JP5973908B2 - Method for producing toner for developing electrostatic image - Google Patents

Description

  The present invention relates to a method for producing an electrostatic charge image developing toner.

  In recent years, in the field of toner for electrophotography, with the development of an electrophotographic system, development of a toner corresponding to high image quality and high speed has been demanded. From the viewpoint of high image quality, it is necessary to reduce the particle size of the toner. Instead of the conventional melt-kneading method, a chemical method such as a suspension polymerization method, an emulsion polymerization method, or a dissolution suspension method is used. A method of obtaining is disclosed. Furthermore, from the viewpoint of speeding up, a chemical toner having a release agent added therein has been reported to improve low-temperature fixability.

For example, Patent Document 1 discloses (1) a mold release agent (A) and a mold release agent (B) having a melting point 5 ° C. higher than the melting point of the mold release agent (A) in an aqueous medium. A method for producing a toner is disclosed which includes a step of emulsifying in the presence of an acid salt to obtain release agent particles, and (2) a step of aggregating and coalescing the obtained release agent particles and resin particles. As an effect of the production method, aggregation control with a small particle size at the time of toner production, that is, agglomerated particles having a sharp particle size distribution can be generated, and a toner having no release agent can be produced during the coalescence process. In addition, it is described that an electrophotographic toner having excellent low-temperature fixability and hot offset resistance, that is, excellent fixability and storage stability can be obtained.
Patent Document 2 discloses a toner release agent dispersion containing a release agent and a dibasic acid having an alkyl group and / or an alkenyl group or a salt thereof, wherein at least one acid group of the dibasic acid is used. A toner release agent dispersion in which is a carboxyl group is disclosed. As an effect of the release agent dispersion for the toner, it is described that the toner has good emulsification performance and emulsification stability and can impart excellent productivity, durability and low-temperature fixability of the toner.

In Patent Document 3, in a toner for an electrostatic latent image developer composed of a binder resin and a colorant, the toner contains a specific amount of wax, the amount of wax exposed on the toner surface, and the number average of the wax Toner for electrostatic latent image developer characterized by having a dispersion diameter in a specific range is required for oilless fixability, powder characteristics of toner using wax, filming property, and color image. There is a disclosure that high transferability is compatible at a high level.
Patent Document 4 discloses a toner for developing an electrostatic image obtained by aggregating wax particles, binder particles and colorant particles in an aqueous medium, and thermally fusing the obtained aggregates, wherein the wax particles include: The binder particles are prepared by emulsifying and dispersing a wax containing an ester component in a specific ratio and having a penetration of 4 or less in an aqueous medium, and after being agglomerated at a temperature not higher than the melting temperature of the wax. A toner obtained by fusing at a temperature 25 ° C. or more higher than the glass transition temperature of the polymer constituting the toner is disclosed. As the effect of the toner, it has good releasability, excellent offset resistance and low-temperature fixability, has a sharp particle size distribution, has little contamination to carriers, photoreceptors, developing sleeves, etc. It is described that a good, high-quality visible image can be stably formed over a long period of time.

International Publication No. 2011/074580 JP 2008-33139 A JP-A-10-207116 JP 2000-98654 A

When a toner is manufactured by a chemical method, unlike the melt-kneading and pulverizing method, there is no kneading step, and thus dispersibility of the release agent in the toner becomes a problem. Therefore, in the chemical method, a surfactant is used when the release agent is dispersed in an aqueous medium. However, when a surfactant is used, although the dispersion stability of the release agent is improved, the release agent is released from the toner particles in the step after the release agent is aggregated with the resin particles in an aqueous medium, particularly in the fusing step. The agent is easily detached and the release agent is easily exposed on the surface of the toner particles. For this reason, the obtained toner has a problem in that sufficient fixability cannot be obtained, adhesion to a developing device occurs, and durability is lowered.
An object of the present invention is to provide a method for producing a toner for developing an electrostatic charge image, in which release of a release agent and exposure are suppressed, and a toner excellent in fixability and durability can be obtained.

When dispersing the release agent in an aqueous medium, the present inventor does not particularly use a dispersant such as a surfactant by adjusting the pH to a specific range using a specific amount of ester wax. In addition, the release agent dispersion can be prepared, and the release agent can be detached from the toner particles in the toner manufacturing process and the toner obtained by producing a toner by a chemical method using the release agent dispersion. It was found that the surface exposure of the release agent in can be suppressed.
That is, the present invention relates to a method for producing an electrostatic image developing toner including the following steps (1) to (3).
Step (1): A release agent (a) containing an ester wax (a1) having an acid value of 1 mgKOH / g to 10 mgKOH / g and a release agent (a2) other than the ester wax (a1), pH 9. 5 to 14 and under conditions where no surfactant is added or the surfactant content is 0.5 parts by mass or less with respect to 100 parts by mass of the total amount of the release agent (a). Step (2) of preparing release agent particles by dispersing: Step of obtaining aggregated particles by mixing the release agent particles, resin particles, and flocculant obtained in step (1) in an aqueous medium. (3): a step of fusing the aggregated particles obtained in step (2) to obtain fused particles

  According to the present invention, it is possible to provide a method for producing a toner for developing an electrostatic charge image, in which release of a release agent and exposure are suppressed, and a toner excellent in fixability and durability can be obtained.

[Toner Production Method]
The toner production method of the present invention includes the following steps (1) to (3).
Step (1): A release agent (a) containing an ester wax (a1) having an acid value of 1 mgKOH / g to 10 mgKOH / g and a release agent (a2) other than the ester wax (a1), pH 9. 5 to 14 and under conditions where no surfactant is added or the surfactant content is 0.5 parts by mass or less with respect to 100 parts by mass of the total amount of the release agent (a). Step (2) of preparing release agent particles by dispersing: Release agent particles, resin particles (A), and aggregating agent obtained in step (1) are mixed in an aqueous medium to form agglomerated particles. Step of obtaining (3): Step of fusing the aggregated particles obtained in step (2) to obtain fused particles. Step (2) may also include the following steps (2A) and (2B). Good.
Step (2A): Step (2B): Step of obtaining aggregated particles (1) by mixing the release agent particles, resin particles (A), and the flocculant obtained in step (1) in an aqueous medium. A step of adding the resin particles (B) to the aggregated particles (1) obtained in (2A) at a time or divided into a plurality of times to obtain the aggregated particles (2) formed by adhering the resin particles (B). In addition, when implementing a process (2A) and a process (2B), the "aggregated particle obtained at the process (2)" in a process (3) means "the aggregated particle obtained at the process (2B) ( 2) ". In addition, when step (2A) is performed and step (2B) is not performed, “aggregated particles obtained in step (2)” in step (3) is “obtained in step (2A)”. It means “aggregated particles (1)”.

Although the detailed mechanism by which the toner excellent in fixability and durability can be obtained by the production method of the present invention is not clear, it can be considered as follows.
In step (1), the release agent (a) contains an ester wax (a1) having a specific range of acid values, and the pH in the dispersion system obtained by dispersing the release agent (a) is set to a specific range. By adjusting the hydrophilicity of the ester wax (a1), the release agent (a) can be dispersed together with the release agent (a2) other than the ester wax (a1) without using any surfactant. It is thought that it will be possible. In addition, since the ester wax (a1) has good compatibility with the resin and does not use a surfactant, the release agent particles obtained in the step (1) are used as resin particles in the step (2). It is considered that the release agent (a) is less likely to be detached even after being agglomerated, and as a result, the fixability and durability of the toner are improved.

<Step (1)>
Step (1) in the toner production method of the present invention comprises an ester wax (a1) having an acid value of 1 mgKOH / g to 10 mgKOH / g and a release agent (a2) other than the ester wax (a1). The mold agent (a) has a pH of 9.5 to 14, and the surfactant is not added or the surfactant content is 0.5 parts by mass with respect to 100 parts by mass of the total amount of the release agent (a). This is a step of preparing release agent particles by dispersing in an aqueous medium under the following conditions.

[Releasing agent particles]
In the present invention, the release agent particles are obtained as a dispersion of release agent particles by dispersing the release agent in an aqueous medium.

(Release agent (a))
The release agent (a) in the present invention has an acid value of 1 mgKOH / from the viewpoint of improving the dispersion stability of the release agent particles, from the viewpoint of widening the fixable temperature range of the obtained toner, and from the viewpoint of improving the durability. g and 10 mg KOH / g or less of the ester wax (a1) and a release agent (a2) other than the ester wax (a1).

(Ester wax (a1))
In the present invention, the ester wax (a1) refers to a wax having an ester bond and having an acid value of 1 mgKOH / g or more and 10 mgKOH / g or less.
The acid value of the ester wax (a1) is 1 mgKOH / g or more from the viewpoint of improving the dispersion stability of the release agent particles, from the viewpoint of widening the fixable temperature range of the obtained toner, and from the viewpoint of improving the durability. , Preferably 2 mgKOH / g or more, more preferably 3 mgKOH / g or more, and 10 mgKOH / g or less, preferably 8 mgKOH / g or less, more preferably 7 mgKOH / g or less.
Examples of the ester wax (a1) include synthetic ester wax and natural ester wax. Examples of the synthetic ester wax include esters composed of a long-chain alcohol and a fatty acid, and preferably at least one fatty acid ester of behenyl behenate, stearyl stearate, and pentaerythritol. The natural ester wax is preferably at least one of carnauba wax and rice wax. Of these, carnauba wax is more preferable from the viewpoint of improving the dispersion stability of the release agent particles.
The melting point of the ester wax (a1) is preferably 100 ° C. or less, more preferably 95 ° C. or less, still more preferably 90 ° C. or less, from the viewpoint of widening the fixable temperature range of the toner and improving the low-temperature fixability. More preferably, it is 88 ° C. or lower, and from the viewpoint of improving the durability of the toner, it is preferably 60 ° C. or higher, more preferably 65 ° C. or higher, still more preferably 70 ° C. or higher, and even more preferably 75 ° C. or higher. .
In the present invention, the melting point of the release agent (a) is determined by the method described in the examples.
The content of the ester wax (a1) in the release agent (a) is preferably 1% by mass or more, more preferably 3% by mass or more, and still more preferably 5 from the viewpoint of improving the dispersion stability of the release agent particles. % By mass or more, more preferably 8% by mass or more, preferably 49% by mass or less, more preferably 40% by mass or less, still more preferably 30% by mass or less, and still more preferably 20% by mass or less. .

(Release agent (a2))
Examples of the release agent (a2) other than the ester wax (a1) include hydrocarbon wax, silicone wax, fatty acid amide, and ester wax having an acid value of less than 1 mgKOH / g or more than 10 mgKOH / g. Among these, it is preferable to contain a hydrocarbon wax from the viewpoint of widening the fixable temperature range of the toner and improving the low-temperature fixability and durability. Specific examples of the hydrocarbon wax include low-molecular-weight polyolefins such as polyethylene, polypropylene, and polybutene; and mineral / petroleum waxes such as ozokerite, ceresin, paraffin wax, microcrystalline wax, and Fischer-Tropsch wax. Among these, paraffin wax is more preferable from the viewpoint of widening the fixable temperature range of the toner and improving low-temperature fixability and durability.
The melting point of the release agent (a2) is preferably 100 ° C. or less, more preferably 95 ° C. or less, further preferably 90 ° C. or less, from the viewpoint of widening the fixable temperature range of the toner and improving the low-temperature fixability. More preferably, it is 80 ° C. or lower, and from the viewpoint of improving the durability of the toner, it is preferably 60 ° C. or higher, more preferably 63 ° C. or higher, still more preferably 65 ° C. or higher.
The mass ratio of the ester wax (a1) to the release agent (a2) [ester wax (a1) / release agent (a2)] is capable of fixing the obtained toner in terms of improving the dispersion stability of the release agent particles. From the viewpoint of widening the temperature range and improving the durability, it is preferably 1/99 to 49/51, more preferably 3/97 to 40/60, still more preferably 5/95 to 30/70, and still more preferably. 8/92 to 20/80.
The total content of the ester wax (a1) and the release agent (a2) in the release agent (a) is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass, and still more. Preferably it is 99 mass% or more, More preferably, it is substantially 100 mass%, More preferably, it is 100 mass%.

The melting point of the release agent (a) is preferably 100 ° C. or less, more preferably 95 ° C. or less, and still more preferably 90 ° C. or less from the viewpoint of widening the fixable temperature range of the toner and improving the low-temperature fixability. In view of improving the durability of the toner, the temperature is preferably 60 ° C. or higher, more preferably 63 ° C. or higher, and still more preferably 65 ° C. or higher.
It is preferable that both melting | fusing point of the said ester wax (a1) and a mold release agent (a2) are 60 degreeC or more and 100 degrees C or less. That is, the release agent (a) preferably contains at least two release agents having a melting point of 60 ° C. or higher and 100 ° C. or lower. The melting point of the release agent having the largest mass ratio among the release agents contained in the obtained toner is defined as the melting point of the release agent in the present invention. When all have the same ratio, the lowest value is set.

  The amount of the release agent (a) used is preferably 1 part by mass or more based on 100 parts by mass of the resin in the toner from the viewpoint of improving the releasability of the toner and widening the fixable temperature range. Preferably it is 2 mass parts or more, More preferably, it is 5 mass parts or more, Preferably it is 20 mass parts or less, More preferably, it is 15 mass parts or less, More preferably, it is 10 mass parts or less.

(Preparation of release agent particles)
In the step (1), the ester wax (a1) and the release agent (a2) having an acid value of 1 mgKOH / g or more and 10 mgKOH / g or less are used under conditions where no surfactant is present, or the surfactant content is Release agent particles are prepared by dispersing them in an aqueous medium at pH 9.5 or more and 14 or less under the condition of 0.5 parts by mass or less with respect to 100 parts by mass of the total amount of the release agent (a). For adjusting the pH, a basic compound can be used as necessary.
When the pH is 9.5 or more, the ester wax (a1) having an acid value of 1 mgKOH / g or more and 10 mgKOH / g or less is sufficiently hydrophilized, not only in the wax itself but also in the release agent (a). It contributes to the dispersion stability of the other components in the aqueous medium, and fine release agent particles can be prepared. From this viewpoint, the pH is preferably 10 or more, more preferably 11 or more, still more preferably 11.5 or more, and even more preferably 12 or more. From the viewpoint of sufficient suppression, it is preferably 13.5 or less, more preferably 13 or less, and still more preferably 12.5 or less.

The dispersion of the release agent particles is preferably obtained by dispersing the release agent and the aqueous medium using a disperser at a temperature equal to or higher than the melting point of the release agent. As the disperser to be used, a homogenizer, a high-pressure disperser, an ultrasonic disperser and the like are preferable, and an ultrasonic disperser is more preferable, from the viewpoint of widening the fixable temperature range of the obtained toner and improving durability. What is necessary is just to set dispersion | distribution time suitably with the disperser to be used.
Examples of the ultrasonic disperser include an ultrasonic homogenizer, and examples of commercially available devices include “US-600T” (manufactured by Nippon Seiki Co., Ltd.).
Moreover, it is preferable to preliminarily disperse the release agent, optionally a basic compound, and an aqueous medium in advance using a mixer such as a homomixer or a ball mill before using the disperser.

As the aqueous medium, those containing water as a main component are preferable. From the viewpoint of environmental properties and the viewpoint of improving the dispersion stability of the release agent particles, the water content in the aqueous medium is preferably 80% by mass or more, More preferably, it is 90 mass% or more, More preferably, it is 95 mass% or more, More preferably, it is substantially 100 mass%, More preferably, it is 100 mass%. As water, deionized water or distilled water is preferably used.
Components other than water in the aqueous medium include alkyl alcohols having 1 to 5 carbon atoms such as methanol, ethanol, isopropanol and butanol; dialkyl ketones having 1 to 3 carbon atoms such as acetone and methyl ethyl ketone; cyclic ethers such as tetrahydrofuran And an organic solvent that dissolves in water. Among these, alcohols having 1 to 5 carbon atoms, such as methanol, ethanol, isopropanol, and butanol, which are organic solvents that do not dissolve the resin, are preferable from the viewpoint of preventing the organic solvent from being mixed into the toner.

Examples of the basic compound include at least one of a metal hydroxide and an amine.
Examples of the metal hydroxide include lithium hydroxide, sodium hydroxide, and potassium hydroxide. Examples of the amine include ammonia, dimethylamine, triethylamine, diethanolamine and the like. Of these basic compounds, sodium hydroxide and potassium hydroxide are preferably used from the viewpoints of reducing the particle size of the release agent particles, widening the fixing temperature range of the toner, and improving durability. is there.

  In the present invention, a surfactant is added to the dispersion of the release agent particles in an aqueous medium from the viewpoint of improving the dispersion stability of the release agent particles and obtaining uniform agglomerated particles in the subsequent aggregation step. Or the surfactant content is 0.5 parts by mass or less with respect to 100 parts by mass of the total amount of the ester wax (a1) and the release agent (a2). Preferably, the surfactant is not added, that is, a release agent, optionally a basic compound is used in the production process of the release agent particles, and the surfactant is not mixed.

  Examples of the surfactant include the same ones as exemplified in the production of resin particles described later. In addition, examples of the anionic surfactant include polymer compounds having a carboxyl group salt in the side chain, such as sodium poly (meth) acrylate and sodium (meth) acrylate-sodium maleate copolymer.

The content of the surfactant in the dispersion of the release agent particles, that is, the addition amount of the surfactant is determined from the viewpoint of improving the releasability of the toner and widening the fixable temperature range. Preferably it is 0.5 mass part or less, More preferably, it is 0.1 mass part or less, More preferably, it is 0.05 mass part or less with respect to 100 mass parts in total of a) 0 mass part, ie, surfactant. More preferably, is not added.
In step (1), the ester wax (a1) and the release agent (a2) are preferably added to an aqueous medium and dispersed while heating at a temperature equal to or higher than the melting point of the release agent.
Specifically, the heating temperature at the time of dispersion is preferably at least the melting point of the release agent and at least 80 ° C., more preferably at least 85 ° C., even more preferably from the viewpoint of improving the productivity of the release agent particle dispersion. Is 90 ° C. or higher, preferably 100 ° C. or lower, more preferably 98 ° C. or lower, and still more preferably 95 ° C. or lower.
In addition, the heating time during dispersion is preferably 10 minutes or more, more preferably 15 minutes or more, still more preferably 20 minutes or more, and preferably 3 from the viewpoint of improving the productivity of the release agent particle dispersion. It is not more than time, more preferably not more than 2 hours, still more preferably not more than 1 hour.
The solid concentration of the dispersion of the release agent particles is preferably 5% by mass or more from the viewpoint of improving the dispersion stability of the release agent particles, from the viewpoint of easy handling, and from the viewpoint of improving the productivity of the toner. More preferably, it is 10 mass% or more, More preferably, it is 15 mass% or more, Preferably it is 40 mass% or more, More preferably, it is 30 mass% or more, More preferably, it is 25 mass% or more.
The volume median particle size (D ₅₀ ) of the release agent particles is preferably 0.05 μm or more from the viewpoint of obtaining uniform aggregated particles in the subsequent aggregation process and improving the durability of the obtained toner. Preferably it is 0.10 μm or more, more preferably 0.20 μm or more, still more preferably 0.25 μm or more, preferably 1 μm or less, more preferably 0.80 μm or less, still more preferably 0.60 μm or less, more More preferably, it is 0.50 micrometer or less, More preferably, it is 0.40 micrometer or less.
Here, the volume-median particle size (D ₅₀ ) is a particle size at which the cumulative volume frequency calculated by the volume fraction is 50% calculated from the smaller particle size, and is determined by the method described in the examples. Desired.
The coefficient of variation (CV value) (%) in the particle size distribution of the release agent particles is preferably 50% from the viewpoint of obtaining uniform aggregated particles in the subsequent aggregation step and improving the durability of the obtained toner. In the following, more preferably 40% or less, further preferably 35% or less, and from the viewpoint of improving the productivity of the release agent particle dispersion, it is preferably 15% or more, more preferably 20% or more, still more preferably. Is 25% or more. Here, the particle size distribution of the release agent particles is determined by the method described in the examples.

<Step (2)>
Step (2) is a step of obtaining aggregated particles by mixing the release agent particles, resin particles (A), and aggregating agent obtained in step (1) in an aqueous medium.
Step (2) may include the next step (2A), and may further include (2B) after step (2A).
Step (2A): Step (2B): Step of obtaining aggregated particles (1) by mixing the release agent particles, resin particles (A), and the flocculant obtained in step (1) in an aqueous medium. Aggregated particles (2) (resin particles) obtained by adding the resin particles (B) to the agglomerated particles (1) obtained in (2A) by adding the resin particles (B) at one time or divided into a plurality of times. (B) Step of Obtaining Adhesive Aggregated Particles Next, each component used in step (2), step (2A) and step (2B) will be described.

[Resin particles (A)]
The resin particles (A) in the present invention preferably contain polyester from the viewpoint of improving the low-temperature fixability and durability of the toner.
From the same viewpoint, the content of the polyester in the resin constituting the resin particles (A) is preferably 50% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, further preferably, in the resin. Is 90% by mass or more, more preferably substantially 100% by mass, and still more preferably 100% by mass.
As the resin constituting the resin particles (A), in addition to polyester, known resins used for toner, for example, styrene-acrylic copolymer, epoxy, polycarbonate, polyurethane and the like can be used.

The raw material monomer of the polyester used in the present invention is not particularly limited, and an arbitrary alcohol component and an arbitrary carboxylic acid component are used.
Examples of the carboxylic acid component include dicarboxylic acids, trivalent or higher polyvalent carboxylic acids, acid anhydrides thereof, and alkyl esters having 1 to 3 carbon atoms. Among them, dicarboxylic acids are preferable.
Specific examples of the dicarboxylic acid include aromatic dicarboxylic acid and aliphatic dicarboxylic acid. Examples of the aromatic dicarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid and the like. Examples of the aliphatic dicarboxylic acid include sebacic acid, fumaric acid, maleic acid, adipic acid, succinic acid, cyclohexanedicarboxylic acid, an alkyl group having 1 to 20 carbon atoms, or an succinic group substituted with an alkenyl group having 2 to 20 carbon atoms. An acid etc. are mentioned. Specific examples of the succinic acid substituted with an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms include dodecyl succinic acid, dodecenyl succinic acid, octenyl succinic acid, and the like. Among these, at least one selected from terephthalic acid, fumaric acid, dodecenyl succinic acid and acid anhydrides thereof is preferable from the viewpoint of improving low-temperature fixability and durability of the toner.
Specific examples of the trivalent or higher polyvalent carboxylic acid include trimellitic acid, 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid, and the like. Among them, the viewpoint of improving the low-temperature fixability and durability of the toner. Therefore, trimellitic acid and its acid anhydride are preferable, and trimellitic acid anhydride is more preferable.
A carboxylic acid component may be used individually by 1 type, and may be used in combination of 2 or more type.

Examples of the alcohol component include aliphatic diols having 2 to 12 carbon atoms, aromatic diols, alicyclic diols, trivalent or higher polyhydric alcohols, or alkylene oxides having 2 to 4 carbon atoms ( Average addition mole number 1-16) and adducts.
Preferred examples of the alcohol component include 2 carbon atoms of bisphenol A such as polyoxypropylene-2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene-2,2-bis (4-hydroxyphenyl) propane. 3 or less alkylene oxide (average added mole number 1 to 16) adduct, alicyclic diol such as hydrogenated bisphenol A or alkylene oxides having 2 to 4 carbon atoms (average added mole number 1 to 16) ) Adduct, ethylene glycol, propylene glycol, neopentyl glycol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol and other aliphatic diols having 2 to 12 main chain carbon atoms or the like Alkylene oxide having 2 to 4 carbon atoms (average added mole number 1 16 or less) adducts, trihydric or higher polyhydric alcohols such as glycerin, pentaerythritol, trimethylolpropane, sorbitol, or their alkylene oxides having 2 to 4 carbon atoms (average addition mole number of 1 to 16) adducts, etc. Is mentioned. You may use the said alcohol component in combination of 2 or more type. Examples of the alcohol component include polyoxypropylene-2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene-2,2-bis (4-hydroxyphenyl) propane from the viewpoint of improving the durability of the toner. An alkylene oxide (average addition mole number 1 to 16) adduct of bisphenol A having 2 to 3 carbon atoms is preferred.

Polyester, for example, polycondenses the alcohol component and the carboxylic acid component at a temperature of 180 ° C. or higher and 250 ° C. or lower using an esterification catalyst, a polymerization inhibitor, or the like as necessary in an inert gas atmosphere. Can be manufactured.
As the esterification catalyst, an esterification catalyst such as a tin compound such as dibutyltin oxide or di (2-ethylhexanoic acid) tin or a titanium compound such as titanium diisopropylate bistriethanolamate can be used. The amount of the esterification catalyst used is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and preferably 1 with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. It is not more than part by mass, more preferably not more than 0.8 part by mass.
Examples of the polymerization inhibitor include tert-butylcatechol. The amount of the polymerization inhibitor used is preferably 0.001 parts by mass or more, more preferably 0.005 parts by mass or more, and preferably 0 with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. 0.5 parts by mass or less, more preferably 0.1 parts by mass or less.

  As the polyester in the resin particles (A), either crystalline polyester or amorphous polyester can be used, and both can be mixed and used. However, in the present invention, the temperature range in which toner can be fixed is widened. Therefore, it is preferable to contain an amorphous polyester. The content of the amorphous polyester in the polyester in the resin particles (A) is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and still more preferably substantially. It is 100 mass%, More preferably, it is 100 mass%.

Here, the crystallinity of the resin is defined by the ratio between the softening point and the maximum endothermic peak temperature measured by a differential scanning calorimeter (DSC), that is, (softening point (° C)) / (maximum endothermic peak temperature (° C)). Expressed by the crystallinity index. The crystalline resin has a crystallinity index of 0.6 or more and 1.4 or less, and the amorphous resin is a resin having a crystallinity index of more than 1.4 or less than 0.6. The crystallinity index can be appropriately determined according to the production conditions such as the type and ratio of the raw material monomers, the reaction temperature, the reaction time, and the cooling rate. The maximum endothermic peak temperature refers to the temperature of the peak on the highest temperature side among the observed endothermic peaks. The maximum peak temperature is the melting point if the difference from the softening point is within 20 ° C., and the peak due to the glass transition if the difference from the softening point exceeds 20 ° C.
The softening point of the polyester is preferably 70 ° C. or higher, more preferably 90 ° C. or higher, and still more preferably 100 ° C. or higher, from the viewpoint of widening the fixable temperature range of the toner and improving the low-temperature fixability and durability. Also, it is preferably 165 ° C. or lower, more preferably 140 ° C. or lower, further preferably 130 ° C. or lower, and still more preferably 125 ° C. or lower.
The glass transition temperature of the polyester is preferably 50 ° C. or higher, more preferably 53 ° C. or higher, and further preferably 55 ° C. or higher, from the viewpoint of widening the fixable temperature range of the toner and improving low-temperature fixability and durability. In addition, it is preferably 85 ° C. or lower, more preferably 80 ° C. or lower, and further preferably 70 ° C. or lower.
The acid value of the polyester is preferably 6 mgKOH / g or more, more preferably 10 mgKOH / g, from the viewpoint of improving the dispersion stability of the resin particle dispersion, from the viewpoint of widening the fixable temperature range of the toner, and from the viewpoint of improving the durability. g or more, more preferably 15 mgKOH / g or more, preferably 35 mgKOH / g or less, more preferably 30 mgKOH / g or less, still more preferably 28 mgKOH / g or less.
The desired softening point, glass transition temperature, and acid value can be obtained by adjusting the type of alcohol component and carboxylic acid component, the charging ratio, the polycondensation temperature, and the reaction time.

  In the present invention, the polyester includes not only unmodified polyester but also polyester modified to such an extent that the properties are not substantially impaired. Examples of the modified polyester include grafting and blocking with phenol, urethane, epoxy and the like by the methods described in JP-A-11-133668, JP-A-10-239903, JP-A-8-20636, and the like. And a composite resin having two or more kinds of resin units including a polyester unit.

Further, when the resin particles contain a plurality of resins, the softening point, glass transition temperature, and acid value of the resin constituting the resin particles are the softening point, glass transition temperature, acid value as a mixture of each resin. Each value is preferably within a range of values of each characteristic of the polyester. The softening point, glass transition temperature, and acid value as a mixture can be determined by the weighted average of each value, that is, the sum of the product of the characteristic value and the content ratio of each resin.
Further, in the case of containing polyester, the resin constituting the resin particles (A) can contain two kinds of polyesters having different softening points, and can improve the low-temperature fixability and durability of the toner. From the viewpoint of widening the range, the softening point of one polyester (I) is preferably 70 ° C. or higher and lower than 115 ° C., and the softening point of the other polyester (II) is preferably 115 ° C. or higher and 165 ° C. or lower. Further, the difference in softening point between the two types of polyester resins is preferably 5 ° C. or higher, more preferably 10 ° C. or higher, and preferably 30 ° C. or lower, more preferably 20 ° C. or lower, from the same viewpoint. . The mass ratio (I / II) between the polyester (I) and the polyester (II) is 10/90 to 90/10 from the viewpoint of improving the low-temperature fixability and durability of the toner and widening the fixable temperature range. Is preferable, and 10/90 to 50/50 is more preferable.

  The resin particles (A) may contain a colorant, a release agent, and a charge control agent as long as the effects of the present invention are not impaired. Moreover, you may contain additives, such as reinforcement fillers, such as a fibrous material, antioxidant, and anti-aging agent, as needed.

(Coloring agent)
The resin particles (A) may be particles composed only of a resin or may be colorant-containing resin particles containing a colorant, but are colored from the viewpoint of obtaining uniform aggregated particles in a subsequent aggregation step. It is preferable that a colorant-containing resin particle containing a colorant is preferable.
When the resin particles (A) are colorant-containing resin particles, the content of the colorant is the resin 100 constituting the resin particles (A) from the viewpoint of improving the toner image density and improving the low-temperature fixability. Preferably it is 1 mass part or more with respect to a mass part, More preferably, it is 5 mass parts or more, Preferably it is 20 mass parts or less, More preferably, it is 10 mass parts or less.
As the colorant, pigments and dyes are used, and pigments are preferable from the viewpoint of improving the image density of the toner.
Specific examples of the pigment include carbon black, inorganic composite oxide, benzidine yellow, brilliantamine 3B, brilliantamine 6B, bengal, aniline blue, ultramarine blue, copper phthalocyanine, and phthalocyanine green. Among these, copper Phthalocyanine is preferred.
Specific examples of the dye include acridine series, azo series, benzoquinone series, azine series, anthraquinone series, indigo series, phthalocyanine series, and aniline black series.
A coloring agent can be used individually by 1 type or in combination of 2 or more types.

[Production of resin particles (A)]
The resin particles (A) can be produced by a method in which the above-mentioned optional components such as a polyester-containing resin, a surfactant, and a colorant are mixed in an aqueous medium to obtain a dispersion of the resin particles (A). preferable.
As the aqueous medium, those used when obtaining the release agent particles in the step (1) are preferably used.

In the present invention, when the resin particles (A) are produced as a dispersion, it is preferable to use a surfactant from the viewpoint of improving the dispersion stability of the resin particle dispersion.
Examples of the surfactant include nonionic surfactants, anionic surfactants, and cationic surfactants. Among them, nonionic surfactants are preferable, and nonionic surfactants and anionic surfactants are preferred. It is more preferable to use an active agent or a cationic surfactant in combination, and from the viewpoint of improving the dispersion stability of the resin particle dispersion, it is further preferable to use a nonionic surfactant and an anionic surfactant in combination. preferable.
When a nonionic surfactant and an anionic surfactant are used in combination, the mass ratio of the nonionic surfactant to the anionic surfactant (nonionic surfactant / anionic surfactant) is: From the viewpoint of improving the dispersion stability of the resin particle dispersion, it is preferably 0.3 or more, more preferably 0.5 or more, preferably 10 or less, more preferably 5 or less, and still more preferably 2 or less. is there.

Examples of nonionic surfactants include polyoxyethylene alkyl or alkenyl ethers, polyoxyethylene alkyl aryl ethers, polyoxyethylene fatty acid esters, oxyethylene / oxypropylene block copolymers, and the like.
Examples of the polyoxyethylene alkyl or alkenyl ether include polyoxyethylene oleyl ether and polyoxyethylene lauryl ether.
Examples of the polyoxyethylene alkyl aryl ether include polyoxyethylene nonyl phenyl ether.
Examples of the polyoxyethylene fatty acid ester include polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol monooleate and the like.
The nonionic surfactant is preferably polyoxyethylene alkyl or alkenyl ether, more preferably polyoxyethylene oleyl ether, from the viewpoint of improving the dispersion stability of the resin particle dispersion.
Examples of the anionic surfactant include alkylbenzene sulfonate, alkyl sulfate, alkyl ether sulfate, etc. From the viewpoint of improving the dispersion stability of the resin particle dispersion, alkylbenzene sulfonate, alkyl ether sulfate. Salts are preferred.
As the alkylbenzene sulfonate, an alkali metal salt of alkylbenzene sulfonic acid is preferable, and sodium alkylbenzene sulfonate is more preferable. The alkyl group is preferably a dodecyl group. As the alkyl benzene sulfonate, dodecyl benzene sulfonate is preferable, an alkali metal salt of dodecyl benzene sulfonic acid is more preferable, and sodium dodecyl benzene sulfonate is more preferable.
As the alkyl sulfate, an alkali metal salt of alkyl sulfate is preferable, and sodium alkyl sulfate is more preferable. The alkyl group is preferably a dodecyl group. As the alkyl sulfate, an alkali metal salt of dodecyl sulfate is more preferable, and sodium dodecyl sulfate is more preferable.
As the alkyl ether sulfate, an alkali metal salt of alkyl ether sulfate is preferable, and sodium alkyl ether sulfate is more preferable. The alkyl group is preferably a dodecyl group. The alkyl ether sulfate is preferably dodecyl ether sulfate, more preferably an alkali metal salt of dodecyl ether sulfate, and still more preferably sodium dodecyl ether sulfate.
As an example of the cationic surfactant, a quaternary ammonium salt is preferable, and examples thereof include alkylbenzyldimethylammonium chloride and alkyltrimethylammonium chloride.

  The amount of the surfactant used is preferably 0.1 parts by mass or more, more preferably from the viewpoint of improving the dispersion stability of the resin particle dispersion with respect to 100 parts by mass of the resin constituting the resin particles (A). 0.5 parts by mass or more, more preferably 1 part by mass or more. Further, from the viewpoint of improving the storage stability of the toner, it is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, still more preferably 10 parts by mass or less, and still more preferably 5 parts by mass or less.

  As a method of obtaining a dispersion containing the resin particles (A), a method in which a resin or the like is added to an aqueous medium and dispersed using a disperser, a phase inversion emulsification in which an aqueous medium is gradually added to the resin or the like and emulsified In view of widening the fixable temperature range of the obtained toner, the phase inversion emulsification method is preferable. Hereinafter, the phase inversion emulsification method will be described.

First, the above-mentioned optional components such as a polyester-containing resin, a surfactant, and a colorant are melted and mixed to obtain a resin mixture.
When the resin containing polyester is composed of a plurality of resins, a mixture of a plurality of resins may be used in advance, but when other components are added, they are added simultaneously and mixed by melting. May be obtained.
As a method for obtaining a resin mixture, the resin containing polyester, the surfactant, a coloring agent, and other optional components and an aqueous alkali solution are put in a container, and the resin is melted and mixed uniformly while stirring with a stirrer. The method is preferred.
Examples of the alkali in the alkaline aqueous solution include hydroxides of alkali metals such as potassium hydroxide and sodium hydroxide, ammonia and the like. From the viewpoint of improving the emulsion stability of the resin, potassium hydroxide and sodium hydroxide. Is preferred. The concentration of alkali in the aqueous alkali solution is preferably 1% by mass or more, more preferably 2% by mass or more, still more preferably 3% by mass or more, and preferably 10% by mass or less, more preferably 8% by mass. It is 7 mass% or less, More preferably, it is 7 mass% or less.

  The temperature at which the resin is melted and mixed is preferably equal to or higher than the glass transition temperature of the resin from the viewpoint of obtaining uniform resin particles, and more preferably equal to or higher than the melting point when crystalline polyester is included.

  Next, an aqueous medium is added to the resin mixture and phase inversion is performed to obtain a dispersion containing resin particles (A).

  From the viewpoint of obtaining homogeneous resin particles, the temperature at which the aqueous medium is added is preferably not less than the glass transition temperature of the resin, more preferably not less than 10 ° C. higher than the glass transition temperature, and includes a crystalline polyester. The melting point or higher is more preferable, and the melting point is preferably equal to or lower than the softening point of the resin, and more preferably equal to or lower than 5 ° C. below the softening point.

