EP0146302A1

EP0146302A1 - Light-sensitive silver halide photographic material for direct-post and method for processing the same

Info

Publication number: EP0146302A1
Application number: EP84308402A
Authority: EP
Inventors: Kazuhiro Yoshida; Toshiharu Nagashima; Takeshi Murakami
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 1983-12-13
Filing date: 1984-12-04
Publication date: 1985-06-26
Also published as: JPH0435058B2; JPS60126645A

Abstract

@ A direct-posi light-sensitive silver halide photographic material, which comprises (i) having at least one layer of direct-posi silver halide emulsion layer containing silver halide grains having a silver halide composition containing 50 mol % or more of silver chloride on a support and (ii) containing a tetrazolium compound in at least one layer of said emulsion layer and/or the hydrophilic colloid layer existing on said support on the same side as said emulsion layer, and a method for processing the same.

Description

BACKGROUND OF THE INVENTION

This invention relates to a direct-posi light-sensitive silver halide photographic material, more particularly to a direct-posi light-sensitive silver halide photographic material capable of giving a posi-image by imparting previously fog and destroying fog by exposure utilizing the solarization or Herschel effect, and to a method for processing the same.
When producing a light-sensitive silver halide photographic material for direct-posi, which utilizes a light-source enriched in UV-rays, such as xenone, metal halide, mercury lamp or ultra-high pressure mercury lamp, for exposure, as the light-sensitive material of the type which can be handled under a fluorescent lamp for safety light from which UV-rays are cut, the reversal sensitivity of the light-sensitive material is lowered until it becomes approximate to the re-reversal sensitivity, whereby re-reversal tends to occur increasingly in practical application.
Such a tendency to give rise to re-reversal will appear strongly, particularly when employing a silver halide with higher silver chloride content, and it is required to increase silver bromide content in silver halide for improvement of such a tendency.
However, according to this improved method, softening of gradation becomes marked with the increase of silver bromide content to give disadvantageously no satisfactory photographic performance.
In particular, these drawbacks will appear markedly when processing with a developer for rapid processing containing a ultra-additive developing agent (Phenidone or Metol), whereby aptitude toward rapid processing is obstructed and the working efficiency during use of such a direct-posi light-sensitive silver halide photographic material is lowered.

SUMMARY OF THE INVENTION

An object of this invention is to provide a hard tone direct-posi light-sensitive silver halide photographic material, which can inhibit re-reversal generated by exposure and is low in Dmin.
Another object of this invention is to provide a direct-posi light-sensitive silver halide photographic material which is low in Dmin even by processing with a developer for rapid processing and can give photographic characteristics of hard contrast, and also a method for processing the same.
The above objects of this invention can be accomplished by a direct-posi light-sensitive silver halide photographic material, which comprises (i) having at least one layer of direct-posi silver halide emulsion layer containing silver halide grains having a silver halide composition containing 50 mol % or more of silver chloride on a support and (ii) containing a tetrazolium compound in at least one layer of said emulsion layer and/or the hydrophilic colloid layer existing on said support on the same side as said emulsion layer. It is preferable that the light-sensitive material according to this invention is processed with a method, which comprises processing the above light-sensitive material with a developer containing at least one compound represented by the formula [I] shown below:

Formula [I]
wherein Y is a nitrogen atom or a methyne group; Z is a nitrogen atom or a carbon atom; W is a sulfur atom, an oxygen atom or an imino group; V is a hydrogen atom or a mercapto group, with the proviso that at least one of Y and Z is a nitrogen atom, and, when Y represents a methyne group, W is an imino group; n is 0 or 1, being 0 when Z is a nitrogen atom or 1 when Z is a carbon atom; and Rl is a hydrogen atom, a lower alkyl group, a halogen atom or a nitro group.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This invention will be described in more detail below.
In the present invention, the above tetrazolium compound to be contained in the hydrophilic colloid layer may preferably be represented by the formulae [II] through [VI] shown below:
In the above formulae [II] through [VI], R₂ to R₁₈ each represent a group selected from the group consisting of alkyl groups (e.g. methyl, ethyl, propyl, tert-butyl, chloromethyl), alkenyl groups (e.g. allyl), aryl groups {e.g. phenyl, tolyl, hydroxyphenyl, alkoxyphenyl, carboxyphenyl, alkoxycarbonylphenyl, aminophenyl, mercaptophenyl, sulfoxyphenyl, aminosulfoxyphenyl, nitrophenyl, halogenated phenyl, etc., naphthyl (e.g. a-naphthyl, β-naphthyl, hydroxynaphthyl, carboxynaphthyl, amino- naphthyl, etc.)} and hyterocyclic groups (e.g. thiazolyl, benzothiazolyl, oxazolyl, pyrymidine, pyridyl, pyrazolyl, etc.), and each of these groups may be a group forming a metal chelate or complex.
Also, ^R ₄, R₇, R₁₀, R₁₂ and R₁₄ may be, in addition to those as mentioned above, a hydroxy group, an alkoxy group, a carboxy group, an alkoxycarbonyl group, a mercapto group, an alkoxysulfide group or a cyano group.
X^G represents an anion, which may be any anion generally known in the art.
D represents a divalent aromatic group such as phenylene group, and E represents a divalent group selected from, for example, an alkylene group, an arylene group and an aralkylene group.
m represents 1 or 2, with the proviso that m is 1, when the compound forms an intramolecular salt.
The anion represented by the above X" in the tetrazolium compound of this invention may be, for example, a halogen ion such as chloride ion, bromide ion, iodide ion, etc., an acid radical of an inorganic acid such as nitric acid, sulfuric acid, perchloric acid, etc., an acid radical of an organic acid such as a sulfonic acid or a carboxylic acid, etc., an anionic active agent, specifically a lower alkyl benzenesulfonic acid anion such as p-toluenesulfonic acid anion, etc., a higher alkyl benzenesulfonic acid anion such as p-dodecylbenzenesulfonic acid anion, etc., a higher alkyl sulfate anion such as lauryl sulfate anion, etc., a boric acid type anion such as tetraphenyl- boron, etc., a dialkylsulfosuccinate anion such as di-2-ethylhexylsulfosuccinate anion, etc., a polyether alcohol sulfate anion such as cetyl polyethenoxysulfate anion, etc., a higher fatty acid anion such as stearic acid anion, etc., and a polymer such as a polyacrylic acid anion to which an acid radical is attached.Exemplary tetrazolium compounds to be used in this invention are shown below, but the compounds which can be used in this invention are not limited to these.

(Exemplary compounds):

(1) 1,5-dimethyl-4-phenyl-lH-tetrazolium chloride;
(2) l,5-dimethyl-4-(3,4-xylyl)-tetrazolium chloride;
(3) 5-hydroxy-1,3-bis(p-nitrophenyl)-1H-tetrazolium chloride;
(4) 1,3,5-tri(p-carboxyethylphenyl)-1H-tetrazolium chloride;
(5) l-(benzthiazol-2-yl)-3-phenyl-5-(o-chlorophenyl)-2H-tetrazolium bromide;
(6) 4,5-dimethyl-l-phenyl-lH-tetrazolium chloride;
(7) 4,5-dimethyl-1-(3,4-xylyl)-1H-tetrazoliutn chloride;
(8) 3-(p-hydroxyphenyl)-5-methyl-1-phenyl-1H-tetrazolium bromide;
(9) 1,3-diphenyl-5-ethyl-lH-tetrazolium bromide;
(10) l,3-diphenyl-5-n-hexyl-lH-tetrazolium bromide;
(11) 5-cyano-1,3-diphenyl-1H-tetrazolium bromide;
(12) 1,4,5-triphenyl-lH-tetrazolium chloride;
(13) l-(benzothiazol-2-yl)-5-(4-chlorophenyl)-3-(4-nitrophenyl)-lH-tetrazolium chloride;
(14) 5-hydroxy-1, 3-diphenyl-1H-tetrazolium hydroxide intramolecular salt;
(15) 5-acetyl-1,3-di(p-ethoxyphenyl)-lH-tetrazolium bromide;
(16) 1,5-diphenyl-3-(p-tolyl)-lH-tetrazolium chloride;
(17) l,5-diphenyl-3-(p-iodophenyl)-lH-tetrazolium chloride;
(18) 1,3-diphenyl-5-(p-diphenyl)-lH-tetrazolium chloride;
(19) 5-(p-(p-acetamidoanilino)phenylazo]-1,4-dimethyl-1H-tetrazolium chloride;
(20) 5-(p-dimethylaminostyryl)-4-ethyl-l-phenyl-lH-tetrazolium chloride;
(21) 3,5-diallyl-l-(tetrazol-5-yl)-lH-tetrazolium chloride;
(22) 1-cyclohexyl-4,5-dimethyl-lH-tetrazolium chloride;
(23) 3-(p-acetamidophenyl)-1,5-diphenyl-1H-tetrazolium bromide;
(24) 5-acetyl-l,3-diphenyl-lH-tetrazolium bromide;
(25) 1-(m-chlorophenyl)-4,5-dimethyl-lH-tetrazolium chloride;
(26) l-cyclohexyl-4,5-dimethyl-lH-tetrazolium chloride;
(27) 1-(o-chlorophenyl)-4,5-dimethyl-1H-tetrazolium chloride;
(28) 1-(p-bramophenyl)-4,5-dimethyl-1H-tetrazolium chloride;
(29) 4,5-dimethyl-1-p-tolyl-1H-tetrazolium chloride;
(30) 2-(benzothiazol-2-yl)-3-phenyl-5-dodecyl-2H-tetrazolium bromide;
(31) 2,3-diphenyl-5-(4-t-octyloxyphenyl)-2H-tetrazolium chloride;
(32) 2,3,5-triphenyl-2H-tetrazolium chloride;
(33) 2,3,5-tri(p-carboxyethylphenyl)-2H-tetrazolium-2,2-diethylhexylsuccinate;
(34) 2-(benzothiazol-2-yl)-3-phenyl-5-(o-chlorophenyl)-2H-tetrazolium chloride;
(35) 2,3-diphenyl-2H-tetrazolium chloride;
(36) 2,3-diphenyl-5-methyl-2H-tetrazolium chloride;
(37) 3-(p-hydroxyphenyl)-5-methyl-2-phenyl-2H-tetrazolium chloride;
(38) 2,3-diphenyl-5-ethyl-2H-tetrazolilum chloride;
(39) 2,3-diphenyl-5-n-hexyl-2H-tetrazolium chloride;
(40) 5-cyano-2,3-diphenyl-2H-tetrazolium diisopropyl- naphthalene sulfonate;
(41) 2-(benzothiazol-2-yl)-3-phenyl-3-(4-tolyl)-2H-tetrazolium chloride;
(42) 2-(benzothiazol-2-yl)-5-(4-chlorophenyl)-3-(4-nitrophenyl)-2H-tetrazolium chloride;
(43) 5-ethoxycarbonyl-2,3-di(3-nitrophenyl)-2H-tetrazolium-1-methyl-benzotriazole sulfonate;
(44) 5-acetyl-2,3-di(p-ethoxyphenyl)-2H-tetrazolium chloride;
(45) 2,5-diphenyl-3-(p-tolyl)-2H-tetrazolium-2-mercapto- benzoxazole sulfonate;
(46) 2,5-diphenyl-3-(p-iodophenyl)-2H-tetrazolium chloride;
(47) 2,3-diphenyl-5-(p-diphenyl)-2H-tetrazolium chloride;
(48) 5-(p-bromophenyl)-2-phenyl-3-(2,4,6-trichlorophenyl)-2H-tetrazolium chloride;
(49) 3-(p-hydroxyphenyl)-5-(p-nitrophenyl)-2-phenyl-2H-tetrazolium chloride;
(50) 5-(3,4-dimethoxyphenyl)-3-(2-ethoxyphenyl)-2-(p-methoxyphenyl)-2H-tetrazolium chloride;
(51) 5-(4-cyanophenyl)-2,3-diphenyl-2H-tetrazolium chloride;
(52) 3-(p-acetamidophenyl)-2,5-diphenyl-2H-tetrazolium chloride;
(53) 5-acetyl-2,3-diphenyl-2H-tetrazolium chloride;
(54) 5-(fur-2-yl)-2,3-diphenyl-2H-tetrazolium chloride;
(55) 5-(thien-2-yl)-2,3-diphenyl-2H-tetrazolium chloride;
(56) 2,3-diphenyl-5-(quinol-2-yl)-2H-tetrazolium chloride;
(57) 2,3-diphenyl-5-(benzoxazol-2-yl)-2H-tetrazolium chloride.

The tetrazolium compounds to be used in this invention can readily be synthesized according to, for example, the methods as disclosed in Chemical Reviews, THE WILLIAM & WILKINS COMPANY, Vol. 55, p. 355 - 483.
The tetrazolium compound to be used in this invention may be used singly to give more preferably characteristics, but a pluralty of compounds can be combined at any ratio without deteriorating the preferable characteristics.
As a preferred embodiment of this invention, it is possible to add the tetrazolium compound of this invention into the silver halide emulsion layer. According to another embodiment of this invention, it is added into the hydrophilic colloid layer adjacent directly or through an intermediate layer to the hydrophilic colloid layer containing the silver halide emulsion layer.
As still another embodiment, a solution of a tetrazolium compound of this invention in a suitable organic solvent, such as alcohols (e.g. methanol, ethanol), ethers, esters, etc., may be applied by the overcoating method, etc. directly on the portion of the outermost layer of the light-sensitive material to incorporate the compound in the light-sensitive material of this invention.
The tetrazolium compound to be used in this invention should preferbly be employed in an amount within the range from 1 x 10 ⁶ mol to 5 x 10-¹ mol, particularly from 1 x 10-5 mol to 1 x 10-2 mol per mol of the silver halide contained in the light-sensitive material of this invention.
The silver halide to be used in this invention may include silver chloride, silver chlorobromide, silver chloroiodide, silver chloroiodobromide and the like. In any case, it is required that the silver chloride should be contained at a proportion of at least 50 mol %. If the silver chloride content is less than 50 mol %, the contrast hardening effect of this invention will undesirably be lost. On the other hand, if it exceeds 95 mol %, re-reversal will be generated intensely. Accordingly, in view of various photographic performances, in one of preferred embodiments, the silver chloride content may be 50 mol % - 95 mol %.
The above silver halide emulsion containing 50 mol % or more of silver chloride can be prepared by, for example, any of the acidic method, the neutral method or the ammonia method, according to the conventional techniques known in the art, including simultaneous mixing, reverse mixing, ordinary mixing, etc. Further, if desired, it can be prepared while controlling the flow rate at which it is to be added, pH or EAg.
The silver halide to be incorporated in the silver halide emulsion layer of this invention is not limited, but it should desirably contain a silver halide having an average grain size of 0.05 to 1.5 micron, preferably 0.1 to 0.5 micron, and with at least 75 %, preferably 80 % or more of all the grain number comprising those having 0.5 to 1.5-fold, preferably 0.6 to 1.4-fold of the aforesaid average grain size.
According a most preferred embodiment of this invention, the silver halide of this invention may be silver chlorobromide having an average grain size of 0.1 to 0.3 ^p, and 80 % or more of all the grains have grain sizes of 0.6 to 1.4-fold of the average grain size.
In the silver halide emulsion layer according to this invention, an organic desensitizer may be added, and such organic desensitizers may include, for example, 7- membered ring commpounds as disclosed in Japanese Patent Publication No. 14500/1968, fluorene compounds having a nitro group as disclosed in Japanese Unexamined Patent Publication No.84432/1974, compounds having a nitro- phenylmercapto group as disclosed in U.S.Patent 3,910,795, nitrostyryl compounds, pinacryptol yellow, 5-m-nitrobenzylidene rhodanineas as disclosed in U.S. Patent 2,669,515, etc. These organic desensitizers may be added in amounts of 1.0 x 10^-6 mol to 1.0 x 10^-1 mol, preferably 1.0 x 10-⁵ mol to 1.0 x 10 ² mol per mol of the silver halide.
It is also possible to incorporate atoms such as of iridium, rhodium, osmium, bismuth, cobalt, nickel, palladium, ruthenium, iron, copper, zinc, lead, etc. within the crystalline grains of silver halide. When these atoms are to be contained, they should preferably be contained in amounts of 10^-9 to 10^-2 mole, particularly 10^-6 to 10-3 mol per mol of the silver halide. Either surface latent image type or internal latent image type may be available. Further, silver halides prepared according to different methods may be mixed together. The crystal form is not limited at all, but either cubic, octahedral or spherical may be available.
The direct-posi silver halide emulsion to be used in this invention is endowed with fogging before exposure according to the technique known in the art. Fog can be imparted with a reducing agent alone or a combination of a reducing agent and a gold compound. Representatives of useful reducing agents are, for example, formalin, hydrazine, polyamine (e.g. triethylenetetramine, tetraethylenepentamine, etc.), thiourea dioxide, tetra-(hydroxymethyl)phosphonium chloride, boron compounds (e.g. amine borane, sodium borohydride, etc.) and stannous chloride, and they are used generally in amounts of 2.0 x 10^-6 to 2.0 x 10^-3 per mol of the silver halide. In particular, polyaminethiourea dioxide and boron compounds may preferably be employed. Typical examples of the above gold compounds include chloroauric acid, potassium chloroaurate, gold sulfide, gold selenide, etc., which can be used in amounts generally from 1.0 x 10^-6 to 1.0 x 10 ⁴ mol per mol of the silver halide.
The degree of the fog to be imparted to the direct-posi silver halide of this invention can be chosen suitably depending on the amount of the fogging agent, and the temperature and time conditions of fogging-ripening.
The aforesaid silver halide and the tetrazolium compound of this invention is contained in a hydrophilic colloid layer. The hydrophilic colloid to be used particularly advantageously in this invention is gelatin, but hydrophilic colloids other than gelatin may include, for example, colloidal albumin, agar, gum arabic, alginic acid, hydrolyzed cellulose acetate, acrylamide, imidated polyamide, polyvinyl alcohol, hydrolyzed polyvinyl acetate, gelatin derivatives such as phenylcarbamyl gelatin, acylated gelatin, phthalated gelatin as disclosed in U.S. Patents 2,614,982 and 2,525,753, or graft polymers having polymerizable monomers with ethylenic groups such as acrylic acid, styrene, acrylates, methacrylic acid, methacrylates, etc. grafted to gelatin, as dislcosed in U.S. Patents 2,548,520 and 2,831,767. These hydrophilic colloids are also applicable for layer containing no silver halide such as the halation prevention layer, the protective layer, the intermediate layer, etc.
The light-sensitive material of this ivnention comprises a hydrophilic colloid layer containing the silver halide and the tetrazolium compound according to this invention provided by coating on a suitable support for photography. The support to be used in this invention may include typically baryta paper, polyethylene-coated paper, polypropylene synthetic paper, glass plate, cellulose acetate, cellulose nitrate, polyester films such as polyethylene terephthalte, polyamide film, polypropylene film, polycarbonate film, polystyrene film, etc. These supports can be chosen suitable depending on the end of use of the respective light-sensitive materials.
The light-sensitive material, which comprises at least one hydrophilic colloid layer containing the silver halide and the tetrazolium compound according to the present invention provided by coating on a support, should desirably have a protective layer having an appropriate thickness, namely 0.1 to 10 p, particularly a gelatin protective layer having a 0.8 to 2 p thickness, provided by coating.
The above hydrophilic colloid to be used in this invention may also employ, if desired, various additives for photography, such as gelatin plasticizers, film hardeners, surfactants, image stabilizers, UV-absorbers, anti-stain agents, pH controllers, antioxidants, antistatic agents, thickeners, graininess enhancers, dyes, mordants, whitening agents, developing speed controllers, matting agents, etc. within the ranges which will not damage the effect of this invention.
Of the various additives as mentioned above, those which can be used particularly preferably for this invention may include, as the thickeners or plasticizers, the substances disclosed in U.S. Patent 2,960,404, Japanese Patent Publication No.4939/1968, German ALS 1 904 604, Japanese Patent Publication No.63715/1973, Japanese Patent Publication No.15462/1970, Belgian Patent 762,833, U.S.Patent 3,767,410 and Belgian Patent 558,143, such as styrene-sodium maleate copolymers, dextran sulfate, etc.; as film hardeners, various kinds of film hardners of aledehyde type, epoxy type, ethyleneimine type, active halogen type, vinylsulfone type, isocyanate type, sulfonic acid ester type, carbodiimide type, mucochloric acid type, acyloyl type, etc.; as UV-absorbers, compounds as disclosed in U.S. Patent 3,253,921 and U.K. Patent 1,309,349, particularly 2-(2'-hydroxy-5-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-5'-di-tert-butylphenyl)-5-chlorobenzotriazole and the like; as dyes, compounds as disclosed in U.S. Patent 2,072,908, German Patent 107 990, U.S. Patent 3,048,487 and U.S. Patent 515,998. These compounds may be incorporated in the protective layer, the emulsion layer or the intermediate layer. Further, as the surfactants to be used for improving penetrability for coating aids, emulsifying agents, processing liquors, etc., as defoaming agents or for controlling various physical properties of the light-sensitive material, there may be employed anionic, cationic, nonionic or amphoteric compounds as disclosed in U.K. Patents 548,532 and 1,216,389, U.S. Patents 3,026,202 and 3,514,293, Japanese Patent Publications Nos. 26580/1969, 17922/1968, 17926/1968, 13166/1968 and 20785,1973, French Patent 202,588, Belgian Patent 773,459, and Japanese Unexamined Patent Publication No.101118. Available antistatic agents may include the compounds as disclosed in Japanese Patent Publication No.24158/1971, Japanese Unexamined Patent Publication No.89979/1973, U.S. Patents 2,882,157 and 2,972,535, Japanese Unexamined Patent Publications Nos. 20785/1973, 43130/1973 and 90391/1973, Japanese Patent Publication Nos. 24159/1971, 39312/1971 and 43809/1973, and Japanese Unexamined Patent Publication No. 83627/1972. Matting agents are inclusive of the compounds as disclosed in U.K. Patent 1,221,980, U.S. Patents 2,992,101 and 2,956,884, French Patent 1,395,544 and Japanese Patent Publication No.43125/1973, particularly silica gel having particle sizes of 0.5 to 20 u and polymethyl methacrylate polymers having particle sizes of 0.5 to 20 µ.
The emulsion layer and other constituent layers in the light-sensitive material of this invention can be coated according to various coating methods known in the art. The coating method includes the dipping coating method, the air-knife coating method, the roller coating, the curtain coating and extrusion coating method. The method disclosed in U.S. Patent 2,681,294 is one of advantageous methods. Two or more layers can be coated simultaneously by use of the method as disclosed in U.S. Patents 2,761,791 and 3,526,528.
Next, a preferred method for processing the light-sensitive material according to this invention will be showm below.
The light-sensitive material of this invention is treated with a developer containing at least one compound represented by the formula [I] shown below:

Formula [I]:
wherein Y is a nitrogen atoms or a methyne group, Z is a nitrogen atom or a carbon atom, W is a sulfur atom, oxygen atom or an imino group, V is a hydrogen atom or a mercapto group, with the proviso that at least one of Y and Z is a nitrogen atom and, when Y represents a methyne group, W is an imino group, n is 0 or 1, when Z is a nitrogen atom, n is zero, and when Z is a carbon atom, n is 1, R1 is a hydrogen atom, a lower alkyl group, a halogen atom or a nitro group.

Typical examples of the compounds represented by the above formula [I] are enumerated below, but this invention is not limited to the use of these compounds.

(a - 1) benzotriazole;
(a - 2) 4-methylbenzotriazole;
(a - 3) 5-bromobenzotriazole;
(a - 4) 5-nitrobenzotriazole;
(a - 5) 5-ethylbenzotriazole;
(a - 6) benzimidazole;
(a - 7) 5-chlorobenzimidazole;
(a - 8) 5-nitroindazole;
(a - 9) 6-nitroindazole;
(a - 10) 5-methylbenzoindazole.

The compounds represented by the above formula [I] are generally known as development inhibitors, and these development inhibitors should preferably be employed in amounts of 10^-1 to 10-⁵ mol, particularly 10-² to ₁₀ ⁴ mol per liter of the developer. It is also preferred to dissolve the above development inhibitor in an alkanol amine and/or a glycol prior to addition into the developer.
In the processing method of the direct-posi light-sensitive photographic material of this invention, the developing agents to be incorporated in the developer include the following.
As the HO-(CH₌CH)_n-OH type developing agent, there may be employed hydroquinone, catechol, pyrogalol and derivatives thereof, and also ascorbic acid as representative ones, including hydroquinone, chlorohydroquinone, bromohydroquinone, isopropyl hydroquinone, toluhydro- quinone, methylhydroquinone, 2,3-dichlorohydroquinone, 2,5-dimethylhydroquinone, 2,3-dibromohydroquinone, 2,5-dihydroxyacetophenone, 2,5-diethylhydroquinone, 2,5-di-p-phenethylhydroquinone, 2,5-dibenzoylaminohydro- quinone, catechol, 4-chlorocatechol, 3-phenylcatechol, 4-phenylcatechol, 3-methoxycatechol, 4-acetylpyrogalol, 4-(2-hydroxybenzoyl)pyrogalol, sodium ascorbate, and the like.
As the HO-(CH=CH)_n-_NH₂ type developing agent, there may be employed ortho- or para-amino phenol or amino- pyrazolone as representative ones, including 4-aminophenol, 2-amino-6-phenylphenol, 2-amino-4-chloro-6-phenylphenol, 4-amino-2-phenylphenol, 3,4-diaminophenol, 3-methyl-4,6-diaminophenol, 2,4-diaminoresorcinol, 2,4,6- triaminophenol, N-methyl-p-aminophenol, N-S-hydroxyethyl- p-aminophenol, p-hydroxyphenyl aminoacetic acid, 2-amino- naphthol and the like.
As the H₂N-(CH=CH)_n-NH₂ type developing agent, there may be employed, for example, 4-amino-2-methyl-N,N-diethylaniline, 2,4-diamino-N,N-diethylaniline, N-(4-amino-3-methylphenyl)morpholine, p-phenylenediamine, 4-amino-N,N-dimethyl-3-hydroxyaniline, N,N,N'N'-tetramethylpara- phenylenediamine, 4-amino-N-ethyl-N-(S-hydroxyethyl)-aniline, 4-amino-3-methyl-N-ethyl-N-(β-hydroxyethyl)-aniline, 4-amino-N-ethyl-(S-methoxyethyl)-3-methylaniline, 4-amino-3-methyl-N-ethyl-N-(β-methylsulfonamido- ethyl)aniline, 4-amino-N-butyl-N-y-sulfobutylaniline, 1-(4-aminophenyl)pyridine, 6-amino-l-ethyl-1,2,3,4-tetrahydroquinoline, 9-aminoeurhodine and others.
The heterocyclic developing agent may include, for example, I-phenyl-3-pyrazolidone (phenidone), 4,4'-dimethyl-1-phenyl-pyrazolidone (dimezone), l-phenyl-4-amino-5-pyrazolone, 1-(p-aminophenyl)-3-amino-2-pyrazoline, l-phenyl-3-methyl-4-amino-5-pyrazolone, 5-aminouracil, 5-amino-2,4,6-trihydroxyphylimidene, etc.
Otherwise, the developers as disclosed in T.H. James, "The Theory of the Photographic Process, Fourth Edition", items 291 - 334 and Journal of the American Chemical Society, Vol. 73, item 3100 (1951) can be used effectively in this invention. These developers may be used either singly or as a combination of two or more compounds, the latter being preferred.
Preferable combinations are hydroquinone and phenidone or hydroquinone and dimezone, and it is preferable to use hydroquinone in an amount of 5 g to 50 g/liter, while phenidone or dimezone in an amount of 0.05 to 5 g/liter. Also, in the developer to be used in this invention, it is possible to employ a preservative, for example, a sulfite such as sodium sulfite, potassium sulfite, ammonium sulfite, etc. without damaging the effect of this invention. This may be reckoned as one specific feature of this invention. The sulfite concentration may preferably be 0.06 to 1 gram ion/liter. Also, hydroxyamine or a hydrazide compound may be available as the preservative. Otherwise, it may freely be practiced to impart the function of controlling pH and buffering with a caustic alkali, a carbonate alkali or an amine as employed generally in black-and-white developer, and to add an inorganic development inhibiting agent such as potassium bromide, a metal ion capturing agent such as ethylene-diaminetetraacetic acid, a development accelerator such as methanol, ethanol, benzyl alcohol, polyalkylene oxide, etc., a surfactant such as sodium alkyl aryl sulfonate, natural saponin, sugars or alkyl esters of the aforesaid compound, etc., film hardener such as glutaraldehyde, formalin, glyoxal, etc., or an ion strength controlling agent such as sodium sulfate, etc.
The pH value may be adjusted as desired at 9 to 12, but the range from pH 10 to 11 is preferred in view of preservation characteristic and photographic performance.
The developer according to this invention may also contain an organic solvent selected from alkanol amines or glycols, if desired.
The above alkanol amines may be, for example, monoethanol amine, diethanol amine, triethanol amine. Preferably, triethanol amine is employed. These alkanol amines may be employed preferably in an amount of 20 to 500 g, particularly preferably 60 to 300 g, per liter of the developer.
The above glycols may include ethylene glycol, diethylene glycol, propylene glycol, triethylene glycol, 1,4-butane diol, 1,5-pentane diol and the like. Preferably, ethylene glycol is employed. These glycols may be employed preferably in an amount of 20 to 500 g, particularly 60 to 300 g, per liter of the developer.
The above alkanolamines and glycols may be used either singly or as a combination of two or more compounds.
In the method for processing of the direct-posi light-sensitive photographic material of this invention, processing may be conducted according to various conditions. The processing temperature, for example, the developing temperature may preferably 50 °C or lower, particularly preferably around 30 °c, while developing may generally be completed within 3 minutes, particularly preferably within 2 minutes to give frequently favorable results. The processing steps other than development, for example, washing, stopping, stabilizing and fixing, and further the steps of prehardening, neutralization, etc., if desired, may be freely employed, and these steps can also be omitted depending on the occasion. Further, these processings may be either the so called manual developing processing such as tray developing or frame developing or mechanical developing such as roller developing or hanger developing.
The light-sensitive material of this invention and its preferred processing method as described in detail above can accomplish completely the objects of this invention. For example, when the printing evaluation onto a printing plate was performed by use of the thus obtained light-sensitive silver halide photographic material for photoengraving, a printing plate having dot quality with low Dmin (minimum density) and excellent sharpness in its finishing was found to be prepared.
This invention is described in more detail by referring to the following Examples, by which the technical scope of this invention is not limited at all, but a variety of embodiments can be practiced.

Example 1

Various silver chlorobromide emulsions were prepared by adding a solution of rhodium chloride (RhCl₃ 3H₂O) dissolved in a sodium chloride solution to silver halide in an amount of 3 x 10^-4 mol per mol of silver halide, and varying the silver chloride content as indicated in Table 1, each according to the simultaneous mixing method at 45 °c over 30 minutes.
Each emulsion as prepared above was desalted and redispersed to prepare a mono-dispersed emulsion. To this mono-dispersed emulsion was added 10 mg of thiourea dioxide per mol of the silver halide, the resultant mixture was ripened at 60 °c for 60 minutes, followed by ripening at 60°C with addition of 3 mg of chloroauric acid per mol of the silver halide until the highest performance is attained to form fog.
The emulsion endowed with fog thus obtained was divided into 5 equal portions, which were then formulated into coating solution recipes E₁ to E₅ as shown below.
Preparation of coating solution E_l:

To one of the five equal portions of the emulsion, 1 g of 5-nitrobenzimidazole per mol of the silver halide and 1 g of p-nitrophenol-di-phenylphosphonium chloride per mol of the silver halide as the inhibitor, 4 g of an aqueous 20 % saponin solution as the coating aid per mol of the silver halide, 5 g of a styrene-maleic acid copolymer as the thickener per mol of the silver halide and formaldehyde and glyoxal as the film hardener were added, and the mixture was made up to 1.5 liter to prepare a coating solution.

