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)
• Silver Salt Photography Or Processing Solution Therefor (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=6926308

Family Applications (1)

Country Status (5)

Cited By (5)

Citations (2)

• 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)

Also Published As

Similar Documents