Photographic printing plate for use in a vacuum printing frame
US4656107A · kind A · utility
7Cited by
17References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 23, 1985 |
| Grant date | Apr 7, 1987 |
| Priority date | — |
| Expiry date | Dec 23, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/162
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for exposing a layer of photoresist on a sheet includes positioning the sheet in a vacuum printing frame comprising a glass plate carrying an opaque master pattern of metal or metal oxide. With the pattern opposite the coating, the frame is evacuated and the layer is exposed. The pattern has a substantially-uniform thickness in the range of about 0.5.+-.0.2 micrometer. To reduce the times for evacuating and devacuating the frame, the pattern side of the glass plate carries an array of light-transparent islands up to about 3.0-micrometer thick. An overcoating of wax on the islands is a further aid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.