Coating materials containing PUR dispersions and solvents and their use for the preparation of water vapor permeable PUR coatings

US5177141A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Wilhelm Thoma · Leverkusen, DE
• Rolf Langel · Leverkusen, DE
• Walter Schroer · Leverkusen, DE

Key dates

• Filing date: Oct 16, 1989
• Grant date: Jan 5, 1993
• Expiry date: Oct 16, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09D175/04
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention is directed to coating compositions (pastes) containing PA1 a) about 20 to 90% of an aqueous polyurethane dispersion which has a solids content of about 20 to 60% and wherein the polyurethane is rendered hydrophilic by carboxylate groups, sulphonate groups, pendant polyether chains having oxyethylene units, terminal polyether chains having oxyethylene units or mixtures thereof, PA1 b) about 0.1 to 5% by weight of a water-soluble, polymeric thickening agent for aqueous polyurethane dispersions which is not a polyurethane and which is free from carboxyl groups, PA1 c) about 3 to 80% by weight of water-immiscible organic solvent which is not a solvent for polyurethanes dispersed in water and which has a boiling point up to 250 C., PA1 d) about 0.1 to 5% by weight of a cross-linking agent for the polyurethane dispersed in water which does not contain free isocyanate groups and PA1 e) about 0.1 to 5% by weight of a hydrophilic polyisocyanate which promotes the adhesion of the coating composition to substrates and is a cross-linking agent for the polyurethane dispersed in water, the sum of the percentages of a)+b)+c)+d)+e) being 100. The present invention is also di…