Aqueous dispersion of polyurethanes containing siloxane linkages, production thereof and use in coating compositions

US5760123A · kind A · utility

Assignee

• Herberts Gesellschaft mit beschrankter Haftung · DE

Inventors

• Bettina Vogt-Birnbrich · Solingen, DE
• Hans-Peter Patzschke · Wuppertal, DE
• Werner Lenhard · Wuppertal, DE
• Jurgen Dobert · Sprockhövel, DE
• Marcus Brunner · Wuppertal, DE

Key dates

• Filing date: Feb 13, 1996
• Grant date: Jun 2, 1998
• Expiry date: Feb 13, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/5042
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Aqueous dispersion of one or more polyurethane resins with a number average molecular weight (Mn) of 2500 to 1000000, a content of 2 to 150 mmol of siloxane linkages (--Si--O--Si--) per 100 g of solid resin, a hydroxyl value of 0 to 100 and a content of ionic groups, groups convertible into ionic groups and/or hydrophilic groups of 5 to 200 mEq per 100 g of solid resin and the process for the production thereof by chain extension of a polyurethane prepolymer containing ionic groups, groups capable of ion formation and/or hydrophilic groups which has at least one group R'OSi-- in which PA1 R'=C.sub.1 to C.sub.8 alkyl or C(O)R"' and PA1 R"'=C.sub.1 to C.sub.10 alkyl by the addition of water. The aqueous dispersion is suitable for aqueous coating compositions which are suitable in particular for multilayer lacquer coatings.