US3694206A - Photographic film unit - Google Patents

Photographic film unit Download PDF

Info

Publication number
US3694206A
US3694206A US102447A US3694206DA US3694206A US 3694206 A US3694206 A US 3694206A US 102447 A US102447 A US 102447A US 3694206D A US3694206D A US 3694206DA US 3694206 A US3694206 A US 3694206A
Authority
US
United States
Prior art keywords
image
layer
sheet
sheets
film unit
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
US102447A
Other languages
English (en)
Inventor
Rogers B Downey
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 US3694206A publication Critical patent/US3694206A/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
    • G03C8/44—Integral units, i.e. the image-forming section not being separated from the image-receiving section
    • G03C8/46—Integral units, i.e. the image-forming section not being separated from the image-receiving section characterised by the trapping means or gas releasing means

Definitions

  • FIG. 2 PHOTOGRAPHIC FILM UNIT Filed Dec, 29, 1970 50 M i f f" FIG. 2
  • a photosensitive image-recording layer and an image-receptive layer are sandwiched between the sheets, preferably with the image-receptive layer closest the transparent sheet.
  • a container of a liquid processing agent adapted to initiate formation of a visible transfer image in the image-receptive layer when distributed between the sheets for permeation into the photosensitive layer following exposure thereof, is coupled to the sheets at the other end edge of the smaller sheet so as to dispense its liquid contents between the sheets in response to the application of compressive pressure.
  • a masking layer including a reflective pigment carried in a binder is coated or the side of the transparent sheet facing the smaller sheet and extends to the edges of the transparent sheet.
  • the masking layer is formed with a rectangular opening smaller than the smaller sheet and is located between the photosensitive and image-recording layers or between the latter and the transparent sheet to provide a reflective border surrounding the visible image formed in the image-recording layer.
  • the sheets and layers of the film unit may be laminated to one another to form an integral unit or the two support sheets and the layers carried thereon may be secured to one another only at their margins.
  • a number of U.S. patents disclose and/or claim the structure of self-developing film unit particularly adapted to the production of images in full color by processes involving diffusion transfer. Such patents include, for example, Nos. 3,415,644, 3,415,645, 3,415,646, and 3,460,452.
  • film units of this type include a pair of rectangular support sheets, at least one of which is transparent, coated on their facing surfaces with a plurality of layers including a photo-sensitive imagerecording layer and an image-receptive layer for supporting a visible transfer image.
  • the two support sheets are of equal width and are secured in face-to-face relation with the photosensitive and image-receptive layers sandwiched therebetween, by binding means including a binding sheet secured around and to the outer surfaces of the support sheets at their lateral margins and at one end margin.
  • the support sheets and the layers carried thereby also may be laminated to one another throughout the extent of their facing surfaces to form an integral unit.
  • Attached to the other end of the support sheets is a container of a liquid processing composition adapted to form a transfer image visible through the transparent support sheet when distributed between the support sheets for permeation into the photoexposed photo-sensitive, imagerecording layer.
  • the binding sheets and/ or binding strips are employed to form a seal between the container and the support sheets for conducting the processing liquid from the container between the support sheets in response to the application of compressive pressure to the container.
  • Processing of such a film unit is accomplished by advancing the film unit, container foremost, between a pair of pressure applying members which dispense the processing liquid from the container and distribute it between the sheets toward the opposite or trailing ends thereof.
  • the sheets of the film unit are retained in superposed relation following competion of processing and image formation so that the image formed between the sheets is protectively enclosed and is viewed through the transparent sheet.
  • the only processing step is distribution of the processing liquid within the film unit, and there is no necessity for subsequent processing and handling steps such as separation of the sheets nor are there any waste materials to be disposed of because all components of the film units remain together as a unit prior to, during and subsequent to processing.
  • the transparent sheet is longer than the other sheet and the rupturable container of processing liquid is mounted on an extended end section of the transparent sheet adjacent an edge of the other sheet.
  • the binding means include an external binding sheet which is generally rectangular and has a rectangular exposure and viewing opening therein.
  • This binding sheet is secured in covering relation to the entire outer surface of the transparent sheet, except of course in the region of the exposure and viewing opening, and the margins of the binding sheet are folded around at least the lateral edges and one (trailing) end edge of the support sheets and secured to the margins of the other support sheet.
  • the binding sheet performs a multiplicity of functions including retaining the support sheets in face-to-face relation; providing an attractive border or frame surrounding the image; assisting in the distribution of the processing liquid by controlling the spacing between the pressure-applying members which distribute the processing liquid; preventing admission of air between the sheets, at least at their lateral margins; and providing means for trapping and retaining excess processing liquid.
  • the binding sheet performs a number of functions as a part of the film structure includmg:
  • the binding sheet performs still another important function in the film manufacturing and assembly process.
  • the binding sheet is supplied as an elongated web which functions as a carrier on which other components of the film unit are mounted and attached during the assembly process as the web moves through the assembly apparatus.
  • the binding sheet Because the functions performed by the binding sheet are important and often critical to assembly, processing and the appearance of the product, the physical specifications for this sheet are equally important and critical necessitating the use of a relatively expensive material representing a substantial fraction of the overall cost of each film unit. However, it will also be apparent that a major portion of this cost, e.g. 80%, represents waste, namely the material cut out of the binding sheet to form the relatively large exposure opening therein.
  • Objectives of the present invention include the provision of a novel and improved self-developing film of the general type described comprising structure for performing all of the functions of the binder s'heet while eliminating the binder sheet itself.
  • This film unit will function in essentially the same manner and can be processed by the same apparatus to produce a more pleasing product (photographic print) while offering a number of cost-saving advantages in manufacture and assembly.
  • the objective of cost saving is achieved not only by eliminating the binding sheet and employing less expensive means for securing the sheets to one another, but by utilizing improvements in manufacturing and assembly techniques made possible by the novel structure and by providing a structure in Which one of the sheets is narrower as well as shorter than the other sheet.
  • both support sheets and the layers carried thereon have been of unequal length and of equal width.
  • the shorter sheet includes the photosensitive image-recording layer which, in the case of a film unit designed to produce color images such as described in the aforementioned patents, comprises a multiplicity of strata including differently sensitized silver halide strata and associated dye developer strata.
  • the shorter sheet constitutes a relatively complex and expensive structure and its cost per unit area is large relative to the cost of the longer sheet so that the shorter sheet represents a large proportion of the total cost of each film unit. Accordingly, a substantial cost saving can be realized by further reducing the area of the more expensive sheet to a minimum, specifically, by making it as narrow as possible in addition to making it as short as possible.
  • the sheet which costs the most per unit area is both narrower and shorter than the less expensive sheet which, in this case, is the transparent sheet.
  • the transparent sheet may serve merely to aid in the distribution of the processing liquid in contact with another sheet carrying all of the layers involved in the image-forming process.
  • photographic transfer prints are usually surrounded by an image-free border having sharply defined inner edges.
  • This border is uniformly wide and in the case of prior art film units of the type described, is provided by marginal portions of the binding sheet; paper, polymers, or composites thereof being suitable for this purpose.
  • the binding sheet providing the border is attached to the exterior of the transparent support sheet through which the image is viewed and accordingly, is subjected to physical damage as Well as becoming marred or discolored.
  • Another function of the border provided by the binding sheet is to mask any image formed between the sheets outside of the area in which the image-forming exposure is made.
  • the present invention contemplates an improvement over this structure in that the material which forms the combined mask and border is located within the film unit between the sheets so that the forward surface of the photographic print is a plain, smooth surface without attachments or discontinuities and the image is surrounded by a plain border which cannot be physically damaged or discolored.
  • the improved structure for securing the sheets to one another at their margins makes this possible and the border or mask is formed as a layer on the inner surface of the transparent sheet so that there is no waste material as in the case where an exposure aperture is formed in a sheet by cutting out a relatively large section thereof.
  • the invention accordingly comprises the product possessing the features, properties and the relation of components 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, partially in section, illus trating a photographic film unit embodying the invention
  • FIG. 2 is a fragmentary, sectional view taken along the line 22 of FIG. 1;
  • FIG. 3 is a perspective view showing the film unit partially in section, illustrating the processing of the film unit.
  • the present invention is primarily concerned with the physical aspects or structure of a photographic, self-developing film unit adapted to incorporate a variety of diffusion transfer systems for producing visible images.
  • This film unit is particularly adapted for incorporating diffusion transfer systems capable of forming full color images which rely for color image formation upon a differential in mobility or solubility of a dye image-providing material achieved as a function of development of a photosensitive, image-recording material such as silver halide, so as to provide an imagewise distribution of the dye image-providing material which is diffusible and is selectively transferred, at least in part, by diffusion to a superposed dyeable, image-receptive stratum to impart thereto, the desired transfer image.
  • the basic components of a multicolor image-forming system of this type include a photosensitive layer comprising a plurality of selectively sensitized silver halide strata each having associated therewith a dye image-providing material exhibiting desired spectral absorption characteristics.
  • Most commonly employed photosensitive layers of this type are the so-called tripack structures employing blue-, greenand red-sensitive silver halide emulsions having associated therewith, respectively, yellow, magenta and cyan dye image-providing materials.
  • the image-receptive layer may comprise any of the dyeable materials heretofore known in the photographic art for supporting color transfer images including dyeable polymers such as gelatin, polyvinyl alcohol or gelatin containing a dye mordant.
  • dyeable polymers such as gelatin, polyvinyl alcohol or gelatin containing a dye mordant.
  • Such layers are designed to receive the imagewise distribution of diffused, dye image-providing material and are described in detail in many of the above-mentioned patents including 3,227,550.
  • the image-forming system will also contain additional layers or strata for performing a variety of functions including arresting or restraining development, particularly in the dyeable stratum or in an associated layer, and especially in integral or composite structures in which the layers including the photosensitive and image-receptive layers are retained together as a unit without separation.
  • the film unit contains means for providing a reflecting layer between the photosensitive layer and the dyeable image-receptive layer so as to effectively mask the photosensitive layer and provide a background for viewing, by reflected light, the dye image formed on the overlying dyeable stratum.
  • Such means for providing a reflecting layer between the overlying photosensitive and image-receptive layers may take a number of different forms.
  • a suitable reflecting agent may be incorporated in a liquid processing composition adapted to be distributed in a layer between the photosensitive and image-receptive layers to effectuate the image difl'usion processing resulting in the positive image.
  • the reflecting agent may be incorporated in a layer initally located between the photosensitive and image-receptive layers prior to exposure of the former or the reflective material which provides a background for the transfer image may be formed in situ during the image-forming processing.
  • Another component of the dye image-forming system incorporated in the film unit structure of the invention is a liquid processing composition adapted, when distributed within the film unit for permeation into the exposed photosensitive layer, to initiate and effectuate the diffusion transfer process resulting in the formation of a dye image in the image-receptive layer viewable by reflective light against a background formed between the image-receptive layer and the photosensitive layer.
  • This processing liquid is usually aqueous, alkaline, and contains a viscosity adding agent such hydroxyethyl cellulose, to aid in the spreading of the liquid in a thin layer within the film unit. It may also contain a reflecting agent such as titanium dioxide.
  • a reflecting agent such as titanium dioxide.
  • the various layers constituting the image-forming diffusion transfer system are supported on and sandwiched between a pair of dimensionally stable and preferably liquid impermeable support layers or sheets.
  • Each sheet and the layers coated thereon during the manufacturing of the film unit may be in the form of separate, individual elements which are laminated to one another by and during distribution of the processing liquid between the elements.
  • the two elements comprising the support sheets and layers coated thereon may be laminated to one another prior to photoexposure to form an integral structure, in which case, the processing liquid is distributed between the layers of the integral structure simultaneously delaminating and laminating these layers to one another to form another integral structure containing an additional layer constituted by the processing liquid.
  • the basic components of the film unit include a first rectangular, sheet-like element designated 10 and a second rectangular, sheet-like element designated 12.
  • Each of these elements comprises a dimensionally stable support sheet coated thereon with some or all of the various layers and strata previously described and/or conventionally incorporated in photographic film units of this type.
  • the first element 10 is preferably opaque to actinic light and includes a support sheet which, during the manufacturing process, is coated at least on one side with the photosensitive layer, generally designated 11 in FIG. 2, including the various photosensitive strata and associated dye image-forming materials.
  • auxiliary layers and strata including the image-receptive layer, a layer for arresting or inhibiting the development process and/or a reflective layer for providing a background for the dye image supported by the image-receptive layer.
  • the layer (or strata) coated on the support sheet comprising second element 12 is generally designated 13 in FIG. 2.
  • the first element is substantially smaller than the second element and, in order to realize the largest possible cost-saving, it should support as many of the various layers as is possible, consistent with the constraints imposed thereon by the manufacturing process, in order that the first element will have a higher cost per unit area than the larger second element. It should be realized, of course, that where additional expense may be incurred by incorporating a particular layer or stratum as a part of the first element will be 'more expensive than coating the same layer or stratum on the second element and such expense will outweigh any possible savings in material, then such a layer or stratum should be incorporated as part of the second element as layer 13.
  • Each of sheet-like elements 10 and 12 comprises a dimensionally stable support sheet and the elements are secured to one another in face-to-face relation with the layers (11 and 13, respectively) coated thereon and comprising components of the dye image transfer system, e.g., the photosensitive and image-receptive layers, sandwiched between the support sheets.
  • the layers 11 and 13 coated on the support sheets of elements 10 and 12 are designed to perform functions involved in the exposure and/or processing of the film unit to form a finished and attractive photographic print.
  • other layers may be coated on the outside of the supports for performing functions such as, for example, altering the optical properties of these supports, preventing abrasion, opacification, and the like.
  • the support for element 10 is preferably opaque to actinic light to permit processing of the film unit in the light (as will be described hereinafter) as Well as to permit a plurality of the film units to be arranged in stacked relation in a film container or cassette and exposure of the film unit at one end of the stack without exposure of underlying film units.
  • the support sheet for second element 12 is preferably transparent to permit photoexposure of the photosensitive layer sandwiched between the support sheets and to permit viewing of the positive transfer image when image formation is completed.
  • materials useful for the support sheets mention may be made of polymeric films derived from ethylene glycol terephthalic acid, vinyl chloride polymers, polyvinyl acetate, cellulose derivatives, and the like.
  • Element 12 is substantially longer and wider than element and includes a leading end section 14 extending beyond the leading edge 16 of first element 10; a trailing end section 18 extending beyond the trailing edge 20 of element 10 and lateral marginal sections 22 extending beyond the lateral edges 24 of element 10.
  • the two sheets are preferably arranged with respect to one another so that the lateral marginal sections 22 are of equal width while the leading end section 14 is substantially longer than trailing end section 18.
  • binding strips 26 are secured together at their lateral edges by a pair of binding strips 26, each secured to the lateral margin of the outer surface of element 10 and to the adjacent lateral marginal section 22 of sheet 12.
  • Materials useful for the binding strips include paper, polymeric films or laminates composed of different ma terials including paper and polymers.
  • the processing liquid for each film unit is supplied in a rupturable container 28 of a type well-known in the art and described, for example, in US. Pat. No. 2,543,181.
  • Container 28 is formed by folding a rectangular blank of a fluid and vapor impervious sheet material medially and sealing the marginal sections of the blank to one another to form a cavity for containing processing liquid designated 30.
  • the seal between the longitudinal marginal sections 32 is weaker than the seals at the ends of the container so that in response to the application of compressive pressure to the walls of the container in the region of the liquid-filled cavity, there will be generated within the liquid hydraulic pressure sulficient to separate longitudinal marginal sections 32 throughout the major portion of their length to form a discharge mouth which is preferably equal in length to the liquid-filled cavity.
  • Container 28 is mounted on leading end section 14 of element 12 with the edge of marginal sections 32 located closely adjacent the leading edge 16 of element 10, and the opposite longitudinal edge of the container at which the blank is folded, is located closely adjacent and in parallel relation with the end edge of element 12.
  • Means are provided for securing container 28 to elements 12 and 14 so as to retain the container in place and provide a passage for conducting the liquid contents of the container from the cavity within the container between layers of elements 10 and 12 as compressive pressure is applied to the container to eject its liquid contents therefrom.
  • These last-mentioned means include an elongated retaining strip 34 folded longitudinally to form two sections, one of which is adhered to element 10 adjacent the leading edge thereof between element 10 and a longitudinal edge portion of container 28.
  • the other section of retaining strip 34 is folded around the longitudinal edge portion of the container and is secured to the outer marginal surface of the container.
  • the overall length of the container is approximately equal to the width of element 10 and retaining means in the form of relatively short retaining strips 36 are secured to the end margins of container 28 and lateral marginal sections 22 of element 12.
  • Retaining strips 36 are preferably equal in length to the width of the container and equal in width to retaining strips 26 so that one end edge of each retaining strip 36 abuts an end edge of one of the retaining strips 26 while the other end edge of each retaining strip 36 is aligned substantially with the leading edge of second element 12.
  • Means in the form of another retaining strip 38 approximately equal in length to the width of element 12, is secured to one marginal section 32 of continer 28 and the outer surface of the leading edge section of element 10 so as to bridge the gap between the container and element 10 and provide a passage for confining the processing liquid within the film unit as the liquid is ejected from the container.
  • Retaining strips 34, 36 and 38 may be formed of the same material as binding strips 26 and are adhered to the elements and the container in the same manner.
