ISOCYANATE MIXTURES BLOCKED BY DIMETHYLPYRAZOLE Russian patent published in 2007 - IPC C08G18/70 C08G18/77 C08G18/80 

FIELD: chemistry of polymers, chemical technology.

SUBSTANCE: invention relates to mixtures consisting of blocked polyisocyanates designated as hardening agents in monocomponent lacquers of hot drying and comprising: (a) blocked polyisocyanate based on 1,6-diisocyanate hexane; (b) blocked polyisocyanate based on cycloaliphatic diisocyanates chosen from group comprising 1-isocyanato-3,3,5-trimethyl-5-ixocyanatomethylcyclohexane, bis-(4-isocyanatocyclohexyl)methane, 2,6-bis-isocyanatonorbornane, 2,5-bis-isocyanatonorbornane, 1,4-bis-isocyanatomethylcyclohexane and their mixtures, and (c) 3,5-dimethylpyrazole as a single blocking agent of agent of polyisocyanates named in (a) and (b). Blocked polyisocyanates are taken in the weight ratio (a) : (b) = 1:(1.8-2.2). Using mixtures of blocked polyisocyanates provides preparing clear lacquers with good acid resistance, stability against scratching and thermal yellowing.

EFFECT: improved and valuable properties of agents.

1 cl, 6 ex