Mixtures of additives for the stabilization of adhesives, sealants and elastomers

Abstract

The present invention relates to concentrated aqueous polymer dispersions with an average particle size of less than 1000 nm, comprising a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b1) at least one stabilizer compound of formula (I), wherein o is an integer of 1 to 8; p is 0, or an integer of 1 to 8; q is 0, or 1; n is an integer 3, or 4; A is a 3, or 4 valent organic residue, which is selected from (C), Formula (II) and Formula (III) with the proviso that if A is an organic residue (C), o and p independently of one another are integers from 1 to 8; q is 1 and n is 4; and with the further proviso that. If A is an organic residue (Formula I) or (Formula II); o is an integer from 1 to 8; p is 0, q is 0 and n is 3; especially a stabilizer compound of formula (A-1); b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant; or comprising a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b1) at least one stabilizer compound of formula (I), especially compound (A-1), b3) a non-ionic, cationic or anionic surfactant, and a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant.

Description

[0001] Mixtures of additives for the stabilization of adhesives, sealants and elastomers

[0002] Description

[0003] The present invention relates to concentrated aqueous polymer dispersions with an average particle size of less than 1000 nm.

[0004] Prior Art

[0005] EP1251954B1 composition comprising particles which comprise a core material within a polymeric shell, wherein the core material comprises a hydrophobic substance, characterised in that the polymeric shell comprises a copolymer formed from a monomer blend which comprises,

[0006] A) 30 to 90% by weight methacrylic acid

[0007] B) 10 to 70% by weight alkyl ester of (meth)acrylic acid which is capable of forming a homopolymer of glass transition temperature in excess of 60°C and

[0008] C) 0 to 40% by weight other ethylenically unsaturated monomer.

[0009] W02005 / 023878A1 pertains to a concentrated aqueous dispersion of organic light stabilizers with a particle size of less than 1000 nm, prepared by heterophase radical polymerization of ethylenically unsaturated monomers in the presence of the light stabilizers, wherein the weight ratio of light stabilizer to polymeric carrier is greater than 50 / 100.

[0010] US20080146448 relates to an aqueous polymer dispersion with a mean particle size of the dispersed particles of less than 1000 nm, comprising the polymer particles comprising a polymer matrix formed from at least one ethylenically unsaturated monomer and at least one effect substance which is soluble in the ethylenically unsaturated monomers from which the polymers are formed, wherein the dispersed polymer particles comprise at least 0.1% by weight of at least one polymer selected from the group consisting of

[0011] (i) homopolymers of ethylene, propylene, 1 -butene, 2-butene, 1 -pentene or 1 -hexene with an average molar mass MW from 100 to 10 000,

[0012] (ii) copolymers of at least two of the monomers mentioned under (i) with an average molar mass MW from 100 to 10 000 and

[0013] (iii) polyisobutylene with an average molar mass MW of at least 100. The effect substances are selected from the group consisting of UV absorbers, IR absorbers, organic colorants, optical brighteners, antioxidants for polymers, antifogging agents for polymers, antistatic agents for polymers, flame retardants for polymers, lubricants for polymers, reactive sizing agents for paper, pharmaceutical active substances, biocides, fungicides, herbicides, nematicides, acaricides, insecticides, safeners and active substances which regulate plant growth.

[0014] WO2011 / 012631A1 pertains to a concentrated aqueous polymer dispersion with an average particle size of less than 1000 nm comprising a polymer carrier, a non-polar organic phenolic antioxidant and a surfactant. WO2011 / 012631 A1 also pertains to a process for the preparation of said concentrated aqueous polymer dispersion, to a polymer powder obtainable from said concentrated aqueous polymer dispersion, to a composition comprising an organic material and said concentrated aqueous polymer dispersion or said polymer powder and to the use of said concentrated aqueous polymer dispersion or said polymer powder as stabiliser for organic material.

[0015] WO2012 / 104287 aims to improve temperature resistance for a curable composition based on a silyl-terminated polymer. This is achieved by using a combination of at least two phenolic compounds, of which one is free of thioether groups, while the other contains at least one thioether group in at least one alkyl side chain. The invention further relates to the use of the curable composition as an adhesive, sealant and / or coating substance and to the use of the combination of phenolic compounds to increase the temperature stability in curable compositions.

[0016] WO201942999A1 relates to aqueous polymer dispersions with an average particle size of less than 1000 nm comprising a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of

[0017] (b) an oil-soluble organic UV absorber selected from the class of p-aminobenzoic acid derivatives; salicylic acid derivatives; benzophenone derivatives; diphenyl acrylate derivatives; benzofuran derivatives; polymeric UV absorbers, comprising one or more orga- nosilicon radicals; cinnamic acid derivatives; camphor derivatives; s-triazine derivatives; trianilino-s-triazine derivatives; menthyl anthranilates; and benzotriazole derivatives; wherein the weight ratio of the oil-soluble organic UV absorber (b) to polymer carrier (a) is greater than 50 parts UV absorber per 100 parts of carrier; and c) a surfactant selected from ci) a nonionic surfactant selected from en) the condensation product of a C6 to C18 fatty alcohol or C6 to C18 fatty acid and a mono- or disaccharide; and

[0018] C2) an anionic surfactant selected from

[0019] C21) sulfosuccinates and sulfosuccinamates;

[0020] C22) fatty alcoholates; and

[0021] C23) mixtures of phosphoric acid esters and fatty alcohols having from 6 to 18, preferably from 8 to 10, carbon atoms. The aqueous polymer dispersions show unexpectedly high sunscreen effects and a positive skin feeling.

[0022] KR20230060490A provides an aqueous dispersion of an antioxidant for latex which comprises an acrylic resin (A), an anionic surfactant (B), a phenolic antioxidant (C), polyhydric alcohol (D), and a saponifier (E), a mixture containing the aqueous dispersion of the antioxidant for latex and a molded product manufactured therefrom.

[0023] WO2023 / 280754 relates to a composition (S) comprising a. microfibrillar cellulose (A); b. at least one stabilizer compound (B) having at least one thioether functional group; and c. at least one component (C), wherein the at least one stabilizer compound (B) is absorbed on the microfibrillar cellulose (A) and the absorbed stabilizer compound (B) is at least partly coated with component (C).

[0024] There is often the need for the stabilization of water borne adhesives and sealants vs. temperature exposure. This is for example important in graphic arts and protective foils where the adhesive is exposed to heating under sun. Similar problems arise in automotive applications, such as, for example, interior laminations in cars and floorings with heat exposure by floor heating systems.

[0025] Utilizing antioxidants, like hindered phenols, or phosphites for stabilization is not possible, as most of the antioxidants are not soluble in water.

[0026] Therefore, different dispersions / emulsions from antioxidants are used to make the antioxidants accessible to the adhesives in sealants. The high surfactant load of said dispersions / emulsions is often giving raise to adhesive failures.

[0027] Accordingly, it was the object of the present invention to provide antioxidants which result in better stabilization performance as compared to dispersed or emulsified antioxidants, in particular better tack retention and lesser impact on initial adhesion values. In addition, better shear adhesion results and less loss of mechanical properties should be obtained.

[0028] It has now been found that various solvent-based (SB), acrylic latex types and polyurethane dispersion (PUDs) can be stabilized by the use of encapsulated mixtures of antioxidants. This approach does not only stabilize the polymer to a better extend, but is also preferred for pressure sensitive adhesives based on acrylic dispersions and laminating adhesives based on PU dispersions, respectively the mixture of these dispersions as they are used to fabricate different adhesives in the target applications. The advantage of utilizing acrylic based encapsulated stabilizers is a better transparency of a film after film formation, i.e. better distribution of the antioxidant in the film; a significant improvement in color stabilization and can be particularly assessed by the adhesion values as these are suffering from oxidation even before a color change can be observed.

[0029] The acrylic based encapsulated antioxidants result in better stabilization performance as compared to dispersed or emulsified antioxidants, in particular better tack retention and lesser impact on initial adhesion values. In addition, better shear adhesion results and less loss of mechanical properties are obtained.

[0030] It is possible to either use a mixture of the two phenolic antioxidants (stabilizer compound(s) of formula (I) and stabilizer compound(s) (B)) in separate capsules, or a mixture of the two phenolic antioxidants in one capsule. Better results are achieved by the second approach. Surprisingly the combination of two phenolic antioxidants is giving better results in the stabilization of PUD’s than the individual antioxidants over a broad variety of PUDs.

[0031] Accordingly, the present application is directed to concentrated aqueous polymer dispersions with an average particle size of less than 1000 nm (i.e. droplets of ethy len ically unsaturated monomer and phenolic antioxidants with an average particle size of less than 1000 nm), comprising a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b1) at least one stabilizer compound of formula

[0032] (I), wherein o is an integer of 1 to 8; p is 0, or an integer of 1 to 8; q is 0, or 1 ; n is an integer 3, or 4;

[0033] A is a 3, or 4 valent organic residue, which is selected from with the proviso that if A is an organic residue , o and p independently of one another are integers from 1 to 8; q is 1 and n is 4; and with the further proviso that from 1 to 8; p is 0, q is 0 and n is 3; especially a stabilizer compound of formula b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant; or concentrated aqueous polymer dispersions with an average particle size of less than 1000 nm, comprising a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b1) at least one stabilizer compound of formula (I), especially compound (A-1), b3) a non-ionic, cationic or anionic surfactant, and a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant.

[0034] The polymer dispersions of the present invention release the antioxidant(s) on an atomic level into the adhesive film upon film formation. Therefore, the antioxidant(s) have much higher efficiency as compared to dispersed antioxidant(s).

[0035] Said higher efficiency is demonstrated by better retention of color and physical values. In addition, the surfactant load is dramatically reduced. This results in better adhesive values even before aging. In a preferred embodiment of the present invention the compound of formula (I) is a compound of formula and p independently of one another are integers from 1 to 8; especially a stabilizer compound of formula

[0036] In another preferred embodiment of the present invention the compound of formula (I) is a compound of formula o is an integer of 1 to 8, especially 1 , or 2;

[0037] A is a 3 valent organic residue, which is selected from

[0038] ; especially a stabilizer compound of formula

[0039]

[0040] The stabilizer (B) according to the present invention is a thioether compound having a melting point of less than 100 °C, more preferably the stabilizer (B) is a thioether compound having a melting point of less than 80 °C, even more preferably the stabilizer (B) is a thioether compound having a melting point of less than 50 °C, most preferably the stabilizer (B) is a thioether compound having a melting point of less than 40 °C, and in particular the stabilizer (B) is a thioether compound liquid at room temperature and atmospheric pressure.

[0041] In a preferred embodiment of the present invention the at least one stabilizer (B) is selected from the group consisting of compounds of formula

[0042] (II), where Rdis an unsubstituted Ci-C8alkyl group, Rband Rc, independently of one another, are linear Ci-C2oalkyl groups and n' and m', independently of one another, are integers from 1 to 8, in particular Rdis a methyl, ethyl or i-propyl group, n' and m' are 1 and Rband Rcare each a C8-Ci3alkyl group, with Rband Rccomprising preferably the same number of C atoms.

[0043] Examples of the stabilizer (B) are shown below:

[0044] The at least one stabilizer compound (B) is preferably selected from the group consisting of cpd. (B-1), cpd. (B-2), cpd. (B-3), cpd. (B-4), cpd. (B-5), cpd. (B-6), cpd. (B-7), cpd. (B-8), cpd. (B-9) and mixtures thereof. Cpd. (B-1), cpd. (B-2), cpd. (B-3), cpd. (B-4), cpd. (B-5), cpd. (B- 6), cpd. (B-7) and mixtures thereof are more preferred, cpd. (B-1), cpd. (B-2), cpd. (B-3) and mixtures thereof are even more preferred, cpd. (B-1), cpd. (B-2) and a mixture thereof are most preferred.

[0045] In a particularly preferred embodiment the concentrated aqueous polymer dispersion comprises a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b1) a stabilizer compound of formula (A-1), b2) a stabilizer compound b3) a non-ionic, cationic or anionic surfactant, especially an anionic surfactant.

[0046] Anionic surfactants are preferred. Examples for anionic surfactants are alkali and ammonium salts of sulphonic acid (e.g. Ci2-Ci8alkylsulfonic acid), mono- or dialkylsulfosuccinates, or sulfuric acid halfesters of ethoxylated alkanoles, especially poly(oxy-1 ,2-ethanediyl), a-sulfo- o-hydroxy-, Ci2-i4-alkyl ethers, sodium salts (CAS no. 68891-38-3).

[0047] The ratio of the stabilizer compound of formula (I) and the stabilizer compound (B) is preferably in the range of from 80:20 to 20:80, more preferably in the range of from 60:40 to 40:60.

[0048] For instance, the weight ratio of stabilizer compound(s) to polymer carrier is equal or greater than 50 parts per 100 parts of carrier, preferably equal or greater than 80 parts per 100 parts of carrier, most preferably equal or greater than 90 parts per 100 parts of carrier. For instance, the weight ratio of stabilizer compound(s) to polymer carrier is equal or greater than 50 parts per 100 parts of carrier, preferably equal or greater than 80 parts per 100 parts of carrier, most preferably equal or greater than 90 parts per 100 parts of carrier.

[0049] For instance, the weight ratio of stabilizer compound(s) to polymer carrier is equal or lower than 1900 parts per 100 parts of carrier, preferably equal or lower than 900 parts per 100 parts of carrier, more preferably equal or lower than 300 parts per 100 parts of carrier, most preferably equal or lower than 200 parts per 100 parts of carrier.

[0050] For instance, the average particle size is less than 500 nm, preferably less than 250 nm. For instance, the minimum average particle size is 25 nm, preferably 50 nm.

[0051] Droplet (oil / water emulsion) as well as particle (polymer dispersion) size can be measured by using dynamic light scattering (DLS) technique (also known as photon correlation spectroscopy (PSC) or quasi-elastic light scattering (QELS)). For this kind of measurement a NICOMP particle sizer (NICOMP Model 380, Particle Sizing System, Santa Barbara, CA, USA) with a fixed scattering angle of 90° can be used for example. The measurement leads to the mean diameter DINT (intensity weighted). For instance, the average particle size is the mean intensity diameter determined by dynamic light scattering at 90° scattering angle.

[0052] For example, the residual monomer content of the polymer carrier is below 500 ppm, preferably below 250 ppm, more preferably below 100 ppm, most preferably below 50 ppm.

[0053] For example, the residual monomer content of the polymer carrier is the residual content of ethylenically unsaturated monomer. For instance, the residual monomer content of the polymer carrier is equal to or greater than 0 ppm.

[0054] The total solids content of the concentrated aqueous polymer dispersion is for example more than 20%, for instance more than 30% and preferably more than 35 % by weight based on the total weight of the aqueous dispersion. The total solids content of the concentrated aqueous polymer dispersion is for instance less than 95%, for example less than 80%, especially less than 60% by weight based on the total weight of the aqueous dispersion.

[0055] Preferably more than one ethylenically unsaturated monomer is used. When the polymerization is carried out with two or more monomers, at least one may carry two unsaturated functionalities in order to provide a certain degree of crosslinking. For example, the amount of the difunctional monomer may vary from 0.5 to 20 % by weight based on the total weight of the monomer mixture.

[0056] Preferably the ethylenically unsaturated monomer is selected from the group consisting of (alkyl)acrylic acid, (alkyl)acrylic ester, alkanediol diacrylate and mixtures thereof. Mixtures thereof are particularly preferred. Examples for specific ethylenically unsaturated monomers are n-butylmethacrylate, tertbutylmethacrylate, methylacrylate, ethylmethacrylate, propylmethacrylate, hexylmethacrylate, 1 ,4-butanediol dimethacrylate, ethylene glycol dimethacrylate or hydroxyethylmethacrylate, ethylhexyl methacrylate, iso-butylmethacrylate, cyclohexylmethacrylate, methylmethacrylate, stearylmethacrylate, acrylic acid, methacrylic acid, benzylmethacrylate, vinyl toluene, ethylhex-ylacrylate, iso-butylacrylate, benzylacrylate, cyclohexylacrylate, hydroxyethylacrylate, methylacrylate, stearylacrylate, n-butylacrylate, tert-butylacrylate, methylacrylate, ethylacrylate, propylacrylate, hexylacrylate, 1 ,4-butanediol diacrylate, ethylene glycol diacrylate or hydroxyethylacrylate, especially methylmethacrylate, stearylmethacrylate, butanediol diacrylate and methacrylic acid.

[0057] A particular suitable monomer mixture is a mixture of methylmethacrylate, stearylmethacrylate, butanediol diacrylate and methacrylic acid.

[0058] Acrylic acid esters and methacrylic acid esters are typically Ci-C2oalkyl esters.

[0059] For example, the ethylenically unsaturated monomer is selected from the group consisting of Ci-C2oalkyl acrylates, Ci-C20alkyl methacrylates, acrylic acid, methacrylic acid, styrene, vinyltoluene, hydroxy-functional acrylates or methacrylates, acrylates or methacrylates derived from alkoxylated alcohols and multifunctional acrylates or methacrylates or mixtures thereof.

[0060] Particularly useful methacrylates are methylmethacrylate and stearylmethacrylate.

[0061] In a specific embodiment the concentrated aqueous polymer dispersion is prepared from a mixture of at least two of the above monomers and at least one monomer which is bifunctional, so that a crosslinked polymer is obtained. The amount of bifunctional monomer is for example from 0.5 to 20 weight-%, based on the weight of the sum of monomers.

