Photographic reproduction processes using diazonium salts and substituted spiro[benzopyrane]
US3964911A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 18, 1973 |
| Grant date | Jun 22, 1976 |
| Priority date | — |
| Expiry date | Dec 18, 1993 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C1/61
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Photosensitive compositions which include a homogeneous mixture of PA1 A. at least one diazonium salt which is photodecomposable into phenol; PA1 B. at least one spiropyran compound which is photodecomposable into mercocyanine; and optionally PA1 C. a material which is normally solid at ambient temperatures and has a melting point no higher than about 150.degree.C and which when in the molten state is a solvent for the phenol and merocyanine compounds from (a) and (b), above. The merocyanine and phenol form colored complexes when reacted in the molten or dissolved state. The photosensitive compositions of the present invention can be used for preparing reproductions of original transparencies containing image areas and non-image transparent areas as positives or negatives thereof and in colors ranging from blue-black, blue, green, red, orange, brown and colors in between. In the formation of positive images, advantage is taken of the reversibility of the photochemical decomposition of the spiropyran compound into the merocyanine compound.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.