US2478369A - Supersensitized silver halide photographic emulsion - Google Patents
Supersensitized silver halide photographic emulsion Download PDFInfo
- Publication number
- US2478369A US2478369A US638492A US63849245A US2478369A US 2478369 A US2478369 A US 2478369A US 638492 A US638492 A US 638492A US 63849245 A US63849245 A US 63849245A US 2478369 A US2478369 A US 2478369A
- Authority
- US
- United States
- Prior art keywords
- emulsion
- maximum
- silver
- concentration
- emulsions
- 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
- 239000000839 emulsion Substances 0.000 title description 118
- -1 silver halide Chemical class 0.000 title description 9
- 229910052709 silver Inorganic materials 0.000 title description 7
- 239000004332 silver Substances 0.000 title description 7
- 239000000975 dye Substances 0.000 description 46
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 40
- 230000035945 sensitivity Effects 0.000 description 34
- 230000003595 spectral effect Effects 0.000 description 25
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 20
- ANRHNWWPFJCPAZ-UHFFFAOYSA-M thionine Chemical compound [Cl-].C1=CC(N)=CC2=[S+]C3=CC(N)=CC=C3N=C21 ANRHNWWPFJCPAZ-UHFFFAOYSA-M 0.000 description 19
- CPELXLSAUQHCOX-UHFFFAOYSA-M Bromide Chemical compound [Br-] CPELXLSAUQHCOX-UHFFFAOYSA-M 0.000 description 16
- 230000001235 sensitizing effect Effects 0.000 description 13
- OISVCGZHLKNMSJ-UHFFFAOYSA-N 2,6-dimethylpyridine Chemical class CC1=CC=CC(C)=N1 OISVCGZHLKNMSJ-UHFFFAOYSA-N 0.000 description 12
- BSKHPKMHTQYZBB-UHFFFAOYSA-N 2-methylpyridine Chemical compound CC1=CC=CC=N1 BSKHPKMHTQYZBB-UHFFFAOYSA-N 0.000 description 11
- 230000029087 digestion Effects 0.000 description 11
- ZUNKMNLKJXRCDM-UHFFFAOYSA-N silver bromoiodide Chemical compound [Ag].IBr ZUNKMNLKJXRCDM-UHFFFAOYSA-N 0.000 description 9
- HPYNZHMRTTWQTB-UHFFFAOYSA-N dimethylpyridine Natural products CC1=CC=CN=C1C HPYNZHMRTTWQTB-UHFFFAOYSA-N 0.000 description 8
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- 125000004423 acyloxy group Chemical group 0.000 description 6
- 125000003545 alkoxy group Chemical group 0.000 description 6
- 125000004432 carbon atom Chemical group C* 0.000 description 6
- 125000005843 halogen group Chemical group 0.000 description 6
- 150000003222 pyridines Chemical class 0.000 description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 5
- 206010070834 Sensitisation Diseases 0.000 description 5
- 125000000217 alkyl group Chemical group 0.000 description 5
- 125000004414 alkyl thio group Chemical group 0.000 description 5
- 125000003118 aryl group Chemical group 0.000 description 5
- 229910052799 carbon Inorganic materials 0.000 description 5
- 230000008313 sensitization Effects 0.000 description 5
- SOSPMXMEOFGPIM-UHFFFAOYSA-N 3,5-dibromopyridine Chemical compound BrC1=CN=CC(Br)=C1 SOSPMXMEOFGPIM-UHFFFAOYSA-N 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 150000001555 benzenes Chemical class 0.000 description 4
- 125000004177 diethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- XMBWDFGMSWQBCA-UHFFFAOYSA-N hydrogen iodide Chemical compound I XMBWDFGMSWQBCA-UHFFFAOYSA-N 0.000 description 4
- SJOOOZPMQAWAOP-UHFFFAOYSA-N [Ag].BrCl Chemical compound [Ag].BrCl SJOOOZPMQAWAOP-UHFFFAOYSA-N 0.000 description 3
- 125000000623 heterocyclic group Chemical group 0.000 description 3
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical compound [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 description 3
- JYYNAJVZFGKDEQ-UHFFFAOYSA-N 2,4-Dimethylpyridine Chemical compound CC1=CC=NC(C)=C1 JYYNAJVZFGKDEQ-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 235000019441 ethanol Nutrition 0.000 description 2
- 238000010348 incorporation Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- DHKHKXVYLBGOIT-UHFFFAOYSA-N 1,1-Diethoxyethane Chemical compound CCOC(C)OCC DHKHKXVYLBGOIT-UHFFFAOYSA-N 0.000 description 1
- ITQTTZVARXURQS-UHFFFAOYSA-N 3-methylpyridine Chemical compound CC1=CC=CN=C1 ITQTTZVARXURQS-UHFFFAOYSA-N 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 239000000020 Nitrocellulose Substances 0.000 description 1