Preparation of coating solution E₂:

Following the same procedure as in preparation of the coating solution E₁, except for further adding 5 x 10^-4 mol per mol of the silver halide of the exemplary compound (32) in an aqueous solution in addition to the additives in E1 and making up the mixture to 1.5 liter per mol of the silver halide, a solution E₂ was prepared.

Preparation of coating solution E₃:

This solution was prepared, following the same procedure as in preparation of the coating solution E₂, except for substituting 5 x 10^-4 mol per mol of the silver halide of the exemplary compound (12) as 1 % methanolic solution for the exemplary compound (32).

Preparation of coating solution E₄ ^:

This solution was prepared similarly as in preparation of the coating solution of E₃, except for adding the equal mol of the exemplary compound (39) as the tetrazolium compound in place of the exemplary compound (12).

Preparation of coating solution E₅:

This solution was prepared similarly as in preparation of the coating solution of E₄, except for adding the equal mol of the exemplary compound (45) as the tetrazolium compound in place of the exemplary compound (39).

Next, P_l solution shown below was prepared as the coating solution for protective film for emulsion.
Preparation of P₁ solution:

To 1 kg of gelatin were added 10 liters of pure water, and the swelled gelatin was heated to 40 °C, followed by addition of 3 liters of 1 % aqueous solution of sodium diethylsulfosuccinate sulfonate as the coating aid and one liter of an aqueous 10 % solution of a filter dye having the formula f_l shown below. Further, as the matting agent, 40 g of fine powder of silica gel with an average particle size of 4 µ was added by dispersing into gelatin, formaldehyde was added as the film hardener and the mixture was made up to 20 liters.

(Filter dye f₁) :
Next, the back coating solution B₁ was prepared as follows.
Preparation of B₁ solution:

Into 1 kg of gelatin were added 20 liters of pure water, and the swelled gelatin was heated to 40 °C, followed by addition of 800 cc of aqueous 10 % solution of the above dye f₁ employed for the P₁ solution as additive, and further 16 g of a styrene-maleic acid copolymer as the thickener and 16 g of sodium dipropylnaphthalene- disulfonate as the coating aid, and the mixture was made up with pure water to 30 liters.

Preparation of protective coating solution for back:

P₂ solution was prepared similarly as in preparation of the protective film coating solution for emulsion, except for removing the above dye f_l from P₁ solution.

Preparation of light-sensitive silver halide photographic material:

After applying simultaneously in overlayers a combination of the back coating solution _Bi and the protective film solution P₂ therefor on a polyethylene terephthalate applied with subbing treatment, with gelatin being attached in an amount of 2g/m² in the former and lg/m² in the latter, a combination of the emulsion coating solution and the protective film solution therefor were applied similarly on the opposite side, with the silver quantity being 3 g/m² (gelatin attached 2 g/m²) and the gelatin attached in the protective film 1 g/m². During coating, the protective film was hardened with a hardening agent employing in combination the three kinds of formaldehyde, mucochloric acid and ethyleneimine.

Each of the above test samples was exposed by use of a step-wedge in a UV-ray light room printer employing a ultra-high pressure mercury lamp as the light source (HMW-215 produced by ORC manufacturing Co.), and separately subjected to contact printing by use of halftone dot photographic original with a darkened degree of about 50 %, and exposure was effected to the darkened degree of the test sample of about 50 %.
The exposed test sample was processed under the conditions shown below by charging the developer of the recipe shown below and a commercial available fixing solution into a roller conveying type automatic developing machine (developer tank capacity: 40t ).
The developer was made up to one liter by dissolving 500 ml of the stock solution of the developer shown below in 500 ml of pure water before use.

(Processing conditions)

[Developer]

After the light-sensitive material prepared as described above was printed by a 2 KW metal halide lamp on Sakura PS plate SPP for proofreading and processed by PS-plate automatic developing machine (with the use of Sakura PS-plate developer), re-reversal, Dmin of dot and sharpness of dot were evaluated by observation with eyes to obtain the results shown in Table 1.
The standards for characteristic evaluation in Table 1 are as shown below.

A: best
B: good
C: slightly inferior
D: inferior

As apparently seen also from the results shown in the above Table, the samples of this invention (Sample Nos. 6, 7, 9, 10, 12, 13, 14, 15, 17, 18, 20 and 21) containing 50 mol % or more of silver chloride and tetrazolium compounds according to this invention can be understood to give excellent finishing with inhibition of re-reversal, low Dmin and excellent sharpness of dot, as comapred with Control samples.

Example 2

Light-sensitive materials were prepared in the same manner as in Example 1, but developers were prepared by adding the compounds shown in Table 2 in amounts prescribed in the Table in place of 5-methylbenzotriazole, I-phenyl-5-mercaptotetrazole and 5-nitroindazole employed in Example 1.
Next, the test sample No. 8 prepared in Example 1 was exposed similarly as in Example 1 by a UV-ray light room printer (HMW-215 produced by ORC manufacturing Co.) employing a ultra-high pressure mercury lamp as the light source. Subsequently, developing processing was performed with a developer containing the compounds in the Table shown below.

