JP5344612B2 - toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner which maintains excellent developability even after being subjected to a heat cycle in a high temperature and high humidity environment, and prevents fading due to fusion of a sleeve or degradation in fluidity. <P>SOLUTION: The toner includes toner particles containing a binder resin, a colorant and wax, and hydrophobic inorganic fine particles. The toner particles are obtained by granulating a mixture solution in an aqueous medium, the mixture solution prepared by dissolving a binder resin essentially comprising a polyester resin, a colorant and wax in an organic solvent, and then removing the organic solvent. The hydrophobic inorganic particles are surface-treated with a silicone oil (A) and then surface-treated with a silane compound and/or a silazane compound. In a wettability test on the toner with respect to a methanol/water mixture solvent, when the toner shows 50% of transmittance to light at a wavelength of 780 nm, the methanol concentration is not less than 40 vol%. <P>COPYRIGHT: (C)2011,JPO&amp;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.

  In recent years, devices using electrophotography have begun to be used in printers for output of computers, facsimiles, etc., in addition to copying machines for copying original documents. Therefore, further miniaturization, weight reduction, high speed, and high reliability have been strictly pursued, and elements required for toner for performance improvement have been increasing. Under such circumstances, a solution suspension method is used as a method for producing a toner capable of controlling the breadth of material selectivity, the shape, particle size and surface structure of toner particles.

  On the other hand, since the number of cases stored or used in various environments is increasing as the market expands, it is required to maintain the quality at a higher level. For example, in the transportation stage, the temperature may change during the day and night (heat cycle) over a long period of time. Moreover, since temperature and humidity may not be managed in the warehouse or in the usage environment, it may continue to be stored in a harsh environment including a heat cycle. When subjected to a heat cycle, the toner may deteriorate and performance may deteriorate. In addition, when subjected to a heat cycle in a high humidity environment, performance deterioration due to condensation tends to occur. In particular, since the toner particles are produced in an aqueous medium in the dissolution suspension method, the surface of the toner particles may be easily affected by moisture. Under such circumstances, a design that can maintain toner performance even during long-term use and storage is required.

  Patent Documents 1 and 2 disclose an example in which silica having a controlled release rate of silicone oil is externally added to toner particles prepared by a dissolution suspension method. However, there is a possibility that the toner has insufficient hydrophobic resistance, and it is considered that the toner is likely to deteriorate in performance when subjected to a heat cycle under high temperature and high humidity, and there is still room for improvement.

  Patent Document 3 discloses an example in which the hydrophobic relationship between toner and toner particles is controlled. However, since the difference in hydrophobicity between the toner and the toner particles is small, there is a possibility that the performance of the toner is likely to deteriorate when subjected to a heat cycle under high temperature and high humidity.

  Patent Documents 4 and 5 disclose examples in which inorganic fine particles are surface-treated with silicone oil and then subjected to a hydrophobic treatment with a treating agent such as hexamethyldisilazane. This method is easy to immobilize silicone oil on the silica surface, and can increase the hydrophobicity of silica, but suppresses the effect of toner condensation due to environmental fluctuations after undergoing a heat cycle under high temperature and high humidity. The degree of hydrophobicity was insufficient.

  As described above, in order to obtain a toner that can cope with a sudden change in use environment, further contrivance is required for the combination of toner particles and hydrophobic inorganic fine particles.

JP 2004-219609 A JP 2007-079246 A JP 2003-202700 A JP 2002-256170 A JP 2004-168559 A

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

  That is, an object of the present invention is to maintain excellent developability even after being subjected to a heat cycle under high temperature and high humidity, and an image defect due to sleeve fusion or a poor supply of toner due to poor fluidity, and the image is stripped. It is an object of the present invention to provide a toner that is less prone to fading.

  In order to achieve the above object, a first invention according to the present application provides a toner particle containing at least a binder resin, a colorant, and a wax, and a toner containing hydrophobic inorganic fine particles. A mixed solution in which a toner composition containing at least a binder resin containing a resin as a main component, a colorant, and a wax is dissolved or dispersed in an organic solvent is granulated in an aqueous medium, and the organic solvent is removed. The hydrophobic inorganic fine particles are hydrophobic inorganic fine particles which are surface-treated with a silicone oil (A) and then surface-treated with a silane compound and / or a silazane compound. In the wettability test with respect to a water mixed solvent, the methanol concentration when the light transmittance at a wavelength of 780 nm is 50% is 40% by volume or more. A toner.

