Hardener for photographic material with binder made of gelatin

摘要

The hardener for photographic material with gelatine as its main binder ingredient contains a carbamoyl pyridinium salt whose amine constant is derived from a sec amine, transformed by intramolecular cyclisation into a photographically inert material. Also claimed is a photographic material contg. the hardener. PREFERRED COMPOUND - (I) is present in the photographic material at a concn of 0.1-0.4 moles per g gelatine.