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(11) | EP 0 373 382 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Silver halide color photosensitive material |
| (57) A silver halide color photosensitive material includes a support, on which at least
one a blue-sensitive silver halide emulsion layer, a high-speed red-sensitive silver
halide emulsion layer, a high-speed green-sensitive silver halide emulsion layer,
at least one low-speed green-sensitive silver halide emulsion layer, and at least
one low-speed red-sensitive silver halide emulsion layer are sequentially arranged
from the farthest side from the support in the order named. A non-photosensitive layer
may be interposed between adjacent color-sensitive emulsion layers if necessary.
A yellow filter layer can be arranged between the blue-sensitive silver halide emulsion
layer and the high-speed red-sensitive silver halide emulsion layer. |
[0001] The present invention relates to a high-speed photographic color photosensitive material and, more particularly, to a photographic color photosensitive material which can be rapidly processed and has good storage stability.
[0002] Recently, as techniques of photographic photosensitive materials have been developed, many high-speed photosensitive materials have become available. To provide a variety of applications in the art of photography using the high-speed photosensitive materials, such as photography performed in a dark room without using a stroboscope, photography performed by using a zoom lens with a high-speed shutter such as a sports photograph, and photography requiring long-time exposure such as an astronomical photograph is an everlasting theme of this field of art.
[0003] Many efforts have been made to increase the sensitivity of a photosensitive material. Many studies have been made concerning the shape of a silver halide grain, a method of preparing a composition or the like, chemical sensitization, spectral sensitization, additives, a coupler structure, and the like, and several useful inventions have been made. Since, however, demands for a high-speed photosensitive material overwhelm technical developments, these inventions are not yet satisfactory. Therefore, in the field of art, a high-speed photosensitive material is normally manufactured by using a method of increasing the size of a silver halide emulsion grain in combination with the other technique, in order to increase the sensitivity.
[0004] When the size of a silver halide emulsion grain is increased, the sensitivity can be increased to some extent. As long as the content of a silver halide is maintained constant, however, the number of silver halide emulsion grains is inevitably decreased. Therefore, the number of development start points is decreased, and the graininess is significantly degraded. Known measures to eliminate this drawback include: a photosensitive material having two or more emulsion layers having the same color sensitivity and different sensitivities, i.e., different silver halide grain sizes as described in British Patent 923,045 and JP-B-49-15495 ("JP-B" means examined Japanese patent application); use of a high-speed reactive coupler as described in, e.g., JP-A-55-62454 ("JP-A" means unexamined published Japanese patent application); use of a so-called DIR coupler or DIR compound as described in, e.g., U.S. Patents 3,227,554 and 3,632,435; use of a coupler capable of releasing a mobile dye as described in British Patent 2,083,640; and use of a silver halide having a high average silver iodide content as described in JP-A-60-128443.
[0005] Although these methods are inventions having significant effects, respectively, they are not satisfactory techniques to meet a great demand for high sensitivity and high image quality. Therefore, in order to increase the grain size of a silver halide emulsion grain and, at the same time, the number of development start points, a high-speed color negative photosensitive material has been designed to have a maximum silver halide emulsion grain content as long as various photographic properties such as a desilverizing property during bleach-fixing can be maintained good.
[0006] In order to increase the sensitivity of a color photosensitive material or to increase both the sensitivity and image quality of such a color photosensitive material, an arrangement of layers in a multilayered color photosensitive material is changed in conventional techniques. For example, U.S. Patents 4,157,917 and 4,165,236 disclose techniques in which a part of red- or green-sensitive layers is arranged outside (viewed from a support side) of a yellow filter layer so as to increase the image quality. In addition, U.S. Patent 4,184,876 discloses a technique in which high-speed green- and red-sensitive layers are combined into a single high-speed unit, low-speed green- and red-sensitive layers are combined into a single low-sensitive unit, and the high-speed unit is located outside the low-speed unit, thereby increasing the sensitivity. Since, however, these techniques are unsatisfactory although they have partially achieved the above object, many other patent applications have been applied, in which improved techniques are disclosed. For example, West German Patent 3,410,639 discloses a technique in which a high-speed portion in a blue-sensitive layer is incorporated in a high-speed unit; and West German Patent 3,411,966, EP 155814, EP 124861, JP-A-59-177552 and JP-A-59-180556 disclose techniques in which a high-speed unit comprising blue-, green-, and red-sensitive layers is combined with another technique.
[0007] In addition, U.S. Patent 4,129,446 describes a positional relationship between a high-speed unit and a yellow filter, U.S. Patent 4,186,016 describes a connection relationship between high- and low-speed units, U.S. Patent 4,267,264 describes a relationship between a green-sensitive layer and a high-speed red-sensitive layer, and British Patent 1,560,965 and U.S. Patent 4,186,011 define an interlayer.
[0008] None of the above techniques concerning a layer arrangement and the techniques for improving them, however, can provide satisfactory properties although they have partially achieved the object. In particular, these techniques are unsatisfactory in image quality such as a color reproduction property and tend to subject to degradation of the image quality because a coated silver amount is larger than that in a conventional layer arrangement and therefore a photosensitive material is adversely affected by radiation during storage.
[0009] It is a first object of the present invention to provide a color photosensitive material with high image quality and sensitivity.
[0010] It is a second object of the present invention to provide a color photosensitive material with high image quality and sensitivity which can be processed at high speed.
[0011] It is a third object of the present invention to provide a high-speed color photosensitive material in which degradation in properties such as an increase in fogging density occurring during storage after the manufacture is minimized.
[0012] According to the present invention, these objects and other objects which will become apparent in the following description have been achieved by a silver halide color photosensitive material comprising:
a support; and
a layer arrangement which is supported on the support and includes at least one blue-sensitive silver halide emulsion layer, a high-speed red-sensitive silver halide emulsion layer, a high-speed green-sensitive silver halide emulsion layer, at least one low-speed green-sensitive silver halide emulsion layer, and at least one low-speed red-sensitive silver halide emulsion layer sequentially arranged adjacent to each other, from the farthest side from the support, in the order named, optionally with a non-photosensitive layer being interposed between the adjacent color-sensitive emulsion layers. The layer arrangement may include a yellow filter layer between the blue-sensitive silver halide emulsion layer and the high speed red-sensitive silver halide emulsion layer.
[0013] A photosensitive material of the present invention comprises a color photosensitive material coated on a support. In this photosensitive material, five essential color-sensitive emulsion layers, i.e., at least one blue-sensitive silver halide emulsion layer, a high-speed red-sensitive silver halide emulsion layer, a high-speed green-sensitive silver halide emulsion layer, at least one low-speed green-sensitive silver halide emulsion layer, and at least one low-speed red-sensitive silver halide emulsion layer are coated in the layer arrangement as defined above. A yellow filter layer may be provided between the blue-sensitive silver halide emulsion layer and the high-speed red-sensitive silver halide emulsion layer, or no yellow filter layer is provided.
[0014] In the present invention, the above layer arrangement includes at least one blue-sensitive silver halide emulsion layer (to be also referred to as a "blue-sensitive emulsion layer" hereinafter) located farthest from the support of the five essential color-sensitive layers. Preferably, the layer arrangement includes two or three blue-sensitive emulsion layers having substantially the same color sensitivity. In this case, layers having "substantially the same color sensitivity" are those having maximum sensitivities falling within the range of 400 to 500 nm and having the same or approximate spectral sensitivity distributions. When a plurality of blue-sensitive emulsion layers are to be formed, a layer having higher sensitivity is preferably arranged farther from a support.
[0015] The term "high-speed" or "low-speed" used for the red-sensitive silver halide emulsion layer (to be also referred to as a "red-sensitive emulsion layer" hereinafter) and the green-sensitive silver halide emulsion layer (to be also referred to as a "green-sensitive emulsion layer" hereinafter) is a relative concept. A toe speed difference between these emulsion layers having relatively high and low speeds is preferably 0.1 to 1.0, and more preferably, 0.2 to 0.7 in common logarithm expression of an exposure amount. In addition, a high- or low-speed red- or green-emulsion layer may consist of two layers having different sensitivities or speeds, as will be described later. In this case, the preferable value of a relative speed difference is the same as described above.
[0016] Two, high- and low-speed or three, high-, medium-, and low-speed red- or green-speed emulsion layers have substantially the same color sensitivity. In this case, red- or green-sensitive emulsion layers having "substantially the same color sensitivity" are those having maximum sensitivities falling within the range of 600 to 700 nm or 500 to 600 nm, respectively, and the similar spectral sensitivity distributions.
[0017] In the present invention, each of the blue-, green-, and red-sensitive emulsion layer preferably contains at least one yellow, magenta, and cyan coupler, respectively.
[0018] The present invention is preferably formulated into a negative color photosensitive material. In this case, preferably, a transparent flexible support is used as the support for the layer arrangement and the material has a specified photographic sensitivity of 320 to 6400 (to be described later). The sensitivity can be obtained by the techniques well known in the art, including selection of grain sizes.
[0019] Examples of an arrangement order of layers in the color photosensitive material of the present invention will be described below, in which the layers are arranged on the support in the order mentioned from the closest side of the support. The present invention, however, is not limited to these examples.
(1) a support, a low-speed red-sensitive emulsion layer (RL), a medium-speed red-sensitive emulsion layer (RM), an interlayer (IL), a low-speed green-sensitive emulsion layer (GL), a medium-speed green-sensitive emulsion layer (GM), a high-speed green-sensitive emulsion layer (GH), an interlayer (IL), a high-speed red-sensitive emulsion layer (RH), a yellow filter layer (YF), a low-speed blue-sensitive emulsion layer (BL), a medium-speed blue-sensitive emulsion layer (BM), a high-speed blue-sensitive emulsion layer (BH), and a protective layer (PL)
(2) a support, RL, RM, IL, GL, GM, IL, GH, IL, RH, YF, BL, BM, BH, and PL
(3) a support, RL, RM, IL, GL, GM, IL, GH, IL, RH, IL, BL, BM, BH, and PL
[0020] The yellow filter layer is a layer of a yellow-colored non-photosensitive material and contains yellow colloidal silver or yellow dye. Preferably, the yellow filter layer is decolored after development.
[0021] In each of the layer arrangement (1) to (3), each of emulsion layers having different color sensitivities is constituted by L, M, and H layers having different speed sensitivities. Each emulsion layer, however, may be constituted by only L and H layers. The blue-sensitive layer may be constituted by only one layer. A layer (Ref) which reflects light may be formed immediately below a high-speed layer to obtain a structure in which BL, BM, Ref, and BH are arranged in this order from the support. In order to accelerate development of a high-speed layer, a non-photosensitive fine grain emulsion layer may be formed as a nonphotosensitive interlayer adjacent to the high-speed layers. In each of the layer arrangements (1) to (3), a medium-speed layer is arranged adjacent to a low-speed layer. A medium-speed layer, however, may be arranged adjacent to a high-speed layer. An interlayer (e.g., IL in an arrangement of GL, GM, IL, and GH of the arrangement (2)) intervening emulsion layers of the same color sensitivity may contain a compound (so-called scavenger) for trapping an oxide of a developing agent. In addition, an emulsion may be added to an interlayer. The protective layer PL need not be a single layer but may consist of two or more layers. In this case, the outermost layer preferably contains a mat agent. When the protective layer contains oil drops in order to adjust film physical properties, it is preferably constituted by two or more layers. In this case, the outermost layer has a smaller oil/binder (weight) ratio than that of the adjacent inside layer. An antihalation layer and, if necessary, an interlayer formed on the antihalation layer are normally formed between the low-speed red-sensitive emulsion layer and the support. The protective layer or various interlayers described above may contain couplers and DIR compounds as described in JP-A-61-43748, JP-A-59-113438, JP-A-59-113440, JP-A-61-20037, and JP-A-61-20038.
[0022] The color photosensitive material of the present invention has blue-, green-, and red-sensitive silver halide emulsion layers. Of these layers, at least each of the green- and red-sensitive layers is constituted by two or more layers having different sensitivities. In order to improve graininess of the green- or red-sensitive layer and, if necessary, that of the blue-sensitive layer, an arrangement in which each color-sensitive layer is constituted by three layers is most preferably. This technique is different from a three-layered arrangement of color-sensitive emulsion layers having the same sensitivity described in JP-B-49-15495 because a particularly good effect is obtained by the technique in combination with the layer arrangement in a reversed order in accordance with the present invention.
[0023] A non-photosensitive layer may be formed between the photosensitive emulsion layers. This non-photosensitive layer may be interposed between two or more emulsion layers having the same color sensitivity. When photosensitive emulsion layers having different color sensitivities are formed adjacent to each other, a non-photosensitive layer is preferably formed between such layers. Such a non-photosensitive interlayer may contain a scavenger substance for a color developing agent oxide. It is also preferable to form a non-photosensitive reflecting layer below a photosensitive emulsion layer to improve the sensitivity as described in JP-A-59-160135. Although this is not always necessary, the color photosensitive material of the present invention normally contains a yellow filter layer. This yellow filter layer mainly serves to shield unnecessary blue sensitivity of the red- or green-sensitive emulsion layer and is normally formed between the high-sensitive red-sensitive silver halide emulsion layer and a blue-sensitive silver halide layer closest to the support. Effective sensitivity, however, can be improved without degrading the color reproducibility by forming the yellow filter layer at a side adjacent to the high-speed red-sensitive silver halide emulsion layer and close to the support. In this case, a tabular grain in which color sensitization sensitivity (minus blue sensitivity) is relatively higher than specific sensitivity (blue sensitivity) is preferably used in the high-speed red-sensitive emulsion layer RH.
[0024] The photosensitive material of the present invention preferably has a specified photographic sensitivity of 320 or more and a total amount of silver contained in the photosensitive material of 3.0 to 13.0 g/m². If the specified photographic sensitivity is less than 320, the layer arrangement according to the present invention need not be adopted. If the total silver amount is more than 13 g/m², it is difficult to reduce a desilverizing time since bleaching requires a long time.
[0025] The specified photographic sensitivity is a photographic sensitivity obtained by a method according to JIS K 7614-1981 for measuring an ISO sensitivity. That is, the specified photographic sensitivity is obtained by exposing a photosensitive material for sensitometry and developing the exposed material one hour, not five days defined by JIS, after exposure by a negative processing prescription CN-16 available from Fuji Photo Film Co., Ltd. The number of storage days defined in the JIS test method is reduced in order to quickly obtain a result. Since it is defined that development is performed by a method designated by each company, a storage time is specified as one hour. Therefore, this photographic sensitivity is called herein as the specified photographic sensitivity.
[0026] Note that a test method of measuring the specified photographic sensitivity is described in detail in JP-A-63-226650 (Japanese Patent Application No. 62-159115 which claimed domestic priority based on Japanese Patent Application No. 61-201756), from the upper left column on page (4) (page 440) to the upper right column on page (6) (page 442).
[0027] Several known methods can be used to analyze the silver content in the photosensitive material. For example, elemental analysis using fluorescent X-rays can be easily performed.
[0028] If the specified photographic sensitivity of the color photosensitive material of the present invention is lower than 320, an effect of a combination of an improvement in an arrangement order of layers of the multilayered color negative photosensitive material of the present invention and a silver content is not significantly achieved. The specified photographic sensitivity is preferably 400 or more, and more preferably, 800 or more.
[0029] In the photographic emulsion layers of the silver halide photographic photosensitive material of the present invention, any of silver bromide, silver iodobromide, silver iodochlorobromide, silver chlorobromide, and silver chloride can be used as a silver halide. A preferable silver halide is silver iodobromide containing 30 mol% or less of silver iodide. A most preferable silver halide is silver iodobromide containing 2 to 20 mol% of silver iodide. In order to obtain both the high sensitivity and image quality, an average silver iodide content of a silver halide in all the emulsion layers is preferably set to 8 mol% or more as described in JP-A-60-128443. It is known that when the average silver iodide content of a silver halide is increased, the graininess is significantly improved. If, however, the silver iodide content exceeds a certain level, a development speed is decreased, or a desilverizing or fixing speed is decreased. In the present invention, however, these drawbacks hardly occur even if the silver iodide content is increased, resulting in a great advantage.
[0030] A silver halide grain for use in the photographic emulsion layers of the silver halide photographic photosensitive material of the present invention preferably has a double structure constituted by a core which consists essentially of silver iodobromide containing 5 mol% or more of silver iodide and a shell which covers the core and consists essentially of silver iodobromide or silver bromide having a lower silver iodide content than that of the core. The silver iodide content of the core is more preferably 10 mol% or more, and most preferably, 20 to 44 mol%. The silver iodide content of the shell is preferably 5 mol% or less.
[0031] The core may uniformly contain silver iodide or may have a multi-phase structure consisting of silver iodobromide phases having different silver iodide contents. In the latter case, a silver iodide content of a phase having the highest silver iodide content is 5 mol% or more, and preferably, 10 mol% or more. At the same time, a silver iodide content of the shell is lower than that of a phase having the highest silver iodide content. The expression "consists essentially of silver iodobromide" means that the core or shell mainly consists of silver iodobromide but can contain up to about 1 mol% of another component (e.g., silver chloride).
[0032] A more preferable silver halide grain for use in the photographic emulsion layers of the silver halide photographic photosensitive material of the present invention has a structure in which when a diffraction intensity-vs-diffraction angle curve of a (220) face of a silver halide is obtained within a diffraction angle (2ϑ) range of 38° to 42° by using a Kß line of Cu, two diffraction maximum peaks appear corresponding to core and shell portions, with one diffraction minimum peak appearing therebetween, and the diffraction intensity corresponding to the core portion becomes 1/10 to 3/1 that of the shell portion. Most preferably, the diffraction intensity ratio is 1/5 to 3/1 or 1/3 to 3/1.
[0033] With such a double structure, a silver iodobromide emulsion having a high iodide content can be used without decreasing the development speed. Therefore, a photosensitive material having excellent graininess can be achieved with a small coating silver amount.
[0034] Although an average grain size (which is a grain diameter if a grain is spherical or almost spherical and is an edge length if a grain is cubic, and is represented by an average value based on a projected surface area) of silver halide grains in the photographic emulsion is not particularly limited, it is preferably 0.05 to 10 µm. An average size of silver halide grains in an emulsion layer having the highest sensitivity is preferably 0.5 to 4 µm, and more preferably, 0.6 to 2.5 µm.
[0036] The silver halide grain in the photographic emulsion may be a regular crystal such as a cubic or octahedral crystal, may be an irregular crystal such as a spherical or tabular crystal, or may be a combination of these crystals. Alternatively, a mixture of grains having various crystal forms may be used.
[0037] It is preferred to use a tabular grain having an aspect ratio of 5 or more because a color sensitization efficiency obtained by a sensitizing dye is increased.
[0038] Such a tabular grain can be easily prepared by methods described in, e.g., Gutoff, "Photographic Science and Engineering", Vol. 14, PP. 248 to 257, (1970); and U.S. Patents 4,434,226, 4,414,310, 4,433,048, and 4,439,520 and British Patent 2,112,157.
[0039] The photographic emulsion for use in the present invention can be prepared by using methods described in, e.g., P. Glafkides, "Chimie et Physique Photographique", Paul Montel, 1967; G.F. Duffin, "Photographic Emulsion Chemistry", The Focal Press, 1966; and V.L. Zelikman et al., "Making and Coating Photographic Emulsion", The Focal Press, 1964. That is, the photographic emulsion can be prepared by, e.g., an acid method, a neutralization method, and an ammonia method. As a system for reacting a soluble silver salt and a soluble halide, a single mixing method, a double mixing method, or a combination thereof can be used.
[0040] A so-called back mixing method for forming silver halide grains in the presence of excessive silver ions can be used. As one system of the double mixing method, a so-called controlled double jet method wherein a pAg of a liquid phase in which a silver halide is formed is kept at a constant value can be used. According to this method, a silver halide emulsion having a regular crystal form and almost uniform grain sizes is obtained.
[0041] Two types or more of independently prepared silver halide emulsions may be mixed and used in a single emulsion layer.
[0042] As a silver halide for use in the present invention, a silver halide grain having a crystal face defined by Miller indices (nnl) (n ≧ 2, n is a natural number) on its outer surface as described in Journal of Technical Disclosure No. 86-9598 is preferably used.
[0043] A silver halide grain having an internal hollow communication portion from its surface as described in JP-A-61-75337 is also preferably used. Such a silver halide grain having a large specific surface area can be effectively used in combination with the present invention because the sensitivity is increased higher than that obtained by a solid silver halide grain of the same volume upon color sensitization.
[0044] In addition, a composite grain of a combination of a host grain and a silver salt having a different composition epitaxially grown on the host grain as disclosed in JP-A-57-133540, JP-A-58-108526, or JP-A-59-162540 may be preferably used. Such a grain is preferably used in combination with the present invention since it exhibits high-speed, high-contrast photographic property.
[0045] A silver halide emulsion grown in the presence of tetrazaindene as described in JP-A-61-14630 and JP-A-60-122935 has a high silver iodide content and good monodispersion properties and therefore exhibits high sensitivity and excellent graininess. Therefore, this silver halide emulsion can be preferably used in the present invention.
[0046] A silver halide emulsion subjected to a gold-plus-sulfur sensitization or gold-plus-selenium sensitization in the presence of a nitrogen-containing heterocyclic compound as disclosed in JP-A-58-126526 has a low fogging density and high sensitivity. Therefore, this silver halide emulsion can be preferably used in the present invention.
[0047] A slightly rounded cubic or tetradecahedral crystal described in JP-A-59-149345 or JP-A-59-149344 is preferable as a silver halide emulsion for use in the present invention since a high sensitivity can be obtained.
[0048] In a process of formation or physical ripening of silver halide grains, a cadmium salt, a zinc salt, a lead salt, a thallium salt, an iridium salt or an iridium complex salt, a rhodium salt or a rhodium complex salt, or an iron salt or an iron complex salt may be used.
[0049] A silver halide emulsion whose grains are formed in the presence of iridium has high sensitivity (JP-B-43-4935 or JP-B-45-32738) and therefore is most preferably used in the present invention.
[0050] After precipitation formation or physical ripening is performed, soluble salts are normally removed from an emulsion. In this case, a conventional Nudel washing method in which gelatin is gelled can be used. Alternatively, a sedimentation method (flocculation) utilizing an inorganic salt consisting of a multivalent anion such as sodium sulfate, an anionic surfactant, an anionic polymer (e.g., polystyrenesulfonic acid) or a gelatin derivative (e.g., an aliphatic acylated gelatin, aromatic acylated gelatin, or aromatic carbamoylated gelatin) can be performed.
[0051] A silver halide emulsion is normally subjected to chemical sensitization. In order to perform chemical sensitization, a method described in H. Frieser ed., "Die Grundlagen der Photographischen Prozesse mit Silber-Halogeniden" (Akademische Verlagsgesellschaft, 1968) PP. 675 to 734 can be used.
[0052] That is, a sulfur sensitization method using active gelatin or a compound containing sulfur which can react with silver (e.g., thiosulfates, thioureas, mercapto compounds, and rhodanines); a reduction sensitization method using a reducing substance (e.g., stannous salt, amines, a hydrazine derivative, formamidinesulfinic acid, a silane compound); and a noble metal sensitization method using a noble metal compound (e.g., a gold complex salt or a complex salt of Group VIII metals of the periodic table such as Pt, Ir, and Pd) can be used singly or in a combination of two or more thereof.
[0053] In addition, a selenium sensitization method using a compound containing selenium which can react with active gelatin or silver can be preferably used in combination with another sensitization method because a high-speed emulsion can be obtained. This technique is described in, e.g., U.S. Patents 1,574,944, 1,602,592, and 1,623,499, JP-B-52-38408, JP-B-57-22090, JP-A-59-180536, U.S. Patent 4,565,778, JP-A-59-185329 and JP-A-60-150046.
[0054] The photographic emulsion for use in the present invention can be spectrally sensitized with, e.g., methine dyes. Examples of the dye include a cyanine dye, merocyanine dye, a composite cyanine dye, a composite merocyanine dye, a holopolar cyanine dye, a hemicyanine dye, a styryl dye, and hemioxonol dye. Most effective dyes are those belonging to a cyanine dye, a merocyanine dye, and a composite merocyanine dye. These dyes can contain any nucleus normally contained as a basic heterocyclic nucleus in cyanine dyes. Examples of the nucleus include pyrroline nucleus, an oxazoline nucleus, a thiazoline nucleus, a pyrrole nucleus, an oxazole nucleus, a thiazole nucleus, a selenazole nucleus, an imidazole nucleus, a tetrazole nucleus, and a pyridine nucleus; a nucleus having an alicyclic hydrocarbon ring fused to each of the above nuclei; and a nucleus having an aromatic hydrocarbon ring fused to each of the above nuclei, e.g., an indolenine nucleus, a benzindolenine nucleus, an indole nucleus, a benzoxadole nucleus, a naphthooxazole nucleus, a benzothiazole nucleus, a naphthothiazole nucleus, a benzoselenazole nucleus, a benzimidazole nucleus, and a quinoline nucleus. These nuclei may have a substituent group on its carbon atom.
[0055] A merocyanine dye or composite merocyanine dye can contain, as a nucleus having a ketomethylene structure, a 5- or 6-membered heterocyclic nucleus, e.g., a pyrazoline-5-one nucleus, a thiohydantoin nucleus, a 2-thioxazolidine-2,4-dione nucleus, a thiazolidine-2,4-dione nucleus, a rhodanine nucleus, and a thiobarbituric acid nucleus.
[0056] Examples of an effective sensitizing dye are described in, e.g., West German Patent 929,080, U.S. Patents 2,231,658, 2,493,748, 2,503,776 2,519.001. 2,912,329, 3,656,959, 3,672,897, 3,694,217, 4,025,349, and 4,046,572, British Patent 1,242,588, and JP-B-44-14030 and JP-B-52-24844.
[0057] These sensitizing dyes can be used singly or in a combination of two or more thereof. A combination of the sensitizing dyes is often used especially in order to perform supersensitization. Typical examples of the combination are described in U.S. Patents 2,688,545, 2,977,229, 3,397,060, 3,522,052, 3,527,641, 3,617,293, 3,628,964, 3,666,480, 3,672,898, 3,679,428, 3,703,377, 3,769,301, 3,814,609, 3,837,862, and 4,026,707, British Patents 1,344,281 and 1,507,803, JP-B-43-4936 and JP-B-53-12375, and JP-A-52-110618 and JP-A-52-109925.
[0058] The emulsion may contain, in addition to the sensitizing dye, a dye not having a spectral sensitizing effect or a substance substantially not absorbing visible light and having supersensitization. For example, the emulsion may contain aminostyl compounds substituted with a nitrogen-containing heterocyclic group (described in, e.g., U.S. Patents 2,933,390 and 3,635,721), an aromatic organic acid formaldehyde condensate (described in, e.g., U.S. Patent 3,743,510), cadmium salt, and an azaindene compound. Combinations described in U.S. Patents 3,615,613, 3,615,641, 3,617,295, and 3,635,721 are most effective.
[0059] Photographic additives for use in this invention are described in Research Disclosures (RD), Nos. 17643 and 18716 and they are summarized in the following table.
| Additives | RD No.17643 | RD No.18716 | |
| 1. | Chemical sensitizers | page 23 | page 648, right column |
| 2. | Sensitivity increasing agents | do. | |
| 3. | Spectral sensitizers, supersensitizers | pages 23-24 | page 648, right column to page 649, right column |
| 4. | Brighteners | page 24 | |
| 5. | Antifoggants and stabilizers | pages 24-25 | page 649, right column |
| pages 24-25 | |||
| 6. | Light absorbent, filter dye, ultraviolet absorbents | pages 25-26 | page 649, right column to page 650, left column |
| 7. | Stain preventing agents | page 25, right column | page 650, left to right columns |
| 8. | Dye image stabilizer | page 25 | |
| 9. | Hardening agents | page 26 | page 651, left column |
| 10. | Binder | page 26 | do. |
| 11. | Plasticizers, lubricants | page 27 | page 650, right column |
| 12. | Coating aids, surface active agents | pages 26-27 | do. |
| 13. | Antistatic agents | page 27 | do. |
[0060] In order to prevent degradation in photographic properties caused by formaldehyde gas, a compound capable of reacting with and setting formaldehyde described in U.S. Patent 4,411,987 or 4,435,503 is preferably added to the photosensitive material.
[0061] Various color couplers can be used in the present invention. Specific examples of these couplers are described in above-described RD, No. 17643, VII-C to VII-G as patent references.
[0062] Preferred examples of a yellow coupler are described in, e.g., U.S. Patents 3,933,501, 4,022,620, 4,326,024, 4,401,752, and 4,248,961, JP-B-58-10739, British Patents 1,425,020 and 1,476,760, U.S. Patents 3,973,968, 4,314,023, and 4,511,649, and EP 249,473A.
[0063] Examples of a magenta coupler are preferably 5-pyrazolone and pyrazoloazole compounds, and more preferably, compounds described in, e.g., U.S. Patents 4,310,619 and 4,351,897, EP 73,636, U.S. Patents 3,061,432 and 3,725,067, RD No. 24220 (June 1984) JP-A-60-33552, RD No. 24230 (June 1984), JP-A-60-43659, JP-A-61-72238, JP-A-60-35730, JP-A-55-118034, and JP-A-60-185951, and U.S. Patents 4,500,630, 4,540,654, and 4,556,630.
[0064] Examples of a cyan coupler are phenol and naphthol couplers, and preferably, those described in, e.g., U.S. Patents 4,052,212, 4,146,396, 4,228,233, 4,296,200, 2,369,929, 2,801,171, 2,772,162, 2,895,826, 3,772,002, 3,758,308, 4,334,011, and 4,327,173, West German Patent Application (OLS) No. 3,329,729, EP 121,365A and 249,453A, U.S. Patents 3,446,622, 4,333,999, 4,451,559, 4,427,767, 4,690,889, 4,254,212, and 4,296,199, and JP-A-61-42658.
[0065] Preferable examples of a colored coupler for correcting additional, undesirable absorption of a colored dye are those described in RD No. 17643, VII-G, U.S. Patent 4,163,670, JP-B-57-39413, U.S. Patents 4,004,929 and 4,138,258, and British Patent 1,146,368.
[0066] Preferable examples of a coupler capable of forming colored dyes having proper diffusibility are those described in U.S. Patent 4,366,237, British Patent 2,125,570, EP 96,570, and West German Patent Application (OLS) No. 3,234,533.
[0067] Typical examples of a polymerized dye-forming coupler are described in U.S. Patents 3,451,820, 4,080,211, 4,367,282, 4,409,320, and 4,576,910, and British Patent 2,102,173.
[0068] Couplers releasing a photographically useful residue upon coupling are preferably used in the present invention. DIR couplers, i.e., couplers releasing a development inhibitor are described in the patents cited in the above-described RD No. 17643, VII-F, JP-A-57-151944, JP-A-57-154234, JP-A-60-184248, and JP-A-63-37346, and U.S. Patent 4,248,962.
