US3628956A - Process for preparing direct positive images by photosolubilization - Google Patents
Process for preparing direct positive images by photosolubilization Download PDFInfo
- Publication number
- US3628956A US3628956A US771347A US3628956DA US3628956A US 3628956 A US3628956 A US 3628956A US 771347 A US771347 A US 771347A US 3628956D A US3628956D A US 3628956DA US 3628956 A US3628956 A US 3628956A
- Authority
- US
- United States
- Prior art keywords
- silver halide
- silver
- organic compound
- process according
- percent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000004519 manufacturing process Methods 0.000 title description 4
- 229910052709 silver Inorganic materials 0.000 claims abstract description 80
- 239000004332 silver Substances 0.000 claims abstract description 80
- -1 silver halide Chemical class 0.000 claims abstract description 76
- 238000000034 method Methods 0.000 claims abstract description 24
- 239000002904 solvent Substances 0.000 claims abstract description 24
- CYCKHTAVNBPQDB-UHFFFAOYSA-N 4-phenyl-3H-thiazole-2-thione Chemical compound S1C(S)=NC(C=2C=CC=CC=2)=C1 CYCKHTAVNBPQDB-UHFFFAOYSA-N 0.000 claims abstract description 14
- 150000001875 compounds Chemical class 0.000 claims abstract description 8
- 150000002894 organic compounds Chemical class 0.000 claims description 25
- 238000004090 dissolution Methods 0.000 claims description 19
- 239000000839 emulsion Substances 0.000 claims description 19
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 claims description 14
- 235000019345 sodium thiosulphate Nutrition 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 239000006185 dispersion Substances 0.000 claims description 12
- 239000003638 chemical reducing agent Substances 0.000 claims description 11
- 229910021607 Silver chloride Inorganic materials 0.000 claims description 10
- SJOOOZPMQAWAOP-UHFFFAOYSA-N [Ag].BrCl Chemical compound [Ag].BrCl SJOOOZPMQAWAOP-UHFFFAOYSA-N 0.000 claims description 10
- 229920000159 gelatin Polymers 0.000 claims description 10
- 235000019322 gelatine Nutrition 0.000 claims description 10
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 claims description 10
- 108010010803 Gelatin Proteins 0.000 claims description 8
- 239000007864 aqueous solution Substances 0.000 claims description 8
- 239000008273 gelatin Substances 0.000 claims description 8
- 235000011852 gelatine desserts Nutrition 0.000 claims description 8
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 7
- 230000005855 radiation Effects 0.000 claims description 7
- 239000005708 Sodium hypochlorite Substances 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 6
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 claims description 6
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 claims description 5
- 229910052740 iodine Inorganic materials 0.000 claims description 5
- 239000011630 iodine Substances 0.000 claims description 5
- 230000001590 oxidative effect Effects 0.000 claims description 5
- GGCZERPQGJTIQP-UHFFFAOYSA-N sodium;9,10-dioxoanthracene-2-sulfonic acid Chemical compound [Na+].C1=CC=C2C(=O)C3=CC(S(=O)(=O)O)=CC=C3C(=O)C2=C1 GGCZERPQGJTIQP-UHFFFAOYSA-N 0.000 claims description 5
- 238000005063 solubilization Methods 0.000 claims description 5
- 230000007928 solubilization Effects 0.000 claims description 5
- 238000013019 agitation Methods 0.000 claims description 3
- 239000004215 Carbon black (E152) Substances 0.000 claims description 2
- 239000001828 Gelatine Substances 0.000 claims description 2
- 125000004432 carbon atom Chemical group C* 0.000 claims description 2
- 229930195733 hydrocarbon Natural products 0.000 claims description 2
- 150000002430 hydrocarbons Chemical class 0.000 claims description 2
- KXZSVYHFYHTNBI-UHFFFAOYSA-N 1h-quinoline-2-thione Chemical compound C1=CC=CC2=NC(S)=CC=C21 KXZSVYHFYHTNBI-UHFFFAOYSA-N 0.000 claims 1
- 239000010410 layer Substances 0.000 description 27
- 239000000243 solution Substances 0.000 description 18
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 239000003795 chemical substances by application Substances 0.000 description 6
