US3819379A - Silver halide photographic material for use in color photography - Google Patents

Abstract

A multilayer silver halide photographic material for color photography comprising silver halide photographic emulsion layers and auxiliary layers containing no silver halide emulsion, wherein either the emulsion layers or the auxiliary layers contain an anionic development inhibitor such as sodium 2mercapto-3-ethyl-benzimidazole-6-sulfonate in the form of a complex with a cationic polymer such as a benzyl chloride salt of a dimethylaminoethanol ester of polymethacrylic acid. In alkalinity, the inhibitor is instantly released from the complex and acts to inhibit the formation of development fog sufficiently.

Description

[45] June 25, 1974 1 SILVER HALIDE PHOTOGRAPHIC MATERIAL FOR USE IN COLOR PHOTOGRAPHY [75] Inventors: Yasushi Ohyama; Hideo Sumitani,

both of Kyoto, Japan 73 Assignee: Mitsubishi Paper Mills, Ltd., Tokyo,

Japan [22] Filed: Jan. 18, 1973 [21] Appl. No.: 324,708

[30] Foreign Application Priority Data 8/1971 Tuites et a1. .L 96/109 8/1971 Tuites et a1. 96/109 Primary Examiner-Ronald H. Smith Assistant Examiner-Alfonso T. Suro Pico Attorney, Agent, or Firm-Sughrue, Rothwell, Mion, Zinn & Macpeak [57] ABSTRACT A multilayer silver halide photographic material for color photography comprising silver halide photographic emulsion layers and auxiliary layers containing no silver halide emulsion, wherein either the emulsion layers or the auxiliary layers contain an anionic development inhibitor such as sodium 2-mercapto-3-ethylbenzimidazole-6-sulfonate in the form of a complex with a cationic polymer such as a benzyl chloride salt of a dimethylaminoethanol ester of polymethacrylic acid. In alkalinity, the inhibitor is instantly released from the complex and acts to inhibit the formation of development fog sufficiently.

4 Claims, 1 Drawing Figure Jan. 20, 1972 Japan 47-7854 [52] US. Cl. 96/68, 96/109, 96/114, 96/1 14.3 [51] Int. Cl G03c l/34, G03c 1/02 [58] Field of Search 96/113, 114, 109, 67, 68, 7 96/74, 114.3

[56] References Cited UNITED STATES PATENTS 3,1 13,026 12/1963 Sprung 961107 5 g Ll- 2-1 '1 2 LOGARITHM 0F EXPQSING AMOUNT (LOG El PAIENTEDJUNZSIBH I 5.819.379

COLOR DENSITY (REFLECTION DENSITY) 5 T d i i 3 LOGARITHM 0F EXPOSING AMOUNT (LOG E) SILVER HALIDE PHOTOGRAPHIC MATERIAL FOR USE IN COLOR PHOTOGRAPHY BACKGROUND OF THE INVENTION pounds containing only nitrogen, such as benzotriazole or benzoimidazole which has'a relatively weak action (of the medium degree), or pyrimidine which has far less desensitizing action, or azaindolizines (generic term for azaindene, diazaindene, triazaindene and tetrazaindene), or their substitution products containing alkyl, phenyl, hydroxyl or amino substituents, both being free from active sulfur. Compounds having active sulfur, especially a mercapto group, such as Z-mercapto-benzoxazole, Z-mercapto-benzothiazole, 2-mercapto-benzimidazole or l-phenyl-S-mercapto-tetrazole, and sulfur-free strong development inhibitors such as -nitrobenzoimidazole may be added to the developer solution, but are hardly added to the emulsion.

However, in the case of silver chlorobromide or silver chloride emulsions which do not have to be concerned so much with a loss in sensitivity and tend to undergo mation' of fog during the progress of ripening. Morelizer are the same substance, and therefore, are generically described as an antifoggant.

Some antifoggants are primarily intended for preventing fog formation during development by addition to a developer solution. Some of such antifoggants can be a ripening inhibitor or stabilizer by addition to the emulsion, ,but many of them cannot be added in suff cient amounts to the emulsion because of their strong adsorptive property to the silver halides to give adverse effects such as marked impairment of development or destruction of the sensitivity speck which will result in marked desensitization. In this sense, these antifoggants may sometimes be referred to as a development inhibitor with a view to distinguishing it from the ripening inhibitor.