From the viewpoint of obtaining resin particles having a small particle diameter, the addition rate of the aqueous medium is preferably 0.1 parts by mass / 100 parts by mass of the resin constituting the resin particles (A) until the phase inversion is completed. Min. Or more, more preferably 0.5 mass parts / min or more, preferably 50 mass parts / min or less, more preferably 30 mass parts / min or less, still more preferably 10 mass parts / min or less, and even more. Preferably it is 5 mass parts / min or less. There is no restriction | limiting in the addition speed | rate of the aqueous medium after the resin phase is obtained after phase inversion.
The amount of the aqueous medium used is preferably 100 parts by mass or more, more preferably 150 parts by mass with respect to 100 parts by mass of the resin constituting the resin particles (A) from the viewpoint of obtaining uniform aggregated particles in the subsequent aggregation process. As mentioned above, More preferably, it is 170 mass parts or more, Preferably it is 900 mass parts or less, More preferably, it is 500 mass parts or less, More preferably, it is 300 mass parts or less.

From the viewpoint of improving the low-temperature fixability and durability of the toner, it is preferable to crosslink the polyester constituting the resin particles (A), and it is more preferable to crosslink with a compound having an oxazoline group.
The compound having an oxazoline group preferably contains a plurality of oxazoline groups in the molecule, and more preferably a polymer containing an oxazoline group. The weight average molecular weight of the polymer containing an oxazoline group is preferably 500 or more, more preferably 1,000 or more, and preferably 2,000,000 or less, more preferably, from the viewpoint of increasing the reactivity with the polyester. Is 1,000,000 or less.
Examples of commercially available polymers containing oxazoline groups include “Epocross WS Series” (water-soluble type, main chain acrylic), “K Series” (emulsion type, main chain styrene / acrylic) manufactured by Nippon Shokubai Co., Ltd. (All are trade names).
The content or addition amount of the compound having an oxazoline group is preferably as a solid content with respect to 100 parts by mass of the resin in the resin particle dispersion from the viewpoint of improving the crosslinking reactivity with the resin and improving the productivity. 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, further preferably 1 part by mass or more, and preferably 30 parts by mass or less, more preferably 20 parts by mass or less, still more preferably 10 parts by mass. It is as follows.

By adding and mixing a compound having an oxazoline group, the polyester contained in the resin particles (A) dispersed in the resin dispersion is crosslinked. The temperature during the crosslinking reaction is preferably 60 ° C. or higher, more preferably 70 ° C. or higher, and preferably 100 ° C. or lower, more preferably 98 ° C. or lower. The presence of the crosslinking can be confirmed by analyzing the presence of the amide group by a technique such as infrared absorption spectrum analysis.
The solid content concentration of the obtained dispersion of resin particles (A) is preferably 10 from the viewpoint of improving the dispersion stability of the resin particle dispersion, facilitating handling, and improving the productivity of the toner. It is at least 15% by mass, more preferably at least 15% by mass, even more preferably at least 20% by mass, preferably at most 50% by mass, more preferably at most 40% by mass, still more preferably at most 35% by mass. The solid content includes nonvolatile components such as resins, pigments, and surfactants.

The volume median particle size (D ₅₀ ) of the resin particles (A) in the dispersion of the resin particles (A) is preferably 0.02 μm or more, more preferably from the viewpoint of obtaining a toner capable of obtaining a high-quality image. 0.05 μm or more, more preferably 0.1 μm or more, preferably 2.0 μm or less, more preferably 1.5 μm or less, still more preferably 1.0 μm or less, even more preferably 0.5 μm or less, more More preferably, it is 0.3 μm or less.
Further, the coefficient of variation (CV value) (%) of the particle size distribution of the resin particles (A) is preferably 40% or less, more preferably 35% or less, from the viewpoint of obtaining a toner capable of obtaining a high-quality image. Preferably, it is 30% or less, and from the viewpoint of improving the productivity of the resin particle (A) dispersion, it is preferably 5% or more, more preferably 10% or more, and even more preferably 15% or more. In addition, CV value is a value represented by the following formula, and is calculated | required by the method as described in an Example.
CV value (%) = [standard deviation of particle size distribution (μm) / volume median particle size (μm)] × 100

[Step (2A)]
In the step (2A), the aforementioned release agent particles, resin particles (A), and aggregating agent are mixed in an aqueous medium to obtain agglomerated particles (1). At this time, a dispersion liquid of the above-mentioned release agent particles, a dispersion liquid of the resin particles (A), an aggregating agent and, if necessary, an aqueous medium are further added and mixed to obtain a dispersion liquid of the aggregated particles (1). Is preferred.
[Production of Aggregated Particles (1)]
Aggregated particles (1) are produced by a method in which optional components such as resin particles (A), release agent particles, aggregating agents, and colorants are mixed in an aqueous medium to obtain aggregated particles (1). Here, when mixing the said component, it is preferable to make it aggregate and obtain as a dispersion liquid of aggregated particle (1).

First, the resin particles (A) and release agent particles are mixed in an aqueous medium to obtain a mixed dispersion.
In addition, when a colorant is not mixed in the resin particles (A), it is preferable to mix a colorant in the mixed dispersion.
Further, resin particles other than the resin particles (A) may be mixed in the mixed dispersion. As resin particles other than resin particles (A), resin particles containing amorphous polyester are preferable, and those having the same composition as resin particles (B) described later are more preferable.
There is no restriction | limiting in order of mixing, You may add any in order and may add simultaneously.

The content of the resin particles (A) in 100 parts by mass of the mixed dispersion containing the resin particles (A) and the release agent particles is preferably 10 parts by mass or more from the viewpoint of improving the low-temperature fixability and productivity of the toner. More preferably, it is 15 parts by mass or more, preferably 40 parts by mass or less, more preferably 30 parts by mass or less.
Further, in 100 parts by mass of the mixed dispersion liquid containing the resin particles (A) and the release agent particles, the content of the aqueous medium is agglomerated particles having a target particle size by controlling the aggregation and the viewpoint of improving the productivity of the toner. From the viewpoint of obtaining, it is preferably 50 parts by mass or more, more preferably 60 parts by mass or more, and preferably 85 parts by mass or less, more preferably 80 parts by mass or less.
Further, the content of the colorant is preferably 2 parts by mass or more with respect to 100 parts by mass of the resin constituting the resin particles (A) from the viewpoint of improving the image density of the toner and improving the low-temperature fixability. More preferably, it is 3 mass parts or more, Preferably it is 20 mass parts or less, More preferably, it is 10 mass parts or less.
The content of the release agent particles is preferably 2 parts by mass or more, more preferably 3 parts by mass or more with respect to 100 parts by mass of the resin particles (A) from the viewpoint of improving the releasability and chargeability of the toner. Yes, and preferably 20 parts by mass or less, more preferably 15 parts by mass or less.
The mixing temperature is preferably 0 ° C. or higher and 40 ° C. or lower from the viewpoint of controlling aggregation and obtaining aggregated particles having a target particle size.

Next, the particles in the mixed dispersion can be aggregated to suitably obtain a dispersion of aggregated particles (1). It is preferable to add a flocculant for efficient aggregation.
Specific examples of the flocculant include quaternary salt cationic surfactants, organic flocculants such as polyethyleneimine; inorganic flocculants such as inorganic metal salts, inorganic ammonium salts, and bivalent metal complexes. It is done.
Examples of inorganic metal salts include metal salts such as sodium sulfate, sodium chloride, calcium chloride, magnesium sulfate, calcium nitrate, magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate, and inorganic metals such as polyaluminum chloride and polyaluminum hydroxide. A salt polymer is mentioned. Examples of inorganic ammonium salts include ammonium sulfate, ammonium chloride, and ammonium nitrate.
The flocculant is preferably an electrolyte, and more preferably a salt, from the viewpoint of obtaining a toner having a desired particle size while preventing excessive aggregation. The valence is preferably 1 to 5, more preferably 1 to 2, and even more preferably 1. That is, it is preferable to use a monovalent salt. Here, the monovalent salt means that the valence of the metal ion or cation constituting the salt is 1. Examples of the monovalent salt include the inorganic metal salts, inorganic ammonium salts, and the like, and inorganic ammonium salts are preferable.
The flocculant is preferably an inorganic ammonium salt and more preferably ammonium sulfate from the viewpoint of improving the flocculence and obtaining uniform agglomerated particles.

  From the viewpoint of improving the durability of the toner, the use amount of the flocculant is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and more preferably 35 parts by mass with respect to 100 parts by mass of the resin constituting the resin particles (A). Part or less is more preferable. Further, from the viewpoint of controlling the aggregation of the resin particles to obtain a target particle size, it is preferably 1 part by mass or more, more preferably 10 parts by mass or more, with respect to 100 parts by mass of the resin constituting the resin particles (A). More preferred is part by mass.

As an aggregating method, an aggregating agent is preferably dropped into an aqueous medium solution into a container containing a mixed dispersion. The flocculant may be added at once, or may be added continuously or intermittently. Moreover, it can also be divided and added. It is preferable to sufficiently stir at the time of adding the flocculant and after completion of the addition. From the viewpoint of controlling aggregation and obtaining aggregated particles having a desired particle diameter and improving the productivity of the toner, the dropping time of the aggregating agent is preferably from 1 minute to 120 minutes. The dropping temperature is preferably 0 ° C. or higher and 50 ° C. or lower from the viewpoint of controlling aggregation and obtaining aggregated particles having a target particle size.
Further, from the viewpoint of promoting aggregation, controlling the particle size of the aggregated particles, and suppressing the formation of coarse particles, it is preferable to increase the temperature of the dispersion after adding the coagulant. From the viewpoint of controlling the agglomerated particles to a small and sharp particle size distribution, the temperature in the agglomerated system is set to a temperature not more than 25 ° C. higher than the glass transition temperature of the resin constituting the resin particles (A) From the viewpoint of suppressing the formation of coarse particles, it is more preferably a temperature that is 30 ° C. lower than the glass transition temperature and 25 ° C. lower than the glass transition temperature. It is preferable to confirm the progress of aggregation by monitoring the volume-median particle size of the aggregated particles in the temperature range. The volume median particle size is measured by the method described in the examples.

  The volume-median particle size of the obtained aggregated particles (1) is preferably 10 μm or less, more preferably 8 μm or less, and even more preferably 6 μm, from the viewpoint of obtaining a toner capable of obtaining a high-quality image and suppressing toner scattering. In addition, it is preferably 1 μm or more, more preferably 2 μm or more, and further preferably 3 μm or more. The coefficient of variation (CV value) in the particle size distribution is preferably 30% or less, more preferably 28% or less, and even more preferably 25% or less, from the viewpoint of obtaining a toner capable of obtaining a high-quality image. Further, from the viewpoint of improving toner productivity, it is preferably 5% or more, more preferably 10% or more, and further preferably 15% or more. The volume-median particle size and CV value of the aggregated particles (1) are specifically determined by the method described in the examples.

[Step (2B)]
Step (2B) is an aggregate formed by adding resin particles (B) to aggregated particles (1) obtained in step (2A) by adding resin particles (B) at a time or divided into multiple times. This is a step of obtaining particles (2) (resin particles (B) adhered aggregated particles). At this time, the resin particles (B) are adhered to the dispersion liquid of the aggregated particles (1) described in the step (2A) by adding the resin particles (B) at one time or divided into a plurality of times, thereby attaching the resin particles (B). It is preferable to obtain a dispersion of (2) (resin particles (B) adhered and agglomerated particles).
By performing this step (2B), it is possible to better prevent the release agent or the like from flowing out of the toner particles.

When the resin particles (B) are added in multiple portions, the amount of each resin particle (B) is preferably the same amount. In addition, when the resin particles (B) are added in a plurality of divided portions, the number of times is not particularly limited, but is preferably twice or more from the viewpoint of controlling the particle size of the formed aggregated particles (2). Moreover, from the viewpoint of improving the productivity of the aggregated particles (2), it is preferably 10 times or less, more preferably 8 times or less.
[Resin particles (B)]
In the present invention, the resin particles (B) added to the aggregated particles (1) are not particularly limited, and for example, those prepared in the same manner as the resin particles (A) in the present invention can be used. In the present invention, the resin particles (B) preferably contain polyester from the viewpoint of improving the low-temperature fixability and durability of the toner. The polyester content is preferably 50% by mass or more, more preferably 80% by mass or more, and still more preferably 90% in the resin constituting the resin particles (B) from the viewpoint of improving low-temperature fixability and durability of the toner. % By mass or more, still more preferably 100% by mass, still more preferably 100% by mass.
As the polyester, a polyester similar to the polyester used for the resin particles (A) can be preferably used. A resin made of the same raw material monomer as the polyester used for the resin particles (A) may be used, or a resin made of a different raw material monomer may be used.

