US3658524A

US3658524A - Photographic film unit comprising silver halide and a dyeable stratum contained on a common support and process employing same

Info

Publication number: US3658524A
Application number: US861768A
Authority: US
Inventors: Joel M Piesach
Original assignee: Polaroid Corp
Current assignee: Polaroid Corp
Priority date: 1969-09-29
Filing date: 1969-09-29
Publication date: 1972-04-25
Anticipated expiration: 1989-04-25

Abstract

Novel systems for preparing dye images utilizing novel film units including a layer of a light-sensitive silver halide, a color-providing material disposed in this layer or in an adjacent layer, which color-providing material is non-diffusible, but, upon oxidation, can release a diffusible color-providing moiety for transfer, said film unit further including a dyeable stratum separable from the aforementioned layer or layers.

Description

United States Patent Piesach 1 Apr. 25, 1972 54] PHOTOGRAPHIC FILM UNIT 3,196,015 7/1965 Ryan ..96/3 COMPRISING SILVER HALIDE AND A oom e a DYEABLE STRATUM CONTAINED ON 3,455,633 7/1969 Land ..96/3

A COMMON SUPPORT AND PROCESS EMPLOYING SAME Primary Examiner-John T. Goolkasian Assistant Examiner-D. J. Fritsch Attorney-Brown and Mikulka and Alvin lsaacs [5 7] ABSTRACT Novel systems for preparing dye images utilizing novel film units including a layer of a light-sensitive silver halide, a colorproviding material disposed in this layer or in an adjacent layer, which color-providing material is non-diffusible, but. upon oxidation, can release a diffusible color-providing moiety for transfer, said film unit further including a dyeable stratum separable from the aforementioned layer or layers.

10 Claims, 3 Drawing Figures SPREADER SHEET PROCESSING COMPOSITION DYE AqX STRIPPING LAYER DYEABLE STRATUM SUPPORT PHOTOGRAPHIC FILM UNIT COMPRISING SILVER HALIDE AND A DYEABLE STRATUM CONTAINED ON A COMMON SUPPORT AND PROCESS EMPLOYING SAME BACKGROUND OF THE INVENTION The copending application of Stanley M. Bloom, Ser. No. 655,338, filed July 24, 1967, describes and claims novel compounds containing a color-providing moiety and an anchoring or immobilizing moiety. These compounds are immobile and non-diffusible in an aqueous alkaline medium, but are capable of providing, upon oxidation, an oxidation product which may auto-react intramolecularly to form a heterocyclic ring and, as a function of this ring formation, to split off a mobile and diffusible color-providing material. This reaction may also be defined as a ring-closure of the oxidation product resulting in a separation or freeing of the mobile color-providing moiety from the anchoring moiety.

US. Pat. No. 3,443,939, issued to Stanley M. Bloom and Robert K. Stephens discloses systems employing the afore mentioned non-diffusible compounds to obtain'negative color transfer images. According to this copending patent application a photosensitive element containing at least one light-sensitive silver halide emulsion and associated compound ,of the foregoing description is exposed and then developed with an aqueous alkaline processing composition including a silver halide developing agent which upon development provides an oxidation product capable of being reduced by a redox reaction with the aforementioned compound, the developer further being sufficiently mobile inv its oxidized state so as to be capable of migrating to the layer containing the colorproviding compound; oxidizing the developing agent as a function of development to provide an imagewise distribution of oxidized developing agent in terms of exposed and developed areas of the emulsion; transferring this imagewise distribution at least in part, to contact the color-providing compound, whereby a redox reaction takes place to reduce the developing agent and to oxidize the color-providing compound to form an oxidation product which then ring-closes to split off the mobile color-providing moiety in turn to form an imagewise distribution of mobile and diffusible color-providing compound in terms of exposed areas of the emulsion; and transferring this latter image-wise distribution, at least in part by imbibition, to a superposed dyeable stratum to impart thereto a negative color transfer image.

SUMMARY OF THE INVENTION The present invention is directed to novel film units and systems utilizing the procedures described in the aforementioned US. Pat. No. 3,443,939.

Specifically, the present invention is predicted upon the discovery that when the dyeable stratum on which the color image is to be formed in accordance with the aforementioned procedures, is contained on the same support as thesilver halide layer, dye images are obtained having appreciably greater density than is obtainable under the same processing conditions in systems wherein the dye must traverse agap to a dyeable stratum contained on a separate element to form the desired dye transfer image.

Accordingly, the present invention is directed to novelfilm units including the aforementioned color-providing material, silver halide and dyeable stratum contained initially on a common support, the dyeable stratum being separable after image formation to provide the desired color image; and photographic procedures employing the same.

BRIEF DESCRIPTION OF DRAWING FIG. 1 is a partially schematic, enlarged, fragmentary sectional view illustrating a photographic product of this invention;

FIG. 2 is a similar view showing a previously exposed photographic product of FIG. 1 during processing thereof; and

FIG. '3 illustrates a color image obtained after such processing.

DESCRIPTION OF PREFERRED EMBODIMENT The preferred embodiment is directed to the formation of color transparencies and the support for the dyeable stratum is accordingly substantially transparent. To facilitate clean separation of the dyeable stratum containing the color image after processing, in the preferred embodiment a stripping layer is disposed between the dyeable stratum and the remaining layer or layers. (See, for example, FIG. I)

As was mentioned previously, this invention relates to photography and, more particularly, to novel products and processes for forming color images.

A primary object of this invention, therefore is to provide novel products and processes of the foregoing description.

Another object is to provide novel procedures utilizing as the color-providing material, a non-diffusible compound containing a diffusible color-providing moiety e.g., a diffusible dye moiety, which compound is capable of forming by a redox reaction with oxidized silver halide developing agent an oxidization product which can auto-react intramolecularly to effect ring-closure and to eliminate the diffusible color-providing moiety of the compound for transfer.

Yet another object is to provide novel photographic products including a support carrying at least one light-sensitive silver halide material having a color-providing material of the foregoing description associated therewith, the support further including a dyeable stratum on which the color image is to be formed.

Still another object is to provide novel products and processes for preparing negative color images, e.g., color transparencies.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordinglycomprises the several steps and the relation and order of one or more of such steps with respect to each of the others and the product possessing the features, properties and the relation of elements which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying draw- :lng.

As was mentioned previously, the present invention utilizes as the color image-forming components compounds containing a color-providing moiety and an anchoring or immobilizing moiety, which are described and claimed in the aforementioned copending application, Ser. No. 655,338. These compounds are immobile and non-diffusible in an aqueous alkaline medium, but are capable of providing, upon oxidation, an oxidation product which may auto-react intramolecularly to form a heterocyclic ring and, as a function of this ring formation, to split off ,a mobile and diffusible color-providing material. This reaction may also be definedas a ring-closure of the oxidation product resulting in a separation or freeing" of the mobile color-providing moiety from the anchoring moiety.

These compounds may be represented by the formula:

wherein:

A and A each represent the atoms necessary to complete a benzene or naphthalene ring, which ring may be further substituted;

D is a color-providing moiety, e.g., a complete dye such as a monoazo, disazo or anthraquinone dye which may, if desired, be metallized in known manner;

Y is any substituent which completes or forms an amide with, and reduces the basic character of the amino group in the 3-position, such as the residue of an acid, linking the colorproviding moiety D to the 3-nitrogen atom, and which is capable of being eliminated during the ring formation to be described with more particularity hereinafter, e.g.,

etc.;

R and R each represent an anchoring or immobilizing substituent rendering the compound nondiffusible, e.g., higher alkyl such as decyl, dodecyl, stearyl, oleyl, etc. linked directly to the aromatic nucleus or linked indirectly thereto through an appropriate linking group, e.g., -CONH-,

etc., an aromatic ring, e.g., of the benzene or naphthalene series, or a heterocyclic ring, which rings may be either bonded to a single carbon atom of the aromatic nucleus or fused thereto, i.e., bonded to a pair of adjacent carbon atoms; or R and/or R may be a plurality of short chain radicals which together provide the anchoring moiety, each of said short chain radicals being linked directly or indirectly to a different carbon atom of the aromatic nucleus formed by the A and/or A moieties;

