JPS6258237A - Silver halide emulsion and its production and silver halide photosensitive material using said silver halide emulsion - Google Patents

Abstract

PURPOSE:To improve the reciprocity law failure characteristic of high sensitivity and low illuminance and to improve a fogging characteristic with lapse of time by incorporating silver halide particles contg. silver iodide whose spherical particles are grown as seed particles and are subjected to halogen substn. at the specific point of time into the titled material. CONSTITUTION:The emulsion contg. the silver halide twin particles having >=5:1 average aspect ratio is obtd. by growing the multiple twin particles and/or the spherical particles obtd. from the multiple twins as the seed particles and subjecting the same to the halogen substn. by iodide corresponding to 0.005-20mol%, more preferably 0.01-10mol% at an optional point of the time between the time when 5-95mol% of the entire particles is formed. The seed emulsion contg. the multiple twin particles has further preferably >=50wt% ratio of the multiple twins with regard to the total seed particles contained in the emulsion. The seed emulsion contg. the spherical particles is obtd. by maturing the emulsion contg. the multiple twin particles in the presence of the silver halide emulsion. The emulsion is more particularly preferably obtd. by maturing the same for 30sec-5min under the conditions of 35-45 deg.C, 0.4-110mol/liter ammonia and 0.03-0.5mol/liter potassium bromide.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a silver halide emulsion, a method for producing the same, and a silver halide photosensitive material using this emulsion. In particular, the present invention relates to a silver halide emulsion mainly composed of twin crystal grains having high sensitivity, improved low-illuminance reciprocity law failure characteristics, and improved capri characteristics over time, a method for producing the same, and a silver halide photosensitive material using the silver decogenide.

[Conventional technology]

In recent years, the sensitivity of color negative films has increased and the format has become smaller, and the demand for higher image quality of silver halide photographic materials has become extremely strong. In response to these demands, much research has been carried out focusing on improving silver halide emulsions. In particular, research using monodisperse emulsions has been conducted regarding techniques for controlling the size and size distribution of silver halide grains, the halogen composition structure inside the grains, the crystal shape, etc.

Attempts have also been made to control the growth of silver halide emulsions consisting of monodisperse twin grains, which have been considered particularly difficult to control. Such techniques are described in Japanese Patent Publication No. 58-36762, Japanese Patent Application Laid-Open No. 52-153428, Japanese Patent Application Laid-open No. 54-118823, and the like.

Although the silver halide emulsions obtained by these techniques have high sensitivity and excellent graininess, they have problems such as low sensitivity in low-light long-term exposure and significant changes in fog over time due to heat, and improvements are desired. It was rare.

Furthermore, JP-A-60-147727 discloses that the average iodine content of two adjacent layers having a homogeneous iodine distribution of silver halide grains having a multilayer structure and an aspect ratio of 5 or less is disclosed. By using silver halide grains in which the difference is 10 mol% or more, the average iodine content of the outermost layer is 40 mol% or less, and the above-mentioned silver halide grains are chemically sensitized,
A silver halide photographic material with improved pressure properties such as stress blur is disclosed. However, this photosensitive material also had problems with sensitivity, low-light reciprocity law failure characteristics, and changes in fog over time due to heat.

[Purpose of the invention]

A first object of the present invention is to provide a silver halide emulsion mainly consisting of twin crystals with improved low-light reciprocity law failure characteristics, a method for producing the same, and a silver halide photosensitive material using silver halide. .

A second object of the present invention is to provide a silver halide emulsion mainly consisting of twin crystals that shows little change in fog over time, a method for producing the same, and a silver halide photosensitive material using silver halide.

[Structure and operation of the invention]

The above purpose is to grow multi-twinned particles and/or spherical particles obtained from multi-twinned particles as seed particles.
0.005 to 20 at any time during the formation of mol%
Achieved by obtaining an emulsion containing twinned silver halide grains with an average aspect ratio of less than 5:1 by performing halogen substitution with iodide equivalent to mol%, more preferably 0.01 to 10 mol%. be done.

Examples of the iodide to be added include potassium iodide, an aqueous solution thereof, silver iodide, and a silver iodide emulsion. In this case, if the amount of iodide added acid is less than 5 mol % of the total silver halide, the effect of the present invention will not be achieved, and if it is more than 95 mol %, sensitivity will decrease, both of which are not preferred.

For example, the multi-twinned grains according to the present invention have a pBr of −0,7
It can be obtained by adding a water-soluble silver salt solution, or a water-soluble silver salt solution and a water-soluble halogen compound solution to a water-soluble protective colloid solution, such as a gelatin solution, stirred under conditions of -2.0.

Preferably, the multi-twinned grains are dispersed in a water-soluble colloidal dispersion medium to form a dispersion, ie, an emulsion, and are subjected to the growth process.

The emulsion containing seed particles to be subjected to the growth process is hereinafter referred to as a seed emulsion.

The seed emulsion containing multiple twinned grains according to the present invention (hereinafter referred to as multiple twinned seed emulsion) has a ratio of power-harvesting twins of 30% or more to all seed grains contained in the emulsion. The content is preferably 50% by weight or more, and more preferably 50% by weight or more.

The morphology of multiple twins is explained in "Basic Silver Salt Photography of Photographic Engineering" P.
163 to 166 (Corona Inc.) and are classified and described in detail, and can be distinguished using an electron microscope.

The seed emulsion containing spherical grains according to the present invention (hereinafter referred to as spherical seed emulsion) is obtained by ripening the emulsion containing multiple twinned grains obtained by the above method in the presence of a silver halide emulsion. . Particularly preferable conditions include a temperature of 35
~45℃ ammonia 0.4 to 1.0 mol/liter,
Potassium bromide 0.03 to 0.5 mol/liter 30
It is obtained by aging for 2 to 5 minutes. In the present invention, the monodispersity of the silver halide emulsion is better obtained by using a spherical seed emulsion than by a multiple twin seed emulsion or a seed emulsion containing multiple twin grains and spherical grains obtained from multiple twins. It is preferable from the point of view.

