US3619155A - Photographic products and processes utilizing a polyvalent metal ion-cross-linked polymeric layer - Google Patents

Photographic products and processes utilizing a polyvalent metal ion-cross-linked polymeric layer Download PDF

Info

Publication number
US3619155A
US3619155A US42394A US3619155DA US3619155A US 3619155 A US3619155 A US 3619155A US 42394 A US42394 A US 42394A US 3619155D A US3619155D A US 3619155DA US 3619155 A US3619155 A US 3619155A
Authority
US
United States
Prior art keywords
layer
silver halide
polymeric layer
dye
polymeric
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
Application number
US42394A
Other languages
English (en)
Inventor
Richard W Young
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Polaroid Corp
Original Assignee
Polaroid Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Polaroid Corp filed Critical Polaroid Corp
Application granted granted Critical
Publication of US3619155A publication Critical patent/US3619155A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

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
    • G03C8/00—Diffusion transfer processes or agents therefor; Photosensitive materials for such processes
    • G03C8/42—Structural details
    • G03C8/52—Bases or auxiliary layers; Substances therefor
    • 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
    • G03C8/00—Diffusion transfer processes or agents therefor; Photosensitive materials for such processes

Definitions

  • ⁇ llom POLYMERIC LAVER was: RECEIVING LAYER rnmsmrzur uvzn ABSTRACT: A photographic film unit adapted to be processed by passing said unit between a pair of juxtaposed pressure-applying members which includes a composite structure composed of a plurality of layers including a photosensitive silver halide emulsion layer having associated therewith a dye image-forming material which is processing composition soluble and difi'usible as a function of exposure of the photosensitive silver halide emulsion layer to incident actinic radiation; a polymeric layer dyeable by said dye image-forming material; opacifying means adapted to be interposed intermediate the dyeable polymeric layer and next adjacent silver halide emulsion layer and associated dye image-forming material in a quantity adapted to mask dye image-forming material in a quantity adapted to mask dye image-fonning material associated with the silver halide emulsion layer subsequent to photoexposure of the emulsion; a substantially continuous polymeric
  • the present invention relates to photography and, more particularly, to photographic products particularly adapted for employment in photographic diffusion transfer color processes.
  • the primary objects of the present invention are to provide photographic products particularly adapted for employment in diffusion transfer color processes; to provide photographic products which comprise a photosensitive composite structure which contains a plurality of essential layers including a first dimensionally stable, liquid impermeable layer, photosensitive silver halide emulsion layer having a dye image-forming material associated therewith which is soluble and diffusible in processing composition as a function of the point-to-point degree of exposure of its associateed silver halide emulsion layer, a polymeric layer dyeable by the dye image-forming material, and a second dimensionally stable, liquid impermeable layer, transparent to incident radiation, a substantially continuous polymeric layer having metal ions associated therewith adapted to be interposed intermediate the dyeable polymeric layer and next adjacent silver halide emulsion layer subsequent to substantial dye image formation in the dyeable polymeric layer, in combination with a rupturable container retaining a processing composition fixedly positioned and extending transverse a leading edge of the composite photosensitive structure whereby to effect, upon application of
  • the invention accordingly comprises the product possessing the features, properties and the relation of components and the process involving the several steps and the relation and order of one or more of such steps with respect to each of the others which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.
  • FIG. 1 is a perspective view of a photographic film unit embodying the invention
  • FIGS. 2, 4 and 6 are diagrammatic enlarged cross-sectional views of the film unit of FIG. I, along section line 2-2, illustrating the association of elements during the three illustrated stages of the performance of a diffusion transfer process, for the production of a multicolor transfer image according to the invention, the thickness of the various materials being exaggerated, and wherein FIG. 2 represents an exposure stage, FIG. 4 represents a processing stage and FIG. 6 represents a product of the process;
  • FIGS. 3, and 7 are diagrammatic, further enlarged crosssectional views of the film unit of FIGS. 2, 4 and 6, along section lines 3--3, 5-5 and 7-7, respectively, further illustrating, in detail, the arrangement of layers comprising the photosensitive laminate during the three illustrated stages of the transfer process;
  • FIGS. 8 and 9 illustrate comparative spectral densities between a control and a film unit of the present invention.
  • a photosensitive element containing a dye developer that is, a dye which is a silver halide developing agent, and a silver halide emulsion may be exposed and wetted by a liquid processing composition, for example, by immersion, coating, spraying, flowing, etc., in the dark, and the exposed photosensitive element superposed prior to, during, or after wetting, on a sheetlike support element which may be utilized as an image-receiving element.
  • the liquid processing composition is applied to the photosensitive element in a substantially uniform layer as the photosensitive element is brought into superposed relationship with the image-receiving layer.
  • the liquid processing composition positioned intermediate the photosensitive element and the image-receiving layer, permeates the emulsion to initiate development of the latent image contained therein.
  • the dye developer is immobilized or precipitated in exposed areas as a consequence of the development of the latent image. This immobilization is apparently, at least in part, due to a change in the solubility characteristics of the dye developer upon oxidation and especially as regards its solubility in alkaline solutions. It may also be due in part to a tanning effect on the emulsion by oxidized developing agent, and in part to a localized exhaustion of alkali as a result of development.
  • the dye developer is unrelated and diffusible and thus provides an imagewise distribution of unoxidized dye developer dissolved in the liquid processing composition, as a function of the point-to-point degree of exposure of the silver halide emul' sion. At least part of this imagewise distribution of unoxidized dye developer is transferred, by imbibition, to a superposed image-receiving layer or element, said transfer substantially excluding oxidized dye developer.
  • the image-receiving element receives a depthwise diffusion, from the developed emulsion, of unoxidized dye developer without appreciably disturbing the imagewise distribution thereof to provide the reversed or positive color image of the developed image.
  • the image-receiving element may contain agents adapted to mordant or otherwise fix the diffused, unoxidized dye developer.
  • the desired positive image is revealed by stripping the imagereceiving layer from the photosensitive element at the end of a suitable imbibition period.
  • the dye developers are compounds which contain, in the same molecule, both the chromophoric system of a dye and also a silver halide developing function.
  • a silver halide developing function is meant a grouping adapted to develop exposed silver halide.
  • a preferred silver halide development function is a hydroquinonyl group.
  • Other suitable developing functions include ortho-dihydroxyphenyl and orthoand para-amino substituted hydroxyphenyl groups.
  • the development function includes a benzenoid developing function, that is, an aromatic developing group which forms quinonoid or quinone substances when oxidized.
  • Multicolor images may be obtained using color image-forming components such as, for example, the previously mentioned dye developers, in diffusion transfer processes by several techniques.
  • One such technique contemplates obtain ing multicolor transfer images utilizing dye developers by em ployment of an integral multilayer photosensitive element, such as is disclosed in the aforementioned US. Pat. No. 2,983,606, and particularly with reference to FIG. 9 of the patents drawing wherein at least two selectively sensitized photosensitive strata, superposed on a single support, are processed, simultaneously and without separation, with a single, common imagereceiving layer.
  • a suitable arrangement of this type comprises a support carrying a red-sensitive silver halide emulsion stratum, a green-sensitive silver halide emulsion stratum and a blue-sensitive silver halide emulsion stratum, said emulsions having associated therewith, respectively, for example, a cyan dye developer, a magenta dye developer and a yellow dye developer.
  • the dye developer may be utilized in the silver halide emulsion layer, for example, in the form of particles, or it may be employed as a layer behind the appropriate silver halide emulsion strata.
  • Each set of silver halide emulsion and associated dye developer strata are disclosed to be optionally separated from other sets by suitable interlayers, for example, by a layer of gelatin or polyvinyl alcohol.
  • suitable interlayers for example, by a layer of gelatin or polyvinyl alcohol.
  • a yellow dye developer of the appropriate spectral characteristics and present in a state capable of func tioning as a yellow filter may be employed. In such instances, a separate yellow filter may be omitted.
  • the dye developers are preferably selected for their ability to provide colors that are useful in carrying out subtractive color photography, that is, the previously mentioned cyan, magenta and yellow.
  • the dye developers employed may be incorporated in the respective silver halide emulsion or, in the preferred embodiment, in a separate layer behind the respective silver halide emulsion.
  • the dye developer may, for example, be in a coating or layer behind the respective silver halide emulsion and such a layer of dye developer may be applied by use of a coating solution containing about 0.5 to 8 percent, by weight, of the respective dye developer distributed in a film-forming natural, or synthetic, polymer, for example, gelatin, polyvinylalcohol, and the like, adapted to be permeated by the chosen diffusion transfer fluid processing composition.
  • a coating solution containing about 0.5 to 8 percent, by weight, of the respective dye developer distributed in a film-forming natural, or synthetic, polymer, for example, gelatin, polyvinylalcohol, and the like, adapted to be permeated by the chosen diffusion transfer fluid processing composition.
  • solution dyeable polymers such as nylon as, for example, N-methoxymethyl polyhexamethylene adipamide; partially hydrolyzed polyvinyl acetate; polyvinyl alcohol with or without plasticizers; cellulose acetate with filler as, for example, one-half cellulose acetate and one-half oleic acid; gelatin; and other materials of a similar nature.
  • Preferred materials comprise polyvinyl alcohol or gelatin containing a dye mordant such as poly-4-vinylpyridine, as disclosed in US. Pat. No. 3,148,061, issued Sept. 8, 1964.
  • the liquid processing composition referred to for effecting multicolor diffusion transfer processes comprises an aqueous solution of an alkaline material, for example, diethylamine, sodium hydroxide or sodium carbonate and the like, and preferably possessing a pH in excess of 12, and most preferably includes a viscosity-increasing compound constituting a film-fonning material of the type which, when the composition is spread and dried, forms a relatively firm and relatively stable film.
  • the film-forming materials disclosed comprise high molecular weight polymers such as polymeric, water-soluble ethers which are inert to an alkaline solution such as, for example, a hydroxyethyl cellulose or sodium carboxymethyl cellulose.
  • film-forming materials or thickening agents whose ability to increase viscosity is substantially unaffected if left in solution for a long period of time are also disclosed to be capable of utilization.
  • the film-forming material is preferably contained in the processing composition in such suitable quantities as to impart to the composition a viscosity in excess of I cps. at a temperature of approximately 24 C. and preferably in the order of 100,000 cps. to 200,000 cps. at that temperature.
  • an image-receiving layer of the type disclosed in that patent need not be separated from its superposed contact with the photosensitive element, subsequent to transfer image formation, if the image-receiving element is transparent and a processing composition containing a substance rendering the processing composition layer opaque is spread between the image-receiving layer and the silver halide emulsion or emulsrons.
  • the transfer image thus formed is unstable over an extended period of time.
  • the dye image instability is due, at least in part of the presence of what is, in general, a relatively high pH alkaline composition in intimate contact with the dye or dyes forming the image. This contact itself provides instability to the molecular structure of dye by, for example, catalyzing degradation and undesirable structural shifts effecting the spectral absorption characteristics of the image dye.
  • an alkaline composition possessing a pH at which the dye, for example, in reduced form, diffuses
  • an integral dynamic system wherein oxidized dye, immobilized in areas of the photosensitive element, as a function of its development, with the passage of time attempts to generate, in such areas, an equilibrium between oxidized and reduced dye.
  • the pH of the dynamic system is such that diffusion of the reduced form of the dye will occur, such reduced dye will, at least in part, transfer to the image-receiving layer and the resultant diffusion will imbalance the equilibrium, in such areas of the photosensitive element, in favor of additional formation of reduced dye.
  • an integral photographic film unit particularly adapted for the production of a dye transfer image of unexpectedly improved stability and other properties, by a color diffusion transfer process will be constructed, for example, in accordance with aforementioned US. Pat. No. 3,415,644, to include a photosensitive element comprising a laminate having, in sequence, as essential layers, a dimensionally stable opaque layer; a photosensitive silver halide emulsion layer having associated therewith dye image-providing material which is soluble and diffusible, in alkali, at a first pH; an alkaline solution permeable polymeric layer dyeable by the dye image-providing material; a polymeric acid layer containing sufficient acidifying groups to effect reduction, subsequent to substantial transfer dye image formation, of a selected processing solution having the first pH to a second pH at which said dye image-providing material is insoluble and nondiffusible; and a dimensionally stable transparent layer.
  • a rupturable container retaining an aqueous alkaline processing composition having the first pH and containing an opacifying agent, in a quantity sufficient to mask the dye image-providing material, is fixedly positioned and extends transverse a leading edge of the laminate whereby to effect unidirectional discharge of the containers contents between the alkaline solution permeable and dyeable polymeric layer and the photosensitive silver halide emulsion layer next adjacent thereto, upon application of compressive force to the container.
  • the dimensionally stable polymeric support layer next adjacent the photosensitive silver halide emulsion layer or layers may be transparent, as disclosed in aforementioned U.S. Pat. No, 3,415,646, and that in such instance the opacifying agent may be initially dispersed in the composite film unit intermediate the dyeable polymeric layer and the silver halide emulsion layer next ad'- jacent, as disclosed in aforementioned U.S. Pat. No. 3,415,645.
  • film units fabricated in accordance with the parameters set forth above specifically require the presence of the stated neutralizing component to effect in situ process adjustment of the film units operational pH range.
  • the film units require the presence of a polymeric neutralizing layer such as, for example, of the type set forth in US. Pat. No. 3,362,819 which, most preferably, includes the presence of an inert timing or spacer layer intermediate the polymeric layer carried on a support and the image-receiving layer.
  • a polymeric neutralizing layer such as, for example, of the type set forth in US. Pat. No. 3,362,819 which, most preferably, includes the presence of an inert timing or spacer layer intermediate the polymeric layer carried on a support and the image-receiving layer.
  • the polymeric neutralizing layer may comprise polymers which contain acid groups, such as carboxylic acid and sulfonic acid groups, where are capable of forming salts with alkali metals, such as sodium, potassium etc., or with organic bases, particularly quaternary ammonium bases, such as tetramethyl ammonium hydroxide, or potentially acid-yielding groups, such as anhydrides or lactones, or other groups which are capable of reacting with bases to capture and retain them.
  • the acidreacting group is, of course, nondiffusible from the acid polymer layer.
  • the acid polymer contains free carboxyl groups and the transfer processing composition employed contains a large concentration of sodium and/or potassium ions.
  • the acid polymers stated to be most useful are characterized by containing free carboxyl groups, being insoluble in water in the free acid form, and by forming water-soluble sodium and/or potassium salts.
  • dibasic acid half-ester derivatives of cellulose which derivatives contain free carboxyl groups, e.g., cellulose acetate hydrogen phthalate, cellulose acetate hydrogen glutarate, cellulose acetate hydrogen succinate, ethyl cellulose hydrogen succinate, ethyl cellulose acetate hydrogen succinate, cellulose acetate hydrogen succinate hydrogen phthalate; ether and ester derivatives or cellulose modified with sulfoanhydrides, e.g., with ortho-sulfobenzoic anhydride; polystyrene sulfonic acid; carboxymethyl cellulose; polyvinyl hydrogen phthalate; polyvinyl acetate hydrogen phthalate; polyacrylic acid; acetals of polyvinyl alcohol with carboxy or sulfo substituted aldehydes, e.g., o-, m-, or p-benzaldehyde sulf
  • the pH of the processing composition preferably is of the order of at least 12 to 14.
  • the acid layer is disclosed to contain at least sufficient acid groups to effect a reduction in the pH of the image layer from a pH of about 12 to 14 to a pH of at least 11 or lower at the end of the imbibition period, and preferably to a pH of about 5 to 8 within a short time after imbibition, thus requiring, of course, that the action of the acid be accurately so controlled as not to interfere with either development of the negative or image transfer of unoxidized dye developers.
  • the pH of the image layer must be kept at a functional transfer level, for example, l2 to 14 until the dye image has been formed after which the pH is reduced very rapidly to a pH below that at which dye transfer may be accomplished, for example, at least about 11 and preferably about pH 9 to 10.
  • Unoxidized dye developers containing hydroquinonyl developing radicals diffuse from the negative to the positive as the sodium or other alkali salt.
  • the difi'usion rate of such dye image-forming components thus is at least partly a function of the alkali concentration, and it is necessary that the pH of the image layer remain on the order of, for example, 12 to 14 until transfer of the necessary quantity of dye has been accomplished.
  • the subsequent pH reduction in addition to its desirable effect upon image light stability, serves a highly valuable photographic function by substantially terminating further dye transfer.
  • the acid groups are disclosed to be so distributed in the acid polymer layer that the rate of their availability to the alkali is controllable, e.g., as a function of the rate of swelling of the polymer layer which rate in turn has a direct relationship to the diffusion rate of the alkali ions.
  • the desired distribution of the acid groups in the acid polymer layer may be effected by mixing the acid polymer with a polymer free of acid groups, or lower in concentration of acid groups, and compatible therewith, or by using only the acid polymer but selecting one having a relatively lower proportion of acid groups.
  • the layer containing the polymeric acid may contain a water-insoluble polymer, preferably a cellulose ester, which acts to control or modulate the rate at which the alkali salt of the polymer acid is formed.
  • a water-insoluble polymer preferably a cellulose ester
  • cellulose esters contemplated for use mention is made of cellulose acetate, cellulose acetate butyrate, etc.
  • the particular polymers and combinations of polymers employed in any given embodiment are, of course, selected so as to have adequate wet and dry strength and when necessary or desirable, suitable subcoats are employed to help the various polymeric layers adhere to each other during storage and use.
  • the inert spacer layer of the last-mentioned patent acts to time control the pH reduction by the polymeric acid layer. This timing is disclosed to be a function of the rate at which the alkali diffuses through the inert spacer layer. It is there stated to have been found that the pH does not drop until the alkali has passed through the spacer layer, i.e., the pH is not reduced to any significant extent by the mere diffusion into the interlayer, but the pH drops quite rapidly once the alkali difiuses through the spacer layer.
  • an integral photographic film unit of simplified construction and particularly adapted for the production of dye transfer images of unexpectedly improved stability and other desirable properties by a color diffusion transfer process will be constructed to include a photosensitive element comprising a composite structure possessing, in sequence, as essential layers, a first dimensionally stable layer, a photosensitive silver halide emulsion layer having associated therewith a dye image-fonning material which is soluble and diffusible as a function of the point-to-point degree of emulsion photoexposure, a polymeric layer dyeable by the dye image-forming material, and a second dimensionally stable layer transparent to incident actinic radiation.
  • a photosensitive element comprising a composite structure possessing, in sequence, as essential layers, a first dimensionally stable layer, a photosensitive silver halide emulsion layer having associated therewith a dye image-fonning material which is soluble and diffusible as a function of the point-to-point degree of emulsion photoexposure, a polymeric layer dyeable by the dye
  • a rupturable container retaining a processing composition is fixedly positioned and extends transverse a leading edge of the composite structure whereby to effect, upon application of compressive pressure, discharge of the processing composition intermediate the dyeable polymeric layer and the photosensitive silver halide emulsion and associated dye image-forming material next adjacent thereto.
