Cycloolefin copolymers (COCS) as substrate material for liquid-crystal displays

US5744664A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Michael-Joachim Brekner · Frankfurt am Main, DE
• Dietmar Jungbauer · Weiterstadt, DE

Key dates

• Filing date: Nov 16, 1994
• Grant date: Apr 28, 1998
• Expiry date: Nov 16, 2014

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F32/00
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A substrate for liquid-crystal displays is formed from polymers of polycyclic olefins by polymerization, without ring opening, of at least one monomer of the formula (I), (II), (III), (IV), (V) or (VI). The novel use of cycloolefin copolymers as substrate material facilitates process temperatures of above 180.degree. C. in the production of displays. Cycloolefin copolymers are lighter and less brittle than glass. Compared with other plastics, they have advantages in photoelastic constants, thermal expansion, hardness, density, transparency, water absorption and with respect to birefringence. Furthermore, they have high resistance to polar solvents.