  In order to achieve the above object, a second invention according to the present application is a toner in which the binder resin contains a modified polyester having urethane and / or urea groups.

  In order to achieve the above object, the third invention according to the present application is directed to the hydrophobic inorganic fine particles when the whole amount of the hydrophobic inorganic fine particles is suspended in a solution in a wettability test for a methanol / water mixed solvent. A toner having a methanol concentration of 86% by volume or more.

In order to achieve the above object, a fourth invention according to the present application is a toner 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.

  In order to achieve the above object, according to a fifth invention of the present application, the hydrophobic inorganic fine particles are subjected to a surface treatment with a silicone oil (A), followed by a surface treatment with a silane compound and / or a silazane compound. The toner is a hydrophobic inorganic fine particle surface-treated according to B).

  In order to achieve the above object, according to a sixth invention of the present application, the hydrophobic inorganic fine particles have a treatment amount of the silicone oil (A) of 10 to 30 parts by mass with respect to 100 parts by mass of the inorganic fine particle base. And a fixing ratio of the silicone oil (A) is 60% by mass or more.

  In order to achieve the above object, according to a seventh invention of the present application, the hydrophobic inorganic fine particles have a treatment amount of the silicone oil (B) of 1 part by mass or more and 10 parts by mass with respect to 100 parts by mass of the inorganic fine particle precursor. And a fixing ratio of the silicone oil (B) is 40% by mass or less.

  According to the present invention, it is possible to obtain a toner that maintains excellent developability even after being subjected to a heat cycle under high temperature and high humidity, and is less likely to cause fading due to sleeve fusion or fluidity deterioration.

2 shows a methanol drop transmittance curve of toner 1.

  Laser beam printers and the like are increasingly being stored or used in various environments as the market expands. For example, in the transportation stage, the temperature may change during the day and night (heat cycle) over a long period of time. Moreover, since temperature and humidity may not be managed in the warehouse or in the usage environment, it may continue to be stored in a harsh environment including a heat cycle. In particular, when subjected to a heat cycle under high temperature and high humidity, the toner deteriorates in cohesiveness, fading easily occurs due to sleeve fusion and fluidity deterioration, and developability may also be reduced.

As a result of investigations by the present inventors on these problems, at least toner particles containing a binder resin, a colorant, and a wax, and a toner containing hydrophobic inorganic fine particles,
The toner particles are prepared by granulating a mixed solution in which a toner composition containing at least a binder resin mainly composed of a polyester resin, a colorant, and a wax is dissolved or dispersed in an organic solvent in an aqueous medium, Toner particles obtained by removing the organic solvent,
The hydrophobic inorganic fine particles are hydrophobic inorganic fine particles surface-treated with a silane compound and / or a silazane compound after surface treatment with silicone oil (A),
In the wettability test of the toner in a methanol / water mixed solvent, the methanol concentration when the light transmittance at a wavelength of 780 nm is 50% is 40% by volume or higher under the high temperature and high humidity which is the object of the present invention. It has been found that fading due to sleeve fusion and fluidity deterioration can be suppressed while maintaining excellent developability after being subjected to a heat cycle.

  The toner particles used in the present invention are prepared by mixing a mixed solution obtained by dissolving or dispersing a toner composition containing at least a binder resin mainly composed of a polyester resin, a colorant, and a wax in an organic solvent in an aqueous medium. It is obtained by granulating and removing the organic solvent. Since the toner particles obtained by this production method have a high degree of circularity and the surface can be controlled to an appropriate roughness, there is an advantage of excellent electrophotographic characteristics. In addition, by devising hydrophobic inorganic fine particles added to toner particles, excellent developability is maintained even when subjected to heat cycles under high temperature and high humidity, and fading due to sleeve fusing and fluidity deterioration is also good Become. This is because the toner particle surface and the silicone oil (A) are strong and held so as to cover the toner particle surface by the polar group on the surface of the toner particle containing the binder resin whose main component is a polyester resin. It is considered that very high hydrophobicity can be obtained.

  The toner used in the present invention is characterized in that, in a wettability test for a methanol / water mixed solvent, the methanol concentration when the light transmittance at a wavelength of 780 nm is 50% is 40% by volume or more. When the methanol concentration is 40% by volume or more, the hydrophobicity of the toner is high, and developability is maintained even when subjected to a heat cycle under high temperature and high humidity, and sleeve fusion and fading can be suppressed.

  When the light transmittance at a wavelength of 780 nm is 50% and the methanol concentration is less than 40% by volume, the hydrophobicity of the toner is low, so that the toner tends to absorb moisture when subjected to a heat cycle under high temperature and high humidity. Therefore, developability is lowered, toner is likely to aggregate, and sleeve fusion or fading may occur.

  The hydrophobic inorganic fine particles used in the present invention are inorganic fine particles that have been surface treated with a silane compound and / or a silazane compound after the surface treatment with the silicone oil (A). Hydrophobic inorganic fine particles treated in this way have a very high degree of hydrophobicity, so by combining with toner particles prepared in an aqueous medium, sleeve fusion after being subjected to a heat cycle under high temperature and high humidity In addition, it exerts a great effect on suppressing fading due to deterioration of fluidity and maintains excellent developability.

  When the inorganic fine particles are hydrophobized, the silicone oil (A) is first fixed on the surface of the inorganic fine particles by treating with the silicone oil (A) and then with the silane compound and / or silazane compound. In this state, the degree of hydrophobicity on the surface of the inorganic fine particles can be made higher than ever. What is important here is that inorganic particles that have not been hydrophobized are treated with silicone oil (A).

  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.

  When the inorganic fine particles are first treated with a silane compound and / or a silazane compound, they cannot react with all the adjacent hydroxyl groups present on the surface of the inorganic fine particles, and hydroxyl groups that are not hydrophobized tend to remain. This is because the hydrophobic group introduced into the surface of the inorganic fine particles by these compounds has a large molecular size and steric hindrance. Even if the surface treatment is performed with silicone oil after this treatment, the silicone oil is difficult to be immobilized on the surface of the inorganic fine particles because of the small number of hydroxyl groups on the surface of the inorganic fine particles. As a result, hydroxyl groups that are not hydrophobized remain on the surface of the inorganic fine particles, so that when the toner is externally added to the toner particles and subjected to a heat cycle under high temperature and high humidity, the toner tends to absorb moisture, resulting in a decrease in developability and aggregation of the toner. It becomes easy and sleeve fusion and fading may occur.

  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. When the methanol concentration is 86% by volume or more, the hydrophobicity is very high. Immediately after undergoing a heat cycle under high temperature and high humidity, even when moving to low temperature and low humidity and printing, the white haze that causes white spots on the image due to toner agglomerates generated due to dew condensation is easy to improve .

  If the methanol concentration is less than 86% by volume, the hydrophobicity is insufficient, and if it moves to low temperature and low humidity immediately after being subjected to a heat cycle under high temperature and high humidity, white haze is likely to occur. Become.

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 is 50 m ² / g or more and 300 m ² / g or less, the chargeability of the toner is good. Therefore, even in long-term image output after being subjected to a heat cycle under high temperature and high humidity, fog is not generated. Easy to improve.

If the BET specific surface area of the surface of the inorganic fine particles is less than 50 m ² / g, it is disadvantageous for the deterioration of the toner, resulting in poor charging in long-term image output after being subjected to a heat cycle under high temperature and high humidity. The fog is likely to deteriorate and the developability is also likely to deteriorate. When the BET specific surface area of the surface of the inorganic fine particles is larger than 300 m ² / g, the charge distribution tends to be broad and the fog tends to deteriorate.

  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, good developability is maintained even when image formation is performed under high temperature and high humidity, and the photosensitive member is less likely to be fused.

  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, it is possible to drastically improve photoreceptor fusion while maintaining developability without reducing toner fluidity or degrading chargeability. become.

  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 processing amount of the silicone oil (A) within this range, the hydrophobicity of the hydrophobic inorganic fine particles becomes sufficiently high, and maintains excellent developability even after being subjected to a heat cycle under high temperature and high humidity. Sleeve fusion is less likely to occur.

  When the treatment amount of the silicone oil (A) is less than 10 parts by mass with respect to 100 parts by mass of the inorganic fine particle base material, the hydrophobicity of the hydrophobic inorganic fine particles is not sufficiently increased, and the developability is lowered or the sleeve is fused. May get worse. When the amount is more than 30 parts by mass, the silicone oil becomes excessive, and the fluidity of the toner is lowered, so that developability and fading may be deteriorated. Further, when the immobilization ratio of the silicone oil (A) to the hydrophobic inorganic fine particles is less than 60% by mass, the hydrophobicity of the hydrophobic inorganic fine particles becomes insufficient, resulting in poor developability and poor sleeve fusion. There is a case.

  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). The presence of moisture or water vapor during the treatment increases the concentration of hydroxyl groups on the surface of the inorganic fine particles, so that the dehydration reaction from the hydroxyl groups on the surface of the inorganic fine particles is likely to occur. And the site | part by which silicone oil is fixed increases, and it becomes easier to fix silicone oil to the inorganic fine particle surface.

  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. By placing the inorganic fine particles treated with the silicone oil (A) in the presence of water vapor, the concentration of hydroxyl groups in the fine recesses on the surface of the fine inorganic particles into which the silicone oil (A) has not entered is increased. 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 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 silicone oil (B) is fixed. The conversion rate 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, It shows a great effect in suppressing photoconductor fusion.

  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 amount of the silane compound and / or silazane compound is less than 1 part by mass, the degree of hydrophobicity is lowered, and there is a possibility that density unevenness and image flow are deteriorated. When the amount is more than 50 parts by mass, the unreacted silane compound and / or silazane compound may remain on the surface of the inorganic fine particles, which may deteriorate the chargeability of the toner.

  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 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.

The particle size of the BET specific surface area of 10 m ² / g smaller than inorganic fine particles of the inorganic fine particles is increased, that the toner particle surfaces uniformly cover difficult. If the BET specific surface area of the inorganic fine particles is larger than 500 m ² / g, it is difficult to perform the hydrophobic treatment uniformly and the degree of hydrophobicity tends to decrease.

  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, etc., selected from silica, titanium oxide, alumina, or their suboxides to improve developability and fluidity Is preferred.

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. If it is less than 5 mm ² / s, sufficient hydrophobicity may not be obtained. If it exceeds 2,000 mm ² / s, it becomes difficult to uniformly treat the inorganic fine particles, and aggregates are easily formed and sufficient flow is achieved. Sexuality may not 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, dimethyldiethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyl Disiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxa And dimethylpolysiloxane containing 2 to 12 siloxane units per molecule and containing hydroxyl groups 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. In particular, in order to achieve the effect of the present invention, a silazane compound is preferably used, and hexamethyldisilazane is particularly 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 subjected to a hydrophobic treatment, 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 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, the silicone oil (B) is preferably uniformly adhered in a small amount in a state where it is not immobilized on the surface of the inorganic fine particles. For this reason, a method of dissolving or dispersing the silicone oil (B) in an appropriate solvent, mixing it with the base inorganic 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.

  A simple method for preparing the toner particles used in the present invention will be described, but is not limited thereto.

  The toner particles include at least a binder resin mainly composed of a polyester resin, a colorant, and a wax in an aqueous medium in which resin fine particles having a function as a dispersant are dispersed (hereinafter also referred to as an aqueous phase). The toner composition is preferably obtained by granulating a mixed solution (hereinafter also referred to as an oil phase) obtained by dissolving or dispersing the toner composition in an organic solvent in an aqueous medium, removing the organic solvent, and drying.

  In the method for preparing the oil phase, the following can be used as an organic medium for dissolving a binder resin mainly composed of a polyester resin, a colorant, wax and the like.

  Hydrocarbon solvents such as ethyl acetate, xylene and hexane, halogenated hydrocarbon solvents such as methylene chloride, chloroform and dichloroethane, ester solvents such as methyl acetate, ethyl acetate, butyl acetate and isopropyl acetate, ethers such as diethyl ether Examples of the solvent include ketone solvents such as acetone, methyl ethyl ketone, diisobutyl ketone, cyclohexanone, and methylcyclohexane.

  The binder resin mainly composed of a polyester resin is used in the form of a resin dispersion dissolved in the organic medium. In this case, although it depends on the viscosity and solubility of the resin, in consideration of ease of production in the next step, as a resin component in the organic solvent, a polyester resin as a main component in a range of 40% by mass to 60% by mass. It is preferable to blend a resin. In addition, heating at the melting point or lower of the organic medium at the time of dissolution is preferable because the solubility of the resin increases.

  The wax and the colorant are also preferably dispersed in the organic medium. That is, it is preferable to disperse a wax and a colorant, which are previously wet or dry mechanically pulverized, in an organic medium to prepare a wax dispersion and a colorant dispersion, respectively.

  The dispersibility of the wax and the colorant can also be improved by adding a dispersant and resin that match each of them. Since these differ depending on the wax, colorant, resin, and organic solvent used, they can be selected and used as appropriate.

  The oil phase can be prepared by blending a desired amount of the resin dispersion, wax dispersion, colorant dispersion, and organic medium, and dispersing the components in the organic medium.

  The binder resin used in the present invention is characterized by containing a polyester resin as a main component. By adding the hydrophobic inorganic fine particles of the present invention to toner particles containing polyester as a main component, it becomes highly hydrophobic and easily maintains high chargeability. As a result, even when subjected to a heat cycle under high temperature and high humidity, excellent developability is maintained, and fading due to sleeve fusion and fluidity deterioration becomes good.

  The polyester resin used in the present invention mainly comprises polyvalent carboxylic acids and polyhydric alcohols. Examples of the polyvalent carboxylic acids include terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, diphenic acid, sulfoterephthalic acid, 5-sulfoisophthalic acid, and 4-sulfophthalic acid. Acid, 4-sulfonaphthalene-2,7 dicarboxylic acid, 5 (4-sulfophenoxy) isophthalic acid, sulfoterephthalic acid, and / or their metal salts, ammonium salts and other aromatic dicarboxylic acids, p-oxybenzoic acid, p -Aromatic oxycarboxylic acids such as (hydroxyethoxy) benzoic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid and other aliphatic dicarboxylic acids, fumaric acid, maleic acid, itaconic acid, hexahydrophthalic acid , Unsaturated aliphatics such as tetrahydrophthalic acid, and fats The family dicarboxylic acids, etc., and other trimellitic acid as a polycarboxylic acid, trimesic acid, trihydric or higher polycarboxylic acids such as pyromellitic acid.

  Examples of the polyhydric alcohols include aliphatic polyhydric alcohols, alicyclic polyhydric alcohols, and aromatic polyhydric alcohols. Aliphatic polyhydric alcohols include ethylene glycol, propylene glycol, 1,3-propanediol, 2,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, Neopentyl glycol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl-1,3-pentanediol, aliphatic diols such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, trimethylolethane, trimethylolpropane, Examples include triols and tetraols such as glycerin and pentaelsitol.

  Alicyclic polyhydric alcohols include 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, spiroglycol, hydrogenated bisphenol A, ethylene oxide adduct and propylene oxide adduct of hydrogenated bisphenol A, tricyclodecane Examples thereof include diol and tricyclodecane dimethanol.

  As aromatic polyhydric alcohols, para-xylene glycol, meta-xylene glycol, ortho-xylene glycol, 1,4-phenylene glycol, ethylene oxide adduct of 1,4-phenylene glycol, bisphenol A, ethylene oxide addition of bisphenol A And propylene oxide adducts. Furthermore, examples of polyester polyols include lactone polyester polyols obtained by ring-opening polymerization of lactones such as ε-caprolactone.

