Silver halide photographic element containing a gelatinous layer hardened with an aliphatic hydrocarbon having at least three vinylsulfonyl groups

A photographic element comprising a support and a gelatin-containing layer coated thereon which contains gelatin having been hardened with a compound having in the molecular structure an aliphatic hydrocarbon chain to which at least 3 vinyl sulfonyl groups are bonded.

This invention relates to a process for hardening photographic gelatin by 
use of a novel hardener, and particularly to a gelatin-hardening process 
suitable for hardening any gelatin-containing layer of a light-sensitive 
silver halide photographic material. 
Generally, light-sensitive silver halide photographic materials are 
prepared by forming on a proper support, such as glass, paper or synthetic 
resin film, various layers such as silver halide photographic emulsion 
layer, filter layer, inter layer, protective layer, sub layer, backing 
layer, anti-halation layer, etc., which can be called generically as 
photographic layer. These photographic layers consist of so-called gelatin 
films composed mainly of gelatin. Accordingly, the physical properties of 
the photographic layers consisting of gelatin films depend chiefly on 
those of gelatin. However, gelatin itself has such properties as being low 
in melting point, high in water swellability and low in mechanical 
strength. These properties are extremely undesirable as the physical 
properties of layers of light-sensitive silver-halide photographic 
materials. It has therefore been an ordinary practice hitherto that 
various hardeners are reacted with gelatin to crosslink the hardeners with 
amino, carboxyl, amide and the like functional groups in the gelatin 
molecules, thereby improving the physical properties of gelatin. As such 
hardeners, there have been known from old times inorganic hardeners 
comprising polyvalent metal salts such as chromium alum, chromium 
trichloride and the like chromium salts or aluminum salts, and organic 
hardeners such as formalin, glyoxal and acrolein and their derivatives. 
Photographically, however, these hardeners have various drawbacks, and 
most of them bring about many such disadvantages as, for example, they are 
strong in desensitizing action, promote the formation of fog, are too slow 
in hardening action to be put into practical use, disturb the color 
forming ability of couplers used in color emulsions, and are excessively 
rapid in hardening action to make the preparation of light-sensitive 
photographic materials difficult or, conversely, cannot display desired 
hardening effects unless incubated sufficiently. 
In order to meet quick processing of light-sensitive silver halide 
photographic materials which has been required recently, not only 
photographic materials themselves have been improved so as to be in 
conformity to quick processing, but also processing solutions have been 
improved so as to be suitable for treatment of such photographic 
materials. For example, in order to make quick penetration of processing 
solutions possible, photographic materials have been increased in amount 
of silver halide and decreased in amount of gelatin so as to be made 
thinner. Consequently, not only the photographic materials are increased 
in fog but also the film properties thereof are further deteriorated. 
Furthermore, with recent propagation of automatic processing machines, 
photographic materials are required to have film properties sufficiently 
high in mechanical strength so as to withstand severe mechanical abrasion. 
In addition, with the spread of high temperature-quick processing by use 
of strong processing solutions, photographic materials are required to 
have strong film properties which do not injure the photographic 
properties. Particularly, in the case of color films, not only the color 
development itself requires a longer time than in the case of 
black-and-white development, but also a bleaching treatment is required, 
in general. Further, in the case of reversal color treatment, the first 
development should necessarily be effected, so that photographic materials 
are required to be strong in film hardness. 
Accordingly, most of the conventional hardeners bring about disadvantages 
with progress of quick processing of light-sensitive photographic 
materials. For example, if only the amount of hardener is increased in 
order to obtain stronger physical properties of the gelatin film, not only 
the hardener causes increased desensitization and fogging but also the 
covering power is lowered. Even if the hardness of film is increased, the 
film becomes so brittle that the photographic material is difficulty 
subjected to an automatic processing machine. 
An object of the present invention is to provide a hardener which brings 
about no such disadvantages as mentioned above. 
Another object of the invention is to provide a process suitable for 
hardening photographic gelatin, particularly gelatin films of 
light-sensitive silver halide photographic materials, by use of the 
above-mentioned hardener. 
Still another object of the present invention is to provide a photographic 
element which comprises a support and a gelatin-containing layer coated 
thereon, the physical properties of which layer are improved without 
deteriorating the photographic properties of the photographic element. 
Such photographic elements include those having been subjected and not 
having been subjected to photographic treatment. 
These objects can be accomplished by using as the hardener a compound 
having in the molecular structure thereof an aliphatic hydrocarbon group 
to which at least three vinylsulfonyl groups have been bonded 
(hereinafter, the said compound will be referred to as the compound of the 
present invention). 
To use the above-mentioned compound as the hardener, referred to herein, 
means to react the said compound with gelatin in a stratiform gelatin 
which is a constitutive layer of light-sensitive photographic material. 
The said reaction may be carried out according to any of a process in 
which the compound is added to a coating liquid, which is then coated on a 
support and dried; a process in which the compound is previously reacted 
with gelatin, and the reaction product is added to a coating liquid, which 
is then coated on a support and dried; a process in which a coating liquid 
containing the compound is coated on a previously formed layer to form a 
layer, which is then dried; or a process in which a photographic material 
consisting of a support and photographic layers formed thereon is dipped 
in a solution of the compound either before or during the development of 
the photographic material. 
Typical examples of the compounds of the present inventon are shown below, 
but compounds usable in the present invention are not limited to these. 
Among the below-mentioned compounds those of the acid or base type can be 
used as salts thereof, and compounds in the form of such salts are also 
involved in the compounds of the present invention. Examples of the 
compounds are given below: 
##STR1## 
Typical procedures for synthesizing the compounds of the present invention 
are explained below with reference to synthesis examples, but these are 
not limitative. All the parts are expressed by weight. 
SYNTHESIS EXAMPLE 1 
(Synthesis of the exemplified compound 2) 
To 300 parts of ethanol were successively added 6.9 parts of metallic 
sodium, 23.4 parts of 2-mercaptoethanol and 18.9 parts of 
1,1,1-tris(chloromethyl)propane in this order, and the resulting mixture 
was heated under reflux. Thereafter, the deposited sodium chloride was 
removed, and the solution was concentrated to obtain 
1,1,1-tris(2-hydroxyethyl-thiomethyl) propane. This compound was added to 
50 parts of chloroform, and 45 parts of thionyl chloride was dropped into 
the resulting mixture. Subsequently, the mixture was heated under reflux, 
and then the solvent chloroform and unreacted thionyl chloride were 
removed by distillation under reduced pressure. The residual oily 
substance was poured into ice water and extracted with ether, and the 
ether extract was dehydrated over anhydrous sodium sulfate and then freed 
from the solvent by distillation to obtain 
1,1,1-tris(2-chloroethylthiomethyl)propane. To this compound were 
successively added 0.3 part of phosphoric acid and 60 parts of 30% aqueous 
hydrogen peroxide, and the resulting medium mixture was heated under 
reflux and then cooled to deposit 
1,1,1-tris(2-chloroethylsulfonylmethyl)propane. The deposited compound was 
recovered by filtration and dissolved in 200 parts of acetone, and the 
resulting acetone solution was incorporated with 30 parts of triethylamine 
and then stirred at room temperature to deposit triethylamine 
hydrochloride. This hydrochloride was removed, and the acetone solution 
was concentrated to deposit white solids. The solids were recrystallized 
from ethanol-acetone to obtain 1,1,1-tris(vinylsulfonylmethyl)propane. 
Elementary analysis for C.sub.12 H.sub.20 O.sub.6 S.sub.3 : 
______________________________________ 
C H S 
______________________________________ 
Calculated (%) 
40.43 5.65 26.99 
Found (%) 40.29 5.55 27.03 
______________________________________ 
SYNTHESIS EXAMPLE 2 
(Synthesis of the exemplified compound 5) 
To 300 parts of ethanol were successively added 6.9 parts of metallic 
sodium, 23.4 parts of 2-mercaptoethanol and 14.7 parts of 
1,2,3-trichloropropane in this order, and the resulting mixture was heated 
under reflux. Thereafter, the deposited sodium chloride was removed, and 
the solution was concentrated to obtain 
1,2,3-tris(2-hydroxyethylthio)propane. This compound was added to 80 parts 
of chloroform, and 45 parts of thionyl chloride was dropped into the 
resulting mixture. Subsequently, the mixture was heated under reflux, and 
then the solvent chloroform and unreacted thionyl chloride were removed by 
distillation under reduced pressure. The residual oily substance was 
poured into ice water and extracted with ether, and the ether extract was 
dehydrated over anhydrous sodium sulfate and then freed from the solvent 
by distillation to obtain 1,2,3-tris(2-chloroethylthio)propane. To this 
compound were successively added 0.3 part of phosphoric acid and 60 parts 
of 30% aqueous hydrogen peroxide, and the resulting mixture was heated 
under reflux and then cooled to deposit 
1,2,3-tris(2-chloroethylsulfonyl)propane. The deposited compound was 
recovered by filtration and dissolved in 100 parts of dimethyl sulfoxide, 
and the resulting solution was incorporated with 30 parts of triethylamine 
and then stirred at room temperature to deposit triethylamine 
hydrochloride. This hydrochloride was removed, and then the dimethyl 
sulfoxide was removed by distillation to deposit solids. The deposited 
solids were recrystallized from ethanol to obtain 
1,2,3-tris(vinylsulfonyl)propane. 
Elementary analysis for C.sub.9 H.sub.19 O.sub.6 S.sub.3 : 
______________________________________ 
C H S 
______________________________________ 
Calculated (%) 
33.84 5.99 30.12 
Found (%) 33.65 5.89 30.31 
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SYNTHESIS EXAMPLE 3 
(Synthesis of the exemplified compound 13) 
To 400 parts of ethanol were successively added 9.2 parts of metallic 
sodium, 31.2 parts of 2-mercaptoethanol amd 38.8 parts of pentaerythritol 
tetrabromide, and the resulting mixture was heated under reflux. 
Thereafter, the deposited sodium bromide was removed, and the ethanol was 
removed by distillation to obtain 
tetrakis(2-hydroxyethylthiomethyl)methane. This compound was added to 80 
parts of chloroform, and 60 parts of thionyl chloride was dropped into the 
resulting mixture. Subsequently, the mixture was heated under reflux, and 
then the solvent chloroform and unreacted thionyl chloride were removed by 
distillation under reduced pressure. The residual oily substance was 
poured into ice water and extracted with ether, and the ether extract was 
dehydrated over anhydrous sodium sulfate and then freed from the ether by 
distillation to obtain tetrakis(2-chloroethylthiomethyl)methane. To this 
compound were successively added 0.4 part of phosphoric acid and 80 parts 
of 30% aqueous hydrogen peroxide, and the resulting mixture was heated 
under reflux and then cooled to deposit 
tetrakis(2-chloroethylsulfonylmethyl)methane. The deposited compound was 
recovered by filtration and dissolved in 200 parts of acetone, and the 
resulting solution was incorporated with 40 parts of triethylamine and 
then stirred at room temperature to deposit triethylamine hydrochloride. 
This hydrochloride was removed, and the acetone was removed by 
distillation to deposit solids. The deposited solids were recrystallized 
from acetone-ethanol to obtain tetrakis(vinylsulfonylmethyl)methane. 
Elementary analysis for C.sub.13 H.sub.20 O.sub.8 S.sub.4 : 
______________________________________ 
C H S 
______________________________________ 
Calculated (%) 
36.10 4.66 29.65 
Found (%) 36.02 4.52 29.81 
______________________________________ 
In incorporating the thus synthesized compound of the present invention as 
hardener into photographic layers of a light-sensitive silver halide 
photographic material, the compound may be formed into a solution in one 
or more of water and common organic solvents such as methanol, ethanol, 
acetone, methyl ethyl ketone, ethyl cellosolve, methyl cellosolve, 
acetonitrile, dioxane, dimethylformamide, dimethyl sulfoxide, ethyl 
acetate, halogenated alcohol, chloroform, etc., and then added to a 
coating liquid for forming eqch of said layers. It is also possible to 
overcoat the said hardener solution on the uppermost layer of said layers. 
The amount of the compound of the present invention to be added to the 
coating liquid for forming gelatin film varies depending on the kind, 
physical properties, photographic properties, etc., of the objective 
gelatin film, but is ordinarily from 0.01 to 100% by weight, preferably 
from 0.1 to 10% by weight, based on the dry weight of gelatin in the 
coating liquid. The compound may be added at any stage during preparation 
of the coating liquid. To a silver halide emulsion for example, however, 
the compound is preferably added after second ripening of the emulsion. 
Light sensitive silver halide photographic materials, to which the present 
invention is applicable, include all such light-sensitive photographic 
materials as, for example, black-and-white, color and pseudocolor 
photographic materials, and ordinary, printing, X-raysensitive and 
radiation-sensitive photographic materials which may be any of negative, 
positive, direct-positive and the like types. 
Silver halide emulsions used in the abovementioned light-sensitive silver 
halide photographic materials may contain as sensitive components all 
kinds of silver halides such as silver chloride, silver iodide, silver 
bromide, silver iodobromide, silver chlorobromide, silver 
chloroiodobromide, etc. Further, these emulsions may be subjected to 
various types of chemical sensitization such as noble metal sensitization 
using salts of noble metals such as ruthenium, rhodium, palladium, 
iridium, gold, etc., e.g. ammonium chloropalladate, potassium 
chloroplatinate, potassium chloropalladite, potassium chloroaurate, etc., 
sulfur sensitization using sulfur compounds, selenium sensitization using 
selenium compounds, reduction sensitization using stannous salts, 
polyamides, etc., and sensitization using polyalkylene oxide type 
compounds, or to optical sensitization using cyanine, merocyanine and the 
like dyes. Further, the emulsions may be incorporated with couplers, 
stabilizers, e.g. mercury, triazole, azaindene, benzothiazolium and zinc 
compounds, wetting agents, e.g. dihydroxyalkanes, antistatic agents, film 
modifiers comprising water-dispersible, fine granular polymeric substances 
obtained by emulsion polymerization, coating aids, e.g. saponin and 
polyethylene glycol lauryl ether, and the like various photographic 
additives. 
In the present invention, the compound of the present invention may, if 
necessary, be used in combination with other hardeners. 
As supports for light-sensitive silver halide photographic materials to 
which the hardening process of the present invention is applied, there may 
be used, for example, paper, laminated paper, glass, and films and sheets 
of cellulose acetate, cellulose nitrate, polyester, polyamide, 
polystyrene, etc. These are properly selected according to the intended 
use of the photographic materials. 
When applied to gelatin films of a light-sensitive silver halide 
photographic material, the compound of the present invention displays an 
effective hardening ability without deteriorating such photographic 
properties as fog and speed of the photographic emulsion. Further, the 
compound of the present invention scarcely causes post-hardening due to 
incubation to make it possible to obtain a light-sensitive photographic 
material stabilized in quality. Even when the light-sensitive photographic 
material is stored over a long period of time, the compound of the present 
invention not only makes the photographic material more stable without any 
detrimental effect on the photographic emulsions but also shows such 
excellent hardening action as to sufficiently withstand high temperature 
quick processing and automatic processing. 
Characteristics of the hardening process of the present invention are well 
displayed particularly when techniques of high level are required, like in 
the case of color photographic materials. As mentioned previously, in 
color development adopted in the processing of color photographic 
materials, there is required a longer period of time than in the case of 
black-and-white development. Further, color photographic materials are 
ordinarily subjected to bleaching treatment. Thus, the total time required 
for the processing of color photographic materials is long. Moreover, for 
the processing of reversal color photographic materials, the first 
development is additionally required, and for the processing of external 
type reversal color photographic materials, the color development 
operation is repeated several times. Accordingly, color photographic 
materials suitable for high temperature processing are required to be 
strong in film hardness. According to the hardening process of the present 
invention, it is possible to prepare films capable of sufficiently 
withstanding the above-mentioned processing. Moreover, the compound of the 
present invention is well stable over a long period of time or against 
heat attack, and hence makes it possible to prepare color photographic 
materials which are free from disadvantages derived from excessive 
hardening and are stabilized in quality. 
Another characteristic of color photographic materials is that they are 
complex in composition and contain various compounds. Even when applied to 
color photographic materials containing couplers, e.g. 5-pyrazolone type 
magenta couplers, naphthol or phenol type cyan couplers, open-chain 
ketomethylene type yellow couplers, so-called 2-equivalent or 4-equivalent 
couplers thereof, or so-called masking couplers having arylazo groups in 
the active points, the hardening process of the present invention does not 
cause any uneven color development that is frequently observed when other 
hardeners are used. Further, the hardening process of the present 
invention is effectively applicable, if necessary, to color photographic 
materials containing ultraviolet absorbers, fluorescent brighteners, 
mordant layers, color developers, of such development inhibitor-yielding 
type compounds as disclosed in Japanese Patent Laying Open-to-Public No. 
77653/1974. 
The present invention is illustrated in more detail below with reference to 
examples, but the modes of practice of the present invention are not 
limited to the examples, and various modifications are possible within the 
scope of the invention.

EXAMPLE 1 
A neutral silver iodobromide emulsion for a negative containing 1.5 mole% 
of silver iodide was incorporated with gold and sulfur sensitizers, and 
subjected to second ripening. After the ripening, the emulsion was further 
incorporated with 4-hydroxy-6 -methyl-1,3,3a,7-tetrazaindene as a 
stabilizer, diethylene glycol as a wetting agent, and saponin as a coating 
aid. Thereafter, the emulsion was divided into 6 portions. One of the 
portions was coated onto a polyester (polyethylene terephthalate) film 
base and then dried to prepare a control sample. The remaining 5 portions 
of the emulsion were incorporated individually with a methanol or dimethyl 
sulfoxide-methanol solution containing each of 
1,2-bis(vinylsulfonyl)ethane and the exemplified compounds (2), (4), (13) 
and (17). The amount of each compound was 10.sup.-4 mole per gram of 
gelatin contained in the emulsion. The portions thus treated were 
individually coated onto a polyester film base and then dried to prepare 
samples. 
The control samples and 5 kinds of samples were measured for their 
respective hardening characteristics according to the below-mentioned 
procedure. That is, each of these samples after coating and drying was 
stored for 1 day at 25.degree. C. and 55% RH, stored for 30 days under the 
same conditions as above, and subjected to heat treatment at 50.degree. C. 
and 80% RH for 3 days. Each of the samples thus treated was dipped in a 
1.5% aqueous sodium hydroxide solution kept at 50.degree. C. to measure 
the time before the gelatin film began to dissolve. Separately, each of 
the samples, which had been stored and heat-treated under the same 
conditions as above, was dipped for 2 minutes in a 3% aqueous sodium 
carbonate monohydrate solution at 25.degree. C. Immediately thereafter, 
the surface of the gelatin film was wiped off, and then scratched with a 
sapphire needle havine a tip of 1 mm. in radius to measure a load applied 
to the needle at the time when scratches began to form on the film 
surface. The value of the load thus measured was taken as a film surface 
strength of each sample. 
Further, the samples after coating and drying were individually stored at 
25.degree. C. and 55% RH for 1 day, and then subjected to sensitometry to 
measure the speed and fog of each sample. 
The results obtained in the above measurements were as shown in Table 1, in 
which the speed of each sample was represented by a relative value when 
that of the control sample was taken as 100. 
Table 1 
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Hardening characteristics 
Time required for 
initiation of Film surface strength 
dissolution (min.) (g) 
Stored 
Stored 
Heat-treated 
Stored 
Stored 
Heat-treated 
Photographic 
for for for for for for properties 
Compound 
1 day 30 days 
3 days 1 day 
30 days 
3 days Speed 
Fog 
__________________________________________________________________________ 
Control sample 
0.5 1.0 1.0 4 7 15 100 0.15 
1,2-Bis(vinyl- 
sulfonyl)ethane 
2 3.5 5 120 190 280 93 0.13 
Exemplified more than 
compound (2) 
16 18 20 200 235 310 88 0.12 
Exemplified 
compound (4) 
11 15 20 205 290 350 90 0.12 
Exemplified more than 
more than 
compound (13) 
15 20 20 180 220 250 93 0.13 
Exemplified 
more than 
more than 
more than 
compound (17) 
20 20 20 145 160 200 96 0.14 
__________________________________________________________________________ 
As is clear from Table 1, the compounds of the present invention are more 
excellent in resistance to alkali solutions than such a conventional 
hardener as 1,2-bis(vinylsulfonyl)ethane, are less in post-hardening due 
to storage under ambient conditions and to heat treatment, and display 
markedly excellent hardening activity without deteriorating the 
photographic properties. Example 2 
A film assembly having the below-mentioned layers on a cellulose acetate 
film base was prepared and was used as a control sample containing no 
hardener. 
First layer -- Anti-halation layer 
Second layer -- Red-sensitive silver halide emulsion layer containing a 
cyan coupler 
Third layer -- Gelatin inter layer 
Fourth layer -- Green-sensitive silver halide gelatin emulsion layer 
containing a magenta coupler and the development inhibitor-yielding type 
compound disclosed in Japanese Patent Laying Open-to-Public No. 77635/1974 
Fifth layer -- Filter layer containing yellow colloidal silver 
Sixth layer -- Blue-sensitive silver halide gelatin emulsion layer 
containing a yellow coupler 
Seventh layer -- Gelatin protective layer 
Separately, samples were prepared in such a manner that each of 
bis(vinylsulfonylmethyl)ether as a control compound and the exemplified 
compounds (5) and (12) of the present invention was incorporated into each 
of the above-mentioned layers in a proportion of 0.5 .times. 10.sup.-4 
mole per gram of gelatin contained in each layer. 
The hardening characteristics of each sample were measured in the same 
manner as in Example 1. Further, the photographic properties of each 
sample were measured in such a manner that the sample was exposed through 
a wedge to white light, color developed at 38.degree. C. for 3 minutes by 
use of a color developer containing 4-amino-3-methyl-N-ethyl 
hydroxyethylaniline sulfate as a developing agent, and subjected to 
ordinary bleaching, fixing and water-washing, and then to sensitometry. 
The results obtained were as set forth in Table 2, in which the speed of 
each sample was represented by a relative value when that of the control 
sample was taken as 100, and B, G and R show that sensitometry was 
effected by measuring the color density of each sample through blue, green 
and red filters, respectively. 
Table 2 
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Hardening characteristics 
Time required for 
initiation of Film surface strength 
dissolution (min.) (g) 
Stored 
Stored 
Heat-treated 
Stored 
Stored 
Heat-treated 
Photographic properties 
for for for for for for Speed Fog 
Compound 
1 day 30 days 
3 days 1 day 30 days 
3 days B G R B G R 
__________________________________________________________________________ 
Control 
sample 1 2 5 10 16 25 100 
100 
100 
0.10 
0.10 
0.15 
Bis(vinyl- more than 
sulfonyl- 
10 18 20 200 310 380 92 90 85 0.08 
0.08 
0.12 
methyl)ether 
Exemplified 
more than 
more than 
more than 
compound (5) 
20 20 20 330 400 410 96 93 90 0.08 
0.08 
0.12 
Exemplified more than 
more than 
compound (12) 
15 20 20 300 320 350 93 89 87 0.07 
0.07 
0.12 
__________________________________________________________________________ 
From Table 2, it is understood that when applied to color photographic 
films, the compounds of the present invention display excellent hardening 
action without deteriorating the photographic properties. 
Further, each of the above-mentioned samples was subjected also to reversal 
color processing (first development, water-washing, reversal exposure, 
second development, water-washing, bleaching, water-washing, fixing and 
water-washing). As the result, the control sample showed the formation of 
marked scratches on the film surface, whereas each of the samples 
according to the present invention maintained excellent film properties 
and were not particularly deteriorated in photographic properties. 
EXAMPLE 3 
A silver chlorobromide emulsion containing 30% of silver bromide was 
incorporated with gold and sulfur sensitizers, and subjected to a second 
ripening. After the ripening, the emulsion was further incorporated with a 
stabilizer, a coating aid and a magenta coupler, and then divided into 4 
portions. One of the portions was coated onto a polyethylene laminated 
paper and then dried to prepare a control sample containing no hardener. 
The remaining 3 portions of the emulsion were incorporated individually 
with an acetone-methanol solution containing each of the exemplified 
compound (5) and such control compounds as 1,2-bis(vinylsulfonyl)ethane 
and 1,3,5-tris(vinylsulfonyl)benzene. The amount of each compound was 
10.sup.-4 mole per gram of gelatin contained in the emulsion. The portions 
thus treated were individually coated onto a polyethylene laminated paper 
and then dried to prepare 3 kinds of samples containing hardeners. 
Each of the thus prepared samples were measured in their respective 
hardening characteristics in the same manner as in Example 1, and was 
color developed at 30.degree. C. for 3 minutes and 30 seconds with a color 
developer containing 
3-methyl-N-ethyl-.beta.-methanesulfonamidoethyl-4-aminoaniline sulfate as 
a developing agent, and was subjected to bleach-fixing and water-washing, 
and then to sensitometry. The results obtained were as set forth in Table 
3, in which the speed was represented by a relative value when that of the 
control sample was taken as 100. The sensitometry was carried out by 
measuring the reflection density through a green filter. 
Table 3 
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Hardening characteristics 
Time required for 
initiation of Film surface strength 
dissolution (min.) 
(g) 
Stored 
Stored 
Heat-treated 
Stored 
Stored 
Heat-treated 
Photographic 
for for for for for for properties 
Compound 1 day 
30 days 
3 days 1 day 
30 days 
3 days Speed 
Fog 
__________________________________________________________________________ 
Control sample 
0.5 0.5 3 5 5 12 100 0.05 
Exemplified more than 
compound (5) 
15 20 20 70 110 130 97 0.04 
1,2-Bis(vinyl- 
sulfonyl)ethane 
4 7 8 45 130 150 97 0.04 
1,3,5-Tris(vinyl- 
more than 
more than 
sulfonyl)benzene 
13 20 20 60 80 120 95 0.04 
__________________________________________________________________________ 
From Table 3, it is understood that the compound of the present invention 
displays markedly excellent hardening action without deteriorating the 
photographic properties, and is less in post-hardening due to storage 
under ambient conditions and to heat treatment than in the case of the 
known similar compounds.