Diazo light-sensitive copying composition and process of using in the manufacture of screen printing stencils

US4021243A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Hartmut Steppan · Wiesbaden, DE
• Hans Ruckert

Key dates

• Filing date: Jan 22, 1976
• Grant date: May 3, 1977
• Expiry date: Jan 22, 1996

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/12
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

This invention relates to a light-sensitive copying composition for the preparation of screen printing stencils comprising a condensation product of an aromatic diazonium compound in admixture with a hydrophilic hardenable binder, the condensation product containing at least one unit each of the general types A(-D).sub.n and B which are connected by bivalent intermediate members derived from a condensable carbonyl compound, wherein PA1 A is a radical of a compound containing at least two isocyclic or heterocyclic aromatic nuclei, which compound is capable of condensation in at least one position with an active carbonyl compound in an acid medium, PA1 D is a diazonium salt group attached to an aromatic carbon atom of A, PA1 n is an integer from 1 to 10, and PA1 B is a radical of a compound free of diazonium groups, which compound is capable of condensation in at least one position with an active carbonyl compound in an acid medium, And wherein the anion of the diazonium salt is derived from an aliphatic monosulfonic acid having 1 to 6 carbon atoms.