Protein contng photo resist compsn with photoisomerisable cpd - which on exposure has greater enzyme inhibiting power

摘要

Photosensitive compsn. comprises a protein, which is hydrolysable by an active enzyme, and a photo-isomerisable cpd. which on exposure forms an isomer which has a greater inhibiting effect on proteolytic enzymes than the original isomer. Pref. phot-isomerisable cpds. are azobenzenes able to form cis-trans-isomers partic. of formula: (where R is H, 1-4C alkyl or alkoxy, COOH or R forms a naphtalene ring with the phenyl gp.). Specif. R is H, m or pmethyl, p-methoxy or forms a naphthalene ring. The protein is pref. photographic gelatine. The layer also pref. contains a tanning agent and the wet thickness of the layer is 10-400 mu. Used for prepg. photoresists, the prodt. is more stable to storage than earlier prodts.