COMPOSITION COMPRISING BLOCKED POLYISOCYANATE

摘要

PROBLEM TO BE SOLVED: To stabilize a blocked polyisocyanate against thermal yellowing. SOLUTION: The method of stabilizing the blocked polyisocyanate against thermal yellowing uses at least one compound represented by one of formulas I-III. The composition comprises the blocked polyisocuanate and at least one compound according to formulas I-III. The coating material comprises this composition. The coating and the substrate contain this coating material. In formulas I-III, R1to R4stand independently of one another for hydrogen or for a 1-25C alkyl group or, in combination of two, three or four of the groups R1to R4, for a 1-25C aliphatic ring system, where in the case of formula I, R2and R3taken together or R3and R4taken together may also denote a substituted or unsubstituted benzene ring which is fused onto the pyrazole ring. COPYRIGHT: (C)2004,JPO