Patent ID: 8293371

Claim:
A polyimide resin comprising a repeating unit represented by the following formula (1): or comprising the repeating unit of the formula (1) and at least one repeating unit represented by the following formula (2): wherein X is a divalent aliphatic group having 2 to 39 carbon atoms, a divalent alicyclic group having 3 to 39 carbon atoms, a divalent aromatic group having 6 to 39 carbon atoms or a combination of the preceding divalent groups; a main chain of X optionally has at least one intervening bonding group selected from the group consisting of —O—, —SO 2 —, —CH 2 —, —C(CH 3 ) 2 —, —OSi(CH 3 ) 2 —, —C 2 H 4 O— and —S—; and X optionally has at least one functional group selected from the group consisting of carboxyl group, hydroxyl group and carbonyl group in a concentration F of more than zero but not more than 1 meq/g polyimide resin, a content of the repeating unit of the formula (1) being 50 mol % or more of a total of the repeating units, and a logarithmic viscosity η of the polyimide resin being from 0.3 to 2 dL/g when measured at 30° C. using a 0.5 g/dL solution of the polyimide resin in N-methyl-2-pyrrolidone.