JP6194222B2 - Method for producing toner for developing electrostatic image - Google Patents

Description

  The present invention relates to a method for producing an electrostatic image developing toner, and an electrostatic image developing toner obtained by the method.

In the field of electrophotography, with the development of an electrophotographic system, development of toner for electrophotography corresponding to higher image quality and higher speed is required.
Corresponding to high image quality, a method of obtaining a toner having a narrow particle size distribution and a small particle size is obtained by aggregating and fusing fine resin particles in an aqueous medium to obtain a toner. A toner is manufactured by an aggregation method or an aggregation fusion method. As the binder resin, a polyester resin excellent in low-temperature fixability is used, and in order to satisfy a plurality of performances at the same time, it is also considered to use a mixture of a plurality of resins.

For example, Patent Document 1 discloses an alcohol component containing an aliphatic diol having 2 to 10 carbon atoms and an aliphatic dicarboxylic acid having 8 to 12 carbon atoms for the purpose of improving the environmental stability of charge degree and weighted storage stability. After subjecting the carboxylic acid component containing the compound to a polycondensation reaction, cooling to 40 ° C. or lower, heat treatment at a specific temperature to obtain a crystalline polyester, obtaining an aqueous dispersion containing the crystalline polyester, An aqueous dispersion containing crystalline polyester is mixed with an aqueous dispersion containing an amorphous resin, and then subjected to an agglomeration step to obtain an aqueous dispersion of aggregated particles. A method for producing a binder resin for toner having a step of obtaining an aqueous dispersion is disclosed.
In Patent Document 2, a non-crystalline polyester having a hydroxyl group and a polyisocyanate are added for the purpose of improving low-temperature fixability, heat-resistant storage stability, and hot offset resistance, and a prepolymer is synthesized. A first liquid is prepared by dissolving or dispersing a composition containing a functional polyester, a prepolymer, a compound having an amino group, a release agent and a colorant in an organic solvent. A liquid containing the first particles is prepared by emulsifying or dispersing in an aqueous medium containing the second liquid to prepare a liquid containing the first particles by removing the organic solvent from the second liquid. And a liquid containing second particles is prepared, wherein the amorphous polyester having a hydroxyl group, the prepolymer, the first particles, and the second particles satisfy a specific condition. , Crystalline polyester, non Sexual polyester, urea-modified polyester, the production method of the toner containing a releasing agent and a colorant are disclosed.

In Patent Document 3, resin particles (A) containing a resin containing 90% by weight or more of a polyester resin (a) for the purpose of improving low-temperature fixability and heat-resistant storage stability, a wax and a softening point of 75 to 105 ° C Release agent particles containing a certain polyester resin (b) in a weight ratio of 95/5 to 55/45, and an aggregating agent are mixed in an aqueous medium to obtain aggregated particles (1). And the resin particles (B) containing the polyester resin (c) serving as the shell are mixed to obtain aggregated particles (2), and the particles constituting the aggregated particles (2) are fused to obtain core-shell particles. A method for producing a toner for developing an electrostatic latent image including a process is disclosed.
In Patent Document 4, the binder resin contains a crystalline polyester resin and a styrene-acrylic resin for the purpose of improving low-temperature fixing characteristics, heat-resistant storage stability, fixing separation performance, and suppressing document offset. The resin contains 5% by mass or more and 30% by mass or less of the crystalline polyester resin, and the styrene-acrylic resin has 1 mass of the structural unit derived from methyl methacrylate as a constituent component with respect to the total of the binder resin and wax A core layer comprising a binder resin and a wax, and a shell layer formed by coating the core particle, wherein the resin constituting the shell layer contains a styrene-acryl-modified polyester resin. A toner for developing an electrostatic charge image having a core / shell structure having the following structure is disclosed.

JP 2011-107341 A JP 2012-189967 A JP 2012-128024 A JP 2012-255957 A

As the speed of electrophotographic printing increases, it is necessary to fix with less energy at the time of printing. For this reason, the toner to be used is required to have fixability at a low temperature. Attempts have been made to use a crystalline resin having a low melting point in order to improve low-temperature fixability. However, there is a problem in that the storage stability of the toner at a high temperature, that is, the so-called heat-resistant storage stability is lowered. In particular, when the crystalline resin and the amorphous resin are compatible, the heat resistant storage stability is further deteriorated.
In order to maintain the crystallinity of the crystalline resin, it is necessary not to be compatible with the amorphous resin used at the same time. However, when the crystalline resin is unevenly distributed in the toner, there is a problem that the chargeability is deteriorated because the toner surface is likely to be exposed.
An object of the present invention is to provide a method for producing an electrostatic image developing toner capable of obtaining an electrostatic image developing toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability, and an electrostatic image obtained by the production method. An object is to provide a toner for developing a charge image.

  The inventor considered that the factors affecting the low-temperature fixability, the heat-resistant storage stability, and the chargeability are the dispersion state of the resin in the toner. As a result, electrostatic charge image development with excellent low-temperature fixability, heat-resistant storage stability and chargeability is achieved by aggregating and fusing resin particles containing specific crystalline polyester and resin particles containing amorphous polyester. It has been found that a toner can be obtained.

That is, the present invention provides the following [1] and [2].
[1] Contains a crystalline polyester (A) in which the proportion of carboxy groups derived from a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less among carboxy groups at the end of the polyester chain is 70 mol% or more A step I of obtaining an agglomerate X in a water-based medium, and a step II of fusing the agglomerate X, and a resin particle containing an amorphous polyester (B) A method for producing a toner for developing a charge image.
[2] A toner for developing an electrostatic image obtained by the above production method.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the electrostatic charge image developing toner which can obtain the electrostatic charge image developing toner which is compatible in low-temperature fixability and heat-resistant storage property, and is excellent in charging property, and the electrostatic charge obtained by the method An image developing toner can be provided.

[Method for producing toner for developing electrostatic image]
In the method for producing a toner for developing an electrostatic charge image according to the present invention, the proportion of carboxy groups derived from dicarboxylic acid monomers having a second dissociation constant (pKa2) of 5 or less among carboxy groups at the end of the polyester chain is 70 mol%. Step I for obtaining in the aqueous medium an aggregate X comprising the resin particles containing the crystalline polyester (A) and the resin particles containing the amorphous polyester (B), and the aggregate X Step II for fusing.
Hereinafter, the “electrostatic image developing toner” may be simply referred to as “toner”.

The reason why the toner for developing an electrostatic image obtained by the production method of the present invention is excellent in low-temperature fixability, heat-resistant storage stability and chargeability is not clear, but is considered as follows.
In the production method of the present invention, resin particles containing crystalline polyester and resin particles containing amorphous polyester are aggregated and fused in an aqueous medium to obtain a toner.
The crystalline polyester (A) used in the present invention is a crystalline polyester in which the proportion of carboxy groups derived from a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less is 70 mol% or more. In addition, the amorphous polyester (B) is composed of a monomer having a double bond and the like, and the second dissociation constant of the carboxy group at the end of the polyester chain is considered to be low. It is considered that the crystalline polyester (A) used in the present invention is close to agglomeration and aggregates uniformly. For this reason, the uneven distribution of the crystalline polyester (A) does not occur, and the exposure to the toner surface during the heating of the fusion does not easily occur. Therefore, it is considered that the heat resistant storage stability and the charging property are good. Further, since the resin particles containing the crystalline polyester (A) maintain crystallinity by themselves, it is considered that a certain crystal size can be maintained and low-temperature fixability is excellent.

<Process I>
In Step I, a crystalline polyester (A) in which the proportion of carboxy groups derived from a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less among carboxy groups at the end of the polyester chain is 70 mol% or more is used. This is a step of obtaining an agglomerate X containing resin particles contained therein and resin particles containing amorphous polyester (B) in an aqueous medium.

  Step I is a step Ia in which the resin particles containing the crystalline polyester (A) and the resin particles containing the amorphous polyester (B) are aggregated in the aqueous medium to obtain the core aggregate x. And resin particles containing the amorphous polyester for shell (C) are further mixed in the aqueous medium to aggregate the resin particles containing the core aggregate x and the amorphous polyester (C). And step Ib for obtaining the aggregate X (first aspect of step I). By using the aggregate X obtained in this manner, the step II described later is carried out, whereby the part derived from the core aggregate is derived from the core and the resin particles containing the shell amorphous polyester (C). Thus, a toner having a core-shell structure in which the portion to be used is a shell can be obtained.

Further, the step Ib may be omitted. That is, step I includes a step of aggregating resin particles containing crystalline polyester (A) and resin particles containing amorphous polyester (B) in the aqueous medium to obtain aggregate X. (Second aspect of step I). A toner having a single structure, that is, a non-core-shell structure can be obtained by performing Step II described later using the aggregate X thus obtained.
Hereinafter, although the 1st aspect of the process I is demonstrated, the 2nd aspect of the process I omits the process Ib in the 1st aspect of the process I.

(Resin particles containing crystalline polyester (A))
The resin particle containing crystalline polyester (A) contains crystalline polyester (A).

  The resin particles containing the crystalline polyester (A) may contain components other than the crystalline polyester (A) as long as the effects of the present invention are not impaired, but both low-temperature fixability and heat-resistant storage stability are compatible. From the viewpoint of obtaining a toner for developing an electrostatic image having excellent chargeability, it is preferable not to contain any components other than the crystalline polyester (A). The content of the crystalline polyester (A) in the resin particles containing the crystalline polyester (A) is preferably 80% by mass or more, more preferably 90 to 100% by mass, still more preferably 95 to 100% by mass, and more. More preferably, it is 99-100 mass%, More preferably, it is substantially 100 mass%.

In the present invention, the crystallinity of the resin such as crystalline polyester (A) is the ratio between the softening point and the maximum peak temperature of the endotherm measured by the differential scanning calorimeter (DSC), that is, “softening point / maximum peak temperature of endotherm”. It is represented by the crystallinity index defined by Generally, when the crystallinity index exceeds 1.4, the resin is amorphous, and when it is less than 0.6, the crystallinity is low and there are many amorphous portions. In the present invention, the “crystalline” resin refers to a resin having a crystallinity index of 0.6 to 1.4, preferably 0.8 to 1.2, and more preferably 0.9 to 1.1. The “amorphous” resin means a resin having a crystallinity index exceeding 1.4 or less than 0.6.
The above “maximum endothermic peak temperature” refers to the temperature of the peak on the highest temperature side among the endothermic peaks observed under the measurement method conditions described in the examples. If the maximum peak temperature is within 20 ° C. from the softening point, the maximum peak temperature is the melting point of the crystalline resin (crystalline resin), and the peak at which the difference from the softening point exceeds 20 ° C. is glass of amorphous resin. The peak is attributed to the transition.
The crystallinity of the resin can be adjusted by the types and ratios of the raw material monomers, production conditions (for example, reaction temperature, reaction time, cooling rate) and the like.

The volume median particle size of the resin particles containing the crystalline polyester (A) is preferably 50 nm or more from the viewpoint of easy aggregation, a toner having excellent low-temperature fixability, heat-resistant storage stability and chargeability. More preferably, it is 100 nm or more, More preferably, it is 120 nm or more, More preferably, it is 150 nm or more, Preferably it is 300 nm or less, More preferably, it is 250 nm or less, More preferably, it is 200 nm or less, More preferably, it is 195 nm or less.
The resin particles containing the crystalline polyester (A) can be suitably produced by adding an aqueous medium to the crystalline polyester (A) and carrying out phase inversion emulsification.

≪Crystalline polyester (A) ≫
The crystalline polyester (A) is a resin in which the proportion of carboxy groups derived from a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less among carboxy groups at the end of the polyester chain is 70 mol% or more. .
The softening point of the crystalline polyester (A) used in the present invention is preferably 60 ° C. or higher, more preferably 70 ° C. or higher, and still more preferably, from the viewpoint of obtaining a toner having excellent low-temperature fixability, heat resistant storage stability and chargeability. 75 ° C. or higher, more preferably 79 ° C. or higher, still more preferably 80 ° C. or higher, preferably 100 ° C. or lower, more preferably 95 ° C. or lower, still more preferably 90 ° C. or lower, still more preferably 85 ° C. Below, it is 82 degrees C or less still more preferably.
The melting point of the crystalline polyester (A) used in the present invention is preferably 55 ° C. or higher, more preferably 60 ° C. or higher, still more preferably 70 ° C. or higher, and still more preferably 75 ° C. or higher, from the same viewpoint. Still more preferably, it is 76 degreeC or more, Preferably it is 95 degreeC or less, More preferably, it is 90 degreeC or less, More preferably, it is 85 degreeC or less, More preferably, it is 80 degreeC or less.

From the same viewpoint, the acid value of the crystalline polyester (A) is preferably 1 mgKOH / g or more, more preferably 5 mgKOH / g or more, still more preferably 10 mgKOH / g or more, still more preferably 15 mgKOH / g or more, Moreover, it is preferably 40 mgKOH / g or less, more preferably 35 mgKOH / g or less, still more preferably 30 mgKOH / g or less, and still more preferably 25 mgKOH / g or less.
The softening point, melting point, and acid value can be easily adjusted by adjusting the raw material monomer composition, molecular weight, catalyst amount, etc., or selecting reaction conditions.

  The crystalline polyester (A) may be a crystalline polyester composed only of a crystalline polyester portion obtained by polymerizing a carboxylic acid and an alcohol, and an amorphous portion or the like to the extent that the effect of the present invention is not impaired. You may have other parts. In the crystalline polyester (A), the content of the crystalline polyester portion obtained by polymerizing carboxylic acid and alcohol is preferably 80 mol% or more, more preferably 90 mol% or more, and still more preferably 95 mol% or more. More preferably, it is 99 mol% or more.

[Percentage of carboxy groups derived from dicarboxylic acid monomers having a pKa2 of 5 or less of the carboxy groups at the ends of the polyester chain of the resin]
The ratio of the carboxy group resulting from the dicarboxylic acid monomer whose 2nd dissociation constant (pKa2) is 5 or less among the carboxy groups of the polyester chain terminal of crystalline polyester (A) is 70 mol% or more.
When the proportion is less than 70 mol%, a toner having excellent low-temperature fixability, heat-resistant storage stability and chargeability cannot be obtained. From this viewpoint, the proportion is preferably 72 mol% or more, more preferably 75 mol% or more, still more preferably 78 mol% or more, and preferably 100 mol% or less, preferably 95 mol% or less, more Preferably it is 92 mol% or less, More preferably, it is 90 mol% or less. In addition, the said ratio can be measured by the method as described in an Example.

The dicarboxylic acid monomer having the second dissociation constant (pKa2) of 5 or less is not particularly limited, but is preferably a dicarboxylic acid compound having an unsaturated bond adjacent to the carboxy group. Since the dicarboxylic acid compound has an unsaturated bond, it uniformly aggregates with the amorphous polyester in an aqueous medium, and has the effect of improving the chargeability, low-temperature fixability, and heat-resistant storage stability of the resulting toner.
Specifically, the dicarboxylic acid monomer having the second dissociation constant (pKa2) of 5 or less is preferably fumaric acid (pKa2: 4.4), terephthalic acid (pKa2: 4.8), isophthalic acid (pKa2: 4.5) and oxalic acid (pKa2: 4.2), more preferably one or more selected from fumaric acid, terephthalic acid and isophthalic acid, still more preferably fumaric acid and isophthalic acid. One or more selected from acids.

The carboxylic acid that forms the carboxy group at the end of the polyester chain of the crystalline polyester (A) may contain a carboxylic acid monomer having a second dissociation constant (pKa2) greater than 5.
Examples of the carboxylic acid monomer having a second dissociation constant (pKa2) larger than 5 include aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and trivalent or higher polyvalent carboxylic acids, and aliphatic dicarboxylic acids are preferred. Further, acid anhydrides of these carboxylic acids and alkyl (1 to 3 carbon atoms) esters thereof may be used. These carboxylic acid components can be used alone or in combination of two or more.

Aliphatic dicarboxylic acids having a second dissociation constant (pKa2) greater than 5 are preferably adipic acid (pKa2: 5.4), azelaic acid (pKa2: 5.4), dodecanedioic acid (pKa2: 5.4) Succinic acid (pKa2: 5.6), sebacic acid (1,8-octanedicarboxylic acid) (pKa2: 5.5), suberic acid (pKa2: 5.5) itaconic acid (pKa2: 5.5) malonic acid (PKa2: 5.7) one or more selected from maleic acid (pKa2: 6.1), citraconic acid (pKa2: 6.2) dodecenyl succinic acid (pKa2: 6.7), more preferably succinic acid and One or more selected from sebacic acid (1,8-octanedicarboxylic acid).
The aromatic dicarboxylic acid having a second dissociation constant (pKa2) greater than 5 is preferably phthalic acid (pKa2: 5.3).
The carboxylic acid forming the carboxy group at the end of the polyester chain of the crystalline polyester (A) may contain a trivalent or higher polyvalent carboxylic acid.
The trivalent or higher polyvalent carboxylic acid is preferably at least one selected from trimellitic acid and hemimellitic acid.

[Carboxylic acid forming carboxy group inside polyester chain]
It is preferable that 70 mol% or more of the carboxylic acid forming the carboxy group inside the polyester chain of the crystalline polyester (A) is a saturated aliphatic dicarboxylic acid. Thereby, a toner having excellent low-temperature fixability, heat-resistant storage stability and chargeability can be obtained. From this viewpoint, the content of the saturated aliphatic dicarboxylic acid in the carboxylic acid forming the carboxy group inside the polyester chain of the crystalline polyester (A) is more preferably 72 mol% or more, and further preferably 75 mol% or more. More preferably, it is 78 mol% or more, More preferably, it is 98 mol% or less, More preferably, it is 90 mol% or less, More preferably, it is 85 mol% or less. In addition, the said numerical value can be measured by the method as described in an Example.

  Specific examples of the saturated aliphatic dicarboxylic acid include one or more selected from oxalic acid, malonic acid, succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, and dodecanedioic acid. Among these, succinic acid, adipic acid, sebacic acid, and dodecanedioic acid are preferable from the viewpoint of obtaining a toner having excellent low-temperature fixability, heat-resistant storage stability, and chargeability, and one selected from succinic acid, adipic acid, and sebacic acid The above is more preferable, one or more selected from succinic acid and sebacic acid is still more preferable, and sebacic acid is still more preferable.

The carboxylic acid forming the carboxy group inside the polyester chain of the crystalline polyester (A) may contain a carboxylic acid other than the saturated aliphatic dicarboxylic acid.
Examples of the carboxylic acid include dicarboxylic acid monomers having the second dissociation constant (pKa2) of 5 or less.

〔carboxylic acid〕
Second dissociation constant (pKa2) in the total amount of carboxylic acid of the crystalline polyester (A), that is, in the total amount of carboxylic acid forming a carboxy group at the end of the polyester chain and carboxylic acid forming a carboxy group inside the polyester chain. The content of the dicarboxylic acid monomer of 5 or less is preferably 1 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% from the viewpoint of obtaining a toner having excellent low-temperature fixability, heat-resistant storage stability and chargeability. More preferably, it is at least 10 mol%, preferably at most 70 mol%, more preferably at most 40 mol%, still more preferably at most 30 mol%, still more preferably at most 20 mol%.
The content of the saturated aliphatic dicarboxylic acid in the total amount of the carboxylic acid of the crystalline polyester (A) is preferably 30 mol% or more from the viewpoint of obtaining a toner having excellent low-temperature fixability, heat-resistant storage stability and chargeability. More preferably, it is 60 mol% or more, more preferably 70 mol% or more, still more preferably 80 mol% or more, preferably 98 mol% or less, more preferably 95 mol% or less, still more preferably 90 mol%. % Or less, more preferably 88 mol% or less.

〔alcohol〕
The alcohol that forms the polyester chain of the crystalline polyester (A) is not particularly limited, and examples thereof include aliphatic diols, aromatic diols, and trivalent or higher polyhydric alcohols. These alcohol components can be used alone or in combination of two or more.
The alcohol is preferably an aliphatic diol from the viewpoint of increasing the crystallinity of the polyester. Examples of the aliphatic diol include 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,11-undecanediol and the like from the same viewpoint. 1,9-nonanediol, 1,10-decanediol, and 1,12-dodecanediol are preferred, 1,10-decanediol and 1,12-dodecanediol are more preferred, and 1,10 is more preferred. -Decanediol.
From the same viewpoint, the content of the aliphatic diol is preferably 60 mol% or more, more preferably 80 to 100 mol%, still more preferably 90 to 100 mol%, and still more preferably 95 to 100 mol in the alcohol component. %, More preferably 100 mol%.

  The ratio of the carboxylic acid component to 100 mol parts of the alcohol component that is the raw material monomer of the crystalline polyester (A) is preferably 90 mol parts or more, more preferably 95 mol parts or more, and still more preferably, from the viewpoint of reactivity and physical property adjustment. Is 98 mol parts or more, more preferably 100 mol parts or more, and preferably 150 mol parts or less, more preferably 120 mol parts or less, still more preferably 110 mol parts or less.

≪Method for producing crystalline polyester (A) ≫
The crystalline polyester (A) is preferably obtained through a production method including a step of reacting a precursor crystalline polyester with a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less. Thereby, the dicarboxylic acid monomer whose 2nd dissociation constant (pKa2) is 5 or less can be selectively formed in the polyester chain terminal.
From the same viewpoint, the precursor crystalline polyester preferably has a reaction rate of 95% or more in the condensation polymerization of the carboxylic acid component and the alcohol component.

In the production of the crystalline polyester (A), first, raw materials of the precursor crystalline polyester are blended, and preferably a polycondensation reaction (first polycondensation reaction) is performed until the reaction rate of both raw materials becomes 95% or more. A precursor crystalline polyester is obtained. Next, the crystalline polyester (A) is prepared by blending the precursor crystalline polyester with a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less and performing a condensation polymerization reaction (second condensation polymerization reaction). Can be obtained.
Here, the carboxylic acid compounded in the first condensation polymerization reaction may contain a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less. Moreover, the carboxylic acid blended in the second polycondensation reaction may contain a carboxylic acid monomer larger than the second dissociation constant (pKa2) 5. However, in the first polycondensation reaction, it is preferable to blend raw materials other than the dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less among the raw materials of the crystalline polyester constituting the crystalline polyester (A). In the second polycondensation reaction, it is preferable to mix a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less among the raw materials of the crystalline polyester constituting the crystalline polyester (A).

In the first polycondensation reaction, an esterification catalyst may be blended, and an esterification cocatalyst may be blended. Moreover, you may mix | blend a polymerization inhibitor at the time of a 2nd condensation polymerization reaction.
The reaction temperature of the first polycondensation reaction is preferably 150 ° C. or higher, more preferably 180 ° C. or higher, still more preferably 200 ° C. or higher, preferably 250 ° C. or lower, more preferably 240 ° C. or lower, still more preferably. Is 230 ° C. or lower.
The reaction temperature of the second polycondensation reaction is preferably 180 ° C. or higher, more preferably 190 ° C. or higher, further preferably 200 ° C. or higher, preferably 250 ° C. or lower, more preferably 240 ° C. or lower, still more preferably. Is 230 ° C. or lower.

[Esterification catalyst]
Examples of the esterification catalyst suitably used for the condensation polymerization include a titanium compound and a tin (II) compound having no Sn-C bond, and these may be used alone or in combination of two or more. it can.

As a titanium compound, the titanium compound which has a Ti-O bond is preferable, and the compound which has a C1-C28 alkoxy group, an alkenyloxy group, or an acyloxy group is more preferable.
Examples of the tin (II) compound having no Sn—C bond include a tin (II) compound having a Sn—O bond, a tin (II) compound having a Sn—X (X represents a halogen atom) bond, and the like. Preferred is a tin (II) compound having a Sn-O bond, and among them, di (2-ethylhexanoic acid) tin (II) is more preferable from the viewpoints of reactivity, molecular weight adjustment, and resin physical property adjustment. .

  The amount of the esterification catalyst is preferably from the viewpoint of reactivity, molecular weight adjustment and resin physical property adjustment to 100 parts by mass of the total amount of the alcohol component and carboxylic acid component of the crystalline polyester (A). 1 part by mass or more, more preferably 0.2 part by mass or more, further preferably 0.3 part by mass or more, still more preferably 0.5 part by mass or more, and preferably 3 parts by mass or less, more preferably 2 parts by mass or less, more preferably 1 part by mass or less.

[Esterification promoter]
The esterification cocatalyst need not be used, but may be used. As the esterification cocatalyst, a pyrogallol compound is preferred. This pyrogallol compound has a benzene ring in which three hydrogen atoms adjacent to each other are substituted with a hydroxyl group, and pyrogallol, gallic acid, gallic acid ester, 2,3,4-trihydroxybenzophenone, 2,2 ′ Benzophenone derivatives such as 3,3,4-tetrahydroxybenzophenone, catechin derivatives such as epigallocatechin and epigallocatechin gallate, and the like, and gallic acid is preferred from the viewpoint of reactivity.

(Polymerization inhibitor)
The polymerization inhibitor is not particularly limited, but 4-t-butylcatechol is preferable.

(Resin particles containing amorphous polyester (B))
The resin particles containing the amorphous polyester (B) may contain components other than the amorphous polyester (B) as long as the effects of the present invention are not impaired. From the viewpoint of obtaining a toner for developing an electrostatic charge image that is compatible and excellent in chargeability, it is preferable not to contain any components other than the amorphous polyester (B). The content of the amorphous polyester (B) in the resin particles containing the amorphous polyester (B) is preferably 80% by mass or more, more preferably 90 to 100% by mass, still more preferably 95 to 100% by mass. More preferably, it is 99-100 mass%, More preferably, it is substantially 100 mass%.

The volume median particle size of the resin particles containing the amorphous polyester (B) is preferably 80 nm or more from the viewpoint of easy aggregation, a toner having excellent low-temperature fixability, heat-resistant storage stability and chargeability. More preferably, it is 100 nm or more, More preferably, it is 120 nm or more, More preferably, it is 140 nm or more, Preferably it is 250 nm or less, More preferably, it is 200 nm or less, More preferably, it is 160 nm or less, More preferably, it is 150 nm or less.
The resin particles containing the amorphous polyester (B) can be suitably produced by adding an aqueous medium to the amorphous polyester (B) and performing phase inversion emulsification.

