COATING COMPOSITION

摘要

The invention relates to a high gloss car wash-resistant coating composition comprising an epoxy-functional binder and a cross-linker reactive with the epoxy groups of the binder and a method to prepare such a car wash-resistant coating. The invention further relates to the use of said coating composition, as a pigment-free top coat or a clear coat, in the finishing and refinishing of articles, for example motorcycles, cars, trains, buses, trucks, and aeroplanes. The coating composition after curing forms a coating having an initial gloss of at least 81 GU and a loss of gloss (LoG) of less than 0.25, the loss of gloss being determined by the formula (I): LoG = (1 - e<SUP>(A/X)</SUP>) / (1 + e<SUP>K</SUP>) + (1 - e <SUP>D*?Tg</SUP>) wherein K = B * (Tg <SUB>onset</SUB>- C) In formula (I) A = -8.03, B = -0.21, C = 328 and D = -0.00304. X reflects the cross-link density parameter in kPa/K, Tg <SUB>onset</SUB> the onset temperature of the Tg transition in K and ?Tg the width of the glass transition temperature in K, all three parameters determined in a DMA test at 11 Hz and a heating rate of 5°C/min.