JP2022169300A - Electrostatic charge image development toner - Google Patents

Abstract

To provide an electrostatic charge image development toner that causes less covering and can maintain a high stability of the concentration of an image even in a continuous printing with less toner consumption.SOLUTION: In an electrostatic charge image development toner, small-diameter silica particles with particles of 10 nm to 30 nm, both inclusive, converted from a specific surface area and large-diameter silica particles with particles of 70 nm to 190 nm, both inclusive, converted from a specific surface area are added to toner mother particles with a circularity of at least 0.965, and the mass ratio of the amount of the added large-particle silica particles to the added small-particle silica particles is in the range of 7 to 18, both inclusive.SELECTED DRAWING: None

Description

The present invention relates to a toner for electrostatic charge image development.

2. Description of the Related Art In image forming apparatuses such as electrophotographic apparatuses, electrostatic recording apparatuses, and electrostatic printing apparatuses, a desired image is formed by developing an electrostatic latent image formed on a photoreceptor with an electrostatic image developing toner. technology is widely used. Such techniques are applied to copiers, printers, facsimiles, multi-function machines of these machines, and the like.
In recent years, amidst the demand for image formation with higher definition and higher image quality, toners for electrostatic charge image development using toner base particles having a high degree of circularity have been used.
Patent Document 1 discloses a toner having a core-shell structure for the purpose of providing a toner capable of exhibiting excellent polishing performance and improving cleaning performance. It describes a toner characterized by containing abrasive fine particles having an average particle diameter of 0.1 to 1.0 μm in a proportion of 0.3 to 3.0 parts by weight per part.
Further, in Patent Document 2, filming on a photoreceptor is unlikely to occur, the toner particles are imparted with a stable charging property over time, and deterioration of image quality due to fog etc. is unlikely to occur even when a large number of sheets are continuously printed. For the purpose of providing an electrostatic charge image developing toner which is resistant to deterioration of image quality even in a high-temperature and high-humidity environment, fatty acid zinc having a number average primary particle diameter of 0.5 to 1.5 μm is used as an external additive. A toner for electrostatic charge image development containing specific amounts of particles, silica fine particles (A) having a solid average primary particle size of 5 to 20 nm, and silica fine particles (B) having a number average primary particle size of 25 to 80 nm. ing.

JP 2007-187988 A JP 2011-203666 A

The electrostatic charge image developing toners described in Patent Documents 1 and 2 have a problem that the uniformity of the toner charge amount is not sufficient and the occurrence of fogging cannot be sufficiently suppressed. In addition, no consideration has been given to optimizing the toner conveying amount.
TECHNICAL FIELD The present invention relates to a toner for developing an electrostatic charge image that suppresses the occurrence of fogging even in continuous printing with a small amount of toner consumption and has high image density stability.

The inventors of the present invention externally add small-diameter silica particles having a specific particle size and large-diameter silica particles in a specific amount ratio to toner base particles having a high degree of circularity, thereby achieving the above-described I have found that the problem is solved.

That is, the present invention relates to the following [1].
[1] To toner base particles having a circularity of 0.965 or more,
Small-diameter silica particles having a particle size of 10 nm or more and 30 nm or less calculated from the specific surface area;
Large silica particles having a particle size of 70 nm or more and 190 nm or less converted from the specific surface area are externally added,
The mass ratio of the added amount of the large particle size silica particles and the small particle size silica particles (large particle size silica particles/small particle size silica particles) is 7 or more and 18 or less.
Toner for electrostatic charge image development.

According to the present invention, it is possible to provide an electrostatic charge image developing toner that suppresses the occurrence of fogging even in continuous printing with a small amount of toner consumption and has high image density stability.

[Electrostatic charge image developing toner]
The toner for electrostatic charge image development of the present invention (hereinafter also simply referred to as "toner") comprises toner base particles having a circularity of 0.965 or more and a small particle size of 10 nm or more and 30 nm or less when converted from the specific surface area. Particle size silica particles and large size silica particles with a size of 70 nm or more and 190 nm or less calculated from the specific surface area are externally added, and the mass ratio of the amount of addition of the large size silica particles and the small size silica particles ( large-diameter silica particles/small-diameter silica particles) is 7 or more and 18 or less.
In the following description, the toner for electrostatic charge image development contains toner base particles and an external additive, and preferably consists of toner base particles and an external additive. Individual particles of the toner for electrostatic charge image development are also referred to as "toner particles".

In the non-magnetic one-component development method, the toner conveyed from the developing roller is required to be instantaneously and uniformly triboelectrically charged when passing through the developing blade. Since the friction between the developing blade and the toner particles is reduced, uniform triboelectrification becomes difficult, resulting in the problem that fogging tends to occur. In addition, since the friction between the developing roller and the toner particles is also reduced, the toner is less likely to be caught on the developing roller, making it impossible to ensure a stable transport amount, which also poses a problem that the image density cannot be ensured.
According to the present invention, there is provided an electrostatic charge image developing toner that suppresses fogging even in continuous printing with a small amount of toner consumption and has high image density stability.
Although the reason why the above effect is obtained is not clear, it is considered as follows.
Small particle size silica having a particle size of 10 nm or more and 30 nm or less calculated from the specific surface area and large particle size silica having a particle size of 70 nm or more and 190 nm or less calculated from the specific surface area are added as external additives at a specific addition amount ratio. By combining the two, the external additive creates fine surface irregularities on the surface of the toner, which improves the triboelectrification effect acting between the developing blade and the toner particles, improving the charging uniformity of the toner and suppressing fogging. It is thought that
On the other hand, if the friction acting between the developing blade and the toner particles is increased, the friction acting between the developing roller and the toner particles also increases, so the amount of toner transported on the developing roller increases. If the friction acting between the developing roller and the toner particles increases excessively, the toner tends to leak from the gap between the developing roller and the developing blade. Since the frictional force acting between the developing roller and the toner particles does not increase more than necessary, it is presumed that the amount of toner transported is optimized and the occurrence of toner leakage is suppressed.
It should be noted that the above mechanism regarding the effect of the present invention is an assumption, and is not limited to this.

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 in which no endothermic peak is observed or, if observed, the crystallinity index is 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 obtained by dividing the sum of the values obtained by multiplying the particle size by the volume of all the particles measured by the total volume of the particles measured. diameter.
CV value (%) = [standard deviation of particle size distribution (μm)/volume average particle size (μm)] × 100

<Toner base particles>
In the present invention, the circularity of the toner base particles is 0.965 or more. A high-definition image can be obtained when the degree of circularity is 0.965 or more.
The circularity of the toner base particles is 0.965 or more, preferably 0.968 or more, more preferably 0.970 or more, from the viewpoint of obtaining high-definition images, and further suppresses the occurrence of fogging. From the viewpoint, it is preferably 0.995 or less, more preferably 0.990 or less, still more preferably 0.985 or less, and even more preferably 0.980 or less.
The circularity of the toner base particles is measured by the method described in Examples.

The toner base particles preferably contain a binder resin and, in addition to the binder resin, contain a colorant and a release agent.
The toner base particles may be toner base particles obtained by any known method such as a melt kneading method, an emulsification phase inversion method, a polymerization method, and an aggregation fusion method, but from the viewpoint of obtaining a desired degree of circularity. The toner base particles are preferably obtained by the aggregation and fusion bonding method, and more preferably toner base particles having a core-shell structure.
Preferred embodiments of the toner base particles will be described below, but in the present invention, the toner base particles are not particularly limited as long as they have the above circularity.

[Binder resin]
The toner base particles preferably contain a polyester-based resin, more preferably an amorphous polyester-based resin A, as a binder resin from the viewpoint of excellent low-temperature fixability and obtaining a desired degree of circularity. More preferably, the amorphous polyester resin A and the crystalline polyester resin C are contained.

<<Amorphous polyester resin A>>
In the present invention, the toner base particles preferably contain the amorphous polyester resin A as the binder resin, and more preferably contain the amorphous polyester resin A in the core portion.
The amorphous polyester-based resin A is, for example, an amorphous polyester-based resin containing a polycondensate of an alcohol component and a carboxylic acid component.
Examples of amorphous polyester resins include polyester resins and modified polyester resins. Modified polyester resins include, for example, urethane-modified polyester resins, epoxy-modified polyester resins, and composite resins containing polyester resin segments and addition polymerized resin segments. Among these, it is an amorphous composite resin containing a polyester resin segment that is a polycondensate of an alcohol component and a carboxylic acid component and an addition polymerized resin segment that is an addition polymer of a raw material monomer containing a styrene compound. is preferred.

