Patent · US Expired

Transparent abrasion-resistant coating for a styrene acrylonitrile copolymer and method

US3998991A · kind A · utility

12Cited by
6References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 29, 1974
Grant dateDec 21, 1976
Priority date
Expiry dateMar 29, 1994

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31935
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

In accordance with a preferred embodiment of this invention, a styrene-acrylonitrile copolymer (SAN) surface is coated with a weatherable, transparent and abrasion-resistant material. The film coating, which is typically less than one micron thick, is formed on a SAN surface which has been chemically activated by direct contact with a strong oxidizing agent. The coating consists essentially of the condensation reaction product of a partially hydrolyzed poly(vinyl acetate), equilibrated tetraethyl orthosilicate and a silane compound, which also acts as an adhesion promoting agent and which is selected from the group consisting of compounds with the general formula: ##EQU1## where x is from 1 to 10 and compounds with the general formula: ##EQU2## where x is from 1 to 10 and y is from 1 to 10. The trimethoxy functionality of the silane compound is initially hydrolyzed to a trisilanol functionality. Then by participating in a condensation reaction with the equilibrated silicate and the partially hydrolyzed acetate, the silane is chemically bound into the coating matrix. To complete the chemical link between the coating and the substrate, the epoxy functionality apparently reacts with t…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.