JPH063532B2 - Method for producing silver halide emulsion and photographic light-sensitive material - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a silver halide emulsion and a silver halide photographic light-sensitive material using the same, and more specifically, tabular silver halide grains. The present invention relates to a method for sensitizing a photographic emulsion containing a spectral sensitizer and a silver halide photographic light-sensitive material containing a tabular silver halide emulsion prepared by such a method.

(Prior Art) In order to increase the sensitivity of silver halide grain emulsions, it is well known to increase the grain size of the grains.
However, along with this, the fog increases and the graininess deteriorates.

A tabular silver halide grain emulsion is disclosed in JP-A-58-11392.
As disclosed in No. 6, the sensitivity / granularity ratio is better than that of the other shaped grain emulsions, and the large specific surface area is considered to be advantageous for the spectral sensitization by the spectral sensitizer. High sensitivity is obtained by using a spectral sensitizer even when the main absorption is found in the spectral region where the emulsion exhibits its original sensitivity. However, if the particle size is increased to further increase the sensitivity, the graininess is deteriorated accordingly. Moreover, even if one attempts to sensitize by increasing the addition amount of the spectral sensitizer by activating the large specific surface area which is characteristic of the tabular grain emulsion, the spectral sensitizer of Large intrinsic desensitization occurs with the addition amount. The degree of desensitization is often greater than that of other shaped grain emulsions. 50% of the amount that can cover the entire surface with tabular grains
When the above spectral sensitizers are added, this intrinsic desensitization often becomes large, and when the amount added is 75% or more, a markedly large desensitization occurs, and the characteristics of tabular grains are not always essential. It is technically important.

On the other hand, the spectral sensitization technique is an extremely important and essential technique for producing a light-sensitive material having high sensitivity and excellent color reproducibility. While various spectral sensitizers have been developed so far in order to provide high-sensitivity light-sensitive materials, many technical developments have been made in their use by their supersensitization method and addition method. Spectral sensitizers have the function of absorbing light in the long wavelength range where silver halide photographic emulsions do not substantially absorb light and transmitting the light-absorbing electrons and / or light-absorbing energy to silver halide. There is. Therefore, the increase in the amount of light captured by the spectral sensitizer is advantageous for increasing the photographic sensitivity. Therefore, not only attempts have been made to develop a spectral sensitizer having a high light absorption coefficient, but also attempts have been made to increase the amount of light trapped by increasing the amount added to the silver halide emulsion.

However, the addition amount of the spectral sensitizer to the silver halide emulsion has an optimum addition region, which is usually less than the amount of the entire surface of the silver halide grain covered with the spectral sensitizer, and more than that. However, as mentioned above, a large desensitization is brought about. This is because T. H. Edited by James, `` The Theory of the Photographic
Process) 4th edition "Macmillan (New York) 197
7, P. 265-268.

(Problems to be Solved by the Invention) Therefore, attempts have been made to improve the addition method by which the addition amount of the spectral sensitizer can be increased and the preparation method of the silver halide grain emulsion.

For example, Thomas L Penner, PB Gilman, Jr., Photographik Science and Engineering (P
hot.Sci.Eng.), 20 (3), 97-106 (197)
6). As can be seen in Fig. 2, two kinds of spectral sensitizers having an appropriate electric potential are adsorbed in a layered manner on silver halide crystals in a large amount to increase the amount of light trapped by the spectral sensitizer and reduce the desensitization caused by the addition of a large amount. Attempts have been made to contain it. However, it has not been effective for a high-performance silver halide emulsion having high sensitivity to be provided as a photographic material. On the other hand,
Attempts have also been made to suppress the addition rate of silver halide grains by a spectral sensitizer to an optimum region where desensitization does not occur, increase the total addition amount, increase the light trapping amount, and improve the spectral sensitivity.

Here, the addition amount rate refers to the rate shown below.

For example, a method using a tabular silver halide having a large specific surface area similar to that used in the present invention is disclosed in JP-A-58-113,9.
No. 26 publication and the like. However, as described above, even if such tabular silver halide grains having a large specific surface area are used, the optimum addition amount ratio of the spectral sensitizer is other than halogens such as cubic, octahedral, tetrahedral and twin. Since it tends to be lower than silver halide grains, the addition amount cannot be increased unexpectedly, and the effect of increasing the spectral sensitization sensitivity as described above is not necessarily obtained. Improving the optimum addition amount of the spectral sensitizer with respect to the tabular silver halide grains is important from the viewpoint of utilizing the characteristics of the tabular silver halide grain emulsion having a good sensitivity / graininess ratio. For example, JP-A-60-11
As disclosed in JP-A-8,833, a certain kind of additive is used in combination to increase the optimum amount of addition, but the characteristics of tabular silver halide grains are utilized to obtain high sensitivity and sensitivity / granularity. In order to provide a light-sensitive material excellent in sex ratio and sharpness, there have been some aspects that have to be improved including stability over time. As a result of various studies, the present inventors have found a technique capable of greatly improving these points.

Accordingly, the present invention relates to a method for spectrally sensitizing a tabular silver halide grain emulsion, the most object of which is a very sensitive spectrally sensitized silver halide photographic emulsion, and a method for incorporating the same. An object is to provide a silver halide photographic light-sensitive material.

Another object of the present invention is to provide a method for producing an emulsion having high sensitivity, low fog and good graininess, and a silver halide photographic light-sensitive material without increasing the grain size of a tabular silver halide grain emulsion. It is to be.

A third object of the present invention is high sensitivity, less fog,
Another object of the present invention is to provide a method for producing a tabular silver halide grain emulsion having good graininess, which gives stability to the emulsion.

(Means for Solving the Problems) As a result of earnest studies, the present inventors have found that the above-mentioned objects are to a method for producing a photosensitive tabular silver halide grain emulsion having a grain diameter of 3 times or more the grain thickness. In this case, at least one kind of oxidizing agent consisting of hydrogen peroxide, peroxy acid salt, and ozone is used by the end of the chemical ripening step, and thereafter, when a reducing substance is added and no oxidizing agent is added, it is reduced. Achieved by spectral sensitization with a sensitizing amount of spectral sensitizer. Further, it was achieved by a silver halide photographic light-sensitive material characterized by having at least one layer containing such a tabular silver halide emulsion.

Next, the oxidizer used in the present invention will be described.

The hydrogen peroxide (water) used in the present invention may be used as an adduct thereof. For example, NaBO ₂ · H ₂ O ₂ · 3H ₂
O, 2NaCO ₃ · 3H ₂ O ₂ , Na ₄ P ₂ O ₇ · 2H ₂ O ₂ ,
_{2Na 2 SO 4 · H 2 O} 2 · 2H 2 O , and the like.

Examples of the peroxy acid salt used in the present invention include:
K ₂ S ₂ O ₈ , K ₂ C ₂ O ₆ , K ₄ P ₂ O ₈ , K ₂ [Ti (O ₂ )
C ₂ O _{4] · 3H 2 O, 4 · K} 2 SO 4 · Ti (O 2) OH · SO 4 · 2H 2 O, Na 3 _{[VO (O 2) (C 2} O 4) 2 · 6H 2 O ,
Peracetic acid etc. can be mentioned.

Among the oxidizing agents, hydrogen peroxide or its adduct or precursor is particularly preferable.

Most of these oxidizing agents are commercially available, and can be easily synthesized.

The addition amount of the oxidizing agent used in the present invention can be arbitrarily determined depending on the addition timing and the addition conditions, but is preferably 10 ⁻⁶ to 10 mol, and more preferably 10 ⁻⁴ to 1 mol per mol of silver halide.

The addition time may be any step (precipitation step, physical ripening step, water washing step, chemical ripening step) until the completion of the chemical ripening step. Preferred are precipitation, physical and chemical ripening steps.

Particularly preferred is the chemical ripening step (including immediately before the start of chemical ripening).

When an oxidizing agent is used in the present invention, metal salts (eg, tungsten salt (sodium tungstate, tungsten trioxide, etc.) vanadium salt (pervanadate, vanadium pentoxide, etc.) osmium salt (osmium tetroxide, etc.), molybdenum salt , Manganese salt, iron salt, copper salt, etc.} It can also be carried out in the presence of a catalyst such as selenium dioxide and an enzyme (eg, catalase). These catalysts may be added in advance before the addition of the oxidizing agent, or may be used simultaneously with or after the addition of the oxidizing agent. Usually 10 mg to 1
g / mol-Ag is used.

As the stabilizer of hydrogen peroxide used in the present invention, phosphoric acid, barbituric acid, urea, acetanilide, oxyquinoline, sodium pyrophosphate, sodium stannate and the like can be used.

The oxidizing agent may be added after being dissolved in water or an organic solvent soluble in water (for example, alcohols, ethers, glycols, ketones, esters, amides, etc.).

Further, the reducing substance used for deactivating the excess oxidizing agent that can be used in the present invention is hydrogen peroxide, a peroxy acid salt or a compound capable of reducing ozone. Specifically preferred are sulfinic acid salts (benzenesulfinic acid and derivatives thereof), di- and trihydroxybenzenes (resorcin, catechol and derivatives thereof), chromanes (chroman, spirochroman, etc.),
Hydrazine and hydrazides (N-formyl p-methylhydrazine etc.), p-phenylenediamines (p-
Phenylenediamine, etc.), aldehydes (glutaraldehyde bisulfite, etc.), aminophenols (N-methylaminophenol, etc.), enediols (ascorbic acid, etc.), oximes (glyoxime, etc.), reducing sugars (glucose) , Satsukarose, etc.),
Examples include phenidones and sulfites.

Particularly preferred compounds are sulfinic acids, or trihydroxybenzenes, enediols, oximes,
It is a reducing sugar.

The reducing substance is preferably added after addition of the oxidizing agent used, before or after addition of the spectral sensitizer, or at the same time, but preferably at the chemical ripening step and at the end of the chemical ripening.

The amount of the reducing substance added varies depending on the amount of the oxidizing agent used and the degree of deactivation thereof, but is usually equimolar to equimolar or more to the oxidizing agent, preferably equimolar to 10 times the molar amount. Is used.

If it is used in a molar amount of 10 times or more, problems such as fog tend to occur over time, which is not preferable.

The stability of the emulsion can be increased by using this reducing substance.

If an excessive amount of oxidizing agent remains, the sensitivity of the emulsion will be significantly reduced due to the oxidizing action when the emulsion is stored in a refrigerator for a long time after the completion of chemical ripening.

Further, when the emulsion is coated, the sensitivity is lowered when the emulsion is dissolved and left for a long time. Also, during chemical ripening, sensitivity and fogging fluctuate greatly.

By adding this reducing substance after adding the oxidizing agent, it was possible to substantially eliminate the above-mentioned fluctuations in sensitivity and fog.

It has been conventionally known that an oxidizing agent is used when preparing a silver halide emulsion. For example, in a heat-developable photosensitive material, it is known to be used in a process called halogenation in which a silver halide is prepared from a carboxylic acid silver salt using a halogen-releasing oxidizing agent. It is also known that an oxidizing agent is added to a usual silver halide emulsion or the above-mentioned heat-developable photosensitive material to prevent fogging. For example, Japanese Patent Publication Sho 53
No. 40484, No. 54-35488, JP-A No. 52-
No. 4821, No. 49-10724, No. 49-4571.
No. 8 specification. However, the purpose and effect of using these oxidizing agents for ordinary spherical silver halide grains and the purpose and effect of using them in the tabular silver halide emulsion as in the present invention are quite different. When a sulfur-containing silver halide solvent is used in the formation of silver halide grains, an oxidizing agent is used after grain formation to deactivate the solvent or reduce its action, and to prevent the solvent from exerting an undesired action on the next step. It is also known to add an oxidizing agent in the removed form for the purpose of facilitating adjustment of chemical sensitization, spectral sensitization, etc. (JP-A-60-136,736, Japanese Patent Application No. 59-122,981).

The oxidizing agent of the present invention is also excellent as a deactivator when a sulfur-containing silver halide solvent is used during the formation of silver halide grains, but the objects and effects of the present invention are distinctly different. .

That is, the sensitizing effect and the like of the present invention occur not only in ordinary spherical particles but in tabular grains.

Next, the tabular silver halide grains used in the present invention will be described.

The tabular silver halide grain of the present invention preferably has a diameter / thickness ratio of 3 or more, more preferably 5 or more and 50 or less, and particularly preferably 5 or more and 20 or less.

Here, the diameter of a silver halide grain means the diameter of a circle having an area equal to the projected area of the grain. In the present invention, the tabular silver halide grains have a diameter of 0.3 to 5.0 µ, preferably 0.5 to 3.0 µ.

The thickness is 0.4 μm or less, preferably 0.3 μm or less, and more preferably 0.2 μm or less.

In general, tabular silver halide grains are tabular having two parallel planes, and therefore "thickness" in the present invention means the distance between two parallel planes constituting tabular silver halide grains. It is represented by.

The tabular silver halide grains may have any halogen composition such as silver bromide, silver iodobromide, silver iodochlorobromide, silver chlorobromide and silver chloride. Of these, silver bromide and silver iodobromide are preferable, and silver iodobromide having a silver iodide content of 3 is particularly preferable.
It is preferably 0 mol% or less.

The tabular silver halide grains can be produced by appropriately combining methods known in the art.

For example, tabular silver halide emulsions are available from Cagnac
And Chateau, "Progress in the morphology of silver bromide crystals during physical ripening (Evolution of the Morphol G-Silver Bromide Crystals-Duaring Physical Reining") Science E・ Industrie Photographie, Volume 33
No. 2 (1962), pp. 121-125, Dub
ffin) "Photographic emulsion chemistry", Focal Press, New York, 1966,
p. 66-p. 72, A. P. H. Trivel
i), W. F. Smith Photograph Journal, 80, 285 (19)
40 years) and Japanese Patent Laid-Open No. 58-12.
7,921, JP-A-58-113,927, JP-A-58
It can be easily prepared by referring to the method described in -113,928.

For example, a seed crystal in which tabular grains are present at 40% or more by weight is formed in an atmosphere of a relatively low pBr value of pBr 1.3 or less, and a seed crystal is added while maintaining the same pBr value and simultaneously adding a silver and halogen solution. Obtained by growing crystals.

During this grain growth process, it is desirable to add a silver and halogen solution so that new crystal nuclei are not generated.

The size of tabular silver halide grains can be adjusted by controlling the temperature, selecting the type and amount of solvent, and controlling the addition rate of silver salt and halide used during grain growth.

By using a silver halide solvent during the production of the tabular silver halide grains of the present invention, the grain size of the grain (diameter / thickness ratio, etc.), grain size distribution and grain growth rate can be controlled.

For example, as the amount of solvent used increases, the particle size distribution can be made monodisperse and the growth rate can be increased. On the other hand, there is also a tendency that the particle thickness increases with the amount of solvent used.

When the tabular silver halide grains of the present invention are produced, the addition rate, amount and concentration of silver salt solution (eg AgNO ₃ aqueous solution) and halide solution (eg KBr aqueous solution) which are added to accelerate grain growth are increased. The method is preferably used.

Regarding these methods, for example, British Patent No. 1,335,
925, US Pat. Nos. 3,672,900 and 3,
650,757, 4,242,445, JP-A-55-142329, JP-A-55-158124, and JP-A-5-158124.
8-113927, 58-113928, 58
Reference can be made to the descriptions in Nos. 111,934 and 58-111936.

The tabular silver halide grains of the present invention have been chemically sensitized.

As the chemical sensitization method, a gold sensitization method using a so-called gold compound (for example, US Pat. Nos. 2,448,060 and 3,32) is used.
No. 0,069) or a sensitization method using a metal such as iridium, platinum, rhodium or palladium (for example, US Pat. No. 2,4,4).
48,060, 2,566,245, 2,56
No. 6,263) or a sulfur sensitizing method using a sulfur-containing compound (for example, sulfur-containing sensitizers such as thiosulfates, thioureas, mercapto compounds, rhodanins, etc. can be mentioned. First 1,574,944
No. 2,410,689, No. 2,278,94
No. 7, No. 2,728,668, No. 3,656,9
55, U.S. Pat. No. 2,222,264), or reduction sensitization methods using tin salts, polyamines and the like (for example, U.S. Pat. Nos. 2,487,850, 2,518,698, and 2,521). No. 925) or a combination of two or more thereof.

In particular, the tabular silver halide grains of the present invention are preferably combined with gold sensitization and sulfur sensitization.

When a sensitization method using a gold complex salt is carried out, it is preferable to use a gold ligand such as thiosulfate, thiocyanate or thioether as an auxiliary agent, and particularly thiocyanate such as potassium thiocyanate. Is preferred.

The addition amount of the sensitizer varies depending on the type of silver halide emulsion, but the sulfur sensitizer is usually 1 × 10 ⁻⁷ to
1 × 10 ^-4 mol / mol Ag, noble metal sensitizer is 1 × 10 ^-7
˜1 × 10 ⁻⁴ mol / mol Ag is preferred.

In the layer containing the tabular silver halide grains of the present invention,
It is preferable that the tabular grains are present in an amount of 40% or more, and particularly 60% or more by weight based on the total silver halide grains in the layer.

The thickness of the layer containing tabular silver halide grains is 0.3-
It is preferably 5.0 μ, particularly preferably 0.5 to 3.0 μ.

Also, the coating amount of tabular silver halide grains (for one side)
Is preferably 0.5 to 15 g / m ² .

The emulsion layer of the silver halide photographic light-sensitive material of the present invention may contain ordinary silver halide grains in addition to the tabular silver halide grains.

The usual photographic emulsions used in combination with the present invention are
Chimie et Physique Photog by P. Glafkides
raphique) "(Paul Montel, 19)
67), GF Duffin, "Photographic Emergy Chemistry (Photogr
aphic Emulsion Chemistry ”(The Focal Press, 1966), VL Zelikman et al.“ Making and Coating Photographics ” Emulsion) "
(Published by The Focal Press, 196
4 years) and the like.

The silver halide may be any of silver bromide, silver iodobromide, silver iodochlorobromide, silver chlorobromide, silver chloride and the like.

In the process of silver halide grain formation or physical ripening,
Cadmium salt, zinc salt, lead salt, thallium salt, iridium salt or its complex salt, rhodium salt or its complex salt, iron salt or iron complex salt may coexist. Further, if necessary, chemical sensitization can be carried out in the same manner as tabular silver halide grains.

The photographic emulsion containing tabular grains of the present invention may contain various compounds for the purpose of preventing fog during production process of the light-sensitive material, storage or photographic processing or stabilizing photographic performance. . That is, azoles such as benzothiazolium salts, nitroindazoles, nitrobenzimidazoles, chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, aminotriazoles. , Benzotriazoles, nitrobenzotriazoles, mercaptotetrazoles (especially 1
-Phenyl-5-mercaptotetrazole) and the like; mercaptopyrimidines; mercaptotriazines; thioketo compounds such as oxazolinethione; azaindenes such as triazaindenes, tetraazaindenes (especially 4-hydroxy-substituted (1,3 , 3a,
7) Tetrazaindenes), pentaazaindenes, etc .; Add many compounds known as antifoggants or stabilizers such as benzenethiosulphonic acid, benzenesulphonic acid, benzenesulphonic acid amide, etc. You can For example, those described in U.S. Pat. Nos. 3,954,474, 3,982,947 and JP-B-52-28,660 can be used.

Examples of the spectral sensitizer used in the present invention include methine dyes. Methine dyes include polymethine dyes including cyanine dyes, merocyanine dyes, complexus cyanine dyes, complex merocyanine dyes, oxonol dyes, styryl dyes, hemicyanine dyes, hemioxylinol dyes, merostyryl dyes, and streptocyanins.

For these methine dyes, any of the nuclei normally used for cyanine dyes as a basic heterocyclic nucleus can be applied. That is, pyrrolidine nucleus, 3H-indole nucleus, oxazolidine nucleus, oxazoline nucleus, oxazole nucleus, benzoxazole nucleus, naphthoxazole nucleus, thiazolidine nucleus, thiazoline nucleus, thiazole nucleus, benzothiazole nucleus, naphthothiazole nucleus, selenazolidine nucleus, selenazoline nucleus, Selenazole nucleus, benzoselenazole nucleus, naphthoselenazole nucleus, imidazoline nucleus, imidazole nucleus,
Benzimidazole nucleus, naphthimidazole nucleus, tetrazole nucleus, tellurazole nucleus, benzotelrazole nucleus, naphthotellurazole nucleus, imidazo [4,5-b] quinoxazaline nucleus, dihydronaphthothiazole nucleus, dihydronaphthoselenazole nucleus, pyridine nucleus, quinoline Nuclear etc. can be applied. These nuclei may have a substituent on a carbon atom.

As the nuclei having an acidic ketomethylene structure, any of the nuclei usually used for merocyanine dyes can be applied to the methine dyes. For example, as such a nucleus, a pyrazolin-5-one nucleus, a thiohydantoin nucleus, a 2-thiooxazolidine-2,4-dione nucleus, a thiobarbituric acid nucleus, a barbituric acid nucleus, an indan-1,3-dione nucleus,
Examples thereof include cyclohexane-1,3-dione nucleus, 1,3-dioxane-4,6-dione nucleus, pyrazoline-3,5-dione nucleus, pentane-2,4-dione nucleus and the like.

Examples of the literature describing the methine dye used in the present invention include:
FM Hamer, "The Chemistry of Heterocycle Compounds
terocyclic Compounds, Vol. 18, The Cyanine, Soybean and Rerated Compounds
Dyes and Related Compounds) "(A. Wise Burger
Weissberger, edited by InterScience-New York-1964, by DM Sturmer, "The Cyanine Dyes and Related Compou Vol.
nds) ”(A. Weissberger, EC Taylor
Taylor ed., Jiyoung Wheelie-New York-1977
Annual), Research Disclosure (RESEARCH DISC
LOSURE) Volume 176, No. 17643, p. 23-24 (1
978), German Patent 929,080, US Patent 2,
231,658, 2,493,748, 2,5
03,776, 2,519,001, 2,91
No. 2,329, No. 3,656,959, No. 3,67
2,897, 3,694,217, 4,02
5,349, 4,046,572, British Patent 1,
No. 242,588, Japanese Examined Patent Publication No. 44-14030, No. 52
-24844, British Patent 584,609, 1,1
77,429, JP-A-48-85130, 49-
No. 99620, No. 49-114420, No. 52-10.
8115, US Pat. Nos. 2,274,782 and 2,5.
33,472, 2,956,879, 3,14
8,187, 3,177,078, 3,24
7,127, 3,540,887, 3,57
5,704, 3,653,905, 3,71
8,472, 4,071,312, 4,07
No. 0,352 and the like can be mentioned.

These spectral sensitizers may be used alone or in combination, and the combination of spectral sensitizers is often used especially for the purpose of supersensitization.

Along with the spectral sensitizer, a dye having no spectral sensitizing effect or a substance which does not substantially absorb visible light and exhibits supersensitization may be contained in the emulsion. For example, aminostilbene compounds substituted with a titanium-containing heterocyclic group (for example, US Pat. Nos. 2,933,390 and 3,3,390).
635,721), an aromatic organic acid formaldehyde condensate (for example, US Pat. No. 3,743,51).
No. 0), cadmium salt, azaindene compound and the like. US Patent 3,615,613
No. 3,615,641, No. 3,617,295
No. 3,635,721, the combination is particularly useful.

Among the sensitizing dyes used in the present invention, more preferred methine dyes are cyanine dyes, merocyanine dyes, rhodacyanine dyes, and further, for the examples of particularly preferred dyes used in the present invention, the following general formula [DI], [D-II],
And the dyes represented by [D-III], and the most preferable dye is a cyanine dye represented by the general formula [DI].

General formula [DI] Q ¹ and Q ² may be the same or different and each is oxazoline, oxazole, benzoxazole, naphthoxazole (for example, naphtho [2,1-d] oxazole, naphtho [1,2-d] oxazole. , Naphtho [2,3-d] oxazole), thiazoline, thiazole, benzothiazole, naphthothiazoles (for example, naphtho [1,2-d] thiazole, naphtho [2,1-d]).
Thiazole, naphtho [2,3-d] thiazole), dihydronaphthothiazole (eg, 8,9-dihydronaphtho [1,2-d] thiazole, etc.), selenazoline, selenazole, benzoselenazole, naphthoselenazole (eg, naphtho [ 1,2-d] selenazole, naphtho [2,2
1-d] selenazole), 3H-indoles (eg, 3,3-dimethyl-3H-indole, etc.), benzindoles, imidazoline, imidazole, benzimidazole, naphthoimidazoles (eg, naphtho [1,2]
-D] imidazole, naphtho [2,3-d] imidazole), pyridine, quinoline, imidazo [4,5-b] quinoxaline, pyrrolidineterrazole, benzoterrazole, naphthoterrazole (for example, naphtho [1,2-
d) tellurazole, naphtho [2,1-d] telrazole) and the like represent an atomic group necessary for forming a ring nucleus derived from a basic heterocyclic compound usually used for cyanine dyes. The above nuclei may have one or more various substituents present on the ring. Such substituents include hydroxy, halogen (eg fluorine, chlorine, bromine), lower alkyl groups or substituted alkyl groups (eg methyl, ethyl, propyl, isopropyl, butyl, cyclohexyl, octyl, decyl, 2-hydroxyethyl). , Carboxymethyl, ethoxycarbonylmethyl, trifluoromethyl, methoxymethyl, benzyl, phenethyl and the like), an aryl group or a substituted aryl group (for example, phenyl, 1-naphthyl, 2-naphthyl, tolyl, anisyl, 4-chlorophenyl, 2-thienyl). , 2-frills,
2-pyridyl, 4-pyridyl, etc.), lower alkoxy group or substituted alkoxy group (eg, methoxy, ethoxy, isopropoxy, decyloxy, 2-methoxyethoxy, etc.), aryloxy group (eg, phenoxy, 1-naphthoxy, 4-methoxyphenyl). Enoxy, 4-methylphenoxy, 3-chlorophenoxy etc.), lower alkylthio group (eg methylthio, ethylthio, butylthio, decylthio etc.), arylthio group (eg phenylthio, p-
Tolylthio, p-anisylthio, 2-naphthylthio, etc.), methylenedioxy group, cyano group, amino group or substituted amino group (eg, anilino, dimethylamino, diethylamino, morpholino, monomethylamino, bis (hydroxyethyl) amino, acetamide, benzoyl) Amide, methylsulfonylamino, etc.), carboxy group, alkoxycarbonyl group (eg, methoxycarbonyl, ethoxycarbonyl, etc.), acyl group (eg, acetyl, benzoyl, propionyl, methylsulfinyl, methylsulfonyl, etc.) and the like.

G ¹ and G ² may be the same or different and each represents an alkyl group, an aryl group or an alkenyl group, which may be unsubstituted or substituted. For example, methyl, ethyl, propyl, isopropyl, butyl, octyl, decyl, octadecyl, methoxyethyl, 2-ethoxyethyl, 2-hydroxyethyl, carboxymethyl, 2-
Carboxyethyl, 3-carboxypropyl, 2-sulfoethyl, 3-sulfopropyl, 3-sulfobutyl, 4
-Sulfobutyl, 2-sulfatoethyl, 2-phosphonoethyl, chlorophenyl, allyl, 1-butenyl, 2,
2,2-trifluoroethyl, 2,2,3,3-tetrafluoropropyl, phenethyl, 4-sulfophenethyl, 2-chloropropyl, 2-hydroxy-3-sulfopropyl, ethoxycarbonylmethyl and the like can be mentioned.

G ³ is hydrogen or fluorine, and when n ² is not 0, it also represents an alkyl group or a substituted alkyl group (for example, methyl, ethyl, methoxyethyl, etc.), and an alkylene bridge with G ¹ to form a 5- or 6-membered ring. May be formed.

G ⁴ and G ⁵ are hydrogen, an unsubstituted or substituted lower alkyl group (eg, methyl, ethyl, propyl, methoxyethyl, benzyl, phenethyl, etc.), an aryl group (eg, phenyl,
Anisyl, tolyl, etc.), n ¹ and n ³ are 0 or 1, and n ² is 0, 1, 2 or 3. Y ¹ is a cationic group, W ¹ is an anionic group, and k ¹ and k ²
Is 0 or 1 and these depend on the presence or absence of ionic substituents. In addition, G ³ and G ⁵ , G ⁴ and G ⁴ (when n ² is 2 or 3), G ⁵ and G ⁵ (when n ² is 2 or 3), or G ² and G ⁵ are in an alkylene bridged L ring. It is also possible to represent an atom necessary for completing a 5- or 6-membered ring which may contain an oxygen atom or a nitrogen atom.

General formula [D-II] Q ³ has the same meaning as Q ¹ or Q ^{2 in} the formula [DI], and G ¹⁰ represents G ¹ or G ^{2 in the} formula [DI].
And G ¹¹ and G ¹² are hydrogen, a lower unsubstituted or substituted alkyl group (for example, methyl, ethyl, propyl, methoxyethyl, benzyl, phenethyl, 2-hydroxyethyl, 2-carboxyethyl, etc.). ), An aryl group (eg, phenyl, naphthyl, 2-carboxyphenyl, tolyl, 4-chlorophenyl, etc.),
Represents a halogen atom (eg fluorine, chlorine). G ¹⁰ ,
Any two selected from G ¹¹ and G ¹² can represent the elements necessary to complete the alkylene bridge.

G ¹³ and G ¹⁴ may be the same or different and each represents an electron-withdrawing group. For example, cyano group, alkyl or aryl sulfonyl group (for example, methyl sulfonyl, phenyl sulfonyl, tolyl sulfonyl, octyl sulfonyl group), carboxy group, alkyl or aryl carbonyl group (for example, acetyl, propionyl, decanoyl,
Benzoyl, tolylcarbonyl, 2-thienylcarbonyl, etc.), a 5- or 6-membered nitrogen-containing heterocyclic group (for example, 2-thiazolyl, 2-benzothiazolyl, 2-benzimidazolyl,
2-pyridyl, 2-benzoselenazolyl, etc.) and the like. In addition, G ¹³ and G ¹⁴ are combined to form 2,4-oxazolidinedione (for example, 3-ethyl-2,4-oxazolidinedione, etc.) and 2,4-thiazolidinedione (for example, 3-butyl-2,4-thiazolidinedione). Etc.), 2-thio-2,4-oxazolidinedione (for example, 3-phenyl-2-thio-2,4-oxazolidinedione, etc.), rhodanins (for example, 3-ethylrhodamine, 3-carboxymethylrhodamine, 3). -(2-Sulfoethyl) rhodanine, 3-phenyl rhodanine, 3-furfuryl rhodanine, 3- (3-dimethylaminopropyl) rhodanine, 3- (2-ethoxyethyl) rhodanine, 3-benzyl rhodanine, etc.) , Hydantoin (eg 1,3-diethylhydantoin etc.), 2-thiohydantoin (eg 1,3-diethyl-2) Thiohydantoin, 1-ethyl-3-phenyl-2-thiohydantoin, 1- (2-
Hydroxyethyl) -3-phenyl-2-thiohydantoin, 1- [2- (2-hydroxyethoxy) ethyl]
-3- (2-pyridyl) -2-thiohydantoin, 1-
N- (2-hydroxyethyl) aminocarbonylmethyl-3-phenyl-2-thiohydantoin, etc., 2-pyrazolin-5-ones (for example, 3-methyl-1-phenyl-2-pyrazolin-5-one, 3 -Methyl-1- (4-
Carboxybutyl) -2-pyrazolin-5-one, 3-
Methyl-1- (4-sulfophenyl) -2-pyrazolin-5-one and the like), 2-isoxazolin-5-ones (for example, 3-phenyl-2-isoxazolin-5-one and the like), 3,5- Pyrazolidinedione (eg 1,2-
Diphenyl-3,5-pyrazolidinedione etc.), 1,3
-Indandione, 1,3-dioxane-4,6-dione, 1,3-cyclohexanedione, 2-thioselenazolidine-2,4-diones (for example, 3-ethyl-2-
Thioselenazolidine-2,4-dione, 3-phenyl-
2-thioselenazolidine-2,4-dione), barbituric acid (for example, 1,3-diethylbarbituric acid, etc.),
2-thiobarbituric acid (eg 1,3-diethylbarbituric acid, 1,3-bis (2-methoxyethyl) -2
-Thiobarbituric acid, etc.) and the like, which can represent a group of atoms necessary for completing a cyclic acidic nucleus normally used for a merocyanine dye such as oxonol dye, n ⁴
Is 0 or 1 and n ⁵ represents 0, 1, 2 or 3.

In the spectral sensitizer represented by the general formula [D-II],
More preferably, G ¹³ and G ¹⁴ are combined to form 2-thiooxazolidine-2,4-diones, rhodanines, 2-
Thiohydantoins, 2-thioselenazolidine-2,4
A case where it represents a dione, and n ⁵ is 1, 2 or 3
Is represented.

General formula [D-III] Q ⁴ and Q ⁶ represent the same meaning as either Q ¹ or Q ² of the formula [DI], and G ²¹ and G ²² represent G of the formula [D-II].
Synonymous with either ¹¹ or G ¹² . G ²³ and G
²⁴ has the same meaning as G ⁴ or G ⁵ in the above formula [DI], and G ²⁵ and G ²⁶ have the same meaning as either G ¹ or G ^{2 in} the above formula [DI]. G ⁵ represents an element necessary for completing the nitrogen-containing 5-membered ring. Examples of the nitrogen-containing 5-membered ring include -oxooxazolidine, 4-oxothiazolidine, 4-oxoimidazolidine and the like. G
²⁵ and G ²⁶ have the same meaning as G ¹ or G ² in the above formula [DI], and G ²⁷ represents an alkyl group, an aryl group or an alkenyl group, which may be unsubstituted or substituted. For example, methyl, ethyl, propyl, isopropyl, butyl, octyl, decyl, octadecyl, methoxyethyl, 2-ethoxyethyl, 2-hydroxyethyl, carboxyethyl, 2-carboxyethyl, 3-carboxypropyl, 2-sulfoethyl, 3- Sulfopropyl, 4-sulfobutyl, 2-cyanoethyl, 2-carbamoylethyl, 2,2,2-trifluoroethyl, allyl, phenethyl, 4-sulfophenyl, 2-ethoxycarbonylmethyl, 2-pyridyl, 2-furyl, furfuryl, Examples thereof include phenyl, 4-carboxyphenyl, tolyl, anisyl and the like. n ⁶ and n ⁹ are 0 or 1, n ⁷ is 0, 1 or 2 and n ⁸ is 0, 1 or 2. Y ² is a cation group, W ² is an anion group, and k ⁴
And k ³ are 0 or 1, depending on the presence or absence of ionic substituents.

Next, typical compounds of the spectral sensitizer used in the present invention are shown below.

D-1 D-2 D-3 D-4 D-5 D-6 D-7 D-8 D-9 D-10 D-11 D-12 D-13 D-14 D-15 D-16 D-17 D-18 D-19 D-20 D-21 D-22 D-23 D-24 D-25 D-26 D-27 D-28 D-29 D-30 D-31 D-32 To incorporate the spectral sensitizers used in the present invention in the silver halide emulsion of the present invention, they may be dispersed directly in the emulsion, or water, methanol, ethanol,
It may be added to the emulsion by dissolving it in a solvent such as propanol, methyl cellosolve, 2,2,3,3-tetrafluoropropanol or the like alone or in a mixed solvent. In addition, Japanese public examination 4
4-23,389, JP-B-44-27,555, JP-B-57-22,089 and the like, an acid or a base is allowed to coexist to form an aqueous solution, or US Pat.
As described in US Pat. No. 4,006,025, an aqueous solution or colloidal dispersion prepared by coexisting a surfactant such as sodium dodecylbenzenesulfonate may be added to the emulsion. Alternatively, the emulsion may be dissolved in a solvent which is substantially immiscible with water such as phenoxyethanol, and then dispersed in water or a hydrophilic colloid to be added to the emulsion. JP-A-5
As described in 3-102,733 and JP-A-58-105,141, it may be directly dispersed in a hydrophilic colloid, and the dispersion may be added to the emulsion.

When these compounds are added to the emulsion, a mixture may be added or they may be added separately.
The time of addition to the emulsion may be any step (eg, silver halide grain forming step, physical ripening step, chemical ripening step, grain precipitation step, post-coating step after chemical ripening, etc.) before coating the emulsion on an appropriate support. ) May be used, but it is preferable after using the above-mentioned oxidizing agent.

The addition amount of the spectral sensitizer used in the present invention (the amount that causes desensitization when an oxidizing agent is not added) is 10
^-5 to 10 ^-2 mol / silver mol can be used, but in order to bring out the full advantage of the present invention, an amount corresponding to an addition amount ratio of 50% or more is preferable. Even more preferably 60 to 30
This is an amount corresponding to a 0% addition rate.

In other words, at least 0.18 log E or more, more preferably, when no oxidizing agent is added,
The advantages and effects of the present invention are remarkable when the amount of the spectral sensitizer added is such that the intrinsic sensitivity is reduced to 0.15 log E to 1.0 log E.

Here, when measuring the decrease in intrinsic sensitivity, the decrease in intrinsic sensitivity can be determined by performing development for 4 minutes at 20 ° C. after normal development, for example.

Various color couplers may be used in the silver halide emulsion of the present invention. Specific examples thereof include Research Disclosure (RD) No. 17643, VII-C to G mentioned above.
Are described in the patents listed in. As the dye-forming coupler, a coupler which gives the three primary colors of the subtractive method (that is, yellow, magenta and cyan) by color development is important, and specific examples of the diffusion resistant 4-equivalent or 2-equivalent coupler are RD17643, VII- In addition to the couplers described in the patents described in C and D, the following can be preferably used in the present invention.

A typical example of the yellow coupler that can be used in the present invention is a hydrophobic acylacetamide coupler having a ballast group. A specific example is US Pat. No. 2,
No. 407,210, No. 2,875,057 and No. 3,265,506. In the present invention, it is preferable to use a two-equivalent yellow coupler, and US Pat. Nos. 3,408,194 and 3,447,928 are preferred.
No. 3,933,501 and No. 4,022.
No. 620 and other yellow couplers of oxygen atom elimination type or Japanese Patent Publication No. 58-10739, U.S. Pat. Nos. 4,401,752, 4,326,024, R
D18053 (April 1979), British Patent No. 1,42
No. 5,020, West German Application Publication No. 2,219,917,
Typical examples thereof include nitrogen atom releasing yellow couplers described in Nos. 2,261,361, 2,329,587 and 2,433,812. The α-pivaloyl acetanilide type coupler is excellent in the fastness of the color forming dye, especially the light fastness, while
The benzoylacetanilide coupler provides high color density.

Examples of magenta couplers that can be used in the present invention include hydrophobic indazolone or cyanoacetyl, preferably 5-pyrazolone and piazoloazole couplers having a ballast group. The 5-pyrazolone-based coupler is preferably a coupler in which the 3-position is substituted with an arylamino group or an acylamino group, from the viewpoint of the hue and color density of the color forming dye, and a representative example thereof is US Pat.
311,082, 2,343,703, 2,600,788, 2,908,573, 3,062,653, 3,152,896 and No. 3,936,015.
As the leaving group of the 2-equivalent 5-pyrazolone-based coupler, the nitrogen atom leaving group described in US Pat. No. 4,310,619 or the arylthio group described in US Pat. No. 4,351,897 is preferable. European Patent No. 73,6
The 5-pyrazolone-based coupler having a ballast group described in No. 36 provides high color density. Pyrazoloazole couplers include pyrazolobenzimidazoles described in U.S. Pat. No. 3,369,879, preferably pyrazolo [5,5] described in U.S. Pat. No. 3,725,067.
1-c] [1,2,4] triazoles, Research Disclosure 24220 (June 1984) and pyrazolotetrazoles and Research Disclosure 24230 described in JP-A-60-33552.
(June 1984) and the pyrazolopyrazoles described in JP-A-60-43659. The imidazo [1,2-, described in U.S. Pat. No. 4,500,630, in view of low yellow sub-absorption of a coloring dye and light fastness.
b] Pyrazoles are preferred, EP 119,86
0A pyrazolo [1,5-b] [1,2,4]
Triazole is especially preferred.

The cyan couplers usable in the present invention are hydrophobic and diffusion resistant naphthol and phenol couplers, and the naphthol couplers described in U.S. Pat. No. 2,474,293, preferably U.S. Pat. 052
No. 212, No. 4,146, 396, No. 4,22
Typical examples are the oxygen atom desorption type two-equivalent naphthol couplers described in JP-A-8,233 and JP-A-4,296,200. Further, specific examples of the phenol-based coupler are described in US Pat. Nos. 2,369,929 and 2,8.
01,171, 2,772,162, 2,
No. 895,826.

A cyan coupler which is fast against humidity and temperature is preferably used in the present invention, and typical examples thereof include an alkyl group having an ethyl group or higher at the meta-position of the phenol nucleus described in US Pat. No. 3,772,002. A phenolic cyan coupler having a group, US Pat. No. 2,722,162,
No. 3,758,308, No. 4,126,396
No. 4,334,011, No. 4,327,17
No. 3, West German Patent Publication No. 3,329,729, European Patent No. 121,365, and the like, and 2,5-diacylamino-substituted phenol-based couplers and US Pat. Nos. 3,446,622 and 4 , 333, 999, 4,451, 559 and 4,427, 767.
And the like, which have a phenylureido group at the 2-position and an acylamino group at the 5-position.

In order to correct the unnecessary absorption of the chromophore, it is preferable to mask the color sensitive material for photographing with a colored coupler. Yellow colored magenta couplers described in U.S. Pat. No. 4,163,670 and Japanese Patent Publication No. 57-39413 or U.S. Pat. No. 4,004,929.
No. 4,138,258 and British Patent No. 1,1.
Typical examples are magenta colored cyan couplers described in JP-A No. 46,368. Other colored couplers are described in RD17643, paragraphs VII-G above.

The graininess can be improved by using a coupler in which the color forming dye has an appropriate diffusibility. Such couplers are
U.S. Pat. No. 4,366,237 and British Patent No. 2,
Specific examples of magenta couplers are disclosed in 125,570, European Patent No. 96,570 and West German Patent Application Publication No. 3,2.
No. 34,533 describes specific examples of yellow, magenta or cyan couplers.

The dye-forming coupler and the above-mentioned special coupler may form a dimer or higher polymer. Typical examples of polymerized dye forming couplers are found in US Pat. No. 3,451,82.
0 and 4,080,211. Specific examples of polymerized magenta couplers are described in British Patent No. 2,102,173 and US Patent No. 4,367,
282.

Couplers that release a photographically useful residue upon coupling are also preferably used in the present invention. The DIR coupler releasing the development inhibitor is RD17643, VI described above.
The couplers of the patents described in paragraphs I-F are useful. A preferred combination with the present invention is JP-A-57-1.
Developer deactivation type represented by No. 51944; U.S. Pat. No. 4,248,962 and JP-A-57-154234.
Timing type represented by the Japanese Patent No. 59-39653
No. 57-151944, JP-A No. 58-217932 and JP-A Nos.
Developer inactivating DIR couplers described in Japanese Patent Application Nos. 59-75474, 59-82214, 59-82214 and 59-90438, and Japanese Patent Application No. 59-75438.
It is a reactive DIR coupler described in JP-A-39653 and the like.

The light-sensitive material produced by using the present invention may contain a hydroquinone derivative, an aminophenol derivative, a gallic acid derivative, an ascorbic acid derivative, etc. as a color antifoggant. The hydrophilic colloid layer may contain an ultraviolet absorber. For example, benzotriazole compounds substituted with an aryl group (for example, those described in US Pat. No. 3,533,794) and 4-thiazolidone compounds (for example, US Pat. Nos. 3,314,794 and 3,352,681) Those described), benzophenone compounds (for example, those described in JP-A-46-2784), cinnamic acid ester compounds (for example, US Pat.
Nos. 05,805 and 3,707,375), butadiene compounds (for example, US Pat. No. 4,045,
229) or a benzooxide compound (for example, those described in US Pat. No. 3,700,455). Furthermore, US Pat.
The materials described in JP-A-54-48535 and 499,762 can also be used. UV absorbing couplers (eg α-naphthol cyan dye forming couplers)
Alternatively, an ultraviolet absorbing polymer or the like may be used. These UV absorbers may be mordanted in a specific layer.

In carrying out the present invention, the following known anti-fading agents may be used in combination, and the color image stabilizers used in the present invention may be used alone or in combination of two or more kinds. Known anti-fading agents include hydroquinone derivatives, gallic acid derivatives, p-alkoxyphenols, p-oxyphenol derivatives and bisphenols.

The compounds used in the silver halide emulsion and the photographic light-sensitive material used in the present invention include, in addition to those mentioned above, a desensitizer, a whitening agent, a high-boiling organic solvent (coupler solvent), an anti-staining agent, an absorber (dye). ), A binder, a hardener, a coating aid (surfactant), a plasticizer, a lubricant, an antistatic agent, a development accelerator and the like. The above-mentioned additives and these additives can be found in RESEARCH DISCLOSOR.
E) Magazine Volume 176, No. 17643 (December 1978)
The compounds described in the paragraphs I to XVI (p.22 to p.28) of (Month) can be used.

The surface of the photographic material of the present invention is a synthetic polymer material such as gelatin or a water-soluble polyvinyl compound or acrylamide polymer or a natural polymer material (for example, US Pat. Nos. 3,142,568 and 3,193,386). No. 3,062,674) as a main component.

In the surface protective layer, in addition to gelatin or other polymer substance,
Surfactants / antistatic agents, matting agents, slip agents, curing agents, thickeners and the like can be contained.

The photographic material of the present invention may further include an intermediate layer, if necessary.
It may have a filter layer, an anti-halation layer and the like.

In the photographic light-sensitive material of the present invention, the photographic emulsion layer and other layers are coated on a flexible support such as a plastic film, paper or cloth usually used for photographic light-sensitive materials. What is useful as the flexible support is a film made of a semi-synthetic or synthetic polymer such as cellulose nitrate, cellulose acetate, cellulose acetate, cellulose acetate, polystyrene, polyvinyl chloride, polyethylene terephthalate (PET), or polycarbonate, or a baryter layer or Examples include paper coated or laminated with an α-olefin polymer (eg, polyethylene, polypropylene, ethylene / butene copolymer).
The support may be colored with a dye or pigment. It may be black for the purpose of shading. The surface of these supports is generally subbed to improve adhesion with photographic emulsion layers and the like. The surface of the support may be subjected to corona discharge, ultraviolet irradiation, flame treatment or the like before or after the undercoat treatment.

In the present invention, the method for coating the emulsion layer containing tabular grains, the surface protective layer and the like on the support is not particularly limited,
For example, U.S. Pat. Nos. 2,761,418 and 3,50
The multilayer simultaneous coating method described in No. 8,947, No. 2,761,791 and the like can be preferably used.

The layer structure of the photographic material of the present invention can take various forms. For example, (1) a layer containing tabular silver halide grains according to the present invention is provided on a support, and a surface protective layer made of gelatin is provided thereon. (2) A layer containing tabular silver halide grains according to the present invention is provided on a support, and a high-sensitivity spherical shape having a relatively large grain size (0.5 to 3.0 μ) or a diameter / thickness ratio is provided thereon. Of 3 or less is provided with a silver halide emulsion layer containing polyhedral silver halide grains, and further a gelatin or other surface protective layer is provided thereon. (3) A layer containing tabular silver halide grains is provided on a support, a plurality of silver halide emulsion layers are further provided thereon, and a gelatin surface protective layer is further provided thereon. (4) One silver halide emulsion layer is provided on a support, a layer containing tabular silver halide grains is further provided thereon, and a high-sensitivity silver halide emulsion layer is provided further thereon. A gelatin surface protective layer. (5) A layer containing an ultraviolet absorber or a dye, a layer containing tabular silver halide grains, a silver halide emulsion layer, and a gelatin surface protective layer are provided in this order on a support. (6) A layer containing tabular silver halide and an ultraviolet absorber or a dye, a silver halide emulsion layer, and a gelatin surface protective layer are provided in this order on a support. In these embodiments, the silver halide emulsion layers may be on both sides of the support. Further, the silver halide emulsion layer does not necessarily have to be a single layer and may be composed of a plurality of silver halide emulsion layers spectrally sensitized to different wavelengths.

The silver halide photographic light-sensitive material of the present invention is specifically,
-Ray photosensitive material (for indirect X-ray, for direct X-ray),
Plate-making photosensitive material (for example, lith film), black-and-white printing paper, black-and-white negative film, cathode ray tube display photosensitive material, silver salt diffusion photosensitive material color negative film, color reversal film, color paper, color diffusion transfer photosensitive material,
It also includes a silver dye bleaching photosensitive material, a printout photosensitive material, a heat source sensitized photosensitive material and the like.

The exposure for obtaining a photographic image may be performed using a usual method. That is, natural light (sunlight), tungsten light,
Fluorescent lamp, mercury lamp, xenon arc lamp, carbon mark lamp, xenon flash lamp, cathode dyeing tube flying spot, light emitting diode, laser light (eg gas laser, YA
Any of various known light sources including infrared light such as G laser, dye laser, semiconductor laser, etc. can be used. Further, the light may be exposed by the light emitted from the phosphor excited by the electron beam, the X-ray, the γ-ray or the α-ray. The exposure time is 1 × 10 ⁻³ seconds to 1 second which is usually used in a camera, as well as the exposure time shorter than 1 × 10 ⁻³ seconds, for example, 1 × using a xenon flash lamp or a cathode ray tube.
10 ^-4 to 1 × 10 ^-9 seconds 10 using the exposure laser beam ^-4
Exposure for 10 to ¹² seconds or the like can be used, and exposure for longer than 1 second can also be used. If necessary, the spectral composition of light required for exposure can be adjusted with a color filter.

For the photographic processing of the light-sensitive material of the present invention, known methods and known processing solutions such as those described in Research Disclosure 176, pages 28 to 30 (RD-17643) can be used. Either can be applied. This photographic processing may be either photographic processing for forming a silver image (black and white photographic processing) or photographic processing for forming a dye image (color photographic processing) depending on the purpose. The treatment temperature is usually selected between 18 ° C and 50 ° C, but it may be lower than 18 ° C or higher than 50 ° C.

The developing solution used for black-and-white photographic processing may contain a known developing agent. As developing agents, dihydroxybenzenes (for example, hydroquinone), 3-
Pyrazolidones (eg 1-phenyl-3-pyrazolidone), aminophenols (eg N-methyl-p)
-Aminophenol and the like can be used alone or in combination. Generally, other known preservatives are used in the developer.
Including alkali agents, pH buffers, antifoggants, etc., and if necessary, dissolution aids, toning agents, development accelerators (eg, quaternary salts, hydrazine, benzyl alcohol), surfactants, defoamers, hard water A softening agent, a hardener (for example, glutaraldehyde), a viscosity imparting agent and the like may be included.

As a special form of development processing, the developing agent in the photosensitive material,
For example, a method may be used in which the photosensitive material is contained in the emulsion layer and is processed in an alkaline aqueous solution for development. Among the developing agents, hydrophobic ones include those disclosed in Research Disclosure 169 (RD-16928), US Pat. No. 2,73.
It can be incorporated in the emulsion layer by various methods described in, for example, 9,890, British Patent 813,253 or West German Patent 1,547,763. Such a development treatment may be combined with a silver salt stabilization treatment with thiocyanate.

As the fixer, one having a commonly used composition can be used. As the fixing agent, in addition to thiosulfates and thiocyanates, organic sulfur compounds known to be effective as a fixing agent can be used. The fixing solution may contain a water-soluble aluminum salt as a hardening agent.

Conventional methods can be applied to form a dye image. For example, the negative-positive method (e.g., Journal of the Society of Motivation Engineers (Journal of the Society of Mot.
ion Picture and Television Engineers) Volume 61 (19
53), pp. 667-701); developed with a developer containing a black-and-white developing agent to form a negative silver image, followed by at least one uniform exposure or other suitable fog treatment. , A color reversal method for obtaining a dye positive image by subsequent color development; a silver dye bleaching method in which a photographic emulsion layer containing a dye is exposed and then developed to form a silver image, and the silver image is bleached by using this as a bleach catalyst. Used.

The color developing solution generally comprises an alkaline aqueous solution containing a color developing agent. Color developing agents are known primary aromatic amine developers such as phenylenediamines (eg 4-amino-N, N-diethylaniline, 3-methyl-4-amino-N, N-diethylaniline, 4-amino-). N-ethyl-N-β-hydroxyethylaniline, 3-methyl-4-amino-N-ethyl-N-β-hydroxyethylaniline, 3-methyl-4-amino-N-ethyl-N-
β-methanesulfoamidoethylaniline, 4-amino-
3-methyl-N-ethyl-N-β-methoxyethylaniline and the like) can be used.

In addition, L. F. A. Mason: Photographic Procing Chemistry
essing Chemistyr) (Published by Focal Press,
1966), pages 226-229, U.S. Pat. No. 2,19
3,015, 2,592,364, JP-A-48-
For example, those described in No. 64933 may be used.

If necessary, a pH buffer, a development inhibitor, an antifoggant, a water softener, a preservative, an organic solvent, a development accelerator, a carboxylic acid chelating agent, etc. can be added to the color developer. .

Specific examples of these additives include Research Disclosure (RD-17643), US Pat.
No. 723, West German publication (OLS) 2,622,950 and the like.

Reference Example 1 (1) Preparation of Comparative Cubic Emulsion Potassium bromide, ammonia and gelatin were added and dissolved, and the pAg of the silver nitrate solution and potassium bromide solution was adjusted to 7.7 while stirring in a solution maintained at 60 ° C. It was added by the double jet method while maintaining the above. After completion of the addition, the temperature was lowered to 35 ° C., soluble salts were removed by a precipitation method, and gelatin was added to adjust the pH to 6.3.

The obtained silver bromide grains were cubic grains having a ridge length of 0.8 μm. This emulsion was divided into two to give Emulsions A-1 and A-2.

Emulsion A-1 was chemically ripened using 5-benzylidene-3-ethylrhodamine, potassium chloroaurate and potassium thiocyanate.

Emulsion A-2 was chemically sensitized in the same manner as Emulsion A-1, after adding 3.96 wt% aqueous hydrogen peroxide (3.4 cc / mol Ag).

(2) Preparation of Tabular Grain Emulsion Potassium bromide and gelatin were added and dissolved, and a silver nitrate solution and potassium bromide were added by a double jet method to a solution kept at 63 ° C while stirring. After addition is complete, 3
After cooling to 5 ° C to remove soluble salts, 40
The temperature was raised to ° C and gelatin was added to adjust the pH to 6.8.

The tabular silver bromide grains obtained had an average diameter of 1.23 μm, a thickness of 0.13 μm, and an average diameter / thickness ratio of 9.7.
It was. This emulsion was divided into two to give Emulsions B-1 and B-2.

Emulsion B-1 was chemically ripened in the same manner as Comparative Cubic Emulsion A-1. Emulsion B-2 was chemically ripened after the addition of hydrogen peroxide solution as in Emulsion A-2.

(3) Preparation of coating sample Emulsions A-1, A-2, B- which have been subjected to the above-mentioned optimum chemical sensitization
1 and B-2 were each divided into 2 minutes, dissolved at 40 ° C., and 200 mg of potassium iodide was added per 1 mol of silver. Then 2
Spectral sensitizer D-17 was added to one of the divided emulsions in an amount of 500 mg (7.3 × 10 ^-4 mol) per mol of silver, the other was not added, and a stabilizer (4-hydroxy- 6-methyl-1,3,3a, 7-tetrazaindene and 2,6-
Bis (hydroxyamino) -4-diethylamino-1,
3,5-triazine), coating aid (sodium p-dodecylbenzenesulfonate) and hardener (sodium 2,4-dichloro-6-hydroxy-s-triazine) are added to make gelatin the main component. It was coated on a polyethylene terephthalate (PET) film support together with the surface protective layer and dried.

(4) Evaluation of photographic performance After the coated sample was exposed to blue light at 410 nm for 0.1 second using a bandpass filter having a peak of transmitted light,
Developer "Hilendor" manufactured by Fuji Photo Film Co., Ltd.
It was developed at 20 ° C. for 4 minutes, fixed, washed with water and dried.

The results are shown in Table 1. The relative sensitivity here is the fog value +
It was calculated from the exposure amount required to obtain a blackening degree of 0.2.

From the results shown in Table 1, the emulsion prepared without using the hydrogen peroxide solution shows a large decrease in blue light sensitivity due to the addition of the spectral sensitizer. On the other hand, when the hydrogen peroxide solution is used, In the tabular grain emulsion, intrinsic desensitization by the spectral sensitizer is significantly suppressed.

Potassium bromide Preparation of Reference Example 2 (1) tabular emulsion was kept thioether _{(HO (CH 2) 2 S} (CH 2) 2 S (CH 2) 2 OH), and dissolved 60 ° C. by adding gelatin While stirring in the solution, a silver nitrate solution and a mixed solution of potassium iodide and potassium bromide were added by the double jet method.

After the addition was completed, the temperature was lowered to 35 ° C., the soluble salts were removed by the precipitation method, the temperature was raised again to 40 ° C., gelatin was added and dissolved, and the pH was adjusted to 6.8. The obtained emulsion was designated as Emulsion C.

The tabular silver halide grains obtained had an average diameter of 0.88.
The thickness is 0.14 μm in μm, and the average diameter / thickness ratio is 6.3.
And the silver iodide content was 3 mol%. This emulsion was divided into two to give Emulsions C-1 and C-2.

Emulsion C-1 was chemically ripened with 5-benzylidene-3-ethylrhodamine, potassium chloroaurate and potassium thiocyanate to optimize the chemical sensitization at a fog of 0.02.

Emulsion C-2 was added with 3.96 wt% hydrogen peroxide water (4.1 cc / mol Ag), and then a chemical sensitizer similar to that of emulsion C-1 was used to obtain a fog of 0.02 as a substitute sensitization. Was optimized.

(2) Preparation of coating sample Emulsions C-1 and C-2 were divided into pots and dissolved at 40 ° C, and then spectral sensitizers D-15 or D-23 were added in the amounts shown in Table 2. Further, potassium iodide is added to 20 mol per mol of silver.
0 mg was added, and then a stabilizer, a coating aid and a hardener were added in the same manner as in Example 1 and coated on a polyethylene terephthalate (PET) film support together with a surface protective layer.

(3) Evaluation of photographic performance A coated sample was exposed to blue light as in Reference Example 1 and a sample was exposed to white light only through an optical wedge without using a bandpass filter. It was developed in the same manner as described above and evaluated for photographic performance.

From Table 2, it can be seen that when hydrogen peroxide solution is not used during the chemical sensitization, the intrinsic desensitization is greatly caused with the addition amount of the spectral sensitizer, and the white light sensitivity reaches the ceiling with a small addition amount.

On the other hand, in the case of the present invention using a hydrogen peroxide solution, not only the intrinsic desensitization is suppressed even when a large amount of the spectral sensitizer is added, but rather the sensitization is shown, and the white light sensitivity is remarkably increased. It will be understood that the present invention is an extremely excellent technique for spectral sensitization.

Reference Example 3 Emulsion C optimally chemically sensitized as in Reference Example 2
-1 and C-2 were divided into pots and each of the spectral sensitizers shown in Table 3 was added in an amount of 8 × 10 ^-4 mol per mol of silver, and potassium iodide, a stabilizer and a stabilizer were added in the same manner as in Reference Example 2. A coating aid and a hardener were added and coated on a cellulose triacetate film support together with the surface protective layer by the coextrusion method.

Next, this coated sample was exposed to blue light in the same manner as in Reference Example 2 and white light was exposed only through the optical wedge without using a bandpass filter, and was developed and fixed in the same manner as in Reference Example 1. It was washed with water and dried.

The results obtained are shown in Table 3. By using hydrogen peroxide solution during chemical sensitization, intrinsic desensitization is suppressed even when a desensitizing amount of spectral sensitizer is added, and the white light sensitivity is significantly increased. You can see that

Reference Example 4 On a cellulose triacetate film support, a multi-layer color light-sensitive material sample 101 composed of each layer having the following composition was prepared.

(Sample 101) First layer: Anti-halation layer (AHL) Gelatin layer containing black colloidal silver Second layer: Intermediate layer (ML) Gelatin layer containing emulsified dispersion of 2,5-di-t-octylhydroquinone Third layer Layer: First red-sensitive emulsion layer (RL ₁ ) Silver iodobromide emulsion E-1 (silver iodide 5 mol%) Average grain size 0.70 μ Thickness 0.10 μ Aspect ratio 7.0 Silver 1.8 g / m ² Spectral sensitizer D-21 ... 9 × 10 ⁻⁴ mol per 1 mol of silver Spectral sensitizer D-23 …… 2.3 × 10 ⁻⁴ mol per mol of silver Coupler EX-1 ... ... 0.04 mol to 1 mol of silver Coupler EX-5 ... 0.003 mol to 1 mol of silver Coupler CX-1 ... 0.0006 mol to 1 mol of silver Fourth layer: second red sensitive emulsion layer (RL ₂₎ silver iodobromide emulsion F-1; silver iodide 7 mol% average particle size 1.0μ thickness 0. To 5μ aspect ratio 6.7 silver 1.4 g / m ² spectral sensitizers D-21 ...... 1 mol of silver relative to 4.5 × 10 ^-4 mol spectral sensitizer D-23 ...... silver mole 1.8 × 10 ⁻⁴ mol Coupler EX-2 ... 0.02 mol per 1 mol of silver Coupler EX-5 ... 0.0016 mol per 1 mol of silver Fifth layer: intermediate layer (ML) Same as the second layer Sixth layer: First green-sensitive emulsion layer (GL ₁ ) Silver iodobromide emulsion G-1 Silver iodide 4 mol% Average grain size 0.60 Thickness 0.10 Aspect ratio 6.0 Silver 1.5 g / m ² Spectral sensitizer D-17: 5.25 × 10 ⁻⁴ mol per mol of silver Spectral sensitizer D-20: 1.75 × 10 ⁻ per mol of silver ⁴ mol coupler EX-4 0.008 mol per 0.05 mol coupler EX-6 ...... 1 mol of silver against ...... 1 mol of silver coupler CX-1 ...... silver 1 mode 0.0015 mol seventh layer against: second green-sensitive emulsion layer (GL ₂₎ silver iodobromide emulsion J-1; silver iodide 6 mol% average particle size 1.00μ thickness 0.15μ aspect ratio 6 1.7 Silver 1.6 g / m ² Spectral sensitizer D-17 ... 3.8 × 10 ⁻⁴ mol per mol of silver Spectral sensitizer D-20 ... 1.2 against 1 mol of silver × 10 ^-4 mol Coupler EX-3 ... 0.003 mol to 1 mol of silver Coupler CV-2 ... 0.017 mol to 1 mol of silver Eighth layer: yellow filter layer (YFL) in gelatin aqueous solution. Yellow colloidal silver and 2.5-di-t-
A gelatin layer containing an octyl hydroquinone emulsion dispersion.

Ninth layer: First blue-sensitive emulsion layer (BL ₁ ) Silver iodobromide emulsion K-1; Silver iodide 6 mol% Average grain size 0.60 μ Thickness 0.10 μ Aspect ratio 6.0 Silver 1.5 g / m ² Spectral sensitizer D-13 ... 8 × 10 ⁻⁴ mol per 1 mol of silver Coupler EX-7 ... 0.25 mol per 1 mol of silver Coupler CX-1 0.015 mol 10th layer : Second blue-sensitive emulsion layer (BL ₂ ) Silver iodobromide emulsion L-1; Silver iodide 6 mol% Average particle size 1.20 μ Thickness 0.20 μ Aspect ratio 6.0 Silver 1.1 g / m ² spectrum Sensitizer D-13 ... 4 × 10 ⁻⁴ mol per 1 mol of silver Coupler EX-7 ... 0.06 mol per 1 mol of silver 11th layer: protective layer (PL) trimethylmethanoacrylate particles ( Diameter about 1.5μ)
Coated gelatin layer containing.

In addition to the above composition, a gelatin hardening agent H-1 and a surfactant were added to each layer.

The sample manufactured as described above was designated as Sample 101.

Coupler EX-1 EX-2 EX-3 EX-4 EX-5 EX-6 EX-7 CX-1 CX-2 H-1 Third layer, fourth layer, sixth layer, seventh layer in Sample 101,
Emulsions 9th and 10th layers E-1, F-1, G-1,
J-1, K-1, and L-1 are replaced by E-2, F-2, and G-, respectively.
Sample 1 except that it was replaced with 2, J-2, K-2, L-2
A sample manufactured in the same manner as 01 was used as sample 102.