[0069] Preferable examples of a coupler imagewise releasing a nucleating agent or a development accelerator upon development are those described in British Patent 2,097,140 and 2,131,188, and JP-A-59-157638 and JP-A-59-170840.
[0070] Examples of a coupler which can be used in the photosensitive material of the present invention are competing couplers described in, e.g., U.S. Patent 4,130,427; poly-equivalent couplers described in, e.g., U.S. Patents 4,283,472, 4,338,393, and 4,310,618; a DIR redox compound releasing coupler or DIR coupler releasing coupler, or a DIR coupler releasing redox compound or DIR redox compound releasing redox described in, e.g., JP-A-60-185950, JP-A-62-24252, and JP-A-62-291645; couplers releasing a dye which turns to a colored form after being released described in EP 173,302A; bleaching accelerator releasing couplers described in, e.g., RD. Nos. 11449 and 24241 and JP-A-61-201247; and a legand releasing coupler described in, e.g., U.S. Patent 4,553,477.
[0071] Examples of a color coupler usable in the present invention are listed in Table A. A usable coupler, however, is not limited to those couplers.
[0072] The couplers for use in this invention can be introduced in the photosensitive materials by various known dispersion methods.
[0073] Examples of a high-boiling solvent used in an oil-in-water dispersion method are described in, e.g., U.S. Patent 2,322,027.
[0074] Examples of a high-boiling organic solvent to be used in the oil-in-water dispersion method and having a boiling point of 175°C or more at normal pressure are phthalate esters (e.g., dibutylphthalate, dicyclohexylphthalate, di-2-ethylhexylphthalate, decylphthalate, bis(2,4-di-t-amylphenyl)phthalate, bis(2,4-di-t-amylphenyl)isophthalate, and bis(1,1-diethylpropyl)phthalate), phophate or phosphonate esters (e.g., triphenylphosphate, tricresylphosphate, 2-ethylhexyldiphenylphosphate, tricyclohexylphosphate, tri-2-ethylhexylphosphate, tridodecylphosphate, tributyoxyethylphosphate, trichloropropylphosphate, di-2-ethylhexylphenylphosphonate), benzoate esters (e.g., 2-ethylhexylbenzoate, dodecylbenzoate, and 2-ethylhexyl-p-hydroxybenzoate), amides (e.g., N,N-diethyldodecaneamide, N,N-diethyllaurylamide, and N-tetradecylpyrrolidone), alcohols or phenols (e.g., isostearylalcohol and 2,4-di-tert-amylphenol), aliphatic carboxylate esters (e.g., bis(2-ethylhexyl)sebacate, dioctylazelate, glyceroltributylate, isostearyllactate, and trioctylcitrate), an aniline derivative (e.g., N,N-dibutyl-2-butoxy-5-tert-octylaniline), and hydrocarbons (e.g., paraffin, dodecylbenzene, and diisopropylnaphthalene). An organic solvent having a boiling point of about 30°C or more, and preferably, 50°C to about 160°C can be used as a co-solvent. Typical examples of the co-solvent are ethyl acetate, butyl acetate, ethyl propionate, methylethylketone, cyclohexanone, 2-ethoxyethylacetate, and dimethylformamide.
[0075] Steps and effects of a latex dispersion method and examples of an impregnating latex are described in, e.g., U.S. Patent 4,199,363 and West German Patent Application (OLS) Nos. 2,541,274 and 2,541,230.
[0076] The present invention can be applied to various color photosensitive materials. Representative examples of the material are a color negative film for a general purpose or a movie, and a color reversal film for a slide or a television.
[0077] Examples of a support suitable for use in this invention are described in the above-mentioned RD. No. 17643, page 28 and ibid., No. 18716, page 647, right column to page 648, left column.
[0078] The color photographic photosensitive materials of this invention can be developed and processed by the ordinary processes as described, for example, in the above-described Research Disclosure, No. 17643, pages 28 to 29 and ibid., No. 18716, page 651, left to right columns.
[0079] A color developer used in developing of the photosensitive material of the present invention is an aqueous alkaline solution mainly consisting of, preferably, an aromatic primary amine-based color developing agent. As the color developing agent, although an aminophenol-based compound is effective, a p-phenylenediamine-based compound is preferably used. Typical examples of the p-phenylenediamine-based compound are 3-methyl-4-amino-N,N-diethylaniline, 3-methyl-4-amino-N-ethyl-N-ß-hydroxyethylaniline, 3-methyl-4-amino-N-ethyl-N-ß-methanesulfonamidoethylaniline, 3-methyl-4-amino-N-ethyl-N-ß-methoxyehtylaniline, and sulfates, hydrochlorides and p-toluenesulfonates thereof. These compounds can be used in a combination of two or more thereof in accordance with applications.
[0080] In general, the color developer contains a pH buffering agent such as a carbonate, a borate or a phosphate of an alkali metal, and a development restrainer or antifoggant such as a bromide, an iodide, a benzimidazole, a benzothiazole or a mercapto compound. If necessary, the color developer may also contain a preservative such as hydroxylamine, diehtylhydroxylamine, a hydrazine sulfite, a phenylsemicarbazide, triethanolamine, a catechol sulfonic acid or a triethylenediamine(1,4-diazabicyclo[2,2,2]octane); an organic solvent such as ethyleneglycol or diethyleneglycol; a development accelerator such as benzylalcohol, polyethyleneglycol, a quaternary ammonium salt or an amine; a dye forming coupler; a competing coupler; a fogging agent such as sodium boron hydride; an auxiliary developing agent such as 1-phenyl-3-pyrazolidone; a viscosity imparting agent; and a chelating agent such as an aminopolycarboxylic acid, an aminopolyphosphonic acid, an alkylphosphonic acid or a phosphonocarboxylic acid. Examples of the chelating agent are ethylenediaminetetraacetic acid, nitrilotriacetic acid, diethylenetriaminepentaacetic acid, cyclohexanediaminetetraacetic acid, hydroxyethyliminodiacetic acid, 1-hydroxyethylidene-1,1-diphosphonic acid, nitrilo-N,N,N-trimethylenephosphonic acid, ethylenediamine-N,N,N′,N′-tetramethylenephosphonic acid and ethylenediamine-di(o-hydroxyphenylacetic acid), and salts thereof.
[0081] In order to perform reversal development, black-and-white development is performed and then color development is performed. As a black-and-white developer, well-known black-and-white developing agents, e.g., a dihydroxybenzene such as hydroquinone, a 3-pyrazolidone such as 1-phenyl-3-pyrazolidone, and an aminophenol such as N-methyl-p-aminophenol can be used singly or in a combination of two or more thereof.
