JP5262571B2 - Electrostatic image developing toner and method for producing the same, electrostatic image developer, toner cartridge, process cartridge, image forming method, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner excellent in low-temperature fixability, cleaning characteristic, and image quality. <P>SOLUTION: The electrostatic charge image developing toner contains toner mother particles containing polyester resin and an external additive, the average circularity of the toner mother particles is 0.95-0.985, the turbidity measured on the following condition is 35-60, and fatty acid metal salt of an average particle diameter of 2-4 &mu;m, and resin particles of an average particle diameter of 180-320 nm are contained in a supernatant liquid obtained on the following condition. A [turbidity measuring] toner of 5.0 g is dispersed into aqueous solution of 100 ml containing of nonionic surfactant of 1 ml, is shaken by an ultrasonic shaking machine for 3 minutes, and then is centrifuged at 2,000 rpm for 20 minutes, a supernatant liquid is sampled, and the haze value of the supernatant liquid is measured and is used as the turbidity of the toner. The supernatant liquid is further centrifuged at 10,000 rpm for 5 minutes, and the fatty acid metal salt and resin particles are detected using the obtained supernatant liquid. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

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

  The electrophotographic method generally uses a photoconductive substance, forms an electric latent image on the photoconductor by various means, and then converts the latent image into a toner composition containing a colorant (hereinafter simply referred to as “toner”). The toner image is transferred to a transfer material such as paper as necessary, and fixed with a heat roll or the like, and an image is obtained. It is cleaned in order to form an electrostatic latent image again.

  The dry developer used for such electrophotography is a one-component developer using a toner in which a colorant or the like is blended in a binder resin, and a two-component developer in which a carrier is mixed with the toner. Broadly divided. Since the latter half of the 1980s, the market for electrophotography has been strongly demanded for miniaturization and high functionality with the key to digitization. Particularly, regarding the image quality of full-color images, high-quality quality close to high-quality printing and silver salt photography is desired.

  As means for achieving high image quality, digitization processing is indispensable, and as an effect of digitization related to such image quality, it is mentioned that complex image processing can be performed at high speed. This makes it possible to control the character image and the photographic image separately, and the reproducibility of the quality of both images is greatly improved compared to the analog technology. In particular, for photographic images, gradation correction and color correction are possible, and this is advantageous compared to analog in terms of gradation characteristics, definition, sharpness, color reproduction, and graininess. However, on the other hand, it is necessary to faithfully create a latent image created by an optical system as an image output, and as a toner, an activity aiming at faithful reproduction is being accelerated as the particle size is increasingly reduced. It is difficult to stably obtain high image quality only by reducing the particle size of toner, and improvement of basic characteristics in development, transfer, and fixing characteristics is more important.

Dry developers can be broadly classified into one-component developers that use toner itself in which a colorant is dispersed in a binder resin, and two-component developers in which a carrier is mixed with the toner. In either case, when copying, the electrostatic latent image formed on the photoconductor is developed with these developers, the toner image on the photoconductor surface is transferred, and the toner remaining on the photoconductor surface is cleaned. To do. Therefore, the dry developer needs to satisfy various conditions in the copying process, particularly in the developing process or the cleaning process. That is, the toner is used for development in the form of individual particles, not as aggregates, during development, and for this purpose, the toner has sufficient fluidity, and this fluidity or electrical property. It is necessary not to change over time or with the environment (temperature, humidity).
Further, in the two-component developer, it is necessary to prevent the so-called toner filming phenomenon in which the toner adheres to the carrier surface.

  Further, in cleaning, it is necessary to have a cleaning property such that residual toner is easily detached from the surface of the photosensitive member and that the photosensitive member is not damaged when used with a cleaning member such as a blade or a web. In order to satisfy these various requirements, in a dry developer, a one-component developer or two-component developer in which inorganic fine powder such as silica, organic fine powder such as fatty acid, metal salt and derivatives thereof, and fluorine resin fine powder are externally added to the toner. Various developers have been proposed to improve fluidity, durability or cleaning properties.

Further, for example, Patent Documents 1 to 4 shown below are known.
Patent Document 1 discloses a toner obtained by externally adding two or more kinds of inorganic fine particles including large particle size inorganic fine particles L and small particle size inorganic fine particles S to colored particles including at least a colorant and a binder resin. There is disclosed an electrostatic charge image developer comprising a carrier, wherein the large particle size inorganic fine particles L and the small particle size inorganic fine particles S satisfy the following conditions (1) to (5).
<Conditions> ■ When the maximum volume distribution particle size of the large particle size inorganic fine particles L is D _L (nm), 50 ≦ D _L <150 ■ The maximum volume distribution particle size of the small particle size inorganic fine particles S is D _{When S} (nm), 10 ≦ D _S ≦ 50 ■ The ratio of the maximum volume distribution particle size D _{L to} the maximum volume distribution particle size D _S is 1.5 ≦ (D _L / D _S ) <5 0.0 The friction charge amount Q when the friction charge amount between the large particle size inorganic fine particles L and the carrier material is Q _L and the friction charge amount between the small particle size inorganic fine particles S and the carrier material is Q _S. the absolute value of the ratio of the triboelectric charge quantity _{Q S (Q S / Q L} ) with respect to _L is 0 to 0.5

Further, Patent Document 2 discloses a toner for developing electrostatic images comprising colored particles containing at least a colorant and a binder resin and fine particles having a number average particle diameter of 0.05 to 0.5 μm. An electrostatic charge image developing toner having a degree of 10 to 50 is disclosed.
Patent Document 3 discloses a non-magnetic one-component full color used in a developing device having a developing roll and a blade that applies a charge by frictional charging while uniformly controlling the thickness of a toner layer formed on the developing roll. In the toner, the toner comprises at least a binder resin mainly composed of a polyester resin, a resin fine particle composed of a colorant and a charge adjusting agent and an external additive, and the charge adjusting agent is represented by the general formula (I):

（式中、Ｘはアルカリ金属を示す）で表されるベンジル酸誘導体の金属塩および一般式（II）：

(Wherein X represents an alkali metal) and a metal salt of a benzylic acid derivative represented by formula (II):

（式中、Ｒ¹、Ｒ²およびＲ³はそれぞれ独立して水素原子、直鎖または分枝鎖状の炭素数１〜１０のアルキル基またはアリル基、Ｙは亜鉛、ニッケル、コバルト、銅およびクロムよりなる群から選ばれた１種を示す）で表されるサリチル酸誘導体の金属塩を含有することを特徴とする非磁性一成分用フルカラートナーが開示されている。

Wherein R ¹ , R ² and R ³ are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms or an allyl group, Y is zinc, nickel, cobalt, copper and A non-magnetic one-component full-color toner comprising a metal salt of a salicylic acid derivative represented by the formula (1) selected from the group consisting of chromium is disclosed.

  Patent Document 4 includes resin particles containing a colorant, inorganic fine particles having a volume average particle size of 30 to 150 nm, and organic fine particles having a volume average particle size of 50 to 200 nm made of a resin having an outflow start temperature of 200 ° C. or higher. A color toner is disclosed.

JP-A-7-28276 JP-A-9-319134 Japanese Patent Laid-Open No. 10-312089 JP-A-6-266152

  An object of the present invention is to provide an electrostatic image developing toner excellent in low-temperature fixability, cleaning properties and image quality.

The above-described problems of the present invention have been solved by means described in the following <1> to <7>.
<1> A toner base particle containing a polyester resin, a colorant and a release agent, and an external additive, the toner base particle has an average circularity of 0.95 to 0.985, and turbidity measured under the following conditions An electrostatic charge having a degree of 35 to 60 and containing a fatty acid metal salt having an average particle diameter of 2 to 4 μm and resin particles having an average particle diameter of 180 to 320 nm in the supernatant obtained under the following conditions. Image developing toner,
<Turbidity measurement>
Disperse 5.0 g of the electrostatic charge image developing toner in 100 ml of an aqueous solution containing 1 ml of a surfactant, take 3 minutes on an ultrasonic shaker, and then centrifuge at 2,000 rpm for 20 minutes, collect the supernatant, The haze value of the supernatant is measured, and is defined as the turbidity of the electrostatic image developing toner.
The fatty acid metal salt and the resin particles are detected in the supernatant obtained by further centrifuging the supernatant at 10,000 rpm for 5 minutes.

<2> A step of at least aggregating polyester resin particles, a colorant and a release agent in a dispersion to obtain aggregated particles, a step of heating and aggregating the aggregated particles to obtain toner base particles, an average of the toner base particles A step of externally adding a fatty acid metal salt having a particle diameter of 2 to 4 μm and resin particles having an average particle diameter of 180 nm to 320 nm to obtain an external additive; and an external additive having an average particle diameter of less than 180 nm is externally added to the external additive toner A process for producing an electrostatic image developing toner according to <1>, which comprises the step of:
<3> The electrostatic charge image developing toner according to <1> or the electrostatic charge image developer comprising the electrostatic image developing toner produced by the production method according to <2> and a carrier,
<4> a toner cartridge containing at least the electrostatic image developing toner according to <1> or the electrostatic image developing toner produced by the production method according to <2>;
<5> The developer holding member, and the electrostatic image developing toner according to <1> above, the electrostatic image developing toner produced by the production method according to <2>, or the above <3>. A process cartridge containing an electrostatic charge image developer
<6> A latent image forming step of forming an electrostatic latent image on the surface of the latent image holding member, and developing the electrostatic latent image formed on the surface of the latent image holding member with a developer containing toner to form a toner image. A developing step, a transferring step for transferring the toner image formed on the surface of the latent image holding member to the surface of the transfer member, a fixing step for fixing the toner image transferred to the surface of the transferring member, and the latent image holding member A step of cleaning the toner remaining on the latent image holding member with a cleaning blade in contact with the latent image holding member, wherein the developer is the electrostatic charge image developing toner according to <1> or the above <2>. An electrostatic image developing toner produced by the production method, or an image forming method using the electrostatic image developer according to <3>,
<7> a latent image holding body, a charging unit that charges the latent image holding body, an exposure unit that exposes the charged latent image holding body to form an electrostatic latent image on the latent image holding body, A developing unit that develops the electrostatic latent image with a developer to form a toner image, a transfer unit that transfers the toner image from the latent image holding member to the surface of the transfer target, and a transfer unit that is transferred to the surface of the transfer target. A fixing means for fixing the toner image, and a cleaning blade in contact with the latent image holding member, and the developer is the electrostatic charge image developing toner according to <1> or <2>. An image forming apparatus using the electrostatic image developing toner produced by the production method described above or the electrostatic image developer described in <3> above.

According to the invention described in <1>, it is possible to provide an electrostatic image developing toner excellent in low-temperature fixability, cleanability and image quality.
Further, according to the invention described in <2>, it is possible to provide a method for easily producing an electrostatic charge image developing toner excellent in low-temperature fixability, cleanability and image quality.
Further, according to the invention described in <3>, it is possible to provide an electrostatic charge image developer that is excellent in low-temperature fixability, cleanability, and image quality.
In addition, according to the invention described in <4>, it is possible to provide a toner cartridge containing an electrostatic charge image developing toner excellent in low-temperature fixability, cleanability and image quality.
Further, according to the invention described in <5>, it is possible to provide a process cartridge containing an electrostatic charge image developing toner or an electrostatic charge image developer that is excellent in low-temperature fixability, cleaning properties and image quality.
Further, according to the invention described in <6>, it is possible to provide an image forming method excellent in low-temperature fixability, cleanability and image quality.
Further, according to the invention described in <7>, it is possible to provide an image forming apparatus that is excellent in low-temperature fixability, cleanability, and image quality.

  The present invention is described in detail below.

(Electrostatic image developing toner)
The electrostatic charge image developing toner of the present invention (hereinafter also simply referred to as “toner”) includes toner base particles including a polyester resin, a colorant and a release agent, and an external additive, and the average circular shape of the toner base particles. The degree of turbidity is 0.95 to 0.985, the turbidity measured under the following conditions is 35 to 60, and the fatty acid metal salt having an average particle diameter of 2 to 4 μm and the average particle diameter in the supernatant obtained under the following conditions Resin particles of 180 nm to 320 nm are included.
<Turbidity measurement>
Disperse 5.0 g of the electrostatic charge image developing toner in 100 ml of an aqueous solution containing 1 ml of a nonionic surfactant, apply it to an ultrasonic shaker for 3 minutes, then centrifuge at 2,000 rpm for 20 minutes, and remove the supernatant. The sample is collected, and the haze value of the supernatant is measured to determine the turbidity of the electrostatic image developing toner.
The fatty acid metal salt and the resin particles are detected by further centrifuging the supernatant at 10,000 rpm for 5 minutes, and the resulting supernatant (hereinafter also referred to as “dispersion during turbidity measurement”). ).

  The electrostatic image developing toner of the present invention further comprises other components as necessary. Details of these components will be described later.

The toner according to the present invention satisfying the above-mentioned regulations has a fine rugged structure on the toner surface, a low surface energy property of the fatty acid metal salt, an adhesion state, and an adhesion state of the resin fine particles at the cleaning nip portion in blade cleaning, and a good cushioning property. And exhibiting a good spacer effect by combining the particle diameters of the two types of external additives, transfer efficiency after initial and long-term use, cleaning performance in blade cleaning, developer fluidity, especially at high temperatures Significant improvement in high humidity environment. Further, by using a polyester resin as the binder resin, both the above-described properties and low-temperature fixability are satisfied.
As described above, the average circularity of the toner base particles in the toner of the present invention is preferably 0.95 to 0.985, more preferably 0.955 to 0.985, and 0.96 to 0. More preferably, it is .985.
When the average circularity is less than 0.95, the irregularity of the toner increases and the surface area increases. As the surface area increases, the electrostatic adhesion increases and the transfer efficiency extremely decreases. In addition, the external additive is unevenly distributed in the toner surface recess, and the substantial function of the external additive (powder flowability imparting, cleaning property improvement) is also lowered.
On the other hand, when the circularity is larger than 0.985, since the toner approaches a spherical shape, the toner is easy to roll and the contact area with the transfer medium is reduced, so that the transfer efficiency is reduced and the cleaning nip portion is used for blade cleaning. As a result, the toner easily slips out of the blade, resulting in a cleaning failure.

Here, the average circularity is preferably measured with FPIA-2100 manufactured by Sysmex. This system employs a method in which particles dispersed in water or the like are measured by a flow-type image analysis method, and the aspirated particle suspension is guided to a flat sheath flow cell and converted into a flat sample flow by the sheath liquid. It is formed. By irradiating the sample stream with stroboscopic light, the passing particles were captured as a still image by the CCD camera through the objective lens. The captured particle image was subjected to two-dimensional image processing, and the equivalent circle diameter and circularity were calculated from the projected area and the perimeter. The equivalent circle diameter was calculated as the equivalent circle diameter from the area of the two-dimensional image with respect to each photographed particle. Regarding the circularity, at least 5,000 or more images were analyzed, and the average circularity was obtained by statistical processing.
Circularity = circle equivalent diameter perimeter / perimeter = [2 × (Aπ) ^1/2 ] / PM
(In the above formula, A represents the projected area and PM represents the perimeter.)
In addition, HPF mode (high resolution mode) was used for the measurement, and the dilution factor was 1.0. In analyzing the data, the number particle size analysis range was set to 2.0 to 30.1 μm and the circularity analysis range was selected to be 0.40 to 1.00 for the purpose of removing measurement noise.
When measuring the average circularity of the toner base particles from the toner to which the external additive has adhered, the measurement may be performed by removing the external additive from the toner. The difference between the measurement value measured with the toner with the external additive and the measurement value with the toner base particles is different even when measuring the toner with the external additive because the additive is not focused. It is an error range, and the measured value can be regarded as the average circularity of the toner base particles.

In the present invention, the turbidity of the toner is an index indicating the degree of adhesion of the external additive. In order to solve the conventional problems, the turbidity of the toner of the present invention is 35 to 60, and the turbidity measurement is performed. The dispersion liquid sometimes contains fatty acid metal salt having an average particle diameter of 2 to 4 μm and resin particles having an average particle diameter of 180 to 320 nm.
“The turbidity of the toner is 35 to 60” means that the toner adheres to the toner weaker than the state of being externally added relatively strongly for the purpose of improving powder flowability, and Indicates a state of strongly adhering to the toner, and is an effective means for quantifying the adhesion strength of an external additive having a lighter specific gravity than inorganic particles that exhibit an effect during transfer and cleaning.
By setting the turbidity of the toner to 35 to 60, in combination with the above-described toner shape effect, a good cushioning property is exhibited, and good characteristics are exhibited at the time of cleaning by transfer or blade cleaning. When the turbidity of the toner is less than 35, the cushioning property of the external additive is lowered, so that the transferability and the cleaning property may be lowered. On the other hand, when the turbidity exceeds 60, excessive external additive is added. This increases the amount of the agent, and causes secondary troubles such as adhesion to the photoreceptor and poor cleaning, which is not preferable.

In the present invention, the turbidity of the toner is defined as follows and can be measured.
Turbidity: Haze value (HAZE value) = 100 × (diffuse component of total transmission component) / (total transmission component).
The method for measuring the turbidity of the toner is shown below.
Disperse 5.0 g of toner in 100 ml of an aqueous solution containing 1 ml of a nonionic surfactant, take 3 minutes on an ultrasonic shaker, then centrifuge at 2,000 rpm for 20 minutes, collect the supernatant, and collect the supernatant. The haze value of the liquid is measured to determine the turbidity of the toner. Many of the toner components, free inorganic particles, and aggregated external additives (inorganic particles, fatty acid metal salts, resin particles) are precipitated by centrifugation.
The fatty acid metal salt and the resin particles are detected by further centrifuging the supernatant at 10,000 rpm for 5 minutes, and the resulting supernatant (hereinafter also referred to as “dispersion during turbidity measurement”). ).
More preferably, Neugen EA137 (Daiichi Kogyo Seiyaku Co., Ltd.) is used as the nonionic surfactant.
Moreover, it is preferable to perform the measurement of the haze value of a supernatant liquid with a Nippon Denshoku Industries Co., Ltd. turbidity measuring machine, and it is more preferable to carry out with Nippon Denshoku Industries Co., Ltd. COH-400.
When the turbidity value of the toner is large, it means that there are many fatty acid metal salts and resin particles having a relatively low specific gravity that contributes to improvement in transferability and cleaning performance by blade cleaning.
In the toner of the present invention, it is preferable to use a polyester resin as a binder resin for the toner because image storage properties such as low-temperature fixability, image glossiness, and fixed image strength due to affinity with paper are improved.

The toner of the present invention includes, as an external additive, a fatty acid metal salt having an average particle diameter of 2 to 4 μm (more preferably an average particle diameter of 2.5 to 3.5 μm) and an average particle diameter of 180 to 320 nm (more preferably an average particle diameter). It is preferable to include resin particles having a particle size of 200 to 300 nm. In addition, unless otherwise indicated, the average particle diameter in an external additive represents a volume average primary particle diameter.
Further, the dispersion at the time of turbidity measurement needs to contain at least a fatty acid metal salt having an average particle diameter of 2 to 4 μm and resin particles having an average particle diameter of 180 to 320 nm. When the average particle size of the fatty acid metal salt is smaller than 2 μm, or when the average particle size of the resin particles is smaller than 180 nm, a sufficient spacer effect cannot be expressed. Extremely reduced. On the other hand, when the average particle diameter of the fatty acid metal salt is larger than 4 μm, or when the average particle diameter of the resin particles is larger than 320 nm, the distribution in the toner tends to be unevenly distributed, so that a sufficient improvement effect is expected. Can not.
Therefore, transferability and cleaning properties can be kept good by externally adding particles having a particle size in the range of turbidity of 35-60.

The fatty acid metal salt in the present invention is preferably a metal salt of a saturated or unsaturated fatty acid having 10 or more carbon atoms.
Specific examples include aluminum stearate, indium stearate, gallium stearate, zinc stearate, lithium stearate, magnesium stearate, sodium stearate, aluminum palmitate, aluminum oleate and the like. Preferably mentioned.
Examples of the resin particles include all particles used as an external additive on a normal toner surface such as vinyl resin, polyester resin, and silicone resin. Among these, polymethyl methacrylate resin particles are preferably used.

(Other external additives)
In addition to the fatty acid metal salt having an average particle diameter of 2 to 4 μm and the resin particles having an average particle diameter of 180 to 320 nm, the toner of the present invention includes other external additives such as a fluidizing agent and an auxiliary agent on the toner particle surface. It is preferable.
Other external additives include silica particles whose surfaces have been hydrophobized, titanium oxide particles, alumina particles, cerium oxide particles, inorganic particles such as carbon black, and polymer particles such as polycarbonate, polymethyl methacrylate, and silicone resin. Particles can be used. Among these, it is preferable to use at least two or more other external additives, more preferably 2 to 5 types as other external additives, and three types as other external additives. Is more preferable. At least one of the external additives preferably has an average primary particle size in the range of 30 nm to 200 nm, and preferably has an average primary particle size in the range of 30 nm to 180 nm. Moreover, when using an organic particle as another external additive, it is preferable to have an average primary particle diameter in the range of less than 180 nm.

By reducing the particle size of the toner, non-electrostatic adhesion to the photosensitive member increases, which may cause transfer defects and image loss of fine lines and cause transfer unevenness such as superimposed images. The transferability can be improved by adding an external additive having an average primary particle size of 30 nm to 200 nm.
In addition, inorganic particles, particularly silica particles, may be subjected to various surface treatments. For example, those subjected to surface treatment with a silane coupling agent, a titanium coupling agent, silicone oil or the like are preferably used.

Furthermore, it is preferable that inorganic particles are not contained in the dispersion during turbidity measurement.
The absence of the inorganic particles in the dispersion at the time of turbidity measurement indicates that the adhesion state of the inorganic particles to the toner is sufficiently strong. With the above embodiment, toner powder fluidity is excellent, and inorganic particles can be prevented from aggregating and adhering to the photoreceptor or being scratched.

As described above, the toner of the present invention includes toner base particles including a polyester resin, a colorant, and a release agent.
Further, the toner of the present invention may contain other additives in the toner base particles or as an external additive, if necessary.