Besides these, there are other additives such as a development accelerator, a blue black additive for developrnent, a blue black toner, or a discoloration inhibitor (anti-bronzing agent) for preventing the photographic material from turning brown to violet brown as a result of a heat treatment such as ferrotype (this phenomenon is referred to as bronzing), but they will not be described in this specification. Some of them, however, act concurrently as a development accelerator, development inhibitor or stabilizer, and therefore will bede scribed at some length below in order to avoid any confusion.

In the early stage of the development of the ripening inhibitor or development inhibitor, the photographic materials were limited to use in black-and-white photography, and natural products such as quinine, cystine or a condensation product formed between cystine and formalin or processed products thereof were frequently used. By and by, these natural products were superseded by synthetic heterocyclic compounds such as benzimidazole, benzotriazole or thiodiazole. Silver iodobromide emulsions for high speed negatives are inherently slow in development and require a high degree of sensitivity, not permitting even slight desensitization. Therefore, as an additive for the silver iodobromide emulsions, there are generally used heterocyclic comfog formation because of 'a fast rate of development, these sulfur-containing strong antifoggants are usually added also to the emulsions in suitable amounts together with such inhibitors as benzotriazole or benzimidazole having a medium degree of activity. The addition of these inhibitors is essential especially in emulsions for photographic paper having excellent sensitivity and developability which has recently come into use.

Since these antifoggants having medium to strong activity tend to adsorb strongly to the surfaces of the silver halide grains and to check the adsorption of sensitizing dyes, it is almost impossible, except for some special instances, to incorporate them directly into photographic paper emulsions to be color sensitized, especially into emulsions for color photography. Measures are taken to prevent this effect on the emulsion layer to the utmost extent by incorporating them into an interlayer, substratum, over layer, etc. In this case also, the antifoggant diffuses into the emulsion layer in the coating and drying steps, and because the extent of diffusion is liable to change according to the conditions, it is difficult to obtain constant results. Thus, small amounts of benzotriazole or benzimidazole which has a relatively small effect is directly added to the emulsion. Or in recent years, a development inhibitor obtained by introducing a sulfonic acid group or carboxylic acid group into the molecules of such a mercaptocontaining strong additive to render it anionic has been added in a small amount. It is reported in O. Riester: Photo. Sci. & Eng. 13, 13 (1969) that by the introduction of anionic groups, the adsorption of the antifoggant to silver halide grains is weakened, and the so modified antifoggant forms an electrical complex with a cationic substance such as cyanines or merocyanines which are typical sensitizing dyes, and that such a complex does not expel the sensitizing dye out of the surface of the silver halide grains but acts as a supersensitizing agent. It appears however that such modified antifoggants do not effectively act on all sensitizing dyes. Generally, they are effective on red-sensitive emulsions, butact considerably desensitizingly on greensensitive emulsions, blue-sensitive emulsions, and emulsions not color sensitized. Therefore, their use is limited. These modified antifoggants can be used conveniently to some extent for color photographic paper,

course of development, it is allowed to release a free inhibitor which acts as a development inhibitor. For example, such a precursor is the DIR coupler (development inhibitor releasing coupler) disclosed in Japanese Pat. Publication No. 21778/68 or the development inhibitor releasing compound disclosed in Japanese Pat. Publication No. 22514/71. When color development is performed to form an oxidation intermediate of a color developing agent, the DIR coupler couples with it to form a dye and simultaneously releases a development inhibitor, and the development inhibitor releasing compound forms a colorless compound with the oxidation intermediate and simultaneously releases a development inhibitor. Since the inhibition of development is strong at the part where development is vigorously performed, these proposals have great effects for soft gradation. But they have the defect that at the part where development is hardly performed, for example, at the white background of photographic paper corresponding to the foot of the characteristic curve, fog can hardly be inhibited.

The antifoggant precursor disclosed in US. Pat. No. 3,575,699 is a substance obtained by substituting a benzoyl group for an active group of an antifoggant of the benzimidazole, benzotriazole or 4 -azabenzimidazole type, which is stable in an acidic or neutral condition, but is hydrolyzed in a strongly alkaline developer solution to release a development inhibitor. Thus, this precursor is effective irrespective of the amount of exposure or the amount of developed silver. Although having a small effect for soft gradation, it has the property of inhibiting fog well at the portion having a small amount of exposure or unexposed portions, which correspond to the foot of the characteristic curve. It is however clear that the choice of such a compound which can be sufficiently hydrolyzed within a short period of time after encountering alkali (in recent practice, development frequently ends within as short as 30 seconds to about I minute) and which is stable at the pH of the emulsion (especially in the presence of a great quantity of water at the time of coating and under the temperature and time conditions employed during the coating procedure) is very much limited, and it is difficult to inactivate the inhibitor as desired.

SUMMARY OF THE INVENTION Accordingly, it is an object of this invention to provide a multilayer silver halide photographic material for use in color photography comprising silver halide photographic emulsion layers and auxiliary layers containing no silver halide emulsion, both layers being coated in a superposed relationship; wherein either the emulsion layers or the auxiliary layers contain an anionic development inhibitor in the form of a complex with a cationic polymer.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS FIGURE is the characteristic curves showing the relationship between the magenta color density and the amount of exposure determined after stepwise exposure of the photosensitive materials (a), (b) and prepared in Example 1.

DETAILED DESCRIPTION OF THE INVENTION The characteristic feature of this invention is that an anionic development inhibitor in the form of a complex with a cationic polymer is incorporated into a silver halide emulsion layer of a multilayer photographic material for color photography or an auxiliary layer such as a substratum layer, interlayer or over layer to be coated in a superposed relation with the emulsion layer. The invention is applicable to any type of development inhibitor containing a sulfonic acid group or carboxylic acid group. The cationic polymer, which is to be described in detail, may be a vinyl polymer containing an ammonium salt, pyridinium salt, piperidium salt or morpholium salt, or aminoguanido-dialdehyde starch, which have been used widely as a mordanting agent for acid dyes, an electrically conductive paint, or

a flocculating agent for contaminated water, etc. This' cationic polymer has a number of cationic groups in the molecule and has a great power of attracting an anionic sulfonic acid group or carboxylic acid group to these cationic groups by an electrical affinity and retain it therein. Direct dyes, acid dyes or fluorescent brightening agents whose trunk molecule has a relatively large molecular weight and contains two or more sulfonic acid or carboxylic acid groups have very great complex bonding force, and generally, the bonding is complete even in an alkaline condition. However, as will be described in greater detail, the anionic development inhibitors generally have a small molecular weight, and many of them have only one anionic group. Therefore, they have poor ability to form complexes with cationic polymers. In acidity or neutrality, they are well bonded within the complexes, but in alkalinity, the anionic development inhibitors readily diffuse in a free form. Since the inhibitor is completely bonded with the cationic polymer during the coating and drying of an acidic or neutral multilayer emulsion or within the raw photographic material before development, the anionic development inhibitor is completely bonded to the cationic polymer, and does not give adverse effects such as desensitization by adsorption to the surfaces of silver halide grains. When it enters a developer solution and absorbs an alkaline aqueous solution, it is immediately released from the complex, and diffuses freely as a development inhibitor to inhibit the formation of development fog sufficiently.

The anionic development inhibitor to be used in the present invention is obtained by introducing a carboxylic acid group (-COOH), sulfonic acid group (-SO H) or sulfinic acid group (-SO H) into the molecules of a known development inhibitor, the examples of which range from the strongest development inhibitors comprising nitrogen-containing heterocyclic compounds into which a free mercapto group has been introduced to inhibitors having a medium degree of activity which contain hydrogen of an imino group (-NH-) as an active hydrogen. These anionic groups are free in acidity, but in neutrality or alkalinity, they form an alkali metal salt such as a sodium salt or potassium salt or an ammonium salt, dissociating in aqueous solution to exhibit anionic properties in general. The heterocyclic compounds which form a basis of the inhibitors are in many cases substituted with a hydroxyl group, amino group, halogen atom such as chlorine, bromine or fluorine, nitro group, alkyl group, aryl group or aralkyl group. Typical examples of the heterocyclic compounds which permit easy introduction of anionic groups are shown below together with their structural formulae which will follow.

