JP2009237098A - Toner for electrostatic charge image development, electrostatic charge image developer, toner cartridge, process cartridge, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner for electrostatic charge image development, which suppresses gloss unevenness and a mark of a releasing member in a fixed image and can be fixed at a low temperature, and also to provide an electrostatic charge image developer containing the above toner for electrostatic charge image development, a toner cartridge, a process cartridge and an image forming apparatus. <P>SOLUTION: The toner shows an absolute difference ΔTm between a melting point Tmc (°C) of a crystalline resin and a melting point Tmw (°C) of a release agent ranging from 10 (°C) to 30 (°C). In a differential scanning calorimetry of the toner, a heat absorption amount at an endothermic peak in a lower temperature side and a heat absorption amount at an endothermic peak in a higher temperature side in the first temperature rising stage of the measurement are denoted as ΔHl1 and ΔHh1, respectively, and a heat absorption amount at an endothermic peak in the lower temperature side and a heat absorption amount at an endothermic peak in the higher temperature side in the second temperature rising stage are denoted as ΔHl2 and ΔHh2, respectively, and the toner satisfies the relationship expressed by formula (1):0.15<ΔHl2/ΔHl1<0.45 and formula (2):0.75<ΔHh2/ΔHh1<0.95. The toner is used for the electrostatic charge image developer, the toner cartridge, the process cartridge and the image forming apparatus. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrostatic charge image developing toner, an electrostatic charge image developer, a toner cartridge, a process cartridge, and an image forming apparatus.

  Conventionally, as a fixing method of an electrostatic charge image developing toner (hereinafter sometimes simply referred to as “toner”), a pressure fixing method using only a pressure roll at room temperature, a contact heating fixing method using a heating roll, etc., or an oven Non-contact fixing methods such as oven fixing method by heating, flash fixing method by xenon lamp etc., electromagnetic wave fixing method by microwave etc., solvent fixing method using solvent vapor, etc. are mentioned, but oven fixing method using heat or contact heating The mold fixing method is mainly used from the viewpoint of reliability and safety.

  In particular, the contact heating type fixing method using a heating roll, a belt, or the like is usually composed of a heating roll or belt provided with a heating source and a pressure roll or belt, and a toner image surface of a recording medium on the heating roll or belt surface. Fixing is performed by allowing the toner to pass through while being in pressure contact, and since the surface of the heated roll or belt and the toner image surface of the recording medium are in direct contact, the heat efficiency is effective and the fixing can be performed quickly. Has been widely adopted.

On the other hand, it is known that a polycondensation toner contains a crystalline resin in order to achieve both energy saving, environmental load and high image quality. For example, an image forming method in which toner containing a crystalline resin is used and heated at a temperature equal to or higher than the melting point of the crystalline resin has been proposed (for example, see Patent Document 1). In addition, a toner has been proposed in which the relationship between the endothermic amounts based on the endothermic peaks in the first temperature raising process and the second temperature raising process in differential scanning calorimetry (see, for example, Patent Document 2). Further, a toner is proposed in which the relationship between the temperature that is half the low temperature side of the melting point peak height of the toner, the heating temperature of the aggregated particles, and the melting point of the toner in differential scanning calorimetry (for example, patents). (Ref. 3)
JP 2006-3390 A JP 2006-251564 A JP 2006-267331 A

  When the polycondensation toner generally contains a crystalline resin, it is difficult to control the degree of compatibility in the binder resin and the degree of compatibility of the release agent. Separation tendency tends to be prominent. As a result, the low-temperature fixability is impaired, and in the case of extreme separation, fixed image defects (such as image gloss unevenness, release member marks, and image contact surface fixation) are likely to occur in a high-speed machine or the like. The image forming method described in Patent Document 1 is intended to suppress the occurrence of roll contact marks and to form an image with high glossiness. The toner described in Patent Document 2 reproduces a light color without graininess. For this purpose, the toner described in Patent Document 3 is intended to improve storage stability and image storage stability, and further improvements are desired.

  The present invention relates to a toner for developing an electrostatic image capable of suppressing low-temperature gloss unevenness and a release member mark in a fixed image and capable of fixing at a low temperature, an electrostatic image developer containing the toner for developing an electrostatic image, and the electrostatic image development It is an object of the present invention to provide a toner cartridge containing a toner for use, a process cartridge using the electrostatic charge image developer, and an image forming apparatus. The release member mark here means that when the fixing temperature of the low-temperature fixing toner is high, an image on the image support discharged from the fixing machine is not sufficiently cooled, and the peeling member (roll shape, nail) in the fixing machine is used. Or the like) that cause scratches on the fixed image.

The above-mentioned subject is achieved by the following present invention. That is,
The invention according to claim 1
Containing a crystalline resin and a release agent,
The absolute value ΔTm of the difference between the melting point Tmc (° C.) of the crystalline resin and the melting point Tmw (° C.) of the release agent is 10 (° C.) or more and 30 (° C.) or less,
In the differential scanning calorimetry according to ASTM D3418-8, the endothermic amount based on the endothermic peak on the low temperature side in the first temperature rising process is ΔHl1, the endothermic amount based on the endothermic peak on the high temperature side is ΔHh1, and the second temperature rising. In the process, when the endothermic amount based on the endothermic peak on the low temperature side is ΔHl2, and the endothermic amount based on the endothermic peak on the high temperature side is ΔHh2, the relationship of the following formulas (1) and (2) is satisfied. This is a toner for developing an electrostatic image.
0.15 <ΔHl2 / ΔHl1 <0.45 (1)
0.75 <ΔHh2 / ΔHh1 <0.95 (2)

The invention according to claim 2
2. The electrostatic image developing toner according to claim 1, wherein an inorganic abrasive and an inorganic additive having an average primary particle diameter of 50 nm to 100 nm are externally added.

The invention according to claim 3
An electrostatic image developer comprising: a toner, wherein the toner is the electrostatic image developing toner according to claim 1.

The invention according to claim 4
A toner cartridge comprising at least a toner, wherein the toner is the electrostatic image developing toner according to claim 1.

The invention according to claim 5
A process cartridge comprising at least a developer holder and containing the electrostatic image developer according to claim 3.

The invention according to claim 6
A latent image holding member, developing means for developing the electrostatic image formed on the latent image holding member as a toner image with a developer, and transferring the toner image formed on the latent image holding member onto the transfer target An image forming apparatus comprising: a transfer unit configured to transfer image data; and a fixing unit configured to fix a toner image transferred onto a transfer target, wherein the developer is the electrostatic charge image developer according to claim 3. Device.

The invention according to claim 7 provides:
The image forming apparatus according to claim 6, wherein a process speed is 350 mm / s or more.

According to the first aspect of the present invention, it is possible to provide a toner for developing an electrostatic image that can suppress gloss unevenness and a release member mark in a fixed image and can be fixed at a low temperature.
According to the second aspect of the present invention, the uniformity of the release agent exposed to the image surface is further improved while maintaining the toner storability, and the storage stability is improved, whereby image defects are further suppressed.

According to the third aspect of the present invention, it is possible to provide an electrostatic charge image developer capable of suppressing low-temperature unevenness and release member marks in a fixed image and fixing at a low temperature.
According to the fourth aspect of the present invention, it is possible to provide a toner cartridge that supplies toner for developing an electrostatic charge image capable of suppressing low-temperature unevenness and release member marks in a fixed image and fixing at low temperature.
According to the fifth aspect of the present invention, it is possible to provide a process cartridge that can suppress gloss unevenness and a release member mark in a fixed image and can be fixed at a low temperature.

According to the sixth aspect of the present invention, it is possible to provide an image forming apparatus that can suppress gloss unevenness and a release member mark in a fixed image and can be fixed at a low temperature.
According to the seventh aspect of the present invention, it is possible to maintain the effect that low-temperature fixing is possible by suppressing gloss unevenness and a release member mark in a fixed image even in high-speed operation.

Hereinafter, embodiments of the present invention will be described in detail.
<Toner for electrostatic image development>
The electrostatic image developing toner of the present embodiment (hereinafter sometimes referred to as “the toner of the present embodiment”) contains a crystalline resin and a release agent, and has a melting point Tmc (° C.) of the crystalline resin. The absolute value ΔTm of the difference from the melting point Tmw (° C.) of the release agent is 10 (° C.) or more and 30 (° C.) or less, and the first temperature increase in differential scanning calorimetry according to ASTM D3418-8 In the process, the endothermic amount based on the endothermic peak on the low temperature side is ΔHl1, the endothermic amount based on the endothermic peak on the high temperature side is ΔHh1, and the endothermic amount based on the endothermic peak on the low temperature side in the first temperature rising process is ΔHl2. When the endothermic amount based on the side endothermic peak is ΔHh2, the relationship of the following formulas (1) and (2) is satisfied. In the differential scanning calorimetry based on ASTM D3418-8, two endothermic peaks are generated due to the crystalline resin and the release agent. In this embodiment, in the first and second temperature rising processes, Regarding the endothermic peak and the endothermic peak on the high temperature side, the relationship of the following formulas (1) and (2) was defined.
0.15 <ΔHl2 / ΔHl1 <0.45 (1)
0.75 <ΔHh2 / ΔHh1 <0.95 (2)

  The toner according to the exemplary embodiment includes a crystalline resin and a release agent, and an absolute value ΔTm of a difference between a melting point Tmc (° C.) of the crystalline resin and a melting point Tmw (° C.) of the release agent is It is 10 (° C) or more and 30 (° C) or less, preferably 15 (° C) or more and 25 (° C) or less, and more preferably 17 (° C) or more and 23 (° C) or less. When the ΔTm is less than 10 (° C.), it may be difficult to satisfy the relationship of the formulas (1) and (2). When it exceeds 30 (° C.), specifically, a release agent. If the melting point of the resin is too high, the releasability is reduced and offset is likely to occur, and if the melting point of the crystalline resin is too low, the toner becomes low in viscosity and storage stability near room temperature decreases, or the toner is in the developing machine. When the heat history is received, the fluidity may decrease.

  Further, from the viewpoint of sufficiently compatibilizing and melting at the time of melting the toner and imparting low-temperature fixability, and from the viewpoint of imparting stable and sufficient powder fluidity as a toner even near room temperature, the melting point Tmw (° C.) of the crystalline resin. ) Is preferably 55 (° C.) or higher and 90 (° C.) or lower, and more preferably 60 (° C.) or higher and 86 (° C.) or lower. Furthermore, the melting point Tmw (° C.) of the release agent is 80 (° C.) or more and 110 (° C.) or less from the viewpoint of maintaining sufficient releasability at low temperature and releasability at high temperature. Preferably, it is 85 (° C.) or more and 100 (° C.) or less.

  In the toner of this embodiment, in the differential scanning calorimetry according to ASTM D3418-8, the endothermic amount based on the endothermic peak on the low temperature side in the first temperature rising process is ΔH11, and the endothermic amount based on the endothermic peak on the high temperature side. When ΔHh1, the endothermic amount based on the endothermic peak on the low temperature side in the first temperature rising process is ΔHl2, and the endothermic amount based on the endothermic peak on the high temperature side is ΔHh2, the relationship between the above formulas (1) and (2) Meet.

When differential scanning calorimetry (DSC) was performed on this toner in accordance with ASTM D3418-8, the first temperature rising process corresponds to a thermal fixing process in an actual machine, and the second temperature rising process is an image of the image after fixing. It is thought that it corresponds to thermal stability. Further, the low temperature side component (the component having a low melting point of the crystalline resin and the release agent, the crystalline resin, and the release agent have a melting point within the above preferable range, which is required in the first and second temperature raising processes. If this is the case, the ratio ΔHl2 / ΔHl1 of the endothermic amounts ΔHl1 and ΔHl2 based on the melting peak (the low temperature side endothermic peak) of the crystalline resin is the low temperature side component before and after toner fixing. In other words, it represents the ratio at which the low temperature side component once melted by the heat energy at the time of fixing is recrystallized by cooling.
On the other hand, the high temperature side component (a component having a high melting point among the crystalline resin and the release agent, the crystalline resin, and the release agent have a melting point within the above preferred range, which is required in the first and second temperature raising processes. If this is the case, the ratio ΔHh2 / ΔHh1 of the endothermic amounts ΔHh1 and ΔHh2 based on the melting peak (high temperature side endothermic peak) of the crystalline resin becomes the low temperature side component. In other words, it represents the ratio at which the high temperature side component once melted by the heat energy at the time of fixing is recrystallized by cooling.

The ΔHl2 / ΔHl1 is greater than 0.15, preferably greater than 0.20, and more preferably greater than 0.25. When ΔHl2 / ΔHl1 is 0.15 or less, the storage property of the toner is deteriorated.
On the other hand, the ΔHl2 / ΔHl1 is smaller than 0.45, preferably smaller than 0.40, and more preferably smaller than 0.35. When ΔHl2 / ΔHl1 is 0.45 or more, the low-temperature fixability is impaired and gloss unevenness becomes remarkable.

The ΔHh2 / ΔHh1 is greater than 0.75, preferably greater than 0.80, and more preferably greater than 0.85. When the ΔHh2 / ΔHh1 is 0.75 or less, the releasability is deteriorated.
On the other hand, ΔHh2 / ΔHh1 is smaller than 0.95, preferably smaller than 0.93, and more preferably smaller than 0.90. When ΔHh2 / ΔHh1 is 0.95 or more, there is a problem that the exposure of the release component on the toner surface becomes remarkable, the crystal component exposure on the image surface becomes remarkable, and the gloss unevenness becomes remarkable. .

  The toner of the exemplary embodiment is preferably externally added with an inorganic abrasive and an inorganic additive having a primary particle size of 50 nm to 100 nm. By externally adding an inorganic abrasive and an inorganic additive having a primary particle size of 50 nm or more and 100 nm or less, the uniformity of the release agent exposed on the image surface is further improved while maintaining the toner storability and storage stability. As a result, image defects are further suppressed. Details of the inorganic abrasive and the inorganic additive having a primary particle diameter of 50 nm to 100 nm will be described later.

  The differential thermal analysis in the present embodiment, including the measurement of the endothermic amount described above, is performed by differential scanning calorimetry in accordance with ASTM D3418-8. Specifically, this measurement is performed with a temperature profile as shown in FIG. I did it.

  That is, first, a toner to be measured is set on a differential scanning calorimeter (DSC-50) manufactured by Shimadzu Corporation equipped with an automatic tangential processing system, and heated from room temperature to 150 ° C. at a temperature rising rate of 10 ° C./min. (First temperature raising process) The relationship between temperature (° C.) and calorie (mW) was determined, and then cooled to 0 ° C. at a temperature lowering rate of 10 ° C./min. Data was collected by heating to 150 ° C. at the rate (second temperature rise process). At this time, each was held at 0 ° C. and 150 ° C. for 5 minutes.

  An example of the DSC curve (endothermic / exothermic curve) at this time is shown in FIG. 2 as a conceptual diagram. Curves as shown in FIG. 2 are obtained in both the first and second temperature raising processes, and for each of these, the peak end D of the endothermic peak based on melting of the crystalline polyester resin is represented by Tm1, and the rising portion from the baseline. The endothermic amount ΔH was determined from the area of (the part surrounded by connecting B and C).

Next, the configuration and manufacturing method of the electrostatic image developing toner of this embodiment will be described.
The toner for developing an electrostatic charge image of this embodiment contains at least a binder resin (binder resin) containing a crystalline resin and a release agent, and contains other components as necessary. The toner according to the exemplary embodiment will be described in detail with respect to each component.

(Binder resin)
The crystalline resin contained in the binder resin is not particularly limited as long as it is a crystalline resin, and specific examples include crystalline polyester resins and crystalline vinyl resins. The crystalline polyester resin is preferable from the viewpoints of adhesiveness and chargeability of the resin, and adjustment of the melting point within a preferable range. An aliphatic crystalline polyester resin having an appropriate melting point is more preferable. In the present embodiment, the “crystalline resin” refers to a resin having a clear endothermic peak instead of a stepwise endothermic amount change in differential scanning calorimetry (DSC). In the case of a polymer obtained by copolymerizing other components with respect to the crystalline polyester main chain, when the other components are 50% by mass or less, this copolymer is also called a crystalline resin.

Examples of the crystalline vinyl resin include amyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, and decyl (meth) acrylate. , Undecyl (meth) acrylate, tridecyl (meth) acrylate, myristyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, oleyl (meth) acrylate, behenyl (meth) acrylate, etc. And vinyl resins using long-chain alkyl and alkenyl (meth) acrylic acid esters.
In this specification, the description “(meth) acryl” means that both “acryl” and “methacryl” are included.

-Crystalline polyester resin-
-Crystalline resin-
The content of the crystalline resin contained in the toner base particles is preferably in the range of 2% by mass to 30% by mass, and more preferably in the range of 3% by mass to 15% by mass. If the content of the crystalline resin is less than 2% by weight, fixing in a low temperature region may be difficult. Further, if the content of the crystalline resin exceeds 30% by mass, gloss unevenness is likely to occur or filming is likely to occur particularly when fixing is performed in a middle temperature range or a high temperature range. The toner of the present embodiment preferably has an external additive added as will be described later. In this specification, the toner before the external additive is added may be referred to as “toner base particle”. .

  Further, the number average molecular weight (Mn) of the crystalline resin is preferably 5000 or more, and more preferably 7000 or more. If the number average molecular weight (Mn) is less than 7000, the toner may permeate into the surface of a recording medium such as paper at the time of fixing to cause uneven fixing, or the resistance to bending of the fixed image may be reduced. .

  As described above, a crystalline polyester resin, a crystalline vinyl resin, or the like can be used as the crystalline resin. However, the adhesiveness to the paper and the charging property at the time of fixing, and the melting point satisfying the above range can be easily obtained. From the viewpoint, it is preferable to use a crystalline polyester resin. In particular, an aliphatic crystalline polyester resin is more preferable because a resin having a desired melting point is easily obtained.

  Examples of the crystalline vinyl resin include amyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, and (meth) acrylic. Decyl acid, undecyl (meth) acrylate, tridecyl (meth) acrylate, myristyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, oleyl (meth) acrylate, (meth) acrylic acid Examples thereof include vinyl resins using long-chain alkyl such as behenyl and alkenyl (meth) acrylic acid esters. In the present specification, the description “(meth) acryl” means that both “acryl” and “methacryl” are included.

On the other hand, the crystalline polyester resin can be synthesized from a carboxylic acid (dicarboxylic acid) component and an alcohol (diol) component.
Hereinafter, the carboxylic acid component and the alcohol component will be described in more detail. In the present specification, the “crystalline polyester resin” also means a copolymer obtained by copolymerizing other components in a proportion of 50% by mass or less with respect to the main chain of the crystalline polyester resin.

  The carboxylic acid component is preferably an aliphatic dicarboxylic acid, and particularly preferably a linear carboxylic acid. For example, succinic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,11-undecanedicarboxylic acid Acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, etc., or lower alkyl esters thereof, Acid anhydrides can be mentioned but are not limited to these.

  The carboxylic acid component preferably contains constituent components such as a dicarboxylic acid component having a double bond and a dicarboxylic acid component having a sulfonic acid group in addition to the aliphatic dicarboxylic acid component described above. The dicarboxylic acid component having a double bond includes a component derived from a lower alkyl ester or acid anhydride of a dicarboxylic acid having a double bond, in addition to a component derived from a dicarboxylic acid having a double bond. Is also included. The dicarboxylic acid component having a sulfonic acid group includes a component derived from a dicarboxylic acid having a sulfonic acid group, a lower alkyl ester of a dicarboxylic acid having a sulfonic acid group, or an acid anhydride. Is also included.

  The dicarboxylic acid having a double bond can be suitably used to prevent hot offset at the time of fixing because the entire resin can be crosslinked using the double bond. Examples of the dicarboxylic acid include, but are not limited to, fumaric acid, maleic acid, 3-hexenedioic acid, and 3-octenedioic acid. Moreover, these lower alkyl esters, acid anhydrides, etc. are also mentioned. Among these, fumaric acid, maleic acid and the like are preferable in terms of cost.

  The dicarboxylic acid having a sulfonic acid group is effective in that it can favorably disperse a coloring material such as a pigment. Further, if the entire resin is emulsified or suspended in water to produce particles, if there is a sulfonic acid group, it can be emulsified or suspended without using a surfactant as described later. Examples of the dicarboxylic acid having a sulfonic acid group include, but are not limited to, 2-sulfoterephthalic acid sodium salt, 5-sulfoisophthalic acid sodium salt, and sulfosuccinic acid sodium salt. Moreover, these lower alkyl esters, acid anhydrides, etc. are also mentioned. Among these, 5-sulfoisophthalic acid sodium salt and the like are preferable in terms of cost.

  The content of the carboxylic acid component other than these aliphatic dicarboxylic acid components (dicarboxylic acid component having a double bond and / or dicarboxylic acid component having a sulfonic acid group) in the carboxylic acid component is 1 component mol% or more and 20 Constituent mol% is preferable, and 2 constituent mol% or more and 10 constituent mol% is more preferable.

When the content is less than 1 mol%, the dispersibility of the pigment in the toner base particles may deteriorate if a pigment is used as the colorant.
Further, when a toner is prepared using an emulsion polymerization aggregation method, the emulsion particle size in the dispersion becomes large, and it may be difficult to adjust the toner diameter by aggregation. On the other hand, if it exceeds 20 component mol%, the crystallinity of the crystalline polyester resin is lowered, the melting point is lowered, and the image storage stability may be deteriorated. Further, when a toner is prepared using an emulsion polymerization aggregation method, the emulsion particle size in the dispersion is too small, and thus subsequent aggregation may be difficult. In the present invention, “constituent mol%” refers to a percentage when each constituent component (carboxylic acid component, alcohol component) in the polyester resin is 1 unit (mol).

  On the other hand, the alcohol component is preferably an aliphatic diol, such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7. -Heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14 -Tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol and the like are exemplified, but not limited thereto.

The alcohol component preferably has an aliphatic diol component content of 80 constituent mol% or more, and includes other components as necessary. As the alcohol component, the content of the aliphatic diol component is more preferably 90 constituent mol% or more.

  When the content is less than 80 mol%, the crystallinity of the polyester resin is lowered and the melting point is lowered, so that toner blocking resistance, image storage stability and low-temperature fixability may be deteriorated. On the other hand, examples of other components included as necessary include diol components having a double bond and diol components having a sulfonic acid group.

  Examples of the diol having a double bond include 2-butene-1,4-diol, 3-butene-1,6-diol, 4-butene-1,8-diol, and the like. On the other hand, examples of the diol having a sulfonic acid group include 1,4-dihydroxy-2-sulfonic acid benzene sodium salt, 1,3-dihydroxymethyl-5-sulfonic acid benzene sodium salt, and 2-sulfo-1,4. -Butanediol sodium salt and the like.

  In the case of adding an alcohol component other than these linear aliphatic diol components (a diol component having a double bond and / or a diol component having a sulfonic acid group), the content in the alcohol component is one component mole. % Or more and 20 component mol% is preferable, and 2 component mol% or more and 10 component mol% is more preferable. When the content is less than 1 constituent mol%, pigment dispersion may be poor, the emulsified particle diameter may be large, and adjustment of the toner diameter by aggregation may be difficult. On the other hand, if it exceeds 20 component mol%, the crystallinity of the polyester resin is lowered, the melting point is lowered, the storage stability of the image is deteriorated, or the emulsified particle diameter is too small and it is difficult to cause subsequent aggregation. is there.

  The method for producing the crystalline polyester resin is not particularly limited, and can be produced by a general polyester polymerization method in which an acid component and an alcohol component are reacted. For example, direct polycondensation, transesterification method, etc. Depending on the type, it will be manufactured separately. The molar ratio (acid component / alcohol component) when the acid component reacts with the alcohol component varies depending on the reaction conditions and the like, and cannot be generally stated, but is usually about 1/1.

