Polyvinyl acetals having imido groups and use thereof in photosensitive compositions

摘要

This invention relates to polyvinyl acetals containing the units A, B, C and D, wherein A is present in an amount of 0.5 to 20 wt.-% and is of the formula B is present in an amount of 15 to 35 wt.-% and is of the formula C is present in an amount of 10 to 50 wt.-% and is of the formula wherein R<1> is an alkyl group with up to 4 carbons, which is optionally substituted by an acid group, or a phenyl group, to which an acid group is attached, wherein the phenyl group optionally comprises 1 to 2 further substituents selected from halos, amino, methoxy, ethoxy, methyl and ethyl groups, or is a group X-NR<6>-CO-Y-COOH, wherein X is an aliphatic, aromatic or araliphatic spacer group, R<6> is hydrogen or an aliphatic, aromatic or araliphatic moiety and Y is a saturated or unsaturated chain- or ring-shaped spacer group, and this unit C may be contained several times with various moieties R<1> independent of one another, and D is present in an amount of 25 to 70 wt.-% and is of the formula wherein n is an integer from 1 to 3 and R<2> and R<3> are a hydrogen or a methyl group, and R<4> and R<5> independent of one another are alkyl groups having no more than 4 carbons or R<4> and R<5>, together with the two carbons they are attached to, represent a 5- or 6-membered carbocyclic ring. In addition, photosensitive compositions containing these polyvinyl acetals are described.