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US4358528A 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: 1981-06-08
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Granted: 1982-11-09
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Expires: 2001-06-08
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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 04:08
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: 15
Claim 1
Independent Claim 138 words
In a method of forming black-and-white silver-containing negative image 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 (1) processing in a single processing solution comprising a solvent for the silver halide, 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 of a 0.02 molar aqueous solution of about 2×10 -5 to 5×10 -3 mol/l at 60° C. and at the developing pH; and (2) including a foggant in said photographic film unit.
Claim 2
Dependent Claim 138 words
In a method of forming black-and-white silver-containing negative image 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 (1) processing in a single processing solution comprising a solvent for the silver halide, 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 of a 0.02 molar aqueous solution of about 2×10 -5 to 5×10 -3 mol/l at 60° C. and at the developing pH; and (2) including a foggant in said photographic film unit.
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 25 words
The method of claim 1, wherein said silver halide solvent is used as a processing fluid in an amount of about 1 to 60 g/l.
Claim 9
Dependent Claim 24 words
The method of claim 1, wherein said foggant is present in said film unit in an amount of about 50 to 1,500 mg/mol silver.
Claim 10
Dependent Claim 24 words
The method of claim 8, wherein said foggant is present in said film unit in the amount of about 300 to 600 mg/mol silver.
Claim 11
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 12
Dependent Claim 11 words
The method of claim 10, wherein said developer is a dihydroxybenzene.
Claim 13
Dependent Claim 18 words
The method of claim 1, wherein said method is carried out in a peel-apart diffusion transfer photographic material.
Claim 14
Dependent Claim 19 words
The method of claim 1, wherein said method is carried out in an integral diffusion transfer photographic film unit.
Claim 15
Dependent Claim 22 words
The method of claim 1, wherein said foggant is present in said silver halide photographic emulsion layer of said photographic film unit.

References Cited (Backward Citations)

US4030925A Cited
US4309499A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-11-08 1986-05-10 1986-11-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-11-08 1990-05-10 1990-11-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-11-08 1994-05-10 1994-11-09 $7700.00 Window Closed / Lapsed

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