JPS5840175B2 - kakusantenshashinseihin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to photography and more particularly to the formation of color images by diffusion transfer processes.

A number of diffusion photographic transfer methods have been proposed in which the resulting photograph comprises a developed silver halide emulsion held together with a dye image bearing layer as part of a permanent laminate.

This image bearing layer is separated from the developed silver halide emulsion in the stack by a light reflecting layer, preferably a layer containing titanium dioxide.

An example of a patent describing this product and method is Howard G. Rogers.
U.S. Patent No. 298360, granted on March 9, 1961
6. Nidwin H,L
U.S. Patent A3415644. 3415645 and 3415646, Howard G.
US Patent A granted to Rogers on July 2, 1971
3594164 and 3594165 and U.S. Patent A issued to Nidwin H.Rand on March 7, 1972.
, 3647347.

With further particular reference to the aforementioned U.S. Pat. Photographic products and methods are remembered that utilize dye developers to provide laminates comprising a silver halide emulsion and an image-receiving layer.

Exposure is through a transparent (support) element and application of a processing composition provides a layer of light reflective material to provide a white background for viewing the image and to mask the developed silver halide emulsion.

The desired color transfer image is viewed through the transparent support against the white background.

Although this method is very useful and provides images of good quality, it has been found that the images have a tendency to discolor over time.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel diffusion paper transfer photographic film unit and method which provides a high quality dye image as part of a permanent laminate and which dye image exhibits good resistance to discoloration over time. It is in.

Another object of the present invention is to provide a diffusion transfer color process in which silver halide that is not developed during dye image formation is reduced to a non-image form.

Yet another object of the present invention is to provide a further improved method of color diffusion transfer in which silver halide solvents are used to improve the sensitometric properties of integral negative-positive reflection prints. be.

Other objects of the invention will become clear from the description below.

Accordingly, the present invention is a product having the characteristic ingredients and properties of the ingredients, which are exemplified in the following detailed description and whose scope of application is indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description of the invention in conjunction with the accompanying drawings.

As mentioned above, the present invention provides that the layer containing the diffusion transferred dye image, i.e. the image-receiving layer, is not separated from the developed photosensitive layer after processing, but that the surrounding components are retained together as part of the permanent laminate. Pertains to diffusion transfer method.

A film unit particularly suitable for providing this diffusion transfer image is often referred to as an 11 integral negative-positive 1+ film unit.

The resulting image is referred to as a ``integral negative-positive reflection print 1'', and is so called because the developed photosensitive layer is separated from the image-receiving layer, the layer containing the transferred dye image. It is not intended to indicate a reflective print.

A light reflective layer between the developed photosensitive layer(s) and the image layer provides a background for the dye image and masks the developed photosensitive layer(s).

These layers are part of a permanent laminate that usually includes a dimensionally stable outer layer or support layer, one of which the transferred dye image can be viewed.

The present invention is concerned with preventing or at least minimizing discoloration (darkening) of the "white" or highlights of this integral negative-positive reflective print.

The present invention is applicable to a wide variety of color diffusion transfer methods, and the arrangement and order of the individual layers of film used in this color method may be modified if the final image is an integral negative-positive reflection print as described above. can be varied in many ways as known to those skilled in the art.

However, for convenience, the more specific description of the invention uses a negative-positive film unit integrated with a dye developer diffusion transfer color process of the type described in the aforementioned US Pat. No. 3,415,644.

The presence of small amounts of silver halide solvent during development is known to have a desirable effect on sensitometric results.

The addition of this silver halide solvent has been found to be useful in color diffusion transfer processes even though silver paper mapping is not desired or formed.

It has been found that the combination of sodium thiosulfate and potassium thiosulfate in dye developer color transfer processes results in increased photographic sensitivity or "speed 11."

In this integral negative-positive reflection print, the various layers, including the laminate, are processed for a period of time much longer than the processing time, i.e., the time required to simply develop the exposed silver halide and form a transferred image. 11° humidity.

This prolonged wetness condition causes reactions to occur which adversely affect the color transfer image.

These other reactions are most easily evidenced by changes in the highlights or white color of the color image.

The incorporation of a pH reducing mechanism into the film unit, such as the acidic polymer layer described in the aforementioned U.S. Pat. Although it has been found that these problems can be greatly reduced by not using silver halide solvents, problems still exist after a period of time when silver halide solvents are used.

This darkening is due, at least in part, to the fact that a certain amount of complexed silver is actually non-imaging, even though said image-receiving layer does not contain any silver precipitating agent, i.e. no silver precipitating agent is included therein. It has now been found that this is due to the transfer to the image-receiving layer in a similar manner.

Although the transferred silver complex is colorless or white, subsequent photolysis or optical reduction has the effect of reducing the complexed silver to a colored species that is metallic silver.

If the photographic laminate is previously exposed to a significant amount of light, the water within the laminate is removed by evaporation or transpiration through the support, and sufficient complexed silver is photolytically reduced to 0, 3 or This gives an increase in the reflection density of the ``white'' area by more than that.

The undesired transfer of unreduced silver complexes to the image-receiving element can be prevented by adding halogenated compounds such as sodium thiosulfate, which are believed to improve sensitometry and reduce the long duration of the 11 wet 1' condition of the laminate. This is thought to be caused by the inclusion of a silver solvent into the system.

By ensuring that the various silver halide-containing agents used in the present invention are utilized substantially completely during or immediately after transfer image formation, before the silver complex is transferred to the image-receiving layer, the color It has now been found that the transferred image is improved and darkening is substantially reduced or essentially eliminated.

That is, particularly when the layer of silver precipitation nuclei is provided between the silver halide emulsion and the light-reflecting layer and adjacent to the light-reflecting layer, the light-sensitive layer and the image-receiving layer are It has now been found that color transfer images with good highlights and sensitometry can be obtained using film units held as a laminate.

In accordance with the present invention, the transfer of silver to the layer of silver precipitation nuclei and its reduction to metallic silver is delayed until after the desired image dye density is obtained.

Silver precipitation on the rear side of the light-reflective layer cannot be reliably seen by an observer of the color transfer image (because the silver precipitation is hidden by the reflective layer).

This transfer and reduction of silver halide to silver not only ensures that any silver halide dissolved by the processing composition is precipitated in a location that is not detrimental to the quality of the transferred image, but is also desirable in the transferred dye image. provides a mechanism to ensure that unused image dye is excluded from the transfer.

Furthermore, more complete development of the silver halide present requires additional consumption of alkali, thereby providing another pH adjustment mechanism.

The silver deposited in the silver precipitate layer is non-image-like.

As mentioned above, it has been taught by those skilled in the art that in dye developer transfer processes, the addition of silver halide solvents, such as sodium thiosulfate, is useful to increase effective film speed.

Examination of the image-receiving element when it is separated from the photosensitive element after transfer imaging is complete, for example about 60 seconds, shows that very little, if any, silver ions are present. Ta.

It was therefore surprising to discover that undesirable complexed silver can and has been transferred to the image-receiving layer in which the transferred image layer is part of a permanent laminate containing developed silver halide emulsions. Met.

Furthermore, the transfer of image dye from the fully developed areas of the light-sensitive silver halide emulsion to the stacked areas of the image-receiving layer is substantially effected such that the areas of the transferred image are essentially dye-free and white. 1 per square foot from a fully exposed and fully developed silver halide area that should be completely blocked.
It was surprising to discover that certain amounts of complexed silver, on the order of 0 to 40 m9, can cause undesirable transfer to the image-receiving layer.

The art has taught the use of sulfur-containing silver halide solvents, such as sodium or potassium thiosulfate, sodium or potassium thiocyanate.

However, current testing indicates that this silver halide solvent forms soluble silver complexes that can be photolytically reduced to undesired silver.

Although the exact mechanism is unknown, the thio-containing silver halide solvent decomposes and provides nucleation sites for the complexed silver, thereby leading to the undesirable reduction of the complexed silver and the formation of colored species-containing silver. It is thought that this will make it easier.

The inclusion of acid-reactive agents that lower the pH by neutralizing the alkaline system actually reduces this halogenation to photolytic reduction.
Increases the susceptibility of solvents and their silver complexes to photolytic reduction.

Although the provision of UV absorbers is useful in reducing the severity of this photolytic darkening, the most effective UV absorbers also absorb visible light and reduce the tint or themselves until they reduce the whiteness of the emitted image. It has a tendency to introduce colors.

Silver halide solvents are problematic, however, as disclosed in U.S. Pat.
As described and claimed in JP-A-48-74223, the use of silver halide solvents that do not contain sulfur atoms significantly reduces darkening upon exposure to light.

Particularly useful silver halide solvents are cyclic imides, such as uracil.

For example, substitution of 5-methyluracil for potassium thiosulfate was found to reduce Dmin density increase by about 75%.

A second sulfur-free silver halide complexing agent capable of forming relatively sparingly soluble silver complexes, e.g. 6-alkylaminopurine such as 6-benzylamino-purine, is
Substantially all photolytic darkening can be prevented if substituted for a sulfur-containing secondary silver halide complexing agent such as phenyl-5-mercaptotetrazole.

Even though analytical investigations confirm that similar amounts of silver ions are still transferred to the dye image-containing layer, thus confirming the presence of silver ions in a form highly resistant to photodegradation, the “white” This holding of one area is performed.

Particularly useful silver halide solvents that do not contain sulfur atoms are cyclic imides, such as Nidwin Etch Rand, etc.
US Patent A2857274, granted 58.10.21
and especially uracils such as uracil, 5-methyluracil and 6-methyluracil.

The invention further has the advantage of minimizing undesirable photolytically reducible silver complexes in the dye image layer when using silver halide solvents (which may or may not contain sulfur atoms). The present invention relates to a diffusion transfer color method for forming integral negative-positive reflective prints.

Suitable silver halide solvents are alkali metals, other thiosulfates or thiocyanates, as well as the cyclic imide silver halide solvents mentioned above and other known silver halide solvents.

This silver halide solvent is a relatively inert silver salt or complex,
For example, it can be used in combination with a second silver halide complexing agent capable of forming 1-phenyl-5-mercaptotetrazole and other mercaptans described in the prior art as being useful as development inhibitors.

For example, Howard Gee Rogers and Harriet W.

] [, utes), U.S. Pat.

A suitable group of sulfur-containing compounds of this type is
698 and US Pat. No. 3,785,813.

Tetrahydro-pyrimidine-2-thione and hexahydro-4.5-trimethylene-pyrimidine-2-thione are particularly useful.

A very useful sulfur-free compound that can form relatively sparingly soluble complexes with silver is of the formula 6-alkylamino-purine.

Here, the alkyl group is a simple alkyl group, and generally good results are obtained when the alkyl group contains one or two carbon atoms.

As is clear from the above, this alkyl group is a halogen,
The use of this 6-alkylamino-purine in dye developer processing is described in U.S. Pat.
No. (Japanese Unexamined Patent Publication No. 48-74224).

It has further been found that the sensitometric properties of the dye transfer image can be controlled by varying the respective concentrations of the silver halide solvent and the second silver halide complexing agent which provides a relatively insoluble silver complex.

1 and 2 show, in a simplified or implied form, the arrangement of layers in a photographic film of the type to which the invention relates, with the film or film unit being depicted as an integral laminate after processing and imaging.

Since the two film units shown have many elements in common, the two figures will be discussed together.

As can be seen, the diffusion transferred image in the image-receiving or image-bearing layer 12 is transferred to the transparent support 2 to the light-reflecting layer 14.
0, which then masks the developed silver halide emulsion S.

In FIG. 1, an opaque support 18 completes the film unit 10.

This light-reflecting layer 14 preferably contains a white pigment, especially titanium dioxide.

...only one layer 16 of silver halide emulsion is shown,
In the multicolor embodiment, the silver halide emulsion 0 layer 1116 contains a number of silver halide emulsions (blue, green and red light sensitivity).

The image-providing material associated with each of the silver halide emulsions, either in the same layer or in adjacent layers, has a complementary color to the light to which the silver halide emulsion with which it is combined is exposed, as is known in subtractive color techniques. Provides a colored image dye or an intermediate for an image dye.

In accordance with the present invention, a layer of silver precipitant 26 is disposed between developed silver halide emulsion 16 and image-receiving layer 12.

Soluble silver complexes formed in either exposed or unexposed areas of silver halide emulsion 16 cannot diffuse into image-receiving layer 12;
This is because the silver precipitate layer 26 is masked by the light reflective layer 14 .

Silver precipitating agents useful in the present invention can be readily selected from among the many materials taught to those skilled in the art to be useful in silver paper copying.

Examples of particularly suitable silver precipitating agents are metallic sulfides and selenides and the colloidal metals described in US Pat. No. 2,698,237.

As will be readily apparent, appropriate care should be taken to ensure that the silver precipitant is confined within its own layer and is not introduced into other layers where it may adversely affect sensitomere.

During the exposure of a photograph, e.g.
It will be appreciated that while exposure is performed through the transparent support 20 as shown at 644, the film elements are stacked and include an integral film unit.

Alternatively, the image-receiving layer 12 and its transparent support 20 can be separated from the photosensitive layer during exposure, and the resulting laminate has a light reflecting layer distributed therebetween, as described, for example, in the aforementioned U.S. Pat. No. 2,983,606. A treatment composition containing a color pigment is formed by stacking each element.