[0082] The pH of the color and black-and-white developers is generally 9 to 12. Although a replenishment amount of the developer depends on a color photographic photosensitive material to be processed, it is generally 3 liters or less per m² of the photosensitive material. The replenishment amount can be decreased to be 500 mℓ or less by decreasing a bromide ion concentration in a replenishing solution. In order to decrease the replenishment amount, a contact area of a processing tank with air is preferably decreased to prevent evaporation and oxidation of the solution upon contact with air. The replenishment amount can be decreased by using a means capable of suppressing an accumulation amount of bromide ions in the developer.
Example 1
[0083] A sample 101 as a multilayered color photosensitive material consisting of layers having the following compositions were formed, in the order mentioned below, on an undercoated triacetylcellulose film support.
(Compositions of Photosensitive Layers)
[0084] The coating amount of a silver halide and colloid silver are represented in units of g/m² of silver, that of additives and gelatin is represented in units of g/m², and that of sensitizing dye is represented by the number of mols per mol of the silver halide in the same layer.
[0085] Symbols representing additives have the following meanings. Note that if an additive has a plurality of effects, only one of the effects is shown.
[0086] UV; ultraviolet absorbent, Solv; high-boiling organic solvent, W; coating aid, H; hardener, ExF; dye, ExS; sensitizing dye, ExC; cyan coupler, ExM; magenta coupler, ExY; yellow coupler, Cpd; additive
[0088] As shown in Table 1 below, a sample 102 was prepared by switching the layers 9 and 11 in the sample 101, and a sample 103 was prepared by removing the layer 12 of the sample 102. A silver amount and a compound coating amount of each sample are represented by an increased/decreased amount with respect to the sample 101.
[0089] That is, "silver amount + 0.1 g" of the layer 9 in the sample 102 is based on the layer GH in the sample 101, and "silver amount - 0.5 g" of the layer 11 in the sample 102 is based on the layer RH in the sample 101. An amount of a sensitizing dye was changed in proportional to the silver amount.
Table 1
| Sample | 101 | 102 | 103 |
| Layer 7 | Medium-Speed Green-Sensitive Emulsion Layer (GM) | the same as left | the same as left |
| Layer 8 | Interlayer | Interlayer Cpd-6 -0.05g | the same as left |
| Layer 9 | Hight-Speed Red-Sensitive Emulsion Lyaer (RH) | High-Speed Green-Sensitive Emulsion Layer (GH) | the same as left |
| silver amount +0.1g | |||
| gelatin +0.2g | |||
| Layer 10 | Interlayer | the same as left | Interlayer (the same as 101) |
| Layer 11 | High-Speed Green-Sensitive Emulsion Layer (GH) | High-Speed Red-Sensitive Emulsion Layer (RH) | the same as left |
| silver amount -0.5g | |||
| gelatin -0.2g | |||
| Layer 12 | Yellow Filter Layer | the same as left | |
| Layer 13 | Interlayer | the same as left | the same as left |
| Total Silver Amount | 9.75 | 9.35 | 9.35 |
[0090] The samples 101 to 103 were imagewise exposed and then subjected to the following processing.
[0091] The color development process was performed at 38°C in accordance with the following process steps.
| Color Development | 3 min. 15 sec. |
| Bleaching | 6 min. 30 sec. |
| Washing | 2 min. 10 sec. |
| Fixing | 4 min. 20 sec. |
| Washing | 3 min. 15 sec. |
| Stabilization | 1 min. 05 sec. |
[0092] The processing solution compositions used in the respective steps were as follows.
| Color Development Solution | |
| Diethylenetriaminepentaacetic Acid | 1.0 g |
| 1-hydroxyethylidene-1,1-diphosphonic acid | 2.0 g |
| Sodium Sulfite | 4.0 g |
| Potassium Carbonate | 30.0 g |
| Potassium Bromide | 1.4 g |
| Potassium Iodide | 1.3 mg |
| Hydroxylamine Sulfate | 2.4 g |
| 4-(N-ethyl-N-β-hydroxyethylamino)-2-methylanilinesulfate | 4.5 g |
| Water to make | 1.0 ℓ |
| pH | 10.0 |
| Bleaching Solution | |
| Ferric Ammonium Ethylenediaminetetraacetate | 100.0 g |
| Disodium Ethylenediaminetetraacetate | 10.0 g |
| Ammonium Bromide | 150.0 g |
| Ammonium Nitrate | 10.0 g |
| Water to make | 1.0 ℓ |
| pH | 6.0 |
| Fixing Solution | |
| Disodium Ethylenediaminetetraacetate | 1.0 g |
| Sodium Sulfite | 4.0 g |
| Ammonium Thiosulfate Aqueous solution (70%) | 175.0 mℓ |
| Sodium Bisulfite | 4.6 g |
| Water to make | 1.0 ℓ |
| pH | 6.6 |
| Stabilizing Solution | |
| Formalin (40%) | 2.0 mℓ |
| Polyoxyethylene-p-monononylphenylether (average polymerization degree = 10) | 0.3 g |
| Water to make | 1.0 ℓ |
[0093] Densities of obtained images were measured to obtain relative sensitivities. The results are shown in Table 2. Each sensitivity is an exposure amount at a density of fogging density + 0.1 and is represented as a relative value assuming that each of the B, G, and R sensitivities of the sample 101 is 100.
Table 2
| Sample | Relative Sensitivity | ||
| B | G | R | |
| 101 (Comparative Example) | 100 | 100 | 100 |
| 102 (Present Invention) | 100 | 93 | 110 |
| 103 (Present Invention) | 105 | 98 | 117 |
[0094] Each sample was exposed through a step wedge for RMS graininess measurement to perform similar color development, and an RMS value was measured by using a 48-µm diameter aperture. As a result, measurement values of the samples 101 to 103 were 0.0293, 0.0260, and 0.0270, respectively, at R density DR = 0.6.
[0095] As is apparent from the above results, each of the samples 102 to 103 according to the present invention has higher sensitivity and better graininess of the red-sensitive layer than those of the sample 101 regardless of its small silver amount. That is, the present invention is proved to be effective.
