JP2018097251A - Method for manufacturing toner for electrostatic charge image development - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner for electrostatic latent image development that has a proper hue while maintaining low-temperature fixability, and is excellent in light resistance.SOLUTION: A method for manufacturing a toner includes the steps of: dispersing resin fine particles in a solvent to produce a resin fine particle dispersion liquid; dispersing colorant particles in a solvent to produce colorant particle dispersion liquid; mixing at least the resin fine particle dispersion liquid and the colorant particle dispersion liquid in water to form toner base particles; washing the toner base particles; and providing an external additive to the toner base particles, where the colorant particle dispersion liquid contains at least a compound A represented by the formula (1).SELECTED DRAWING: None

Description

  The present invention relates to a yellow toner and an emulsion ink used in an image forming method by an electrophotographic method, an electrostatic recording method, and a toner jet method.

In electrophotography, a photoconductive material is generally used, and a latent image is formed on the photosensitive member by various means, and then the latent image is developed with toner, and an intermediate transfer is performed as necessary. Using the mechanism, the toner image is finally transferred to a transfer medium such as paper, and then the image is fixed on the medium by heating, pressurization, heat pressurization, or solvent vapor to obtain a print image.
In recent years, full-color printers and full-color copiers that use polymerized toner have been used against the backdrop of growing market demands for high image quality close to that of gravure printing and government agencies promoting energy conservation in printers and copiers. Demand is increasing. In color image formation by full-color electrophotography, it is common to reproduce all colors by laminating four color toners obtained by adding black to three color toners of yellow, magenta, and cyan.

  The polymerized toner has a fine particle size, sharp particle size distribution and sharp chargeability, excellent fine line reproducibility, and a clear printed image with few image defects such as scattering, dirt and fog caused by improper chargeability. There is a feature that is. Usually, heat-resistant storage stability and fixability are in a trade-off relationship, but polymerized toners have excellent durability and environmental resistance by controlling the capsule structure, which is a characteristic of polymerized toners. By disposing the shell and arranging the core excellent in low-temperature fixability on the inner side, it is possible to exhibit excellent performance that achieves both heat-resistant storage stability and low-temperature fixability.

  Conventionally, paper has been generally used as a printing medium. However, in recent years, printing on a medium such as fabric or ceramics directly or via a thermal transfer sheet is generally performed. The toner is used in various ways. For such applications, a polymerized toner that can control the three-dimensional structure and can freely design the viscoelasticity of the core can exhibit excellent performance.

  Various methods for producing the polymerized toner have been proposed, and those that have been put to practical use include an emulsion polymerization aggregation method, a suspension polymerization method, a polyester elongation method, and a dissolution suspension method. Among them, the emulsion polymerization aggregation method toner that agglomerates emulsion particles mainly composed of a binder resin and pigment fine particles in an aqueous medium system that does not use an organic solvent has a low environmental impact in the production process, and the toner capsule. The design freedom of the structure is high, and the shape, particle size, and particle size distribution can be designed freely.

An emulsion polymerization agglomeration method that aggregates and produces emulsion particles and pigment fine particles that are based on a binder resin in an aqueous medium system that does not use an organic solvent, which is an environmentally friendly and excellent production method in terms of performance and cost. A lot of studies have been made on yellow toners that are excellent in safety, color developability, and wide color gamut of color reproducibility.
Conventionally, in an emulsion polymerization aggregation method or suspension polymerization method produced in an aqueous medium, a yellow toner is used as a C.I. I. Pigment yellow 73 (PY73), C.I. I. Pigment Yellow 74 (PY74) is often used. However, it has been pointed out that these pigments have a relatively high hydrophilicity and tend to be distributed largely in the vicinity of the surface layer during the production of the toner, and as a result, are easily exposed on the surface of the toner particles.

In general, when the pigment is exposed on the toner surface, it tends to deteriorate over time during long-term use, and tends to contaminate the machine and components, resulting in image defects such as fog and dirt. . Furthermore, these pigments have poor dispersibility and tend to be reddish, so they have excellent reproducibility in the yellow and red color gamuts, but are inferior in reproducibility in the green color gamut. It was not able to cope enough. Furthermore, in the sRGB standard, the lightness of green is required to be higher than magenta, and the yellow pigment is not compatible. In addition, these pigments have poor light resistance, and are not suitable as toner pigments for professional printing markets such as gravure printing and POP advertisement, which have severe aging and fading tolerance in exposure.

  Examples of yellow pigments having excellent light resistance include isoindoline pigments C.I. I. Pigment Yellow 185 (PY185), azomethine pigment C.I. I. Pigment Yellow 150 (PY150) and the like, and polyester toners by a kneading pulverization method containing Pigment Yellow 185 and polymerized toners by a solution suspension method containing Pigment Yellow 155 have been reported (see Patent Documents 1 and 2). In addition, it has been reported that Pigment Yellow 155 and Pigment Yellow 185 are used in a polyester toner produced by a solution suspension method in order to solve light resistance and transparency (see Patent Document 3).

JP 2005-106932 A Japanese Patent Laid-Open No. 2004-212451 JP 2011 197032 A

  However, the toner containing Pigment Yellow 185 described in Patent Document 1 has a problem in storage stability, chargeability, and fluidity under high temperature and high humidity because Pigment Yellow 185 has a high transferability to the toner surface. . The toner containing Pigment Yellow 155 described in Patent Document 2 has to increase the adhesion amount of the toner or increase the pigment addition amount in the toner in order to obtain a sufficient image density, and the low-temperature fixability is impaired. There was a problem. Also in the technique described in Patent Document 3, the low-temperature fixing of the toner is impaired due to the influence of the resin coating for surface treatment for suppressing the humidity dependence caused by Pigment Yellow 185. On the other hand, in the solution suspension method, When the resin coat is not applied, there is a possibility that Pigment Yellow 185 is unevenly distributed on the toner surface. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for producing a toner for developing an electrostatic latent image having an appropriate hue and excellent light resistance while maintaining low-temperature fixability. Is to provide.

The present inventor has conducted intensive research to solve the above-mentioned problems. As a result, in order to maintain a low temperature fixability, have an appropriate hue, and be excellent in light resistance, a toner having a specific process can be produced. The knowledge that it was effective to contain a specific pigment in the method was obtained, and further studies were made based on this knowledge, thereby completing the present invention. That is, the aspect of this invention is as follows.
[1] A step of preparing a resin fine particle dispersion by dispersing resin fine particles in a solvent,
A step of dispersing colored particles in a solvent to prepare a colored particle dispersion;
A step of mixing at least the resin fine particle dispersion and the colored particle dispersion in water to form toner base particles;
Cleaning the toner base particles;
Adding an external additive to the toner base particles,
A method for producing a toner, wherein the colored particle dispersion contains at least a compound A represented by the following general formula (1).

(R ¹ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an amino group, a cyano group, a hydroxyl group, or a halogen atom, and R ² represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an amino group. , -CONHR ^5, or an -COOR ^{5, R 5} represents a hydrogen atom, or an alkyl group having 1 to 4 carbon atoms.)
[2] The method for producing a toner according to [1], wherein the colored particle dispersion contains a compound B represented by the following general formula (2).

(R ³ is an alkyl group having 1 to 8 carbon atoms, or an optionally substituted phenyl group, R ⁴ is a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an amino group, or a nitro group. Represents.)
[3] The toner production method according to [2], wherein the mass ratio of compound A to compound B (compound A / compound B) in the toner is 0.11 or more and 1.50 or less.
[4] The method for producing a toner according to any one of [1] to [3], wherein the total amount of the colorant in the toner is 4 to 10 parts by mass with respect to 100 parts by mass of the whole toner.
[5] The method for producing a toner according to any one of [1] to [4], wherein a glass transition point Tg of the resin fine particles in the resin fine particle dispersion is 37.0 to 55.0 ° C.
[6] The ratio D1 / D2 of the dispersed particle size D1 of the resin fine particle dispersion and the dispersed particle size D2 of the colored particle dispersion is 0.6 or more and 1.4 or less, [1] to [1] 5] The toner production method according to any one of [5].

  According to the present invention, it is possible to provide a method for producing a toner for developing an electrostatic image having excellent storage stability and chargeability under high temperature and high humidity while maintaining low temperature fixability. In addition, the electrostatic latent image developing toner obtained by the production method of the present invention reduces image bleeding when printed on a medium such as cloth, and the electrostatic charge is less likely to be damaged even after repeated washing. An image developing toner can be provided.

  Hereinafter, the present invention will be described in detail, but the present invention is not limited to the following embodiments, and can be arbitrarily modified without departing from the gist of the present invention. Hereinafter, the “electrostatic image developing toner” may be simply abbreviated as “toner”. The toner before the external additive is fixed or adhered is referred to as “toner mother particles”.

<About the present invention>
One aspect of the present invention includes a step of dispersing resin fine particles in a solvent to produce a resin fine particle dispersion, a step of dispersing colored particles in a solvent to produce a colored particle dispersion, and at least the resin fine particle dispersion. A step of forming toner base particles by mixing the color particle dispersion in water, a step of washing the toner base particles, and a step of applying an external additive to the toner base particles, A toner production method including at least a compound A represented by the following general formula (1).

(R ¹ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an amino group, a cyano group, a hydroxyl group, or a halogen atom, and R ² represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an amino group. , -CONHR ^5, or an -COOR ^{5, R 5} represents a hydrogen atom, or an alkyl group having 1 to 4 carbon atoms.)

[Process for producing resin fine particle dispersion]
A resin fine particle dispersion can be prepared by mixing a binder resin and a solvent (wet dispersion medium). The resin fine particle dispersion is prepared by dissolving the binder resin in a solvent, mixing the solution with a dispersant and a dispersion medium, stirring the mixture of the binder resin and the additive, and emulsifying the mixture. A uniform resin fine particle dispersion can be produced by a method such as emulsion polymerization in which a monomer and a polymerization initiator are dropped into a mixed aqueous solution of an agent and water. In order to uniformly aggregate with the colorant particles, a dispersant or a polymer dispersant used in the colorant dispersion may be used as the dispersant for the resin fine particle dispersion. The volume average particle size of the resin fine particles is preferably 0.02 μm or more, and from the viewpoint of controlling the aggregation rate, more preferably 0.05 μm or more, still more preferably 0.1 μm or more, preferably 3 μm or less. From the viewpoint, it is more preferably 2 μm or less, and still more preferably 1 μm or less.

[Process for producing colored particle dispersion]
A colorant dispersion can be prepared by mixing a colorant and a wet dispersion medium. Mixing can be performed using a dispersing device, and examples thereof include a dispersing device such as a rotary shearing homogenizer, a ball mill, a sand mill, a dyno mill, a media type dispersing machine, an ultrasonic dispersing machine, and a high-pressure impact dispersing machine. Which disperser is used can be appropriately selected according to the type of the colorant. For example, a pigment premix solution in which a colorant, a surfactant, and water are predispersed is prepared, and the premix solution is put into a wet bead mill filled with zirconia beads, and the disperser passes until a predetermined particle size is obtained. It is possible to disperse while adjusting the number of times.

  The wet dispersion medium is a liquid having a function of dispersing and holding the colorant particles, and is appropriately set according to the application purpose of the obtained colorant dispersion. Specifically, water; alcohols such as methanol, ethanol, propanol and butanol; organic solvents such as acetone, methyl ethyl ketone, tetrahydrofuran, toluene and xylene; monomers such as styrene, butyl acrylate, 2-ethylhexyl acrylate and acrylic acid These are used alone or in combination. Since the aggregation process in the case of the emulsion aggregation polymerization toner is carried out in an aqueous system, water may be selected as the wet dispersion medium.

  A colorant dispersion having a narrow particle size distribution by wet dispersion is optimal for use as a colorant dispersion added to polymer primary particles in an emulsion polymerization aggregation method toner. In that case, the wet dispersion medium is preferably water. The water quality is also related to the coarsening due to reaggregation of the colorant particles in the colorant dispersion, and if there are many impurities and the electrical conductivity is high, the dispersion stability with time tends to deteriorate. It is preferable to use ion-exchanged water or distilled water that has been desalted to 10 μS / cm or less, more preferably 5 μS / cm or less. The conductivity can be measured using a conductivity meter (a personal SC meter model SC72 and a detector SC72SN-11 manufactured by Yokogawa Electric Corporation).

  When water is used as the wet dispersion medium, a surfactant and / or a polymer dispersant is added to the water in order to wet and disperse the colorant particles and to keep the dispersion state stable. It is preferable. Examples of surfactants that can be used include anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap, cationic surfactants such as amine salts and quaternary ammonium salts, Nonionic surfactants such as polyethylene glycol, alkylphenol ethylene oxide adducts, and polyhydric alcohols can be used. Among these, anionic surfactants such as anionic surfactants and cationic surfactants are preferable. The nonionic surfactant is preferably used in combination with the anionic surfactant or the cationic surfactant. The above surfactants may be used alone or in combination of two or more.

[Step of forming toner base particles]
The resin fine particle dispersion and the colored particle dispersion can be mixed in water to form toner base particles through the following [aggregation step] and [aging step]. From the viewpoint of pigment dispersibility, the ratio D1 / D2 of the dispersed particle diameter D1 of the resin fine particle dispersion and the dispersed particle diameter D2 of the colored particle dispersion is 0.6 or more, preferably 0.7 or more. 1.4 or less, preferably 1.3 or less. The dispersed particle diameter of the resin fine particle dispersion can be adjusted by increasing or decreasing the amount of the surfactant added when preparing the resin fine particles by emulsion polymerization. When the amount of the surfactant is increased, the resin particles have a small particle size, and when the amount of the surfactant is decreased, the resin particles have a large particle size. The dispersion diameter of the colorant particles can be adjusted by the number of passes of the bead mill disperser when preparing the dispersant.

[Aggregation process]
In the aggregation step in the emulsion polymerization aggregation method, the binder resin (sometimes referred to as resin fine particles), the colorant particles, and optionally the charge control agent, the wax and other compounding components are mixed simultaneously or sequentially. A dispersion of each component, that is, a resin fine particle dispersion, a colorant particle dispersion, a charge control agent dispersion, and a wax fine particle dispersion are prepared in advance.

As a method for blending the colorant in the emulsion polymerization aggregation method, after preparing the resin fine particle dispersion, the colorant dispersion is added dropwise at a constant speed with a pump. At this time, the flow rate of the pump is adjusted to control the addition time of the colorant dispersion. Thereafter, this is aggregated to form particle aggregates. The colorant is preferably used in the state of being emulsified in water by a mechanical means such as a sand mill or a bead mill in the presence of an emulsifier. The blend of the colorant dispersion at the time of emulsion aggregation is calculated and used so as to be 2 to 15% by mass in the finished toner base particles after aggregation. The resin fine particle dispersion is mixed with 30 to 80% by weight of the total amount of the colorant dispersion and subjected to the aggregation treatment described below, and the target particle size is 0.5 to 0.95 times the size. It is preferable to add the remaining 20 to 70% by mass of the colorant dispersion when the grown particles become. In addition, the colorant dispersion can be added dropwise at a constant rate with a pump.