If the film unit is to be processed outside the darkroom, i.e. removed from the camera before image completion, and if the film is still light-sensitive, suitable opacifying agents and/or layers should be provided.

Particularly useful opacifying systems for film units providing integral prints of the type shown in FIG. 1 and the above-mentioned U.S. Pat. A pH-sensitive optical filter agent or dye is used, as detailed in patent US Pat. No. 3,647,437.

In a film unit suitable for providing a laminate of the type shown in FIG. Served on top.

This is done by distributing a processing composition that provides an opaque layer 22, for example a layer comprising carbon black, between the photosensitive layer 16 and the transparent support 24.

The separately opaque layer 22 is omitted and photoprotection is provided by an opaque layer (not shown) deposited either on the transparent support 24 or directly on the photosensitive layer 16 after exposure.

In a preferred film construction for obtaining an integral negative-positive reflection print of the type shown in FIG. 1, exposure is carried out through the same transparent support on which the final dye transfer image is viewed.

In a preferred film construction for obtaining an integral negative-positive reflective print of the type shown in FIG. 2, the exposure is through a transparent support and an opaque layer 22 protects the exposed silver halide from further exposure. is obtained by including a light-absorbing opacifying agent, such as carbon black, in the processing composition distributed between the photosensitive layer 16 and the transparent support 24.

In this film unit, between the preformed light reflective layer 14 and the silver halide emulsions 16 is a preformed opaque layer (not shown), such as a polymer permeable to a processing composition. It is desirable to include a dispersion of carbon black therein.

Examples of this are the aforementioned U.S. Pat.
No. 594,165.

If desired, the silver precipitant, instead of being in a separate layer, may be placed in a preformed opaque layer into which the processing composition can penetrate.

Generally, the image-providing materials that can be used in this method are (1) initially soluble or diffusible in the processing composition, but become selectively non-diffusive into the imaged pattern depending on the extent of development; or (2) either initially insoluble or non-diffusible in the processing composition, but becoming selectively diffusive in an imagewise pattern or providing a diffusible product upon the action of development; It is characterized by

These image-providing materials may be complete dyes or dye intermediates, such as color formers.

The necessary differences in mobility or solubility are obtained by chemical reactions, such as redox reactions or coupling reactions.

Examples of soluble or diffusible image-providing substances and their applications in color diffusion transfer are first described, e.g. in US Pat.
774668 ; 2968554 ; 2983606
;2087817;3185567;32300
82; 3345163; and 3443943.

The first example of a non-diffusible image-providing material and its use in color transfer systems is U.S. Pat. No. 3,185,567:
3443939; 3443940; 32275
50 and 3227552.

Both types of image-providing materials and film units useful therewith are also disclosed in the aforementioned U.S. Pat. No. 3,647,437.
It is described in.

In both of these systems, polychromatic images are produced by the use of a film unit containing at least two selectively sensitized silver halide layers, each in combination with an image-providing material exhibiting the desired spectral absorption characteristics. can get.

The most commonly used elements of this type are Nidwin
196 to Haughty Land and Howard Gee Rogers
7.10.3 Granted U.S. Patent A, 3345163
The so-called tripack structure uses blue-one green- and red-sensitive silver halide layers in combination with yellow, magenta and cyan image-providing materials, respectively, as described in .

A particularly useful system for forming color images by diffusion transfer uses a dye developer (also...a dye that is a silver halide developer) as the donor material, US Patent A, 298360.
6.

In this system, a photosensitive element comprising at least one silver halide layer having in combination (in the same or adjacent layer) a dye developer is developed by applying an aqueous alkaline processing composition. .

The exposed and developable silver halide is developed by a dye developer, which is then oxidized to yield an oxidation product that is considerably less diffusive than the unreacted dye developer, thereby... providing an image distribution of unoxidized diffusible dye as unexposed areas of the layer, which image distribution is then at least partially transferred to the dyeable layer by diffusion to give a positive dye transfer image thereto; give.

Multicolor images are obtained in photosensitive elements having a dye developer in combination with two or more selectively sensitized silver halide layers and are described in US Pat.
Tripack structures of the type described in various patents, including No. 345,163, are particularly suitable for accurate color recording of original objects.

The color diffusion transfer system includes (a) at least a light-sensitive layer, e.g. a gelatin silver halide emulsion layer having an image-providing material combined in the same or adjacent layers;
(b) developing the exposed element with a processing composition to form an image of the diffusible image-providing material; This image shape is transferred (at least in part, by diffusion) to a layer called a papposi portion, which has a superimposed image-receiving layer, i.e. a dyeable layer providing a color transfer image. A color transfer image is obtained by transferring the distribution.

The photographic film unit of the present invention comprises: (a) the negative and positive components are initially held on two separate supports that are held together during processing and then held together as a final partial negative-positive reflection print; or (b) they are a single structure, e.g. the negative and positive components are part of a photosensitive laminate or they are assembled together in a stacked relationship before, during and after imaging. It may be an integral negative-positive film unit (a) or (b) physically held together on two supports.

(The process for forming a film unit in which the positive and negative portions are temporarily laminated together before exposure is described by, for example, Albert J.B.
achelder) and Frederick J. Binda, U.S. Patent J'/6.3652281, and Nidwin H.
No. 972°3.28 patent).

) In either case the positive component is not removed from the negative component for viewing purposes.

A preferred film unit includes a number of requisite layers including at least one photosensitive silver halide and a negative component comprising an associated image-providing material and a positive component comprising a dyeable layer.

These components may be laminated together or otherwise affixed together in physical proximity as an essentially unitary structure.

A film unit intended to provide a polychromatic image consists of two or more suitable image-providing substances, each in combination with a suitable image-providing substance which imparts image dye spectral absorption properties of substantially complementary colors to the light to which the combined silver halogenide is exposed. Contains a further selectively sensitized silver halide layer.

The most commonly used negative elements for forming polychromatic images are tripac structures and blue-, green-, and red-sensitive elements having a combination of yellow, magenta, and cyan image-providing materials, respectively, in the same or adjacent layers. Contains a silver halide layer.

If desired, interlayers or spacer layers may be provided between each silver halogenide layer and the associated image-providing material or between other layers.

Besides the above-mentioned essential layers, this film unit further comprises:
A dyeable layer and a negative to effectively mask the silver image or images formed as a function of development of the silver halide layer or layers and also to mask the image-providing material that is not transferred. Means is included for providing a reflective layer between the components, thereby providing a background, preferably white, for viewing the colored image formed in the dyeable layer by reflected light without separation.

The reflective layer may include a preformed layer of reflective agent contained within the film unit, or the reflective agent may be provided after exposure, eg, by including the reflective agent in the processing composition.

This dye transfer image can then be viewed through a dimensionally stable protective layer or support.

Suitably other dimensionally stable layers or supports, transparent or opaque, are opposites of the essential layers such that said essential layers are between a pair of dimensionally stable layers or support members. One of these is transparent so that the color transfer image can be seen through them.

Destructible containers of public record are mandatory.

Destructible containers of known record contain the necessary processing composition and facilitate the development of exposed film units, for example, by dispensing the processing composition in an essentially uniform layer between a pair of predetermined layers. suitable for releasing its contents upon application of pressure.

In a film unit providing an integral negative-positive reflective print of the type shown in FIG. 1, a processing composition containing a white pigment is distributed between the dyeable layer and the negative component to provide the light reflective layer 14. .

Suitable opacifying systems to be included in the processing composition for off-camera processing are disclosed in the aforementioned U.S. Patent A, 3647.
437, and includes a dispersion of an inorganic light-reflecting pigment, which also provides a light-sensitive silver halide with respect to the active incident radiation when the processing composition is applied.
．． Pk of the optical filter agent at a concentration effective to provide a layer exhibiting an optical transmission density of >0 concentration units and an optical reflection density of >10 concentration units with respect to incident visible radiation.
and at least one light absorbing agent, ie, an optical filtering agent.

Instead of having a light-reflecting pigment in the processing composition, the light-reflecting pigment used to mask the photosensitive layer and provide the necessary background for viewing the color transfer image formed in the receiving layer is It may be present in whole or in part initially as a preformed layer in the unit.

As an example of this preformed layer, 1971.10.26, both in the name of Nidwin Etch Land
Granted US Patent A 3615421 and 1971.1
1.16 US Pat. No. 116.3620724.

The reflector is Nidwin Etch Land's 1972.3.
7 patented US patents 3647434 and 364743
generated on the fly as described in 5.

The image-providing material may be selected for its ability to provide colors useful in practicing subtractive color photography, namely cyan, magenta, and yellow as noted above.

These are incorporated into each silver halide emulsion or, in preferred embodiments, in a separate layer after each silver halide emulsion.

