Patent ID: 7728102

Claim:
A polyamide-imide resin which is a copolymerized polyamide-imide that consists essentially of constitutional units represented by Formulae (1), (2), and (3) shown below: wherein R 1 and R 2 are the same or different, and independently represent hydrogen or C 1-4 alkyl or alkoxy; and Y represents a direct linkage or ether linkage; wherein R 3 and R 4 are the same or different, and independently represent hydrogen or C 1-4 alkyl or alkoxy; and wherein R 5 and R 6 are the same or different, and independently represent hydrogen or C 1-4 alkyl or alkoxy, and wherein the polyamide-imide resin satisfies the molar ratios of Formula (1)/Formula (2)=1/99 to 99/1 and [Formula (1)+Formula (2)]/Formula (3)=30/70 to 1/99.