Examples of the alcohol component include alkylene oxide adducts of aromatic diols, linear or branched aliphatic diols, alicyclic diols, and trihydric or higher polyhydric alcohols. Among these, alkylene oxide adducts of aromatic diols are preferable from the viewpoint of obtaining a toner excellent in low-temperature fixability.
The alkylene oxide adduct of an aromatic diol is preferably an alkylene oxide adduct of bisphenol A, more preferably of formula (I):

（式中、ＯＲ^１及びＲ^２Ｏはオキシアルキレン基であり、Ｒ^１及びＲ^２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はアルキレンオキシドの平均付加ｍｏｌ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１６以下である）で表されるビスフェノールＡのアルキレンオキシド付加物である。

(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 and 16 or less).

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 use 1 type(s) or 2 or more types. 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, more preferably 100 mol%, in the alcohol component. %.

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.
Alicyclic diols include, for example, hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane], alkylene oxide adducts having 2 to 4 carbon atoms of hydrogenated bisphenol A (average addition mol number 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 preferable.
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 90 mol% or less, It is 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, and fumaric acid and sebacic acid are more preferred.
The amount of linear or branched aliphatic dicarboxylic acid is preferably 1 mol% or more, more preferably 3 mol% or more, still more preferably 10 mol% or more, and preferably 80 mol% or less, more preferably 80 mol% or less, in the carboxylic acid component. is 50 mol % or less, 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% or more in the carboxylic acid component. , and preferably 30 mol % or less, more preferably 25 mol % or less, and 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 100% by mass or less. , preferably 95% by mass or less, more preferably 90% by mass or less, and even 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 4 or more, still more preferably 6 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 the like, preferably 2-ethylhexyl (meth) acrylate or ( Meth)stearyl acrylate, more preferably 2-ethylhexyl acrylate, stearyl methacrylate, and still more preferably stearyl methacrylate.
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 amorphous polyester-based resin A preferably has structural units derived from bi-reactive monomers that are covalently bonded to polyester resin segments and addition polymerized resin segments.
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.
Examples of addition polymerizable groups include carbon-carbon unsaturated bonds (ethylenically 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.
When the bireactive monomer is an addition polymerizable monomer having a carboxy group, the amount of the structural unit derived from the bireactive monomer is preferably based on 100 mol parts of the alcohol component of the polyester resin segment of the amorphous polyester resin A. is 1 mol part or more, more preferably 5 mol parts or more, still more preferably 8 mol parts or more, and is preferably 30 mol parts or less, more preferably 25 mol parts or less, still more preferably 20 mol parts or less.

In addition to the polyester resin segment and the addition polymerized resin segment, the amorphous polyester-based resin A is a structural unit derived from a hydrocarbon wax having at least one of a carboxy group and a hydroxyl group (a structural unit derived from a hydrocarbon wax). may contain

The content of the polyester resin segment in the amorphous polyester resin A is preferably 40% by mass or more, more preferably 45% by mass or more, still more preferably 45% by mass or more, based on the total amount of the polyester resin segment and the addition polymerized resin segment. It is 55% by mass or more, and preferably 95% by mass or less, more preferably 85% by mass or less, and even more preferably 75% by mass or less. In addition, let the structural unit derived from a bi-reactive monomer be a polyester resin segment.

The content of the addition polymerized resin segment in the amorphous polyester resin A is preferably 5% by mass or more, more preferably 15% by mass or more, and still more preferably, based on the total amount of the polyester resin segment and the addition polymerized resin segment. is 25% by mass or more, and preferably 60% by mass or less, more preferably 55% by mass or less, and even more preferably 45% by mass or less. In addition, let the structural unit derived from a bi-reactive monomer be a polyester resin segment.

The amount of the structural unit derived from the bi-reactive monomer in the amorphous polyester resin A is preferably 0.1% by mass or more, more preferably 0.1% by mass or more, based on the total amount of the polyester resin segment and the addition polymerized resin segment. It is 5% by mass or more, more preferably 0.8% by mass or more, and preferably 10% by mass or less, more preferably 7% by mass or less, and even more preferably 4% by mass or less.

The amount of the hydrocarbon wax-derived structural unit in the amorphous polyester resin A is preferably 10 parts by mass or less, more preferably 8 parts by mass, with respect to 100 parts by mass of the total amount of the polyester resin segment and the addition polymerized resin segment. parts or less, more preferably 6 parts by mass or less.

The above amount is calculated based on the ratio of the amounts of the polyester resin segment, the raw material monomer of the addition polymerization resin segment, the bi-reactive monomer, and the radical polymerization initiator, and the mass excluding the dehydration amount due to polycondensation in the polyester resin segment Standard. When a radical polymerization initiator is used, the mass of the radical polymerization initiator is included in the addition polymerization resin segment in the calculation.

Amorphous polyester resin A is produced by a method including, for example, step A of polycondensing an alcohol component and a carboxylic acid component, and step B of addition polymerizing a raw material monomer and a bireactive monomer for an addition polymerized resin segment. may
When the amorphous polyester-based resin A further has a structural unit derived from a hydrocarbon wax, in the above step A, for example, in the presence of a hydrocarbon wax having at least one of a hydroxyl group and a carboxyl group, an alcohol component and a carboxylic A polycondensation reaction of the acid component is carried out.
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 carried out. A method of further advancing the polycondensation reaction with the carboxy group of the constituent site derived from the reactive monomer is preferred.

In step A, if necessary, an esterification catalyst such as di(2-ethylhexanoic acid) tin (II), dibutyltin oxide, titanium diisopropoxybis(triethanolamine) is added to the alcohol component and the carboxylic acid component. 0.01 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the total amount of; Polycondensation may be carried out using 0.001 parts by mass or more and 0.5 parts by mass or less per 100 parts by mass of the total amount.
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.

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) such as 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 amorphous polyester resin A)
The softening point of the amorphous polyester resin A is preferably 70° C. or higher, more preferably 90° C. or higher, and still more preferably 100° C. or higher. Below, more preferably 140° C. or less, still more preferably 125° C. or less.
The glass transition temperature of the amorphous polyester resin A is preferably 30° C. or higher, more preferably 35° C. or higher, and still more preferably 40° C. or higher. °C or less, more preferably 70°C or less, and even more preferably 60°C or less.

The acid value of the amorphous polyester 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, more preferably 30 mgKOH/g or less.
The softening point, glass transition temperature, and acid value of the amorphous polyester-based resin A can be appropriately adjusted depending on the type and amount of raw material monomer used, and the production conditions such as reaction temperature, reaction time, and cooling rate. Moreover, those values are determined by the method described in Examples.
When two or more amorphous polyester resins A 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 content of the amorphous polyester 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 still more preferably It is 65% by mass or more and 100% by mass or less, preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 87% by mass or less.

<<Crystalline polyester resin C>>
In the present invention, the toner base particles preferably contain a crystalline polyester resin C, more preferably the toner base particles have a core-shell structure and contain the crystalline polyester resin C in the core portion. It is more preferable to contain the crystalline polyester resin C only in.

The crystalline polyester resin C is, for example, a crystalline polyester resin that 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, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 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 tetradecanedioic 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, it is 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.

The crystalline polyester resin C is produced, for example, by polycondensation of an alcohol component and a carboxylic acid component.
At the time of polycondensation, an esterification catalyst such as di(2-ethylhexanoic acid) tin (II), dibutyltin oxide, titanium diisopropoxybis(triethanolamine), or the like is added to the alcohol component and the carboxylic acid, if necessary. 0.01 parts by mass or more and 5 parts by mass or less with respect to the total amount of 100 parts by mass with the acid component; Polycondensation may be carried out using 0.001 parts by mass or more and 0.5 parts by mass or less per 100 parts by mass of the total amount of the components.
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.

(Physical properties of crystalline polyester resin C)
The softening point of the crystalline polyester 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 toner storage stability, and from the viewpoint of further improving low-temperature fixability. Therefore, the temperature is preferably 150° C. or lower, more preferably 120° C. or lower, still more preferably 100° C. or lower, and still more preferably 95° C. or lower.
The melting point of the crystalline polyester resin C is preferably 50° C. or higher, more preferably 60° C. or higher, and still more preferably 70° C. or higher from the viewpoint of toner storage stability, and from the viewpoint of further improving low-temperature fixability. , preferably 100° C. or lower, more preferably 90° C. or lower, still more preferably 85° C. or lower, still more preferably 80° C. or lower.

The acid value of the crystalline polyester resin C is preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, still more preferably 15 mgKOH/g or more, and preferably 35 mgKOH/g or less, more preferably 25 mgKOH/g. Below, more preferably 20 mgKOH/g or less.

The softening point, melting point, and acid value of the crystalline polyester resin C can be appropriately adjusted depending on the type and amount of the raw material monomer used, and the production conditions such as the reaction temperature, reaction time, and cooling rate. It is obtained by the method described in . When two or more crystalline polyester 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.

When the amorphous polyester resin A and the crystalline polyester resin C are used together, the mass ratio of the amorphous polyester resin A and the crystalline polyester resin C [amorphous polyester resin A/crystalline polyester resin C] is preferably 40/60 or more, more preferably 50/50 or more, more preferably 60/40 or more, still more preferably 65/35 or more, and preferably 95/5 or less, more preferably 90/10 Below, more preferably 85/15 or less, still more preferably 75/25 or less.

[Core-shell structure]
The toner of the present invention preferably has a core-shell structure, and the core contains the crystalline polyester resin C and the amorphous polyester resin A. In addition to the crystalline polyester resin C and the amorphous polyester resin A, the core portion preferably contains a colorant and a release agent.

In the present invention, the content of the shell in the toner particles is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, still more preferably 100 parts by mass of the toner base particles, from the viewpoint of obtaining high-definition images. It is 7 parts by mass or more, more preferably 10 parts by mass or more, and preferably 30 parts by mass or less, more preferably 25 parts by mass or less, and even more preferably 20 parts by mass or less.
The shell in the toner preferably contains the amorphous polyester resin B described later, and more preferably the shell is made of the amorphous polyester resin B.
The amount of the shell binder resin in 100 parts by mass of the binder resin of the toner is 5 parts by mass or more, preferably 7 parts by mass or more, and more preferably 10 parts by mass or more, from the viewpoint of obtaining high-definition images. Yes, and 30 parts by mass or less, preferably 25 parts by mass or less, more preferably 20 parts by mass or less.

<<Amorphous polyester resin B>>
In the present invention, the toner base particles preferably contain an amorphous polyester-based resin B in addition to the crystalline polyester resin C and the amorphous polyester resin A as a binder resin, and the shell is an amorphous polyester resin. It is more preferable to contain system resin B.
The amorphous polyester-based resin B is preferably an amorphous polyester-based resin containing, for example, a polycondensate of an alcohol component and a carboxylic acid component.
Polyester resins include polyester resins and modified polyester resins. Modified polyester resins include, for example, urethane-modified polyester resins, epoxy-modified polyester resins, and composite resins containing polyester resin segments and addition polymerized resin segments. Among these, amorphous polyester resins, which are polycondensates of alcohol components and carboxylic acid components, are preferred.

The alcohol component is an alkylene oxide adduct of an aromatic diol similar to the alcohol component of the polyester resin segment of the amorphous polyester resin A described above, a linear or branched aliphatic diol, an alicyclic diol, a trivalent or higher poly Among them, alkylene oxide adducts of aromatic diols are preferred, more preferably alkylene oxide adducts of bisphenol A, still more preferably bisphenol A [2 , 2-bis(4-hydroxyphenyl)propane] and ethylene oxide adduct of bisphenol A. These may use 1 type(s) or 2 or more types. Among these, the ethylene oxide adduct of bisphenol A is more preferable.

Examples of the carboxylic acid component include dicarboxylic acids similar to the carboxylic acid component of the polyester resin segment of the amorphous polyester resin A described above, 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 preferable.
The amount of the aromatic dicarboxylic acid in the carboxylic acid component is preferably 40 mol% or more, more preferably 50 mol% or more, still more preferably 60 mol% or more, still more preferably 70 mol% or more, and preferably 95 mol% or less, It is more preferably 90 mol % or less, still more preferably 85 mol % or less.

The amount of linear or branched aliphatic dicarboxylic acid is preferably 1 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more, and preferably 60 mol% or less, more preferably 60 mol% or less, in the carboxylic acid component. is 30 mol % or less, more preferably 20 mol % or less, still more preferably 15 mol % or less.

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% or more in the carboxylic acid component. , and preferably 30 mol % or less, more preferably 25 mol % or less, and 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.

Polyester-based resin B may be produced, for example, by step A of polycondensing an alcohol component and a carboxylic acid component.
The step A is the same as the step A described in the method for producing the amorphous polyester resin A, and the preferred range is also the same.

(Physical properties of amorphous polyester resin B)
The softening point of the amorphous polyester resin B is preferably 70° C. or higher, more preferably 90° C. or higher, and still more preferably 100° C. or higher. Below, more preferably 140° C. or less, still more preferably 125° C. or less.
The glass transition temperature of the amorphous polyester resin B is preferably 30° C. or higher, more preferably 40° C. or higher, and still more preferably 50° C. or higher. °C or less, more preferably 80°C or less, and even more preferably 70°C or less.

The acid value of the amorphous polyester 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 30 mgKOH. /g or less, more preferably 25 mgKOH/g or less.
The softening point, glass transition temperature, and acid value of the amorphous polyester-based resin B can be appropriately adjusted depending on the type and amount of raw material monomer used, and the production conditions such as reaction temperature, reaction time, and cooling rate. Moreover, those values are determined by the method described in Examples.
When two or more amorphous polyester 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 content of the amorphous polyester resin B is preferably 60% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass, based on the total amount of the resin components of the resin particles Y for the shell layer. Above, more preferably 95% by mass or more, and 100% by mass or less, more preferably 100% by mass.

[Coloring agent]
In the present invention, the toner base particles preferably contain a colorant, and preferably contain a colorant in the core portion.
As the colorant, all dyes, pigments, etc. used as colorants for toners can be used.
Examples of colorants include carbon black, phthalocyanine blue (eg, pigment blue 15:3), permanent brown FG, brilliant first scarlet, pigment green B, rhodamine-B base, solvent red 49, solvent red 146, and solvent blue 35. , quinacridone, carmine 6B, disazo yellow. The toner may be black toner or color toner other than black.
The content of the colorant in the toner particles is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, and is preferably 25% by mass or less, more preferably 20% by mass. % or less, more preferably 15 mass % or less.

〔Release agent〕
In the present invention, the toner base particles preferably contain a release agent, and more preferably contain a release agent in the core portion.
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 use 1 type(s) or 2 or more types.

The melting point of the release agent is preferably 60° C. or higher, more preferably 70° C. or higher, and is preferably 160° C. or lower, more preferably 140° C. or lower, still more preferably 120° C. or lower, and still more preferably 100° C. or lower. is.
The content of the release agent in the toner particles is preferably 0.1% by mass or more, more preferably 1% by mass or more, still more preferably 3% by mass or more, and still more preferably 5% by mass or more. is 20% by mass or less, more preferably 15% by mass or less.

<Method for producing toner base particles>
The method for producing the toner base particles is not particularly limited as long as the toner base particles having a desired degree of circularity can be obtained. From the viewpoint of obtaining the desired degree of circularity of 0.965 or more, it is preferable to employ a chemical method such as an emulsion polymerization method or a suspension method. Furthermore, from the viewpoint of obtaining a toner having excellent toner physical properties such as low-temperature fixability, the toner base particles are preferably obtained by emulsion aggregation including the following steps 1 to 3.
Step 1: A step of aggregating resin particles X containing crystalline polyester resin C and amorphous polyester resin A in the same or different particles in an aqueous medium to obtain aggregated particles 1;
Step 2: A step of aggregating the resin particles Y containing the amorphous polyester-based resin B to the aggregated particles 1 obtained in the step 1 to obtain aggregated particles 2;
Step 3: Step of heating and fusing the aggregated particles 2 obtained in Step 2 to obtain fused particles A method for producing toner base particles in Steps 1 to 3 includes, for example, JP-A-2021-012242. Step 1, Step 1′, and Step 2 described in the publication, and Step 1, Step 1′, and Step 2 described in JP-A-2021-026129 are referred to.

In step 1 above, it is preferable to agglomerate colorant particles containing a colorant and releasing agent particles containing a releasing agent together with the resin particles X.
The dispersion of resin particles X is preferably obtained by a phase inversion emulsification method.
Further, the colorant particles are preferably mixed with the resin particles as a dispersion liquid of the colorant particles and aggregated to be contained in the aggregated particles. It is preferable to obtain by dispersing using a dispersing machine. From the viewpoint of improving the dispersion stability of the colorant, the dispersion is carried out in the presence of an addition polymer (hereinafter, the addition polymer used for dispersing the colorant is also referred to as "addition polymer E") or a surfactant. It is preferable to use
Examples of the surfactant include nonionic surfactants, anionic surfactants, and cationic surfactants.
The addition polymer E preferably has structural units derived from the addition polymerizable monomer a having an aromatic group, and further includes an addition polymerizable monomer b having an ionic group and an addition polymerizable monomer c having a polyalkylene oxide group. , and macromonomer d. For the colorant particle dispersion and the addition polymer E, the addition polymer E described in JP-A-2021-026129 is referred to.
Further, the release agent particles are preferably mixed as a release agent particle dispersion with the resin particle dispersion and the colorant particle dispersion and aggregated to be contained in the aggregated particles.
Although a dispersion of release agent particles can be obtained using a surfactant, it is preferably obtained by mixing the release agent and resin particles Z. 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 it is more preferable to use a composite resin D having a polyester resin segment and an addition polymerized resin segment. Regarding the release agent particle dispersion and the composite resin D, JP-A-2021-026129 is referred to.
Further, after the step 3, a post-treatment step may be performed, and it is preferable to obtain the toner base particles by isolation. Since the particles obtained in the step 3 are present in the aqueous medium, it is preferable that the particles are first subjected to solid-liquid separation, followed by washing and drying as necessary.

[Volume Average Particle Diameter of Toner Base Particles]
It is preferable to add an external additive, which will be described later, to the surface of the toner base particles obtained by performing drying or the like, and use it as the toner for electrostatic charge image development.
The volume-median particle size (D ₅₀ ) of the toner base particles is preferably 2 μm or more, more It is preferably 3 µm or more, more preferably 4 µm or more, and preferably 10 µm or less, more preferably 8 µm or less, and even more preferably 6 µm or less.
The CV value of the toner base particles is preferably 12% or more, more preferably 14% or more, and still more preferably 16% or more from the viewpoint of improving toner productivity, and from the viewpoint of obtaining high-quality images. , preferably 32% or less, more preferably 30% or less, and still more preferably 29% or less.

<External Additives>
In the present invention, the toner for developing an electrostatic charge image includes toner base particles having a circularity of 0.965 or more, silica particles having a small particle size of 10 nm or more and 30 nm or less as calculated from the specific surface area, and large-diameter silica particles having a particle diameter of 70 nm or more and 190 nm or less are externally added. In addition, the mass ratio of the added amount of the large-diameter silica particles and the small-diameter silica particles (large-diameter silica particles/small-diameter silica particles) is 7 or more and 18 or less.
When the mass ratio is 7 or more, the toner has appropriate surface unevenness, friction with the developing blade is appropriately generated, and the toner is uniformly charged, thereby suppressing the occurrence of fogging. In addition, since a suitable amount of friction is generated against the developing roller and a necessary transport amount is obtained, a good image density can be obtained. Further, when it is 18 or less, the friction between the developing roller and the electrostatic image developing toner does not become excessively large, and the amount of toner conveyed does not increase excessively, so that the amount of toner scraped off by the developing blade is appropriate. It is within the range, and the occurrence of toner leakage from the end of the developing roller is suppressed.
The mass ratio of the added amount of the large-diameter silica particles and the small-diameter silica particles (large-diameter silica particles/small-diameter silica particles) is 7 or more, preferably 8 or more, more preferably 9 or more, and further It is preferably 10 or more and 18 or less, preferably 16 or less, more preferably 15 or less, still more preferably 14 or less.

The amount of the small-diameter silica particles added to 100 parts by mass of the toner base particles is preferably 0.4 parts by mass from the viewpoint of improving the transferability, suppressing the occurrence of fogging, and improving the stability of the image density. above, more preferably 0.45 parts by mass or more, and preferably 1.2 parts by mass or less, more preferably 1.0 parts by mass or less, even more preferably 0.7 parts by mass or less, and even more preferably 0 0.65 parts by weight or less, more preferably 0.6 parts by weight or less.
From the same viewpoint, the amount of large-diameter silica particles added to 100 parts by mass of toner base particles is preferably 5 parts by mass or more, more preferably 6 parts by mass or more, and preferably 18 parts by mass or less. It is more preferably 14 parts by mass or less, still more preferably 10 parts by mass or less.
From the same viewpoint, the total amount of the large-diameter silica particles and the small-diameter silica particles added to 100 parts by mass of the toner base particles is preferably 5.5 parts by mass or more, more preferably 6 parts by mass or more, and still more preferably It is 6.5 parts by mass or more, and preferably 19 parts by mass or less, more preferably 15 parts by mass or less, and even more preferably 12 parts by mass or less.

The small-diameter silica particles have a particle size converted from the specific surface area of 10 nm or more, preferably 12 nm or more, more preferably 14 nm or more, still more preferably 16 nm or more, still more preferably 20 nm or more, and 30 nm. or less, preferably 28 nm or less.
In addition, the large-diameter silica particles have a particle diameter converted from the specific surface area of 70 nm or more, preferably 90 nm or more, more preferably 100 nm or more, and 190 nm or less, preferably 150 nm or less, more preferably 150 nm or less. is 140 nm or less, more preferably 125 nm or less.
The "particle diameter converted from the specific surface area" in the small particle size silica particles and the large particle size silica particles is measured by the method described in Examples.

In the toner to which the above-mentioned small-diameter silica particles and large-diameter silica particles are externally added, the particle size of the external additive as a whole is plotted on the horizontal axis and the mass of particles having the relevant particle size on the vertical axis. It has two peaks at a diameter of 10 nm or more and 30 nm or less and a particle diameter of 70 nm or more and 190 nm or less.
Further, W _S is the mass ratio of particles with a particle size of 10 nm or more and 70 nm or less converted from the specific surface area in the external additive, and W is the mass ratio of particles with a particle size of more than 70 nm and 400 nm or less converted from the specific surface area. When _L is, W _L /W _S is preferably 7 or more, more preferably 8 or more, still more preferably 9 or more, still more preferably 10 or more, and preferably 18 or less, and more It is preferably 16 or less, more preferably 15 or less, and even more preferably 14 or less.

From the viewpoint of improving the toner transferability, the small-diameter silica particles and the large-diameter silica particles are preferably hydrophobic silica that has been subjected to hydrophobizing treatment.
Silane coupling agents and silicone oils are examples of hydrophobizing agents that hydrophobize the surfaces of silica particles.
Silane coupling agents include disilazane such as hexamethyldisilazane (HMDS); cyclic silazane; trimethylsilane; trimethylchlorosilane; Silane, isobutyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, trimethylmethoxysilane, octyltriethoxysilane, hydroxypropyltrimethoxysilane, phenyltrimethoxysilane, n-octadecyltrimethoxysilane, vinyltrimethoxysilane, vinyltrimethoxysilane, Alkylsilane compounds such as ethoxysilane, γ-methacryloxypropyltrimethoxysilane, and vinyltriacetoxysilane, as well as γ-aminopropyltriethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-(2 -aminoethyl)aminopropylmethyldimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)3-aminopropyltrimethoxysilane, and N-β-(N-vinylbenzylaminoethyl )-aminosilane compounds such as γ-aminopropyltrimethoxysilane;
Examples of the silicone oil include polydimethylsiloxane, polymethylhydrogensiloxane, polymethylphenylsiloxane, and amino-modified silicone oil.
Among these, hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), polydimethylsiloxane, octyltriethoxysilane (OTES), and polydimethylsiloxane are preferred.
These can be used alone or in combination of two or more.

A mixer such as a Henschel mixer can be used to mix the toner base particles and the external additive.

