JP2011185973A - Toner for developing electrostatic charge image, image forming apparatus, process cartridge, and developer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner which secures advanced low-temperature fixability, high-temperature storage stability, low staining properties of a photoreceptor, and high-speed printing adaptability, and to provide an image forming apparatus. <P>SOLUTION: The toner contains at least a binder resin, a colorant, a release agent and has a core-shell structure which has a core therein and a shell on a surface of the core. A core portion contains at least a crystalline polyester resin, an amorphous polyester resin, the colorant, and the release agent. A softening temperature ST (°C) of a shell layer, which is measured by an SPM probe incorporating a heater, and a softening temperature CT (°C) of an inner core portion have a relationship 1.1≤ST/CT≤2.5. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

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

  In an electrophotographic apparatus, an electrostatic recording apparatus, etc., toner is attached to an electrostatic latent image formed on a photoreceptor, transferred to a transfer material, and then fixed to a transfer material such as paper by heat. An image is formed. Also, full-color image formation is generally performed by using four color toners of black, yellow, magenta, and cyan. Each toner is developed, and each toner layer is superimposed on a transfer material. To obtain a full-color image.

  However, for users who are familiar with printing and silver halide photography, the images on full-color copiers are still not satisfactory, and there is a need for higher image quality that satisfies photography, high-definition, and high resolution. Yes. Especially when using thick paper or when printing at high speed, the heat quantity during fixing is not sufficiently transmitted, and the image has excellent fixing properties and high image quality (small variations in gloss, density, image sharpness, etc.). Was difficult.

  Furthermore, if such a low-temperature fixing system and toner are extremely advanced, it is possible to manufacture a toner that supports low-temperature fixing by lowering the softening characteristic of the toner, but this time the low-temperature fixing toner has heat-resistant storage characteristics. Is not preferable. In other words, high-temperature and high-humidity and low-temperature and low-humidity environments during storage and transportation after toner production are harsh conditions for the toner, and the toner does not aggregate even after storage in the environment. There is a demand for a toner having no deterioration in fixability or having very little storage stability. On the other hand, in these ultimate low-temperature fixing toners, a filming phenomenon of a photoreceptor in an office high-temperature and high-humidity environment, which has not been a problem in the past, has occurred, and it has been difficult to solve the problem. In other words, the low temperature melt of toner adheres to the surface of the photoconductor, which contaminates the surface of the photoconductor and cannot exhibit its original photosensitivity, resulting in image blurring and the like. It was a very difficult problem because it could not satisfy the needs of output.

In Patent Document 1, a toner material liquid in which a polyester prepolymer having a functional group containing at least a nitrogen atom, a polyester, a colorant, and a release agent having a controlled surface wax amount is dispersed in an organic solvent is used as an aqueous medium. Examples of toner obtained by crosslinking and / or elongation reaction therein are shown. However, the core / shell structure of the toner is not sufficient, and the softening temperature of the core and the softening temperature of the shell layer have not been sufficiently controlled. Therefore, it was a problem in terms of both low-temperature fixability and heat-resistant storage stability.

  As described above, in the conventional toner image system, an image forming apparatus that has both low temperature fixing property, heat resistant storage stability, and low photoreceptor contamination in a high temperature and high humidity environment, particularly in the high-speed printing field where the use conditions are severe. It was difficult to get.

An object of the present invention is to provide the following which solves the above problems.
To provide a toner and an image forming apparatus which ensure high low temperature fixability, heat resistant storage stability, low photoreceptor contamination, and high-speed printing compatibility.

As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that in a toner containing at least a binder resin, a colorant, and a release agent, the toner has a core inside and a thickness of 0. 0 on the surface of the core. A toner having a core-shell structure having a shell of 01 μm to 2 μm, wherein the core portion contains at least a crystalline polyester resin, an amorphous polyester resin, a colorant, a release agent, and a heater built-in SPM probe By using a toner having the following relationship between the softening temperature ST (° C.) of the shell layer and the softening temperature CT (° C.) of the inner core portion measured by the above, a high degree of low-temperature fixing property, heat-resistant storage property, low photosensitivity It has been found that a toner and an image forming apparatus that ensure body contamination and high-speed printing compatibility can be provided.
1.1 ≦ ST / CT ≦ 2.5

(1) In a toner containing at least a binder resin, a colorant, and a release agent, the toner has a core-shell structure having a core inside and a shell on the surface of the core, The softening temperature ST (° C.) of the shell layer, which contains at least a crystalline polyester resin, an amorphous polyester resin, a colorant, a release agent, and is measured by an SPM probe with a built-in heater, and the softening temperature of the inner core portion A toner characterized in that CT (° C.) shows the following relationship.
1.1 ≦ ST / CT ≦ 2.5
(2) The toner according to (1), wherein SL and TL have the following relationship, where SL is the thickness of the shell layer and TL is the maximum diameter of the toner particles.
0.01 ≦ SL / TL ≦ 0.20
(3) The toner according to (1) or (2), wherein the non-crystalline polyester resin contains a modified polyester resin.
(4) The toner is dispersed by dispersing oil droplets of an organic solvent in which a toner composition containing a polyester prepolymer that becomes a crystalline polyester resin, a colorant, a release agent, and an amorphous polyester resin is dispersed in an aqueous medium. The toner according to any one of (1) to (3), wherein the toner is particles formed by a reaction and / or a crosslinking reaction.
(5) The toner according to (4), wherein the polyester prepolymer is a polymer having a site capable of reacting with a compound having an active hydrogen group.
(6) The toner according to (4) or (5), wherein the toner composition further contains an amorphous polyester.
(7) The toner according to any one of (1) to (6), wherein the shell layer of the toner contains at least a vinyl resin.
(8) The toner according to any one of (1) to (7), wherein the toner has an average circularity E of 0.93 to 0.99.
(9) The toner according to any one of (1) to (8), wherein the toner has a circularity SF-1 value of 100 to 150 and a circularity SF-2 value of 100 to 140.
(10) The toner particles have a weight average particle diameter D4 of 2 to 7 μm and a ratio D4 / Dn of the weight average particle diameter D4 to the number average particle diameter Dn of 1.25 or less (1) The toner according to any one of to (9).
(11) A two-component developer comprising at least the toner according to any one of (1) to (10) and a carrier.
(12) A replenishing toner comprising at least the toner according to any one of (1) to (10) and a carrier.
(13) An image forming apparatus using the toner according to any one of (1) to (10).
(14) An image forming apparatus using the toner according to any one of (1) to (10) and including a fixing device that fixes a visible image on a recording medium by heat and pressure, and at least four or more and a tandem type developing system developing color different developing units arranged in series, the system speed is 500~2500mm / sec, and pressing surface pressure of the fixing medium, at 5N / cm ² ~90N / cm ² There is provided a color image forming apparatus.
(15) In a process cartridge that integrally supports the latent image carrier and at least the developing unit and is detachable from the main body of the image forming apparatus, the developing unit holds toner, and the toner is (1) to (10). A process cartridge comprising the toner according to any one of the above.

  According to the present invention, it is possible to provide a toner and an image forming apparatus that have highly secured low-temperature fixability, heat-resistant storage stability, development stability and high-speed printing compatibility.

It is a figure which shows the measuring method of the softening temperature of the shell layer of a toner, and a core part by the SPM probe with a built-in heater. 1 is a schematic diagram illustrating a configuration of an image forming apparatus including a process cartridge of the present invention. 1 is a schematic diagram illustrating a configuration of an example of a tandem color image forming apparatus according to the present invention. It is the schematic which shows the structure of the other example of the tandem type color image forming apparatus of this invention. It is the schematic which shows the structure of the other example of the tandem type color image forming apparatus of this invention. It is the schematic which shows the structure of the other example of the tandem type color image forming apparatus of this invention. FIG. 3 is a view of a cross section of the toner of the present invention observed with a TEM.

  Hereinafter, the present invention will be described in detail. Here, the toner, the manufacturing method and material of the developer, and the overall system relating to the electrophotographic process that are used in the present invention can be used as long as the conditions are satisfied.

The toner of the present invention is a toner having a core-shell structure having a core inside and a shell having a thickness of 0.01 μm to 2 μm on the surface of the core, and at least a crystalline polyester resin and an amorphous polyester in the core portion The softening temperature ST (° C.) of the shell layer measured with an SPM probe containing a resin, a colorant, and a release agent and having a built-in heater and the softening temperature CT (° C.) of the inner core portion have the following relationship: By using the toner shown, it is possible to ensure high low-temperature fixability, heat-resistant storage stability, low photoreceptor contamination, and high-speed printing compatibility.
1.1 ≦ ST / CT ≦ 2.5

The mechanism by which the toner of the present invention exhibits the above-mentioned special effects is currently being elucidated, but the following has been estimated from some analysis data.
The toner of the present invention is a toner having a core-shell structure having a shell having a thickness of 0.01 μm to 2 μm, more preferably 0.4 μm to 1.5 μm on the outside of the toner, and at least a crystalline polyester resin and Contains an amorphous polyester resin, a release agent, and a colorant. Here, the shell layer protects the release agent, the colorant, the low melting component, and the poorly charged component from external factors that adversely affect the charging characteristics inside the toner and the photoreceptor contamination (photoreceptor filming property). When the shell layer thickness is less than 0.01 μm, the effect as a layer is not sufficient, and the photoreceptor contamination and heat-resistant storage stability are unfavorable. On the other hand, if the thickness exceeds 2 μm, the shell layer is too thick, and the color developability due to the colorant inside the core and the bleeding property of the release agent are undesirably lowered. Further, it is not preferable because the low-temperature fixability of the shell layer cannot be sufficiently secured.
In addition, by containing at least a crystalline polyester resin and an amorphous polyester resin as a binder resin in the core, the toner as a whole has a sharp melting characteristic of the crystalline polyester and a plastic effect that is synergistically exhibited with the amorphous polyester. Can be secured at low temperature.

  Furthermore, it is important that the softening temperature ST of the shell layer measured by the SPM probe with a built-in heater and the softening temperature CT of the inner core portion show a relationship of 1.1 ≦ ST / CT ≦ 2.5. By controlling the softening property of the core shell to 1.1 ≦ ST / CT ≦ 2.5, the shell layer prevents melting, sticking, and the like due to the external environment (storage, transportation, various usage conditions). On the other hand, the fixing meltability at the time of image formation fixing at the core is ensured under an appropriate fixing pressure. With the above mechanism, not only low-temperature fixability but also heat-resistant storage stability can be achieved. Here, when ST / CT is less than 1.1, the difference in softening temperature between the shell layer and the core portion is too small, and the original function as protection for toner softening cannot be exhibited. Furthermore, when ST / CT exceeds 2.5, the softening temperature of the shell layer is too high with respect to the softening temperature of the core part, so that low temperature fixability cannot be achieved. Further, when the shell layer is sufficiently softened, the softening temperature of the core portion is too low and does not have sufficient viscosity to fix the toner, and as a result, low temperature fixing cannot be achieved.