  • the aforementioned integral photographic film unit possesses means for interposing between said dyeable polymeric layer and the photosensitive silver halide emulsion next adjacent thereto, a continuous, polymeric layer having metal ions associated therewith, after substantial image formation has been accomplished in said dyeable polymeric layer, in order to obviate further migration of dye or reaction products or residues of the photographic development process which are detrimental to quality and/or stability of dye transfer images.
  • Means for providing said continuous polymeric layer include disposing a substantially continuous polymeric material intermediate the dye image-forming layer and the photosensitive silver halide emulsion next adjacent thereto, said polymeric material being normally permeable to the dye image-forming material, but when associated with a metal ion provided by, for example, a metallic salt disposed in the film unit, functions to prevent further transfer of dye image-forming material or other reaction products or residues, after the dye image-forming material has completed imagewise transfer, which effect image quality by, e.g., causing stain or darkening in the image highlights or indiscriminate dye imageforrning material transfer.
  • the metal ion and polymeric material may be selected to provide, upon association, a metal ion cross-linked polymeric material substantially impermeable to at least dye image-fenning material.
  • Means for the formation of such a continuous polymeric layer specifically include, for example, providing a film-forming polymeric processing composition component such as a viscosity increasing agent and metal ion which may be directly or by means of a metal ion donor located at various positions in the photographic film unit such that after a predetermined time following the distribution of the processing composition, the metal ion component will become functionally associated with the polymeric material whereupon a barrier to the unwanted dye image-forming materials and process reaction products is formed, intermediate the dyeable polymeric layer and the next adjacent photosensitive silver halide emulsion.
  • a film-forming polymeric processing composition component such as a viscosity increasing agent and metal ion which may be directly or by means of a metal ion donor located at various positions in the photographic film unit such that after a predetermined time following the distribution of the processing composition, the metal ion component will become functionally associated with the polymeric material whereupon a barrier to the unwanted dye image-forming materials and process reaction products is formed, intermediate the dyeable polymeric
  • a normally dye image-forming material penneable polymeric layer is located as a preformed layer intermediate the dyeable polymeric layer and next adjacent photosensitive silver halide emulsion layer and a diffusible metal ion contacts with the polymeric layer preventing the transfer to the dyeable polymeric layer of undesirable materials.
  • in situ barrier formation of the present invention may be provided by initially disposing a polymeric material permeable to the dye image-forming material intermediate the dyeable polymeric layer and the next adjacent photosensitive silver halide emulsion and a metal ion donor in an element of the composite film unit and/or incorporated in the processing composition to provide during processing, subsequent to substantial dye transfer image formation, association with the polymeric material in a concentration effective to provide a barrier substantially impermeable to further dye image-forming material transfer.
  • the residue of the photographic processing reagents such as booster developer, onium compounds, etc., and the reaction products thereof, which may result in the formation of colored forms, must also be restrained from passing to the dyeable polymeric layer.
  • unwanted materials diverse in chemical constitution and molecular configuration, can be restrained by chemical and/or physical means from transferring to the dyeable polymeric layer, by employing, with a film-forming polymeric material which is normally permeable to said materials, an associated metal ion.
  • the metal ion may be disposed, for example, as a metallic salt, in the processing composition; in permeable layers adjacent to the photosensitive silver halide emulsion layers; in permeable layers adjacent the dyeable polymeric layer; in the photosensitive silver halide emulsion layers or in the dyeable polymeric layer, or the like.
  • the specific time delay from the start of dye image-forming material transfer until the permeability of the polymeric material is decreased to such a degree that the dye image-forming material is incapable of passing therethrough is determined by the predetermined time necessary for the metal ion to diffuse into contact with the polymeric material and/or by employing a pH-controlled system wherein the metal ion will not be functionally available at a preselected first pH, but as the pH of the system is converted during processing to a preselected second pH, effective metal ion contact is generated and the modulation-of the system increases to a point where the dye image-fonning material and other unwanted materials are incapable of deleterious transfer to the dyeable polymeric layer.
  • the barrier is formed by employing a film-fonning polymeric component, for example, a viscosity-increasing component, of the processing composition to provide the requisite polymeric layer in situ during processing of the film unit.
  • a film-fonning polymeric component for example, a viscosity-increasing component
  • carboxymethyl hydroxyethyl cellulose and carboxymethyl cellulose are commonly employed as viscosity-increasing agents in difiusion transfer processes as more fully disclosed and discussed in numerous of the aforementioned patents and particularly in US. Pat. No. 2,983,606.
  • the metal ion for example, derived from a processing composition ionizable metallic salt donor, may be disposed in the various above-indicated locations conveniently since the metal ion and the specified polymers are stable and nonreactive to each other in each other's absence and/or while the pH of the system comprises a preselected insulating environment and the barrier formation mechanism occurs at preselected pH generated during processing of the film unit.
  • excess alkaline material may be provided to the processing composition to minimize or obviate the effect of such initial pH lowering.
  • the present invention contemplates the employment of combinations of metal ions as well as a single metal ion and combinations of polymers.
  • the most favorable properties of each of the materials can be employed in a film structure to achieve the greatest degree of efficiency in barrier formation and to tailor the speed and manner of ban'ier formation as well as the type and location of barrier formed.
  • cadmium acetate is initially disposed in the dyeable polymeric layer and nickel ion is disposed in the processing composition as nickel carbonate with carboxymethyl cellulose.
  • the pH of the system drops from an initial first pH to a second pH the cadmium and nickel cations become available to the system, thus forming the barrier to the transfer of dye image-forming materials and other undesirable materials to the dyeable polymer.
  • suitable cations for use in the practice of the present invention, mention may be made of polyvalent metal cations, such as cadmium, calcium, magnesium, zinc, barium and nickel, preferably trivalent and tetravalent metal cations such as zirconium, aluminum and chromium.
  • polyvalent metal cations such as cadmium, calcium, magnesium, zinc, barium and nickel, preferably trivalent and tetravalent metal cations such as zirconium, aluminum and chromium.
  • the more preferred cations are those with the higher valence.
  • the particular anion selected where one or more metallic salts are utilized is not critical; it is only required that the salt be soluble in the processing composition to produce the required metal ion species under the desired pH conditions and be compatible with the particular environment in which it is disposed in the composite film structure and be photographically acceptable, that is, produce no deleterious effects on the photographic capability of the film unit.
  • Preferred anions include the acetate, nitrate and carbonate.
  • the specific salt selected, or alternatively, chelated metal cation, as indicated above, will be determined by the operator depending upon the location of the salt in the film unit, as well as the desired time and location of the barrier formation.
  • the filmfonning polymeric layer is composed of approximately 90 percent carboxymethyl cellulose and percent hydroxyethyl cellulose and the metal ion is zirconium.
  • a precast layer of polymeric material not cast from the processing composition it is preferred that such layer be located intermediate the dyeable layer and the silver halide emulsion layer next adjacent thereto at a position more distal from the image-receptive layer than the processing composition is to occupy.
  • the amount of polymeric materials and metal ion utilized to form the herein denoted barrier layers will be determined empirically since various materials will provided different barrier effects for given concentrations. It has been found that, as a rule, a sufficient concentration of polymeric material to provide a continuous layer possessing a thickness of approximately 20 microns will suffice to provide the designated functionality to the system.
  • the substantially continuous layer may contain entrained or entrapped therein one or more of the components, adjuvants or agents originally retained by the processing composition or the like, such as opacifying agent initially distributed in the processing composition in the preferred film unit embodiments detailed hereinabove.
  • the substantially continuous polymeric film provided within one or more of the embodiments denoted herein, in addition to being impermeable to excess solubilized dye image-forming materials will also be substantially impenneable to solubilized photographic adjuncts present in the film unit in general and more particularly those possessing physical dimensions as, for example, molecular size, less than that of dye developer such as, for example, antifoggants, development restrainers, quaternary accelerators, emulsion stabilizers and sensitizers and the like, and reaction products thereof, in order to still further enhance maintenance of dye transfer image stability and acuity.
  • dye developer such as, for example, antifoggants, development restrainers, quaternary accelerators, emulsion stabilizers and sensitizers and the like, and reaction products thereof, in order to still further enhance maintenance of dye transfer image stability and acuity.
  • both dimensionally stable layers may be transparent and in such instance, an opacifying agent may be initially dispersed intermediate the dyeable polymeric layer and the next adjacent silver halide emulsion layer, in a quantity sufficient to mask the dye image-forming material, such opacifying agent will preferably be disposed within the processing composition, in a quantity sufficient to mask the dye imageforming material upon distribution of the processing composition intermediate the last-stated layers, and, most preferably, the dimensionally stable layer next adjacent the photosensitive silver halide emulsion layer will be opaque with respect to externally derived incident actinic radiation.
  • the preferred dye image-providing materials comprise dyes which are silver halide developing agents, as stated above, for purposes of simplicity and clarity, the present invention is described hereinafter in terms of such dyes, without limitation of the invention to the illustrative dyes denoted, and, in addition, the photographic film unit structure will be detailed hereinafter employing the last-mentioned preferred structural embodiment, without limitation of the invention to the preferred structure denoted.
