Patent · US Expired

Flexible copper/polyimide and barbituric acid modified bismaleimide blend/polyimide laminate

US5372891A · kind A · utility

4Cited by
5References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 16, 1992
Grant dateDec 13, 1994
Priority date
Expiry dateDec 16, 2012

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31721
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

An improved polyimide-based coating composition comprising a polyimide upper layer and a polyimide-modified bismaleimide lower layer for use as a coating on metal substrate, such as an electrolytic copper foil. The polyimide are prepared from reactions between diamines, such as p-phenylene diamine and 4-4'-diaminodiphenyl ether, and dianhydrides, such as 3,3',4,4'-benzophenone tetracarboxylic dianhydride and biphenyl-3,3',4,4'-tetracarboxylic dianhydride. The modified bismaleimide can be prepared from reacting an N,N',4,4'-diphenyl bismaleimide with a barbituric acid or its derivative. A double-layered extrusion coating technique having a double-layered extrusion die is utilized to apply the coating composition onto the metal substrate. The final laminated products show improved peel strength between the polyimide coating and the substrate, as well as improved dimensional stability and surface flatness thereof.

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