(1) Sodium benzotriazole-5-sulfonate (ll) Sodium benzimidazoIe-S-sulfonate (Ill) Sodium Z-methyl-benzimidazole-5-sulfinate (IV) Thiazolidine-4-carboxylic acid (V) Z-Phenyl-thiazolidine-4-carboxylic acid (VI) l,5-Di(o-sulfophenyl)-s-triazolidino-( l ,2-a)-striazolidine-3.7-dithione (VII) 2-Mercapto-G-sulfobenzimidazole (sodium salt) (VIII) Sodium 2-mercapto-3-ethyl-benzimidazoIe-6- sulfonate (IX) 2-Mercapto-S-sulfobenzothiazole (sodium salt) (X) 2-Mercapto-benzoxazoIe-S-carboxylic acid (XI) Sodium 2-mercapto-S-chloro-benzoxazole-7-sulfonate (XII) Sodium Z-mercapto-I', 8'-naphthoxazole-6'-sulfonate (XIII) l-(m-Sulfophenyl)-5-mercapto-tetrazole (XIV) 2-Mercapto-4-(p-carboxyphenyl)- I ,3,4-thiodiazole- S-thione N N NaO s N80 s N/ N (1) H (11 H N\ mtg-alpaca: NaO S NH -CH5 c \N H: (III) E 1 (IV) mc-- Jn-ooo11 l NE a s l -o1 1-r \NH HN\ /N--t JH N501 C SO Na W) l Naons I SH N \N t v11 H more l 0 I (XII) BO3NB (XII) (XIV) The cationic polymers used in the present invention are commercially available vinyl polymers for use as a flocculating agent for contaminated water, an antistatic agent for plastic films or paper or an electrically conductive paint, or natural polymer products such as i starch or cellulose. They also find utility as a mordanting agent for acid dyes. Many of them are available commercially. Some commercially available polymers are unidentifiable, but are not so much different from others.

Examples of the cationic polymers useful in this in- ;vention are:

The structural formulae of these polymers are shown schematically below.

CHaOH Polymer (a) is not converted to a quaternary salt, and polymer (b) is a quaternary salt. All of these polymers may or may not be in the form of a quaternary salt, and are useful as such. Furthermore, it is not necessary that all of the polymer units be converted to a quaternary salt. On the other hand, in all of these polymers (a) to (i), a substituent such as an alkyl group or benzyl group to be introduced into nitrogen may be replaced either wholly or in part by another alkyl group, aralkyl group or hydroxyalkyl group. In the case of polymers (1), (m) and (n), a numerous variety of products having different degrees of modification with aminoguanide are possible. Also, a number of varieties can be formed according to the degree of polymerization, or the copolymerization with other vinyl monomers. All of them cannot be exemplified herein, but it is evident that they can also be used conveniently in the present invention.

In the silver halide emulsion layer, interlayer, substratum layer, over layer, etc. into which the complex described above is to be introduced, gelatin is most commonly used as a binder. But in recent years, gelatin has been wholly or in part superseded by a watersoluble hydrophilic binder such as polyvinyl alcohol, polyacrylamide, polyvinyl pyrrolidone, hydroxyalkyl starch, hydroxyalkyl cellulose or carboxymethyl cellulose. Since the above cationic polymers are all watersoluble or hydrophilic (some of them being soluble in alkaline water but insoluble in acidic water), they are well miscible with the binder which constitutes these photographic layers, and can be freely blended therewith. In recent practice, a latex of a water-insoluble soft polymer such as polymers of acrylic acid or methacrylic acid esters or copolymers of such esters with butadiene, styrene or acrylonitrile has been widely used as substance which reduces the shrinking of the photographic layer during drying and impart softness to the dried coating. Therefore, if desired, this additive can also be incorporated.

The silver halide emulsions used in this invention are neither limited to particular species. It is well known to those skilled in the art that according to the type of the emulsion and the purpose of its use, not only is the development inhibitor selected, but also other additives such as a sensitizing dye, coupler, ripening accelerator (or sensitizer) or ripening inhibitor are incorporated. The description of this technique will be omitted since it does not limit the applicable range of the present invention.

