US4309499A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Formation of black-and-white silver-containing negative images by a diffusion transfer process
Assignee: Fujifilm Holdings Corp
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Filing: 1979-11-14
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Granted: 1982-01-05
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Expires: 1999-11-14
Abstract
Abstract A black-and-white negative image forming process is disclosed using a diffusion transfer type film unit. An exposed silver halide emulsion comprising internal latent image type silver halide grains which have substantially no fogging centers at their surface is processed with a composition comprising a silver halide solvent, a developing agent, a foggant, alkali and a fog promoting agent. The solvent for the silver halide characteristically possesses a solubilizing power for AgBr of from about 2×10 -5 to 5×10 -3 mol/l in a 0.002 molar aqueous solution.
Inventors
- 👤 Yoshihiro Takagi
- 👤 Katsumi Hayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:55
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/485; G03C1/48538; G03C8/00; G03C8/02; G03C8/04; G03C8/06
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
132 words
In a method of fogging black-and-white silver-containing negative images by a diffusion transfer photographic process using a black-and-white diffusion transfer photographic film unit comprising a plastic support, a silver halide photographic emulsion layer and an image-receiving layer which unit is imagewise exposed, the improvement which comprises subsequent processing in a single processing solution comprising a solvent for the silver halide, a foggant, a developing agent and a fogging promoting agent, whereby an optically negative image develops in said image-receiving layer, said silver halide photographic emulsion being an internal latent image type emulsion having no surface fog centers, and said silver halide solvent having a solubility for silver bromide as a 0.02 molar aqueous solution of about 2×10 -5 to 5 a 10 -3 mol/l at 60° C. and at the developing pH.
Claim 2
Dependent Claim
132 words
In a method of fogging black-and-white silver-containing negative images by a diffusion transfer photographic process using a black-and-white diffusion transfer photographic film unit comprising a plastic support, a silver halide photographic emulsion layer and an image-receiving layer which unit is imagewise exposed, the improvement which comprises subsequent processing in a single processing solution comprising a solvent for the silver halide, a foggant, a developing agent and a fogging promoting agent, whereby an optically negative image develops in said image-receiving layer, said silver halide photographic emulsion being an internal latent image type emulsion having no surface fog centers, and said silver halide solvent having a solubility for silver bromide as a 0.02 molar aqueous solution of about 2×10 -5 to 5 a 10 -3 mol/l at 60° C. and at the developing pH.
Claim 3
Dependent Claim
63 words
The method of claim 1, wherein said internal latent image silver halide is a silver halide which provides a maximum density when developed at 20° C. for 3 minutes with Developer A defined in the specification which is more than 5 times greater than the maximum density obtained when developed at 20° C. for 4 minutes with Developer B defined in the specification.
Claim 4
Dependent Claim
35 words
The method of claim 1, wherein said silver halide solvent has a solubility for silver bromide when used as a 0.02 molar aqueous solution of about 5×10 -5 to 2×10 -3 mol/l at 60° C.
Claim 5
Dependent Claim
40 words
The method of claim 1, wherein said fogging promoting agent is selected from the group consisting of a triazole, an indazole, a triazaindolidine, an imidazole, an oxazole, a pyrimidine, a pyrazole, a pyrazolone, a thiazole, an amine and a thiadiazole.
Claim 6
Dependent Claim
12 words
The method of claim 4, wherein said fogging promoting agent comprises 5-methylbenzotriazole.
Claim 7
Dependent Claim
13 words
The method of claim 1, wherein said silver halide solvent is a thioether.
Claim 8
Dependent Claim
21 words
The method of claim 1, wherein said silver halide solvent is used in an amount of about 1 to 60 g/l.
Claim 9
Dependent Claim
21 words
The method of claim 1, wherein said developer is a dihydroxybenzene, a 3-pyrazolidone, an aminophenol, a hydroxyamine, or a mixture thereof.
Claim 10
Dependent Claim
11 words
The method of claim 8, wherein said developer is a dihydroxybenzene.
Claim 11
Dependent Claim
18 words
The method of claim 1, wherein said method is carried out in a peel-apart diffusion transfer photographic material.
Claim 12
Dependent Claim
19 words
The method of claim 1, wherein said method is carried out in an integral diffusion transfer photographic film unit.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-01-04 | 1985-07-06 | 1986-01-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-01-04 | 1989-07-06 | 1990-01-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-01-04 | 1993-07-06 | 1994-01-05 | $7700.00 | Window Closed / Lapsed |