The softening temperature ST of the shell layer is preferably 50 ° C to 100 ° C, more preferably 60 ° C to 90 ° C. Moreover, it is preferable that the softening temperature CT of a core part is 40 to 90 degreeC, More preferably, it is 50 to 80 degreeC.

  The shell layer of the toner preferably contains at least a vinyl resin, and among the vinyl resins, a styrene / acryl resin is particularly preferable. The properties due to the surface properties, viscoelasticity, and the like of the vinyl resin are more preferable because the spent resistance of the shell layer at the time of environmental load is remarkably improved.

In addition, it is more preferable that the core portion of the toner contains at least a modified polyester resin, which expands the design range of the thermal characteristics and viscoelastic characteristics of the resin.
Further, the toner is a toner composed of particles formed by dispersing an oil droplet of an organic solvent in which a toner composition containing a prepolymer is dissolved in an aqueous medium, and extending and / or cross-linking. It is possible to form a toner having a core-shell structure, which is more preferable.

  Further, the toner includes a toner composition containing at least a polymer capable of reacting with a compound having an active hydrogen group, a polyester, a colorant, and a release agent in an aqueous medium in the presence of resin fine particles. A toner obtained by an elongation reaction is more preferable because a toner having the core-shell structure can be similarly formed and a toner having an appropriate softening property can be formed inside the shell layer and the core.

In addition, the toner having a mean circularity E of 0.93 to 0.99 is more preferable because it can ensure a core-shell structure with a shape close to a sphere.
In addition, when the toner is a toner having a circularity SF-1 value of 100 to 150 and a circularity SF-2 value of 100 to 140, a core-shell structure can be appropriately secured in a shape close to a spherical shape, which is more preferable. .
The toner has a weight average particle diameter D ₄ of 2 to 7 μm, more preferably 2 to 5 μm, and a ratio D ₄ / Dn of the weight average particle diameter D ₄ to the number average particle diameter Dn of 1.25 or less. More preferably, the toner is 1.15 or less because it is possible to form toner particles having a uniform core-shell structure while ensuring the charge developability, transferability, and fixability of the toner.

In addition, by using a two-component developer containing the toner and a carrier composed of magnetic particles, the charging potential of the toner, which is lowered by the core-shell structure, can be sufficiently increased by frictional charging in a short time. It is more preferable because it can be ensured and a sufficiently sharp charge amount distribution can be maintained.
Further, in an image forming apparatus including a fixing device that fixes a visible image on a recording medium by heat and pressure, the system speed is 500 to 2500 mm / sec, and the pressing surface pressure of the fixing medium is 5 N / cm ² to. In the image forming apparatus of 90 N / cm ² , by using the toner of the present invention, it is possible to meet the demand for low-temperature fixing in high-speed printing, and a sufficiently strong fixing strength even in a situation where the supply fixing heat amount is insufficient. It becomes possible to obtain the possessed image.

(Evaluation of crystallinity)
The presence or absence of crystallinity of the polyester resin in the present invention was evaluated by the presence or absence of the crystallinity peak by X-ray diffraction method. The equipment and conditions are shown below.
XRD: Rigaku Co., Ltd. RINT-TTRIII type wide angle X-ray diffractometer X-ray source; CuKα ray tube voltage-tube current; 50 kV-300 mA
Step width; 0.02 deg.
Measurement range: 2 ° -60 °
Measurement speed: 5 deg. / Min
Slit system; 0.5 deg. -0.15 mm-0.5 deg.
Diffraction line crystal monochromator

(Evaluation of toner core shell structure and shell layer thickness)
The toner of the present invention is a core-shell toner having an inner core and a shell layer on the surface of the core.
In the toner of the present invention, it is preferable that SL and TL have the following relationship, where SL is the thickness of the shell layer and TL is the maximum diameter of the toner particles.
0.01 ≦ SL / TL ≦ 0.20
More preferably, the thickness SL of the shell layer is in the range of 10 nm to 2000 nm, more preferably 50 nm to 1500 nm. The maximum diameter TL of the particles is 2000 nm to 7000 nm, more preferably 3000 nm to 5000 nm.
The present inventors have evaluated the shell layer thickness in correspondence with the maximum particle diameter of the toner, so that there are characteristics that have a significant difference in relation to other characteristics such as toner low-temperature fixability, heat-resistant storage stability, and photoreceptor contamination. It has been found that it can be evaluated as a value.

The thickness of the toner shell layer in the present invention can be evaluated by the following method.
<< Evaluation by TEM (Transmission Electron Microscope) >>
First, the toner is embedded and cured in an epoxy resin about one full spatula. The shell layer and the inside of the core are differentially stained by exposing the sample to gas with ruthenium tetroxide for 5 minutes. An ultra-thin section (200 nm thickness) of the toner is prepared with an ultramicrotome (ULTRACUT UCT manufactured by Leica, using a diamond knife). Thereafter, observation is performed with a TEM (transmission electron microscope; H7000; manufactured by Hitachi High-Tech) at an acceleration voltage of 100 kV.
Image processing analysis of the obtained TEM image is performed to calculate the maximum particle diameter TL and the shell layer thickness SL. One particle is selected at random and the maximum diameter of the particle is determined. Next, the thickness of the shell layer of the particles is determined by randomly selecting five locations. Similarly, other particles are analyzed, and TL and SL are obtained by the average value of a total of 10 particles.

(Evaluation of softening temperature inside shell layer and core by SPM probe with built-in heater)
The evaluation of the softening temperature inside the shell layer and the core by the SPM probe incorporated in the heater of the present invention is preferably performed by the following method, but may be performed as long as it can be evaluated by other means.
As an SPM probe with a built-in heater, a nano-TA unit manufactured by Anasys Instruments Co., Ltd. was used and evaluated by installing it in the SPM. For SPM, a scanning probe microscope manufactured by Veeco; MMMAM type multimode was used. The nano-TA is a method for evaluating the softening characteristics (TMA) and thermal characteristics of a sample using an SPM probe with a built-in heater. The probe (cantilever) is moved to the measurement position of the sample, the tip of the cantilever is heated, and the deflection position of the cantilever is evaluated to evaluate the sinking with respect to the tip temperature (FIG. 1). The inflection point of deflection is evaluated as the softening temperature.

  The nano-TA system can evaluate the softening characteristic (TMA characteristic) of the target location with a resolution of 20 nm using a sensitive dedicated cantilever equivalent to an atomic force microscope. Measurement positioning can be performed in contact mode or tapping mode as a normal atomic force microscope, and the shell layer of the target toner cross section and the softening characteristics inside the core can be individually evaluated. In consideration of measurement variations, it is preferable to evaluate the average softening temperature of the toner 5 particles. The heating rate of the cantilever was 5 ° C./sec. The softening temperature of the apparatus is calibrated using three standard resins whose softening temperatures are known in advance.

(Average circularity E)
The average circularity E of the toner of the present invention is defined by circularity E = (peripheral length of a circle having the same area as the projected particle area / perimeter length of the projected particle image) × 100%. Measurement was performed using a flow type particle image analyzer (“FPIA-2100”; manufactured by Sysmex Corporation), and analysis was performed using analysis software (FPIA-2100 Data Processing Program for FPIA version 00-10). Specifically, 0.1 to 0.5 ml of 10 wt% surfactant (alkylbenzene sulfonate Neogen SC-A; Daiichi Kogyo Seiyaku) is added to a glass 100 ml beaker, and each toner 0.1 to 0 is added. 0.5 g was added and stirred with a micropartel, and then 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 3 minutes with an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.). The shape and distribution of the toner were measured using the FPIA-2100 until the density of the dispersion was 5000 to 15000 / μl. In this measurement method, it is important that the concentration of the dispersion liquid is 5000 to 15000 / μl from the viewpoint of measurement reproducibility of the average circularity. In order to obtain the dispersion concentration, it is necessary to change the conditions of the dispersion, that is, the amount of surfactant to be added and the amount of toner. The amount of the surfactant varies depending on the hydrophobicity of the toner as in the measurement of the toner particle diameter described above. If it is added in a large amount, noise due to bubbles is generated. It will be enough. Further, the toner addition amount differs from the particle size, and it is necessary to decrease the small particle size and increase the large particle size. When the toner particle size is 3 to 7 μm, the toner amount is 0.1 to 0. By adding 0.5 g, the dispersion concentration can be adjusted to 5000 to 15000 / μl.

(Circularity SF-1, SF-2)
The shape factors SF-1 and SF-2, which are the circularity used in the present invention, are 300 random FE-SEM images of toner obtained by measurement with an FE-SEM (S-4200) manufactured by Hitachi, Ltd. Sampling was performed, and the image information was introduced into an image analysis apparatus (Luzex AP) manufactured by Nireco through an interface for analysis. Values obtained by the following equations were defined as SF-1 and SF-2. The values of SF-1 and SF-2 are preferably values obtained by Luzex, but are not particularly limited to the FE-SEM device and the image analysis device as long as similar analysis results can be obtained.
SF-1 = (L ² / A) × (π / 4) × 100
SF-2 = (P ² / A) × (1 / 4π) × 100
here,
The absolute maximum length of toner is L
The projected area of the toner is A
The maximum toner circumference is P
And In the case of a true sphere, all become 100, and from a spherical shape to an indefinite shape as the value becomes larger than 100. In particular, SF-1 represents the shape of the entire toner (ellipse, sphere, etc.), and SF-2 is a shape factor indicating the degree of surface irregularities.

(Weight average particle diameter, D ₄ / Dn (ratio of weight average particle diameter / number average particle diameter))
The weight average particle diameter (D ₄ ), number average particle diameter (Dn), and ratio (D ₄ / Dn) of the toner can be measured by the following method. The average particle size and particle size distribution of the toner can be measured using a Coulter Counter TA-II, Coulter Multisizer II (both manufactured by Coulter, Inc.) and the like. In particular, Coulter Multisizer II is used in the present invention. The measurement method is described below.
First, 0.1 to 5 ml of a surfactant (preferably polyoxyethylene alkyl ether (nonionic surfactant)) is added as a dispersant to 100 to 150 ml of an electrolytic aqueous solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using primary sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 100 μm aperture as an aperture. Volume distribution and number distribution are calculated. From the obtained distribution, the weight average particle diameter (D ₄ ) and number average particle diameter of the toner can be obtained.

  As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 Less than 35 to 8.00 μm; less than 8.00 to less than 10.08 μm; less than 10.08 to less than 12.70 μm; less than 12.70 to less than 16.00 μm; less than 16.00 to less than 20.20 μm; Uses 13 channels of less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm, and targets particles having a particle size of 2.00 μm to less than 40.30 μm.

(System speed)
In the present invention, the system linear velocity was measured as follows. When A4 paper, longitudinal paper passage (length of paper passage paper: 297 mm), continuous 100 sheets, output by the corresponding image forming apparatus, the output time from the start to the end is A second, and the system speed is B, The system speed was calculated by the following formula.
B (mm / sec) = 100 sheets × 297 mm ÷ A seconds

(Fixing pressure surface pressure)
The fixing pressure surface pressure in the present invention was evaluated using a pressure sensor (PINCH) manufactured by Iwata Industry Co., Ltd.

