JP7164367B2 - Method for producing toner for electrostatic charge image development - Google Patents

Description

The present invention relates to a method for producing an electrostatic charge image developing toner used for developing a latent image formed by an electrophotography method, an electrostatic recording method, an electrostatic printing method, or the like.

In the field of electrophotography, with the development of electrophotographic systems, there is a demand for the development of electrophotographic toners capable of achieving higher image quality and higher speed. As a method of obtaining a fixing toner that has a narrow particle size distribution and a small particle size and that can be used at high speeds for high image quality, fine resin particles are aggregated and fused in an aqueous medium. 2. Description of the Related Art So-called chemical toners are produced by aggregation fusion methods (emulsion aggregation method, aggregation coalescence method) to obtain toner.

In Patent Document 1, in an electrophotographic toner containing a crystalline resin having at least one or more melting points, the proportion of metal atoms that can have a valence of 2 or more among all the metal atoms on the surface of the toner is disclosed. A toner for electrostatic charge image development, characterized in that (A) and the ratio (B) of alkali metal atoms having a univalent valence are in a ratio of 0.23≦A/(A+B)≦0.98. is described. The toner is described as capable of obtaining high image quality and having a sharp particle size distribution.

Patent Document 2 discloses a dispersion step of producing an aqueous dispersion of polyester resin particles, an ammonium compound addition step of adding an ammonium compound to the aqueous dispersion, and an aggregation step of forming aggregated particles containing the polyester resin particles. and a fusing step of fusing the aggregated particles to form toner particles. It is described that the toner has stable charging characteristics even in a low-humidity environment even when the toner is produced by an aggregation method using an aqueous dispersion of polyester resin particles produced without using an organic solvent. .

Japanese Patent Application Laid-Open No. 2003-162093 JP 2017-58551 A

In contrast to the toners of Patent Literatures 1 and 2, further improvement in low-temperature fixability of toners is demanded due to the remarkable increase in speed in electrophotographic systems in recent years.
On the other hand, it is difficult to obtain a toner for electrostatic image development that exhibits excellent low-temperature fixability and excellent hot-offset resistance.
TECHNICAL FIELD The present invention relates to a method for producing an electrostatic charge image developing toner that exhibits excellent low-temperature fixability and a wide non-offset temperature range.

In order to solve such problems, the inventors of the present invention used a combination of predetermined types of cations as a flocculating agent at the time of flocculation. It has been found that a toner for image development can be obtained.
The present invention comprises a first aggregating step of aggregating resin particles X containing an amorphous polyester resin A in an aqueous medium to obtain aggregated particles, and
A fusing step of fusing the obtained aggregated particles,
In the first aggregation step, adding a monovalent cation (a) and a divalent or higher metal cation (b),
A method for producing a toner for electrostatic charge image development, wherein the amount of the cation (b) added is 0.5 mol % or more and 5 mol % or less with respect to the total amount of the cation (a) and the cation (b). Regarding.

According to the present invention, it is possible to provide a method for producing an electrostatic charge image developing toner that exhibits excellent low-temperature fixability and a wide non-offset temperature range.

[Manufacturing Method of Toner for Developing Electrostatic Charge Image]
The method for producing the toner for electrostatic charge image development of the present invention (hereinafter also simply referred to as "toner") comprises:
First, resin particles X (hereinafter simply referred to as "resin particles X") containing an amorphous polyester resin A (hereinafter simply referred to as "resin A") are aggregated in an aqueous medium to obtain aggregated particles. agglomeration step, and
A fusing step of fusing the obtained aggregated particles is included.
Then, in the first aggregation step, a monovalent cation (a) (hereinafter simply referred to as "cation (a)") and a divalent or higher metal cation (b) (hereinafter simply referred to as "cation (b)") ) is added.
The amount of cation (b) added is 0.5 mol % or more and 5 mol % or less with respect to the total amount of cation (a) and cation (b).
By the above method, a toner having excellent low-temperature fixability and a wide non-offset temperature range can be obtained.

Although the reason is not clear, it is considered as follows.
The inventor focused on a method for improving the elasticity of chemical toner in order to obtain a toner that exhibits excellent low-temperature fixability and a wide non-offset temperature range. As a result, instead of conventional methods such as increasing the molecular weight of the polyester resin or adding a cross-linking agent, in the aggregation process, a monovalent cation (a) and a predetermined amount of divalent or higher metal cations ( It has been found that by adding b), a toner having excellent low-temperature fixability and exhibiting a wide non-offset temperature range can be obtained. It is presumed that this effect is obtained by improving the elasticity of the toner by forming an ionic bond between the metal cation (b) having a valence of 2 or more and the polyester.
The metal cation (b) binds to the terminal carboxyl group of the polyester resin in the toner. At this time, the use of the metal cation (b) having a valence of 2 or more causes the polyester resin to be crosslinked, and substantially to form a cross-link. However, since the bond is an ionic bond, unlike a covalent bond, its bonding strength is rather weak. Furthermore, since it is added as a cation at the time of aggregation, it forms a bond only with the carboxy group of the polyester resin that has dissociated in water. That is, the low-molecular-weight portion of the polyester-based resin preferentially forms a bond.
In toner fixing, high-temperature offset is caused by a portion that has a low viscosity at high temperatures, that is, a low-molecular-weight component. It is considered that when a crosslinked structure is introduced, the high-temperature offset is suppressed by cross-linking the low-molecular-weight portion and suppressing the decrease in viscosity. Furthermore, since the bond is not as strong as a covalent bond, it is considered that the cross-linking is performed while suppressing the influence on the low-temperature fixability.

Definitions of various terms used in this specification are shown below.
Whether a resin is crystalline or amorphous is determined by the crystallinity index. The crystallinity index is defined as the ratio of the softening point of the resin to the maximum endothermic peak temperature (softening point (°C)/maximum endothermic peak temperature (°C)) in the measurement method described in the Examples below. A crystalline resin has a crystallinity index of 0.6 or more and 1.4 or less. Amorphous resins are those having a crystallinity index of less than 0.6 or greater than 1.4. The crystallinity index can be appropriately adjusted depending on the type and ratio of raw material monomers, and production conditions such as reaction temperature, reaction time, and cooling rate.
In the specification, the carboxylic acid component of the polyester resin includes not only the compound but also an anhydride that decomposes during the reaction to generate an acid, and an alkyl ester of each carboxylic acid (the number of carbon atoms in the alkyl group is 1 or more and 3 or less). is also included.
"Volume-median particle size ( _D50 )" is a particle size at which the cumulative volume frequency calculated as a volume fraction is 50%, calculated from the smaller particle size.
The coefficient of variation of particle size distribution (hereinafter also simply referred to as “CV value”) is a value represented by the following formula. The volume average particle size in the following formula is the particle size obtained by multiplying the particle size measured on a volume basis by the ratio of particles having that particle size value, and dividing the resulting value by the number of particles. be.
CV value (%) = [standard deviation of particle size distribution (μm)/volume average particle size (μm)] × 100

<First aggregation step>
In this production method, a monovalent cation (a) and a divalent or higher metal cation (b) are added in the first aggregation step. The cation (a) is added from the viewpoint of controlling aggregation of the resin particles X. The cation (b) is added from the viewpoint of widening the non-offset temperature range of the resulting toner.
From the viewpoint of obtaining a toner having excellent low-temperature fixability and a wide non-offset temperature range, the amount of cation (b) added is smaller than the amount of cation (a) added on a molar basis.
The amount of cation (b) added is 0.5 mol % with respect to the total amount of cation (a) and cation (b), from the viewpoint of further improving low-temperature fixability and widening the non-offset temperature range. above, preferably 0.8 mol% or more, more preferably 1 mol% or more, and 5 mol% or less, preferably 4 mol% or less, further preferably 3 mol% or less, still more preferably 2 mol% or less is.
In the first aggregation step, for example, cation (a) and cation (b) are added to a mixed dispersion containing resin particles X, and resin particles X are aggregated in an aqueous medium to obtain aggregated particles 1. Furthermore, from the viewpoint of promoting aggregation, it is preferable to raise the temperature of the dispersion after adding the aggregating agent.
Examples of forms in which the cation (a) and the cation (b) are added include:
(i) a form in which a salt containing cation (a) and a salt containing cation (b) are added;
(ii) form in which a salt containing cation (a) and metal cation (b) is added;
(iii) a form in which a salt containing cation (a), a salt containing cation (b), and a salt containing cation (a) and metal cation (b) are added;
is mentioned.

The cations (a) and cations (b) are concepts including cations derived from salts added in the first aggregation step. For example, salts added as flocculants, pH adjusters, surfactants, etc. In some cases, cations contained in flocculants, cations contained in pH adjusters, and cations contained in surfactants are also included.

[Monovalent cation (a)]
Examples of cations (a) include alkali metal ions such as ammonium ions, sodium ions and potassium ions. Among these, ammonium ions are preferred.
Examples of raw materials for the cation (a) include salts containing the cation (a) and other pH adjusters.
Salts containing cation (a) include, for example, flocculants and ionic surfactants.
Examples of flocculants include inorganic ammonium salts such as ammonium sulfate, ammonium chloride and ammonium nitrate; monovalent inorganic metal salts such as sodium sulfate, sodium nitrate, sodium chloride, potassium nitrate, potassium sulfate and potassium chloride. Among these, inorganic ammonium salts are preferred, and ammonium sulfate is more preferred.
Examples of ionic surfactants include anionic surfactants and cationic surfactants. Anionic surfactants include, for example, dodecyl benzene sulfonate, dodecyl sulfate, lauryl ether sulfate, and alkenyl succinate. Examples of cationic surfactants include alkyltrimethylammonium chloride and benzalkonium chloride.
Other pH adjusters include, for example, basic substances and acidic substances. Basic substances include, for example, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; and nitrogen-containing basic substances such as ammonia, trimethylamine and diethanolamine. Acidic substances include sulfuric acid, nitric acid, and hydrochloric acid.
Among these, flocculants are preferred.
In the cation (a) to be added, the ratio of the cation (a) of the flocculant is preferably 80 mass% or more, more preferably 85 mol% or more, still more preferably 90 mol% or more, and preferably 100 mol % or less, more preferably 99 mol % or less, still more preferably 98 mol % or less.

The amount of cation (a) added is preferably 95% by mass with respect to the total amount of cation (a) and cation (b), from the viewpoint of further improving low-temperature fixability and widening the non-offset temperature range. Above, more preferably 96 mol% or more, still more preferably 97 mol% or more, and preferably 99.5 mol% or less, more preferably 99.2 mol% or less, still more preferably 99 mol% or less .
The molar amount of the cation (a) to be added is preferably 200 mmol or more, more preferably 300 mmol or more, and still more preferably 300 mmol or more, relative to 100 g of the resin, from the viewpoint of further improving the low-temperature fixability and widening the non-offset temperature range. It is 400 mmol or more, and preferably 800 mmol or less, more preferably 700 mmol or less, still more preferably 600 mmol or less.

From the viewpoint of further improving the low-temperature fixability and widening the non-offset temperature range, the addition amount of the flocculant as the raw material of the cation (a) is preferably It is 5 parts by mass or more, more preferably 10 parts by mass or more, still more preferably 20 parts by mass or more, and preferably 50 parts by mass or less, more preferably 45 parts by mass or less, still more preferably 40 parts by mass or less.

The cation (a) is preferably added as an aqueous solution of the raw material of the cation (a).
The concentration of the aqueous solution of the raw material of the cation (a) is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, and preferably 20% by mass or less, more preferably It is 15% by mass or less, more preferably 10% by mass or less.
The pH of the aqueous solution of the raw material of the cation (a) is preferably 7.0 or higher, more preferably 7.5 or higher, still more preferably 8.0 or higher, and preferably 10.0 or lower, more preferably It is 9.5 or less, more preferably 9.0 or less.

[Divalent or higher metal cation (b)]
Examples of cations (b) include magnesium ions, calcium ions, aluminum ions, iron (II) ions, and iron (III) ions. Among these, aluminum ions and iron (III) ions are preferred, and iron (III) ions are more preferred.
Salts containing cation (b) include, for example, magnesium sulfate, magnesium nitrate, magnesium chloride, calcium sulfate, calcium nitrate, calcium chloride, aluminum sulfate, aluminum nitrate, aluminum chloride, iron (II) chloride, iron (II) sulfate , iron (II) nitrate, iron (III) sulfate, iron (III) nitrate, iron (III) chloride. Among these, aluminum sulfate, iron(III) chloride, and magnesium sulfate are preferable, and from the viewpoint of widening the non-offset temperature range, aluminum sulfate and iron(III) chloride are more preferable, and iron(III) chloride is even more preferable.

The amount of the salt containing the cation (b) to be added is preferably 0.1 parts by mass with respect to 100 parts by mass of the total amount of the resin components, from the viewpoint of further improving the low-temperature fixability and widening the non-offset temperature range. parts or more, more preferably 0.5 parts by mass or more, still more preferably 0.8 parts by mass or more, and preferably 6 parts by mass or less, more preferably 3 parts by mass or less, and still more preferably 2 parts by mass or less. be.
The molar amount of the cation (b) added is preferably 1 mmol or more, more preferably 3 mmol or more, and even more preferably 4 mmol or more per 100 g of the resin, from the viewpoint of further widening the non-offset temperature range. is preferably 30 mmol or less, more preferably 20 mmol or less, and even more preferably 10 mmol or less, from the viewpoint of further improving the

In this production method, the valence B of the cation (b), the added mole number C of the cation (b), and the mole number A of the carboxy group in the amorphous polyester resin A of the resin particles X are represented by the following formula: It has the relationship of (1).
0.2 < (B x C)/A < 1 (1)
[In the formula, B is the valence of the cation (b), C is the number of moles of the cation (b) added (unit: mol), and A is the amorphous polyester resin A of the resin particles X is the number of moles (unit: mol) of carboxy groups in the ]
In the above formula (1), "B × C" is a multiplier of the valence of the cation (b) and the number of added moles, so it indicates the number of moles that can be ionically combined with the polyester resin A. there is Since the number obtained by dividing this by A, ie, the carboxy group of the polyester resin A, is the amount relative to the carboxy group, (B×C)/A is the ratio of the salt capable of ionically complexing with the carboxy group. When (B×C)/A is less than 1, it is believed that ionic bonds are effectively formed, leading to improved high-temperature offset.

(B×C)/A is preferably 0.3 or more, more preferably 0.4 or more, and still more preferably 0.5 or more from the viewpoint of widening the non-offset temperature range. From the viewpoint of further improvement, it is preferably 0.9 or less, more preferably 0.8 or less, still more preferably 0.7 or less, and even more preferably 0.6 or less.

樹脂Ａの酸価は、実施例に記載の方法により測定された値である。なお、ここで樹脂Ａの酸価は、樹脂Ａが中和されている場合、中和される前の酸価である。 The number of moles A (unit: mol) of carboxy groups in resin A is a value calculated from the following formula.

The acid value of Resin A is a value measured by the method described in Examples. In addition, the acid value of resin A is an acid value before neutralization, when resin A is neutralized here.

Cation (b) is preferably added as an aqueous solution of a salt containing cation (b).
The concentration of the aqueous salt solution containing the cation (b) is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, and preferably 30% by mass or less, more preferably It is 20% by mass or less, more preferably 15% by mass or less.

Salts containing cation (a) and cation (b) include, for example, aluminum potassium sulfate, aluminum sodium sulfate, aluminum ammonium sulfate, magnesium ammonium sulfate, magnesium potassium chloride, and sodium ferrous citrate.
When a salt containing these cations (a) and cation (b) is used, a salt containing cation (a) or a salt containing cation (b) is further added, and the amount of cation (b) added, added It is preferable to adjust the concentration.

The total amount of the salt containing the cation (a), the salt containing the cation (b), and the salt containing the cation (a) and the cation (b) is preferably It is 5 parts by mass or more, more preferably 10 parts by mass or more, still more preferably 20 parts by mass or more, and preferably 60 parts by mass or less, more preferably 50 parts by mass or less, and still more preferably 40 parts by mass or less.
As for the order of addition of the cation (a) and the cation (b), the cation (b) is preferably added after the total amount of the cation (a) is added.
The temperature of the mixed dispersion when adding the cation (a) and the cation (b) is preferably 0° C. or higher, more preferably 10° C. or higher, still more preferably 20° C. or higher, and preferably 40° C. or lower. , more preferably 35° C. or lower, still more preferably 30° C. or lower.
From the viewpoint of promoting aggregation, it is preferable to raise the temperature of the dispersion after adding the cation (a) and the cation (b). At that time, the temperature is preferably 10° C. or higher, more preferably 20° C. or higher, still more preferably 30° C. or higher, and preferably 50° C. higher than the temperature at which the cation (a) and the cation (b) are added. Thereafter, the temperature is preferably raised to 45° C. or lower, more preferably 40° C. or lower.

Examples of the conditions of the fusing process for fusing the obtained aggregated particles are the same as in the process (3) described later.

In a method for producing a toner according to one embodiment of the present invention, for example, resin particles X containing an amorphous polyester resin A are aggregated by adding cations (a) and cations (b) in an aqueous medium. a first aggregation step (hereinafter also referred to as “step (1)”) to obtain aggregated particles 1 by
Second, resin particles Y (hereinafter simply referred to as "resin particles Y") containing an amorphous polyester resin B (hereinafter also simply referred to as "resin B") are attached to aggregated particles 1 to obtain aggregated particles 2. Aggregation step (hereinafter also referred to as “step (2)”), and
A fusing step of fusing the obtained aggregated particles (hereinafter also referred to as “step (3)”) is included.
Note that the second aggregation step is optional, and toner particles having a core-shell structure can be obtained through the second aggregation step. At this time, the resin aggregated in the first aggregation step is contained in the core, and the resin aggregated in the second aggregation step is contained in the shell.
The present invention will be described below by taking the embodiment as an example.

<Step (1)>
In step (1), aggregated particles 1 are obtained by adding cation (a) and cation (b) to resin particles X containing amorphous polyester resin A in an aqueous medium to aggregate them.

[Resin particle X]
The resin particles X contain an amorphous polyester-based resin A.
From the viewpoint of further improving the low-temperature fixability, the resin particles X preferably contain the amorphous polyester resin A and the crystalline polyester resin C in the same or different resin particles, more preferably the amorphous polyester resin particles. Resin A and crystalline polyester resin C are contained in the same resin particles.

<<Amorphous polyester resin A>>
Amorphous polyester resin A contains, for example, a polycondensate of an alcohol component and a carboxylic acid component.
The amorphous polyester resin A is preferably a composite containing a polyester resin segment that is a polycondensate of an alcohol component and a carboxylic acid component and a vinyl resin segment that is an addition polymer of a raw material monomer containing a styrene compound. Resin.

（式中、ＯＲ¹及びＲ²Ｏはオキシアルキレン基であり、Ｒ¹及びＲ²はそれぞれ独立にエチレン基又はプロピレン基であり、ｘ及びｙはアルキレンオキサイドの平均付加モル数を示し、それぞれ正の数であり、ｘとｙの和の値は、１以上、好ましくは１．５以上であり、１６以下、好ましくは８以下、より好ましくは４以下である）で表されるビスフェノールＡのアルキレンオキサイド付加物である。
ビスフェノールＡのアルキレンオキサイド付加物としては、例えば、ビスフェノールＡ〔２，２－ビス（４－ヒドロキシフェニル）プロパン〕のプロピレンオキサイド付加物、ビスフェノールＡのエチレンオキサイド付加物が挙げられる。これらは、１種又は２種以上を用いてもよい。これらの中でも、ビスフェノールＡのプロピレンオキサイド付加物が好ましい。
ビスフェノールＡのアルキレンオキサイド付加物の含有量は、アルコール成分中、好ましくは７０モル％以上、より好ましくは９０モル％以上、更に好ましくは９５モル％以上であり、そして、１００モル％以下であり、更に好ましくは１００モル％である。 Examples of alcohol components include aromatic diols, linear or branched aliphatic diols, alicyclic diols, and polyhydric alcohols having a valence of 3 or more. Among these, aromatic diols are preferred.
The aromatic diol is preferably an alkylene oxide adduct of bisphenol A, more preferably of formula (I):

(Wherein, OR ¹ and R ² O are oxyalkylene groups, R ¹ and R ² are each independently an ethylene group or a propylene group, x and y represent the average number of added moles of alkylene oxide, each positive and the sum of x and y is 1 or more, preferably 1.5 or more, and 16 or less, preferably 8 or less, more preferably 4 or less). It is an oxide adduct.
The alkylene oxide adducts of bisphenol A include, for example, propylene oxide adducts of bisphenol A [2,2-bis(4-hydroxyphenyl)propane] and ethylene oxide adducts of bisphenol A. These may be used alone or in combination of two or more. Among these, the propylene oxide adduct of bisphenol A is preferred.
The content of the alkylene oxide adduct of bisphenol A is preferably 70 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol% or less, in the alcohol component, More preferably, it is 100 mol %.

Examples of linear or branched aliphatic diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol and 1,4-butanediol. , 2,3-butanediol, 2,2-dimethyl-1,3-propanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1 , 12-dodecanediol.
Examples of alicyclic diols include hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane], alkylene oxide adducts of hydrogenated bisphenol A having 2 to 4 carbon atoms (average number of moles added: 2 above and below 12).
Examples of trihydric or higher polyhydric alcohols include glycerin, pentaerythritol, trimethylolpropane, and sorbitol.
One or more of these alcohol components may be used.

Examples of the carboxylic acid component include dicarboxylic acids and polycarboxylic acids having a valence of 3 or more.
Dicarboxylic acids include, for example, aromatic dicarboxylic acids, linear or branched aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. Among these, at least one selected from aromatic dicarboxylic acids and linear or branched aliphatic dicarboxylic acids is preferred.
Examples of aromatic dicarboxylic acids include phthalic acid, isophthalic acid, and terephthalic acid. Among these, isophthalic acid and terephthalic acid are preferred, and terephthalic acid is more preferred.
The amount of the aromatic dicarboxylic acid in the carboxylic acid component is preferably 20 mol% or more, more preferably 30 mol% or more, still more preferably 40 mol% or more, still more preferably 50 mol% or more, and preferably It is 90 mol % or less, more preferably 85 mol % or less, still more preferably 80 mol % or less.

The number of carbon atoms in the linear or branched aliphatic dicarboxylic acid is preferably 2 or more, more preferably 3 or more, and preferably 30 or less, more preferably 20 or less.
Linear or branched aliphatic dicarboxylic acids include, for example, oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid, and azelaic acid. , and succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms. Examples of the succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms include dodecylsuccinic acid, dodecenylsuccinic acid, and octenylsuccinic acid. Among these, fumaric acid, sebacic acid, and succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms are preferred.
The amount of linear or branched aliphatic dicarboxylic acid in the carboxylic acid component is preferably 1 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more, and preferably 80 mol%. Below, more preferably 50 mol % or less, still more preferably 30 mol % or less.

The trivalent or higher polyvalent carboxylic acid is preferably a trivalent carboxylic acid, such as trimellitic acid. Preferred is trimellitic acid or its anhydride.
When a trivalent or higher polycarboxylic acid is contained, the amount of the trivalent or higher polycarboxylic acid is preferably 3 mol% or more, more preferably 5 mol% or more, and still more preferably 8 mol% in the carboxylic acid component. and preferably 30 mol % or less, more preferably 25 mol % or less, still more preferably 20 mol % or less.
One or more of these carboxylic acid components may be used.

The equivalent ratio of the carboxy group of the carboxylic acid component to the hydroxyl group of the alcohol component [COOH group/OH group] is preferably 0.7 or more, more preferably 0.8 or more, and preferably 1.3 or less, or more. It is preferably 1.2 or less.

The addition polymerized resin segment is, for example, an addition polymer of raw material monomers containing styrene compounds.
Styrenic compounds include, for example, unsubstituted or substituted styrene. Examples of the substituent with which styrene is substituted include an alkyl group having 1 to 5 carbon atoms, a halogen atom, an alkoxy group having 1 to 5 carbon atoms, a sulfonic acid group, or a salt thereof.
Styrenic compounds include, for example, styrene, methylstyrene, α-methylstyrene, β-methylstyrene, tert-butylstyrene, chlorostyrene, chloromethylstyrene, methoxystyrene, styrenesulfonic acid and salts thereof. Among these, styrene is preferred.
The content of the styrenic compound in the raw material monomers of the addition polymerized resin segment is preferably 50% by mass or more, more preferably 65% by mass or more, still more preferably 75% by mass or more, and preferably 100% by mass or less. is 95% by mass or less, more preferably 90% by mass or less, and still more preferably 85% by mass or less.

Examples of raw material monomers other than styrene compounds include (meth)acrylic acid esters such as alkyl (meth)acrylate, benzyl (meth)acrylate, and dimethylaminoethyl (meth)acrylate; olefins; halovinyls such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as methyl vinyl ether; vinylidene halides such as vinylidene chloride; . Among these, (meth)acrylic acid esters are preferred, and alkyl (meth)acrylates are more preferred.
The number of carbon atoms in the alkyl group in the alkyl (meth)acrylate is preferably 1 or more, more preferably 6 or more, still more preferably 10 or more, and is preferably 24 or less, more preferably 22 or less, and still more preferably 20. It is below.
Examples of alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, (iso)propyl (meth)acrylate, (iso- or tertiary) butyl (meth)acrylate, (meth)acrylate, ) (iso)amyl acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (iso)octyl (meth)acrylate, (iso)decyl (meth)acrylate, (meth)acrylic acid ( iso) dodecyl, (iso) palmityl (meth) acrylate, (iso) stearyl (meth) acrylate, (iso) behenyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate or (meth) Stearyl acrylate is preferred, and stearyl (meth)acrylate is more preferred.
In addition, "(iso or tertiary)" and "(iso)" mean both when these prefixes exist and when they do not exist, and when these prefixes do not exist, normal is indicated. Moreover, "(meth)acrylic acid" indicates acrylic acid or methacrylic acid.

The (meth)acrylic acid ester content in the raw material monomers of the addition polymerized resin segment is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 15% by mass or more, and preferably 50% by mass or more. % by mass or less, more preferably 35% by mass or less, and even more preferably 25% by mass or less.

The total amount of the styrenic compound and the (meth)acrylic acid ester in the raw material monomers of the addition polymerized resin segment is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and even more preferably. is 100% by mass.

The composite resin preferably has structural units derived from bi-reactive monomers that are covalently bonded to the polyester resin segment and the addition polymerized resin segment.
The “structural unit derived from a bireactive monomer” means a unit obtained by reacting a functional group and an addition polymerizable group of a bireactive monomer.
Addition polymerizable groups include, for example, carbon-carbon unsaturated bonds.
The bi-reactive monomers include, for example, addition polymerizable monomers having at least one functional group selected from a hydroxyl group, a carboxyl group, an epoxy group, a primary amino group and a secondary amino group in the molecule. . Among these, addition polymerizable monomers having at least one functional group selected from a hydroxyl group and a carboxy group are preferred, and addition polymerizable monomers having a carboxy group are more preferred, from the viewpoint of reactivity.
Addition-polymerizable monomers having a carboxy group include, for example, acrylic acid, methacrylic acid, fumaric acid, and maleic acid. Among these, acrylic acid and methacrylic acid are preferred, and acrylic acid is more preferred, from the viewpoint of reactivity in both polycondensation reaction and addition polymerization reaction.
The amount of the structural unit derived from the bi-reactive monomer is preferably 1 mol part or more, more preferably 5 mol parts or more, and still more preferably 8 mol parts per 100 mol parts of the alcohol component of the polyester resin segment of the composite resin A. and preferably 30 mol parts or less, more preferably 25 mol parts or less, still more preferably 20 mol parts or less.

The content of the polyester resin segment in the composite resin is preferably 35% by mass or more, more preferably 45% by mass or more, still more preferably 50% by mass or more, and preferably 90% by mass or less, more preferably 85% by mass. % by mass or less, more preferably 75% by mass or less.

The content of the addition polymerized resin segment in the composite resin is preferably 5% by mass or more, more preferably 15% by mass or more, still more preferably 25% by mass or more, and preferably 60% by mass or less, more preferably It is 55% by mass or less, more preferably 45% by mass or less.

The amount of the structural unit derived from the bi-reactive monomer in the composite resin is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, still more preferably 0.8% by mass or more, and preferably is 10% by mass or less, more preferably 5% by mass or less, and still more preferably 3% by mass or less.

The total amount of the polyester resin segment, the addition polymerization resin segment, and the structural units derived from the bi-reactive monomer in the composite resin is preferably 80% by mass or more, more preferably 90% by mass or more, and still more preferably 95% by mass or more. , and not more than 100% by mass, and more preferably 100% by mass.

Polyester-based resin A may be produced, for example, by a method including step A of polycondensing an alcohol component and a carboxylic acid component.

In step A, an esterification catalyst such as di(2-ethylhexanoic acid)tin (II), dibutyltin oxide, titanium diisopropylate bistriethanolamine, etc. is added to the alcohol component and the carboxylic acid component in a total amount of 100, if necessary. 0.01 parts by mass or more and 5 parts by mass or less per part by mass; Esterification promoter such as gallic acid (same as 3,4,5-trihydroxybenzoic acid), total amount of alcohol component and carboxylic acid component is 100 mass 0.001 parts by mass or more and 0.5 parts by mass or less may be used for polycondensation.
Further, when a monomer having an unsaturated bond such as fumaric acid is used for polycondensation, it is preferably 0.001 part by mass or more with respect to 100 parts by mass as the total amount of the alcohol component and the carboxylic acid component, if necessary. A radical polymerization inhibitor of 0.5 parts by mass or less may be used. Examples of radical polymerization inhibitors include 4-tert-butylcatechol.
The temperature of the polycondensation reaction is preferably 120° C. or higher, more preferably 160° C. or higher, still more preferably 180° C. or higher, and preferably 250° C. or lower, more preferably 240° C. or lower. In addition, you may perform polycondensation in an inert gas atmosphere.

The composite resin may be produced, for example, by a method including a step A of polycondensing an alcohol component and a carboxylic acid component, and a step B of addition polymerizing a raw material monomer of an addition polymerized resin segment and a bi-reactive monomer.
Process B may be performed after process A, process A may be performed after process B, or process A and process B may be performed simultaneously.
In step A, a part of the carboxylic acid component is subjected to a polycondensation reaction, and then step B is performed, and then the remainder of the carboxylic acid component is added to the polymerization system to perform the polycondensation reaction of step A and, if necessary, both reactions. A method of further advancing the reaction with the organic monomer is preferred.
The conditions for step A are as described above.

Examples of the radical polymerization initiator for addition polymerization in step B include peroxides such as dibutyl peroxide, persulfates such as sodium persulfate, and 2,2′-azobis(2,4-dimethylvaleronitrile). azo compounds.
The amount of the radical polymerization initiator to be used is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the raw material monomer for the addition polymerization resin segment.
The addition polymerization temperature is preferably 110° C. or higher, more preferably 130° C. or higher, and preferably 230° C. or lower, more preferably 220° C. or lower, still more preferably 210° C. or lower.

(Physical properties of resin A)
The softening point of Resin A 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 non-offset temperature range, and from the viewpoint of further improving low-temperature fixability. , preferably 150° C. or lower, more preferably 140° C. or lower, and still more preferably 125° C. or lower.
The glass transition temperature of Resin A is preferably 30° C. or higher, more preferably 35° C. or higher, and still more preferably 40° C. or higher, from the viewpoint of widening the non-offset temperature range, and from the viewpoint of further improving low-temperature fixability. Therefore, the temperature is preferably 80° C. or lower, more preferably 70° C. or lower, and still more preferably 60° C. or lower.

The acid value of Resin A is preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, still more preferably 15 mgKOH/g or more, and preferably 40 mgKOH/g or less, more preferably 35 mgKOH/g or less, and further preferably Preferably, it is 30 mgKOH/g or less.
The softening point, glass transition temperature, and acid value of Resin A can be appropriately adjusted depending on the type and amount of raw material monomers used, and production conditions such as reaction temperature, reaction time, and cooling rate. is determined by the method described in Examples.
When two or more resins A are used in combination, the softening point, glass transition temperature and acid value of the mixture are preferably within the ranges described above.

The content of the resin A is preferably 40% by mass or more, more preferably 50% by mass or more, still more preferably 60% by mass or more, and 100% by mass, relative to the total amount of the resin components of the resin particles X. or less, preferably 95% by mass or less, more preferably 90% by mass or less, still more preferably 85% by mass or less, still more preferably 80% by mass or less, and even more preferably 75% by mass or less.

<<Crystalline polyester resin C>>
Crystalline polyester resin C is a polycondensate of an alcohol component and a carboxylic acid component.
As the alcohol component, α,ω-aliphatic diols are preferred.
The number of carbon atoms in the α,ω-aliphatic diol is preferably 2 or more, more preferably 4 or more, still more preferably 6 or more, and preferably 16 or less, more preferably 14 or less, still more preferably 12 or less. be.
Examples of α,ω-aliphatic diols include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, and 1,14-tetradecanediol mentioned. Among these, 1,6-hexanediol, 1,10-decanediol and 1,12-dodecanediol are preferred, and 1,10-decanediol is more preferred.

The amount of the α,ω-aliphatic diol in the alcohol component is preferably 80 mol% or more, more preferably 85 mol% or more, still more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol % or less, more preferably 100 mol %.

The alcohol component may contain other alcohol components different from the α,ω-aliphatic diol. Examples of other alcohol components include aliphatic diols other than α,ω-aliphatic diols such as 1,2-propanediol and neopentyl glycol; aromatic diols such as alkylene oxide adducts of bisphenol A; Trihydric or higher alcohols such as erythritol and trimethylolpropane are included. One or more of these alcohol components may be used.

As the carboxylic acid component, aliphatic dicarboxylic acids are preferable, and linear aliphatic dicarboxylic acids are more preferable.
The number of carbon atoms in the aliphatic dicarboxylic acid is preferably 4 or more, more preferably 8 or more, still more preferably 10 or more, and preferably 14 or less, more preferably 12 or less.
Aliphatic dicarboxylic acids include, for example, fumaric acid, sebacic acid, dodecanedioic acid, and tetradecanedioic acid. Among these, sebacic acid and dodecanedioic acid are preferred, and sebacic acid is more preferred. One or more of these carboxylic acid components may be used.

The amount of the aliphatic dicarboxylic acid in the carboxylic acid component is preferably 80 mol% or more, more preferably 85 mol% or more, still more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol % or less, more preferably 100 mol %.

The carboxylic acid component may contain other carboxylic acid components different from the aliphatic dicarboxylic acid. Other carboxylic acid components include, for example, aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid; and trivalent or higher polyvalent carboxylic acids. One or more of these carboxylic acid components may be used.

The equivalent ratio of the carboxy group of the carboxylic acid component to the hydroxyl group of the alcohol component [COOH group/OH group] is preferably 0.7 or more, more preferably 0.8 or more, and preferably 1.3 or less, or more. It is preferably 1.2 or less.

Examples of the method for producing the crystalline polyester resin C include, for example, the same examples as the step A for the resin A described above.

(Physical properties of resin C)
The softening point of Resin C is preferably 60° C. or higher, more preferably 70° C. or higher, and still more preferably 80° C. or higher, from the viewpoint of widening the non-offset temperature range, and from the viewpoint of further improving low-temperature fixability. , preferably 150° C. or lower, more preferably 120° C. or lower, and still more preferably 100° C. or lower.

The melting point of Resin C is preferably 50° C. or higher, more preferably 60° C. or higher, and even more preferably 70° C. or higher, from the viewpoint of widening the non-offset temperature range. It is preferably 100° C. or lower, more preferably 90° C. or lower, and still more preferably 80° C. or lower.

The acid value of Resin C is preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, and preferably 35 mgKOH/g or less, more preferably 25 mgKOH/g or less, still more preferably 20 mgKOH/g or less. .

The softening point, melting point, and acid value of Resin C can be appropriately adjusted depending on the type and amount of raw material monomer used, and production conditions such as reaction temperature, reaction time, and cooling rate. determined by the method. When two or more resins C are used in combination, the softening point, melting point, and acid value obtained as a mixture thereof are preferably within the above ranges.

The content of the resin C is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 15% by mass or more, still more preferably 20% by mass or more, relative to the total amount of the resin components of the resin particles X. , more preferably 25% by mass or more, and preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less.

The mass ratio of resin C to resin A in resin particles X [resin C/resin A] is preferably 5/95 or more, more preferably 10/90 or more, and even more preferably 10/90 or more, from the viewpoint of further improving low-temperature fixability. is 15/85 or more, more preferably 20/80 or more, still more preferably 25/75 or more, and preferably 60/40 or less, more preferably 50/50 or less, still more preferably 45/55 or less, and further Preferably it is 40/60 or less.

The total amount of the composite resin A and the crystalline polyester resin C is preferably 70% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more with respect to the total amount of the resin components of the resin particles X. , more preferably 95% by mass or more, and 100% by mass or less, and more preferably 100% by mass.

<<Method for producing resin particles X>>
A dispersion liquid of the resin particles X is obtained by dispersing the resin A in an aqueous medium. The resin C may be dispersed at the same time to form the resin particles X containing the resin A and the resin C, or the resin particles Xa containing the resin A and the resin particles Xb containing the resin C may be used.
The aqueous medium preferably contains water as a main component, and from the viewpoint of improving the dispersion stability of the resin particle dispersion and from the viewpoint of environmental friendliness, the content of water in the aqueous medium is preferably 80 mass. % or more, more preferably 90 mass % or more, still more preferably 95 mass % or more, still more preferably 98 mass % or more, and 100 mass % or less, more preferably 100 mass %. As water, deionized water or distilled water is preferred. Components other than water that can be contained in the aqueous medium include, for example, alkyl alcohols having 1 to 5 carbon atoms; dialkyl ketones having 3 to 5 carbon atoms such as acetone and methyl ethyl ketone; and cyclic ethers such as tetrahydrofuran dissolved in water. and organic solvents.

Dispersion can be carried out using a known method, but it is preferable to disperse by a phase inversion emulsification method. The phase inversion emulsification method includes, for example, a method in which an aqueous medium is added to an organic solvent solution of a resin or a molten resin to effect phase inversion emulsification.

The organic solvent used for phase inversion emulsification is not particularly limited as long as it dissolves the resin, but from the viewpoint of facilitating phase inversion, for example, alcoholic solvents such as ethanol, isopropanol, and isobutanol; acetone, methyl ethyl ketone, and methyl isobutyl ketone. , diethyl ketone and the like; ether solvents such as dibutyl ether, tetrahydrofuran and dioxane; and acetate solvents such as ethyl acetate and isopropyl acetate. Among these, ketone-based solvents and acetic acid ester-based solvents are preferable, and methyl ethyl ketone, ethyl acetate, and isopropyl acetate are more preferable, from the viewpoint of easy removal from the mixed solution after addition of the aqueous medium.
A neutralizing agent is preferably added to the organic solvent solution. Neutralizing agents include, for example, basic substances. Basic substances include, for example, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; and nitrogen-containing basic substances such as ammonia, trimethylamine and diethanolamine.
The use equivalent (mol%) of the neutralizing agent to the acid groups of the resin contained in the resin particles X is preferably 10 mol% or more, more preferably 30 mol% or more, still more preferably 40 mol% or more, and It is preferably 90 mol % or less, more preferably 70 mol % or less.
The equivalent amount (mol%) of the neutralizing agent to be used can be determined by the following formula. The use equivalent of the neutralizing agent is synonymous with the degree of neutralization when it is 100 mol % or less.
Equivalent amount of neutralizing agent used (mol%) = [{added mass of neutralizing agent (g)/equivalent amount of neutralizing agent}/[{weighted average acid value of resin constituting resin particles X (mgKOH/g) x Mass (g) of resin constituting resin particles X}/(56×1000)]]×100

While stirring the organic solvent solution or molten resin, the aqueous medium is gradually added to cause phase inversion.
From the viewpoint of improving the dispersion stability of the resin particles X, the temperature of the organic solvent solution when adding the aqueous medium is preferably at least the glass transition temperature of the resin constituting the resin particles X, preferably at least 50° C., more preferably at least 50° C. 60° C. or higher, and preferably 85° C. or lower, more preferably 80° C. or lower.
The contents of the composite resin A and the crystalline polyester resin C are as described above.

After the phase inversion emulsification, if necessary, the organic solvent may be removed from the resulting dispersion by distillation or the like. In this case, the residual amount of the organic solvent in the dispersion is preferably 1% by mass or less, more preferably 0.5% by mass or less, and even more preferably substantially 0%.

The volume-median particle size (D ₅₀ ) of the resin particles X in the dispersion is preferably 0.05 μm or more, more preferably 0.08 μm or more, from the viewpoint of obtaining a toner capable of obtaining high-quality images, and , preferably 0.8 μm or less, more preferably 0.4 μm or less, and still more preferably 0.3 μm or less.
The CV value of the resin particles X in the dispersion liquid is preferably 10% or more, more preferably 20% or more, and more preferably 40% or less, more preferably from the viewpoint of obtaining a toner capable of obtaining high-quality images. is 35% or less, more preferably 30% or less.
The volume-median particle size ( _D50 ) and CV value of the resin particles are obtained by the methods described in Examples below.

When resin particles Xa containing resin A and resin particles Xb containing resin C are used, resin particles Xa and Xb can be obtained in the same manner as described above.
The amount of the resin particles Xa and the resin particles Xb to be added is preferably the amount corresponding to the content of the resin A and the resin C described above.

〔Release agent〕
In the step (1), together with the resin particles X, release agent particles containing a release agent may be aggregated.
Release agents include, for example, polypropylene wax, polyethylene wax, polypropylene polyethylene copolymer wax; hydrocarbon waxes such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax, and Sasol wax; and oxides thereof; carnauba wax. , montan waxes or their deoxidized waxes, ester waxes such as fatty acid ester waxes; fatty acid amides, fatty acids, higher alcohols, and fatty acid metal salts. These may be used alone or in combination of two or more.

The melting point of the releasing agent is preferably 60° C. or higher, more preferably 70° C. or higher, and preferably 160° C. or lower, more preferably 150° C. or lower, and still more preferably 140° C. or lower.
The content of the release agent in the toner is preferably 0.1% by mass or more, more preferably 1% by mass or more, still more preferably 5% by mass or more, and preferably 20% by mass or less, more preferably It is 15% by mass or less.

(Dispersion of Release Agent Particles)
The release agent is preferably mixed with the resin particles X as a dispersion liquid of release agent particles and aggregated to be contained in the aggregated particles 1 .
Although a dispersion of release agent particles can be obtained using a surfactant, it is preferably obtained by mixing the release agent with resin particles Z described later. By preparing release agent particles using a release agent and resin particles Z, the release agent particles are stabilized by the resin particles Z, and the release agent can be dispersed in an aqueous medium without using a surfactant. Dispersion becomes possible. It is considered that the dispersion liquid of release agent particles has a structure in which a large number of resin particles Z adhere to the surface of the release agent particles.

The resin constituting the resin particles Z in which the release agent is dispersed is preferably a polyester-based resin, and more preferably a composite resin D having a polyester resin segment and an addition polymerized resin segment.

The softening point of composite resin D is preferably 70° C. or higher, more preferably 80° C. or higher, and preferably 140° C. or lower, more preferably 120° C. or lower, and still more preferably 100° C. or lower.

Other suitable ranges of resin properties of Composite Resin D, suitable examples of raw material monomers constituting the resin, and the like are the same as those shown for Composite Resin A. A dispersion of the resin particles Z can be obtained, for example, by the above-described phase inversion emulsification method.
The volume-median particle size (D ₅₀ ) of the resin particles Z is preferably 0.01 μm or more, more preferably 0.03 μm or more, and preferably 0.01 μm or more, from the viewpoint of the dispersion stability of the release agent particles. It is 3 μm or less, more preferably 0.2 μm or less.
From the viewpoint of the dispersion stability of the release agent particles, the CV value of the resin particles Z is preferably 10% or more, more preferably 15% or more, and preferably 40% or less, more preferably 35% or less. More preferably, it is 30% or less.

The release agent particle dispersion is prepared, for example, by dispersing the release agent, the resin particle dispersion, and, if necessary, an aqueous medium at a temperature equal to or higher than the melting point of the release agent using a homogenizer, a high-pressure disperser, an ultrasonic disperser, or the like. Obtained by dispersing using a disperser.
The heating temperature during dispersion is preferably the melting point of the release agent or higher and 80°C or higher, more preferably 85°C or higher, and still more preferably 90°C or higher, and preferably softens the resin contained in the resin particles Z. It is less than 10°C higher than the point and 100°C or less, more preferably 98°C or less, still more preferably 95°C or less.

The amount of resin particles Z is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, still more preferably 20 parts by mass or more, and preferably 100 parts by mass or less with respect to 100 parts by mass of the release agent. , more preferably 70 parts by mass or less, and still more preferably 50 parts by mass or less.

The volume median particle size ( _D50 ) of the release agent particles is preferably 0.05 µm or more, more preferably 0.2 µm or more, and still more preferably 0.4 µm or more, from the viewpoint of obtaining uniform aggregated particles by aggregation. Yes, and preferably 1 μm or less, more preferably 0.8 μm or less, and even more preferably 0.6 μm or less.
The CV value of the release agent particles is preferably 10% or more, more preferably 20% or more, and preferably 40% or less, more preferably 35% or less, still more preferably 30% or less.
The volume-median particle diameter ( _D50 ) and CV value of the release agent particles are measured according to the methods described in Examples.

[Coloring agent]
In the step (1), together with the resin particles X, colorant particles containing a colorant may be aggregated.
As the colorant, all dyes, pigments, etc. used as colorants for toners can be used.
Examples of colorants include carbon black, phthalocyanine blue, permanent brown FG, brilliant first scarlet, pigment green B, rhodamine-B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, and disazo yellow. be done. The toner may be black toner or color toner other than black.

From the viewpoint of improving the image density of the toner, the content of the colorant is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and even more preferably 5 parts by mass with respect to 100 parts by mass of the total resin components in the toner. parts or more, more preferably 8 parts by mass or more, and preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 20 parts by mass or less.

(Dispersion of colorant particles)
It is preferable that the colorant is contained in the aggregated particles 1 by mixing the colorant with the resin particles X as a dispersion liquid of the colorant particles and causing them to aggregate.
The dispersion liquid of the colorant particles is preferably obtained by dispersing the colorant and the aqueous medium using a dispersing machine such as a homogenizer or an ultrasonic dispersing machine. From the viewpoint of improving the dispersion stability of the colorant, the dispersion is preferably carried out in the presence of a surfactant. Examples of the surfactant include nonionic surfactants, anionic surfactants, and cationic surfactants. From the viewpoint of improving the dispersion stability of colorant particles, anionic surfactants are preferred. is an agent. Anionic surfactants include, for example, dodecyl benzene sulfonate, dodecyl sulfate, lauryl ether sulfate, and alkenyl succinate. Among these, dodecylbenzenesulfonate is preferred.

From the viewpoint of improving the dispersion stability of the colorant, the content of the surfactant in the dispersion of the colorant particles is preferably 1 part by mass or more, more preferably 5 parts by mass with respect to 100 parts by mass of the colorant. Above, more preferably 10 parts by mass or more, and preferably 40 parts by mass or less, more preferably 30 parts by mass or less.

The volume median particle diameter ( _D50 ) of the colorant particles is preferably 0.05 μm or more, more preferably 0.08 μm or more, still more preferably 0.1 μm or more, and preferably 0.3 μm or less, more preferably 0.1 μm or more. It is preferably 0.2 μm or less.
The method for measuring the volume-median particle size ( _D50 ) of the colorant particles is according to the method described in Examples.

The aggregated particles 1 may also contain additives such as charge control agents, magnetic powders, fluidity improvers, conductivity modifiers, reinforcing fillers such as fibrous substances, antioxidants, anti-aging agents, and cleaning improvers. may contain.

[Surfactant]
In the step (1), it is preferable to aggregate the resin particles X after preparing the mixed dispersion.
The mixed dispersion may be prepared in the presence of a surfactant from the viewpoint of improving the dispersion stability of optional components such as the resin particles X and release agent particles added as necessary. Examples of surfactants include anionic surfactants such as alkylbenzene sulfonates and alkyl ether sulfates; nonionic surfactants such as polyoxyethylene alkyl ethers and polyoxyethylene alkenyl ethers.
When a surfactant is used, the amount used is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and preferably 10 parts by mass with respect to 100 parts by mass of the resin particles X. parts or less, more preferably 5 parts by mass or less, and even more preferably 3 parts by mass or less.
Mixing of the aforementioned dispersion liquid of resin particles X and arbitrary components is carried out by a conventional method.
Addition conditions of cation (a) and cation (b) are as described above.

The volume-median particle size (D ₅₀ ) of aggregated particles 1 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 8 µm or less, and still more preferably 6 μm or less. The volume-median particle size (D ₅₀ ) of Aggregated Particles 1 is determined by the method described in Examples below.

<Step (2)>
In step (2), resin particles Y containing amorphous polyester resin B are attached to aggregated particles 1 to obtain aggregated particles 2 .
[Resin Particle Y]
The dispersion liquid of the resin particles Y is obtained by the same method as the method for producing the dispersion liquid of the resin particles X described above.
In step (2), for example, by adding a dispersion liquid of resin particles Y to a dispersion liquid containing aggregated particles 1 at 30° C. or higher and 80° C. or lower, resin particles Y are attached to aggregated particles 1 in an aqueous medium. , to obtain agglomerated particles 2.

<<Amorphous polyester resin B>>
Examples of resin B include polyester resins and composite resins containing polyester resin segments and addition polymerized resin segments. Among these, polyester resins, which are polycondensates of alcohol components and carboxylic acid components, are preferred.

When the resin B is a polyester resin, the alcohol component and the carboxylic acid component are the same as the examples of the polyester resin segment in the resin A described above. In the case of a composite resin, examples of the resin B are the same as those of the composite resin of the resin A described above.
Preferred embodiments of the resin B will be described below, omitting common examples.
The alcohol component is preferably an aromatic diol, more preferably an alkylene oxide adduct of bisphenol A, still more preferably an alkylene oxide adduct of bisphenol A represented by formula (I). As the alkylene oxide adduct of bisphenol A, an ethylene oxide adduct of bisphenol A is preferred.
The content of the alkylene oxide adduct of bisphenol A is preferably 70 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol% or less, in the alcohol component, More preferably, it is 100 mol %.

Examples of the method for producing the resin B include the same examples as the step A for the resin A described above.

(Physical properties of resin B)
The softening point of Resin B is preferably 70° C. or higher, more preferably 90° C. or higher, and still more preferably 100° C. or higher. It is 130° C. or lower, more preferably 125° C. or lower.

The glass transition temperature of Resin B is preferably 30° C. or higher, more preferably 40° C. or higher, and still more preferably 50° C. or higher. is 75° C. or less, more preferably 70° C. or less.

The acid value of Resin B is preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, still more preferably 15 mgKOH/g or more, and preferably 40 mgKOH/g or less, more preferably 35 mgKOH/g or less, and further preferably Preferably, it is 30 mgKOH/g or less.
The softening point, glass transition temperature, and acid value of Resin B can be appropriately adjusted depending on the type and amount of raw material monomer used, and production conditions such as reaction temperature, reaction time, and cooling rate. is determined by the method described in Examples.
When two or more resins B are used in combination, the softening point, glass transition temperature and acid value obtained as a mixture thereof are preferably within the ranges described above.

The resin particles Y containing the resin B can be obtained, for example, in the same manner as the resin particles X described above.

The content of the resin B is preferably 60% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, still more preferably 95% by mass or more, relative to the total amount of the resin components of the resin particles Y. and is 100% by mass or less, more preferably 100% by mass.
The mass ratio of resin B to the total amount of resin A and resin C [resin B/total amount of resin A and resin C] is preferably 5/95 or more, more preferably 10/90 or more, and still more preferably 15. /85 or more, and preferably 30/70 or less, more preferably 25/75 or less, and even more preferably 20/80 or less.

The aggregation may be stopped when the aggregated particles have grown to a particle size suitable for toner particles.
Methods for stopping aggregation include, for example, a method of cooling the dispersion, a method of adding an aggregation inhibitor, a method of diluting the dispersion, and a method of changing the pH. From the viewpoint of reliably preventing unnecessary aggregation, a method of stopping aggregation by adding an aggregation terminator is preferred.

[Aggregation terminating agent]
As the aggregation terminator, a surfactant is preferred, and an anionic surfactant is more preferred. Anionic surfactants include, for example, alkylbenzene sulfonates, alkyl sulfates, alkyl ether sulfates, and polyoxyalkylene alkyl ether sulfates. One or more of these aggregation inhibitors may be used. The aggregation terminator may be added in the form of an aqueous solution.
From the viewpoint of reliably preventing unnecessary aggregation, the amount of the aggregation terminator added is preferably 0.1 parts by mass or more, more preferably It is 1 part by mass or more, and preferably 30 parts by mass or less, more preferably 15 parts by mass or less, from the viewpoint of reducing residue in the toner.

The volume-median particle diameter (D ₅₀ ) of the aggregated particles 2 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 8 µm or less, and still more preferably 6 μm or less. The volume-median particle size ( _D50 ) of the aggregated particles is determined by the method described in Examples below.

<Step (3)>
In step (3), the aggregated particles 2 are fused. Note that fusion is usually performed in an aqueous medium.
The fusion temperature is preferably at least the glass transition temperature of the resin A, more preferably at least 5°C higher than the glass transition temperature of the resin A, still more preferably at least 10°C higher than the glass transition temperature of the resin A. preferably 20° C. or higher than the glass transition temperature of resin A, and preferably 50° C. or lower than the glass transition temperature of resin A, more preferably 40° C. or lower than the glass transition temperature of resin A; More preferably, the temperature is 30° C. higher than the glass transition temperature of resin A or less.
It is preferable to monitor the degree of circularity of the fusion-bonded particles, which will be described later, and finish the fusion-bonding when it reaches an appropriate range.

In step (3), an acidic substance may be added for fusing.
[Acidic substance]
Examples of acidic substances include inorganic acids and organic acids.
Inorganic acids include, for example, nitric acid, sulfuric acid, hydrochloric acid, and phosphoric acid.
Examples of organic acids include carboxylic acid compounds such as monocarboxylic acid, dicarboxylic acid and tricarboxylic acid, sulfonic acid compounds such as methanesulfonic acid, benzenesulfonic acid and toluenesulfonic acid, ascorbic acid, phenol, and cresol. Among these, carboxylic acid compounds are preferred.
Carboxylic acid compounds include, for example, acetic acid, lactic acid, tartaric acid, propionic acid, benzoic acid, oxalic acid, terephthalic acid, fumaric acid, succinic acid, acrylic acid, and adipic acid.
Among these, inorganic acids are preferred, and sulfuric acid is more preferred.

The acidic substance is preferably added to the system as an aqueous solution of the acidic substance.
When the acidic substance is added as an aqueous solution, the concentration of the acidic substance in the aqueous solution of the acidic substance is preferably 0.01 mol/L or more, more preferably 0.03 mol/L or more, and still more preferably 0.05 mol/L or more. Yes, and preferably 1 mol/L or less, more preferably 0.8 mol/L or less, still more preferably 0.5 mol/L or less.

The method of adding the acidic substance may be any of a method of adding all at once, a method of adding the total amount in two or more portions, and a method of continuously adding over a certain period of time. From the viewpoint of suppressing further agglomeration of particles, it is preferable to use either a method of dividing addition or a method of continuously adding over a certain period of time. The temperature at which the acidic substance is added is preferably within the aforementioned fusion temperature range.

The volume median particle size ( _D50 ) of the fused particles obtained by fusion 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 μm or less, more preferably 6 μm or less.
The circularity of the fused particles is preferably 0.945 or more, more preferably 0.950 or more, still more preferably 0.955 or more, and preferably 0.990 or less, more preferably 0.980 or less, More preferably, it is 0.975 or less.
The degree of circularity of the fused particles is according to the method described in Examples.

<Post-treatment process>
A post-treatment step may be performed after step (3) to obtain toner particles by isolating the fusing particles. Since the fused particles obtained in the step (3) are present in the aqueous medium, it is preferable to perform solid-liquid separation first. Solid-liquid separation includes, for example, a suction filtration method, a pressure filtration method, and a centrifugal filtration method, and the suction filtration method is preferably used.
Washing is preferably performed after solid-liquid separation. At this time, since it is preferable to remove the added surfactant as well, it is preferable to wash with an aqueous medium at a temperature not higher than the cloud point of the surfactant. Washing is preferably performed multiple times.
Drying is then preferably carried out. Drying methods include, for example, vacuum low-temperature drying, vibratory fluidized drying, spray drying, freeze drying, and flash drying.

[Toner particles]
The toner particles can be used as the toner as they are, but it is preferable to use the toner after the surface of the toner particles has been treated as described later.
The volume-median particle diameter ( _D50 ) of the toner particles is preferably 2 μm or more, more preferably 3 μm or more, and still more preferably 4 μm or more, from the viewpoint of obtaining high-quality images and further improving the cleanability of the toner. Yes, and preferably 10 μm or less, more preferably 8 μm or less, and even more preferably 6 μm or less.
The volume-median particle size ( _D50 ) of toner particles can be measured by the method described in Examples.

The content of the toner particles in the toner is preferably 60% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, still more preferably 95% by mass or more, and 100% by mass or less. Yes, preferably 99% by mass or less.

[External additive]
Although the toner particles can be used as the toner as it is, it is preferable to use the toner after adding a fluidizing agent or the like as an external additive to the surface of the toner particles.
Examples of external additives include inorganic material fine particles such as hydrophobic silica, titanium oxide, alumina, cerium oxide, and carbon black, and polymer fine particles such as polycarbonate, polymethyl methacrylate, and silicone resin. Among these, hydrophobic silica is preferred.
When the toner particles are surface-treated using an external additive, the amount of the external additive added is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and still more preferably 100 parts by mass of the toner particles. It is 3 parts by mass or more, and preferably 5 parts by mass or less, more preferably 4.5 parts by mass or less, and even more preferably 4 parts by mass or less.

The electrostatic charge image developing toner obtained by the present invention can be used as a one-component developer, or can be mixed with a carrier and used as a two-component developer.

EXAMPLES The present invention will be described in more detail with reference to Examples and the like below. In the following examples, etc., the physical properties were measured and evaluated by the following methods. In the following examples, room temperature means a temperature of 20.degree. C. to 25.degree.

[Measuring method]
[Acid value of resin]
The acid value of the resin was measured according to JIS K0070:1992. However, a mixed solvent of acetone and toluene [acetone:toluene=1:1 (volume ratio)] was used as the measurement solvent.

[Resin softening point, crystallinity index, melting point and glass transition temperature]
(1) Softening point Using a flow tester "CFT-500D" (manufactured by Shimadzu Corporation), while heating a 1 g sample at a temperature increase rate of 6 ° C./min, a load of 1.96 MPa is applied with a plunger, and the diameter It was extruded through a 1 mm, 1 mm long nozzle. The amount of plunger depression of the flow tester was plotted against the temperature, and the softening point was defined as the temperature at which half of the sample flowed out.
(2) Crystallinity index Using a differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), 0.01 g of the sample was weighed into an aluminum pan and cooled to 0 ° C. at a cooling rate of 10 ° C./min. cooled to Next, the sample was allowed to stand still for 1 minute, then heated to 180°C at a heating rate of 10°C/min, and the calorific value was measured. Among the observed endothermic peaks, the temperature of the peak with the maximum peak area is defined as the maximum endothermic peak temperature (1), and (softening point (°C)) / (maximum endothermic peak temperature (1) (°C)) A crystallinity index was determined.
(3) Melting point and glass transition temperature Using a differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), 0.01 g of the sample was weighed into an aluminum pan, heated to 200 ° C., It was cooled from that temperature to 0°C at a cooling rate of 10°C/min. After that, the temperature was raised at a rate of temperature rise of 10° C./min, and the calorie was measured. Among the observed endothermic peaks, the peak temperature with the maximum peak area was taken as the maximum endothermic peak temperature (2). In the case of a crystalline resin, the peak temperature was taken as the melting point. In the case of an amorphous resin, the glass transition temperature was defined as the temperature at the intersection of the extended line of the baseline below the maximum endothermic peak temperature and the tangent line showing the maximum slope from the rising portion of the peak to the apex of the peak.

[Melting point of release agent]
Using a differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), 0.01 g of the sample was weighed into an aluminum pan, heated to 200 ° C., and then cooled at a rate of 10 ° C. from 200 ° C. /min to 0°C. Next, the temperature of the sample was increased at a temperature increase rate of 10° C./min, the calorie was measured, and the maximum endothermic peak temperature was defined as the melting point.

[Volume Median Particle Diameter (D ₅₀ ) and CV Value of Resin Particles, Release Agent Particles, and Colorant Particles]
(1) Measuring device: Laser diffraction particle size measuring machine “LA-920” (manufactured by HORIBA, Ltd.)
(2) Measurement conditions: A sample dispersion was placed in a measurement cell, distilled water was added, and the volume-median particle size (D ₅₀ ) and volume-average particle size were measured at a temperature at which the absorbance was within the appropriate range. Also, the CV value was calculated according to the following formula.
CV value (%) = (standard deviation of particle size distribution/volume average particle size) x 100

[Solid Content Concentration of Resin Particle Dispersion, Release Agent Particle Dispersion, and Colorant Particle Dispersion]
Using an infrared moisture meter "FD-230" (manufactured by Ketsuto Kagaku Kenkyusho Co., Ltd.), 5 g of the measurement sample is dried at a temperature of 150 ° C., under the conditions of measurement mode 96 (monitoring time 2.5 minutes, fluctuation width 0.05%). , and the water content (% by mass) of the dispersion was measured. The solid content concentration was calculated according to the following formula.
Solid content concentration (mass%) = 100 - moisture (mass%)

[Volume-median particle diameter (D ₅₀ ) of aggregated particles]
The volume-median particle size ( _D50 ) of aggregated particles was measured as follows.
・Measuring machine: “Coulter Multisizer (registered trademark) III” (manufactured by Beckman Coulter, Inc.)
・Aperture diameter: 50 μm
・ Analysis software: “Multisizer (registered trademark) III version 3.51” (manufactured by Beckman Coulter, Inc.)
・ Electrolyte: “Isoton (registered trademark) II” (manufactured by Beckman Coulter, Inc.)
Measurement conditions: By adding the sample dispersion to 100 mL of the electrolytic 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 again, and the particle size The volume median particle size ( _D50 ) was determined from the distribution.

[Circularity of Toner Particles (Fusing Particles)]
The circularity of toner particles (fused particles) was measured under the following conditions.
・ Measuring device: Flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation)
Preparation of dispersion liquid: A dispersion liquid of toner particles was diluted with deionized water so as to have a solid content concentration of 0.001 to 0.05% by mass.
・Measurement mode: HPF measurement mode

[Volume Median Particle Diameter ( _D50 ) and CV Value of Toner Particles]
The volume median particle size ( _D50 ) of the toner particles was measured as follows.
The measuring device, aperture diameter, analysis software, and electrolytic solution used were the same as those used in the measurement of the volume-median particle diameter (D ₅₀ ) of the aggregated particles described above.
- Dispersion: Polyoxyethylene lauryl ether "Emulgen (registered trademark) 109P" (manufactured by Kao Corporation, HLB (Hydrophile-Lipophile Balance) = 13.6) is dissolved in the electrolytic solution to obtain a dispersion with a concentration of 5% by mass. got
Dispersion conditions: 10 mg of a measurement sample of dried toner particles is added to 5 mL of the dispersion liquid, dispersed for 1 minute with an ultrasonic disperser, and then 25 mL of an electrolytic solution is added, followed by an ultrasonic disperser. Disperse for 1 minute to prepare a sample dispersion.
Measurement conditions: By adding the sample dispersion to 100 mL of the electrolytic 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 ( _D50 ) and volume-average particle size were obtained from the distribution.
Also, the CV value (%) was calculated according to the following formula.
CV value (%) = (standard deviation of particle size distribution/volume average particle size) x 100

[Evaluation method]
[Low Temperature Fixability of Toner]
Using a commercially available printer "Microline (registered trademark) 5400" (manufactured by Oki Data Co., Ltd.) on high-quality paper "J paper A4 size" (manufactured by Fuji Xerox Co., Ltd.), the toner adhesion amount on the paper is 1.49 to 1. A solid image of 0.51 mg/cm ² was output on A4 paper with a length of 50 mm, leaving a margin of 5 mm from the top edge, without being fixed. Next, the same printer with a variable temperature fixing device was prepared, the temperature of the fixing device was set to 100° C., and the toner was fixed at a speed of 1.3 seconds per sheet of A4 paper in the longitudinal direction to obtain printed matter.
By the same method, the temperature of the fixing device was increased by 5° C. to fix the toner, and a printed matter was obtained.
A piece of mending tape "Scotch (registered trademark) Mending Tape 810" (manufactured by Sumitomo 3M Co., Ltd., width 18 mm) cut into a length of 50 mm is lightly pasted from the top margin of the printed image to the solid image. After that, a weight of 500 g (contact area: 1963 mm ² ) was placed and pressed once at a speed of 10 mm/s. After that, the attached tape was peeled off from the lower end side at a peeling angle of 180° and a speed of 10 mm/s to obtain a print after tape peeling. Thirty sheets of high-quality paper "Excellent White Paper A4 size" (manufactured by Oki Data Co., Ltd.) were placed under the printed matter before and after the tape was applied, and the reflected image density of the fixed image portion of each printed matter was measured before and after the tape was applied. , SpectroEye colorimeter (manufactured by GretagMacbeth, light irradiation conditions; standard light source D50, observation field of view 2°, density standard DINNB, absolute white standard). was calculated.
Fixing rate (%) = (reflected image density after tape removal/reflected image density before tape application) x 100
The lowest temperature at which the fixing rate was 90% or higher was defined as the lowest fixing temperature. The lower the minimum fixing temperature in this test, the better the low-temperature fixability.

[Non-offset temperature range of toner]
The temperature of the fixing device was raised to 200° C. by 5° C. in the same manner as in the low temperature fixability evaluation, and the toner was fixed to obtain a printed matter. The image of the printed matter was visually checked to confirm the temperature at which high-temperature offset occurred, and a temperature 5° C. lower than that temperature was defined as the maximum non-offset temperature. The non-offset temperature width of the toner was calculated according to the following formula.
Non-offset temperature range (°C) = (maximum non-offset temperature) - (minimum fixing temperature)

[Resin production]
Production Example A1 (Production of Amorphous Resin A-1)
The inside of a four-necked flask with an internal volume of 10 L equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 4200 g of propylene oxide (2.2) adduct of bisphenol A, 1355 g of terephthalic acid, di 31 g of (2-ethylhexanoic acid) tin (II) and 3 g of gallic acid (3,4,5-trihydroxybenzoic acid) were added, and the temperature was raised to 235°C under a nitrogen atmosphere while stirring. After holding for 5 hours, the pressure in the flask was lowered and held at 8 kPa for 1 hour. After returning to atmospheric pressure, the system was cooled to 160°C, and a mixture of 1819 g of styrene, 455 g of stearyl methacrylate, 138 g of acrylic acid, and 227 g of dibutyl peroxide was added dropwise over 1 hour while maintaining the temperature at 160°C. Then, after holding at 160° C. for 30 minutes, the temperature was raised to 200° C., the pressure in the flask was further lowered, and the pressure was held at 8 kPa for 1 hour. After returning to atmospheric pressure, the mixture was cooled to 190°C, 223 g of fumaric acid, 230 g of trimellitic anhydride, and 2.5 g of 4-tert-butylcatechol were added, and the temperature was raised to 210°C at a rate of 10°C/hr. After that, reaction was carried out at 4 kPa to a desired softening point to obtain an amorphous resin A-1. Various physical properties of the resin were measured and shown in Table 1.

Production Example B1 (Production of Amorphous Resin B-1)
The inside of a four-neck flask with an internal volume of 10 L equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 5363 g of ethylene oxide (2.2) adduct of bisphenol A, 1780 g of terephthalic acid, di 40 g of (2-ethylhexanoic acid) tin (II) and 4 g of gallic acid are added, heated to 235°C under a nitrogen atmosphere with stirring, maintained at 235°C for 8 hours, and then the pressure in the flask is reduced. , and held at 8 kPa for 1 hour. Then, after returning to atmospheric pressure, cool to 180°C, add 287 g of fumaric acid, 221 g of dodecenylsuccinic anhydride, 380 g of trimellitic anhydride, and 2.5 g of 4-tert-butylcatechol, and heat to 220°C by 10°C. /hr, the pressure in the flask was then lowered, and the reaction was carried out at 10 kPa to a desired softening point to obtain an amorphous resin B-1. Various physical properties of the resin were measured and shown in Table 1.

Production Example D1 (Production of Amorphous Resin D-1)
The inside of a 10 L four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was purged with nitrogen, and 4313 g of a propylene oxide (2.2) adduct of bisphenol A, 818 g of terephthalic acid, and succinic acid were added. 727 g of acid, 30 g of di(2-ethylhexanoic acid) tin (II), and 3 g of gallic acid were added, heated to 235° C. with stirring under a nitrogen atmosphere, and maintained at 235° C. for 5 hours. was lowered and held at 8 kPa for 1 hour. After returning to atmospheric pressure, the system was cooled to 160°C, and a mixture of 2755 g of styrene, 689 g of stearyl methacrylate, 142 g of acrylic acid, and 413 g of dibutyl peroxide was added dropwise over 1 hour while the temperature was maintained at 160°C. Then, after holding at 160° C. for 30 minutes, the temperature was raised to 200° C., the pressure in the flask was further lowered, and the reaction was carried out to the desired softening point at 8 kPa to obtain amorphous resin D-1. Various physical properties of the resin were measured and shown in Table 1.

Production Example C1 (Production of crystalline polyester resin C-1)
The inside of a 10 L four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer and a thermocouple was replaced with nitrogen, and 3416 g of 1,10-decanediol and 4084 g of sebacic acid were placed therein. The temperature was raised to 135° C. with stirring, held at 135° C. for 3 hours, and then raised from 135° C. to 200° C. over 10 hours. After that, 23 g of di(2-ethylhexanoic acid) tin (II) was added, and the temperature was maintained at 200°C for 1 hour. C-1 was obtained. Various physical properties of the resin were measured and shown in Table 2.

[Production of resin particle dispersion]
Production Example X1 (Production of Resin Particle Dispersion X-1)
210 g of amorphous resin A-1 was added to a container having an internal volume of 3 L equipped with a stirrer "Three One Motor BL300" (manufactured by Shinto Scientific Co., Ltd.), a reflux condenser, a dropping funnel, a thermometer and a nitrogen inlet tube. 90 g of the flexible polyester resin C-1 and 300 g of methyl ethyl ketone were added, and the resins were dissolved at 73° C. for 2 hours. A 5% by mass sodium hydroxide aqueous solution was added to the resulting solution so that the degree of neutralization would be 60 mol % with respect to the acid value of the resin, and the mixture was stirred for 60 minutes.
Then, while maintaining the temperature at 73° C. and stirring at 200 r/min (peripheral speed of 63 m/min), 600 g of deionized water was added over 60 minutes for phase inversion emulsification. While the temperature was maintained at 73° C., methyl ethyl ketone was distilled off under reduced pressure to obtain an aqueous dispersion. Then, after cooling the aqueous dispersion to 30° C. while stirring, deionized water was added to adjust the solid content concentration to 30% by mass, and then filtered through a 150-mesh wire mesh. -1 was obtained. Table 3 shows the volume-median particle size ( _D50 ) and CV value of the obtained resin particles.

