US3978335A
Expired / Lapsed
US
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Electrographic recording process
Assignee: Eastman Kodak Co
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Filing: 1975-10-22
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Granted: 1976-08-31
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Expires: 1995-10-22
Abstract
Abstract A recording process is disclosed in which an X-ray sensitive photoconductive element exhibiting persistent conductivity and a charge sensitive, dry processable recording material are sandwiched between a pair of electrodes. A source of potential is applied across the electrodes and the photoconductive element is briefly exposed to an imagewise pattern of X-ray radiation forming a latent image in the recording material. Allowing the current to continue to flow through the sandwich after the X-ray exposure is terminated increases the sensitivity of the recording process by a factor of up to 100. The latent image is then amplified and rendered visible by uniformly heating the entire recording material.
Inventors
- 👤 Carl B. Gibbons
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:28
CPC Classifications
G; G03; G03G; G03G13/00; G03G13/054; G03C; G03C1/00; G03C1/494; G03C1/498; G03C1/49881; G03C5/00; G03C5/16; G03C5/56
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
108 words
An electrographic recording process comprising the steps of: a. positioning a persistent conductivity, X-ray sensitive photoconductive element adjacent a charge sensitive recording element containing a reducible metal compound in a binder; b. exposing the photoconductive element to an imagewise pattern of X-ray radiation while simultaneously applying an electrical potential across the photoconductive and recording elements said potential being of a magnitude sufficient to produce a latent image in the recording element; c. terminating the exposure of the photoconductive element and continuing the application of potential for a period of up to 300 seconds; and d. heating the entire recording element substantially uniformly to render the latent image visible.
Claim 2
Dependent Claim
108 words
An electrographic recording process comprising the steps of: a. positioning a persistent conductivity, X-ray sensitive photoconductive element adjacent a charge sensitive recording element containing a reducible metal compound in a binder; b. exposing the photoconductive element to an imagewise pattern of X-ray radiation while simultaneously applying an electrical potential across the photoconductive and recording elements said potential being of a magnitude sufficient to produce a latent image in the recording element; c. terminating the exposure of the photoconductive element and continuing the application of potential for a period of up to 300 seconds; and d. heating the entire recording element substantially uniformly to render the latent image visible.
Claim 3
Dependent Claim
19 words
The process of claim 1 wherein said photoconductive element comprises a lead oxide photoconductor coated on a conducting base.
Claim 4
Dependent Claim
23 words
The process of claim 1 wherein said recording element is heated to a temperature in the range of about 115°C to about 175°C.
Claim 5
Dependent Claim
25 words
The process of claim 1 wherein said recording element contains at least one metal salt of an organic fatty acid and a reducing agent therefor.
Claim 6
Dependent Claim
17 words
The process of claim 4 wherein the metal salt is a silver salt of an organic acid.
Claim 7
Dependent Claim
34 words
The process according to claim 5 wherein the silver salt is selected from the group consisting of silver behenate, silver stearate, silver oleate, silver hydroxystearate, silver laurate, silver palmitate, silver caprate and silver myristate.
Claim 8
Dependent Claim
126 words
An electrographic recording process comprising the steps of: a. positioning a persistent conductivity, X-ray sensitive photoconductive element adjacent a charge sensitive recording element containing a reducible metal compound in a binder; b. exposing the photoconductive element to an imagewise pattern of X-ray radiation while simultaneously applying an electrical potential of at least about 3 kilovolts across said photoconductive and recording elements, said potential being of a magnitude sufficient to produce a latent image in the areas of the recording element corresponding to the exposed areas of the photoconductive element; c. terminating the exposure of the photoconductive element and continuing the application of potential for a period of up to 300 seconds; and d. heating the entire recording element substantially uniformly to render the latent image visible.
