US3856526A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Protective layer for photothermographic elements
Assignee: Eastman Kodak Co
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Filing: 1973-08-06
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Granted: 1974-12-24
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Expires: 1993-08-06
Abstract
Abstract On a photographic element comprising at least one heatprocessable, photographic layer, a protective layer comprising certain carboxylic polyesters provides improved resistance to abrasion and fingerprinting, resistance to reticulation and surface cracking without adversely affecting sensitomeric properties of the photographic element upon processing. A latent image in such an element can be developed by uniformly heating the element containing the protective layer. Silica particles in the protective layer can enhance resistance of the protective layer to sticking to a heated metal surface and further enable the layer to glide smoothly over the heated metal surface.
Inventors
- 👤 F Hamb
- 👤 G Hiller
- 👤 A Wise
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:39
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/494; G03C1/498; G03C1/49872; G03C1/76; G03C1/7614; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31786; Y10T428/3179
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
31 words
IN A PHOTOTHERMOGRAPHIC ELEMENT HAVING A PROTECTIVE LAYER, THE IMPROVEMENT COMPRISING AS SAID PROTCETIVE LAYER A CARBOXYLIC POLYSTER HAVING A GLASS TRANSITION TEMPERATURE OF AT LEAST 190*C REPRESENTED ;BY THE FORMULA:
Claim 2
Dependent Claim
31 words
IN A PHOTOTHERMOGRAPHIC ELEMENT HAVING A PROTECTIVE LAYER, THE IMPROVEMENT COMPRISING AS SAID PROTCETIVE LAYER A CARBOXYLIC POLYSTER HAVING A GLASS TRANSITION TEMPERATURE OF AT LEAST 190*C REPRESENTED ;BY THE FORMULA:
Claim 3
Dependent Claim
33 words
In a photothermographic element having a protective overcoat layer, the improvement comprising as said protective, overcoat layer a carboxylic polyester having a glass transition temperature of at least 200*C. represented by the formula:
Claim 4
Dependent Claim
33 words
In a photothermographic element having a protective overcoat layer, the improvement comprising as said protective, overcoat layer a carboxylic polyester having a glass transition temperature of at least 200*C. represented by the formula:
Claim 5
Dependent Claim
24 words
A photothermographic element as in claim 1 wherein said carboxylic polyester is a copolymer of (i) terephthalic acid, (ii) 3,3,3'',3''-tetramethyl-1,1''-spirobi(indan)-6,6''-diol and (iii) bisphenol A.
Claim 6
Dependent Claim
29 words
A photothermographic element as in claim 1 wherein said protective layer comprises about 50 mg. to about 300 mg. of said carboxylic polyester per 929 square centimeters of suPport.
Claim 7
Dependent Claim
51 words
A photothermographic element having thereon a protective layer as in claim 1 wherein said photothermographic element comprises a support and I. an oxidation-reduction image-forming combination comprising i. a silver salt oxidizing agent with ii. an organic reducing agent, II. photosensitive silver halide, III. a polymeric binder, and IV. an activator-toning agent.
Claim 8
Dependent Claim
82 words
In a photothermographic element having thereon a protective layer wherein said photothermographic element comprises a support and a. an oxidation-reduction image-forming combination comprising i. silver behenate with ii. a sulfonamidophenol reducing agent, b. photosensitive silver halide, c. a poly(vinyl butyral) binder, and d. an activator-toning agent comprising N-hydroxynaphthalimide, and a protective layer the improvement wherein said protective layer is a copolymer of (i) terephthalic acid, (ii) 3,3,3'',3''-tetramethyl-1,1''-spirobi(indan)-6,6''-diol, and (iii) bisphenol A, said copolymer having a glass transition temperature of at least 190*C.
Claim 9
Dependent Claim
82 words
In a photothermographic element having thereon a protective layer wherein said photothermographic element comprises a support and a. an oxidation-reduction image-forming combination comprising i. silver behenate with ii. a sulfonamidophenol reducing agent, b. photosensitive silver halide, c. a poly(vinyl butyral) binder, and d. an activator-toning agent comprising N-hydroxynaphthalimide, and a protective layer the improvement wherein said protective layer is a copolymer of (i) terephthalic acid, (ii) 3,3,3'',3''-tetramethyl-1,1''-spirobi(indan)-6,6''-diol, and (iii) bisphenol A, said copolymer having a glass transition temperature of at least 190*C.
Claim 10
Dependent Claim
35 words
A process of developing an image in a photothermographic element having thereon a protective overcoat layer comprising a carboxylic polyester as defined in claim 1 comprising heating said element from about 80*C. to about 250*C.
Claim 11
Dependent Claim
19 words
A process as in claim 7 wherein said heating is carried out for about 0.5 to about 60 seconds.
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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) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |