JP2016191770A - Electrostatic latent image developing toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic latent image developing toner allowing fixation at low temperature and excellent in heat resistant storage.SOLUTION: The electrostatic latent image developing toner includes toner particles including at least a binder resin, a colorant and a release agent. The binder resin includes at least a styrene acrylic resin and a crystalline polyester resin. The crystalline polyester resin is at least a polycondensate of dicarboxylic acid having a 9-18C alkyl chain and di-alcohol and satisfies formulae (1)-(3).SELECTED DRAWING: None

Description

  The present invention relates to an electrostatic latent image developing toner. More specifically, the present invention relates to a toner for developing an electrostatic latent image that can be fixed at a low temperature and has excellent heat-resistant storage properties.

  In recent years, the use of digital electrophotographic image forming apparatuses not only in office applications but also in the light printing field of the print-on-demand system (POD system) has been rapidly expanding. From such a background, reduction of heat energy at the time of fixing is required for the purpose of increasing the printing speed and reducing the environmental load. That is, electrostatic latent image developing toner (hereinafter also simply referred to as “toner”) is required to be fixed at a low temperature.

In order to achieve low-temperature fixing, basically, the glass transition point is maintained high, and the viscosity of the toner rapidly decreases at the time of heat fixing, such as crystalline polyester resin having excellent sharp melt properties. There is a method in which a resin is used for toner as a fixing aid.
For example, using a toner that is a mixture of crystalline polyester resin and styrene / acrylic resin, the crystalline part melts when the melting point of crystalline polyester exceeds the melting point of the crystalline polyester during fixing, and the crystalline polyester resin and styrene / acrylic resin are melted. Can be fixed at a low temperature (for example, see Patent Document 1).

  However, on the other hand, when the crystalline polyester resin is not sufficiently incorporated into the toner particles, the presence of the crystalline polyester resin on the surface of the toner particles can cause a halftone due to heat storage stability of the toner and a decrease in charge amount. There is a problem that transferability (HH transferability) deteriorates in reproducibility and high temperature and high humidity environment.

JP 2003-302791 A

  The present invention has been made in view of the above problems and circumstances, and a solution to that problem is to provide a toner for developing an electrostatic latent image that can be fixed at low temperature and has excellent heat-resistant storage stability. is there.

In order to solve the above-mentioned problems, the inventor controls the acid value of the styrene / acrylic resin and the crystalline polyester resin in the process of examining the cause of the above-mentioned problem, and the crystalline polyester resin in the styrene / acrylic resin is controlled. By controlling the presence state (position), it has been found that an electrostatic latent image developing toner that can be fixed at a low temperature and has excellent heat-resistant storage property can be provided.
That is, the said subject which concerns on this invention is solved by the following means.

1. An electrostatic latent image developing toner containing toner particles containing at least a binder resin, a colorant, and a release agent,
The binder resin contains at least a styrene-acrylic resin and a crystalline polyester resin;
The crystalline polyester resin is at least a polycondensate of a dicarboxylic acid having an alkyl chain with 9 to 18 carbon atoms and a dialcohol; and
An electrostatic latent image developing toner satisfying the following formulas (1) to (3):
AV (St−Ac) ≧ AV (CPEs) (1)
20 mg KOH / g ≦ AV (St-Ac) ≦ 50 mg KOH / g (2)
3 mgKOH / g ≦ ΔAV (St-Ac-CPEs) ≦ 30 mgKOH / g (3)
[In the above formulas (1) to (3), AV (St-Ac) represents the acid value of the styrene-acrylic resin. AV (CPEs) represents the acid value of the crystalline polyester resin. ΔAV (St-Ac-CPEs) represents the difference between the acid value of the styrene-acrylic resin and the crystalline polyester resin. ]

  2. 2. The electrostatic latent image developing toner according to item 1, wherein the crystalline polyester resin is a hybrid resin bonded to a resin other than the polyester resin.

  3. 3. The electrostatic latent image developing toner according to claim 2, wherein the crystalline polyester resin contains a vinyl resin as a resin other than the polyester resin.

  4). Item 4. The electrostatic latent image developing toner according to any one of Items 1 to 3, wherein the crystalline polyester resin has an acid value in a range of 10 to 40 mgKOH / g.

  5. The difference in acid value between the styrene-acrylic resin and the crystalline polyester resin is in the range of 3 to 15 mgKOH / g, Toner for developing electrostatic latent image.

  6). The electrostatic latent image according to any one of items 1 to 5, wherein a polar monomer amount of the styrene-acrylic resin is in a range of 1.0 to 10.0% by mass. Development toner.

  7). The toner for developing an electrostatic latent image according to any one of Items 1 to 6, wherein the crystalline polyester resin comprises an aliphatic dicarboxylic acid and an aliphatic dialcohol.

  8). Item 8. The electrostatic latent image developing toner according to any one of Items 1 to 7, wherein the alkyl chain of the dialcohol has a carbon number in the range of 4 to 14.

By the above means of the present invention, it is possible to provide a toner for developing an electrostatic latent image that can be fixed at a low temperature and is excellent in heat-resistant storage stability.
The expression mechanism or action mechanism of the effect of the present invention is not clear, but is presumed as follows.

When the toner is synthesized in an aqueous system, the present inventors set the acid value of the styrene / acrylic resin as the main binder higher than that of the crystalline polyester resin as the fixing aid (the above formula (1)). It was discovered that the acrylic resin tends to be oriented (existing) on the surface of the toner particles, while the crystalline polyester tends to be oriented (existing) in the center of the toner particles.
Further, by using a crystalline polyester resin comprising a dialcohol and a dicarboxylic acid having an alkyl group with 9 or more carbon atoms, the hydrophobicity of the crystalline polyester resin itself is increased, and the toner particles are more centrally located. Orientation (existence) becomes easy. If the alkyl group has more than 18 carbon atoms, the melting point of the crystalline polyester becomes high, so that the low-temperature fixability inherent in the crystalline polyester is lowered.
As a result, not only the low-temperature fixability, which is an advantage of adopting the crystalline polyester resin, is provided, but also a problem caused by the presence of the crystalline polyester resin on the surface of the toner particles (half-state caused by a decrease in the charge amount). Toner having reduced tone reproducibility and HH transferability, heat resistance storage deterioration, etc.) can be obtained.

  In addition, when a styrene / acrylic resin is used as compared with the case where an amorphous polyester resin is used as the binder resin, a high image density and a good HH transferability can be secured. The reason for this is not clear, but styrene / acrylic resin has higher affinity with the colorant than amorphous polyester resin, so dispersibility can be secured even if the colorant is highly charged in the resin. I guess.

The acid value (AV (St-Ac)) of the styrene-acrylic resin is in the range of 20 to 50 mgKOH / g (the above formula (2)), more preferably in the range of 25 to 45 mgKOH / g, and still more preferably. Is in the range of 30-40 mg KOH / g.
When it is lower than the lower limit in the above formula (2) (when AV (St-Ac) <20 mgKOH / g), the dispersion state of the colorant deteriorates.
Further, when it is higher than the upper limit in the above formula (2) (when AV (St-Ac)> 50 mgKOH / g), the low-temperature fixability deteriorates.

The acid value (AV (St-Ac)) of the styrene-acrylic resin is larger than the acid value (AV (CPEs)) of the crystalline polyester resin (formula (1)).
Furthermore, the acid value difference (ΔAV (St-Ac-CPEs)) between the styrene / acrylic resin and the crystalline polyester resin is in the range of 3 to 30 mgKOH / g (formula (3)), and preferably 3 to 25 mgKOH / g. 3-15 mg KOH / g is more preferable.

When smaller than the lower limit in the above formula (3) (ΔAV (St-Ac-CPEs) <3 mgKOH / g), the crystalline polyester resin tends to be present on the surface of the toner particles, resulting in deterioration of heat-resistant storage property and decrease in charge. .
On the other hand, when it is larger than the upper limit in the above formula (3) (ΔAV (St-Ac-CPEs)> 30 mgKOH / g), it becomes difficult to emulsify the crystalline polyester resin, or the low-temperature fixability is deteriorated.

  The electrostatic latent image developing toner of the present invention is an electrostatic latent image developing toner containing toner particles containing at least a binder resin, a colorant and a release agent, wherein the binder resin is at least styrene. An acrylic resin and a crystalline polyester resin are contained, and the crystalline polyester resin is a polycondensate of at least an alkyl chain having a carbon number of 9 to 18 with a dialcohol, and the above It is characterized by satisfy | filling Formula (1)-(3). This feature is a technical feature common to the inventions according to claims 1 to 8.

  As an embodiment of the present invention, the crystalline polyester resin is preferably a hybrid resin bonded to a resin other than the polyester resin. Further, as the resin other than the polyester resin, it is particularly preferable to contain a vinyl-based resin because the dispersion state of the crystalline polyester can be satisfactorily maintained in the styrene / acrylic resin as the main binder.

  In the present invention, the acid value of the crystalline polyester resin is preferably in the range of 10 to 40 mgKOH / g. If it is in this range, emulsification of the crystalline polyester resin will not be difficult. Further, if it is within this range, it is possible to suppress the presence of the crystalline polyester resin on the surface of the toner particles, and in the toner, it is possible to suppress deterioration in heat-resistant storage property and charge reduction.

