Photographic etching resist and preparation thereof

Abstract

Abstract A printing plate of the type which is prepared by coating a metal supporting surface with a photo-insolubilizable polymer, exposing the coating to a light image, developing the exposed coating by treatment with a liquid dissolving the unexposed areas only of the coating so that the exposed areas remain as a resist layer on the metal surface, and etching the metal surface with the resist layer thereon by means of an aqueous etching liquid therefore, is given increased resistance in the exposed regions to the attack of the etching liquid by incorporating into the developing liquid a hydrophobizing agent which is either an organic compound containing at least one fluorine substituted alkyl group of an organic silane or siloxane compound containing at least one alkyl or aryl group linked to at least one of its silicon atoms, the hydrophobizing agent also containing a reactive group capable of chemically reacting with the photoinsolubilizable polymer. The polymer preferably includes active hydrogen atoms after insolubilization and preferred chemically active groups in the hydrophobizing agent are acid anhydride, isocyanate, epoxy, and acid chloride groups.

Inventors

• 👤 Johan Lodewijk Verelst
• 👤 Jozef Frans Willems

Bibliographic Details