Patent ID: 8685536
Filing Date: 2014-04-01
Classification: B05D,H01B,Y10T

Abstract:
1. A polyamide-imide resin insulating coating material, comprising: a polyamide-imide resin obtained by reacting, in a mixed solvent, an isocyanate component comprising (i) 4,4′-diphenylmethane diisocyanate and (ii) an isomer of 4,4′-diphenylmethane diisocyanate other than 4,4′-diphenylmethane diisocyanate, with an acid component comprising a trimellitic anhydride, wherein: a total compounding ratio, obtained by averaging a compounding ratio of the 4,4′-diphenylmethane diisocyanate in the isocyanate component and a compounding ratio of the trimellitic anhydride in the acid component, is in the range of 85 to 98 mol %; the mixed solvent comprises γ-butyrolactone as a main solvent and at least one nitrogen-containing high boiling point polar solvent selected from the group consisting of N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), and N,N-dimethylacetamide (DMAC); and an organo-silica sol comprising γ-butyrolactone as a main dispersion solvent of the organo-silica sol; wherein the organo-silica sol is dispersed in the polyamide-imide resin insulating coating material; and γ-butyrolactone accounts for 70% by weight or more of the amount of all solvents of the polyamide-imide resin insulating coating material.