  • the liquid contents of container 28 will be spread between the elements as the film unit is moved, container foremost, between a pair of juxtaposed members which first apply compressive pressure to the container to rupture the seal between marginal sections 32, ejecting the liquid from the container between the marginal sections so that it is forced to flow between elements 10 and 12.
  • the bond between a particular pair of adjacent layers or strata will be weaker than the physical bond between any other pair of adjacent layers or strata so that the hydraulic pressure of the liquid which is confined within the film unit, will rupture the laminate where the bond is weakest, permitting the liquid to spread between elements 10 and 12 toward the trailing end of the film unit.
  • FIG. 3 Another function of lateral binding strips 26 is illustrated in FIG. 3 in which there is shown a typical pair of pressure-applying members in the form of rollers 40 and 42 mounted in juxtaposition for rotation about axes located in a common plane.
  • Processing means including rollers are well-known in the art and the rollers are biased toward one another to apply compressive pressure to the film unit, progressing from the leading end toward the trailing end so as first to eject the liquid contents of the container and then distribute the liquid between elements 10 and 12 toward the trailing ends of the elements.
  • Lateral binding strips 26 provide means for predeterminately spacing apart the pressure-applying rollers so as to provide a space between the medial portions of elements 10 and 12 in which the processing liquid can be spread in a layer of predetermined thickness.
  • the greatest cross-sectional thickness of a transverse section of a film unit in the region in which the photosensitive layer is exposed occurs near the margins of the film unit where the lateral binding strips 26 are adhered to the outer surface of element 10.
  • This thickness includes a binding strip, elements 10 and 12, and any additional layers or strata coated on the elements in this region.
  • the aggregate cross-sectional thickness of the portion of the film unit intermediate binding strips 26 will be less so that during spreading of the processing liquid, the medial portions of elements 10 and 12 will be forced apart into engagement with rollers 40 and 42 providing a space between the elements in which the processing liquid is spread. The depth of this space is a function of the thickness of the binding strips.
  • binding strips Other functions performed by the binding strips are to prevent escape of the processing liquid from between the elements 10 and 12 at the margins thereof and prevent admission of air between the elements. Preventing escape of processing liquid at the margins of the film unit is obviously important, not only because such liquid may contaminate the processing apparatus, but the loss of liquid may mean that there will be insuflicient liquid to complete image formation throughout the exposed area of the photosensitive layer.
  • the exclusion of air from between elements 10 and 12 is important because such air tends to interfere with the spreading of the liquid since it must be advanced ahead of the advancing mass of liquid and/or may become entrained in the liquid to form voids in the layer of liquid which appear as defects in the visible image.
  • first and second elements 10 and 12 are secured to one another at their trailing ends by retaining means in the form of a trailing end retaining strip 44, equal in length to the width of element 12 and secured along one edge to trailing end section 18 of second element 12 adjacent the trailing edge of the second element.
  • End retaining strip 44 is folded upon itself and secured along its opposite longitudinal margin to the outer surface of first element adjacent the trailing edge thereof and the trailing end portions of lateral binding strips 26. The ends of retaining strip 44 are adhered to the lateral margins of the trailing end section of element 12.
  • these liquid trapping and retaining means comprise a pocket formed by retaining strip 44 and a spacing element (or elements) 46 enclosed within the pocket by retaining strip 44 and the trailing end section 18 of element 12.
  • Spacing element 46 is designed to space apart the inner surfaces of retaining strip 44 and second element 12 as the pressure-applying members, e.g., rollers 40 and 42, pass over the trailing end of the film unit so that a space remains within the film unit in which the excess processing liquid overrun is trapped and retained.
  • Spacing elements suitable for this purpose are well-known in the art and in the form shown, spacing element 46 consists of a strip formed with openings in which the excess processing liquid can collect.
  • Other forms of spacing elements find equal utility in the film unit of the invention and these include a spacing element of the type shown and described in the copending and commonly assigned US.
  • the film unit includes a masking layer designated 50 designed to perform a number of functions and having as its basic function, the provision of a sharply defined image-free border surrounding a high quality transfer image extending to the edges of the border.
  • Masking layer 50 is applied to the second element during manufacture, extends to the edges of the second element and is formed with a rectangular opening 52 having sharply defined edges. Opening 52 defines the extent of the visible image, is slightly smaller than first element 10 and is symmetrically located with respect to the first element with the edges of opening 52 parallel with and equally spaced from adjacent edges of the second element.
  • edges of the opening 52 are also spaced inwardly from the edges of the film unit so as to be located inwardly from the edges (inner) of binding strips 26 and retaining strips 38 and 44, such that when viewed from the side of the transparent element, the edges of the strips underlie the masking layer.
