US3751252A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photothermographic element and process
Assignee: Eastman Kodak Co
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Filing: 1972-03-24
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Granted: 1973-08-07
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Expires: 1992-03-24
Abstract
Abstract Hydroxamic acid reducing agents in a photothermographic element or process for developing a latent image with heat provide a developed image having increased maximum density. They can be employed in an oxidation-reduction image forming combination wherein the hydroxamic acid is used as the reducing agent. Addenda employed in photothermographic elements and processes, such as activator-toning agents, sensitizing dyes and stabilizer precursors can be employed with the hydroxamic acid reducing agents.
Inventors
- 👤 G Smith
- 👤 P Hartman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:12
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/494; G03C1/498; G03C1/49827
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
16 words
A photothermographic element as in claim 1 wherein said hydroxamic acid reducing agent has the formula:
Claim 2
Dependent Claim
16 words
A photothermographic element as in claim 1 wherein said hydroxamic acid reducing agent has the formula:
Claim 3
Dependent Claim
16 words
A photothermographic element as in claim 1 wherein said hydroxamic acid reducing agent has tHe formula:
Claim 4
Dependent Claim
16 words
A photothermographic element as in claim 1 wherein said hydroxamic acid reducing agent has the formula:
Claim 5
Dependent Claim
18 words
A photosensitive and thermosensitive element as in claim 1 wherein said hydroxamic acid reducing agent has the formula:
Claim 6
Dependent Claim
18 words
A photosensitive and thermosensitive element as in claim 1 wherein said hydroxamic acid reducing agent has the formula:
Claim 7
Dependent Claim
11 words
An element as in claim 1 further comprising an activator-toning agent.
Claim 8
Dependent Claim
11 words
An element as in claim 1 further comprising phthalazinone or phthalimide.
Claim 9
Dependent Claim
13 words
An element as in claim 1 further comprising a divalent salt image amplifier.
Claim 10
Dependent Claim
10 words
An element as in claim 1 further comprising zinc acetate.
Claim 11
Dependent Claim
11 words
An element as in claim 1 further comprising a stabilizer precursor.
Claim 12
Dependent Claim
43 words
A photothermographic element as in claim 1 comprising about 0.10 to about 4 moles of said reducing agent per mole of silver in said element and about 0.005 to about 0.50 mole of said photosensitive silver halide per mole of said oxidizing agent.
Claim 13
Dependent Claim
43 words
A photothermographic element as in claim 1 comprising, a. photosensitive silver halide, b. an oxidation-reduction image-forming combination comprising i. silver behenate with ii. a hydroxamic acid reducing agent, c. a polyvinyl butyral binder and d. an activator-toning agent which is phthalazinone or phthalimide.
Claim 14
Dependent Claim
37 words
A process of developing a latent image in an exposed photothermographic element comprising a photosensitive silver halide, and an oxidation-reduction image-forming combination comprising (i) an oxidizing agent with (ii) a hydroxamic acid reducing agent having the formula:
Claim 15
Dependent Claim
24 words
A process as in claim 15 comprising heating said element to about 80*C to about 250*C for about 0.5 second to about 10 seconds.
Claim 16
Dependent Claim
45 words
A process as in claim 15 of developing a latent image in an exposed photothermographic element comprising a support, a. photosensitive silver halide, b. an oxidation-reduction image-forming combination comprising: i. silver behenate and ii. a hydroxamic acid reducing agent comprising a compound of the formula:
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) | 1976-08-06 | 1977-02-05 | 1977-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-06 | 1981-02-05 | 1981-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-06 | 1985-02-05 | 1985-08-07 | $7700.00 | Window Closed / Lapsed |