X is hydrogen, hydroxy, amino, e.g., a primary, secondary or tertiary amino substituent of the formula:

wherein each R may be hydrogen, a hydrocarbon radical, e.g., alkyl, such as methyl, ethyl, butyl, dodecyl, etc., aryl such as phenyl or naphthyl attached through a carbon atom thereof to the nitrogen atom, a cyclic alkyl such as cyclopentyl or cyclohexyl, i.e., where both R 's are alkylene comprising together with the nitrogen atom a heterocyclic ring, a substituted alkyl, such as hydroxyethyl, methoxyethoxyethyl, polyglycoloxyethyl, carboxymethyl, benzyl, phenylethyl, sulfa-phenylethyl, acetylaminophenylethyl, succinylaminophenylethyl, furanemethyl, etc., or a substituted aryl such as methylphenyl, ethylphenyl, etc., or the anchoring substituent X is hydrogen, hydroxy, an amino group such as may be contained by said X moiety, as previously described, or the anchoring substituent R, provided that one of said X and X moieties must be hydroxy or amino;

F is hydrogen, an alkyl such as methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl, cyclohexyl, etc., or a substituted alkyl such as 2-hydroxyethyl, 3-dihydroxypropyl, carboxymethyl, carboxyethyl, carboxybutyl, carboxydecyl, hydroxyethylether, polyglycoloxyethyl, furanemethyl, benzyl, phenylethyl, carboxyphenylethyl, sulfo-phenylethyl, acylaminophenylethyl, etc.; and

n and it each is a positive integer from 1 to 2, provided that when R or R alone or together comprise one of those heretofore named substituents rendering the compound non-diffusible, either or both of n and u may be I but when R and R alone or together do not provide such an anchoring moiety at least one of n and n must be 2.

Preferred are those compounds within the scope of the above formula which are of the following formula:

I OH

wherein the anchoring moiety R or R comprises a long chain amide, e.g., of at least 13 carbon atoms; and nuclear substituted derivatives thereof, e.g., where any of the nuclear carbon atoms not specifically substituted may contain a carboxy, alkyl, alkoxy, amino, chloro, hydroxy or amide substituent.

The present invention utilizes the principles described and claimed in the aforementioned U.S. Pat. No. 3,443,939, to effect transfer of such a color-providing material to a dyeable stratum to impart thereto a negative color image, the essence of the invention being the discovery that where the dyeable stratum is disposed on the film unit containing the silver halide and color-providing material, as distinguished from being contained on a separate element, significantly denser images can be obtained in a given processing time with no significant increase of unwanted color or stain" in the highlight (nonimage) areas. In short, in accordance with the present invention, one may obtain full scale color reproductions wherein the D,,,,,, areas are of appreciably greater density.

The invention will be more readily understood by reference to the accompanying drawing.

As shown in FIG. 1, a film unit 1 of this invention contemplates a support 10 carrying, on one side thereof, a dyeable stratum 12, a stripping layer 14 and a layer 16 containing a light-sensitive silver halide and a color-providing material of the foregoing description, e.g., of formulae A or B, which materials are described and claimed in the aforementioned copending application Ser. No. 655,338.

Support 10 may be transparent or opaque, depending upon whether transparencies or reflection prints are contemplated. It may even be translucent so as to provide a support or base sheet for an image viewable either as a reflection print or as a transparency. In any event, it may comprise any of the support materials heretofore employed for such purposes. By way of illustration, it may be made of cellulose nitrate, cellulose acetate, polyvinyl acetal, polystyrene, polyethylene terephthalate, polyethylene, polypropylene, polycarbonate, etc., paper, glass or other materials. Translucency may be obtained with any of the foregoing transparent materials by application of a layer of a suitable white pigment, e.g., titanium dioxide.

Dyeable stratum 12 may comprise any of the materials heretofore employed in color transfer processes and may for example comprise a polymeric material such as polyvinyl alcohol or a mixture of polyvinyl alcohol and a polyvinyl pyridine, e.g., a poly-4-vinylpyridine. Such strata are described, for example, in U.S. Pat. No. 3,148,061. The dyeable stratum may also include other reagents performing specific desired functions, e.g., hardeners, cross-linking agents or other reagents to reduce water-sensitivity, dye mordants, antifoggants, oxidizing agents, pH adjusters, or the like, all of which additional reagents are known in the art.

