Asymmetric linear polyimides and their polyimide precursors, and their manufacturing methods

Abstract

Disclosed is a linear polyimide precursor having an intrinsic viscosity of not less than 0.5 dL/g and composed of a repeating unit represented by at least one formula selected from the group consisting of the general formula (1) below and the general formula (2) below. In the general formulae (1) and (2), X represents a divalent aromatic group other than a residue of 1,4-bis(4-aminophenoxy)benzene and a residue of bis(4-amino-3-methylphenyl)methane or an aliphatic group. Since this linear polyimide precursor has high glass transition temperature and high toughness, while exhibiting excellent solubility and thermoplasticity, it is suitably used as a raw material for an asymmetric polyimide which is useful as an adhesive resin for flexible printed circuits (FPC) or the like.

Dependencies are inferred from the claim text.