JP2019086604A - Toner for electrostatic charge image development - Google Patents

Abstract

To provide a toner for electrostatic charge image development that is excellent in low-temperature fixability and heat-resistant storage property and also has fluidity.SOLUTION: In a toner of the present invention, a toner base particle contains an amorphous resin, a mold release agent, a crystalline resin 1, and a crystalline resin 2; the crystalline resins 1 and 2 are a crystalline polyester resin; the number of carbon atoms in a polyhydric alcohol component of the crystalline resin 1 (C1(alcohol)), the number of carbon atoms in a polyhydric alcohol component of the crystalline resin 2 (C2(alcohol)), the number of carbon atoms in a polyvalent carboxylic acid component of the crystalline resin 1 (C1(acid)), and the number of carbon atoms in a polyvalent carboxylic acid component of the crystalline resin 2 (C2(acid)) satisfy the relationships of the formulas (1) to (4). Formula (1): C1(acid)>C1(alcohol); formula (2): C2(acid)>C2(alcohol); formula (3): C1(alcohol)≠C2(alcohol); formula (4): C1(acid)=C2(acid).SELECTED DRAWING: None

Description

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

In recent years, in an electrophotographic image forming apparatus, a toner for developing an electrostatic charge image which is thermally fixed at a lower temperature in order to further save energy for the purpose of increasing printing speed, reducing environmental load, etc. , Also simply referred to as "toner". In such a toner, it is necessary to lower the melting temperature and the melt viscosity of the binder resin, and by adding a crystalline resin such as a crystalline polyester resin, a toner having improved low-temperature fixability is proposed. ing.
However, in a toner containing a crystalline resin, if the crystalline resin is heated to a temperature higher than the melting point of the crystalline resin at the time of production of the toner, the crystalline resin becomes compatible with the amorphous resin even at the time of production. Was aggravated by

As a means for improving the heat-resistant storage stability of the toner having such a configuration, for example, Patent Document 1 discloses that two types of crystalline polyester resins are caused to have different domains, thereby forming crystalline polyester resin and vinyl resin. It has been reported that the trade-off between low temperature fixability and heat resistant storage stability can be solved because the incompatibility can be controlled.
However, due to variations in the particle size distribution of the crystalline polyester resin, there is a risk that the heat resistant storage stability may fluctuate due to the collapse of the compatibility / incompatibility relationship with other resins, so that the heat resistant storage stability is surely There is a problem that it can not secure.

In Patent Document 2, when two types of crystalline polyester resins are included, when paper such as thin paper duplex printing tends to be fixed at high temperature, resin A and resin B melt, but at this time, the SP value close to that is In that case, it has been reported that the two resins become compatible with each other and behave as an intermediate crystalline polyester resin of the two resins, and secure low temperature fixing and heat resistant storage stability.
However, since it is not sufficient to suppress the surface exposure of the crystalline resin, aggregation and fusion occur between toner particles due to environmental changes, so that the low temperature fixing and the heat resistant storage stability can not be simultaneously achieved. Was left.

In patent document 3, it is implement | achieved by making SP value of a styrene acrylic resin and a dispersing agent into 0.10 or less as a means to disperse | distribute crystalline polyester in a styrene acrylic resin. At normal temperature, the styrene-acrylic resin and the modified polyester resin have a phase separation structure to maintain the softening point and obtain high heat-resistant storage stability. In addition, the use of the dispersing agent highly disperses the modified polyester resin in the styrene / acrylic resin, and the fixing unevenness is suppressed, so that it is possible to obtain an in-plane uniform gloss.
However, since it is not sufficient to suppress the surface exposure of the crystalline resin, aggregation and fusion between toner particles occur due to environmental changes, so that it is impossible to simultaneously ensure low temperature fixability and heat resistant storage stability. There was a problem left.

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

  The present invention has been made in view of the above problems and circumstances, and the problem to be solved is to provide an electrostatic charge image developing toner having excellent low temperature fixability and heat resistant storage stability as well as toner fluidity. is there.

In the process of examining the cause of the above problems and the like by the inventor in order to solve the above problems, the carbon number of the polyhydric alcohol component and the carbon number of the polyhydric carboxylic acid component of the two crystalline polyester resins are By controlling so as to satisfy a specific relationship, the present inventors have found that it is possible to provide a toner for developing an electrostatic charge image, which is excellent in low temperature fixability and heat resistant storage stability, and also has toner fluidity.
That is, the above-mentioned subject concerning the present invention is solved by the following means.
1. A toner for developing an electrostatic charge image containing at least toner base particles;
The toner base particles contain an amorphous resin, a releasing 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 (C1 (alcohol)) of the polyhydric alcohol component of the crystalline resin 1, the carbon number (C2 (alcohol)) of the polyhydric alcohol component of the crystalline resin 2, and the polyvalent of the crystalline resin 1 The carbon number (C1 (acid)) of the carboxylic acid component and the carbon number (C2 (acid)) of the polyvalent carboxylic acid component of the crystalline resin 2 satisfy the relationship of the following formulas (1) to (4) A toner for developing an electrostatic charge image characterized by
C1 (acid)> C1 (alcohol) formula (1)
C2 (acid)> C2 (alcohol) formula (2)
C1 (alcohol) ≠ C2 (alcohol) formula (3)
C1 (acid) = C2 (acid) Formula (4)

  2. The electrostatic 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 non-crystalline resin. Toner for image development.

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 a relationship of the following formula (5) The toner for electrostatic image development according to claim 1 or 2, characterized in that:
| C 1 (alcohol) -C 2 (alcohol) | ≧ 2 Formula (5)

4. 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 represented by the following formula (6) The toner for developing an electrostatic charge image according to any one of Items 1 to 3, which satisfies the relationship of (7).
C1 (acid) 10 10 ... Formula (6)
C2 (acid) 10 10 ... Formula (7)

5. At least the carbon number (C1 (alcohol)) of the crystalline resin 1 and the carbon number (C2 (alcohol)) of the polyhydric alcohol component of the crystalline resin 2 satisfy the following formula (8), and the mass ratio thereof The electrostatic charge image according to any one of Items 1 to 4, wherein the value of (Crystalline Resin 1 / Crystalline Resin 2) is in the range of 60/40 to 1/99. Developing toner.
C1 (alcohol)> C2 (alcohol) formula (8)

  6. The toner for electrostatic image development according to any one of claims 1 to 5, wherein the toner base particles have a core-shell structure.

  7. The toner for electrostatic image development according to any one of items 1 to 6, wherein the amorphous resin contains a styrene-acrylic resin.

According to the above-mentioned means of the present invention, it is possible to provide a toner for developing an electrostatic charge image, which is excellent in low temperature fixability and heat resistant storage stability and also has toner fluidity.
The mechanism for expressing the effect of the present invention or the mechanism of action is not clear but is presumed as follows.
By setting the carbon number of the carboxylic acid component to be greater than the carbon number of the alcohol component in the crystalline resins 1 and 2 (the above formulas (1) and (2)), the compatibility with the noncrystalline resin is increased, It is possible to suppress the crystalline resin from being exposed on the surface of the toner base particles, and it is excellent in low-temperature fixability. That is, by increasing the carbon number of the carboxylic acid component, the SP value decreases, and it becomes easy to be compatible with the amorphous resin at the time of fixing.
Further, by using two types of crystalline resins 1 and 2 (the above formulas (3) and (4)), one crystalline resin 1 improves the compatibility with the release agent, and the high temperature of the release agent Bleed out during storage can be suppressed, and the other crystalline resin 2 can enhance the compatibility with the amorphous resin.
Further, by making the carbon numbers 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 resin 1 and 2 can be enhanced. In addition, when the degree of crystallization is equal, 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, it is possible to maximize the effect of the composition contained in the toner. Specifically, since the crystalline resin is more compatible with the amorphous resin and the compatibility with the releasing agent is also further enhanced, the toner excellent in low temperature fixability, heat resistant storage property and toner fluidity is obtained. Can be provided.