- FJWGYAHXMCUOOM-QHOUIDNNSA-N [(2s,3r,4s,5r,6r)-2-[(2r,3r,4s,5r,6s)-4,5-dinitrooxy-2-(nitrooxymethyl)-6-[(2r,3r,4s,5r,6s)-4,5,6-trinitrooxy-2-(nitrooxymethyl)oxan-3-yl]oxyoxan-3-yl]oxy-3,5-dinitrooxy-6-(nitrooxymethyl)oxan-4-yl] nitrate Chemical compound O([C@@H]1O[C@@H]([C@H]([C@H](O[N+]([O-])=O)[C@H]1O[N+]([O-])=O)O[C@H]1[C@@H]([C@@H](O[N+]([O-])=O)[C@H](O[N+]([O-])=O)[C@@H](CO[N+]([O-])=O)O1)O[N+]([O-])=O)CO[N+](=O)[O-])[C@@H]1[C@@H](CO[N+]([O-])=O)O[C@@H](O[N+]([O-])=O)[C@H](O[N+]([O-])=O)[C@H]1O[N+]([O-])=O FJWGYAHXMCUOOM-QHOUIDNNSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000011354 acetal resin Substances 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- 125000004104 aryloxy group Chemical group 0.000 description 1
- LAABTJXWUKMZIV-UHFFFAOYSA-N benzene-1,4-diol;4-(methylamino)phenol Chemical compound OC1=CC=C(O)C=C1.CNC1=CC=C(O)C=C1 LAABTJXWUKMZIV-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229920002301 cellulose acetate Polymers 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 125000003963 dichloro group Chemical group Cl* 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 125000002768 hydroxyalkyl group Chemical group 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- VRDKYJSLDJDLML-UHFFFAOYSA-N methylselenol Chemical compound [Se]C VRDKYJSLDJDLML-UHFFFAOYSA-N 0.000 description 1
- 229920001220 nitrocellulos Polymers 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 229920006324 polyoxymethylene Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 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 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
Images
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
- G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
- G03C1/08—Sensitivity-increasing substances
- G03C1/28—Sensitivity-increasing substances together with supersensitising substances
Definitions
- Supersensitization differs from hypersensitization which involves treatment of finished films or plate, an operation which normally reduces the pAg and increases the pH of the emulsion, with consequent decreased stability.
- a photographic silver halide emulsion other than a chloride emulsion e. g. silver chlorobromide, silver bromide or silver bromiodide emulsions, spectrally sensitized with a cyanine dye is supersensitized by incorporating in the emulsion certain pyridine bases.
- Our invention is directed principally to emulsions of such grain size that the emulsions give a substantially neutral-toned image in Eastman Kodak Companys D-76 developer, and. should not be confused with prior proposals to obtain blue-black tones in fine-grain emulsions by means of heterocyclic nitrogen bases.
- our invention involves incorporation of the pyridine bases in the emulsions before exposure of the emulsion and should not be confused with proposals to develop with'color-iorming developers 2 silver-salt images, in the presence of certain heterocyclic nitrogen bases which contain a reactive methyl group.
- the pyridine bases employed in practicing our invention are of a specific type and can be defined as pyridine bases containing, attached to at least one of the carbon atoms of the pyridine nucleus, a substituent selected from the group consisting of alkyl groups, alkoxyl groups, hydroxyalkyl groups, aryl groups, aryloxyl groups, alkylmercapto groups, arylmercapto groups, acyloxyl groups and halogen atoms.
- substituents selected from the group consisting of alkyl groups, alkoxyl groups, hydroxyalkyl groups, aryl groups, aryloxyl groups, alkylmercapto groups, arylmercapto groups, acyloxyl groups and halogen atoms.
- exemplary of these pyridine bases are:
- cyanine dyes which are supersensitized by these pyridine bases are characterized by the fact that the dyes produce two types of sensitization depending upon conditions. Such diiierent types of sensitization are described by Leermakers, Carroll and Staud, J. Chem. Physics 5, 878 (1937) and by G. Schwarz, Sci. et Ind. Phot. 10, 233 (1939).
- a cyanine dye of this type When a cyanine dye of this type is used as a sensitizer in low concentration, it exhibits a sensitizing maximum displaced about 20 to mu toward the red from the absorption maximum in ethyl alcohol solution.
- sensitizing .dyes Ordinarily from 10 to mg. of dye per liter of emulsion will sumce to produce the optimum sensitizing effect.
- the methods of incorporating sensitizing .dyes in emulsions are well known to those skilled in the art. Ordinarily it is preferable to dissolve the dye in a water-miscible solvent, such as methanol or ethanol, before incorporating in the emulsion.