≪Amorphous polyester (B) ≫
The softening point of the amorphous polyester (B) is preferably 70 ° C. or higher, more preferably 75 ° C. or higher, more preferably 80 ° C. or higher, from the viewpoint of obtaining a toner having excellent low-temperature fixability, heat-resistant storage stability and chargeability. Still more preferably 82 ° C or higher, still more preferably 83 ° C or higher, preferably 120 ° C or lower, more preferably 110 ° C or lower, more preferably 105 ° C or lower, still more preferably 100 ° C or lower, still more preferably. Is 95 ° C. or lower, more preferably 90 ° C. or lower.
Further, from the same viewpoint, the glass transition temperature of the amorphous polyester (B) used in the present invention is preferably 25 ° C. or higher, more preferably 30 ° C. or higher, still more preferably 35 ° C. or higher, still more preferably 40. It is preferably at least 70 ° C, more preferably at most 60 ° C, even more preferably at most 55 ° C, and even more preferably at most 50 ° C.

From the same viewpoint, the acid value of the amorphous polyester (B) is preferably 1 mgKOH / g or more, more preferably 5 mgKOH / g or more, still more preferably 10 mgKOH / g or more, still more preferably 15 mgKOH / g or more. Moreover, it is preferably 35 mgKOH / g or less, more preferably 30 mgKOH / g or less, still more preferably 25 mgKOH / g or less, and still more preferably 20 mgKOH / g or less.
The softening point, glass transition temperature, and acid value can be easily adjusted by adjusting the raw material monomer composition, molecular weight, catalyst amount, etc., or by selecting reaction conditions.

  This amorphous polyester (B) may be an amorphous polyester composed only of an amorphous polyester portion obtained by polymerizing a carboxylic acid and an alcohol, and is crystalline to such an extent that the effects of the present invention are not impaired. You may have other parts, such as a part. In the amorphous polyester resin (B), the content of the amorphous polyester portion obtained by polymerizing carboxylic acid and alcohol is preferably 80 mol% or more, more preferably 90 mol% or more, and still more preferably. It is 95 mol% or more, more preferably 99 mol% or more.

〔carboxylic acid〕
Examples of the carboxylic acid component of the amorphous polyester (B) include aliphatic dicarboxylic acid, aromatic dicarboxylic acid, and trivalent or higher polyvalent carboxylic acid. One or both of aliphatic dicarboxylic acid and aromatic dicarboxylic acid It is preferable to include, and it is more preferable to include both. Further, acid anhydrides of these carboxylic acids and alkyl (1 to 3 carbon atoms) esters thereof may be used. These carboxylic acid components can be used alone or in combination of two or more.

Specific examples of the aromatic dicarboxylic acid include terephthalic acid, phthalic acid, and isophthalic acid. Among these, terephthalic acid is preferable from the viewpoint of obtaining a toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability.
The content of the aromatic dicarboxylic acid is preferably 10 mol% or more, more preferably 20 mol% or more in the carboxylic acid component, from the viewpoint of obtaining a toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability. More preferably, it is 25 mol% or more, preferably 45 mol% or less, more preferably 40 mol% or less, still more preferably 35 mol% or less.
The aliphatic dicarboxylic acid preferably contains an aliphatic dicarboxylic acid having 2 to 6 carbon atoms.
Specific examples of the aliphatic dicarboxylic acid include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid ( 1,10-decanedicarboxylic acid). Examples of the aliphatic dicarboxylic acid include succinic acid substituted with an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms such as dodecyl succinic acid, dodecenyl succinic acid, and octenyl succinic acid. . Among these, fumaric acid, dodecenyl succinic acid, and octenyl succinic acid are preferable, and fumaric acid and dodecenyl succinic acid are more preferable from the viewpoint of obtaining a toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability.

  From the same viewpoint, the content of the aliphatic dicarboxylic acid is preferably 40 mol% or more, more preferably 50 mol% or more, still more preferably 60 mol% or more, and still more preferably 65 mol% or more in the carboxylic acid component. Moreover, it is preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, and still more preferably 75 mol% or less.

[Carboxylic acid forming carboxy group at the end of polyester chain]
In the amorphous polyester (B), the ratio of carboxy groups derived from dicarboxylic acid monomers having a second dissociation constant (pKa2) of 5 or less among carboxy groups at the end of the polyester chain is 70 mol% or more. preferable. Thereby, the cohesiveness of amorphous polyester (B) and crystalline polyester (A) becomes close, and it aggregates uniformly. Therefore, uneven distribution of the crystalline polyester does not occur, and exposure to the toner surface during the heating of the fusion hardly occurs, so that it is considered that the heat resistant storage stability and the chargeability are improved.
From this viewpoint, the proportion is preferably 72 mol% or more, more preferably 75 mol% or more, still more preferably 78 mol% or more, and preferably 95 mol% or less, more preferably 92 mol% or less, More preferably, it is 90 mol% or less.

The dicarboxylic acid monomer having the second dissociation constant (pKa2) of 5 or less is not particularly limited, but is preferably a dicarboxylic acid compound having an unsaturated bond adjacent to the carboxy group. Since the dicarboxylic acid compound has an unsaturated bond, it uniformly aggregates with the crystalline polyester of the present invention in an aqueous medium, and has the effect of improving the chargeability, low-temperature fixability, and heat-resistant storage stability of the resulting toner.
Specifically, the dicarboxylic acid monomer having the second dissociation constant (pKa2) of 5 or less is preferably fumaric acid (pKa2: 4.4), terephthalic acid (pKa2: 4.8), isophthalic acid (pKa2: 4.5) and oxalic acid (pKa2: 4.2), more preferably one or more selected from fumaric acid, terephthalic acid and isophthalic acid, still more preferably fumaric acid and One or more selected from terephthalic acid.

The carboxylic acid that forms the carboxy group at the end of the polyester chain of the amorphous polyester (B) may contain a carboxylic acid monomer having a second dissociation constant (pKa2) greater than 5.
Examples of the carboxylic acid monomer having a second dissociation constant (pKa2) larger than 5 include aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and trivalent or higher polyvalent carboxylic acids, and aliphatic dicarboxylic acids are preferred. Further, acid anhydrides of these carboxylic acids and alkyl (1 to 3 carbon atoms) esters thereof may be used. These carboxylic acid components can be used alone or in combination of two or more.

Aliphatic dicarboxylic acids having a second dissociation constant (pKa2) greater than 5 are preferably dodecenyl succinic acid (pKa2: 6.7), succinic acid (pKa2: 5.6), sebacic acid (1,8-octanedicarboxylic acid) ) (PKa2: 5.5), maleic acid (pKa2: 6.1), adipic acid (pKa2: 5.4), azelaic acid (pKa2: 5.4), dodecanedioic acid (pKa2: 5.4), One or more selected from suberic acid (pKa2: 5.5) itaconic acid (pKa2: 5.5) malonic acid (pKa2: 5.7) and citraconic acid (pKa2: 6.2), more preferably dodecenyl succinate One or more selected from acids, succinic acid and sebacic acid (1,8-octanedicarboxylic acid), more preferably dodecenyl succinic acid.
The aromatic dicarboxylic acid having a second dissociation constant (pKa2) greater than 5 is preferably phthalic acid (pKa2: 5.3).
The carboxylic acid that forms the carboxy group at the end of the polyester chain of the amorphous polyester (B) may contain a trivalent or higher polyvalent carboxylic acid.
The trivalent or higher polyvalent carboxylic acid is preferably at least one selected from trimellitic acid and hemimellitic acid.

〔alcohol〕
The alcohol that forms the polyester chain of the amorphous polyester (B) is not particularly limited, and examples thereof include aliphatic diols, aromatic diols, and trihydric or higher polyhydric alcohols. These alcohols can be used alone or in combination of two or more.
This alcohol preferably contains an aromatic diol from the viewpoint of enhancing the amorphous nature of the polyester, more preferably contains an alkylene oxide adduct of bisphenol A represented by the following formula (I). More preferred is an alkylene oxide adduct of bisphenol A represented by the formula (I).

(In the formula, R represents an alkylene group having 2 or 3 carbon atoms. X and y are average added moles of an alkyleneoxy group, represent a positive number, and the sum of x and y is preferably 1 or more. More preferably 1.5 or more, still more preferably 2 or more, and preferably 16 or less, more preferably 5 or less, still more preferably 3 or less.)

As the alkylene oxide adduct of bisphenol A represented by the above formula (I), specifically, a polyoxypropylene adduct of 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4- Hydroxyphenyl) propane polyoxyethylene adduct and the like.
The alkylene oxide adduct of bisphenol A represented by the formula (I) is preferably 70 to 100 mol%, more preferably 80 in the alcohol component from the viewpoints of low-temperature fixability, heat-resistant storage stability and chargeability of the toner. To 100 mol%, more preferably 90 to 100 mol%.

  The ratio of the carboxylic acid component to 100 mol parts of the alcohol component which is a raw material monomer of the amorphous polyester (B) is preferably 90 mol parts or more, more preferably 93 mol parts or more, from the viewpoint of reactivity and physical property adjustment. Preferably it is 95 mol part or more, More preferably, it is 98 mol part or more, Preferably it is 150 mol part or less, More preferably, it is 120 mol part or less, More preferably, it is 110 mol part or less.

≪Method for producing amorphous polyester (B) ≫
The amorphous polyester (B) is preferably obtained through a production method including a step of reacting a precursor amorphous polyester with a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less. Thereby, the dicarboxylic acid monomer whose 2nd dissociation constant (pKa2) is 5 or less can be selectively formed in the polyester chain terminal.
From the same viewpoint, the precursor amorphous polyester preferably has a reaction rate of 95% or more in the condensation polymerization of the carboxylic acid component and the alcohol component.

In the production of the amorphous polyester (B), first, a carboxylic acid and an alcohol, which are raw materials of the precursor amorphous polyester, are blended, and preferably a polycondensation reaction (until the reaction rate of both raw materials reaches 95% or more) A first polycondensation reaction) is performed to obtain a precursor amorphous polyester polyester. Next, the precursor amorphous polyester is blended with a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less, and subjected to a condensation polymerization reaction (second condensation polymerization reaction), whereby an amorphous polyester ( B) can be obtained.
Here, the carboxylic acid compounded in the first condensation polymerization reaction may contain a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less. Moreover, the carboxylic acid blended in the second polycondensation reaction may contain a carboxylic acid monomer larger than the second dissociation constant (pKa2) 5. However, in the first polycondensation reaction, among the raw materials of the amorphous polyester constituting the amorphous polyester (B), raw materials other than the dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less may be blended. preferable. In the second polycondensation reaction, it is preferable to mix a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less among the raw materials of the amorphous polyester constituting the amorphous polyester (B).
In the first polycondensation reaction, an esterification catalyst may be blended, and an esterification cocatalyst may be blended. Moreover, you may mix | blend a polymerization inhibitor at the time of a 2nd condensation polymerization reaction.

The reaction temperature of the first condensation polymerization reaction is preferably 210 ° C. or higher, more preferably 220 ° C. or higher, further preferably 230 ° C. or higher, preferably 250 ° C. or lower, more preferably 245 ° C. or lower, still more preferably. Is 240 ° C. or lower.
The reaction temperature of the second polycondensation reaction is preferably 180 ° C. or higher, more preferably 190 ° C. or higher, still more preferably 200 ° C. or higher, preferably 230 ° C. or lower, more preferably 220 ° C. or lower, still more preferably. Is 215 ° C. or lower.

[Esterification catalyst]
Examples of the esterification catalyst suitably used for the condensation polymerization include a titanium compound and a tin (II) compound having no Sn-C bond, and these may be used alone or in combination of two or more. it can.

As a titanium compound, the titanium compound which has a Ti-O bond is preferable, and the compound which has a C1-C28 alkoxy group, an alkenyloxy group, or an acyloxy group is more preferable.
Examples of the tin (II) compound having no Sn—C bond include a tin (II) compound having a Sn—O bond, a tin (II) compound having a Sn—X (X represents a halogen atom) bond, and the like. Preferred is a tin (II) compound having a Sn-O bond, and among them, di (2-ethylhexanoic acid) tin (II) is more preferable from the viewpoints of reactivity, molecular weight adjustment, and resin physical property adjustment. .

  The amount of the esterification catalyst is preferably from the viewpoint of reactivity, molecular weight adjustment and resin physical property adjustment to 100 parts by mass of the total amount of the alcohol component and carboxylic acid component of the crystalline polyester (A). 1 part by mass or more, more preferably 0.2 part by mass or more, further preferably 0.3 part by mass or more, still more preferably 0.5 part by mass or more, and preferably 3 parts by mass or less, more preferably 2 parts by mass or less, more preferably 1 part by mass or less.

[Esterification promoter]
The esterification cocatalyst need not be used, but may be used. As the esterification cocatalyst, a pyrogallol compound is preferred. This pyrogallol compound has a benzene ring in which three hydrogen atoms adjacent to each other are substituted with a hydroxyl group, and pyrogallol, gallic acid, gallic acid ester, 2,3,4-trihydroxybenzophenone, 2,2 ′ Benzophenone derivatives such as 3,3,4-tetrahydroxybenzophenone, catechin derivatives such as epigallocatechin and epigallocatechin gallate, and the like, and gallic acid is preferred from the viewpoint of reactivity.

(Polymerization inhibitor)
The polymerization inhibitor is not particularly limited, but 4-t-butylcatechol is preferable.

(Aqueous medium)
As described above, in Step I, an aggregate X containing resin particles containing crystalline polyester (A) and resin particles containing amorphous polyester (B) is obtained in an aqueous medium.
As the aqueous medium, those mainly containing water are preferable.
Examples of components other than water include aliphatic alcohols having 1 to 5 carbon atoms such as methanol, ethanol, isopropanol, and butanol; dialkyl (carbon numbers 1 to 3) ketones such as acetone and methyl ethyl ketone; and water such as cyclic ethers such as tetrahydrofuran. Examples include organic solvents that dissolve. Among these, from the viewpoint of preventing mixing into the toner, alcohol-based organic solvents such as methanol, ethanol, isopropanol, and butanol that do not dissolve the resin can be more preferably used.
The content of water in the aqueous medium is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and further preferably 100% by mass. The water is preferably deionized water or distilled water.

As described above, in the step I, the resin particles containing the crystalline polyester (A) and the resin particles containing the amorphous polyester (B) are aggregated in the aqueous medium to obtain an aggregate for core x And a resin particle containing the core agglomerate x and the amorphous polyester (C), wherein the resin particles containing the amorphous polyester for shell (C) are further mixed in the aqueous medium. And a step Ib of obtaining the aggregate X (the first aspect of the step I). The step Ib may be omitted (second aspect of step I). In that case, Step Ia and Step I have the same meaning, and the obtained aggregate is not the core aggregate x but the aggregate X.
Next, step Ia and step Ib will be described.

(Process Ia)
Step Ia is a step of obtaining the core aggregate x by aggregating the resin particles containing the crystalline polyester (A) and the resin particles containing the amorphous polyester (B) in the aqueous medium. is there.
The particles constituting the core aggregate x may include particles other than the resin particles containing the crystalline polyester (A) and the resin particles containing the amorphous polyester (B). Preferably it contains only seed particles. The content of the two kinds of particles in the particles constituting the core aggregate x is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and still more preferably 99%. It is at least mass%.

In Step Ia, an aqueous dispersion (a) obtained by dispersing resin particles containing crystalline polyester (A) in an aqueous medium is used as a supply source of resin particles containing crystalline polyester (A). It is preferable. Similarly, an aqueous dispersion (b) obtained by dispersing resin particles containing amorphous polyester (B) in an aqueous medium is used as a supply source of resin particles containing amorphous polyester (B). It is preferable to do.
It is preferable that the aqueous dispersion (a) and the aqueous dispersion (b) are mixed to obtain a mixed dispersion, and the resin particles are aggregated in the mixed dispersion to obtain the core aggregate x.
It is preferable to add a flocculant for efficient aggregation. In addition, aggregation may be performed after adding additives such as a coloring agent, a charge control agent, a release agent, a conductivity adjusting agent, a reinforcing filler such as a fibrous substance, an antioxidant, and an anti-aging agent. The additive can also be used as an aqueous dispersion.
Next, the aqueous dispersion (a), the aqueous dispersion (b) and the additive will be described.

≪Aqueous dispersion (a) ≫
This aqueous dispersion (a) can be suitably obtained by a method including a step of phase inversion emulsification by adding an aqueous medium and, if necessary, a surfactant to the crystalline polyester (A).
In addition, the aqueous dispersion (a) is obtained by mixing the crystalline polyester (A) and an organic solvent to obtain a mixture (Step 1), adding an aqueous medium to the mixture, phase-inverting and emulsifying the resin particles. A step of obtaining a crude dispersion (Step 2), a step of obtaining an aqueous dispersion of resin particles by distilling off the organic solvent from the crude dispersion (Step 3), and a surfactant mixed with the obtained aqueous dispersion It can manufacture suitably by passing through the process (process 4) to do. However, at least one of the steps 1, 3 and 4 may be omitted.
Next, steps 1 to 4 will be described.

[Step 1]
In step 1, the crystalline polyester (A) and an organic solvent are mixed to obtain a mixture.
From the viewpoint of improving the dispersibility of the crystalline polyester (A), the organic solvent is preferably 15.0 MPa ¹ when expressed by a solubility parameter (SP value: POLYMER HANDBOOK THIRD EDITION 1989 by John Wiley & Sons, Inc). ^{/ 2} or more, more preferably 16.0MPa ^1/2, and even more preferably at 17.0MPa ^1/2 or more, and preferably 26.0MPa ^1/2 or less, more preferably 24.0MPa ^1/2 or less More preferably, it is 22.0 MPa ^1/2 or less.

Specific examples include the following organic solvents. The parentheses on the right side of the name of the next organic solvent are SP values, and the unit is MPa ^1/2 . That is, specific examples include alcohol solvents such as ethanol (26.0), isopropanol (23.5), and isobutanol (21.5); acetone (20.3), methyl ethyl ketone (19.0), methyl Ketone solvents such as isobutyl ketone (17.2) and diethyl ketone (18.0); ether solvents such as dibutyl ether (16.5), tetrahydrofuran (18.6) and dioxane (20.5); Examples thereof include acetate solvents such as ethyl acetate (18.6) and isopropyl acetate (17.4). Among these, from the viewpoint of improving the dispersibility of the crystalline polyester (A), a ketone solvent and an acetate solvent are preferable, and at least one selected from the group consisting of methyl ethyl ketone, ethyl acetate, and isopropyl acetate is more preferable. Further, from the viewpoint of heat resistant storage stability of the toner, ethyl acetate and / or isopropyl acetate is more preferable, and ethyl acetate is still more preferable.

  The mass ratio of the organic solvent to the crystalline polyester (A) (organic solvent / crystalline polyester (A)) is preferably 0.03 or more, more preferably from the viewpoint of improving the dispersibility of the crystalline polyester (A). Is 0.05 or more, more preferably 0.1 or more, preferably 5 or less, more preferably 1.5 or less, still more preferably 1 or less, still more preferably 0.8 or less, and still more preferably. 0.6 or less.

Examples of the neutralizing agent used in the present invention include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; ammonia, trimethylamine, ethylamine, diethylamine, triethylamine, triethanolamine, and tributylamine. Of the organic base. Among these, from the viewpoint of obtaining a toner having excellent low-temperature fixability, heat-resistant storage stability and chargeability, a neutralizing agent having a pKa of 12 or less is preferable, a neutralizing agent having a pKa of 10 or less is more preferable, and the same From the viewpoint of the above, a neutralizer having a pKa of 8 or more is more preferable. Of these, ammonia (pKa = 9.3) and triethylamine (pKa = 9.8) are preferable, and ammonia is more preferable.
From the same viewpoint, the neutralization degree of the crystalline polyester (A) is preferably 60 mol% or more, more preferably 70 to 100 mol%, still more preferably 80 to 100 mol%, and still more preferably. It is 90-100 mol%, More preferably, it is 95-100 mol%. In addition, the neutralization degree (mol%) of resin can be calculated | required by a following formula.
Degree of neutralization = {[mass of neutralizer (g) / equivalent of neutralizer] / [[acid value of resin (mgKOH / g) × mass of resin (g)] / (56 × 1000)]} × 100

  In addition, you may add arbitrary components to a mixture in the range which does not affect the effect of this invention. Examples thereof include inorganic salts, organic solvents other than those described above, and surfactants described later.

The said mixture can be obtained by mixing the crystalline polyester (A) mentioned above, an organic solvent, and the neutralizing agent as needed.
In the method for producing the mixture, the order of adding the raw materials is not limited, but it is preferable to mix the neutralizing agent after mixing the crystalline polyester (A) and the organic solvent.
At the time of mixing, it is preferable to stir with a commonly used mixing and stirring device such as an anchor blade or an external circulation stirring device.

  The temperature at the time of mixing is preferably 5 ° C. or higher, more preferably 10 ° C. or higher, further preferably 20 ° C. or higher, from the viewpoints of stabilizing the process temperature, shortening the process time, and reducing the viscosity of the solution. The temperature is preferably 85 ° C. or lower, more preferably 80 ° C. or lower, and still more preferably 75 ° C. or lower. Further, the stirring is preferably performed until there is no significant phase separation or insoluble matter, and the stirring time depends on the stirring speed and temperature conditions, but is preferably 0.5 hours or more, more preferably It is 1 hour or longer, preferably 5 hours or shorter, more preferably 3 hours or shorter.

[Step 2]
Step 2 is a step of adding a water-based medium and, if necessary, a surfactant to the above mixture, and phase inversion emulsifying to obtain a crude dispersion of resin particles.
As the aqueous medium, those mainly containing water are preferable.
Examples of components other than water include aliphatic alcohols having 1 to 5 carbon atoms such as methanol, ethanol, isopropanol, and butanol; dialkyl (carbon numbers 1 to 3) ketones such as acetone and methyl ethyl ketone; and water such as cyclic ethers such as tetrahydrofuran. Examples include organic solvents that dissolve. Among these, from the viewpoint of preventing mixing into the toner, alcohol-based organic solvents such as methanol, ethanol, isopropanol, and butanol that do not dissolve the resin can be more preferably used.
From the viewpoint of improving the emulsion stability of the resin, the content of water in the aqueous medium is preferably 80% by mass or more, more preferably 90 to 100% by mass, still more preferably 95 to 100% by mass, and 100% by mass. Even more preferred. The water is preferably deionized water or distilled water.

The temperature at which the aqueous medium is added is preferably 20 ° C. or higher, more preferably 50 ° C. or higher, still more preferably 60 ° C. or higher, and even more preferably 65 ° C. or higher, from the viewpoint of improving the emulsion stability of the resin. Also, it is preferably 90 ° C. or lower, more preferably 85 ° C. or lower, still more preferably 80 ° C. or lower, and still more preferably 75 ° C. or lower.
Among these, from the viewpoint of improving the emulsion stability of the resin, the melting point of the crystalline polyester (A) or higher is preferable.
The addition rate of the aqueous medium is preferably 0.1 parts by mass / min with respect to 100 parts by mass of the crystalline polyester (A) until the phase inversion is completed from the viewpoint of obtaining resin composition particles having a small particle size. Or more, more preferably 0.5 parts by weight or more, further preferably 1 part by weight or more, still more preferably 3 parts by weight or more, still more preferably 4 parts by weight or more, Preferably it is 50 parts by weight or less, more preferably 30 parts by weight or less, more preferably 20 parts by weight or less, even more preferably 10 parts by weight or less, even more preferably 8 parts by weight or less. It is. There is no restriction | limiting in the addition rate of the aqueous medium after phase inversion.

The amount of the aqueous medium used is preferably 100 parts by mass or more with respect to 100 parts by mass of the crystalline polyester (A) from the viewpoint of obtaining a uniform aggregate (aggregate X or aggregate x) in the subsequent aggregation step. More preferably 150 parts by mass or more, still more preferably 200 parts by mass or more, still more preferably 300 parts by mass or more, still more preferably 400 parts by mass or more, and preferably 2000 parts by mass or less, more preferably 1500 parts by mass. Part or less, more preferably 1000 parts by weight or less, still more preferably 700 parts by weight or less, and still more preferably 500 parts by weight or less.
In addition, from the viewpoint of obtaining a uniform aggregate in the subsequent aggregation step, the aqueous medium is added so that the mass ratio of the aqueous medium to the organic solvent (aqueous medium / organic solvent) is 70/30 to 98/2. It is preferable to do. From this viewpoint, it is more preferably 80/20 or more, further preferably 85/15 or more, more preferably 95/15 or less, still more preferably 90/10 or less.

  Examples of the surfactant include nonionic surfactants, anionic surfactants, and cationic surfactants. Among these, from the viewpoint of dispersibility of the crystalline polyester (A), a nonionic surfactant and / or an anionic surfactant are preferable, and an anionic surfactant is more preferable.

  Nonionic surfactants include polyoxyethylene nonyl phenyl ether, polyoxyethylene oleyl ether, polyoxyethylene alkyl aryl ethers such as polyoxyethylene lauryl ether or polyoxyethylene alkyl ethers, polyethylene glycol monolaurate, Examples include polyoxyethylene fatty acid esters such as polyethylene glycol monostearate and polyethylene glycol monooleate, and oxyethylene / oxypropylene block copolymers. Among these, from the viewpoint of emulsion stability of the resin, polyoxyethylene alkyl ethers Is preferred.

Examples of the anionic surfactant include alkylbenzene sulfonates such as sodium alkylbenzene sulfonate, alkyl sulfates such as sodium alkyl sulfate, polyoxyalkylene alkyl ether sulfates such as sodium polyoxyalkylene alkyl ether sulfate, and the like. Among these, from the viewpoint of emulsion stability of the resin, sodium alkylbenzenesulfonate and polyoxyalkylene alkyl ether sulfate are preferable, and polyoxyalkylene alkyl ether sulfate is more preferable.
Examples of the cationic surfactant include alkyltrimethylammonium chloride and dialkyldimethylammonium chloride.
Of the surfactants, polyoxyethylene alkyl ethers and polyoxyalkylene alkyl ether sulfates are preferred from the viewpoint of dispersibility of the crystalline polyester (A) and emulsion stability of the resin, and polyoxyalkylene alkyl ether sulfates. Is more preferable.