- LLEMOWNGBBNAJR-UHFFFAOYSA-N biphenyl-2-ol Chemical compound OC1=CC=CC=C1C1=CC=CC=C1 LLEMOWNGBBNAJR-UHFFFAOYSA-N 0.000 description 4
- 239000013078 crystal Substances 0.000 description 4
- 239000012153 distilled water Substances 0.000 description 3
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical class S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 2
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 2
- 229910052783 alkali metal Inorganic materials 0.000 description 2
- 239000000084 colloidal system Substances 0.000 description 2
- 150000004820 halides Chemical class 0.000 description 2
- 235000010292 orthophenyl phenol Nutrition 0.000 description 2
- 229920000139 polyethylene terephthalate Polymers 0.000 description 2
- 239000005020 polyethylene terephthalate Substances 0.000 description 2
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical compound [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- POAOYUHQDCAZBD-UHFFFAOYSA-N 2-butoxyethanol Chemical compound CCCCOCCO POAOYUHQDCAZBD-UHFFFAOYSA-N 0.000 description 1
- ZZEYCGJAYIHIAZ-UHFFFAOYSA-N 4-methyl-1-phenylpyrazolidin-3-one Chemical compound N1C(=O)C(C)CN1C1=CC=CC=C1 ZZEYCGJAYIHIAZ-UHFFFAOYSA-N 0.000 description 1
- ZFIQGRISGKSVAG-UHFFFAOYSA-N 4-methylaminophenol Chemical compound CNC1=CC=C(O)C=C1 ZFIQGRISGKSVAG-UHFFFAOYSA-N 0.000 description 1
- PIVQQUNOTICCSA-UHFFFAOYSA-N ANTU Chemical compound C1=CC=C2C(NC(=S)N)=CC=CC2=C1 PIVQQUNOTICCSA-UHFFFAOYSA-N 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- LSDPWZHWYPCBBB-UHFFFAOYSA-N Methanethiol Chemical compound SC LSDPWZHWYPCBBB-UHFFFAOYSA-N 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 239000002671 adjuvant Substances 0.000 description 1
- 230000001476 alcoholic effect Effects 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- CODNYICXDISAEA-UHFFFAOYSA-N bromine monochloride Chemical compound BrCl CODNYICXDISAEA-UHFFFAOYSA-N 0.000 description 1
- FGRVOLIFQGXPCT-UHFFFAOYSA-L dipotassium;dioxido-oxo-sulfanylidene-$l^{6}-sulfane Chemical compound [K+].[K+].[O-]S([O-])(=O)=S FGRVOLIFQGXPCT-UHFFFAOYSA-L 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 229940060367 inert ingredients Drugs 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 229920000126 latex Polymers 0.000 description 1
- 239000006224 matting agent Substances 0.000 description 1
- DZVCFNFOPIZQKX-LTHRDKTGSA-M merocyanine Chemical compound [Na+].O=C1N(CCCC)C(=O)N(CCCC)C(=O)C1=C\C=C\C=C/1N(CCCS([O-])(=O)=O)C2=CC=CC=C2O\1 DZVCFNFOPIZQKX-LTHRDKTGSA-M 0.000 description 1
- 229920000620 organic polymer Polymers 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- DHCDFWKWKRSZHF-UHFFFAOYSA-N sulfurothioic S-acid Chemical compound OS(O)(=O)=S DHCDFWKWKRSZHF-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
- G03C1/00—Photosensitive materials
- G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
- G03C1/492—Photosoluble emulsions
Definitions
- Goodrow Attorney-Lynn Barratt Morris ABSTRACT Process for forming a positive silver halide image by treating an imagewise-expo'sed, light-sensitive silver halide layer with a photosolubilizing compound, e.g., Z-mercapto-4-phenylthiazole, and then removing the exposed silver halide with a silver halide solvent.
- a photosolubilizing compound e.g., Z-mercapto-4-phenylthiazole
- the invention concerns a process for forming a positive silver halide image by treating an imagewise exposed light-sensitive silver halide layer with a photosolubilizing compound and then removing the exposed silver halide by dissolution development (i.e., treating with a silver halide solvent solution).
- the invention is an improvement over the prior art in the sense that it enables one to obtain a positive image by reduction dissolution techniques in normal silver halide layers.
- an auxiliary organic compound devoid of ionizsble iodine or oxidizing groups which are active at the working pH, which further reduces the rate of dissolution of unexposed silver halide in a silver halide solvent, thereby effecting the solubilization of the silver halide in the more exposed areas at a rate substantially greater than in the less exposed areas until a positive image comprised of silver halide is produced.
