Heat hardenable coating composition based on polyurethane urea and coated substrate prepared therefrom

US4935485A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Josef Pedain · Cologne, DE
• Wilhelm Thoma · Leverkusen, DE
• Walter Schroer · Leverkusen, DE
• Waldemar Kling · Kandern, DE

Key dates

• Filing date: Jan 3, 1989
• Grant date: Jun 19, 1990
• Expiry date: Jan 3, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/4833
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention is directed to a heat hardenable coating composition containing PA1 (A) a prepolymer containing an average of 2-4 ketoxime-blocked isocyanate groups, having an average molecular weight of about 500 to 15,000 and based on an aromatic polyisocyanate and a polyhydroxyl component which contains about 20-100% by weight of ethylene oxide units and PA1 (B) a cross-linking agent corresponding to the following formula ##STR1## in which R and R.sup.1 denote H or C.sub.1 -C.sub.4 -alkyl, the equivalent ratio of blocked isocyanate groups in (A) to NH.sub.2 groups in (B) being about 1.35:1 to 0.95:1. The invention is also directed to the coated substrates obtained from the compositions according to the invention.