(Process cartridge)
FIG. 2 is a schematic view showing a configuration of an image forming apparatus including the process cartridge of the present invention. In FIG. 2, the process cartridge has a photosensitive member (latent image carrier), a charging unit, a developing unit, and a cleaning unit.
In the present invention, at least the photosensitive member and the developing unit are integrally combined as a process cartridge among the above-described components such as the photosensitive member, the charging device, the developing unit, and the cleaning unit. And an image forming apparatus main body such as a printer.

(Molecular weight distribution; Mn, Mw)
The number average molecular weight Mn and the weight average molecular weight Mw of the present invention can be measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC was performed with a THF solvent using a Tosoh column / TSKgel Super HM-M (15 cm) using a Tosoh GPC / HLC-8120 as a measuring device. Each average molecular weight is calculated from the measurement result using a molecular weight calibration curve prepared with a monodisperse polystyrene standard sample.

(Glass transition point; Tg)
The glass transition point (Tg) was measured using a TG-DSC system TAS-100 manufactured by Rigaku Corporation.
First, about 10 mg of a sample is placed in an aluminum sample container, which is placed on a holder unit and set in an electric furnace. Next, after heating from room temperature to 150 ° C. at a heating rate of 10 ° C./min, the sample is allowed to stand at 150 ° C. for 10 minutes, and then the sample is cooled to room temperature and left for 10 minutes. Further, the DSC measurement is performed by heating again to 150 ° C. at a heating rate of 10 ° C./min under a nitrogen atmosphere. Tg is calculated from the contact point between the tangent line and the base line of the endothermic curve near Tg, using the analysis system in the TAS-100 system.

(Shell layer containing vinyl resin and resin fine particles used for it)
In the present invention, it is preferable to contain a vinyl resin in the toner shell layer as required, and more preferably to contain a styrene / acrylic resin. Shelling may be performed by covering the toner base particles with resin fine particles and then coating with a solvent or the like (or using the volatility of the solvent), or by annealing the surface with heat or the like to change the coating state. It may be formed.
The resin fine particles used have a glass transition point (Tg) of 40 to 100 ° C., a weight average molecular weight of 3,000 to 300,000 is more preferable, and as described above, the glass transition point (Tg) is less than 40 ° C., and If the weight average molecular weight is less than 3,000, the storage stability of the toner deteriorates, and blocking occurs during storage and in the developing machine. When the glass transition point (Tg) exceeds 100 ° C. and / or the weight average molecular weight exceeds 300,000, the resin fine particles inhibit the adhesiveness to the fixing paper, and the minimum fixing temperature increases.

More preferably, the residual ratio of the resin fine particles to the toner particles is 0.5 to 5.0 wt%. When the residual ratio is less than 0.5 wt%, the storage stability of the toner deteriorates, and blocking occurs during storage and in the developing machine. When the residual amount exceeds 5.0 wt%, the resin fine particles Inhibits the seepage of the wax, and the effect of releasing the wax cannot be sufficiently obtained, and the occurrence of offset is observed.
The residual rate of the resin fine particles can be measured by analyzing a substance caused by the resin fine particles, not by the toner particles, using a pyrolysis gas chromatograph mass spectrometer, and calculating from the peak area. The detector is preferably a mass spectrometer, but is not particularly limited.

As the resin fine particles used for the shell layer, it is preferable to use a vinyl resin.
The vinyl resin is a polymer obtained by homopolymerization or copolymerization of a vinyl monomer, such as a styrene- (meth) acrylate resin, a styrene-butadiene copolymer, a (meth) acrylic acid-acrylate polymer, Examples include styrene-acrylonitrile copolymers, styrene-maleic anhydride copolymers, styrene- (meth) acrylic acid copolymers, and the like.

In addition, polymers of styrene and its substitution products such as polystyrene, poly p-chlorostyrene, polyvinyltoluene; styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, Styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer Polymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene -Butadiene copolymer, styrene-a Puren copolymer, styrene - acrylonitrile - indene copolymer, styrene - maleic acid copolymer, styrene - styrene copolymer and maleic acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, and the like.

(Crystalline polyester resin)
The melting point of the crystalline polyester resin used in the present invention is required to be in the range of 50 to 100 ° C., more preferably in the range of 55 to 90 ° C., and further preferably in the range of 60 to 85 ° C. . When the melting point is lower than 50 ° C., it becomes difficult to store the toner such that block king occurs in the stored toner and to store the fixed image after fixing. Further, when the melting point exceeds 100 ° C., sufficient low-temperature fixability cannot be obtained. In addition, melting | fusing point of the said crystalline polyester resin was calculated | required as the peak temperature of the endothermic peak obtained by the said differential scanning calorimetry (DSC).

  In the present invention, “crystalline polyester resin” means a polymer (copolymer) obtained by polymerizing a component constituting a polyester and another component in addition to a polymer having a 100% polyester structure as a constituent component. To do. However, in the latter case, the component other than the polyester constituting the polymer (copolymer) is 50% by mass or less.

The crystalline polyester resin used in the toner of the present invention is synthesized from, for example, a polyvalent carboxylic acid component and a polyhydric alcohol component. In the present embodiment, a commercially available product may be used as the crystalline polyester resin, or a synthesized product may be used.
Examples of the polyvalent carboxylic acid component include oxalic acid, succinic acid, glutaric acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12 -Aliphatic dicarboxylic acids such as dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid; phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, mesaconic acid Aromatic dicarboxylic acids such as dibasic acids such as, and the like, and anhydrides and lower alkyl esters thereof are also included, but not limited thereto.

  Examples of the trivalent or higher carboxylic acid include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and the like, and anhydrides thereof. And lower alkyl esters. These may be used individually by 1 type and may use 2 or more types together.

  Moreover, as an acid component, the dicarboxylic acid component which has a sulfonic acid group other than the said aliphatic dicarboxylic acid and aromatic dicarboxylic acid may be contained. Furthermore, in addition to the aliphatic dicarboxylic acid and aromatic dicarboxylic acid, a dicarboxylic acid component having a double bond may be contained.

  As the polyhydric alcohol component, an aliphatic diol is preferable, and a linear aliphatic diol having 7 to 20 carbon atoms in the main chain portion is more preferable. If the aliphatic diol is branched, the crystallinity of the polyester resin is lowered, and the melting point may be lowered. Further, when the main chain portion has less than 7 carbon atoms, when polycondensation with an aromatic dicarboxylic acid, the melting temperature becomes high and fixing at low temperature may be difficult, while the main chain portion has 20 carbon atoms. Exceeding the above range makes it difficult to obtain practical materials. The number of carbon atoms in the main chain portion is more preferably 14 or less.

  Specific examples of the aliphatic diol suitably used for the synthesis of the crystalline polyester used in the toner of the present invention include ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,5. -Pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12- Examples include, but are not limited to, dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,14-eicosandecanediol, and the like. Among these, considering availability, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are desirable.

Examples of the trivalent or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and the like. These may be used individually by 1 type and may use 2 or more types together.
Among the polyhydric alcohol components, the content of the aliphatic diol is preferably 80 mol% or more, and more preferably 90% or more. When the content of the aliphatic diol is less than 80 mol%, the crystallinity of the polyester resin is lowered and the melting temperature is lowered, so that toner blocking resistance, image storage stability, and low-temperature fixability may be deteriorated. .

  If necessary, a polycarboxylic acid or a polyhydric alcohol may be added at the final stage of the synthesis for the purpose of adjusting the acid value or the hydroxyl value. Examples of polycarboxylic 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.

  Examples of polyhydric alcohols include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, glycerin; cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, etc. And aromatic diols such as bisphenol A ethylene oxide adduct and bisphenol A propylene oxide adduct.

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

Catalysts usable 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; zinc, manganese, antimony, titanium, tin, zirconium, germanium and the like Metal compounds; phosphorous acid compounds; phosphoric acid compounds; and amine compounds.
Specifically, sodium acetate, sodium carbonate, lithium acetate, lithium carbonate, calcium acetate, calcium stearate, magnesium acetate, zinc acetate, zinc stearate, zinc naphthenate, zinc chloride, manganese acetate, manganese naphthenate, titanium tetraethoxy , Titanium tetrapropoxide, titanium tetraisopropoxide, titanium tetrabutoxide, antimony trioxide, triphenylantimony, tributylantimony, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin oxide, zirconium tetra Butoxide, Zirconium naphthenate, Zirconyl carbonate, Zirconyl acetate, Zirconyl stearate, Zirconyl octylate, Germanium oxide, Trif Alkenyl phosphite, tris (2,4-di -t- butyl-phenyl) phosphite, ethyltriphenylphosphonium bromide, triethylamine, compounds such as triphenyl amine.

The acid value of the crystalline polyester resin used in the present invention (mg number of KOH required to neutralize 1 g of resin) is preferably in the range of 3.0 to 30.0 mgKOH / g, and 6.0 to 25 More desirably, it is in the range of 0.0 mgKOH / g, and further desirably in the range of 8.0 to 20.0 mgKOH / g.
When the acid value is lower than 3.0 mgKOH / g, the dispersibility in water is lowered, and thus it may be very difficult to produce particles by a wet process. In addition, since stability as polymerized particles during aggregation is significantly reduced, it may be difficult to produce an efficient toner. On the other hand, when the acid value exceeds 30.0 mgKOH / g, the hygroscopicity as a toner increases and the toner may be easily affected by the environment.

  The crystalline polyester resin preferably has a weight average molecular weight (Mw) of 6,000 to 35,000. When the molecular weight (Mw) is less than 6,000, the toner may permeate the surface of a recording medium such as paper at the time of fixing to cause fixing unevenness, or the strength of the fixed image against bending resistance may be reduced. On the other hand, when the weight average molecular weight (Mw) exceeds 35,000, the viscosity at the time of melting becomes too high, and the temperature for reaching a viscosity suitable for fixing may be increased, resulting in the deterioration of the low-temperature fixability. There is a case.

  The weight average molecular weight can be measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC was performed with a THF solvent using a Tosoh column / TSKgel Super HM-M (15 cm) using a Tosoh GPC / HLC-8120 as a measuring device. The weight average molecular weight is calculated from the measurement result using a molecular weight calibration curve prepared with a monodisperse polystyrene standard sample.

  The content of the crystalline polyester resin in the toner is preferably in the range of 3 to 40% by mass, more preferably in the range of 4 to 35% by mass, and still more preferably in the range of 5 to 30% by mass. When the content of the crystalline polyester resin is less than 3% by mass, sufficient low-temperature fixability may not be obtained. When the content is more than 40% by mass, sufficient toner strength and fixed image strength cannot be obtained. There is a case where an adverse effect on the charging property is also caused.

  The crystalline resin containing the above crystalline polyester resin is mainly composed of a crystalline polyester resin synthesized from an aliphatic polymerizable monomer (hereinafter sometimes referred to as “crystalline aliphatic polyester resin”). 50 mass% or more) is desirable. Furthermore, in this case, the constituent ratio of the aliphatic polymerizable monomer constituting the crystalline aliphatic polyester resin is preferably 60 mol% or more, and more preferably 90 mol% or more. As the aliphatic polymerizable monomer, the above-mentioned aliphatic diols and dicarboxylic acids can be suitably used.

(Non-crystalline polyester resin)
The toner of the present invention contains an amorphous polyester resin as a binder resin. The non-crystalline polyester resin includes a modified polyester resin and an unmodified polyester resin, and it is more preferable to contain both.
The content ratio of the amorphous polyester resin to 100 parts by weight of the toner is 3 to 20 parts by weight, more preferably 5 to 12 parts by weight.

(Modified polyester resin)
The modified polyester resin is a polyester resin in which a functional group contained in the acid or alcohol monomer unit and a bonding group other than an ester bond exist, or a resin component having a different structure is covalently bonded or ionic bond in the polyester resin. It is the state of being connected by, for example.
For example, the polyester terminal is reacted with something other than an ester bond, specifically, a functional group such as an isocyanate group that reacts with an acid group or a hydroxyl group is introduced at the terminal, and further reacted with an active hydrogen compound, and the terminal is terminated. Those that have been modified or extended are also included.
Furthermore, if it is a compound in which a plurality of active hydrogen groups are present, those in which the polyester ends are bonded together (urea-modified polyester, urethane-modified polyester, etc.) are also included. In addition, a reactive group such as a double bond is introduced into the polyester main chain, and radical polymerization is caused therefrom to introduce a carbon-carbon bond graft component into the side chain, or a double bond is bridged. (Styrene-modified, acrylic-modified polyester, etc.).
In addition, a resin component having a different structure is copolymerized in the main chain of the polyester, or reacted with a carboxyl group or a hydroxyl group at the terminal, for example, a silicone having a terminal modified with a carboxyl group, a hydroxyl group, an epoxy group, or a mercapto group Also included are those copolymerized with resins (silicone-modified polyesters, etc.).
In the present invention, it is preferable to use a modified polyester resin that has been crosslinked and / or elongated using a polyester prepolymer having an isocyanate group as the modified polyester resin. Examples of the polyester prepolymer (A) having an isocyanate group include a product obtained by further reacting a polyester having an active hydrogen group with a polyisocyanate (3), which is a polycondensate of polyol (1) and polycarboxylic acid (2). Can be mentioned. Examples of the active hydrogen group possessed by the polyester include hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like. Among these, alcoholic hydroxyl groups are preferred.

  Examples of the polyol (1) include a diol (1-1) and a tri- or higher valent polyol (1-2). (1-1) alone or (1-1) and a small amount of (1-2) Mixtures are preferred. Diol (1-1) includes alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide phenol compound (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. The trihydric or higher polyol (1-2) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

  Examples of the polycarboxylic acid (2) include dicarboxylic acid (2-1) and trivalent or higher polycarboxylic acid (2-2). (2-1) alone and (2-1) with a small amount of ( The mixture of 2-2) is preferred. Dicarboxylic acid (2-1) includes alkylene dicarboxylic acid (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acid (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acid (phthalic acid, isophthalic acid, terephthalic acid) And naphthalenedicarboxylic acid). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher polycarboxylic acid (2-2) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (trimellitic acid, pyromellitic acid, and the like). In addition, as polycarboxylic acid (2), you may make it react with polyol (1) using the acid anhydride or lower alkyl ester (methyl ester, ethyl ester, isopropyl ester, etc.) of the above-mentioned thing.

  The ratio of the polyol (1) and the polycarboxylic acid (2) is usually 2/1 to 1/1, preferably 1. as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. 5/1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  Examples of the polyisocyanate (3) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); Diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates; polyisocyanates such as phenol derivatives, oximes, caprolactam And a combination of two or more of these.

  The ratio of the polyisocyanate (3) is usually 5/1 to 1/1, preferably 4 /, as the equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. If the molar ratio of [NCO] is less than 1, the urea content in the modified polyester will be low, and the hot offset resistance will deteriorate. The content of the polyisocyanate (3) component in the prepolymer (A) having an isocyanate group at the terminal is usually 0.5 to 40% by weight, preferably 1 to 30% by weight, more preferably 2 to 20% by weight. It is. If it is less than 0.5% by weight, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40% by weight, the low-temperature fixability deteriorates.

  The number of isocyanate groups contained per molecule in the prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2.5 on average. It is. If it is less than 1 per molecule, the molecular weight of the modified polyester after crosslinking and / or elongation becomes low, and the hot offset resistance deteriorates.

(Crosslinking agent and extender)
In the present invention, amines can be used as a crosslinking agent and / or an extender. As amines (B), diamine (B1), trivalent or higher polyamine (B2), aminoalcohol (B3), aminomercaptan (B4), amino acid (B5), and amino acids B1-B5 blocked (B6) etc. are mentioned. Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, Isophorone diamine etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine etc.) and the like. Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. Examples of the B1 to B5 amino group blocked (B6) include ketimine compounds and oxazoline compounds obtained from the B1 to B5 amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.

  Furthermore, if necessary, the molecular weight of the modified polyester after completion of the reaction can be adjusted by using a terminator for crosslinking and / or elongation. Examples of the terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those blocked (ketimine compounds).

  The ratio of amines (B) is the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). The ratio is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2. If [NCO] / [NHx] is greater than 2 or less than 1/2, the molecular weight of the urea-modified polyester (i) becomes low and the hot offset resistance deteriorates.

(Unmodified polyester)
In the present invention, it is preferable that not only the modified polyester alone is used as the non-crystalline polyester resin, but also the unmodified polyester (C) is contained as a toner binder component together with the modified polyester. By using (C) in combination, the low-temperature fixability and the glossiness and gloss uniformity when used in a full-color apparatus are improved. Examples of (C) include the same polycondensates of polyol (1) and polycarboxylic acid (2) as in the polyester component (A), and preferred ones are the same as those described for the modified polyester. . (C) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, and may be modified with, for example, a urethane bond. The modified polyester and (C) are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Accordingly, the polyester component of the modified polyester and (C) preferably have a similar composition. When the modified polyester is contained, the weight ratio of the modified polyester to (C) is usually 5/95 to 75/25, preferably 10/90 to 25/75, more preferably 12/88 to 25/75, particularly preferably. Is 12 / 88-22 / 78. If the weight ratio of the modified polyester is less than 5%, the hot offset resistance is deteriorated, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

  The peak molecular weight of (C) is usually 1000-30000, preferably 1500-10000, more preferably 2000-8000. If it is less than 1000, heat-resistant storage stability will deteriorate, and if it exceeds 10,000, low-temperature fixability will deteriorate. The hydroxyl value of (C) is preferably 5 mgKOH / g or more, more preferably 10 to 120 mgKOH / g, and particularly preferably 20 to 80 mgKOH / g. If it is less than 5 mgKOH / g, it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. The acid value of (C) is usually 0.5 to 40 mgKOH / g, preferably 5 to 35 mgKOH / g. By having an acid value, it tends to be negatively charged. Further, those having an acid value and a hydroxyl value exceeding these ranges are easily affected by the environment under high temperature and high humidity and low temperature and low humidity, and are liable to cause image deterioration.

In the present invention, the glass transition point (Tg) of the toner is usually 40 to 70 ° C., preferably 45 to 55 ° C. If it is less than 40 ° C., the heat-resistant storage stability of the toner deteriorates, and if it exceeds 70 ° C., the low-temperature fixability becomes insufficient. Due to the coexistence of the crosslinked and / or elongated polyester resin, the toner for developing an electrostatic charge image of the present invention exhibits good storage stability even when the glass transition point is low, as compared with known polyester-based toners. As the storage elastic modulus of the toner, the temperature (TG ′) at which the measurement frequency is 20 Hz is 10000 dyne / cm ² is usually 100 ° C. or higher, preferably 110 to 200 ° C. If it is less than 100 ° C., the resistance to hot offset deteriorates. As the viscosity of the toner, the temperature (Tη) at 1000 poise at a measurement frequency of 20 Hz is usually 180 ° C. or less, preferably 90 to 160 ° C. If it exceeds 180 ° C., the low-temperature fixability deteriorates. That is, TG ′ is preferably higher than Tη from the viewpoint of achieving both low temperature fixability and hot offset resistance. In other words, the difference between TG ′ and Tη (TG′−Tη) is preferably 0 ° C. or higher. More preferably, it is 10 degreeC or more, Most preferably, it is 20 degreeC or more. The upper limit of the difference is not particularly limited. Further, from the viewpoint of achieving both heat-resistant storage stability and low-temperature fixability, the difference between Tη and Tg is preferably 0 to 100 ° C. More preferably, it is 10-90 degreeC, Most preferably, it is 20-80 degreeC.

(Coloring agent)
As the coloring agent of the present invention, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide , Ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow ( 5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red , Fais red, parachlorol Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake , Thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyrazolone , Polyazo red, chrome vermillion, benzidine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkali blue rake, peacock blue rake, Victoria blue rake, metal-free phthalocyanine blue, phthalocyanine blue, fast sky blue, in Dunslen Blue (RS, BC), Indigo, Ultramarine Blue, Bitumen, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake Phthalocyanine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

  The colorant used in the present invention can also be used as a master batch combined with a resin. As the binder resin to be kneaded together with the production of the masterbatch or the masterbatch, in addition to the modified and unmodified polyester resins mentioned above, styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene, and polymers of substituted products thereof; Styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer Styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α- Chloromethyl methacrylate copolymer, Tylene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid Styrene copolymers such as acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, poly Acrylic resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. The

  This master batch can be obtained by mixing and kneading a resin for a master batch and a colorant under a high shear force to obtain a master batch. At this time, an organic solvent can be used to enhance the interaction between the colorant and the resin. In addition, a so-called flushing method, which is a wet cake of a coloring agent, is a method of mixing and kneading an aqueous paste containing water of a coloring agent together with a resin and an organic solvent, transferring the coloring agent to the resin side, and removing moisture and organic solvent components. Can be used as it is, so that it is not necessary to dry and is preferably used. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used.

(Release agent)
Further, a wax may be contained as a release agent together with the toner binder and the colorant. Known waxes can be used as the wax of the present invention, such as polyolefin wax (polyethylene wax, polypropylene wax, etc.); long chain hydrocarbon (paraffin wax, sazol wax, etc.); carbonyl group-containing wax, etc. It is done. Of these, carbonyl group-containing waxes are preferred. Carbonyl group-containing waxes include polyalkanoic acid esters (carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18. -Octadecandiol diol distearate, etc.); polyalkanol esters (tristearyl trimellitic acid, distearyl maleate, etc.); polyalkanoic acid amides (ethylenediamine dibehenyl amide, etc.); And dialkyl ketones (such as distearyl ketone). Among these carbonyl group-containing waxes, polyalkanoic acid esters are preferred. The melting point of the wax of the present invention is usually 40 to 160 ° C, preferably 50 to 120 ° C, more preferably 60 to 90 ° C. A wax having a melting point of less than 40 ° C. has an adverse effect on heat resistant storage stability, and a wax having a melting point of more than 160 ° C. tends to cause a cold offset when fixing at a low temperature. Further, the melt viscosity of the wax is preferably 5 to 1000 cps, more preferably 10 to 100 cps as a measured value at a temperature 20 ° C. higher than the melting point. Waxes exceeding 1000 cps have poor effects for improving hot offset resistance and low-temperature fixability. The content of the wax in the toner is usually 0 to 40% by weight, preferably 3 to 30% by weight.

(Charge control agent)
The toner of the present invention may contain a charge control agent as necessary. All known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified). Quaternary ammonium salts), alkylamides, phosphorus simple substances or compounds, tungsten simple substances or compounds, fluorine-based activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Nitronine dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, oxynaphthoic acid metal complex E-82, salicylic acid metal complex E- 84, E-89 of a phenol-based condensate (above, Orient Chemical Industry Co., Ltd.), TP-302 of a quaternary ammonium salt molybdenum complex, TP 1415 (above, Hodogaya Chemical Industry Co., Ltd.), quaternary ammonium Copy charge PSY VP2038 of salt, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (above, manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit Co., Ltd.), copper phthalocyanine, perylene, quinacridone Azo pigments, sulfonate group, carboxyl group, and polymer compounds having a functional group such as a quaternary ammonium salt.

  In the present invention, the amount of charge control agent used is determined by the toner production method including the type of binder resin, the presence or absence of additives used as necessary, and the dispersion method, and is uniquely limited. However, it is preferably used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the main charge control agent is reduced, the electrostatic attractive force with the developing roller is increased, the flowability of the developer is reduced, and the image density is reduced. Incurs a decline. These charge control agents can be dissolved and dispersed after being melt-kneaded with a masterbatch and resin, and of course, they can be added directly when dissolved and dispersed in an organic solvent, or fixed on the toner surface after preparation of toner particles. May be.

(External additive)
As an external additive for assisting fluidity, developability and chargeability of the colored particles obtained in the present invention, inorganic fine particles and hydrophobic treated inorganic fine particles can be used in combination with oxide fine particles. The average particle size of the primary particles of the hydrophobized inorganic fine particles is from 1 to 150 nm, more preferably from 5 nm to 70 nm, and it is more desirable to contain at least one kind of these inorganic fine particles. If it is smaller than this range, the inorganic fine particles are buried in the toner, and the function is hardly exhibited effectively. On the other hand, if it is larger than this range, the surface of the photoreceptor is undesirably damaged.
Further, it is more preferable that the hydrophobized primary particles contain at least one kind of inorganic fine particles having an average particle diameter of 20 nm or less and at least one kind of inorganic fine particles of 30 nm or more. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g.
Any of them can be used as long as the conditions are satisfied. For example, silica fine particles, hydrophobic silica, fatty acid metal salts (such as zinc stearate and aluminum stearate), metal oxides (such as titania, alumina, tin oxide, and antimony oxide), fluoropolymers, and the like may be contained.
The external additive may be added in an amount of 0.1 to 5% by weight, preferably 0.3 to 3% by weight, based on the toner.

  Particularly suitable additives include hydrophobized silica, titania, titanium oxide, and alumina fine particles. Silica fine particles include HDK H 2000, HDK H 2000/4, HDK H 2050EP, HVK21, HDK H 1303 (above Hoechst) and R972, R974, RX200, RY200, R202, R805, and R812 (above Nippon Aerosil). Further, as titania fine particles, P-25 (Nippon Aerosil), STT-30, STT-65C-S (above Titanium Industry), TAF-140 (Fuji Titanium Industry), MT-150W, MT-500B, MT-600B MT-150A (taker above). Particularly, the hydrophobized titanium oxide fine particles include T-805 (Nippon Aerosil), STT-30A, STT-65S-S (above Titanium Industry), TAF-500T, TAF-1500T (above Fuji Titanium Industry), MT -100S, MT-100T (above Taka), IT-S (Ishihara Sangyo), etc.

  In order to obtain hydrophobized oxide fine particles, silica fine particles, titania fine particles, and alumina fine particles, hydrophilic fine particles are treated with a silane coupling agent such as methyltrimethoxysilane, methyltriethoxysilane, or octyltrimethoxysilane. Can be obtained. In addition, silicone oil-treated oxide fine particles and inorganic fine particles obtained by treating silicone oil with heat if necessary to treat it with inorganic fine particles are also suitable.

  Examples of the silicone oil include dimethyl silicone oil, methylphenyl silicone oil, chlorophenyl silicone oil, methyl hydrogen silicone oil, alkyl modified silicone oil, fluorine modified silicone oil, polyether modified silicone oil, alcohol modified silicone oil, amino modified silicone. Oil, epoxy-modified silicone oil, epoxy-polyether-modified silicone oil, phenol-modified silicone oil, carboxyl-modified silicone oil, mercapto-modified silicone oil, acrylic, methacryl-modified silicone oil, α-methylstyrene-modified silicone oil, and the like can be used. Examples of the inorganic fine particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, iron oxide, copper oxide, zinc oxide, tin oxide, quartz sand, clay, mica, and silica ash. Examples thereof include stone, diatomaceous earth, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, parium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. Of these, silica and titanium dioxide are particularly preferred.

  Other polymer fine particles such as polystyrene, methacrylic acid ester and acrylic acid ester copolymer obtained by soap-free emulsion polymerization, suspension polymerization, and dispersion polymerization, polycondensation systems such as silicone, benzoguanamine, and nylon, and thermosetting resins Examples include polymer particles.

  Such a fluidizing agent can be surface-treated to increase hydrophobicity and prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents, silane coupling agents having an alkyl fluoride group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils and the like are preferable surface treatment agents. .

  Examples of the cleaning property improver for removing the developer after transfer remaining on the photoreceptor or the primary transfer medium include, for example, zinc stearate, calcium stearate, fatty acid metal salts such as stearic acid, such as polymethyl methacrylate fine particles, polystyrene fine particles, etc. And polymer fine particles produced by soap-free emulsion polymerization. The polymer fine particles preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

The dry toner of the present invention can be produced by the following method, but is not limited thereto.
(Toner production method in aqueous medium)
The aqueous phase used in the present invention is more preferably used by adding resin fine particles in advance. The water used in the aqueous phase may be water alone, or a solvent miscible with water may be used in combination. Examples of the miscible solvent include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methylcellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.) and the like.

Toner particles are obtained by reacting a dispersion containing an isocyanate group-containing polyester prepolymer (A) dissolved or dispersed in an organic solvent in an aqueous phase with amines (B). As a method for stably forming a dispersion containing the polyester prepolymer (A) in the aqueous phase, a composition of a toner raw material comprising the polyester prepolymer (A) dissolved or dispersed in an organic solvent in the aqueous phase is used. In addition, a method of dispersing by shearing force may be mentioned. A polyester prepolymer (A) dissolved or dispersed in an organic solvent and other toner composition (hereinafter referred to as toner raw material), a colorant masterbatch, a release agent, a charge control agent, a crystalline polyester resin Unmodified polyester resin and the like may be mixed when forming the dispersion in the aqueous phase, but after the toner raw materials are mixed in advance and dissolved or dispersed in an organic solvent, the mixture is added to the aqueous phase. It is more preferable to disperse them.
In the present invention, other toner raw materials such as a charge control agent are not necessarily mixed when forming particles in an aqueous phase, and may be added after the particles are formed.

  Prepolymer (A) having an isocyanate group is required to heat polyol (1) and polycarboxylic acid (2) to 150 to 280 ° C. in the presence of a known esterification catalyst such as tetrabutoxy titanate or dibutyltin oxide. The water produced while distilling under reduced pressure is distilled off to obtain a polyester having a hydroxyl group, which is then reacted at 40 to 140 ° C. with polyisocyanate (3).

  The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. In order to make the particle size of the dispersion 2 to 20 μm, a high-speed shearing type is preferable. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C. Higher temperatures are preferred in that the dispersion of the polyester prepolymer (A) has a low viscosity and is easy to disperse.

  The amount of the aqueous phase used is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight, based on 100 parts of the toner composition containing the polyester prepolymer (A). If the amount is less than 50 parts by weight, the dispersion state of the toner composition is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 20000 parts by weight, it is not economical. Moreover, a dispersing agent can also be used as needed. It is preferable to use a dispersant because the particle size distribution becomes sharp and the dispersion is stable.

  Anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino acids as dispersants for emulsifying and dispersing the oily phase in which the toner composition is dispersed in the aqueous phase Amine salt types such as alcohol fatty acid derivatives, polyamine fatty acid derivatives, imidazoline, and quaternary ammonium such as alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride Nonionic surfactants such as salt-type cationic surfactants, fatty acid amide derivatives, polyhydric alcohol derivatives such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-di Amphoteric surfactants such as chill ammonium betaine.

  Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [omega-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [omega-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts thereof, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- (2-hydroxyethyl ) Perfluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate Etc.,

  Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (Daikin Kogyo Co., Ltd.), Mega-Fac F-l0, F-l20, F-113, F-191, F-812, F-833 (Dainippon Ink Co., Ltd.), Xtop EF-102 , 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fagento F-100, F150 (manufactured by Neos).

  Cationic surfactants include aliphatic primary, secondary or tertiary amine acids having a fluoroalkyl group, aliphatic quaternary ammonium salts such as perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salts, benzaza Luconium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-21 (Asahi Glass), Florard FC-135 (Sumitomo 3M), Unidyne DS-202 (Daikin Industries) , Megafac F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products Co., Ltd.), Footgent F-300 (Neos Co., Ltd.), and the like.

Further, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite and the like can be used as an inorganic compound dispersant which is hardly soluble in water.
Further, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomers containing hydroxyl groups Such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloroacrylate 2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N -Methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, etc., or esters of compounds containing vinyl alcohol and carboxyl groups, such as Vinyl acetate, vinyl propionate, vinyl butyrate, etc., acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, vinyl pyridine, vinyl pyrrolidone, vinyl imidazole, ethyleneimine, etc. Homopolymers or copolymers such as those having a nitrogen atom or a heterocyclic ring thereof, polyoxyethylene, polyoxypropylene, Oxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonylphenyl Polyoxyethylenes such as esters, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

In addition, when an acid such as calcium phosphate salt or an alkali-soluble substance is used as the dispersion stabilizer, the calcium phosphate salt is removed from the fine particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. To do. It can also be removed by operations such as enzymatic degradation.
When a dispersant is used, the dispersant may remain on the surface of the toner particles, but it is preferable from the charged surface of the toner that the dispersant is washed and removed after the elongation and / or crosslinking reaction.

  The elongation and / or cross-linking reaction time is selected depending on the reactivity of the isocyanate group structure of the prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. is there. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

In order to remove the organic solvent from the obtained emulsified dispersion, a method in which the temperature of the entire system is gradually raised to completely evaporate and remove the organic solvent in the droplets can be employed. Alternatively, the emulsified dispersion can be sprayed into a dry atmosphere to completely remove the water-insoluble organic solvent in the droplets to form toner fine particles, and the aqueous dispersant can be removed by evaporation together. . As a dry atmosphere in which the emulsified dispersion is sprayed, a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, or the like, in particular, various air streams heated to a temperature equal to or higher than the boiling point of the highest boiling solvent used are generally used. Sufficient quality can be obtained with a short treatment such as spray dryer, belt dryer or rotary kiln.
Further, as a method for removing the organic solvent, air can be blown away by a rotary evaporator or the like.

Thereafter, rough separation is performed by centrifugal separation, the emulsified dispersion is washed in a washing tank, and the drying process is repeated in a hot air dryer, and the solvent is removed and dried to obtain a toner base.
It is preferable to put an aging step after drying, and the aging conditions are 30 to 55 ° C. (more preferably 40 to 50 ° C.) and 5 to 36 hours (more preferably 10 to 24 hours).

When the particle size distribution at the time of emulsification dispersion is wide and washing and drying processes are performed while maintaining the particle size distribution, the particle size distribution can be adjusted by classifying into a desired particle size distribution.
In the classification operation, the fine particle portion can be removed in the liquid by a cyclone, a decanter, centrifugation, or the like. Of course, the classification operation may be performed after obtaining the powder as a powder after drying. The unnecessary fine particles or coarse particles obtained can be returned to the kneading step and used for the formation of particles. At that time, fine particles or coarse particles may be wet.
The dispersant used is preferably removed from the obtained dispersion as much as possible, but it is preferable to carry out it simultaneously with the classification operation described above.

The obtained dried toner powder is mixed and mixed with different particles such as charge control fine particles and fluidizer fine particles, and mechanical impact force is applied to the mixed powder to fix and fuse on the surface. Thus, detachment of the foreign particles from the surface of the obtained composite particle can be prevented.
Specific means include a method of applying an impact force to the mixture by blades rotating at high speed, a method of injecting and accelerating the mixture in a high-speed air stream, and causing particles or composite particles to collide with an appropriate collision plate, etc. is there. As equipment, Ong mill (manufactured by Hosokawa Micron Co., Ltd.), I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) is modified to reduce the pulverization air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar, etc.
Finally, an external additive such as inorganic fine particles and a toner are mixed with a Henschel mixer or the like, and coarse particles are removed with an ultrasonic sieve or the like to obtain a final toner.

(Carrier for two-component developer)
When the toner of the present invention is used for a two-component developer, it may be used by mixing with a magnetic carrier. The carrier to toner content ratio in the developer is 1 to 10 weights of toner with respect to 100 parts by weight of carrier. Part is preferred. As the magnetic carrier, conventionally known ones such as iron powder, ferrite powder, magnetite powder, magnetic resin carrier having a particle diameter of about 20 to 200 μm can be used. Examples of the coating material include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, Halogenated olefin resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride And fluoro such as terpolymers of non-fluoride monomers including, and silicone resins. Moreover, you may contain electrically conductive powder etc. in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide or the like can be used. These conductive powders preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance.
The toner of the present invention can also be used as a one-component magnetic toner that does not use a carrier or a non-magnetic toner.

(Supply toner)
In the present invention, as the replenishment toner, a toner containing a carrier containing about 0 to 20% by weight of the carrier in the toner can be used as the replenishment toner.
In an image forming apparatus using a two-component developer, the carrier deteriorates as the number of output images increases, and the carrier coat layer is gradually scraped or the low-temperature melting component of the toner, external additives, etc. The phenomenon of carrier spent adhering to the toner occurs, and the charging ability inherent to the carrier cannot be exhibited, which is not preferable because it causes image deterioration such as image background contamination. Therefore, it is possible to extend the total carrier life by gradually discharging the deteriorated carriers and supplying new carriers instead.

(Tandem type color image forming device)
The present invention can also be used as a color image forming apparatus of a tandem development system in which at least four development units having different development colors are arranged in series. An example of an embodiment of a tandem type color image forming apparatus will be described. As shown in FIG. 3, the tandem type electrophotographic apparatus includes a direct transfer system in which an image on each photoconductor 1 is sequentially transferred onto a sheet s conveyed by a sheet conveying belt 3 by a transfer apparatus 2; As shown in FIG. 4, the images on the respective photoconductors 1 are once sequentially transferred to the intermediate transfer member 4 by the primary transfer device 2, and then the images on the intermediate transfer member 4 are transferred to the sheet s by the secondary transfer device 5. There are indirect transfer systems that perform batch transfer. The transfer device 5 is a transfer conveyance belt, but there are also roller shapes and methods.

Comparing the direct transfer type with the indirect transfer type, the former arranges the sheet feeding device 6 on the upstream side of the tandem type image forming apparatus T on which the photoconductors 1 are arranged, and the fixing device 7 on the downstream side. There is a drawback in that the size increases in the sheet conveying direction.
On the other hand, the latter can set the secondary transfer position relatively freely.
The sheet feeding device 6 and the fixing device 7 can be arranged so as to overlap with the tandem image forming apparatus T, and there is an advantage that downsizing is possible.

In the former, in order not to increase the size in the sheet conveying direction, the fixing device 7 is arranged close to the tandem type image forming apparatus T. Therefore, the fixing device 7 cannot be disposed with a sufficient margin that the sheet s can bend, and an impact (particularly with a thick sheet) when the leading edge of the sheet s enters the fixing device 7 or fixing. Due to the difference in speed between the sheet conveyance speed when passing through the apparatus 7 and the sheet conveyance speed by the transfer conveyance belt, there is a drawback that the fixing device 7 tends to affect image formation on the upstream side.
On the other hand, in the latter case, the fixing device 7 can be disposed with a sufficient margin that the sheet s can be bent, so that the fixing device 7 can hardly affect the image formation.

In view of the above, recently, an indirect transfer type of tandem type electrophotographic apparatus has attracted attention.
In this type of color electrophotographic apparatus, as shown in FIG. 4, the transfer residual toner remaining on the photoreceptor 1 after the primary transfer is removed by the photoreceptor cleaning device 8 to clean the surface of the photoreceptor 1. In preparation for another image formation. Further, the transfer residual toner remaining on the intermediate transfer body 4 after the secondary transfer is removed by the intermediate transfer body cleaning device 9 to clean the surface of the intermediate transfer body 4 to prepare for image formation again.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 5 shows an embodiment of the present invention, which is a tandem indirect transfer type electrophotographic apparatus. In the figure, reference numeral 100 is a copying apparatus main body, 200 is a paper feed table on which the copying apparatus is placed, 300 is a scanner mounted on the copying apparatus main body 100, and 400 is an automatic document feeder (ADF) mounted thereon. The copying machine main body 100 is provided with an endless belt-shaped intermediate transfer member 10 at the center.
Then, as shown in FIG. 5, in the illustrated example, it is wound around three support rollers 14, 15, and 16 so that it can be rotated and conveyed clockwise in the figure.
In this illustrated example, an intermediate transfer body cleaning device 17 for removing residual toner remaining on the intermediate transfer body 10 after image transfer is provided on the left of the second support roller 15 among the three.
Among the three images, four images of yellow, cyan, magenta, and black are arranged on the intermediate transfer member 10 stretched between the first support roller 14 and the second support roller 15 along the conveyance direction. The tandem image forming apparatus 20 is configured by arranging the forming units 18 side by side.

An exposure device 21 is further provided on the tandem image forming apparatus 20 as shown in FIG. On the other hand, a secondary transfer device 22 is provided on the side opposite to the tandem image forming apparatus 20 with the intermediate transfer body 10 interposed therebetween. In the illustrated example, the secondary transfer device 22 is configured by spanning a secondary transfer belt 24, which is an endless belt, between two rollers 23, and is pressed against the third support roller 16 via the intermediate transfer body 10. The image on the intermediate transfer body 10 is transferred to a sheet.
A fixing device 25 for fixing the transfer image on the sheet is provided beside the secondary transfer device 22. The fixing device 25 is configured by pressing a pressure roller 27 against a fixing belt 26 that is an endless belt.
The secondary transfer device 22 described above is also provided with a sheet transport function for transporting the image-transferred sheet to the fixing device 25. Of course, a transfer roller or a non-contact charger may be arranged as the secondary transfer device 22, and in such a case, it is difficult to provide this sheet conveying function together.
In the illustrated example, under such a secondary transfer device 22 and a fixing device 25, a sheet reversing device 28 for reversing the sheet so as to record images on both sides of the sheet in parallel with the tandem image forming device 20 described above. Is provided.

Now, when making a copy using this color electrophotographic apparatus, a document is set on the document table 30 of the automatic document feeder 400. Alternatively, the automatic document feeder 400 is opened, a document is set on the contact glass 32 of the scanner 300, and the automatic document feeder 400 is closed and pressed by it.
When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the other contact glass 32. At that time, the scanner 300 is immediately driven to travel the first traveling body 33 and the second traveling body 34. Then, the first traveling body 33 emits light from the light source and further reflects the reflected light from the document surface toward the second traveling body 34, and is reflected by the mirror of the second traveling body 34 and passes through the imaging lens 35. The document is placed in the reading sensor 36 and the original content is read.

When a start switch (not shown) is pressed, one of the support rollers 14, 15, and 16 is driven to rotate by a drive motor (not shown), and the other two support rollers are driven to rotate to convey the intermediate transfer member 10. To do. At the same time, the individual image forming means 18 rotates the photoconductor 40 to form black, yellow, magenta, and cyan monochrome images on each photoconductor 40. Then, along with the conveyance of the intermediate transfer member 10, the single color images are sequentially transferred to form a composite color image on the intermediate transfer member 10.
On the other hand, when a start switch (not shown) is pressed, one of the paper feed rollers 42 of the paper feed table 200 is selectively rotated, and the sheet is fed out from one of the paper feed cassettes 44 provided in multiple stages in the paper bank 43, and the separation roller 45. Then, the sheets are separated one by one into the paper feed path 46, transported by the transport roller 47, guided to the paper feed path 48 in the copying machine main body 100, and abutted against the registration roller 49 and stopped.
Alternatively, the sheet feed roller 50 is rotated to feed out the sheets on the manual feed tray 51, separated one by one by the separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped.
Then, the registration roller 49 is rotated in synchronization with the composite color image on the intermediate transfer member 10, the sheet is fed between the intermediate transfer member 10 and the secondary transfer device 22, and transferred by the secondary transfer device 22. A color image is recorded on the sheet.

The sheet after the image transfer is conveyed by the secondary transfer device 22 and sent to the fixing device 25, and heat and pressure are applied to the fixing device 25 to fix the transferred image. The paper is discharged at 56 and stacked on the paper discharge tray 57. Alternatively, it is switched by the switching claw 55 and put into the sheet reversing device 28, where it is reversed and guided again to the transfer position, and an image is recorded also on the back surface, and then discharged onto the discharge tray 57 by the discharge roller 56.
On the other hand, the intermediate transfer body 10 after the image transfer is removed by the intermediate transfer body cleaning device 17 to remove residual toner remaining on the intermediate transfer body 10 after the image transfer, so that the tandem image forming apparatus 20 can prepare for another image formation.
Here, the registration roller 49 is generally used while being grounded, but it is also possible to apply a bias for removing paper dust from the sheet.

  Now, in the tandem image forming apparatus 20 described above, the individual image forming means 18 includes, for example, a charging device 60, a developing device 61, and a primary device around a drum-shaped photoconductor 40 as shown in FIG. The image forming apparatus includes a transfer device 62, a photoconductor cleaning device 63, a charge removal device 64, and the like.

EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited thereto.
Hereinafter, a part shows a weight part.

(Evaluation machine)
The developing unit and fixing unit of imagio MP C6000 were modified and used as an evaluation machine. The modified contents were used in a state where the development gap was 1.26 mm, the doctor blade gap was 1.6 mm, and the reflective photosensor function was turned off so that the linear velocity was 1700 mm / sec. The fixing unit of the fixing unit had a fixing surface pressure of 39 N / cm ² and a fixing nip width of 10 mm. The fixing medium surface was coated with tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin (PFA), molded, and surface-adjusted. The actual temperature regions of the image carrier, the developing device, and the transfer device unit were controlled to be 30 to 40 ° C. The heating temperature of the fixing roller was set to 130 ° C.

(Evaluation of two-component developer)
When evaluating an image with a two-component developer, a ferrite carrier having an average particle diameter of 35 μm coated with a silicone resin at an average thickness of 0.5 μm is used as follows, and toner 7 of each color is used with respect to 100 parts by weight of the carrier. A developer was prepared by uniformly mixing and charging parts by weight using a tumbler mixer of a type in which the container was rolled and stirred.

(Carrier production)
・ Core material Mn ferrite particles (weight average diameter: 35 μm) 5000 parts ・ Coating material Toluene 50 parts Silicone resin SR2400 (made by Toray Dow Corning Silicone, nonvolatile content 50%)
450 parts Aminosilane SH6020 (manufactured by Toray Dow Corning Silicone) 10 parts Carbon black 10 parts The above coating material is dispersed with a stirrer for 10 minutes to prepare a coating liquid, and the coating liquid and the core material are rotated in the fluidized bed. The coating liquid was applied to the core material by applying the coating liquid while forming a swirling flow provided with a disk and stirring blades. The obtained coated material was baked in an electric furnace at 250 ° C. for 2 hours to obtain the carrier.

(Synthesis of resin fine particles)
Charge ion exchange water and monomer into a reaction vessel equipped with a cooling tube, a stirrer, a gas introduction tube and a thermometer. The formulation example is described as [resin fine particle dispersion 1, 2, 3] in Table 1. The liquid was heated with stirring, the temperature was raised to the specified reaction temperature, and the reaction time was all 8 hours, and vinyl resin aqueous dispersions [resin fine particle dispersions 1, 2, 3] were obtained.
The volume average particle diameters of the [resin fine particle dispersions 1, 2, 3] measured by a laser diffraction / scattering particle size distribution analyzer (LA-920) manufactured by HORIBA, Ltd. were 360 nm, 270 nm, and 190 nm, respectively. A part of [resin fine particle dispersions 1, 2, 3] was dried to isolate the resin component to obtain [resin fine particles 1, 2, 3]. The Tg of the resin fine particles was 68 ° C., 66 ° C. and 62 ° C., respectively, and the peak average molecular weights were 13000, 11000 and 8000, respectively.

[Example 1]
~ Preparation of aqueous phase ~
500 parts of water, 83 parts of [resin fine particle dispersion 1], 23 parts of a 48.3% aqueous solution of sodium dodecyldiphenyl ether disulfonate (Eleminol MON-7) manufactured by Sanyo Chemical Industries, Ltd., and 50 parts of ethyl acetate were mixed and stirred to give a milky white color Obtained liquid. This is designated as [Aqueous Phase 1].

~ Synthesis of non-crystalline polyester resin ~
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 229 parts of bisphenol A ethylene oxide 2-mole adduct, 329 parts of bisphenol A propylene oxide 3-mole adduct, 208 parts terephthalic acid, 80 parts adipic acid and dibutyl 2 parts of tin oxide was added, reacted at 230 ° C. for 7 hours at normal pressure, and further reacted for 5 hours at a reduced pressure of 10-15 mmHg. Then, 35 parts of trimellitic anhydride was added to the reaction vessel, and 2 parts at 180 ° C. under normal pressure. By reacting for a time, [amorphous polyester resin 1] was obtained. [Amorphous polyester resin 1] had a number average molecular weight of 2000, a weight average molecular weight of 3800, Tg of 40 ° C., and an acid value of 25 mgKOH / g.

~ Synthesis of non-crystalline intermediate polyester ~
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, trimellitic anhydride 22 And 2 parts of dibutyltin oxide were added, reacted at 230 ° C. at normal pressure for 7 hours, and further reacted at reduced pressure of 10 to 15 mmHg for 5 hours to obtain [Amorphous Intermediate Polyester 1]. [Amorphous Intermediate Polyester 1] had a number average molecular weight of 2200, a weight average molecular weight of 9700, Tg of 54 ° C., an acid value of 0.5 mgKOH / g, and a hydroxyl value of 52 mgKOH / g.
Next, 410 parts of [Amorphous Intermediate Polyester 1], 89 parts of isophorone diisocyanate, and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. [Prepolymer 1] was obtained. [Prepolymer 1] had a free isocyanate weight% of 1.53%.

~ Synthesis of ketimine ~
In a reaction vessel equipped with a stirrer and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 4 and a half hours to obtain [ketimine compound 1]. The amine value of [ketimine compound 1] was 417.

~ Synthesis of crystalline polyester resin In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 1200 parts of 1,6-hexanediol, 1200 parts of decanedioic acid, and 0.4 parts of dibutyltin oxide as a catalyst Then, the air in the container was made an inert atmosphere with nitrogen gas by depressurization, and the mixture was stirred at 180 rpm with mechanical stirring for 5 hours. Thereafter, the temperature was gradually raised to 220 ° C. under reduced pressure, and the mixture was stirred for 2 hours. When it became viscous, it was air-cooled to stop the reaction, thereby obtaining [Crystalline Polyester Resin 1]. [Crystalline polyester resin 1] had a number average molecular weight of 3700, a weight average molecular weight of 16000, and a melting point of 69 ° C.

~ Synthesis of master batch (MB) ~
1200 parts of water, 540 parts of carbon black (made by Printex 35 Dexa) [DBP oil absorption = 42 ml / 100 mg, pH = 9.5] and 1200 parts of polyester resin are added and mixed with a Henschel mixer (made by Mitsui Mining Co., Ltd.). After kneading at 110 ° C. for 1 hour using two rolls, the product was rolled and cooled, and pulverized with a pulverizer to obtain [Masterbatch 1].

~ Creation of oil phase ~
378 parts of [Non-crystalline polyester resin 1], 120 parts of paraffin WAX (melting point 90 ° C.), 200 parts of [crystalline polyester resin 1] and 947 parts of ethyl acetate are charged in a container equipped with a stir bar and a thermometer. The temperature was raised to 80 ° C., kept at 80 ° C. for 5 hours, and then cooled to 30 ° C. over 1 hour. Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution 1].
[Raw material solution 1] 1324 parts are transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), a liquid feeding speed of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 0.5 mm zirconia beads are 80% by volume. Carbon black and WAX were dispersed under conditions of filling and 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [Amorphous Polyester Resin 1] was added, followed by two passes with a bead mill under the above conditions to obtain [Pigment / WAX Dispersion 1]. The solid content concentration of [Pigment / WAX Dispersion 1] (130 ° C., 30 minutes) was 50%.

~ Emulsification⇒Desolvation ~
[Pigment / WAX Dispersion 1] 749 parts, [Prepolymer 1] 115 parts, [Ketimine Compound 1] 2.9 parts in a container and TK homomixer (manufactured by Tokushu Kika) at 5,000 rpm for 2 minutes After mixing, 1200 parts of [Aqueous phase 1] was added to the container, and mixed with a TK homomixer at 13,000 rpm for 25 minutes to obtain [Emulsion slurry 1].
[Emulsion slurry 1] was charged into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, aging was carried out at 40 ° C. for 24 hours to obtain [Dispersion slurry 1].

~ Washing⇒Drying ~
[Dispersion Slurry 1] After filtering 100 parts under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(2): 100 parts of 10% aqueous sodium hydroxide solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
(3): 100 parts of 10% hydrochloric acid was added to the filter cake of (2), mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(4): 300 parts of ion-exchanged water was added to the filter cake of (3), mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered twice to obtain [filter cake 1]. It was.
[Filter cake 1] was dried at 45 ° C. for 48 hours in a circulating dryer. Thereafter, sieved with a mesh of 75 μm, [Toner Base Particle 1] was obtained.
Thereafter, 100 parts of [toner base particle 1] and 1 part of hydrophobized silica having a particle diameter of 13 nm were mixed with a Henschel mixer to obtain a toner. The physical properties of the obtained toner are shown in Table 2, and the evaluation results are shown in Table 3.

[Example 2]
A toner was obtained in the same manner as in Example 1 except that [resin fine particle dispersion 1] used in Example 1 was changed to [resin fine particle dispersion 2]. The physical properties of the obtained toner are shown in Table 2, and the evaluation results are shown in Table 3.
[Example 3]
A toner was obtained in the same manner as in Example 1 except that [resin fine particle dispersion 1] used in Example 1 was changed to [resin fine particle dispersion 3]. The physical properties of the obtained toner are shown in Table 2, and the evaluation results are shown in Table 3.

[Example 4]
A toner was obtained in the same manner as in Example 1 except that [resin fine particle dispersion 1] used in Example 1 was changed to the following [resin fine particle dispersion 4]. The physical properties of the obtained toner are shown in Table 2, and the evaluation results are shown in Table 3.
-Preparation of resin fine particle dispersion 4-
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 350 parts of an ethylene oxide 2-mole adduct of bisphenol A, 326 parts of a propion oxide 3-mole adduct of bisphenol A, 278 parts of terephthalic acid, 40 of phthalic anhydride 2 parts of titanium dihydroxybis (triethanolamate) as a condensation catalyst was added, and the reaction was carried out for 10 hours while distilling off the water produced at 230 ° C. under a nitrogen stream. Next, the reaction is carried out under reduced pressure of 5 to 20 mmHg. When the acid value becomes 2 mgKOH / g or less, it is cooled to 180 ° C., 62 parts of trimellitic anhydride is added, taken out after reaction for 2 hours under normal pressure sealing, and taken to room temperature. After cooling, it was pulverized to obtain [Amorphous Polyester Resin 2].
The obtained [Non-crystalline polyester resin 2] had an acid value of 35 mgKOH / g, a hydroxyl value of 17 mgKOH / g, Tg of 69 ° C., Mn of 3980, and Mw of 24400.

[Non-crystalline polyester resin 2] was coarsely pulverized with a hammer mill to prepare a resin particle dispersion.
50 parts by weight of ethyl acetate and 110 parts by weight of IPA were added to a ₂ L separable flask equipped with an anchor blade for supplying stirring power, a reflux device, and a decompression device using a vacuum pump, and N ₂ was fed at a rate of 0.2 L / m. The air in the system was replaced with N ₂ . Next, 200 parts by weight of the crystalline polyester resin 1 was slowly added while being heated to 60 ° C. by an in-system oil bath device, and dissolved while stirring. Next, 20 parts by weight of 5% ammonia water was added thereto, and then 460 parts by weight of ion-exchanged water was added thereto at a rate of 4.0 g / m with stirring using a metering pump. Emulsification was completed when the emulsification system was milky white and the stirring viscosity was reduced.
Next, the pressure was reduced to -700 Torr, and the mixture was stirred for 40 minutes while stirring. Further, 50 parts by weight of pure water at 60 ° C. was added thereto, and stirring was continued for 20 minutes under reduced pressure. When the reflux amount reached 210 parts by weight, this was taken as the end point, and overheating was stopped and the mixture was cooled to room temperature while stirring. The particle size of the obtained resin particles was measured using a laser diffraction / scattering particle size distribution analyzer (LA-920, manufactured by Horiba, Ltd.). The average particle size of the obtained resin fine particles was 344 nm.

[Example 5]
In Example 2, a toner was obtained in the same manner as in Example 2 except that [Prepolymer 1] and the ketimine compound were not contained. The toner contained no modified polyester, and no toner was stretched or crosslinked. The physical properties of the obtained toner are shown in Table 2, and the evaluation results are shown in Table 3.

[Comparative Example 1]
A toner was obtained in the same manner as in Example 1 except that [resin fine particle dispersion 1] used in Example 1 was changed to the following [resin fine particle dispersion 5]. The physical properties of the obtained toner are shown in Table 2, and the evaluation results are shown in Table 3.
-Preparation of resin fine particle dispersion 5-
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 10 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 170 parts of methacrylic acid, 100 butyl acrylate Parts and 1 part of ammonium persulfate were added and stirred at 3800 rpm for 30 minutes to obtain a white emulsion. The system was heated to raise the system temperature to 75 ° C. and reacted for 3 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 70 ° C. for 5 hours, and an aqueous dispersion of vinyl resin (methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt copolymer). [Resin fine particle dispersion 5] was obtained. The volume average particle diameter of [resin fine particle dispersion 5] measured with LA-920 was 60 nm. A portion of [resin fine particle dispersion 5] was dried to isolate the resin component. The Tg of the resin was 60 ° C., and the weight average molecular weight was 110,000.
The resin fine particles obtained had a small particle size, and the toner base particles did not have a sufficiently distinguishable core-shell structure.

[Comparative Example 2]
A toner was obtained in the same manner as in Example 1 except that it was formulated without containing a crystalline polyester resin. The physical properties of the obtained toner are shown in Table 2, and the evaluation results are shown in Table 3.

[Comparative Example 3]
A toner was obtained in the same manner as in Example 1 except that [resin fine particle dispersion 1] used in Example 1 was changed to the following [resin fine particle dispersion 67]. The physical properties of the obtained toner are shown in Table 2, and the evaluation results are shown in Table 3.
-Preparation of resin fine particle dispersion 6-
The above-mentioned crystalline polyester resin 1 and non-crystalline polyester resin 1 were coarsely pulverized with a hammer mill to prepare a resin particle dispersion.
50 parts by weight of ethyl acetate and 110 parts by weight of IPA were added to a ₂ L separable flask equipped with an anchor blade for supplying stirring power, a reflux device, and a decompression device using a vacuum pump, and N ₂ was fed at a rate of 0.2 L / m. The air in the system was replaced with N ₂ . Next, 20 parts by weight of the crystalline polyester resin 1 and 180 parts by weight of the amorphous polyester resin 1 were slowly added while being heated to 60 ° C. by an in-system oil bath apparatus, and dissolved while stirring. Next, 20 parts by weight of 10% ammonia water was added thereto, and then 460 parts by weight of ion-exchanged water was added thereto at a rate of 9.6 g / m while stirring using a metering pump. Emulsification was completed when the emulsification system was milky white and the stirring viscosity was reduced.
Next, the pressure was reduced to -700 Torr, and the mixture was stirred for 40 minutes while stirring. Further, 50 parts by weight of pure water at 60 ° C. was added thereto, and stirring was continued for 20 minutes under reduced pressure. When the reflux amount reached 210 parts by weight, this was taken as the end point, and overheating was stopped and the mixture was cooled to room temperature while stirring. The particle size of the obtained resin particles was measured using a laser diffraction / scattering particle size distribution analyzer (LA-920, manufactured by Horiba, Ltd.). The average particle size of the obtained resin fine particles was 260 nm.

[Comparative Example 4]
In Example 1, a toner was obtained in the same manner as in Example 1 except that [Prepolymer 1] and a ketimine compound were not contained. The toner contained no modified polyester and was a toner that was not stretched or crosslinked. The physical properties of the obtained toner are shown in Table 2, and the evaluation results are shown in Table 3.

(Evaluation item)
1) Low-temperature fixability After outputting 10,000 sheets of 5% image area chart using the obtained two-component developer and an evaluator, the temperature of the fixing unit is changed by 5 ° C., and an image is output to fix the image. Was measured. Ricoh full color PPC paper type 6000 was used as the transfer paper.
By changing the fixing temperature of the fixing machine, a print image having an image density of 1.2 by X-Rite 938 was obtained. The lowest temperature at which no cold offset occurred was evaluated as the minimum fixing temperature. Cold offset is an offset toner in which the toner does not melt sufficiently at a low temperature and adheres to the fixing member (belt, roller), not the paper, contaminates the fixing member, rotates once, and adheres to the fixing member on the next paper. Is an image defect that reattaches and stains a portion where an image should not be originally formed.
The evaluation results are shown as follows.
A: 110-120 ° C
○: 125-130 ° C
Δ: 135-140 ° C.
×: 140 ° C or higher

2) Heat-resistant storage stability Weigh 10 g of toner, put it in a 20 ml glass container, tap the glass bottle 100 times with a tapping machine, and leave it in a thermostatic chamber set at 55 ° C. and 80% humidity for 100 hours. The penetration was measured with a penetration tester (conditions described in the Nikka Engineering Manual). From the good one, ◎: 20 mm or more, ◯: 15 mm or more and less than 20 mm, Δ: 10 mm or more to less than 15 mm, x: less than 10 mm.

3) Photoconductor contamination Using the obtained two-component developer and an evaluation machine, an image area ratio 20% chart, BW mode, 100 Print / Job (interval 5 minutes) 5,000 sheets / day, total output of 50,000 sheets The test was conducted. Evaluation environmental conditions were carried out in an office high temperature and high humidity environment of 27 ° C. and 80%. Ricoh full color PPC paper type 6200 was used as the transfer paper.
The photoreceptor at that time was taken out, and the photoreceptor filming (adhered foreign matter) was observed as surface irregularities. Using a full-color confocal microscope C130, which is a confocal microscope manufactured by Lasertec, the surface roughness Ra in a 500 μm square region was evaluated according to the following criteria.
◎ Less than 0.05μm ○ 0.05μm or more and less than 0.09μm △ 0.09μm or more and less than 0.13μm × 0.13μm or more

(About Fig. 3 and Fig. 4)
DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Transfer apparatus, Primary transfer apparatus 3 Sheet conveyance belt 4 Intermediate transfer body 5 Secondary transfer apparatus 6 Paper feed apparatus 7 Fixing apparatus 8 Photoconductor cleaning apparatus 9 Intermediate transfer body cleaning apparatus s Sheet T Tandem type image forming apparatus

(About Figure 5)
DESCRIPTION OF SYMBOLS 10 Intermediate transfer bodies 14, 15, 16 Support roller 17 Intermediate transfer cleaning device 18 Image forming means 20 Tandem image forming device 21 Exposure device 22 Secondary transfer device 23 Roller 24 Secondary transfer belt 25 Fixing device 26 Fixing belt 27 Pressure roller 28 Sheet reversing device 30 Document base 32 Contact glass 33 First traveling body 34 Second traveling body 35 Imaging lens 36 Reading sensor 40 Photosensitive body 42 Paper feed roller 43 Paper bank 44 Paper feed cassette 45 Separating roller 46 Paper feed path 47 Conveyance Roller 48 Paper feed path 49 Registration roller 50 Paper feed roller 51 Manual feed tray 52 Separation roller 53 Manual feed path 55 Switching claw 56 Ejection roller 57 Ejection tray 100 Copying apparatus main body 200 Paper feed table 300 Scanner 400 Automatic document feeder (FIG. 6) about)
40 Photoconductor 60 Charging device 61 Developing device 62 Primary transfer device 63 Photoconductor cleaning device 64 Static eliminating device

JP 2008-276269 A

Claims (15)

In a toner containing at least a binder resin, a colorant, and a release agent, the toner has a core-shell structure having a core inside and a shell on the surface of the core, and at least crystalline in the core part A softening temperature ST (° C.) of the shell layer measured by an SPM probe with a built-in heater and a polyester resin, an amorphous polyester resin, a colorant, a release agent, and a softening temperature CT (° C. of the inner core portion) ) Shows the following relationship:
1.1 ≦ ST / CT ≦ 2.5 The toner according to claim 1, wherein SL and TL have the following relationship, where SL is the thickness of the shell layer and TL is the maximum diameter of the toner particles.
0.01 ≦ SL / TL ≦ 0.20   The toner according to claim 1, wherein the non-crystalline polyester resin contains a modified polyester resin.   In the toner, oil droplets of an organic solvent in which a toner composition containing a polyester prepolymer that becomes a crystalline polyester resin, a colorant, a release agent, and an amorphous polyester resin is dispersed in an aqueous medium, and an extension reaction and / or The toner according to claim 1, wherein the toner is a particle formed by a crosslinking reaction.   The toner according to claim 4, wherein the polyester prepolymer is a polymer having a site capable of reacting with a compound having an active hydrogen group.   The toner according to claim 4, wherein the toner composition further contains an amorphous polyester.   The toner according to claim 1, wherein the shell layer of the toner contains at least a vinyl resin.   The toner according to claim 1, wherein an average circularity E of the toner is 0.93 to 0.99.   The toner according to claim 1, wherein the toner has a circularity SF-1 value of 100 to 150 and a circularity SF-2 value of 100 to 140.   The weight average particle diameter D4 of the toner particles is 2 to 7 μm, and the ratio D4 / Dn of the weight average particle diameter D4 to the number average particle diameter Dn is 1.25 or less. The toner according to any one of the above.   A two-component developer comprising at least the toner according to claim 1 and a carrier.   A toner for replenishment comprising at least the toner according to claim 1 and a carrier.   An image forming apparatus using the toner according to claim 1. An image forming apparatus comprising the fixing device using the toner according to claim 1 and fixing a visible image on a recording medium by heat and pressure, wherein at least four or more development colors are different. and a tandem type developing system arranged a developing unit in series, the system speed is 500~2500mm / sec, and pressing surface pressure of the fixing medium, and characterized by a 5N / cm ² ~90N / cm ² A color image forming apparatus.   11. A process cartridge that integrally supports a latent image carrier and at least developing means and is detachable from an image forming apparatus main body, the developing means holds toner, and the toner is defined in any one of claims 1 to 10. A process cartridge characterized by being a toner.