JP2011164296A - Method for producing toner for electrostatic charge image development - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a toner, which suppresses sedimentation property or aggregation property of a colorant dispersion, shows a good dispersion state as a toner, and gives an image of high picture quality with appropriate image density and free of paper fog, afterimage and contamination. <P>SOLUTION: The method for producing a toner for electrostatic charge image development by using a colorant dispersion comprising a dispersion medium and a magenta colorant is characterized in that the volume median diameter Dv1 (μm) of the colorant and the viscosity η (cP) at 25°C in the colorant dispersion satisfy expression (1): η<41,360×(Dv1)<SP>2</SP>-12,800×Dv1+1,145 (wherein Dv1 is measured by a dynamic light scattering method and represents a particle diameter at a point where the volume particle size distribution cumulative curve of the colorant indicates 50%). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing a toner for developing an electrostatic image used for electrophotography, electrostatic photography and the like.

  In recent years, various organic pigments have been used mainly for applications such as paints, but they have also been used in a wide range of fields aiming at high functionality, such as resin colorants and ink jet printing inks. On the other hand, in order to maximize the ability of the pigment as a colorant, it is necessary to increase the surface area of the pigment. In many cases, organic pigments do not meet the target due to their strong cohesion. In particular, the dispersion of magenta organic pigments has a very high cohesive force acting between the molecules constituting the pigment, and its application range has been limited because it is difficult to disperse.

  Magenta pigments, for example, pigments typified by quinacridone and naphtholazo structures have high water resistance and light resistance, and can be dispersed in aqueous solvents in response to recent environmental problems as well as non-aqueous solvent dispersions. Although it is suitable for application and is considered to have a very wide range of application, it has been difficult to disperse and use because of its strong cohesive strength and hard pigment. In order to solve these problems, bead mills having extremely high dispersion efficiency with respect to input power have been used.

  Among the bead mills, the recent development of a bead separation device to efficiently separate the obtained dispersion from the beads has enabled the use of small particle size beads, which enables nano-sized dispersions to be made finer. Particleization is also possible. On the other hand, when the dispersion diameter is made finer, the pigment is often overdispersed. As a result, the particles agglomerate, causing problems such as sedimentation and thickening of the dispersion, and obtaining an optimal dispersion state according to the application. There are many problems such as difficult control.

  Pigment molecules are formed by a synthetic reaction and form primary particles, which are the smallest crystals, but these particles are strongly aggregated between crystal planes in units of several to several hundreds to form hard particles. It is common. These hard particles (aggregate) have a hierarchical structure in which they are further loosely bonded with a weak cohesive force due to point contact or the like. In general, in the pigment dispersion, it is necessary to quickly eliminate coarse powders formed from hierarchically aggregated aggregates, and at the same time, optimally adjust to a target particle size distribution. As described above, in order to increase the coloring power, it is necessary to reduce the size. However, as the surface area increases as the size reduction progresses, the light resistance decreases at the same time. When the broken particles are destroyed, active surfaces of new crystals come out, and the fine particles are newly bonded to each other and thicken (so-called overdispersed state). It was difficult to do.

  In the conventional method, for this control, the coarse powder processing and the particle size distribution optimization process are generally divided into two processes, which are complicated, and this is due to the complexity of the production line and process and the dispersion time. This is not preferable in terms of production efficiency. On the other hand, in order to speed up the dispersion, a method such as mild dispersion using a small-diameter bead in a bead mill to suppress the input power has been proposed in recent years. However, it also causes a longer dispersion time, which is not preferable in terms of production efficiency. In this case, if the input power is increased in order to increase the dispersion speed, an excessive dispersion state will be caused past the target particle size distribution, and the viscosity of the dispersion will be increased in the overdispersion state as described above. The problem occurred.

  For this reason, it is practically a problem in terms of production efficiency to improve the dispersion efficiency by using hard pigments such as magenta pigments with the target particle size distribution without problems such as re-aggregation and in a short time within one process. It was. In addition, it is preferable that the physical properties do not change after the dispersion in order to maintain the performance as an intermediate substance for the final product after being used in paints or inks after dispersion. Absent. In particular, when sedimentation occurs, problems such as uneven concentration of the dispersion and deterioration of color characteristics occur. On the other hand, a method for increasing the viscosity of the dispersion has been proposed in the past to prevent sedimentation, but when a thickener is added, the thickener has a considerable effect on the color characteristics and physical properties of the final product. give. In order to prevent this, when a system without a thickener is used, it is necessary to reduce the relative density difference between the pigment and the solvent to make it difficult to settle. In addition, it is also important to select the dispersant physical properties within an appropriate range.

  With respect to a magenta organic pigment dispersed as a colorant, the dispersion liquid can be used as an intermediate material for toners used in electrophotography. As an electrophotographic method using an organic pigment as a colorant, Patent Document 1 and Patent Document 2 describe various methods. In general, a photosensitive member using a photoconductive material is uniformly charged, an electric latent image is formed by means such as image exposure, and then the latent image is developed with toner to form a visible image, which is necessary. Accordingly, after transferring the toner image onto a transfer material such as paper, the toner image is fixed on the transfer material by heat, pressure or the like to obtain a copy or printed matter.

  In this process, the toner needs to maintain charging characteristics according to the purpose by frictional charging by contact with the member. This requires control from the chemical composition of the material as well as control of the physical contact process with the member. For example, a surface modification treatment in which a functional group is introduced by physicochemical treatment such as addition of a trace amount of inorganic, organic, or metallic substances to the toner headed by a substance such as a charge control agent, plasma treatment or introduction of a polar group, etc. The introduction of an additive is known as a known technique.

  Despite the fact that the production of toner by the polymerization method has been proposed for a long time, it was finally put into practical use in recent years, but it is also true that problems remain in terms of control such as toner charging stability. . Although the above-mentioned method has been considered as a countermeasure, on the other hand, since the polymerization method toner uses a large amount of surfactant / dispersion stabilizer in the production process, it cannot be completely removed. It is shown that one of the major causes is that charging control is difficult (Non-Patent Document 1). Further, the surfactant is not limited to the electrophotographic field, and the surfactant is widely used as an antistatic agent such as a resin. Therefore, it is clear that the surfactant deteriorates the charging characteristics of the toner. With respect to such problems, the above-described toner surface modification technology and the like cannot be expected to obtain an effect capable of controlling the charging characteristics of the toner according to the purpose, and the influence of the surfactant on the toner is not expected. No specific study was made.

  Known methods for producing polymerized toners include emulsion polymerization, suspension polymerization, dissolution suspension, ester extension, and dispersion polymerization. In particular, in the chargeability of toners produced by emulsion polymerization or dispersion polymerization, it is described that the chargeability changes depending on the humidity due to the influence of the dispersant and the emulsifier. It has been shown that the performance of the suspension polymerization toner cannot be exhibited (Non-patent Document 2). In this way, the use of surfactants and emulsifiers in the production process of polymerized toners (emulsion polymerization, dispersion polymerized toners, etc.) is indispensable. Therefore, finding a composition that optimally satisfies both manufacturability and toner characteristics has become a technical problem.

In order to minimize the influence of the remaining surfactant, the suspension polymerization method is used as a method for producing a polymerized toner using an inorganic suspension stabilizer and hardly using an organic surfactant in the first place. However, there are problems that the dispersibility of the color material and the release material inside the toner is poor and that the control of the toner shape is inferior to the emulsion polymerization method.
On the other hand, emulsion-polymerized toners are color materials that use cationic and anionic surfactants in the opposite nature to disperse the material, control the subsequent agglomeration process, and perform electrical coupling and neutralization. Methods of encapsulating a wax component as a pigment or a release agent and a surfactant inside a toner resin are disclosed (Patent Documents 1 and 2). Problems such as deterioration of charging property given to the toner by the activator have not been solved.

  In order to solve the above problem, there is a method of repeatedly washing after manufacturing the toner and washing and removing a substance such as a surfactant. However, a sufficient effect is not obtained due to variations in washing. Furthermore, there are many problems that are undesirable from a practical point of view, such as deterioration in manufacturability associated with an increase in the number of processes for repeated washing, an increase in the size of wastewater treatment facilities, and an increase in environmental burden.

  Compared to a two-component toner that is used in combination with a carrier, a one-component developer that does not use a carrier and uses only a toner has a triboelectric chargeability (charge rising speed, environmental stability, There is a problem in terms of long-term charging stability), and no one-component toner that satisfies these requirements has been proposed.

Japanese Patent Laid-Open No. 10-312084 JP 2005-215004 A

“Technology Trends of Toners and Constituent Materials” 2006 1st Edition, CM Publishing Co., Ltd. “Development of electrophotographic toner and constituent materials, high image quality, full color” 1998, 1st edition, Technical Information Association, Inc.

  As described above, there has been no method for achieving both toner manufacturability and toner performance using a colorant dispersion. Accordingly, the present invention provides a method for producing an electrostatic charge developing toner that solves the above problems.

The present inventor has found that the above problem can be solved by making the volume median diameter and viscosity of the colorant dispersion have a specific relationship with respect to a magenta colorant having particularly strong cohesive strength. That is, the present invention has the following characteristics.
1. A method for producing a toner using a colorant dispersion comprising a dispersion medium and a magenta colorant, wherein the colorant has a volume median diameter Dv1 (μm) and a viscosity η at a temperature of 25 ° C. (CP) satisfies the following formula (1): a method for producing an electrostatic charge image developing toner (Dv1 is measured by a dynamic light scattering method, and the volumetric particle size distribution cumulative curve of the colorant is 50%. Represents the particle size of the point.
^{η <41360 × (Dv1) 2} - 12800 × Dv1 + 1145 ···· (1)
2. 2. The method for producing a toner for developing an electrostatic charge image according to 1 above, wherein the dispersion medium contains at least a nonionic surfactant.
3. 3. The method for producing a toner for developing an electrostatic charge image according to 2 above, wherein the hydrophilic group portion of the nonionic surfactant is polyoxyethylene.
4). 4. The method for producing a toner for developing an electrostatic charge image according to 2 or 3 above, wherein the hydrophobic group portion of the nonionic surfactant is an alkyl ether.
5. 5. The method for producing a toner for developing an electrostatic charge image according to 2 to 4 above, wherein the nonionic surfactant has an HLB value of 10 or more and 17 or less.
6). 6. The method for producing a toner for developing an electrostatic charge image according to 2 to 5, wherein the nonionic surfactant has a cloud point of 90 ° C. or higher.
7). 7. The method for producing a toner for developing an electrostatic charge image according to 2 to 6, wherein the amount of the nonionic surfactant is 10 parts by mass or more with respect to 100 parts by mass of the magenta colorant.
8). 8. The electrostatic charge image developing toner according to any one of 1 to 7 above, wherein the volume median diameter Dv1 (μm) of the magenta colorant in the colorant dispersion satisfies 0.1 ≦ Dv1 ≦ 0.16. Production method.
9. The magenta colorant is C.I. I. 9. The method for producing a toner for developing an electrostatic charge image according to 1 to 8 above, which is Pigment Red 269.
10. A cylindrical stator, a colorant dispersion supply port and a colorant dispersion discharge port provided at one end of the stator, a medium filled in the stator, and a colorant dispersion supplied from the supply port are stirred and mixed. And a rotor that is connected to a discharge passage inlet that communicates with the discharge port and rotates integrally with the rotor, or rotates independently of the rotor. 10. The method for producing a toner for developing an electrostatic charge image according to the above 1 to 9, obtained by using a wet mill comprising a separator which is separated into a dispersion and discharges the colorant dispersion from an outlet.
11. 11. The method for producing a toner for developing an electrostatic charge image according to 10 above, wherein the diameter of the medium is from 0.1 mm to 1 mm.
12 12. The method for producing a toner for developing an electrostatic charge image according to 10 or 11 above, wherein the material of the medium is ZrO ₂ .

  According to the present invention, it is possible to suppress a settling property and agglomeration property of a colorant dispersion, a good dispersion state as a toner, and a high-quality image having an appropriate image density without paper fogging, afterimages, and stains. Obtainable.

It is a longitudinal cross-sectional view which shows an example of the wet mill (bead mill) used for this invention. It is the schematic which shows an example of the one-pass dispersion processing cycle of the coloring agent dispersion by the wet mill in connection with this invention. It is the schematic which shows an example of the circulation dispersion processing cycle of the coloring agent dispersion by the wet mill in connection with this invention.

1 Raw material tank
2 Raw material pump 3 Wet mill (bead mill)
4 rotating screen
5 Shaft
6 Jacket 7 Stator 8 Discharge path
9 Rotor 10 Raw material slurry supply port
11 Raw material slurry inlet
12 Valve
13 Valve 14 Valve 15 Valve
16 Product tank

  The present invention is a method for producing a toner using a colorant dispersion containing a dispersion medium and magenta colorant particles. Examples of the method for producing the toner using the colorant dispersion include wet methods such as a suspension polymerization method and an emulsion polymerization method, but are not particularly limited.

