EP3997141A1 - Process of preparing allophanate- and/or thioallophanate group-containing compounds - Google Patents

Abstract

The invention relates to a process of preparing allophanate- and/or thioallophanate group-containing compounds comprising the following steps: reacting A) at least one component having at least one uretdione group with B) at least one component having at least one hydroxyl and/or thiol group, in the presence C) of at least one catalyst, containing a structural element of the general formulae (I) and/or (II), wherein R1, R2, R3, R4, R5 and R6 independently of each other represent the same or different radicals meaning saturated or unsaturated, linear or branched, aliphatic, cycloaliphatic, araliphatic or aromatic organic radicals with 1 to 18 carbon atoms that are substituted or unsubstituted and/or have heteroatoms in the chain, the radicals being capable of forming, even when combined with each other and optionally together with an additional heteroatom, rings with 3 to 8 carbon atoms that can optionally be further substituted, wherein R3, R4, R5 and R6 independently of each other also can represent hydrogen, and R7 represents hydrogen or a carboxylate anion (COO-), the at least one component A) having at least one uretdione group being polyaddition compounds A2) that can be obtained by reacting isocyanate-functional uretdione groups A1) with alcohols and/or amines that have a free isocyanate group content of less than 5 wt.% in their solvent-free form.

Description

Process for the preparation of compounds containing allophanate and / or thioallophanate groups

The present invention relates to a process for the production of compounds containing allophanate and / or thioallophanate groups, compositions containing uretdione groups and the use of these compositions for the production of polyurethane plastics or coatings. The invention also relates to coating compositions containing the compositions and substrates coated with the coating composition.

Polyaddition products containing uretdione groups are known as crosslinking components for thermally crosslinkable polyurethane (PUR) lacquer and adhesive compositions. The crosslinking principle used in these products is the thermal ring opening of the uretdione groups to form isocyanate groups and their reaction with a hydroxy-functional or amino-functional binder.

In practice, crosslinkers containing uretdione groups are used today almost exclusively for the production of split-free polyurethane (PUR) powder coatings (e.g. DE-A 2 312 391, DE-A 2 420 475, EP-A 0 045 994, EP-A 0 045 996, EP-A 0 045 998, EP-A 0 639 598 or EP-A 0 669 353). The use of polyurethanes containing uretdione groups as crosslinking components for solvent-borne or aqueous one-component systems has also already been described (e.g. WO 99/1 1690, WO 2014/053269), partly because of the comparatively low reactivity of the isocyanate groups which are internally blocked in the form of uretdione structures , which generally requires baking temperatures of at least 160 ° C in combination with polyols, such systems have so far not been able to establish themselves on the market.

There has been no lack of attempts to lower the curing temperatures of lacquer systems containing uretdione groups by using suitable catalysts. Various compounds have already been proposed for this purpose, for example the organometallic catalysts known from polyurethane chemistry, such as tin (II) acetate, tin (II) octoate, tin (II) ethyl caproate, tin (II) laurate, dibutyltin diacetate, dibutyltin dilaurate , Dibutyltin maleate (e.g. EP-A 0 045 994, EP-A 0 045 998, EP-A 0 601 079, WO 91/07452 or DE-A 2 420 475), iron (III) chloride, zinc chloride, zinc 2-ethylcaproate and molybdenum glycolate, tertiary amines, such as triethylamine, pyridine, methylpyridine, benzyldimethylamine, N, N-endoethylene piperazine, N-methylpiperidine, pentamethyldiethylenetriamine, N, N-dimethylaminocyclohexane and EP N, N'-598-A639- ) or N, N, N'-th-substituted amidines, especially bicyclic amidines, such as 1, 5-diazabicyclo [4.3.0] non-5-ene (DBN) and 1,8-diazabicyclo [5.4.0] undec-7ene ( DBU) (e.g. EP-A 0 803 524 or WO 201 1/1 15669). Of these catalysts, the bicyclic amidines mentioned allow the lowest stoving temperatures. At the same time, however, they lead to yellowing which is unacceptably high for many areas of application.

According to the teaching of EP-A 1 137 689, Lewis acid catalysts, such as the tin or zinc compounds mentioned above, are inhibited by acid groups such as carboxyl groups. They can therefore only develop their full catalytic activity in a uretdione system if the hydroxy-functional binder used is free from carboxyl groups. This can be achieved, for example, by simultaneously adding a sufficient amount of an agent which is reactive towards carboxyl groups, for example a carbodiimide or an epoxide.

In the absence of carboxyl groups or with the use of a compound which is reactive towards carboxyl groups, quaternary ammonium hydroxides and ammonium fluorides (e.g. EP-A 1 334 987), ammonium carboxylates (e.g. EP-A 1 475 399, EP-A 1 522) are also available 547), phosphonium hydroxides, alcoholates or carboxylates (e.g. WO 2005/085315) or metal hydroxides and alcoholates (e.g. EP-A 1 475 400) are suitable catalysts with which the curing temperature of uretdione systems can be significantly reduced .

In principle, a uretdione structure can react in two ways during curing, the complete splitting into two isocyanate groups, which subsequently form urethane groups with two hydroxyl groups of the polyol, or a ring opening only on one side with only one hydroxyl group of the polyol to form an allophanate structure. As a rule, both reactions take place side by side in catalyzed uretdione systems, the preference between the two reaction products shifting with the curing conditions, in particular the temperature. At the same time, the trimerization of isocyanate groups to give isocyanurate structures can often be observed to varying degrees.

This not clearly defined curing behavior of the uretdiones makes it difficult in practice to set the optimal stoichiometry between uretdione crosslinker and polyol and contributes to the low spread of low temperature crosslinking uretdione systems.

The object of the present invention was therefore to provide new catalysts for lowering the hardening temperature of uretdione systems, which lead to the most complete conversion of the uretdione structures and thereby provide a fixed ratio of the reaction products regardless of the hardening temperature.

It was possible to achieve this object by providing the compositions containing catalyzed uretdione groups described in more detail below. The present invention is based on the surprising observation that special salts with an imidazolium or dihydroimidazolium structure are highly effective catalysts for the reaction of uretdiones with alcohols and / or thiols, with only allophanate, thioallophanate and optionally isocyanurate structures in a fixed ratio.

Such catalysts are known and have also been used in polyurethane chemistry in the past. WO 201 1/061314 also describes imidazolium salts as a possible alternative to toxicologically questionable tin catalysts, such as. B. dibutyltin dilaurate (DBTL), for the reaction of isocyanates with polyols in polyurethane synthesis. Although this publication includes a blanket list of possible starting polyisocyanates for urethanization including those with a uretdione structure, there is no mention of the particular suitability of imidazolium and dihydroimidazolium compounds as catalysts for selective uretdione cleavage with the formation of allophanate or Thioallophanate structures.

Disclosed is a process for the preparation of compounds containing allophanate and / or thioallophanate groups comprising reaction of

A) at least one component containing at least one uretdione group

B) at least one component having at least one hydroxyl and / or thiol group in the presence

C) at least one catalyst containing a structural element of the general formulas (I) and / or (II)

in which

R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ independently represent identical or different radicals which are saturated or unsaturated, linear or branched, aliphatic, cycloaliphatic, araliphatic or aromatic organic radicals having 1 to 18 carbon atoms , which are substituted or unsubstituted and / or have heteroatoms in the chain, the radicals also in combination with one another, optionally together with another Can form heteroatom rings with 3 to 8 carbon atoms, which can optionally be further substituted, wherein

R ³ , R ⁴ , R ⁵ and R ^{6 can} independently also represent hydrogen, and

R ^{7 represents} hydrogen or a carboxylate anion (COO).

The present invention relates to a process for the preparation of compounds containing allophanate and / or thioallophanate groups, comprising the reaction of

A) at least one component containing at least one uretdione group

B) at least one component having at least one hydroxyl and / or thiol group in the presence

C) at least one catalyst containing a structural element of the general formulas (I) and / or (II)

in which

R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ independently represent identical or different radicals which are saturated or unsaturated, linear or branched, aliphatic, cycloaliphatic, araliphatic or aromatic organic radicals having 1 to 18 carbon atoms , which are substituted or unsubstituted and / or have heteroatoms in the chain, the radicals also in combination with one another, optionally together with another heteroatom, can form rings with 3 to 8 carbon atoms, which can optionally be further substituted, where

R ³ , R ⁴ , R ⁵ and R ^{6 can} independently also represent hydrogen, and

R ^{7 stands} for hydrogen or a carboxylate anion (COO), with the at least one component A) having at least one uretdione group being polyaddition compounds A2) obtainable by reacting isocyanate-functional uretdione groups with compounds A1) with alcohols and / or amines, which in solvent-free form have a content of free isocyanate groups of less than 5% by weight. According to the invention, the references to “comprising”, “containing” etc. preferably mean “essentially consisting of” and very particularly preferably “consisting of”. The further embodiments mentioned in the patent claims and in the description can be combined as desired, unless the context clearly indicates the opposite.

The uretdione-containing component A) is any desired, optionally isocyanate-functional uretdione-containing compounds A1), as are obtainable by methods known per se, for example by oligomerizing monomeric isocyanates, and / or by reacting compounds A1) containing isocyanate-functional uretdione groups Polyaddition compounds A2) obtainable from alcohols and / or amines.

