US2689793A - Controlling grain and contrast in color photography - Google Patents

Controlling grain and contrast in color photography Download PDF

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Publication number
US2689793A
US2689793A US342066A US34206653A US2689793A US 2689793 A US2689793 A US 2689793A US 342066 A US342066 A US 342066A US 34206653 A US34206653 A US 34206653A US 2689793 A US2689793 A US 2689793A
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United States
Prior art keywords
color
coupler
emulsion
emulsion layer
silver halide
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Expired - Lifetime
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US342066A
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English (en)
Inventor
William R Weller
Nicholas H Groet
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Eastman Kodak Co
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Eastman Kodak Co
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Publication date
Priority to DENDAT962666D priority Critical patent/DE962666C/de
Priority to BE527178D priority patent/BE527178A/xx
Application filed by Eastman Kodak Co filed Critical Eastman Kodak Co
Priority to US342066A priority patent/US2689793A/en
Priority to GB6768/54A priority patent/GB755655A/en
Priority to FR1103430D priority patent/FR1103430A/fr
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Publication of US2689793A publication Critical patent/US2689793A/en
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    • 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
    • G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials
    • G03C7/32—Colour coupling substances
    • 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
    • G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials

Definitions

  • This invention relates to a process for controlling the graininess, sharpness and contrast characteristics of dye images in color photography.
  • the dye images are produced in silver halide emulsion layers by exposing to colored subjects and developing the resulting latent images with a primary aromatic amino silver halide developing agent in the presence of coupler compounds which react with the oxidized developing agent to form dyes.
  • a primary aromatic amino silver halide developing agent in the presence of coupler compounds which react with the oxidized developing agent to form dyes.
  • the dyes which are formed generally have relatively very high covering power.
  • a dye image prepared by color development exhibits a much higher density to light in the wavelength region corresponding to its absorption band than does a silver image.
  • a conventional emulsion layer which on normal blackan'd-white processing yields a normal contrast silver imageproduces a dyeimage on color development which has such excessive contrast that it is not usable in a color photographic process.
  • One object of our invention is to provide a process for obtaining dye images with improved graininess and sharpness characteristics.
  • a further object is to provide a method for obtaining dye images of normal contrast by color development of silver halide emulsion layers which contain amounts of silver halide in excess of that required for the production of dye images by conventional color development procedures.
  • the objects of our invention are preferably accomplished by using, for the formation of colored photographic images, silver halide emulsion layers containing amounts of silver halide in excess of those required to produce images of normal contrast when conventional color development is carried out, and conducting the color development of such emulsionlayers in the presence of a compound, referred to hereinafter as a competing, coupler, which competes with another coupler present for the oxidized developer.
  • the competing couplers appear to react with the oxidized developing agent to produce a dye which is soluble and removable from the emulsion layer by washing.
  • the first type of such processes makes use of couplers which are soluble in the color developer solution and which are diffusible into the silver halide emulsion layers.
  • the dye-forming reactions occur between two components of the color developer solution to produce a dye which is insoluble and/or nondiffusible.
  • nondifiusing couplers are incorporated in the silver halide emulsion layers and the coupling reactions occur between these incorporated couplers and the primary aromatic amino developing agent supplied from thecolor developer solution as shown in Mannes et al. U. S. Patent 2,304,940 and Jelley and Vittum U. S. Patent 2,- 322,027.
  • Our invention is applicable to both types of color processes.
  • the color developer solution contains the color developing agent, the dye-image-forming coupler, andthe competing coupler.
  • the developer solution contains the color .developing agent and the competing coupler, or alternatively, the competing coupler can also be. incorporated in the silver halide emulsion layers.
  • diifusible coupler is meant one which can be incorporated in the developer and which forms a soluble dye which quickly diffuses out of the emulsion layer
  • soluble but non-diffusing coupler is meant one which can be incorporated in the developer, but forms a comparatively permanent, nondiffusing dye.
  • a fast coarse-grained red -light-sensitive emulsion is. prepared and a non-diffusing coupler compound 2-(diamylphenoxyacetamido)- 4,6-dichloro-5-methyl phenol is dispersed therein by the methods of the above J elley and Vittum invention.
  • concentration of silver halide and coupler compound in the emulsion are so adjusted thatwhen the emulsion is coated on to a suitable film base, 60 milligrams of coupler and 30 milligrams of silver halide (calculated as silver) are obtained per square foot of coating. This represents a quantity of silver halide which will yield, upon color development a cyan dye imageof useful contrast although having more grain than desired.
  • Thezemulsion-layer isthen' exposed to the red aspect of a colored subject and developed for 9 minutes in an ordinary color-forming developer solution such as that shown in the mentioned patent but devoid of coupler compounds. Development is then followed ;by. removal. of the silverimage; obtained during development to yield".
  • a cyan dye image, the contrast of which is illustrated by the density-log E curve 1 of the drawings. The contrast of. this image .is comparable to contrasts of dye images obtained in widely used color processes; however, the graininess of the cyan dye image is more than desired.
  • a similar emulsion is prepared in the manner of the mentioned patent having a considerably higher silver halide concentration per unit area such that when it is coated on to a film base the silver concentration is 400 milligrams per square foot and the coupler concentration 60 milligrams per square foot of coating (the same coupler concentration as that. ofthe first-emulsionprepared above).
  • Curve 2 shows the high; contrast of the cyan dye image obtained by increasingthezsilven concentration of the emulsion. from 30 to 400: milligrams per square. foot.
  • layer color elements each. containing: .lIlLlthGLIGI-X spective emulsion layers, .substantiallyz non-J, diffusing coupler compounds were-prepared .:by the methods of the aboveU; S.Patentsz2,30.4,940 and 2,322,027.
  • the two elements were similar. in all respects except thatweachemulsiomlayer of the first element contained; from-.twoatortour. times as much silver halide'asstheucorresponding emulsion layer ofthe second element.
  • Thetwo. elements were then exposed toa. colored-subject and. developed in a blacheandt-white developer:- Following reversaliexposure: each. element was then developed under the same conditions ina colorv developer.
  • the color. developer for the first element was modified solely by. adding .075 g. -per-liter 0t 1-naphtol+3,6,8-trisulfonic acid. l Theelementswere then: both subjected to the usual silverbleachaandfixing steps..: Under:these processin-gconditions the twocoatings gave dye images havingvery nearly the same contrast and color balance; however, the first element which had higher silver content and which was developed in the color developer containing the diiiusible coupler compound, showed about .4 log E higher speed, much higher sharpness and definition, and less graininess than the second element.
  • Our process is primarily designed for, although not limited to use in systems of color photography employing superposed emulsion layers sensitized to the primary regions of the visible spectrum and containing in the respective emulsion layers non-diifusing coupler compounds yielding differently colored dye images.
  • our invention is employed as described with these superimposed emulsion layers and development is carried out in a color-forming developer composition containing a soluble competing coupler yielding a diifusible dye, the contrast and grain characteristics of the dye images in all emulsion layers are improved substantially as illustrated in the drawings.
  • the silver halide concentration per unit area of the emulsion layers employed in our invention is that necessary to reduce the contrast and grain to the desired value and can be varied within rather wide limits depending upon the result desired and the particular process which is under consideration.
  • Substantial improvement in grain characteristics is obtained by using at least about 50 milligrams per square foot of emulsion and preferably about 2 to 25 times the usual silver halide concentration of incorporated coupler processes, or from about 50' to 750 milligrams of silver halide (calculated as silver) per square foot of emulsion.
  • the emulsions contain substantially more than about .50 milligrams silver per square foot, normal color development in absence of diffusible coupler compounds yields greater contrast than usually desired in color processes.
  • the quantity of competing diifusible coupler which is used in the color developing compositions is dependent upon a number of factors.
  • One of these is the relative coupling activity of the non diffusible couplers compared to that of the diffusible competing couplers.
  • a suitable type and quantity of competing coupler can be readily ascertained.
  • Another factor is the contrast desired in the particular color process under consideration. That is, in a color printing process a contrast of 2.5 may be desired, whereas in a negative color process such as illustrated in the above example, a contrast of only about 0.7 may be desired.
  • More competing diffusible coupler can be employed in conjunction with the latter process to effect a greater reduction in contrast.
  • these color films may contain in the respective emulsion layers non-diiiusible couplers of different coupler activity. Therefore, the relative increase in the silver halide concentration required in the emulsion layers may differ depending upon the coupling characteristics of the couplers in each emulsion layer.