[0062] Typical examples for bifunctional monomers are divinyl-benzene, ethylenglycol diacrylate, butanediol diacrylate, 1 ,4-butanediol dimethacrylate, ethylene glycol dimethacrylate, diethyleneglycol dimethacrylate or diethyleneglycol diacrylate, especially butanediol diacrylate.

[0063] Another aspect of this invention is a process for the preparation of a concentrated aqueous polymer dispersion with an average particle size of less than 1000 nm comprising the steps polymerizing at least one ethylenically unsaturated monomer in the presence of b1) at least a stabilizer compound of formula (I) defined in claim 1 ; b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant by heterophase radical polymerization; or a process comprising the step(s) polymerizing at least one ethylenically unsaturated monomer in the presence of b1) at least a stabilizer compound of formula (I) defined in claim 1 ; b3) a non-ionic, cationic or anionic surfactant by heterophase radical polymerization, and polymerizing at least one ethylenically unsaturated monomer in the presence of b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C by heterophase radical polymerization; and b3) a non-ionic, cationic or anionic surfactant.

[0064] The surfactant can be a non-ionic, cationic or anionic surfactant (preferably a non-ionic or anionic surfactant). The polymerisation is preferably a by heterophase radical polymerization.

[0065] The weight ratio of stabilizer compound(s) to polymer carrier formed from the ethylenically unsaturated monomer is equal to or greater than 30 parts of stabilizer compound(s), per 100 parts of polymer carrier and for instance, the residual monomer content of the polymer carrier after the polymerisation is below 2000 ppm.

[0066] For instance, the process comprises the steps i) dissolving, emulsifying or dispersing the stabilizer compound(s) in at least one ethylenically unsaturated monomer; ii) preparing a conventional oil in water emulsion of said stabilizer compound(s) dissolved, emulsified or dispersed in at least one ethylenically unsaturated monomer in the presence of a non-ionic, cationic or anionic surfactant; iii) homogenizing the conventional emulsion to a miniemulsion wherein the droplets of the organic phase have an average diameter below 1000 nm; iv) polymerizing the miniemulsion by adding a polymerization initiator.

[0067] For instance, the product of the heterophase polymerisation process has a solids content of at least 20%, preferably at least 30%, most preferably at least 35 %. For example, the product of the heterophase polymerisation process has a solids content of up to 90%.

[0068] Typically, the particle size distribution of the small droplets of ethylenically unsaturated monomer and stabilizer compound(s) does not substantially change during polymerisation.

[0069] Optionally other water miscible solvents may be present usually 0.01-100%, especially 5- 100% by weight based on the stabilizer compound(s) content. Exemplary co-solvents useful in the present invention may be selected from the group consisting of aliphatic alcohols, glycols, ethers, glycol ethers, pyrrolidines, N-alkyl pyrrolidinones, N-alkyl pyrrolidones, polyethylene glycols, polypropylene glycols, glycerol, amides, carboxylic acids and salts thereof, esters, organosulfides, sulfoxides, sulfones, alcohol derivatives, hydroxyether derivatives such as butyl carbitol or cellosolve, amino alcohols, ketones, and the like, as well as derivatives thereof and mixtures thereof. Specific examples include methanol, ethanol, propanol, dioxane, ethylene glycol, propylene glycol, diethylene glycol, glycerol, dipropylene glycol, tetra hydrofuran, and other water-soluble or water-miscible materials, and mixtures thereof. For instance, depending on the intended and application the water miscible solvent remains in the product form or is removed after the polymerisation by e.g. vacuum distillation.

[0070] Preferred are water, water alcohol mixtures, water ethylene glycol or propylene glycol mixtures, water acetone, water tetrahydrofurane, water glycerol or water dimethylformamide mixtures, especially water, in particular water without an organic solvent, such as water without a water-miscible solvent.

[0071] In a special process variant, a preformed polymer is added to the stabilizer compound(s) and monomer in process step i), ii) and / or iii). This polymer may preferably be soluble in the monomer and may support the process steps i), ii) and / or iii), i.e. may support the formation of a nanodisperse emulsion of stabilizer compound(s) and monomer in water.

[0072] Suitable surfactants or surface active compounds, which may be added are known in the art. The amounts typically used range from 0.01% by weight to 10.0% by weight, especially from 2.0 % by weight to 8.0% by weight, very especially from 3.0 % by weight to 7.0% by weight, based on total amount of monomer(s) and active substance(s) (i.e. stabilizer compound of formula (I) and stabilizer compound (B) and optionally further additives comprised by the polymer carrier, such as, for example, the light stabilizer of formula and / or the light stabilizer of formula

[0073] In said case the heterophase radical polymerization of at least one ethylenically unsaturated monomer is done in the presence of components (b1), (b2), (b3) and in addition (b4) at least one light stabilizer which is selected from light stabilizers of formula

[0074] (III), wherein r halogen;

[0075] R5and R8are independently of each other hydrogen, or Ci-C20alkyl, especially hydrogen;

[0076] Z is hydrogen, C2-C20alkenyl, or said C2-C20alkenyl, substituted by one to three — R44, — OR45, — COOR45, — OCOR45and / or interrupted by one to three — O — , — COO — , — OCO — or — CO — ; especially Ci-C24alkyl or C5-Ci2cycloalkyl; or said Ci-C24alkyl or said C5- Ci2cycloalkyl substituted by one to three — R44, — OR45, — COOR45, — OCOR45and / or interrupted by one to three — O — , — COO — , — OCO — or — CO — ;

[0077] R44is C6-Cioaryl, C6-Ci0aryl substituted by one to three halogen, Ci-C8alkyl, Ci-C8alkoxy, or combinations thereof; C5-Ci2cycloalkyl; C7-Ci2phenylalkyl, C7-Ci2phenylalkyl substituted on the phenyl ring by one to three halogen, Ci-C8alkyl, Ci-C8alkoxy, or combinations thereof; R45is defined as is R44; or R45is also hydrogen or Ci-C24alkyl;

[0078] Ar2and Ar3are independently of each other selected from a group of the formula (D-2),

[0079] (D-3), phenyl or phenyl substituted by one to three Ci-C6alkyl, halogen, hydroxy or Ci-Ci2alkoxy; naphthyl or naphthyl substituted by one to three Ci-

[0080] C6alkyl, halogen, hydroxy or Ci-Ci2alkoxy; and (D-4);

[0081] R51, R52, R53, R54and R55are independently of each other hydrogen, hydroxy, cyano, Ci- C20alkyl, Ci-C20alkoxy, C7-Ci2phenylalkyl, C5-Ci2cycloalkyl, C5-Ci2cycloalkyloxy, or halogen; Z’ is as defined for Z; R6is as defined for R6, R5and R8are as defined for R5and R8, respectively; and light stabilizers of formula wherein

[0082] R1is hydrogen, Ci-Ci8alkyl, or Ci-Ci8alkyl which is substituted by phenyl, R2is hydrogen, Ci-Ci8alkyl, or is Ci-Ci8alkyl which is substituted by COOR25, Ci-Ci8alkoxy, hydroxyl, phenyl or C2-Ci8acyloxy; R3is hydrogen, halogen, Ci-Ci8alkyl, Ci-Ci8alkoxy, C2-Ci8acyloxy, phenyl, or is Ci- Ci2fluoroalkyl;

[0083] R4is hydrogen, halogen, Ci-Ci8alkyl, Ci-Ci8alkoxy, C2-Ci8acyloxy, phenyl, or is Ci-

[0084] Ci2fluoroalkyl; or

[0085] R3and R4together form a ring;

[0086] R25is hydrogen, Ci-Ci8alkyl or C4-C5oalkyl interrupted by one or more O and / or substituted by OH, or by , wherein R1, R3and R4are defined above.

[0087] The light stabilizer of formula (III) is preferably selected from 2-(4,6-diphenyl-1 ,3,5-triazin-2- yl)-5-(hexyloxy)-phenol, 2-(4,6-bis-(2,4-dimethylphenyl)-1 ,3,5-triazin-2-yl)-5-(octyloxy)- phenol, 2-[4,6-Bis(2,4-dimethylphenyl)-1 ,3,5-triazin-2-yl]-5-[3-(dodecyloxy)-2- hydroxypropoxy]phenol and 2-[4,6-bis(2,4-dimethylphenyl)-1 ,3,5-triazin-2-yl]-5-[2-hydroxy-3- (tridecyloxy)propoxy]phenol, 2-[4,6-bis(2,4-dimethylphenyl)-1 ,3,5-triazin-2-yl]-5-[3-[(2- ethylhexyl)oxy]-2-hydroxypropoxy]phenol, 2-[4,6-Bis([1 ,1'-biphenyl]-4-yl)-1 ,3,5-triazin-2-yl]-5- [(2-ethylhexyl)oxy]phenol, 2-[2-hydroxy-4-(1-octyloxycarbonylethyl)oxyphenyl]-4,6-di(4- phenyl)phenyl-1 ,3,5-triazine, 2,4,6-tri(2,4-dihydroxyphenyl)-1 ,3,5-triazine, 2,4-bis[2-hydroxy- 4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1 ,3,5-triazine, 2,2'-[6-(4-methoxyphenyl)-1 ,3,5- triazine-2,4-diyl]bis(5-((2-ethylhexyl)oxy)-phenol, 2,4,6-tris-(2'-hydroxy-4'-butoxyphenyl)- 1 ,3,5-triazine, 2,2',2"-(1 ,3,5-triazine-2,4,6-triyl)tris[5-(octyloxy)phenol], 2,4,6-tris(2-hydroxy-4- hexyloxy-3-methylphenyl)-1 ,3,5-triazine, 2-[4,6-bis(2,4-dimethylphenyl)-1 ,3,5-triazin-2-yl]-5- [2-hydroxy-3-(tridecyloxy)propoxy]-phenol, 2,4,6-tris[4-(1-octyloxycarbonyl)ethyloxy-2- hydroxyphenyl]-1 ,3,5-triazine, 1 ,1 '-dioctyl 2,2'-[[4-[4,6-bis[2-hydroxy-4-[1-methyl-2-(octyloxy)- 2-oxoethoxy]phenyl]-1 ,3,5-triazin-2-yl]-1 ,3-phenylene]bis(oxy)]bis[propanoate], 2,4-bis(2,4- dihydroxyphenyl)-6-(4-methoxyphenyl)-1 ,3,5-triazine, 2-(2,4-dihydroxyphenyl)-4,6-diphenyl- 1 ,3,5-triazine, 2,6-bis(2,4-dimethylphenyl)-4-(2,4-dihydroxyphenyl)-s-triazine, 4-[4,6-bis([1 , 1 '- biphenyl]-4-yl)-1 ,3,5-triazin-2-yl]-1 ,3-benzenediol and 2,4,6-tris(2,4-dihydroxy-3- methylphenyl)-1 ,3,5-triazine and 2, 4, 6-tribiphenyl-4-yl- 1 ,3,5-triazine.

[0088] The light stabilizer of formula (IV) is preferably selected from 2-(benzotriazol-2-yl)-4- methylphenol, 2-(2'-hydroxy-3',5'-di-t-butyl-phenyl)benzotriazole, 2-(5-chlor-2H-benzotriazol- 2-yl)-4-methylphenol, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2H- benzotriazol-2-yl)-4,6-di-tert-pentylphenol, 2-(2'-hydroxy-5'-(1 ,1 ,3,3- tetramethylbutyl)phenyl)benzotriazole, 2-(benzotriazol-2-yl)-6-butan-2-yl-4-tert-butylphenol, 2,2'-methylenebis(6-(2H-benzotriazol-2-yl)-4-(1 ,1 ,3,3-tetramethylbutyl)phenol), 2-(2H- benzotriazol-2-yl)-6-dodecyl-p-cresol, 2-(2-benzotriazolyl)-6-dodecyl-4-methylphenol, polyethylene glycol di[3-[3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]-1 -oxopropyl] ether, 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol, 2-(2H-benzotriazol-2- yl)-6-(1 -methyl- 1-phenylethyl)-4-(1 ,1 , 3, 3-tetramethylbutyl)phenol, 3-(2H-benzotriazol-2-yl)-5- (1 ,1-dimethylethyl)-4-hydroxybenzenepropanoic acid, a-[3-[3-(2H-benzotriazol-2-yl)-5-(1 ,1- dimethylethyl)-4-hydroxyphenyl]-1-oxopropyl]-w-hydroxypoly(oxy-1 ,2-ethanediyl), octyl 3-[3- (2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionate, octyl 3-[3-(2H-Benzotriazol-2- yl)-5-tert-butyl-4-hydroxyphenyl]propionate, 6-butyl-2-[2-hydroxy-3-(2-phenyl-2-propyl)-5- (2,4,4-trimethyl-2-pentyl)phenyl]-[1 ,2,3]triazolo[4,5-f]isoindole-5,7(2H,6H)-dione, 6-butyl-2-[2- hydroxy-3-(1-methyl-1-phenylethyl)-5-(1 ,1 ,3,3-tetramethylbutyl)phenyl]pyrrolo[3,4- f]benzotriazole-5,7(2H,6H)-dione, octyl 3-[3-tert-butyl-5-(5-chlorobenzotriazol-2-yl)-4- hydroxyphenyl]propanoate, 2-(benzotriazol-2-yl)-4-(2,4,4-trimethylpentan-2-yl)phenol, 3-[3- (2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid, methyl 3-[3-tert-butyl-5- (2H-benzotriazol-2-yl)-4-hydroxyphenyl]propionate, 2-[3-(2H-benzotriazol-2-yl)-4- hydroxyphenyl]ethyl methacrylate and 2-(2H-benzotriazol-2-yl)-4-methyl-6-[2-methyl-3- [1 ,3,3,3-tetramethyl-1-[(trimethylsilyl)oxy]-1-disiloxanyl]propyl]phenol.

[0089] One or more of the mentioned compounds may exist in one or more isomeric or polymorphic forms, one or more of which may reveal an improved activity. Such forms or isomers are considered to be included within the scope of the present invention. Purification and isolation to yield one or more of such preferred isomers or forms is considered within the scope of this application.

[0090] Further additives which may be encapsulated are the compounds of formula (I) as described in EP3019474B1.

[0091] Examples for anionic surfactants are alkali and ammonium salts of sulphonic acid (e.g. Ci2- Ci8alkylsulfonic acid), mono- or dialkylsulfosuccinates, or sulfuric acid halfesters of ethoxylated alkanoles, especially poly(oxy-1 ,2-ethanediyl), a-sulfo-o-hydroxy-, Ci2-i4-alkyl ethers, sodium salts (CAS no. 68891-38-3). Some compounds are known for example from US4269749 and largely items of commerce, such as under the trade name Dowfax® 2A1 (Dow Chemical Company). Nonionic surfactants are for example aliphatic or araliphatic compounds such as ethoxylated phenols (mon, di, tri) with an ethoxylation degree of 3 to 50 and alkyl groups in the range from C4-C9, ethoxylated long chain alcohols or polyethyleneoxide / polypropyleneoxide block copolymers.

[0092] Furthermore, protective colloids such as polyvinylalcohols, starch, cellulose derivatives or copolymers containing vinylpyrrolidone may be added to form a conventional oil in water emulsion according to step B). Further examples are given in “Houben-Weyl, Methoden der Organischen Chemie, Band XIV / 1 , Makromolekulare Stoffe, G. Thieme Verlag Stuttgart 1961 , 411-420”.

[0093] The homogenization step ii) and iii) is usually carried out by applying mechanical agitation (rotor / stator disperser) or / and followed by using high force dispersion devices like for example an ultrasonic sound equipment (J. Dispersion Sci. Technology 2002, 23(1-3), 333- 349) or a high pressure homogenizer (APV Gaulin homogenizer; Microfluidizer). The emulsification / homogenization can be carried out continuously or batchwise. Apparatus for this purpose are known in the art. This is for example described in US5108654.

[0094] The polymerization step iv) is usually carried out by adding a free radical polymerization initiator.

[0095] Preferably the free radical initiator is present in an amount of from 0.01 weight-% to 20 weight-%, more preferably from 0.1 weight-% to 10 weight-% and most preferably from 0.2 weight-% to 5 weight-%, based on the monomer or monomer mixture.

[0096] The polymerization initiator may be added batchwise or continuously to the reaction mixture.

[0097] Preferably the free radical initiator of component ii) is a redox initiator system or a photoinitiator, especially a bis-azo compound, a peroxide or a hydroperoxide, especially a hydroperoxide.