Claim 9
Dependent Claim
126 words
An electrographic recording process comprising the steps of: a. positioning a persistent conductivity, X-ray sensitive photoconductive element adjacent a charge sensitive recording element containing a reducible metal compound in a binder; b. exposing the photoconductive element to an imagewise pattern of X-ray radiation while simultaneously applying an electrical potential of at least about 3 kilovolts across said photoconductive and recording elements, said potential being of a magnitude sufficient to produce a latent image in the areas of the recording element corresponding to the exposed areas of the photoconductive element; c. terminating the exposure of the photoconductive element and continuing the application of potential for a period of up to 300 seconds; and d. heating the entire recording element substantially uniformly to render the latent image visible.
Claim 10
Dependent Claim
139 words
An electrographic recording process comprising the steps of: a. positioning a persistent conductivity, X-ray sensitive photoconductive element adjacent a charge sensitive recording element containing a reducible metal compound in a binder; b. exposing the photoconductive element to an imagewise pattern of X-ray radiation while simultaneously applying an electrical potential across the photoconductive and recording elements, said potential being of a magnitude sufficient to produce a latent image in the areas of the recording element corresponding to the exposed areas of the photoconductive element; c. terminating the exposure of the photoconductive element and continuing the application of potential until a charge density of from approximately 1 microcouloumb/cm 2 to 1 millicouloumb/cm 2 is produced in the areas of the recording element containing said latent image; and d. heating the entire recording element substantially uniformly to render said latent image visible.
Claim 11
Dependent Claim
139 words
An electrographic recording process comprising the steps of: a. positioning a persistent conductivity, X-ray sensitive photoconductive element adjacent a charge sensitive recording element containing a reducible metal compound in a binder; b. exposing the photoconductive element to an imagewise pattern of X-ray radiation while simultaneously applying an electrical potential across the photoconductive and recording elements, said potential being of a magnitude sufficient to produce a latent image in the areas of the recording element corresponding to the exposed areas of the photoconductive element; c. terminating the exposure of the photoconductive element and continuing the application of potential until a charge density of from approximately 1 microcouloumb/cm 2 to 1 millicouloumb/cm 2 is produced in the areas of the recording element containing said latent image; and d. heating the entire recording element substantially uniformly to render said latent image visible.
Claim 12
Dependent Claim
144 words
An electrographic process comprising the steps of: a. positioning a persistent conductivity, X-ray sensitive photoconductive element adjacent a charge sensitive recording element containing a reducible metal compound in a binder; b. exposing the photoconductive element to an imagewise pattern of X-ray radiation while simultaneously applying an electrical potential of at least about 3 kilovolts across the photoconductive and recording elements, said potential being of a magnitude sufficient to produce a latent image in the areas of the recording element corresponding to the exposed areas of the photoconductive element; c. terminating the exposure of the photoconductive element and continuing the application of potential until a charge density of from approximately 1 microcouloumb/cm 2 to 1 millicouloumb/cm 2 is produced in the areas of the recording element containing said latent image; and d. heating the entire recording element substantially uniformly to render said latent image visible.
Claim 13
Dependent Claim
144 words
An electrographic process comprising the steps of: a. positioning a persistent conductivity, X-ray sensitive photoconductive element adjacent a charge sensitive recording element containing a reducible metal compound in a binder; b. exposing the photoconductive element to an imagewise pattern of X-ray radiation while simultaneously applying an electrical potential of at least about 3 kilovolts across the photoconductive and recording elements, said potential being of a magnitude sufficient to produce a latent image in the areas of the recording element corresponding to the exposed areas of the photoconductive element; c. terminating the exposure of the photoconductive element and continuing the application of potential until a charge density of from approximately 1 microcouloumb/cm 2 to 1 millicouloumb/cm 2 is produced in the areas of the recording element containing said latent image; and d. heating the entire recording element substantially uniformly to render said latent image visible.
References Cited (Backward Citations)
US3719824A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-31 | 1980-03-01 | 1980-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-31 | 1984-03-01 | 1984-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-31 | 1988-03-01 | 1988-08-31 | $7700.00 | Window Closed / Lapsed |