  In the present invention, the difference in acid value between the styrene / acrylic resin and the crystalline polyester resin (ΔAV (St-Ac-CPEs)) is preferably in the range of 3 to 15 mgKOH / g. Furthermore, deterioration of heat-resistant storage stability and charge reduction can be suppressed, and it can be avoided that emulsification of the crystalline polyester resin becomes difficult or deterioration of low-temperature fixability is caused.

  In the present invention, the amount of the polar monomer of the styrene / acrylic resin is preferably in the range of 1.0 to 10.0% by mass because it is possible to prevent the dispersion of the colorant and the low-temperature fixability from being deteriorated.

  In the present invention, it is easier for the crystalline polyester resin to be composed of an aliphatic dicarboxylic acid and an aliphatic dialcohol in the central part of the toner particles, and as a result, the heat resistant storage stability of the toner and the half of the toner amount are reduced. This is preferable because deterioration of tone reproducibility and HH transferability can be further suppressed.

  In the present invention, the number of carbon atoms in the alkyl chain of the dialcohol is in the range of 4 to 14 can ensure low-temperature fixability, and more easily a crystalline polyester resin is present at the center of the toner particles. Therefore, it is preferable because the heat-resistant storage stability of the toner and the halftone reproducibility and HH transferability due to a decrease in charge amount can be further suppressed.

  Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In addition, in this application, "-" is used in the meaning which includes the numerical value described before and behind that as a lower limit and an upper limit.

<Overview of electrostatic latent image developing toner>
The electrostatic latent image developing toner of the present invention is an electrostatic latent image developing toner containing toner particles containing at least a binder resin, a colorant and a release agent, wherein the binder resin is at least styrene. An acrylic resin and a crystalline polyester resin are contained, and the crystalline polyester resin is a polycondensate of at least an alkyl chain having a carbon number of 9 to 18 with a dialcohol, and the above It is characterized by satisfy | filling Formula (1)-(3).

[Toner particles]
The toner particles according to the present invention are preferably those obtained by adding an external additive to the toner base particles.
The “toner base particle” is a particle containing at least a binder resin and a colorant. The toner base particles can be used as toner particles according to the present invention without any external additives.

The average particle size of the toner particles of the present invention is 3.0 to 8.0 μm, preferably 4.0 to 7.5 μm in terms of volume average particle size. By being in the above range, it is possible to suppress flying and adhering to the heating member at the time of fixing, so that toner particles having a large adhesion force that generate a fixing offset are reduced.
Further, when the volume average particle size is within the above range, the transfer efficiency is increased and the image quality of halftone is improved, and as a result, the image quality of fine lines and dots is improved.
In addition, toner fluidity can be secured.

The average particle size of the toner particles can be controlled by the concentration of the aggregating agent, the amount of the solvent added or the fusing time in the agglomeration and fusing step during the production of the toner particles, and the composition of the binder resin.
The toner particles according to the present invention have an average circularity of 0.920 to 1 from the viewpoint of improving transfer efficiency.
. 000 is preferred.
The average circularity can be measured using, for example, an average circularity measuring device “FPIA-2100” (manufactured by Sysmex).

  The volume average particle diameter of the toner particles was determined by connecting a computer system (Beckman Coulter, Inc.) equipped with data processing software “Software V3.51” to “Multisizer 3 (Beckman Coulter, Inc.)”. It can be measured and calculated using an apparatus.

As a measurement procedure, 0.02 g of toner particles are added with 20 mL of a surfactant solution (for example, a surfactant solution obtained by diluting a neutral detergent containing a surfactant component 10 times with pure water for the purpose of dispersing toner particles). After acclimation, ultrasonic dispersion is performed for 1 minute to prepare a toner particle dispersion. This toner particle dispersion is poured into a beaker containing ISOTON II (manufactured by Beckman Coulter) in a sample stand with a pipette until the measured concentration becomes 5 to 10%, and the measuring machine count is set to 25,000. taking measurement. The aperture size of the multisizer 3 is 100 μm. The frequency number obtained by dividing the measurement range of 2 to 60 μm into 256 parts is calculated, and the particle diameter of 50% from the larger volume integrated fraction is defined as the volume average particle diameter.
The particle size of the toner base particles can be measured in the same manner.

[Binder resin]
The binder resin according to the present invention contains at least a styrene / acrylic resin (amorphous resin) and a crystalline polyester resin.
The binder resin according to the present invention may also contain an amorphous resin other than styrene / acrylic resin.

<Styrene acrylic resin>
The polar monomer amount of the styrene / acrylic resin is preferably in the range of 1.0 to 10.0% by mass, more preferably 1.0 to 9.0% by mass, and still more preferably 3.0 to 9.%. It is in the range of 0% by mass. When the content is 1.0% by mass or more, the dispersion of the colorant is not deteriorated, and when the content is 10.0% by mass or less, the low-temperature fixability is not deteriorated.

(Polar monomer amount of styrene / acrylic resin)
The amount of polar monomer of styrene / acrylic resin represents the amount occupied by components derived from acrylic acid or methacrylic acid with respect to the entire styrene / acrylic resin, and the amount of acrylic acid or methacrylic acid used to synthesize styrene / acrylic resin. Controlled by the amount charged.

<Amorphous resin other than styrene / acrylic resin>
The amorphous resin other than the styrene / acrylic resin that can be contained in the binder resin according to the present invention is not particularly limited, but is preferably a vinyl resin, a urethane resin, a urea resin, a polyester resin, or the like.

(Vinyl resin)
When a vinyl resin is used as the amorphous resin, the vinyl resin is not particularly limited as long as a vinyl compound is polymerized. For example, acrylate resin, styrene / acrylate resin, ethylene / vinyl acetate resin, etc. Is mentioned. These may be used individually by 1 type and may be used in combination of 2 or more type.
Among the vinyl resins described above, styrene / acrylic acid ester resins (styrene / acrylic resins) are preferable in view of plasticity during heat fixing.
Therefore, although detailed description is omitted, as the styrene monomer, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-phenylstyrene, p-ethylstyrene; ) Acrylic acid ester monomers such as methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, etc .; methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, isobutyl methacrylate It is preferable to use methacrylic acid esters such as These styrene monomers and (meth) acrylic acid ester monomers can be used alone or in combination of two or more.
Further, other monomers may be polymerized, and examples thereof include acrylic acid, methacrylic acid, maleic acid, itaconic acid, cinnamic acid, fumaric acid, maleic acid monoalkyl ester, and itaconic acid monoester. Alkyl ester, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4- Examples thereof include hydroxybutyl (meth) acrylate and polyethylene glycol mono (meth) acrylate.
The method for producing the styrene / acrylic resin is not particularly limited, and can be produced by an emulsion polymerization method or the like.

<Crystalline polyester resin>
The crystalline polyester resin refers to a polyester resin having a clear endothermic peak instead of a stepwise endothermic change in differential scanning calorimetry (DSC). The clear endothermic peak specifically means a peak in which the half-value width of the endothermic peak is within 15 ° C. when measured at a rate of temperature increase of 10 ° C./min in differential scanning calorimetry (DSC). To do. Note that the smaller the half width, the higher the crystallinity.

  The acid value of the crystalline polyester resin is preferably in the range of 10 to 40 mgKOH / g, more preferably in the range of 15 to 35 mgKOH / g, and still more preferably in the range of 15 to 30 mgKOH / g. If it is in this range, emulsification of the crystalline polyester resin will not be difficult. Further, if it is within this range, it is possible to suppress the presence of the crystalline polyester resin on the surface of the toner particles, and in the toner, it is possible to suppress deterioration in heat-resistant storage property and charge reduction.

In addition, as a specific method of differential scanning calorimetry of the toner, “Diamond DSC” (manufactured by Perkin Elmer) was used, the temperature was raised from room temperature to 150 ° C. at a raising / lowering rate of 10 ° C./min, and at 150 ° C. for 5 minutes. The first temperature rising process for isothermal holding, the cooling process from 150 ° C. to 0 ° C. at a cooling rate of 10 ° C./min, and the isothermal holding process for 5 minutes at 0 ° C. It is mentioned that the second temperature raising process for raising the temperature is performed under measurement conditions (temperature raising / cooling conditions) in this order.
As a measurement procedure, 3.0 mg of toner may be sealed in an aluminum pan and set in a “diamond DSC” sample holder. The reference uses an empty aluminum pan.

  The crystalline polyester resin according to the present invention is a polycondensate of a dicarboxylic acid (polyhydric carboxylic acid) having an alkyl chain in the range of 9 to 18 carbon atoms and a dialcohol (polyhydric alcohol). The expressions (1) to (3) are satisfied.

AV (St−Ac) ≧ AV (CPEs) (1)
20 mg KOH / g ≦ AV (St-Ac) ≦ 50 mg KOH / g (2)
3 mgKOH / g ≦ ΔAV (St-Ac-CPEs) ≦ 30 mgKOH / g (3)

[In the above formulas (1) to (3), AV (St-Ac) represents the acid value of the styrene-acrylic resin. AV (CPEs) represents the acid value of the crystalline polyester resin. ΔAV (St-Ac-CPEs) represents the difference between the acid value of the styrene-acrylic resin and the crystalline polyester resin. ]

  In addition, when it is lower than the lower limit in the above formula (2) (when AV (St-Ac) <20 mgKOH / g), the dispersion state of the colorant is deteriorated. Further, when it is higher than the upper limit in the above formula (2) (when AV (St-Ac)> 50 mgKOH / g), the low-temperature fixability deteriorates.

  When smaller than the lower limit in the above formula (3) (ΔAV (St-Ac-CPEs) <3 mgKOH / g), the crystalline polyester resin tends to be present on the surface of the toner particles, resulting in deterioration of heat-resistant storage property and decrease in charge. . On the other hand, when it is larger than the upper limit in the above formula (3) (ΔAV (St-Ac-CPEs)> 30 mgKOH / g), it becomes difficult to emulsify the crystalline polyester resin, or the low-temperature fixability is deteriorated.

The crystalline polyester resin according to the present invention is not particularly limited as long as it satisfies the above definition, and may contain other resins as long as the effects of the present invention are not inhibited.
That is, the crystalline polyester resin according to the present invention may be a crystalline polyester resin itself or a hybrid resin having a crystalline polyester resin unit.

  Although details will be described later, as a hybrid resin, a resin having a structure in which other components are copolymerized with a main chain of a crystalline polyester resin unit, or a crystalline polyester resin unit is copolymerized with a main chain composed of other components. It may be a resin having a structure. If the toner containing such a hybrid resin exhibits a clear endothermic peak as described above, it can be suitably used as the crystalline polyester resin of the present invention.

  The crystalline polyester resin according to the present invention is produced from dicarboxylic acid (polyhydric carboxylic acid) and dialcohol (polyhydric alcohol).

The crystalline polyester resin is preferably composed of an aliphatic dicarboxylic acid and an aliphatic dialcohol. The aliphatic dialcohol preferably has 2 or more carbon atoms.
By satisfying these conditions, the crystalline polyester resin is more likely to be present in the center part of the toner particles, and as a result, the heat-resistant storage stability of the toner and the halftone reproducibility and HH transferability are further deteriorated due to a decrease in charge amount. Can be suppressed.
The aliphatic dicarboxylic acid is a monomer that can be a raw material of the polyester resin, and has a carboxy group at both ends of the linear alkyl group.
An aliphatic dialcohol is a monomer that can be a raw material for a polyester resin, and has hydroxy groups at both ends of a linear alkyl group.

Moreover, it is preferable that the acid value (AV) of crystalline polyester resin exists in the range of 10-40 mgKOH / g.
If it is in this range, emulsification of the crystalline polyester resin will not be difficult. Further, if it is within this range, it is possible to suppress the presence of the crystalline polyester resin on the surface of the toner particles, and it is possible to suppress the deterioration of the heat-resistant storage property of the toner and the decrease in charge.

  The difference in acid value between the styrene / acrylic resin and the crystalline polyester resin (ΔAV (St-Ac-CPEs)) is in the range of 3 to 15 mgKOH / g. It is preferable because the properties can be further improved.

(Dicarboxylic acid having an alkyl chain having 9 to 18 carbon atoms)
The dicarboxylic acid having an alkyl chain of 9 to 18 carbon atoms of the present invention is particularly preferably a linear alkyl chain having no branching.

Examples of the dicarboxylic acid constituting the crystalline polyester resin include aliphatic dicarboxylic acids having 9 to 18 carbon atoms in the alkyl chain. By using an aliphatic dicarboxylic acid having 9 or more carbon atoms, the hydrophobicity of the crystalline polyester resin itself becomes high, and it becomes easier to exist in the center of the toner particles.
Moreover, low temperature fixability can be realized by using an aliphatic carboxylic acid having 18 or less carbon atoms.

In addition to the aliphatic dicarboxylic acid, an aromatic dicarboxylic acid may be used in combination.
In addition, as aliphatic dicarboxylic acid, it is preferable to use a linear type as described above because crystallinity is improved.
In addition, dicarboxylic acid employable for this invention is not limited to one type, You may mix and use 2 or more types.

(Aliphatic dicarboxylic acid)
Examples of the aliphatic dicarboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid (undecanedioic acid), 1 , 10-decanedicarboxylic acid (dodecanedioic acid), 1,11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid (tetradecanedioic acid), 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, cyclohexanedicarboxylic acid and the like can be mentioned, and lower alkyl esters and acid anhydrides thereof can also be used.

(Aromatic dicarboxylic acid)
Examples of the aromatic dicarboxylic acid that can be used with the aliphatic dicarboxylic acid include terephthalic acid, isophthalic acid, orthophthalic acid, t-butylisophthalic acid, 2,6-naphthalenedicarboxylic acid, and 4,4′-biphenyldicarboxylic acid. Is mentioned. Among these, terephthalic acid, isophthalic acid, and t-butylisophthalic acid are preferably used from the viewpoints of availability and emulsification ease.

  As the dicarboxylic acid for forming the crystalline polyester resin (or crystalline polyester resin unit described later), the content of the aliphatic dicarboxylic acid is preferably 50 constituent mol% or more, more preferably 70 constituent mol. % Or more, more preferably 80 constituent mol% or more, and particularly preferably 100 constituent mol%. When the content of the aliphatic dicarboxylic acid in the dicarboxylic acid for forming the crystalline polyester resin (or the crystalline polyester resin unit described later) is 50 constituent mol% or more, the crystalline polyester resin (or the crystal described later) Sufficient crystallinity of the conductive polyester resin unit).

(Dialcohol)
The carbon number of the alkyl chain of the dialcohol is within the range of 4 to 14 to ensure low-temperature fixability and more easily exist in the center of the toner particles, and as a result, the heat storage stability of the toner and the charge amount decrease. This is preferable since the deterioration of halftone reproducibility and HH transferability can be further suppressed.

As the dialcohol (diol), it is preferable to use an aliphatic diol,
You may contain diols other than aliphatic diol as needed. As the aliphatic diol, a linear diol is preferably used. Of these, aliphatic diols having 4 or more carbon atoms in the main chain are preferred.
In addition, there exists an advantage that crystallinity improves by using a linear type thing. A dialcohol may be used individually by 1 type and may be used 2 or more types.

  Specific examples of the dialcohol constituting the crystalline polyester resin include ethylene glycol, 1,2-propanediol, 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 Aliphatic diols such as tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol, neopentyl glycol, 1,4-butenediol can be suitably used. Among them, aliphatic diols having 4 or more carbon atoms in the main chain are preferable. Specifically, butanediol (carbon number 4), pentanediol (carbon number 5), hexanediol (carbon number 6), heptanediol (carbon number) 7), octanediol (carbon number 8), nonanediol (carbon number 9), decanediol (carbon number 10), undecanediol (carbon number 11), dodecanediol (carbon number 12), tridecanediol (carbon number 13) ), Tetradecanediol (carbon number 14) and the like are preferable.

  In addition, a trihydric or higher polyhydric alcohol such as glycerin, pentaerythritol, trimethylolpropane, or sorbitol may be used in combination as long as the effect of the present invention is not inhibited.

  Examples of the diol other than the above-mentioned aliphatic diol preferably used in the present invention include a diol having a double bond, a diol having a sulfonic acid group, and the like. Specifically, as the diol having a double bond, Examples thereof include 2-butene-1,4-diol, 3-butene-1,6-diol, 4-butene-1,8-diol, and the like.

In addition, as a diol for forming a crystalline polyester resin (or a crystalline polyester resin unit described later), the content of the aliphatic diol is preferably 50 constituent mol% or more in the diol, more preferably It is 70 component mol% or more, More preferably, it is 80 component mol% or more, Most preferably, it is 100 component mol%.
When the content of the aliphatic diol in the diol for forming the crystalline polyester resin (or the crystalline polyester resin unit described later) is 50 constituent mol% or more, the crystalline polyester resin (or the crystalline polyester described later) is obtained. The crystallinity of the resin unit) can be ensured, and excellent low-temperature fixability can be obtained for the produced toner, and glossiness can be obtained for the finally formed image.

  The method for forming the crystalline polyester resin is not particularly limited, and the resin can be formed by polycondensation (esterification) of the dicarboxylic acid and dialcohol using a known esterification catalyst.

  When polymerizing the crystalline polyester resin, the use ratio of the dialcohol and the dicarboxylic acid is equivalent to the equivalent ratio [OH] / [COOH] of the hydroxy group [OH] of the diol and the carboxy group [COOH] of the dicarboxylic acid. Is preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2.

Catalysts that can be used in the formation of the crystalline polyester resin include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; aluminum, zinc, manganese, antimony, titanium, tin, zirconium, Examples thereof include metal compounds such as germanium; phosphorous acid compounds; phosphoric acid compounds; and amine compounds. Specifically, examples of the tin compound include dibutyltin oxide, tin octylate, tin dioctylate, and salts thereof. Titanium compounds include titanium alkoxides such as tetranormal butyl titanate, tetraisopropyl titanate, tetramethyl titanate, and tetrastearyl titanate; titanium acylates such as polyhydroxy titanium stearate; titanium tetraacetylacetonate, titanium lactate, titanium triethanolamine Examples thereof include titanium chelates such as nates. Examples of germanium compounds include germanium dioxide. Furthermore, as an aluminum compound, oxides, such as poly aluminum hydroxide, aluminum alkoxide, etc. are mentioned, A tributyl aluminate etc. can be mentioned. You may use these individually by 1 type or in combination of 2 or more types.
The polymerization temperature and the polymerization time are not particularly limited, and the inside of the reaction system may be depressurized as necessary during the polymerization.

  In addition, as a method for isolating / extracting the crystalline polyester resin from the toner, for example, a method described in Japanese Patent No. 3869968 can be adopted, and thereby the content ratio can be specified. Moreover, the structural component and content rate of a hybrid crystalline polyester resin and a hybrid amorphous resin can be specified by, for example, NMR measurement and methylation reaction P-GC / MS measurement.

<Hybrid resin>
The crystalline polyester resin may be a hybrid resin (hybrid crystalline polyester resin) bonded to a resin other than the polyester resin.
Specifically, the hybrid crystalline polyester resin (hereinafter, also referred to as “hybrid resin”) includes a resin including an amorphous resin unit other than the polyester resin described in detail below, in addition to the crystalline polyester resin. It is. The crystalline polyester resin unit refers to a portion derived from a crystalline polyester resin, and the amorphous resin unit other than the crystalline polyester resin refers to a portion derived from an amorphous resin other than polyester.
The hybrid resin may be in any form such as a block copolymer or a graft copolymer as long as it includes the crystalline polyester resin unit and an amorphous resin unit other than the polyester resin. A coalescence is preferable. By using the graft copolymer, it becomes easy to control the intramolecular orientation of the crystalline polyester resin unit, and sufficient crystallinity can be imparted to the hybrid resin.

  The form of the hybrid crystalline polyester resin may be any form as long as the crystalline polyester resin unit and the amorphous resin unit other than the polyester resin are combined. From the above viewpoint, the crystalline polyester resin unit is It is preferable that an amorphous resin unit other than the polyester resin is grafted as a main chain. That is, the hybrid crystalline polyester resin is preferably a graft copolymer having an amorphous resin unit other than the polyester resin as a main chain and a crystalline polyester resin unit as a side chain.

By setting it as the said form, the orientation of a crystalline polyester resin unit can be raised more, and the crystallinity of hybrid resin can be improved.
In addition, substituents, such as a sulfonic acid group, a carboxy group, and a urethane group, may be further introduced into the hybrid resin. The introduction of the substituent may be in the crystalline polyester resin unit or in an amorphous resin unit other than the polyester resin described in detail below.

  The content of the crystalline polyester resin unit in the hybrid resin is preferably 50% by mass or more and less than 98% by mass with respect to the total amount of the hybrid resin. By setting it as the above range, sufficient crystallinity can be imparted to the hybrid resin. In addition, the structural component and content rate of each unit in a hybrid resin can be specified by NMR measurement and methylation reaction P-GC / MS measurement, for example.

  When the crystalline polyester resin according to the present invention is a hybrid crystalline polyester resin including units of resins other than the polyester resin described below, the proportion of the hybrid crystalline polyester resin in the entire binder resin is 10 to 50% by mass. It is preferable that it is 10-25 mass%.

(Resin other than polyester resin)
The resin other than the polyester resin is preferably a portion derived from an amorphous resin other than the polyester resin (hereinafter also referred to as “amorphous resin unit”). It is suitable from the NMR measurement, P-GC / MS measurement, methylation reaction P-GC / MS measurement and the like that the amorphous resin unit is contained in the hybrid resin (and further in the toner particles) depending on the structure. Analytical methods can be selected and the chemical structure can be characterized.

  Note that the amorphous resin unit means that a resin having the same chemical structure and molecular weight as the unit has a relatively high glass transition temperature (Tg) without a melting point when differential scanning calorimetry (DSC) is performed. It is a resin unit.

  The amorphous resin unit is not particularly limited as long as it is defined above. For example, for a resin having a structure in which other components are copolymerized on the main chain of an amorphous resin unit and a resin having a structure in which an amorphous resin unit is copolymerized on a main chain composed of other components, this resin is used. If the toner to be contained has an amorphous resin unit as described above, the resin corresponds to the hybrid resin having an amorphous resin unit in the present invention.

  The amorphous resin unit is preferably composed of the same kind of resin as the amorphous resin (that is, a resin other than the hybrid resin) contained in the binder resin. By adopting such a form, the affinity between the hybrid resin and the amorphous resin is further improved, the hybrid resin is more easily taken into the amorphous resin, and the charging uniformity and the like are further improved.

  Here, “the same kind of resin” means that a characteristic chemical bond is commonly contained in the repeating unit. The “characteristic chemical bond” is described in the National Institute for Materials Science (NIMS) Substance / Material Database (http://polymer.nims.go.jp/PoLyInfo/guide/jp/term_polymer.html). Follow “Polymer classification”. That is, polyacryl, polyamide, polyanhydride, polycarbonate, polydiene, polyester, polyhaloolefin, polyimide, polyimine, polyketone, polyolefin, polyether, polyphenylene, polyphosphazene, polysiloxane, polystyrene, polysulfide, polysulfone, polyurethane, polyurea Chemical bonds constituting polymers classified according to a total of 22 types of polyvinyl and other polymers are referred to as “characteristic chemical bonds”.

  In the case where the resin is a copolymer, the “same kind of resin” means a characteristic in the case where the monomer type having the above chemical bond is used as a constituent unit in the chemical structure of a plurality of monomer types constituting the copolymer. Refers to resins having common chemical bonds. Therefore, even if the characteristics of the resin itself are different from each other, or even when the molar component ratios of the monomer species constituting the copolymer are different from each other, the same type of chemical bonds are used as long as they have a common chemical bond Considered resin.

  For example, a resin (or resin unit) formed from styrene, butyl acrylate and acrylic acid and a resin (or resin unit) formed from styrene, butyl acrylate and methacrylic acid have at least chemical bonds constituting polyacryl. These are the same kind of resins. To further illustrate, a resin (or resin unit) formed of styrene, butyl acrylate and acrylic acid and a resin (or resin unit) formed of styrene, butyl acrylate, acrylic acid, terephthalic acid and fumaric acid are mutually As a common chemical bond, it has a chemical bond constituting at least polyacryl. Therefore, these are the same kind of resins.

  The resin component constituting the amorphous resin unit is not particularly limited, and examples thereof include vinyl resins such as styrene / acrylic resins, urethane resins, urea resins, etc., but amorphous resins constituting the toner. It is preferable that the same type of resin unit. Of these, vinyl resins, particularly styrene / acrylic resins, are preferable because the thermoplasticity is easily controlled.

  The vinyl resin unit is not particularly limited as long as a vinyl compound is polymerized, and examples thereof include an acrylic ester resin unit, a styrene / acrylic ester resin unit, and an ethylene / vinyl acetate resin unit. These may be used individually by 1 type and may be used in combination of 2 or more type.

  The method for forming the styrene / acrylic resin unit is not particularly limited, and examples thereof include a method of polymerizing a monomer using a known oil-soluble or water-soluble polymerization initiator. Specific examples of the oil-soluble polymerization initiator include the following azo or diazo polymerization initiators and peroxide polymerization initiators.

  The said resin unit may be used individually by 1 type, and may be used in combination of 2 or more type. Although it is content of resin (for example, amorphous resin unit) other than polyester resin, it is preferable in it being in the range of 0.1-50 mass% with respect to the whole quantity of hybrid resin. Furthermore, the content is more preferably in the range of 1 to 50% by mass, and most preferably in the range of 3 to 40% by mass. By setting it as the above range, sufficient crystallinity can be imparted to the hybrid resin.

(Polymerization initiator)
As the azo or diazo polymerization initiator, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1) -Carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile and the like.

  As the peroxide polymerization initiator, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, 2,4 -Dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis- (4,4-t-butylperoxycyclohexyl) propane, tris- (t-butylperoxy) triazine and the like.

  Moreover, when forming resin particles by an emulsion polymerization method, a water-soluble radical polymerization initiator can be used. Examples of the water-soluble polymerization initiator include persulfates such as potassium persulfate and ammonium persulfate, azobisaminodipropane acetate, azobiscyanovaleric acid and its salts, hydrogen peroxide, and the like.

<Method for producing hybrid crystalline polyester resin (hybrid resin)>
In the method for producing a hybrid resin contained in the binder resin according to the present invention, a polymer having a structure in which the crystalline polyester resin unit and the amorphous resin unit (resin other than the polyester resin) are molecularly bonded is formed. As long as the method is possible, there is no particular limitation. Specific examples of the method for producing the hybrid resin include the following methods.

(1) A method of producing a hybrid resin by polymerizing an amorphous resin unit in advance and performing a polymerization reaction to form a crystalline polyester resin unit in the presence of the amorphous resin unit. An amorphous resin unit is formed by addition reaction of the monomer constituting the above-described amorphous resin unit (preferably, a styrene monomer and a vinyl monomer such as a (meth) acrylate monomer). . Next, in the presence of the amorphous resin unit, a dicarboxylic acid and a dialcohol are polymerized to form a crystalline polyester resin unit. At this time, the dicarboxylic acid and dialcohol are subjected to a condensation reaction, and a hybrid resin is formed by addition reaction of the dicarboxylic acid or dialcohol to the amorphous resin unit.

In the above method, it is preferable to incorporate a site where these units can react with each other in the crystalline polyester resin unit or the amorphous resin unit. Specifically, when the amorphous resin unit is formed, the carboxy group [—COOH] or the hydroxy group [—OH] remaining in the crystalline polyester resin unit in addition to the monomer constituting the amorphous resin unit. A compound having a site capable of reacting with an amorphous resin unit and a site capable of reacting with an amorphous resin unit is also used. That is, when this compound reacts with a carboxy group [—COOH] or a hydroxy group [—OH] in the crystalline polyester resin unit, the crystalline polyester resin unit can be chemically bonded to the amorphous resin unit. it can.
In addition, a compound having a site capable of reacting with a dialcohol or dicarboxylic acid and capable of reacting with an amorphous resin unit may be used during the formation of the crystalline polyester resin unit.
By using the above method, a hybrid resin having a structure (graft structure) in which a crystalline polyester resin unit is molecularly bonded to an amorphous resin unit can be formed.

(2) A method of producing a hybrid resin by forming a crystalline polyester resin unit and an amorphous resin unit and bonding them together. In this method, first, a dicarboxylic acid and a dialcohol are subjected to a condensation reaction. A crystalline polyester resin unit is formed. In addition to the reaction system for forming the crystalline polyester resin unit, the monomer constituting the above-described amorphous resin unit is subjected to addition polymerization to form the amorphous resin unit. At this time, it is preferable to incorporate a site where the crystalline polyester resin unit and the amorphous resin unit can react with each other. In addition, since the method of incorporating such a reactive site is as described above, detailed description thereof is omitted.
Next, a hybrid resin having a structure in which the crystalline polyester resin unit and the amorphous resin unit are molecularly bonded can be formed by reacting the crystalline polyester unit formed above with the amorphous resin unit. it can.

  In addition, when the reactive site is not incorporated in the crystalline polyester resin unit and the amorphous resin unit, a system in which the crystalline polyester resin unit and the amorphous resin unit coexist is formed, You may employ | adopt the method of throwing in the compound which has a site | part which can couple | bond with a crystalline polyester resin unit and an amorphous resin unit. A hybrid resin having a structure in which a crystalline polyester resin unit and an amorphous resin unit are molecularly bonded can be formed via the compound.

(3) A method of producing a hybrid resin by forming a crystalline polyester resin unit in advance and performing a polymerization reaction to form an amorphous resin unit in the presence of the crystalline polyester resin unit. Polymerization is carried out by subjecting a dicarboxylic acid and a dialcohol to a condensation reaction to form a crystalline polyester resin unit. Next, in the presence of the crystalline polyester resin unit, a monomer constituting the amorphous resin unit is polymerized to form an amorphous resin unit. At this time, similarly to the above (1), it is preferable to incorporate a site where these units can react with each other in the crystalline polyester resin unit or the amorphous resin unit. In addition, since the method of incorporating such a reactive site is as described above, detailed description thereof is omitted.

  By using the above method, a hybrid resin having a structure (graft structure) in which an amorphous resin unit is molecularly bonded to a crystalline polyester resin unit can be formed.

Among the forming methods (1) to (3), the method (1) is easy to form a hybrid resin having a structure in which a crystalline polyester resin chain is grafted to an amorphous resin chain, and a production process. Is preferable because it can be simplified.
In the method (1), since the crystalline polyester resin unit is bonded after the amorphous resin unit is formed in advance, the orientation of the crystalline polyester resin unit tends to be uniform. Therefore, it is preferable because a hybrid resin suitable for the toner specified in the present invention can be reliably formed.

<Measurement method of acid value (AV)>
The acid value is the mass of potassium hydroxide (KOH) required to neutralize the acid contained in 1 g of resin, expressed in mg. The acid value of the resin is measured according to JIS K0070-1966. Specifically, it is measured according to the following procedure.

(1. Preparation of reagents)
Dissolve 1.0 g of phenolphthalein in 90 mL of ethyl alcohol (95% by volume), add ion-exchanged water to make 100 mL, and prepare a “phenolphthalein solution”. 7 g of JIS special grade potassium hydroxide is dissolved in 5 mL of ion exchange water, and ethyl alcohol (95% by volume) is added to make 1 liter. In order to avoid contact with carbon dioxide gas, it is placed in an alkali-resistant container and allowed to stand for 3 days, followed by filtration to produce a “potassium hydroxide solution”. The orientation is in accordance with the description of JIS K0070-1966.

(2. Operation)
(2.a) Main test 2.0 g of the pulverized resin sample is precisely weighed into a 200 mL Erlenmeyer flask, and 100 mL of a mixed solution of toluene / ethanol (2: 1) is added and dissolved over 5 hours. Subsequently, several drops of the phenolphthalein solution is added as an indicator, and titration is performed using the potassium hydroxide solution. Note that the end point of the titration is when the light red color of the indicator lasts for about 30 seconds.

(2.b) Blank test The same operation as described above is performed except that no sample is used (that is, only a mixed solution of toluene / ethanol (2: 1) is used).

(3) Calculation of acid value The obtained result is substituted into the following formula (A) to calculate the acid value.
Formula (A): A = [(BC) × f × 5.6] / S

here,
A: Acid value (mgKOH / g),
B: Amount of added potassium hydroxide solution for blank test (mL),
C: Amount of addition (mL) of potassium hydroxide solution in this test,
f: Factor of 0.1 mol / liter potassium hydroxide ethanol solution,
S: Sample (g).

[Colorant]
As the colorant that can constitute the toner, carbon black, magnetic material, dye, pigment, etc. can be used arbitrarily. As the carbon black, channel black, furnace black, acetylene black, thermal black, lamp black, etc. are used. Is done. Magnetic materials include ferromagnetic metals such as iron, nickel and cobalt, alloys containing these metals, compounds of ferromagnetic metals such as ferrite and magnetite, alloys that do not contain ferromagnetic metals but exhibit ferromagnetism by heat treatment, For example, a kind of alloy called Heusler alloy such as manganese-copper-aluminum and manganese-copper-tin, chromium dioxide, and the like can be used.

  Examples of the colorant for magenta or red include C.I. I. Pigment Red 2, 3, 5, 6, 7, 15, 16, 48: 1, 48: 3, 53: 1, 57: 1, 60, 63, 64 68, 81, 81: 4, 83, 87, 88, 89, 90, 112, 114, 122, 123, 139, 144, 149, 150 163, 166, 170, 177, 178, 184, 202, 206, 207, 209, 222, 238, 269, and the like.

Examples of the colorant for orange or yellow include C.I. I. Pigment Orange 31 and 43, C.I. I. Pigment Yellow 12, 14, 15, 17, 74, 83, 93, 94, 138, 139, 155, 162, 180, 185, C.I. I. Solvent yellow 93 etc. are mentioned.
Further, examples of the colorant for green or cyan include C.I. I. Pigment Blue 2, 3, 15, 15, 15: 2, 15: 3, 15: 4, 16, 17, 17, 60, 62, 66, C.I. I. And CI Pigment Green 7.
These colorants can be used alone or in combination of two or more as required.

The addition amount of the colorant is preferably 1 to 30% by mass, more preferably 2 to 20% by mass with respect to the whole toner, and a mixture thereof can also be used. Within such a range, the color reproducibility of the image can be ensured.
Further, the colorant dispersion diameter in the toner is preferably 10 to 1000 nm, 50 to 500 nm, and more preferably 80 to 300 nm in terms of volume average particle diameter.

[Release agent]
The release agent constituting the toner is not particularly limited, and known ones can be used. Specifically, for example, polyolefin wax such as polyethylene wax and polypropylene wax, branched chain hydrocarbon wax such as microcrystalline wax, long chain hydrocarbon wax such as paraffin wax and sazol wax, distearyl ketone, etc. Dialkyl ketone wax, carnauba wax, montan wax, behenate behenate, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerol tribehenate, 1,18-octadecane Ester wax such as diol distearate, tristearyl trimellitic acid, distearyl maleate, ethylenediamine behenyl amide, tristearyl amide of trimellitic acid And the like amide-based waxes such as.

  Melting | fusing point of a mold release agent becomes like this. Preferably it is 40-160 degreeC, More preferably, it is 50-120 degreeC. By setting the melting point within the above range, the heat-resistant storage stability of the toner is ensured, and stable toner image formation can be performed without causing cold offset or the like even when fixing at a low temperature. Further, the content of the release agent in the toner is preferably 1 to 30% by mass, more preferably 5 to 20% by mass.

[External additive]
From the viewpoint of improving the charging performance, fluidity, and cleaning properties of the toner, particles such as known inorganic fine particles and organic fine particles and a lubricant can be added as external additives to the surface of the toner particles (toner base particles).
Preferred inorganic fine particles include inorganic fine particles made of silica, titania, alumina, strontium titanate, or the like.
If necessary, these inorganic fine particles may be hydrophobized.
As the organic fine particles, spherical organic fine particles having a number average primary particle diameter of about 10 to 2000 nm can be used. Specifically, homopolymers such as styrene and methyl methacrylate and organic fine particles made of these copolymers can be used.

The lubricant is used for the purpose of further improving the cleaning property and the transfer property. Examples of the lubricant include zinc stearate, salts of aluminum, copper, magnesium, calcium, and zinc oleate. Of higher fatty acids, such as salts of manganese, iron, copper, magnesium, zinc of palmitic acid, salts of copper, magnesium, calcium, zinc of linoleic acid, salts of calcium, zinc of ricinoleic acid, salts of calcium, etc. Metal salts are mentioned. A variety of these external additives may be used in combination.
The amount of the external additive added is preferably 0.1 to 10.0% by mass with respect to 100% by mass of the toner particles.

≪Manufacturing method≫
[Toner manufacturing process]
The method for producing the toner of the present invention is not particularly limited, and examples thereof include known methods such as a kneading and pulverizing method, a suspension polymerization method, an emulsion aggregation method, a dissolution suspension method, a polyester elongation method, and a dispersion polymerization method.

[External addition process]
This step is a step of preparing a toner by adding and mixing external additives as necessary to the surface of the toner base particles. Examples of the method of adding the external additive include a method of adding using various known mixing apparatuses such as a Turbuler mixer, a Henschel mixer, a Nauter mixer, and a V-type mixer. By adding the external additive, the fluidity and chargeability of the toner are improved, and the cleaning property is improved.

≪Developer≫
For example, when the toner described above is mixed with a so-called carrier and used as a two-component developer, or when a nonmagnetic toner is used singly, any of them can be suitably used.

  Although the carrier which comprises a two-component developer is not specifically limited, The following are mentioned.

As the magnetic material, magnetic particles made of conventionally known materials such as metals such as iron, ferrite and magnetite, and alloys of these metals with metals such as aluminum and lead can be used, and in particular, ferrite particles can be used. preferable.
The resin composition for coating the carrier surface is not particularly limited. For example, olefin resin, cyclohexyl methacrylate-methyl methacrylate copolymer, styrene resin, styrene / acrylic resin, silicone resin, ester resin, or fluororesin is used. . The resin for constituting the resin-dispersed carrier is not particularly limited, and known resins can be used. For example, acrylic resin, styrene / acrylic resin, polyester resin, fluorine resin, phenol resin, etc. are used. be able to.
It is also possible to use a so-called resin-dispersed carrier in which the magnetic particles are dispersed in a resin, and a coating layer can be provided on the resin-dispersed carrier.
The volume average particle diameter of the carrier is preferably 15 to 100 μm, more preferably 20 to 60 μm.

  The embodiments to which the present invention can be applied are not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit of the present invention.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "mass part" or "mass%" is represented.

[Production of Toner 1]
<Synthesis of crystalline polyester resin A>
The raw material monomer and radical polymerization initiator of the following addition polymerization resin (styrene / acrylic resin: St-Ac, resin other than polyester resin) unit containing both reactive monomers were placed in a dropping funnel.
Styrene 37 parts by mass n-butyl acrylate 14 parts by mass Acrylic acid 5 parts by mass Polymerization initiator (di-t-butyl peroxide) 7 parts by mass

In addition, the raw material monomer of the following polycondensation resin (crystalline polyester resin: CPEs) unit is put into a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and heated to 170 ° C. to dissolve. I let you.
Tetradecanedioic acid (aliphatic dicarboxylic acid) 388 parts by mass 1,4-butanediol (dialcohol) 162 parts by mass

  Next, the raw material monomer of the addition polymerization resin (St-Ac) was dropped over 90 minutes with stirring, and after aging for 60 minutes, the unreacted addition polymerization monomer was removed under reduced pressure (8 kPa). . The amount of the monomer removed at this time was very small with respect to the raw material monomer ratio of the resin.

Thereafter, 0.8 part by mass of Ti (OBu) ₄ was added as an esterification catalyst, the temperature was raised to 235 ° C., and the reaction was performed at normal pressure (101.3 kPa) for 5 hours and further under reduced pressure (8 kPa) for 1 hour. went.
Next, after cooling to 200 degreeC, the crystalline polyester resin A (hybrid crystalline polyester resin) was obtained by making it react under reduced pressure (20 KPa) for 1 hour. Crystalline polyester resin A contains 10% by mass of resin (St-Ac) units other than CPEs (content of resin units other than CPEs shown in Table 3) with respect to the total amount of the resin. The resin was in the form of grafted CPEs. The crystalline polyester resin A had a number average molecular weight (Mn) of 5000 and a melting point (Tc) of 75 ° C.

<Preparation of aqueous dispersion A of crystalline polyester resin fine particles>
The crystalline polyester resin A (30 parts by mass) was transferred in a molten state to the emulsification disperser “Cavitron CD1010” (manufactured by Eurotech Co., Ltd.) at a transfer rate of 100 parts by mass.
Simultaneously with transfer of the crystalline polyester resin A in the molten state, 70 parts by mass of reagent ammonia water was diluted with ion-exchanged water in the aqueous solvent tank with respect to the emulsifying disperser. Dilute aqueous ammonia having a concentration of 0.37% by mass was transferred at a transfer rate of 0.1 liter per minute while being heated to 100 ° C. with a heat exchanger. Then, by operating this emulsification disperser under the conditions of a rotor rotation speed of 60 Hz and a pressure of 5 kg / cm ² , an aqueous system of crystalline polyester resin fine particles having a volume-based median diameter of 200 nm and a solid content of 30 parts by mass. Dispersion A was prepared.

<Preparation of Aqueous Dispersion A of Amorphous Resin Fine Particles (Styrene / Acrylic Resin A)>
(First stage polymerization)
Interface obtained by dissolving 8 parts by mass of an anionic surfactant (sodium dodecyl sulfonate: SDS) in 3000 parts by mass of ion-exchanged water in a 5 L separable flask equipped with a stirrer, temperature sensor, condenser, and nitrogen introducing device. The activator solution (aqueous medium) was charged, and the internal temperature was raised to 80 ° C. while stirring at a stirring speed of 230 rpm under a nitrogen stream. To this surfactant solution, an initiator solution in which 10 parts by mass of a polymerization initiator (potassium persulfate: KPS) was dissolved in 200 parts by mass of ion-exchanged water was added, and the liquid temperature was again adjusted to 80 ° C.
Styrene 532 parts by mass n-butyl acrylate 200 parts by mass A methacrylic acid 68 parts by mass was added dropwise over 1 hour. Polymerization (first stage polymerization) was performed by heating and stirring the system at 80 ° C. for 2 hours to prepare a resin fine particle dispersion x1.

(Second stage polymerization)
A 5 L reaction vessel equipped with a stirrer, temperature sensor, condenser, and nitrogen introducing device was charged with a solution prepared by dissolving 7 parts by mass of sodium polyoxyethylene dodecyl ether sulfate in 3 L of ion-exchanged water, heated to 98 ° C., 260 parts by mass of a resin fine particle dispersion x1;
Styrene 270 parts by weight n-butyl acrylate 93 parts by weight Methacrylic acid 25 parts by weight n-octyl-3-mercaptopropionate 1.5 parts by weight Behenate behenate 190 parts by weight of monomer and release agent at 90 ° C Add the dissolved solution, mix and disperse for 1 hour with a mechanical disperser “CLEARMIX” (M-Technique) having a circulation path, and disperse the dispersion containing emulsified particles (oil droplets). Prepared. Next, an initiator solution in which 6 parts by mass of potassium persulfate is dissolved in 200 parts by mass of ion-exchanged water is added to this dispersion, and polymerization is performed by heating and stirring the system at 84 ° C. for 1 hour. A particle dispersion x2 was prepared.

(3rd stage polymerization)
A solution prepared by dissolving 11 parts by mass of potassium persulfate in 400 parts by mass of ion-exchanged water was added to the resin particle dispersion x2 obtained as described above. Under a temperature condition of 82 ° C.,
Styrene 417 parts by mass n-butyl acrylate 144 parts by mass Methacrylic acid 39 parts by mass n-Octyl-3-mercaptopropionic acid ester A monomer mixture consisting of 8 parts by mass was added dropwise over 1 hour. After completion of the dropwise addition, polymerization was carried out by heating and stirring for 2 hours, followed by cooling to 28 ° C. to prepare an aqueous dispersion A of amorphous resin fine particles (styrene / acrylic resin A) made of vinyl resin.

  Regarding the obtained aqueous dispersion A of the amorphous resin fine particles, the volume-based median diameter of the amorphous resin fine particles was 210 nm, the glass transition point was 51 ° C., and the weight average molecular weight was 31,000.

[Preparation of dispersion of colorant fine particles]
90 parts by mass of sodium n-dodecyl sulfate was dissolved in 1600 parts by mass of ion-exchanged water with stirring. After stirring this solution, 420 parts by mass of carbon black Mulul-L was gradually added as a colorant, An aqueous dispersion of colorant fine particles was prepared by performing a dispersion treatment using “Mix W Motion CLM-0.8” (manufactured by M Technique Co., Ltd.). With respect to the obtained aqueous dispersion of colorant fine particles, the average particle size (volume-based median diameter) of the colorant fine particles was 110 nm.

<Manufacture of toner>
In a reaction vessel equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introducing device, 504 parts by mass (in terms of solid content) of an aqueous dispersion A of amorphous resin fine particles and an aqueous dispersion A of crystalline polyester resin fine particles After adding 56 parts by mass (in terms of solid content) and 2000 parts by mass of ion-exchanged water, an aqueous solution of sodium hydroxide having a concentration of 25% by mass was added to adjust the pH to 10 (the liquid temperature was 25 ° C.).

  Thereafter, 56 parts by mass (in terms of solid content) of an aqueous dispersion of the above colorant fine particles was added, and then an aqueous solution in which 60 parts by mass of magnesium chloride hexahydrate was dissolved in 60 parts by mass of ion-exchanged water was stirred. And added at 30 ° C. over 10 minutes. Thereafter, the temperature was raised after standing for 3 minutes, and the temperature of the system was raised to 80 ° C. over 60 minutes, and the particle growth reaction was continued while maintaining 80 ° C. Sampling is performed periodically, and the volume-based median diameter of the associated particles is measured using a particle size distribution measuring device “Coulter Multisizer 3” (manufactured by Beckman Coulter), and the volume-based median diameter becomes 6.0 μm. At that time, an aqueous solution in which 190 parts by mass of sodium chloride was dissolved in 760 parts by mass of ion-exchanged water was added to stop particle growth. Further, the temperature is raised and the mixture is heated and stirred in a state of 90 ° C. to promote particle fusion, and the average circularity is measured using a measuring device “FPIA-2100” (manufactured by Sysmex) for the average circularity of the toner. When it reached 0.960, it was cooled to 30 ° C. or lower at a cooling rate of 2.5 ° C./min.

The colored particle dispersion thus obtained was used as a basket type centrifuge “MARK III”.
Solid-liquid separation was performed using a “model number 60 × 40” (manufactured by Matsumoto Machine Co., Ltd.) to form a wet cake. This wet cake was repeatedly washed and solid-liquid separated with the basket-type centrifuge until the electric conductivity of the filtrate reached 5 μS / cm. Thereafter, a “flash jet dryer” (manufactured by Seishin Enterprise Co., Ltd.) was used, and the temperature was 40 The toner particles were obtained by spraying an air stream at 20 ° C. and a humidity of 20% RH until the water content became 0.5 mass% and cooling to 24 ° C.
To 100 parts by mass of the toner particles obtained, 0.6 part by mass of hydrophobic silica (number average primary particle size = 12 nm, degree of hydrophobicity = 68), hydrophobic titanium oxide (number average primary particle size = 20 nm, degree of hydrophobicity) = 63) 1.0 part by mass was added and mixed with a “Henschel mixer” (manufactured by Mitsui Miike Chemical Co., Ltd.) at a rotating blade circumferential speed of 35 mm / sec for 20 minutes at 32 ° C. The toner 1 was produced by applying an external additive treatment to remove coarse particles.

(Manufacture of developer 1)
Developer 1 was manufactured by adding and mixing a ferrite carrier having a volume average particle diameter of 60 μm coated with a silicone resin so that the toner concentration becomes 6% by mass.

[Production of Toners 2-9, 11-13]
In the production of the toner 1, the kind of the crystalline polyester resin (CPEs), the kind of the amorphous resin, and the value of the mass ratio of the amorphous resin to the crystalline polyester resin (the amorphous resin / CPEs described in Table 1). The toners 2 to 9 and 11 to 13 were produced in the same manner as in Table 1 except that Further, in the same manner as in the toner 1, developers 2 to 9 and 11 to 13 were produced.
In addition, about the styrene acrylic resin BE in Table 1, the quantity of methacrylic acid monomer (namely, the quantity of the polar monomer in resin) at the time of synthesize | combining each styrene acrylic resin as shown in Table 2, An aqueous dispersion of amorphous resin fine particles was prepared in the same manner as in the manufacture of the toner 1 except that the styrene / acrylic resin A was changed.
The crystalline polyester resins B to G were synthesized in the same manner as in the synthesis of the crystalline polyester resin A in the production of the toner 1 except that the dicarboxylic acids and dialcohols shown in Table 3 were used.

[Production of Toner 10]
In the production of the toner 1, an amorphous polyester resin particle dispersion A is prepared as follows and used in place of the aqueous dispersion A of the amorphous resin fine particles (styrene / acrylic resin A) in the production of the toner 1. Other than that, Toner 10 was produced in the same manner as Toner 1. Further, a developer 10 was produced in the same manner as the toner 1.

<Preparation of Amorphous Polyester Resin A>
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe,
Bisphenol A propylene oxide 2-mole adduct 428 parts by mass Terephthalic acid 100 parts by mass Fumaric acid 71 parts by mass Polycondensation catalyst (titanium tetraisopropoxide) 3 parts by mass are added in 15 portions, and the mixture is placed at 200 ° C under a nitrogen stream The reaction was carried out for 15 hours while distilling off the water produced.

  Subsequently, it was made to react under reduced pressure of 13.3 kPa (100 mmHg), and when the softening point became 104 degreeC, it took out and the amorphous polyester resin A was obtained.

<Preparation of Amorphous Polyester Resin Particle Dispersion A>
400 parts by mass of the amorphous polyester resin A was pulverized with “Landel mill type: RM” (manufactured by Tokuju Kogakusha Co., Ltd.), mixed with 2552 parts by mass of a 0.26 mass% sodium lauryl sulfate solution prepared in advance, and stirred. While using an ultrasonic homogenizer “US-150T” (manufactured by Nippon Seiki Seisakusho Co., Ltd.), V-LEVEL is ultrasonically dispersed at 300 μA for 120 minutes, and amorphous polyester resin particle dispersion in which amorphous polyester resin A is dispersed. Liquid A was prepared.

[Production of Toner 14]
In the production of the toner 1, the crystalline polyester resin A was changed to the following crystalline polyester resin H, and the aqueous dispersion A of the amorphous resin fine particles was changed to the aqueous dispersion H of the following amorphous resin fine particles. Toner 14 was manufactured. Further, a developer 14 was produced in the same manner as toner 1.

<Synthesis of crystalline polyester resin H>
A raw material monomer of the following addition polymerization resin (styrene / acrylic resin: St-Ac) unit and a radical polymerization initiator containing both reactive monomers were placed in a dropping funnel.
Styrene 34 parts by mass n-butyl acrylate 12 parts by mass Acrylic acid 2 parts by mass Polymerization initiator (di-t-butyl peroxide) 7 parts by mass

In addition, the raw material monomer of the following polycondensation resin (crystalline polyester resin: CPEs) unit is put into a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and heated to 170 ° C. to dissolve. I let you.
Sebacic acid 281 parts by mass 1,12-dodecanediol 283 parts by mass

  Next, the raw material monomer of the addition polymerization resin (St-Ac) was added dropwise over 90 minutes with stirring, and after aging for 60 minutes, the unreacted addition polymerization monomer was removed under reduced pressure (8 kPa). . The amount of the monomer removed at this time was very small with respect to the raw material monomer ratio of the resin.

Thereafter, 0.8 part by mass of Ti (OBu) ₄ was added as an esterification catalyst, the temperature was raised to 235 ° C., and the reaction was performed at normal pressure (101.3 kPa) for 5 hours and further under reduced pressure (8 kPa) for 1 hour. went.
Next, after cooling to 200 degreeC, the crystalline polyester resin H was obtained by making it react under reduced pressure (20 kPa) for 1 hour. The crystalline polyester resin H was a resin in which 10% by mass of a resin (St-Ac) unit other than CPEs was included relative to the total amount, and CPEs were grafted to St-Ac. Moreover, the number average molecular weight (Mn) of crystalline polyester resin H was 9000, and melting | fusing point (Tc) was 76 degreeC.

<Preparation of aqueous dispersion F of amorphous resin fine particles>
(First stage polymerization)
Into a 5 L reaction vessel equipped with a stirrer, temperature sensor, cooling pipe, and nitrogen introduction device, 8 parts by weight of sodium dodecyl sulfate and 3000 parts by weight of ion-exchanged water were charged, and the inside was stirred while stirring at a stirring speed of 230 rpm under a nitrogen stream. The temperature was raised to 80 ° C. After raising the temperature, 10 parts by mass of potassium persulfate dissolved in 200 parts by mass of ion-exchanged water was added, and the liquid temperature was again set to 80 ° C.
Styrene 480 parts by mass n-butyl acrylate 250 parts by mass A monomer mixture composed of 68 parts by mass methacrylic acid was added dropwise over 1 hour, followed by polymerization by heating and stirring at 80 ° C. for 2 hours. Dispersion f1 was prepared.

(Second stage polymerization)
A 5 L reaction vessel equipped with a stirrer, a temperature sensor, a cooling tube, and a nitrogen introducing device was charged with a solution prepared by dissolving 7 parts by mass of polyoxyethylene (2) sodium dodecyl ether sulfate in 3000 parts by mass of ion-exchanged water, and 98 After heating to ° C., 260 parts by mass of the resin fine particle dispersion f1;
Styrene (St) 284 parts by weight n-butyl acrylate (BA) 92 parts by weight Methacrylic acid (MAA) 13 parts by weight n-octyl-3-mercaptopropionate 1.5 parts by weight Release agent: behenate behenate (melting point 73) ° C) A solution of 190 parts by weight of a monomer and a release agent dissolved at 90 ° C was added and mixed for 1 hour with a mechanical disperser “CLEARMIX” (M Technique) having a circulation path. Dispersed to prepare a dispersion containing emulsified particles (oil droplets).
Next, an initiator solution prepared by dissolving 6 parts by mass of potassium persulfate in 200 parts by mass of ion-exchanged water is added to the dispersion, and polymerization is performed by heating and stirring the system at 84 ° C. for 1 hour. A dispersion f2 of resin fine particles was prepared.

