US3793034A

US3793034A - Spectrally sensitized silver halide photographic emulsions

Info

Publication number: US3793034A
Application number: US00227026A
Authority: US
Inventors: A Sato; K Shiba; H Takei
Original assignee: Fuji Photo Film Co Ltd
Current assignee: Fujifilm Holdings Corp
Priority date: 1971-02-18
Filing date: 1972-02-17
Publication date: 1974-02-19
Anticipated expiration: 1991-02-19
Also published as: GB1376020A; JPS5434328B1; DE2207496A1

Abstract

A silver halide photographic emulsion having high spectral sensitivity in the range 510-533 m Mu containing at least one sensitizing dye represented by the following formula (1):

WHEREIN Z1 and Z2 each represent a group of nonmetallic atoms necessary to complete a benzene ring, the hydrogen atoms of which may be substituted by substituents.

Description

Sato et al.

[4 1 Feb. 19, 1974 SPECTRALLY SENSITIZED SILVER HALIDE PHOTOGRAPHIC EMULSIONS [75] Inventors: Akira Sato; Keisuke Shiba; Haruo Takei, all of Kanagawa, Japan [73] Assignee: Fuji Photo Film Co., Ltd.,

Kanagawa, Japan [22] Filed: Feb. 17, 1972 [21] Appl. N0.:.227,026

[30] Foreign Application Priority Data Feb. 18, 1971 Japan 46-7525 [52] US. Cl. 96/137, 260/240.6 [51] Int. Cl G03c 1/18 [58] Field of Search 96/ 1-37 [56] References Cited UNITED STATES PATENTS 2,918,369 12/1959 Doorenbos 96/132 3,244,526 4/1966 Copeland 96/132 3,656,957 4/1972 Oliver et al. 96/127 Primary Examiner-J. Travis Brown Attorney, Agent, or Firm-Sughrue, Rothwell, Mion, Zinn & Macpeak ABSTRACT A silver halide photographic emulsion having high spectral sensitivity in the range 510-533 mp. containing at least one sensitizing dye represented by the following formula (1):

wherein Z and Z each represent a group of nonmetallic atoms necessary to complete a benzene ring, the hydrogen atoms of which may be substituted by substituents.

8 Claims, 1 Drawing Figure SPECTRALLY SENSITIZED SILVER HALIDE PHOTOGRAPHIC EMULSIONS The present invention relates to silver halide photographic emulsions containing new sensitizing dyes, and particularly to silver halide photographic emulsions having a high spectral sensitivity at a range of 5 l0 533 mu.

it has been well-known that the sensitive wave length range of silver halide emulsions is extended by addition of sensitizing dyes thereto and the silver halide emulsions are spectrally sensitized.

The spectral sensitization often is affected by the chemical structure of the sensitizing dyes. Namely, since the formation of a J-aggregate of the sensitizing dyes is influenced by the chemical structure, for example, kinds of heterocyclic nuclei and kinds of substituents, a sensitization of near the spectral sensitization maximum caused by the J-aggregate of the sensitizing dyes adsorbed on the surface of silver halide particles is influenced extremely by the chemical structure of the sensitizing dyes used. Accordingly, selection of the sensitizing dye used is very important in the case of highly sensitizing the desired specified wave length range of the photographic sensitive material.

The present inventors have found that the following new sensitizing dyes form the J-aggregate and are useful for high spectral sensitization of a range of 510 533 mp.

An object of the present invention is to provide silver halide photographic emulsions having a high spectral sensitivity at about 510 533 my. which do not leave stain after development.

The object of the invention has been attained by adding novel sensitizing dyes represented by the following formula (1) to silver halide photographic emulsions.

