Process for preparing impregnated polymer latex compositions

In the process for preparing impregnated polymer latex compositions by impregnating a hydrophobic substance in dispersed polymer particles in an aqueous polymer latex, the improvement comprises impregnating said hydrophobic substance, wherein the impregnation is effected by mixing said hydrophobic substance which is solid state, a water-miscible organic solvent and aqueous polymer latex wherein a polymer of the polymer latex is prepared from ethene monomers and containing at least one hydrophilic group.

The invention relates to a process for immersing a hydrophobic substance in 
dispersed polymer particles within an aqueous polymer latex. More 
particularly, it relates to a process for preparing polymer latex 
compositions in which a hydrophobic photographic additive is impregnated. 
In the preparation of light-sensitive silver halide photographic materials, 
there have been employed several methods to disperse uniformly various 
hydrophobic compounds, particularly dye-forming agents or UV absorbents in 
a hydrophilic colloidal solution such as gelatin. 
One of the methods comprises mixing a solid or liquid hydrophobic compound 
(I) with a hydrophobic colloidal solution (II), dispersing (I) 
mechanically within (II) by passing the resulting mixture through a high 
energy mill such as a colloid mill several times to make a dispersion, and 
finally dispersing the dispersion in a hydrophilic colloidal solution. 
However, the method involves several defects that an insufficient 
dispersion is apt to take place and the resulting dispersion is often 
unstable. Further, in this method, a large quantity of energy is required 
to attain the fine pulverization of (I) to the desired extent and the 
sufficient dispersion. 
The consumption of such a large quantity of energy often accompanies an 
accumulation of heat or an undesirable partial heating which causes 
chemical changes of ingredients involved. 
Another method of dispersing a hydrophobic compound in a hydrophilic 
colloidal solution is disclosed in U.S. Pat. Nos. 2,304,940 and 2,322,027 
in which a hydrophobic compound is first dissolved in an oil or a solvent 
having a high boiling point to make a solution, and then, the resulting 
oily solution is dispersed in a hydrophilic colloidal solution. A 
modification of the method is disclosed e.g. in U.S. Pat. No. 2,801,171 in 
which an auxiliary solvent having a low molecular weight such as ethyl 
acetate or a lower ketone may optionally be used for accelerating the 
solubilization of the hydrophobic compound into the oily solvent. 
In the preparation of silver halide color photographic emulsion comprising 
a ballasted dye-forming agent (hereinafter referred to as "coupler"), 
there has been extensively employed a method in which a ballasted coupler 
is dissolved in an oily solvent having a high boiling point called 
"coupler solvent" and the resulting solution is dispersed in a hydrophilic 
colloidal solution such as silver halide gelatin emulsion. 
Even by this method, a finely pulverizing process with a high energy is 
required to attain the dispersion and the grain size to the desired 
extent, by which process undesirable degradation of some ingredients in 
the finely pulverized composition, such as thermal degradation, takes 
place. 
In addition, the finely pulverizing process requires a long time and a high 
cost. 
It has, therefore, been desired to improve methods of dispersing a 
hydrophobic compound such as a ballasted coupler uniformly in a 
photographic emulsion or other hydrophilic colloidal solutions. 
For this purpose, it must be avoided to employ a high energy mill which has 
been used for the dispersion of a hydrophobic substance in a hydrophilic 
colloidal solution. 
In the meantime, Japanese Patent Publication Specification No. 48-30494 
discloses a method of using a water-miscible and organic solvent-miscible 
polymer for the dispersion of a hydrophobic coupler, in order to improve 
the photographic characteristics such as image preservability. Here again, 
it is essential to employ a high energy mill for the emulsification of the 
polymer containing the coupler. 
Japanese Patent Publication Specification Nos. 51-59942 and 51-59943, as 
laid open to public inspection, disclose a method which may give 
photographic emulsions various advantages without employing a high energy 
mill which causes various disadvantages mentioned above. Here is used a 
polymer latex in which a hydrophobic substance is impregnated in dispersed 
polymer particles; and the hydrophobic substance is dispersed in a 
hydrophilic colloidal solution, while keeping the hydrophobic substance 
impregnated in the dispersed polymer particles. By using a polymer latex, 
the method can provide the thus obtained silver halide photographic 
emulsion with several desirable characteristics. Namely, the grain size of 
the dispersion containing a coupler is smaller than those obtained by 
other known methods, by which the definition of image to be obtained and 
the reactivity of the coupler with a developer may be improved. 
Further, hydrophobic compounds which could not have been used due to the 
susceptibility of oxidation may be introduced into a hydrophilic colloidal 
solution according to the method, imparting a remarkable oxidation 
resistance to the hydrophobic compounds. 
Furthermore, hydrophobic substances which are so reactive as to react with 
other ingredient in a layer may be used, suppressing the reactivity, by 
employing a polymer latex. 
Although the use of a polymer latex as the dispersed support of hydrophobic 
photographic additives has attained the improvement of photographic 
characteristics without employing a high energy mill, there still remain 
several problems to be solved. 
First, according to the above-mentioned invention, the quantity of 
hydrophobic substance which can be immersed in the dispersed particles of 
the polymer latex is insufficient. Namely, when a coupler which is a 
typical hydrophobic photographic additive is impregnated in dispersed 
particles of the polymer latex, more than equal, and in some instances 
more than twice amounts by weight of the dispersed particles based on the 
coupler are required, and hence, light-sensitive materials prepared 
therefrom become thick in size and the developing properties as well as 
resolution thereof become worse. Secondly, according to the above method, 
the dispersion concentration of the polymer latex is relatively low, and 
hence, the polymer latex has to be used in large quantities by which the 
dry load is increased. Thirdly, a water-miscible organic solvent is used 
in relatively large quantities when the hydrophobic substance is 
impregnated in the dispersed particles because the hydrophobic substance 
has been solved in a water-miscible organic solvent before the 
impregnation and hence a large scale equipment and a long time are 
required for the removal of the solvent. 
In addition, the above-mentioned invention involves defects that usable 
polymer latices are considerably restricted in species and the stability 
of the polymer latex compositions obtained are not sufficiently stable. 
As mentioned above, the known methods failed to give satisfactory results 
and various problems still remain unsolved. 
It is, therefore, an object of the invention to provide a process for 
preparing polymer latex compositions in which a hydrophobic substance is 
impregnated, without accompanying the above-mentioned defects and without 
using a high energy. It is another object of the invention to provide a 
process for preparing polymer latex compositions in which a large quantity 
of a hydrophobic substance is impregnated in the dispersed particles. It 
is still another object of the invention to provide a process for 
preparing polymer latex compositions in which a polymer latex containing 
dispersed particles in high concentration is used. 
It is yet another object of the invention to provide a process for 
preparing polymer latex compositions which allows a ready impregnation of 
a hydrophobic substance in the dispersed particles and a ready removal of 
solvents after the impregnation. 
It is a further object of the invention to provide a process for preparing 
polymer latex compositions which does not remarkably restrict the species 
of polymer latex to be employed. 
The inventors have found, after investigations to achieve the 
above-mentioned objects, that the above-mentioned problems may be solved 
by impregnating a hydrophobic substance in dispersed polymer particles, by 
mixing a hydrophobic substance which is solid state, a water-miscible 
organic solvent and aqueous polymer latex. The solid state hydrophobic 
substance is gradually dissolved by the water-miscible solvent, while said 
dissolved hydrophobic substance is being impregnated into the dispersed 
polymer particles. In accordance with the process for preparing 
impregnated polymer compositions of the invention, the following superior 
effects may be obtained: 
(1) The compositions are not degraded by the action of generating heat 
because no dispersing equipment with a high energy is required. 