  • diifusible coupler compound, I-I-acid, employed in the above example is especially efficacious for use in the process of our invention.
  • suitable diifusible coupler compounds are the following:
  • our invention can be used in conjunction with many types of emulsion layers regardless of silver halide concentration, to efifect contrast and grain favorably. While the faster and coarser grained emulsions of the concentration indicated are particularly adapted to use in our process, for some purposes the finergrained emulsions can be used but the alteration in contrast and grain of the dye images obtained therefrom is less pronounced.
  • the invention is particularly applicable to use in conjunction with multilayer color films containing colored color-forming coupler compounds such as disclosed in U. S. Patents 2,428,054 and 2,449,966.
  • mixed grain photographic elements such as described. in U. S. Patents 2,490,749 and 2,490,751, are adapted to use in our process for the mentioned purposes by utilizing coupler-containing mixed grain emulsions having silver halide concentrations of the order indicated and developing such emulsions with color developer compositions containing diffusible coupler compounds such as illustrated.
  • the soluble couplers forming diffusible dyes such as mentioned can be used in color developing compositions also containing soluble coupler compounds forming substantially non-diffusible dyes.
  • the non-diffusible dyes then remain in the photographic layer forming the color photographic image whereas the diifusible dye images formed along with them in color development leach out of the photographic layers in washing.
  • the mentioned sulfonated naphthol types of couplers are more useful than couplers such as the simple mono and polyhydric phenols.
  • Such developer compositions are particularly useful for the development of dye images in emulsion layers devoid of coupler compounds; however, the effect obtained may be somewhat diiferent than the case when the diifusible coupler is in the de- .ifine-graini dye imagesiin”processesnnormally emip'loying i only lolack andswhite rmalterials iLBJIId -processing. "For example,ninprocesses ain which iafsfineiagraina silver rimage' iiseiusuallywemployed it was found that our process couldtfb uusedito obtain the. requisite .finegrain..-image with.
  • a process for preparingcolored photographic "images-Which comprises exposing to a subject a li-ght s'ensitive silver 'halide emulsion layer containing anon-diffusing coupler compound, developing the exposedemul'sion layer-With a-colordeveloping solution containing a mixture of a primary aromatic amino silver halide developing agentan'd a diif-usible'coupler compound, to obtain in the exposed-region of the emulsion layer both a non difiusibledye image" from the nondifiusible-coupler and a 'diffusi'ble-dye imagefrom the di-ifusible coupler, and" Washing the difi'usible dye image" from the emulsion layer.
  • a process for preparing colored photographic 4 "images which comprises exposing to a subject a light-sensitive silver halide emulsion layer containing a non-diffusing. coupler compound, which emulsion is developable with a'solution or a, primary aromatic amino silver halide "developing agent to a contrast higher than that. of the color 4 process, developing the exposed emulsion layer .With.saidrcolondeveloping solution containing a mixture of said developing agentland sufficient .difiusible coupler compound to obtain in' the ex- ,.posed regions of the emulsion layer-a non-diffusi- ..ble.idye image having. the contrast .of. the, process and a 'di'ifusible ldye image, and washing'the diffusible dye? image fromithe emulsion layer.
  • a process for preparing colored photographic images which comprises exposing to a'subject a- .light sensitive.silver'halide emulsion layer containing .a non-diffusing coupler compound sand atlleast about "50 mg. of silver as silver halide .per sq. ft. of emulsion, which emulsion isdevelopable With a solution of a primaryv aromatic amino silver? halide. developing agent to a contrast higher than that of the color process, developing the exposed emul'sionlayer with.
  • said color-developing..solutionv containing a mixture of said develop-ingoage-nt and sufficient .difiusible coupler compound to obtain inthe exposed .regio-ns of the emulsion i layer a .non .dii fusible -.d.ye .-.image having the contrast of the .pr'ocess and. adiffusi- .xble dye image, and washingtheclifiusible-v dye. image from the emulsion layer.
  • a process for preparing coloredv photographic 2 images which comprisesrexposingto. a.-subje'ct Ia .1igh13eiSBIlSltlV8 silver .z ha'lide' 'emulsioni layer a-containing .a nonedifiusing: coupler Icomp-oun'dg and 7 i'fromiabout 50 to 750::ngnof silver-as silver halide 'Jpensq; it.
  • iof' emulsiom' which emulsion is develop- .iable with a solution of a' primary 1 aromatic amino s'silver h'a'lidedevelopingiagent'to a contrast higher :thanilthat of'themolor processg developing the exposed emulsion. :layer with said" color-develop- .ing .2 solution 2'. containing a mixture :of said developing :agent and sufficient diffusible "coupler :-compound'to obtain in the exposed regions of 0 thei' emulsion layer a non-diffusible dye image :"h'aving. the contrastofr the process and, a diffusibleidye'image, and washing the clifl usible -dye image' frcm" the emulsion layer.