Thus, the image-providing material is, for example, in a subsequent coating or layer of each silver halide emulsion, and this layer of image-providing material is a film-forming natural, film-forming material suitable for being penetrated by the processing composition. or applied to a synthetic, polymeric, e.g. gelatin, polyvinyl alcohol by use of a coating solution containing each image-providing substance distributed in a concentration calculated to give the desired breakdown of image-providing substance per unit. be done.

Dye developers of image-providing materials are compounds that contain a chromophoric system of dyes and also a silver halide developing function.

. Means a grouping suitable for developing silver halide exposed by a silver halide development function +1.

A preferred silver halide development functionality is a hydroquinonyl group.

Other suitable development functions are ortho-dihydroxyphenyl and ortho- and para-amino substituted hydroxyphenyl groups.

Generally, the development functionality comprises a pensosoid development functionality, ie, an aromatic development group that when oxidized produces a quinoid or quinone material.

The image-receiving layer may include one of the materials known to those skilled in the art, such as polyvinyl alcohol, gelatin, and the like.

It may contain agents suitable for mordants or otherwise fix the transferred image dye(s).

Suitable materials include Howard C.
Polyvinyl alcohol or gelatin with a dye mordant such as poly-4-vinylpyridine as described in US Pat.

If the color of the transferred image dye(s) is affected by a change in pH, the pH of the image layer is adjusted to give the desired color.
adjusted to provide H.

In the various color diffusion transfer systems previously described and using aqueous alkaline processing fluids, acid-reactive agents are used in the layers of the film unit to increase image stability substantially subsequent to dye transfer, and the pH of the environment is adjusted accordingly. It is well known to lower the pH and/or adjust the pH from a first pH at which the image dye is diffusive to a second (low L.) pH at which it is not.

For example, the above-mentioned US Pat.
A system is described in which H reduction is accomplished by providing a polymeric acid layer adjacent to the dyeable layer.

These polymeric acids are polymers containing acid groups, such as carboxylic acid and sulfonic acid groups, which can form salts with alkali metals or organic bases: or potentially with anhydrides or lactones. It is an acid-forming group.

Preferably, the acid type combination may contain free carboxyl groups.

Separately, acid-reactive agents are disclosed in U.S. Pat.
3, it may be present in the layer adjacent to the silver halide furthest from the image-receiving layer.

Another system for providing acid-reactive agents is U.S. Pat.
, 3576625.

An inert interlayer or spacer layer is present between the polymeric acid layer and the dyeable layer to control or "time" the pH reduction so as not to prematurely and interfere with the development process. , and preferably located.

Spacer or II timing 1 suitable for this purpose
One layer is in particular US Patent A3362819;
;3421893 ;3455686; and 3575
701.

The dyeable layer and the photosensitive layer may be contained in separate layers, e.g. between the support for the receiving element and the dyeable layer, or the dyeable layer and the photosensitive layer in an integral film unit, e.g. a negative component. It is preferred to contain an acid layer (contained in the positive component used in the system and a spacer layer in combination therewith) which are bonded on the side of the dyeable layer opposite from It may be combined with a photosensitive layer as described in US Pat. No. 3,362,821 and 3,573,043.

In film units such as those described in the aforementioned US Pat.

As is well known and illustrated, the liquid processing compositions cited for carrying out the multicolor diffusion transfer method, for example in the Penalty Cited Patent, include aqueous solutions of alkaline materials, such as sodium hydroxide, potassium hydroxide, etc. and preferably has a pH of 12 or higher, and most preferably forms a relatively hard and relatively stable film when the composition is spread and dried. Contains viscosity-increasing compounds.

Suitable film-forming materials mentioned include high molecular weight polymers, such as polymeric, water-soluble ethers that are inert to alkaline solutions, such as evaporative hydroxyether cellulose or sodium carboxymethyl cellulose.

Additionally, it has been found that film-forming materials or thickeners are available whose ability to increase viscosity is largely unaffected when left in solution for extended periods of time.

As mentioned above, the film-forming material preferably has about 2
100 cps or more at a temperature of 4°C, and preferably from 100,000 cps to 200,000 cps at this temperature
It is included in the treatment composition in a suitable amount to impart a viscosity to the composition on the order of s.

The invention will be further illustrated by the following working example, which is for illustrative purposes only.

Examples Cyan: A multicolor photosensitive element is prepared using a magenta and yellow dye developer by coating a gelatin precoated 4 mil opaque polyethylene terephthalate film base with the following layers: did.

1, about 100 rngs/f t2 dye and about 80mg
a layer of cyan dye developer dispersed and coated in gelatin with a gelatin coverage of 5/ft"; 2, about 140
Red light-sensitive gelatin silver iodine bromide emulsion coated with a coverage of about 70 mg s/f t2 of silver and about 70 mg s/f t2 of gelatin; 3, about 5 m with a copolymer of about 150 mg s/f t2
A layer of polyacrylamide with a 60-30-4-6 copolymer of butyl acrylate, diacetonamide, styrene and methacrylic acid coated with a coverage of polyacrylamide of g s/f t2; 4, about 112 mgs/f
A layer of magienta dye developer dispersed and coated in gelatin with a coverage of about 100 mgs/ft2 of gelatin with t2 dye: 5, about 100 mgs/ft2 of silver and about 50 mg
Green light-sensitive gelatin silver iodine bromide emulsion coated with gelatin coverage of s/f t2; 6, about 100 mgs/f t2 copolymer and about 12 m
A layer containing polyacrylamide and the copolymer listed in point 3 above coated with a coverage of polyacrylamide of about 70 mg5/ft2 of dye and about 56 mgs/f
A layer of yellow dye developer dispersed in gelatin and coated with t2 gelatin coverage; 8 about 120 mgs/f t2 silver, about 60 mgs
/f t2 of gelatin and auxiliary developer coated with a coverage of approximately 30 mgs/f t2 of auxiliary developer 4'-
a blue-sensitive gelatin silver iodine bromide emulsion layer containing methylphenylhydroquinone; and 9. a layer of gelatin coated with a gelatin coverage of about 50 mgs/ft t2.

A very thin coating of zinc sulfide in colloidal silica is applied to the surface of the photosensitive element to provide a silver precipitable layer.

A clear 4 mil polyethylene terephthalate film base is subsequently coated with the following layers to form the image-receiving acid content: 1. Approximately 2500 mgs/ft t2 as a polymeric acid layer.
Partial butyl ester of polyethylene/maleic anhydride copolymer with an application range of 2 about 500 mg s/f t2 about 40
:1 ratio of a 6030-4-6 copolymer of butyl acrylate, diacetone acrylamide, styrene and methacrylic acid, and polyacrylamide; 2 of alcohol and poly-4-vinylpyridine
A polymeric image-receiving layer containing a :1 mixture.

The two components thus prepared are secured at each edge in a stacked form with pressure-sensitive tape to have a breakable container containing an aqueous alkaline treatment solution secured at the leading edge of each of the components. , provides an integral film unit so that upon application of compressive pressure to the container to break the seal at the edge of the container, the contents are approximately separated between the image-receiving layer and the gelatin overcoat layer of the photosensitive component. Distributed in layers 0.0026" thick.

The aqueous alkaline treatment composition contained: potassium hydroxide (85%) titanium dioxide hydroxyethylcellulose (Vercules type 250M
(medium viscosity) benzotriazole zinc nitrate 6-methyl-5-bromo-4-azobenzimidazole N-benzyl-α-picolium bromide (50% aqueous solution) N-phenethyl-α-picolium bromide 6-
Methyluracil bis=(β-aminoethyl)-sulfidehexahydro-4,6-trimethyl-pyrimidine-2-thione 7.2
41 21.1 f 2.78S' 1.17 1 0.29PP O159g1.17 g0.29 g1.21 1 0.084P 0.22P The photosensitive element is passed through the transparent support and the layer above it. Once exposed, the treatment composition was distributed to the exposed area through the film unit between a pair of pressure supply rolls.

Due to the distribution of the processing composition, the resulting laminate remains intact to produce an integral negative exhibiting good color quality and color separation.
Provides a positive reflective print.

Accelerated aging tests of reflective prints obtained from laminates having a silver precipitate layer as described above show that the darkening of the highlights due to silver ions transferred to the image-receiving layer is at least 5.
It showed that it was reduced to 0%.

When a similarly prepared monolithic negative-positive reflective print is peeled off and examined approximately 5 to 10 minutes after application of the treatment composition, a black silver, substantially non-image-like layer is visible. It was found that the silver was present as an entrapped layer in a silver precipitant layer between the blue sensitized silver halide emulsions of the reflective titanium dioxide layer.

It will be appreciated that the concentrations of silver halide solvent and other silver halide complexing agents may be varied over a wide range.

