JP2003231757A - Method for manufacturing aqueous dispersion of fine particle of thermoplastic resin and toner for electrophotography - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an aqueous dispersion of fine particles of a thermoplastic resin in which extremely little solvent is left and a toner with extremely little solvent left. <P>SOLUTION: The method for manufacturing the aqueous dispersion of the fine particles of the thermoplastic resins and a toner for electrophotography are disclosed. The method is composed of three processes; (1) the first process for swelling a thermoplastic resin (P) which are self-dispersible in water by an organic solvent (S) with a boiling point below 100°C which cannot dissolve the resin (P) but can swell the resin (P), (2) the second process for manufacturing an initial aqueous dispersed material by dispersing the swollen resin finely into an aqueous medium, and (3) the third process for dispersing the fine particles of the resin (P) into the above mentioned aqueous medium by removing the organic solvent (S) from the initial aqueous dispersed material. The toner for electrophotography comprises the fine particles of the resin (P) isolated and dried from the aqueous dispersed fine particles of the thermoplastic resin (P) manufactured by this method. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electrophotographic toner,
Thermoplastic resin fine particles used for printing materials such as inks, paints, adhesives, adhesives, fiber processing, paper / paper processing, civil engineering, etc., and thermoplastic resin fine particles obtained by this manufacturing method The present invention relates to a toner for electrophotography containing a.

[0002]

2. Description of the Related Art The methods for producing an aqueous dispersion of fine thermoplastic resin particles are roughly classified into a polymerization granulation method in which emulsion particles are formed from a polymerization monomer in a polymerization process and a dispersion granulation method in which a resin is made into fine particles. Can be mentioned.

Regarding the former polymerization and granulation method, a seed polymerization method, a dispersion polymerization method, etc. have been developed based on the emulsion polymerization technology and the suspension polymerization technology, depending on the intended particle size. Other components such as an emulsifier and a suspension stabilizer are essential for stable dispersion in the composition, and their removal is difficult.
Further, this granulation method can be applied only in the production of vinyl resin emulsion.

On the other hand, the latter dispersion granulation method has a wide range of applications in that it can be applied to not only vinyl resins but also polyaddition resins, polycondensation resins and natural resins, and spray drying method and coacervation method. A manufacturing method such as a method has been developed.

The phase inversion emulsification method is one of such dispersion granulation methods. For example, an organic phase obtained by dispersing or dissolving a hydrophobic substance in a self-water-dispersible resin dissolved in an organic solvent is water. After the phase inversion emulsification by mixing with, a method for producing a microcapsule in which the organic solvent is removed (see, for example, Patent Document 1), a colorant is dispersed in an organic solvent solution of an anionic self-water-dispersible resin, After neutralizing the resin, phase inversion emulsification in an aqueous medium, followed by removal of an organic solvent and drying (for example, see Patent Document 2), as the anionic self-water dispersible resin. A method for producing a toner using a polyester resin having a neutralized salt structure (see, for example, Patent Document 3), an organic solvent solution containing a colorant and a self-water-dispersible resin, and an aqueous medium are used in a continuous emulsification disperser. Then milk After producing a toner for electrophotography of drying and removal of organic solvents (e.g., see Patent Document 4.), And the like are known. Since the self-water-dispersible thermoplastic resin is used in these methods, the thermoplastic resin fine particle aqueous dispersion can be produced without using auxiliary materials such as an emulsifier and a suspension stabilizer.

[0006]

[Patent Document 1] Japanese Patent Application Laid-Open No. 03-221137 (Claims, pages 3 to 6)

[Patent Document 2] Japanese Unexamined Patent Publication No. 05-066600 (claims, pages 6 to 7)

[Patent Document 3] Japanese Patent Application Laid-Open No. 08-212655 (claims, pages 4 to 6)

[Patent Document 4] Japanese Unexamined Patent Publication No. 09-297431 (claims, pages 3 to 6)

As described above, the phase inversion emulsification method is a useful means applicable to various thermoplastic resins, but since it was thought in mind to prepare an organic solvent solution of a self-water-dispersible thermoplastic resin, Only a study on a combination of a self-water-dispersible thermoplastic resin and an organic solvent (good solvent) capable of dissolving the thermoplastic resin has been proposed. Therefore, it has not been applied to a combination of a self-water-dispersible thermoplastic resin and an organic solvent that does not dissolve the thermoplastic resin.

Further, since the transfer emulsification method is a combination of a self-water-dispersible thermoplastic resin and an organic solvent (good solvent) capable of dissolving the thermoplastic resin, the self-water-dispersible thermoplastic resin is dispersed in an aqueous medium. The high affinity between the self-water-dispersible thermoplastic resin and the organic solvent even after the dispersion of the organic solvent, resulting in a high concentration of the organic solvent remaining in the resin particles even after the removal step of the organic solvent. was there.

Further, an aqueous dispersion prepared by blending a neutralized acid group-containing polyester resin, a water-soluble organic compound having a boiling point of 60 to 200 ° C. and water in a specific blending ratio is also known (for example, patents See Reference 5 and Patent Reference 6.).

[0010]

[Patent Document 5] JP-A-56-088454 (second
~ Page 4, page 7)

[Patent Document 6] JP-A-56-125432 (second
~ Page 4, page 7)

In these patent documents 5 and 6, a boiling point of 60
As an organic solvent having a boiling point of 100 ° C. or higher that dissolves the polyester resin as a water-soluble organic compound having a boiling point of 200 ° C. to 200 ° C., an organic solvent having a boiling point of less than 100 ° C. that does not dissolve the polyester resin is also exemplified. There is no description or suggestion of removing the organic solvent and using the compound of the polyester resin in combination with an organic solvent which does not dissolve the polyester resin, and in the examples, a boiling point of 100 ° C. at which the polyester resin is dissolved.
After producing an aqueous dispersion using any of the organic solvents including the above organic solvents (good solvents), the aqueous dispersion is used as a coating agent without removing the organic solvent. In the aqueous dispersions obtained in these examples, even if the organic solvent is removed, the organic solvent remains in the resin particles at a high concentration.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing an aqueous dispersion of thermoplastic resin fine particles having very little residual solvent remaining in resin particles, and an electrophotographic toner having very little residual solvent. That is.

[0013]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found the following findings (a).
The present invention has been completed by finding out (d).

(A) As the organic solvent, an organic solvent (S) having a boiling point of less than 100 ° C., which does not dissolve the self-water-dispersible thermoplastic resin (P) but is capable of swelling, is used. The swollen body obtained by absorbing it in the self-water-dispersible thermoplastic resin (P) can be easily transferred and emulsified to be dispersed in the form of fine particles in an aqueous medium to form a thermoplastic resin fine particle aqueous dispersion. thing.

(B) Since the organic solvent (S) having a boiling point of less than 100 ° C. which does not dissolve the self-water-dispersible thermoplastic resin (P) is used as the organic solvent, the removal of the organic solvent in the obtained water-dispersed resin. And an aqueous dispersion of thermoplastic resin fine particles having an extremely small amount of residual organic solvent can be produced.

(C) In the method for producing an aqueous dispersion of thermoplastic resin fine particles, the self-water-dispersible thermoplastic resin (P) is used.
By using together with the colorant (C), it is possible to obtain a dispersion in which fine particles of the self-water-dispersible thermoplastic resin (P) colored with the colorant (C) are dispersed in an aqueous medium.

(D) Electrons containing very little residual solvent by containing fine particles obtained by separating fine particles of the thermoplastic resin fine particle aqueous dispersion obtained by the method for producing the thermoplastic resin fine particle aqueous dispersion and drying the same. To be able to obtain photographic toner.

That is, in the present invention, the self-water-dispersible thermoplastic resin (P) does not dissolve the self-water-dispersible thermoplastic resin (P) but is capable of swelling but having an boiling point of less than 100 ° C. S) in which a swollen body is produced by swelling, a second step in which the swollen body is dispersed in an aqueous medium in the form of fine particles to produce an initial aqueous dispersion, and from the initial aqueous dispersion, A thermoplastic resin comprising a third step of producing a dispersion in which fine particles of the self-water-dispersible thermoplastic resin (P) are dispersed in the aqueous medium by removing the organic solvent (S). The present invention provides a method for producing a fine particle aqueous dispersion.

The present invention also contains fine particles obtained by separating fine particles of the self-water-dispersible thermoplastic resin (P) from the aqueous dispersion of the thermoplastic resin fine particles obtained by the above-mentioned production method and drying. The present invention provides an electrophotographic toner characterized by the following.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.
The self-water-dispersible thermoplastic resin (P) is a thermoplastic resin dispersible in an aqueous medium or a heat that enables dispersion in an aqueous medium by neutralization without using an emulsifier, a suspension stabilizer or the like. It is a plastic resin, and may be any of vinyl resin, polyaddition resin, polycondensation resin, natural resin, etc. Among them, it is possible to dissolve the thermoplastic resin (P) at room temperature such as tetrahydrofuran or methyl ethyl ketone. After the thermoplastic resin (P) is dissolved in an organic solvent, the resulting resin solution contains an aqueous medium under stirring (in the case of a thermoplastic resin which can be dispersed in an aqueous medium by neutralization, a neutralizing agent is contained. Aqueous medium) is added dropwise to carry out phase inversion emulsification and the average particle size is 1
A thermoplastic resin capable of being dispersed in a particle size of 0 μm or less is preferable, and a thermoplastic resin capable of being dispersed in a particle size of 0.1 μm or less is particularly preferable.

Examples of such self-water-dispersible thermoplastic resins include neutralized acid group-containing thermoplastic resins such as sulfonic acid metal salts and carboxylic acid metal salts; neutralized basic group-containing thermoplastic resins. Resin: Hydrophilic segment-containing thermoplastic resin such as thermoplastic resin having a so-called nonionic structure introduced such as hydroxypolyoxyethylene; Organic group having an acid group such as carboxyl group, alkanolamine and the like, ammonia, hydroxylation A thermoplastic resin that can be anionized in an aqueous phase by adding a neutralizing agent such as an inorganic base such as sodium; an organic acid or an inorganic acid having a basic group such as an amino group or a pyridine ring. Examples thereof include thermoplastic resins that can be cationized in an aqueous phase by adding a neutralizing agent such as, and among them, a neutralized acid group-containing thermoplastic resin or acid group Preferably Yunetsu thermoplastic resin, acid group-containing thermoplastic resin since it is easily stored low hygroscopic property is particularly preferred.

As the above-mentioned neutralized acid group-containing thermoplastic resin, for example, neutralized acid group-containing polyester resin, neutralized acid group-containing polyurethane resin, neutralized acid group-containing ( (Meth) acrylic resin, neutralized acid group-containing styrene resin, neutralized acid group-containing styrene-
Examples thereof include (meth) acrylic acid ester-based copolymer resins, neutralized acid group-containing rosin-based resins, and neutralized acid group-containing petroleum resins. Among these, the neutralized acid because the resin fine particles obtained by the production method of the present invention can be used as a binder for an electrophotographic toner to obtain an electrophotographic toner having excellent fixability and high image quality. Group-containing polyester resin (PE), neutralized acid group-containing styrene-
A (meth) acrylic acid ester-based copolymer resin is preferable,
Neutralized acid group-containing polyester resin (PE) is particularly preferable. The acid value when the neutralized acid group-containing polyester resin (PE) is removed from neutralization is 1 to 1
00 is preferable and 5-40 is more preferable.

As the neutralized acid group-containing polyester resin (PE), for example, a polyester resin (PE1) obtained by using a compound having a neutralized acid group as an essential component, a carboxyl group, etc. Examples of the polyester resin (PE2) obtained by preparing a polyester resin containing the acid group of 1, which becomes a self-water-dispersible thermoplastic resin (P) by neutralization, and then neutralizing the acid group . Specific examples thereof include a neutralized carboxyl group-containing polyester resin, a neutralized sulfone group-containing polyester resin, and a neutralized phosphoric acid group-containing polyester resin. The polyester resin (PE1)
Is preferably a neutralized sulfone group-containing polyester resin, and the polyester resin (PE2) is preferably a neutralized carboxyl group-containing polyester resin.

The neutralized acid group-containing polyester resin (PE1) contains, for example, a dibasic acid or its anhydride, a dihydric alcohol and a dibasic acid having a neutralized acid group as essential components. , If necessary, trifunctional or higher polybasic acid, its anhydride, monobasic acid, trifunctional or higher alcohol,
It can be prepared by a method in which monohydric alcohol or the like is used in combination and dehydration condensation is performed at a reaction temperature of 180 to 260 ° C. while measuring an acid value under heating in a nitrogen atmosphere.

Examples of the acid group-containing thermoplastic resin include acid group-containing polyester resin, acid group-containing polyurethane resin, acid group-containing (meth) acrylic resin, acid group-containing styrene resin, acid Examples thereof include group-containing styrene- (meth) acrylic acid ester-based copolymer resins, acid group-containing rosin resins, acid group-containing petroleum resins and the like. Among these, the acid group-containing polyester-based polyester resin having excellent fixing properties and high image quality can be obtained when the resin fine particles obtained by the production method of the present invention are used as a binder of the electrophotographic toner. The resin (pe) and the acid group-containing styrene- (meth) acrylic acid ester-based copolymer resin are preferable, and the acid group-containing polyester resin (pe) is particularly preferable. The acid value of the acid group-containing polyester resin (pe) is preferably 1 to 100, more preferably 5 to 40.

The acid group-containing polyester resin (pe)
For example, a polyester resin (pe1) obtained by using a compound having an acid group such as a carboxyl group as an essential component is preferable. The polyester resin (p
Specific examples of e1) include a carboxyl group-containing polyester resin, a sulfonic acid group-containing polyester resin,
Examples thereof include a phosphoric acid group-containing polyester resin, and among them, a carboxyl group-containing polyester resin is preferable.

The above-mentioned carboxyl group-containing polyester resin is, for example, essentially a dibasic acid or its anhydride and a divalent alcohol, and if necessary, a trifunctional or higher polybasic acid, its anhydride, or a monobasic acid. , Trifunctional or higher alcohol,
A monohydric alcohol or the like may be used in a composition ratio such that a carboxyl group remains, and dehydration condensation may be performed at a reaction temperature of 180 to 260 ° C. while measuring an acid value under heating in a nitrogen atmosphere.

As an apparatus used for preparing these polyester resins (PE) and (pe), batch-type production such as a reaction vessel equipped with a nitrogen inlet, a thermometer, a stirrer, and a rectification column The apparatus can be preferably used, and an extruder equipped with a degassing port, a continuous reaction apparatus, a kneader, etc. can also be used. Further, during the dehydration condensation, the esterification reaction can be promoted by reducing the pressure of the reaction system, if necessary. Further, various catalysts may be added to accelerate the esterification reaction.

Examples of the catalyst include antimony oxide, barium oxide, zinc acetate, manganese acetate, cobalt acetate, zinc succinate, zinc borate, cadmium formate, lead monoxide, calcium silicate, dibutyltin oxide, butylhydroxytin. Oxide, tetraisopropyl titanate,
Tetrabutyl titanate, magnesium methoxide, sodium methoxide and the like can be mentioned.

Examples of the dibasic acid having a neutralized acid group include sulfoterephthalic acid, 3-sulfoisophthalic acid, 4-sulfophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, Examples thereof include sodium salts such as sulfo-p-xylylene glycol and 2-sulfo-1,4-bis (hydroxyethoxy) benzene, and metal salts such as potassium salt, calcium salt, barium salt and zinc salt.

Examples of the dibasic acid and its anhydride include:
For example, maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, oxalic acid, malonic acid, succinic acid, succinic anhydride, dodecyl succinic acid, dodecyl succinic anhydride, dodecenyl succinic acid, dodecenyl succinic anhydride, Adipic acid, azelaic acid, sebacic acid, decane-
Aliphatic dibasic acids such as 1,10-dicarboxylic acid; phthalic acid, tetrahydrophthalic acid and its anhydride, hexahydrophthalic acid and its anhydride, tetrabromophthalic acid and its anhydride, tetrachlorophthalic acid and its anhydride Compounds, het acids and their anhydrides, hymic acids and their anhydrides, aromatic or alicyclic dibasic acids such as isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid and 2,6-naphthalenedicarboxylic acid.

Examples of the divalent alcohol include ethylene glycol, 1,2-propylene glycol, 1,
4-butanediol, 1,5-pentanediol, 1,
Aliphatic diols such as 6-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol and neopentyl glycol; bisphenol A such as bisphenol A and bisphenol F Bisphenol A such as ethylene oxide adduct of bisphenol A and propylene oxide adduct of bisphenol A
Examples include alkylene oxide adducts; aralkylene glycols such as xylylene diglycol; alicyclic diols such as 1,4-cyclohexane dimethanol and hydrogenated bisphenol A.

Examples of trifunctional or higher polybasic acids and their anhydrides include trimellitic acid, trimellitic anhydride, methylcyclohexene tricarboxylic acid, methylcyclohexene tricarboxylic acid anhydride, pyromellitic acid and pyromellitic anhydride. Can be mentioned.

As the monobasic acid, for example, benzoic acid, p
Examples include -tert-butylbenzoic acid and the like.

Examples of trifunctional or higher functional alcohols include glycerin, trimethylolethane, and trimethylol.
Propane, sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol
And dipentaerythritol, 2-methylpropanetriol, 1,3,5-trihydroxybenzene and tris (2-hydroxyethyl) isocyanurate.

Examples of monohydric alcohols include higher alcohols such as stearyl alcohol.

The above-mentioned dibasic acid, its anhydride, trifunctional or higher functional basic acid, its anhydride, monobasic acid and the like may be used alone or in combination of two or more kinds. .
Also, those in which a part or all of the carboxyl group is an alkyl ester, an alkenyl ester or an aryl ester can be used.

The above-mentioned dihydric alcohols, trifunctional or higher functional alcohols, monohydric alcohols and the like may be used alone or in combination of two or more.

Further, for example, a compound having both a hydroxyl group and a carboxyl group in one molecule such as dimethylolpropionic acid, dimethylolbutanoic acid, 6-hydroxyhexanoic acid or a reactive derivative thereof can be used.

Among the above-mentioned carboxyl group-containing polyester resins, the gel content is 0.3% by weight or less because an electrophotographic toner having a high maximum temperature in the non-offset region and a good low temperature fixability can be obtained. , The weight average molecular weight (Mw) measured by GPC (gel permeation chromatography) is 3,000 to 20,000, the number average molecular weight (Mn) is 1,000 to 5,000, and the ratio (M
w / Mn) is 2 to 10, 1/2 drop temperature (T1 / 2) in the flow tester is 80 to 140 ° C, and acid value is 1 to 10
0 polyester resin (I), a gel content of 2% by weight or less, and a weight average molecular weight (Mw) measured by GPC of 20.
2,000 to 2,000,000, number average molecular weight (Mn)
Is 5,000 to 20,000, and their ratio (Mw / Mn)
Is 10 to 400, 1/2 drop temperature (T1 / 2) in the flow tester is 150 to 250 ° C, and acid value is 1 to 100
It is preferable to use a polyester resin obtained by mixing the polyester resin (II) of

The polyester resin (I) has a weight average molecular weight (Mw) of 4,000 to 10,0.
00, the number average molecular weight (Mn) is 2,000 to 4,000,
It is more preferable that the polyester resin has a ratio (Mw / Mn) of 2 to 5 and a 1/2 drop temperature (T1 / 2) in the flow tester of 80 to 120 ° C.

The polyester resin (II) has a gel content of 0.2 to 0.7% by weight and a weight average molecular weight (Mw) of 200,000 to 1,000,000.
It is more preferable that the polyester resin has a number average molecular weight (Mn) of 5,000 to 10,000, Mw / Mn of these of 20 to 200, and a 1/2 drop temperature (T1 / 2) in a flow tester. .

Further, among the above-mentioned polyester resins (II), since electrophotographic toner having a wide fixing temperature range can be obtained, it can be obtained by reacting a divalent basic acid, a divalent alcohol and a difunctional epoxy compound. A polyester resin is preferable, and a polyester resin obtained by using a raw material component having a bifunctional epoxy compound content of 0.5 to 2.5% by weight is more preferable.

Examples of the bifunctional epoxy compound include bisphenol A type epoxy resin, bisphenol F type epoxy resin, ethylene glycol diglycidyl ether, hydroquinone diglycidyl ether, neopentyl glycol diglycidyl ether, and the like.
Of these, bisphenol A type epoxy resin and bisphenol F type epoxy resin are preferable. These may be used alone or in combination.

As the above-mentioned polyester resin (II), in addition to a divalent basic acid, a divalent alcohol and a bifunctional epoxy compound, 1 to 10 parts by weight of a monoepoxy compound having an alkyl group having 4 to 28 carbon atoms is used. A polyester resin obtained by using the raw material components contained therein is particularly preferable. As the monoepoxy compound having an alkyl group having 4 to 28 carbon atoms, glycidyl ester of carboxylic acid is preferable, and neodecanoic acid glycidyl ester is particularly preferable.

In the present invention, the gel content is the weight ratio of the insoluble matter when each of the polyester resin (I) and the polyester resin (II) is dissolved in tetrahydrofuran at 25 ° C. for 24 hours. In the measurement, 250 ml of tetrahydrofuran was placed in a 300 ml glass container, 1.5 g of finely crushed polyester resin was placed in a 500-mesh wire mesh bag (3 × 5 cm) and dissolved at room temperature for 24 hours. Find the percentage.

The weight average molecular weight (Mw) and the number average molecular weight (Mn) of the polyester resin in the present invention are values measured by the GPC method under the conditions shown below for the components dissolved in tetrahydrofuran. GPC device: Tosoh Corp. HLC-8120 GPC COLUMN: Tosoh Corp. TSK-GEL G-5000HXL G-4000HXL G-3000HXL G-2000HXL Solvent: Tetrahydrofuran solvent concentration: 0.5 wt% Flow rate: 1. 0 ml / min

1/2 in the flow tester according to the present invention
Falling temperature (T1 / 2) means high-performance flow tester CFT
-500 (Shimadzu), load 10kg / c
m ² , nozzle diameter 1 mm, nozzle length 1 mm, preheating at 70 ° C. for 5 minutes, heating rate at 6 ° C./min, sample amount was recorded as 1.5 g, flow tester plunger drop amount − When the height of the S-shaped curve in the temperature curve (softening flow curve) is h, it means the temperature corresponding to the height of h / 2.

The weight ratio [(I) / (II)] of the polyester resin (I) and the polyester resin (II) is as follows: fixability, anti-offset property (property that toner does not fuse to the fixing roll), and storage stability. The range of 30/70 to 70/30 is preferable because an excellent electrophotographic toner can be obtained.

The polyester resin obtained by mixing the polyester resin (I) and the polyester resin (II) has a high upper limit temperature in the non-offset region, and an electrophotographic toner having good low-temperature fixability can be obtained. Also, it can be preferably used as a raw material of an electrophotographic toner by a pulverization method. However, when used as a raw material for an electrophotographic toner by a pulverization method, neither the polyester resin (I) nor the polyester resin (II) contains an acid group such as a carboxyl group necessary for forming an aqueous dispersion. It may be one.

Further, as the carboxyl group-containing polyester resin, fine particles of the self-water-dispersible thermoplastic resin (P) can exist more stably in an aqueous medium.
A polyester resin containing an alkyl group and / or an alkenyl group is more preferable. Among them, the terminal hydroxyl group of the polyester resin having a hydroxyl group at the terminal,
Alkyl group having 4 to 20 carbon atoms or 4 to 20 carbon atoms
A polyester resin having a terminal structure produced by ring-opening addition of an acid anhydride having 20 alkenyl groups, an alkyl group having 4 to 20 carbon atoms or the number of carbon atoms in the terminal carboxyl group of the polyester resin having a carboxyl group at the terminal A polyester resin having a terminal structure formed by ring-opening addition of an aliphatic monoepoxy compound having 4 to 20 alkenyl groups is particularly preferable.

Examples of the acid anhydride having an alkyl group having 4 to 20 carbon atoms or an alkenyl group having 4 to 20 carbon atoms include, for example, n-octyl succinic anhydride, isooctyl succinic anhydride, and n-dodecenyl succinic anhydride. Examples thereof include acid and isododecenyl succinic anhydride. Among them, isododecyl succinic anhydride and dodecenyl succinic anhydride are preferable.

The aliphatic monoepoxy compound having an alkyl group having 4 to 20 carbon atoms or an alkenyl group having 4 to 20 carbon atoms is, for example, a carder, which is a glycidyl ester of a branched fatty acid manufactured by Shell Chemical Co.
E10; monoglycidyl ester of fatty acid such as castor oil fatty acid, coconut oil fatty acid, soybean oil fatty acid, tung oil fatty acid;
Examples thereof include monoglycidyl esters of branched fatty acids such as isononanoic acid.

The organic solvent (S) used in the present invention does not dissolve the self-water-dispersible thermoplastic resin (P) but has a boiling point capable of swelling [a boiling point at atmospheric pressure (101.3 KPa)]. The same applies below. ] Any organic solvent having a temperature of less than 100 ° C. may be used. When an organic solvent that dissolves the self-water-dispersible thermoplastic resin (P) and / or an organic solvent having a boiling point of 100 ° C. or higher is used, it becomes difficult to remove the organic solvent in the third step, and the self-water dispersion When an organic solvent that cannot swell the water-soluble thermoplastic resin (P) is used, it becomes difficult to disperse the self-water-dispersible thermoplastic resin (P) in the aqueous medium in the second step. Is also not preferable.

The organic solvent (S) that does not dissolve the self-water-dispersible thermoplastic resin (P) used in the present invention means that the organic solvent and the self-water-dispersible thermoplastic resin (P) are used in combination. Means an organic solvent in which the solubility of the self-water-dispersible thermoplastic resin (P) in the organic solvent at 25 ° C. is 15% by weight or less, and the self-water-dispersible thermoplastic resin (P)
It does not mean an organic solvent having a solubility of 0% by weight in the organic solvent.

In the present invention, the determination as to whether or not the organic solvent corresponds to the organic solvent (S) which does not dissolve the self-water-dispersible thermoplastic resin (P) can be made by, for example, ASTM D3132-
7.2 (Reapproved 1996) 7.2 Result Judgment (Interp
7.2.1.1.1-7.2 of retation of Results :).
It can be performed using the determination method described in 1.3.

To determine whether or not the organic solvent (S) is applicable, specifically, 15 parts by weight of the particulate self-water-dispersible thermoplastic resin (P) and 85 parts by weight of the organic solvent are placed in a flask and sealed. The dissolved state after shaking at 25 ° C. for 16 hours was observed, and the above-mentioned ASTM D3132-84 7.2.
In the following judgment classification described in 1.1 to 7.2.1.3,
1. "Complete solution" or 2. "Borderline solution" or 3.
This can be done by determining which category of "insoluble" it belongs to. 1. “Complete Solution”; a single clear phase (A single, free of clear solids or gel particles)
clear liquid phase with no distinct solid orgel pa
rticle). 2. "Borderline Solution"; a clear or turbid phase (Cloudy or
turbid but without distinct phase separation). 3. "Insoluble"; Separation into two phases: Liquid containing separated gel solid phase or liquid separated into two phases (Two ph
ases: either a liquid with separate gel solid pha
se or two separate liquids). In the present invention, as the particulate self-water-dispersible thermoplastic resin (P), a coarsely pulverized product of the self-water-dispersible thermoplastic resin (P) passed through a screen having a hole diameter of 3 mm was used for the determination.

The production method of the present invention comprises: 1. determining whether the self-water-dispersible thermoplastic resin (P) and the organic solvent (S) correspond to the organic solvent (S). "Borderline solution", or 3. This method is used in a combination of "insoluble", and by using the self-water-dispersible thermoplastic resin (P) and the organic solvent (S) in this combination,
Desolvation can be easily performed in the process.

As the organic solvent (S) used in the present invention,
Among them, since the solvent removal in the third step can be performed more easily, it is an organic solvent whose solubility in the organic solvent of the self-water-dispersible thermoplastic resin (P) at 25 ° C. is 10% by weight or less. It is more preferable that the organic solvent is 7% by weight or less. At this time, the solubility is determined by determining whether the organic solvent corresponds to the organic solvent (S) with the resin concentration of 15% by weight, instead of the resin concentration of 10% by weight.
Alternatively, it is possible to make the determination at 7% by weight.

Further, as the organic solvent (S), it is easy to remove it from the particulate swollen body dispersed in the aqueous medium, and the resin particles having a very small residual solvent can be easily and efficiently produced economically. Therefore, the organic solvent (S1) compatible with water is preferable. However, as the organic solvent (S1), it is not necessary that water and the organic solvent form a uniform phase at all mixing ratios, and the self-water-dispersible thermoplastic resin (P) is swollen with the organic solvent (S). It is sufficient that the resulting swollen body is compatible with each other in the temperature at which the swelled body is dispersed in the aqueous medium and the composition range of water and the organic solvent. The organic solvent (S1) is
Either a single solvent or a mixed solvent may be used as long as this condition is satisfied, but a solvent that is compatible with water at the temperature when the organic solvent (S1) is removed in the third step is preferable, and at 25 ° C. Those which are compatible with water are more preferable. Among them, the organic solvent (S1) preferably has a solubility in water at 25 ° C of 50% by weight or more, and is particularly preferably compatible with water in all proportions at 25 ° C. Furthermore, when the organic solvent (S1) is a mixed solvent, the boiling points of the organic solvents used are preferably less than 100 ° C. Further, the boiling point of the organic solvent (S1) is more preferably 40 to 90 ° C. More preferably 40 to 85 ° C, most preferably 40 to 60 ° C.
Is.

Examples of the organic solvent (S1) include:
Acetone (Solubility: Compatible with water in all proportions. Boiling point:
Ketones such as 56.1 ° C; methanol (solubility: compatible with water in all proportions, boiling point: 64.7 ° C), ethanol (solubility: compatible with water in all proportions, boiling point: 78.
Alcohols such as isopropyl alcohol (solubility: water-miscible in all proportions, boiling point: 82.26 ° C.); methyl acetate (solubility: 24% by weight, boiling point: 56.9)
C.) and the like. These organic solvents (S1) may be used alone or as a mixed solvent in which two or more kinds are mixed. Preferred organic solvents (S1) are ketones and alcohols, more preferred are acetone and isopropyl alcohol, and most preferred are acetone.

The amount of the organic solvent (S) used depends on the particle size of the resin fine particles in the desired aqueous dispersion of the thermoplastic resin fine particles, but in the first step, the self-water-dispersible thermoplastic resin (P) is used. ) Fully absorbs the organic solvent (S), swells, and is easily dispersed in the form of fine particles (paste)
Of the swelled body, the dispersion of the swelled body in the aqueous medium in the second step is easy, the amount of the aqueous medium used to complete the dispersion can be suppressed,
Since the content of the organic solvent in the thermoplastic resin fine particle aqueous dispersion does not increase and the production efficiency becomes good, it is 5 to 100 parts by weight of the self-water-dispersible thermoplastic resin (P).
300 weight part is preferable, More preferably, it is 10-200.
Parts by weight, most preferably 20 to 150 parts by weight.

The amount of water used is preferably 70 to 400 parts by weight, more preferably 100 to 250 parts by weight, based on 100 parts by weight of the total of the self-water-dispersible thermoplastic resin (P) and the organic solvent (S). preferable.

The aqueous medium used in the present invention is, for example, a self-water-dispersible thermoplastic resin (P), an emulsifier,
Water is preferred when using a thermoplastic resin that can be dispersed in an aqueous medium without using a suspension stabilizer or the like, and,
If the self-water-dispersible thermoplastic resin (P) is a thermoplastic resin that can be dispersed in an aqueous medium by neutralization without using an emulsifier, a suspension stabilizer, etc., a neutralizing agent should be contained. Water is preferred. Incidentally, these aqueous media,
If necessary, an emulsifier, a suspension stabilizer and the like can be further contained, but it is usually preferable not to contain them.

In the production method of the present invention, when the self-water-dispersible thermoplastic resin (P) is a thermoplastic resin that can be dispersed in an aqueous medium by neutralization, the self-water-dispersible thermoplastic resin is used. In order to impart dispersibility, neutralization is performed with a neutralizing agent in any step up to the second step of dispersing the swollen body obtained by swelling the thermoplastic resin with an organic solvent (S) in an aqueous medium. However, above all, it is preferable to neutralize the swollen body with an aqueous medium containing a neutralizing agent in the second step of dispersing the swollen body in the aqueous medium.

When the thermoplastic resin capable of being dispersed in an aqueous medium by the neutralization is an acid group-containing thermoplastic resin, the neutralizing agent used for neutralizing the acid group is, for example, sodium hydroxide, Alkali compounds such as potassium hydroxide and lithium hydroxide; carbonates of alkali metals such as sodium, potassium and lithium; acetates of the above alkali metals; ammonia water; methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, etc. Alkyl amines; alkanol amines such as diethanol amine and the like. Of these, ammonia water is preferred.

Further, when the thermoplastic resin which can be dispersed in an aqueous medium by the neutralization is a basic group-containing thermoplastic resin, the neutralizing agent used for neutralizing the basic group is:
For example, organic acids such as formic acid, acetic acid, and propionic acid; hydrochloric acid,
Examples thereof include inorganic acids such as sulfuric acid, nitric acid, phosphoric acid and the like.

The amount of the neutralizing agent to be used is 0.9 to, respectively, with respect to the equivalent amount of the acid group in the acid group-containing thermoplastic resin or the equivalent amount of the basic group in the basic group-containing thermoplastic resin. 5.
The amount is preferably 0 times equivalent, and 1.0 to 3.
It is more preferable that the amount is 0 times equivalent.

The method for producing the swollen body in the first step of the production method of the present invention is not particularly limited, but the swollen body can be obtained in a short time, and then the aqueous medium of the swollen body in the second step. It is preferable to produce the swollen body by using the particulate self-water-dispersible thermoplastic resin (P) and heating it together with the organic solvent (S), because the dispersion in the inside becomes easy. More preferably, the swollen body is produced under pressure. At this time, the heating temperature of the self-water-dispersible thermoplastic resin (P) and the organic solvent (S) is preferably the boiling point of the organic solvent (S) or higher, and the boiling point of the organic solvent (S) to 180 ° C. Is more preferable, and the boiling point of the organic solvent (S) + 10 ° C. to 120 ° C. is particularly preferable. The pressure applied in this system is preferably 0.1 to 2.0 MPa in gauge pressure, more preferably 0.2 to 1.5 MPa in gauge pressure, and further preferably 0.3 to 1 in gauge pressure. It is 0.0 MPa. As a method of pressurizing the system, for example, a method of vaporizing the organic solvent (S) by heating to obtain the swollen body and pressurizing the system, or introducing an inert gas into the system in advance and preliminarily applying After pressing
Examples of the method include heating and further pressurizing by vaporizing the organic solvent (S). However, the reflux and boiling of the organic solvent (S) can be suppressed, and an aqueous dispersion of thermoplastic resin fine particles having a narrow particle size distribution can be obtained. Therefore, the method of pre-pressurizing is preferable. The prepressurization is preferably 0.05 to 0.5 MPa.

As a method for producing an initial aqueous dispersion by dispersing the swollen body obtained in the second step in the form of fine particles after obtaining the swollen body in the first step,
Although not particularly limited, the swollen body obtained by heating to a temperature not lower than the boiling point of the organic solvent (S) in the first step under pressure because the swollen body can be easily dispersed in the aqueous medium. It is preferable to use the above method to disperse the swollen body into fine particles in the aqueous medium under pressure at a temperature not lower than the boiling point of the organic solvent (S) and not higher than 120 ° C. in the aqueous medium to obtain an initial aqueous dispersion. . The temperature of the system at this time is preferably from the boiling point of the organic solvent (S) to 180 ° C, and particularly preferably from the boiling point of the organic solvent (S) + 10 ° C to 120 ° C. The pressure of this system is preferably 0.1 to 2.0 MPa in gauge pressure, more preferably 0.2 to 1.5 MPa in gauge pressure, and further preferably 0.3 to 1.0 MPa in gauge pressure. is there. When the preparation of the swelling body and the preparation of this dispersion are performed in the same container, the heating and pressurizing conditions of the system at the start of the dispersion preparation are the same as the temperature and pressure at the end of the preparation of the swelling body. Preferably there is.
The temperature of the aqueous medium used here is preferably not lower than the boiling point of the organic solvent (S) and not higher than 120 ° C.,
Above all, it is more preferable that the boiling point of the organic solvent (S) is less than 100 ° C. and the temperature of the system at the start of the second step is −20 ° C. to the temperature of the system at the start of the second step. preferable.

Furthermore, the temperature for producing the swollen body in the first step and the temperature for producing the initial aqueous dispersion in the second step are both the self-water-dispersible thermoplastic resin (P It is preferable that the temperature is lower than the melting point or softening point of the above), and it may be a temperature not higher than the glass transition temperature (Tg) of the self-water-dispersible thermoplastic resin (P), but above all, the organic solvent (S). It is preferable that the temperature is not lower than the boiling point of 10 and higher than the glass transition temperature (Tg) by 10 to 50 ° C. The temperature for producing the swollen body in the first step and the temperature for producing the initial aqueous dispersion in the second step may be the same or different.

As a method for producing the aqueous dispersion of thermoplastic resin fine particles of the present invention, for example, the following methods (1) to (4) are typical production methods. As a first step, a self-water-dispersible thermoplastic resin (P) and an organic solvent (S) are charged in a closed container, and the self-water-dispersible thermoplastic resin (P) is stirred under heating, preferably under heating and pressurization. ) Is swollen with an organic solvent (S) to produce a swollen body, and then, in a second step, the obtained swollen body is treated with a mechanical shearing force such as stirring, preferably under heating and pressurization to neutralize the neutralizing agent. In an aqueous medium which may be contained, it is dispersed in the form of fine particles to obtain an initial aqueous dispersion, and then, as a third step,
A method for producing a dispersion in which the fine particles of the self-water-dispersible thermoplastic resin (P) are dispersed in an aqueous medium by removing the organic solvent (S) from the obtained initial aqueous dispersion.

After obtaining the swollen body in the same manner as in the first step, in a second step, the obtained swollen body and an aqueous medium which may contain a neutralizing agent are placed in a continuous emulsifying disperser. While being continuously supplied, the swelled body is dispersed in the aqueous medium in the form of fine particles by mechanical shearing force to form an initial aqueous dispersion, and then, as a third step, the obtained initial aqueous dispersion is treated with the organic solvent. A method for producing a dispersion in which the fine particles of the self-water-dispersible thermoplastic resin (P) are dispersed in an aqueous medium by removing (S).

In the first step, the self-water-dispersible thermoplastic resin (P) melted by melt-kneading with an extruder or the like, or the synthesized self-water-dispersible thermoplastic resin (P) in a melted state.
In addition, an organic solvent (S) is continuously supplied by a method such as press-fitting, and the self-water-dispersible thermoplastic resin (P) is swollen with the organic solvent (S) while being mixed to produce a swollen body. After cooling the obtained swollen body to a temperature below the melting point or softening point of the self-water-dispersible thermoplastic resin (P), as a second step, the swollen body obtained and the neutralizing agent may be contained. While continuously supplying a good aqueous medium to a continuous emulsification disperser, the swollen body is finely dispersed in the aqueous medium by a mechanical shearing force to form an initial aqueous dispersion, and then, as a third step, obtain A method for producing a dispersion in which the fine particles of the self-water-dispersible thermoplastic resin (P) are dispersed in an aqueous medium by removing the organic solvent (S) from the obtained initial aqueous dispersion.

Among these methods, the above method or method is preferable because an aqueous dispersion of thermoplastic resin particles can be obtained relatively easily. As the shape of the self-water-dispersible thermoplastic resin (P) used in the above methods and,
Since it can be made into a swollen body in a relatively short time, it is preferably in the form of particles, for example, a particle diameter of 1 to 7 mm.
Pellets, coarsely pulverized material that has passed through a screen having a pore size of 2 to 7 mm, and powder having an average particle diameter of 800 μm or less.

A more specific production example of the method for producing an aqueous dispersion of thermoplastic resin fine particles by the above method will be described below. First, a glass-made 2 L autoclave with a propeller blade was used, and the autoclave was charged with the particulate matter obtained by pulverizing the self-water-dispersible thermoplastic resin (P) and an organic solvent (S), and an inert gas was supplied. Introduce and pre-pressurize the inside of the autoclave by 0.05 to 0.5 MPa, then 10
After pressurizing the inside of the autoclave to 0.1 to 2.0 MPa (gauge pressure) by raising the temperature above the boiling point of the organic solvent (S) under agitation of ~ 300 rpm to partially vaporize the organic solvent (S). Then, the self-water-dispersible thermoplastic resin (P) is swollen with the organic solvent (S) to obtain a swollen body by stirring at 50 to 700 rpm for 3 to 60 minutes (first step).

Examples of the inert gas used for the preliminary pressurization include nitrogen gas, helium gas, neon gas, argon gas and the like, but nitrogen gas is preferable.

The swollen body obtained in this step is the self-water-dispersible thermoplastic resin (P) which has absorbed the organic solvent (S).
And the organic solvent (S) that remains without being absorbed by the self-water-dispersible thermoplastic resin (P), and is preferably observed as a mixture of translucent to cloudy paste (paste). In addition, for example, in a system of polyester resin and isopropyl alcohol, when the stirring speed is loosened to about 50 rpm, it is observed that isopropyl alcohol separates from the resin phase to form two phases, but this may also be possible.

After the swollen body is obtained in this manner, in the above method, an aqueous medium which has been heated in advance with stirring at 300 to 1500 rpm, for example, water or ammonia water is injected under pressure for 2 to 30 minutes. And then phase invert emulsify,
An initial aqueous dispersion in which the swelled body is dispersed in the form of fine particles is prepared (second step). At this time, the organic solvent (S) in the swollen body is locally boiling and refluxing, and the organic solvent (S) having a low affinity with the self-water-dispersible thermoplastic resin (P).
It is considered that the molecules of (3) form an environment that facilitates separation from the self-water-dispersible thermoplastic resin (P) and facilitates phase inversion emulsification.

Further, in the above method, after obtaining the swelled body, a continuous emulsification disperser, for example, a high-speed rotary continuous machine in which a ring-shaped stator having a slit and a ring-shaped rotor having a slit are coaxially provided. The swollen body is continuously dispersed in an aqueous medium in the form of fine particles using an emulsifying disperser or the like to prepare a dispersion (second step). In this case, the swollen body and the aqueous medium may be fed into a continuous emulsification disperser under predetermined temperature and pressure conditions, and the rotor may be rotated at 300 to 10,000 rpm (see, for example, Patent Document 7).

[0081]

[Patent Document 7] Japanese Unexamined Patent Publication No. 09-311502 (6th
(See page 8 and Figures 1 to 4)

After obtaining the dispersion in which the swelling body is dispersed in the form of fine particles, the fine particles of the self-water-dispersible thermoplastic resin (P) are obtained by removing the organic solvent (S) from the obtained dispersion. A dispersion dispersed in an aqueous medium is obtained (3rd
Process). Examples of the method of removing the organic solvent (S) include a method of spraying in a decompression chamber, a method of forming a thin film on the inner surface of the desolvation can wall, a method of passing a desolvation can containing a solvent absorbing filler, and the like. Can be mentioned. As an example of a method for removing the organic solvent (S), a removal method using a rotary evaporator will be described below. Sample volume; 500 ml container; 2 L eggplant-shaped flask rotation speed; 60 rpm Bath temperature; 47 ° C. Decompression degree: 1.33 K over 20 minutes from 13.3 KPa
Increase the decompression degree to Pa, then continue for 10 minutes at 1.33 KPa
To remove the solvent.

When the resin fine particles in the aqueous dispersion of thermoplastic resin fine particles are used as a powder coating material or a hot melt adhesive, or when the generated particles are taken out as powder such as toner, the resin fine particles are dispersed. The removal of the organic solvent (S) from the dispersion is preferably performed immediately after the production of the dispersion. This is because if the dispersion is stored for a long time while the organic solvent (S) is contained, the resin fine particles in the dispersion tend to spontaneously aggregate.

In the method for producing an aqueous dispersion of thermoplastic resin fine particles of the present invention, the average particle diameter of the resin fine particles in the aqueous dispersion of thermoplastic resin fine particles is in the range of about 0.01 to 50 μm by changing various production conditions. It is possible to freely control within.

In the method for producing an aqueous dispersion of thermoplastic resin fine particles of the present invention, in order to control the average particle diameter of the resin fine particles in the obtained dispersion to be small, for example, the following means may be used. The hydrophilic segment concentration such as the concentration of acid groups or neutralized acid groups in the self-water-dispersible thermoplastic resin (P) is increased. When a thermoplastic resin that can be dispersed in an aqueous medium by neutralization is used as the self-water-dispersible thermoplastic resin (P), the amount of the neutralizing agent is increased. The amount of the organic solvent (S) used with respect to the self-water-dispersible thermoplastic resin (P) is increased. Raise the temperature during dispersion production. Increase the stirring speed during dispersion production.

On the contrary, in the method for producing an aqueous dispersion of thermoplastic resin fine particles of the present invention, these conditions may be reversed in order to increase the average particle diameter of the resin fine particles in the obtained dispersion. In addition to the self-water-dispersible thermoplastic resin (P) and the organic solvent (S), other components, for example, a colorant (C) such as carbon black, an additive such as a magnetic powder, a wax, a charge control agent and the like are used. Also by
The average particle size of the resin fine particles in the dispersion becomes large.

The resin fine particles in the aqueous dispersion of thermoplastic resin fine particles obtained by the production method of the present invention are dispersed by controlling the conditions such as temperature, pH and electrolyte concentration of the obtained dispersion. It is also possible to associate the resin fine particles that are present with each other to grow into larger particles.

The organic solvent (S) used in the present invention also plays a role of an adhesive between the resin fine particles in the step of associating the resin fine particles in the dispersion described later. Usually, the desolvation in the third step is performed after this association step is completed. However, before the association step, the solvent is once removed and stored, and the required amount of the same or similar organic solvent is removed in the association step. It may be added again and then allowed to associate, and then the solvent may be removed.

Next, the electrophotographic toner of the present invention will be described. The toner for electrophotography of the present invention is obtained by separating the fine particles of the self-water-dispersible thermoplastic resin (P) from the dispersion obtained by the method for producing an aqueous dispersion of thermoplastic resin fine particles of the present invention, and drying. An electrophotographic toner containing fine particles.

Next, the electrophotographic toner of the present invention will be described. The toner for electrophotography of the present invention is obtained by separating the fine particles of the self-water-dispersible thermoplastic resin (P) from the dispersion obtained by the method for producing an aqueous dispersion of thermoplastic resin fine particles of the present invention, and drying. An electrophotographic toner containing fine particles, wherein the dispersion obtained by the method of the present invention is used as it is, resin fine particles are separated from the dispersion, and the fine resin particles obtained by drying are used. After obtaining a dispersion in which resin particles having a particle size smaller than the toner size are dispersed by the method of the present invention, it is mixed with a separately prepared dispersion in which resin particles having a particle size smaller than the toner size are dispersed, Resin obtained by associating the resin fine particles in the dispersion to form toner-size fine particles by appropriately controlling conditions such as temperature, pH, and electrolyte concentration of the obtained dispersion, separating the particles, and drying. Slight It includes electrophotographic toner obtained by using the child.

Examples of the electrophotographic toner of the present invention include the electrophotographic toners shown in (1) to (4) below.

(1) In the method for producing an aqueous dispersion of thermoplastic resin fine particles according to the present invention, the self-water dispersible thermoplastic resin is used in the first step of swelling the self-water dispersible thermoplastic resin (P) with an organic solvent (S). After obtaining a dispersion in which fine colored resin particles obtained by using the colorant (C) together with the resin (P) are dispersed in an aqueous medium, the self-water-dispersible thermoplastic resin (P) is obtained from the obtained dispersion. An electrophotographic toner comprising fine particles obtained by separating and drying the fine particles of. An additive such as wax, magnetic powder, a charge control agent, etc. can be used together with the colorant (C). In this case, the average particle size of the colored resin particles in the dispersion is the toner size, for example, 1
It is preferably 10 μm.

(2) After obtaining a dispersion in which colored resin fine particles are dispersed in an aqueous medium in the same manner as in the above (1), the surface potential of the resin fine particles is reduced by a method such as adding a reverse neutralizing agent. Obtained by associating dispersed resin fine particles with each other to form a dispersion of colored resin particles having a larger average particle size, then removing the organic solvent (S), separating the fine particles, and then drying. An electrophotographic toner using fine particles. The removal of the organic solvent (S) may be performed after the resin particles are associated with each other. Further, an additive such as wax, magnetic powder, a charge control agent and the like can be used together with the colorant (C). In this case, the average particle diameter of the colored resin fine particles in the dispersion before association is preferably 0.01 to 1 μm,
The average particle diameter of the colored resin fine particles after association is preferably the toner size.

(3) After obtaining a dispersion in which colored resin fine particles are dispersed in an aqueous medium in the same manner as in the above (1), the resin fine particles are allowed to associate with each other in the same manner as in the above (2) to obtain a larger average particle size. Of colored resin particles (core particles) having a diameter and then mixed with an aqueous dispersion of resin fine particles for a shell layer, which is separately manufactured, and dispersed in the same manner as in (2) above (core particles). (Particles) are associated with resin fine particles for a shell layer to form a dispersion of colored resin particles having a core / shell structure, then the organic solvent (S) is removed, fine particles are separated, and then dried. An electrophotographic toner using fine particles. The removal of the organic solvent (S) may be performed after the resin particles are associated with each other. In this case, the average particle size of the colored resin fine particles in the dispersion before the association is 0.01 to
The average particle diameter of the colored resin fine particles after the end of the association is preferably the toner size.

The resin fine particles for the shell layer used in (3) above are composed of the self-water-dispersible thermoplastic resin (P) having a Tg of 1 to 40 ° C. higher than the glass transition temperature (Tg) of the resin particles for the core. When resin particles or resin fine particles are prepared using a charge control agent described later, resin particles prepared by using a large amount of the charge control agent are preferable.

(4) A self-water-dispersible thermoplastic resin (P) is swollen with an organic solvent (S) to obtain a swollen body, and then the swollen body is dispersed in an aqueous medium in the form of fine particles. Then, the organic solvent (S) was removed from the obtained dispersion to obtain a dispersion in which the fine particles of the self-water-dispersible thermoplastic resin (P) were dispersed in an aqueous medium, and then separately prepared. Resin fine particles and colorant particles dispersed by mixing with an aqueous dispersion of a colorant or a separately produced aqueous dispersion of colored resin fine particles and reducing the surface potential of the resin fine particles by a method such as addition of a reverse neutralizing agent. Alternatively, a toner for electrophotography, which comprises using fine particles obtained by associating colored resin fine particles to form a dispersion of colored resin particles having a larger average particle size, then separating the fine particles, and then drying. In this case, an additive such as wax, magnetic powder, charge control agent or the like can be used together with the colorant (C), and an aqueous dispersion of resin fine particles containing the additive, magnetic powder, charge control agent or the like. It is also possible to use and combine. Further, the removal of the organic solvent (S) may be performed after the resin fine particles are associated with the colorant particles or the colored resin fine particles. The average particle size of the fine particles in each dispersion used here is preferably 0.01 to 1 μm, and the average particle size of the colored resin fine particles after association is preferably the toner size.

In the separately prepared aqueous dispersion of the coloring agent or the separately prepared aqueous dispersion of the colored resin fine particles used in the above (4), the coloring agent or the colored resin fine particles are finely dispersed in the aqueous medium. Anything,
Although not particularly limited, for example, an aqueous dispersion obtained by emulsifying a colorant with a surfactant or the like, an aqueous dispersion obtained by heating and melting a colorant (C) and a resin, and then dispersing in water containing the dispersant, An aqueous dispersion prepared by dissolving a self-water-dispersible resin in which a colorant (C) is dispersed in an organic solvent, and then adding water thereto to carry out phase inversion emulsification, a self-water-dispersible thermoplastic resin (P And an aqueous dispersion obtained by using a colorant (C) together when swelling the) with an organic solvent (S). Among them, the aqueous dispersion obtained by the production method of the present invention is preferable. The concentration of the colorant (C) in these aqueous dispersions is 5 to 5 times the concentration of the colorant of the target toner.
It is preferably 10 times.

Examples of the colorant (C) include carbon black, red iron oxide, dark blue, titanium oxide, nigrosine dye (CINo.50415B), aniline blue (CINo.50).
405), Calco Oil Blue (CINo.azoic Blue3),
Chrome Yellow (CINo.14090), Ultramarine Blue (CINo.77103), DuPont Oil Red (CINo.2)
6105), Quinoline Yellow (CINo.47005), Methylene Blue Chloride (CINo.52015), Phthalocyanine Blue (CINo.74160), Malachite Green Oxalate (CINo.74160), Malachite Green Oxalate (CINo.42000), Lamp Black (CINo.42000). CINo.77266),
Rose Bengal (CI No.45435) and the like can be mentioned.

The content of the colorant (C) is preferably 1 to 20 parts by weight based on 100 parts by weight of the self-water-dispersible thermoplastic resin (P). These colorants may be used either individually or in combination of two or more.

The process and phenomenon of "association" referred to in the production method of the present invention will be described below. Generally, the resin fine particles in the thermoplastic resin fine particle aqueous dispersion as obtained by the production method of the present invention are stably present in the aqueous medium without agglomeration due to electrostatic repulsion force derived from the surface charge, At the same time, van der Waals force exerts an attractive force between the resin particles. Therefore, if the surface charge of the resin particles is appropriately reduced by some action, the attractive force becomes larger than the electrostatic repulsion force, the resin fine particles start to aggregate, and become a dispersion of resin particles grown to a larger particle diameter. This is called a meeting in the present invention. The temperature of this association is preferably from the glass transition temperature (Tg) of the self-water-dispersible thermoplastic resin (P) to the glass transition temperature + 50 ° C., and the boiling point of the organic solvent (S) existing in the system during the association step. Due to the relationship of 0.
It is more preferable to heat under a pressure of 1 to 1.0 MPa (gauge pressure). The time required for the meeting is usually 2 to 12 hours, preferably 4 to 10 hours. In addition, the association is performed with gentle stirring, for example, 10 to 100 rpm with an anchor blade.
It is recommended to carry out the stirring under a moderate number of rotations.

As a method for reducing or eliminating the surface charge of the resin particles, for example, dilute hydrochloric acid, dilute sulfuric acid, acetic acid,
A method of adding an acid such as formic acid or carbonic acid as a so-called reverse neutralizing agent can be mentioned. At this time, metal salts such as sodium chloride, potassium chloride, aluminum sulfate, ferric sulfate, and calcium chloride, which are called salting-out agents, and metal complexes such as calcium, aluminum, magnesium, and iron may be added, if necessary. . In addition, a surfactant may be used, if necessary, for the purpose of dispersing the colorant in the association step and controlling the progress of the association.

Examples of the surfactant include anionic surfactants such as sodium dodecylbenzene sulfonate, sodium lauryl sulfate and sodium alkyldiphenyldisulfonate, cationic surfactants such as trimethylstearyl ammonium chloride, and alkylphenoxypoly ( Examples thereof include nonionic surfactants such as ethyleneoxy) ethanol, which can be appropriately selected and used.

The method for producing the electrophotographic toner of the present invention comprises:
It is particularly preferable for producing an electrophotographic toner having a particle size of 1 to 10 μm.

According to the production method of the present invention, a water-dispersed resin or toner composed of spherical resin particles having no sharp point portion in the shape can be produced. Here, the term "spherical" refers to a wide range of concepts including an elliptical shape, a distorted spherical shape (potato shape), etc. as well as a true spherical shape.

In the method for producing an aqueous dispersion of thermoplastic resin fine particles of the present invention and the electrophotographic toner of the present invention, additives such as magnetic powder and wax may be used as necessary.
These are preferably kneaded with the self-water-dispersible thermoplastic resin (P) in advance to form a kneaded product. These additives may be used alone or in combination of two or more.

As the magnetic powder, for example, magnetite,
Examples include simple metals such as ferrite, cobalt, iron and nickel, and alloys thereof.

The wax can be used as an offset preventive agent for the electrophotographic toner. Examples of the wax include synthetic waxes such as polypropylene wax, polyethylene wax, Fischer-Tropsch wax, stearylbisamide, and oxidized wax, and natural waxes such as carnauba wax and rice wax.

If a charge control agent is used, a toner having good charging characteristics can be obtained. As the charge control agent, for example,
Nigrosine-based electron-donating dyes, naphthenic acid, metal salts of higher fatty acids, alkoxylated amines, quaternary ammonium salts, alkylamides, metal complexes, pigments, positive charge control agents such as fluorination activators, and electron-accepting agents. Examples thereof include organic complexes, chlorinated paraffins, chlorinated polyesters, and negative charge control agents such as sulfonylamines of copper phthalocyanine.

When using the charge control agent, it is preferable to dissolve these charge control agents in the organic solvent (S) in advance and then add them to the self-water-dispersible thermoplastic resin (P). When a toner comprising a core particle and a shell layer is produced, if a charge control agent is used in producing the shell layer, a toner having the charge control agent arranged in the shell layer can be produced.

In the present invention, the ratio of the non-volatile content in the thermoplastic resin fine particle aqueous dispersion is such that the aqueous dispersion is left to stand in a vacuum dryer at 100 ° C. under 0.1 KPa for 3 hours. It was calculated from the change in body weight. Further, the particle size of the fine particles is 0.001 to 2 μm, and the particle size is measured by Lee.
MICROTRACUP made by ds + Northrup
The particle size of 1 to 40 μm was measured using Beckman Coulter Multisizer ^TM 3.

The amount of residual solvent in the thermoplastic resin fine particle aqueous dispersion was measured by gas chromatography under the following conditions. Measuring instrument; Shimadzu GC-17A column; ULBON HR-20M (PPG) column temperature; 80-150 ° C temperature rising rate; 10 ° C / min.

[0112]

EXAMPLES The present invention will be specifically described below with reference to synthesis examples, examples and comparative examples. Parts and% in the examples are by weight unless otherwise specified.

Synthesis Example 1 [Synthesis of Carboxyl Group-Containing Polyester Resin (I)] 192 parts of ethylene glycol, 324 parts of neopentyl glycol, 996 parts of terephthalic acid and 1.0 part of tetrabutyl titanate were attached to a rectification column and a condenser. A glass 2-liter four-necked flask was charged, the temperature was gradually raised under a nitrogen stream, and the reaction was carried out at 240 ° C. for 8 hours. The amount of ethylene glycol and neopentyl glycol entrained is analyzed by analyzing the condensed water that distills with the progress of the reaction, and the reaction proceeds while supplementing it, and the solid at room temperature has an acid value of 10 (mg KO
H / g) of polyester resin (I-1) was obtained. Glass transition temperature (Tg) of polyester resin (I-1) by differential thermal measurement (DSC) method, softening point by ring and ball method, 1/2 drop temperature (T1 / 2) in flow tester, gel content, Mw,
Table 3 shows Mn, Mw / Mn and acid value.

Synthetic Examples 2 to 5 (Same as above) Carboxyl group-containing polyester resin (I-) was prepared in the same manner as in Synthetic Example 1 except that raw materials were used in the composition shown in Table 1.
2) to (I-5) were obtained. Polyester resin (I-2)
To (I-5) glass transition temperature (Tg) by differential calorimetry (DSC) method, softening point by ring and ball method, 1/2 drop temperature (T1 / 2) in flow tester, gel content, Mw, Mn, M
The w / Mn and acid value are shown in Table 3.

Synthesis Example 6 [Synthesis of carboxyl group-containing polyester resin (II)] Ethylene glycol 224 was added to a glass four-necked flask.
Part, neopentyl glycol 250 parts, terephthalic acid 9
96 parts, Epicron 830 [Dainippon Ink and Chemicals, Inc., bisphenol F type bifunctional epoxy resin] 1
7 parts, Cardura E10 (manufactured by Shell Japan Co., neodecanoic acid glycidyl ester) and 1.0 part dibutyltin oxide were added, and the temperature was gradually raised under a nitrogen stream and the reaction was carried out at 245 ° C for 18 hours. The condensed water distilled out along with the progress of the reaction was analyzed to measure the amounts of the accompanying ethylene glycol and neopentyl glycol, and the reaction was carried out while supplementing. A polyester resin (II-1) having a solid at room temperature and an acid value of 9 was obtained. Glass transition temperature (Tg) of polyester resin (II-1) measured by differential calorimetry (DSC),
Table 4 shows the softening point by the ring and ball method, the 1/2 drop temperature (T1 / 2) in the flow tester, the gel content, Mw, Mn and Mw / Mn and the acid value.

Synthetic Example 7 and Synthetic Example 8 (Same as above) Carboxyl group-containing polyester resin (II-
2) and polyester resin (II-3) were obtained. Polyester resin (II-1) and polyester resin (II-
3) Glass transition temperature (Tg) by differential calorimetry (DSC) method, softening point by ring and ball method, 1 by flow tester
/ 2 fall temperature (T1 / 2), gel content, Mw, Mn and Mw /
Table 4 shows Mn and acid value.

[0117]

[Table 1]

[0118]

[Table 2]

The abbreviations in Tables 1 and 2 are as follows. PTBBA: Paratertiary butyl benzoic acid SBASS: Sulfobenzoic acid sodium salt BPA-EO: Ethylene oxide 2.2 mol adduct of bisphenol A CHDM: Cyclohexanedimethanol 830: Bisphenol F type manufactured by Dainippon Ink and Chemicals, Inc. Epoxy resin Epicron 830 850: Bisphenol A type epoxy resin Epicuron 850 CE-10 manufactured by Dainippon Ink and Chemicals, Inc .: Neodecanoic acid glycidyl ester cardura E-10 manufactured by Shell Japan.

[0120]

[Table 3]

[0121]

[Table 4]

Example 1 The solubility of the polyester resin (I-4) and the polyester resin (II-1) in acetone was determined under the condition that the concentration of each resin was 10%, according to ASTM D3132-.
84 (Reapproved 1996), 7.2.1.1.1 to 7.2.
When the determination method described in 1.3 is used, the polyester resin (I-4) is a “solution on the boundary line” and the polyester resin (II-1) is “insoluble” in the determination category of the determination method. "Met.

45 parts of a coarsely pulverized product of polyester resin (I-4) (passed through a screen having a hole diameter of 3 mm; the same applies hereinafter), 55 parts of a coarsely pulverized product of polyester resin (II-1) and 100 parts of acetone were added. It was charged in a 2 L autoclave equipped with a propeller blade, pre-pressurized to 0.2 MPa with nitrogen gas, and heated to 90 ° C. in the system while rotating the propeller blade at 100 rpm. At this time, the pressure inside the autoclave had increased to 0.45 MPa. After the temperature in the system reached 90 ° C., the rotation speed of the propeller blade was increased to 500 rpm and acetone was absorbed into the particulate matter while stirring for 10 minutes to obtain a translucent paste-like swelling body. After that, increase the rotation speed of the propeller blade to 1000 rpm and
Ammonia water with a concentration of 0.123% preheated to 0 ° C 4
02 parts of the mixture was pressure-injected over 5 minutes to obtain an emulsion-colored initial aqueous dispersion in which the swollen body was dispersed in water in the form of fine particles. With stirring, the initial aqueous dispersion obtained was cooled with water to 30 ° C., taken out, and dried using a rotary evaporator.
Acetone was distilled off under the condition of 7 ° C. for 30 minutes to obtain a polyester resin fine particle aqueous dispersion. When the resin particle diameter in the obtained polyester resin fine particle aqueous dispersion was measured,
The average particle size was 0.16 μm. When the amount of residual acetone was measured by gas chromatography, it was 360 ppm. The nonvolatile content of the obtained polyester resin fine particle aqueous dispersion was 25%.

Example 2 Carbon black manufactured by Cabot Corporation (Regal R33
0) 100 parts, polyester resin (I-4) 45 parts and polyester resin (II-1) 55 parts were melt-kneaded using a pressure kneader to prepare a kneaded product. 100 parts of coarsely crushed product of this kneaded material and 100 parts of acetone were mixed with a propeller blade.
Charged to L autoclave, 0.2MPa with nitrogen gas
Pre-pressurization was performed and the system was heated to 90 ° C. while rotating the propeller blade at 100 rpm. At this time, the pressure inside the autoclave had increased to 0.45 MPa. After the temperature in the system reached 90 ° C., the rotation speed of the propeller blade was increased to 500 rpm, and the coarsely ground product was made to absorb acetone while stirring for 10 minutes to obtain a black paste-like swollen body. After that, increase the rotation speed of the propeller blade to 1000 rpm,
Ammonia water with a concentration of 0.31% that was preheated to 90 ° C 4
05 parts was injected under pressure for 5 minutes to obtain a black initial aqueous dispersion in which the swelling body was dispersed in water in the form of fine particles. The initial aqueous dispersion thus obtained was cooled with water to 30 ° C. while being stirred, taken out, and stirred at 47 ° C. using a rotary evaporator.
Acetone was distilled off under the condition of 30 ° C. for 30 minutes to obtain a polyester resin fine particle aqueous dispersion. When the resin particle diameter in the obtained polyester resin fine particle aqueous dispersion was measured, the average particle diameter was 0.3 μm. When the amount of residual acetone was measured by gas chromatography, it was 300 ppm. The nonvolatile content of the obtained water-dispersed polyester resin was 25%.

Example 3 Polypropylene wax manufactured by Sanyo Chemical Co., Ltd. “Viscole 55”
0P "100 parts, 100 parts of coarsely pulverized polyester resin (I-4) and 100 parts of acetone were used with 2 with a propeller blade.
Charged to L autoclave, 0.2MPa with nitrogen gas
Was pre-pressurized, and the system was heated to 150 ° C. while rotating the propeller blade at 100 rpm. At this time, the pressure inside the autoclave had increased to 1.25 MPa.
After the temperature in the system reached 150 ° C., the rotational speed of the propeller blade was increased to 500 rpm and the coarsely ground product was allowed to absorb acetone while stirring for 10 minutes to obtain a cloudy paste-like swelling body. Thereafter, 405 parts of ammonia water having a concentration of 0.31% preheated to 90 ° C. by increasing the rotation speed of the propeller blade to 1000 rpm was pressure-injected over 5 minutes to initially disperse the swollen body in fine particles in water. An aqueous dispersion was obtained. The initial aqueous dispersion thus obtained was cooled with water to 30 ° C. while being stirred, taken out, and stirred at 47 ° C. using a rotary evaporator.
Acetone was distilled off under the condition of 30 ° C. for 30 minutes to obtain a polyester resin fine particle aqueous dispersion. When the resin particle diameter in the obtained polyester resin fine particle aqueous dispersion was measured, the average particle diameter was 0.8 μm. When the amount of residual acetone was measured by gas chromatography, it was 200 ppm. The nonvolatile content of the obtained polyester resin fine particle aqueous dispersion was 25%.

Example 4 Orient Chemical charge control agent "Bontron E-80" 1
00 parts, 45 parts of polyester resin (I-4) and 55 parts of polyester resin (II-1) were melt-kneaded using a pressure kneader to prepare a kneaded product. Coarse crushed product 1
00 parts and 100 parts of acetone were charged into a 2 L autoclave equipped with a propeller blade, pre-pressurized to 0.2 MPa with nitrogen gas, and heated to 90 ° C. in the system while rotating the propeller blade at 100 rpm. At this time, the pressure inside the autoclave had increased to 0.45 MPa. 9 in the system
After the temperature reached 0 ° C., the rotation speed of the propeller blade was increased to 500 rpm and acetone was absorbed in the coarsely pulverized product while stirring for 10 minutes to obtain a light purple paste-like swollen body. After that, increase the rotation speed of the propeller blade to 1000 rpm and
0.25% ammonia water 404 preheated to ℃
A part was injected under pressure for 5 minutes to obtain a light purple initial aqueous dispersion in which the swollen body was dispersed in fine particles. The initial aqueous dispersion thus obtained was cooled with water to 30 ° C. while being stirred, taken out, and stirred at 47 ° C. using a rotary evaporator.
Acetone was distilled off under the conditions of 30 ° C. for 30 minutes to obtain a light purple polyester resin fine particle aqueous dispersion. When the resin particle diameter in the obtained polyester resin fine particle aqueous dispersion was measured, the average particle diameter was 0.3 μm. When the amount of residual acetone was measured by gas chromatography, it was 300 ppm.
Met. The nonvolatile content of the obtained polyester resin fine particle aqueous dispersion was 25%.

Example 5 In an autoclave equipped with an anchor wing and a condenser,
Polyester resin fine particle aqueous dispersion 28 obtained in Example 1
0 part, 56 parts of the polyester resin fine particle aqueous dispersion obtained in Example 2 as a colorant masterbatch, 40 parts of the polyester resin fine particle aqueous dispersion obtained in Example 3 as an offset inhibitor masterbatch and a charge control agent masterbatch Twenty-four parts of the polyester resin fine particle aqueous dispersion obtained in Example 4 was charged, 40 parts of acetone was added while rotating the anchor blade at 50 rpm, and the temperature was raised to 50 ° C. Thereafter, while further raising the temperature to 90 ° C. over 6 hours, 20 parts of 2% dilute hydrochloric acid, 20 parts of 1% aluminum sulfate solution and 10% 1% sodium dodecylbenzenesulfonate solution.
Each part was dropped to associate the resin particles with each other to obtain a polyester resin fine particle aqueous dispersion. Acetone was distilled off using a rotary evaporator under the conditions of 47 ° C. for 60 minutes, washing with ion-exchanged water was repeated 3 times, and then dehydration drying was performed to obtain polyester resin particles. The polyester resin particles thus obtained and 0.3% of Aerosil R-974 (manufactured by Nippon Aerosil Co., Ltd., based on the weight of the resin particles) were mixed by a Henschel mixer, and particles (toner) having an average particle diameter of 6.0 μm. Got The amount of residual acetone in the obtained toner was measured by gas chromatography to be 20 ppm.
(Detection limit) or less.

Example 6 In an autoclave equipped with an anchor wing and a condenser,
Polyester resin fine particle aqueous dispersion 28 obtained in Example 1
0 parts, Cabot carbon black (Regal R
330) 0.05 part of surfactant and 1 part of ion-exchanged water in 5 parts
2 parts by weight of a colorant treated with a homogenizer by adding 0 parts, a polypropylene wax "Viscor 550P" manufactured by Sanyo Kasei Co., Ltd. in terms of solid content, and a charge control agent "T-77" manufactured by Hodogaya Chemical Co., Ltd. 1. 5 parts acetone 3
The melted material was charged in 5 parts and the temperature was raised to 50 ° C. while rotating the anchor blades at 50 rpm. After that, increase the temperature to 6
20 parts of 2% dilute hydrochloric acid while heating to 90 ° C. over time,
20 parts of a 1% aluminum sulfate solution and 10 parts of a 1% sodium dodecylbenzene sulfonate solution were added dropwise to associate the resin particles to obtain a polyester resin fine particle aqueous dispersion. 47 using a rotary evaporator
Acetone was distilled off under the condition of 60 ° C. for 60 minutes, washing with ion-exchanged water was repeated 3 times, and then dehydration drying was performed to obtain polyester resin fine particles. With the obtained polyester resin fine particles,
0.3% of Aerosil R- based on the weight of the resin particles
And 974 with a Henschel mixer to obtain an average particle size of 6.
Particles (toner) of 0 μm were obtained. When the amount of residual acetone in the obtained toner was measured by gas chromatography, it was 20 ppm (detection limit) or less.

Example 7 Polyester resin (I-2) and polyester resin (II-2) were evaluated for solubility in acetone in the same manner as in Example 1 under the condition that the resin concentration was 10%. The judgment classification of the resin (I-2) was "boundary line solution", and the judgment classification of the polyester resin (II-2) was "insoluble".

36 parts of polyester resin (I-2), 54 parts of polyester resin (II-2), carbon black MA
-11 (Mitsubishi Chemical) 7 parts, Bontron E-81 (Orient Chemical charge control agent) 1.5 parts and Viscole 5
Add 3.5 parts of 50P (Sanyo Kasei polypropylene wax) and mix with a Henschel mixer.
A kneaded material was prepared by kneading with a pressure kneader. 100 parts of coarsely pulverized product of this kneaded material and 30 parts of acetone were charged into a 2 L autoclave equipped with a propeller blade, and 0.2 M of nitrogen gas was charged.
The pressure was pre-pressurized to Pa and the system was heated to 90 ° C. while rotating the propeller blade at 100 rpm. At this time, the pressure inside the autoclave had increased to 0.40 MPa. After the temperature in the system reached 90 ° C., the rotation speed of the propeller blade was increased to 500 rpm, and the coarsely ground product was made to absorb acetone while stirring for 10 minutes to obtain a black paste-like swollen body. Then, 401.5 parts of aqueous ammonia having a concentration of 0.094% preheated to 90 ° C. was pressure-injected into the autoclave over 5 minutes to obtain a black initial aqueous dispersion in which the swollen body was dispersed in fine particles. Obtained. The initial aqueous dispersion obtained was taken out by cooling with water to 30 ° C. while continuing stirring, and acetone was distilled off using a rotary evaporator at 47 ° C. over 30 minutes, washed once with ion-exchanged water, and then dehydrated and dried. Then, polyester resin particles were obtained. The obtained polyester resin particles and 0.3% of Aerosil R-974 with respect to the weight of the resin particles were mixed with a Henschel mixer to obtain particles (toner) having an average particle size of 6.5 μm. When the amount of residual acetone in the obtained toner was measured by gas chromatography, it was 20 ppm (detection limit) or less.

Example 8 In the same manner as in Example 1, the polyester resin (I-1), the polyester resin (I-3) and the polyester resin (II
-3) was dissolved in acetone under the condition that the resin concentration was 10%, the polyester resin (I
The judgment classification of -1) and polyester resin (I-3) was "boundary line solution", and the judgment classification of polyester resin (II-3) was "insoluble".

70 parts of polyester resin (I-1), 30 parts of polyester resin (II-3), 100 parts of carbon black (Regal R330) manufactured by Kyabot and 5 parts of VISCOL 550P were melt-kneaded with a pressure kneader to obtain a kneaded product. Prepared. 100 parts of coarsely pulverized material of this kneaded product and 100 parts of acetone were charged into a 2 L autoclave equipped with a propeller blade, and prepressurized to 0.2 MPa with nitrogen gas, and 100
The system was heated to 70 ° C. while rotating the propeller blades at rpm. At this time, the pressure inside the autoclave had increased to 0.42 MPa. After the temperature in the system reached 70 ° C., the rotational speed of the propeller blade was increased to 500 rpm and the coarsely ground product was allowed to absorb acetone while stirring for 10 minutes to obtain a black paste-like swollen body. Thereafter, 405 parts of ammonia water having a concentration of 0.31% preheated to 70 ° C. was pressure-injected over 5 minutes to disperse the swollen body in the form of fine particles, and the initial black color having an average particle diameter of 0.8 μm was obtained. An aqueous dispersion was obtained. The initial aqueous dispersion obtained was immediately water-cooled to 50 ° C. with continuous stirring, and the rotation speed of the propeller blade was 50 rpm.
2% while lowering to 90 ° C over 4 hours
20 parts of dilute hydrochloric acid, 20 parts of a 1% aluminum sulfate solution and 10 parts of a 1% sodium dodecylbenzene sulfonate solution were added dropwise to associate the resin particles to obtain a polyester resin fine particle aqueous dispersion. Acetone was distilled off using a rotary evaporator under the conditions of 47 ° C. and 60 minutes,
After repeating washing three times with ion-exchanged water, the solid content concentration was adjusted to 25% to obtain a black polyester resin fine particle aqueous dispersion for core. Polyester resin fine particles for core Average particle size of resin particles in the aqueous dispersion is 4.8 μm
Met.

Instead of 45 parts of polyester resin (I-4), 55 parts of polyester resin (II-1) and 100 parts of acetone, 70 parts of polyester resin (I-3), 30 parts of polyester resin (II-1), Orient Chemical charge control agent "Bontron E-80" 2 parts and acetone 10
Ammonia water 4 using 0 part and a concentration of 0.123%
Ammonia water 40 with a concentration of 0.22% instead of 02 parts
An aqueous polyester resin particle dispersion for cores for shell layers was prepared in the same manner as in Example 1 except that 3.5 parts were used. When the resin particle diameter in the obtained polyester resin fine particle aqueous dispersion for core for shell layer was measured, the average particle diameter was 0.3 μm. The non-volatile content of the aqueous dispersion of polyester resin fine particles for shell layer was 25%.

Polyester resin fine particle aqueous dispersion 1 for core was added to an autoclave equipped with anchor blades and a condenser.
00 parts and 10 parts of acetone were added, and the mixture was stirred for 2 hours while rotating the anchor blade at 50 rpm. 50 parts of polyester resin fine particle aqueous dispersion for core for shell layer was added thereto, and the temperature was raised to 50 ° C. and further raised to 90 ° C. over 6 hours, 2 parts of dilute hydrochloric acid 20 parts, 1% aluminum sulfate solution 2
0 parts and 10 parts of a 1% sodium dodecylbenzene sulfonate solution were added dropwise to associate the resin particles to obtain a polyester resin fine particle aqueous dispersion. Acetone was distilled off using a rotary evaporator under the conditions of 47 ° C. for 30 minutes, washed with ion-exchanged water 3 times, and then dehydrated and dried to obtain polyester resin particles. The obtained polyester resin particles and 0.3% of Aerosil R-974 with respect to the weight of the resin particles were mixed by a Henschel mixer to obtain a toner having core-shell structured particles having an average particle diameter of 5.9 μm. When the amount of residual acetone in the obtained toner was measured by gas chromatography, it was 20 ppm (detection limit) or less.

Example 9 When the solubility of the polyester resin (I-5) in acetone was determined in the same manner as in Example 1 under the condition that the resin concentration was 10%, the polyester resin (I-5) was determined. The division was "borderline solution".

Coarse pulverized product 1 of polyester resin (I-5)
00 parts and 100 parts of acetone were charged into a 2 L autoclave equipped with a propeller blade, pre-pressurized to 0.2 MPa with nitrogen gas, and the system was heated to 90 ° C. while rotating the propeller blade at 100 rpm. At this time, the pressure inside the autoclave had increased to 0.45 MPa. 90 in the system
After the temperature reached ℃, the rotation speed of the propeller blade was increased to 500 rpm and the coarsely pulverized product was made to absorb acetone while stirring for 10 minutes to obtain a translucent paste-like swollen body. After that, increase the rotation speed of the propeller blade to 1000 rpm, and
Ion-exchanged water preheated to 0 ° C. was injected under pressure over 5 minutes to obtain a milky white initial aqueous dispersion in which the swollen body was dispersed in fine particles. The initial aqueous dispersion thus obtained was cooled with water to 30 ° C. while being continuously stirred and taken out, and acetone was distilled off at 47 ° C. for 30 minutes using a rotary evaporator to obtain an aqueous polyester resin particle dispersion. When the resin particle diameter in the obtained polyester resin fine particle aqueous dispersion was measured, the average particle diameter was 0.02 μm. The amount of residual acetone measured by gas chromatography was 25 ppm. The non-volatile content of the obtained polyester resin fine particle aqueous dispersion was 25%.

Example 10 In the same manner as in Example 1 except that isopropyl alcohol was used instead of acetone, a polyester resin (I-
When the solubility of 4) and the polyester resin (II-1) were evaluated, both judgment categories were “insoluble”.

Coarse pulverized product 4 of polyester resin (I-4)
5 parts, 55 parts of a coarsely pulverized product of polyester resin (II-1) and 100 parts of isopropyl alcohol were charged into a 2 L autoclave equipped with a propeller blade, and 0.2 MP was added with nitrogen gas.
It was pre-pressurized to a and heated to 90 ° C. while rotating the propeller blade at 100 rpm. At this time, the pressure inside the autoclave had increased to 0.42 MPa.
After the temperature in the system reached 90 ° C., the rotation speed of the propeller blade was increased to 500 rpm, and the coarsely pulverized product was made to absorb acetone while stirring for 10 minutes to obtain a translucent paste-like swelling body. Thereafter, 402 parts of ammonia water having a concentration of 0.123% preheated to 90 ° C. by increasing the number of revolutions of the propeller blade to 1000 rpm was pressure-injected over 5 minutes, and a swelling body was dispersed in water into fine particles to obtain a milky white. An initial aqueous dispersion of was obtained. The initial aqueous dispersion obtained was immediately cooled with water to 30 [deg.] C. while stirring and taken out, and the rotary evaporator was removed.
Was used to remove isopropyl alcohol by distillation at 47 ° C. for 30 minutes to obtain an aqueous dispersion of polyester resin fine particles. When the resin particle diameter in the obtained polyester resin fine particle aqueous dispersion was measured, the average particle diameter was 0.12 μm. The amount of residual isopropyl alcohol was measured by gas chromatography and found to be 50 ppm. The non-volatile content of the obtained polyester resin fine particle aqueous dispersion was 25%.

Comparative Example 1 Polyester resin (I-4) and polyester resin (I-4) were prepared in the same manner as in Example 1 except that the resin concentration was changed from 10% to 15%, and tetrahydrofuran was used instead of acetone. When the solubility of II-1) was evaluated, both judgment categories were "complete solution".

Coarse pulverized product 4 of polyester resin (I-4)
5 parts, 55 parts of a coarsely pulverized product of polyester resin (II-1) and 100 parts of tetrahydrofuran (THF) were charged into a 2 L autoclave equipped with a propeller blade to prepare a solution. 10
While rotating the propeller blades at 0 rpm, the system was heated until it reached 90 ° C. Then, the number of revolutions of the propeller blade was increased to 1000 rpm and preheated to 90 ° C. with a concentration of 0.12.
402 parts of 3% ammonia water was injected over 5 minutes to obtain a translucent milky white aqueous dispersion in which the resin was dispersed in fine particles. The aqueous dispersion thus obtained was immediately cooled with water to 30 ° C. with continuous stirring, taken out, and THF was distilled off at 47 ° C. for 30 minutes using a rotary evaporator to obtain a polyester resin fine particle aqueous dispersion. When the resin particle diameter in the obtained polyester resin fine particle aqueous dispersion was measured, the average distillation diameter was 0.18 μm. When the amount of residual acetone was measured by gas chromatography, it was 88.
It was as high as 0 ppm. The non-volatile content of the obtained polyester resin fine particle aqueous dispersion was 25%.

Comparative Example 2 The solubility of the polyester resin (I-2) and the polyester resin (II-2) was determined in the same manner as in Example 1 except that tetrahydrofuran was used instead of acetone. Both compartments were "complete solution".

Polyester resin (I-2) 36 parts Polyester resin (II-2) 54 parts Carbon black MA-
11 parts (manufactured by Mitsubishi Chemical), 1.5 parts Bontron E-81 (charge control agent manufactured by Orient Chemical) and 55
3.5 parts of 0P (polypropylene wax manufactured by Sanyo Kasei) was added, mixed with a Henschel mixer, and kneaded with a pressure kneader to prepare a kneaded product. A coarse pulverized product (100 parts) and THF (30 parts) were put into a 2 L autoclave equipped with a propeller blade to prepare a solution. While rotating the propeller blades at 100 rpm, the system was heated until it reached 90 ° C. After the temperature in the system reached 90 ° C, the rotation speed of the propeller blade was increased to 500 rpm and preheated to 90 ° C.
401.5 parts of 94% ammonia water was injected over 5 minutes to obtain a black aqueous dispersion in which the resin was dispersed in fine particles. The resulting aqueous dispersion was immediately cooled with water to 30 ° C. with stirring, taken out, and THF was distilled off at 47 ° C. for 60 minutes using a rotary evaporator, washed once with ion-exchanged water, and then dehydrated. It was dried to obtain polyester resin particles. With the obtained polyester resin particles,
0.3% of Aerosil R- based on the weight of the resin particles
974 (manufactured by Nippon Aerosil Co., Ltd.) was mixed with a Henschel mixer to obtain particles (toner) having an average particle size of 6.2 μm. When the amount of residual THF in the obtained toner was measured by gas chromatography, it was 600 ppm, and an odor was felt.

[0143]

INDUSTRIAL APPLICABILITY According to the production method of the present invention, an organic solvent (S) having a boiling point of less than 100 ° C., which is capable of swelling but not dissolving the self-water-dispersible thermoplastic resin (P), preferably an organic solvent compatible with water. After using a solvent to absorb the self-water-dispersible thermoplastic resin (P) with the organic solvent (S) to form a swollen body, phase inversion emulsification is performed to disperse the swollen body in the form of fine particles in an aqueous medium. Then, since the organic solvent is removed from the obtained dispersion, it is easy to remove the organic solvent, and an aqueous dispersion of thermoplastic resin fine particles having very little residual solvent remaining in the resin fine particles can be obtained. Further, the electrophotographic toner of the present invention containing the fine particles obtained by separating the resin fine particles from the thermoplastic resin fine particle aqueous dispersion obtained by the production method of the present invention and drying has the advantage that the residual solvent is extremely small. is there.

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] December 5, 2002 (2002.12.
5)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0042

[Correction method] Change

[Correction content]

The polyester resin (II) has a gel content of 0.2 to 0.7% by weight and a weight average molecular weight (Mw) of 200,000 to 1,000,000.
The polyester resin having a number average molecular weight (Mn) of 5,000 to 10,000 and Mw / Mn of 20 to 200 is more preferable.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 9/08 331 F term (reference) 2H005 AA01 AB02 CA08 EA03 EA06 4F070 AA47 AA74 AB03 AB09 AB11 AB21 AB22 AB23 AC36 AC39 AE04 AE28 CA02 CA13 CA20 CB02 CB12 4J002 AF02W BA01W BC12W BG02W CF04W CF04X CK02W FD096 GH00 HA07

Claims (12)

[Claims] 1. An organic solvent (S) having a boiling point of less than 100 ° C., which can swell the self-water-dispersible thermoplastic resin (P) without dissolving the self-water-dispersible thermoplastic resin (P).
A first step of producing a swollen body by swelling with
The second step of producing the initial aqueous dispersion by dispersing the swollen body in the form of fine particles in an aqueous medium, and the self-water-dispersible thermoplastic resin by removing the organic solvent (S) from the initial aqueous dispersion. A method for producing an aqueous dispersion of thermoplastic resin fine particles, which comprises a third step of producing a dispersion in which fine particles of the resin (P) are dispersed in the aqueous medium. 2. The method for producing an aqueous dispersion of thermoplastic resin fine particles according to claim 1, wherein the swollen body is produced by heating the self-water-dispersible thermoplastic resin (P) and the organic solvent (S). 3. In the first step, the self-water-dispersible thermoplastic resin (P) and the organic solvent (S) are heated under pressure to a temperature equal to or higher than the boiling point of the organic solvent (S) to form the swelled body. In the second step, the swollen body is dispersed in the aqueous medium into fine particles by a mechanical shearing force at a temperature of not less than the boiling point of the organic solvent (S) and not more than 120 ° C. in the second step to obtain the initial aqueous dispersion. The method for producing the thermoplastic resin fine particle aqueous dispersion according to claim 1, wherein the method comprises: 4. From the glass transition temperature (Tg) of the self-water-dispersible thermoplastic resin (P) in the first step, it is 10-5.
The swollen body is manufactured at a temperature higher by 0 ° C., and the initial aqueous dispersion is manufactured at a temperature 10 to 50 ° C. higher than the glass transition temperature (Tg) of the self-water-dispersible thermoplastic resin (P) in the second step. The method for producing an aqueous dispersion of thermoplastic resin particles according to claim 3. 5. The method for producing an aqueous dispersion of thermoplastic resin fine particles according to claim 3, wherein the organic solvent (S) is an organic solvent compatible with water. 6. The method for producing an aqueous dispersion of thermoplastic resin fine particles according to claim 3, wherein the organic solvent (S) is acetone and / or isopropyl alcohol. 7. A self-water-dispersible thermoplastic resin (P) 100.
The amount of the organic solvent (S) used is 10 to 200 parts by weight.
The thermoplastic resin fine particles according to claim 3, wherein the amount of water used is 70 to 400 parts by weight based on 100 parts by weight of the total of the self-water-dispersible thermoplastic resin (P) and the organic solvent (S). A method for producing an aqueous dispersion. 8. The method for producing an aqueous dispersion of thermoplastic resin fine particles according to claim 1, wherein the self-water-dispersible thermoplastic resin (P) is a polyester resin. 9. The self-water-dispersible thermoplastic resin (P) is a carboxyl group-containing polyester resin, and the aqueous medium is water containing a basic compound. A method for producing the thermoplastic resin fine particle aqueous dispersion described. 10. The carboxyl group-containing polyester resin has a gel content of 0.3% by weight or less, a weight average molecular weight (Mw) measured by GPC (gel permeation chromatography) of 3,000 to 20,000, and a number. The average molecular weight (Mn) is 1,000 to 5,000, and their ratio (Mw /
Mn) is 2 to 10, a 1/2 drop temperature (T1 / 2) in a flow tester is 80 to 140 ° C., and an acid value is 1 to 100, and a polyester resin (I), a gel content is 2% by weight or less, G
Weight average molecular weight (Mw) measured by PC method is 200,0
00 to 2,000,000, number average molecular weight (Mn) is 5,
000 to 20,000, the ratio (Mw / Mn) of these is 1
0-400, 1/2 drop temperature in flow tester (T1 /
The method for producing an aqueous dispersion of thermoplastic resin fine particles according to claim 9, wherein 2) is a resin obtained by mixing the polyester resin (II) having an acid value of 1 to 100 at 150 to 250 ° C. 11. Fine particles of the self-water-dispersible thermoplastic resin (P) colored with the colorant (C) are water-based by using the colorant (C) together with the self-water-dispersible thermoplastic resin (P). 11. A dispersion prepared by dispersing in a medium is produced.
A method for producing the thermoplastic resin fine particle aqueous dispersion according to any one of 1. 12. Separating fine particles of the self-water-dispersible thermoplastic resin (P) from the thermoplastic resin fine particle aqueous dispersion obtained by the production method according to any one of claims 1 to 11,
An electrophotographic toner containing fine particles obtained by drying.