Polyurethanes

US6025456A · kind A · utility

Assignee

• Emtec Magnetics GmbH · DE

Inventors

• Thomas Wunsch · Speyer, DE
• Ria Kress · Ludwigshafen, DE
• Werner Loch · Erpolzheim, DE
• August Lehner
• Albert Kohl · Laumersheim, DE
• Norbert Schneider · Schorndorf, DE
• Uwe Burkhardt · Kaiserslautern, DE

Key dates

• Filing date: Mar 9, 1998
• Grant date: Feb 15, 2000
• Expiry date: Mar 9, 2018

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08L75/04
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Hydroxyl-containing polyurethanes I are composed essentially of PA1 a) a diisocyanate of 6 to 30 carbon atoms (component II), PA1 b) a component III comprising PA2 .alpha.) an aliphatic diol of 2 to 20 carbon atoms or PA2 .beta.) an aromatic-aliphatic or aromatic-cycloaliphatic diol of 8 to 30 carbon atoms having nonphenolic hydroxyl groups as hydroxyl groups of the diol and PA1 c) a polyhydric alcohol having at least 3 hydroxyl groups, 3 to 18 carbon atoms and nonphenolic hydroxyl groups as hydroxyl groups of the alcohol (component IV), the amounts of components II to IV being such that the total number of nonphenolic hydroxyl groups is from 1.1 to 5.0 per isocyanate group of II. The polyurethanes can be used as binders or binder components for pigment-containing coatings, in particular for the production of magnetic recording materials.