Method of making an electro-discharge electrode
US4020535A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 1975 |
| Grant date | May 3, 1977 |
| Priority date | — |
| Expiry date | Aug 1, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/0117
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Method of forming an electrode for imprinting or imaging a circuit board mold face includes covering a graphite substrate with a photoresist material. The photoresist material is appropriately exposed to develop a desired pattern. The unpolymerized photoresist is removed from the graphite substrate to leave the desired pattern of an exposed graphite surface. The graphite substrate is then impacted by a dry air blast of glass beads having a size in the range of approximately 200 to 325 mesh. The glass beads will remove a desired amount of graphite to thereby cut the desired pattern into the substrate but will not remove the photoresist or affect the substrate beneath the polymerized photoresist. The polymerized photoresist is removed with materials that will not interfere with the subsequent machining process. The resultant cut graphite substrate can be utilized as a electrode in an electrical discharge machining process to form a desired pattern in a mold face.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.