Patent US3841877A successfully refreshed from Google Patents.
US3841877A
Expired / Lapsed
US
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Development of exposed photographic silver halide elements
Assignee: Agfa Gevaert NV
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Filing: 1972-11-03
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Granted: 1974-10-15
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Expires: 1992-11-03
Abstract
Abstract A method is described of developing an exposed photographic silver halide material in an alkaline medium in the presence of a 2,3- or 2,5-dihydroxyphenylbenzotriazole. Upon development, development inhibiting benzotriazole compounds are released at the site of exposure. The method is particularly suitable for the development of photographic colour elements to reduce the contrast and for the development of emulsions of the Lippmanntype to reduce distortions of closely adjacent image details, to promote image-sharpness and to reduce yellow staining upon reversal processing.
Inventors
- 👤 J Willems
- 👤 A Vandenberghe
- 👤 R Pollet
- 👤 R Roosen
- 👤 H Philippaerts
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:00
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/305; G03C1/00; G03C1/005; G03C1/06; G03C1/34; Y; Y10; Y10S; Y10S430/00; Y10S430/156; Y10S430/158
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
35 words
A METHOD OF PRODUCING A PHOTOGRAPHIC IMAGE, WHICH COMPRISES DEVELOPING AN IMAGE-WISE EXPOSED PHOTOGRAPHIC MATERIAL HAVING A SUPPORT BEARING A SILVER HALIDE EMULSION LAYER, IN AN ALKALINE MEDIUM IN THE PRESENCE OF A 2,3-OR 2,5-DIHYDROXYPHENYLBEBZOTRIAZOLE.
Claim 2
Independent Claim
35 words
A METHOD OF PRODUCING A PHOTOGRAPHIC IMAGE, WHICH COMPRISES DEVELOPING AN IMAGE-WISE EXPOSED PHOTOGRAPHIC MATERIAL HAVING A SUPPORT BEARING A SILVER HALIDE EMULSION LAYER, IN AN ALKALINE MEDIUM IN THE PRESENCE OF A 2,3-OR 2,5-DIHYDROXYPHENYLBEBZOTRIAZOLE.
Claim 3
Dependent Claim
24 words
A method according to claim 1, wherein the 2,3- or 2,5-dihydroxyphenylbenzotriazole is incorporated in a water-permeable layer on the emulsion side of the support.
Claim 4
Dependent Claim
17 words
A method according to claim 2, wherein the said water-permeable layer is a silver halide emulsion layer.
Claim 5
Dependent Claim
15 words
A method according to claim 1, wherein the alkaline medium comprises a black-and-white developing agent.
Claim 6
Dependent Claim
13 words
A method according to claim 4, wherein the said developing agent is hydroquinone.
Claim 7
Dependent Claim
27 words
A method according to claim 1, wherein the said emulsion comprises a colour forming coupler and the alkaline medium comprises an aromatic primary amino colour developing agent.
Claim 8
Dependent Claim
25 words
A method according to claim 1, wherein the said emulsion layer is a Lippmann emulsion the average grain-size of which is less than 100 nm.
Claim 9
Dependent Claim
25 words
A method according to claim 7, wherein the ratio of silver halide to hydrophilic colloid binder in the Lippmann-emulsion is comprised between 1:2 and 4:1.
Claim 10
Dependent Claim
28 words
A method according to claim 7, wherein the Lippmann emulsion is a silver bromide emulsion, which may have a silver iodide content of at most 8 mole percent.
Claim 11
Dependent Claim
29 words
A photographic material comprising a support bearing a silver halide emulsion layer, there being incorporated in a water-permeable layer on the emulsion side of the support a 2,3-or 2,5-dihydroxyphenylbenzotriazole.
Claim 12
Dependent Claim
29 words
A photographic material comprising a support bearing a silver halide emulsion layer, there being incorporated in a water-permeable layer on the emulsion side of the support a 2,3-or 2,5-dihydroxyphenylbenzotriazole.
Claim 13
Dependent Claim
19 words
A photographic material according to claim 10, wherein the 2,3- or 2,5-dihydroxyphenylbenzotriazole is incorporated in the said emulsion layer.
Claim 14
Dependent Claim
17 words
A photographic material according to claim 10, wherein the said emulsion layer comprises a colour forming coupler.
Claim 15
Dependent Claim
28 words
A photographic material according to claim 11, wherein the said emulsion layer is a Lippmann-emulsion layer having an average silver halide grain size of less than 100 nm.
Claim 16
Dependent Claim
27 words
A photographic material according to claim 13, wherein the ratio of silver halide to hydrophilic colloid binder in the Lippmann emulsion is comprised between 1:2 and 4:1.
Claim 17
Dependent Claim
29 words
A photographic material according to claim 13, wherein the Lippmann emulsion is a silver bromide emulsion, which may have a silver iodide content of at most 8 mole percent.
Claim 18
Dependent Claim
16 words
A photographic material according to claim 13, wherein the Lippmann-emulsion is coated on a glass support.
Claim 19
Dependent Claim
27 words
A photographic material according to claim 15, wherein the ratio of silver halide to hydrophilic colloid binder in the Lippmann emulsion is comprised between 1:2 and 4:1.
References Cited (Backward Citations)
US3246988A
Cited
US3295978A
Cited
US3379529A
Cited
US3615522A
Cited
US3493539A
Cited
US3756821A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |