US3778271A - Photographic products comprising an opacifying agent in association with a reflecting agent - Google Patents

Photographic products comprising an opacifying agent in association with a reflecting agent Download PDF

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US3778271A
US3778271A US00191941A US3778271DA US3778271A US 3778271 A US3778271 A US 3778271A US 00191941 A US00191941 A US 00191941A US 3778271D A US3778271D A US 3778271DA US 3778271 A US3778271 A US 3778271A
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Prior art keywords
layer
film unit
image
silver halide
dye
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US00191941A
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English (en)
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E Land
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Polaroid Corp
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Polaroid Corp
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C8/00—Diffusion transfer processes or agents therefor; Photosensitive materials for such processes
    • G03C8/42—Structural details
    • G03C8/44—Integral units, i.e. the image-forming section not being separated from the image-receiving section

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  • ABSTRACT Film assemblies in the nature of a self developing film which comprise a photosensitive element including an opaque support carrying photosensitive silver halide having associated diffusion transfer process dye image-providing material; an image-receiving element including a transparent support carrying a diffusion transfer image-receiving layer and a reflecting layer; rupturable container means retaining a fluid processing composition for distribution between the photosensitive and the image-receiving elements; and including opacifying agent disposed in the fluid processing composition and/or integral with or as a layer on the surface of the image receiving element's reflecting layer opposite the transparent support. for processing external a camera in which the film assembly is exposed and adapted to provide a color reflection print as a function of the film units photoexposure.
  • the film unit is specifically adapted to be withdrawn from the camera between pressure-applying members which effect release of the fluid processing composition for production of the dye transfer image.
  • formation of the color reflection print may be viewed through the image-receiving elements transparent support against the background.
  • provided by the elements reflection layer and the reflection layer, taken together with the opacifying agent, is specifically adapted to protect the photosensitive silver halide from exposure during processing in the presence of radiation incident on the viewing surface.
  • ATTORNEYS PATENTED DEC 1 I975 MEI30F4 MGE INVENTOR. EDWIN H. LAND @Jww n mm! M mm! W 77?. you! ATTORNEYS mm mm PHOTOGRAPHIC PRODUCTS COMPRISING AN OPACIFYING AGENT IN ASSOCIATION WITH A REFLECTING AGENT BACKGROUND OF THE INVENTION
  • the present invention is concerned with photo graphic film units, particularly adapted for employment in a photographic film pack or film magazine of the type shown in US. Pat. No. 3,080,805, issued Mar. 12, 1963, in the name of Joel A.
  • each film unit includes, in combination, a first photosensitive element positioned for exposure within the container; a second nonphotosensitive element, preferably a print-receiving element, adapted to be superposed with the photosensitive element during withdrawal of the film unit from the container, following exposure thereof; and frangible container means particularly adapted to releasably retain a fluid processing composition for distribution between the superposed photosensitive and print-receiving elements subsequent to photoexposure of the film unit.
  • the film pack or container includes an exposure aperture adapted to permit exposure of the photosensitive element; a removable closure element located across the exposure aperture; at least one film unit; and an opening permitting withdrawal of the closure element and film units from the container successively through this opening.
  • the closure element and each film unit includes a leader adapted to project from the film pack through the opening whereby to provide means for selectively withdrawing the closureelement, or a film unit, from the film pack into contact, and in engagement, with means adapted to provide individual distribution of the retained fluid processing composition, between superposed photosensitive and nonphotosensitive elements.
  • Film packs of this type are intended to be employed in photographic apparatus, such as a camera, which include means for maintaining a film pack in position for exposure, means for selectively exposing the photosensitive element of successive film units of the pack, and means for engaging each film unit during withdrawal from the pack, subsequent to photoexposure, and distributing the retained processing fluid between, and in contact with, the contiguous photosensitive andselfceiving elements of the film unit, for effecting photographic diffusion transfer processing of the respective, photoexposed film unit. Processing of each film unit may thus be effected manually by grasping a leader attached to the film unit and withdrawing the leader and film unit from both the pack and the camera.
  • the photosensitive sheet element In photographic diffusion transfer processing, the photosensitive sheet element is normally first exposed and then biased into superposed relationship with a second sheet element, which is, in general, photographically inert and aids in the controlled distribution of the processing composition.
  • the photosensitive element may contain an integral print-receiving stratum or the second sheet element may comprise a transfer imagereceiving element.
  • the contiguous sheet elements are moved relative to, and between, a pair of suitably opposed members such as gapped parallel pressure rollers or platens.
  • color photographic reproduction may be provided by diffusion transfer processing such as exposing a photoresponsive material, for example, photosensitive silver halide layer having associated therewith dye image-providing material which is processing composition diffusible, as a function ofexposure of its associated photosensitive silver halide, such as the dye image-providing materials disclosed in US. Pat. Nos.
  • diffusion transfer processing such as exposing a photoresponsive material, for example, photosensitive silver halide layer having associated therewith dye image-providing material which is processing composition diffusible, as a function ofexposure of its associated photosensitive silver halide, such as the dye image-providing materials disclosed in US. Pat. Nos.
  • the present invention is directed to a film assembly for producing color reflection prints employing a film pack or magazine type unit.
  • the assembly is composed of a first sheet element comprising a photosensitive structure including, in essence, an opaque support carrying a photoresponsive material, such as photosensitive silver halide crystals having associated therewith a dye image-providing material which is processing composition diffusible as a function of the photoexposure of associated photosensitive silver halide; a second sheet element comprising, in essence, a transparent support carrying, in order, a layer adapted to receive the image formed as a function of photo-exposure of the photoresponsive material and a dye imageproviding material permeable visible light-reflecting layer, adapted to be superposed over the exposure surface of the photosensitive element, with the respective supports outermost, subsequent to exposure of the photoresponsive material; frangible fluid retaining means adapted to discharge processing composition retained therein between the first and second sheet elements; means including a leader for coupling the first sheet element and the second sheet element and withdrawing same in superposed relationship from the exposure apparatus; and an opacifying agent disposed integral with and or/ contiguous the surface of the reflecting layer opposite
  • the described film assembly is first exposed in an apparatus such as a hand-held camera by radiation incident on the exposure surface of the first sheet element and then biased into superposed relationship with the second sheet element to permit removal from the apparatus and processing of the exposed photoresponsive material under ambient light conditions external to the exposure device. Substantially contemporaneous with the removal of the film assembly from the camera, the frangible container is ruptured, discharging its contents intermediate the opposed surfaces of the first and second sheet elements, and the leader and fluid retaining means are thereafter optionally detached from association with the remainder of the assembly.
  • an apparatus such as a hand-held camera by radiation incident on the exposure surface of the first sheet element and then biased into superposed relationship with the second sheet element to permit removal from the apparatus and processing of the exposed photoresponsive material under ambient light conditions external to the exposure device.
  • the frangible container is ruptured, discharging its contents intermediate the opposed surfaces of the first and second sheet elements, and the leader and fluid retaining means are thereafter optionally detached from association with the remainder of the assembly.
  • FIG. I is a fragmentary perspective view of a photographic film unit embodying the invention.
  • FIG. 2 is a plan view of the film unit of FIG. 1;
  • FIG. 3 is a perspective view of a film pack comprising an assemblage of film units
  • FIG. 4 is a longitudinal sectional view taken substantially midway between the sides of the film pack of FIG.
  • FIG. 5 is a diagrammatic sectional view taken sub stantially midway between the sides of the film pack showing one film unit with the components thereof spaced apart to more clearly illustrate the construction and arrangement of the film unit;
  • FIG. 6 is an elevational view, partially in section, of photographic apparatus in the form ofa camera for employing film units embodying the invention
  • FIG. 7 is a fragmentary sectional view, similar to FIG. 6, illustrating initiation of an initial passage of one film unit between a pair of opposed pressure-applying rolls during removal of the film unit from the camera apparatus of FIG. 6, subsequent to photoexposure;
  • FIG. 8 is a fragmentary sectional view, similar to FIG. 7, illustrating further passage of the film unit between the pair of opposed pressure rolls, rupture of the frangible container and distribution of its fluid processing composition contents between, and in contact with, the opposed surfaces of the superposed sheet elements of the film unit;
  • FIG. 9 is a fragmentary sectional view, similar to FIG. 8, illustrating completion of the passage of the film unit between the pair of opposed pressure rolls, the laminate formed by distribution of the fluid processing composition between the superposed sheet elements.
  • the preferred form of the film assemblage for the production ofa dye reflection print comprises a photosensitive film unit specifically adapted to be processed in the presence of ambient radiation and the dye reflection print image to be viewed during and subsequent to processing without separation of film unit components
  • a photosensitive sheet element comprising an opaque support carrying on one surface a photoresponsive material having associated therewith a dye imageproviding material, which is processing composition diffusible as a function of the photoexposure of associated photoresponsive material adapted to be exposed by incident actinic radiation to produce photographic information recordation
  • a second dye image receptive sheet element comprising a transparent support carrying on one surface, in order, an image-receiving layer adapted to receive by diffusion transfer processing an image as a function of the exposure of the photoresponsive material and a dye image-providing material permeable visible light-reflecting layer, adapted to be biased into superposed relationship contiguous the exposure surface of the first photosensitive sheet element subsequent to exposure
  • a photosensitive film unit specifically adapted to be processed in the presence of ambient radiation and the
  • the preferred form or film pack or magazine embodying the designated film units comprises a plurality of the film assemblies, each adapted to be individually exposed in a camera, enclosed in a light-proof container which allows the film units to be sequentially exposed.
  • the container includes a forward wall having an exposure aperture therein and an opening in one end through which film assemblies can be individually withdrawn with the photosensitive and second sheet elements of each film unit in superposed relation.
  • the photosensitive film units are positioned together within the container underlying the exposure aperture with the exposure surface of the first photosensitive sheet element uppermost and the second image-receptive sheet elements are arranged together, apart from, and behind the photosensitive elements adjacent the opening through which the film units are withdrawn so that following the exposure of the photosensitive sheet element of each film unit, the photosensitive element is moved, by drawing on the leader of the film unit, into superposition with the second element of the film unit and the film unit is then withdrawn from the container through the opening.
  • the film pack is initially provided with a cover element or sheet mounted within the container and extending across the exposure aperture for closing the aperture against the admission of light.
  • the cover element also includes a leader extending from the container through the opening and being removable therethrough.
  • the film pack is employed by being positioned in a camera, including a pair of juxtaposed pressureapplying members, with the opening located adjacent the pressure-applying members and the exposure aperture disposed approximately in the exposure plane of the camera.
  • the leaders of the film units and cover element extend from the pack and from the camera where the last-mentioned leader may be grasped for withdrawing the cover element from the pack and camera to allow the photosensitive elements of the pack to be exposed. After the photosensitive elements of each successive film unit is exposed, that film unit is then withdrawn from the container and camera between the pressure-applying members by withdrawing the leader of the first film unit and of successive film units from the container and camera.
  • color reflection prints can be provided employing photographic diffusion transfer processing effected external the camera in which the film units were subjected to exposure and in the presence of ambient radiation.
  • FIGS. 1 through 9 of the drawings wherein there are illustrated film units and an assemblage of film units in the form of a film pack.
  • Each film unit designated 10 comprises a generally rectangular photosensitive color sheet element 11, comprising an opaque support carrying on one surface a photosensitive silver halide layer and a second imagereceptive sheet element 18 adapted to be superposed on exposure surface 19 of the element opposite the first opaque support.
  • Photosensitive sheet element 11 possesses a first leading section 20 approximately equal in width to element 11 and provides means for mounting rupturable container 21 of processing fluid, and includes a leading end section 22.
  • Image-receptive sheet element 18 is approximately equal in width to element 11 and includes a tapered leading end section 23 approximately equal in dimensions to tapered end section 22 of sheet 11.
  • Side guides 24 are secured to the lateral edges of sheet 18 coextensive the length of element 11 whereby to provide a gap control between sheet 18 and element 11 during processing, and the lateral boundaries of the element 11 may be secured to the corresponding lateral boundaries of sheet 18 at the respective interface therebetween in any analagous manner as to facilitate retention of the processing fluid intermediate sheet 18 and element 11.
  • Tapered end sections 22 and 23 cooperate to define the leading end section of film unit 10 to be advanced between the pressure-applying members as further defined hereinafter.
  • the length of sheets 11 and 18 is substantially equal and by virtue of this arrangement, the sheets are readily superposed in registered relation during the processing of the film unit.
  • a trailing end section 25 of sheet 11 extends beyond the trailing edge 26 of element 11 to coact with trailing end section 27 of sheet 18 to trap any excess processing fluid which may be carried beyond the trailing ends of the photosensitive element 11 during distribution of the processing fluid.
  • Distribution of the processing fluid is effected by advancing sheets 11 and 18 and container 21 of processing fluid, the former in superposition, relative to and between a pair of juxtaposed pressure-applying members 29 and 30.
  • the pressure-applying members e.g., opposed suitably gapped rolls, apply compressive pressure to the sheets progressively, commencing in the area of the container, to cause the ejection of the fluid contents of the container between and in contact with the opposed surfaces of the sheet 18 and element 11.
  • spacing members 31 may be provided on trailing end section 27 adjacent the margins thereof for spacing apart the pressure-applying members to provide a gap between trailing end section 25 of sheet 11 and trailing end section 27 of sheet 18 in which any excess processing fluid may be collected and retained.
  • leader sheet 12 having a first section 20 in which the leader sheet 12 is coupled with the photosensitive laminate.
  • First section 20 is approximately equal in width to the photosensitive laminate and provides means for mounting rupturable container 21.
  • leader sheet 12 includes tapered end section 22.
  • Imagereceiving laminate 17 is shown mounted on a carrier sheet 13 having an intermediate section 14 approximately equal in width to the image-receiving laminate and having a generally rectangular opening 15 therein defining the area of the image-receiving laminate in which image formation occurs.
  • Carrier sheet 13 includes a leading end section 23 having a tapered end portion 28 similar to tapered end section 22 and secured thereto intermediate the ends of tapered end section 22 and tapered end portion 28 of leading end section 23. As shown, tapered end section 22 and end portion 28 cooperate to define the leading end section of the film unit which is advanced between the pressureapplying members 29 and 30. Where desired, intermediate section 14 of carrier sheet 13 may be secured to the external surface of image-receiving laminate 17 so that portions of the intermediate section bordering on opening 15 may provide a mask. for defining image area.
  • the length of leader sheet 12 between the leading edge of photosensitive laminate 16 and the point of attachment of leader sheet 12 to carrier sheet 13 is substantially equal to the length of carrier sheet 13 between its point of attachment to the leader sheet and the leading edge of image-receiving laminate 17.
  • photosensitive laminate 16 and image-receptive laminate 17 are superposed in registered relation during rocessing of film unit 10.
  • a trailer sheet 25 is provided secured to the trailing edge of photosensitive laminate 16 for cooperation with the opposed trailing end section 27 of carrier sheet 13 to trap excess processing, fluid which may be transported beyond the trailing ends of the photosensitive and image-receptive laminates during distribution of processing composition.
  • the rupturable container is of the type shown and described in US. Pat. Nos. 2,543,181; 2,634,886; 2,653,732; 2,674,532; 2,702,146; 2,723,051; 2,750,075; 3,056,491; and 3,056,492, and may comprise a rectangular blank of fluid-and air-impervious sheet material folded longitudinally upon itself to form two walls which are sealed to one another along the longitudinal and end margins to form a cavity in which the processing fluid is contained.
  • Longitudinal marginal seal 32 is made weaker than the end seal so as to become unsealed in response to hydraulic pressure generated within the fluid contents of the container by the application of compressive pressure to the walls of the container.
  • Container 21 is mounted on sheet 11 with the longitudinal marginal seal directed toward the leading edge 33 of element 11.
  • Bib sheet 34 is secured to sheet 11 at lateral edges 35 and 36, center area 37, trailing edge 38 of container 21, and leading edge 33 of element 11, and facilitates restricted unidirectional flow of fluid contents 39 upon compressive rupture of container 21.
  • Edge 40 of bib sheet 34 extends beneath leading edge 33 of element 11. Thus, the flow of fluid contents 39 from container 21 is directed beneath bib sheet 34 and distributed intermediate element 11 and sheet 18.
  • FIGS. 3 and 4 of the drawings A film pack or assemblage of film units is shown in FIGS. 3 and 4 of the drawings.
  • This film pack designated 41, comprises a generally parallelepiped-shaped container or box 42 for holding and enclosing a plurality of film units 10.
  • Container 42 is shown as comprising two sections, including a forward section having a forward wall 43, side walls 44, a trailing end wall 45, and a leading end wall 46.
  • Forward wall 43 is provided with a generally rectangular exposure aperture 47 for transmitting light for exposing the photosensitive sheets of film units carried within the container.
  • Leading end wall 46 comprises only a partial wall, i.e., it does not extend rearwardly to the same extent as the side walls, which cooperates with the rear section of the container to provide a passage 48 at the leading end of the container through which film units 10 carried by the container are withdrawn.
  • the rear section of the container comprises a rear wall 49 secured to side walls 44 and formed preferably of a resilient sheet metal.
  • each film unit within container 41 is illustrated in FIGS. 1 and 5; and the arrangement of a plurality of film units (two are shown) is illustrated in FIG. 4.
  • Each film unit is arranged with the photosensitive and second sheets in overlying relation with the photosensitive layer of element 11 facing outward and with the reflecting layer of image-receptive sheet 18 which is superposed therewith, during processing, facing inwardly in the same direction.
  • Leading end section 20 of sheet 11 is folded or curved adjacent the leading edge 33 of element 11 intermediate that edge and container 21, and leading end section 23 of sheet 18 is similarly folded adjacent the leading edge of the sheet so that leading portions of leading end sections 20 and 23 interconnect sheet 11 and 18 in the stated spacial arrangement upon superpositioning of the sheets; and trailing end section 25 of sheet 11 is disposed adjacent, respectively, trailing end section 27 of sheet 18.
  • the film pack is provided with a generally flat, rectangular pressure plate 50 located intermediate sheet 1 1 and the other portions of the film unit for supporting element 11 against the inner surface of forward wall 43 in position for exposure through aperture 47.
  • Pressure plate 50 includes a rolled end section 51 around which extends the curved portion of sheet 16.
  • Rolled end section 51 is provided for guiding photosensitive element 11 around the end of the pressure plate in a manner to be described hereinafter.
  • the major portion of first section 20 of sheet 11 rupturable container 21 mounted thereon, tapered section 22 and the leading tapered end section 23 of sheet 18 are located behind pressure plate 50 between the latter and sheet 18.
  • Pressure plate 50 is provided with lateral flanges 52 disposed adjacent side walls 44 of the container.
  • Rear wall 49 of the housing is provided with springs 53 formed from the rear wall and biased inwardly for engaging lateral flanges 52 and biasing pressure plate 50 toward forward wall 43 to retain element 11 in position for exposure.
  • Rear wall 49 is also provided with a U-shaped opening or enlarged notch 54 in the end portion thereof adjacent opening 48 the purpose of opening 48 to be further described hereinafter.
  • the means for withdrawing each film unit 10 from container 41 with element 11 and sheet 18 in superposition and advancing tapered end sections 22 and 23 between a pair of pressure-applying members comprises a relatively narrow elongated leader 55 secured at the trailing end of the leader to tapered end section 22 of sheet 1 1 preceding the point of attachment of the tapered end section 22 to tapered end portion 23 of sheet 18.
  • Leader 55 is of substantially uniform width throughout its length.
  • the areas of adherence of leader 55 to tapered end section 22 extend substantially in the direction of movement of the leader, and comprise any suitable adhesive material which will form a bond preferably at least equal in strength to the sheet materials (paper) comprising the leader and tapered end section, sufiicient in resistance to the application of tension, in a direction of the plane of tapered end section 22, to prevent shearing.
  • the adhesive bond is such that the application of a suitable shearing force to leader 55, effective by applying tension to the leader in a direction at an angle from the plane of tapered end section 22, causes leader 55 to disengage from contact with tapered end section 22.
  • Leader 55 extends from container 41 through opening 48 therein and, when drawn from the container, advances element 11 around rolled end section 51 of pressure plate 50 into superposition with a second sheet 18 and then advances the two sheets in superposition within the container towards opening 48.
  • tapered end section 22 of sheet 11 is required to commence rolling upon itself toward the opening in response to movement of tapered end section 22 of sheet 11 toward the same opening. It is for this reason that section 22 and portion 23 are tapered, since this provides for the Weakest portion of end portion 22 in the area where the end portion is required to commence rolling.
  • Means may also be provided for preventing movement of elements underlying the foremost element 11 as the latter is moved from exposure position around the end of the pressure plate.
  • Film pack 41 is provided with means for initially sealing aperture 47 against the admission of light until the pack has been loaded into the camera in which it is to be employed.
  • This light-sealing means comprises a cover sheet 56 (double) of a light-impervious material located between the foremost photosensitive sheet and forward wall 43 across opening 47. Cover sheet 56 extends around the curved end of the pressure plate behind the latter to a position against rear wall 49 with the leading end of the cover sheet locatediadjacent passage 48.
  • An elongated leader section 108 similar to leader 55, provides means for withdrawing cover sheet 56 from container 41 after the container has been loaded into a camera.
  • the film units incorporating the invention and comprising film pack 41 are adapted to; be employed in photo-graphic apparatus such as a hand-held camera 57, illustrated in FIGS. 6 through 9 of the drawings.
  • Camera 57 comprises a housing including a forward section 58 having a forward wall 59 with a recessed or reentrant section 60 and an aperture 61 in the reentrant section for transmitting light for exposing element 11 of a film pack positioned for exposure within the camera.
  • a hinged door 62 is provided for covering recessed section 60 and for mounting a lens and shutter assembly 63, the latter being connected to recessed section 60 by a collapsible bellows 64 secured at one end to the lens and shutter assembly and secured at its other end to the recessed section in surrounding relation to aperture 61, the former comprising an imagereversing optical system adapted to rectify geometric transfer image reversal which is resultant from exposure and processing of the film unit by reason of the units structural parameters.
  • the camera housing can be constructed in the form ofa camera back or film pack adaptor intended to be mounted on or coupled with a camera or other photographic exposure device.
  • the camera housing includes a rear section 65 having a rear wall 66 and side walls 67 cooperating with forward housing section 58 to provide a chamber 68 to the rear of forward wall 59 and aperture 61 for containing the film pack in position for exposure through aperture 61.
  • Film pack 41 is mounted within chamber 68 with the wall of the pack located against the rear surface of reentrant section 60 and with aperture 47 in the forward wall of the pack aligned with aperture 61.
  • Rear housing section 65 is preferably pivotably secured to forward housing section 58 adjacent one end of the housing, herein shown and designated for purposes of description as the upper end, by a hinge which permits the two housing sections to be moved apart from one another to allow loading of a film pack into chamber 68.
  • the camera housing includes a lower end wall comprising end wall 69 on forward housing section 58 and another end wall 70 on rear housing section 58.
  • a film withdrawal passage 71 is provided in lower end wall of the housing to permit withdrawal of a film unit from the housing.
  • Suitable latch means (not shown) of a conventional type are also provided in the lower portion of the housing for retaining the two housing sections together in the closed or operative position shown in the drawmgs.
  • Camera 57 includes a pair of juxtaposed pressureapplying members in the form of pressure-applying rolls 29 and 30 within chamber 68 adjacent film withdrawal passage 71.
  • Pressure-applying rolls 29 and 30 are mounted for pivotal movement with their axes substantially in a common plane, and resilient means are provided for biasing the rolls toward one another into juxtaposition so as to apply compressive pressure to a film unit during movement thereof between the rolls.
  • the pressure-applying rolls cooperate to form a convergent (and divergent) passage through which the film unit is moved for effecting the processing of the film unit, and this passage between the pressure-applying rolls is located in substantial alignment with withdrawal passage 71.
  • both rolls are mounted on rear housing section 65 so that when the housing sections are pivoted apart from one another, an assemblage of film units may be loaded into the camera with the leaders thereof extending from the camera past and to one side (forward) of the pressure applying rolls. Portions of end walls 69 and 70 cooperate to define an opening 82 between the forward and rear housing sections through which the leaders extend from the camera housing.
  • Camera 57 includes means for guiding the tapered end section of film unit 10 between pressure-applying rolls 29 and 30 in response to withdrawal movement of leader 55 past roll 29 to the front thereof and through opening 71.
  • this guide means comprises a guide bar 75 mounted on rear housing section 65 closely adjacent roll 29 and having a substantially straight guiding edge extending from side to side of the camera housing and lying substantially in a plane through the convergent passage between pressure-applying rolls 29 and 30, i.e., tangent to the rolls.
  • Section 76 of guide bar 75 comprising the forward edge of the guide bar is located with its forward edge approximately in line with the forwardmost portion of roll 29, and guide bar 75 may be provided with facing end surfaces spaced from one another by a distance slightly greater than the width of leader 55.
  • a guide plate 78 approximately equal in length to the width of leader 55, including facing end sections 79 spaced from one another by a distance slightly greater than the width of leader 55, is mounted on forward housing section 58, and extends toward the rear of the camera adjacent guide bar 75 at its forwardmost extremity 80.
  • the rearmost edge of guide plate: 78 may be curved, where desired.
  • Guide bar 75, facing end sections 79, and guide plate 78 cooperate with one another to define a guide passage extending generally in a direction toward end wall 70 of the camera and having a width, measured from side to side of the camera, just slightly greater than the width of leader 55, so that the leader may be moved through passage 81.
  • tapered end section 22, at the leading edge thereof, is wider than leader 55 so that tapered end section 22 is unable to enter passage 81.
  • Facing surfaces 79 of guide plate 78 function to guide tapered end section 22 of the film unit into the convergent passage between pressureapplying rolls 29 and 30.
  • the forward and rear housing sections are pivoted apart from one another and a film pack 41 is positioned within the forward housing section 58 with the forward wall 43 of pack 41 resting against section of the forward wall 59 of forward housing section 58, and with leaders 55 and leader 108 projecting from the pack extending across and to the rear of guide plate 78 and end wall 69.
  • Rear housing section is then pivoted into the operative position shown, causing the intermediate section 82 of guide bar 75 to engage the leaders displacing them forwardly so that they extend. through passage 81 toward the forward wall of the camera, past pressureapplying roll 29 and through opening 82 in end walls 69 and 70.
  • the tapered end section is withdrawn from the pack and, being unable to enter passage 81, is guided by the guide bar, guide members and guide plate into the convergent passage between the pressure-applying rolls.
  • Film withdrawal passage 71 in the lower end wall of the camera housing, is at least equal in width to the width of the film unit, whereas passage 81 need be of a width only sufficient to allow the passage of leaders 55. It is desirable to allow only one leader at a time to project from the camera where the leader may be grasped; and this is desirable to prevent the operator from accidentally pulling the wrong leader, or pulling more than one leader at a time.
  • end wall 70 is provided with a recess, designated 84, adjacent passage 81 for holding the leading end sections of leaders 55.
  • leading end sections, designated 85, of leaders 55 are folded back upon themselves and each leading end section is detachably adhered to the leader of the preceding film unit, with the leading end section 85 of the first (to be exposed) film unit being attached to leader 56.
  • the folded leading end sections 85 of leaders 55 are contained within recess 84 which is provided with a deplaceable guide bar element 75. As leader 56 or a leader 55 is withdrawn through opening 71, the the leader is attached to the tapered end section and results in separation of the leader at these areas.
  • leader 55 is pulled from the camera advancing tapered end section 22 and tapered end portion 23 between pressure-applying rolls 29 and 30 to the position shown in FIG. 7 at which leader 55 extends from its point of attachment to tapered end section 22 at almost a right angle from the plane of the tapered end section.
  • the leading end of tapered end section 22 projects through passage 71 a sufficient distance to permit the tapered end section to be grasped, and the application of a continued pulling force on leader 55 results in the exertion of a shearing force to leader 55 at the areas where it is secured to the surfaces of photosensitive element 11 and image-receptive element 16.
  • trailing end section 27 of sheet 18 and trailing end section 25 of sheet 11 may be secured together by positive engaging means adapted to insure retention of processing composition overrun disposed intermediate the sections thus preventing escape external the film unit boundaries.
  • the positive engaging means employed should be simple and inexpensive to fabricate, so that it does not add appreciably to the cost of the film unit, and it should be easy to assemble and employ in order to contribute in a practical manner to the efiicient operation of the film unit, and film pack and camera employing same.
  • engaging or lock closure means mention may be made of moisture sensitive adhesives activatable upon contact with the fluid processing composition; self-adhering adhesives coated on the trailing prospectively opposed surface of each sheet element; and engaging members such as shaped, extruded plastic interlocking elements having a pluality of, preferably resilient, interlocking tongues and grooves mounted on the distal opposed surfaces of each sheet element; a male engaging member mounted on the distal surface of one sheet element and a female engaging member mounted on the distal prospectively opposed surface of the other sheet element and may comprise, respectively, tongue and groove or ball and socket construction, and preferably possesses at least one resilient component member adapted for frictional retention upon engagement with the second member; a plurality of polymeric hooks, for example, nylon hooks, positioned on the trailing edge of one sheet element and a plurality of filamentary loops on the trailing edge of the second sheet element such as the closure materials sold by Velcro Corporation, Manchester, NH. etc.
  • the engaging means may extend, in whole or in part, in continuous or discontinuous fashion, lengthwise the trailing edge of edges retaining same.
  • the means for interposing the processing composition selected intermediate the reception layer and the silver halide layer comprises a rupturable container retaining a processing composition comprising the solvent and pH concentrations required fixedly positioned and extending transverse a leading edge section of the sheet elements to effect, upon application of compressive pressure, discharge of the processing composition intermediate the reception layer and the photosensitive silver halide layer next adjacent.
  • the opacifying agent is preferably disposed within the processing composition, as retained in the rupturable container, for distribution as a component of such composition intermediate the reception and silver halide layers, subsequent to selective exposure of the film unit.
  • Multicolor images may be obtained using color image-forming components in the diffusion transfer process of the present invention by several techniques.
  • obtaining multicolor transfer images utilizing, for example, dye developers as dye image-providing materials by employment of an integral multilayer photosensitive element, such as is disclosed in aforementioned U. S. Pat. No. 2,983,606 wherein at least two selectively sensitized photosensitive strata, superposed on a single support, are processed, simultaneously and without separation, with a single, common image-receiving layer.
  • a suitable arrangement of this type comprises the opaque support carrying a red-sensitive silver halide stratum, a greensensitive silver halide stratum and a blue-sensitive silver halide 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 stratum, for example, in the form of particles, or it may be employed as a layer behind the appropriate silver halide strata.
  • Each set of silver halide strata 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.
  • a yellow filter in front of the green-sensitive emulsion and such yellow filter may be incorporated in an interlayer.
  • a yellow dye developer of the appropriate sepectral characteristics and present in a state capable of functioning as a yellow filter may be employed.
  • a separate yellow filter may be omitted.
  • the film unit is specifically adapted to provide for the production of a multicolor dye transfer image and the photosensitive laminate comprises, in order of essential layers, the dimensionally stable opaque layer; at least two selectively sensitized silver halide strata each having dye image-providing material .of predetermined color associated therewith, for example, dye developers asdetailed above, which are soluble and diffusible in processing composition as a function of the point-topoint degree of exposure of the respective associated silver halide stratum.
  • the imagereceptive sheet element will be a polymeric layer dyeable by the dye image-providing materials and a dimensionally stable transparent layer.
  • the preferred dye imageproviding materials comprise dyes which are silver halide developing agents, as stated above, for purposes of simplicity and clarity, the present invention will be further 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 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.
  • the dye developers are preferably selected for their ability to provide colorsthat 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 silve halide stratum.
  • the dye developer may, for example, be in a coating or layer behind the respective silver halide stratum and such a layer of dye developer may be applied byuse 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, polyvinyl alcohol, and the like, adapted to be permeated bythe chosen diffusion transfer fluid processing composition.
  • the silver halide strata 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,
  • each of the silver halide strata, and its associated dye is separated from the remaining strata, and their associated dye, by separate alkaline solution permeable polymeric interlayers.
  • the silver halide strata comprises photosensitive silver halide dispersed in gelatin and are about 0.6 to 6 microns in thickness; the dye itself is dispersed in an aqueous alkaline solution permeable polymeric binder, preferably gelatin, as a separate layer about I to 7 microns in thickness; the alkaline solution permeable polymeric interlayers, preferably gelatin, are about 1 to 5 microns in thickness; the 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 developerlred-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 unitintermediate those units, recognizing that the relative order of such units may be varied in accordance with the desires of the operator.
  • FIG. 5 there is shown a diagrammatic enlarged cross-sectional view of sheet elements 11 and 18 constructed in accordance with the present invention.
  • the film unit is shown to specifically comprise with respect to sheet element 11 a photosensitive laminate including, in order, dimensionally stable opaque layer 91, preferably an actinic radiationopaque flexible sheet material; cyan dye developer layer 92; red-sensitive silver halide emulsion layer 93; interlayer 94; magenta dye developer layer95; greensensitive silver halide emulsion layer 96; interlayer 97; yellow dye developer layer 98; blue-sensitive silver halide emulsion layer 99; auxiliary layer 100, which may contain an auxiliary silver halide developing agent.
  • opaque layer 91 preferably an actinic radiationopaque flexible sheet material
  • cyan dye developer layer 92 red-sensitive silver halide emulsion layer 93; interlayer 94; magenta dye developer layer95; greensensitive silver halide emulsion layer 96; interlayer 97; yellow dye
  • Image-receptive sheet laminate 101 is shown to comprise, in order, opaque layer 102; reflection layer 103; imagereceiving layer 104; spacer layer 105; neutralizing layer 106; and dimensionally stable transparent layer 107, preferably an actinic radiation transmissive flexible sheet material.
