US4609609A
Expired / Lapsed
US
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UV-absorbent compounds, process for their preparation and their use as image dyes in photographic materials for the silver dye bleach process
Assignee: Ilford Imaging Switzerland GmbH
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Filing: 1985-07-19
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Granted: 1986-09-02
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Expires: 2005-07-19
Abstract
Abstract Compounds of the formula (B--L).sub.m A--L'--B').sub.n (1), in which A is the radical of a bisazo or trisazo dye, L and L' are organic radicals and B and B' are cyclic organic radicals and at least one of the radicals B and B' has spectral absorption in the UV region and one of the radicals B and B' is different from 2,4-dihydroxyphenyl, m is 1 or 2 and n is 0, 1 or 2. The compounds are suitable for use as image dyes in photographic silver dye bleach materials.
Inventors
- 👤 Thomas-Markus Rohr
- 👤 Jakob Kuhn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 01:06
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/28; G03C7/29; C; C09; C09B; C09B35/00; C09B35/02; C09B35/38; Y; Y10; Y10S; Y10S534/00; Y10S534/01
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
114 words
Photographic silver dye bleach material which contains in at least one silver halide emulsion layer or in a layer adjacent to it, a compound of the formula (B--L).sub.m A--L'--B').sub.n ( 1) in which A is the radical of a bisazo or trisazo dye, L and L' are identical or different from each other and denote bridge members, B and B' are identical or different from each other and denote aromatic radicals, at least one of the radicals B and B' having spectral absorption in the UV region, and m is 1 or 2 and n is 0, 1 or 2, provided that if n is 0, B has spectral absorption in the UV region.
Claim 2
Dependent Claim
114 words
Photographic silver dye bleach material which contains in at least one silver halide emulsion layer or in a layer adjacent to it, a compound of the formula (B--L).sub.m A--L'--B').sub.n ( 1) in which A is the radical of a bisazo or trisazo dye, L and L' are identical or different from each other and denote bridge members, B and B' are identical or different from each other and denote aromatic radicals, at least one of the radicals B and B' having spectral absorption in the UV region, and m is 1 or 2 and n is 0, 1 or 2, provided that if n is 0, B has spectral absorption in the UV region.
Claim 3
Dependent Claim
14 words
Photographic silver dye bleach material according to claim 1, which is a monochromic material.
Claim 4
Dependent Claim
59 words
A process for the preparation of copies of a diazo-type method which comprises exposing onto a diazotype material by means of UV light or light having a high UV content, as an original, a photographic image prepared with the photographic silver dye bleach material according to claim 1 by imagewise exposure, silver development, dye and silver bleaching and fixing.
References Cited (Backward Citations)
US3533799A
Cited
US3585039A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-09-01 | 1990-03-03 | 1990-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-01 | 1994-03-03 | 1994-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-01 | 1998-03-03 | 1998-09-02 | $7700.00 | Window Closed / Lapsed |