Method of producing multilayer circuit boards
US5681485A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 1995 |
| Grant date | Oct 28, 1997 |
| Priority date | — |
| Expiry date | Nov 30, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2201/0209
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of producing multilayer circuit boardschar comprising repeating a procedure comprising the steps of (1) laminating a photosensitive film composition shaped in a film form onto an insulating material carrying a conductor pattern formed thereon, (2) exposing the laminated photosensitive film composition to light through a negative type photomask, (3) dissolving the domains not irradiated in the above exposure step, (4) heat-curing the domains not dissolved in step (3), (5) forming a copper plating layer on the surface of the photosensitive film composition heat-cured in step (4) by electroless copper plating with or without further electroplating of copper, and (6) forming, on the plated copper layer formed in step (5), a photosensitive etch resist layer and subjecting said layer to light exposure through a photomask having a circuit pattern drawn thereon, developing and etching to thereby form a conductor pattern, said photosensitive film composition for lamination containing at least 50% by weight of a bisphenol-epichlorohydrin type resin containing photosensitive functional groups and heat-curable functional groups.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.