  • the film unit is specifically adapted to provide for the production of a multicolor dye transfer image and the photosensitive laminate comprises, in orderof essential layers, the dimensionally stable opaque layer; at least two selectively sensitized silver halide emulsion strata each having dye image-providing materials of predetermined color associated therewith which are soluble and difi'usible in alkaline processing composition as a function of the point-to-point degree of exposure of the respective associated silver halide emulsion strata; an alkaline solution permeable polymeric layer dyeable by the dye imageproviding materials; and the dimensionally stable transparent layer.
  • the silver halide emulsions comprising the multicolor photosensitive laminate preferably possess predominant spectral sensitivity to separate regions of the spectrum and each has associated therewith a dye, which is a silver halide developing agent and is, most preferably, substantially soluble in the reduced form only at a selected pH posseming sub- I sequent to processing a spectral absorption range substantially complementary to the predominant sensitivity range of its associated emulsion.
  • a dye which is a silver halide developing agent and is, most preferably, substantially soluble in the reduced form only at a selected pH posseming sub- I sequent to processing a spectral absorption range substantially complementary to the predominant sensitivity range of its associated emulsion.
  • each of the emulsion strata, and its associated dye is separated from the remaining emulsion strata, and their associated dye, by separate alkaline solution permeable polymeric interlayers.
  • the silver halide emulsion comprises photosensitive silver halide dispersed in gelatin and is about 0.6 to 6 microns in thickness; the dye itself is dispersed in an aqueous alkaline solution polymeric binder, preferably gelatin, as a separate layer about 1 to 7 microns in thickness; the alkaline solution permeable polymeric interlayers, preferably gelatin, are about 1 to 5 microns in thickness; the alkaline solution dyeable polymeric layer is transparent and about 0.25 to 0.4 mil. in thickness; and each of the dimensionally stable opaque and transparent layers are alkaline solution impermeable and about 2 to 6 mils. in thickness.
  • the relative dimensions recited above may be appropriately modified, in accordance with the desires of the operator, with respect to the specific product to be ultimately prepared.
  • the respective silver halide/dye developer units of the photosensitive element will be in the form of a tripack configuration which will ordinarily comprise a cyan dye developer/red-sensitive emulsion unit contiguous the dimensionally stable opaque layer, the yellow dye developer/blue-sensitive emulsion unit most distant from the opaque layer and the magenta dye developer/green-sensitive emulsion unit intermediate those units, recognizing that the relative order of such units may be varied in accordance with the desires of the operator.
  • FIGS. 1 through 7 of the drawings wherein there is illustrated a preferred film unit of the present invention and wherein like numbers, appearing in the various figures, refer to like components.
  • FIG. 1 sets forth a perspective view of the film unit, designated 10, and each of FIGS. 2 through 7 illustrate diagrammatic cross-sectional views of film unit 10, along the stated section lines 2--2, 33, 5-5 and 7-7, during the various depicted stages in the performance of a photographic diffusion transfer process as detailed hereinafter.
  • Film unit 10 comprises rupturable container 11, retaining, prior to processing, aqueous alkaline solution 12, and photosensitive laminate 13 including, in order, dimensionally stable opaque layer 14, preferably an actinic radiation-opaque flexible sheet material; cyan dye developer layer 15; red-sensitive silver halide emulsion layer 16; interlayer 17; magenta dye developer layer 18; green-sensitive silver halide emulsion later 19; interlayer 20; yellow dye developer layer 21; blue-sensitive silver halide emulsion layer 22; auxiliary layer 23, which may contain an auxiliary silver halide developing agent; imagereceiving layer 24; and dimensionally stable transparent layer 27, preferably an actinic radiation transmissive flexible sheet material.
  • opaque layer 14 preferably an actinic radiation-opaque flexible sheet material
  • cyan dye developer layer 15 red-sensitive silver halide emulsion layer 16; interlayer 17; magenta dye developer layer 18; green-sensitive silver halide emulsion later 19; interlayer 20; yellow dye developer layer 21
  • the structural integrity of laminate 13 may be maintained, at least in part, by the adhesive capacity exhibited between the various layers comprising the laminate at their opposed surfaces.
  • the adhesive capacity exhibited at an interface intermediate image-receiving layer 24 and the silver halide emulsion layer next adjacent thereto, for example, intermediate image-receiving layer 24 and auxiliary layer 23 as illustrated in FIGS. 2 through 7, should be less than that exhibited at the interface between the opposed surfaces of the remainder of the layers forming the laminate, in order to facilitate distribution of processing solution 12 intermediate the stated image-receiving layer 24 and the silver halide emulsion layer next adjacent thereto.
  • the laminates structural integrity may also be enhanced or provided, in whole or in part, by providing a binding member extending around, for example, the edges of laminate l3, and maintainingthe layers comprising the laminate intact, except at the interface between layers 23 and 24 during distribution of alkaline solution 12 intermediate those layers.
  • the binding member may comprise a pressure-sensitive tape 28 securing and or maintaining the layers of laminate 13 together at its respective edges. Tape 28 will also act to maintain processing solution 12 intermediate image-receiving layer 24 and the silver halide emulsion layer next adjacent hereto, upon application of compressive pressure to pod l1 and distribution of its contents intermediate the stated layers. Under such circumstances, binder tape 28 will act to prevent leakage of fluid processing composition from the film unit's laminate during and subsequent to photographic processing.
  • Rupturable container ill may be of the type shown and described in any of U.S. Pat. Nos. 2,543,18l; 2,634,886; 2,653,732; 2,723,051; 3,056,492; 3,056,49l; 3,l52,5l5; and the like.
  • such containers will comprise a rectangular blank of fluidand air-impervious sheet material folded longitudinally upon itself to form two walls 29 which are sealed to one another along their longitudinal and end margins to form a cavity in which processing solution 12 is retained.
  • the longitudinal marginal seal 30 is made weaker than the end seals 31 so as to become unsealed in response to the hydraulic pressure generated within the fluid contents 12 of the container by the application of compressive pressure to walls 29 of the container.
  • container 1! is fixedly positioned and extends transverse a leading edge of photosensitive laminate 13 whereby to effect unidirectional discharge of the containers contents 112 between image-receiving layer 24 and the stated layer next adjacent thereto, upon application of compressive force to container 11.
  • container 11 as illustrated in FIG. 2, is fixedly positioned and extends transverse a leading edge of laminate 13 with its longitudinal marginal seal 30 directed toward the interface between imagereceiving layer 24 and auxiliary layer 23.
  • FIGS. 1 is fixedly positioned and extends transverse a leading edge of photosensitive laminate 13 whereby to effect unidirectional discharge of the containers contents 112 between image-receiving layer 24 and the stated layer next adjacent thereto, upon application of compressive force to container 11.
  • container 11 as illustrated in FIG. 2
  • container 11 is fixedly positioned and extends transverse a leading edge of laminate 13 with its longitudinal marginal seal 30 directed toward the interface between imagereceiving layer 24 and auxiliary layer 23.
  • container 11 is fixedly secured to laminate 13 by extension 32 of tape 28 extending over a portion of one wall 29 of the container, in combination with a separate retaining member such as illustrated retaining tape 33 extending over a portion of the other wall 29 of the container and a portion of laminate 13's surface generally equal in area to about that covered by tape 28.
  • extension flap 32 of tape 28 is preferably of such area and dimensions that upon, for example, manual separation of container 11 and tape 33, sub sequent to distribution of processing composition 12, from the remainder of film unit 10, flap 32 may be folded over the edge of laminate 13, previously covered by tape 33, in order to facilitate maintenance of the laminate's structural integrity, for example, during the flexations inevitable in storage and use of the processed film unit, and to provide a suitable mask or frame, for viewing of the transfer image through the picture viewing area of transparent layer 27.
  • the fluid contents of the container comprise an aqueous alkaline solution, having a pH and solvent concentration at which the dye developers are soluble and diffusible, which contains an opacifying agent in a quantity sufficient to mask the dye developers associated with the silver halide emulsions subsequent to processing and optionally contains a polymeric material adapted upon contact with a metal ion cross-linking agent therefor to provide a substantially continuous, dye impermeable polymeric layer.
  • the concentration of opacifying agent or agents selected will be that sufficient to prevent further exposure of the film unit's silver halide emulsion or emulsions, by actinic radiation transversing through the dimensionally stable transparent layer, subsequent to distribution of the processing solution intennediate the dyeable polymeric layer and the stated layer next adjacent thereto.
  • the film unit may be processed, subsequent to distribution of the composition, in the presence of such radiation, in view of the fact that the silver halide emulsion or emulsions of the laminate are appropriately protected by incident radiation, at one major surface by the opaque processing composition and at the remaining major surface by the dimensionally stable opaque layer.
  • the selected opacifying agent should beone providing a background suitable for viewing the dye developer transfer image formed in the dyeable polymeric layer.
  • an opacifying agent be selected that will not in terfere with the color integrity of the dye transfer image, as viewed by the observer, and, most preferably, an agent which is aesthetically pleasing to the viewer and does not provide a background noise signal degrading, or detracting from, the information content of the image.
  • Particularly desirable opacifying agents will be those providing a white background, for viewing the transfer image, and specifically those conventionally employed to provide background for reflection photographic prints and, especially, those agents possessing the optical properties desired for reflection of incident radiation.
  • opacifying agents examples include barium sulfate, zinc oxide, titanium oxide, barium stearate, silver flake, silicates, alumina, zirconium oxide, zirconium acetyl acetate, sodium zirconium sulfate, kaoline, mica, and the like.
  • a particularly preferred agent comprises titanium dioxide due to its highly effective reflection properties.
  • a processing composition containing about 40-70 grams of titanium dioxide dispersed in 100 cc. of water will provide a percent reflectance of about 85-90 percent.
  • the percent reflectance particularly desired will be in the order of above 85 percent.
  • a processing composition containing, for example, titanium dioxide or the like, selected predominantly for its radiation reflecting properties, beyond that ordinarily obtained or required to obscure or mask the dye and/or developed silver associated with the photosensitive silver halide emulsion layers
  • an additional opacifying agent exhibiting more effective filtration of radiation incident on the transparent support layer during processing, such as carbon black, for example, added in a concentration of about one part carbon black to 100 to 500 parts titanium dioxide, in order to further protect the emulsions from physical fog formation during processing.
  • the unit In the performance of a diffusion transfer multicolor process employing film unit 10, the unit is exposed to radiation, actinic to photosensitive laminate l3, incident on the laminate's exposure surface 34, as illustrated in FIG. 2.
  • film unit is processed by being passed through opposed suitable gapped rolls 35 in order to apply compressive pressure to frangible container 11 and to effect rupture of longitudinal seal 30 and distribution of alkaline processing composition 12, having a pH and solvent concentration at which the cyan, magenta and yellow dye developers are soluble and diffusible and containing film-forming polymer in a concentration suffrcient to provide substantially continuous polymeric layer subsequent to distribution, intermediate dyeable polymeric layer 24 and auxiliary layer 23.
  • Alkaline processing solution 12 permeates emulsion layers l6, l9 and 22 to initiate development of the latent images contained in the respective emulsions.
  • the cyan, magenta and yellow dye developers, of layers l5, l8 and 21, are immobilized, as a function of the development of their respective associated silver halide emulsions, preferably substantially as a result of their conversion from the reduced form to their relatively insoluble and nondiffusible oxidized form, thereby providing imagewise distributions of mobile, soluble and difiusible cyan, magenta and yellow dye developer, as a function of the pointto-point degree of their associated emulsions exposure.
  • At least part of the imagewise distributions of mobile cyan, magenta and yellow dye developer transfers, by diffusion, to aqueous alkaline solution permeable polymeric layer 24 to provide a multicolor dye transfer image to that layer.
  • a sufficient portion of a metallic salt contained, for example, in imagercceiving layer 24, is solubilized by contact with alkaline solution 12 whereby the metal cation of the metallic salt diffuses into contact with the polymeric layer provided as a function of distribution of processing solution 12, intermediate dyeable polymeric layer 24 and auxiliary layer 25, which is normally permeable to dye developer, providing thereby a substantially continuous dye developer impermeable polymeric layer 25 to provide thereby a stable multicolor dye transfer image.
  • container lll may be manually dissociated from the remainder of the film unit, as described above, to provide the product illustrated in FIG. 6.
  • Film units similar to that shown in the drawings may be prepared, for example, by coating, in succession, on a gelatin subbed, 4-mile opaque polyethylene terephthalate film base, the following layers:
  • a transparent 4-mil. polyethylene terephthalate film base may be coated, in succession, with the following illustrative layers:
  • the two components thus prepared may then be taped together in laminate form, at their respective edges, by means of a pressure-sensitive binding tape extending around, in contact with, and over the edges of the resultant laminate.
  • a rupturable container comprising an outer layer of lead foil and an inner liner or layer of polyvinyl chloride retaining an aqueous alkaline processing solution comprising:
  • a second photosensitive composite film structure identical to the above-described structure may be prepared except that the described polyacrylamide/polyvinyl alcohol graft copolymer layer additionally contains cadmium acetate at a coverage of 690 mgs./ft.*.
  • the photosensitive laminates may then be exposed through step wedges to selectively filtered radiation incident on the transparent polyethylene terephthalate layer and initially processed, in the absence of actinic radiation, by passage of the exposed film unit through suitable gapped opposed rolls, to efiect rupture of the container and distribution of its contents.
  • the multicolor dye transfer image formation may be viewed through the transparent polyethylene terephthalate film base.
  • a control and a test film unit containing a metallic salt cross-linking agent prepared substantially as described above were examined spectrophotometrically and the spectral densities are reproduced in FIGS. 8 and 9 with the dashed lines denoting stain which represents undesirable image-forming material present in the image layer.
  • the pH and solvent concentration of the processing solution initially employed must be a pH at which the dye developers employed are soluble and diffusible.
  • the specific pH to be employed may be readily determined empirically for any dye developer, or groups of dye developers, most particularly desirable dye developers are soluble at pHs above 9 and relatively insoluble at substantially any alkaline pH, in oxidized form, and the system can be readily balanced accordingly for such dye developers.
  • the processing composition in the preferred embodiment, will include the stated film-forming viscosity-increasing agent, or agents, to facilitate spreading of the composition and to facilitate maintenance of the spread composition as a structurally stable layer of the laminate, during distribution, it is not necessary that such agent be employed as a component of the composition.
  • a polymeric acid layer for example, of the type discussed above, may be additionally incorporated, as stated, in the film unit of the present invention, to provide reduction of the alkalinity of the processing solution from a pH at which the dyes are soluble to a pH at which the dyes are substantially nondifiusible, in order to advantageously further stabilize the dye transfer image.
  • the polymeric acid layer may be positioned intermediate the transparent support and image-receiving layer, and/or the opaque support and next adjacent emulsion/dye unit layer, and the film unit may also contain a polymeric spacer or barrier layer next adjacent the polymeric acid layer, opposite the respective support layer, as previously described.
  • the aforemen tioned rate at which the cations of the alkaline processing composition, i.e., alkali ions, are available for capture in the polymeric acid layer should be decreased with increasing transfer processing temperatures in order to provide diffusion transfer color processes relatively independent of positive transfer image variations over an extended range of ambient temperatures.
  • the diffusion rate of alkali through a permeable inert polymeric spacer layer increases with increased processing temperature to the extent, for example, that at relatively high transfer processing temperatures, that is, transfer processing temperatures above approximately F., a premature decrease in the pH of the transfer processing composition occurs due, at least in part, to the rapid ditfusion of alkali from the dye transfer environment and its subsequent neutralization upon contact with the polymeric acid layer.
  • transfer processing temperatures that is, transfer processing temperatures above approximately F.
  • the last-mentioned inert spacer layer was disclosed to provide an effective diffusion barrier timewise preventing effective traverse of the inert spacer layer by alkali having temperature depressed diffusion rates and to result in maintenance of the transfer processing environments high pH for such an extended time interval as to facilitate formation of transfer image stain and its resultant degradation of the positive transfer images color definition.
  • acetals of polyvinyl were stated to generally comprise saturated aliphatic hydrocarbon chains of a molecular weight of at least 1000, preferably of about 1000 to 50,000, possessing a degree of acetalation within about 10 to 30 percent, 10 to 30 percent, 20 to 80 percent, and 10 to 40 percent, of the polyvinyl alcohols theoretical polymeric hydroxy groups, respectively, and including mixed acetals where desired.
  • a mixture of the polymers is to be employed, for example, a mixture of hydroxypropyl methyl cellulose and partial polyvinyl butyral.
  • the stable dye transfer image is obtained irrespective of the fact that the film unit is maintained as an integral laminate unit during exposure, processing, viewing and storage of the unit, and undesired dye image-forming material transfer, of the type previously discussed in detail, subsequent to substantial dye transfer image formation, is effectively prevented by the in situ generated layer composed of filmforming polymers and metal ion. Accordingly, by means of the present invention, multicolor dye transfer images may be provided which exhibit desired maximum and minimum dye transfer image densities; yellow, magenta and cyan dye saturation; red, green and blue hues; and color separation.
  • the dimensionally stable support layers referred to may comprise any of the various types of conventional opaque and transparent rigid or flexible materials possessing the requisite liquid impermeability and vapor transmissivity denoted above, and may comprise polymeric films of both synthetic types and those derived from naturally occurring products.
  • Particularly suitable materials include aqueous alkaline solution impermeable, water vapor permeable, flexible polymeric materials such as vapor permeable polymeric films derived from ethylene glycol terephthalic acid, vinyl chloride polymers; polyvinyl acetate; polyamides; polymethacrylic acid methyl and ethyl esters; cellulose derivatives such as cellulose acetate, triacetate, nitrate, propionate, butyrate, acetatepropionate, or acetate-butyrate; alkaline solution impermeable, water vapor permeable papers; cross-linked polyvinyl alcohol; regenerated cellulose; and the like.
  • flexible polymeric materials such as vapor permeable polymeric films derived from ethylene glycol terephthalic acid, vinyl chloride polymers; polyvinyl acetate; polyamides; polymethacrylic acid methyl and ethyl esters; cellulose derivatives such as cellulose acetate, triacetate, nitrate
  • liquid processing composition employed may contain a auxiliary or accelerating developing agent, such as p-methylaminophenol, 2,4-diaminophenol, pbenzylaminophenyl, hydroquinone, toluhydroquinone, phenylhydroquinone, 4'-methylphenylhydroquinone, etc. It is also contemplated to employ a plurality of auxiliary or accelerating developing agents, such as a 3 -pyrazolidone developing agent and a benzenoid developing agent, as disclosed in U.S. Pat. No. 3,039,869, issued June 19, 1962.
  • auxiliary developing agents examples include l-phenyl-3-pyrazolidone in combination with pbenzylaminophenol and l-phenyl-3-pyrazolidone in combination with 2,5-bis-ethylenimino-hydroquinone.
  • auxiliary developing agents may be employed in the liquid processing composition or they may be initially incorporated, at least in part, in any one or more of the silver halide emulsion strata, the strata containing the dye developers, the interlayers, the overcoat layer, and the image-receiving layer, or in any other auxiliary layer, or layers, of the film unit.
  • the dye developer oxidized during development may be oxidized and immobilized as a result of a reaction, e.g., an energy-transfer action, with the oxidation product of an oxidized auxiliary developing agent, the latter developing agent being oxidized by the development of exposed silver halide.
  • a reaction e.g., an energy-transfer action
  • Such a reaction of oxidized developing agent with unoxidized dye developer would regenerate the auxiliary developing agent for further reaction with the exposed silver halide.
  • the relative proportions of the agents of the diffusion transfer processing composition may be altered to suit the requirements of the operator.
  • modify the herein described developing compositions by the substitution of preservatives, alkalies, etc., other than those specifically mentioned, provided that the pH of the composition is initially at the first pH and solvent concentration required.
  • components such as restrainers, accelerators, etc.
  • concentration of various components may be varied over a wide range and when desirable adaptable components may be disposed in the photosensitive element, prior to exposure, in a separate permeable layer of the photosensitive element, and/or in the photosensitive emulsion.
  • nitrocarboxymethyl cellulose as disclosed in U.S. Pat. No. 2,992,104
  • an acylamidobenzene sulfo ester of a partial sulfobenzal of polyvinyl alcohol as disclosed in U.S. Pat. No. 3,043,692
  • polymers of N-alkyl-a,fi-unsaturated carboxamides and copolymers of N-alky-a,B-carboxamides with N-hydroxyalkyl- B-unsaturated carboxamides as disclosed in U.S. Pat. No.
  • the preparation of the dye developer dispersion may also be obtained by dissolving the dye in an appropriate solvent, or mixture of solvents, and the resultant solution distributed in the polymeric binder, with optional subsequent removal of the solvent, or solvents, employed, as, for example, by vaporization where the selected solvent, or solvents, possesses a sufficiently low boiling point or washing where the selected solvent, or solvents, possesses a sufficiently high difierential solubility in the wash medium, for example, water, when measured against the solubility of the remaining composition components, and/or obtained by dissolving both the polymeric binder and dye in a common solvent.
  • the silver halide crystals may be prepared by reacting a water-soluble silver salt, such as silver nitrate, with at least one water-soluble halide, such as ammonium, potassium or sodium bromide, preferably together with a corresponding iodide, in an aqueous solution of a peptizing agent such as a colloidal gelatin solution; digesting the dispersion at an elevated temperature, to provide increased crystal growth; washing the resultant dispersion to remove undesirable reaction products and residual water-soluble slats by chilling the dispersion, noodling the set dispersion, and washing the noodles with cold water, or alternatively, employing any of the various flocc systems, or procedures, adapted to effect removal of undesired components, for example, the procedures described in US.
  • a water-soluble silver salt such as silver nitrate
  • water-soluble halide such as ammonium, potassium or sodium bromide
  • a peptizing agent such as a colloidal gelatin solution
  • Optical sensitization of the emulsions silver halide crystals may be accomplished by contact of the emulsion composition with an effective concentration of the selected optical sensitizing dyes dissolved in an appropriate dispersing solvent such as methanol ethanol, acetone, water, and the like; all according to the traditional procedures of the art, as described in Hammer, F. M., The Cyanine Dyes and Related Compounds.
  • an appropriate dispersing solvent such as methanol ethanol, acetone, water, and the like
  • Additional optional additives such as coating aids, hardeners, viscosity-increasing agents, stabilizers, preservatives, and the like, for example, those set forth hereinafter, also may be incorporated in the emulsion formulation, according to the conventional procedures known in the photographic emulsion manufacturing art.
  • the photoresponsive material of the photographic emulsion will, as previously described, preferably comprise a crystal of silver, for example, one or more of the silver halides such as silver chloride, silver iodide, silver bromide, or mixed silver halides such as silver chlorobromide or silver iodobromide, of varying halide ratios and varying silver concentrations.
  • the silver halides such as silver chloride, silver iodide, silver bromide, or mixed silver halides such as silver chlorobromide or silver iodobromide, of varying halide ratios and varying silver concentrations.
  • the emulsion may include the various adjuncts, or addenda, according to the techniques disclosed in the art.
  • the aforementioned gelatin may be, in whole or in part, replaced with some other colloidal material such as albumin; casein; or zein; or resins such as cellulose derivatives, as described in U.S. Pat. Nos. 2,322,085 and 2,327,808; polyacrylamides, as described in U.S. Pat. No. 2,541,474; vinyl polymers such as described in an extensive multiplicity of readily available U.S. and foreign patents.
  • the photosensitive component of the film unit may comprise at least two sets of selectively sensitized minute photosensitive elements arranged in the form of a photosensitive screen wherein each of the minute photosensitive elements has associated therewith, for example, an appropriate dye developer in or behind its respective silver halide emulsion portion.
  • a suitable photosensitive screen will comprise minute red-sensitized emulsion elements, minute green-sensitized emulsion ele ments and minute blue-sensitized emulsion elements arranged in side-by-side relationship in a screen pattern and having associated therewith, respectively, a cyan, a magenta and a yellow dye developer.
  • the present invention also includes the employment of a black dye developer and the use of a mixture of dye developers adapted to provide a black and white transfer image, for example, the employment of dye developers of the three subtractive colors in an appropriate mixture in which the quantities of the dye developers are proportioned such that the colors combine to provide black.
  • the expression positive image has been used, this expression should not be interpreted in a restrictive sense since it is used primarily for purposes of illustration, in that it defines the image produced on the imagecarrying layer as being reversed, in the positive-negative sense, with respect to the image of the photosensitive emulsion layers.
  • positive image to assume that the photosensitive element is exposed to actinic light through a negative transparency. In this case, the latent image in the photosensitive emulsion layers will be a positive and the dye image produced on the imagecarrying layer will be a negative.
  • the expression positive image is intended to cover such an image produced on the image-carrying layer.
  • the transfer image formed upon direct exposure of the film unit to a selected subject and processing will be geometrically reversed image of the subject. Accordingly, to provide transfer image formation geometrically nonreversed, exposure of such film unit should be accomplished through an image reversing optical system such as a camera possessing an image reversing optical system.
  • the film unit may also contain one or more subcoats or layers, which, in turn, may contain one or more additives such as plasticizers, intermediate essential layers for the purpose, for example, of improving adhesion, and that any one or more of the described layers may comprise a composite of two or more strata of the same, or different, components and which may be contiguous, or separated from, each other, for example, two or more neutralizing layers or the like, one of which may be disposed intermediate the cyan dye image-founing component retaining layer and the dimensionally stable opaque layer.
  • additives such as plasticizers, intermediate essential layers for the purpose, for example, of improving adhesion
  • any one or more of the described layers may comprise a composite of two or more strata of the same, or different, components and which may be contiguous, or separated from, each other, for example, two or more neutralizing layers or the like, one of which may be disposed intermediate the cyan dye image-founing component retaining layer and the dimensionally stable opaque layer.
  • a photographic film unit which comprises, in combination:
  • a photosensitive element comprising a composite structure containing, as essential layers, in sequence, a first dimensionally stable layer opaque to incident actinic radiation; a photosensitive silver halide emulsion layer having associated therewith a dye image-forming material which is processing composition soluble and diffusible as a function of exposure of the photosensitive silver halide emulsion layer to incident actinic radiation; a polymeric layer dyeable by said dye image-forming material; a second dimensionally stable layer transparent to incident actinic radiation; and means securing said layers in substantially fixed relationship;
  • a photographic film unit as defined in claim 1 wherein said means for interposing said polymeric layer comprises disposing a polymeric layer permeable to processing composition solubilized dye image-forming material and adapted to be cross-linked by contact with metal ion capable of cross-linking its polymeric component between said dyeable polymeric layer and the photosensitive silver halide emulsion layer next adjacent and disposing metal ion adapted to cross-link said dye image-forming material permeable polymeric layer to provide a metal ion cross-linked polymeric layer, in a processing composition permeable layer of said photosensitive element as a metallic salt adapted to solubilized solubilized by contact with distributed processing composition and to diffuse into contact with said dye image-forming material permeable polymeric layer in a concentration effective, subsequent to substantial dye image-forming material transfer to said dyeable polymeric layer from said associated silver halide emulsion layer as a function of exposure of said emulsion layer, to provide said impermeable metal ion cross-linked polymeric layer.
  • a photographic film unit as defined in claim- 1 wherein said metal ion cross-linked polymeric layer is impermeable to dye image-forming material and means for interposing said dye image-forming material impermeable polymeric layer comprises disposing a polymeric layer penneable to processing composition solubilized dye image-forming material and adapted to be cross-linked by contact with metal ion capable of cross-linking its polymeric component between said dyeable polymeric layer and the photosensitive silver halide emulsion layer next adjacent and disposing metal ion adapter to cross-link said dye image-forming material permeable polymeric layer to provide said dye image-forming material impermeable metal ion cross-linked polymeric layer in said processing composition as retained in said rupturable container and adapted to be discharged in functional contact with said dye image-forming material permeable polymeric layer in a concentration effective, subsequent to substantial dye image-forming material transfer to said dyeable polymeric layer from said associated silver halide emulsion layer as a function of exposure of said emulsion layer
  • a photographic film unit as defined in claim 1 wherein said means for interposing said polymeric layer comprises disposing a film-forming polymer adapted to he cross-linked by contact with metal ion capable of cross-linking its polymeric component in said processing composition retained in said rupturable container and adapted upon distribution of said processing composition between said dyeable polymeric layer and the photosensitive silver halide emulsion layer next adjacent thereto to provide a substantially continuous dye image-forming material permeable polymeric layer, and said metal ion disposed as a metallic salt in a processing composition permeable layer of said photosensitive element and adapted to be solubilized by contact with distributed processing composition and to diffuse, subsequent to substantial dye image-forming material transfer to said dyeable polymeric layer from said associated silver halide emulsion layer as a function of exposure of said emulsion layer, to said dye image-forming material permeable polymeric layer in a concentration effective to provide a dye image-forming material impermeable metal ion cross-linked polymeric layer.
  • a photographic film unit as defined in claim 4 wherein said film-forming polymeric material comprises carboxymethyl cellulose.
  • a photographic film unit as defined in claim 4 wherein said film-forming polymeric material comprises carboxymethyl hydroxyethyl cellulose.
  • said photosensitive element comprises at least two selectively sensitized silver halide emulsion layers each having a dye which dye is a silver halide developing agent of a predetermined color associated therewith, each of said dyes soluble and diffusible in processing composition as a function of the point-to-point degree of exposure of the respective emulsion associated therewith.
  • each of said selectively sensitized photosensitive silver halide emulsions has predominant spectral sensitivity to separate regions of the spectrum and the dye associated with each of said silver halide emulsion layers possesses a spectral absorption range subsequent processing substantially complementary to the predominant sensitivity range of its associated emulsion layer.
  • a photographic film unit as defined in claim 14 including at least one polymeric acid layer positioned intermediate at least one of said first dimensionally stable layers and the photosensitive silver halide emulsion layer next adjacent thereto, and said second dimensionally stable layer and the dyeable polymeric layer adjacent thereto, said processing composition comprises an aqueous alkaline processing composition possessing a first pH at which said dye is soluble and diffusible and said polymeric acid layers possess sufiicient acid capacity to reduce said processing composition from said first pH to a second pH at which said dye is substantially nondiffusible subsequent to substantial dye image diffusion to said dyeable polymeric layer from said silver halide emulsion layer as a function of exposure of said emulsion layer.
  • a photographic film unit as defined in claim 21 which is adapted to be processed by passing said unit between a pair of juxtaposed pressure-applying members and which comprises, in combination:
  • a photosensitive element including a composite structure containing, as essential layers, in sequence, a dimensionally stable liquid impermeable opaque layer; a redsensitive silver halide emulsion layer having associated therewith cyan dye; a green-sensitive silver halide emulsion layer having associated therewith magenta dye; a blue-sensitive silver halide emulsion layer having associated therewith yellow dye, each of said cyan, magenta and yellow dyes being silver halide developing agents and being soluble and diffusible in aqueous alkaline processing composition at a first pH; an alkaline solution permeable transparent polymeric layer dyeable by said dyes; an alkaline solution permeable transparent polymeric acid .layer containing sufficient acidifying capacity to effect reduction of an aqueous alkaline processing composition having said first pH to a second pH at which said dyes are substantially nondifi'usible; a dimensionally stable liquid impermeable transparent layer; and means securing said layers in substantially fixed relationship;
  • a rupturable container retaining an aqueous alkaline processing composition fixedly positioned and extending transverse a leading edge of said photosensitive element to effect unidirectional discharge of said containers processing composition between said dyeable polymeric layer and said blue-sensitive silver halide emulsion layer upon application of compressive pressure to said container, said aqueous alkaline processing composition possessing said first pH, opacifying agent in a quantity sufi'rcient to mask said cyan, magenta and yellow dyes associated with said red-, greenand blue-sensitive silver halide emulsion layers and a film-forming polymer adapted to be cross-linked by contact with metal ion capable of cross-linking its polymeric component in a quantity sufficient to provide a substantially continuous, alkaline processing composition solubilized cyan, magenta and yellow dye permeable polymeric layer upon distribution of said aqueous alkaline processing composition intermediate said dyeable polymeric layer and said bluesensitive silver halide emulsion layer; and said metal ion adapted
  • a photographic film unit as defined in claim 26 including said metal ion is disposed in a processing composition permeable layer.
  • a process for forming transfer images in color which comprises, in combination, the steps of:
  • exposing a photographic film unit which is adapted to be precessed by passing the unit between a pair of juxtaposed pressure-applying members and which includes, in combination, a composite structure comprising a first dimensionally stable layer opaque to incident actinic radiation; a photosensitive silver halide layer having associated therewith a dye image-forming material which is processing composition soluble and diffusible as a function of exposure of the photosensitive silver halide layer to incident actinic radiation; a polymeric layer dyeable by said dye image-forming material; a second dimensionally stable layer transparent to incident actinic radiation; and means securing said layers in substantially fixed relationship; and
  • a rupturable container retaining a processing composition containing an opacifying agent in a quantity sufficient to mask said dye image-forming material fixedly positioned and extending transverse a leading edge of said photosensitive element to effect unidirectional discharge of said containers alkaline processing composition between said dyeable polymeric layer and the photosensitive silver halide layer next adjacent thereto;
  • a polymeric layer inter mediate said dyeable polymeric layer and said silver halide layer next adjacent; said polymeric layer comprising a polymeric material having a metal ion capable of cross linking its polymeric component associated therewith;
  • a process as defined in claim 30 which includes the step of disposing a polymeric layer permeable to processing composition solubilized dye image-forming material and adapted to be cross-linked by contact with said metal ion between said dyeable polymeric layer and the photosensitive silver halide emulsion layer next adjacent and disposing metal ion adapted to cross-link said dye image-forming material permeable polymeric layer to provide a dye image-forming material impermeable metal ion cross-linked polymeric layer in a processing composition permeable layer of said photosensitive element as a metallic salt adapted to be solubilized by contact with distributed processing composition and to diffuse into contact with said dye image-forming material permeable polymeric layer in a concentration effective, subsequent to substantial dye image-forming material transfer to said dyeable polymeric layer from said associated silver halide emulsion layer as a function of exposure of said emulsion layer, to provide said dye image-forming material impermeable metal ion cross-linked polymeric layer.
  • a process as defined in claim 30 which includes the step of disposing a polymeric material penneable to processing composition solubilized dye image-forming material and adapted to be cross-linked by contact with said metal ion between said dyeable polymeric layer and the photosensitive silver halide emulsion layer next adjacent and disposing said metal ion adapted to cross-link said dye image-forming material permeable polymeric layer to provide a dye imagefonning material impermeable metal ion cross-linked polymeric layer in said processing composition as retained in said rupturable container and adapted to be discharged in functional contact with said dye image-forming material permeable polymeric material in a concentration efiective, subsequent to substantial dye image-fuming material transfer to said dyeable polymeric layer from said associated silver halide emulsion layer as a function of exposure of said emulsion layer, to provide said dye image-forming material impermeable metal ion cross-linked polymeric layer.
  • a process as defined in claim 30 which includes the step of disposing a film-forming polymer adapted to be crosslinked by contact with said metal ion in said processing composition retained in said rupturable container and adapted upon distribution of said processing composition between said dyeable polymeric layer and the photosensitive silver halide emulsion layer next adjacent thereto to provide a substantially continuous dye image-forming material permeable polymeric layer, and said metal ion disposed as a metallic salt in a processing composition permeable layer of said photosensitive element and adapted to be solubilized by contact with distributed processing composition and to diffuse, subsequent to substantial dye image-forming material transfer to said dyeable polymeric layer from said associated silver halide emulsion layer as a function of exposure of said emulsion layer, to said dye image-forming material permeable polymeric layer in a concentration effective to proved a dye image-forming material impermeable metal ion cross-linked polymeric layer.
  • a process as defined in claim 33 wherein said film-forming polymeric material comprises carboxymethyl cellulose.
  • a process as defined in claim 33 wherein said film-fanning polymeric material comprises carboxymethyl hydroxyethyl cellulose.
  • a process as defined in claim 38 wherein said metal ion is selected from the group consisting of: cadmium, magnesium, calcium, zinc, zirconium, aluminum, chromium, and
  • dimensionally stable layer is transparent to incident actinic radiation.
  • said dye image-forming material is a dye which is a silver halide developing agent.
  • said photographic film unit includes at least two selectively sensitized silver halide emulsion layers, each of said silver halide emulsions having associated therewith a dye, which is a silver halide developing agent, of predetermined color.
  • each of said selectively sensitized silver halide emulsion layers possesses predominant spectral sensitivity to a separate region of the spectrum and the dye associated with each of said emulsion layers possesses a spectral absorption range subsequent to processing substantially complementary to the predominant sensitivity range of its associated emulsion.
  • said composite structure includes at least one polymeric acid layer positioned intermediate at least one of said first dimensionally stable layers and the next adjacent photosensitive silver halide layer, and said second dimensionally stable layer and the next adjacent dyeable polymeric layer and said polymeric acid layers containing sufficient acidifying groups to effect reduction of an aqueous alkaline processing composition possessing a first pH at which said dyes are substantially soluble and difiusible to a second pH at which said dyes are substantially nondiffusible and including the step of transferring, by diffusion, subsequent to substantial transfer image formation, a sufi'rcient portion of the ions of said alkaline processing solution to said polymeric acid layers to thereby reduce the alkalinity of said solution from said first pH to said second pH.
  • aqueous alkaline processing composition additionally contains a filmforming polymeric material adapted to be cross-linked by contact with said metal ion at said second pH in a quantity sufficient to provide said polymeric layer intennediate said said dyeable polymeric layer and said silver halide layer upon said distribution of said processing composition.
  • a process as defined in claim 30 wherein said opacifying agent is titanium dioxide.
  • a process as defined in claim 30 including the step of separating said container from said composite structure subsequent to substantial transfer image formation.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Structural Engineering (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
  • Color Printing (AREA)
US42394A 1970-06-01 1970-06-01 Photographic products and processes utilizing a polyvalent metal ion-cross-linked polymeric layer Expired - Lifetime US3619155A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US4239470A 1970-06-01 1970-06-01

Publications (1)

Publication Number Publication Date
US3619155A true US3619155A (en) 1971-11-09

Family

ID=21921692

Family Applications (1)

Application Number Title Priority Date Filing Date
US42394A Expired - Lifetime US3619155A (en) 1970-06-01 1970-06-01 Photographic products and processes utilizing a polyvalent metal ion-cross-linked polymeric layer

Country Status (9)

Country Link
US (1) US3619155A (enrdf_load_stackoverflow)
JP (1) JPS5344823B1 (enrdf_load_stackoverflow)
BE (1) BE767870R (enrdf_load_stackoverflow)
CA (1) CA944208A (enrdf_load_stackoverflow)
DE (1) DE2127144C3 (enrdf_load_stackoverflow)
FR (1) FR2095706A6 (enrdf_load_stackoverflow)
GB (1) GB1355133A (enrdf_load_stackoverflow)
IT (1) IT989594B (enrdf_load_stackoverflow)
NL (1) NL171842C (enrdf_load_stackoverflow)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4021241A (en) * 1974-04-12 1977-05-03 Polaroid Corporation Diffusion transfer processing solutions with carboxymethyl hydroxyethyl cellulose
US4239847A (en) * 1978-09-21 1980-12-16 Eastman Kodak Company Photographic elements containing polymers which coordinate with metal ions
US4282305A (en) * 1979-01-15 1981-08-04 Eastman Kodak Company Receiving elements for image transfer film units
US4299895A (en) * 1978-09-21 1981-11-10 Eastman Kodak Company Photographic elements containing polymers which coordinate with metal ions
EP0057508A1 (en) * 1981-01-12 1982-08-11 EASTMAN KODAK COMPANY (a New Jersey corporation) Photosensitive/film unit containing zinc compound to increase dye stability
US4629667A (en) * 1985-03-29 1986-12-16 Minnesota Mining And Manufacturing Company White reflective coating
US4649095A (en) * 1983-10-06 1987-03-10 Fuji Photo Film Co., Ltd. Color diffusion transfer photographic film unit containing aluminum compound
US5346800A (en) * 1993-10-06 1994-09-13 Polaroid Corporation Image-receiving element for diffusion transfer photographic film products

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4355091A (en) * 1980-08-25 1982-10-19 Polaroid Corporation Polymeric neutralizing layer with temporary crosslinks from an organo-metallic crosslinking agent
CN110093113A (zh) * 2019-05-17 2019-08-06 新纶科技（常州）有限公司 一种保护膜及其制备方法和用途

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3384483A (en) * 1964-03-23 1968-05-21 Eastmean Kodak Company Multicolor dye developer image transfer systems

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3415644A (en) * 1967-03-10 1968-12-10 Polaroid Corp Novel photographic products and processes

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3384483A (en) * 1964-03-23 1968-05-21 Eastmean Kodak Company Multicolor dye developer image transfer systems

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4021241A (en) * 1974-04-12 1977-05-03 Polaroid Corporation Diffusion transfer processing solutions with carboxymethyl hydroxyethyl cellulose
US4239847A (en) * 1978-09-21 1980-12-16 Eastman Kodak Company Photographic elements containing polymers which coordinate with metal ions
US4299895A (en) * 1978-09-21 1981-11-10 Eastman Kodak Company Photographic elements containing polymers which coordinate with metal ions
US4282305A (en) * 1979-01-15 1981-08-04 Eastman Kodak Company Receiving elements for image transfer film units
EP0057508A1 (en) * 1981-01-12 1982-08-11 EASTMAN KODAK COMPANY (a New Jersey corporation) Photosensitive/film unit containing zinc compound to increase dye stability
US4356250A (en) * 1981-01-12 1982-10-26 Eastman Kodak Company Use of zinc salts to increase dye stability
US4649095A (en) * 1983-10-06 1987-03-10 Fuji Photo Film Co., Ltd. Color diffusion transfer photographic film unit containing aluminum compound
US4629667A (en) * 1985-03-29 1986-12-16 Minnesota Mining And Manufacturing Company White reflective coating
US5346800A (en) * 1993-10-06 1994-09-13 Polaroid Corporation Image-receiving element for diffusion transfer photographic film products

Also Published As

Publication number Publication date
NL7107484A (enrdf_load_stackoverflow) 1971-12-03
JPS5344823B1 (enrdf_load_stackoverflow) 1978-12-01
NL171842C (nl) 1983-05-16
FR2095706A6 (enrdf_load_stackoverflow) 1972-02-11
GB1355133A (en) 1974-06-05
DE2127144B2 (de) 1974-01-31
DE2127144C3 (de) 1975-01-16
BE767870R (fr) 1971-11-29
NL171842B (nl) 1982-12-16
CA944208A (en) 1974-03-26
DE2127144A1 (de) 1972-12-14
IT989594B (it) 1975-06-10

Similar Documents

Publication Publication Date Title
US3415644A (en) Novel photographic products and processes
US3594165A (en) Novel photographic products and processes
US3415645A (en) Opaque permeable polymeric layer in photo-sensitive element
US3415646A (en) Novel photographic products and processes
US3619155A (en) Photographic products and processes utilizing a polyvalent metal ion-cross-linked polymeric layer
US3473925A (en) Photographic diffusion transfer color process and film unit for use therein
US3625685A (en) Photographic color diffusion-transfer element comprising aqueous film-forming synthetic polymer suspension layers intermediate its sensitive layers and processes for their use
US3615422A (en) Photographic products and processes
US3594164A (en) Photographic color diffusion transfer process and film unit for use therein
US3888669A (en) Photographic products and processes with barrier layers for diffusable dyes
US3579333A (en) Multicolor diffusion transfer photographic products and processes with a developing composition comprising a desensitizing agent
US3748129A (en) Dye image providing materials within diffusion transfer barrier layers
US3679409A (en) Color diffusion transfer processes and elements for use thereon with incorporated image-forming material impermeable layer
US3734727A (en) Photographic products and processes
US3772026A (en) Colorless precursor of alkyl viologen as filter agent in photographic film
US3647435A (en) Integral negative/positive color diffusion transfer process film unit employing in-situ generated visible light-reflecting agent
US4003744A (en) Photographic products with photosensitive layers of same spectral sensitivity and different speed
US3615421A (en) Novel photographic products and processes
US3615543A (en) Multicolor photographic element comprising an oxacyanine sensitizing dye
US3573043A (en) Photographic diffusion transfer color process and composite film unit for use therein
US3832173A (en) Novel photographic products and processes
US3836365A (en) Novel photographic products and processes
US3816125A (en) Photographic products and processes
US3707370A (en) Color diffusion transfer film units comprising a layer which contains a synthetic polymer-benzenoid silver halide developing agent complex and process for their use
US3816126A (en) Novel photographic products and processes