Process of developing posi-type lithographic printing plate with inorganic alkali solution
US4467027A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 1982 |
| Grant date | Aug 21, 1984 |
| Priority date | — |
| Expiry date | May 20, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/322
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A developer composition of an alkaline aqueous solution containing a reducing inorganic salt, typically an alkali metal salt of sulfurous acid such as sodium sulfite, is found to be applicable for development of a lithographic printing plate material containing a photosensitive o-quinonediazide compound and an organic polymer, with reduced deterioration in developing capacity caused by the air and enhanced stability with lapse of time. In particular, a developer composition composed of an alkaline aqueous solution of pH 11 or higher containing a water-soluble sulfurous acid salt is effective for developing both of a lithographic printing plate material having a nega-type photosensitive layer containing a photosensitive diazo compound and an organic polymer, and a lithographic printing plate material having a posi-type photosensitive layer containing an o-quinonediazide compound and an organic polymer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.