US3849147A

US3849147A - Silver halide supersensitized photographic emulsion

Info

Publication number: US3849147A
Application number: US00322581A
Authority: US
Inventors: K Shiba; A Sato
Original assignee: Fuji Photo Film Co Ltd
Current assignee: Fujifilm Holdings Corp
Priority date: 1969-06-25
Filing date: 1973-01-10
Publication date: 1974-11-19
Anticipated expiration: 1991-11-19

Abstract

A silver halide photographic emulsion is super-sensitized in the green wave length region by adding thereto at least one sensitizing dye of the following formula I and at least one sensitizing dye of the following formula II; and, optionally a compound of the following formula III:

The substituents are described in detail hereinbelow.

Description

llite ties Shiba et a1.

atent 91 [451*Nov. 19, 1974 SILVER HALIDE SUPERSENSITIZED PHOTOGRAPIIIC EMULSION [75] Inventors: Keisuke Shiba; Akira Sato, both of 'Kanagawa, Japan [73] Assignee: Fuji Photo Film Co., Ltd.,

Kanagawa, Japan Notice: The portion of the term of this patent subsequent to Feb. 27, 1990, has been disclaimed.

[22] Filed: Jan. 10, 1973 211 App]. No.: 322,581

Related US. Application Data [63] Continuation-impart of Ser. No. 49,981, June 25,

1970, Pat. No. 3,718,475.

[30] Foreign Application Priority Data Primary Examiner-J. Travis Brown Attorney, Agent, or Firm-Sughrue, Rothwell, Mion, Zinn & Macpeak [57] ABSTRACT A silver halide photographic emulsion is supersensitized in the green wave length region by adding thereto at least one sensitizing dye of the following formula I and at least one sensitizing dye of the following formula II; and, optionally a compound of the following formula III:

Formula l R1 R2 If N a 1') v-l 4 Formula II R5 (Km-l i Formula III The substituents are described in detail hereinbelow.

15 Claims, 12 Drawing Figures SHEET 10F 2 E :7? FIG I i i WAVE LENGTH (m l 5 FIG. 2 g

E I g 450 500 550 600 wAyE LENGTH (m FIG. 3 I

| 4 l I l 360 400 440 480 550 so e00. 640 680 720 760 800 WAVE LENGTH (m 360 460 440 450 550 so 660 640 eo (i0 7o s60 WAVE LENGTH (m zo 460 450 450 5:50 5 60 600 e30 650- 7'20 ro s60 WAVE LENGTH (m )0 FIG. 6

| I l I I I 360 400 440 480 520 560 660 640 700 720 760 800 WAVE LENeTH (m v PATENTE- 313V 1 8 I974 SHEET 2 OF 2 HGT FIG. 9

500 550 WAVE LENGTH (mp) SEQ 552mm :55

WAVE LENGTH (mu) 500 550 WAVE LENGTH (mp) 500 WAVE 'LENGTH EH58 CSEwzmw $2 5 FIG I0 WAVE LENGTH (mu) H6 II FIG. I2

WAVE LENGTH (mp) SILVER I-IALIDE SUPERSENSITIZED PHOTOGRAPHIC EMULSION CROSS-REFERENCE TO RELATED APPLICATIONS The present application is a continuation-in-part of Ser. No. 49,981 filed June 25, 1970, now US. Pat. No. 3,718,475.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a super-sensitized silver halide photographic emulsion and more particularly it relates to a super-sensitized silver halide photographic emulsion for increasing particularly the spectral sensitivity in the green region. Furthermore, the invention relates to a super-sensitized silver halide photographic emulsion containing couplers for making color photographic light-sensitive materials.

2. Description of the Prior Art It is well known that a spectral sensitizing method is one of the techniques employed in the manufacture of silver halide photographic emulsions, and that the sensitizing method is an indispensible technique for the production of color photographic light-sensitive materials. The spectral sensitivity obtained by the method is influenced not only by the chemical structure of the sensitizing dye to be used and the properties of the silver halide emulsion to be used, such as the composition of the halogen and the crystal system of the silver halide contained in the emulsion, the manner of chemical ripening, the silver ion concentration and the hydrogen ion concentration of the emulsion, but also by the various kinds of additives added to the silver halide emulsion.

In many cases, the spectral sensitivity is reduced. However, when a certain kind of sensitizing dye is used together with a dye or a colorless aromatic compound having a specific chemical structure according to the chemical structure and the properties of the sensitizi ng dye, a higher spectral sensitivity is obtained than when using each of the sensitizing dyes alone. This is known as a super-sensitizing action.

In particular, silver halide emulsions used for producing color photographic light-sensitive materials contain a large amount of couplers, and when a coupler is incorporated in a silver halide photographic emulsion containing a sensitizing dye, the spectral sensitivity becomes lower than the spectral sensitivity obtained by using the sensitizing dye alone. In addition, the presence of the coupler reduces the super-sensitizing action.

Also, the spectral sensitivity distribution in the green region. in which mans visual sensitivity is high, is one of the most important factors for the color reproduction of color photographic light-sensitive materials and for the quality of the image obtained.

Therefore, various studies have been made concerning the sensitization of silver halide emulsions in the green region. For example, a method of using a combination of a benzimidazolocarbocyanine dye and a pseudocyanine dye is described in the specification of US. Pat. No. 2,701,198. However, when the method described in the aforementioned US. patent is applied to a silver halide emulsion containing a coupler, only a lower sensitivity is obtained due to the presence of the coupler in the emulsion.

Also, a method of using a combination of a benzimidazolo carbocyanine dye and a benzoxazolocarbocyanine dye is described in the specification of slapanese Pat. Publication No. 4936/68. However, this method has the disadvantages that the sensitivity in the shorter wave length side of the green region, e.g., llIl a wave length region of 500-530 my. is large, and-also the contamination effect by thedyes after development is large.

Therefore, a primary object of the present invention is to provide a silver halide photographic emulsion having both a high spectral sensitivity in a wave length re gion of 500530 my and less of a contamination by the dyes after development.

Another object of the present invention is to provide a silver halide photographic emulsion used for producing a color photographic light-sensitive material having a high green sensitivity in the presence of a coupler.

SUMMARY OF THE INVENTION The above objects of the present invention can-be attained by super-sensitizing a silver halide photographic emulsion with at least one sensitizing dye represented by the following formula I: v

wherein R and R which may be the same or different) each represents an alkyl group, an aryl group or a substituted alkyl group; R and R (which may be the same or different) each represents an alkyl group, an aryl group, asuasmreaark l group, a sulfoalkyl groups? (preferably) a substituted alkylgroup having a sulfo group of the formula: -alkyl-(R ),,-SO or I alk l-s03- wherein R is an atomic group and n is an integer of at least I, at least one of said R and R being a sulfoalkyl group or said substituted alkyl group having a sulfo group and the end carbon atom of the alkyl moiety of the sulfoalkyl group or said substituted alkyl group having a sulfo group forminga covalent bond with the nitrogen atom of the heterocyclic nucleus; Z, ahd 2 (which may be the same or different) each represents l fM-I l R wherein 2;, represents a non-metallic atomic group necessary to complete a substituted or unsubstituted heterocyclic nucleus of the Z-quinoline series; 2, represents a non-metallic atomic group necessary to complete a benzoxazole nucleus, a naphthoxazole nucleus, a benzthiazole nucleus, a benzselenazole nucleus, a naphthothiazole nucleus, or a naphthoselenazole nucleus, each being unsubstituted or substituted by an alkyl group, a

trifluoromethyl group, a halogen atom, an alkoxyl group or sulfoalkoxyl group; R and R, (which may be the same or different) each represents an alkyl group,

a substituted alkyl group having a sulfo group as defined above (in R and R other substituted alkyl groups or a sulfoalkyl group; at least one of said R and R being a sulfoalkyl group or said substituted alkyl group having a sulfo group except where the heterocyclic nucleus containing 2, has been substituted by a sulfoalkoxyl group; X represents an acid anion group of the type usually employed in cyanine dyes; and q is an integer of l or 2, q being 1 when the cyanine dye of formula ll forms an intermolecular salt.

Furthermore, it has been discovered according to the present invention that a particularly better result is obtained by incorporating a compound represented by the following formula ll in the above-mentioned silver halide photographic emulsion.

Formula. 111

wherein R represents an alkyl group or a substituted alkyl group; Z represents a non-metallic atomic group necessary to complete a substituted or unsubstituted heterocyclic nucleous of the benzimidazole series; and Z represents a phenyl group or a substituted phenyl group, such as a phenyl group substituted by alkyl groups, alkoxy groups, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS The Figures are spectograms showing the relative sensitivity (i.e., speed) of various-photographic films employing super-sensitizing dye combinations according to the present invention as well as prior art combinations and individual dyes alone.

DETAILED DESCRIPTTONV OFITHQE PREFERRED EMBODIMENTS As stated above, at least one of R and R, is a sulfoalkyl group or, preferably, said substituted alkyl group having a sulfo group of the formula indicated. The atomic group represented by R may be, for example, an alkoxy group, an alkylamino group, an alkoxyamino group or a thioalkoxyl group and, preferably, n is a positive integer of up to 2.

The end carbon atom of the alkyl group (i.e., the -C" in CH CH CH SO forms a covalent bond with the nitrogen atom of the heterocyclic nucleus.

Typical examples of the preferred R and R groups are: sulfoalkoxyalkyl groups, sulfoalkoxyalkoxyalkyl groups and sulfohydroxyalkyl groups (i.e., -alkylalkoxy-SO -alkoxy-alkoxyalkoxy-SO; and

- sui IsE In the above-mentioned formulae 1 and ll,the alkyl groups of R to R include: methyl, ethyl, n-propyl, isopropyl, n-butyl and iso-butyl groups; and as the substituted alkyl groups of R to R there may be illustrated: an allyl group, an aralkyl group, a B -acetoxy-ethyl group, a -acetoxypropyl group, a y -carboxypropyl group, a B -carboxyethyl group, a y -sulfatopropyl group, a 8 -sulfatobutyl group, a 8 -N-acetylsulfamyl butyl group and a ,B-hydroxyethyl group.

Examples of the sulfoalkyl group of R R are a B-sulfopropyl group, a fi-sulfobutyl group or a fi-sulfobutyl group;

Examples of said substituted alkyl group having a sulfo group of R and R are a 2-(3-sulfopropoxy)ethyl group, a 2-[2-(3-sulfopropoxy) ethoxy]ethyl group, and a 2-hydroxy-l-sulfopropyl group.

As the benzimidazole series nucleus completed by Z Z or Z there may be illustrated: benzimidazole and benzimidazole containing, as a component of the skeletal-structure thereof, a benzene ring substituted by at least one of the following: a halogen atom, an N- unsubstituted or alkyl substituted sulfamyl or carbamyl group, an N-disubstituted sulfamyl group such as a morpholino sulfonyl group, an alkyl sulfonyl group, a trifluoromethyl group, an unsubstituted or substituted alkyl group, the substituent being an aralkyl group (e.g., benzyl) or a carboxyalkyl group (e.g., carboxymethyl), a cyano group, a phenyl group, a carboalkoxyl group, a'hydroxyl group, and an alkoxyl group.

Also, the 2-quinoline series nucleus completed by 2;, in the above-mentioned formula ll may be, for example, 2-quinoline and 2-quinoline containing, as a component of the skeletal-structure thereof, a benzene ring substituted by at least one of the following: an alkyl group and a halogen atom.

The substituted alkyl group R in the abovementioned formula III is, for example, a sulfoalkyl group neutralized by a cation, such as alkali metal ions,

1 organic ammonium ions, a pyridinium ion, a benzylthiouronium ion, and the like, i.e., a cation of the type usually employed in cyanine dyes, a cyanoalkyl group and an allyl group,

As X, and X in the formulae 1 and ii, there may be illustrated e.g., a halogen, perchlorate, thiocyanate, p-

.toluene sulfonate, benzene sulfonate, methyl sulfate and ethyl sulfate ions.

The sensitizing dye represented by formula ll ham least one sulfo group in the heterocyclic nucleous containing Z or at R or R The spectral sensitizing obtained by using the sensitizing dye represented by formula l] (i.e.. a monomethine cyanine dye) is ordinarily reduced by the introduction of a sulfo group therein. Therefore. it is quite surprising that when the sensitizing dye represented by formula I is used together therewith, the spectral sensitization is increased.

The sensitizing dye represented by the formula [I may be substituted therein by an alkyl group, a phenyl group, a halogen atom, an alkoxyl group, or an alkoxyl group substituted by at least a sulfo group; in other words, the substituent is so selected that the maximum sensitivity obtained by using at least one sensitizing dye of formula II and at least one compound of formula I in combination does not shift to a longer wave length side than that of the sensitizing dye of formula I].

The compound represented by formula lll shows a super-sensitizing action to the sensitizing dye represented by formula I and to the sensitizing dye represented by formula ll, and by using the compound represented by formula II] together with the combination of the other two sensitizing dyes. the green sensitivity is further increased and at the same time the sensitivity in the wave length region of 500-530 mu, which is pres ent at a shorter wave length side of the green region, is further increased.

The compounds which may be used in the present invention will be further illustrated by reference to the following illustrative formulae, which are merely illustrative, and not limiting, in nature.

(IIL) s F, -CH=C (CH1)3SO3' (CH S03N8.

I (I M) s\ CH3 C-CH III 2115 9Z i.Mm, S

CII-C N om zHs N (lHzhSOr O (H HaC- /S (HQsSOg' (IIIA) $zH5 o=on cn=r-r Cl N JzHs (IIIB) 12m C=CH CH= Q N 412115 1110 I ZHG N\ I C1- /c=o'H-o11=N@-0 CH3 Cl N g (HzhSOaNfi The above-mentioned sensitizing dyes or the other compounds which may be used in this invention may be synthesized by known methods.

For instance, they can be synthesized by the methods described in the specifications of US. Pat. Nos.

- 2,503,776 and 2,778,823; Belgian Pat. Nos. 590,607;

a water-soluble organic solvent such as methanol, ethanol, and pyridine. The sensitizing dyes represented by formula 1 and formula ll, respectively, may be addedto a silver halide emulsion as a mixture of the solutions thereof or as separate solutions. The amounts of these dyes are greatly influenced by the nature of the silver halide emulsion to be used. usually, the total amount of the above-mentioned sensitizing dyes (I and II) and compound III are preferably from 1 X 10 mol to l X 10 mol, per mol of silver halide. The weight ratio of the amount of the sensitizing dye represented by formula ll to the amount of the sensitizing dye represented by formula 1 is preferably from 10:1 to 1:2, but this ratio is varied by the amount, 1/10 to 5 times by mole based on dye l, of the compound represented by formula lll to be added.

As the silver halide emulsion which may be used in this invention, there may be illustrated: a silver iodobromide emulsion, a silver bromide emulsion, a silver chlorobromide emulsion, etc. The silver halide emulsion used in this invention is mainly a gelatino silver halide emulsion but the emulsion may contain, besides gelatin, polyvinyl alcohol, an alginic acid polymer, polyvinyl imidazole, polyvinyl pyrrolidone, or copolymers thereof. or may be an emulsion thereof.

The silver halide emulsion of this invention is applied to a suitable support according to the desired use, such as a paper, a glass plate, a cellulose triacetate film, a polyethylene terephthalate film, other plastic films than above, a baryta-coated paper, a resin-coated paper, or a synthetic paper.

The present invention will be illustrated further by the following examples which are merely illustrative and not limited in nature.

EXAMPLE 1 50 g of 1-pheny1-3-[3-(2,4-ditertiaryamylphenoxyacetamido )-benzamido]5- pyrazolone was dissolved in 100 ml of dibutyl phthalate by heating and the resultant solution was added to 1 liter ofa percent aqueous gelatin solution. Then, 50 ml ofa 5 percent aqueous solution of sodium alkylbenzene sulfonate was added thereto and they were dispersed by emulsification by means of a high speed rotary mixer (the product is called the dispersion of the magenta coupler).

1 kg. of a silver iodobromide emulsion (containing 0.25 mol of silver and 4.0 mol percent of iodine) prepared by a conventional method was placed in a beaker and melted at 40C. After adding to the emulsion the sensitizing dye in the amounts shown in Table l, the emulsion was stirred for minutes. Further, 400 g. of the dispersion of the magenta coupler as prepared above was added to the emulsion with stirring and after adding further suitable amounts of a hardening agent and an ampholite surface active agent as a wetting agent to the mixture with stirring, the resultant mixture source. The stript h us exposed was developed for 12 minutes at C in a color developer having the following composition:

N,N-diethy1-p-aminoaniline sulfate 29 g Sodium sulfite 2.0 g Sodium carbonate monohydrate 50.0 g Hydroxylamine hydrochloride 1.5 g Potassium bromide 1.0 g Water to make 1000 ml (pH, 10.3 i 0.1)

Thereafter, the strip was further processed in a first fixing solution, a bleaching solution and a second fixing solution and washed with water to obtain a magenta image. After drying the sample strips thus processed, the green filter density was measured by using an S-type Densitometer made by Fuji Photo. Film Co., from which characteristic curves were obtained. From these results, the densities at the point of fog plus 0.20 were calculated and the results are shown in Table l.

The compositions of the bleaching solution and the fixing solution used in the above processing were as follows:

Composition of the Bleaching Solution Fcrricyanide 100 g Potassium bromide 20 g Water to make 1000 ml (pH. 6.9 10.3) Composition of the Fixing Solution Hypo 200 g Sodium sulfite 20 g Acetic acid (28%) 45 ml Boric acid 7.5 g Potassium alum 20 g Water to make 1000 ml (pH. 4.5 x 0.2)

TABLE l Dyc Amount (m1) Dyi: Amount (ml) (A) (B) (mol conccn- (mol concentration) tration) (IA) 40(5Xl0") 115 0.17 120 0.23 40 (11C) 20(1Xl0'" 142 0.18 do. 40 165 0.20 do. 120 158 0.23 40 43 0.1 l 120 50 0.12 (1H) 49(5X10) 0.13 80 100 0.15 40 (11A) 40(IX10") 200 0.25 do. 80 186 0.25 40 35 0.13 80 35 0.13 40 (11B) 40( l 10"") 220 0.21 do. 80 282 0.25 40 43 0.13 80 46 0.13 40 (11D) 40( 1X10") 190 0.23 do. 80 220 0.25 40 33 0.11 80 35 0.12 (1C) 40(5X10) 0.13 80 105 0.15 40 (NE) 40(5X10) 200 0.19 do. 80 220 0.20 do. 160 220 0.22 40 45 0.18

80 50 0.17 160 58 0.15 40 (11F) 20( IXIO') 252 0.24 do. 40 282 0.27 do. 80 218 0.26 20 50 0.22 40 60 0.22 80 60 0.22 (IE) 40(5X10) 0.18 80 0.24 40 (I10) 40(1Xl0'") 200 0.20 do. 80 234 0.21 40 25 0.17 80 25 0.18

(ID) 40(IXIO) 80 118 0.14 40 (IIH) 40(5X10") 250 0.17 do. 80 316 0.20 40 33 0.15 80 40 0.15 (1C) 40(5X100") 100 0.15 80 115 0.22 40 (11B) 40(1X10'") 200 0.20 do. 80 220 0.25 (IF) 40 79 0.25 80 85 0.27 40 (11C) 20(1X10') 118 0.27 do. 40 0.30

(A): Relative yellow filter sensitivity (Sy) (B): Fog.

EXAMPLE 2 As in Example 1, 1 kg of a silver iodobromide emulsion (containing 0.30 mol of silver and 6.0 mol percent of iodine) was melted in a beaker at 40C and the amounts of the sensitizing dyes l and II and the compound of formula 111 shown in Table 2 were added to the emulsion with stirring. 7 ml of the silver halide emulsion thus obtained was applied to a glass plate of cabinet size followed by drying to obtain a sample.

The sample was cut into strips and the strips were subjected to an optical wedge exposure by yellow light Kl2, made by Fuji Photo Film Co.. Ltd. employing a sensitometer having a light source of 5.400K in color temperature. The exposed strips were then developed for 10 minutes at 200C in a developer having the folas in Example 1 and then developed in a developer hav- 5 lowing composition: ing the following composition for minutes at 20C.

Composition of the Developer Water 500 ml Metol 0.3 g Composition of the Developer 10 Sodium pyrosulfite 38 g Hydroquinone 6 g Water 500 ml Sodium carbonate monohydratc 22.5 g Metol 0.3 g Citric acid 0.7 g Sodium pyrosulfite 38 g Potassium bromide 0.9 g Hydroquinone 6 g Water to make 1000 ml Sodium carbonate monohydrate 22.5 g Citric acid 0.7 g Potassium bromide 0.9 water to make ml The strips were then fixed and the optical densities thereof measured. in addition, the fog values of the developed strips were also measured.

The structure of the dyes employed are shown here- The strips were then fixed and the optical densities inbelow. and the amounts of the various dyes in each thereof were measured, the results of which are shown samples as well as the measured sensitivity and fog valin Table 2. ues are shown in Table 3 below.

TABLE 2 Dye Amount (ml) Dye Amount (ml) Compd Amt (ml) A B (mol concen- (mol concen- (mol concentration) tration) tration) lB 406x10") 100 0.15 do. 80 do. 97 (H6 do. 40 do. "8 40(1x10') 142 0.15 do. do. do. 80 do. I78 0.]6 do. do. do. do lllA 20 1 10-1 166 0.15 do. do. do. do. do. 40 do. 200 0.l5 do. do. do. do. do. do. 200 016 do. do. do. do. "1B 401 1x10-) 178 0. 16 do. do. do. do. do. 80 do 190 0.16 do. do. do. do. lllC 40 1x10) 190 0.16 do. do. do. do. do. 80 do. 200 0.17

(A): Relative yellow filter sensitivity (Sy) ival-0g Table 3 Dyes Dyes Yellow Filtered Relative Fog Spectrogram ml (mole concentration) ml (mole concentration) Sensitivity (1B) 80 (5 X10) 0.11 96 0.12 (A) 40 (5 x10) 79 0.11 80 84 0.12 I60 69 0.14 (1H) 80 2 x 10- 33 0.10 160 33 0.10 (B) so 2 x 10- 47 0.11 160 47 0.11 (1B) 80 5 x10") (1U) 40 2 x10-) 211 0.09

so 80 225 012 FIG. 1 curve 1 (A) so (5 x10) (B) 40 (2 x10) 157 0.12

80 so 157 0.16 FIG. 2 curve 2 7 Dye A .WJEXSMPPE 3 32m om. A silver bromoiodide emulsion was prepared by a 55 C 01 conventional method such that one kilogram of the re- C CH:cH CH=C sulting silver halide emulsion had a silver content of 0.6

. Cl C1 mole and an iodide content of 6.0 mole percent. Varlt; N ous samples were made by the followtng procedure. 60 e $2115 One kilogram of the above-produced silver bromoiodide emulsion was weighed into a beaker and melted in Dye B a water-bath at 40C. To the melted emulsion, certain s amounts of sensitizing dyes were added with stirring, the amounts and type of dyes being shown in the table below. Seven milliliters of the resulting emulsion were 65 weighed and coated onto a cabinet size glass plate to obtain samples.

Each sample was cut into strips and subjected to an optical wedge exposure through a yellow filter, No.

EXAMPLE 4 As in Example I. 1 kg ofa silver iodobromide emulsion containing 0.52 mol of silver and 7 mol percent of iodine wherein an average grain diameter of the silver EXAMPLE A silver bromoiodide emulsion was prepared by a inbelow, and the amounts of the various dyes in each halide is 078 M was weighed into a beaker and melted 5 conventional method such that one kilogram of the rein a bath at and amounts of the sensitizing sultmg silver hal de emulsion had astlver content of 0.0 dyes and shown in Table 4 added to the emu] mole and an iodide content of 6.0 mole percent. Varision. To the resulting emulsion there were added ml Ous Samples were made by the fellowmg Procedureof 1 percent y aqueous 50mm)" of sodlum 10 One kilogram of the above-produced silver b romoiog q -f q a ff ml of a lzzbpercem dide emulsion was weighed into a beaker and melted in t g i z 9 q' enzene a water-bath at 40C. To the melted emulsion, certain g z g r i g g g' as amouunts of sensitizing dyes were added with stirring, g i zg f 3 i if to E i T ness 0 the amounts and type of dyes being shown in the table The Sam '6 was cut int Sm S and 3 8 t a below. Seven milli liters of the resulting emulsion were p O p J O n weighed and coated onto a cabinet size glass plate to opt1cal wedge exposure through a yellow filter accordobtam samples. mg to Example I. The str1ps were then developed and 7 V H g fixed, and the optical densities thereof were measured Baal Sample was Cut SHIPS and subleeted to an according to Example 2,the results ofwhich are shown op ical we g xposur hrough a y low fi r. N0. in Table 4 below. K-l2, made by Fuji Photo Film Co., Ltd. employing a In addition, spectrograms were obtained according to sensitometer having a light source of 5,400l( in color conventional procedures by means of a spectrophotemperature. The exposed strips were then developed tometer having a light source of 2,666K and a reflecfor 10 minutes at 200C in a developer having the foltion type-defraction lattice. lowing composition:

7 Table 4 Dye Amuunt(ml) Dye Amount(ml) Dye (Mol Conccnt- Dyc (Mol Concent- (A) (B) spectrogram ration) ration) 80 80 0.06 FIG. 3 curve l (11K) 80 1 x 10*) 32 0.08 I 40 0.06 do. 2 (1B) 5 x10) (HK) 80 I38 0.09

do. 160 I60 0.10 do. 3 (ML) 80 (1 x 10-" 89 0.10 FIG. 4 curve 4 I60 96 0.14 ([8) s0 5 x 10*) (11L) 80 152 0.09 do. 5

(NM) 80 (l X 10"") 63 0.07 FIG. 5 curve 6 160 63 0.10 ("3) 80 (5x10*) (NM) 80 178 0.11 do. 7

(D) 80 (l X IO) 44 0.06 FIG. 6 curve 8 160 44 0.11 (I8) 80 (D) 80 117 0.08 do. 9 -(A) 80 (D) 80 112 0.36 do. 10 (ID) 40 5 x 10") 0.07 FIG. 11 curve 11 so 1 12 008 ("N1 80 1 x 10-=) 32 0.06 I60 32 006 (ID) 80 (5 x 10") (no) 80 1 x 10*) 010 FIG. 11 curve 12 do. I60 200 0.12 H8) 80 (5 x10") (UN) 80 1 x 10*) 160 0.10 FIG. 12 curve 13 do. 160 178 0.10 (1101 80 (1 x 10*) 40 0.08 160 62 0.08

Dyes A and D shown in Table 4 have the following Cvmpusilion Ofthe Developcr structures: A water 500 m] Metol 0.3 g (A) 02H (ljzHi Sodium pyrosulfitc 38 g N 55 Hydroquinonc 6 g Sodium carbonate monohydratc 22.5 C1 C1 Citric acid 0.7 g

I %CCH=CHCH=C Potassium bromide 0.9 g C1 C1 Water to make I000 ml 0.11. 5.11. 60 (D) The strips were then fixed and the optical densities CH3 thereof measured. ln addition, the fog values of the developed strips were also measured. \fi The structure of the dyes employed are shown here- & OCH: 65

( lzHs sample as well as the measured sensitivity and fog values are shown in Table 5 below.

TABLE Dyes Dyes Yellow filtered Relative Fog spectrogram ml (mole concentration) ml (mole concentration) Sensitivity (1B) 80 (5X10") 100 0.12 160 95 0.13 (A) 40 (5)00") 79 0.11 80 84 0.12 l60 70 0.13 (11.1) 80 (2Xl0 32 0.10 160 32 0.10 (B) 80 (ZXIO' 47 0.10 160 47 0.10 (113) 80 (5XIO) (11.1) 40 (ZXIO 210 0.10

80 (5Xl()) 80 225 0.12 FIG. 7 curve 1 (1B) 80 (5XIO"') (B) 40 (2XI0 166 0.10

80 (5X10) 80 166 0.11 FIG. 7. curve 2 (A) 80 (5)00) (11.!) 40 (ZXIO' 132 0.09 FIG. 8. curve 3 80 (5X10") 80 157 0.11 (A) 80 (5X10 (B) 40 (ZXIO 158 0.12 FIG. 8. curve 4 EXAMPLE 6 image. The compositions of the bleaching solution and fixing solution are shown in Example 1. After drying A Silver bromoiodide emulsion was Prepared as each sample strip as processed above, the green filter forth in Example 5 above, and various amounts of the density was mwsured employing an S type d i Same y in the Same amounts as shown Table 6 ter made by Fuji Photo Film Co., Ltd., from which the were added 10 different emulsiohs- To each 1 characteristic curves of each sample were obtained. sensitized silver bromoiodide emulsion was added, with F these results h d i i at th point f f l stirring, 600 grams of the magenta coupler dispersion 0.20 were calculated and the results are shown in Table described in Example 1. To each of the reulsting emul- 6 b l w;

TABLE 6 Dyes Dyes Yellow Filtered Relative Fog spectrogram ml (mole concentration) ml (mole concentration) Sensitivity (IE) 80 5x10-*) 89 0.13 160 96 0.11 (A) (5x10-*) 0.10 89 0.11 I60 89 0.14 (111) 80 (2 10-- 25 0.11 160 27 0.11 (B) 80 2x10- 0.10 I60 0.11 (lB) 80 (5x10-*) (111) 40 2x10- 170 0.11 no.9