  • process'for preparing colored photographic 5 iima'ges which comprises exposing toa suloject -a Jlightsensitive 1 silver "halide emulsion layer containing ainon difiusing coupler compound, Which --emulsion is i developable with a solution of a ;:.primary aromatic amino silver halide developing 0 agent to a contrast higher than that ofthe color i'process, developingthe exposed emulsion layer with said coloredeveloping solution-containing "a mixture -of said -developing"agent and sufii'cient diffusi'blercoupler compound containing a group obtain in the exposed regions of the emulsion layer a non-difiusible dye image having the contrast of the process and a difi'usible yellow dye image, and washing the diffusible yellow dye image from the emulsion layer.
  • a process for preparing colored photographic images which comprises exposing to a subject a light-sensitive silver halide emulsion layer containing a non-diffusing coupler compound, which emulsion is developable with a solution of a primary aromatic amino silver halide developing agent to a contrast higher than that of the color process, developing the exposed emulsion layer with said color-developing solution containing a mixture of said developing agent and sufficient difiusible coupler compound containing a naphthol sulfonic acid group to obtain in the exposed regions of the emulsion layer a non-difiusible dye image having the contrast of the process and a diffusible cyan dye image and washing the diffusible cyan dye image from the emulsion layer.
  • a process for preparing colored photographic images which comprises exposing to a subject a light-sensitive silver halide emulsion layer containing a non-diffusing coupler compound, which emulsion is developable with a solution of a primary aromatic amino silver halide developing agent to a contrast higher than that of the color process, developing the exposed emulsion layer with said color-developing solution containing a mixture of said developing agent and sufiicient diffusible coupler compound of the class consisting of 1-naphthol-5-sulfonic acid, 1 p sulfophenyl-3-methyl-5-pyrazolone, 1 phenyl-3-metasulfo-benzamido-5-pyrazolone, l-amino-B-naphthol 3,6 disulfonic acid, 2- amino-5-naphthol-7-sulfonic acid, 1,8-dihydroxy-naphthalene disulfonic acid, l-naphthol- 3,6,8
  • a process for preparing colored photographic images which comprises exposing to a subject a light-sensitive silver halide emulsion layer containing a non-diffusing coupler compound, which emulsion is developable with a solution of a primary aromatic amino silver halide developing agent to a contrast higher than that of the color process, developing the exposed emulsion layer with said color-developing solution containing a mixture of said developing agent and sufiicient 1-amino-8-naphthol-3,6- disulfonic acid to obtain in the exposed regions ll) of the emulsion layer a non-diffusing dye image having the contrast of the process and a diffusible cyan dye image, and washing the diifusible dye image from the emulsion layer.
  • a process for preparing colored photographic images which comprises exposing to a subject a light-sensitive silver halide emulsion layer containing a non-diffusing coupler compound which emulsion is developable with a solution of a primary aromatic amino silver halide developing agent to a contrast higher than that of the color process, developing the exposed emulsion layer with said color-developing solution containing a mixture of said developing agent and sufficient 1-naphthol-3,6,8-trisulfonic acid to obtain in the exposed regions of the emulsion layer a non-diffusing dye image having the contrast of the process and a diffusible cyan dye image, and washing the diffusible dye image from the emulsion layer.
  • a method for preparing colored photographic images which comprises exposing to a subject a light-sensitive silver halide emulsion layer, developing the exposed emulsion layer with a color-developing solution containing a primary aromatic amino silver halide developing agent, a coupler compound forming a non-diffusing dye image in the emulsion layer, and a coupler compound containing a sulfonated naphthol group forming a difiusible dye image in the emulsion layer, and Washing the difiusible dye image from the emulsion layer.
  • a process for preparing a colored photographic image in an exposed silver halide emulsion layer containing a non-difiusing coupler compound which comprises developing the exposed emulsion layer with a color-developing solution containing a mixture of a primary aromatic amino silver halide developing agent and a diffusible coupler compound, to obtain in the exposed region of the emulsion layer both a non-diffusible dye image from the non-clifiusible coupler and a diffusible dye image from the diifusible coupler, and washing the diffusible dye image from the emulsion layer.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
US342066A 1953-03-13 1953-03-13 Controlling grain and contrast in color photography Expired - Lifetime US2689793A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
DENDAT962666D DE962666C (de) 1953-03-13 Verfahren zur Herstellung von farbenphotographischen Bildern nach dem Farbentwicklungsverfahren
BE527178D BE527178A (enrdf_load_stackoverflow) 1953-03-13
US342066A US2689793A (en) 1953-03-13 1953-03-13 Controlling grain and contrast in color photography
GB6768/54A GB755655A (en) 1953-03-13 1954-03-09 Process of colour development in colour photography
FR1103430D FR1103430A (fr) 1953-03-13 1954-03-13 Procédé de photographie en couleurs

