Process for the manufacture of printed circuit boards
US4529477A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 2, 1983 |
| Grant date | Jul 16, 1985 |
| Priority date | — |
| Expiry date | May 2, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2201/0959
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The process and device in accordance with the present invention allow the simple and economic manufacture of printed circuit boards, wherein the metal of the conductors as well as the one covering the hole walls is identical with the metal being etched away from the areas between the conductors. According to this process, a one-or two-sided metal-coated base material is used which, upon production of the hole pattern, is provided in a known manner with a metal layer of desired thickness, covering the surface of the metal foil as well as the hole walls. Subsequently, a masking layer is applied by screen printing a positive image of the desired circuit pattern on the surface(s). In the following process step, the holes are filled with an ink by means of a screen printing stencil. In accordance with one embodiment of the invention, the ink used forms an etch-resistant surface film when drying. Upon etching, the masking layer as well as the surface film and the hole fillings are removed with a suitable solvent. The screen printing stencil comprises a carrier screen fixed to a frame, said carrier screen being provided on its side facing the surface to be printed with a metal or plastic …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.