JP7062919B2 - Toner for static charge image development - Google Patents

Description

The present invention relates to a toner for developing an electrostatic charge image, and more particularly to a toner for developing an electrostatic charge image, which is excellent in low-temperature fixing property and heat-resistant storage property and also has toner fluidity.

In recent years, in an electrophotographic image forming apparatus, a toner for static charge image development (hereinafter referred to as a toner for static charge image development) which is thermally fixed at a lower temperature in order to further save energy for the purpose of increasing the printing speed and reducing the environmental load. , Simply referred to as "toner") is required. For such toners, it is necessary to lower the melting temperature and melting viscosity of the binder resin, and a toner having improved low-temperature fixability by adding a crystalline resin such as a crystalline polyester resin has been proposed. ing.
However, in the case of a toner containing a crystalline resin, if the toner is heated above the melting point of the crystalline resin during the production of the toner, the crystalline resin will be compatible with the amorphous resin even during the production, so that the heat-resistant storage property There was a problem that it got worse.

As a means for improving the heat-resistant storage property of the toner having such a structure, for example, Patent Document 1 states that two types of crystalline polyester resins have different domains and are contained in the crystalline polyester resin and the vinyl resin. It is reported that the trade-off between low-temperature fixability and heat-resistant storage can be resolved because incompatibility can be controlled.
However, due to the variation in the particle size distribution of the crystalline polyester resin, the heat-resistant storage property may change due to the disruption of the compatible and incompatible relationship with other resins, and the heat-resistant storage property is surely improved. There is a problem that it cannot be secured.

In Patent Document 2, the resin A and the resin B melt when the paper such as thin paper double-sided printing tends to be fixed at a high temperature by containing two kinds of crystalline polyester resins. At this time, the SP values are close to each other. If so, it has been reported that they are compatible with each other and behave as an intermediate crystalline polyester resin between the two resins, ensuring low-temperature fixing and heat-resistant storage.
However, since it is not sufficient to suppress the surface exposure of the crystalline resin, aggregation and fusion occur between the toner particles due to environmental changes, so that low temperature fixing and heat storage stability cannot be ensured at the same time. Was left.

In Patent Document 3, as a means for dispersing the crystalline polyester in the styrene / acrylic resin, the SP value of the styrene / acrylic resin and the dispersant is set to 0.10 or less. At room temperature, the styrene / acrylic resin and the modified polyester resin have a phase-separated structure to maintain the softening point and obtain high heat-resistant storage properties. Further, by using the dispersant, the modified polyester resin is highly dispersed in the styrene / acrylic resin, and the fixing unevenness is suppressed, so that uniform in-plane gloss can be obtained.
However, since it is not sufficient to suppress the surface exposure of the crystalline resin, aggregation and fusion occur between the toner particles due to environmental changes, so that it is not possible to secure both low temperature fixability and heat storage property. The problem was left.

JP-A-2015-11054 Japanese Unexamined Patent Publication No. 2015-114482 Japanese Unexamined Patent Publication No. 2016-224139

The present invention has been made in view of the above problems and situations, and the solution thereof is to provide a toner for static charge image development which is excellent in low temperature fixing property and heat storage property and also has toner fluidity. be.

In the process of investigating the cause of the above problem in order to solve the above-mentioned problems, the present inventor has determined the carbon number of the polyvalent alcohol component and the carbon number of the polyvalent carboxylic acid component of the two types of crystalline polyester resins. We have found that it is possible to provide a toner for static charge image development which is excellent in low temperature fixing property and heat-resistant storage property and also has toner fluidity by controlling so as to satisfy a specific relationship, and has arrived at the present invention.
That is, the above-mentioned problem according to the present invention is solved by the following means.
1. 1. A toner for developing an electrostatic charge image containing at least toner matrix particles,
The toner matrix particles contain an amorphous resin, a mold release agent, a crystalline resin 1, and a crystalline resin 2.
The crystalline resin 1 and the crystalline resin 2 are crystalline polyester resins containing a polyhydric alcohol and a polyvalent carboxylic acid as monomer components.
The carbon number of the polyvalent alcohol component of the crystalline resin 1 (C1 (alcohol)), the carbon number of the polyvalent alcohol component of the crystalline resin 2 (C2 (alcohol)), and the polyvalent value of the crystalline resin 1. The carbon number of the carboxylic acid component (C1 (acid)) and the carbon number of the polyvalent carboxylic acid component of the crystalline resin 2 (C2 (acid)) satisfy the relationship of the following formulas (1) to (4). However, the carbon number of the polyvalent carboxylic acid component is a carbon number that does not contain carbon of a carboxy group, and is a toner for static charge image development.
C1 (acid)> C1 (alcohol) ... Equation (1)
C2 (acid)> C2 (alcohol) ... Equation (2)
C1 (alcohol) ≠ C2 (alcohol) ... Equation (3)
12 ≤ C1 (acid) = C2 (acid) ≤ 14 ... Equation (4)

2. 2. Item 2. The static charge according to the first item, wherein the content of at least the crystalline resin 1 and the crystalline resin 2 is in the range of 2.0 to 30% by mass with respect to the amorphous resin. Toner for image development.

3. 3. The carbon number (C1 (alcohol)) of the polyhydric alcohol component of the crystalline resin 1 and the carbon number (C2 (alcohol)) of the polyhydric alcohol component of the crystalline resin 2 have the relationship of the following formula (5). The toner for static charge image development according to the first or second item, which is characterized by satisfying.
| C1 (alcohol) -C2 (alcohol) | ≧ 2 ... Equation (5)

4 . At least the number of carbon atoms (C1 (alcohol)) of the crystalline resin 1 and the number of carbon atoms (C2 (alcohol)) of the polyhydric alcohol component of the crystalline resin 2 satisfy the following formula (8), and the mass ratio thereof. The static charge image according to any one of the items 1 to 3 , wherein the value of (crystalline resin 1 / crystalline resin 2) is in the range of 60/40 to 1/99. Development toner.
C1 (alcohol)> C2 (alcohol) ... Equation (8)

5 . The toner for static charge image development according to any one of items 1 to 4 , wherein the amorphous resin contains a styrene / acrylic resin.

By the above means of the present invention, it is possible to provide a toner for static charge image development which is excellent in low temperature fixing property and heat-resistant storage property and also has toner fluidity.
Although the mechanism of expression or mechanism of action of the effect of the present invention has not been clarified, it is inferred as follows.
In the crystalline resins 1 and 2, by increasing the carbon number of the carboxylic acid component to be larger than the carbon number of the alcohol component (formulas (1) and (2) above), the compatibility with the amorphous resin is increased. It is possible to prevent the crystalline resin from being exposed on the surface of the toner matrix particles, and it has excellent low-temperature fixability. That is, by increasing the number of carbon atoms of the carboxylic acid component, the SP value becomes small, and it becomes easy to be compatible with the amorphous resin at the time of fixing.
Further, by using two kinds of crystalline resins 1 and 2 (the above formulas (3) and (4)), the compatibility of one of the crystalline resins 1 with the mold release agent is enhanced, and the high temperature of the mold release agent is increased. Bleed-out during storage can be suppressed, and the compatibility of the other crystalline resin 2 with the amorphous resin can be enhanced.
Further, by making the carbon atoms of the carboxylic acid components of the crystalline resins 1 and 2 the same (the above formula (4)), the melting points of the two types of crystalline resins having the respective functions as described above are made uniform. And the compatibility between the crystalline resins 1 and 2 can be enhanced. Further, when the crystallinity is the same, the crystalline resins 1 and 2 in the toner can easily take the same domain.
As described above, by satisfying the above formulas (1) to (4), that is, by controlling the SP value of each composition, the effect of the composition contained in the toner can be maximized. Specifically, since the crystalline resin has high compatibility with the amorphous resin and further has high compatibility with the release agent, a toner having excellent low-temperature fixability, heat-resistant storage property, and toner fluidity can be obtained. Can be provided.

The static charge image developing toner of the present invention is a static charge image developing toner containing at least toner matrix particles, and the toner matrix particles are an amorphous resin, a mold release agent, and a crystalline resin 1. The crystalline resin 1 and the crystalline resin 2 are crystalline polyester resins containing polyhydric alcohol and polyvalent carboxylic acid as monomer components, and the crystalline resin 1 is polyvalent. The number of carbon atoms of the alcohol component (C1 (alcohol)), the number of carbon atoms of the polyvalent alcohol component of the crystalline resin 2 (C2 (alcohol)), and the number of carbon atoms of the polyvalent carboxylic acid component of the crystalline resin 1 (C1). (Acid)) and the number of carbon atoms (C2 (acid)) of the polyvalent carboxylic acid component of the crystalline resin 2 satisfy the relationship of the above formulas (1) to (4).
This feature is a technical feature common to or corresponding to the invention according to the present embodiment.

In an embodiment of the present invention, the content of the crystalline resin 1 and the crystalline resin 2 is at least in the range of 2.0 to 30% by mass with respect to the amorphous resin, which is low-temperature fixing. It is preferable in that the property is good.

Further, the carbon number of the polyhydric alcohol component of the crystalline resin 1 (C1 (alcohol)) and the carbon number of the polyhydric alcohol component of the crystalline resin 2 (C2 (alcohol)) are represented by the above formula (5). Satisfying the relationship is preferable in terms of low-temperature fixability, heat-resistant storage property, and toner fluidity, because the effect of containing two types of crystalline resin is enhanced.

Further, at least the number of carbon atoms of the crystalline resin 1 (C1 (alcohol)) and the number of carbon atoms of the polyhydric alcohol component of the crystalline resin 2 (C2 (alcohol)) satisfy the formula (8) and the mass thereof. When the ratio value (crystalline resin 1 / crystalline resin 2) is in the range of 60/40 to 1/99, the two types of crystalline resin are contained, and the toner fluidity is not impaired without impairing the toner performance. It is preferable in that it can secure.

Further, it is preferable that the amorphous resin contains a styrene / acrylic resin in that toner can be produced at low cost.

Hereinafter, the present invention, its constituent elements, and modes and embodiments for carrying out the present invention will be described. In addition, in this application, "-" is used in the sense that the numerical values described before and after it are included as the lower limit value and the upper limit value.

[Toner for developing static charge image]
The toner of the present invention is a toner for static charge image development containing at least toner matrix particles, and the toner matrix particles are an amorphous resin, a mold release agent, a crystalline resin 1, and a crystalline resin 2. The crystalline resin 1 and the crystalline resin 2 contain a non-crystalline resin, a mold release agent, a crystalline resin 1, and a crystalline resin 2, and the crystalline resin 1 and the crystalline resin 2 contain a polyhydric alcohol and a polyvalent carboxylic. It is a crystalline polyester resin containing an acid as a monomer component, and has the carbon number of the polyvalent alcohol component of the crystalline resin 1 (C1 (alcohol)) and the carbon number of the polyvalent alcohol component of the crystalline resin 2 (C2 (C2). alcohol)), the number of carbon atoms (C1 (acid)) of the polyvalent carboxylic acid component of the crystalline resin 1, and the number of carbon atoms (C2 (acid)) of the polyvalent carboxylic acid component of the crystalline resin 2. The relationship of the following formulas (1) to (4) is satisfied, and the carbon number of the polyvalent carboxylic acid component is characterized by the number of carbons containing no carbon of the carboxy group .
C1 (acid)> C1 (alcohol) ... Equation (1)
C2 (acid)> C2 (alcohol) ... Equation (2)
C1 (alcohol) ≠ C2 (alcohol) ... Equation (3)
12 ≤ C1 (acid) = C2 (acid) ≤ 14 ... Equation (4)

In the present invention, the carbon number of the polyvalent carboxylic acid component means the carbon number of the carboxy group not including the carbon, and the carbon number of the polyhydric alcohol component means the carbon number connected from the hydroxy group.

<Toner matrix particles>
The toner matrix particles according to the present invention contain an amorphous resin, a mold release agent, a crystalline resin 1, and a crystalline resin 2.
In addition, the toner matrix particles according to the present invention may contain other constituent components such as a colorant, a mold release agent (wax), and a charge control agent, if necessary.

In the present invention, toner particles obtained by adding an external additive to toner matrix particles are referred to as toner particles, and an aggregate of toner particles is referred to as toner. Generally, the toner matrix particles can be used as they are as toner particles, but in the present invention, the toner matrix particles to which an external additive is added are used as the toner particles.

<Crystallinic resin 1 and crystalline resin 2>
The crystalline resin 1 and the crystalline resin 2 according to the present invention are crystalline polyester resins containing polyhydric alcohol and polyvalent carboxylic acid as monomer components.
Here, the reason why the two types of crystalline resins 1 and 2 are used is to achieve both manufacturability and performance as a toner.
By mixing the crystalline resins 1 and 2 with the amorphous resin described in detail below, the crystalline resin 2 is compatible with the amorphous resin at the time of heat fixing. As a result, the toner can be fixed at a low temperature, and energy can be saved.

In the present invention, the crystalline resin refers to a resin having a clear endothermic peak instead of a stepped endothermic change in differential scanning calorimetry (DSC). A clear endothermic peak specifically means a peak in which the half width of the endothermic peak is within 15 ° C. when measured at a temperature rise rate of 10 ° C./min in differential scanning calorimetry (DSC). do.

The crystalline resins 1 and 2 are not particularly limited as long as they have the above-mentioned characteristics and satisfy the relations of the above formulas (1) to (4), and conventionally known crystalline resins in the present technical field can be used. Can be used.
Specific examples thereof include crystalline polyester resin, crystalline polyurethane resin, crystalline polyurea resin, crystalline polyamide resin, and crystalline polyether resin. The crystalline resin can be used alone or in combination of two or more.
Above all, the crystalline resin according to the present invention is preferably a crystalline polyester resin. Here, the "crystalline polyester resin" is obtained by a polycondensation reaction between a divalent or higher carboxylic acid (polyvalent carboxylic acid) and its derivative and a dihydric or higher alcohol (polyhydric alcohol) and its derivative. Among known polyester resins, it is a resin that satisfies the above heat absorption characteristics.

The melting point of the crystalline polyester resin is not particularly limited, but is preferably in the range of 55 to 90 ° C. When the melting point of the crystalline polyester resin is in the above range, sufficient low temperature fixability can be obtained. From this point of view, it is more preferably in the range of 60 to 85 ° C. The melting point of the crystalline polyester resin can be controlled by the resin composition.
Further, in the present specification, the melting point of the resin can be measured by the method described in Examples described later.

Further, in the present invention, the low temperature fixability is that the content of at least the crystalline resin 1 and the crystalline resin 2 is in the range of 2.0 to 30% by mass with respect to the amorphous resin. It is preferable in terms of good results, and more preferably about 20% by mass.

(About equation (1) and equation (2))
C1 (acid)> C1 (alcohol) ... Equation (1)
C2 (acid)> C2 (alcohol) ... Equation (2)
The two types of crystalline resins 1 and 2 are characterized in that they satisfy the relationship of the above formulas (1) and (2). As a result, the number of carbon atoms of the carboxylic acid component is larger than the number of carbon atoms of the alcohol component. As the number of carbon atoms of the carboxylic acid component increases, the SP value becomes smaller, and it becomes easier to be compatible with the amorphous resin at the time of fixing. As a result, the low temperature fixing property becomes good.

(About equation (3) and equation (4))
C1 (alcohol) ≠ C2 (alcohol) ... Equation (3)
12 ≤ C1 (acid) = C2 (acid) ≤ 14 ... Equation (4)
The two types of crystalline resins 1 and 2 are characterized in that they satisfy the relationships of the above formulas (3) and (4). As a result, one of the crystalline resins 1 can enhance the compatibility with the release agent and suppress bleed-out during high temperature storage of the release agent, and the other crystalline resin 2 can be used with the amorphous resin. Compatibility can be enhanced.
Further, by making the carbon atoms of the carboxylic acid components of the crystalline resins 1 and 2 the same, the melting points of the two types of crystalline resins 1 and 2 can be made uniform, and the compatibility between the crystalline resins 1 and 2 can be improved. Can be enhanced. Further, when the crystallinity is the same, the crystalline resins 1 and 2 in the toner can easily take the same domain.

(About formula (5))
The carbon number (C1 (alcohol)) of the polyhydric alcohol component of the crystalline resin 1 and the carbon number (C2 (alcohol)) of the polyhydric alcohol component of the crystalline resin 2 have the relationship of the following formula (5). Satisfaction is preferable in terms of low-temperature fixability, heat-resistant storage property, and toner fluidity, because the effect of containing two types of crystalline resin is enhanced.
| C1 (alcohol) -C2 (alcohol) | ≧ 2 ... Equation (5)
(About equation (6) and equation (7))
The carbon number (C1 (acid)) of the polyvalent carboxylic acid component of the crystalline resin 1 and the carbon number (C2 (acid)) of the polyvalent carboxylic acid component of the crystalline resin 2 are the following formula (6) and. Satisfying the relationship (7) is preferable in terms of increasing compatibility with the release agent and suppressing bleed-out of the release agent during high temperature storage of the toner.
C1 (acid) ≧ 10 ... Equation (6)
C2 (acid) ≧ 10 ... Equation (7)

(About formula (8))
At least the number of carbon atoms of the crystalline resin 1 (C1 (alcohol)) and the number of carbon atoms of the polyhydric alcohol component of the crystalline resin 2 (C2 (alcohol)) satisfy the formula (8) and have a mass ratio thereof. The value (crystalline resin 1 / crystalline resin 2) is in the range of 60/40 to 1/99, which contains two types of crystalline resin and ensures toner fluidity without impairing toner performance. It is preferable in that it can be used.
C1 (alcohol)> C2 (alcohol) ... Equation (8)
Further, the value of the mass ratio is more preferably in the range of 30/70 to 1/99.

(Polyvalent carboxylic acid component)
Examples of the polyvalent carboxylic acid component constituting the crystalline polyester resins 1 and 2 according to the present invention include oxalic acid (ethanedioic acid), malonic acid (propanedioic acid), succinic acid (butanedioic acid), and glutaric acid. (Pentanedioic acid), adipic acid (hexanedioic acid), pimelic acid (heptanedioic acid), suberic acid (octanedioic acid , 1,6-hexanedicarboxylic acid: COOH-C _6H 12 _- COOH ), azelaic acid ( Nonanedioic acid), sebacic acid (decanedioic acid , 1,8-octanedicarboxylic acid: COOH-C ₈ H ₁₆ - COOH ), 1,9-nonandicarboxylic acid (undecanedioic acid : COOH-C ₉ H ₁₈ - COOH ) ), 1,10-Decandicarboxylic acid (dodecanedioic acid : COOH-C 10H ₂₀ - COOH ), 1,11-undecanedicarboxylic acid (tridecanedioic acid : COOH-C ₁₁ H ₂₂ - COOH ), _1,12- Dodecanedicarboxylic acid (tetradecanedioic acid : COOH-C ₁₂ H ₂₄ - COOH ), 1,13-tridecanedicarboxylic acid (pentadecanedioic acid : COOH-C ₁₃ H ₂₆ - COOH ), 1,14-tetradecanedicarboxylic acid (hexadecane) Diacid: COOH-C ₁₄ H ₂₈ - COOH ) and the like can be used. Moreover, you may use these lower alkyl esters and acid anhydrides. The polyvalent carboxylic acid may be used alone or in combination of two or more.
In the names of the polyvalent carboxylic acid components, aliases and structural formulas are shown in parentheses.

(Multivalent alcohol component)
Examples of the polyhydric alcohol component constituting the crystalline polyester resins 1 and 2 according to the present invention include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, and 1,5-pentane. Diol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, neopentyl glycol, Polyhydric diols such as 1,4-butenediol; trihydric or higher polyhydric alcohols such as glycerin, pentaerythritol, trimethylolpropane, and sorbitol; and the like. Moreover, you may use these derivatives. The polyhydric alcohol may be used alone or in combination of two or more.

The number average molecular weight (Mn) of the crystalline polyester resin is not particularly limited, but is preferably in the range of 1500 to 25000, and more preferably in the range of 3000 to 20000. Within such a range, the low temperature fixability can be further improved. The number average molecular weight (Mn) can be measured by gel permeation chromatography (GPC), and specifically, can be measured by the method described in Examples.

The method for producing the crystalline polyester resin is not particularly limited, and it can be produced by polycondensing (esterifying) the polyhydric alcohol and the polyvalent carboxylic acid using a known esterification catalyst.
As catalysts that can be used in the production of crystalline polyester resins, alkali metal compounds such as sodium and lithium; compounds containing Group 2 elements such as magnesium and calcium; aluminum, zinc, manganese, antimony, titanium, tin, Examples thereof include metal compounds such as zirconium and germanium; subphosphate compounds; phosphate compounds; and amine compounds. Considering availability, dibutyltin oxide, tin octylate, tin dioctylate, salts thereof, tetranormal butyl titanate (tetrabutyl orthotitanium), tetraisopropyl titanate (titanium tetraisopropoxide), tetramethyl titanate, etc. It is preferable to use. These may be used alone or in combination of two or more.
The temperature of polycondensation (esterification) is not particularly limited, but is preferably in the range of 150 to 250 ° C. The polycondensation (esterification) time is not particularly limited, but is preferably in the range of 0.5 to 15 hours. During the polycondensation, the pressure inside the reaction system may be reduced as needed.

The toner of the present invention contains an amorphous resin in addition to the above-mentioned crystalline polyester resins 1 and 2 as a binder resin.
The toner of the present invention has a low temperature fixability when the content of at least the crystalline resin 1 and the crystalline resin 2 is in the range of 2.0 to 30% by mass with respect to the amorphous resin. It is preferable in that it becomes good. More preferably, it is in the range of 5 to 25% by mass.

The total content of the crystalline polyester resins 1 and 2 in the toner of the present invention is preferably in the range of 1 to 30% by mass, respectively, in the range of 3 to 20% by mass with respect to the entire binder resin. Is more preferable, and it is particularly preferable that the content is in the range of 6 to 17% by mass.
When the total content of the crystalline polyester resins 1 and 2 is 1% by mass or more, they are appropriately plasticized by compatibility with the amorphous resin, and the low-temperature fixability is easily improved. On the other hand, when the content of the crystalline polyester resins 1 and 2 is 30% by mass or less, the crystalline polyester resins 1 and 2 are less likely to be exposed on the surface of the toner matrix particles in the toner, so that the chargeability is further improved. Even in a high temperature and high humidity environment, uneven image density is suppressed and the image density is also improved.

Further, from the viewpoint of improving the low temperature fixability and suppressing the environment dependence of the image density unevenness, the contents of the crystalline polyester resin in the toner of the present invention are crystalline polyester resins 1 and 2, respectively, and amorphous. It is preferably in the range of 1 to 30% by mass, more preferably in the range of 3 to 20% by mass, and 6 to 15% by mass with respect to the total mass of the resin and the mold release agent. It is particularly preferable that it is within the range. Within such a range, the low temperature fixing property is excellent and the density of the formed image is also improved.
The structure of the constituent components (constituent units) of the crystalline polyester resins 1 and 2 and the content (ratio) of each constituent component (each constituent unit) are, for example, NMR measurement and methylation reaction Py-GC / MS measurement. Can be specified by.

<Amorphous resin>
The amorphous resin is preferably the main component of the binder resin contained in the toner.
By containing the amorphous resin as the main component of the binder resin, the amorphous resin is likely to be present on the surface of the toner matrix particles. As a result, the chargeability of the toner matrix particles can be improved due to the high electrical resistance of the amorphous resin.
Here, the "main component" means that the resin has the highest content ratio among the binder resins. The amorphous resin is preferably in the range of 50% by mass or more, more preferably in the range of 70 to 99% by mass, and in the range of 80 to 97% by mass with respect to the entire binder resin. Is even more preferable, and particularly preferably in the range of 83 to 94% by mass.
The content of the amorphous resin is in the range of 65 to 95% by mass with respect to the total mass of the crystalline polyester resins 1 and 2, the amorphous resin, and the release agent. It is more preferably in the range of 75 to 90% by mass, and particularly preferably in the range of 80 to 88% by mass. Within such a range, the low temperature fixing property is excellent and the density of the formed image is also improved.

In the present invention, the amorphous resin is a resin that does not have a melting point and has a relatively high glass transition temperature (Tg) when differential scanning calorimetry (DSC) is performed. At this time, the glass transition temperature (Tg) is preferably in the range of 30 to 80 ° C, and particularly preferably in the range of 40 to 65 ° C.
The glass transition temperature (Tg) can be measured by a differential calorimetry device (DSC), and specifically, it is measured by the method described in Examples. Those skilled in the art can control the glass transition temperature by the composition of the resin.
As the amorphous resin, a conventionally known amorphous resin in the present technical field can be used, but among them, an amorphous polyester resin or a vinyl resin is preferable, and these resins may be mixed and used. In particular, the amorphous resin preferably contains a vinyl resin from the viewpoint of excellent environmental stability of the amount of charge.

(Vinyl resin)
The vinyl resin is a resin obtained by polymerization using at least a vinyl monomer. Specific examples of the vinyl resin include acrylic resin and styrene / acrylic copolymer resin (styrene / acrylic resin).
Among them, as the vinyl resin, a styrene / acrylic copolymer resin formed by using a styrene monomer and a (meth) acrylic acid ester monomer is preferable. That is, the amorphous resin according to the present invention preferably contains a styrene / acrylic resin.
The styrene / acrylic copolymer resin is particularly suitable as the amorphous resin according to the present invention because it is excellent in environmental stability of the amount of charge. The vinyl resin may be used alone or in combination of two or more.
As the vinyl monomer forming the vinyl resin, one or more selected from the following can be used.

(1) Styrene Styrene Styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-tert- Butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene and derivatives thereof.

(2) (Meta) Acrylic Acid Ester Monomer: Methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate (n-butyl (meth) acrylate), isopropyl (meth) acrylate , (Meta) isobutyl acrylate, (meth) t-butyl acrylate, (meth) n-octyl acrylate, (meth) 2-ethylhexyl acrylate, (meth) stearyl acrylate, (meth) lauryl acrylate, ( Phenyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate and derivatives thereof.

(3) Vinyl esters Vinyl propionate, vinyl acetate, vinyl benzoate, etc.

(4) Vinyl ethers Vinyl methyl ether, vinyl ethyl ether, etc.

(5) Vinyl ketones Vinyl methyl ketone, vinyl ethyl ketone, vinyl hexyl ketone, etc.

(6) N-vinyl compounds N-vinylcarbazole, N-vinylindole, N-vinylpyrrolidone and the like.

(7) Others Vinyl compounds such as vinylnaphthalene and vinylpyridine, acrylic acid such as acrylonitrile, methacrylicnitrile, and acrylamide, or methacrylic acid derivatives.

Further, as the vinyl monomer, for example, it is preferable to use a monomer having an ionic dissociation group such as a carboxy group, a sulfonic acid group, and a phosphoric acid group. Specifically, there are the following.
Examples of the monomer having a carboxy group include acrylic acid, methacrylic acid, maleic acid, itaconic acid, silicic acid, fumaric acid, maleic acid monoalkyl ester, and itaconic acid monoalkyl ester.
Examples of the monomer having a sulfonic acid group include styrene sulfonic acid, allylsulfosuccinic acid, 2-acrylamide-2-methylpropanesulfonic acid and the like.
Further, examples of the monomer having a phosphoric acid group include acid phosphooxyethyl methacrylate.

Further, polyfunctional vinyls may be used as the vinyl monomer, and a vinyl resin having a crosslinked structure may be used.
Examples of polyfunctional vinyls include divinylbenzene, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, and neopentyl glycol. Examples include diacrylate.

The method for producing the vinyl resin is not particularly limited, and bulk polymerization or solution is used using any polymerization initiator such as peroxide, persulfate, persulfide, and azo compound usually used for the polymerization of the above-mentioned monomers. Examples thereof include a method of polymerizing by a known polymerization method such as polymerization, emulsion polymerization method, miniemulsion method, and dispersion polymerization method.
Further, a commonly used chain transfer agent can be used for the purpose of adjusting the molecular weight. The chain transfer agent is not particularly limited, and examples thereof include alkyl mercaptans and mercapto fatty acid esters.
The molecular weight measured by gel permeation chromatography (GPC) of the vinyl resin is preferably in the range of 10,000 to 100,000 in terms of weight average molecular weight (Mw).
The amorphous resin according to the present invention preferably contains a vinyl resin, and more preferably contains a styrene / acrylic resin. Compared with the amorphous polyester resin, the vinyl resin (particularly styrene / acrylic resin) has few highly polar functional groups and low hygroscopicity, and therefore has good transferability in a high temperature and high humidity environment. Therefore, it is easy to reduce the environment dependence of image density unevenness. In addition, good image density can be obtained without depending on the environment.
The content of the styrene / acrylic resin in the amorphous resin is not particularly limited. As described above, from the viewpoint of reducing the environmental dependence of image density unevenness, the content of the styrene / acrylic resin is preferably 50% by mass or more, preferably 80% by mass, based on the total amount of the amorphous resin. % Or more is more preferable, 90% by mass or more is particularly preferable, and 100% by mass is particularly preferable.

<Release agent>
The release agent according to the present invention is not particularly limited, and various known waxes can be used. For example, a polyolefin wax such as polyethylene wax and polypropylene wax, and a branched chain such as microcrystallin wax can be used. Long-chain hydrocarbon waxes such as hydrocarbon waxes, paraffin waxes and sazole waxes, dialkylketone waxes such as distearyl ketones, carnauba waxes, montan waxes, behenyl behenate, trimethylolpropane tribehenate, pentaerythritol tetra Ester waxes such as behenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18-octadecandiol distearate, tristearyl trimellitic acid, distealyl maleate, ethylenediamine behenylamide, trimerit Examples thereof include amide waxes such as acid tristearyl amide.
Above all, in the toner of the present invention, it is preferable to use highly hydrophobic hydrocarbon waxes as the mold release agent in order to facilitate the presence of crystalline polyester resin inside the toner matrix particles and improve the chargeability. ..

The content of the release agent is preferably in the range of 2 to 20% by mass, more preferably in the range of 3 to 18% by mass, and 5 to 15% by mass with respect to the total amount of the binder resin. It is particularly preferable that it is within the range.
The content of the release agent is preferably in the range of 1 to 15% by mass with respect to the total mass of the crystalline polyester resins 1 and 2, the amorphous resin, and the release agent. It is more preferably in the range of 4 to 13% by mass, and particularly preferably in the range of 5 to 10% by mass. Within such a range, the low temperature fixing property is excellent and the density of the formed image is also improved.
Further, the melting point of the mold release agent is preferably in the range of 50 to 95 ° C. from the viewpoint of low temperature fixability and mold release property of the toner in the electrophotographic method.

<Colorant>
When the toner of the present invention is a black toner, a yellow toner, a magenta toner or a cyan toner, it contains a black colorant, a yellow colorant, a magenta colorant or a cyan colorant shown below, respectively.

(Black colorant)
The colorant used for the black toner includes carbon black.
As the carbon black, channel black, furnace black, acetylene black, thermal black, lamp black and the like are used.
Further, the black toner may further contain a magnetic substance, a dye, other pigments and the like in addition to carbon black. As the magnetic material, a ferromagnetic metal such as iron, nickel, or cobalt, an alloy containing these metals, a ferrite, or a compound of a ferromagnetic metal such as magnetite can be used. Further, as other pigments, titanium black, aniline black and the like can be used.

(Yellow colorant)
The colorant for orange or yellow used for the yellow toner is not particularly limited. For example, as an organic pigment, C.I. I. Pigment Orange 31, C.I. I. Pigment Orange 43, C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 74, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 94, C.I. I. Pigment Yellow 138, C.I. I. Pigment Yellow 155, C.I. I. Pigment Yellow 180, C.I. I. Pigment Yellow 185 and the like.
Further, as the dye, for example, C.I. I. Solvent Yellow 19, C.I. I. Solvent Yellow 44, C.I. I. Solvent Yellow 77, C.I. I. Solvent Yellow 79, C.I. I. Solvent Yellow 81, C.I. I. Solvent Yellow 82, C.I. I. Solvent Yellow 93, C.I. I. Solvent Yellow 98, C.I. I. Solvent Yellow 103, C.I. I. Solvent Yellow 104, C.I. I. Solvent Yellow 112, C.I. I. Solvent Yellow 162 and the like can be mentioned. These colorants may be used alone or in combination of two or more.

(Magenta colorant)
The colorant for magenta or red used for magenta toner is not particularly limited. For example, as an organic pigment, C.I. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I. Pigment Red 6, C.I. I. Pigment Red 7, C.I. I. Pigment Red 15, C.I. I. Pigment Red 16, C.I. I. Pigment Red 48; 1, C.I. I. Pigment Red 53; 1, C.I. I. Pigment Red 57; 1, Pigment Red 81; 4, C.I. I. Pigment Red 122, C.I. I. Pigment Red 123, C.I. I. Pigment Red 139, C.I. I. Pigment Red 144, C.I. I. Pigment Red 149, C.I. I. Pigment Red 150, C.I. I. Pigment Red 166, C.I. I. Pigment Red 177, C.I. I. Pigment Red 178, Pigment Red 184, C.I. I. Pigment Red 222, C.I. I. Pigment Red 238, C.I. I. Pigment Red 269 and the like.
Further, as the dye, for example, C.I. I. Solvent Red 1, Solvent Red 11, C.I. I. Solvent Red 49, C.I. I. Solvent Red 52, C.I. I. Solvent Red 58, C.I. I. Solvent Red 68, C.I. I. Solvent Red 111, C.I. I. Examples include Solvent Red 122 and the like. These colorants may be used alone or in combination of two or more.

(Cyanide colorant)
The green or cyan colorant used for cyan toner is not particularly limited. For example, as an organic pigment, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 15: 3, C.I. I. Pigment Blue 15: 4, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 60, C.I. I. Pigment Blue 62, C.I. I. Pigment Blue 66, C.I. I. Pigment Blue 76, C.I. I. Pigment Green 7 and the like.
Further, as the dye, for example, C.I. I. Solvent Blue 25, C.I. I. Solvent Blue 36, C.I. I. Solvent Blue 69, C.I. I. Solvent Blue 70, C.I. I. Solvent Blue 93, C.I. I. Examples include Solvent Blue 95 and the like. These colorants may be used alone or in combination of two or more.

(Contents of colorant)
The content of each colorant is preferably in the range of 1 to 30 parts by mass with respect to 100 parts by mass of the toner matrix particles, and more preferably in the range of 3 to 20 parts by mass. Further, in such a range, the color reproducibility of the image can be ensured.

(Size of colorant particles)
The size of the colorant (particle) is not particularly limited, but the volume-based median diameter is preferably in the range of 10 to 1000 nm, more preferably in the range of 50 to 500 nm, and 80 to 80. It is particularly preferably in the range of 300 nm. Within such a range, high color reproducibility can be obtained, and it is preferable in that it is suitable for forming a small-diameter toner required for high image quality.
The volume-based median diameter of the colorant (particle) can be measured using, for example, a Microtrac (registered trademark, the same applies hereinafter) particle size distribution measuring device "UPA-150" (manufactured by Nikkiso Co., Ltd.).

<Charge control agent>
The toner matrix particles according to the present invention may contain other internal additives, if necessary. Examples of such an internal additive include a charge control agent.
Examples of the charge control agent include a metal complex (salicylic acid metal complex) made of zinc or aluminum of a salicylic acid derivative, a calixarene compound, an organic boron compound, and a fluorine-containing quaternary ammonium salt compound.
The content of the charge control agent is usually preferably in the range of 0.1 to 10 parts by mass, and in the range of 0.5 to 5 parts by mass with respect to 100 parts by mass of the binder resin in the toner. Is more preferable.

<Form of toner matrix particles>
The toner matrix particles may have a so-called single-layer structure, or may have a core-shell structure (a form in which a resin forming a shell layer is aggregated and fused on the surface of the core particles). It is also preferable that the material has a core-shell structure in that the low temperature fixing property becomes better.
The core-shell structure is not limited to a structure in which the shell layer completely covers the core particles. For example, the shell layer does not completely cover the core particles, and the core particles are exposed in places. Including those that are.
Further, from the viewpoint of improving the chargeability in a high temperature and high humidity environment, in the toner of the present invention, the crystalline polyester resins 1 and 2 are not exposed on the surface of the toner matrix particles and are contained inside the toner matrix particles. It is preferable that the amorphous resin is exposed on the surface of the toner matrix particles. As described above, the morphology of the toner matrix particles of such a toner can be controlled by the carbon number of the polyvalent carboxylic acid component and the polyhydric alcohol component forming the crystalline polyester resins 1 and 2. Further, as will be described later, when the toner matrix particles are produced by the emulsification aggregation method, the morphology of the toner matrix particles can also be controlled by the timing of addition of each resin or the like.

The morphology of the toner matrix particles (the cross-sectional structure of the core-shell structure and the position of the crystalline polyester resin) described above uses known means such as a transmission electron microscope (TEM) and a scanning probe microscope (SPM). It is possible to confirm.

<Average circularity of toner matrix particles>
From the viewpoint of improving low temperature fixability, the average circularity of the toner matrix particles is preferably in the range of 0.920 to 1.000, and more preferably in the range of 0.940 to 0.995. ..
Here, the average circularity is a value measured using "FPIA-2100" (manufactured by Sysmex Corporation). Specifically, the toner matrix particles are moistened with an aqueous surfactant solution, ultrasonically dispersed for 1 minute, and then dispersed, and then HPF is used in the measurement condition HPF (high magnification imaging) mode using "FPIA-2100". The measurement is performed at an appropriate concentration of 4000 detections. The circularity is calculated by the following formula.
Circularity = (perimeter of a circle having the same projection area as the particle image) / (perimeter of the particle projection image)
The average circularity is an arithmetic mean value obtained by adding the circularity of each particle and dividing by the total number of measured particles.

≪Particle diameter of toner matrix particles≫
Regarding the particle size of the toner matrix particles, it is preferable that the median diameter (D50) based on the volume is 3 to 10 μm. By setting the volume-based median diameter within the above range, reproducibility of fine lines and high image quality of photographic images can be achieved, and toner consumption is reduced as compared with the case of using large particle size toner. be able to. In addition, toner fluidity can be ensured. Here, the volume-based median diameter (D50) of the toner matrix particles is measured and calculated, for example, by using a device in which a computer system for data processing is connected to "Coulter Multisizer 3" (manufactured by Beckman Coulter). can do.
The volume-based median diameter of the toner matrix particles shall be controlled by the concentration of the flocculant, the amount of the solvent added, the fusion time, the composition of the resin component, etc. in the coagulation / fusion step at the time of manufacturing the toner, which will be described later. Can be done.

<External agent>
From the viewpoint of improving charging performance, fluidity, or cleaning property, the toner of the present invention preferably contains particles such as known inorganic particles and organic particles, a lubricant, and the like as an external additive on the surface of the toner matrix particles.
Various combinations of external additives may be used. Examples of the particles include inorganic oxide particles such as silica particles, alumina particles and titania particles, inorganic stearic acid compound particles such as aluminum stearate particles and zinc stearate particles, strontium titanate particles and zinc titanate particles and the like. Inorganic titanic acid compound particles and the like can be mentioned.
Examples of the lubricant include salts of zinc stearate, aluminum, copper, magnesium, calcium, etc., salts of zinc oleic acid, manganese, iron, copper, magnesium, etc., zinc palmitate, copper, magnesium, calcium, etc. Examples thereof include salts, salts such as zinc linoleic acid and calcium, and metal salts of higher fatty acids such as zinc lysynolic acid and salts such as calcium.
From the viewpoint of heat resistance and environmental stability, these external additives may be surface-treated with a silane coupling agent, a titanium coupling agent, a higher fatty acid, a silicone oil, or the like. The external additive may be used alone or in combination of two or more.
Among the above, inorganic oxide particles such as silica particles (spherical silica), alumina particles and titania particles are preferably used as the external additive.

The amount of the external additive added (the total amount when two or more types are used) is preferably in the range of 0.05 to 5% by mass, with the total mass of the toner containing the external additive as 100% by mass. It is preferably in the range of 0.1 to 3% by mass.
The particle size of the external additive is not particularly limited, but particles such as inorganic fine particles having a number average primary particle size of about 2 to 800 nm and organic fine particles having a number average primary particle size of about 10 to 2000 nm are preferable. In the present specification, the "number average primary particle diameter" is a value obtained by binarizing the scanning electron micrographs of the external additive particles, calculating the horizontal ferret diameter for 10,000 particles, and taking the average thereof. To say.