A second silver halide complexing agent, such as PMT (i.e. l-
If phenyl-5-mercaptotetrazole) or 6-benzylaminopurine is initially present in the image-receiving layer, the higher concentration required if the silver halide solvent is placed first in the processing composition. The complexing agent will be coated per area.

A second silver halide complexing agent can be present initially as a fraction of the processing composition, in which case the complexing agent is present by penetration into the silver halide layer as soon as the processing composition is applied. It should be noted that it can be used too quickly.

This is true even for strong complexing agents such as 1-phenyl-5-mercaptotetrasol, and this complexing agent is generally removed at a later date to prevent it from being utilized too quickly. The silver halide is first placed on the image-receiving element so as to reach it.

Particularly when this mercaptotetrazole in the processing composition is kept at low temperatures, it is expected to reduce the control of dye transfer.

The use of 6-alkylaminopurines, including the preferred 6-benzylaminopurines, gives particularly good sensitometric results in dye developer transfer processes over a very wide temperature range.

It has therefore been found that a constant concentration of 6-benzylamino-purine gives better sensitometric results over a wider temperature range than a constant concentration of mercaptans such as PMT.

It will be appreciated that a dye transfer image that is neutral or black instead of multicolored can be obtained by the use of a mixture of dyes of suitable color, and that this transfer is controlled by a single layer of silver halide according to known techniques. .

It will also be understood that "direct positive" silver halide emulsions may be used depending on the particular dye image-providing material used and whether positive or negative color transfer is desired.

In the use of certain dye image-providing materials, the precipitation of silver by reduction by the silver precipitate layer on the one hand produces reaction products by its oxidation, such as oxidized developer, which oxidizes the other when reduced; It will be appreciated that the specific dyes mentioned above react with the image-providing materials to produce diffusible image dyes or image dye intermediates.

This undesirable dye concentration due to dye transfer in the transferred image is avoided by the provision of a substance (scavenger) which scavenges this reaction product between the silver precipitant layer and the image dye supply material.

Thus, when the reaction product is an oxidized developer, a non-diffusible reducing agent disposed between the silver precipitate layer and the dye-image-providing material is used as a scavenger to convert the oxidized developer into a dye-image-providing material. This reduces the oxidized developer before it enters the reaction which diffuses the undesirable dye.

In those embodiments where this step is performed outside a dark room, a layer of silver deposited on the silver precipitate layer helps provide the necessary opacification.

In particular, the opacity provided by the silver layer thus created helps the optical filter release color at a faster rate.

It is within the scope of this invention to use one or two support layers of polymeric or other materials that transmit water vapor at a rate suitable to dry the laminate quickly.

Suitable supports of this type are described, for example, in U.S. Pat.
73044.

It will be apparent from the foregoing that the present invention exhibits a significant reduction in the tendency of negative-positive color reflection prints with diffusion transfer to exhibit highlight fading from photolytic degradation of unreduced silver ions present in the dye image layer.

All materials included in the foregoing description are included by way of example and not in a limiting sense, as some changes may be made in the products and methods described above without departing from the scope of the invention contained herein. It is something that can be understood.

[Brief explanation of the drawing]

FIG. 1 is a schematic enlarged view of a diffusion transfer dye image formed in accordance with one embodiment of the invention, and FIG. 2 is a similar schematic illustration of a diffusion transfer dye image formed in accordance with another embodiment of the invention. It is an illustration.

Claims (1)

[Scope of Claims] 1. Contains layers forming a laminate or comprising layers capable of being combined with each other to form a laminate, and the laminate, in sequence and in superimposed relationship, is transparent. a support layer, an image-receiving layer, and an image-providing substance which, depending on the degree of development, provides an image-wise distribution of color-providing substance which diffuses into said image-receiving layer to form a color image-providing substance; In a diffusion transfer photosensitive photographic film unit for forming an integral negative-positive reflective print in color by diffusion transfer, the film unit comprises at least one silver halide emulsion layer having in combination (capable of forming a transferred image) ( a) said film unit comprises: (1) a layer of silver precipitant between said image-receiving layer and said silver halide emulsion layer; and (11) a processing composition so as to form said reflective print after exposure of said film unit. (b) the film unit also includes a light-reflecting material between the image-receiving layer and the layer of silver precipitant; the treatment composition in the rupturable container, the rupturable container comprising a reflective layer or the rupturable container being adapted to release its contents between the layer of silver precipitant and the image-receiving layer; (e) the film unit also comprises a silver halide solvent capable of forming a soluble silver complex (the silver halide solvent is present in the treatment in the breakable container); composition and/or contained in an image-receiving layer).