Production Examples Y1 and Z1 (Production of Resin Particle Dispersions Y-1 and Z-1)
Resin particle dispersions Y-1 and Z-1 were obtained in the same manner as in Production Example X1, except that the combinations of the amorphous resin and the crystalline polyester resin used were as shown in Table 3. Table 3 shows the volume-median particle size ( _D50 ) and CV value of the obtained resin particles.

[Production of Release Agent Particle Dispersion]
Production Example W1 (Production of Release Agent Particle Dispersion W-1)
120 g of deionized water, 53 g of resin particle dispersion Z-1, and 40 g of paraffin wax "HNP-9" (manufactured by Nippon Seiro Co., Ltd., melting point 75 ° C.) were added to a beaker with an internal volume of 1 L, and the temperature was increased to 90 to 95 ° C. The temperature was maintained to melt and stir to obtain a molten mixture. While maintaining the temperature at 90 to 95° C., dispersion treatment was performed for 20 minutes using an ultrasonic homogenizer “US-600T” (manufactured by Nippon Seiki Seisakusho Co., Ltd.), and then cooled to room temperature. Deionized water was added to the resulting dispersion to adjust the solid content concentration to 20% by mass to obtain release agent particle dispersion W-1. The volume median particle size ( _D50 ) was 0.45 μm and the CV value was 26%.

[Production of colorant particle dispersion]
Production Example P1 (Production of Colorant Particle Dispersion P-1)
In a beaker with an internal volume of 1 L, copper phthalocyanine pigment "ECB-301" (manufactured by Dainichiseika Kogyo Co., Ltd.) 136.0 g, anionic surfactant "Neoperex (registered trademark) G-15" (manufactured by Kao Corporation, 15% by mass sodium dodecylbenzenesulfonate aqueous solution) 181.3 g and deionized water 340 g were mixed and dispersed at room temperature for 3 hours using a homogenizer, and then deionized water was added so that the solid content concentration was 24% by mass. Colorant particle dispersion liquid P-1 was obtained by the addition. The volume median particle size ( _D50 ) of the colorant particles in the dispersion was 0.12 μm.

[Toner production]
Example 1 (Preparation of Toner 1)
300 g of resin particle dispersion X-1, 50.6 g of release agent particle dispersion W-1, and a colorant particle dispersion were placed in a four-necked flask with an internal volume of 2 L equipped with a dehydration tube, a stirrer, and a thermocouple. 33.8 g of P-1, nonionic surfactant "Emulgen (registered trademark) 150" (manufactured by Kao Corporation, polyoxyethylene (average number of moles added: 50) lauryl ether) 10% by weight aqueous solution 9 g, anionic Surfactant "Neopelex G-15" (manufactured by Kao Corporation, sodium dodecylbenzenesulfonate, effective concentration 15% by mass) 6 g (3 mmol as sodium ion per 100 g of resin in the system), 150% deionized water .0 g was mixed at a temperature of 25°C. Next, while stirring the mixture, 31.0 g of ammonium sulfate (420 mmol as ammonium ions per 100 g of resin in the system) was dissolved in 449 g of deionized water, and 22.8 wt. A solution adjusted to pH 8.4 by adding 4 g (17 mmol as potassium ion per 100 g of resin in the system) was added dropwise at 25° C. over 15 minutes. Next, 10.8 g of a 10% by mass aluminum sulfate aqueous solution (5.7 mmol as aluminum ions per 100 g of resin in the system) was added dropwise at 25° C. over 3 minutes. Thereafter, the temperature was raised to 62° C. over 2 hours and maintained at 62° C. until the volume median particle diameter (D ₅₀ ) of the aggregated particles reached 5.1 μm, thereby obtaining an aggregated particle dispersion.
The aggregated particle dispersion was cooled to 55° C., and while maintaining the temperature at 55° C., a mixture of 60.0 g of resin particle dispersion Y-1 and 18.3 g of deionized water was added over 120 minutes, and the resin was added to the aggregated particles. An aggregated particle dispersion liquid in which particles were aggregated was obtained.
In the aggregated particle dispersion, 17.4 g of an anionic surfactant "Emal (registered trademark) E-27C" (manufactured by Kao Corporation, sodium polyoxyethylene lauryl ether sulfate, effective concentration 27% by mass), 590% deionized water An aqueous solution mixed with .1 g was added. After that, the temperature was raised to 75° C. over 1 hour. After reaching 75° C., 98.0 g of 0.1 mol/L sulfuric acid aqueous solution was added. The circularity is measured while maintaining the temperature at 75° C., and the temperature is maintained at 75° C. until the circularity reaches the range of 0.965 to 0.975 to obtain a dispersion of fused particles in which aggregated particles are fused. rice field.
The resulting fused particle dispersion is cooled to 30° C., filtered by suction to separate the solid content, washed with deionized water at 25° C., and vacuum-dried at 35° C. for 48 hours to obtain a toner. Particles were obtained. 100 parts by mass of the toner particles, 2.5 parts by mass of hydrophobic silica “RY50” (manufactured by Nippon Aerosil Co., Ltd., number average particle diameter: 0.04 μm), and hydrophobic silica “Cabosil (registered trademark) TS720” (Cabot Japan) Co., Ltd., number average particle size; The obtained toner was evaluated, and the results are shown in Table 4.

Example 2 (Preparation of Toner 2)
In Example 1, 10.8 g of 10% by mass aluminum sulfate aqueous solution was changed to 10.8 g of 10% by mass iron (III) chloride aqueous solution (6.0 mmol as iron (III) ions per 100 g of resin in the system). Toner 2 was obtained in the same manner except that The obtained toner was evaluated, and the results are shown in Table 4.

Example 3 (Preparation of Toner 3)
In the same manner as in Example 1, except that 10.8 g of 10% by mass aluminum sulfate aqueous solution was changed to 10.8 g of 10% by mass magnesium sulfate aqueous solution (8.1 mmol as magnesium ion per 100 g of resin in the system). Toner 3 was obtained. The obtained toner was evaluated, and the results are shown in Table 4.

Example 4 (Preparation of Toner 4)
Toner 4 was obtained in the same manner as in Example 1, except that 10.8 g of the 10% by mass aluminum sulfate aqueous solution was changed to 6.5 g (3.4 mmol as aluminum ions per 100 g of the resin in the system). The obtained toner was evaluated, and the results are shown in Table 4.

Example 5 (Preparation of Toner 5)
Toner 5 was obtained in the same manner as in Example 1, except that 10.8 g of the 10 mass % aluminum sulfate aqueous solution was changed to 19.4 g (10.2 mmol as aluminum ions per 100 g of the resin in the system). The obtained toner was evaluated, and the results are shown in Table 4.

Example 6 (Preparation of Toner 6)
Toner 6 was obtained in the same manner as in Example 1, except that 10.8 g of the 10 mass % aluminum sulfate aqueous solution was changed to 27.0 g (14.2 mmol as aluminum ions per 100 g of the resin in the system). The obtained toner was evaluated, and the results are shown in Table 4.

Comparative Example 1 (Preparation of Toner 81)
Toner was prepared in the same manner as in Example 1, except that 10.8 g of a 10% by mass aluminum sulfate aqueous solution was changed to 10.8 g of a 10% by mass ammonium sulfate aqueous solution (14.7 mmol as ammonium ions per 100 g of the resin in the system). 81 was obtained. The obtained toner was evaluated, and the results are shown in Table 4.

Comparative Example 2 (Preparation of Toner 82)
In Example 1, 10.8 g of 10% by mass aluminum sulfate aqueous solution was changed to 16.2 g of 10% by mass potassium chloride aqueous solution (19.5 mmol as potassium ion per 100 g of resin in the system) in the same manner. Toner 82 was obtained. The obtained toner was evaluated, and the results are shown in Table 4.

Comparative Example 3 (Preparation of Toner 83)
Toner 83 was obtained in the same manner as in Example 1, except that 10.8 g of the 10% by mass aluminum sulfate aqueous solution was not added. The obtained toner was evaluated, and the results are shown in Table 4.

Comparative Example 4 (Preparation of Toner 84)
Toner 84 was obtained in the same manner as in Example 1, except that 10.8 g of the 10 mass % aluminum sulfate aqueous solution was changed to 2.2 g (1.2 mmol as aluminum ions per 100 g of the resin in the system). The obtained toner was evaluated, and the results are shown in Table 4.

From the results of Examples and Comparative Examples, it can be seen that the present invention can provide a toner that exhibits excellent low-temperature fixability and a wide non-offset temperature range.

Claims (5)

a first aggregation step of aggregating resin particles X containing an amorphous polyester resin A in an aqueous medium to obtain aggregated particles;
A fusing step of fusing the obtained aggregated particles,
In the first aggregation step, adding a monovalent cation (a) and a divalent or higher metal cation (b),
The amount of the cation (b) added is 0.5 mol% or more and 5 mol% or less with respect to the total amount of the cation (a) and the cation (b) ,
The valence B of the cation (b), the added mole number C of the cation (b), and the mole number A of the carboxyl group in the entire polyester resin in the system have the relationship of the following formula (1). ,
0.2 < (B x C)/A < 1 (1)
A method for producing a toner for electrostatic charge image development. After the first aggregation step, the resin particles X are aggregated in an aqueous medium, and then the resin particles Y containing the amorphous polyester-based resin B are further adhered to the aggregated particles to obtain aggregated particles in a second aggregation step. 2. The method for producing a toner for developing an electrostatic charge image according to claim 1 , further comprising: 3. The method for producing a toner for electrostatic charge image development according to claim 1, wherein a salt containing cation (a) and a salt containing cation (b) are added in the first aggregation step. 4. The method for producing a toner for electrostatic charge image development according to claim 3 , wherein the salt containing the cation (a) is an ammonium sulfate salt. 5. The method for producing a toner for electrostatic charge image development according to claim 3 , wherein the salt containing the cation ( b) is at least one selected from aluminum sulfate, iron(III) chloride, and magnesium sulfate.