The anionic development inhibitor may be directly added to an ordinary acidic or neutral silver halide emulsion if it is weakly bonded with the cationic polymer in accordance with this invention and is diffusible in the free state upon contact with strong alkali in a developer solution. Generally, this causes less side-effects because it can be used in lesser amounts and exhibits quicker activity. However, high speed emulsions have a high pH value and the stability of the complex in such emulsions is questionable. Furthermore, a silver iodobromide emulsion which constitutes the high speed emulsions generally has a low speed of development, and therefore, if the freeing of the development inhibitor is too early, there is a great decrease in sensitivity.

Thusfin this case, it is p referred to incorporate the complex into an adjacent interlayer or substratum layer or into an over layer.

For example, if the complex is added to the substratum of the emulsion layer in high speed negative films for black-and-white photography or high speed monocolor microfilms for color photography, the development inhibitor becomes free only after the photographic material is placed in a developer solution and alkali penetrates into the substratum. Therefore, the inhibitor diffuses slowly from the underside of the emulsion layer, and where exposure is little, the latent image is present mainly near the upper side of the surface of the emulsion layer, and this contributes significantly to the sensitivity of the emulsion. This part is first subjected to the action of the developer solution, and lastly to the action of the inhibitor. On the other hand, where there is great exposure, the light sufficiently reaches the bottom of the emulsion layer, and development must occur vigorously on the underside of the emulsion. But because this part undergoes the influence of the inhibitor earliest and most strongly, moderate inhibition of development is performed without excessive blackening. Development fog which occurs all over the surface irrespective of the amount of exposure is conspicuous where exposure is little, and tends to impair the apparent sensitivity of the emulsion layer. But

,order.

However, in the case of a multilayer color emulsion, if the complex is added only to the substratum layer, the development of the sub layer which is essentially slow in development is retarded all the more. Usually, therefore, the complex is also incorporated into the interlayer to provide an overall balance. Rather, in many cases, the incorporation of the complex in a considerable amount is effective for eliminating excessive development or color fog of the upper layer and the emulsion layer as a result of strong development necessary for rapid processing, and thus balancing the sensitivity and the speed of development among the three layers.

coupler or sensitizing dye to be added to the emulsion differ according to the color tobe formed, yellow, ma

. genta, cyan. Also, the contribution of each emulsion to the overall sensitivity of the photographic material differs, and an emulsion of different inherent sensitivity is used. Consequently, the types and amounts of a sensitizing agent, ripening accelerator and ripening inhibitor to be used in conjunction with the emulsion also differ. Naturally, therefore, the type and amount of the development inhibitor to be incorporated lastly should also be strictly controlled according to the respectivecases. Since the principle is common to all emulsion layers irrespective of the different amounts to be added, some Examples to be given below refer to an emulsion layer of only one color (for example, magenta). It is to be understood that in such a case, the description of other emulsion layers is omitted since it is based on the same principle.

The following Examples illustrate the present invention in greater detail. Naturally, the scope of the present invention will not be limited by these Examples.

(sodium ,benzoylamide-l,2,4-triazoline-5-thione of the following structural formula \N as asensitiaing agent and 2 ml. ofa l percent aqueous solution of S-methyl-6-octyl-7-hydroxy-2,3,4,7atetrazaindene of the following structural formula on N a N N as a ripening inhibitor and then the mature wasrip ened at 60 C. for 60 minutes. Then, 6 ml. of a solution of a sensitizing dye (111000) having a sensitizing maximum at 530 mu, and ml. of a 5 percent aqueous solution of l-( 4-phenoxy-3-sulfo)phenyl-3-octadecyl-5- pyrazolone of the following formula as a magenta-forming diffusion-resistant coupler were successively added, and while adjusting the pH to 6.3, the total amount of the mixture was made 800 ml.