  • the fluid contents of the container preferably comprise an aqueous alkaline solution having a pH and solvent concentration at which the dye developers are soluble and diffusible and contains an opacifying agent preferably in a quantity sufficient, upon distribution, effective to provide a layer exhibiting optical transmission density 6.0 to prevent exposure of photosensitive silver halide emulsion layers 93, 96 and 99 by actinic radiation incident on dimensionally stable transparent layer 107 during processing in the presence of such radiation and to afford immediate viewing of dye image formation in image-receiving layer 104 during and subsequent to dye transfer image formation.
  • an opacifying agent preferably in a quantity sufficient, upon distribution, effective to provide a layer exhibiting optical transmission density 6.0 to prevent exposure of photosensitive silver halide emulsion layers 93, 96 and 99 by actinic radiation incident on dimensionally stable transparent layer 107 during processing in the presence of such radiation and to afford immediate viewing of dye image formation in image-receiving layer 104 during and subsequent to dye transfer image formation.
  • 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 laminate are appropriately protected from incident radiation, at one major surface of the opaque layer 102 and at the remaining major surface by the dimensionally stable opaque layer 91.
  • the selected reflecting agent providing reflecting layer 103 should be one providing image formed in the dyeable polymeric layer.
  • a reflecting agent be selected that will not interfere 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 reflecting agents will comprise pigments 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.
  • reflecting pigments adapted for employment in the practice of the present invention, mention may be made of barium sulfate, zinc sulfide, titanium dioxide, barium stearate, silver flake, silicates, alumina, zirconium oxides, zirconium acetyl acetate, sodium zirconium sulfate, kaolin, mica, and the like.
  • a particularly preferred reflecting agent comprises titanium dioxide due to its highly effective reflection properties.
  • titanium dioxide will be present in a concentration effective to provide a percent reflectance of 85 will be coated at a coverage of 200 to 1,000 mgs./ft. to provide the reflecting layer.
  • the reflecting agents to be employed are those which remain substantially immobile within their respective compositions during and subsequent to photographic processing and particularly those which comprise insoluble and nondiffusible inorganic pigment dispersions within the layer in which they are disposed.
  • reflecting agent pigment may thus be distributed in whole or in part within a processing composition permeable polymeric matrix such as gelatin and/or any other such polymeric matrixes as are specifically denoted throughout the specification as suitable for employment as a matrix binder and may be distributed in one or more of the film unit layers which may be separated or contiguous, opposite the imagereceiving layer from the transparent support, provided that its distribution and concentration is effective to provide the denoted post processing masking function.
  • a processing composition permeable polymeric matrix such as gelatin and/or any other such polymeric matrixes as are specifically denoted throughout the specification as suitable for employment as a matrix binder and may be distributed in one or more of the film unit layers which may be separated or contiguous, opposite the imagereceiving layer from the transparent support, provided that its distribution and concentration is effective to provide the denoted post processing masking function.
  • the opacifying agent selected should be one exhibiting maximum spectral absorption of radiation at the wavelengths to which the film units photosensitive silver halide layer or layers are sensitive and should be substantially immobile or nondiffusible during performance of its radiation filtration function, in order to maintain and enhance the optical integrity of the dispersion as a radiation filter unit functioning in accordance with the present invention, and to prevent its diffusion into and localized concentration within the reflection and/or image-receiving layer thereby decreasing the efiiciency of the reflecting pigment dispersion as a background against which image formation may be immediately viewed, during and subsequent to the initial stages in the diffusion transfer processing of the film unit.
  • the opacifying agent selected may comprise one or more filter materials possessing absorption complementary to such silver halide layers in order to provide effective protection against physical fog providing radiation during processing and the selected agents should be those exhibiting major spectral absorption during transfer image formation and will be preferably selected for employment in the minimum concentration necessary to provide an optical transmission density 6.0, at wavelengths at which the silver halide layer is maximally responsive.
  • Preferred opacifying agent or agents will possess the maximum opacifying capacity per unit weight, be photographically nondelterious and substantially nondiffusible during and subsequent to distribution of the processing composition which may contain the same.
  • a particularly preferred opacifying agent has been found to comprise carbon black due to its highly efficient absorption characteristics.
  • a processing composition particularly desired for employment in the letter identified embodiment will contain carbon black in a concentration effective, e.g., about 3 to 6 grams of carbon black dispersed in 100 cc. of water, to prevent transmission, through the distributed stratum comprising the composition, of in excess of percent of the actinic radiation incident on the stratum.
  • preferred agents are those which remain immobile within their respective compositions during the subsequent to photographic processing and particularly those which comprise insoluble and nondiffusible materials.
  • the liquid processing composition referred to for effecting multicolor diffusion transfer processes comprises at least 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-forming material of the type which, when the composition is spread and dried, forms a relatively firm and relatively stable film.
  • the preferred 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 filmforming material is preferably contained in the processing composition in such suitable quantities as to impart to the composition a viscosity in excess of 100 cps. at a temperature of approximately 24 C. and preferably in the order of 100,000 cps. to 200,000 cps. at that temperature.
  • 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 90, incident on the laminates exposure surface.
  • film unit is processed by being passed through opposed suitably gapped rolls 29 and 30 in order to apply compressive pressure to frangible container 21 and to effect rupture of longitudinal seal 32 and distribution of alkaline processing composition 39, optionally possessing an inorganic opacifying pigment and a pH at which the cyan, magenta and yellow dye developers are soluble and diffusible as a function of the point-to-point degree of exposure of redsensitive silver halide emulsion layer 93, greensensitive silver halide emulsion layer 96 and bluesensitive silver halide emulsion layer 99, respectively, intermediate auxiliary layer 100 and image-receiving laminate 101.
  • Alkaline processing composition 39 permeates emulsion layers 93, 96 and 99 to initiate development of the latent images contained in the respective emulsions.
  • the cyan, magenta and yellow dye developers, of layers 92, 95 and 98, 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 diffusible cyan, magenta and yellow dye developer, as a function of the point-to-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 dyeable polymeric layer 104 to provide a multicolor dye transfer image to that layer which is viewable against the background provided by the reflecting layer 103 masking cyan, magenta and yellow dye developer remaining associated with blue-sensitive emulsion layer 99, greensensitive emulsion layer 96 and red-sensitive emulsion layer 93.
  • a sufficient portion of the ions comprising aqueous alkaline processing composition 39 transfer, by diffusion, through permeable polymeric reception layer 104, permeable spacer layer 105 to polymeric neutralizing layer 106 whereby the environmental pH of the system decreases as a function of neutralization to a pH at which the cyan, magenta and yellow dye developers, in the reduced form, are substantially nondiffusible to thereby provide a stable multicolor dye transfer image.
  • the alkaline solution component of the processing composition positioned intermediate the photosensitive element and the image-receiving layer, thus permeates the emulsions to initiate development of the latent images contained therein.