In the process according to the invention, the at least one component A) containing at least one uretdione group is a polyaddition compound A2) obtainable by reacting compounds A1) containing isocyanate-functional uretdione groups with alcohols and / or amines.

Suitable isocyanates for the preparation of the uretdione-containing compounds A1) are any, in various ways, for example by phosgenation in the liquid or gas phase or by phosgene-free route, such as. B. by thermal urethane cleavage, accessible mono-, di- and triisocyanates with aliphatically, cycloaliphatically, araliphatically and / or aromatically bound isocyanate groups.

Preferred monoisocyanates are those of the molecular weight range 99 to 300, such as. B. n-butyl isocyanate, n-amyl isocyanate, n-hexyl isocyanate, n-heptyl isocyanate, n-octyl isocyanate, undecyl isocyanate, dodecyl isocyanate, tetradecyl isocyanate, cetyl isocyanate, stearyl isocyanate, cyclopentyl isocyanate, cyclohexyl isocyanate, 3- or 4-methylcyclohexyl isocyanate, phenyl isocyanate or naphyl isocyanate, phenyl isocyanate, or naphthyl isocyanate, phenyl isocyanate, phenyl isocyanate, phenyl isocyanate, phenyl isocyanate, phenyl isocyanate, 3- and 4- methyl-cyclohexyl isocyanate, naphthyl isocyanate, n-heptyl isocyanate, n-octyl isocyanate, phenyl isocyanate, phenyl isocyanate, 3- and 4- methylcyclohexyl isocyanate, phenyl isocyanate, phenyl isocyanate, phenyl isocyanate, phenyl isocyanate, phenyl isocyanate, n-heptyl isocyanate, n-octyl isocyanate.

Preferred diisocyanates are those of the molecular weight range 140 to 400, such as 1,4-diisocyanatobutane, 1,5-diisocyanatopentane (pentamethylene diisocyanate, PDI),

1,6-Diisocyanatohexane (hexamethylene diisocyanate, HDI), 2-methyl-1,5-diisocyanatopentane, 1,5-diisocyanato-2,2-dimethylpentane, 2,2,4- and 2,4,4-trimethyl -

1, 6-diisocyanatohexane, 1, 10-diisocyanatodecane, 1, 3- and 1, 4-diisocyanatocyclohexane, 1, 3- and 1, 4-bis- (isocyanatomethyl) -cyclohexane, 1, 3-diisocyanato-2 (4) methylcyclohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI), 2,4'- and 4,4'-diisocyanatodicyclohexylmethane (H12-MDI), 4,4'-diisocyanato-3 , 3'-dimethyldicyclohexyl methane, 4,4'-diisocyanato-3,3 ', 5,5'-tetramethyldicyclohexyl methane, 4,4'-diisocyanato-1, 1' -bi (cyclohexyl), 4,4'-diisocyanato-3 , 3'-dimethyl-1, 1 '-bi (cyclohexyl), 4,4'-diisocyanato-2,2', 5,5 ^, -tetra-methyl-1, 1 '-bi (cyclohexyl), 1, 8 -Diisocyanato-p-menthane, 1,3-diisocyanatoadamantane, 1,3-dimethyl-5,7-diisocyanatoadamantane, 1-isocyanato-1-methyl-4 (3) isocyanato-methylcyclohexane, bis- (isocyanatomethyl) -norbornane (NBDI), 1, 3- and 1, 4-bis (isocyanatomethyl) benzene (xylylene diisocyanate, XDI), 1, 3- and 1, 4-bis (2- isocyanatopropan-2-yl) benzene (tetramethylxylylene diisocyanate, TMXDI), 1, 3- bis (isocyanatomethyl) - 4-methylbenzene, 1,3-bis (isocyanatomethyl) -4-ethylbenzene, 1,3-bis (isocyanatomethyl) -5-methylbenzene, 1,3-bis (isocyanatomethyl) -4,5-dimethylbenzene,

1,4-bis (isocyanatomethyl) -2,5-dimethylbenzene, 1,4-bis (isocyanatomethyl) -2, 3,5,6-tetramethylbenzene, 1,3-bis (isocyanatomethyl) -5-tert-butylbenzene, 1, 3-

Bis (isocyanatomethyl) -4-chlorobenzene, 1,3-bis (isocyanatomethyl) -4,5-dichlorobenzene, 1,3-bis (isocyanatomethyl) -2,4,5,6-tetrachlorobenzene, 1,4-bis (isocyanatomethyl ) -2, 3,5,6-tetrachlorobenzene, 1,4-bis (isocyanatomethyl) -2,3,5,6-tetrabromobenzene, 1,4-bis (2-isocyanatoethyl) benzene and 1,4-bis (isocyanatomethyl) ) naphthalene, 1, 2-, 1, 3- and 1, 4- diisocyanatobenzene (phenylene diisocyanate), 2,4- and 2,6-diisocyanatotoluene (tolylene diisocyanate, TDI), 2,3,5,6-tetramethyl-1, 4-diisocyanatobenzene, the isomeric diethylphenylene diisocyanates, diisopropylphenylene diisocyanates,

Diisododecylphenylene diisocyanates and biphenyl diisocyanates, 3,3'-dimethoxybiphenyl- 4,4'-diisocyanate, 2,2‘-, 2,4'- and 4,4'-diisocyanatodiphenylmethane (MDI), 3,3'-

Dimethyldiphenylmethane-4,4'-diisocyanate, 4,4'-diisocyanatodiphenylethane, 1,5-diisocyanatonaphthalene (naphthylene diisocyanate, NDI), diphenyl ether diisocyanate, ethylene glycol diphenyl ether diisocyanate, diethylene glycol diphenyl ether diisocyanate, tylenol diphenyl ether diisocyanate, benzene-2,4-glycol ether diisocyanate, benzene-2,4-glycol ether diisocyanate, 1,3-propylene glycol diisocyanate, 2,4-benzene glycol diisocyanate. Triisocyanatotoluene, trimethylbenzene triisocyanate, diphenylmethane-2,4,4'-triisocyanate, 3-methyldiphenylmethane-4,6,4'-triisocyanate, the isomeric naphthalene triisocyanates and methylnaphthalene diisocyanates, triphenylmethane triisocyanate or 2,4-diisocyanato-1 - [(5- isocyanato-2-methylphenyl) methyl] benzene.

Further, likewise suitable diisocyanates can also be found, for example, in Justus Liebigs Annalen der Chemie Volume 562 (1949) pp. 75-136.

A particularly suitable triisocyanate is 4-isocyanatomethyl-1,8-octane diisocyanate (triisocyanatononane; TIN).

To prepare the compounds A1) containing uretdione groups, mixtures of at least two such mono-, di- and / or triisocyanates can also be used.

To prepare the compounds A1) containing uretdione groups, preference is given to using monomeric diisocyanates.

The use of PDI, HDI, IPDI, XDI, NBDI and / or H12-MDI is particularly preferred. The compounds A1) containing uretdione groups can be prepared by various methods which are generally based on the customary processes known from the literature for the oligomerization of simple diisocyanates, as described, for example, in J. Prakt. Chem. 336 (1994) 185-200, DE-A 16 70 666, DE-A 19 54 093, DE-A 24 14 413, DE-A 24 52 532, DE-A 26 41 380, DE-A 37 00 209, DE-A 39 00 053, DE-A 39 28 503, EP-A 336 205, EP-A 339 396 and EP-A 798 299 are described.

The compounds A1) containing uretdione groups can be free of isocyanate groups when monoisocyanates are used exclusively or in part. For their preparation, however, at least additional di- and / or triisocyanates are used in such amounts that compounds A1) containing uretdione groups are obtained which have an average NCO functionality of at least 1.6, preferably 1.8 to 3.5 , particularly preferably from 1.9 to 3.2, very particularly preferably from 2.0 to 2.7.

With average NCO functionalities of> 2.0, these compounds A1) containing isocyanate-functional uretdione groups contain not only linear, difunctional uretdione structures, but also further, at least trifunctional polyisocyanate molecules. These higher functional components of the compounds A1) are in particular the known secondary products of diisocyanates with an isocyanurate, allophanate, biuret, urethane and / or iminooxadiazinedione structure.

The compounds A1) containing uretdione groups are generally freed from the unreacted excess of monomers immediately after their preparation as described above by modifying simple monomeric mono-, di- and / or triisocyanates by known methods, for example by thin-film distillation or extraction. They therefore generally have residual amounts of monomeric diisocyanates of less than 5% by weight, preferably less than 2% by weight, particularly preferably less than 1% by weight.

Regardless of the production process selected, the compounds A1) containing uretdione groups generally have a uretdione structure content (calculated as C2N2O2, molecular weight = 84) of 10 to 25% by weight, preferably 12 to 23% by weight, particularly preferably 14 to 20% by weight.

In a further preferred embodiment, component A1) is compounds containing uretdione groups based on PDI, HDI, IPDI, XDI, NBDI and / or H12-MDI, which preferably have an average NCO functionality of at least 1.6 and particularly preferably have a content of uretdione structures (calculated as C2N2O2, molecular weight = 84) of 10 to 25% by weight. Also suitable as uretdione-containing component A) of the compositions according to the invention are polyaddition compounds A2), as can be obtained by reacting at least some of the free isocyanate groups of the above-described isocyanate-functional uretdione-containing compounds A1) with alcohols and / or amines.

Suitable alcohols for the preparation of the polyaddition compounds A2) are, for example, simple aliphatic or cycloaliphatic monoalcohols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, the isomeric pentanols, hexanols, octanols and nonanols, n- Decanol, n-dodecanol, n-tetradecanol, n-hexadecanol, n-octadecanol, cyclohexanol, the isomeric methylcyclohexanols and hydroxymethylcyclohexane, ether alcohols such as 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-butoxyethanol, diethylene glycol,

Diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, 3-methoxy-1-butanol and glycerol-1,3-diethyl ether, ester alcohols such as hydroxyethyl acetate, butyl glycolate, ethyl lactate, glycerol diacetate or those that can be obtained by reacting the mentioned monoalcohols, such as ethers, with lactones can be obtained by reacting the monoalcohols mentioned with alkylene oxides, in particular ethylene oxide and / or propylene oxide.

Likewise suitable alcohols for the preparation of the polyaddition compounds A2) are any at least difunctional polyols in the molecular weight range 62 to 22,000, preferably those which have an average functionality of 2 to 6 and a number average molecular weight of 62 to 18,000, particularly preferably an average functionality of 2 to 4 and a number average molecular weight of 90 to 12,000.

Suitable polyols for producing the polyaddition compounds A2) are, for example, simple polyhydric alcohols having 2 to 14, preferably 4 to 10 carbon atoms, such as. B. 1, 2-ethanediol, 1, 2- and 1, 3-propanediol, the isomeric butanediols, pentanediols, hexanediols, heptanediols and octanediols, 1, 10-decanediol, 1, 12-dodecanediol, 1, 2- and 1, 4- cyclohexanediol, 1,4-cyclohexanedimethanol, 1,4-bis (2-hydroxyethoxy) benzene, 2,2-bis- (4-hydroxyphenyl) propane (bisphenol A), 2,2-bis (4- hydroxycyclohexyl) propane (perhydro bisphenol), 1, 2,3-propanetriol, 1, 2,4-butanetriol, 1, 1, 1-trimethylolethane, 1, 2,6-hexanetriol, 1, 1, 1 -trimethylolpropane ( TMP), bis (2-hydroxyethyl) hydroquinone, 1, 2,4- and 1, 3,5-trihydroxycyclohexane, 1, 3,5-tris (2-hydroxyethyl) isocyanurate, 3 (4), 8 ( 9) -to-

(hydroxymethyl) -tricyclo- [5.2.1 .0 ²⁶ ] decane, di-trimethylolpropane, 2,2-bis (hydroxymethyl) -1, 3-propanediol (pentaerythritol), 2,2,6,6-tetrakis (hydroxymethyl) -4-oxa-heptane-1,7-diol (dipentaerythritol), mannitol or sorbitol, low molecular weight ether alcohols, such as. B. Diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol or

Dibutylene glycol or low molecular weight ester alcohols, such as. B. neopentyl glycol hydroxypivalate.

Suitable polyols for preparing the polyaddition compounds A2) are also the customary polymeric polyether polyols, polyester polyols, polycarbonate polyols and / or polyacrylate polyols known from polyurethane chemistry, which usually have a number average molecular weight of 200 to 22,000, preferably 250 to 18,000, particularly preferably 250 to 12,000 . A broad overview of suitable polymeric polyols for preparing the polyaddition compounds A2) can be found, for example, in N. Adam et al. Polyurethanes. In: Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH Verlag GmbH & Co. KgaA; 2005. URL: https://doi.org/10.1002/14356007.a21_665.pub2. Suitable polyether polyols are, for example, those in DE 26 22 951 B, column 6, line 65 to column 7, line 26, EP-A 0 978 523 page 4, line 45 to page 5, line 14 or WO 201 1 / 069966, page 4, line 20 to page 5, line 23, provided that they correspond to the information given above with regard to functionality and molecular weight. Particularly preferred polyether polyols are adducts of ethylene oxide and / or propylene oxide with 1,2-propanediol, 1,3-propanediol, glycerol, trimethylolpropane, ethylenediamine and / or pentaerythritol or those according to Angew. Chem. 72, 927 (1960) (https://doi.org/10.1002/ange.19600722402) polytetramethylene ether glycols obtainable by polymerization of tetrahydrofuran with number average molecular weights of 400 g / mol to 4000 g / mol.

Suitable polyester polyols are, for example, those of the type mentioned in EP-A 0 978 523, page 5, lines 17 to 47 or EP-A 0 659 792, page 6, lines 32 to 45, provided they comply with the information given above with regard to functionality and Molecular weight correspond. Particularly preferred polyester polyols are condensation products of polyhydric alcohols, such as. B. 1,2-ethanediol, 1,2-propanediol, diethylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentylglycol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediol, perhydrobisphenol, 1, 1, 1 - Trimethylolpropane, 1,2,3-propanetriol, pentaerythritol and / or sorbitol, with insufficient amounts of polybasic carboxylic acids or carboxylic acid anhydrides, such as. B. succinic acid, adipic acid, sebacic acid, dodecanedioic acid, glutaric anhydride, maleic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, trimellitic acid, hexahydrophthalic anhydride and / or tetrahydrophthalic anhydride, or those such as are known in the art from lactones. B. e-caprolactone, and simple polyhydric alcohols, such as. B. those mentioned above, are available as starter molecules with ring opening. Suitable polycarbonate polyols are in particular the known reaction products of dihydric alcohols, for example those as mentioned above in the list of polyhydric alcohols by way of example, with diaryl carbonates, such as. B. diphenyl carbonate, dimethyl carbonate or phosgene. Polycarbonate polyols which are also suitable are those which, in addition to carbonate structures, also contain ester groups. These are, in particular, the polyester carbonate diols known per se, such as those obtained, for example, according to the teaching of DE-AS 1 770 245 by reacting dihydric alcohols with lactones, such as, in particular, s-caprolactone, and then reacting the resulting polyester diols with diphenyl or dimethyl carbonate can be obtained.

Suitable polyacrylate polyols are, for example, those of the type mentioned in WO 201 1/124710 page 10, line 32 to page 13, line 18, provided that they correspond to the information given above with regard to functionality and molecular weight. Particularly preferred polyacrylate polyols are polymers or copolymers of hydroxyalkyl esters of acrylic acid or methacrylic acid, such as. B. hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate or hydroxybutyl (meth) acrylate, optionally together with acrylic acid alkyl esters and / or methacrylic acid alkyl esters, such as. B. methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,

Cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, lauryl (meth) acrylate, styrene or other copolymerizable olefinically unsaturated monomers, such as. B. acrylic acid, methacrylic acid or maleic acid dimethyl ester.

Suitable polyols are, for example, the known, by reaction of simple glycols, such as. B. diethylene glycol, triethylene glycol, 4,4'-dioxethoxy-diphenyl- dimethylmethane (adduct of 2 mol of ethylene oxide with bisphenol A) or hexanediol, polyacetal polyols obtainable with formaldehyde or by polycondensation of cyclic acetals, such as. B. trioxane, manufactured polyacetals.

Further suitable polyols for preparing the polyaddition compounds A2) are, for example, those described in EP-A 0 689 556 and EP-A 0 937 1 10, e.g. B. by reacting epoxidized fatty acid esters with aliphatic or aromatic polyols with epoxy ring opening available special polyols as well as hydroxyl-containing polybutadienes.

Suitable amines for preparing the polyaddition compounds A2) are, for example, simple aliphatic or cycloaliphatic monoamines, such as. B. methylamine, ethylamine, n-propylamine, isopropylamine, the isomeric butylamine, pentylamine, hexylamine and octylamine, n-dodecylamine, n-tetradecylamine, n-hexadecylamine, n- Octadecylamine, cyclohexylamine, the isomeric methylcyclohexylamine and aminomethylcyclohexane, secondary monoamines such as dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, diisobutylamine, bis (2-ethylhexyl) amine, N-methyl- and N-ethyl-cyclohexylamine and dicyclohexylamine.