  The crystalline polyester resin can be produced at a polymerization temperature of 180 to 230 ° C., and the reaction system is depressurized as necessary to carry out the reaction while removing water and alcohol generated during the condensation. If the monomer is not dissolved or compatible at the reaction temperature, a high boiling point solvent is added as a solubilizer and dissolved. In the polycondensation reaction, the dissolution auxiliary solvent is distilled off. If there is a monomer with poor compatibility in the copolymerization reaction, it is advisable to condense the monomer with poor compatibility with the monomer and the acid or alcohol to be polycondensed in advance before polycondensing with the main component. .

  Catalysts that can be used in the production of the crystalline polyester resin include alkali metal compounds such as sodium and lithium, alkaline earth metal compounds such as magnesium and calcium, zinc, manganese, antimony, titanium, tin, zirconium, germanium and the like. A metal compound, a phosphorous acid compound, a phosphoric acid compound, an amine compound, etc. are mentioned, Specifically, the following compounds are mentioned.

  For example, sodium acetate, sodium carbonate, lithium acetate, lithium carbonate, calcium acetate, calcium stearate, magnesium acetate, zinc acetate, zinc stearate, zinc naphthenate, zinc chloride, manganese acetate, manganese naphthenate, titanium tetraethoxide, titanium Tetrapropoxide, titanium tetraisopropoxide, titanium tetrabutoxide, antimony trioxide, triphenylantimony, tributylantimony, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin oxide, zirconium tetrabutoxide, naphthene Zirconate, zirconyl carbonate, zirconyl acetate, zirconyl stearate, zirconyl octylate, germanium oxide, triphenyl Phosphite, tris (2,4-di -t- butyl-phenyl) phosphite, ethyltriphenylphosphonium bromide, triethylamine, compounds such as triphenyl amine.

  As melting | fusing point of the said crystalline polyester resin, it is preferable that it is the range of 60-120 degreeC, and it is more preferable that it is the range of 60-100 degreeC. When the melting point is less than 60 ° C., the melting point is lowered when the toner is formed, and it becomes difficult to maintain a melting point of 50 ° C. or higher necessary for the toner in the exemplary embodiment, and powder aggregation easily occurs. The storage stability of the fixed image may be deteriorated. On the other hand, when the temperature exceeds 120 ° C., even if the melting point is lowered due to the formation of toner, it is difficult to satisfy the melting point of 85 ° C. or less as the toner in this embodiment, and low-temperature fixing may not be possible.

  In this embodiment, the melting point of the crystalline resin is one of the points. This melting point is a melting point in a toner state (the same applies to the melting point of the release agent). The melting point of the crystalline resin as the material and the melting point of the toner using the same are closely related, but the relationship is the structure and blending ratio of the amorphous resin, which is one of the constituent requirements in this embodiment, or Since it varies depending on toner production conditions and the like, the melting point of the crystalline resin alone is not limited.

  In the present embodiment, the melting point of the crystalline resin is measured by ASTM D3418 when the differential scanning calorimeter (DSC) is used and the temperature is measured from room temperature to 150 ° C. at a heating rate of 10 ° C. per minute. It can be determined as the melting peak temperature of differential thermal analysis measurement based on -8. In the above measurement, a plurality of melting peaks may be shown. In the present embodiment, the maximum peak temperature is regarded as the melting point.

-Amorphous resin-
Examples of the amorphous resin used in the toner of the exemplary embodiment include conventionally known thermosetting binder resins, and specific examples include styrene such as styrene, parachlorostyrene, and α-methylstyrene. Homopolymers or copolymers (styrene resins); methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, methacrylic acid Homopolymers or copolymers of vinyl groups such as ethyl acetate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, etc .; vinyl nitriles such as acrylonitrile and methacrylonitrile Homopolymer or copolymer (vinyl resin); vinyl methyl ether, vinyl Homopolymers or copolymers of vinyl ethers such as butyl ether (vinyl resins); Homopolymers or copolymers of vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone (vinyl resins); ethylene , Homopolymers or copolymers of olefins such as propylene, butadiene, isoprene (olefin resins); non-vinyl condensation resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, And graft polymers of these non-vinyl condensation resins and vinyl monomers.
These resins may be used alone or in combination of two or more. Among these resins, vinyl resins and polyester resins are particularly preferable.

  The vinyl resin is advantageous in that a resin particle dispersion having an average particle size of 1 μm or less can be easily prepared by emulsion polymerization or seed polymerization using an ionic surfactant or the like. Examples of the vinyl monomer include acrylic acid, methacrylic acid, maleic acid, cinnamic acid, fumaric acid, vinyl sulfonic acid, ethylene imine, vinyl pyridine, vinyl amine, and other vinyl polymer acids and vinyl polymer bases. The monomer used as a raw material is mentioned preferably.

  In this embodiment, it is preferable that the resin particles contain the vinyl monomer as a monomer component. In the present embodiment, among these vinyl monomers, vinyl polymer acids are more preferable from the viewpoint of ease of formation reaction of vinyl resins, and specifically, acrylic acid, methacrylic acid, maleic acid, silica. A dissociative vinyl monomer having a carboxyl group as a dissociating group such as cinnamate and fumaric acid is particularly preferable in terms of controlling the degree of polymerization and the glass transition point.

  The concentration of the dissociating group in the dissociable vinyl monomer is determined by, for example, dissolving particles such as toner particles from the surface as described in Chemistry of Polymer Latex (Polymer Publication). Etc. can be determined. It should be noted that the molecular weight of the resin and the glass transition point from the surface of the particle to the inside can also be determined by the above method or the like.

  On the other hand, when a polyester resin is used as the amorphous resin in the toner of the present embodiment, the resin particle dispersion can be easily prepared by adjusting the acid value of the resin or emulsifying and dispersing using an ionic surfactant. It is advantageous in that it can be prepared. The amorphous polyester resin used for emulsification dispersion is synthesized by dehydration condensation of a polyvalent carboxylic acid and a polyhydric alcohol.

  Examples of polycarboxylic acids include terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid, and other aromatic carboxylic acids, maleic anhydride, fumaric acid, succinic acid, alkenyl Examples thereof include aliphatic carboxylic acids such as succinic anhydride and adipic acid, and alicyclic carboxylic acids such as cyclohexanedicarboxylic acid. These polyvalent carboxylic acids can be used alone or in combination. Of these polyvalent carboxylic acids, it is preferable to use aromatic carboxylic acids, and in order to take a crosslinked structure or a branched structure in order to ensure good fixability, tricarboxylic or higher carboxylic acids (trimerits) It is preferable to use an acid or an acid anhydride thereof in combination.

  Examples of polyhydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, glycerin, and other aliphatic diols, cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A And aromatic diols such as bisphenol A ethylene oxide adduct and bisphenol A propylene oxide adduct. One or more of these polyhydric alcohols can be used. Among these polyhydric alcohols, aromatic diols and alicyclic diols are preferable, and among these, aromatic diols are more preferable. In order to secure good fixing properties, a trihydric or higher polyhydric alcohol (glycerin, trimethylolpropane, pentaerythritol) may be used in combination with the diol in order to take a crosslinked structure or a branched structure.

  A polyester resin obtained by polycondensation of a polyvalent carboxylic acid and a polyhydric alcohol is further added with a monocarboxylic acid and / or monoalcohol to esterify the hydroxyl group and / or carboxyl group at the polymerization terminal, thereby producing a polyester. The acid value of the resin may be adjusted. Examples of the monocarboxylic acid include acetic acid, acetic anhydride, benzoic acid, trichloroacetic acid, trifluoroacetic acid, propionic anhydride and the like, and examples of the monoalcohol include methanol, ethanol, propanol, octanol, 2-ethylhexanol, and trifluoroethanol. , Trichloroethanol, hexafluoroisopropanol, phenol and the like.

There is no restriction | limiting in particular as a manufacturing method of the said polyester resin, The method similar to the method demonstrated in the said crystalline polyester resin can be used.
The weight average molecular weight of the amorphous resin in this embodiment is preferably in the range of 7000 to 100,000. The number average molecular weight is preferably in the range of 2500 to 20000. These molecular weights can be determined by molecular weight measurement (polystyrene conversion) by gel permeation chromatography.

  The glass transition temperature of the amorphous resin in the present embodiment is preferably in the range of 45 to 65 ° C, and more preferably in the range of 50 to 65 ° C. When the glass transition temperature is less than 45 ° C., the toner tends to easily block during storage or in the developing device (a phenomenon in which toner particles are aggregated into a lump). On the other hand, if the glass transition temperature exceeds 65 ° C., the fixing temperature of the toner becomes high, which is not preferable.

(Coloring agent)
There is no restriction | limiting in particular as a coloring agent in the toner of this embodiment, A well-known coloring agent is mentioned, It can select suitably according to the objective. One type of pigment may be used alone, or two or more types of pigments of the same type may be mixed and used. Two or more different types of pigments may be mixed and used.

  Specific examples of the colorant include carbon blacks such as furnace black, channel black, acetylene black, and thermal black; inorganic pigments such as bengara, aniline black, bitumen, titanium oxide, and magnetic powder; fast yellow and monoazo yellow Azo pigments such as disazo yellow, pyrazolone red, chelate red, brilliant carmine (3B, 6B, etc.), para brown, etc .; phthalocyanine pigments such as copper phthalocyanine, metal-free phthalocyanine; flavantron yellow, dibromoanthrone orange, perylene red, quinacridone red And condensed polycyclic pigments such as dioxazine violet;

  Chrome Yellow, Hansa Yellow, Benzidine Yellow, Slen Yellow, Quinoline Yellow, Permanent Orange GTR, Pyrazolone Orange, Vulcan Orange, Watch Young Red, Permanent Red, Dupont Oil Red, Resol Red, Rhodamine B Lake, Lake Red C, Rose Various pigments such as Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Phthalocyanine Green, Malachite Green Oxalate, Para Brown; Acridine, Xanthene, Azo, Benzoquinone, Azine, Anthraquinone, dioxazine, thiazine, azomethine, indigo, thioindigo, phthalocyanine, aniline black , Polymethine dyes, triphenylmethane dyes, diphenylmethane dyes, thiazole type, various dyes such as xanthene; and the like. You may mix black pigments, such as carbon black, and dye to such an extent that transparency is not reduced to these colorants. Moreover, a disperse dye, an oil-soluble dye, etc. are mentioned.

The content of the colorant in the electrostatic image developing toner of the exemplary embodiment is preferably in the range of 1 to 30 parts by mass with respect to 100 parts by mass of the binder resin, but the image surface smoothness after fixing is preferable. Of these numerical ranges, it is preferable that the number be as large as possible. Increasing the content of the colorant is advantageous in that the thickness of the image can be reduced when an image having the same density is obtained, and this is effective in preventing offset.
In addition, each color toner such as yellow toner, magenta toner, cyan toner, and black toner can be obtained by appropriately selecting the type of the colorant.

-Other ingredients-
As described above, the component constituting the toner of the present embodiment is not particularly limited as long as it contains at least a crystalline polyester resin and an amorphous resin as a binder resin. It may contain other components such as a mold agent. The method for producing the toner of the present embodiment is not particularly limited, but it is preferable to use a wet granulation method.

The release agent is generally used for the purpose of improving release properties.
Specific examples of the release agent include low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene; silicones having a softening point by heating; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide, and stearic acid amide Kinds: Plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax, jojoba oil; animal waxes such as beeswax; montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, Fischer-Tropsch wax, etc. And mineral / petroleum waxes; ester waxes such as fatty acid esters, montanic acid esters and carboxylic acid esters;

  In this embodiment, these mold release agents may be used individually by 1 type, and may use 2 or more types together. In particular, in the exemplary embodiment, it is preferable to use at least one release agent having a melting point Tmw on the higher temperature side than the peak temperatures Tmc and Tmc of the endothermic peak based on the crystalline polyester resin in the toner. The melting point of the low temperature crystalline resin is preferably in the range of 60 to 100 ° C, and the melting point of the high temperature releasing agent is preferably in the range of 70 to 105 ° C.

In addition, when two types of release agents are used, in addition to low temperature fixing based on sharp melting of the crystalline resin, the peeling characteristics on the low temperature side, the peeling characteristics on the high temperature side, and the anti-offset characteristics Can be improved.
The addition amount of these release agents is preferably in the range of 0.5 to 50% by mass, more preferably in the range of 1 to 30% by mass with respect to the total amount of toner.