  • the binding and retaining strips limit and define the region in which the liquid is distributed. This construction in which the edges of the strips underlie the masking layer and are outside the image area is significant because it permits the processing liquid to be distributed laterally and lengthwise beyond the edges of the image area into regions underlying the masking layer.
  • Masking layer 50 may be of any desired color although white is, by custom and usage, the more preferred color; and comprises a pigment such as titanium dioxide carried in a suitable binder, preferably a polymer which is a liquid during formation of the masking layer and solidifies to form a stable adherent layer.
  • the masking layer can be formed or applied to element 12 by a number of wellknown systems including, for example, conventional printing methods such as the gravure process.
  • the masking layer is located layerwise within the film unit such that the processing liquid will be distributed behind the masking layer, that is, to the side thereof opposite the transparent support.
  • the preferred location of the masking layer is betweeen the image-receptive layer 13 and the layers or strata associated therewith as shown in FIG. 2 and may be located directly on the inner surface of support sheet 22. However, depending on the nature and composition of the masking layer and particularly, the composition of the polymeric binder and the density of the reflecting agent, the masking layer may be disposed within the multilayer structure, for example, between the photosensitive layer designated 11 and the image-receptive layer.
  • the polymeric binder of the masking layer is insoluble in the aqueous alkaline processing liquid, is preferably hydrophobic and at most, very slightly permeable to water.
  • the masking layer should be as thin as possible consistent with providing the requisite opacity and reflectance, a function of the density and distribution of the reflecting agent, preferably titanium dioxide.
  • So-called acrylic latex base paints and similar compounds are considered especially suitable for forming a masking layer having the required characteristics mentioned above. An example of such a compound is given as follows:
  • Tamol731 11.0 Antifoamer (e.g., tributyl phosphate) 2.0 Ethylene glycol 22.0 Preservative (sodium pentachlorophenate) 0.5 2% hydroxyethyl cellulose 84.0
  • Antifoamer e.g., tributyl phosphate
  • Ethylene glycol 2.0
  • Preservative sodium pentachlorophenate
  • Tr-ade name of sodium salt of polymeric carboxylic acid sold by Rohm & Haas.
  • masking layer 50 in covering or masking any transfer image formed therebehind is a function of two factors, namely, the permeability of the layer by the dye solvent, e.g., water, and the content or concentration of titanium dioxide.
  • a masking layer having the requisite covering power and reflectance can be formed by coating the above composition on second element 12 to provide a minimum titanium dioxide concentration of the order of 600.0 milligrams per square foot.
  • lower titanium dioxide concentration may provide covering power acceptable for any application depending upon the distribution of titanium dioxide and the location of other layers or strata with respect to the masking layer.
  • higher concentration of titanium dioxide up to a maximum of about 2,500 milligrams per square foot will provide a whiter, higher reflectance border more capable of masking any image formed therebehind.
  • Masking layer 50 is illustrated in FIG. 2 as being coated between image-receptive layer 11 and support sheet 22. This location is preferred for a number of reasons including the fact that the various strata which make up the film unit include an acid-containing or neutralizing layer for reducing the pH to arrest the development process as disclosed, for example, in the copending US. patent application of E. H. Land, Ser. No. 782,056, filed Dec. 9, 1968, now US. 'Pat. 3,573,043.
  • This neutralizing layer generally has associated therewith a spacer or timing layer for delaying the neutralizing reaction and both of these layers are located between the image-receiving layer and the masking layer providing a barrier which aids in preventing permeation of the masking layer by imageforming dyes.
  • a masking layer including a reflecting pigment is formed between the photosensitive and imagereceptive layers throughout the areas thereof in which an image is formed, to provide a reflective background for the transfer image formed in the image-receptive layer and to mask or cover the photosensitive layer and the image formed therewith.
  • This masking and reflecting layer may be formed in a number of ways. For example, as noted in the copending U.S. patent application of Edwin H. Land, Ser. No. 43,782, filed June 5, 1970, an inorganic reflecting pigment such as titanium dioxide is dispersed in the processing liquid which is spread in a layer between the photosensitive layer and the image-receptive layer to provide a layer exhibiting the requisite optical transmission and reflection densities. Obviously, this second masking layer will extend from edge-to-edge of the area in which the processing liquid is distributed so that it will be located behind masking layer 50 where it will contribute further to the masking of any image formed behind masking layer 50..
  • the masking and reflecting layer located betweenthe photosensitive and image-receptive layers to provide a background for viewing the color transfer image may be provided, in whole or in part, as a preformed layer of the film unit such as disclosed in the copending U.S. patent applications of Edwin H. Land, Ser. Nos. 846,441, filed July 31, 1965, now U.S. Pat. 3,615,421 and 3,645, filed Jan. 19, 1970, now US. Pat. 3,620,724; or the reflecting pigment may be generated in situ as is disclosed in the copending US. patent applications of Edwin H. Land, Ser. Nos. 43,741, now US. Pat. 3,647,434 and 43,742, now US. Pat. 3,647,435, both filed June 5, 1970.