-Polyester resin-
The toner of the present invention contains a polyester resin.
The binder resin in the toner of the present invention is preferably a polyester resin as a main component. Further, the binder resin in the toner of the present invention preferably contains an amorphous polyester resin, and more preferably contains an amorphous polyester resin and a crystalline polyester resin.
The polyester resin that can be used in the present invention is obtained, for example, mainly by polycondensation of polyvalent carboxylic acids and polyhydric alcohols.

Examples of the polyvalent carboxylic acids include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid; maleic anhydride, fumaric acid, succinic acid, alkenyl Aliphatic carboxylic acids such as succinic anhydride and adipic acid; and alicyclic carboxylic acids such as cyclohexanedicarboxylic acid, and one or more of these polycarboxylic acids can be used.
Among these polyvalent carboxylic acids, it is preferable to use aromatic carboxylic acids, and in order to ensure good fixability, trivalent or higher carboxylic acids that can form a crosslinked structure or a branched structure together with the dicarboxylic acid (trivalent). It is preferable to use merit acid or its acid anhydride in combination.

Examples of the polyhydric alcohol include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, glycerin; 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 better fixing properties, a trihydric or higher polyhydric alcohol (glycerin, trimethylolpropane, pentaerythritol, etc.) capable of forming a crosslinked structure or a branched structure may be used in combination with the diol.

  The glass transition temperature (Tg) of the polyester resin is preferably 40 ° C. or higher and 80 ° C. or lower, and more preferably 50 ° C. or higher and 70 ° C. or lower. Within the above range, the low-temperature fixing property and the heat storage property are excellent, and the storage stability of the fixed image is excellent.

Further, the polyester resin that can be used in the toner of the present invention preferably has an acid value of 5 mgKOH / g or more and 20 mgKOH / g or less. If it is 5 mgKOH / g or more, the toner has good affinity for paper and good chargeability. Further, when the toner is produced by the emulsion aggregation method described later, it is easy to produce emulsion particles, and it is possible to suppress the aggregation speed in the aggregation process of the emulsion aggregation method and the shape change speed in the coalescence process from being significantly increased. Therefore, it is easy to perform particle size control and shape control. Further, if the acid value of the polyester resin is 25 mgKOH / g or less, the environmental dependency of charging is not adversely affected, and the aggregation rate in the aggregation process and the shape in the coalescence process in toner production by the emulsion aggregation method are not affected. Since it can suppress that a change rate becomes remarkably slow, the fall of productivity can be prevented.
The acid value of the polyester resin is more preferably 6 mgKOH / g or more and 18 mgKOH / g or less.

The toner of the present invention preferably contains a crystalline polyester resin, and more preferably contains an amorphous polyester resin and a crystalline polyester resin.
The crystalline polyester resin is compatible with the non-crystalline polyester resin when melted, and the toner viscosity is remarkably lowered. Therefore, a toner having better low-temperature fixability and image gloss can be obtained. Of the crystalline polyester resins, aromatic crystalline resins are generally higher than the melting point range, and are preferably aliphatic crystalline polyester resins.
The content of the crystalline polyester resin in the toner of the present invention is preferably 2% by weight or more and 20% by weight or less, and more preferably 4% by weight or more and 18% by weight or less based on the total weight of the toner. Within the above range, both low-temperature fixability and chargeability can be achieved.

  The melting point of the crystalline polyester resin is preferably in the range of 50 ° C. to 100 ° C., more preferably in the range of 55 ° C. to 95 ° C., and further in the range of 60 ° C. to 90 ° C. preferable. When the melting point is 50 ° C. or higher, the toner storage stability and the storage stability of the toner image after fixing are excellent.

  “Crystalline polyester resin” refers to a polyester resin having a Bragg angle 2θ having peaks at 21.5 ° and 24 ° in an X-ray diffraction spectrum, and “noncrystalline polyester resin”. Indicates that the above two peaks cannot be confirmed. The crystalline polyester resin is a polymer obtained by copolymerizing another component with respect to the main chain. When the other component is 50% by weight or less, this copolymer is also called a crystalline polyester resin.

  The crystalline polyester resin is preferably synthesized from an acid (dicarboxylic acid) component and an alcohol (diol) component. In the following, “acid-derived component” refers to a component part that was an acid component before the synthesis of the polyester resin in the polyester resin, and “alcohol-derived component” refers to an alcohol before the synthesis of the polyester resin. Refers to the component site that was the component.

[Acid-derived components]
Examples of the acid for forming the acid-derived constituent component include various dicarboxylic acids.
The acid-derived constituent component in the crystalline polyester resin is preferably a linear aliphatic dicarboxylic acid.
For example, succinic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic 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 And acid anhydrides, but are not limited thereto. Of these, adipic acid, sebacic acid, and 1,10-decanedicarboxylic acid are preferable in view of availability.

  As the acid-derived component, other components such as a dicarboxylic acid-derived component having a double bond and a dicarboxylic acid-derived component having a sulfonic acid group may be contained.

  In the present specification, “constituent mol%” means that the acid-derived constituent component in the entire acid-derived constituent component in the polyester resin or the alcohol constituent component in the entire alcohol-derived constituent component is 1 unit (mol). ) Indicates the percentage.

[Alcohol-derived components]
As alcohol for becoming an alcohol component, aliphatic diol is preferable.
For example, 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-dodecanediol, 1,12-undecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20 -Eicosanediol and the like may be mentioned, but not limited thereto. Among these, in consideration of availability and cost, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferable. .

  The molecular weight (weight average molecular weight; Mw) of the crystalline polyester resin is preferably 8,000 or more and 40,000 or less from the viewpoint of resin manufacturability, fine dispersion during toner production, and compatible toner during melting, More preferably, it is 10,000 or more and 30,000 or less. Since the resistance fall of crystalline polyester resin can be suppressed as it is 8,000 or more, the fall of charging property can be prevented. When it is 40,000 or less, the cost of resin synthesis is suppressed, and the low temperature fixability is not adversely affected in order to prevent the sharp melt property from being lowered.

  The molecular weight of the polyester resin is preferably measured and calculated by GPC (Gel Permeation Chromatography). Specifically, HPC-8120 manufactured by Tosoh Corporation was used for GPC, TSKgel SuperHM-M (15 cm) manufactured by Tosoh Corporation was used for the column, and the polyester resin was measured with a tetrahydrofuran (THF) solvent. Next, the molecular weight of the polyester resin was calculated using a molecular weight calibration curve prepared with a monodisperse polystyrene standard sample.

  There is no restriction | limiting in particular as a manufacturing method of a polyester resin, It can manufacture with the general polyester polymerization method which makes an acid component and an alcohol component react. For example, direct polycondensation, transesterification, and the like are used depending on the type of monomer. The molar ratio (acid component / alcohol component) at the time of reacting the acid component with the alcohol component varies depending on the reaction conditions and the like, and thus cannot be generally described. However, in order to increase the molecular weight, it is usually 1/1. The degree is preferred.

  Catalysts that can be used in the production of the polyester resin include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; metal compounds such as zinc, manganese, antimony, titanium, tin, zirconium, and germanium; Examples thereof include phosphorous acid compounds; phosphoric acid compounds; and amine compounds.

In addition to the polyester resin, other resins may be used in combination as the binder resin.
Other resins include: ethylene resins such as polyethylene and polypropylene; styrene resins such as polystyrene and α-polymethylstyrene; (meth) acrylic resins such as polymethyl methacrylate and polyacrylonitrile; polyamide resins, polycarbonate resins, Examples include polyether resins and copolymer resins thereof.

-Colorant-
The toner of the present invention contains a colorant.
The colorant may be a dye or a pigment, but is preferably a pigment from the viewpoint of light resistance and water resistance.
For example, carbon black, aniline black, aniline blue, calcoil blue, chrome yellow, ultramarine blue, dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, lamp black, rose bengal, quinacridone, benzy Thin Yellow, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 185, C.I. I. Pigment red 238, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 74, C.I. I. Pigment blue 15: 1, C.I. I. A known pigment such as CI Pigment Blue 15: 3 can be used.

In the electrostatic charge image developing toner of the present invention, the content of the colorant is preferably 1 part by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the binder resin.
It is also effective to use a colorant that has been surface-treated as necessary, or a pigment dispersant. By appropriately selecting the type of the colorant, yellow toner, magenta toner, cyan toner, black toner and the like can be obtained.

-Release agent-
The toner of the present invention contains a release agent.
The release agent that can be used in the toner of the present invention is not particularly limited. However, the release agent having an acid value is easily compatible with the binder resin, and the effect as the release agent is reduced. Therefore, paraffin waxes such as low molecular weight polypropylene and low molecular weight polyethylene are preferred.
The melting point of these release agents is preferably 60 ° C. or higher and 100 ° C. or lower, and more preferably 65 ° C. or higher and 95 ° C. or lower. Within the above range, the toner is excellent in storage stability and fluidity, the image density is sufficient, occurrence of image defects such as trimmer clogging (white streaks) due to solidification of the toner can be suppressed, and the toner image and the fixing are fixed during fixing. The mold release agent exudes efficiently between the surface of the member and is excellent in offset property at high temperature.
In addition, by using Fischer-Tropsch wax among paraffin waxes, an image forming apparatus having any process speed from a low speed region to a high speed region has good offset resistance in a high temperature region. In addition, when the cleaning means is blade cleaning, the blade cleaning aptitude is excellent.
If a wax other than paraffin wax or Fischer-Tropsch wax is used as a mold release agent, if there is suitability at low process speeds, it is said that there is no suitability at high process speeds. You may not be able to.
The content of the release agent in the toner of the present invention is preferably 3 to 15% by weight and more preferably 3 to 12% by weight with respect to the total weight of the toner. When the amount is within the above range, a sufficient release effect can be obtained at the time of fixing, the hot offset resistance is excellent, and the storage stability is excellent.

-Other additives-
In addition to the above-described components, various known components such as an internal additive, a charge control agent, inorganic particles, and organic particles as described below are added to the toner according to the exemplary embodiment as necessary. be able to.

  Examples of the internal additive include metals such as ferrite, magnetite, reduced iron, cobalt, nickel, and manganese, magnetic materials such as alloys, or compounds containing these metals, and inhibit charging properties as toner characteristics. A small amount can be used.

The charge control agent is not particularly limited, but when a color toner is used, a colorless or light color can be preferably used. Examples thereof include quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments.
The inorganic particles are added for various purposes such as external addition or internal addition as described above, but are used for improving toner powder fluidity, as a transfer aid, or for adjusting viscoelasticity in the toner. May be added. By adjusting the viscoelasticity, it is possible to adjust the image glossiness and the penetration into the paper.
As the inorganic particles, for example, known inorganic particles such as silica particles, titanium oxide particles, alumina particles, cerium oxide particles, or those obtained by hydrophobizing these surfaces may be used alone or in combination of two or more kinds. However, silica particles having a refractive index smaller than that of the binder resin are preferably used from the viewpoint that transparency such as color developability and OHP transparency is not impaired. Further, the silica particles may be subjected to various surface treatments, and for example, those subjected to surface treatment with a silane coupling agent, a titanium coupling agent, silicone oil or the like are preferably used.
The organic particles are added for various purposes such as external addition or internal addition as described above, and known particles such as polymer particles such as polycarbonate, polymethyl methacrylate, and silicone resin can be used.