  Moreover, the polyester used for the resin particles (B) can be produced by a polycondensation reaction between an acid component and an alcohol component in the same manner as the polyester used for the resin particles (A). Specific examples of preferable acid component and alcohol component are the same as those of the polyester used in the resin particles (A).

The glass transition temperature, softening point, and acid value of the polyester used for the resin particles (B) are preferably in the same range as the polyester used for the resin particles (A).
Moreover, the polyester used for the resin particles (B) can contain two types of polyesters having different softening points, and the preferred embodiment is the same as the polyester used for the resin particles (A).
In the present invention, the resin particles (B) may be the same as or different from the resin particles (A) in the present invention, but the viewpoint of improving the low-temperature fixability and durability of the toner. Therefore, the resin particles (A) in the present invention are preferably resin particles (B) having different glass transition temperatures, softening points, and the like.
The resin particles (B) are preferably produced by a method in which the above-mentioned optional components such as a polyester-containing resin and a colorant are dispersed in an aqueous medium to obtain a dispersion containing the resin particles (B).
A preferred embodiment of a method for obtaining a dispersion containing resin particles (B) is the same as the method for obtaining a dispersion containing resin particles (A). However, it is not necessary to crosslink the polyester resin.
The solid content concentration of the dispersion of the resin particles (B) is preferably 10% by mass from the viewpoint of improving the dispersion stability of the resin particle dispersion, facilitating handling, and improving the productivity of the toner. As mentioned above, More preferably, it is 15 mass% or more, More preferably, it is 20 mass% or more. Further, it is preferably 50% by mass or less, more preferably 40% by mass or less, and still more preferably 35% by mass or less. In addition, solid content is the total amount of non-volatile components, such as resin and surfactant.

The volume median particle size of the resin particles (B) in the dispersion of the resin particles (B) is preferably 0.02 μm or more, more preferably 0.05 μm or more, from the viewpoint of obtaining a toner capable of obtaining a high-quality image. More preferably, it is 0.1 μm or more, preferably 1.5 μm or less, more preferably 1 μm or less, still more preferably 0.5 μm or less, and still more preferably 0.3 μm or less.
Further, the coefficient of variation (CV value) (%) of the particle size distribution of the resin particles (B) is preferably 40% or less, more preferably 35% or less from the viewpoint of obtaining a toner capable of obtaining a high-quality image. Preferably, it is 30% or less. Further, from the viewpoint of improving the productivity of the resin particle (B) dispersion, it is preferably 5% or more, more preferably 10% or more, and further preferably 15% or more.
Further, the resin particles (B) may be particles composed only of a resin, but from the viewpoint of improving the image density of the obtained toner and improving the low-temperature fixability, similarly to the resin particles (A), It is preferable to contain a colorant, and colorant-containing resin particles containing a colorant are preferable. It is more preferable that the resin particles (A) and (B) are both colorant-containing resin particles.
When the resin particles (B) are colorant-containing resin particles, the content of the colorant is based on 100 parts by mass of the resin constituting the resin particles (B) from the viewpoint of improving the image density and low-temperature fixability of the toner. The amount is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and preferably 20 parts by mass or less, more preferably 10 parts by mass or less.
The timing for adding the resin particles (B) is not particularly limited as long as the resin particles (B) can be attached to the aggregated particles (1). From the viewpoint of controlling the particle size of the aggregated particles (2), however, It is preferable that the process is up to the fusion process.
When the resin particle (B) dispersion is added to the aggregated particle (1) dispersion, the aggregating agent may be used in this step in order to efficiently attach the resin particle (B) to the aggregated particle (1). Good.

  The temperature in the system in this step is 5 ° C. or more lower than the melting point when crystalline polyester is contained in the resin constituting the resin particles (A) from the viewpoint of improving low-temperature fixability and durability of the toner. A temperature not higher than 3 ° C. is higher than the glass transition temperature of the resin constituting the resin particles (B). When the aggregated particles (2) are produced in this temperature range, the low-temperature fixability and durability of the obtained toner are improved. Although the reason is not certain, it is considered that the generation of coarse particles is suppressed because fusion of the aggregated particles (2) does not occur.

The blending ratio (aggregated particles (1) / resin particles (B)) of the agglomerated particles (1) and the resin particles (B) in the dispersion of the agglomerated particles (2) is a viewpoint for improving the low-temperature fixability and durability of the toner. From a mass ratio, it is preferably 0.1 or more, more preferably 0.5 or more, still more preferably 1.0 or more, still more preferably 1.5 or more, still more preferably 2.0 or more, preferably Is 3.0 or less, more preferably 2.8 or less, and still more preferably 2.7 or less.
The volume median particle size (D ₅₀ ) of the agglomerated particles (2) is preferably 1 μm or more, more preferably 2 μm or more, still more preferably 3 μm or more, and even more preferably, from the viewpoint of obtaining a toner capable of obtaining a high-quality image. Is 4 μm or more, preferably 10 μm or less, more preferably 9 μm or less, still more preferably 8 μm or less, and still more preferably 6 μm or less.

Resin particles (B) are added, and aggregation is stopped when the toner particles grow to an appropriate particle size.
Methods for stopping the aggregation include a method of cooling the dispersion and a method of adding an aggregation terminator. From the viewpoint of reliably preventing unnecessary aggregation, the aggregation is stopped by adding an aggregation terminator. The method of making it preferable is.
As the aggregation terminator, a surfactant is preferably used, and an anionic surfactant is more preferably used. Examples of the anionic surfactant include alkyl ether sulfates, alkyl sulfates, linear alkylbenzene sulfonates, and polyoxyethylene alkyl ether sulfates. Polyoxyethylene alkyl ether sulfates are preferable, and polyoxyethylene lauryl is preferable. Sodium ether sulfate is more preferred.
The aggregation terminator may be used singly or in combination of two or more.

  From the viewpoint of stopping the aggregation, the addition amount of the aggregation terminator is the resin constituting the aggregated particles (1) or the resin constituting the aggregated particles (2) (that is, the resin and the resin particles constituting the aggregated particles (1)) (Total amount of resin constituting (B)) The amount is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, and further preferably 2 parts by mass or more with respect to 100 parts by mass. From the viewpoint of reducing the amount, it is preferably 10 parts by mass or less, more preferably 5 parts by mass or less. The aggregation terminator may be added in any form as long as it is added, but it is preferably added in an aqueous solution from the viewpoint of improving productivity.

<Step (3)>
Step (3) is a step of fusing the aggregated particles obtained in step (2) to obtain fused particles.
Here, the “aggregated particles obtained in the step (2)” means the aggregated particles (1) obtained in the step (2A) when the step (2B) is not performed, and the step (2B). In the case of carrying out the step, it means the aggregated particles (2) obtained in the step (2B).
The resin particles (B) adhered aggregated particles are the resin particles in the aggregated particles (1), the resin particles in the aggregated particles (2) (resin particles (B) adhered aggregated particles) at the time of fusion. And the release agent particles, the resin particles (B), and the aggregated particles (1) and the resin particles (B) in the aggregated particles (2) (resin particles (B) adhered aggregated particles) are mainly physical. The agglomerated particles (1) are united and united with each other, and the resin particles (B) and the agglomerated particles (1) and the resin particles (B) are fused. It is presumed that the particles are fused and become fused particles.

The heating temperature at the time of fusing is set to be not less than the glass transition temperature of the resin constituting the agglomerated particles (2) and not more than 100 ° C. from the viewpoints of improving the fusing property of the agglomerated particles and improving the productivity of the toner. The glass transition temperature of the resin constituting the agglomerated particles (2) is more preferable, and the glass transition temperature of the resin constituting the agglomerated particles (2) is more preferable. The temperature is higher than the temperature and lower than 85 ° C.
The holding time in this step is preferably 10 minutes or more, more preferably 30 minutes or more, and still more preferably from the viewpoint of improving the fusibility of the aggregated particles and improving the durability, chargeability and productivity of the toner. It is 1 hour or longer, preferably 24 hours or shorter, more preferably 10 hours or shorter, still more preferably 5 hours or shorter, still more preferably 3 hours or shorter.
From the viewpoint of obtaining a high-quality image, the volume-median particle size of the fused particles obtained in this step is preferably 2 μm or more, more preferably 3 μm or more, still more preferably 4 μm or more, and preferably 10 μm or less. More preferably, it is 8 micrometers or less, More preferably, it is 7 micrometers or less, More preferably, it is 6 micrometers or less.
In addition, it is preferable that the average particle diameter of the fusion | melting particle | grains obtained at this process is below the average particle diameter of aggregated particle (2). That is, in this step, it is preferable that the fused particles do not aggregate and fuse.

[Post-processing process]
In the present invention, a post-treatment step may be performed after step (3), and it is preferable to obtain toner particles by isolating the fused particles.
Since the fused particles obtained in the step (3) are present in the aqueous medium, it is preferable to first perform solid-liquid separation. For solid-liquid separation, a suction filtration method or the like is preferably used.
It is preferable to perform washing after the solid-liquid separation. When a nonionic surfactant is used in the production of the resin particles (A) and (B), it is preferable to remove the added nonionic surfactant, so the cloud point of the nonionic surfactant In the following, it is preferable to wash with an aqueous medium. The washing is preferably performed a plurality of times.
Next, although it is preferable to dry, the temperature at the time of drying is lower than the glass transition temperature of the resin constituting the fused particles by 5 ° C. or more, and includes crystalline polyester. The temperature is preferably set to be 5 ° C. or more lower than the melting point, and more preferably set to be 10 ° C. or more lower.
As a drying method, any method such as a vacuum low temperature drying method, a vibration type fluidized drying method, a spray drying method, a freeze drying method, a flash jet method, or the like can be adopted. The water content after drying of the toner particles is preferably adjusted to 1.5% by mass or less, more preferably 1.0% by mass or less, from the viewpoint of improving the chargeability of the toner.
From the viewpoint of obtaining a high-quality image, the volume median particle size of the toner particles or the toner described later is preferably 2 μm or more, more preferably 3 μm or more, further preferably 4 μm or more, and preferably 10 μm or less. Preferably it is 8 micrometers or less, More preferably, it is 7 micrometers or less, More preferably, it is 6 micrometers or less.
The CV value of toner particles or toner described later is preferably 30% or less, more preferably 28% or less, and even more preferably 27% or less, from the viewpoint of improving image quality. Further, from the viewpoint of improving toner productivity, it is preferably 5% or more, more preferably 10% or more, and further preferably 15% or more.
The volume median particle size (D ₅₀ ) and CV value of the toner particles are determined by the method described in the examples.

[Toner for electrostatic image development]
Toner particles obtained by drying or the like can be used as the toner of the present invention as they are, but it is preferable to use toner particles whose surface has been treated as described below as toner for developing electrostatic images.
The softening point of the toner for developing an electrostatic charge image of the present invention is preferably 60 ° C. or higher, preferably 140 ° C. or lower, more preferably 130 ° C. or lower, from the viewpoint of improving the low-temperature fixability and durability of the toner. More preferably, it is 120 ° C. or lower.

In the toner for developing an electrostatic charge image obtained by the production method of the present invention, the toner particles may be used as the toner as they are, but an additive such as a fluidizing agent is added to the surface of the toner particles as an external additive. It is preferable to use a toner. Examples of the external additive include silica fine particles whose surfaces are hydrophobized, titanium oxide fine particles, alumina fine particles, cerium oxide fine particles, inorganic fine particles such as carbon black, and polymer fine particles such as polycarbonate, polymethyl methacrylate, and silicone resin. Among these, hydrophobic silica is preferable.
The addition amount of the external additive is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and further preferably 3 parts by mass or more with respect to 100 parts by mass of the toner particles before the treatment with the external additive. , Preferably 5 parts by mass or less, more preferably 4.7 parts by mass or less.
The electrostatic image developing toner obtained by the present invention can be used as a one-component developer or mixed with a carrier and used as a two-component developer.

