US4383022A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diffusion transfer film unit with protective layer of water soluble copper salt, chitosan and gelatin
Assignee: Polaroid Corp
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Filing: 1982-06-28
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Granted: 1983-05-10
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Expires: 2002-06-28
Abstract
Abstract A silver diffusion transfer film unit which comprises, in order, a support carrying a silver precipitating layer, a protective layer comprising chitosan having a copper salt and gelatin disposed therein, a release layer and a photosensitive silver halide layer. In a particularly preferred embodiment, the film unit is an additive color diffusion transfer film unit.
Inventors
- 👤 Michael Berger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:38
CPC Classifications
G; G03; G03C; G03C8/00; G03C8/02; G03C8/04; G03C8/06
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
57 words
A silver diffusion transfer film unit which comprises a support carrying, in order, a layer comprising silver precipitating nuclei; a protective layer comprising a water soluble copper salt, chitosan and gelatin wherein said gelatin is at least about 11/2 times, by weight, of the level of chitosan; a release layer; and a photosensitive silver halide emulsion layer.
Claim 2
Dependent Claim
57 words
A silver diffusion transfer film unit which comprises a support carrying, in order, a layer comprising silver precipitating nuclei; a protective layer comprising a water soluble copper salt, chitosan and gelatin wherein said gelatin is at least about 11/2 times, by weight, of the level of chitosan; a release layer; and a photosensitive silver halide emulsion layer.
Claim 3
Dependent Claim
11 words
The film unit of claim 1 wherein said support is transparent.
Claim 4
Dependent Claim
11 words
The film unit of claim 1 wherein said support is opaque.
Claim 5
Dependent Claim
12 words
The film unit of claim 2 which includes an additive color screen.
Claim 6
Dependent Claim
13 words
The film unit of claim 1 wherein said copper salt is copper acetate.
Claim 7
Dependent Claim
45 words
The film unit of claim 1 wherein copper ion from said copper salt ranges from about 0.1 to 4 mg/ft 2 ; said chitosan ranges from about 1 to 13 mg/ft 2 ; and said gelatin ranges from about 2 to 20 mg/ft 2 .
Claim 8
Dependent Claim
21 words
The film unit of claim 6 wherein the ratio of chitosan to copper ion is about 10 to 1, by weight.
Claim 9
Dependent Claim
14 words
The film unit of claim 1 which includes a layer containing an antihalation compound.
Claim 10
Dependent Claim
15 words
The film unit of claim 1 wherein said silver precipitating nuclei are noble metal nuclei.
Claim 11
Dependent Claim
12 words
The film unit of claim 9 wherein said nuclei are palladium nuclei.
Claim 12
Dependent Claim
108 words
A photographic process which comprises the steps of: (a) exposing a film unit which comprises a support carrying, in order, a layer comprising silver precipitating nuclei; a protective layer comprising a water soluble copper salt, chitosan and gelatin said gelatin being at least about 11/2 times, by weight, of the level of chitosan; a release layer; and a photosensitive silver halide emulsion layer; (b) contacting said exposed film unit with a processing composition containing a silver halide developing agent and a silver halide solvent adapted to provide a positive silver image in said layer comprising silver precipitating nuclei; and (c) detaching said emulsion subsequent to positive image formation.
Claim 13
Dependent Claim
108 words
A photographic process which comprises the steps of: (a) exposing a film unit which comprises a support carrying, in order, a layer comprising silver precipitating nuclei; a protective layer comprising a water soluble copper salt, chitosan and gelatin said gelatin being at least about 11/2 times, by weight, of the level of chitosan; a release layer; and a photosensitive silver halide emulsion layer; (b) contacting said exposed film unit with a processing composition containing a silver halide developing agent and a silver halide solvent adapted to provide a positive silver image in said layer comprising silver precipitating nuclei; and (c) detaching said emulsion subsequent to positive image formation.
Claim 14
Dependent Claim
10 words
The process of claim 11 wherein said support is transparent.
Claim 15
Dependent Claim
10 words
The process of claim 11 wherein said support is opaque.
Claim 16
Dependent Claim
14 words
The process of claim 12 herein said film unit includes an additive color screen.
Claim 17
Dependent Claim
12 words
The process of claim 11 wherein said copper salt is copper acetate.
Claim 18
Dependent Claim
44 words
The process of claim 11 wherein said copper ion from copper salt ranges from about 0.1 to 4 mg/ft 2 ; said chitosan ranges from about 1 to 13 mg/ft 2 ; and said gelatin ranges from about 2 to 20 mg/ft 2 .
Claim 19
Dependent Claim
20 words
The process of claim 16 wherein the ratio of chitosan to copper ion is about 10 to 1 by weight.
Claim 20
Dependent Claim
16 words
The process of claim 11 wherein said emulsion layer is removed subsequent to positive image formation.
Claim 21
Dependent Claim
16 words
The process of claim 11 wherein said film unit includes a layer containing an antihalation compound.
References Cited (Backward Citations)
US3674482A
Cited
US4056392A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-05-09 | 1986-11-08 | 1987-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-09 | 1990-11-08 | 1991-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-09 | 1994-11-08 | 1995-05-10 | $7700.00 | Window Closed / Lapsed |