JP2003084499A - Electrostatic charge image developing toner, method for manufacturing the toner and method for forming image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner having high transmitting property, uniformity of the halftone, preferable sharpness in an image, no offset during fixing, low fog and no filming on a photoreceptor and to provide a method for manufacturing the toner and a method for forming an image. SOLUTION: In the electrostatic charge image developing toner manufactured in the process of forming the toner particles in a water-based medium, the toner particles are formed by dispersing a chromatic pigment having 40 to 20,000 ppm tetrahydrofuran-eluted content in a water-based medium and then using the obtained dispersion liquid as a component to constitute the coloring agent. The toner particles have 3.0 to 7.5 μm volume average particle size and 0.945 to 0.985 circularity.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art In recent years, a polymerized toner obtained by a suspension polymerization method or an emulsion polymerization method has a uniform distribution with a small particle size because the particle size and shape of the toner can be controlled in a polymerization process in an aqueous medium. It has been disclosed in JP-A-2000-214629 that a toner having rounded corners on particles can be obtained, and attention is paid to it as a toner capable of reproducing small dot images for digital images due to its fine line reproducibility and high resolution. Has been done.

However, it is known that the dispersibility of the colorant added to the toner is more likely to deteriorate in the polymerized toner than in the pulverized toner. This is due to the suspension polymerization method.
Polymerization is performed after dispersing the pigment that is a colorant in the monomer, but the aggregation of the colorant easily occurs because the viscosity of the monomer droplets increases with the progress of polymerization, and in the emulsion polymerization method, the aggregation or aggregation step is performed. Since the influence of pH or the like promotes the aggregation of the colorant, there is a problem that the aggregation of the colorant is likely to occur.

As described above, the polymerized toner has a problem that the dispersibility of the polymerized toner is apt to deteriorate because the colorant is apt to aggregate in the manufacturing process.

On the other hand, Japanese Patent Laid-Open No. 2000-292973.
In this issue, the technology for improving the dispersion of the colorant has been positively examined, but the technology that has not solved the dispersibility of the colorant is still insufficient. A certain degree of transparency is required to form a color image by superimposing toners, but the transparency is a serious problem especially when an image is formed on an OHP film.

It is generally well known that the state in which the colorant is added to the toner particles has a great influence on the toner performance such as the resolution.
No. 81735 and Japanese Patent Laid-Open No. 2000-284540, the ratio of the major axis to the minor axis of the colorant used in the pulverized toner and the number average diameter are specified to improve the dispersibility of the colorant in the toner and to achieve good color reproduction. However, these do not indicate the state of the colorant in the toner particles, but specify the colorant before addition to the toner particles. .

Further, the colorant dispersed state in the toner particles is not transparent when the colorant is uniformly dispersed without taking a phase separation structure such as a sea-island structure in the toner particles or a structure in which the colorant is aggregated. Although it is excellent, the charge retention function tends to be lowered, and those having a phase-separated structure or aggregates have a problem that they have a good charge retention function but poor light transmission.

Therefore, Japanese Patent Laid-Open No. 5-88409 discloses an encapsulated toner in which a colorant is aggregated in a particle and a resin is wrapped around the encapsulated toner. The structure of the toner provides good light transmission and electric charge. Although it was expected to have both a holding function, the expected transparency could not be obtained because light scattering occurs at the interface between the colorant region and the resin.

Further, when the colorant of the polymerized toner is dispersed, there are many agglomerations, and there are problems in stability of charging and transparency of the image in the color toner. The cause is that a commercially available toner colorant is used for so-called pulverized toner in which toner particles are formed by kneading, pulverizing, and classifying, so that the colorant is treated with a resin such as rosin and a surfactant. Can be mentioned. That is, after dispersing the colorant particles in the aqueous medium using a dispersant such as a surfactant,
In the toner produced through the step of aggregating with the resin particles, or mixing with the resin solution and the polymerizable monomer,
There is a problem that the conventionally known treatment with the colorant rather accelerates the aggregation of the colorant.

Another problem is that a low molecular weight organic compound, which is a by-product at the time of synthesizing the colorant, is present on the surface of the colorant, which tends to hinder the dispersion stability of the colorant dispersion.

From the above, there has been a demand for a polymerized toner having a good charge retention function and sufficient transparency.

[0012]

The object of the present invention is to provide an OH
Toner for developing an electrostatic charge image having high P transparency, good halftone uniformity, good image sharpness, no fixing offset, low fog, and no filming on the photoreceptor. A method for producing the toner and an image forming method are provided.

[0013]

The above objects of the present invention have been achieved by the following constitutions 1 to 13.

1. A toner for developing an electrostatic image, comprising toner particles containing a binder resin and a colorant, the toner particles being formed in a water-based medium, and having a tetrahydrofuran elution content of 40 ppm to 20,000 p.
The chromatic pigment of pm is dispersed in an aqueous medium, the obtained dispersion is used as a component constituting the colorant to form the toner particles, and the volume average particle diameter of the toner particles is 3 0.0 μm to 7.5 μm, and the circularity is 0.
A toner for developing an electrostatic charge image, characterized in that it is 945 to 0.985.

2. Chromatic pigment is 50ppm of divalent metal
1 to 10,000 ppm
The toner for developing an electrostatic image as described in 1.

3. 3. The electrostatic charge image developing toner as described in 1 or 2 above, wherein the chromatic color pigment is a water wet paste.

4. The binder resin of the toner particles and the colorant constitute a sea-island structure, and the average value of the area of Voronoi polygons formed by the perpendicular bisectors between the centers of gravity of adjacent islands in the sea-island structure is 20, 000 nm ^{2 to} 120,000 nm ²
And the coefficient of variation of the area of the Voronoi polygon is 2
The toner for developing an electrostatic charge image according to any one of 1 to 3, which is 5% or less.

5. 4. The toner for developing an electrostatic charge image according to any one of 1 to 3 above, wherein the chromatic color pigment contains a compound represented by the general formula (1).

6. A chromatic pigment contains a compound represented by the general formula (1) and a compound represented by the general formula (2), and the electrostatic image according to any one of 1 to 5 above. Toner for development.

7. 7. The toner for developing an electrostatic charge image according to any one of 1 to 6 above, wherein the chromatic color pigment contains a compound represented by the general formula (3).

8. The toner for developing an electrostatic image according to any one of 1 to 7 above, which contains 8.2 kinds of surfactants.

9. In producing the toner for developing an electrostatic charge image according to any one of 1 to 8 above, a chromatic pigment having a tetrahydrofuran elution content of 40 ppm to 20,000 ppm has a weight average particle diameter of 30 in an aqueous medium.
A method for producing a toner for developing an electrostatic charge image, comprising: a step of preparing toner particles using a dispersion liquid having a particle size of 0 nm or less; and a step of separating the toner particles from an aqueous medium.

10. Chromatic pigment is 50p for divalent metal
10. The method for producing an electrostatic charge image developing toner as described in 9 above, wherein the toner contains pm to 10,000 ppm.

11. Dispersing a binder resin in the presence of an anionic surfactant A to prepare a dispersion A of the binder resin, dispersing a colorant in the presence of an anionic surfactant B to disperse the colorant. B and a step of mixing the dispersion liquid A and the dispersion liquid B in the presence of the anionic surfactant C and then salting out / fusing the mixture, the anionic surfactant A,
11. The method for producing an electrostatic charge image developing toner as described in 9 or 10 above, wherein at least one of B and C has a molecular structure different from that of the other two.

12. A latent image forming step of forming a latent image on the latent image carrier, a developing step of developing the latent image with toner, and a toner image formed on the latent image carrier on a transfer target. In the image forming method including a transfer step of transferring and a fixing step of heating and fixing the toner image on the transfer target using a heating member and a pressing member,
9. The toner for developing an electrostatic image according to any one of item 8, wherein the heating member has an elastic layer.

13. 13. The image forming method as described in 12 above, wherein at least one of the heating member and the pressing member is a belt.

The present invention will be described in detail below. The present inventors have conducted various studies on the above-mentioned problems, and as a result of paying attention to the dispersibility of the colorant dispersion liquid in the process of producing a polymerized toner and dispersion stability, when forming toner particles in an aqueous medium, Tetrahydrofuran elution content is 40 ppm to 20,000 pp
The chromatic color pigment of m is dispersed in an aqueous medium as a component of the colorant to form toner particles, and the volume average particle diameter of the toner particles is from 3.0 μm to
It has been found that the effects described in the present invention can be obtained by using a toner for developing an electrostatic charge image, which is adjusted to have a circularity of 7.5 μm and a circularity of 0.945 to 0.985.

The colorant according to the present invention will be described. A chromatic pigment is used as the colorant according to the present invention,
From the viewpoint of obtaining the effect described in the present invention, the elution amount of tetrahydrofuran of the pigment is 40 ppm to 20,000 ppm.
It is necessary to be in the range of, but preferably 50 p
It is pm-10,000 ppm. Here, the measuring method of tetrahydrofuran elution is shown below.

<< Measurement Method of Tetrahydrofuran Soluble Content >>
The tetrahydrofuran elution amount in the chromatic pigment can be measured, for example, as follows. Pigment composition 100
g with 300 g of tetrahydrofuran and stirred, and then 1
After centrifuging at 6,000 rpm for 30 minutes, the obtained supernatant is collected. The same operation is repeated 3 times for the precipitate. After collecting all the supernatants and concentrating to dryness with a rotary evaporator, the dry solids are weighed and the eluate of tetrahydrofuran is determined. For weighing dry matter,
Multifunctional Analytical Balance AX205 (METTLER TOLEDO CORPORATION)
Manufactured) was used.

The tetrahydrofuran elution content of the chromatic pigment used as the colorant according to the present invention is 40 ppm to 2
The following treatments are preferably carried out in order to adjust the concentration within the range of 10,000 ppm.

<< Preparation Method of Tetrahydrofuran Elution Content >> (1) A very small amount of surface treatment (rosin treatment, salt treatment) is applied at the time of synthesizing a colorant (chromatic pigment), and (2) A large amount of surface-treated product is commercially available. Examples include treatment methods such as washing a conventionally known coloring agent with a solvent, (3) selecting a synthesis and purification method so that an organic substance as a by-product falls within the scope of the present invention, and not performing surface treatment. To be

In the present invention, the treatments (1) and (2) are preferable among the above (1) to (3), and the treatments described in (1) to (3) may be combined. good.

Next, the specific contents of the processing will be described. Specific method of (1) When the surface treatment of the azo pigment is performed with rosin, after completion of the coupling reaction between the diazotised amine and the coupler component, an aqueous solution of various rosin sodium salts is added to the reaction solution. Further, calcium chloride or barium chloride is added to form an insoluble rosin salt, which coats the surface of the pigment. The rosin may be acidified with a mineral acid or the like instead of being a metal salt to coat the surface of the pigment, but the azo pigment treated with a so-called metal-free rosin that is not a metal salt is more stable in dispersibility. Excellent and preferable. Rosin is a natural resin called pine resin and has abietic acid as a main component.
As the rosin, gum rosin, polymerized rosin, disproportionated rosin, hydrogenated rosin, maleated rosin, fumarized rosin, wood rosin and the like can be used.

Specific method of (2) The solvent used is preferably methanol, ethanol, benzene, toluene, xylene, acetone, diethyl ether or tetrahydrofuran. The washing conditions are not particularly limited, but the washing is carried out while monitoring the tetrahydrofuran-soluble content of the washed product to adjust the tetrahydrofuran elution amount to 40 ppm to 20,000 ppm.

The chromatic color pigment according to the present invention will be described. As the chromatic pigment according to the present invention, the compounds represented by the general formulas (1) to (3) are preferably used.

The compounds represented by the above general formulas (1) and (2) according to the present invention will be described. General formula (1),
In (2), the alkyl group having 1 to 3 carbon atoms represented by X ₁ , X ₂ , X ₃ , Y ₁ , Y ₂ and Y ₃ may be unsubstituted or may have a substituent. Examples thereof include a methyl group, an ethyl group, an isopropyl group, and a propyl group.

In the general formulas (1) and (2), X ₁ ,
_{X 2, X 3, Y 1} , Y 2 and 1-3 carbon atoms represented by Y ₃
Examples of the fluoroalkyl group include a methyl group, an ethyl group, an isopropyl group and a propyl group each having at least one fluorine atom. The above group may further have a substituent.

In the general formulas (1) and (2), X ₁ ,
The alkoxyl group represented by X ₂ , X ₃ , Y ₁ , Y ₂ and Y ₃ may be unsubstituted or may have a substituent,
For example, a methoxy group, an ethoxy group, a propoxy group and the like can be mentioned.

In the general formulas (1) and (2), X ₁ ,
Examples of the pigeon atom represented by X ₂ , X ₃ , Y ₁ , Y ₂ and Y ₃ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

In the general formulas (1) and (2), X ₁ ,
Examples of the higher amine salt of the sulfo group represented by X ₂ , X ₃ , Y ₁ , Y ₂ and Y ₃ include amines having 4 or more carbon atoms, such as butylamine, cyclohexylamine, naphthylamine, aniline, anisidine, phenetidine, Examples include toluidine and xylidine.

In the general formulas (1) and (2), X ₁ ,
Examples of the alkoxycarbonyl group represented by X ₂ , X ₃ , Y ₁ , Y ₂ and Y ₃ include a methoxycarbonyl group,
Examples thereof include an ethoxycarbonyl group.

In the general formulas (1) and (2), X ₁ ,
-CONHR ₁ represented by X ₂ , X ₃ , Y ₁ , Y ₂ and Y _3.
As the alkyl group having 1 to 8 carbon atoms represented by R ₁ , a methyl group, an ethyl group, a propyl group, a pentyl group,
Hexyl group, octyl group and the like can be mentioned.

In the general formulas (1) and (2), X ₁ ,
-NHCOR ₂ represented by X ₂ , X ₃ , Y ₁ , Y ₂ and Y _3.
As the alkyl group represented by R ₂ , for example,
Examples thereof include a methyl group, an ethyl group, a propyl group, a pentyl group, a hexyl group, an octyl group and a decyl group.

In the general formulas (1) and (2), X ₁ ,
Examples of —SO ₂ R ₃ represented by X ₂ , X ₃ , Y ₁ , Y ₂ and Y ₃ include an alkyl group having 1 to 8 carbon atoms represented by R ₃ , such as a methyl group, an ethyl group, Examples thereof include a propyl group, a pentyl group, a hexyl group and an octyl group.

Specific examples of the compound represented by the general formula (1) and specific examples of the compound represented by the general formula (2) are shown below, but the present invention is not limited thereto.

[0046]

[Chemical 4]

[0047]

[Chemical 5]

The compounds represented by the general formulas (1) and (2) according to the present invention can be synthesized by referring to conventionally known methods for synthesizing monoazo pigments and methods described in JP-A-10-171165. You can

The compound represented by formula (3) according to the present invention will be described. In the general formula (3), R ₂ ,
Examples of the alkyl group represented by R ₃ , R ₄ , and R ₅ include, for example, a branched or straight-chain alkyl group having 1 to 10 carbon atoms (eg, methyl group, ethyl group, propyl group, butyl group, pentyl group). , Iso-pentyl group, 2-ethylhexyl group, octyl group, decyl group, etc.).

In the general formula (3), R ₂ , R ₃ , R ₄ ,
Examples of the alkoxyl group represented by R ₅ include a methoxy group, an ethoxy group, a propoxy group and the like.

In the general formula (3), R ₂ , R ₃ , R ₄ ,
Examples of the halogen atom represented by R ₅ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

In the general formula (3), R ₂ , R ₃ , R ₄ ,
Examples of the alkoxycarbonyl group represented by R ₅ include an ethoxycarbonyl group and a butoxycarbonyl group.

In the general formula (3), R ₂ , R ₃ , R ₄ ,
Examples of the acyl group represented by R ₅ include an acetyl group and a benzoyl group.

In the general formula (3), R ₂ , R ₃ , R ₄ ,
Examples of the acylamino group represented by R ₅ include an acetylamino group and a benzoylamino group.

In the general formula (3), R ₂ , R ₃ , R ₄ ,
Examples of the alkylthio group represented by R ₅ include a methylthio group and an ethylthio group.

In the general formula (3), R ₂ , R ₃ , R ₄ ,
Examples of the aryl group represented by R ₅ include a phenyl group and a naphthyl group.

In the general formula (3), R ₂ , R ₃ , R ₄ ,
Examples of the aryloxy group represented by R ₅ include a phenoxy group and a p-tolyloxy group.

Specific examples of the compound represented by formula (3) according to the present invention are shown below, but the present invention is not limited thereto.

[0059]

[Chemical 6]

The compounds represented by the general formula (3) according to the present invention, like the compounds represented by the general formulas (1) and (2), refer to conventionally known methods for synthesizing monoazo pigments. hand,
It can be synthesized.

As the colorant according to the present invention, a conventionally known colorant (also referred to as a pigment or a chromatic color pigment) which will be described later can be used, but the effect described in the present invention can be more preferably exerted and an image From the viewpoint of improving heat resistance and obtaining good image transparency without dullness, it is preferable to use the compound represented by the general formula (1), and more preferably, the compound represented by the general formula (1) Use in a mixture with the compound represented by the general formula (2) or use of the compound represented by the general formula (3) (referred to as a benzimidazolone compound). Among the compounds represented by the general formula (3), C.I. I. Pigme
Nnt Yellow 180.

The content of the chromatic color pigment according to the present invention in the toner is preferably 1 part by mass to 20 parts by mass, and more preferably 4 parts by mass to 12 parts by mass with respect to the binder resin.

When the compounds represented by the general formula (1) and the general formula (2) are used in combination, 99.8 mol% to 80 mol% of the compound represented by the general formula (1), It is preferable that 0.2 mol% to 20 mol% of the compound represented by 2) is mixed during the pigment synthesis.

The chromatic color pigment according to the present invention preferably contains 50 ppm to 10,000 ppm of a divalent metal, more preferably 80 ppm to 50,000 ppm.
Is. Examples of the divalent metal include salts of alkaline earth metals such as calcium and magnesium, divalent metal salts such as manganese and copper, and trivalent metal salts such as iron and aluminum. Specific examples of the metal salt of these divalent metals include magnesium chloride, calcium chloride, calcium nitrate, zinc chloride, copper sulfate, magnesium sulfate, manganese sulfate and the like, but the present invention is not limited thereto. Further, the above metal salt is appropriately selected according to the purpose.

Here, the method for measuring the metal element in the pigment is wetted as follows. << Measuring Method of Amount of Metal Element in Pigment >> The content ratio of the specific element in the pigment composition can be measured by using a conventionally known elemental analysis method, but a simple and accurate numerical value can be obtained. Therefore, the fluorescent X-ray analysis method is preferably used. Specifically, by performing a qualitative analysis of the elements in the toner using fluorescent X-rays, creating a calibration curve for the detected specific elements, and performing a quantitative analysis of the specific elements from this calibration curve, The content ratio of the specific element in the toner is calculated.

In the present invention, the above-mentioned chromatic color pigment is dispersed in an aqueous medium to prepare a component constituting the colorant. Specifically, the colorant is in the form of fine particles (also called colorant fine particles). Is preferred. Here, the colorant fine particles will be described.

[Colorant Fine Particles] The colorant fine particles preferably used for producing the toner of the present invention are formed by using a dispersing device for finely dispersing the colorant fine particles in an aqueous medium containing a surfactant. . That is, the dispersing device shown in FIG. 1 is an example of a dispersing device that finely disperses the colorant fine particles used in the production of the toner of the present invention. Generates a shearing force, and by the action of the shearing force (in addition, the action of collision force, pressure fluctuation, cavitation, and potential core), the colorant is finely dispersed in an aqueous medium containing a surfactant to obtain fine particles. It is a thing.

Here, the surfactant contained in the aqueous medium in which the colorant fine particles are dispersed has a critical micelle concentration (CMC).
The surfactant is dissolved at the above concentration, and the same surfactant as that used in the polymerization step can be used as the surfactant.

The weight average particle diameter (dispersed particle diameter) of the colorant fine particles is 30 nm to 500 nm from the viewpoint that the colorant particles are appropriately dispersed in an aqueous system to prevent sedimentation and facilitate the incorporation of the colorant into the toner particles. Is preferable, and more preferably 50 nm to 300 nm. The weight average particle diameter of the colorant fine particles is measured by an electrophoretic light scattering photometer "ELS-80".
0 "(manufactured by Otsuka Electronics Co., Ltd.).

The colorant fine particles used in the toner of the present invention are prepared by first preliminarily dispersing (coarse-dispersing) with a propeller stirrer or the like after introducing the colorant into an aqueous medium containing a surfactant. A predispersion liquid in which agglomerated particles are dispersed is produced. A preferable dispersion state is obtained by supplying the preliminary dispersion liquid to an agitator equipped with a screen for partitioning and forming an agitator chamber and a rotor rotating at high speed in the agitator chamber, and performing a dispersion treatment (fine dispersion treatment) by the agitator. A dispersion of fine colorant particles having is prepared.

In the present invention, as a stirring device for dispersion treatment for obtaining fine colorant particles having a preferable dispersion state, "CLEAR MIX" (manufactured by M Technique Co., Ltd.) can be mentioned. This "Clearmix" has a rotor (stirring blade) that rotates at high speed and a fixed screen (fixed ring) that surrounds the rotor, and applies shear force, collision force, pressure fluctuation, cavitation and It has a structure that imparts the action of a potential core, and these actions act synergistically to effectively emulsify and disperse the liquid to be treated.

That is, this "CLEAR MIX" is originally used for producing an emulsion (dispersion of liquid fine particles), but the present inventors have used for dispersing solid colorant fine particles in an aqueous medium. It was found that a dispersion of colorant fine particles having a preferable average particle size and a sharp particle size distribution can be obtained by using it as an apparatus.

FIG. 1A is a schematic view showing a rotor rotating at a high speed and a fixed screen surrounding the rotor. In FIG. 1A, 101 is a screen and M is a stirring section partitioned by the screen 101. A chamber and 102 are rotors that rotate at high speed in the stirring chamber M.

The rotor 102 is a stirring blade that rotates at a high speed, and its rotation speed is usually 4,500 to 22,000 rpm.
And preferably 10,000 to 21,500 rpm. The tip peripheral speed of the rotor 2 is usually 10 to 40 m / s.
ec, preferably 15 to 30 m / sec.

The screen 101 surrounding the rotor 102 is composed of a fixed ring composed of a large number of slits (not shown). The width of the slit is 0.5-5 mm
And preferably 0.8 to 2 mm. The number of slits is 10 to 50, preferably 15 to 30.
The clearance between the rotor 102 and the screen 101 is usually 0.1 to 1.5 mm, preferably 0.2.
~ 1.0 mm.

The average particle size and particle size distribution of the colorant fine particles are adjusted by controlling the rotation speed of the rotor 102, and can also be adjusted by selecting the shapes of the screen 101 and the rotor 102. Specifically, a screen (S1.0-24, S1.0-24, S1.0
1.5-24, S1.5-18, S2.0-18, S
3.0-9) and the rotors (R1 to R4) are combined to obtain a preferable dispersion state, but it is also possible to manufacture the resin by itself to obtain a more preferable dispersion state.

FIG. 1B is a schematic diagram showing a continuous processing apparatus (Clearmix) equipped with a rotor and a screen. The pre-dispersed dispersion liquid (pre-dispersion liquid) is supplied to the stirring chamber between the screen 101 and the rotor from the pre-dispersion liquid inlet 104 shown in FIG. The screen 101 and the rotor include a pressure vacuum attachment 10
It is surrounded by 3, and a temperature sensor 106, a cooling jacket 107 and a cooling coil 108 are arranged. The aggregated particles of the colorant in the pre-dispersion liquid are crushed (finely dispersed) by applying a shearing force generated by the rotor rotating at a high speed and the screen 101.

That is, the agglomerated particles of the colorant in the pre-dispersion liquid supplied to the zone-shaped stirring chamber between the screen 101 and the rotor are the shearing force (mechanical force) generated by the high speed rotation of the screen 101 and the rotor. Energy), and in addition to shearing force, it is disintegrated (finely dispersed) by the action of collision force, pressure fluctuation, cavitation, and potentiation core to become fine colorant particles. The dispersion liquid of fine colorant particles is ejected from the slit of the screen 101 into the pressure vacuum attachment 103 to obtain a dispersion liquid of fine colorant fine particles having a preferable average particle size and a sharp particle size distribution. The dispersion liquid containing the colorant fine particles is sent from the dispersion liquid outlet 5 to the next step.

By the action of the rotor and the screen, the colorant agglomerated particles are crushed into fine colorant particles (dispersed particles) having a preferable average particle size and a sharp particle size distribution in the stirring device. , Due to a plurality of actions described below.

(1) Since the velocity gradient is large near the surface of the rotor (stirring blade) rotating at a high speed, a high shear rate region is formed near the surface, and the shearing force generated in this region causes the aggregated particles of the colorant to be released. Be crushed.

(2) Behind the rotor (stirring blade), when the rotation speed is high, a vacuum portion (cavitation) is generated, and the bubbles generated by the rotation are extinguished at the stage where the flow velocity of the dispersion liquid decreases. An impact pressure is generated as the bubbles are compressed, and the impact pressure causes the aggregated particles of the colorant to be crushed.

(3) The rotor (stirring blade) gives pressure energy to the preliminary dispersion liquid by its high speed rotation, but when the pressure energy is suddenly released, the kinetic energy of the preliminary dispersion liquid increases and the preliminary dispersion liquid flows by the rotor. When the liquid repeatedly passes between the open part (slit part) and the closed part (non-slit part) of the screen, the pressure energy is changed to generate a pressure wave to break up the colorant aggregate particles. Let

(4) When the pre-dispersion liquid having a large kinetic energy collides with the screen or other wall, the agglomerated particles of the colorant which have received the collision force are crushed, and the colorant fine particles having a sharp particle size distribution. Becomes

(5) When the dispersion liquid having velocity energy passes through the slit portion of the screen, it becomes a jet flow (jet flow). In the potential core (velocity region not affected by viscous flow) in the jet, the surrounding fluid is sucked at a high velocity. Agglomerated particles of the colorant that have received this energy are crushed to form colorant fine particles having a sharp particle size distribution.

The dispersion time for obtaining the colorant fine particle dispersion is not particularly limited, but is 5 to 30 minutes.
It is preferably 7 to 25 minutes. When circulating, the number of passes is preferably 5 or more, more preferably 5 to 20. If the dispersion time is too long, the dispersion becomes excessive and the abundance of fine particles increases, which is not preferable.

Further, in order to obtain colorant fine particles preferably used in the toner of the present invention, a dispersion container equipped with a stirrer equipped with a screen and a rotor is used, and the dispersion medium is contained in an aqueous medium. Alternatively, a batch-type dispersion treatment in which a colorant (an aqueous medium containing the colorant) is jetted from the stirring chamber of the stirring device may be performed.

FIG. 1C is a schematic view showing a dispersion container equipped with such a stirring device (Clearmix),
Distributed processing is performed by such an apparatus. Figure 1 (c)
, 111 is a dispersion container, 112 is a stirrer, 11
Reference numeral 3 is a stirring shaft for driving the stirring device 112. The stirring device 112 has the same structure (screen and rotor) as that shown in FIG.

Predispersion (dispersion of aggregated particles of colorant)
Is a strong shearing force generated between the rotor and the screen, which enters the stirring chamber from the upper part of the stirring device 112 and rotates at high speed,
Stirred by impact force and turbulence, the weight average particle size is 3
Colorant fine particles of 0 to 300 nm are formed and jetted into the dispersion container 111 from the slit of the screen. In the step of dispersing the colorant fine particles, the dispersion container 111 may have a jacket structure, and hot water or steam, and if necessary, cold water may be flown into the jacket to control the temperature inside the dispersion container 111.

In the case of carrying out the dispersion treatment using the dispersion container shown in FIG. 1 (c), the spouting direction of the colorant from the stirring chamber of the stirrer 112 (spouting direction of the colorant fine particles into the aqueous medium). Is preferably in the downward or horizontal direction. By jetting the colorant (colorant fine particles) in the downward or horizontal direction, the aqueous medium in the dispersion container 111 flows as indicated by the arrow F. As a result, the colorant is jetted downward and its flow is along the wall. It rises and then circulates again into the clear mix. Therefore, the dispersion process can be reliably repeated, and the dispersion energy can be uniformly applied. As a result, it is presumed that the dispersion diameter of the colorant can be made uniform. This makes it possible to efficiently form fine colorant particles having a sharp particle size distribution.

As described above, the colorant particles preferably used in the present invention are crushed by the action of the shearing force generated by the screen and the rotor, and the colorant aggregate particles are crushed to obtain a suitable average particle size (weight average particle size). : 30 to 500 nm) and sharp particle size distribution (standard deviation (σ) is 30 or less)
A dispersion liquid of colorant fine particles (fine particles close to primary particles) having is obtained. By subjecting such colorant fine particles (dispersed particles) to salting out / fusing with resin fine particles, inside of toner particles formed The colorant fine particles are surely introduced into the toner, the introduced colorant particles are not released, and the content ratio of the colorant does not vary among the toner particles.

As a result, even when the toner of the present invention is subjected to image formation under high temperature and high humidity or after the apparatus has been used for a long period of time, image defects such as fog and fine dot dust due to fluctuations in the toner charge amount are observed. It does not occur. Further, in the present invention, since the colorant fine particles are dispersed in the toner particles without using the medium, image defects caused by remaining fine impurities such as crushed pieces of the medium in the toner do not occur.

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 the surfactant is dissolved at a concentration equal to or higher than the critical micelle concentration (CMC).

The disperser used for the dispersion treatment of the colorant particles is not particularly limited, but preferably a stirring device "CLEARMIX (CLEAR) equipped with a rotor rotating at high speed.
MIX) ”(manufactured by M Technique Co., Ltd.), ultrasonic disperser, mechanical homogenizer, manton-goulin, pressure homogenizer such as pressure homogenizer, and medium type disperser such as Getzman mill and diamond fine mill.

In order to salt out / fuse the composite resin particles and the colorant particles, the salting out agent (aggregating agent) having a critical coagulation concentration or more is added to the dispersion liquid in which the composite resin particles and the colorant particles are dispersed. ) Is added and the dispersion is heated to the glass transition temperature (Tg) or higher of the composite resin particles.

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

In the present invention, 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), and then the toner particles are water-based. When separated from the medium, it is preferably carried out at a temperature not lower than the Kraft point of the surfactant present in the aqueous medium, and more preferably at a temperature range of Kraft point to (Craft point + 20 ° C.). is there.

The Kraft point is the temperature at which the aqueous solution containing the surfactant begins to turn cloudy, and the Kraft point is measured as follows.

<Measurement of Kraft Point> An aqueous medium used in the salting-out, aggregating, and fusion-bonding steps, that is, a surfactant solution, was mixed with an actually used amount of an aggregating agent to prepare a solution. Stored for 5 days. The solution was then heated slowly with stirring until it became transparent. The temperature at which the solution became clear is defined as the Kraft point.

In the present invention, the following conventionally known colorants may be used in combination. Examples of conventionally known colorants include various inorganic pigments, organic pigments, and dyes. As the inorganic pigment, conventionally known ones can be used. Specific inorganic pigments are exemplified below.

Examples of black pigments include furnace black, channel black, acetylene black,
Carbon black such as thermal black and lamp black, and magnetic powder such as magnetite and ferrite are also used.

These inorganic pigments can be used alone or in combination of two or more as desired. Further, the amount of the pigment added is 2 to 20% by mass, preferably 3 to 15% by mass, based on the polymer.

When used as a magnetic toner, the above-mentioned magnetite can be added. In this case, from the viewpoint of imparting a predetermined magnetic characteristic, 20 to 6 is contained in the toner.
It is preferable to add 0% by mass.

Known organic pigments and dyes can be used, and specific organic pigments and dyes are exemplified below.

As the magenta or red pigment,
For example, C.I. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I.
Pigment Red 6, C.I. I. Pigment Red 7,
C. I. Pigment Red 15, C.I. I. Pigment Red 16, C.I. I. Pigment Red 48: 1, C.I.
I. Pigment Red 53: 1, C.I. I. Pigment Red 57: 1, C.I. I. Pigment Red 122, C.I.
I. Pigment Red 123, C.I. I. Pigment Red 139, C.I. I. Pigment Red 144, C.I. I.
Pigment Red 149, C.I. I. Pigment Red 1
66, C.I. I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 222
Etc.

Examples of pigments for orange or yellow include C.I. I. Pigment Orange 31, C.I.
I. Pigment Orange 43, C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 13, C.I. I.
Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 9
4, C.I. I. Pigment Yellow 138, C.I. I. Pigment Yellow 180, C.I. I. Pigment Yellow 1
85, C.I. I. Pigment Yellow 155, C.I. I. Pigment Yellow 156 and the like.

As the pigment for green or cyan,
For example, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 1
5: 3, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 60, C.I. I. Pigment Green 7 and the like.

Examples of dyes include C.I. I. Solvent Red 1, 49, 52, 58, 63,
111, 122, C.I. I. Solvent yellow 1
9, the same 44, the same 77, the same 79, the same 81, the same 82, the same 9
3, ibid 98, ibid 103, ibid 104, ibid 112, ibid 16
2, C.I. I. Solvent Blue 25, 36, 60,
No. 70, No. 93, No. 95 and the like can be used, and a mixture thereof can also be used.

These organic pigments and dyes can be used alone or in combination of two or more as desired.
The amount of pigment added is 2 to 20% by mass based on the polymer.
And preferably 3 to 15% by mass.

The colorant (colorant particles) constituting the toner of the present invention may be surface-modified. As the surface modifier, conventionally known ones can be used, and specifically, a silane coupling agent, a titanium coupling agent, an aluminum coupling agent and the like can be preferably used. Examples of the silane coupling agent include alkoxysilanes such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane and diphenyldimethoxysilane, siloxanes such as hexamethyldisiloxane, γ-chloropropyltrimethoxysilane and vinyltrisilane. Chlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,
γ-ureidopropyltriethoxysilane and the like can be mentioned. As the titanium coupling agent, for example, TTS, 9S, 38S, 41B, 46B, 55, 138, which is commercially available under the trade name "Planeact" manufactured by Ajinomoto Co., Inc.
Commercial products A-1, B- manufactured by Nippon Soda Co., Ltd. such as S, 238S.
1, TOT, TST, TAA, TAT, TLA, TO
G, TBSTA, A-10, TBT, B-2, B-4,
B-7, B-10, TBSTA-400, TTS, TO
A-30, TSDMA, TTAB, TTOP and the like can be mentioned. As the aluminum coupling agent, for example,
Examples include "Planeact AL-M" manufactured by Ajinomoto Co., Inc.

The amount of these surface modifiers added is preferably 0.01 to 20% by mass, more preferably 0.1 to 5% by mass, based on the colorant. In addition, as a method for modifying the surface of the colorant particles, a method of adding a surface modifier to the dispersion liquid of the colorant particles and heating the system to react them can be mentioned. Colorant particles surface-modified in this way,
It is obtained by collecting by filtration, repeating washing treatment with the same solvent and filtration treatment, and then drying treatment.

The electrostatic image developing toner of the present invention will be described. The toner particles constituting the toner for developing an electrostatic image of the present invention have a volume average particle diameter of 3.0 μm to 7.5 μ.
m is necessary, but preferably 3.5 μm
To 7.0 μm, and more preferably 4.0 μm
It is 6.5 μm.

The particle size of the toner particles can be controlled by adjusting the concentration of the aggregating agent (salting out agent), the amount of the organic solvent added, the fusing time, and the composition of the polymer during the production of the toner.

Here, the volume average particle diameter of the toner particles is measured by Coulter Counter TA-II, Coulter Multisizer (both manufactured by Coulter, Inc.), SLAD110.
0 (a laser diffraction particle size measuring device manufactured by Shimadzu Corporation) can be used for measurement.

The toner particles according to the present invention have a circularity of 0.9.
It is necessary to be 45 to 0.985, but it is preferably 0.950 to 0.980. The circularity is 0.
When it is less than 945, the distribution of the amount of charge is widened and the sharpness of the image is deteriorated. When it is more than 0.985, the adhesive force between particles is too high, which causes filming of the photoconductor.

Here, the circularity is defined by the following equation,
It measured using FPIA-2000 (made by Sysmec).

Circularity = (perimeter of equivalent circle) / (perimeter of particle projection image) = (perimeter of equivalent circle) / (perimeter) = (2π × (sum of areas / π) ^{(1/2 )} ) / (Peripheral length) The toner for developing an electrostatic charge image of the present invention preferably contains two kinds of surfactants. The surfactants are used in the step of forming toner particles, and the colorant dispersion and Although it was used for remarkably improving the dispersion stability of the colorant particles in the toner, the effect described in the present invention can be more preferably obtained even after the toner particles are formed.

It is particularly preferable that the surfactant used in the resin particle dispersion liquid and the surfactant used in the colorant dispersion liquid are different from each other and are contained in the toner particles. . Here, 2 included in the toner
The content ratio of the seed surfactant is preferably adjusted to be in the range of 10: 1 to 1:10.

As two kinds of surfactants, alkyl sulfates such as sodium dodecyl sulfate are preferably used, and as another kind, ethylene oxide adducts of alkyl sulfates such as sodium dodecyl sulfate are preferably used.

Here, as the alkyl sulfate ester and the ethylene oxide adduct of the alkyl sulfate ester which are preferably used as the two kinds of surfactants, compounds represented by the following general formula (a) or general formula (b) are given. It is preferably used.

General Formula (a) R ₁ (OR ₂ ) _n OSO ₃ M In the formula, R ₁ is an alkyl group or arylalkyl group having 6 to 22 carbon atoms, and R ₂ is an alkylene group having 2 to 6 carbon atoms. Represents n represents an integer of 1 to 11, and M represents a monovalent metal element or ammonium ion.

General formula (b) R ₁ (OR ₂ ) _n SO ₃ M In the formula, R ₁ represents an alkyl group having 6 to 22 carbon atoms or an arylalkyl group, and R ₂ represents an alkylene group having 2 to 6 carbon atoms. And n represents an integer of 1 to 11. M represents a monovalent metal element or ammonium ion.

The surfactants represented by the general formulas (a) and (b) will be described. General formula (a), (b)
In the formula, R ₁ represents an alkyl group having 6 to 22 carbon atoms or an arylalkyl group, and preferably 8 to 20 carbon atoms.
Is an alkyl group or an arylalkyl group, more preferably an alkyl group having 9 to 16 carbon atoms or an arylalkyl group.

Examples of the alkyl group having 6 to 22 carbon atoms represented by R ₁ include n-hexyl group, n-heptyl group, n-octyl group, n-decyl group, n-undecyl group and n-hexadecyl group. Group, cyclopropyl group, cyclopentyl group, cyclohexyl group and the like.

The arylalkyl group represented by R ₁ includes a benzyl group, a diphenylmethyl group, a cinnamyl group,
Examples thereof include a styryl group, a trityl group and a phenethyl group.

In the general formulas (a) and (b), R ₂ represents an alkylene group having 2 to 6 carbon atoms, preferably an alkylene group having 2 to 3 carbon atoms.

Examples of the alkylene group having 2 to 6 carbon atoms represented by R ₂ include ethylene group, trimethylene group, tetramethylene group, propylene group and ethylethylene group.

In the general formulas (a) and (b), n is 1 to
Although it is an integer of 11, it is preferably 2 to 10, more preferably 2 to 5, and particularly preferably 2 to 3.

In the general formulas (a) and (b), examples of the monovalent metal element represented by M include sodium, potassium and lithium. Among them, sodium is preferably used.

Specific examples of the surfactants represented by the general formulas (a) and (b) are shown below, but the invention is not limited thereto.

Compound (101): C ₁₀ H ₂₁ (OCH ₂ C
H _{2) 2} OSO ₃ Na Compound _{(102): C 10 H 21} (OCH 2 CH 2) 3 OSO 3
Na compound _{(103): C 10 H 21} (OCH 2 CH 2) 2 SO 3 N
a Compound (104): C ₁₀ H ₂₁ (OCH ₂ CH ₂ ) ₃ SO ₃ N
a Compound (105): C ₈ H ₁₇ (OCH ₂ CH (CH ₃ )) ₂
OSO ₃ Na compound (106): C ₁₈ H ₃₇ (OCH ₂ CH ₂ ) ₂ OSO ₃
In the present invention, from the viewpoint of keeping the charge retention function of the toner in a good state, suppressing fog generation under high temperature and high quality, and improving transferability, and suppressing increase in charge amount under low temperature and low humidity,
From the viewpoint of stabilizing the development amount, the content of the surfactant represented by the general formulas (a) and (b) in the toner for developing an electrostatic image of the present invention is 1 ppm to 10 ppm.
00 ppm is preferred, more preferably 5 ppm to 50
0 ppm, particularly preferably 7 ppm to 100 pp
m.

By incorporating a surfactant into the toner in an amount within the above range, the electrostatic property of the toner for developing an electrostatic charge image of the present invention is not influenced by the environment and is always uniformly and stably applied. , Can be maintained.

The method for measuring the content of the surfactant represented by the above general formulas (a) and (b) in the toner for developing an electrostatic image of the present invention is as follows.

1 g of the toner was dissolved in 50 ml of chloroform, and the surfactant was extracted from the chloroform layer with 100 ml of ion-exchanged water.
Extracted again with the ion-exchanged water described above, diluted a total of 200 ml of the extract (aqueous layer) to 500 ml, and used this diluted solution as a test solution to develop color with methylene blue according to the method specified in JIS 33636, measure the absorbance, and prepare separately. The content in the toner was measured from the obtained calibration curve.

The boundaries represented by the general formulas (a) and (b) are
The structure of the surfactant is ¹Using H-NMR
Then, the structure was determined.

The toner particles according to the present invention have a sea-island structure, and the sea-island structure means a structure in which isolated island-like phases are present in the continuous phase. That is, in the toner of the present invention, the respective components of the resin and the colorant forming the toner particles do not mix with each other, but independently form a phase, so that the toner particles have a sea-island structure. .
Further, in the present invention, due to the nature of the toner, the island of the colorant is present in the continuous phase (sea) of the resin.

The toner particles according to the present invention have a sea-island structure. That is, the cross-sectional photograph taken by a transmission electron microscope shows that the toner particles have a brightness in the sea area and the island area. It is confirmed by being shown with different areas of. That is, it is confirmed by the transmission electron microscope that the toner particles according to the present invention have granular islands (colorant phase) of different brightness in the continuous phase (binder resin phase). Further, from the observation result of the electron microscope, the factors that specify the sea-island structure in the toner particles such as the number of islands in one toner particle and the shape factor of the island can be obtained as numerical values.

Luminance in a transmission electron microscope is caused by visualizing a difference in electron beam transmissivity caused by each element constituting toner particles, that is, a binder resin and a colorant, and is generally used. Since the colorant has a lower electron beam transmittance than the binder resin, it is photographed at low brightness.

In the electron micrograph, low brightness means 0 when the brightness signal of a pixel is divided into 256 gradations.
~ 99 gradations, and medium brightness is 80 ~ 160
The one in the range of gradation and the one having high brightness mean the one in 127 to 255 gradations, but in the present invention, relative ones, that is, the constituents of the toner described above may be discriminated from each other by the photograph, and are not necessarily colored. It is not essential that the brightness of the agent is within the low brightness range defined in the above range.

As described above, in the present invention, by identifying each constituent element in the toner particles based on the brightness,
The sea is the sea, and the islands are islands that can be visually identified and identified by electron micrographs. An image that can be visually identified by the image analysis device installed in the electron microscope device. It is converted into information.

FIGS. 2A and 2B are schematic views showing an example of the toner particles having the sea-island structure of the present invention. In the electron micrograph, the toner particles of the present invention are the schematic views. It is confirmed that it is composed of a continuous phase and islands, as shown in. It is also confirmed that there is a region having no island portion of length a and depth b along the outer periphery of the toner particle.

Further, in FIG. 2, it was confirmed that, as the islands in the toner particles, the binder resin which is a constituent element of the toner also forms an island structure in the continuous phase in addition to the islands of the colorant. It

The transmission electron microscope apparatus according to the present invention capable of observing the structure of toner particles is usually well observed by a model well known to those skilled in the art, and for example, "LEM-".
Model 2000 (manufactured by Topcon) "or the like is used. In the present invention, the value obtained from the result of the transmission electron micrograph of the number of islands in the toner particles, which is the feature of the present invention, is calculated from the projection surface of 1,000 or more toner particles at a magnification of 10,000. It is calculated.

In the present invention, the photographing method using a transmission electron microscope is a commonly known method used for measuring toner particles. That is, as a specific method for measuring the tomographic plane of the toner, the toner may be sufficiently dispersed in a room temperature curable epoxy resin and then embedded and cured, or dispersed in styrene fine powder having a particle diameter of about 100 nm. After applying pressure, the resulting block was dyed with ruthenium tetroxide or osmium tetroxide in combination and cut into flakes using a microtome equipped with diamond teeth. The tomographic morphology of the toner was photographed using a scanning electron microscope (TEM). The shape of the region of the colorant in the toner particles is visually confirmed from the photograph, and the image information photographed by the image processing device "Luzex F" (manufactured by Nireco Corp.) provided in the electron microscope device. Is calculated, the characteristics of the island portion in the toner particles can be obtained.

The structure of the toner particles according to the present invention is specified by the above method. Hereinafter, the factors that specify the structure of the toner particles according to the present invention will be described in detail.

The island of the colorant component present in the toner particles according to the present invention is shown as island B in the schematic view of FIG. As is clear from this schematic diagram, in the toner particles having the sea-island structure of the present invention, islands of other toner constituent elements may be present in addition to the islands of the colorant component. Since the other islands and the other islands have different brightness, they can be easily identified in the electron micrograph. The island of the colorant component in the toner particles according to the present invention is specified based on the area of the Voronoi polygon described below.

The numerical value for specifying the island portion in the sea-island structure in the toner particles according to the present invention is calculated by the image analysis apparatus attached to the electron microscope apparatus based on the image information observed by the electron microscope apparatus.

The area of the Voronoi polygon used in the present invention indicates the occupancy of the island portion in the toner particles. Voronoi polygon or Voronoi polyhedron is
For example, as published in Iwanami Physics and Chemistry, by creating vertical bisectors or vertical bisectors of adjacent points when many points are dispersed in space or on a plane. The entire space is divided into polyhedra, or the entire plane is divided into polygons, the polyhedrons formed in this way are called Voronoi polyhedra, the polygons are called Voronoi polygons, and such division of spaces or planes is called Voronoi division. . FIG. 3 shows an example of toner particles according to the present invention divided by Voronoi polygons.

As described above, in the present invention, the area occupied by the islands in the sea-island structure of the toner particles is represented by the Voronoi polygonal area obtained by Voronoi division as a measure of the ratio of the islands in the toner particles. It is a thing. That is, in the present invention, focusing on the center of gravity of the islands present in the toner particles, a polygon is formed by the perpendicular bisectors formed by connecting the centers of gravity of adjacent islands, and the area of these polygons is transmitted through It is calculated by the image analysis device installed in the electron microscope device based on the result of the photograph taken by the scanning electron microscope.

A Voronoi polygon having a large area means
This indicates that the centers of gravity of adjacent islands are far apart from each other, that is, the islands in the particles are sparsely occupied. Also, a small Voronoi polygon area means that the distance between the centers of gravity of adjacent islands is short and close to each other, that is, the islands in the particles are densely occupied. It is a thing. In the present invention, the Voronoi polygon of the island portion in the toner particles is measured for 1000 toners, and the average value per toner particle is calculated.

When the Voronoi polygon is generally defined mathematically, it is 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 || X-P (i) | <| X-P (j) |
for all i to j}, where X and P are position vectors, and || indicates a distance in Euclidean space.

It is assumed that V (i) thus defined forms a Voronoi polygon at R2 and a Voronoi polyhedron at R3. When V (i) and V (j) are adjacent to each other, the boundary of the Voronoi polygon is Is defined as a part of the perpendicular bisector of the line segment connecting the point P (i) and the point P (j). The Euclidean space is as defined and described in mathematical science dictionaries and the like.

The center of gravity of the toner particles and the center of gravity of each island in the toner particles according to 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. To be done. Here, the barycentric coordinates of the toner particles are obtained by calculating the product of the luminance value of the minute area at any point of the toner particles and the coordinate value of that arbitrary point. Then, for all coordinates existing in the entire toner particle, the product of the brightness and the coordinate value is obtained, and the sum of the products is calculated as the brightness of the toner particle (the total brightness value at each coordinate point obtained as described above). It is obtained by removing. Similarly, regarding the center of gravity of the island, the center of gravity of the island is also calculated by obtaining the luminance at any coordinate point in the island. As described above, the barycentric coordinates of the toner particles and the barycentric coordinates of each island existing in the toner particles according to the present invention are calculated based on the brightness at each arbitrary point, that is, from the lightness and darkness of the image.

In the present invention, the average area of Voronoi polygons formed by the perpendicular bisectors between the centers of gravity of adjacent islands in the toner particles is 20,000 to 120,000 nm.
2 and the coefficient of variation of the average value of the area is 25% or less. In the present invention, the coefficient of variation of the area of the Voronoi polygon is calculated by the following formula.

Variation coefficient of area of Voronoi polygon = {S1
/ K1} × 100 (%) In the formula, S1 represents the standard deviation of the area of the Voronoi polygon of the island portion existing in the toner particles, and K1 represents the average value of the area of the Voronoi polygon.

The average value of the Voronoi polygonal areas of adjacent islands in the toner particles according to the present invention is more preferably 40,000 nm ^{2 to} 100,000 nm ^2.
And the coefficient of variation is 20% or less.

Further, in the toner particles according to the present invention, the average value of the Voronoi polygon areas of adjacent islands in the toner particles is 20,000 nm ^{2 to} 120,000 nm ² and 160,000 nm ² or more. The islands that form the Voronoi polygon with the area of
From the viewpoint of making the charge amount distribution uniform, the islands forming Voronoi polygons having an area of preferably 50,000 nm 2 or less are present in one toner particle. The total content is 30% by number or more, and more preferably 60% by number or more.

The average area of Voronoi polygons formed by the perpendicular bisectors between the centers of gravity of adjacent islands in the toner particles according to the present invention is 20,000 to 120,000 nm.
Within the range of 2, however, those outside this range have an unfavorable occupancy condition of the island portion in the toner particle. For example, the colorant existing as an island in the particle has an effect on the toner particle. It is not preferable because it is difficult to find the effect of the present invention.

The coefficient of variation of the average value of the area of the Voronoi polygons formed by the adjacent islands in the toner particles according to the present invention is used to specify the variation in the area of the Voronoi polygons, that is, in the toner particles. It is intended to specify the variation in the occupied state of the island portion, and the coefficient of variation of the average value of the area of the Voronoi polygon may be within the range of 25% or less, preferably 20% or less. It should be noted that when the coefficient of variation is 0%, that is, the average value of the area of the Voronoi polygon does not vary, in other words, the occupation state of islands in the toner particles does not vary at all. There is no need for the occupancy to be the same.

In the present invention, the number of islands in which the area of the Voronoi polygon is 160,000 nm ² or more is 3 to 20% of the total number of islands present in one toner particle.
This means that the islands are appropriately dispersed in the toner particles, and the islands are appropriately distributed in this way, and thus the islands are unevenly distributed in the toner particles. Means that the colorant is effectively added to the toner particles.

Further, in the present invention, the area of the Voronoi polygon formed by the islands existing within the specific range from the center of gravity of the toner particles is larger than the area of the Voronoi polygon formed by the islands existing outside the range. It is preferably 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 the average value of the area of the Voronoi polygon formed by the islands existing within the radius of 1000 nm. It is preferable that the particle size is larger than that, which means that in the toner particles, the dispersed state of the islands is sparse at a position apart from the center of gravity of the toner particles to some extent. 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 is found.

Further, in the toner of the present invention, it is preferable that the toner particles have a sea-island structure, but the toner particles have a region where no island exists in the region along the outer periphery of the toner particle. In the schematic diagrams of FIGS. 2A and 2B, the region indicated by the length a and the depth b along the outer periphery of the toner particle cross section is a region that does not include islands. That is, it was confirmed that the toner of the present invention has a region that does not include any island portion along the outer periphery of the toner particle cross section, and the region has a depth of 100 nm to 200 nm, and a more preferable depth is 120 n.
m-180 nm, length 500 nm-6000 nm,
A more preferable length is 800 nm to 4000 nm.

In the toner of the present invention, the charge retention performance is improved and the scattering of light near the surface of the toner is prevented by preventing the island from existing in the specific region along the outer periphery of the toner particle. Presumed to be out. Further, it is presumed that the effect found in the present invention is promoted by optimally dispersing the colorant added to the toner particles in the particles. A toner having no colorant-free region along the outer periphery of the toner particle cross section as in the present invention deteriorates the charge retention performance of the toner particle, and it is difficult to reproduce the effect found in the present invention. become.

Further, the sea part of the toner particles having a sea-island structure of the present invention is preferably made of resin.
In the toner particles having a sea-island structure, islands of other toner constituent elements may be present in addition to islands of the colorant component. The island is mentioned, and the crystalline substance is an organic compound having a melting point, preferably a hydrocarbon compound containing an ester group in its compound structure. The melting point of the crystalline substance in the toner particles according to the present invention is lower than the softening point of the toner, specifically, 130 ° C. or lower. The organic compound preferably has an ester group in its structure, and also includes a crystalline polyester compound.

As a method for confirming the melting point of the crystalline substance forming the island portion, one confirmed by DSC is as follows:
It is confirmed by a means such as an X-ray diffractometer that it has crystallinity. Further, the crystalline substance contained in the toner of the present invention also contains a substance which exhibits a function as a release agent during image formation.

[0166] The melting point of the crystalline substance is 50 to 130 ° C.
Is preferable, and more preferably 60 to 120 ° C.
It is said that In a toner containing a crystalline substance having a melting point in the range of 50 to 130 ° C., it is possible to lower the melt viscosity, improve the adhesiveness to paper and the like, and moreover, the crystalline substance is present. Even so, the elastic modulus on the high temperature side is maintained in a preferable range, and good offset resistance is exhibited.

When the melting point of the crystalline substance is less than 50 ° C., the fixability itself is improved, but the storability is deteriorated, causing a problem in practical use. On the other hand, when the melting point is higher than 130 ° C., the melting start temperature becomes high, so that the contribution to the improvement of the fixability is low and the effect of improving the fixability is reduced.

Here, the melting point of the crystalline substance means a value measured by a differential calorimeter (DSC), and specifically,
The temperature showing the maximum endothermic peak measured when the temperature is raised from 0 ° C. to 200 ° C. under the condition of 10 ° C./min (first heating process) is defined as the melting point. And, this melting point is the endothermic peak (P
1) ”.

Specific examples of the melting point measuring device include DSC-7 manufactured by Perkin Elmer.
A specific method for measuring the melting point by a differential calorimeter (DSC) is as follows: As temperature rising / cooling conditions, the temperature is left at 0 ° C. for 1 minute, and then the temperature is raised to 200 ° C. at 10 ° C./min.
The temperature showing the maximum endothermic peak measured at that time is defined as the endothermic peak P1 in the first temperature rising process. After that, 200 ℃
After being left for 1 minute at 10 ° C./min, the temperature is lowered, and the temperature showing the maximum exothermic peak measured at that time is taken as the exothermic peak P2 in the first cooling process.

The crystalline substance used in the toner of the present invention has an endothermic peak (P1) in the first temperature rising process by DSC.
Is preferably present at 50 to 130 ° C, particularly 60 to 120 ° C. Further, the exothermic peak (P2) in the first cooling process by DSC is 30 to 110 ° C, particularly 40 to 120 ° C.
Is preferably present. Here, the endothermic peak (P
The relationship of P1 ≧ P2 is established between 1) and the exothermic peak (P2). The temperature difference (P1-P2) is not particularly limited, but is preferably 50 ° C or less.

By including the crystalline substance having the above-mentioned thermal characteristics, it is possible to exhibit an excellent offset preventing effect (wide fixing temperature range) and an excellent fixing property (high fixing ratio). In order to exert the effect of the present invention, it is preferable that the binder resin and the crystalline substance exist in a state of being phase-separated from each other.

That is, the crystalline substance dissolves sharply, and as a result, the melt viscosity of the entire toner can be lowered and the fixability can be improved. Also,
By being phase-separated from each other, it is possible to suppress the decrease in elastic modulus on the high temperature side, and therefore the offset resistance is not impaired.

Next, the shape of the toner of the present invention will be described in detail. As the toner particles used in the present invention, it is preferable to use a toner composed of toner particles having a shape coefficient variation coefficient of 16% or less and a number variation coefficient of number particle size distribution of 27% or less. By using the toner as described above, the state of existence of the external additive on the toner surface becomes more uniform, the charge amount distribution becomes sharp, and high fluidity can be obtained. As a result, excellent developability and fine line reproducibility, and stable cleaning property can be formed for a long period of time.

In addition, when the electric charge is applied to the toner particles by frictional charging, it is presumed that the external additive is likely to be buried particularly at the corners, and the toner particles are likely to be unevenly charged. That is, the ratio of toner particles having no corners is set to 50 number% or more, and the number variation coefficient in the number particle size distribution is 27
By using a toner composed of toner particles controlled to be less than 100%, excellent developability and fine line reproducibility,
It has been found that a high quality image can be formed for a long period of time.

Further, it was found that even when the toner has a specific shape and the shapes are made uniform, the external additive is not buried and the charge amount distribution becomes sharp. That is, the proportion of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more, and the variation coefficient of the shape factor is 16%.
It has been found that even by using the following toner, it is possible to form a high-quality image excellent in developability and fine line reproducibility for a long period of time.

Now, 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 of the present invention are measured by Coulter Counter TA-II or Coulter Multisizer (manufactured by Coulter Co.). In the present invention, a Coulter Multisizer was used, and an interface (manufactured by Nikkaki Co., Ltd.) for outputting the particle size distribution and a personal computer were connected and used. The aperture used in the Coulter Multisizer is 100
The particle diameter distribution and average particle diameter were calculated by measuring the volume diameter and number diameter of 2 μm or more using a particle diameter of μm. 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 represents the cumulative 50% diameter in the number particle size distribution, that is, Dn50.

The number variation coefficient in the number particle size distribution of toner is calculated from the following formula. Number variation coefficient = [S / Dn] × 100 (%) [In the formula, S represents the standard deviation in the number particle size distribution, and D
n indicates a number average particle diameter (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 voids in the transferred toner layer are reduced, the fixability is further improved, and offset is less likely to occur. Further, the charge amount distribution becomes sharp, the transfer efficiency is increased, and the image quality is improved.

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, but classification in a liquid is effective for reducing the number variation coefficient. As a method of classifying in this liquid, there is a method of controlling the number of revolutions and separately collecting and adjusting the toner particles according to the difference in the sedimentation speed caused by the difference in the diameter of the toner particles by using a centrifuge.

Next, the shape factor of the toner of the present invention will be described. The toner of the present invention has a shape factor of 1.2 to 1.
The ratio of toner particles in the range of 6 is 65 number% or more, the variation coefficient of the shape factor is 16% or less, and the number variation coefficient in the number particle size distribution is 27% or less. Here, the shape factor of the toner of the present invention is represented by the following formula, and indicates the degree of roundness of toner particles.

Shape factor = ((maximum diameter / 2) ² × π) / projected area Here, the maximum diameter means the parallel line when a projected image of toner particles on a plane is sandwiched by two parallel lines. Refers to the width of the particles at which the interval is maximum. The projected area means the area of the projected image of the toner particles on the plane. In the present invention, this shape factor is obtained by taking a photograph of the toner particles magnified 2000 times with a scanning electron microscope, and then based on the photograph, "SCANNING IMAGE ANALYZE
R ”(manufactured by JEOL Ltd.) was used to measure the photographic image. At this time, the shape factor of the present invention was measured by the above calculation formula using 100 toner particles.

Next, the non-cornered toner particles preferably used in the present invention will be described. Here, the toner particles having no corners are toner particles that do not substantially have projections where electric charges are concentrated or projections that are easily worn by stress, that is, as shown in FIG. , Toner particles T
When the major axis of L is L, a circle C of radius (L / 10)
When the inside of the toner particle T is in contact with the peripheral line of the toner particle T at one point and is rolled inside, the case where the circle C does not substantially protrude to the outside of the toner T is called “toner particle having no corner”.
The term “when substantially not protruding” means a case where there is one or less protrusions with protruding circles.

The "major axis of the toner particles" means the width of the particles such that when the projected image of the toner particles on the plane is sandwiched by two parallel lines, the distance between the parallel lines becomes maximum. 4B and 4C are schematic diagrams showing projected images of toner particles having corners, respectively.

The toner having no corners was measured as follows. First, an enlarged photograph of toner particles is taken with a scanning electron microscope and further enlarged to obtain a photographic image at 15,000 times magnification. Then, the presence or absence of the above-mentioned corner is measured for this photographic image. This measurement was performed on 1000 toner particles.

In the toner of the present invention, the proportion of toner particles having no corners is 50% by number or more, preferably 70% by number or more. When the ratio of the toner particles having no corners is 50% by number or more, the generation of fine particles is less likely to occur due to the stress with the developer transport member and the like,
So-called contamination of the surface of the developer transport member can be suppressed, the charge amount distribution becomes sharp, the chargeability is stable, and good image quality can be formed for a long period of time.

The method for obtaining the toner without corners is not particularly limited. For example, as described above as a method of controlling the shape factor, a method of spraying toner particles in a hot air flow, a method of repeatedly applying mechanical energy due to impact force in a gas phase, or a method of dissolving toner It can be obtained by adding it to a solvent that does not contain it and imparting a swirling flow.

In the toner of the present invention, when the particle diameter of the toner particles is D (μm), the natural logarithm lnD is plotted on the abscissa, and this abscissa is divided into a plurality of classes at intervals of 0.23. In the histogram showing the standard particle size distribution, the sum of the relative frequency (m1) of toner particles included in the most frequent class and the relative frequency (m2) of toner particles included in the next most frequent class. It is preferable that the toner (M) is 70% or more.

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 becomes narrow, so that the toner is used in the image forming process. As a result, the occurrence of selective development can be reliably suppressed.

In the present invention, the histogram showing the number-based particle size distribution has a natural logarithm lnD (D: particle size of each toner particle) at a plurality of grades (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:
1.84-2.07: 2.07-2.30: 2.30-
2.53: 2.53 to 2.76 ...), which is a histogram showing a number-based particle size distribution, and the histogram shows 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 is created by the particle size distribution analysis program in the computer.

[Measurement conditions] 1: Aperture: 100 μm 2: Sample preparation method: Electrolyte solution [ISOTON II (manufactured by Coulter Scientific Japan)] 50-1
A suitable 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 an ultrasonic disperser for 1 minute.

The method for producing the toner of the present invention will be described. The toner of the present invention is obtained by polymerizing at least a polymerizable monomer in an aqueous medium, and this production method is to prepare resin particles by polymerizing the polymerizable monomer by a suspension polymerization method. Alternatively, emulsion polymerization or miniemulsion polymerization of the monomer is performed in a liquid (in an aqueous medium) containing an emulsion of the necessary additives to prepare fine resin particles, and charge as necessary. After the controllable resin particles are added, an organic solvent, an aggregating agent such as salts, and the like are added to coagulate and fuse the resin particles.

<Suspension Polymerization Method> As an example of the method for producing the toner of the present invention, a charge control resin is dissolved in a polymerizable monomer, and a colorant and, if necessary, a release agent, and further polymerization are used. Various constituent materials such as an initiator are added, and the various constituent materials are dissolved or dispersed in the polymerizable monomer using a homogenizer, a sand mill, a sand grinder, an ultrasonic disperser or the like.
The polymerizable monomer in which these various constituent materials are dissolved or dispersed is dispersed in an oil droplet having a desired size as a toner in a water-based medium containing a dispersion stabilizer by using a homomixer or a homogenizer. After that, the stirring mechanism is moved to a reaction device (stirring device) which is a stirring blade described later, and the polymerization reaction is advanced by heating. After completion of the reaction, the dispersion stabilizer is removed, filtered, washed, and dried to prepare the toner of the present invention. The “aqueous medium” as referred to in the present invention means one containing at least 50% by mass of water.

<< Emulsion Polymerization Method >> As a method for producing the toner of the present invention, there may be mentioned a method in which resin particles are salted out / fused in an aqueous medium. This method is not particularly limited, but for example, the methods described in JP-A-5-265252, JP-A-6-329947, and JP-A-9-15904 can be mentioned. That is, a method of salting out, aggregating, and fusing a plurality of fine particles composed of resin particles and a constituent material such as a colorant, or fine particles composed of a resin and a colorant, etc., particularly by dispersing them in water using an emulsifier After that, a coagulant having a critical coagulation concentration or more is added for salting out, and at the same time, the particles are gradually grown while forming fused particles by heat fusion at a temperature not lower than the glass transition temperature of the formed polymer itself. When the desired particle size is reached, a large amount of water is added to stop the particle size growth, and the particle surface is smoothed while heating and stirring to control the shape, and the particles are heated in a fluid state while containing water. By drying, the toner of the present invention can be formed. Here, a solvent such as alcohol, which is infinitely soluble in water, may be added together with the coagulant.

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

In the method for producing a toner of the present invention, the composite resin fine particles obtained by the multi-step polymerization method and the colorant particles are salted out / fused, and the multi-step polymerization method will be described below.

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

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

Each step will be described in detail below. [Multistage Polymerization Step] The multistage polymerization step is a polymerization method carried out in order to expand the molecular weight distribution of the resin particles in order to obtain a toner in which offset generation is prevented. That is, the polymerization reaction is performed in multiple stages in order to form a phase having different molecular weight distributions in one resin particle, and the obtained resin particle has a molecular weight gradient from the center of the particle toward the surface layer. It is intended to be formed. For example, a method of forming a low molecular weight surface layer by first adding a polymerizable monomer and a chain transfer agent after obtaining a high molecular weight resin particle dispersion liquid is adopted.

In the present invention, it is preferable to employ a multi-step polymerization method of three or more steps in view of the stability of production and the crushing strength of the obtained toner. The two-step polymerization method and the three-step polymerization method, which are typical examples of the multi-step polymerization method, will be described below. In the toner obtained by such a multi-step polymerization reaction, a toner having a lower molecular weight on the surface layer is preferable from the viewpoint of crushing strength.

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

To explain this method 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 dispersing oil droplets therein, the system is subjected to a polymerization treatment (first stage polymerization) to prepare a dispersion liquid of high molecular weight resin particles containing a crystalline substance.

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

<Three-Step Polymerization Method> The three-step polymerization method comprises a central portion (nucleus) formed of a high molecular weight resin, an intermediate layer containing a crystalline substance, and an outer layer (shell) formed of a low molecular weight resin. It is a method for producing composite resin particles. The toner of the present invention exists as the composite resin particles as described above.

To explain this method in detail, first, the dispersion liquid of resin particles obtained by the polymerization treatment (first-stage polymerization) according to a conventional method is added to an aqueous medium (for example, an aqueous solution of a surfactant). Along with the addition of the above, in the above aqueous medium, a monomer solution obtained by dissolving a crystalline substance in a monomer is dispersed in oil droplets, and then this system is subjected to a polymerization treatment (second-stage polymerization) to obtain a resin. 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 the dispersion.

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

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 the resin particles (nucleus particles) or the coating layer (intermediate layer) containing the crystalline substance are formed, the crystalline substance is dissolved in the monomer, and the resulting monomer solution is used as an oil in an aqueous medium. In this method, latex particles are obtained by dispersing in drops, adding a polymerization initiator to this system, and subjecting to a polymerization treatment.

The aqueous medium referred to in the present invention means water 50 to 10
A medium composed of 0 mass% and a water-soluble organic solvent of 0 to 50 mass%. As the water-soluble organic solvent, for example, methanol, ethanol, isopropanol, butanol,
Acetone, methyl ethyl ketone, tetrahydrofuran and the like can be exemplified, and an alcohol-based organic solvent that does not dissolve the obtained resin is preferable.

As a suitable polymerization method for forming resin particles or a coating layer containing a crystalline substance, the crystalline substance is dissolved in an aqueous medium in which a surfactant having a concentration below the critical micelle concentration is dissolved. A monomer solution dissolved in a monomer is dispersed into oil droplets using mechanical energy to prepare a dispersion liquid, and a water-soluble polymerization initiator is added to the obtained dispersion liquid to A method of radical polymerization (hereinafter referred to as "mini-emulsion method" in the present invention) can be mentioned, and the effects of the present invention can be exhibited more preferably. In addition,
In the above method, an oil-soluble polymerization initiator may be used instead of the water-soluble polymerization initiator or together with the water-soluble polymerization initiator.

According to the mini-emulsion method of mechanically forming oil droplets, unlike the usual emulsion polymerization method, the crystalline substance dissolved in the oil phase is less desorbed, and the resin particles or the coating layer to be formed are formed. A sufficient amount of crystalline substance can be introduced therein.

[0209] Here, the disperser for dispersing oil droplets by mechanical energy is not particularly limited, and for example, a stirrer "CLEARMIX" (M. -Technique Co., Ltd.), an ultrasonic disperser, a mechanical homogenizer, a Manton Gaulin, a pressure homogenizer, and the like. The dispersed particle size is 1
0 nm to 1000 nm, preferably 50 nm to 1
000 nm, and more preferably 30 nm to 300 nm. 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.

As another polymerization method for forming the resin particles or the coating layer containing the crystalline substance, known methods such as emulsion polymerization method, suspension polymerization method and seed polymerization method can be adopted. . In addition, these polymerization methods can also be adopted to obtain resin particles (core particles) or a coating layer forming the composite resin particles, which does not contain a crystalline substance.

The particle size of the composite resin particles obtained in this polymerization step is 10 n in terms of mass average particle size 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.

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

The toner of the present invention is obtained by forming a resin layer obtained by fusing resin particles by a salting-out / fusing method on the surfaces of the resin and the colored particles, which will be described below. explain.

[Salting-out / fusion-bonding step] In this salting-out / fusion-bonding step, the composite resin particles obtained by the multi-step polymerization step and the colorant particles are salted-out / fusion-bonded (salting-out and fusion-bonding). Is caused at the same time) to obtain amorphous (non-spherical) toner particles.

The term "salting out / fusion" used in the present invention means that salting out (aggregation of particles) and fusion (disappearance of the interface between particles) occur simultaneously, or salting out and fusion occur simultaneously. Refers to an act. In order to perform salting out and fusion at the same time, particles (composite resin particles, colorant particles) are formed under the temperature condition of the glass transition temperature (Tg) of the resin constituting the composite resin particles or higher.
Need to be aggregated.

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

[Aging Step] The aging step is a step subsequent to the salting-out / fusion step, and the temperature is kept near the melting point of the crystalline substance, preferably the melting point ± 20 ° C. after the resin particles are fused, and the temperature is kept constant. In this step, the crystalline substance is phase-separated by continuing stirring at the intensity of 1. In this step, it is possible to control the Feret diameter, the shape factor and the variation coefficient of the crystalline substance.

From the viewpoint of suppressing excessive charging of the toner particles and imparting uniform charging properties, the toner for developing an electrostatic charge image of the present invention comprises Metal element described above (as a form, metal,
250 to 20 in the toner)
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 as the aggregating agent and the monovalent metal element added as the aggregating terminator described later is 350 to 35,000 pp.
It is preferably m. X-ray fluorescence analyzer "System 3270" is used to measure the amount of residual metal ions in the toner.
It can be determined by measuring the intensity of fluorescent X-ray emitted from the metal species of the metal salt used as the aggregating agent (for example, calcium derived from calcium chloride) using [Rigaku Denki Kogyo KK]. As a specific measuring method, a plurality of toners having a known content ratio of the aggregating agent metal salt are prepared, 5 g of each toner is pelletized, the content ratio (mass ppm) of the aggregating agent metal salt, and the metal species of the metal salt. The relationship (calibration curve) with the fluorescent X-ray intensity (peak intensity) from is measured. Next, the toner (sample) whose content ratio of the aggregating agent metal salt is to be measured is pelletized in the same manner, and the fluorescent X-ray intensity from the metal species of the aggregating agent metal salt is measured to determine the content ratio, that is, "metal ion remaining in the toner You can ask for the "quantity".

[Filtration / Washing Step] In this filtration / washing step, a filtering treatment for filtering the toner particles from the dispersion system of the toner particles obtained in the above-mentioned step and the filtered toner particles (cake-shaped A cleaning process is performed to remove deposits such as surfactants and salting-out agents from the aggregate. Here, the filtration method is not particularly limited, such as a centrifugal separation method, a vacuum filtration method using a Nutsche or the like, or a filtration method using a filter press or the like.

[Drying Step] In this step, the washed toner particles are dried.

Examples of the dryer used in this step include a spray dryer, a vacuum freeze dryer, a vacuum dryer and the like. A stationary shelf dryer, a mobile shelf dryer, a fluidized bed dryer, a rotary dryer and a rotary dryer. It is preferable to use a dryer or a stirring dryer.

The water content of the dried toner particles is preferably 5% by mass or less, more preferably 2% by mass or less.

The toner particles that have been subjected to the drying treatment are
When the aggregates are aggregated by the weak attraction between particles, the aggregates may be crushed. Here, as the disintegration processing device,
A mechanical crushing device such as a jet mill, a Henschel mixer, a coffee mill or a food processor can be used.

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

Thus, by carrying out the preparation of 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 contamination of the fixing device and the image stain due to the accumulation of the toner do not occur.

Further, as a result of the polymerization reaction being surely carried out to obtain the composite resin particles, no monomer or oligomer remains in the obtained toner particles, and the image forming method using the toner can be used. No offensive odor is generated in the heat fixing step.

Further, the surface properties 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. Such a toner having a uniform composition, molecular weight, and surface characteristics among toner particles maintains good adhesiveness (high fixing strength) to an image support in an image forming method including a fixing step by a contact heating method. However, it is possible to improve the offset resistance and the anti-wrap property, and it is possible to obtain an image having an appropriate gloss.

Next, each constituent factor used in the toner manufacturing process will be described in detail. (Polymerizable Monomer) As the polymerizable monomer for producing the resin (binder) used in the present invention, a hydrophobic monomer is used as an essential constituent component, and a crosslinkable monomer is added as necessary. Used. Further, it is desirable to contain at least one kind of monomer having an acidic polar group or basic polar group in the structure as described below.

(1) Hydrophobic Monomer The hydrophobic monomer constituting the monomer component is not particularly limited, and conventionally known monomers can be used. Further, one kind or a combination of two or more kinds can be used so as to satisfy the required characteristics.

Specifically, a monovinyl aromatic monomer,
(Meth) acrylic acid ester-based monomer, vinyl ester-based monomer, vinyl ether-based monomer, monoolefin-based monomer, diolefin-based monomer, halogenated olefin-based monomer, etc. may be used. it can.

Examples of vinyl aromatic monomers include:
Styrene, o-methylstyrene, m-methylstyrene,
p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n- Examples thereof include styrene-based monomers such as octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4-dimethylstyrene, and 3,4-dichlorostyrene, and derivatives thereof. .

As the (meth) acrylic acid ester-based monomer, acrylic acid, methacrylic acid, methyl acrylate,
Ethyl acrylate, butyl acrylate, acrylic acid-2
-Ethylhexyl, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, γ-aminopropyl acrylate, methacrylic acid Stearyl, dimethylaminoethyl methacrylate,
Diethylaminoethyl methacrylate and the like can be mentioned.

Examples of the vinyl ester-based monomer include vinyl acetate, vinyl propionate, vinyl benzoate, and the like. Examples of the vinyl ether-based monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether. Etc.

As the monoolefin monomer, ethylene, propylene, isobutylene, 1-butene, 1-
Examples thereof include pentene and 4-methyl-1-pentene, and examples of the diolefin-based monomer include butadiene, isoprene and chloroprene.

(2) Crosslinkable Monomer A crosslinkable monomer may be added to improve the properties of the resin particles. Examples of the crosslinkable monomer include those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate and diallyl phthalate.

(3) Monomer having acidic polar group As the monomer having an acidic polar group, (a) an α, β-ethylenically unsaturated compound having a carboxyl group (—COOH), and (b) ) An α, β-ethylenically unsaturated compound having a sulfone group (—SO3H) can be mentioned.

Α, β-having a carboxyl group (a)
Examples of ethylenically unsaturated compounds include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid,
Examples thereof include cinnamic acid, maleic acid monobutyl ester, maleic acid monooctyl ester, and metal salts thereof such as Na and Zn.

Examples of the α, β-ethylenically unsaturated compound having a sulfone group (b) include sulfonated styrene and its Na salt, allylsulfosuccinic acid, octyl allylsulfosuccinate, and their Na salts. Can be mentioned.

(4) Monomer Having Basic Polar Group As the monomer having a basic polar group, (a) an amine group or a quaternary ammonium group having 1 to 1 carbon atoms
2, preferably 2 to 8, particularly preferably 2 (meth) acrylic acid ester of an aliphatic alcohol, (b) (meth)
Acrylic amide or optionally 1 to 1 carbon atoms on N
(Meth) acrylic acid amide mono- or di-substituted with 18 alkyl groups, (c) vinyl compound substituted with a heterocyclic group having N as a ring member, and (d) N, N-diallyl-alkylamine or a compound thereof. A quaternary ammonium salt can be illustrated. Among them, (meth) of aliphatic alcohol having an amine group or a quaternary ammonium group of (a)
Acrylic acid esters are preferred as the monomer having a basic polar group.

Examples of the (meth) acrylic acid ester of an aliphatic alcohol having an amine group or a quaternary ammonium group (a) include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, and the above. Quaternary ammonium salt of 4 compounds, 3-dimethylaminophenyl acrylate, 2-hydroxy-
3-methacryloxypropyl trimethyl ammonium salt etc. can be mentioned.

Examples of the (meth) acrylic acid amide (b) or the (meth) acrylic acid amide optionally substituted with mono- or dialkyl on N include acrylamide, N-butyl acrylamide, N, N-dibutyl acrylamide, piperidyl acrylamide, Methacrylamide, N-butylmethacrylamide, N, N-dimethylacrylamide,
N-octadecyl acrylamide etc. can be mentioned.

Examples of the vinyl compound (c) substituted with a heterocyclic group having N as a ring member include vinylpyridine, vinylpyrrolidone, vinyl-N-methylpyridinium chloride and vinyl-N-ethylpyridinium chloride. You can

Examples of (d) N, N-diallyl-alkylamine include N, N-diallylmethylammonium chloride and N, N-diallylethylammonium chloride.

(Polymerization Initiator) The radical polymerization initiator used in the present invention can be appropriately used if it is water-soluble. For example, persulfates (eg, potassium persulfate, ammonium persulfate, etc.), azo compounds (eg, 4,4 ′)
-Azobis-4-cyanovaleric acid and its salts, 2,2'-azobis (2-amidinopropane) salt, etc.), peroxide compounds and the like. Further, the above radical polymerization initiator can be combined with a reducing agent as required to form a redox initiator. By using the redox type initiator, the polymerization activity can be increased, the polymerization temperature can be lowered, and further the polymerization time can be shortened, which is a preferable aspect.

The polymerization temperature is not particularly limited as long as it is at least the minimum radical generation temperature of the polymerization initiator, but is, for example, in the range of 50 ° C to 90 ° C. However, it is also possible to carry out the polymerization at room temperature or higher by using a room temperature-initiated polymerization initiator in which a hydrogen peroxide-reducing agent (ascorbic acid or the like) is combined.

(Chain transfer agent) A known chain transfer agent can be used for the purpose of adjusting the molecular weight. The chain transfer agent is not particularly limited, for example, octyl mercaptan, dodecyl mercaptan,
A compound having a mercapto group such as tert-dodecyl mercaptan is used. In particular, a compound having a mercapto group is preferably used because it suppresses an odor at the time of heating and fixing, a toner having a sharp molecular weight distribution is obtained, and it has excellent storage stability, fixing strength, and offset resistance. Preferred are, for example, ethyl thioglycolate,
The mercapto group of propyl thioglycolate, propyl thioglycolate, butyl thioglycolate, t-butyl thioglycolate, 2-ethylhexyl thioglycolate, octyl thioglycolate, decyl thioglycolate, dodecyl thioglycolate, ethylene glycol is used. Examples thereof include compounds having a mercapto group of neopentyl glycol, and compounds having a mercapto group of pentaerythritol. Of these, from the viewpoint of suppressing odor during toner heat fixing, n-octyl-
Particularly preferred is 3-mercaptopropionic acid ester.

(Surfactant) It is preferable to disperse oil droplets in a water-based medium using a surfactant in order to carry out miniemulsion polymerization using the above-mentioned polymerizable monomer. The surfactant that can be used in this case is not particularly limited, but the following ionic surfactants can be mentioned as examples of suitable compounds.

Examples of the ionic surfactant include sulfonates (sodium dodecylbenzene sulfonate,
Aryl alkyl polyether sodium sulfonate,
3,3-disulfone diphenylurea-4,4-diazo-
Sodium bis-amino-8-naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol -6-
Sodium sulfonate, etc.), sulfate ester salts (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.),
Examples thereof include fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.).

In the present invention, the surfactants represented by the above general formulas (a) and (b) are particularly preferably used.

In the present invention, a metal salt can be preferably used as the aggregating agent in the step of salting out, aggregating and fusing the resin particles from the dispersion liquid of the resin particles prepared in an aqueous medium. It is further preferable to use a trivalent metal salt as the aggregating agent. The reason is that a divalent or trivalent metal salt is preferable to a monovalent metal salt because the critical aggregation concentration (coagulation value or coagulation point) is smaller.

In the present invention, a nonionic surfactant may be used. Specifically, polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, an ester of polyethylene glycol and a higher fatty acid, an alkylphenol. Examples thereof include polyethylene oxide, higher fatty acid and polyethylene glycol ester, higher fatty acid and polypropylene oxide ester, and sorbitan ester.

In the present invention, these surfactants are mainly used as an emulsifier during emulsion polymerization, but may be used for other steps or for other purposes.

(Molecular Weight Distribution of Resin Particles and Toner) The toner of the present invention has a peak or shoulder of 10 in the molecular weight distribution.
20,000 to 1,000,000, and 1,000 to 5
It is preferable that the peak or shoulder of the molecular weight distribution is 100,000 to 1,000,000.
0, 25,000-150,000 and 1,000-5
It is preferably present at 10,000.

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

The above-mentioned method for measuring the molecular weight of the toner or resin is carried out by using GP (THF) as a solvent.
Measurement by C (gel permeation chromatography) is preferable. That is, 1.0 ml of THF is added to 0.5 to 5 mg of the measurement sample, more specifically 1 mg, and stirred at room temperature using a magnetic stirrer or the like to sufficiently dissolve the sample. Next, pore size 0.45
After treatment with a 0.50 μm membrane filter,
Inject into GPC. The GPC measurement conditions are as follows: the column is stabilized at 40 ° C., THF is allowed to flow at a flow rate of 1.0 ml / min, and a sample having a concentration of 1 mg / ml is injected in an amount of about 100 μl. 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 combination and TSKgel G1000H, G200 manufactured by Tosoh Corporation
0H, G3000H, G4000H, G5000H, G
6000H, G7000H, TSK guard co
Examples include a combination of lumn. As a detector, a refractive index detector (IR detector) or U
A V detector may be used. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve prepared using monodisperse polystyrene standard particles. About 10 points may be used as polystyrene for preparing the calibration curve.

(Aggregating Agent) In the present invention, a metal salt can be preferably used as an aggregating agent in the steps of salting out, aggregating and fusing resin particles from a dispersion liquid of resin particles prepared in an aqueous medium. It is further preferable to use a divalent or trivalent metal salt as the aggregating agent. The reason is that a divalent or trivalent metal salt is preferable to a monovalent metal salt because the critical aggregation concentration (coagulation value or coagulation point) is smaller.

The aggregating agent used in the present invention is, for example, a monovalent metal salt which is a salt of an alkali metal such as sodium, potassium and lithium, for example, a salt of an alkaline earth metal such as calcium and magnesium and manganese and copper. Examples thereof include divalent metal salts and trivalent metal salts such as iron and aluminum.

Specific examples of these metal salts are shown below.
Examples of the monovalent metal salt include sodium chloride, potassium chloride, lithium chloride, and examples of the divalent metal salt include calcium chloride, zinc chloride, copper sulfate, magnesium sulfate, manganese sulfate, and the like. Examples include aluminum chloride and iron chloride. These are appropriately selected according to the purpose, but divalent or trivalent metal salts having a small critical aggregation concentration are preferable.

The critical coagulation concentration referred to in the present invention is an index relating to the stability of the dispersion in the aqueous dispersion, and shows the addition concentration of the coagulant when the coagulant is added and the coagulation occurs. This critical coagulation concentration greatly changes depending on the latex itself and the dispersant. For example, it is described in Seizo Okamura et al., Polymer Chemistry 17,601 (1960),
The value can be known by following these descriptions.
Further, as another method, a desired salt is added to the target particle dispersion liquid while changing the concentration, and the ζ potential of the dispersion liquid is measured,
It is also possible to set the salt concentration at the point where the ζ potential changes as the critical aggregation concentration.

In the present invention, the polymer fine particle dispersion is treated with a metal salt so as to have a concentration higher than the critical aggregation concentration. At this time, of course, directly add the metal salt,
Whether to add as an aqueous solution is arbitrarily selected according to the purpose. When it is added as an aqueous solution, the added metal salt needs to have a critical coagulation concentration of the polymer particles or more with respect to the volume of the polymer particle dispersion and the total volume of the metal salt aqueous solution.

In the present invention, the concentration of the metal salt may be equal to or higher than the critical aggregation concentration, but is preferably 1.
The amount is 2 times or more, more preferably 1.5 times or more.

The toner of the present invention is preferably obtained by salting out / fusing the above composite resin particles and colorant particles. Examples of the colorant constituting the toner of the present invention (colorant particles to be subjected to salting-out / fusion with the composite resin particles) include the various inorganic pigments, organic pigments and dyes described above. As the inorganic pigment, conventionally known ones can be used.

(Crystalline Material) In the toner used in the present invention, resin particles containing a crystalline material are fused in an aqueous medium, and the crystalline material is appropriately aggregated in an aging step to form a sea-island structure. It is preferable that the toner is a mixed toner. Thus, by salting out / fusing the resin particles containing the crystalline substance in the resin particles with the colorant particles in the aqueous medium, a toner in which the crystalline substance is finely dispersed can be obtained. Here, the aging step refers to a step of continuing stirring at a temperature within the range of the melting point of the crystalline substance ± 20 ° C even after the fusion of the resin particles.

In the toner of the present invention, as the crystalline substance having a releasing function, low molecular weight polypropylene (number average molecular weight = 1500 to 9000), low molecular weight polyethylene, etc. are preferable, and the ester represented by the following formula is particularly preferable. It is a system compound.

In the formula R _1- (OCO-R ₂ ) _n , n is an integer of 1 to 4, preferably 2 to 4, more preferably 3 to 4, and particularly preferably 4. R ₁ , R
₂ represents a hydrocarbon group which may have a substituent. R ₁
Has 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, and more preferably 2 to 5 carbon atoms. R ₂ has 1 to 40 carbon atoms, preferably 16 to 30 carbon atoms, and more preferably 18 to 26 carbon atoms.

Next, examples of typical compounds are shown below.

[0268]

[Chemical 7]

[0269]

[Chemical 8]

In the present invention, a crystalline polyester can be used as the crystalline substance. The crystalline polyester includes an aliphatic diol and an aliphatic dicarboxylic acid (including an acid anhydride and an acid chloride). And a polyester obtained by reacting

As the diol used for obtaining the crystalline polyester, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,
4-butanediol, 1,4-butenediol, neopentyl glycol, 1,5-pentane glycol, 1,
Examples include 6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, bisphenol Z, hydrogenated bisphenol A, and the like. it can.

The dicarboxylic acid used to obtain the crystalline polyester includes oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, maleic acid and fumaric acid. , Citraconic acid, itaconic acid, glutacoic acid, n-dodecylsuccinic acid, n-dodecenylsuccinic acid, isododecylsuccinic acid, isododecenylsuccinic acid, n-octylsuccinic acid, n-octenylsuccinic acid, their acid anhydrides or Mention may be made of acid chlorides.

Particularly preferred crystalline polyesters are polyesters obtained by reacting 1,4-cyclohexanedimethanol and adipic acid, polyesters obtained by reacting 1,6-hexanediol and sebacic acid, and ethylene. Polyester obtained by reacting glycol and succinic acid, polyester obtained by reacting ethylene glycol and sebacic acid, polyester obtained by reacting 1,4-butanediol and succinic acid can be mentioned. Of these, polyesters obtained by reacting 1,4-cyclohexanedimethanol and adipic acid are most preferable.

The amount of the above compound added is 1% by mass to 30% by mass, preferably 2% by mass to 20% by mass, and more preferably 3% by mass to 15% by mass, based on the whole toner.

(Developer) The toner of the present invention may be used as a one-component developer or a two-component developer. When used as a one-component developer, a non-magnetic one-component developer or a toner of 0. A magnetic one-component developer containing magnetic particles of about 1 to 0.5 μm can be used, and any of them can be used.

It is also possible to use it as a two-component developer by mixing it with a carrier. In this case, as the magnetic particles of the carrier, metals such as iron, ferrite and magnetite, and those metals and metals such as aluminum and lead are used. Conventionally known materials such as alloys of can be used. Ferrite particles are particularly preferable. The volume average particle diameter of the magnetic particles is 15 μm to 100 μm, and more preferably 25 μm.
It is m-80 micrometers.

The volume average particle diameter of the carrier is typically measured by a laser diffraction type particle size distribution measuring apparatus "HELOS" equipped with a wet disperser (SYMPATIC (SYMP).
(Made by ATEC)).

The carrier is preferably a carrier in which magnetic particles are further coated with a resin, or a so-called resin dispersion type carrier in which magnetic particles are dispersed in a resin. The resin composition for coating is not particularly limited, but, for example, an olefin resin, a styrene resin, a styrene-acrylic resin, a silicone resin, an ester resin, a fluorine-containing polymer resin, or the like is used. The resin for forming the resin-dispersed carrier is not particularly limited, and known ones can be used. For example, styrene-acrylic resin, polyester resin, fluorine resin, phenol resin, etc. are used. be able to.

Next, the image forming apparatus used in the image forming method using the toner of the present invention will be described.

In the present invention, the electrostatic latent image formed by charging and image exposure on the photoconductor is developed with a developer, and the formed toner image is transferred onto a transfer material by using a contact transfer system, and then transferred. By repeating each step of separation, fixing and cleaning,
A large number of images are formed.

(Transfer Roll) The toner image is transferred from the surface of the photoconductor to the transfer material by elastically pressing the transfer roll against the photoconductor and applying a bias voltage. As the transfer roll, an elastic body made of rubber or porous foam is used. For example, (1) Bridgestone's ion conductive type, (2) Bridgestone's electronic conductive type, (3) Toyo Polymer's foamed urethane rubicelle type, (4) Sumitomo Rubber Industries' ion conductive type, (5) Sumitomo EPDM type manufactured by Rubber Industries, (6) Epichlorohydrin type manufactured by Sumitomo Rubber Industries, (7) ENDUR manufactured by Inoac Corporation
Ion conductive type, (8) Tigers Polymer's foamed silicone type, (9) Hokushin Kogyo's foamed urethane type, (10) Shin-Etsu Polymer's foamed silicone type or (11) Nitto Kogyo's carbon black-containing Rubicell foamed type Although various types of transfer rolls such as the above can be mentioned, the foaming type is preferable.

In the image forming method used in the present invention, in order to satisfactorily transfer the toner image on the surface of the photoconductor to the transfer material, the pressing force of the transfer roll to the photoconductor is 2.5 to 1.
00 kPa is preferable, and more preferably 10 to 80 kP.
a.

The pressing force is 2.5 kPa to 100 kPa
In that case, the transfer of the toner image will be sufficient, and the transfer of the crystalline substance having releasability in the toner to the surface of the photoreceptor can be prevented, and the occurrence of image defects can also be prevented. Also,
The impact at the time of releasing the pressure of the transfer roll is reduced, image defects due to transfer deviation can be prevented, and damage to the photoconductor can also be prevented.

Further, as the characteristics required for the transfer roll, for example, the impact resilience, the electric resistance, the surface hardness, etc. are important. The impact resilience of the elastic body of the transfer roll is preferably 30% to 70%. When the impact resilience is 30 to 70%, a sufficient pressing force to the photoconductor is obtained for transferring the toner image, a good transfer rate is obtained, and the impact at the time of transfer can be reduced, so that the transfer deviation is caused. It is possible to prevent the occurrence of image defects such as. The impact resilience is measured by the measuring method of JIS K7311.

The transfer roll is required to have an appropriate conductivity so that a bias voltage for toner image transfer can be applied, and the electric resistance value measured by the following measuring method is 1
It is preferable that it is × 10 ³ to 1 × 10 ¹³ Ω.

<Measurement method> Diameter 16 mm, length 310 mm
The transfer roll in which an elastic body having a thickness of 4 mm is provided on the rotating shaft of No. 2 is pressed against an aluminum tube having a diameter of 30 mm with a force of 17 kPa, and the rotating shaft of the transfer roll is set at 20 ° C. and 50% RH. Measure the electrical resistance between the aluminum tubes.

The surface hardness of the elastic body measured by an Asker C hardness meter is preferably 20 to 70 degrees. A transfer roll made of an elastic material having an Asker C hardness of 20 to 70 degrees is preferable because transfer is performed properly and image defects such as transfer deviation do not occur.

Next, the image forming apparatus used in the image forming method for forming a large number of images of the present invention will be described with reference to the drawings. The image forming method for forming a large number of images of the present invention means that an electrostatic latent image formed by performing charging and image exposure on a photoconductor is used as a developer containing a toner for developing an electrostatic latent image. It is an image forming method in which a toner image formed by development is transferred to a transfer material by using a contact transfer method, and then each step of separating, fixing and cleaning is repeated to form a large number of images.

FIG. 6 is a schematic block diagram showing an example of an image forming apparatus using a transfer roll. In FIG. 6, the photoconductor 10
Is an organic photoconductor rotating in the direction of the arrow, 11 is a charger for uniformly charging the photoconductor, and the charger may be a corona discharger, a roller charger, or a magnetic brush charger. . Reference numeral 12 denotes a digital image exposure light using a semiconductor laser, a light emitting diode, etc., and an electrostatic latent image is formed on the photoconductor by the image exposure light. This electrostatic latent image is developed in a contact or non-contact manner by a developing device 13 containing a developer containing a toner having a volume average particle diameter of 3 to 9 μm, and a toner image is formed on the photoreceptor. In the present invention, digital image exposure is particularly preferable as the exposure, but analog image exposure may be performed.

As a scanning optical system that is optically modulated by a digital image signal from a computer or a copy original employed in this image forming method and apparatus, an acousto-optic modulator is interposed in a laser optical system, and the acousto-optic modulator is used to emit light. There is a device for modulating and a device for directly modulating the laser intensity by using a semiconductor laser. These scanning optical systems perform spot exposure on a uniformly charged photoconductor to form a dot-shaped image.

The beam emitted from the above-mentioned scanning optical system has a circular or elliptical luminance distribution which has a hem spread to the left and right and approximates a normal distribution. For example, in the case of a laser beam, it is usually the main beam on the photoconductor. One or both of the scanning direction and the sub-scanning direction is an extremely narrow round or elliptical shape of 20 to 100 μm.

The toner image is transferred onto the transfer material P, which is conveyed at the same timing, by the transfer roll 15 under the application of a DC bias with a pressing force of 2.5 to 100 kPa, preferably 10 to 80 kPa.

The DC bias power supply 16 for applying a bias to the transfer roll 15 is preferably a constant current power supply or a constant voltage power supply, and in the case of the constant current power supply, it is 5 to 15 μA.
In the case of a constant voltage power supply, the absolute value is 400 to 1500
V. The transfer material P on which the image has been transferred by the transfer roll 15 is separated from the photoconductor 10 by the separation electrode 14 and is conveyed to a fixing device (not shown) to be heated and fixed.

The surface of the photoconductor after transfer is cleaned by the cleaning blade 17 and then discharged by the discharge lamp (PCL) 18 to prepare for the next image formation. Reference numeral 19 is a paper feed roller, and 20 is a fixing device.

(Intermediate Transfer Member) In the present invention, the transfer of the toner image from the photosensitive member to the transfer material can also be performed by a system using an intermediate transfer member. That is, an image forming unit (image forming unit) is provided for each of the four color developers, a visible image for each color is formed on each photoconductor in each image forming unit, and these visible images are sequentially transferred to an intermediate transfer member. After being collectively transferred to a transfer material (usually plain paper, it is not particularly limited as long as it can be transferred. In particular, an OHP sheet is preferable as the transfer material in the present invention) and then fixed to form a color image. It can also be preferably used in the method of obtaining.

An image forming method in which images of a plurality of colors used in the image forming apparatus of the present invention are formed in the image forming section and are sequentially transferred to the same intermediate transfer member in a superimposing manner will be described with reference to the drawings. . FIG. 7 is a schematic configuration diagram showing an example of an image forming apparatus using an intermediate transfer body (transfer belt).

In FIG. 7, the image forming apparatus for obtaining a color image is provided with a plurality of image forming units, each image forming unit forms a visible image (toner image) of a different color, and the toner image is formed. This is an image forming method in which images are sequentially transferred and superposed on the same intermediate transfer member.

Here, the first, second, third and fourth image forming units Pa, Pb, Pc and Pd are arranged in parallel, and each of the image forming units is a photosensitive member which is an electrostatic latent image forming body. It comprises bodies 1a, 1b, 1c and 1d. The photoconductors 1a, 1b, 1c and 1d have the latent image forming portion 2 on the outer peripheral side thereof.
a, 2b, 2c and 2d, developing portions 3a, 3b, 3c and 3d, transfer discharge portions 4a, 4b, 4c and 4d, a cleaning device 5 having a cleaning member and a rubber blade
a, 5b, 5c and 5d, and chargers 6a, 6b, 6c and 6d are arranged.

With such a structure, first, a latent image forming section 2a forms a latent image of, for example, a yellow component color in the original image on the photoconductor 1a of the first image forming unit Pa. The latent image is formed into a visible image with the developer containing yellow toner in the developing section 3a, and transferred to the transfer belt 21 in the transfer discharge section 4a.

On the other hand, while the yellow toner image is being transferred to the transfer belt 21 as described above, a latent image of magenta component color is formed on the photoconductor 1b in the second image forming unit Pb, and then the developing unit is formed. In 3b, a visible image is formed with a developer containing magenta toner. The visible image (magenta toner image) is transferred to the predetermined position of the transfer belt 21 in an overlapping manner when the transfer belt, which has been transferred by the first image forming unit Pa, is carried into the transfer discharge section 4b. It

Thereafter, the third and fourth steps are performed in the same manner as described above.
The image forming units Pc and Pd form images of cyan component color and black component color, respectively, and the cyan toner image and the black toner image are superposedly transferred onto the same transfer belt. When such an image forming process is completed, a multicolor superimposed image is obtained on the transfer belt 21. On the other hand, the residual toners are removed from the photoconductors 1a, 1b, 1c and 1d after the transfer by the cleaning devices 5a, 5b, 5c and 5d, and the photoconductors are provided for the subsequent latent image formation.

In the image forming apparatus, the transfer belt 21 is used. In FIG. 7, the transfer belt 21 is used.
Is conveyed from the right side to the left side, and in the course of the conveyance, each color transfer image is transferred through each of the transfer discharge parts 4a, 4b, 4c and 4d in each of the image forming units Pa, Pb, Pc and Pd.

The transfer belt 21 is the fourth image forming unit P.
After passing d, an AC voltage is applied to the separation charge-eliminating discharger 22d, the transfer belt 21 is discharged, and the toner images are collectively transferred to the transfer material P. After that, the transfer material P enters the fixing device 23, is fixed, and is discharged from the discharge port 25 to obtain a color image.

Incidentally, reference numerals 22a, 22b, 22c and 22d in the figure are separation charge-eliminators, and the transfer belt 21 which has completed the transfer of the toner image is cleaned by a cleaning device 24 using a brush-like cleaning member and a rubber blade in combination. The transfer residual toner is cleaned and prepared for the next image formation.

As described above, even if a long transfer belt 21 such as a conveyor belt is used and a multicolor superimposed image is formed on the transfer belt 21 and the transferred images are collectively transferred to a transfer material, the image is not transferred. The forming units may be provided with independent transfer belts, and the transfer belts may be sequentially transferred to the transfer material.

As the transfer belt, for example, a high resistance film having a surface resistance of 1014 Ω or more and a thickness of about 20 μm, such as polyimide, polyether, polyamide or tetrafluoroethylene / perfluorovinyl ether copolymer, is used. A conductive agent was added to fluorine-based or silicon-based resin to make the surface resistance 105 to 108Ω.
An endless film provided with a release layer having a thickness of ˜15 μm is used.

In the image forming method of the present invention, the toner image formed in the developing step is fixed in the fixing step after being transferred to the transfer material as described above. A so-called contact heating method can be mentioned as a suitable fixing method used in the present invention. In particular, as the contact heating method, there are a heat pressure fixing method, a heat roll fixing method, and a pressure contact heating fixing method in which fixing is performed by a rotating pressure member including a fixedly arranged heating body.

In the hot roll fixing system, an upper roller having a heat source inside a metal cylinder made of iron or aluminum whose surface is coated with tetrafluoroethylene or polytetrafluoroethylene-perfluoroalkoxy vinyl ether copolymers is used. It is formed of a lower roller made of silicone rubber or the like. As a heat source, a linear heater is used, and the surface temperature of the upper roller is 120 to
A typical example is heating to about 200 ° C. In the fixing section, pressure is applied between the upper roller and the lower roller to deform the lower roller and form a so-called nip. The nip width is 1 to 10 mm, preferably 1.5 to 7 mm. The fixing linear velocity is 40 mm / sec to 600 mm / se
c is preferred. When the nip is narrow, heat cannot be uniformly applied to the toner, resulting in uneven fixing. On the other hand, when the nip width is wide, melting of the resin is promoted, causing a problem of excessive fixing offset.

A fixing cleaning mechanism may be provided for use. As this method, a method of supplying silicone oil to a roller or a film after fixing, or a method of cleaning with a pad, roller, web, etc. impregnated with silicone oil can be used.

Next, a method of fixing by a rotating pressure member containing a fixedly arranged heating element used in the present invention will be described.

This fixing system is a system in which a heating member fixedly arranged and a pressing member which is in pressure contact with the heating member and is in contact with the heating member to bring the transfer material into close contact with the heating member through pressure contact heat fixing.

In this pressure contact heat fixing device, the heating body has a smaller heat capacity than the conventional heating roller, and has a linear heating portion in the direction perpendicular to the passing direction of the transfer material. Is 100 to 300 ° C.

The pressure contact heat fixing is carried out by pressing an unfixed toner image against a heating source, such as a method of passing a transfer material containing unfixed toner between a heating member and a pressure member. Is the way. By such measures, the heating is performed quickly, so that the fixing can be speeded up.

In this fixing system, the low heating capacity linear heating element fixedly supported by the apparatus has a thickness of 0.2-5.
0 mm, more preferably 0.5 to 3.5 mm and width 10
An alumina substrate having a length of ˜15 mm and a longitudinal length of 240 to 400 mm is coated with a resistance material to have a thickness of 1.0 to 2.5 mm.

Energization is carried out at a DC100V cycle of 15 to 25 m.
With a pulse waveform of sec, the pulse width is changed and given according to the temperature and the amount of energy released controlled by the temperature sensor. In the low heat capacity linear heating element, when the temperature is T1 detected by the temperature sensor, the surface temperature T2 of the film facing the resistance material is lower than T1. Here, T1 is preferably 120 to 220 ° C., and the temperature of T2 is preferably 0.5 to 10 ° C. lower than the temperature of T1. The surface temperature T3 of the film material at the portion where the film peels from the toner surface is almost equal to T2. The film comes into contact with the heating body whose energy and temperature are controlled in this way, and moves in the direction of the central arrow in FIG. Those used as fixing films are heat-resistant films having a thickness of 10 to 35 μm, for example, polyester, polyperfluoroalkoxy vinyl ether, polyimide, polyetherimide, and in many cases fluorocarbon resin such as Teflon (R) as a conductive material. Is an endless film having a release agent layer coated with 5 to 15 μm.

To drive the film, a driving force and a tension are applied by the driving roller and the driven roller, and the film is conveyed in the direction of the arrow without wrinkling or twisting. The linear velocity of the fixing device is preferably 230 to 900 mm / sec.

The pressure roller has a rubber elastic layer having a high releasability such as silicone rubber, and is pressed against a heating body through a film material and rotated under pressure.

Although the example using the endless film has been described above, as shown in FIG. 5 (b), the feeding shaft and the winding shaft of the film sheet are used, and the endless film material is used. Good. Further, it may be a simple cylinder without a drive roller or the like inside.

A cleaning mechanism may be added to the fixing device for use. As a cleaning method, a method of supplying various silicone oils to the fixing film or a method of cleaning with a pad, a roller, a web or the like impregnated with various silicone oils is used.

As the silicone oil, polydimethylsiloxane, polymethylphenylsiloxane, polydiphenylsiloxane, etc. can be used. Further, a siloxane containing fluorine can also be preferably used.

Next, FIG. 5 shows an example of a sectional view of the structure of this fixing device. In FIG. 5A, reference numeral 84 is a low heat capacity linear heating element fixedly supported by the apparatus, and as an example, a resistance material 86 is provided on an alumina substrate 85 having a height of 1.0 mm, a width of 10 mm, and a longitudinal length of 240 mm. Is applied to have a width of 1.0 mm, and electricity is applied from both ends in the longitudinal direction.

The energization is carried out in the form of a pulsed waveform with a cycle of, for example, 20 msec at a voltage of DC 100 V and is maintained at a predetermined temperature controlled by a signal from the temperature measuring element 87.
For this reason, the pulse width is changed according to the amount of energy released, and the range is, for example, 0.5 to 5 msec. The toner is thermally fixed by bringing the transfer material 94 carrying the unfixed toner image 93 into contact with the heating member 84 controlled in this way through the moving film 88.

The film 88 used here moves without wrinkles in a state where tension is applied by the driving roller 89 and the driven roller 90. Reference numeral 95 is a pressure roller having a rubber elastic layer formed of silicone rubber or the like, and presses the heating body through the film at a total pressure of 0.4 to 2.0 N. Unfixed toner image 93 on transfer material 94
Is guided to the fixing portion by the entrance guide 96, and a fixed image is obtained by heating.

Although the endless belt has been described above, as shown in FIG. 5B, a film sheet feeding shaft 91 and a winding shaft 92 may be used, and the fixing film may have an end.

[0325]

The present invention will be described in detail below with reference to examples, but the embodiments of the present invention are not limited thereto. In addition, "part" in a sentence represents a "mass part."

Example 1 <Production of Colorant> (Production of Comparative Colorant 1Y: Production Example Using Pigment Yellow 74) 2-Methoxy-4-nitro-aniline 1
82.7 parts and 5.1 parts of 2-nitro-4-methylaniline were added to a mixture of 1,300 parts of water and 290 parts of 35% hydrochloric acid and stirred, and then cooled to 0 ° C., sodium nitrite. Add 80 parts to diazotize. Separately, 241.8 parts of 2-methoxyacetoacetanilide was added to 5,000 parts of water, dissolved together with 48 parts of sodium hydroxide, and then precipitated by adding a mixed solution of 196 parts of acetic acid and 196 parts of water. A suspension of coupling components is obtained. The clear diazo solution is added to the acetic acid suspension of the above-mentioned coupling component by flowing down with stirring well at 15 ° C. within 1 hour 30 minutes to 2 hours.

After the completion of the coupling reaction, the pigment composition was treated with 45 parts of rosin and 13 parts of calcium chloride, and the obtained pigment composition was filtered and washed with water. Agent 1Y was obtained.

The THF (tetrahydrofuran) elution content of the obtained comparative colorant 1Y was 34,500 ppm. Here, the amount of THF eluate was measured by the method described above.

(Production of Colorant 1Y: Production Example Using Pigment Yellow 74) The above comparative colorant 1Y was washed with 50 times amount of solid content of acetone, and then washed with 50 times amount of methanol similarly. After that, a substitution treatment with water was performed to obtain a pigment water wet pigment paste-like colorant 1Y having a pigment solid content of 24%.

The THF (tetrahydrofuran) elution of the obtained colorant 1Y was 3,420 ppm.

(Production of Colorant 2Y: Production Example Using Pigment Yellow 74) Pigment solid was prepared in the same manner as in the production of Colorant 1Y, except that the washing conditions were 20 times the amount of acetone and 20 times the amount of methanol. A coloring agent 2Y in the form of a pigment water-moist pigment paste having a content of 23% was obtained.

The THF (tetrahydrofuran) elution content of the obtained colorant 2Y was 5,780 ppm.

(Production of Colorant 3Y: Production Example Using Pigment Yellow 180) Toner Yellow H
G (manufactured by Hoechst) was washed with 30 volumes of acetone and 30 volumes of methanol, and then subjected to a displacement treatment with water to obtain a pigment-wet pigment paste-like colorant 3Y having a pigment solid content of 25%.

The eluate of the obtained colorant 3Y in THF (tetrahydrofuran) was 210 ppm.

(Production of colorant 4Y: Production example using Pigment Yellow 180) Production of colorant 3Y except that the washing conditions were 60 times the amount of acetone and 60 times the amount of methanol, and then replaced with water. Similarly, pigment solids 25%
Pigment water-wet pigment paste-like colorant 4Y was obtained.

The eluate of THF (tetrahydrofuran) of the obtained colorant 4Y was 80 ppm.

(Production of comparative colorant 2Y) Washing condition 1
Comparison of pigment solid content 25% in the same manner as in the production of Colorant 3Y except that after washing with 20 times amount of acetone, 30 times amount of diethyl ether-benzene mixed solvent, and further 120 times amount of methanol, and then substituting with water. As a water-moist pigment paste, a comparative coloring agent 2Y was obtained.

The THF (tetrahydrofuran) elution of the obtained comparative colorant 2Y was 20 ppm.

(Production of Comparative Colorant 3R) 3-Amino-
50 parts of 4-methoxybenzanilide (0.21 mol)
Was dispersed in 1000 parts of water, ice was added to set the temperature condition of 0 ° C. to 5 ° C., 55 parts (0.53 mol) of 35% hydrochloric acid aqueous solution was added, and the mixture was stirred for 30 minutes. Then, 50 parts (0.22 mol) of 30% sodium nitrite aqueous solution was added and stirred for 60 minutes, and then 2 parts (0.02 mol) of sulfamic acid was added to remove excess nitrous acid. Furthermore, sodium acetate 40 parts (0.29 mol), 90% acetic acid 58 parts (0.87 mol)
Was added to prepare a diazonium salt solution.

Separately, 5 parts of N- (5-chloro-2-methoxyphenyl) -3-hydroxy-2-naphthoic acid (0.
(03 mol) was dissolved with 1000 parts of water and 25 parts (0.63 mol) of caustic soda (sodium hydroxide) at a temperature of 80 ° C. or lower to obtain a coupler solution.

The resulting coupler solution was added to the above diazonium salt solution under a temperature condition of 10 ° C. or lower, a coupling reaction was carried out, heat treatment was carried out at 90 ° C., and the obtained reaction mixture was filtered and washed with water. After doing, dry at 100 ℃,
It was crushed.

After crushing, a particle size distribution measuring device (CAPA-7
00: manufactured by Horiba, Ltd.), and 110 parts of a pigment composition having an average particle size D50 according to cumulative volume distribution of 0.06 μm was obtained. The molecular structure of the pigment is shown below.

[0343]

[Chemical 9]

Next, the pigment composition was prepared into an aqueous slurry, an aqueous solution of sodium salt of rosin was added, and further barium chloride was added to coat the surface of the pigment with an insoluble metal salt of rosin to prepare a water-wet pigment paste. Comparative colorant 3R was obtained.

The THF (tetrahydrofuran) elution of the obtained comparative coloring agent 3R was 25,200 ppm.

(Production of Coloring Agent 5R) The comparative coloring agent 3R was washed with 10 times the amount of solid content of acetone, and similarly with 10 times the amount of methanol, and then replaced with water to give a pigment solid content of 2
4% of pigment water wet pigment paste colorant 5R was obtained.

The THF (tetrahydrofuran) elution content of the obtained colorant 5R was 9,680 ppm.

(Production of Colorant 6R) The same as in the production of Colorant 5R except that the washing conditions were washed with 90 times amount of acetone and 90 times amount of methanol, and then replaced with water. A pigment water wet pigment paste-like colorant 6R was obtained.

The THF (tetrahydrofuran) elution of the obtained colorant 6R was 50 ppm.

<< Production of Resin Particles for Toner >> (Preparation of Latex 1HML) (1) Preparation of Core Particles (First Stage Polymerization): Preparation of Latex 1H Stirrer, temperature sensor, cooling tube, nitrogen introducing device were attached. In a 5000 ml separable flask, 7.08 g of the following anionic surfactant (101) (101) C ₁₀ H ₂₁ (OCH ₂ CH ₂ ) ₂ OSO ₃ Na was dissolved in 3010 g of ion-exchanged water. (Aqueous medium) is charged and under nitrogen stream 230r
The internal temperature was raised to 80 ° C. while stirring at a stirring speed of pm.

To this surfactant solution, 9.2 g of a polymerization initiator (potassium persulfate: KPS) was added 200 g of ion-exchanged water.
Was added to the solution of the initiator, and the temperature was adjusted to 75 ° C. Then, 70.1 g of styrene and 1 of n-butyl acrylate were added.
A monomer mixture liquid consisting of 9.9 g and methacrylic acid 10.9 g was added dropwise over 1 hour, and the system was heated and stirred at 75 ° C. for 2 hours to perform polymerization (first stage polymerization), A latex (dispersion of resin particles composed of a high molecular weight resin) was prepared. This is designated as "latex (1H)".

(2) Formation of intermediate layer (second-stage polymerization): Preparation of latex 1HM In a flask equipped with a stirrer, styrene 1 was added.
A monomer mixture consisting of 05.6 g, n-butyl acrylate 30.0 g, methacrylic acid 6.2 g, and n-octyl-3-mercaptopropionic acid ester 5.6 g was added as a crystalline substance to the above formula (19). A compound solution was prepared by adding 98.0 g of the compound represented by the following (hereinafter referred to as “Exemplified Compound (19)”) and heating to 90 ° C. to dissolve.

On the other hand, an anionic surfactant (the above formula (1
01)) 1.6 g of ion-exchanged water dissolved in 2700 ml of a surfactant solution was heated to 98 ° C., and the latex solution (1H) as a dispersion of core particles was added to the surfactant solution.
After adding 28 g of solid content, a mechanical dispersion machine with a circulation path "CLEARMIX"
(Manufactured by M Technique Co., Ltd.), a monomer solution of the exemplified compound (19) is mixed and dispersed for 8 hours, and a dispersion liquid (emulsion liquid) containing emulsified particles (oil droplets) having a dispersed particle diameter (284 nm). ) Was prepared.

Then, to this dispersion (emulsion), an initiator solution prepared by dissolving 5.1 g of a polymerization initiator (KPS) in 240 ml of ion-exchanged water and 750 ml of ion-exchanged water were added, and this system was added to 98 Polymerization (second-stage polymerization) is performed by heating and stirring at ℃ for 12 hours to obtain latex (dispersion liquid of composite resin particles having a structure in which the surface of resin particles made of high molecular weight resin is coated with intermediate molecular weight resin). Obtained. This is designated as "latex (1HM)".

When the latex (1HM) was dried and observed with a scanning electron microscope, particles (4) containing the exemplary compound (19) not surrounded by the latex as a main component
(0 to 1000 nm) was observed.

(3) Formation of Outer Layer (Third Stage Polymerization): Preparation of Latex 1HML In the latex (1HM) obtained as described above, 7.4 g of a polymerization initiator (KPS) was dissolved in 200 ml of deionized water. The added initiator solution was added, and under the temperature condition of 80 ° C., 300 g of styrene and 95% of n-butyl acrylate were added.
g, 15.3 g of methacrylic acid, and 10.4 g of n-octyl-3-mercaptopropionic acid ester were added dropwise over 1 hour. After completion of dropping, polymerization (third stage polymerization) was carried out by heating and stirring for 2 hours, followed by cooling to 28 ° C. and latex (a central portion made of a high molecular weight resin, an intermediate layer made of an intermediate molecular weight resin, and a low layer). A dispersion liquid of composite resin particles, which has an outer layer made of a molecular weight resin and in which the exemplary compound (19) is contained in the intermediate layer)
Got This latex is "latex (1HML)"
And

The composite resin particles constituting this latex (1HML) are 138,000, 80,000 and 1
Has a peak molecular weight of 3,000, and
The volume average particle size of the composite resin particles was 122 nm.

<Production of Toner> (Preparation of Colorant Particle Dispersions 1 to 6) 59.0 g of an anionic surfactant (sodium dodecyl sulfate) was dissolved in 1600 ml of ion-exchanged water with stirring, and while stirring this solution, The colorants 1Y to 4Y, the colorants 5R and 6R, and the comparative colorants 1Y, 2Y, and 3R are combined as shown in Table 2 and 420.
Dispersions 1 to 6 of colorant particles were respectively prepared by gradually adding 0 g (corresponding to solid content) and then performing dispersion treatment using "CLEARMIX" (manufactured by M Technique Co., Ltd.).

(Production of Toners 1 to 6 and Comparative Toners 1 to 3) Latex 1HML 420.7 g (solid content conversion)
, 900 g of ion-exchanged water, and 166 g of the above colorant dispersion liquid 1, a temperature sensor, a cooling pipe, a nitrogen introducing device,
The mixture was placed in a reaction vessel (four-necked flask) equipped with a stirrer and stirred. After adjusting the temperature in the container to 30 ° C., a 5 mol / liter sodium hydroxide aqueous solution was added to this solution to adjust the pH to 8.

Then, magnesium chloride hexahydrate 1
An aqueous solution obtained by dissolving 2.1 g in 1000 ml of ion-exchanged water was added with stirring at 30 ° C. for 10 minutes. The temperature was started after standing for 3 minutes, and the system was heated to 90 ° C. over 6 to 60 minutes to generate associated particles. In that state, the particle diameter of the associated particles was measured with "Coulter Counter TA-II", and when the number average particle diameter reached 4 to 7 µm, 80.4 g of sodium chloride was added to the ion-exchanged water 10
An aqueous solution dissolved in 00 ml was added to stop grain growth, and further aging treatment was performed at a liquid temperature of 85 to 98 ° C. for 2-1.
By heating and stirring for 2 hours, fusion of particles and phase separation of crystalline material were continued (aging step).

Then, the mixture was cooled to 30 ° C., hydrochloric acid was added to adjust the pH to 2.0, and stirring was stopped. The formed associated particles were filtered, washed repeatedly with ion-exchanged water at 45 ° C., and then dried with warm air at 40 ° C., and then mixed with 1% by mass of hydrophobic silica, thereby developing developers 1 to 6 and Comparative developers 1 to 3 were obtained.

Here, the relationship between the physical characteristics of the toner particles for developing an electrostatic charge image and the colored particles according to the present invention will be described.

In the production of the colored particles according to the present invention,
The resin particles and the colorant are monitored during the salting out / fusion step and the shape control process, and the reaction coefficient such as the rotation speed of stirring and the heating time is controlled to control the coefficient of variation of the shape and the shape coefficient to determine the particle size and the particle size. Adjust the coefficient of variation of the distribution. Toner particles are produced by adding an external additive to the thus obtained colored particles, but the external additive is merely fixed to the surface of the toner particles and there is no physical change in the colored particles. The physical properties (shape, particle size, etc.) of the toner particles are the same as those of the colored particles.

Obtained Toners 1 to 6 and Comparative Toner 1
Table 1 shows the physical properties of ~ 3.

[0365]

[Table 1]

<< Production Example of Photoreceptor >> (Production of Photoreceptor P2) A photoreceptor P2 was produced by coating the following coating liquid on a cylindrical conductive support.

<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 conductivity using the above coating liquid. A film thickness of 0.
It was applied so as to have a thickness of 5 μm.

<Charge Generation Layer> Titanyl phthalocyanine (*) 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 are mixed and dispersed for 10 hours using a sand mill, A charge generation layer coating solution was prepared. This coating solution was applied onto the undercoat layer by a dip coating method to form a charge generation layer having a thickness of 0.2 μm.

*: Y-type titanyl phthalocyanine (Cu-
Bragg angle 2θ in Kα characteristic X-ray diffraction spectrum measurement
(Maximum peak at 27.2 degrees of ± 0.2) <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 components were mixed and dissolved to prepare a charge transport layer coating liquid.
This coating solution was applied onto the charge generation layer by a dip coating method to form a charge transport layer having a dry film thickness of 20 μm.

<Protective Layer> Methyltrimethoxysilane 150 g Dimethyldimethoxysilane 30 g Reactive charge transporting compound (Exemplary compound B-1) 15 g Polyvinylidene fluoride particles (volume average particle size 0.2 μm) 10 g Antioxidant (Exemplary compound 2-1) 0.75 g 2-propanol 75 g 3% acetic acid 5 g The above materials were mixed to prepare a coating liquid for a resin layer. A resin layer having a thickness of 2 μm is formed on the charge transport layer by using the coating liquid on the charge transport layer, and the resin layer is heated and cured at 120 ° C. for 1 hour to form a siloxane resin layer.
2 was produced.

[0371]

[Chemical 10]

[0372]

[Chemical 11]

[0373]

[Chemical 12]

An image was formed using the image forming apparatus shown in FIG. 7 on the obtained photoconductor P2 using a modified machine mounted on a commercially available digital copying machine Konica Sitios 7030.
The toners 1 to 6 produced above and the toners 1 to 3 for comparison were each evaluated as follows.

As a developing unit, 25 as a toner conveying member.
The toner replenishing auxiliary member had a diameter of 20 mm. Further, as the toner layer regulating member, one made of urethane rubber was used, and the contact pressure thereof was 0.6 N / cm. The copy speed was modified to A4, 20 sheets / minute (ppm), and the actual copying evaluation was carried out. The organic photoconductor P2 was used as the photoconductor.
Further, the untransferred toner remaining on the photoconductor is cleaned by a blade cleaning method.

As the fixing method, the fixing device shown in FIG. 5A was used and the temperature was set to 170 ° C. As the image forming condition, a line drawing having a pixel ratio of 5% was used in a high temperature and high humidity environment (30 ° C., 85% RH), and 50,000 sheets were printed by a one-sheet intermittent printing method.

<< Evaluation of OHP image transparency (OHP transparency) >> The developers 1 to 6 of the present invention and the comparative developers 1 to 3 were
A transmission image (OHP image) was produced (fixing temperature was 170 ° C.) on a commercially available OHP resin film, and OHP transparency was evaluated by the following method. The toner adhesion amount was adjusted to be in the range of 0.7 ± 0.05 (mg / cm ² ).

With respect to the fixed image, the visible spectral transmittance of the image was measured with an OHP sheet on which no toner was carried, as a reference, by a "330 type self-recording spectrophotometer" manufactured by Hitachi, Ltd., and colorants 1Y to 4Y were used for comparison. Colorant 1
For yellow toner such as Y and 2Y, 650 nm and 45
The difference in spectral transmittance at 0 nm and the difference in spectral transmittance between 650 nm and 550 nm for magenta toners such as colorants 5R and 6R and comparative colorant 3R were determined and used as a measure of the transparency of the OHP image. When this value was 70% or more, it was determined that the transparency was good.

<< Evaluation of Uniformity of Halftone >> Density of 10% halftone dot: For a 10% halftone dot image area of 20 mm × 20 mm, a relative image density with respect to a white background portion was measured using a Macbeth reflection densitometer “RD-918”. did. 10%
The halftone dot density was evaluated in order to evaluate the dot reproducibility and halftone reproducibility. If the density change is within 0.10, the change in image quality is small and it can be said that there is no problem.

<< Image Sharpness >> Line width: The line width of a line image corresponding to a 2-dot line image signal is evaluated by the printing evaluation system "RT2000".
(Manufactured by Yerman Co., Ltd.). If both the line width of the first formed image and the line width of the 20,000th formed image are 200 μm or less, and the change in line width is less than 10 μm, the result is ◯, and the change in width is 10 μm.
The above was ranked as x.

<Evaluation of Fixation Offset Occurrence> After transporting and fixing 10,000 A4 images having a solid band-shaped image having a width of 5 mm in the vertical direction in the vertical direction, the halftone having a width of 20 mm is perpendicular to the transport direction. A4 images having images are continuously fed in a horizontal direction of 10,000 sheets and paused. After stopping the machine overnight, the machine was restarted, and the presence or absence of image stains due to the fixing offset phenomenon occurring on the first first sheet and the stain state of the pad were visually evaluated, and the rank evaluation was performed as follows.

A: No stains on the image and almost no stains on the pad B: No stains on the image, but stains are accumulated on the pad C: Very slight stains on the image Occurrence (no problem in practical use) D: Minor stains on the image (some problems in practice) E: Fog evaluation not suitable for practical use <Fog evaluation> Macbeth reflection on unprinted white paper Absolute image densities at 20 locations are measured using a densitometer "RD-918" and averaged to obtain a blank sheet density. Next, with respect to the white background portion of the evaluation formed image, the absolute image densities at 20 locations were similarly measured and averaged, and the value obtained by subtracting the white paper density from the average density was evaluated as the fog density. If the fog density is 0.010 or less, it can be said that the fog is practically no problem.

<< Filming of Photoreceptor >> The presence or absence of filming was ranked as follows by visually observing the surface of the photoreceptor after 500,000 continuous copies.

None: No fogging on the photosensitive member, no filming was confirmed Yes: Filming was confirmed on the photosensitive member The obtained results are shown in Table 2.

[0385]

[Table 2]

From Table 2, as compared with the comparison, the toner of the present invention has a high OHP transparency, the halftone uniformity and the image sharpness are both good, and no fixing offset occurs.
It is clear that there is low fog and there is no filming on the photoreceptor.

[0387]

According to the present invention, the OHP transparency is high, the halftone uniformity and the image sharpness are good, and
There is no fixing offset, low fog, and
Toner for electrostatic charge image development without filming on the photoconductor,
The toner manufacturing method and the image forming method can be provided.

[Brief description of drawings]

1 is a disperser used to obtain a colorant according to the present invention.

FIG. 2 is a schematic diagram illustrating toner particles having a sea-island structure according to the present invention.

FIG. 3 is a schematic diagram in which toner particles having a sea-island structure according to the present invention are divided by Voronoi polygons.

FIG. 4 is a schematic diagram illustrating toner particles having no corners and toner particles having corners.

FIG. 5 is a configuration cross-sectional view showing an example of the configuration of a fixing device applied to the present invention.

FIG. 6 is a schematic configuration diagram showing an example of an image forming apparatus using a transfer roll applied to the present invention.

FIG. 7 is a schematic configuration diagram showing an example of an image forming apparatus using a transfer belt applied to the present invention.

[Explanation of symbols]

101 screen 102 rotor M stirring chamber 103 Pressurized vacuum attachment 104 Pre-dispersion liquid inlet 105 Dispersion liquid outlet 106 temperature sensor 107 cooling jacket 108 cooling coil 111 dispersion container 112 Stirrer 113 Stirrer shaft 10 photoconductor 11 charger 12 Digital image exposure light 13 Developer 14 Separator 15 Transfer roll 16 bias power supply 17 Cleaning blade 18 Static elimination lamp 19 Paper feed roller 20 Fixer P transfer material Pa, Pb, Pc, Pd image forming unit 1a, 1b, 1c, 1d photoconductor 2a, 2b, 2c, 2d latent image forming section 3a, 3b, 3c, 3d Development section 4a, 4b, 4c, 4d Transfer discharge unit 5a, 5b, 5c, 5d Cleaning section 6a, 6b, 6c, 6d charger 22a, 22b, 22c, 22d Separated static eliminator 23 Fixing device 24 Cleaning device 25 outlet 84 heating body 85 Alumina substrate 86 Resistance material 87 Temperature sensor 88 film 89 Drive roller 90 Driven roller 91 Feeding shaft 92 Winding shaft 93 Unfixed toner image 94 Transfer material 95 Pressure roller 75 Heating member

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kaori Soeda             2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica stock             In the company (72) Inventor Tatsuya Nagase             2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica stock             In the company (72) Inventor Naohiro Hirose             2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica stock             In the company F-term (reference) 2H005 AA15 AB02 AB03 CA21 CA23                       CA30 EA05 EA10                 2H033 AA01 AA09 AA15 AA20 BA11                       BA12 BA25 BA32 BA58 BB06                       BB29 BB33 BB37 BB38 BE03                       CA07 CA30 CA46

Claims (13)

[Claims] 1. A toner for developing an electrostatic charge image, comprising toner particles containing a binder resin and a colorant, the toner particles being formed in a water-based medium, and having a tetrahydrofuran elution content of 40 ppm. ~ 20,000 pp
The chromatic pigment of m is dispersed in an aqueous medium, the resulting dispersion is used as a component of the colorant to form the toner particles, and the volume average particle diameter of the toner particles is 3 0.0 μm to 7.5 μm, and the circularity is 0.9.
A toner for developing an electrostatic charge image, characterized in that the toner content is 45 to 0.985. 2. The chromatic color pigment comprises a divalent metal in an amount of 50 ppm to
10. The composition according to claim 1, wherein the content is 10,000 ppm.
The toner for developing an electrostatic image as described in 1. 3. The toner for developing an electrostatic charge image according to claim 1, wherein the chromatic color pigment is a water wet paste. 4. The area of a Voronoi polygon formed by a perpendicular bisector between the centers of gravity of adjacent islands in the sea-island structure, wherein the binder resin of the toner particles and the colorant constitute a sea-island structure. The average value is 20,000 nm ^{2 to} 120,000 nm ² , and the coefficient of variation of the area of the Voronoi polygon is 25.
% Or less, the toner for developing an electrostatic charge image according to any one of claims 1 to 3, wherein 5. The toner for developing an electrostatic charge image according to claim 1, wherein the chromatic pigment contains a compound represented by the following general formula (1). [Chemical 1] [In the formula, X ₁ , X ₂ , X ₃ , Y ₁ , Y ₂ and Y ₃ are respectively
Hydrogen atom, alkyl group having 1 to 3 carbon atoms, fluoroalkyl group having 1 to 3 carbon atoms, alkoxyl group having 1 to 3 carbon atoms,
Halogen atom, nitro group, sulfo group, alkaline earth metal salt or higher amine salt of sulfo group, N-phenylaminosulfonyl group, carboxyl group, alkaline earth metal salt or higher amine salt of carboxyl group, N-phenylcarbamoyl group , A ureylene group, an iminodicarbonyl group, an alkoxycarbonyl group, —CONHR ₁ (wherein R ₁ is
It represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or a phenyl group. ), —NHCOR ₂ (in the formula, R ₂ represents an alkyl group) or —SO ₂ R ₃ (in the formula, R ₃ is an alkyl group having 1 to 8 carbon atoms). ] 6. The chromatic pigment contains a compound represented by the general formula (1) and a compound represented by the following general formula (2), wherein: The toner for developing an electrostatic image as described in 1. [Chemical 2] [In the formula, X ₁ , X ₂ , X ₃ , Y ₁ , Y ₂ and Y ₃ are respectively
Hydrogen atom, alkyl group having 1 to 3 carbon atoms, fluoroalkyl group having 1 to 3 carbon atoms, alkoxyl group having 1 to 3 carbon atoms,
Halogen atom, nitro group, sulfo group, alkaline earth metal salt or higher amine salt of sulfo group, N-phenylaminosulfonyl group, carboxyl group, alkaline earth metal salt or higher amine salt of carboxyl group, N-phenylcarbamoyl group , A ureylene group, an iminodicarbonyl group, an alkoxycarbonyl group, —CONHR ₁ (wherein R ₁ is
It represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or a phenyl group. ), —NHCOR ₂ (in the formula, R ₂ represents an alkyl group) or —SO ₂ R ₃ (in the formula, R ₃ is an alkyl group having 1 to 8 carbon atoms). ] 7. The electrostatic charge image developing toner according to claim 1, wherein the chromatic pigment contains a compound represented by the following general formula (3). [Chemical 3] [In the formula, R ₂ , R ₃ , R ₄ , and R ₅ are each a hydrogen atom, an alkyl group, an alkoxyl group, a carboxyl group, a hydroxyl group, a sulfo group, a nitro group, a halogen atom, an alkoxycarbonyl group, a carbamoyl group, and a sulfamoyl group. Represents a group, an acyl group, an acylamino group, an alkylthio group, an aryl group, an aryloxy group or the like. ] 8. The toner for developing an electrostatic charge image according to claim 1, wherein the toner contains two kinds of surfactants. 9. In producing the toner for developing an electrostatic charge image according to claim 1, a chromatic pigment having a tetrahydrofuran elution content of 40 ppm to 20,000 ppm is weight averaged in an aqueous medium. Particle size is 30
A method for producing a toner for developing an electrostatic charge image, comprising: a step of preparing toner particles using a dispersion liquid having a particle size of 0 nm or less; and a step of separating the toner particles from an aqueous medium. 10. The chromatic pigment contains 50 pp of a divalent metal.
The toner for developing an electrostatic image according to claim 9, characterized in that the toner contains m to 10,000 ppm. 11. A step of dispersing a binder resin in the presence of an anionic surfactant A to prepare a dispersion A of the binder resin,
A step of dispersing a colorant in the presence of the anionic surfactant B to prepare a dispersion B of the colorant, and mixing the dispersion A and the dispersion B in the presence of the anionic surfactant C, and then adding a salt. Analysis /
The electrostatic charge image according to claim 9 or 10, further comprising a step of fusing, wherein at least one of the anionic surfactants A, B and C has a molecular structure different from those of the other two. Method for producing developing toner. 12. A latent image forming step of forming a latent image on a latent image carrier, a developing step of visualizing the latent image with toner, and a toner image formed on the latent image carrier. An image forming method comprising: a transfer step of transferring the toner image onto the transfer object; and a fixing step of heating and fixing the toner image on the transfer object using a heating member and a pressure member, wherein the toner is 9. The toner for developing an electrostatic image according to any one of item 8, wherein the heating member has an elastic layer. 13. The image forming method according to claim 12, wherein at least one of the heating member and the pressing member is a belt.