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US3790388A Expired / Lapsed US ⏱️ 0.0 years remaining

Direct positive color photographic materials

Assignee: Fujifilm Holdings Corp
•
Filing: 1972-09-13
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Granted: 1974-02-05
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Expires: 1992-09-13
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Abstract

Abstract A direct positive color photographic material having a silver halide photographic emulsion layer containing chemically fogged silver halide grains, said silver halide emulsion layer containing a magenta color coupler precursor having a pyrazole nucleus substituted by an acyloxy group at the five-position. The direct positive color photographic material containing such a magenta color coupler precursor has a high sensitivity, shows good clearness in the highlight portions, and has improved stability.

Inventors

  • 👤 K Shiba
  • 👤 S Kubodera
  • 👤 K Sano
  • 👤 A Okumura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 15:06
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/485; G03C1/48515; C; C07; C07D; C07D231/00; C07D231/02; C07D231/10; C07D231/14; C07D231/44; C07D231/52; G03C7/00; G03C7/30; G03C7/32; G03C7/36; G03C7/38; G03C7/384; Y; Y10; Y10S; Y10S430/00; Y10S430/156

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 160 words
The color photographic material as set forth in claim 1, wherein said silver halide emulsion has the following characteristics: 1. Dmin (b) 0.3 X Dmax (a) and 2. Sb < or = 0.65 X Sa wherein Dmin (b) is the minimum optical density of the silver halide emulsion coated on a test strip, subjected to a vacuum of below 10 4 mmHg for more than 17 hours, exposed to a blue light through an optical wedge under said vacuum and developed, wherein Dmax (a) is the maximum optical density of the silver halide emulsion coated on a test strip, exposed to a blue light through an optical wedge and at normal pressures and developed, wherein Sa is the sensitivity of the silver halide emulsion at said maximum optical density obtained at normal pressures, wherein Sb is the sensitivity of the silver halide emulsion at 1/2 of the maximum optical density of the silver halide emulsion evaluated at under said vacuum.
Claim 2
Dependent Claim 22 words
The color photographic material as set forth in claim 1, wherein said color coupler precursor is a compound represented by the formula
Claim 3
Dependent Claim 22 words
The color photographic material as set forth in claim 1, wherein said color coupler precursor is a compound represented by the formula
Claim 4
Dependent Claim 42 words
The color photographic material as set forth in claim 1, wherein said silver halide grains of said silver halide photographic emulsion have adsorbed thereon an electron acceptor having at least one of a sulfo group, a carboxyl group, or a phosphate group.
Claim 5
Dependent Claim 58 words
The color photographic material as set forth in claim 1, wherein the silver halide grains of said silver halide photographic emulsion have adsorbed thereon an electron acceptor having at least one of a sulfo group, a carboxyl group, or a phosphate group and a halogen acceptor having at least one of a sulfo group or a carboxyl group.
Claim 6
Dependent Claim 41 words
The color photographic material as set forth in claim 1, wherein said silver halide grains are chemically fogged using stannous chloride, sodium borohydride, cuprous chloride, hydrazine, a hydrazine derivative, formalin, thiourea dioxide, a polyamino compound, an amine borane, or methyl dichlorosilane.
Claim 7
Dependent Claim 29 words
The color photographic material of claim 1, wherein said emulsion is a gelatin emulsion and wherein said silver halide is silver chloride, silver bromide, silver iodide, or mixtures thereof.
Claim 8
Dependent Claim 40 words
The color photographic material as set forth in claim 6, wherein said electron acceptor and said halogen acceptor are present at a level of from 1 X 10 6 to 5 X 10 3 mole per mole of silver halide.
Claim 9
Dependent Claim 21 words
A color photographic element comprising a support having thereon at least one layer of the color photographic material of claim 1.

References Cited (Backward Citations)

US2436130A Cited
US2706685A Cited
US3501307A Cited
US3501312A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-02-04 1977-08-06 1978-02-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-02-04 1981-08-06 1982-02-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-02-04 1985-08-06 1986-02-05 $7700.00 Window Closed / Lapsed

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