[Step 3]
Step 3 is a step of obtaining an aqueous dispersion of resin particles by distilling off the organic solvent from the crude dispersion.
The method for removing the organic solvent is not particularly limited, and any method can be used. However, since it is dissolved in water, it is preferably distilled. Further, the organic solvent may not be completely removed and may remain in the aqueous dispersion. In this case, the residual amount of the organic solvent is preferably 1% by mass or less, more preferably 0.5% by mass or less, and still more preferably 0% by mass in the aqueous dispersion.

  When removing the organic solvent by distillation, it is preferable to raise the temperature to a temperature equal to or higher than the boiling point of the organic solvent to be used while stirring. Further, from the viewpoint of maintaining the dispersion stability of the crystalline polyester (A), it is more preferable to raise the temperature to a temperature equal to or higher than the boiling point of the organic solvent used under the reduced pressure and distill off. Note that the temperature may be increased after the pressure is reduced, or the pressure may be decreased after the temperature is increased. From the viewpoint of maintaining the dispersion stability of the crystalline polyester (A), it is preferable to distill off at a constant temperature and pressure.

[Step 4]
Step 4 is a step of mixing a surfactant with the obtained aqueous dispersion.
The amount of the surfactant added in the step 4 is preferably 50 mass of the total amount of the surfactant added in the steps 1 to 4 from the viewpoint of obtaining a toner having excellent low temperature fixability, heat resistant storage stability and chargeability. % Or more, more preferably 80 to 100% by mass, still more preferably 90 to 100% by mass, still more preferably 95 to 100% by mass, and still more preferably 99 to 100% by mass.
Further, the amount of the surfactant to be added in the step 4 is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, and more preferably 1 part by mass or more with respect to 100 parts by mass of the crystalline polyester (A) from the same viewpoint. Preferably it is 2 parts by mass or more, preferably 15 parts by mass or less, more preferably 10 parts by mass or less, and still more preferably 5 parts by mass or less.

When the surfactant is added, it is preferable to stir with a commonly used mixing and stirring device such as an anchor blade or an external circulation stirring device.
When a mixing stirring device such as an anchor blade is used, the peripheral speed of stirring is preferably 20 m / min or more, more preferably 40 m / min or more, still more preferably 60 m / min or more, and still more preferably, from the viewpoint of dispersibility. Is 80 m / min or more, preferably 200 m / min or less, more preferably 150 m / min or less, and still more preferably 100 m / min or less.

  The temperature at the time of addition of the surfactant in step 4 is preferably 5 ° C. or higher, more preferably 10 ° C. or higher, further preferably 20 ° C. or higher, from the viewpoint of dispersibility of the surfactant in water, etc. Preferably it is 50 degrees C or less, Preferably it is 40 degrees C or less, Preferably it is 35 degrees C or less.

  The solid content concentration of the aqueous dispersion obtained through the production process of the aqueous dispersion including Step 1 to Step 4 is preferably 3 by appropriately adding water from the viewpoint of the stability of the dispersion and ease of handling. It is at least 5 mass%, more preferably at least 5 mass%, even more preferably at least 15 mass%, preferably at most 40 mass%, more preferably at most 30 mass%, still more preferably at most 25 mass%.

The volume median particle diameter (D ₅₀ ) of the resin particles containing the crystalline polyester (A) in the obtained aqueous dispersion (a) is preferably 50 nm or more, more preferably from the viewpoint of toner productivity. 100 nm or more, more preferably 120 nm or more, still more preferably 130 nm or more, still more preferably 150 nm or more, preferably 300 nm or less, more preferably 250 nm or less, still more preferably 210 nm or less, and even more preferably 200 nm or less. More preferably, it is 195 nm or less.

<< Aqueous dispersion (b) >>
This aqueous dispersion (b) can be suitably produced in the same manner as the above aqueous dispersion (a) except that the amorphous polyester (B) is used instead of the crystalline polyester (A). .
The volume median particle diameter (D ₅₀ ) of the resin particles containing the amorphous polyester (B) in the obtained aqueous dispersion (b) is preferably 50 nm or more from the viewpoint of toner productivity. More preferably 70 nm or more, still more preferably 90 nm or more, still more preferably 100 nm or more, still more preferably 110 nm or more, preferably 250 nm or less, more preferably 220 nm or less, still more preferably 200 nm or less, and still more preferably Is 180 nm or less, more preferably 150 nm or less.

≪Flocculant≫
As the flocculant, a quaternary salt cationic surfactant, an organic flocculant such as polyethyleneimine; and an inorganic flocculant such as inorganic metal salt and inorganic ammonium salt are used. From the viewpoint of the particle size distribution of the toner, heat resistant storage stability and gloss of printed matter, an inorganic flocculant is preferable, and an inorganic metal salt is particularly preferable.
Examples of the inorganic metal salt include at least one of sodium sulfate, sodium chloride, calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, and aluminum chloride, preferably calcium chloride. The valence of the central metal of the inorganic metal salt is preferably divalent or higher from the viewpoint of the particle size distribution of the toner, heat resistant storage stability, and gloss of the printed matter.

In the case of adding a flocculant, the amount added is from the viewpoint of obtaining a toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability, and a resin particle and an amorphous composite resin containing the crystalline polyester (A) Preferably it is 0.001 mass part or more with respect to 100 mass parts of total amount of the resin particle containing (B), More preferably, it is 0.005 mass part or more, More preferably, it is 0.01 mass part or more, More preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, and preferably 10 parts by mass or less, more preferably 7 parts by mass or less, still more preferably 1 part by mass or less, still more preferably 0. 0.8 parts by mass or less, more preferably 0.5 parts by mass or less.
The flocculant is preferably added after being dissolved in an aqueous medium, and it is preferable that the flocculant is sufficiently stirred at the time of addition of the flocculant and after completion of the addition.

In the aggregation step, the solid content concentration in the system is preferably 1% by mass or more, more preferably 5% by mass or more, and further preferably 10% by mass or more, in order to cause uniform aggregation. It is 50 mass% or less, More preferably, it is 40 mass% or less, More preferably, it is 30 mass% or less.
In the coagulation step, from the viewpoint of uniformly dispersing the coagulant and causing uniform coagulation, the temperature during addition of the coagulant is preferably 10 ° C or higher, more preferably 15 ° C or higher, and further preferably 18 ° C or higher. Further, it is preferably 40 ° C. or lower, more preferably 35 ° C. or lower, and further preferably 30 ° C. or lower. The holding temperature after adding the flocculant is preferably 40 ° C. or higher, more preferably 45 ° C. or higher, still more preferably 47 ° C. or higher, preferably 65 ° C. or lower, more preferably 60 ° C. or lower, still more preferably. Is 55 ° C. or lower.

≪Colorant≫
There is no restriction | limiting in particular as a coloring agent, A well-known coloring agent is mentioned, According to the objective, it can select suitably. Specifically, carbon black, inorganic composite oxide, chrome yellow, hansa yellow, benzidine yellow, selenium yellow, quinoline yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, permanent red, brilliantamine 3B, Brilliantamine 6B, DuPont Oil Red, Pyrazolone Red, Resol Red, Rhodamine B Lake, Lake Red C, Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Phthalocyanine Green, Malachite Green Oxalate, etc. Various pigments: acridine, xanthene, azo, benzoquinone, azine, anthraquinone, indico, Indigo dyes, phthalocyanine, aniline black, polymethine, triphenylmethane dyes, diphenylmethane dyes, thiazine, and include various dyes of thiazole, and the like. These can be used alone or in combination of two or more.

From the viewpoint of improving the image quality, the addition amount of the colorant is preferably based on 100 parts by mass of the total amount of the resin particles containing the crystalline polyester (A) and the resin particles containing the amorphous polyester (B). 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, still more preferably 1.0 parts by mass or more, still more preferably 2.0 parts by mass or more, and preferably 20 parts by mass or less, more Preferably it is 10 mass parts or less, More preferably, it is 8 mass parts or less, More preferably, it is 5 mass parts or less.
This colorant may be added as a colorant dispersion containing colorant fine particles. The volume median particle size (D ₅₀ ) of the colorant fine particles is preferably 50 nm or more, more preferably 100 nm or more, and preferably 200 nm or less, more preferably 150 nm or less.

≪Charge control agent≫
Examples of charge control agents include chromium azo dyes, iron azo dyes, aluminum azo dyes, and salicylic acid metal complexes. Various charge control agents may be used alone or in combination of two or more.
When the charge control agent is added, the addition amount is 100 masses in total of resin particles containing the crystalline polyester (A) and the resin particles containing the amorphous composite resin (B) from the viewpoint of improving the image quality. Is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, still more preferably 0.5 parts by mass or more, still more preferably 0.6 parts by mass or more, and preferably Is 8 parts by mass or less, more preferably 7 parts by mass or less, still more preferably 5 parts by mass or less, and still more preferably 2 parts by mass or less.
The charge control agent may be added as a charge control agent dispersion containing charge control agent fine particles. The volume median particle size (D ₅₀ ) of the charge control agent fine particles is preferably 100 nm or more, more preferably 300 nm or more, and preferably 800 nm or less, more preferably 500 nm or less.

(Process Ib)
In step Ib, the resin particles containing the shell amorphous polyester (C) are further mixed in the aqueous medium, and the core aggregate x and the resin particles containing the amorphous polyester (C) are aggregated. In this step, the aggregate X is obtained.
That is, the core aggregate x containing the resin particles containing the crystalline polyester (A) and the resin particles containing the amorphous polyester (B) is present in the aqueous medium by the step Ia. In step Ib, resin particles containing the amorphous polyester for shell (C) are further mixed in the aqueous medium containing the aggregate for core x, and the core aggregate x and the amorphous for shell are mixed. The resin particles containing polyester (C) are aggregated. As a result, the amorphous polyester for shell (C) adheres to the outermost surface of the core aggregate x, and the aggregate comprises the core aggregate x and the amorphous polyester for shell (C) covering the surface. Get X.

The particles constituting the aggregate X may include particles other than the resin particles containing the amorphous polyester for shell (C), but only the resin particles containing the amorphous polyester for shell (C). It is preferable to contain. The content of the resin particles containing the shell amorphous polyester (C) in the particles constituting the aggregate X is preferably 80% by mass or more, more preferably 90% by mass or more, and still more preferably 95% by mass. As mentioned above, More preferably, it is 99 mass% or more.
After aggregation, an aggregation terminator may be added as necessary. In addition, when using an aggregation terminator, it is preferable to use a surfactant as the aggregation terminator, and it is more preferable to use an anionic surfactant. Of the anionic surfactants, it is more preferable to use at least one selected from the group consisting of alkyl ether sulfates, alkyl sulfates, and linear alkylbenzene sulfonates, and it is more preferable to use alkyl ether sulfates. .

≪Resin particles containing amorphous polyester for shell (C) ≫
The resin particles containing the amorphous polyester for shell (C) may contain components other than the amorphous polyester for shell (C) as long as the effects of the present invention are not impaired. From the viewpoint of obtaining a toner for developing an electrostatic charge image that has both good heat storage stability and excellent chargeability, it is preferable not to contain any components other than the amorphous polyester for shell (C). The content of the amorphous polyester for shell (C) in the resin particles containing the amorphous polyester for shell (C) is preferably 80% by mass or more, more preferably 90 to 100% by mass, and still more preferably 95%. It is -100 mass%, More preferably, it is 99-100 mass%, More preferably, it is substantially 100 mass%.

The volume median particle size of the resin particles containing the amorphous polyester for shell (C) is preferably from the viewpoint of easy aggregation, a toner having excellent low temperature fixability, heat resistant storage stability and chargeability. 10 nm or more, more preferably 50 nm or more, more preferably 100 nm or more, still more preferably 110 nm or more, preferably 200 nm or less, more preferably 150 nm or less, still more preferably 140 nm or less, still more preferably 130 nm or less. is there.
The resin particles containing the amorphous polyester for shell (C) can be suitably produced by adding an aqueous medium to the amorphous polyester for shell (C) and performing phase inversion emulsification.
As a supply source of the resin particles containing the amorphous polyester for shell (C), an aqueous dispersion (c) in which the resin particles containing the amorphous polyester for shell (C) are dispersed in an aqueous medium. Is preferably used.
The aqueous dispersion (c) is preferably produced in the same manner as the aqueous dispersion (a) except that the amorphous polyester (C) for shell is used instead of the crystalline polyester (A). Can do.

≪Amorphous polyester for shell (C) ≫
The amorphous polyester for shell (C) is obtained by condensation polymerization of a carboxylic acid component and an alcohol component.

  Examples of the carboxylic acid component of the amorphous polyester for shell (C) include aliphatic dicarboxylic acid, aromatic dicarboxylic acid, and trivalent or higher polyvalent carboxylic acid. One of aliphatic dicarboxylic acid and aromatic dicarboxylic acid or It is preferable that both are included, and it is more preferable that both are included. Further, acid anhydrides of these carboxylic acids and alkyl (1 to 3 carbon atoms) esters thereof may be used. These carboxylic acid components can be used alone or in combination of two or more.

