JP2010276749A - Method for manufacturing toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing toner excellent in both fixability and blocking resistance. <P>SOLUTION: The method includes: (A) a mixing step of acquiring a mixture by mixing, in an aqueous medium, a first resin having acid radical, a basic material, a colorant and a release agent together; (B) an emulsification step of acquiring an emulsified product by applying a shear force to the mixture, while heating it at a temperature higher by 10°C or more than a softening temperature (Tm1) of the first resin; (C) a cooling step of acquiring complex fine particles including the first resin, the release agent and the colorant by cooling the emulsified product to a temperature equal to or below a glass transition temperature (Tg1) of the first resin, while applying a shear force thereto; (D) a thermal conglobation step of acquiring conglobated complex particles by heating the complex particles to a temperature equal to or higher than Tg1 of the first resin; (E) an aggregation step of forming aggregated particles by aggregating the conglobated complex particles in the aqueous medium at a temperature equal to or below Tg1 of the first resin by an additive or the like; and (F) a fusing step of acquiring toner particles by heating the aggregated particles to the temperature equal to or higher than Tg1 of the first resin to fuse them. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a toner manufacturing method that can be used in an electrophotographic apparatus using an electrophotographic process such as a copying machine, a printer, and a facsimile machine.

  Conventionally, electrostatic printing methods, electrophotographic methods, and the like have been prominent as methods for forming a visible image by developing an electric latent image with a developer (see Patent Documents 1, 2, and 3).

  In recent years, there has been a demand for energy saving in electrophotographic image forming apparatuses and printers due to requests for global warming prevention measures. To meet these demands, the amount of heat required for image fixing is reduced. There is a need for technology to reduce this.

  Generally, in order to improve the low-temperature fixability, the glass transition temperature of the toner may be lowered. However, lowering the glass transition point (Tg) of the toner is effective as a means for improving the low-temperature fixability. However, a toner having a low glass transition point (Tg) can be kept in a stationary state during storage or transportation. In some cases, the toner may be blocked due to aggregation.

  In order to solve such problems, a toner having a core / shell structure in which a resin having a low softening temperature and a low glass transition point is coated with a resin having a high softening temperature and a high glass transition point has been proposed ( (See Patent Document 4).

  On the other hand, with the rapid spread of the current digitization technology, there is an increasing demand for higher image quality in output such as printing and copying for users in ordinary homes, offices, and publishing areas. In order to meet the demand for higher image quality, particularly in the toner used for electrophotography, it is one of technically important approaches to improve the resolution by reducing the particle diameter of the toner. At present, it is possible to reduce the weight average particle diameter of the toner particles to an area of 5 μm. However, in order to produce a toner having a weight average particle diameter of 6 μm or less while sufficiently controlling the particle size distribution, conventionally used kneading and pulverizing methods are difficult in terms of production energy and cost. Therefore, at present, a toner manufacturing method using a so-called chemical manufacturing method such as a suspension polymerization method, a dissolution suspension method, and an emulsion aggregation method in which the particle size distribution and particle size of the toner can be easily adjusted has been adopted. Among them, the emulsion aggregation method is attracting attention because it can intentionally control the shape and dispersibility of particles.

  The emulsion aggregation method is generally used to prepare a resin dispersion by emulsion polymerization or the like, while preparing a colorant dispersion in which a colorant is dispersed in a solvent and mixing them to form aggregate particles corresponding to the toner particle diameter. The toner particles are fused and united by heating to form toner particles. More specifically, a resin dispersion obtained by emulsion polymerization using an ionic surfactant is mixed with a dispersion of a pigment dispersed with an ionic surfactant, and agglomeration is caused by adding a flocculant. To form aggregate particles having a toner particle size, stop the growth of the particle size with a large amount of ionic surfactant, and then heat to a temperature higher than the glass transition point (Tg) of the resin. Fuse and unite. In this manufacturing method, the toner particle shape can be controlled from an indeterminate shape to a spherical shape by selecting a heating temperature condition (see Patent Documents 5, 6 and 7).

  These manufacturing methods have the characteristics that the particle size distribution can be sharpened and the particle size can be reduced, and in particular, in color image formation, they are studied as a promising method for realizing high-definition images. .

  However, in the conventional emulsion aggregation method, the binder resin particles, the colorant particles and the release agent particles are separately prepared, and these are aggregated. Aggregation is likely to occur, the dispersion of each component in the toner tends to be non-uniform, and there may be problems such as uneven composition among the toner particles.

  Furthermore, there is a problem that a large amount of a surfactant is unavoidable for stabilizing the particles during toner preparation, and the surfactant remains in the toner at the end of the reaction. If the surfactant remains in the toner particles, the toner is made low in charge and low in resistance, and particularly has a great adverse effect under high temperature and high humidity, so that stable developability and transferability of the toner may not be achieved. Therefore, the advantage that the particle size distribution can be sharpened and a high-definition image can be realized by reducing the particle size is lost. Further, due to contamination of the toner particle surface, fluidity, storage stability and the like are lowered, leading to a decrease in reliability. Therefore, it is required to keep the surfactant as little as possible on the toner particles. Moreover, there is also a problem that the amount of washing water becomes enormous if the remaining amount is reduced as much as possible.

  Therefore, in order to improve the dispersibility of the colorant and / or mold release agent in the resin and reduce the amount of the surfactant used, as a result of our extensive studies, the resin, the colorant and / or the mold release agent It was found that by coagulating and fusing the rod-like composite fine particle dispersion emulsified simultaneously, toner particles with improved dispersibility of the colorant and release agent and reduced residual amount of surfactant can be obtained.

  However, since the shape of the composite fine particles prepared by this emulsification technique is rod-shaped, it has been found that when the core / shell toner is prepared using the composite fine particles as the core particles, a large amount of shell is required in the total amount of toner. When the amount of the shell is increased, the blocking resistance is improved, but the fixing property is deteriorated. As described above, it is difficult to achieve both the fixing property and the blocking resistance in the toner production method using the emulsion aggregation method.

US Pat. No. 2,297,691 Japanese Patent Publication No.42-23910 Japanese Patent Publication No.43-24748 JP 2006-235027 A Japanese Patent Laid-Open No. 63-282275 JP-A-6-250439 JP 2002-351140 A

  The present invention has been made for the purpose of improving the above problems. That is, the present invention provides a toner manufacturing method that is excellent in both fixing property and blocking resistance in a toner manufacturing method using an emulsion aggregation method.

  As a result of intensive studies to solve the above problems of the prior art, the present inventors have found that the above object can be achieved by the following contents.

(1) Mixing step of obtaining a mixture by mixing (A) at least (A) a first resin having an acid group, a basic substance, a surfactant, a colorant and / or a release agent in an aqueous medium (B) An emulsification step of obtaining an emulsion by applying a shearing force while heating the mixture to a temperature higher by 10 ° C. or more than the softening temperature (Tm1) of the first resin having an acid group;
(C) While applying a shearing force to the emulsion at a temperature not higher than the glass transition temperature (Tg1) of the first resin having the acid group, at a cooling rate of 0.5 ° C./min to 10 ° C./min. A cooling step of cooling to obtain composite fine particles containing the first resin having the acid group, the release agent and / or the colorant;
(D) a thermal spheronization step in which the composite fine particles are heated to a temperature equal to or higher than the glass transition temperature (Tg1) of the first resin having an acid group to obtain spherical composite fine particles;
(E) an aggregation step of aggregating at least the spheroidized composite fine particles with an aggregating agent in the aqueous medium at a temperature equal to or lower than the glass transition temperature (Tg1) of the first resin having an acid group; ,
(F) A toner having each step of a fusion step in which the aggregated particles are heated to a temperature equal to or higher than the glass transition temperature (Tg1) of the first resin having an acid group and fused to obtain toner particles. Manufacturing method.

(2) In the aggregation step, the spheroidized composite fine particles are aggregated with a flocculant below the glass transition temperature (Tg1) of the first resin having an acid group in the aqueous medium to form core aggregated particles. Primary agglomeration step,
Second order to obtain core / shell aggregated particles by mixing the second resin fine particles at a temperature lower than the glass transition point (Tg1) of the first resin and attaching the second resin fine particles to the core aggregated particles. A relationship between the glass transition point (Tg1) of the first resin having the acid group and the glass transition point (Tg2) of the second resin is at least Tg1 <Tg2 including at least an aggregation step. The method for producing a toner according to 1).
(3) The method for producing a toner according to (2), wherein a ratio of the second resin to the first resin having an acid group is 3% by weight or more and 30% by weight or less.
(4) The toner according to any one of (2) to (3), wherein the softening temperature (Tm1) of the first resin having an acid group is 70 ° C. or higher and 110 ° C. or lower. Production method.
(5) The method for producing a toner according to any one of (2) to (4), wherein the glass transition point (Tg2) of the second resin is 60 ° C. or higher and 80 ° C. or lower.
(6) The toner according to any one of (2) to (5), wherein a median diameter based on volume distribution of the second resin fine particles is 0.05 μm or more and 0.3 μm or less. Production method.
(7) The toner according to any one of (1) to (6), wherein the 50% particle size based on volume distribution of the composite particles is 0.02 μm or more and 1.00 μm or less. Manufacturing method.
(8) The toner according to any one of (1) to (7), wherein an average ratio of major axis / minor axis of the spheroidized composite fine particles is 1.0 or more and 2.0 or less. Production method.
(9) The method for producing a toner according to any one of (1) to (8), wherein the resin having an acid group is a polyester resin.
(10) The method for producing a toner according to any one of (1) to (9), wherein the basic substance is an amine.
(11) A toner obtainable by the method for producing a toner according to any one of (1) to (10).

  According to the present invention, a toner excellent in fixing property and anti-blocking property can be produced in a toner production method using an emulsion aggregation method.

  The toner production method of the present invention includes a mixing step of mixing a first resin having an acid group, a basic substance, a surfactant, a colorant and / or a release agent in an aqueous medium to obtain a mixture; An emulsification step of applying an shearing force while heating the mixture to a temperature higher by 10 ° C. or higher than the softening temperature (Tm1) of the first resin having the acid group to obtain an emulsion; the emulsion having the acid group The first resin having the acid group by cooling at a cooling rate of 0.5 ° C./min to 10 ° C./min while applying a shearing force to a temperature not higher than the glass transition temperature (Tg1) of the first resin. Cooling step for obtaining composite fine particles containing the release agent and / or the colorant; heating the composite particles to a temperature equal to or higher than the glass transition temperature (Tg1) of the first resin having the acid group. Thermal spheronization step to obtain spheroidized composite particles; at least said spheronization An aggregating step of aggregating the fine particles with an aggregating agent at a temperature equal to or lower than the glass transition temperature (Tg1) of the first resin having an acid group in the aqueous medium to form the agglomerated particles; and A fusing step of heating to a temperature equal to or higher than the glass transition temperature (Tg1) of the first resin having a group to obtain toner particles by fusing.

  Further, in the agglomeration step, at least the spheroidized composite fine particles are agglomerated with an aggregating agent at a temperature equal to or lower than the glass transition temperature (Tg1) of the first resin having an acid group in the aqueous medium to form core agglomerated particles. In the primary aggregation step, the second resin fine particles and the aggregating agent are mixed at a temperature lower than the glass transition point (Tg1) of the first resin, and the second resin fine particles are adhered to the core aggregated particles. The relationship between the glass transition point (Tg1) of the first resin having the acid group and the glass transition point (Tg2) of the second resin is at least a second aggregation step for obtaining shell aggregated particles, and Tg1 <Tg2 It is characterized by being. By using this method, in the toner production method using the emulsion aggregation method, a method for producing a toner excellent in fixing property and anti-blocking property has been found.

  Below, this invention is demonstrated in detail for every process.

(A) Mixing step Specifically, first, an aqueous medium, a first resin having an acid group, a basic substance, a colorant and / or a release agent, and a surfactant are placed in a container that can be sealed and pressurized. Mix the mixture. These mixing methods are not particularly limited, and may be added and mixed at the same time, or may be added and mixed one by one. In this case, the order of addition is not particularly limited, but the dispersion of the colorant is not limited. From the viewpoint of the property and uniformity of mixing, it is preferable to sequentially add and mix a binder resin, a colorant and / or a release agent into an aqueous medium having a surfactant and a basic substance. Colorants and / or mold release agents may be added as an aqueous dispersion.

  In the method for producing toner particles of the present invention, a charge control agent can be further used as a constituent material of the toner particles. In this case, charging may be performed in the mixing process or may be performed in the aggregation process.

(First resin having an acid group)
As a 1st resin which has an acid group used for this invention, it is resin which has a carboxyl group or a sulfonic acid group in at least any one of the terminal and side chain of a molecule | numerator. As a resin suitable when the aqueous dispersion of resin fine particles of the present invention is used in producing a toner, a (meth) acrylic resin, a styrene- (meth) acrylic copolymer resin or a polyester resin is preferable. Among these, polyesters having a rigid aromatic ring in the main chain have lower molecular weight than vinyl polymers because they are more flexible than vinyl polymers such as styrene-acrylic copolymers. Even so, equivalent mechanical strength can be imparted. Therefore, polyester is preferable as a resin suitable for low-temperature fixability.

  The softening temperature (Tm) of the resin is measured using a flow tester (CFT-500D: manufactured by Shimadzu Corporation). Specifically, 1.5 g of a sample to be measured is weighed, a die having a height of 1.0 mm and a diameter of 1.0 mm is used, a heating rate of 4.0 ° C./min, a preheating time of 300 seconds, a load of 5 kg, Measurement is performed under conditions of a measurement temperature range of 60 to 200 ° C. The temperature at which 1/2 of the above sample flows out is defined as the softening temperature (Tm).

  Moreover, the said glass transition temperature (Tg) is a physical-property value measured based on JISK7121, and means the midpoint glass transition temperature described in this specification.

  The glass transition point (Tg1) of the first resin having an acid group is preferably 30 ° C. or higher and 70 ° C. or lower, and more preferably 40 ° C. or higher and 60 ° C. or lower. When Tg1 is less than 30 ° C., the strength of the entire toner particles is lowered, and the transferability is deteriorated and toner conveyance unevenness is likely to occur during the durability test. Further, the toner particles are likely to aggregate in a high-temperature and high-humidity environment, resulting in a problem that uneven conveyance is likely to occur. If it is higher than 60 ° C., the glossiness of the image when fixing at a low temperature is deteriorated.

  The softening temperature (Tm1) of the first resin having an acid group is preferably 70 ° C. or higher and 110 ° C. or lower, more preferably 70 ° C. or higher and 100 ° C. or lower, and most preferably 80 ° C. or higher and 100 ° C. or lower. . When Tm1 is less than 70 ° C., the blocking resistance is weak, and even when a wax is contained, high offset resistance cannot be expected. Further, at a high temperature, the toner melt component becomes noticeable at the time of fixing, and the surface smoothness is impaired. When it is higher than 110 ° C., the fixing property is deteriorated.

  The mass ratio of the first resin having an acid group to the aqueous medium (the mass of the resin fine particles / the mass of the aqueous medium) is preferably 0.20 or more and less than 0.60. More preferably, it is 0.25 or more and less than 0.60.

  The higher the mass ratio of the resin to the aqueous medium, the smaller the particle size of the resin fine particles, and the surfactant concentration can be reduced. However, since the viscosity of the aqueous dispersion increases, it is difficult to produce a composite fine particle dispersion above 0.60.

(Aqueous medium)
As said aqueous medium, water, such as distilled water and ion-exchange water, is preferable, for example. A hydrophilic solvent that is easily miscible with water, such as methanol or acetone, can be added as long as it does not adversely affect the emulsification, but it is preferably 100% by mass of water from the viewpoint of environmental load.

(Basic substance)
If the resin having an acid group is atomized as it is in an aqueous medium, the pH becomes 3 to 4 and may be too biased toward the acidic side. For example, when a crystalline polyester resin is present, the crystalline polyester resin is hydrolyzed. May end up. However, the presence of the basic substance can make it difficult for the aqueous dispersion to move to the acidic side during emulsification, so even when the resin having an acid group is atomized in the aqueous medium, An aqueous dispersion of resin fine particles can be obtained without hydrolysis of the resin.

  Examples of the basic substance include inorganic bases such as ammonia, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, and organic bases such as dimethylamine, diethylamine, and triethylamine. . Among these, from the viewpoint of not causing hydrolysis, organic bases such as dimethylamine and triethylamine which are weak bases are preferable.

  The amount of the basic substance added is preferably adjusted as appropriate so that the pH during emulsification is adjusted to around neutrality. The basic substance tends to reduce the particle size of the resin fine particles as the amount of the basic substance increases. Moreover, when using a strong base as a basic substance, it is necessary to limit the addition amount so as not to cause hydrolysis.

(Surfactant)
Examples of the surfactant include anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap; cationic surfactants such as amine salt type and quaternary ammonium salt type; polyethylene Nonionic surfactants such as glycol-based, alkylphenol ethylene oxide adduct-based, polyhydric alcohol-based and the like can be mentioned. Among these, it is preferable to use at least one of a nonionic surfactant and an anionic surfactant. The said surfactant may be used individually by 1 type, may use 2 or more types together, and may be used together with a nonionic surfactant and an anionic surfactant. The concentration of the surfactant in the aqueous medium is preferably 0.5 to 5% by mass.

(Coloring agent)
Preferred examples of the colorant include the following pigments or dyes.

  As the cyan pigments or dyes, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds, and the like can be used. Specifically, C.I. I. Pigment blue 1, C.I. I. Pigment blue 7, C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 1, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 15: 4, C.I. I. Pigment blue 60, C.I. I. Pigment blue 62, C.I. I. And CI Pigment Blue 66.

  As the magenta pigments or dyes, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, perylene compounds, and the like are used.

  Specifically, C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment violet 19, C.I. I. Pigment red 23, C.I. I. Pigment red 48: 2, C.I. I. Pigment red 48: 3, C.I. I. Pigment red 48: 4, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 81: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 144, C.I. I. Pigment red 146, C.I. I. Pigment red 150, C.I. I. Pigment red 166, C.I. I. Pigment red 169, C.I. I. Pigment red 177, C.I. I. Pigment red 184, C.I. I. Pigment red 185, C.I. I. Pigment red 202, C.I. I. Pigment red 206, C.I. I. Pigment red 220, C.I. I. Pigment red 221, C.I. I. And CI Pigment Red 254.

  As yellow pigments or dyes, compounds represented by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, allylamide compounds, and the like are used. Specifically, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 62, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 83, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 95, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 109, C.I. I. Pigment yellow 110, C.I. I. Pigment yellow 111, C.I. I. Pigment yellow 120, C.I. I. Pigment yellow 127, C.I. I. Pigment yellow 128, C.I. I. Pigment yellow 129, C.I. I. Pigment yellow 147, C.I. I. Pigment yellow 151, C.I. I. Pigment yellow 154, C.I. I. Pigment yellow 155, C.I. I. Pigment yellow 168, C.I. I. Pigment yellow 174, C.I. I. Pigment yellow 175, C.I. I. Pigment yellow 176, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 181, C.I. I. Pigment yellow 191, C.I. I. And CI Pigment Yellow 194.

  As the black colorant, carbon black or a color toned to black using the yellow / magenta / cyan colorant can be used.

  These colorants can be used alone or in combination.

  The colorant is selected from the viewpoints of hue angle, saturation, brightness, light resistance, OHP transparency, and dispersibility in the toner.

  The colorant is preferably used by adding 1 to 30 parts by mass with respect to 100 parts by mass of the binder resin.

  In the present invention, the mixing form of the colorant is not particularly limited, and may be mixed as a dry powder. An aqueous dispersion previously dispersed in an aqueous medium, or an aqueous presscake (both paste and slurry). May be mixed). Among these, from the viewpoint of dispersibility of the colorant, it is more preferable to mix in the form of an aqueous dispersion or an aqueous press cake that has been dispersed in an aqueous medium in advance.

  The aqueous dispersion of the colorant as described above can be prepared by the following known methods, but is not limited to these methods. For example, it can be prepared by mixing a colorant, an aqueous medium, and a dispersant using a known stirrer, emulsifier, disperser, or the like. As the dispersant used here, for example, a known one such as a surfactant or a polymer dispersant may be used, or one newly synthesized for the present invention may be used. Any of the dispersants can be removed in the toner cleaning step described later. However, from the viewpoint of cleaning efficiency, the surfactant described later is preferable, and among the surfactants, anionic surfactants and nonionic surfactants are preferred. Etc. are preferable. The amount of the dispersant to be mixed is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the colorant, and more preferably 2 to 10 parts by mass from the viewpoint of achieving both dispersion stability and toner cleaning efficiency. The colorant content in the colorant aqueous dispersion is not particularly limited, but is preferably about 1 to 30% by mass with respect to the total mass of the colorant aqueous dispersion. The particle size of the colorant dispersed in the aqueous medium is preferably 90% cumulative particle size (d90) of 2 μm or less, more preferably 50 μm, from the viewpoint of dispersibility of the pigment and encapsulation with the binder resin. % Cumulative particle size value (d50) is 0.5 μm or less. The dispersed particle diameter of the colorant can be measured with a Doppler scattering type particle size distribution measuring apparatus (“MICROTRACK UPA9340” manufactured by Nikkiso Co., Ltd.).

  Examples of known stirrers, emulsifiers and dispersers used at the time of dispersing the colorant include, for example, an ultrasonic homogenizer, a jet mill, a pressure homogenizer, a colloid mill, a ball mill, a sand mill, a paint shaker, and the like, either alone or in combination. May be used.

  The aqueous color press cake of the colorant means a product obtained by dehydrating an aqueous dispersion of the colorant by appropriate filtration. The solid content (colorant) amount in the presscake of the colorant is preferably 30 to 70% by mass, and from the viewpoint of dispersibility of the colorant in the resin, the aqueous presscake becomes 40 to 60% by mass. % Is more preferable.

(Release agent)
The release agent preferably has a melting point of 150 ° C. or lower, more preferably 40 ° C. or higher and 130 ° C. or lower, and particularly preferably 40 ° C. or higher and 110 ° C. or lower.