The seed emulsion according to the present invention, formed by mixing silver ions and halogen ions, can be transferred to the next step in the same container, or can be prepared in advance in a separate container.

The seed particles contained in the seed emulsion preferably consist essentially of the seed particles of the present invention. The ratio of seed particles other than the seed particles of the present invention is preferably about 20% at most.

The halogen composition of the seed emulsion comprising multiple twin grains and/or spherical seed grains according to the present invention contains 30 mol% of silver iodide.
It is preferable that silver iodobromide is contained in the following range,
It is more preferably 10 mol% or less, particularly preferably 5 mol% or less.

The growth of seed particles according to the present invention has a par of 0.7 to 4.
Preferably, the condition is 0. If it is outside this range, the monodispersity will be low, and it may be difficult to obtain the desired emulsion. A more preferable pBr range is 1.0 to 3.0.

In the present invention, in order to grow seed grains, it is preferable to mix a water-soluble silver salt solution and a water-soluble halide solution with the seed emulsion.

In the present invention, the water-soluble silver salt solution or the water-soluble silver salt solution and the water-soluble halide solution in the seed particle growth step are:
Preferably, the reaction is carried out within a range of 30 to 100% of the critical crystal growth rate.

The critical velocity of a crystal is defined as the limit at which new nuclei are not substantially generated during the crystal growth process, but "substantially no generation" means that the superposition of newly generated crystal nuclei exceeds the total silver halide weight. This means that it is 20% or less, more preferably 10% or less.

In the present invention, the step of growing seed grains is preferably a step of growing silver halide grains having an average grain size twice or more that of the seed grains.

In the seed grain growth process of the present invention, various silver halide solvents can be present for the purpose of accelerating the crystal growth rate.

Silver halide solvents used in the present invention include (Al U.S. Pat. No. 3,271,157, U.S. Pat. No. 3,531,289, U.S. Pat.
-1019 and the same (organic thioethers described in each publication of A154-158917, (b) JP-A No. 5
No. 3-82408, No. 55-77737, No. 56-2
Thiourea derivatives described in the specifications of Patent Publication No. 9829 and Japanese Patent Publication No. 5B-30571, tC) JP-A No. 53-144
AgX solution having a thiocarbonyl group sandwiched between an oxygen or sulfur atom and a nitrogen atom described in JP-A No. 319, (d) imidazoles described in JP-A-54-100717, (e ) sulfite, (f) thiocyanate, (g) ammonia, (hl JP-A-57-19622
(1) mercaptotetrazoles described in JP-A No. 57-202531; (1) mercaptotetrazoles described in JP-A No. 58-54333; (1) mercaptotetrazoles described in JP-A-58-54333; etc.

(bl) Next, specific examples of these silver halide solvents (a) to (3) will be given. Note that the solvent used in the present invention is not limited to these exemplified compounds.

HO-(C1li) t-5-(CIlg) z-3-
(Cllx) z-OHCHt -NHCO-C1l
tcII□COO11■ CHI-3-CIl□CHtSCtHsCHz-NHC
O-CHFuCl1tCHaCHg-5-CHCHg-5
-CHoCl1iCOOHCH3 161KgS(h (flNll, SCN, KSCN (glNH401( 12' CH.

(j) +1 In the present invention, it is preferable that the pn of the particle growth atmosphere in step □ for growing seed particles is in the range of 2.0 to 13.0. A range of 3.0 to 12.0 is more preferred.

In the present invention, the temperature of the emulsion in the step of growing seed grains can range from 30°C to 80°C. It is more preferable to carry out the reaction at a temperature of 35°C to 65°C.

In the present invention, water-soluble silver salts and water-soluble halides used in the production of seed particles and the growth of seed particles can be those commonly used in the art, and examples of water-soluble silver salts include silver nitrate, Examples of water-soluble halides include potassium bromide, sodium bromide, ammonium bromide, and potassium iodide.

In the silver halide emulsion obtained in the present invention, the composition distribution of silver iodide within the grains may be localized (unevenly distributed) or uniform. An example of localized silver iodide is a core made of silver iodobromide with a high silver iodide content and a shell made of silver iodobromide or pure silver iodobromide with a low silver iodide content. A shell type is preferred.

The core/shell type emulsion is made by adding flAg and p
It can be obtained by changing the composition of the water-soluble halide liquid in the core and shell parts in the double jet method under the control of l+.

The core/shell type silver halide grains preferably used in the present invention have a grain structure composed of two or more layers having different silver iodide contents, and the two or more layers have different silver iodide contents.
It is preferable that the silver iodide content in the outermost layer (shell part) of the uppermost layers is lower than the silver iodide content in the inner layer (core part). The silver iodide content of the core portion may be 5 to 40 mol%, more preferably 6 to 30 mol%, more preferably 7 to 20 mol%.

The silver iodide content in the shell part is preferably less than 5 mol%.The difference in content between the core part with a high silver iodide content and the shell part with a low silver iodide content may have a sharp boundary. It may also be a continuous change that is not necessarily obvious. As a method of continuously changing the halogen composition at the boundary between the core and the shell, a method of gradually changing the composition of the added halide liquid in the double jet method can be used. Further, the silver iodide composition in the core part and the shell part may be unevenly distributed.

Further, the ratio of the shell portion of the core/shell type silver halide grains is preferably 10 to 80%, more preferably 1
It is 5 to 70%, particularly preferably 20 to 60%.

- The distribution state of silver iodide in silver halide grains can be detected by various physical measurement methods. It can also be investigated by measuring the luminescence at .

The silver halide emulsion of the present invention may be polydisperse or monodisperse. Preferably, it is monodisperse. Here, a monodisperse silver halide emulsion is one in which the weight of silver halide grains contained within a grain size range of ±20% around the average grain size r is 60% or more of the total weight of silver halide grains. say. It is preferably 70% or more, particularly preferably 80% or more.

Here, the average particle diameter 7 is defined as the particle "5" when the frequency ni of particles having particle diameter rt and "i3 product n7
5 people).

In the case of spherical silver halide grains, the grain size referred to here means the diameter thereof, and in the case of grains having shapes other than spherical, the diameter when its projected image is converted into a circular image of the same area.

The particle size can be obtained, for example, by enlarging the particles 10,000 to 50,000 times with an electron microscope and measuring the particle diameter or projected area on the print. (The number of grains to be measured is 1000 or more at random.) The silver halide grains contained in the silver halide emulsion of the present invention have an average aspect ratio of less than Sa1. If the average aspect ratio is 5:1 or more, the effects of the present invention will not be exhibited due to insufficient monodispersity.

The average aspect ratio is preferably in the range of 1:1 to 5:1.
, 1.5:1 to 4:1 are more preferable.

The aspect ratio here is (particle diameter): (thickness)
This is the ratio of The diameter of a silver halide grain here refers to the diameter of an area equal to the projected area of the grain.

Moreover, the average aspect ratio is the average value of the aspect ratios of the entire photosensitive particles.

The silver halide grains used in the present invention are formed into complex salts (including complex salts) including cadmium salts, zinc salts, lead salts, thallium salts, and iridium salts in the process of forming and/or growing the grains.
By adding metal ions using at least one selected from rhodium salts (complex salts containing) and iron salts (complex salts containing), these metal elements can be contained inside the particles and/or on the particle surfaces. Further, by placing the particles in an appropriate reducing atmosphere, reduction sensitizing nuclei can be provided inside the particles and/or on the particle surfaces.

In the silver halide emulsion of the present invention, unnecessary soluble salts may be removed after the growth of silver halide grains is completed, or they may remain contained. When removing the salts, please refer to Research Disc.
Disclosure) 17643.

The silver halide emulsion of the present invention can be chemically sensitized by conventional methods. That is, a sulfur sensitization method, a selenium sensitization method, a reduction sensitization method, a noble metal sensitization method using gold or other noble metal compounds, etc. can be used alone or in combination.

The silver halide emulsion of the present invention is disclosed in British Patent No. 618, for example.
, No. 061, No. 1,315,755, No. 1,396,
No. 696, Japanese Patent Publication No. 44-15748, U.S. Patent No. 1,
No. 574,944, No. 1.623,499, No. 1,6
No. 73,522, No. 2,278,947, No. 2,39
No. 9,083, No. 2,410,689, No. 2,419
, No. 974, No. 2,448.060, No. 2.487.
No. 850, No. 2.518゜698, No. 2,521,9
No. 26, No. 2,642,361, No. 2゜694, 6
No. 37, No. 2,728,668, No. 2,739,06
No. 0, No. 2,743.182, No. 2,743.183
No. 2,983.609, No. 2,983,610, No. 3,021,215, No. 3,026゜203,
No. 3,297,446, No. 3,297,447, No. 361.564, No. 3.411,914, No. 3
, No. 554,757, No. 3,565,631, No. 3,
No. 565,633, No. 3,591,385, No. 3,6
No. 56,955, No. 3,761,267, No. 3,77
2゜031, 3,857,711, 3,891
, No. 446, No. 3901.714, No. 3,904.
No. 415, No. 3,930,867, No. 3,984,2
No. 49, No. 4,054,457, No. 4,067.74
No. 0, Research Disclosure
h old 5-closure) No. 12008, No. 1345
No. 2, No. 13654, T.H. James “
The Theory of the Photographic Process J (T, II.

James, The Theory of tl+e
l'photographic Process) 4t
ht! d, Macmillan 197
It is preferable to carry out sensitization using the chemical sensitizers and sensitization methods described in 7, pages 167 to 76.

Sensitizing dyes include cyanine dyes, merocyanine dyes,
Complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, steryl dyes and hemioxanol dyes are used.

Particularly useful dyes include cyanine dyes, merocyanine dyes,
and a complex merocyanine pigment. Any of the nuclei commonly used for cyanine dyes can be used as the basic heterocyclic nucleus for these dyes. That is, viroline nucleus, oxazoline nucleus, thiazoline nucleus, pyrrole nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus, imidazole nucleus, tetrazole nucleus, pyridine nucleus, and a nucleus in which an alicyclic hydrocarbon ring is fused to these nuclei: and these. A nucleus in which an aromatic hydrocarbon ring is fused to the nucleus, that is, an indolenine nucleus,
Benzindolenine nucleus, indole nucleus, benzoxazole nucleus, naphthoxazole nucleus, benzothiazole nucleus,
These include naphthothiazole nucleus, benzoselenazole nucleus, benzimidazole nucleus, and quinoline nucleus. These nuclei are
May be substituted on carbon atoms.

Merocyanine dyes or complex merocyanine dyes have a pyrazolin-5-one nucleus, a thiohydantoin nucleus, a ? -Thioxazolidine-2
．． A 5- to 6-membered heterocyclic nucleus such as a 4-dione nucleus, a thiazolidine-2,4-dione nucleus, a thiazolidine-2,4-dione nucleus, a rhodanine nucleus, and a thiobarbyl nucleus can be applied.

Sensitizing dyes used in useful blue-sensitive silver halide emulsion layers include, for example, West German Patent No. 929.080, US Pat. No. 2,231.658, US Pat. No. 776, No. 2,519,001, No. 2
, No. 912.329, No. 3.656.959, No. 3,
No. 672.897, No. 3,694,217, No. 4.0
No. 25.349, No. 4,046.572, British patent l
, No. 242.588, Special Publication No. 44-14030, No. 5
Examples include those described in No. 2-24844. Further, useful sensitizing dyes used in green-sensitive silver halide emulsions include, for example, U.S. Pat.
No. 1, No. 2 072.908, No. 2,739.149
No. 2,945.763, British Patent No. 505,979
Typical examples include cyanine dyes, merocyanine dyes, and composite cyanine dyes such as those described in No. Furthermore, useful sensitizing dyes used in red-sensitive silver halide emulsions include, for example, U.S. Pat. , No. 629, same 2
Typical examples thereof include cyanine dyes, merocyanine dyes, and composite cyanine dyes as described in, eg, No. 776.280. Furthermore, cyanine dyes, merocyanine dyes or composite cyanine dyes such as those described in U.S. Pat. No. 2,213,995, U.S. Pat. It can be advantageously used in green-sensitive silver halide emulsions or red-sensitive halogen emulsions.

These sensitizing dyes may be used alone or in combination. Combinations of sensitizing dyes are often used, especially for the purpose of supersensitization. Typical examples are Special Publications No. 43-4932, No. 43-4933, No. 4
No. 3-4936, No. 44-32753, No. 45-25
No. 831, No. 45-26474, No. 4641627, No. 46-18107, No. 47-8741, No. 47
-11114, 47-25379, 47-37
No. 443, No. 48-28293, No. 48-38406
No. 4B-38407, No. 4B-38408, No. 4B-41203, No. 48-41204, No. 49-
No. 6207, No. 50-40662, No. 53-1237
No. 5, No. 54-34535, No. 55-1569, JP-A No. 50-33220, No. 50-33828, No. 5
No. 0-38526, No. 51-107127, No. 51-
No. 115820, No. 51-135528, No. 51-1
No. 51527, No. 52-23931, No. 52-519
No. 32, No. 52-104916, No. 52-10491
No. 7, No. 52-109925, No. 52-110618
No. 54410118, No. 56-25728, No. 57-1483, No. 58-10753, No. 5B-91
No. 445, No. 5B-153926, No. 59-1145
No. 33, No. 59-116645, No. 59-11664
No. 7, U.S. Patent No. 2,688,545, U.S. Patent No. 2,911
．． No. 229, No. 3, 3!117, No. 060, No. 3,
5o6.44a, 3,578.447, 3,6
No. 72,898, No. 3,679゜428, No. 3,76
9.301, 3,814.609, 3゜837
．． It is described in No. 862, etc.

Examples of dyes that do not themselves have a spectral sensitizing effect, or substances that do not substantially absorb visible light and exhibit supersensitization, are used with sensitizing dyes, such as aromatic organic acid formaldehyde condensates ( For example, U.S. Patent No. 3.
437,510), cadmium salts, azaindene compounds, aminostilbene compounds substituted with nitrogen-containing heterocyclic groups (e.g., U.S. Pat. No. 2,933,39)
No. 0, and those described in No. 3,635.721). U.S. Patent No. 3,615゜613, U.S. Patent No. 3,615,6
No. 41, No. 3.617.295, No. 3.635.72
The combinations described in No. 1 and others are particularly useful.

Antifoggants and stabilizers that can be used in the practice of the present invention include U.S. Pat. No. 2,713,541;
2,743. Pentazaindenes described in U.S. Pat. No. 2,743.181, U.S. Pat.
No. 062, No. 2,444,607, No. 2,444.6
No. 05, No. 2,756゜147, No. 2,835,58
No. 1, No. 2,852,375, Research Disclosure + - (Research Disclosure
), tetrazaindenes described in US Pat. No. 14851, triazaindenes described in U.S. Pat. ; thiazolium salts described in U.S. Pat. No. 2,131.038, U.S. Pat. No. 3,342.596, U.S. Pat. Quaternary onium salts such as phosphonium salts described in No. 50-40665; U.S. Patent No. 2.403
．． No. 927, No. 3.266.897, No. 3.708.
No. 303, JP-A-55-135835, JP-A No. 59-71
Mercaptotetrazoles, mercaptotetrazoles, mercaptodiazoles, mercaptothiazoles, described in U.S. Pat. mercaptobenzthiazoles, mercaptobenzimidazoles, mercaptooxadiazoles described in U.S. Pat. No. 2,843.491, U.S. Pat.
, 364.028; mercapto-substituted heterocyclic compounds such as mercaptothiadiazoles described in U.S. Pat. resorcinols described in Japanese Patent Publication No. 43-4133; polyhydroxybenzenes such as gallic acid esters described in Japanese Patent Publication No. 43-4133; tetrazoles described in West German Patent No. 1.189.380; 157,509, U.S. Patent No. 2.704.72
Penztriazoles described in U.S. Patent No. 1, U.S. Pat.
．． urazoles described in US Pat. No. 287.135, pyrazoles described in U.S. Pat. No. 3,106,467,
Indazoles described in U.S. Pat. pyrimidines, 3-pyrazolidones as described in U.S. Pat. No. 2,751,297, and heterocyclic compounds such as polymerized pyrrolidones or polyvinylpyrrolidones as described in U.S. Pat. No. 3,021,213. ; Japanese Patent Publication No. 54-13092
No. 9, No. 59-137945, No. 140445, British Patent No. 1,356,142, U.S. Patent No. 3.575
．． Various inhibitor precursors described in US Pat. No. 699, US Pat. No. 3,649,267, etc.; US Pat.
Sulfinic acid and sulfonic acid derivatives described in No. 3;
U.S. Patent No. 2.556.263, U.S. Patent No. 2,839.40
No. 5, No. 2゜488.709, No. 2,728,663
There are inorganic salts listed in this issue.

Gelatin is advantageously used as a binder (or protective colloid) for the silver halide emulsion of the present invention, but
Hydrophilic colloids such as synthetic hydrophilic polymer substances such as gelatin derivatives, graft polymers of gelatin and other polymers, other proteins, sugar derivatives, cellulose derivatives, and single or copolymers can also be used.

When gelatin is used as a binder for the silver halide emulsion of the present invention, the jelly strength of the gelatin is not limited, but it is preferably 250 g or more ((i) as measured by the baggy method).

The photographic emulsion layer or other hydrophilic colloid layer of a light-sensitive material using the silver halide emulsion of the present invention contains one or more hardeners that crosslink binder (or protective colloid) molecules and increase film strength. It can be used to harden the membrane. A hardening agent can be added to the processing solution to harden the photosensitive material to the extent that it is not necessary to add the hardening agent.
It is also possible to add a hardening agent to the processing solution.

A plasticizer can be added to the silver halide emulsion layer and/or other hydrophilic colloid layer of the silver halide photosensitive material of the present invention for the purpose of increasing flexibility.

The photographic emulsion layer and other hydrophilic colloid layers of the silver halide light-sensitive material of the present invention may contain a dispersion (latex) of a water-insoluble or poorly soluble synthetic polymer for the purpose of improving dimensional stability. can.

The silver halide emulsion layer of the present invention undergoes a coupling reaction with an oxidized form of an aromatic primary amine developer (for example, p-phenylenediamine derivatives, aminophenol derivatives, etc.) during color development to form a dye. Dye-forming couplers can be used. The dye-forming couplers are typically selected for each emulsion layer such that a dye is formed that absorbs light in the light-sensitive spectrum of the emulsion layer, with a yellow dye-forming coupler for the blue-sensitive emulsion layer and a dye for the green-sensitive emulsion layer. A magenta dye-forming coupler is used in the sensitive emulsion layer and a cyan dye-forming coupler is used in the red-sensitive emulsion layer. However, depending on the purpose, silver halide color photographic materials may be produced using different combinations from the above.

These dye-forming couplers preferably have a group called a ballast group in the molecule, which makes the coupler non-diffusive and has 8 or more carbon atoms. Furthermore, even if these dye-forming couplers are 4-equivalent, in which 4 molecules of silver ions need to be reduced in order to form 1 molecule of dye, only 2 molecules of silver ions need to be reduced. Either bi-isomerism is acceptable. Dye-forming couplers can be used as development accelerators, bleaching accelerators, developers, silver halide solvents, toning agents, hardeners, antifoggants, chemical sensitizers, etc. by coupling with oxidized forms of developing agents. Compounds that release photographically useful fragments, such as spectral sensitizers and desensitizers, can be included. Colored couplers that have a color correction effect on these dye-forming couplers, or DI that releases a development inhibitory side during development and improves image sharpness and image graininess.
An R coupler may also be used. In this case, it is preferable that the dye formed from the DIR coupler is of the same type as the dye formed from the dye-forming coupler used in the same emulsion layer, but if the color turbidity is not noticeable, a different type of dye may be used. It is also possible to use a DIR compound that is used in combination with a dye-forming agent and Minato Katsura to undergo a coupling reaction with an oxidized form of a developing agent to produce a colorless compound and at the same time release a development inhibitor.

DIR couplers and DIR compounds that can be used include those in which the inhibitor is directly bonded to the coupling position, and those in which the inhibitor is bonded to the coupling position via a divalent group, and the base circle released by the coupling reaction is These include those bound in such a way that the inhibitor is released by an intramolecular nucleophilic reaction, an intramolecular electron transfer reaction, etc. (referred to as timing DIR couplers and timing DIR compounds). Furthermore, inhibitors that are diffusible after release and those that are not so diffusible can be used alone or in combination depending on the purpose.

Although the coupling reaction is carried out with the oxidized product of the aromatic primary amine developer, colorless couplers that do not form dyes can also be used in combination with dye-forming couplers.

In the practice of the present invention, dye-forming couplers, colored couplers, DIR couplers, DIR
compounds, image stabilizers, color antifoggants, ultraviolet absorbers,
Among fluorescent brighteners, hydrophobic compounds can be prepared using various methods such as solid dispersion method, latex dispersion method, and oil-in-water emulsion dispersion method. It can be selected as appropriate.

Various methods for dispersing hydrophobic additives such as couplers can be applied to the oil-in-water emulsion dispersion method, and the boiling point is usually about 150.
A high boiling point organic solvent with a low boiling point and/or
Alternatively, dissolve it in combination with a water-soluble organic solvent, use a surfactant in a new aqueous binder such as an aqueous gelatin solution, and use a dispersion means such as a stirrer, homogenizer, colloid mill, flow jet mixer, or ultrasonic device. After emulsifying and dispersing it, it may be added to the desired hydrophilic colloid layer.

A step of removing the low boiling point organic solvent may be included simultaneously with the dispersion or dispersion.

/The ratio of high boiling point organic solvent and low boiling point organic solvent is 1:0. l
The ratio is preferably from 1:1 to 1:50, more preferably from 1:1 to 1:20.

In the practice of this invention, dye-forming couplers, DIR couplers, colored couplers, DIR compounds, image stabilizers,
When color antifoggants, ultraviolet absorbers, optical brighteners, etc. have acid groups such as carboxylic acid and sulfonic acid, they can also be introduced into the hydrophilic colloid as an alkaline aqueous solution.

Anionic surfactants, nonionic surfactants, Cationic surfactants can be used.

The oxidized form of the developing agent or the electron transfer agent may migrate between the emulsion layers (between the same color-sensitive layers and/or between different color-sensitive layers) of the silver halide photosensitive material of the present invention, causing color turbidity. A color anti-capri agent can be used to prevent sharpness from deteriorating and graininess from becoming noticeable.

The color antifoggant may be contained in the emulsion layer itself, or
An interlayer may be provided between adjacent emulsion layers and contained in the interlayer.

The silver halide photosensitive material of the present invention can contain an image stabilizer that prevents deterioration of dye images.

Hydrophilic colloid layers such as the protective layer and intermediate layer of the silver halide photosensitive material of the present invention are used to prevent fogging due to discharge caused by charging of the photosensitive material due to friction, etc., and to prevent image deterioration due to UV light. It may also contain an ultraviolet absorber.

In order to prevent deterioration of magenta dye-forming couplers and the like due to formalin during storage of the silver halide light-sensitive material of the present invention, a formalin scavenger may be used in the light-sensitive material of the present invention.

A development accelerator, a compound that changes the developability such as a development retardation side, and a bleach acceleration side can be added to the silver halide emulsion layer and/or other hydrophilic colloid layer of the silver halide photosensitive material of the present invention. Compounds that can be preferably used as development accelerators are listed in Research Disclosure.
Section XXI B of Disclosure No. 17463
- The compound described in Section D, and the development retardant is 17643
It is a compound described in Section XXI, Section E of No. A black and white developing agent and/or its precursor may be used to accelerate development or for other purposes.

The photographic emulsion layer of the silver halide photosensitive material of the present invention has a sensitivity of
Contains polyalkylene oxide or its derivatives such as ethers, esters, and amines, thioether compounds, thiomorpholines, quaternary ammonium compounds, urethane derivatives, urea derivatives, imidazole derivatives, etc. for the purpose of increasing contrast, increasing contrast, or accelerating development. But that's fine.

Supports used in the silver halide photosensitive material of the present invention include α-olefin polymers (e.g., polypropylene supports, semi-synthetic supports such as cellulose acetate, cellulose nitrate, polystyrene, polyvinyl chloride, polyethylene terephthalate, polycarbonate, polyamide, etc.), These include films made of synthetic polymers, flexible supports made of these films with reflective layers, glass, metals, ceramics, and the like.

In preparing the silver halide photosensitive material of the present invention, the silver halide emulsion layer and other protective colloid layers are prepared according to Research Disclosure.
17463, by the method described in XV, A, and dried by the method described in XV, No. 17463, B.

The silver halide photosensitive material of the present invention can be exposed to electromagnetic waves in a spectral region to which the emulsion layer constituting the photosensitive material of the present invention is sensitive. Light sources include natural light (sunlight), tungsten lamps, fluorescent lamps, mercury lamps, xenon arc lamps, carbon arc lamps, xenon flash lamps, cathode ray tube flying spots, various laser beams, light emitting diode lights, electron beams, X-rays, and T-rays. Any known light source can be used, such as light emitted from a phosphor excited by alpha rays or the like.

The exposure time is not only the 1 millisecond to 1 second exposure time normally used in cameras, but also the exposure shorter than 1 microsecond, for example, 100 nanoseconds to 1 microsecond exposure using a cathode ray tube or xenon flash lamp. However, exposures longer than 1 second are also possible.

The exposure may be performed continuously or intermittently.

Any method can be used for developing the silver halide photosensitive material of the present invention. This development process may be either a process for forming a silver image (black and white development process) or a process for forming a color image, depending on the purpose. If an image is created using the reversal method, a black-and-white negative development process is first performed, and then white exposure is applied or color development is performed by processing with a solution containing a fogging agent. Then, after exposure, a black and white development process is performed to create a silver image, and this can be used as a bleaching catalyst to bleach the dye.Silver dye bleaching may be used. A processing step is performed. In the case where a stop treatment step is performed after the development treatment step or a stabilization treatment step is performed after the fixation treatment step, the water washing treatment step may be omitted. Alternatively, the developing drug or its precursor may be incorporated into the sensitive material, and the developing process may be carried out using only an alkaline solution, or the developing process may be carried out using a Lith developer as the developing solution.

The color development process includes a color development process, a bleaching process, a fixing process, a water washing process if necessary, and/or
Alternatively, a stabilization process is performed, but instead of a process using a bleach solution and a process using a fixer, a bleach-fix process can be performed using a 1-solution bleach-fix solution, or a color development process can be performed. It is also possible to carry out a monobath processing step using a l-solution, development, bleach-fix processing solution in which bleaching and fixing can be carried out in lfa.

In combination with these processing steps, a pre-hardening process, its neutralization process, a stop-fixing process, a post-hardening process, etc. may be performed.In these processes, a color developing agent, or An activator treatment process may be performed in which the precursor is contained in the material and the development process is performed with an activator solution, or instead of monobath treatment, activator treatment, bleaching, and fixing treatments may be performed at the same time. Typical treatments during the processing are shown below. Processing process Constant fixation process/Color development process - Bleach-fix process/Pre-hardening process - Neutralization process - Color development process - Stop fixing process - Washing process - Bleach process Constant fixation process - Water washing process - Post-hardening process / Color development process - Water washing process - Supplementary color development process - Stopping process - Bleaching process Constant fixation process / Monobath process / Activator process - Bleach-fixing process - Activator treatment step - Bleaching treatment step Constant fixation treatment step [Examples of the invention] Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited by these.

Example 1 The following six types of solutions were prepared to prepare a monodisperse spherical seed emulsion.

E, 28% ammonia water 330ml IF
, 56% acetic acid 560m 114
At 0° C., solutions B and C were added to the stirred solution A1 by a double jet method. Addition speed at the beginning of addition is 35mj/min.11 At the end of addition, it is 80mj/min! It was gradually changed so that Furthermore, pBr was maintained at 1.1 during addition. The time required to complete the addition was 33 minutes.

After the addition was completed, washing with desalinated water was carried out using a conventional method.

The emulsion consisted of polydisperse grains that were mostly multiply twinned.

Next, maintain the temperature at 40°C, add solution to this emulsion, and add solution E.
1 was added and aged for 1 minute. At this time, the ammonia concentration was 0.89 mol/j! 5pBr was 0.5. Thereafter, solution F+ was immediately added to neutralize the solution, and washing with demineralized water was performed again using a conventional method.

The silver halide grains contained in this emulsion have an average grain size of 0.
The particles had a particle size of 32 μm and were monodisperse spherical particles.

This emulsion is called Em-1.

Next, using seed emulsion Em-1 and the four types of solutions shown below,
A core/shell type monodisperse emulsion was produced.

The amount of the seed emulsion corresponds to 8 mol % of the final silver halide.

That is, solutions Bm-1 and 03 were added to solution A8 kept at 40° C. and stirred by a double jet method to grow a silver iodobromide emulsion with a silver iodide content of 1000 mol%,
The addition was interrupted when the addition of solution B8-1 was completed.

At this time, 51% of the final silver halide was formed. p
After adjusting Br, the solution Bg-
2 and 02 were added to grow silver iodobromide with a silver iodide content of 1.0 mol %.

The pH and pBr during addition were controlled as shown in Table 1 by adding KBr solution and acetic acid solution.

The speed of addition liquid is also shown in the same way.

Table 1 After the addition was completed, the pH was adjusted to 6.00 using acetic acid, and the solution was washed with desalinated water using a conventional method. The emulsion obtained at this time is called Em-2. When Em-2 silver halide grains were observed using an electron microscope, the average aspect ratio was 4:1 and the average grain size was 0.70.
The manufacturing process will be explained.

In this step, before growing silver iodobromide containing 10.0 mol% silver iodide, an aqueous potassium iodide solution in the amount shown in Table 2 was added to the solution Am, and the mixture was aged for 10 minutes. Other than that, Em-3 to Em- were created using the same operations as Em-2.
5 was created. Furthermore, in place of the potassium iodide aqueous solution used in the production of Em-3 to Em-5, a silver iodide emulsion was added in the amount shown in Table 2 and ripened for 10 minutes.
-6 was created.

In addition, in the manufacturing process of Em-2, at the end of the growth of silver iodobromide containing 10.0 mol% silver iodide, an aqueous potassium iodide solution in the amount shown in Table 2 was added and the process was aged for 10 minutes. Em-7 to Em-10 were created by the same operation as Em-2.

14 1982-58237 (13) Emulsion samples prepared as above Em-2 to Em-1
0 was divided into silver halide contents equivalent to 0,635 mol, each was chemically sensitized using ammonium thiocyanate, sodium thiosulfate, and chloroauric acid, and anhydro-5, anhydro-5, and green-sensitizing dyes were added. 5'-dichloro-9-ethyl-3,3''-di(3-sulfopropyl)
Oxacarbocyanine hydroxide; anhydro-5,
51-diphenyl-9-ethyl-3,31-di(3-
sulfopropyl)oxacarbocyanine; anhydro-
9-ethyl-3,3″-di(3-sulfopropyl)-
Add 20 g each of 5,6,5',6'-dibenzoxacarbocyanine hydroxide, and then add 4-hydroxy-6-methyl-1,3゜3a, 7-titrazaindene and 5-phenyl-1-mercapto. Tetrazole was added. Next, 12% of the dispersion (M-1) with the following composition was added.
00.1, saponin and 1,2-bisvinylsulfonylethane were added and coated on a cellulose triacetate base support at a silver content of 15 mg/dnf, and dried to obtain a sample with a stable coating film. These samples were designated as samples 11m1 to 9 in Table 2.

Dispersion (M-1) as magenta coupler i (2,4,6-)dichlorophenyl)-3-(3-(2,4-diter t-amylphenoxyacetamide)-benzamide]-5-
Pyrazolone was used at 8×10-” mol per mol of silver halide, and 2-(1-phenyl-5
-tetrazolylthio)=4-octadecylsuccinimide=l-indanone per mol of halogenated ml
8 mol was used.

This was mixed with tricresyl phosphate in an amount of 1 times the weight of the coupler as a high-boiling organic cutting, and ethyl acetate was added to the mixture and heated to 60°C to completely dissolve it. Add this solution to 5% of a 10% aqueous solution of Alkanol B (registered trademark, alkylnaphthalene sulfonate manufactured by DuPont).
0-! and 700 mJ of 10% gelatin aqueous solution! and dispersed using a colloid mill.

These samples and comparative samples were exposed to green light for 8 seconds and 1/100 seconds using a KS-1 sensitometer (manufactured by Konishiroku Photo Industry Co., Ltd.) according to the JIS method, and then subjected to the following color development treatment. Ta. Then, fog, sensitivity at 8 second exposure, and sensitivity at 1/100 second exposure were determined. The results are shown in Table-2.

(Processing process) (37.8°C) Processing time 1,
Color development 3 minutes 15 seconds 2, bleaching 6 minutes 30 seconds 3, washing with water
3 minutes 15 seconds 4, fixed
6 minutes 30 seconds 5, wash with water 3
minute 15 seconds 6, stabilization 1 minute 30 seconds 7,
Drying [Color developing solution composition] [Bleaching solution composition] [Fixer composition] [Stabilizing solution composition] Separately, sample groups 1 to 9 were dried at 65°C and 10% R, H.
.

