A material for dielectric films is a polymerizable composition containing an adamantanepolycarboxylic acid represented by following Formula (1):wherein X is a hydrogen atom, a carboxyl group or a hydrocarbon group; and Y.sup.1, Y.sup.2, Y.sup.3 and Y.sup.4 are the same as or different from one another and are each a single bond or a bivalent aromatic cyclic group; an aromatic polyamine represented by following Formula (2): wherein Ring Z is a monocyclic or polycyclic aromatic ring; and R.sup.1 and R.sup.2 are each a substituent bound to Ring Z, are the same as or different from each other and are each an amino group, a mono-substituted amino group, a hydroxyl group or a mercapto group; and a solvent other than ketones and aldehydes, in which the adamantanepolycarboxylic acid and aromatic polyamine are dissolved in the solvent ##STR00001## ##STR00002##