Three portions (each 250 ml.) were taken from the resulting emulsion. Portion (a) was used as a blank, and

t was coated on baryta paper upon addition of ml.

of a 4 percent aqueous solution of gelatin without adding a developmentinhibitor. Portion (b) was mixed with 100 ml. of a 4 percent aqueous solution of gelatin together with 2 ml. of a 1 percent aqueous solution of 2 -mercapto-benzimidazole [the base of compound (VII) mentioned above] as a development inhibitor, and the mixture was coated on baryta paper. Portion (c) was admixed with a solution obtained by mixing 3 ml. of a 1 percent aqueous solution of compound (VIII) 2-mercapto-3-ethyl-benzimidazole-6- sulfonate) with 4 g'of gelatin and a solution of 0.2 g of the cationic polymer (j) in 100 ml. of water, and the mixed solution was coated on baryta paper. (In all cases, the amount of the coating solution coated on baryta paper was adjusted to i 10 g/m After drying, the resulting photographic paper was subjected to stepwise exposure through an optical wedge, developed for 5 minutes at 20 C. with a developer solution of the following formulation, and then subjected by customary methods to stopping fixation, bleaching fixation, hardening, rinsing and drying. The color density (reflection density) of the resulting magenta image was measured, and the results are shown in FIGURE.

Formulation of the developer solution Anhydrous sodium sulfite N-ethyl-Nhydroxyethyl-paraaminoaniline (sulfate) Sodium carbonate monohydrate Sodium hexametaphosphate Potassium bromide Sulfuric acid hydroxylamine Water to make mation. Curve (b) shows the photographic paper obl tained by using the emulsion (b) to which a strong mercapto-containing inhibitor was added. It shows marked desensitization and soft gradation. Since development is retarded, the maximum density is low with the same development time. This is the outcome of impairing the adsorption of the sensitizing dye and inhibiting the development of the portion having inherent sensitivity. Curvetc) shows that as a result of adding a complex formed between the anionic development inhibitor [compound (VIII)] and the cationic polymer [compound (j)] to the emulsion, the above-mentioned impairment of the adsorption of the sensitizing dye and desensitization hardly take place, and fog formation is sufficiently inhibited on a practical basis.

It is usual that strong development inhibitors containing a mercapto group such as exemplified above impede the adsorption of sensitizing dyes. But they can be used on a practical basis if the desensitizing tendency of the inhibitor is minimized by carefully selecting the combination of the dye and the inhibitor and the amount of the inhibitor. In this case also, both of them competitively adsorb to the emulsion, and the adsorption equilibrium is changed by the influence of temperature. Since it is difficult to adjust this influence to the same extent in the same direction with respect to cyan, magenta and yellow emulsions, printing of a long strip of color photographic paper in roll form on a largesized automatic printer in the wintertime, for example, often results in disorder of color balance of the printed photographic paper between early morning and afternoon. When printing is begun in the winter time before the room has been sufficiently warmed, both the paper and the machine are not warmed rapidly, and the temperature of the photographic paper is about C. at the beginning. But by and by, the paper is warmed, and by the time a large quantity of the paper is printed, the temperature of the paper reaches more than C. in conjunction with the heating action of the lamp. This phenomenon is considered to be due to the competitive adsorption of the color sensitizing dye and the development inhibitor (or stabilizer), and can be inhibited almost completely by adding the development inhibitor in accordance with the present invention.

EXAMPLE 2 This Example will illustrate the addition of the complex to an interlayer and an over layer.

On the surface of RC paper (obtained by coating on the surface of a photographic paper a white polyethylene layer containing titanium oxide and a fluorescent brightening agent and on the back surface a transparent colorless polyethylene layer by heat processing), a high speed silver chlorobromide emulsion containing 50 mol percent of silver bromide to which were added 12 a blue-sensitizing dye (sensitized to light of wavelengths not more than 500 mu) and a diffusionresistant yellow-forming coupler was coated as the lowermost emulsion layer. On top of the resulting layer, a solution consisting of a 4 percent aqueous solution of gelatin, 0.2 percent of the cationic polymer (b) (poly- 4-vinyl pyridinium methyl paratoluenesulfonic acid salt), and 0.01 percent of the compound (IX) as a development inhibitor was coated as an interlayer in a superposed relation by an extrusion coater. Then, a coating solution consisting of a silver chlorobromide containing 90 mol percent of silver chloride, a green sensitizing dye having a sensitization maximum at 560 mu and a diffusion-resistant magenta coupler and a coating solution of the same composition as the previous interlayer were coated simultaneously by an extrusion coater, the latter being as an interlayer. Furthermore, on top of the resulting interlayer, a coating solution consisting of a silver chlorobromide emulsion contain- 0 ing 90 mol percent of silver chloride, a red-sensitizing dye having a sensitization maximum at 700 my. and a diffusion-resistant cyan coupler, and a coating solution of the same composition as the above interlayer but containing a twofold amount of the development inhibitor were coated simultaneously by an extrusion coater, the latter being as an over layer. Then, the coatings were dried to form a color paper suitable for making a color print from a color negative. The amount of coating of each emulsion layer was adjusted to ml/m and the amount of coating of the interlayer and the over layer was adjusted to 40 ml/m Each emulsion was sensitized with sulfur by a known method, and at the same time, 5,6-tetramethylene-7- hydroxy-2,3,4,7a-tetrazaindene was added in an amount of 1.5 g per kilogram of silver nitrate as a ripening inhibitor and stabilizer. When the photographic paper obtained in this Example was placed in a developer solution, the development inhibitor contained in the interlayer or over layer diffused upwardly and downwardly. As a result, the lowermost blue-sensitive yellow-forming layer was affected least by the inhibitor, and the uppermost red-sensitive cyan-forming layer was affected most. Thus, the speed of development and the density of color formed were well balanced among the three layers. According to this method, the emulsion layer contained no development inhibitor during the storage of raw photographic paper, and therefore, the azaindolidine added at the time of ripening the emulsion exhibited effects as a stabilizer.

