Conductive organic coatings

US6479103B1 · kind B1 · utility

Assignee

• Henkel Kommanditgesellschaft auf Aktien · DE

Inventors

• Winfried Wichelhaus · Mettmann, DE
• Wolfgang Lorenz · Dormagen, DE
• Andreas Kunz · Remscheid, DE
• Wolfgang Krey · Wuppertal, DE

Key dates

• Filing date: Aug 7, 2000
• Grant date: Nov 12, 2002
• Expiry date: Aug 7, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09D163/00
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Conductive and weldable anti-corrosive compositions based on (blocked) polyurethane resins, epoxy resins, together with curing agents containing nitrogen and conductive extenders are suitable for coating metal surfaces, in particular sheet steel in the coil coating process. These compositions are distinguished by a low stoving temperature, a distinct reduction in white rust on galvanized sheet steel in the salt spray test and by an improvement in the adhesion of the organic coating on the metallic substrate. These coatings furthermore also achieve adequate corrosion protection with a thin chromium coating, preferably also in Cr-free pretreatment processes. Sheet metal coated in this manner may be spot welded using any conventional processes.