US4440851A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the formation of a direct positive image
Assignee: Konica Minolta Inc
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Filing: 1982-10-12
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Granted: 1984-04-03
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Expires: 2002-10-12
Abstract
Abstract A method for obtaining direct positive images wherein a photographic material having a support and at least two silver halide emulsion layers coated thereon, each layer having a different spectral sensitivity, said emulsions being of the internal latent image type and containing unfogged silver halide crystals, is imagewise exposed and then subjected to an overall area exposure prior to or during the development thereof to form the image. The overall area exposure is such that the photographic intensity ratios between various layers are not more than 6 and the intensity of such overall exposure has a value between light intensities which give 0.8 times the maximum image density of the particular emulsion layer and 10 times that light intensity value. The photographic intensity ratio is the ratio between photographic intensities of two emulsion layers and the photographic intensity is the reciprocal of the intensity value that corresponds to an image density which is 50% of the maximum when an imagewise-unexposed internal latent type image silver halide emulsion layer is subjected to light-intensity scale exposure and the density of the image formed is measured with a light which corresponds to the absorption maximum of the image.
Inventors
- 👤 Yasuo Tosaka
- 👤 Keiji Ogi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:05
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/3041; G03C1/00; G03C1/005; G03C1/485; G03C1/48538; G03C7/3022; Y; Y10; Y10S; Y10S430/00; Y10S430/141
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
205 words
A method for the formation of direct positive images wherein a silver halide light-sensitive color two silver halide emulsion layers having different spectral sensitivities coated thereon, said silver halide emulsion being an internal latent image type containing unfogged silver halide crystals, comprising imagewise exposing said photographic material and subsequently subjecting said material to an overall area exposure prior to or during the development thereof to form a direct positive image, wherein said overall area exposure is such that the photographic intensity ratios among said silver halide emulsion layers are not more than six, and the intensity of the overall area exposure has a value between a light intensity value yielding 0.8 times the maximum image density of an emulsion layer, and 10 times of said light intensity value, wherein said photographic intensity ratio is the ratio between photographic intensities of two emulsion layers and said photographic intensity is the reciprocal of the intensity value that corresponds to an image density which is 50% of the maximum when an imagewise-unexposed internal latent type silver halide emulsion layer is subjected to light-intensity scale exposure and the density of the image formed by said layer is measured with a light corresponding to the absorption maximum of the image.
Claim 2
Independent Claim
205 words
A method for the formation of direct positive images wherein a silver halide light-sensitive color two silver halide emulsion layers having different spectral sensitivities coated thereon, said silver halide emulsion being an internal latent image type containing unfogged silver halide crystals, comprising imagewise exposing said photographic material and subsequently subjecting said material to an overall area exposure prior to or during the development thereof to form a direct positive image, wherein said overall area exposure is such that the photographic intensity ratios among said silver halide emulsion layers are not more than six, and the intensity of the overall area exposure has a value between a light intensity value yielding 0.8 times the maximum image density of an emulsion layer, and 10 times of said light intensity value, wherein said photographic intensity ratio is the ratio between photographic intensities of two emulsion layers and said photographic intensity is the reciprocal of the intensity value that corresponds to an image density which is 50% of the maximum when an imagewise-unexposed internal latent type silver halide emulsion layer is subjected to light-intensity scale exposure and the density of the image formed by said layer is measured with a light corresponding to the absorption maximum of the image.
Claim 3
Dependent Claim
38 words
A method for the formation of a direct positive image according to claim 1 wherein said light intensity value of overall area exposure exists in the common interval of the light intensity intervals of silver halide emulsion layers.
Claim 4
Dependent Claim
36 words
A method for the formation of a direct positive image according to claim 1 wherein said photographic intensity ratios of said overall area exposure among said silver halide emulsion layers are respectively not more than four.
Claim 5
Dependent Claim
52 words
A method for the formation of a direct positive image according to claim 1 wherein the intensity of the overall area exposure has the value between the light intensity value interval which gives 0.8 times of the maximum image density of an emulsion layer and 6 times of said light intensity value.
Claim 6
Dependent Claim
50 words
A method for the formation of a direct positive image according to claim 1 wherein said silver halide color photographic material comprising an yellow image forming blue-sensitive silver halide emulsion layer, a magenta image forming green-sensitive silver halide emulsion layer, and a cyan image forming red-sensitive silver halide emulsion layer.
Claim 7
Dependent Claim
95 words
A method for the formation of a direct positive image according to claim 1 wherein said unfogged silver halide crystal is such that the density obtained by processing without exposing to light a test piece prepared by coating on a transparent support the emulsion containing said crystals so that the coating amount is 35 mg Ag/dm 2 in a surface developer having the following composition for 10 minutes at 20° C. does not exceed 0.6. ______________________________________
Metol 2.5 g
1-Ascorbic acid 10 g
NaBO--4HO 35 g
KBr 1 g
Water to make 1 liter
______________________________________
Claim 8
Dependent Claim
152 words
A method for the formation of a direct positive image according to claim 1 wherein said internal latent image type silver halide emulsion shows, when a test piece prepared by coating on a transparent support the emulsion so that the coated silver amount is 35 mg Ag/dm 2 is exposed to light in a light-intensity scale for a given period of up to 1 second and processed in said surface developer for 4 minutes at 20° C., such maximum density that is not greater than 1/5 of the maximum density obtained by subjecting another part of the test piece to exposure in the same manner and to the development with an internal developer having the following composition for 4 minutes at 20° C. ______________________________________
Metol 2 g
Sodium sulfite 90 g
(anhydrous)
Hydroquinon 8 g
Sodium carbonate 52.5 g
(monohydrate)
KBr 5 g
KI 0.5 g
Water to make 1 liter
______________________________________
Claim 9
Dependent Claim
151 words
A method for the formation of a direct positive image according to claim 5 wherein said internal latent image type silver halide emulsion shows, when a test piece prepared by coating on a transparent support the emulsion so that the coated silver amount is 35 mg Ag/dm 2 is exposed to light in a light-intensity scale for a given period of up to 1 second and processed in said surface developer for 4 minutes at 20° C., such maximum density that is not greater than 1/5 of the maximum density obtained by subjecting another part of th test piece to exposure in the same manner and to the development with an internal developer having following composition for 4 minutes at 20° C. ______________________________________
Methol 2 g
Sodium sulfite 90 g
(anhydrous)
Hydroquinon 8 g
Sodium carbonate 52.2 g
(monohydrate)
KBr 5 g
KI 0.5 g
Water to make 1 liter
______________________________________
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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) | 1987-04-03 | 1987-10-03 | 1988-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-04-03 | 1991-10-03 | 1992-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-04-03 | 1995-10-03 | 1996-04-03 | $7700.00 | Window Closed / Lapsed |