  • the respective associated dye developers are mobilized in unexposed areas as a consequence of the development of the latent images. This mobilization is apparently, at least in part, due to a change in the solubility characteristics of dye developer upon oxidation and especially. as regards to 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 associated dye developer is diffusible and thus provides an imagewise distribution of unoxidized dye developer dissolved in the liquid processing composition, as a function of the pointto-point degree of exposure of the silver halide emulsion. At least part of this imagewisedistribution 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.
  • leading end sections 20 and 23 including container 31 may be manually dissociated from the remainder of the film unit, as described above.
  • Photosensitive sheet elements similar to that shown in the drawings may be prepared, for example, by coating, in succession, on a gelatin subbed, 5 mil. opaque cellulose triacetate film base, the following layers:
  • Image-receiving sheet elements may be constructed by coating a transparent 5 mil. cellulose triacetate film base, in succession, with the following illustrative layers:
  • 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:
  • the photosensitive composite film units may be exposed and processed by passage of the exposed film units through appropriate pressure-applying members, such as suitably gapped, opposed rolls, to effect rupture of the containerand distribution of its contents.
  • the multicolor dye transfer image formation may be viewed through the transparent cellulose triacetate layer against the titanium dioxide reflecting layer backgroun. Multicolor dye transfer image formation will be found to be substantially completed and exhibiting the required color brilliance, hues, saturation and isolation, with a period of approximately 90 seconds.
  • the image formation may be immediately viewed upon distribution of the processing composition by reason of the protection against incident radiation afforded the photosensitive silver halide emulsion layers by the compositions optical transmission density of -6.0 density units and against the titanium dioxides effective reflective background.
  • the pH and solvent concentration of the alkaline processing solution initially employed must possess a pH at which the dye developers employed are soluble and diffusible. Although it has been found that the specific pH to be employed maybe readily determined empirically for any dye developer and optical filter agent,
  • 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 provide maintenance of the spread composition as a structurally stable layer of the laminate, subsequent to distribution, it is not necessary that such agent be employed as a component of the composition.
  • Neutralizing means for example, a polymeric acid layer of the type discussed above will be 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 below the pKa of the agent at which the dyes are substantially nondifiusible, in order to advantageously further stabilize and optimize reflectively of the dye transfer image.
  • the neutralizing layer may comprise particulate acid reacting reagent disposed within the film unit or a polymeric acid layer, for example, a polymeric acid layer approximating 0.3 to 1.5 mils.
  • the film unit may also contain a polymeric spacer or barrier layer, for example, approximately 0.1 to 0.7 mil. in thickness, next adjacent the polymeric acid layer, opposite the respective support layer, as previously described.
  • the film units may employ the presence of a polymeric acid layer such as, for example, of the type set forth in U. S. Pat. No. 3,362,819 which, most preferably, includes the presence of an inert timing or spacer layer intermediate the polymeric acid layer carried on a support and the image-receiving layer.
  • a polymeric acid layer such as, for example, of the type set forth in U. S. Pat. No. 3,362,819 which, most preferably, includes the presence of an inert timing or spacer layer intermediate the polymeric acid layer carried on a support and the image-receiving layer.
  • the polymeric acid layer may comprise polymers which contain acid groups, such as carboxylic acid and sulfonic acid groups, which 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 acid-reacting group is, of course, retained in the polymer layer.
  • the 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 hydro gen phthalate; polyvinyl acetate hydrogen phthalate; polyacrylic acid; acetals of polyvinyl alcohol with carboxy or sulfo substituted aldehydes, tag, m-, or pbenzaldehyde sulfonic acid or carboxylic acid
  • the pH of the processing composition preferably is of the order of at least 12 to 14 and the pKa of the selected optical filter agents will accordingly preferably be in the order of 13 or greater.
  • the polymer layer is disclosed to contain at least sufficient acid groups to effect a reduction in the pH of the image receiving layer from a pH of about 12 to 14 to a pH of at least 1 l 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 polymeric 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 receiving layer must be kept at a functional transfer level, for example, 12 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 1 l 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 diffusion 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 receiving 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 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 polymer layer may be effected by mixing acid polymer with a polymer free of acid groups, or lower in concentration of acid groups, and compatible therewith, or by using only an 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 strengthand when neces sary or desirable, suitable subcoats are employed to help the various polymeric layers adhere to each other during storage and use. I
  • the inert spacer layer of the last-mentioned patent acts to time control the pH reduction by the polymeric acid layer. This timing is dis closed 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-diffuses through the spacer layer.
  • the aforementioned 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 80 F., a premature decrease in the pH of the transfer processing composition occurs due, at least in part, to the rapid diffusion 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 80 F.
  • the lastmentioned 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 1,000, preferably of about 1,000 to 50,000, possessing a degree of acetalation within about to 30 percent, 10 to 30 percent, to 80 percent, and 10 tp 40 percent, of the polyvinyl alcohols theoretical polymeric hydroxy groups, respectively, and including mixed acetals where desired.
  • a mixture of the polymers may be employed, for example, a mixture of hydroxypropyl methyl cellulose and partial polyvinyl butyral.
  • the detailed and preferred film units of the present invention specifically provides for the production of a highly stable transfer image accomplished, at least in part, by in-process adjustment of the environmental pH concentration from a pH concentration at which dye transfer is inoperative subsequent to substantial transfer image formation.
  • the stable color transfer image is obtained irrespective of the fact that the film unit is maintained as an integral laminate unit during processing, viewing and storage of the reflection print.
  • the multicolor transfer images may be provided over an extended processing temperature range which exhibit desired maximum and minimum dye transfer image densities; yellow, magenta and cyan dye saturation; red, green and blue hues; and color separation and customer utilization of the unit.
  • 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, acetate-propionate, or acetatebutyrate; alkaline solution impermeable, water vapor permeable papers; crosslinked 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, nit
  • 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 U. S. Pat. No. 3,148,061, issued Sept. 8, 1964.
  • liquid processing composition employed may contain an auxiliary or accelerating developing agent, such as p-methylaminophenol, 2,4- diamino-phenol, p-benzylaminophenyl, 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 p-benzylaminophenol and l-phenyl- 3-pyrazolidone in combination with 2,5-bisethylenimino-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, 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 energytransfer reaction, with the oxidation product of an oxidized auxiliary developing agent, the latter developing agent being oxidized by the development of exposure silver halide.
  • a reaction e.g., an energytransfer reaction
  • 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,[-3- unsaturated carboxamides and copoly-mers of N-alkyl-a,B-carboxamides with N-hydroxyalkyl-a,B- unsaturated carboxamides as disclosed in U. S. Pat. No.
  • the preparation of the dye developer dis persion 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 differential 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.
  • dye image-forming materials wherein color diffusion transfer processes are described which employ color coupling techniques ,comprising, at least in part, reacting one or more color developing agents and one or more color formers or couplers to provide a dye transfer image to a superposed image-receiving layer wherein color diffusion transfer processes are described which employ the imagewise differential transfer of complete dyes by the mechanisms therein described to provide a transfer dye image to a contiguous image-receiving layer, and thus including the employment of image-providing materials in whole or in part initially insoluble or nondiffusible as disposed in the film unit which diffuse during processing as a direct or indirect function of exposure.