[0098] Specific preferred radical sources are 2,2’-azobisisobutyronitrile, 2,2’-azobis(2-methyl- butyronitrile), 2,2’-azobis(2,4-dimethylvaleronitrile), 2,2’-azobis(4-methoxy-2,4-dimethylvale- ronitrile), 1 ,1’-azobis(1 -cyclohexanecarbonitrile), 2,2’-azobis(isobutyramide) dihydrate, 2- phenylazo-2,4-dimethyl-4-methoxyvaleronitrile, dimethyl-2,2’-azobisisobutyrate, 2- (carbamoylazo)isobutyronitrile, 2,2’-azobis(2,4,4-trimethylpentane), 2,2’-azobis(2- methylpropane), 2,2’-azobis(N,N’-dimethyleneisobutyramidine), free base or hydrochloride, 2,2’-azobis(2-amidinopropane), free base or hydrochloride, 2,2’-azobis{2-methyl-N-[1 ,1- bis(hydroxymethyl)ethyl]propionamide} or 2,2’-azobis{2-methyl-N-[1 ,1-bis(hydroxymethyl)-2- hydroxyethyl]propionamide; acetyl cyclohexane sulphonyl peroxide, diisopropyl peroxy dicarbonate, t-amyl perneodecanoate, t-butyl perneodecanoate, t-butyl perpivalate, t- amylperpivalate, bis(2,4-dichlorobenzoyl)peroxide, diisononanoyl peroxide, didecanoyl peroxide, dioctanoyl peroxide, dilauroyl peroxide, bis (2-methylbenzoyl) peroxide, disuccinic acid peroxide, diacetyl peroxide, dibenzoyl peroxide, t-butyl per 2-ethylhexanoate, bis-(4- chlorobenzoyl)-peroxide, t-butyl perisobutyrate, t-butyl permaleinate, 1 , 1 -bis(t- butylperoxy)3,5,5-trimethylcyclohexane, 1 ,1-bis(t-butylperoxy)cyclohexane, t-butyl peroxy isopropyl carbonate, t-butyl perisononaoate, 2,5-dimethylhexane 2,5-dibenzoate, t-butyl peracetate, t-amyl perbenzoate, t-butyl perbenzoate, 2,2-bis (t-butylperoxy) butane, 2,2 bis (t-butylperoxy) propane, dicumyl peroxide, 2,5-dimethylhexane-2,5-di-t-butylperoxide, 3-t- butylperoxy 3-phenylphthalide, di-t-amyl peroxide, a, a’-bis(t-butylperoxy isopropyl) benzene, 3,5-bis (t-butylperoxy)3,5-dimethyl 1 ,2-dioxolane, di-t-butyl peroxide, 2,5-dimethylhexyne-2,5- di-t-butylperoxide, 3,3,6,6,9,9-hexamethyl 1 ,2,4,5-tetraoxa cyclononane, p-menthane hydroperoxide, pinane hydroperoxide, diisopropylbenzene mono-a-hydroperoxide, cumene hydroperoxide or t-butyl hydroperoxide, particularly preferred is t-butyl hydroperoxide.

[0099] It is also possible to use combinations of Fe-compounds or Co-compounds with peroxo salts or salts of bisulfites or hydrosulfites. These combinations are known as redox systems. The polymerization temperature depends on the initiator used. Usually, the polymerization temperature is in the range of 5° C to 95° C and preferably from 30° C to 90°. If pressure is applied the temperature can raise up to 120° C, however, polymerization under normal pressure is the usual process.

[0100] Alternatively the polymerization can be initiated by photoinitiators and electromagnetic radiation, in particular actinic radiation.

[0101] Photoinitiators suitable for use in the process according to the invention are in principle any compounds and mixtures that form one or more free radicals when irradiated with electromagnetic waves. These include initiator systems consisting of a plurality of initiators and systems that function independently of one another or synergistically. In addition to coinitiators, for example amines, thiols, borates, enolates, phosphines, carboxylates and imidazoles, it is also possible to use sensitisers, for example acridines, xanthenes, thiazenes, coumarins, thioxanthones, triazines and dyes. A description of such compounds and initiator systems can be found e.g. in Crivello J.V., Dietliker K.K., (1999): Chemistry & Technology of UV & EB Formulation for Coatings, Inks & Paints, and in Bradley G. (ed.) Vol. 3: Photoinitiators for Free Radical and Cationic Polymerisation 2nd Edition, John Wiley & Son Ltd. The photoinitiator suitable for the process according to the invention in step b) may be either an initiator having an unsaturated group or an initiator not having such a group

[0102] Such compounds and derivatives are derived, for example, from the following classes of compounds: benzoins, benzil ketals, acetophenones, hydroxyalkylphenones, aminoalkylphenones, acylphosphine oxides, acylphosphine sulfides, acyloxyiminoketones, alkylaminosubstituted ketones, such as Michler's ketone, peroxy compounds, dinitrile compounds, halogenated acetophenones, phenylglyoxylates, dimeric phenylglyoxalates, benzophenones, oximes and oxime esters, thioxanthones, coumarins, ferrocenes, titanocenes, onium salts, sulfonium salts, iodonium salts, diazonium salts, borates, triazines, bisimidazoles, polysilanes and dyes. It is also possible to use combinations of the compounds from the mentioned classes of compounds with one another and combinations with corresponding coinitiator systems and / or sensitisers.

[0103] The polymerisation initiator can also be one of the group of thermally reacting water soluble or oil soluble initiators such as persulfates (e.g. ammonium or potassium salt thereof) or hydrochloride salts of diazo compounds such as 2,2’-azobis(2-(2-imidazolin-2-yl)propane) dihydrochloride, CAS 27776-21-2, for introduction into the water phase before or after the preparation of the miniemulsion. Oil soluble peroxides such as dilauroyl peroxide, dicetyl proxydicarbonate, tert-amyl peroxyneodecanoate, tert-amyl peroxypivalate and tert-butyl peroxy-2-ethylhexanoate, as well as AIBN are dissolved in the monomer phase prior to the preparation of the miniemulsion.

[0104] The final aqueous product form might be stabilized with a biocide against fungal, bacterial or algae growth, for instance, with biocidically active amount of commerically available products containing CIT, MIT, BIT, phenoxyethanol, 4-hydroxybenzoic alkyl esters (Nipagin), phenonip or combinations thereof.

[0105] Another aspect of the present invention is a composition stabilized against thermal, oxidative or light-induced degradation which comprises

[0106] (A) an organic material susceptible to thermal, oxidative or light induced degradation, and

[0107] (B) the concentrated aqueous polymer dispersion as defined herein.

[0108] For instance, the amount of component B) is from 0.1 to 40%, preferably 0.1 to 20%, more preferably 0.1 to 10%, most preferably 0.1 to 5%, by weight based on the weight of the component A) (i.e. organic material to be stabilised).

[0109] For instance, the organic material a) is a binder polymer selected from the group consisting of polyolefins, polyester and alkyd resin emulsions, polyvinylacetate, silicone resin emulsions, polyurethanes, acrylic emulsions and suspension PVC. Some examples of such binder polymers are aqueous poly(meth)acrylate dispersions, PUDs (polyurethane dispersions), polyesters, ethylene-vinylacetate dispersions, vinylacrylic dispersions, alkyd emulsions, styrene / acrylate dispersions, aq. solution polymers of before mentioned polymers, all kinds of physical & chemical mixtures of the binder polymers mentioned before; e.g. wb 2k PUR-acrylic dispersions including blocked polyisocyanates, acrylic melamine stoving enamels, especially preferred is polyacrylate.

[0110] For instance, the organic material is a recording material. Preferably, the recording material is a photographic material or an inkjet material. Preferably, the recording material is a printed material containing the concentrated aqueous polymer dispersion in an overprint varnish. The recording material can be such as described in W02005 / 023878, page 54, line 11 to page 58, line 20.

[0111] Adhesive polymers and adhesive compositions

[0112] The term “adhesive polymer”, as used herein, comprises preferably acrylic adhesive polymers and polyurethane adhesive polymers. The term “adhesive composition”, as used herein, comprises preferably aqueous dispersions of adhesive polymers. An aqueous dispersion of an adhesive polymer is a composition containing an adhesive polymer dispersed in water or in a predominantly aqueous medium with adhesive properties. The term (meth)acrylate and similar terms are used as an abbreviation for "acrylate or methacrylate". The terms “aqueous composition” and “aqueous polymer dispersion” refers to solvent systems primarily based on water, preferably containing no or less than 20%, less than 10%, less than 5%, less than 3% or less than 1% by weight of organic solvents (such as for example methanol, ethanol or tetrahydrofuran), based on the total composition. It is preferred not to use organic solvents. Reported quantities for monomers of an adhesive polymer are based, unless otherwise explicitly stated, on 100 parts by weight of the sum of all monomers. Preferred adhesive compositions are pressure-sensitive adhesive compositions and lamination adhesive compositions. A pressure-sensitive adhesive (PSA) is a viscoelastic adhesive whose set film at room temperature (20 °C) in the dry state remains permanently tacky and adhesive (self-adhesive). Bonding to substrates is accomplished instantaneously by gentle applied pressure. The loop tack of a dried film of the pressure-sensitive adhesive preferably is more than 1 .7 N / 25 mm, at least 2 N / 25 mm, more preferred at least 2.5 N / 25 mm or at least 3 N / 25 mm (adhesive applied at an application thickness of 20 pm on a 12 pm thick polyester film, measured on steel at room temperature (20 °C) at a peeling speed of 300 mm / min).

[0113] A lamination adhesive composition is an adhesive suitable for use in lamination processes, the lamination adhesive is preferably non-self-adhesive. Non-self-adhesive adhesives are adhesives that, unlike pressure-sensitive adhesives, have little or no stickiness at room temperature and are preferably applied with pressure and / or elevated temperature. The stickiness measured as a loop tack is preferably less than 1 .7 N / 25 mm (adhesive with an application thickness of 20 pm applied to a 12 pm thick polyester film, measured on steel at room temperature (20 °C) with a removal speed of 300 mm / min).

[0114] A pressure-sensitive adhesive polymer is a polymer with a glass transition temperature preferably in the range of -60 °C and -20 °C, preferably from -50 to -25 °C. A lamination adhesive polymer is a polymer with a glass transition temperature of -40 °C to +15 °C, preferably of -10 °C to +10 °C. A lamination adhesive polymer is a polymer with a glass transition temperature preferably in the range of -45 °C to +15 °C, more particularly from -35 °C to +10 °C or from -10 to +10 °C. By a controlled variation of the nature and amount of the monomers it is possible for the skilled person to prepare adhesive polymer compositions whose polymers have a glass transition temperature within the desired range. The glass transition temperature is determined by differential scanning calorimetry (ASTM D 3418-08, midpoint temperature). The glass transition temperature of the polymer is the glass transition temperature obtained on evaluation of the second heating curve (heating rate 20 °C / min).

[0115] Aqueous adhesive acrylic polymer dispersions

[0116] The acrylic adhesive polymers are obtainable by radical polymerization of ethylenically unsaturated compounds (monomers), preferably by radical emulsion polymerization.

[0117] The adhesive polymer consists preferably to an extent of at least 40% by weight or at least 60% by weight, or at least 80% by weight, more preferably at least 90% by weight, of what are called principal monomers. The principal monomers are preferably selected from C1-C20 alkyl (meth)acrylates, vinyl esters of carboxylic acids comprising up to 20 C atoms, vinylaromatics having up to 20 C atoms, ethylenically unsaturated nitriles, vinyl halides, vinyl ethers of alcohols comprising 1 to 10 C atoms, aliphatic hydrocarbons having 2 to 8 C atoms and one or two double bonds, or mixtures of these monomers.

[0118] Preferred adhesive polymers are (meth)acrylate polymers. The (meth)acrylate polymers are formed from at least one (meth)acrylate monomer, which may be copolymerized with further monomers. Suitable monomers are, for example, (meth) acrylic acid alkyl esters having a Ci- Cio alkyl radical, such as methyl methacrylate, methyl acrylate, n-butyl acrylate, ethyl acrylate, and 2-ethylhexyl acrylate. In particular, mixtures of the (meth)acrylic acid alkyl esters are also suitable. Vinyl esters of carboxylic acids having 1 to 20 C atoms are, for example, vinyl laurate, vinyl stearate, vinyl propionate, Versatic acid vinyl esters, and vinyl acetate. Vinylaromatic compounds contemplated include vinyltoluene, a- and p- methylstyrene, a-butylstyrene, 4-n-butylstyrene, 4-n-decylstyrene, and - preferably - styrene. Examples of nitriles are acrylonitrile and methacrylonitrile. The vinyl halides are chlorine-, fluorine- or bromine-substituted, ethylenically unsaturated compounds, preferably vinyl chloride and vinylidene chloride. Examples of vinyl ethers include vinyl methyl ether and vinyl isobutyl ether. Preferred vinyl ethers are those of alcohols comprising 1 to 4 C atoms.

[0119] Suitable hydrocarbons having 4 to 8 C atoms and two olefinic double bonds are, for example, butadiene, isoprene, and chloroprene. Hydrocarbons having 2 to 4 C atoms are, for example, ethylene, propylene or butene. Preferred principal monomers are Ci to Cio alkyl acrylates and Ci to Cio alkyl methacrylates, more particularly Ci to C8alkylacrylates and methacrylates, and vinylaromatics, more particularly styrene, and mixtures thereof.

[0120] Especially preferred are methyl acrylate, methyl methacrylate, ethyl acrylate, n-butyl acrylate, n-hexyl acrylate, octyl acrylate, and 2-ethylhexyl acrylate, styrene, and also mixtures of these monomers.

[0121] As well as the principal monomers, the adhesive polymer preferably comprises further monomers, examples being acid monomers, monomers containing hydroxyl groups, more particularly Ci-Ci0-hydroxyalkyl (meth)acrylates, or (meth)acrylamide. Further monomers also include phenyloxyethylglycol mono(meth)acrylate, glycidyl (meth)acrylate, aminoalkyl (meth)acrylates such as, for example, 2-aminoethyl (meth)acrylate. Alkyl groups have preferably from 1 to 20 C atoms. Other further monomers include crosslinking monomers. The further monomers are used generally in minor amounts; their fraction in total is preferably below 10% by weight, more particularly below 5% by weight.

[0122] Preferred adhesive polymers of the adhesive composition are (meth)acrylate polymers which are formed not only of (meth)acrylic ester monomers but also of monomers having acid groups. The monomers having acid groups are present preferably at not less than 0.1% by weight, e.g. 0.1% to 15% by weight, preferably in amounts of 0.1% to 5%, more preferably 0.2% to 4%, very preferably 0.5% to 3% by weight, based on the total amount of monomers. Examples of monomers having acid groups are monomers having carboxylic, sulfonic or phosphonic acid groups. Carboxylic acid groups are preferred. Examples include acrylic acid, methacrylic acid, itaconic acid, maleic acid or fumaric acid. The acid groups may be present in the form of their salts.

[0123] Preferred adhesive polymers of the adhesive composition are made by emulsion polymerization of

[0124] (a) from 70 to 99.5 wt.% of acrylic acid alkyl ester monomers with 2 to 12 carbon atoms in the alkyl group; (b) at least from 0.4 wt.%, preferably more than 1 and preferably up to 10 wt.% of at least one ethylenically unsaturated, copolymerizable monomer having at least one acid group;

[0125] (c) optionally one or more monomers selected from methyl acrylate, methyl methacrylate and methacrylic acid alkyl ester monomers with 2 to 12 carbon atoms in the alkyl group;

[0126] (d) optionally one or more ethylenically unsaturated monomers different from monomers (a), (b) and (c); wt.% amounts of the monomers are based on the total weight amount of all monomers.

[0127] Monomers (a)

[0128] The monomer mixture for making the adhesive polymer preferably comprises from 70 to 99.5 wt.%, preferably from 75 to 99.5 wt.%, from 80 to 99.5 wt.% or from 91 to 99.5 wt.%, based on the total amount of monomers, of acrylic acid alkyl ester monomers (a) with 2 to 12 carbon atoms in the alkyl group. Preferred monomers (a) are acrylic acid alkyl esters with 2 to 8 carbon atoms in the alkyl group. Preferred monomers (a) are ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, tert-butyl acrylate, cyclohexyl acrylate, n-hexyl acrylate, n-octyl acrylate, 2-octyl acrylate, isooctyl acrylate, 2- propylheptyl acrylate and mixtures thereof. More preferred monomers (a) are one or more selected from ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, 2-octyl acrylate and isooctyl acrylate. Particularly preferred are one or more of ethyl acrylate, n-butyl acrylate, isobutyl acrylate and 2-ethylhexyl acrylate.

[0129] Monomers (b)

[0130] The monomer mixture for making the adhesive polymer comprises at least 0.4 wt.%, preferably more than 1 and preferably up to 10 wt.%, from more than 1 and up to less than 5 wt.% or from more than 1 and up to 4.5 wt.%, based on the total amount of monomers, of at least one ethylenically unsaturated, copolymerizable monomer having at least one acid group (acid monomer). The acid monomers (b) comprise monomers which contain at least one acid group, and also their anhydrides and salts thereof. The monomers (b) include alpha, beta-monoethylenically unsaturated monocarboxylic and dicarboxylic acids, monoesters of alpha, beta-monoethylenically unsaturated dicarboxylic acids, the anhydrides of the aforesaid alpha, beta-monoethylenically unsaturated carboxylic acids, and also ethylenically unsaturated sulfonic acids and their water-soluble salts, as for example their alkali metal salts. Examples thereof are acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, vinylacetic acid, and vinyllactic acid. Examples of suitable ethylenically unsaturated sulfonic acids include vinylsulfonic acid, styrenesulfonic acid, acrylamidomethylpropane sulfonic acid, sulfopropyl acrylate and sulfopropyl methacrylate. Preferred monomers (b) are alpha, beta-monoethylenically unsaturated carboxylic acids with 3 to 8 carbon atoms and dicarboxylic acids with 4 to 8 carbon atoms, e.g., acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, vinylacetic acid, vinyllactic acid, vinylsulfonic acid, styrenesulfonic acid, acrylamidoglycolic acid, acrylamidomethyl propane sulfonic acid, sulfopropyl acrylate, sulfopropyl methacrylate, their respective anhydrides and mixtures of these monomers. Particularly preferred monomers (b) are itaconic acid, acrylic acid and methacrylic acid.