In this specification, in addition to the above, the following method for producing a toner for developing an electrostatic image is disclosed.
<1> A method for producing an electrostatic charge image developing toner comprising the following steps (1) to (3).
Step (1): A release agent (a) containing an ester wax (a1) having an acid value of 1 mgKOH / g to 10 mgKOH / g and a release agent (a2) other than the ester wax (a1), pH 9. 5 or more and 14 or less, preferably no surfactant is added, or the surfactant content is 0.5 parts by mass or less with respect to 100 parts by mass of the total amount of the release agent (a), preferably surface active Preparation of release agent particles by dispersing in an aqueous medium under conditions where no agent is added Step (2): Release agent particles, resin particles, and aggregating agent obtained in step (1) are added in an aqueous medium. Step (3) for obtaining aggregated particles by mixing in step: Step for obtaining fused particles by fusing the aggregated particles obtained in step (2)

<2> The method for producing a toner for developing an electrostatic charge image according to <1>, wherein the ester wax (a1) is at least one of a synthetic ester wax and a natural ester wax.
<3> The synthetic ester wax may be an ester composed of a long-chain alcohol and a fatty acid, and is preferably at least one fatty acid ester of behenyl behenate, stearyl stearate, and pentaerythritol, according to <2>. A method for producing a toner for developing a charge image.
<4> The method for producing a toner for developing an electrostatic charge image according to <2> or <3>, wherein the natural ester wax is at least one of carnauba wax and rice wax, preferably carnauba wax.
<5> The acid value of the ester wax (a1) is 1 mgKOH / g or more, preferably 2 mgKOH / g or more, more preferably 3 mgKOH / g or more, and 10 mgKOH / g or less, preferably 8 mgKOH. / G or less, more preferably 7 mgKOH / g or less, The method for producing a toner for developing an electrostatic charge image according to any one of <1> to <4>.

<6> The melting point of the ester wax (a1) is preferably 100 ° C. or less, more preferably 95 ° C. or less, still more preferably 90 ° C. or less, still more preferably 88 ° C. or less, and preferably 60 ° C. or more. The method for producing a toner for developing an electrostatic charge image according to any one of <1> to <5>, more preferably 65 ° C. or higher, further preferably 70 ° C. or higher, and still more preferably 75 ° C. or higher.
<7> The content of the ester wax (a1) is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, and still more preferably 8% by mass or more. The electrostatic charge image according to any one of <1> to <6>, preferably 49% by mass or less, more preferably 40% by mass or less, still more preferably 30% by mass or less, and still more preferably 20% by mass or less. A method for producing a developing toner.
<8> The release agent (a2) contains at least one of a hydrocarbon wax, a silicone wax, a fatty acid amide, and an ester wax having an acid value of less than 1 mgKOH / g or more than 10 mgKOH / g, preferably a hydrocarbon. The method for producing a toner for developing an electrostatic image according to any one of <1> to <7>, comprising a wax.
<9> The hydrocarbon wax includes at least one kind of low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene; mineral / petroleum waxes such as ozokerite, ceresin, paraffin wax, microcrystalline wax, and Fischer-Tropsch wax. The method for producing a toner for developing an electrostatic charge image according to <8>, preferably containing paraffin wax.

<10> The melting point of the release agent (a2) is preferably 100 ° C. or lower, more preferably 95 ° C. or lower, still more preferably 90 ° C. or lower, still more preferably 80 ° C. or lower, and preferably 60 ° C. As described above, the method for producing a toner for developing an electrostatic charge image according to any one of <1> to <9>, which is more preferably 63 ° C. or higher, and further preferably 65 ° C. or higher.
<11> Mass ratio of ester wax (a1) to mold release agent (a2) [ester wax (a1) / release agent (a2)] is preferably 1/99 to 49/51, more preferably 3 / 97 to 40/60, more preferably 5/95 to 30/70, and still more preferably 8/92 to 20/80, the electrostatic charge image developing toner according to any one of <1> to <10> Production method.
<12> The total content of the ester wax (a1) and the release agent (a2) in the release agent (a) is preferably 80% by mass or more, more preferably 90% by mass or more, and still more preferably 95% by mass. The toner for developing electrostatic images according to any one of <1> to <11>, more preferably 99% by mass or more, still more preferably substantially 100% by mass, and still more preferably 100% by mass. Manufacturing method.
<13> The amount of the release agent (a) used is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and further preferably 5 parts by mass or more with respect to 100 parts by mass of the resin in the toner. The method for producing a toner for developing an electrostatic charge image according to any one of <1> to <12>, which 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.
<14> In step (1), the pH is preferably 10 or more, more preferably 11 or more, still more preferably 11.5 or more, still more preferably 12 or more, and preferably 13.5 or less, more preferably The electrostatic charge image according to any one of <1> to <13>, wherein the release agent particles are prepared by dispersing the release agent (a) in an aqueous medium at 13 or less, more preferably 12.5 or less. A method for producing a developing toner.

<15> In step (1), the pH is adjusted to at least one of a basic compound, preferably a metal hydroxide and an amine, more preferably lithium hydroxide, sodium hydroxide, potassium hydroxide, ammonia, dimethylamine, The method for producing a toner for developing an electrostatic charge image according to any one of <1> to <14>, wherein the toner is prepared by using at least one of triethylamine and diethanolamine, more preferably sodium hydroxide and potassium hydroxide.
<16> In step (1), the heating temperature during dispersion is preferably not less than the melting point of the release agent and not less than 80 ° C., more preferably not less than 85 ° C., still more preferably not less than 90 ° C., and preferably 100 The heating time during dispersion is preferably 10 minutes or more, more preferably 15 minutes or more, and even more preferably 20 minutes or more. The method for producing a toner for developing an electrostatic charge image according to any one of <1> to <15>, preferably 3 hours or less, more preferably 2 hours or less, and still more preferably 1 hour or less.
<17> In the step (1), the solid content concentration of the dispersion of the release agent particles is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more. Is 40% by mass or more, more preferably 30% by mass or more, and still more preferably 25% by mass or more. The method for producing a toner for developing an electrostatic charge image according to any one of <1> to <16>.
<18> In the step (1), the volume median particle size (D ₅₀ ) of the release agent particles is preferably 0.05 μm or more, more preferably 0.10 μm or more, still more preferably 0.20 μm or more, and still more. Preferably, it is 0.25 μm or more, preferably 1 μm or less, more preferably 0.80 μm or less, still more preferably 0.60 μm or less, still more preferably 0.50 μm or less, even more preferably 0.40 μm or less. Further, the coefficient of variation (CV value) (%) of the particle size distribution of the release agent particles is preferably 50% or less, more preferably 40% or less, and further preferably 35% or less. From the viewpoint of improving the productivity of the agent particle dispersion, it is preferably 15% or more, more preferably 20% or more, and still more preferably 25% or more, according to any one of <1> to <17>. A method for producing a toner for developing a charge image.
<19> The method for producing a toner for developing an electrostatic charge image according to any one of <1> to <18>, wherein in the step (2), the resin particles contain polyester.

<20> The step (2) may include the next step (2A), and may further include (2B) after the step (2A), according to any one of <1> to <19>. A method for producing a toner for developing an electrostatic image.
Step (2A): Step (2B): Step of obtaining aggregated particles (1) by mixing the release agent particles, resin particles (A), and the flocculant obtained in step (1) in an aqueous medium. To the aggregated particles (1) obtained in (2A), the resin particles (B) are added at one time or divided into a plurality of times, and the aggregated particles (2) (resin ( B) Step of obtaining particle adhering aggregated particles) The content of the polyester in the resin constituting the <21> resin particles (A) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably in the resin. Is 80% by mass or more, more preferably 90% by mass or more, still more preferably substantially 100% by mass, and even more preferably 100% by mass. The method for producing a toner for developing an electrostatic charge image according to <20>.
The alcohol component which is a raw material monomer of <22> polyester is preferably polyoxypropylene-2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene-2,2-bis (4-hydroxyphenyl) propane or the like. The method for producing an electrostatic charge image developing toner according to <21>, which is an adduct of bisphenol A having 2 to 3 carbon atoms and an alkylene oxide (average addition mole number of 1 to 16).

<23> The polyester in the resin particles (A) is at least one of a crystalline polyester and an amorphous polyester, preferably contains an amorphous polyester, and the amorphous polyester in the polyester in the resin particles (A) The content of is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, still more preferably substantially 100% by mass, and still more preferably 100% by mass. <20>-<22> The manufacturing method of the electrostatic image developing toner in any one of.
The softening point of the polyester in <24> resin particles (A) is preferably 70 ° C or higher, more preferably 90 ° C or higher, still more preferably 100 ° C or higher, and preferably 165 ° C or lower, more preferably 140 ° C. The method for producing a toner for developing an electrostatic charge image according to any one of <20> to <23>, further preferably 130 ° C. or lower, and more preferably 125 ° C. or lower.
<25> The glass transition temperature of the polyester in the resin particles (A) is preferably 50 ° C. or higher, more preferably 53 ° C. or higher, still more preferably 55 ° C. or higher, and preferably 85 ° C. or lower, more preferably 80 ° C. The method for producing a toner for developing an electrostatic charge image according to any one of <20> to <24>, which is not higher than 70C, more preferably not higher than 70C.
The acid value of the polyester in <26> resin particles (A) is preferably 6 mgKOH / g or more, more preferably 10 mgKOH / g or more, still more preferably 15 mgKOH / g or more, and preferably 35 mgKOH / g or less. The method for producing a toner for developing an electrostatic charge image according to any one of <20> to <25>, preferably 30 mgKOH / g or less, more preferably 28 mgKOH / g or less.
<27> The resin constituting the resin particle (A) contains two kinds of polyesters having different softening points, and the softening point of one polyester (I) is preferably 70 ° C. or higher and lower than 115 ° C. The softening point of the polyester (II) is preferably 115 ° C. or higher and 165 ° C. or lower, and the difference between the softening points of the two polyester resins is preferably 5 ° C. or higher, more preferably 10 ° C. or higher. The mass ratio (I / II) of the polyester (I) to the polyester (II) is preferably 10/90 to 90/10, more preferably 10 The method for producing a toner for developing an electrostatic charge image according to any one of <20> to <26>, which is / 90 to 50/50.

<28> Step (2A) includes a step of mixing the resin particles (A) and the release agent particles in an aqueous medium to obtain a mixed dispersion, and the resin particles (A) in 100 parts by mass of the mixed dispersion Is preferably 10 parts by mass or more, more preferably 15 parts by mass or more, preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and in 100 parts by mass of the mixed dispersion. The content of the aqueous medium is preferably 50 parts by mass or more, more preferably 60 parts by mass or more, and preferably 85 parts by mass or less, more preferably 80 parts by mass or less. The amount is preferably 2 parts by mass or more, more preferably 3 parts by mass or more, and preferably 20 parts by mass or less, more preferably 10 parts by mass with respect to 100 parts by mass of the resin constituting the resin particles (A). Less than or equal to The content of the release agent particles is preferably 2 parts by mass or more, more preferably 3 parts by mass or more, and preferably 20 parts by mass or less, based on 100 parts by mass of the resin particles (A). The method for producing a toner for developing an electrostatic charge image according to any one of <20> to <27>, preferably 15 parts by mass or less.
<29> In the step (2B), the resin particles (B) are added to the dispersion of the aggregated particles (1) at a time or a plurality of times, preferably 2 times or more, preferably 10 times or less, more preferably 8 times. Any one of <20> to <28>, which is added in divided portions to obtain a dispersion of aggregated particles (2) (resin particles (B) adhered aggregated particles) formed by adhering resin particles (B). A method for producing a toner for developing an electrostatic image as described in 1.
<30> The resin particles (B) contain polyester prepared in the same manner as the resin particles (A), and the content of the polyester is preferably 50% by mass or more in the resin constituting the resin particles (B). More preferably 80% by mass or more, still more preferably 90% by mass or more, still more preferably substantially 100% by mass, and still more preferably 100% by mass, <20> to <29> A method for producing the toner for developing an electrostatic image according to claim 1.
The blending ratio of <31> aggregated particles (1) and resin particles (B) (aggregated particles (1) / resin particles (B)) is preferably a mass ratio, preferably 0.1 or more, more preferably 0.5 or more. More preferably, it is 1.0 or more, more preferably 1.5 or more, still more preferably 2.0 or more, preferably 3.0 or less, more preferably 2.8 or less, still more preferably 2.7. The method for producing a toner for developing an electrostatic image according to any one of <20> to <30>, wherein:

In <32> step (3), the heating temperature at the time of fusing is a temperature that is not lower than the glass transition temperature of the resin constituting the aggregated particles (2) and not higher than 100 ° C., preferably the aggregated particles (2). <1> to a temperature such that the glass transition temperature is not lower than 90 ° C. and more preferably not higher than the glass transition temperature of the resin constituting the aggregated particles (2) and not higher than 85 ° C. <31> The method for producing a toner for developing an electrostatic charge image according to any one of the above.
The volume median particle size of <33> toner particles or toner described later is preferably 2 μm or more, more preferably 3 μm or more, further preferably 4 μm or more, and preferably 10 μm or less, more preferably 8 μm or less, and further The method for producing a toner for developing an electrostatic charge image according to any one of <1> to <32>, which is preferably 7 μm or less, and more preferably 6 μm or less.
<34> The CV value of the toner particles or the toner described later is preferably 30% or less, more preferably 28% or less, still more preferably 27% or less, and preferably 5% or more, more preferably 10% or more. The method for producing a toner for developing an electrostatic charge image according to any one of <1> to <33>, more preferably 15% or more.
<35> The softening point of the toner particles or toner is preferably 60 ° C. or higher, preferably 140 ° C. or lower, more preferably 130 ° C. or lower, and further preferably 120 ° C. or lower. <1> to <34 The method for producing a toner for developing an electrostatic charge image according to any one of the above.

Each property value of polyester, resin particles, toner, etc. was measured and evaluated by the following method.
[Acid value of resin]
It measured according to JIS K0070. However, the measurement solvent was a mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

[Softening point of resin and toner]
Using a flow tester “CFT-500D” (manufactured by Shimadzu Corporation), a 1 g sample was heated at a heating rate of 6 ° C./min, and a load of 1.96 MPa was applied by a plunger, and the diameter was 1 mm and the length was 1 mm. Extruded from the nozzle. The amount of plunger drop of the flow tester was plotted against the temperature, and the temperature at which half of the sample flowed out was taken as the softening point.

[Glass transition temperature and crystallinity index of resin]
(1) Maximum endothermic peak temperature and glass transition temperature Using a differential scanning calorimeter “Pyris 6 DSC” (manufactured by PerkinElmer), the temperature is raised to 200 ° C., and the temperature is lowered to 0 ° C. at a temperature lowering rate of 10 ° C./min. The measured samples were measured at a heating rate of 10 ° C./min. Among the observed peaks, the peak temperature with the maximum peak area is defined as the maximum peak temperature of the endotherm, and the base line extension below the maximum peak temperature of the endotherm and the maximum slope from the peak of the peak to the peak apex. The intersection temperature with the tangent line was defined as the glass transition temperature.

(2) Crystallinity index The softening point of the resin and the ratio of the softening point obtained by (1) to the maximum endothermic peak temperature (softening point / maximum endothermic peak temperature) were calculated as the crystallinity index.

[Melting point of release agent]
Using a differential scanning calorimeter “DSC210” (manufactured by Seiko Denshi Kogyo Co., Ltd.), the temperature was measured from 20 ° C. at a heating rate of 10 ° C./min, and the maximum peak temperature was taken as the melting point.

[Volume Median Particle Size (D ₅₀ ) and CV Value of Resin Particle (A), Resin Particle (B), and Release Agent Particle]
(1) Measuring apparatus: Laser diffraction particle size measuring instrument “LA-920” (manufactured by Horiba, Ltd.)
(2) Measurement conditions: Distilled water was added to the measurement cell, and the volume-median particle size (D ₅₀ ) was measured at a temperature at which the absorbance falls within an appropriate range. The CV value (particle size distribution) was calculated according to the following formula.
CV value (%) = (standard deviation of particle size distribution / volume median particle size (D ₅₀ )) × 100

[Solid Concentration of Resin Particle (A), Resin Particle (B), and Release Agent Particle Dispersion]
Using an infrared moisture meter “FD-230” (manufactured by Kett Science Laboratory Co., Ltd.), a measurement sample 5 g was dried at a temperature of 150 ° C. and in a measurement mode 96 (monitoring time 2.5 minutes / variation width 0.05%). The moisture percentage was measured. The solid content concentration was calculated according to the following formula.
Solid content concentration (% by mass) = 100-M
M: moisture (%) = [(W−W ₀ ) / W] × 100
W: Sample mass before measurement (initial sample mass)
W ₀ : Mass of sample after measurement (absolute dry mass)

[Volume Median Particle Size (D ₅₀ ) and CV Value of Aggregated Particles (1) and Aggregated Particles (2)]
The volume median particle size (D ₅₀ ) of the particles was measured as follows.
・ Measuring machine: "Coulter Multisizer III" (Beckman Coulter, Inc.)
・ Aperture diameter: 50μm
・ Analysis software: “Multisizer III version 3.51” (manufactured by Beckman Coulter)
・ Electrolyte: “Isoton II” (Beckman Coulter, Inc.)
Measurement conditions: 30,000 particles are measured after adjusting the particle size of 30,000 particles to a concentration that can be measured in 20 seconds by adding a sample dispersion containing aggregated particles to 100 mL of the electrolyte. From the particle size distribution, the volume median particle size (D ₅₀ ) was determined.
Moreover, CV value (%) was calculated according to the following formula as particle size distribution.
CV value (%) = (standard deviation of particle size distribution / volume median particle size (D ₅₀ )) × 100

[Volume Median Particle Size (D ₅₀ ) and CV Value of Toner Particles (Fused Particles)]
The volume median particle size of the toner particles (fused particles) was measured as follows.
The measuring instrument, aperture diameter, analysis software, and electrolyte solution were the same as the volume median particle diameter of the aggregated particles.

Dispersion: Polyoxyethylene lauryl ether “Emulgen 109P” (manufactured by Kao Corporation, HLB: 13.6) was dissolved in the electrolytic solution to obtain a dispersion having a concentration of 5% by mass.
-Dispersion condition: 10 mg of a toner measurement sample is added to 5 mL of the dispersion, and dispersed for 1 minute with an ultrasonic disperser, and then 25 mL of electrolyte is added, and further dispersed for 1 minute with an ultrasonic disperser. A sample dispersion was prepared.
Measurement conditions: After adding the sample dispersion to 100 mL of the electrolyte solution, the particle size of 30,000 particles is adjusted to a concentration that can be measured in 20 seconds, and then 30,000 particles are measured. The volume-median particle size (D ₅₀ ) was determined from the distribution.

The CV value (%) was calculated according to the following formula.
CV value (%) = (standard deviation of particle size distribution / volume median particle size (D ₅₀ )) × 100

[Toner fixability evaluation]
Using a commercially available printer “Microline 5400” (Oki Data Co., Ltd.) on high quality paper “J paper A4 size” (Fuji Xerox Co., Ltd.), the toner adhesion amount on the paper is 0.42 to 0.48 mg / cm ^2. The solid image was output without fixing at a length of 50 mm, leaving a margin of 5 mm from the top edge of the A4 paper.
Next, the same printer with the temperature-variable fixing device prepared was prepared, the temperature of the fixing device was set to 90 ° C., and fixing was performed at a speed of 1.5 seconds per sheet in the A4 longitudinal direction, thereby obtaining a printed matter.
In the same manner, the temperature of the fixing device was increased by 5 ° C. and fixed, and a printed matter was obtained.
A 500 g weight is applied to the solid image from the top margin of the printed image and a solid image with a 50 mm long mending tape “Scotch Mending Tape 810” (18 mm wide by 3M). And reciprocally pressed at a speed of 10 mm / sec. Thereafter, the affixed tape was peeled off from the lower end side at a peeling angle of 180 degrees and at a speed of 10 mm / sec to obtain a printed matter after the tape was peeled off. 30 high-quality paper “Excellent White Paper A4 Size” (manufactured by Oki Data Co., Ltd.) is laid under the printed matter before and after the tape is applied, and the reflected image density of the fixed image portion before and after the tape is applied to each printed matter. Measurement was performed using a colorimeter “SpectroEye” (manufactured by GretagMacbeth, Inc., light emission condition: standard light source D ₅₀ , observation visual field 2 °, density reference DINNB, absolute white reference), and the fixing ratio was calculated from the following formula.
Fixing rate (%) = (Reflected image density after peeling tape / Reflected image density before applying tape) × 100
The temperature of the fixing device is increased by 5 ° C., and the test is performed at each fixing temperature in increments of 5 ° C. until the temperature at which a cold offset occurs or the temperature at which the fixing rate is less than 90% is reached. The test was conducted.
Note that cold offset refers to a phenomenon in which toner on an unfixed image does not melt sufficiently and the toner adheres to the fixing roller when the temperature of the fixing device is low. On the other hand, hot offset refers to fixing. This refers to a phenomenon in which toner adheres to the fixing roller when the temperature of the container is high.
The occurrence of cold offset or hot offset can be judged by whether or not toner adheres to the paper again when the fixing roller makes a round. In this test, the solid image on the paper surface is peeled off. In this case, it was determined that the offset was cold, and it was determined that the hot offset occurred when the toner adhered to the fixing roller adhered to the surface of 87 mm from the upper end of the solid image on the sheet.
The lowest temperature among the temperatures at which a cold offset does not occur and the fixing rate is 90% or more is the lowest fixing temperature, and the temperature range from the lowest fixing temperature to a temperature 5 ° C. lower than the temperature at which the hot offset has occurred can be fixed. The range (hereinafter also referred to as “fixing width”) was used. The wider the fixable temperature range, the better the toner is.

[Toner durability evaluation]
The toner is put into the developing cartridge of the non-magnetic one-component developing device “Microline 5400” (manufactured by Oki Data Co., Ltd.). The occurrence of uneven stripes on the roll surface was visually observed, and the time until the occurrence of uneven stripes was measured to determine durability.
In the one-component developing device, the toner is charged by passing through the blade portion. At this time, if the toner is mechanically and physically weak against external factors, it adheres to the blade portion and the developing roll. Occurs and is observed as unevenness. Therefore, a toner having a longer time until occurrence of unevenness is more excellent in durability.

[Supernatant state at the time of fusion]
In a sample obtained by taking 10 g of the fused particle dispersion in a test tube and treating it with a centrifuge at 4000 rpm for 1 minute, the state of the supernatant was visually observed and evaluated according to the following criteria. When the supernatant liquid becomes cloudy, it indicates that the release agent is liberated.
A: The supernatant is transparent B: The supernatant is slightly cloudy C: The supernatant is cloudy

Production Example 1
(Production of polyester A)
The inside of a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 3374 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, Put 33 g of polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, 672 g of terephthalic acid, and 10 g of dibutyltin oxide, and raise the temperature to 230 ° C. with stirring in a nitrogen atmosphere. After maintaining for 5 hours, the pressure in the flask was further lowered and maintained at 8.3 kPa for 1 hour. Then, after cooling to 210 ° C. and returning to atmospheric pressure, 696 g of fumaric acid and 0.49 g of tert-butylcatechol were added and maintained at a temperature of 210 ° C. for 5 hours. Polyester A was obtained by maintaining at 3 kPa for 4 hours.
The glass transition temperature was 65 ° C., the softening point was 107 ° C., and the crystallinity index was 1.5. The acid value was 24 mgKOH / g.
The physical properties of polyester A are shown in Table 1.

Production Example 2
(Production of polyester B)
The inside of a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane 3528 g, poly Oxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane (1404 g), terephthalic acid (1248 g), dodecenyl succinic anhydride (1541 g), and dibutyltin oxide (20 g) were added and stirred at 230 ° C. in a nitrogen atmosphere. The temperature in the flask was maintained at 230 ° C. for 6 hours, and then the pressure in the flask was further reduced and maintained at 8.3 kPa for 1 hour. Then, after cooling to 215 ° C. and returning to atmospheric pressure, 300 g of trimellitic anhydride was added and maintained at 215 ° C. for 1 hour, then the pressure in the flask was further lowered and maintained at 8.3 kPa for 3 hours. Thus, polyester B was obtained.
The glass transition temperature was 57 ° C., the softening point was 118 ° C., and the crystallinity index was 1.7. The acid value was 19 mgKOH / g.
The physical properties of polyester B are shown in Table 1.

Production Example 3
Example of resin particle dispersion production (production of resin particle dispersion a)
In a 2 liter stainless steel kettle, 390.0 g of polyester A, 210.0 g of polyester B, 45 g of copper phthalocyanine pigment “ECB-301” (manufactured by Dainichi Seika Kogyo Co., Ltd.), 15% by weight sodium dodecylbenzenesulfonate aqueous solution “Neopelex” G-15 "(anionic surfactant, Kao Corporation) 40.0 g, polyoxyethylene oleyl ether" Emulgen 430 "(nonionic surfactant, Kao Corporation, HLB: 16.2) 6.0 g, In addition, 278.5 g of a 5% by mass aqueous potassium hydroxide solution was dispersed at 95 ° C. with stirring at 200 r / min with a chi-type stirrer. The mixture was kept for 2 hours under stirring at 200 r / min with a Kai-type stirrer. Subsequently, 1222 g of deionized water was added dropwise at 6 g / min while stirring at 200 r / min with a Kai-type stirrer. The system temperature was maintained at 95 ° C. After dropping, the mixture was cooled to 25 ° C., and 28 g of a polymer containing water-soluble oxazoline group “Epocross WS-700” (manufactured by Nippon Shokubai Co., Ltd.) was added with stirring at 200 r / min with a chi-type stirrer. The temperature was raised to 95 ° C and held at 95 ° C for 1 hour.
After cooling, a finely divided resin particle dispersion a was obtained through a 200 mesh (mesh: 105 μm) wire mesh. The volume-average particle size (D ₅₀ ) of the resin particles in the obtained resin particle dispersion a was 0.18 μm, the CV value was 28%, and the solid content concentration was 31% by mass.

