High frequency resistant coating used for electronic machines comprises heat cured polyurethane prepared from block diisocyanate and esterified polyol in specified ratio

摘要

High frequency resistant coating comprises a heat cured polyurethane prepared from a block diisocyanate, comprising a diisocyanate, a methylol alkane and a tert. amine in a mol. ratio of diisocyanate to methylol alkane of 0.7-1.3:0.1-0.6, and an esterified polyol, comprising terephthalate, an anhydride, p,p-diaminophenyl methane and a polyol(s) in a mol. ratio of 0.7-1.3:0.7-1.3:0.3-0.7:2-4. An Independent claim is included for an enameled wire comprising a metal core and a coating as above.