Photoresist compositions and flexible printed wiring boards with protective layer
US6638689B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1999 |
| Grant date | Oct 28, 2003 |
| Priority date | — |
| Expiry date | Apr 8, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/111
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Photoresist compositions, which can attain high-accuracy etching without causing separation and flexible printed wiring boards prepared with the photoresist compositions are disclosed. In order to etch a polyimide precursor layer on a conductive circuit, a photoresist composition comprising a photopolymerizable organic material (A), a water-soluble resin (B) and an amino-group-containing resin (C) is applied on the surface of the polyimide precursor layer to form a photoresist layer. Then, the photoresist layer is patterned by a photolithographic process. The polyimide precursor layer is etched and the pattern of the photoresist layer is transferred to the polyimide precursor layer. The amino-group-containing resin (C) in the photoresist layer is combined with an acid anhydride in the polyimide precursor layer to attain good adhesion and high-accuracy etching without causing separation of the photoresist layer. Alternatively, a film can be formed from the photoresist composition and then be applied on the surface of the polyimide precursor layer to form a photoresist layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.