The toner for electrostatic charge image development of the present invention is a toner for electrostatic charge image development containing at least toner base particles, and the toner base particles comprise an amorphous resin, a releasing agent, and a crystalline resin 1. 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, and the polyvalent resin of the crystalline resin 1 Carbon number of alcohol component (C1 (alcohol)), carbon number of polyhydric alcohol component of the crystalline resin 2 (C2 (alcohol)), carbon number of polyhydric carboxylic acid component of the crystalline resin 1 (C1) It is characterized in that (acid) and the carbon number (C2 (acid)) of the polyvalent carboxylic acid component of the crystalline resin 2 satisfy the relationships of the above formulas (1) to (4).
This feature is a technical feature that is common to or corresponds to the invention according to the present embodiment.

  As an embodiment of the present invention, low-temperature fixing that at least the content of the crystalline resin 1 and the crystalline resin 2 is in the range of 2.0 to 30% by mass with respect to the non-crystalline resin It is preferable at the point which becomes favorable.

  Further, 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 are represented by the above formula (5) Satisfying the relationship is more effective in containing two types of crystalline resins, and is preferable in terms of low-temperature fixability, heat-resistant storage stability and toner fluidity.

  Further, 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 represented by the above formula (6) It is preferable to satisfy the relationship of (7) and (7) in that the compatibility with the release agent is enhanced and the bleed out of the release agent at the time of high temperature storage of the toner is suppressed.

  Further, at least the carbon number (C1 (alcohol)) of the crystalline resin 1 and the carbon number (C2 (alcohol)) of the polyhydric alcohol component of the crystalline resin 2 satisfy the formula (8), and the mass thereof Two crystalline resins are contained so that the ratio value (crystalline resin 1 / crystalline resin 2) is in the range of 60/40 to 1/99, and toner fluidity can be obtained without impairing the toner performance. It is preferable at the point which can ensure.

  Further, it is preferable that the toner base particles have a core-shell structure in that the low-temperature fixability is further improved.

  Further, it is preferable that the non-crystalline resin contains a styrene-acrylic resin in that the toner can be manufactured inexpensively.

  BEST MODE FOR CARRYING OUT THE INVENTION The present invention, its components, and modes and modes for carrying out the present invention will be described below. In the present application, “to” is used in the meaning including the numerical values described before and after that as the lower limit value and the upper limit value.

[Toner for electrostatic image development]
The toner of the present invention is a toner for developing an electrostatic charge image containing at least toner base particles, wherein the toner base particles comprise an amorphous resin, a releasing agent, a crystalline resin 1 and a crystalline resin 2. Contains and
A crystalline resin 1, a mold release agent, a crystalline resin 1, and a crystalline resin 2 are contained, and the crystalline resin 1 and the crystalline resin 2 contain a polyhydric alcohol and a polyhydric carboxylic acid as a monomer component. And 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; 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 represented by the following formula (1) It is characterized by satisfying the relationship of (4).
C1 (acid)> C1 (alcohol) formula (1)
C2 (acid)> C2 (alcohol) formula (2)
C1 (alcohol) ≠ C2 (alcohol) formula (3)
C1 (acid) = C2 (acid) Formula (4)

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

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

  In the present invention, toner base particles to which an external additive is added are called toner particles, and an aggregate of toner particles is called toner. Generally, toner base particles can be used as toner particles as they are, but in the present invention, toner base particles to which an external additive is added are used as toner particles.

<Crystalline 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 a polyhydric alcohol and a polyvalent carboxylic acid as monomer components.
Here, the reason for using the two types of crystalline resins 1 and 2 is to achieve both the manufacturability and the performance as a toner.
By mixing the crystalline resins 1 and 2 with the amorphous resin described in detail below, the crystalline resin 2 becomes compatible with the amorphous resin at the time of heat fixing. As a result, low temperature fixing of the toner can be achieved, and energy saving can be achieved.

  In the present invention, the crystalline resin refers to a resin having a clear endothermic peak instead of a stepwise endothermic change in differential scanning calorimetry (DSC). A clear endothermic peak specifically means a peak whose half-width of the endothermic peak is within 15 ° C. when measured at a heating 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 relationships of the above formulas (1) to (4), and conventionally known crystalline resins in the technical field can be used. It can be used.
Specific examples thereof include crystalline polyester resins, crystalline polyurethane resins, crystalline polyurea resins, crystalline polyamide resins, crystalline polyether resins and the like. The crystalline resin may be used alone or in combination of two or more.
Among them, the crystalline resin according to the present invention is preferably a crystalline polyester resin. Here, “crystalline polyester resin” is obtained by a polycondensation reaction of a carboxylic acid having two or more valences (polyvalent carboxylic acid) and a derivative thereof with an alcohol having two or more valences (polyhydric alcohol) and a derivative thereof Among known polyester resins, it is a resin that satisfies the above-mentioned endothermic 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 such a point of view, the temperature 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 the examples described later.

  In the present invention, the low-temperature fixability is such 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 non-crystalline resin. It is preferable at the point which becomes favorable, and it is more preferable that it is about 20 mass%.

(Regarding Formula (1) and Formula (2))
C1 (acid)> C1 (alcohol) formula (1)
C2 (acid)> C2 (alcohol) formula (2)
The two crystalline resins 1 and 2 are characterized in that they satisfy the relationships of the above formulas (1) and (2). Thereby, the carbon number of the carboxylic acid component is larger than the carbon number of the alcohol component. When the carbon number of the carboxylic acid component is increased, the SP value is decreased, and it becomes easy to be compatible with the amorphous resin at the time of fixing. As a result, the low temperature fixability is improved.

(Regarding Formula (3) and Formula (4))
C1 (alcohol) ≠ C2 (alcohol) formula (3)
C1 (acid) = C2 (acid) Formula (4)
It is characterized in that the two types of crystalline resins 1 and 2 satisfy the relationship of the above formulas (3) and (4). Thereby, the compatibility with the mold release agent can be enhanced with one crystalline resin 1, and bleed out at the time of high temperature storage of the mold release agent can be suppressed, and with the other crystalline resin 2, amorphous resin can be used. Compatibility can be enhanced.
Further, by making the carbon numbers 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 It can be enhanced. In addition, when the degree of crystallization is equal, 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 a relationship of the following formula (5) It is preferable to satisfy the conditions, because the effect of containing two kinds of crystalline resins is enhanced, and the low temperature fixability, the heat resistant storage stability and the toner fluidity are preferable.
| C 1 (alcohol) -C 2 (alcohol) | ≧ 2 Formula (5)
(Regarding Formula (6) and Formula (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 represented by the following formula (6) Satisfying the relationship of (7) is preferable from the viewpoint of enhancing the compatibility with the releasing agent and suppressing the bleeding out of the releasing agent at the time of high temperature storage of the toner.
C1 (acid) 10 10 ... Formula (6)
C2 (acid) 10 10 ... Formula (7)

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

(Polyhydric alcohol component)
Examples of polyhydric alcohol components constituting the crystalline polyester resins 1 and 2 according to the present invention include oxalic acid (ethane diacid), malonic acid (propane diacid), succinic acid (butane diacid), glutaric acid Pentanedioic acid), adipic acid (hexanedioic acid), pimelic acid (heptanedioic acid), suberic acid (octanedioic acid), azelaic acid (nonanedioic acid), sebacic acid (decanedioic acid), 1,9-nonane Dicarboxylic acid (undecanedioic acid), 1,10-decanedicarboxylic acid (dodecanedioic acid), 1,11-undecanedicarboxylic acid (tridecanedioic acid), 1,12-dodecanedicarboxylic acid (tetradecanedioic acid), 1, 13 -Tridecanedicarboxylic acid (pentadecanedioic acid), 1,14-tetradecanedicarboxylic acid (hexadecanedioic acid), etc. can be used. Also, these lower alkyl esters and acid anhydrides may be used. The polyvalent carboxylic acids may be used alone or in combination of two or more.

(Polyvalent carboxylic acid component)
As polyvalent carboxylic acid components constituting crystalline polyester resins 1 and 2 according to the present invention, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5- Pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, neopentyl glycol And aliphatic diols such as 1,4-butenediol; and trivalent or higher polyhydric alcohols such as glycerin, pentaerythritol, trimethylolpropane and sorbitol. Also, these derivatives may be used. The said polyhydric alcohol may be used individually by 1 type, and may be used in combination of 2 or more type.

In the present invention, preferable combinations of the crystalline polyester resin 1 and the crystalline polyester resin 2 are as follows. That is, in the following table, a combination of crystalline resin 1 (polyvalent carboxylic acid, polyhydric alcohol) and crystalline resin 2 (polyvalent carboxylic acid, polyhydric alcohol) arranged in the same row is preferable.

