Patent · US Expired

Polyimide

US5830976A · kind A · utility

4Cited by
2References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 5, 1997
Grant dateNov 3, 1998
Priority date
Expiry dateAug 5, 2017

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09K2323/027
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A polyamic acid is herein disclosed which contains a structural unit represented by the formula 2a! ##STR1## wherein m is an integer of 1 to 20; n is an integer of 1 to 2; and R.sup.2 is an alkyl group or an alkoxy group having 1 to 20 carbon atoms. Furthermore, a polyamic acid composition is also disclosed which comprises the polyamic acid containing the structural unit represented by the formula 2a! and another polyamic acid containing a structural unit other than mentioned above. By heating the polyamic acid or the polyamic acid composition at a low temperature for a short time, a liquid crystal alignment film can be obtained which comprises a polyimide or a polyimide composition.

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