Coatings for thermoplastics

US4315091A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Helmut Steinberger · Leverkusen, DE
• Manfred Schonfelder · Leverkusen, DE
• Hans-Heinrich Moretto · Cologne, DE
• Christian Wegner · Cologne, DE

Key dates

• Filing date: Apr 7, 1980
• Grant date: Feb 9, 1982
• Expiry date: Apr 7, 2000

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31663
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

A coating composition to improve the abrasion and scratch resistance of plastics such as polycarbonate, consisting essentially of about PA0 (A) 10-40% by weight of a partially hydrolyzed siloxane compound which is obtained by hydrolyzing in water at about 50.degree.-80.degree. C. over a period of about 1-12 hours at least one of PA1 (a) a hydrocarbon-trialkoxysilane of the formula R'Si(OR").sub.3 wherein PA2 R' is an alkyl group with 1 to 4 carbon atoms or a phenyl or vinyl group, and PA2 R" is an alkyl group with 1 to 4 carbon atoms, PA1 (b) a co-condensation product of (a) and about 1 to 40% by weight of a phenyl- or vinyl-trialkoxysilane, the alkoxy group containing 1 to 4 carbon atoms, PA1 (c) a co-condensation product of 1 mol of (a) and 0.05 to 1 mol of a tetraalkoxysilane, in which the alkoxy group contains 1 to 4 carbon atoms, and PA1 (d) a co-condensation product of 1 mol of (a) and 0.05 to 1 of a dialkyldialkoxysilane, in which the alkyl and alkoxy groups contain 1 to 4 carbon atoms. PA0 (B) 0 to 40% by weight of an aqueous dispersion of colloidal silicon dioxide, PA0 (C) 0 to 5% by weight of an etherified methylolmelamine, PA0 (D) 0.05 to 15% by weight of a blocked polyi…