US4017314A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Use of crown compounds (cyclic polyethers) in litho developers to improve halftone dot quality and gradation
Assignee: EIDP Inc
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Filing: 1976-01-07
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Granted: 1977-04-12
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Expires: 1996-01-07
Abstract
Abstract A photographic developer for high contrast lithographic films comprising a conventional hydroquinone formaldehyde bisulfite developer and a crown compound (cyclic polyether) e.g. dibenzo-30-crown-10.
Inventors
- 👤 Ralph Kingsley Blake, deceased
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:13
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/305
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
38 words
The process of developing a silver halide image with a photographic developer solution containing a silver halide photographic developing agent and a crown compound having 5-16 oxygen atoms in a cyclic ring having a total of 14-60 atoms.
Claim 2
Dependent Claim
38 words
The process of developing a silver halide image with a photographic developer solution containing a silver halide photographic developing agent and a crown compound having 5-16 oxygen atoms in a cyclic ring having a total of 14-60 atoms.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein said developer solution is an aqueous alkaline photographic developer solution.
Claim 4
Dependent Claim
66 words
A process for the production of developed photographic material which comprises subjecting photographic lith material containing a latent silver image in a silver halide emulsion layer to development by means of a formaldehyde/bisulphite/hydroquinone lithographic developer, the process being characterized in that the development takes place in the presence of a crown compound having 5-16 oxygen atoms in a cyclic ring having a total of 14-60 atoms.
Claim 5
Dependent Claim
66 words
A process for the production of developed photographic material which comprises subjecting photographic lith material containing a latent silver image in a silver halide emulsion layer to development by means of a formaldehyde/bisulphite/hydroquinone lithographic developer, the process being characterized in that the development takes place in the presence of a crown compound having 5-16 oxygen atoms in a cyclic ring having a total of 14-60 atoms.
Claim 6
Dependent Claim
21 words
The process of claim 3 wherein the crown compound is employed in an amount of 1-100 mgs. per liter of developer.
Claim 7
Dependent Claim
11 words
The process of claim 3 wherein said crown compound is dibenzo-18-crown-6.
Claim 8
Dependent Claim
11 words
The process of claim 3 wherein said crown compound is dibenzo-30-crown-10.
Claim 9
Dependent Claim
29 words
An aqueous developer solution containing a silver halide photographic developing agent and a crown compound having 5-16 oxygen atoms in a cyclic ring having a total of 14-60 atoms.
Claim 10
Dependent Claim
29 words
An aqueous developer solution containing a silver halide photographic developing agent and a crown compound having 5-16 oxygen atoms in a cyclic ring having a total of 14-60 atoms.
Claim 11
Dependent Claim
42 words
A photographic developer capable of producing high contrast images upon photographic development comprising a developing solution containing a p-dihydroxybenzene developing agent, a sulfite buffer, and a crown compound having 5-16 oxygen atoms in a cyclic ring having a total of 14-60 atoms.
Claim 12
Dependent Claim
42 words
A photographic developer capable of producing high contrast images upon photographic development comprising a developing solution containing a p-dihydroxybenzene developing agent, a sulfite buffer, and a crown compound having 5-16 oxygen atoms in a cyclic ring having a total of 14-60 atoms.
Claim 13
Dependent Claim
11 words
The developer of claim 8 wherein said crown compound is dibenzo-18-crown-6.
Claim 14
Dependent Claim
11 words
The developer of claim 8 wherein said crown compound is dibenzo-30-crown-10.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-04-11 | 1980-10-11 | 1981-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-04-11 | 1984-10-11 | 1985-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-04-11 | 1988-10-11 | 1989-04-12 | $7700.00 | Window Closed / Lapsed |