Suitable amines are also any aliphatic and cycloaliphatic amines with at least two primary and / or secondary bonded amino groups, such as. B. 1,2-diaminoethane, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 1,2-diamino-2-methylpropane, 1,5-diaminopentane, 1,3-diamino-2, 2-dimethylpropane, 1,6-diaminohexane,

1, 5-diamino-2-methylpentane, 1, 6-diamino-2,2,4-trimethylhexane, 1, 6-diamino-2,4,4-trimethylhexane, 1, 7-diaminoheptane, 1, 8-diaminooctane, 2,5-diamino-2,5-dimethylhexane, 1, 9-diaminononane, 2-methyl-1, 8-diaminooctane, 1, 10-diaminodecane, 1, 1 1 -

Diaminoundecane, 1, 12-diaminododecane, 1, 2-diaminocyclopentane, 1, 2-

Diaminocyclohexane, 1-amino-3,3,5-trimethyl-5-aminomethylcyclohexane (isophoronediamine, IPDA), 3 (4) -aminomethyl-1-methylcyclohexylamine, 1,3-diamino-2- and / or -4-methylcyclohexane, Isopropyl-2,4- and / or 2,6-diaminocyclohexane, 1,3-bis (aminomethyl) -cyclohexane, 1,8-p-diaminomenthan, bis (4-aminocyclohexyl) -methane, bis (4-amino-3 - methylcyclohexyl) methane, bis (4-amino-3,5-dimethylcyclohexyl) methane, bis (4-amino-

2.3.5-trimethylcyclohexyl) methane, 1, 1-bis (4-aminocyclohexyl) -propane, 2,2-bis (4-aminocyclohexyl) -propane, 1, 1-bis (4-aminocyclohexyl) -ethane, 1, 1-bis (4-aminocyclohexyl) -butane, 2,2-bis (4-aminocyclohexyl) -butane, 1,1-bis (4-amino-3-methylcyclohexyl) -ethane, 2,2-bis (4-amino -3-methylcyclohexyl) propane, 1, 1 -bis (4-amino-3,5-dimethylcyclohexyl) ethane, 2,2-bis (4-amino-3,5-dimethylcyclohexyl) propane, 2,2- Bis (4-amino-3,5-dimethylcyclohexyl) butane, 2,4-diaminodicyclohexylmethane, 4-aminocyclohexyl-4-amino-3-methylcyclohexyl-methane, 4-amino-3,5-dimethylcyclohexyl-4-amino-3 -methylcyclohexyl-methane and 2- (4- aminocyclohexyl) -2- (4-amino-3-methylcyclohexyl) -methane, m-xylylenediamine,

Methyliminobispropylamine, iminobispropylamine, bis (6-aminohexyl) -amine, N, N-bis (3-aminopropyl) -ethylenediamine, 4-aminomethyl-1,8-octanediamine, bis (aminopropyl) piperazine, aminoethylpiperazine, diethylenetriamine, dipropylenetriamine, triethylenetetriamine Tetraethylene pentamine, pentaethylene hexamine, heptaethylene octamine.

Suitable amines are also amino-functional polyalkylene glycols, such as. B. 1,2-bis (aminoethoxy) -ethane, 1,1-diamino-3,6,9-trioxaundecane, 1,13-diamino-4,7,10-trioxatride-can and in particular those under the trade name Jeffamine ^® from Huntsman Corp. Commercially marketed amine-functionalized polyalkylene glycols with number average molecular weights up to 5000, preferably up to 2000, particularly preferably up to 1000. If necessary, sterically hindered aliphatic diamines with two secondary amino groups for the preparation of the polyaddition compounds A2) can be used, such as. B. the reaction products known from EP-A 0 403 921 of aliphatic and / or cycloaliphatic diamines with maleic or fumaric acid esters, the bisadduct of acrylonitrile with isophoronediamine obtainable according to the teaching of EP-A 1 767 559 or the, for example, in DE-A 19 701 835 described hydrogenation products of aliphatic and / or cycloaliphatic diamines and ketones, such as. B. Diisopropyl ketone, accessible Schiff bases.

Other suitable polyamines are also the polyamidoamines, polyimines and / or polyvinylamines known as crosslinking components for epoxy resins.

To prepare the polyaddition compounds A2), amino alcohols, such as. B. 2-aminoethanol, the isomeric aminopropanols and butanols, 3-amino-1,2-propanediol and 1,3-diamino-2-propanol, are suitable.

In the preparation of the polyaddition compounds A2) from the compounds A1) containing isocyanate-functional uretdione groups, the alcohols and / or amines mentioned are used either individually or as mixtures of at least two such alcohols and / or amines.

The polyaddition compound A2) containing uretdione groups can be prepared by various methods, for example the processes known from the literature for the preparation of polyurethane compositions, as described, for example, in WO 99/1 1690 and WO 201 1/1 15669.

In addition to the compounds A1) containing isocyanate-functional uretdione groups, further monomeric isocyanates of the above-mentioned type and / or oligomeric polyisocyanates, preferably those with an isocyanurate, biuret, iminooxadazinedione, allophanate and / or urethane structure, can be used in an amount of up to 30% by weight, based on the total weight of all reactants (including the compounds A1 containing isocyanate-functional uretdione groups), alcohols and / or amines) can also be used.

The reaction is preferably carried out in compliance with an equivalent ratio of isocyanate groups to isocyanate-reactive groups of 2: 1 to 0.5: 1, preferably from 1.5: 1 to 0.7: 1, particularly preferably from 1: 1 to 0.9 : 1 .

In a further preferred embodiment, the polyaddition compounds A2) are compounds which are obtained by reacting isocyanate-functional compounds A1) containing uretdione groups with at least difunctional polyols of the molecular weight range 62 to 22,000 and optionally monoalcohols are prepared while maintaining an equivalent ratio of isocyanate groups to isocyanate-reactive groups of 2: 1 to 0.5: 1.

The reaction can be carried out without a solvent or in a suitable solvent which is inert towards isocyanate groups.

Suitable solvents for the preparation of the polyaddition compounds A2) are in particular those which are inert towards the isocyanate groups of the compound A1), for example the known customary aprotic paint solvents such as. B. ethyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, amyl acetate, 2-ethylhexyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, 1-methoxypropyl-2-acetate, 3-methoxy-n-butyl acetate, 4-methoxy-n-butyl acetate, 4-methoxy-n-butyl acetate, 4- methyl-2-pentanone, diisobutyl ketone cyclohexanone, cyclohexane, toluene, xylene, chlorobenzene, dichlorobenzene, white spirit, more highly substituted aromatics such as, for example, under the names Solvent naphtha, Solvesso ^®, Isopar ^®, Nappar ^® (German EXXON CHEMICAL GmbH, Cologne , DE) and Shellsol ^® (Deutsche Shell Chemie GmbH, Eschborn, DE) are commercially available, but also solvents such as propylene glycol diacetate, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, diethylene glycol ethyl and butyl ether acetate, ethyl ethoxypropionate, propylene carbonate, N-methylpyrrolidone and Tetrahydrofuran or any mixtures of such solvents.

The reaction of the isocyanate-functional uretdione group-containing compounds A1) with the alcohols and / or amines to form the uretdione group-containing polyaddition compounds A2) can take place without catalysis. However, conventional catalysts known from polyurethane chemistry can also be used to accelerate the reaction. Examples are tert here. Amines such as B. triethylamine, tributylamine, dimethylbenzylamine, diethylbenzylamine, pyridine, methylpyridine, dicyclohexylmethylamine, dimethylcyclohexylamine, N, N, N ', N'-

Tetramethyldiaminodiethylether, bis (dimethylaminopropyl) urea, N-methyl- or N-ethylmorpholine, N-cocomorpholine, N-cyclohexylmorpholine, N, N, N ', N'-

Tetramethylethylenediamine, N, N, N ', N'-tetramethyl-1, 3-butanediamine, N, N, N', N'-tetramethyl-1, 6-hexanediamine, pentamethyldiethylenetriamine, N-methylpiperidine, N-dimethylaminoethylpiperidine, N, N'-dimethylpiperazine, N-methyl-N'-dimethylaminopiperazine, 1,8-diazabicyclo (5.4.0) undec-7-en, 1,2-dimethylimidazole, 2-methylimidazole, N, N-dimethylimidazole-ß- phenylethylamine, 1,4-diazabicyclo- (2,2,2) -octane, bis- (N, N-dimethylaminoethyl) adipate; Alkanolamine compounds, such as. B. triethanolamine, triisopropanolamine, N-methyl- and N-ethyl-diethanolamine, dimethylaminoethanol, 2- (N, N- Dimethylaminoethoxy) ethanol, N, N ', N "-Tris- (dialkylaminoalkyl) hexahydrotriazines, for example N, N', N" -Tris- (dimethylaminopropyl) -s-hexahydrotriazine and / or

Bis (dimethylaminoethyl) ether; Metal salts such as B. inorganic and / or organic compounds of iron, lead, bismuth, zinc and / or tin in the usual oxidation states of the metal, for example iron (II) chloride, iron (III) chloride, bismuth (III) acetate, bismuth (III) -2-ethylhexanoate, bismuth (III) octoate, bismuth (III) neodecanoate, zinc chloride, zinc 2-ethyl caproate, tin (II) octoate, tin (II) ethyl caproate, tin (II) palmitate , Dibutyltin (IV) dilaurate (DBTL), dibutyldilauryltin mercaptide, or lead octoate; Amidines, e.g. B. 2,3-dimethyl-3,4,5,6-tetrahydropyrimidine; Tetraalkylammonium hydroxides, such as. B. tetramethylammonium hydroxide; Alkali hydroxides, such as. B. sodium hydroxide and alkali metal alcoholates, such as. B. sodium methylate and potassium isopropylate, and alkali salts of long-chain fatty acids with 10 to 20 carbon atoms and optionally pendant OH groups.

Preferred catalysts are tert. Amines, bismuth and tin compounds of the type mentioned.

Regardless of how they are prepared, the polyaddition compounds A2) containing uretdione groups in solvent-free form have a free isocyanate group content of less than 5% by weight, preferably less than 2% by weight and particularly preferably less than 1, in the process according to the invention % By weight. Polyaddition compounds A2) free of isocyanate groups are very particularly preferred.

In the process according to the invention, component A) having uretdione groups is combined with a component B) having at least one hydroxyl and / or at least one thiol group as a reactant.

The component B) is, for example, the compounds mentioned above as suitable alcohols for the preparation of the polyaddition compound A2), in particular at least difunctional polyols of the molecular weight range 62 to 22,000.