80 (5x 220 0.14 Curve 5 (1B) 80 5x10-) (B) 40 2 10-") 0.11 no.9

80 5x10-) 80 95 0.11 Curve 0 (A) 80 5x10- (111) 40 2x10- 0.11 FIG. 10 80 (5x10-*) 80 142 0.21 Curve 7 (A) 80 5x10-* (B) 40 2x10- 74 0.11 FIG. 10 so (5x10-*) s0 77 0.11 Curve 8 'difficult to determine a sensitivity sions were added a hardening agent and an anionic surwh i l im d i face-activating agent, as is conventional, and the result- 1, A super-sensitized silver halide photographic lng emulsions were coated onto a Cellulose tl'iacelale emulsion wherein the light-sensitivity in the wavelength film base to Obtain green-Sensitive Photographic mate" 0 region of 5005 30 mp. is increased containing at least rials. The resulting samples were cut into strips and one fi iti i d represented by thefollowing LII subjected to an optical wedge exposure through a yelf l 1;

low filter, No. K-12, made by Fuji Photo Film Co.,

Ltd., employing a sensitometer whose light source had R1 Fmmulal R2 a color temperature of 5,400K. Each exposed strip was 55 1 I developed for 12 minutes at 20C in a color developer having the following composition: C CH:CH CH:C I

N.N-dtcthyl-p-aminoanllinc sulfate 2.0 g N N Sodium sulfite 2.0 g 60 I l Sodium carbonate monohydratc 50 g R3 (X1')1 1 R4 Hydroxylaminc hydrochloride g pmsmm bromide 1.0 g wherem R, and R which may be the same or different, Water to make 1000 ml uni nix 0,1) each represents an alkyl group, an aryl group or a sub- 65 stituted alkyl group with the substituent being vinyl,

Thereafter, each strip was further processed in a first aryl, acetoxy, carboxy, sulfato, N-acetylsulfamyl or hyfixing solution, a bleaching solution and a second fixing dr xy; R3 and 4, Which m y be the Same different, solution and washed with water to maintain a magenta each represents an alkyl group, a substituted alkyl group with the substituents being the same as in the substituted alkyl group of R and R an aryl group, a sulfoalkyl group or a substituted alkyl group having a sulfo group of the formula alkyl-(BlahI-SOr Or-alkyI-SO wherein R represents an atomic group and n is an integer of at least I; at least one of said R and R being sulfoalkyl or said substituted alkyl group having a sulfo group, the end carbon atom of said sulfoalkyl group or said substituted alkyl group having a sulfo group forming a covalent bond with the nitrogen atom of the het- 15 erocyclic nucleus; Z and Z which may be the same or different, each represents a non-metallic atomic group necessary to complete a heterocyclic nucleus of the benzimadazole series, said nucleus being unsubstituted or substituted with halogen, an N-unsubstituted or alkyl-substituted sulfamyl or carbamyl group, an N- disubstituted sulfamyl group, an alkyl sulfonyl group, a trifluoromethyl group, an alkyl group, a substituted alkyl group wherein the substituent is an aryl group or a carboxyl group, a cyano group, a phenyl group, a carboalkoxyl group, a hydroxyl group or an alkoxyl group; X, represents an acid anion group and p is an integer of l or 2, being 1 when the dye of formula I forms an intermolecular salt; and at least I second sensitizing dye represented by the following formula II:

wherein 2;, represents a nonmetallic atomic group nec essary to complete a substituted or unsubstituted heterocyclic nucleus of the 2-quinoline series wherein the substituent is alkyl or halogen; Z represents a nonmetallic atomic group necessary to complete a benzoxazole nucleus, a naphthoxazole nucleus, a benzthiazole nucleus, a benzselenazole nucleus, 21 naphthothiazole nucleus or a naphthoselenazole nucleus, each of said nuclei being unsubstituted or substituted by an alkyl group or a trifluoromethyl group, a phenyl group, a halogen atom, an alkoxyl group or an alkoxyl group having a sulfo group; R and R which may be the same or different each represents an alkyl group, a substituted alkyl group with the substituents being the same as in the substituted alkyl group of R, and R a sulfoalkyl group or said substituted alkyl group having a sulfo group; at least one of said R and R being a sulfoalkyl group or said substituted alkyl group having a sulfo group except where the heterocyclic nucleus completed by Z, has been substituted by a sulfoalkoxyl group; X; represents an acid anion; and q is an integer of I or 2, q being I when the dye of formula II forms an intermolecular salt.

2. A super-sensitized silver halide emulsion accord- 5 Ftll'lllllllt 1 ll wherein R represents an alkyl group or a substituted alkyl group wherein the substituent is a sulfoalkyl group neutralized by a cation, 21 cyano group or a vinyl group; 2 represents an atomic group necessary tocomplete a heterocyclic nucleus of the benzimidazole series, said nucleus being unsubstituted or substituted with halogen, an N-unsubstituted or alkyl-substituted sulfamyl or carbamyl group, an N-disubstituted sulfamyl group, an alkyl sulfonyl group, a trifluoromethyl group, an alkyl group, a substituted alkyl group wherein the substituent is an aryl group or a carboxyl group, a cyano group, a phenyl group, a carboalkoxyl group, a hydroxyl group or an alkoxyl group; and Z represents a phenyl group or a substituted phenyl group wherein the substituent is alkyl or alkoxyl.

3. a silver halide emulsion according to claim 1 wherein the alkyl group of R to R is methyl, ethyl, npropyl, iso-propyl, n-butyl or iso-butyl.

4. A silver halide emulsion according to claim 2.

wherein the alkyl group of R to R is methyl, ethyl, npropyl, iso-propyl, n-butyl or iso-butyl.

5. A silver halide emulsion according to claim 1 wherein said substituted alkyl group is a vinylmethyl group, a benzyl group, a B-acetoxyethyl group, a 'y-acetoxypropyl group, a y-carboxypropyl group, a B-carboxyethyl group, a 'y-sulfatopropyl group, a 6-sulfatobutyl group, a S-N-acetylsulfamylbutyl group, a B-hydroxyethyl group, a 'y-sulfopropyl group, a 'y-sulfobutyl group or a fi-sulfobutyl group, and wherein said substituted alkyl group having a sulfo group is a 2-(3-sulfopropoxy)ethyl group, a 2[2-(3-sulfopropoxy)ethoxy} ethyl group, or a 2-hydroxy-l-sulfopropyl group.

6. A silver halide emulsion as in claim 2 wherein the total amount of said sensitizing dyes I and Ii and said compound of formula III is within the range of from I x l0 mol to l X 10' mol per mol of silver halide.

7. A silver halide emulsion as in claim I wherein said emulsion contains one sensitizing dye of formula I and the following second sensitizing dye:

( zI-LNHC 0 0 130303 8. A silver halide emulsion as in claim 2 which contains a second sensitizing dye of the following formula:

JJZILNHC O CaHaSOa' at least one first sensitizing dye of formula I aridatleast one compound of formula III.

9. A photographic light-sensitive element comprising 21 a support having thereon at least one layer containing the photographic silver halide emulsion as in claim 1. 10. A silver halide emulsion according to claim 1 containing one sensitizing dye of formula I and the sec- 11. A silver halide emulsion according to claim 1 containing one sensitizing dye of formula I and the following q nd s n itizin d e 12. A silver halide emulsion according to claim 1 containing a sensitizing dye of formula I and a second sensitizing dye of the formula:

13. A silver halide emulsion according to claim 1 containing a sensitizing dye of formula I and a second sensitizing dye of the formula:

14. A silver halide emulsion according to claim 1 containing one sensitizing dye of formula ll and the following sensitizing dye:

wherein R and R have the same meaning as in claim 1.

15. A silver halide emulsion according to claim 1 containing one sensitizing dye of formula ll and the following sensitizing dye:

wherein R R R and R have the same meaning as in claim 1.

Claims

1. A SUPER-SENSITIZED SILVER HALIDE PHOTOGRAPHIC EMULSION WHEREIN THE LIGHT-SENSITIVITY IN THE WAVELENGTH REGION OF 500-530 MU IS INCREASED CONTAINING AT LEAST ONE FIRST SENSITIZING DYE REPRESENTED BY THE FOLLOWING FORMULA I:

2. A super-sensitized silver halide emulsion according to claim 1 wherein said silver halide emulsion further contains a compound represented by the following formula III:

3. a silver halide emulsion according to claim 1 wherein the alkyl group of R1 to R7 is methyl, ethyl, n-propyl, iso-propyl, n-butyl or iso-butyl.

4. A silver halide emulsion according to claim 2 wherein the alkyl group of R1 to R7 is methyl, ethyl, n-propyl, iso-propyl, n-butyl or iso-butyl.

5. A silver halide emulsion according to claim 1 wherein said substituted alkyl group is a vinylmethyl group, a benzyl group, a Beta -acetoxyethyl group, a gamma -acetoxypropyl group, a gamma -carboxypropyl group, a Beta -carboxyethyl group, a gamma -sulfatopropyl group, a delta -sulfatobutyl group, a delta -N-acetylsulfamylbutyl group, a Beta -hydroxyethyl group, a gamma -sulfopropyl group, a gamma -sulfobutyl group or a delta -sulfobutyl group, and wherein said substituted alkyl group having a sulfo group is a 2-(3-sulfopropoxy)ethyl group, a 2(2-(3-sulfopropoxy)ethoxy) ethyl group, or a 2-hydroxy-1-sulfopropyl group.

6. A silver halide emulsion as in claim 2 wherein the total amount of said sensitizing dyes I and Ii and said compound of formula III is within the range of from 1 X 10 6 mol to 1 X 10 3 mol per mol of silver halide.

7. A silver halide emulsion as in claim 1 wherein said emulsion contains one sensitizing dye of formula I and the following second sensitizing dye:

8. A silver halide emulsion as in claim 2 which contains a second sensitizing dye of the following formula:

9. A photographic light-sensitive element comprising a support having thereon at least one layer containing the photographic silver halide emulsion as in claim 1.

10. A silver halide emulsion according to claim 1 containing one sensitizing dye of formula I and the second sensitizing dye:

11. A silver halide emulsion according to claim 1 containing one sensitizing dye of formula I and the following second sensitizing dye:

12. A silver halide emulsion according to claim 1 containing a sensitizing dye of formula I and a second sensitizing dye of the formula:

14. A silver halide emulsion according to claim 1 containing one sensitizing dye of formula II and the following sensitizing dye:

15. A silver halide emulsion according to claim 1 containing one sensitizing dye of formula II and the following sensitizing dye: