CA1145081A - Process for preparing impregnated polymer latex composition - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Preparing a loaded polymer latex composition by mix-ing a polymer particle dispersed in an aqueous polymer latex, a hydrophobic substance, a water-miscible organic solvent and a water-immiscible organic solvent thus loading the polymer par-ticle with the hydrophobic substance. With this process no dispersing apparatus with high energy is required. The composi-tion is not subject to change in properties attributable to the action of heat. Layers formed can be made thinner. The burden imposed on drying the composition is reduced. Solvent removal is performed in short time. Composition is stable.

Description

s~38~

PROCESS FOR rREPARING IMPREGNA~ED POLYMER LA~EX COMPOSITION

~ his invention relates to a process for loadirg a dispersed polymer particle present in an aqueou~ polymer latex with a hydrophobic substance and particularly to a process for preparing a polymer latex composition loaded with a photo-graphic hydrophobic additive.
In a step of preparing light-sensitive silver halide photographic materials, there have heretofore been adopted several procedures to uniformly distribute various hydrophobic compounds, particularly such compounds as dye forming agents, ultraviolet absorbing substances, etc., throughout gelati~ or other hydrophilic colloid solutions. As one of the above-mentioned procedures, there is a process in which a solid or liquid hydrophobic compound (I) is mixed with a hydrophobic colloid solution (II), the resulting mixture is passed several times through a high energy mill such as colloid mill, thereby mechanically dispersing (I) in (II) to prepare a dispersio~, and the dispersion i9 then dispersed in a hydrophilic colloid solution. In this process9 however, a poorly dispersed state is liable to occur and in such case the resulting poor dispersion is often found unstabls. According to this process, moreover, large amounts of ener~y are needed in order to pulverize the compound (I) to a desirable extent and ~uffi-ciently disperse the pulverized compound i~ the h~drophilic colloid solution. Consumption of ~uch large energy is often ~5~1 accompanied by excessive accumulation of heat or undesirable local heating, and these cauæe an undesirable chemical chanKe of the ingredients present in a system.
Further, U.S. Patents 2,~04,940 and 2,322,027 disclose another process for dispersing hydrophobic compounds in hydrophilic colloid solutions. That is, in this process the hydrophobic compound is first dissolved in oil or în a high boiling solvent to prepare an oily solution and the thus obtained oily solution is then dispersed in a hydrophilic colloid solution. As a modification of the above process there is a process a~ disclosed, for example, in U.S. Patent

2,801,171. In this process, there is sometimes used a low molecular solvent, such as ethyl acetate or a low molecular ketone, as an assistant to an oily solvent for facilitating dissolution in the oily ~olvent of a hydrophobic substance.
In a process for the preparation of silver halide color photo-graphic emulsions incorporated with ballasted dye forming agents (the dye forming agents are hereinafter called "couplers"), there is widely adopted a process in which the ballasted couplers are dissolved in oily and high boiling solvents k~own as solvents for couplers, and the resulting solutions are then dispersed in hydrophilic colloid solutions such as gelatinou~
silver halide emulsions. In such dispersing procedure as mentioned above, however, a pulveriz~tio~ step of high energy 8~L

is necessary in order to obtain a desirable state of dispersion and particle size of the coupler, and usually certain ingre-dients present in a composition being subjected to such pulverization step are eventually liable to deterioration ~uch as thermal decomposition or the like. Further, such pulveriza-tion step requires much time for its completion and raises its operation cost~ On this account, the advent of an improved dispersing process has been a desideratum, accordi~g to which process hydrophobic compounds ~uch as ballasted couplers 7 etc~
can uniformly be dispersed in photographic emulsio~s a~ well as in other hydrophilic colloid solutions. In such improved process, however, the use of the high energy milles which have heretofore been employed in order to disperse the hydrophobic compounds in the hydrophilic colloid solution must be excluded from the process step.
Japanese Patent Publicatio~ No. 30494/1973, on the one hand, discloses the use of polymers, which are insoluble in water but soluble in organic solvent~, for dispersing hydro-phobic couplers for the purpose of improving photographic properties (e.g. image preservability). In this case, too, it was necessary to use a high energy mill in order to emulsify the polymer incorporated with the couplers. Under such circumstances, Japanese Laid-Open-to-Public Publication~ NosO
59942/1976 and 59943/1976 disclose a technique aiming at avoidance of the use of such high energy mills as bringin~ about the above-mentioned disadvantages and further at impartation of various advantages to photographic emulsions. ~hat is, accord-ing to this technique, there is used a process wherein a polymer latex comprising dispersed polymer particles individually loaded with hydrophobic substances is dispersed in a hydrophilic colloid solution so that the h~drophobic substances are dispersed whilst in a state o~ loading of the dispersed polymer particles with said ~ydrophobic substances in the hydrophilic colloid solution. B~ virtue of the use of such polymer latsx9 some desirable properties are imparted to the resulting silver halide photographic emulsions. That is, as compared with photographic emulsions obtained by application thereto of the conventional dispersing processes ~ particles of the resulting dispersion containing couplers are made small in size, with the result that the resulting image is improved in sharpness and reactivity between the developing ag~nt and couplers are improved. Further~ it ha~ become possible that hydrophobic compounds, which have been desired to be dispersed in hydro-philic colloid solutions but could not be made so because of their liability to oxidation by air, can be introduced i~to the hydrophilic colloid solution by virtue of application of this process wherein the hydrophobic ccmpounds ca~ satis~actorily be protected from being subject to oxidation. Still further, such hydrophobic compounds, which are excessively high in reactivity and undesirably react with other ingredients present in a layer containing said hydrophobic compou~ds, have also been able to be incorporated into hydrophilic colloid solutions by virtue of using the polymer latex. In the manner above explained, the process using the polymer latex as a dispersion carrier for photographic additives is a technique which is capable of impart~ng the above-mentioned excellent photographic character-istics to the photographic emulsio~s to which said process has been applied without usi~g any high energy mill~ In this process, however, it can be pointed out that there remain problems for solution.
First of all, in the processes of the inventions disclosed in the aforesaid Japa~ese Laid-Open-to-Public publicatio~s, the amounts of hydrophobic substances which can be loaded in dispersed polymer particles of the polymer latex were not sufficient. ~hat is, in case couplers which are typical of the photographic hydrophobic additives are loaded in the particles dispersed in the polymer latex, it is necessary to use said dispersed particles in an amount greater than that of the couplers or in certain cases more than 2 times that of the couplers~ with the result that the photographic material thus prepared becomes large in film thickness to bring about degradation in developability or low resolvi~g power thereof.

~5~:38~

Further, the conventional processes have such drawbacks that because of a low concentration of dispersion particles present in the polymer latex used, largè amounts of the polymer latex liquids are needed and on that account an increased b~den i9 imposed on dl~ying the liquids. Still further, there are such drawbacks that when the dispersion particles are loaded with hydrophobic substances, the use of a relatively lar~e amount of a water-miscible organic solvent becomes necessary with the result that an apparatus for the removal of said solvent becomes large in its scale and much time is required for removing the solvent. In addition thereto~ there are such drawbacks that the usable polymer latexes are considerably limited in kind and the loaded polymer latex compositions obtained are not alwqys sufficient in stability. ~ stated hereinbefore, none of the known processes gave satisfactory result~ heretofore.
The present invention has been intended to solve the above-mentioned various problems inherent in the prior art processes, and a primary object of the invention is to provide a process for prepari~g a polymer latex composition loaded with a hydrophobic substance free from the above-mentioned drawbacks, said process being performable without relying on the use of hi~h energy. A second object of the present invention is to provide a process for prepari~g a polymer latex compo~ition, the dispersion particl~s o~ which composition has been loaded ~5$8~L

with large amounts of hydrophobic substances. The third object of the invention is to provide a process for preparing a loaded polymer latex composition having used therein a polymer latex containing the particles dispersed in high concentration. The fourth object of the invention is to provide a process for preparing a loaded polymer latex composition, wherein the loading of dispersion particles of the polymer latex with hydrophobic substance being easily performable and the removal of a solvent after loading being effective. The fifth object of the invention is to provide a process for preparing a loaded polymer latex composition, wherein the polymer latices used are not so strictly limited in kind.
Extensive researches prosecuted by the present inventors for accomplishing the abovementioned objects have eventually resulted in the ~inding that the aforesaid problems can be solved by loading dispersed polymer particles with hydrophobic substances in the presence of three media, i.e.
water, a water-miscible organic solvent and a water-immiscible organic solvent, and the present invention has been accomplished by the present inventors on the basis of this finding.
More particularly, according to the invention, there is provided a process for incorporating a hydrophobic substance into a hydrophilic colloid solution, comprising mixing a polymer particle dispersed in an aqueous polymer latex, the hydrophobic substance, a water-miscible organic solvent and a water-immiscible organic solvent whereby the polymer particle is loaded with the 5~381 hydrophobic substance, and incorporating the polymer particle loaded with the hydrophobic substance into the hydrophilic colloid solution.
According to the process of the present invention for the preparation of a loaded polymer latex composition, there can be obtained such excellent effect as mentioned below.
(1) Since no dispersing apparatus with high energy is - 7a -~.`
~.' , ~

.

