US3647463A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct-positive photographic elements containing multiple layers
Assignee: Eastman Kodak Co
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Filing: 1969-08-14
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Granted: 1972-03-07
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Expires: 1989-08-14
Abstract
Abstract This invention relates to direct-positive silver halide elements comprising (1) duplicate layers containing silver halide emulsions having substantially the same light-response characteristics and (2) means for providing a sensitivity difference between said duplicate layers of at least 0.5 log exposure. In certain preferred embodiments, relatively lightinsensitive absorbing silver halide emulsions and/or lightabsorbing dyes are used in an interlayer to provide an effective density of 0.1 to 1.5.
Inventors
- 👤 Robert C Taber
- 👤 James E Koller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:54
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/76; G03C1/825; G03C1/005; G03C1/46; G03C1/485; G03C1/48515; Y; Y10; Y10S; Y10S430/00; Y10S430/141
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
18 words
A direct-positive photographic element according to claim 1 wherein said light-sensitive layers comprise fogged, direct-positive silver halide grains.
Claim 2
Dependent Claim
17 words
A direct-positive photographic element according to claim 1 wherein said light-sensitive layers comprise blue-sensitive-direct-positive silver halide emulsions.
Claim 3
Dependent Claim
23 words
A direct-positive element according to claim 1 wherein said light-sensitive layers each comprise fogged direct-positive silver halide emulsions of substantially the same sensitivity.
Claim 4
Dependent Claim
27 words
A direct-positive element according to claim 1 wherein at least one of said light-sensitive layers comprises an admixture of at least two portions of silver halide grains.
Claim 5
Dependent Claim
30 words
A direct-positive element according to claim 1 wherein at least one of said light-sensitive layers comprises silver halide grains having silver halide cores with a fogged silver halide cover thereon.
Claim 6
Dependent Claim
15 words
A direct-positive element according to claim 3 wherein said light-sensitive layers comprise a halogen conductor.
Claim 7
Dependent Claim
24 words
A direct-positive element according to claim 1 wherein said light-sensitive layers are at least ten times more sensitive to light than said light-insensitive interlayer.
Claim 8
Dependent Claim
16 words
A direct-positive element according to claim 3 wherein said light-sensitive layers comprise an organic electron acceptor.
Claim 9
Dependent Claim
23 words
A direct-positive element according to claim 1 wherein said light-sensitive layers comprise silver halide grains which are fogged by reduction and gold-fogging agents.
Claim 10
Dependent Claim
18 words
A direct-positive element according to claim 1 wherein one of said light-sensitive layers comprises a light-absorbing organic dye.
Claim 11
Dependent Claim
30 words
A direct-positive element according to claim 1 wherein the furthermost direct-positive, light-sensitive layer from the support is at least 50 percent thinner than at least one of said light-sensitive underlayers.
Claim 12
Dependent Claim
41 words
A direct-positive photographic element comprising (1) a support, (2) at least two layers comprising direct-positive, light-sensitive compositions of substantially the same light sensitivity and (3) means for providing a sensitivity difference in said light-sensitive layers of at least 0.5 log exposure.
Claim 13
Dependent Claim
24 words
A direct-positive photographic element according to claim 13 wherein said means is a light-insensitive 0.1 to 1.5 density layer interposed between said light-sensitive layers.
Claim 14
Dependent Claim
44 words
A direct-positive photographic element according to claim 13 wherein said means comprises light-absorbing dyes in one of said light-sensitive layers wherein said dyes have an effective absorption in the same region of the spectrum as the sensitivity of the light-sensitive compound of said layer.
Claim 15
Dependent Claim
23 words
A direct-positive photographic element according to claim 1 wherein said light-insensitive layer has an effective density of from about 0.3 to about 0.7.
References Cited (Backward Citations)
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US2566180A
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US3178282A
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US3450536A
Cited
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Cited
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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) | 1975-03-07 | 1975-09-06 | 1976-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-07 | 1979-09-06 | 1980-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-07 | 1983-09-06 | 1984-03-07 | $7700.00 | Window Closed / Lapsed |