Polyimides, a process for their preparation and their use, and tetracarboxylic acids and tetracarboxylic acid derivatives

Claim 1

A soluble photocrosslinkable homo- or in a suitable organic solvent or copolyimide of at least one aromatic tetracarboxylic acid and at least one diamine, which essentially contains 0.1 to 100 mol % of at least one structural element of the formula I ##STR43## and 99.9 to 0 mol % of at least one structural element of the formulae II and/or III ##STR44## in which Z is at least one tetravalent radical of the formula IV, V, VI or VII ##STR45## in which the free bonds are in the ortho-position relative to one another and Y is a direct bond, --CH 2 --, --(CH 2 ) 2 --, --O--, --S--, --SO--, --SO 2 --, --CO--, --NR-- or --CRR 1 --, in which R is a hydrogen atom, C 1 -C 10 -alkyl, phenyl, naphthyl or phenyl-(C a H 2a )--, where a is 1-4, and R 1 is R, with the exception of a hydrogen atom, R 0 is C 1 -C 10 -alkyl, halogen, --CN, --NO 2 , C 1 -C 12 -alkoxy, phenoxy, naphthoxy or phenyl-(C a H 2a )--, where a is 1-4, n' is 0, 1 or 2, X is an unsubstituted or substituted divalent aliphatic radical, which can be interrupted by heteroatoms or aromatic, heterocyclic or cycloaliphatic groups, a substituted or unsubstituted heterocyclic, cycloaliphatic or araliphatic radical, an aromatic radical, in which two aryl nuclei are linked via an aliphatic group, or an aromatic radical which is substituted by at least one alkyl group, cycloalkyl group, alkoxy group, alkoxyalkyl group, alkylthio group, alkyl-thioalkyl group, hydroxyalkyl group, hydroxyalkoxy group, hydroxyalkylthio group, aralkyl group or, in the case of two adjacent C atoms of the aromatic radical, by an alkylene group, Q' is a trivalent aromatic radical, Z' has the same meaning as Z or is a tetravalent organic radical other than Z and X' is the divalent radical, other than X, of an organic diamine, and in which Z in formula I can also be a tetravalent benzophenone radical if structural elements of the formula III are present.