Evaluation of the samples after processing was conducted similarly as in Example 1.

The results are shown in Table 3.
As can clearly be seen also from the above Table, by use of the developer containing the development inhibitor according to this invention, it can be understood that re-reversal can be inhibited, and a silver image excellent in Dmin of dot and sharpness can be obtained.

Example 3

An emulsion was prepared following the same procedure as in Example 1, but without addition of rhodium chloride, and subjected to ripening to form fog. This emulsion was divided into 5 equal portions, and coating solutions were prepared according to the recipes E₁ through E₅. However, into each solution was added pinakryptol yellow in methanolic solution in an amount of 1 g per mole of the silver halide. Subsequently, following the same steps of Example 1, exposure and processing were conducted. Evaluation of the image obtained gave the result that the samples employing the emulsions containing tetrazolium compounds according to this invention are inhibited in re-reversal, and finishing with low Dmin and excellent sharpness could be obtained.
By the light-sensitive photographic material of this invention, the above objects of this invention can be accomplished, whereby Dmin of dot and sharpness of the dot can be improved. And, further, the above effects can be still promoted by processing with a developer containing a compound represented by the aforementioned formula [I].

Claims

1. A direct-posi light-sensitive silver halide photographic material, which comprises (i) having at least one layer of direct-posi silver halide emulsion layer containing silver halide grains having a silver halide composition containing 50 mol % or more of silver chloride on a support and (ii) containing a tetrazolium compound in at least one layer of said emulsion layer and/or the hydrophilic colloid layer existing on said support on the same side as said emulsion layer.

2. The direct-posi light-sensitive silver halide photographic material according to Claim 1, wherein the content of silver chloride in said silver halide grains is 50 to 95 mol %.

3. The direct-posi light-sensitive silver halide photographic material according to Claim 2, wherein the content of silver chloride in said silver halide grains is 50 to 90 mol %.

4. The direct-posi light-sensitive silver halide photographic material according to Claim 3, wherein the content of silver chloride in said silver halide grains is 70 to 85 mol %.

5. The direct-posi light-sensitive silver halide photographic material according to Claim 1, wherein the tetrazolium compound is at least one selected from the compounds represented by the formulae [II] through [VI] shown below:

wherein R₂ to R₁₈ each represent a group selected from the group consisting of alkyl groups, alkenyl groups, aryl groups and heterocyclic groups, each of which may be a group forming a metal chelate or complex; R4, R₇, R₁₀, R₁₂ and R₁₄ may be, in addition to the respective groups as mentioned above, a hydroxy group, an alkoxy group a carboxy group, an alkoxycarbonyl group, a mercapto group, an alkoxysulfide group or a cyano group; X^⊖ represents an anion; D represents a divalent aromatic group; E represents a divalent group; m represents 1 or 2, with the proviso that m is 1 when the compound forms an intramolecular salt.

6. The direct-posi light-sensitive silver halide photographic material according to Claim 2, wherein said tetrazolium compound is contained at a proportion of 1 x 10^-6 mol to ₅ x 10^-1 mol per mol of saidhe silver halide grains.

7. The direct-posi light-sensitive silver halide photographic material according to Claim 2, wherein said tetrazolium compound is at least one of the compounds represented by the formulae [II] through [VI] shown below:.

wherein R₂ to R₁₈ each represent a group selected from the group consisting of alkyl groups, alkenyl groups, aryl groups and heterocyclic groups, each of which may be a group forming a metal chelate or complex; ^R4, R₇, R₁₀, R₁₂ and R₁₄ may be, in addition to the respective groups as mentioned above, a hydroxy group, an alkoxy group a carboxy group, an alkoxycarbonyl group, a mercapto group, an alkoxysulfide group or a cyano group; X⁹ represents an anion; D represents a divalent aromatic group; E represents a divalent group; m represents 1 or 2, with the proviso that m is 1 when the compound forms an intramolecular salt.

8. The direct-posi light-sensitive silver halide photographic material according to Claim 2, wherein said silver halide grains have a mean grain size of 0.1 to 0.3 p, and 80 % or more of the grains (in number) in the emulsion have a grain size within the range from 0.6 to 1.4-fold of said mean grain size.

9. A method for processing a light-sensitive direct-posi silver halide photographic material, which comprises processing a direct-posi light-sensitive silver halide photographic material, having at least one layer of direct-posi silver halide emulsion layer containing silver halide grains having a silver halide composition containing 50 mol % or more of silver chloride on a support and containing a tetrazolium compound in at least one layer of said emulsion layer and/or the hydrophilic colloid layer existing on said support on the same side as said emulsion layer, with a developer containing at least one compound represented by the formula [I] shown below:

wherein Y is a nitrogen atom or a methyne group; Z is a nitrogen atom or a carbon atom; W is a sulfur atom, an oxygen atom or an imino group; V is a hydrogen atom or a mercapto group, with the proviso that at least one of Y and Z is a nitrogen atom, and, when Y represents a methyne group, W is an imino group; n is 0 or 1, being 0 when Z is a nitrogen atom or 1 when Z is a carbon atom; and R is a hydrogen atom, a lower alkyl group, a halogen atom or a nitro group.

10. The method according to Claim 9, wherein the content of the compound represented by said formula [I] is 10-¹ to 10^-5 mol per liter of the developer.