[Toner characteristics]
The toner of the present invention has a volume average particle diameter D ₅₀ of preferably 3 μm or more and 9 μm or less, more preferably 3.5 μm or more and 8.5 μm or less, and further preferably 4 μm or more and 8 μm or less. If the volume average particle diameter is 3 μm or more, a decrease in toner fluidity can be suppressed, and the chargeability of each particle can be easily maintained. In addition, the charge distribution does not spread, preventing fogging on the background and preventing toner from spilling from the developer. Further, when the volume average particle diameter of the toner is 3 μm or more, the cleaning property is improved. If the volume average particle size is 9 μm or less, a decrease in resolution can be suppressed, so that a sufficient image quality can be obtained and the recent demand for high image quality can be satisfied.

The volume average particle diameter D ₅₀ is, for example, a particle size range (channel) divided based on a particle size distribution measured by a measuring instrument such as Coulter Counter TAII, Coulter Multisizer II (manufactured by Beckman-Coulter). The cumulative distribution of volume and number is drawn from the smaller diameter side, the particle size that is 16% cumulative is the volume D _16v , the number D _16P , the particle size that is the cumulative 50% is the volume D _50v , the number D _{50P is} cumulative The particle size at 84% is defined as volume D _84v and number D _84P . Using these, the volume average particle size distribution index (GSDv) is calculated as ( _D84v / _D16V ) ^1/2 .

<Method for producing toner for developing electrostatic image>
The toner of the present invention can be produced by a known kneading / pulverizing method, a chemical production method such as an emulsion polymerization aggregation method or a suspension polymerization method, etc., but a toner having excellent shape controllability can be produced. In addition, it is preferable to produce a toner by an emulsion polymerization aggregation method from the viewpoint of yield and environmental load. First, the production method using the emulsion polymerization aggregation method will be described in detail.
The emulsion aggregation method is a method of preparing dispersions (emulsion liquid, pigment dispersion liquid, etc.) each containing components (binder resin, colorant, etc.) contained in the toner, and mixing these dispersion liquids to combine the toner components. In this method, aggregated particles are produced by agglomeration, and then the aggregated particles are heated to the melting point or glass transition temperature of the binder resin or higher to thermally fuse the aggregated particles.
The emulsion aggregation method is easier to produce toner with a smaller particle size and has a narrower particle size distribution than the kneading and pulverization method which is a dry method, the melt suspension method and the dissolution suspension method which are other wet methods. Easy to obtain uniform toner. Further, the shape control is easier than in the melt suspension method, the dissolution suspension method, and the like, and a uniform amorphous toner can be produced. Furthermore, it is possible to control the structure of the toner, such as film formation, and when it contains a release agent or crystalline polyester resin, the surface exposure of these can be suppressed, thus preventing deterioration of chargeability and storage stability. can do.

Next, the manufacturing process of the emulsion aggregation method will be described in detail.
The emulsion aggregation method includes at least an emulsification step of emulsifying a raw material constituting the toner to form resin particles (emulsion particles), an aggregation step of forming aggregates of the resin particles, and a fusion step of fusing the aggregates. And have. Hereinafter, an example of a toner manufacturing process using an emulsion aggregation method will be described for each process.

-Emulsification process-
Examples of the method for preparing the emulsion include phase inversion emulsification and melt emulsification.
In the phase inversion emulsification method, a resin to be dispersed is dissolved in a hydrophobic organic solvent in which the resin is soluble, and a base is added to the organic continuous phase (Oil phase; O) to neutralize it. Thereafter, by introducing an aqueous medium (Water phase; W), the water in oil (W / O) system is changed to an oil in water (O / W) system, so that the resin present in the organic continuous phase Phase into a discontinuous phase. As a result, the resin can be dispersed and stabilized in the form of particles in the aqueous medium to prepare an emulsion.
In the melt emulsification method, an emulsified liquid can be prepared by applying a shearing force to a solution obtained by mixing an aqueous medium and a resin with a disperser. At that time, particles can be formed by heating to lower the viscosity of the resin component. In addition, a dispersant may be used to stabilize the dispersed resin particles. Furthermore, if the resin is oily and has a relatively low solubility in water, dissolve the resin in a solvent and disperse the particles together with the dispersant and polymer electrolyte in water, and then heat or reduce the pressure. By evaporating the solvent, an emulsion in which the resin particles are dispersed can be prepared.

  As an apparatus for mixing and emulsifying and dispersing the binder resin and the release agent with an aqueous medium, for example, a homomixer (Special Machine Industries Co., Ltd.), or a slasher (Mitsui Mine Co., Ltd.), Cavitron (( Eurotech), Microfluidizer (Mizuho Kogyo Co., Ltd.), Menton Gorin Homizer (Gorin), Nanomizer (Nanomizer Co., Ltd.), Static Mixer (Noritake Company Limited), etc. Examples thereof include an emulsifier / disperser.

  Examples of the aqueous medium include water such as distilled water and ion-exchanged water; alcohols; however, it is preferable to use only water.

  Examples of the dispersant used in the emulsification step include water-soluble polymers such as polyvinyl alcohol, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, sodium polyacrylate, and sodium polymethacrylate; sodium dodecylbenzenesulfonate. Anionic surfactants such as sodium octadecyl sulfate, sodium oleate, sodium laurate, potassium stearate, cationic surfactants such as laurylamine acetate, stearylamine acetate, lauryltrimethylammonium chloride, lauryldimethylamine oxide, etc. Zwitterionic surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene Surfactants such as nonionic surfactants down alkylamines, and the like. Of these, anionic surfactants are generally used from the viewpoint of easy cleaning and environmental suitability.

  The content of the resin particles contained in the emulsion in the emulsification step is preferably in the range of 10% by weight to 50% by weight, and more preferably in the range of 20% by weight to 40% by weight. When the content is 10% by weight or more, the particle size distribution is not excessively widened, and deterioration of toner characteristics can be prevented. On the other hand, if it is 50% by weight or less, it is possible to stir without variation and to obtain a toner having a narrow particle size distribution and uniform characteristics.

  The size of the resin particles is preferably 0.08 μm or more and 0.6 μm or less, more preferably 0.09 μm or more and 0.5 μm or less, and 0.10 μm or more and 0.4 μm or less in terms of the average particle diameter (volume average particle diameter). Is more preferable. If it is 0.08 μm or more, the resin particles tend to aggregate. On the other hand, when the particle size is 0.6 μm or less, the particle size distribution of the toner is difficult to spread and the precipitation of the emulsified particles can be suppressed, so that the storage stability of the emulsified particle dispersion is improved.

Before entering the aggregating step described below, it is preferable to prepare a dispersion liquid in which a colorant, a release agent, and the like, which are toner components other than the binder resin, are dispersed.
In addition to the method of preparing a dispersion corresponding to each component such as a binder resin and a colorant, for example, when preparing an emulsion of a certain component, other components may be added to the solvent to add two or more The components may be emulsified at the same time so that the dispersed particles contain a plurality of components.

-Aggregation process-
In the coagulation step, the dispersion of the polyester resin particles obtained in the emulsification step, and the colorant dispersion, the release agent dispersion, etc. are mixed to form a mixed solution and heated at a temperature not higher than the glass transition temperature of the polyester resin. To form aggregated particles.
Aggregated particles can be formed by making the pH of the mixed solution acidic with stirring.
As pH, the range of 2-7 is preferable, The range of 2.2-6 is more preferable, The range of 2.4-5 is further more preferable.
It is also possible to produce a toner having a core-shell structure for the purpose of improving the storage stability and chargeability of the toner. In this case, after producing the agglomerated particles (primary agglomerated particles (core)), a raw material resin dispersion that becomes a shell is further added to the dispersion, and the shell material particles are attached to the primary agglomerated particles. It is necessary to coat the primary agglomerated particles. By doing so, it becomes a structure in which the adhering particles as the shell are coated around the primary aggregated particles of the core in the next fusion step.

  It is also effective to use a flocculant when forming the agglomerated particles. As the flocculant, a divalent or higher-valent metal complex can be suitably used in addition to a surfactant having a reverse polarity to the surfactant used for the dispersant and an inorganic metal salt. 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 polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide. Examples thereof include inorganic 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 divalent, tetravalent than trivalent, and even if the valence is the same, the polymerization type The inorganic metal salt polymer is more suitable.

  Further, when a toner having a structure in which the surface of the aggregated particles is coated with the raw material particles as in the present invention, a flocculant may be added or the pH may be adjusted before the raw material fine particle dispersion is additionally added.

-Fusion process-
In the fusing step, the agglomeration is stopped by increasing the pH of the suspension of the agglomerated particles or adhering particles to a range of 4 to 8 under the stirring conditions in accordance with the agglomeration step. The aggregated particles are fused by heating at a temperature equal to or higher than the transition temperature. As the alkaline solution used for increasing the pH, an aqueous NaOH solution is preferable from the viewpoints of volatility, safety, and solubility.

  The heating time may be as long as the fusion is performed, and is preferably 0.5 hours or more and 10 hours or less. Cooling is performed after the aggregated particles are fused to obtain fused particles. Also, in the cooling process, the cooling rate is increased in the vicinity of the melting point of the mold release agent and polyester resin (melting point ± 10 ° C range), so-called rapid cooling suppresses recrystallization of the mold release agent and polyester resin. Exposure may be suppressed.

  Through the above steps, a toner can be obtained as fused particles. The fused particles (toner) obtained by fusing need to be washed through a solid-liquid separation process such as filtration as described later.

-Washing process-
Since the toner obtained in the fusing process contains a large amount of surfactant and acid and alkali added to control aggregation and fusing, the degree of washing in this washing process is This is an important step regarding the charging property of the toner. In order to sufficiently clean the toner so that it does not adversely affect the chargeability of the toner, the main cleaning step includes (1) a step of washing the toner with a treatment liquid having a pH of 9 to 10, and (2) further solidifying the toner. After the liquid separation, washing is preferably performed by a washing step including a step of washing with ion-exchanged water at a temperature of 20 to 33 ° C. at least 20 times the solid content of the toner.
Hereinafter, the toner cleaning process will be described by dividing it into the above two processes.

[Step of washing with treatment liquid of pH 9 or more and pH 10 or less]
First, the toner obtained in the fusing step is washed with a treatment liquid having a pH of 9 or more and a pH of 10 or less.
Specifically, the toner is dispersed in ion-exchanged water, adjusted to a pH of 9 to 10 at a temperature of 20 ° C. to 40 ° C., and washed with stirring.
If the temperature is 20 ° C. or higher, the detergency does not deteriorate. If the temperature is 40 ° C. or lower, the toner surface can be prevented from being rough. Moreover, if pH is 9 or more, carboxylic acid will fully dissociate and the adsorbed surfactant can be removed. In addition, it is more preferable to use an aluminum-based flocculant because it is easy to remove the bound surfactant due to a change in aluminum ions. A pH of 10 or less is preferable because hydrolysis hardly occurs.
Next, the toner and the dispersion medium are solid-liquid separated from the toner dispersion. Thereafter, the toner is further dispersed in ion-exchanged water at 30 ° C. and stirred with a mechanical stirrer. The step of re-dispersing in water after the solid-liquid separation and stirring is repeated until the conductivity in the toner dispersion becomes 100 μs or less.

[Step of washing with ion exchange water at least 20 times the solid amount of toner]
Next, the toner and the dispersion medium are solid-liquid separated from the toner dispersion by suction filtration. Thereafter, the toner is first dispersed in ion-exchanged water having a 10-fold water temperature of 28 ° C. to 33 ° C. with respect to the solid content, and stirred with a mechanical stirrer. When the toner solid content on the cake that has hardened by suction filtration is uniformly dispersed in ion-exchanged water, solid-liquid separation is performed again by suction filtration. Again, the toner is dispersed in ion-exchanged water having a 10-fold amount and a water temperature of 28 ° C. to 33 ° C. with respect to the solid content, and stirred with a mechanical stirrer. After the solid-liquid separation, if the filtrate is 50 μs or less, the washing step is completed. If the filtrate is larger than 50 μs, the solid-liquid separation and redispersion steps may be further washed with ion-exchanged water. preferable.
Moreover, it is preferable that the water temperature of the ion exchange water used at the said process is 28 to 33 degreeC. When the temperature is 28 ° C. or lower, the cleaning effect is hardly exhibited. When the temperature is 33 ° C. or higher, the toner surface may be roughened.
After the toner cleaning, the solid-liquid separated toner is dried with a freeze vacuum dryer, a shelf dryer, a hot air dryer or the like.
The moisture content of the toner after drying is preferably 1.5% by weight or less, and more preferably 1.2% by weight or less.

The toner production method of the present invention includes a step of aggregating at least polyester resin particles, a colorant, and a release agent in a dispersion to obtain agglomerated particles, and heating and aggregating the agglomerated particles to obtain toner base particles. A step of externally adding a fatty acid metal salt having an average particle size of 2 to 4 μm and resin particles having an average particle size of 180 nm to 320 nm to the toner base particles to obtain an externally added toner, and an average particle size of 180 nm to the externally added toner It is preferable to include a step of externally adding less than the external additive.
The step of aggregating the resin particles, the colorant and the release agent in the dispersion to obtain aggregated particles, and the step of heating and aggregating the aggregated particles to obtain toner base particles include the above-described aggregation step and fusion step. It is preferable to carry out similarly. In addition, the toner production method of the present invention preferably includes the other steps described above.

In the toner production method of the present invention, a toner base particle containing polyester resin particles, a colorant and a release agent, a fatty acid metal salt having an average particle diameter of 2 to 4 μm, a resin particle having an average particle diameter of 180 nm to 320 nm, and It is preferable to externally add an external additive having an average particle size of less than 180 nm.
As the external additive having an average particle size of less than 180 nm, it is preferable to use two or more kinds of inorganic particles such as silica particles, titanium oxide particles, cerium oxide particles, and carbon black whose surfaces have been hydrophobized. Is more preferable, and it is more preferable to use three kinds of particles.
Further, at least one kind of external additive having an average particle size of less than 180 nm is preferably silica particles, more preferably silica particles having different particle sizes, and further preferably combined use of titanium oxide particles.

The external additive is added to the toner base particles by externally adding a fatty acid metal salt having an average particle diameter of 2 to 4 μm and resin particles having an average particle diameter of 180 nm to 320 nm to the toner base particles. The method preferably includes a step of obtaining, and a step of externally adding an external additive having an average particle size of less than 180 nm to the externally added toner.
When blending external additives to the toner, it is necessary to blend the toner, fatty acid metal salt and resin particles in advance with the toner separately from the inorganic particle external additive to be used together, and then add the inorganic particle external additive There is. When external addition blending is performed simultaneously with the inorganic particle external additive, inorganic particles having a relatively large specific gravity are selectively attached to the toner surface, and the adhesion state is strongly externally added. Fatty acid metal salts and resin particles having a small specific gravity tend to adhere weakly. Then, these weakly attached external additives are easily released and may not function during transfer or cleaning. In addition, when blended simultaneously, it becomes easy to form inorganic fine particles and aggregates, and even if the additive is originally expected to have a fluidity-imparting function, the inorganic particles are not uniformly distributed on the toner surface. In addition, sufficient powder fluidity is not exhibited, and there is a possibility of filming on the photoreceptor.
On the other hand, by blending the fatty acid metal salt and the resin particles with the toner in advance prior to the inorganic particles as in the above-described toner manufacturing method, the toner fluidity of the toner is not adversely affected and the blades are transferred. At the time of cleaning, it exhibits a good cushioning property with an appropriate spacer effect and balance with the toner shape, and good transferability and cleaning properties can be maintained even after long-term use.

Specific examples of the apparatus used for the external addition of the external additive to the toner base particles include a Henschel mixer, a Redige mixer, and a TURBO SPHERE mixer. Among them, the Henschel mixer can be suitably used from the viewpoints of being able to perform mixing and fixing of the external additive in the same apparatus, and easy stirring and mixing and easy heating from the outside. ,preferable.
In the step of externally adding a fatty acid metal salt having an average particle diameter of 2 to 4 μm and resin particles having an average particle diameter of 180 nm to 320 nm to the toner base particles to obtain an externally added toner, the peripheral speed at the tip of the stirring blade is 10 to 30 m. It is preferable to process at / s, and it is more preferable to process at 15 to 38 m / s. Next, in the step of externally adding an external additive having an average particle size of less than 180 nm to the external additive toner, it is necessary to make the external additive adhere more strongly than the two external additives. It is preferable to process at -55 m / s, and it is more preferable to process at 42-50 m / s. It can control easily in the range of turbidity 35-60 as it is the said range.

<Electrostatic image developer>
The electrostatic image developing toner of the present invention is used as it is as a one-component developer or as a two-component developer. When used as a two-component developer, it is used by mixing with a carrier.

  There is no restriction | limiting in particular as a carrier which can be used for a two-component developer, A well-known carrier can be used. Examples thereof include magnetic metals such as iron oxide, nickel, and cobalt, magnetic oxides such as ferrite and magnetite, resin-coated carriers having a resin coating layer on the surface of the core material, and magnetic dispersion carriers. Further, a resin-dispersed carrier in which a conductive material or the like is dispersed in a matrix resin may be used.

  Coating resins and matrix resins used for carriers include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic. Examples include acid copolymers, straight silicone resins composed of organosiloxane bonds or modified products thereof, fluororesins such as perfluoroacrylate copolymers, polyester resins, polycarbonate resins, phenol resins, and epoxy resins. It is not limited to.

  Examples of the conductive material include metals such as gold, silver and copper, carbon black, titanium oxide, zinc oxide, barium sulfate, aluminum borate, potassium titanate, tin oxide, and carbon black. It is not limited.

Examples of the carrier core material include magnetic metals such as iron, nickel, and cobalt, magnetic oxides such as ferrite and magnetite, and glass beads. However, in order to use the carrier for the magnetic brush method, a magnetic material is used. Preferably there is.
The volume average particle size of the core material of the carrier is preferably in the range of 10 μm to 500 μm, and more preferably in the range of 30 μm to 100 μm.

In order to coat the surface of the carrier core material with a resin, there may be mentioned a method of coating with a coating layer forming solution obtained by dissolving the coating resin and, if necessary, various additives in an appropriate solvent.
The solvent is not particularly limited and may be appropriately selected in consideration of the coating resin to be used, coating suitability, and the like.

  Specific resin coating methods include an immersion method in which the carrier core material is immersed in the coating layer forming solution, a spray method in which the coating layer forming solution is sprayed onto the surface of the carrier core material, and the carrier core material is fluidized air. A fluidized bed method in which the coating layer forming solution is sprayed in a state of being suspended by the above, a kneader coater method in which the carrier core material and the coating layer forming solution are mixed in a kneader coater, and the solvent is removed.

  The mixing ratio (weight ratio) between the toner of this embodiment and the carrier in the two-component developer is preferably in the range of toner: carrier = 1: 100 or more and 30: 100 or less, and 3: 100 or more and 20 or more. : More preferably in the range of 100 or less.

<Image Forming Method and Image Forming Apparatus>
The image forming method of the present invention includes a latent image forming step of forming an electrostatic latent image on the surface of the latent image holding member, and developing the electrostatic latent image formed on the surface of the latent image holding member with a developer containing toner. A developing step for forming a toner image, a transfer step for transferring the toner image formed on the surface of the latent image holding member to the surface of the transfer target, a fixing step for fixing the toner image transferred on the surface of the transfer target, and And a step of cleaning the toner remaining on the latent image holding member with a cleaning blade in contact with the latent image holding member, and the developer is the electrostatic charge image developing toner of the invention or the static toner of the invention. It is preferable to use a charge image developer.
The image forming apparatus of the present invention forms a latent image on the latent image holding body by exposing the latent image holding body, charging means for charging the latent image holding body, and exposing the charged latent image holding body. Exposure means for developing, developing means for developing the electrostatic latent image with a developer to form a toner image, transfer means for transferring the toner image from the latent image holding member to the surface of the transfer target, and the transfer target A fixing unit that fixes the toner image transferred to the surface of the body, and a cleaning blade that is in contact with the latent image holding member, and the developer of the electrostatic image of the present invention or the present invention as the developer; It is preferable to use an electrostatic charge image developer.

In this image forming method, for example, the portion including the developing unit may have a cartridge structure (process cartridge) that is detachable from the main body of the image forming apparatus.
The process cartridge of the present invention is preferably a process cartridge including a developer holder and containing the electrostatic image developing toner of the present invention or the electrostatic image developer of the present invention.
Hereinafter, although an example of the image forming apparatus of the present invention will be described as an embodiment, the present invention is not 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. 4 image forming units 10Y, 10M, 10C, and 10K (image forming means). These image forming units (hereinafter also simply referred to as “units”) 10Y, 10M, 10C, and 10K are arranged in parallel in the horizontal direction with a predetermined distance therebetween. 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. The vehicle travels in the direction toward the unit 10K. A force is applied to the support roller 24 in a direction 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 both.
Further, an intermediate transfer member cleaning device 30 is provided on the side of the image carrier of the intermediate transfer belt 20 so as to face the driving roller 22.
Further, each of the developing devices (developing means) 4Y, 4M, 4C, and 4K of the units 10Y, 10M, 10C, and 10K has 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, a first image that forms a yellow image disposed on the upstream side in the intermediate transfer belt traveling direction is formed. The unit 10Y will be described as a representative. It should be noted that reference numerals with magenta (M), cyan (C), and black (K) are attached to the same parts as those of the first unit 10Y instead of yellow (Y). Description of the units 10M, 10C, and 10K will be omitted.

The first unit 10Y has a photosensitive member (latent image holding member) 1Y that functions as an 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 latent 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 6 μm and containing at least a yellow colorant and a polyester resin is stored. 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 electric 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 photoreceptor 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

  The intermediate transfer belt 20 onto which the four color toner images have been transferred in multiple passes through the first to fourth units is disposed on the image transfer surface side of the intermediate transfer belt 20, the support roller 24 that contacts the inner surface of the intermediate transfer belt 20, and 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. The secondary transfer bias at this time is determined according to the resistance detected by a resistance detection 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.

Examples of the transfer target to which the toner image is transferred include plain paper and OHP sheet used for electrophotographic copying machines, printers, and the like.
In order to further improve the smoothness of the image surface after fixing, it is preferable that the surface of the transfer object is as smooth as possible. Art paper or the like can be suitably used.

In addition, it is preferable that the image glossiness (75 °) after fixing a single color image composed of cyan, magenta, and yellow having an image area ratio of 100% is 50% or more. In a full-color image, it is desirable that the image gloss is high from the viewpoint of color development and photographic image quality reproducibility. When using highly glossy paper such as coated paper for higher image quality, if the image gloss is significantly lower than the gloss of the paper, it will appear visually dark. High gloss is more preferable.
For example, when fixing is performed using coated paper such as coated paper having a glossiness (75 °) of 50% or more, the image glossiness after fixing is preferably 50% or more, and more preferably 60% or more. The measurement can be performed based on JIS Z 8741.

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.

FIG. 2 is a schematic configuration diagram showing a preferred embodiment of a process cartridge containing the electrostatic charge image developer of the present invention.
In the process cartridge 200, the charging roller 108, the developing device 111, the photosensitive member cleaning device 113, the opening 118 for exposure, and the opening 117 for static elimination exposure are mounted on the mounting rail 116 together with the photosensitive member 107. Combined and integrated.
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.

  The process cartridge 200 shown in FIG. 2 includes a charging roller 108, a developing device 111, a photoconductor cleaning device 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. It is possible to combine them selectively. Further, in the process cartridge of this embodiment, in addition to the photosensitive member 107, the charging roller 108, the developing device 111, the photosensitive member cleaning device (cleaning means) 113, the opening 118 for exposure, and the discharge exposure. At least one selected from the group consisting of the openings 117.

Next, the toner cartridge of the present invention will be described.
The toner cartridge of the present invention is detachably attached to the image forming apparatus, and at least in the toner cartridge that stores toner to be supplied to the developing means provided in the image forming apparatus, the toner is the toner of the present invention. It is characterized by being. Note that the toner cartridge of the present invention only needs to contain at least toner, and may contain developer, for example, 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 in which the container is miniaturized by using the toner cartridge containing the toner according to the embodiment. This makes it 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.

EXAMPLES Hereinafter, although an Example and a comparative example are given and embodiment of this invention is described in detail in detail, this invention is not limited to a following example.
In the following description, “parts” means “parts by weight” unless otherwise specified.

〔Measuring method〕
<Measurement method of volume average particle diameter (when the particle diameter to be measured is 2 μm or more)>
When the diameter of the particle to be measured was 2 μm or more, the volume average particle diameter of the particle was measured using a Coulter Multisizer II type (manufactured by Beckman-Coulter). As the electrolytic solution, ISOTON-II (manufactured by Beckman-Coulter) was used.

  As a measurement method, 0.5 mg of a measurement sample was added to 2 ml of a 5% aqueous solution of a surfactant (sodium dodecylbenzenesulfonate) as a dispersant, and this was added to 100 ml of the electrolytic solution. The electrolytic solution in which the measurement sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute, and the particle size is 2.0 to 2.0 using the Coulter Multisizer-II aperture with an aperture diameter of 100 μm. The particle size distribution of particles in the range of 60 μm was measured. The number of particles measured is 50,000.

  For the measured particle size distribution, a cumulative distribution was drawn from the smaller diameter side with respect to the divided particle size range (channel), and the particle size at 50% cumulative was defined as the volume average particle size.

<Measurement method of volume average particle diameter (when particle diameter to be measured is less than 2 μm)>
When the particle diameter to be measured was less than 2 μm, the volume average particle diameter of the particles was measured using a laser diffraction particle size distribution analyzer (LS13320: manufactured by Beckman-Coulter).

  As a measurement method, a sample in a dispersion state is adjusted by adding ion exchange water so that the solid content is about 10%, and this is put into a cell until an appropriate concentration is obtained. When the intensity was sufficient to measure, it was measured.

  The volume average particle diameter of each obtained channel was accumulated from the smaller volume average particle diameter, and the volume average particle diameter was determined to be 50%.

<Calculation of average circularity>
The average circularity of the toner base particles is obtained by performing image analysis on at least 5,000 or more toner base particles or toners using Sysmex FPIA-2100. The equivalent circle diameter is the same from the area of the two-dimensional image. The diameter of a circle having an area of 5 mm was obtained, and the circularity was calculated from the following formula, and the average circularity was obtained by statistical processing.
Circularity = circle equivalent diameter perimeter / perimeter = [2 × (Aπ) ^1/2 ] / PM
(In the above formula, A represents the projected area and PM represents the perimeter.)
In addition, HPF mode (high resolution mode) was used for the measurement, and the dilution factor was 1.0. In analyzing the data, the number particle size analysis range was set to 2.0 to 30.1 μm and the circularity analysis range was selected to be 0.40 to 1.00 for the purpose of removing measurement noise.

<Measuring method of melting point and glass transition temperature>
The glass transition temperature (Tg) and the melting point are measured from 0 ° C. to 150 ° C. under a temperature rising rate of 10 ° C./min using a differential scanning calorimeter (manufactured by Mac Science: DSC3110, thermal analysis system 001). As a result, a DSC spectrum was obtained.

<Measurement of weight average molecular weight (Mw)>
The weight average molecular weight (Mw) (polystyrene conversion) of the polyester resin was measured using GPC (Tosoh Co., Ltd .: HLC-8120 made). The column was TSKgel SuperHM-M (15 cm) manufactured by Tosoh Corporation, and the GPC spectrum was measured with a tetrahydrofuran (THF) solvent. The molecular weight of the polyester resin was calculated using a molecular weight calibration curve created with a monodisperse polystyrene standard sample.

<Measurement of acid value>
The acid value was measured according to JIS K0070 and using a neutralization titration method. That is, an appropriate amount of a sample is taken, 100 ml of a solvent (diethyl ether / ethanol mixed solution) and a few drops of an indicator (phenolphthalein solution) are added, and the mixture is thoroughly shaken on a water bath until the sample is completely dissolved. This was titrated with a 0.1 mol / l potassium hydroxide ethanol solution, and the end point was when the indicator was light red for 30 seconds. Acid value is A (mg KOH / g), sample amount is S (g), 0.1 mol / l potassium hydroxide ethanol solution used for titration is B (ml), f is 0.1 mol / l potassium hydroxide ethanol solution A = (B × f × 5.611) / S.

<Measurement of conductivity>
The conductivity of the toner dispersion filtrate was measured at 25 ° C. using a conductivity meter CM-30S manufactured by Toa Denpa Kogyo Co., Ltd.

<PH measurement>
To measure the pH of the toner dispersion filtrate, a pH meter (HM-26S) manufactured by Toa Denpa Kogyo Co., Ltd. was used at 25 ° C.

(Synthesis of non-crystalline polyester resin (1))
In a heat-dried two-necked flask, 80 mol parts of polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene (2,2) -2,2-bis (4 -Hydroxyphenyl) propane 20 mol part, terephthalic acid 50 mol part, fumaric acid 25 mol part, n-dodecenyl succinic acid 25 mol part as raw materials, dibutyltin oxide is put as a catalyst, nitrogen gas is introduced into the container After maintaining the temperature in an inert atmosphere and raising the temperature, a copolycondensation reaction was performed at 150 to 230 ° C. for about 12 hours, and then the pressure was gradually reduced at 210 to 250 ° C. to synthesize an amorphous polyester resin (1).

  The weight average molecular weight (Mw) of the obtained amorphous polyester resin (1) was 18,100. The acid value of the amorphous polyester resin (1) was 13.9 mgKOH / g.

Furthermore, the melting point of the non-crystalline polyester resin (1) was measured using a differential scanning calorimeter (DSC) and analyzed according to JIS standards (see JIS K-7121).
As a result, a stepwise endothermic change was observed without showing a clear peak. The glass transition temperature (Tg) at the midpoint of the stepwise endothermic change was 62 ° C.

(Synthesis of non-crystalline polyester resin (2))
To a heat-dried two-necked flask, 10 mol parts of polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane and polyoxypropylene (2,2) -2,2-bis (4 -Non-crystalline polyester except that 40 mol parts of hydroxyphenyl) propane, 50 mol parts of terephthalic acid, 40 mol parts of dodecenyl succinic acid and 10 mol parts of 1,2,4-benzenetricarboxylic acid (trimellitic acid) The amorphous polyester resin (2) was synthesized in the same manner as the resin (1).

When the molecular weight was measured in the same manner as in the amorphous polyester resin (1), the weight average molecular weight (Mw) of the obtained amorphous polyester resin (2) was 32,600.
The acid value of the amorphous polyester resin (2) was 16.9 mgKOH / g.

  When the melting point measurement was performed in the same manner as in the non-crystalline polyester resin (1) and the DSC spectrum was obtained, no clear peak was shown, and a step-like endothermic change was observed. The glass transition temperature (Tg) at the midpoint of the stepwise endothermic change was 60 ° C.

(Synthesis of crystalline polyester resin)
To a heat-dried three-necked flask, 43.4 parts by weight of 1,10-dodecanedioic acid, 32.8 parts by weight of 1,9-nonanediol, 27 parts by weight of dimethyl sulfoxide, and 0.03 weight of dibutyltin oxide as a catalyst After that, the air in the container was brought into an inert atmosphere with nitrogen gas by a depressurization operation, and stirred at 180 ° C. for 4 hours by mechanical stirring. Dimethyl sulfoxide was distilled off under reduced pressure, and then the temperature was gradually raised to 220 ° C. under reduced pressure and stirred for 1.5 hours. When it became viscous, it was air-cooled to stop the reaction, and aliphatic. A crystalline polyester resin (1) was synthesized.

When the molecular weight was measured in the same manner as in the amorphous polyester resin (1), the weight average molecular weight (Mw) of the obtained aliphatic crystalline polyester resin was 23,000.
Further, the melting point measurement was performed in the same manner as in the non-crystalline polyester resin (1), and the DSC spectrum was obtained. The aliphatic crystalline polyester resin had a clear peak, and the melting point (Tm1) was 78 ° C. .

<Preparation of resin particle dispersion>
(Non-crystalline polyester resin particle dispersion (1))
After adding 175 parts of methyl ethyl ketone and 70 parts of isopropanol to a separable flask equipped with a stirrer and a thermometer to make a mixed solvent, 350 parts of amorphous polyester resin (1) was gradually added and stirred with a three-one motor. Then, the mixture was heated to 40 ° C. and completely dissolved to obtain an oil phase. To this stirred oil phase, 9.6 parts of a 10% NH 4 OH aqueous solution was dropped, and ion-exchanged water was further dropped for phase inversion emulsification. Subsequently, the solvent was removed while reducing the pressure with an evaporator to obtain an amorphous polyester resin particle dispersion (1). The volume average particle diameter of the resin particles was 168 nm. The resin particle concentration was adjusted to 30% with ion exchange water.

(Non-crystalline polyester resin particle dispersion (2))
An amorphous polyester resin particle dispersion (2) was obtained in the same manner as the amorphous polyester resin particle dispersion (1). The volume average particle diameter of the resin particles in the non-crystalline polyester resin particle dispersion (2) is 164 nm, and the resin particle concentration is 30 by adjusting with ion-exchanged water as in the non-crystalline polyester resin particle dispersion (1). %.

(Crystalline polyester resin particle dispersion (1))
In a separable flask equipped with a stirrer and a thermometer, 180 parts of methyl ethyl ketone and 45 parts of isopropanol were added to make a mixed solvent, and then 300 parts of crystalline polyester resin (1) was gradually added, while stirring with a three-one motor. It was completely dissolved while heating to 70 ° C. to obtain an oil phase. To this stirred oil phase, 14 parts of a 10% NH ₄ OH aqueous solution was added dropwise, and ion-exchanged water was further added to emulsify the phase. Subsequently, the solvent was removed while the pressure was reduced with an evaporator to obtain a crystalline polyester resin particle dispersion (1).

  The volume average particle diameter of the resin particles in the crystalline polyester resin particle dispersion (1) was 171 nm, and the resin particle concentration was adjusted to 25% with ion-exchanged water.

(Styrene-butyl acrylate resin particle dispersion (1))
-Styrene: 370 parts-n-Butyl acrylate: 30 parts-Acrylic acid: 4 parts-Dodecanethiol: 24 parts-Carbon tetrabromide: 4 parts Dispersed in a flask in 6 parts of Sanyo Chemical Industries, Ltd .: Nonipol 400) and 10 parts of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) dissolved in 560 parts of ion-exchanged water. 50 ml of ion-exchanged water in which 4 parts of ammonium persulfate was dissolved was added to the mixture while slowly mixing for 10 minutes. After nitrogen substitution, the contents were kept at 70 ° C. while stirring the flask. The mixture was heated in an oil bath until it became, and emulsion polymerization was continued for 5 hours. Thus, a styrene-butyl acrylate resin particle dispersion (1) (resin particle concentration: obtained by dispersing resin particles having an average particle diameter of 165 nm, a glass transition temperature of 58 ° C., and a weight average molecular weight (Mw) of 14,000. 40% by weight) was prepared.

(Styrene-butyl acrylate resin particle dispersion (2))
-Styrene: 280 parts-n-Butyl acrylate: 120 parts-Acrylic acid: 8 parts A solution obtained by mixing and dissolving the above components was mixed with 6 parts of a nonionic surfactant (Nonipol 400), an anionic surfactant (Neogen SC) ) Add 12 parts to a solution dissolved in 550 parts of ion-exchanged water, disperse in a flask for 10 minutes to emulsify, and while mixing slowly, add 50 parts of ion-exchanged water in which 3 parts of ammonium persulfate is dissolved, Nitrogen replacement was performed. Thereafter, the flask was heated with an oil bath while stirring until the content reached 70 ° C., and emulsion polymerization was continued for 5 hours. As a result, a styrene-butyl acrylate resin particle dispersion (2) (resin particle concentration: 40% by weight) having a center diameter of 112 nm, a glass transition temperature of 54 ° C., and a weight average molecular weight (Mw) of 560,000 was prepared.

(Partition agent particle dispersion)
Paraffin wax (Nippon Seiwa Co., Ltd., HNP-9, melting point: 75 ° C.): 50 parts Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 0.5 parts Exchanged water: 200 parts or more were mixed, heated to 95 ° C., and dispersed using a homogenizer (manufactured by IKA, Ultra Turrax T50). Thereafter, dispersion treatment was performed with a Manton Gorin high-pressure homogenizer (Gorin) to prepare a release agent particle dispersion (solid content concentration: 30%) in which the release agent was dispersed. The volume average particle size of the release agent was 0.24 μm.

(Colorant particle dispersion)
・ 1,000 parts of cyan pigment (manufactured by Dainichi Seika Kogyo Co., Ltd., Pigment Blue 15: 3 (copper phthalocyanine)) 15 parts of anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen R) More than 9,000 parts of water are mixed, dissolved, and dispersed for about 1 hour using a high-pressure impact disperser Ultimateizer (manufactured by Sugino Machine, HJP30006) to disperse the colorant (cyan pigment). A colorant dispersion was prepared. The volume average particle size of the colorant (cyan pigment) in the colorant dispersion was 0.16 μm, and the solid content concentration was 25%.

(Production of toner mother particles (1))
Non-crystalline polyester resin particle dispersion (1) 177 parts Non-crystalline polyester resin particle dispersion (2) 177 parts Colorant particle dispersion 59 parts Release agent particle dispersion 40 parts Anionic surface activity 14 parts (TeicaPower BN2060 20% aqueous solution manufactured by Teika Co., Ltd.)

-Emulsification process-
The raw material was placed in a cylindrical stainless steel container, and the homogenizer (Ultra Larax T50, manufactured by IKA) was used. The homogenizer was rotated at 4,000 rpm and dispersed and mixed for 10 minutes while applying a shearing force. Next, after adding a 0.3N nitric acid aqueous solution until the pH of the above mixture becomes 4.8, 12.5 parts of a 10% nitric acid aqueous solution of aluminum sulfate as an aggregating agent, 30% aqueous solution of ethylenediaminetetraacetic acid (EDTA) 12% The portion was gradually added dropwise, and the homogenizer rotation speed was set to 5,000 rpm and dispersed and mixed for 15 minutes to obtain a raw material dispersion.

-Aggregation process-
Thereafter, the raw material dispersion was transferred to a polymerization kettle equipped with a stirrer and a thermometer and started to be heated with a mantle heater to promote the growth of aggregated particles at 42 ° C. At this time, the pH of the raw material dispersion was adjusted to a range of 3.2 or more and 3.8 or less using 0.3N nitric acid or 1N sodium hydroxide aqueous solution. The raw material dispersion was kept in the above pH range and allowed to stand for about 2 hours to form aggregated particles. The volume average particle diameter of the aggregated particles was 5.3 μm.

  Next, 280 parts of an amorphous polyester resin dispersion liquid (1) and 3.5 parts of an anionic surfactant (TeycaPower BN2060 20% aqueous solution) are additionally added to the raw material dispersion liquid. The resin particles of the polyester resin (1) were adhered and held for 10 minutes, and it was confirmed with an optical microscope that the amorphous polyester resin particles adhered to the aggregated particles. Next, the temperature of the raw material dispersion was raised to 44 ° C., and aggregated particles were prepared using an optical microscope and Coulter Multisizer II while confirming the size and form of the particles.

-Fusion process-
Thereafter, in order to fuse the aggregated particles, an aqueous NaOH solution was added dropwise to the raw material dispersion to adjust the pH to 7.5, and then the raw material dispersion was heated to 95 ° C. Thereafter, the raw material dispersion was allowed to stand for 2 hours and 30 minutes to fuse the aggregated particles. After confirming that the aggregated particles were fused with an optical microscope, the raw material dispersion was cooled at a temperature decrease rate of 1.0 ° C./min.

-Washing process-
[Step of washing with treatment liquid of pH 9 or more and pH 10 or less]
Thereafter, using 0.3N nitric acid or 1N sodium hydroxide aqueous solution, the pH of the raw material dispersion was adjusted to 9.5 at 25 ° C., stirred for 20 minutes, and sieved with a mesh having a pore diameter of 20 μm. Next, the raw material dispersion was filtered. The toner after solid-liquid separation was dispersed in ion exchange water at 30 ° C., 15 times the solid amount of the toner, and filtered by stirring for 20 minutes.
After repeating this process twice, it was confirmed that the filtrate had a conductivity of 38 μS.

[Step of washing with ion exchange water at least 20 times the solid amount of toner]
Next, the toner and the dispersion medium were solid-liquid separated from the toner dispersion by suction filtration. After that, the toner was dispersed in ion exchange water having a 10 times amount water temperature of 30 ° C. and stirred with a mechanical stirrer. When the solid content of the toner on the cake hardened by suction filtration was uniformly dispersed in ion-exchanged water, it was separated into solid and liquid by suction filtration again. This process was repeated again and filtration was performed. The conductivity of the filtrate was confirmed to be 19 μS.

-Toner drying-
After finishing the washing process, the toner mother particles (1) were obtained by drying with a freeze vacuum dryer.
The obtained toner base particles (1) had a volume average particle diameter of 5.9 μm. The average circularity was 0.952.

(Production of toner mother particles (2))
In the fusing step in the production process of the toner base particles (1), the temperature of the raw material dispersion is raised to 95 ° C., and then the time for standing at 95 ° C. for fusing is changed to 3 hours. ) To obtain toner base particles (2). Toner base particles (2) had a volume average particle size of 5.7 μm and an average circularity of 0.985.

(Production of toner mother particles (3))
Toner base particles (3) were obtained in the same manner as toner base particles (1) except that 60 parts of the crystalline polyester resin particle dispersion was added in the production process of toner base particles (1). Toner mother particles (3) had a volume average particle diameter of 5.8 μm and an average circularity of 0.972.

(Production of toner mother particles (4))
Toner mother particles (4) were obtained in the same manner as in Example 1, except that 132 parts of the crystalline polyester resin particle dispersion was added in the production process of the toner mother particles (1). Toner mother particles (3) had a volume average particle diameter of 5.7 μm and an average circularity of 0.979.

(Production of toner base particles (5))
-Styrene-butyl acrylate resin particle dispersion (1) 158 parts-Styrene-butyl acrylate resin particle dispersion (2) 105 parts-Colorant particle dispersion 59 parts-Release agent particle dispersion 40 parts-Cationic surfactant Agent (Sanisol B50) 2.0 parts The above raw materials are placed in a cylindrical stainless steel container, and using a homogenizer (IKA, Ultra Turrax T50), the homogenizer rotation speed is set to 4,000 rpm and a shearing force is applied for 10 minutes. Dispersed and mixed. Next, after adding a 0.3N nitric acid aqueous solution until the pH of the above mixture becomes 4.8, 13 parts of a 10% nitric acid aqueous solution of aluminum sulfate as a flocculant is dropped, and the rotation speed of the homogenizer is set to 5,000 rpm. And dispersed for 5 minutes to obtain a raw material dispersion.
Thereafter, the raw material dispersion was transferred to a polymerization kettle equipped with a stirrer and a thermometer, and started to be heated with a mantle heater, and heated to 54 ° C. with stirring to promote the growth of aggregated particles. At this time, the pH of the raw material dispersion was adjusted to 3.8 or more and 4.2 or less using 0.3N nitric acid or 1N sodium hydroxide aqueous solution. After maintaining at 54 ° C. for 1 hour, the average particle size was measured with a Coulter counter (manufactured by Beckman-Coulter, Inc .: Multisizer II). As a result, aggregated particles of 4.9 μm were produced. When the temperature was further raised and held at 55 ° C. for 1 hour, the average particle size of the aggregated particles was 5.3 μm.

  To the dispersion containing the aggregate particles, 82 parts by weight of the styrene-butyl acrylate resin particle dispersion (1) was gently added, and the temperature of the heating oil bath was raised and maintained at 56 ° C. for 1 hour. When the average particle diameter of the obtained adhered particles was measured, it was 5.5 μm. After adding 3 parts by weight of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen SC) to the adhering particle dispersion, the stainless steel flask was sealed, and stirring was continued using a magnetic seal at 97 ° C. And heated for 4 hours. After aggregating the aggregated particles and confirming the aggregation of the aggregated particles with an optical microscope, the aggregated particles were cooled at a temperature drop rate of 10 ° C./min, and washed and dried in the same manner as toner base particles (1). (5) was obtained. The obtained volume average particle diameter was 5.6 m, and the average circularity was 0.967.

(Production of toner mother particles (6))
In the fusing step in the production process of the toner mother particles (1), the temperature of the raw material dispersion was raised to 95 ° C., and then the time allowed to stand at 95 ° C. for fusing was changed to 2 hours. In the same manner as in 1), toner mother particles (6) were obtained. Toner base particles (6) had a volume average particle size of 6.1 μm and an average circularity of 0.948.

(Production of toner mother particles (7))
In the fusion step in the production process of the toner mother particles (3), the temperature of the raw material dispersion was raised to 95 ° C., and then the time allowed to stand at 95 ° C. for fusion was changed to 3 hours and 15 minutes. Toner mother particles (7) were obtained in the same manner as particles (3). Toner base particles (7) had a volume average particle size of 5.7 μm and an average circularity of 0.992.

(Career)
Ferrite particles (average particle size: 35 μm) 100 parts Toluene 14 parts Perfluoroacrylate copolymer (manufactured by Sanyo Chemical Industries, Ltd., critical surface tension 24 mN / m) 1.6 parts Carbon black (manufactured by Cabot Corporation) "VXC-72", resistance 100Ωcm or less)
0.12 parts cross-linked melamine resin particles (average particle size; 0.3 μm, toluene insoluble) 0.3 parts Carbon black diluted with toluene and dispersed in a perfluoroacrylate copolymer using a sand mill, Furthermore, it stirred with the stirrer for 10 minutes and prepared the film layer forming liquid. Next, this coating layer forming solution and ferrite particles are put into a vacuum degassing type kneader and stirred at a temperature of 60 ° C. for 30 minutes, and then the pressure is reduced to distill off toluene, thereby forming a resin coating layer and carrier. Obtained.

-Examples 1-7 and Comparative Examples 1-11-
<External Addition>
With respect to 100 parts of each of the obtained toner base particles (1) to (7), the external additives [1] to [5] below are added in the amounts and conditions shown in Table 1 below. The mixture was mixed with a Henschel mixer, and further passed through a Resona sieve (manufactured by Tokuju Kogyo Co., Ltd.) and sieved to obtain electrostatic image developing toners.
[1] Silica particles having a primary particle size of 40 nm subjected to surface hydrophobization (Nippon Aerosil Co., Ltd., hydrophobic silica: RX50)
[2] Metatitanic acid compound particles having an average primary particle diameter of 20 nm, which is a reaction product obtained by treating 100 parts of metatitanic acid with isobutyltrimethoxysilane [3] Large silica particles having a primary particle diameter of 130 nm prepared by a sol-gel method [4] Zinc stearate particles (StZn particles)
[5] Polymethyl methacrylate particles (PMMA particles)

<Evaluation of toner>
(Measure turbidity and confirm the presence or absence of fatty acid metal salts and resin particles)
Each toner (5.0 g) was dispersed in 100 ml of an aqueous solution containing 1 ml of a nonionic surfactant (Neugen EA137 (Daiichi Kogyo Seiyaku Co., Ltd.)), placed on an ultrasonic shaker for 3 minutes, and then centrifuged (2 , 000 rpm: 20 minutes) and collect the supernatant. Using this, COH-400 manufactured by Nippon Denshoku Industries Co., Ltd. was used to calculate the ratio of the diffusing component of the total transmitted component with respect to the incident light (HAZE value (haze value)). did.
Haze value (HAZE value) = 100 × (diffuse component of total transmission component) / (total transmission component)
Moreover, the presence or absence of the fatty acid metal salt and the resin particles was confirmed by the following method.
That is, the supernatant obtained by further centrifuging the supernatant with a centrifugal separator at 10,000 rpm for 5 minutes was subjected to volume average of the dispersion using a laser diffraction particle size distribution analyzer (LS13320: manufactured by Beckman Coulter, Inc.). The particle size was measured and judged from the particle size distribution and an electron microscope image of the dried dispersion.

(Image quality and cleanability)
Two parts of the obtained electrostatic charge image developing toner and 100 parts by weight of a resin-coated ferrite carrier (average particle size 35 μm) are mixed to prepare a two-component developer, and the obtained developer is respectively DocuPrint. C2220 (Fuji Xerox Co., Ltd.) developer was filled and seasoned for 24 hours in a low-temperature, low-humidity environment (10 ° C./15% RH).
Next, each developer was filled in a developer of DocuPrint C2220 (Fuji Xerox Co., Ltd.) and seasoned for 24 hours in an environment of high temperature and high humidity (28 ° C./85% RH).
After the above, each developing device is mounted on an actual machine, and a rectangular component having a DC component of −500 V as an 30,000 copy test developing bias, an AC superimposition component of Vp-p 1.5 kV, and a frequency of 6 kHz for an image with an image area ratio of 5%. A wave superimposed was applied to the developing sleeve and a print test was performed. Cleaning was performed by pressing a urethane rubber blade against the surface of the photoreceptor.
On the other hand, in parallel with the evaluation of the cleaning performance, secondary obstacles such as copy image quality and cleaning blade wear during the copying test were visually evaluated.

(Low temperature fixability)
Each of the obtained developers was filled in a developing device of DocuPrint C2220 (Fuji Xerox Co., Ltd.) from which the fixing device was removed, and unfixed images were collected. The image conditions were a solid image of 40 mm × 50 mm, the toner amount was 1.5 mg / cm ² , and the recording paper was mirror-coated platinum paper (basis weight: 127 gsm). Subsequently, the fixing device of DocuPrint C2220 was modified so that the fixing temperature was variable, and the low-temperature fixing property of the image was evaluated while the fixing temperature was increased stepwise from 100 ° C. to 220 ° C. Note that low temperature fixability is achieved by bending a good fixed image with a certain load weight without image loss due to defective mold release, and then marking the degree of image loss at that portion, and fixing temperature that exceeds a certain grade. The lowest fixing temperature was used as an index for low-temperature fixability. The minimum fixing temperature is preferably 120 ° C. or lower.

Table 2 shows the evaluation results of the evaluations in Examples 1 to 7 and Comparative Examples 1 to 11.
The overall evaluation is based on comprehensive evaluation of each evaluation of cleaning performance, image quality, and low-temperature fixability, and ◎ indicates that each performance is particularly excellent, ○ indicates that each performance is excellent, and ○ indicates practical performance. The problem level was evaluated as x.

  As can be seen from Table 2, since the polyester resin is used in the examples, the low-temperature fixability is excellent, and the effect is greater when the crystalline polyester resin is included. In addition, the toner shape effect and the particle size balance between the fatty acid metal salt and the resin particles have a synergistic effect, and continuously provide good cleaning properties in cleaning using a blade, and repeatedly provide excellent images. I was able to.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus of the present invention. It is a schematic block diagram which shows an example of the process cartridge of this invention.

Explanation of symbols

1Y, 1M, 1C, 1K, 107: photoconductor (latent image holder)
2Y, 2M, 2C, 2K, 108: charging roller 3Y, 3M, 3C, 3K: laser beam 3, 110: exposure device 4Y, 4M, 4C, 4K, 111: developing device (developing means)
5Y, 5M, 5C, 5K: primary transfer roller (primary transfer means)
6Y, 6M, 6C, 6K, 113: Photoconductor cleaning device (cleaning means, blade cleaning)
8Y, 8M, 8C, 8K: toner cartridges 10Y, 10M, 10C, 10K: unit 20: intermediate transfer belt 22: drive roller 24: support roller 26: secondary transfer roller (secondary transfer means)
28, 115: fixing device (fixing means)
30: Intermediate transfer member cleaning device 112: Transfer device 116: Mounting rail 117: Opening portion 118 for static elimination exposure: Opening portion 200 for exposure: Process cartridge P: Recording paper (transferred material)

Claims (7)

Including toner base particles including a polyester resin, a colorant and a release agent, and an external additive,
The average circularity of the toner base particles is 0.95 to 0.985,
Turbidity measured under the following conditions is 35-60,
An electrostatic charge image developing toner comprising a fatty acid metal salt having an average particle diameter of 2 to 4 μm and resin particles having an average particle diameter of 180 to 320 nm in a supernatant obtained under the following conditions.
<Turbidity measurement>
Disperse 5.0 g of the electrostatic charge image developing toner in 100 ml of an aqueous solution containing 1 ml of a nonionic surfactant, apply it to an ultrasonic shaker for 3 minutes, then centrifuge at 2,000 rpm for 20 minutes, and remove the supernatant. The sample is collected, and the haze value of the supernatant is measured to determine the turbidity of the electrostatic image developing toner.
The fatty acid metal salt and the resin particles are detected in the supernatant obtained by further centrifuging the supernatant at 10,000 rpm for 5 minutes. A step of aggregating at least the polyester resin particles, the colorant and the release agent in the dispersion to obtain aggregated particles,
A step of heating and aggregating the aggregated particles to obtain toner mother particles;
A step of externally adding a fatty acid metal salt having an average particle size of 2 to 4 μm and resin particles having an average particle size of 180 nm to 320 nm to the toner base particles to obtain an externally added toner; and
The method for producing an electrostatic charge image developing toner according to claim 1, comprising a step of externally adding an external additive having an average particle size of less than 180 nm to the externally added toner.   An electrostatic charge image developer comprising the electrostatic charge image developing toner according to claim 1 or the electrostatic charge image developing toner produced by the production method according to claim 2 and a carrier.   A toner cartridge containing at least the electrostatic image developing toner according to claim 1 or the electrostatic image developing toner produced by the production method according to claim 2. A developer holder,
The electrostatic charge image developing toner according to claim 1, the electrostatic charge image developing toner produced by the production method according to claim 2, or a process cartridge containing the electrostatic charge image developer according to claim 3. . A latent image forming step for forming an electrostatic latent image on the surface of the latent image holding member;
A developing step of forming a toner image by developing the electrostatic latent image formed on the surface of the latent image holding member with a developer containing toner;
A transfer step of transferring the toner image formed on the surface of the latent image holding member to the surface of the transfer target;
A fixing step of fixing the toner image transferred to the surface of the transfer target; and
Cleaning the toner remaining on the latent image holding body with a cleaning blade in contact with the latent image holding body,
The electrostatic charge image developing toner according to claim 1, the electrostatic charge image developing toner produced by the production method according to claim 2, or the electrostatic charge image developer according to claim 3 is used as the developer. Image forming method. A latent image carrier,
Charging means for charging the latent image carrier;
Exposure means for exposing the charged latent image carrier to form an electrostatic latent image on the latent image carrier;
Developing means for developing the electrostatic latent image with a developer to form a toner image;
Transfer means for transferring the toner image from the latent image holding member to the surface of the transfer target;
Fixing means for fixing the toner image transferred to the surface of the transfer target;
A cleaning blade in contact with the latent image holder,
The electrostatic charge image developing toner according to claim 1, the electrostatic charge image developing toner produced by the production method according to claim 2, or the electrostatic charge image developer according to claim 3 is used as the developer. Image forming apparatus.

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