Process for coating electrically conductive objects with polyurethane

US4357221A · kind A · utility

Assignee

• BASF SE

Inventors

• August Lehner
• Juergen Gimpel · Ludwigshafen, DE
• Ingolf Buethe · Haßloch, DE
• Heinrich Hartmann · Schifferstadt, DE
• Hans-Uwe Schenck · Monsheim, DE

Key dates

• Filing date: Feb 5, 1981
• Grant date: Nov 2, 1982
• Expiry date: Feb 5, 2001

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/835
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for coating electrically conductive objects comprising PA0 A. immersing said object as the anode of an electric current in an aqueous polyurethane dispersion prepared by PA1 (1) forming a polyurethane solution by reacting an organic polyisocyanate in the presence of an organic solvent with PA2 (a) an acrylic ester diol having a molecular weight of between 146 and 3,000; PA2 (b) an organic polyhydroxyl compound other than (a) having a molecular weight between 400 and 5,000 selected from the group consisting of polyester, polyols, polyether polyols, polycarbonates, polylactones, and mixtures thereof; and PA2 (c) a chain extender selected from the group consisting of diols, triols, diamines, aminoalcohols, having a molecular weight between 62 and 400, water, and mixtures thereof; PA1 (2) forming an anionic polyurethane addition product by reacting said polyurethane solution with a mercaptocarboxylic acid salt in the presence of a solvent; PA1 (3) adding water; and PA1 (4) removing the organic solvent, and PA0 B. passing an electric current between the anode and a cathode which is also dispersed in said dispersion, and PA0 C. irradiating said object with ultraviolet radiation…