Stripping layer 14 is not necessary to the practice of this invention but is preferably employed to facilitate clean separation of the image-containing stratum 12 following processing,

as will be described with greater particularity hereinafter. Stripping layers have heretofore been well known in diffusion processes and per se comprise no part of this invention. As an example of such materials, mention may be made of cellulose acetate hydrogen phthalate.

Layer 16 is shown to contain both the silver halide and the color-providing material. The silver halide may be any of the heretofore employed silver halides, e.g., silver chloride, silver bromide, mixed halides such as silver bromoiodide, silver chlorobromide, or silver chlorobromoiodide. The silver halide is preferably contained in a suitable polymeric matrix, the preferred being gelatino silver halide emulsions such as the known high speed emulsions. The color-providing material may be included in a common matrix with the silver halide or layer 16 may comprise a uniform dispersion of a silver halide emulsion and the color-providing material dissolved or dispersed in a suitable medium. In any event, layer 16 may also include the various other reagents commonly employed in a silver halide layer, e.g., stabilizers, sensitizers and the like and it may also include any of the ingredients needed for development such as the developing agent.

While the color-providing material and silver halide have been shown for purposes of illustration as being in a single layer 16, they may, if desired, be contained in separate layers.

FIG. 2 illustrates one method of developing a previously exposed element of FIG. 1 to form a color image. As shown in FIG. 2, the exposed element is processed by spreading a developing composition 18 in a substantially uniform layer between the exposed element and a superposed spreader sheet 20. To facilitate this uniform spreading, sheet 20 may be made of any sheet material such as those previously mentioned as' useful support, materials. However, sheet 20 is preferably made of a hydrophilic material such as baryta paper which has a greater affinity or adhesiveness toward the processing composition than does stripping layer 14 toward the dyeable stratum. In this manner, following processing, the dyeable stratum is most readily separated from the stripping layer, as will be discussed hereinafter.

Processing composition 18 comprises at least an aqueous medium containing an alkaline material such' as sodium or potassium hydroxide, and a silver halide developing agent of the type described in U.S. Pat. No. 3,443,939, which upon development will provide an oxidation product which can undergo a redox reaction with the color-providing materialin layer 16. Such developing agents include dihydroxybenzene developers such as the hydroquinones, aminophenol developers such as metol, and diaminobenzene developers such as 2-amino5-diethylamino-toluene. Any of these ingredients may be present initially in the photographic assembly, e.g., in layer 16, as noted previously, in which event the developing composition is obtained by applying the aqueous medium to dissolve the component or components so contained. The processing composition may also contain various other reagents performing specific desired functions, e.g., stabilizers, viscous reagents, and the like.

Upon applying the processing compositions such as in the manner shown in FIG. 2, exposed and developable silver halide is developed and as a function of this development an imagewise pattern of oxidized developing agent is, formed in terms of developed silver halide. This imagewise pattern of oxidized developing agent then contacts the color-providing material in layer 16, and this in turn causes the redox reaction referred to above and in U.S. Pat. No. 3,443,939, to occur, thereby releasing the diffusible color-providing moiety to provide an imagewise distribution of the same which is then transferred, by diffusion, to stratum 12 to impart thereto a negative color transfer image. Following. developmentythe dyeable stratum is separated from the stripping layer to reveal the image which, as shown in FIG. 3, comprises layer 12 on support 10, the image being shown as having dye-containing areas 22 and non-image or highlight areas 24. In the preferred embodiment support is transparent and the image shown in FIG. 3 is thus a color transparency.

When spreader sheet 20 is of a hydrophilic material to which the spent processing composition 18 can adhere, upon separation, stripping layer 14 and layer 16 adhere to the spreader sheet, thereby facilitating clean separation of the image-containing portion of the element from the remaining overlying layers.

As was mentioned previously, the present invention makes it possible to obtain denser dye images in a given processing time or a greater delta than is obtainable in analogous systems wherein the released color-providing moiety has to traverse a gap" or space to a dyeable stratum contained on a separate element.

The following examples show by way of illustration and not by way of limitation the practice ofthis invention EXAMPLE I On a mylar (trademark of E. I. duPont de Nemours & Co. for a transparent film of polyethylene terephthalate resin) support sheet was coated a dyeable stratum comprising a mixture of polyvinyl alcohol and poly-4-vinylpyridine at a coverage of about 700 mgm./ft of surface area. Over this was applied a stripping layer by coating a solution of cellulose acetate hydrogen phthalate in acetone to provide a layer containing 60 mgm./ft" of cellulose acetate hydrogen phthalate, 50 cc. of a gelatino high speed silver iodobromide emulsion containing 5.0 g. of gelatin and 6.0 g. of silver was admixed with 10 cc. of an aqueous dispersion containing 1.1 g. of a dye of the formu- .and Lomar D (trademark of Nopco Chemical Division for a sodium salt of a condensed mononaphthalene sulfonic'acid dispersant). The resulting mixture was coated over the stripping layer to provide a layer containing about 30 mgm. of silver and about 70 mgm. of dye per ft of surface area. The above element, illustrative of those of the structure shown in FIG. 1, was exposed to provide a developable image and then processed in the manner shown in FIG. 2 by spreading between the thus exposed element and a superposed baryta spreader sheet a processing composition containing the following proportions of ingredients:

Water 2,000.0 cc.

Hydroxyethyl Cellulose 143.0 g. Sodium hydroxide 78.0 g. Metol 32.0 g. Zinc nitrate 10.0 g. Sodium bromide l00.0 g.

After an imbibition period of about seconds, the dyeable stratum was separated to reveal a negative image having a EXAMPLE 2 A photosensitive element was provided comprising a layer of the above dye and silver halide emulsion on a mylar support. The dyeable stratum was contained on a separate mylar support. Each of the above layers were substantially similar to the corresponding layers. ofthe film unit of Example l,.the

only essential difference being the arrangement of individual layers whereby the dyeable stratum was contained on a separate support, thus providing a separate image-receiving element. The photosensitive element was exposed and then developed by spreading between the respective elements at a gap of 0.0030 inch the processing composition recited in Example 1. After the same imbibition period, the respective elements were separated to reveal a negative transfer image having a D,,,,,, of 1.2.

The foregoing illustrative examples illustrate the increased density obtainable by the present invention under controlled exposure and processing conditions over the image obtainable by transfer to a dyeable stratum contained on a separate element, all other conditions being substantially identical.

While reference has been made to the formation of monochromatic images for purposes of explaining the illustrating the invention, it is contemplated that one may employ two or more silver halide layers with associated color-providing material to obtain multicolor images. Such a film assembly may, for example, include a blue-sensitive silver halide with an associated yellow color-providing material, a green-sensitive silver halide with a magenta color-providing material, and a red-sensitive silver halide with a cyan color-providing material. Such an assembly may, if desired, include one or more spacer layers between the respective silver halide layers.

Since certain changes may be made in the above products and processes without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

l. A photographic product comprising a support carrying on one side thereof a light-sensitive silver halide layer, a layer of a non-diffusible material containing a diffusible colorproviding moiety, which material is capable of forming by a redox reaction an oxidation product which can auto-react intramolecularly to effect ring-closure and to eliminate the color-providing moiety of said material for transfer, and a dyeable stratum disposed between said support and said silver halide and non-diffusible material.

2. A product as defined in claim 1 wherein said layer of nondiffusible material is contained in the same layer as said silver halide.

3. A product as defined in claim 1 including a stripping layer disposed on the surface of said dyeable stratum opposed from said support.

4. A product as defined in claim 1 wherein said support is substantially transparent.

5. A photographic product as defined in claim 1 wherein said non-diffusible material is of the formula:

wherein:

each of A and A represents the atoms necessary to complete an aromatic ring;

D is a color-providing moiety;

Y is a substituent which completes an amide with and reduces the basic character of the 3-amino substituent bonded thereto, said Y substituent further being a divalent radical linking said D moiety to said 3-nitrogen atom;

X and X each is hydrogen, hydroxy, amino or the substituent R, provided that at least one of X and X must be hydroxy or amino;

R and R each represents an anchoring moiety rendering said compound non-diffusible;

R is hydrogen, alkyl or substituted alkyl; and

n and n each is l or 2, provided that when R is an alkyl radical or X or X is a secondary or tertiary amino comprising an anchoring moiety rendering said compound non-diffusible or when R, X and X together contribute an anchoring moiety, n and n may be I, but when said substituents alone or together do not contribute an anchoring moiety at least one ofa n and n must be 2.

6. A photographic product comprising a support carrying on one side thereof, in order, a dyeable stratum, a stripping layer, and a layer containing a light-sensitive silver halide emulsion and a compound of the formula:

wherein:

each of R and R comprises an amide of at least 13 carbon atoms, said amide being bonded directly to a nuclear carbon atom of the shown benzene moiety or linked thereto through a phenylene or alkylenc substituent; each of n and n is l or 2, provided that at least one ofsaid n and n is 2; and D is a monoazo, disazo or anthraquinone dye moiety. 7. A photographic process comprising the steps of exposing a product as defined in claim 1 to form a developable image; developing said image by applying to the thus exposed product an aqueous alkaline processing composition including a silver halide developing agent which when oxidized is capable of undergoing a redox reaction with said non-diffusible material; as a function of said development providing an imagewise distribution of oxidized developing agent in terms of developed areas of said silver halide layer; contacting said non-difi'usible material with said imagewise distribution of oxidized developing agent whereby said material is selectively oxidized by a redox reaction with said oxidized silver halide developing agent to efi'ect said ring-closure and to release said diffusible color-providing moiety in an imagewise pattern corresponding to said imagewise distribution of oxidized developing agent; and transferring said imagewise pattern of diffusible colorproviding material, by diffusion, to said dyeable stratum whereby to impart thereto a color transfer image.

8. A process as defined in claim 7 wherein said color image is a negative transparency.

9. A process as defined in claim 7 wherein said non-diffusible material is a compound of the formula:

wherein:

each of A and A represents the atoms necessary to complete an aromatic ring; D isa color-providing moiety;

Y is a substituent which completes an amide with and reduces the basic character of the 3-amino substituent bonded thereto, said Y substituent further being a divalent radical linking said D moiety to said 3-nitrogen R is hydrogen, alkyl or substituted alkyl; an

n and n each is l or 2, provided that when R is an alkyl radical or X or X is a secondary or tertiary amino comprising an anchoring moiety rendering said compound non-diffusible or when R, X and X together contribute an anchoring moiety, n and n may be l, but when said substituents alone or together do not contribute an anchoring moiety at least 1 or n and n must be 2.

10. A process as defined in claim 9 wherein said development is effected by spreading said aqueous processing composition in a substantially uniform layer between said product and a superposed sheet material.

Claims

2. A product as defined in claim 1 wherein said layer of non-diffusible material is contained in the same layer as said silver halide.
3. A product as defined in claim 1 including a stripping layer disposed on the surface of said dyeable stratum opposed from said support.
4. A product as defined in claim 1 wherein said support is substantially transparent.
5. A photographic product as defined in claim 1 wherein said non-diffusible material is of the formula:
6. A photographic product comprising a support carrying on one side thereof, in order, a dyeable stratum, a stripping layer, and a layer containing a light-sensitive silver halide emulsion and a compound of the formula:
7. A photographic process comprising the steps of exposing a product as defined in claim 1 to form a developable image; developing said image by applying to the thus exposed product an aqueous alkaline processing composition including a silver halide developing agent which when oxidized is capable of undergoing a redox reaction with said non-diffusible material; as a function of said development providing an imagewise distribution of oxidized developing agent in terms of developed areas of said silver halide layer; contacting said non-diffusible material with said imagewise distribution of oxidized developing agent whereby said material is selectively oxidized by a redox reaction with said oxidized silver halide developing agent to effect said ring-closure and to release said diffusible color-providing moiety in an imagewise pattern corresponding to said imagewise distribution of oxidized developing agent; and transferring said imagewise pattern of diffusible color-providing material, by diffusion, to said dyeable stratum whereby to impart thereto a color transfer image.
8. A process as defined in claim 7 wherein said color image is a negative transparency.
9. A process as defined in claim 7 wherein said non-diffusible material is a compound of the foRmula:
10. A process as defined in claim 9 wherein said development is effected by spreading said aqueous processing composition in a substantially uniform layer between said product and a superposed sheet material.