US2879160A - Composition for developing surface disturbances on a photographic film - Google Patents
Composition for developing surface disturbances on a photographic film Download PDFInfo
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- US2879160A US2879160A US455073A US45507354A US2879160A US 2879160 A US2879160 A US 2879160A US 455073 A US455073 A US 455073A US 45507354 A US45507354 A US 45507354A US 2879160 A US2879160 A US 2879160A
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- film
- photographic
- developer
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- composition
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- 239000000203 mixture Substances 0.000 title description 3
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 claims description 22
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 12
- CYXJEHCKVOQFOV-UHFFFAOYSA-N (4-amino-2-methylphenyl) hydrogen sulfate Chemical compound CC1=CC(N)=CC=C1OS(O)(=O)=O CYXJEHCKVOQFOV-UHFFFAOYSA-N 0.000 claims description 5
- 238000011161 development Methods 0.000 description 11
- 230000018109 developmental process Effects 0.000 description 10
- -1 hydrazine compound Chemical class 0.000 description 10
- OAKJQQAXSVQMHS-UHFFFAOYSA-N hydrazine Substances NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 description 9
- 150000001875 compounds Chemical class 0.000 description 8
- ZVNPWFOVUDMGRP-UHFFFAOYSA-N 4-methylaminophenol sulfate Chemical compound OS(O)(=O)=O.CNC1=CC=C(O)C=C1.CNC1=CC=C(O)C=C1 ZVNPWFOVUDMGRP-UHFFFAOYSA-N 0.000 description 7
- 239000003513 alkali Substances 0.000 description 7
- FERIUCNNQQJTOY-UHFFFAOYSA-N Butyric acid Chemical compound CCCC(O)=O FERIUCNNQQJTOY-UHFFFAOYSA-N 0.000 description 6
- 239000000839 emulsion Substances 0.000 description 5
- UCRQERNMLOPFFS-UHFFFAOYSA-N (4-pentan-2-ylphenyl)hydrazine Chemical compound CCCC(C)C1=CC=C(NN)C=C1 UCRQERNMLOPFFS-UHFFFAOYSA-N 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 229960000443 hydrochloric acid Drugs 0.000 description 4
- 235000011167 hydrochloric acid Nutrition 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- ALSJNZXLSRPIDZ-UHFFFAOYSA-N 1-tert-butyl-1-phenylhydrazine Chemical class CC(C)(C)N(N)C1=CC=CC=C1 ALSJNZXLSRPIDZ-UHFFFAOYSA-N 0.000 description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 238000007792 addition Methods 0.000 description 2
- 150000002429 hydrazines Chemical class 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- FBUKVWPVBMHYJY-UHFFFAOYSA-N nonanoic acid Chemical compound CCCCCCCCC(O)=O FBUKVWPVBMHYJY-UHFFFAOYSA-N 0.000 description 2
- 230000002441 reversible effect Effects 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- LPXPTNMVRIOKMN-UHFFFAOYSA-M sodium nitrite Chemical compound [Na+].[O-]N=O LPXPTNMVRIOKMN-UHFFFAOYSA-M 0.000 description 2
- FWPIDFUJEMBDLS-UHFFFAOYSA-L tin(II) chloride dihydrate Chemical compound O.O.Cl[Sn]Cl FWPIDFUJEMBDLS-UHFFFAOYSA-L 0.000 description 2
- TXUICONDJPYNPY-UHFFFAOYSA-N (1,10,13-trimethyl-3-oxo-4,5,6,7,8,9,11,12,14,15,16,17-dodecahydrocyclopenta[a]phenanthren-17-yl) heptanoate Chemical compound C1CC2CC(=O)C=C(C)C2(C)C2C1C1CCC(OC(=O)CCCCCC)C1(C)CC2 TXUICONDJPYNPY-UHFFFAOYSA-N 0.000 description 1
- VSTZVCJQGSLNLL-UHFFFAOYSA-N 2-aminophenyl hydrogen sulfate Chemical compound NC1=CC=CC=C1OS(O)(=O)=O VSTZVCJQGSLNLL-UHFFFAOYSA-N 0.000 description 1
- QCQCHGYLTSGIGX-GHXANHINSA-N 4-[[(3ar,5ar,5br,7ar,9s,11ar,11br,13as)-5a,5b,8,8,11a-pentamethyl-3a-[(5-methylpyridine-3-carbonyl)amino]-2-oxo-1-propan-2-yl-4,5,6,7,7a,9,10,11,11b,12,13,13a-dodecahydro-3h-cyclopenta[a]chrysen-9-yl]oxy]-2,2-dimethyl-4-oxobutanoic acid Chemical class N([C@@]12CC[C@@]3(C)[C@]4(C)CC[C@H]5C(C)(C)[C@@H](OC(=O)CC(C)(C)C(O)=O)CC[C@]5(C)[C@H]4CC[C@@H]3C1=C(C(C2)=O)C(C)C)C(=O)C1=CN=CC(C)=C1 QCQCHGYLTSGIGX-GHXANHINSA-N 0.000 description 1
- AKSSDFIINGVZJQ-UHFFFAOYSA-N 4-pentan-2-ylaniline Chemical compound CCCC(C)C1=CC=C(N)C=C1 AKSSDFIINGVZJQ-UHFFFAOYSA-N 0.000 description 1
- 241000167854 Bourreria succulenta Species 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 239000005643 Pelargonic acid Substances 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 229910021626 Tin(II) chloride Inorganic materials 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 235000019693 cherries Nutrition 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000012954 diazonium Substances 0.000 description 1
- 150000001989 diazonium salts Chemical class 0.000 description 1
- 238000006193 diazotization reaction Methods 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 235000019441 ethanol Nutrition 0.000 description 1
- 239000012458 free base Substances 0.000 description 1
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 description 1
- LIAWOTKNAVAKCX-UHFFFAOYSA-N hydrazine;dihydrochloride Chemical compound Cl.Cl.NN LIAWOTKNAVAKCX-UHFFFAOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 229940067157 phenylhydrazine Drugs 0.000 description 1
- HKOOXMFOFWEVGF-UHFFFAOYSA-N phenylhydrazine Chemical compound NNC1=CC=CC=C1 HKOOXMFOFWEVGF-UHFFFAOYSA-N 0.000 description 1
- 230000003389 potentiating effect Effects 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
- 239000012056 semi-solid material Substances 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 235000010288 sodium nitrite Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000001119 stannous chloride Substances 0.000 description 1
- 235000011150 stannous chloride Nutrition 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000008399 tap water Substances 0.000 description 1
- 235000020679 tap water Nutrition 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
- G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
- G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
- G03C5/29—Development processes or agents therefor
- G03C5/305—Additives other than developers
Definitions
- This invention relates to amethod of developing surface disturbances on unexposedphotographic film. More particularly it relates to a method of producing fingerprints on unexposed photographic film and to a novel chemical compound which, when added to certain photographic developers, produces this result.
- the particular hydrazine compound which produces the results above outlined is p-sec-amylphenylhydrazine (otherwise designated as p-(1-methylbuty1)phenylhydrazine).
- the hydrochloride ofthis compound is added to the high alkali metol hydroquinone developer in the very small concentration of 1" .l0- moles per liter, which amounts to only 2.1 mgs. per liter of developer.
- the fingerprint or other surface disturbance is accomplished on the emulsion surface of the film in total darkness and the film is developed without exposure to light.
- Reduction is. accomplished at below zero degrees C. by adding '90 g. of stannous chloride dihydrate in 94 ml. of concentrated hydrochloric acid.
- the original light tan slurry gradually assumes the consistency of thick dough.
- a high alkali photographic developer containing monomethyl-para-aminophenol-sulfate, hydroquinone and a minute quantity of p-sec-amylphenylhydrazine hydrochloride.
- a high alkali photographic developer containing monomethyl para aminophenol-sulfate, hydroquinone and p-sec-amylphenylhydrazine hydrochloride in a concentration of about 2 mg. per liter.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
COMPOSITION FOR DEVELOPING SURFACE DIS- .TURBANCES ON A PHOTOGRAPHIC FILM Isaac Moyer Hunsherger, Yellow Springs, Ohio, assignor to Antioch College of Yellow Springs, Greene County, Ohio, a corporation of Ohio No Drawing. Application September 9, 1954 Serial No. 455,073
4 Claims. (CI. 96-66) This invention relates to amethod of developing surface disturbances on unexposedphotographic film. More particularly it relates to a method of producing fingerprints on unexposed photographic film and to a novel chemical compound which, when added to certain photographic developers, produces this result.
A great amount of work has been done ,in recentyears in connection with photographic developers in an effort to find substances which, when added to the photographic developer, enhance the effective film speed so that acceptable negatives may be obtained from underexposed .film. Thus, it is known to add hydrazine dihydrochloride to a high alkali metol hydroquinone developer for the purpose of increasing the effective film speed. (Metol is a trade name for methyl-para-aminophenol sulfate.)
In connection with research along these lines, I have discovered that a particular hydrazine compound produces certain novel and completely unexpected results, in thatsurface disturbances on the emulsion surface, produced by pressure or the like, are developed on the film and that these results are obtained with additions of minute quantities of the particular compound in question to the appropriate photographic developer.
It is therefore an object of the present invention to provide as an article of manufacture a compound which may be added to a photographic developer for developing rates Patent sults have been obtained with Eastman FD-81 D-42 Water to make 1 liter.
(Elon is a trade name for methyl-para-aminophenol sulfate.)
The particular hydrazine compound which produces the results above outlined is p-sec-amylphenylhydrazine (otherwise designated as p-(1-methylbuty1)phenylhydrazine). The hydrochloride ofthis compound is added to the high alkali metol hydroquinone developer in the very small concentration of 1" .l0- moles per liter, which amounts to only 2.1 mgs. per liter of developer. When the D-19 developerisnsed without the hydrazine compound, no fingerprintis developedbut With the small concentration of the hydrazine compound added, clear and legible fingerprints are obtained.
The fingerprint or other surface disturbance is accomplished on the emulsion surface of the film in total darkness and the film is developed without exposure to light.
surface disturbances on an unexposed photographic film. t
Excellent results have been obtained by development for eight minutes in a tank with mechanical agitation using D-l9 developer containing 2.1 mgs. per liter of p-secamylphenylhydrazine hydrochloride. 'The development time depends upon the 'type of film and the developer used. The film must'be fogged by development, and'optimum fog appears to 'be between 0.70 and 1.6.
I have noted that fingerprints develop more legibly if the hands .have not been'freshly washedand dried. Similarly, a rubber stamp impression on a photographic emulsion will develop more legibly and clearly, if the rubber stamp has been surface coated with any of such substances as pure butyric acid, butyric acid in dilute aqueous solutions, distilled water, tap water, pelargonic acid, hydrochloric acid, ethyl alcohol, etc. Since butyric acid is present in perspiration, this may be why clean dry fingers do not produce as good a print as fingers which are not freshly washed and dry.
I have made similar tests using rubber stamps coated V with a film of the various compounds mentioned above speed panchromaticfilm and press .the finger against the emulsion side of the film in total darkness. I then develop the film in a metol hydroquinone developer .to which I have added a minute quantity of the hydrazine compound, which will be described hereinafter. Upon development very legible fingerprints are obtained and contact prints made from such negatives show fingerprints of high quality.
With the particular compound to be described herein after, successful results can be obtained with any of the high speed panchromatic photographic films. In my experience I have been able to develop fingerprints on films known commercially as Ansco Triple S Pan Sheet Film," Eastman Kodak Aerographic Tri-X, Super-XX, Plus- X and Verichrome films; however the best results have been obtained with Ansco Triple S Pan Sheet Film and Eastman Kodak Aerographic Tri-X. Similarly, I have obtained best results with a high alkali metol hydroquinone developer manufactured by Eastman Kodak, Inc. under the name of D-19, although reasonably good rewith development in D49 containing no p-sec-amylphenylhydrazine. I found that if the developing temperature was raised from 68 F. to 80 F. and if the -development time was increased 'fromabout 8 minutes to about 20 minutes so as to attain the desired high fog level, clear images of the stamp were obtained on development. Interestingly, however, the stamped area on the negative was darker, i. c. more silver grains, so that in the contact prints the stamped areas were lighter than the surrounding area. When p-sec-amylphenylhydrazine was added to the developer, exactly the reverse effect was produced. In other Words, the stamped area of the negative was lighter and on the contact print the stamped area was darker.
While I do not wish to be bound by my theory, I believe that one of the functions of the coating, either on the rubber stamp or on the finger, is to retard in some way the development rate of that area of the film which I was disturbed by the stamp. The reversal effect with dred hydrazine compounds which I have tested over a three-year period, p-sec-amylphenylhydrazine is the only one which produces legible fingerprints although some of the other compounds do, to some extent, produce develop ment of abrasions and scratches to varying degrees. The structurallyvery closely related t-butylphenylhydrazines atjfaconcentration of 1 10- M in D-l9 displayed some activity in developing impressions made by rubber stamps coated with a variety of the substances mentioned above. However, the t-butylphenylhydrazines showed no'activity'whatever in developing fingerprints on negatives even "though theorthoInieta, andypara isomers were tested. at concentrations of l 10- and 1X 10 M in .*D-19.-'- 1 a T he particularhydrazine derivative here involved has beenv unreported in the literature up to the present time. Itmay be preparedby diazotization of p-sec-amylaniline followed byreduction of the diazonium salt with stannous chloride and hydrochloricacid' Thus, 22.5 g. offreshly distilled (from zinc dust) p'- sec-'amylanilineis' mixed with 51 ml. of concentrated hydrochloric acid and diazotized at below zero degrees C.
with 9.5 g. of sodium nitrite 45 ml. of water. On stirring the-mixture for an additional half hour, its surface becomes dark red.
Reduction is. accomplished at below zero degrees C. by adding '90 g. of stannous chloride dihydrate in 94 ml. of concentrated hydrochloric acid. The original light tan slurry gradually assumes the consistency of thick dough.
After overnight refrigeration, the slurry is filtered as completely as possible and the collected semi-solid material is-treated with an excess of sodium hydroxide, The now bright yellow product is extracted into ether and the dried and cooled extract is treated with dry hydro.- gen chloride. Since'the impure hydrochloride separates,
partly as a yellow solid and partly as a cherry red viscous liquid, it is converted back to the free base and the latter is distilled at 2 mm. of mercury'from a pear-shaped flask attached to a small fractionatin'g column. After considerable low boiling forerun, 9.4 g. (which is 38% of the theoretical yield) of; the viscous yellow hydrazine di soniorncrnon NHNHaHGl Two 4 The molecular formula of the compound is C I-1 N 01. The calculated neutral equivalent is 214.8 and the neutral equivalent as found is 215. The calculated percentage of nitrogen was 13.05 and the percentage of nitrogen found was 13.09. One gram of this hydrochloride salt is sufiicient for preparing over 400 liters of the modified high alkali metol hydroquinone developer.
Since the fingerprints are developed on the film without exposing the film to light before development, it appears that. the addition of p-sec-amylphenylhydrazine hydrochloride to a high alkali metol hydroquinone developer reveals at latent sensitivity in the film, but I am unable to explain 'the'reasons for this result. It is apparently not related to the ability of the hydrazine to increase emulsion speed, for other hydrazines which are equally potent in increasing film speed fail to show the fingerprint activity.
While there may be many applications where it is desired to render a photographic fihn sensitive as described above, one very useful purpose, as has been pointed out above, is for the production of fingerprints. The method outlined herein is simpler and more pleasant than the ink method currently being used. The ridges of the finger form the dark lines on the contact print, so that a print taken according to the present invention, matches exactly with one taken'by the conventional ink method. Furthermore, the prints of a large number of people may be obtained in a very short time and the film strips may then be developed immediately or transported to a laboratory for development. Also, large numbers of prints can be permanently stored on a single film strip.
