Negative-working diazotype photoreproduction
US4252884A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 14, 1979 |
| Grant date | Feb 24, 1981 |
| Priority date | — |
| Expiry date | Aug 14, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C1/58
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Negative-working diazography material is comprised of (i) at least one diazonium compound, (ii) at least one acid labile enolic, preferably phenolic blocked-coupler adapted to be converted in the presence of acid to an active azo-coupling component, and (iii) at least one light-sensitive acid progenitor. The diazonium compound can itself concurrently function as the acid progenitor, e.g., when complexed with a Lewis acid. Upon imagewise exposure to light, acid catalyst is photochemically liberated, thus unblocking coupler molecules such that dye image forms under alkaline developing conditions only where the material has been irradiated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.