JPS62187339A - Silver halide photographic sensitive material - Google Patents

Abstract

PURPOSE:To maintain stable photographic characteristics during the preservation with lapse of time by incorporating >=1 layers of emulsion layers contg. silver halide particles consisting of dodecahedral crystals of which the surface is a (110) face and >=1 specific compds. having specific structure. CONSTITUTION:At least >=1 layers of the silver halide emulsion layers contg. the silver halide particles consisting of the dodecahedron crystals of which the surface is the Miller index (110) face and at least >=1 compds. expressed by the formula is incorporated into the photosensitive material. The (100), (111) faces etc. may exist on the surface of the particles and the ratio of the (110) face to the total surface area of the particles is preferably >=20%. The particles having the (110) face are preferably incorporated at >=30wt% in the silver halide emulsion. The compd. expressed by the formula is added in a 0.1-1,000mg range per mol of the silver halide. The photosensitive material contg. a fogging restrainer which has the lower possibility of causing the decrease of the sensitivity and the softening of gradation based on the development restraining is thus obtd.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a silver halide photographic light-sensitive material, and particularly to a highly sensitive 7% silver lodenide photographic light-sensitive material in which deterioration in sensitivity and occurrence of fog during storage over time are prevented.

[Conventional technology]

Silver halide photographic light-sensitive materials (hereinafter referred to as "light-sensitive materials") tend to cause blemish due to the presence of nuclei that can be developed even without exposure, and sensitivity decreases especially due to the generation of capri during storage over time. , or deterioration of gradation is extremely common. Since it is desirable to minimize such undesirable phenomena, it has been known to add antifoggants, stabilizers, etc. to silver halide emulsions. For example, U.S. Patent No. 2,403°927;
4. (1-phenyl-5-mercaptotetrazoles described in No. +33, Japanese Patent Publication No. 39-2825, etc., or 4
-Hydroxy-6-methyl-1,3°38.7-tetrazaindene and the like have been used as fog suppressants. In recent years, there has been remarkable progress in photosensitive materials, especially photosensitive materials, such as higher sensitivity represented by ASA 1600 color negative film, and smaller 70m format represented by disk film. As a result, there is an increasing demand for high-sensitivity technology that maintains high image quality and high resolution. This requirement applies not only to color light-sensitive materials but also to white:A light-sensitive materials for R-photography, including X-ray light-sensitive materials. Conventionally, many techniques have been developed to obtain high-sensitivity silver halide emulsions.
A monodisperse system that aims to improve quantum efficiency and obtain high sensitivity while maintaining low capri, as seen in Taiyo No. 60-222842.
There are silver halide emulsions made of dodecahedral silver halide particles having (110) planes, which are said to have good metal sensitizing effects. Among these, photosensitive materials using dodecahedral silver halide grains have the characteristics of high sensitivity and low fogging immediately after production, but the stability of photographic properties during storage over time is not guaranteed. However, it has the disadvantage that fogging is large, especially when stored at high temperatures. The biggest obstacle in increasing the sensitivity of photosensitive materials is the occurrence of fog in silver halide emulsions, and as mentioned above, technology to suppress fog during storage over time holds the key to producing highly sensitive photosensitive materials. I can say it. Fogging suppression techniques include mercapto-7zoles represented by the above-mentioned 1-phenyl-5-mercaptotetrazole, and hydroxyboriazoles represented by 4-hydroxy-6-methyl 1.3,3a,7-tetrazaindene. In addition to indenes, the two described in U.S. Pat. No. 2.131.038
-Mercaptopenzothi7zoles or Vf 1988
Methods for suppressing fog in high-sensitivity photosensitive materials using benzothiazoline derivatives disclosed in No. 194029 are known, but all of them have insufficient suppressive power and are unsatisfactory, especially for storage under high-temperature conditions and high-temperature rapid processing. This is the current situation.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and its first object is to provide a highly sensitive photographic material containing a fog suppressant that can maintain stable photographic properties during storage of the photographic material over time. It is to be. A second object of the present invention is to provide a photosensitive material containing a capri inhibitor that is less likely to cause a decrease in sensitivity or softening of gradation due to development inhibition. A third object is to provide a photosensitive material in which the occurrence of fog is significantly suppressed when subjected to high-temperature development, particularly at 30° C. or higher.

Structure 1 of the Invention The above object of the present invention is to provide at least one silver halide emulsion layer containing dodecahedral crystal silver halide grains having a (110) surface, and a silver halide emulsion layer represented by the following general formula (r). This is achieved by a photosensitive material containing at least one of the compounds. Hereinafter, the remainder d general formula (13% formula%, where Z is a heterocyclic ring having directly or indirectly at least one group selected from -3O, M'', -COOR', -OH and -NHR') , Ml and M2 each represent a hydrogen atom, an alkali metal or a -NH group, R1 represents a hydrogen atom, an alkali metal or an alkyl group having 1 to 6 carbon atoms, and R2 represents a hydrogen atom or a C1 to C6 alkyl group. 6 represents an alkyl group, -COR, -COOR, or -8O2R', and R represents a hydrogen atom, an aliphatic group group, or a Banko group group.Hereinafter, the present invention will be described in more detail. The silver halide grains according to the present invention have a Miller index (110
) The surface of the 0 particle, which is a dodecahedral crystal with a crystal plane defined by
(111) planes etc. may be present, but the ratio of (110) planes to the total surface area of the particle is preferably 20% or more, particularly preferably 80% or more νt. Further, the presence of the (110) plane and its proportion can be determined by a method using an electron microscope or a dye adsorption method. In the silver halide emulsion of the present invention, the silver halide grains having (110) planes preferably account for 30% by weight or more, more preferably 50% by weight or more. The halogen composition of the silver halide grains according to the present invention is not particularly limited, but silver bromide or silver iodobromide is preferably used. There are no particular restrictions on the particle size of the silver halide grains, and the present invention is preferably at least effective within the range of 0.1 to 3.0 micron particles. In the present invention, the grain size of silver halide grains is expressed by the length of one side of a cube equal to its volume. The silver halide grains according to the present invention are usually produced and used in a form dispersed in a dispersion medium such as gelatin, that is, in a form called an emulsion. The particle size distribution of the group of particles at this time may be monodisperse, polydisperse, or a mixture of these, and can be appropriately selected depending on the purpose and the like. To prepare silver halide grains having (110) planes according to the present invention, the method disclosed in Japanese Patent Application Laid-Open No. 60-222842 or Japanese Patent Application No. 59-158111 can be used. That is, in JP-A No. 30-222842, in an aqueous medium in which a hydrophilic protective colloid and a mercaptoazole neck that promotes the development of (110) crystal faces coexist, (110)
The preparation of silver halide emulsions consisting essentially of silver bromide or silver iodobromide having a surface is disclosed. On the other hand, Japanese Patent Application No. 59-158111 describes a method for producing silver bromide or silver iodobromide grains having (110) planes, in which a step of forming silver halide grains in the presence of a protective colloid, It has been shown to control the pAg of the emulsion in the range of 8.0 to 9.5 while producing at least 30 mole percent of the total silver halide, and to include hydroxyboriazaindenes as crystal control compounds. . Next, regarding the compound of the present invention represented by general formula (r),
explain. Z in the general formula (1) is -8O, M2, -COO
It represents a heterocyclic residue in which at least one selected from RI, -OH and -NHR2 is bonded directly or indirectly, and specifically, for example, an oxazole ring, a thiazole ring, an imidazole ring, a selenazole ring, a triazole ring. , tetrazole ring, thianoazole ring, oxadiazole ring, bentazole ring, biriminone ring, thianone ring, trianone ring, thiocyanone ring, etc., or rings bonded to other carbocycles or heterocycles, such as benzothiazole ring, benzotriazole ring, Examples include a benzimidazole ring, a benzoxazole ring, a benzoselenazole ring, a naphthoxazole ring, a triazaindolinone ring, a diazaindolinone ring, and a tetraazaindolinone ring. Preferred examples include an imidazole ring, a tetrazole ring, a benzimidazole ring, a benzoselenazole ring, a benzothiazole ring, a benzoxazole ring, and a triazole ring. Particularly preferred are a tetrazole ring and a triazole ring. However, M2 is a hydrogen atom, an alkali metal or -NH,
R1 represents a hydrogen atom, an alkali metal or an alkyl group having 1 to 6 carbon atoms, and R2 represents a hydrogen atom or a C1-C6 alkyl group.
~6 alkyl group, -CoR3, -COORco or -8o2Rco, and R3 represents a hydrogen atom, an aliphatic group or an aromatic group. The aliphatic group and aromatic group represented by R2 may have a substituent, and Ml represents a group having the same meaning as M2. Preferred specific examples of the compound (1) according to the present invention are described below, but the present invention is not limited thereto as a matter of course. (+-5) (+-6)(1
-7) (+-8) (1-9
) (1-1o)< + -U
) ■ (+-19) (] -40) (T -49) (+ -50
) “\Nii゛\N/” N11゜(+ -55) (1-56)
N11゜(1-59) (+ -60)
(1-65) (I-66)
(I-69) (1-70)
n Examples of methods for synthesizing the compound represented by the above general formula CI) include US Patent No. 3,266.897, British Patent No. 1275701, or R.C.
K.D. Dubenko (R.G. Dubenko, V. D. Panche
nko) r kim detev otsuiki sodin sp.
Khim. Getevotsiki 5oedin, Sb −
1: Azots, odev. Z haschie G eterotsiky)1
99-201 (1967), Kay Hotman (K,
Hots+ann)rThe Chemistry Op Heterocyclic Compound
*1st try ofHetero cyclic
cos+pounds, I widazole a
ndIts D eriveatives) Published by Interscience
t-1, 384 (1953), etc. may be followed. The amount of the compound of the present invention added is equivalent to 1 mole of silver halide)
It is preferably used in a range of 0.1 to 1000 mg, more preferably 0.5 to 800 mg. Further, in the case of a silver halide emulsion, it is added during chemical ripening, after chemical ripening, and/or immediately before coating the emulsion, but it is more preferably added at the end of chemical ripening of the silver halide emulsion. Known anti-capri agents or stabilizers other than those of the present invention may also be used as long as they do not impede the effects of the present invention. Anti-capri agents or stabilizers that can be used include:
For example, hepazoles include benzothiazole, nitrointazole, benzotriazole, nido-a-penciimiguzole, etc., or furcapto-substituted heterocyclic compounds outside the present invention include mercaptobenzothiazole,
Mercaptobenzimidazole, mercaptobenzoxazole, norcaptooxanoazole, mercaptothi7no7zole, mercap))su7zole, mercaptotri7non, mercaptotetrazole j! l[(wait 1-
phenyl-5-mercaptotetrazole), and also azaindenes, such as 4-hydroquine-1°3.3m, ?
- Capri inhibitors or stabilizers well known in the art, such as tetrazaindene, can be used in combination. The photosensitive material of the present invention can be applied to the following various types of photosensitive materials. For example, for general black and white, for X-ray recording, for plate making, for color positive, for color negative, for color paper, for color printing,
Although it can be used in photosensitive materials for direct printing and thermal development, it is advantageous to apply it to color photosensitive materials with a multi-N structure. In the silver halide emulsion of the present invention, silver bromide and silver iodobromide are preferably used as silver halides, but in addition to silver halide, silver halides such as silver iodochloride, silver chlorobromide, and silver chloride are used. Any used in emulsions can be used. The silver halide grains used in the halogenated ffi emulsion may be obtained by any of the acid method, neutral method, and ammonia method. The particles may be grown all at once, or may be grown after forming seed particles! The method of creating and growing the 11 particles may be the same or different. Silver halide emulsions can be prepared by mixing halide ions and silver ions at the same time, or by mixing one in a solution where the other is present. , halide ions and vibration ions may be generated by sequentially and simultaneously adding them while controlling the pH and/or l)Ag in the mixing pot. By this method, silver halide grains having a regular crystal shape and a nearly uniform grain size can be obtained. After growth, the halogen composition of the particles may be changed using the Humbage encrusting method. Silver halide emulsions are manufactured by using a silver halide solvent as necessary to adjust the grain size of silver halide grains.
Be able to control particle shape, particle size distribution, and particle growth rate. Silver halide grains are produced in the process of forming and/or growing grains by forming cadmium salts, zinc salts, lead salts, thallium salts, iridium salts (including complex salts), rhodium salts (including complex salts), and iron salts ( (including complex salts) to add metal ions to the inside of the particles and/or
Alternatively, these metal elements can be contained on the particle surface, and reduction sensitizing nuclei can be provided inside the particle and/or on the particle surface by placing the particle in an appropriate reducing atmosphere. Unnecessary soluble salts may be removed from the silver halide emulsion after the growth of silver halide grains is completed, or they may be left contained. When removing the salts, use Research Disclosure (Research Disclosure).
Closure (hereinafter abbreviated as RD)) No. 17643, Section (2) may be used. The silver halide grains may have a uniform silver halide composition distribution within the grain, or may be core/shell grains in which the silver halide composition differs between the inside of the grain and the surface layer. The silver halide grains may be such that the latent image is mainly formed on the surface, or may be such that the latent image is mainly formed inside the grain. Silver halide emulsions may have any grain size distribution. Emulsions with a wide grain size distribution (referred to as polydisperse emulsions) may be used, or emulsions with a narrow grain size distribution (monodisperse emulsions) may be used. The monodisperse emulsion referred to here refers to one in which the standard deviation of the grain size distribution divided by the average grain size is 0.20 or less, where the grain size is spherical halogenated emulsion. In the case of silver, the diameter is shown; in the case of particles with a shape other than spherical, the diameter when the projected image is converted to a circular image of the same area) may be used alone or in combination of several types. An emulsion and a monodisperse emulsion may be mixed and used. The silver halide emulsion may be a mixture of two or more separately formed silver halide emulsions. Silver halide emulsions can be chemically sensitized by conventional methods. That is, sulfur sensitization method, selenium sensitization method, reduction sensitization method,
A noble metal sensitization method using gold or other noble metal compounds can be used alone or in combination. Silver halide emulsions can be optically sensitized to a desired wavelength range using dyes known in the photographic industry as sensitizing dyes. The sensitizing dye may be used alone or in combination of two or more, and together with the sensitizing dye, it may be a dye that itself does not have a spectral sensitizing effect, or a compound that does not substantially absorb visible light. In addition, a supersensitizer that enhances the sensitizing action of the sensitizing dye may be included in the emulsion. Sensitizing dyes include cyanine dyes, merocyanine dyes,
Complex cyanine dyes, complex 70 cyanine dyes, holopolar cyanine dyes, hemicyanine dyes, steryl dyes and hemioxal 71 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, pyridine nucleus, oxazoline nucleus, thiazoline nucleus, pyrrole nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus, imidazole nucleus, tetrazole nucleus, pyridine nucleus, and the 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, penzimiguzole nucleus, and quinoline nucleus. These nuclei may be substituted on carbon atoms. Merocyanine dyes or complex merocyanine dyes include a pyrazolin-5-one nucleus, a thiohyguntoin nucleus, and a 2-thioxazolidine-2 nucleus having a ketomethylene structure.
, 4-noone nucleus, thiazolinone-2,4-noone nucleus, logenine nucleus, thiobarbic acid nucleus, etc., can be applied. Examples of useful sensitizing dyes used in blue-sensitive silver halide emulsion layers include West German Patent No. 929.080, US Pat. No. 2,231,658, US Pat. 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 1
, No. 242,588, Special Publication No. 44-14031t, No. 5
2-24844, etc. I will end by listing the following. Further, useful sensitizing dyes used in green-sensitive silver halide emulsions include, for example, U.S. Pat.
．． No. 201, No. 2.072, 908, No. 2.739,
No. 149, No. 2,945,76:1, U.S. Patent No. 505
Typical examples thereof include cyanine dyes, merocyanine dyes, and composite cyanine dyes such as those described in , No. 979, etc. Furthermore, useful sensitizing dyes used in red-sensitive silver halide emulsions include, for example, U.S. Pat.
No. 78, No. 2,442,710, No. 2,454,62
Typical examples thereof include cyanine dyes, merocyanine dyes, and composite cyanine dyes as described in No. 9 and No. 2776.280. Furthermore, U.S. Patent Nos. 2,213,995 and 2,493,7
No. 48, No. 2゜519.001, West German Patent No. 929,0
The final cyanine dyes, merocyanine dyes, or composite cyanine dyes described in No. 80 and the like 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, and combinations of sensitizing dyes are often used particularly for the purpose of supersensitization. Typical examples are Special Publications No. 43-4932, No. 43-4933, No. 43
-4936, 44-32753, 45-258
No. 31, No. 45-28474, No. 46-11627, No. 46-18107, No. 47-8741, No. 47
-11114, 4fu No. 25379, 47-37
No. 443, No. 48-28293, No. 48-38406
No. 48-38407, No. 48-38408, No. 48-41203, No. 48-41204, No. 49-
No. 8207, 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. 54-80118, No. 56-25728, No. 57-1438, No. 58-10753, No. 58-91
No. 445, No. 58-153928, No. 59-1145
No. 33, No. 59-116645, No. 59-11664
No. 7, U.S. Pat. No. 2,688.545, U.S. Pat. No. 2,977.
No. 229, No. 3,397,060, No. 3,506,4
No. 43, No. 3,578,447, No. 3,672,89
No. 8, No. 3 = 679,428, No. 3,769,301
No. 3,814,609, and No. 3,837,862. 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 am formaldehyde condensates ( For example, U.S. Patent 3,
473,510); cadmium salts; azaindene compounds;
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 are particularly useful. Silver halide emulsions are used during the manufacturing process of photosensitive materials, during storage,
Alternatively, for the purpose of preventing fog during photographic processing or maintaining stable photographic performance, photographic Compounds known in the industry as anti-capri or stabilizers can be added. As anti-capri agents and stabilizers, US Patent No. 2.713,
No. 541, No. 2,743,180, No. 2,743,1
Pentazaindenes described in No. 81, U.S. Patent No. 2
, 716°062, 2,444,607, 2,
No. 444,605, No. 2,756゜147, No. 2,8
No. 35,581, No. 2,852,375, RD148
Tetrazaindenes described in No. 51, U.S. Patent No. 2,
772,164 and 7zaindenes such as polymerized azaindene M described in JP-A-57-211142; U.S. Patent No. 2,13
No. 1,038, No. 3,342,596, No. 3,954
, 478, U.S. Pat.
Quaternary onium salts such as biryllium salts described in No. 148゜067 and phosphonium salts described in Japanese Patent Publication No. 50-40885; Catechols, resorcinols described in Japanese Patent Publication No. 5e-44413, and polyhydroxybenzenes such as gallic acid esters described in Japanese Patent Publication No. 43-4133; West German Patent No. 1,189
, 380, U.S. Patent No. 3,
157,509; benzotriazoles described in U.S. Pat. No. 2g704.721; urazoles described in U.S. Pat. No. 3,287,135; The pyrazoles described in U.S. Pat. No. 2,271,229 rX
Indazole and V + ¥ 1111 1982
-No.90844! : Notee % jt ta;t: ')
Azoles such as v-benzotriazole M, pyriminones described in U.S. Pat. No. 3,161.515,
Heterocyclic compounds such as 3-pyrazolidones described in U.S. Pat. No. 2,751,297 and polymerized pyrrolidones or polyvinylpyrrolidones described in U.S. Pat. No. 3,021,213; No. 130929,
No. 59-137945, No. 140445, British Patent No. 1,356,124, National Patent No. 3, 575
, No. 699, No. 3,649.267, etc.; U.S. Pat. No. 3,047°393
Sulfinic acids and sulfonic acid derivatives described in US Pat. No. 2,556,263, US Pat. No. 2,839,405, US Pat. There are salt necks etc. It is advantageous to use gelatin as a binder (or protective colloid) for silver halide emulsions, but gelatin derivatives, graft polymers of gelatin and other polymers, other proteins, sugar derivatives, cellulose derivatives, single Or now like a copolymer! & Hydrophilic colloids such as hydrophilic polymeric substances can also be used. The photographic emulsion layer and other hydrophilic colloid layers of the light-sensitive material of the present invention are hardened by using one or more hardeners that crosslink binder (or colloid) molecules and increase film strength. be able to. Hardener is at 8! Although it is possible to add an amount of the light-sensitive material capable of hardening to such an extent that it is not necessary to add a hardening agent to the processing solution, it is also possible to add a hardening agent to the processing solution. A plasticizer can be added to the silver helodenide emulsion layer and/or other hydrophilic colloid layer of the light-sensitive material for the purpose of increasing flexibility. Preferred plastic wastes are the compounds described in section 1A of RD 17643. The photographic emulsion layer and other hydrophilic colloid layers of the light-sensitive material may contain a dispersion (latex) of a water-insoluble or sparingly soluble synthetic polymer for the purpose of improving dimensional stability. The emulsion layer of the light-sensitive material contains a dye that forms a dye through a coupling reaction with an oxidized form of an aromatic primary amine developer (for example, l)-phenylenediamine derivative, aminophenol derivative, etc.) during color development processing. Forming couplers are 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. It is desirable that these dye-forming couplers have a group called a ballast group in the molecule, which makes the coupler non-diffusive and has 8 or more carbon atoms. Either 4-isomerism, in which 100 silver ions need to be reduced, or 2-isomerism, in which only 2 molecules of silver ions need to be reduced, may be used. Dye-forming couplers can be used as development inhibitors, development accelerators, bleach accelerators, developers,
Included are compounds that release seven photographically useful fragments such as silver halide solvents, toning agents, hardeners, fogging agents, antifoggants, chemical sensitizers, spectral sensitization M1 and desensitization. Ru. Among these, couplers that release a development inhibitor during development and improve image sharpness and image graininess are called DIR couplers. In place of the DIR coupler, a DIR compound which undergoes a coupling reaction with the oxidized form of the developing agent to produce a colorless compound and at the same time releases a development inhibitor may be used. DII used? Couplers and DIR compounds include those in which an 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 molecule in the makuuchi that is released from l# by the coupling reaction. These include those in which the inhibitor is bonded so as to be released by an internal nucleophilic reaction, an intramolecular electron transfer reaction, etc. (referred to as a timing DIR coupler and a timing DIR compound). Moreover, the inhibitor can be used either alone or in combination, depending on the purpose, depending on the purpose, one that is diffusible after release and one that is less diffusible. A colorless coupler (also called a competitive coupler) which undergoes a coupling reaction with an oxidized aromatic primary amine developer but does not form a dye can also be used in combination with a dye-forming coupler. As the yellow dye-forming coupler, known acylaceto-7nylide couplers can be preferably used. Among these, benzoylacetanilide and pivaloyl 7cetanilide compounds are advantageous. As magenta dye-forming couplers, 5-virazolone couplers, pyrazolobenzimidazole couplers, open-chain acylacetonitrile couplers, indashilon couplers, etc. other than those of the present invention may be used together with the couplers of the present invention. As cyan dye-forming couplers, 7-enol or 7-tole couplers are generally used. Among dye-forming couplers, DIR couplers, DIR compounds, image stabilizers, various pre-preventing agents, ultraviolet absorbers, optical brighteners, etc. that do not need to be attached to the surface of silver halide crystals, hydrophobic compounds can be prepared using the solid dispersion method. Dispersion can be carried out using various methods such as latex dispersion method, oil-in-water emulsion dispersion method, etc., and this can be appropriately selected depending on the chemical structure of the hydrophobic compound such as the coupler. The oil-in-water emulsion dispersion method can be applied to conventionally known methods for dispersing hydrophobic additives such as couplers, and is usually mixed with a high-boiling organic solvent having a boiling point of about 150°C or higher and, if necessary, a low-boiling point and/or a high-boiling point organic solvent. Alternatively, it can be dissolved using a water-soluble organic solvent and a surfactant in a hydrophilic binder such as an aqueous gelatin solution using a stirrer, homogenizer, colloid mill, 70-kn mixer, JIt.
After emulsification and dispersion using a dispersion means such as an f-wave device, a step of removing the low boiling point organic solvent may be added after or simultaneously with the zero dispersion, which can be added to the desired hydrophilic colloid liquid. High boiling, boiling point of phenol derivatives, 7-tar acid alkyl esters, phosphoric acid esters, citric acid esters, benzoic acid esters, alkylamides, fatty acid esters, trimesic acid esters, etc. that do not react with the oxidized form of the developing agent when used as an α solvent with a boiling point of 150°C The above organic solvents are used. Low boiling or water-soluble organic solvents can be used in conjunction with or in place of high boiling solvents. Organic solvents that are substantially insoluble in water (low boiling point) 3 include ethyl acetate, propyl acetate, butyl acetate, butyl acetate, chloroform, carbon tetrachloride, nitromethane, nitroethane, benzene, etc. Examples of solvents include acetone, methyl imbutyl ketone, β-ethoxyethyl acetate, methoxy glycol acetate, methanol, ethanol, acetonitrile, nooxane, dimethylformamide sulfuric triamide, diethylene glycol monophenyl ether, 7-ethyloxyethanol, etc. Can you name it? When dye-forming couplers, DIR couplers, DIR compounds, image stabilizers, color anti-capri agents, ultraviolet absorbers, optical brighteners, etc. have acid groups such as carboxylic acid or sulfonic acid, hydrophilic colloids can be used as alkaline aqueous solutions. You can also introduce it inside. When a hydrophobic compound is dissolved in a low boiling point solvent alone or in combination with a high boiling point solvent and dispersed in water using mechanical or ultrasonic waves, an anionic surfactant may be used as a dispersion aid.
Ionic surfactants, cationic surfactants and amphoteric surfactants can be used. The oxidized form of the developing agent or the electron transfer agent may migrate between the emulsion layers of the light-sensitive material (between the same color-sensitive layers and/or between different color-sensitive layers), causing color turbidity or deterioration of sharpness. An anti-color fog side can be used to prevent 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. An image stabilizer that prevents deterioration of dye images can be used in the light-sensitive material using the silver halide emulsion of the present invention. Examples of image stabilizers include 7-el derivatives and their bis forms, hydroxycoumaran and its spiro forms, hydroxychroman and its spiro forms, piperidine derivatives, aromatic amine compounds, benzodioxane derivatives, benzodioxane derivatives, and silicone. Atom-containing compounds, thioether compounds, etc. are preferred; specific examples thereof include British Patent No. 1.
, 410゜846, JP-A-49-134326, JP-A-52-35633, JP-A-52-147434, JP-A-52
-150630, 54-145530, 55-
No. 6321, No. 55-21004, No. 55-1241
No. 41, No. 59-3432, No. 59-5246, No. 59-10539, Special Publication No. 48-31625, No. 4
No. 9-20973, No. 49-20974, No. 50-2
No. 3813, No. 52-27534, U.S. Pat.
No. 18,613, No. 2,710,801, No. 2,73
No. 5.765, No. 2,816,028, No. 3,069
, No. 262, No. 3,336.135, No. 3,432,
No. 300, No. 3,457,079, No. 3,573,0
No. 50, No. 3,574,627, No. 3,698,90
No. 9, No. 3,700,455, No. 3,764.337
No. 3,935,016, No. 3,982,944, No. 4,013,701, No. 4,113.495,
4,120,723, 4,155.765, 4,159.910, 4,254,216, 4
, No. 268,593, No. 4,279,990, No. 4,
No. 332,886, No. 4,360,589, No. 4,4
No. 30,425, No. 4,452,884, and the like. The hydrophilic colloid layers such as the protective layer and intermediate layer of the photosensitive material of the present invention contain an ultraviolet absorber in order 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. May contain. In order to prevent deterioration of magenta dye-forming couplers and the like due to formalin during storage of the light-sensitive material, a formalin scavenger can be used in the light-sensitive material. When containing dyes, ultraviolet absorbers, etc. in the hydrophilic colloid layer of a photosensitive material, they may be mordanted with a mordant such as a cationic polymer. Compounds that change the developability, such as development accelerators and development retardants, and bleaching accelerators can be added to the silver halide emulsion layer and/or the hydrophilic colloid layer of the photosensitive material. A compound that can be preferably used as a development accelerator is R0176.
The compound is a compound described in Section XXI, B-0 of No. 43, and the development retardant is a compound described in Section XX[)'iE of No. 17643. A black and white developing agent and/or its precursor may be used to accelerate development or for other purposes. The emulsion layer of a light-sensitive material is made of polyalkyleneoxy l' or 1! for the purpose of increasing sensitivity, increasing contrast, or promoting development.
It may also include derivatives of their ethers, esters, amines, etc., thioether compounds, thiomorpholines, quaternary ammonium compounds, urethane derivatives, urea derivatives, imiguzole derivatives, and the like. Fluorescent whitening can be used in photosensitive materials for the purpose of emphasizing the whiteness of the white background and making the coloration of the white background less noticeable. Compounds that are preferably used as fluorescent sensitizers are described in Section 7 of RD17643. The photosensitive material may be provided with auxiliary layers such as a filter layer, a haleysilane prevention layer, and an irradiation prevention layer. These layers and/or the flower layer may contain dyes that are washed out of the light-sensitive material or bleached during the development process. Examples of such dyes include oxo-7-l dyes, hemioxol-7-l dyes, styryl dyes, merocyanine dyes, cyanine dyes, and azo dyes. The halogenated emulsion layer and V/or the hydrophilic colloid layer of the photosensitive material reduce the gloss of the photosensitive material and improve the addability.
A matting agent can be added to prevent photosensitive materials from sticking together. A lubricant can be added to the photosensitive material to reduce sliding friction. An antistatic agent may be added to the photosensitive material for the purpose of preventing static electricity.An antistatic agent may be used in the antistatic layer on the side of the support on which the emulsion is not laminated, and may be added to the emulsion layer and/or the support. On the other hand, antistatic agents preferably used in protective colloid layers other than the emulsion layer on the side on which the emulsion layer is laminated are the compounds described in RD 17643 x■. The photographic emulsion layer and/or other hydrophilic colloid layer of the light-sensitive material may be coated with coating properties, antistatic properties, slipperiness properties, emulsification dispersion,
Various surfactants can be used for the purpose of preventing adhesion and improving photographic properties (promotion of development, high contrast, sensitization, etc.). The support used in the photosensitive material of the present invention includes α-olefin polymers (e.g., polyethylene, polypropylene,
Flexible reflective supports such as paper laminated with ethylene/butene copolymer), synthetic paper, etc., semi-synthetic or synthetic polymers such as cellulose acetate, cellulose nitrate, polystyrene, polyvinyl chloride, polyethylene terephthalate, polycarbonate, polyamide, etc. These include films made of , flexible supports made of these films with reflective layers, glass, metals, ceramics, etc. The hydrophilic colloid layer of the photosensitive material is coated on the surface of the support by corona discharge, ultraviolet irradiation, flame treatment PI!, etc. as necessary. Improving adhesion, antistatic properties, dimensional stability, abrasion resistance, hardness, anti-yielding properties, friction properties, and/or other properties directly or on the surface of the support. It may be coated through one or more subbing layers. When coating photosensitive materials, thickeners may be used to improve coating properties.For example, thickeners, such as hardeners, have quick reactivity and can be added to the coating solution in advance to prevent deltation before coating. For substances that may cause turbulence, it is preferable to mix them using a static mixer or the like immediately before spraying. As a coating method, extrinsic coating and curtain coating, which can simultaneously coat 21!1 or more layers, are particularly useful, but packet coating may also be used depending on the purpose. Further, the coating speed can be arbitrarily selected. The light-sensitive material of the present invention can be exposed to electromagnetic waves in the 1i range of the spectrum to which the emulsion layer constituting the light-sensitive material of the present invention is sensitive. Light sources include natural light (sunlight), tungsten electric lamps, fluorescent lamps, mercury lamps, xenon arc lamps, carbon 7-ta lamps, senon flash lamps, cathode mW flying spots, various laser beams, luminescent light, electron beams, X# Any known light source can be used, such as light emitted from a phosphor excited by a, gamma ray, a#i, etc. The fog light time is not only an exposure time of 1 millisecond to 1 second, which is normally used with a camera, but also an exposure shorter than 1 microsecond, such as an exposure time of 100 nanoseconds to 1 microsecond using a cathode ray tube or xenon flash lamp. It is also light and allows exposures longer than 1 second. Even if the exposure is carried out continuously,
It may be performed intermittently. A known method can be used to develop the photosensitive material of the present invention. The processing temperature used is between 18°C and 50°C, and depending on the purpose, any of black and white photographic processing, lithographic development processing, or color photographic processing to form a dye image can be applied. Black-and-white photographic processing uses dihydroxybenzenes (e.g., hydroquinone), 3-pyrazolidones (e.g., 1-phenyl-3-pyrazolidone), and 7-minofenol M (e.g., N-methyl-1]-7-minofenol) as developing agents. ), ascorbic acid, etc. can be used alone or in combination. The developer also contains other known preservatives, alkaline agents, and 1) F.
Contains class I chemical agents, capri inhibitors, etc., and further contains solubilizers, color toning agents, development accelerators, surfactants, antifoaming agents, etc.
It may also contain water softeners, hardeners, etc. The present invention can also be applied to so-called herbal medicine built-in type photosensitive materials in which a developing agent is contained in the photosensitive material and processed in an alkaline bath. Next, when forming a dye image, an alkaline aqueous solution containing a color developing agent is used. The color developing agent may be a known primary aromatic amine developer such as phenylene diamine. Color developers also contain alkali metal sulfites, carbonates, borates, and phosphates such as p r-r 4
1 sanitizing agents, haf'n salts, and organic antifoggants, water softeners, preservatives, organic solvents such as benol alcohol and ethylene glycol, and development accelerators such as quaternary ammonium salts and amines. You can stay there. Processing after color development is usually a bleaching process. The bleaching solution may be applied simultaneously with the fixing process or separately. Examples of the bleaching agent include compounds of polyvalent metals such as iron (U), cobalt (I [I), chromium (■), copper (II)], Persulfates and the like are used. For example, 7-erocyanide, heavy amate salts, Fp1 complex salts of iron and cobalt, ethylene-7-amine acetic acid, nitrilotriacetic acid, persulfates, permannates, and the like can be included. [Examples] The present invention will be explained in more detail by giving examples below. Example-1 As a comparative emulsion, a high-sensitivity silver iodobromide emulsion (octahedral grains) containing 3.0 mol% of silver iodide was chemically ripened to the highest Oi sensitivity using the gold-over-sulfur sensitization method. After that, 4-hydroxy-6-methyl-1,3,3 per mole of silver halide
Ripening was stopped by adding 1.02 of a,7-tetrazaindene. This emulsion is designated as Em8-3. Separately, as an emulsion of the present invention, high-sensitivity 7ym silver iodide milk/F'J (dodecahedral grains) containing 3.0 mol % of silver iodide was subjected to similar chemical ripening and ripening termination. This emulsion is designated as Em12-3. The obtained emulsions (E-12) and (Em8 3) were
Divide each and use one part as a blank sample.
In addition, the compounds according to the present invention as shown in Table 1 below were added and, after sufficient adsorption, an appropriate amount of saponin as a coating aid and an appropriate amount of formalin as a hardening agent were added to prepare an emulsion. The obtained emulsion was injected onto a subbed polyester base.
The samples were uniformly coated so as to have a value of 3117z2 and then dried to prepare samples No. 16!1 (No. 1 to 16). The photographic materials prepared as described above were used as 7 lettuce samples, one that was left at room temperature for three days, one that was kept at a temperature of 65°C and a relative humidity of 7% for three days, and one that was kept at a temperature of 50°C and a relative humidity of 80% for three days. A forced aging sample was prepared after being left unattended. After this, exposure was performed using a regular sensitometry wedge, and then the following J! ! ! After developing and fixing with solution [AI at 35° C. for 30 seconds, the film was washed with water and dried, and the sensitivity was measured. Process 11 [[AI (Developer for black and white photographic materials) 1-phenyl-3-pyrazolidone 1.511 Hydroxy 7
3025-2) Cyinzole 0.25y Potassium bromide 52 Anhydrous sodium sulfite 55° Potassium hydroxide 30° Boric acid
Add 10g gulguraldehyde (25%) and 5g water to bring the total amount to 11. The results obtained are shown in Table 1 below. However, the fog value indicates the value after subtracting the base density, and the sensitivity value is calculated from the sensitivity at the fog value + 0.5 position, with the blank sample (No. 1) of the emulsion of the present invention left for 3 days as 100. This is the relative sensitivity expressed. As is clear from Section 1a above, the sample according to the present invention has the following margins:
It can be seen that in all cases, the occurrence of fog was suppressed despite the harsh storage conditions, and the stability of the film during storage was improved. Example 2 A high-sensitivity silver iodobromide emulsion as shown below was chemically ripened using a gold-plated sulfur sensitizer to the highest sensitivity. Emulsion Grain crystal type Silver iodide content Next, an appropriate amount of 5°5'-diphenyl-9-ethyl-3,3'-no-γ-sulfopropyloxacarbocyanine sodium salt was added to each emulsion as a green-sensitizing dye. ,
A green-sensitive silver halide emulsion was prepared. Then, per mole of silver halide, as magenta coupler, 1-(2,4,6-)lichloro7el)-3-
80 g of [3-(2,4-not-7mil7e/xyacetamido)benzamide]-5-pifuzolone as a colored magenta coupler, 1-(2,4,6-)licrophenyl)-4-( 1-su7tylazo)-3-(2-
Chlo-a-5-octadecenyl succinimide anilino)
Weighed 2.5 g of -5-pyrazolone, then trifrenor phosphate (120 g), 240 m of ethyl acetate.
g was mixed and dissolved by heating, then siliisopropylna 7
A coupler solution emulsified and dispersed in a solution of 5 g of sodium talenesulfonate and 550 ii' of a 7.5% aqueous gelatin solution was added to the above emulsion. Divide each emulsion and use one part as a blank sample. Comparative compounds and compounds according to the present invention as shown in Table 2 below are added to the emulsion and sufficiently adsorbed, followed by a gelatin hardener. A suitable amount of 2-hydroxy-4,6-nochlorotrianone sodium was uniformly added thereto to prepare a silver halide emulsion. This emulsion is mixed with 3. A sample was obtained by uniformly coating and drying on a triacetate film that had been subbed so as to achieve Oy/z2 (No, 17-44). The obtained film sample was subjected to the same forced deterioration test as in Example 1, then wedge exposed in the usual manner and color developed according to the following color processing steps. The color sensitometry results obtained from the obtained pieces are shown in Table 2 below. The fog in the table is the value obtained by subtracting the base concentration, and the sensitivity is the relative sensitivity when the E+e12-3 blank sample left for 3 days (sample No. 17) is expressed as 100. Processing process [Processing temperature 38℃] Processing time Color development
Bleach for 3 minutes and 15 seconds
Wash with water for 6 minutes and 30 seconds
3 minutes 15 minutes arrive at Sunamuro
Wash with water for 6 minutes and 30 seconds
Stabilization for 3 minutes 15 seconds Drying for 1 minute 30 seconds Places used in each treatment process J! I! 'o, the composition is as follows. [Color developer] 4-7 minnow 3-methyl-N-ethyl-N-(β-hydroxyethyl)aniline sulfate 4.75g
Anhydrous sodium sulfite 4. zsy Hydroxylamine 1/2 sulfate 2.0g Anhydrous potassium carbonate 37.5g Sodium bromide 1.33 Nitrilotriacetic acid 3
Sodium salt (monohydrate) 2.5g Potassium hydroxide 1.0g Add water to make 11, and use sodium hydroxide to make p) 110.
Adjust to 6. [Bleach] Ethyleneoaminetetraacetic acid iron ammonium salt ioo, o,
. Ethylenediaminetetraacetic acid diammonium salt 10, Of ammonium bromide iso, og glacial acetic acid 10.0# Add water to make 11, use aqueous ammonia, ) (6, OL:
adjust. [Fixer] Ammonium thousand sulfate 175.0g Anhydrous sodium sulfite 8.6g Sodium metasulfite 2.3g Add water to make 11, and use acetic acid to adjust to p+ (6,0. [Stabilizing solution] Formalin (37 % aqueous solution) 1.5ml
Konigux (Konishiroku Photo Industry Co., Ltd.! 7.5z1 Add water to make 11. Comparative compound (a) #42 From the results in table, the general formula used in the present invention (
It can be seen that the compound 1) provides antifogging properties with no decrease in sensitivity in forced deterioration tests under high temperature or high humidity compared to conventionally known compounds. Example 3 A multilayer color photosensitive material sample was prepared by sequentially providing each layer having the composition shown below on a cellulose triacetate film support. However, the third layer, fourth layer, sixth layer, seventh layer, I
The present invention emulsion (Em12) and comparative emulsion (Em8) shown below were used in the silver halide emulsion layers of the jSS layer and the upper VtjS10 layer, respectively. 1st layer: Antihalation layer Black gelatin layer containing colloidal silver 2nd layer: Intermediate gelatin layer 3rd layer: Red-sensitive low-sensitivity emulsion layer Silver iodobromide emulsion Troweled side [・4.79g 7m” Sensitizing dye■ ...6 x 10-' per mole of silver
Molar sensitizing dye■...3X10-' per mole of silver
Molar coupler A: 0.06 mol per mol of silver. Coupler C: 0.003 mol per mol of silver. Coupler D: 0.06 mol per mol of silver. 003
03 Molt triphrenor phosphate amount 0.3 cc/z” 4th layer: Red-sensitive high-sensitivity emulsion layer Silver iodobromide emulsion Silver coating amount...L4 g/z2
Sensitizing dye■...3X10-' per mole of silver
Molar sensitizing dye ■・・・1.2X 1 per mole of silver
0-' mole coupler F...0.0125 per mole of silver
Molar coupler C...0.0016 per mole of silver
Malt reflex phosphate coating amount 0.2cc/z” 5th layer: Intermediate layer Same as 2nd layer 6th layer: Green sensitive low sensitivity emulsion layer Silver iodobromide emulsion Silver coating amount... Bow-Og/ z"
Sensitizing dye■・・・3×10 per mole of silver
-'molar sensitizing dye■...1Xl0-' per mole of silver
Molar coupler B: 0.08 mole per mole of silver Coupler M: o, oos per mole of silver Molar coupler D: 0.08 mole per mole of silver 0015
Malt reflector phosphate coating amount 1.4cc/II'' 7th layer: Green sensitivity Sensitive emulsion layer Silver iodobromide emulsion Silver coating amount...1.6g/x
2 Concentrating dye ■・・・2.5X per mole of silver
10-'mol sensitizing dye ■...0.8x 1 per mole of silver
0-' mole coupler B...0.02 moles per mole of silver Coupler M...0.003 moles per mole of silver Triphrenorphosphate Coating amount 0.8cc/2nd 8th layer: Yellow filter single layer gelatin layer containing yellow colloidal silver in an aqueous gelatin solution. 9th layer: Blue-sensitive low-sensitivity emulsion layer Silver iodobromide emulsion Trowel coating 1631--0.5g/z
2 Coupler Y...0.1 per 11 moles of ff
25 mol triphrenor phosphate coating amount 0.3cc/2 10th layer: Blue sensitive high sensitivity emulsion layer Silver iodobromide emulsion Trowel coated side 1--0.6g/t" coupler Y...Silver 1 Coating amount: 0.04 mol triphrenol phosphate 0.1 cc/foot 2 11th layer: Protective layer A gelatin layer containing polymethyl methacrylate particles (diameter 1.5 μl) is applied.The coupler in each layer is triphrenol phosphate and Add the coupler to a solution of ethyl acetate, add sodium p-dodenlebenzenesulfonate as an emulsifier, and dissolve by heating.
The mixture was mixed with a heated 10% gelatin solution and emulsified using a comid mill. In addition to the above composition, a gelatin hardener and a surfactant were added to each layer. The sample prepared as above was used as a blank sample (No. 4).
5 and 52). Compound sensitizing dye I used to prepare the sample: 7-hydro-s, s'-dichloro-3゜3
'-di(γ-sulfopropyl)-9-ditiruthiacarposi7ine hydroxide bilinium salt sensitizing dye■:
Anhydro 9-ethyl-3,3'-(γ-sulfopropyl)-4,5,4',5'-nopenzothiacarpocyanine hydroxide triethylamine salt sensitizing dye m: Anhydro 9-ethyl-5, 5'-dichloro-3,3'-di(γ-sulfopropyl)oxacarposi7ine hydroxide sodium salt sensitizing dye■:
7Nhydro5.6.5',6'-tetrachloro1.1'-noethyl-3,3'-di(β-[β-(γ-
sulfopropoxy)ethoxy]ethylimigzolocarbocyanine hydroquine sodium salt-1+\ coupler\ Coupler B Coupler C H Coupler D Coupler F I Coupler Y The emulsion layers of the above-mentioned blank samples for the present invention and for comparison are as follows: In both cases, after adding the above-mentioned sensitizing dye, 1 g of 4-hydroxy-6-methyl-1,3,3a7-tetrazaindene, known as a ripening stopper, was added per mole of silver halide.
This was used as a blank emulsion. Next, the anti-capri agents of the present invention and the comparative anti-capri agents were added as shown in Table 3, and after they were sufficiently adsorbed, couplers, trifrenor phosphate, etc. were added as described above, and then 2 was added as a hardening agent. -Adjusted by adding an appropriate amount of hydroxy-4,6-nochlorotri7nonsodium, 12 types of samples were coated in a multilayer manner (No. 46-51 and 53-58).
). The obtained multilayer color photosensitive material was left for two days at a temperature of 65°C and 7% relative temperature as a forced deterioration test, and then subjected to normal wedge exposure and then subjected to the same color processing as in Example 2. . The obtained color sensitometric results are shown in Table 3 below. Note that Capri in the table indicates the value after subtracting the base concentration, and the sensitivity value is for the Kagetsu 11E m12 blank sample (No. 4).
The relative sensitivity is expressed as 100, which is the sensitivity of each of the red-sensitive layer, green-sensitive layer, and blue-sensitive layer of 5) after 2 days of natural storage. Comparative Compound (b) From the results in Table 3 below, it can be seen that the samples according to the present invention show no deterioration of photographic properties in each layer and low desensitization, even in multilayer color light-sensitive materials, despite severe storage conditions. It is clear that a suppressive effect can be obtained.

Claims (1)

[Scope of Claims] At least one silver halide emulsion layer containing dodecahedral crystal silver halide grains whose surface is a (110) plane, and at least one compound represented by the following general formula [I]. A silver halide photographic material comprising: General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, Z is -SO_3M^2, -COOR^1, -O
Represents a heterocycle having directly or indirectly at least one group selected from H and -NHR^2, M^1 and M
^2 is each a hydrogen atom, an alkali metal or -NH_4
represents a group, R^1 represents a hydrogen atom, an alkali metal, or an alkyl group having 1 to 6 carbon atoms, and R^2 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, -COR^3, -COOR^3
or -SO_2R^3, where R^3 represents a hydrogen atom, an aliphatic group or an aromatic group. ]