- the silver halide solvent is an aqueous solution of an alkali metal thiosulfate, e.g., sodium or potassium thiosulfate.
- an alkali metal thiosulfate e.g., sodium or potassium thiosulfate.
- Suitable auxiliary compounds or D maintaining agents that can be used in accordance with the present invention include those defined and classified in aforesaid U.S. Pat. Nos. 3,493,373, 3,495,982 and 3,495,983.
- a colloid-silver halide photographic emulsion layer coated on a suitable support, is exposed imagewise to actinic radiation.
- the exposed element is then treated with a solution containing an organic compound as described above, e.g., 2-mercapto-4-phenylthiazole, the silver salt of which is of lower solubility in water than silver chloride, so as to reduce the rate of dissolution of unexposed silver halide solvent, e.g., a solution of sodium thiosulfate.
- a positive modified silver halide image is formed in the silver halide emulsion layer.
- the modified silver halide image may be intensified in various ways, as described in U.S. Pat. No. 3,155,507.
- the most useful means of intensification involves reducing the white to yellow silver halide image to a black, metallic silver image, preferably using a photographic silver halide developing agent.
- the silver halide image may be fogged prior to reduction by flashing to actinic radiation.
- Other methods of intensifying the silver halide image e.g., by toning, color developing, etc., are disclosed in U.S. Pat. No. 3,155,507.
- step (b) in treating the exposed photographic element are mercaptans
- various other organic compounds may be used such as those disclosed in the above U.S. patents and applications for the manufacture of photosoluble elements.
- the organic compounds disclosed in U.S. Pat. No. 3,155,519 are especially useful, e.g., 2-mercapto-4-phenylthiazole (MPT).
- the silver halide solvent solution used in step (c) is an aqueous solution comprising two or three essential compounds: a silver halide solvent and a reducing agent, and, if desired, a D, maintaining agent.
- Thesilver halide solvent may be any soluble thiosulfate, e.g., ammonium or alkali metal thiosulfate, but sodium thiosulfate is the preferred solvent.
- Suitable reducing agents and their useful concentrations are those disclosed in assignee's copending application, U.S. Ser. No. 684,924, filed Nov. 22, 1967.
- Reducing agents of the class recognized as conventional photographic developing agents for silver halide emulsions are preferred although other reducing agents are useful, including preferably N-methyl-p-aminophenol, 1- phenyl-4-methyl-3-pyrazolidone and l-phenyl-3- pyrazolidone.
- Particularly useful D, maintaining compounds are o-phenylphenol, 2-butoxyethanol, and 1-(1- naphthyl )-2 -thiourea.
- the silver halide layers or elements used in accordance with this invention may be silver chloride, silver bromide, silver chlorobromide, etc., and may contain gelatin or other macromolecular organic water-permeable colloid binding "was: rnm
- the elements may be modified by variations in the silver halide, the binder (if present), and the adjuvants generally employed in silver halide systems, the supports, and in the relative concentrations of the various components in the layers.
- Various auxiliary layers such as abrasion overcoatings, subbing layers, and antihalation undercoats or backing layers may be present in the photographic elements used in accordance with this invention.
- the elements may include multilayer as well as monolayer structures.
- the various layers, including the support may include inert ingredients, e.g., pigments, organic polymer latices, and matting agents.
- EXAMPLE i A film strip of a gelatino-silver bromochloride emulsion (30% AgBr, 70% AgCl) on a polyethylene terephthalate support was exposed through a photographic 5 step wedge to a high-intensity, tungsten filament, incandescent lamp (General Electric Reflector Photoflood Lamp No. PHIRFLZ) at a distance of 2 feet for 5 minutes.
- MPT 2-mercapto-4- phenylthiazole
- a direct positive silver halide image resulted which was intensified by developing for 1 minute in the following photographic developer solution to yield an image having as maximum density (D,,,,,,) of 3.2 and a minimum density (D,,,,,.,) of 1.0:
- EXAMPLE lll A strip of the exposed film described in example I (except that exposure was for 20 minutes) was soaked in hot water (about i130 F.) for 3 minutes, soaked in a 0.] percent by wt. aqueous solution of l-naphthyHZ-thiourea for l minute, washed for 2 minutes, treated for 1 minute in the dissolution developer of example I and intensified as in example I.