Having now fully described my invention, what I'claim as new and-desire to secure by Letters Patent is: 1'. A photographic developer containing monomethyh para-aminophenol-sulfate, hydroquinone and a minute quantity of p-sec-amylphenyIhydraZine hydrochloride."
2. A photographic developer containing monomethylpara-aminophenol-sulfate, hydroquinone, and p-sec-amyl phenylhydrazine hydrochloride in a concentration of about 2 mg. per liter.
3. A high alkali photographic developer containing monomethyl-para-aminophenol-sulfate, hydroquinone and a minute quantity of p-sec-amylphenylhydrazine hydrochloride.
4. A high alkali photographic developer containing monomethyl para aminophenol-sulfate, hydroquinone and p-sec-amylphenylhydrazine hydrochloride in a concentration of about 2 mg. per liter.
" References Cited in the file of this patent UNITED STATES PATENTS
Claims (1)
1. A PHOTOGRAPHIC DEVELOPER CONTAINING MONOMETHYLPARA-AMINOPHENOL-SULFATE, HYDROQUINONE AND A MINUTE QUANTITY OF P-SEC-AMYLPHENYLHYDRAZINE HYDROCHLORIDE.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US455073A US2879160A (en) | 1954-09-09 | 1954-09-09 | Composition for developing surface disturbances on a photographic film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US455073A US2879160A (en) | 1954-09-09 | 1954-09-09 | Composition for developing surface disturbances on a photographic film |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2879160A true US2879160A (en) | 1959-03-24 |
Family
ID=23807285
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US455073A Expired - Lifetime US2879160A (en) | 1954-09-09 | 1954-09-09 | Composition for developing surface disturbances on a photographic film |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2879160A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5798204A (en) * | 1994-07-26 | 1998-08-25 | Fuji Photo Film Co., Ltd. | Development processing method of ultrahigh-contrast black-and-white silver halide photographic material |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2028619A (en) * | 1935-03-14 | 1936-01-21 | Justin J Mccarthy | Method of obtaining fingerprints |
| US2353690A (en) * | 1942-11-11 | 1944-07-18 | Du Pont | Stabilization of organic substances |
| US2419975A (en) * | 1943-08-26 | 1947-05-06 | Eastman Kodak Co | Increasing speed and contrast of photographic emulsions |
| US2489695A (en) * | 1946-04-27 | 1949-11-29 | Hoffmann La Roche | Dihydropyrogallol |
| US2618656A (en) * | 1950-04-29 | 1952-11-18 | Eastman Kodak Co | (alkylsulfonamidoalkyl) arylhydrazines |
| US2695234A (en) * | 1951-01-26 | 1954-11-23 | Gevaert Photo Prod Nv | Photographic development |
-
1954
- 1954-09-09 US US455073A patent/US2879160A/en not_active Expired - Lifetime
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2028619A (en) * | 1935-03-14 | 1936-01-21 | Justin J Mccarthy | Method of obtaining fingerprints |
| US2353690A (en) * | 1942-11-11 | 1944-07-18 | Du Pont | Stabilization of organic substances |
| US2419975A (en) * | 1943-08-26 | 1947-05-06 | Eastman Kodak Co | Increasing speed and contrast of photographic emulsions |
| US2489695A (en) * | 1946-04-27 | 1949-11-29 | Hoffmann La Roche | Dihydropyrogallol |
| US2618656A (en) * | 1950-04-29 | 1952-11-18 | Eastman Kodak Co | (alkylsulfonamidoalkyl) arylhydrazines |
| US2695234A (en) * | 1951-01-26 | 1954-11-23 | Gevaert Photo Prod Nv | Photographic development |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5798204A (en) * | 1994-07-26 | 1998-08-25 | Fuji Photo Film Co., Ltd. | Development processing method of ultrahigh-contrast black-and-white silver halide photographic material |
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