Next, a method for preparing the above emulsion will be described below.

A mixed solution of a silver nitrate solution, a potassium iodide solution and potassium bromide was added by a double jet method to an aqueous solution in which potassium bromide and gelatin were added and dissolved and kept at 50 ° C while stirring.

After the addition, the soluble salts were removed by a sedimentation method, and then gelatin was added and dissolved to adjust the pH to 6.2.

This emulsion was divided into 2 minutes. (Emulsion E-1 and Emulsion E-2) Emulsion E-1 was prepared by using sodium thiosulfate, potassium chloroaurate and potassium thiocyanate under the optimum conditions when the fog was 0.01 in the development processing described later.・ Sulfur sensitized. (Comparative Emulsion E-1) In Emulsion E-2, 10 cc of 3.96 wt% hydrogen peroxide per mol of silver was added immediately before the start of gold / sulfur sensitization, and then fog was zero as in Emulsion E-1. Gold / sulfur sensitization, which is the optimum condition for 0.01, was applied.

(Emulsion E-2 of the Present Invention) Thereafter, an emulsion prepared by appropriately changing the amount and temperature of the potassium iodide solution so as to have a predetermined halogen composition, average particle diameter, thickness, and aspect ratio was used, and Emulsions as described (Comparative emulsions F-1, G-1, J-1, K-1, L-1, Emulsions F-2, G-2, J-2, K-2, L-2 of the present invention) Was prepared.

The sample prepared as described above is subjected to wet exposure with white light,
We compared the sensitivities of the red, green, and blue layers. The reference point used to determine the sensitivity is the optical density [fog + 0.
2].

The development process used here is 38 ° C. according to the following process steps.
I went to.

Color development 3 minutes 15 seconds Bleaching 6 minutes 30 seconds Washing with water 2 minutes 10 seconds Fixing 4 minutes 20 seconds Washing with water 3 minutes 15 seconds Stability 1 minute 05 seconds The treatment liquid composition used in each step is as follows. It was

Color developer Diethylenetriamine pentaacetic 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 0.4 g 4- (N-ethyl-N-β-hydroxyethylamino) -2-methylaniline sulfate 4.5 g Water was added to 1.0 pH 10.0 Bleaching solution Ethylenediaminetetraacetic acid ferric ammonium salt 100 0.0 g Ethylenediaminetetraacetic acid disodium salt 10.0 g Ammonium bromide 150.0 g Ammonium nitrate 10.0 g Water added 1.0 pH 6.0 Fixing solution Ethylenediaminetetraacetic acid disodium salt 1.0 g Sodium sulfite 4.0 g Ammonium thiasulfate aqueous solution (70%) 175.0 ml Sodium bisulfite 4.6g Water was added to 1.0 pH 6.6 Stabilizer Formalin (40%) 2.0ml Polyoxyethylene-p-monononylphenyl ether (average degree of polymerization ≈10) 0.3g Water In addition, the obtained results are shown in Table 4.

From the results shown in Table 4, the relative sensitivity can be remarkably improved by using hydrogen peroxide, which is an oxidizing agent, during the chemical aging.

Example 1 (1) Preparation of Tabular Silver Iodobromide Emulsion and Coated Sample Preparation was carried out in the same manner as the eyelids except that the temperature was raised to 75 ° C. in the grain formation of Reference Example 2. The tabular grains obtained had an average diameter of 1.57 μm, a thickness of 0.14 μm and a grain diameter / thickness ratio of 11.2. This emulsion was designated as Emulsion M.

Next, divide this emulsion into emulsions M-1, M-2, M-3, M
It was set to -4. Emulsion M-1 was subjected to gold and sulfur sensitization in the same manner as Emulsion C-1 of Reference Example 2 so as to be optimum. Emulsion M-2
In the same manner as in the emulsion C-2 of Reference Example 2, 3.96 wt% hydrogen peroxide solution was added in an amount of 4.4 cc per mol of silver, and then gold and sulfur sensitization were used in combination for optimum performance. Emulsion M-3,
M-4 was chemically sensitized in the same manner as Emulsion M-2, and then 1 g of sodium p-toluenesulfinate was added per mol of silver.
What was added (5.6 × 10 ⁻³ mol) was designated as emulsion M-3, and what was added 2 g was designated as emulsion M-4.

Emulsions M-1, M-2, M-3 and M-4 were dissolved at 40 ° C. to prepare spectral sensitizer D-17, 585 mg (8.6 × 10 ^-4 mol) and potassium iodide 200 mg to silver 1 mol. It was added around. Furthermore, 4-hydroxy-6-methyl-1, as a stabilizer,
3,3a, 7-tetrazaindene, 2,6-bis (hydroxyamino) -4-diethylamino-1,3,5-triazine, polyacrylamide having an average molecular weight of 47,000, a coating aid and a hardener are used. Along with the surface protection layer added and coated, it was coated on a PET support by the simultaneous extrusion method. The thickness of the surface protective layer is 1.2 μm, and the coated silver amount is 2.5 g /
m ²

Emulsions M-1, M-2, M-3 and M-4 were respectively coated immediately after chemical ripening, those which were stored in a refrigerator at 8 ° C for 4 weeks and then coated and those after chemical ripening. What was melt | dissolved at 40 degreeC for time, and what was aged was applied.

(2) Evaluation of Photographic Performance and Graininess The above coated sample was exposed to colored light and white light in the same manner as in Reference Example 3. The exposed sample is 20 times with the following developing solution.
After development at 4 ° C. for 4 minutes, it was fixed with a fixing solution and further washed with water.

The results are shown in Table 5. Here, the relative sensitivity is the fog value +
It was calculated from the exposure amount required to obtain a blackening degree of 1.0.
The RMS value representing the graininess was measured with an aperture of 48 × 48 μm, and the value at a density of 1.0 was shown.

Developer 1-phenyl-3-pyrazolidone 0.5 g Hydroquinone 20.0 g Ethylenediaminetetraacetate sodium 2.0 g Potassium sulfite 60.0 g Boric acid 4.0 g Potassium carbonate 20.0 g Potassium bromide 5.0 g Diethylene glycol 30.0 g Water And add 1.

Bring pH = 10.0 with NaOH.

Fixer The following fixer was used.

Ammonium thiosulfate 200.0 g Sodium sulfite (anhydrous) 20.0 g Boric acid 8.0 g Ethylenediaminetetraacetic acid dinatrium sodium 0.1 g Aluminum sulfate 15.0 g Sulfuric acid 2.0 g Glacial acetic acid 22.0 g Water was added 1 (pH is Adjust to 4.2) From the results shown in Table 5, the following things became clear.

Emulsions M-2, M-3, and M-4 containing hydrogen peroxide have a higher sensitivity and are less deteriorated in graininess than Emulsion M-1 which does not contain hydrogen peroxide.

Emulsion M-2 using only hydrogen peroxide becomes less sensitive over time. Emulsion M-3 of the present invention, which is a combination of hydrogen peroxide and sodium p-toluenesulfinate,
M-4 is highly preferable because it is stable with time and can be stably produced in producing a light-sensitive material.

Further, instead of sodium p-toluenesulfinate, the above-mentioned reducing agents such as resorcin, DL-glucose, N
-Formyl-N'-p-tolylhydrazine and sodium benzenesulfinate were prepared in the same manner as in Example 5 to give 5.6.
Addition of × 10 ^-3 equivalent / mol silver showed almost the same effect as addition of sodium p-toluenesulfinate.

Regarding the timing of adding these reducing agents, the sensitivity may be somewhat lowered when they are added in the initial stage, but it is possible to further reduce the fluctuation of photographic properties with respect to the chemical ripening time.

Example 2 The same emulsion M-1 and emulsion M-4 as those used in Example 1 were used, the spectral sensitizers shown in Table 6 were added, and coating and development were performed in the same manner as in Example 1 to evaluate photographic performance. did.

As can be seen from the results in Table 6, using the method of the present invention,
Not only is high sensitivity obtained with almost no deterioration of the preferred graininess, but also stability over time is excellent.
The present invention is a very effective technique for stably producing a light-sensitive material that is spectrally sensitized and has high sensitivity and excellent graininess.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadashi Ikeda, 210 Nakanuma, Minamiashigara City, Kanagawa Prefecture Fuji Photo Film Co., Ltd. Examiner Hiroshi Fukatsu (56) References JP 61-3134 (JP, A)

Claims (2)

[Claims] 1. A method for producing a photosensitive tabular silver halide grain emulsion having a grain size three times or more the grain thickness, wherein hydrogen peroxide and a peroxy acid salt are prepared before the chemical ripening of the emulsion is completed. To at least one of the oxidants consisting of ozone, followed by the addition of the reducing substance, and the emulsion being spectrally sensitized with an amount of spectral sensitizer which results in desensitization when no oxidant is added. A method for producing a silver halide emulsion, characterized in that 2. A silver halide emulsion produced by adding at least one of an oxidizing agent consisting of hydrogen peroxide, a peroxy acid group or ozone until the completion of chemical ripening, and then adding a reducing substance. Further, the emulsion is spectrally sensitized with an amount of a spectral sensitizer which brings about desensitization when an oxidizing agent is not added, and the grain size of silver halide grains contained in the emulsion is 3 times or more the grain thickness. A silver halide photographic light-sensitive material having at least one layer containing an emulsion which is a tabular silver halide emulsion.