Example 2
[0096] A sample 201 was prepared as sample 102 except that the layer 9 in the sample 102 was removed and the coating amount of layer 11 was decreased by 15%. The sample 201 was subjected to the same processing as in Example 1. As a result, although the sensitivities of the samples 102 and 201 are substantially the same, their RMS measurement values at DG = 0.6 were 0.0265 and 0.0310, respectively. That is, the graininess of the green-sensitive layer is degraded since the layer 8 was removed.
Example 3
[0097] The samples 101 to 103 of Example 1 were stored at room temperature for nine months and then subjected to the same processing as in Example 1, and measurement of the graininess was performed. As a result, measurement values of the samples 101 to 103 were 0.0363, 0.030, and 0.0320, respectively, at R density DR = 0.6. That is, the graininess of each sample of the present invention was not much degraded after storage.
Example 4
[0098] The samples 101 and 102 of Example 1 were subjected to uniform exposure of 5 CMS and then to the processing of Example 1. In this processing, a bleaching time was changed such that a remaining silver amount became 6 µg/cm2 or less by a fluorescent X-ray method. As a result, a time required for the sample 101 was four minutes and ten second, while it was three minutes and thirty seconds for the sample 102. That is, the processing time can be reduced by the sample of the present invention.
[0099] As has been described above, according to the layer arrangement of the present invention, desired photographic sensitivity can be achieved by a smaller coating silver amount than that of silver halide color photographic material according to the conventional layer arrangement (a support, RL, RM, GL, GM, RH, GH, YF, BL, BM, BH, and PL) assumed to be preferable to obtain high sensitivity. Therefore, since a desilverizing load after color development can be reduced, high-speed processing is achieved. In addition, since predetermined high sensitivity is realized with a small coating silver amount, a decrease in sensitivity caused by natural radiation upon storage of a raw photosensitive material or an increase in fogging density can be suppressed. As a result, a photographic color photosensitive material with good storage stability can be obtained.
1. A silver halide color photosensitive material comprising:
a support; and
a layer arrangement which is supported on said support and includes at least one blue-sensitive silver halide emulsion layer, a yellow filter layer, a high-speed red-sensitive silver halide emulsion layer, a high-speed green-sensitive silver halide emulsion layer, at least one low-speed green-sensitive silver halide emulsion layer, and at least one low-speed red-sensitive silver halide emulsion layer sequentially arranged adjacent to each other from the farthest side from said support in the order named, optionally with a non-photosensitive layer being interposed between adjacent color-sensitive emulsion layers.
a support; and
a layer arrangement which is supported on said support and includes at least one blue-sensitive silver halide emulsion layer, a yellow filter layer, a high-speed red-sensitive silver halide emulsion layer, a high-speed green-sensitive silver halide emulsion layer, at least one low-speed green-sensitive silver halide emulsion layer, and at least one low-speed red-sensitive silver halide emulsion layer sequentially arranged adjacent to each other from the farthest side from said support in the order named, optionally with a non-photosensitive layer being interposed between adjacent color-sensitive emulsion layers.
2. A silver halide color photosensitive material comprising:
a support; and
a layer arrangement which is supported on said sup port and includes at least one blue-sensitive silver halide emulsion layer, a high-speed red-sensitive silver halide emulsion layer, a high-speed green-sensitive silver halide emulsion layer, a low-speed green-sensitive silver halide emulsion layer, and a low-speed red-sensitive silver halide emulsion layer sequentially arranged adjacent to each other from the farthest side from said support in the order named, optionally with a non-photosensitive layer being interposed between adjacent color-sensitive emulsion layers and without a yellow filter layer.
a support; and
a layer arrangement which is supported on said sup port and includes at least one blue-sensitive silver halide emulsion layer, a high-speed red-sensitive silver halide emulsion layer, a high-speed green-sensitive silver halide emulsion layer, a low-speed green-sensitive silver halide emulsion layer, and a low-speed red-sensitive silver halide emulsion layer sequentially arranged adjacent to each other from the farthest side from said support in the order named, optionally with a non-photosensitive layer being interposed between adjacent color-sensitive emulsion layers and without a yellow filter layer.
3. The material according to claim 1, characterized in that said layer arrangement
comprises a low-speed red-sensitive silver halide emulsion layer, a medium-speed
red-sensitive silver halide emulsion layer, an interlayer, a low-speed green-sensitive
silver halide emulsion layer, a medium-speed green-sensitive silver halide emulsion
layer, a high-speed green-sensitive silver halide emulsion layer, an interlayer,
a high-speed red-sensitive silver halide emulsion layer, a yellow filter layer, a
low-speed blue-sensitive silver halide emulsion layer, a medium-speed blue-sensitive
silver halide layer, a high-speed blue-sensitive silver halide emulsion layer and
a protective layer arranged sequentially on a support in the order mentioned from
the closest side of said support.
4. The material according to claim 1, characterized in that said layer arrangement
comprises a low-speed red-sensitive silver halide emulsion layer, a medium-speed
red-sensitive silver halide emulsion layer, an interlayer, a low-speed green-sensitive
silver halide emulsion layer, a medium-speed green-sensitive silver halide emulsion
layer, an interlayer, a high-speed green-sensitive silver halide emulsion layer,
an interlayer, a high-speed red-sensitive silver halide emulsion layer, a yellow filter
layer, a low-speed blue-sensitive silver halide emulsion layer, a medium-speed blue-sensitive
silver halide emulsion layer, a high-speed blue-sensitive silver halide emulsion
layer and a protective layer sequentially arranged on said support in the order mentioned
from the closest side of said support.
5. The material according to claim 1, characterized in that said layer arrangement
comprises a low-speed red-sensitive silver halide emulsion layer, a medium-speed
red-sensitive silver halide emulsion layer, an interlayer, a low-speed green-sensitive
silver halide emulsion layer, a medium-speed green-sensitive silver halide emulsion
layer, an interlayer, a high-speed green-sensitive silver halide emulsion layer, an
interlayer, a high-speed red-sensitive silver halide emulsion layer, an interlayer,
a low-speed blue-sensitive silver halide emulsion layer, a medium-speed blue-sensitive
silver halide emulsion layer, a high-speed blue-sensitive silver halide emulsion layer,
and a protective layer sequentially arranged on said support in the order mentioned.
6. The material according to any one of claims 1 to 5, which has a specified photographic
sensitivity of 320 or more.
7. The material according to any one of claims 1 to 6, which contains a total of 3.0
to 13.0 g/m² of silver.