Specific examples of the aromatic dicarboxylic acid include terephthalic acid, phthalic acid, and isophthalic acid. Among these, terephthalic acid is preferable from the viewpoint of obtaining a toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability.
The content of the aromatic dicarboxylic acid is preferably 20 mol% or more, more preferably 30 mol% or more in the carboxylic acid component from the viewpoint of obtaining a toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability. More preferably, it is 80 mol% or more, More preferably, it is 90 mol% or more, Preferably it is 99 mol% or less, More preferably, it is 97 mol% or less, More preferably, it is 95 mol% or less.
The aliphatic dicarboxylic acid preferably contains an aliphatic dicarboxylic acid having 2 to 6 carbon atoms.

  Specific examples of the aliphatic dicarboxylic acid include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, and dodecanedioic acid. Can be mentioned. Examples of the aliphatic dicarboxylic acid include succinic acid substituted with an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms such as dodecyl succinic acid, dodecenyl succinic acid, and octenyl succinic acid. . Among these, fumaric acid, dodecenyl succinic acid, and octenyl succinic acid are preferable, and fumaric acid and dodecenyl succinic acid are more preferable from the viewpoint of obtaining a toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability.

  From the same viewpoint, the content of the aliphatic dicarboxylic acid is preferably 1 mol% or more, more preferably 2 mol% or more, still more preferably 3 mol% or more, still more preferably 5 mol% or more in the carboxylic acid component. Moreover, it is preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 20 mol% or less, and still more preferably 10 mol% or less.

Examples of the alcohol component that is a raw material monomer of the amorphous polyester for shell (C) include aliphatic diols, aromatic diols, and trihydric or higher polyhydric alcohols, and aromatic diols are preferred. These alcohol components can be used alone or in combination of two or more.
The alcohol component of the amorphous polyester for shell (C) is an alkylene oxide of bisphenol A represented by the above formula (I) from the viewpoint of obtaining a toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability. It is preferable to contain an adduct.

As the alkylene oxide adduct of bisphenol A represented by the above formula (I), specifically, a polyoxypropylene adduct of 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4- Hydroxyphenyl) propane polyoxyethylene adduct and the like.
The alkylene oxide adduct of bisphenol A represented by the formula (I) is preferably an alcohol component, preferably 70 mol% or more, from the viewpoint of obtaining a toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability. It is contained in an amount of not more than mol%, more preferably not less than 80 mol% and not more than 100 mol%, still more preferably not less than 90 mol% and not more than 100 mol%.

  The ratio of the carboxylic acid component to 100 mol parts of the alcohol component which is the raw material monomer of the amorphous polyester for shell (C) is preferably 80 mol parts or more, more preferably 85 mol parts or more, from the viewpoint of reactivity and physical property adjustment. More preferably, it is 90 mol parts or more, still more preferably 95 mol parts or more, and preferably 115 mol parts or less, more preferably 110 mol parts or less, still more preferably 105 mol parts or less.

  The softening point of the amorphous polyester (C) for the shell is from the standpoint of obtaining a toner having higher heat resistance of the shell portion of the toner than the core portion, achieving both low-temperature fixability and heat-resistant storage stability and excellent chargeability. It is preferably higher than the softening point of the crystalline polyester (A). From this viewpoint, the temperature difference between the softening points of the amorphous polyester for shell (C) and the crystalline polyester (A) is preferably 5 ° C. or higher, more preferably 10 ° C. or higher, and still more preferably 15 ° C. or higher. More preferably, it is 20 ° C or higher, more preferably 25 ° C or higher, preferably 50 ° C or lower, more preferably 40 ° C or lower, still more preferably 34 ° C or lower, still more preferably 32 ° C or lower, and still more preferably. Is 30 ° C. or lower.

The softening point of the amorphous polyester for shell (C) is preferably 85 ° C. or higher, more preferably 90 ° C. or higher, still more preferably 95 ° C. or higher, still more preferably 100 ° C. or higher, even more preferably 105 ° C. or higher. Also, it is preferably 140 ° C. or lower, more preferably 135 ° C. or lower, still more preferably 130 ° C. or lower, still more preferably 120 ° C. or lower, and still more preferably 115 ° C. or lower.
Further, from the same viewpoint, the glass transition temperature of the amorphous polyester for shell (C) is preferably 45 ° C. or higher, more preferably 50 ° C. or higher, still more preferably 55 ° C. or higher, and still more preferably 60 ° C. or higher. Also, it is preferably 85 ° C. or lower, more preferably 80 ° C. or lower, still more preferably 75 ° C. or lower, and still more preferably 70 ° C. or lower.

  From the same viewpoint, the glass transition temperature of the amorphous polyester for shell (C) is preferably higher than the glass transition temperature of the amorphous polyester (B), and the temperature difference is preferably 15 ° C. As mentioned above, More preferably, it is 20 degreeC or more, Preferably it is 30 degrees C or less, More preferably, it is 25 degrees C or less.

  From the same viewpoint, the acid value of the amorphous polyester for shell (C) is preferably 1 mgKOH / g or more, more preferably 5 mgKOH / g or more, still more preferably 10 mgKOH / g or more, still more preferably 12 mgKOH / g. In addition, it is preferably 40 mgKOH / g or less, more preferably 35 mgKOH / g or less, still more preferably 20 mgKOH / g or less, and still more preferably 18 mgKOH / g or less.

<Process II>
Step II is a step of fusing the aggregate X.
The temperature in the system in Step II is the target toner particle size, particle size distribution, shape control and particle fusing viewpoint, low temperature fixability and heat storage stability, and a toner with excellent chargeability Therefore, it is preferably 70 ° C. or higher, more preferably 75 ° C. or higher, and preferably 100 ° C. or lower, more preferably 90 ° C. or lower. The stirring speed is preferably a speed at which the aggregate X does not settle.

<Post process>
By appropriately subjecting the fused particles obtained in step II to a solid-liquid separation step such as filtration, a washing step, and a drying step, the electrostatic image developing toner of the present invention can be suitably obtained.
In the washing step, it is preferable to completely remove the added nonionic surfactant by washing, and washing with an aqueous solution below the cloud point of the nonionic surfactant is preferred. The washing is preferably performed a plurality of times.
In the drying step, any method such as a vibration type fluidized drying method, a spray drying method, a freeze drying method, a flash jet method, or the like can be employed. The water content after drying of the toner is preferably adjusted to 1.5% by mass or less, more preferably 1.0% by mass or less, from the viewpoint of chargeability.
Further, an external additive may be added for the purpose of improving fluidity. Examples of the external additive include silica fine particles whose surface is hydrophobized, titanium oxide fine particles, alumina fine particles, cerium oxide fine particles, and inorganic fine particles such as carbon black; polymer fine particles such as polycarbonate, polymethyl methacrylate, and silicone resin, and the like. Fine particles can be used.

The number average particle diameter of the external additive is preferably 4 to 200 nm, more preferably 8 to 30 nm, from the viewpoint of the fluidity of the toner.
When the external additive is added, the addition amount is preferably 0 with respect to 100 parts by mass of the toner before the processing with the external additive, from the viewpoint of the fluidity of the toner, the environmental stability of the charging degree, and the storage stability. .1 part by mass or more, more preferably 0.2 part by mass or more, further preferably 0.5 part by mass or more, still more preferably 1 part by mass or more, and preferably 8 parts by mass or less, more preferably 5 parts by mass. It is not more than part by mass, more preferably not more than 4 parts by mass, still more preferably not more than 3 parts by mass.

The volume median particle diameter (D ₅₀ ) of the toner is preferably 3.0 μm or more, more preferably 3.5 μm or more, and still more preferably 4.0 μm or more, from the viewpoint of heat resistant storage stability, durability and low-temperature fixability of the toner. More preferably, it is 4.5 μm or more, preferably 8.5 μm or less, more preferably 8.0 μm or less, still more preferably 7.5 μm or less, still more preferably 7.0 μm or less, and still more preferably. 5.0 μm or less.

Further, from the same viewpoint, the coefficient of variation (CV value) (%) in the particle size distribution of the toner is preferably 40% or less, more preferably 35% or less, and further preferably 30% or less. From the viewpoint of improving productivity, 5% or more is preferable, 10% or more is more preferable, and 15% or more is still more preferable. In addition, CV value is a value represented by the following formula, and is calculated | required by the method as described in an Example.
CV value (%) = [standard deviation of particle size distribution (μm) / volume median particle size (μm)] × 100

[Toner for electrostatic image development]
The electrostatic image developing toner of the present invention can be produced by the production method described above.
By adopting the first aspect of the above-mentioned step I (implementing steps Ia and Ib), a core-shell type electrostatic image developing toner containing the shell amorphous polyester (C) in the shell portion can be obtained. it can. Further, by adopting the second aspect of the above-mentioned step I (implementing step Ia), a non-core-shell (single structure) electrostatic charge image developing toner can be obtained.

  Mass ratio of total amount of crystalline polyester (A) and amorphous polyester (B) to amorphous polyester (C) for shell [total amount of crystalline polyester (A) and amorphous polyester (B) / for shell Amorphous polyester (C)] is preferably 60/40 or more, more preferably 70/30 or more, and still more preferably 80 from the viewpoint of obtaining a toner having both low-temperature fixability and heat-resistant storage stability and excellent chargeability. / 20 or more, more preferably 85/15 or more, preferably 100/0 or less, more preferably 99/1 or less, still more preferably 95/5 or less, and still more preferably 90/10 or less. .

In relation to the above-described embodiment, the present invention discloses the following method for producing an electrostatic image developing toner and electrostatic image developing toner.
[1] The proportion of carboxy groups derived from dicarboxylic acid monomers having a second dissociation constant (pKa2) of 5 or less among carboxy groups at the end of the polyester chain is 70 mol% or more, preferably 72 mol% or more, more preferably Is 75 mol% or more, more preferably 78 mol% or more, and preferably 100 mol% or less, preferably 95 mol% or less, more preferably 92 mol% or less, still more preferably 90 mol% or less. Step I to obtain an agglomerate X containing a resin particle containing a reactive polyester (A) and a resin particle containing an amorphous polyester (B) in an aqueous medium, and fusing the agglomerate X A process for producing a toner for developing an electrostatic charge image, comprising Step II.

[2] The electrostatic image developing toner according to [1], wherein the dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less is a dicarboxylic acid compound having an unsaturated bond adjacent to the carboxy group. Production method.
[3] The electrostatic image development according to [1], wherein the dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less is one or more selected from fumaric acid, terephthalic acid, isophthalic acid and oxalic acid. Of manufacturing toner.
[4] The electrostatic charge image development according to any one of [1] to [3], wherein 70 mol% or more of the carboxylic acid monomer forming the inside of the polyester chain of the crystalline polyester (A) is a saturated aliphatic dicarboxylic acid. Of manufacturing toner.
[5] The method for producing a toner for developing an electrostatic charge image according to claim 4, wherein the saturated aliphatic dicarboxylic acid is at least one of succinic acid, adipic acid, sebacic acid and dodecanedioic acid.

[6] Of the carboxy group at the end of the polyester chain of the amorphous polyester resin (B), the proportion of the carboxy group derived from the dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less is 70 mol% or more. More preferably 72 mol% or more, still more preferably 75 mol% or more, still more preferably 78 mol% or more, more preferably 98 mol% or less, still more preferably 90 mol% or less, and still more preferably. The method for producing a toner for developing an electrostatic charge image according to any one of [1] to [5], which is 85 mol% or less.
[7] The melting point of the crystalline polyester (A) is 55 to 95 ° C., preferably 60 ° C. or higher, more preferably 70 ° C. or higher, still more preferably 75 ° C. or higher, still more preferably 79 ° C. or higher, and still more preferably. 80 ° C. or higher, preferably 100 ° C. or lower, more preferably 95 ° C. or lower, still more preferably 90 ° C. or lower, still more preferably 85 ° C. or lower, and still more preferably 82 ° C. or lower. [6] The method for producing a toner for developing an electrostatic image according to any one of [6].
[8] In step I, the aqueous dispersion (a) in which the resin particles containing the crystalline polyester (A) are dispersed in the aqueous medium and the resin particles containing the amorphous polyester (B) in the aqueous medium The method for producing a toner for developing an electrostatic charge image according to any one of [1] to [7], wherein the aqueous dispersion (b) dispersed therein is used.
[9] The electrostatic image developing image according to [8], wherein the aqueous dispersion (a) is obtained by a method including a step of adding an aqueous medium to the crystalline polyester (A) and phase inversion emulsification. Toner manufacturing method.
[10] A step in which the aqueous dispersion (a) is mixed with the crystalline polyester (A) and an organic solvent to obtain a mixture (Step 1), an aqueous medium is added to the mixture, and phase inversion emulsification is performed to obtain resin particles. It is obtained by a method comprising a step of obtaining a crude dispersion (Step 2) and a step of obtaining an aqueous dispersion of resin particles by distilling off the organic solvent from the crude dispersion (Step 3). [8] Or the manufacturing method of the electrostatic image developing toner as described in [9].