In the present invention, the volume median diameter Dv1 (μm) of the colorant of the colorant dispersion and the viscosity η (cP) at 25 ° C. are represented by the relationship of the following formula (1).
^{η <41360 × (Dv1) 2} - 12800 × Dv1 + 1145 ···· (1)
Formula (1) means that η is a quadratic function of D1 and is expressed by a downwardly convex curve, and represents the following. When the pigment is stably dispersed and does not cause so-called flocculation that causes weak aggregation after dispersion, the particles are individually present in the dispersion medium by the dispersant, and as a result, the total viscosity of the dispersion is the dispersion medium. This is explained by the volume filling effect in which fine particles are added to the original viscosity. On the other hand, when the dispersion progresses and the particle size is reduced, a new crystal face is exposed particularly in the organic pigment. Such a crystal face generally has poor adsorptivity of the dispersant, and as described above, it tends to lack the dispersion stability of the pigment and tends to cause flocculation between particles. Simple re-crushing (for example, stirring with anchor blades, short time stirring with a homogenizer, etc.), dispersion is easy to re-disperse, but the fluidity of the entire system is a viscosity without flocculation. In many cases, it does not reach as low as possible. That is, when the particle diameter is small, the viscosity of the entire dispersion rapidly increases due to the increased surface area of the particles and the network structure formed between the particles.

  On the other hand, when the volume filling rate is constant, the dispersed pigment generally has shape anisotropy in general, assuming that the particle diameter becomes larger. In the case of a small particle size, the primary dispersion diameter is a shape close to a sphere, but organic pigments typified by magenta have a crystal structure. The probability that a certain structure remains as it is is increased. When there is shape anisotropy, friction and bonding between the particles are likely to occur, and for this reason, an increase in the particle diameter causes a rise in the viscosity of the dispersion.

As described above, when the particle diameter of the dispersed particles is small and large, the viscosity of the entire dispersion system increases, and thus the viscosity value with respect to the particle diameter is a parabola that appears to be nearly convex, that is, mathematically Is expressed as a quadratic function as in equation (1).
Formula (1) shows the relationship between the volume median diameter and the viscosity of a colorant dispersion in which a magenta colorant with particularly strong cohesive force is in a good dispersion state as a toner and a high-quality image can be obtained. is there.

  In the colorant dispersion containing the colorant particles, if the formula (1) is not satisfied, the colorant particles are reaggregated to cause deterioration of the performance of the dispersion liquid. As a result, it is inevitable that the performance deteriorates greatly. In this case, even if agitation energy is applied, re-dispersion does not occur, or even if it is temporarily recovered, re-aggregation occurs immediately, and the problem of performance deterioration of the colorant dispersion becomes increasingly apparent.

  In the present invention, the volume median diameter Dv1 of the colorant in the toner colorant dispersion is preferably 0.1 μm or more, and particularly preferably 0.11 μm or more. Moreover, it is preferable that it is 0.16 micrometer or less, and it is especially preferable that it is 0.15 micrometer or less.

The ability of a pigment as a colorant depends on the molecular extinction coefficient of the molecules constituting the pigment and the surface area of the pigment particles. If the same pigment is compared, the molecular extinction coefficient is the same, so the coloring power depends only on the latter, and the surface area is inversely proportional to the particle diameter, so the smaller the particle, the higher the coloring power. If the mass% is the same, the smaller the particle diameter, the higher the coloring power. Therefore, it is possible to effectively color with a small amount. On the other hand, if the particles are too small, light resistance deteriorates when the particles are close to a dye, and dispersion stability also deteriorates, so that the viscosity of the dispersion may increase due to reaggregation. This is often not preferred when used as a colorant, and when applied to toner for developing electrostatic images, the coloring power to the toner resin is reduced, so the amount of pigment is increased accordingly. For this reason, the pigment exposed on the toner surface may cause deterioration of toner charging performance and printing characteristics.

  On the other hand, when the volume median diameter Dv1 is too large, in addition to the thickening caused for the reason described above, the stability as the colorant dispersion is poor, such as the particles dispersed during storage tend to settle, and coloring There is a tendency for power to decline.

In the present invention, the volume particle size distribution of the colorant particles in the colorant dispersion is measured by a dynamic light scattering method. This method obtains the particle size distribution by detecting the speed of Brownian motion of finely dispersed particles, irradiating the particles with laser light, and detecting light scattering (Doppler shift) with different phases according to the speed. It is. The value of the volume median diameter of these colorants is a value when the colorant is stably dispersed in the aqueous system, and does not mean the particle size of the colorant or wet cake as a powder before dispersion. . In actual measurement, the above volume particle size was measured using the following settings using an ultrafine particle size distribution measuring apparatus (Nikkiso Co., Ltd., UPA-EX150, hereinafter abbreviated as UPA) using a dynamic light scattering method. Do.
Measurement upper limit: 6.54 μm
Measurement lower limit: 0.0008 μm
Number of channels: 52
Measurement time: 100 sec.
Particle permeability: Absorption Particle refractive index: N / A (not applicable)
Particle shape: non-spherical density (g / cm ³ ): 1
Dispersion medium type: WATER
Dispersion medium refractive index: 1.333
At the time of measurement, the colorant dispersion is diluted with pure water so that the sample concentration index is in the range of 0.01 to 0.1, and the measurement is performed with a sample subjected to dispersion treatment with an ultrasonic cleaner.
Dv1 according to the present invention is measured by accumulating the above volume particle size distribution results from the small particle size side to obtain a volume cumulative distribution.

  The viscosity of the colorant dispersion is measured using an instrument or apparatus that is ordinarily widely used in accordance with JIS standards. For example, classic instruments such as capillary viscometers and falling ball viscometers, and commonly used rotary viscometers (coaxial double cylinder type, single cylinder type (B type viscosity depending on the shape of the rotating body) ), Cone plate type (E type viscometer)), but solutions often used in paints with pigments dispersed are often non-Newtonian fluids, so the use of a rotary viscometer is recommended. . Among these, although a relatively recent apparatus is slightly expensive, a frequency application type viscometer such as a viscoelasticity measuring apparatus (so-called rheometer) can be used as a highly versatile apparatus that can freely change the rotation speed. Moreover, although it is not recognized as a JIS standard, the vibration type viscometer which can measure more easily using a vibration type probe as a recent apparatus is also mentioned. The measuring jigs and probes used in these apparatuses have optimum shapes and sizes in their respective viscosity ranges, and it is necessary to select them appropriately in order to accurately measure the viscosity. The viscosity of the present invention is measured with an E-type viscometer described in Examples.

  The minimum value of the viscosity of the pigment dispersion is preferably 1 cP or more at 25 ° C. Moreover, it is preferable that it is 500 cP or less, More preferably, it is 100 cP or less, More preferably, it is 50 cP or less. If the viscosity is too high, the fluidity may deteriorate and the dispersion may become non-uniform, and the fluidity of the latex solution will deteriorate when used in toner production and will remain non-uniform when mixed. As a result, the toner characteristics may be deteriorated as they are. Although the non-uniformity is improved when the viscosity is 100 cP or more and 500 cP or less, the toner characteristics may be slightly bad. When the viscosity is 50 cP or more and 100 cP or less, the toner characteristics are also improved, but depending on the choice of the composition of the dispersant, it may be bad. If the composition is as follows, the toner characteristics can be significantly improved even with various compositions.

  The dispersion medium of the present invention is appropriately set from known materials according to the application purpose of the obtained colorant dispersion. Specifically, water; alcohols such as methanol, ethanol, propanol and butanol; organic solvents such as acetone, methyl ethyl ketone, tetrahydrofuran, toluene and xylene; monomers such as styrene, butyl acrylate, 2-ethylhexyl acrylate and acrylic acid These are used alone or in combination. As an application of the aqueous medium toner, for example, in the case of suspension polymerization toner, the colorant is dispersed in the oil phase, that is, the monomer phase. Therefore, the monomers may be selected as the wet medium. In this case, since the aggregation process is performed in an aqueous system, water may be selected as the dispersion medium. Among these, the particle size distribution of the colorant dispersion of the present invention is most suitable for use as a colorant dispersion added to polymer primary particles in an emulsion polymerization aggregation method toner. Is preferred. The water quality is also related to the coarsening due to re-aggregation of the colorant particles in the colorant dispersion, and if the electrical conductivity is high, the dispersion stability with time tends to deteriorate. Therefore, the electrical conductivity is preferably 10 μS / cm. In the following, it is preferable to use ion-exchanged water or distilled water that has been desalted so as to be 5 μS / cm or less. The conductivity is measured using a conductivity meter (personal SC meter model SC72 and detector SC72SN-11 manufactured by Yokogawa Electric Corporation).

The true density of the magenta colorant used in the present invention is 2.0 g / cm ³ when the true density of the pigment particles is measured by the pycnometer method specified in JIS K 5101-11-1: 2004.
Or less, more preferably 1.9 g / cm ³ or more, and 1.8 g / c.
Particularly preferred is m ³ or less. But preferably not more 1.2 g / cm ³ or more, and particularly preferably 1.3 g / cm ³ or more.
When the true density is too large, the sedimentation property in an aqueous medium tends to deteriorate. On the other hand, when the emulsion polymerization resin is used, for example, when the emulsion polymerization resin is too small, the density difference from the resin is large, and the distribution of the density is not uniform due to the density difference when the toner is aggregated.

  The magenta pigment of the present invention is preferably an organic magenta pigment in consideration of problems such as storage stability and sublimation. As the organic magenta pigment, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds are used. Specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 207, 209, 220, 221, 238, 254, 269, C.I. I. Pigment Violet 19 or the like is preferably used. Among them, C.I. I. A carmine pigment represented by CI Pigment Red 269 is particularly preferable. Although this carmine pigment was suitable as a magenta pigment because of its clear hue and high light resistance, the pigment itself is very hard particles, so it is difficult to control the dispersion, so its potential However, by using the production method of the present invention, excellent performance can be exhibited without reaggregation.

  The amount of the magenta colorant particles used in the colorant dispersion is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, and more preferably 10 parts by mass or more with respect to 100 parts by mass of water. Particularly preferred. Moreover, it is preferable that it is 50 mass parts or less, It is more preferable that it is 40 mass parts or less, It is especially preferable that it is 30 mass parts or less. When the amount of magenta colorant particles added satisfies the above range, it is preferable because reaggregation and excessive dispersion tend not to occur.

The colorant may have magnetism, and examples of the magnetic colorant include a ferromagnetic material that exhibits ferrimagnetism or ferromagnetism at a temperature around 0 to 60 ° C., which is a use environment temperature of a printer, a copying machine, and the like. For example, magnetite (Fe ₃ O ₄ ), maghemite (γ-Fe ₂ O ₃ ), intermediates and mixtures of magnetite and maghemite, MxFe ₃ -xO ₄ , where M is Mg, Mn, Fe, Co, Ni, Cu, Zn, spinel ferrite Cd, _{etc., BaO · 6Fe 2 O 3,} 6 -cubic ferrite such as _{SrO · 6Fe 2 O 3, Y} 3 Fe 5 O 12, Sm 3 Fe 5 O 12 , etc. garnet type oxide, rutile-type oxide such as CrO _2, and illustrates Cr, Mn, Fe, Co, the magnetic near 0 to 60 ° C. of such metal or their ferromagnetic alloys such as Ni The recited, among them, magnetite, maghemite, or intermediates magnetite and maghemite are preferred.

  When it is contained from the viewpoint of preventing scattering and charging control while having the characteristics as a non-magnetic toner, the content of the magnetic powder in the toner is preferably 0.2 parts by mass or more, and 0.5 parts by mass The above is more preferable, and 1 part by mass or more is particularly preferable. Moreover, 10 mass parts or less are preferable, 8 mass parts or less are more preferable, and 5 mass parts or less are especially preferable. When used as a magnetic toner, the content of the magnetic powder in the toner is preferably 15 parts by mass or more, and more preferably 20 parts by mass or more. Moreover, 70 mass parts or less are preferable, and 60 mass% or less is more preferable. If the content of the magnetic powder is too low, the magnetic force required for the magnetic toner may not be obtained, and if it is too high, poor fixability may occur.

Next, the developing principle of the toner will be described before selecting a preferred composition for the toner of the present invention, and then the reason for the selection will be sequentially described. In the electrostatic charge developing system, the toner is charged by transferring charges by friction. The surface functional group mainly affects the transfer of electric charge, and a representative factor is a functional group having an ionic dissociation group. The charge amount of the toner is governed by the dissociation constant and the number of functional groups, and an appropriate charging behavior is designed with an appropriate balance between the two. The former can be controlled by the type of functional group, and the latter can be controlled by the amount introduced. When the number of functional groups is the same, it is controlled by the number, but increasing the number is considered to be a good direction to increase the absolute value of the charge amount. On the other hand, if the number is excessive, the hygroscopicity of the toner due to ion dissociation also increases. . For this reason, for example, when considering the comparison of the charge amount between the case where the toner is placed in a high humidity environment and the case where the toner is placed in a normal humidity environment, the amount of change in charge with respect to the environment becomes large, and the former is extremely reduced. That is, the charging characteristics according to the environmental change of the toner and the image quality characteristics based on the charging characteristics are significantly affected, and the image quality is liable to deteriorate.
In the present invention, it is necessary to minimize the amount of the ionic functional group derived from the surfactant in the toner in order to optimally transfer and receive charges for the above reasons. This is because if the amount is more than the necessary amount, the balance of the charging behavior is lost, and the hygroscopicity of the toner due to ion dissociation increases, which is not preferable.

Specific examples of the anionic surfactant include fatty acid soaps such as potassium laurate, sodium oleate, and sodium castor oil as compounds containing a carboxylic acid group. Examples of the compound containing a sulfate group include octyl sulfate, lauryl sulfate, lauryl ether sulfate, and nonylphenyl ether sulfate. Compounds containing sulfonic acid groups include lauryl sulfonate, dodecyl sulfonate, dodecyl benzene sulfonate, triisopropyl naphthalene sulfonate, dibutyl naphthalene sulfonate and other alkyl naphthalene sulfonate sodium, naphthalene sulfonate formalin condensate; monooctyl sulfosuccinate, dioctyl sulfosuccinate And sulfonates such as lauric acid amide sulfonate and oleic acid amide sulfonate. Examples of the compound containing a phosphate group include phosphate esters such as lauryl phosphate, isopropyl phosphate, and nonylphenyl ether phosphate. Examples of the compound containing a succinic acid group include sodium dialkylsulfosuccinate such as sodium dioctylsulfosuccinate, disodium lauryl sulfosuccinate, and sulfosuccinates such as disodium lauryl polyoxyethylene sulfosuccinate. In particular, it is preferable to use a surfactant having a sulfonic acid group, but as a compound having a sulfonic acid group, an alkylbenzene sulfonate, a linear alkylbenzene sulfonate having an alkyl group having a linear structure, an α-olefin sulfonate, Examples include α-sulfo fatty acid ester salts. Among them, a compound having a sulfonic acid group and an alkyl group at the same time is preferable. In this case, the alkyl chain length should be 12 to 18 carbon atoms having a short carbon number and a low hydrophobicity and relatively easy to dissolve in water. Among them, it is preferable to use sodium dodecylbenzenesulfonate which is C12.

  Specific examples of the cationic surfactant include laurylamine hydrochloride, stearylamine hydrochloride, oleylamine acetate, stearylamine acetate, stearylaminopropylamine acetate, and other amine salts; lauryltrimethylammonium chloride, dilauryldimethylammonium Chloride, distearyl ammonium chloride, distearyl dimethyl ammonium chloride, lauryl dihydroxyethyl methyl ammonium chloride, oleyl bispolyoxyethylene methyl ammonium chloride, lauroylaminopropyldimethylethylammonium ethosulphate, lauroylaminopropyldimethylhydroxyethylammonium perchlorate, alkylbenzene dimethyl Ammonium chloride, alkyltri Quaternary ammonium salts such as chill chloride; and the like.

  Specific examples of nonionic surfactants include alkyl ethers such as polyoxyethylene octyl ether, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether; polyoxyethylene octylphenyl ether, polyoxyethylene Alkyl phenyl ethers such as nonylphenyl ether; alkyl esters such as polyoxyethylene laurate, polyoxyethylene stearate, polyoxyethylene oleate; polyoxyethylene lauryl amino ether, polyoxyethylene stearyl amino ether, polyoxyethylene oleyl Alkylamines such as amino ether, polyoxyethylene soybean amino ether, polyoxyethylene beef tallow amino ether; polyoxy Alkyl amides such as ethylene lauric acid amide, polyoxyethylene stearic acid amide, polyoxyethylene oleic acid amide; vegetable oil ethers such as polyoxyethylene castor oil ether and polyoxyethylene rapeseed oil ether; lauric acid diethanolamide, stearic acid Alkanolamides such as diethanolamide and oleic acid diethanolamide; sorbitan ester ethers such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate And so on. Of these, the use of polyoxyethylene alkyl ether is preferred.

  Specific examples of the amphoteric surfactant include alkylamine oxide, N-alkyl-β-alanine, alkylcarboxybetaine, dodecylamine oxide, dodecylsulfobetaine, dodecylbetaine; and the like.

As described above, the ionic functional group derived from the surfactant has an anionic property and a cationic property, and can be used for the production of toner. In particular, anionic surfactants having a sulfonic acid group are widely used in terms of performance such as high dispersibility, production cost, quality, stability, toxicity and the like. Although it can be used in all steps of the wet method such as emulsification, dispersion, polymerization, and aggregation, it is an indispensable material during emulsion polymerization. On the other hand, an ionic surfactant having a sulfonic acid group and an alkyl group at the same time has a highly hydrophobic structure. Therefore, when it is manufactured and washed in an aqueous system, it easily remains inside or on the surface of the toner. Since the ionic functional group lowers the charge of the toner and deteriorates the image, the amount that can be used is limited.

  Similar to the emulsion polymerization method, a toner production process mainly using an organic surfactant includes, for example, dispersion polymerization and ester extension polymerization. Dispersion polymerization is a method of polymerizing a polymer in a solvent that dissolves the monomer but hardly dissolves the produced polymer. A surfactant is dissolved mainly in a hydrophilic organic solvent such as alcohols, and a monomer and an initiator are further added for polymerization. As the polymerization proceeds, the polymer is insoluble or hardly soluble in the solvent, and thus precipitates to form particles, whereby a toner having a relatively sharp particle size distribution is obtained. In the ester extension polymerization method, materials such as resins, pigments, and waxes are dispersed in an organic solvent to prepare an oil phase. These are suspended and dispersed in water containing a surfactant to produce oil droplets in water. The oil droplets are converged to produce toner oil droplets having a sharp particle size distribution. In this process, the ester is simultaneously extended to synthesize a high molecular weight resin component. Finally, the solvent remaining in the toner oil droplets is removed to obtain a toner. In the present invention, by optimizing the surfactant in the step of dispersing the colorant, it is possible to obtain a dispersion of the colorant that achieves characteristics such as toner chargeability and high image quality.

  The physical properties of the surfactant must be optimized according to the type of colorant and medium, and when used as a colorant in the final toner manufacturing process, the most desirable physical properties must be maintained under the toner manufacturing conditions. I must. At the same time, it should not interfere with the charging characteristics of the toner, the toner printing properties, and the like. In order to stabilize the dispersion of the colorant, it is necessary to form an electric double layer or to have a steric repulsive force by charging the surfactant molecules adsorbed on the surface of the colorant. In order to form an electric double layer, the surfactant is preferably ionic. However, when ionic molecules are used, if this surfactant remains until the final step of toner production, the charging characteristics of the toner are adversely affected. From the above points, it is preferable that the selection of the surfactant includes at least nonionicity (nonionicity) that does not prevent the toner from being charged. In addition, in order to efficiently exhibit the steric repulsive force, a structure that makes it easy to design an optimum composition according to the surface properties of the colorant and the physical properties of the medium, that is, the hydrophilicity / hydrophobicity balance (HLB value) and temperature characteristics ( The use of a surfactant that can control the cloud point) is preferred.

  When the present invention is employed in the emulsion polymerization aggregation method, colorant particles can be uniformly contained in the toner, and a high image density can be provided. Further, in the obtained toner, the amount of fine powder generated can be reduced, and a good image can be provided.

  The hydrophilic group portion of the nonionic surfactant used for dispersing the colorant of the present invention is preferably polyoxyethylene. The hydrophobic group portion of the nonionic surfactant used for dispersing the colorant is preferably an alkyl ether. As described above, the amount of the anionic surfactant used is limited, and it is necessary to optimize the particle size distribution of the colorant in the colorant dispersion. In order to satisfy both of these, that is, to reduce the amount of the anionic surfactant brought into the toner from the colorant dispersion, it is preferable to use a nonionic surfactant for dispersion. By using these hydrophilic group part and hydrophobic group part, the molecular structure such as the hydrophilic / hydrophobic balance and the molecular weight is most easily designed, and the interaction among the three of the colorant, medium and surfactant is easily optimized.

In the present invention, in order to maintain the stability of the colorant particles after dispersion for a long time, one or more nonionic surfactants may be used, and at least nonionic properties may be used even when used in combination with other surfactants. It is preferable to include a surfactant. The amount of the surfactant used for dispersing the colorant of the present invention is usually preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more with respect to 100 parts by mass of water. Particularly preferred. Moreover, 15 mass parts or less are preferable, 10 mass parts or less are more preferable, and it is especially preferable that it is 5 mass parts or less. If the amount of the surfactant used is too large, it may be difficult to make the colorant finer, and the particle size distribution of the colorant of the present invention may not be obtained. There are cases where reaggregation of particles cannot be suppressed.

  The HLB value of the nonionic surfactant used for dispersing the colorant of the present invention is preferably 10 or more, more preferably 10.5 or more, and particularly preferably 11 or more. Also, it is preferably 17 or less, more preferably 16.5 or less, and particularly preferably 16 or less. When the HLB value is too small, the hydrophobicity is too high, so that there is a tendency that the surfactant cannot be uniformly dispersed in the aqueous medium, or the dispersion takes time and the production efficiency is lowered. On the other hand, if the HLB value is too large, the hydrophilicity is high, the affinity with the colorant cannot be maintained, and the dispersion stability is lowered. Therefore, aggregation between pigments occurs in the subsequent toner production process, and the amount of fine powder of the toner There is a tendency that the charging performance is deteriorated due to the increase of the toner and the cueing of the colorant to the toner surface.

  The HLB value (Hydrophilic-Hydrophobic Balance) representing the hydrophilicity / hydrophobicity balance of the present invention can be determined from the respective chain length ratios of the hydrophilic group portion and the hydrophobic group portion of the nonionic surfactant.

  The hydrophilicity / hydrophobicity of the nonionic surfactant molecule as a whole of the present invention also affects the cloud point of the nonionic surfactant. What is cloud point? When the temperature of a nonionic surfactant solution dissolved in water is raised, the entire system suddenly becomes cloudy and loses its surface activity, and the surfactant becomes finely oily and precipitates. Temperature. The HLB value is represented by the ratio between the molecular weight of the hydrophilic group and the overall molecular weight. When the HLB is small, that is, when the balance of the hydrophobic groups is large, the solubility in water and the cloud point decrease. It is used for producing a defoaming action and a W / O type emulsion as a property of the surfactant. On the other hand, when HLB is large, that is, when the balance of hydrophilic groups is large, the solubility in water and the cloud point increase. It is used to produce a solubilizing action, a washing action, and an O / W type emulsion as the properties of the surfactant.

  The cloud point of the nonionic surfactant of the present invention is preferably 90 ° C. or higher, more preferably 94 ° C. or higher, and particularly preferably 98 ° C. or higher. Moreover, it is preferable that it is 120 degrees C or less, It is more preferable that it is 115 degrees C or less, It is especially preferable that it is 110 degrees C or less. When the cloud point is too high, the dispersibility of the surfactant is abruptly reduced, and aggregation between the colorants tends to occur, and the storage stability tends to deteriorate. Further, in the toner manufacturing process, aggregation between the colorants tends to occur, and there is a tendency to increase the amount of fine powder of the toner and to deteriorate the charging performance accompanying the cueing of the colorant to the toner surface. Further, when the toner is washed with warm water or the like, the solubility with respect to the temperature is lowered, and thus there may be a problem that the washing property is deteriorated. On the other hand, when the cloud point is too low, the hydrophilicity of the surfactant may be too high. If the hydrophilicity is high, the dispersion of the pigment becomes too stable, making it difficult for the pigment to agglomerate in the toner manufacturing process, increasing the amount of fine powder due to the pigment not being incorporated into the toner, and charging due to adhesion of the colorant to the toner surface. There is a tendency to degrade performance.

The surfactant used for dispersing the colorant of the present invention is mainly a nonionic surfactant. However, the surfactant is not limited to the nonionic surfactant, and the same nonionic surfactant can be used. The type is not limited. In order to maintain the dispersion stability of the colorant itself, or in the case of using emulsion polymerization, it is possible to adjust using a plurality of surfactants in order to control the cohesiveness with the emulsion polymerized latex. In addition, an anionic surfactant may be used within a range in which the residual amount in the toner is allowed. At this time, the repulsion effect by the electric double layer may be used as a dispersion stabilization mechanism.

  In the present invention, the amount of the anionic surfactant used for dispersing the colorant is preferably 0.5 parts by mass or less and more preferably 0.2 parts by mass or less with respect to 100 parts by mass of the colorant. The amount is preferably 0.1 parts by mass or less. When the amount of the anionic surfactant is too large, the amount of the anionic surfactant remaining inside or on the surface of the toner increases, and the charging characteristics and image characteristics of the toner tend to deteriorate.

  The colorant dispersion liquid of the present invention is preferably adjusted using a wet mill (bead mill). The cylindrical stator, the colorant dispersion supply port provided at one end of the stator, and the colorant dispersion discharge are provided. A rotor that stirs and mixes the outlet, the medium filled in the stator and the colorant dispersion supplied from the supply port, and a discharge path inlet that communicates with the discharge port and rotates integrally with the rotor; Alternatively, a wet mill that rotates independently from the rotor, is separated into media and a colorant dispersion by the action of centrifugal force and a screen structure, and a separator that discharges the colorant dispersion from the discharge port is used. Is preferred. It is more preferable that the wet mill has a hollow discharge path that communicates with the discharge port around the axis of a shaft that rotationally drives the separator.

  The above-mentioned wet mill is a so-called bead mill, which is composed of a cylindrical sealed stator and a pin, a disk or an annular rotor that is disposed on the axis of the stator and is driven to rotate by a motor. In this state, a colorant dispersion comprising a dispersion medium and magenta colorant particles is supplied, and the rotor is driven to rotate, and the media and the magenta colorant dispersion are stirred and mixed to pulverize the colorant dispersion. It is.

  An example of a method for producing a colored dispersion containing the colorant particles will be described with reference to FIGS. FIG. 1 is a longitudinal sectional view showing an example of a wet mill (bead mill). The wet mill in FIG. 1 has a vertical or horizontal cylindrical shape. Here, the horizontal type will be described. The cylindrical portion includes a stator 7 provided with a jacket 6 through which cooling water for cooling the mill is passed, and a bearing that is positioned at the shaft center of the stator 7 so as to be rotatable at a mounting portion (base portion) of the stator. And a shaft 5 provided with a mechanical seal in the bearing portion and having a hollow discharge passage 8 around the axis of the root portion, and a pin or disk projecting radially from the shaft root to the end portion Rotor 9, a separator 4 fixed by a rotary centrifugal screen for media separation, and a colorant dispersion premix product supply port 10 provided on the side of the shaft 5 at the base of the stator. It consists of an inlet 11. The separator 4 rotates the shaft 5 together with the medium and applies a centrifugal force to the medium and the dispersion. The separator 4 disperses the medium radially outward due to the difference in specific gravity. It is made to discharge through the discharge path 8.

  This separator 4 applies centrifugal force to the media and the dispersion, and repels the heavy media by the difference in specific gravity between the media and the slurry, and further separates the media completely by filtering through a screen. The dispersion is discharged from the discharge passage around the shaft. Since it is a screen system, beads are not ejected from the stator, and micro media can be used. Since the flow rate and throughput can be increased and there is no change in separation performance over time, it can be operated stably over a long period of time, and since fine media can be used, it has the advantage that fine grinding is possible. Yes.

FIG. 2 is a schematic diagram showing an example of a one-pass treatment cycle of a colorant dispersion by a wet mill. In FIG. 2, the colorant dispersion slurry extracted by the raw material pump 2 from the raw material tank 1 for storing the premixed product such as the dispersion medium and the magenta colorant particles is supplied to the horizontal wet mill 3. After being pulverized by being stirred together with the medium, the medium is separated by the separator, discharged through the shaft axis, and collected in the product tank 30. A one-pass treatment cycle is suitable for crushing / dispersing loosely aggregated agglomerates.

  FIG. 3 is a schematic view showing an example of a circulation dispersion treatment cycle of a colorant dispersion by a wet mill according to the present invention. In FIG. 3, a magenta colorant dispersion slurry extracted by a raw material pump 2 from a raw material tank 1 for storing a premixed product such as a dispersion medium and magenta colorant particles is supplied to a horizontal wet mill 3. After being pulverized by being stirred together with the medium in 3, the medium is separated by the separator 4, discharged around the axis of the shaft 5, followed by a path returned to the tank 1, and circulated and crushed. Yes. The circulation dispersion treatment is used for crushing aggregate particles (aggregate) having a strong bond and homogenizing the particle size distribution.

  Next, a method for producing a colorant dispersion containing colorant particles will be described in more detail. The medium in the stator 7 of the mill 3 is filled with 80 to 90% of the internal volume of the stator, the valves 12 and 13 are closed, and the valves 14 and 15 are opened. 2 is driven. The rotor 9 and the separator 4 are driven to rotate by the former motor, while the colored dispersion premix slurry containing the colorant particles in the raw material tank 1 is supplied to the supply port 10 by a certain amount by the latter raw material pump 2. It is sent to the inlet 11 and supplied into the mill. The dispersion slurry and media in the mill are agitated and mixed by the rotation of the rotor 9 to pulverize the colorant particles, and the rotation of the separator 4 separates the media and the dispersion due to the difference in specific gravity. In contrast to being blown outward in the radial direction, the dispersion having a low specific gravity is filtered through a screen and then completely separated from the medium and discharged through a discharge path 8 formed around the axis of the shaft 5. The ratio of the feed rate of the raw material slurry to the mill and the effective internal volume of the stator is preferably in the range described below.

  Here, the raw material pump 2 is preferably a non-pulsating pump. In ordinary metering pumps, the rotational motion of the circular eccentric cam is changed to reciprocating motion, so pulsation occurs on the discharge side, and an accurate flow rate cannot be obtained. In some cases, a share is added, and inconvenience of accelerating reaggregation of the colorant particles in the colorant dispersion is likely to occur. The non-pulsating metering pump employs a constant velocity cam mechanism, etc., so that an accurate flow rate can be ensured even with a small amount and damage to the dispersion is difficult, so that reaggregation of the colorant particles can be avoided. Specific examples of the non-pulsating metering pump include a non-pulsating metering pump type PLSXMA2 (hydraulic diaphragm type), PLSXDA2 (direct acting diaphragm type) manufactured by Takumina Corporation.

  In the present invention, the selection of media beads is important. In particular, in order to obtain a preferable particle size distribution of the pigment particles, the diameter of the media is preferably 1 mm or less, more preferably 0.5 mm or less, and most preferably 0.2 or less. The lower limit is preferably 0.1 mm or more. In the case of beads exceeding the above range, since the destructive force due to collision is generally high, the time tends to increase the ultrafine particle portion of the colorant particles. Further, the dispersion time is long and the production efficiency is deteriorated. On the other hand, if the particle size is small, the ultrafine particle portion is formed immediately, and at the same time, the destructive force is weak even after a lapse of time. At the same time, these ultrafine particle portions actually reagglomerate and coarsen immediately, so that after all, a preferable particle size distribution may not be achieved. In addition, as the pulverization of the pigment particles proceeds, the pulverization efficiency of the beads having a large particle size decreases, and the contact point (action point) of the media beads decreases, so that a preferable particle size distribution may not be achieved. The media beads are monodisperse spherical particles, and variations in their diameters can be almost ignored.

A known material can be used for the media beads. For example, the following can be mentioned.
Zirconia (ZrO ₂ ), true density 6.0 g / cm ³
Silica, true density 2.6 g / cm ³
・ Glass, true density 2.5g / cm ³
・ Titanium oxide, true density 4.3 g / cm ³
Copper sphere, true density 8.9g / cm ³
Silicic acid zirconia (ZrSiO ₄ ), true density 3.8 g / cm ³
Among these, in order to smoothly separate the media and the colorant particles, it is preferable that the two have a certain density difference. Therefore, the true density of the media is preferably 5 or more. More preferably, the difference in density between the media and the colorant particles (less than 2.0 g / cm ³ ) is 3 or more. Among the media described above, zirconia (ZrO ₂ ) is preferable from the viewpoint of preventing contamination because it has high wear resistance and impact resistance and is difficult to crush in the manufacturing process. Further, the filling rate of the media is greatly related to the crushing ability, and is preferably 65 to 95% with respect to the stator effective internal volume (the crushing chamber volume excluding the volume occupied by the separator and the rotor from the total internal volume of the stator). More preferably, it is -90%.

  The colorant dispersion premix is obtained by predispersing water, a surfactant, and a pigment in advance with a stirrer, a homomixer, a homogenizer or the like equipped with a propeller blade, an anchor blade, etc. It is done. The particle diameter of the colorant in the premix product is preferably measured by the Coulter method, laser diffraction method, or the like, and the volume cumulative distribution is 50% in diameter and is 100 μm or less because a suitable particle size distribution can be easily obtained later.

  In the present invention, as the binder resin contained in the toner, resins conventionally used as the binder resin for toner can be used. For example, as a monomer, a polymerizable monomer having an acidic group (hereinafter sometimes simply referred to as an acidic monomer), a polymerizable monomer having a basic group (hereinafter simply referred to as a basic monomer) A polymerizable monomer having no acidic group or basic group (hereinafter, also referred to as other monomer) may be used. it can. In the case of the emulsion polymerization aggregation method, in the emulsion polymerization step, the polymerizable monomer is usually polymerized in an aqueous medium in the presence of an emulsifier. At this time, in supplying the polymerizable monomer to the reaction system, The monomers may be added separately or a plurality of types of monomers may be mixed in advance and added simultaneously. The monomer may be added as it is, or may be added as an emulsion mixed and adjusted in advance with water or an emulsifier.

  As the acidic monomer, a polymerizable monomer having a carboxyl group such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, cinnamic acid, a polymerizable monomer having a sulfonic acid group such as sulfonated styrene, Examples thereof include polymerizable monomers having a sulfonamide group such as vinylbenzenesulfonamide. Examples of the basic monomer include aromatic vinyl compounds having an amino group such as aminostyrene, nitrogen-containing heterocyclic-containing polymerizable monomers such as vinylpyridine and vinylpyrrolidone, dimethylaminoethyl acrylate, diethylaminoethyl methacrylate, etc. And (meth) acrylic acid ester having an amino group. These acidic monomers and basic monomers may be used singly or as a mixture of a plurality of types, and may exist as a salt with a counter ion. Among these, it is preferable to use an acidic monomer, more preferably acrylic acid and / or methacrylic acid.

  The total amount of the acidic monomer and the basic monomer in 100 parts by mass of the total polymerizable monomers constituting the binder resin is preferably 0.05 parts by mass or more, more preferably 0.5 parts by mass. As mentioned above, More preferably, it is 1 mass part or more, Preferably it is 10 mass parts or less, More preferably, it is 5 mass parts or less.

Examples of other polymerizable monomers include styrenes such as styrene, methylstyrene, chlorostyrene, dichlorostyrene, p-tert-butylstyrene, pn-butylstyrene, and pn-nonylstyrene, methyl acrylate, Acrylic esters such as ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, hydroxyethyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n methacrylate -Methacrylic acid esters such as butyl, isobutyl methacrylate, hydroxyethyl methacrylate, 2-ethylhexyl methacrylate, acrylamide, N-propylacrylamide, N, N-dimethylacrylamide, N, N-dipropylacrylic De, N, N-dibutyl acrylamide, and the like, the polymerizable monomer may be used singly, or may be used in combination.

  Furthermore, when the binder resin is a cross-linked resin, a polyfunctional monomer having radical polymerizability is used together with the above polymerizable monomer, for example, divinylbenzene, hexanediol diacrylate, ethylene glycol dimethacrylate, Examples include diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, neopentyl glycol diacrylate, and diallyl phthalate. It is also possible to use a polymerizable monomer having a reactive group in a pendant group, such as glycidyl methacrylate, methylol acrylamide, acrolein and the like. Among these, radically polymerizable bifunctional polymerizable monomers are preferable, and divinylbenzene and hexanediol diacrylate are particularly preferable. These polyfunctional polymerizable monomers may be used alone or as a mixture of plural kinds.

  As a polymerization initiator, a well-known polymerization initiator can be used 1 type or in combination of 2 or more types. For example, persulfates such as potassium persulfate, sodium persulfate, ammonium persulfate, and the like, and redox initiators combining these persulfates as a component with a reducing agent such as acidic sodium sulfite, hydrogen peroxide, 4,4 Water-soluble polymerization initiators such as' -azobiscyanovaleric acid, t-butyl hydroperoxide, cumene hydropeoxide, etc., and these water-soluble polymerization initiators as a component combined with a reducing agent such as ferrous salt Redox initiator systems, benzoyl peroxide, 2,2′-azobis-isobutyronitrile, and the like are used. These polymerization initiators may be added to the polymerization system before, simultaneously with the addition of the monomer, or after the addition, and these addition methods may be combined as necessary.

  In the present invention, a known chain transfer agent can be used as necessary. Specific examples of such a chain transfer agent include t-dodecyl mercaptan, 2-mercaptoethanol, diisopropylxanthogen, tetrachloride. Carbon, trichlorobromomethane, and the like. The chain transfer agent may be used alone or in combination of two or more, and is used in an amount of 0 to 5 parts by mass with respect to the polymerizable monomer.

  In addition, one or more types of suspension stabilizers such as calcium phosphate, magnesium phosphate calcium hydroxide, and magnesium hydroxide are added in an amount of 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer. May be used. Both the polymerization initiator and the suspension stabilizer may be added to the polymerization system at any time before, simultaneously with, or after the addition of the polymerizable monomer. You may combine. In addition, a pH adjuster, a polymerization degree adjuster, an antifoaming agent, and the like can be appropriately added to the reaction system.

In the production of toners such as an emulsion polymerization aggregation method, an ester extension polymerization method, and a dispersion polymerization, elemental technologies such as emulsification, dispersion, and polymerization are used. In each step, an emulsifier, a dispersant, and a surfactant are used, and an ionic surfactant is used as a main component thereof. To produce a fine dispersion of wax, which is a toner release agent, heat to a temperature higher than the melting point and treat it with a surfactant under high pressure in water and high shear force. For this reason, the surface active ability is lost at a high temperature, and it becomes difficult to obtain an emulsion that is stable in fine dispersion. For the same reason, for example, in emulsion polymerization, heating to near the boiling point with an aqueous solvent, it is difficult to obtain a stable polymer with a nonionic surfactant. That is, it is common to use an ionic surfactant having no cloud point in both steps. On the other hand, the remaining of the ionic surfactant causes deterioration of charged physical properties and image quality of the toner. Pigment dispersion is a process of dispersing a solid in a solution, and thus does not require heating as in emulsification or polymerization. That is, a nonionic surfactant can be used, and the problem of residual ionic surfactant and deterioration of toner performance can be solved. A method that can reduce the amount of the ionic surfactant that is brought in from each member and remains in the toner is to use a nonionic surfactant as a main component at the time of pigment dispersion.

  In the present invention, when the binder resin is polymerized by emulsion polymerization, known emulsifiers can be used, but one kind selected from a cationic surfactant, an anionic surfactant and a nonionic surfactant Alternatively, two or more emulsifiers can be used in combination. The use amount of the emulsifier is preferably 0.1 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer, and these emulsifiers include, for example, partially or completely polyvinyl alcohol such as saponified polyvinyl alcohol. One kind or two or more kinds of alcohols and cellulose derivatives such as hydroxyethyl cellulose can be used in combination as protective colloids. The volume average particle diameter of the polymer primary particles obtained by emulsion polymerization is usually 0.02 μm or more, preferably 0.05 μm or more, more preferably 0.1 μm or more, and usually 3 μm or less, preferably 2 μm or less, more preferably. Is desirably 1 μm or less. When the particle size is smaller than the above range, it may be difficult to control the aggregation rate in the aggregation process. When the particle size is larger than the above range, the particle size of the toner particles obtained by aggregation tends to be large, It may be difficult to obtain a toner having a particle size of

  In the present invention, when a charge control agent is used, any known one can be used alone or in combination. For example, a quaternary ammonium salt, a basic / electron-donating agent can be used as a positive charge control agent. Examples of negative charge control agents include metal chelates, metal salts of organic acids, metal-containing dyes, nigrosine dyes, amide group-containing compounds, phenol compounds, naphthol compounds and their metal salts, urethane bond-containing compounds , Acidic or electron withdrawing organic substances.

  When the toner for developing an electrostatic charge image of the present invention is used as a toner other than a black toner in a color toner or a full color toner, it is preferable to use a charge control agent that is colorless or light in color and does not impair the color tone of the toner. Quaternary ammonium salt compounds are used as positively chargeable charge control agents, and metal salts of salicylic acid or alkylsalicylic acid with chromium, zinc, aluminum, metal complexes, metal salts of benzylic acid, metals as negatively chargeable charge control agents. Preference is given to hydroxynaphthalene compounds such as complexes, amide compounds, phenolic compounds, naphthol compounds, phenolamide compounds, 4,4′-methylenebis [2- [N- (4-chlorophenyl) amide] -3-hydroxynaphthalene].

  When a charge control agent is included in the toner in the emulsion polymerization aggregation method, whether the charge control agent is added together with a polymerizable monomer or the like at the time of emulsion polymerization, or is added in the aggregation step together with the polymer primary particles and the colorant The polymer primary particles, the colorant and the like can be blended by a method of adding them after agglomeration to almost the desired particle size. Of these, it is preferable to disperse the charge control agent in water using a surfactant and add it to the aggregation step as a dispersion having a volume average particle size of 0.01 to 3 μm.

  Tg by the DSC (Differential Scanning Calorimetry) method of the binder resin constituting the polymer primary particles is preferably 40 to 80 ° C. Here, when the Tg of the binder resin overlaps with the heat amount change based on other components, for example, the melting peak of the wax and cannot be clearly determined, when the toner is prepared in a state in which such other components are excluded. Of Tg.

  The acid value of the binder resin constituting the polymer primary particles is preferably 3 to 50 mgKOH / g, more preferably 5 to 30 mgKOH / g as a value measured by the method of JISK-0070.

  As a blending method of the colorant in the emulsion polymerization aggregation method, the polymer primary particle dispersion and the colorant dispersion containing the colorant particles are usually mixed to form a mixed dispersion, and then this is agglomerated to aggregate the particles. Collect. The addition of the colorant dispersion at the time of emulsion aggregation is preferably used in an amount of 2 to 10% by mass in the finished mother particles after aggregation.

  In the present invention, it is preferable to add wax for imparting releasability. Any wax can be used as long as it has releasability, and is not particularly limited. Specifically, olefin waxes such as low molecular weight polyethylene, low molecular weight polypropylene, and copolymer polyethylene; paraffin wax; ester waxes having a long-chain aliphatic group such as behenyl behenate, montanate ester, stearyl stearate; water Plant waxes such as added castor oil carnauba wax; ketones having long chain alkyl groups such as distearyl ketone; silicones having alkyl groups; higher fatty acids such as stearic acid; long chain aliphatic alcohols such as eicosanol; glycerin, pentaerythritol, etc. Examples include carboxylic acid esters or partial esters of polyhydric alcohols obtained from polyhydric alcohols and long chain fatty acids; higher fatty acid amides such as oleic acid amide and stearic acid amide; low molecular weight polyesters and the like.

In the present invention, it is preferable to use a low melting point wax in order to improve fixability. Specifically, the melting point of the wax measured by DSC is preferably 30 ° C. or higher, more preferably 40 ° C. or higher, and particularly preferably 50 ° C. or higher. Moreover, 100 degrees C or less is preferable, 90 degrees C or less is still more preferable, and 80 degrees C or less is especially preferable. If the melting point is too low, the wax tends to be exposed and sticky after fixing, and if the melting point is too high, the fixability at low temperatures tends to be poor.
The wax compound species is preferably an ester-based wax that has an ester bond, is a solid at room temperature and becomes a low-viscosity fluid upon heating, and preferably has 20 to 100 carbon atoms. This is because if the number of carbon atoms is too small, the molecular weight is small, so that it is easy to diffuse and move, and it precipitates on the surface of the toner during heating during toner production, and tends to deteriorate the blocking resistance and charging performance of the toner. On the other hand, if the molecular weight is too large, the molecular weight is large, which is disadvantageous for diffusion movement. Therefore, it is difficult to move to the surface of the resin layer at the time of toner heat fixing, and the fixing temperature tends to increase. Examples include monoester compounds using higher fatty acids and higher monohydric alcohols as raw materials, and polyfunctional ester compounds using higher fatty acids and polyhydric alcohols as raw materials. Among them, polyfunctional ester compounds are preferred. Pentaerythritol tetrastearate, pentaerythritol tribehenate, dipentaerythritol hexastearate, dipentaerythritol tetrabehenate and the like.

  The surface tension of the wax of the present invention is preferably 35 mN / m or less, more preferably 30 mN / m or less, and particularly preferably 28 mN / m or less. Moreover, 20 mN / m or more is preferable and 24 mN / m or more is more preferable. If the surface tension is too large, waxes gather in the resin and the dispersibility of the wax in the resin becomes non-uniform, which tends to increase the fixing temperature of the toner. On the other hand, if it is too small, the dispersibility of the wax in the resin is improved, but at the same time, the precipitation of the wax on the toner surface increases. As a result, as described above, there is a tendency that the blocking resistance and the charging performance are deteriorated.

The half width of the melting peak of the wax of the present invention is preferably 20 ° C. or less, more preferably 15 ° C. or less, and particularly preferably 12 ° C. or less. If the half-width of the melting peak is too high, the wax does not melt quickly at the time of fixing, and thus a sufficient fixing reinforcing effect may not be exhibited. The lower limit of the half width of the melting peak is not limited, but is usually 2 ° C. or higher, preferably 5 ° C. or higher. Here, the half width of the melting peak of the wax means the peak width (° C.) at the position of half the melting peak height. In addition, the heat of fusion of the wax is preferably 80 J / g or more, more preferably 90 J / g or more. A high heat of fusion means that a large amount of heat is required to melt at the time of fixing, but if there is a heat amount to soften the binder resin, no problem occurs in melting of the wax. On the other hand, if the amount of heat of fusion is too small, the toner may block as a result of melting of the wax during storage of the toner or standby in the cartridge. In some cases, the toner is contaminated by melting of the wax before the toner passes through the developing process and moves to the fixing process. The upper limit of the heat of fusion is not limited, but is usually 300 J / g or less, preferably 250 J / g or less. Here, the heat of fusion of the wax means a value calculated from the area of the melting peak. In the wax of the present invention, the half width of the crystallization peak is preferably 25 ° C. or less, more preferably 20 ° C. or less. If the half width of the crystallization peak is within the above range, the wax melted at the time of fixing is quickly solidified, so that filming to the fixing roller does not occur and the high temperature offset property tends to be good. The lower limit of the full width at half maximum of the crystallization peak is not limited, but is usually 5 ° C or higher, preferably 10 ° C or higher. Here, the half width of the crystallization peak of the wax means the peak width (° C.) at the position of half the peak height.

In the present invention, the wax may be used alone or in combination. In order to improve fixability among these waxes, the melting point is preferably 110 ° C. or lower, more preferably 90 ° C. or lower, and particularly preferably 80 ° C. or lower. As a minimum of melting | fusing point, 40 degreeC or more is preferable, More preferably, it is 50 degreeC or more. If the melting point is too high, the effect of reducing the fixing temperature will be poor, and if the melting point is too low, problems may occur in the caking property and storage stability.
In the present invention, the amount of the wax is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and further preferably 5 parts by mass or more based on 100 parts by mass of the toner. Moreover, it is preferable that it is 40 mass parts or less, More preferably, it is 35 mass parts or less, More preferably, it is 30 mass parts or less. If the wax content in the toner is too low, performance such as high-temperature offset may not be sufficient. If it is too high, the anti-blocking property may be insufficient or the wax may leak from the toner and contaminate the device. There is a case to do.

  In the present invention, as a method of blending the wax in the polymerization method, it is preferable to previously disperse the wax in water with a volume average diameter of 0.01 μm to 2.0 μm. Furthermore, it is preferable that it is 1.0 micrometer or less, and it is especially preferable that it is 0.5 micrometer or less. Furthermore, in the emulsion polymerization aggregation method, it is preferable to add the wax dispersion dispersed in the above average diameter range during emulsion polymerization or in the aggregation step. In order to disperse the wax with a suitable dispersed particle size in the toner, it is preferable to use so-called seed polymerization in which the wax is added as a seed during emulsion polymerization. By adding as a seed, the wax is finely and uniformly dispersed in the toner, so that deterioration of the chargeability and heat resistance of the toner can be suppressed.

  In particular, in the emulsion polymerization aggregation method, the wax dispersion preferably contains the crystalline polymer. The amount of the crystalline polymer with respect to 100 parts by mass of the wax is preferably 0.1 to 100 parts by mass.

  In addition, a wax / long-chain polymerizable monomer dispersion obtained by previously dispersing a wax in a water-based dispersion medium with a long-chain polymerizable monomer such as stearyl acrylate is prepared in advance. The polymerizable monomer can also be polymerized in the presence of the body.

The toner of the present invention may be produced by any polymerization method such as a suspension polymerization method, an emulsion polymerization aggregation method, or a dissolution suspension method, and is not particularly limited.
In the present invention, as a method for producing a suspension polymerization toner, a coloring agent, a polymerization initiator, and, if necessary, a wax, a polar resin, a charge control agent, a crosslinking agent, etc. in the above-mentioned binder resin monomer. An additive is added to prepare a monomer composition that is uniformly dissolved or dispersed. This monomer composition is dispersed in an aqueous medium containing a dispersion stabilizer and the like. Preferably, granulation is performed by adjusting the stirring speed and time so that the droplets of the monomer composition have a desired toner particle size. Thereafter, polymerization is carried out by stirring to such an extent that the particle state is maintained and the sedimentation of the particles is prevented by the action of the dispersion stabilizer. These are collected by washing and filtration, and dried to obtain toner mother particles. Further, if necessary, toner can be obtained by external addition or the like.
As a production method of the emulsion polymerization aggregation method, polymer primary particles of a binder resin monomer obtained by emulsion polymerization, a colorant dispersion, a wax dispersion, etc. are prepared, and these are dispersed in an aqueous medium. By carrying out heating or the like, it undergoes an agglomeration step and an aging step. These are collected by washing and filtration, and dried to obtain toner mother particles. Further, if necessary, toner can be obtained by external addition or the like. In the present invention, in the aggregation step in the emulsion polymerization aggregation method, the polymer primary particles, the colorant particles, and if necessary, the charge control agent, the compounding component such as wax are mixed simultaneously or sequentially, Of the above components, that is, a polymer primary particle dispersion, a colorant particle dispersion, a charge control agent dispersion, and a wax fine particle dispersion, if necessary, are mixed to obtain a mixed dispersion. It is preferable from the viewpoint of the uniformity of the composition and the uniformity of the particle diameter.

The agglomeration treatment is usually performed in a tank equipped with a stirrer, but there are a heating method, a method of adding an electrolyte, a method of combining these, and the like. When polymer primary particles are agglomerated with stirring to obtain particle aggregates of the desired size, the particle size of the particle aggregates is controlled based on the balance between the agglomeration force between the particles and the shearing force due to agitation. However, the cohesive force can be increased by heating or adding an electrolyte. As an electrolyte when an electrolyte is added and agglomerated, either an organic salt or an inorganic salt may be used. Specifically, NaCl, KCl, LiCl, Na ₂ SO ₄ , K ₂ SO ₄ , Li ₂ SO _{4 are used. , MgCl 2, CaCl 2, MgSO} 4, CaSO 4, ZnSO 4, Al 2 (SO 4) 3, Fe 2 (SO 4) 3, CH 3 COONa, C 6 H 5 SO 3 Na and the like. Of these, inorganic salts having a divalent or higher polyvalent metal cation are preferred. The amount of electrolyte added varies depending on the type of electrolyte, target particle size, etc., but is preferably 0.05 parts by weight, more preferably 0.1 parts by weight or more, based on 100 parts by weight of the solid component of the mixed dispersion. . Moreover, 25 mass parts or less are preferable, 15 mass parts or less are more preferable, and 10 mass parts or less are especially preferable. When the addition amount is too small, the progress of the agglutination reaction is delayed, and there are problems such that fine powder of 1 μm or less remains after the agglomeration reaction or the average particle diameter of the obtained particle aggregate does not reach the target particle diameter. In some cases, if the amount is too large, rapid aggregation tends to occur and it becomes difficult to control the particle size, and the resulting aggregated particles may have problems such as inclusion of coarse powders or irregular shapes. When the aggregation is performed by adding an electrolyte, the aggregation temperature is 20 ° C. or higher, more preferably 30 ° C. or higher, and 70 ° C. or lower, more preferably 60 ° C. or lower. The aggregation temperature in the case of performing aggregation only by heating without using an electrolyte is usually in the temperature range of Tg-20 ° C to Tg, where Tg is the glass transition temperature of the polymer primary particles, and Tg-10 ° C to Tg. A range of −5 ° C. is preferable.

  The time required for agglomeration is optimized depending on the shape of the apparatus and the processing scale, but in order for the particle size of the toner particles to reach the target particle size, it is usually held at the above-mentioned predetermined temperature for at least 30 minutes. Is desirable. The temperature rise until reaching the predetermined temperature may be raised at a constant rate, or may be raised stepwise.

  On the surface of the particle aggregate after the above-described aggregation treatment, particles with resin fine particles attached or fixed can be formed as necessary. By attaching or fixing resin fine particles whose properties are controlled to the surface of the particle aggregate, the chargeability and heat resistance of the obtained toner may be improved, and the effects of the present invention can be further enhanced. .

When resin fine particles having a glass transition temperature higher than that of the polymer primary particles are used as the resin fine particles, it is preferable because blocking resistance can be further improved without impairing fixing properties. The volume average particle diameter of the resin fine particles is preferably 0.02 to 3 μm, more preferably 0.05 to 1.5 μm. As the resin fine particles, those obtained by emulsion polymerization of monomers similar to the polymerizable monomers used for the above-described polymer primary particles can be used.
The resin fine particles are usually used as a dispersion dispersed in water or a liquid mainly composed of water using a surfactant. However, when a charge control agent is added after the aggregation treatment, charge control is performed on the dispersion containing particle aggregates. It is preferable to add resin fine particles after adding the agent.

  In order to increase the stability of the particle aggregate obtained in the aggregation step, it is preferable to perform fusion in the aggregated particles in the aging step after the aggregation step. The temperature of the ripening step is preferably not less than Tg of the polymer primary particles, more preferably not less than 5 ° C higher than Tg, and preferably not more than 80 ° C higher than Tg, more preferably not less than 50 ° C higher than Tg. It is as follows. The time required for the aging process varies depending on the shape of the target toner, but after reaching the glass transition temperature of the polymer primary particles, the lower limit is 0.1 hour or more, preferably 1 hour or more, and the upper limit is It is desirable to hold for 10 hours or less, preferably 6 hours or less.

  In addition, it is preferable to add a surfactant or raise the pH value after the aggregation process, preferably before the aging process or during the aging process. As the surfactant used here, one or more emulsifiers can be selected from the emulsifiers that can be used when producing the polymer primary particles. In particular, the emulsifiers used when producing the polymer primary particles. It is preferable to use the same. Although the addition amount in the case of adding surfactant is not limited, Preferably it is 0.1 mass part or more with respect to 100 mass parts of solid components of a mixed dispersion, More preferably, it is 1 mass part or more, More preferably, it is 3 masses It is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and still more preferably 10 parts by mass or less. After the aggregation process, before the completion of the ripening process, by adding a surfactant or raising the pH value, it is possible to suppress aggregation of the particle aggregates aggregated in the aggregation process, In some cases, the generation of coarse particles can be suppressed. By heat treatment in the aging step, the polymer primary particles in the aggregate are fused and integrated, and the toner particle shape as the aggregate becomes close to a spherical shape. The particle aggregate before the aging step is considered to be an aggregate due to electrostatic or physical aggregation of the polymer primary particles, but after the aging step, the polymer primary particles constituting the particle aggregate are fused to each other. In addition, the shape of the toner particles can be made nearly spherical. According to such an aging process, by controlling the temperature and time of the aging process, the shape of the polymer primary particles is agglomerated, a potato type with advanced fusion, a spherical form with further fusion For example, various shapes of toner can be manufactured according to the purpose.

  The toner produced by the wet method is separated from the aqueous solvent, washed and dried, and subjected to an external addition treatment or the like, if necessary, for use as an electrostatic image developing toner. Although water is used as the liquid used for washing, it can be washed with an acid or alkali aqueous solution, and it is preferable to use an inorganic acid such as nitric acid, hydrochloric acid or sulfuric acid, or an organic acid such as citric acid. Moreover, it can also wash | clean with warm water or hot water, and these methods can also be used together. Through such a washing step, the suspension stabilizer, the emulsifier, the unreacted residual monomer and the like can be reduced and removed, which is preferable. In the washing step, the liquid to be washed is subjected to, for example, filtration, decantation, etc., so that the colored particles are made into a thick slurry or wet cake, and the operation for dispersing the toner by adding the liquid for washing to this is repeated. preferable. The colored particles after washing are preferably collected in the form of a wet cake in terms of handling in the subsequent drying step.

  In the drying process, a fluidized drying method such as a vibration type fluidized drying method or a circulation type fluidized drying method, an air flow drying method, a vacuum drying method, a freeze drying method, a spray drying method, a flash jet method, or the like is used. Operating conditions such as temperature, air volume, and degree of reduced pressure in the drying step are appropriately optimized based on the Tg of the colored particles, the shape, mechanism, size, etc. of the apparatus used.

To the toner particles of the present invention, externally added fine particles can be added as necessary to improve toner fluidity and charge control properties. Examples of such externally added fine particles include various inorganic or organic fine particles. Can be appropriately selected and used.
Inorganic fine particles include silicon carbide, boron carbide, titanium carbide, zirconium carbide, hafnium carbide, vanadium carbide, tantalum carbide, niobium carbide, tungsten carbide, chromium carbide, molybdenum carbide, calcium carbide, and other carbides, boron nitride, titanium nitride. , Various nitrides such as zirconium nitride, various borides such as zirconium boride, various oxides such as titanium oxide, calcium oxide, magnesium oxide, zinc oxide, copper oxide, aluminum oxide, cerium oxide, silica, colloidal silica, titanium Various titanate compounds such as calcium oxide, magnesium titanate and strontium titanate, phosphate compounds such as calcium phosphate, sulfides such as molybdenum disulfide, fluorides such as magnesium fluoride and fluorocarbon, aluminum stearate, stearin Calcium, zinc stearate, can be used various metal soaps such as magnesium stearate, talc, bentonite, various carbon black or conductive carbon black, magnetite, ferrite or the like. As the organic fine particles, fine particles such as styrene resin, acrylic resin, epoxy resin, and melamine resin can be used.

  Among these externally added fine particles, silica, titanium oxide, alumina, zinc oxide, various carbon blacks, conductive carbon blacks, and the like are preferably used. Further, the externally added fine particles are obtained by applying the surface of the inorganic or organic fine particles to a silane coupling agent, a titanate coupling agent, a silicone oil, a modified silicone oil, a silicone varnish, a fluorine silane coupling agent, a fluorine silicone oil, What has been subjected to surface treatment such as hydrophobization with a treating agent such as a coupling agent having an amino group or a quaternary ammonium base can also be used. Two or more kinds of the treatment agents can be used in combination.

  In the present invention, the externally added fine particles preferably have an average particle size of 0.001 μm or more, and more preferably 0.005 μm or more. Moreover, 3 micrometers or less are preferable and 1 micrometer or less is more preferable. The average particle diameter of the externally added fine particles can be determined by observation with an electron microscope. In addition, the externally added fine particles may be blended in a plurality of types having different particle diameters, or may be used in combination of two or more different types. The surface-treated and unsurface-treated particles may be used in combination or different. A surface-treated one can be used in combination, and a positively charged one and a negatively charged one can be used in appropriate combination.

  The content of the externally added fine particles is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, preferably 5 parts by mass or less, more preferably 100 parts by mass of the toner particles. The amount is desirably 3 parts by mass or less.

  Examples of the method for adding the externally added fine particles include a method using a high-speed stirrer such as a Henschel mixer, a method using an apparatus capable of applying a compressive shear stress, and the like.

  Further, inorganic fine powders such as magnetite, ferrite, cerium oxide, strontium titanate, and conductive titania can be added. The amount of these additives used may be appropriately selected depending on the desired performance, and is usually about 0.05 to 10 parts by mass with respect to 100 parts by mass of the toner particles.

  The toner for developing an electrostatic image of the present invention may be used in any form of a two-component developer using toner particles together with a carrier, or a magnetic or non-magnetic one-component developer not using a carrier. When used as a two-component developer, the carrier may be a magnetic substance such as iron powder, magnetite powder, ferrite powder or the like, or a known material such as a resin-coated surface or a magnetic carrier. As the coating resin of the resin coating carrier, generally known styrene resin, acrylic resin, styrene acrylic copolymer resin, silicone resin, modified silicone resin, fluororesin, or a mixture thereof can be used.

  The volume average particle size of the toner of the present invention is preferably 3 μm or more, and more preferably 4 μm or more. Moreover, 15 micrometers or less are preferable, Furthermore, 10 micrometers or less are more preferable, and 8 micrometers or less are especially preferable. The toner of the present invention has a 50% circularity measured by using a flow particle image analyzer FPIA-3000, preferably 0.90 or more, more preferably 0.92 or more, still more preferably 0.00. 94 or more, preferably 0.98 or less, more preferably 0.96 or less. If the 50% circularity is too small, it may cause a decrease in image density due to poor charging due to poor adhesion of the external additive to the colored particles, and if too large, it may result in poor cleaning due to the colored particle shape. is there.

  The glass transition point Tg by the DSC method of the toner of the present invention is preferably 40 ° C. or higher, more preferably 50 ° C. or higher, preferably 80 ° C. or lower, more preferably 70 ° C. or lower. When Tg is in the above range, it is desirable because the storage stability and fixing property of the toner are improved.

Specific examples of the present invention will be described below in more detail with reference to examples. However, the present invention is not limited to these examples unless it exceeds the gist.
In the following examples, “part” means “part by mass”. Various measurements in the present invention were measured by the following methods.

<Volume average diameter measurement of wax particles and polymer primary particles>
The volume average diameter of particles with a volume average diameter of less than 1 micron is measured using Nikkiso Co., Ltd. model Microtrac Nanotrac150 (hereinafter referred to as Nanotrac) and its analysis software Microtrac Particle Analyzer Ver10.1.2-019EE. Measurement was performed by the method described in the instruction manual under the measurement conditions of 0.5 μS / cm of ion-exchanged water as a solvent, solvent refractive index: 1.333, measurement time: 600 seconds, and the number of measurements: one. Other setting conditions were particle refractive index: 1.59, transparency: transmission, shape: true sphere, density: 1.04.

<Volume median diameter measurement (Dv50)>
The volume median diameter (Dv50) of particles with a volume median diameter (Dv50) of 1 micron or more is measured using the Beckman Coulter Multisizer III (aperture diameter 100 μm: hereinafter abbreviated as Multisizer). Using II as a dispersion medium, the dispersion was dispersed so that the dispersoid concentration was 0.03%.

<Measurement of viscosity of colored dispersion>
For measurement of the viscosity, a TVE-20 viscometer manufactured by TOKIMEC was used. The measurement temperature was 25 ° C., and a cone plate type jig was used as a measurement tool (E-type viscometer). The number of revolutions was usually 100 rpm, and in the case of high viscosity, the measurement was performed under the condition of the number of revolutions of 10 rpm.

<Evaluation of particle settling of colorant dispersion>
The sedimentation acceleration test was performed at room temperature using a centrifuge (manufactured by Hagitec Co., Ltd., CN-2060), and was ranked as follows. Desirably, it is more than ○. The sedimentation vessel was 50 ml, charged with 30 ml of the colorant dispersion, and the centrifugation conditions were 5000 rpm for 5 minutes. The evaluation value is obtained by measuring the sedimentation height from the bottom of the container when all particles settled by sufficient centrifugation in advance (100 mass% sedimentation), and the ratio of each to the measured height. This is expressed as
A: The amount of precipitated particles is less than 20% by mass (very low sedimentation)
○: Amount of precipitated particles 20 mass% or more and less than 40 mass% (sedimentation property is small)
Δ: Amount of precipitated particles 40% by mass or more and less than 60% by mass (sedimentation is slightly high, but there is no practical problem)
×: Amount of precipitated particles of 60% by mass or more (sedimentation property is large and cannot be used)

<Evaluation of re-aggregation of colorant dispersion>
After the colorant dispersion was manufactured, the dispersion 1L was weighed in a plastic container and allowed to stand as it was, and after 48 hours, the container was shaken up and down 10 times, and then the ratio of the particle size of 0.972 μm or more in the volume distribution of the colorant particles Pv (%) was measured again and evaluated by taking a ratio between the value and the value immediately after production, and was ranked as follows. Desirably, it is more than ○.
A: Increase ratio is less than 1.2 times (reaggregation property is very small)
○: Increase ratio is 1.2 times or more and less than 2 times (reaggregation property is small)
Δ: Increase ratio is 2 times or more and less than 3 times (Re-aggregation is slightly high, but there is no big problem in actual use)
×: Increase ratio is 3 times or more (high re-aggregation property and unbearable)

<Evaluation of toner particle size distribution and fine powder amount>
The volume average particle size (Dv50) was calculated using the Multisizer II described in the text. On the other hand, the ratio (%) of the cumulative volume distribution of particles smaller than 3 μm with respect to the overall particle size distribution was defined as toner fine powder. When the above-described FPIA 3000 is used, the amount of fine powder can be easily calculated. The amount of fine powder is preferably less because the toner charge becomes non-uniform, and it was ranked as follows, and ◯ and Δ were acceptable.
○: Less than 1.5% (less fine powder)
Δ: 1.5% or more and less than 3% (a lot of fine powder)
X: 3% or more (there is a lot of fine powder and cannot be used)

<Charging rise evaluation method>
A sample in which 0.4 g of toner was mixed with 9.6 g of a magnetic carrier (ferrite carrier F150 manufactured by Powdertech) was placed in a glass sample bottle and shaken using a reciprocating shaker (NR-1 manufactured by Taitec). One minute after the start of shaking, 0.1 g of the sample was weighed from the sample bottle and placed in a mesh case. The mesh case was fitted into a predetermined position inside a blow-off powder charge measuring device (TYPE TB-200 manufactured by Toshiba Chemical Corporation), and the charge amount of the toner was measured. From the sample shaking value for 1 minute, the toner charge rising (μC / g) was evaluated.

<Live-action evaluation>
Using a non-magnetic one-component contact development type full-color printer (ColorPage PrestoN4 manufactured by Casio Co., Ltd.), up to 6000 sheets were repeatedly photographed, and single-color image evaluation and full-color image evaluation were performed.

<Evaluation of image density>
The image density was measured with a reflection spectral densitometer (X-rite 504, manufactured by SDG Corporation) on the solid print portion of the print sample obtained by the above-mentioned actual image evaluation. Image density was ranked as follows.
○: 1.5 or more (high concentration)
X: Less than 1.5 (concentration is low)

<Evaluation of fog>
The fog was evaluated by measuring a difference in hunter whiteness using a colorimeter (ZE2200, manufactured by Nippon Denshoku). After continuous printing of 10,000 sheets at room temperature and normal humidity (temperature 25 ° C, relative humidity 55%, hereinafter referred to as NN environment), one day at high temperature and high humidity (temperature 28 ° C, relative humidity 85%, hereinafter referred to as HH environment). Printed after being allowed to stand. In this state, paper fog was measured on the paper before and after printing. The fog values were ranked as follows, and Δ or higher was regarded as acceptable.
A: Less than 0.5 (fogging is very small)
○: 0.5 or more and less than 1.0 (slight fogging)
Δ: 1.0 or more and less than 1.5 (less fogging)
×: 1.5 or more (a lot of fog)
Hunter whiteness W (L * a * b *) = 1 0 0-[(1 0 0-L *) 2
+ A * 2 + b * 2] 1/2

<Evaluation of afterimage>
In the above-mentioned actual image evaluation, a solid image is printed in the NN environment, and the image density of the tip portion and the image density of the portion printed after two rotations from the developing roller are respectively measured with X-rite 938 (manufactured by X-Rite). Measurements were made to determine the ratio (%) of the image density after two rounds to the tip. The ranking was as follows.
A: No problem at all (98% or more)
○: Level that can be used although there is a slight difference in image density (95% or more and less than 98%)
Δ: Level at which it can be recognized that there is a slight difference in image density (85% or more and less than 95%)
X: Level with a clear difference in image density (less than 85%)

<Evaluation of dirt>
In the actual image evaluation, the stain on the image was visually observed and judged from sensory evaluation according to the following criteria. △ or more was accepted.
A: No dirt at all
○: Slightly dirty but usable level
Δ: Partially dirty
X: Dirt can be clearly confirmed partially or entirely.

<Preparation of Colorant Dispersion A>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 (HLB value 15.3, polyoxyethylene lauryl ether having a cloud point of 98 ° C.)) 20 parts relative to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. The volume median diameter Dv50 of the particles in the dispersion after premixing was about 90 μm. The premix solution was supplied as a raw material slurry to a wet bead mill equipped with a rotating screen (bead separation mesh separator) as shown in FIG. 1, and circulated and dispersed in the configuration shown in FIG. Note that zirconia beads (true density of 6.0 g / cm ³ ) having a diameter of 120 mmφ, a separator diameter of 60 mmφ, and a diameter of 100 μm (0.1 mm) were used as dispersion media. Since the effective internal volume of the stator is about 0.5 liters and the media filling volume is 0.35 liters, the media filling rate is 70%. The premix slurry was supplied from a supply port at a supply speed of about 54 liters / hr with a non-pulsating metering pump, with the rotor rotating speed kept constant (the peripheral speed of the rotor tip was about 7 m / sec). During operation, cooling water at about 10 ° C. was circulated from the jacket to obtain a magenta colorant dispersion A having a Dv1 diameter of 0.13 μm and a viscosity of 20 cP. As a result, it was possible to obtain a dispersion excellent in particle sedimentation and prevention of reaggregation. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion B>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 123P (HLB value 16.9, cloud point> 100 ° C. polyoxyethylene lauryl ether)) (20 parts with respect to the pigment), 76 parts of ion-exchanged water having an electric conductivity of 2 μS / cm was added and predispersed to obtain a pigment premix solution. Dispersion was performed in the same manner as for Colorant Dispersion A to obtain a magenta colorant Dispersion B having a Dv1 diameter of 0.12 μm and a viscosity of 110 cP. As a result, a dispersion particularly excellent in preventing particle sedimentation could be obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion C>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 420 (HLB value 13.6, polyoxyethylene oleyl ether having a cloud point of 91 ° C.)) 20 parts relative to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as for Colorant Dispersion A, and Magenta Colorant Dispersion C having a Dv1 diameter of 0.16 μm and a viscosity of 40 cP was obtained. As a result, a dispersion particularly excellent in preventing reaggregation could be obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion D>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), nonionic surfactant (manufactured by Kao Corporation, Emulgen 1118S-70 (HLB value 16.4, cloud point> 100 ° C. polyoxyethylene alkyl ether)) 4 parts (20 parts with respect to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as for Colorant Dispersion A to obtain a magenta colorant Dispersion D having a Dv1 diameter of 0.14 μm and a viscosity of 60 cP. As a result, it was possible to obtain a dispersion excellent in particle sedimentation and re-aggregation prevention. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion E>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 (HLB value 15.3, polyoxyethylene lauryl ether having a cloud point of 98 ° C.)) 20 parts to pigment), anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen S20A (sodium dodecylbenzenesulfonate)) 0.04 part (0.2 part to pigment), conductivity 2 μS About 76 parts of ion-exchanged water / cm was added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as for Colorant Dispersion A to obtain a magenta colorant Dispersion E having a Dv1 diameter of 0.12 μm and a viscosity of 100 cP. As a result, a dispersion particularly excellent in preventing particle sedimentation could be obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion F>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 (HLB value 15.3, polyoxyethylene lauryl ether having a cloud point of 98 ° C.)) 20 parts relative to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. The volume cumulative 50% diameter Dv50 of the particles in the dispersion after premixing was about 90 μm. The premix solution was supplied as a raw material slurry to a wet bead mill equipped with a rotating screen (bead separation mesh separator) as shown in FIG. 1, and circulated and dispersed in the configuration shown in FIG. Note that zirconia beads (true density 6.0 g / cm ³ ) having a diameter of 120 mmφ, a separator diameter of 60 mmφ, and a diameter of 100 μm were used as a dispersion medium. Since the effective internal volume of the stator is about 0.5 liters and the filling volume of the media is 0.40 liters, the media filling rate is 80%. The premix slurry was supplied from the supply port at a supply speed of about 45 liters / hr with a non-pulsating metering pump with the rotor rotating speed kept constant (the peripheral speed at the rotor tip was about 10 m / sec). In operation, cooling water at about 10 ° C. was circulated from the jacket to obtain a magenta colorant dispersion F having a Dv1 diameter of 0.09 μm and a viscosity of 350 cP. As a result, a dispersion having deteriorated reaggregation property was obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion G>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Color Co., Ltd., permanent carmine 3810), 4 parts of nonionic surfactant whose hydrophilic group is not polyoxyethylene (manufactured by Kao Corporation, Rhedol MS165V (monoglyceride stearate having an HLB value of 11)) 20 parts), and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm was added for preliminary dispersion. However, the pigment premix solution could not be obtained because the solubility of the dispersant was poor and the pigment did not get wet without getting wet. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion H>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), nonionic surfactant whose hydrophobic group is not an alkyl ether (manufactured by Kao Corporation, Emanon 1112 (polyethylene glycol monolaurate having an HLB value of 13.7)) 4 Part (20 parts with respect to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as for Colorant Dispersion A, and Magenta Colorant Dispersion H having a Dv1 diameter of 0.15 μm and a viscosity of 120 cP was obtained. As a result, a dispersion excellent in preventing particle sedimentation could be obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion I>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. Pigment Red 269 (manufactured by Sanyo Color Co., permanent carmine 3810), nonionic surfactant (manufactured by Kao Co., Ltd., Emulgen 105 polyoxyethylene lauryl ether having an HLB value of 9.7) 4 parts (20% to pigment) Part) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed. However, the pigment premix solution could not be obtained because the solubility of the dispersant was poor and the pigment did not get wet without getting wet. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion J>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Color Co., Ltd., permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 150 (HLB value 18.4, cloud point> 100 ° C. polyoxyethylene lauryl ether)) (20 parts with respect to the pigment), 76 parts of ion-exchanged water having an electric conductivity of 2 μS / cm was added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as for Colorant Dispersion A, and Magenta Colorant Dispersion J having a Dv1 diameter of 0.11 μm and a viscosity of 80 cP was obtained. As a result, a dispersion excellent in preventing reaggregation could be obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion K>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 109P (HLB value 13.6, polyoxyethylene lauryl ether having a cloud point of 83 ° C.)) 20 parts relative to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was performed in the same manner as for Colorant Dispersion A, and Magenta Colorant Dispersion K having a Dv1 diameter of 0.14 μm and a viscosity of 60 cP was obtained. As a result, it was possible to obtain a dispersion excellent in particle sedimentation and re-aggregation prevention. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion L>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Pigment Co., permanent carmine 3810), 2 parts of anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen S20A (sodium dodecylbenzenesulfonate)), 10 parts of pigment 78 parts of ion-exchanged water having an electric conductivity of 2 μS / cm was added and predispersed to obtain a pigment premix solution. Dispersion was performed in the same manner as for Colorant Dispersion A, and Magenta Colorant Dispersion L having a Dv1 diameter of 0.11 μm and a viscosity of 250 cP was obtained. As a result, a dispersion excellent in preventing particle sedimentation could be obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion M>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. Pigment Red 269 (manufactured by Sanyo Color Co., permanent carmine 3810), nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 (HLB value 15.3, polyoxyethylene lauryl ether having a cloud point of 98 ° C.)) 1.8 Part (9 parts with respect to the pigment) and 78 parts of ion-exchanged water having an electric conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was performed in the same manner as for Colorant Dispersion A, and Magenta Colorant Dispersion M having a Dv1 diameter of 0.20 μm and a viscosity of 550 cP was obtained. As a result, a dispersion having deteriorated particle sedimentation and re-aggregation properties was obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion N>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 (HLB value 15.3, polyoxyethylene lauryl ether having a cloud point of 98 ° C.)) 20 parts relative to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as Dispersant A, except that zirconia beads having a diameter of 0.05 mm (true density 6.0 g / cm ³ ) were used as the dispersion medium, and the Dv1 diameter was 0.08 μm and the viscosity was A magenta colorant dispersion N of 650 cP was obtained. As a result, a dispersion having deteriorated particle sedimentation properties was obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion O>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 (HLB value 15.3, polyoxyethylene lauryl ether having a cloud point of 98 ° C.)) 20 parts relative to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as Dispersant A, except that zirconia beads having a diameter of 0.5 mm (true density 6.0 g / cm ³ ) were used as the dispersion medium, and the Dv1 diameter was 0.14 μm and the viscosity was 30
A magenta colorant dispersion O of cP was obtained. As a result, a dispersion particularly excellent in preventing reaggregation could be obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion P>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 (HLB value 15.3, polyoxyethylene lauryl ether having a cloud point of 98 ° C.)) 20 parts relative to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as Dispersant A, except that zirconia beads having a diameter of 1.0 mm (true density 6.0 g / cm ³ ) were used as the dispersion medium. The Dv1 diameter was 0.16 μm and the viscosity was A magenta colorant dispersion P of 30 cP was obtained. As a result, it was possible to obtain a dispersion excellent in particle sedimentation and prevention of reaggregation. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion Q>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 (HLB value 15.3, polyoxyethylene lauryl ether having a cloud point of 98 ° C.)) 20 parts relative to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as Dispersant A, except that zirconia beads having a diameter of 1.2 mm (true density 6.0 g / cm ³ ) were used as the dispersion medium, and the Dv1 diameter was 0.18 μm and the viscosity was A 220 mP magenta colorant dispersion Q was obtained. As a result, a dispersion having deteriorated particle sedimentation properties was obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion R>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 (HLB value 15.3, polyoxyethylene lauryl ether having a cloud point of 98 ° C.)) 20 parts relative to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as Dispersant A, except that glass beads having a diameter of 0.5 mm (true density: 2.5 g / cm ³ ) were used as the dispersion medium, and the Dv1 diameter was 0.21 μm and the viscosity was A 300 cP magenta colorant dispersion R was obtained. As a result, a dispersion having deteriorated particle sedimentation properties was obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of Colorant Dispersion S>
A naphthol azo pigment C having a true density of 1.5 g / cm ³ is placed in a stirrer vessel equipped with a propeller blade.
. I. 20 parts of Pigment Red 269 (manufactured by Sanyo Dye, permanent carmine 3810), 4 parts of nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 (HLB value 15.3, polyoxyethylene lauryl ether having a cloud point of 98 ° C.)) 20 parts relative to the pigment) and 76 parts of ion-exchanged water having a conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. Dispersion was carried out in the same manner as Dispersant A, except that glass beads having a diameter of 1.0 mm (true density 2.5 g / cm ³ ) were used as the dispersion medium, and the Dv1 diameter was 0.25 μm and the viscosity was A magenta colorant dispersion S of 550 cP was obtained. As a result, a dispersion having deteriorated particle sedimentation and re-aggregation properties was obtained. Dispersant properties and dispersion results are summarized in Table 1.

<Preparation of wax dispersion A>
Alkyl-modified silicone wax (thermal characteristics: melting point 77 ° C., heat of fusion 97 J / g, melting peak half width 10.9 ° C., crystallization peak half width 17.0 ° C.) 30 parts, anionic surfactant (Daiichi Kogyo Seiyaku) 0.3 parts of Neogen S20A) and 70 parts of demineralized water were heated to 90 ° C. and stirred with a disperser for 10 minutes. Next, this dispersion was heated to 100 ° C., emulsification was started under a pressure condition of about 15 MPa using a homogenizer (manufactured by Gorin Co., Ltd., 15-M-8PA type), and the volume average particle size was measured while measuring with a particle size distribution meter. Was dispersed to about 0.2 μm to prepare a wax dispersion A.

<Production of polymer primary particle emulsion>
In a reactor equipped with a stirrer, a heating / cooling device, and a concentrating device, 365 parts of demineralized water and 45 parts of wax dispersion A were placed and heated to 90 ° C. While maintaining the reaction solution at 90 ° C. under a nitrogen stream, the following raw material mixture was added to the reactor over 5 hours, and emulsion copolymerization was performed using wax particles as seeds. Subsequently, it cooled and the milky white polymer primary particle emulsion A (solid content of about 19 mass%) of the styrene-butyl acrylate-acrylic acid type copolymer was obtained. When the volume average particle diameter of the binder resin fine particles contained in the obtained emulsion was measured by UPA, the volume average particle diameter (arithmetic average diameter based on volume) was 0.26 μm. The obtained emulsion polymer has a THF-soluble matter having a mass-average molecular weight of about 83,000, a number-average molecular weight of 19,000, a peak molecular weight of about 43,000, and a THF-insoluble matter of 26 mass%. , Sp was 114 ° C., Tg was 56 ° C., and the acid value was 9 mgKOH / g.

[Raw material mixture]
Styrene 79 parts by weight Butyl acrylate 21 parts by weight Acrylic acid 3 parts by weight 1,6-hexanediol diacrylate 0.7 parts by weight Trichlorobromomethane (chain transfer agent) 1.3 parts by weight 10% anionic surfactant (neogen SC) Aqueous solution 12 parts by mass 8% hydrogen peroxide aqueous solution 43 parts by mass 8% ascorbic acid aqueous solution 43 parts by mass

<Manufacture of toner M1>
5 parts of Colorant Dispersion A is added to 100 parts of Polymer Primary Particle Emulsion A, and an aqueous aluminum sulfate solution (0.5 parts as aluminum sulfate) is added dropwise with stirring with a disperser, and the mixture is stirred for 30 minutes. The temperature was raised to 50 ° C. and held for 1 hour, and the mixture was further agglomerated by raising the temperature to 52 ° C. with stirring. When the volume average particle diameter as an aggregate was 7 μm as measured by Multisizer III, 3 parts of an anionic surfactant (Neogen S20A) 10% aqueous solution was added.
Thereafter, 10 parts of an aqueous dispersion (resin solid content 20% by mass) of styrene / butyl acrylate polymer fine particles A (Tg 80 ° C., volume average particle size 0.14 μm measured by UPA) was added as encapsulated resin fine particles. . Subsequently, the temperature was raised to 97 ° C. over 50 minutes with stirring, and this temperature was maintained for 1.5 hours to fuse the aggregate and the encapsulated resin fine particles attached to the surface thereof. Subsequently, heating and stirring were continued until the average circularity was 0.944 as measured by FPIA2100. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry. The obtained slurry was extracted and subjected to suction filtration with an aspirator using filter paper of type 5 C (No5C manufactured by Toyo Roshi Kaisha, Ltd.). The cake remaining on the filter paper is transferred to a stainless steel container having an internal volume of 10 L equipped with a stirrer (propeller blade), and 8 kg of ion exchange water having an electric conductivity of 1 μS / cm is added and stirred uniformly at 50 rpm. Thereafter, stirring was continued for 30 minutes.
Thereafter, the filter paper was suction filtered with an aspirator again using Type 5 C (Toyo Filter Paper No. 5C) filter paper, and the solid matter remaining on the filter paper was again equipped with a stirrer (propeller blade) and had an electrical conductivity of 1 μS / cm. It was transferred to a container with an internal volume of 10 L containing 8 kg of ion-exchanged water, and uniformly dispersed by stirring at 50 rpm and kept stirring for 30 minutes. When this process was repeated 5 times, the electrical conductivity of the filtrate was 2 μS / cm. The solid matter obtained here was spread on a stainless bat so as to have a height of 20 mm, and dried in a blow dryer set at 40 ° C. for 48 hours to obtain toner mother particles. In addition, when the thickness of the capsule layer was measured from the cross-sectional photograph of this mother particle (cross-sectional photograph taken with a transmission electron microscope microscope Hitachi H7500 system), the average was about 0.1 μm.
With respect to 100 parts of the obtained magenta toner base particles, 0.5 part of silica fine particles A having an average primary particle diameter of 50 nm hydrophobized with dimethylsilicone oil and an average primary particle diameter hydrophobized with dimethylsilicone oil Then, 2.0 parts of 12 nm silica fine particles B were added, warm water of 45 ° C. was passed through the outer jacket, and the mixture was stirred and mixed with a temperature-controlled Henschel mixer to obtain a magenta toner M1.

<Manufacture of toner M2>
In toner production M1, except that the colorant dispersion was changed to B, toner mother particles were obtained in the same manner, and thereafter external addition was carried out in exactly the same manner as in M1 to obtain magenta toner M2.

<Manufacture of toner M3>
In toner production M1, except that the colorant dispersion was changed to C, toner mother particles were obtained in the same manner, and then external addition was carried out in the same manner as in M1 to obtain magenta toner M3.

<Manufacture of toner M4>
In toner production M1, except that the colorant dispersion was changed to D, toner mother particles were obtained in the same manner, and thereafter external addition was carried out in exactly the same manner as in M1 to obtain magenta toner M4.

<Manufacture of toner M5>
In toner production M1, except that the colorant dispersion was changed to E, toner mother particles were obtained in the same manner, and then external addition was carried out in exactly the same manner as in M1 to obtain magenta toner M5.

<Production of Toner M6>
Toner mother particles were produced in exactly the same manner as in toner production M1, except that the colorant dispersion was changed to H. However, fine powder was formed from the beginning of aggregation, and finally the fine powder amount was 1.5% or more and less than 3%. Although magenta toner M6 was obtained, the subsequent evaluation was stopped.

<Production of Toner M7>
Toner mother particles were produced in exactly the same manner except that the colorant dispersion was changed to J in toner production M1. However, fine powder was formed from the beginning of aggregation, and finally the fine powder amount became 1.5% or more and 3% or less. Although magenta toner M7 was obtained, the subsequent evaluation was stopped.

<Manufacture of Toner M8>
Toner mother particles were produced in exactly the same manner as in toner production M1, except that the colorant dispersion was changed to K. However, although encapsulated resin fine particles were added, they did not adhere to the surface, and the aggregates formed fine powders as they were, and finally the fine powder amount became 1.5% or more and less than 3%. Although magenta toner M8 was obtained, the subsequent evaluation was stopped.

<Production of Toner M9>
In toner production M1, except that the colorant dispersion was changed to L, toner mother particles were obtained in the same manner, and then external addition was carried out in exactly the same manner as in M1 to obtain magenta toner M9.

<Production of Toner M10>
In toner production M1, except that the colorant dispersion was changed to O, toner mother particles were obtained in the same manner, and then external addition was carried out in exactly the same manner as in M1 to obtain magenta toner M10.

<Production of Toner M11>
In toner production M1, except that the colorant dispersion was changed to P, toner mother particles were obtained in the same manner, and thereafter external addition was carried out in exactly the same manner as in M1 to obtain magenta toner M11.

<Production of Toner M12>
In the toner production M1, toner base particles were produced in exactly the same manner except that the colorant dispersion was changed to Q. However, fine powder was formed from the beginning of aggregation, and finally the fine powder amount exceeded 3%.

<Production of Toner M13>
Toner mother particles were produced in exactly the same manner as in toner production M1, except that the colorant dispersion was changed to R. However, fine powder was formed from the beginning of aggregation, and finally the fine powder amount exceeded 3%.

[Example 1]
The charge rising value of the externally added toner of the toner M1 was measured and found to be −25 μC / g. The toner was packed in a cartridge for printing, and image evaluation was performed. As a result, a toner with good image density, paper fog, afterimage and stain was obtained, and in particular, a result of improved fog, afterimage and stain was obtained. The results are summarized in Table 2.

[Example 2]
The charge rising value of the externally added toner of the toner M2 was measured and found to be −22 μC / g. The toner was packed in a cartridge for printing, and image evaluation was performed. As a result, a toner excellent in image density, paper fog, and dirt was obtained. The results are summarized in Table 2.

[Example 3]
The charge rising value of the externally added toner of the toner M3 was measured and found to be −24 μC / g. The toner was packed in a cartridge for printing, and image evaluation was performed. As a result, a toner with good image density, paper fog, afterimage and stain was obtained, and in particular, the result of improved fog was obtained. The results are summarized in Table 2.

[Example 4]
The charge rising value of the externally added toner of Toner M4 was measured and found to be −23 μC / g. The toner was packed in a cartridge for printing, and image evaluation was performed. As a result, a toner excellent in image density, paper fog, afterimage and stain was obtained. The results are summarized in Table 2.

[Example 5]
The charge rising value of the externally added toner of Toner M5 was measured and found to be −20 μC / g. The toner was packed in a cartridge for printing, and image evaluation was performed. As a result, a good toner was obtained for image density, paper fog, and afterimage. The results are summarized in Table 2.

[Example 6]
The charge rising value of the externally added toner of the toner M11 was measured and found to be −25 μC / g. The toner was packed in a cartridge for printing, and image evaluation was performed. As a result, a toner with good image density, paper fog, afterimage and stain was obtained, and in particular, a result of improved fog, afterimage and stain was obtained. The results are summarized in Table 2.

[Comparative Example 1]
The charge rising value of the externally added toner of Toner M9 was measured and found to be −10 μC / g. The toner was packed in a cartridge for printing, and image evaluation was performed. As a result, image density,
Paper toner, afterimages, and smudges were deteriorated. The results are summarized in Table 2.

[Comparative Example 2]
The charge rising value of the externally added toner of the toner M12 was measured and found to be -12 μC / g. The toner was packed in a cartridge for printing, and image evaluation was performed. As a result, the toner was deteriorated in image density, paper fog, afterimage and stain. The results are summarized in Table 2.

[Comparative Example 3]
The charge rising value of the externally added toner of the toner M13 was measured and found to be -15 μC / g. The toner was packed in a cartridge for printing, and image evaluation was performed. As a result, the toner was deteriorated in image density, paper fog, afterimage and stain. The results are summarized in Table 2.

Claims (12)

A method for producing a toner using a colorant dispersion comprising a dispersion medium and a magenta colorant, wherein the colorant has a volume median diameter Dv1 (μm) and a viscosity η at a temperature of 25 ° C. (CP) satisfies the following formula (1): a method for producing an electrostatic charge image developing toner (Dv1 is measured by a dynamic light scattering method, and the volumetric particle size distribution cumulative curve of the colorant is 50%. Represents the particle size of the point.
^{η <41360 × (Dv1) 2} - 12800 × Dv1 + 1145 ···· (1)   The method for producing a toner for developing an electrostatic charge image according to claim 1, wherein the dispersion medium contains at least a nonionic surfactant.   The method for producing a toner for developing an electrostatic charge image according to claim 2, wherein the hydrophilic group portion of the nonionic surfactant is polyoxyethylene.   4. The method for producing a toner for developing an electrostatic charge image according to claim 2, wherein the hydrophobic group portion of the nonionic surfactant is an alkyl ether.   5. The method for producing a toner for developing an electrostatic charge image according to claim 2, wherein the nonionic surfactant has an HLB value of 10 or more and 17 or less.   6. The method for producing a toner for developing an electrostatic charge image according to claim 2, wherein the clouding point of the nonionic surfactant is 90 ° C. or higher.   7. The method for producing a toner for developing an electrostatic charge image according to claim 2, wherein the amount of the nonionic surfactant is 10 parts by mass or more based on 100 parts by mass of the magenta colorant. The volume median diameter Dv1 (μm) of the magenta colorant in the colorant dispersion is 0.1 ≦ Dv1.
The method for producing a toner for developing an electrostatic image according to claim 1, wherein ≦ 0.16 is satisfied.   The magenta colorant is C.I. I. The method for producing a toner for developing an electrostatic charge image according to claim 1, wherein the toner is Pigment Red 269.   A cylindrical stator, a colorant dispersion supply port and a colorant dispersion discharge port provided at one end of the stator, a medium filled in the stator, and a colorant dispersion supplied from the supply port are stirred and mixed. And a rotor that is connected to a discharge passage inlet that communicates with the discharge port and rotates integrally with the rotor, or rotates independently of the rotor. 10. The method for producing a toner for developing an electrostatic charge image according to claim 1, which is obtained by using a wet mill comprising a separator which is separated into a dispersion and discharges the colorant dispersion from an outlet.   The method for producing a toner for developing an electrostatic charge image according to claim 10, wherein the diameter of the medium is 0.1 mm or more and 1 mm or less. The method of producing an electrostatic charge image developing toner according to claim 10 or 11, wherein the material of the media is ZrO _2.