Process for the production of water-soluble or water-dispersible blocked polyisocyanates

US4098933A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Tilo Burkhardt · Leverkusen, DE
• Kuno Wagner · Leverkusen, DE
• Kurt Findeisen · Odenthal, DE

Key dates

• Filing date: Nov 10, 1975
• Grant date: Jul 4, 1978
• Expiry date: Nov 10, 1995

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/8061
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

This invention relates to a process for producing stable water dispersible blocked polyisocyanates, the compounds so produced and their use in producing coatings and films. These compounds are produced by blocking about 50 to 99.8 weight % of the isocyanate groups of an organic polyisocyanate and then reacting the partially blocked polyisocyanate with a compound carrying both an isocyanate reactive hydrogen and a hydrophilic group, e.g. a carboxylic acid salt or polyethylene oxide or a group convertible to a hydrophilic group, e.g. a carboxylic acid or tertiary amine. The blocked polyisocyanate with hydrophilic groups may then be dispersed in water with organic compounds having at least two isocyanate reactive hydrogen atoms per molecule and then cured by driving off the water and raising the temperature sufficiently high to unblock the polyisocyanate.