[11] The crystalline polyester (A) is obtained through a production method including a step of reacting a precursor crystalline polyester with a dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less, [1 ] The manufacturing method of the electrostatic image developing toner in any one of [10].
[12] The method for producing a toner for developing an electrostatic charge image according to [11], wherein a reaction rate in the condensation polymerization between the carboxylic acid component and the alcohol component of the precursor crystalline polyester is 95% or more.
[13] The aqueous dispersion (a) is obtained by a method comprising a step of adding a water-based medium and a surfactant to the crystalline polyester (A) and phase inversion emulsifying, [8] or [9] A method for producing a toner for developing an electrostatic image as described in 1.
[14] The method for producing a toner for developing an electrostatic charge image according to [10], further comprising a step 4 of mixing a surfactant with the aqueous dispersion obtained in the step 3.
[15] In step 2, the mass ratio of the aqueous medium to the organic solvent (aqueous medium / organic solvent) is preferably 70/30 to 98/2, more preferably 80/20 or more, and still more preferably 85. The electrostatic charge image according to [10] or [14], wherein the aqueous medium is added so as to be not less than / 15, more preferably not more than 95/15, and still more preferably not more than 90/10. A method for producing a developing toner.

[16] In step I, the resin particles containing the crystalline polyester (A) and the resin particles containing the amorphous polyester (B) are aggregated in the aqueous medium to obtain the core aggregate x. Step Ia to be obtained and resin particles containing the amorphous polyester for shell (C) are further mixed in the aqueous medium, and the resin particles containing the core aggregate x and the amorphous polyester (C) are obtained. The method for producing a toner for developing an electrostatic charge image according to any one of [1] to [15], comprising the step Ib of aggregating to obtain the aggregate X.
[17] An electrostatic image developing toner obtained by the production method of any one of [1] to [16].

  Each property such as resin, resin particles, and toner was measured and evaluated by the following method.

[Acid value of resin]
The acid value of the resin was measured based on the method of JIS K 0070. However, only the measurement solvent was changed from the mixed solvent of ethanol and ether specified in JIS K 0070 to a mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

[Resin softening point, glass transition temperature, etc.]
(1) Softening point Using a flow tester “CFT-500D” (manufactured by Shimadzu Corporation), a 1 g sample was heated at a heating rate of 6 ° C./min, and a load of 1.96 MPa was applied by a plunger. The nozzle was extruded from a nozzle having a diameter of 1 mm and a length of 1 mm. The amount of plunger drop of the flow tester was plotted against the temperature, and the temperature at which half of the sample flowed out was taken as the softening point.
(2) Maximum temperature of endothermic peak Using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan Co., Ltd.) 0 The sample cooled to 0 ° C. was allowed to stand for 1 minute as it was, and then measured while raising the temperature to 180 ° C. at a heating rate of 10 ° C./min. Of the endothermic peaks observed, the peak temperature on the highest temperature side was defined as the highest endothermic peak temperature.

(3) Melting point Using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of a sample was weighed into an aluminum pan and up to 200 ° C. The temperature was raised, and the temperature was cooled to 0 ° C. at a temperature lowering rate of 10 ° C./min. Next, the measurement was performed while increasing the temperature to 150 ° C. at a temperature increase rate of 10 ° C./min. Of the endothermic peaks observed, the temperature of the peak with the largest peak area was taken as the melting point.
(4) Glass transition temperature Using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of a sample is weighed into an aluminum pan, and 200 The temperature was raised to 0 ° C., and the temperature was cooled to 0 ° C. at a rate of temperature drop of 10 ° C./min. Next, the measurement was performed while increasing the temperature to 150 ° C. at a temperature increase rate of 10 ° C./min. The glass transition temperature was defined as the temperature at the intersection of the base line extension below the maximum temperature of the endothermic peak and the tangent line indicating the maximum slope from the peak rising portion to the peak apex.
(5) Crystallinity Index The ratio between the softening point and the maximum endothermic peak temperature measured as described above, that is, “softening point / maximum endothermic peak temperature” was calculated and used as the crystallinity index.

[Percentage of carboxy groups derived from dicarboxylic acid monomers having a pKa2 of 5 or less of the carboxy groups at the ends of the polyester chain of the resin]
A ¹³ C NMR spectrum is measured under the following conditions to identify and quantify the type of carboxylic acid monomer that forms a carboxy group at the end of the polyester chain. The proportion of carboxy groups attributed to the monomer was calculated.
・ Measuring machine: Mercury-400 (Varian)
-Observation nucleus: ¹³ C
・ Resin sample: 1g
・ Measurement solvent: ₃ mL of CDCl 3
・ Magnetic field strength: 14.09637 [T] (600 [MHz])
・ Number of scans: 6400
-Relaxation time: 15 seconds

[Proportion of saturated aliphatic dicarboxylic acid monomer (mol%) in the carboxylic acid monomer forming the inside of the polyester chain of the polyester]
The ¹³ C NMR spectrum was measured under the above conditions, the type of the carboxylic acid monomer forming the inside of the polyester chain was identified and quantified, and the ratio of the saturated aliphatic dicarboxylic acid monomer in the carboxylic acid monomer forming the inside of the polyester chain of the polyester Was calculated.

[Volume Median Particle Size (D ₅₀ ) of Aggregates]
The volume median particle size of the aggregate was measured as follows.
・ Measuring machine: "Coulter Multisizer III" (Beckman Coulter, Inc.)
・ Aperture diameter: 50μm
・ Analysis software: “Multisizer III version 3.51” (manufactured by Beckman Coulter)
・ Electrolyte: “Isoton II” (Beckman Coulter, Inc.)
-Dispersion: Polyoxyethylene lauryl ether "Emulgen 109P" (manufactured by Kao Corporation, HLB: 13.6) was dissolved in the electrolytic solution to obtain a dispersion having a concentration of 5% by mass.
Dispersion condition: 10 mg of sample (converted to solid content) is added to 5 mL of the dispersion, and dispersed for 1 minute with an ultrasonic disperser, then 25 mL of electrolyte is added, and further for 1 minute with an ultrasonic disperser. A sample dispersion was prepared by dispersing.
Measurement conditions: The sample dispersion is added to 100 mL of the electrolytic solution to adjust the particle size of 30,000 particles to a concentration that can be measured in 20 seconds, and then 30,000 particles are measured and the particle size distribution thereof. From this, the volume median particle size (D ₅₀ ) was determined.

[Volume Median Particle Size (D ₅₀ ) and CV Value of Resin Particles, Colorant Particles, Charge Control Agent Particles, and Release Agent Particles]
(1) Measuring apparatus: Laser diffraction particle size measuring instrument “LA-920” (manufactured by Horiba, Ltd.)
(2) Measurement conditions: Distilled water was added to the measurement cell, and the volume-median particle size (D ₅₀ ) was measured at a concentration at which the absorbance was in an appropriate range.

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

[Solid content concentration of aqueous dispersion, colorant dispersion, charge control agent dispersion and release agent particles]
Using an infrared moisture meter “FD-230” (manufactured by Kett Science Laboratory), a sample 5 g was dried at a temperature of 150 ° C. and in a measurement mode 96 (monitoring time 2.5 minutes / variation width 0.05%). The sample was dried and the moisture content (% by mass) of the sample was measured. The solid content was calculated according to the following formula.
Solid content concentration (% by mass) = 100-M
M: moisture (mass%) of sample = [(W−W0) / W] × 100
W: Sample mass before measurement (initial sample mass)
W0: Sample weight after measurement (absolute dry weight)

[Low-temperature fixability of toner]
The toner was mounted on an apparatus in which the fixing machine of the copying machine “AR-505” (manufactured by Sharp Corporation) was improved so that fixing outside the apparatus was possible, and a printed matter was obtained in an unfixed state (printing area: 2 cm × 12 cm, adhesion amount: 0.5 mg / cm ² ). After that, using a fixing machine (fixing speed 300 mm / sec) adjusted so that the total fixing pressure becomes 40 kgf, the fixing roll temperature is gradually increased from 80 ° C. to 240 ° C. by 5 ° C., and unfixed at each temperature. A fixing test of the printed matter in the state was performed. A cellophane adhesive tape “UNICEF cellophane” (manufactured by Mitsubishi Pencil Co., Ltd., width: 18 mm, JIS Z1522) is attached to the image portion of the printed matter, and the fixing is set at 30 ° C., separate from the fixing roll of the fixing machine. After passing through a roller, the tape was peeled off. The optical reflection density before and after the tape was peeled was measured using a reflection densitometer “RD-915” (manufactured by Gretag Macbeth Co.), and the ratio between the two (after peeling / before sticking × 100) was initially 90%. The temperature of the fixing roll exceeding the temperature was set as the minimum fixing temperature. The lower the minimum fixing temperature, the better the low temperature fixing property. As the fixing paper, “CopyBond SF-70NA” (manufactured by Sharp Corporation, 75 g / m ² ) was used.

[Heat resistant storage stability of toner]
10 g of toner was put in a 25 mL container (diameter: about 3 cm) and left for 72 hours in an environment of a temperature of 60 ° C. and a humidity of 80%. After standing for 48 hours, the degree of toner aggregation was visually observed every 12 hours, and the heat resistant storage stability was evaluated according to the following evaluation criteria. The longer the time during which no aggregation is observed, the better the heat resistant storage stability.
(Evaluation criteria)
A: Aggregation is not observed even after 72 hours.
B: Aggregation is not observed after 60 hours, but aggregation is observed after 72 hours.
C: Aggregation is not observed after 48 hours, but aggregation is observed after 60 hours.
D: Aggregation is observed after 48 hours.

[Toner chargeability]
At 50 ° C. and 50% relative humidity, 2.1 g of toner and 27.9 g of a silicone ferrite carrier (manufactured by Kanto Denka Kogyo Co., Ltd., average particle size: 40 μm) and a 50 cc cylindrical polypropylene bottle (manufactured by Nikko Corporation) ) And shaken 10 times vertically and horizontally, and then mixed at a speed of 90 r / min using a tumbler mixer and mixed for 1 hour. The charge amount at that time was measured using a q / m meter (manufactured by EPPING). The higher the absolute value of the charge amount,
Good chargeability.
Measurement equipment, settings, etc. are as follows.
Measuring instrument: q / m-meter manufactured by EPPING
Setting: Mesh size: 635 mesh (opening: 24 μm, made of stainless steel)
・ Soft blow, blow pressure (1000V)
• Suction time: 90 seconds • Charge amount (μC / g) = Total amount of electricity after 90 seconds (μC) / Amount of toner sucked (g)

[Manufacture of polyester, etc.]
Production Examples 1-4
(Production of crystalline polyesters A-1 to A-4)
The raw material monomer of polyester other than fumaric acid and the esterification catalyst shown in Table 1 are put into a 10-liter four-necked flask equipped with a thermometer, a stainless steel stirring bar, a flow-down condenser and a nitrogen inlet tube, and the atmosphere is put into a nitrogen atmosphere. In a mantle heater, the temperature was raised from 130 ° C. to 210 ° C. over 10 hours, and then the reaction was carried out at 210 ° C. to confirm that the reaction rate reached 95% or more. Then, after making it react at 210 degreeC and pressure reduction of 8 kPa for 1 hour, it cooled to 180 degreeC. Thereafter, fumaric acid and a radical polymerization inhibitor (4-t-butylcatechol) shown in Table 1 were added, and the temperature was raised to 210 ° C. over 2 hours. Then, after reacting at 210 degreeC for 1 hour, it reacted until it reached the acid value of Table 1 at 8 kPa, and crystalline polyester A-1 to A-4 was obtained. The physical properties of the resin are shown in Table 1. In addition, the reaction rate in this invention means the value of the amount of generated water (mol) / theoretical amount of generated water (mol) x100.

Production Example 5
(Production of crystalline polyester A-5)
The raw material monomer of polyester other than isophthalic acid and the esterification catalyst shown in Table 1 are put into a 10-liter four-necked flask equipped with a thermometer, a stainless steel stirring bar, a flow-down condenser and a nitrogen inlet tube, and the atmosphere is put into a nitrogen atmosphere. In a mantle heater, the temperature was raised from 130 ° C. to 210 ° C. over 10 hours, and then the reaction was carried out at 210 ° C. to confirm that the reaction rate reached 95% or more. Then, after making it react at 210 degreeC and pressure reduction of 8 kPa for 1 hour, it cooled to 180 degreeC. Thereafter, isophthalic acid and a radical polymerization inhibitor (4-t-butylcatechol) shown in Table 1 were added, and the temperature was raised to 235 ° C. over 1 hour. Then, after reacting at 235 degreeC for 5 hours, it reacted until it reached the acid value of Table 1 at 8 kPa, and crystalline polyester A-5 was obtained. The physical properties of the resin are shown in Table 1.

