Polyurethane dispersions and their use as binders in stoving lacquers

US5563206A · kind A · utility

Assignee

• Henkel Kommanditgesellschaft auf Aktien · DE

Inventors

• Ulrich Eicken · Korschenbroich, DE
• Alfred Westfechtel · Hilden, DE
• Rainer Hoefer · Goldkronach, DE
• Roland Gruetzmacher · Wülfrath, DE

Key dates

• Filing date: May 11, 1995
• Grant date: Oct 8, 1996
• Expiry date: May 11, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/3212
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Aqueous polyurethane dispersions prepared in several stages by reacting PA1 A) aliphatic and/or aromatic di- and/or tri-isocyanates with PA1 B1) polyol mixtures containing dimer diols of 25 to 100% by weight of dimer diols and 0 to 75% by weight of other hydrophobic diols and/or polyols, the equivalent ratio of OH to NCO being 1:1.1 to 1:4, and simultaneously or subsequently with PA1 B2) chain-extending agents containing two terminal NCO-reactive groups, the chain-extending agents additionally containing either artionic or cationic groups or groups convertible into anionic or cationic groups by neutralization, the equivalent ratio of NCO-reactive groups to NCO groups theoretically still present after the reaction of A) with B1) being 1:0.9 to 1:4, and then optionally reacting PA1 C) the NCO groups theoretically still present in the polyurethanes after the reaction of A) with B1) and B2) with polyols containing at least three hydroxyl groups and/or amino alcohols containing at least two hydroxyl groups in an equivalent ratio of OH+amino groups to NCO of at least 3:1, and finally dispersing the polyurethanes obtained in water, the polyurethanes obtained being at least partly neutrali…