Patent US3726677A successfully refreshed from Google Patents.
US3726677A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photopolymerisation with leuco indigo dye derivatives
Assignee: Norprint Ltd
•
Filing: 1971-02-19
•
Granted: 1973-04-10
•
Expires: 1991-02-19
Abstract
Abstract THE POLYMERISATION OF UNSATURATED COMPOUNDS CAUSED BY EXPOSURE TO LIGHT PHOTOSENSITIVE SYSTEMS IS KNOWN AND PRIOR SYSTEMS ARE DISCUSSED, THE KNOWN SENSITIVITY TO LIGHT OF LUCO DERIVATIVES OF INDIGOID DYES IS EMPLOYED TO INITIATE THE IMAGE-FORMING POLYMERISATION OF MONOMERS. THE INVENTION PROVIDES A METHOD OF FORMING A POLYMERIC RESIST BY THE IMAGE-WISE EXPOSURE OF A BASE COATED WITH A VINYL MONOMER DISPERSION CONTAINING A LEUCO SULPHURIC ESTER OF AN INDIGO OR THIO-INDIGO DYE THE FORMATION OF ETCHING RESISTS, SILK SCREEN STENCILS AND OTHER IMAGE-BEARING PRODUCTS IS DESCRIBED.
Inventors
- 👤 M Hepher
- 👤 J Sperry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:33
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/027; G03F7/028; G03F7/031; Y; Y10; Y10S; Y10S430/00; Y10S430/1053; Y10S430/1055; Y10S430/114; Y10S430/116; Y10S430/127
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-09 | 1976-10-09 | 1977-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-09 | 1980-10-09 | 1981-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-09 | 1984-10-09 | 1985-04-10 | $7700.00 | Window Closed / Lapsed |