[0131] Monomers (c)

[0132] The monomer mixture for making the adhesive polymer optionally comprises one or more monomers selected from methyl acrylate, methyl methacrylate and methacrylic acid alkyl ester monomers with 2 to 12 carbon atoms in the alkyl group. The amount of monomers (c) is for example from 0 to 20 wt.%, based on the total amount of monomers. Preferably, the monomer mixture comprises no monomer (c) or the amount of monomers (c) is less than 10 wt.%, less than 5 wt.% or less than 1 wt.% of monomers (c). Monomers (c) are for example methyl methacrylate, methyl acrylate, ethyl methacrylate, propyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate and iso-decyl methacrylate. In particular, mixtures of the alkyl (meth)acrylates are also suitable. If present, preferred monomers (c) are methyl acrylate, methyl methacrylate or a mixture thereof.

[0133] Monomers (d)

[0134] The monomer mixture for making the adhesive polymer optionally comprises one or more monomers selected from ethylenically unsaturated monomers different from monomers (a), (b) and (c). The amount of monomers (d) is for example from 0 to 20 wt.%, based on the total amount of monomers. Preferably, the monomer mixture comprises no monomer (d) or the amount of monomers (d) is from 0.1 to 10 wt.%, from 0.1 to 5 wt.% or from 0.2 to 1 wt.%. Monomers (d) are for example selected from hydroxyalkyl (meth)acrylates having from 1 to 10 C atoms, preferably from 1 to 4 C atoms in the hydroxyalkyl group, vinyl esters of carboxylic acids comprising up to 20 C atoms, vinylaromatics having up to 20 C atoms, ethylenically unsaturated nitriles, amides of ethylenically unsaturated carboxylic acids (preferably acrylamide or methacrylamide), N-alkylolamides of ethylenically unsaturated carboxylic acids (preferably N-methylol acrylamide and N-methylol methacrylamide), phenyloxyethyl glycol mono(meth)acrylates, vinyl halides, vinyl ethers of alcohols comprising 1 to 10 C atoms, aliphatic hydrocarbons having 2 to 8 carbon atoms and one or two double bonds, ethylenically unsaturated monomers containing amino groups, bifunctional monomers which as well as an ethylenically unsaturated double bond have at least one glycidyl group (preferably glycidyl acrylate or glycidyl methacrylate), oxazoline group, ureido group, ureido- analogous group or carbonyl group, preferably diacetone acrylamide, and crosslinking monomers which have more than one free-radically polymerizable ethylenically unsaturated group, or mixtures of these monomers.

[0135] Hydroxyalkyl (meth)acrylates having from 1 to 10 C atoms in the alkyl group are for example hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate and 4-hydroxybutyl acrylate. Vinyl esters of carboxylic acids having 1 to 20 carbons are, for example, vinyl laurate, vinyl stearate, vinyl propionate, Versatic acid vinyl esters, and vinyl acetate. Useful vinylaromatic compounds include vinyltoluene, alpha- and para-methylstyrene, alpha-butylstyrene, 4-n-butylstyrene, 4-n-decylstyrene and, preferably, styrene. Monomers containing amino groups are for example the aminoalkyl esters of the aforesaid alpha, beta-monoethylenically unsaturated carboxylic acids, preferably C1-C10 aminoalkyl (meth)acrylates such as, for example, 2-aminoethyl (meth)acrylate or tert-butyl- aminoethyl methacrylate. Examples of nitriles are the nitriles of alpha, beta-monoethylenically unsaturated C3-C8 carboxylic acids, preferably acrylonitrile and methacrylonitrile. The vinyl halides are ethylenically unsaturated compounds substituted by chlorine, fluorine or bromine, preferably vinyl chloride and vinylidene chloride. Examples of vinyl ethers which may be mentioned are vinyl methyl ether or vinyl isobutyl ether. Preference is given to vinyl ethers of alcohols comprising 1 to 4 carbons. Hydrocarbons having 4 to 8 carbons and two olefinic double bonds include butadiene, isoprene and chloroprene. Monomers with an ureido group are monomers having a substituent of formula where X is NH or NR and R is an organic group such as for example alkyl, preferably alkyl with 1 to 4 C-atoms. The arrow at the N-atoms indicates the connection to the remaining part of the monomer, preferably a (meth)acrylate monomer. Monomers with an ureido-analogous groups are monomers having a substituent of the above formula where X is O or CH2. Preferred is ureido alkyl(meth)acrylate with 1 to 10 C-atoms, preferably 2 to 4 C-atoms in the alkyl group, In particular ureido ethyl methacrylat (UMA).

[0136] A preferred aqueous adhesive composition comprises an adhesive polymer made by emulsion polymerization, wherein the monomers (a) are used in an amount of 80 to 99.5 wt.%, preferably from 91 to 99.5 wt.%, based on the total amount of monomers and are one or more selected from ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, 2- ethylhexyl acrylate, n-octyl acrylate, 2-octyl acrylate and isooctyl acrylate; the monomers (b) having at least one acid group are used in an amount of more than 1 and up to 4.5 wt.%, based on the total amount of monomers, and are one or more selected from acrylic acid, methacrylic acid, itaconic acid and acrylamidomethylpropane sulfonic acid; monomers (c) are used in amounts of from 0 to 15 wt.%, based on the total amount of monomers, and are methyl acrylate, methyl methacrylate or a mixture thereof; and the monomers (d) are used in an amount of 0 to 10 wt.%, based on the total amount of the monomers, and are one or more selected from acrylamide, and hydroxyalkyl (meth)acrylates having from 1 to 4 C atoms in the alkyl group.

[0137] Emulsion polymerization

[0138] The emulsion polymerization is carried out in an aqueous medium. This can for example be fully deionized water or else mixtures of water and a solvent miscible therewith such as methanol, ethanol, ethylene glycol, glycerol, sugar alcohols such as sorbitol or tetra hydrofuran. The total amount of aqueous medium is proportioned here such that the aqueous polymer dispersion obtained has a solids content of 20% to 70% by weight, frequently 30% to 65% by weight and often 40% to 60% by weight.

[0139] The polymerization can be carried out under acidic, neutral or alkaline conditions. The pH values has an influence on colloidal stability of the dispersion and can be controlled by the addtion of bases. Also, alkaline pH is favorable if alkaline soluble resins are used as stabilizer (protective colloid).

[0140] The polymerisation process uses free-radical initiators (also referred to as free-radical polymerization initiators), that is to say initiators which form free radicals under the reaction conditions. These may be peroxides or they may be azo compounds. Redox initiator systems are of course also suitable.

[0141] Peroxides used may in principle be inorganic peroxides and / or organic peroxides. Examples of suitable inorganic peroxides include hydrogen peroxide and peroxodisulfates, such as the mono- or dialkali metal or ammonium salts of peroxodisulfuric acid, for example the mono- and disodium, mono- and dipotassium, or ammonium salts thereof. Examples of suitable organic peroxides are alkyl hydroperoxides such as tert-butyl hydroperoxide, and amyl or isoamyl hydroperoxide, aryl hydroperoxides such as p-menthyl or cumene hydroperoxide, and dialkyl or diaryl peroxides such as di-tert-butyl, dibenzoyl or dicumene peroxide.

[0142] Azo compounds used are essentially 2, 2'-azobis(isobutyronitrile), 2,2'-azobis(2- methylbutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(N,N'-dimethylene isobutyroamidine) dihydrochloride, 4,4'-Azobis(4-cyanovaleric acid) (corresponding to V501 from Wako Chemicals) and 2,2'-azobis(amidinopropyl) dihydrochloride (AIBA, corresponding to V-50 from Wako Chemicals).

[0143] Redox initiator systems are combined systems made up of at least one organic or inorganic reducing agent and at least one peroxide. Suitable oxidants for redox initiator systems are essentially the peroxides mentioned above. Corresponding reducing agents that may be used are sulfur compounds in a low oxidation state such as alkali metal sulfites, for example potassium and / or sodium sulfite, alkali metal hydrogen sulfites, for example potassium and / or sodium hydrogen sulfite, alkali metal metabisulfites, for example potassium and / or sodium metabisulfite, acetone bisulfite, formaldehyde sulfoxylates, for example potassium and / or sodium formaldehyde sulfoxylate, alkali metal salts, specifically potassium and / or sodium salts of aliphatic sulfinic acids and alkali metal hydrogen sulfides, for example potassium and / or sodium hydrogen sulfide, salts of polyvalent metals, such as iron(ll) sulfate, iron(ll) ammonium sulfate, iron(ll) phosphate, enediols, such as dihydroxymaleic acid, benzoin and / or ascorbic acid, or isoascorbic acid as well as their salts, and reducing saccharides, such as sorbose, glucose, fructose and / or dihydroxyacetone.

[0144] Preferred free-radical initiators are inorganic and organic peroxides, preferably ammonium or alkali metal salts of peroxosulfates or peroxodisulfates, and tert-butyl, p-menthyl and cumyl hydroperoxide, in particular selected from ammonium, sodium and potassium peroxodisulfate, tert-butyl hydroperoxide and cumyl hydroperoxide. Particular preference is given here to using both at least one inorganic peroxide, preferably peroxodisulfate, in particular ammonium or sodium peroxodisulfate, and / or one organic peroxide, preferably alkyl hydroperoxide, in particular t-butyl hydroperoxide. The polymerization is generally carried out using 0.1 to 5 parts by weight of the free-radical initiator, preferably 0.5 to 4 parts by weight of the free-radical initiator, based on 100 parts by weight of total monomers.

[0145] Initiation of the polymerization reaction is understood to mean the start of the polymerization reaction of the monomers present in the polymerization vessel as a result of decomposition of the free-radical initiator.

[0146] Preferably the process is a monomer feed process. A monomer feed process means that the major amount, typically at least 90%, preferably at least 93%, of the monomers to be polymerized is supplied to the polymerization reaction under polymerization conditions.

[0147] It is possible here to include a portion of the monomers in an initial charge in the polymerization vessel before the beginning of the polymerization. According to this preferred variant, then, the polymerization may be initiated in an initial charge which contains 1 to 10 parts by weight of the total monomers and then monomers and emulsifier are metered continuously. More particularly it is possible to include up to 5% of the respective monomer in an initial charge and then to initiate the polymerization.

[0148] Polymerization conditions mean, generally, those amounts of radical initiator and those temperatures and pressures under which the radically initiated aqueous emulsion polymerization does not come to a standstill. The polymerization here is dependent primarily on the nature and amount of the radical initiator used. The relationships between temperature and decomposition rate are well known to the skilled person for the common polymerization initiators or can be ascertained in routine experiments.

[0149] According to a preferred embodiment, the monomers and the emulsifier are metered continuously. In other words, the monomer metering and also the emulsifier metering take place in a continuous mass flow, i.e., without interruption.

[0150] The polymerization is carried out in a temperature range of 70 to 95 °C, preferably >75 °C to < 90 °C.

[0151] The metering of the conjugated aliphatic diene is generally carried out at elevated pressure. The metering of the conjugated aliphatic diene preferably takes place at a pressure in the range from 5 to 15 bar. The elevated pressure has the effect that for example the 1 ,3- butadiene which is gaseous at standard pressure and room temperature largely resides in the polymerization mixture.

[0152] The monomers are preferably metered in continuously, that is say without interruption. In this case, the monomers are preferably metered in with a metering rate which deviates from the average value of the respective overall feed by no more than 30%, preferably by no more than 20%. According to a preferred embodiment, the metering rate of the monomers (increase in the monomers) corresponds approximately to the polymerization rate of the monomers (decrease in the monomers).

[0153] In order to promote the emulsification of the monomers in the aqueous medium, it is possible to use the typically used protective colloids and / or emulsifiers. An extensive description of suitable protective colloids can be found in Houben-Weyl, Methoden der organischen Chemie [Methods of Organic Chemistry], volume XIV / 1 , Makromolekulare Stoffe [Macromolecular Materials], Georg-Thieme-Verlag, Stuttgart, 1961 , pages 411 to 420, which is hereby incorporated by reference.

[0154] The use of alkaline soluble resins as protective colloids is for example described in EP 3487 895 and literature cited therein.

[0155] Useful emulsifiers include interface-active substances having a number-average molecular weight of typically below 2000 g / mol or preferably below 1500 g / mol, whereas the numberaverage molecular weight of the protective colloids is above 2000 g / mol, for example from 2000 to 100 000 g / mol, in particular from 5000 to 50 000 g / mol. Suitable emulsifiers are described in WO 2020 / 114798 on pages 9, line 40 to page 10, line 22.

[0156] If emulsifiers and / or protective colloids are additionally used as auxiliaries for dispersing the monomers, the amounts used thereof are for example 0.1 to 5 parts by weight based on 100 parts by weight of monomers.

[0157] Commonly used emulsifiers are, for example, ethoxylated mono-, di- and trialkylphenols (EO level: 3 to 50, alkyl radical: C4to C12), ethoxylated fatty alcohols (EO level: 3 to 50; alkyl radical: C8to C36) and alkali metal and ammonium salts of alkyl sulfates (alkyl radical: C8to C12), of sulfuric monoesters of ethoxylated alkanols (EO level: 3 to 30, alkyl radical: C12 to Ci8) and ethoxylated alkylphenols (EO level: 3 to 50, alkyl radical: C4to C12), of alkylsulfonic acids (alkyl radical: C12 to Ci8) and of alkylarylsulfonic acids (alkyl radical: C9to Ci8). Further suitable emulsifiers can be found in Houben-Weyl, Methoden der organischen Chemie [Methods of Organic Chemistry], vol. XIV / 1 , Makromolekulare Stoffe [Macromolecular substances], pages 192-208, Georg-Thieme-Verlag, Stuttgart, 1961.

[0158] If dispersing aids are included in the preparation of the aqueous dispersion of the polymer P, the total amount of dispersing aids used, especially emulsifiers, is 0.1% to 5% by weight, preferably 1% to 3% by weight, based in each case on the total amount of the monomers. In an advantageous embodiment, emulsifiers are used as the sole dispersing aids.

[0159] If dispersing aids are included in the preparation of the aqueous dispersion of the polymer P, it is optionally possible to initially charge a portion or the entirety of the dispersing aids as a constituent of the aqueous medium comprising the polymer A. Alternatively, it is possible to meter in the entirety or any remaining residual amount of dispersing aids together with the monomers P during the polymerization reaction. The manner in which the entirety or any remaining residual amount of dispersing aids is metered into the aqueous polymerization medium here can be discontinuous in one or more portions, or continuous with constant or varying flow rates.

[0160] According to one embodiment, the polymerization is conducted in the presence of a degraded starch. Preference is given in the emulsion copolymerization to using 15 to 100 parts by weight of a degraded starch per 100 parts by weight of the monomers. Degraded starches are generally known and described, for example, in W02020 / 249406 on pages 15 to page 16, line 2. Preference is given to degraded native starches, in particular native starches degraded to maltodextrin. Preference is given to degraded starches with an intrinsic viscosity qi of <0.07 dl / g or preferably <0.05 dl / g. The intrinsic viscosity qi of the degraded starches is preferably in the range of 0.02 to 0.06 dl I g. The intrinsic viscosity qi is determined according to DIN EN1628 at a temperature of 23 °C.

[0161] According to a further preferred embodiment, no degraded starch is present during polymerization.

[0162] As well as the seed-free mode of preparation, the polymer particle size can also be adjusted by effecting the emulsion polymerization for preparation of the polymers P by the seed latex process or in the presence of a seed latex produced in situ. Such processes are known to those skilled in the art and can be found in the prior art (see e.g. EP-B 40 419, EP-A 567 812, EP-A 614 922 and “Encyclopedia of Polymer Science and Technology”, vol. 5, page 847, John Wiley & Sons Inc., New York, 1966).

[0163] According to one preferred variant of the emulsion polymerization process, a seed latex is employed. By a seed latex, the skilled person usually understands a polymer dispersion whose seed particles act as core of particle formation in the polymerization process.

[0164] In order to modify the properties of the polymers, it is possible to conduct the emulsion polymerization optionally in the presence of at least one free-radical chain transfer agent, particular preference being given to sulfur-, nitrogen- and / or phosphorus-containing free- radical chain transfer agents having a solubility of > 5 g / 100 g of water in deionized water at 20°C and 1 atm. These are typically used to reduce or to control the molecular weight of the polymers obtainable by a free-radical aqueous emulsion polymerization.

[0165] Sulfur-containing free-radical chain transfer agents used are, for example, alkyl mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, t-octyl mercaptan, n-dodecyl mercaptan, t- dodecyl mercaptan and n-stearyl mercaptan, mercaptoalkanols such as 2-mercaptoethanol, 2-mercaptopropanol or 3-mercaptopropanol, alkyl ester of thioglycolic acid such as 2- ethylhexyl thioglycolate, alkyl ester of 3-mercaptopropionic acid such as isooctyl mercaptopropionate, alkali metal hydrogensulfites such as sodium hydrogensulfite or potassium hydrogensulfite, and thiosulfuric acid and the alkali metal salts thereof or 3- mercapto-2-aminopropanoic acid (cysteine), nitrogen-containing free-radical chain transfer agents used are, for example, hydroxylamine (ammonium) compounds such as hydroxylammonium sulfate, and phosphorus-containing free-radical chain transfer agents used are, for example, phosphorous acid, hypophosphorous acid, metaphosphorous acid, orthophosphoric acid, pyrophosphoric acid or polyphosphoric acid and the alkali metal salts thereof, especially the sodium or potassium salts thereof, advantageously sodium hypophosphite or sodium dihydrogenphosphate, and thiuram-based compounds such as terpinolen.

[0166] Especially advantageously, the free-radical chain transfer agent is selected from hypophosphorous acid and the alkali metal salts thereof, especially sodium hypophosphite, alkali metal hydrogensulfites, especially sodium hydrogensulfite, hydroxylammonium sulfate and / or 2-mercaptoethanol, t-dodecyl mercaptan and terpinolen.

