Blocked polyurethane prepolymers useful in coating compositions

US7019102B2 · kind B2 · utility

Assignee

• Henkel Kommanditgesellschaft auf Aktien · DE

Inventors

• Rainer Schoenfeld · Goldkronach, DE
• Corina Bisog · Franklin, US
• David Sturgill · Brookfield, US
• Kazuhiko Sato · Mito, JP

Key dates

• Filing date: Jun 18, 2004
• Grant date: Mar 28, 2006
• Expiry date: Aug 17, 2024

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G2350/00
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Blocked polyurethane prepolymers obtained by reacting at least one polyol, a first polyisocyanate comprising diphenylmethane diisocyanate, a second polyisocyanate having a viscosity at 25° C. of less than about 250 mPa·s, a phenol blocking agent, and an oxime blocking agent, wherein the weight ratio of second polyisocyanate:first polyisocyanate is not more than 0.65:1. The blocked polyurethane prepolymers are especially useful in formulating coating compositions additionally comprising at least one acrylic resin, at least one plasticizer, at least one filler, and optionally other ingredients and additives. A cured coating is obtained by applying a layer of the coating composition to a substrate surface and heating the coating composition layer.