EXAMPLE 3 To 1 Kg of a high speed silver iodobromide emulsion for negatives 20 ml. of a 1 percent aqueous solution of 6-methyl-7-hydroxy-2,3,4,7a-tetrazaindene was added, and the emulsion was ripened until fog formation was minimized. The emulsion was admixed with each of a red-sensitizing dye and a cyan-forming diffusionresistant coupler, a green-sensitizing dye and a magentaforrning diffusion-resistant coupler, and a bluesensitizing dye and a yellow-forming diffusion-resistant coupler, respectively to form three kinds of emulsion.

Separately, 2 g of the compound (d) mentioned above was added as a cationic polymer to 1 liter of a 5 percent aqueous solution of gelatin, and the mixture was well mixed with 0.5 g of the compound (I) mentioned above as an anionic development inhibitor.

I thereby to prepare a coating solution for an interlayer,

lution for the substratum layer with black colloidal silver (the amount of the colloid silver was adjusted so .that the optical density of the material after coating and drying was at least 0.6) was coated on a triacetate base, and then on top of it, a red-sensitizing cyan-forming emulsion layer, an interlayer, a green-sensitizing magenta-forming emulsion layer, an interlayer (by addition of yellow colloidal silver to the above prepared solution, this layer concurrently acted as a yellow filter layer), a blue-sensitizing yellow-forming emulsion layer and an over layer were coated in this order from botto reversal development using a color forming (second) developer solution of the following formulation, followed by rinsing, bleaching and fixation to form a transparent color positive image. The development inhibitor added to the interlayer, over layer and substratum layer acted effectively in the first development, and the sensitivity and gradation of the three layers could be easily balanced. This has nothing to do with the color fog of the final image. In the second (color forming) development, the silver halide grains remaining undeveloped in the first development were completely developed to convert them to a color image. There isno particular need for using a development inhibitor or for controlling the balance of gradation. The color fog of the final color positive image occurs only when silver halide grains present in the highlight part in the first development still remain undeveloped. An organic development inhibitor is not particularly required, but an inorganic inhibitor such as potassium bromide or hydroxylamine is generally needed and Formulation of the black-and-white (first) developer solution Sodium'acetate (crystals) Potash alum Potassium metabisulfite Sodium hydrogensulfate Formulation of the color forming (second) developer solution wwur immune:

Sodium sulfite (anhydride) Sodium carbonate monohydrate 7 Sulfuric acid hydroxylamine Potassium bromide N-ethyI-N-hydroxycthyl-paraamino aniline sulfate Water to make The colloidal silver in the antihalation layer or yellow filter layer was removed by a bleaching bath and became colorless, same as in the preparation of general commercially available photographic materials.

While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.