  • the masking and reflecting layer will be located behind masking layer 50 so as to further contribute to the effectiveness thereof.
  • Masking layer 50 may be provided between the imagereceptive layer and the photosensitive layer particularly when the binder for the pigment is a polymer that is insoluble in water and forms a layer which is at least poorly permeable and preferably impermeable to the solvent (i.e. Water), of the processing composition or, as disclosed, is essentially hydrophobic.
  • a masking layer 50 provides an effective barrier to the diffusion of the imageforming dyes while the masking and reflecting layer formed between the photosensitive and image-receptive layers and hence between the photosensitive layer and the masking layer 50, will also contribute to the effectiveness of the latter.
  • the masking layer 50 is described as including a polymeric binder which is water insoluble and preferably hypro phobic so that the masking layer is impermeable or at least poorly permeable, the masking layer may also be formed employing a binder which is soluble in water and hence more permeable to the dilfusible image-forming dyes.
  • Suitable polymeric binders of this type useful in masking layer 50 include, for example, gelatin and polyvinyl alcohol.
  • Such layers prove very eflective, particularly when located between the image-receptive layer and support layer 22 although such a masking layer may be located between the image-receptive layer and the photosensitive layer with the masking and reflecting layer which is formed therebetween, further contributing to the elfectiveness of masking layer 50
  • the novel film unit structure in achieving the objects of the invention, represents a substantial advance in the art particularly insofar as it constitutes a construction having fewer and more easily formed and assembled components, and utilizes less material while minimizing waste materials.
  • a more esthetically pleasing product i.e. a photographic print, which is less subject to damage.
  • a photographic film unit adapted to be exposed to form an image and comprising first and second rectangular supports secured in face-to-face relation, a lightsensitive, image-recording layer and an image-receptive layer between said supports, at least said second support being substantially transparent to permit viewing of an image formed between said supports, and a rupturable container of liquid processing composition for forming a visible image in said image-receptive layer when distributed between said supports for permeation into said image-recording layer, the improvement comprising, in combination said second support being larger than said first support and said supports being arranged with margins of said second support extending beyond the edges of said first support;
  • first retaining means secured to the marginal surfaces of said supports facing in the same direction along these edges of said supports to retain the latter in face-to-face relation prior to, during and subsequent to exposure and processing;
  • second retaining means securing said rupturable container to said supports adjacent the fourth edge of said first support for conducting the liquid contents of said container between said supports in response to the application of compressive pressure to said container;
  • a masking layer carried on said second support and located between the latter and said image-recording layer, said masking layer extending to the edges of said second support and having a rectangular medial opening with length and width dimensions smaller than the length and width of said first support and located with the edges of said first support underlying said masking layer.
  • a photographic film unit as defined in claim 2 wherein the inner edges of said end and lateral retaining strips furthest from the outer edges of said second support underlie said masking layer.
  • a photographic film unit as defined in claim 2 wherein said container is rectangular and is mounted on the other end portion of said second support, and said other end portion extending beyond an end edge of said 13 first support has a length at least equal to the shorter dimension of said container.
  • said second retaining means further include a fifth retaining strip secured to the surface of said second support underlying said container, folded around and secured to the outer surface of the margin of said container furthest from said fourth retaining strip.
  • a photographic film unit as defined in claim 2 further including liquid trapping and retaining means secured between said second support and said end retaining strip.
  • a self-developing photographic film unit including a pair of external support sheets, at least one of which is transparent, secured in face-to-face relation, an image-recording layer including at least a light-sensitive silver halide stratum and an associated dye imageproviding material and an image-receiving layer including a dyeable stratum, located between said support sheets, and a rupturable container coupled with said support sheets and containing a liquid processing composition including a solvent for said dye image-providing material, adapted to be distributed between said support sheets for permeation into said image-recording layer to render said dye image-providing material transferable by diffusion to said dyeable stratum, the improvement comprising:
  • a masking layer between said one support sheet and at least said image-recording layer extending to the edges of said one support sheet and having a medial opening smaller than said image-recording layer;
  • said masking layer including a light reflecting agent suspended in a polymeric binder at least poorly soluble in said liquid processing composition for effectively masking from view, portions of said image recording layer and any of said dye image-forming material rendered difiusible to said image-receptive layer and underlying said masking layer.

