The present invention relates to coating compositions which are suitable for the production of heat resistant films and coatings and contain a) 100 parts by weight of organic compounds having (i) carbodiimide and/or uretoneimine groups and (ii) blocked isocyanate groups, b) 2 to 100 parts by weight of intramolecular carboxylic acid anhydrides which have a molecular weight of 98 to 500 and may contain free carboxyl groups and c) 2 to 100 parts by weight of polyhydric alcohols which have a molecular weight of 62 to 400 and a hydroxyl functionality of 2 to 4. The present invention also relates to heat-resistant substrates, in particular for wires, coated with these coating compositions.

The present invention relates to polyisocyanates containing i) 0.5 to 10 wt. % of amide and/or imide structural units (calculated as --CO--N.dbd., MW=42), ii) 5 to 20 wt. % of isocyanate groups (calculated as --NCO, MW=42) blocked with blocking agents which are monofunctional in the context of the isocyanate addition reaction and iii) 0 to 30 wt. % of chemically incorporated urethane groups (calculated as --NH--CO--O--, MW=59) obtained from the reaction of isocyanate groups with the hydroxyl groups of organic polyhydroxyl compounds. The present invention also relates to a process for the production of these lacquer polyisocyanates, their use as a binder for stoving lacquers optionally in combination with organic polyhydroxyl compounds and to their use as a binder component containing free hydroxyl groups and optionally blocked isocyanate groups by reacting and/or blending the polyisocyanates with organic polyhydroxyl compounds having a molecular weight of 62 to 350.

The present invention relates to novel binders for electrical insulating enamels, comprising at least one hydroxy- and/or amino-functional polyurethane containing urea and/or hydantoin groups, prepared by reacting: a) from 15 to 40 wt. % of an organic polyisocyanate or of a mixture of organic polyisocyanates, b) from 5 to 20 wt. % of at least one aspartic acid ester, and c) from 5 to 50 wt. % of a polyhydroxy compound having a molar weight from 62 to 3000 g/mol, in d) from 25 to 50 wt. % of a solvent or of a solvent mixture and at least one blocked isocyanate component containing ester, imide, amide, and/or urethane groups, at least one organic solvent, and optionally further auxiliary substances and additives whereby the resulting enamels being distinguished by high temperature stability and good solderability.