Suitable hydroxy-functional components B) are preferably the simple polyhydric alcohols with 2 to 14 carbon atoms mentioned there, low molecular weight ether and ester alcohols and the customary polymeric polyether polyols, polyester polyols, polycarbonate polyols and / or polyacrylate polyols known from polyurethane chemistry.

Suitable components B) are also compounds which have at least one thiol group per molecule. Suitable thiol-functional components B) are preferably polythiols, for example simple alkanethiols, such as. B. Methanedithiol, 1,2-ethanedithiol, 1,1-propanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 2,2-propanedithiol, 1,4-butanedithiol, 2,3-butanedithiol, 1,5 Pentanedithiol, 1,6-hexanedithiol, 1,2,3-propanedithiol, 1,1-cyclohexanedithiol, 1,2-cyclohexanedithiol, 2,2-dimethylpropane-1,3-dithiol, 3,4-dimethoxybutane-1,2 dithiol or 2-methylcyclohexane-2,3-dithiol, thioether groups containing polythiols, such as. B. 2,4-dimercaptomethyl-1, 5-dimercapto-3-thiapentane, 4-mercaptomethyl-1, 8-dimercapto-3,6-dithiaoctane, 4,8-dimercaptomethyl-1, 1 1 -dimercapto-3,6 , 9-trithiaundecane, 4,7-dimercaptomethyl-1, 1 1 -dimer-capto-3,6,9-trithiaundecane, 5,7-dimercaptomethyl-1, 1 1 -dimercapto-3,6,9-trithiaundecane, 5 , 6-bis- (mercaptoethylthio) -1, 10-dimercapto-3,8-dithiadecane, 4,5-bis- (mercaptoethylthio) -1, 10-dimercapto-3,8-dithiadecane,

Tetrakis (mercaptomethyl) methane, 1, 1, 3,3-tetrakis (mercaptomethylthio) propane, 1, 1, 5,5-tetrakis (mercaptomethylthio) -3-thiapentane, 1, 1, 6,6-tetrakis (mercaptomethylthio) - 3,4-dithiahexane, 2-mercaptoethylthio-1, 3-dimercaptopropane, 2,3-bis (mercaptoethylthio) -1-mercaptopropane, 2,2-bis (mercaptomethyl) -1, 3-dimercaptopropane, bis-

(mercaptomethyl) sulfide, bis (mercaptomethyl) disulfide, bis (mercaptoethyl) sulfide, bis (mercapto-ethyl) disulfide, bis (mercaptopropyl) sulfide, bis (mercaptopropyl) disulfide, bis (mercaptomethyl-thio) methane, tris (mercaptomethylthio) methane ,

Bis (mercaptoethylthio) methane, T ris (mercapto-ethylthio) methane,

Bis (mercaptopropylthio) methane, 1, 2-bis (mercaptomethylthio) ethane, 1, 2-bis-

(mercaptoethylthio) ethane, 2-mercaptoethylthio) ethane, 1, 3-bis (mercaptomethylthio) propane, 1, 3-bis (mercaptopropylthio) propane, 1, 2,3-Tris (mercaptomethylthio) propane, 1, 2,3- T ris (mercapto-ethylthio) propane, 1, 2,3-T ris (mercaptopropylthio) propane,

Tetrakis (mercaptomethylthio) methane, tetrakis (mercaptoethylthiomethyl) methane,

Tetrakis (mercaptopropylthiomethyl) methane, 2,5-dimercapto-1,4-dithiane, 2,5-

Bis (mercaptomethyl) -1, 4-dithiane and its oligomers obtainable according to JP-A 071 18263, 1,5-bis (mercaptopropyl) -1, 4-dithiane, 1,5-bis (2-mercaptoethylthiomethyl) -1, 4 - dithiane, 2-mercaptomethyl-6-mercapto-1, 4-dithiacycloheptane, 2,4,6-trimercapto-1, 3,5-trithiane, 2,4,6-trimercaptomethyl-1, 3,5-trithiane or 2 - (3-bis (mercaptomethyl) -2-thiapropyl) -1, 3-dithiolane, polyester thiols, such as. B. Ethylene glycol bis (2-mercaptoacetate), ethylene glycol bis (3-mercaptopropionate), diethylene glycol (2-mercaptoacetate),

Diethylene glycol (3-mercaptopropionate), 2,3-dimercapto-1-propanol (3-mercaptopropionate), 3-mercapto-1, 2-propanediol-bis (2-mercaptoacetate), 3-mercapto-1, 2-propanediol-bis (3-mercaptopropionate), trimethylolpropane-tris (2-mercaptoacetate), trimethylolpropane-tris (3-mercaptopropionate), trimethylolethane-tris (2-mercaptoacetate), trimethylolethane-tris (3-mercaptopropionate), pentaerythritol-tetrakis 2-mercaptoacetate), pentaerythritol tetrakis (3-mercaptopropionate), glycerine tris (2-mercaptoacetate), glycerine tris (3-mercaptopropionate), 1,4-Cyclohexanediol bis (2-mercaptoacetate), 1,4-Cyclohexanediol bis (3-mercaptopropionate), hydroxymethyl sulfide bis (2-mercaptoacetate), hydroxymethyl sulfide bis (3-mercaptopropionate), hydroxyethyl sulfide ( 2-mercaptoacetate), hydroxyethyl sulfide (3-mercaptopropionate), hydroxymethyl disulfide (2-mercaptoacetate), hydroxymethyl disulfide (3-mercaptopropionate), (2-mercaptoethyl ester) thioglycolate or bis (2-mercaptoethyl ester jthiodipropionate and aromatic compounds such as 1, e.g. - dimercaptobenzene, 1,3-dimercaptobenzene, 1,4-dimercaptobenzene, 1,2-bis (mercaptomethyl) benzene, 1,4-bis (mercaptomethyl) benzene, 1, 2-

Bis (mercaptoethyl) benzene, 1,4-bis (mercaptoethyl) benzene, 1,2,3-trimercaptobenzene, 1,2,4-trimercaptobenzene, 1,3,5-trimercaptobenzene, 1,2,3-tris- (mercaptomethyl ) benzene, 1, 2,4- Tris (mercaptomethyl) benzene, 1, 3,5-Tris (mercaptomethyl) benzene, 1, 2,3-

T ris (mercaptoethyl) benzene, 1, 3,5-T ris (mercaptoethyl) benzene, 1, 2,4-T ris (mercaptoethyl) benzene, 2,5-toluene dithiol, 3,4-toluene dithiol, 1, 4-naphthalenedithiol, 1,5-naphthalenedithiol, 2,6-naphthalenedithiol, 2,7-naphthalenedithiol, 1,2,3,4-tetramercaptobenzene, 1,2,3,5-tetramercaptobenzene, 1,2,4, 5-tetramercaptobenzene, 1, 2,3,4-

T etrakis (mercaptomethyl) benzene, 1, 2,3,5-T etrakis (mercaptomethyl) benzene, 1, 2,4,5-tetrakis (mercaptomethyl) benzene, 1, 2,3,4-tetrakis (mercaptoethyl) benzene , 1, 2,3,5-

Tetrakis (mercaptoethyl) benzene, 1, 2,4,5-tetrakis (mercaptoethyl) benzene, 2,2'-

Dimercaptobiphenyl or 4,4'-dimercaptobiphenyl.

Particularly preferred thio-functional components B) are polyether and polyester thiols of the type mentioned. 4-Mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 1,1,3,3-tetrakis (mercaptomethylthio) propane, 5, are very particularly preferred , 7-dimercaptomethyl-1, 1 1 -dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1, 1 1 -dimercapto-3,6,9-trithiaundecane, 4,8-dimercapto-methyl-1 , 1 1 -dimercapto-3,6,9-trithiaundecane, trimethylolpropane tris (2-mercaptoacetate), trimethylolpropane tris (3-mercaptopropionate), pentaerythritol tetrakis (2-mercaptoacetate) and pentaerythritol tetrakis (3-mercaptopropionate ).

Finally, suitable components B) are also mercapto alcohols, such as. B. 2-mercaptoethanol, 3-mercaptopropanol, 1,3-dimercapto-2-propanol, 2,3-dimercaptopropanol or dithioerythritol.

According to a further preferred embodiment of the method according to the invention, the at least one component A) having at least one uretdione group and the at least one component B) having at least one hydroxyl and / or at least one thiol group are used in such amounts that the Component A) 0.5 to 2.0, preferably 0.7 to 1.5, especially preferably 0.8 to 1.2, very particularly preferably exactly one hydroxyl and / or thiol group of component B) is omitted.

To accelerate the reaction between the uretdione groups of component A) and the hydroxyl and / or thiol groups of component B), at least one salt-like catalyst C) with an imidazolium and / or imidazolinium cation is used in the process according to the invention.

Compounds suitable as catalysts C) are known as ionic liquids of the imidazolium and imidazolinium types and are used, for example, as solvents in chemical synthesis. Processes for their production are described, for example, in Chem. Rev. 99, 8, 2071-2084 and WO 2005/070896.

The catalysts C) are salt-like compounds containing a structural element of the general formulas (I) or (II)

in which

R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ independently represent identical or different radicals which are saturated or unsaturated, linear or branched, aliphatic, cycloaliphatic, araliphatic or aromatic organic radicals having 1 to 18 carbon atoms which are substituted or unsubstituted and / or have heteroatoms in the chain, the radicals also in combination with one another, optionally together with a further heteroatom, can form rings with 3 to 8 carbon atoms, which can optionally be further substituted,

R ³ , R ⁴ , R ⁵ and R ^{6 can} independently also represent hydrogen, and

R ^{7 represents} hydrogen or a carboxylate anion (COO). Preferred catalysts C) are salt-like compounds containing a structural element of the general formulas (I) or (II), in which

R ¹ and R ² independently represent the same or different radicals which are saturated or unsaturated, linear or branched, aliphatic, cycloaliphatic, araliphatic or aromatic organic radicals with 1 to 12 carbon atoms, which are substituted or unsubstituted and / or heteroatoms in the Have chain,

R ³ , R ⁴ , R ⁵ and R ^{6 represent} hydrogen, and where

R ^{7 represents} hydrogen or a carboxylate anion (COO).

Particularly preferred catalysts C) are salt-like compounds containing a structural element of the general formulas (I) or (II), in which

R ¹ and R ² independently of one another represent identical or different radicals which are saturated or unsaturated, linear or branched, aliphatic organic radicals having 1 to 12 carbon atoms,

R ³ , R ⁴ , R ⁵ and R ^{6 represent} hydrogen, and

R ^{7 represents} hydrogen or a carboxylate anion (COO).

Examples of suitable catalysts of the general formula (I) are those which contain a 1,3-dimethylimidazolium, 1-methyl-3-ethylimidazolium, 1-methyl-3-propylimidazolium, 1-methyl-3-butylimidazolium, 1 -methyl-3-pentylimidazolium-, 1-methyl-3-hexylimidazolium-, 1-methyl-3-octylimidazolium-, 1-methyl-3-nonylimidazolium-, 1 -methyl-3-decylimidazolium-, 1-decyl-3 -methylimidazolium-, 1 -Methyl-3-benzylimidazolium-, 1 -Methyl-3- (3-phenylpropyl) imidazolium-, 1 -Ethyl-3-methylimidazolium (EMIM) -, 1-isopropyl-3-methylimidazolium-, 1 - Butyl-3-methylimidazolium (BMIM), 1-hexyl-3-methylimidazolium, 1-heptyl-3-methylimidazolium, 1 - (2-ethyl) hexyl-3-methylimidazolium (OMIM), 1, 3-bis Contain (tert-butyl) imidazolium, 1,3-bis (2,4,6-trimethylphenyl) imidazolium or 1,3-dimethylbenzimidazolium cation.

Examples of suitable catalysts of the general formula (II) are those which have a 1,3-dimethylimidazolinium, 1-ethyl-3-methylimidazolinium, 1-butyl-3- methylimidazolium- 1,3-bis- (2,6-diisopropylphenyl) imidazolinium- or 1,3-bis (2,4,6-trimethylphenyl) imidazolinium-1 - (1-adamantyl) -3- (2,4,6 -trimethylphenyl) imidazolinium-,

1, 3-diphenyl-4,4,5,5-tetramethylimidazolinium, 1,3-di-o-tolyl-4, 4,5,5-tetramethylimidazolinium cation contain.

As a counterion to the imidazolium and imidazolinium cations, the catalysts C) present in the compositions according to the invention contain any inorganic and / or organic anions, such as. B. halide, sulfate, hydroxysulfate, sulfite, nitrate, carbonate, hydrogen carbonate, aryl sulfonate, alkyl sulfonate, trifluoromethyl sulfonate, alkyl sulfate, phosphate, dialkyl phosphate, hexafluorophosphate, hexafluorophosphate, trifluoromethyl borate, Bis (trifluoromethylsulfonyl) imide, dicyanamide and / or carboxylate anions.

The counterion to the imidazolium and imidazolinium cations can also be a carboxylate group (COO) which is bonded directly to the imidazolium cation as R ^{7 of} the general formula (I), the catalyst C) in this case in the form of a zwitterionic Has structure.

Suitable catalysts C) for the compositions according to the invention are, for example, 1,3-dimethylimidazolium chloride, 1,3-dimethylimidazolium-2-carboxylate,

1,3-Dimethylimidazolium dimethylphosphate, 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium bromide, 1-ethyl-3-methylimidazolium iodide, 1-ethyl-3-methylimidazolium nitrate, 1-ethyl-3-methylimidazolium, 1-ethyl-3-methylimidazolium 3-methylimidazolium methanesulphonate, 1-ethyl-3-methylimidazolium trifluoromethanesulphonate, 1-ethyl-3-methylimidazolium trifluoro (trifluoromethyl) borate, 1-ethyl-3-methylimidazolium hydrogen sulphate, 1-methyl-1-methyl-ethanesulphate 1-methyl-1-methyl-eimidazolium-1-methyl-1-methyl-eimidazolium Ethyl 3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium diethyl phosphate, 1-ethyl 3-methylimidazolium hexafluorophosphate, 1 - ethyl 3-methylimidazolium bis (trifluoromethanesulfonyl) imidazolium, 1-2-methyl-1-methyl-1-methyl Ethyl 3-methylimidazolium acetate, 1 -Ethyl-3-methylimidazolium- (L) - (+) - lactate, 1-methyl-3-propylimidazolium iodide, 1,3-diisopropyl-4,5-dimethylimidazolium-2-carboxylate, 1 - Butyl-3-methylimidazolium chloride, 1-butyl-3-methylimi dazolium bromide, 1 - butyl-3-methylimidazolium iodide, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium ethyl sulfate, 1-butyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, 1-butyl-3-methyl-butyl sulfate, 1-butyl-3-methylimidyl sulfate, 1-butyl-3-methylimidyl sulfate 3-methylimidazolium trifluoro (trifluoromethyl) borate, 1 -butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium dibutyl phosphate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium, 1-butyl-3-methylimidazolium methylimidazolium acetate, 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, bis (tert-butyl) -imidazolium-2-carboxylate, 1-hexyl-3-methylimidazolium chloride, 1-hexyl-3-methylimidazolium bromide-3 1 -hexyl - methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, 1-hexyl-3-methylimidazolium hexafluorophosphate, 1-methyl-3-n-octylimidazolium bromide, 1-methyl-3-n-octylimidazolium chloride, 1-methyl-3-n-octylimidazolium chloride octylimidazolium hexafluorophosphate, 1-decyl-3-methylimidazolium bis (trifluoromethanesulphonyl) imide, 1,3-dimethylimidazolinium chloride, 1,3-dimethylimidazolinium-2-carboxylate, 1,3-dimethylimidazolinium acetate, 1-ethyl-3-methylchloride 3-methylimidazolinium-2-carboxylate, 1-ethyl-3-methylimidazolinium acetate, 1-butyl-3-methylimidazolinium-2-carboxylate, 1,3-bis (2,6-diisopropylphenyl) imidazolinium chloride or 1,3-bis (2 , 4,6-trimethylphenyl) imidazolinium-1 - (1-adamantyl) -3- (2,4,6-trimethylphenyl) imidazolinium chloride and / or 1,3-diphenyl-4,4,5,5-tetramethylimidazolinium chloride.

Particularly preferred catalysts C) are imidazolium salts of the type mentioned with carboxylate anions, very particularly preferably 1,3-dimethylimidazolium-2-carboxylate, 1-ethyl-3-methylimidazolium-2-carboxylate, 1-ethyl-3-methylimidazolium acetate, 1 - Butyl 3-methylimidazolium-2-carboxylate and / or 1-butyl-3-methylimidazolium acetate.

In a further preferred embodiment, the catalysts C) come in the process according to the invention either individually or as mixtures of at least two such catalysts in an amount of 0.001 to 15% by weight, preferably 0.005 to 12% by weight, particularly preferably 0.01 to 10% by weight, based on the total weight of components A) and B), excluding any solvents, auxiliaries or additives present in these components.

If necessary, further co-catalytically active compounds can also be used in the process according to the invention for controlling the selectivity of the uretdione reaction. These are in particular organic zinc salts, such as. B. zinc (II) stearate, zinc (II) n-octanoate, zinc (II) -2-ethyl-1-hexanoate, zinc (II) naphthenate or zinc (II) acetylacetonate, which are used individually or as mixtures of at least two such co-catalysts, if at all in an amount of 0.01 to 100 mol%, based on the amount of catalyst C). The preferred co-catalyst is zinc (II) acetylacetonate.

The method according to the invention is outstandingly suitable for the production of polyurethane plastics and is used for this. The process according to the invention is preferably used for the production of coating compositions.

Therefore, compositions, preferably coating agents, contain either at least one component A) having at least one uretdione group, at least one component B) having at least one thiol group and at least one catalyst C) with an imidazolium or imidazolinium structure as well optionally further auxiliaries and additives or containing at least one, at least one polyaddition compound A2) which, in solvent-free form, has a free isocyanate group content of less than 5% by weight, at least one component B containing at least one hydroxyl and / or thiol group ) and at least one catalyst C) with an imidazolium or imidazolinium structure and, if appropriate, further auxiliaries and additives, likewise a subject of the invention. The at least one polyaddition compound A2) in solvent-free form preferably has a content of free isocyanate groups of less than 2% by weight and particularly preferably less than 1% by weight. Polyaddition compounds A2) free of isocyanate groups are very particularly preferred.