(2) Light-sensitive materials having a thin thickness may be prepared 
because a hydrophobic substance may be impregnated in large quantities in 
dispersed polymer particles. Thus, the developing properties and the 
resolution are improved at the same time. 
(3) The dry load may be decreased because an aqueous polymer latex 
containing dispersant in high concentration may be used. 
(4) Removal of solvent used may be performed over relatively short period 
and no large scale equipment for removing the solvent is required because 
an organic solvent is used in a small quantity upon impregnation. 
(5) There is no remarkable limitation as to the species of aqueous polymer 
latex to be used. There may be used hydrophobic substances which may not 
have been used for impregnation and the resulting impregnated compositions 
are quite stable. 
In the process of the invention, the following four methods of mixing an 
aqueous polymer latex, a hydrophobic substance and a water-miscible 
organic solvent are considered upon impregnating the hydrophobic substance 
in the dispersed polymer particles. 
The first method comprises making a suspension of a hydrophobic substance 
in an aqueous polymer latex and then adding a water-miscible organic 
solvent to the suspension in small portions. 
The second method comprises adding and mixing a hydrophobic substance and a 
water-miscible organic solvent from different hoppers to an aqueous 
polymer latex at the same time. 
The third method comprises adding and mixing an aqueous polymer latex, a 
hydrophobic substance and a water-miscible organic solvent in one 
receptacle at the same time. 
The fourth method comprises adding and mixing a hydrophobic substance to a 
mixture of an aqueous polymer latex and a water-miscible organic solvent. 
Although the objects of the invention may be attained by any of the 
above-mentioned four methods, the first and fourth methods are preferable 
from the viewpoint of ready operation. 
As the water-miscible organic solvent employed in the invention, those 
which are miscible with water at any proportion are most preferable. 
However, solvents which are miscible with water more than 10% by weight 
may be used in the invention. 
As the solvents must be removed at a later stage, it is preferable that 
they boil at below 150.degree. C., preferably below 100.degree. C. The 
solvents may be used alone or admixed. 
Further, the solvents may be used in admixture with a solvent havng a high 
boiling point such as dibutyl phthalate, tricresyl phosphate, triphenyl 
phosphate or diethyl laurylamide. 
The solvents may also be used in admixture with a water-miscible solvent. 
Examples of such water-miscible solvents are acetone, methyl ethyl ketone, 
methanol, ethanol, isopropanol, tetrahydrofuran, N-methylpyrrolidone, 
dimethylformamide and dimethylsulfoxide. 
The mixing ratio of organic solvents to water will be 0.1-10:1, preferably 
0.7-3:1 by weight in the polymer latex dispersion. 
The hydrophobic substance of the invention includes those which are soluble 
in water up to about 10%, preferably up to 5%, more preferably up to 2%, 
and most preferably up to 1%. Examples of the hydrophobic substances are 
agricultural chemicals, pharmaceuticals, dyes and, of course, photographic 
additives. 
Representative hydrophobic photographic additives which may be impregnated 
by the process of the invention are couplers, UV absorbents, development 
inhibitor-releasing substances, cross-oxidation dye-releasing agents and 
photographic dyes. Also, fluorescent brightening agents, antihalation 
agents or antiirradiation agents and developing agents may be impregnated. 
More concretely, open chain methylene series yellow couplers, 5-pyrazolone 
series magenta couplers, phenol- or naphthol series cyan couplers, which 
may be either so-called two equivalents type or so-called four equivalents 
type, are mentioned as the hydrophobic couplers. The hydrophobic couplers 
may be used in combination with azo type colored couplers, osazone type 
compounds or diffusible dye-releasing couplers for automasking. Further, 
so-called compating couplers, DIR couplers (development 
inhibitor-releasing couplers) or BAR couplers (bleach 
accelerator-releasing couplers) may be used admixed in order to improve 
photographic characteristics. 
There have been used open chain ketomethylene compounds as the yellow 
couplers. They are, for example, pivalylacetanilide type yellow couplers 
disclosed in U.S. Pat. No. 3,265,506; benzoyl-acetanilide type yellow 
couplers disclosed in British patent specification No. 1,240,600 and U.S. 
Pat. No. 2,875,051; active point-o-aryl substituted type compounds which 
are commonly referred to as two equivalents type couplers disclosed in 
U.S. Pat. No. 3,408,194; active point-o-amyl substituted type compounds 
disclosed in U.S. Pat. No. 3,447,928; active point-hydantoin substituted 
type compounds disclosed in British patent specification No. 1,351,424; 
active point-urazol substituted compounds and active point-succinimide 
substituted compounds disclosed in British patent specification No. 
1,331,179; active point-mono-oxoimide substituted compounds and active 
point-fluorine substituted compounds disclosed in British patent 
specification No. 94,490; active point-chlorine or bromine substituted 
compounds disclosed in British patent specification No. 780,507; and 
active point-o-sulfonyl substituted compounds disclosed in British patent 
specification No. 1,092,506, and the like. 
As the magenta couplers used in the invention are mentioned pyrazolone 
series, pyrazolotriazole series, pyrazolino-benzimidazole series and 
indazolone series compounds. They are, for example, pyrazolone series 
magenta couplers disclosed in U.S. Pat. Nos. 3,127,269; 2,600,788; 
3,519,429; 3,419,391; 3,062,653 and 3,684,514 and British patent 
specification Nos. 1,342,553 and 1,399,306; pyrazolotriazole series 
magenta couplers disclosed in British patent specification No. 1,247,493; 
pyrazolinobenzimidazole series magenta couplers disclosed in U.S. Pat. No. 
3,061,432 and indazolone series magenta couplers disclosed in British 
patent specification No. 1,335,603. Thereof, especially suitable for the 
process of the invention are those disclosed in U.S. Pat. Nos. 3,684,514 
and 3,127,269. 
As the cyan couplers used in the invention are mentioned, for example, 
phenol compounds disclosed in U.S. Pat. Nos. 2,423,730, 2,801,171 and 
2,895,826; active point-o-aryl substituted naphthol compounds disclosed in 
U.S. Pat. No. 2,474,293 and British patent specification No. 1,084,480; 
phenol and naphthol compounds disclosed in Canadian Patent Specification 
No. 913,082 and U.S. Pat. No. 3,737,316. 
As the colored magenta couplers, are employed compounds in which active 
points of a colorless magenta couplers are substituted with arylazo or 
heterocyclic aryl azo groups, for example, compounds disclosed in U.S. 
Pat. Nos. 3,005,712; 2,983,608; 2,801,171 and 3,684,514; and British 
patent specification No. 937,621. 
As the colored cyan couplers, are employed active point-arylazo substituted 
compounds disclosed in U.S. Pat. Nos. 3,034,892; 2,521,908 and 3,811,892 
and British patent specification No. 1,255,111. Masking couplers that 
react with oxidized developer to form dyes flowing into the processing 
solution disclosed in British patent specification No. 1,084,480 may also 
be employed. 
As the competing couplers, are employed, for example, citrazinic acid or 
the like disclosed in U.S. Pat. No. 2,742,832. As Weiss couplers, are 
employed those disclosed in U.S. Pat. No. 2,998,314. 
Further, so-called DIR substance (development inhibitor-releasing 
substance) disclosed in U.S. Pat. Nos. 3,632,345, 3,928,041; 3,958,993 and 
3,961,959 are preferably employed. 
As the UV absorbents, are employed triazoles, triazines and benzophenones 
or the like disclosed in U.S. Pat. Nos. 3,004,896; 3,253,921; 3,533,794; 
3,292,525; 3,705,805; 3,738,837 and 3,754,919; British patent 
specification No. 1,321,355 and Japanese Patent Publication No. 50-25237, 
as laid open to public inspection, or the like. 
Further, acrylonitrile series compounds disclosed in U.S. Pat. Nos. 
3,052,636 and 3,707,535 may also be employed. It is preferable that a 
series of U.V. absorbents sold by Ciba-Geigy AG, Switzerland, under the 
trade names Tinuvin PS, Tinuvin 320, Tinuvin 326, Tinuvin 327 or Tinuvin 
328 are used, alone or admixed, as the UV absorbent. 
Furthermore, azoles disclosed in U.S. Pat. Nos. 2,537,877; 2,739,971; 
2,739,888; 2,784,087 and 3,250,687 and high molecular triazine compounds 
disclosed in U.S. Pat. Nos. 3,512,984 and 3,549,374 may also be used. 
As other hydrophobic photographic additives which may be readily 
impregnated according to the process of the invention are mentioned, for 
example, photographic dyes, disclosed in U.S. Pat. Nos. 2,751,298 and 
3,506,443, DDR couplers (diffusible dye-releasing couplers) disclosed in 
U.S. Pat. Nos. 3,443,939; 3,443,940; 3,443,941 and 3,725,062; indicator 
dyes disclosed in U.S. Pat. No. 3,647,437; sulfonamide series reducing 
agents disclosed in U.S. Pat. No. 3,810,321; reductone series reducing 
agents disclosed in U.S. Pat. Nos. 3,672,896 and 3,679,426; bisnaphthol 
series reducing agents disclosed in U.S. Pat. Nos. 3,672,904 and 
3,751,249; hydrophobic developers disclosed in U.S. Pat. Nos. 3,672,896; 
3,672,904; 3,679,426 and 3,751,249; and DRR substances (dye-releasing 
redox material) which are so-called cross oxidation dye-releasing agents 
disclosed in U.S. Pat. Nos. 3,628,952; 3,698,897 and 3,725,062 and Belgian 
patent specification Nos. 788,268; 796,040; 796,041 and 796,042. Further, 
the process of the invention may be applied to photographic materials 
described in Product Licensing Index vol. 92, 110 (1971). 
The hydrophobic substance may be dispersed in a dispersion medium of 
polymer latex in an amount of 1/100 to 1 part, preferably 1/50 to 1/2 part 
by weight, based on 1 part of the dispersion medium. 
It is presumed that the solubility of the hydrophobic substance in the 
medium is rather low, in the abovementioned mixing proportion. To wit, it 
is presumed that solubility of the hydrophobic substance in the dispersion 
medium would be below 1%. It is remarkable, however, that the hydrophobic 
substance may be readily and relatively rapidly dispersed in the medium 
containing polymer particles, in spite of the low solubility. 
The aqueous polymer latex of the invention containing dispersed polymer 
particles are required that the polymer particles are finely dispersed in 
a medium comprising finally water and a water-miscible solvent. 
The mean grain size of dispersed polymer particles which may be applied to 
the invention is below 5.mu., preferably below 1.mu., more preferably 
below 0.5.mu.. It is preferable that the particle size distribution is 
uniform such that particles whose grain size ranges from 70% to 130% with 
respect to the mean grain size are more than 70%, in number, among the 
total particles. 
The aqueous polymer latex of the invention containing dispersed polymer 
particles is also required not to cause flocculation or precipitation by 
addition of a water-miscible organic solvent, and that the dispersed 
particles are dispersed stably. 
It is preferable that the dispersed particles of aqueous polymer latex show 
no flocculation or precipitation when they are mixed with a hydrophilic 
colloidal solution, such as gelatin, and that the resulting liquid forms a 
transparent film after coating and drying on a support. 
Such aqueous polymer latex may be prepared e.g. by emulsion 
copolymerization of ethene monomers having radical-polymerizing capacity. 
The polymers contain at least one species of compound having hydrophilic 
group such as sulfo group, sulfonate group, sulfonyl group, carboxy group, 
carboxylate group, hydroxy group, amide group, sulfonamide group, 
quaternary ammonium group, polyalkylene oxide group or sulfate group. 
The amount of compound having hydrophilic group within the polymer may 
usually be below 50%, but monomers having hydroxy group as the hydrophilic 
group may be contained up to 70%. 
According to the invention, aqueous polymer latices containing dispersed 
particles in high concentration up to 60% by weight may be used. 
As mentioned above, the aqueous polymer latices used in the invention may 
be prepared by emulsion copolymerization of ethene monomers having 
radical-polymerizing capacity. Non-limiting list of monomers to be 
employed will be given below: 
(1) acrylic esters 
methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, glycidyl 
acrylate, 2-acetoacetoxyethyl acrylate, or the like; 
(2) methacrylic esters 
methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl 
methacrylate, glycidyl methacrylate, 2-acetoacetoxyethyl methacrylate, or 
the like; 
(3) acrylic amides 
butyl acrylamide, N, N-diethyl acrylamide, N, N-diisopropyl acrylamide, 
dodecylacrylamide, or the like; 
(4) methacrylic amides 
butyl methacrylamide, N,N-diethyl methacrylamide, dodecyl methacrylamide, 
N,N-diisopropyl methacrylamide, or the like; 
(5) vinyl esters 
vinyl acetate, vinyl butanoate, or the like; 
(6) vinyl halides 
vinyl chloride, or the like; 
(7) vinylidene halides 
vinylidene chloride, or the like; 
(8) vinyl ethers 
vinyl methyl ether, vinyl ethyl ether, vinyl hexyl ether, vinyl glycidyl 
ether, or the like; 
(9) styrene compounds 
styrene, .alpha.-methstyrene, hydroxystyrene, chlorostyrene, methylstyrene, 
or the like; 
(10) other compounds 
ethylene, propylene, butylene, butadiene, isoprene, acrylonitrile, or the 
like; 
(11) Compounds having hydrophilic group 
##STR1## 
(In the above formulae, R represents a hydrogen atom or a lower alkyl group 
and M represents an alkali metal atom, hydrogen atom or ammonium group.) 
The following is a non-limiting list of copolymer compositions contained in 
the aqueous polymer latex of the invention: 
##STR2## 
The aqueous polymer latices used in the invention may be synthesized by 
emulsion copolymerization which is performed under per se know conditions. 
For example, an emulsifier, polymerization initiator, polymerization 
accelerator and polymerization regulator are added, if necessary, to a 
degasified distilled water, 10-60% by weight of monomer is added thereto 
and the mixture is heated at 40.degree.-90.degree. C. with stirring for 
several hours to complete polymerization. 
As the emulsifier to be employed, are mentioned, for example, anionic 
surfactants such as sodium alkylbenzenesulfonate and sodium polyethylene 
oxide alkyl ether sulfate; nonionic surfactants such as polyethylene oxide 
alkyl ethers; amphoteric surfactants such as betaine or sulfobetaine type; 
and cationic surfactants such as quaternary ammonium salts. The surfactant 
may be used alone or in combination. 
As the polymerization initiator to be employed, are mentioned, for example, 
ammonium persulfate, potassium persulfate and hydrogen peroxide. As the 
polymerization accelerator to be employed, are mentioned, for example, 
acid sodium sulfite and acid sodium carbonate. 
As the polymerization regulator to be employed, are mentioned, for example, 
mercaptan compounds, isopropanol and tert-butanol. 
There may be employed other additives which will give the reaction good 
results, if necessary. 
The grain size of dispersed polymer particles in the aqueous polymer latex 
obtained by the method mentioned above will be influenced by various 
factors, such as species and amounts of emulsifier, monomer and 
polymerization initiator and preparation conditions (e.g. temperature, 
reaction period and agitation speed), but it is preferably adjusted to 
about 0.01-1.mu.. 
The concentration of polymer in the aqueous polymer latex to be used in the 
invention will be preferably 5-60%, more preferably 5-30% by weight. 
Preparations of representative aqueous polymer latices to be employed in 
the invention will be given below: 
PREATION 1 
Aqueous Dispersion Comprising Illustrated Copolymer No. 1 
Necks of a four-necked flask (2 liter) were equipped with a thermometer, 
cooler, dropping funnel (A) (300 ml) and dropping funnel (B) (300 ml), 
respectively, and further with a stirrer. To the flask were added 2 g of 
sodium dodecylbenzene-sulfonate (Newlex R, trade name, Nissan Chem. Co.,) 
and 600 g of distilled water, and nitrogen gas was introduced for 30 
minutes. The mixture was heated to 80.degree. C. and 0.5 g of ammonium 
persulfate and 0.2 g of acid sodium sulfite were added. Immediately after 
that, 161.7 g of ethyl acrylate and 38.7 g of sodium 
3-acryloyloxypropane-1-sulfonate (200 ml of acqueous solution) were 
simultaneously added dropwise from the dropping funnels (A) and (B), 
respectively, over 30 minutes. After completion of addition, the mixture 
was stirred for 1 hour and cooled to ambient temperature to complete the 
reaction. The polymer concentration in thus obtained aqueous dispersion 
was 20% by weight and the grain size of polymer particles was 
approximately 0.07.mu.. The molecular weight of the polymer was 120,000. 
PREATION 2 
Aqueous Dispersion Comprising Illustrated Copolymer No. 6 
Necks of a four-necked flask (1 liter) were equipped with a thermometer, 
cooler, dropping funnel (A) (300 ml) and dropping funnel (B) (300 ml), 
respectively, and further with a stirrer. To the flask were added 2 g of 
sodium lauryl sulfate (Syntlex L-100, trade name, Nippon Yushi Co.,) and 
266 g of distilled water, and nitrogen gas was introduced for 30 minutes. 
The mixture was heated to 80.degree. C. and 0.5 g of azobiscyanovaleric 
acid was added. Immediately after that, a mixture of 169.1 g of n-butyl 
acrylate and 8.8 g of 2-acetoacetoxyethyl acrylate, and 22.1 g of sodium 
1-sulfopropyl-3-acrylamide (200 ml of aqueous solution) were 
simultaneously added dropwise from the dropping funnels (A) and (B), 
respectively, over 30 minutes. After completion of addition, the mixture 
was stirred for 1 hour and cooled to ambient temperature to complete the 
reaction. The polymer concentration of thus obtained aqueous dispersion 
was 30% by weight and the grain size of polymer particles was 
approximately 0.09.mu.. The molecular weight of the polymer was 68,000. 
PREATION 3 
Aqueous Dispersion Comprising Illustrated Copolymer 14 
Necks of four-necked flask (2 liter) were equipped with a thermometer, 
cooler, dropping funnel (300 ml) and stirrer, respectively. To the flask 
were added 10 g of sodium laurylsulfate (Syntlex L-100, trade name, Nippon 
Yushi Co.,) and 600 g of distilled water. Nitrogen gas was introduced for 
30 minutes and the mixture was heated to 85.degree. C. 0.5 g of potassium 
persulfate, 0.2 g of acid sodium sulfite and 0.5 g of p-toluenesulfonic 
acid were added, and immediately after that a mixture of 160 g of isobutyl 
acrylate and 40 g of glycidyl acrylate was added dropwise from the 
dropping funnel over 30 minutes. After completion of addition, the mixture 
was stirred for 15 hours and cooled to ambient temperature to complete the 
reaction. The polymer concentration of thus obtained aqueous dispersion 
was 20% by weight and the grain size of polymer particles was 
approximately 0.1.mu.. The results of NMR spectrometry and elementary 
analysis confirmed the polymer composition to be illustrated compound No. 
14. The molecular weight of the polymer was 140,000. 
PREATION 4 
Aqueous dispersion comprising illustrated copolymer 15 
Necks of four-necked flask (2 liter) were equipped with a thermometer, 
cooler, dropping funnel (A) (300 ml) and dropping funnel (B) (200 ml), 
respectively, and further with a stirrer. To the flask were added 2 g of 
sodium triisopropylnaphthalenesulfonate and 200 g of distilled water. 
Nitrogen gas was introduced for 30 minutes and the mixture was heated to 
75.degree. C. 0.5 g of ammonium persulfate and 0.1 g of acid sodium 
sulfite were added, and immediately after that, 173.5 g of methyl 
acrylate, and 100 ml of aqueous solution comprising 26.5 g of sodium 
3-acryloyloxyphenyl-1-sulfonate and 0.2 g of sodium sulfite were 
simultaneously added dropwise from the dropping funnels (A) and (B), 
respectively, over 30 minutes. After completion of addition, the mixture 
was stirred for 1 hour and cooled to ambient temperature to complete the 
reaction. The polymer concentration of thus obtained aqueous disperison 
was 40% by weight and the grain size of polymer particles was 
approximately 0.08.mu.. The molecular weight of the polymer was 84,000. 
PREATION 5 
Aqueous dispersion comprising illustrated copolymer No. 20 
Necks of four-necked flask (2 liter) were equipped with a thermometer, 
cooler, dropping funnel (A) (300 ml) and dropping funnel (B) (300 ml), 
respectively, and further with a stirrer. To the flask were added 1 g of 
sodium dodecylbenzenesulfonate (Newlex R, trade name, Nissan Chem. Co.,) 
and 271 g of distilled water. Nitrogen gas was introduced for 30 minutes 
and the mixture was heated to 80.degree. C. Immediately after 0.5 g of 
azobiscyanovaleric acid was added, 159 g of ethyl acrylate and 41 g of 
sodium 3-acryloyloxypropane-2-hydroxy-1-sulfonate (100 ml of aqueous 
solution) were simultaneously added dropwise from the dropping funnels (A) 
and (B), respectively, over 30 minutes. After completion of addition, the 
mixture was stirred for 1 hour and cooled to ambient temperature to 
complete the reaction. The polymer concentration of thus obtained aqueous 
dispersion was 35% by weight and the grain size of polymer particles was 
approximately 0.09.mu.. The molecular weight of the polymer was 117,000. 
Following the procedures in the Preparations, aqueous polymer latices 
comprising previously illustrated copolymers may readily be prepared. 
Polymer latex compositions in which hydrophobic photographic additives were 
impregnated according to the process of the invention may be applied to 
any object to which polymer latex compositions obtained by known methods 
may be applied. 
In accordance with the process of the invention, the previously mentioned 
objects of the invention may be achieved. Moreover, the grain size of 
polymer latex in which hydrophobic substance is impregnated, prepared by 
the process of the invention, is quite uniform. 
Accordingly, if the process is applied to couplers, the resulting 
photographic materials may present better color behavior upon color 
development, and further, developed color images show better color purity 
and fastness than those obtained by known methods. 
Further, as a result of widening the species of polymers to be chosen, the 
scope of substances for which impregnation is applied has been expanded by 
the process of the invention. 
It is quite astonishing that the process of the invention may provide 
above-mentioned remarkable results as compared with known processes, i. a. 
the closest known process in which an aqueous polymer latex is added to a 
solution of a hydrophobic substance in a water-miscible organic solvent. 
From physicochemical observation of the process in which a hydrophobic 
substance is dispersed into latex particles, it may be said that the 
dispersion according to the known process may be performed under severe 
conditions which, in consequence, restrict the scope of water-miscible 
solvents, latices, hydrophobic substances and various conditions to be 
chosen.

The invention is further illustrated by working examples which by no means 
restrict the scope of the invention. 
EXAMPLE 1 
To 100 ml of aqueous polymer latex (polymer concentration: 10% by weight) 
comprising illustrated copolymer No. 1 prepared according to Preparation 1 
were added, in one portion, 5 g of yellow dye-forming coupler, or 
.alpha.-(3-benzyl-2,4-dioxoimidazolidin-3-yl)-.alpha.-pivaloyl-5-[.alpha.' 
-(2,4-di-tert-amylphenoxy)butylamido]-2-chloroacetanilide in the form of 
crystals to suspend the coupler in the aqueous polymer latex. 
The suspended coupler was rapidly dissolved and impregnated in dispersed 
polymer particles by adding 100 ml of acetone in small portions. The 
acetone was distilled out with a rotary evaporator under reduced pressure 
to give a dispersion (sample 1). 
For comparison, 5 g of the above-mentioned yellow dye-forming coupler were 
dissolved in 100 ml of acetone, and 100 ml of aqueous polymer latex were 
added dropwise to the solution, with stirring, over 1 minute. 
After completion of addition, the mixture was stirred for additional 1 
minute. At that time, the coupler was dissolved and impregnated on 
dispersed polymer particles completely. The acetone was distilled out with 
a rotary evaporator to give a dispersion (comparison 1). 
The transmittance at 530 nm (green light) for the representative figure of 
grain size of polymer dispersion, stability and time required for 
impregnation were measured with respect to both samples. The results are 
shown in Table 1. 
TABLE 1 
______________________________________ 
Sample 1 
Comparison 1 
______________________________________ 
Transmittance (530 nm) 
96.7% 92.5% 
Stability (1) good a little poor 
Time required for impregna- 
tion 1.5 min. 2.5 min. 
______________________________________ 
Remark (1): 
Polymer latex particles after impregnation of coupler were subjected to 
electron microscopic analysis and determined as follows: 
good: No significant change was observed, after mixture, with respect to 
grain size distribution and presence of precipitate. 
a little poor: A little degradation was observed with respect to grain 
size distribution and presence of precipitate. 
poor: Precipitation was observed and grain size became larger. 
Similar tests were conducted using 50 ml or 35 ml of acetone (polymer 
concentration at the time of impregnation: 6.6% and 7.5%, respectively). 
In accordance with the process of the impregnation, a satisfactory 
impregnation was achieved with only 35 ml of acetone, while in comparison, 
precipitate was observed by visual observation with 50 ml or 35 ml of 
acetone. 
Sample 1 and Comparison 1 showed no flocculation during storge and they 
were fairly compatible with a gelatin solution. After mixing with gelatin 
solution, they were coated and dried, separately, on transparent 
photographic supports, giving transparent layers, respectively. 
EXAMPLE 2 
Following substantially the same procedures as in Example 1, except that 
aqueous polymer latex containing illustrated copolymer No. 28 and that 
acetone was replaced by tetrahydrofuran, there was obtained a stable 
polymer latex composition containing the impregnated coupler. 
EXAMPLE 3 
To 20 ml of aqueous polymer latex comprising illustrated copolymer No. 1 
(polymer concentration: 25% by weight) were added 5 g of cyan dye-forming 
coupler, or 
2-[.alpha.-(2,4-di-tert-amylphenoxy)-butyramido]-4,6-dichloro-5-methylphen 
ol as such and stirred to give a suspension. 
To the suspension were added 15 ml of tetrahydrofuran (hereinafter referred 
to as THF) in small portions, with stirring, and after 1-2 minutes the 
coupler was impregnated in the dispersed polymer particles completely to 
give a homogeneous dispersion. After this, the coupler was impregnated 
according to the method of the invention, using aqueous polymer latices 
having different polymer concentrations. Namely, 5 g of the aforementioned 
coupler were added, with stirring, to 17 ml of aqueous polymer latex 
(polymer concentration: 30% by weight) to give a suspension. 15 ml of THF 
were added to the suspension with stirring, in small portions, and after 
1-2 minutes the coupler was impregnated in the dispersed polymer particles 
completely to give a homogeneous dispersion. 
To the dispersions were added 30 ml or 33 ml of pure water, and THF was 
distilled out under reduced pressure with a rotary evaporator. There was 
obtained stable polymer latex compositions in which the coupler was 
impregnated. 
From the results, it has turned out that coupler-impregnated stable polymer 
latex compositions may be obtained even when a concentrated aqueous 
polymer latex (polymer concentration: &gt;20% by weight) is used. 
EXAMPLE 4 
Following substantially the same procedures as in Example 2, except that a 
magenta dye-forming coupler, or 
1-(2,4,6-trichloro-phenyl)-3-(2-chloro-5-octadecylsuccinimid-aniline)-pyra 
zolin-5-one. 30 ml of a 1:1 by volume mixture of acetone and THF as 
water-miscible organic solvent, and illustrated copolymer No. 6 (polymer 
concentration: 20% by weight) as aqueous polymer latex were used, 
respectively, there were obtained similar good results. 
EXAMPLE 5 
To 100 ml of aqueous polymer latex (polymer concentration: 10% by weight) 
comprising illustrated copolymer No. 1 used in Example 1 were added, with 
stirring, 30 ml of water-miscible organic solvent mixture comprising 1:1 
acetone and THF, and simultaneously and separately, 5 g of yellow 
dye-forming coupler, or .alpha.-(3-benzyl 
2,4-dioxoimidazolidin-3-yl)-.alpha.-pivaloyl-5-[.alpha.'-(2,4-di-tert-amyl 
phenoxy)butyramido]-2-chloroacetanilide over 1 minute. The coupler was 
completely impregnated in the dispersed polymer particles and a 
homogeneous liquid was obtained by further stirring for 1 minute. The 
solvent was distilled out with a rotary evaporator under reduced pressure, 
and there was obtained a stable impregnated polymer latex composition. 
EXAMPLE 6 
100 ml of aqueous polymer latex used in Example 5, the yellow dye-forming 
coupler used in the same, and 100 ml of acetone as water-miscible solvent 
were added, simultaneously and separately, into a 500 ml volume beaker 
over 10 seconds. The coupler was completely and mixing for 1 minute. 
The acetone was distilled out with a rotary evaporator under reduced 
pressure, and there was obtained a stable impregnated polymer latex 
composition with no flocculation or precipitation. 
EXAMPLE 7 
5 g of cyan dye-forming coupler, or 
2-[.alpha.-(2,4-di-tert-amylphenoxy)butyramido]-4,6-dichloro-5-methylpheno 
l were dissolved in a mixture of 5 g of dibutyl phthalate and 15 ml of 
ethyl acetate. To the solution were added 75 ml of 3.5% gelatin solution 
containing alkylnaphthalensulfonic acid (Alkanol XC, trade name, Dupont 
Co.,) and the mixture was ultrasonic-dispersed by a usual method to give a 
dispersion A. Meanwhile, 5 g of the aforementioned cyan dye-forming 
coupler were added to 50 ml of aqueous polymer latex (polymer 
concentration: 20% by weight) comprising the illustrated copolymer No. 6 
prepared in Preparation 2, as such, and the mixture was stirred to make a 
suspension. To the suspension were added 30 ml of THF in small portions, 
and after 1-2 minutes, the coupler was dissolved and impregnated in the 
dispersed polymer particles, affording a homogeneous dispersion. 50 ml of 
pure water were added and the THF was distilled out with a rotary 
evaporator under reduced pressure to give a dispersion C. 
Subsequently, 100 ml of the same aqueous polymer latex, the polymer 
concentration of which was reduced to 10% by weight, were added dropwise 
to a solution of 5 g of the above-mentioned cyan coupler in 160 ml of THF 
over 2 minutes. The THF was removed in the similar way to give a 
dispersion B. 
The thus obtained coupler dispersions A, B and C were mixed, respectively, 
with silver chlorobromide emulsions for red-sensitive paper and coated on 
photographic paper supports coated with a polymer film as follows: 
______________________________________ 
Comparison 2 
Comparison 3 
Sample 2 
______________________________________ 
Dispersion A B C 
Coupler (mg/dm.sup.2) 
7.4 7.8 7.2 
Silver (mg/dm.sup.2) 
4.1 4.2 4.0 
Gelatin (mg/dm.sup.2) 
38.2 39.0 37.3 
______________________________________ 
The specimens were wedge-exposed and developed at 25.degree. C. for 4 
minutes, according to usual method, with a developer having the following 
composition: 
______________________________________ 
2-Methyl-4-(N--ethyl-N-- 
.beta.-methanesulfonamidoethyl- 
amino) aniline 3/2 sulfate 
4.5 g 
Sodium carbonate monohydrate 
20 g 
Potassium bromide 2.0 g 
Sodium sulfite 3.0 g 
Hydroxylamine sulfate 2.0 g 
Sodium hexametaphosphate 
2.0 g 
Benzyl alcohol 10 ml 
Water to make 1 liter 
(pH = 10.1) 
______________________________________ 
The results are shown in Table 2. 
TABLE 2 
______________________________________ 
Relative speed 
D max. .gamma. 
D min. 
______________________________________ 
Comparison 2 
100 2.55 3.20 0.05 
Comparison 3 
98 2.41 3.01 0.03 
Sample 2 100 2.52 3.10 0.03 
______________________________________ 
Here, the relative speed means a relative sensitivity when Comparison 2 is 
100. 
From the above results, it has turned out that the process of the invention 
requires not so much solvent as in known processes and gives the same 
grade of photographic characteristics. 
EXAMPLE 8 
The Comparisons 2 and 3 and Sample 2 were processed in the similar manner 
as in Example 7 and subjected to acceleration tests at 50.degree. C. and 
80% relative humidity for 2 weeks. 
The rates of remained dyes of colored dyes at D max part were compared and 
the results are shown in Table 3. 
TABLE 3 
______________________________________ 
D max 
Before After Remaining 
processing 
processing 
rate Remarks 
______________________________________ 
Comparison 2 
2.55 1.90 78.4% turned to 
green 
Comparison 3 
2.41 2.23 92.5% 
Sample 2 2.52 2.31 91.7% 
______________________________________ 
As is clear from Table 3, Sample 2 according to the invention shows better 
image preservability than that of Comparison 2 and possesses 
characteristics comparable to those of Comparison 3. 
EXAMPLE 9 
A solution of 10 g of magenta dye-forming coupler, or 
4,4'-bis{1-(2,4,6-trichlorophenyl)-3-[3-(2,4-di-tert-amylphenoxyacetamido) 
benzamido]-pyrazolin-5-one} and 1.2 g of DIR substance, or 
2-(1-phenyltetrazolyl-5-thio)-4-octadecylsuccinimido)indanone in a mixture 
of 10 g of tricresyl phosphate and 30 ml of ethyl acetate was added to 75 
ml of 3.5% gelatin solution containing Alkanol XC (trade name) as a 
dispersant, and the mixture was protect-dispersed with a colloid mill 
according to a conventional method to give a dispersion D. 
Subsequently, 10 g of the above-mentioned magneta dye-forming coupler and 
1.2 g of the DIR substance were added to 50 ml of aqueous polymer latex 
(polymer concentration: 20% by weight) comprising the illustrated 
copolymer No. 20 prepared in Preparation 5, and the mixture was stirred to 
make a suspension. 
To the suspension were added 30 ml of 1:1 by volume mixture of acetone and 
THF, and then the coupler and DIR substance were completely dissolved in 
the solvent and impregnated in dispersed polymer particles within 1-2 
minutes to give a homogeneous liquid, dispersion E. 
The dispersions D and E were mixed with green-sensitive color negative 
silver iodobromide emulsions and coated on triacetate bases, respectively, 
to make specimens as follows: 
______________________________________ 
Coupler Silver 
Dispersion 
(mg/dm.sup.2) 
(mg/dm.sup.2) 
______________________________________ 
Comparison 4 
D 9.2 12.0 
Sample 3 E 9.1 11.9 
______________________________________ 
The specimens were wedge-exposed and processed according to developing 
process for Sakura Color II. The results are shown in Table 4. 
TABLE 4 
______________________________________ 
Relative 
sensitivity 
D max .gamma. 
D min 
______________________________________ 
Comparison 4 
100 2.2 0.82 0.21 
Sample 3 97 2.0 0.79 0.16 
______________________________________ 
From the results in Table 4, it has turned out that when the process of the 
invention is applied to the dispersion of DIR substance, it shows 
characteristics comparable to those obtained by known methods. 
Here, the relative sensitivity means a sensitivity when the comparison is 
100. Besides, according to the process of the invention, better 
characteristics like granule property were obtained. 
EXAMPLE 10 
To 75 ml of aqueous polymer latex (polymer concentration: 20% by weight) 
comprising the illustrated copolymer No. 6 were added 12 g of DRR 
substance, or 
4-[3-{5-hydroxy-6-(2'-methylsulfonyl-4'-nitrophenylazo)-1-tert-butylaminos 
ulfonyl}benzenesulfonamido]-1-hydroxy-2-[.DELTA.-(2,4-di-tert-amylphenoxy)- 
n-butyl]naphthamide, and 50 ml of THF were added, with stirring. After 1-2 
minutes, the DRR substance was dissolved and impregnated in the dispersed 
polymer particles and a homogeneous liquid was obtained. The THF was 
removed with a rotary evaporator under reduced pressure to give a 
homogeneous dispersion of DRR substance. Meanwhile, a dispersion for 
comparison was prepared according to usual protect dispersion, using 
diethyllaurylamide as a high boiling point solvent. 
Subsequently, the both dispersions were first mixed with negative silver 
bromide emulsions, then added a hardener and spreader, and finally coated 
on polyester film bases as under, respectively, according to the method 
disclosed in Japanese Patent Publication 47-126331, as laid open to public 
inspection, to give photographic light-sensitive elements as follows: 
DRR substance, 1.1.times.10.sup.-5 mol/dm.sup.2 
Silver, 10 mg/dm.sup.2 
gelatin, 33 mg/dm.sup.2 
Following this, an image-receiving element was prepared by coating, on a 
polyester film base, a mortant layer consisting of 25 mg/dm.sup.2 of poly 
(styrene, 2-vinylbenzyl chloride, 
2-N-benzyl-N,N-dimethyl-N-vinylbenzyl-ammonium chloride, 2-divinylbenzene) 
in molar ratio of 4.90:0.49:4.41:0.2 and 13 mg/dm.sup.2 of gelatin. 
The above-mentioned photographic light-sensitive element was wedge-exposed 
and piled up on the image-receiving element. The thus obtained sandwitch 
structure was passed through a pair of press rollers to introduce the 
under-mentioned viscous processing solution between the sandwitch 
structure: 
______________________________________ 
Sodium hydroxide 40 g 
4-Hydroxymethyl-4-methyl-1- 
phenyl-5-pyrazolidone 4 g 
5-Methylbenzyltriazole 
0.1 g 
Potassium bromide 0.1 g 
Hydroxyethylcellulose 25 g 
Distilled water to make 1 liter 
______________________________________ 
After 90 seconds, the image-receiving element was stripped off and washed 
with water to adjust pH to 7. Good cyan printed images were obtained on 
the image-receiving elements. The results are given in Table 5. 
TABLE 5 
______________________________________ 
Relative sensitivity 
Fog D max 
______________________________________ 
Comparison 100 0.20 1.84 
Present process 
104 0.18 1.88 
______________________________________ 
Better results were obtained according to the process of the invention than 
known methods with respect to both sensitivity and D max. 
EXAMPLE 11 
To a mixture of 6 g of dibutyl phthalate and 20 ml of ethyl acetate were 
dissolved, as UV absorbents, 2.0 g of 2-benzotriazolyl-4-tert-butylphenol, 
1.5 g of 2-benzotriazolyl-4,6-di-tert-butylphenol, 2.5 g of 
2-(5-chlorobenzotriazolyl)-4,6-di-tert-butylphenol and 2.5 g of 
2-(5-chlorobenzotriazolyl)-4-methyl-6-tert-butylphenol. The resulting 
solution was protect-dispersed in a gelatin solution with a colloid mill 
according to a usual method to give a dispersion F. 
After this, the same amounts mixture of the above-mentioned UV absorbents 
were added to 30 ml of aqueous polymer latex used in Example 4 and 
suspended. To the suspension were added 20 ml of THF, with stirring, so 
that the UV absorbents were completely dissolved and impregnated in the 
dispersed polymer particles within 1-2 minutes to give a homogeneous 
liquid. The organic solvent was removed with a rotary evaporator under 
reduced pressure to give a dispersion H. Further, 8.5 g of a mixture of 
the above-mentioned UV absorbents were dissolved in 100 ml of acetone, and 
to the solution were added dropwise 60 ml of above-mentioned aqueous 
polymer latex (polymer concentration: 10% by weight) over 1 minute. After 
completion of addition, the acetone was removed with a rotary evaporator 
under reduced pressure to give a dispersion G. 
The dispersion F, G and H were mixed with photographic gelatin solutions 
and coated, respectively, on photographic triacetate bases so that the 
coated amounts of gelatin and UV absorbents were equal. The optical 
densities at 370 nm and 415 nm of thus obtained specimens were measured 
with a spectrophotometer and the results are shown in Table 6. 
TABLE 6 
______________________________________ 
UV 
Gelatin 
absorbents Optical density 
(g/m.sup.2) 
(g/m.sup.2) 
370 nm 415 nm 
______________________________________ 
Dispersion F 0.55 0.20 1.60 0.43 
(Comparison 1) 
Dispersion G 0.55 0.20 3.00 0.11 
(Comparison 2) 
Dispersion H 0.55 0.20 2.88 0.11 
(Present invention) 
______________________________________ 
As is clear from above results, the UV absorbents impregnated dispersion 
prepared by the process of the invention shows a high level optical 
density in ultraviolet region and a clear cut-off characteristic in visual 
wave region, as compared with those prepared by the known 
protect-dispersion method. 
Further, the dispersion prepared by the process of the invention shows 
effects comparable to those prepared by the aqueous polymer latex 
dispersion method disclosed in Japanese Patent Publication No. 51-59943, 
as laid open to public inspection; while the amount of organic solvent 
used in the dispersing process of the invention was reduced to 1/5 and the 
time required for removing solvent was remarkably shortened. 
EXAMPLE 12 
To 100 ml of aqueous polymer latex (polymer concentration: 10% by weight) 
comprising illustrated copolymer No. 1 were added 100 ml of acetone. 
To the polymer latex containing the acetone were added, in one portion, 5 g 
of yellow dye-forming coupler, or 
.alpha.-(3-benzyl-2,4-dioxoimidazolidin-3-yl)-.alpha.-pivaloyl-5-[.alpha.' 
-(2,4-di-tert-amylphenoxy)butyramido]-2-chloroacetanilide in the form of 
crystals, with stirring. After additional stirring for 1-2 minutes, the 
coupler was completely dissolved. The acetone was removed under reduced 
pressure with a rotary evaporator to give a dispersion (Sample 4). For 
comparison, Comparison 1 used in Example 1 was employed here again. 
The transmittance at 530 nm (green light) for the representative figure of 
grain size of polymer dispersion, stability and time required for 
impregnation were measured with respect to both samples. The results are 
shown in Table 7. 
TABLE 7 
______________________________________ 
Sample 4 
Comparison 1 
______________________________________ 
Transmittance (530 nm) 
97.5% 93.0% 
Stability good a little poor 
Time required for impregna- 
tion 1.5 min. 2.5 min. 
______________________________________ 
Similar tests were conducted using 50 ml or 35 ml of acetone. In accordance 
with the process of the invention, a satisfactory impregnation was 
achieved with only 35 ml of acetone, while in comparison, precipitate was 
observed by visual observation with 50 ml or 35 ml of acetone. Sample 4 
and Comparison 1 showed no flocculation during storage and they were 
fairly comparable with gelatin solution. After mixing with gelatin 
solution, they were coated and dried, separately, on transparent 
photographic supports, giving transparent layers, respectively. 
EXAMPLE 13 
Following substantially the same procedures as in Example 12, except that 
aqueous polymer latex containing illustrated copolymer No. 28 was used and 
that acetone was replaced by tetrahydrofuran, there was obtained a stable 
polymer latex composition containing the impregnated coupler. 
EXAMPLE 14 
To 20 ml of aqueous polymer latex comprising illustrated copolymer No. 1 
(polymer concentration: 25% by weight) were added 15 ml of THF. To the 
mixture were added 5 g of cyan dye-forming coupler, or 
2-[.alpha.-(2,4-di-tert-amylphenoxy)-butyramido]-4,6-dichloro-5-methylphen 
ol as such, and after stirring for 1-2 minutes, the coupler was completely 
dissolved to give a homogeneous dispersion. 
After this, the coupler was immersed according to the method of the 
invention, using aqueous polymer latices having different polymer 
concentrations. 
Namely, 15 ml of THF were added to 17 ml of latex (polymer concentration: 
30% by weight) and then 5 g of cyan coupler, or 
2-[.alpha.-(2,4-di-tert-amylphenoxy)butyramido]-4,6-dichloro-5-methylpheno 
l were added as such. The stirring was continued for 1-2 minutes to give a 
homogeneous dispersion, dissolving the coupler completely. 
To the dispersion were added 30 ml or 33 ml of pure water. The THF was 
removed under reduced pressure with a rotary evaporator, and there were 
obtained, with no flocculation or precipitation of crystals, stable 
polymer latex compositions in which the coupler was impregnated. From the 
results, it has turned out that coupler-impregnated stable polymer latex 
compositions may be obtained by the process of the invention even when a 
concentrated aqueous polymer latex (polymer concentration: &gt;20% by weight) 
is used. 
EXAMPLE 15 
Following substantially the same procedures as in Example 14, except that a 
magenta dye-forming coupler, or 
1-(2,4,6-trichlorophenyl)-3-(2-chloro-5-octadecylfuccinimidoanilino)-tyraz 
olin-5-one, 30 ml. of a 1:1 volume mixture of acetone and THF as 
water-miscible organic solvent, and illustrated copolymer No. 6 (polymer 
concentration: 20% by weight) as aqueous polymer latex were used, 
respectively, there were obtained similar good results. 
EXAMPLE 16 
5 g of cyan dye-forming coupler, or 
2-[.alpha.-(2,4-di-tert-amylphenoxy)butyramido]-4,6-dichloro-5-methyl 
phenol were dissolved in a mixture of 5 g of dibutyl phthalate and 15 ml 
of ethyl acetate, and then 75 ml of gelatin solution containing 
alkylnaphthalenesulfonic acid (Alkanol XC, trade name, Dupont Co.,) as 
dispersing agent were added. The mixture was ultrasonic-dispersed by a 
usual method to give a dispersion A. 
Meanwhile, 30 ml of THF were added to 50 ml of aqueous polymer latex 
(polymer concentration: 20% by weight), and then 5 g of the 
above-mentioned cyan dye-forming coupler were added as such and stirred. 
By stirring the mixture for 1-2 minutes, there was obtained a homogeneous 
dispersion. 50 ml of pure water were added to the dispersion, and the THF 
was removed with a rotary evaporator under reduced pressure to give a 
dispersion I. After this a dispersion B was prepared in the same way as in 
Example 7. 
The thus obtained coupler dispersions A, B and I were mixed, respectively, 
with silver halide emulsions for red-sensitive paper and coated on 
photographic polymer film supports as follows: 
______________________________________ 
Comparison 2 
Comparison 3 
Sample 5 
______________________________________ 
Dispersion A B I 
Coupler (mg/dm.sup.2) 
7.4 7.8 8.0 
Silver (mg/dm.sup.2) 
4.1 4.2 4.5 
Gelatin (mg/dm.sup.2) 
38.2 39.0 40.5 
______________________________________ 
The specimens were wedge-exposed and developed at 25.degree. C. for 4 
minutes with a developer having the same composition as in Example 7, and 
the results are shown in Table 8. 
TABLE 8 
______________________________________ 
Relative speed 
D max .gamma. 
D min 
______________________________________ 
Comparison 2 
100 2.55 3.20 0.05 
Comparison 3 
89 2.41 3.01 0.03 
Sample 5 100 2.58 3.10 0.03 
______________________________________ 
From the above results, it has turned out that the color properties are not 
deteriorated by the process of the invention, using a low energy 
dispersion and a smaller amount of solvent, as compared with known 
processes. 
EXAMPLE 17 
The comparisons 2 and 3 and Sample 5 were processed in the similar manner 
as in Example 16 and subjected to acceleration tests at 50.degree. C. and 
80% relative humidity for 2 weeks. The rates of remained dyes of colored 
dyes at D max part were compared and the results are shown in Table 9. 
TABLE 9 
______________________________________ 
D max 
Before After Remaining 
processing 
processing 
rate Remarks 
______________________________________ 
Comparison 2 
2.55 1.90 76.4% turned to 
green 
Comparison 3 
2.50 2.23 90.0% 
Sample 5 2.61 2.38 91.2% 
______________________________________ 
As is clear from Table 9, Sample 5 according to the invention shows better 
image preservability than that of Comparison 2 and possesses 
characteristics comparable to those of Comparison 3. 
EXAMPLE 18 
A solution of 10 g of magenta dye-forming coupler, or 
4,4'-bis{1-(2,4,6-trichlorophenyl)-3-[3-(2,4-di-tert-amylphenoxyacetamido) 
benzamido]-pyrazolin-5-one} and 1.2 g of 
2-(1-phentyltetrazolyl-5-thio)-4-octadecylsuccinimido)indanone in a 
mixture of 10 g of tricresyl phosphate and 30 ml of ethyl acetate was 
added to 75 ml of 3.5% gelatin solution containing Alkanol XC (trade name) 
as a dispersant, and the mixture was protect-dispersed with a colloid mill 
according to a conventional method to give a dispersion D. 
Subsequently, 30 ml of a 1:1 by volume mixture of acetone and THF were 
added to 50 ml of aqueous polymer latex (polymer concentration: 20% by 
weight) comprising the illustrated copolymer No. 20. After this, 10 g of 
the above-mentioned magenta dye-forming coupler and 1.2 g of the DIR 
substance were added to the polymer latex, and stirring was continued for 
1-2 minutes to give a homogeneous dispersion J. 
The dispersions D and J were mixed with green-sensitive color negative 
silver iodobromide emulsions and coated on triacetate bases, respectively 
to make specimens as follows: 
______________________________________ 
Coupler Silver 
Dispersion 
(mg/dm.sup.2) 
(mg/dm.sup.2) 
______________________________________ 
Comparison 4 
D 9.2 12.0 
Sample 6 J 9.5 12.3 
______________________________________ 
The specimens were wedge-exposed and processed according to developing 
process for Sakura Color II 
The results are shown in Table 10. 
TABLE 10 
______________________________________ 
Relative 
sensitivity 
D max .gamma. 
Fog 
______________________________________ 
Comparison 4 
100 2.2 0.82 0.21 
Sample 6 98 2.1 0.79 0.18 
______________________________________ 
EXAMPLE 19 
To a mixture of 75 ml of aqueous polymer latex (polymer concentration: 20% 
by weight) identical with that used in Example 15 and 50 ml of THF were 
added 12 g of DRR compound which is identical with that used in Example 
10. After 1-2 minutes, the DRR substance was dissolved and the THF was 
removed under reduced pressure with a rotary evaporator to give a 
homogeneous dispersion. 
By using the above-mentioned polymer latex impregnated with the DDR 
compound, the following photographic element was coated according to the 
method disclosed in Japanese Patent Publication No. 47-126331, as laid 
open to public inspection. 
First, the dispersion was mixed with a negative silver bromide emulsion, 
then added a hardener and spreader, and coated on a polyester base to give 
the following photographic element: 
DRR compound, 1.2.times.10.sup.-5 mol/dm.sup.2 
Silver, 10.1 mg/dm.sup.2 
Gelatin, 35.0 mg/dm.sup.2 
Meanwhile, an image-receiving element was prepared in the same way as in 
Example 10. 
The mordant layer light-sensitive element was wedge-exposed and piled up on 
the image-receiving element and the resulting sandwitch structure was 
passed through a pair of press rollers to introduce a viscous processing 
solution having the same composition as in Example 10. 
After 90 seconds, the image-receiving element was stripped off and washed 
with water to adjust pH to 7. A good cyan printed image was obtained on 
the image-receiving element. 
For comparison, a similar test was performed, using an identical specimen 
except that diethyl laurylamide was used as a high boiling point solvent 
in place of the polymer latex and that a DRR compound dispersion was 
obtained according to a known dispersing method. 
The comparative results are given in Table 11. 
TABLE 11 
______________________________________ 
Relative 
sensitivity Fog D max 
______________________________________ 
Comparison 100 0.20 1.84 
Present process 
102 0.18 1.85 
______________________________________ 
Quite comparable sensitometric effects were obtained. 
EXAMPLE 20 
Dispersion F and G were prepared in the same manner as in Example 11. 
Meanwhile, 8.5 g of mixed UV absorbents having the same composition as in 
Example 11 were added, as such, to a mixture of 30 ml of aqueous polymer 
latex comprising the illustrated compound No. 6 (polymer concentration: 
20% by weight) and 20 ml of THF to make a colloidal, homogeneous 
dispersion K. 
The dispersions F, G and K were separately mixed with photographic gelatin 
solutions and coated on photographic triacetate bases so that the coated 
amounts of gelatin and UV absorbents were equal. 
The optical densities at 370 nm and 415 nm of thus obtained specimens were 
measured with a spectrophotometer and the results are shown in Table 12. 
TABLE 12 
______________________________________ 
Gelatin 
UV absorbent 
Optical density 
(g/m.sup.2) 
(g/m.sup.2) 
270 nm 415 nm 
______________________________________ 
Dispersion F 
0.55 0.20 1.60 0.43 
(Comparison 1) 
Dispersion G 
0.55 0.20 3.00 0.11 
(Comparison 2) 
Dispersion K 
0.55 0.20 2.98 0.10 
(present invention) 
______________________________________ 
From the above results, Dispersion K according to the process of the 
invention shows a UV absorption at a very high level and a sharp cut-off 
effect at a visual wave region, comparable to those prepared by the method 
disclosed in Japanese Patent Publication No. 51-59943, as laid open to 
public inspection. 
EXAMPLE 21 
Tests were conducted following substantially the same procedures as in 
Example 20, except that an aqueous polymer latex comprising the 
illustrated compound No. 29 was used in place of Compound No. 6 and that 
the amount of the UV absorbents were reduced to 1/4. The results revealed 
that nearly the same tendency was observed as in Example 20.