| 摘要 |
Powder coating compositions comprising (a) an epoxy resin, (b) at least one polycarboxylic acid of formula I or II (see fig I and II) wherein R1, R2, R3 and R4 are each independently of one another a hydrogen atom, C1-C4alkyl or the radical -CH2-CH2-COOH, R5 and R6 are each independently of the other a hydrogen atom, C1-C4alkyl, the radical -CH2-CH2-COOH or, when taken together, are an unsubstituted or alkyl-substituted methylene or polymethylene group, each of 1 to 7 atoms, wi th the proviso that at least two of the substituents R1 to R6 are the radical -CH2-CH2-COOH, the substituents R are each independently of one another a hydrogen atom or the radical the ratio of the carboxyl groups present in the 2-carboxycyclohexanecarbonyl radical to the RO groups being 0.5 to 1.0, m is an integer from 2 to 5, n is an intger from 0 to 10, and X is a direkt bond or an aliphatic or cycloaliphatic radical, and (c) a carboxyl-terminated saturated polyester, tolyl biguanide or dicyandiamide, are suitable for producing matt coatings on surfaces, especially on metal surfaces.
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