摘要 |
A curable powder coating composition comprises (a) a copolymer produced fromai) 5 to 10 wt % of a C1 to C4 alkyl diester of an ethylenically unsaturated dicarboxylic acid,aii) 10 to 45 wt % of a glycidylester of an ethylenically unsaturated carboxylic acid,aiii) 10 to 35 wt % of an alkenyl ester of a branched tertiary carboxylic acid wherein the acid moiety contains nine carbon atoms, andaiv) 0 to 45 wt % of a C1 to C12 alkyl ester of an ethylenically unsaturated carboxylic acid having from 3 to 4 carbon atoms in the acid moiety, the percentages of ai) to av) are relative to the total weight of the polymer adding up to 100%; and(b) a blend comprising (bi) C4 to C16 (cyclo)aliphatic dicarboxylic acid and (bii) a polyester resin having an acid value of from 4500 to 4900 mmole/kg produced from a C5 to C12 branched polyhydroxyalkane and a C4 to C16 (cyclo)aliphatic dicarboxylic acid or anhydride in a polyhydroxyalkane:dicarboxylic acid molar ratio of from 0.2:1 to 0.4:1,blend (b) having an acid value of from 5000 to 10,000 and the acid:epoxy molar ratio being from 0.70:1 to 1.10:1.
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