  Examples of the release agent include low molecular weight polyolefins such as polyethylene; silicones having a melting point (softening point) upon heating; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide, and stearic acid amide; stearin Ester waxes such as stearyl acid; plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax, jojoba oil; animal waxes such as beeswax; montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, Examples thereof include minerals such as Fischer-Tropsch wax and ester wax, petroleum waxes, and modified products thereof.

  The release agent is preferably used in an amount of 1 to 20 parts by mass with respect to 100 parts by mass of the binder resin.

  The mixing form of the releasing agent is not particularly limited, and may be mixed as a dry powder, or may be mixed in the form of an aqueous dispersion or an aqueous dispersion previously dispersed in an aqueous medium. An aqueous dispersion of such a release agent is, for example, a homogenizer or pressure having a strong shearing ability while adding a release agent to an aqueous medium containing a surfactant and heating it above the melting point of the release agent. It can be produced by dispersing in a particle form with a discharge type disperser (for example, “Gorin homogenizer” manufactured by SMT Corporation).

(Charge control agent)
Examples of the charge control agent include quaternary ammonium salt compounds, nigrosine compounds, compounds composed of complexes of aluminum, iron, chromium, zinc, zirconium, and the like. The charge control agent is preferably made of a material that is difficult to dissolve in water from the viewpoint of controlling ionic strength that affects the stability during aggregation and fusion and recycling wastewater.

  The charge control agent is preferably used in an amount of 0.1 to 5 parts by mass with respect to 100 parts by mass of the binder resin from the viewpoint of further improving the chargeability.

(B) Emulsification step and (C) Cooling step Next, the mixture obtained in the mixing step is sealed while being heated to a temperature higher by 10 ° C. than the softening temperature (Tm1) of the first resin having the acid group. Under pressure, a shearing force is applied to obtain a dispersed mixture. Further, while applying a shearing force to the obtained dispersion mixture to a temperature not higher than the glass transition temperature (Tg1) of the first resin having the acid group, at a cooling rate of 0.5 ° C./min to 10 ° C./min. Cooling to obtain an aqueous dispersion of composite fine particles. The 50% particle size of the obtained composite fine particles based on volume distribution is preferably 0.02 μm or more and 1.00 μm or less, more preferably 0.02 μm or more and 0.40 μm or less.

  When the 50% particle size based on the volume distribution exceeds 1.00 μm, the composite fine particles lack storage stability and are liable to cause sedimentation separation. In that case, since the toner particle size is generally about 3 to 8 μm, it is difficult to maintain the composition uniformity of toner particles produced through the aggregation process and the fusion process described later. Therefore, considering the production of toner particles, the 50% particle size of the composite fine particles based on the volume distribution is preferably 0.40 μm or less.

  In order to adjust the 50% particle size of the composite fine particles based on the volume distribution within the above range, the amount of the surfactant, the amount of the basic substance, the melting temperature, and the shearing force may be appropriately adjusted.

  For example, in the emulsification step, it is preferable to apply a shearing force while heating to a temperature 10 to 100 ° C. (more preferably 15 ° C. to 50 ° C.) higher than the softening temperature (Tm1) of the first resin having an acid group. .

  When the difference between the heating temperature and the softening temperature (Tm1) of the first resin having an acid group is less than 10 ° C., a dispersion mixture cannot be obtained. Therefore, the heating temperature needs to be 10 ° C. or more higher than the softening temperature (Tm1) of the first resin having an acid group. In order to obtain a stable dispersion mixture, the heating temperature is preferably 15 ° C. or more higher than the softening temperature (Tm1) of the first resin having an acid group.

  On the other hand, in order to prevent thermal decomposition of the resin, the heating temperature in the emulsification step is preferably + 100 ° C. or less, more preferably + 50 ° C. with respect to the softening temperature (Tm1) of the first resin having an acid group. It is as follows.

  If the warming time is too short, the size of each emulsion varies and it is difficult to obtain a sharp particle size distribution. Therefore, it is preferably 10 minutes or more, and more preferably 20 minutes or more.

  The cooling rate when the obtained emulsion is cooled to a temperature not higher than the glass transition temperature (Tg1) of the first resin having an acid group while applying a shearing force is 0.5 ° C./min to 10 ° C./min. Minutes or less are preferred. Further, the cooling rate is more preferably 0.5 ° C./min to 5 ° C./min. When cooling at a cooling rate exceeding 10 ° C./min, coarse particles are generated, and the particle size distribution of the composite fine particles becomes broad. If the particle size distribution of the composite fine particles is broad, for example, when a toner is produced by an agglomeration method, the colorant in the toner particles becomes non-uniform, which tends to cause problems such as a decrease in density when printed. In addition, the cooling rate in particular from the temperature below the said glass transition temperature (Tg1) to room temperature is not restrict | limited.

  The apparatus used in the method for producing an aqueous dispersion of composite fine particles of the present invention is not particularly limited as long as it can apply a high-speed shearing force in a container that can withstand high temperature and pressure. Examples of the apparatus for applying the high-speed shearing force include CLEARMIX, homomixer, and homogenizer.

(D) Thermal spheronization step Next, the emulsion obtained in the emulsification step and the cooling step is heated to a temperature equal to or higher than the glass transition temperature (Tg1) of the first resin having an acid group, and stirred. An aqueous dispersion of spheroidized composite fine particles is obtained.

  In the thermal spheronization step, stirring is preferably performed while heating to a temperature 0 ° C. to 50 ° C. higher than the glass transition temperature (Tg1) of the first resin having an acid group. More preferably, it is heated to a temperature 5 to 20 ° C higher.

  The average ratio of the major axis / minor axis ratio of the obtained spheroidized composite fine particles is preferably 1.0 or more and 2.0 or less, more preferably 1.0 or more and 1.5 or less. When the circularity exceeds 2.0, the viscosity of the solution in the aggregation process tends to increase, and the particle size distribution of the aggregated particles tends to be broad.

(E) Aggregation step Next, a toner component, an additive, and the like are appropriately mixed in the dispersion liquid of the spheroidized composite fine particles obtained in the thermal spheronization step to prepare a mixed solution. Next, the mixed solution is heated below the glass transition point (Tg1) of the first resin having an acid group to form aggregated particles, thereby adjusting the aggregated particle dispersion. The additives and the like mentioned here are, for example, a pH adjuster, a flocculant, and a stabilizer. They are added to and mixed in the above mixed liquid, and then aggregated in the mixed liquid by appropriately adding temperature, mechanical power, etc. Particles can be formed.

  Furthermore, in the agglomeration step of the present invention, a toner component, an additive, or the like is appropriately mixed with the dispersion of the spheroidized composite fine particles to prepare a mixed solution, and the mixed solution is then mixed with the first resin having an acid group. Subsequent to the primary agglomeration step of heating to a glass transition point (Tg1) or less to form aggregated particles, the aqueous dispersion of the second resin fine particles and the aggregating agent are mixed to carry out the secondary agglomeration step. You can also.

  The addition and mixing of the flocculant is preferably performed at a temperature not higher than the glass transition point (Tg1) of the first resin having an acid group contained in the mixed solution. When the above mixing is performed under this temperature condition, aggregation proceeds in a stable state. The said mixing can be performed using a well-known mixing apparatus, a homogenizer, a mixer, etc.

  The average particle size of the aggregated particles formed here is not particularly limited, but it is usually preferable to control the average particle size to be approximately the same as the average particle size of the toner to be obtained. The control can be easily performed, for example, by appropriately setting and changing the temperature and the stirring and mixing conditions. In the above aggregation step, aggregated particles having an average particle size substantially the same as the average particle size of the toner are formed, and an aggregated particle dispersion liquid in which the aggregated particles are dispersed is prepared.

(Second resin)
Examples of the second resin used in the present invention include homopolymers or copolymers (styrene-based resins) of styrenes such as styrene, parachlorostyrene, and α-methylstyrene; methyl acrylate, acrylic acid Vinyl such as ethyl, n-propyl acrylate, n-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate Homopolymer or copolymer of ester having a group (vinyl resin); Homopolymer or copolymer of vinyl nitrile such as acrylonitrile or methacrylonitrile (vinyl resin); Vinyl ethyl ether, vinyl isobutyl ether Vinyl ether homopolymer or copolymer (vinyl Homopolymers or copolymers of vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketones (vinyl resins); Homopolymers or copolymers of olefins such as ethylene, propylene, butadiene, and isoprene (Olefin resins): Non-vinyl condensation resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, and graft polymers of these non-vinyl condensation resins and vinyl monomers Can be mentioned. These resins may be used alone or in combination of two or more. Of these, a polyester resin having sharp melt properties and excellent strength even at a low molecular weight is particularly preferable.

  The glass transition point (Tg2) of the second resin is preferably 60 ° C. or higher and 80 ° C. or lower, and more preferably 65 ° C. or higher and 80 ° C. or lower. When Tg2 is less than 60 ° C., heat-resistant storage stability is deteriorated, and when it is higher than 100 ° C., fixability is deteriorated.

  The relationship between the glass transition point (Tg1) of the first resin having an acid group and the glass transition point (Tg2) of the second resin is Tg1 <Tg2. Further, if Tg1 and Tg2 are too close, the shell is mixed with the core at the time of fusion, and the core easily moves to the particle surface. Therefore, Tg1 + 5 (° C.) <Tg2 is more preferable. When Tg1 ≧ Tg2, the second resin does not function as a shell.

  The ratio of the second resin to the first resin having an acid group is preferably 3% by mass to 30% by mass, more preferably 5% by mass to 25% by mass, and more preferably 10% to 20%. Most preferably: When the ratio of the second resin to the first resin having an acid group is less than 3% by weight, the heat-resistant storage stability is deteriorated because the core is easily exposed on the toner surface. Getting worse.

(Aqueous dispersion of second resin fine particles)
The aqueous dispersion of the second resin fine particles used in the present invention is prepared by a known method. For example, in the case of a resin particle dispersion containing resin particles containing a vinyl monomer, particularly a styrene monomer, the monomer is subjected to emulsion polymerization using an emulsifier or the like. A particle dispersion can be prepared. In addition, in the case of resins prepared by other methods (for example, polyester resins), if the resin is soluble in a solvent that is oily and has a relatively low solubility in water, the resin is dissolved in those solvents and an emulsifier or A resin particle dispersion can be prepared by dispersing particles in water with a molecular electrolyte together with a disperser such as a homogenizer and then removing the solvent by heating or decompressing. Further, an aqueous medium or an emulsifier may be added to the resin, and the resin may be emulsified and dispersed in water by a disperser that applies high-speed shearing force such as CLEARMIX, homomixer, or homogenizer.

  The volume-based median diameter of the second resin fine particles is preferably 0.05 to 0.3 μm, and more preferably 0.08 to 0.2 μm. If the thickness is 0.3 μm or more, the shell hardly adheres and the shell layer is too thick, so that the fixing property is deteriorated.

(PH adjuster)
Examples of the pH adjusting agent include alkalis such as ammonia and sodium hydroxide, and acids such as nitric acid and citric acid.

(Flocculant)
Examples of the flocculant include monovalent metal salts such as sodium and potassium; divalent metal salts such as calcium and magnesium; trivalent metal salts such as iron and aluminum; and alcohols such as methanol, ethanol and propanol. can give.

(Stabilizer)
Examples of the stabilizer mainly include a surfactant itself or an aqueous medium containing the surfactant.

(F) Fusion process The fusion process is a process in which the aggregated particles are heated and fused. Before entering the fusing step, the pH adjuster, the surfactant, the aggregation terminator and the like can be appropriately added to prevent fusion between the toner particles.

  The heating temperature may be between the temperature of the glass transition point (Tg) of the resin contained in the aggregated particles and the decomposition temperature of the resin.

  As the fusion time, a short time is sufficient if the heating temperature is high, and a long time is necessary if the heating temperature is low. That is, the fusion time depends on the temperature of the heating and cannot be defined in general, but is generally 30 minutes to 10 hours.

(Flocculation terminator)
Examples of the aggregation terminator include trisodium citrate, tripotassium citrate, triammonium citrate, trilithium citrate, tetrasodium ethylenediaminetetraacetate, N- (2-hydroxyethyl) ethylenediamine-N, N ′, N ′. -Chelate resins such as trisodium triacetate, trinitrotriacetic acid trisodium, diethylenetriaminepentaacetic acid pentasodium, triethylenetetraaminehexaacetic acid hexasodium, and sodium polyacrylate and polymethacrylic acid sodium.

  In the present invention, toner particles are obtained by washing, filtering, drying, and the like of the toner obtained after completion of the fusing step under appropriate conditions. Further, a shearing force is applied to the surface of the obtained toner particles by applying inorganic particles such as silica, alumina, titania, calcium carbonate, and resin particles such as vinyl resin, polyester resin, and silicone resin in a dry state. It may be added. These inorganic particles and resin particles function as external additives such as fluidity aids and cleaning aids.

  The physical property measuring method in the present invention will be described below.

<Measurement of Molecular Weight Distribution (Mw / Mn), Weight Average Molecular Weight (Mw), Number Average Molecular Weight (Mn) Measured by Gel Permeation Chromatography (GPC) of Resin Tetrahydrofuran (THF)>
The molecular weight distribution (Mw / Mn), weight average molecular weight (Mw), and number average molecular weight (Mn) measured by GPC of the THF soluble content of the resin are determined as follows.

The column is stabilized in a heat chamber at 40 ° C., and tetrahydrofuran (THF) as a solvent is allowed to flow through the column at this temperature at a flow rate of 1 ml / min, and about 100 μl of THF sample solution is injected and measured. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, for example, one having a molecular weight of about 10 ^{2 to} 10 ⁷ manufactured by Tosoh Corporation or Showa Denko is used, and at least about 10 standard polystyrene samples are suitably used. is there. An RI (refractive index) detector is used as the detector. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns. For example, Shodex GPC KF-801, 802, 803, 804, 805, 806, 807, 800P manufactured by Showa Denko KK, TSKgel G1000H (HXL), G2000H (HXL), G3000H (HXL), G4000H (Tosoh Corporation) HXL), G5000H (HXL), G6000H (HXL), G7000H (HXL), and a combination of TSK guard column.

  The sample is prepared as follows.

  Place the resin (sample) in tetrahydrofuran (THF), leave it for several hours, shake well, mix well with THF (until the sample is united), and let stand for more than 12 hours. At this time, the standing time in THF is set to be 24 hours or more. Thereafter, it is passed through a sample processing filter (pore size 0.45 to 0.5 μm, for example, Mysori Disc H-25-5: manufactured by Tosoh Corporation, Excro Disc 25CR: manufactured by Gelman Science Japan Co., Ltd.). This is used as a GPC sample. The sample concentration is adjusted so that the resin component is 0.5 to 5 mg / ml.

<Measurement of particle size distribution of composite fine particles, spheroidized fine composite particles>
The particle size distribution of fine particles such as composite fine particles and spheroidized composite fine particles is measured using a laser diffraction / scattering type particle size distribution measuring device (LA-920: manufactured by Horiba, Ltd.) according to the operation manual of the device.

  Specifically, the measurement sample was adjusted and the volume distribution was measured at the sample introduction part of the measurement apparatus so that the transmittance was within the measurement range (70 to 95%).

  The 50% particle size based on volume distribution is the particle size (median diameter) corresponding to 50% cumulative, and the 95% particle size based on volume distribution is the particle size corresponding to 95% cumulative from the smallest.

<Measurement of long diameter / short diameter ratio of composite fine particles, spheroidized composite particles>
The major and minor diameters of the composite fine particles and spheroidized composite fine particles are obtained by diluting an aqueous dispersion of fine particles with ion-exchanged water and air-drying them (for example, scanning electron microscope (S-4800: manufactured by Hitachi High-Technologies Corporation). , Hereinafter referred to as SEM), and a value measured using a measurable magnification (taken at 10,000 to 50,000 times)), and the major axis is in contact with the outer shell of the particle and its area The length of the long side and the short diameter of the rectangle drawn so as to be the smallest are the length of the short side of the rectangle. Moreover, the average of a major axis and a minor axis is an average of 50 or more randomly selected particles.

<Measurement of Number Average Particle Size (D1) and Weight Average Particle Size (D4) of Toner Particles>
The number average particle diameter (D1) and weight average particle diameter (D4) of the toner particles are measured by particle size distribution analysis by the Coulter method. A Coulter Counter TA-II or Coulter Multisizer II (manufactured by Coulter Inc.) is used as a measuring device, and measurement is performed according to the operation manual of the device. About 1% sodium chloride aqueous solution is prepared using 1st grade sodium chloride as electrolyte solution. For example, ISOTON-II (manufactured by Coulter Scientific Japan) can be used. As a specific measuring method, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant in 100 to 150 ml of the electrolytic aqueous solution, and 2 to 2 measurement samples (toner particles) are further added. Add 20 mg. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes. The obtained dispersion treatment liquid is subjected to measurement of the volume and number of toners of 2.00 μm or more by the above-described measuring apparatus equipped with 100 μm apertures as apertures, and the toner volume distribution and number distribution are calculated. Then, the number average particle diameter (D1) obtained from the number distribution of the toner particles and the weight average particle diameter (D4) of the toner particles based on the weight obtained from the volume distribution of the toner particles (the median value of each channel is determined for each channel). As a representative value).

  The channels include: 2.00 to 2.52 μm; 2.52 to 3.17 μm; 3.17 to 4.00 μm; 4.00 to 5.04 μm; 5.04 to 6.35 μm; 6.35 to 8 8.00 to 10.08 μm; 10.08 to 12.70 μm; 12.70 to 16.00 μm; 16.00 to 20.20 μm; 20.20 to 25.40 μm; 25.40 to 32.00 μm Use 13 channels of 32.00 to 40.30 μm.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, the aspect of this invention is not limited to these.

<Preparation of colorant aqueous dispersion>
(Preparation of colorant aqueous dispersion 1)
Cyan pigment (CI Pigment Blue 15: 3) 100 parts by weight anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 10 parts by weight ion-exchanged water 890 parts by weight The above was mixed and homogenizer (manufactured by IKA) : Colorant aqueous dispersion 1 in which a cyan pigment was dispersed was prepared by carrying out dispersion for 30 minutes at a rotational speed of 24,000 r / min using Ultra Turrax T50). The 50% particle size of the colorant (cyan pigment) in the colorant dispersion, based on the volume distribution, was 0.34 μm, and the colorant particle concentration was 10% by mass.

(Preparation of colorant aqueous dispersion 2)
Cyan pigment (CI Pigment Blue 15: 3) 100 parts by weight anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 10 parts by weight ion-exchanged water 890 parts by weight The above was mixed and homogenizer (manufactured by IKA) : Ultra-Turrax T50) was used for dispersion for 30 minutes at a rotational speed of 24,000 r / min, and further dispersed under a pressure condition of 200 MPa using a high-pressure impact disperser Nanomizer (manufactured by Yoshida Kikai Kogyo Co., Ltd.) And a colorant aqueous dispersion 2 in which a cyan pigment was dispersed was prepared. In the colorant dispersion, the 50% particle size of the colorant (cyan pigment) based on the volume distribution was 0.12 μm, and the colorant particle concentration was 10% by mass.

(Preparation of colorant aqueous dispersion 3)
A colorant aqueous dispersion 3 was obtained in the same manner as in Production Example 1 of the colorant dispersion except that the cyan pigment was changed to a magenta pigment (CI Pigment Red 122). The 50% particle size based on the volume distribution of the colorant (magenta pigment) in the colorant dispersion was 0.36 μm, and the colorant particle concentration was 10% by mass.

(Preparation of Colorant Water Dispersion 4)
A colorant water dispersion 4 was obtained in the same manner as in Colorant Dispersion Production Example 1 except that the cyan pigment was changed to a yellow pigment (CI Pigment Yellow 74). The 50% particle size of the colorant (yellow pigment) in the colorant dispersion based on the volume distribution was 0.42 μm, and the colorant particle concentration was 10% by mass.

<Preparation of aqueous release agent dispersion>
(Preparation of release agent aqueous dispersion 1)
Paraffin wax (Nippon Seiwa Co., Ltd .: HNP9, melting point 77 ° C.) 100 parts by weight anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 10 parts by weight ion-exchanged water 890 parts by weight After heating to 0 ° C. and dispersing with a homogenizer (IKA: Ultra Turrax T50), the mixture is dispersed with a gorin homogenizer (SMT), and the 50% particle size based on volume distribution is 0.22 μm. A release agent dispersion 1 (release agent concentration: 10% by mass) obtained by dispersing the mold agent was prepared.

(Preparation of release agent aqueous dispersion 2)
Similar to the preparation of the release agent dispersion 1, except that an ester wax (behenyl behenate, melting point 74 ° C.) was used instead of the paraffin wax, the 50% particle size based on the volume distribution was 0.21 μm. A release agent dispersion 2 (release agent concentration: 10% by mass) obtained by dispersing the mold was prepared.

<Preparation of aqueous dispersion of resin fine particles>
(Preparation of resin fine particle aqueous dispersion 1)
Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 g and N, N-dimethylaminoethanol (basic substance) 3.15 g were dissolved in ion-exchanged water (aqueous medium) 146.70 g. A dispersion medium liquid was prepared. This dispersion medium liquid is put into a 350 ml pressure-resistant round bottom stainless steel container, and then “polyester resin A” ((composition (molar ratio) / polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl)). Propane: polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane: terephthalic acid: fumaric acid: trimellitic acid = 25: 25: 26: 20: 4), Mn; 3,500 , Mw; 10,300, Mw / Mn; 2.9, Tm; 96 ° C., Tg; 56 ° C.) 150 g of pulverized material (diameter: 1 to 2 mm) was added and mixed.

  Next, a high-speed shearing emulsifier CLEARMIX (M Technique Co., Ltd .: CLM-2.2S) was hermetically connected to the pressure-resistant round bottom stainless steel container. While heating and pressurizing the mixture in the container to 115 ° C. and 0.18 MPa, the rotor rotation speed of CLEARMIX was set to 18,000 r / min and shear dispersed for 30 minutes. Thereafter, cooling was performed at a cooling rate of 2.0 ° C./min while maintaining a rotation of 18,000 r / min until 50 ° C., thereby obtaining an aqueous dispersion 1 of resin fine particles.

  As a result of observation with an electron microscope (10,000 times), the average minor axis of the resin fine particles was 0.22 μm, the average major axis was 0.56 μm, the average major axis / minor axis was 2.72, and the major axis / short axis. Particles with a diameter smaller than 1.50 accounted for 2% of the total. Further, the 50% particle size based on the volume distribution of the resin fine particles measured using a laser diffraction / scattering particle size distribution measuring apparatus (LA-920: manufactured by Horiba Ltd.) is 0.22 μm, and the 95% particle size is 0. .27 μm.

(Preparation of resin fine particle aqueous dispersion 2)
Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 g and N, N-dimethylaminoethanol (basic substance) 3.15 g were dissolved in ion-exchanged water (aqueous medium) 146.70 g. A dispersion medium liquid was prepared. This dispersion medium liquid is put into a 350 ml pressure-resistant round bottom stainless steel container, followed by “polyester resin B” ((composition (molar ratio) / polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl)). Propane: ethylene glycol: terephthalic acid: maleic acid: trimellitic acid = 35: 15: 33: 15: 2), Mn; 4,600, Mw; 16,500, Mp; 10,400, Mw / Mn; 6, Tm; 117 ° C., Tg; 67 ° C.) 150 g was added and mixed.

  Next, a high-speed shearing emulsifier CLEARMIX (M Technique Co., Ltd .: CLM-2.2S) was hermetically connected to the pressure-resistant round bottom stainless steel container. While heating and pressurizing the mixture in the container to 145 ° C. and 0.41 MPa, the rotor rotation speed of CLEARMIX was sheared and dispersed at 18,000 r / min for 30 minutes. Thereafter, cooling was performed at a cooling rate of 2.0 ° C./min while maintaining the rotation at 18,000 r / min until 50 ° C., thereby obtaining an aqueous dispersion 2 of resin fine particles.

  As a result of observation under an electron microscope (10,000 times), the average minor axis of the resin fine particles was 0.21 μm, the average major axis was 0.53 μm, the average major axis / minor axis was 2.52, and the major axis / short axis. Particles with a diameter smaller than 1.50 accounted for 2% of the total. Further, the 50% particle size based on the volume distribution of the resin fine particles measured using a laser diffraction / scattering particle size distribution analyzer (LA-920: manufactured by Horiba Seisakusho) is 0.26 μm, and the 95% particle size is 0. .29 μm.

(Preparation of resin fine particle aqueous dispersion 3)
Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 g and N, N-dimethylaminoethanol (basic substance) 3.15 g were dissolved in ion-exchanged water (aqueous medium) 146.70 g. A dispersion medium liquid was prepared. This dispersion medium liquid is put into a 350 ml pressure-resistant round bottom stainless steel container, followed by “polyester resin C” ((composition (molar ratio) / polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl)). Propane: polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane: terephthalic acid: fumaric acid: trimellitic acid = 25: 25: 26: 20: 4), Mn; 2,800 , Mw: 9,500, Mw / Mn; 3.4, Tm; 80 ° C., Tg; 55 ° C.) 150 g of pulverized material (diameter: 1 to 2 mm) was added and mixed.

  Next, a high-speed shearing emulsifier CLEARMIX (M Technique Co., Ltd .: CLM-2.2S) was hermetically connected to the pressure-resistant round bottom stainless steel container. While heating and pressurizing the mixture in the container to 115 ° C. and 0.18 MPa, the rotor rotation speed of CLEARMIX was set to 18,000 r / min and shear dispersed for 30 minutes. Thereafter, cooling was performed at a cooling rate of 2.0 ° C./min while maintaining a rotation of 18,000 r / min until 50 ° C., thereby obtaining an aqueous dispersion 3 of resin fine particles.

  As a result of observation under an electron microscope (10,000 times), the average minor axis of the resin fine particles was 0.20 μm, the average major axis was 0.50 μm, the average major axis / minor axis was 2.50, and the major axis / minor axis The number of particles having a value of less than 1.50 was 3% of the total. Further, the 50% particle size based on the volume distribution of the resin fine particles measured using a laser diffraction / scattering type particle size distribution measuring apparatus (LA-920: manufactured by HORIBA, Ltd.) is 0.19 μm, and the 95% particle size is 0. .25 μm.

(Preparation of resin fine particle aqueous dispersion 4)
1.60 g of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) and 1.80 g of N, N-dimethylaminoethanol (basic substance) were dissolved in 174.60 g of ion-exchanged water (aqueous medium). A dispersion medium liquid was prepared. This dispersion medium liquid is put into a 350 ml pressure-resistant round bottom stainless steel container, and then “styrene-acrylic acid-n-butyl-acrylic acid copolymer resin (hereinafter referred to as styrene acrylic resin)” ((, composition (molar ratio ) / Styrene: acrylic acid-n-butyl: acrylic acid (1) = 71: 28: 1), Mn; 2,800, Mw; 12,200, Mp; 9,900, Mw / Mn; 4.4, 120 g of a pulverized product (diameter: 1 to 2 mm) having a Tm of 100 ° C. and Tg of 57 ° C. was added and mixed.

  Next, a high-speed shearing emulsifier CLEARMIX (M Technique Co., Ltd .: CLM-2.2S) was hermetically connected to the pressure-resistant round bottom stainless steel container. While heating and pressurizing the mixture in the container to 115 ° C. and 0.18 MPa, the rotor rotation speed of CLEARMIX was set to 18,000 r / min and shear dispersed for 30 minutes. Thereafter, cooling was performed at a cooling rate of 2.0 ° C./min while maintaining a rotation of 18,000 r / min until 55 ° C., and a resin fine particle aqueous dispersion 4 was obtained.

  The above conditions and the results obtained are shown in Table 1. As a result of observation under an electron microscope (10,000 times), the average minor axis of the resin fine particles was 0.28 μm, the average major axis was 0.73 μm, the average major axis / minor axis was 2.61, and the major axis / short axis Particles with a diameter smaller than 1.50 accounted for 2% of the total. Further, the 50% particle size based on the volume distribution of the resin fine particles measured using a laser diffraction / scattering particle size distribution measuring apparatus (LA-920: manufactured by Horiba Ltd.) is 0.29 μm, and the 95% particle size is 0. .42 μm.

(Preparation of resin fine particle aqueous dispersion 5)
Polyester resin B 60 parts by mass Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.3 parts by mass N, N-dimethylaminoethanol 1.5 parts by mass Tetrahydrofuran (manufactured by Wako Pure Chemical Industries) 200 parts by mass Mix, dissolve, ultra-high speed stirrer K. The mixture was stirred at 4,000 r / min using Robomix (Primix). Further, 180 g of ion-exchanged water was dropped, and then the tetrahydrofuran was removed using an evaporator to obtain a resin fine particle aqueous dispersion 5. The 50% particle size on the basis of volume distribution of the resin fine particles measured using a laser diffraction / scattering particle size distribution analyzer (LA-920: manufactured by HORIBA, Ltd.) is 0.18 μm, and the 95% particle size is 0.25 μm. Met.

<Preparation of aqueous composite fine particle dispersion>
(Composite fine particle dispersion production example 1)
Polyester resin A 120.0 parts by mass Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.12 parts by mass N, N-dimethylaminoethanol (basic substance) 2.52 parts by mass Colorant aqueous dispersion 1 60.0 parts by mass Release agent water dispersion 1 120.0 parts by mass The above was placed in a 350 ml pressure-resistant round bottom stainless steel container and mixed. Next, a high-speed shearing emulsifier CLEARMIX (M Technique Co., Ltd .: CLM-2.2S) was hermetically connected to the pressure-resistant round bottom stainless steel container. While heating and pressurizing the mixture in the container to 115 ° C. and 0.18 MPa, the rotor rotation speed of CLEARMIX was set to 18,000 r / min and shear dispersed for 30 minutes. Thereafter, cooling was performed at a cooling rate of 2.0 ° C./min while maintaining a rotation of 18,000 r / min until 50 ° C., and a composite fine particle aqueous dispersion 1 was obtained.

  As a result of observation with an electron microscope (10,000 times), the average minor axis of the resin fine particles was 0.18 μm, the average major axis was 0.49 μm, and the average major axis / minor axis was 2.75. Further, the 50% particle size based on the volume distribution of the resin fine particles measured using a laser diffraction / scattering particle size distribution measuring apparatus (LA-920: manufactured by Horiba, Ltd.) was 0.21 μm.

(Composite fine particle dispersion production example 2)
The composite fine particle aqueous dispersion 2 was produced by the same method as in the composite fine particle dispersion production example 1 except that the colorant aqueous dispersion 1 was replaced with the colorant aqueous dispersion 2. The average of the major axis / minor axis of the composite fine particle aqueous dispersion 2 was 2.72, and the 50% particle size based on volume distribution was 0.22 μm. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion production example 3)
A composite fine particle aqueous dispersion 3 was produced in the same manner as in the composite fine particle dispersion production example 1 except that the release agent aqueous dispersion 1 was replaced with the release agent aqueous dispersion 2. The average of the major axis / minor axis of the composite fine particle aqueous dispersion 3 was 2.95, and the 50% particle size based on volume distribution was 0.27 μm. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion production example 4)
Polyester resin A 150.0 parts by weight Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 parts by weight N, N-dimethylaminoethanol (basic substance) 3.15 parts by weight Colorant aqueous dispersion 2 75.0 parts by mass ester wax (behenyl behenate, melting point 74 ° C.) 15.0 parts by mass ion-exchanged water The composite fine particles were prepared by the same method as in Production Example of Composite Fine Particle Dispersion 1 except that 56.7 parts by mass were used. An aqueous dispersion 4 was produced. The average of the major axis / minor axis of the composite fine particle aqueous dispersion 4 was 3.07, and the 50% particle size based on volume distribution was 0.23 μm. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion production example 5)
Polyester resin A 150.0 parts by weight Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 parts by weight N, N-dimethylaminoethanol (basic substance) 3.15 parts by weight Colorant aqueous dispersion 2 75.0 parts by mass of ion-exchanged water The composite fine particle aqueous dispersion 5 was produced in the same manner as in the composite fine particle dispersion production example 1 except that 71.7 parts by mass was used. The average of the major axis / minor axis of the composite fine particle aqueous dispersion 5 was 2.86, and the 50% particle size based on volume distribution was 0.25 μm. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion production example 6)
Polyester resin A 150.0 parts by mass Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 parts by mass N, N-dimethylaminoethanol (basic substance) 3.15 parts by mass ester wax (behenic acid) Behenyl, melting point 74 ° C.) The composite fine particle aqueous dispersion 6 was produced in the same manner as in the composite fine particle dispersion production example 1 except that 15.0 parts by mass of ion exchange water and 131.7 parts by mass were used. The average of the major axis / minor axis of the composite fine particle aqueous dispersion 6 was 2.82, and the 50% particle size based on volume distribution was 0.32 μm. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion production example 7)
Polyester resin A 150.0 parts by mass Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 parts by mass N, N-dimethylaminoethanol (basic substance) 3.15 parts by mass release agent water dispersion A composite fine particle aqueous dispersion 7 was produced in the same manner as in the composite fine particle dispersion production example 1 except that the amount was changed to 150.0 parts by mass. The average of the major axis / minor axis of the composite fine particle aqueous dispersion 7 was 2.85, and the 50% particle size based on volume distribution was 0.35 μm. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion production example 8)
Polyester resin B 150.0 parts by weight Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 parts by weight N, N-dimethylaminoethanol (basic substance) 3.15 parts by weight Colorant aqueous dispersion 2 75.0 parts by mass ester wax (behenyl behenate, melting point 74 ° C.) 15.0 parts by mass ion-exchanged water Example of producing a composite fine particle dispersion, except that the heating temperature was changed to 145 ° C. instead of 56.7 parts by mass 1 was used to produce the composite fine particle aqueous dispersion 8. The average of the major axis / minor axis of the composite fine particle aqueous dispersion 8 was 2.76, and the 50% particle size based on volume distribution was 0.29 μm. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion production example 9)
Polyester resin C 150.0 parts by weight Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 parts by weight N, N-dimethylaminoethanol (basic substance) 3.15 parts by weight Colorant aqueous dispersion 2 75.0 parts by mass ester wax (behenyl behenate, melting point 74 ° C.) 15.0 parts by mass ion-exchanged water The composite fine particles were prepared by the same method as in Production Example of Composite Fine Particle Dispersion 1 except that 56.7 parts by mass were used. An aqueous dispersion 9 was produced. The average of the major axis / minor axis of the composite fine particle aqueous dispersion 9 was 2.91, and the 50% particle size based on volume distribution was 0.18 μm. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion production example 10)
Polyester resin A 150.0 parts by weight Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 parts by weight N, N-dimethylaminoethanol (basic substance) 3.15 parts by weight Colorant aqueous dispersion 3 75.0 parts by mass ester wax (behenyl behenate, melting point 74 ° C.) 15.0 parts by mass ion-exchanged water The composite fine particles were prepared in the same manner as in Production Example of Composite Fine Particle Dispersion 1 except that 56.7 parts by mass were used. The water dispersion 10 was manufactured. The average of the major axis / minor axis of the composite fine particle aqueous dispersion 10 was 2.67, and the 50% particle size based on volume distribution was 0.28 μm. The above conditions and the results obtained are shown in Table 1.