What is claimed is:

1. A multilayer silver halide photographic material for use in color photography comprising silver halide photographic emulsion layers and auxiliary layers containing no silver halide emulsion, both layers being coated in a superposed relationship; wherein either the emulsion layers or the auxiliary layers contain an anionic development inhibitor in the form of a complex mwithasati nis 2912mm- 2. The photographic material of claim 1 wherein said anionic development inhibitor is selected from the group consisting of sodium benzotriazole-S-sulfonate, sodium benzimidazole-S-sulfonate, sodium 2-methylbenzimidazole-S-sulfinate, thiazolidine-4-carboxylic acid, 2-phenyl-thiazolidine-4-carboxylic acid, l,5-di(osulfophenyl)-s-tria2olidine-( l,2-a)-s-triazolidine-3,7-

dithione, sodium salt of 2-mercapto-6- sulfobenzimidazole, sodium 2-mercapto-3-ethylbenzimidazole-6-sulfonate, sodium salt of 2-mercapto- S-sulfobenzothiazole, Z-mercapto-benzoxazole-5- carboxylic acid, sodium 2-mercapto-5-chlorobenzoxazole-7-sulfonate, sodium Z-mercapto-l, 8'-naphthoxazole-6'-sulfonate, l-(m-sulfophenyl)-5- mercapto-tetrazole and 2-mercapto-4-(pgarberrahsnrl):li3A- h di wleirt i aea,

trimethyl ammonium chloride, polyvinyl-benzyltriethyl ammonium chloride, polyvinyl benzylmorpholium methyl chloride, polyvinyl benzylcyclohexyl ammonium chloride, polyvinyl benzylpicolinium chloride,poly-4-vinyl benzyl-triethanol ammonium chloride, methyl chloride salt of a me- 'thylamino-diethanol monoester of polymethacrylic acid, benzyl chloride salt of a dimethylaminoethanol ester of polymethacrylic acid, N,N-dimethyl-3,5- methylene-piperidinium chloride resin, partially aminoguanido-modified product (acetate) of polyvinyl methyl ketone, partially aminoguanido-modified product (acetate) of a partial 2-keto butyraldehyde acetal of polyvinyl alcohol and partially aminoguanidornodified dialdehyde starch.

Claims (3)

1. 2. The photographic material of claim 1 wherein said anionic development inhibitor is selected from the group consisting of sodium benzotriazole-5-sulfonate, sodium benzimidazole-5-sulfonate, sodium 2-methyl-benzimidazole-5-sulfinate, thiazolidine-4-carboxylic acid, 2-phenyl-thiazolidine-4-carboxylic acid, 1,5-di(o-sulfophenyl)-s-triazolidine-(1,2-a)-s-triazolidine-3,7-dithione, sodium salt of 2-mercapto-6-sulfobenzimidazole, sodium 2-mercapto-3-ethyl-benzimidazole-6-sulfonate, sodium salt of 2-mercapto-5-sulfobenzothiazole, 2-mercapto-benzoxazole-5-carboxylic acid, sodium 2-mercapto-5-chloro-benzoxazole-7-sulfonate, sodium 2-mercapto-1'', 8''-naphthoxazole-6''-sulfonate, 1-(m-sulfophenyl)-5-mercapto-tetrazole and 2-mercapto-4-(p-carboxyphenyl)-1,3,4-thiodiazole-5-thione.
2. 3. The photographic material of claim 1 wherein said cationic polymer is a synthetic vinyl polymer or a modified natural polymer.
3. 4. The photographic material of claim 3 wherein said cationic polymer is selected from the group consisting of poly-2-vinyl pyridine, poly-4-vinyl pyridinium methyl paratoluene-sulfonic acid salt, polyvinyl benzyl-trimethyl ammonium chloride, polyvinyl-benzyl-triethyl ammonium chloride, polyVinyl benzyl-morpholium methyl chloride, polyvinyl benzyl-cyclohexyl ammonium chloride, polyvinyl benzyl-picolinium chloride,poly-4-vinyl benzyl-triethanol ammonium chloride, methyl chloride salt of a methylamino-diethanol monoester of polymethacrylic acid, benzyl chloride salt of a dimethylaminoethanol ester of polymethacrylic acid, N,N-dimethyl-3,5-methylene-piperidinium chloride resin, partially aminoguanido-modified product (acetate) of polyvinyl methyl ketone, partially aminoguanido-modified product (acetate) of a partial 2-keto butyraldehyde acetal of polyvinyl alcohol and partially aminoguanido-modified dialdehyde starch.

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