  The aggregating treatment usually includes a heating method, a method of adding an electrolyte, a method of combining these, and the like in a stirring tank. When the primary particles of the resin fine particles are aggregated with stirring to obtain a particle aggregate that is almost the size of the toner, the particle size of the particle aggregate is determined from the balance between the cohesive force between the particles and the shearing force by stirring. Although controlled, the cohesive force can be increased by heating or adding electrolyte.

When aggregation is performed by adding an electrolyte, both an organic salt and an inorganic salt can be used as the electrolyte. Specific examples of the electrolyte include NaCL, KCL, LiCL, Na ₂ SO ₄ , K ₂ SO ₄ , Li ₂ SO ₄ , MgCL ₂ , CaCL ₂ , MgSO ₄ , CaSO ₄ , ZnSO ₄ , and Al ₂ (SO ₄ ). ₃ , Fe ₂ (SO ₄ ) ₃ , CH ₃ COONa, C ₆ H ₅ SO ₃ Na, and the like. Of these, inorganic salts having a divalent or higher polyvalent metal cation are preferred. The blending amount of the electrolyte varies depending on the kind of the electrolyte, the target particle size, etc., but is usually 0.05 to 25 parts by mass with respect to 100 parts by mass of the solid component of the mixed dispersion, from the viewpoint of controlling the particle size. The amount is preferably 0.1 to 15 parts by mass, and more preferably 0.1 to 10 parts by mass. Here, as a method of controlling the particle size of the toner base particles in a specific range, a method of suppressing the blending amount of the electrolyte may be employed. Moreover, 20-70 degreeC is preferable and, as for the aggregation temperature in the case of performing aggregation by adding electrolyte, 30-60 degreeC is more preferable.

The time required for agglomeration is optimized depending on the shape of the apparatus and the processing scale, but in order to reach the target particle size, the toner base particles are usually held at a temperature within the above range for at least 30 minutes. It is preferable. The temperature rise until reaching the predetermined temperature may be raised at a constant rate, or may be raised stepwise.
If necessary, a resin fine particle dispersion is added to the above-mentioned particle aggregate after the aggregation treatment, and the resin fine particles are adhered or fixed to the particle aggregate to form core mother toner particles. When the charge control agent is added after the aggregation treatment, it is preferable to add the resin fine particles after adding the charge control agent to the dispersion containing the particle aggregate.

[Aging process]
In the emulsion polymerization aggregation method, in order to increase the stability of the particle aggregate obtained by aggregation, an emulsifier and a pH adjuster are added as a dispersion stabilizer to reduce the cohesive force between the particles, thereby growing the toner base particles. It is preferable to add an aging step for causing fusion between the agglomerated particles after stopping.
The manufactured toner preferably has a sharp particle size distribution. As a method for controlling the particle size within a specific range, the stirring rotation speed is reduced before the step of adding an emulsifier or a pH adjuster in the aging step, that is, And a method of reducing the shearing force by stirring.

In the ripening step, the viscosity of the binder resin is lowered by heating to be circularized, but if heated as it is, the growth of the toner base particle size does not stop, so for the purpose of stopping the particle size growth by heating, usually as a dispersion stabilizer It is possible to apply a shearing force by adding an emulsifier or a pH adjuster or increasing the number of stirring revolutions.
Even before the step of adding the dispersion stabilizer, a toner having a specific particle size distribution can be obtained even if the stirring rotational speed is lowered to reduce the shearing force to the aggregated particles. However, in consideration of the point that the amount of the dispersion stabilizer can be adjusted, it is preferable to perform it before the step of adding the dispersion stabilizer.

  The temperature of the aging step is preferably not less than Tg of the binder resin constituting the primary particles, more preferably not less than 5 ° C higher than the Tg, and preferably not more than 80 ° C higher than the Tg, more preferably The temperature is 50 ° C. or higher than the Tg. The time required for the aging step varies depending on the shape of the target toner, but after reaching the glass transition temperature of the polymer constituting the primary particles, usually 0.1 to 10 hours, preferably 1 to 6 hours. It is preferable to hold.

  In the emulsion polymerization aggregation method, it is preferable to add an emulsifier or raise the pH value of the aggregation liquid after the aggregation process, preferably before or during the aging process. As the emulsifier used here, one or more emulsifiers that can be used when producing polymer primary particles to be described later can be selected and used. It is preferable to use the same emulsifier.

  The blending amount in the case of blending the emulsifier is not limited, but is preferably 0.1 parts by weight or more, more preferably 1 part by weight or more, further preferably 3 parts by weight or more with respect to 100 parts by weight of the solid component of the mixed dispersion. Moreover, it is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and still more preferably 10 parts by mass or less. After the aggregation process, before the completion of the ripening process, by adding an emulsifier or by increasing the pH value of the flocculation liquid, aggregation of the particle aggregates aggregated in the aggregation process can be suppressed. The generation of coarse particles in the toner can be suppressed.

  By such a heat treatment, the primary particles of the resin fine particles in the aggregate are fused and integrated, and the shape of the toner base particles as the aggregate is close to a sphere. The particle aggregate before the aging step is considered to be an aggregate due to electrostatic or physical aggregation of the primary particles, but after the aging step, the polymer primary particles constituting the particle aggregate are fused together. In addition, the shape of the toner base particles can be made nearly spherical. According to such a ripening step, by controlling the temperature and time of the ripening step, a cocoon shape in which primary particles are aggregated, a potato type in which fusion has progressed, a spherical shape in which fusion has further progressed, etc. Various shapes of toner can be produced according to the purpose.

The particle aggregate obtained through each of the above steps is subjected to solid / liquid separation according to a known method, the particle aggregate is recovered, then washed as necessary, and then dried. Toner mother particles can be obtained.
Further, an outer layer mainly composed of a polymer is further formed on the surface of the particles obtained by the emulsion polymerization aggregation method by, for example, a spray drying method, an in-situ method, or a submerged particle coating method. It is also possible to obtain encapsulated toner base particles by forming them with a thickness of preferably 0.01 to 0.5 μm.

<Configuration of toner>
The toner can contain at least a binder resin, a colorant, and a wax.

[Binder resin]
The binder resin may be appropriately selected from those known to be usable for toner. For example, styrene resin, vinyl chloride resin, rosin modified maleic acid resin, phenol resin, epoxy resin, saturated or unsaturated polyester resin, polyethylene resin, polypropylene resin, ionomer resin, polyurethane resin, silicone resin, ketone resin, Ethylene-acrylate copolymer, xylene resin, polyvinyl butyral resin, styrene-acrylic copolymer such as styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene -A butadiene copolymer, a styrene-maleic anhydride copolymer, etc. can be mentioned. These resins can be used alone or in combination. A styrene-acrylic copolymer resin or a polyester resin is preferred.

[Resin fine particles]
The structure of the resin fine particles is not particularly limited, and examples thereof include physical particles of the binder resin and polymer primary particles obtained by polymerization reaction control for producing the binder resin. It is preferable that The binder resin in the resin fine particles may contain a polar monomer in order to improve dispersion stability and facilitate adjustment of the particle shape and particle diameter in the aggregation process. Specific examples include monomers having acidic groups such as carboxylic acid groups and sulfonic acid groups, monomers having basic groups such as amine groups and quaternary ammonium bases, and monomers having hydroxyl groups. The proportion of the total amount of polar monomers in 100% by mass of the total polymerizable monomer constituting the binder resin in the resin fine particles is preferably 0.5% by mass or more, more preferably 0.85% by mass or more, and still more preferably. Is 1.0 mass% or more. Moreover, Preferably it is 3.0 mass% or less, More preferably, it is 2.0 mass% or less. When it is in the above range, the dispersion stability of the obtained resin fine particles is improved, and it becomes easy to adjust the particle shape and particle diameter in the aggregation process. The Tg of the resin fine particles by DSC measurement is preferably 37.0 ° C. or higher, more preferably 40.0 ° C. or higher. Moreover, 55.0 degreeC or less is preferable and 49.5 degreeC or less is more preferable.

[Polymer primary particles]
The polymer primary particles are used in the aggregation step in a state of being dispersed in a solvent such as water. There are several methods for preparing the polymer primary particle dispersion. Polymer primary particles containing a styrene or (meth) acrylic monomer as a constituent element are emulsion-polymerized using an emulsifier with a styrene or (meth) acrylic monomer and, if necessary, a chain transfer agent. As a result, a polymer primary particle dispersion can be obtained.

  What is necessary is just to use suitably the 1 type (s) or 2 or more types of polymerizable monomer which can superpose | polymerize by the emulsion polymerization method as binder resin which comprises the polymer primary particle used for an emulsion polymerization aggregation method. At this time, each polymerizable monomer may be added separately, or a plurality of polymerizable monomers may be mixed in advance and added simultaneously. Furthermore, it is also possible to change the polymerizable monomer composition during the addition of the polymerizable monomer. Further, the polymerizable monomer may be added as it is, or may be added as an emulsion prepared by mixing with water or an emulsifier in advance.

  Among the polymerizable monomers, monomers having an acidic group, particularly (meth) acrylic acid, should be included. The ratio of the total amount of monomers having acidic groups in 100% by mass of all polymerizable monomers constituting the binder resin as the polymer primary particles is preferably 0.05% by mass or more, more preferably 0.3% by mass. % Or more, particularly preferably 0.5% by mass or more, and further preferably 1% by mass or more. Further, it is preferably 10% by mass or less, more preferably 5% by mass or less, and particularly preferably 2% by mass or less. When it is in the above range, the dispersion stability of the obtained polymer primary particles is improved, and the particle shape and particle diameter can be easily adjusted in the aggregation step.

Other monomers include styrenes such as styrene, methyl styrene, chlorostyrene, p-tert-butyl styrene, pn-butyl styrene, pn-nonyl styrene, methyl acrylate, ethyl acrylate, propyl acrylate Acrylates such as n-butyl acrylate, isobutyl acrylate, hydroxyethyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methacrylic acid Methacrylic acid esters such as hydroxyethyl and ethylhexyl methacrylate, acrylamide, N-propylacrylamide, N, N-dimethylacrylamide, N, N-dipropylacrylamide, N, N-dibutylacrylic Bromide, and amides of acrylic acid and the like. A polymerizable monomer may be used independently and may be used in combination of multiple.

  Moreover, among the above-described polymerizable monomers used in combination, as a preferred embodiment, an acidic monomer and other monomers may be used in combination. More preferably, (meth) acrylic acid is used as the acidic monomer, and a polymerizable monomer selected from styrenes and (meth) acrylic acid esters is used as the other monomer. It is preferable to use (meth) acrylic acid as the monomer, and use a combination of styrene and (meth) acrylic acid esters as the other monomer, and particularly preferably use (meth) acrylic acid as the acidic monomer and other monomers. As a combination of styrene and n-butyl acrylate.

  Furthermore, it is also preferable to use a crosslinked resin as the binder resin constituting the polymer primary particles. In that case, a polyfunctional monomer having radical polymerizability is used as a crosslinking agent shared with the above polymerizable monomer. Examples of the multifunctional monomer include divinylbenzene, hexanediol diacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, neopentyl glycol acrylate, diallyl phthalate, and the like. Is mentioned. In addition, a polymerizable monomer having a reactive group in a pendant group such as glycidyl methacrylate, methylol acrylamide, acrolein or the like can be used as a crosslinking agent. Among them, radically polymerizable bifunctional monomers are preferable, and divinylbenzene and hexanediol diacrylate are particularly preferable.

  These crosslinking agents such as polyfunctional monomers may be used alone or in combination. When a crosslinked resin is used as the binder resin constituting the polymer primary particles, the blending ratio of the crosslinking agent such as a polyfunctional monomer in the total polymerizable monomer constituting the resin is preferably 0.005% by mass or more. More preferably, it is 0.1% by mass or more, more preferably 0.3% by mass or more, preferably 5% by mass or less, more preferably 3% by mass or less, and further preferably 1% by mass or less. Is preferred.

Known emulsifiers can be used for the emulsion polymerization, but one or more emulsifiers selected from cationic surfactants, anionic surfactants and nonionic surfactants are used in combination. be able to.
Examples of the cationic surfactant include dodecyl ammonium chloride, dodecyl ammonium bromide, dodecyl trimethyl ammonium bromide, dodecyl pyridinium chloride, dodecyl pyridinium bromide, hexadecyl trimethyl ammonium bromide and the like.

  Examples of the anionic surfactant include fatty acid soaps such as sodium stearate and sodium dodecanoate, sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and sodium lauryl sulfate. Nonionic surfactants include, for example, polyoxyethylene dodecyl ether, polyoxyethylene hexadecyl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl ether, polyoxyethylene sorbitan monooleate ether, monodecanoyl sucrose, etc. Is mentioned.

The amount of the emulsifier is usually 1 to 10 parts by mass with respect to 100 parts by mass of the polymerizable monomer, and these emulsifiers include, for example, partially or fully saponified polyvinyl alcohol such as saponified polyvinyl alcohol, hydroxy One type or two or more types of cellulose derivatives such as ethyl cellulose can be used in combination as a protective colloid.
Examples of the polymerization initiator include hydrogen peroxide; persulfates such as potassium persulfate; organic peroxides such as benzoyl peroxide and lauroyl peroxide; 2,2′-azobisisobutyronitrile; Azo compounds such as 2′-azobis (2,4-dimethylvaleronitrile); redox initiators and the like are used. One or more of them are usually used in an amount of about 0.1 to 3 parts by mass with respect to 100 parts by mass of the polymerizable monomer. Among them, it is preferable that at least part or all of the initiator is hydrogen peroxide or organic peroxides.

  Any of the polymerization initiators may be added to the polymerization system before, simultaneously with, or after the addition of the polymerizable monomer, and these addition methods may be combined as necessary. In the emulsion polymerization, a known chain transfer agent can be used as necessary. Specific examples of such a chain transfer agent include t-dodecyl mercaptan, 2-mercaptoethanol, diisopropylxanthogen, four Examples thereof include carbon chloride and trichlorobromomethane. The chain transfer agent may be used alone or in combination of two or more, and is usually used in a range of 5% by mass or less based on the total polymerizable monomer. Moreover, a pH adjuster, a polymerization degree adjuster, an antifoaming agent, etc. can be further mix | blended with a reaction system suitably.

In the emulsion polymerization, the polymerizable monomer is polymerized in the presence of a polymerization initiator, and the polymerization temperature is usually 50 to 120 ° C, preferably 60 to 100 ° C, and more preferably 70 to 90 ° C.
The volume average diameter (Mv) of the polymer primary particles obtained by emulsion polymerization is usually 0.02 μm or more, preferably 0.05 μm or more, more preferably 0.1 μm or more, and usually 3 μm or less, preferably 2 μm or less. More preferably, it is preferably 1 μm or less. When the particle size is less than the above range, it may be difficult to control the aggregation rate. When the particle size exceeds the above range, the particle size of the toner obtained by aggregation tends to be large, and a toner having a target particle size can be obtained. It can be difficult.

[Colorant]
As the colorant, the compound A represented by the general formula (1) can be used. Examples of the alkyl group having 1 to 4 carbon atoms of R ¹ , R ² , and R ⁵ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a t-butyl group. Examples of the halogen atom include chlorine, bromine, iodine and the like. From the viewpoints of dispersibility and color, R ¹ is preferably a cyano group and R ² is preferably —CONHCH ₃ . Other examples of the colorant that may be contained include arylid disazo acetoacetate C.I. I. Pigment Yellow 13 (PY13) and 17 (PY17), C.I. I. Pigment Yellow 180 (PY180), azomethine pigment C.I. I. Pigment Yellow 150 (PY150) and the like are mentioned, but from the viewpoint of light resistance, it is preferable to use Compound B represented by the following General Formula (2) together. By using Compound B in combination, the balance of compatibility of Compound A with water can be adjusted.

(R ³ is an alkyl group having 1 to 8 carbon atoms, or a phenyl group optionally having a substituent, R ^4.
Represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an amino group, or a nitro group. )
The substituent of the phenyl group which may have a substituent group R ^3, usually 1 to 20 carbon atoms is preferably 1-8 carbon atoms. Specific examples include an alkyl group, a hydroxyl group, and an ester group, and an alkyl group is preferable. Examples of the alkyl group having 1 to 8 carbon atoms of R ³ and R ⁴ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, hexyl group, cyclohexyl group, An isobutyl group etc. are mentioned. R ³ and R ⁴ are each preferably a methyl group from the viewpoint of color development. When the substituent is small, the hydrophilic group tends to appear on the surface of the dispersion diameter, so that the dispersion stability of the pigment is improved.

  The total amount of the colorant in the toner is preferably 4 parts by mass or more with respect to 100 parts by mass of the whole toner, and more preferably 5 parts by mass or more from the viewpoint of color developability. Moreover, 10 mass parts or less are preferable, and 9 mass parts or less are more preferable from a dispersible viewpoint. The mass ratio of compound A to compound B (compound A / compound B) in the toner is preferably 0.11 or more, and more preferably 0.42 or more. Moreover, it is preferable that it is 1.50 or less, and 1.00 or less is more preferable.

[wax]
It is preferable to add a wax for imparting releasability. Any wax can be used as long as it has releasability, and is not particularly limited. Specifically, olefin waxes such as low molecular weight polyethylene, low molecular weight polypropylene, and copolymer polyethylene; paraffin wax; ester waxes having a long-chain aliphatic group such as behenyl behenate, montanate ester, stearyl stearate; water Plant waxes such as soy castor oil and carnauba wax; ketones having long chain alkyl groups such as distearyl ketone; silicones having alkyl groups; higher fatty acids such as stearic acid; long chain aliphatic alcohols such as eicosanol; glycerin and pentaerythritol Examples include carboxylic acid esters or partial esters of polyhydric alcohols obtained from polyhydric alcohols such as polyhydric alcohols and long chain fatty acids; higher fatty acid amides such as oleic acid amides and stearic acid amides; low molecular weight polyesters and the like.

  In order to improve the fixability among these waxes, the melting point of the wax is preferably 30 ° C. or higher, more preferably 40 ° C. or higher, and particularly preferably 50 ° C. or higher. Moreover, 100 degrees C or less is preferable, 90 degrees C or less is still more preferable, and 80 degrees C or less is especially preferable. If the melting point is too low, the wax tends to be exposed and sticky after fixing, and if the melting point is too high, the fixability at low temperatures is poor. Furthermore, as the wax compound species, ester waxes obtained from aliphatic carboxylic acids and mono- or polyhydric alcohols are preferred, and ester waxes having 20 to 100 carbon atoms are preferred.

  The above waxes may be used alone or in combination. Further, the melting point of the wax compound can be appropriately selected depending on the fixing temperature for fixing the toner. The amount of the wax used is preferably 4 to 20 parts by mass, particularly preferably 6 to 18 parts by mass, and further preferably 8 to 15 parts by mass with respect to 100 parts by mass of the toner. In addition, when the volume median diameter (Dv50) of the toner is 7 μm or less, that is, when the toner has a small particle diameter, the exposure of the wax to the toner surface becomes extremely intense as the amount of the wax used increases. The storage stability of the toner is deteriorated. The toner of the present invention has a small particle size with a sharp particle size distribution that does not cause deterioration of the toner characteristics as compared with conventional toners even when the amount of wax used is large as in the above range. It is.

The wax may be contained in the resin fine particles. As a method of blending the wax in the emulsion polymerization aggregation method, a wax dispersion that has been previously emulsified and dispersed in water at a volume average diameter (Mv) of 0.01 to 2.0 μm, more preferably 0.01 to 0.5 μm, is obtained during emulsion polymerization. It is preferable to add, or to add in an aggregation process. In order to disperse the wax with a suitable dispersed particle diameter in the toner, it is preferable to add the wax as a seed during emulsion polymerization. By adding as a seed, polymer primary particles in which wax is encapsulated can be obtained, so that a large amount of wax does not exist on the toner surface, and deterioration of chargeability and heat resistance of the toner can be suppressed. The wax content in the polymer primary particles is preferably 4 to 30% by mass, more preferably 5 to 20% by mass, and particularly preferably 7 to 15% by mass.

[Charge control agent]
A charge control agent may be blended in the toner in order to impart charge amount and charge stability. Conventionally known compounds are used as the charge control agent. Examples thereof include hydroxycarboxylic acid metal complexes, azo compound metal complexes, naphthol compounds, naphthol compound metal compounds, nigrosine dyes, quaternary ammonium salts, and mixtures thereof. The blending amount of the charge control agent is preferably in the range of 0.1 to 5 parts by mass with respect to 100 parts by mass of the resin.

  When a charge control agent is contained in the toner in the emulsion polymerization aggregation method, the charge control agent is blended with a polymerizable monomer or the like at the time of emulsion polymerization, or is blended in the aggregation process with the polymer primary particles and the colorant. The blended primary particles, the colorant, and the like can be blended by a method such as blending after agglomeration to obtain an appropriate particle size as a toner. Of these, the charge control agent is preferably emulsified and dispersed in water using an emulsifier, and used as an emulsified dispersion having a volume average diameter (Mv) of 0.01 μm to 3 μm. The formulation of the charge control agent dispersion at the time of emulsion aggregation is calculated and used so as to be 0.1 to 5% by mass in the finished toner base particles after aggregation.

The volume average diameter (Mv) of resin fine particles, colorant-dispersed particles, wax-dispersed particles, charge-controlling agent-dispersed particles and the like in the dispersion is measured using a nanotrack by the method described in Examples, and the measurement is performed. Defined as a value.
In the toner, the average circularity measured by using a flow type particle image analyzer FPIA-3000 (manufactured by Malvern) is preferably 0.90 or more, more preferably 0.92 or more, and still more preferably 0.95. That's it. The closer to a sphere, the less the localization of the charge amount in the particles and the developability tends to be uniform, but since it is difficult to produce a perfect spherical toner, the average circularity is Preferably it is 0.995 or less, More preferably, it is 0.990 or less.

  At least one of the peak molecular weights in the gel permeation chromatography (hereinafter sometimes abbreviated as “GPC”) of the tetrahydrofuran (THF) soluble content of the toner is preferably 10,000 or more, more preferably 15,000. More preferably, it is 20,000 or more, preferably 100,000 or less, more preferably 80,000 or less, and still more preferably 50,000 or less. When the peak molecular weight is lower than the above range, the mechanical durability in the non-magnetic one-component development method may be deteriorated. When the peak molecular weight is higher than the above range, the low temperature fixability and the fixing strength are deteriorated. There is a case.