[0167] According a preferred embodiment the free-radical chain transfer agent used in the polymerization is in an amount < 1 parts by weight, preferably in the range of from 0.1 to 1 , preferably in the range of from 0.2 to 0.8 parts by weight, based on 100 parts by weight of total monomers used in the polymerization.

[0168] The free-radical aqueous emulsion polymerization can be carried out as a free radical aqueous multistep emulsion polymerization. A free-radical aqueous multistep emulsion polymerization is a free-radical aqueous emulsion polymerization, which is carried out in at least two successive polymerization steps, where in each step a portion M’ of the monomers M is polymerized in a free-radical emulsion polymerization, where the second and any further polymerization step is carried out in the polymer dispersion obtained in the previous step.

[0169] Aqueous adhesive polyurethane dispersions

[0170] The polyurethane adhesive polymers are obtainable by polycondensation of polyisocyanates and polyols. Suitable polyurethane dispersions are in principle obtainable by reaction of at least one polyisocyanate with at least one compound having at least two isocyanate-reactive groups and dispersion in water. Suitable polyurethanes also include so-called polyurethanepolyureas comprising not only polyurethane groups but also urea groups. The polyurethane dispersion preferably comprises at least one polyurethane which comprises at least one polyisocyanate and at least one polymeric polyol in copolymerized form. The polyurethane may in particular 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 polyol preferably has a number-average molecular weight in the range from about 500 to 5000 g / mol. Polymeric diols are preferred. The polyurethane dispersion preferably comprises at least one polyurethane which comprises at least one polyisocyanate and a diol component in copolymerized form, of which a) 10-100 mol% based on the total amount of the diols have a molecular weight of 500 to 5000 g / mol and b) 0-90 mol% based on the total amount of the diols have a molecular weight of 60 to 500 g / mol. The polyurethane is preferably constructed to an extent of at least 40% by weight, particularly preferably to an extent of at least 60% by weight and very particularly preferably to an extent of at least 80% by weight, based on the total weight of the monomers used for producing the polyurethane, from at least one diisocyanate and at least one polyether diol and / or polyester diol. Suitable further synthesis components to 100% by weight include for example the polyisocyanates recited below having at least three NCO groups and compounds distinct from the polymeric polyols having at least two isocyanate-reactive groups. These include for example diols; diamines; polymers distinct from polymeric polyols having at least two active hydrogen atoms per molecule; compounds having two active hydrogen atoms and at least one ionogenic / ionic group per molecule; and mixtures thereof. The polyurethane preferably has a softening point or melting point in the range from -50°C to 150°C, particularly preferably from 0°C to 100°C and very particularly preferably from 10°C to 90°C.

[0171] Preferred polyurethanes are constructed from: a) at least one monomeric diisocyanate, b) at least one diol, wherein the component (b) comprises at least one diol having a number-average molecular weight in the range from 500 to 5000 g / mol, c) at least one monomer distinct from the monomers (a) and (b) having at least one isocyanate group or at least one isocyanate-reactive group which further bears at least one hydrophilic group or a potentially hydrophilic group, d) optionally at least one further compound distinct from the monomers (a) to (c) having at least two reactive groups selected from alcoholic hydroxyl groups, primary or secondary amino groups or isocyanate groups, and e) optionally at least one monofunctional compound distinct from the monomers (a) to (d) having a reactive group which is an alcoholic hydroxyl group, a primary or secondary amino group or an isocyanate group.

[0172] The component b) is preferably composed of bi> 10 to 100 mol%, based on the total amount of component b), of diols having a molecular weight of 500 to 5000 g / mol, b2; 0 to 90 mol%, based on the total amount of component b), of diols having a molecular weight of 60 to less than 500 g / mol.

[0173] It is particularly preferable when the ratio of the diols bi) to the monomers b2) is 0.1 : 1 to 5: 1 , particularly preferably 0.2:1 to 2:1 . The diol b) is in particular selected from polytetrahydrofuran, polypropylene oxide and polyesterdiols selected from reaction products of dihydric alcohols with dibasic carboxylic acids and lactone-based polyesterdiols. Compounds suitable as monomers (a) include in particular diisocyanates X(NCO)2, wherein X is an acyclic aliphatic hydrocarbon radical having 4 to 15 carbon atoms, a cycloaliphatic or aromatic hydrocarbon radical having 6 to 15 carbon atoms or an araliphatic hydrocarbon radical having 7 to 15 carbon atoms. Examples of such diisocyanates are tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1 ,4- diisocyanatocyclohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (IPDI), 2,2-bis(4-isocyanatocyclohexyl)-propane, trimethylhexane diisocyanate, 1 ,4- diisocyanatobenzene, 2,4-diisocyanato-toluene, 2,6-diisocyanatotoluene, 4,4’- diisocyanatodiphenylmethane, 2,4’-diisocyanatodiphenylmethane, p-xylylene diisocyanate, tetramethylxylylene diisocyanate (TMXDI), the isomers of bis(4- isocyanatocyclohexyl)methane (HMDI), such as the trans / trans, the cis / cis and the cis / trans isomers, and mixtures composed of these compounds.

[0174] Such diisocyanates are commercially available. Mixtures of these isocyanates of particular importance are the mixtures of the respective structural isomers of diisocyanatotoluene and diisocyanatodiphenylmethane, the mixture of 80 mol% of 2,4-diisocyanatotoluene and 20 mol% of 2,6-diisocyanatotoluene being particularly suitable and preferred. In addition, the mixtures of aromatic isocyanates such as 2,4-diisocyanatotoluene and / or 2,6- diisocyanatotoluene with aliphatic or cycloaliphatic isocyanates, such as hexamethylene diisocyanate or IPDI, are particularly advantageous, the preferred quantitative ratio of the aliphatic isocyanates to aromatic isocyanates being 1 :9 to 9:1 , in particular 4:1 to 1 :4. The diols (b1) may be polyester polyols and these are known for example from Ullmann's Encyclopedia of Industrial Chemistry, 4th edition, volume 19, pp. 62 to 65. Preference is given to using polyester polyols obtained by reaction of dihydric alcohols with dibasic carboxylic acids. Instead of using the free polycarboxylic acids, the polyester polyols may also be produced using the corresponding polycarboxylic anhydrides or corresponding polycarboxylic esters of lower alcohols or mixtures thereof. The polycarboxylic acids may be aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic and may optionally be substituted, for example by halogen atoms, and / or unsaturated. Examples thereof include: suberic acid, azelaic acid, phthalic acid, isophthalic acid, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrachlorophthalic anhydride, endomethylene tetrahydrophthalic anhydride, glutaric anhydride, maleic acid, maleic anhydride, fumaric acid, dimeric fatty acids. Preference is given to dicarboxylic acids of the general formula HOOC-(CH2)y-COOH, wherein y is a number from 1 to 20, preferably an even number from 2 to 20, for example succinic acid, adipic acid, sebacic acid and dodecanedicarboxylic acid. Suitable dihydric alcohols are, for example, ethylene glycol, propane-1 , 2-diol, propane-1 , 3-diol, butane-1 ,3-diol, butene-1 ,4-diol, butyne-1 ,4-diol, pentane-1 ,5-diol, neopentyl glycol, bis(hydroxymethyl)cyclohexanes such as 1 ,4- bis(hydroxymethyl)cyclohexane, 2-methylpropane-1 , 3-diol, methylpentanediols, furthermore diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, dibutylene glycol and polybutylene glycols. Preferred alcohols are those of the general formula HO-(CH2)X-OH, wherein x is a number from 1 to 20, preferably an even number from 2 to 20. Examples thereof are ethylene glycol, butane-1 ,4- diol, hexane-1 ,6-diol, octane-1 , 8-diol and dodecane-1 ,12-diol. Neopentyl glycol is also preferred.

[0175] The diols (b1) may also be polycarbonate diols such as are obtainable for example by reaction of phosgene with an excess of the low molecular weight alcohols recited as synthesis components for the polyester polyols. The diols (b1) may also be lactone-based polyester diols, specifically homopolymers or copolymers of lactones, preferably terminal hydroxyl-comprising addition products of lactones onto suitable difunctional starter molecules. Contemplated lactones preferably include those derived from compounds of the general formula HO-(CH2)Z-COOH, wherein z is a number from 1 to 20 and one hydrogen atom of a methylene unit may also be substituted by a Ci- to C4-alkyl radical. Examples include epsilon-caprolactone, beta-propiolactone, gamma-butyrolactone and / or methyl- gamma-caprolactone and mixtures thereof. Suitable starter components are, for example, the low-molecular weight-dihydric alcohols recited hereinabove as synthesis components for the polyester polyols. The corresponding polymers of epsilon-caprolactone are particularly preferred. Lower polyester diols or polyether diols may also be employed as starters for producing the lactone polymers. Instead of the polymers of lactones, the corresponding, chemically equivalent polycondensates of the hydroxycarboxylic acids corresponding to the lactones may also be employed.

[0176] The diols (b1) may also be polyether diols. Polyether diols are obtainable in particular by homopolymerization of ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, styrene oxide or epichlorohydrin, for example in the presence of BF3, or by addition of these compounds optionally in admixture or in succession onto starting components having reactive hydrogen atoms, such as alcohols or amines, for example water, ethylene glycol, propane-1 , 2-diol, propane-1 , 3-diol, 2,2-bis(4-hydroxyphenyl)propane or aniline. Polyether diols having a molecular weight of 500 to 5000 and especially 600 to 4500 are particularly preferred. Particularly preferred polyether diols are polypropylene oxide and polytetrahydrofuran. Suitable polytetrahydrofurans may be produced by cationic polymerization of tetrahydrofuran in the presence of acidic catalysts, such as for example sulfuric acid or fluorosulfuric acid. Such methods of production are known to those skilled in the art. Suitable compounds b1) further include alpha, omega-diaminopolyethers producible by amination of polyalkylene oxides with ammonia. bi) only includes polyether diols formed to an extent of less than 20% by weight, based on their total weight, of ethylene oxide. Polyether diols comprising at least 20% by weight of incorporated ethylene oxide units are hydrophilic polyether diols that are included among the monomers c).

[0177] Optionally co-usable as monomers bi) are also polyhydroxyolefins, preferably those having 2 terminal hydroxyl groups, for example alpha-omega-dihydroxypolybutadiene, alpha-omega- dihydroxypolymethacrylate esters or alpha-omega-dihydroxypolyacrylate esters as monomers. Such compounds are disclosed in EP-A 622 378 for example. Further suitable polyols are polyacetals, polysiloxanes and alkyd resins.

[0178] It is preferable when at least 95 mol% of the diols bi) are polyester diols and / or polytetrahydrofuran. It is particularly preferable to employ exclusively polyesterdiols and / or polytetrahydrofuran as diols bi).

[0179] The hardness and the modulus of elasticity of the polyurethanes can be increased when as diols (b) not only the diols bi) but also low-molecular-weight diols b2) having a molecular weight of about 60 to 500, preferably of 62 to 200 g / ml, are employed. Employed monomers b2) especially include the synthesis components of the short-chain alkanediols recited for the production of polyester polyols, wherein the unbranched diols having 2 to 12 carbon atoms and an even number of carbon atoms and also pentane-1 ,5-diol and neopentyl glycol are preferred. Contemplated diols b2) include for example ethylene glycol, propane-1 , 2-diol, propane-1 , 3-diol, butane-1 ,3-diol, butene-1 ,4-diol, butyne-1 ,4-diol, pentane-1 ,5-diol, neopentyl glycol, bis(hydroxymethyl)cyclohexanes such as 1 ,4- bis(hydroxymethyl)cyclohexane, 2-methylpropane-1 , 3-diol, methylpentanediols, furthermore diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, dibutylene glycol and polybutylene glycols. Preferred alcohols are those of the general formula HO-(CH2)X-OH, wherein x is a number from 1 to 20, preferably an even number from 2 to 20. Examples thereof are ethylene glycol, butane-1 ,4- diol, hexane-1 ,6-diol, octane-1 , 8-diol and dodecane-1 ,12-diol. Neopentyl glycol is also preferred.

[0180] In order to ensure that the polyurethanes are water-dispersible, the polyurethanes comprise as a synthesis component monomers (c) which are distinct from the components (a) and (b) and bear at least one isocyanate group or at least one isocyanate-reactive group and moreover bear at least one hydrophilic group or a group which can be converted into a hydrophilic group. Hereinbelow, the term "hydrophilic groups or potentially hydrophilic groups" is abbreviated to "(potentially) hydrophilic groups". The (potentially) hydrophilic groups react with isocyanates substantially more slowly than the functional groups of the monomers used to construct the polymer main chain. The proportion of components comprising (potentially) hydrophilic groups in the total amount of components (a) to (f) is generally measured such that the molar amount of the (potentially) hydrophilic groups (preferably anionic or potentially anionic groups) based on the amount by weight of all monomers (a) to (e) is 30 to 1000, preferably 50 to 500 and particularly preferably 80 to 300 mmol / kg. The (potentially) hydrophilic groups may be nonionic or preferably (potentially) ionic hydrophilic groups.

[0181] Contemplated nonionic hydrophilic groups include in particular polyethylene glycol ethers composed of preferably 5 to 100, preferably 10 to 80, ethylene oxide repeating units. The content of polyethylene oxide units is generally 0% to 10% by weight, preferably 0% to 6% by weight, based on the amount by weight of all monomers (a) to (e). Preferred monomers comprising nonionic hydrophilic groups are polyethylene oxide diols comprising at least 20% by weight of ethylene oxide, polyethylene oxide monools and the reaction products of a polyethylene glycol and a diisocyanate which bear a terminally etherified polyethylene glycol radical. Such diisocyanates and processes for their production are recited in patent documents US-A 3,905,929 and US-A 3,920,598.

[0182] Ionic hydrophilic groups are especially anionic groups, such as the sulfonate, carboxylate and the phosphate group in the form of their alkali metal or ammonium salts, and cationic groups, such as ammonium groups, in particular protonated tertiary amino groups or quaternary ammonium groups. Potentially ionic hydrophilic groups are especially those which may be converted into the abovementioned ionic hydrophilic groups by simple neutralization, hydrolysis or quaternization reactions, i.e. carboxylic acid groups or tertiary amino groups for example. (Potentially) 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.

[0183] (Potentially) cationic monomers (c) of particular practical importance are especially monomers comprising tertiary amino groups, for example: tris(hydroxyalkyl)amines, N,N’- bis(hydroxyalkyl)alkylamines, N-hydroxyalkyldialkylamines, tris(aminoalkyl)amines, N,N’- bis(aminoalkyl)alkylamines, N-aminoalkyldialkylamines, wherein the alkyl radicals and alkanediyl units of these tertiary amines are independently of one another composed of 1 to 6 carbon atoms. Also contemplated are polyethers comprising tertiary nitrogen atoms and preferably two terminal hydroxyl groups, such as are obtainable in a manner customary per se for example by alkoxylation of amines comprising two hydrogen atoms attached to amine nitrogen, for example methylamine, aniline or N,N'-dimethylhydrazine. Such polyethers generally have a molar weight of between 500 and 6000 g / mol. These tertiary amines are converted into the ammonium salts either with acids, preferably strong mineral acids such as phosphoric acid, sulfuric acid, hydrohalic acids, or strong organic acids or by conversion with suitable quaternization agents such as Ci- to C6-alkyl halides or benzyl halides, for example bromides or chlorides.

[0184] Contemplated monomers comprising (potentially) anionic groups typically include aliphatic, cycloaliphatic, araliphatic or aromatic carboxylic acids and sulfonic acids bearing at least one alcoholic hydroxyl group or at least one primary or secondary amino group. Preference is given to dihydroxyalkylcarboxylic acids, especially comprising 3 to 10 carbon atoms, as also described in US 3,412,054. Preferred compounds include in particular compounds of the general formula in which R71and R72represent a Ci- to C4-alkanediyl (unit) and R73represents a Ci- to C4- alkyl (unit), especially dimethylolpropionic acid (DMPA). Corresponding dihydroxysulfonic acids and dihydroxyphosphonic acids such as 2,3-dihydroxypropanephosphonic acid are also suitable. Also suitable are dihydroxy compounds having a molecular weight of more than 500 to 10 000 g / mol and comprising at least 2 carboxylate groups, as disclosed in DE-A 39 11 827. These are obtainable by reacting dihydroxy compounds with tetracarboxylic dianhydrides, such as pyromellitic dianhydride or cyclopentanetetracarboxylic dianhydride in a molar ratio of 2:1 to 1.05:1 in a polyaddition reaction. Suitable dihydroxy compounds are in particular the monomers (b2) cited as chain extenders and the diols (b1).

[0185] Contemplated monomers (c) comprising isocyanate-reactive amino groups also include aminocarboxylic acids such as lysine, beta-alanine or the adducts, cited in DE-A 20 34 479, of aliphatic diprimary diamines onto alpha, beta-unsaturated carboxylic or sulfonic acids. Such compounds for example conform to the formula

[0186] H2N-R74-NH-R75-X (C2) in which R74and R75independently of one another represent a Ci- to C6-alkanediyl unit, preferably 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 the corresponding alkali metal salts, wherein sodium is a particularly preferred counterion. Also particularly preferred are the adducts of the abovementioned aliphatic diprimary diamines onto 2-acrylamido-2-methylpropanesulfonic acid, as described for example in DE-B 1 954 090.

[0187] Where monomers containing potentially ionic groups are employed, their conversion into the ionic form may take place before, during, but preferably after the isocyanate polyaddition, since the solubility of the ionic monomers in the reaction mixture is frequently no more than poor. Neutralizing agents are for example ammonia, NaOH, triethanolamine (TEA), triisopropylamine (TIPA) or morpholine, and derivatives thereof. The sulfonate or carboxylate groups are especially preferably present in the form of their salts with an alkali metal ion or with an ammonium ion as the counterion.

[0188] The monomers (d) which are distinct from the monomers (a) to (c) and which are optionally also constituents of the polyurethane are generally used for crosslinking or chain extension. They are generally more than dihydric nonphenolic alcohols, amines comprising 2 or more primary and / or secondary amino groups and compounds bearing one or more primary and / or secondary amino groups in addition to one or more alcoholic hydroxyl groups. Alcohols having a hydricity greater than 2 and which may be used to establish a certain degree of branching or crosslinking are, for example, trimethylolpropane, glycerol and sugar.

[0189] Also contemplated are monoalcohols which carry not only the hydroxyl group but also a further isocyanate-reactive group such as monoalcohols having one or more primary and / or secondary amino groups, for example monoethanolamine. Polyamines having 2 or more primary and / or secondary amino groups are primarily used when the chain extension and / or crosslinking is to take place in the presence of water since amines generally react with isocyanates more rapidly than alcohols or water. This is often necessary when aqueous dispersions of crosslinked polyurethanes or polyurethanes of high molecular weight are desired. The procedure in such cases comprises producing prepolymers comprising isocyanate groups, rapidly dispersing said prepolymers in water and subsequently chainextending or crosslinking said prepolymers by adding compounds comprising a plurality of isocyanate-reactive amino groups.

[0190] Amines suitable for this purpose are generally polyfunctional amines in the molecular weight range from 32 to 500 g / mol, preferably from 60 to 300 g / mol, which comprise at least two amino groups selected from the group of the primary and secondary amino groups.

[0191] Examples thereof are diamines such as diaminoethane, diaminopropanes, diaminobutanes, diaminohexanes, piperazine, 2,5-dimethylpiperazine, amino-3-aminomethyl-3,5,5- trimethylcyclohexane (isophoronediamine, IPDA), 4,4’-diaminodicyclohexylmethane, 1 ,4- diaminocyclohexane, aminoethyl ethanolamine, hydrazine, hydrazine hydrate or triamines such as diethylenetriamine or 1 ,8-diamino-4-aminomethyloctane. The amines may also be employed in blocked form, for example in the form of the corresponding ketimines (see, for example, CA-A 1 129 128), ketazines (cf., for example, US-A 4,269,748) or amine salts (see US-A 4,292,226). Oxazolidines, as are used, for example, in US-A 4,192,937, also represent capped polyamines which can be used for producing the polyurethanes for chain extension of the prepolymers. Use of such capped polyamines generally comprises mixing said polyamines with the prepolymers in the absence of water and subsequently mixing this mixture with the dispersion water or a portion of the dispersion water, thus releasing the corresponding polyamines hydrolytically. It is preferable to use mixtures of di- and triamines, particularly preferably mixtures of isophorone diamine (IPDA) and diethylene triamine (DETA).

[0192] The polyurethanes preferably comprise 1 to 30 mol%, particularly preferably 4 to 25 mol%, based on the total amount of the components (b) and (d) of a polyamine comprising at least 2 isocyanate-reactive amino groups as monomers (d). Higher than difunctional isocyanates may also be used as monomers (d) for the same purpose. Commercially available compounds are, for example, the isocyanurate or the biuret of hexamethylene diisocyanate. Monomers (e) that are optionally co-used are monoisocyanates, monoalcohols and monoprimary and -secondary amines. The proportion thereof is generally not more than 10 mol%, based on the total molar amount of the monomers. These monofunctional compounds typically bear further functional groups such as olefinic groups or carbonyl groups and serve to introduce functional groups into the polyurethane which make the dispersal or crosslinking or further polymer-analogous reaction of the polyurethane possible. Contemplated therefor are monomers such as isopropenyl-a,a’-dimethylbenzyl isocyanate (TMI) and esters of acrylic or methacrylic acid such as hydroxyethyl acrylate or hydroxyethyl methacrylate. Coatings having a particularly good profile of properties are obtained especially when the monomers (a) employed are substantially only aliphatic diisocyanates, cycloaliphatic diisocyanates or araliphatic diisocyanates. This monomer combination is superbly complemented as component (c) by alkali metal salts of diaminosulfonic acid; very particularly by N-(2-aminoethyl)-2-aminoethanesulfonic acid and its corresponding alkali metal salts, wherein the Na salt is most suitable, and a mixture of DETA and IPDA as component (d).

[0193] Also preferred are polyurethanes, wherein the diisocyanates a) are selected from diisocyanates of the formula X(NCO)2, wherein X represents an acyclic aliphatic hydrocarbon radical having 4 to 15 carbon atoms, a cycloaliphatic hydrocarbon radical having 6 to 15 carbon atoms, an aromatic hydrocarbon radical having 6 to 15 carbon atoms or an araliphatic hydrocarbon radical having 7 to 15 carbon atoms, preferably selected from the group consisting of hexamethylene diisocyanate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, 2,6-diisocyanatotoluene, 2,4- diisocyanatotoluene and tetramethylxylylene diisocyanate or a mixture thereof; the diols b1) are selected from polyester diols, polycarbonate diols and polyether diols; and the compound c) is selected from dihydroxycarboxylic acids, diaminocarboxylic acids and diaminosulfonic acids.

[0194] The way in which the molecular weight of the polyurethanes may be adjusted through choice of the proportions of the mutually reactive monomers and of the arithmetic mean of the number of reactive functional groups per molecule is common general knowledge in the field of polyurethane chemistry. The components (a) to (e) and their respective molar amounts are normally chosen such that the ratio A : B where A is the molar amount of isocyanate groups and

[0195] B is the sum of the molar amount of hydroxyl groups and the molar amount of functional groups which are capable of reacting with isocyanates in an addition reaction, is 0.5:1 to 2:1 , preferably 0.8:1 to 1.5:1 , particularly preferably 0.9:1 to 1.2:1. It is very particularly preferable when the ratio A :B is very close to 1 :1. The monomers (a) to (e) employed bear on average typically from 1 .5 to 2.5, preferably from 1.9 to 2.1 and particularly preferably 2.0 isocyanate groups or functional groups capable of reacting with isocyanates in an addition reaction.

[0196] The polyaddition of the components (a) to (e) to produce the polyurethane is preferably carried out at reaction temperatures of up to 180°C, preferably up to 150°C, under standard pressure or under autogenous pressure. The production of polyurethanes and of aqueous polyurethane dispersions is known to those skilled in the art.

[0197] In this context an aqueous polyurethane dispersion is to be understood as meaning a dispersion which has an aqueous solvent as the continuous phase. Suitable aqueous solvents are water and mixtures of water with water-miscible solvents, for example alcohols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, n- hexanol and cyclohexanol; glycols, such as ethylene glycol, propylene glycol and butylene glycol; the methyl or ethyl ethers of dihydric alcohols, diethylene glycol, triethylene glycol, polyethylene glycols having number-average molecular weights up to about 3000, glycerol and dioxane, and ketones, such as acetone in particular. In one specific embodiment the polyurethane dispersion is substantially free from organic solvents. “Substantially free from organic solvents” is to be understood as meaning that the proportion of organic solvents is not more than 5% by weight, particularly preferably not more than 1% by weight, in particular not more than 0.1% by weight, based on the total weight of the solvent.

[0198] In a preferred embodiment the production of the polyurethanes is carried out in the presence of at least one organic solvent. Preferred organic solvents for production of the polyurethanes are ketones, such as acetone and methyl ethyl ketone, and N- methylpyrrolidone. Particular preference is given to using acetone. If an at least partially water-miscible solvent is used to produce the polyurethanes, the polyurethane dispersion may contain not only water but also the organic solvent used for production. It will be appreciated that the production of the polyurethane dispersions may be carried out in the presence of at least one organic solvent, with said solvent subsequently being partially or preferably completely removed and replaced with water.

[0199] Compositions and uses of aqueous polymer adhesives

[0200] In the aqueous adhesive compositions the adhesive polymer is present in amounts preferably of from 15 to 75 wt.-%, more preferably from 20 to 70 wt.-%. or from 30 to 60 wt.- % or from 40 to 55 wt.-%.

[0201] The aqueous adhesives may be formulated with typical additives. Typical additives are, for example, defoamers, preservatives (e.g. biocides), catalysts, drying agents, antistatic agents, flame retardants, flow control agents, thickeners (preferably associative thickeners), thixotropic agents, surfactants, protective colloids, viscosity modifiers, plasticizers, levelling agents, tackifiers, dispersing aids, wetting agents, chelating agents, filler, dyes, pigments, coloring agents and crosslinking agents. For better wetting of surfaces the polymer dispersions may include in particular wetting agents, for example fatty alcohol ethoxylates, alkylphenol ethoxylates, nonylphenol ethoxylates or sodium dodecyl sulfonates. The amount of each of the additives is preferably (unless otherwise noted) 0.05% to 5% by weight, especially 0.25% to 3% by weight, based on the total weight of the aqueous polymer dispersion. For better wetting of surfaces the pressure-sensitive adhesives may include in particular wetting agents, for example fatty alcohol ethoxylates, alkylphenol ethoxylates, sulfosuccinic esters, nonylphenol ethoxylates, polyoxyethylene / polyoxypropylene copolymers or sodium dodecyl sulfonates. Defoaming agents are oil-based defoamers, water-based defoamers or silicone-based defoamers. Oil based defoamers have an oil carrier. The oil might be mineral oil, vegetable oil, white oil or any other oil that is insoluble in the foaming medium. An oil based defoamer also contains a wax and / or hydrophobic silica to boost the performance. Typical waxes are ethylene bis-stearamide (EBS), paraffin waxes, ester waxes and fatty alcohol waxes. These products might also have surfactants to improve emulsification and spreading in the foaming medium. Preferred defoaming agents are silicone oils, hydrophobized silica particles, wax particles, natural fatty acid oils and paraffins (preferably aromatics-free white oils). Water based defoamers are oils and waxes dispersed in a water base. The oils can be mineral oil or vegetable oils and the waxes can be fatty alcohols, fatty acid soaps or fatty acid esters. Silicone-based defoamers are polymers with silicon backbones such as polydimethylsiloxane. These might be delivered as an oil or a water-based emulsion. The silicone compound can consist of a hydrophobic silica dispersed in a silicone oil. Emulsifiers are added to ensure that the silicone spreads fast and well in the foaming medium. The silicone compound might also contain silicone glycols and other modified silicone fluids. EO / PO based defoamers contain polyethylene glycol and polypropylene glycol copolymers. They are delivered as oils, water solutions, or water-based emulsions. EO / PO copolymers normally have good dispersing properties and are often well suited when deposit problems are an issue.

[0202] A tackified pressure-sensitive adhesive composition preferably comprises (based on solids) 60 - 95 parts by weight of pressure-sensitive adhesive polymer, 5 - 40 parts by weight of tackifier and 0 - 10 parts by weight of further additives.

[0203] A non-tackified pressure-sensitive adhesive composition preferably comprises (based on solids)

[0204] 90 - 99.75 parts by weight of pressure-sensitive adhesive polymer and 0 - 10 parts by weight of further additives. For example

[0205] 95- 99.75 parts by weight of pressure-sensitive adhesive polymer,

[0206] 0.1 - 1 parts by weight per 100 parts by weight of polymer of at least one wetting agent , preferably a dialkyl sulfosuccinate,

[0207] 0.1 - 3 parts by weight per 100 parts by weight of polymer of at least one thickening agent, preferably an associative polyurethane thickener,

[0208] 0.05 - 1 parts by weight per 100 parts by weight of polymer of at least one defoaming agent, preferably selected from silicones, paraffins and white oils. A tackifier is a polymeric or oligomeric additive for adhesive polymers or generally for elastomers which increases their autoadhesion (tack, inherent tack, self-adhesion) so that after short, light contact pressure they adhere to surfaces firmly. Tackifiers include for example natural resins, such as colophony resins and the derivatives thereof formed by disproportionation or isomerization, polymerization, dimerization or hydrogenation or terpene resins. These may be in their salt form (with for example monovalent or polyvalent counterions (cations)) or preferably in their esterified form. Alcohols used for esterification may be monohydric or polyhydric. Examples include methanol, ethanediol, diethylene glycol, triethylene glycol, 1 ,2,3-propanethiol, pentaerythritol. Also employable are hydrocarbon resins, for example coumarone-indene resins, polyterpene resins, hydrocarbon resins based on unsaturated CH compounds, such as butadiene, pentene, methylbutene, isoprene, piperylene, divinylmethane, pentadiene, cyclopentene, cyclopentadiene, cyclohexadiene, styrene, alpha-methylstyrene, vinyltoluene. Tackifiers are known for example from Adhesive Age, July 1987, pages 19-23 or Polym. Mater. Sci. Eng. 61 (1989), pages 588-592. Polyacrylates having a low molar weight can also be used as tackifiers. These polyacrylates preferably have a weight-average molecular weight Mwless than 50 000, in particular less than 30 000. The polyacrylates preferably consist to an extent of at least 60% by weight, in particular at least 80% by weight, of Ci-C8alkyl (meth)acrylates. Suitable tackifiers include for example the low molecular weight polymers and oligomers described in WO 2013 / 117428 having a weight-average molecular weight of less than 50 000 and a glass transition temperature of not less than -40°C to not more than 0°C, preferably of not less than -35°C to not more than 0°C, producible by emulsion polymerization in the presence of at least one molecular weight regulator and producible from a monomer mixture comprising at least 40% by weight of at least one C1- to C20-alkyl (meth)acrylate. Preferred tackifiers include natural or chemically modified colophony resins. Colophony resins consist predominantly of abietic acid or abietic acid derivatives. Most preferred tackifiers are esters of hydrogenated rosin. Examples are pentaerythritol ester of hydrogenated rosin (e.g. Foral® 105 with a softening point of 95-103 °C) or glycerol ester of hydrogenated wood rosin (e.g. Foral® 85 with a softening point of 80-88 °C). The softening point is preferably from 80 to 110 °C, more preferably from 90 to 110 °C, measured by ring and ball method (according to ISO 4625- 1 :2020).

[0209] In the process for producing laminates the lamination adhesive is applied to the large- surface-area substrates to be bonded (such as polymer films), preferably with an adhesive layer thickness of 0.1 to 20 g / m2, more preferably 1 to 7 g / m2, by means, for example, of knife coating, spreading, etc. Typical coating techniques may be employed, examples being roller coating, reverse roller coating, gravure roller coating, reverse gravure roller coating, brush coating, rod coating, spray coating, air brush coating, meniscus coating, curtain coating or dip coating. After a short time for the water of the dispersion or organic solvents to evaporate (preferably after 1 to 60 seconds), the coated substrate may then be laminated with a second substrate, the temperature can be, for example, 20 to 200°C, preferably 20 to 100°C, and the pressure can be, for example, 100 to 3000 kN / m2, preferably 300 to 2000 kN / m2. The aqueous polymer dispersion adhesives can be used as lamination adhesives as a one- component composition, i.e. without additional crosslinking agents or as a two-component composition including at least one crosslinking agent as second component. Suitable crosslinking compounds are for example polyisocyanates which are obtainable by reacting at least one monomeric isocyanate. The monomeric isocyanates used to obtain the polyisocyanate may be aromatic, aliphatic or cycloaliphatic, preferably aliphatic or cycloaliphatic, which is referred to for short in this text as (cyclo)aliphatic; aliphatic isocyanates are particularly preferred. Aromatic isocyanates are those which comprise at least one aromatic ring system, i.e. both purely aromatic and araliphatic compounds. Cycloaliphatic isocyanates are those which comprise at least one cycloaliphatic ring system. Aliphatic isocyanates are those which comprise exclusively linear or branched chains, in other words acyclic compounds. The monomeric isocyanates are preferably diisocyanates bearing exactly two isocyanate groups.

[0210] Preferably, the polyisocyanates are the following compounds:

[0211] 1) Polyisocyanates which have isocyanurate groups and derive from aromatic, aliphatic and / or cycloaliphatic diisocyanates. Particular preference here is given to the corresponding aliphatic and / or cycloaliphatic isocyanato-isocyanurates and in particular to those based on hexamethylene diisocyanate and isophorone diisocyanate. These present isocyanurates are, in particular, trisisocyanatoalkyl and / or trisisocyanatocycloalkyl isocyanurates, which are cyclic trimers of the diisocyanates, or are mixtures with their higher homologs containing more than one isocyanurate ring. The isocyanatoisocyanurates generally have an NCO content of 10% to 30% by weight, in particular 15% to 25% by weight, and an average NCO functionality of 2.6 to 8.

[0212] 2) Polyisocyanates having uretdione groups, with aromatically, aliphatically and / or cycloaliphatically bonded isocyanate groups, preferably aliphatically and / or cycloaliphatically bonded, and in particular those derived from hexamethylene diisocyanate or isophorone diisocyanate. Uretdione diisocyanates are cyclic dimerization products of diisocyanates. The polyisocyanates having uretdione groups are obtained in this context in a mixture with other polyisocyanates, especially those mentioned under 1). To this end, the diisocyanates are converted under reaction conditions under which both uretdione groups and the other polyisocyanates are formed, or the uretdione groups are formed first and these are subsequently converted to the other polyisocyanates, or the diisocyanates are first converted to the other polyisocyanates and these are then converted to products containing uretdione groups.

