Acidic photosensitive relief image-forming materials with indicator pigment or dye
US4578341A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 3, 1984 |
| Grant date | Mar 25, 1986 |
| Priority date | — |
| Expiry date | Aug 3, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/105
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A relief image-forming composition having an acidic pH comprises a photosensitive component and an indicator capable of existing in two states differing in actinic opacity dependent upon pH. A relief image is formed by (1) exposing to light selected areas of a layer of the composition, the indicator being in its state of lower actinic opacity, (2) removing layer material from the exposed areas or from the unexposed areas and (3) shifting the pH in the remaining layer material to a value at which the indicator exists in its state of higher actinic opacity. The resultant image can then be used as an intermediate original in diazotype copying processes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.