l H N N I :z. =CH--CH=ti7- z '2 X lq N I R2 which are electron attractive substituents known in the common benzimidazolocarbocyanines include halogen atoms (e.g. fluorine atom, chlorine atom and bromide atom), trifluoromethyl group, alkylsulfonyl groups (e.g., a methylsulfonyl group etc.), sulfamyl group, alkylaminosulfonyl groups (e-g-;, methylaminosulfonyl group and ethylaminosulfonyl group), dialkylaininosulfonyl groups (e.g., dimethylaminosulfonyl group, diethylaminosulfonyl group, piperidinosulfonyl group, morpholinosulfonyl group and .pyrrolidinosulfonyl group etc.), cyano group, carboxyl group, alkoxycarbony] groups (e.g., methoxy-carbonyl group and ethox-* ycarbonyl group etc.) and acyl groups (e.g., acetyl group and benzoyl group etc.). A preferred substituent is the chlorine atom. The substituents of Z, include alkyl groups (e.g., methyl group etc.), halogen atoms (e.g., fluorine atom, chlorine'atom and bromine atom etc.) and alkoxy groups (e.g., methoxy group etc.). R, and R which are identical or different each represent an alkyl group preferably having up to 8 carbon atoms [i.e., unsubstituted alkyl group and substituted alkyl 2 group; (e.g., methyl group, ethyl group, n-propyl group, n-butyl group and cyclohexyl group etc. a hydroxyalkyl group (e.g., B-hydroxyethyl group, 'y-hydroxypropyl group), an acetoxyalkyl group (e.g., B-acetoxyethyl group; 'y-acetoxypropyl group), an alkyl group containing a carboxy radical (e.g., carboxymethyl group, B-carboxyethyl, group, 'y-carboxypropyL group, 8-carboxybutyl group, p-carboxybenzyl group and p-carboxyphenethyl group), a cyanoalkyl group (e.g., B-cyanoethyl group, 'y-cyanopropyl group, S-cyanobutyl group), a carbamoylalkyl group (e.g., B-carbamoylethyl group, y-carbamoylpropyl group, o-carbamoylbutyl group, B-N-ethylcarbamoylethyl group, y-N-ethylcarbamoylpropyl group, 6-N methylcarbamoylbutyl group), a sulfamoylalkyl group (e.g. 'y-sulfamoyl propyl group, 'd-sulfamoyl butyl group), an aminosulfonyl alkyl group (e.g., 'y-N- ethylaminosulfonyl propyl group, 8-N- ethylaminosulfonyl butyl group), an alkyl group containing a sulfo radical (e.g., B-sulfoethyl group, y-sulfopropyl group, 'y-sulfobutyl group, S-sulfobutyl group, p-sulfobenzyl group and p-sulfophenethyl group), an aralkyl group (e.g., benzyl group, phenethyl group) and an ally] group (e.g., vinylmethyl group) etc.]. A preferred substituent is the substituted alkyl group containing a sulfo or carboxy radical. In the case that one of R and R, has a sulfo radical or carboxyl radical as the substituent, for example, in the case of 'y-sulfopropyl group, it is supposed that an inner salt having the following formula (II) is formed.

611, omen. s 0:

The characteristic of the chemical structure of the sensitizing dyes used in the present invention is that Z, has a benzimidazole nucleus as defined in formula (1).

a range of about 510 533 mu, since the spectral sensitization range becomes broad in the long wave length side.

In the following, typical examples of the new sensitizing dyes represented by the formula (1) used in the .present invention are shown. However, they are not intended to be limitative thereof.

Dyel CzHi I H N N g w CHCH=C N N The sentitizing dyes represented by the formula (1) can be prepared by reacting a compound represented by the following formula (III) NR m e mwmmmefi E -CH=CHN N 7 loan. L, I m) wherein 2,, R, and R each represent the same meaning as in formula l X represents an anion (e.g., bromine ion and iodine ion etc.), and n represents 0 or 1 (n=0 when the inner salt), with a compound represented by the following formula (IV) in an alcohol in the presence of triethylamine by heating under reflux. Example of synthesis.

utes in ml of ethanol in the presence of 3ml of triethylamine by refluxing on a hot water bath. Crystals precipitated on the way of the reaction. After cooling, the

mixture was filtered. By washing with hot ethanol, 0.7g of Dye 5 having above 300C- of a boiling point was obtained.

Other dyes could be prepared by the same procedure as abovementioned.

Silver halide photographic emulsions can be spectrally sensitized by the sensitizing dyes used in the present invention. Especially, they are effective for increasing a'sensitive range of the gelatin-silver halide photographic emulsions. Further, photographic emulsions containing a hydrophilic colloid besides gelatin such as agar. agar, collodion, cellulosederivatives, polyvinyl alcohol and synthetic or natural hydrophilic resins can be sensitized by the above-mentioned dyes.

In the emulsions used in the present invention, many kinds of silver salts such as silver bromide, silver iodobromide, silver bromochloride and silver iodobromochloride can be used.

In order to prepare the sensitized photographic emulsions of the present invention, the sensitizing dyes may be added to the photographic emulsions by any common method. In general, the sensitizing dyes are added to the emulsions as a solution prepared by dissolving in a suitable solvent such as methanol, methyl cellosolve and pyridine etc. The amount "of the sensitizing dyes added to the emulsions can vary in a range of 5-200 mg of dye per kg of the emulsions according to the desirable efiect. However, this amountis not limitative.

Known sensitizing dyes may be added additionally to the photographic emulsions of the .present invention.

At production of the photographic emulsions of the present invention, sensitizing agents, stabilizers, toning agents, hardening agents, surface active agents, antifogging agents, plasticisers, development accelerators, color formers, fluorescent whitening agents and ultraviolet ray absorbing agents can be added to the emulsion by any common method.

The photographic emulsions of the present invention can be applied to suitable supports, for example, glass films of cellulose derivatives, films of synthetic resins, baryta paper, resin coated paper and synthetic paper by any common method.

In the following, examples are shown.

Silver halide photographic emulsions were prepared by adding sensitizing dyes above-mentioned to a gelatin silver iodobromide emulsion (molar ratio: Br I 93 v 7). The emulsions were applied to cellulose triacetate films. After drying, the films were exposed to light through a yellow filter made by Fuji Photo Film Co. (filter through which rays having a wave length of longer than 480 my. pass) using a day-light lamp of 64 5 luxes (corresponding to 5,400K) and developed. The developer having the composition represented in Table l was used. 7

TABLE 1 Metal 2 g Sodium sulfite 1 g Hydroquinone 5 g Borax' 2 8 Water to make 1 liter In Table 2, spectral sensitization and wave length of the sensitization maximum obtained by adding the sensitizing dyes of the present invention and sensitizing dyes for comparison to the silver iodobromide emulsion are shown.

TABLE 2 Ex. Dye No. Amount of Wave length R9) tive No. dye (2 l0" o spectr molar sensitization sensitivity concentration maximum mg.

ml/ 100 g of H emulsion) 1 1 s 515 I00 2 2 8 520 225 3 3 8 5l2 140 4 4 8 520 lZO 5 5 8 530 283 6 6 8 530 280 7 7 8 532 295 8 8 8 532 283 A 8 540 105 (comparison) B 8 534 I00 (comparison) C 8 520 (comparison) D 8 544 (comparison) The spectral sensitivity is represented by a relative sensitivity which is obtained by supposing that the spectral sensitivity of the sensitizing dye (B) is 100 when exposed to light using a yellow filter.

The sensitizing dyes used for comparison are those having the following chemical structure. 4

(D) sH;

V The FIGURE shows curves of the spectral sensitivity of the silver halide emulsions containing sensitizing dye 7 which is the typical example of the sensitizing dyes used in the present invention (shown as the solid line) and sensitizing dye for comparison (A) (shown as the dotted line).

As being clear from the table and the FIGURE, it will be understood that the sensitizing dyes used in the present invention form the J-aggregate, and the photographic emulsions containing said dyes have excellent photographic characteristics in that they have a high spectral sensitivity and an excellent sharp cut property in a long wave length side. Brief explanation of drawmg:

The FIGURE shows curves of the spectral sensitivity. In the FIGURE, (7) and (A) represent curves of the spectral sensitivity of photographic emulsions containing the sensitizing dye (7) used in the present invention and the dye used for comparison (A), respectively.

What is claimed is:

1. A silver halide photographic emulsion which contains at least a sensitizing dye represented by the following formula:

wherein Z, and Z each represent a group of nonmetallic atoms necessary to complete a benzene ring, and R, and R each represent an identical or different alkyl group.

2. An emulsion as claimed in claim 1 wherein the alkyl group of R, or R is an alkyl group containing a sulfo or carboxy radical.

3. An emulsion as claimed in claim 1 wherein the benzene ring of Z, is substituted by the chlorine atom.

awa (I

Claims

2. An emulsion as claimed in claim 1 wherein the alkyl group of R1 or R2 is an alkyl group containing a sulfo or carboxy radical.
3. An emulsion as claimed in claim 1 wherein the benzene ring of Z1 is substituted by the chlorine atom.
4. An emulsion as claimed in claim 1 wherein the silver halide is silver iodobromide.
5. A light-sensitive silver halide photographic material which comprises a layer containing the silver halide emulsion as claimed in claim 1.
6. An emulsion as claimed in claim 1, wherein the sensitizing dye is selected from the group consisting of:
7. An emulsion as claimed in claim 1 wherein the alkyl group is a member selected from the group consisting of unsubstituted alkyl having up to 8 carbon atoms, hydroxyalkyl, acetoxyalkyl, carboxyalkyl, cyanoalkyl, carbamoylalkyl, sulfamoylalkyl, aminosulfonylalkyl, sulfoalkyl, aralkyl and allyl.
8. An emulsion as claimed in claim 1 wherein said alkyl group is a member selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, cyclohexyl, Beta -hydroxyethyl, gamma -hydroxypropyl, Beta -acetoxyethyl, gamma -acetoxypropyl, carboxymethyl, Beta -carboxyethyl, gamma -carboxypropyl, delta -carboxybutyl, p-carboxybenzyl, p-carboxyphenethyl, Beta -cyanoethyl, gamma -cyanopropyl, delta -cyanobutyl, Beta -carbamoylethyl, gamma -carbamoylpropyl, delta -carbamoylbutyl, Beta -N-ethylcarbamoylethyl, gamma -N-ethylcarbamoylpropyl, delta -N-methylcarbamoylbutyl, gamma -sulfamoyl propyl, delta -sulfamoyl butyl, gamma -N-ethylaminosulfonyl propyl, delta -N-ethylaminosulfonyl butyl, Beta -sulfoethyl, gamma -sulfopropyl, gamma -sulfobutyl, delta -sulfobutyl, p-sulfobenzyl, p-sulfophenethyl, benzyl, phenethyl, and vinylmethyl.