  The THF insoluble content of the toner is preferably 1% by mass or more, more preferably 2% by mass or more, and preferably 20% by mass or less, more preferably, when measured by a mass method by celite filtration. It is good that it is 10 mass% or less. If it is not within the above range, it may be difficult to achieve both mechanical durability and low-temperature fixability. The chargeability of the emulsion polymerization aggregation method toner may be positively charged or negatively charged. Control of the chargeability of the toner may include the selection and content of a charge control agent, the selection and blending amount of an external additive, etc. Can be adjusted by.

[External additives and toner]
In order to control fluidity and developability, the toner base particles may be blended with a known external additive on the surface of the toner base particles to form a toner. External additives include metal oxides and hydroxides such as alumina, silica, titania, zinc oxide, zirconium oxide, cerium oxide, talc and hydrotalcite, titanium such as calcium titanate, strontium titanate and barium titanate. Examples thereof include acid metal salts, nitrides such as titanium nitride and silicon nitride, carbides such as titanium carbide and silicon carbide, and organic particles such as acrylic resins and melamine resins. Among these, silica, titania, and alumina are preferable, and those that have been surface-treated with, for example, a silane coupling agent or silicone oil are more preferable. The average primary particle diameter is preferably in the range of 1 to 500 nm, more preferably in the range of 5 to 100 nm. It is also preferable to use a combination of a small particle size and a large particle size in the particle size range. The total amount of the external additive is preferably in the range of 0.05 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the toner base particles.

[Others]
The toner for developing an electrostatic image of the present invention is a magnetic two-component developer in which a carrier for conveying the toner to the electrostatic latent image portion by a magnetic force coexists, or a magnetic toner containing a magnetic powder in the toner. It may be used for either a component developer or a non-magnetic one-component developer that does not use magnetic powder as a developer. In order to express the effect of the present invention remarkably, it is particularly preferable to use as a developer for a non-magnetic one-component development system.

  When used as the magnetic two-component developer, the carrier that is mixed with the toner to form the developer is a known magnetic substance such as an iron powder type, ferrite type, or magnetite type carrier, or a resin coating on the surface thereof. Or a magnetic resin carrier can be used. As the carrier coating resin, generally known styrene resins, acrylic resins, styrene acrylic copolymer resins, silicone resins, modified silicone resins, fluorine resins, and the like can be used, but are not limited thereto. It is not a thing. The average particle size of the carrier is not particularly limited, but preferably has an average particle size of 10 to 200 μm. These carriers are preferably used in an amount of 5 to 100 parts by mass with respect to 1 part by mass of the toner.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In the following examples, “part” means “part by mass”.
First, each particle diameter, circularity, etc. were measured as follows.

<Medium diameter measurement (D50)>
The median diameter (D50) of the particles having a median diameter (D50) of less than 1 micron is obtained from Nikkiso Co., Ltd. model Microtrac Nanotrac 150 (hereinafter abbreviated as “Nanotrack”) and analysis software Microtrac Particle Analyzer Ver10.1.2-019EE. The method described in the instruction manual using the ion-exchange water having an electric conductivity of 0.5 μS / cm as the solvent, the solvent refractive index: 1.333, the measurement time: 120 seconds, and the number of measurements: 5 times. The average value was obtained. Other setting conditions were particle refractive index: 1.59, transparency: transmission, shape: true sphere, density: 1.04.

<Volume Median Particle Size Measurement (Dv50)>
The volume median particle size (Dv50) of the particles having a volume median particle size (Dv50) of 1 micron or more is obtained by using Multisizer III (aperture diameter 100 μm: hereinafter abbreviated as Multisizer) manufactured by Beckman Coulter, It was measured by isoton II as a dispersion medium and dispersed to a dispersoid concentration of 0.03%.

<Average circularity measurement>
The average circularity is determined by dispersing the dispersoid in a dispersion medium (Cell Sheath: Sysmex) at 5720-7140 / μl, and using a flow particle analyzer (FPIA 3000: Sysmex) to analyze the amount of HPF. It measured by HPF mode on 0.35 microliters and HPF detection amount 2000-2500 conditions.

<Mass average molecular weight (Mw)>
After the polymer primary particle dispersion and the additional particle dispersion were lyophilized to remove moisture, the THF-soluble component was measured by gel permeation chromatography (GPC) under the following conditions.
Apparatus: GPC apparatus HLC-8320 manufactured by Tosoh Corporation, column: TOSOH TSKgel
SuperHM-H (diameter 6 mm × length 150 mm × 2), solvent: THF, column temperature 40 ° C., flow rate 0.5 mL / min, sample concentration: 0.1% by mass, calibration curve: standard polystyrene

<Emulsion solid content concentration>
The emulsion solid content concentration was determined by evaporating water by heating a 2 g sample at 195 ° C. for 90 minutes using an infrared moisture meter FD-610 manufactured by Kett Science Laboratory.

[Example 1]
<Preparation of wax dispersion A1>
Ester wax 1 (manufactured by NOF Corporation, product name: WEP-3, catalog melting point 73 ° C., catalog acid value 0.1 mgKOH / g, catalog hydroxyl value 3 mgKOH / g or less) 30.00 parts (1440 g), decaglycerin deca as wax 0.24 parts of behenate (Mitsubishi Chemical Foods, Inc., product name: B100D, hydroxyl value 27, melting point 70 ° C.), 1.93 parts of a 20% aqueous solution of sodium dodecylbenzenesulfonate (hereinafter abbreviated as 20% DBS aqueous solution), desorption 67.83 parts of salt water was heated to 90 ° C. and mixed for 20 minutes in a CSTR type stirring layer equipped with a 45 ° C. inclined three-stage paddle blade. Next, while this dispersion was heated to 90 ° C., circulation emulsification was started under a pressure of 25 MPa using a valve homogenizer (manufactured by Gorin Co., Ltd., 15-M-8PA type), and the particle diameter was measured with Nanotrac. A wax dispersion A1 (emulsion solid content concentration = 31.2%) was prepared by dispersing until the unit diameter (D50) was 245 nm.

<Preparation of wax dispersion A2>
22.50 parts of ester wax 1, 7.50 parts of ester wax 2 (manufactured by NOF Corporation, product name: WEP-5, catalog melting point 82 ° C., catalog acid value 0.1 mgKOH / g, catalog hydroxyl value 3 mgKOH / g or less), (1080 g), wax dispersion A2 (emulsion solids content) in the same manner as A1, except that 0.24 parts of decaglycerin decabehenate, 1.93 parts of 20% DBS aqueous solution and 67.83 parts of demineralized water were used. Concentration = 31.1%).

<Adjustment of Colorant Dispersion P1>
In a stirrer vessel equipped with a propeller blade, 7 parts of compound A (R ¹ = CN R ² = CONHR ⁵ , R ⁵ = CH ₃ ) and 13 parts of compound B (R ³ = CH ₃ , R ⁴ = CH ₃ ), Preliminarily dispersed by adding 1 part of an aqueous sodium solution (hereinafter abbreviated as 20% DBS aqueous solution), 2.8 parts of a nonionic surfactant (Emulgen 120, manufactured by Kao Corporation) and 75 parts of ion-exchanged water having a conductivity of 2 μS / cm. Thus, a pigment premix solution was obtained. The premix solution was supplied as a raw slurry to a wet bead mill and dispersed. Note that zirconia beads (true density of 6.0 g / cm ³ ) having a diameter of 120 mmφ, a separator having a diameter of 60 mmφ, and a diameter of 50 μm were used as a dispersion medium. Since the effective internal volume of the stator is about 2 liters and the media filling volume is 1.4 liters, the media filling rate is 70%. When the rotational speed of the rotor is constant (the peripheral speed at the tip of the rotor is about 11 m / sec), the premix slurry is supplied from the supply port by a non-pulsating metering pump at a supply speed of about 40 liters / hr and reaches a predetermined particle size. The product was acquired from the outlet. In operation, the cooling water at about 10 ° C. was circulated from the jacket to obtain a colorant dispersion P1. The dispersion median diameter D50 of the pigment was 263 nm, and the solid content of the dispersion was 24.6%.