[0213] 3) Biuret group-containing polyisocyanates having aromatically, cycloaliphatically or aliphatically bonded, preferably cycloaliphatically or aliphatically bonded, isocyanate groups, especially tris(6-isocyanatohexyl)biuret or mixtures thereof with higher homologs thereof. These polyisocyanates having biuret groups preferably (particularly 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.

[0214] 4) Urethane and / or allophanate group-containing polyisocyanates having aromatically, aliphatically or cycloaliphatically bonded, preferably aliphatically or cycloaliphatically bonded, isocyanate groups, as can be obtained, for example, by reaction of excess amounts of diisocyanate, for example hexamethylene diisocyanate or isophorone diisocyanate, with mono- or polyhydric alcohols (A). These polyisocyanates having urethane and / or allophanate groups generally have an NCO content of 12% to 24% by weight and an average NCO functionality of 2.3 to 4.5. Polyisocyanates of this kind containing urethane and / or allophanate groups may be prepared uncatalyzed or, preferably, in the presence of catalysts, such as ammonium carboxylates or ammonium hydroxides, for example, or allophanatization catalysts, such as Zn(ll) compounds, for example, in each case in the presence of monohydric, dihydric or polyhydric, preferably monohydric, alcohols. ) Polyisocyanates comprising oxadiazinetrione groups, derived preferably from hexamethylene diisocyanate or isophorone diisocyanate. Such polyisocyanates comprising oxadiazinetrione groups are obtainable from diisocyanate and carbon dioxide. ) Polyisocyanates comprising iminooxadiazinedione groups, derived preferably from hexamethylene diisocyanate, pentamethylene diisocyanate or isophorone diisocyanate. Such polyisocyanates comprising iminooxadiazinedione groups are preparable from diisocyanates by means of specific catalysts. They are typically present in a mixture with polyisocyanates 1), optionally also with 2) and / or 4). ) Uretonimine-modified polyisocyanates. ) Carbodiimide-modified polyisocyanates. ) Hyperbranched polyisocyanates, as known for example from DE-A1 10013186 or DE-A1 10013187. 0) Polyurethane-polyisocyanate prepolymers, from di- and / or polyisocyanates with alcohols. 1) Polyurea-polyisocyanate prepolymers. 2) The polyisocyanates 1)-11), preferably 1), 3), 4) and 6), after preparation thereof, can be converted to biuret group-containing or urethane / allophanate group-containing polyisocyanates having aromatically, cycloaliphatically or aliphatically bonded, preferably (cyclo)aliphatically bonded, isocyanate groups. Biuret groups are formed, for example, by addition of water or reaction with amines. Urethane and / or allophanate groups are formed by reaction with monohydric, dihydric or polyhydric, preferably monohydric, alcohols, optionally in the presence of suitable catalysts. These biuret or urethane / allophanate group-containing polyisocyanates generally have an NCO content of 18% to 22% by weight and an average NCO functionality of 2.8 to 6. 3) Hydrophilically modified polyisocyanates, i.e. polyisocyanates which, as well as the groups described under 1-12, comprise those which arise in a formal sense through addition of molecules having NCO-reactive groups and hydrophilizing groups onto the isocyanate groups of the above 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, with organic modification. They may be used here in solvent borne systems, more particularly as a co-component of the isocyanate component, preferably in waterborne applications. 14) Modified polyisocyanates for dual-cure applications, i.e. polyisocyanates which, as well as the groups described under 1-13, comprise those which arise in a formal sense through addition of molecules having NCO-reactive groups and groups crosslinkable by UV or actinic radiation onto the isocyanate groups of the above molecules. These molecules are, for example, hydroxyalkyl (meth)acrylates and other hydroxyl-vinyl compounds.

[0215] The diisocyanates or polyisocyanates listed above may also be at least partly in blocked form. Preferred polyisocyanate crosslinking compounds are at least one polyisocyanate selected from the group consisting of isocyan urates, iminooxadiazinediones, biurets, uretdiones, urethanes, and allophanates; preferably from the group consisting of isocyanurates, urethanes and allophanates, more preferably from the group consisting of isocyanurates and allophanates, and it is especially a polyisocyanate containing isocyanurate groups. In one particularly preferred embodiment, the polyisocyanate comprises polyisocyanates which comprise isocyanurate groups and derive from 1 ,6- hexamethylene diisocyanate. In a further particularly preferred embodiment, the polyisocyanate is a mixture of polyisocyanates which comprise isocyanurate groups and derive from 1 ,6-hexamethylene diisocyanate, pentamethylene diisocyanate and from isophorone diisocyanate.

[0216] The films for producing laminated articles may be metalized or printed on the side that is coated with adhesive. Examples of suitable substrates include polymer films, more particularly thermoplastic polyolefins (TPO) such as polyethylene (PE), oriented polypropylene (OPP), unoriented polypropylene (CPP), polyamide (PA), polyester (preferably polyethylene terephthalate (PET)), polyacetate, ethylene / vinyl acetate copolymers (EVA), ASA (acrylnitrile / styrene / acryl acid ester copolymers), PUR (polyurethane), polyvinylchloride (PVC), preferably soft-PVC, poly(meth)acrylates, polycarbonates or their alloys, cellophane, polymer films (vapor-)coated with metal, e.g., with aluminum (metalized films for short), or metal foils, of tin or aluminum, for example. The stated films and foils may be bonded with one another or with a foil or film of a different type - for example, polymer films with metal foils, different polymer films with one another, etc. The stated foils and films may also, for example, be printed with printing inks.

[0217] Use of aqueous polymer dispersion adhesives

[0218] The aqueous polymer dispersion adhesives can be used as lamination adhesives for producing laminates, i.e. for the bonding of substrates of large surface area, more particularly for the production of composite films or for the production of laminated 3-dimensional articles such as furniture or automobile parts using suitable lamination adhesives including adhesive polymers as described above. In the process for producing composite films, at least two films are bonded with one another using a lamination adhesive.

[0219] The aqueous polymer dispersion adhesives can be used as pressure-sensitive adhesives for producing self-adhesive articles. The articles are at least partially coated with the pressure-sensitive adhesive. The self-adhesive articles may be self-adhesive labels, self- adhesive tapes or self-adhesive films including graphic films and protective films. Suitable carrier materials are for example paper, plastic films and metal foils. The inventive self- adhesive tapes may be tapes of the above-mentioned substances coated on one or both sides. The inventive self-adhesive labels may be labels made of paper or a thermoplastic film. Adhesive tapes made of thermoplastic film are particularly preferred. Suitable thermoplastic films include for example films made of polyolefins (for example polyethylene or polypropylene), polyolefin copolymers, films made of polyesters (for example polyethylene terephthalate), polyvinyl chloride or polyacetate. The surfaces of the thermoplastic polymer films have preferably been corona-treated. Foamed carriers are also possible. The labels have been coated with adhesive on one side. Preferred substrates for the self-adhesive articles are paper and polymer films.

[0220] The self-adhesive articles have been at least partially coated with a pressure-sensitive adhesive on at least one surface. The adhesive may be applied to the articles by customary methods such as roller application, knife coating or spreading. The application rate is preferably 0.1 to 300 g, more preferably 2 to 150 g of solid per m2. Application is generally followed by a drying step for removal of the water. The water may be removed by drying at 50°C to 150°C for example. The thus obtained coated substrates are used for example as self-adhesive articles, such as adhesive labels, adhesive tapes, or adhesive films. To this end the carriers may be cut into adhesive tapes, labels, or films before or after application of the adhesive. The side of the substrates coated with pressure-sensitive adhesive may be covered with a release paper, for example with a siliconized paper, for later use. The substrates to which the self-adhesive articles may advantageously be applied may be metal, wood, glass, paper or plastic. The self-adhesive articles are especially suitable for bonding to packaging surfaces, cardboard boxes, plastic packaging, books, windows, vapor barriers, motor vehicle bodies, tires or vehicle body parts.

[0221] Preferred self-adhesive articles are self-adhesive labels, self-adhesive tapes and self- adhesive films.

[0222] The composition can additionally comprise further additives, such as, for example, sterically hindered amine stabilizers, UV-absorbers, phosphites, phosphonites, benzofuranones, indolinones, metal stearates, metal oxides, pigments, dyes, organophosphorus compounds, hydroxylamines, metal deactivators, nitrones, thiosynergists, peroxide scavengers, nucleating agents, fillers, reinforcing agents, plasticisers, lubricants, emulsifiers, rheology additives, catalysts, flow-control agents, optical brighteners, antistatic agents, blowing agents, biocides, slip- and leveling agents, wetting agents, dispersants, defoamers, matting agents, waxes, anti skinning additives, adhesion promoters, coalescents, rheology modifiers, sag control agents, thixotropic agents, flame retardants or mixtures thereof.

[0223] Examples of such further additives are given in W02008 / 000646, page 36, line 9 to page 43, line 4.

[0224] For instance, the further additives are encapsulated in polymeric particles as described in W02005 / 023878, W02007 / 104713, W02007 / 147726 and US2008 / 0146448 or the further additives are effect substances encapsulated in polymeric particles as described therein. For example, the amount of further additives is from 0.1 to 40%, preferably 0.1 to 20%, more preferably 0.1 to 10%, most preferably 0.1 to 5%, by weight based on the weight of the component a) (i.e. organic material to be stabilised or solid binder material).

[0225] Other aspects of this invention are the use of a concentrated aqueous polymer dispersion as defined herein as stabilizer against thermal, oxidative or light-induced degradation of organic materials, which are susceptibel to thermal, oxidative or light induced degradation; and the use of a stabilizer compound of formula

[0226] (la), wherein o and p independently of one another are integers from 1 to 8, as stabilizer against thermal, oxidative or light-induced degradation of organic materials in combination with at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C, which prevents crystallization of the stabilizer compound (A) in the organic material, wherein the stabilizer compound of formula (I) and the stabilizer compound (B) are used in the form of the concentrated aqueous polymer dispersion as defined herein.

[0227] Of interest is a method for the stabilization of an organic material against against thermal, oxidative or light-induced degradation, which comprises admixing and / or applying to said material as stabiliser a concentrated aqueous polymer dispersion as described herein.

[0228] Materials and Methods

[0229] Irganox® 245 (CAS No. 36443-68-2):

[0230] (V-1).

[0231] Irganox® 245 DW is a 40 % active aqueous dispersion of Irganox® 245 in polyvinylalkohol (4%).

[0232] Irganox® 1010 (CAS No. 6683-19-8):

[0233] IRGANOX® 1520 L (CAS no. 110553-27-0; melting range: ca. 12-15 °C):

[0234] IRGANOX® 1035 (CAS no. 41484-35-9; melting point = 78 °C):

[0235] (B-3). Didodecyl-3,3'-thiodipropionate (CAS no. 123-28-4; melting point = 39-41 °C):

[0236] (B-9).

[0237] Disponil® FES 32 EVO: anionic surfactant; fatty alcohol ether sulfate + 4 EO, sodium salt, 31% active in water (BASF SE).

[0238] Acronal® V 215: (Tg: -43 °C): Aqueous dispersion of an acrylate copolymer containing carboxyl groups (BASF SE).

[0239] Butofan® LS 103: (Tg: -48 °C): Aqueous dispersion of a butadiene-styrene copolymer with carboxyl groups. Used to manufacture pressure sensitive adhesives for self-adhesive articles (BASF SE).

[0240] Licity® 2688: Aqueous dispersion based on styrene and 1 ,3-butadien (BASF SE). Especially suitable for Si-rich and pure Si-anodes.

[0241] The following abbreviations were used: wt%: % by weight,

[0242] SMA: stearyl methacrylate,

[0243] MMA: methyl methacrylate,

[0244] MAA: methacrylic acid, BDDA: butanediol diacrylate,

[0245] AMP90: 90% aq. solution of 2-amino-2-methylpropanol,

[0246] D5o: particle size at 50% of the volume distribution,

[0247] PDI: polydispersity = sigma value of distribution I D50 value,

[0248] SC%: dry solid content in percent,

[0249] DLS: dynamic light scattering, nm: nanometers., nd: value not determined.

[0250] Test Methods

[0251] Particle size was determined by using a NANO-flex particle sizer from Microtrac using 780 nm laser light (3 mW) at a 1800scattering angle. Measurements were done with samples tel quel diluted to the required concentration with demineralized water at room temperature. D50 values reported refer to the volume fraction of the distribution and the polydispersity was calculated from the sigma value of the distribution divided by the D50 value.

[0252] Solid contents were measured on a Mettler Toledo HR 73 halogen dryer at 150 °C until a constant weight of a 0.5 to 0.8 g sample. The result is expressed in dry wt%.

[0253] Heat stability tests were performed according to ASTM D 4499 (DIN EN ISO 10363), wherein heat aging was done at the temperatures given in the respective section.

[0254] Color values were given in Gardner color number index according to ASTM D-6166. Higher numbers mean higher color, i.e. higher oxidation. The effectiveness of a stabilizer package can be ranked by the color number. Keeping lower numbers for a longer time mean better effectiveness of the radical scavenger package.

[0255] The adhesion was tested using a probe tack tester (Testing Machines Inc., machine 80-02- 01) according to ASTM D2979-95 (DIN 55405). Higher gram value means higher tack.

[0256] In addition, adhesion testing was done with a peel tests at 180° according to FINAT FTM1 (FINAT Technical Handbook 7th edition, 2005). Higher values mean higher peel strength. Cohesion testing was done with resistance to static shear according to FINAT FTM 8 (respectively ASTM D-6463). Higher values mean higher cohesion.

[0257] Shore A Hardness was determined according to DIN 53505 using a shore scale A durometer. Lower hardness means higher deterioration of the sealant compound.

[0258] Viscosity was determined with a Brookfield Rheometer using an LV-02 spindle at 23 °C and 60 rpm. The results are expressed in mPas.

[0259] Synthesis Example 1 (EC_B-3_SE1

[0260] Encapsulation of IRGANOX® 1035 40.0 g of Irganox® 1035 was dissolved in 34.20 g of methyl methacrylate (MMA), 3.04 g of stearyl methacrylate (SMA), 0.11 g of 1 ,4-butanediol diacrylate and 0.76 g of methacrylic acid at 40 °C to a homogeneous solution. To this organic phase, a solution of 10.06 g of Disponil® FES 32 EVO in 91 .80 g of deionised water and 10.0 g of glycerol was added. After stirring for 20 min, followed by 20 min of ultra-sound treatment (Bandelin Sonoplus, Generator GM 2200, 200 W, 20 kHz, 60% power), a stable emulsion with an average droplet size of 90 nm was obtained.

[0261] The emulsion was heated to 40 °C under an N2-atmosphere in a four-necked flask equipped with an overhead stirrer, thermometer, cooler and N2-inlet, and t-butyl hydroperoxide (1.90 g, 10% in H2O) was added.

[0262] The emulsion was continuously stirred at 40 °C by the mechanical stirrer, while a solution of 0.38 g of sodium hydroxymethanesulfinate dissolved in 7.54 g of water was prepared. A portion of 30% of this solution was added at once, leading to an exotherm to 57 °C after 25 min. At this point, the remainder sodium hydroxymethanesulfinate solution was added over a period of 1 hour at 60 °C.

[0263] After addition, the reaction mixture was subsequently stirred at 60 °C for one hour, then cooled to room temperature. The pH of the dispersion was adjusted to 8.2 by addition of amine (0.25 g of AMP90) and filtered via a 150 pm filter. The resulting low viscous milky dispersion had a particle size D5o of 80 nm (dynamic light scattering DLS) and a PDI of 0.246. The final active content of the dispersion was 20 wt% of Irganox® 1035 and the solid content was 44.8 wt%.

[0264] The residual monomer content (main component MMA) was determined by headspace GC- MS at 100 ppm.

[0265] Synthesis Example 2 (EC_A-1_B-1_SE2)

[0266] Encapsulation of Irganox® 1010 ( (A-1)) and

[0267] IRGANOX® 1520

[0268] 23.0 g of Irganox® 1010 and 23.0 g of Irganox® 1520 L were dissolved in 39.33 g of methyl methacrylate (MMA), 3.50 g of stearyl methacrylate (SMA), 0.13 g of 1 ,4-butanediol diacrylate and 0.87 g of methacrylic acid at 45 °C to a homogeneous solution. To this organic phase, a solution of 11 .57 g Disponil® FES 32 EVO in 93.62 g of deionised water and 23.0 g of glycerol was added. After stirring for 15 min, followed by 20 min of ultra-sound treatment (Bandelin Sonoplus, Generator GM 2200, 200 W, 20 kHz, 60% power), a stable emulsion with an average droplet size of 96 nm was obtained.

[0269] The emulsion was heated to 45 °C under an N2-atmosphere in a four-necked flask equipped with an overhead stirrer, thermometer, cooler and N2-inlet, and t-butyl hydroperoxide (2.19 g, 10% in H2O) was added.

[0270] The emulsion was continuously stirred at 45 °C by the mechanical stirrer, while a solution of 0.44 g of sodium hydroxymethanesulfinate dissolved in 8.7 g of water was prepared. A portion of 30% of this solution was added at once, leading to an exotherm to 57 °C after 30 min. At this point, the remainder sodium hydroxymethanesulfinate solution was added over a period of 1 hour at 60 °C.

[0271] After addition, the reaction mixture was subsequently stirred at 60 °C for one hour, then cooled to room temperature. The pH of the dispersion was adjusted to 8.1 by addition of amine (0.42 g of AMP90) and filtered via a 150 pm filter. The resulting low viscous milky dispersion had a particle size D5o of 85 nm (dynamic light scattering DLS) and a PDI of 0.395. The final active content of the dispersion was 20 wt% of Irganox® 1010 and Irganox® 1520 L in a 1 :1 ratio, and the solid content was 50.0 wt%.