  The number average molecular weight (Mn) of the crystalline polyester resin is not particularly limited, but is preferably in the range of 1500 to 25,000, and more preferably in the range of 3000 to 20000. With 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 the examples.

The method for producing the crystalline polyester resin is not particularly limited, and the crystalline polyester resin can be produced by polycondensation (esterification) of the polyhydric alcohol and the polyvalent carboxylic acid using a known esterification catalyst.
Examples of catalysts usable in the production of crystalline polyester resins include alkali metal compounds such as sodium and lithium; compounds containing Group 2 elements such as magnesium and calcium; aluminum, zinc, manganese, antimony, titanium, tin, Metal compounds such as zirconium and germanium; phosphorous compounds; phosphoric compounds; and amine compounds. In view of availability and the like, dibutyltin oxide, tin octylate, tin dioctylate, salts thereof, tetranormal butyl titanate (tetrabutyl orthotitanate), 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 the polycondensation (esterification) is not particularly limited, but is preferably in the range of 150 to 250 ° C. Moreover, the time of polycondensation (esterification) is not particularly limited, but is preferably in the range of 0.5 to 15 hours. During the polycondensation, if necessary, the pressure in the reaction system may be reduced.

The toner of the present invention contains an amorphous resin in addition to the crystalline polyester resins 1 and 2 as a binder resin.
In the toner of 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 non-crystalline resin. It is preferable at the point which becomes favorable. 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, preferably in the range of 3 to 20% by mass, with respect to the entire binder resin. Is more preferably, and particularly preferably 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, the compatibility with the non-crystalline resin appropriately plasticizes 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, in the toner, the crystalline polyester resins 1 and 2 become difficult to be exposed on the surface of the toner base particles, and chargeability is further improved. Even under a high temperature and high humidity environment, the image density unevenness is suppressed, and the image density is also improved.

In addition, the content of the crystalline polyester resin in the toner of the present invention is amorphous polyester resin 1 and crystalline polyester resin 2 respectively in view of the improvement of low-temperature fixability and suppression of the environmental dependency of image density unevenness. It is preferably in the range of 1 to 30% by mass, more preferably in the range of 3 to 20% by mass, and more preferably 6 to 15% by mass, based on the total mass of the resin and the release agent. It is particularly preferred to be within the range. Within such a range, the low temperature fixability is excellent, and the density of the formed image is also improved.
The structure (constituent unit) of the crystalline polyester resins 1 and 2 and the content (ratio) of each constituent component (each constituent unit) are, for example, NMR measurement, methylation reaction Py-GC / MS measurement Can be specified by

<Amorphous resin>
The amorphous resin is preferably a main component of the binder resin contained in the toner.
When the binder resin contains an amorphous resin as a main component, the amorphous resin is easily present on the surface of the toner base particles. As a result, the chargeability of the toner base particles can be improved due to the high electrical resistance of the amorphous resin.
Here, "main component" means that the resin is the resin with the highest content ratio among binder resins. The amorphous resin is preferably 50% by mass or more, more preferably in the range of 70 to 99% by mass, and more preferably in the range of 80 to 97% by mass, with respect to the entire binder resin. Is even more preferable, and it is particularly preferable to be in the range of 83 to 94% by mass.
In addition, the content of the amorphous resin is in the range of 65 to 95% by mass based on the total mass of the crystalline polyester resins 1 and 2, the amorphous resin, and the releasing agent. Preferably, 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 fixability is excellent, and the density of the formed image is also improved.

In the present invention, the amorphous resin is a resin having no melting point and having 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 scanning calorimeter (DSC), and specifically, it is measured by the method described in the examples. Those skilled in the art can control the glass transition temperature according to the composition of the resin.
As the amorphous resin, conventionally known amorphous resins in the technical field may be used. Among them, amorphous polyester resin or 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 charge amount.

(Vinyl resin)
The vinyl resin is a resin obtained by polymerization using at least a vinyl monomer. Specifically as a vinyl resin, an acrylic resin, a styrene acryl copolymer resin (styrene acryl resin), etc. are mentioned.
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 charge amount. The vinyl resins may be used alone or in combination of two or more.
As a vinyl monomer which forms a vinyl resin, 1 type (s) or 2 or more types selected from the following can be used.

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

(2) (meth) acrylic acid ester monomer methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate (n-butyl (meth) acrylate), isopropyl (meth) acrylate Isobutyl (meth) acrylate, t-butyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, ( Phenyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate and derivatives thereof and the like.

(3) Vinyl esters Vinyl propionate, vinyl acetate, vinyl benzoate and the like.

(4) Vinyl ethers Vinyl methyl ether, vinyl ethyl ether and the like.

(5) Vinyl ketones Vinyl methyl ketone, vinyl ethyl ketone, vinyl hexyl ketone and the like.

(6) N-vinyl compounds N-vinylcarbazole, N-vinyl indole, N-vinyl pyrrolidone and the like.

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

Moreover, as a vinyl monomer, it is preferable to use the monomer which has ionic dissociative groups, such as a carboxy group, a sulfonic acid group, and a phosphoric acid group, for example. Specifically, there are the following.
Examples of the monomer having a carboxy group include acrylic acid, methacrylic acid, maleic acid, itaconic acid, cinnamic acid, fumaric acid, monoalkyl ester of maleic acid and monoalkyl ester of itaconic acid.
Moreover, as a monomer which has a sulfonic acid group, styrene sulfonic acid, allyl sulfosuccinic acid, 2-acrylamido 2-methyl propane sulfonic acid etc. are mentioned.
Furthermore, as a monomer having a phosphoric acid group, acid phosphoxoxyethyl methacrylate and the like can be mentioned.

Furthermore, polyfunctional vinyls may be used as the vinyl monomer to form a vinyl resin having a crosslinked structure.
As polyfunctional vinyls, divinylbenzene, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, neopentyl glycol Diacrylate etc. are mentioned.

The method for producing the vinyl resin is not particularly limited, and bulk polymerization, solution using any polymerization initiator such as peroxide, persulfate, persulfide or azo compound which is usually used for polymerization of the above-mentioned monomers Examples of the method include polymerization by a known polymerization method such as polymerization, emulsion polymerization, mini-emulsion method and dispersion polymerization.
In addition, generally used chain transfer agents can be used for the purpose of adjusting molecular weight. The chain transfer agent is not particularly limited, and examples thereof include alkyl mercaptan and mercapto fatty acid ester.
Moreover, it is preferable that the molecular weight measured by the gel permeation chromatography (GPC) of vinyl resin is in the range of 10000-100000 in a weight average molecular weight (Mw).
The non-crystalline resin according to the present invention preferably contains a vinyl resin, and more preferably contains a styrene-acrylic resin. A vinyl resin (in particular, a styrene-acrylic resin) has less functional groups with high polarity and a low hygroscopicity as compared with the amorphous polyester resin, so that the transferability in a high temperature and high humidity environment becomes good. Therefore, the environmental dependency of the image density unevenness can be easily reduced. In addition, good image density can be obtained regardless of 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 dependency of the image density unevenness, the content of the styrene-acrylic resin is preferably 50% by mass or more with respect to the total amount of the amorphous resin, and 80% % 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, polyethylene wax, polyolefin wax such as polypropylene wax, branched chain such as microcrystalline wax, etc. Hydrocarbon wax, paraffin wax, long chain hydrocarbon wax such as sasol wax, dialkyl ketone wax such as distearyl ketone, carnauba wax, montan wax, behenyl behenate, trimethylolpropane tribehenate, pentaerythritol tetratetra Behenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18-octadecanediol distearate, tristearyl trimellitate, distearyl maleate, etc. Le wax, ethylenediamine behenyl amide, an amide-based waxes such as trimellitic acid tristearyl amide.
Among them, in order to facilitate the presence of the crystalline polyester resin in the toner base particles and to improve the chargeability in the toner of the present invention, it is preferable to use a hydrocarbon wax having high hydrophobicity as the releasing agent. .

The content of the releasing agent is preferably in the range of 2 to 20% by mass, more preferably in the range of 3 to 18% by mass, and more preferably 5 to 15% by mass with respect to the total amount of the binder resin. It is particularly preferred to be within the range.
The content of the releasing 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 releasing 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 fixability is excellent, and the density of the formed image is also improved.
The melting point of the releasing agent is preferably in the range of 50 to 95 ° C. from the viewpoint of the low temperature fixing property and the releasing property of the toner in the electrophotographic system.

<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 as described below.

(Black colorant)
The colorant used for the black toner includes carbon black.
As carbon black, channel black, furnace black, acetylene black, thermal black, lamp black or the like is used.
Furthermore, the black toner may further contain magnetic substances, dyes, other pigments, etc. in addition to carbon black. As the magnetic substance, ferromagnetic metals such as iron, nickel, or cobalt, alloys containing these metals, ferrite, or compounds of ferromagnetic metals such as magnetite can be used. Moreover, titanium black, aniline black, etc. can be used as another pigment.

(Yellow colorant)
The colorant for orange or yellow used in the yellow toner is not particularly limited. For example, as organic pigments, 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.
Moreover, as a 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. These colorants may be used alone or in combination of two or more.

(Magenta colorant)
The colorant for magenta or red used in the magenta toner is not particularly limited. For example, as organic pigments, 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.
Moreover, as a 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. Solvent Red 122 and the like. These colorants may be used alone or in combination of two or more.

(Cyan colorant)
The colorant for green or cyan used for the cyan toner is not particularly limited. For example, as the 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.
Moreover, as a 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. Solvent Blue 95 and the like. These colorants may be used alone or in combination of two or more.

(Colorant content)
The content of each coloring agent is preferably in the range of 1 to 30 parts by mass, and more preferably in the range of 3 to 20 parts by mass with respect to 100 parts by mass of toner base particles. In addition, color reproducibility of the image can be secured in such a range.

(Size of colorant particles)
The size of the colorant (particles) is not particularly limited, but the median diameter on a volume basis is preferably in the range of 10 to 1000 nm, and more preferably in the range of 50 to 500 nm, It is particularly preferred to be 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 necessary for high image quality.
The volume-based median diameter of the colorant (particles) can be measured, for example, using Microtrac (registered trademark, the same applies hereinafter) particle size distribution measuring apparatus “UPA-150” (manufactured by Nikkiso Co., Ltd.).

<Charge control agent>
The toner base particles according to the present invention may contain other internal additives as required. Such internal additives include charge control agents.
Examples of charge control agents include metal complexes of salicylic acid derivatives with zinc and aluminum (salicylic acid metal complexes), calixarene compounds, organic boron compounds, and fluorine-containing quaternary ammonium salt compounds.
The content of the charge control agent is preferably in the range of usually 0.1 to 10 parts by mass and preferably 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 preferred.

<Form of Toner Base Particles>
The toner base particles may have a so-called single-layer structure or a core-shell structure (a form in which a resin forming a shell layer on the surface of the core particles is aggregated and fused). It is preferable to have a core-shell structure in that the low temperature fixability is better.
The core-shell structure is not limited to the structure in which the shell layer completely covers the core particle, and for example, the shell layer does not completely cover the core particle, and the core particle is exposed in some places. Including those that exist.
In addition, 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 base particles, and are contained inside the toner base particles. Preferably, the amorphous resin is in a form exposed on the surface of the toner base particle. The form of the toner base 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 as described above. Further, as described later, when the toner base particles are produced by the emulsion aggregation method, the form of the toner base particles can also be controlled by the addition timing of each resin.

  The form (the cross-sectional structure of the core-shell structure and the position of the crystalline polyester resin) of the toner base particles described above may be obtained using, for example, a known means such as transmission electron microscope (TEM) or scanning probe microscope (SPM). It is possible to confirm.

<Average Roundness of Toner Base Particles>
From the viewpoint of improving low-temperature fixability, the average circularity of the toner base particles is preferably in the range of 0.92 to 1.000, and more preferably in the range of 0.940 to 0.995. .
Here, the said average circularity is the value measured using "FPIA-2100" (made by Sysmex). Specifically, the toner base particles are wetted with a surfactant aqueous solution, subjected to ultrasonic dispersion for 1 minute, dispersed, and then HPF under the measurement condition HPF (high magnification imaging) mode using “FPIA-2100”. The number of detections is measured at an appropriate concentration of 4000. The roundness is calculated by the following equation.
Circularity = (perimeter of a circle with the same projected area as the particle image) / (perimeter of particle projection)
The mean circularity is an arithmetic mean value obtained by adding the circularity of each particle and dividing by the total number of particles measured.

«Particle diameter of toner base particle»
With regard to the particle diameter of the toner base particles, it is preferable that the volume-based median diameter (D50) be 3 to 10 μm. By setting the volume-based median diameter to the above range, reproducibility of fine lines and high image quality of a photographic image can be achieved, and the amount of consumed toner can be reduced as compared with the case where large particle size toner is used. be able to. In addition, toner fluidity can be secured. Here, the volume-based median diameter (D50) of toner base particles is measured and calculated using, for example, an apparatus in which a computer system for data processing is connected to "Coulter Multisizer 3" (manufactured by Beckman Coulter, Inc.) can do.
The volume-based median diameter of the toner base particles is controlled by the concentration of the coagulant, the amount of the solvent added in the aggregation / fusion step at the time of production of the toner described later, the fusion time, and the composition of the resin component. Can.

<External additive>
The toner of the present invention preferably contains known inorganic particles, particles such as organic particles, lubricants and the like on the surface of toner base particles as an external additive from the viewpoint of improving charging performance, fluidity, or cleaning properties.
Various external additives may be used in combination. 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, zinc titanate particles and the like. Inorganic titanic acid compound particles and the like.
Moreover, as a lubricant, salts of zinc, aluminum, copper, magnesium, calcium etc. of stearic acid, zinc of oleic acid, salts of manganese, iron, copper, magnesium etc., zinc of palmitic acid, copper, magnesium, calcium etc. And salts of higher fatty acids such as salts of zinc and calcium of linoleic acid and salts of zinc and calcium of ricinoleic acid.
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 from the viewpoint of heat resistance storage stability and environmental stability. The external additives 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 addition amount of the external additive (the total amount of two or more types used) is preferably 100% by mass, preferably 0.05 to 5% by mass, based on the total mass of the toner including the external additive. Preferably, it is in the range of 0.1 to 3% by mass.
The particle diameter of the external additive is not particularly limited, but particles such as inorganic fine particles having a number average primary particle diameter of about 2 to 800 nm and organic fine particles having a number average primary particle diameter of about 10 to 2000 nm are preferable. In the present specification, “number average primary particle diameter” refers to a value obtained by binarizing a scanning electron micrograph of external additive particles, calculating the horizontal Feret diameter for 10,000 particles, and taking the average. Say

[Method of producing toner]
The method for producing the toner according to the present invention is not particularly limited, and known methods such as a kneading and grinding method, a suspension polymerization method, an emulsion aggregation method, a dissolution suspension method, a polyester elongation method, and a dispersion polymerization method may be mentioned.
Among these, from the viewpoint of the uniformity of the particle diameter, the controllability of the shape, and the ease of formation of the core-shell structure, it is preferable to adopt the emulsion aggregation method. In addition, the emulsion aggregation method is also used from the viewpoint of easily controlling the crystalline polyester resin in the toner base particle to a desired position by utilizing the hydrophobicity of the crystalline polyester resins 1 and 2 and the release agent. It is preferred to use. Hereinafter, the emulsion aggregation method will be described.

<Emulsification aggregation method>
In the emulsion aggregation method, a dispersion of binder resin particles (hereinafter, also referred to as "binder resin particles") dispersed by a surfactant or a dispersion stabilizer, particles of a release agent (hereinafter, "mold release" (Also referred to as “agent particles”), mixed to a desired particle size, and coagulated until reaching a desired particle size, and further fusion-bonded between binder resin particles to perform shape control, thereby producing toner base particles. is there. Here, the particles of the binder resin may optionally contain a colorant, a charge control agent, and the like. A colorant may be added in the form of a dispersion of colorant particles to the dispersion of binder resin particles and the dispersion of release agent particles.
When the toner of the present invention is produced by the emulsion aggregation method, the production method according to a preferred embodiment is
(A) Step of preparing crystalline polyester resin particle dispersion, amorphous resin particle dispersion and releasing agent particle dispersion, and, if necessary, colorant particle dispersion (hereinafter also referred to as preparation step)
(B) A step of mixing, aggregating and fusing a crystalline polyester resin particle dispersion, an amorphous resin particle dispersion and a releasing agent particle dispersion, and optionally, a colorant particle dispersion (hereinafter referred to as aggregation) · Also referred to as fusion process)
including.

Hereinafter, the steps (a) to (b) and the steps (c) to (g) optionally performed other than these steps will be described in detail.
(A) Preparation Step The step (a) is a crystalline polyester resin particle dispersion preparation step, an amorphous resin particle dispersion preparation step, a release agent particle dispersion preparation step, and further, if necessary, a colorant particle dispersion Including a preparation step.
(A-1) Crystalline 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 a crystalline polyester resin constituting the binder resin. A dispersion of crystalline polyester resin particles 1 and a dispersion of crystalline polyester resin particles 2 are prepared by synthesizing crystalline polyester resins 1 and 2 and dispersing each of the crystalline polyester resins 1 and 2 in the form of fine particles in an aqueous medium. It is a process to prepare.
Since the method for producing the crystalline polyester resin is as described above, the description is omitted here.

  The crystalline polyester resin particle dispersion is prepared, for example, by a method of performing dispersion treatment in an aqueous medium without using a solvent, or dissolving the crystalline polyester resin in a solvent such as ethyl acetate or methyl ethyl ketone to form a solution, There is a method of carrying out a solvent removal treatment after the solution is used to emulsify and disperse the solution in an aqueous medium.

  In the present invention, the "aqueous medium" refers to one containing at least 50% by mass of water, and examples of components other than water include organic solvents soluble in water, such as methanol, ethanol, Isopropanol, acetone, dimethylformamide, methyl cellosolve, tetrahydrofuran and the like can be mentioned. Among these, it is preferable to use an alcohol-based organic solvent such as methanol, ethanol or isopropanol which is an organic solvent which does 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, the carboxy group is dissociated into ions, and ammonia, sodium hydroxide, etc. are added to stably emulsify in the aqueous phase to promote emulsification smoothly. Good. Furthermore, in the aqueous medium, a dispersion stabilizer may be dissolved, and a surfactant, resin particles, etc. may be added for the purpose of improving the dispersion stability of oil droplets.

  As the dispersion stabilizer, known ones can be used. For example, it is preferable to use ones that are soluble in acid or alkali such as tricalcium phosphate, or from the viewpoint of environmental aspect, by enzymes It is preferable to use a degradable one. As the surfactant, known anionic surfactants, cationic surfactants, nonionic surfactants and amphoteric surfactants can be used. Moreover, as resin particles for the improvement of dispersion stability, polymethyl methacrylate resin particles, polystyrene resin particles, polystyrene-acrylonitrile resin particles, etc. may be mentioned.

Such dispersion processing can be carried out using mechanical energy, and the dispersion machine is not particularly limited, and a homogenizer, a low speed shear type disperser, a high speed shear type disperser, a friction type dispersion, etc. Machine, high pressure jet type disperser, ultrasonic disperser, high pressure impact type disperser Altimizer, emulsification disperser, etc.
At the time of dispersion, it is preferable to heat the solution. Although heating conditions are not specifically limited, Usually, it is about 60-200 degreeC.

  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.

  In addition, 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, and 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, a vinyl resin is suitably used as the amorphous resin, and therefore, a method for preparing a vinyl resin particle dispersion (preparation step) will be described below.
In the process of preparing the vinyl resin particle dispersion, an aqueous dispersion of vinyl resin is prepared. For example, when 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.
Alternatively, the isolated vinyl resin may be pulverized if necessary, and then the vinyl resin may be dispersed in an aqueous medium using an ultrasonic dispersion machine or the like in the presence of a surfactant. The examples of the aqueous medium and the surfactant are the same as in the above (a-1), and thus the description thereof is 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 and the like.

  The content of the vinyl resin particles in the vinyl resin particle dispersion is preferably in the range of 10 to 50% by mass, and 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) Releasing Agent Particle Dispersion Preparation Step The releasing agent particle dispersion preparation step is a step of dispersing a releasing agent in the form of fine particles in an aqueous medium to prepare a dispersion of releasing agent particles. .
The said aqueous medium is as having demonstrated by said (a-1), In this aqueous medium, surfactant, a resin particle, etc. may be added in order to improve dispersion stability.
Dispersion of the release agent can be carried out using mechanical energy, and such a disperser is not particularly limited, and those described in the above (a-1) 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 is preferably in the range of 5 to 45% by mass, and more preferably in the range of 8 to 30% by mass, based on the whole dispersion. . Within such a range, the effects of preventing hot offset and securing separability can be obtained.

(A-4) Colorant Particle Dispersion Preparation Step The colorant particle dispersion preparation step is a step of preparing a dispersion of colorant particles by dispersing the colorant in the form of fine particles in an aqueous medium.
Since the said aqueous medium is as having demonstrated by said (a-1), description is abbreviate | omitted here. A surfactant, resin particles and the like may be added to the aqueous medium for the purpose of improving the dispersion stability.
Dispersion of the colorant can be carried out by a disperser using mechanical energy, and such a disperser is not particularly limited, and one described in the above (a-1) may be used. it 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, and 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 securing color reproducibility.

(B) Coagulation / fusion step This aggregation / fusion step comprises the above-mentioned crystalline polyester resin particles 1 and 2 in the aqueous medium, the non-crystalline resin particles and the releasing agent particles, and, if necessary, the colorant It is a process of aggregating particles and causing them to fuse simultaneously.

  In this step, first, the dispersion of crystalline polyester resin particles 1, the dispersion of crystalline polyester resin particles 2, the dispersion of amorphous resin particles, the dispersion of release agent particles, and, optionally, the colorant particles are dispersed. The liquids are mixed and the particles are dispersed in an aqueous medium. In the case of producing a clear toner, the aggregation and fusion steps are carried out without adding the colorant particle dispersion.

  Next, after adding an aggregating agent, heating is performed at a temperature above the glass transition temperature of the non-crystalline resin particles to advance aggregation, and at the same time, the resin particles are fused.

The coagulant is not particularly limited, but preferably selected from metal salts such as alkali metal salts and salts of Group 2 metals. 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 metal salts 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 with a smaller amount. These coagulants may be used alone or in combination of two or more.
The amount of the aggregating agent used is not particularly limited, but is preferably in the range of 0.1 to 20 parts by mass, more preferably 100 parts by mass of the solid content of the binder resin constituting the toner base particles. It is in the range of 1-15 mass parts.

In the aggregation step, it is preferable to quickly raise the temperature by heating after adding the coagulant, and the temperature rising rate is preferably set to 0.05 ° C./min or more. The upper limit of the temperature raising 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 progress of rapid fusion.
Furthermore, after the aggregation dispersion liquid reaches a desired temperature, the temperature of the aggregation dispersion liquid is maintained for a certain period of time, preferably until the volume-based median diameter becomes 4.5 to 7.0 μm, It is important to keep the

(C) Aging step This step is carried out as required, and in the aging step, the association particles obtained by the aggregation / fusion step are aged by thermal energy until they become a desired shape. Aging treatment is performed to form toner base particles.
Specifically, the aging process is performed by heating and stirring the system in which the associated particles are dispersed, and adjusting the heating temperature, the stirring speed, the heating time, and the like until the shape of the associated particles reaches a desired degree of circularity. It will be.

(D) Cooling Step This step is a step of cooling the dispersion of toner base particles. As a condition of the cooling process, 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 a method of introducing a refrigerant from the outside of the reaction vessel for cooling, a method of directly injecting cold water into a reaction system, and the like may be exemplified. it can.

(E) Filtration and Washing Step In this step, the toner base particles are separated from the cooled dispersion of the toner base particles by solid-liquid separation, and the toner cake obtained by solid-liquid separation (the toner base particles in the wet state are caked Is a step of removing deposits such as surfactants and flocculants from the aggregate (aggregated in the form of particles) and washing.
The solid-liquid separation is not particularly limited, and a centrifugal separation method, a vacuum filtration method using Nutsche, etc., a filtration method using a filter press, etc. can be used.

(F) Drying Step This step is a step of drying the washed toner cake, and can be carried out in accordance with the drying step in the generally known production method of toner base particles.
Specifically, as a dryer used for drying the toner cake, a spray dryer, a vacuum freeze dryer, a vacuum dryer, etc. can be mentioned, and a stationary shelf dryer, a movable shelf dryer, a fluidized bed, etc. It is preferable to use a drier, a rotary drier, a stirring drier or the like.

(G) Additive Step of External Additive This step is a step which is performed as necessary when adding the external additive to the toner base particles.
As a mixing apparatus of an external additive, mechanical mixing apparatus, such as a Henschel mixer, a coffee mill, and a sample mill, can be used.

<Developer>
The toner of the present invention can be used as a magnetic or nonmagnetic 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, magnetic particles made of conventionally known materials such as metals such as iron, ferrite and magnetite and alloys of these metals and metals such as aluminum and lead are used as the carrier. Ferrite particles can be used, in particular. Further, as the carrier, a coated carrier in which the surface of the magnetic particles is coated with a coating agent such as a resin, or a dispersion type carrier obtained by dispersing magnetic powder 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 measured typically by a laser diffraction type particle size distribution measuring apparatus "HELOS" (manufactured by Sympathic) equipped with a wet disperser.
The two-component developer can be produced by mixing the above-described carrier and toner using a mixing device. As a mixing apparatus, a Henschel mixer, a Nauta mixer, V-type mixer etc. are mentioned, for example.
It is preferable that the compounding amount of the toner at the time of producing the two-component developer is in the range of 1 to 10% by mass with respect to 100% by mass of the total of the carrier and the toner.

[Image formation method]
An 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 a full-color image forming method, four color developing devices for yellow, magenta, cyan and black, and one electrostatic latent image carrier (also referred to as "electrophotographic photosensitive member" or simply "photosensitive member") A method using an image forming apparatus of a 4-cycle system, and a tandem type image forming apparatus in which an image forming unit having a color developing device for each color and an electrostatic latent image carrier is separately installed. Any image forming method such as a method to be used can be used.
When clear toner is further used, five types of developing devices for yellow, magenta, cyan, black and clear, and one electrostatic latent image carrier ("electrophotographic photosensitive member" or simply "photosensitive A method using an image forming apparatus of the 5-cycle method, which is also composed of “body”, and an image forming unit having a developing device for each color including clear toner and an electrostatic latent image carrier, separately for each color An image forming method such as a method using a tandem type image forming apparatus can be used.

Preferred examples of the image forming method include an image forming method including a fixing step by a heat and pressure fixing method capable of applying and heating pressure.
In this image forming method, specifically, for example, an electrostatic latent image formed on a photosensitive member is developed using the above toner to obtain a toner image, and this toner image is used as an image support After the transfer, the toner image transferred onto the image support is fixed to the image support by a fixing process using a heat and pressure fixing method, whereby a printed matter on which a visible image is formed can be obtained.
The application of pressure and the heating in the fixing step are preferably simultaneous, 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 heat and pressure fixing type image forming method. As the fixing device of the heat and pressure fixing method used for the image forming method according to the present invention, various known ones can be adopted. Hereinafter, a heat roller type fixing device and a belt heating type fixing device will be described as the heat pressure fixing device.

(I) Heat Roller Type Fixing Device The heat roller type fixing device generally has a roller pair 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, whereby a so-called fixing nip portion is formed in this deformed portion.
In general, the heating roller is formed by arranging a heat source such as a halogen lamp inside a metal core made of a hollow metal roller made of aluminum or the like. The heat roller heats the cored bar by the heat source. At this time, energization of the heat source is controlled to control the temperature so that the outer peripheral surface of the heating roller is maintained at a predetermined fixing temperature.
The fixing device has a capability of sufficiently heating and melting 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, when the fixing device includes a cored bar having a high heat capacity as a heating roller, and includes an elastic layer for uniformly melting the toner image formed on the outer peripheral surface of the cored core. preferable.

Also, the pressure roller has an elastic layer made of soft rubber such as urethane rubber and silicone rubber.
As a pressure roller, a cored bar made of a hollow metal roller made of aluminum or the like may be used, and one having an elastic layer formed on the outer peripheral surface of the cored bar may be used.
Furthermore, when the pressure roller has a core metal, a heat source such as a halogen lamp may be disposed inside the core metal in the same manner as the heating roller. Then, the heat source may be used to heat the cored bar, and the temperature control may be performed by controlling the energization of the heat source such that the outer peripheral surface of the pressure roller is maintained at a predetermined fixing temperature.
The outermost layers of these heating rollers and pressure rollers are, for example, release layers made of a fluororesin such as polytetrafluoroethylene (PTFE) or tetrafluoroethylene-perfluoroalkylvinylether copolymer (PFA). It is preferable to use what is formed.
In such a heat roller type fixing device, heating by the heating roller and pressure at the fixing nip portion are carried out by rotating the roller pair to nip and convey the image support to form a visible image in the fixing nip portion. And the unfixed toner image is fixed to the image support.

  In the image forming method according to the present invention, the low temperature fixability is also good. Therefore, in the fixing device of the heat roller system, the temperature of the heating roller can be made relatively low, and specifically, it can be made 150 ° C. or less. Furthermore, the temperature of the heating roller is preferably 140 ° C. or less, more preferably 135 ° C. or less. From the viewpoint of excellent low temperature fixability, the temperature of the heating roller is preferably as low as possible, and the lower limit thereof is not particularly limited, but is substantially about 90 ° C.

(Ii) Belt Heating Type Fixing Device Generally, a belt heating type fixing device is composed of a heating body made of, for example, a ceramic heater, a pressure roller, and a heat resistant belt between the heating body and the pressure roller. A fixing belt is sandwiched, and a so-called fixing nip portion is formed in this deformed portion by the pressure roller being deformed by the pressure applied between the heating body and the pressure roller. It is.

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

In such a belt heating type fixing device, an image support carrying an unfixed toner image is nipped 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 member through the fixing belt and application of pressure in the fixing nip portion are performed, and the unfixed toner image is fixed to the image support.
According to such a fixing device of the belt heating system, the heating member may be 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 the powering on of the image forming apparatus to the state where the image forming can be performed. In addition, the power consumption at the time of standby of the image forming apparatus is extremely small, and power saving can be achieved.

As described above, the heating body, the pressure roller, and the fixing belt, which are used as the fixing member in the fixing step, preferably have a plurality of layer configurations.
In the fixing device of the belt heating type, the temperature of the heating body can be relatively lowered, and specifically, can be 150 ° C. or less. Furthermore, the temperature of the heating body is preferably 140 ° C. or less, more preferably 135 ° C. or less. From the viewpoint of excellent low temperature fixability, the temperature of the heating member is preferably as low as possible, and the lower limit thereof is not particularly limited, but is substantially about 90 ° C.

(recoding media)
A recording medium (also referred to as recording material, recording paper, recording paper, etc.) may be a commonly used one, for example, as long as it holds a toner image formed by a known image forming method using an image forming apparatus etc. It is not particularly limited. Usable image supports include, for example, plain paper from thin paper to heavy paper, high quality paper, art paper, coated printing paper such as coated paper, commercially available washi paper or postcard paper, OHP Plastic films, cloths, various resin materials used for so-called soft packaging, or resin films formed by molding them into a film, labels and the like.
As mentioned above, although embodiment of this invention was described, this invention is not limited to said form, A various change can be added.

  EXAMPLES Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto. In addition, in an Example, the display of "part" or "%" represents "mass part" or "mass%" unless there is particular notice.

[Analysis conditions]
<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 Perkin Elmer). First, 3.0 mg of a measurement sample (resin) was enclosed in an aluminum pan, and set in a sample holder of “diamond DSC”. The reference used an empty aluminum pan. Then, a first heating process of raising the temperature from 0 ° C. to 200 ° C. at a heating rate of 10 ° C./min, a cooling process of cooling 200 ° C. to 0 ° C. at a cooling rate of 10 ° C./min, and a heating rate of 10 ° C./minute. A DSC curve was obtained under the measurement conditions (temperature raising / cooling conditions) which sequentially passes through a second temperature raising process in which the temperature is raised from 0 ° C. to 200 ° C. in a minute. Based on the DSC curve obtained by this measurement, the extension of the baseline before the rising of the first endothermic peak in the second temperature rising process and the maximum between the rising portion of the first peak and the peak apex The tangent which shows inclination was drawn and the intersection was made into glass transition temperature (Tg).
Further, the melting point of the crystalline polyester resin is an endothermic peak derived from the crystalline resin in the second temperature rising process (an endothermic peak whose half width is within 15 ° C.) based on the DSC curve obtained in the same manner as described above. The temperature at the peak top of) was taken 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) by GPC of each resin was measured as follows.
That is, using the apparatus “HLC-8120GPC” (made by Tosoh Corp.) and the column “TSKguardcolumn + TSKgelSuperHZ-M3 series” (made by Tosoh Corp.), while maintaining the column temperature at 40 ° C. It flowed at 0.2 mL / min. The measurement sample (resin) was dissolved in tetrahydrofuran to a concentration of 1 mg / ml. The preparation of the solution was carried out by treating for 5 minutes at room temperature using an ultrasonic disperser. Then, the sample solution was treated with a membrane filter with a pore size of 0.2 μm to obtain a sample solution, and 10 μL of this sample solution was injected into the device 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 a calibration curve prepared using monodispersed polystyrene standard particles. Ten points were used as polystyrene for the above 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 introducing pipe, a dewatering pipe, a stirrer and a thermocouple, 0.8 parts by mass of Ti (n-OBu) ₄ as a raw material monomer of the following polycondensation resin and an esterification catalyst are put The reaction was allowed to proceed for 4 hours.
-250 parts by mass of 1, 6-hexanediol 250 parts by mass of 1, 14-tetradecanedioic acid Then, the temperature is raised to 210 ° C at 10 ° C / h and maintained at 210 ° C for 5 hours, and then under reduced pressure (8 kPa) A crystalline polyester resin [A1] was obtained by reacting for 1 hour. The obtained crystalline polyester resin [A1] had a number average molecular weight (Mn) of 4500 and a melting point of 81 ° C.

<Preparation of Crystalline Polyester Resin Particle Dispersion [a1]>
Thirty parts by mass of the crystalline polyester resin [A1] was melted and transferred in a molten state at a transfer speed of 100 parts by weight per minute to the emulsifying and dispersing machine “Cavitron CD1010” (manufactured by Eurotech Co., Ltd.). At the same time as the transfer of the crystalline polyester resin [A1] in the molten state, dilute ammonia water with a concentration of 0.37% by mass (70 parts by mass of reagent ammonia water in the aqueous solvent tank is ion-exchanged) Diluted with water) was transferred at a transfer rate of 0.1 L / min while heating to 100 ° C. with a heat exchanger. Then, the emulsifying and dispersing machine is operated at a rotational speed of a rotor of 60 Hz and a pressure of 5 kg / cm ² , and thereafter ion-exchanged water is added to adjust the solid content to be 20 mass%, and the volume based median A dispersion [a1] containing crystalline polyester resin [A1] particles having a diameter of 200 nm was prepared.

<Preparation of Crystalline Polyester Resin Particle Dispersion [Dispersion a2] to [Dispersion a10]>
Crystalline polyester resins [A2] to [A10] were obtained in the same manner as in the synthesis of the crystalline polyester resin [A1] except that the raw material monomers were changed as shown in Table II below.
Furthermore, in the preparation of the crystalline polyester resin particle dispersion [a1], crystalline polyester resin particles are similarly prepared except that the crystalline polyester resin [A1] is changed to the crystalline polyester resins [A2] to [A10]. 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-liter reaction vessel equipped with an agitator, a temperature sensor, a condenser and a nitrogen introducing device, and agitation is performed at a stirring speed of 230 rpm under a nitrogen stream. While raising the internal temperature to 80.degree.
Then, a solution in which 15.0 parts by mass of potassium persulfate (KPS) was dissolved in 300 parts by mass of ion exchange water was added, and the solution temperature was adjusted to 80 ° C. Furthermore, a monomer mixture comprising 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 dripped over 2 hours. After completion of the dropwise addition, polymerization was carried out by heating and stirring at 80 ° C. for 2 hours to prepare a dispersion [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 Corporation)
200 parts by mass · 1600 parts by mass of ion-exchanged water The solution obtained by mixing the above components is sufficiently dispersed with UltraTarax T50 (manufactured by IKA), and then treated with an ultrasonic dispersion machine for 20 minutes to obtain black colorant particles A dispersion [Bk] was prepared. With respect to the obtained black colorant particle dispersion [Bk], the volume-based median diameter of the colorant particles was 110 nm.

Preparation of Yellow Colorant Particle Dispersion [Ye]
-90 parts by mass of sodium dodecyl sulfate-C.I. I. Pigment yellow 74 200 parts by mass · Ion exchange water 1600 parts by mass After a solution obtained by mixing the above components is sufficiently dispersed with UltraTarax T50 (manufactured by IKA Co., Ltd.), yellow is processed by an ultrasonic dispersion machine for 20 minutes. A colorant particle dispersion [Ye] was prepared. The volume-based median diameter of the colorant particles in the obtained yellow colorant particle dispersion [Ye] was 240 nm.

Preparation of Magenta Colorant Particle Dispersion [Ma]
-90 parts by mass of sodium dodecyl sulfate-C.I. I. Pigment Red 269 200 parts by mass · Ion exchange water 1600 parts by mass After a solution obtained by mixing the above components is sufficiently dispersed with UltraTarax T50 (manufactured by IKA Corporation), the treatment with an ultrasonic dispersion machine is performed for 20 minutes. A colorant particle dispersion [Ma] was prepared.
The volume-based median diameter of the colorant particles of the obtained magenta colorant particle dispersion [Ma] was 200 nm.

Preparation of Cyan Colorant Particle Dispersion [Cy]
-90 parts by mass of sodium dodecyl sulfate-C.I. I. Pigment Blue 15: 3 200 parts by mass · Ion exchange water 1600 parts by mass After a solution obtained by mixing the above components is sufficiently dispersed with UltraTarax T50 (manufactured by IKA), treated with an ultrasonic dispersion machine for 20 minutes A cyan colorant particle dispersion [Cy] was prepared by The volume-based median diameter of the colorant particles in the obtained cyan colorant particle dispersion [Cy] was 180 nm.

Preparation of Releasing Agent Particle Dispersion [W1]
-Paraffin wax (HNP0190, manufactured by Nippon Seiwa Co., Ltd. (melting point: 85 ° C))
200 parts by mass Sodium dodecyl sulfate 20 parts by mass Ion exchanged water 1800 parts by mass The above materials were mixed, heated to 95 ° C., and sufficiently dispersed with ITRA UltraTalux T50. Thereafter, dispersion treatment was performed with a pressure discharge type Gorin homogenizer to prepare a release agent particle dispersion [W1]. The volume-based median diameter of the release agent particles in this dispersion was 110 nm.

[Preparation of black toner [Bk1]]
(Aggregation / fusion process and aging process)
A crystalline polyester resin particle dispersion [a1] 38.4 parts by mass (solid content conversion: 7.7 parts by mass) and a crystalline polyester resin particle dispersion [a5] in a reaction vessel equipped with a stirrer, a temperature sensor, and a cooling pipe. 89.6 parts by mass (solids conversion 17.97 parts by mass), styrene / acrylic resin particle dispersion [b1] 268.8 parts by mass (solids conversion 80.6 parts by mass), colorant particle dispersion [Bk ] After 51.9 mass parts (solid content conversion 5.8 mass parts) and release agent particle dispersion liquid [W1] 76.8 mass parts (solid content conversion 7.7 mass parts) are added, 5 mol / L The pH (25 ° C.) was adjusted to 10 by addition of aqueous sodium hydroxide solution.
Then, an aqueous solution in which 12 parts by mass of magnesium chloride was dissolved in 12 parts by mass of ion exchange water was added over 10 minutes at 30 ° C. with stirring. The temperature is raised, this system is heated to 80 ° C. over 60 minutes, and the particle diameter of the associated particles is measured with “Coulter Multisizer 3” (manufactured by Beckman Coulter Co.), and the median diameter on a volume basis is The stirring speed was controlled to be 6.0 μm. Thereafter, an aqueous solution in which 45 parts by mass of sodium chloride was dissolved in 180 parts by mass of ion exchange water was added to stop particle growth. The particles were further fused by heating and stirring at 80 ° C.

(Cooling process)
After that, using a measuring device "FPIA-3000" (manufactured by Sysmex) of the average circularity of toner mother particles (the number of detected HPF: 4000), the average circularity becomes 0.957 when the average circularity reaches 0.957. It cooled to 30 degreeC by the cooling rate.

(Filtration, washing process and drying process)
Next, after repeating the solid-liquid separation and dewatering toner cake re-dispersion in ion-exchange water and solid-liquid separation three times, the black toner base particles [XBk1] are dried at 40 ° C. for 24 hours. I got

(Addition process of external additive)
0.6 parts by mass of hydrophobic silica (number average primary particle diameter = 12 nm, degree of hydrophobization = 68) and hydrophobic titanium oxide (number average primary particle diameter = 20 nm) in 100 parts by mass of the obtained toner base particles [XBk1] , Hydrophobicity = 63) 1.0 part by mass added, and after external additive treatment step of mixing at 32 ° C for 20 minutes at a rotor peripheral speed of 35 m / sec with "Henshell mixer" (made by Mitsui Miike Kako Co., Ltd.) By removing coarse particles using a 45 μm sieve, black toner [Bk1] was obtained.

(Developer preparation process)
To a black toner [Bk1], the toner concentration becomes 6 mass% using a ferrite carrier with a volume average particle diameter of 30 μm coated with a copolymer resin (monomer mass ratio = 1: 1) of cyclohexyl methacrylate and methyl methacrylate By mixing as described above, a black developer [Bk1] was obtained.

[Preparation of Black Developer [Bk2] to [Bk12]]
In the preparation of the black developer [Bk1], a black developer [Bk2] is prepared in the same manner as described above except that the type and amount of the dispersion (resin) used are changed as shown in Table III below. To [Bk12] were produced respectively.

  In Table III, whether 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) , ○ or ×.

[Preparation of Yellow Developer [Ye1] to [Ye12]]
In the preparation of the black developer [Bk1], except that the type and amount of the dispersion (resin) used and the type and amount of the coloring agent were changed as shown in Table IV below, respectively. Similarly, yellow developers [Ye1] to [Ye12] were prepared.

[Preparation of Magenta Developer [Ma1] to [Ma12]]
In the preparation of the black developer [Bk1], except that the type and amount of the dispersion (resin) used and the type and amount of the coloring agent were changed as shown in Table V below, respectively, Similarly, magenta developers [Ma1] to [Ma12] were prepared.

[Preparation of cyan developers [Cy1] to [Cy12]]
In the preparation of the black developer [Bk1], except that the type and amount of the dispersion (resin) used and the type and amount of the coloring agent were changed as shown in Table VI below, respectively, Similarly, cyan developers [Cy1] to [Cy12] were produced respectively.

[Evaluation]
<Low temperature fixability>
The fixing device of the copying machine "bizhub PRESS (registered trademark) C 1070" (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 copying machine according to the combination of developers shown in the following Table VII and evaluated.
First, black toner, yellow toner, magenta toner and cyan toner on high quality paper "CF paper" (Konica Minolta Co., Ltd.) of A4 size under the environment of normal temperature and normal humidity (temperature 20 ° C., humidity 50% RH) The adhesion amount of the superimposed image was set to be 10.0 g / m ² . At this time, the adhesion amounts of the black toner, the yellow toner, the magenta toner and the cyan toner were set so as not to differ. Thereafter, a fixing experiment for fixing a 100 mm × 100 mm size four-color image was repeatedly performed up to 180 ° C. while changing the set fixing temperature from 120 ° C. to increase in 1 ° C. increments.
The printed matter at each fixing temperature obtained above was visually confirmed, and the lowest temperature at which all the toners were fixed to the paper without fixing to the fixing roller was regarded as the lowest fixing temperature (° C.) and ranked as follows.
-Evaluation criteria-
○: less than 140 ° C. Δ: 140 ° C. or more and less than 150 ° C. x: 150 ° C. or more ○ and Δ are accepted levels.

<Heat-resistant storage stability of toner>
For each of the prepared toners, 0.5 g of each toner is put into a 10 mL glass bottle with an inner diameter of 21 mm, the lid is closed, and shaking is performed 600 times at room temperature using a shaker "Tapdenser KYT-2000" (manufactured by Seishin Enterprise Co., Ltd.) did. After that, it was left for 2 hours in an environment of a temperature of 55 ° C. and a humidity of 35% RH with the lid opened.
Next, place the toner on a 48-mesh (350 μm mesh) screen, taking care not to crush the toner aggregates, set it in the “Powder Tester” (manufactured by Hosokawa Micron Corporation), and use the presser bar and knob nut Fixed. The vibration intensity was adjusted to a feed width of 1 mm, vibration was applied for 10 seconds, and then 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 ratio (%) = (mass of toner remaining on sieve (g)) / 0.5 (g) × 100)
Similar measurements are taken at temperatures of 57.5 ° C. and 60 ° C., respectively, with the X-axis plotted as temperature and the Y-axis plotted as toner aggregation. Of the temperatures 55 ° C., 57.5 ° C. and 60 ° C., an approximate straight line is drawn between 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 interpolation. . The temperature at that time is taken as the heat resistant temperature. The rank was evaluated as follows.
-Evaluation criteria-
○: 58 ° C. or more Δ: 57 ° C. or more and less than 58 ° C. x: less than 57 ° C.

<Mother Fluidity of Toner>
After placing 20.0 g of toner before image evaluation on a 120 mesh sieve and dropping the toner for 60 seconds with vibration intensity 6, measure the amount of toner remaining on the sieve and measure the toner sieve according to the following formula (B) The passing rate was calculated and ranked as follows.
Formula (B): Toner sieve passing ratio (%) = (passing toner mass on sieve (g)) / 20.0 (g) × 100)
-Evaluation criteria-
○: 60% or more Δ: 50% or more and less than 60% ×: less than 50%
○ and を are the pass level.

  From the above results, when the toner of the present invention is used, it is recognized that the toner of the present invention is superior in low temperature fixability, heat resistant storage stability and fluidity to the toner of the comparative example.

Claims (7)

A toner for developing an electrostatic charge image containing at least toner base particles;
The toner base particles contain an amorphous resin, a releasing 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 (C1 (alcohol)) of the polyhydric alcohol component of the crystalline resin 1, the carbon number (C2 (alcohol)) of the polyhydric alcohol component of the crystalline resin 2, and the polyvalent of the crystalline resin 1 The carbon number (C1 (acid)) of the carboxylic acid component and the carbon number (C2 (acid)) of the polyvalent carboxylic acid component of the crystalline resin 2 satisfy the relationship of the following formulas (1) to (4) A toner for developing an electrostatic charge image characterized by
C1 (acid)> C1 (alcohol) formula (1)
C2 (acid)> C2 (alcohol) formula (2)
C1 (alcohol) ≠ C2 (alcohol) formula (3)
C1 (acid) = C2 (acid) Formula (4)   The electrostatic 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 non-crystalline 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 a relationship of the following formula (5) The toner for developing an electrostatic charge image according to claim 1 or 2, wherein the toner is filled.
| C 1 (alcohol) -C 2 (alcohol) | ≧ 2 Formula (5) 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 represented by the following formula (6) The toner for developing an electrostatic charge image according to any one of claims 1 to 3, which satisfies the relationship of (7).
C1 (acid) 10 10 ... Formula (6)
C2 (acid) 10 10 ... Formula (7) At least the carbon number (C1 (alcohol)) of the crystalline resin 1 and the carbon number (C2 (alcohol)) of the polyhydric alcohol component of the crystalline resin 2 satisfy the following formula (8), and the mass ratio thereof The electrostatic charge image according to any one of claims 1 to 4, wherein the value of (Crystalline resin 1 / Crystalline resin 2) is in the range of 60/40 to 1/99. Developing toner.
C1 (alcohol)> C2 (alcohol) formula (8)   The toner according to any one of claims 1 to 5, wherein the toner base particles have a core-shell structure.   The toner for electrostatic image development according to any one of claims 1 to 6, wherein the amorphous resin contains a styrene-acrylic resin.