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Application Number Priority Date Filing Date Title
US342066A US2689793A (en) 1953-03-13 1953-03-13 Controlling grain and contrast in color photography

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US2689793A true US2689793A (en) 1954-09-21

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US342066A Expired - Lifetime US2689793A (en) 1953-03-13 1953-03-13 Controlling grain and contrast in color photography

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US (1) US2689793A (enrdf_load_stackoverflow)
BE (1) BE527178A (enrdf_load_stackoverflow)
DE (1) DE962666C (enrdf_load_stackoverflow)
FR (1) FR1103430A (enrdf_load_stackoverflow)
GB (1) GB755655A (enrdf_load_stackoverflow)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2994610A (en) * 1956-09-26 1961-08-01 Agfa Ag Color radiography
US2998314A (en) * 1956-09-18 1961-08-29 Agfa Ag Color photography
US3132946A (en) * 1960-01-11 1964-05-12 Eastman Kodak Co Contact screens for photogravure
US3227554A (en) * 1959-04-06 1966-01-04 Eastman Kodak Co Photographic elements and processes utilizing mercaptan-forming couplers
JPS5096216A (enrdf_load_stackoverflow) * 1973-12-24 1975-07-31
US4002477A (en) * 1973-11-28 1977-01-11 Eastman Kodak Company Diffusion transfer processes and elements using or containing inert transitional metal complex oxidizing agents
JPS5250230A (en) * 1975-10-20 1977-04-22 Fuji Photo Film Co Ltd Method for forming color photographic image
US4284714A (en) * 1979-05-09 1981-08-18 Fuji Photo Film Co., Ltd. Method of forming a photographic image

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2454001A (en) * 1945-11-08 1948-11-16 Gen Aniline & Film Corp Control of contrast with aromatic diamine color developers

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2998314A (en) * 1956-09-18 1961-08-29 Agfa Ag Color photography
US2994610A (en) * 1956-09-26 1961-08-01 Agfa Ag Color radiography
US3227554A (en) * 1959-04-06 1966-01-04 Eastman Kodak Co Photographic elements and processes utilizing mercaptan-forming couplers
DE1422836B1 (de) * 1959-04-06 1970-04-30 Eastman Kodak Co Photographisches Verfahren zur Herstellung eines Mehrfarbenbildes
US3132946A (en) * 1960-01-11 1964-05-12 Eastman Kodak Co Contact screens for photogravure
US4002477A (en) * 1973-11-28 1977-01-11 Eastman Kodak Company Diffusion transfer processes and elements using or containing inert transitional metal complex oxidizing agents
JPS5096216A (enrdf_load_stackoverflow) * 1973-12-24 1975-07-31
JPS5250230A (en) * 1975-10-20 1977-04-22 Fuji Photo Film Co Ltd Method for forming color photographic image
US4284714A (en) * 1979-05-09 1981-08-18 Fuji Photo Film Co., Ltd. Method of forming a photographic image

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Publication number Publication date
FR1103430A (fr) 1955-11-03
BE527178A (enrdf_load_stackoverflow)
DE962666C (de) 1957-04-11
GB755655A (en) 1956-08-22

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