[0272] The residual monomer content (main component MMA) was determined by headspace GC- MS at 1000 ppm.

[0273] Synthesis Example 3 (EC_A-1_B-3_SE3)

[0274] 23.0 g of Irganox® 1010 and 23.0 g of Irganox® 1035 were dissolved in 39.33 g of methyl methacrylate (MMA), 3.50 g of stearyl methacrylate (SMA), 0.13 g of 1 ,4-butanediol diacrylate and 0.87 g of methacrylic acid at 45 °C to a homogeneous solution. To this organic phase, a solution of 11 .57 g Disponil® FES 32 EVO in 93.62 g of deionised water and 23.0 g of glycerol was added. After stirring for 15 min, followed by 20 min of ultra-sound treatment (Bandelin Sonoplus, Generator GM 2200, 200 W, 20 kHz, 60% power), a stable emulsion with an average droplet size of 99 nm was obtained. The emulsion was heated to 45 °C under an N2-atmosphere in a four-necked flask equipped with an overhead stirrer, thermometer, cooler and N2-inlet, and t-butyl hydroperoxide (2.19 g, 10% in H2O) was added.

[0275] The emulsion was continuously stirred at 45 °C by the mechanical stirrer, while a solution of 0.44 g of sodium hydroxymethanesulfinate dissolved in 8.7 g of water was prepared. A portion of 30% of this solution was added at once, leading to an exotherm to 60 °C after 30 min. At this point, the remainder sodium hydroxymethanesulfinate solution was added over a period of 1 hour at 60 °C.

[0276] After addition, the reaction mixture was subsequently stirred at 60 °C for one hour, then cooled to room temperature. The pH of the dispersion was adjusted to 8.25 by addition of amine (0.39 g of AMP90) and filtered via a 150 pm filter. The resulting low viscous milky dispersion had a particle size D5o of 73 nm (dynamic light scattering DLS) and a PDI of 0.397. The final active content of the dispersion was 20 wt% of Irganox® 1010 and Irganox® 1035 in a 1 :1 ratio, and the solid content was 51.1 wt%.

[0277] The residual monomer content (main component MMA) was determined by headspace GC- MS at 390 ppm.

[0278] Synthesis Example 4 (EC_B-1_SE4)

[0279] Encapsulation of IRGANOX® 1520

[0280] 40.0 g of Irganox® 1520 L was dissolved in 36.0 g of methyl methacrylate (MMA), 3.20 g of stearyl methacrylate (SMA), 0.12 g of 1.4-butanediol diacrylate and 0.80 g of methacrylic acid at 25 °C to a homogeneous solution. To this organic phase, a solution of 10.32 g Disponil® FES 32 EVO in 98.46 g of deionised water was added. After stirring for 10 min, followed by 10 min of ultra-sound treatment (Bandelin Sonoplus, Generator GM 2200, 200 W, 20 kHz, 35% power), a stable emulsion with an average droplet size of 102 nm was obtained.

[0281] The emulsion was heated to 45 °C under an N2-atmosphere in a four-necked flask equipped with an overhead stirrer, thermometer, cooler and N2-inlet, and t-butyl hydroperoxide (2.0 g, 10% in H2O) was added.

[0282] The emulsion was continuously stirred at 45 °C by the mechanical stirrer, while a solution of 0.40 g of sodium hydroxymethanesulfinate dissolved in 7.93 g of water was prepared. A portion of 30% of this solution was added at once, leading to an exotherm to 53 °C after 25 min. At this point, the remainder sodium hydroxymethanesulfinate solution was added over a period of 1 hour at 60 °C.

[0283] After addition, the reaction mixture was subsequently stirred at 60 °C for one hour.

[0284] Then, 1.0 of of , t-butyl hydroperoxide (10% in H2O) followed by addition of a 4.8% solution of sodium hydroxymethanesulfinate over a period of 30 min at 60 °C. After stirring for 30 min at 60 °C, the reaction mixture was cooled to room temperature. The pH of the dispersion was adjusted to 8.8 by addition of amine (0.75 g of AMP90) and filtered via a 150 pm filter. The resulting low viscous milky dispersion had a particle size D5o of 108 nm (dynamic light scattering DLS) and a PDI of 0.343. The final active content of the dispersion was 20 wt% of Irganox® 1520L and the solid content was 40.59 wt%.

[0285] The residual monomer content (main component MMA) was determined by headspace GC- MS at 1300 ppm.

[0286] Synthesis Example 5 (EC_A-1_SE5)

[0287] Encapsulation of IRGANOX® 1010 (A-1)

[0288] 100.0 g of Irganox® 1010 was dissolved in 85.5 g of methyl methacrylate (MMA), 7.60 g of stearyl methacrylate (SMA), 0.29 g of 1 ,4-butanediol diacrylate and 1.90 g of methacrylic acid at 45 °C to a homogeneous solution. To this organic phase, a solution of 25.16 g Disponil® FES 32 EVO in 252.80 g of deionised water was added. After stirring for 15 min, followed by 20 min of ultra-sound treatment (Bandelin Sonoplus, Generator GM 2200, 200 W, 20 kHz, 35% power), a stable emulsion with an average droplet size of 182 nm was obtained.

[0289] The emulsion was heated to 45 °C under an N2-atmosphere in a four-necked flask equipped with an overhead stirrer, thermometer, cooler and N2-inlet, and t-butyl hydroperoxide (4.75 g, 10% in H2O) was added.

[0290] The emulsion was continuously stirred at 45 °C by the mechanical stirrer, while a solution of 0.95 g of sodium hydroxymethanesulfinate dissolved in 18.84 g of water was prepared. A portion of 30% of this solution was added at once, leading to an exotherm to 70 °C after 22 min. At this point, the remainder sodium hydroxymethanesulfinate solution was added over a period of 1 hour at 60 °C.

[0291] After addition, the reaction mixture was subsequently stirred at 60 °C for one hour, then cooled to room temperature. The pH of the dispersion was adjusted to 8.1 by addition of amine (0.50 g of AMP90) and filtered via a 150 pm filter. The resulting low viscous milky dispersion had a particle size D5o of 156 nm (dynamic light scattering DLS) and a PDI of 0.555. The final active content of the dispersion was 20 wt% of Irganox® 1010 and the solid content was 41 .32 wt%.

[0292] The residual monomer content (main component MMA) was determined by headspace GC- MS at 40 ppm.

[0293] Table 1a

[0294] 1> Synthesis Examples 1 to 4: Monomer: MMA mix; Anionic surfactant: 4 wt.% of Disponil® FES 32 EVO; ratio: A (wt. % additive(s)) / M (wt. % monomer(s)) = 20 / 19.

[0295] Table 1a - Mixed dispersions of encapsulated cpd. A-1 (EC_A-1_SE5) and encapsulated cpd. B-1 (EC_B-1_SE4)

[0296] Draw downs of the dispersions were prepared and the transparency of the draw downs was determined (see Table 2).

[0297] Table 2

[0298] The mixture of Irganox® 1010 and 1520 (EC_A-1_B-1_SE2) in one capsule is giving much better transparency than the encapsulated Irganox® 1010 (EC_A-1_SE5) alone.

[0299] Application Example 1

[0300] The antioxidant obtained according to Synthesis Examples 1 to 4 are mixed at 1 wt. % tel quel into Luphen® 3644 and casted with 10 g in an aluminium dish. The obtained samples are stored at 120° C and b* color values are collected over time (weeks). At the end of the testing Gardner color values are determined.

[0301] The combination of Irganox® 1520 L with Irganox® 1010 (EC_A-1_B-1_SE2) is resulting in best stabilization of color values. A second antioxidant which is liquid, or has a low melting point improves the solubility of the Irganox® 1010 inside the capsule.

[0302] Application Example 2 - Encapsulated mixtures of cpds. A-1 and B-1

[0303] The dispersions EN_A-1_B-1_SE2a and EN_A-1_B-1_SE2b are obtained in analogy to

[0304] Synthesis Example 2, except that different amounts of cpds. A-1 and B-1 are used.

[0305] The standard for determining the Hazen color number is the method DIN EN ISO 6271- 1 :2005-03 in bulk against an aqueous hydrochloric acid solution of potassium hexachloroplatinate(IV) / cobalt(ll) chloride as reference at a path length of 5 cm. a) Probe Tack Values [gr]

[0306] The combination of Irganox® 1520 L with Irganox® 1010 (M_1 , M_2, M_3 and in particular EC_A-1_B-1_SE2) is resulting in best tack retention. b) Color Values

[0307]

[0308] The combination of Irganox® 1520 L with Irganox® 1010 (M_1 , M_2, M_3 and in particular EC_A-1_B-1_SE2) is resulting in best stabilization of color values. c) Color Values

[0309] The combination or Irganox® 1010 and 1520 L in one shell is giving much better color readings than the encapsulated individual components.

Claims

Claims1. A concentrated aqueous polymer dispersion with an average particle size of less than 1000 nm, comprising a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b1) at least one stabilizer compound of formula(I), wherein o is an integer of 1 to 8; p is 0, or an integer of 1 to 8; q is 0, or 1 ; n is an integer 3, or 4;A is a 3, or 4 valent organic residue, which is selected fromwith the proviso that if A is an organic residue , o and p independently of one another are integers from 1 to 8; q is 1 and n is 4; and with the further proviso thatif A is an organic residueinteger from 1 to 8; p is 0, q is 0 and n is 3; especially a stabilizer compound of formula(A-1); b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant; or a concentrated aqueous polymer dispersion with an average particle size of less than 1000 nm, comprising a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b1) at least one stabilizer compound of formula (I), especially compound (A-1), b3) a non-ionic, cationic or anionic surfactant, and a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant.

2. The concentrated aqueous polymer dispersion according to claim 1 , wherein the at least one stabilizer (B) is selected from the group consisting of compounds of formulaunsubstituted Ci-C8alkyl group, Rband Rc, independently of one another, are linear Ci-C2oalkyl groups and n' and m', independently of one another, are integers from 1 to 8, in particular Rdis amethyl, ethyl or i-propyl group, n' and m' are 1 and Rband Rcare each a C8-Ci3alkyl group, with Rband Rccomprising preferably the same number of C atoms.The concentrated aqueous polymer dispersion according to claim 1 , or 2, wherein the at least one stabilizer (B) is selected from the group consisting ofmixtures thereof.

4. The concentrated aqueous polymer dispersion according to any of the preceding claims, wherein the ethylenically unsaturated monomer is selected from the group consisting of Ci-C2oalkyl acrylates, Ci-C2oalkyl methacrylates, acrylic acid, methacrylicacid, styrene, vinyltoluene, hydroxy-functional acrylates or methacrylates, acrylates or methacrylates derived from alkoxylated alcohols and multifunctional acrylates or methacrylates or mixtures thereof.

5. The concentrated aqueous polymer dispersion according to claim 4, wherein the ethylenically unsaturated monomer is a mixture of methylmethacrylate, stearyl- methacrylate, butanediol diacrylate and methacrylic acid.

6. The concentrated aqueous polymer dispersion according to any of the preceding claims, comprising a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence ofb1) a stabilizer compound of formula (A-1),b2) a stabilizer compound (B-1), and b3) an anionic surfactant, which is preferably selected from alkali and ammonium salts of sulphonic acid, dialkyl esters of succinic acid and sulfuric acid halfesters of ethoxylated alkanoles, especially poly(oxy-1 ,2-ethanediyl), a-sulfo-o-hydroxy-, C12-14- alkyl ethers, sodium salts.

7. The concentrated aqueous polymer dispersion according to any of the preceding claims, wherein the heterophase radical polymerization of at least one ethylenically unsaturated monomer is done in the presence of components (b1), (b2), (b3) and in addition (b4) at least one light stabilizer which is selected from light stabilizers offormula (III), whereinr halogen;R5and R8are independently of each other hydrogen, or Ci-C2oalkyl, especially hydrogen;Z is hydrogen, C2-C2oalkenyl, or said C2-C2oalkenyl, substituted by one to three — R44, — OR45, — COOR45, — OCOR45and / or interrupted by one to three — O — , — COO — , — OCO — or — CO — ; especially Ci-C24alkyl or C5-Ci2cycloalkyl; or said Ci-C24alkyl or said C5-Ci2cycloalkyl substituted by one to three — R44, — OR45, — COOR45, — OCOR45and / or interrupted by one to three — O — , — COO — , — OCO — or — CO — ;R44is C6-Cioaryl, C6-Ci0aryl substituted by one to three halogen, Ci-C8alkyl, Ci- C8alkoxy, or combinations thereof; C5-Ci2cycloalkyl; C7-Ci2phenylalkyl, Cz- C^phenylalkyl substituted on the phenyl ring by one to three halogen, Ci-C8alkyl, Ci- C8alkoxy, or combinations thereof;R45is defined as is R44; or R45is also hydrogen or Ci-C24alkyl;Ar2and Ar3are independently of each other selected from a group of the formula (D-2),(D-3), phenyl or phenyl substituted by one to three Ci-C6alkyl, halogen, hydroxy or Ci-Ci2alkoxy; naphthyl or naphthyl substituted by one to three Ci-C6alkyl, halogen, hydroxy or Ci-Ci2alkoxy; and(D-4);R51, R52, R53, R54and R55are independently of each other hydrogen, hydroxy, cyano, Ci-C2oalkyl, Ci-C2oalkoxy, Cz-C^phenylalkyl, C5-Ci2cycloalkyl, C5-Ci2cycloalkyloxy, or halogen;Z’ is as defined for Z; R6is as defined for R6, R5and R8are as defined for R5and R8, respectively; and light stabilizers of formula, whereinR1is hydrogen, Ci-Ci8alkyl, or Ci-Ci8alkyl which is substituted by phenyl,R2is hydrogen, Ci-Ci8alkyl, or is Ci-Ci8alkyl which is substituted by COOR25, Ci- Ci8alkoxy, hydroxyl, phenyl or C2-Ci8acyloxy;R3is hydrogen, halogen, Ci-Ci8alkyl, Ci-Ci8alkoxy, C2-Ci8acyloxy, phenyl, or is Ci- Ci2fluoroalkyl;R4is hydrogen, halogen, Ci-Ci8alkyl, Ci-Ci8alkoxy, C2-Ci8acyloxy, phenyl, or is Ci-Ci2fluoroalkyl; orR3and R4together form a ring;R25is hydrogen, Ci-Ci8alkyl or C4-C5oalkyl interrupted by one or more O and / orsubstituted by OH, or by , wherein R1, R3andR4are defined above.

8. A process for the preparation of a concentrated aqueous polymer dispersion with an average particle size of less than 1000 nm comprising the step(s) polymerizing at least one ethylenically unsaturated monomer in the presence of b1) at least a stabilizer compound of formula (I) defined in claim 1 ; b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant; or a process comprising the step(s) polymerizing at least one ethylenically unsaturated monomer in the presence of b1) at least a stabilizer compound of formula (I) defined in claim 1 ; b3) a non-ionic, cationic or anionic surfactant, and polymerizing at least one ethylenically unsaturated monomer in the presence of b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant.

9. A composition stabilized against thermal, oxidative or light-induced degradation which comprises,(A) an organic material susceptible to thermal, oxidative or light induced degradation, and(B) the concentrated aqueous polymer dispersion according to any of the claims 1 to 7.

10. The composition according to claim 9 wherein the amount of component B) is from 0.1 to 40% by weight based on the weight of component A).11 . The composition according to any of claims 9 to 10, which is an adhesive composition, preferably an aqueous adhesive acrylic polymer dispersion, or an aqueous adhesive polyurethane dispersion.

12. The composition according to any of claims 9 to 11 , additionally comprising a further additive.

13. The composition according to claim 12, which comprises as further additives sterically hindered amine stabilizers, UV-absorbers, phosphites, phosphonites, benzofuranones, indolinones, metal stearates, metal oxides, pigments, dyes, organophosphorus compounds, hydroxylamines, metal deactivators, nitrones, thiosynergists, peroxide scavengers, nucleating agents, fillers, reinforcing agents, plasticisers, lubricants, emulsifiers, rheology additives, catalysts, flow-control agents, optical brighteners, antistatic agents, blowing agents, biocides, slip- and leveling agents, wetting agents, dispersants, defoamers, matting agents, waxes, anti skinning additives, adhesion promoters, coalescents, rheology modifiers, sag control agents, thixotropic agents, flame retardants or mixtures thereof.

14. Use of a concentrated aqueous polymer dispersion according to any one of claims 1 to 7 as stabilizer against thermal, oxidative or light-induced degradation of organic materials, which are susceptibel to thermal, oxidative or light induced degradation.

15. Use of a stabilizer compound of formula(la), wherein o and p independently of one another are integers from 1 to 8, as stabilizer against thermal, oxidative or light-induced degradation of organic materials in combination with at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C, which prevents crystallization of the stabilizer compound (A) in the organic material, wherein the stabilizer compound of formula (I) and the stabilizer compound (B) are used in the form of the concentrated aqueous polymer dispersion according to any of the claims 1 to 7.from 1 to 8; p is 0, q is 0 and n is 3; especially a stabilizer compound of formulab2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant; or comprising a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b1) at least one stabilizer compound of formula (I), especially compound (A-1), b3) a non-ionic, cationic or anionic surfactant, and a) a polymer carrier prepared by heterophase radical polymerization of at least one ethylenically unsaturated monomer in the presence of b2) at least one stabilizer compound (B) having at least one thioether functional group and having a melting point of less than 100 °C; and b3) a non-ionic, cationic or anionic surfactant.

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