[Toner manufacturing method]
The method for producing the toner according to the present invention is not particularly limited, and examples thereof include known methods such as a kneading and pulverizing method, a suspension polymerization method, an emulsion aggregation method, a dissolution suspension method, a polyester elongation method, and a dispersion polymerization method.
Among these, it is preferable to adopt the emulsification aggregation method from the viewpoint of particle size uniformity, shape controllability, and ease of core-shell structure formation. Further, from the viewpoint that it is easy to control the crystalline polyester resin in the toner matrix particles to a desired position by utilizing the hydrophobicity of the crystalline polyester resins 1 and 2 and the release agent, the emulsion aggregation method is used. It is preferable to use it. Hereinafter, the emulsification aggregation method will be described.

<Emulsification aggregation method>
The emulsion aggregation method is a dispersion of particles of a binder resin (hereinafter, also referred to as “binding resin particles”) dispersed by a surfactant or a dispersion stabilizer, and particles of a mold release agent (hereinafter, “demolding”). It is a method of producing toner matrix particles by mixing with a dispersion liquid of (also referred to as "agent particles"), aggregating until a desired particle size is obtained, and further controlling the shape by fusing between the binder resin particles. be. Here, the particles of the binder resin may optionally contain a colorant, a charge control agent, or the like. Further, the colorant may be added to the dispersion liquid of the binder resin particles and the dispersion liquid of the release agent particles in the form of the dispersion liquid of the colorant particles.
When the toner of the present invention is produced by the emulsification aggregation method, the production method according to a preferred embodiment is
(A) A step of preparing a crystalline polyester resin particle dispersion, an amorphous resin particle dispersion, a release agent particle dispersion, and, if necessary, a colorant particle dispersion (hereinafter, also referred to as a preparation step).
(B) A step of mixing a crystalline polyester resin particle dispersion liquid, an amorphous resin particle dispersion liquid, a release agent particle dispersion liquid, and a colorant particle dispersion liquid as necessary to aggregate and fuse them (hereinafter, agglomeration).・ Also called fusion process)
including.

Hereinafter, steps (a) to (b) and steps (c) to (g) arbitrarily performed in addition to these steps will be described in detail.
(A) Preparation step The step (a) includes a crystalline polyester resin particle dispersion preparation step, an amorphous resin particle dispersion preparation step, a release agent particle dispersion preparation step, and a colorant particle dispersion, if necessary. Includes preparation steps.
(A-1) Crystallative Polyester Resin Particle Dispersion Preparation Step The crystalline polyester resin particle dispersion preparation step satisfies the relationships of the above formulas (1) to (4) as the crystalline polyester resin constituting the binder resin. Crystalline polyester resins 1 and 2 are synthesized, and each of the crystalline polyester resins 1 and 2 is dispersed in an aqueous medium in the form of fine particles to prepare a dispersion of crystalline polyester resin particles 1 and a dispersion of crystalline polyester resin particles 2. This is the process of preparation.
Since the method for producing the crystalline polyester resin is as described above, the description thereof is omitted here.

The crystalline polyester resin particle dispersion liquid is, for example, a method of performing a dispersion treatment in an aqueous medium without using a solvent, or dissolving a crystalline polyester resin in a solvent such as ethyl acetate or methyl ethyl ketone to prepare a solution, and using a disperser. Examples thereof include a method of emulsifying and dispersing the solution in an aqueous medium and then performing a solvent removal treatment.

In the present invention, the "aqueous medium" refers to a medium containing at least 50% by mass or more of water, and examples of the components other than water include organic solvents that are soluble in water, such as methanol, ethanol, and the like. Examples thereof include isopropanol, acetone, dimethylformamide, methyl cellsolve, and methanol. Of these, it is preferable to use an alcohol-based organic solvent such as methanol, ethanol, and isopropanol, which are organic solvents that do not dissolve the resin. Preferably, only water is used as the aqueous medium.

When the crystalline polyester resin contains a carboxy group in its structure, even if ammonia, sodium hydroxide, etc. are added in order to ion dissociate the carboxy group and stably emulsify the aqueous phase to promote emulsification smoothly. good. Further, the dispersion stabilizer may be dissolved in the aqueous medium, and a surfactant, resin particles, or the like may be added for the purpose of improving the dispersion stability of the oil droplets.

As the dispersion stabilizer, known ones can be used, and it is preferable to use ones soluble in acids and alkalis such as tricalcium phosphate, or from an environmental point of view, an enzyme is used. It is preferable to use one that can be decomposed. As the surfactant, known anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants can be used. Examples of the resin particles for improving the dispersion stability include polymethylmethacrylate resin particles, polystyrene resin particles, and polystyrene-acrylonitrile resin particles.

Such dispersion processing can be performed by utilizing mechanical energy, and the disperser is not particularly limited, and is not particularly limited, and is a homogenizer, a low-speed shear disperser, a high-speed shear disperser, and a frictional disperser. Machines, high-pressure jet-type dispersers, ultrasonic dispersers, high-pressure impact-type dispersers, ultimateizers, emulsification dispersers, and the like.
It is preferable to heat the solution during dispersion. The heating conditions are not particularly limited, but are usually about 60 to 200 ° C.

The volume-based median diameter of the crystalline polyester resin particles in the crystalline polyester resin particle dispersion prepared in this manner is preferably in the range of 60 to 1000 nm, and more preferably in the range of 80 to 500 nm. The median diameter can be controlled by the magnitude of mechanical energy at the time of emulsification and dispersion.

The content of the crystalline polyester resin particles in the crystalline polyester resin particle dispersion is preferably in the range of 10 to 50% by mass, more preferably in the range of 15 to 40% by mass with respect to the entire dispersion. Within such a range, the spread of the particle size distribution can be suppressed and the toner characteristics can be improved.

(A-2) Amorphous Resin Particle Dispersion Preparation Step In the amorphous resin particle dispersion preparation step, an aqueous dispersion of amorphous resin is prepared. As described above, since a vinyl resin is preferably used as the amorphous resin, a method (preparation step) for preparing a vinyl resin particle dispersion liquid will be described below.
In the step of preparing the vinyl resin particle dispersion liquid, an aqueous dispersion liquid of vinyl resin is prepared. When, for example, emulsion polymerization is carried out in an aqueous medium to obtain a vinyl resin, the liquid after the polymerization reaction can be used as it is as a vinyl resin particle dispersion liquid.
Alternatively, a method can be used in which the isolated vinyl resin is pulverized as necessary, and then the vinyl resin is dispersed in an aqueous medium using an ultrasonic disperser or the like in the presence of a surfactant. Examples of the aqueous medium and the surfactant are the same as in (a-1) above, and thus description thereof will be omitted here.

The volume-based median diameter of the vinyl resin particles in the vinyl resin particle dispersion is preferably in the range of 60 to 1000 nm, and more preferably in the range of 80 to 500 nm. The median diameter can be controlled by the magnitude of mechanical energy at the time of polymerization.

The content of the vinyl resin particles in the vinyl resin particle dispersion is preferably in the range of 10 to 50% by mass, more preferably in the range of 15 to 40% by mass with respect to the entire dispersion. Within such a range, the spread of the particle size distribution can be suppressed and the toner characteristics can be improved.

(A-3) Release Agent Particle Dispersion Solution Preparation Step The release agent particle dispersion preparation step is a step of dispersing the release agent in the form of fine particles in an aqueous medium to prepare a dispersion of release agent particles. ..
The water-based medium is as described in (a-1) above, and a surfactant, resin particles, or the like may be added to the water-based medium for the purpose of improving dispersion stability.
Dispersion of the release agent can be performed by utilizing mechanical energy, and the disperser is not particularly limited, and the one described in (a-1) above can be used. ..
The volume-based median diameter of the release agent particles in the release agent particle dispersion is preferably in the range of 10 to 300 nm.
The content of the release agent particles in the release agent particle dispersion liquid is preferably in the range of 5 to 45% by mass, and more preferably in the range of 8 to 30% by mass with respect to the entire dispersion liquid. .. Within such a range, the effects of preventing hot offset and ensuring separability can be obtained.

(A-4) Colorant Particle Dispersion Solution Preparation Step The colorant particle dispersion preparation step is a step of dispersing the colorant in the form of fine particles in an aqueous medium to prepare a colorant particle dispersion.
Since the water-based medium is as described in (a-1) above, the description thereof is omitted here. A surfactant, resin particles, or the like may be added to the aqueous medium for the purpose of improving dispersion stability.
The colorant can be dispersed by a disperser using mechanical energy, and the disperser is not particularly limited, and the disperser described in (a-1) above can be used. can.
The volume-based median diameter of the colorant particles in the colorant particle dispersion is preferably in the range of 10 to 300 nm.
The content of the colorant in the colorant particle dispersion is preferably in the range of 5 to 45% by mass, more preferably in the range of 10 to 30% by mass with respect to the entire dispersion. Within such a range, there is an effect of ensuring color reproducibility.

(B) Aggregation / fusion step In this aggregation / fusion step, the above-mentioned crystalline polyester resin particles 1 and 2, amorphous resin particles and mold release agent particles, and, if necessary, a coloring agent are used in an aqueous medium. This is a step of aggregating particles and at the same time fusing these particles.

In this step, first, a dispersion of crystalline polyester resin particles 1, a dispersion of crystalline polyester resin particles 2, an amorphous resin particle dispersion, a release agent particle dispersion, and, if necessary, a colorant particle dispersion. The liquids are mixed and these particles are dispersed in an aqueous medium. When producing clear toner, the aggregation / fusion step is performed without adding the colorant particle dispersion liquid.

Next, after the flocculant is added, the amorphous resin particles are heated at a temperature equal to or higher than the glass transition point to promote the agglomeration, and at the same time, the resin particles are fused to each other.

The flocculant is not particularly limited, but one selected from metal salts such as alkali metal salts and Group 2 metal salts is preferably used. Examples of the metal salt include monovalent metal salts such as sodium, potassium and lithium; divalent metal salts such as calcium, magnesium, manganese and copper; and trivalent metal salts such as iron and aluminum. Specific examples of the metal salt include sodium chloride, potassium chloride, lithium chloride, calcium chloride, magnesium chloride, zinc chloride, copper sulfate, magnesium sulfate, manganese sulfate, aluminum sulfate and the like. Among these, it is particularly preferable to use a divalent or trivalent metal salt because aggregation can be promoted in a smaller amount. These flocculants can be used alone or in combination of two or more.
The amount of the flocculant used is not particularly limited, but is preferably in the range of 0.1 to 20 parts by mass with respect to 100 parts by mass of the solid content of the binder resin constituting the toner matrix particles, and more preferably. It is in the range of 1 to 15 parts by mass.

In the coagulation step, it is preferable to raise the temperature rapidly by heating after adding the coagulant, and the temperature rise rate is preferably 0.05 ° C./min or more. The upper limit of the temperature rising rate is not particularly limited, but is preferably 15 ° C./min or less from the viewpoint of suppressing the generation of coarse particles due to the rapid progress of fusion.
Further, after the aggregation dispersion reaches a desired temperature, the temperature of the aggregation dispersion is maintained for a certain period of time, preferably until the volume-based median diameter becomes 4.5 to 7.0 μm, and fusion is performed. It is important to continue.

(C) Aging step This step is performed as needed, and in the aging step, the associated particles obtained by the agglomeration / fusion step are aged by thermal energy until they have a desired shape. An aging process is performed to form toner matrix particles.
Specifically, the aging treatment is carried out by heating and stirring a system in which the associated particles are dispersed, and adjusting the heating temperature, stirring speed, heating time, etc. until the shape of the associated particles becomes a desired circularity. Will be.

(D) Cooling step This step is a step of cooling the dispersion liquid of the toner matrix particles. As a condition of the cooling treatment, it is preferable to cool at a cooling rate of 1 to 20 ° C./min. The specific method of the cooling treatment is not particularly limited, and examples thereof include a method of introducing a refrigerant from the outside of the reaction vessel for cooling, a method of directly pouring cold water into the reaction system for cooling, and the like. can.

(E) Filtration / Cleaning Step In this step, the toner matrix particles are solid-liquid separated from the cooled dispersion of toner matrix particles, and the toner cake obtained by the solid-liquid separation (the toner matrix particles in a wet state is caked). This is a step of removing deposits such as a surfactant and an aggregating agent from an aggregate (aggregated into a shape) and cleaning.
The solid-liquid separation is not particularly limited, and a centrifugal separation method, a vacuum filtration method using a nutche or the like, a filtration method using a filter press or the like can be used.

(F) Drying Step This step is a step of drying the washed toner cake, and can be performed according to a drying step in a generally known method for producing toner matrix particles.
Specifically, examples of the dryer used for drying the toner cake include a spray dryer, a vacuum freeze dryer, a vacuum dryer, and the like, such as a static shelf dryer, a mobile shelf dryer, and a fluidized layer. It is preferable to use a dryer, a rotary dryer, a stirring dryer, or the like.

(G) Addition of external additive This step is a step to be performed as necessary when adding an external additive to the toner matrix particles.
As the mixing device for the external additive, a mechanical mixing device such as a Henschel mixer, a coffee mill, or a sample mill can be used.

<Developer>
The toner of the present invention can be used as a magnetic or non-magnetic one-component developer, but may be mixed with a carrier and used as a two-component developer. When the toner is used as a two-component developer, the carrier is a magnetic particle made of a conventionally known material such as a metal such as iron, ferrite or magnetite, or an alloy between the metal and a metal such as aluminum or lead. It can be used, and ferrite particles are particularly preferable. Further, as the carrier, a coat carrier in which the surface of the magnetic particles is coated with a coating agent such as a resin, or a dispersed carrier in which the magnetic fine powder is dispersed in a binder resin may be used.

The volume average particle diameter of the carrier is preferably in the range of 20 to 100 μm, and more preferably in the range of 25 to 80 μm. The volume average particle size of the carrier can be typically measured by a laser diffraction type particle size distribution measuring device "HELOS" (manufactured by Sympathic) equipped with a wet disperser.
The two-component developer can be produced by mixing the above carrier and toner using a mixing device. Examples of the mixing device include a Henschel mixer, a Nauter mixer, a V-type mixer and the like.
The blending amount of the toner in producing the two-component developer is preferably in the range of 1 to 10% by mass with respect to the total of 100% by mass of the carrier and the toner.

[Image formation method]
The image forming method according to the present invention includes forming an image forming layer on a recording medium using the toner of the present invention.
The image forming method according to the present invention is a method using the toner of the present invention, and can be suitably used for a full-color image forming method. In the full-color image forming method, four types of color developing devices for each of yellow, magenta, cyan, and black and one electrostatic latent image carrier (also referred to as "electrophotographic photosensitive member" or simply "photoreceptor") are used. A method using a 4-cycle image forming apparatus composed of the above, and a tandem image forming apparatus in which a color developing apparatus for each color and an image forming unit having an electrostatic latent image carrier are mounted for each color. Any image forming method such as the method used can be used.
When the clear toner is further used, five types of developing devices for each of yellow, magenta, cyan, black and clear and one electrostatic latent image carrier (“electrophotographic photosensitive member” or simply “photosensitive”) are used. A method using a 5-cycle image forming apparatus composed of "body"), a developing apparatus for each color containing clear toner, and an image forming unit having an electrostatic latent image carrier are mounted for each color. An image forming method such as a method using a tandem image forming apparatus can be used.

As the image forming method, an image forming method including a fixing step by a thermal pressure fixing method capable of applying pressure and heating is preferably mentioned.
In this image forming method, specifically, using the above toner, for example, an electrostatic latent image formed on a photoconductor is developed to obtain a toner image, and this toner image is used as an image support. By transferring and then fixing the toner image transferred onto the image support to the image support by a fixing process of a thermal pressure fixing method, a printed image on which a visible image is formed can be obtained.
It is preferable that the pressure is applied and the heating is performed at the same time in the fixing step, and the pressure may be applied first and then heated.

Further, the image forming method according to the present invention is suitably used in a thermal pressure fixing type image forming method. As the thermal pressure fixing type fixing device used in the image forming method according to the present invention, various known ones can be adopted. Hereinafter, as the thermal pressure fixing device, a thermal roller type fixing device and a belt heating type fixing device will be described.

(I) Thermal roller type fixing device A thermal roller type fixing device generally has a roller pair consisting of a heating roller and a pressure roller in contact with the heating roller. In the fixing device, the pressure roller is deformed by the pressure applied between the heating roller and the pressure roller, so that a so-called fixing nip portion is formed in the deformed portion.
The heating roller is generally formed by disposing a heat source such as a halogen lamp inside a core metal made of a hollow metal roller made of aluminum or the like. The core metal of the heating roller is heated by the heat source. At this time, the energization to the heat source is controlled and the temperature is adjusted so that the outer peripheral surface of the heating roller is maintained at a predetermined fixing temperature.
The fixing device has the ability to sufficiently heat and melt a toner image consisting of four toner layers (yellow, magenta, cyan and black) or five toner layers (yellow, magenta, cyan, black and clear) to mix colors. When used in an image forming apparatus for forming a required full-color image, it is preferable to have the following configuration.
That is, the fixing device includes, as a heating roller, a core metal having a high heat capacity, and an elastic layer for uniformly melting the toner image is formed on the outer peripheral surface of the core metal. preferable.

Further, the pressure roller has an elastic layer made of soft rubber such as urethane rubber and silicone rubber.
As the pressure roller, a core metal made of a hollow metal roller made of aluminum or the like and an elastic layer formed on the outer peripheral surface of the core metal may be used.
Further, when the pressure roller has a core metal, a heat source such as a halogen lamp may be arranged inside the core metal as in the heating roller. Then, the core metal may be heated by the heat source, and the energization to the heat source may be controlled and the temperature may be adjusted so that the outer peripheral surface of the pressure roller is maintained at a predetermined fixing temperature.
As the outermost layer of these heating rollers and pressure rollers, a release layer made of a fluororesin such as polytetrafluoroethylene (PTFE) or tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) is used. It is preferable to use one that is formed.
In such a thermal roller type fixing device, by rotating a pair of rollers to sandwich and convey an image support for forming a visible image to the fixing nip portion, heating by the heating roller and pressure in the fixing nip portion are applied. By doing so, the unfixed toner image is fixed on the image support.

The image forming method according to the present invention also has good low temperature fixability. Therefore, in the thermal roller type fixing device, the temperature of the heating roller can be relatively low, and specifically, the temperature can be 150 ° C. or lower. Further, the temperature of the heating roller is preferably 140 ° C. or lower, more preferably 135 ° C. or lower. From the viewpoint of excellent low-temperature fixability, the lower the temperature of the heating roller, the more preferable, and the lower limit thereof is not particularly limited, but is substantially about 90 ° C.

(Ii) Belt heating type fixing device A belt heating type fixing device generally includes, for example, a heating body made of a ceramic heater, a pressure roller, and a heat-resistant belt between these heating bodies and the pressure roller. The fixing belt is sandwiched, and the pressure roller is deformed by the pressure applied between the heating body and the pressure roller, so that a so-called fixing nip part is formed in this deformed part. Is.

As the fixing belt, a heat-resistant belt and a sheet made of polyimide or the like are used. The fixing belt is made of a heat-resistant belt or sheet made of polyimide or the like as a substrate, and fluoropolymer such as polytetrafluoroethylene (PTFE) or tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) is placed on the substrate. It may have a structure in which a release layer made of resin or the like is formed, and further, it may have a structure in which an elastic layer made of rubber or the like is provided between the substrate and the release layer. ..

In such a belt heating type fixing device, an image support on which an unfixed toner image is carried is sandwiched and conveyed together with the fixing belt between the fixing belt forming the fixing nip portion and the pressure roller. As a result, heating by the heating body via the fixing belt and application of pressure at the fixing nip portion are performed, and the unfixed toner image is fixed to the image support.
According to such a belt heating type fixing device, the heating body may be in a state where the heating body is energized only at the time of image formation to generate heat at a predetermined fixing temperature. Therefore, it is possible to shorten the waiting time from turning on the power of the image forming apparatus to the state in which the image forming is feasible. In addition, the power consumption of the image forming apparatus during standby is extremely small, which has advantages such as power saving.

As described above, the heating body, the pressure roller, and the fixing belt used as the fixing member in the fixing step are preferably those having a plurality of layer configurations.
In the belt heating type fixing device, the temperature of the heating body can be relatively low, specifically, the temperature can be 150 ° C. or lower. Further, the temperature of the heated body is preferably 140 ° C. or lower, more preferably 135 ° C. or lower. From the viewpoint of excellent low-temperature fixing property, the lower the temperature of the heated body, the more preferable, and the lower limit thereof is not particularly limited, but is substantially about 90 ° C.

(recoding media)
The recording medium (also referred to as recording material, recording paper, recording paper, etc.) may be a generally used one, as long as it holds a toner image formed by a known image forming method using, for example, an image forming apparatus. It is not particularly limited. Examples of usable image supports include plain paper from thin paper to thick paper, high-quality paper, art paper, coated printing paper such as coated paper, commercially available Japanese paper and postcard paper, and OHP. Examples thereof include plastic films for paper, cloths, various resin materials used for so-called flexible packaging, resin films formed into films thereof, labels and the like.
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In the examples, the indication of "part" or "%" represents "part by mass" or "% by mass" unless otherwise specified.

[Each analysis condition]
<Glass transition temperature of amorphous resin and melting point of crystalline resin>
The glass transition temperature (Tg) of the amorphous resin (styrene / acrylic resin) was measured using "Diamond DSC" (manufactured by PerkinElmer). First, 3.0 mg of the measurement sample (resin) was sealed in an aluminum pan and set in the sample holder of "Diamond DSC". The reference used was an empty aluminum pan. Then, the first heating process of raising the temperature from 0 ° C. to 200 ° C. at a heating rate of 10 ° C./min, the cooling process of cooling from 200 ° C. to 0 ° C. at a cooling rate of 10 ° C./min, and the heating rate of 10 ° C./min. A DSC curve was obtained under the measurement conditions (heating / cooling conditions) in which the temperature was raised from 0 ° C. to 200 ° C. in minutes in this order. Based on the DSC curve obtained by this measurement, the extension of the baseline before the rise of the first endothermic peak in the second temperature rise process and the maximum between the rising part of the first peak and the peak peak. A tangent line indicating the inclination was drawn, and the intersection was defined as the glass transition temperature (Tg).
Further, the melting point of the crystalline polyester resin is based on the DSC curve obtained in the same manner as above, and the heat absorption peak derived from the crystalline resin in the second temperature raising process (the half price width is within 15 ° C.). ) Was defined as the melting point (Tc).

<Weight average molecular weight and number average molecular weight of resin>
The molecular weight (weight average molecular weight and number average molecular weight) of each resin by GPC was measured as follows.
That is, using the apparatus "HLC-8120GPC" (manufactured by Tosoh Corporation) and the column "TSKguardcolum + TSKgelSuperHZ-M3 series" (manufactured by Tosoh Corporation), while maintaining the column temperature at 40 ° C., a flow rate of tetrahydrofuran (THF) as a carrier solvent was used. It was flushed at 0.2 mL / min. The measurement sample (resin) was dissolved in tetrahydrofuran so as to have a concentration of 1 mg / ml. The solution was prepared by treating at room temperature for 5 minutes using an ultrasonic disperser. Next, a sample solution was obtained by treating with a membrane filter having a pore size of 0.2 μm, and 10 μL of this sample solution was injected into the apparatus together with the above carrier solvent and detected using a refractive index detector (RI detector). The molecular weight distribution of the measurement sample was calculated based on the calibration curve prepared using monodisperse polystyrene standard particles. Ten points were used as the polystyrene for the calibration curve measurement.

[Preparation of crystalline polyester resin particle dispersion]
<Synthesis of crystalline polyester resin [A1]>
In a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, put 0.8 parts by mass of Ti (n-OBu) ₄ as a raw material monomer and an esterification catalyst of the following polycondensation resin, and 180 parts. The reaction was carried out at ° C. for 4 hours.
-250 parts by mass of 1,6-hexanediol-250 parts by mass of 1,14-tetradecanediocarboxylic acid (hexadecanedioic acid (COOH-C ₁₄ H ₂₈ - COOH) " Then, the temperature is raised to 210 ° C. at 10 ° C. per hour to 210 ° C. The crystalline polyester resin [A1] was obtained by reacting under reduced pressure (8 kPa) for 1 hour after holding for 5 hours. The obtained crystalline polyester resin [A1] had a number average molecular weight (Mn). It had a melting point of 4500 and a melting point of 81 ° C.

<Preparation of crystalline polyester resin particle dispersion liquid [a1]>
30 parts by mass of the crystalline polyester resin [A1] was melted and transferred to the emulsification disperser "Cavitron CD1010" (manufactured by Eurotec Ltd.) at a transfer rate of 100 parts by mass per minute. Further, at the same time as the transfer of the crystalline polyester resin [A1] in the molten state, ion exchange of 70 parts by mass of the reagent ammonia water in the aqueous solvent tank with the diluted ammonia water having a concentration of 0.37% by mass with the emulsifying disperser. (Diluted with water) was transferred at a transfer rate of 0.1 L / min while heating to 100 ° C. with a heat exchanger. Then, this emulsifying disperser is operated under the conditions of a rotor rotation speed of 60 Hz and a pressure of 5 kg / cm ² , and then ion-exchanged water is added to adjust the solid content to 20% by mass. A dispersion liquid [a1] containing crystalline polyester resin [A1] particles having a diameter of 200 nm was prepared.

<Preparation of crystalline polyester resin particle dispersion liquid [dispersion liquid a2] to [dispersion liquid a10]>
In the synthesis of the crystalline polyester resin [A1], the crystalline polyester resins [A2] to [A10] were obtained in the same manner except that the raw material monomers were changed as shown in Table II below.
Further, the crystalline polyester resin particles are similarly prepared in the same manner except that the crystalline polyester resin [A1] is changed to the crystalline polyester resins [A2] to [A10] in the preparation of the crystalline polyester resin particle dispersion liquid [a1]. Dispersions [a2] to [a10] were obtained.

[Preparation of styrene / acrylic resin particle dispersion]
5.0 parts by mass of sodium lauryl sulfate and 2500 parts by mass of ion-exchanged water are charged in a 5 L reaction vessel equipped with a stirrer, a temperature sensor, a cooling tube and a nitrogen introduction device, and the mixture is stirred at a stirring rate of 230 rpm under a nitrogen stream. While doing so, the internal temperature was raised to 80 ° C.
Next, a solution prepared by dissolving 15.0 parts by mass of potassium persulfate (KPS) in 300 parts by mass of ion-exchanged water was added, and the liquid temperature was adjusted to 80 ° C. Further, a monomer mixed solution consisting of 840.0 parts by mass of styrene (St), 288.0 parts by mass of n-butyl acrylate (BA), 72.0 parts by mass of methacrylic acid (MAA) and 15 parts by mass of n-octyl mercaptan. Was added dropwise over 2 hours. After completion of the dropping, the mixture was polymerized by heating and stirring at 80 ° C. for 2 hours to prepare a dispersion liquid [b1] of styrene / acrylic resin [B1] particles having a volume-based median diameter of 120 nm.
The glass transition temperature (Tg) of the styrene / acrylic resin [B1] was 52.0 ° C., and the weight average molecular weight (Mw) was 28,000.

[Preparation of colorant particle dispersion]
<Preparation of black colorant particle dispersion [Bk]>
・ 90 parts by mass of sodium dodecyl sulfate ・ Carbon black "Regal (registered trademark) 330R" (manufactured by Cabot)
200 parts by mass ・ 1600 parts by mass of ion-exchanged water After sufficiently dispersing the solution containing the above components with Ultratalax T50 (manufactured by IKA), the black colorant particles are treated with an ultrasonic disperser for 20 minutes. A dispersion [Bk] was prepared. For the obtained black colorant particle dispersion liquid [Bk], the median diameter based on the volume of the colorant particles was 110 nm.

<Preparation of yellow colorant particle dispersion [Ye]>
-Sodium dodecyl sulfate 90 parts by mass-C. I. Pigment Yellow 74 200 parts by mass ・ Ion-exchanged water 1600 parts by mass After sufficiently dispersing the solution containing the above components with Ultratalax T50 (manufactured by IKA), it is treated with an ultrasonic disperser for 20 minutes to make it yellow. A colorant particle dispersion [Ye] was prepared. For the obtained yellow colorant particle dispersion liquid [Ye], the median diameter based on the volume of the colorant particles was 240 nm.

<Preparation of magenta colorant particle dispersion [Ma]>
-Sodium dodecyl sulfate 90 parts by mass-C. I. Pigment Red 269 200 parts by mass ・ Ion-exchanged water 1600 parts by mass Magenta by sufficiently dispersing the solution containing the above components with Ultratalax T50 (manufactured by IKA) and then treating it with an ultrasonic disperser for 20 minutes. A colorant particle dispersion [Ma] was prepared.
For the obtained magenta colorant particle dispersion liquid [Ma], the median diameter based on the volume of the colorant particles was 200 nm.

<Preparation of cyan colorant particle dispersion [Cy]>
-Sodium dodecyl sulfate 90 parts by mass-C. I. Pigment Blue 15: 3 200 parts by mass ・ Ion-exchanged water 1600 parts by mass After sufficiently dispersing the solution containing the above components with Ultratarax T50 (manufactured by IKA), treat it with an ultrasonic disperser for 20 minutes. To prepare a cyan colorant particle dispersion [Cy]. With respect to the obtained cyan colorant particle dispersion liquid [Cy], the median diameter based on the volume of the colorant particles was 180 nm.

<Preparation of mold release agent particle dispersion [W1]>
-Paraffin wax (HNP0190, manufactured by Nippon Seiro Co., Ltd. (melting point 85 ° C))
200 parts by mass ・ 20 parts by mass of sodium dodecyl sulfate ・ 1800 parts by mass of ion-exchanged water The above materials were mixed and heated to 95 ° C., and sufficiently dispersed with Ultratarax T50 manufactured by IKA. Then, the dispersion treatment was carried out with a pressure discharge type Goulin homogenizer to prepare a release agent particle dispersion liquid [W1]. The volume-based median diameter of the release agent particles in this dispersion was 110 nm.

[Manufacturing of black toner [Bk1]]
(Agglomeration / fusion process and aging process)
Crystallized polyester resin particle dispersion liquid [a1] 38.4 parts by mass (7.7% by mass in terms of solid content), crystalline polyester resin particle dispersion liquid [a5] in a reaction vessel equipped with a stirrer, a temperature sensor and a cooling tube. ] 89.6 parts by mass (solid content equivalent 17.97 parts by mass), styrene / acrylic resin particle dispersion liquid [b1] 268.8 parts by mass (solid content equivalent 80.6 parts by mass), colorant particle dispersion liquid [Bk ] 51.9 parts by mass (5.8 parts by mass in terms of solid content), 76.8 parts by mass of the release agent particle dispersion [W1] (7.7 parts by mass in terms of solid content), and then 5 mol / L The pH (25 ° C.) was adjusted to 10 by adding an aqueous sodium hydroxide solution.
Then, an aqueous solution prepared by dissolving 12 parts by mass of magnesium chloride in 12 parts by mass of ion-exchanged water was added under stirring at 30 ° C. over 10 minutes. The temperature rise was started, the temperature of this system was raised to 80 ° C. over 60 minutes, the particle size of the associated particles was measured with "Coulter Multisizer 3" (manufactured by Beckman Coulter), and the median diameter based on the volume was determined. The stirring speed was controlled so as to be 6.0 μm. Then, an aqueous solution prepared by dissolving 45 parts by mass of sodium chloride in 180 parts by mass of ion-exchanged water was added to stop particle growth. Further, the particles were fused by heating and stirring at 80 ° C.

(Cooling process)
Then, using the measuring device "FPIA-3000" (manufactured by Sysmex) for the average circularity of the toner matrix particles (HPF detection number: 4000), when the average circularity reaches 0.957, the temperature is 5 ° C./min. It was cooled to 30 ° C. at a cooling rate.

(Filtration / cleaning process and drying process)
Next, the black toner matrix particles [XBk1] were washed by repeating the operation of solid-liquid separation, redispersing the dehydrated toner cake in ion-exchanged water, and solid-liquid separation three times, and then drying at 40 ° C. for 24 hours. Got

(Addition process of external additive)
In 100 parts by mass of the obtained toner base particles [XBk1], 0.6 parts by mass of hydrophobic silica (number average primary particle diameter = 12 nm, degree of hydrophobicity = 68) and hydrophobic titanium oxide (number average primary particle diameter = 20 nm). , Hydrophobization degree = 63) Add 1.0 part by mass and mix with a "Henshell mixer" (manufactured by Mitsui Miike Kakoki Co., Ltd.) at a rotary blade peripheral speed of 35 m / sec at 32 ° C for 20 minutes. Black toner [Bk1] was obtained by removing coarse particles using a sieve having a mesh size of 45 μm.

(Development process)
A ferrite carrier having a volume average particle diameter of 30 μm coated with a copolymer resin of cyclohexyl methacrylate and methyl methacrylate (monomer mass ratio = 1: 1) is used for black toner [Bk1], and the toner concentration is 6% by mass. By mixing in this manner, a black developer [Bk1] was obtained.

[Preparation of Black Developers [Bk2] to [Bk12]]
The black developer [Bk2] is the same as above, except that the type and amount of the dispersion liquid (resin) used in the preparation of the black developer [Bk1] are changed as shown in Table III below. -[Bk12] were prepared respectively.

In Table III, whether or not the carbon number of the polyvalent carboxylic acid component of the crystalline resin 1 and the crystalline resin 2 and the carbon number of the polyhydric alcohol component satisfy the above formulas (1) to (4) is satisfied. , ○ or ×.

[Preparation of Yellow Developers [Ye1] to [Ye12]]
In the production of the black developer [Bk1], the types and amounts of the dispersion liquid (resin) used, and the types and amounts of the colorants used were changed as shown in Table IV below. In the same manner, yellow developers [Ye1] to [Ye12] were prepared.

[Preparation of Magenta Developers [Ma1] to [Ma12]]
In the production of the black developer [Bk1], the types and amounts of the dispersion liquid (resin) used, and the types and amounts of the colorants used were changed as shown in Table V below. In the same manner, magenta developers [Ma1] to [Ma12] were prepared.

[Preparation of Cyan Developers [Cy1] to [Cy12]]
In the production of the black developer [Bk1], the types and amounts of the dispersion liquid (resin) used, and the types and amounts of the colorants used were changed as shown in Table VI below. In the same manner, cyan developeres [Cy1] to [Cy12] were prepared.

[evaluation]
<Low temperature fixability>
The fixing device of the copying machine "bizhub PRESS (registered trademark) C1070" (manufactured by Konica Minolta Co., Ltd.) was modified so that the surface temperature (fixing temperature) of the heating roller could be changed in the range of 120 to 180 ° C. Each developer set was loaded into the copier with the combinations of the developing agents shown in Table VII below and evaluated.
First, in an environment of normal temperature and humidity (temperature 20 ° C, humidity 50% RH), black toner, yellow toner, magenta toner and cyan toner are applied on A4 size high-quality paper "CF paper" (manufactured by Konica Minolta Co., Ltd.). The adhesion amount of the superimposed images was set to 10.0 g / m ² . At this time, it was set so that there was no difference in the amount of adhesion of the black toner, the yellow toner, the magenta toner, and the cyan toner. After that, a fixing experiment for fixing a four-color image having a size of 100 mm × 100 mm was repeated from 120 ° C. to 180 ° C. while changing the set fixing temperature from 120 ° C. in 1 ° C. increments.
The printed matter obtained at each fixing temperature obtained above was visually confirmed, and the lowest temperature at which all the toner did not adhere to the fuser and was fixed to the paper was defined as the minimum fixing temperature (° C.), and the rank was evaluated as follows.
-Evaluation criteria-
◯: Less than 140 ° C. Δ: 140 ° C. or higher and lower than 150 ° C. ×: 150 ° C. or higher ○ and Δ are acceptable levels.

<Heat-resistant storage of toner>
For each of the prepared toners, take 0.5 g of each toner in a 10 mL glass bottle with an inner diameter of 21 mm, close the lid, and shake it 600 times at room temperature using a shaker "Tap Denser KYT-2000" (manufactured by Seishin Corporation). bottom. Then, it was left for 2 hours in an environment of a temperature of 55 ° C. and a humidity of 35% RH with the lid open.
Next, place the toner on a sieve of 48 mesh (opening 350 μm), being careful not to crush the toner aggregates, set it in a “powder tester” (manufactured by Hosokawa Micron), and use a holding bar and a knob nut. Fixed. After adjusting the vibration intensity to a feed width of 1 mm and applying vibration for 10 seconds, the ratio (mass%) of the amount of toner remaining on the sieve was measured, and the toner aggregation rate was calculated by the following formula (A).
Formula (A): Toner aggregation rate (%) = (mass of residual toner on sieve (g)) /0.5 (g) × 100)
Similar measurements are made at temperatures of 57.5 ° C and 60 ° C, respectively, and plotted with the X-axis as the temperature and the Y-axis as the toner aggregation rate. Of the temperatures 55 ° C, 57.5 ° C, and 60 ° C, an approximate straight line is drawn between the two temperatures sandwiching the region where the toner aggregation rate is 50%, and the temperature at which the toner aggregation rate is 50% is calculated from the interpolation. .. The temperature at that time is defined as the heat resistant temperature. The rank was evaluated as follows.
-Evaluation criteria-
◯: 58 ° C or higher Δ: 57 ° C or higher and lower than 58 ° C ×: less than 57 ° C ○ and Δ are acceptable levels.

<Toner matrix fluidity>
After 20.0 g of toner before image evaluation is placed on a 120-mesh sieve and dropped at a vibration intensity of 6 for 60 seconds, the amount of residual toner on the sieve is measured, and the toner sieve is formulated by the following formula (B). The passing rate was calculated and ranked as follows.
Formula (B): Toner sieve passing rate (%) = (mass of passing toner on the sieve (g)) / 20.0 (g) × 100)
-Evaluation criteria-
◯: 60% or more Δ: 50% or more and less than 60% ×: less than 50%
○ and △ are the pass levels.

In Tables I to III, "the number of carbon atoms of the polyvalent carboxylic acid", "the number of carbon atoms C1 (acid)" and "the number of carbon atoms C2 (acid)" mean the number of carbon atoms of the carboxy group not including carbon.

From the above results, it is recognized that when the toner of the present invention is used, it is superior in low temperature fixing property, heat storage property and fluidity as compared with the toner of the comparative example.

Claims (5)

A toner for developing an electrostatic charge image containing at least toner matrix particles,
The toner matrix particles contain an amorphous resin, a mold release agent, a crystalline resin 1, and a crystalline resin 2.
The crystalline resin 1 and the crystalline resin 2 are crystalline polyester resins containing a polyhydric alcohol and a polyvalent carboxylic acid as monomer components.
The carbon number of the polyvalent alcohol component of the crystalline resin 1 (C1 (alcohol)), the carbon number of the polyvalent alcohol component of the crystalline resin 2 (C2 (alcohol)), and the polyvalent value of the crystalline resin 1. The carbon number of the carboxylic acid component (C1 (acid)) and the carbon number of the polyvalent carboxylic acid component of the crystalline resin 2 (C2 (acid)) satisfy the relationship of the following formulas (1) to (4). However, the carbon number of the polyvalent carboxylic acid component is a carbon number that does not contain carbon of a carboxy group, and is a toner for static charge image development.
C1 (acid)> C1 (alcohol) ... Equation (1)
C2 (acid)> C2 (alcohol) ... Equation (2)
C1 (alcohol) ≠ C2 (alcohol) ... Equation (3)
12 ≤ C1 (acid) = C2 (acid) ≤ 14 ... Equation (4) The static charge according to claim 1, wherein the content of at least the crystalline resin 1 and the crystalline resin 2 is in the range of 2.0 to 30% by mass with respect to the amorphous resin. Toner for image development. The carbon number (C1 (alcohol)) of the polyhydric alcohol component of the crystalline resin 1 and the carbon number (C2 (alcohol)) of the polyhydric alcohol component of the crystalline resin 2 have the relationship of the following formula (5). The static charge image developing toner according to claim 1 or 2, wherein the toner is satisfied.
| C1 (alcohol) -C2 (alcohol) | ≧ 2 ... Equation (5) At least the number of carbon atoms (C1 (alcohol)) of the crystalline resin 1 and the number of carbon atoms (C2 (alcohol)) of the polyhydric alcohol component of the crystalline resin 2 satisfy the following formula (8), and the mass ratio thereof. The static charge image according to any one of claims 1 to 3, wherein the value of (crystalline resin 1 / crystalline resin 2) is in the range of 60/40 to 1/99. Development toner.
C1 (alcohol)> C2 (alcohol) ... Equation (8) The toner for static charge image development according to any one of claims 1 to 4, wherein the amorphous resin contains a styrene / acrylic resin.