JPS5947303B2 - Image-receiving element and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Methods for producing silver photographic images by diffusion transfer are well known in the art.

To form a positive silver image, the latent image contained in the exposed light-sensitive silver halide emulsion is developed, and thereupon, substantially simultaneously, a silver halide solvent and the silver halide of the unexposed, undeveloped emulsion are combined. A soluble silver complex is produced by reaction with The light-sensitive silver halide emulsion can be developed under various conditions with a processing composition spread between a light-sensitive element comprising the silver halide emulsion and a print-receiving element preferably comprising a suitable silver precipitate layer. is preferred. The processing composition effects the development of the latent image in the emulsion, substantially simultaneously forming a soluble silver complex compound, such as a thiosulfate or thiocyanate, with the undeveloped silver halide. This soluble silver complex is at least partially transported towards the print-receiving element and most of the silver is precipitated in the silver precipitate layer forming a positive image thereon. This method described is
For example, Edwin H.La
No. 2,543,181 issued to ND). In addition, "One Step Photography" by Edwin H.
hOtOgraphy-PhOtOgraphicJO
urnal2SectiOnA), 7ゝ15 pages (195
(January 0). Additive reproduction involves exposing a light-sensitive silver halide emulsion through an additive screen having a filter medium or screen element for each individual additive color, such as red or green or also blue, and then exposing the light-sensitive silver halide emulsion to light through an additive screen having a filter medium or screen element for each individual additive color, such as red or green or also blue. It can be produced by viewing the formed reversal or positive silver image transferred to a transparent print-receiving element through the same or similar screen which suitably imprints the carried reversal positive image.

Examples of film structures suitable for use in additive photography include U.S. Pat. No. 2,861,885;
No. 4; No. 2944894; No. 3536488;
Same No. 3615427; Same No. 3615428: Same No. 3
No. 615429; No. 3615426: and No. 3
No. 894871 can be mentioned. The image-receiving element of the invention contains in particular a positive transfer image and a negative silver image;
These two images are present in separate layers on a conventional transparent support and are suitable for use in diffusion transfer film units where they can be viewed as a single positive image.

Such a positive image is called an ``integrated positive-negative image'' (I
ntegralpOsitive-Negativei
images) and more particularly ``Integral Positive-Negative Transparencies''.
vetransparencies). An example of a film unit providing such an integrated positive-negative transparency is, for example, U.S. Pat. No. 3,536, cited above.
No. 488; No. 3894871; No. 3615426
No. 3615427; No. 3615428; and No. 3615429. in general,
The silver precipitation nucleus consists of a special class of auxiliaries well known in the art as being suitable for carrying out the catalytic reduction of solubilized silver halides, in particular metals of groups 1B1, B, A, A and 1B, HB, A and the reaction products of Group A metals and Group A elements.

A widely used silver precipitation nucleus is U.S. Patent No. 269.
No. 8237 and specifically includes metal sulfides and selenides, and these terms include selenium sulfides, polysulfides and polyselenides as detailed in that patent. be understood.

Preference is given to using salts of sulfides, especially zinc, whose solubility varies from 10@-3 to 10@-23 occurring at about 20 DEG C. in aqueous media. Heavy metals such as silver, gold, platinum, palladium, etc. are also particularly suitable as precipitants, and within this category the exemplified noble metals are preferred and are generally provided as colloidal particles in a silica matrix. The nucleation layer in this technology is generally about 1 micron (approximately 9.3η
/ square foot).

For example, U.S. Pat.
See No. 09687. U.S. Pat. No. 3,647,440, issued March 7, 1972, discloses a method for reducing precious metal salts obtained by reducing a noble metal salt with a reducing agent having a negative standard potential greater than -0.30 in the presence of a colloid or binder material. A receptor layer consisting of fine non-silver precious metal nuclei is described.

To obtain nuclei with a particular usable size range,
It is the essence of this patent to use a reducing agent with a negative standard potential greater than -0.30. The patent further explains that stannous chloride outside this standard potential range will not produce useful nuclei. Binder materials listed include gelatin, polyvinylpyrrolidone, copoly(2
monochloroethyl methacrylate (acrylic acid), a mixture of polyvinyl alcohol and a copolymer of n-butyl acrylate, 3-acryloyloxypropane-1-sulfonic acid sodium salt and 2-acetoacetoxyethyl methacrylate, polyethylene latex. and colloidal silica.
The amount of colloidal binder used is about 5 to 500 W, with the amount ranging from 1 to 200 micrograms/square foot! 9/square foot. In accordance with the present invention, a new silver precipitation nucleus system has now been discovered which has advantages not found in the prior art, and which is particularly useful for silver transfer color images. The present invention relates to a receiving element for use in an additive diffusion transfer process, which element comprises an additive screen and a transparent support carrying a layer of precious metal nuclei and polymer. The core is about 0.1 to 0.3T
f19/ft2, and the polymer is present at about 0.5 to 5 times the coverage of the core. Therefore, the total amount of core and polymer is no more than about 2 to 1/2 square feet. In a preferred embodiment, the noble metal core consists of a palladium core.

In a particularly preferred embodiment, the noble metal core is produced by reducing a noble metal salt or complex, more preferably with a possible bivalent first metal. The silver precipitated layer used in the novel receiving element according to the present invention provides a positive silver transfer image with coverage not previously used or taught by the prior art.

A relatively thin nucleation layer and a small number of nuclei and relatively low polymer content are not only unexpected from the point of view of the prior art, but also not obvious. Generally, a large excess of polymer or other binder to the core was used. Noble metals used in the present invention include silver, gold, palladium and platinum.

However, particularly good results have been achieved by using palladium in a specific coverage range and therefore, for convenience, the invention will be described primarily with respect to this preferred embodiment. Excellent photographic results are obtained when palladium metal nuclei are used in gelatin or hydroxyethyl cellulose polymers, especially with regard to tone and density of the silver image. The amount of precious metal core may be varied over the ranges suggested, but particularly advantageous results are obtained at a level of about 0.15 to 0.25/sq. ft., more particularly about 0.2 W9/sq. ft. .

In a preferred embodiment, the polymer has a coverage of about 0% of the noble metal core.
．． Use at 5 to 5 times the level.

The ability to use very small amounts of such polymers without causing precipitation or settling of the precious metal nuclei, and at the same time to obtain desirable sensitivities and, in particular, desirable silver image tones, is well known in the art. This is surprising considering common sense. Furthermore, gelatin is more neutral when used at lower polymer ranges.
al) image tones are achieved. Preferably, the noble metal core is obtained by reduction of a noble metal salt or complex compound.

In a preferred embodiment, the reduction is carried out with a first metal or reducing metal that can exist in two valence states. Without intending to be bound by theory, it is believed in the art that noble metal ions are reduced to a metallic state that can serve as catalytic sites for silver deposition in diffusion transfer processes. Accordingly, the term "noble metal core" encompasses metallic noble metals in colloidal form as well as alloys with other substances, such as said first metals, and the terms "reduce" and "reduced" refer thereto. It thus refers to a chemical reaction that results in the colloidal or alloyed formation of metals. The precious metal core is substantially in the form of a metal or alloy,
It should be understood that small amounts of noble metal complex compounds may be present. Examples of substances suitable for use as first metal ions include iron, cobalt, nickel, bismuth, lead, titanium, vanadium, chromium, copper, molybdenum, antimony, tungsten and suitable tin. Noble metal cores prepared by the method described in Pending Patent Application No. 699,202, filed January 14, 1976, may also be used in the receiving element of the present invention.

As used herein, the term "polymer" includes natural and synthetic polymers and includes the following: gelatin methyl cellulose carboxymethyl cellulose sodium salt hydroxy methyl cellulose hydroxy ethyl cellulose hydroxypropyl cellulose carboxymethyl hydroxy ethyl cellulose arginine Acid Sodium Salt Agarose Polyvinyl Alcohol Deacetylated Chitin In some cases, successive coatings of noble metal nucleation layers separated by layers of deacetylated chitin or a suitable polymeric binder such as gelatin may be used.

However, in a preferred embodiment, a single layer of noble metal/polymeric silver precipitate layer is coated. When used in a silver diffusion transfer process, the novel image-receiving element of the present invention forms a positive silver image thereon, which is believed to be a result of the relatively thin nucleation layer used, due to the uniformity of the image silver. It is often characterized by mirror-like deposits.

This positive silver is denser than that generally found in prior art image-receiving elements and has properties similar to those obtained with vacuum deposited silver, which is believed to be the densest form possible. The mirror effect described above is particularly desirable in transparencies, since it tends to increase the Dmax of the projected image when the mirror is on one side of the support closest to the projected light. The absorption spectrum of the silver transfer image is relatively neutral, ie, similar to vacuum deposited silver. Thus, the present invention allows the production of thin, tightly packed matrices of nuclei in which the image silver deposited resembles vacuum deposited silver. Combinations of precious metals can be used as well as single precious metals. In a preferred embodiment, a noble metal salt or complex compound can be reacted with a reducing metal salt from an aqueous salt of the noble metal. Suitable compounds include the following compounds: The ratio of first metal salt to noble metal salt or complex compound can range from about 1:1 to 4:1, preferably 3:1 (this ratio is based on the weight of the metal). based on).

U.S. Pat. No. 3,647, cited earlier herein.
The silver precipitate layer of No. 440 has nuclei of approximately 1 to 200 μ9/Ft2 (
0.001~0.2η/Ft2), and the amount range of the binder in the precipitated layer is 5.0~500.0w.
! f/Ft2. Therefore, in the above US patent, the amount of nuclei per area of the silver precipitated layer overlaps with the amount of nuclei per area of the silver precipitated layer of the present invention, but the amount of nuclei per fixed amount of binder is the same as that of the above US patent. The largest amount is one or less of the smallest amount of the present invention. Therefore, the silver precipitated layer of the above-mentioned US patent cannot have a very high nucleus density as in the present invention.
Higher nuclear density results in higher silver image density. In the present invention, the silver precipitate layer is made much thinner than conventional ones, and the nucleus density is increased, so that a silver image density similar to that of vacuum-deposited silver can be obtained. In the present invention, the coating amount of the silver precipitate layer is not more than 2.0~/Ft2, in fact it is at most 1.87r1f/Ft2, but the silver precipitate layer in the above US patent has a coverage of at least 5.0η/Ft2. . Therefore, the silver precipitate layer in the above-mentioned US patent is much thicker than that of the present invention, and the nuclear density is much smaller than that of the present invention, so that image silver that is close to vacuum-deposited silver as in the present invention cannot be obtained. . Therefore, even if the invention of the above-mentioned US patent is used in the present invention, the desired mirror effect cannot be obtained. The essence of the present invention and the advantages obtained therefrom is that it provides a very thin positive image-receiving layer that is thinner than suggested in the art to obtain a mirror effect from deposited silver.

As previously explained, mirror effects are particularly desirable in photographic transparencies because they tend to increase density in the projected image. The absorption spectrum of the silver transfer image is relatively neutral, ie, similar to vacuum deposited silver.
The following non-limiting example illustrates the novel method of the present invention. Example 1 The following solutions were prepared: Solution A K2PdCl4 is dissolved in water and hydroxyethylcellulose and surface agent are added to this solution.

Add solution BSnCl2 to water and add hydroxyethylcellulose and surface agent to this mixture.

Solutions A and B are mixed rapidly together, stirred for 30-60 minutes, and then coated onto a suitable support for use as a silver deposit layer.

A method of utilizing such a nuclear layer will be described below.

Example 2 Additive screen with approximately 1000 Ξ sheets per inch of red, positive and green filter screen elements in repeating parallel relationship on one side; 4 micron polyvinylidene chloride-polyvinyl formal protective overcoat; over this protective layer Slot-coated nucleating material prepared by the method of Example 1; 10% inert gel solution 26θ was added to 72cc of water, heated to 39°C, mixed until homogeneous, then octylphenoxypolyethyl A gel coating (50Tf) made by adding 3CC of a 1% solution of ethanol surface agent
Propylene glycol alginate with a coverage of about 115 Tf7/ft2 of gelatin and about 100 Tn9/ft2 of silver;
8 mf7/sq ft and 5,5'-dimethyl-
9-Ethyl-3,3'-bis-(3-sulfopropyl)thiocarbocyanine triethyl-ammonium salt; 5,5-diphenyl-9-ethyl-3,3'-bis-(4-sulfobutyl)oxacarbocyanine a hardened gelatinoiodine silver chloride emulsion coated with about 0.45 mf/sq ft of sodium dioctyl sulfosuccinate panchromatically sensitized with; and a clear polyester film having an antihalation (AntihalO) surface coating as described below. A film unit consisting of a base was produced.

The antihalation surface coating cited below is patent application No. 38326 under examination, filed July 27, 1973.
It is described and claimed in No. 1. A 3.0 mil gap mechanical rub roller (1aBr
Ollers).

The film unit was kept in the dark for 1 minute and its neutral column was read for white, red, green and blue light on an automatic recording densitometer.
Treatment Composition A Ingredients in the indicated proportions of film units within the scope of the present invention;
The surface coatings and treatment compositions were prepared and treated according to the methods of Examples 1 and 2.

Example 8 The following solutions were prepared: The solution is stirred at about 40°C.

Boiled to form nuclei.

Solution A2O9 was added and 15 minutes later solution B59 was added.
The mixture was boiled again and then stirred vigorously while adding solution C2O9. After stirring for an additional 15 minutes, the mixture was allowed to cool to room temperature within 5 minutes. Next, the total amount is 1909
Add enough water to cover. As a coating aid, 0.1%
Alkyl phenoxypolyoxyethylene ethanol surface agent (Diamond Jamrock's NOPCO
(sold under the trade name PE-120 by Kemi, Devi, Inc.) was added. Alternatively, the nuclei are formed at room temperature. To distinguish the difference between this process change, the nuclei formed at high temperature are referred to as "HOT", while the nuclei formed at room temperature are referred to as Example 9 with a gel layer between the receiving layer and the emulsion layer. A film unit was prepared according to the method of Example 2, except that the copper-chitin layer prepared in Example 2 was replaced.

A solution consisting of

The solution thus formed was coated to form a layer of 7.about./sq.ft.

The copper-chitin layer is claimed in US Pat. No. 4,056,392.

Film units within the scope of this invention were prepared according to the method of Examples 8 and 9 and then treated according to the method of Example 2 using the component proportions, surface coatings, and treatment compositions indicated.

Processing Composition C The following table shows the photographic results obtained when the cores prepared according to Example 8 were combined with film units prepared according to the method of Example 9 and processed according to the method of Example 9. The amount of precious metal core is varied.

Examples 16 and 17 used Treatment Composition D and Surface Coating D.

EXAMPLE 18 Cores were prepared according to the method of Example 8 and combined into a film unit according to the method of Example except that the copper-chitin layer was used in the same amount as the copper-gelatin layer.

Palladium coverage of 0.2~/sq ft and 1:
At a gelatin/palladium ratio of 1, the following transmission densities were obtained for this film unit:

Treatment Composition D and Surface Coating D were used.

Example 19 Nuclei were prepared according to the method of Example 8, except that potassium palladium tetrachloride was used instead of palladium chloride.

This core was assembled with a film unit according to the method of Example 9.
Palladium coverage of 0.2W9/ft2 and 1
The following transmission densities were obtained at a gelatin to palladium ratio of 1:1.

Treatment Composition D and Surface Coating D were used.

Example 20 The method of Example 8 was modified by using 0.2359 sodium hypophosphite in 100 fl of water instead of the stannous chloride reducing agent. Example 21 Instead of the stannous chloride reducing agent, water Example 8 by using 0.0849 sodium borohydride in 100y
The method was modified.

Nuclei prepared using these reducing agents were combined with the film units described in Example 9 and processed to give the following results. Treatment Composition E and Surface Coating E were used.

As mentioned above, the preferred polymer for use in the receiving layer of the present invention comprises gelatin. Gelatin can be used at the lower limit of the core-binder ratio to give a good density neutral-toned positive image in the receiving layer, while a suitable amount of other polymers such as hydroxyethyl cellulose can be used at the lower end of the core-binder ratio. High binder ratio range. In another embodiment, the colloid formed by reduction of the noble metal salt or complex compound is dialyzed prior to coating.

The effect of this dialysis is to impart increased stability to the coating composition. Without wishing to be bound by theory, it is believed that this increased stability is a result of the increased pH and (or the removal of certain ions such as H, K and Cl).

In yet another embodiment, the pH of the colloid is changed from acid to alkaline to cause precipitation of the precious metal.

This precipitate is then separated, washed and redispersed in the polymer,
Then cover. This removes any unwanted by-products or raw materials. The particle size of the silver precipitation nuclei of the present invention can vary over a relatively wide range.

In preferred embodiments, the core ranges from about 15A to about 65A. For example, the nuclei produced according to the method of Example 1 are 1
It has an average diameter of approximately 20A, with 80% of particles having a diameter of 17A to 40λ, measured on 000 particles. The nuclei prepared according to Example 8 were 19λ to 4 when measured on 1000 particles.
It has an average diameter of about 31A, containing 80% of particles with a diameter of 6λ. The support used in this invention is not critical.

The film-based support used can be of any of a variety of types of transparent rigid or flexible supports, such as glass, polymeric films, both synthetic and those derived from natural sources, and the like. However, particularly suitable materials are polymethacrylic acid methyl ethyl ester;
Vinyl chloride polymers; polyamides such as polyvinyl acetal nylon; polyesters such as polymer films derived from glycol terephthalic acid; cellulose acetate, triacetate, nitrate, propionate, butyrate, acetate;
It consists of polymeric cellulose derivatives such as butyrate or acetate-propionate; flexible transparent synthetic polymers such as polycarbonate; polystyrene, etc.

The additive screens used in the present invention may be formed by sequentially printing the required filter pattern using techniques well known in the art, such as photolithography.

An additive screen usually consists of a set of colored surfaces or an array of filter elements of two to four different colors, each of the set of colored surfaces transmitting visible light within a predetermined wavelength. It's watery. In the most common situation, additive screens are trichromatic, with one element of each set of color filters transmitting light in one of the so-called primary color wavelengths, eg red, green and blue. The colored screen may consist of finely colored particles, such as starch granules or hardened gelatin granules, which are mixed and dispersed in a regularly or irregularly arranged arrangement to form a mosaic. This type of regular mosaic can be created by the EmbOssing and alternating blending techniques described in US Pat. No. 3,019,124. Another method of forming a suitable color screen is described in U.S. Pat. No. 3,032,008.
The process consists of a multi-wire extrusion process of the type described in 1996, in which fine colored wires are deposited in parallel in a single coating operation.

Yet another method is described in US Pat. No. 3,284,208. Silver halide solvents useful for forming the desired soluble complexes with unexposed silver are well known and can be selected, for example, from alkali metal thiosulfates, particularly sodium or potassium thiosulfates.

Alternatively, silver halide solvents can be manufactured by WinH. It can be a cyclic imide such as uracil in combination with a nitrogen base, as taught in U.S. Pat. No. 2,857,274 issued October 21, 1958 to Rand.

Although the silver halide solvent is preferably present initially in the processing composition, the silver halide solvent is contacted with the layer of the film unit, preferably with an alkaline processing fluid, to release or generate the silver halide solvent. It is also within the scope of the invention to initially place it in the form of a precursor. The treatment composition may contain a thickening agent such as alkali metal carboxymethyl cellulose or hydroxyethyl cellulose in an amount and viscosity suitable for easy application of the treatment composition. The processing composition may remain on the processed film or may be removed by known techniques, as appropriate for the particular film application. The necessary alkalinity, e.g. a pH of 12-14, is preferably imparted to the treatment composition with materials such as sodium, potassium and/or lithium hydroxide. Wetting agents may be advantageously included in the treatment composition to facilitate its application, particularly when the treatment composition is applied as a very thin layer of a low viscosity fluid. Suitable silver halide developers can be selected from those known in the art and can be initially placed in the photosensitive element and/or processing composition.

Claims (1)

[Scope of Claims] 1. Consisting essentially of a transparent support carrying in order an additive color screen, a silver precipitation layer containing noble metal precipitation nuclei and a polymer, and a light-sensitive silver halide emulsion layer, and further comprising: Nuclei are present at levels of 0.1-0.3 mg/sq ft;
The polymer is present at a level of about 0.5 to 5 times the amount of the nuclei used, the silver precipitate layer is no more than about 2 mg/ft^2, and the silver precipitate layer contains silver precipitate nuclei. An additive diffusion transfer film unit characterized by being the only layer. 2. The film unit according to claim 1, wherein the core is obtained by reduction of a noble metal salt or a complex compound. 3. A film unit according to claim 2, wherein the reduction is carried out with a first metal which can be in two valence states. 4. A film unit according to claim 1, wherein the nuclei are present at a level of about 0.2 mg/ft^2. 5. The film unit according to claim 1, wherein the polymer is gelatin. 6. The film unit according to claim 1, wherein the polymer is hydroxyethylcellulose. 7. A film unit according to claim 1, wherein the polymer is present in an amount about 1 times the amount of the core. 8. The film unit of claim 5, wherein the nuclei are present at a level of about 0.2 mg/ft^2. 9. The film unit according to claim 1, wherein the noble metal is palladium. 10. The film unit according to claim 3, wherein the first metal is tin. 11. The film unit of claim 10, wherein the noble metal salt is palladium chloride and the first metal is provided by stannous chloride. 12 Claim 1 including an anti-halation layer
Film units listed in section.