Production Example 4
Example of resin particle dispersion production (production of resin particle dispersion b)
In a 2 liter stainless steel kettle, 390.0 g of polyester A, 210.0 g of polyester B, and anionic surfactant “Neopelex G-15” (manufactured by Kao Corporation, 15% by weight aqueous sodium dodecylbenzenesulfonate) 40 0.0 g, 6.0 g of nonionic surfactant “Emulgen 430” (manufactured by Kao Corporation, polyoxyethylene (26moI) oleyl ether (HLB: 16.2)), and 278.5 g of 5% by mass aqueous potassium hydroxide solution The mixture was dispersed at 95 ° C. with stirring at 200 r / min using a Kai-type stirrer. The mixture was kept for 2 hours under stirring at 200 r / min with a Kai-type stirrer. Subsequently, 1222 g of deionized water was added dropwise at 6 g / min while stirring at 200 r / min with a Kai-type stirrer. The system temperature was maintained at 95 ° C.
After dropping, the mixture was cooled and passed through a 200 mesh (mesh: 105 μm) wire mesh to obtain a finely divided resin particle dispersion b. The resin particles in the obtained resin particle dispersion b had a volume median particle size (D ₅₀ ) of 0.14 μm, a CV value of 24%, and a solid content concentration of 31% by mass.

Production Example 5
Production method of release agent particle dispersion a In a 1 liter beaker, 225 g of deionized water, 2.0 g of 5 mass% potassium hydroxide aqueous solution, paraffin wax “HNP-9” (manufactured by Nippon Seiwa Co., Ltd., melting point 75 ° C. ) 45 g and 5 g of Carnauba wax (manufactured by Hiroyuki Kato, melting point 83 ° C., acid value 5 mg KOH / g) were added and dispersed. The pH at 25 ° C. of this dispersion was measured and found to be 12.5. The dispersion was heated to 95 ° C. to completely dissolve the wax, and then treated with an ultrasonic homogenizer “US-600T” (manufactured by Nippon Seiki Co., Ltd.) for 30 minutes while maintaining the temperature at 90 to 95 ° C. . Then, it cooled to 25 degreeC, deionized water was added, solid content was adjusted to 20 mass%, and the mold release agent dispersion liquid a was obtained. Table 2 shows the physical properties of the obtained release agent dispersion.

Production Example 6
Production method of release agent particle dispersion b In Production Example 5 (production method a), the pH of the dispersion before heating obtained by mixing and dispersing deionized water, a basic compound, and each wax is 11.4. Thus, a release agent dispersion was obtained in the same manner except that 2.0 g of 5 mass% potassium hydroxide aqueous solution was changed to 1.0 g.

Production Example 7
Method for producing release agent particle dispersions c and e Release agent dispersion in the same manner as in Production Example 5 (production method for a) except that the paraffin wax “HNP-9” was changed to the wax shown in the table. Got. The pH of the dispersion before heating was 12.6 in the production of the release agent dispersion c and 12.4 in the production of the release agent dispersion e.

Production Example 8
Production method of release agent particle dispersion d The same as in Production Example 5 (production method of a), except that 2.0 g of 5 mass% aqueous potassium hydroxide solution was changed to 1.4 g of 5 mass% aqueous sodium hydroxide solution. Thus, a release agent dispersion was obtained. The pH of the dispersion before heating was 12.7.

Production Example 9
Production method of release agent particle dispersion f Release agent dispersion liquid in the same manner as in Production Example 5 (production method a) except that the 5 mass% aqueous potassium hydroxide solution was changed to a 25 mass% aqueous ammonia solution. Got. The pH of the dispersion before heating was 11.3.

Production Example 10
Production method of release agent particle dispersion g In Production Example 5 (Production Method a), 2.0 g of 5% by mass potassium hydroxide aqueous solution was changed to 0.2 g of triethylamine in the same manner, A release agent dispersion was obtained. The pH of the dispersion before heating was 12.1.

Production Example 11
Production method of release agent particle dispersion h In Production Example 5 (production method a), a 5% by weight potassium hydroxide aqueous solution was not added, but instead an aqueous sodium polycarboxylate solution “Poise 521” (available from Kao Corporation, effective) A release agent dispersion was obtained in the same manner except that the addition amount was changed to 3.8 g (concentration: 40% by mass). The pH of the dispersion before heating was 10.6.

Production Example 12
Production method of release agent particle dispersion i In production example 5 (production method a), the mixture was changed from mixing 45 g of paraffin wax “HNP-9” and 5 g of carnauba wax to 50 g of paraffin wax “HNP-9”. In the same manner, dispersion treatment was performed, but the release agent was not sufficiently dispersed, and a dispersion liquid could not be obtained. The pH of the dispersion before heating was 12.6.

Production Example 13
Method for producing release agent particle dispersion j In Production Example 5 (Production Method a), a dispersion treatment was carried out in the same manner except that 5% by mass potassium hydroxide aqueous solution was not added. No dispersion was obtained without dispersion. The pH of the dispersion before heating was 7.2.

Production Example 14
Production Method of Release Agent Particle Dispersion k In Production Example 5 (Production Method a), an anionic surfactant “Neopelex G15” (manufactured by Kao Corporation) is used instead of adding a 5% by mass aqueous potassium hydroxide solution. , Sodium dodecylbenzenesulfonate, effective concentration 15% by mass) A release agent dispersion was obtained in the same manner except that the content was changed to 3.3 g. The pH of the dispersion before heating was 7.6.

Production Example 15
Production method of release agent particle dispersion l The same as in Production Example 5 (production method a), except that the 5 mass% potassium hydroxide aqueous solution was changed to a 5 mass% potassium hydroxide / phosphate buffer solution at pH 9. However, the release agent was not dispersed, and a dispersion was not obtained. The pH of the dispersion before heating was 9.1.

Production Example 16
Production method of release agent particle dispersion m In Production Example 5 (production method of a), the mixture was changed from 45 g of paraffin wax “HNP-9” and 5 g of carnauba wax to 50 g of paraffin wax “HNP-9”. A release agent dispersion was obtained in the same manner except that 3.3 g of an anionic surfactant “Neopelex G15” (manufactured by Kao Corporation, sodium dodecylbenzenesulfonate, effective concentration: 15% by mass) was additionally added. The pH of the dispersion before heating was 12.2.

Production Example 17
Production method of release agent particle dispersion n In Production Example 5 (Production Method a), an additional 3.8 g of a sodium polycarboxylate aqueous solution “Poise 521” (manufactured by Kao Corporation, effective concentration 40 mass%) was added. In the same manner, a release agent dispersion was obtained. The pH of the dispersion before heating was 12.7.

  Table 2 shows the pH of the dispersion before heating during the production of the release agent particle dispersion. Table 2 shows the volume-median particle sizes of the obtained release agent particles a to h, k, m, and n.

Example 1
250 g of the resin particle dispersion a, 58 g of deionized water, and 41 g of the release agent particle dispersion a were placed in a 4-liter 2-liter flask equipped with a dehydrating tube, a stirrer, and a thermocouple, and mixed at 25 ° C. Next, an aqueous solution in which 18.2 g of ammonium sulfate was dissolved in 162 g of deionized water was added dropwise to this mixture at 25 ° C. over 30 minutes while stirring with a Kai-type stirrer. Next, the obtained mixed solution was heated to 55 ° C. and held at 55 ° C. to form aggregated particles (1) having a volume median particle size (D ₅₀ ) of 4.0 μm.
Then, the liquid mixture which mixed resin particle dispersion b 23g and deionized water 7.5g as a dispersion liquid of the resin particle (B) was dripped over 60 minutes. This operation was repeated a total of 3 times. Next, as a dispersion of resin particles (B), a mixture of 28 g of resin particle dispersion a and 9.0 g of deionized water and an aqueous solution in which 1.5 g of ammonium sulfate was dissolved in 15 g of deionized water were simultaneously added. It was added dropwise over a period of minutes. This operation was repeated a total of 2 times to obtain an aggregated particle (2) dispersion having a volume median particle size (D ₅₀ ) of 5.0 μm.
An aqueous solution obtained by diluting 11.6 g of polyoxyethylene lauryl ether sodium sulfate “Emal E-27C” (manufactured by Kao Corporation, solid content: 28% by mass) with 450 g of deionized water was added to the obtained aggregated particle (2) dispersion. After the addition, the temperature was raised to 80 ° C. over 2 hours and held for 2 hours, and then fused particles having a volume median particle size (D ₅₀ ) of 5.0 μm were obtained. Then, it cooled to 25 degreeC. During this time, the agglomerated particles (2) changed to fused particles.
The obtained fused particles were subjected to a filtration step for solid-liquid separation, a drying step, and a washing step to obtain toner particles. To 100 parts by mass of the toner particles, 2.5 parts of hydrophobic silica “1RY50” (manufactured by Nippon Aerosil Co., Ltd., number average particle size 0.04 μm), hydrophobic silica “Caboseal TS720” (manufactured by Cabot, number average particles) 1.0 part of diameter 0.012 μm) and 0.8 part of organic fine particles “Finesphere P2000” (manufactured by Nippon Paint Co., Ltd., number average particle diameter 0.5 μm) were externally added with a Henschel mixer, and a 150 mesh sieve was obtained. The fine particles that passed through were used as cyan toner.
Table 2 shows the evaluation results of the state of the supernatant liquid at the time of fusion, and the evaluation results of the obtained toner, such as the type and properties of the release agent particle dispersion used.

Examples 2-7, Comparative Examples 1-7
A toner was obtained in the same manner as in Example 1 except that the release agent particle dispersion was changed to that shown in the table.
Table 2 shows the evaluation results of the state of the supernatant liquid at the time of fusion, and the evaluation results of the obtained toner, such as the type and properties of the release agent particle dispersion used.

  According to the production method of the present invention, since aggregation control is possible with a small particle size at the time of toner production, electrostatic image development suitable for use in electrophotography, electrostatic recording method, electrostatic printing method, etc. Toner can be obtained.

Claims (8)

A method for producing a toner for developing an electrostatic charge image, comprising the following steps (1) to (3):
Step (1): A release agent (a) containing an ester wax (a1) having an acid value of 1 mgKOH / g to 10 mgKOH / g and a release agent (a2) other than the ester wax (a1), pH 9. 5 to 14 and under conditions where no surfactant is added or the surfactant content is 0.5 parts by mass or less with respect to 100 parts by mass of the total amount of the release agent (a). Step (2) of preparing release agent particles by dispersing: Step of obtaining aggregated particles by mixing the release agent particles, resin particles, and flocculant obtained in step (1) in an aqueous medium. (3): a step of fusing the aggregated particles obtained in step (2) to obtain fused particles   The method for producing a toner for developing an electrostatic charge image according to claim 1, wherein the ester wax (a1) is carnauba wax.   The method for producing a toner for developing an electrostatic charge image according to claim 1, wherein the release agent (a2) contains a hydrocarbon wax.   The method for producing a toner for developing an electrostatic charge image according to claim 3, wherein the hydrocarbon wax has a melting point of 100 ° C. or less.   The method for producing a toner for developing an electrostatic image according to claim 1, wherein the resin particles contain polyester.   The method for producing a toner for developing an electrostatic charge image according to any one of claims 1 to 5, wherein the content of the ester wax (a1) in the release agent (a) is 1% by mass or more and 49% by mass or less. .   The mass ratio [ester wax (a1) / release agent (a2)] of the ester wax (a1) to the release agent (a2) is 1/99 to 49/51. A method for producing a toner for developing an electrostatic image as described in 1.   The method for producing a toner for developing an electrostatic charge image according to any one of claims 1 to 7, wherein a basic compound is used to adjust the pH to 11 or more and 14 or less in the step (1).