- a water-miscible solvent such as methanol or ethanol
- the amount of pyridine base employed is not critical. Usually the full supersensitizing effect is developed at a concentration of 0.10 t0 1.5 grams per liter of emulsion. At these concerntrations practically none of the pyridine bases has an appreciable effect on the pH of the emulsion.
- the pyridine bases can be added to the emuls ons with, before or after the sensitizing dye or dyes. More than one pyridine base can be employed.
- the pyridine bases are preferably, but not necessarily, diluted with a water-miscible solvent, such as methanol, before incorporation in the emulsions.
- the sensitizing dye or dyes and the pyridine base or bases can be added to the emulsions at any convenient stage of their preparation, but preferably to the washed, finished emulsions before coating.
- Example 1 A fast negative gelatino-silver-bromiodide developing-out emulsion was sensitized with 3,3'-diethyl-9-methylselenacarboeyanine bromide (20 mg. per liter of emulsion) and to separate portions of the spectrally sensitized emulsion were added various picolines, one to each portion. A lportion of the spectrally sensitized emulsion without any picoline, and. the other portions containing the picolines, were exposed through red (Wratten No. 25) and minus blue (Wratten No.
- Example 3 A fast negative gelatinossilver bromiodide developing-out emulsion was sensitized with 3,3'-diethyl-9-methylselenacarbocyanine bromide (20 mg. per liter of emulsion) and to separate portions of the spectrally sensitized emulsion were added various lutidines, one to each portion. A portion of the spectrally sensitized emulsion without any lutidine, and the other portions containing the lutidines, were exposed through red (Wratten No. .25) and minus blue (Wratten No. 12) filters. The results are tabulated below:
- the accompanying drawing illustrates graphically the supersensitizing effect obtained with three of our new [combinations in a gelatinosilver-bromiodide emulsion.
- Each figure in the drawing is a diagrammatic reproduction of two spectrograms.
- curve A represents the sensitivity of a gelatino-silver-bromiodide emulsion containing 3,3-diethyl-Q-methylselenacarbocyanine bromide in a concentration of 20 mg. per liter of emulsion.
- Curve B represents the sensitivity of the same emulsion containing 3,3 diethyl 9 methylselenacarbocyanine bromide in a concentration of 20 mg.
- curve C represents the sensitivity of a gelatino-silver-bromiodide emulsion containing 3,3 diethyl 9 methylselenacarbocyanine bromide in a concentration of 20 mg. per liter of emulsion.
- Curve D represents the sensitivity of the same emulsion; containi g .3'-d y1- 9-methylselenacarbocyanine bromide in a concentration of 20 mg.
- curve E represents the sensitivity of a gelatino-silver-brorniodide emulsion containing 3,3 diethyl 9 methylselenacarbocyanine bromide in a concentration of 20 mg. per liter of emulsion.
- Curve F represents the sensitivity of the same emulsion containing 3,3 diethyle 9-rnethylselenacarbocyanine bromide in a concentration of 20 mg. per liter of emulsion and containing, in addition, ZA-lutidine in a concentration of 1.25 g. per liter Cif emulsion.
- Our invention is primarily directed to the customarily employed gclatino-silver-halide developing-out emulsions, such as gelatino-silverchlorobromide, gelatino-silver-br0mide and gelatino-silver-bromiodide developing-out emulsions, especially emulsions for development to blackand-white images by means of non-color-forming developers, e. g. hydroquinone-N-methyl-p-amino-phenol developers.
- non-color-forming developers e. g. hydroquinone-N-methyl-p-amino-phenol developers.
- Emulsions prepared in accordance with our invention can be coated in the usual manner upon any desired support, such as cellulose nitrate support, cellulose acetate support, polyvinyl acetal resin support, metal support, glass support or paper support.
- a photographic silver halide emulsion selected from the group consisting of silver chlorobromide, silver bromide and silver bromiodide emulsions spectrally sensitized with a sensitizing cyanine dye and containing, as a supersensitizer, a pyridine base containing on a carbon atom of the pyridine nucleus, a member selected from the group consisting of alkyl groups, alkoxyl groups, halogen atoms, acyloxyl groups, alkylmercapto groups and aryl groups of the benzene series.
- a photographic silver halide developing-out emulsion selected from a group consisting of silver chlorobromide, silver bromide and silver bromiodide developing-out emulsions spectrally sensitized with a sensitizing cyanine dye and containing, as a supersensitizer, a pyridine base containing on a carbon atom of the pyridine nucleus, a member selected from the group consisting of allryl groups, alkoxyl groups, halogen atoms, acyloxyl groups, alkylmercapto groups and aryl groups of the benzene series.