<Preparation of Colorant Dispersion P2>
A colored dispersion, except that the pigment was changed to 10 parts of compound A (R ¹ = CN R ² = CONHR ⁵ , R ⁵ = CH ₃ ) and 10 parts of compound B (R ¹ = CH ₃ , R ² = CH ₃ ) A colored dispersion P2 was prepared in the same manner as P1. The dispersion median diameter D50 of the pigment was 225 nm, and the solid content of the dispersion was 24.2%.

<Preparation of Colorant Dispersion P3>
A colored dispersion P3 was prepared in the same manner as the colored dispersion P1, except that the pigment was changed to 20 parts of compound A (R ¹ = CN R ² = CONHR ⁵ , R ⁵ = CH ₃ ). The dispersion median diameter D50 of the pigment was 213 nm, and the solid content of the dispersion was 24.2%.

<Preparation of Colorant Dispersion P4>
A colored dispersion P3 was prepared in the same manner as the colored dispersion P1, except that the pigment was changed to 20 parts of compound B (R1 = CH ₃ , R2 = CH ₃ ). The dispersion median diameter D50 of the pigment was 265 nm, and the dispersion solid content was 23.5%.

<Preparation of Colorant Dispersion P5>
A colored dispersion P5 was prepared in the same manner as the colored dispersion P1, except that the pigment was changed to 20 parts of Pigment Yellow PY74. The dispersion median diameter D50 of the pigment was 146 nm, and the solid content of the dispersion was 23.7%.

<Preparation of polymer primary particle dispersion B1>
In a reactor equipped with a stirrer, heating / cooling device, concentrating device, and raw material / auxiliary charging device, 34.7 parts of wax dispersion A1, 252 parts of demineralized water, 0.5% iron (II) sulfate heptahydrate 0.02 part of the aqueous solution was charged, and the temperature was raised to 90 ° C. under a nitrogen stream while stirring. Thereafter, the following mixture of monomers and emulsifier solution was added over 240 minutes while stirring was continued. The time when the addition of the monomer / emulsifier aqueous solution started to be added was set as the polymerization start, and the following initiator aqueous solution was added over 0 to 480 minutes from the start of the polymerization. The following iron sulfate aqueous solution was added 240 minutes after the start of polymerization. The temperature was raised to 95 ° C. 300 minutes after the start of polymerization. Heating and stirring were continued until 540 minutes from the start of polymerization.

[Monomers]
Styrene 70.9 parts Butyl acrylate 29.1 parts Acrylic acid 0.85 parts Trichlorobromomethane 1.0 part Hexanediol diacrylate 0.95 parts [Emulsifier aqueous solution]
20% DBS aqueous solution 1.0 part Demineralized water 66.9 parts [Initiator aqueous solution]
8% aqueous hydrogen peroxide solution 28.0 parts 8% L-(+) ascorbic acid aqueous solution 28.0 parts [iron sulfate aqueous solution]
0.5% iron (II) sulfate heptahydrate aqueous solution 0.08 part After completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle dispersion B1. The median diameter (D50) measured using the nanotrack was 239 nm. The weight average molecular weight (Mw) is 6700.
It was zero. Tg by DSC measurement was 51.2 ° C.

<Preparation of additional particle dispersion B2>
A reactor equipped with a stirrer, a heating / cooling device, a concentrator, and a raw material / auxiliary charging device was charged with 50.7 parts of wax dispersion A2, 3.5 parts of 20% DBS aqueous solution, and 349 parts of demineralized water, and stirred. The temperature was raised to 75 ° C. under a nitrogen stream.
Five minutes after adding the following initiator aqueous solution 1, the following mixture of monomers and emulsifier solution was added over 180 minutes while stirring was continued. The time when the addition of the monomer / emulsifier aqueous mixture was started was set as the polymerization start, and the following iron sulfate aqueous solution was added 180 minutes after the start of the polymerization. The temperature was raised to 93 ° C. 180 minutes after the start of polymerization. The following aqueous initiator solution 2 was added over 240 minutes to 60 minutes from the start of polymerization. The following initiator aqueous solution 3 was added over 120 minutes from 240 minutes from the start of polymerization. Heating and stirring were continued until 480 minutes from the start of polymerization.

[Monomers]
Styrene 97.9 parts Butyl acrylate 2.1 parts Acrylic acid 1.5 parts 1-Dodecanethiol 1.0 part [Emulsifier aqueous solution]
20% DBS aqueous solution 1.0 part demineralized water 66.7 parts [initiator aqueous solution 1]
20% ammonium persulfate aqueous solution 6.0 parts [initiator aqueous solution 2]
14.2 parts of 8% aqueous hydrogen peroxide solution [Initiator aqueous solution 3]
8% L-(+) ascorbic acid aqueous solution 21.3 parts [iron sulfate aqueous solution]
0.5% Iron (II) sulfate heptahydrate aqueous solution 0.05 part After completion of the polymerization reaction, the reaction mixture was cooled to obtain a milky white additional particle dispersion B2. The median diameter (D50) measured using the nanotrack was 112 nm. The weight average molecular weight (Mw) was 41000.

<Preparation of toner base particles C1>
In a mixer equipped with a stirrer, a heating / cooling device, and each raw material / auxiliary charging device, 86.2 parts of polymer primary particle dispersion B1 (solid content), 0.15 part of 20% DBS aqueous solution (solid content), 0.11 part (solid content) of 5% iron (II) sulfate heptahydrate aqueous solution and 7.0 parts of pigment dispersion P1 were sequentially added with stirring. The temperature was raised to an internal temperature of 45.8 ° C. over 130 minutes. Here, the volume-median particle size (Dv50) was measured using a multisizer and found to be 5.2 μm. 9.6 parts of polymer primary particle dispersion B1 (solid content) was added. After 30 minutes, 4.2 parts (solid content) of additional particle dispersion B2 was added. After 90 minutes, 4.1 parts (solid content) of 20% DBS aqueous solution and 23 parts of deionized water were added, and then the temperature was raised to 69 ° C. over 25 minutes and held for 54 minutes. Thereafter, it was cooled to 30 ° C.

  The obtained dispersion was extracted and suction filtered with an aspirator using 5 types C (No. 5C manufactured by Toyo Roshi Kaisha, Ltd.) filter paper. The cake remaining on the filter paper was transferred to a stainless steel container equipped with a stirrer (propeller blade), and ion-exchanged water having an electric conductivity of 1 μS / cm was added and stirred uniformly, and then stirred for 30 minutes. This process was repeated until the electric conductivity of the filtrate reached 2 μS / cm, and then the obtained cake was dried in a blow dryer set at 40 ° C. for 48 hours to obtain toner mother particles C1.

<Manufacture of toner D1>
Toner base particle C1 (100 parts), polymer / silica composite particles (ATLAS 100: manufactured by Cabot Corporation: silica / polymer ratio = 70/30, true specific gravity = 1.7 g / cm ³ , containing octahydropentalene) 4 parts, 0.5 part of titania and silica composite oxide particles (STX501: manufactured by Nippon Aerosil Co., Ltd.), 0.4 part of small particle size silica (RY200L: manufactured by Nippon Aerosil Co., Ltd.) are added, and 3000 rpm is added using a Henschel mixer. And then sieving with stirring for 15 minutes to obtain toner D1. The obtained toner had a volume median particle size of 5.76 μm and an average circularity of 0.975.

<Preparation of Toner D2>
Toner D2 was prepared in the same manner as toner D1, except that P2 was used instead of P1 as the pigment dispersion. The obtained toner had a volume-median particle size of 5.41 μm and an average circularity of 0.976.

<Preparation of Toner D3>
Toner D3 was prepared in the same manner as toner D1, except that P3 was used instead of P1 as the pigment dispersion. The obtained toner had a volume median particle size of 5.56 μm and an average circularity of 0.975.

<Preparation of Toner D4>
Toner D4 was prepared in the same manner as toner D1, except that P4 was used instead of P1 as the pigment dispersion. The obtained toner had a volume median particle size of 5.62 μm and an average circularity of 0.976.

<Preparation of Toner D5>
Toner D5 was prepared in the same manner as toner D1, except that P5 was used instead of P1 as the pigment dispersion. The obtained toner had a volume median particle size of 5.62 μm and an average circularity of 0.976.

<Blocking resistance>
10 g of developing toner is put into a cylindrical container having an inner diameter of 3 cm and a height of 6 cm, a load of 20 g is put on it, and left in an environment of a temperature of 50 ° C. and a humidity of 55% for 48 hours. The degree of aggregation was confirmed by applying a load.
◯: collapses with a load of 100 g or less Δ: collapses with a load exceeding 100 g and 200 g or less ×: does not collapse unless a load exceeding 200 g is applied

<Fixing test>
Using the commercially available printer with the fixing unit removed, the recording toner obtained was loaded with a developing roller with a printing speed of 16 ppm, a non-magnetic single component developing rubber roller, a metal blade, and a charging roller (PCR). An unfixed toner image having a toner adhesion amount of about 0.5 mg / cm ² was printed on (OKI Excellent White).

The hot roll fixing machine has a roller diameter of 27 mm, a nip width of 9 mm, a fixing speed of 229 mm / sec, a heater on the upper roller, and the roller surface made of PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer). Silicone oil is not applied. The surface temperature of the roller was decreased from 170 ° C. in increments of 5 ° C., and a recording paper carrying an unfixed toner image having an adhesion amount of about 0.5 mg / cm ² was conveyed to the fixing nip portion to obtain a fixed image.

<Low temperature fixability test by tape peeling>
A mending tape was affixed to the obtained fixed image, and a 2 kg weight was passed thereon to bring the tape and the fixed image into close contact. The mending tape was peeled off, and the degree to which the fixed image transferred to the tape was visually determined.
○: Fixing at 160 ° C. or less Δ: Fixing at over 160 ° C. and 170 ° C. ×: Not fixing at 170 ° C.

<Hot offset resistance test>
The surface temperature of the roller was increased from 175 ° C. in increments of 5 ° C., the recording paper carrying the unfixed toner image was conveyed to the fixing nip portion, and the state when discharged was observed.
○: No offset at 195 ° C. Δ: Offset at a temperature higher than 185 ° C. and lower than 195 ° C. x Offset at lower than 185 ° C.

<Color reproducibility evaluation and coloring degree evaluation>
As in the above fixing test, an unfixed toner image having a toner adhesion amount of about 0.5 mg / cm ² is printed on recording paper (OKI Excellent White), and the temperature of the fixing member is constantly controlled to be 170 ° C. And fixing at a fixing speed of 229 mm / sec to obtain a sample for evaluation.
The chromaticness index a * and b * in the L * a * b * color system (CIE: 1976) was measured for the formed solid image using a chromaticity meter (X-Rite 938, manufactured by X-Rite). The value of C * represented by the following formula (1) was determined, and the saturation of each color toner was evaluated.

C * = [(a *) 2+ (b *) 2] 1/2 Formula (1)
The evaluation criteria for saturation are as follows.
○: b * is 100 or more Δ: b * is 95 or more and less than 100 x: b * is less than 95

<Printing test on fabric>
Using the commercially available printer with a printing speed of 229 mm / sec, an organic photoreceptor charged with a developing rubber roller, a metal blade, and a charging roller (PCR) with a printing speed of 229 mm / sec, with the fixing unit removed, Printing was performed on the transfer sheet EA-CR (QuickArt) at a toner adhesion amount of about 0.3 mg / cm ² .

The transfer sheet was placed on the fabric and pressed at 175 ° C. for 15 seconds to transfer the image onto the fabric. The transferred image was observed with a microscope, and the degree of bleeding was visually determined.
○: Good. No blurring △: Somewhat bad. Characters can be judged but the outline is blurred.
X: Defect. The character cannot be determined.

<Washing resistance>
The fabric prepared by the above printing test was washed with the standard course of the fully automatic washing machine Mitsubishi AW42C1 and dried with the standard course of the dryer Toshiba ED45C. The color blur of the images before and after that was observed visually.
○: No change in the image before and after washing.
Δ: The outline of the image is blurred after washing.
X: The whole image fades after washing.

<Light resistance evaluation>
The obtained printed sample was subjected to a light resistance test. The light resistance evaluation was performed by placing the printed sample in the following weatherometer.
Atlas Ci4000 Xenon Weather Ometer (Toyo Seiki Seisakusho)
Test conditions: Black panel temperature 58 ° C
Inside the test chamber 33 ℃
Test humidity 50%
Illuminance 0.55W / m ² (340nm)
Outer filter; soda lime
Inner filter: borosilicate Image density of the printed sample before and after the light resistance test was measured to evaluate the light resistance of the toner. For the measurement of the image density, a spectrocolorimetric densitometer X-Rite 938 (light source D50) manufactured by X-Rite was used.
ΔE was calculated from the difference between the L value, a value, and b value before and after the test.

ΔE = [(a−a ₀ ) ^ 2 + (b−b ₀ ) ^ 2 + (L−L ₀ ) ^ 2] ^ (1/2)
... Formula (2)
○: Very good. ΔE is 2.0 or less in a light resistance test of 500 hrs or more. Δ: Good. ΔE is larger than 2.0 and not larger than 4.0 in the light resistance test of 500 hrs or more.
X: Defect. ΔE is greater than 4.0 after the light resistance test is 500 hrs or more.

Claims (6)

A step of dispersing resin fine particles in a solvent to produce a resin fine particle dispersion;
A step of dispersing colored particles in a solvent to prepare a colored particle dispersion;
A step of mixing at least the resin fine particle dispersion and the colored particle dispersion in water to form toner base particles;
Cleaning the toner base particles;
Adding an external additive to the toner base particles,
A method for producing a toner, wherein the colored particle dispersion contains at least a compound A represented by the following general formula (1).

(R ¹ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an amino group, a cyano group, a hydroxyl group, or a halogen atom, and R ² represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an amino group. , -CONHR ^5, or an -COOR ^{5, R 5} represents a hydrogen atom, or an alkyl group having 1 to 4 carbon atoms.) The method for producing a toner according to claim 1, wherein the colored particle dispersion contains a compound B represented by the following general formula (2).

(R ³ is an alkyl group having 1 to 8 carbon atoms, or an optionally substituted phenyl group, R ⁴ is a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an amino group, or a nitro group. Represents.)   The toner production method according to claim 2, wherein a mass ratio of the compound A to the compound B (compound A / compound B) in the toner is 0.11 or more and 1.50 or less.   The method for producing a toner according to any one of claims 1 to 3, wherein the total amount of the colorant in the toner is 4 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the whole toner.   The method for producing a toner according to any one of claims 1 to 4, wherein a glass transition point Tg of the resin fine particles in the resin fine particle dispersion is 37.0 to 55.0 ° C.   The ratio D1 / D2 of the dispersed particle size D1 of the resin fine particle dispersion and the dispersed particle size D2 of the colored particle dispersion is 0.6 or more and 1.4 or less. The method for producing a toner according to any one of the above items.