The process according to the invention is carried out and the compositions according to the invention are cured, depending on the activity of the catalyst used, generally in the temperature range from 20 to 200 ° C., preferably from 60 to 180 ° C., particularly preferably from 70 to 170 ° C. and very particularly preferably from 80 to 160 ° C., preferably over a period of 1 minute up to 12 hours, preferably 10 minutes to 3 hours.

Under these conditions, the uretdione groups originally contained in component A) generally react completely to form allophanate groups and / or thioallophanate groups and, if appropriate, isocyanurate groups.

Another object of the invention is the use of at least one composition according to the invention for the production of polyurethane plastics. In addition, the invention also provides the use of at least one composition according to the invention for the production of coating agents.

Any substrates can be used as substrates for the coatings formulated with the aid of the compositions according to the invention, such as, for. B. metal, wood, glass, stone, ceramic materials, concrete, hard and flexible plastics, textiles, leather and paper, which can optionally be hen verses with conventional primers before coating.

Further objects of the invention are coating agents comprising at least one composition according to the invention and a substrate coated with a coating agent according to the invention which is optionally cured under the action of heat.

The coating compositions formulated with the compositions according to the invention, which optionally contain the usual auxiliaries and additives known to the person skilled in the art from paint technology, such as. B. Solvents, UV stabilizers, antioxidants, leveling agents, rheology additives, slip additives, dyes, matting agents, Flame retardants, hydrolysis inhibitors, microbicides, algicides, water scavengers, thixotropic carriers, wetting agents, deaerating agents, adhesion promoters, fillers and / or pigments, which can be incorporated, give films with good lacquer properties under the curing conditions mentioned.

The invention also relates to polyurethane plastics, preferably coatings, which have been obtained by using the coating agents described above.

Examples

Unless otherwise stated, all percentages relate to weight.

The NCO contents were determined titrimetrically in accordance with DIN EN ISO 1 1909: 2007-05.

All viscosity measurements were carried out with a Physica MCR 51 rheometer from Anton Paar Germany GmbH (DE) according to DIN EN ISO 3219: 1994-10 at a shear rate 5 of 250 s-1.

The residual monomer contents were measured according to DIN EN ISO 10283: 2007-1 1 by gas chromatography using an internal standard.

The compositions of the uretdione model compounds were determined by gel permeation chromatography based on DIN 55672-1: 2016-03 (gel permeation chromatography (GPC) - Part 1: tetrahydrofuran (THF) as eluent), with the change that with a flow rate of 0, 6 ml / min instead of 1.0 ml / min was worked. The proportions of the different oligomers taken from the chromatograms in area%, which were determined with the aid of software, were approximately equated in each case with proportions in% by weight.

The König pendulum damping was determined in accordance with DIN EN ISO 1522: 2007-04 on glass plates.

The uretdione byproducts formed during the curing of the compositions according to the invention were determined using protocone-decoupled ¹³ C-NMR spectra (recorded using CDCl3 as solvent on a Bruker DPX-400 device). The individual structural elements show the following chemical shifts (in ppm): uretdione: 157.1; Isocyanurate: 148.4; Allophanate: 155.7 and 153.8.

The solvent resistance was determined using xylene as a typical paint solvent. For this purpose, a small amount of the solvent was placed in a test tube and a cotton swab was attached to the opening so that an atmosphere saturated with xylene was created inside the test tube. The test tube was then placed on the lacquer surface with a cotton ball and remained there for 5 minutes. After wiping off the solvent, the film was checked for destruction / softening / loss of adhesion. (0 = no change, 5 = film destroyed) Output connections

Manufacture of an HDI uretdione model connection (HDI-UD1)

Preparation of 1,3-bis (6-isocyanatohexyl) -1, 3-diazetidine-2,4-dione

According to the method described in Example 1 of EP-A 0 789 017, by tributylphosphine-catalyzed oligomerization of 1,6-diisocyanatohexane (HDI) and subsequent work-up by distillation 1,3-bis (6-isocyanatohexyl) -1, 3-diazetidine- 2,4-dione (ideal bis (6-isocyanatohexyl) uretdione) produced.

NCO content: 25.0%

monomeric HDI: <0.03%

Viscosity (23 ° C): 28 mPas

According to gel permeation chromatographic analysis (GPC), the following composition is present:

HDI uretdione (n = 2): 99.2% (according to GPC)

HDI isocyanurate (n = 3): 0.4% (according to GPC)

higher oligomers: 0.4% (according to GPC)

Production of bis (6-isocyanatohexyl) uretdione dimethyl urethane (HDI-UD1)

10 g (0.0595 eq) of the above-described HDI uretdione were dissolved in 30 ml of dichloromethane, 2 g (0.0625 mol) of methanol were added and the mixture was stirred at 40 ° C. under dry nitrogen until no IR spectroscopy showed after 8 h Isocyanate was more detectable. Dichloromethane and excess methanol were then removed using a rotary evaporator. The dimethyl urethane of bis (6-isocyanatohexyl) uretdione (HDI-UD1) was present as a colorless solid.

Uretdione group content: 21.0% (calculated as C2N2O2, molecular weight 84)

Manufacture of an HDI polvuretdione crosslinker (HDI-UD2)

1000 g (5.95 eq) of the above-described ideal bis (6-isocyanatohexyl) uretdione (NCO content: 25.0%) were dissolved in 800 g of butyl acetate, with 4.6 g (0.2% by weight ) a 10% solution of dibutyltin dilaurate (DBTL) in butyl acetate and heated to 80 ° C under dry nitrogen and stirring. A mixture of 347.5 g (4.76 eq) 2,2,4-trimethylpentane-1,3-diol and 154.7 g (1.19 eq) 2-ethyl-1 was added to this solution over the course of 2 hours -hexanol added dropwise. After a stirring time of 16 hours at 80 ° C., the NCO content was <0.2%. A practically colorless solution of an HDI polyurethane crosslinker (HDI-UD2) was obtained. NCO content: 0.16%

Uretdione group content: 10.8% (calculated as C2N2O2, molecular weight 84) Uretdione functionality: 5 (calculated)

Solid content: approx. 65%

Viscosity (23 ° C): 1400 mPas

Creation of a PDI uretdione model connection (PDI-UD1)

Preparation of 1,3-bis (5-isocyanatopentyl) -1, 3-diazetidine-2,4-dione

According to the process described in Example 1 of EP-A 0 789 017, tributylphosphine-catalyzed oligomerization of 1,5-diisocyanatopentane (PDI) instead of 1,6-diisocyanatohexane (HDI) and subsequent work-up by distillation 1,3-bis (5 - Isocyanatopentyl) -1, 3-diazetidin-2,4-dione (ideal bis (5-isocyanatopentyl) uretdione) produced.

NCO content: 27.3%

monomeric PDI: 0.03%

Viscosity (23 ° C): 22 mPas

According to gel permeation chromatographic analysis (GPC), the following composition is present:

HDI uretdione (n = 2): 98.7% (according to GPC)

HDI isocyanurate (n = 3): 0.7% (according to GPC)

higher oligomers: 0.6% (according to GPC)

Production of the dimethyl urethane of bis (5-isocyanatopentyl) uretdione (PDI-UD1)

10 g (0.065 eq) of the PDI uretdione described above were dissolved in 30 ml of dichloromethane, 2 g (0.068 mol) of methanol were added and the mixture was stirred at 40 ° C. under dry nitrogen until isocyanate was no longer detectable by IR spectroscopy after 8 h . Dichloromethane and excess methanol were then removed using a rotary evaporator. The dimethyl urethane of bis (5-isocyanatopentyl) uretdione (PDI-UD1) was present as a colorless solid. IR spectroscopy showed that there were no more free isocyanate groups (no isocyanate absorption band at 2270 cm ^-1 )

Uretdione group content: 22.3% (calculated as C2N2O2, molecular weight 84) Catalysts

1-Ethyl-3-methylimidazolium acetate (97%), Sigma-Aldrich Chemie GmbH, Munich, DE

1,3-Dimethylimidazolium-2-carboxylate, prepared according to the method described in J. Org. Chem. 73, 14, 5582-5584

1-ethyl-3-methylimidazolium-2-carboxylate, prepared according to the process described in Chem. Eur. J. 2016, 22, 16292-16303

Example 1 :

6.8 mg (0.04 mmol) of 1-ethyl-3-methylimidazolium acetate together with 28.2 mg (0.21 mmol) of 2- (2-ethoxyethoxy) ethanol (carbitol) in 1, were placed in an oven-dried and pressure-resistant reaction vial. 0 ml of absolute tetrahydrofuran (THF) dissolved. Then 80.0 mg (0.20 mmol) of the HDI-uretdione model compound (HDI-UD1) were added and the contents of the closed reaction vessel were stirred at 80 ° C. for one hour. After the solvent had been removed in a high vacuum, the ¹³ C-NMR spectrum of the mixture showed complete conversion of the uretdione groups used to allophanate and isocyanurate groups. The molar ratio of allophanate to isocyanate groups was 90:10.