(3rd stage polymerization)
Furthermore, after adding 400 parts by mass of ion-exchanged water to the resin fine particle dispersion f2 and mixing well, a solution in which 11 parts by mass of potassium persulfate was dissolved in 400 parts by mass of ion-exchanged water was added, and the temperature was 82 ° C Under the conditions,
Styrene (St) 350 parts by mass n-butyl acrylate (BA) 215 parts by mass Acrylic acid (AA) 30 parts by mass n-octyl-3-mercaptopropionate A monomer mixture consisting of 8 parts by mass over 1 hour It was dripped. After completion of the dropwise addition, polymerization was carried out by heating and stirring for 2 hours, followed by cooling to 28 ° C. to prepare an aqueous dispersion F of amorphous resin fine particles made of vinyl resin (styrene / acrylic resin F).

Regarding the obtained aqueous dispersion F of amorphous resin fine particles, the volume-based median diameter of the amorphous resin fine particles was 220 nm, the glass transition temperature (Tg) was 55 ° C., and the weight average molecular weight (Mw) was 32000. .

[Production of Toner 15]
In the production of the toner 14, the toner 15 was obtained in the same manner except that the aqueous dispersion of fine particles of the crystalline polyester resin H was not added.

[Acid value]
The acid values of the amorphous resin and the crystalline polyester resin used in the toners 1 to 15 were measured as follows. The results are as shown in Table 1.

(Method for measuring acid value (AV))
The acid value is the mass of potassium hydroxide (KOH) required to neutralize the acid contained in 1 g of the amorphous resin or crystalline polyester resin to be measured, expressed in mg. The acid values of the amorphous resin and the crystalline polyester resin were measured according to JIS K0070-1966. Specifically, it measured according to the following procedures.

(1. Preparation of reagents)
Dissolve 1.0 g of phenolphthalein in 90 mL of ethyl alcohol (95% by volume), add ion-exchanged water to make 100 mL, and prepare a “phenolphthalein solution”. 7 g of JIS special grade potassium hydroxide is dissolved in 5 mL of ion exchange water, and ethyl alcohol (95% by volume) is added to make 1 liter. In order to avoid contact with carbon dioxide gas, it is placed in an alkali-resistant container and allowed to stand for 3 days, followed by filtration to produce a “potassium hydroxide solution”. The orientation is in accordance with the description of JIS K0070-1966.

(2. Operation)
(2.a) Main test 2.0 g of a crushed amorphous resin or crystalline polyester resin sample is precisely weighed in a 200 mL Erlenmeyer flask, and 100 mL of a mixed solution of toluene / ethanol (2: 1) is added for 5 hours. Dissolves over time. Subsequently, several drops of the phenolphthalein solution is added as an indicator, and titration is performed using the potassium hydroxide solution. Note that the end point of the titration is when the light red color of the indicator lasts for about 30 seconds.

(2.b) Blank test The same operation as described above is performed except that no sample is used (that is, only a mixed solution of toluene / ethanol (2: 1) is used).

(3) Calculation of acid value The obtained result is substituted into the following formula (A) to calculate the acid value.
Formula (A): A = [(BC) × f × 5.6] / S

here,
A: Acid value (mgKOH / g),
B: Amount of added potassium hydroxide solution for blank test (mL),
C: Amount of addition (mL) of potassium hydroxide solution in this test,
f: Factor of 0.1 mol / liter potassium hydroxide ethanol solution,
S: Sample (g).

[Evaluation]
The following evaluation was performed on the toners 1 to 15 manufactured as described above. The results are as shown in Table 4.
In the following evaluations, ◎ and ○ are acceptable and Δ and × are unacceptable.

<Low temperature fixability>
In a commercially available full-color copier “bizhub PRO C6501” (manufactured by Konica Minolta Co., Ltd.), the fixing device is modified so that the surface temperature of the fixing heat roller can be changed in the range of 100 to 210 ° C. A fixing experiment is performed in which the developer having the toner to be evaluated is loaded and a solid image having a toner adhesion amount of 11 mg / 10 cm ² is fixed on A4 size plain paper (basis weight 80 g / m ² ). It was repeated while changing the temperature to increase in increments of 5 ° C., such as 100 ° C., 105 ° C.,. Next, the printed matter obtained in the fixing experiment at each fixing temperature is folded by a folding machine so that a load is applied to the solid image, and compressed air of 0.35 MPa is blown onto the printed image. The fixing temperature in the fixing experiment with the lowest fixing temperature among the fixing experiments ranked in rank 3 and evaluated as the lower limit fixing temperature. It shows that it is excellent in low temperature fixability, so that this minimum temperature is low.

(Evaluation criteria: Fold fixability)
Rank 5: No crease Rank 4: Peeling according to some folds Rank 3: Peeling fine lines according to folds Rank 2: Peeling thick lines according to folds Rank 1: Large With peeling

(Evaluation criteria: fixing temperature)
A: Fixing temperature 100 ° C. or higher and lower than 110 ° C. O: Fixing temperature 110 ° C. or higher and lower than 120 ° C. Δ: Fixing temperature 120 ° C. or higher and lower than 130 ° C. ×: Fixing temperature 130 ° C. or higher.

<Heat resistant storage>
Take 2 g of toner in a 10 mL glass bottle with an inner diameter of 21 mm, close the lid, shake with Tap Denser KYT-2000 (manufactured by Seishin Enterprise) 600 times at room temperature, and then remove the lid and remove the lid at 50 ° C and 80% RH environment. Left under for 24 hours. Next, place the toner on a 48-mesh (mesh 350 μm) sieve, taking care not to crush the toner aggregates, set the powder tester (manufactured by Hosokawa Micron), and fix it with a press bar and knob nut. After adjusting the vibration strength to a feed width of 1 mm and applying vibration for 10 seconds, the ratio (mass%) of the amount of toner remaining on the sieve was measured.

(Evaluation criteria)
The toner aggregation rate is a value calculated by the following formula.
Toner aggregation rate (%) = residual toner mass on sieve (g) /0.5 (g) × 100
The heat-resistant storage stability of the toner was evaluated according to the criteria described below and used as an index for storage stability.

A: Toner aggregation rate less than 10% by mass O: Toner aggregation rate from 10% to less than 15% by mass Δ: Toner aggregation rate from 15% to less than 20% by mass X: Toner aggregation rate of 20% by mass or more

<Halftone reproducibility>
Charging uniformity was evaluated by halftone reproducibility. A halftone chart was copied with the above evaluator, and the image density of this image was measured at five points in the axial direction of the photoreceptor and evaluated. However, the image density was measured using an image densitometer (Macbeth RD914).

(Evaluation criteria)
A: Density variation is less than 10% O: Density variation is 10% or more and less than 15% Δ: Density variation is 15% or more and less than 20% X: Density variation is 20% or more

<HH transferability>
After the completion of 100,000 printing in a high temperature and high humidity environment (30 ° C., 85% RH atmosphere), an image with an image density of 1.30 (20 mm × 50 mm) was formed, and the transfer rate was calculated from the following formula and evaluated.
Transfer rate = (mass of toner transferred onto transfer material / mass of toner developed on photoreceptor) × 100

(Evaluation criteria)
◎: Transfer rate is 95% or more ◯: Transfer rate is 90% or more and less than 95% △: Transfer rate is 85% or more and less than 90% ×: Transfer rate is less than 85%

Claims (8)

An electrostatic latent image developing toner containing toner particles containing at least a binder resin, a colorant, and a release agent,
The binder resin contains at least a styrene-acrylic resin and a crystalline polyester resin;
The crystalline polyester resin is at least a polycondensate of a dicarboxylic acid having an alkyl chain with 9 to 18 carbon atoms and a dialcohol; and
An electrostatic latent image developing toner satisfying the following formulas (1) to (3):
AV (St−Ac) ≧ AV (CPEs) (1)
20 mg KOH / g ≦ AV (St-Ac) ≦ 50 mg KOH / g (2)
3 mgKOH / g ≦ ΔAV (St-Ac-CPEs) ≦ 30 mgKOH / g (3)
[In the above formulas (1) to (3), AV (St-Ac) represents the acid value of the styrene-acrylic resin. AV (CPEs) represents the acid value of the crystalline polyester resin. ΔAV (St-Ac-CPEs) represents the difference between the acid value of the styrene-acrylic resin and the crystalline polyester resin. ]   The electrostatic latent image developing toner according to claim 1, wherein the crystalline polyester resin is a hybrid resin bonded to a resin other than the polyester resin.   The electrostatic latent image developing toner according to claim 2, wherein the crystalline polyester resin contains a vinyl resin as a resin other than the polyester resin.   4. The electrostatic latent image developing toner according to claim 1, wherein an acid value of the crystalline polyester resin is in a range of 10 to 40 mg KOH / g. 5.   The static difference according to any one of claims 1 to 4, wherein a difference in acid value between the styrene-acrylic resin and the crystalline polyester resin is in a range of 3 to 15 mgKOH / g. Toner for developing electrostatic latent image.   6. The electrostatic latent image according to claim 1, wherein an amount of a polar monomer of the styrene-acrylic resin is in a range of 1.0 to 10.0 mass%. Development toner.   7. The electrostatic latent image developing toner according to claim 1, wherein the crystalline polyester resin comprises an aliphatic dicarboxylic acid and an aliphatic dialcohol.   The electrostatic latent image developing toner according to any one of claims 1 to 7, wherein the alkyl chain of the dialcohol has a carbon number in the range of 4 to 14.