JPH04204725A - Photographic spectrally sensitized dyestuff - Google Patents

Abstract

PURPOSE:To obtain a silver halide photographic sensitive material having sensitizability by 5.1-12.9 times and small in fog and and high in sensitivity by using a specified dyestuff. CONSTITUTION:The dye to be used is represented by formula I in which A is an atomic group necessary to form a thiophene ring; Z is an atomic group necessary to form a 5-or 6-membered N-containing hetero ring; and R is alkyl, aralkyl, or alkenyl. This sensitizing dyestuff has a molecular structure characterized by having as one of 2 rings, a 5-oxazolinone ring substituted by thienylmethylene group on the 4-position, thus permitting the obtained silver halide photographic sensitive material has sensitizability by 5.1-12.9, small fog, and high sensitivity.

Description

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

The present invention relates to photographic spectral sensitizing dyes, and more particularly to dyes useful as sensitizing dyes used in silver halide photographic light-sensitive materials.

[Conventional technology]

Silver halide photographic materials are required to have high sensitivity in different specific wavelength ranges depending on their intended use. As one of the manufacturing techniques for such silver halide photographic light-sensitive materials, various types of cyanine dyes and merocyanine dyes are added to silver halide photographic emulsions. It is generally well known that the sensitivity in a specific wavelength range can be extremely effectively increased. When applying spectral sensitization to silver halide photographic emulsions using dyes, it is necessary not only to simply impart a spectral sensitizing effect and increase sensitivity, but also to satisfy the following requirements. (1) The spectral sensitization region is appropriate. (2) The photosensitive material must maintain stable photographic properties during storage. (3) No staining or fogging due to residual dye administered for spectral sensitization should be avoided after development. (4) No negative interactions with other photographic additives, such as ζ4 (
required. However, although a large number of cyanine and merocyanine dyes have been known to date, they have poor photographic properties such as sensitization.
The reality is that there are few that satisfy the above factors.

[Purpose of the invention] Therefore, an object of the present invention is to provide an excellent photographic spectral sensitizing dye that satisfies the above requirements. [Structure of the invention]

As a result of various studies, the present inventors have discovered that the dye represented by the following general formula (I) is an excellent dye that satisfies the above objectives. General Formula (I) In the above general formula (1), A represents an atomic group necessary to form a thiophene ring, and the thiophene ring includes a narkyl group (for example, methyl, ethyl, etc.), a halogen atom (
For example, chlorine, bromine, etc.) may be substituted. Z represents an atomic group necessary to form a 5- or 6-membered nitrogen-containing heterocycle. Specific examples thereof include, for example, an oxazoline ring, an oxazole ring, a benzoxazole ring, a benzisoxazole ring, a naphthoxazole ring, a thiazoline ring, a thiazole ring, a benzothiazole ring, a naphthothiazole ring, a selenazoline ring, a selenazole ring, a benzoselenazole ring, naphthoselenazole ring, tellurazole ring,
These include penzotelllazole ring, naphtotellazole ring, pyridine ring, quinoline ring, benzoquinoline ring, indolenine ring, benzindolenine ring, benzimidazole ring, naphthoimidazole ring, pyrroline ring, etc., and these heterocycles and fused rings include In addition to the alkyl groups and halogen atoms mentioned in A above, the benzene ring and naphthalene ring include alkoxy groups (e.g. methoxy, ethoxy, etc.), hydroxy groups, carboxy groups, alkoxycarbonyl groups (e.g. methoxycarbonyl, ethoxycarbonyl). etc.), an aryl group (for example, phenyl), and the like. R is an alkyl group (e.g. methyl, ethyl, propyl,
Lower alkyl groups such as butyl, β-hydroxyethyl, γ
-Hydroxyalkyl group such as hydroxypropyl, β-
Alkoxyalkyl groups such as methoxyethyl and γ-methoxypropyl; acyloxyalkyl groups such as β-acetoxyethyl, γ-acetoxypropyl and β-benzoyloxyethyl; carboxyalkyl groups such as carboxymethyl and β-carboxyethyl; methoxycarbonylmethyl , ethoxycarbonylmethyl, alkoxycarbonylalkyl groups such as β-ethoxycarbonylethyl, sulfoalkyl groups such as β-sulfoethyl, γ-sulfopropyl, δ-sulfobutyl, etc.), aralkyl groups (e.g., benzyl, phenethyl, sulfobenzyl, etc.) , alkenyl group (
For example, allele). As is clear from the above, the sensitizing dye of the present invention is a novel cyanine-based cyanine-based molecular structure characterized by having a 5-oxysilidinone ring with a thienylmethyl group bonded to the 4-position in one nucleus. . Next, among the sensitizing dyes represented by the general formula (I) of the present invention, typical examples and their maximum absorption values of methanol solutions (
nm). (Left below) Sensitizing dye (1) Sensitizing dye (5) Sensitizing dye (6) Sensitizing dye (7) Sensitizing dye (8) ■ (CI(!) s SO,Na Sensitizing dye (9) Sensitizing dye (10) Sensitizing dye (11) Sensitizing dye (13) Sensitizing dye (14) Sensitizing dye (15) Sensitizing dye (16) Sensitizing dye (17) Sensitizing dye (18) Sensitizing Dye (19) C, H. Sensitizing dye (21) Sensitizing dye (22) Sensitizing dye (23) Sensitizing dye (24) 603.561 Next, the dye represented by the general formula (1) of the present invention Among them, a typical synthesis example will be described.Synthesis of sensitizing dye (4): 2-Methyl-4-(2-thienylmethylene)-5-oxazolidinone (synthesis 5YNTHESI3198)
3(11), p. 899) and 4.79 g of acetanilide vinyl-3-methyl-6-dimethylaminobenzothiazolium iodide were mixed, and 30 ml of acetonitrile was further added thereto, followed by heating and refluxing. 3.03 g of hetriethylamine was added thereto, and heating and refluxing was continued for 10 minutes. After cooling to a greenhouse, the precipitate was collected by filtration and washed with acetonitrile. After drying, a black-purple powder with a melting point of 257.0°C (decomposed) 2.2
Obtained 0g. Maximum absorption value of methanol solution is 585 nm
Met. H-N, M, R, (CDCIs/TMS 1
nl) ppl: 296 (s, 6H) 3.40
(s, 3H)5.62-((1,IH)5.sl (d
, IH) 6°70 (m, IH) 6.80-6.88
(m, 2H) 7.07-7.13 (m, 2H) 7.4
5-7゜60 (m, 3H) IR (KBr) C-o 1. 770 cm-' Synthesis of sensitizing dye (17) 2.07 g of 2-methyl-4-(5-methyl-2-thienyl)methyleneoxazolidin-5-one and 2-anilinovinyl-5-chloro-3-ethyl- 6-Methylbenzoxazolium-p-toluene□ Sulfonate 4.57
10.0 ml of acetic anhydride and 3.03 g of triethylamine were added thereto, and the mixture was heated and stirred at 90 to 95°C for 15 minutes. After cooling, the precipitated crystals were collected by filtration and washed with acetonitrile. After drying, black-blue crystalline powder 1 with a melting point of 249.0°C (decomposed)
．． Obtained 50g. Maximum absorption value of methanol solution is 525
It was nm. Other sensitizing dyes represented by the general formulas of the present invention can also be easily synthesized according to the above synthesis examples. The silver halide photographic emulsion in which the sensitizing dye of the present invention represented by the above general formula is used is silver chloride, silver bromide, silver chlorobromide, silver iodobromide, silver chloroiobromide produced by a conventional method. Any material such as silver may be used. In order to add the sensitizing dye of the present invention to these silver halide photographic emulsions, an organic solvent such as methanol, ethanol, acetone, cellosolve, pyridine, dimethylformamide, etc., which is optionally miscible with an aqueous solution or water, may be used alone or in combination. It can be added as a solution. These sensitizing dyes may be added to the silver halide photographic emulsion at any time during the emulsion manufacturing process, but it is generally preferable to add them immediately after the second ripening. The amount added varies depending on the type of sensitizing dye or the type of silver halide photographic emulsion, but it can be used in a wide range of about 5 to 2,000 mg per 100 g of silver nitrate. The silver halide photographic emulsion in which the sensitizing dye of the present invention is used has been subjected to noble metal sensitization, sulfur sensitization, reduction sensitization, sensitization in combination thereof, or addition of polyalkylene oxide compounds, etc. Good too. The silver halide photographic emulsion in which the sensitizing dye of the present invention is used may be spectrally sensitized by using other sensitizing dyes, such as known cyanine and merocyanine dyes, if necessary, and further by a known method. Additions like stabilizers, surfactants, hardeners, optical brighteners, UV absorbers, filter dyes, anti-irradiation dyes, anti-halation dyes, preservatives, plasticizers, matting agents, color couplers etc. can contain agents. Furthermore, when used in a photosensitive material for stabilization processing, a developing agent or its precursor can be included. Protective colloids for silver halide photographic emulsions in which the sensitizing dye of the present invention is used include, in addition to gelatin, gelatin derivatives such as phthalated gelatin and romanticized gelatin, cellulose derivatives, soluble starch, and water-soluble polymers. . Examples of the support on which the silver halide photographic emulsion using the sensitizing dye of the present invention is coated include baryta paper, plastic laminated paper, synthetic paper, and resin films such as cellulose triacetate and polyethylene terephthalate. can. These supports can also be provided with a subbing layer and an antihalation layer by a known method, if necessary.

【Example】

The present invention will be described in detail below based on Examples, but the present invention is of course not limited thereto. Example 1 A 0.05% methanol solution of the sensitizing dye of the present invention was added to a silver bromide emulsion prepared by the double jet method at a concentration of 1.0 g per gram of silver nitrate. 2+nl was added. This emulsion was incubated in a bath at 40° C. for 45 minutes to stabilize the spectral sensitization. Thereafter, predetermined amounts of a stabilizer, a surfactant, and a hardening agent were added, and then coated on a paper support laminated with polyethylene, dried, and left at 35° C. overnight. Next, cut it to an appropriate size to obtain a test sample, and IOS
It was exposed according to the law. Each sample was then treated with D-72 developer (
20 using American Eastman Kodak developer formulation)
The development was carried out for 90 seconds at .degree. C., stopped, fixed, washed with water, and after drying, a strip with a predetermined black and white image was obtained. This is MACHBE manufactured by Macbeth Corporation in the United States.
Density was measured using a THTD150 densitometer to obtain sensitivity and fog. The optical density reference point for determining the sensitivity was a point of 0.75. Furthermore, the sensitivity was expressed as a relative value, with the sensitivity of an unadded sample to which no sensitizing dye was administered as 1.0. The results obtained are shown in Table 1. (The following is a blank space) Table 1 As is clear from Table 1, the sensitizing dye of the present invention is characterized by excellent sensitization and low fog. Therefore, by using the sensitizing dye of the present invention, a silver halide photographic material with high sensitivity can be obtained. Furthermore, no coloration (color stain) due to residual dye was observed after the development process. Example 2 A sample was prepared and tested in the same manner as in Example 1 except that the silver halide was silver chloride. The results obtained are shown in Table 2. (The following is a blank space) Table 2 As is clear from Table 2, the sensitizing dyes of the present invention range from 5.1 to
It is characterized by having 12.9 times higher sensitivity and less fog. Therefore, by using the sensitizing dye of the present invention, a silver halide photographic material with high sensitivity can be obtained. Further, no coloration (color stain) due to residual dye was observed.

Claims (1)

[Claims] 1. A photographic spectral sensitizing dye represented by the following general formula (I). General formula (I) ▲ Numerical formulas, chemical formulas, tables, etc. Represents a necessary atomic group.R represents an alkyl group, an aralkyl group, or an alkenyl group.)