Landscapes

  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Structural Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
US102447A 1970-12-29 1970-12-29 Photographic film unit Expired - Lifetime US3694206A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US10244770A 1970-12-29 1970-12-29

Publications (1)

Publication Number Publication Date
US3694206A true US3694206A (en) 1972-09-26

Family

ID=22289891

Family Applications (1)

Application Number Title Priority Date Filing Date
US102447A Expired - Lifetime US3694206A (en) 1970-12-29 1970-12-29 Photographic film unit

Country Status (12)

Country Link
US (1) US3694206A (enrdf_load_stackoverflow)
JP (1) JPS5852211B1 (enrdf_load_stackoverflow)
AU (1) AU451552B2 (enrdf_load_stackoverflow)
BE (1) BE777462A (enrdf_load_stackoverflow)
CA (1) CA996389A (enrdf_load_stackoverflow)
CH (1) CH560916A5 (enrdf_load_stackoverflow)
DE (1) DE2163293C3 (enrdf_load_stackoverflow)
FR (1) FR2120952A5 (enrdf_load_stackoverflow)
GB (1) GB1363867A (enrdf_load_stackoverflow)
IT (1) IT945658B (enrdf_load_stackoverflow)
NL (1) NL171746C (enrdf_load_stackoverflow)
SE (1) SE381520B (enrdf_load_stackoverflow)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3804627A (en) * 1972-07-05 1974-04-16 Eastman Kodak Co Film handling improvement
US3944701A (en) * 1972-11-06 1976-03-16 Polaroid Corporation Photographic film unit having gravure coated, tapered thickness layer
US4273852A (en) * 1979-12-26 1981-06-16 Eastman Kodak Company Instant film unit
US4356248A (en) * 1981-05-26 1982-10-26 Polaroid Corporation Photographic product

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4303750A (en) * 1980-06-16 1981-12-01 Polaroid Corporation Alkaline fluid photographic processing composition containers

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

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3804627A (en) * 1972-07-05 1974-04-16 Eastman Kodak Co Film handling improvement
US3944701A (en) * 1972-11-06 1976-03-16 Polaroid Corporation Photographic film unit having gravure coated, tapered thickness layer
US4273852A (en) * 1979-12-26 1981-06-16 Eastman Kodak Company Instant film unit
US4356248A (en) * 1981-05-26 1982-10-26 Polaroid Corporation Photographic product

Also Published As

Publication number Publication date
DE2163293A1 (de) 1972-07-20
CA996389A (en) 1976-09-07
JPS5852211B1 (enrdf_load_stackoverflow) 1983-11-21
AU3699571A (en) 1973-06-21
NL171746C (nl) 1983-05-02
NL7118049A (enrdf_load_stackoverflow) 1972-07-03
DE2163293B2 (de) 1979-11-15
IT945658B (it) 1973-05-10
BE777462A (fr) 1972-06-29
GB1363867A (en) 1974-08-21
CH560916A5 (enrdf_load_stackoverflow) 1975-04-15
FR2120952A5 (enrdf_load_stackoverflow) 1972-08-18
SE381520B (sv) 1975-12-08
AU451552B2 (en) 1974-08-08
NL171746B (nl) 1982-12-01
DE2163293C3 (de) 1980-07-24

Similar Documents

Publication Publication Date Title
US3594165A (en) Novel photographic products and processes
US3652281A (en) Photographic film unit
US3793023A (en) Diffusion transfer film units containing polyethylene glycol, their manufacture and use
US4040830A (en) Photographic products comprising embossed supports
US3652282A (en) Photographic film unit and method of manufacture
US2977226A (en) Photographic process, product and apparatus
US3615540A (en) Photographic film assemblage and method for release of gas in diffusion transfer system
US3706557A (en) Color diffusion transfer film unit containing a temporary barrier for developer restrainers
US3619193A (en) Photographic film unit
US3694206A (en) Photographic film unit
US3607285A (en) Photographic film unit
US3761268A (en) Self developing photographic film assemblage
US3473925A (en) Photographic diffusion transfer color process and film unit for use therein
US3933555A (en) Method of manufacturing photographic film unit
US3619192A (en) Photographic film unit
CA1036857A (en) Photographic products and processes
US3776726A (en) Color diffusion transfer photographic products,processes and compositions
US3679409A (en) Color diffusion transfer processes and elements for use thereon with incorporated image-forming material impermeable layer
US4144065A (en) Polysilicates in photographic products and processes
US3944701A (en) Photographic film unit having gravure coated, tapered thickness layer
US3833381A (en) Photographic products including rupturable containers
US3802881A (en) Color diffusion transfer film with whitening agent
US3816128A (en) Photographic film unit
US3615539A (en) Self-developing photographic film unit and process having secured face-to-face surface
US3741766A (en) Photographic film unit for producing images in color