~5~

required, there is no possibility of the resulting composition being subject ~o change in properties attributable to the action o~ heat generated.
(2) Since large amounts of the hydrophobic substances can be contained by loading in dispersed polymer particles present in the compositio~, the layer formed by the use of said composition in the photographic material can be made thinner i~ dry film thickness with the result that both developability and resolving power are improved.

(3) Since an aqueous polymer latex having a hi~h concentration of the latex can be used, the burden imposed on drying the composition can be reduced.

(4) Since the ~mount of an organic solvent used in the loading step can be minimized, removal treatment of the solvent is readily performed in a short time without necessitating a removal apparatus of great size.

(5) The aqueous polymer latexes usable in the present process are not so strictly limited in kind a~d accordingly such hydrophobic substa~ces as could not be contained by loading in aqueous polymer latexes can be used and, more-over, the loaded polymer latex compositions obtained are quite stable.
In embodiments of the present invention, where dispersed polymer particles present in an aqueous polymer .~.

~S~8~

latex are loaded with hydrophobic substances according to the present process in the presence of three media, i~e. water, a water-miscible organic solvent and a water-immiscible organic solvent, the mixing order of these components, as will be fully explained later in examples Or the present invention, may be subjected to various modifications and hence i~ suitably decided.
In short, an indispensable requisite is the presence of the three components, lOe. water, a water-miscible organic solvent and a water-immiscible organic solvent, and the mixin~ order of these components is not critical.
Most preferable as the water-mi~cible organic solvent used in the present invention are those which are miscible with water in any proportion7 howeverl those as having their miscibility of 2~/o by weight or higher in water can be used for accomplishing the purposes of the present invention. The water-immiscible organic solvent referred to herein includes those a~
having their miscibility of not more than 2~ by weight, preferably less than ~0~ by weignt in water. Because of removal after loading ~tep, these two kinds of organic ~olvents have not 30 high boiling points, such as below 200C., preferably below 100C. Such water-mi~cible organic solvent as mentio~ed above includes, for exampleg acetone, methyl eth~l ketone~ ethyl alcohol, methyl alcohol~ i60propyl al¢ohol, tetrahydrofuran, N-methylpyrrolidone, dimethylformamide a~d dimet4yl~u1~oxide, ~45~

though the usable solvents are not limited to those exemplified herein. The water-immiscible organic solvent referred to above includes, for example, ethyl acetate, n-butyl alcohol, chloroform, carbon tetrachlorida, et~yl chloride, et4ylene chloride, dibromoethane, n-propyl acetate, n-butyl acetate, sec~
butyl acetate, cyclohexanone, cyclohexanol, ethylene ~lycol monomethyl ether, i~o-butyl alcohol7 n-amyl alcohol, iso-amyl alcohol, sec-amyl alcohol~ diethyl ether, diisopropyl ether, meth~l-n-propyl ketone, methyl-n-butyl ketone, be~zene, tolue~eq xylene and benzyl alcohol ? though the usable solvent~ are ~ot limited to those exemplified herei~.
Furthermore, as a part o~ the water immi~cible ~olvent, there can also be used a high boiling orga~ic solve~t which has heretofore been used in the so-called protect dispersion process and which is substantially immiscible with water~ By virtue of the use of such high boiling solvent as referred to above, the photographic materials can be improved in color characteristics and other photographic properties. Examples of such hiæh boiling organic solvent are, for example, dibutyl phthalate, tricresyl phosphate~ triphe~yl phosphat~, diathyl laurylamide and dioctyl phthalate.
~ he proportions of the above-mentioned water-miscible organic solvent a~d watar-immiscible organic solvent to a~
aqueou~ polymer latex u~der the optimum condition~ may vary /

~ ~ ~ 5 depending on the kind of polymer substance present in an aqueou~
polymer latex or hydrophobic substance used. Generally, ths proportion of aqueous polymer latex : water-miscible organic solvent is 1 : 0.1 - 10, preferably 1 : 0~5 - 3 or thereabout~.
The proportion of water-mi~cible organic solvent : water-immiscible organic solvent is 1 : 0.01 - 1, preferably 1 : 0~03 - O.5 or thereabouts~ ~he wa~er-miscible organic solYent and water-immiscible organic solvent may individually be u~ed in combination with other water-miscible a~d water-immiscible organic solvents, respectively, in the form of admixtur~ of two or more.
~ he hydrophobic substance referred to in the present invention includes those as having their solubility of about 1%
in water.
Examples of such hydrophobic sub~tances include many materials, including agricultural chemicals, medicines, dye~
etc. and photographic hydrophobic additives are placed i~ the same category, as well.
~ ypical of the photographic hydrophobic ~ubstances usable for impregnation purposes in accordance with the present invention are couplers, ultraviolet absorbers, developme~t inhibitor releasing materials, cross oxidatio~ type dye releasing agents and photographic dyes, and there may also be used fluorescent brightening agent~, a~tihalation or , 5~8~L

anti-irradiation agentst developing agents, etc.
More particularly, the couplers include, for example, open chain methylene type yellow couplers~ 5-pyrazolone t~pe magenta couplers9 phenol or naphthol type cyan couplers, etc.
~hese couplers may be either the so-called 2-equivalent type or 4-equivalent type couplers, and they may also usable in combi-nation with couplers for automasking such as azo type colored couplers, osazone type compounds 7 diffu~ible dye releasin~ type couplers, etc~ Further, in order to improve photographic characteristics, the hydrophobic couple~s referred to above ma~
be used in combination with other couplers know~ as the ~o-called competing couplers, DIR couplers (De~elopment IDhibitor Releasing Couplers) a~d BAR couplers (Bleach Accelerator Rsleasing Couplers).
The yellow couplers include open chain ketometh~lene compounds which have heretofore bee~ used~ For example, pivaoyl acetanilide type yellow couplers include those as disclosed in U.S. Patent 3,265,505, benzoyl acetanilide type yellow couplers include those as disclosed in the specifications of British Patent 1,240,600 and U.S. Patent 2,875,051. ~urther7 effec~
tively usable yellow coupler~ k~own as the so-called 2-equivale~t type couplers include active-point -0 - aryl-~ubstituted couplers disclosed i~ U.SO Patent 3,408,194, active~poi~t-0-acyl-substituted couplers in IJ.S~ Patent 3,447,928, ~ctive point .

~ ~ ~ S~ 8~

hydantoin compound substituted couplers in British Pate~t 1,351,424, active-point-ura30l-compound-substituted couplers and active-point-succinic-acid-imide-compound-sub~tituted couplers in British Patent 1,331,179, active-point-monooxoimide-compound-substituted couplers and active-point-fluorine-substituted couplers in British Patent 944,490, active~point~chlorine or-bromine substituted couplers in British Pa~ent 7809507, and active-point -0-sulfonyl-substituted couplers in British Patent 1,092,506.
Further usable as the mage~ta couplers in the present invention are compou~ds o~ pyrazolone typ~ pyrazolotria~ole type, pyrazolinobenzimidazole type and. indazolone type. The pyrazolone type magenta couplers include those disclosed in U~S.
Patents 3,127,269, 2,600,788, 3,519,429, 3,419,391 and 3,062,653, and British Pate~ts 1,342,553 and 1~399,306, and U.S. Pa-tent 3,684,514. ~he pyrazolotriazole type magenta couplers include those disclosed in British Pate~ 17247,493, and the pyrazolino-benzimidazole type magenta couplers i~clude those disclosed in U.S. Patent 3,061,~32, and the inda30l0~e type ma~enta couplers include those disclosed in British Patent 1,335,603. ~urt~er, particularly suitable magenta couplers for the process of the present invention include those disclosed in U.S. Patent 3,684,514 and U.S. Patent 3,127,269.
Useful cyan couplers u~ed in the prese~t i~vention include phenol compounds disclosed7 for example, in U.S~ Patents 2,423,730, 2~801,171 and 2,895,826, active-point -0- aryl-substituted naphthol compounds disclosed in U~S. Patent 2,474,293 and British Pate~t 1,0&~,4809 and phenol and naphthol compounds disclosed in Canadian Patent 913,0a2 and U.S. Patent 3,737,~16.
As the colored magenta couplers, there may be used such compounds having arylazo substitutio~ or heteroarylazo substitution at the active point of colorless magenta coupler as disclosed, for example, in U.SO Patents 3,005,712, 2,983~608 and 2,801,171, British Patent 937,621 and U.S. Patent 3,6841514.
Usable as the colored cy~n couplers are such compounds having active-point-arylazo~substitution as disclosed in U.S.
Patents 3,034,892 and 2 t 521,908, British Patent 1,255,111 and U.S. Patent 3,811a892, and such masking couplers of the type in which on reaction with an oxidized developing agent a dye elutes out into a processing solution as disclosed in British Patent 1,084,480.
Further, usable as the competing couplers are those disclosed in U.S. Patent 2,742,832, for example, citrazinic acid, etc., and those disclosed in U.S. Patent 2~998,314 or the like.
Preferably usable a~ the development inhibitor releasing substances are those disclosed in U.S. Patent~

_ 14 -~s~

3,632,345, 3,928,041, 3,958,993 and 3,961,959.
Usable as the ultraviolet absorbers are triazoles, triazines or benzophenones known from U.S. Patents 3,004~896, 3,253,921, 3,533,794, 3,292,525~ 3,705,805, 3,738,837 and 3,754,919, and British Patent 1,321,3559 and Japanese Laid-Open-to-Public Publication No. 252~7/19750 ~urthermore, in addition thereto, usable are acrylonitrile type compounds as disclose in U.S. Patent 3,052,636 and 3,707,535. Preferably usable as the ultxaviolet absorbers are those sold by Ciba-Geigy of Swit7.erland under the trade names of ~inuvin S 320, 326~ 327 and 328, either singly or in combination. Further, there may also be used azoles disclosed in U.S~ Patents 2,537,877t 2,739,9719 2,739,888, 2,784,087 and 3,250,687 or high molecular type triazine compounds as disclosed in U.S~
Patents 3,512,984 and 3,549,374.
In addition to those explained hereinbefore, the photographic hydrophobic additives usable for the loading purpose in accordance with the present invention are photo-graphic dyes as disclosed in U.S. Patents 2t751,298 and 3,506t443, DDR couplers (Diffusible Dye Releasing Coupler~) as disclosed in U.S. Patents 3,443,939, 3,443,940, 3,343,941 and 3,7~5,062, indicator dyes as disclosed in U.S. Patent 3,647t437, sulfonamidophenols, reducing agents, as di~clo~ed in U.S. Patent 3~810,321, reductones as disclosed in U.S.

~ 81 Patents 3,572,~96 and 3,679,426, bisnaphthol reaucing agents as disclosed in U.S. Patents 3,672,904 and 3,751,294, hydrophobic developing agents as di~closed in U.S~ Patent 3,672,896, 3,672,9Q4, 3,679,426 and 39751~249 and the so~called cross oxidation dye releasing agents known as DRR materials (Dye Releasing Redox Materials) as disclosed in U.S. Pate~ts 3,628,952, 3,698,897 and 3,725,062, and Belgian Patents 788~268, 796,040, 796,0~1 and 796,042.
~ he aqueous polymer latexes containing dispersed polymer particles used in the present in~ention should be such that when they are incorporated with a water-miscible organic solvent and a water-immiscible organic solvent 9 no aggregation nor precipitation o~ the dispersion particles is brought about and said dispersion particles are stably dispersed in the latex~
~urthermore, these aqueous polymer latexes are preferably those which when incorporated into such hydrophilic colloid solution as gelatin do not cause aggregation nor precipitation of the dispersion particles and, whe~ coated on a support and then dried, form transparent films.
Such a~ueous polymer lat~xes as mentioned above can be prepared by emulsion copolymerization or radically polymer-izable ethene monomers, and the polymer contains therein at least one compound having such hydrophilic group as sulfo, sulfonate, sulfonyl, carboxy, carboxylate, hydroxy, amido, sulfonamido, quaternary ammonium, polyalkyleneoxide and sulfate.
The amount of the compound containing the hydrophilic group to be contained in the polymer is usually up to 5~/O~ but the monomer compound having a hydroxy group as a hydrophilic group can be incorporated in an amount up to 7~/O. In accordance with the present invention, moreover, an aqueous polymer latex high in concentration of dispersed particles can be used and hence those having the dispersion product concentration of up to 6~/o by weight are usable. Moreover, the polymer particles may contain 0.2 to l~/o by weight of a monomer unit having an active methylene group.
As mentioned above, the aqueous polymer latices used in the present invention are prepared by emulsion copolymeriza-tion of radically polymerizable ethene monomers. Examples of the usable monomers in that case are exemplified below but are not limited to those exemplified.
1) Acrylic acid ester compound:
Methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, glycidyl acrylate, 2-acetoacetoxy-ethyl acrylate, etc.

2) Methacrylic acid ester compound:
Methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecylmethacrylate, glycidyl methacrylate, 2-acetoxyethyl methacrylate, etc.
3) Acrylamides:-Butyl acrylamide, N,N-diethyl acrylamide, ~ - 17 -1~

8~

N,N-diisopropyl acrylamide, dodecyl acrylamide, etc.
4) Methacrylamides:
Butyl methacrylamide, N,N~diethyl me-thacrylamide, dodecyl methacrylamide, N,N-diisopropyl methacrylamide, etc.
5) Vinyl ester compound:
Vinyl acetate, vinyl butyrate, etc.

6) Halogenated vinyl compound:
Vinyl chloride, etc.

7) Halogenated vinylidene compound:
Vinylidene chloride, etc~

8) Vinyl ether compound:
Vinyl methyl ether, vinyl ethyl ether, vinyl he~yl ether, vinyl glycidyl ether, etc.

9) Styrene compound:
Styrene, ~-methyl styrene, hydroxy styrene, chloro3tyrene, methyl styrene, etc.

10) Other compounds:
Ethylene, propylene, butylene, butadiene, isoprene, acr~Lonitrile, etc~

11) Compounds having bydrophilic groups:
(1) CH2 = C - R
COO(CH2)3~3M

o ~5~

(2) R

CO~H( CH2) 2S03M

(3) R
CH2 I Cl H3 (4) R
CH2 lC
COO ( CH2) 4~03M

(5) CH2 ~ CH

(6) CH2 = CH
~,D

,. .

~5C~

(7) R
CH~, _ C
o a = o W` SO~M

(8) CH2 = CH
CONH~OCH3 (9) R

COOCH~

( 10) CH2 = CH
100CH~SO3M

(11) R

CoocH2cHcE2so3M
OH

~45~

( 12) CH2COO( CH2) 3SO3 C~I2 = C
3)3 3 (13) R

~0 ( 14) R
CH2 Cl ~OO(C~2)2 (15) R
CH2 F o C= o lH2 ~

( 16) R

C1~3 OH O
-- 2'1 --~5~

(17)R
CH = C
2 1 ~1 COOCH2CHCH2 - N~
OH O

(~8)X
CH2 lC

(19)R
CH = C
CO~HC ~ CE13) 3 (20)R
CH2 = C CH3 (21)R

COOCH2fHCH2NC ( CH3 ) 3 OH ~3 . ~
.

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(22) R
CH = C CH3 COOCH2~ - C~2SO ~;
C~3 ~23) R
c~2 Ic IC03 e COOCE 2CH21~ CH2C~I2S3 CH~

(24) R

COO ( CH2~ 20H

( 25) R

OH OH

(26) R
CH2 ~C
COO( OH2) 30~I

-- ~3 --8~

(27) R

I

CoocH2cH2ocH2c 2 (28) R
CH2 lC Cl H20H

aH2H

(29) R

I

CO()M

( 30) CH2COOM
CH2 lC
COOM

( 31 ) CH2 C CH
COO(C~I2)20CO ~ COOM

(32) R
CH = C CH
21 1~3 ~3 2 ~

-- 2~ _ 8~L

(33~ R

COO ( CH2CH20) 2S03M

(3~) R

CH = C

CONHCH2aH ~ - (CH2)3S03 (CH~5)2 (35) CH2 = CH
~2NH2 (36) CHCOO(~H2)3S03M

CHcoo(cH2)3s03M , ~tco In the above formula~, R repre~ents a hydrogen atom or a lower alkyl group and M repre~ents ~n alkali metal, a hydrogen atom or -NH4~
Exa~ples of the copolymerized polymer to be contained in the agueous polymer latex used in the pre~ent i~vention are exemplified below, but the u~able copolymerized polymer~ are not limited to those a~ ex~mplified.

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) ~ CH2 - CIH ~7Q ~ CH2 - CH ~10 CC2~I5 cooC~2cH2cH2 3 MW: 120,,000 2) t CH2 - CIH ~95 t CH2 - CH ~
COOCH2CI HCH3 CONHC2H5S03~a CH3 ~ 105 ~ 000 3) ~ CH2 - CH ~5 ~ CH2 - CH t COOCH?CH2CH2 CH2 - ICH ~0 ~03Na MW: 75, 000 4) t CH2 - CH ~0 t CH2 - CH ~0 COOCH3 CONH2 MW: 98, 000 5) CH3 ~ CH2 - CIH to ~ CH2 1 ~.5 COOC2H5 COOC~2CH~ H2 CH2 - IC ~8.5 COOCH2CH - CH2 MW:110,000 OH OH

~5~

6) t CH2 - ICE ~Q ~ CH2 - CH
COO(CEI2) 3CH3 COOCH2CH~

CH2 - CH ~7 CONHC3~6~;03~a MW: 68 7 000 7) CH3 CH2 ~ iH ~85 ~ CH2 IC ~5 CH3 MW: 87,000 8) ~ CH2 Cl ~75~ CH2 - CH ~5 CH2 - Cl ~0 CCH2CH2CH2~3~a MW: 73, 000 9) ~ CH2 - CH t70 ~ CH2 CH ~20 CH2 - CIH ~o MW:66,0QO
CO~

5~8~

10) ~ CH2 - CH ~o ~ CH2 ICH ~25 ~ 2 1 15 COOC2H5 OCOCH3 S03Na MW:75,000 11) ~ CH2 - CIHt COOC2H5 MW: 120, 000

12) t CE2 - IH ~90 ~ CH2 - IH ~1~03~a COOCH2CH2CH3 COl~H
CH3 MW: 91, 000

13) ~ CH2 - CH ~5 t CH2 1 5 C~I2 - lC ~o coocH2cHcH2so3~a MW :1 1 3 , 000 OH

14) t CH2 - CHt~o ~ CH2 - Cl~ ~2.5 COOCH2CH - CH 3, COOCH2CHCH2 t CH2 - CH ~17 . 5 COOCH2 ICH I 2 ~ 140,000 OH OH

~S~8~L

15) --~ CH2 - CH ~95 ~ C~2 l t5 COOC~I3 C00 ~
S03~a MW : 84 , 000

16) ~ CH2 - Cl~ ~85 t CH2 - CH ~15 C00(CH2)3,cH3 ¦ C~3 CO~H - C - C~ SO~a MW: 136,000

17) G~I3 CH2 - CIH ~80 t CH2 - I ~5 COO( CH2) 3C~I3 COOCH2CH2 OCOC~2CN
CH2 - CH ~15 S071~a MW:102,000 . .

5~81

18) CIH3 t C~12 - ICH ~o ~ CH2 ~ 1 ~5 OCOCH~,COCH3 CH2 - CH~5 COO~a rIW: 98, 000

19) ~ CH2 ~ CH t85 t CH2 - IH ~jo COO( CH2) 3CH3 Cl CH2 - CH ~
COONa ~1~: 156,000

20) t CH2 - CH to ~ CH2 CIH ~0 COOC2H5 COOCH2CHCH2SO ~ a OH
MW: 117,000

21 ) CH~;
CH2 - CIH ~0 t CH - C ~40 COO ( CH2 ) 3CH3 COO ( CH2) 20H
MW: 102 ,000 -- ~ --

22) CH2COOM
CH2 - CH ~() ~ CH2 - Cl ~o COOCHCH2C~I3 COOM
3 MW: 94 ) 000

23) IC~3 t CH~ - IcH t80 t CH2 - C ~20 1~3~3~3 COOC2H5 COOCH2 ~ CH2CH2~303 MW:72,0()0

24) ~ CH2 - CH ~o ~ CH2 1 ~0 COOCH3 ~0 MW: 87,000

25) ~ CH2 - CH t80 CH3 t CH2 - CH ~5 COO -- Cl - CH3 CH2 - C ~5 CoocH2clHcH2Nc(cH3) ~
OH ~ 88, 000 5~8~il

26) ~ CH2 CH ~75 ~ CH2 - CIH t25 ¦
COOCH3 COOCE~2Cl CH2H

MW: 88,000

27) ~ CH2 - CH t85 ~ CH2 1 ~15 COOC2H5 S02~EI2 MW: 107 ,000

28) Cl H3 ~ CE~2 - CIH~90 t CH2 - Cl ~10 COO ( CEI2 ) 3CH3 COOH
MW: 81 ,000

29) CIH3 CH2 - CIH ~60 ~ CH2 - lC ~3.5 C(C~2) 3CH3 COOCH2C~H~CH2 CH - I ~36-5 OHOH
MW:65,000 8~

30) CH~
-~ CH2 - CH ~-50 -~ C~2 1 10 COOCH3 CCH2CH~H2 i CH2 - C-~-40 CoocH2lcH - ICH2 OH OH MW:78,000

31) ICH3 -~ CH2 - CH-t-80 -~ CH2 - I ~ 5 C~I3, COOCH2CHCH2S03 C~3 t CH2 - C ~5 COOCH2CH20COCH2COCH~ MW:83,000

32) ICH3 t CH2 - CH ~ 5 t CH2 - C t5 COOCH2CH2C:~2CH3 COOCH2CH2CH2S03~a MW:79,000

- 33 -~5l31 3~L

33) -~ C~2 IH ~ 5 CH2 C ~
CCH2CH2CH2S3Na ~W:82 7 ooo 3~ CH2 - CH ~-90 COOCH2CH2CH2C~I3 t CH2 - CH ~-5 COOCH2C~20COCH2COC~I3 t CH2 ~ C ~
COOCH2CH2CH2S03Na MW:78,000 (MW represents a molecular wei~ht of a polymer.) ~ he aqueous pclymer latexes u~ed in the present invention can be prepared by emulsion copolymerization7 per se, kuown. ~or instance, the aqueous pol~mer latex can be synthe~ized is such a man~er that into deaerated ditilled water to which are added, if nece~sar~, an emulsifier~ a pol~meriza-tion initiator, a polymerization accelerator ~nd a polymeriza-tion regulator i~ incorporated 10 to ~/o b~ weight of the - 3~ -8~

predetermined monomer~, and ~he resulting mixture i8 heated to ~0 to 90C., followed by stirring for several hour~.
The emulsifier usable in the above cass may include, for example, anionic surface active age~ts such as ~odium alkylbenzenesulfonate 9 polyethylene oxide alkylether sulfate sodium, etc~, nonionic surface active agents such as poly-ethylene oxide alkylether~ etc., amphoteric surface acti~e agents such as those of betaine type or ~ulfobetaine type, and catio~ic surface acti~e age~t~ such as quaternary ammonium salts, etc., and these surface activ~ agents may be used either singly or in combination. Usable as the polymerization initiators are ammonium persulfate~ potassium persulfate, ydrogen peroxide, etc~, and usable as the polymerization initiation accelerators are sodium acid sulfite, sodium acid carbonate, etc. Usable polymerization regulator~ include, ~or example, mercaptan compounds, isopropanol, tertiary butanol, etc. In addition thereto~ if necessary, any other additives which bring about preferable results i~ the synthesis of the aqueous polymer latex may also be u~ed. The dispersed polymer particle8 present in the aqueou~ polymer latex obtained i~ the procedure above explained preferably have a particle diameter of about 0.01 to about 1 ~, though the particle diameter may vary according to the kiud and amou~t of the emulsifier added, the kind and amount of the monomers used, the kind and amount - ~5 -of the polymerization initiator added, and the syrthesis conditions (e.g. temperature, time, stirring speed, etc.).
~he concentration of polymer material present in the aqueous polymer latex used in the present invention is preferably from 5% by weight to 60% by weight, more preferably ra~ing from 30% by weight to 5~ by weight.
Typical examples of the aqueous polymer latex used in the presert ir,vention are illustrated below with reference to synthesis examples~
Synthesis Example 1 (Aqueous dispersion containing e~emplified copolymerized polymer 1) In a 2 liter four-headed flask (each head being equipped with a thermometer and a reflux condenser, a 300 ml dropping funnel (A), a 300 ml dropping fu~nel (B) and a stirring apparatus) were placed 2 g of an anionic ~urface active agent, Newrex R (a trade name of sodium dodecyl-ben~en~ulfonate produced and sold by ~is~an Kagaku Co., Ltd,) and 600 g of distilled water, and thereinto wa~ i~troduced nitrogen gas for 30 minute~, followed by elevating the inside tempcrature of the flask to 80~C. Subsequently, to the flask were added 0.5 g of ammonium per~ulfate and 0~2 g of sodium acid sulfite and, immediately thereafter were simulta~eousl~
added dropwise over 30 minute~ 161.7 g o~ ethyl acrylate ~5~

through the funnel (A) and 200 ml of an aqueous solution of 3B.7 g of sodium 3-acroyloxypropane-1-sulfonate through the funnel (B). After completion of the dropwise additio~, stirring of the flask was continued for 1 hour. Subsequently, the inside temperature was allowed to fall to room temperature to terminate the reaction~ A polymer material concentration in the aqueous polymer latex thus obtained was 20% by weight, and a particle diameter of the dispersed pol~mer particles was about 0.07 ~ The measured molecular weight of the latex was 120,000.
~ynthesis Example 2 (Aqueous dispersion containing exemplified copol~merized polymer 6) In a 1 liter four-headed flask (each head bei~g equipped with a thermometer and a reflux condenser, a 300 ml dropping funnel (A), a 300 ml dropping funnel (B) and a stirring apparatus) were placed 2 g of anionic surface active agent, Cintor~x L-100 (a trade name of ~odium lauryl~ulfate produced and sold by Nippon Yushi Co., Ltd.) and 266 g of distilled water, and thereinto was intro~uce~ nitrogen gas for 30 minutes, followed by elevatin~ the in~ide temperature of the flask to 80C~ Subsequently, to the flask were simultaneously added dropwise over 30 minutes a mixture of 16901 g of n-butyl acrylate a~d 8.8 g of 2-acetoacetoxyethyl - 37 ~

5~

acrylate throu~h the fun~el (A) and 200 ml of an aqueous solution of 22.1 g of sodium 1-sulfopropyl-3 acrylamide through the funnel (B). A~ter completio~ of the dropwise addition~
stirring of the flask was conti~ued for 1 hour, and the inside temperature was allowed to fall to room temperature to terminate the reaction. A concentration of polymer material i~ the aqueous polymer la-tex thu~ obtained was 30% by weight and a particle diameter of the dispersed polymer particles was about 0.09 ~. The measured molecular weight of the polymer was 68,000.
Synthesis Example 3 (Aqueous dispersion contai~i~g exemplified copolymerized polymer 14) In a 2-liter four headed flask (each head bei~g equipped with a thermometer, a reflux co~de~ser, a 300 ml dropping funnel and a stirrin~ apparatus) wære placed 10 g of anionic surface active agent, Cintorex ~-100 (a trade name of sodium laurylsulfate produced and sold by ~ippon Yushi Co~, Ltd.~ and 600 g of distilled water~ a~d thereinto was i~troduced nitro~e~ gas for 30 minutes,followed by elevating the inside temperature of the flask to 85C~, and thereinto was introduced nitrogen gas for 30 minutes, followed ~y elevating the inside temperature of the flask to 85C.
Subsequently, to the flask were added 0.5 g of potassium - 3~ -persulfate, 0.2 g of sodium bisulfite and 0~5 g of p-toluenesulfonic acid and, immediately thereafter was added dropwise over 30 minutes a mixture of 160 g of isobutyl acrylate and 40 g of glycidyl acrylate through the dropping funnel. After completion of the dropwiRe addition, stirring of the contents of the flask was continued for 15 hours.
Subsequently, the i~side temperature of ~he flask was allowed to fall down to room temperature to terminate the reaction.
A concentration of polymer material in the aqueous polymer latex thus obtained was 20% by weight, ~d a particl~ diameter of the dispersed polymer particles was about 0.l ~. As the result of N~ and elementary analysis, the polymer present in the latex was confirmed to be the exemplified copolymerized polymer 14, and the measured molecular weight of the polymer was 140,000.
~ynthesis Example 4 (Aqueous dispersion containing exemplified copolymerized polymer 15) In a 2-liter four headed flask (each head belng equipped with a thermometer and a reflux condensert a 300 ml dropping funnel (A), a 200 ml dropping funnel (B) and a stirring apparatus) were added 2 g of sodium triisopropyl napthalene sulfonate, ~n anio~ic surface active agent, and 200 g of distilled water, and thereinto was introduced nitrogen .

:~45~

gas for 30 minutes, followed by elevating the inside temperature of the flask to 75C. Subsequently, to the flask were added 0.5 g of ammonium persulfate and 0.1 g of sodium acid sulfite and, immediately thereafter were simultaneously added dropwise over ~0 minutes 173.5 ~ of methyl acrylate through the ~unnel (A) and 100 ml of an aqueous solution comprising 26.5 g of sodium 3-acroyloxypheny1-1-sulfonate and 0.2 g of sodium bisulfite. After completion of the dropwise addition, stirring of the contents of the ~lask was continued. Subsequently, the inside temperature was allowed to fall down to room tem~erature to terminate the reaction~ A concentration of polymer material in the aqueous polymer latex thus obtained was 40% by weight~
and a particle diameter of the dispersed polymer particles wa~
about 0.08 ~. The molecular weight o~ the polymer was 84,000.
Synthesis Example 5 (Aqueous disper~io~ containing exemplified copolymerized polymer 20) In a 2 liter four-headed flask (each head being equipped with a thermometex and a reflux condenser, a 300 ml dropping ~unnel (A), a 300 ml dropping funnel (B) and a stirring apparatus) were placed 1 g of an anionic surface active agent, Newrex R (a trade name of ~odium dodec~lbenzenesulfonate produced and sold by Nissan Kagaku Co., ~td.) and 271 ~ of distilled water, and thereinto was introduced nitro~en ga~ for _ 40 -8~

30 minutes, followed by elevating the inside temperature of the flask to 80C. Subsequently, to the flask was added 0.5 g of azobiscyanovaleric acid and, immediately thereafter were simultaneously added dropwise over 30 minutes 159 g oP ethyl acrylate througn the funnel (A) and 100 ml of an aqueous solution of 41 g of sodium 3-acroyloxypropane-2-hydroxy-1 sulfonate through the funnel (B). After completion of the dropwise addition, stirring of the content~ of the fla~k was continued for 1 hour. Subsequently~ the inside temperature was allowed to fall do~ to room temperature to terminate the reaction. A concentration of polymer material in the aqueous polymer latex thus obtained was 35% by weight, a~d a particle diameter of the dispersed polymer particles was a~out 0.09 ~.
~he molecular weight of the polymer as measured was 117,000.
Synthesis Example 6 (Aqueous dispersion containing exemplified copolymerized polymer 2) In a 3-liter four-headed flask (each head being equipped with a thermometer and a reflux conden~er, two pieces of a 30~ ml droppi~g funnel and a stirring apparatus were placed 2 g of an ~nionic surface actiYe agent, Newrex R ~sodium dodecylbenzenesulfonate produced a~d sold by Nissan Kagaku Co., Ltd.) and 1.2 liters of distilled wat~r, and the inside temperature of the flask wa~ ele~ated to 85C. while introducing _ 41 -~51~

thereinto nitrogen gas for 30 mi~utes. Subsequently, to the flask were added 2 g of potassium persulfate and 0.4 g of sodium acid sulfite and, 5 minutes thereafter were simulta~eously added dropwise over ~0 minutes while introducing thereln nitrogen gas 490 g of isobutyl acrylate and a solution of a mixture of 40.6 g of Y-sulfoethyl acrylate sodium salt and 0.6 g of ~odium acid sulfite in 400 ml of pure water. Thereafter, ~tirring of the contents of the flask wa~ continued for 4 hours while maintain-ing the inside temperature at 85C. Subsequently, the temper-ature was allowed to fall down to room temperature to terminate the reaction~ A concentration of polymer material in the aqueous polymer latex thus obtained was 25.3% by weight, and a particle diameter of the dispersed polymer particles was 0.07~-The molecular weight of the polymer as measured was 105,0000 Following the procedures of the synthesis examples mentioned above, aqueous polymer latexes co~taini~g copolymerized polymers previously exemplified can readily be ~ynthesized.
Polymer latex compositions loaded with photo-~raphic hydrophobic additives are applicable to every ob~ect to which polymer latex compositions obtained according to the known processes can be applied~
~ he polymer latex composition loaded with a photo-graphic hydrophobic additive can be coated on a photographic support to form a layer with or without a photographic binder.

~ 4~ -The photographic material contains at least one photosen~itive layer. ~he layer containing the polymer latex composition may be a photo~ensitive layer or such a non-photosensitive layer as a protective or intermediate layer. ~ preferable ex~mple of the photosensitive layer is a silver halide photosen~itive layer.
In accordance with the proces8 o~ th~ pre~ent invention, there can be accomplished the object of the invention mentioned previously and, moreo~er, because of excellent uniformity in particle diameter of the di~per~ed polymer particle~ i~p.regnated according to the present process with hydrophobic materials present in an aqueou~ polymer latexes, in the case of color photographic materials containing couplers to which the present process has been applied, chromoge~ic characteristics at the time of color development are excellent as compared with those of color photographic material~ obtained according to the prior art processes and further the color images obtained are found favorable in color purity as well as in stability.
~ urther, i~ accordance with the present inventio~
there c~n be enlarged tha selection range of polymers, when compared with the prior art processes, with the result that the dispersed polymer particles present in t~e present polymer latex composition can be i.mpregnated with such materials which - 4~ ~

~5~

have heretofore been believed to be unusable for loading purposes and thus the practical range of impre~nable materials has now been successfully broadenedO
The present inve~tion is illustrated below with reference to examples~ while showing various modifications of the mixing order of water (i.e. a dispersion medium for a~
aqueous polymer latex), water-miscible orga~ic ~olvents, water-i~iscible organic solvent and hydrophobic materials~
It should be conqtrued, however, that embodiments of the present invention are not limited to thess examples.
~xample 1 Using an aqueou~ polymer latex comprising exemplified copolymeri~ed polymer 2 (polymer material concentration 5%), t~lere were prepared impregna~ed polymer la~ex composition according to the following five modes of the mixing order.
a) Into a mixture comprising 100 ml of the aqueous polymer latex, 150 ml of a water miscible organic solvent of tetrahydro~uran (hereinafter called ~HF) : acetone = 1 : 1 and 20 ml of ethyl acetate as a water immiscible organic solvent was incorporated 10 ~ of 2-octafluoropentyl~mido-5-~2-(2,4-di-tert-amylphenoxy)hexylamido~phe~ol as a cyan coupler, and the resulting mixture was stirred, whereupon all of the coupler was loaded in dispersed pol~mer particles to yield a uniform dispersion in 1 to 2 minute~. Using a rotary evaporator, the 1145~81 organic ~olvents were removed from the liquid under reduced pressure according to the usual procedure. ~he composition thus obtained was added to 100 ml of a 6% gelatin solution to obtain a dispersion a).
b) Into a mixture comprising 100 ml of the aforesaid aqueous polymer latex and 150 ml of the aforesaid aceton solvent mixture was added 10 g of the aforesaid cyan coupler.
While stirring the ~uspension was incorporated with 20 ml of ethyl acetate and the stirring was further continued, whereupon the coupler was all loaded in dispersed polymer particles to yield a uniform dispersio~ in 1 to 2 minutes. The organic solvent was removed in the same manner as above, and the resulting composition was incorporated with 100 ml of a 6%
gelatin solution to obtain a dispersion b).
c) A mixture comprising 10 g of the afore~aid coupler and 100 ml of the aforesaid aqueous polymer latex was incorporated with stirring with 150 ml of the aforesaid THF
acetone solve~t mixture and further with 20 ml of ethyl acetate, whereupon the coupler was all loaded in dispersed polymer particles to yield a uniform dispersion in 1 to 2 minutes. In the same manner as above, the organic solvent was removed, and the resulting composition wa~ incorporated with 100 ml of a 6%
gelatin solution to obtain a dispersio~ c).
d) In a mixture comprising 150 ml of the aforesaid THF

~5~

acetone solvent and 20 ml of ethyl acetate was previously dissolved 10 g of the aforesaid coupler. This coupler solution was incorporated with stirring over 2 minutes with 100 ml of the aforesaid aqueous polymer latex. In the same manner as above, the organic solvent was removedg and the re~ulting composition was incorporated with 100 ml of a 6% gelatin solution to obtai~ a dispersion d).
e) A solution o~ 10 g of the aforesaid coupler in 150 ml of the aforesaid ~F acetone solvent mixture wa~ incorporatad with stirring over 2 minutes with 100 ml of the aforesaid aqueous polymer latex~ Although parts of the coupler were deposited, when 20 ml of ethyl acetate was added thereto, where-upon the coupler was all loaded in di~persed polymer particles to yield a uniform di~persion in a short time. In the same ma~ner as above, the organic solvent was removed, and the resulting composition was incorporated with 100 ml of a 6%
gelatin solution to obtain a dispersion e).
For comparisont the s~me procedures as in a) through e) were repeated~ except that the ethyl acet~te was not u~ed, to prepare fiYe kinds of dispersions f) through j). Under optical microscopic observation of the state of dispersion, the dispersions A) through e) were all fou~d favorable a~d no precipitates were found at all, whereas the dispersions f) through j) all involved therein deposition of the coupler and ~5~

tha state of dispersion thereof was found poor. In the manner explained above, it is understood that in accorance with the present invention there are obtained favorable di~persion irrespective of the mixing order and~ moreover, the use of a water immiscible organic solvent i~ quite effective.
Example 2 An aqueous polymer latex (polymer material concen-tration 10%) containing exemplified copolymerized pol~mer ~3 was incorporated in a m~nner mentioned below with an organic solvent to prepare mixture A and B.
A Aqueous polymer latex 50 ml ~H~ : acetone = 1 : 1 75 ml 5thyl acetate 10 ml B Aqueous polymer latex 50 ml ~H~ : acetone = 1 : 1 75 ml Each of the mixtures thus obtained was incorporated while stirring with 2-(a-(2,4-di-tert-amylphenoxy~butylylamido~-4,6-dichloro-5-methylphe~ol as a cyan coupler in varying amounts as shown in the following table. Usi~g a rotary evaporator, the organic solvents were removed under reduced pressure according to a usual way, and the resulting composition was incorporated with 100 ml of a 10% gelatin solution to prepare a dispersion. ~he dispersions obtained in the above manner were subjected to microscopic observation to investigate - 1~7 -.

~5~8~

the presence therein of precipitates and aggregates to obtain the following results~
TABLE
Mixture Amount of coupler ~ B
5 g Good Good 1) 10 g Good Poor 12.5 g Good Precipitates were formed on removal of solvent 15 g Good Precipitates were formed on removal of solvent 20 g Slightly Precipitates were poor formed on removal of solvent he expression~ "Good", "Poor" and "Slightly poor" in the a~ove table were individuall~ determined on thebasis of the results of observation to have the following mea~ings.
"Good" : No precipitate and no aggrega~es are observed at all.
"~lightly poor" : Precipitates and aggregates are slightly observed~
"Poor" : Considerable precipitates and aggregates are observed.

_ 48 -38~

As is clear from the above results, in accordance with the process of the present invention, the polymer dispersion particles can be impregnated with the coupler up to three times of` the polymer dispersion particles by weight, whereas in the absence of the water-immiscible organic solvent it was a limit to impregnate the polymer dispersion particles with the coupler in an amount equal to that of the polymer dispersion particles ~xample 3 1) Into a mixture comprising 100 ml of an aqueous polymer latex (polymer matsrial concentration 15%), 150 ml of a solvent mixture of THF : acetone = 1 : 1 and 20 ml of ethyl acetate was incorporated with 30 g of a yellow coupler with stirring, -(3-benzyl-2,4-dioxoimidazolidine-3-yl)-~-pivaloyl-5-a'-(2,4-di-tert-amylphenoxy)butylylamido-2-chloro-acetanilide.
In about 1 minute after the addition, the coupler particles were completely loaded in dispersed polymer particles to yield a uniform dispersion. Using a rotary evaporator, the solvents were removed from the liquid under reduced pressure according to a usual procedure, and the resulting composition was incorporated with 100 ml of a 10% gelatin solution to obtain a uniform dispersion B.
2) In a mixture comprising 150 ml of the a~oresaid THF
acetone solvent mixture and 20 ml of ethyl acetate was dissolved ~s~

30 g of the aforesaid yellow couplerO The resulting coupler solution was incorporated with stirring over 2 minutes with 100 ml of the aforesaid aqueous polymer latex. The solvents were removed by usinæ a rotary evaporator~ and the resulting composition was incorporated with 100 ml of a 10% gelatin solution to obtain a uniform dispersion C.
3) ~he same procedures as in the preceding 1) and 2) were repeated, except that the use of the ethyl acetate was omitted, to ~ind that no complete impregnation of the coupler was observed and considerable amounts ~f precipitates were observed.
~xample 4 20 Grams of the yellow coupler used in Example 3 was dissolved in a mixture comprising 10 g of dibutyl phthalate and 50 ml o~ ethyl acetate. ~he resulting solution was incorporated into 200 ml of a 5% gelatin solution containi~g Alkanol XC (a trade name of alkylbenzenesulfonic acid produced and sold by DU Pont Co.), and the resulting mixture was dispersed with a colloid mill to obtain a disper~ion A. ~his dispersiou and the dispersions obtained in ~xample 3 were individually mixed ~ith a silver bromide emul~ion for color paper, and the resulting mixtures were individually coated on a cellulose triacetate film base in a manner as shown in the following table to prepare samples.

~ABLE
Amount of Amou~t of emulsion ~ample No.DlsperSl~ coupler converted intQ
~mg/dm2) silver (m~/dm~) 1 (comparative) A 9.3 6.2 2 B 8.9 5.9 3 C 902 6.1 After imagewise exposure, these samples were developed at 31C. and for 3 minutes and 30 seconds with a developer having the under-mentioned composition, a~d then subjected according to the usual procedure to bleach-fixing, water-washing and drying.
Composition of the developer:
2-Methy1-4-(N-ethyl-N-~
methanesulfonamidoethylamino)aniline 1.5 sul~ate 4.5 g Sodium carbonate monohydrate 20 g Potassium bromide 2.0 g ~odium sulfite 3.0 g ~Iydroxylamine sulfate 2.0 K
Sodium hexametaphosphate 2~0 g Benzyl alcohol 10 ml Water to make 1 liter a~d adjust to pH 10.1.
'rhe samples thus processed were subjected to sensitometry to obtain results as show~ in the following ~5~8~

table, in which the speed was represented by a relative value as measure by assuming the speed of sample 1 as 100 (dispersed according to the loading process using dibutyl phthalate).
~ABLE
Sample No. Speed D min ~ D max 1 100 0.08 2018 1.95 103 0.06 2.32 2.10 105 0~07 2.29 2.18 ~ s is clear from the above table 7 the samples of the present invention where no colloid mill was used ~or disper~ion purposes were free from deterioratio~ of the coupler and were superior in every photographic property to the comparative sample 1.
Example 5 Into a mixture comprising 100 ml o~ an aqueous polymer iatex (polymer material concentration 15%), 160 ml of acetone and 40 mi o~ ethyl acetate was incorporated with 30 g of a magenta coupler with stirring, 1-~2,4~6-trichlorophenyl-3-(2-chloro-5-octadccylsuccinimidoanilino)-pyrazolino-5-o~e.
The stirring was continued, whereupon the coupler was loaded in dispersed polymer particle~ to yield a homogeneous liquid in 1 to 2 ~inutes. A~ter havin~ removed the organic solvents from the liquid under reduced pressure, the resulting composition was incorporated with 100 ml of a 10% gelatin solution to obtain a uniform dispersion D.
For comparison purposes 9 a solution of 20 g of the aforesaid magenta coupler in a mixture of 10 g of dibutyl phthalate and 60 ml of ethyl acetate was incorporated into 200 ml of a 5h gelatin solution containing as a dispersing agent, Alkanol XC (a trade name o~ the a~oresaid product), and the resulting mixture was dispersed with a colloid mill to obtain a disper~ion E.
~ he two dispersion thus obtained were individually incorporated into a silver chlorobromide emulsion for color paper, and the emulsions were individually coated on a cellulose triac~tate film base to prepare sample~ in the manner as shown in the following table.
TABI~
~iample No. Dispersio~ Amount of ~mouIl~ of emulsio~
couple~ con~erted into silver (mg/d:m~) (mg/d~2) 1 D 5.7 4,4 2 E 6.5 5.0 After wedgewise exposure, these samples were individually processed in the same manner as in Example 4 to obtain the following results~

5~

Sample ~o. Speed D min Y D max 1 104 0.05 2~10 2.03 2 100 0.08 2.03 1.86 As is clear from the above results, the sample 1 of the present invention was superior i~ every photographic property to t.he comparative sample 2.
Example 6 Example 1 was repeated, except that in place of the water-immiscible organic solvent, et4yl acetate, u~ed in Example 1, there were used 5 kinds of water-immiscible organic solvents, i.e. cyclohexanone, cyclohexanol, benxyl alcohol, chloroform and toluene at the time of impregnation of the coupler in accordance with the present inventio~. As the result, a uniform dispersion was obtained in each case while no p.recipitates or aggregates were not observed at all. These dispersions were individually incorporated into a photographic emulsion and measured in photographic propertieq to obtain excellents results similar to those obtained in Example 1 Example 7 Into a mixture compri~ing 100 ml of an aqueous polymer latex (polymer material concentration 10%) containing exempli~ied copolymerized polymer 28~ 150 ml of a solve~t mixture of THF : acetone = 1 : 1 ~nd 20 ml of ethyl acetate ~5~

was incorporated with 20 g of a cyan coupler with stirring, 2-(~-(2,4-di-tert-amylphenoxy)butylylamido)-4,6-dichloro-5-methylphenol, whereupon particle~ of the coupler were loaded in 1 to 2 minutes in dispersed polymer particles to yield a homogeneous liquid. Using a rotary evaporator, the organic solvents were removed from the liquid under reduced pressure and the resulting compQsition was then incorpora~ed into 100 ml of a 10% gelatin solution to obtai~ a dispersion G.
Following the above procedure, disper~ions X and I
were prepared by adding 3 g of dibutyl phthalate and 3 ~ of tricresyl phosphate, respectively, to the organic solvent mixture, prior to the addition thereto of the coupler. ~or comparison, furthermore, the cyan coupler was dissolved in a mixture of 5 g of dibutyl phthalate and 30 ml of et4yl acetate.
q`he resulting solution was mixed with 100 ml of a 5% gelatin solution containing ~lkanol XC (a trade name of the aforesaid product), dispersed with a colloid mill a~d then i~corporated with 100 ml of a 5% gelatin solu~ion to prepare a dispersion F.
After h~ving been mixed wlth a red-sensitive silver chlorobromide emulsion for color paper, these dispersions thus obtained were individually coated Oil a cellulose triacetate film base in the following manner to prepare sample~O

~s~

Sample No. Dispersion Amount of Amount of emulsion coupler 2 converted into 2 (mg/dm ) silver (mg/dm ) 1 ~ 8.1 4.5 (Comparative) 2 G 7.8 4~3 3 H 7.6 4.2 4 I 7.8 4.3 After wedgewise exposure, the thus prepared samples were individually developed at ~1C, for 4 minutes with a developer having the following compositio~, followed by blech-fixing, water-washing and drying according to the usual procedure.
2-Amino-5-(N,~-diethylamino)toluene292 g ~ydroxyla~ne sulfate 3.0 g Sodium carbonate monohydrate 31.2 g Sodium sulfite 1~5 g Potas~ium bromide 0.6 Water to make 1 liter and ad just to pH 10.3.
~he sensitometrical refiults obtained on the thus processed samples were as show~ in the following table.

~s~

TAB~E
Sample ~o. Speed D mi~ Y D max 1 100 0.14 2.48 1.88 (Comparative) 2 110 0~11 2~58 2aO1 3 108 0~13 2~57 2~08 4 101 0~13 2.65 2~11 From the above-mentioned results~ it i8 underBtood that as compared with the prior art processes~ excellent photographic characteristics are obtained accordin~ to the process of the present invention, and that the use of high boiling organic solvents is po~sible in the preparation of the coupler-impre~nated aqueous polymer latexe~.
Example 8 In a mixture comprisin~ 10 g of dibutyl phthalate and 50 ml of ethyl acetate wa~ dissolved 10 g o~ an ultraviolet ab~orber, 2-(2'-hydroxy-5'-tert-butylphenyl)benztriazole. The resulting solution was mixed with 250 ml of a 10% gelatin solution containing as a dispersing agent Alkanol XC ~a trade name of the aforesaid product), and the mixture was treated with a colloid mill to prepare a dispersionD Usin~ a rotary evaporator, the organic solvents were removed from the dispersion under reduced pressure to prepare a dispersion J~
~ubsequently, into the mixture used in Example 7 compri~ing 5~

100 ml of the aqueous polymer latex, 150 ml of the solvent mixture of THF : acetone = 1 ; 1 and 20 ml of ethyl acetate was incorporated with stirring with 10 g of the aforesaid ultraviolet absorber, whereupon the absorber was all loaded in 1 to 2 minutes in dispersed polymer particles to yield 8 uniform dispersion~ Using a rotary evaporator, the organic solvents were removed from the dispersion under reduced pressure, and the resulting composition was then incorporated into 250 ml of a 10% gelatin solution to prepare a dispersion K~ The two dispersions thus prepared were individually coated in the following manner on a cellulose triacetate film base and then dried to prepare samples. Using a spectrophotometer, the samples thus prepared were measured in optical density at 370 nm and 415 nm to obtain the results as shown in the following table.
~AB~E
Dispersion Amount of Amount of Optical density gelatin2) ab~(orb/~ ) 37 Dm 415 nm J 0~55 0.2 1.6 0.4 (Comparative) 0.55 0~2 2.9 0.10 As is clear from the above table, the sample having a dispersion of the ultraviolet absorber according to the ~5~

process of the present invention had a density at a very hi~h level in the ultraviolet region and had a low density in the visible region, showing sharp cut-off characteristios, and this showed that the ultra~iolet absorber had been dispersed extremely uniformly.
`xample 9 The same procedure as in Example 8 was repeated but usin~ a stain inhibitor, 2,5-dioctylhydroquinone, in place of the ultraviolet absorber to prepare a comparative dispersion L
~nd a dispersion M according to the present invention. The t~o dispersion thus obtained were subjected to microscopic observation in the same manner a~ in Example 2 to investigate the present therein of precipitates and ag~regates. Further after having allowed to stand for 2 hours after dispersing the stain inhibitor, each dispersion was diluted with water to 10 times by volume and then measured in densit~ using white li~ht.
'l'he results obtained were as shown in the following table.
TABLE
Dispersion Dispersibility~ Density L (Comparative) Poor 70%
M Good 4~/0 Note: ~ispersibility was determined on the same standard as in Example 2.
As is clear from the above table, the dispersion prepared according to the present process demonstrated better results.

Claims (12)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A process for incorporating a hydrophobic substance into a hydrophilic colloid solution comprising mixing a polymer particle dispersed in an aqueous polymer latex, the hydrophobic substance, a water-miscible organic solvent and a water-immiscible organic solvent whereby the polymer particle is loaded with the hydrophobic substance and incorporating the polymer particle loaded with the hydrophobic substance into the hydro-philic colloid solution.

2. A process according to claim 1, wherein the polymer particle contains at least one compound having at least one hydrophilic group selected from the group consisting of sulfo, sulfonate, sulfonyl, carboxy, carboxylate, hydroxy, amido, sulfonamido, quaternary ammonium, polyalkylene oxide and sulfate groups.

3. A process according to claim 1, in which the polymer particle contains 1 to 50% by weight of a monomer unit selected from the group consisting of carboxy, carboxylate, sulfo, sulfonate, sulfonyl and sulfate groups.

4. A process according to claim 3, in which the polymer particles contains 2 to 50% by weight of a monomer unit selected from the group consisting of carboxy, carboxylate, sulfo, sulfonate, sulfate and sulfonyl groups, and 0.2 to 10%
by weight of a monomer unit having an active methylene group.

5. A process according to claim 1, in which the polymer particles contains 10 to 70% by weight of a monomer unit having a hydroxy group.

6. A process according to claim 1, wherein a concentration of the polymer particle dispersed in an aqueous polymer latex is less than 60% by weight.

7. A process according to claim 1, wherein the hydrophobic substance is a photographic additive.

8. A process according to claim 7, wherein the photo-graphic additive is a coupler, ultraviolet absorber, development inhibitor releasing material, cross oxidation dye releasing agent or photographic dye.

9. A process according to claim 1, wherein a water-miscible organic solvent used has a miscibility of greater than 20% by weight in water, and a water-immiscible organic solvent used has a miscibility of not more than 20% by weight in water.

10. A process according to claim 1, wherein the proportion between the water-miscible organic solvent and the water-immiscible organic solvent used is within the range of 1 : 1 to 1 : 0.01.

11. A process according to claim 1, wherein the water-miscible organic solvent is selected from a group comprising of ethyl acetate, n-butyl alcohol, chloroform, ethyl chloride, ethylene chloride, dibromoethane, n-propyl acetate, n-butyl acetate, sec-butyl acetate, cyclohexanone, cyclohexanol, iso-butyl alcohol, n-amyl alcohol, iso-amyl alcohol, sec-amyl alcohol, diisopropyl ether and benzyl alcohol.

12. A photographic material containing an impregnated polymer latex composition which was prepared by a process according to claim 7.