Patent ID: 6949281

Claim:
A varnish composition which comprises: a polymer ingredient containing polyamic acid B represented by formula (1): wherein R 1 is a tetravalent organic radical derived from tetracarboxylic acids, and R 2 is a divalent organic radical derived from diamines, and m is a natural number; a polyamic acid A represented by formula (2), having a side chain of not less than 3 carbon atoms: wherein R 1 ′ is a tetravalent organic radical derived from tetracarboxylic acids, R 2 ′ is a divalent organic radical derived from diamines, at least one of the tetravalent and divalent organic radicals has a side chain of not less than 3 carbon atoms, and m′ is a natural number; an N-substituted polyamide represented by formula (3): wherein R 3 is a divalent organic radical derived from dicarboxylic acids; R 4 is a divalent organic radical derived from diamines; R 5 and R 6 represent a monovalent organic radical or hydrogen in which the percentage of the substitution of the monovalent organic radical is not less than 30% and the organic radical may be plural species, and n is a natural number; and a solvent for dissolving the polymer ingredients so that the varnish composition contains 0.1 to 40% by weight of the polymer ingredient.