- a photographic gelatino-silver-halide developing-out emulsion selected from the group consisting of gelatino-silver-chlorobromide, gelatino-silver-bromide and gelatino-silver-bromiodide developing-out emulsions spectrally sensitized with a sensitizing cyanine dye and containing, as a supersensitizer, a pyridine base containing on a carbon atom of the pyridine nucleus, a member selected from the group consisting of alkyl groups, alkoxyl groups, halogen atoms, acyloxyl groups, alkylmercapto groups and aryl groups of the benzene series.
- a photographic gelatino-silver halide dc-- veloping-out emulsion selected from the group consisting of gelatino-silver-chlorobromide, gelatino-silver-bromide and gelatino-silver-bromiodide developing-out emulsions spectrally sensitize-d with a cyanine dye which produces a maximum of spectral sensitivity in the emulsion at one concentration and a higher concentration, or upon digestion of the emulsion containing the dye at the lower concentration, produces a second maximum of spectral sensitivity at a wave length longer than that of the first maximum, said emulsion containing, as a supersensitizer, a pyridine base containing on a carbon atom of the pyridine nucleus, a member selected from the group consisting of alkyl groups, alkoxyl groups, halogen atoms, acyloxyl groups, alkylmercapto groups and aryl
Landscapes
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- General Physics & Mathematics (AREA)
- Photoreceptors In Electrophotography (AREA)
- Plural Heterocyclic Compounds (AREA)
- Silver Salt Photography Or Processing Solution Therefor (AREA)
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
BE470786D BE470786A (sv) | 1945-12-29 | ||
US638492A US2478369A (en) | 1945-12-29 | 1945-12-29 | Supersensitized silver halide photographic emulsion |
FR942920D FR942920A (fr) | 1945-12-29 | 1946-12-27 | Perfectionnements aux émulsions photosensibles |
GB27660/47A GB636974A (en) | 1945-12-29 | 1947-10-15 | Improvements relating to photographic emulsions |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US638492A US2478369A (en) | 1945-12-29 | 1945-12-29 | Supersensitized silver halide photographic emulsion |
Publications (1)
Publication Number | Publication Date |
---|---|
US2478369A true US2478369A (en) | 1949-08-09 |
Family
ID=24560263
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US638492A Expired - Lifetime US2478369A (en) | 1945-12-29 | 1945-12-29 | Supersensitized silver halide photographic emulsion |
Country Status (4)
Country | Link |
---|---|
US (1) | US2478369A (sv) |
BE (1) | BE470786A (sv) |
FR (1) | FR942920A (sv) |
GB (1) | GB636974A (sv) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2860981A (en) * | 1956-05-21 | 1958-11-18 | Eastman Kodak Co | Supersensitization of photographic silver halide emulsions |
US2860982A (en) * | 1956-05-21 | 1958-11-18 | Eastman Kodak Co | Supersensitization of photographic silver halide emulsions |
US4049456A (en) * | 1975-04-14 | 1977-09-20 | Konishiroku Photo Industry Co., Ltd. | Light-sensitive silver halide color photographic material |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2158883A (en) * | 1937-03-29 | 1939-05-16 | Eastman Kodak Co | Photographic emulsion containing supersensitized-4'-carbocyanines |
US2186736A (en) * | 1937-07-03 | 1940-01-09 | Agfa Ansco Corp | Coupling compounds for color forming development |
-
0
- BE BE470786D patent/BE470786A/xx unknown
-
1945
- 1945-12-29 US US638492A patent/US2478369A/en not_active Expired - Lifetime
-
1946
- 1946-12-27 FR FR942920D patent/FR942920A/fr not_active Expired
-
1947
- 1947-10-15 GB GB27660/47A patent/GB636974A/en not_active Expired
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2158883A (en) * | 1937-03-29 | 1939-05-16 | Eastman Kodak Co | Photographic emulsion containing supersensitized-4'-carbocyanines |
US2186736A (en) * | 1937-07-03 | 1940-01-09 | Agfa Ansco Corp | Coupling compounds for color forming development |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2860981A (en) * | 1956-05-21 | 1958-11-18 | Eastman Kodak Co | Supersensitization of photographic silver halide emulsions |
US2860982A (en) * | 1956-05-21 | 1958-11-18 | Eastman Kodak Co | Supersensitization of photographic silver halide emulsions |
US4049456A (en) * | 1975-04-14 | 1977-09-20 | Konishiroku Photo Industry Co., Ltd. | Light-sensitive silver halide color photographic material |
Also Published As
Publication number | Publication date |
---|---|
BE470786A (sv) | |
FR942920A (fr) | 1949-02-22 |
GB636974A (en) | 1950-05-10 |
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