JP2002357923A - Electrostatic charge image developing toner, method for producing the same and image forming method using the toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner which ensures high saturation of blue (cyan), high transmittance of an image and high image density, reduces fog under the conditions of high temperature and high humidity, attains excellent uniformity of halftone and is less liable to cause diffusion of fine dots and to provide a method for producing the toner and an image forming method using the toner. SOLUTION: In the electrostatic charge image developing toner containing toner particles obtained by forming colored particles containing a bonding resin and a colorant in an aqueous medium and mixing the colored particles with metal oxide particles, the colorant has metal-free phthalocyanine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic image, a method for producing the toner, and an image forming method using the toner.

[0002]

2. Description of the Related Art Today, an electrostatic latent image developing method represented by an electrophotographic method is a high-quality method for obtaining a high-speed and high-quality image stably in a printer, a copying machine, a facsimile machine or the like. Although widely used for the formation method, some problems still remain.

For example, conventionally, in a toner prepared by a pulverization method, the material dispersed in the toner is unevenly present on the fracture surface, the surface properties of the toners are hardly constant, and the dispersion in the transfer process is reduced. This has a problem that the color reproducibility is likely to occur and the color reproducibility as a color image is likely to be reduced.

On the other hand, it is desired to reduce the particle size of the toner for developing an electrostatic latent image from the viewpoint of improving image quality. In recent years, polymerization toners have been actively developed as a method for producing small particle size toners.
The polymerized toner is prepared by associating or salting-out, aggregating, and fusing the resin particles and, if necessary, the colorant particles to prepare an irregular shaped toner, or dispersing a radical polymerizable monomer and a colorant. Then, there is a method in which droplets are dispersed in an aqueous medium or the like so as to have a desired toner particle diameter, and suspension polymerization is performed.

[0005] However, the toner particles produced by applying the suspension polymerization method can form a toner having a spherical and uniform surface property, so that the uniformity among the toners is high, but the shape of the toner particles is spherical. Therefore, the adhesion to the latent image carrier is increased, so that there is a problem that the transferability is easily reduced.

Therefore, it is considered that the resin particles produced by treating a resin particle polymerized in an aqueous medium containing a surfactant with a coagulant having a concentration equal to or higher than the critical coagulation concentration of the resin particle and an organic solvent infinitely soluble in water. Japanese Patent Application Laid-Open No. H11-194540 discloses a characteristic non-spherical particle.

In the technique described above, the use of a divalent or trivalent metal salt as an aggregating agent provides an excellent uniformity of shape and uniformity of charge amount, and an image with high sharpness can be obtained.
The presence of the divalent or trivalent metal salt raises the Krafft point of the surfactant and forms a sparingly soluble precipitate in water. This precipitate exists in a state where it adheres to the toner even after the colored particles, that is, the toner is separated from the aqueous medium, and fog easily occurs under high temperature and high humidity, and transferability tends to decrease (reduction in image density). ).

[0008] In order to achieve particularly high image quality, it is preferable to prepare the toner particles with a small particle size and to make the shape of the toner particles uniform. However, such toner particles have the following problems. There are problems such as uniformity of halftone, generation of dust of fine dots, reduction of transfer rate, filming of a transfer body, and the like, and a solution to the above problems has been demanded.

In the conventional toners for developing an electrostatic image, blue-colored toners used as full-color coloring agents include C.I. I. Pigment Blue 15: 3
Is generally used because it is advantageous in terms of cost, color characteristics, and light fastness.

However, C.I. I. Pigment Blue 1
The toner using 5: 3 has a problem in environmental stability and dispersibility of a colorant.
There was a problem in the transparency of the image and the like.

Regarding the problem of the blue color saturation of the blue image, see, for example, Japanese Patent Application Laid-Open Nos.
No. 6277 discloses a toner using a metal-free phthalocyanine. However, since the crystal form of the metal-free phthalocyanine is generally α-type and has a brownish tinge, a bright blue (cyan) color cannot be obtained. Was.

Japanese Patent Application Laid-Open No. 11-7160 discloses toner particles containing a copper phthalocyanine pigment having a content of α-type crystal of 7% or less and at least a binder resin. Conventional pulverized toner, for example,
In the case of toner using the pulverized material obtained by pulverizing with a jet mill or other means, even when using β-type, most of the toner easily transitions to α-type due to the mechanical impact force of the pulverization. It was not enough.

[0013]

SUMMARY OF THE INVENTION It is an object of the present invention to provide blue (cyan) saturation, image transparency, and high image density.
Fog under high-temperature and high-humidity conditions is reduced, the uniformity of halftone is excellent, and the generation of fine dot dust is small, and the toner for developing an electrostatic image, the method for producing the toner, and
An object of the present invention is to provide an image forming method using the toner.

[0014]

The above objects of the present invention have been attained by the following items 1 to 9.

1. In an aqueous medium, after forming colored particles containing a binder resin and a colorant, a toner for electrostatic image development containing toner particles obtained by adding and mixing metal oxide particles to the colored particles, A toner for developing an electrostatic image, wherein the colorant comprises a metal-free phthalocyanine.

2. Wherein the metal-free phthalocyanine contains 70% by mass or more of β-type metal-free phthalocyanine and 30% by mass or less of α-type metal-free phthalocyanine.
3. The toner for developing an electrostatic image according to item 1.

3. (1) The metal-free phthalocyanine contains 85% by mass or more of β-type metal-free phthalocyanine and 15% by mass or less of α-type metal-free phthalocyanine.
3. The toner for developing an electrostatic image according to item 1.

4. 4. The electrostatic image developing toner according to any one of items 1 to 3, wherein the toner contains 10 to 5000 ppm of a phthalimide derivative or a phthalonitrile derivative.

5. The toner contains toner particles having a number average particle diameter of 2 to 6 μm, and 6 to 12% by mass of a metal-free phthalocyanine, and the metal-free phthalocyanine has an average Feret horizontal diameter of 10 to 30 nm, 5. The electrostatic image developing toner according to any one of items 1 to 4, wherein the toner is dispersed in the toner particles such that a coefficient of variation of the toner is 30% or less.

6. 5. The method for developing an electrostatic charge image according to any one of items 1 to 4, wherein toner particles are manufactured through the above-described steps (1) to (3). Manufacturing method of toner.

7. 7. The method for producing a toner for developing an electrostatic image according to the item 6, further comprising a step of salting out, aggregating, and fusing the resin particles and the metal-free phthalocyanine particles in an aqueous medium.

8. 8. The method for producing a toner for developing an electrostatic image according to the above item 6 or 7, further comprising a step of salting out, aggregating, and fusing the composite resin particles obtained by the multistage polymerization method and the metal-free phthalocyanine particles. .

9. A developing roll and a toner supply member for supplying toner on the development roll, supplying a non-magnetic toner from the toner supply member to the development roll, and performing development using a toner layer formed on the development roll. 9. The image forming method using a one-component developing device, wherein the non-magnetic toner is the toner for developing an electrostatic image according to any one of 1 to 5 or the electrostatic image developing according to any one of 6 to 8. An image forming method using the toner for developing an electrostatic image described in the method for producing a toner for use in an image forming apparatus.

Hereinafter, the present invention will be described in detail. As a result of various studies on the means for solving the above problems, the present inventors formed colored particles containing a binder resin and a colorant in an aqueous medium, and then added metal oxide particles to the colored particles. By using toner particles obtained by mixing and using metal-free phthalocyanine as a colorant, blue (cyan) saturation, image transparency, image density are high, and fog under high temperature and high humidity conditions is reduced. It has been found that a toner for developing an electrostatic charge image which is reduced, has excellent halftone uniformity, and has little occurrence of dust of fine dots can be obtained.

In particular, with respect to the bluish (cyan) color, unlike the conventionally known pulverization method using a jet mill or Henschel mixer, the toner for developing an electrostatic image of the present invention has toner particles in an aqueous medium. It is believed that the formation is the reason why the significant improvement in saturation was obtained.

The metal-free phthalocyanine according to the present invention will be described. The metal-free phthalocyanine according to the present invention is a phthalocyanine containing no central metal and represented by the following structural formula (1), and details thereof will be described later, but usually o-phthalodinitrile, 1,3-diiminoiso Indoline to Na
₂ S and hydroquinone and various base is synthesized by condensation reductively as catalyst.

[0027]

Embedded image

The toner of the present invention preferably contains 70% or more of β-type metal-free phthalocyanine and 30% or less of α-type metal-free phthalocyanine as a composition of metal-free phthalocyanine from the viewpoint of sufficiently bringing out brightness and vividness. More preferably, the content of the β-type metal-free phthalocyanine is 85% by mass or more, and the content of the α-type metal-free phthalocyanine is 15% by mass or less.

As a method for specifying the above-mentioned α-type and β-type metal-free phthalocyanine, when the phthalocyanine is contained in the toner, ultrasonic waves are applied to the toner in methanol to remove metal oxide particles. After that, a method of dissolving in tetrahydrofuran, separating inorganic phthalocyanine particles by centrifugation, and then performing X-ray analysis to identify the structure is mentioned. When the phthalocyanine compound is used alone, the X-ray analysis may be performed as described above.

Further, α-form and β-form in metal-free phthalocyanine
The content of the mold was measured by X-ray diffraction measurement of a metal-free phthalocyanine sample, and 2θ = 15.6 showing the characteristic of α-form was obtained.
°, 16.6 °, and 2θ = 18.1 indicating the characteristics of β-form
° and 18.4 °, the peak areas at diffraction angles of Sα /
When Sβ is set, it can be calculated from Sα / (Sα + Sβ) × 100.

The toner of the present invention contains 10 ppm of phthalimide and phthalonitrile from the viewpoint of adjusting the bluish color.
Preferably, the content is in the range of 40 to 2500 ppm. Here, phthalimide and phthalonitriles may be unsubstituted or include phthalimide and phthalonitrile which may have a substituent, and dimers and trimers thereof.

The phthalimide and phthalonitrile in the toner of the present invention can be easily analyzed by GC-MS after dissolving the toner in dichlorotoluene.

From the viewpoint of obtaining a sufficient image density using the toner for developing an electrostatic image of the present invention (hereinafter also referred to as toner), the content of the metal-free phthalocyanine particles in the toner is 3%.
It is preferably from 10% by mass to 10% by mass, and more preferably from 4% by mass to 8% by mass.

As a method for synthesizing the metal-free phthalocyanine according to the present invention, for example, it can be synthesized by heating o-phthalodinitrile at a high temperature for a long time using dichlorotoluene as a solvent and a base such as cyclohexylamine as a catalyst. In German Patent No. 696,344, metal-free phthalocyanine can also be obtained by heating o-phthalodinitrile in trichlorobenzene with hydroquinone, glycerol or the like as a catalyst.

Further, a preferred production method is disclosed in
000-129153.
That is, it is a method of reacting unsubstituted or substituted o-phthalodinitrile in the presence of an inorganic base and a ferrocene compound which may have a substituent in an alcohol solvent.

Examples of the alcohol solvents described above include primary alcohols such as methanol, ethanol, butanol and octanol, polyhydric primary alcohols such as ethylene glycol and diethylene glycol, and ethylene glycol monomethyl ether and ethylene glycol monoethyl ether. And cellosolve solvents such as diethylene glycol monoethyl ether, and secondary alcohols such as isopropyl alcohol. Primary alcohols exhibiting good hydrophilicity, especially ethylene glycol, in consideration of the reaction temperature and isolation and purification after the reaction, are preferred. And diethylene glycol are preferably used. In addition, the amount of the alcohol-based solvent is not problematic as long as the o-phthalodinitrile is sufficiently dissolved after the temperature is raised. The range is appropriate, preferably the range of 1: 2 to 1: 4 is optimal.

The inorganic bases preferably used include hydroxides of alkali metals such as lithium hydroxide, sodium hydroxide and potassium hydroxide, carbonates of alkali metals such as sodium carbonate and potassium carbonate, sodium sulfide, and the like. Various alkali metal salts such as alkali metal salts of low sulfur oxide compounds such as sodium sulfite and sodium hyposulfite; ammonium salts such as hydroxyammonium chloride, ammonium sulfate, ammonium carbonate and ammonium molybdate; hydrazine sulfate, hydrazine carbonate and hydrazine phosphate And the like, and alkali metal salts, particularly lithium hydroxide, sodium hydroxide and potassium carbonate are preferred.

The amount of these inorganic bases is preferably in the range of 1/20 to 1/2 mol, more preferably in the range of 1/10 to 1/4 mol, per 1 mol of o-phthalodinitrile. .

In the present invention, C.I.
I. Pigment Violet 23, for example, Chrom
mofineViolet RE (Dainichi Seika), Fas
tViolet BLD (Sanyo Dye), Fastage
n Super Violet RN (Dainippon Ink), Kayaset Violet (Nippon Kayaku), L
ionogen Violet RL (Toyo Ink), P
iigment Super Violet (Nippon Pigment), Plymo Violet FWT (Kiwa Chemical), SunltoneFast Violet RW
(Sumitomo Chemical), Indifast Violet B.4
018 (Bayer), Monolite Violet
RN (ICI), Sandorin Violet
BL (sand) or the like can be used in combination.

The toner for developing an electrostatic charge image (also referred to simply as toner) of the present invention will be described. The toner particles according to the present invention are obtained by forming colored particles containing a binder resin and a colorant in an aqueous medium, and then adding a metal oxide to the colored particles to mix the toner particles into at least a polymerizable monomer. Is polymerized in an aqueous medium.

As a method for producing the above binder resin, resin particles are prepared by polymerizing a polymerizable monomer by a suspension polymerization method, or in a solution containing an emulsion of a necessary additive (aqueous solution). Emulsion polymerization or mini-emulsion polymerization of monomers in a medium) to prepare fine resin particles, and after adding charge controllable resin particles as necessary, an organic solvent, flocculants such as salts, etc. Is preferable to be produced by a method of coagulating and fusing the resin particles.

The method for preparing resin particles and the method for producing toner particles as described above are described, for example, in JP-A-5-265252.
And JP-A-6-329947, 9-159
The method disclosed in Japanese Patent Publication No. 04-2004 can be mentioned. That is, a method of salting out, aggregating, and fusing a plurality of fine particles composed of a resin and a colorant, or a dispersion particle of a constituent material such as a resin particle and a colorant, particularly dispersing these in water using an emulsifier. After that, a coagulant having a critical coagulation concentration or more is added and salted out, and at the same time, the formed polymer itself is heated and fused at a temperature of the glass transition temperature or more to gradually grow the particle size while forming fused particles. When the target particle size is reached, a large amount of water is added to stop the particle size growth, and further heating,
The toner of the present invention can be formed by smoothing the surface of the particles while stirring, controlling the shape of the particles, and heating and drying the particles in a fluid state while keeping the particles wet. Here, a solvent such as alcohol which is infinitely soluble in water may be added together with the coagulant.

In the method for producing a toner according to the present invention, the composite resin fine particles and the colorant particles formed through the step of dissolving the crystalline substance in at least the polymerizable monomer and polymerizing the polymerizable monomer are used. It is obtained by salting out / fusing. The toner of the present invention dissolves a crystalline substance in a polymerizable monomer. The crystalline substance may be dissolved or dissolved, or may be dissolved and dissolved.

The method for producing the toner of the present invention is to salt out / fuse the composite resin fine particles obtained by the multi-stage polymerization method and the colorant particles. The multi-stage polymerization method will be described below.

<< Method for Producing Composite Resin Particles Obtained by Multistage Polymerization Method >> The method for producing a toner of the present invention comprises the following steps.

1: Multi-stage polymerization step 2: Salting-out / fusing step of salting-out / fusing the composite resin particles and colorant particles to obtain toner particles 3: Filtering out the toner particles from the dispersion system of the toner particles And
A filtration / washing step of removing a surfactant or the like from the toner particles; a drying step of drying the washed toner particles; and a step of adding an external additive to the dried toner particles.

Hereinafter, each step will be described in detail. [Multi-stage polymerization step] The multi-stage polymerization step is a polymerization method carried out to expand the molecular weight distribution of the resin particles in order to obtain a toner in which offset has been prevented. That is, in order to form phases having different molecular weight distributions in one resin particle, the polymerization reaction is performed in multiple stages, and the obtained resin particles have a molecular weight gradient from the center of the particle toward the surface layer. It is intended to be formed. For example, a method in which a high molecular weight resin particle dispersion is obtained first, and then a low molecular weight surface layer is formed by newly adding a polymerizable monomer and a chain transfer agent.

In the present invention, it is preferable to employ a multi-stage polymerization method of three-stage polymerization or more from the viewpoint of production stability and crushing strength of the obtained toner. Hereinafter, two-stage polymerization and three-stage polymerization, which are typical examples of the multi-stage polymerization, will be described. In the toner obtained by such a multi-stage polymerization reaction, those having a molecular weight as low as the surface layer are preferable from the viewpoint of crushing strength.

<Two-Step Polymerization Method> In the two-step polymerization method, a central part (nucleus) formed from a high molecular weight resin containing a crystalline substance is used.
And a method of producing composite resin particles comprising an outer layer (shell) formed of a low molecular weight resin.

The method will be described in detail. First, a crystalline substance is dissolved in a monomer to prepare a monomer solution, and the monomer solution is added to an aqueous medium (for example, an aqueous solution of a surfactant).
After the oil droplets are dispersed therein, this system is subjected to a polymerization treatment (first stage polymerization) to prepare a dispersion of high molecular weight resin particles containing a crystalline substance.

Next, a polymerization initiator and a monomer for obtaining a low molecular weight resin are added to the dispersion of the resin particles, and the monomer is subjected to a polymerization treatment (second stage polymerization) in the presence of the resin particles. Is performed to form a coating layer made of a low molecular weight resin (monomer polymer) on the surface of the resin particles.

<Three-step polymerization method> In the three-step polymerization method, a central part (nucleus) formed from a high molecular weight resin, an intermediate layer containing a crystalline substance, and an outer layer (shell) formed from a low molecular weight resin are used. This is a method for producing composite resin particles. The toner of the present invention exists as the composite resin particles as described above.

The method will be specifically described. First, a dispersion of resin particles obtained by a polymerization treatment (first-stage polymerization) according to a conventional method is added to an aqueous medium (eg, an aqueous solution of a surfactant). Along with the addition, a monomer solution obtained by dissolving a crystalline substance in a monomer is dispersed in the aqueous medium in oil droplets, and then the system is subjected to a polymerization treatment (second-stage polymerization). A coating layer (intermediate layer) made of a resin (monomer polymer) containing a crystalline substance is formed on the surface of the particles (core particles) to form a composite resin particle (high molecular weight resin-intermediate molecular weight resin). Prepare a dispersion.

Next, a polymerization initiator and a monomer for obtaining a low-molecular-weight resin are added to the dispersion liquid of the obtained composite resin particles, and the monomer is subjected to a polymerization treatment (first step) in the presence of the composite resin particles. By performing the three-stage polymerization, a coating layer made of a low-molecular-weight resin (monomer polymer) is formed on the surfaces of the composite resin particles. In the above method, the incorporation of an intermediate layer is preferable because the crystalline substance can be finely and uniformly dispersed.

One feature of the method for producing a toner according to the present invention is to polymerize a polymerizable monomer in an aqueous medium. That is, when forming resin particles (core particles) or a coating layer (intermediate layer) containing a crystalline substance, the crystalline substance is dissolved in a monomer, and the resulting monomer solution is oiled in an aqueous medium. In this method, latex particles are obtained by dispersing droplets, adding a polymerization initiator to the system, and performing a polymerization treatment.

Here, the aqueous medium refers to a medium comprising 50 to 100% by mass of water and 0 to 50% by mass of a water-soluble organic solvent. Examples of the water-soluble organic solvent include methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, tetrahydrofuran, and the like, and an alcohol-based organic solvent that does not dissolve the obtained resin is preferable.

As a polymerization method suitable for forming resin particles or a coating layer containing a crystalline substance, a crystalline substance is dissolved in an aqueous medium obtained by dissolving a surfactant having a concentration lower than the critical micelle concentration. The monomer solution dissolved in the monomer is dispersed in oil droplets using mechanical energy to prepare a dispersion, and a water-soluble polymerization initiator is added to the obtained dispersion, and the oil is dispersed in the oil droplets. A method of radical polymerization (hereinafter, referred to as a “mini-emulsion method” in the present invention) can be mentioned, and the effect of the present invention can be more exerted, which is preferable.

In the above method, an oil-soluble polymerization initiator may be used instead of or together with the water-soluble polymerization initiator.

According to the mini-emulsion method in which oil droplets are formed mechanically, unlike a normal emulsion polymerization method, a crystalline substance dissolved in an oil phase is less detached, and a resin particle or a coating layer to be formed is formed. A sufficient amount of crystalline material can be introduced into the inside.

Here, the disperser for dispersing oil droplets by mechanical energy is not particularly limited. For example, a stirrer “CLEARMIX” (M) equipped with a high-speed rotating rotor is used. -Technic Co., Ltd.), an ultrasonic disperser, a mechanical homogenizer, a Menton-Gaulin and a pressure homogenizer. Further, the dispersion particle diameter is 1
0 nm to 1000 nm, preferably 50 nm to 1 nm.
000 nm, more preferably 30 nm to 300 nm. Here, by giving a distribution to the dispersed particle diameter, the phase separation structure of the crystalline substance in the toner particles, that is, the Feret diameter, the shape coefficient, and the variation coefficient thereof may be controlled.

Incidentally, as other polymerization methods for forming the resin particles containing the crystalline substance or the coating layer, known methods such as an emulsion polymerization method, a suspension polymerization method and a seed polymerization method may be employed. . In addition, these polymerization methods can also be employed to obtain resin particles (core particles) or coating layers constituting the composite resin particles, which do not contain a crystalline substance.

The particle diameter of the composite resin particles obtained in this polymerization step is 10 n as a mass average particle diameter measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.).
It is preferably in the range of m to 1000 nm.

The glass transition temperature (Tg) of the composite resin particles is preferably in the range of 48 to 74 ° C., more preferably 52 to 64 ° C. The softening point of the composite resin particles is preferably in the range of 95 to 140 ° C.

The toner of the present invention is obtained by forming a resin layer formed by fusing the resin particles on the surfaces of the resin and the colored particles by a salting out / fusion method. explain.

[Salt-out / fusion step] In the salt-out / fusion step, the composite resin particles obtained by the multi-stage polymerization step and the colorant particles are subjected to salt-out / fusion (the salt-out / fusion step). At the same time) to obtain irregular (non-spherical) toner particles.

The term “salting out / fusion” means that salting out (aggregation of particles) and fusion (loss of interface between particles) occur simultaneously, or that salting out and fusion occur simultaneously. In order to simultaneously carry out the salting-out and the fusion, it is necessary to agglomerate the particles (composite resin particles, colorant particles) under a temperature condition equal to or higher than the glass transition temperature (Tg) of the resin constituting the composite resin particles. .

In this salting-out / fusion step, together with the composite resin particles and the colorant particles, internal additive particles (fine particles having a number average primary particle diameter of about 10 to 1000 nm) such as a charge controlling agent are salted out / fused. May be. Also, the colorant particles
The surface may be modified, and a conventionally known surface modifier may be used.

[Aging Step] The aging step is a step subsequent to the salting-out / fusing step. After the resin particles are fused, the temperature is kept near the melting point of the crystalline substance, preferably at a melting point of ± 20 ° C. In this step, the crystalline substance is phase-separated by continuing the stirring at an intensity of. In this step, it is possible to control the Feret diameter and the shape coefficient of the crystalline substance and the coefficient of variation thereof.

The colorant particles are subjected to salting out / fusion treatment in a state of being dispersed in an aqueous medium. The aqueous medium in which the colorant particles are dispersed is preferably an aqueous solution in which a surfactant is dissolved at a concentration equal to or higher than the critical micelle concentration (CMC).

The disperser used for dispersing the colorant particles is not particularly limited, but is preferably a stirrer “CLEARMIX (CLEARM) equipped with a high-speed rotating rotor.
MIX) "(manufactured by M Technique Co., Ltd.), an ultrasonic disperser, a pressure disperser such as a mechanical homogenizer, a Menton-Gaulin, a pressure type homogenizer, and a medium disperser such as a Getzman mill and a diamond fine mill.

In order to carry out salting out / fusion of the composite resin particles and the colorant particles, a salting-out agent having a critical coagulation concentration or more (aggregating agent) is added to the dispersion in which the composite resin particles and the colorant particles are dispersed. ) And heating the dispersion above the glass transition temperature (Tg) of the composite resin particles.

The temperature range suitable for salting out / fusing is (Tg + 10 ° C.) to (Tg + 50 ° C.), and particularly preferably (Tg + 15 ° C.) to (Tg + 40 ° C.). Further, in order to effectively perform the fusion, an organic solvent which is infinitely soluble in water may be added.

In the present invention, after the resin particles and the colorant are salted out, aggregated and fused in an aqueous medium to obtain colored particles (in the present invention, referred to as toner particles), the toner particles are removed from the aqueous medium. The separation is preferably performed at a temperature equal to or higher than the Kraft point of the surfactant present in the aqueous medium, and more preferably from the Kraft point to (Kraft point +
(20 ° C.).

The above-mentioned Krafft point is the temperature at which the aqueous solution containing the surfactant starts to become cloudy, and the Krafft point is measured as follows.

<< Measurement of Kraft Point >> A solution was prepared by adding an actually used amount of a coagulant to an aqueous medium used in the steps of salting out, coagulation, and fusion, ie, a surfactant solution. For 5 days. The solution was then heated gradually with stirring until it became clear. The temperature at which the solution became clear is defined as the Krafft point.

From the viewpoint of suppressing excessive charging of the toner particles and imparting a uniform charging property, in particular, in order to stabilize and maintain the charging property with respect to the environment, the toner for developing an electrostatic image of the present invention comprises: The metal elements described above (in the form of metal,
Metal ions, etc.) in the toner of 250 to 20
The content is preferably 000 ppm, more preferably 800 to 5000 ppm.

In the present invention, the total value of the divalent (trivalent) metal element used for the coagulant and the monovalent metal element added as the coagulation terminator described later is 350 to 35,000 pp.
m is preferable. The measurement of the residual amount of metal ions in the toner is performed using a fluorescent X-ray analyzer "System 3270"
It can be determined by measuring the intensity of fluorescent X-rays emitted from a metal species of a metal salt used as a coagulant (for example, calcium derived from calcium chloride) using [Rigaku Denki Kogyo]. As a specific measuring method, a plurality of toners having a known content ratio of the coagulant metal salt are prepared, and 5 g of each toner is pelletized, and the content ratio (mass ppm) of the coagulant metal salt and the metal type of the metal salt are determined. The relationship (calibration curve) with the fluorescent X-ray intensity (peak intensity) from the sample is measured. Next, the toner (sample) whose content ratio of the coagulant metal salt is to be measured is similarly pelletized, and the fluorescent X-ray intensity from the metal species of the coagulant metal salt is measured. Quantity "can be determined.

[Filtration / Washing Step] In this filtration / washing step, a filtration treatment for filtering the toner particles from the dispersion system of the toner particles obtained in the above step and a filtration treatment for the toner particles (cake-like) are performed. Washing treatment for removing extraneous substances such as surfactants and salting-out agents from the aggregates). Here, the filtration method is not particularly limited, such as a centrifugal separation method, a reduced pressure filtration method using a Nutsche method, a filtration method using a filter press, or the like.

[Drying Step] This step is a step of drying the washed toner particles.

The dryer used in this step includes a spray dryer, a vacuum freeze dryer, a reduced pressure dryer and the like, a stationary shelf dryer, a movable shelf dryer, a fluidized bed dryer, a rotary bed dryer and the like. It is preferable to use a type dryer, a stirring type dryer and the like.

The moisture content of the dried toner particles is preferably 5% by mass or less, more preferably 2% by mass or less. When the dried toner particles are aggregated by a weak attraction between the particles, the aggregate may be crushed. Here, as the crushing device, a mechanical crushing device such as a jet mill, a Henschel mixer, a coffee mill, and a food processor can be used.

The toner of the present invention forms composite resin particles in the absence of a colorant, adds a dispersion of the colorant particles to a dispersion of the composite resin particles, and combines the composite resin particles with the colorant particles. It is preferably prepared by salting out / fusing.

As described above, by preparing the composite resin particles in a system in which no colorant is present, the polymerization reaction for obtaining the composite resin particles is not hindered. Therefore, according to the toner of the present invention, the excellent offset resistance is not impaired, and the fixing device is not stained or the image is not stained due to the accumulation of the toner.

In addition, as a result of the reliable polymerization reaction for obtaining the composite resin particles, no monomer or oligomer remains in the obtained toner particles. No unpleasant odor is generated in the heat fixing step.

Further, the surface characteristics of the obtained toner particles are uniform and the charge amount distribution is sharp, so that an image having excellent sharpness can be formed for a long period of time. According to such a toner having a uniform composition, molecular weight, and surface characteristics among toner particles, good adhesion (high fixing strength) to an image support is maintained in an image forming method including a fixing step by a contact heating method. Meanwhile, the offset resistance and the anti-winding property can be improved, and an image having an appropriate gloss can be obtained.

Next, the shape of the toner of the present invention will be described in detail. The toner particles used in the present invention have developability,
In order to obtain fine line reproducibility and stable cleaning properties, the coefficient of variation of the shape factor is preferably 16% or less,
More preferably, the number variation coefficient in the number particle size distribution is 27% or less.

The shape factor of the toner of the present invention will be described. In the toner of the present invention, the proportion of toner particles having a shape coefficient in the range of 1.2 to 1.6 is 65% by number or more, the coefficient of variation of the shape coefficient is 16% or less, and the number in the number particle size distribution is The coefficient of variation is 27% or less. Here, the shape factor of the toner of the present invention is represented by the following equation, and indicates the degree of roundness of the toner particles.

Shape factor = ((maximum diameter / 2) ² × π) / projected area Here, the maximum diameter is defined as a parallel image when a projected image of a toner particle on a plane is sandwiched between two parallel lines. Means the width of the particle at which the distance between the particles becomes maximum. The projection area refers to the area of the projected image of the toner particles on the plane. In the present invention, the shape factor can be determined by taking a photograph in which the toner particles are magnified 2,000 times with a scanning electron microscope, and then referring to the “SCCANNING IMAGE ANALYZE” based on the photograph.
R "(manufactured by JEOL Ltd.) was used to analyze photographic images. In this case, the shape factor of the present invention was measured by using the above formula using 100 toner particles.

The variation coefficient of the shape factor of the toner particles will be described. “Variation coefficient of shape coefficient” which is one variable indicating the uniform shape of the toner particles is calculated from the following equation.

Coefficient of variation of toner shape coefficient = (S1 /
K) × 100 (%) In the formula, S1 represents a standard deviation of the shape factor of 100 toner particles, and K represents an average value of the shape factor.

As a basic condition for achieving high image quality, the variation coefficient of the shape factor of the toner particles according to the present invention is as follows.
The toner of 16% or less is preferable, but the variation coefficient of the shape factor is preferably 14% or less in order to further promote higher image quality.

In order to uniformly control the shape factor of the toner and the variation coefficient of the shape factor without variation in lots,
In the step of preparing (polymerizing) the resin particles (polymer particles) constituting the toner of the present invention and fusing and controlling the shape of the resin particles, the characteristics of the toner particles (colored particles) being formed are appropriately monitored and monitored. The end time of the process is determined.

The number particle size distribution and the number variation coefficient of the toner of the present invention will be described. The number particle size distribution and the number variation coefficient of the toner according to the present invention are measured with a Coulter Counter TA-II or a Coulter Multisizer (manufactured by Coulter Corporation). In the present invention, a Coulter Multisizer was used and connected to an interface (manufactured by Nikkaki Co., Ltd.) for outputting a particle size distribution and a personal computer. The aperture used in the Coulter Multisizer is 100 μm
The particle size distribution and the average particle size were calculated by measuring the volume diameter and the number diameter of 2 μm or more using the above. The number particle size distribution represents the relative frequency of the toner particles with respect to the particle size, and the number average particle size refers to the cumulative 5 in the number particle size distribution.
It represents a diameter of 0%, that is, Dn50.

The number variation coefficient in the number particle size distribution of the toner is calculated from the following equation. Number variation coefficient = [S / Dn] × 100 (%) where S represents a standard deviation in the number particle size distribution, and Dn
Indicates a number average particle size (μm).

The number variation coefficient of the toner of the present invention is preferably 27% or less, more preferably 25% or less. By adjusting the number variation coefficient to 27% or less, the gap of the transferred toner layer is reduced, the fixability is improved, and the offset is less likely to occur. Further, it is possible to obtain favorable effects such as a sharp charge amount distribution, a high transfer efficiency, and an improvement in image quality.

The method of controlling the number variation coefficient is not particularly limited. For example, a method of classifying toner particles by wind force can be used. However, in order to reduce the number variation coefficient, classification in a liquid is effective. It is a target. As a method for classification in the liquid, there is a method in which a centrifugal separator is used, the number of rotations is controlled, and the toner particles are separated and collected according to a sedimentation velocity difference caused by a difference in toner particle diameter.

The inventors of the present invention have focused on the minute shapes of the individual toner particles, and as a result, the shape of the corners of the toner particles has changed and become round inside the developing device. Promoted the burying of the external additive, and decreased the change in the amount of charge, the fluidity, and the stability of transportation. When electric charge is applied to toner particles by frictional charging, it is presumed that the external additive tends to be buried particularly at corners, and the toner particles are likely to be non-uniformly charged. That is, the ratio of toner particles having no corners is set to 50% by number or more,
By using toner composed of toner particles whose number variation coefficient in the number particle size distribution is controlled to 27% or less, it is possible to form a high-quality image over a long period of time with excellent developability and fine line reproducibility. Was found.

Further, it has been found that even when the toner is made to have a specific shape and the shape is made uniform, the external additive does not bury, and the charge amount distribution becomes sharp. That is, the percentage of toner particles having a shape coefficient in the range of 1.2 to 1.6 is 65% by number or more, and the variation coefficient of the shape coefficient is 16%.
It has also been found that the use of the following toners makes it possible to form a high quality image over a long period of time with excellent developability and fine line reproducibility.

The toner particles having no corners in the toner of the present invention will be described. Here, the toner particles having no corners refer to toner particles having substantially no protrusions where charges are concentrated or protrusions which are easily worn by stress, that is, as shown in FIG. When the major axis of the toner particle T is L, a circle C having a radius (L / 10) is rolled inward while being in contact with the peripheral line of the toner particle T at one point. The case where the toner does not substantially protrude outside the toner T is referred to as “toner particles having no corners”.
“Cases that do not substantially protrude” refer to cases where there are no more than one protrusion having a protruding circle.

The term "major axis of toner particles" refers to the width of a particle at which the distance between the parallel lines becomes maximum when the projected image of the toner particles on a plane is sandwiched between two parallel lines. FIGS. 7B and 7C show projected images of toner particles having corners, respectively.

The measurement of the toner having no corners was performed as follows. First, a photograph in which the toner particles are enlarged by a scanning electron microscope is taken, and further enlarged to obtain a 15,000-fold photographic image. Next, the presence or absence of the corners is measured for this photographic image. This measurement was performed for 1000 toner particles.

In the toner of the present invention, the proportion of toner particles having no corners is preferably at least 50% by number, more preferably at least 70% by number. When the ratio of the toner particles having no corners is 50% by number or more, it is difficult to generate fine particles due to stress with the developer conveying member, and it is possible to suppress so-called contamination on the surface of the developer conveying member. As a result, the charge amount distribution is sharpened, the chargeability is stabilized, and effects such as good image quality can be formed over a long period are amplified.

The method for obtaining a toner having no corners is not particularly limited. For example, as described above, as a method of controlling the shape coefficient, a method of spraying toner particles into a hot air flow, a method of repeatedly applying mechanical energy by an impact force in a gas phase, or a method of dissolving a toner It can be obtained by adding to a solvent that does not contain and giving a swirling flow.

In the toner according to the present invention, when the particle size of the toner particles is D (μm), the natural logarithm lnD
Is plotted on the horizontal axis, and in the histogram showing the number-based particle size distribution obtained by dividing the horizontal axis into a plurality of classes at intervals of 0.23, the relative frequency (m1) of the toner particles included in the most frequent class
It is preferable that the toner has a sum (M) of 70% or more of the relative frequency (m2) of the toner particles included in the class having the second highest frequency after the mode.

When the sum (M) of the relative frequency (m1) and the relative frequency (m2) is 70% or more, the dispersion of the particle size distribution of the toner particles is narrowed. Thus, the occurrence of selective development can be reliably suppressed.

In the present invention, the histogram showing the number-based particle size distribution is obtained by plotting a natural logarithm lnD (D: particle size of individual toner particles) in a plurality of classes (0 to 0) at intervals of 0.23.
0.23: 0.23 to 0.46: 0.46 to 0.69:
0.69 to 0.92: 0.92 to 1.15: 1.15
1.38: 1.38 to 1.61: 1.61 to 1.84:
1.84 to 2.07: 2.07 to 2.30: 2.30 to
2.53: a histogram showing the number-based particle size distribution divided into 2.53 to 2.76..., Which is a particle size data of a sample measured by a Coulter Multisizer according to the following conditions. Is transferred to a computer via an I / O unit, and the computer creates the program using a particle size distribution analysis program.

[Measurement conditions] 1: Aperture: 100 μm 2: Sample preparation method: Electrolyte [ISOTON II (manufactured by Coulter Scientific Japan)] 50-1
An appropriate amount of a surfactant (neutral detergent) is added to 00 ml and stirred, and 10 to 20 mg of a measurement sample is added thereto. This system is prepared by subjecting it to a dispersion treatment with an ultrasonic disperser for 1 minute.

Next, the particle size of the toner of the present invention will be described. The particle size of the toner used in the present invention is 2 to 9 μm in number average particle size, preferably 4.0 to 8.5 μm, and more preferably 4.5 to 8 μm. This particle size can be controlled by the concentration of the coagulant (salting agent), the amount of the organic solvent added, the fusing time, and the composition of the polymer in the method for producing the toner.

When the number average particle size is 2 to 9 μm, the transfer efficiency is increased, the halftone image quality is improved, and the image quality of fine lines and dots is improved. The calculation of the particle size distribution of the toner and the measurement of the number average particle size are performed using a Coulter Counter TA.
-II, Coulter Multisizer (both from Coulter), SLAD1100 (Shimadzu Corporation laser diffraction particle size analyzer) and the like. In the present invention, measurement and calculation are performed using a Coulter Multisizer, an interface for outputting a particle size distribution (manufactured by Nikkaki Co., Ltd.), and a personal computer connected.

The toner particles of the toner for developing an electrostatic image of the present invention preferably have a binder resin layer forming toner particles and metal-free phthalocyanine particles used as a colorant having a sea-island structure.

From the viewpoint of producing toner particles in which the binder resin and the metal-free phthalocyanine exhibit a sea-island structure, after passing through the steps of preparing colored particles and diluting and dispersing the water-free paste of metal-free phthalocyanine in an aqueous medium. It is preferable to disperse metal-free phthalocyanine in the binder resin.

The reason for this is that in the conventionally known process for producing an organic pigment, the pigment is washed and purified by using water, and then filtered, dried and pulverized after being wetted with water. It becomes a body organic pigment. However,
By performing drying after filtration, strong agglomeration occurs, and it is not possible to easily downsize to primary particles by physical pulverization.

Therefore, by performing a dispersion treatment in an aqueous surfactant solution at the stage of the water-wet pigment paste before drying, it is possible to obtain a finely dispersed state with almost no aggregation of the pigment particles. Further, as the water-wet pigment paste, a water-wet pigment paste after milling treatment such as salt milling or solvent milling can also be used.Especially for applications requiring fine pigment particles, after salt milling, the paste is not dried. By performing the surface treatment of the present invention with a water wet paste, the modifying effect can be enhanced. Here, the salt milling generally refers to a process of making the pigment finer by milling the ground sodium chloride and the pigment in diethylene glycol. Also,
Solvent milling is a process in which a crystal of metal-free phthalocyanine particles is β-
This is a processing method for controlling to a mold, performing a process for uniforming the particle size, and controlling to a desired crystallinity.

In the present invention, reproduction of a secondary color and O
From the viewpoint of improving HP sheet permeability and preventing aggregation of pigment particles due to concentration, the solid content of the water-wet paste is preferably from 15 to 75% by mass, particularly preferably from 17 to 3%.
5% by mass.

Here, the solid content means the mass% of the metal-free phthalocyanine particles in the water-wet pigment paste.

Further, from the viewpoint of enhancing the transparency of the OHP image, the metal-free phthalocyanine according to the present invention has an average ferrite horizontal diameter of 5 nm in an island portion formed by a single particle or an aggregate in the toner particles of the present invention. It is preferably adjusted to 80 nm, particularly preferably 10 nm to 30 nm.
nm. The dispersion is preferably adjusted so that the variation coefficient of the horizontal diameter of the ferrite is 30% or less, and particularly preferably 25% or less.

[0117] The Feret horizontal diameter represents the horizontal length of the toner particles when the toner particles are arbitrarily placed horizontally, and the Feret horizontal diameter of the metal-free phthalocyanine particles (metal-free phthalocyanine particles). Includes the horizontal diameter of the island formed by a single particle or an aggregate) is the horizontal length of each island existing inside the toner particles placed in an arbitrary state on the horizontal as described above. Is represented.

Further, from the viewpoint of increasing the transmittance by reducing the light scattering of the OHP image by making the size of the islands uniform, the variation coefficient of the Feret horizontal diameter of the island portion in the toner particles of the present invention is 30%. The following is preferred, and more preferably 25
%, Particularly preferably 20% or less. The coefficient of variation of the Feret horizontal diameter of the island portion in the toner particles of the present invention is:
It is obtained by the following equation.

Coefficient of variation of Feret horizontal diameter = {S2 / K2}
× 100 (%) In the formula, S2 represents the standard deviation of the horizontal Feret diameter of 100 islands, and K2 represents the average value of the horizontal Feret diameter.

Here, the coefficient of variation of the Feret horizontal diameter of the island portion in the toner particles refers to the variation of the average value of the Feret horizontal diameter,
That is, it indicates the variation in the size of each island of the crystalline material.

The toner particles of the present invention preferably have a sea-island structure, and the above-mentioned sea-island structure is represented by a cross-sectional photograph of the toner particles taken with a transmission electron microscope.
It can be confirmed that the toner particles have regions having different luminances. That is, according to the transmission electron microscope, the toner particles of the present invention have, in the continuous phase (binder resin phase), granular islands (crystalline substance phase and colorant phase) having different luminances in the continuous phase. Is confirmed. Further, based on the results obtained from the observation results of the electron microscope, factors specifying the sea-island structure in the toner particles, such as the number of islands in one toner particle, the shape factor of the island, and the horizontal diameter of the ferret of the island, are obtained as numerical values. It is something that can be done.

The luminance in a transmission electron micrograph is defined as the difference in the electron beam transmittance generated due to the difference in the crystal state of each element constituting the toner particles, that is, the binder resin, the colorant, and the crystalline substance. This is caused by visualization. Generally, the colorant is photographed at a lower luminance because the transmittance of the electron beam is lower than that of the binder resin, and the crystalline substance is photographed at a higher luminance than the binder resin.

In electron micrographs, low luminance means 0 when a luminance signal of a pixel is divided into 256 gradations.
~ 99 gradations, medium brightness is 80 ~ 160
In the range of gradations and high luminance are those in the range of 127 to 255 gradations, but in the present invention, if they are relative, that is, if the above-mentioned components of the toner particles can be distinguished by photographs, respectively. It is not necessarily limited to the above range.

As described above, according to the present invention, by identifying each component in the toner particles based on the luminance, it is possible to visually determine and identify the sea as the sea and the island as the island by electron micrograph. The brightness information is converted into visually identifiable image information by an image analysis device installed in the electron microscope device.

The Voronoi polygon (also referred to as Voronoi polyhedron), which is one type of parameters relating to the shape of the toner particles of the present invention, and the area of the Voronoi polygon will be described.

The area of the Voronoi polygon used in the present invention indicates the occupation state of the island in the toner particles. A Voronoi polygon or Voronoi polyhedron is
For example, as described in the Encyclopedia of Physical and Chemical Sciences of Iwanami, when a large number of points are dispersed in space or on a plane, by creating a perpendicular bisector and a perpendicular bisector of adjacent points The whole space is divided into polyhedra or the whole plane is divided into polygons.Polyhedrons formed in this way are called Voronoi polyhedra, polygons are called Voronoi polygons, and such division of space and plane is called Voronoi division . FIG. 1 is a schematic diagram illustrating an example of toner particles according to the present invention divided by a Voronoi polygon.

As described above, according to the present invention, as a scale representing the ratio of islands in toner particles, the occupation state of islands in the sea-island structure of toner particles is determined by the area of a Voronoi polygon obtained by Voronoi division. It is shown. That is, the present invention focuses on the centers of gravity of the islands present in the toner particles, forms polygons by vertical bisectors formed by connecting the centers of gravity of adjacent islands, and transmits the areas of these polygons through the transmission area. The calculation is performed by an image analyzer installed in the electron microscope apparatus based on the result of the photograph taken by the scanning electron microscope.

A Voronoi polygon having a large area is as follows.
This indicates that the distance between the centers of gravity of adjacent islands is distant, that is, the island is occupied sparsely in the particle. Also, a small Voronoi polygon area indicates that the distance between the centers of gravity of adjacent islands is short and close, that is, that the occupation state of islands in particles is dense. It is. In the present invention, the Voronoi polygon of the island portion in the toner particles is measured for 1000 toners, and the average value is calculated.

The Voronoi polygon is mathematically generally defined by the following equation.

<Area of Voronoi polygon> Two-dimensional space R
N independent points P in a two- or three-dimensional space R3
(I) Voronoi polygon V (i) for (1 ≦ i ≦ N)
V (i) = {X || XP (i) | <| XP (j) | for all i to j} In the formula, X and P represent position vectors, and | | Indicates the distance in Euclidean space.

Assuming that V (i) thus defined forms a Voronoi polygon in R2 and a Voronoi polyhedron in R3, when V (i) and V (j) are adjacent to each other, a boundary of the Voronoi polygon is formed. Is defined as a part of a perpendicular bisector of a line connecting the points P (i) and P (j). The Euclidean space is as defined and described in the Dictionary of Mathematical Sciences and the like.

Further, the center of gravity of the toner particles and the center of gravity of each island in the toner particles of the present invention are obtained by the moment of the image, and are automatically calculated by the image analyzer installed in the transmission electron microscope. You. Here, the barycentric coordinates of the toner particles are obtained by multiplying a luminance value of a small area at an arbitrary point of the toner particle by a coordinate value of the arbitrary point. Then, for all coordinates existing in the entire toner particle, the product of the luminance and the coordinate value is obtained, and the sum of the products is calculated as the luminance of the toner particle (the sum of the luminance values at each coordinate point obtained as described above). It is required by dividing. Similarly, the center of gravity of the island is calculated by calculating the luminance at an arbitrary coordinate point in the island. As described above, both the barycentric coordinates of the toner particles of the present invention and the barycentric coordinates of each island present in the toner particles are calculated based on the brightness at each arbitrary point, that is, from the brightness of the image.

In the present invention, the average value of the area of the Voronoi polygon formed by the perpendicular bisector between the centers of gravity of the adjacent islands in the toner particles is 20,000 nm ^{2 to} 120,000.
0 nm ² and the coefficient of variation of the average value of the area is 2
It is less than 5%. In the present invention, the coefficient of variation of the area of the Voronoi polygon is calculated by the following equation.

Coefficient of variation of Voronoi polygon area = ｛S4
/ K4｝ × 100 (%) In the formula, S4 indicates the standard deviation of the area of the Voronoi polygon of the island portion existing in the toner particles, and K4 indicates the average value of the area of the Voronoi polygon.

[0135] Further, the average value of the area of the Voronoi polygons adjacent each other islands in the toner particles of the present invention is more preferably 40,000nm ² ~100,000nm ^2, and its variation coefficient of 20 % Or less.

The variation coefficient of the average value of the area of the Voronoi polygon formed by the adjacent islands in the toner particles of the present invention is the one that specifies the variation in the area of the Voronoi polygon,
That is, the variation of the occupation state of the island portion in the toner particles is specified, and the variation coefficient of the average value of the area of the Voronoi polygon may be in a range of 25% or less, and preferably 20% or less. When the coefficient of variation is 0%,
That is, the state in which the average value of the Voronoi polygon area does not vary, in other words, the state in which the occupation state of the islands in the toner particles does not vary at all, that is, the necessity of the same occupation state of the islands in all the toner particles is required. There is nothing at all.

Further, in the present invention, the area of the Voronoi polygon formed by the islands located within a specific range from the center of gravity of the toner particles is larger than the area of the Voronoi polygon formed by the islands located outside the range. It is characterized by being small. That is, in the present invention, the average value of the area of the Voronoi polygon formed by the islands existing outside the radius of 1000 nm from the center of gravity of the toner particles is 1
This is larger than the average value of the area of the Voronoi polygons formed by the islands within 000 nm, which means that in the toner particles, the dispersed state of the islands is sparse at a certain distance from the center of gravity of the toner particles. It means that it is. By satisfying this condition, in the toner of the present invention, the effect achieved by the present invention by appropriately dispersing the islands in the toner particles can be obtained more effectively.

In the present invention, the islands are appropriately dispersed, the islands are appropriately spaced from each other, the islands are not unevenly distributed in the toner particles, and the colorant is effectively added to the toner particles. From, the area of the Voronoi polygon is 160,000
It is preferable that 5 to 30 islands having a nm ² or more exist in one toner particle.

(Molecular Weight Distribution of Resin Particles and Toner) In the toner of the present invention, the peak or shoulder of the molecular weight distribution is 10%.
0.00-1,000,000, and 1,000-5
It is preferable that the peak is present at a molecular weight distribution of 100,000 to 1,000,000.
00, 25,000-150,000 and 1,000-
Preferably it is present at 50,000.

The molecular weight of the resin particles is from 100,000 to
A resin containing at least a high molecular weight component having a peak or shoulder in a region of 1,000,000 and a low molecular weight component having a peak or shoulder in a region of 1,000 to less than 50,000 is preferable, and more preferably a resin. Is
It is preferable to use an intermediate molecular weight resin having a peak or shoulder at a portion of 15,000 to 100,000.

The above-mentioned method for measuring the molecular weight of a toner or a resin is based on a method using GP (tetrahydrofuran) as a solvent.
Measurement by C (gel permeation chromatography) is good. That is, 1.0 ml of THF is added to 0.5 to 5 mg, more specifically, 1 mg of a measurement sample, and the mixture is stirred at room temperature using a magnetic stirrer or the like to be sufficiently dissolved. Then, pore size 0.45
After treatment with a 0.50 μm membrane filter,
Inject into GPC. GPC measurement conditions are as follows: stabilize the column at 40 ° C., flow THF at a flow rate of 1.0 ml per minute, and inject about 100 μl of a 1 mg / ml concentration sample for measurement. The column is preferably used in combination with a commercially available polystyrene gel column. For example, Shodex GPC KF-801, 80 manufactured by Showa Denko KK
2, 803, 804, 805, 806, 807 and TSKgel G1000H, G200 manufactured by Tosoh Corporation
0H, G3000H, G4000H, G5000H, G
6000H, G7000H, TSK guard co
and the like. As the detector, a refractive index detector (IR detector) or U
Preferably, a V detector is used. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve created using monodispersed polystyrene standard particles. It is preferable to use about 10 polystyrenes for preparing a calibration curve.

The developer used in the present invention will be described. The toner of the present invention may be used as a one-component developer or a two-component developer, but is particularly preferably used as a non-magnetic one-component developer.

When the toner of the present invention contains a fluorine atom as the component (a), X is used to sufficiently bring out the effects of the present invention.
In the measurement by line photoelectron spectroscopy (referred to as ESCA or XPS), a peak exists at 689.0 to 692.0 eV, and the ratio of the number of fluorine atoms to the number of carbon atoms calculated from the peak intensity is 0.001 to 0.001. It is preferably 0.04. Particularly preferably, 690.5 to 6
A peak exists at 91.0 eV, and the ratio of the number of fluorine atoms to the number of carbon atoms calculated from the peak intensity is 0.0
01 to 0.002.

The toner of the present invention exhibits a high fixing property and contains a crystalline compound in order to avoid the offset phenomenon described in JP-A-8-328295. One or more endothermic peaks in the differential thermal analysis due to the compound exist at 60 to 120 ° C,
The heat absorption is preferably 4 J to 30 J / g.

The metal oxide particles according to the present invention will be described. Metal oxide particles used in the present invention, silica,
Alumina, titanium oxide, magnetite, strontium titanate, barium titanate, etc., but silica,
Titanium particles are preferably used.

The silica used in the present invention is generally produced by a wet method or a dry method. In particular, it is referred to as a so-called fumed silica produced by a dry method (vapor phase oxidation of a silicon halide compound). Are preferred in terms of fluidity. This is manufactured by a conventionally known technique. For example, it utilizes the thermal decomposition oxidation reaction of silicon tetrachloride gas in an oxyhydrogen flame, and the basic reaction formula is as follows.

SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl In this production process, another metal halide such as aluminum chloride or titanium chloride is used together with a silicon halide to produce a composite fine powder of silica and another metal oxide. It is also possible to obtain a body, and the present invention includes those using them.

<Small Diameter Silica to be Used> (a) Silica having a number average particle diameter of 0.005 to 0.015 μm is added to toner 100 (without adding external additives).
It is preferable to add 0.1 to 0.8 parts by mass with respect to parts by mass. Commercially available silica fine powder includes, for example, those commercially available under the following trade names. For example, AER
OSIL (manufactured by Nippon Aerosil Co., Ltd.) 130, 200, 20
0V, 200CF, 200FAD, 300, 300C
F, 380; Ca-O-Sil (manufactured by CABOT) M-
5, MS-7D, MS-75D, H-5, HS-5, E
H-5; Wacker HDK N20 (WACKER
-CHFMIEGMBH) S13, V15, N2
0, T30, T40 and the like.

The following are examples of the silica subjected to the hydrophobic treatment. HDK H2 made by Clariant
000, 2000/4, 3004, 2050EP, HV
K21 and R972 and R974 manufactured by Nippon Aerosil Co., Ltd.
RX200, RY200, R202, R805, R81
There are 2 etc.

<Large-diameter silica to be used> (b) Number average particle diameter is 0.020 μm to 0.080 μm
m of silica added to toner 10 (without adding external additives)
It is preferable to add 0.2 to 1.2 parts by mass with respect to 0 parts by mass. More preferably, it is 0.3 to 0.8 parts by mass.

Examples of commercially available silica fine powder include those commercially available under the following trade names, for example. AERS
IL (manufactured by Nippon Aerosil Co., Ltd.) OX50, AEROSIL
50, TT600, MOX80, MOX170 and the like.

Examples of the silica subjected to the hydrophobic treatment include the following. TS630 (Cabot); NA-50H (Kao); RY-50, NY-
50, NAX-50, RX-50, RM-50 (all manufactured by Nippon Aerosil Co., Ltd.).

<Titanium Crystalline System> The titanium oxide fine particles used in the present invention include those manufactured by a sulfuric acid method and a chlorine method, and include rutile type, anatase type and amorphous type.

Rutile, anatase, mixed crystals of rutile and anatase, amorphous and mixed types thereof can all be used. However, from the viewpoint of securing fluidity and reducing the environmental dependence of charging, rutile-type titanium oxide and anatase can be used. Titanium oxide having a mass ratio of 2:98 to 45:55 with titanium oxide is preferably used. Further, it is preferable that the particle surface of the rutile-containing / anatase mixed titanium oxide is coated with a layer containing one or more of aluminum, silicon, titanium, zirconium and tin. That is, it is preferable that the surface of the particles before the treatment with the silane coupling agent is coated with a layer containing the predetermined element.

The reason why the layer is coated before the silane coupling agent treatment is performed is to adjust the charging property and the resistance. The treatment amount of the element is preferably 3 to 20% by mass. 3
If the amount is less than 20% by mass, it is difficult to obtain the effect of adjusting the charge.
If it exceeds 0% by mass, coalescence of the particles occurs, which is not preferable.

<Small Diameter Titanium Oxide Used> (c) The number of added titanium oxide particles having a number average particle diameter of 0.015 to 0.070 μm is the toner 10 (without adding external additives).
It is preferable to add 0.1 to 1.0 part by mass to 0 part by mass. More preferably, it is 0.2 to 0.8 parts by mass.

The following are specific examples of the titanium oxide fine particles. P-25 (made by Degussa); IT-
S, IT-PA, IT-PB (all manufactured by Idemitsu Kosan Co., Ltd.); R-820, R-830, R-680, CR-5
0, CR-60, A-100, A-220 (all manufactured by Ishihara Sangyo Co., Ltd.); MT-100SA, MT-150W, M
T-500B, MT-600B (both manufactured by Teika)
etc. Examples of the titanium oxide fine particles particularly subjected to the hydrophobic treatment include the following.

STT-30A, STT-30AS, ST
T-30S (all manufactured by Titanium Industry Co., Ltd.); T-805
(Manufactured by Nippon Aerosil Co., Ltd.); TTO-51 (manufactured by Ishihara Sangyo); TAF-1500S (manufactured by Fuji Titanium Co., Ltd.); M
T-100S and MT-100T (both manufactured by Teika).

<Large Diameter Titanium Oxide Used> d) The number of added parts of titanium oxide having a number average particle diameter of 0.08 to 0.2 μm is 0.2 to 100 parts by mass of the toner (without adding external additives). It is preferable to add 1.2 parts by mass.
More preferably, it is 0.3 to 1.0 part by mass.

Examples of commercially available titanium oxide particles include, for example, those commercially available under the following trade names. TTO
-51 (A) and TTO-51 (B) (all manufactured by Ishihara Sangyo); TAF-620 (manufactured by Fuji Titanium Industry).

Examples of the titanium oxide fine particles particularly subjected to the hydrophobic treatment include the following. STT-6
0J (manufactured by Titanium Industry Co., Ltd.); JA-1, JA-3, JA-
4, JA-5 (all manufactured by Teica); TAF-52
0, TAF-520AS, TAF-520K (all manufactured by Fuji Titanium Industry Co., Ltd.) and the like.

(Preferably Used Coupling Agent) The hydrophilic fine particles can be obtained by treating with a silane coupling agent such as methyltrimethoxysilane, methyltriethoxysilane or octyltrimethoxysilane.

Specific coupling agents are shown below. _{CH 3 (CH 2) 2 SiCl} 3 CH 3 (CH 2) 5 SiCl 3 CH 3 (CH 2) 7 SiCl 3 CH 3 (CH 2) 9 SiCl 3 CH 3 (CH 2) 9 Si (OCH 3) 3 CH _{3 (CH 2) 9 Si (} CH 3) Cl 2 CH 3 (CH 2) 2 Si (OCH 3) 3 CH 3 (CH 2) 2 Si (CH 3) (OCH 3) 2 CH 3 (CH 2) 5 _{Si (OCH 3) 3 CH 3} (CH 2) 5 CONH (CH 2) 2 Si (OC 2 H 5) 3 CH 3 (CH 2) 4 COO (CH 2) 2 Si (OCH 3) 3 CH 3 (CH _{2) 9 Si (OCH 3)} 3 CH 3 (CH 2) 9 Si (CH 3) (OCH 3) 2 CH 3 (CH 2) 7 SO 2 NH (CH 2) 3 Si (OC 2 H 5)
_{3 CH 3 (CH 2) 8} (CH 2) 2 Si (OCH 3) 3 CF 3 (CH 2) 2 SiCl 3 CF 3 (CF 2) 5 SiCl 3 CF 3 (CF 2) 5 (CH 2) 2 SiCl _{3 CF 3 (CF 2) 7} (CH 2) 2 SiCl 3 CF 3 (CF 2) 7 CH 2 CH 2 Si (OCH 3) 3 CF 3 (CF 2) 7 (CH 2) 2 Si (CH 3) Cl _{2 CF 3 (CH 2) 2} Si (OCH 3) 3 CF 3 (CH 2) 2 Si (CH 3) (OCH 3) 2 CF 3 (CF 2) 3 (CH 2) 2 Si (OCH 3) 3 CF _{3 (CF 2) 5 CONH (} CH 2) 2 Si (OC 2 H 5) 3 CF 3 (CF 2) 4 COO (CH 2) 2 Si (OCH 3) 3 CF 3 (CF 2) 7 (CH 2) _{2 Si (OCH 3) 3 CF} 3 (CF 2) 7 (CH 2) 2 Si (CH 3) (OCH 3) 2 CF 3 (CF 2) 7 SO 2 NH (CH 2 ) ₃ Si (OC ₂ H ₅ )
₃ CF ₃ (CF ₂ ) ₈ (CH ₂ ) ₂ Si (OCH ₃ ) _{3 and the} like. Also, it can be obtained by polysiloxane treatment.

The treatment amount is 10 to 100% by mass, preferably 20 to 70% by mass, based on 100% by mass of silica or titanium oxide. When the treatment amount is 10% by mass or less, not only low hydrophobicity can be obtained, but also strong fixation occurs during drying, resulting in poor dispersion. When the treatment amount is 100% by mass or more, the decrease in specific surface area is reduced. May be undesirably large.

<Lubricant Used in Conjunction with External Additive> Examples of the lubricant that can be used as the external additive include metal salts of higher fatty acids. Specific examples of such metal salts of higher fatty acids include metal stearate salts such as zinc stearate, aluminum stearate, copper stearate, magnesium stearate, and calcium stearate; zinc oleate, manganese oleate, iron oleate, and olein. Metal oleate such as copper phosphate and magnesium oleate; metal palmitate such as zinc palmitate, copper palmitate, magnesium palmitate and calcium palmitate; metal linoleate such as zinc linoleate and calcium linoleate; ricinol And metal salts of ricinoleic acid such as zinc acid and calcium ricinoleate.

The amount of the external additive is preferably about 0.1 to 5% by mass based on the toner.

<Step of Adding External Additive> This step is a step of adding an external additive to the dried toner particles.

Examples of a device used for adding an external additive include a turbulent mixer, a Henschel mixer,
Various known mixing devices such as a Nauta mixer and a V-type mixer can be used.

In the present invention, the surface of the treated layer treated with the silane coupling agent may be further coated with a coupling agent and / or silicone oil.
That is, after treating the silane coupling agent in an aqueous medium, the silane coupling agent or an organosilicon compound such as silicone oil can be treated in the gas phase to improve the hydrophobicity and adjust the charge amount.

As the silane coupling agent that can be used in this case, fluorosilane, aminosilane, polydimethylsiloxane, methylhydrogenpolysiloxane and the like can be used in addition to those described above.

When the treatment is carried out in the gas phase, the treatment amount is 1 to 20% by mass, especially 3 to 1% by mass, based on 100% by mass of the obtained fine powder.
Preferably, the treatment is performed at 5% by mass. If the treatment amount is less than 1% by mass, the effect cannot be obtained, and if it exceeds 20% by mass, the specific surface area is undesirably low.

The charge control agent used in the toner of the present invention will be described. Examples of the charge control agent include a nigrosine dye, a metal salt of naphthenic acid or a higher fatty acid, an alkoxylated amine, a quaternary ammonium salt compound, an azo metal complex, a metal salt of salicylic acid, and a metal complex thereof.

As the fixing improver used in the present invention, a crystalline compound having an ester group is preferably used. Specific examples include higher fatty acid esters, natural waxes such as carnauba wax and rice wax, and crystalline polyesters.

Among the compounds having an ester group, particularly preferred are ester compounds represented by the following general formula.

In the general formula R _1- (OCO-R ₂ ) _n , n represents an integer of 1 to 4, preferably 2 to 4, more preferably 3 to 4, and particularly preferably 4.

R ₁ and R ₂ each represent a hydrocarbon group which may have a substituent. R ₁ : carbon number = 1 to 40, preferably 1 to 20, more preferably 2 to 5 R ₂ : carbon number = 1 to 40, preferably 13 to 29, more preferably 12 to 25 or less, Specific examples of the crystalline compound having such an ester group will be shown, but the present invention is not limited thereto.

[0177]

Embedded image

[0178]

Embedded image

The crystalline compound having an ester group according to the present invention is contained in resin particles and has a function of imparting good fixability (adhesion to an image support) to a toner obtained by fusing the resin particles. Having.

The melting point of the crystalline compound is 60 to
It is preferably in the range of 110 ° C, more preferably in the range of 70 to 90 ° C.

The image forming method of the present invention will be described.
The image forming method of the present invention and the image forming apparatus shown in FIG. 2 used in the image forming method will be described.

FIG. 2 is a schematic diagram showing an embodiment of the image forming apparatus used in the present invention. Reference numeral 400 denotes a photoconductor, which is a typical example of the electrostatic latent image forming body in the present invention. An organic optical semiconductor (OPC), which is a photoconductor layer, is formed on the outer peripheral surface of an aluminum drum base, and rotates at a predetermined speed in the direction of the arrow. The outer diameter of the photoreceptor 400 is 15 to
120 mm is often used.

In FIG. 2, the semiconductor laser light source 11 is read based on information read by a document reading device (not shown).
Exposure light is emitted from 6. This is the polygon mirror 22
0, the image is distributed in the direction perpendicular to the plane of FIG. 2 and is irradiated onto the photoreceptor surface via an fθ lens 300 for correcting image distortion to form an electrostatic latent image. The photoreceptor is uniformly charged in advance by the charger 500 and rotates clockwise in accordance with the timing of image exposure.

The electrostatic latent image on the surface of the photoreceptor is developed by the developing device 600, and the formed developed image (image) is transferred to the image carrier 800 which has been conveyed at a proper timing.
Transcribed by the action of 00. Further, the photoconductor 400 and the image carrier 800 are separated by a separator (separation pole) 900, and the toner image is transferred and carried on the image carrier 800, guided to the fixing device 115, and fixed.

The untransferred toner remaining on the photoreceptor surface is
After being cleaned by a cleaning device 250 of a cleaning blade type, the residual charge is removed by a pre-charging exposure (PCL) 260, and is uniformly charged again by the charger 500 for the next image formation. The cleaning blade 270 has a thickness of 1
It is made of a rubber-like elastic body of about 30 mm, and urethane rubber is most often used.

The method for recycling the toner is not particularly limited. For example, the toner collected by the cleaning unit is transported by a transport conveyor or a transport screw to a replenishment toner hopper, a developing device, or a replenishment toner. A method of mixing and supplying the mixture to the developing device depending on the chamber can be given. Preferably, a method of directly returning the toner to the developing device or a method of mixing the replenishment toner and the recycled toner in the intermediate chamber and supplying the mixed toner can be used.

Hereinafter, an image forming apparatus used in the image forming method of the present invention will be described with reference to FIG. FIG. 3 is a schematic sectional view of a developing device for explaining a developing method of the present invention and a sectional view of a main part thereof. The developing device used in the image forming method of the present invention is not limited to the one shown in FIG.

FIG. 3A is a schematic sectional view showing the structure near the developing device according to the embodiment, and FIG. 3B is a sectional view of a main part thereof.
As shown in the figure, the developing device 3 is located at a position close to the peripheral surface of the photosensitive drum 1 such that the developing sleeve (developer carrier) 214 faces the photosensitive drum (electrostatic latent image carrier) 1. It is provided in. A positioning member (a 0.1 mm-thick polyester film) 216 is interposed between the developing sleeve 214 and the photosensitive drum 1, whereby a gap (a gap) between the developing sleeve 214 and the photosensitive drum 1 is formed. ) The distance Ds is set to a predetermined value.

A non-magnetic one-component toner (developer, for example, a polyester resin having an average particle size of 8.5 μm) is stored in the hopper 212 of the developing device 3. Inside the developing sleeve 2
It reaches 14. The toner that has reached the developing sleeve 214 is charged to a predetermined polarity by friction with a regulating member (eg, a SUS (stainless steel) plate having a thickness of 0.1 mm) 215 and is carried in a thin layer on the peripheral surface of the developing sleeve 214. You. The thickness of this thin layer is determined by the material and pressing force of the regulating member 215, but in this example, the peripheral speed of the photosensitive drum 1 is set to 100 mm /
sec, the peripheral speed of the developing sleeve 214 is set to 200 mm / s
ec, by setting the pressing force of the regulating member 215 against the developing sleeve 214 to 10 to 100 N / m,
Layer (thickness of about 1.5 toner particles). The process in which the toner is charged to a predetermined polarity by frictional charging with the regulating member 215 and is carried in a thin layer on the peripheral surface of the developing sleeve 214 is described in, for example, JP-B-63-163.
Since it is publicly known as described in US Pat. No. 15,580, the description is omitted.

The developing sleeve 214 is formed in a cylindrical shape (for example, 17 mm in diameter) using a flexible material having conductivity (for example, polyamide resin having a thickness of 1 mm).
Inside the developing sleeve 214, the drive roller 2 having a diameter slightly smaller than the developing sleeve 214 (for example, 16 mm in diameter)
When the driving roller 213 rotates in the direction of the arrow, the developing sleeve 214 is driven by the frictional force between the outer peripheral surface of the driving roller 213 and the inner peripheral surface of the developing sleeve 214 to rotate in the same direction. It is configured as follows. As described above, since the developing sleeve 214 is flexible and has a slightly larger diameter than the driving roller 213, there is some slack. This slack is regulated by the regulating member 215 and a guide belt (not shown) so as to occur on the side facing the photosensitive drum 1. Therefore, a part of the pressing force from the developing sleeve 214 is absorbed by the slack, and as a result, the developing sleeve 2
The pressing force applied from the developing sleeve 214 to the positioning member 216 inserted between the photoconductor drum 1 and the photoconductor drum 1 is relatively low.

The toner carried in a thin layer on the peripheral surface of the developing sleeve 214 is conveyed with the rotation of the developing sleeve 214 and reaches the developing area Da. The development area Da is defined by the action of an electric field formed by the developing bias voltage Vb and the alternating voltage applied from the developing bias power supply device by the toner on the peripheral surface of the developing sleeve 214.
Is an area where the electrostatic latent image on the peripheral surface of the photosensitive drum 1 is developed by flying from the peripheral surface of the photosensitive drum 1. This area is also an area within the nip width Da between the developing sleeve 214 and the photosensitive drum 1. The developing bias power supply device includes a DC voltage power supply that outputs a set value of the developing bias voltage Vb (eg, about −500 V) and an alternating electric field (eg, Vpp 2.0).
(kV, frequency 2 kHz).

Regarding the process of developing the electrostatic latent image on the photoreceptor by converting the toner flying from the developing sleeve into a powder cloud due to the alternating electric field, for example, the basics and applications of electrophotographic technology (edited by the Electrophotographic Society, Corona As described on pages 158 to 170 of the company, the description is omitted. Vpp means a peak-to-peak voltage which is a difference between a peak and a valley of the amplitude of the alternating voltage waveform.

In the present embodiment, the photosensitive drum 1 is a photoconductive drum having a surface composed of a negatively charged organic photosensitive member and rotating at a constant speed in the direction of the arrow in the figure. The photosensitive drum 1 has a uniform potential (eg, -8) by a charging device (not shown).
After being charged to about 00V, it is exposed by an optical head such as a laser to attenuate the potential (eg, about -100V). That is, an electrostatic latent image is formed. When the electrostatic latent image reaches the development area Da, the toner that has been turned into a powder cloud as described above adheres to the potential attenuation portion,
Development takes place.

The positioning member 216 is in contact with the developing sleeve 214 so that its leading edge (lower end in the figure) 16a is located within the developing area Da and is parallel to the longitudinal direction of the developing area Da. The developing sleeve 214 is inserted at a position on the upstream side in the rotation direction (the position on the upper half side in the drawing) between the photosensitive drum 1 and the developing sleeve 214. As a result, the gap distance Ds between the developing sleeve 214 and the photosensitive drum 1 is set to a predetermined value, and since the leading edge 216a is provided along the longitudinal direction, the gap distance Ds is set over the entire image width. It is set to an appropriate value. As described above, the positioning member 216 is formed of a polyester film having a thickness of 0.1 mm as described above, but is not limited to the polyester film.
The material may be selected in consideration of the balance with the frictional charging of the toner. For example, by using a charging series material having the opposite polarity to the charging polarity of the toner, the frictional charging by the regulating member 215 is assisted or promoted. You may comprise. In addition, the surface in contact with the developing sleeve 214 is formed of a conductive material as a two-layer structure, and by applying a voltage having the same polarity as the charging polarity of the toner, the toner is prevented from adhering and the charging of the toner is assisted. You may make it.

In this example, the positioning member 216 is
As shown, it is provided on the upstream side of the rotation of the developing sleeve 214 and the photosensitive drum 1 and shields the upstream part in the developing area Da, but is provided on the downstream side and is provided on the downstream side in the developing area Da. May be shielded. When provided on the upstream side as in this example, since the positioning member 216 is provided along the rotation direction, the resistance received from the developing sleeve 214 and the photosensitive drum 1 is reduced, and a problem occurs in toner flying. There is an effect that it is difficult. Even when at least one of the developing sleeve 214 and the photosensitive drum 1 has flexibility or elasticity, the gap distance Ds
Has an effect that can be set to an appropriate value.

Next, the leading edge 21 of the positioning member 216
The relationship between the position 6a, the gap distance Ds between the developing sleeve 214 and the photosensitive drum 1, and the toner adhesion amount will be described. The flying of the toner from the surface of the developing sleeve 214 and the formation of the powder cloud are mainly determined by the gap distance Ds, the width Da of the developing area in the rotation direction, and the developing bias voltage Vb. In the case of forming an alternating electric field,
The amplitude difference voltage Vp-p of the applied voltage waveform also contributes. When a flying type developing device is configured, it is relatively easy to improve the accuracy on the power supply side, but it is difficult to stably secure the gap distance Ds. For this reason, in this example,
The positioning member 216 is used.

The gap distance Ds can be easily set to an appropriate value by the positioning member 216 as described above. However, the presence of the positioning member 216 blocks a part of the developing area (the upper part in the illustrated example). Would.
For this reason, the amount of toner adhered on the photosensitive drum 1 is reduced, which causes a problem that the development density is reduced. In order to obtain a sufficient print image density, it is sufficient that the toner adhering amount is 0.7 mg / cm ² or more, and the developing nip width D is 1.5 mm or more.
By ensuring a, a sufficient amount of toner adhered can be obtained.

For this reason, it is necessary to set the position of the leading edge 216a of the positioning member 216 within a range where the developing nip width Da is 1.5 mm or more.

The above example can be variously modified. For example, an amplitude voltage difference Vp for forming an alternating electric field
p is about 100 to 3000 V, and its frequency is 1
A triangular wave or a rectangular wave can be used as the waveform at about 00 to 10 kHz. Further, the thickness of the positioning member 216 may be about 0.01 to 0.5 mm, and may be used in combination with the above-described alternating electric field. Magnetic toner can be used instead of non-magnetic toner. Further, a developing roller may be used instead of the flexible developing sleeve, and the photoconductor may be configured to have elasticity. Further, by detaching the positioning member 216 in the non-image printing area, it can be used as a simultaneous developing and cleaning device.

Next, an example of a perspective view of a toner recycling member will be described with reference to FIG. In this method, the recycled toner is directly returned to the developing device.

The untransferred toner collected by the cleaning blade 130 is collected in a toner recycling pipe 140 by a conveying screw in the cleaning device 110,
Further, the developing device 6
It is returned to 00 and is used again as a developer.

FIG. 4 is also a perspective view of a process cartridge detachable from the image forming apparatus of the present invention. This FIG.
Although the photoreceptor unit and the developer unit are separated in order to make the perspective structure easy to understand, they can be removably mounted as an integrated unit in the image forming apparatus. In this case, the photoconductor 400, the developing device 600,
The cleaning device 110 and the recycling member are integrated to form a process cartridge.

[0203] The image forming apparatus may be provided with a photosensitive drum and a process cartridge including at least one of a charger, a developing device, a cleaning device, and a recycling member.

Next, the transfer paper is typically plain paper, but is not particularly limited as long as it can transfer an unfixed image after development, and of course includes a PET base for OHP.

Further, the cleaning blade 130 uses a rubber-like elastic body having a thickness of about 1 to 30 mm, and urethane rubber is most often used as a material. Since this is used by being pressed against the photoconductor, it is easy to conduct heat. In the present invention, it is desirable to provide a release mechanism and keep the photoconductor away from the photoconductor when the image forming operation is not performed.

The present invention can also be used in an image forming apparatus by electrophotography, particularly in an apparatus for forming an electrostatic latent image on a photoreceptor by a modulated beam modulated with digital image data from a computer or the like.

For example, FIG. 5 is a schematic configuration diagram showing an example of a color electrophotographic image forming apparatus applied to the toner of the present invention.

In the main body of the color electrophotographic image forming apparatus, first, second, third and fourth image forming sections Pa, Pb, Pc are provided.
And Pd are installed in parallel. Each image forming unit has the same configuration, and forms visible images (toner images) of different colors.

The image forming units Pa, Pb, Pc and Pd are:
Each has a dedicated electrostatic latent image carrier (electrophotographic photosensitive drum) 1a, 1b, 1c and 1d. Electrophotographic photoreceptor drums (may be abbreviated as photoreceptor drums) 1a, 1a formed by image forming portions Pa, Pb, Pc and Pd
The images on b, 1c and 1d are transferred onto a recording material (transfer material, image support) carried and conveyed on a recording material carrier 18 moving adjacent to each image forming section. Further, the image on the recording material is fixed by heating and pressing in a fixing unit (fixing device) 10, and the recording material is discharged to a tray 61.

Next, the latent image forming section in each image forming section will be described. Photoconductor drums 1a, 1b, 1c, 1d
Around the discharge lamps 21a, 21b, 21
c, 21d, drum chargers 2a, 2b, 2c, 2d, laser beam exposure device 17 as image exposure means, and potential sensors 22a, 22b, 22c, 22d.
The photosensitive drums 1a, 1b, 1c, and 1d whose charges have been removed by the charge removing exposure lamps 21a, 21b, 21c, and 21d are uniformly charged by drum chargers 2a, 2b, 2c, and 2d. , An electrostatic latent image is formed on the photosensitive drums 1a, 1b, 1c, and 1d by color separation according to the image signal. In the image forming apparatus of the present invention, in addition to the laser beam exposure device 17 described above, a plurality of light levels other than OFF in a basic image unit (pixel) such as an LED array exposure device are used as image exposure means. A well-known multi-value exposure means capable of irradiating the light can be suitably used.

[0211] The electrostatic latent image on the photosensitive drum is developed by a developing means to become a visible image. That is, the developing means
Developing units 3a, 3b, and 3 filled with a predetermined amount of cyan, magenta, yellow, and black developers, respectively.
c, 3d, and the photosensitive drums 1a, 1b,
The electrostatic latent images formed on 1c and 1d are developed into visible images (toner images).

Next, the transfer section will be described. The recording material held in the recording material cassette 60 is fed to the recording material carrier 18 via a registration roller.

When the recording material carrier 18 starts rotating,
The recording material is conveyed from the registration roller onto the recording material carrier 18. At this time, the image writing signal is turned on, and the first electrophotographic photosensitive drum 1a is
An image is formed thereon.

A transfer charger 4a and a transfer pressing member 41a are provided below the first electrophotographic photosensitive drum 1a, and apply a uniform pressing force toward the photosensitive drum by the transfer pressing member 41a. The transfer charger 4a applies an electric field to transfer the toner image on the photosensitive drum 1a onto a recording material. At this time, the recording material is the recording material carrier 1
8, the recording material is conveyed to the second image forming portion Pb, and the next transfer is performed. Hereinafter, the third and fourth image forming units Pc, P
The recording material to which the toner image formed by d is transferred is
The charge is removed by the separation charger (separation pole) 9, separated from the recording material carrier 18 by the attenuation of the electrostatic attraction force, and conveyed to the fixing unit (fixing unit) 10.

The fixing section 10 includes a heat roller 71, a pressure roller 72, heat-resistant cleaning members 73 and 74 for cleaning the rollers 71 and 72, and rollers 71 and 72, respectively.
75 and 76, an oil application roller 77 for applying a release agent oil such as dimethyl silicone to the heating roller 71, and an oil reservoir 7 for supplying the oil.
8, a thermistor 79 for controlling the fixing temperature.

After the transfer, the photosensitive drums la, lb, lc,
The toner and the like remaining on the photoconductor cleaning unit 5
a, 5b, 5c and 5d to prepare for the next latent image formation. Further, the toner and the like remaining on the image support 8 are removed by the belt static eliminator 12 to remove the electrostatic attraction force, and then removed by the cleaning device 62 provided with a nonwoven fabric in this example. As the cleaning device 62, a rotating fur brush, a blade, a device using these in combination, or the like is also used.

FIG. 6 is a cross-sectional view showing an example of a fixing device used in the image forming method using the toner of the present invention. The fixing device shown in FIG. And a roller 20. In FIG. 6, T is a toner image formed on transfer paper (image forming support).

The heating roller 12 has a heating roller coating layer 12a made of fluororesin or an elastic material formed on the surface of the core metal of the heating roller, and a heating member 1 made of a linear heater.
3 is included.

The core of the heating roller is made of metal,
Its inner diameter is 10 to 70 mm. The metal constituting the core metal of the heating roller is not particularly limited, for example, iron,
Examples thereof include metals such as aluminum and copper or alloys thereof.

The thickness of the core of the heating roller is 0.1 to 15 m.
m, which is determined in consideration of the balance between the demand for energy saving (thinning) and the strength (depending on the constituent materials). For example, the same strength as a 0.57 mm iron core,
In order to hold with a metal core made of aluminum, its thickness is preferably set to 0.8 mm.

Examples of the fluorine resin constituting the coating layer 12a of the heating roller include PTFE (polytetrafluoroethylene) and PFA (tetrafluoroethylene-perfluoroalkylvinyl ether copolymer).

From the viewpoints of securing the durability as a fixing device and preventing image stains, the thickness of the coating layer 12a of the heating roller made of a fluororesin is preferably from 10 to 500 μm, more preferably from 20 to 400 μm.

As the elastic body constituting the coating layer 12a of the heating roller, it is preferable to use silicone rubber and silicone sponge rubber having good heat resistance such as LTV, RTV and HTV. Heating roller coating layer 1
The Asker C hardness of the elastic body constituting 2a is preferably less than 80 °, more preferably less than 60 °.

Further, in order to obtain the effect of soft fixing (for example, the effect of improving color reproducibility by the toner layer at the smoothed interface), the coating layer 12a of the heating roller made of an elastic material is required.
Is preferably from 0.1 to 30 mm, more preferably from 0.1 to 20 mm.

As the heating member 13, a halogen heater can be suitably used. The pressure roller 20 has a coating layer 22 made of an elastic body formed on the surface of a metal core 21. The elastic body constituting the coating layer 22 is not particularly limited, and examples thereof include various soft rubbers such as urethane rubber and silicone rubber and sponge rubber, and the silicone rubber and the silicone sponge rubber exemplified as those constituting the coating layer 22. It is preferable to use

Elastic Asker C constituting the coating layer 22
The hardness is preferably less than 80 °, more preferably 70 °
And particularly preferably less than 60 °.

The thickness of the coating layer 22 is 0.1 to 30 m.
m is preferred, and more preferably 0.1 to 20 mm.

The material constituting the core metal 21 is not particularly limited, but examples thereof include metals such as aluminum, iron, and copper or alloys thereof.

The contact load (total load) between the heating roller 12 and the pressure roller 20 is usually 40 to 350 N.
Preferably 50 to 300 N, more preferably 50 to 2
50N. The contact load is defined in consideration of the strength of the heating roller 12 (thickness of the core of the heating roller). For example, in the case of a heating roller having a core of 0.3 mm iron, the contact load is set to 250 N or less. Is preferred.

Further, from the viewpoint of offset resistance and fixing property, the nip width is preferably 4 to 10 mm, and the surface pressure of the nip is 0.6 × 10 ⁵ Pa to 1.5 mm.
It is preferably × 10 ⁵ Pa. As an example of the fixing conditions by the fixing device shown in FIG. 6, the fixing temperature (the surface temperature of the heating roller 12) is preferably 150 to 210 ° C.
The fixing linear velocity is preferably from 80 to 640 mm / sec.

[0231]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these.

Example 1 << Production Example of Metal-Free Phthalocyanine Particles >> (Preparation of Metal-Free Phthalocyanine Particles 1) 128 parts by mass of o-phthalodinitrile and 2.4 parts by mass of lithium hydroxide were added to 400 parts by mass of diethylene glycol. The temperature was raised to 100 ° C. with stirring, and when it was confirmed that the inside of the system had turned green, 11.2 parts by mass of ferrocene was added.

Subsequently, the reaction temperature was raised to 160 ° C.
After stirring for 60 hours, the mixture was cooled to 60 ° C and methanol 400
Then, the product was filtered, washed with 400 parts by weight of methanol, reslurried in 5 liters of 1% hydrochloric acid for 1 hour, filtered, and washed with water until the filtrate became neutral.
The mixture was filtered to obtain 560 parts by mass of a metal-free phthalocyanine particle water wet paste having a solid content of 20% by mass.

The resulting metal-free phthalocyanine particles are referred to as metal-free phthalocyanine particles 1. (Preparation of metal-free phthalocyanine particles 2) In the preparation of metal-free phthalocyanine particles 1, diethylene glycol 4
The same treatment was conducted except that 00 parts by mass was replaced by 300 parts by mass of octanol and 11.2 parts by mass of ferrocene was replaced by 15.0 parts by mass of cyclohexyl ferrocene.
Mass% of metal-free phthalocyanine particle water wet paste 56
0 parts by weight were obtained.

The resulting metal-free phthalocyanine particles are referred to as metal-free phthalocyanine particles 2. (Preparation of Metal-Free Phthalocyanine Particles 3) In preparation of metal-free phthalocyanine particles 1, 2.4 parts by mass of lithium hydroxide was added to 4.0 parts by mass of sodium hydroxide, and ferrocene 1 was added.
The same reaction and treatment were carried out except that 1.2 parts by mass was changed to 14.6 parts by mass of n-butyl ferrocene, and a water-free paste 560 of metal-free phthalocyanine particles having a solid content of 22% by mass was used.
Parts by weight were obtained.

The obtained metal-free phthalocyanine particles are referred to as metal-free phthalocyanine particles 3. (Preparation of metal-free phthalocyanine particles 4) In the preparation of metal-free phthalocyanine particles 1, diethylene glycol 4
00 parts by mass to 400 parts by mass of ethylene glycol, 11.2 parts by mass of ferrocene to 13.7 parts by mass of acetylferrocene, 2.4 parts by mass of lithium hydroxide to potassium carbonate 1
When the reaction and treatment were carried out in the same manner except that the amount was changed to 2 parts by mass,
500 parts by mass of a wet paste containing metal-free phthalocyanine particles having a solid content of 18% by mass was obtained.

The obtained metal-free phthalocyanine particles are referred to as metal-free phthalocyanine particles 4. (Preparation of metal-free phthalocyanine particles 5) In preparation of metal-free phthalocyanine particles 1, o-phthalodinitrile 1
28 parts by mass of 4-methoxy-o-phthalodinitrile 15
When the same reaction and treatment were carried out except that the amount was changed to 8 parts by mass,
As a result, 533 parts by mass of a metal-free phthalocyanine particle water wet paste having a solid content of 27% by mass was obtained. The obtained metal-free phthalocyanine particles are referred to as metal-free phthalocyanine particles 5.

The obtained metal-free phthalocyanine particles 1 to 5
Are shown in Table 1. Further, as described later, the metal-free phthalocyanine particles 1 to 5 (the metal-free phthalocyanine particles 1 after toner formation) which are incorporated as a colorant in the toner.
To 5) and the characteristic values of the metal-free phthalocyanine particles 1 used in the preparation of the comparative toner.

[0239]

[Table 1]

From Table 1, it is apparent that the metal-free phthalocyanine particles incorporated into the toner of the present invention have a low conversion rate to α-form.

<< Preparation of Colorant Dispersions 1 to 5 >> 59.0 g of sodium n-dodecyl sulfate was added to 1600 m of deionized water.
while stirring the solution, gradually adding the metal-free phthalocyanine particles 1 (270.0 g in terms of solid content) while stirring the solution, and then using “CLEARMIX” (manufactured by M Technique Co., Ltd.). By performing a dispersion treatment, a dispersion of colorant particles (hereinafter, referred to as “colorant dispersion 1”) was prepared. The particle size of the colorant particles in this colorant dispersion was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.).
nm.

Further, colorant dispersions 2 to 5 were prepared in the same manner except that metal-free phthalocyanine particles 2 to 5 shown in Table 1 were used instead of metal-free phthalocyanine particles 1.

<< Preparation of Latex >> [Preparation of Latex 1HML] (1) Preparation of core particles (first-stage polymerization): 5000 m equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introducing device.
In a 1 l separable flask, 7.08 g of the following anionic surfactant (101) was added to 3010 g of ion-exchanged water.
The solution in the flask was charged with a surfactant solution (aqueous medium), and the temperature in the flask was raised to 80 ° C. while stirring at a stirring speed of 230 rpm in a nitrogen stream.

(101) C ₁₀ H ₂₁ (OCH ₂ CH ₂ ) ₂ O
SO ₃ Na A polymerization initiator (potassium persulfate) is added to this surfactant solution.
An initiator solution prepared by dissolving 9.2 g in ion-exchanged water (200 g) was added, and the temperature was adjusted to 75 ° C.
g, 19.9 g of n-butyl acrylate and 10.9 g of methacrylic acid were added dropwise over 1 hour, and the system was heated and stirred at 75 ° C. for 2 hours to carry out polymerization (first stage). Polymerization) to prepare a latex (a dispersion of resin particles composed of a high molecular weight resin). This is designated as “latex (1H)”.

(2) Formation of Intermediate Layer (Second Stage Polymerization): In a flask equipped with a stirrer, styrene 10
As a crystalline substance, a monomer mixture comprising 5.6 g, 30.0 g of n-butyl acrylate, 6.2 g of methacrylic acid, and 5.6 g of n-octyl-3-mercaptopropionate was used as a crystalline substance in Table 19). Compound (hereinafter, referred to as
It is referred to as "exemplary compound 19." 9) 9g was added and 9
The mixture was heated to 0 ° C. and dissolved to prepare a monomer solution.

On the other hand, an anionic surfactant (101)
A surfactant solution obtained by dissolving 1.6 g in 2700 ml of ion-exchanged water was heated to 98 ° C.
After adding 28 g of the latex (1H), which is a dispersion liquid of core particles, in terms of solid content, the dispersion was mechanically dispersed using a mechanical disperser “CLEARMIX (CLEARMIX)” (manufactured by M Technique Co., Ltd.). The monomer solution of the compound 19 was mixed and dispersed for 8 hours to prepare a dispersion liquid (emulsion liquid) containing emulsified particles (oil droplets).

Next, an initiator solution in which 5.1 g of a polymerization initiator (KPS) was dissolved in 240 ml of ion-exchanged water and 750 ml of ion-exchanged water were added to the dispersion (emulsion). Polymerization (second-stage polymerization) is carried out by heating and stirring at 12 ° C. for 12 hours, and latex (a dispersion of composite resin particles having a structure in which the surface of resin particles made of a high molecular weight resin is coated with an intermediate molecular weight resin) is used. Obtained. This is referred to as “latex (1HM)”.

The latex (1HM) was dried and observed with a scanning electron microscope. As a result, particles (400%) mainly composed of Exemplified Compound 19 which were not surrounded by the latex were observed.
nm-1000 nm) was observed.

(3) Formation of outer layer (third stage polymerization): An initiator obtained by dissolving 7.4 g of a polymerization initiator (KPS) in 200 ml of ion-exchanged water in the latex (1HM) obtained as described above. The solution was added, and a monomer mixture consisting of 300 g of styrene, 95 g of n-butyl acrylate, 15.3 g of methacrylic acid, and 10.4 g of n-octyl-3-mercaptopropionate was added under a temperature condition of 80 ° C.
It was dropped over time. After completion of the dropping, polymerization (third stage polymerization) is carried out by heating and stirring for 2 hours.
Cooled to 8 ° C., a latex (a composite resin having a central portion composed of a high molecular weight resin, an intermediate layer composed of an intermediate molecular weight resin, and an outer layer composed of a low molecular weight resin, wherein the intermediate layer contains Exemplified Compound 19) Particles). This latex is referred to as “latex (1HML)”. The composite resin particles constituting this latex (1HML) are 13
It had peak molecular weights at 8,000, 80,000 and 13,000, and the composite resin particles had a weight average particle size of 122 nm.

<< Production of Toner >> (Production of Toner 1) Latex (1HML) 420.7
g (in terms of solid content), 900 g of ion-exchanged water, and 166
g of the colorant dispersion liquid 1 was stirred in a reaction vessel (four-necked flask) equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a stirring device. After adjusting the temperature in the container to 30 ° C., a 5 mol / liter aqueous sodium hydroxide solution was added to the solution to adjust the pH to 9.0.

Next, magnesium chloride hexahydrate 1
An aqueous solution in which 2.1 g was dissolved in 1,000 ml of ion-exchanged water was added over 10 minutes at 30 ° C. with stirring. After standing for 3 minutes, the temperature was raised, and the temperature of the system was raised to 90 ° C. over 60 minutes, so that coagulation and fusion proceeded simultaneously. In this state, the particle size of the associated particles was measured with a “Coulter counter TA-II”, and when the number average particle size became 4 μm, 80.4 g of sodium chloride was added to ion-exchanged water 10
An aqueous solution dissolved in 00 ml was added to stop the particle growth, and the solution was further ripened at a liquid temperature of 85 to 98 ° C. for 2 to 1 hour.
By heating and stirring for 2 hours, the fusion of the particles and the phase separation of the crystalline substance were continued (ripening step).

Thereafter, the mixture was cooled to 30 ° C., the pH was adjusted to 2.0 by adding hydrochloric acid, and the stirring was stopped. The formed associated particles are filtered, washed repeatedly with ion exchanged water at 45 ° C., and then dried with warm air at 40 ° C.
Colored particles 1 were obtained.

The obtained colored particles 1 were mixed with hydrophobic silica 0.1.
8 parts by mass and 1.0 part by mass of hydrophobic titanium oxide were added,
The peripheral speed of the rotor of the 0 liter Henschel mixer is 30
m / s and mixed for 25 minutes. The obtained toner is referred to as toner 1.

Also, in the same manner as in the case of using the colorant dispersion liquids 2 to 5 instead of the colorant dispersion liquid 1,
Was prepared, and then external additives were similarly added, thereby producing toners 2 to 5 shown in Table 2.

In the production of the toners 1 to 5, the shape and particle size of the above-mentioned colored particles are not changed at all by the addition of the external additive.

(Production of Comparative Toner 1) The water-wet paste of the metal-free phthalocyanine particles 1 was dried and dried using a flash jet drier, and the metal-free phthalocyanine particles 1 were dried.
A powder was obtained.

Styrene acrylic resin 100 parts Metal-free phthalocyanine particles 1 powder (the physical properties are described in Table 1) 6 parts Exemplified compound 19 8 parts The above materials are premixed with a Henschel mixer, extruded and kneaded with a twin screw, and jet milled. Then, 0.8 parts by mass of hydrophobic silica and 1.0 parts by mass of hydrophobic titanium oxide were added, and the peripheral speed of the rotating blade of the Henschel mixer was set to 30 m / s, and the mixture was added. After mixing for 1 minute, Comparative Toner 1 was obtained.

Tables 2 and 3 show the preparation methods of the toners 1 to 5 and the comparative toner 1 obtained above, and their characteristic data.
Shown in

[0259]

[Table 2]

[0260]

[Table 3]

<< Preparation of Photoconductor P1 >> The following coating solution was applied onto a cylindrical conductive support having a length of 380 mm and a diameter of 60 mm to prepare photoconductor P1.

<Undercoat layer> Titanium chelate compound (TC-750: manufactured by Matsumoto Pharmaceutical Co., Ltd.) 30 g Silane coupling agent (KBM-503: manufactured by Shin-Etsu Chemical Co., Ltd.) 17 g 2-propanol 150 ml Cylindrical conductive using the above coating solution Film thickness of 0.
It was applied so as to have a thickness of 5 μm.

<Coating of Charge Generation Layer> Y-type titanyl phthalocyanine (Cu-Kα characteristic X-ray diffraction spectrum measurement, titanyl phthalocyanine having a maximum peak at 27.2 ° at a Bragg angle 2θ (± 0.2 °)) 60 g) Silicone-modified butyral resin (X-40-1211M: manufactured by Shin-Etsu Chemical Co., Ltd.) 700 g 2-butanone 2000 ml The above materials were mixed and dispersed using a sand mill for 10 hours to prepare a charge generation layer coating solution. This coating solution was applied on the undercoat layer by a dip coating method to form a charge generation layer having a thickness of 0.2 μm.

<Coating of Charge Transport Layer> Charge transport material N- (4-methylphenyl) -N- {4- (β-phenylstyryl) phenyl} -p-toluidine 225 g Polycarbonate (viscosity average molecular weight 30,000) 300 g Antioxidant (Exemplified Compound 1-3) 6 g Dichloromethane 2000 ml The above materials were mixed and dissolved to prepare a charge transport layer coating solution. This coating solution was applied on the charge generation layer by a dip coating method to form a charge transport layer having a dry film thickness of 20 μm.

<Coating of Protective Layer> Methyltrimethoxysilane 150 g Dimethyldimethoxysilane 30 g Reactive charge transporting compound (Exemplified Compound B-1) 15 g Polyvinylidene fluoride particles (volume average particle size 0.2 μm) 10 g Antioxidant (Exemplified Compound 2-1) 0.75 g 2-propanol 75 g 3% acetic acid 5 g

[0266]

Embedded image

[0267]

Embedded image

[0268]

Embedded image

The above materials were mixed to prepare a coating liquid for a resin layer. A 2 μm thick resin layer was formed on the charge transporting layer by using a circular amount controlling type coating apparatus.
A siloxane resin layer was formed by heating and curing at 0 ° C. for 1 hour, to thereby produce a photoconductor P1.

As a copying machine employing a non-magnetic one-component developing method as an evaluation machine, a digital copying machine having an image forming process shown in FIG. 5 (corona charging, laser exposure, reversal development, electrostatic transfer, nail separation, cleaning) (With a blade), the photoreceptor P1 and the toner described above were directly mounted as a developer and evaluated. The above digital copying machine was evaluated under the following conditions.

(Charging Conditions) Charger: Scorotron charger, initial charging potential was -750
Adjusted to V (Exposure condition) Set the exposure amount to make the exposure part potential -50V.

(Developing conditions) DC bias; -550 V Transfer pole; corona charging system The fixing device shown in FIG. 6 was used. The linear velocity was 120 mm / sec, and the fixing device cleaning mechanism and the silicone oil supply mechanism were not mounted.
The fixing temperature is controlled by the surface temperature of the heating roller.
Was set.

The copying conditions are as follows: high temperature and high humidity environment (30 ° C., 80
% RH), and evaluated according to the following evaluation criteria.

In the evaluation, a character image having a pixel ratio of 7%, a portrait image of a person, a solid white image, and an original image having a solid black image, each of which is １ ／, are copied on A4 neutral paper.
Blueness, image transparency, image density, fog, halftone uniformity, fine dot dust, etc. were evaluated.

<< Evaluation Items >> (Blueness) The blueness of the obtained image was measured for a * and b * using a colorimeter (Macbeth Color Eye), and the rank was evaluated as follows.

A: Cyan color highly preferred in both chroma and lightness (a *: -10 to +10, b *: -50 to -60) A: Cyan color slightly greenish (a *: -20) ~-
10 or 10 to 20, b *: −40 to −50) ×: Reddish or brownish, cloudy cyan (a *: −)
(Less than 15 or more than +15, b *: more than -40) Regarding the evaluation ranks, ◎ and ○ were practically usable, and × was impractical.

(Transparency of Image (Transparency)) As the transparency of the image, the transparency of the OHP image was used. In particular,
On the OHP, the toner adhesion amount is 0.7 ± 0.05 (mg /
cm ² ), a transmission image (OHP image) was prepared (fixing temperature: 170 ° C.), and toner was carried on the fixed image by “330-type self-recording spectrophotometer” manufactured by Hitachi, Ltd. The visible spectral transmittance of the image was measured using an OHP sheet without
And the spectral transmittance at 600 nm were determined and used as a measure of the transparency of the OHP image.

For the evaluation, the following rank evaluation was performed. ◎: 85% or more ○: 70 to 85% ×: less than 70% When the transmittance value is 70% or more, good transmittance is obtained.

(Evaluation of Image Density) The Macbeth reflection density in a 20 mm × 20 mm solid image portion was measured. The density was evaluated from the numerical values of the reflection density as follows.

◎: 1.35 or more ： １: 1.30 to 1.35 (practicable) ×: less than 1.30 (not practical) (fog (fog in high temperature and high humidity environment)) 30 ° C., 80% R
After printing 100,000 sheets of H, the fog of the image was visually evaluated as follows.

◎: no fog, good ○: slight fog, but practically feasible X: remarkably fog (not practical) (halftone uniformity) Halftone due to fluctuation of transferability after continuous 500,000 copies described above The uniformity of the image was visually evaluated and ranked as follows.

A: Uniform image without unevenness B: Extremely thin streak-like unevenness present C: Several streak-like thin unevennesses exist, but practically no problem (practicable) D: Clear streak-like unevenness Several or more nonuniformities exist (impractical) (fine dot dust) A 10% halftone dot image was formed on the entire surface of the image, and dust around the dots was visually observed with a loupe, and ranked as follows.

A: Chile was hardly detectable O: Slight chile was found X: Chile was easily detectable Table 4 shows the obtained evaluation results.

[0284]

[Table 4]

From Table 4, it is apparent that the sample of the present invention is more excellent in bluishness, image transparency, image density, fog, uniformity of halftone and less generation of fine dot dust as compared with the comparison. It is.

[0286]

According to the present invention, blue (cyan) color saturation, image transparency, image density are high, fog under high temperature and high humidity conditions is reduced, halftone uniformity is excellent, and It is possible to provide a toner for developing an electrostatic image, in which dust of fine dots is less generated, a method for manufacturing the toner, and an image forming method using the toner.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an example of toner particles according to the present invention divided by a Voronoi polygon (Voronoi polyhedron).

FIG. 2 is a schematic view showing an example of an embodiment of an image forming apparatus used in the present invention.

FIG. 3 is a schematic cross-sectional view of a developing device for explaining a developing method of the present invention and a cross-sectional view of a main part thereof.

FIG. 4 is an example of a perspective configuration diagram of a toner recycling member used in the present invention.

FIG. 5 is a schematic configuration diagram illustrating an example of a color electrophotographic image forming apparatus.

FIG. 6 is a sectional view showing an example of a fixing device used in the present invention.

FIG. 7 is a schematic diagram illustrating a toner without a corner or with a corner.

[Description of Signs] 1a, 1b, 1c, 1d Electrostatic latent image carrier (photosensitive drum) 2a, 2b, 2c, 2d Drum charger 3a, 3b, 3c, 3d Developing device 4a, 4b, 4c, 4d Transfer Charger 41a, 41b, 41c, 41d Transfer pressing member 5a, 5b, 5c, 5d Photoconductor cleaning unit 10 Fixing unit (fixing device) 17 Laser beam exposure device 21a, 21b, 21c, 21d Static elimination exposure lamps 22a, 22b, 22c , 22d Potential sensors Pa, Pb, Pc, Pd Image forming section 8 Image carrier 11 Core 12 Heating roller 12a Covering layer of heating roller 13 Heating member 20 Pressure roller 21 Core 22 Coating layer of pressure roll T Toner image 71 Heating roller 72 Pressure roller 73, 74 Heat resistant cleaning member 75, 76 Heater 77 Oil application roller 78 Oil Le Reservoir 79 Thermistor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Meisho Shirase 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H005 AA08 AA21 AB02 AB06 CA21 CB07 CB13 EA05 EA07 FA07

Claims (9)

[Claims] 1. An electrostatic image containing toner particles obtained by forming colored particles containing a binder resin and a colorant in an aqueous medium and then adding and mixing metal oxide particles to the colored particles. A toner for developing an electrostatic image, wherein the colorant comprises metal-free phthalocyanine. 2. The metal-free phthalocyanine contains 70% by mass or more of β-type metal-free phthalocyanine and 30% by mass or less of α-type metal-free phthalocyanine.
3. The toner for developing an electrostatic image according to item 1. 3. The metal-free phthalocyanine contains 85% by mass or more of β-type metal-free phthalocyanine and 15% by mass or less of α-type metal-free phthalocyanine.
3. The toner for developing an electrostatic image according to item 1. 4. The electrostatic image developing toner according to claim 1, further comprising 10 to 5000 ppm of a phthalimide derivative or a phthalonitrile derivative. 5. The toner contains toner particles having a number average particle diameter of 2 to 6 μm and 6 to 12% by mass of a metal-free phthalocyanine, and the metal-free phthalocyanine has an average Feret horizontal diameter of 10 to 30 nm. 5. The electrostatic image developing toner according to claim 1, wherein the toner is dispersed in the toner particles such that the coefficient of variation of the horizontal diameter of the ferrite is 30% or less. 6. The method for producing the toner for developing an electrostatic image according to claim 1, wherein the toner particles are produced through the following steps (1) to (3). Of producing a toner for developing electrostatic images. (1) A metal-free phthalocyanine water-wet paste is diluted and dispersed in an aqueous medium to prepare metal-free phthalocyanine particles. (2) The metal-free phthalocyanine particles are dispersed in a binder resin as a colorant to produce colored particles. Then, (3) a metal oxide is added to and mixed with the colored particles to produce toner particles. 7. The method for producing a toner for developing an electrostatic image according to claim 6, further comprising a step of salting out, aggregating, and fusing the resin particles and the metal-free phthalocyanine particles in an aqueous medium. 8. The electrostatic image according to claim 6, further comprising a step of salting out, aggregating, and fusing the composite resin particles obtained by the multistage polymerization method and the metal-free phthalocyanine particles. A method for producing a developing toner. 9. A developing roll, and a toner supply member for supplying toner onto the development roll, a non-magnetic toner being supplied to the development roll from the toner supply member, and a toner layer formed on the development roll being formed. 9. An image forming method using a one-component developing device for performing development using a toner, wherein the non-magnetic toner is the toner for developing an electrostatic image according to any one of claims 1 to 5 or the toner according to any one of claims 6 to 8. 14. An image forming method, comprising using the electrostatic image developing toner according to any one of the above.