- EXAMPLEV A pure silver chloride emulsion having an average grain diameter of about 0.5 micron was chemically sensitized with gold and sulfur sensitizers, and spectrally sensitized with a merocyanine dye.
- a film strip of this emulsion coated on a polyethylene terephthalate support was exposed through a photographic 2 wedge for 1 sec. at a distance of 76 cm. to a SOD-watt tungsten filament incandescent lamp operated at a color temperature of 2,890 K., and fitted with a Wratten No. 79 filter.
- the exposed strip was soaked for 15 sec. in a solution prepared by dissolving 0.l6l g. of Z-rnercaptoquinoline in 50 ml.
- EXAMPLE VI A sample of the emulsion of example V was coated, exposed and processed as in example V, except that the strip was soaked in the Z-mercaptoquinoline solution for 30 sec. and had a D of3.70 and a D,,,,,, of 0.4l.
- EXAMPLE Vll A strip of the coated emulsion of example V was exposed as in example V, except that the exposure was for 2 sec. The exposed strip was soaked for l minute in a solution made by dissolving 0.l93 g. of 2-mercapto-4-phenylthiazole in 50 ml. of ethanol, adding 350 ml. of distilled water and adjusting the pH to 9. This solution was kept at ll5 F. The soaked strip was then treated as in example V, except that the treatment with the reducing dissolution developer was for 6 minutes. The strip had a D of 2.99 and a D of 0.25.
- EXAMPLE Vlll A sample of the coated emulsion of example V was exposed as in example Vll. The exposed sample was processed as in example Vll, except that the dissolution developer contained no o-phenylphenol. After intensification as in example l, D was 3.36 and D,,,,,, 0.80.
- EXAMPLE 1X A strip of the coated emulsion of example V was exposed as in example V. The exposed strip was soaked in a solution containing 0.34 g. of l,2-naphthatriazole per I00 ml. of distilled water with pH adjusted to 9, for l minute at F. The treated strip was then developed for l minute at 70 F. in the reducing dissolution developer of example i, washed for 30 sec, and intensified in the photographic developer of example I for 1 minute at 70 F. A direct positive image was obtained having a D of0.89 and a D of0.20.
- the present invention has the advantages of the basic process of photosolubilization of Blake U.S. Pat. No. 3 ,l 55 ,507 and embodies simple processing to obtain a positive image.
- Conventional emulsions may be used by this process to yield the same results as obtained with specially prepared photosoluble emulsion layers described in said patent.
- said silver halide solvent of step (c) also contains a D maintaining amount of an auxiliary organic compound devoid of ionizable iodine or oxidizing groups which are active at the working pH, which further reduces the rate of dissolution of unexposed silver halide in a silver halide solvent, thereby effecting the solubilization of the silver halide in the more exposed areas at a rate substantially greater than in the less exposed areas until a positive image comprised of silver halide is produced.
- R is a hydrocarbon nucleus of 4-l 2 carbon atoms.
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Photosensitive Polymer And Photoresist Processing (AREA)
- Silver Salt Photography Or Processing Solution Therefor (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US68899667A | 1967-12-08 | 1967-12-08 | |
| US77134768A | 1968-10-28 | 1968-10-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3628956A true US3628956A (en) | 1971-12-21 |
Family
ID=27104326
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US771347A Expired - Lifetime US3628956A (en) | 1967-12-08 | 1968-10-28 | Process for preparing direct positive images by photosolubilization |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | US3628956A (esLanguage) |
| BE (1) | BE725071A (esLanguage) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3155507A (en) * | 1961-12-08 | 1964-11-03 | Du Pont | Photographic processes |
| US3495982A (en) * | 1967-06-23 | 1970-02-17 | Du Pont | Process for dissolution development using thiourea compounds as dmax maintainers |
-
1968
- 1968-10-28 US US771347A patent/US3628956A/en not_active Expired - Lifetime
- 1968-12-06 BE BE725071D patent/BE725071A/xx unknown
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3155507A (en) * | 1961-12-08 | 1964-11-03 | Du Pont | Photographic processes |
| US3155519A (en) * | 1961-12-08 | 1964-11-03 | Du Pont | Photographic compositions, layers and elements |
| US3495982A (en) * | 1967-06-23 | 1970-02-17 | Du Pont | Process for dissolution development using thiourea compounds as dmax maintainers |
Also Published As
| Publication number | Publication date |
|---|---|
| BE725071A (esLanguage) | 1969-06-06 |
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