Example 2:

In an oven-dried and pressure-resistant reaction vial, 8.1 mg (0.04 mmol) of 1,3-dimethylimidazolium-2-carboxylate were dissolved together with 28.2 mg (0.21 mmol) of carbitol in 1.0 ml of absolute THF. Then 80.0 mg (0.20 mmol) of the HDI uretdione model compound (HDI-UD1) were added and the contents of the closed reaction vessel were stirred at 80 ° C. for one hour. After removing the solvent in a high vacuum, the ¹³ C-NMR spectrum of the mixture showed complete conversion of the uretdione groups used to allophanate and isocyanurate groups. The molar ratio of allophanate to isocyanurate groups was 87: 13.

Example 3:

In an oven-dried and pressure-resistant reaction vial, 6.2 mg (0.04 mmol) of 1-ethyl 3-methylimidazolium-2-carboxylate were dissolved together with 28.2 mg (0.21 mmol) of carbitol in 1.0 ml of absolute THF. 80.0 mg (0.20 mmol) of the HDI-uretdione model compound (HDI-UD1) were then added and the contents of the closed reaction vessel were stirred at 80 ° C. for one hour. After removing the In a solvent in a high vacuum, the ¹³ C-NMR spectrum of the mixture showed complete conversion of the uretdione groups used to allophanate and isocyanurate groups. The molar ratio of allophanate to isocyanurate groups was 88:12.

Example 4:

In an oven-dried and pressure-resistant reaction vial, 0.05 g (0.3 mmol) of sodium ethyldithiocarbonate were dissolved together with 0.23 g (1.7 mmol) of carbitol in 12.1 ml of absolute tetrahydrofuran (THF). Then 0.61 g (1.6 mmol) of the PDI uretdione model compound (PDI-UD1) were added and the contents of the sealed reaction vessel were stirred at 24 ° C. for one hour. After removing the solvent in a high vacuum, the ¹³ C-NMR spectrum of the mixture showed complete conversion of the uretdione groups used to allophanate and isocyanurate groups. The molar ratio of allophanate to isocyanurate groups was 90:10.

Example 5 (according to the invention and comparison):

100 g (0.559 eq) of a commercially available, aromatic-free, branched polyester polyol with a solids content of 75% in butyl acetate and an OH content of 9.5%, based on the solid resin, available under the name Desmophen 775 XP (Covestro Deutschland AG, Leverkusen, DE), were mixed with 197.6 g (0.254 eq) of the HDI polyurethane crosslinker (HDI-UD2) corresponding to an equivalent ratio of hydroxyl groups to uretdione groups of 1.1: 1 to form a coating agent and, after adding 3.0 g (18, 2 mmol, 1.0%) 1-ethyl-3-methylimidazolium acetate as a catalyst was applied to a degreased glass plate using a dumbbell in an application layer thickness of 150 μm.

For comparison, 100 g of Desmophen 775 XP and 197.6 g of HDI polyurethane crosslinker (HDI-UD2), likewise corresponding to an equivalent ratio of hydroxyl groups to uretdione groups of 1.1: 1, were used in the same process

Coating agent prepared and after the addition of 2.9 g (18.8 mmol, 1.0%) 1,8-diazabicyclo [5.4.0] undec-7-en (DBU) as a catalyst using a paint dumbbell in an application layer thickness of 150 gm applied to a degreased glass plate.

After flashing off at room temperature for 15 minutes, both paints were cured within 30 minutes at 100.degree. In both cases, hard, elastic and completely transparent coatings were obtained, which differed as follows:

Example 6:

51.4 g (0.421 eq) pentaerythritol tetrakis (3-mercaptopropionate) (solids content: 100%, SH content: 26%), available under the name THIOCURE PETMP (Bruno Bock Chemische Fabrik GmbH & Co. KG, Marschacht, DE ), were mixed with 148.6 g (0.191 eq) of the HDI polyurethane crosslinker (HDI-UD2) corresponding to an equivalent ratio of thiol groups to uretdione groups of 1.1: 1 to form a coating agent and after adding 2.0 g (12.1 mmol, 1.0%) 1-ethyl-3-methylimidazolium acetate as a catalyst was applied to a degreased glass plate using a paint dumbbell in an application layer thickness of 150 μm. After flashing off at room temperature for 15 minutes, the paint was cured within 30 minutes at 100.degree.

A smooth, colorless-transparent coating was obtained which had a pendulum damping of 160 s and a xylene resistance of 1-2.

Claims

Claims

1 . Process for the preparation of compounds containing allophanate and / or thioallophanate groups comprising reaction of

A) at least one, at least one uretdione group

Component with

B) at least one component having at least one hydroxyl and / or thiol group in the presence

C) at least one catalyst containing a structural element of the general formulas (I) and / or (II)

in which

R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ independently represent identical or different radicals which are saturated or unsaturated, linear or branched, aliphatic, cycloaliphatic, araliphatic or aromatic organic radicals having 1 to 18 carbon atoms , which are substituted or unsubstituted and / or have heteroatoms in the chain, the radicals also in combination with one another, optionally together with another heteroatom, can form rings with 3 to 8 carbon atoms, which can optionally be further substituted, where

R ³ , R ⁴ , R ⁵ and R ^{6 can} independently also represent hydrogen, and

R ^{7 stands} for hydrogen or a carboxylate anion

(COO) stands,

wherein the at least one component A) having at least one uretdione group is isocyanate-functional by reaction Compounds A1) containing uretdione groups are polyaddition compounds A2) obtainable with alcohols and / or amines which, in solvent-free form, have a free isocyanate group content of less than 5% by weight.

2. The method according to claim 1, characterized in that component A1) is uretdione-containing compounds based on PDI, HDI, IPDI, XDI, NBDI and / or H12-MDI, which preferably have an average NCO functionality of have at least 1.6 and particularly preferably have a content of uretdione structures (calculated as C2N2O2, molecular weight = 84) of 10 to 25% by weight.

3. The method according to claim 1 or 2, characterized in that the polyaddition compounds A2) are compounds obtained by reacting isocyanate-functional compounds A1) containing uretdione groups with at least difunctional polyols of the molecular weight range 62 to 22,000 and optionally monoalcohols while maintaining an equivalent ratio from isocyanate groups to isocyanate-reactive groups of 2: 1 to 0.5: 1.

4. The method according to any one of claims 2 to 4, characterized in that the uretdione group-containing polyaddition compounds A2) in solvent-free form have a content of free isocyanate groups of less than 2 wt .-%, preferably less than 1 wt .-% and especially are preferably free of isocyanate groups.

5. The method according to any one of claims 1 to 4, characterized in that component B) is at least difunctional polyols in the molecular weight range 62 to 22,000.

6. The method according to any one of claims 1 to 5, characterized in that components A) and B) are used in such amounts that for each uretdione group of component A) 0.5 to 2.0 hydroxyl and / or thiol groups component B) is omitted.

7. The method according to any one of claims 1 to 6, characterized in that component C) is a catalyst containing a structural element of the general formulas (I) and / or (II), in which

R ¹ and R ² independently represent the same or different radicals which are saturated or unsaturated, linear or branched, aliphatic, cycloaliphatic, araliphatic or aromatic organic radicals with 1 to 12 carbon atoms, which are substituted or unsubstituted and / or heteroatoms in the Have chain,

R ³ , R ⁴ , R ⁵ and R ^{6 represent} hydrogen, and where

R ^{7 represents} hydrogen or a carboxylate anion (COO).

8. The method according to any one of claims 1 to 7, characterized in that the component C) is a catalyst containing a structural element of the general formulas (I) and / or (II), in which

R ¹ and R ² independently of one another represent identical or different radicals which are saturated or unsaturated, linear or branched, aliphatic organic radicals having 1 to 12 carbon atoms,

R ³ , R ⁴ , R ⁵ and R ^{6 represent} hydrogen, and

R ^{7 represents} hydrogen or a carboxylate anion (COO).

9. The method according to any one of claims 1 to 8, characterized in that the catalyst C) is imidazolium salts of the type mentioned with carboxylate anions, very particularly preferably 1, 3-dimethylimidazolium-2-carboxylate, 1-ethyl 3- methylimidazolium-2-carboxylate, 1-ethyl-3-methylimidazolium acetate, 1-butyl-3-methylimidazolium-2-carboxylate and / or 1-butyl-3-methylimidazolium acetate.

10. The method according to any one of claims 1 to 9, characterized in that component C) in an amount of 0.001 to 15 wt .-%, based on the total weight of components A) and B), excluding any components present in these components Solvents, auxiliaries or additives are present.

1 1. Composition containing either at least one component A) having at least one uretdione group, at least one component B) having at least one thiol group and at least one catalyst C) with an imidazolium or imidazolinium structure and optionally further auxiliaries and additives or containing at least one, at least a

Polyaddition compound A2), which in solvent-free form has a content of free isocyanate groups of less than 5% by weight, at least one component B) having at least one hydroxyl and / or thiol group and at least one catalyst C) with imidazolium or imidazolinium Structure and, if necessary, other auxiliaries and additives.

12. Use of compositions according to claim 1 1 for the production of polyurethane plastics, in particular for the production of coating agents.

13. Coating agents containing compositions according to claim 1 1.

14. Substrate coated with an optionally heated

cured coating agent according to claim 13.

15. Polyurethane plastic, obtained from a composition according to claim 11 which has optionally cured under the action of heat.