Method for applying a solder resist layer to a printed circuit board
US5134056A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1990 |
| Grant date | Jul 28, 1992 |
| Priority date | — |
| Expiry date | Dec 21, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/1105
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A solder resist and a positively-acting photoresist are successively applied on a surface-wide basis onto a printed circuit board, whereupon the photoresist is selectively exposed and developed in the region of plated-through holes and/or solder pads of a printed conductor pattern carried on the printed circuit board, preferably with the assistance of laser beams. Subsequently, the solder resist is stripped in the regions not protected by the photoresist, i.e. in the regions of plated-through holes and/or solder pads and, as a last step, the remaining photoresist is likewise stripped. The method is particularly suited for the application of a solder resist layer onto three-dimensional printed circuit boards since traditional mask techniques for structuring the solder resist cannot be employed with respect to three-dimensional printed circuit boards.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.