Patent · US Expired

Processes for manufacturing flexible printed wiring boards

US6233821A · kind A · utility

6Cited by
6References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 15, 1999
Grant dateMay 22, 2001
Priority date
Expiry dateMar 15, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/24917
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The present invention aims to obtain a flexible printed wiring board with good flatness. According to the present invention, a copper-clad film 3 is formed by applying a polyamic acid solution on one surface of a copper foil 2 and thermally contracting the polyamic acid layer la so that the other surface of the copper foil 2 may form a convex surface of a curling surface to form a polyimide film 1. A polyamic acid solution is applied on the other surface of the copper foil 2 of the copper-clad film 3, and then the polyamic acid layer 5a is thermally contracted to form a protective film 5, whereby a flexible printed wiring board 10 is obtained.

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