JP5286207B2 - Method for producing developer - Google Patents

Description

  The present invention relates to a method for producing a developer for developing an electrostatic charge image and a magnetic latent image in electrophotography, electrostatic printing, and the like.

  Conventionally, as an electrophotographic toner manufacturing method, a method using an emulsification dispersion method is known. For example, a binder resin and, for example, a colorant and other additives are mixed in an aqueous medium and emulsified to obtain toner particles. be able to.

  As a method for efficiently producing an electrostatic charge image developing toner excellent in various properties such as developability, transferability, fixability, and cleaning properties, a dispersion liquid in which binder resin particles are dispersed is prepared and dispersed in the dispersion liquid. First step of forming aggregated particles to prepare an aggregated particle dispersion, and adding and mixing a finely divided dispersion obtained by dispersing fine particles into the aggregated particle dispersion to adhere the fine particles to the aggregated particles A method for producing a toner for developing an electrostatic image comprising a second step of forming particles and a third step of heating and fusing the adhered particles is disclosed (for example, see Patent Document 1). However, when manufactured by this method, when the release agent particles are used as the fine particles of the fine particle dispersion, when the atomization is performed at a high temperature, the adsorptive power of the dispersant to the release agent is reduced and the fine particles are aggregated. May occur. As a result, after aggregation, problems such as poor dispersion of the fine particles in the toner and an increase in the dispersed particle diameter occur, and the fixability deteriorates.

  In contrast, in the method for producing an electrophotographic toner containing a release agent, when the release agent is atomized at a high temperature, a polymeric nonionic surfactant is added to the release agent. There has been proposed a method for producing a toner for electrophotography in which the adsorptive power of the dispersant is improved and the occurrence of aggregation of the release agent is extremely small (see, for example, Patent Document 2).

  In this production method, first, a binder resin and, for example, a colorant and other additives are emulsified in an aqueous medium to produce resin-emulsified particles, and a release agent is added in the presence of a nonionic polymer surfactant. Disperse to produce release agent particles. Further, the resin emulsified particles and the release agent particles are aggregated and united. However, in this method, some of the fine particles are aggregated in the aggregation step, but the aggregation agent for the surfactant is insufficient, and a lot of fine powder may exist. Further, since it contains a polymer surfactant that is difficult to clean, there is a problem that in the HH environmental test, the charging property and anti-scattering property are not good as toner properties.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for producing a developer having excellent charging characteristics and a sharp particle size distribution.

The developer production method of the present invention comprises 1 ppm to 0.5% by weight of a binder resin, a coarsely granulated mixture containing a colorant, an aqueous medium, and an anionic surfactant having a molecular weight of 100 to 1000. Preparing a dispersion containing,
Allowed atomizing said toner particles by applying mechanical shearing to the dispersion to obtain a toner fine particles, and the dispersion liquid containing the toner particles, the weight ratio the anionic surfactant is from 1: 10 to 1 : in addition to salts of monovalent acidic 20, characterized in that it comprises a step of aggregating the toner particles.

  By using the method of the present invention, a developer having excellent charging characteristics and a sharp particle size distribution can be obtained.

It is a flowchart showing an example of the manufacturing method of the developing agent of this invention.

  In the method for producing a developer of the present invention, first, a coarsely granulated mixture containing a binder resin and a colorant, an aqueous medium, and an anionic surfactant having a molecular weight of 100 to 1000 are added in an amount of 1 ppm to 0.5. A dispersion containing% by weight is prepared.

  By applying mechanical shear to the obtained dispersion, the coarsely granulated mixture is atomized to obtain toner material fine particles.

  The weight ratio with respect to the anionic surfactant is 1: 1.5 to 1:30, based on the amount of the anionic surfactant, without further adding a surfactant to the dispersion containing the toner material fine particles. A certain monovalent acidic salt is added to agglomerate the toner material fine particles while lowering the pH of the fine particles to form aggregated particles. The agglomerated particles can be heated and fused to the glass transition point or higher.

  After forming the agglomerated particles, the mixture can be cooled to, for example, 5 ° C. or below the glass transition point.

  Thereafter, the toner particles are obtained, for example, by washing using a filter press and drying.

  According to the method of the present invention, a toner material containing a binder resin is mixed in an aqueous medium and subjected to mechanical shearing, whereby the material can be granulated while being finely divided. Further, by adding a predetermined amount of a monovalent acidic salt based on the amount of anionic surfactant to the dispersion containing the toner material fine particles, without further adding a surfactant, The toner can be produced without increasing the use of the activator, and a toner having a sufficient surface fixability and transferability can be obtained with little variation in surface composition.

  Further, by using such a toner, a good image can be formed.

  In the present invention, a release agent can be further added to the coarsely granulated mixture.

  According to the present invention, for example, an anionic surfactant having a molecular weight of 1000 or less of 10% or less, preferably 0.5% or less in a slurry in a wet state when a kneaded product of a polyester resin, a pigment and a release agent is wet. Is added, and the atomized product is obtained by atomization by mechanical shearing. Aggregation of fine powder, coarse particles, and mold release agent by adding monovalent acidic salt with stirring and agglomerating while lowering the pH of the atomized product without newly adding a surfactant to this slurry And a sharp particle size distribution can be obtained. In the coagulation step, the ratio of the surfactant to the monovalent acid salt in the slurry is preferably from 1: 1.5 to 30, and more preferably from 1:10 to 20. In the fusing step, a surfactant may be further added, but it can be produced without addition. The particle size can be adjusted, for example, by changing the number of revolutions of a stirring blade provided in the coagulation bath. Further, in the aggregating step, flocculation of the releasing agent can be suppressed because it can be agglomerated and fused below the melting point of the releasing agent. As a result, aggregated fused particles having a uniform particle size distribution and remarkably little occurrence of aggregation of the release agent can be obtained. Further, in a high-temperature and high-humidity environmental test with few flocculants and surfactants, it is possible to obtain aggregated fused particles that not only have good charging properties and toner scattering properties but also good cleaning properties.

  Hereinafter, the present invention will be described in more detail with reference to the drawings.

  Next, a flow chart showing an example of a developer manufacturing method according to the present invention is shown.

  As shown in the drawing, in the method for producing a developer of the present invention, first, a coarsely granulated mixture containing a binder resin, a colorant and a release agent is prepared.

  The coarsely granulated mixture is obtained, for example, by a step of melt-kneading and roughly pulverizing a mixture containing a binder resin and a colorant. Alternatively, it is obtained by granulating a mixture containing a binder resin and a colorant.

  The coarsely granulated mixture preferably has a volume average particle size of 0.05 mm to 10 mm.

  If the volume average particle size is less than 0.03 mm, strong stirring is required to disperse in the aqueous medium, and bubbles generated by stirring tend to lower the dispersion of the mixed product. The particle size is large compared to the gap provided in the shearing part of the mechanical shearing device, so the particles are clogged in the shearing part, or the composition and particle size are uneven due to the difference in energy received inside and outside the mixture There is a tendency to generate new particles.

  The coarsely granulated mixture more preferably has a volume average particle size of 0.1 mm to 5 mm.

  Next, the coarsely granulated mixture is dispersed in an aqueous medium to form a mixed liquid of the coarsely granulated mixture (Act 1).

  In the step of forming a mixture of the coarsely granulated mixture, at least one of a surfactant and a pH adjuster can be optionally added to the aqueous medium.

  By adding a surfactant, it can be easily dispersed in an aqueous medium by the action of the surfactant adsorbed on the surface of the mixture, but when added in an amount of more than 10% by weight, Granulation becomes difficult. Moreover, self-dispersibility can be improved by increasing the dissociation degree of the dissociable functional group on the surface of the mixture or increasing the polarity by adding a pH adjuster.

  Subsequently, the obtained mixed solution is subjected to mechanical shearing, and the coarsely granulated mixture is finely granulated to form fine particles (Act 2).

  According to the present invention, by performing mechanical shearing in an aqueous medium at a temperature equal to or higher than the Tg of the binder resin, the viscosity of the coarsely granulated binder resin can be ensured and finely divided and granulated. it can. According to the present invention, mechanical shearing processing temperature, processing time, mechanical shearing device, for example, the number of passes to a high-pressure atomizer, the number of revolutions of the stirring atomizer, and the ultrasonic of the ultrasonic atomizer By adjusting the strength or the like, the size of the obtained fine particles can be controlled.

  Next, the binder resin, the colorant and the release agent-containing dispersion and the aggregating agent are charged into a container for agglomeration, and these fine particles are agglomerated to a desired size to form agglomerated particles (Act 3 ).

  In order to form agglomerated particles, a flocculant can be introduced into the dispersion.

  In the step of forming the agglomerated particles, a plurality of fine particles can be agglomerated using at least one process of adding a monovalent water-soluble acidic salt and adjusting the temperature. It is possible to control the shape of the aggregated particles obtained by adjusting these processes.

  The monovalent water-soluble acid salt has an acidity of preferably 1.0 to 6.5 in pH of a solution in which 50 g is made up to 1 liter with ion-exchanged water. If the pH of a solution in which 50 g is made up to 1 liter with ion-exchanged water is 7.0 or more, when added to the slurry as a flocculant, the pH cannot be lowered, so fusion after aggregation is difficult, and the addition of acid And the particle size tends to be difficult to adjust by stirring. If it is less than 1, the aggregation behavior is relatively large, so the slurry tends to thicken, making uniform stirring difficult, and controlling the particle size distribution, pH adjustment is necessary after adding the flocculant. However, there is a tendency that non-uniform particles are generated and the process becomes complicated.

  The monovalent water-soluble acidic salt is preferably added in an amount of 1.5 to 30 parts by weight per 1 part by weight of the surfactant remaining in the slurry. If the amount is less than 1.5 parts by weight, unaggregated matter is formed, and it is difficult to obtain a uniform distribution. In order to promote fusion in the subsequent fusion process, it is necessary to add an acid. It tends to be difficult to adjust the size. If it is greater than 30, the aggregated particles tend to be coarse, and even if the rotational speed of the stirring blade is adjusted, the particle size tends to become uncontrollable, and coarse particles tend to be generated. According to this invention, the magnitude | size of the aggregate obtained can be controlled by adjusting the rotation speed of a stirring apparatus.

  This dispersion can be heated to a temperature of about +5 to + 80 ° C. with respect to the glass transition point of the binder resin, for example. According to the present invention, the size and circularity of the obtained fused particles can be controlled by adjusting the treatment temperature after the agglomeration, the treatment time, and the rotational speed of the stirring device.

  The agglomerated particles preferably have a volume average particle size of 1 to 15 μm.

  The agglomerated particles preferably have a circularity of 0.8 to 1.0.

  After forming the agglomerated particles, the dispersion is cooled to, for example, 5 ° C. or below the glass transition point (Act 4), and then washed with, for example, a filter press (Act 5) and dried (Act 6) Particles are obtained.

  As the binder resin used in the present invention, a polyester resin excellent in fixability and transparency can be used, but other resins can be used in combination. For example, polystyrene, styrene / butadiene copolymer, styrene resin such as styrene / acrylic copolymer, polyethylene, polyethylene / vinyl acetate copolymer, polyethylene / norbornene copolymer, ethylene / vinyl alcohol copolymer, etc. Examples thereof include resins, acrylic resins, phenol resins, epoxy resins, allyl phthalate resins, polyamide resins, and maleic resins. Two or more of these resins may be used in combination.

  The binder resin preferably has an acid value of 1 or more.

  Examples of the colorant used in the present invention include carbon black, organic or inorganic pigments and dyes. For example, carbon black includes acetylene black, furnace black, thermal black, channel black, ketjen black, and the like. Examples of yellow pigments include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 65, 73, 74, 81, 83, 93, 95, 97, 98, 109, 117, 120, 137, 138, 139, 147, 151, 154, 167, 173, 180, 181, 183, 185, C.I. I. Bat yellow 1, 3, 20, etc. are mentioned. These may be used alone or in combination. Examples of magenta pigments include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 146, 150, 163, 184, 185, 202, 206, 207, 209, 238, C.I. I. Pigment violet 19, C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35, etc. are mentioned. These may be used alone or in combination. Examples of cyan pigments include C.I. I. Pigment blue 2, 3, 15, 16, 17, C.I. I. Bat Blue 6, C.I. I. Acid Blue 45 and the like. These may be used alone or in combination.

  In the coarsely granulated mixture, at least one of a wax and a charge control agent can be further added.

  Examples of the wax include aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, polyolefin copolymer, polyolefin wax, microcrystalline wax, paraffin wax, and Fischer-Tropsch wax, and aliphatic hydrocarbon waxes such as oxidized polyethylene wax. Oxide of wax or block copolymer thereof, candelilla wax, carnauba wax, wood wax, jojoba wax, plant wax such as rice wax, beeswax, animal wax such as lanolin, spermaceti, ozokerite, ceresin Mineral waxes such as petrolatum, montanic ester waxes, waxes based on fatty acid esters such as castor wax, and fatty acid esters such as deoxidized carnauba wax. The other is exemplified such as those de-oxidation all. Further, saturated linear fatty acids such as palmitic acid, stearic acid, montanic acid, or long-chain alkyl carboxylic acids having a long-chain alkyl group, unsaturated fatty acids such as brassic acid, eleostearic acid, parinaric acid, stearyl alcohol , Saturated alcohols such as eicosyl alcohol, behenyl alcohol, carnauvir alcohol, seryl alcohol, melyl alcohol, or long chain alkyl alcohols having a long chain alkyl group, polyhydric alcohols such as sorbitol, linoleic acid amide, oleic acid Amide, fatty acid amide such as lauric acid amide, methylene bis stearic acid amide, ethylene biscapric acid amide, ethylene bis lauric acid amide, saturated fatty acid bis amide such as hexamethylene bis stearic acid amide, Unsaturated fatty acid amides such as lenbis oleic acid amide, hexamethylene bis oleic acid amide, N, N′-dioleyl adipic acid amide, N, N′-dioleyl sebacic acid amide, m-xylene bis stearic acid amide, Aromatic bisamides such as N, N'-distearylisophthalic amide, fatty acid metal salts such as calcium stearate, calcium laurate, zinc stearate and magnesium stearate (generally referred to as metal soap), aliphatic Hydroxyl obtained by hydrogenating waxes grafted to hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid, partially esterified products of fatty acids and polyhydric alcohols such as behenic acid monoglycerides, and vegetable oils and fats. Methyl Este Having a Group Compounds.

  As the charge control agent for controlling the triboelectric charge amount, for example, a metal-containing azo compound is used, and the metal element is preferably a complex, complex salt of iron, cobalt, chromium, or a mixture thereof. In addition, a metal-containing salicylic acid derivative compound can be used, and the metal element is preferably a complex, complex salt of zirconium, zinc, chromium, boron, or a mixture thereof.

  As a pH adjuster usable in the present invention, it is desirable to use an amine compound. Examples of amine compounds include dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, propylamine, isopropylamine, dipropylamine, butylamine, isobutylamine, sec-butylamine, monoethanolamine, diethanolamine, triethanolamine, triisopropanolamine. , Isopropanolamine, dimethylethanolamine, diethylethanolamine, N-butyldiethanolamine, N, N-dimethyl-1,3-diaminopropane, N, N-diethyl-1,3-diaminopropane and the like.

  Examples of the anionic surfactant having a molecular weight of 100 to 1000 that can be used in the present invention include sulfate ester-based, sulfonate-based, phosphate ester-based, and soap-based anionic surfactants. .

  Washing and drying is difficult because an anionic surfactant having a molecular weight exceeding 1000, for example, a sulfonate or polycarboxylate of formaldehyde condensation of an aromatic sulfonic acid having a functional group such as a hydroxyl group is difficult to wash. After that, it remains on the toner surface, which has the disadvantage of adversely affecting the charging characteristics and fixing properties.

  Further, if the addition amount of the anionic surfactant is less than 1 ppm, not only is it easy to generate coarse particles during the aggregation process, it is difficult to obtain a uniform distribution, but also during the fusing process for smoothing the surface. There is a disadvantage that coalescence of the particles forming the particle size distribution occurs and the main distribution is likely to be coarse.

  Examples of the mechanical shearing device used in the present invention include NANO3000 (Beautiful Co., Ltd.), Ultra Tarrax (manufactured by IKA Japan), TK auto homomixer (manufactured by Primix), TK pipeline homomixer (ply Mix), TK Fillmix (Primix), Claremix (M Technique), Claire SS5 (M Technique), Cavitron (Eurotech), Fine Flow Mill (Pacific Machine Works) Medialess stirrer such as Visco Mill (made by Imex), Apex Mill (made by Kotobuki Industries), Star Mill (made by Ashizawa, Finetech), DCP Super Flow (made by Japan Eirich), MP Mill (made by Inoue Manufacturing Co., Ltd.) Manufactured), spike mill (manufactured by Inoue Seisakusho), Mightymi (Manufactured by Inoue Manufacturing Co., Ltd.), SC mill (manufactured by Mitsui Mining Co., Ltd.), and the media stirrer, etc., such as.

  In the present invention, a mixture containing at least a resin and a pigment or a kneaded product is atomized using a mechanical shearing device while heating, but after atomization, the mixture may be cooled to a desired temperature once. You may set to the desired temperature which aggregates.

  In the present invention, a mixture containing a binder resin and a colorant can be kneaded to prepare a coarsely granulated mixture.

  The kneader to be used is not particularly limited as long as melt kneading is possible, and examples thereof include a single screw extruder, a twin screw extruder, a pressure kneader, a Banbury mixer, and a Brabender mixer. Specifically, FCM (made by Kobe Steel), NCM (made by Kobe Steel), LCM (made by Kobe Steel), ACM (made by Kobe Steel), KTX (made by Kobe Steel), GT (manufactured by Ikegai Co., Ltd.), PCM (manufactured by Ikegai Co., Ltd.), TEX (manufactured by Nippon Steel Works Co., Ltd.), TEM (manufactured by Toshiba Machine Co., Ltd.), ZSK (manufactured by Warner Company), and Nidex (manufactured by Mitsui Mining Company) It is done.

  In the present invention, when the fine particles are aggregated, a monovalent acidic salt among water-soluble salts is used.

  Examples of monovalent acid salts include ammonium salts such as ammonium chloride, ammonium sulfate, ammonium sulfonate, ammonium monosulfate ester, and ammonium nitrate, and hydrogen salt salts such as ammonium hydrogen sulfate, sodium hydrogen sulfate, potassium hydrogen sulfate, and monobasic ammonium phosphate. And amine salts such as dimethylaminoethanol hydrochloride, dimethylaminoethanol sulfate, diethylaminoethanol hydrochloride, ethylamine hydrochloride, diethylamine hydrochloride, triethylamine hydrochloride, and the like.

  In the present invention, in order to adjust fluidity and chargeability with respect to the toner particles, 0.01 to 20% by weight of inorganic fine particles may be added to and mixed with the toner particle surface with respect to the total weight of the toner. As such inorganic fine particles, silica, titania, alumina, strontium titanate, tin oxide and the like can be used alone or in admixture of two or more.

  The inorganic fine particles are preferably surface-treated with a hydrophobizing agent from the viewpoint of improving environmental stability. In addition to such inorganic oxides, resin fine particles having a size of 1 μm or less may be externally added to improve cleaning properties.

  As a mixer for inorganic fine particles, for example, Henschel mixer (manufactured by Mitsui Mining Co., Ltd.), super mixer (manufactured by Kawata Co., Ltd.), ribocorn (manufactured by Okawara Seisakusho Co., Ltd.), nauter mixer (manufactured by Hosokawa Micron Co., Ltd.), turbulizer (Hosokawa Micron Co., Ltd.) Co., Ltd.), cyclomixer (manufactured by Hosokawa Micron Corporation), spiral pin mixer (manufactured by Taiheiyo Kiko Co., Ltd.), and Redige mixer (manufactured by Matsubo)

  In the present invention, coarse particles and the like may be further screened. As the sieving equipment used for the sieve, Ultrasonic (manufactured by Sakae Sangyo Co., Ltd.), Gyroshifter (Tokusu Kosakusha Co., Ltd.), Vibrasonic System (manufactured by Dalton), Soniclean (manufactured by Shinto Kogyo Co., Ltd.), Turbo Screener (Manufactured by Turbo Kogyo Co., Ltd.), micro shifter (manufactured by Hadano Sangyo Co., Ltd.), circular vibrating sieve and the like.

By adopting such a configuration, a sharp particle size distribution was obtained. Furthermore, bleeding of the release agent was suppressed. As a result, the stain resistance can be improved, and an electrophotographic toner having desired charging characteristics and filming properties can be obtained, so that a good image can be provided.

  Hereinafter, the present invention will be specifically described with reference to examples.

Example 1
Production of colored fine particles 78 parts by weight of low molecular weight polyester resin, 12 parts by weight of high molecular weight polyester resin, 5 parts by weight of cyan, 4 parts by weight of ester wax, and 1 part by weight of charge control agent were mixed, and the temperature was set to 120 ° C. 2 A kneaded product was obtained by processing with a shaft kneader.

  The kneaded product was pulverized using a bantam mill to obtain a coarse granular mixture having a size of, for example, 10 μm to 100 μm. A dispersion was prepared by mixing 30 parts by weight of a coarse granular mixture, 0.3 part by weight of an anionic surfactant, 1 part by weight of an amine compound, and 68.7 parts by weight of ion-exchanged water.

  The obtained dispersion was put into NANO3000, the sample temperature was heated to 150 ° C., and subjected to mechanical shearing with one pass to obtain fine particles.

  After the treatment, the mixture was cooled to 30 ° C. to obtain colored fine particles having a volume average of 380 nm.

Production of colored agglomerated fused particles After mixing 30 parts by weight of colored fine particles and 53 parts by weight of ion exchange water, 10% while stirring at 30 ° C. in a container having a temperature adjusting mechanism and a stirring blade whose rotation speed can be adjusted. When 17 parts by weight of ammonium chloride was mixed, the pH decreased from 9 to 5, and the colored fine particles aggregated. Furthermore, stirring was continued and the mixture was heated to 80 ° C. to obtain fused particles having a volume average of 5.1 μm.

  The fused particles were washed with a centrifuge until the conductivity of the washing water reached 50 μS / cm, and dried with a vacuum dryer until the water content became 0.3 wt%. After drying, 2 parts by weight of hydrophobic silica and 0.5 parts by weight of titanium oxide were adhered to the surface of the colored particles, whereby a desired electrophotographic toner could be obtained. The volume average particle diameter of the toner for electrophotography was measured with a Coulter counter (manufactured by Beckman Coulter), and was 5.2 μm. The circularity was measured with FPIA (manufactured by Sysmex Corporation), and was 0.96. .

  5 parts by weight of the obtained toner was mixed with 95 parts by weight of a carrier to obtain a developer.

  This developer was put into a TOSHIBA TEC multifunction machine e-STUDIO 281c modified for evaluation, and fixing evaluation was performed. As a result of intentionally changing the fixing device temperature and measuring the temperature range of the fixing device capable of obtaining a good image, a temperature region (hereinafter referred to as a non-offset temperature region) capable of obtaining a good image is 70. It was found to be at ° C. The wider the non-offset region is, the more preferable it can cope with the drift of the fixing device temperature. When the temperature is 40 ° C. or lower, the probability of occurrence of a defect image tends to increase.

  Further, the developer is left for 16 hours in a high-temperature and high-humidity environment of 30 ° C. and 85%, and is left for 16 hours in a low-temperature and low-humidity environment of charge amount q / m [HH] measured by suction blow-off and 10 ° C. and 20%. The charge stability was evaluated using the charge amount q / m [LL] measured by suction blow-off. The charging stability can be evaluated by a value obtained by dividing q / m [HH] by q / m [LL], and the charging stability value of the developer was 0.74. If the value of the charging stability is 0.70 or more, a good image can be obtained regardless of the environmental atmosphere.

  Next, this developer was put into a multifunction machine e-STUDIO 281c manufactured by TOSHIBA TEC Corp., and a 100K sheet passing test was conducted at a printing rate of 10%. As a result of collecting the developer after completion of paper passing and measuring the amount of the material that contaminated the carrier surface, the amount of carrier contamination was 0.06 parts by weight. In order to obtain a satisfactory image over 100K sheets, the carrier contamination amount is desirably 0.10 parts by weight or less.

Example 2
Production of colored fine particles 78 parts by weight of low molecular weight polyester resin, 12 parts by weight of high molecular weight polyester resin, 5 parts by weight of cyan, 4 parts by weight of ester wax, and 1 part by weight of charge control agent were mixed, and the temperature was set to 120 ° C. 2 A kneaded product was obtained by processing with a shaft kneader.

  The kneaded product was pulverized using a bantam mill to obtain a coarse granular mixture having a size of, for example, 10 μm to 100 μm. A dispersion was prepared by mixing 30 parts by weight of a coarse granular mixture, 0.3 part by weight of an anionic surfactant, 1 part by weight of an amine compound, and 68.7 parts by weight of ion-exchanged water.

  The obtained dispersion was put into NANO3000, the sample temperature was heated to 150 ° C., and subjected to mechanical shearing with one pass to obtain fine particles.

  After the treatment, the mixture was cooled to 30 ° C. to obtain colored fine particles having a volume average of 380 nm.

Production of colored agglomerated fused particles After mixing 30 parts by weight of colored fine particles and 47 parts by weight of ion-exchanged water, 23 parts by weight of 10% ammonium sulfate was mixed while stirring at 30 ° C. in a container having a temperature control mechanism and a stirring blade. Then, the pH dropped from 9 to 5. Furthermore, stirring was continued and the mixture was heated to 80 ° C. to obtain fused particles having a volume average of 5.0 μm.

  The process for producing the fused particles is the same as in Example 1 except that the flocculant is changed from 17 parts by weight of 10% ammonium chloride to 23 parts by weight of 10% ammonium sulfate.

  The fused particles were washed with a centrifuge until the conductivity of the washing water reached 50 μS / cm, and dried with a vacuum dryer until the water content became 0.3 wt%. After drying, 2 parts by weight of hydrophobic silica and 0.5 parts by weight of titanium oxide were adhered to the surface of the colored particles, whereby a desired electrophotographic toner could be obtained. The volume average particle size of the toner for electrophotography was measured with a Coulter counter (manufactured by Beckman Coulter) and found to be 5.1 μm, and the circularity measured by FPIA (manufactured by Sysmex Corporation) was 0.95. It was.

  5 parts by weight of the obtained toner was mixed with 95 parts by weight of a carrier to obtain a developer.

  This developer was put into a TOSHIBA TEC multifunction machine e-STUDIO 281c modified for evaluation, and fixing evaluation was performed. As a result of measuring the temperature range of the fixing device which can intentionally change the fixing device temperature and obtain a good image, it was found that the non-offset temperature region is 68 ° C. The wider the non-offset region is, the more preferable it can cope with the drift of the fixing device temperature. When the temperature is 40 ° C. or lower, the probability of occurrence of a defect image is increased, which is not desirable.

  Further, the developer is left for 16 hours in a high-temperature and high-humidity environment of 30 ° C. and 85%, and is left for 16 hours in a low-temperature and low-humidity environment of charge amount q / m [HH] measured by suction blow-off and 10 ° C. and 20%. The charge stability was evaluated using the charge amount q / m [LL] measured by suction blow-off. When the charging stability was evaluated by a value obtained by dividing q / m [HH] by q / m [LL], the value of this developer was 0.73. As for the charging stability, if the value is 0.70 or more, a good image can be obtained regardless of the environmental atmosphere.

  Next, the developer was put into a multi-function machine e-STUDIO 281c manufactured by TOSHIBA TEC Corp., and a 100K sheet passing test was conducted at a printing rate of 10%. As a result of collecting the developer after completion of paper passing and measuring the amount of the material that contaminated the carrier surface, the amount of carrier contamination was 0.05 parts by weight. In order to obtain a satisfactory image over 100K sheets, the carrier contamination amount is desirably 0.10 parts by weight or less.

Example 3
Production of colored fine particles 78 parts by weight of low molecular weight polyester resin, 12 parts by weight of high molecular weight polyester resin, 5 parts by weight of cyan, 4 parts by weight of ester wax, and 1 part by weight of charge control agent were mixed, and the temperature was set to 120 ° C. 2 A kneaded product was obtained by processing with a shaft kneader.

  The kneaded product was pulverized using a bantam mill to obtain a coarse granular mixture having a size of, for example, 10 μm to 100 μm. A dispersion was prepared by mixing 30 parts by weight of a coarse granular mixture, 0.3 part by weight of an anionic surfactant, 1 part by weight of an amine compound, and 68.7 parts by weight of ion-exchanged water.

  The obtained dispersion was put into NANO3000, the sample temperature was heated to 150 ° C., and subjected to mechanical shearing with one pass to obtain fine particles.

  After the treatment, the mixture was cooled to 30 ° C., and colored fine particles having a volume average of 380 nm were obtained.

Production of colored agglomerated fused particles After mixing 30 parts by weight of colored fine particles and 49 parts by weight of ion-exchanged water, 21 parts by weight of 10% ammonium nitrate was mixed with stirring at 30 ° C., the pH decreased from 9 to 5. Further, stirring was continued and the mixture was heated to 80 ° C. to obtain fused particles having a volume average of 5.1 μm.

  The production process of the fused particles is the same as that of Example 1 except that the flocculant is changed from 17 parts by weight of 10% ammonium chloride to 21 parts by weight of 10% ammonium nitrate.

  The fused particles were washed with a centrifuge until the conductivity of the washing water reached 50 μS / cm, and dried with a vacuum dryer until the water content became 0.3 wt%. After drying, 2 parts by weight of hydrophobic silica and 0.5 parts by weight of titanium oxide were adhered to the surface of the colored particles, and the desired toner for electrophotography could be obtained. As a result of measuring the volume average particle diameter of the toner with a Coulter counter (manufactured by Beckman Coulter), it was 5.2 μm, and as a result of measuring the circularity with FPIA (manufactured by Sysmex Corporation), it was 0.96.

  5 parts by weight of toner was mixed with 95 parts by weight of carrier to obtain a developer. This developer was put into a TOSHIBA TEC multifunction machine e-STUDIO 281c modified for evaluation, and fixing evaluation was performed. As a result of measuring the temperature range of the fixing device which can intentionally change the fixing device temperature and obtain a good image, it was found that the non-offset temperature region is 69 ° C. The wider the non-offset region is, the more preferable it can cope with the drift of the fixing device temperature. When the temperature is 40 ° C. or lower, the probability of occurrence of a defect image is increased, which is not desirable.

  Further, the developer is left for 16 hours in a high-temperature and high-humidity environment of 30 ° C. and 85%, and is left for 16 hours in a low-temperature and low-humidity environment of charge amount q / m [HH] measured by suction blow-off and 10 ° C. and 20%. The charge stability was evaluated using the charge amount q / m [LL] measured by suction blow-off. When the value of the charging stability was determined by dividing q / m [HH] by q / m [LL], the value of this developer was 0.74. If the value of the charging stability is 0.70 or more, a good image can be obtained regardless of the environmental atmosphere.

  Next, the developer was put into a multi-function machine e-STUDIO 281c manufactured by TOSHIBA TEC Corp., and a 100K sheet passing test was performed at a printing rate of 10%. As a result of collecting the developer after completion of paper passing and measuring the amount of the material that contaminated the carrier surface, the amount of carrier contamination was 0.07 parts by weight. In order to obtain a satisfactory image over 100K sheets, the carrier contamination amount is desirably 0.10 parts by weight or less.

Comparative Example 1
Production of colored fine particles 78 parts by weight of low molecular weight polyester resin, 12 parts by weight of high molecular weight polyester resin, 5 parts by weight of cyan, 4 parts by weight of ester wax, and 1 part by weight of charge control agent were mixed, and the temperature was set to 120 ° C. 2 A kneaded product was obtained by processing with a shaft kneader. The kneaded product was pulverized using a bantam mill to obtain a coarse granular mixture having a size of, for example, 10 μm to 100 μm. A dispersion was prepared by mixing 30 parts by weight of a coarse granular mixture, 0.3 part by weight of an anionic surfactant, 1 part by weight of an amine compound, and 68.7 parts by weight of ion-exchanged water.

  The obtained dispersion was put into NANO3000, the sample temperature was heated to 150 ° C., and subjected to mechanical shearing with one pass to obtain fine particles.

  After the treatment, the mixture was cooled to 30 ° C., and colored fine particles having a volume average of 380 nm were obtained.

Production of colored agglomerated fused particles When 30 parts by weight of colored fine particles and 53 parts by weight of ion-exchanged water were mixed and then 5 parts by weight of 10% ammonium chloride was mixed while stirring at 30 ° C., the pH dropped from 9 to 8. Further, stirring was continued and the mixture was heated to 80 ° C. to obtain fused particles having a volume average of 4.5 μm.

  The fused particles were washed with a centrifuge until the conductivity of the washing water reached 50 μS / cm, and dried with a vacuum dryer until the water content became 0.3 wt%. After drying, 2 parts by weight of hydrophobic silica and 0.5 parts by weight of titanium oxide were adhered to the surface of the colored particles, whereby a desired electrophotographic toner could be obtained. As a result of measuring the volume average particle diameter of the toner with a Coulter counter (manufactured by Beckman Coulter), it was 4.5 μm, and as a result of measuring the circularity with FPIA (manufactured by Sysmex Corporation), it was 0.88.

  5 parts by weight of toner was mixed with 95 parts by weight of carrier to obtain a developer. This developer was put into a TOSHIBA TEC multifunction machine e-STUDIO 281c modified for evaluation, and fixing evaluation was performed. As a result of measuring the temperature range of the fixing device which can intentionally change the fixing device temperature and obtain a good image, it was found that the non-offset temperature region is 42 ° C. The wider the non-offset region is, the more preferable it can cope with the drift of the fixing device temperature. When the temperature is 40 ° C. or lower, the probability of occurrence of a defect image is increased, which is not desirable.

  Further, the developer is left for 16 hours in a high-temperature and high-humidity environment of 30 ° C. and 85%, and is left for 16 hours in a low-temperature and low-humidity environment of charge amount q / m [HH] measured by suction blow-off and 10 ° C. and 20%. The charge stability was evaluated using the charge amount q / m [LL] measured by suction blow-off. When the charging stability value was determined by dividing q / m [HH] by q / m [LL], the charging stability value of the developer was 0.52. If the value of the charging stability is 0.70 or more, a good image can be obtained regardless of the environmental atmosphere.

  Next, the developer was put into a multi-function machine e-STUDIO 281c manufactured by TOSHIBA TEC Corp., and a 100K sheet passing test was conducted at a printing rate of 10%. As a result of collecting the developer after completion of paper passing and measuring the amount of the material that contaminated the carrier surface, the amount of carrier contamination was 2.32 parts by weight. In order to obtain a satisfactory image over 100K sheets, the carrier contamination amount is desirably 0.10 parts by weight or less.

  The production process of the fused particles is the same as that of Example 1 except that the amount of 10% ammonium chloride as the flocculant is changed from 17 parts by weight to 5 parts by weight. Thus, when the weight ratio of the monovalent acidic salt to the anionic surfactant is less than 1.5, the aggregation is insufficient and the average particle size becomes small, the circularity, the non-offset temperature region, and the charging stability. It can be seen that both decrease and the amount of carrier contamination increases.

Comparative Example 2
Production of colored fine particles 78 parts by weight of low molecular weight polyester resin, 12 parts by weight of high molecular weight polyester resin, 5 parts by weight of cyan, 4 parts by weight of ester wax, and 1 part by weight of charge control agent were mixed, and the temperature was set to 120 ° C. 2 A kneaded product was obtained by processing with a shaft kneader. The kneaded product was pulverized using a bantam mill to obtain a coarse granular mixture having a size of, for example, 10 μm to 100 μm. A dispersion was prepared by mixing 30 parts by weight of a coarse granular mixture, 0.3 part by weight of an anionic surfactant, 1 part by weight of an amine compound, and 68.7 parts by weight of ion-exchanged water.

  The obtained dispersion was put into NANO3000, the sample temperature was heated to 150 ° C., and subjected to mechanical shearing with one pass to obtain fine particles.

  After the treatment, the mixture was cooled to 30 ° C., and colored fine particles having a volume average of 380 nm were obtained.

Production of colored agglomerated fused particles When 30 parts by weight of colored fine particles and 53 parts by weight of ion-exchanged water were mixed and then 50 parts by weight of 10% ammonium chloride was mixed with stirring at 30 ° C., the pH dropped from 9 to 4. Furthermore, stirring was continued and the mixture was heated to 80 ° C. to obtain fused particles having a volume average of 14 μm.

  The fused particles were washed with a centrifuge until the conductivity of the washing water reached 50 μS / cm, and dried with a vacuum dryer until the water content became 0.3 wt%. After drying, 2 parts by weight of hydrophobic silica and 0.5 parts by weight of titanium oxide were adhered to the surface of the colored particles, whereby a desired electrophotographic toner could be obtained. The volume average particle diameter of the electrophotographic toner was measured with a Coulter counter (manufactured by Beckman Coulter). As a result, it was 14 μm, and the circularity was measured by FPIA (manufactured by Sysmex Corporation), and was 0.92.

  5 parts by weight of toner was mixed with 95 parts by weight of carrier to obtain a developer. This developer was put into a TOSHIBA TEC multifunction machine e-STUDIO 281c modified for evaluation, and fixing evaluation was performed. As a result of measuring the temperature range of the fixing device which can intentionally change the fixing device temperature and obtain a good image, it was found that the non-offset temperature region is 45 ° C. The wider the non-offset region is, the more preferable it can cope with the drift of the fixing device temperature. When the temperature is 40 ° C. or lower, the probability of occurrence of a defect image is increased, which is not desirable.

  The developer is allowed to stand for 16 hours in a high-temperature and high-humidity environment of 30 ° C. and 85%, and is left for 16 hours in a low-temperature and low-humidity environment of 10 ° C. and 20% with a charge amount q / m [HH] measured by suction blow-off. The charge stability was evaluated using the charge amount q / m [LL] measured by suction blow-off. The charging stability can be obtained by dividing q / m [HH] by q / m [LL], and the charging stability value of this developer was 0.74. If the value of the charging stability is 0.70 or more, a good image can be obtained regardless of the environmental atmosphere.

  Next, the developer was put into a multi-function machine e-STUDIO 281c manufactured by TOSHIBA TEC Corp., and a 100K sheet passing test was conducted at a printing rate of 10%. As a result of collecting the developer after completion of paper passing and measuring the amount of the material that contaminated the carrier surface, the amount of carrier contamination was 0.25 parts by weight. In order to obtain a satisfactory image over 100K sheets, the carrier contamination amount is desirably 0.10 parts by weight or less.

  The production process of the fused particles is the same as that of Example 1 except that the amount of 10% ammonium chloride as the flocculant is changed from 17 parts by weight to 50 parts by weight. When the weight ratio of the monovalent acidic salt to the anionic surfactant exceeds 30, the agglomeration proceeds too much, the particle size increases, the circularity and the non-offset region decrease, and the amount of carrier contamination increases. .

Comparative Example 3
Production of colored fine particles 78 parts by weight of low molecular weight polyester resin, 12 parts by weight of high molecular weight polyester resin, 5 parts by weight of cyan, 4 parts by weight of ester wax, and 1 part by weight of charge control agent were mixed, and the temperature was set to 120 ° C. 2 A kneaded product was obtained by processing with a shaft kneader. The kneaded product was pulverized using a bantam mill to obtain a coarse granular mixture having a size of, for example, 10 μm to 100 μm. 30 parts by weight of a coarse granular mixture, 4 parts by weight of an anionic surfactant, 1 part by weight of an amine compound, and 65 parts by weight of ion-exchanged water are added to NANO 3000, the sample temperature is heated to 150 ° C., and fine particles are passed once. The compound was obtained. After the treatment, the mixture was cooled to 30 ° C., and colored fine particles having a volume average of 210 nm were obtained.

Production of colored agglomerated fused particles After mixing 30 parts by weight of colored fine particles and 53 parts by weight of ion-exchanged water, 17 parts by weight of 10% ammonium chloride was mixed with stirring at 30 ° C., and the pH dropped from 9 to 5. Further, stirring was continued and the mixture was heated to 80 ° C. to obtain fused particles having a volume average of 3.2 μm.

  The fused particles were washed with a centrifuge until the conductivity of the washing water reached 50 μS / cm, and dried with a vacuum dryer until the water content became 0.3 wt%. After drying, 2 parts by weight of hydrophobic silica and 0.5 parts by weight of titanium oxide were adhered to the surface of the colored particles, whereby a desired electrophotographic toner could be obtained. The volume average particle size of the toner for electrophotography was measured with a Coulter counter (manufactured by Beckman Coulter) and found to be 3.2 μm, and the circularity measured by FPIA (manufactured by Sysmex Corporation) was 0.71. It was.

  5 parts by weight of toner was mixed with 95 parts by weight of carrier to obtain a developer. This developer was put into a TOSHIBA TEC multifunction machine e-STUDIO 281c modified for evaluation, and fixing evaluation was performed. As a result of intentionally changing the fixing device temperature and measuring the temperature range of the fixing device capable of obtaining a good image, it was found that the non-offset temperature region was 31 ° C. The wider the non-offset region is, the more preferable it can cope with the drift of the fixing device temperature. When the temperature is 40 ° C. or lower, the probability of occurrence of a defect image is increased, which is not desirable.

  The developer is allowed to stand for 16 hours in a high-temperature and high-humidity environment at 30 ° C. and 85%, and is left for 16 hours in a low-temperature and low-humidity environment at 10 ° C. and 20% with a charge amount q / m [HH] measured by suction blow-off. Then, the charging stability was evaluated using the charge amount q / m [LL] measured by suction blow-off. When the charging stability was determined by dividing q / m [HH] by q / m [LL], the charging stability value of the developer was 0.21. If the value of the charging stability is 0.70 or more, a good image can be obtained regardless of the environmental atmosphere.

  Next, the developer was put into a multi-function machine e-STUDIO 281c manufactured by TOSHIBA TEC Corp., and a 100K sheet passing test was conducted at a printing rate of 10%. As a result of collecting the developer after completion of paper passing and measuring the amount of the material that contaminated the carrier surface, the amount of carrier contamination was 1.38 parts by weight. In order to obtain a satisfactory image over 100K sheets, the carrier contamination amount is desirably 0.10 parts by weight or less.

  In addition, the manufacturing process of this colored fine particle is the same as that of Example 1 except changing the addition amount of an anionic surfactant from 0.3 weight part to 4 weight part. When the amount of the anionic surfactant in the dispersion exceeds 0.5% by weight and the weight ratio of the monovalent acidic salt to the anionic surfactant is less than 1.5, the aggregation is insufficient and the particle size Becomes very small. Further, it can be seen that the circularity and the non-offset region are lowered, and the amount of carrier contamination is increased.

Comparative Example 4
Production of colored fine particles 78 parts by weight of low molecular weight polyester resin, 12 parts by weight of high molecular weight polyester resin, 5 parts by weight of cyan, 4 parts by weight of ester wax, and 1 part by weight of charge control agent were mixed, and the temperature was set to 120 ° C. 2 A kneaded product was obtained by processing with a shaft kneader.

  The kneaded product was pulverized using a bantam mill to obtain a coarse granular mixture having a size of, for example, 10 μm to 100 μm. A dispersion was prepared by mixing 30 parts by weight of a coarse granular mixture, 0.3 part by weight of an anionic surfactant, 1 part by weight of an amine compound, and 68.7 parts by weight of ion-exchanged water.

  The obtained dispersion was put into NANO3000, the sample temperature was heated to 150 ° C., and a finely divided product was obtained by one pass. After the treatment, the mixture was cooled to 30 ° C., and colored fine particles having a volume average of 380 nm were obtained.

Production of colored agglomerated fused particles After mixing 30 parts by weight of colored fine particles and 53 parts by weight of ion-exchanged water, 50 parts by weight of 10% zinc chloride was mixed with stirring at 30 ° C., and the pH dropped from 9 to 4. Furthermore, when the stirring was continued and heating to 80 ° C., a lump was fixed to the bottom of the flask, and particles usable as a toner were not obtained.

  The production process of the colored aggregated fused particles is the same as that of Example 1 except that zinc chloride, which is a divalent acid salt, is used instead of ammonium chloride, which is a monovalent acid salt.

Comparative Example 5
Production of colored fine particles 78 parts by weight of low molecular weight polyester resin, 12 parts by weight of high molecular weight polyester resin, 5 parts by weight of cyan, 4 parts by weight of ester wax, and 1 part by weight of charge control agent were mixed, and the temperature was set to 120 ° C. 2 A kneaded product was obtained by processing with a shaft kneader.

  The kneaded product was pulverized using a bantam mill to obtain a coarse granular mixture having a size of, for example, 10 μm to 100 μm. A dispersion was prepared by mixing 30 parts by weight of a coarse granular mixture, 0.3 part by weight of an anionic surfactant, 1 part by weight of an amine compound, and 68.7 parts by weight of ion-exchanged water.

  The obtained dispersion was put into NANO3000, the sample temperature was heated to 150 ° C., and a finely divided product was obtained by one pass. After the treatment, the mixture was cooled to 30 ° C., and colored fine particles having a volume average of 380 nm were obtained.

Production of colored agglomerated fused particles After mixing 30 parts by weight of colored fine particles and 53 parts by weight of ion exchange water, 50 parts by weight of 10% aluminum chloride was mixed with stirring at 30 ° C., and the pH dropped from 9 to 3. Furthermore, when the stirring was continued and heating to 80 ° C., a lump was fixed to the bottom of the flask, and particles usable as a toner were not obtained.

  The production process of the colored aggregated fusion particles is the same as that of Example 1 except that aluminum chloride, which is a trivalent acid salt, is used instead of ammonium chloride, which is a monovalent acid salt.

Comparative Example 6
After mixing 78 parts by weight of low molecular weight polyester resin, 12 parts by weight of high molecular weight polyester resin, 5 parts by weight of cyan, 4 parts by weight of ester wax, and 1 part by weight of charge control agent, a biaxial kneader set at a temperature of 120 ° C. And kneaded product was obtained.

  The kneaded product was pulverized using a bantam mill to obtain a coarse granular mixture having a size of, for example, 10 μm to 100 μm. A dispersion was prepared by mixing 30 parts by weight of a coarse granular mixture, 4 parts by weight of an anionic surfactant, 1 part by weight of an amine compound, and 65 parts by weight of ion-exchanged water.

  The obtained dispersion was put into NANO3000, the sample temperature was heated to 150 ° C., and a finely divided product was obtained by one pass. After the treatment, the mixture was cooled to 30 ° C., and colored fine particles having a volume average of 210 nm were obtained.

Production of colored agglomerated fused particles After mixing 30 parts by weight of colored fine particles and 53 parts by weight of ion-exchanged water, 50 parts by weight of 10% zinc chloride was mixed with stirring at 30 ° C., and the pH dropped from 9 to 4. Furthermore, when stirring was continued and heating was performed to 80 ° C., a lump was fixed to the bottom of the flask, and particles having a broad distribution including unaggregated particles were obtained, and particles usable as a toner were not obtained.

  In addition, the manufacturing process of the colored aggregated fusion particles uses zinc chloride, which is a divalent acid salt, instead of ammonium chloride, which is a monovalent acid salt, as in Comparative Example 4, and in addition, anionic The addition amount of the surfactant was increased from 0.3 parts by weight to 4 parts by weight.

  As is clear from Comparative Examples 4 to 6, if divalent and trivalent acid salts are used when agglomerating colored fine particles containing a toner material, the toner particles cannot be formed. Further, when the amount of the surfactant was increased as in Comparative Example 6, aggregation was not possible at all.

The results obtained by the above Examples and Comparative Examples are shown in Tables 1-1 and 1-2 below.

JP-A-10-26842 JP 2007-147699 A

Claims (5)

Preparing a dispersion comprising 1 ppm to 0.5 wt% of a binder resin, a coarsely granulated mixture containing a colorant, an aqueous medium, and an anionic surfactant having a molecular weight of 100 to 1000;
Allowed atomizing said toner particles by applying mechanical shearing to the dispersion to obtain a toner fine particles, and the dispersion liquid containing the toner particles, the weight ratio the anionic surfactant is from 1: 10 to 1 : method for producing a developing agent characterized by comprising the step of adding a salt of a monovalent acid which is 20 to aggregate the toner particles. Salts of acidic said monovalent ammonium chloride, ammonium sulfate, ammonium sulfonate, ammonium monosulfates, ammonium nitrate, ammonium hydrogen sulfate, sodium hydrogen sulfate, potassium hydrogen sulfate, primary phosphate, ammonium, dimethylaminoethanol hydrochloride, dimethylaminoethyl The method according to claim 1, wherein the method is at least one selected from the group consisting of ethanol sulfate, diethylaminoethanol hydrochloride, ethylamine hydrochloride, diethylamine hydrochloride, and triethylamine hydrochloride . The method according to claim 1 , wherein the binder resin is a polyester resin . The coarsely granulated mixture further method according to any one of claims 1 to 3, characterized that you contains a release agent. The aggregation step A method according to any one of claims 1 Ru made without further addition of surfactant 4.

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