JP2003330227A - Toner for developing electrostatic charge image, method for manufacturing toner for developing electrostatic charge image and method for forming image - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner for developing an electrostatic charge image with low fog and favorable transparency for an OHP, a method for manufacturing a toner for developing an electrostatic charge image, and a method for forming an image. <P>SOLUTION: The toner for developing an electrostatic charge image is manufactured in a process of melting resin particles and colorant particles in an aqueous medium. The toner contains at least two kinds of compounds expressed by general formula (1), with the content of the compounds controlled to 1 to 1,000 ppm. <P>COPYRIGHT: (C)2004,JPO

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 an electrostatic charge image developing toner, and an image forming method.

[0002]

2. Description of the Related Art Today, an electrostatic latent image developing method represented by an electrophotographic method is widely used as an image forming method for printers, copying machines, facsimiles and the like.

The reason for this is that it is a method with a high degree of perfection in which a high-quality image can be stably obtained at a high speed, but some problems still remain.

For example, in the conventional toner prepared by the pulverization method, the material dispersed in the toner is nonuniformly present on the fracture surface, the surface properties of the toner are difficult to be constant, and variations occur in the transfer process. However, there is a problem that the color reproducibility as a color image is deteriorated.

On the other hand, the electrostatic latent image developing toner is desired to have a small particle size from the viewpoint of high image quality. As a method for producing a toner having a small particle diameter, development of a polymerization toner has been active in recent years. In this polymerization method, resin particles and colorant particles are optionally associated with or salted out, aggregated, and fused to prepare an amorphous toner, or a radically polymerizable monomer and a colorant are dispersed. Then, there is a method in which droplets are dispersed in an aqueous medium or the like so as to have a desired toner particle diameter, and suspension polymerization is performed.

However, since the toner particles produced by applying the suspension polymerization method can form a spherical toner having a uniform surface property, the toner particles have high uniformity but have a spherical shape. Therefore, the adhesiveness to the latent image carrier is increased, and there is a problem that the transferability is reduced.

In order to address such a problem, resin particles polymerized in an aqueous medium containing a surfactant are coagulant in a concentration not lower than the critical coagulation concentration of the resin particles, and an organic solvent which infinitely dissolves in water. Disclosed is a non-spherical particle (see, for example, Patent Document 1), which is characterized in that the non-spherical particle is produced by being treated with.

In the above technique, by using a divalent or trivalent metal salt as the aggregating agent, an image having excellent shape uniformity and charge amount uniformity and high sharpness can be obtained. Due to the presence of the trivalent metal salt, the Kraft point of the surfactant is increased, and a hardly water-soluble precipitate is formed. These deposits are present in a state of adhering to the toner even after the colored particles, that is, the toner is separated from the aqueous medium, and there are problems that the fine line reproducibility is likely to be deteriorated and that characters are likely to be crushed.

Further, as an emulsifier for emulsion polymerization, conventionally,
Alkylbenzene sulphate is commonly used,
During the reaction in an aqueous medium, a by-product which is hardly soluble with other metal elements and the like is produced and mixed into the toner to cause fog on the image, OHP transparency and other toner performance. There are problems such as adversely affecting

[0010]

[Patent Document 1] Japanese Patent Application Laid-Open No. 11-194540

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrostatic charge image developing toner having a low fog and good OHP transparency, a method for producing the electrostatic charge image developing toner, and an image forming method. It is to be.

[0012]

The above objects of the present invention have been achieved by the following constitutions 1 to 5.

1. A toner for developing an electrostatic charge image produced through a step of fusing resin particles and colorant particles in an aqueous medium, containing at least two compounds represented by the general formula (1), and Compound content is 1pp
A toner for developing an electrostatic charge image, characterized in that it is from m to 1000 ppm.

2. 250 ppm to 20 of polyvalent metal element
The toner for developing an electrostatic charge image as described in 1 above, which contains 000 ppm.

3. In producing the electrostatic image developing toner described in 1 or 2, there is provided a step of polymerizing a polymerizable monomer in an aqueous medium to produce a resin. Production method.

4. In producing the electrostatic image developing toner described in 1 or 2, toner particles are produced through a step of aggregating and fusing resin particles in an aqueous medium, Toner manufacturing method.

5. Forming an electrostatic charge image on the electrostatic charge image carrier, developing the electrostatic charge image with a developer containing a toner for developing an electrostatic charge image to form a toner image, and transferring the toner image onto a transfer body An image forming method including the step of using the electrostatic charge image developing toner according to 1 or 2 as the electrostatic charge image developing toner.

The present invention will be described in detail below. The present inventors have made various studies on the problems described above, and as a result, claim 1
In the toner for developing an electrostatic charge image produced through the step of fusing resin particles and colorant particles in an aqueous medium as described in 1., the compound represented by the general formula (1) (surfactant It is also possible to obtain a toner for developing an electrostatic charge image with improved image fog and OHP transmissive toner performance.

The reason for this is that by limiting the ratio of the number of carbon atoms of the alkyl in the alkylbenzene sulfonate to a specific range, it was possible to successfully suppress the hardly soluble by-products with other metal elements and the like. As a fog on the image,
It is considered that the effect of improving the OHP permeability was obtained.

<< Compound Represented by General Formula (1) (Surfactant) >> The compound represented by the general formula (1) is a dispersion liquid of resin particles relating to the toner for developing an electrostatic image of the present invention. It is used in the step of preparing and fusing the resin particles and the colorant particles, and is characterized in that they are present in the toner even after the final toner formation.

The compound represented by the general formula (1) (also referred to as a surfactant) will be described. In the general formula (1), R ₁ represents an aliphatic hydrocarbon group, but from the viewpoint of obtaining the effects described in the present invention, an aliphatic hydrocarbon group having 6 to 22 carbon atoms is preferable, and more preferably, 8 carbons
It is an aliphatic hydrocarbon group having 20 carbon atoms, and particularly preferably an aliphatic hydrocarbon group having 9 to 16 carbon atoms.

Examples of the aliphatic hydrocarbon 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, n-dodecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, alkyl group such as n-docosadecyl group, decenyl group, dodecenyl group, tridecenyl group,
Pentadecenyl group, 5- (3-pentenyl) -3,6
8-decatriene-1-ynyl group, 6- (1,3-pentadienyl) -2,4,7-docodecatriene-9-ynyl group, 6- (1-penten-3-ynyl) -2,4
Unsaturated aliphatic hydrocarbon group such as 7,9-undecatetraenyl group (alkenyl group, alkadienyl group, alkatrienyl group and alkapolyenyl group); Cyclic aliphatic hydrocarbon such as octylcyclohexyl group and nonylcyclohexyl group Groups and the like. These aliphatic hydrocarbon groups may be linear or branched.

Examples of the alkyl group represented by R ₂ include methyl group, ethyl group, propyl group, iso-propyl group, tert-butyl group, pentyl group, hexyl group,
Examples thereof include an octyl group, a dodecyl group, a tridecyl group, a tetradecyl group, and a pentadecyl group.

Examples of the alkenyl group represented by R ₂ include a vinyl group, an allyl group, a prenyl group and an octenyl group.

Examples of the alkynyl group represented by R ₂ include a propargyl group, an ethynyl group and a trimethylsilylethynyl group.

Examples of the aryl group represented by R ₂ include phenyl group, naphthyl group, p-tolyl group, m-chlorophenyl group, o-hexadecanoylaminophenyl group and the like.

The alkoxyl group represented by R ₂ is
For example, methoxy group, ethoxy group, propyloxy group,
Examples thereof include a tert-butoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a dodecyloxy group, a phenyloxy group and a naphthyloxy group.

The alkylthio group represented by R ₂ is
Examples thereof include a methylthio group, an ethylthio group, a propylthio group, a pentylthio group, a hexylthio group, an octylthio group, a dodecylthio group, a cyclopentylthio group and a cyclohexylthio group.

The arylthio group represented by R ₂ is
Examples thereof include a phenylthio group and a naphthylthio group.

Examples of the heterocyclic group represented by R ₂ include pyridyl group, thiazolyl group, oxazolyl group, imidazolyl group, furyl group, pyrrolyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, selenazolyl group, sulforanyl group, Examples thereof include a piperidinyl group, a pyrazolyl group and a tetrazolyl group.

The heterocyclic oxy group represented by R ₂ is
For example, 1-phenyltetrazole-5-oxy group, 2
-Tetrahydropyranyloxy group, pyridyloxy group,
Examples thereof include a thiazolyloxy group, an oxazolyloxy group and an imidazolyloxy group.

The group represented by R ₂ may further have a substituent, but in the present invention, it is preferable that at least one sulfo group or a salt of the sulfo group has a substituent.
More preferably, it has a salt of the sulfo group as a substituent.

Examples of the salt of the sulfo group include sodium salt, potassium salt, lithium salt, calcium salt, ammonium group and the like.

In the group represented by SO ₃ M, monovalent metal elements represented by M include sodium, potassium,
Examples include lithium. Among them, sodium is preferably used.

In the group represented by SO ₃ M, the divalent metal element represented by M includes beryllium, magnesium, calcium and the like. Among them, calcium is preferably used.

In the compound (surfactant) represented by the general formula (1) according to the present invention, the group represented by R ₂ or S
When the group represented by O ₃ M forms a salt with a divalent metal element, the group represented by R ₂ and SO ₃ M may form an intramolecular salt. An intermolecular salt may be formed with another molecule represented by the general formula (1).

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

Compound (1): (n) C ₆ H _13- (C ₆ H
₄₎ p-SO ₃ Na Compound (2): (n) C 8 H 17 - (C 6 H 4) p-SO 3
Na compound (3): (t) C 8 H 17 - (C 6 H 4) p-SO 3
Na compound (4): (n) C 9 H 19 - (C 6 H 4) p-SO 3
Na compound (5): (n) C 12 H 25 - (C 6 H 4) p-SO
₃ Na Compound (6): (t) C 12 H 25 - (C 6 H 4) p-SO
₃ Na Compound (7): (n) C 18 H 37 - (C 6 H 4) p-SO
₃ Na Compound (8): (t) C 18 H 37 - (C 6 H 4) p-SO
₃ Na Compound (9): (n) C 22 H 45 - (C 6 H 4) p-SO
₃ Na Compound _{(10) :( i) C 6} H 13 - (C 6 H 4) p-SO 3
In Na above-exemplified _{compounds, - (C 6 H 4)} p- represents a para-phenylene group.

[0039]

[Chemical 2]

The compounds (1) to (12) are mainly composed of the compounds of the above structural formulas (50% by mass in the mixture).
It is a mixture of compounds in which the number of carbon atoms of the alkyl group is different, respectively. In Table 1, the number of carbon atoms remaining in the toner is 6 to 6 after the toner is produced by using the above compound.
The content of all compounds represented by the general formula (1) having 22 was described. Further, in the above compound, the position of the substituent of the phenylene group is p, that is, the para-substituted product.

The toner for developing an electrostatic charge image of the present invention is represented by at least two kinds of the general formula (1) from the viewpoints of preventing fog of the toner under high temperature and high quality conditions and improving the transparency of an OHP image. The compound represented by the general formula (1) is present in the toner as a mixture, and the number of carbon atoms of the hydrocarbon group represented by R in the mixture. It is essential in the present invention that the proportion of the compound having a range of 6 to 22 is 50% by mass to 90% by mass.

Regarding the above-mentioned proportions, preferably
It is in the range of 60% by mass to 70% by mass, and more preferably in the range of 65% by mass to 70% by mass.

The content of the compound represented by the general formula (1) in the electrostatic image developing toner of the present invention is essential to be 1 ppm to 1000 ppm, preferably 5 ppm to It is 500 ppm, and more preferably 7 ppm to 100 ppm.

As means for adjusting the content of the compound represented by the general formula (1) in the toner for developing an electrostatic image of the present invention to the content described above, the preparation of (a) latex. , The amount of the colorant used at the time of dispersion, (b) the preparation of the washing conditions at the time of producing the colored particles, (c) after the production of the colored particles,
It can be adjusted by selecting an appropriate one from among things such as post-addition after the preparation of the toner or the preparation of the developer.

By incorporating the compound represented by the general formula (1) (also referred to as a surfactant) in the toner of the present invention within the above range, the effect described in the present invention can be obtained. However, the electrostatic property of the toner for developing an electrostatic image of the present invention is not affected by the influence of the environment and is always uniform, and
It is also possible to obtain the secondary effect of stably imparting and maintaining.

The method for measuring the content of the surfactant represented by the general formula (1) described above in the toner for developing an electrostatic image of the present invention is as follows.

1 g of the toner is dissolved in 50 ml of chloroform, and the surfactant is 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 structure of the surfactant represented by the general formula (1) was determined by analyzing the above extract using ¹ H-NMR.

In the present invention, a metal salt is preferably used as an aggregating agent in the step of salting out, aggregating and fusing resin particles from a dispersion liquid of resin particles prepared in an aqueous medium, and more preferably 2 The use of a monovalent or trivalent metal salt as a flocculant. The reason is that the divalent or trivalent metal salt has a smaller critical aggregation concentration (coagulation value or coagulation point) than the monovalent metal salt.

The metal salt used as the aggregating agent or the aggregation stopping agent according to the present invention will be described.

Examples of the metal salt include monovalent metal salts such as salts of alkali metals such as sodium, potassium and lithium, and 2
Valent metals, for example, salts of alkaline earth metals such as calcium and magnesium, divalent metal salts such as manganese and copper, iron,
Examples thereof include trivalent metal salts such as aluminum. Specific examples of these metal salts are shown below.

Specific examples of the metal salt of a monovalent metal include sodium chloride, potassium chloride, lithium chloride and the like. Examples of the metal salt of a divalent metal include magnesium chloride, calcium chloride, calcium nitrate, zinc chloride, copper sulfate, magnesium sulfate, manganese sulfate and the like.
Examples of the trivalent metal salt include aluminum chloride and iron chloride. These are appropriately selected according to the purpose.

The above-mentioned critical coagulation concentration is an index relating to the stability of the dispersion in the aqueous dispersion, to which a coagulant is added,
The concentration at the point where aggregation occurs is shown. This critical coagulation concentration greatly changes depending on the latex itself and the dispersant.
For example, Seizo Okamura et al., Polymer Chemistry 17,601 (19)
60) etc., and its value can be known by following these descriptions.

As another method, a desired salt is added to the target particle dispersion liquid at various concentrations, and ζ of the dispersion liquid is added.
It is also possible to measure the potential and set the salt concentration at the point where the ζ potential starts to change as the critical aggregation concentration.

The polymer fine particle dispersion is treated with the above-described metal salt according to the present invention so as to have a concentration higher than the critical aggregation concentration. At this time, as a matter of course, whether the metal salt is directly added or added 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.

The concentration of the metal salt used as the aggregating agent is
It may be added at a critical coagulation concentration or higher, but preferably 1.2 times or more, more preferably 1.5 times or more the critical coagulation concentration.

It should be noted that composite resin particles (when the particles have a multi-layered structure or when the particles contain other constituent components such as additives, etc. are called composite resin particles) and colorant particles are dispersed. The temperature of the dispersion when adding the aggregating agent to the dispersion is preferably not higher than the glass transition temperature (Tg) of the composite resin particles, and specifically in the range of 5 to 55 ° C. The temperature is preferably set to 10 ° C to 45 ° C.

The temperature of the dispersion when adding the coagulant is
When the glass transition temperature (Tg) of the composite resin particles is equal to or higher than the glass transition temperature (Tg), it is difficult to control the particle size, and giant particles are easily generated.

In the salting-out, aggregating, and fusing step, the temperature of the dispersion liquid in which the composite resin particles and the colorant particles are dispersed is the glass transition temperature (T
g) At the following times, the flocculant is added while stirring the dispersion, and then the heating of the dispersion is immediately started,
The temperature is preferably equal to or higher than the glass transition temperature (Tg) of the composite resin particles.

Further, in the present invention, after the resin particles and the colorant are salted out, aggregated and fused in an aqueous medium to obtain colored particles (in the present invention, referred to as toner particles), the toner particles are 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 fusing steps, that is, a surfactant solution, was mixed with an actually used amount of the 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.

From the viewpoint of suppressing excessive charging of toner particles and imparting uniform charging properties, the toner for developing an electrostatic charge image of the present invention is particularly suitable for stabilizing and maintaining the charging properties with respect to the environment. 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.

The amount of residual metal ions in the toner was measured by using a fluorescent X-ray analyzer "System 3270" (manufactured by Rigaku Denki Kogyo Co., Ltd.) to determine the metal species of the metal salt used as the aggregating agent (for example, It can be determined by measuring the intensity of fluorescent X-rays emitted from calcium (derived from calcium chloride, etc.). 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, and the content ratio of the aggregating agent metal salt (mass p
pm) and the fluorescent X-ray intensity (peak intensity) from the metal species of the metal salt are measured (calibration curve). Next, the toner (sample) whose content ratio of the coagulant metal salt is to be measured is similarly pelletized, and fluorescence X from the metal species of the coagulant metal salt is collected.
By measuring the line strength, the content ratio, that is, the “residual amount of metal ions in the toner” can be obtained.

A method for producing the electrostatic image developing toner of the present invention will be described. The toner of the present invention forms composite resin particles in the absence of a colorant, adds a dispersion of colorant particles to a dispersion of the composite resin particles, salts out the composite resin particles and the colorant particles, It is prepared by aggregating and 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 characteristics of the obtained toner particles are uniform and the distribution of the amount of charge is sharp, so that an image having excellent sharpness can be formed for a long period of time.