As described above, the toner of the exemplary embodiment is preferably externally added with an inorganic abrasive and an inorganic additive having an average primary particle size of 50 nm to 100 nm.
The inorganic abrasive preferably has an average primary particle size of 100 nm or more and 1000 nm or less. Specifically, Si, Ti, Al, Mg, Ca, Sr, Ba, In, Ga, Ni, Mn, W , Fe, Co, Zn, Cr, Mo, Cu, Ag, V, Zr, Ce, and other oxides and composite oxides, and particularly silica, titania, alumina, zirconia, cerium, and the like are used. Further, these oxides exist between toner particles or between toner particles and the surface of the photosensitive member, a charging member, a cleaning member, and the like and serve to reduce the pressure at the contact, and therefore include a lubricating material. Is preferred. A typical lubricating material is fluorine treatment, and as fluorine-containing inorganic fine particles, raw ore (banestite) such as cerium oxide is pulverized, wet-treated, filtered, fired, crushed and classified.

  Or the method of processing with a fluorine-containing surface treating agent can also be used. The treating agent can be treated with a fluorine-containing silane compound such as trifluoropropyltrimethoxysilane, trifluoropropyltrichlorosilane, or tridecafluorodecyltrichlorosilane. The treatment amount is preferably 1 to 40 parts by mass, and more preferably 5 to 25 parts by mass. When the amount of treatment is less than the above range, the lubricity between toner particles or between toner particles and the surface of a photoreceptor, a charging member, a cleaning member, or the like may deteriorate.

  A preferable external addition amount of the inorganic abrasive in the toner of the present embodiment is preferably 0.5 parts by mass or more and 1.5 parts by mass or less, and 0.65 parts by mass or more and 1 part by mass with respect to 100 parts by mass of the toner base particles. More preferably, it is 35 parts by mass or less.

In addition, as the inorganic additive having a primary particle size of 50 nm to 100 nm (hereinafter sometimes referred to as “specific inorganic additive”), the average primary particle size is preferably 60 nm to 90 nm. Oxides such as Si, Ti, Al, Mg, Ca, Sr, Ba, In, Ga, Ni, Mn, W, Fe, Co, Zn, Cr, Mo, Cu, Ag, V, Zr, and Ce In particular, silica, titania, alumina, and the like are used, and silica, alumina, and titania prepared by a sol-gel method are particularly preferable from the viewpoint of uniform shape and particle diameter. The average primary particle size of the inorganic abrasive and the specific inorganic additive is determined by a known measuring machine such as Microtrac.
A preferable external addition amount of the specific inorganic additive in the toner of the exemplary embodiment is preferably 0.5 parts by mass or more and 2.5 parts by mass or less, and 0.7 parts by mass or more with respect to 100 parts by mass of the toner base particles. More preferably, it is 2.0 parts by mass or less.

  The other components that can be used in the toner of the exemplary embodiment are not particularly limited and may be appropriately selected depending on the purpose. Examples thereof include inorganic particles (other than the inorganic abrasive and the specific inorganic additive), organic materials. Well-known various additives, such as particle | grains, a charge control agent, etc. are mentioned.

The inorganic particles are generally used for the purpose of improving toner fluidity. Examples of the inorganic particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, cerium chloride. , Bengara, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, zirconium oxide, silicon carbide, silicon nitride and the like. Among these, silica particles are preferable, and silica particles that have been hydrophobized are particularly preferable.
The average primary particle diameter (number average particle diameter) of the inorganic particles is preferably in the range of 1 to 1000 nm, and the addition amount (external addition) is 0.01 to 20 mass with respect to 100 mass parts of the toner. A range of parts is preferred.

  The organic particles are generally used for the purpose of improving cleaning properties, transfer properties, and sometimes charging properties. Examples of the organic particles include particles such as polystyrene, polymethyl methacrylate, polyvinylidene fluoride, and polystyrene-acrylic copolymer.

  The charge control agent is generally used for the purpose of improving chargeability. Examples of the charge control agent include salicylic acid metal salts, metal-containing azo compounds, nigrosine and quaternary ammonium salts.

  The electrostatic image developing toner of the present embodiment may have a structure in which the surface of the core particle containing the binder resin is covered with a surface layer. The surface layer preferably does not significantly affect the mechanical properties and melt viscoelastic properties of the entire toner. For example, if the surface layer of non-melting or high melting point covers the toner thickly, the low-temperature fixability due to the use of the crystalline polyester resin cannot be sufficiently exhibited.

  Accordingly, the thickness of the surface layer is preferably as thin as possible, and specifically, is preferably in the range of 0.001 to 1 μm. In order to form a thin surface layer in the above range, a method of chemically treating the surface of particles containing binder resin, particles thereof, colorant, inorganic particles added if necessary, and other materials Are preferably used.

  Examples of the components constituting the surface layer include silane coupling agents, isocyanates, vinyl monomers, resins, and particles thereof. In addition, a polar group is preferably introduced into the component, and the adhesive force between the toner and a recording medium such as paper increases when chemically bonded.

The polar group may be any polar functional group, for example, carboxyl group, carbonyl group, epoxy group, ether group, hydroxyl group, amino group, imino group, cyano group, amide group, imide group , Ester groups, sulfone groups and the like.
In the present embodiment, the core particle surface is coated with a coating resin from the viewpoint of deteriorating powder fluidity due to exposure of a release agent or the like on the toner surface and suppressing blocking during storage. It is preferable.

  Chemical treatment methods include, for example, a strong oxidizing substance such as peroxide, a method of oxidizing by ozone oxidation, plasma oxidation, etc., a method of bonding a polymerizable monomer containing a polar group by graft polymerization, seed polymerization, etc. Can be mentioned.

Further, the surface layer may be provided by chemically or physically attaching the above-mentioned substance to the toner particle surface. For example, the resin particles can be coated with the toner on the outside of the toner base particles using mechanical force, and such a method is suitable for adjusting the charging characteristics of the toner base particles. Examples of the resin particles include styrene resin, styrene-acrylic copolymer, and polyester resin. Examples of the mixer used for coating include a sample mill, a Henschel mill, a V blender, and a hybridizer.
Furthermore, particles such as metals, metal oxides, metal salts, ceramics, resins, and carbon black may be further externally added for the purpose of improving chargeability, conductivity, powder flowability, lubricity, and the like.

  The volume average particle size of the toner in the exemplary embodiment is preferably in the range of 3 μm to 9 μm, and more preferably in the range of 3 μm to 8 μm. When the volume average particle size is less than 3 μm, the chargeability may be insufficient and the developability may be deteriorated, and when it exceeds 9 μm, the resolution of the image may be deteriorated.

As the particle size distribution index of the toner, the volume average particle size distribution index GSDv is at most 1.35, and the ratio GSDv / GSDp between the volume average particle size distribution index GSDv and the number average particle size distribution index GSDp is at least 0. .90 is preferable.
When the volume distribution index GSDv exceeds 1.35, the resolution of the image is deteriorated, and when GSDv / GSDp is less than 0.90, the chargeability may be deteriorated and at the same time, the image defect such as fogging and fogging. Can also cause

The volume average particle size and the particle size distribution index are smaller in volume and number than the particle size range (channel) obtained by dividing the particle size distribution measured using Coulter Multisizer-II type (manufactured by Beckman-Coulter). By subtracting the cumulative distribution from the particle size side, the particle size to be accumulated 16% is volume D16v, number D16p, the particle size to be accumulated 50% is volume D50v, number D50p, the particle size to be accumulated 84% is volume D84v, number It is defined as D84p.
The volume particle size distribution index GSDv is calculated as (D84v / D16v) ^1/2 , and the number average particle size distribution index GSDp is calculated as (D84p / D16p) ^1/2 .
The measurement is performed after the toner is dispersed in an electrolyte aqueous solution (isoton aqueous solution) and dispersed by ultrasonic waves for 30 seconds or more.

In addition, the shape factor SF1 of the toner of the present embodiment is preferably set to 110 ≦ SF1 ≦ 140 from the viewpoint of improving developability / transfer efficiency and improving image quality. This shape factor SF1 is obtained by the following equation (4).
SF1 = (ML ² / A) × (π / 4) × 100 (4)
In the formula (4), ML represents the maximum length of each particle, and A represents the projected area of each particle.

  When the shape factor SF1 is less than 110, generally, residual toner is generated in the transfer process during image formation. Therefore, it is necessary to remove the residual toner. However, the cleaning performance when the residual toner is cleaned with a blade or the like is required. It is easy to damage and may result in image defects. On the other hand, when the shape factor SF1 exceeds 140, when the toner is used as a developer, the toner may be destroyed due to collision with a carrier in the developing device. At this time, as a result, the amount of fine powder increases or the release agent component exposed on the toner surface may contaminate the surface of the photosensitive member and the like, and the charging characteristics may be impaired. May cause problems.

  The average value of the shape factor SF1 is obtained by taking 50 toner images magnified 250 times from an optical microscope into an image analyzer (LUZEX III, manufactured by Nireco), and calculating the individual particle size based on the maximum length and projected area. Is obtained by averaging the values of SF1.

(Manufacture of toner for developing electrostatic image)
The method for producing the electrostatic image developing toner of the present embodiment described above is not particularly limited, but it is particularly preferable to use a wet granulation method.
Suitable examples of the wet granulation method include known melt suspension methods, emulsion aggregation methods, and dissolution suspension methods, but the present embodiment is useful when using the emulsion aggregation method. The agglomeration method will be described as an example.

  The emulsion aggregation method includes an emulsification step of emulsifying the crystalline polyester resin or the like already described in the section of “Binder resin” in the present embodiment to form emulsified particles (droplets); ) And an aggregating step for fusing and aggregating the agglomerates.

-Emulsification process-
In the emulsification step, the emulsified particles (droplets) such as the crystalline polyester resin are subjected to shear force on a solution obtained by mixing an aqueous medium and a mixed solution (polymer solution) containing a resin and, if necessary, a colorant. Formed by giving.
At this time, the viscosity of the polymer liquid can be lowered to form emulsified particles by heating or dissolving the resin in the organic solvent. However, it is better not to use the organic solvent as much as possible from the viewpoint of environmental pollution. Moreover, a dispersing agent can also be used for stabilization of emulsified particles and thickening of the aqueous medium. Hereinafter, such a dispersion of emulsified particles may be referred to as a “resin particle dispersion”.

  Examples of the dispersant include water-soluble polymers such as polyvinyl alcohol, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, sodium polyacrylate, and sodium polymethacrylate, sodium dodecylbenzenesulfonate, sodium octadecylsulfate, and oleic acid. Anionic surfactants such as sodium, sodium laurate, potassium stearate, cationic surfactants such as laurylamine acetate, stearylamine acetate, lauryltrimethylammonium chloride, zwitterionic surfactants such as lauryldimethylamine oxide, Such as polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkylamine, etc. Anion surfactants such as surfactants, tricalcium phosphate, aluminum hydroxide, calcium sulfate, calcium carbonate, and inorganic compounds such as barium carbonate.

When an inorganic compound is used as the dispersant, a commercially available one may be used as it is, but a method of generating inorganic compound particles in the dispersant may be employed for the purpose of obtaining particles.
As the usage-amount of the said dispersing agent, the range of 0.01-20 mass parts is preferable with respect to 100 mass parts of said binder resins.

  In the emulsification step, when a crystalline polyester resin is used as the crystalline resin, a dicarboxylic acid having a sulfonic acid group is copolymerized (that is, the acid-derived constituent component has a sulfonic acid group). A suitable amount of a dicarboxylic acid-derived constituent component is included) and a dispersion stabilizer such as a surfactant can be reduced. However, if the amount of sulfonic acid groups is increased, emulsification can be facilitated, but the chargeability of the toner, particularly the chargeability under high temperature and high humidity, tends to deteriorate, so that the crystalline polyester resin of the present embodiment, as described above. It is preferable to design with a composition in which the sulfonic acid group content is as small as possible. Moreover, if the crystalline polyester resin is used, it is possible to form emulsified particles without using a dicarboxylic acid having a sulfonic acid group.

Examples of the organic solvent include ethyl acetate and toluene, which are appropriately selected according to the polyester resin.
The amount of the organic solvent used is 100 parts by mass with respect to a total amount of the crystalline resin or amorphous resin and other monomers used as necessary (hereinafter sometimes referred to simply as “polymer”). And the range of 50-5000 mass parts is preferable, and the range of 120-1000 mass parts is more preferable.

In addition, a colorant can be mixed before forming the emulsified particles. The colorant used is as already described in the section “Colorant” in the present embodiment.
Moreover, when using the crystalline polyester resin which reduced the said sulfone group amount, it can emulsify by reducing dispersion stabilizers, such as surfactant, by bringing pH at the time of emulsification to the alkaline side.

  Examples of the emulsifier used for forming the emulsified particles include a homogenizer, a homomixer, a cavitron, a clear mix, a pressure kneader, an extruder, and a media disperser. As the size of the emulsified particles (droplets) of the polyester resin, the average particle size (volume average particle size) is preferably in the range of 0.01 to 1 μm, more preferably in the range of 0.03 to 0.5 μm, A range of 0.03 to 0.4 μm is more preferable.

As a method for dispersing the colorant, any method such as a general dispersion method such as a rotary shear type homogenizer, a ball mill having a medium, a sand mill, or a dyno mill can be used, and is not limited at all.
If necessary, an aqueous dispersion of these colorants can be prepared using a surfactant, or an organic solvent dispersion of these colorants can be prepared using a dispersant. Hereinafter, such a dispersion of the colorant may be referred to as a “colored dispersion”. As the surfactant and the dispersing agent used for dispersion, the same dispersing agents that can be used when dispersing the polyester resin can be used.

The addition amount of the colorant is preferably in the range of 1 to 20% by mass, more preferably in the range of 1 to 10% by mass, with respect to the total amount of the polymer, in the range of 2 to 10% by mass. More preferably, it is more preferable to set it as the range of 2-7 mass%.
When the colorant is mixed in the emulsification step, the polymer and the colorant can be mixed by mixing the colorant or the organic solvent dispersion of the colorant with the organic solvent solution of the polymer. .

-Aggregation process-
In the agglomeration step, first, the obtained amorphous resin or emulsified particles of the crystalline resin, the colorant dispersion, and, if necessary, the release agent dispersion, the glass transition point of the amorphous resin or less. Aggregates by heating at a temperature and at a temperature not higher than the melting point of the crystalline resin (and further the release agent) to form aggregated particles.
Aggregates such as emulsified particles are formed by acidifying the pH of the emulsion under stirring. As the said pH, the range of 2-6 is preferable, The range of 2.5-5 is more preferable, The range of 2.5-4 is further more preferable. At this time, it is also effective to use a flocculant.

  As the flocculant to be used, a surfactant having a reverse polarity to the surfactant used for the dispersant, an inorganic metal salt, and a metal complex having a valence of 2 or more can be preferably used. In particular, the use of a metal complex is particularly preferable because the amount of the surfactant used can be reduced and the charging characteristics are improved.

  Examples of the inorganic metal salt include metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate, and inorganic substances such as polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide. Examples thereof include metal salt polymers. Among these, an aluminum salt and a polymer thereof are particularly preferable. In order to obtain a sharper particle size distribution, the valence of the inorganic metal salt is bivalent than monovalent, trivalent than bivalent, trivalent than trivalent, and tetravalent than trivalent. The inorganic metal salt polymer is more suitable.

  In the case where the surface of the aggregated particles is coated with resin as core particles, emulsified particles of the coating resin are added when the aggregated particles have reached a desired particle size. In this case, a flocculant may be further added or pH adjustment may be performed. The added emulsified particles of the coating resin adhere so as to cover the surface of the aggregated core particles. At this time, the emulsified particle diameter and the addition amount of the coating resin are adjusted so that the aggregated core particles can be sufficiently coated. In this way, aggregated particles coated with the emulsified particles of the coating resin are produced.

-Fusion process-
In the fusion step, under the same agitation as in the aggregation step, the pH of the suspension of the aggregated particles is increased to a range of 3 to 10 to stop the progress of aggregation, and the aggregation obtained through the aggregation step When the particles are in solution, the melting point of the crystalline resin contained in the aggregated particles, and the glass transition temperature of the amorphous resin (including the shell layer-constituting resin) (when there are two or more types of resin) Is heated to the lowest temperature of the glass transition temperature of the resin having the lowest glass point transition temperature) to fuse and coalesce to obtain toner particles.

  Further, in order to satisfy the relationship of the above formulas (1) and (2), when using a crystalline resin and a release agent having a ΔTm of 10 (° C.) or more and 30 (° C.) or less, when fusing and uniting Acid (for example, inorganic acid such as nitric acid, sulfuric acid, hydrochloric acid, sulfamic acid, or formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, isovaleric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, Oxalic acid, lactic acid, succinic acid, malic acid, citric acid and other organic acids) are added to adjust the pH to a range of 4.5 to 7.5 (preferably 5.0 to 7.0). Therefore, it is important to sufficiently incorporate a release agent that is generally hydrophobic. In addition, the compatibility of the release agent with the amorphous resin can be controlled. Specifically, it is possible to control within the range of 0.75 <ΔHh2 / ΔHh1 <0.95. Further, after the fusion / unification, the cooling rate during cooling is gradually cooled to a temperature slightly higher than the melting point of the crystalline resin (for example, the melting point of the crystalline resin + (5-7)) ° C. (for example, the cooling rate) 1 to 10 ° C./min), then rapidly cooled (for example, cooling rate: 15 to 30 ° C./min), rapidly cooled at a temperature near the melting point of the crystalline resin, and the crystalline resin has been melted It is also important not to enlarge the crystals by solidifying the.

  When a crystalline polyester resin is used as the crystalline resin, a dicarboxylic acid having a double bond is used as a copolymerization component of the crystalline polyester resin, and the polyester is used in the emulsification step, the aggregation step, and the fusion step. When the resin is heated to the melting point or higher, or after the completion of each step, the crosslinking reaction may be performed by heating separately. When the crosslinking reaction is performed, for example, an unsaturated crystalline polyester resin obtained by copolymerizing a double bond component as a binder resin is used, and a radical reaction is caused in the resin to introduce a crosslinked structure. At this time, a polymerization initiator shown below may be used.

  Examples of the polymerization initiator include t-butyl peroxy-2-ethylhexanoate, cumyl perpivalate, t-butyl peroxylaurate, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, di-t. -Butyl peroxide, t-butyl cumyl peroxide, dicumyl peroxide, 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 1,1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane 1,1-bis (t-butylperoxy) cyclohexane, 1,4-bis (t-butylperoxyca) Boniru) cyclohexane, 2,2-bis (t-butylperoxy) octane, n- butyl-4,4-bis (t-butylperoxy) Barireto, 2,2-bis (t-butylperoxy) butane,

1,3-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butyl) Peroxy) hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, di-t-butyldiperoxyisophthalate, 2,2-bis (4,4-di-t-butylper) Oxycyclohexyl) propane, di-t-butylperoxy-α-methylsuccinate, di-t-butylperoxydimethylglutarate, di-t-butylperoxyhexahydroterephthalate, di-t-butylperoxyazelate 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, diethylene glycol-bis (t-butylperoxycarbonate) Di-t-butylperoxytrimethyladipate, tris (t-butylperoxy) triazine, vinyltris (t-butylperoxy) silane, 2,2′-azobis (2-methylpropionamidine dihydrochloride), 2,2 Examples include '-azobis [N- (2-carboxyethyl) -2-methylpropionamidine], 4,4'-azobis (4-cyanovaleric acid) and the like.
These polymerization initiators can be used alone or in combination of two or more. The amount and type of the polymerization initiator are selected depending on the amount of unsaturated sites in the polymer and the type and amount of the coexisting colorant.

  The polymerization initiator may be mixed with the polymer in advance before the emulsification step, or may be incorporated into the aggregate in the aggregation step. Further, it may be introduced after the fusion step or after the fusion step. In the case of introduction after the aggregation step, the fusion step, or the fusion step, a solution in which the polymerization initiator is dissolved or emulsified is added to a particle dispersion (resin particle dispersion or the like). These polymerization initiators may be added with known crosslinking agents, chain transfer agents, polymerization inhibitors and the like for the purpose of controlling the degree of polymerization.

  The fused particles obtained by fusing can be made into toner particles through a solid-liquid separation process such as filtration and, if necessary, a washing process and a drying process. In this case, in order to ensure sufficient charging characteristics and reliability as a toner, it is preferable to sufficiently wash in the washing step.

  In the drying process, an arbitrary method such as a normal vibration type fluidized drying method, a spray drying method, a freeze drying method, or a flash jet method can be adopted. The toner particles are preferably adjusted to have a moisture content after drying of 1.0% by mass or less, preferably 0.5% by mass or less.

<Electrostatic image developer>
The electrostatic image developer of the present embodiment (hereinafter sometimes referred to as “developer of the present embodiment”) includes a toner, and the toner is the electrostatic image developing toner of the present embodiment described above. It is characterized by that.
The electrostatic charge image developing toner of the present embodiment is used as it is as a one-component developer or a two-component developer composed of a carrier, but a two-component developer excellent in charge maintenance and stability is preferable. .

  The carrier is preferably a carrier coated with a resin, and more preferably a carrier coated with a nitrogen-containing resin. Examples of the nitrogen-containing resin include acrylic resins including dimethylaminoethyl methacrylate, dimethylacrylamide, acrylonitrile and the like, amino resins including urea, urethane, melamine, guanamine, aniline, amide resins, and urethane resins. These copolymer resins may also be used. As the carrier coating resin, two or more of the nitrogen-containing resins may be used in combination. Moreover, you may use combining the said nitrogen containing resin and resin which does not contain nitrogen. The nitrogen-containing resin may be used in the form of particles and dispersed in a resin not containing nitrogen. In particular, urea resins, urethane resins, melamine resins, and amide resins have high negative chargeability and high resin hardness, so that a decrease in charge amount due to peeling of the coating resin can be effectively suppressed.

In general, the carrier needs to have an appropriate electric resistance value, and specifically, an electric resistance value of about 10 ⁹ to 10 ¹⁴ Ωcm is required. For example, when the electrical resistance value is as low as 10 ⁶ Ωcm as in the case of an iron powder carrier, the carrier adheres to the image portion of the photoreceptor due to charge injection from the sleeve, or the latent image charge escapes through the carrier, and the latent image In some cases, problems such as disturbance of the image or loss of images may occur. On the other hand, if an insulating resin (volume resistivity of 10 ¹⁴ Ωcm or more) is thickly coated, the electric resistance value becomes too high and carrier charges are less likely to leak, resulting in an edged image. On the other hand, there may be a problem of an edge effect that the image density in the central portion becomes very thin on a large image area. Therefore, it is preferable to disperse the conductive powder in the resin coating layer in order to adjust the resistance of the carrier.

  Specific examples of the conductive powder include metals such as gold, silver and copper; carbon black; semiconductive oxides such as titanium oxide and zinc oxide; titanium oxide, zinc oxide, barium sulfate, aluminum borate and potassium titanate. And the like, such as powder coated with tin oxide, carbon black, or metal. Among these, carbon black is preferable from the viewpoint of production stability, cost, and conductivity.

  Examples of the method for forming the resin coating layer on the surface of the carrier core material include an immersion method in which a powder of the carrier core material is immersed in the solution for forming the coating layer, and a solution for forming the coating layer on the surface of the carrier core material. Spraying method for spraying, fluidized bed method for spraying the solution for forming the coating layer in a state where the carrier core material is floated by flowing air, and a kneader for mixing the carrier core material and the coating layer forming solution in a kneader coater to remove the solvent. Examples of the coater method include a powder coating method in which a coating resin is formed into particles and mixed at a temperature equal to or higher than the melting point of the coating resin in a carrier core material and a kneader coater and then cooled to form a coating. The kneader coating method and the powder coating method are particularly preferably used. The average film thickness of the resin coating layer formed by the above method is usually in the range of 0.1 to 10 μm, more preferably 0.2 to 5 μm.

The core material (carrier core material) used for the carrier is not particularly limited, and examples thereof include magnetic metals such as iron, steel, nickel, and cobalt, or magnetic oxides such as ferrite and magnetite, glass beads, and the like. From the viewpoint of using the magnetic brush method, a magnetic carrier is preferable. As an average particle diameter of a carrier core material, generally 10-100 micrometers is preferable and 20-80 micrometers is more preferable.
The mixing ratio (mass ratio) of the toner and the carrier in the two-component developer is in the range of toner: carrier = 1: 100 to 30: 100, more preferably in the range of 3: 100 to 20: 100. preferable.

<Image forming apparatus>
Next, the image forming apparatus of this embodiment using the toner for developing an electrostatic charge image of this embodiment will be described.
The image forming apparatus according to the present embodiment is formed on a latent image holding member, a developing unit that develops an electrostatic image formed on the latent image holding member as a toner image with a developer, and the latent image holding member. The electrostatic charge image development of the present embodiment described above as the developer, comprising: a transfer unit that transfers the toner image onto the transfer member; and a fixing unit that fixes the toner image transferred onto the transfer member. An agent is used.

  In this image forming apparatus, for example, the part including the developing unit may have a cartridge structure (process cartridge) that can be attached to and detached from the image forming apparatus main body. As the process cartridge, a developer holding body is used. The process cartridge according to the present embodiment, which includes at least the above-described electrostatic charge image developer according to the present embodiment, is preferably used.

  In the image forming apparatus of the present embodiment, the process speed is preferably 350 mm / s or more, and more preferably 400 mm / s or more. The process speed is preferably 500 mm / s or less. The developer according to the present embodiment described above has an effect that low-temperature fixing is possible by suppressing gloss unevenness and a release member mark in a fixed image even in a high-speed operation at a process speed of 350 mm / s or more. . Here, the process speed represents the print speed. For example, in the case of 350 mm / s, it corresponds to 100 sheets of A4 (width 210 mm) per minute. Hereinafter, although an example of the image forming apparatus of this embodiment is shown, it is not necessarily limited to this. The main parts shown in the figure will be described, and the description of the other parts will be omitted.

  FIG. 1 is a schematic diagram showing a quadruple tandem full-color image forming apparatus. The image forming apparatus shown in FIG. 1 is a first to first electrophotographic method that outputs yellow (Y), magenta (M), cyan (C), and black (K) images based on color-separated image data. Fourth image forming units 10Y, 10M, 10C, and 10K (image forming means) are provided. These image forming units (hereinafter simply referred to as “units”) 10Y, 10M, 10C, and 10K are juxtaposed at a predetermined distance in the horizontal direction. The units 10Y, 10M, 10C, and 10K may be process cartridges that are detachable from the main body of the image forming apparatus.

Above each of the units 10Y, 10M, 10C, and 10K, an intermediate transfer belt 20 as an intermediate transfer member is extended through each unit. The intermediate transfer belt 20 is provided by being wound around a driving roller 22 and a support roller 24 that are in contact with the inner surface of the intermediate transfer belt 20 that are spaced apart from each other from the left to the right in the drawing. It is designed to travel in the direction toward 10K. The support roller 24 is urged away from the drive roller 22 by a spring or the like (not shown), and a predetermined tension is applied to the intermediate transfer belt 20 wound around the support roller 24. An intermediate transfer member cleaning device 30 is provided on the side surface of the latent image holding member of the intermediate transfer belt 20 so as to face the drive roller 22.
Further, each of the developing devices (developing means) 4Y, 4M, 4C, and 4K of the units 10Y, 10M, 10C, and 10K includes yellow, magenta, cyan, and black contained in the toner cartridges 8Y, 8M, 8C, and 8K. The four color toners can be supplied.

  Since the first to fourth units 10Y, 10M, 10C, and 10K described above have the same configuration, here, the first unit that forms a yellow image disposed on the upstream side in the intermediate transfer belt traveling direction. 10Y will be described as a representative. Note that the second to fourth units are denoted by reference numerals with magenta (M), cyan (C), and black (K) instead of yellow (Y) in the same parts as the first unit 10Y. Description of 10M, 10C, 10K is omitted.

The first unit 10Y has a photoreceptor 1Y that functions as a latent image holding member. Around the photoreceptor 1Y, an electrostatic charge image is formed by exposing the surface of the photoreceptor 1Y to a predetermined potential with a charging roller 2Y and the charged surface with a laser beam 3Y based on the color-separated image signal. An exposure device 3; a developing device (developing means) 4Y for supplying the charged toner to the electrostatic image and developing the electrostatic image; a primary transfer roller 5Y (primary) for transferring the developed toner image onto the intermediate transfer belt 20; A transfer unit), and a photoconductor cleaning device (cleaning unit) 6Y for removing toner remaining on the surface of the photoconductor 1Y after the primary transfer.
The primary transfer roller 5Y is disposed inside the intermediate transfer belt 20, and is provided at a position facing the photoreceptor 1Y. Further, a bias power source (not shown) for applying a primary transfer bias is connected to each of the primary transfer rollers 5Y, 5M, 5C, and 5K. Each bias power source varies the transfer bias applied to each primary transfer roller under the control of a control unit (not shown).

Hereinafter, an operation of forming a yellow image in the first unit 10Y will be described. First, prior to the operation, the surface of the photoreceptor 1Y is charged to a potential of about −600V to −800V by the charging roller 2Y.
The photoreceptor 1Y is formed by laminating a photosensitive layer on a conductive substrate (volume resistivity at 20 ° C .: 1 × 10 ⁻⁶ Ωcm or less). This photosensitive layer usually has a high resistance (a resistance equivalent to that of a general resin), but has a property that the specific resistance of the portion irradiated with the laser beam changes when irradiated with the laser beam 3Y. Therefore, a laser beam 3Y is output to the surface of the charged photoreceptor 1Y via the exposure device 3 in accordance with yellow image data sent from a control unit (not shown). The laser beam 3Y is applied to the photosensitive layer on the surface of the photoreceptor 1Y, whereby an electrostatic charge image of a yellow print pattern is formed on the surface of the photoreceptor 1Y.

The electrostatic charge image is an image formed on the surface of the photoreceptor 1Y by charging, and the specific resistance of the irradiated portion of the photosensitive layer is lowered by the laser beam 3Y, and the charged charge on the surface of the photoreceptor 1Y flows. On the other hand, this is a so-called negative latent image formed by the charge remaining in the portion not irradiated with the laser beam 3Y.
The electrostatic image formed on the photoreceptor 1Y in this way is rotated to a predetermined development position as the photoreceptor 1Y travels. At this development position, the electrostatic charge image on the photoreceptor 1Y is visualized (developed image) by the developing device 4Y.

  In the developing device 4Y, for example, yellow toner having a volume average particle diameter of 7 μm including at least a yellow colorant, a crystalline resin, and an amorphous resin is accommodated. The yellow toner is triboelectrically charged by being agitated inside the developing device 4Y, and has a charge of the same polarity (negative polarity) as the charged charge on the photoreceptor 1Y, and a developer roll (developer holder). Is held on. As the surface of the photoreceptor 1Y passes through the developing device 4Y, the yellow toner is electrostatically attached to the latent image portion on the surface of the photoreceptor 1Y, and the latent image is developed with the yellow toner. . The photoreceptor 1Y on which the yellow toner image is formed continues to run at a predetermined speed, and the toner image developed on the photoreceptor 1Y is conveyed to a predetermined primary transfer position.

When the yellow toner image on the photoreceptor 1Y is conveyed to the primary transfer, a predetermined primary transfer bias is applied to the primary transfer roller 5Y, and the electrostatic force directed from the photoreceptor 1Y to the primary transfer roller 5Y generates a toner image. The toner image on the photoreceptor 1 </ b> Y is transferred onto the intermediate transfer belt 20. The transfer bias applied at this time is a (+) polarity opposite to the polarity (−) of the toner, and is controlled to about +10 μA by the control unit (not shown) in the first unit 10Y, for example.
On the other hand, the toner remaining on the photoreceptor 1Y is removed and collected by the cleaning device 6Y.

Further, the primary transfer bias applied to the primary transfer rollers 5M, 5C, and 5K after the second unit 10M is also controlled according to the first unit.
Thus, the intermediate transfer belt 20 onto which the yellow toner image has been transferred by the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of the respective colors are superimposed and transferred in a multiple manner.

  The intermediate transfer belt 20 onto which the four color toner images have been transferred in multiple layers through the first to fourth units is disposed on the image transfer surface side of the intermediate transfer belt 20 and the support roller 24 in contact with the inner surface of the intermediate transfer belt 20. The secondary transfer roller (secondary transfer means) 26 is connected to a secondary transfer portion. On the other hand, the recording paper (transfer object) P is fed at a predetermined timing into a gap where the secondary transfer roller 26 and the intermediate transfer belt 20 are pressed against each other via a supply mechanism, and a predetermined secondary transfer bias is supported. Applied to the roller 24. The transfer bias applied at this time is a (−) polarity that is the same polarity as the polarity (−) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording paper P is applied to the toner image, and the transfer bias is applied to the intermediate transfer belt 20. The toner image is transferred onto the recording paper P. Note that the secondary transfer bias at this time is determined according to the resistance detected by a resistance detecting means (not shown) for detecting the resistance of the secondary transfer portion, and is voltage-controlled.

Thereafter, the recording paper P is sent to a fixing device (fixing means) 28, where the toner image is heated, and the color-superposed toner image is melted and fixed on the recording paper P. The recording paper P on which the color image has been fixed is carried out toward the discharge unit, and a series of color image forming operations is completed.
The image forming apparatus exemplified above is configured to transfer the toner image onto the recording paper P via the intermediate transfer belt 20, but the present invention is not limited to this configuration, and the toner image is directly transferred from the photoconductor. It may be a structure that is transferred to a recording sheet.

<Process cartridge, toner cartridge>
FIG. 2 is a schematic configuration diagram showing a preferred example of a process cartridge containing the electrostatic charge image developer according to the present embodiment. In the process cartridge 200, a charging roller 108, a developing device 111, a photoconductor cleaning device (cleaning means) 113, an opening 118 for exposure, and an opening 117 for static elimination exposure are attached to a rail 116 together with the photoconductor 107. Are combined and integrated with each other.
The process cartridge 200 is detachable from an image forming apparatus main body including a transfer device 112, a fixing device 115, and other components (not shown). It forms a forming apparatus. Reference numeral 300 denotes a recording sheet.

  The process cartridge shown in FIG. 2 includes a charging device 108, a developing device 111, a cleaning device (cleaning means) 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. Can be selectively combined. In the process cartridge according to the present embodiment, in addition to the photosensitive member 107, the charging device 108, the developing device 111, the cleaning device (cleaning means) 113, the opening 118 for exposure, and the opening 117 for static elimination exposure. At least one selected from the group consisting of:

  Next, the toner cartridge of this embodiment will be described. The toner cartridge according to this embodiment is detachably attached to the image forming apparatus. At least in the toner cartridge that stores toner to be supplied to the developing unit provided in the image forming apparatus, the toner is already present. It is the toner of the present embodiment described above. It should be noted that at least the toner may be stored in the toner cartridge of the present embodiment, and for example, a developer may be stored depending on the mechanism of the image forming apparatus.

  Therefore, in the image forming apparatus having a configuration in which the toner cartridge can be attached and detached, the storability is maintained even in the toner cartridge having a smaller container by using the toner cartridge containing the toner of the present embodiment. Therefore, it is possible to achieve low temperature fixing while maintaining high image quality.

  The image forming apparatus shown in FIG. 1 is an image forming apparatus having a configuration in which the toner cartridges 8Y, 8M, 8C, and 8K can be attached and detached, and the developing devices 4Y, 4M, 4C, and 4K are respectively the developing devices ( And a toner supply pipe (not shown). Further, when the amount of toner stored in the toner cartridge is low, the toner cartridge can be replaced.

  Hereinafter, although an Example and a comparative example are given and this embodiment is described in detail in detail, this embodiment is not limited to the following examples. In the following description, “part” represents “part by mass” and “%” represents “% by mass” unless otherwise specified.

<Measuring method of various characteristics>
First, methods for measuring physical properties of toners and the like used in Examples and Comparative Examples will be described.
(Toner particle size and particle size distribution measurement method)
In the present embodiment, the toner particle size and particle size distribution were measured using a Coulter Multisizer-II type (manufactured by Beckman Coulter, Inc.) as the measuring device, and ISOTON-II (manufactured by Beckman Coulter, Inc.) as the electrolyte.

  As a measurement method, 0.5 to 50 mg of a measurement sample is added to 2 ml of a 5% aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate, as a dispersant. This was added to 100 to 150 ml of the electrolytic solution. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute, and the particle size distribution of particles of 2 to 60 μm is measured using the Coulter counter TA-II type with an aperture diameter of 100 μm. The volume average particle diameter, GSDv, and GSDp were determined as described above. The number of particles to be measured was 50,000.

(Toner shape factor SF1 measurement method)
The toner shape factor SF1 is obtained by taking an optical microscope image of toner dispersed on a slide glass into a Luzex image analyzer through a video camera, and calculating the square of the maximum length of 50 toners / projection area (ML ² / A) × 100. It is obtained by calculating and obtaining an average value.

(Measurement method of molecular weight and molecular weight distribution of resin)
In this embodiment, the specific molecular weight distribution is performed under the following conditions. GPC uses “HLC-8120GPC, SC-8020 (manufactured by Tosoh Corporation)”, and the column uses two “TSKgel, SuperHM-H (6.0 mm ID × 15 cm, manufactured by Tosoh Corporation)” THF (tetrahydrofuran) was used as an eluent. As experimental conditions, an experiment was performed using a sample concentration of 0.5%, a flow rate of 0.6 ml / min, a sample injection amount of 10 μl, a measurement temperature of 40 ° C., and an IR detector. In addition, the calibration curve is “polystyrene standard sample TSK standard” manufactured by Tosoh Corporation: “A-500”, “F-1”, “F-10”, “F-80”, “F-380”, “A-2500”. ”,“ F-4 ”,“ F-40 ”,“ F-128 ”, and“ F-700 ”.

(Volume average particle diameter of resin particles, colorant particles, etc.)
Volume average particle diameters of resin particles, colorant particles, and the like were measured with a laser diffraction particle size distribution measuring apparatus (LA-700, manufactured by Horiba, Ltd.).

(Measuring method of resin, toner melting point, glass transition temperature and endotherm)
According to ASTM D3418-8, the melting point of the toner, crystalline polyester resin, and release agent of the present embodiment is a temperature profile as shown in FIG. 1 (the first rise for crystalline polyester resin and amorphous resin). It calculated | required from each maximum peak measured by temperature only.

Further, the endothermic amounts ΔHl1, ΔHl2, ΔHh1, and ΔHh2 were obtained from the peak areas of the endothermic peak portions with respect to the baseline in the first and second temperature rising processes.
A differential scanning calorimeter (manufactured by Shimadzu Corporation, DSC-60A) was used for the measurement.

<Production of toner>
(Preparation of amorphous resin particle dispersion)
A polyhydric alcohol component and a polyvalent carboxylic acid component having the composition shown in Table 1 are put into a round bottom flask equipped with a stirrer, a nitrogen introduction tube, a temperature sensor, and a rectifying tower, and the temperature is raised to 200 ° C. using a mantle heater. Allowed to warm. Next, nitrogen gas was introduced from the gas introduction tube, and the flask was stirred while maintaining an inert gas atmosphere. Then, amorphous resin (1)-(5) was obtained by adding 0.05 part of dibutyltin oxide with respect to 100 parts of raw material mixtures, and making it react for predetermined time, keeping the temperature of a reaction material at 200 degreeC. . The details are shown in Table 1.
Table 2 shows the physical properties of each resin.

Subsequently, the obtained amorphous resin was transferred in a molten state to an emulsifier (Cavitron CD1010, manufactured by Eurotech) at a rate of 100 g / min. In a separately prepared aqueous medium tank, 0.40% dilute aqueous ammonia diluted with reagent-exchanged ammonia water with ion-exchanged water is added and heated to 120 ° C. with a heat exchanger at a rate of 0.1 liter per minute. The polyester resin melt was transferred to the emulsifier at the same time. In this state, the emulsifier was operated under the conditions of the rotor rotation speed of 60 Hz and the pressure of 0.49 MPa (5 kg / cm ² ), and the volume average particle diameters were 0.15, 0.18, 0.23, 0.24 and 0.21 μm amorphous resin particle dispersions (1) to (5) (resin particle concentration: 30%) were obtained.

(Preparation of crystalline polyester resin particle dispersion)
-Crystalline polyester resin particle dispersion (1)
-1,12-dodecanoic acid: 952 parts-1,9-nonanediol: 656 parts-Fumaric acid: 30 parts-Dibutyltin: 2 parts

  The above components were mixed in a flask, heated to 220 ° C. under a reduced pressure atmosphere, and subjected to a dehydration condensation reaction for 6 hours to obtain a crystalline polyester resin. The melting point of the obtained resin was 75 ° C. Next, 80 parts of this crystalline polyester resin and 720 parts of deionized water were placed in a stainless beaker, placed in a warm bath and heated to 95 ° C. When the crystalline polyester resin melted, the mixture was stirred at 8000 rpm using a homogenizer (manufactured by IKA: Ultra Tarrax T50). Next, while an dropwise addition of 20 parts of an aqueous solution obtained by diluting 1.6 parts of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK) in 18.4 parts of ion-exchanged water, A crystalline polyester resin particle dispersion (1) (resin particle concentration: 10%) having a volume average particle size of 0.24 μm was obtained.

-Crystalline polyester resin particle dispersion (2)-
・ 1,10-decanoic acid: 840 parts ・ 1,9 nonanediol: 656 parts ・ Fumaric acid: 25 parts ・ Dibutyltin: 2.0 parts

  Using the above components, dehydration condensation was performed under the same conditions as in the preparation of the crystalline polyester resin particle dispersion (1) to obtain a crystalline polyester resin having a melting point of 71 ° C. Further, emulsification and dispersion were carried out in the same manner to obtain a crystalline polyester resin particle dispersion (2) (resin particle concentration: 10%) having a volume average particle size of 0.19 μm.

-Crystalline polyester resin particle dispersion (3)-
・ 1,10-decanoic acid: 840 parts ・ 1,10-decanediol: 712 parts ・ Fumaric acid: 15 parts ・ Dibutyltin: 2.0 parts

  Using the above components, dehydration condensation was performed under the same conditions as in the preparation of the crystalline polyester resin particle dispersion (1) to obtain a crystalline polyester resin having a melting point of 86 ° C. Furthermore, emulsification and dispersion were carried out in the same manner to obtain a crystalline polyester resin particle dispersion (3) (resin fine particle concentration: 10%) having a volume average particle size of 0.22 μm.

(Preparation of release agent dispersion)
-Release agent dispersion (1)-
-Paraffin wax FT-100 (melting point: 97 ° C, manufactured by Nippon Seiwa Co., Ltd.): 45 parts-Cationic surfactant (Neogen RK, Daiichi Kogyo Seiyaku): 5 parts-Ion-exchanged water: 200 parts After heating to 100 ° C. and sufficiently dispersing with IKA's Ultra Turrax T50, it is dispersed with a pressure discharge type gorin homogenizer, and a release agent dispersion having a volume average particle size of 185 nm and a solid content of 18% ( 1) was obtained.

-Release agent dispersion (2)-
-Paraffin wax FT-105 (melting point: 104 ° C, manufactured by Nippon Seiwa Co., Ltd.): 45 parts-Cationic surfactant (Neogen RK, Daiichi Kogyo Seiyaku): 5 parts-Ion-exchanged water: 200 parts After heating to 100 ° C. and sufficiently dispersing with IKA's Ultra Turrax T50, it is dispersed with a pressure discharge type gorin homogenizer, and a release agent dispersion having a volume average particle size of 185 nm and a solid content of 18% ( 2) was obtained.

-Release agent dispersion (3)-
・ Hi-Mic 1090 (melting point: 88 ° C., manufactured by Nippon Seiwa Co., Ltd.): 45 parts ・ Cationic surfactant (Neogen RK, Daiichi Kogyo Seiyaku): 5 parts ・ Ion-exchanged water: 200 parts And then sufficiently dispersed with IKA Ultra Turrax T50, and then dispersed with a pressure-discharge type gorin homogenizer, and a release agent dispersion (3) having a volume average particle size of 185 nm and a solid content of 18%. Got.

-Preparation of colorant dispersion-
-Cyan pigment (manufactured by Dainichi Seika Co., Ltd., Pigment Blue 15: 3 (copper phthalocyanine)): 1000 parts-Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen R): 150 parts-Ion-exchanged water: 4000 Part

  A colorant dispersion obtained by mixing, dissolving, and dispersing a colorant (cyan pigment) by dispersing for about 1 hour using a high-pressure impact disperser Ultimateizer (manufactured by Sugino Machine Co., Ltd., HJP30006). Prepared. The volume average particle size of the colorant (cyan pigment) in the colorant dispersion was 0.15 μm, and the colorant particle concentration was 20%.

<Example 1>
Amorphous resin particle dispersion (1): 170 parts Amorphous resin particle dispersion (3): 170 parts Crystalline polyester resin particle dispersion (1): 30 parts Release agent dispersion (1 ): 40 parts Colorant dispersion: 50 parts Flocculant dispersion, polyaluminum chloride (manufactured by Daimei Chemical Co., Ltd.): 5 parts Weigh the above ingredients into a stainless steel reaction vessel and add 2% -HCl aqueous solution Then, after adjusting the pH to 4, the mixture was mixed with Ultra Turrax (manufactured by IKA) at 5000 rpm for 5 minutes, and heated to 50 ° C. and aggregated at a rate of 1 ° C./m. The particle size was measured with a Coulter Counter-TA-II type (manufactured by Beckman Coulter). When the particle size reached 5.8 μ, 30 g of 4% -NaOH aqueous solution was added, and further heated to 95 ° C. for 2 hours. After holding, 2% -HCL aqueous solution was added to adjust pH to 6.5, and further held for 1 h. Thereafter, the toner was cooled to 81 ° C., which is the melting point of the crystalline polyester resin + 6 ° C., at a rate of 1 ° C./m, and then cooled to 30 ° C. at a rate of 30 ° C./m to obtain toner base particles.

To 100 parts of the obtained toner base particles, as additive 1, sol-gel silica having an average primary particle size of 75 nm (Wako Pure Chemicals, Tetramethoxysilane as a monomer, hydrolyzed under basic conditions, baked and pulverized. 1.5 parts of the resulting product) and additive 2 were used to contain fluorine-containing cerium oxide having an average primary particle size of 500 nm (obtained by further treating miracle 20 made by Mitsui Kinzoku Co., Ltd. with trifluoropropyltrichlorosilane). Three parts were added and external addition mixing was performed with a Henschel mixer to obtain a toner for developing an electrostatic charge image of Example 1.
Table 3 shows the melting point Tmc of the crystalline resin, the melting point Tmw (° C.), ΔHl2 / ΔHl1, and ΔHh2 / ΔHh1 of the crystalline resin measured by the above-described method of the obtained toner for developing an electrostatic image (hereinafter referred to as the following). The same applies to the electrostatic image developing toner.

-Production of electrostatic charge image developer-
A trifunctional isocyanate 80% ethyl acetate solution (into a carbon dispersion obtained by mixing 0.12 part of carbon black (trade name; VXC-72, manufactured by Cabot Corporation) with 1.25 parts of toluene and stirring and dispersing in a sand mill for 20 minutes. Takenate D110N, manufactured by Takeda Pharmaceutical Co., Ltd.) 1.25 parts of the coating agent resin solution and Mn—Mg—Sr ferrite particles (volume average particle size: 35 μm) were added to a kneader and mixed and stirred at room temperature for 5 minutes. Then, the temperature was raised to 150 ° C. at normal pressure to distill off the solvent. After further 30 minutes of mixing and stirring, the heater was turned off and the temperature was lowered to 50 ° C. The obtained coated carrier was sieved with a 75 μm mesh to prepare a carrier. 95 parts of this carrier and 5 parts of the electrostatic image developing toner of Example 1 were mixed in a V blender to obtain the electrostatic image developer of Example 1.

(Evaluation)
Using the obtained electrostatic charge image developer of Example 1, a solid image (weight per unit area of 13 to 15 g / m ² ) was formed at a process speed of 350 mm / min with an Apeos Port C75550I remodeling machine. The following evaluation was conducted. The results are shown in Table 4.
-Image sticking evaluation-
The above image was continuously printed on 157 g / m ² thick paper and allowed to cool on the print tray, and then the adhesion between the papers was observed every 10 sheets to confirm image transfer.
5: Good 4: Adhesion but no image transfer (only sound is generated and cannot be visually confirmed).
3: No problem in actual use, but can be confirmed visually.
2: There is a slight problem in actual use, and can be confirmed sufficiently visually.
1: There is a considerable problem in actual use.

-Evaluation of gloss unevenness-
100 sheets of the above image were printed on glossy paper (256 g / m ² ), and gloss unevenness in a portion where the image was not fixed was visually determined.
5: Good.
4: Level at which slight uneven gloss can be seen when held obliquely with a fluorescent lamp.
3: It is a level where uneven gloss can be seen when it is held obliquely with a fluorescent lamp, but there is no problem in actual use.
2: There is a slight problem in actual use, and can be confirmed sufficiently visually.
1: There is a considerable problem in actual use, and there are many unevenness in image gloss and the density is conspicuous.

-Releasing part mark evaluation-
The image on the glossy paper was confirmed in the same manner, and it was confirmed whether or not the solid image was scratched.
5: Good.
4: Level that can be confirmed to be slightly marked when held diagonally with a fluorescent lamp.
3: It is a level where you can see that it is marked when you hold it diagonally with a fluorescent light, but there is no problem in practical use.
2: There is a slight problem in actual use, and can be confirmed sufficiently visually.
1: There are considerable problems in actual use and many scratches.

-Storage stability evaluation-
Storage stability was evaluated by collecting 20 g of the obtained toner, storing it for 3 days at 55 ° C. and 50% RH, sucking the toner on a 20 μ stainless steel mesh, and sampling the coarse toner on the screen by tape transfer. And observed with a microscope.
5: Good (no coarseness).
4: Coarse but less than 5.
3: About 5 to 10 coarse powders, but loosening level.
2: Less than 10 to 20 coarse powders are not unraveled.
1: 20 or more coarse, 100μ or more is not unraveled.

<Example 2>
In Example 1, the crystalline polyester resin particle dispersion (1) was changed to the crystalline polyester resin particle dispersion (2), and the release agent dispersion (1) was changed to the release agent dispersion (3). The electrostatic charge image of Example 2 in the same manner as in Example 1 except that it was cooled to 77 ° C., which is the melting point of the conductive polyester, at 30 ° C./m, and then cooled to 30 ° C. at 1 ° C./m. A developer was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 4.

<Example 3>
In Example 1, 170 parts of the amorphous resin particle dispersion (1) and 170 parts of the amorphous resin particle dispersion (3) were replaced with 170 parts of the amorphous resin particle dispersion (2) and amorphous. Resin Particle Dispersion (4) In 170 parts, the crystalline polyester resin particle dispersion (1) is converted into the crystalline polyester resin particle dispersion (3), and the release agent dispersion (1) is released into the release agent dispersion (2 ), And after cooling at 30 ° C./m to 93 ° C., which is the melting point of the crystalline polyester + 7 ° C., the procedure was carried out in the same manner as in Example 1 except that the conditions were changed to 1 ° C./m. The electrostatic charge image developer of Example 3 was produced and evaluated in the same manner as in Example 1. The results are shown in Table 4.

<Example 4>
In Example 1, 170 parts of the amorphous resin particle dispersion (1) and 170 parts of the amorphous resin particle dispersion (3) were replaced with 170 parts of the amorphous resin particle dispersion (2) and amorphous. Resin particle dispersion (5) The electrostatic charge image developer of Example 4 in the same manner as in Example 1 except that 170 parts of the release agent dispersion (1) was changed to the release agent dispersion (2). The same evaluation as in Example 1 was performed. The results are shown in Table 4.

<Example 5>
In Example 1, 170 parts of the amorphous resin particle dispersion (1) and 170 parts of the amorphous resin particle dispersion (3) were replaced with 170 parts of the amorphous resin particle dispersion (2) and amorphous. Resin particle dispersion (5) In 170 parts, the crystalline polyester resin particle dispersion (1) is changed to the crystalline polyester resin particle dispersion (3), and the melting point of the crystalline polyester is + 7 ° C. up to 93 ° C. to 30 ° C. The electrostatic charge image developer of Example 5 was prepared in the same manner as in Example 1 except that it was changed to the condition of cooling at 1 ° C./m to 30 ° C. after cooling at / m, and the same evaluation as in Example 1 was made. Carried out. The results are shown in Table 4.

<Example 6>
In Example 1, the electrostatic charge image developer of Example 6 was produced in the same manner as in Example 1 except that fluorine-containing cerium oxide was not added, and the same evaluation as in Example 1 was performed. The results are shown in Table 4.

<Example 7>
In Example 1, the electrostatic charge of Example 6 was obtained in the same manner as in Example 1 except that fluorine-containing aluminum oxide obtained by treatment of fluorine-containing cerium oxide with trifluoropropylmethoxysilane and sol-gel silica was changed to sol-gel titania. An image developer was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 4.

<Example 8>
Evaluation was performed in the same manner as in Example 1 except that the process speed was changed to 400 mm / sec in Example 1. The results are shown in Table 4.

<Comparative Example 1>
In Example 1, the amount of the crystalline polyester resin dispersion was heated to 95 parts at 95 ° C. and held for 2 hours, and then the 2% -HCL aqueous solution was not added, and was further held for 2 hours. Thereafter, the toner mother particles were produced by cooling to 30 ° C. at a rate of 1 ° C./m, and the sol-gel silica having an average primary particle size of 75 nm added to the toner mother particles was changed to sol-gel silica having an average primary particle size of 105 nm. The electrostatic charge image developer of Comparative Example 1 was prepared in the same manner as Example 1 except that the same evaluation as in Example 1 was performed. The results are shown in Table 4.

<Comparative Example 2>
In Example 1, the amount of the crystalline polyester resin dispersion was heated to 70 parts at 110 ° C. and held for 2 hours, then 2% -HCL aqueous solution was added to adjust the pH to 4.0, and the mixture was further held for 0.5 hours. . Thereafter, an electrostatic charge image developer of Comparative Example 2 was prepared in the same manner as in Example 1 except that the toner was obtained by cooling to 30 ° C. at a rate of 30 ° C./m, and the same evaluation as in Example 1 was performed. did. The results are shown in Table 4.

<Comparative Example 3>
In Example 1, the amount of the crystalline polyester resin dispersion was heated to 110 parts at 110 ° C. and held for 2 hours, and then the 2% -HCL aqueous solution was not added, and was further held for 0.5 hours. Thereafter, the toner base particles are produced by cooling to 30 ° C. at a rate of 1 ° C./m, and the sol-gel silica having an average primary particle size of 75 nm added to the toner base particles is changed to sol-gel silica having an average primary particle size of 45 nm. Except that, the electrostatic charge image developer of Comparative Example 3 was produced in the same manner as in Example 1, and the same evaluation as in Example 1 was performed. The results are shown in Table 4.

<Comparative example 4>
In Example 1, the amount of the crystalline polyester resin dispersion was heated to 110 parts at 110 ° C. and held for 2 hours, and then the 2% -HCL aqueous solution was not added, and was further held for 0.5 hours. Thereafter, the toner mother particles are produced by cooling to 30 ° C. at a rate of 1 ° C./m, and the same as in Example 1 except that the fluorine-containing cerium oxide added to the toner mother particles is not added. An electrostatic charge image developer was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 4.

<Comparative Example 5>
In Example 1, the crystalline polyester resin dispersion was changed to (2) and the release agent dispersion was changed to (2), heated to 110 ° C. and held for 2 h, without adding a 2% -HCL aqueous solution, It was further maintained for 0.5 h. Thereafter, an electrostatic charge image developer of Comparative Example 5 was prepared in the same manner as in Example 1 except that the toner was obtained by cooling to 30 ° C. at a rate of 1 ° C./m, and the same evaluation as in Example 1 was performed. did. The results are shown in Table 4.

<Comparative Example 6>
In Example 1, the amount of the release agent dispersion was heated to 150 parts at 80 ° C. and maintained for 2 hours, then 2% -HCL aqueous solution was added to lower the pH to 4.0, and further maintained for 4.5 hours. Thereafter, an electrostatic charge image developer of Comparative Example 6 was prepared in the same manner as in Example 1 except that the toner was obtained by cooling to 30 ° C. at a rate of 30 ° C./m, and the same evaluation as in Example 1 was performed. did. The results are shown in Table 4.

It is a figure which shows the temperature profile of the differential scanning calorimetry in this embodiment. It is a conceptual diagram which shows an example of the endothermic and exothermic curve of the differential scanning calorimetry in this embodiment. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an exemplary embodiment. It is a schematic block diagram which shows an example of the process cartridge of this embodiment.

Explanation of symbols

1Y, 1M, 1C, 1K, 107 photoconductor (image carrier)
2Y, 2M, 2C, 2K, 108 Charging roller 3Y, 3M, 3C, 3K Laser beam 3 Exposure device 4Y, 4M, 4C, 4K, 111 Developing device (developing means)
5Y, 5M, 5C, 5K Primary transfer rollers 6Y, 6M, 6C, 6K, 113 Photoconductor cleaning device (cleaning means)
8Y, 8M, 8C, 8K Toner cartridge 10Y, 10M, 10C, 10K Unit 20 Intermediate transfer belt 22 Drive roller 24 Support roller 26 Secondary transfer roller (transfer means)
28, 115 Fixing device (fixing means)
30 Intermediate transfer member cleaning device 112 Transfer device 116 Mounting rail 117 Opening 118 for static elimination exposure Opening 200 for exposure Process cartridge,
P, 300 Recording paper (transfer object)

Claims (7)

Containing a crystalline resin and a release agent,
The absolute value ΔTm of the difference between the melting point Tmc (° C.) of the crystalline resin and the melting point Tmw (° C.) of the release agent is 10 (° C.) or more and 30 (° C.) or less,
In the differential scanning calorimetry according to ASTM D3418-8, the endothermic amount based on the endothermic peak on the low temperature side in the first temperature rising process is ΔHl1, the endothermic amount based on the endothermic peak on the high temperature side is ΔHh1, and the second temperature rising. In the process, when the endothermic amount based on the endothermic peak on the low temperature side is ΔHl2, and the endothermic amount based on the endothermic peak on the high temperature side is ΔHh2, the relationship of the following formulas (1) and (2) is satisfied. Toner for developing electrostatic images.
0.15 <ΔHl2 / ΔHl1 <0.45 (1)
0.75 <ΔHh2 / ΔHh1 <0.95 (2)   2. The electrostatic image developing toner according to claim 1, wherein an inorganic abrasive and an inorganic additive having an average primary particle diameter of 50 nm to 100 nm are externally added.   An electrostatic image developer comprising: a toner, wherein the toner is the electrostatic image developing toner according to claim 1.   A toner cartridge comprising at least a toner, wherein the toner is the electrostatic image developing toner according to claim 1.   A process cartridge comprising at least a developer holder and containing the electrostatic charge image developer according to claim 3.   A latent image holding member; developing means for developing the electrostatic image formed on the latent image holding member into a toner image with a developer; and transferring the toner image formed on the latent image holding member onto the transfer target member. An image forming apparatus comprising: a transfer unit configured to transfer image data; and a fixing unit configured to fix a toner image transferred onto a transfer target, wherein the developer is the electrostatic charge image developer according to claim 3. apparatus.   The image forming apparatus according to claim 6, wherein a process speed is 350 mm / s or more.