(Composite Fine Particle Dispersion Production Example 11)
Polyester resin A 150.0 parts by weight Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 0.15 parts by weight N, N-dimethylaminoethanol (basic substance) 3.15 parts by weight Colorant aqueous dispersion 4 75.0 parts by mass ester wax (behenyl behenate, melting point 74 ° C.) 15.0 parts by mass ion-exchanged water The composite fine particles were prepared by the same method as in Production Example of Composite Fine Particle Dispersion 1 except that 56.7 parts by mass were used. The water dispersion 11 was manufactured. The average of the major axis / minor axis of the composite fine particle aqueous dispersion 11 was 2.88, and the 50% particle size based on volume distribution was 0.35 μm. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion comparative example 1)
A comparative composite fine particle aqueous dispersion 1 was produced in the same manner as in the composite fine particle dispersion production example 1 except that the heating temperature was changed to 95 ° C. In the comparative composite fine particle aqueous dispersion 1, coarse particles were generated and a dispersion could not be obtained. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion comparative example 2)
A comparative composite fine particle aqueous dispersion 2 was produced in the same manner as in the composite fine particle dispersion production example 1 except that the heating temperature was changed to 105 ° C. The average of the major axis / minor axis of the comparative composite fine particle aqueous dispersion 2 was 1.82, and the 50% particle size based on volume distribution was 1.38 μm. The above conditions and the results obtained are shown in Table 1.

(Composite fine particle dispersion comparative example 3)
A comparative composite fine particle aqueous dispersion 3 was produced in the same manner as in the composite fine particle dispersion production example 1 except that the cooling rate was changed to 20.0 ° C./min. The average of the major axis / minor axis of the comparative composite fine particle aqueous dispersion 3 was 1.56, and the 50% particle size based on volume distribution was 1.76 μm. The above conditions and the results obtained are shown in Table 1.

<Preparation of spherical composite fine particle dispersion>
(Sphericalized fine particle dispersion production example 1)
While stirring the composite fine particle dispersion 1, it was heated to 70 ° C. and treated for 30 minutes to produce a spheroidized composite fine particle dispersion 1. The average major axis / minor axis of the spheroidized composite fine particle dispersion 1 was 1.15, and the 50% particle size based on volume distribution was 0.20 μm.

(Sphericalized fine particle dispersion production example 2)
The composite fine particle dispersion 2 was processed by the same method as in the spherical composite fine particle dispersion production example 1 to produce the spherical composite fine particle dispersion 2. The average major axis / minor axis of the spheroidized composite fine particle dispersion 2 was 1.09, and the 50% particle size based on volume distribution was 0.22 μm.

(Sphericalized fine particle dispersion production example 3)
The composite fine particle dispersion 3 was processed by the same method as in the spherical composite fine particle dispersion production example 1 to produce the spherical composite fine particle dispersion 3. The average major axis / minor axis of the spheroidized composite fine particle dispersion 3 was 1.08, and the 50% particle size based on volume distribution was 0.25 μm.

(Spherical composite fine particle dispersion production example 4)
The composite fine particle dispersion 4 was treated in the same manner as in the spherical composite fine particle dispersion production example 1 to produce the spherical composite fine particle dispersion 4. The average major axis / minor axis of the spheroidized composite fine particle dispersion 4 was 1.12, and the 50% particle size based on volume distribution was 0.21 μm.

(Sphericalized fine particle dispersion production example 5)
The composite fine particle dispersion 5 was processed by the same method as in the spherical composite fine particle dispersion production example 1 to produce the spherical composite fine particle dispersion 5. The average of the major axis / minor axis of the spheroidized composite fine particle dispersion 5 was 1.12, and the 50% particle size based on volume distribution was 0.24 μm.

(Spherical composite fine particle dispersion production example 6)
The composite fine particle dispersion 6 was processed by the same method as in the spherical composite fine particle dispersion production example 1 to produce the spherical composite fine particle dispersion 6. The average major axis / minor axis of the spheroidized composite fine particle dispersion 6 was 1.14, and the 50% particle size based on volume distribution was 0.30 μm.

(Sphericalized fine particle dispersion production example 7)
The composite fine particle dispersion 7 was treated in the same manner as in the spherical composite fine particle dispersion production example 1 to produce the spherical composite fine particle dispersion 7. The average major axis / minor axis of the spheroidized composite fine particle dispersion 7 was 1.15, and the 50% particle size based on volume distribution was 0.31 μm.

(Sphericalized fine particle dispersion production example 8)
The composite fine particle dispersion 8 was processed by the same method as in the spherical composite fine particle dispersion production example 1 to produce the spherical composite fine particle dispersion 8. The average major axis / minor axis of the spheroidized composite fine particle dispersion 8 was 1.17, and the 50% particle size based on volume distribution was 0.27 μm.

(Sphericalized fine particle dispersion production example 9)
The composite fine particle dispersion 9 was processed by the same method as in the spherical composite fine particle dispersion production example 1 to produce the spherical composite fine particle dispersion 9. The average major axis / minor axis of the spheroidized composite fine particle dispersion 9 was 1.10, and the 50% particle size based on volume distribution was 0.17 μm.

(Sphericalized composite fine particle dispersion production example 10)
The composite fine particle dispersion 10 was treated in the same manner as in the spherical composite fine particle dispersion production example 1 to produce the spherical composite fine particle dispersion 10. The average major axis / minor axis of the spheroidized composite fine particle dispersion 10 was 1.16, and the 50% particle size based on volume distribution was 0.25 μm.

(Sphericalized fine composite particle production example 11)
The composite fine particle dispersion 11 was processed by the same method as in the spherical composite fine particle dispersion production example 1 to produce the spherical composite fine particle dispersion 11. The average major axis / minor axis of the spheroidized composite fine particle dispersion 11 was 1.13, and the 50% particle size based on volume distribution was 0.32 μm.

(Sphericalized fine composite particle production example 12)
While stirring the composite fine particle dispersion 1, it was heated to 80 ° C. and treated for 30 minutes to produce a spheroidized composite fine particle dispersion 12. The average major axis / minor axis of the spheroidized composite fine particle dispersion 12 was 1.07, and the 50% particle size based on volume distribution was 0.20 μm.

(Sphericalized fine composite particle production example 13)
While stirring the composite fine particle dispersion 1, it was heated to 60 ° C. and treated for 30 minutes to produce a spheroidized composite fine particle dispersion 13. The average major axis / minor axis of the spheroidized composite fine particle dispersion 13 was 1.17, and the 50% particle size based on volume distribution was 0.21 μm.

(Sphericalized fine particle dispersion production example 14)
While stirring the composite fine particle dispersion 1, it was heated to 70 ° C. and treated for 60 minutes to produce a spheroidized composite fine particle dispersion 14. The average major axis / minor axis of the spheroidized composite fine particle dispersion 14 was 1.06, and the 50% particle size based on volume distribution was 0.20 μm.

(Sphericalized composite fine particle dispersion comparative example 1)
The composite fine particle dispersion 1 was heated to 50 ° C. with stirring and treated for 30 minutes to produce a comparative spheroidized composite fine particle dispersion 1. The average of the major axis / minor axis of the comparative spheroidized composite fine particle dispersion 1 was 2.23, and the 50% particle size based on volume distribution was 0.21 μm.

(Spherical composite fine particle dispersion comparative example 2)
While the comparative composite fine particle dispersion 2 was stirred, it was heated to 50 ° C. and treated for 30 minutes to produce a comparative spheroidized composite fine particle dispersion 2. The average of the major axis / minor axis of the comparative spheroidized composite fine particle dispersion 2 was 2.41, and the 50% particle size on the basis of volume distribution was 1.18 μm.

(Spherical composite fine particle dispersion comparative example 3)
While the comparative composite fine particle dispersion 2 was stirred, it was heated to 70 ° C. and treated for 30 minutes to produce a comparative spheroidized composite fine particle dispersion 3. The average of the major axis / minor axis of the comparative spheroidized composite fine particle dispersion 3 was 1.17, and the 50% particle size on the basis of volume distribution was 1.14 μm.

(Spherical composite fine particle dispersion comparative example 4)
While the comparative composite fine particle dispersion 3 was stirred, it was heated to 70 ° C. and treated for 30 minutes to produce a comparative spheroidized composite fine particle dispersion 4. The average of the major axis / minor axis of the comparative spheroidized composite fine particle dispersion 4 was 1.18, and the 50% particle size based on volume distribution was 1.42 μm.

<Toner particle preparation>
[Example 1]
Spherical composite fine particle dispersion 1 40 parts by mass Ion-exchanged water 122.4 parts by mass The above was sufficiently mixed and dispersed in a stainless steel flask using a homogenizer (manufactured by IKA: Ultra Turrax T50). Subsequently, 20 mass parts of magnesium sulfate aqueous solution (1 mass%) was added to this, and dispersion | distribution operation was continued with the homogenizer. The flask was heated with stirring in an oil bath for heating. After maintaining at 45 ° C. for 60 minutes, observation with an optical microscope confirmed that aggregated particles having an average particle diameter of about 5.41 μm were formed. After adding 40 parts by mass of a trisodium citrate aqueous solution (5% by mass), the temperature was raised to 80 ° C. and maintained for 120 minutes while continuing stirring. Then, after cooling the obtained liquid to 25 degreeC, it filtered and solid-liquid-separated, Then, 800 g of ion-exchange water was added to solid content, and it was stirred and washed for 30 minutes. Thereafter, filtration and solid-liquid separation were performed again. Filtration and washing as described above were repeated until the electrical conductivity of the filtrate was 150 μS / cm or less in order to eliminate the influence of the residual surfactant. Next, toner particles 1 were obtained by drying the obtained solid content. When the toner particles 1 were measured by the above Coulter Multisizer II (manufactured by Coulter Inc.), the weight average particle diameter D4 was 5.22 μm and the number average particle diameter D1 was 4.39 μm. That is, D4 / D1 is 1.19, and the toner particles 1 have a sharp particle size distribution.

[Example 2]
Toner particles 2 were produced in the same manner as in Example 1 except that the spheroidized composite fine particle dispersion 1 described in Example 1 was changed to the spheroidized composite fine particle dispersion 2. Toner particles 2 had a weight average particle diameter D4 of 5.32 μm and a number average particle diameter D1 of 4.51 μm. That is, D4 / D1 was 1.18.

Example 3
Spherical composite fine particle dispersion 4 60 parts by mass Ion-exchanged water 120 parts by mass The above was sufficiently mixed and dispersed in a stainless steel flask using a homogenizer (manufactured by IKA: Ultra Turrax T50). Subsequently, 20 mass parts of magnesium sulfate aqueous solution (1 mass%) was added to this, and dispersion | distribution operation was continued with the homogenizer. The flask was heated with stirring in an oil bath for heating. After maintaining at 45 ° C. for 60 minutes, observation with an optical microscope confirmed that aggregated particles having an average particle diameter of about 5.31 μm were formed. After adding 40 parts by mass of a trisodium citrate aqueous solution (5% by mass), the temperature was raised to 80 ° C. and maintained for 120 minutes while continuing stirring. Then, after cooling the obtained liquid to 25 degreeC, it filtered and solid-liquid-separated, Then, 800 g of ion-exchange water was added to solid content, and it was stirred and washed for 30 minutes. Thereafter, filtration and solid-liquid separation were performed again. Filtration and washing as described above were repeated until the electrical conductivity of the filtrate was 150 μS / cm or less in order to eliminate the influence of the residual surfactant. Next, toner particles 3 were obtained by drying the obtained solid content.

  When the toner particles 3 were measured by the above Coulter Multisizer II (manufactured by Coulter Inc.), the weight average particle diameter D4 was 5.19 μm and the number average particle diameter D1 was 4.36 μm. That is, D4 / D1 was 1.19.

Example 4
Spherical composite fine particle dispersion 4 60 parts by mass Ion-exchanged water 120 parts by mass The above was sufficiently mixed and dispersed in a stainless steel flask using a homogenizer (manufactured by IKA: Ultra Turrax T50). Subsequently, 20 mass parts of magnesium sulfate aqueous solution (1 mass%) was added to this, and dispersion | distribution operation was continued with the homogenizer. The flask was heated with stirring in an oil bath for heating. After maintaining at 45 ° C. for 60 minutes, observation with an optical microscope confirmed that aggregated particles having an average particle diameter of about 5.12 μm were formed.

  Next, 12 parts by mass of the resin fine particle dispersion 2 was added and stirred for 30 minutes. Then, after adding 40 mass parts of trisodium citrate aqueous solution (5 mass%), it heated up to 80 degreeC and continued for 120 minutes, continuing stirring. Then, after cooling the obtained liquid to 25 degreeC, it filtered and solid-liquid-separated, Then, 800 g of ion-exchange water was added to solid content, and it was stirred and washed for 30 minutes. Thereafter, filtration and solid-liquid separation were performed again. Filtration and washing as described above were repeated until the electrical conductivity of the filtrate was 150 μS / cm or less in order to eliminate the influence of the residual surfactant. Next, toner particles 4 were obtained by drying the obtained solid content.

  The toner particles 4 had a weight average particle diameter D4 of 5.49 μm and a number average particle diameter D1 of 4.65 μm. That is, D4 / D1 was 1.18.

Example 5
Toner particles 5 were produced in the same manner as in Example 4 except that the resin fine particle dispersion 2 described in Example 4 was changed to the resin particle dispersion 4. The toner particles 5 had a weight average particle diameter D4 of 5.58 μm and a number average particle diameter D1 of 4.69 μm. That is, D4 / D1 was 1.19.

Example 6
Toner particles 6 were produced in the same manner as in Example 4 except that the resin fine particle dispersion 2 described in Example 4 was changed to the resin particle dispersion 5. The toner particles 5 had a weight average particle diameter D4 of 5.61 μm and a number average particle diameter D1 of 4.75 μm. That is, D4 / D1 was 1.18.

Example 7
Toner particles 7 were produced in the same manner as in Example 4 except that the resin fine particle dispersion 2 described in Example 4 was changed to the spherical composite fine particles 8. Toner particles 7 had a weight average particle diameter D4 of 5.41 μm and a number average particle diameter D1 of 4.55 μm. That is, D4 / D1 was 1.19.

Example 8
Toner particles 8 were produced in the same manner as in Example 4 except that the spheroidized composite particles 4 described in Example 4 were changed to spheroidized composite particles 9. The toner particles 8 had a weight average particle diameter D4 of 5.53 μm and a number average particle diameter D1 of 4.69 μm. That is, D4 / D1 was 1.18.

Example 9
Toner particles 9 were produced in the same manner as in Example 4 except that 12 parts by mass of the resin fine particle dispersion 2 described in Example 4 was changed to 18 parts by mass. The toner particles 9 had a weight average particle diameter D4 of 5.72 μm and a number average particle diameter D1 of 4.85 μm. That is, D4 / D1 was 1.18.

Example 10
The toner particles 10 were produced in the same manner as in Example 4 except that 12 parts by mass of the resin fine particle dispersion 2 described in Example 4 was changed to 6 parts by mass. The toner particles 10 had a weight average particle diameter D4 of 5.51 μm and a number average particle diameter D1 of 4.67 μm. That is, D4 / D1 was 1.18.

Example 11
Spherical composite fine particle dispersion 5 60 parts by mass Spherical composite fine particle dispersion 6 60 parts by mass Ion-exchanged water 60 parts by mass In a stainless steel flask, a homogenizer (manufactured by IKA: Ultra Turrax T50) Mixed and dispersed. Subsequently, 20 mass parts of magnesium sulfate aqueous solution (1 mass%) was added to this, and dispersion | distribution operation was continued with the homogenizer. The flask was heated with stirring in an oil bath for heating. After maintaining at 45 ° C. for 60 minutes, observation with an optical microscope confirmed that aggregated particles having an average particle diameter of about 5.22 μm were formed.

  Next, 12 parts by mass of the resin fine particle dispersion 2 was added and stirred for 30 minutes. Then, after adding 40 mass parts of trisodium citrate aqueous solution (5 mass%), it heated up to 80 degreeC and continued for 120 minutes, continuing stirring. Then, after cooling the obtained liquid to 25 degreeC, after filtering and solid-liquid separation, 800 g of ion-exchange water was added to solid content, and it stirred and washed for 30 minutes. Thereafter, filtration and solid-liquid separation were performed again. Filtration and washing as described above were repeated until the electrical conductivity of the filtrate was 150 μS / cm or less in order to eliminate the influence of the residual surfactant. Next, toner particles 11 were obtained by drying the obtained solid content.

  The toner particles 11 had a weight average particle diameter D4 of 5.31 μm and a number average particle diameter D1 of 4.46 μm. That is, D4 / D1 was 1.19.

Example 12
Toner particles 12 were produced in the same manner as in Example 11 except that the spheroidized composite fine particle dispersion 6 described in Example 11 was changed to the spheroidized composite fine particle dispersion 7. The toner particles 12 had a weight average particle diameter D4 of 5.40 μm and a number average particle diameter D1 of 4.54 μm. That is, D4 / D1 was 1.19.

Example 13
Toner particles 13 were produced in the same manner as in Example 4 except that the spheroidized composite fine particle dispersion 4 described in Example 4 was changed to the spheroidized composite fine particle dispersion 10. Toner particles 13 had a weight average particle diameter D4 of 5.52 μm and a number average particle diameter D1 of 4.64 μm. That is, D4 / D1 was 1.19.

Example 14
Toner particles 14 were produced in the same manner as in Example 4 except that the spheroidized composite fine particle dispersion 4 described in Example 4 was changed to the spheroidized composite fine particle dispersion 11. The toner particles 14 had a weight average particle diameter D4 of 5.36 μm and a number average particle diameter D1 of 4.50 μm. That is, D4 / D1 was 1.19.

Example 15
Toner particles 15 were produced in the same manner as in Example 4 except that the spheroidized composite fine particle dispersion 4 described in Example 4 was changed to the spheroidized composite fine particle dispersion 3. The toner particles 15 had a weight average particle diameter D4 of 5.27 μm and a number average particle diameter D1 of 4.54 μm. That is, D4 / D1 was 1.16.

Example 16
Toner particles 16 were produced in the same manner as in Example 4 except that the spheroidized composite fine particle dispersion 4 described in Example 4 was changed to the spheroidized composite fine particle dispersion 12. The toner particles 16 had a weight average particle diameter D4 of 5.38 μm and a number average particle diameter D1 of 4.56 μm. That is, D4 / D1 was 1.18.

Example 17
Toner particles 17 were produced in the same manner as in Example 4 except that the spheroidized composite fine particle dispersion 4 described in Example 4 was changed to the spheroidized composite fine particle dispersion 13. Toner particles 17 had a weight average particle diameter D4 of 5.62 μm and a number average particle diameter D1 of 4.72 μm. That is, D4 / D1 was 1.19.

Example 18
Toner particles 18 were produced in the same manner as in Example 4 except that the spheroidized composite fine particle dispersion 4 described in Example 4 was changed to the spheroidized composite fine particle dispersion 14. The weight average particle diameter D4 of the toner particles 18 is 5.77 μm, and the number average particle diameter D1 is 4.89 μm. That is, D4 / D1 was 1.18.

[Comparative Example 1]
Resin fine particle dispersion 1 40 parts by weight Colorant dispersion 1 10 parts by weight Release agent dispersion 1 20 parts by weight Ion-exchanged water 110 parts by weight In a stainless steel flask, a homogenizer (manufactured by IKA: Ultra Turrax T50) is used. And mixed and dispersed thoroughly. Subsequently, 20 mass parts of magnesium sulfate aqueous solution (1 mass%) was added to this, and dispersion | distribution operation was continued with the homogenizer. The flask was heated with stirring in an oil bath for heating. After maintaining at 45 ° C. for 60 minutes, observation with an optical microscope confirmed that aggregated particles having an average particle diameter of about 5.31 μm were formed. After adding 40 parts by mass of a trisodium citrate aqueous solution (5% by mass), the temperature was raised to 80 ° C. and maintained for 120 minutes while continuing stirring. Then, after cooling the obtained liquid to 25 degreeC, it filtered and solid-liquid-separated, Then, 800 g of ion-exchange water was added to solid content, and it was stirred and washed for 30 minutes. Thereafter, filtration and solid-liquid separation were performed again. Filtration and washing as described above were repeated until the electrical conductivity of the filtrate was 150 μS / cm or less in order to eliminate the influence of the residual surfactant. Next, comparative toner particles 1 were obtained by drying the obtained solid content.

  Comparative toner particle 1 had a weight average particle diameter D4 of 5.72 μm and a number average particle diameter D1 of 4.81 μm. That is, D4 / D1 was 1.19.

[Comparative Example 2]
Comparative toner particles 2 were produced in the same manner as in Example 3 except that the spherical composite fine particle dispersion 4 described in Example 3 was changed to the composite fine particle dispersion 2. The comparative toner particles 2 had a weight average particle diameter D4 of 7.63 μm and a number average particle diameter D1 of 5.16 μm. That is, D4 / D1 was 1.48.

[Comparative Example 3]
Comparative toner particles 3 were produced in the same manner as in Example 3 except that the spheroidized composite fine particle dispersion 4 described in Example 3 was changed to the composite fine particle dispersion 8. Comparative toner particles 3 had a weight average particle diameter D4 of 7.42 μm and a number average particle diameter D1 of 5.19 μm. That is, D4 / D1 was 1.43.

[Comparative Example 4]
Comparative toner particles 4 were produced in the same manner as in Example 3 except that the spheroidized composite fine particle dispersion 4 described in Example 3 was changed to the spheroidized composite fine particle dispersion 8. The comparative toner particles 4 had a weight average particle diameter D4 of 5.62 μm and a number average particle diameter D1 of 4.72 μm. That is, D4 / D1 was 1.19.

[Comparative Example 5]
Comparative toner particles 5 were produced in the same manner as in Example 3, except that the spheroidized composite fine particle dispersion 4 described in Example 3 was changed to the comparative spheroidized composite fine particle dispersion 1. The comparative toner particles 5 had a weight average particle diameter D4 of 7.21 μm and a number average particle diameter D1 of 5.22 μm. That is, D4 / D1 was 1.38.

[Comparative Example 6]
Comparative toner particles 6 were produced in the same manner as in Example 3 except that the spheroidized composite fine particle dispersion 4 described in Example 3 was changed to the comparative spheroidized composite fine particle dispersion 2. The comparative toner particles 6 had a weight average particle diameter D4 of 7.15 μm and a number average particle diameter D1 of 5.14 μm. That is, D4 / D1 was 1.39.

[Comparative Example 7]
Comparative toner particles 7 were produced in the same manner as in Example 4 except that the resin fine particle dispersion 2 described in Example 4 was changed to the resin fine particle dispersion 1. Comparative toner particles 7 had a weight average particle diameter D4 of 5.49 μm and a number average particle diameter D1 of 4.65 μm. That is, D4 / D1 was 1.18.

[Comparative Example 8]
Comparative toner particles 8 were produced in the same manner as in Example 4 except that the resin fine particle dispersion 2 described in Example 4 was changed to the resin fine particle dispersion 3. The comparative toner particles 8 had a weight average particle diameter D4 of 5.57 μm and a number average particle diameter D1 of 4.72 μm. That is, D4 / D1 was 1.18.

[Comparative Example 9]
Comparative toner particles 9 were produced in the same manner as in Comparative Example 7, except that the spheroidized composite fine particle dispersion 4 described in Comparative Example 7 was changed to the spheroidized composite fine particle dispersion 8. The comparative toner particles 9 had a weight average particle diameter D4 of 5.65 μm and a number average particle diameter D1 of 4.75 μm. That is, D4 / D1 was 1.19.

[Comparative Example 10]
Comparative toner particles 10 were produced in the same manner as in Comparative Example 7 except that the spheroidized composite fine particle dispersion 4 described in Comparative Example 7 was changed to the spheroidized composite fine particle dispersion 1. The comparative toner particles 10 had a weight average particle diameter D4 of 7.52 μm and a number average particle diameter D1 of 5.45 μm. That is, D4 / D1 was 1.38.

[Comparative Example 11]
Comparative toner particles 11 were produced in the same manner as in Example 4 except that 12 parts by mass of resin fine particle dispersion 2 described in Example 4 was changed to 0.6 parts by mass. The comparative toner particles 11 had a weight average particle diameter D4 of 5.66 μm and a number average particle diameter D1 of 4.76 μm. That is, D4 / D1 was 1.19.

[Comparative Example 12]
Comparative toner particles 12 were produced in the same manner as in Example 4 except that 12 parts by mass of resin fine particle dispersion 2 described in Example 4 was changed to 24 parts by mass. The comparative toner particles 12 had a weight average particle diameter D4 of 5.82 μm and a number average particle diameter D1 of 4.93 μm. That is, D4 / D1 was 1.18.

[Comparative Example 13]
Comparative toner particles 13 were produced in the same manner as in Example 3 except that the spheroidized composite fine particle dispersion 4 described in Example 3 was changed to the comparative spheroidized composite fine particle dispersion 3. The comparative toner particles 13 had a weight average particle diameter D4 of 8.75 μm and a number average particle diameter D1 of 6.39 μm. That is, D4 / D1 was 1.37.

[Comparative Example 14]
Comparative toner particles 14 were produced in the same manner as in Example 3, except that the spheroidized composite fine particle dispersion 4 described in Example 3 was changed to the comparative spheroidized composite fine particle dispersion 4. The comparative toner particles 14 had a weight average particle diameter D4 of 9.56 μm and a number average particle diameter D1 of 7.13 μm. That is, D4 / D1 was 1.34.

  Table 2 shows the evaluation results such as the particle size distribution of the toner particles 1 to 18 and the comparative toner particles 1 to 14.

  Further, the following evaluation was performed using toner particles 1 to 18 and comparative toner particles 1 to 14. The results are shown in Table 2.

(Evaluation of development stability)
To 100 parts by mass of each toner particle, 1.8 parts by mass of hydrophobized silica fine powder having a specific surface area measured by the BET method of 200 m ² / g was dry-mixed with a Henschel mixer (manufactured by Mitsui Mining). An external toner was obtained.

  Each externally added toner and a ferrite carrier surface-coated with a silicone resin (average particle size 42 μm) were mixed to a toner concentration of 6% by mass to prepare a two-component developer. A commercially available full-color digital copying machine (CLC1100, manufactured by Canon Inc.) was used, and 80 g of toner was filled in a cyan cartridge. Using plain paper (color laser copier paper, manufactured by Canon), a 2% printing chart was continuously printed until the toner was exhausted.

Development stability was evaluated according to the following evaluation criteria.
○: Good image quality is maintained ×: Image quality deterioration due to fogging and scattering was observed

(Evaluation of fixability)
Each externally added toner and a ferrite carrier surface-coated with a silicone resin (average particle size 42 μm) were mixed to a toner concentration of 6% by mass to prepare a two-component developer. A commercially available full color digital copying machine (CLC1100, manufactured by Canon Inc.) was used to form an unfixed toner image (0.6 mg / cm ² ) on the image receiving paper (64 g / m ² ). A fixing unit removed from a commercially available color laser printer (LBP-5500, manufactured by Canon) was remodeled so that the fixing temperature could be adjusted, and a fixing test of an unfixed image was performed using this. Under normal temperature and humidity, the process speed is set to 100 mm / second, the set temperature is swung at 10 points every 10 ° C. within the range of 120 ° C. to 200 ° C., and the offset state when the unfixed image is fixed is visually observed. And evaluated. The evaluation results are shown in Table 2.

[Fixing temperature range where no offset occurs]
<120 to 200 ° C / all 9 points>
◎: 7 points or more ○: 5 points or more ×: 4 points or less

(Evaluation of blocking resistance)
Each externally added toner was allowed to stand for 24 hours in a thermostatic chamber adjusted to the same temperature as the glass transition point of each first resin, and the degree of blocking was evaluated. The evaluation results are shown in Table 2.
A: Blocking does not occur. O: Blocking occurs, but disperses easily when force is applied.
X: Blocking occurs and does not disperse even when force is applied.

Claims (11)

Mixing step (B) for obtaining a mixture by mixing (A) at least a first resin having an acid group, a basic substance, a surfactant, a colorant and / or a release agent in an aqueous medium. An emulsification step of obtaining an emulsion by applying a shearing force while heating to a temperature 10 ° C. or more higher than the softening temperature (Tm1) of the first resin having an acid group;
(C) While applying a shearing force to the emulsion at a temperature not higher than the glass transition temperature (Tg1) of the first resin having the acid group, at a cooling rate of 0.5 ° C./min to 10 ° C./min. A cooling step of cooling to obtain composite fine particles containing the first resin having the acid group, the release agent and / or the colorant;
(D) a thermal spheronization step in which the composite fine particles are heated to a temperature equal to or higher than the glass transition temperature (Tg1) of the first resin having an acid group to obtain spherical composite fine particles;
(E) an aggregation step of aggregating at least the spheroidized composite fine particles with an aggregating agent in the aqueous medium at a temperature equal to or lower than the glass transition temperature (Tg1) of the first resin having an acid group; ,
(F) A toner having each step of a fusion step in which the aggregated particles are heated to a temperature equal to or higher than the glass transition temperature (Tg1) of the first resin having an acid group and fused to obtain toner particles. Manufacturing method. In the agglomeration step, the spheroidized composite fine particles are agglomerated with an aggregating agent at a temperature equal to or lower than the glass transition temperature (Tg1) of the first resin having an acid group in the aqueous medium to form core agglomerated particles. Process,
Next, the second resin fine particles are mixed, and the second resin fine particles are adhered to the core aggregated particles to obtain core / shell aggregated particles, and at least a second aggregation step is performed, and the first resin having the acid group The toner production method according to claim 1, wherein the relationship between the glass transition point (Tg1) of the second resin and the glass transition point (Tg2) of the second resin is Tg1 <Tg2.   The toner production method according to claim 2, wherein a ratio of the second resin to the first resin having an acid group is 3% by mass or more and 30% by mass or less.   4. The method for producing a toner according to claim 2, wherein the first resin having an acid group has a softening temperature (Tm1) of 70 ° C. or higher and 110 ° C. or lower. 5.   The toner production method according to claim 2, wherein the glass transition point (Tg2) of the second resin is 60 ° C. or more and 80 ° C. or less.   6. The toner manufacturing method according to claim 2, wherein a median diameter based on a volume distribution of the second resin fine particles is 0.05 μm or more and 0.3 μm or less.   7. The toner manufacturing method according to claim 1, wherein a 50% particle size of the composite particle based on a volume distribution is 0.02 μm or more and 1.00 μm or less.   The toner production method according to any one of claims 1 to 7, wherein an average ratio of major axis / minor axis of the spheroidized composite fine particles is 1.0 or more and 2.0 or less.   The method for producing a toner according to claim 1, wherein the resin having an acid group is a polyester resin.   The method for producing a toner according to claim 1, wherein the basic substance is an amine.   A toner obtainable by the method for producing a toner according to claim 1.