a glossy film, wherein a transparent film is bonded to a paper substrate.

17. The use of the two-component laminating adhesive according to any one of claims 1 to 13 for film-to-film lamination or for film-to-paper lamination.

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