  • 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 water-soluble salts 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 U.
  • 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, silver chloroiodobromide 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, silver chloroiodobromide or silver iodobromide, of varying halide ratios and varying silver concentrations.
  • 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 a 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 silver halide emulsions employed will be emulsions adapted to provide a Diffusion Transfer Process Exposure Index 50, which Index indicates the correct exposure rating of a diffusion transfer color process at which an exposure meter, calibrated to the ASA Exposure Index, must be set in order that it give correct exposure data for producing color transfer prints of satisfactorily high quality.
  • the Diffusion Transfer Process Exposure Index is based on a characteristic l-I&D curve relating original exposure of the photosensitive silver halide emulsions to the respective curve densities forming the resultant transfer image.
  • the Diffusion Transfer Exposure Index is based on the exposure to which the photosensitive silvelr halide emulsions, for use in color diffusion transfer. processes, must be subjected in order to obtain an acceptable color transfer image by that process and is a direct guide to the exposure setting to be entered in a camera in order to obtain proper exposure of the film uhit.
  • the photosensitve 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 photosensitve 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 m'inute red-sensitized emulsion elements, minute greensensitized emulsion elements and minute jbluesensitized 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 image-carrying layer as being reversed, in the positive-negative sense, with respect to the image in the photosensitive emulsion layers.
  • the expression positive image 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 image-carrying 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 a geometrically reversed image of the subject. Accordingly, to provide transfer image formation geometrically nonreversed, exposure of such film unit must be accomplished through 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-forming 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-forming component retaining layer and the dimensionally stable opaque layer.
  • a photographic film unit for the production of a color photographic reflection print by diffusion transfer processing and adapted to be processed subsequent to photo-exposure by passage intermediate a pair of juxtaposed pressure-applying members which film unit comprises first and second sheet elements affixed transverse a leading end section, said first sheet'comprising an opaque support carrying on one surface photosensitive silver halide having associated therewith a diffusion transfer process dye image-providing material, said second sheet comprising a transparent support carrying on one surface, in order, a diffusion transfer image-receiving layer and a dye image-providing material permeable reflecting layer, at least one of said first and second sheets additionally carrying on the surface of said sheet intermediate the leading edge of said first sheet and said second sheet rupturable container means retaining a fluid processing composition for distribution intermediate said first and second sheets upon application of pressure to said container means, said second sheet adapted to be superposed contiguous the surface of said first sheet with said photosensitive silver halide and said reflecting layer intermediate said opaque and said transparent supports and an opacifying agent
  • a photographic film unit as defined in claim 3 including a sheet element affixed at its trailing end section to a leading end section of one of said first and second sheet elements.
  • said dye image-providing material comprises a dye which is a silver halide developing agent soluble and diffusible in an aqueous alkaline processing composition at the first pH and substantially nondiffusible at a second pH lower than the first pH and said means for converting said pH of said film unit are adapted to reduce said processing composition from said first pH to said second pH subsequent to substantial dye transfer image formation.
  • a photographic film unit as defined in claim 1 including, carried on said opaque support, at least two selectively sensitized silver halide layers each having a dye image-providing material adapted to provide dye image predetermined color as a function of the photoexposure of its silver halide layer.
  • each of the selectively sensitized silver halide emulsion layers possesses predominant spectral sensitivity to separate regions of the spectrum and the dye image-providing material associated with each of said silver halide emulsion layers is adapted to provide a dye transfer image possessing a spectral absorption range subsequent to processing substantially complementary to the predominant sensitivity image of its associated emulsion layer.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
  • Photographic Developing Apparatuses (AREA)
  • Structure And Mechanism Of Cameras (AREA)
US00191941A 1971-10-22 1971-10-22 Photographic products comprising an opacifying agent in association with a reflecting agent Expired - Lifetime US3778271A (en)

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JP (1) JPS5729695B2 (enrdf_load_stackoverflow)
CA (1) CA992787A (enrdf_load_stackoverflow)
DE (1) DE2250350C2 (enrdf_load_stackoverflow)
FR (1) FR2156894A1 (enrdf_load_stackoverflow)
GB (1) GB1408060A (enrdf_load_stackoverflow)
IT (1) IT966446B (enrdf_load_stackoverflow)

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US3907563A (en) * 1973-12-13 1975-09-23 Polaroid Corp Diffusion transfer process using processing composition impregnated image-receiving element
US4154610A (en) * 1974-10-31 1979-05-15 Fuji Photo Film Co., Ltd. Photographic method and film unit
US4546061A (en) * 1983-11-01 1985-10-08 Fuji Photo Film Co., Ltd. Film unit for instant camera

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0455995U (enrdf_load_stackoverflow) * 1990-09-21 1992-05-13

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US3415645A (en) * 1967-03-10 1968-12-10 Polaroid Corp Opaque permeable polymeric layer in photo-sensitive element
US3647437A (en) * 1970-12-18 1972-03-07 Polaroid Corp Photographic products, processes and compositions

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US2983606A (en) * 1958-07-14 1961-05-09 Polaroid Corp Processes and products for forming photographic images in color
US3080805A (en) * 1961-05-26 1963-03-12 Polaroid Corp Photographic apparatus
US3598591A (en) * 1967-06-09 1971-08-10 Eastman Kodak Co Photographic element containing readily removable opaque protective layers
US3473925A (en) * 1968-05-23 1969-10-21 Polaroid Corp Photographic diffusion transfer color process and film unit for use therein
BE757959A (fr) * 1969-10-24 1971-04-23 Eastman Kodak Co Produit pour la mise en oeuvre d'un procede de photographie en couleurspar diffusion-transfert
GB1336361A (en) * 1970-01-19 1973-11-07 Polaroid Corp Photographic silver halide products and diffusion transfer processes

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Publication number Priority date Publication date Assignee Title
US3415645A (en) * 1967-03-10 1968-12-10 Polaroid Corp Opaque permeable polymeric layer in photo-sensitive element
US3647437A (en) * 1970-12-18 1972-03-07 Polaroid Corp Photographic products, processes and compositions

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3907563A (en) * 1973-12-13 1975-09-23 Polaroid Corp Diffusion transfer process using processing composition impregnated image-receiving element
US4154610A (en) * 1974-10-31 1979-05-15 Fuji Photo Film Co., Ltd. Photographic method and film unit
US4546061A (en) * 1983-11-01 1985-10-08 Fuji Photo Film Co., Ltd. Film unit for instant camera

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JPS5729695B2 (enrdf_load_stackoverflow) 1982-06-24
FR2156894A1 (enrdf_load_stackoverflow) 1973-06-01
JPS4876532A (enrdf_load_stackoverflow) 1973-10-15
CA992787A (en) 1976-07-13
IT966446B (it) 1974-02-11
DE2250350C2 (de) 1982-12-23
DE2250350A1 (de) 1973-04-26
GB1408060A (en) 1975-10-01

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