Process for preparing printed-circuit board
US5236810A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1990 |
| Grant date | Aug 17, 1993 |
| Priority date | — |
| Expiry date | Oct 3, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/135
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An improved process for preparing a printed-circuit board, which successively comprises (I) a step of forming a positive photo-sensitive resist film onto a circuit board having a conductive film according to the electrodeposition coating process, (II) a step of irradiating a full dose of an actinic ray onto the positive photo-sensitive resist film through a photomask with which the actinic ray is cut off over a conductive circuit-forming area, (III) a step of developing the resulting resist film, (IV) a step of etching away a deposited copper-clad area, and (V) removing a remaining resist film on the conductive circuit-forming area, the improvement further comprising a step of imparting the resist film in the conductive circuit-forming area an increased alkali resistance prior to development so as to obtain the printed-circuit board having high resolution with good reproductivity without being affected by variations of the developing conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.