US3028237A - Masking of cyan images in color photography - Google Patents
Masking of cyan images in color photography Download PDFInfo
- Publication number
- US3028237A US3028237A US727043A US72704358A US3028237A US 3028237 A US3028237 A US 3028237A US 727043 A US727043 A US 727043A US 72704358 A US72704358 A US 72704358A US 3028237 A US3028237 A US 3028237A
- Authority
- US
- United States
- Prior art keywords
- cyan
- image
- red
- masking
- acid
- 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
- 230000000873 masking effect Effects 0.000 title description 12
- 239000000839 emulsion Substances 0.000 claims description 23
- 150000004985 diamines Chemical class 0.000 claims description 18
- -1 SILVER HALIDE Chemical class 0.000 claims description 17
- 229910052709 silver Inorganic materials 0.000 claims description 9
- 239000004332 silver Substances 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 8
- 150000002989 phenols Chemical class 0.000 claims description 5
- 230000003647 oxidation Effects 0.000 claims description 4
- 238000007254 oxidation reaction Methods 0.000 claims description 4
- 150000003142 primary aromatic amines Chemical class 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 2
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 12
- 239000000463 material Substances 0.000 description 10
- 238000004061 bleaching Methods 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical compound [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- 125000004432 carbon atom Chemical group C* 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- IOLCXVTUBQKXJR-UHFFFAOYSA-M potassium bromide Chemical compound [K+].[Br-] IOLCXVTUBQKXJR-UHFFFAOYSA-M 0.000 description 4
- 230000003381 solubilizing effect Effects 0.000 description 4
- BDHFUVZGWQCTTF-UHFFFAOYSA-N sulfonic acid Chemical compound OS(=O)=O BDHFUVZGWQCTTF-UHFFFAOYSA-N 0.000 description 4
- IUBPNAJDMNSDHF-UHFFFAOYSA-N 3-amino-4-(octadecylamino)benzoic acid Chemical compound C(CCCCCCCCCCCCCCCCC)NC1=C(C=C(C(=O)O)C=C1)N IUBPNAJDMNSDHF-UHFFFAOYSA-N 0.000 description 3
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 3
- 229910021607 Silver chloride Inorganic materials 0.000 description 3
- 125000002843 carboxylic acid group Chemical group 0.000 description 3
- 238000000354 decomposition reaction Methods 0.000 description 3
- 239000000975 dye Substances 0.000 description 3
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N phenol group Chemical group C1(=CC=CC=C1)O ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 3
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 3
- 125000001424 substituent group Chemical group 0.000 description 3
- AEWZMTVRFCTONS-UHFFFAOYSA-N 3-amino-4-(octadecylamino)benzenesulfonic acid Chemical compound CCCCCCCCCCCCCCCCCCNC1=CC=C(S(O)(=O)=O)C=C1N AEWZMTVRFCTONS-UHFFFAOYSA-N 0.000 description 2
- RPKWNMFDAOACCX-UHFFFAOYSA-N 4-chloro-3-nitrobenzenesulfonic acid Chemical compound OS(=O)(=O)C1=CC=C(Cl)C([N+]([O-])=O)=C1 RPKWNMFDAOACCX-UHFFFAOYSA-N 0.000 description 2
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 2
- REYJJPSVUYRZGE-UHFFFAOYSA-N Octadecylamine Chemical compound CCCCCCCCCCCCCCCCCCN REYJJPSVUYRZGE-UHFFFAOYSA-N 0.000 description 2
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 230000000295 complement effect Effects 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 150000004780 naphthols Chemical class 0.000 description 2
- 125000000449 nitro group Chemical group [O-][N+](*)=O 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 2
- 159000000000 sodium salts Chemical class 0.000 description 2
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 2
- 125000000542 sulfonic acid group Chemical group 0.000 description 2
- AYLDJQABCMPYEN-UHFFFAOYSA-N (4-azaniumylphenyl)-diethylazanium;sulfate Chemical compound OS(O)(=O)=O.CCN(CC)C1=CC=C(N)C=C1 AYLDJQABCMPYEN-UHFFFAOYSA-N 0.000 description 1
- DFXQXFGFOLXAPO-UHFFFAOYSA-N 96-99-1 Chemical compound OC(=O)C1=CC=C(Cl)C([N+]([O-])=O)=C1 DFXQXFGFOLXAPO-UHFFFAOYSA-N 0.000 description 1
- 241000766754 Agra Species 0.000 description 1
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 206010034960 Photophobia Diseases 0.000 description 1
- 239000007868 Raney catalyst Substances 0.000 description 1
- NPXOKRUENSOPAO-UHFFFAOYSA-N Raney nickel Chemical compound [Al].[Ni] NPXOKRUENSOPAO-UHFFFAOYSA-N 0.000 description 1
- 229910000564 Raney nickel Inorganic materials 0.000 description 1
- KEAYESYHFKHZAL-UHFFFAOYSA-N Sodium Chemical compound [Na] KEAYESYHFKHZAL-UHFFFAOYSA-N 0.000 description 1
- 239000004133 Sodium thiosulphate Substances 0.000 description 1
- 229960000583 acetic acid Drugs 0.000 description 1
- 150000001299 aldehydes Chemical class 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- 150000003863 ammonium salts Chemical class 0.000 description 1
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 description 1
- 229910052794 bromium Inorganic materials 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- ZCDOYSPFYFSLEW-UHFFFAOYSA-N chromate(2-) Chemical compound [O-][Cr]([O-])(=O)=O ZCDOYSPFYFSLEW-UHFFFAOYSA-N 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 150000001989 diazonium salts Chemical class 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- YAGKRVSRTSUGEY-UHFFFAOYSA-N ferricyanide Chemical compound [Fe+3].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-] YAGKRVSRTSUGEY-UHFFFAOYSA-N 0.000 description 1
- 239000012362 glacial acetic acid Substances 0.000 description 1
- 125000005843 halogen group Chemical group 0.000 description 1
- 208000013469 light sensitivity Diseases 0.000 description 1
- 150000002828 nitro derivatives Chemical class 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 229910000027 potassium carbonate Inorganic materials 0.000 description 1
- KMUONIBRACKNSN-UHFFFAOYSA-N potassium dichromate Chemical compound [K+].[K+].[O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O KMUONIBRACKNSN-UHFFFAOYSA-N 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 150000003141 primary amines Chemical class 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 229960001407 sodium bicarbonate Drugs 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- 235000010265 sodium sulphite Nutrition 0.000 description 1
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 1
- 235000019345 sodium thiosulphate Nutrition 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 150000003458 sulfonic acid derivatives Chemical class 0.000 description 1
- 239000003799 water insoluble solvent Substances 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
- G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
- G03C7/18—Processes for the correction of the colour image in subtractive colour photography
Definitions
- An essential disadvantage of the recoupling process is that the layers which are dyed from the outset lower the light sensitivity of the silver halide. This is especially so when interchange of the layers, desirable for other reasons, is carried out, for example where a red-dyed layer for masking the cyan image is arranged above the greensensitive layer.
- a red masking image for the cyan partial image can be obtained in a very simple manner and without the disadvantages referred to if one or more diaminesof the general formula are incorporated into the layer along with the cyan coupler, R in this general formula representing a straight or branched chain alkyl radical, for example with at least 6, preferably 10 to carbon atoms and R representing a solubilizing group, for example a sulfonic acid or carboxyl group.
- Orthodiamines of this type are inert with respect to the color developing bath but in a subsequent silver bleaching bath, for example with potassium ferricyanide, undergo an oxidizing reaction with the residual cyan coupler to give red dyestufis, so that, during the conventional processing and without additional measures or baths being necessary, a red correcting image is formed with a gradation opposite to that of the cyan image, that is to say a positive red masking image in case that the cyan image is negative and a negative red masking image in case that the cyan image is positive.
- the optimal density of the red masking image can easily be obtained by adding an appropriate proportion of the diamine to the silver halide emulsion layer, whereas this is not readily possible when colored couplers are used.
- the diamines are preferably applied in amounts of 1-6 g. and the cyan color coupler in amounts of 520 g. per 1 kg. of silver halide emulsion.
- Suitable diamines are:
- the diamines can be produced in known manner by the replacement of substituents, such as chlorine or bromine, in the ortho-position to the nitro group by the radical of a primary amine and subsequent reduction of the nitro group to the amino group.
- substituents such as chlorine or bromine
- 4-octadecylarnino-3-amino-benzene sulphonic acid is formed from 4-chloro-3-nitrobenzene sulphonic acid by the use of stearyl amine and subsequent reduction.
- the oxidizing bath necessary for forming the red masking image corresponds to the potassium ferricyanide bleaching baths usual for color development.
- Example 1 100 g. of a red-sensitive silver bromide emulsion, which contains 1.2 g. of 3-(l'-hydroxy-2'-naphthoyl)-amino-4- methyl octadecylaminobenzene sulphonic acid or a water soluble salt thereof, such as the sodium-, potassiumor ammonium salt, and 0.3 g. of 4-octadecylamino-3-aminobenzoic acid, is cast on to a support, and the resulting material is dried, exposed and processed in the following baths.
- a red-sensitive silver bromide emulsion which contains 1.2 g. of 3-(l'-hydroxy-2'-naphthoyl)-amino-4- methyl octadecylaminobenzene sulphonic acid or a water soluble salt thereof, such as the sodium-, potassiumor ammonium salt, and 0.3 g. of 4-octadecy
- a negative cyan image and a positive red correcting image are formed in the processed layer.
- 3-nitro-4-octadecylamino-benzoic acid is produced in analogous manner as the corresponding sulfonic acid derivative disclosed in Example 4 below, by replacing the Z-nitro-1-chlorobenzene-4-sulfonic acid by the equivalent amount of 4-chloro-3-nitro-benzoic acid.
- the aminated nitro compound thereby formed is catalytically reduced in the presence of Raney-nickel in met-hanolic solution.
- the aforementioned diamino compound may be replaced by the equivalent amount of 3-arnino-4-dodecylamino-benzoic acid which is obtained in analogous manner as the octadecylderivative. Point of decomposition 194 C.
- Example 2 A green-sensitive silver bromide emulsion, containing 1.2 g. of 1-(4-phenoxy-3-sulphophenyl)-3-heptadecyl pyrazolone per 100 g., is cast on to the red-sensitive layer referred to in Example 1. Another layer which contains colloidal silver as yellow filter is cast thereon, followed by an optically non-sensitized silver bromide emulsion containing 1.5 g. of -(4-(stear0ylamino)-benzoyl acetarnino)-isophthalic acid per 100 g. After exposure and processing as in Example 1, a negative and complementary color image is formed, the cyan layer of which also contains a positive red masking image.
- Example 3 The multi-layer material cast as described in Example 2 is modified by interchanging the red-sensitive and greensensitive layers. After the modified material has been exposed and processed in the same way as in Example 2, practically no loss in sensitivity of the green-sensitive layer is found, although in this case the red mask is above the green-sensitive layer.
- Example 4 An optically non-sensitized silver bromide emulsion containing 1.4 g. of 3-(p-anisoyl acetamino)-4-methyl octadecylaminobenzoic acid per 100 g. is cast on to a support and dried. A green-sensitized silver chloride emulsion containing 1.4 g. of 1-phenyl-3-heptadecyl-5- pyrazolone-3'-su1phonic acid per 100 g. is coated above the silver bromide emulsion. A red-sensitized silver chloride emulsion with 1.1 g.
- the cyan couplers to be used for carrying out the process of the present invention are well known in the art. They are derivatives of phenol or u-naphthol having in ortho or para-position to the phenolic hydroxy group a coupling function. Such phenolic compounds are either unsubstituted in the aforementioned positions or they are substituted by substituents which are split off during coupling with the oxidation products of the lCOlOI' forming developers such as primary aromatic amino compounds, such substituents being preferably sulfonic acid groups or halogen atoms. Such couplers are preferred which are fast to diffusion, this property being for instance obtained by the presence of higher alkyl radicals having for instance 10 to 20 carbon atoms.
- couplers may contain solubilizing groups such as sulfonic acid or carboxylic acid groups.
- solubilizing groups such as sulfonic acid or carboxylic acid groups.
- couplers are for instance disclosed in US. Patents 2,184,849; 2,324,832; 2,357,395 and 2,366,324.
- the couplers and/or the diamines may also be incorporated in a water permeable, water insoluble solvent as described for instance in US. Patents 2,304,940 and 2,322,027 before they are added to the gelatino silver halide emulsions.
- bleaching bath which is used for carrying out the process of the present invention it is preferred to use aqueous solutions of water soluble ferricyanides, the pH value of said solutions being adjusted to about 5 to 8 and the concentration to about 2 to 10 percent by weight.
- aqueous solutions of potassium bichromate customary in the art as for instance aqueous solutions of potassium bichromate.
- a photographic material comprising a silver halide emulsion layer containing a cyan coupler selected from the class consisting of phenols and naphthols that couple with the oxidation products of a primary aromatic amine developer in a position orthoand parato the phenolic hydroxy group of the coupler to form a cyan dye, and a diamine of the general formula Where R represents an alkyl radical having at least 6 carbon atoms and R represents a solubilizing group selected from the class consisting of sulfonic acid and carboxylic acid groups, said coupler having a concentration of from S to 20 grams per kilogram of emulsion and the diamine having a concentration of from 1 to 6 grams per kilogram of emulsion.
- a cyan coupler selected from the class consisting of phenols and naphthols that couple with the oxidation products of a primary aromatic amine developer in a position orthoand parato the phenolic hydroxy group of the coupler to form a cyan dye
- R represents an alkyl
- a photographic material according to claim 5 wherein the diamine is 4-octadecylamino-3-arninobenzene sulphonic acid.
- a photographic material according to claim 5 wherein the diamine is 4-octadecylamino-3-aminobenzoic acid.
- a photographic material according to claim 5 wherein the diamine is 4-dodecylamino-3-aminobenzoic acid.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Silver Salt Photography Or Processing Solution Therefor (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEA27031A DE1034022B (de) | 1957-04-26 | 1957-04-26 | Verfahren zur Herstellung von roten Masken fuer das blaugruene Teilbild in farbphotographischen Materialien |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3028237A true US3028237A (en) | 1962-04-03 |
Family
ID=6926308
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US727043A Expired - Lifetime US3028237A (en) | 1957-04-26 | 1958-04-08 | Masking of cyan images in color photography |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US3028237A (en)) |
| BE (1) | BE567154A (en)) |
| CH (1) | CH374892A (en)) |
| DE (1) | DE1034022B (en)) |
| FR (1) | FR1195079A (en)) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3178286A (en) * | 1959-11-05 | 1965-04-13 | Gevaert Photo Prod Nv | Light sensitive photographic color element |
| US3186840A (en) * | 1958-12-11 | 1965-06-01 | Agfa Ag | Direct positive colored photographic elements containing dihydrazones and process for forming colored masks therefrom |
| US3245787A (en) * | 1959-11-13 | 1966-04-12 | Gevaert Photo Prod Nv | Production of color photographic images |
| US3249431A (en) * | 1960-03-29 | 1966-05-03 | Gevaert Photo Prod Nv | Production of color photographic images |
| US3535113A (en) * | 1966-01-18 | 1970-10-20 | Agfa Gevaert Nv | Production of color masking images using p-phenylenediamine mask-forming compounds |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2697662A (en) * | 1951-07-24 | 1954-12-21 | Du Pont | Color correction processes |
| US2805158A (en) * | 1952-10-11 | 1957-09-03 | Ici Ltd | Process for colour photography |
-
0
- BE BE567154D patent/BE567154A/xx unknown
-
1957
- 1957-04-26 DE DEA27031A patent/DE1034022B/de active Pending
-
1958
- 1958-04-08 US US727043A patent/US3028237A/en not_active Expired - Lifetime
- 1958-04-09 CH CH5807358A patent/CH374892A/de unknown
- 1958-04-25 FR FR1195079D patent/FR1195079A/fr not_active Expired
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2697662A (en) * | 1951-07-24 | 1954-12-21 | Du Pont | Color correction processes |
| US2805158A (en) * | 1952-10-11 | 1957-09-03 | Ici Ltd | Process for colour photography |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3186840A (en) * | 1958-12-11 | 1965-06-01 | Agfa Ag | Direct positive colored photographic elements containing dihydrazones and process for forming colored masks therefrom |
| US3178286A (en) * | 1959-11-05 | 1965-04-13 | Gevaert Photo Prod Nv | Light sensitive photographic color element |
| US3245787A (en) * | 1959-11-13 | 1966-04-12 | Gevaert Photo Prod Nv | Production of color photographic images |
| US3249431A (en) * | 1960-03-29 | 1966-05-03 | Gevaert Photo Prod Nv | Production of color photographic images |
| US3535113A (en) * | 1966-01-18 | 1970-10-20 | Agfa Gevaert Nv | Production of color masking images using p-phenylenediamine mask-forming compounds |
Also Published As
| Publication number | Publication date |
|---|---|
| CH374892A (de) | 1964-01-31 |
| DE1034022B (de) | 1958-07-10 |
| BE567154A (en)) | |
| FR1195079A (fr) | 1959-11-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3061432A (en) | Pyrazolino benzimidazole color coupler | |
| US2600788A (en) | Halogen-substituted pyrazolone couplers for color photography | |
| US2860974A (en) | Photographic color correction process | |
| US2414491A (en) | Photographic developer | |
| US3002836A (en) | Cyan color former for color photography | |
| US2362598A (en) | Color forming compounds containing sulphonamide groups | |
| US2976146A (en) | Novel cyan-forming couplers | |
| US3245787A (en) | Production of color photographic images | |
| US3028237A (en) | Masking of cyan images in color photography | |
| US3556796A (en) | Silver halide emulsion containing naphthol colour couplers for cyan | |
| US3186840A (en) | Direct positive colored photographic elements containing dihydrazones and process for forming colored masks therefrom | |
| EP0071570A1 (en) | Process for the production of a photographic black dye image | |
| DE2526112A1 (de) | Zweiwertige purpurkuppler und deren verwendung | |
| US3047385A (en) | Production of color photographic images | |
| US2823998A (en) | Process and material for producing photographic multi-color images | |
| US2979405A (en) | Light-sensitive photographic element containing a 1-hydroxy-2-naphthoic acid anilidecolor coupler | |
| US3671257A (en) | Color silver halide photographic material containing yellow-colored magenta-forming color coupler | |
| US2688538A (en) | Photographic elements and process of color correction utilizing styryl dyes as couplers | |
| US2805158A (en) | Process for colour photography | |
| US3615602A (en) | Color-photographic silver halide emulsion containing colored cyan-forming couplers | |
| US2663638A (en) | Color correction of multicolor film by integral styryl dye masking images | |
| US3447923A (en) | Color photographic process | |
| US2701766A (en) | Developers for and method of producing phenazonium dyestuff images with p-dialkylaminoaniline developing agents | |
| GB698047A (en) | Colour photography | |
| US2725291A (en) | Azo dye couplers having two coupling nuclei |