The "composite resin particles" constituting the toner of the present invention are composed of a resin having a molecular weight and / or a composition different from that of the resin forming the core particles so as to cover the surface of the core particles made of the resin. Alternatively, it means a resin particle having a multilayer structure in which two or more coating layers are formed.

The "central part (nucleus)" of the composite resin particles means "nucleus particles" constituting the composite resin particles.

The "outer layer (shell)" of the composite resin particle means the outermost layer of "one or more coating layers" constituting the composite resin particle.

The "intermediate layer" of the composite resin particles means a coating layer formed between the central portion (nucleus) and the outer layer (shell).

The molecular weight distribution of the composite resin particles is not monodisperse, and the composite resin particles usually have a molecular weight gradient from the central part (nucleus) to the outer layer (shell).

In the present invention, it is preferable to use the "multi-stage polymerization method" to obtain the composite resin particles, from the viewpoint of controlling the molecular weight distribution, that is, from the viewpoint of securing the fixing strength and the offset resistance. In the present invention, the “multi-stage polymerization method” for obtaining the composite resin particles means that a single amount is present in the presence of the resin particles (n) obtained by polymerizing the monomer (n) (nth stage). The polymer (n + 1) is subjected to a polymerization treatment (n + 1th stage), and a polymer of the monomer (n + 1) (dispersed with the constituent resin of the resin particles (n) and / or composition is formed on the surface of the resin particles (n). A method of forming a coating layer (n + 1) made of different resins will be shown.

Here, when the resin particles (n) are core particles (n = 1), the "two-stage polymerization method" is applied, and when the resin particles (n) are composite resin particles (n ≧ 2). In other words, it is a multi-step polymerization method of three or more steps.

A plurality of resins having different compositions and / or molecular weights are present in the composite resin particles obtained by the multistage polymerization method. Therefore, the toner obtained by salting out, aggregating, and fusing the composite resin particles and the colorant particles has extremely small variations in composition, molecular weight, and surface characteristics among the toner particles.

Such a toner having a uniform composition, molecular weight, and surface characteristics among the toner particles has good adhesiveness (high fixing strength) to an image support in an image forming method including a fixing step by a contact heating system. It is possible to improve the anti-offset property and the anti-wrapping property while maintaining the above value), and it is possible to obtain an image having an appropriate gloss.

An example of the method for producing the toner for developing an electrostatic image according to the present invention will be specifically described. (1) The release agent and / or the crystalline polyester is a region other than the outermost layer (central portion or intermediate layer). Multi-stage polymerization step (I) for obtaining composite resin particles prepared so as to be contained in 1., (2) salting-out, aggregating and fusing composite resin particles and colorant particles to obtain toner particles Step (II) of aggregating and fusing, (3) Toner particles filtered from the dispersion system of toner particles to remove a surfactant and the like from the toner particles, a washing step, (4) washing-treated toner The method comprises a drying step of drying the particles and (5) a step of adding an external additive to the dried toner particles.

Each step will be described below. << Multistage Polymerization Step (I) >> The multistage polymerization step (I) is performed by a multistage polymerization method in which a coating layer (n + 1) made of a polymer of a monomer (n + 1) is formed on the surface of the resin particles (n). This is a step of producing resin particles. Where the manufacturing stability,
From the viewpoint of the crush strength of the obtained toner, it is preferable to employ a multi-stage polymerization method of three or more stages.

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.

<< Explanation of Two-Step Polymerization Method >> The two-step polymerization method is a central part (nucleus) formed from a high molecular weight resin containing a release agent.
And a method for producing composite resin particles composed of an outer layer (shell) formed of a low molecular weight resin. That is, the composite resin particles obtained by the two-step polymerization method are composed of the core and one coating layer.

This method will be described in detail. First, a monomer solution obtained by dissolving a releasing agent in a monomer (H) is dispersed in an aqueous medium (aqueous solution of a surfactant) as oil droplets. Then, by subjecting this system to a polymerization treatment (first stage polymerization),
A dispersion liquid of high molecular weight resin particles (H) containing a release agent is prepared.

Then, to the dispersion liquid of the resin particles (H),
Polymerization initiator and monomer (L) for obtaining low molecular weight resin
Is added, and the monomer (L) is subjected to a polymerization treatment (second-stage polymerization) in the presence of the resin particles (H), so that a resin having a low molecular weight (mono) is added to the surface of the resin particles (H). A coating layer (L) made of a polymer of the polymer (L) is formed.

<< Explanation of Three-Step Polymerization Method >> In the three-step polymerization method, a central part (nucleus) formed of a high molecular weight resin, an intermediate layer containing a release agent, and an outer layer formed of a low molecular weight resin ( shell)
And a method for producing composite resin particles composed of That is, the composite resin particles obtained by the three-step polymerization method are composed of a core and two coating layers.

This method will be described in detail. First, a dispersion of resin particles (H) obtained by a polymerization treatment (first stage polymerization) according to a conventional method is treated with an aqueous medium (aqueous solution of a surfactant). And a dispersion of the monomer solution obtained by dissolving the release agent in the monomer (M) in the aqueous medium to disperse the oil droplets, and then the system is subjected to a polymerization treatment (second-stage polymerization). Thus, a coating layer (M) (intermediate layer) made of a resin (polymer of monomer (M)) containing a release agent is formed on the surface of the resin particles (H) (core particles). A dispersion liquid of the following composite resin particles [high molecular weight resin (H) -intermediate molecular weight resin (M)] is prepared.

Then, a polymerization initiator and a monomer (L) for obtaining a low molecular weight resin are added to the obtained dispersion liquid of the composite resin particles, and the monomer is added in the presence of the composite resin particles. By polymerizing (L) (third stage polymerization), a low molecular weight resin (monomer (L) is formed on the surface of the composite resin particles.
To form a coating layer (L).

In this three-stage polymerization method, resin particles (H)
When the coating layer (M) is formed on the surface of the resin, the dispersion liquid of the resin particles (H) is added to the aqueous medium (aqueous solution of the surfactant), and a release agent is added to the aqueous medium in a single amount. A method of polymerizing the system (second-stage polymerization) after dispersing a monomer solution dissolved in the body (M) into oil droplets to disperse the release agent finely and uniformly be able to.

As for the addition treatment of the dispersion liquid of the resin particles (H) and the oil droplet dispersion treatment of the monomer solution, any of them may be performed in advance as described below, or they may be performed simultaneously. May be.

(A) When the intermediate layer constituting the composite resin particles is formed, the resin particles to be the central portion (nucleus) of the composite resin particles are added to the aqueous solution of the surfactant, and then the aqueous solution of the surfactant is added. A mode in which a monomer composition containing a release agent / crystalline polyester is dispersed and this system is subjected to a polymerization treatment, and (b) a release agent / crystallinity when forming an intermediate layer constituting composite resin particles. A monomer composition containing polyester is dispersed in an aqueous solution of a surfactant, and then resin particles to be the central part (nucleus) of the composite resin particles are added to the aqueous solution to polymerize this system. Aspect, (c) When forming the intermediate layer constituting the composite resin particles, at the same time as adding the resin particles to be the central portion (nucleus) of the composite resin particles to the aqueous solution of the surfactant,
A mode in which a monomer composition containing a release agent / crystalline polyester is dispersed in the aqueous solution and the system is subjected to a polymerization treatment is included.

As a method for forming resin particles (core particles) or a coating layer (intermediate layer) containing a release agent, the release agent is dissolved in a monomer and the resulting monomer solution is added to an aqueous medium. A method of obtaining latex particles by dispersing oil droplets in the above and polymerizing this system can be adopted.

Here, the "aqueous medium" means water 50 to 10
A medium composed of 0 mass% and a water-soluble organic solvent of 0 to 50 mass%. Examples of the water-soluble organic solvent include methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, and tetrahydrofuran, and alcohol-based organic solvents that do not dissolve the obtained resin are preferable.

A polymerization method suitable for forming resin particles or a coating layer containing a release agent is as follows. An aqueous medium prepared by dissolving a surfactant at a concentration below the critical micelle concentration is used.
A monomer solution prepared by dissolving a release agent in a monomer is dispersed into oil droplets by using mechanical energy to prepare a dispersion liquid, and a water-soluble polymerization initiator is added to the obtained dispersion liquid. Then, a method of radical polymerization in oil droplets (hereinafter referred to as "mini-emulsion method") can be mentioned. Instead of adding the water-soluble polymerization initiator, or while adding the water-soluble polymerization initiator, an oil-soluble polymerization initiator may be added to the monomer solution.

According to the mini-emulsion method of mechanically forming oil droplets, unlike the usual emulsion polymerization method, the releasing agent dissolved in the oil phase is not released and the formed resin particles or A sufficient amount of release agent can be introduced into the coating layer.

The disperser for dispersing oil droplets by mechanical energy is not particularly limited, and a stirring device "CLEARMIX" (MEAR TECHNIQUE) equipped with a rotor rotating at high speed is used. (Manufactured by K.K.), an ultrasonic disperser, a mechanical homogenizer, Manton-Gaulin, and a pressure homogenizer. The dispersed particle size is 10 to 1
000 nm, preferably 50 to 1000 nm, more preferably 30 to 300 nm.

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

The particle size of the composite resin particles obtained in this polymerization step (I) is determined by the electrophoresis light scattering photometer "ELS-80".
0 "(manufactured by Otsuka Electronics Co., Ltd.) is preferably in the range of 10 to 1000 nm as the weight average particle diameter.

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

<< Step (II) of salting out, aggregating, and fusing >> The step (II) of salting out, aggregating, and fusing includes the composite resin particles obtained in the multi-step polymerization step (I) and colorant particles. Is a step of obtaining amorphous (non-spherical) toner particles by salting out, aggregating, and fusing (simultaneously causing salting out and fusing).

In the step (II) of salting out, aggregating, and fusing, internal additive particles such as a charge control agent (having a number average primary particle size of 10 to 1 are used together with the composite resin particles and the colorant particles.
Fine particles of about 000 nm) may be salted out, aggregated, and fused.

The colorant particles may be surface-modified. Here, as the surface modifier, a conventionally known one can be used.

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

As the surfactant, the same surfactant as used in the multistage polymerization step (I) can be used.

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

In order to salt out, aggregate and fuse the composite resin particles and the colorant particles, a flocculant 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. At the same time, it is preferable to heat the dispersion liquid to the glass transition temperature (Tg) or higher of the composite resin particles.

More preferably, the aggregation stopper is used at the stage when the composite resin particles have reached a desired particle diameter by the aggregating agent. As the aggregation stopper, monovalent metal salts, especially sodium chloride, are preferably used.

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

Examples of the "aggregating agent" used for salting out, aggregating and fusing include the above-mentioned alkali metal salts and alkaline earth metal salts.

Salting-out and agglomeration according to the present invention will be described. In the present invention, "salting out, aggregating, and fusing" means
Salting out (aggregation of particles) and fusion (disappearance of interface between particles) occur at the same time, or the action of causing salting out and fusion at the same time.

In order to carry out salting out and fusion at the same time,
Glass transition temperature (Tg) of resin constituting composite resin particles
It is preferable to aggregate the particles (composite resin particles, colorant particles) under the above temperature conditions.

The toner for developing an electrostatic image of the present invention forms composite resin particles in the absence of a colorant, and the dispersion liquid of the colorant particles is added to the dispersion liquid of the composite resin particles to obtain the composite resin particles. It is preferably prepared by salting out, aggregating, and fusing with the colorant particles.

As described above, 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 obtained toner particles have uniform surface characteristics and a sharp charge amount distribution, 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 anti-offset property and the wrapping prevention property, and it is possible to obtain an image having an appropriate gloss.

The release agent used in the toner of the present invention will be described. The content of the release agent constituting the toner for developing an electrostatic image of the present invention is usually 1 to 30% by mass, preferably 2 to 20% by mass, more preferably 3 to 1%.
It is set to 5% by mass.

As the releasing agent, low molecular weight polypropylene (number average molecular weight = 1500 to 9000), low molecular weight polyethylene or the like may be added, and the preferable releasing agent is preferably an ester compound represented by the following general formula.

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

R ₁ and R ₂ represent a hydrocarbon group which may have a substituent. R _1: a carbon number = 1-40, preferably 1-20, more preferably 2 to 5 R _2: the number of carbon atoms = 1-40, preferably 16-30, more preferably to 18 to 26 below, the general formula Specific examples of the ester compound represented by are shown below, but the present invention is not limited thereto.

[0119]

[Chemical 3]

[0120]

[Chemical 4]

The amount of the releasing agent and the fixing improving agent represented by the general formula to be added is 1% by mass to 30% by mass, preferably 2% by mass to 20% by mass, based on the whole toner for developing an electrostatic image. , And more preferably 3% by mass to 15% by mass.

The preferable molecular weight, molecular weight range, peak molecular weight, etc. of the resin component constituting the electrostatic image developing toner of the present invention will be described.

The toner of the present invention has a peak or shoulder of 100,000 to 1,000,000, and 1,
000 to 50,000, more preferably 100,000 to 1.00 peaks or shoulders.
20,000, 25,000-150,000, 1,
More preferably, it exists in the range of 000 to 50,000.

The molecular weight of the resin of the toner is 100,000.
A high molecular weight component having a peak or shoulder in the region of 1,000,000 to 1,000 to 50,
A resin containing at least both low molecular weight components having a peak or shoulder in a region of less than 000 is preferable. More preferably, the peak molecular weight is 15,
It is to use an intermediate molecular weight resin having a peak or a shoulder in the range of 000 to 100,000.

The molecular weight is measured by GPC (gel permeation chromatography) using THF (tetrahydrofuran) as a column solvent.

Specifically, 1 mg of the measurement sample was used for T
1 ml of HF is added, and the mixture is stirred at room temperature using a magnetic stirrer to sufficiently dissolve it. Then, after being treated with a membrane filter having a pore size of 0.45 to 0.50 μm, it is injected into GPC. The measurement conditions of GPC are as follows: stabilize the column at 40 ° C, and add THF at 1 m / min.
at a flow rate of 1 l and a sample with a concentration of 1 mg / ml is about 100
Inject μl and measure. As the column, it is preferable to use a commercially available polystyrene gel column in combination. For example, Shodex GPC manufactured by Showa Denko KK
KF-801, 802, 803, 804, 805, 80
Combination of 6,807 and TSKgelG1 manufactured by Tosoh Corporation
000H, G2000H, G3000H, G4000
H, G5000H, G6000H, G7000H, TS
A combination of K guard columns and the like can be mentioned.

A refractive index detector (IR detector) or a UV detector is preferably used as the detector. 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. It is preferable to use about 10 points as polystyrene for preparing the calibration curve.

The filtration / washing process relating to the production of the electrostatic image developing toner of the present invention will be described.

In this filtering / washing step, a filtering treatment for filtering the toner particles from the dispersion system of the toner particles obtained in the above step, and the filtered toner particles (cake-like aggregate)
A cleaning process is performed to remove adhering substances such as a surfactant and an aggregating agent.

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 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.

If the dried toner particles are aggregated by a weak attraction force between the particles, the aggregate may be crushed. Here, as the crushing treatment device, a mechanical crushing device such as a jet mill, a Henschel mixer, a coffee mill, a food processor or the like can be used.

The polymerizable monomer according to the present invention will be described. (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, for example:
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 acrylic monomer, acrylic acid,
Methacrylic acid, methyl acrylate, ethyl acrylate,
Butyl acrylate, 2-ethylhexyl acrylate,
Cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, γ-aminoacrylate propyl, stearyl methacrylate, methacrylic Examples thereof include dimethylaminoethyl acid salt and diethylaminoethyl methacrylate.

Examples of vinyl ester-based monomers include vinyl acetate, vinyl propionate, vinyl benzoate and the like.

Examples of the vinyl ether type monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether and the like.

Examples of the monoolefin type monomer include ethylene, propylene, isobutylene, 1-butene, 1-pentene, 4-methyl-1-pentene and the like.

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. As the crosslinkable monomer, divinylbenzene,
Divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate,
Examples thereof include those having two or more unsaturated bonds such as 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) sulfone. An α, β-ethylenically unsaturated compound having a group (—SO ₃ H) can be mentioned.

Examples of the α, β-ethylenically unsaturated compound having a —COO group (a) include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, and monobutyl maleate. Examples thereof include esters, maleic acid monooctyl esters, and metal salts thereof such as Na and Zn.

(B) Examples of the α, β-ethylenically unsaturated compound having a sulfo group (--SO ₃ H group) are sulfonated styrene, its Na salt, allylsulfosuccinic acid, octyl allylsulfosuccinate, and its Na salt. Etc. can be mentioned.

The initiator (also referred to as a polymerization initiator) used for the polymerization of the polymerizable monomer according to the present invention will be described.

The polymerization initiator used in the present invention can be appropriately used if it is water-soluble. For example, persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds (4,4′-azobis-4-cyanovaleric acid and salts thereof,
2,2'-azobis (2-amidinopropane) salt, etc.),
Examples thereof include peroxide compounds such as hydrogen peroxide and benzoyl peroxide.

Further, the above-mentioned polymerization initiator can be used as a redox type initiator in combination with a reducing agent, if necessary. By using the redox type initiator, the polymerization activity can be increased, the polymerization temperature can be lowered, and further shortening of the polymerization time can be expected.

The polymerization temperature may be selected at any temperature as long as it is at least the minimum radical generation temperature of the polymerization initiator, but for example, a range of 50 ° C. to 80 ° C. is used. It is also possible to polymerize at room temperature or a temperature close to it by using a combination of a polymerization initiator which starts at room temperature, for example, hydrogen peroxide-reducing agent (ascorbic acid etc.).

The chain transfer agent used in the present invention will be described. In the present invention, for the purpose of adjusting the molecular weight of the resin particles produced by polymerization of the polymerizable monomer,
Conventionally known and commonly used chain transfer agents can be used.

The chain transfer agent is not particularly limited, but a compound having a mercapto group is particularly preferably used because a toner having a sharp molecular weight distribution can be obtained and the storage stability, fixing strength and offset resistance are excellent. For example, octyl mercaptan, dodecyl mercaptan, t
A compound having a mercapto group such as ert-dodecyl mercaptan is used.

Preferred examples include ethyl thioglycolate, propyl thioglycolate, butyl thioglycolate, t-butyl thioglycolate,
2-ethylhexyl thioglycolate, octyl thioglycolate, decyl thioglycolate, dodecyl thioglycolate, thioglycolic acid ester of ethylene glycol, thioglycolic acid ester of neopentyl glycol, thioglycolic acid ester of pentaerythritol, etc. Can be done.

Among them, n-octyl-3-mercaptopropionic acid ester is preferably used from the viewpoint of suppressing odor during toner heat fixing.

The colorant according to the present invention will be described. The colorant relating to the toner for developing an electrostatic image of the present invention is, from the viewpoint of improving the uniformity of charging of the toner, salting out with the resin particles during the production of the toner, salting out, aggregation and fusion of the above-mentioned composite resin particles. It is preferable that the toner particles are aggregated, fused, and contained in the toner particles.

Examples of the colorant (colorant particles used for salting out, aggregation, and fusion with the composite resin particles) constituting the toner of the present invention 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. 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 predetermined magnetic characteristics, 20 to 1 is included in the toner.
It is preferable to add 20% by mass.

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

As the magenta or red pigment,
C. 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. I. Pigment Red 15, C.I. I. Pigment Red 16,
C. 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. Pigment Red 144, C.I. I. Pigment Red 149, C.I. I. Pigment Red 166, C.I.
I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 222 and the like.

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. 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 94, C.I. I.
Pigment Yellow 138, C.I. I. Pigment Yellow 180, C.I. I. Pigment Yellow 185, C.I.
I. Pigment Yellow 155, C.I. I. Pigment Yellow 156 and the like.

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

As the dye, C.I. I. Solvent Red 1, 49, 52, 58, 63, 111,
122, C.I. I. Solvent Yellow 19, 44,
77, 79, 81, 82, 93, 98, 103, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93,
Id. 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 the pigment added is 2 to 20% by mass, preferably 3 to 15% by mass, based on the polymer.

The colorant (colorant particles) constituting the toner for developing an electrostatic image of the present invention may be surface-modified.
Here, 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 silane coupling agents include alkoxysilanes such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane and diphenyldimethoxysilane, siloxanes such as hexamethyldisiloxane, γ-chloropropyltrimethoxysilane and vinyl. Trichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,
γ-ureidopropyltriethoxysilane and the like can be mentioned.

Examples of titanium coupling agents include:
TTS, 9S, 38S, 41B, 46B, 5 sold under the trade name "Planeact" manufactured by Ajinomoto Co., Inc.
5, 138S, 238S, etc., a commercial product A- manufactured by Nippon Soda Co., Ltd.
1, B-1, TOT, TST, TAA, TAT, TL
A, TOG, TBSTA, A-10, TBT, B-2,
B-4, B-7, B-10, TBSTA-400, TT
S, TOA-30, TSDMA, TTAB, TTOP and the like can be mentioned.

Examples of the aluminum coupling agent include "Planeact AL-M" manufactured by Ajinomoto Co., Inc., and the like.

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.

Examples of the surface modification method of the colorant particles include a method of adding a surface modifier to the dispersion liquid of the colorant particles and heating the system to react.

The surface-modified colorant particles are collected by filtration, washed with the same solvent and filtered, and then dried.

The toner particles constituting the toner of the present invention may contain an internal additive other than the release agent, such as a charge control agent.

The charge control agent contained in the toner particles includes a nigrosine dye, a metal salt of naphthenic acid or a higher fatty acid, an alkoxylated amine, a quaternary ammonium salt compound, an azo metal complex, a salicylic acid metal salt or a salt thereof. Examples thereof include metal complexes.

The external additive used in the toner of the present invention will be described. As the inorganic fine particles that can be used as an external additive, conventionally known ones can be mentioned. Specifically, silica fine particles, titanium fine particles, alumina fine particles and the like can be preferably used. These inorganic fine particles are preferably hydrophobic.

Specific examples of the silica fine particles include commercially available products R-805, R-976 and R- manufactured by Nippon Aerosil Co., Ltd.
974, R-972, R-812, R-809, HVK-2150, H-200 manufactured by Hoechst Co., Ltd., and commercial products TS-720, TS-530, TS manufactured by Cabot Co., Ltd.
-610, H-5, MS-5, etc. are mentioned.

Specific examples of titanium fine particles include, for example,
Commercial products T-805 and T-60 manufactured by Nippon Aerosil Co., Ltd.
4. Commercial products MT-100S, MT-1 manufactured by Teika Co., Ltd.
00B, MT-500BS, MT-600, MT-60
0SS, JA-1, commercial product TA- manufactured by Fuji Titanium Co., Ltd.
300SI, TA-500, TAF-130, TAF-
510, TAF-510T, commercial products IT-S, IT-OA, IT-OB, IT-OC manufactured by Idemitsu Kosan Co., Ltd. and the like can be mentioned.

Specific examples of the alumina fine particles are, for example, commercially available products RFY-C and C- manufactured by Nippon Aerosil Co., Ltd.
604, a commercial product TTO-55 manufactured by Ishihara Sangyo Co., Ltd., and the like.

Examples of the organic fine particles usable as the external additive include spherical fine particles having a number average primary particle diameter of about 10 to 2000 nm. Examples of the constituent material of such organic fine particles include polystyrene, polymethylmethacrylate, and styrene-methylmethacrylate copolymer.

Examples of the lubricant that can be used as an external additive include metal salts of higher fatty acids. Specific examples of such metal salts of higher fatty acids include zinc stearate, aluminum stearate, copper stearate, magnesium stearate, calcium stearate, and other stearic acid metal salts; zinc oleate, manganese oleate, iron oleate, and olein. Oleic acid metal salts such as copper acid and magnesium oleate; Metal palmitate salts such as zinc palmitate, copper palmitate, magnesium palmitate and calcium palmitate; Metal linoleate salts such as zinc linoleate and calcium linoleate; Ricinol Examples thereof include metal salts of ricinoleic acid such as zinc acid salt and calcium ricinoleate.

The addition amount of the external additive is preferably about 0.1 to 5 mass% with respect to the toner.

The step of adding the external additive will be described. This step is a step of adding an external additive to the dried toner particles.

The equipment used for adding the external additive includes a Turbuler mixer, a Hensiel mixer,
Various known mixing devices such as a Nauta mixer and a V-type mixer can be mentioned.

The particle size of the electrostatic image developing toner of the present invention will be described. The number average particle diameter of the toner of the present invention is preferably 3 to 10 μm, and more preferably 3 to 8 μm. This particle size can be controlled by the concentration of the aggregating agent, the amount of the organic solvent added, the fusing time, and the composition of the polymer in the toner production method described in detail later.

When the number average particle diameter is 3 to 10 μm, the number of toner fine particles having a large adhesive force which fly and adhere to the heating member to generate an offset in the fixing step is reduced, and the transfer efficiency is increased. The image quality of halftone is improved, and the image quality of thin lines and dots is improved.

The number average particle diameter of the toner is, Coulter Counter TA-II, Coulter Multisizer, SLAD
1100 (a laser diffraction particle size measuring device manufactured by Shimadzu Corporation) can be used for the measurement.

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 100 μm aperture was used in the Coulter Multisizer, and the volume distribution of the toner of 2 μm or more (for example, 2 to 40 μm) was measured to calculate the particle size distribution and the average particle size.

The shape factor of the toner particles of the present invention will be described. 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 that when a projected image of a toner particle on a plane is sandwiched by two parallel lines, the parallel line 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 determined by taking a photograph of the toner particles magnified 2000 times with a scanning electron microscope, and then using this photograph, "SCANNING" is taken.
It was measured by analyzing a photographic image using "IMAGE ANALYZER" (manufactured by JEOL Ltd.). At this time, the shape factor of the present invention was measured by the above calculation formula using 100 toner particles.

In the above constitutions (1) and (9), it is preferable that the number of toner particles having the shape factor in the range of 1.0 to 1.6 is 65% by number or more, and more preferably 70% by number. % Or more. More preferably, the number of toner particles having the shape factor in the range of 1.2 to 1.6 is 65% by number or more, and more preferably 7
It is 0% by number or more.

When the number of toner particles having the shape factor in the range of 1.0 to 1.6 is 65% by number or more, the triboelectrification property in the developer carrying member becomes more uniform, and the excessively charged toner is obtained. Is not accumulated and the toner is more easily exchanged than on the surface of the developer transport member, so that problems such as development ghost are less likely to occur. Further, the toner particles are less likely to be crushed, the contamination of the charging member is reduced, and the charging property of the toner is stabilized.

Further, in the above-mentioned constitution (16), it is necessary that the number of toner particles having the shape factor in the range of 1.2 to 1.6 is 65% by number or more, preferably,
70% by number or more.

The method of controlling this shape coefficient is not particularly limited. For example, a method of spraying toner particles in a hot air stream, a method of repeatedly applying mechanical energy by impact force in a gas phase in a gas phase, or a method of adding a toner to a solvent that does not dissolve toner to give a swirling flow, etc. To prepare a toner having a shape factor of 1.0 to 1.6, or 1.2 to 1.6, and add the toner to an ordinary toner so that the toner falls within the range of the present invention. There is. Also, the overall shape is controlled at the stage of adjusting the so-called polymerization toner, and the shape factor is 1.0 to 1.6,
Alternatively, there is a method in which a toner adjusted to 1.2 to 1.6 is similarly added to a normal toner for adjustment.

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 horizontal axis, and the horizontal axis is on the basis of the number divided into a plurality of classes at intervals of 0.23. In the histogram showing the particle size distribution, the sum (M) of the relative frequency (m1) of toner particles contained in the most frequent class and the relative frequency (m2) of toner particles contained in the next most frequent class. ) Is preferably 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 step. 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 individual toner particles) in a plurality of classes (0 to 0) at intervals of 0.23.
0.23: 0.23 to 0.46: 0.46 to 0.69:
0.69 to 0.92: 0.92 to 1.15: 1.15
1.38: 1.38 to 1.61: 1.61 to 1.84:
1.84-2.07: 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 [ISOTON R-1
1 (manufactured by Coulter Scientific Japan)
An appropriate amount of a surfactant (neutral detergent) is added to 50 to 100 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 "cornerless toner particles" according to the present invention will be described with reference to FIG. In the toner according to the present invention, the proportion of toner particles having no corners in the toner particles constituting the toner is preferably 50% by number or more, more preferably 70% by number or more.

When the proportion of the toner particles having no corners is 50% by number or more, the voids of the transferred toner layer (powder layer) are reduced, the fixing property is improved, and the offset is less likely to occur. Further, the toner particles that are easily worn or broken and the toner particles having a portion where the electric charge is concentrated are reduced, the charge amount distribution becomes sharp, the chargeability becomes stable, and good image quality can be formed for a long time.

The term "cornerless toner particles" as used herein refers to toner particles having substantially no protrusions on which electric charges are concentrated or protrusions that are easily worn by stress.
Specifically, the following toner particles are referred to as cornerless toner particles. That is, as shown in FIG. 1A, the 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 rolled while making contact with the inside of the toner particle T at one point, the case where the circle C does not substantially extend outside the toner T is referred to as “toner particle without corners”. The term “when substantially not protruding” means a case where there is one or less protrusions with protruding circles. Also,
The “major axis of toner particles” refers to the width of the particles that maximizes the distance between the parallel lines when the projected image of the toner particles on a plane is sandwiched by two parallel lines. Note that FIGS. 1B and 1C show projected images of toner particles having corners, respectively.

The proportion of toner particles having no corners was measured as follows. First, a photograph of a magnified toner particle is taken with a scanning electron microscope and further magnified to 15,0.
A photographic image of 00 times is obtained. Then, the presence or absence of the above-mentioned corner is measured for this photographic image. This measurement was performed on 100 toner particles.

The method for obtaining 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.

The developer used in the present invention will be described. The toner of the present invention may be used as a one-component developer or a two-component developer.

When used as a one-component developer, the non-magnetic one-component developer or toner contains 0.1 to 0.5 μm.
A magnetic one-component developer containing a certain amount of magnetic particles can be used, and any one can be used.

Also, it can be used as a two-component developer by mixing with a carrier. In this case, as the carrier magnetic particles, metals such as iron, ferrite and magnetite,
Conventionally known materials such as alloys of these metals with metals such as aluminum and lead can be used. Ferrite particles are particularly preferable. The volume average particle diameter of the magnetic particles is 15 to 100 μm, and more preferably 25 to 8 μm.
0 μm is preferable.

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 one 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.

The image forming method of the present invention will be described.
The toner of the present invention comprises an image forming method including a step of passing an image forming support on which a toner image is formed between a heating roller and a pressure roller constituting a fixing device to fix the image forming support (image forming of the present invention. Method).

FIG. 2 is a cross-sectional view showing an example of a fixing device used in the image forming method of the present invention. The fixing device shown in FIG. 2 includes a heating roller 10 and a pressure roller 20 contacting the heating roller 10. I have it. In FIG. 2, T
Is a toner image formed on a transfer paper (image forming support).

The heating roller 10 has a coating layer 12 made of fluororesin or an elastic material formed on the surface of a cored bar 11, and contains a heating member 13 made of a linear heater.

The cored bar 11 is made of metal and has an inner diameter of 10 to 70 mm. The metal forming the cored bar 11 is not particularly limited, but examples thereof include metals such as iron, aluminum, and copper, and alloys thereof.

The core metal 11 has a wall thickness of 0.1 to 15 mm, and is determined in consideration of a balance between a request for energy saving (thinning) and strength (depending on constituent materials). For example,
In order for the core metal made of aluminum to maintain the same strength as the core metal made of iron of 0.57 mm, it is necessary to make the wall thickness 0.8 mm.

The fluororesin forming the coating layer 12 includes PTFE (polytetrafluoroethylene) and P.
FA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) etc. can be illustrated.

The thickness of the coating layer 12 made of fluororesin is 1
The thickness is 0 to 500 μm, and preferably 20 to 400 μm.

The coating layer 12 made of fluororesin has a thickness of 1
When the thickness is less than 0 μm, the function as the coating layer cannot be sufficiently exhibited, and the durability as the fixing device cannot be ensured. On the other hand, there is a problem in that the surface of the coating layer having a thickness of more than 500 μm is easily scratched by paper dust, and toner or the like adheres to the scratched portion, resulting in image stain.

As the elastic body forming the coating layer 12, it is preferable to use silicone rubber or silicone sponge rubber having good heat resistance such as LTV, RTV and HTV.

Asker C, which is an elastic material constituting the coating layer 12
The hardness is less than 80 °, preferably less than 60 °.

The thickness of the elastic coating layer 12 is 0.1 to 30 mm, preferably 0.1 to 20 mm.
It is said that

Asker C, which is an elastic material constituting the coating layer 12
If the hardness exceeds 80 ° and the thickness of the coating layer 12 is less than 0.1 mm, the fixing nip cannot be increased, and the effect of soft fixing (for example, the smoothed interface Effect of improving color reproducibility by toner layer)
Can't exert.

As the heating member 13, a halogen heater can be preferably used. The pressure roller 20 is
A coating layer 22 made of an elastic body is formed on the surface of the cored bar 21. The elastic body forming the coating layer 22 is not particularly limited, and various soft rubbers such as urethane rubber and silicone rubber and sponge rubber can be exemplified. The silicone rubbers exemplified as those forming the coating layer 12 and It is preferable to use silicone sponge rubber.

Asker C, which is an elastic material constituting the coating layer 22
The hardness is less than 80 °, preferably less than 70 °, and more preferably less than 60 °.

The coating layer 22 has a thickness of 0.1 to 30 m.
m, preferably 0.1 to 20 mm.

Asker C, which is an elastic material constituting the coating layer 22
If the hardness exceeds 80 ° and the thickness of the coating layer 22 is less than 0.1 mm, the fixing nip cannot be increased and the soft fixing effect cannot be exhibited.

The material for the cored bar 21 is not particularly limited, but examples thereof include metals such as aluminum, iron and copper, and alloys thereof.

The contact load (total load) between the heating roller 10 and the pressure roller 20 is usually 40 to 350 N, preferably 50 to 300 N, and more preferably 50.
~ 250N. This contact load is applied to the heating roller 1
The strength is defined as 0 (thickness of the core metal 11), and for a heating roller having a core metal of, for example, 0.3 mm of iron, it is preferably 250 N or less.

From the viewpoint of offset resistance and fixing property, the nip width is preferably 4 to 10 mm, and the surface pressure of the nip is 0.6 × 10 5 Pa to 1.5.
It is preferably × 105 Pa.

If one example of the fixing conditions by the fixing device shown in FIG. 2 is shown, the fixing temperature (surface temperature of the heating roller 10)
Is set to 150-210 ° C, and the fixing linear velocity is 80-640m.
m / sec.

The fixing device used in the present invention may be provided with a cleaning mechanism if necessary. In this case, as a method of supplying silicone oil to the upper roller (heating roller) of the fixing unit, a method of supplying and cleaning with a pad, roller, web, etc. impregnated with silicone oil can be used.

As the silicone oil, those having high heat resistance are used, and polydimethyl silicone, polyphenylmethyl silicone, polydiphenyl silicone and the like are used. Since those having a low viscosity have a large outflow amount at the time of use, those having a viscosity at 20 ° C. of 1 to 100 Pa · s are preferably used.

However, the effect of the present invention is particularly remarkable when the step of forming an image is performed by the fixing device which does not supply the silicone oil or the supply amount of the silicone oil is extremely low. Therefore, even if silicone oil is supplied, the amount supplied is 2 mg.
/ A4 or less is preferable.

The supply amount of silicone oil was 2 mg / A4.
Transfer paper after fixing (image support) by
The amount of silicone oil adhered to the transfer paper is reduced, there is no difficulty in writing with an oil-based pen such as a ballpoint pen due to the silicone oil adhered to the transfer paper, and the writing property is not impaired.

Further, it is possible to avoid problems such as deterioration of offset resistance over time due to alteration of the silicone oil and contamination of the optical system and the band electrode by the silicone oil.

Here, the amount of silicone oil supplied was measured by the transfer paper (A) to the fixing device (between rollers) heated to a predetermined temperature.
100 sheets of 4 sizes of white paper) are continuously passed, and the mass change (Δw) of the fixing device before and after passing the paper is measured and calculated (Δw / 100).

[0235]

The present invention is described in detail below with reference to examples, but the present invention is not limited to these.

Example 1 Latex 1HML and latex 2 were prepared as follows.
L (for shelling) and a colorant dispersion were prepared, and colored particles 1 were prepared using them.

<< Preparation of Latex >> (Preparation of Latex 1HML) (1) Preparation of Latex (1H) (First Stage Polymerization: Preparation of Core Particles) 5000 ml equipped with a stirrer, temperature sensor, cooling tube, nitrogen introducing device In a separable flask of No. 4, 4.0 g of the compound (5) of the general formula (1) and 300 deionized water
A surfactant solution (aqueous medium) dissolved in 0 g was charged, and the internal temperature was raised to 80 ° C. while stirring at a stirring speed of 230 rpm under a nitrogen stream.

To this surfactant solution, an initiator solution prepared by dissolving 10 g of a polymerization initiator (potassium persulfate: KPS) in 400 g of ion-exchanged water was added, and the temperature was adjusted to 75 ° C., then 560 g of styrene and n- Butyl acrylate 200
g, 40 g of methacrylic acid are added dropwise over 1 hour, and the system is heated at 75 ° C. for 2 hours with stirring to carry out polymerization (first-stage polymerization) to obtain a latex (high molecular weight). A dispersion liquid of resin particles consisting of resin was prepared. This is designated as "latex (1H)".

(2) Preparation of latex (1HM) (second-stage polymerization: formation of intermediate layer) In a flask equipped with a stirring device, styrene 9 was added.
5 g, n-butyl acrylate 36 g, methacrylic acid 9
A compound represented by the above formula 19) (hereinafter, referred to as “exemplary compound (19)”) as a crystalline substance was added to a monomer mixture liquid containing 0.59 g of g, n-octyl-3-mercaptopropionic acid ester. ) 77 g was added, and the mixture was heated to 90 ° C. and dissolved to prepare a monomer solution.

On the other hand, the compound (5) of the general formula (1) was treated with 1.
0 g, a surfactant solution dissolved in 1560 ml of deionized water was heated to 98 ° C., and 28 g of the latex (1H), which is a dispersion liquid of core particles, was added to the surfactant solution in terms of solid content, A monomer solution of the exemplified compound (19) was mixed and dispersed for 8 hours by a mechanical disperser having a circulation path "CLEARMIX" (manufactured by M Technique Co., Ltd.) to obtain a dispersed particle diameter (284n).
Dispersion (emulsion) containing emulsion particles (oil droplets) having m)
Was prepared.

Then, to this dispersion (emulsion) was added an initiator solution prepared by dissolving 5 g of a polymerization initiator (KPS) in 200 ml of deionized water, and the system was heated and stirred at 98 ° C. for 12 hours. Polymerization (second-stage polymerization)
Then, a latex (dispersion liquid of composite resin particles having a structure in which the surface of resin particles made of a high molecular weight resin is coated with an intermediate molecular weight resin) was obtained. This is "latex (1H
M) ”.

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 were obtained.
(0 to 1000 nm) was observed.

(3) Preparation of Latex 1HML (Third Stage Polymerization: Formation of Outer Layer) 6.8 g of a polymerization initiator (KPS) was dissolved in 265 ml of deionized water in the latex (1HM) obtained as described above. The added initiator solution was added, and styrene 249 g, n-butyl acrylate 88.
A monomer mixture liquid consisting of 2 g, 24.3 g of methacrylic acid and 7.45 g of n-octyl-3-mercaptopropionic acid ester was added dropwise over 1 hour. After completion of the 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 part made of a high molecular weight resin, an intermediate layer made of an intermediate molecular weight resin,
A composite resin particle dispersion having an outer layer made of a low molecular weight resin and containing the exemplary compound (19) in the intermediate layer was obtained. This latex is "Latex 1HML"
And

The composite resin particles constituting this latex 1HML are 138,000, 80,000 and 13,
The composite resin particles had a peak molecular weight of 000 and the weight average particle diameter of the composite resin particles was 122 nm.

(Preparation of latex 2L: for shelling)
In a 5000 ml separable flask equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introducing device, 4.0 g of the compound (5) of the general formula (1) and 300 g of ion-exchanged water were added.
A surfactant solution (aqueous medium) dissolved in 0 g was charged, and the internal temperature was raised to 80 ° C. while stirring at a stirring speed of 230 rpm under a nitrogen stream.

An initiator solution prepared by dissolving 10 g of a polymerization initiator (potassium persulfate: KPS) in 400 g of ion-exchanged water was added to this surfactant solution, and the temperature was adjusted to 75 ° C., then 560 g of styrene and n- Butyl acrylate 200
g, 40 g of methacrylic acid, and 25 g of n-octyl-3-mercaptopropionic acid ester were added dropwise over 1 hour, and the system was heated at 75 ° C. for 2 hours with stirring to perform polymerization. went. This is designated as "latex 2L".

<< Dispersion of Colorant >> 97 g of the compound (5) of the general formula (1) was dissolved with stirring in 1600 ml of ion-exchanged water. While stirring this solution, C.I. I. Pigment Red 122 and 420.0 g are gradually added, and then the stirring device "Clearmix" (M Technique Co., Ltd.)
A dispersion liquid of colorant particles (hereinafter referred to as “colorant dispersion liquid 1”) was prepared by performing a dispersion treatment using The particle size of the colorant particles in this colorant dispersion 1 was measured by using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.) and found to be 110 nm.

<< Preparation of Colored Particles 1 >> (Aggregation / fusion, association of latex 1HML composite resin particles and colorant particles) Latex 1HML 420.7 g (as solid content), ion-exchanged water 900 g and "colorant dispersion liquid" 1 ”and 200 g, a reaction container (four-necked flask) equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a stirring device.
And stirred. After adjusting the temperature in the container to 30 ℃,
The pH of the solution was adjusted to 8 to 11.0 by adding a 5 mol / liter sodium hydroxide aqueous solution.

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 being left for 3 minutes, and this system was heated to 90 ° C. over 60 minutes. In that state, the particle size of the associated particles was measured with a “Coulter counter TA-II”, and when the number average particle size reached 4 to 7 μm, sodium chloride 4
An aqueous solution in which 0.2 g was dissolved in 1000 ml of ion-exchanged water was added to stop grain growth, and further, as aging treatment, heating and stirring were performed at a liquid temperature of 98 ° C. for 6 hours to continue fusion bonding.

(Shelling operation) 96 g of latex 2L (dispersion liquid of resin particles) was further added after the aggregation / fusion and association treatments described above, and heating and stirring was continued for 3 hours to prepare latex (1HML). 2 L of latex was fused on the surface of the aggregated particles. Where sodium chloride 40.2
g was added, the mixture was cooled to 30 ° C. under the condition of 8 ° C./min, hydrochloric acid was added to adjust pH to 2.0, and stirring was stopped. The salted-out, aggregated, and fused particles produced are filtered, washed with 45 ° C. ion-exchanged water, which is 100 times the solid content of the colored particles, and then dried with hot air at 40 ° C. to give colored particles. Got 1.

<< Preparation of Colored Particle 2 >> In preparation of colored particle 1, latex (1H), latex (1HM),
Colored particles 2 were prepared in the same manner except that the compound (5) of the latex 2L was changed to the compound (6).

<< Preparation of Colored Particle 3 >> In the preparation of colored particle 1, latex (1H), latex (1HM),
Colored particles 3 were produced in the same manner except that the compound (5) of the latex 2L was changed to the compound (7).

<< Preparation of Colored Particle 4 >> In the preparation of colored particle 1, latex (1H), latex (1HM),
Colored particles 4 were produced in the same manner except that the compound (5) of latex 2L was changed to the compound (8).

<< Preparation of Colored Particles 5 >> Colored particles 5 were prepared in the same manner as in preparation of colored particles 1, except that the amount of compound (5) in colorant dispersion 1 was changed to 150 g.

<< Preparation of Colored Particle 6 >> In preparation of the colored particle 1, the amount of the compound (5) in the latex (1HM) was adjusted to 0.
Colored particles 6 were prepared in the same manner except that the amount of washing water was changed to 5 g, and 45 ° C. ion-exchanged water, which was 500 times the solid content of the colored particles, was used.

<< Preparation of Colored Particle 7 >> In the preparation of Colored Particle 1, magnesium chloride-6 in the aggregation / fusion step was used.
Colored particles 7 were prepared in the same manner except that the amount of hydrate was changed to 50 g.

<< Preparation of Colored Particle 8 >> In the preparation of Colored Particle 1, magnesium chloride-6 in the aggregation / fusion step is used.
Colored particles 8 were similarly prepared except that the amount of hydrate was changed to 5 g.
Was produced.

<< Preparation of Colored Particles 9 >> Magnesium chloride-6 in the aggregation / fusion step in the preparation of colored particles 1
Colored particles 9 were prepared in the same manner except that the amount of hydrate was changed to 35 g.

<< Preparation of Colored Particles 10 >> In the preparation of the colored particles 1, magnesium chloride
Colored particles 10 were produced in the same manner except that the amount of hexahydrate was changed to 25 g.

<< Preparation of Colored Particle 11 >>: Compound (5) used for preparing latex (1H), latex (1HM) and latex 2L in preparation of comparative colored particle 1 was changed to comparative compound 1, The colored particles 11 for comparison were prepared in the same manner except that the compound (5) of the colorant dispersion liquid 1 was changed to 150 g of the comparative compound 1 and the amount of magnesium chloride hexahydrate in the aggregation / fusion step was changed to 20 g. It was made.

Here, the comparative compound 1 has a compound having a straight-chain alkyl group having 12 carbon atoms which constitutes the main component of the compound (5), but the difference from the compound (5) is As described in No. 1, toners having different ratios of compounds having 6 to 22 carbon atoms are produced.

<< Preparation of Colored Particle 12 >>: The compound (5) used for preparing the latex (1H), the latex (1HM) and the latex 2L in the preparation of the comparative colored particle 1 was changed to the comparative compound 2, Comparative colored particles 12 were prepared in the same manner except that the compound (5) in the colorant dispersion liquid 1 was changed to 150 g of the comparative compound 2 and the amount of magnesium chloride hexahydrate in the aggregation / fusion step was changed to 20 g. did.

Here, the comparative compound 2 has a compound having a branched alkyl group having 12 carbon atoms which constitutes the main component of the compound (6), but the difference from the compound (6) is shown in Table 1. That is, toners having different ratios of compounds having 6 to 22 carbon atoms are produced.

<< Preparation of Colored Particles 13 >>: 5 g of the compound (5) used for preparing the latex (1HM) in preparation of the comparative colored particles 1 and the compound (5) used for preparation of the colorant dispersion 1 Comparative colored particles 13 were prepared in the same manner except that the amount used in was changed to 200 g.

<< Preparation of Electrostatic Image Developing Toners 1 to 10 and Comparative Toners 1 to 3 >> Colored Particles 1 to 1 prepared above
0, hydrophobic silica (number average primary particle diameter = 12 nm, degree of hydrophobicity = 68) was added to each of the colored particles 11 to 13 for comparison.
% By mass and hydrophobic titanium oxide (number average primary particle size = 20
nm, hydrophobicity = 63), and mixed with a Henschel mixer to obtain electrostatic image developing toners 1 to 10 and comparative toners 1 to 3, respectively.

There is no difference between the colored particles and the toner in terms of physical properties such as shape and particle size.

<< Preparation of Developer >> Electrostatic Image Developing Toner 1
No. 10 and Comparative Toners 1 to 3 were mixed with a silicone resin-coated ferrite carrier having a volume average particle diameter of 60 μm to prepare a developer so that the toner concentration would be 6%. These are developers 1 to 10 and comparative developer 1
~ 3.

Each of the obtained developers was photographed in the following manner, and the transparency of fog and OHP images was evaluated.

<Evaluation of Fog> A commercially available digital copying machine Konica Sitios 7075 was used as an evaluation machine, and 5000 images were continuously printed in a high-temperature and high-humidity environment (temperature 33 ° C., relative humidity 80%), and then the power was supplied. Was turned off and left for 72 hours for reprinting, the formed images were successively observed, the number of image stains (fogging) was counted, and rank evaluation was performed as follows.

⊚: 0 to less than 4 ○: 4 to less than 10 x: 10 or more In the present invention, the number of image stains (fogging) is 0 to.
If it was less than 10, it was judged as good (practical).

<Transparency of OHP Image> Regarding the transparency of the OHP image, a transparent image (OHP image) was prepared and evaluated by the following method. Note that the toner adhesion amount is 0.7 ±
The evaluation was made in the range of 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 Hitachi's "330 type self-recording spectrophotometer". With magenta toner, the spectral transmittance at 650 nm and 550 nm was measured. Was calculated and used as a measure of the transparency of the OHP image. When this value is 70% or more, it can be determined that the transparency is good.

[0272] ◎: 90% or more ◯: 70 to less than 90% X: less than 70% The results obtained are shown in Table 1.

[0273]

[Table 1]

From Table 1, the samples according to the invention compared with the comparison are:
It is clear that the fog is low and the transparency of the OHP image is good.

[0275]

According to the present invention, the fog is low, and
The toner for developing an electrostatic image having good OHP transparency, the method for producing the toner for developing an electrostatic image, and the image forming method can be provided.

[Brief description of drawings]

FIG. 1A is an explanatory diagram showing a projected image of toner particles without corners, and FIGS. 1B and 1C are explanatory diagrams showing projected images of toner particles with corners.

FIG. 2 is a sectional view showing an example of a fixing device used in the present invention.

[Explanation of symbols] 8 recording materials 10 heating roller 11 core 12 coating layer 13 Heating member 20 pressure rolls 21 core 22 coating layer T Toner image formed on recording material

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2H005 AA06 AB03 AB06 CA23 CB08                       DA10 EA07

Claims (5)

[Claims] 1. A toner for developing an electrostatic charge image produced through a step of fusing resin particles and colorant particles together in an aqueous medium, comprising at least two compounds represented by the following general formula (1): Included, and the content of the compound is 1 ppm to 1000
A toner for developing an electrostatic charge image, wherein the toner is ppm. [Chemical 1] [In the formula, R ₁ represents an aliphatic hydrocarbon group, but 50% by mass to 90% by mass in all compounds represented by the general formula (1)
The carbon number of R ₁ of the compound occupying is 6 to 22. R ₂ represents an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxyl group, an alkylthio group, an arylthio group, a heterocyclic oxy group or a heterocyclic group.
m represents an integer of 1 to 5 and n represents an integer of 0 to 4. M represents a monovalent metal element, a divalent metal element or an ammonium ion. ] 2. A polyvalent metal element of 250 ppm to 200
The toner for developing an electrostatic charge image according to claim 1, wherein the toner contains 100 ppm. 3. An electrostatic charge image developing toner according to claim 1 or 2, which comprises a step of polymerizing a polymerizable monomer in an aqueous medium to produce a resin. A method for producing a toner for developing a charge image. 4. The method for producing the toner for developing an electrostatic charge image according to claim 1, wherein the toner particles are produced through a step of aggregating and fusing resin particles in an aqueous medium. A method for producing a toner for developing an electrostatic charge image. 5. A step of forming an electrostatic charge image on an electrostatic charge image carrier, a step of developing the electrostatic charge image with a developer containing a toner for developing an electrostatic charge image to form a toner image, and a toner image. An image forming method including a step of transferring onto a transfer body, wherein the electrostatic image developing toner according to claim 1 is used as the electrostatic image developing toner.