Charged particles (charging assistant) may be added to the toner base particles in addition to the small-diameter silica particles and large-diameter silica particles described above.
It is preferable to externally add charged particles having a charging polarity different from the charging polarity of the toner base particles, and when the toner base particles are positively charged, it is preferable to externally add negatively charged charged particles. When the toner base particles are negatively charged, it is preferable to externally add positively charged particles.
Here, when the toner base particles are toner base particles having a polyester-based resin as a binder resin as described above, since the toner base particles are negatively charged, positively charged particles are externally added. preferably.
The number average primary particle size of the charged particles is preferably 0.10 μm or more and 1.50 μm or less. More preferably, it is 0.150 μm or more and 1.00 μm or less.
Having such charged particles is preferred because of good transfer efficiency through continuous use. It is believed that the charged particles having this particle size are able to roll on the surface of the toner particles, promoting the charging of the toner, and consequently suppressing the decrease in charging due to the application of the transfer bias.

Examples of positively charged particles include hydrotalcite particles, titanium oxide particles, benzoguanamine resin particles, benzoguanamine-melamine resin particles, melamine resin particles, and melamine-formaldehyde resin particles. Among these, melamine-formaldehyde resin particles are particularly preferred.
Examples of negatively charged particles include polytetrafluoroethylene particles, trifluoroethylene particles, vinylidene fluoride particles, and fluoroethylene resin particles.

The amount of the charged particles added to 100 parts by mass of the toner base particles is preferably 0.005 parts by mass or more, more preferably 0.01 parts by mass or more, still more preferably 0.03 parts by mass or more, and preferably 1 part by mass. 0.0 parts by mass or less, more preferably 0.3 parts by mass or less, and even more preferably 0.1 parts by mass or less.

≪Toner for electrostatic charge image development≫
The electrostatic charge image developing toner obtained as described above can be used as a one-component developer, or can be mixed with a carrier and used as a two-component developer. Among these, it is suitable as a one-component developer, and more suitable as a non-magnetic one-component developer.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited to these Examples. Each property value was measured and evaluated by the following methods.
In addition, in notations such as "alkylene oxide (X)", the numerical value X in parentheses means the average number of added moles of the alkylene oxide.

[measurement]
[Acid value of resin]
Measured according to JIS K0070:1992. However, chloroform was used as the measurement solvent.

[Resin softening point, crystallinity index, melting point, 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 "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, and the temperature was lowered to 0 at a cooling rate of 10 ° C./min. Cooled to °C. 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 "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of a sample was weighed in an aluminum pan and heated to 200 ° C. , and then cooled to 0° C. at a cooling rate of 10° C./min. Then, the temperature of the sample was increased at a temperature increase rate of 10°C/min, and the calorie was measured. Among the observed endothermic peaks, the temperature of the peak with the maximum peak area was defined 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, when a peak is observed, the temperature of the peak is measured. The temperature at the point of intersection with the extended line of the baseline on the low temperature side was defined as the glass transition temperature.

[Weight Average Molecular Weight of Addition Polymer]
Gel permeation chromatography [GPC apparatus "HLC-8320GPC" ( Tosoh Corporation), columns "TSKgel Super AWM-H", "TSKgel SuperAW3000", "TSKgel guardcolumn Super AW-H" (manufactured by Tosoh Corporation), flow rate: 0.5 mL / min], the molecular weight is known as a standard substance monodisperse polystyrene kit [PStQuick B (F-550, F-80, F-10, F-1, A-1000), PStQuick C (F-288, F-40, F-4, A-5000, A -500), manufactured by Tosoh Corporation].

[Melting point of release agent]
Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, heated to 200 ° C., and then cooled at a rate of 10 ° C. /min to 0°C. Next, the temperature of the sample was raised at a temperature elevation rate of 10° C./min, the calorie was measured, and the maximum endothermic peak temperature was defined as the melting point.

[Volume-median particle size _D50 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: Distilled water was added to the measurement cell, and the volume-median particle size _D50 and the volume-average particle size were measured at a concentration that brought the absorbance to the appropriate range. Also, the CV value (variation coefficient of particle size distribution, %) 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 drying temperature of 150 ° C. and in measurement mode 96 (monitoring time 2.5 min / fluctuation width 0.05%). Moisture content (mass %) was measured. The solid content concentration was calculated according to the following formula.
Solid content concentration (mass%) = 100 - moisture (mass%)

[Volume median particle diameter _D50 and CV value of aggregated particles]
The volume median particle size _D50 of the 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, then 30,000 particles are measured, and the particle size distribution The volume median particle diameter _D50 and the volume average particle diameter were determined from. Also, the CV value (variation coefficient of particle size distribution, %) was calculated according to the following formula.
CV value (%) = (standard deviation of particle size distribution/volume average particle size) x 100

[Circularity of Fusion Particles and Toner Base Particles]
The circularity of the fusible particles and toner base 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 fusible particles or toner base 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 instrument, aperture diameter, analysis software, and electrolytic solution used were the same as those used for the volume-median particle diameter _D50 of the aggregated particles.
- Dispersion: Polyoxyethylene lauryl ether "Emulgen (registered trademark) 109P" (manufactured by Kao Corporation, HLB: 13.6) was dissolved in the electrolytic solution to obtain a dispersion having a concentration of 5% by mass.
Dispersion conditions: 10 mg of a toner measurement sample was added to 5 mL of the dispersion liquid, dispersed for 1 minute with an ultrasonic disperser, then 25 mL of an electrolytic solution was added, and dispersed for 1 minute with an ultrasonic disperser. , 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 determined from the distribution.
Also, the CV value (variation coefficient of particle size distribution, %) was calculated according to the following formula.
CV value (%) = (standard deviation of particle size distribution/volume average particle size) x 100

[Particle size of external additive]
The particle size of the external additive was calculated according to the following formula from the specific surface area, assuming that the particle shape of the external additive is a perfect sphere and the density of the silica particles used as the external additive is 2.2 g/cm ² .
Particle size (m) = 6/(specific surface area ( ^m2 /g) x density ⁽ g/m3))
The value of the specific surface area (m ² /g) used in the above formula was obtained using the BET multipoint method with a specific surface area measuring device. In the BET multipoint method, the adsorption amount was measured at three or more points within the range of 0.05 to 0.30 in the equilibrium relative pressure of the adsorbed gas (nitrogen), and the specific surface area was calculated. Specifically, analysis is performed under the following measurement conditions.
・ Measuring device: Multi-sample high-performance specific surface area / pore size distribution measuring device 3Flex-3MP (manufactured by Micromeritics)
・Dispersed adsorbate: Nitrogen ・Pretreatment: 40°C, 4 hours or more ・Equilibrium relative pressure: 0.05 to 0.30 (every 0.05)
Equilibrium interval: 10 seconds

[Evaluation method]
[Test conditions for fogging]
Toner is mounted on a commercially available printer "COREFIDO C712dnw" (manufactured by Oki Data Co., Ltd.) and printed on high-quality paper "Excellent White Paper A4 size" (manufactured by Oki Data Co., Ltd.) at a temperature of 25 ° C and a humidity of 50% (NN environment). , After continuously printing 2,000 sheets with an image with a print density of 0.3%, leave it for 12 hours in an environment with a temperature of 27 ° C. and a humidity of 80% (HH environment), and further 1,000 sheets in the HH environment. Continuous printing was performed, and a total of 3,000 sheets were printed under the NN environment and the HH environment. The measurement of fogging was carried out when the number of printed sheets was the first, and then after every 500 sheets. In addition, the measurement was also performed for the first sheet when the NN environment was changed to the HH environment.

[Measurement of fog]
Fog was measured as follows.
First, blank paper printing was performed, and the printer was stopped in the middle of blank paper printing. The developing unit was taken out from the printer, and "Scotch (registered trademark) Mending Tape 810" (manufactured by 3M Japan Co., Ltd., width: 18 mm) was adhered on the photoreceptor, and the toner on the photoreceptor was peeled off with the tape.
The tape peeled from the photoreceptor and the unused tape are pasted on high-quality paper "Excellent White Paper A4 size" (manufactured by Oki Data Co., Ltd.), and the color of the tape peeled from the photoreceptor and the unused tape is measured. Measurement was performed with a meter "SpectroEye" (manufactured by GretagMacbeth, light irradiation conditions; standard light source D50, observation field of view 2°, density standard DINNB, absolute white standard). The color difference (ΔE) between the tape peeled from the photoreceptor and the unused tape was defined as fog. The smaller the fog value, the better the image without fog. Table 5 shows the results. Regarding the fog value, the measured value when the number of printed sheets is the first, the measured value every 500 sheets until the total of 3,000 sheets under the NN environment and the HH environment, and the value measured from the NN environment to the HH environment. The average value of the measured values of the first sheet when the thickness was changed was used.

[Conveyance test conditions]
Toner is mounted on a commercially available printer "COREFIDO C712dnw" (manufactured by Oki Data Co., Ltd.) and printed on high-quality paper "Excellent White Paper A4 size" (manufactured by Oki Data Co., Ltd.) at a temperature of 25 ° C and a humidity of 50% (NN environment). , After continuously printing 2,000 sheets with an image with a print density of 0.3%, leave it for 12 hours in an environment with a temperature of 27 ° C. and a humidity of 80% (HH environment), and further 1,000 sheets in the HH environment. Continuous printing was performed, and a total of 3,000 sheets were printed under the NN environment and the HH environment. The transport amount was measured every 1,000 sheets after measuring the first sheet. Also, the transport amount was measured for the first sheet when the environment was changed from the NN environment to the HH environment.

[Measurement of conveyed amount]
First, a solid image is printed, and the printer is stopped when half of A4 is transferred. /m meter "210HS" (manufactured by Trek) was used to absorb the toner on the developing roller. The amount of toner per unit area on the developing roller was calculated by dividing the amount of toner sucked by the area of the sucked toner, and this was used as the transport amount. As for the value of the transport amount, if it is 0.20 mg/cm ² or ^more , the image density after printing can be ensured. , or less is desirable. In addition, it is desirable that the transport amount be stable regardless of the number of printed sheets and the printing environment. Table 5 shows the results. Regarding the value of the transport amount, the measured value when the number of printed sheets is 1, the measured value for each 1,000 sheets until the total of 3,000 sheets under the NN environment and HH environment, and the value from the NN environment The average value of the measured values of the first sheet when changed to the HH environment was used. The standard deviation is also shown in Table 5 in order to judge whether the conveyed amount is stable.

[Resin production]
[Production of amorphous resin]
Production Example A1 (Production of 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 3356 g of propylene oxide (2.2) adduct of bisphenol A, 955 g of terephthalic acid, and paracol were added. 6490 (manufactured by Nippon Seiro Co., Ltd.) 385 g, di(2-ethylhexanoic acid) tin (II) 25 g, and 3,4,5-trihydroxybenzoic acid 2.5 g were added and heated to 235°C under a nitrogen atmosphere while stirring. and held at 235° C. 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 2198 g of styrene, 550 g of stearyl methacrylate, 110 g of acrylic acid, and 330 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 pressure was held at 8 kPa for 1 hour. Then, after returning to atmospheric pressure, the temperature was cooled to 190°C, 200 g of fumaric acid, 194 g of sebacic acid, 184 g of trimellitic anhydride, and 2.5 g of 4-tert-butylcatechol were added, and the temperature was increased to 210°C at 10°C/hr. After that, the reaction was carried out at 4 kPa to the desired softening point to obtain Resin A-1. Physical properties are shown in Table 1.

Production Example A2 (Production of Resin B-1)
The inside of a four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 3265 g of ethylene oxide (2.2) adduct of bisphenol A, 1334 g of terephthalic acid, and di(2-ethylhexane) were added. Acid) 25 g of tin (II) and 2.5 g of 3,4,5-trihydroxybenzoic acid are added, and the temperature is raised to 235°C while stirring under a nitrogen atmosphere, and after maintaining at 235°C for 6 hours, The pressure in the flask was lowered and maintained at 8.3 kPa for 1 hour. Then, after returning to atmospheric pressure, cool to 180° C., add 73 g of adipic acid, 135 g of dodecenylsuccinic anhydride, and 193 g of trimellitic anhydride, raise the temperature to 220° C. at a rate of 10° C./hr, and then place it in the flask. The pressure was lowered and the reaction was carried out at 10 kPa to the desired softening point to obtain Resin B-1. Physical properties are shown in Table 1.

Production Example A3 (Production of Resin A-2)
The inside of a four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was purged with nitrogen, and 3558 g of propylene oxide (2.2) adduct of bisphenol A and ethylene oxide (2.2) of bisphenol A were added. 1416 g of the adduct, 1229 g of terephthalic acid, 1518 g of dodecenylsuccinic anhydride, and 40 g of di(2-ethylhexanoic acid)tin (II) were added, and the temperature was raised to 230°C under a nitrogen atmosphere with stirring. After holding for 1 hour, the pressure in the flask was further lowered and held at 8.3 kPa for 1 hour. Then, after cooling to 215 ° C. and returning to atmospheric pressure, 279 g of trimellitic anhydride was added, and after holding at 215 ° C. for 1 hour, the pressure in the flask was further lowered and held at 8.3 kPa for 3 hours. to obtain Resin A-2. Physical properties are shown in Table 1.

Production Example A4 (Production of Resin D-1)
Resin D-1 was obtained in the same manner as in Production Example A1, except that the raw material composition was changed as shown in Table 1. Physical properties are shown in Table 1.

[Production of crystalline polyester resin]
Production Example C1 (Production of Resin C-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, 3416 g of 1,10-decanediol and 4084 g of sebacic acid were added, and while stirring, 135 C. and held at 135.degree. C. for 3 hours, then heated from 135.degree. C. to 200.degree. C. over 10 hours. Then, 23 g of tin (II) di(2-ethylhexanoate) was added, and the temperature was maintained at 200° C. for 1 hour. C-1 was obtained. Physical properties are shown in Table 2.

[Production of resin particle dispersion]
Production Example X1 (Production of Resin Particle Dispersion X-1)
210 g of Resin A-1, 90 g of Resin C-1, and 360 g of methyl ethyl ketone were placed in a container with an internal volume of 3 L equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen inlet tube, and the mixture was heated at 73°C. Two hours were allowed to dissolve the resin. A 5% by mass sodium hydroxide aqueous solution was added to the obtained 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 30 minutes.
Next, 600 g of deionized water was added over 60 minutes while stirring at 280 r/min (peripheral speed of 88 m/min) while maintaining the temperature at 73° C., and phase inversion emulsification was performed. Methyl ethyl ketone was distilled off under reduced pressure while the temperature was maintained at 73° C. to obtain an aqueous dispersion. Thereafter, the aqueous dispersion is cooled to 30°C while stirring at 280 r/min (peripheral speed of 88 m/min), and then deionized water is added so that the solid content concentration becomes 20% by mass, thereby dispersing the resin particles. Liquid X-1 was obtained. Table 3 shows the volume-median particle diameter _D50 and CV value of the obtained resin particles.

Production Example X2 (Production of Resin Particle Dispersion X-2)
300 g of resin A-2, 360 g of methyl ethyl ketone, and 59 g of deionized water were placed in a container with an internal volume of 3 L equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen inlet tube, and the mixture was heated at 73° C. for 2 hours. to dissolve the resin. 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 30 minutes.
Next, 600 g of deionized water was added over 60 minutes while stirring at 280 r/min (peripheral speed of 88 m/min) while maintaining the temperature at 73° C., and phase inversion emulsification was performed. While the temperature was maintained at 73° C., methyl ethyl ketone was distilled off under reduced pressure to obtain an aqueous dispersion. After that, the aqueous dispersion is cooled to 30° C. while stirring at 280 r/min (peripheral speed 63 m/min), and then deionized water is added so that the solid content concentration becomes 20% by mass, thereby dispersing the resin particles. Liquid X-2 was obtained. Table 3 shows the volume-median particle diameter _D50 and CV value of the obtained resin particles.

Production Example Y1 (Production of Resin Particle Dispersion Y-1)
300 g of resin B-1 and 360 g of methyl ethyl ketone were placed in a container with an internal volume of 3 L equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer and a nitrogen inlet tube, and the resin was dissolved at 40° C. over 2 hours. let me 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 30 minutes.
Then, while maintaining the temperature at 40° C. and stirring at 280 r/min (peripheral speed of 88 m/min), 600 g of deionized water was added over 60 minutes for phase inversion emulsification. The temperature was raised to 73° C., and methyl ethyl ketone was distilled off under reduced pressure to obtain an aqueous dispersion. Thereafter, the aqueous dispersion is cooled to 30°C while stirring at 280 r/min (peripheral speed of 88 m/min), and then deionized water is added so that the solid content concentration becomes 20% by mass, thereby dispersing the resin particles. Liquid Y-1 was obtained. Table 3 shows the volume-median particle diameter _D50 and CV value of the obtained resin particles.

Production Example Z1 (Production of Resin Particle Dispersion Z-1)
200 g of resin D-1 and 200 g of methyl ethyl ketone are placed in a container having an internal volume of 3 L equipped with a stirrer, reflux condenser, dropping funnel, thermometer and nitrogen inlet tube, and the resin is dissolved at 73° C. for 2 hours. rice field. A 5 mass % sodium hydroxide aqueous solution was added to the obtained solution so that the degree of neutralization was 60 mol % with respect to the acid value of Resin D-1, and the mixture was stirred for 30 minutes.
Next, 700 g of deionized water was added over 50 minutes while stirring at 280 r/min (peripheral speed of 88 m/min) while maintaining the temperature at 73° C. to effect 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. After that, the aqueous dispersion liquid is cooled to 30° C. while stirring at 280 r/min (peripheral speed of 88 m/min), and then deionized water is added so that the solid content concentration becomes 20% by mass, thereby dispersing the resin particles. Liquid Z-1 was obtained. The obtained resin particles had a volume-median particle size _D50 of 0.09 μm and a CV value of 23%.

[Production of Release Agent Particle Dispersion]
Production Example W1 (Production of Release Agent Particle Dispersion W-1)
120 g of deionized water, 86 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 90 to 95 ° C. The mixture was melted while maintaining the temperature at , and stirred to obtain a molten mixture.
While maintaining the temperature of the obtained molten mixture at 90 to 95 ° C., using an ultrasonic homogenizer "US-600T" (manufactured by Nippon Seiki Seisakusho Co., Ltd.), dispersion treatment was performed for 20 minutes, and then cooled to room temperature (20 ° C.). cooled. Deionized water was added to adjust the solid content concentration to 20 mass % to obtain release agent particle dispersion W-1. The volume-median particle size _D50 of the release agent particles in the dispersion was 0.47 μm, and the CV value was 27%.

Production Example W2 (Production of Release Agent Particle Dispersion W-2)
Release agent particle dispersion W-2 was prepared in the same manner as in Production Example W1, except that the release agent used was changed to Fischer-Tropsch wax "FNP-0090" (manufactured by Nippon Seiro Co., Ltd., melting point 90 ° C.). Obtained. The release agent particles in the dispersion had a volume median particle diameter _D50 of 0.45 μm and a CV value of 28%.

[Production of addition polymer]
Production Example E1 (Synthesis of addition polymer E-1)
Methacrylic acid (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.) 16 parts by weight, styrene (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.) 44 parts by weight, styrene macromonomer "AS-6S" (manufactured by Toagosei Co., Ltd., number average molecular weight 6 ,000, solid content 50%) 30 parts by mass (15 parts by mass as solid content), 25 parts by mass of methoxypolyethylene glycol methacrylate "Blenmer PME-200" (NOF Corporation), and 115 parts by mass of the monomer mixture. prepared.
In a reaction vessel, 18 parts by mass of methyl ethyl ketone, 0.03 parts by mass of 2-mercaptoethanol as a chain transfer agent, and 10% (11.5 parts by mass) of the monomer mixture were added and mixed, followed by nitrogen gas replacement. I've done enough.
On the other hand, the remaining 90% (103.5 parts by mass) of the monomer mixture, 0.27 parts by mass of the chain transfer agent, 42 parts by mass of methyl ethyl ketone and 2,2'-azobis(2,4-dimethylvaleronitrile) as a polymerization initiator ) Put a mixture of 3 parts by mass of “V-65” (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) into a dropping funnel, and raise the temperature to 75 ° C. while stirring the mixed solution in the reaction vessel under a nitrogen atmosphere. , the mixed solution in the dropping funnel was dropped over 3 hours. After 2 hours had passed at 75°C from the end of dropping, a solution of 3 parts by mass of the polymerization initiator dissolved in 5 parts by mass of methyl ethyl ketone was added, and the mixture was further aged at 75°C for 2 hours and at 80°C for 2 hours. Thereafter, methyl ethyl ketone was distilled off under reduced pressure drying to obtain an addition polymer E-1. Table 4 shows the weight average molecular weight of the obtained addition polymer.

[Production of colorant particle dispersion]
Production Example F1 (Production of Colorant Particle Dispersion F-1)
75 g of addition polymer E-1 was dissolved in 620 g of methyl ethyl ketone in a container with an internal volume of 5 L equipped with a stirrer equipped with a disper blade, a reflux condenser, a dropping funnel, a thermometer and a nitrogen inlet tube, and then a neutralizer was added. 96 g of a 5% by mass sodium hydroxide aqueous solution and 942 g of deionized water were added as a solution, and the mixture was stirred at 20° C. for 10 minutes with a disper blade. Then, 300 g of a copper phthalocyanine pigment "ECB-301" (manufactured by Dainichiseika Kogyo Co., Ltd., Pigment Blue 15:3) was added, and the mixture was stirred with a disper blade at 6400 rpm at 20° C. for 2 hours. Then, it was passed through a 200-mesh filter and treated with a homogenizer "Microfluidizer M-110EH" (manufactured by Microfluidics) at a pressure of 150 MPa for 15 passes. Methyl ethyl ketone and a portion of water were removed from the resulting dispersion at 70° C. under reduced pressure while stirring. After that, the mixture was passed through a 200-mesh filter and deionized water was added so that the solid content concentration became 20% by mass, thereby obtaining a colorant particle dispersion liquid F-1. The volume median particle diameter _D50 of the colorant particles in the dispersion was 0.12 μm, and the CV value was 21%.

[Toner manufacturing]
Production Example 1 (Preparation of toner base particles 1)
500 g of Resin Particle Dispersion X-1, 35 g of Release Agent Particle Dispersion W-1, and Release Agent Particle Dispersion W are placed in a four-necked flask with an internal volume of 3 L equipped with a dehydration tube, a stirrer, and a thermocouple. -2, 63 g of colorant particle dispersion liquid F-1, 10 g of 10% by mass aqueous solution of polyoxyethylene (50) lauryl ether "Emulgen 150" (manufactured by Kao Corporation, nonionic surfactant), and 10 g of a 15% by mass aqueous solution of sodium dodecylbenzenesulfonate "Neopelex G-15" (manufactured by Kao Corporation, an anionic surfactant) was mixed at a temperature of 25°C. Next, while stirring the mixture, an aqueous solution obtained by dissolving 35 g of ammonium sulfate in 519 g of deionized water was added dropwise with 26 g of a 4.8% by mass potassium hydroxide aqueous solution at 25° C. over 10 minutes. The temperature was raised to 65° C. over 2 hours and maintained at 65° C. until the volume median particle diameter D ₅₀ of the aggregated particles reached 5.9 μm, to obtain a dispersion liquid of aggregated particles 1 .
Subsequently, the dispersion of Aggregated Particles 1 was cooled to 59° C., and 75 g of Resin Particle Dispersion Y-1 was added over 90 minutes while maintaining the temperature at 59° C. Aggregated Particles 1 were aggregated particles in which resin particles were aggregated. A dispersion of 2 was obtained.
To the dispersion of the obtained aggregated particles 2, 41 g of sodium polyoxyethylene lauryl ether sulfate "Emal E-27C" (manufactured by Kao Corporation, an anionic surfactant, effective concentration of 27% by mass), 1396 g of deionized water, and An aqueous solution mixed with 26 g of a 0.1 mol/L sulfuric acid aqueous solution was added. After that, the temperature was raised to 75° C. over 1 hour and maintained at 75° C. for 30 minutes, then 75 g of 0.1 mol/L sulfuric acid aqueous solution was added and further maintained at 75° C. for 15 minutes. Thereafter, 25 g of a 0.1 mol/L sulfuric acid aqueous solution was added again, and the temperature was maintained at 75° C. until the circularity reached 0.970, thereby obtaining a dispersion of fused particles in which aggregated particles were fused.
The resulting fused particle dispersion is cooled to 30° C. and suction filtered to separate the solid content, washed with deionized water at 25° C., and vacuum-dried at 30° C. for 48 hours to form toner mother particles. Particle 1 was obtained. Table 5 shows the physical properties of the toner base particles 1 thus obtained.

Production Examples 2 and 3 (Preparation of toner base particles 2 and 3)
Toner base particles 2 and 3 were produced in the same manner as in Production Example 1, except that the degree of circularity during the fusion bonding process was changed as shown in Table 5. Table 5 shows the physical properties of the obtained toner base particles 2 and 3.

Production Example 4 (Preparation of Toner Base Particles 4)
500 g of Resin Particle Dispersion X-2, 84 g of Release Agent Particle Dispersion W-1 and Colorant Particle Dispersion F- 72 g of 1, 15 g of a 10% by mass aqueous solution of polyoxyethylene (50) lauryl ether "Emulgen 150" (manufactured by Kao Corporation, nonionic surfactant), and 15% by mass of sodium dodecylbenzenesulfonate aqueous solution "Neopelex G -15” (manufactured by Kao Corporation, an anionic surfactant) was mixed at a temperature of 25°C. Next, while stirring the mixture, an aqueous solution of 40 g of ammonium sulfate dissolved in 568 g of deionized water was added with a 4.8% by mass aqueous potassium hydroxide solution to adjust the pH to 8.6. After that, the temperature was raised to 63° C. over 2 hours and maintained at 63° C. until the volume median particle size D ₅₀ of the aggregated particles reached 5.9 μm, to obtain a dispersion liquid of aggregated particles 3 .
Subsequently, the dispersion liquid of aggregated particles 3 was cooled to 59° C., and while maintaining the temperature at 59° C., 75 g of resin particle dispersion liquid Y-1 was added over 90 minutes, and aggregated particles in which resin particles were aggregated to aggregated particles 3 A dispersion of 4 was obtained.
To the dispersion of the obtained aggregated particles 4, 48 g of sodium polyoxyethylene lauryl ether sulfate "Emal E-27C" (manufactured by Kao Corporation, an anionic surfactant, effective concentration of 27% by mass), 600 g of deionized water, and An aqueous solution mixed with 50 g of a 0.1 mol/L sulfuric acid aqueous solution was added. After that, the temperature was raised to 75° C. over 1 hour and maintained at 75° C. for 30 minutes, then 10 g of 0.1 mol/L sulfuric acid aqueous solution was added and further maintained at 75° C. for 15 minutes. Thereafter, 10 g of a 0.1 mol/L sulfuric acid aqueous solution was added again, and the temperature was maintained at 75° C. until the circularity reached 0.970, thereby obtaining a dispersion of fused particles in which aggregated particles were fused.
The resulting fused particle dispersion is cooled to 30° C. and suction filtered to separate the solid content, washed with deionized water at 25° C., and vacuum-dried at 30° C. for 48 hours to form toner mother particles. Particles 4 were obtained. Table 5 shows the physical properties of the toner base particles 4 obtained.

Example 1 (Preparation of Toner 1)
6. Hydrophobic large-diameter silica "RY50" (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: polydimethylsiloxane, particle size calculated from specific surface area; 119 nm) per 100 parts by mass of toner base particles 1; 4 parts by mass, and hydrophobic small particle size silica "R972" (Nippon Aerosil Co., Ltd., hydrophobic treatment agent: dimethyldichlorosilane, particle size converted from specific surface area; 25 nm) 0.5 parts by mass to Henschel mixer The mixture was added, stirred, and passed through a 150-mesh sieve to obtain Toner 1. Table 5 shows the evaluation results of Toner 1 obtained.

Examples 2-5, 8, 10, 11 (Preparation of Toners 2-5, 8, 10, 11)
Toners 2 to 5 were produced in the same manner as in Example 1, except that the type and amount of the external additive used were changed as shown in Table 5. Table 5 shows the evaluation results of the obtained toner.

Example 6 (Preparation of Toner 6)
5. To 100 parts by mass of toner base particles 2, hydrophobic large-diameter silica "RY50" (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: polydimethylsiloxane, particle size calculated from specific surface area: 119 nm); 4 parts by mass, and hydrophobic small particle size silica "R972" (Nippon Aerosil Co., Ltd., hydrophobic treatment agent: dimethyldichlorosilane, particle size converted from specific surface area; 25 nm) 0.5 parts by mass to Henschel mixer The mixture was added, stirred, and passed through a 150-mesh sieve to obtain Toner 6. Table 5 shows the evaluation results of Toner 6 obtained.

Example 7 (Preparation of Toner 7)
To 100 parts by mass of the toner base particles 3, hydrophobic large-diameter silica "RY50" (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: polydimethylsiloxane, particle size calculated from specific surface area: 119 nm)6. 4 parts by mass, and hydrophobic small particle size silica "R972" (Nippon Aerosil Co., Ltd., hydrophobic treatment agent: dimethyldichlorosilane, particle size converted from specific surface area; 25 nm) 0.5 parts by mass to Henschel mixer The mixture was added, stirred, and passed through a 150-mesh sieve to obtain Toner 7. Table 5 shows the evaluation results of Toner 7 obtained.

Example 9 (Preparation of Toner 9)
5. To 100 parts by mass of toner base particles 4, hydrophobic large-diameter silica "RY50" (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: polydimethylsiloxane, particle size calculated from specific surface area; 119 nm); 4 parts by mass, and hydrophobic small particle size silica "R972" (Nippon Aerosil Co., Ltd., hydrophobic treatment agent: dimethyldichlorosilane, particle size converted from specific surface area; 25 nm) 0.5 parts by mass to Henschel mixer The mixture was added, stirred, and passed through a 150-mesh sieve to obtain Toner 9. Table 5 shows the evaluation results of Toner 9 obtained.

Comparative Examples 1 and 2 (Preparation of Toners 14 and 15)
Toners 14 and 15 were produced in the same manner as in Example 1, except that the type and amount of the external additive used were changed as shown in Table 5. Table 5 shows the evaluation results of the obtained toner.

From the results of Examples and Comparative Examples, it can be seen that the use of the electrostatic image developing toner of the present invention suppresses the occurrence of fogging, and furthermore, the stability of the image density of the obtained image is high.
In Example 8, which has charged particles, fogging was suppressed more.
In Comparative Example 1, in which the mass ratio of the addition rate of the large-diameter silica particles and the small-diameter silica particles was less than 7, fogging occurred and the conveyed amount decreased. Further, in Comparative Example 2 in which the mass ratio of the addition rate exceeds 18, toner leakage occurred.

Claims (7)

To the toner base particles having a circularity of 0.965 or more,
Small-diameter silica particles having a particle size of 10 nm or more and 30 nm or less calculated from the specific surface area;
Large silica particles having a particle size of 70 nm or more and 190 nm or less converted from the specific surface area are externally added,
The mass ratio of the added amount of the large particle size silica particles and the small particle size silica particles (large particle size silica particles/small particle size silica particles) is 7 or more and 18 or less.
Toner for electrostatic charge image development. The addition amount of the small-diameter silica particles is 0.4 parts by mass or more and 1.2 parts by mass or less with respect to 100 parts by mass of the toner base particles, and the addition amount of the large-diameter silica particles is 5 parts by mass or more. 2. The toner for electrostatic charge image development according to claim 1, which is not more than parts by mass. 3. The toner for electrostatic charge image development according to claim 1, wherein the toner base particles have a circularity of 0.995 or less. 4. The toner for electrostatic charge image development according to claim 1, wherein the toner base particles contain a polyester-based resin as a binder resin. 5. The toner for electrostatic charge image development according to claim 1, wherein the toner base particles contain a crystalline polyester resin and an amorphous polyester resin A as binder resins. The amorphous polyester resin A comprises a polyester resin segment that is a polycondensate of an alcohol component and a carboxylic acid component, and an addition polymerized resin segment that is an addition polymer of a raw material monomer containing a styrene compound. 5. The toner for developing an electrostatic charge image according to 5 above. 7. The toner for electrostatic charge image development according to claim 1, wherein said small-diameter silica particles and said large-diameter silica particles are hydrophobic silica particles.