Production Example 6
(Production of crystalline polyester B-1)
The total amount of 1,10-decanediol, the total amount of succinic acid, equivalent to 35 parts of fumaric acid (1369 g), esterification catalyst, radical polymerization inhibitor (4-t-butylcatechol) shown in Table 2, thermometer, stainless steel stirring Place in a 10-liter four-necked flask equipped with a rod, a down-flow condenser and a nitrogen inlet tube, heat in a mantle heater in a nitrogen atmosphere from 130 ° C. to 210 ° C. over 10 hours, and then react at 210 ° C. It was confirmed that the reaction rate reached 95% or more. Then, after making it react at 210 degreeC and pressure reduction of 8 kPa for 1 hour, it cooled to 180 degreeC. Thereafter, the remaining 35 parts (1369 g) of fumaric acid shown in Table 2 was added, and the temperature was raised to 210 ° C. over 2 hours. Then, after reacting at 210 ° C. for 1 hour, the reaction was performed at 8 kPa until the acid values shown in Table 2 were reached, to obtain crystalline polyester B-1. The physical properties of the resin are shown in Table 1. In addition, the reaction rate in this invention means the value of production | generation reaction water amount (mol) / theoretical production | generation water amount (mol) x100.

Production Example 7
(Production of crystalline polyester B-2)
The polyester raw material monomer, esterification catalyst and radical polymerization inhibitor shown in Table 2 were placed in a 10-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser and a nitrogen inlet tube, and a nitrogen atmosphere The temperature was raised from 180 ° C. to 210 ° C. over 6 hours in a mantle heater. Then, it reacted until it reached the acid value of Table 2 under reduced pressure of 210 degreeC and 8 kPa, and obtained crystalline polyester B-2. The physical properties of the resin are shown in Table 2.

Production Example 8
(Production of crystalline polyester B-3)
The polyester raw material monomer, esterification catalyst and radical polymerization inhibitor shown in Table 2 were placed in a 10-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser and a nitrogen inlet tube, and a nitrogen atmosphere The temperature was raised from 180 ° C. to 210 ° C. over 6 hours in a mantle heater. Then, it reacted until it reached the acid value of Table 2 under reduced pressure of 210 degreeC and 8 kPa, and obtained crystalline polyester B-3. The physical properties of the resin are shown in Table 2. In Production Example 3, fumaric acid is added to the reaction system in the late stage of polymerization. However, in Production Example 8, fumaric acid is added to the reaction system in the early stage of polymerization.

Production Example 9
(Production of amorphous polyester D-1 for shell)
The polyester raw material monomer other than dodecenyl succinic anhydride shown in Table 3, esterification catalyst and esterification co-catalyst, 10 liter four-neck equipped with thermometer, stainless steel stirring rod, flow-down condenser and nitrogen inlet tube The flask was put into a flask, heated to 235 ° C. over 2 hours in a mantle heater in a nitrogen atmosphere, reacted at 235 ° C. for 10 hours, and it was confirmed that the reaction rate reached 95% or more. Then, after reacting at 235 ° C. under a reduced pressure of 8 kPa for 1 hour, dodecenyl succinic anhydride and a radical polymerization inhibitor (4-t-butylcatechol) were added as shown in Table 3, and the pressure was increased to 235 ° C. and normal pressure. After reacting for 1 hour, the reaction was carried out at 8 kPa until the acid values shown in Table 3 were reached, and amorphous polyester D-1 was obtained.

Production Example 10
(Production of amorphous polyester D-2 for core)
The raw material monomer of polyester other than fumaric acid, esterification catalyst and esterification co-catalyst shown in Table 3 were added to a 10-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser and a nitrogen inlet tube. Then, after heating up to 235 ° C. over 2 hours in a mantle heater in a nitrogen atmosphere, the reaction was performed at 235 ° C. for 10 hours, and it was confirmed that the reaction rate reached 95% or more. Then, after making it react under reduced pressure of 235 degreeC and 8 kPa for 1 hour, it cooled to 180 degreeC. Then, as shown in Table 3, fumaric acid and a radical polymerization inhibitor (4-t-butylcatechol) were added, and the temperature was raised to 210 ° C. over 2 hours. Then, after reacting at 210 ° C. for 1 hour, the reaction was performed at 8 kPa until the acid values shown in Table 3 were reached, to obtain amorphous polyester D-2.

[Production of aqueous dispersion]
Aqueous dispersion production example 1
(Production of aqueous dispersion A-1)
In a 3 L container equipped with a stirrer, reflux condenser, dropping funnel, thermometer and nitrogen introduction tube, 150 g of crystalline polyester A-1 and 75 g of ethyl acetate were charged and dissolved at 70 ° C. over 2 hours. . A 20% by mass aqueous ammonia solution (pKa: 9.3) was added to the obtained solution so that the degree of neutralization was 100 mol% with respect to the acid value of the resin, and the mixture was stirred for 30 minutes to obtain a mixture. (Step 1). While maintaining at 70 ° C., 675 g of ion-exchanged water was added over 77 minutes while stirring at 280 r / min (peripheral speed 88 m / min), and phase inversion emulsification was performed to obtain a crude dispersion of resin particles ( Step 2). While maintaining the temperature at 70 ° C., ethyl acetate was distilled off under reduced pressure to obtain an aqueous dispersion of resin particles (Step 3).
Thereafter, the aqueous dispersion was cooled to 30 ° C. while stirring at 280 r / min (peripheral speed 88 m / min), and then an anionic surfactant “Emar E27C” (sodium polyoxyethylene lauryl ether sulfate, Kao Corporation). 16.7 g of the product (solid content, 28% by mass) were mixed and completely dissolved (step 4). Thereafter, the solid concentration of the aqueous dispersion was measured, and ion exchange water was added to adjust the solid concentration of the aqueous dispersion to 20% by mass. The volume median particle size of the resin particles in the obtained aqueous dispersion was 187 nm.

Aqueous dispersion production examples 2 to 10
(Production of aqueous dispersions A-2 to D-2)
In aqueous dispersion production example 1, an aqueous dispersion was obtained in the same manner as in Production Example 1, except that the resin used in step 1 was changed to the resins shown in Tables 4 to 6. Tables 4 to 6 show the volume-median particle size and solid content concentration of the resin particles in the obtained aqueous dispersion.

[Production of colorant dispersion]
Aqueous dispersion production example 11
Mixing 50 g of copper phthalocyanine “ECB-301” (manufactured by Dainichi Seika Kogyo Co., Ltd.), 5 g of nonionic surfactant “Emulgen 150” (polyoxyethylene lauryl ether, manufactured by Kao Corporation) and 200 g of ion-exchanged water The mixture was dispersed for 10 minutes using a homogenizer to obtain a colorant dispersion containing colorant particles. The volume median particle size (D ₅₀ ) of the colorant particles was 120 nm, and the solid content concentration was 22% by mass.

[Production of charge control agent dispersion]
Aqueous dispersion production example 12
Mixing 50 g of salicylic acid compound “Bontron E-84” (Orient Chemical Co., Ltd.) as a charge control agent, 5 g of “Emulgen 150” (Kao Co., Ltd.) as a nonionic surfactant and 200 g of ion-exchanged water Then, glass beads were used and dispersed for 10 minutes using a sand grinder to obtain a charge control agent dispersion containing charge control agent particles. The volume median particle size (D ₅₀ ) of the charge control agent particles was 400 nm, and the solid content concentration was 22% by mass.

[Production of release agent dispersion]
Aqueous dispersion production example 13
50 g of paraffin wax (manufactured by Nippon Seiwa Co., Ltd., trade name: “HNP9”, melting point: 85 ° C.), 5 g of cationic surfactant (trade name: “Sanisol B50” manufactured by Kao Corporation) and ion-exchanged water 200 g was heated to 95 ° C., and the paraffin wax was dispersed using a homogenizer, followed by dispersion treatment using a pressure discharge homogenizer to obtain a release agent dispersion containing release agent particles. The volume median particle size (D ₅₀ ) of the release agent particles (paraffin wax) was 450 nm, and the solid content concentration was 22% by mass.

[Manufacture of toner for developing electrostatic image]
Example 1
60 g of the aqueous dispersion A-1, 240 g of the aqueous dispersion D-2, 8 g of the colorant dispersion, 10 g of the release agent dispersion, 2 g of the charge control agent dispersion, and 52 g of deionized water are placed in a 3 L container. Under stirring at 100 r / min (peripheral speed 31 m / min) with an anchor-type stirrer, 150 g of a 0.1 mass% calcium chloride aqueous solution was added dropwise at 20 ° C. over 30 minutes. Then, it heated up to 50 degreeC, stirring. After 3 hours, an aggregate x having a volume median particle size of 4 μm was obtained. Thereafter, 33 g of the aqueous dispersion D-1 was added as a raw material for the shell of the toner and stirred to form an amorphous polyester around the shell aggregate x. Then, a dilute solution obtained by diluting 4.2 g of anionic surfactant “Emar E27C” (manufactured by Kao Corporation, solid content: 28% by mass) with 37 g of deionized water was added as an aggregation terminator. Obtained. Next, the temperature was raised to 80 ° C., and after maintaining at 80 ° C. for 1 hour from the time when the temperature reached 80 ° C., the heating was terminated. As a result, fused particles were formed, and then slowly cooled to 20 ° C., filtered through a 150 mesh (mesh 150 μm) wire mesh, suction filtered, and washed and dried to obtain toner particles. .

(External addition process)
Hydrophobic silica “NAX-50” (manufactured by Nippon Aerosil Co., Ltd., number average particle size 40 nm) 1.0 part by mass, hydrophobic silica “R972” (Nippon Aerosil Co., Ltd.) with respect to 100 parts by mass of the toner particles. Manufactured, number average particle size 16 nm) 0.6 parts by mass, titanium oxide “JMT-150IB” (manufactured by Teica Co., Ltd., number average particle size 15 nm) 0.5 parts by mass, ST, A0 equipped with a stirring blade 10 L A Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) was added and stirred at 3000 rpm for 2 minutes to obtain a toner. Table 7 shows the evaluation results of the obtained toner.

Examples 2 to 6 and Comparative Examples 1 and 2
A toner was obtained in the same manner as in Example 1 except that the aqueous dispersion used was changed to the type and amount of the aqueous dispersion shown in Tables 7 and 8. Tables 7 and 8 show the evaluation results of the obtained toner.

  From Tables 7 and 8, it can be seen that the electrostatic charge image developing toners of the examples are all superior in low-temperature fixability, heat-resistant storage stability and chargeability as compared with the comparative electrostatic charge image developing toners.

  The toner for developing an electrostatic image obtained by the production method of the present invention is excellent in low-temperature fixing property, heat-resistant storage property and charging property, and therefore can be suitably used as a toner used in electrophotography. According to the method of the present invention, a toner having such characteristics can be produced efficiently.

Claims (7)

Resin particles containing a crystalline polyester (A) in which the proportion of carboxy groups derived from dicarboxylic acid monomers having a second dissociation constant (pKa2) of 5 or less among carboxy groups at the end of the polyester chain is 70 mol% or more And a step I of obtaining an aggregate X containing the resin particles containing the amorphous polyester (B) in an aqueous medium, and a step II of fusing the aggregate X. A toner manufacturing method comprising :
The dicarboxylic acid monomer having the second dissociation constant (pKa2) of 5 or less is one or more selected from fumaric acid and isophthalic acid,
70 mol% or more of the carboxylic acid monomer forming the inside of the polyester chain of the crystalline polyester (A) is a saturated aliphatic dicarboxylic acid,
A method for producing a toner for developing an electrostatic charge image, wherein the saturated aliphatic dicarboxylic acid is one or more selected from succinic acid, adipic acid, sebacic acid and dodecanedioic acid . Of the carboxy groups at the end of the polyester chain of the amorphous polyester resin (B), the proportion of carboxy groups resulting from the dicarboxylic acid monomer having a second dissociation constant (pKa2) of 5 or less is 70 mol% or more. The method for producing a toner for developing an electrostatic charge image according to claim 1 . In Step I, the aqueous dispersion (a) obtained by dispersing the resin particles containing the crystalline polyester (A) in the aqueous medium and the resin particles containing the amorphous polyester (B) are dispersed in the aqueous medium. it is to use an aqueous dispersion (b) comprising by claim 1 or 2 method for producing a toner according to. The production of the electrostatic image developing toner according to claim 3 , wherein the aqueous dispersion (a) is obtained by a method comprising a step of adding an aqueous medium to the crystalline polyester (A) and phase inversion emulsification. Method. A step in which the aqueous dispersion (a) is a mixture of the crystalline polyester (A) and an organic solvent to obtain a mixture (step 1), an aqueous medium is added to the mixture, phase inversion emulsification is carried out, and a crude dispersion of resin particles The method according to claim 3 or 4 , which is obtained by a method comprising a step (Step 2) of obtaining an aqueous dispersion of resin particles by distilling off an organic solvent from the crude dispersion (Step 3). A method for producing the toner for developing an electrostatic image according to claim 1. Crystalline polyester (A) is one obtained through a manufacturing process comprising the step of reacting a dicarboxylic acid monomer precursor crystalline polyester and the second dissociation constant (pKa2) is 5 or less, claim 1-5 A method for producing a toner for developing an electrostatic image according to any one of the above. Step I is a step Ia in which the resin particles containing the crystalline polyester (A) and the resin particles containing the amorphous polyester (B) are aggregated in the aqueous medium to obtain the core aggregate x. And resin particles containing the amorphous polyester for shell (C) are further mixed in the aqueous medium to aggregate the resin particles containing the core aggregate x and the amorphous polyester (C). , and a step Ib to obtain said agglomerate X, claim 1-6 or method of manufacturing a toner according to the.