JP2011064867A - Toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner which does not occur density irregularity or image deletion even when causing a drastic change in the use environment. <P>SOLUTION: The toner includes toner particles containing a binder resin, a colorant and a release agent, and hydrophobic inorganic fine particles, and is characterized in that: the hydrophobic inorganic fine particles are surface-treated with silicone oil (A) and then surface-treated with a silane compound and/or a silazane compound; the toner particles are obtained by an emulsion aggregation method; and in the toner particles, the proportion in number of particles having a circle-equivalent diameter of 0.25 μm or more and less than 1.98 μm measured by a flow-type particle image measurement device having an image processing resolution of 512×512 pixels (0.19 μm×0.19 μm per one pixel) to particles having a circle-equivalent diameter of 0.25 μm or more and less than 39.5 μm is 1.0 number% or more and 30.0 number% or less. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a toner used in an image forming method such as an electrophotographic method, an electrostatic printing method, and a toner jet method.

  Recent technical directions of image forming apparatuses include high definition, high quality, and high image quality, and reducing the average particle diameter of toner is one of effective means (see, for example, Patent Document 1). For example, as a method for intentionally controlling the toner shape and particle size, a method for producing toner particles using an emulsion aggregation method can be mentioned. This method generally produces a dispersion of resin fine particles, while preparing a dispersion of colorant fine particles in which a colorant is dispersed in a solvent, and mixes the dispersion of resin fine particles and the dispersion of colorant fine particles, Toner particles are obtained by forming an aggregate of fine particles corresponding to a desired toner particle diameter and then fusing and coalescing the fine particle aggregates by heating. Therefore, the material selectivity is wide and the shape, particle size, particle size distribution, and surface structure of the toner particles can be controlled.

  However, not all of these resin and colorant fine particles are involved in the formation of aggregates, and some of them are present as fine particles (hereinafter sometimes referred to as free fine particles). The amount of free fine particles can be reduced by optimizing the toner material and adjusting the manufacturing process, but it has not been completely eliminated. Of these free fine particles, polyester resin fine particles are particularly likely to absorb moisture and are easily affected by environmental humidity. Therefore, if they are present as fine particles in the toner, they are likely to cause various problems.

  In particular, cartridge-type printers are becoming more compact and can be installed anywhere, so that they are used in various environments and are required to exhibit stable performance when used in various environments. For example, if a cartridge that has been stored for a long time in a high-temperature and high-humidity environment without air conditioning equipment is brought into a room with air conditioning equipment and printed immediately, it will be adsorbed by the air and toner with a high water content in the toner container Moisture that has been cooled may be rapidly cooled and condensed. If condensed moisture exists in the toner, toner aggregates are formed with the moisture as the core, and when a uniform image pattern with a density such as a halftone is output, the size is about several mm to several tens of mm. In some cases, spot-like “density unevenness” occurs.

  On the other hand, the polyester resin fine particles released from the toner particles have high adhesion to the photoconductor and are difficult to be transferred onto a transfer material such as paper. Easy to accumulate in contact charging member. If left in a high-temperature, high-humidity environment for a long time in this state, the polyester resin microparticles accumulated on the contact charging member adsorb moisture, thereby reducing the resistance on the surface of the photoconductor and disturbing the latent image on the photoconductor. The phenomenon of “image flow” is likely to occur.

  In order to reduce the influence of toner moisture absorption, studies have been made to include hydrophobic inorganic fine particles in the toner.

  Patent Document 2 discloses a negatively charged negative electrode characterized by containing a negatively charged silicic acid fine powder that has been treated with hexamethyldisilazane or a silane coupling agent and then treated with silicone oil, and a toner. An electrophotographic developer is disclosed. According to this method, since the hydroxyl group that has not been treated with hexamethyldisilazane or the silane coupling agent is hydrophobized with silicone oil, the degree of hydrophobicity of silica is increased. However, since the silicone oil of this treatment is hardly immobilized on the silica surface, if treated with a large amount of silicone oil to increase the degree of hydrophobicity, the amount of silicone oil that is not immobilized increases and the fluidity of the toner decreases. Cheap. For this reason, when combined with toner containing fine polyester resin particles, uneven development and fog are likely to deteriorate.

  Patent Document 3 discloses surface-coated silica coated with two or more different types of silicone oil, and the amount of silicone oil extracted with chloroform is 5 to 95% by mass of the total silicone oil coated. In addition, there is disclosed a surface-coated silica characterized in that at least one kind of silicone oil is not contained in the extracted silicone oil. Although this method can control the amount of free silicone oil present on the silica surface, the silicone oil has a higher molecular weight than a reaction treatment agent such as dimethyldichlorosilane or hexamethyldisilazane. It is hard to get into. Therefore, hydroxyl groups that have not been hydrophobized are likely to remain on the silica surface, and are susceptible to dew condensation due to changes in the use environment.

Patent Document 4 discloses a silica powder obtained by surface-treating a raw silica powder with polysiloxane and a trimethylsilylating agent, and a ratio of 0.3 to 1.5 trimethylsilyl groups per 1 nm ² of surface area of the raw silica powder. The polysiloxane is A / 20 to A / 5 parts by mass with respect to 100 parts by mass of the raw silica powder (where A is the specific surface area (m ² / g) of the raw silica powder). .)) Is disclosed which is characterized in that it adheres at a rate of. Also disclosed is a method for producing a hydrophobic silica powder, characterized in that the silica powder is treated with polysiloxane and then with a trimethylsilylating agent.

  Patent Document 5 discloses a highly dispersed highly hydrophobic silica powder characterized by having a hydrophobicity of 95% or more, a degree of hydrophobicity of 76% or more, and a distribution density concentrated in a particle size range of 10 to 70 μm. It is disclosed. Also, a highly dispersed hydrophobic silica comprising the steps of primary surface treatment with a silicone oil-based treatment agent, pulverization after the primary surface treatment, and secondary surface treatment with an alkylsilazane-based treatment agent after pulverization A method for producing a powder is disclosed.

  In these methods, the surface treatment with silicone oil is followed by a hydrophobization treatment with a treating agent such as hexamethyldisilazane, so that the silicone oil is easily immobilized on the silica surface, and the hydrophobicity of silica can be increased. . However, when combined with toner particles containing polyester resin fine particles, the degree of hydrophobicity is insufficient to prevent toner aggregation in severe use environments where condensation occurs due to environmental fluctuations.

  As described above, in order to obtain a toner that can cope with a sudden change in the use environment and does not cause an image flow, further contrivance is required for the combination of toner particles and hydrophobic inorganic fine particles.

Japanese Patent Laid-Open No. 08-227171 Japanese Patent Publication No.7-113783 JP 2007-176747 A JP 2002-256170 A JP 2004-168559 A

  Therefore, the present invention has been made in view of the above-described circumstances in the prior art for the purpose of improving the drawbacks.

  That is, an object of the present invention is to provide a toner that does not cause density unevenness even in a sudden change in use environment.

  It is a further object of the present invention to provide a toner that does not cause image flow.

The present invention relates to a toner having toner particles containing a binder resin, a colorant and a release agent, and hydrophobic inorganic fine particles.
The hydrophobic inorganic fine particles are hydrophobic inorganic fine particles that have been surface-treated with a silane compound and / or a silazane compound after the surface treatment with silicone oil (A),
The toner particles are obtained through a step of aggregating at least resin fine particles, colorant fine particles, and release agent fine particles to form an aggregate of fine particles, and an aging step of causing fusion between the fine particles in the aggregate. Toner particles,
The toner particles contain at least a polyester resin as a main component,
In a flow type particle image measuring apparatus having an image processing resolution of 512 × 512 pixels (0.19 μm × 0.19 μm per pixel), the equivalent circle diameter for the number of particles having an equivalent circle diameter of 0.25 μm to less than 39.5 μm. The present invention relates to a toner characterized in that the ratio of the number of particles of 0.25 μm or more and less than 1.98 μm is 1.0 number% or more and 30.0 number% or less.

  According to the present invention, it is possible to provide a toner in which density unevenness does not occur even when the use environment is suddenly changed. Furthermore, according to the present invention, it is possible to provide a toner that does not cause image flow.

  The toner particles used in the present invention are produced by an emulsion aggregation method. There are various merits in the production of toner particles by the emulsion aggregation method, but there is a demerit that some fine particles used as a raw material cannot be combined with the toner particles and exist as free fine particles.

  Since the free fine particles have a smaller particle size than the toner particles, they have a strong adhesion to the photoconductor and are likely to remain on the photoconductor without being transferred to the transfer material. Further, since the particle size is small, it is difficult to scrape with the cleaning blade, and it is easy to slip through the cleaning blade. As a result, it tends to accumulate on a contact charging member such as a charging roller or remain attached to the surface of the photoreceptor.

  In particular, when the binder resin contains a polyester resin as a main component, the fine particles of the polyester resin are included in the free fine particles. The polyester resin is easy to adsorb moisture and has a large surface area in the form of fine particles, so it is greatly affected by moisture. As a result, fine particles accumulated on the contact charging member and fine particles adhering to the surface of the photoreceptor adsorb moisture, lowering the electrical resistance on the surface of the photoreceptor, and disturbing the electrostatic latent image. Problems are likely to occur.

  Furthermore, toner containing free particles of polyester resin stored in a high-temperature and high-humidity environment (such as a warehouse without air conditioning; for example, an environment where the temperature is 30 ° C. or higher and the humidity is 80% or higher). If the cartridge is brought into a room temperature or low temperature environment with air conditioning equipment and used immediately, density unevenness may occur in a uniform image such as a halftone image.

  Although the mechanism of this phenomenon is not clear, it is presumed as follows. By storing the cartridge in a high-temperature and high-humidity environment, the free fine particles of the polyester resin adsorb moisture, and the adsorbed moisture is condensed due to environmental changes (temperature decrease). Condensation of the toner is formed with the condensed moisture as a core, and a toner agglomeration is formed to the extent that it can be loosened if a strong force is applied. Even if the cartridge is brought from a high temperature and high humidity environment to a low temperature environment, the density unevenness does not occur when the cartridge is used after being left for several days.

  As a result of intensive studies by the present inventors for such problems, the toner particles obtained by the emulsion aggregation method were surface-treated with a silicone oil (A) and then with a silane compound and / or a silazane compound. Equivalent to the circle of the toner in a flow type particle image measuring device containing hydrophobic inorganic fine particles and having an image processing resolution of 512 × 512 pixels (0.19 μm × 0.19 μm per pixel) in the particle size distribution of the toner It is important that the ratio of the number of particles with an equivalent circle diameter of 0.25 μm to less than 1.98 μm to the number of particles with a diameter of 0.25 μm to less than 39.5 μm is 1.0 number% to 30.0 number%. I found out.

  Particles having an equivalent circle diameter of 0.25 μm or more and less than 1.98 μm in the toner measured in the present invention represent free fine particles, and the ratio of the number of particles is 1.0 to 30.0% by number. The following (preferably 1.0% or more and 20.0% or less, more preferably 1.0% or more and 10.0% or less) has a large effect on image flow and density unevenness. When there are more than 30.0% by number of particles having an equivalent circle diameter of 0.25 μm or more and less than 1.98 μm, sufficient effects cannot be obtained even when combined with the hydrophobic inorganic fine particles of the present invention, and image flow and density unevenness deteriorate. Sometimes. Particles with an equivalent circle diameter of 0.25 μm or more and less than 1.98 μm are preferably reduced as much as possible, and can be reduced by adjusting toner particle production conditions such as an aggregation step and a classification step when producing toner particles. However, considering production capacity and production cost, it is difficult to make it less than 1.0% by number at present.

  The hydrophobic inorganic fine particles used in the present invention are characterized in that they are surface-treated with a silane compound and / or a silazane compound after the surface treatment with silicone oil (A). Hydrophobic inorganic fine particles treated in this way have a very high degree of hydrophobicity. Therefore, when combined with toner particles obtained by an emulsion aggregation method, including fine polyester resin fine particles, density unevenness, image flow, etc. Very effective in suppressing It is thought that the hydrophobic inorganic fine particles having a very high degree of hydrophobicity adhere to the surface of the free polyester resin fine particles, thereby suppressing moisture adsorption of the polyester resin and preventing condensation due to fluctuations in the use environment.

  When the inorganic fine particles are hydrophobized, the surface of the inorganic fine particles is treated with a silane compound and / or a silazane compound after first treating with the silicone oil so that the silicone oil is fixed on the surface of the inorganic fine particles. The degree of hydrophobicity of can be made higher than ever. What is important here is that hydrophilic inorganic fine particles that have not been hydrophobized are treated with silicone oil.

  By applying silicone oil in a state where there are many hydroxyl groups on the surface of the inorganic fine particles that are not hydrophobized, and by baking the silicone oil and inorganic fine particles at a high temperature, the adhesion between the inorganic fine particles and the silicone oil is increased. It becomes possible to increase the immobilization ratio of silicone oil to inorganic fine particles. This is because when hydrophilic inorganic fine particles are treated at a high temperature, a reaction occurs in which one water molecule is dehydrated from two adjacent hydroxyl groups on the surface of the inorganic fine particles. This is thought to be because the part is immobilized on the surface of the inorganic fine particles.

  Furthermore, by treating with a silane compound and / or silazane compound after the silicone oil treatment, the fine irregularities on the surface of the inorganic fine particles that can not enter the silicone oil are hydrophobized with the silane compound and / or silazane compound. Therefore, it is possible to obtain inorganic fine particles that have been uniformly hydrophobized without unevenness.

  On the other hand, when the hydrophilic inorganic fine particles are first treated with a silane compound and / or a silazane compound and then treated with silicone oil as in Patent Document 2, the hydroxyl group on the surface of the inorganic fine particles becomes a silane compound. And / or most is consumed by reaction with a silazane compound. For this reason, since the silicone oil treatment is performed in a state where the number of hydroxyl groups for fixing the silicone oil is small, it is difficult to increase the fixing rate of the silicone oil. If the treatment is performed at a higher temperature in order to increase the fixing rate of the silicone oil, the silane compound and / or silazane compound on the surface of the previously treated inorganic fine particles may be decomposed, which may reduce the degree of hydrophobicity. is there. In addition, in order to sufficiently increase the degree of hydrophobicity, it is necessary to add a large amount of silicone oil, the amount of silicone oil that is not immobilized increases, the fluidity of the inorganic fine particles decreases, and the surface of the free fine particles is uniform. It becomes difficult to adhere to.

  The hydrophobic inorganic fine particles used in the present invention have high fluidity due to the high immobilization ratio of silicone oil, and even if the particles are small in size, such as free fine particles, the hydrophobic inorganic fine particles are uniform on the surface. Can be attached to. Therefore, even when free fine particles are exposed to a high-temperature and high-humidity environment, moisture can be prevented from being adsorbed, and density unevenness and image flow can be suppressed.

  The degree of hydrophobicity of the hydrophobic inorganic fine particles used in the present invention indicates the concentration of methanol in which the total amount of the hydrophobic inorganic fine particles is suspended in the solution in the wettability test with respect to the methanol / water mixed solvent. In the present invention, those having a methanol concentration of 86% by volume or more are preferably used. The total amount of hydrophobic inorganic fine particles indicates that the higher the concentration of methanol suspended in the solution, the higher the degree of hydrophobicity, and it is possible to suppress free fine particles from adsorbing moisture, resulting in uneven density and image flow. Demonstrate the effect.

  The methanol concentration in which the total amount of the hydrophobic inorganic fine particles of the present invention is suspended in the solution is measured by the following method.

  Add 0.20 g of hydrophobic inorganic fine particles to 50 ml of pure water in a 500 ml beaker. While stirring with a magnetic stirrer, while the hydrophobic inorganic fine particles are floating on the liquid surface, methanol is injected under continuous addition at a dropping rate of 4.0 ml / min. When the total amount of the hydrophobic inorganic fine particles is suspended in the solution and no hydrophobic inorganic fine particles are observed on the liquid surface, the methanol concentration at this time is defined as the degree of hydrophobicity of the hydrophobic inorganic fine particles.

The amount of methanol added is X, and the degree of hydrophobicity (M.W.) is determined according to the following formula.
Hydrophobicity (%) = X / (50 + X) × 100

  The amount of methanol M corresponding to the degree of hydrophobicity is, for example, M = 200.0 ml when the degree of hydrophobicity is 80%, and M = 450.0 ml when the degree of hydrophobicity is 90%. Even if it is small, the difference in the amount of methanol is large.

The hydrophobic inorganic fine particles used in the present invention preferably have a BET specific surface area of 50 m ² / g or more and 300 m ² / g or less. When the BET specific surface area of the hydrophobic inorganic fine particles is within this range, the hydrophobic inorganic fine particles have high fluidity and can be uniformly attached to particles having an equivalent circle diameter of 0.25 μm or more and less than 1.98 μm in the toner particles. This is preferable because it is effective in suppressing density unevenness and image flow.

<Method for measuring BET specific surface area of hydrophobic inorganic fine particles>
The BET specific surface area of the hydrophobic inorganic fine particles is measured according to JIS Z8830 (2001). A specific measurement method is as follows.

  As a measuring device, an “automatic specific surface area / pore distribution measuring device TriStar 3000 (manufactured by Shimadzu Corporation)” which employs a gas adsorption method by a constant volume method as a measuring method is used. Setting of measurement conditions and analysis of measurement data are performed using dedicated software “TriStar3000 Version 4.00” attached to the apparatus, and a vacuum pump, a nitrogen gas pipe, and a helium gas pipe are connected to the apparatus. The value calculated by the BET multipoint method using nitrogen gas as the adsorption gas is defined as the BET specific surface area in the present invention.

  The BET specific surface area is calculated as follows.

First, nitrogen gas is adsorbed to hydrophobic inorganic fine particles, and the equilibrium pressure P (Pa) in the sample cell and the nitrogen adsorption amount Va (mol · g ⁻¹ ) of the toner at that time are measured. The relative pressure Pr, which is a value obtained by dividing the equilibrium pressure P (Pa) in the sample cell by the saturated vapor pressure Po (Pa) of nitrogen, is plotted on the horizontal axis, and the nitrogen adsorption amount Va (mol · g ⁻¹ ) is plotted on the vertical axis. The adsorption isotherm is obtained. Next, a monomolecular layer adsorption amount Vm (mol · g ⁻¹ ), which is an adsorption amount necessary for forming a monomolecular layer on the surface of the toner, is obtained by applying the following BET equation.
Pr / Va (1-Pr) = 1 / (Vm * C) + (C-1) * Pr / (Vm * C)
(Here, C is a BET parameter, which is a variable that varies depending on the measurement sample type, adsorbed gas type, and adsorption temperature.)

  The BET equation is interpreted as a straight line with an inclination of (C-1) / (Vm × C) and an intercept of 1 / (Vm × C), where Pr is X axis and Pr / Va (1-Pr) is Y axis. Yes (this line is called a BET plot).

Straight line slope = (C-1) / (Vm × C)
Straight line intercept = 1 / (Vm × C)

  When the measured value of Pr and the measured value of Pr / Va (1-Pr) are plotted on a graph and a straight line is drawn by the least square method, the slope and intercept value of the straight line can be calculated. Vm and C can be calculated by solving the above slope and intercept simultaneous equations using these values.

Furthermore, the BET specific surface area S (m ² · g ⁻¹ ) of the hydrophobic inorganic fine particles is calculated from the calculated Vm and the molecular occupation cross-sectional area (0.162 nm ² ) of the nitrogen molecule based on the following formula. .
S = Vm × N × 0.162 × 10 ⁻¹⁸
(N is Avogadro's number (mole- ¹ ).)

  The measurement using this apparatus follows the “TriStar 3000 Instruction Manual V4.0” attached to the apparatus, and specifically, the measurement is performed according to the following procedure.

  Thoroughly weigh the tare of a dedicated glass sample cell (stem diameter 3/8 inch, volume about 5 ml) that has been thoroughly cleaned and dried. Then, about 0.3 g of hydrophobic inorganic fine particles are put into this sample cell using a funnel.

  The sample cell containing the hydrophobic inorganic fine particles is set in a “pretreatment device Bacrepep 061 (manufactured by Shimadzu Corporation)” connected with a vacuum pump and a nitrogen gas pipe, and vacuum degassing is continued at 23 ° C. for about 10 hours. To do. In the vacuum degassing, degassing is gradually performed while adjusting the valve so that the hydrophobic inorganic fine particles are not sucked into the vacuum pump. The pressure in the cell gradually decreases with deaeration and finally becomes about 0.4 Pa (about 3 mTorr). After completion of vacuum degassing, nitrogen gas is gradually injected to return the inside of the sample cell to atmospheric pressure, and the sample cell is removed from the pretreatment device. Then, the mass of the sample cell is precisely weighed, and the accurate toner mass is calculated from the difference from the tare. At this time, the sample cell is covered with a rubber stopper during weighing so that the hydrophobic inorganic fine particles in the sample cell are not contaminated by moisture in the atmosphere.

  Next, a dedicated “isothermal jacket” is attached to the stem portion of the sample cell containing the hydrophobic inorganic fine particles. Then, a dedicated filler rod is inserted into the sample cell, and the sample cell is set in the analysis port of the apparatus. The isothermal jacket is a cylindrical member having an inner surface made of a porous material and an outer surface made of an impermeable material capable of sucking liquid nitrogen to a certain level by capillary action.

  Subsequently, the free space of the sample cell including the connection tool is measured. Free space is measured by measuring the volume of the sample cell with helium gas at 23 ° C., and then measuring the volume of the sample cell after cooling the sample cell with liquid nitrogen in the same manner using helium gas. Calculated from the difference in volume. Further, the saturated vapor pressure Po (Pa) of nitrogen is automatically measured separately using a Po tube built in the apparatus.

  Next, after performing vacuum deaeration in the sample cell, the sample cell is cooled with liquid nitrogen while continuing the vacuum deaeration. Thereafter, nitrogen gas is gradually introduced into the sample cell to adsorb nitrogen molecules to the hydrophobic inorganic fine particles. At this time, the adsorption isotherm is obtained by measuring the equilibrium pressure P (Pa) as needed, and the adsorption isotherm is converted into a BET plot. Note that the points of the relative pressure Pr for collecting data are set to a total of 6 points of 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30. A straight line is drawn from the obtained measurement data by the least square method, and Vm is calculated from the slope and intercept of the straight line. Further, using the value of Vm, the BET specific surface area of the hydrophobic inorganic fine particles is calculated as described above.

  The hydrophobic inorganic fine particles used in the present invention are hydrophobic inorganic fine particles that have been surface-treated with a silicone oil (A), surface-treated with a silane compound and / or silazane compound, and further surface-treated with silicone oil (B). Is more preferable.

  After the surface treatment with silicone oil (A), surface treatment with silane compound and / or silazane compound makes the inorganic fine particles hydrophobic, and further with silicone oil (B), the surface treatment with hydrophobic inorganic fine particles Free silicone oil can be applied which is not immobilized.

  By applying a small amount of free silicone oil to the surface of the hydrophobic inorganic fine particles, it is possible to improve the releasability between the toner developed on the photoconductor and the free fine particles and the photoconductor. As a result, the fine particles of the free polyester resin developed on the surface of the photosensitive member together with the toner are improved in transferability and cleaning properties, and hardly remain on the surface of the photosensitive member or the contact transfer member. These effects make it possible to greatly improve the image flow.

  In the present invention, after the surface treatment with the silicone oil (A), the surface treatment with the silane compound and / or the silazane compound makes the hydrophobicity of the hydrophobic inorganic fine particles sufficiently high. Therefore, the treatment with the silicone oil (B) does not need to increase the degree of hydrophobicity of the hydrophobic inorganic fine particles, and provides the minimum amount of free silicone oil necessary for improving the releasability from the photoreceptor. It becomes possible. By minimizing the amount of free silicone oil, the image flow can be greatly improved without lowering the fluidity of the toner or deteriorating the chargeability.

  On the other hand, when the inorganic fine particles are first surface-treated with a silane compound and / or silazane compound and then surface-treated with silicone oil, it is necessary to add a large amount of silicone oil in order to increase the degree of hydrophobicity. There was a tendency for free silicone oil to increase. In order to reduce free silicone oil, it was necessary to reduce the amount of silicone oil, and the degree of hydrophobicity tended to decrease. That is, as in the present invention, it was difficult to provide a small amount of free silicone oil having a high degree of hydrophobicity and a minimum necessary amount.

  In the hydrophobic inorganic fine particles used in the present invention, the treatment amount of the silicone oil (A) is 10 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the inorganic fine particle base material, and the silicone oil (A) is immobilized. The rate is preferably 60% by mass or more (preferably 70% by mass or more, more preferably 80% by mass or more).

  By setting the treatment amount of the silicone oil (A) within this range, the hydrophobicity of the hydrophobic inorganic fine particles is sufficiently high, and since there is no excess silicone oil, the fluidity of the toner is also improved. The effect of suppressing density unevenness and image flow is increased.

  Further, when the immobilization ratio of the silicone oil (A) to the hydrophobic inorganic fine particles is within this range, the hydrophobic degree of the hydrophobic inorganic fine particles becomes sufficiently high, and an excellent effect on density unevenness and image flow can be obtained. .

  In particular, in the present invention, in order to increase the immobilization rate of the inorganic fine particles and the silicone oil (A), it is preferable to perform the treatment in the presence of moisture or water vapor during the treatment with the silicone oil (A). Due to the presence of moisture or water vapor during the treatment, the concentration of hydroxyl groups on the surface of the inorganic fine particles becomes high, so the dehydration reaction from the hydroxyl groups on the surface of the inorganic fine particles is likely to occur, and the number of sites where silicone oil is immobilized increases. Silicone oil is more easily immobilized on the surface of the inorganic fine particles.

  Furthermore, in this invention, it is preferable to process in presence of water vapor | steam also in the case of the surface treatment by a silane compound and / or a silazane compound after processing with a silicone oil (A). Since the silane compound and / or the silazane compound is subjected to a hydrophobization treatment by reacting with the hydroxyl group on the surface of the inorganic fine particles, the treatment can be performed more effectively when the hydroxyl group concentration on the surface of the inorganic fine particles is higher. The inorganic fine particles treated with the silicone oil (A) are placed in the presence of water vapor, thereby increasing the hydroxyl concentration in the fine recesses on the surface of the inorganic fine particles where the silicone oil (A) did not enter, Since the reactivity with the silazane compound can be increased, the degree of hydrophobicity can be increased more efficiently.

  In the hydrophobic inorganic fine particles used in the present invention, the treatment amount of the silicone oil (B) is 1 to 10 parts by mass (preferably 1 to 5 parts by mass) with respect to 100 parts by mass of the inorganic fine particle base. And the immobilization rate of the silicone oil (B) is more preferably 40% by mass or less (preferably 30% by mass or less, more preferably 20% by mass or less).

  When the processing amount of the silicone oil (B) is within this range, free silicone oil can be appropriately imparted without deteriorating the fluidity of the hydrophobic inorganic fine particles.

  Further, by making the immobilization rate of the silicone oil (B) 40% by mass or less, it is possible to obtain the effect of improving the releasability with the photoreceptor without deteriorating the fluidity of the hydrophobic inorganic fine particles, Great effect by suppressing image flow.

  The surface treatment of the hydrophobic inorganic fine particles used in the present invention with a silane compound and / or a silazane compound is performed in an amount of 1 to 50 parts by mass of the silane compound and / or the silazane compound with respect to 100 parts by mass of the inorganic fine particle base. Preferably, the amount is preferably 5 to 40 parts by mass, more preferably 15 to 35 parts by mass). When the silane compound and / or silazane compound is in this range, the degree of hydrophobicity increases, and density unevenness and image flow can be suppressed. Further, since the unreacted silane compound and / or silazane compound does not remain on the surface of the inorganic fine particles, the chargeability of the toner can be kept good.

  The inorganic fine particles of the present invention can be treated with a silane compound and / or a silazane compound by a generally known method. For example, a dry process in which a silane compound and / or a silazane compound vaporized into a cloud-like one obtained by stirring inorganic fine particles is reacted, or an inorganic fine particle is dispersed in a solvent and a silane compound and / or silazane compound is dropped. A wet process is mentioned. Particularly preferable is a dry process from the viewpoint of the uniformity of the process, and it is more preferable to perform the process in the presence of water vapor as described above.

  In the present invention, the immobilization of silicone oil on the surface of the inorganic fine particles means that the silicone oil is detached from the surface of the inorganic fine particles regardless of whether the inorganic fine particles and the silicone oil are chemically reacted or not. It represents the degree of ease. The measuring method of the immobilization rate of silicone oil is shown below.

[Measurement method of silicone oil immobilization rate]
(Extraction of free silicone oil)
1. Place 0.5 g of inorganic fine particles and 40 ml of chloroform in a beaker and stir for 2 hours.
2. Stop stirring and let stand for 12 hours.
3. The sample is filtered and washed 3 times with 40 ml of chloroform.

(Measurement of carbon content)
The sample is burned at a temperature of 1100 ° C. in an oxygen stream, and the amount of generated CO and CO ₂ is measured by IR absorbance, and the amount of carbon in the sample is measured. By comparing the amount of carbon before and after extraction of silicone oil, the immobilization rate of silicone oil is calculated.
1. 2 g of sample is put into a cylindrical mold and pressed.
2. 0.15 g of the pressed sample is precisely weighed, placed on a combustion board, and measured with HORIBA, Ltd. EMA-11.
3.100− (carbon amount before extraction−carbon amount after extraction) / carbon amount before extraction × 100 is defined as the silicone oil immobilization rate.

The hydrophobic inorganic fine particles of the present invention preferably have a BET specific surface area of 10 m ² / g or more and 500 m ² / g or less of the inorganic fine particle base material before the hydrophobic treatment. More preferably 50 m ² / g or more 400 meters ² / g or less, more preferably in not more than 100 m ² / g or more 350m ² / g.

  When the BET specific surface area of the inorganic fine particles is within this range, the particle size of the inorganic fine particles is maintained appropriately, and the hydrophobic inorganic fine particles can be uniformly adhered to the surface of the free fine particles contained in the toner.

  Examples of the inorganic fine particles used in the present invention include wet process silica, dry process silica, oxides such as titanium oxide, alumina, zinc oxide and tin oxide; strontium titanate, barium titanate, calcium titanate, strontium zirconate and zirconate. Double oxides such as calcium acid; carbonate compounds such as calcium carbonate and magnesium carbonate. In order to improve developability and fluidity, it is preferably selected from silica, titanium oxide, alumina, or their suboxides.

In particular, fine powders produced by vapor phase oxidation of silicon halogen compounds, so-called dry silica or fumed silica, are preferred because high chargeability and fluidity can be obtained. For example, a thermal decomposition oxidation reaction of silicon tetrachloride gas in an oxyhydrogen flame is used, and the basic reaction formula is as follows.
SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl

  In this production process, it is also possible to obtain a composite fine powder of silica and another metal oxide by using other metal halogen compounds such as aluminum chloride or titanium chloride together with silicon halogen compounds. As well as those.

  The hydrophobic inorganic fine particles used in the present invention can be applied to both negative toners and positive toners.

  Examples of silicone oils preferably used in the present invention include amino-modified, epoxy-modified, carboxyl-modified, carbinol-modified, methacryl-modified, mercapto-modified, phenol-modified and heterofunctional group-modified reactive silicones; polyether-modified, methylstyryl-modified, Non-reactive silicones such as alkyl-modified, fatty acid-modified, alkoxy-modified and fluorine-modified; straight silicones such as dimethyl silicone, methylphenyl silicone, diphenyl silicone, and methylhydrogen silicone.

  Among these silicone oils, alkyl groups, aryl groups, alkyl groups in which some or all of the hydrogen atoms are substituted with fluorine atoms, and silicone oils having hydrogen as a substituent are preferable. Specific examples include dimethyl silicone oil, methylphenyl silicone oil, methyl hydrogen silicone oil, and fluorine-modified silicone oil.

These silicone oils preferably have a viscosity at 25 ° C. of 5 to 2,000 mm ² / s, more preferably 10 to 1,000 mm ² / s, and even more preferably 30 to 500 mm ² / s. In this range, sufficient hydrophobicity and fluidity can be obtained.

  In the present invention, the silicone oil (A) to be treated first and the silicone oil (B) used in the treatment after the treatment with the silane compound and / or the silazane compound may be the same or different, depending on the purpose. Can be used appropriately.

  Examples of the silane compound used in the present invention include alkoxysilanes such as methoxysilane, ethoxysilane, and propoxysilane, halosilanes such as chlorosilane, bromosilane, and iodosilane, hydrosilanes, alkylsilanes, arylsilanes, vinylsilanes, and acrylics. Examples thereof include silanes, epoxy silanes, silyl compounds, siloxanes, silylureas, silylacetamides, and silane compounds having different substituents of these silane compounds at the same time. By using these silane compounds, fluidity, transferability and charge stabilization can be obtained. A plurality of these silane compounds may be used.

  Specific examples include trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyl. Trichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilyl mercaptan, trimethylsilyl mercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldi Siloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane And dimethylpolysiloxane containing 2 to 12 siloxane units per molecule and containing a hydroxyl group bonded to one Si at each terminal unit. You may use these as a 1 type, or 2 or more types of mixture.

  The silazane compound used in the present invention is a general term for compounds having a Si—N bond in the molecule. Specifically, dimethyldisilazane, trimethyldisilazane, tetramethyldisilazane, pentamethyldisilazane, hexamethyldisilazane, octamethyltrisilazane, hexamethylcyclotrisilazane, tetraethyltetramethylcyclotetrasilazane, tetraphenyldimethyldi Examples include silazane, dipropyltetramethyldisilazane, dibutyltetramethyldisilazane, dihexyltetramethyldisilazane, dioctyltetramethyldisilazane, diphenyltetramethyldisilazane, octamethylcyclotetrasilazane, and the like. Moreover, you may use the organic fluorine-containing silazane compound etc. which substituted these silazane compounds partially with the fluorine etc. Particularly in the present invention, hexamethyldisilazane is preferably used.

  Further, when the hydrophobic inorganic fine particles of the present invention are applied to a positively chargeable toner, the following treatment agent is used.

  Examples of the silicone oil include silicone oil having a nitrogen atom in the side chain. As such a silicone oil, there is a silicone oil having a unit represented by the following formula (1) and / or (2).

［式中、Ｒ₁は水素原子，アルキル基，アリール基またはアルコキシ基を示し、Ｒ₂はアルキレン基またはフェニレン基を示し、Ｒ₃及びＲ₄は水素原子，アルキル基またはアリール基を示し、Ｒ₅は含窒素複素環基を示す。］

[Wherein R ₁ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group, R ₂ represents an alkylene group or a phenylene group, R ₃ and R ₄ represent a hydrogen atom, an alkyl group or an aryl group; ₅ represents a nitrogen-containing heterocyclic group. ]

  Note that the alkyl group, aryl group, alkylene group, and phenylene group may have an organo group having a nitrogen atom, or may have a substituent such as a halogen atom.

  Examples of the silane compound include nitrogen-containing silane compounds.

  Specifically, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane, dibutylaminopropyltrimethoxysilane, monobutylaminopropyltri Methoxysilane, dioctylaminopropyltrimethoxysilane, dibutylaminopropyldimethoxysilane, dibutylaminopropylmonomethoxysilane, dimethylaminophenyltrimethoxysilane, trimethoxysilyl-γ-propylphenylamine, trimethoxysilyl-γ-propylbenzylamine, Trimethoxysilyl-γ-propylpiperidine, trimethoxysilyl-γ-propylmorpholine, trimethoxysilyl-γ- There are propylimidazole and the like. These treatment agents are used singly or as a mixture of two or more kinds or in combination or in multiple treatments.

  The hydrophobic inorganic fine particles of the present invention can be hydrophobized, for example, as follows.

  A known technique is used for the method of hydrophobizing the surface of the raw inorganic fine particles with the silicone oil (A). For example, the raw material of untreated inorganic fine particles is put into the treatment tank and the inside of the treatment tank is stirred. The inorganic fine particles and the silicone oil (A) are mixed while stirring and mixing with a stirring member such as a blade. Mixing with the silicone oil (A) may be carried out directly by using a mixer such as a Henschel mixer, or by spraying the silicone oil (A) onto the raw inorganic fine particles. Alternatively, the silicone oil (A) may be dissolved or dispersed in a suitable solvent, and then mixed with the base inorganic fine particles, and then the solvent may be removed.

  In this treatment, in order to increase the immobilization rate of the silicone oil (A) to the surface of the inorganic fine particles, the treatment is preferably performed while heating, and the treatment temperature is preferably in the range of 150 ° C to 350 ° C, more preferably. Is preferably 200 ° C. or higher and 300 ° C. or lower. By setting to this treatment temperature range, a dehydration reaction from the hydroxyl group on the surface of the inorganic fine particles tends to occur, and the immobilization rate of the silicone oil (A) on the surface of the inorganic fine particles can be easily increased. Furthermore, it is more preferable to perform this treatment in the presence of water vapor in order to increase the immobilization rate of the silicone oil (A).

  In the present invention, the inorganic fine particles treated with the silicone oil (A) are subjected to a surface treatment with at least one treatment agent selected from a silane compound and / or a silazane compound.

  A well-known technique is used for the method of processing with a silane compound and / or a silazane compound. For example, inorganic fine particles treated with silicone oil (A) are put into a treatment tank, and a predetermined amount of silane compound and / or silazane compound is dropped or sprayed while stirring inside the treatment tank with a stirring member such as a stirring blade. And mix thoroughly. At this time, the silane compound and / or the silazane compound can be diluted with a solvent such as alcohol. The inorganic fine particles containing the mixed and dispersed treatment agent are heated to a treatment temperature of 150 ° C. or higher and 350 ° C. or lower (preferably 150 ° C. or higher and 250 ° C. or lower) in a nitrogen atmosphere and refluxed for 0.5 to 5 hours with stirring.

  As a preferable production method, inorganic fine particles treated with silicone oil (A) are put into a treatment tank, and the treatment tank is maintained at a temperature not lower than the boiling point of the silane compound and / or silazane compound to be treated and not higher than the decomposition temperature. Water vapor is blown here so that the hydroxyl groups on the surface of the inorganic fine particles are easily reacted with the silane compound or silazane compound. Furthermore, it is preferable to add a silane compound and / or a silazane compound and treat the surface of the inorganic fine particles by a gas phase reaction. Thereafter, it is also possible to remove surplus materials such as surplus treatment agents as necessary.

  In the present invention, after the treatment with the silicone oil (A), the inorganic fine particles treated with the silane compound and / or the silazane compound are preferably surface treated again with the silicone oil (B). This second silicone oil treatment can be carried out by the same method as the first silicone oil treatment, but it is preferable that the treatment is carried out at a lower temperature because it is preferably not immobilized on the inorganic fine particles. At this time, it should be noted that the treatment is performed at a treatment temperature in a range where the hydrophobic groups introduced to the surface of the inorganic fine particles are not decomposed by the treatment with the silane compound and / or the silazane compound. Preferably, the silicone oil treatment is performed at a treatment temperature of 200 ° C. or less.

  In particular, since the silicone oil (B) is preferably not evenly fixed on the surface of the inorganic fine particles and preferably uniformly adhered, the silicone oil (B) is dissolved or dispersed in a suitable solvent, and the base inorganic A method of preparing by mixing with fine particles and then removing the solvent is preferable.

  The hydrophobic inorganic fine particles of the present invention are preferably used in an addition amount of 0.1 to 5 parts by mass with respect to 100 parts by mass of the toner particles.

  Hereinafter, the emulsion aggregation method, which is a method for producing the toner particles used in the present invention, will be described with specific materials.

  In the emulsion aggregation method, for example, a dispersion of resin fine particles is prepared by stirring various binder resin materials in a medium or by emulsion polymerization, and a dispersion of colorant fine particles, release agent fine particles, and other as required. This is a method for producing toner particles in which toner particles are obtained by heteroaggregating together with a dispersion of components and then fusing.

[Preparation of each dispersion]
<Binder resin>
The dispersion of resin fine particles is obtained by dispersing at least resin fine particles in a dispersant. An example of the resin fine resin is a thermoplastic resin. Specific examples of the binder resin that can be used in the toner of the present invention include the following. Ethylene resins such as polyethylene and polypropylene, styrene resins mainly composed of polystyrene, poly (α-methylstyrene), (meth) acrylic resins mainly composed of polymethyl methacrylate, polyacrylonitrile, polyamide resins , Polycarbonate resins, polyether resins, polyester resins and copolymer resins thereof. In the toner of the present invention, it is important that a polyester resin is a main component from the viewpoint of charging stability and development durability.

  The composition of the polyester resin used in the present invention is as follows.

  Examples of the divalent alcohol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1, 6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, bisphenol represented by the following formula (A) and derivatives thereof; diols represented by the following formula (B); Can be mentioned.

（式中、Ｒはエチレンまたはプロピレン基であり、ｘ，ｙはそれぞれ０以上の整数であり、かつ、ｘ＋ｙ平均値は０乃至１０である。）

ｘ’及びｙ’は、０以上の整数であり、かつ、ｘ＋ｙの平均値は０乃至１０である。）

(In the formula, R is an ethylene or propylene group, x and y are each an integer of 0 or more, and the average value of x + y is 0 to 10.)

x ′ and y ′ are integers of 0 or more, and the average value of x + y is 0 to 10. )

  Divalent acid components include benzene dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and phthalic anhydride, or their anhydrides, lower alkyl esters; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid. Or its anhydride, lower alkyl ester; alkenyl succinic acid or alkyl succinic acid such as n-dodecenyl succinic acid, n-dodecyl succinic acid, or anhydride, lower alkyl ester thereof; fumaric acid, maleic acid, citraconic acid, itaconic acid, etc. Dicarboxylic acids such as unsaturated dicarboxylic acids or anhydrides thereof, lower alkyl esters; and derivatives thereof.

  In the present invention, a carboxylic acid component containing 90 mol% or more of an aromatic carboxylic acid compound and a polyester obtained by condensation polymerization of an alcohol component, and 80 mol% or more of the aromatic carboxylic acid compound is terephthalic acid and / or isophthalic acid. An acid is preferred.

  The polyester resin used in the present invention may have a crosslinked structure. Examples of the monomer that forms a crosslinked structure include trivalent or higher alcohol components and trivalent or higher acid components.

  Examples of the trihydric or higher polyhydric alcohol component include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol. 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxybenzene, etc. Can be mentioned.

  Trivalent or higher polyvalent carboxylic acid components include trimellitic acid, pyromellitic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, tetra (methylene Carboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, empol trimer acid, and anhydrides thereof, lower alkyl esters; tetracarboxylic acid represented by the following formula (C) and the like, and anhydrides thereof And polyvalent carboxylic acids such as lower alkyl esters and derivatives thereof.

（式中Ｘは炭素数３以上の側鎖を１個以上有する炭素数５乃至３０のアルキレン基又はアルケニレン基）

(Wherein X is an alkylene group or alkenylene group having 5 to 30 carbon atoms having one or more side chains having 3 or more carbon atoms)

  These monomers for forming a crosslinked structure may be used alone or in combination of two or more.

  The alcohol component is 40 to 60 mol%, preferably 45 to 55 mol%, and the acid component is 60 to 40 mol%, preferably 55 to 45 mol%.

  The polyester resin is usually obtained by commonly known condensation polymerization.

  Catalysts usable in the production of the polyester resin used in the present invention include alkali metal compounds such as sodium and lithium, alkaline earth metal compounds such as magnesium and calcium, zinc, manganese, antimony, titanium, tin, zirconium, and germanium. Metal compounds such as phosphorous compounds, phosphoric acid compounds, and amine compounds. Specific examples include sodium acetate, sodium carbonate, lithium acetate, lithium carbonate, calcium acetate, calcium stearate, magnesium acetate, acetic acid. Zinc, zinc stearate, zinc naphthenate, zinc chloride, manganese acetate, manganese naphthenate, titanium tetraethoxide, titanium tetrapropoxide, titanium tetraisopropoxide, titanium tetrabutoxide, antimony trioxide, triphenylan Mon, tributylantimony, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin oxide, zirconium tetrabutoxide, zirconium naphthenate, zirconium carbonate, zirconium acetate, zirconium stearate, zirconium octylate, germanium oxide, Examples of the compound include triphenyl phosphite, tris (2,4-di-t-butylphenyl) phosphite, ethyltriphenylphosphonium bromide, triethylamine, and triphenylamine. Among these, a tin-based catalyst and a titanium-based catalyst are preferable from the viewpoint of chargeability, and among them, dibutyltin oxide and titanium tetrabutoxide are preferably used.

  The polyester resin used in the present invention preferably has a weight average molecular weight in the range of 5,000 or more and 30,000 or less, and 7,000 or more and 20,000 or less, as measured by gel permeation chromatography (GPC). More preferably, it is the range. When the weight average molecular weight is in this range, the balance between toner fixing property, offset resistance, and development durability is excellent.

  The acid value of the polyester resin used in the present invention is 2.0 mgKOH / g or more and 25.0 mgKOH / g or less (preferably 3.0 mgKOH / g or more and 20.0 mgKOH / g or less, more preferably 4.0 mgKOH / g or more and 15 or more. 0.0 mgKOH / g or less) is preferable. It is preferable that the acid value be within this range since the stability of the fine particles in the aggregation process is excellent and the hygroscopicity of the toner is kept low, and the toner is less affected by the use environment. The acid value is the number of mg of potassium hydroxide necessary to neutralize the acid contained in 1 g of the sample. The acid value is measured according to JIS K 0070-1992.

  The glass transition temperature of the polyester resin used in the present invention is preferably in the range of 45 ° C. to 80 ° C. (preferably 50 ° C. to 75 ° C., more preferably 55 ° C. to 65 ° C.). When the glass transition temperature is within this range, it is possible to obtain a toner excellent in fixing property and storage property.

  The glass transition temperature (Tg) is measured according to ASTM D3418-82 using, for example, a differential scanning calorimetric analyzer “Q1000” (manufactured by TA Instruments).

  Furthermore, in the present invention, it is preferable to contain a crystalline polyester resin in order to increase the mechanical strength of the toner and to impart development durability. Crystalline polyester is a very hard substance at room temperature even if it has a melting point as low as that of the release agent. By incorporating it in the toner particles, the mechanical strength of the toner particles can be increased, and the toner for long-term use It is preferably used because it is possible to suppress the deterioration.

  The toner particles of the present invention preferably contain 1 to 30 parts by mass of a crystalline polyester resin with respect to 100 parts by mass of the binder resin. When the content of the crystalline polyester resin is within this range, an effect of suppressing the deterioration of the toner can be obtained, and the dispersion state of the colorant and the release agent can be kept good, and the chargeability of the toner can be kept high. I can do it.

  In the present invention, the polyester resin used as the main component of the binder resin represents an amorphous polyester resin unless otherwise specified. Amorphous polyester resin is not a clear endothermic peak but a stepwise endothermic change in thermal analysis using differential scanning calorimetry (DSC). Refers to those that are thermoplasticized at a temperature of

  On the other hand, the crystalline polyester resin refers to a resin having a clear endothermic peak instead of a stepwise endothermic amount change in differential scanning calorimetry (DSC).

  As the crystalline polyester resin used in the present invention, an aliphatic crystalline polyester resin having an appropriate melting point is preferable.

  The crystalline polyester resin is synthesized from an acid (dicarboxylic acid) component and an alcohol (diol) component. In the present invention, “acid-derived constituent component” refers to a constituent portion that was an acid component before the synthesis of the polyester resin, and “alcohol-derived constituent component” is an alcohol component before the synthesis of the polyester resin. Refers to the constituent parts. In the present invention, in the case of a polymer obtained by copolymerizing other components with respect to the crystalline polyester main chain, when the other components are 50% by mass or less, this copolymer is also called crystalline polyester.

  The acid-derived constituent component is preferably an aliphatic dicarboxylic acid, and particularly preferably a linear carboxylic acid. Examples of the linear carboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10- Decanedicarboxylic acid, 1,11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, 1,18-octadecane Dicarboxylic acid, etc., or lower alkyl esters and acid anhydrides thereof. Among these, those having 6 to 10 carbon atoms are preferable from the viewpoint of crystal melting point and chargeability. In order to increase the crystallinity, these linear dicarboxylic acids are preferably used in an amount of 95 mol% or more, more preferably 98 mol% or more of the acid component.

  The other monomer is not particularly limited. For example, a conventionally known divalent or carboxylic acid which is a monomer component described in “Polymer Data Handbook: Basic Edition” (Edited by Polymer Society: Bafukan). There are acids and dihydric alcohols. Specific examples of these monomer components include divalent carboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, and cyclohexanedicarboxylic acid. And dibasic acids such as these, anhydrides thereof, and lower alkyl esters thereof. These may be used individually by 1 type and may use 2 or more types together.

  As the acid-derived constituent component, in addition to the aforementioned aliphatic dicarboxylic acid-derived constituent component, it is preferable that a constituent component such as a dicarboxylic acid-derived constituent component having a sulfonic acid group is included.

  A dicarboxylic acid having a sulfonic acid group is effective in that it can favorably disperse a coloring material such as a pigment. Further, when a resin fine particle dispersion is prepared by emulsifying or suspending the entire resin in water, if a sulfonic acid group is present, it can be emulsified or suspended without using a surfactant as described later. Examples of such a dicarboxylic acid having a sulfone group include, but are not limited to, 2-sulfoterephthalic acid sodium salt, 5-sulfoisophthalic acid sodium salt, and sulfosuccinic acid sodium salt. Moreover, these lower alkyl esters, acid anhydrides, etc. are also mentioned. Among these, 5-sulfoisophthalic acid sodium salt is preferable in terms of cost. The content of the dicarboxylic acid having a sulfonic acid group is preferably 0.1 to 2.0 mol%, and more preferably 0.2 to 1.0 mol%. When the content is more than 2 mol%, the chargeability may be deteriorated. In the present invention, “constituent mol%” refers to a percentage when each constituent component (acid-derived constituent component, alcohol-derived constituent component) in the polyester resin is 1 unit (mol).

  The alcohol component is preferably an aliphatic dialcohol, such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol. 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-dodecanediol, 1,12-undecanediol, 1,13-tridecanediol, 1,14-tetradecanediol 1,18-octadecanediol, 1,20-eicosanediol, etc., among which those having 6 to 10 carbon atoms are preferred from the viewpoint of crystal melting point and chargeability. In order to enhance crystallinity, these linear dialcohols are preferably used in an amount of 95 mol% or more, more preferably 98 mol% or more of the alcohol constituent.

  Examples of other divalent dialcohols include bisphenol A, hydrogenated bisphenol A, ethylene oxide or (and) propylene oxide adducts of bisphenol A, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, diethylene glycol, Examples include propylene glycol, dipropylene glycol, 1,3-butanediol, and neopentyl glycol. These may be used individually by 1 type and may use 2 or more types together.

  If necessary, monovalent acids such as acetic acid and benzoic acid, monovalent alcohols such as cyclohexanol and benzyl alcohol, benzenetricarboxylic acid, and naphthalenetricarboxylic acid for the purpose of adjusting the acid value and hydroxyl value. And trihydric alcohols such as anhydrides thereof, lower alkyl esters thereof, glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol can also be used.

  As the catalyst that can be used in the production of the crystalline polyester resin used in the present invention, the same catalyst as that used in the production of the amorphous polyester resin can be used.

  The melting point of the crystalline polyester resin used in the present invention is preferably 50 ° C. or higher and 120 ° C. or lower (preferably 60 ° C. or higher and 110 ° C. or lower, more preferably 60 ° C. or higher and 100 ° C. or lower). By setting the melting point within this range, the storage stability and chargeability of the toner are improved.

  In the present invention, the melting point of the crystalline polyester resin is measured using a differential scanning calorimeter (DSC) to be described later. When a plurality of melting peaks are shown, the maximum peak is regarded as the melting point.

  The crystalline polyester resin has a weight average molecular weight in the range of 5,000 to 50,000, more preferably 10,000 to 30,000, as measured by GPC. When the weight average molecular weight is within this range, the balance between the durability and chargeability of the toner is maintained at a high level.

  The acid value of the crystalline polyester resin is 3.0 mgKOH / g or more and 25.0 mgKOH / g or less (preferably 6.0 mgKOH / g or more and 20.0 mgKOH / g or less, more preferably 9.0 mgKOH / g or more and 18.0 mgKOH). / G or less). By setting the acid value within this range, it becomes possible to keep the hygroscopicity of the crystalline polyester resin low while ensuring the stability of the aggregated particles in the aggregation process, which can improve density unevenness and image flow. I can do it.

  The crystalline polyester resin used in the present invention is preferably used as fine particles (emulsified particles) dispersed in an aqueous medium. More preferably, the fine particles are formed by applying a shearing force to a solution in which a crystalline polyester resin, an aqueous medium, an amorphous polyester resin, and, if necessary, a colorant are mixed.

  At that time, by heating or dissolving the polyester resin in an organic solvent, the viscosity of the polymer liquid can be lowered to form fine particles. A dispersant can also be used for stabilizing the fine particles and increasing the viscosity of the aqueous medium.

  In the present invention, a copolymer obtained by copolymerizing a crystalline polyester resin with a dicarboxylic acid having a sulfonic acid group is preferable because the amount of the dispersant added can be reduced.

  Examples of the organic solvent include ethyl acetate and toluene, which are appropriately selected according to the crystalline polyester resin.

  The amount of the organic solvent used is preferably in the range of 50 to 5000 parts by mass and more preferably in the range of 120 to 1000 parts by mass with respect to 100 parts by mass of the total amount of the binder resin and the crystalline polyester resin. In addition, a colorant can be mixed before forming the emulsified particles.

  Examples of the emulsifier used when forming the emulsified particles include a homogenizer, a homomixer, a cavitron, a clear mix, a pressure kneader, an extruder, and a media disperser. The size of the emulsified particles (droplets) of the polyester resin is preferably in the range of 0.01 to 1 μm, more preferably in the range of 0.03 to 0.3 μm, in terms of the average particle size (volume average particle size). More preferably, the thickness is 0.03 to 0.4 μm.

  In the present invention, a styrene resin, an acrylic resin (including methacrylic resin), and a styrene-acrylic (including methacrylic resin) copolymer resin can be used in combination with the polyester resin which is the main component of the binder resin. It is. The polymerizable monomer constituting these resins will be described below.

  Examples of styrene monomers include styrene, α-methyl styrene, vinyl naphthalene, 2-methyl styrene, 3-methyl styrene, 4-methyl styrene, 2-ethyl styrene, 3-ethyl styrene, 4-ethyl styrene, and the like. Examples include alkyl-substituted styrene having an alkyl chain, halogen-substituted styrene such as 2-chlorostyrene, 3-chlorostyrene, and 4-chlorostyrene, and fluorine-substituted styrene such as 4-fluorostyrene and 2,5-difluorostyrene. Styrene is preferred as the styrene monomer.

  Examples of acrylic acid ester monomers include n-methyl acrylate, n-ethyl acrylate, n-propyl acrylate, n-butyl acrylate, n-pentyl acrylate, n-hexyl acrylate, and n-acrylate. Heptyl, n-octyl acrylate, n-decyl acrylate, n-dodecyl acrylate, n-lauryl acrylate, n-tetradecyl acrylate, n-hexadecyl acrylate, n-octadecyl acrylate, isopropyl acrylate, acrylic acid Isobutyl, t-butyl acrylate, isopentyl acrylate, amyl acrylate, neopentyl acrylate, isohexyl acrylate, isoheptyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, biphenyl acrylate, diacrylate Enylethyl, tert-butylphenyl acrylate, terphenyl acrylate, cyclohexyl acrylate, tert-butyl cyclohexyl acrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, methoxyethyl acrylate, 2-hydroxyethyl acrylate, acrylic acid β-carboxyethyl, acrylonitrile, acrylamide and the like. Moreover, the methacrylic acid type monomer which replaced the acrylic of the said acrylic acid type monomer with methacryl is illustrated. As the acrylate monomer, n-butyl acrylate is preferable.

  The ethylenically unsaturated acid monomer is an ethylenically unsaturated monomer containing an acidic group such as a carboxyl group, a sulfonic acid group, or an acid anhydride.

  The binder resin used in the toner of the present invention can use a chain transfer agent during the polymerization. Although there is no restriction | limiting in particular as a chain transfer agent, The compound which has a thiol component can be used. Specifically, alkyl mercaptans such as hexyl mercaptan, heptyl mercaptan, octyl mercaptan, nonyl mercaptan, decyl mercaptan, and dodecyl mercaptan are preferred, and in particular, the molecular weight distribution is narrow, so that the storage stability of the toner at high temperature is improved. preferable.

  A cross-linking agent may be added to the binder resin in the present invention as necessary. Specific examples of such cross-linking agents include aromatic polyvinyl compounds such as divinylbenzene and divinylnaphthalene; divinyl phthalate, divinyl isophthalate, divinyl terephthalate, divinyl homophthalate, divinyl trimesate / trivinyl, naphthalene dicarboxylate Polyvinyl esters of aromatic polyvalent carboxylic acids such as divinyl acid and diphenyl biphenyl carboxylate; Divinyl esters of nitrogen-containing aromatic compounds such as divinyl pyridine dicarboxylate; Vinyl pyromutate, vinyl furan carboxylate, pyrrole-2- Vinyl esters of unsaturated heterocyclic compounds such as vinyl carboxylate and vinyl thiophenecarboxylate; butanediol methacrylate, hexanediol acrylate, octanediol methacrylate, decanediol acrylate Acrylic acid esters or methacrylic acid esters of linear polyhydric alcohols such as dodecanediol methacrylate; Branches such as neopentyl glycol dimethacrylate and 2-hydroxy-1,3-diacryloxypropane; substituted polyhydric alcohols Acrylic acid esters or methacrylic acid esters; ethylene glycol acrylates or ethylene glycol methacrylates such as polyethylene glycol diacrylate and polypropylene polyethylene glycol diacrylate; divinyl succinate, divinyl fumarate, vinyl / divinyl maleate, divinyl diglycolate , Vinyl itaconate / divinyl, divinyl acetone dicarboxylate, divinyl glutarate, divinyl 3,3′-thiodipropionate, trans-aconitic acid dibi Le / trivinyl, divinyl adipate, pimelic acid divinyl, divinyl suberate, azelate, divinyl sebacate, divinyl dodecanedioate divinyl, the polyvinyl esters of polycarboxylic acids such as oxalic acid divinyl and the like.

  In the present invention, these crosslinking agents may be used alone or in combination of two or more. Among the above crosslinking agents, the crosslinking agent in the present invention includes acrylic acid esters or methacrylic acid of linear polyhydric alcohols such as butanediol methacrylate, hexanediol acrylate, octanediol methacrylate, decanediol acrylate, and dodecanediol methacrylate. Esters; Branched and substituted acrylic esters or methacrylates of neopentyl glycol dimethacrylate, 2-hydroxy-1,3-diacryloxypropane, etc .; polyethylene glycol diacrylate, polypropylene polyethylene It is preferable to use ethylene glycol acrylates such as glycol diacrylate or ethylene glycol methacrylates.

  The content of the cross-linking agent is preferably in the range of 0.05 to 5% by mass, more preferably in the range of 0.1 to 1.0% by mass, based on the total amount of polymerizable monomers.

  Among the binder resins used in the toner of the present invention, those that can be produced by radical polymerization of a polymerizable monomer can be polymerized using a radical polymerization initiator.

  There is no restriction | limiting in particular as an initiator for radical polymerization used here. Specifically, hydrogen peroxide, acetyl peroxide, cumyl peroxide, tert-butyl peroxide, propionyl peroxide, benzoyl peroxide, chlorobenzoyl peroxide, dichlorobenzoyl peroxide, bromomethylbenzoyl peroxide, lauroyl peroxide Ammonium persulfate, sodium persulfate, potassium persulfate, diisopropyl peroxycarbonate, tetralin hydroperoxide, 1-phenyl-2-methylpropyl-1-hydroperoxide, tert-butyl hydroperoxide pertriphenyl acetate, tert-butyl formate, Peroxides such as tert-butyl peracetate, tert-butyl perbenzoate, tert-butyl perphenylacetate, tert-butyl permethoxyacetate, tert-butyl perN- (3-toluyl) carbamate, 2,2 '-Azobisp Bread, 2,2′-dichloro-2,2′-azobispropane, 1,1′-azo (methylethyl) diacetate, 2,2′-azobis (2-amidinopropane) hydrochloride, 2,2 ′ -Azobis (2-amidinopropane) nitrate, 2,2'-azobisisobutane, 2,2'-azobisisobutyramide, 2,2'-azobisisobutyronitrile, 2,2'-azobis-2- Methyl methylpropionate, 2,2′-dichloro-2,2′-azobisbutane, 2,2′-azobis-2-methylbutyronitrile, dimethyl 2,2′-azobisisobutyrate, 1,1′-azobis (1 -Sodium methylbutyronitrile-3-sulfonate), 2- (4-methylphenylazo) -2-methylmalonodinitrile, 4,4'-azobis-4-cyanovaleric acid, 3,5-dihy Roxymethylphenylazo-2-methylmalonodinitrile, 2- (4-bromophenylazo) -2-allylmalonodinitrile, 2,2′-azobis-2-methylvaleronitrile, 4,4′-azobis-4 -Dimethyl cyanovalerate, 2,2'-azobis-2,4-dimethylvaleronitrile, 1,1'-azobiscyclohexanenitrile, 2,2'-azobis-2-propylbutyronitrile, 1,1'- Azobis-1-chlorophenylethane, 1,1′-azobis-1-cyclohexanecarbonitrile, 1,1′-azobis-1-cycloheptanenitrile, 1,1′-azobis-1-phenylethane, 1,1 ′ -Azobiscumene, 4-nitrophenylazobenzyl cyanoacetate ethyl, phenylazodiphenylmethane, phenylazotriphenylmeth Tan, 4-nitrophenylazotriphenylmethane, 1,1′-azobis-1,2-diphenylethane, poly (bisphenol A-4,4′-azobis-4-cyanopentanoate), poly (tetraethylene glycol) -2,2'-azobisisobutyrate) and the like, 1,4-bis (pentaethylene) -2-tetrazene, 1,4-dimethoxycarbonyl-1,4-diphenyl-2-tetrazene and the like Can be mentioned.

  The number average particle diameter of the resin fine particles used in the present invention is usually 1 μm or less, preferably 0.01 to 1 μm. When the number average particle diameter is in the above range, uneven distribution among the toner particles is reduced, dispersion in the toner particles is improved, and variations in performance and reliability are reduced.

<Colorant>
The toner of the present invention contains a colorant as an essential component in order to impart coloring power. As the colorant preferably used in the present invention, any known colorant can be used, and examples thereof include the following organic pigments, organic dyes, and inorganic pigments.

  Examples of organic pigments or organic dyes as cyan colorants include copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, and basic dye lake compounds.

  Examples of the organic pigment or organic dye as the magenta colorant include the following. Condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, perylene compounds.

  Examples of the organic pigment or organic dye as the yellow colorant include compounds represented by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds.

  Examples of the black colorant include carbon black and those prepared by using the above yellow colorant / magenta colorant / cyan colorant to black.

  These colorants can be used alone or in combination and further in the form of a solid solution. The colorant used in the toner of the present invention is selected from the viewpoints of hue angle, saturation, brightness, light resistance, OHP transparency, and dispersibility in the toner.

  The colorant is preferably used by adding 1 part by mass or more and 20 parts by mass or less to 100 parts by mass of the polymerizable monomer or binder resin.

  In the toner production method of the present invention, a dispersion of colorant particles is prepared by dispersing a colorant in an aqueous medium together with a dispersant such as a surfactant by a mechanical impact or the like. The toner particles can be obtained by agglomerating together with the toner particles and granulating the toner particles.

  Specific examples of the colorant dispersion by mechanical impact or the like include, for example, a rotary shear type homogenizer, a ball type mill, a sand mill, an attritor or other media type disperser, a high pressure opposed collision type disperser, etc. A dispersion can be prepared. In addition, these colorants can be dispersed in an aqueous medium by a homogenizer using a polar surfactant.

  The number average particle diameter of the colorant particles in the dispersion is preferably 0.50 μm or less, and more preferably 0.20 μm or less. By setting the number average particle size to 0.50 μm or less, coloring power, color reproducibility, and OHP permeability are improved.

<Release agent>
The toner of the present invention contains a release agent as an essential component. The content of the release agent is preferably 2.0 parts by mass or more and 25.0 parts by mass or less with respect to 100 parts by mass of the binder resin. When the content of the release agent is within this range, the effect of releasability at the time of fixing can be sufficiently exerted, the release agent is less likely to be unevenly distributed on the toner particle surface, and the chargeability of the toner can be improved.

  Further, the release agent preferably has a maximum endothermic peak temperature in the range of 60 ° C. or more and 120 ° C. or less in the DSC curve at the time of temperature rise measured by a differential scanning calorimetry (DSC) apparatus, more preferably. Is 62 ° C. or higher and 110 ° C. or lower, more preferably 65 ° C. or higher and 90 ° C. or lower. When the maximum endothermic peak temperature is within this range, the storage stability and fog of the toner are excellent, and the low-temperature fixability is also good.

  Specific examples of the release agent used in the present invention include the following. Low molecular weight polyolefins such as polyethylene, polypropylene and polybutene; silicones having a softening point upon heating; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide and stearic acid amide; carnauba wax, rice wax, can Plant waxes such as delilla wax, tree wax, jojoba oil; animal waxes such as beeswax; mineral and petroleum waxes such as montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, Fischer-Tropsch wax; fatty acid ester, montan Ester waxes such as acid esters and carboxylic acid esters. In this invention, these mold release agents may be used individually by 1 type, and may use 2 or more types together.

  The number average particle size in the dispersion of the release agent fine particles is preferably 2.0 μm or less, and more preferably 1.0 μm or less.

  The combination of the fine particles of the colorant, the fine particles of the binder resin, and the fine particles of the release agent is not particularly limited and may be appropriately selected depending on the purpose.

<Charge control agent>
If necessary, a charge control agent may be added to the toner of the present invention.

  Known charge control agents can be used, but azo metal complex compounds, metal complex compounds of salicylic acid, and resin type charge control agents containing polar groups can be used. The toner of the present invention may be either a magnetic toner containing a magnetic material or a non-magnetic toner containing no magnetic material.

<Other internal additives>
In the toner of the present invention, other internal additives may be added to the inside of the toner as necessary. The internal additive is generally used for the purpose of controlling the viscoelasticity of the fixed image. Specific examples of the internal additive include inorganic fine particles such as silica and titania, organic fine particles such as polymethyl methacrylate, and the like, and may be surface-treated for the purpose of improving dispersibility. They may be used alone or in combination of two or more internal additives.

<Surfactant>
Examples of the dispersant contained in the resin fine particle dispersion, the colorant fine particle dispersion, and the release agent fine particle dispersion include an aqueous medium containing a polar surfactant. Examples of the aqueous medium include water such as distilled water or ion-exchanged water; alcohols. These may be used alone or in combination of two or more. The content of the polar surfactant in the dispersant having the polarity cannot be generally defined and can be appropriately selected according to the purpose.

  Examples of the polar surfactant include anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap; cationic surfactants such as amine salt type and quaternary ammonium salt type. Specific examples of the anionic surfactant include sodium dodecylbenzenesulfonate, sodium dodecylsulfate, sodium alkylnaphthalenesulfonate, and sodium dialkylsulfosuccinate. Specific examples of the cationic surfactant include alkylbenzene dimethyl ammonium chloride, alkyl trimethyl ammonium chloride, and distearyl ammonium chloride. These may be used alone or in combination of two or more.

  In the present invention, these polar surfactants and nonpolar surfactants can be used in combination. Examples of the nonpolar surfactant include nonionic surfactants such as polyethylene glycol, alkylphenol ethylene oxide adducts, and polyhydric alcohols.

  The content of the resin particles in the dispersion of resin fine particles is usually 5.0 to 60.0% by mass, and preferably 10.0 to 40.0% by mass. Further, the content of the resin particles in the dispersion of aggregated particles when the aggregated particles are formed may be 50.0% by mass or less, and is 2.0 to 40.0% by mass. preferable.

  The content of the colorant fine particles in the colorant fine particle dispersion is 1.0 to 10.0% by mass in the aggregated particle dispersion when the aggregated particles are formed, and 2.0 to 6 0.0 mass% is preferable.

  The content of the release agent fine particles in the dispersion of the release agent fine particles is 0.50 to 20.0% by mass in the dispersion of the aggregated particles when the aggregated particles are formed. 0 to 10.0% by mass is preferable.

(Aggregation process)
<Flocculant>
In the production of the toner of the present invention, agglomeration is caused by a pH change or the like in the agglomeration step, and agglomerated particles containing a binder resin, a colorant, and a release agent can be prepared. At the same time, an aggregating agent may be added to stably and rapidly aggregate the particles, or to obtain aggregated particles having a narrower particle size distribution.

  As the flocculant, a compound having a monovalent or higher charge is preferable. Specific examples of the compound include water-soluble surfactants such as the above-mentioned ionic surfactants and nonionic surfactants, hydrochloric acid, sulfuric acid, Acids such as nitric acid, acetic acid, oxalic acid, magnesium chloride, sodium chloride, aluminum sulfate, calcium sulfate, ammonium sulfate, aluminum nitrate, silver nitrate, copper sulfate, sodium carbonate and other inorganic acid metal salts, sodium acetate, potassium formate, oxalic acid Aliphatic acids such as sodium, sodium phthalate and potassium salicylate, metal salts of aromatic acids, metal salts of phenols such as sodium phenolate, metal salts of amino acids, triethanolamine hydrochloride and aniline hydrochloride And inorganic acid salts of aromatic amines.

  In consideration of the stability of the aggregated particles, the stability of the coagulant with respect to heat and time, and the removal during washing, a metal salt of an inorganic acid is preferable as the coagulant in terms of performance and use. Specific examples include metal salts of inorganic acids such as magnesium chloride, sodium chloride, aluminum sulfate, calcium sulfate, ammonium sulfate, aluminum nitrate, silver nitrate, copper sulfate, and sodium carbonate.

  The amount of these flocculants to be added varies depending on the valence of the charge, but they are all small and are 3.0% by mass or less for monovalent, 1.0% by mass or less for divalent, trivalent. In this case, it is 0.50% by mass or less. Since the amount of the flocculant is preferably small, it is preferable to use a compound having a large valence.

  The addition and mixing of the flocculant is preferably performed at a temperature below the glass transition point of the resin contained in the mixed solution. When the mixing is performed under this temperature condition, aggregation proceeds in a stable state. The mixing can be performed using, for example, a known mixing apparatus, homogenizer, or mixer.

  The particle size of the agglomerated particles formed here is usually controlled to be about the same as the particle size of the toner to be obtained. Control of the particle size of the aggregated particles can be easily performed, for example, by appropriately changing the temperature and the stirring and mixing conditions.

  Through the above-described aggregated particle forming step, aggregated particles having substantially the same particle size as that of the toner are formed, and an aggregated particle dispersion liquid in which the aggregated particles are dispersed is prepared.

(Aging process)
The aging step is a step in which the aggregated particles are heated and fused. Before entering the aging step, the pH adjuster, the polar surfactant, or the nonpolar surfactant can be appropriately added to prevent fusion between the aggregated particles.

  The heating temperature may be at least the glass transition temperature of the binder resin contained in the aggregated particles and less than the decomposition temperature. Therefore, the heating temperature differs depending on the type of resin fine particles and cannot be defined generally, but generally the glass transition temperature of the binder resin contained in the aggregated particles or the adhered particles is 140 ° C. or lower. It is. In addition, heating can be performed using a publicly known heating device / apparatus.

  As the fusion time, a short time is sufficient if the heating temperature is high, and a long time is required if the heating temperature is low. That is, the fusion time depends on the temperature of heating and cannot be defined in general, but is generally 30 minutes to 10 hours. The toner particles obtained after completion of the fusing process are washed and dried under appropriate conditions.

  In the present invention, the ratio of the number of particles with an equivalent circle diameter of 0.25 μm or more and less than 1.98 μm to the number of particles with an equivalent circle diameter of 0.25 μm or more and less than 39.5 μm is 1.0% by number or more and 30.0%. It is also possible to perform a classification operation as necessary so as to be less than or equal to%.

  Classifiers include, for example, a class seal, a micron classifier, a speck classifier (manufactured by Seishin Enterprise); a turbo classifier (manufactured by Nisshin Engineering); a micron separator, a turboplex (ATP), a TSP separator (manufactured by Hosokawa Micron) ); Elbow Jet (manufactured by Nippon Steel & Mining Co., Ltd.), Dispersion Separator (manufactured by Nippon Pneumatic Industrial Co., Ltd.);

(External addition process)
The toner of the present invention is obtained by adding and mixing the hydrophobic inorganic fine particles to the toner particles. A known manufacturing apparatus can be used for the addition and mixing of the toner particles and the hydrophobic inorganic fine particles. For example, the following manufacturing apparatuses can be used depending on the situation.

  For example, as a mixer, Henschel mixer (Mitsui Mining Co., Ltd.); Super mixer (Kawata Co., Ltd.); Ribocorn (Okawara Seisakusho Co., Ltd.); Nauter mixer, Turbulizer, Cyclomix (Hosokawa Micron Co., Ltd.); Spiral pin mixer (Manufactured by Taiheiyo Kiko Co., Ltd.);

  Examples of sieving devices used to screen coarse particles include Ultrasonic (manufactured by Sakae Sangyo Co., Ltd.); Resonator Sheave, Gyroshifter (Tokuju Kosakusha Co., Ltd.); Examples include a turbo screener (manufactured by Turbo Industry Co., Ltd.), a micro shifter (manufactured by Kanno Sangyo Co., Ltd.), and a circular vibrating sieve.

  In addition to the hydrophobic inorganic fine particles, a fluidity improver may be added to the toner of the present invention as necessary. The fluidity improver can be added to the toner particles to increase the fluidity before and after the addition. Examples of such fluidity improvers include the following. Fluorine resin powders such as fine powdery vinylidene fluoride and fine powder of polytetrafluoroethylene; finely powdered titanium oxide, finely powdered alumina, and finely treated surface treated with a silane compound, titanium coupling agent, and silicone oil Powders; oxides such as zinc oxide and tin oxide; double oxides such as strontium titanate, barium titanate, calcium titanate, strontium zirconate and calcium zirconate; carbonate compounds such as calcium carbonate and magnesium carbonate.

  The toner of the present invention can be used as a one-component developer or a two-component developer in combination with a carrier. As the carrier for use in the two-component developer, all conventionally known carriers can be used. Specifically, surface oxidized or unoxidized iron, nickel, cobalt, manganese, chromium, rare earth, etc. Particles with an average particle size of 20 to 300 μm, such as metals and their alloys or oxides, are preferably used.

  Further, those obtained by attaching or coating a resin such as a styrene resin, an acrylic resin, a silicone resin, a fluorine resin, or a polyester resin on the surface of the carrier particles are preferably used.

  The toner of the present invention has a weight average particle diameter (D4) of 3.0 μm or more and 12.0 μm or less (preferably 4.0 μm or more and 10.0 μm or less, more preferably 4.0 μm or more and 8.0 μm or less). preferable. The weight average particle diameter (D4) of the toner is calculated as follows.

  As a measuring device, a precise particle size distribution measuring device “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) using a pore electrical resistance method equipped with a 100 μm aperture tube is used. For setting the measurement conditions and analyzing the measurement data, the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) is used. The measurement is performed with 25,000 effective measurement channels.

  As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

  Prior to measurement and analysis, the dedicated software is set as follows.

  On the “Change Standard Measurement Method (SOM)” screen of the dedicated software, set the total count in the control mode to 50,000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter Set the value obtained using By pressing the “Threshold / Noise Level Measurement Button”, the threshold and noise level are automatically set. In addition, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the “aperture tube flush after measurement” is checked.

  In the “Pulse to particle size conversion setting” screen of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.

The specific measurement method is as follows.
(1) About 200 ml of the electrolytic solution is placed in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rpm. Then, the dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the dedicated software.
(2) About 30 ml of the electrolytic aqueous solution is put into a glass 100 ml flat bottom beaker. In this, "Contaminone N" (nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of neutral detergent for pH7 precision measuring instrument cleaning, made by organic builder, manufactured by Wako Pure Chemical Industries, Ltd. About 0.3 ml of a diluted solution obtained by diluting 3) with ion-exchanged water is added.
(3) Two oscillators with an oscillation frequency of 50 kHz are incorporated with the phase shifted by 180 degrees, and an ultrasonic disperser “Ultrasonic Dissipation System Tetora 150” (manufactured by Nikkaki Bios Co., Ltd.) having an electrical output of 120 W is prepared. About 3.3 l of ion-exchanged water is placed in the water tank of the ultrasonic disperser, and about 2 ml of Contaminone N is added to the water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.
(5) In a state where the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.
(6) To the round bottom beaker of (1) installed in the sample stand, the electrolyte solution of (5) in which the toner is dispersed is dropped using a pipette, and the measurement concentration is adjusted to about 5%. . Then, measurement is performed until the number of measured particles reaches 50,000.
(7) The measurement data is analyzed with the dedicated software attached to the apparatus, and the weight average particle diameter (D4) is calculated. The “average diameter” on the “analysis / volume statistics (arithmetic average)” screen when the graph / volume% is set by the dedicated software is the weight average particle diameter (D4).

  Hereinafter, various measurement methods for the toner of the present invention will be described.

<Ratio of the number of particles having a circle equivalent diameter of 0.25 μm or more and less than 1.98 μm>
With respect to the number of particles having an equivalent circle diameter of 0.25 μm or more and less than 39.5 μm in the flow type particle image measuring apparatus of the toner of the present invention having an image processing resolution of 512 × 512 pixels (0.19 μm × 0.19 μm per pixel), The ratio of the number of particles having an equivalent circle diameter of 0.25 μm or more and less than 1.98 μm was measured by a flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) under the measurement and analysis conditions during calibration work.

  The measurement principle of the flow-type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) is to capture flowing particles as a still image and perform image analysis. The sample added to the sample chamber is fed into the flat sheath flow cell by a sample suction syringe. The sample fed into the flat sheath flow is sandwiched between sheath liquids to form a flat flow. The sample passing through the flat sheath flow cell is irradiated with stroboscopic light with a nucleus for 1/60 second, and the flowing particles can be photographed as a still image. Further, since the flow is flat, the image is taken in a focused state. The particle image is captured by a CCD camera, and the captured image is subjected to image processing at an image processing resolution of 512 × 512 (0.19 μm × 0.19 μm per pixel), and the contour of each particle image is extracted, The projected area S, the peripheral length L, and the like are measured.

Next, the equivalent circle diameter and the circularity are obtained using the area S and the peripheral length L. The equivalent circle diameter is the diameter of a circle having the same area as the projected area of the particle image, and the circularity C is a value obtained by dividing the circumference of the circle obtained from the equivalent circle diameter by the circumference of the projected particle image. And is calculated by the following formula.
Circularity C = 2 × (π × S) 1/2 / L

  When the particle image is circular, the degree of circularity is 1, and the degree of unevenness on the outer periphery of the particle image increases, and the degree of circularity decreases. After calculating the circularity of each particle, the arithmetic average value of the obtained circularity is calculated, and the value is defined as the average circularity.

  A specific measurement method is as follows. First, about 20 ml of ion-exchanged water from which impure solids are removed in advance is put in a glass container. In this, "Contaminone N" (nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of neutral detergent for pH7 precision measuring instrument cleaning, made by organic builder, manufactured by Wako Pure Chemical Industries, Ltd. About 0.2 ml of a diluted solution obtained by diluting the solution with ion exchange water about 3 times by mass. Further, about 0.02 g of a measurement sample is added, and dispersion treatment is performed for 2 minutes using an ultrasonic disperser to obtain a dispersion for measurement. In that case, it cools suitably so that the temperature of a dispersion liquid may become 10 to 40 degreeC. As the ultrasonic disperser, a desktop type ultrasonic cleaner disperser (for example, “VS-150” (manufactured by VervoCrea)) having an oscillation frequency of 50 kHz and an electric output of 150 W is used. Ion exchange water is added, and about 2 ml of the above-mentioned Contaminone N is added to this water tank.

  For the measurement, the above-mentioned flow type particle image analyzer equipped with “LUCPLFLN” (magnification 20 ×, numerical aperture 0.40) as an objective lens is used, and particle sheath “PSE-900A” (manufactured by Sysmex Corporation) is used as the sheath liquid. It was used. The dispersion prepared in accordance with the above procedure is introduced into the flow type particle image analyzer, and 2000 toner particles are measured in the HPF measurement mode and in the total count mode. Then, the binarization threshold at the time of particle analysis was set to 85%, the analysis particle diameter was limited to a circle equivalent diameter of 1.977 μm or more and less than 39.54 μm, and the average circularity of the toner particles was determined.

  In measurement, automatic focus adjustment is performed using standard latex particles (for example, “RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5100A” manufactured by Duke Scientific) diluted with ion-exchanged water before starting the measurement. Thereafter, it is preferable to perform focus adjustment every two hours from the start of measurement.

  In the examples of the present application, a flow-type particle image analyzer that has been issued a calibration certificate issued by Sysmex Corporation, which has been calibrated by Sysmex Corporation, was used. The measurement was performed under the measurement and analysis conditions when the calibration certificate was received, except that the analysis particle diameter was limited to a circle equivalent diameter of 1.977 μm or more and less than 39.54 μm.

  After the measurement, the ratio of the number average particle diameter of the toner less than 2.0 μm was obtained by a calculation process for cutting data having an equivalent circle diameter of less than 2.0 μm.

<Measurement of Maximum Endothermic Peak Temperature in DSC Endothermic Curve at Temperature Increase Measured with DSC Apparatus for Release Agent and Crystalline Polyester Resin>
The measurement of the maximum endothermic peak temperature in the DSC endothermic curve at the time of temperature rise measured by the release agent and the crystalline polyester resin DSC apparatus is, for example, DSC-7 manufactured by PerkinElmer or DSC-2920 manufactured by TA Instruments Japan. Is available. In the present invention, a DSC-2920 manufactured by TA Instruments Japan was used, and the operation was performed according to the operation manual of the apparatus. Specifically, an aluminum pan was used as a measurement sample, and an empty pan was set as a control. The temperature was increased from 20 ° C. with an amplitude of ± 1.5 ° C. and a period of 1 / min. The temperature was raised to 180 ° C. in min, and the maximum endothermic peak temperatures of the release agent and the crystalline polyester resin were obtained from the obtained DSC curve at the time of temperature rise.

  Hereinafter, the present invention will be specifically described with reference to production examples and examples, but this does not limit the present invention in any way.

(Production example 1 of hydrophobic inorganic fine particles)
Untreated dry silica (average primary particle size = 12 nm, BET specific surface area 200 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 250 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas and the reactor was sealed, and 15 parts by mass of dimethyl silicone oil (viscosity = 50 mm ² / s) and water vapor were sprayed as 100 parts by mass of the silica base material as silicone oil (A). And stirring was continued for 30 minutes. Then, it heated up to 300 degreeC, stirring, and also stirred for 2 hours, and the first silicone oil process was complete | finished.

  Thereafter, the temperature of the reactor was lowered to 250 ° C., 30 parts by mass of hexamethyldisilazane was sprayed into the interior together with water vapor with respect to 100 parts by mass of the silica raw material, and the treatment was performed in a fluidized state while stirring. This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane and by-products from the hydrophobic silica. The immobilization rate of the first treated silicone oil (A) was 97% by mass.

Further, the temperature of the reactor was lowered to 150 ° C. while stirring the reaction vessel, and 3 parts by mass of dimethyl silicone oil (viscosity = 50 mm ² / s) was added as silicone oil (B) to 100 parts by mass of the silica raw material. Then, a solution dissolved in 10 parts by mass of toluene as an organic solvent was sprayed and stirred for 2 hours, and then the treatment was completed. Thereafter, the autoclave was depressurized and washed with a nitrogen gas stream to remove toluene from the hydrophobic silica to obtain hydrophobic inorganic fine particles a used in the present invention.

The immobilization rate of the silicone oil (B) of the hydrophobic inorganic fine particles a was 2% by mass. In the measurement of the degree of hydrophobicity, even when the methanol concentration is 90% by volume, the whole amount of the hydrophobic inorganic fine particles is not suspended in the solution, and a part of the hydrophobic inorganic fine particles remain floating on the liquid surface. there were. The hydrophobic inorganic fine particles a had a BET specific surface area of 110 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles a.

(Production Example 2 of hydrophobic inorganic fine particles)
Untreated dry silica (average primary particle size = 12 nm, BET specific surface area 200 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 250 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas and the reactor was sealed, and 15 parts by mass of dimethyl silicone oil (viscosity = 50 mm ² / s) and water vapor were sprayed as 100 parts by mass of the silica base material as silicone oil (A). The stirring was continued for 2 hours, and the first silicone oil treatment was completed.

  Thereafter, 30 parts by mass of hexamethyldisilazane was sprayed into the interior together with water vapor with respect to 100 parts by mass of the silica raw material, and the mixture was processed in a fluidized state while stirring. This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane and by-products from the hydrophobic silica. The immobilization rate of the first treated silicone oil (A) was 84% by mass.

Further, 5 parts by mass of dimethyl silicone oil (viscosity = 50 mm ² / s) as a silicone oil (B) was sprayed on 100 parts by mass of the silica base while stirring the reaction vessel, and the mixture was stirred for 2 hours. When finished, the hydrophobic inorganic fine particles b used in the present invention were obtained.

The immobilization rate of the silicone oil (B) of this hydrophobic inorganic fine particle b was 18% by mass. In the measurement of the degree of hydrophobicity, even when the methanol concentration is 90% by volume, the whole amount of the hydrophobic inorganic fine particles is not suspended in the solution, and a part of the hydrophobic inorganic fine particles remain floating on the liquid surface. there were. Further, this hydrophobic inorganic fine particle b had a BET specific surface area of 130 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles b.

(Production example 3 of hydrophobic inorganic fine particles)
Untreated dry silica (average primary particle size = 8 nm, BET specific surface area 300 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 250 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 20 parts by mass of dimethyl silicone oil (viscosity = 50 mm ² / s) and water vapor were sprayed as 100 parts by mass of the silica base material as silicone oil (A). The stirring was continued for 2 hours, and the first silicone oil treatment was completed.

  Thereafter, 30 parts by mass of hexamethyldisilazane was sprayed into the interior together with water vapor with respect to 100 parts by mass of the silica raw material, and the mixture was processed in a fluidized state while stirring. This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane and by-products from the hydrophobic silica. The immobilization rate of the first treated silicone oil (A) was 81% by mass.

Further, 15 parts by mass of dimethyl silicone oil (viscosity = 200 mm ² / s) as a silicone oil (B) was sprayed on 100 parts by mass of the silica base while stirring the reaction vessel, and the mixture was stirred for 2 hours. After completion, hydrophobic inorganic fine particles c used in the present invention were obtained.

The immobilization rate of the silicone oil (B) of the hydrophobic inorganic fine particles c was 24% by mass. In the measurement of the degree of hydrophobicity, even when the methanol concentration is 90% by volume, the whole amount of the hydrophobic inorganic fine particles is not suspended in the solution, and a part of the hydrophobic inorganic fine particles remain floating on the liquid surface. there were. Further, this hydrophobic inorganic fine particle c had a BET specific surface area of 240 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles c.

(Production Example 4 of hydrophobic inorganic fine particles)
Untreated dry silica (average primary particle size = 12 nm, BET specific surface area 200 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 250 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 15 parts by mass of dimethyl silicone oil (viscosity = 100 mm ² / s) and water vapor were sprayed as silicone oil (A) on 100 parts by mass of the silica raw material. The stirring was continued for 2 hours, and the first silicone oil treatment was completed.

  Thereafter, 30 parts by mass of hexamethyldisilazane was sprayed into the interior together with water vapor with respect to 100 parts by mass of the silica raw material, and the mixture was processed in a fluidized state while stirring. This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane and by-products from the hydrophobic silica to obtain hydrophobic inorganic fine particles d used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles d of the silicone oil (A) was 83% by mass. In the measurement of the degree of hydrophobicity, the methanol concentration was 88% by volume, and the entire amount of hydrophobic inorganic fine particles was suspended in the solution. Further, this hydrophobic inorganic fine particle d had a BET specific surface area of 150 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles d.

(Hydrophobic inorganic fine particle production example 5)
Untreated dry silica (average primary particle size = 16 nm, BET specific surface area 130 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 200 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 15 parts by mass of dimethyl silicone oil (viscosity = 100 mm ² / s) and water vapor were sprayed as silicone oil (A) on 100 parts by mass of the silica raw material. The stirring was continued for 2 hours, and the first silicone oil treatment was completed.

  Thereafter, 30 parts by mass of hexamethyldisilazane was sprayed into the interior together with water vapor with respect to 100 parts by mass of the silica raw material, and the mixture was processed in a fluidized state while stirring. This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane and by-products from the hydrophobic silica to obtain hydrophobic inorganic fine particles e used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles e of the silicone oil (A) was 64% by mass. In the measurement of the degree of hydrophobicity, the methanol concentration was 87% by volume, and the entire amount of hydrophobic inorganic fine particles was suspended in the solution. Further, this hydrophobic inorganic fine particle e had a BET specific surface area of 90 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles e.

(Hydrophobic inorganic fine particle production example 6)
Untreated dry silica (average primary particle size = 16 nm, BET specific surface area 130 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 200 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas and the reactor was sealed, and 25 parts by mass of dimethyl silicone oil (viscosity = 100 mm ² / s) was sprayed as silicone oil (A) to 100 parts by mass of the silica base. Stirring was continued for 2 hours to complete the first silicone oil treatment.

  Thereafter, 30 parts by mass of hexamethyldisilazane was sprayed inside with respect to 100 parts by mass of the silica raw material, and the treatment was performed in a fluidized state while stirring. This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane and by-products from the hydrophobic silica to obtain hydrophobic inorganic fine particles f used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles f of the silicone oil (A) was 55% by mass. In the measurement of the degree of hydrophobicity, the methanol concentration was 87% by volume, and the entire amount of hydrophobic inorganic fine particles was suspended in the solution. Further, the hydrophobic inorganic fine particle f had a BET specific surface area of 70 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles f.

(Hydrophobic inorganic fine particle production example 7)
Untreated dry silica (average primary particle size = 7 nm, BET specific surface area 380 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 150 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 10 parts by mass of dimethyl silicone oil (viscosity = 200 mm ² / s) was sprayed as silicone oil (A) on 100 parts by mass of the silica raw material. Stirring was continued for 2 hours to complete the first silicone oil treatment.

  Thereafter, 30 parts by mass of hexamethyldisilazane was sprayed inside with respect to 100 parts by mass of the silica raw material, and the treatment was performed in a fluidized state while stirring. This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane and by-products from the hydrophobic silica to obtain hydrophobic inorganic fine particles g used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles g of the silicone oil (A) was 42% by mass. In the measurement of the degree of hydrophobicity, the methanol concentration was 86% by volume, and the entire amount of hydrophobic inorganic fine particles was suspended in the solution. Further, this hydrophobic inorganic fine particle g had a BET specific surface area of 320 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles g.

(Hydrophobic inorganic fine particle production example 8)
Untreated dry silica (average primary particle size = 7 nm, BET specific surface area 380 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 150 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 5 parts by mass of dimethyl silicone oil (viscosity = 200 mm ² / s) was sprayed as silicone oil (A) on 100 parts by mass of the silica raw material. Stirring was continued for 2 hours to complete the first silicone oil treatment.

  Thereafter, 30 parts by mass of hexamethyldisilazane was sprayed inside with respect to 100 parts by mass of the silica raw material, and the treatment was performed in a fluidized state while stirring. This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane and by-products from the hydrophobic silica to obtain hydrophobic inorganic fine particles h used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles h of the silicone oil (A) was 37% by mass. In the measurement of the degree of hydrophobicity, the methanol concentration was 84% by volume, and the entire amount of hydrophobic inorganic fine particles was suspended in the solution. Further, this hydrophobic inorganic fine particle h had a BET specific surface area of 340 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles h.

(Production Example 9 of hydrophobic inorganic fine particles)
Untreated dry silica (average primary particle size = 7 nm, BET specific surface area 380 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 150 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 5 parts by mass of dimethyl silicone oil (viscosity = 200 mm ² / s) was sprayed as silicone oil (A) on 100 parts by mass of the silica raw material. Stirring was continued for 2 hours to complete the first silicone oil treatment.

  Thereafter, 15 parts by mass of hexamethyldisilazane and 10 parts by mass of dimethyldichlorosilane were sprayed inside with respect to 100 parts by mass of the silica raw material, and the mixture was processed in a fluidized state while stirring. This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave is depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane, dichlorodimethylsilane, and by-products from the hydrophobic silica, and the hydrophobic inorganic fine particles i used in the present invention are removed. Obtained.

The immobilization ratio of the hydrophobic inorganic fine particles i of the silicone oil (A) was 36% by mass. In the measurement of the degree of hydrophobicity, the methanol concentration was 83% by volume, and the entire amount of hydrophobic inorganic fine particles was suspended in the solution. Furthermore, this hydrophobic inorganic fine particle i had a BET specific surface area of 350 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles i.

(Hydrophobic inorganic fine particle production example 10)
Untreated dry silica (average primary particle size = 7 nm, BET specific surface area 380 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 150 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 5 parts by mass of dimethyl silicone oil (viscosity = 200 mm ² / s) was sprayed as silicone oil (A) on 100 parts by mass of the silica raw material. Stirring was continued for 2 hours to complete the first silicone oil treatment.

  Thereafter, 20 parts by mass of dimethyldichlorosilane was sprayed inside with respect to 100 parts by mass of the silica base material, and the mixture was treated in a fluidized state while stirring. This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess dichlorodimethylsilane and by-products from the hydrophobic silica to obtain hydrophobic inorganic fine particles j used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles j of the silicone oil (A) was 36% by mass. In the measurement of the degree of hydrophobicity, the methanol concentration was 82% by volume, and the entire amount of hydrophobic inorganic fine particles was suspended in the solution. Furthermore, this hydrophobic inorganic fine particle j had a BET specific surface area of 360 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles j.

(Comparative hydrophobic inorganic fine particle production example 1)
Untreated dry silica (average primary particle size = 7 nm, BET specific surface area 380 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 100 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas and the reactor was sealed, and 30 parts by mass of hexamethyldisilazane was sprayed inside with respect to 100 parts by mass of the silica raw material, and the treatment was performed in a fluidized state while stirring. . This reaction was continued for 60 minutes, and then the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane and by-products from the hydrophobic silica. Further, 5 parts by mass of dimethyl silicone oil (viscosity = 500 mm ² / s) was sprayed on 100 parts by mass of the silica base while stirring the reaction vessel, and after 2 hours of stirring, the treatment was terminated. The comparative hydrophobic inorganic fine particles k used were obtained.

The comparative hydrophobic inorganic fine particles k had a silicone oil immobilization ratio of 8% by mass. In the measurement of the degree of hydrophobicity, the methanol concentration was 81% by volume, and the entire amount of hydrophobic inorganic fine particles was suspended in the solution. Further, the comparative hydrophobic inorganic fine particle k had a BET specific surface area of 310 m ² / g. Table 1 shows the physical properties of the comparative hydrophobic inorganic fine particles k.

(Example of production of amorphous polyester resin)
In a reaction vessel equipped with a stirrer, a thermometer, a condenser, and a nitrogen gas introduction tube, 65 parts by mass of a bisphenol derivative (R: propylene group x + y = 2.2), 30 parts by mass of terephthalic acid Then, 5 parts by mass of isophthalic acid was added, and 0.05 part by mass of tetrabutoxy titanate was added. The inside of the reaction vessel was depressurized to 10.0 mmHg, and stirred and reacted at a temperature of 220 ° C. for about 3 hours under reduced pressure to obtain an amorphous polyester resin. The glass transition temperature measured using a differential scanning calorimeter (DSC) was 58 ° C., the weight average molecular weight (Mw) by gel permeation chromatography (GPC) measurement was 9,000, and an acetone-toluene mixed solution was prepared according to JIS-K0070. The acid value measured using this was 13 mgKOH / g.

(Production Example 1 of Crystalline Polyester Resin)
In a reaction vessel equipped with a stirrer, a thermometer, a condenser, and a nitrogen gas introduction tube, 100 parts by mass of sebacic acid, 37 parts by mass of dimethyl sodium 5-sulfoisophthalate, 100 parts by mass of 1,6-hexanediol, and dibutyl as a catalyst After putting 0.05 parts by mass of tin oxide, the inside of the container was brought into an inert atmosphere with nitrogen gas, and stirred and reacted at about 180 ° C. for about 3 hours under a nitrogen gas stream. Then, 10 parts by mass of dimethyl terephthalate was added, the temperature was raised to 220 ° C. under reduced pressure, and an additional reaction was performed for 4 hours to obtain a crystalline polyester resin 1.

  The crystalline polyester 1 has a melting point measured by using a differential scanning calorimeter (DSC) of 69 ° C., a weight average molecular weight (Mw) by gel permeation chromatography (GPC) measurement of 16,000, acetone according to JIS-K0070. The acid value measured using the toluene mixed solution was 11 mgKOH / g.

(Production Example 2 of Crystalline Polyester Resin)
In a reaction vessel equipped with a stirrer, a thermometer, a condenser, and a nitrogen gas introduction tube, 100 parts by mass of sebacic acid, 45 parts by mass of dimethyl sodium 5-sulfoisophthalate, 200 parts by mass of 1,10-decanediol, and dibutyl as a catalyst After putting 0.03 part by mass of tin oxide, the inside of the container was brought into an inert atmosphere with nitrogen gas, and the reaction was stirred at about 180 ° C. for about 3 hours under a nitrogen gas stream. Thereafter, 20 parts by mass of dimethyl dodecanedioic acid was added, the temperature was raised to 220 ° C. under reduced pressure, and an additional reaction was performed for 4 hours to obtain crystalline polyester resin 2.

  The crystalline polyester 2 has a melting point measured using a differential scanning calorimeter (DSC) of 78 ° C., a weight average molecular weight (Mw) of 32,000 as measured by gel permeation chromatography (GPC), and acetone according to JIS-K0070. The acid value measured using a toluene mixed solution was 4 mgKOH / g.

(Preparation of resin fine particle dispersion 1)
100 parts by mass of ethyl acetate was added to a 2 L separable flask equipped with a stirring blade, a reflux device, and a decompression device using a vacuum pump, and the air in the system was replaced with nitrogen. Next, while heating the inside of the flask to 60 ° C., 20 parts by mass of the crystalline polyester resin 1 and 100 parts by mass of the amorphous polyester resin 1 were added, stirred, and dissolved. Next, after adding 30 parts by mass of 10% ammonia water, 300 parts by mass of ion-exchanged water was slowly added to this while stirring to emulsify the amorphous polyester resin and the crystalline polyester resin.

  The emulsion was stirred under reduced pressure while maintaining the temperature at 60 ° C., and the decompression was terminated when 190 parts by mass of the emulsion was distilled off. While stirring, the mixture was cooled to room temperature to obtain a resin fine particle dispersion 1. The number average particle diameter of the obtained emulsified resin fine particles was 310 nm.

(Preparation of resin fine particle dispersion 2)
A resin fine particle dispersion 2 was prepared using a disperser in which the amorphous polyester resin 1 was modified from Cavitron CD1010 (manufactured by Eurotech Co., Ltd.) into a high temperature and high pressure type. Specifically, 1 part by mass of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) and 20 parts by mass of amorphous polyester resin 1 are added to 79 parts by mass of ion-exchanged water, and ammonia is added. The pH is adjusted to 8.5, the rotor speed is 60 Hz, the pressure is 5 kg / cm ² , and the heating is performed by a heat exchanger at 140 ° C., the Cavitron is operated, and the number average particle diameter of the resin fine particles is 260 nm. A resin fine particle dispersion 2 was obtained.

(Preparation of resin fine particle dispersion 3)
20 parts by mass of crystalline polyester resin 1 was added to 80 parts by mass of ion-exchanged water, heated to 85 ° C., adjusted to pH 9.0 with ammonia, and heated to 85 ° C. while homogenizer (manufactured by IKA Japan, The resin fine particle dispersion 3 was obtained by dispersing at 8000 rpm for 7 minutes using Ultra Tarax T50). The number average particle diameter of the resin fine particles was 290 nm.

(Preparation of resin fine particle dispersion 4)
A resin fine particle dispersion 4 was obtained in the same manner as in the preparation of the resin fine particle dispersion 3 except that the crystalline polyester resin 2 was used. The number average particle diameter of the resin fine particles was 320 nm.

(Preparation of colorant fine particle dispersion)
・ C. I. Pigment Blue 15: 3 20 parts by mass, anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen R) 2 parts by mass, ion-exchanged water 78 parts by mass Using the above components as a homogenizer (IKA, Ultra Turrax T50) After mixing the pigment with water at 3000 rpm for 2 minutes and further dispersing for 10 minutes at 5000 rpm, the mixture was stirred for one day with a normal stirrer and defoamed, and then the high-pressure impact disperser Ultimateizer (Sugino Co., Ltd.) Using a machine manufactured by Machine Co., Ltd., HJP30006), dispersion was performed at a pressure of 240 MPa for about 1 hour to obtain a colorant fine particle dispersion having a number average particle diameter of the colorant fine particles of 170 nm. Further, the pH of the dispersion was adjusted to 6.5.

(Preparation of release agent fine particle dispersion)
-Paraffin wax (maximum endothermic peak = 75 ° C) 45 parts by mass-Cationic surfactant (Neogen RK, Daiichi Kogyo Seiyaku) 5 parts by mass-Ion-exchanged water 200 parts by mass The above ingredients are heated to 95 ° C and homogenizer After sufficiently dispersing with (IKA's Ultra Turrax T50), it was dispersed with a pressure discharge type gorin homogenizer to obtain a release agent fine particle dispersion having a number average particle size of the release agent fine particles of 220 nm.

(Production Example 1 of Toner Particles)
Resin fine particle dispersion 1 80 parts by weight Colorant fine particle dispersion 70 parts by weight Release agent fine particle dispersion 70 parts by weight Polyaluminum chloride 0.40 parts by weight The above ingredients are placed in a 3 liter round flask and 1.0 parts by weight. % Nitric acid aqueous solution was added to adjust the pH to 3.0. Subsequently, 0.35 parts by mass of polyaluminum chloride was added while dispersing at 3000 rpm with a homogenizer (manufactured by IKA Japan: Ultra Tarax T50), and the dispersion was rotated for 6 minutes at 6500 rpm.

  A stirrer and a mantle heater were installed in the reaction vessel, the number of revolutions of the stirrer was appropriately adjusted so that the slurry was sufficiently stirred, and the temperature was raised to 45 ° C. while measuring the particle size with a Coulter Multisizer. When the weight average particle diameter reached 5.0 μm, the pH was adjusted to 8.0 using a 5% aqueous sodium hydroxide solution, the temperature was raised to 85 ° C. and held for 5 hours.

  Thereafter, the product is cooled, filtered, washed with ion-exchanged water, and when the filtrate has a conductivity of 50 mS or less, cake-like particles are taken out and ion-exchanged 10 times the mass of the particles. It was poured into water and stirred with a three-one motor, and when the particles were sufficiently loosened, the pH was adjusted to 3.8 with a 1.0% nitric acid aqueous solution and held for 10 minutes. Thereafter, filtration and washing with water were performed again, and when the conductivity of the filtrate became 10 mS or less, water flow was stopped and solid-liquid separation was performed. The obtained cake-like particles were pulverized by a sample mill and dried in an oven at 40 ° C. for 24 hours. Further, the obtained powder was pulverized by a sample mill and then further vacuum-dried in an oven at 40 ° C. for 5 hours.

  The particles obtained by drying were finely removed with a classifier (TSP separator; manufactured by Hosokawa Micron Corporation) to adjust the number of particles having an equivalent circle diameter of 0.25 μm or more and less than 1.98 μm to obtain toner particles A.

(Toner particle production example 2)
Toner particles B were obtained in the same manner as in Toner Particle Production 1 except that fine powder was not removed by a classifier.

(Toner particle production example 3)
Resin fine particle dispersion 2 100 parts by weight Resin fine particle dispersion 3 25 parts by weight Colorant fine particle dispersion 70 parts by weight Release agent fine particle dispersion 70 parts by weight Polyaluminum chloride 0.45 parts by weight Other than using the above components In the same manner as in Production Example 2, a toner particle C was obtained.

(Toner particle production example 4)
Resin fine particle dispersion 2 75 parts by weight Resin fine particle dispersion 4 50 parts by weight Colorant fine particle dispersion 70 parts by weight Release agent fine particle dispersion 70 parts by weight Polyaluminum chloride 0.45 parts by weight Other than using the above components In the same manner as in Production Example 2, a toner particle D was obtained.

(Toner particle production example 5)
Resin fine particle dispersion 2 125 parts by weight Colorant fine particle dispersion 70 parts by weight Release agent fine particle dispersion 70 parts by weight Polyaluminum chloride 0.40 parts by weight In the same manner as in Toner Particle Production Example 2 except that the above components are used. Toner particles E were obtained.

(Toner Particle Production Example 6)
Resin fine particle dispersion 2 125 parts by weight Colorant fine particle dispersion 70 parts by weight Release agent fine particle dispersion 70 parts by weight Polyaluminum chloride 0.40 parts by weight Using the above ingredients, the weight average particle diameter was 4.5 μm Toner particles F were obtained in the same manner as in Toner Particle Production Example 2 except that the pH was adjusted to 8.0 using a 5% aqueous sodium hydroxide solution, the temperature was raised to 85 ° C. and held for 1 hour. .

<Example 1>
100 parts by mass of toner particles A and 2 parts by mass of hydrophobic inorganic fine particles a are put into a Henschel mixer (FM-10B; manufactured by Mitsui Mining Co., Ltd.), mixed at 3,500 rpm for 5 minutes, and toner 1 is obtained. Prepared. Table 2 shows the physical properties of Toner 1. This toner was evaluated by the following method.

(Image density stability)
The toner 1 was subjected to image evaluation using a Canon printer LBP5300. The evaluation was carried out by mounting an image output cartridge filled with 160 g of toner 1 as a toner on the cyan station, and mounting a dummy cartridge on the other.

The image density was 23% / 55% RH (normal temperature and normal humidity environment) and 30 ° C./80% RH (high temperature and high humidity environment). Images with a printing rate of 1% were continuously output. Every time 1000 sheets were output, a solid image was output and the image density was measured. Up to 15,000 images were output and evaluated according to the following criteria. The image density was measured by measuring the reflection density of a solid image using an SPI filter with a Macbeth densitometer (Macbeth).
A: Image density 1.40 or more B: Image density 1.35 or more and less than 1.40 C: Image density 1.20 or more and less than 1.35 D: Image density 1.00 or more and less than 1.20 E: Image density Less than 00

(Uneven density)
In the same manner as the evaluation of the image density stability, an image output cartridge filled with 160 g of the toner 1 is used as an accelerated test for long-term storage in a high-temperature and high-humidity environment. For 30 days. After leaving for 30 days, seal the cartridge in a plastic bag and take it out. Immediately before the temperature cools down, move the cartridge to an environment with a temperature of 15 ° C and a humidity of 10%. It was confirmed.

For image output, a Canon printer LBP5300 was used in the same manner as the evaluation of the image density stability. A halftone image was printed on the entire surface of the evaluation paper, and the level of density unevenness was evaluated by the number of occurrences of density unevenness per image and the number of sheets passed until disappearance. It was judged that there was no problem in practical use up to rank C, and that there was a possibility of occurrence in actual use in rank D.
A: No occurrence B: Density unevenness within 2 places per sheet occurs, but disappears when 5 sheets or less pass.
C: Density unevenness occurs at 3 or more and 5 or less per sheet, but disappears when 10 or less sheets are passed.
D: White spots of 6 to 8 spots are generated per sheet, but disappears when 30 sheets or less pass.
E: Density unevenness occurs at 9 or more locations per sheet, and does not disappear even when 30 sheets are passed.

  Also, in order to confirm the influence of dew condensation in the toner container of the cartridge, the cartridge left for 30 days in an environment of temperature 40 ° C. and humidity 95% is moved to the environment of temperature 30 ° C. and humidity 80% in the same way and the density is changed. Although unevenness was confirmed, no density unevenness occurred with any of the toners. From this result, it was confirmed that this evaluation was able to monitor the change in image quality due to changes in the usage environment.

(Image flow)
In the same manner as the image density stability test, printing was performed at 30 ° C./80% RH (high temperature and high humidity environment) using a Canon printer LBP5300, and the power was turned off after passing 5,000 sheets. Left for days. After being left, a character pattern image with a printing ratio of 5% is output. The output images were confirmed, and the following ranking was performed according to the number of output images required for image output until the image flow disappeared.
A: No occurrence B: Less than 5 sheets disappeared C: 5 to less than 10 sheets disappeared D: 10 to less than 20 sheets disappeared E: Disappeared from 20 sheets or more

  The evaluation results of these toners 1 are shown in Table 2.

<Examples 2 to 14 and Comparative Examples 1 and 2>
As shown in Table 2, toners 2 to 16 were prepared in the same manner as in Example 1 except that toner particles and hydrophobic inorganic fine particles were combined. Table 2 shows the physical properties of Toners 2 to 16.

  These toners 2 to 16 were evaluated in the same manner as toner 1. The evaluation results are shown in Table 2.

Claims (7)

In a toner having toner particles containing at least a binder resin, a colorant and a release agent, and hydrophobic inorganic fine particles,
The hydrophobic inorganic fine particles are hydrophobic inorganic fine particles that have been surface-treated with a silane compound and / or a silazane compound after the surface treatment with silicone oil (A),
The toner particles are toner particles obtained by an emulsion aggregation method,
The toner particles contain at least a polyester resin as a main component,
In a flow type particle image measuring apparatus with an image processing resolution of 512 × 512 pixels (0.19 μm × 0.19 μm per pixel), the equivalent circle diameter for the number of particles having an equivalent circle diameter of 0.25 μm to less than 39.5 μm. A toner having a ratio of the number of particles of 0.25 μm or more and less than 1.98 μm of 1.0 to 30.0% by number.   2. The toner particles according to claim 1, wherein the toner particles contain at least a crystalline polyester resin, and the content of the crystalline polyester resin is 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the binder resin. The toner described.   The hydrophobic inorganic fine particles are characterized in that, in a wettability test with respect to a methanol / water mixed solvent, the total amount of the hydrophobic inorganic fine particles is such that the concentration of methanol suspended in the solution is 86% by volume or more. 2. The toner according to 2. The toner according to claim 1, wherein the hydrophobic inorganic fine particles have a BET specific surface area of 50 m ² / g or more and 300 m ² / g or less.   The hydrophobic inorganic fine particles are hydrophobic inorganic fine particles that are surface-treated with a silicone oil (A), surface-treated with a silane compound and / or a silazane compound, and further surface-treated with a silicone oil (B). The toner according to claim 1.   In the hydrophobic inorganic fine particles, the treatment amount of the silicone oil (A) is 10 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the inorganic fine particle raw material, and the immobilization rate of the silicone oil (A) The toner according to claim 1, wherein the toner is 60% by mass or more.   In the hydrophobic inorganic fine particles, the treatment amount of the silicone oil (B) is 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the inorganic fine particle base material, and the immobilization rate of the silicone oil (B) The toner according to claim 5, wherein the toner is 40% by mass or less.