After forced deterioration for 3 days, the color development process described above was carried out, and the change in fog over time (thermal fog stability) was measured. The measurement results at this time are also shown in Table-2.

From the results in Table 2, photographic materials using the silver halide emulsion of the present invention (sample &3.11m4. Na5, N
a7. m8) shows a remarkable improvement in the decrease in sensitivity during long-time exposure, and also shows a remarkable improvement in the fluctuation of fog in the forced deterioration test.

Example 2 Seed grains containing multiple twins having a silver iodide content of 6.5 mol % were prepared using the following three solutions according to the method disclosed in Japanese Patent Application Laid-open No. 142329/1983.

CsO,45MAgN Ox
Solution B was added to the stirred solution A at 1350 cc at 40°C at a rate of 35 cc/min, and after a 30 second delay, solution C+1 was added at 65/min for 20 minutes each. After the addition was completed, washing with desalinated water was carried out using a conventional method. This emulsion is called Em-11.

This emulsion contains multiply twinned grains, quasi-twinned grains and octahedral grains, the proportion of multiply twinned emulsions is about 30%, and the average grain size is 0.
．． The variation coefficient of the 278ml particle size distribution was 32%.

Next, a monodisperse emulsion having a silver iodide content of 4.2 mol % was prepared using the seed emulsion Em-11 and the three types of solutions shown below.

The amount of seed emulsion corresponds to 7.1 mol% of the final silver halide.

A silver iodobromide emulsion having a silver iodide content of 4.2 mol % was grown by adding solution El and solution F3 to the solution stirred at 40° C. using a double jet method, and forming solution E, The addition was interrupted when the addition of F and F was completed. The pH and pBr during addition were controlled as shown in Table 3 by adding KBr solution and acetic acid solution.

In addition, the addition rate of the additive liquid is also shown in the same table, but p
The Br and addition rate were determined with reference to the conventional method disclosed in JP-A-55-142329.

Table 3 After the addition was completed, the pH was adjusted to 6.00 using acetic acid, and demineralized water washing was performed using a conventional method. The resulting emulsion is called Em-12. When silver halide grains of Em-12 were observed using an electron microscope, the average aspect ratio was 3:1, the average grain size was 0.77 μm, and halogen contained within a grain size range of ±20% around the average grain size of 7. A monodispersed emulsion having a silver oxide weight of 64% and containing 38% twin grains was obtained.

Next, in the manufacturing process of Em-12, Em-1
Em-13 to Em-16 were prepared by the same operation as in Example 2.

Furthermore, Em-12 was further processed using Em-12, except that the potassium iodide aqueous solution of Em-13 to Em-16 was replaced with a silver iodide emulsion in the amount shown in Table 4, and ripening was performed for 10 minutes.
17 to Em-18 were created.

In addition, in the manufacturing process of Em-12, when 80 mol% of silver halide was formed based on the final amount of silver halide, an aqueous potassium iodide solution in the amount shown in Table 3 was added and ripened for 10 minutes. Em-19 was created using the same operations as Em-12, except for the following.

Using the emulsions Em-12 to Em-19 thus obtained, these emulsions were respectively coated on a support in the same manner as in Example 1 to prepare samples 10 to 17 in Table 4. Sensitometric evaluation was performed by the same method as in Example 1. The measurement results are shown in Table-4.

As can be seen from the measurement results in Table 4, the photographic material of the present invention shows a remarkable improvement in the decrease in sensitivity during long-time exposure, and also shows a remarkable improvement in the change in capri in the forced deterioration test.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to produce a silver halide emulsion with high sensitivity, improved low-illuminance reciprocity law failure characteristics, and improved fogging characteristics over time. All of the silver halide photographic materials have the excellent performance described above.

Patent applicant: Konishiroku Photo Industry Co., Ltd., agent patent attorney
Toru Takatsuki Procedural Amendment (December 4, 1988, Director General of the Patent Office, Michibe Uga, 1, Indication of the Case, 1985, Patent Application No. 198324, 2, Title of Invention: Silver halide emulsion and method for producing the same) and Silver halide photosensitive material 3 using said silver halide emulsion, relationship with the case of the person making the amendment Patent applicant address: 1-26-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Name
(127) Roku Konishi Photo Industry Co., Ltd. 4, Agent 6, page 5, lines 7-10 of the statement of contents of the amendment [In this case... is not preferred]. ' shall be amended as follows.

Claims (1)

[Scope of Claims] 1. Multi-twin particles and/or spherical particles obtained from multi-twins are grown as seed particles, and 5 to 95 mol% of the total particles are grown.
At any point during the formation of 0.0% of the total silver halide.
1. A silver halide emulsion comprising silver halide grains having an average aspect ratio of less than 5:1 and containing 0.005 to 20 mol % of silver iodide substituted with halogen by iodide. 2. Multi-twin particles and/or spherical particles obtained from multi-twins are grown as seed particles, and 5 to 95 mol% of the total particles
At any point during the formation of 0.0% of the total silver halide.
A method for producing a silver halide emulsion, characterized by carrying out halogen substitution with 005 to 20 mol % of iodide. 3. Multi-twin particles and/or spherical particles obtained from multi-twins are grown as seed particles, and 5 to 95 mol% of the total particles
0.00 of the total silver halide is formed at any time
A silver halide photosensitive material comprising a silver halide emulsion containing silver halide grains having an aspect ratio of less than 5:1 and containing 5 to 20 mol % of silver iodide substituted with halogen by iodide.