  A monofunctional monomer may be introduced into the polyester for the purpose of blocking the polar group at the end of the polyester polymer and improving the developability of toner charging characteristics. Monofunctional monomers include benzoic acid, chlorobenzoic acid, bromobenzoic acid, parahydroxybenzoic acid, sulfobenzoic acid monoammonium salt, sulfobenzoic acid monosodium salt, cyclohexylaminocarbonylbenzoic acid, n-dodecylaminocarbonylbenzoic acid Acid, tert-butylbenzoic acid, naphthalenecarboxylic acid, 4-methylbenzoic acid, 3-methylbenzoic acid, salicylic acid, thiosalicylic acid, phenylacetic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, octanecarboxylic acid, lauric acid, stearyl Examples thereof include monocarboxylic acids such as acids and lower alkyl esters thereof, or monoalcohols such as aliphatic alcohols, aromatic alcohols, and alicyclic alcohols.

  The binder resin used in the present invention is preferably modified, and particularly preferably contains a modified polyester having urethane and / or urea groups.

  By containing the modified polyester, the chargeability of the toner particle surface is improved. Therefore, even immediately after being subjected to a heat cycle under high temperature and high humidity, the rise of charge is good and sufficient developability is easily obtained from the beginning.

  Examples of the modified polyester having a urethane and / or urea group include a urethane group-containing polyester resin obtained by reacting a polyester resin with an isocyanate, and a urea group-containing polyester resin obtained by reacting an isocyanate group-containing polyester resin with an amino compound. .

  The modified polyester having a urethane and / or urea group may be added to the oil phase in advance as in the toner composition containing at least a binder resin mainly composed of a polyester resin, a colorant, and a wax. When granulating inside, it may be modified to a polyester having urethane and / or urea groups.

  The urethane group-containing polyester resin used in the present invention will be described.

  The urethane group-containing polyester resin contains a reaction product of a diol component and an isocyanate component.

  Examples of the diisoacinate component include the following.

  C6-C20 aromatic diisocyanate, C2-C18 aliphatic diisocyanate, C4-C15 alicyclic diisocyanate, C8-C15 aromatic Group hydrocarbon diisocyanates and modified products of these diisocyanates (urethane group, carbodiimide group, allophanate group, urea group, burette group, uretdione group, uretoimine group, isocyanurate group, oxazolidone group-containing modified product, hereinafter also referred to as modified diisocyanate) As well as a mixture of two or more of these.

  The following are mentioned as said aromatic diisocyanate.

  1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 1,5-naphthylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate (TDI), crude TDI, 2,4′-diphenylmethane Diisocyanate, 4,4′-diphenylmethane diisocyanate (MDI), crude MDI [crude diaminophenylmethane [condensation product of formaldehyde and aromatic amine (aniline) or a mixture thereof]].

  Examples of the aliphatic diisocyanate include the following.

  Ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecane triisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethyl carbonate Proate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexanoate.

  Examples of the alicyclic diisocyanate include the following.

  Isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4′-diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis (2-isocyanatoethyl) -4-cyclohexene-1, 2-dicarboxylate, 2,5-norbornane diisocyanate, 2,6-norbornane diisocyanate.

  Examples of the aromatic hydrocarbon diisocyanate include the following.

  m-xylylene diisocyanate, p-xylylene diisocyanate (XDI), α, α, α ′, α′-tetramethylxylylene diisocyanate (TMXDI).

  Examples of the modified diisocyanate include the following.

  Modified MDI (urethane-modified MDI, carbodiimide-modified MDI, trihydrocarbyl phosphate-modified MDI), urethane-modified TDI, and the like, and mixtures of two or more thereof (for example, modified MDI and urethane-modified TDI (isocyanate-containing prepolymer)) Combination of].

  Of these, preferred are aromatic diisocyanates having 6 to 15 carbon atoms, aliphatic diisocyanates having 4 to 12 carbon atoms, and alicyclic diisocyanates having 4 to 15 carbon atoms, and particularly preferred are TDI, MDI, HDI, water. Attached MDI and IPDI.

  Moreover, in addition to the above-mentioned diisocyanate component, a trifunctional or higher functional isocyanate compound can also be used for the urethane group-containing polyester resin. Examples of the trifunctional or higher functional isocyanate compound include polyallyl polyisocyanate (PAPI), 4,4 ′, 4 ″ -triphenylmethane triisocyanate, m-isocyanatophenylsulfonyl isocyanate, and p-isocyanatophenylsulfonyl isocyanate. Is mentioned.

  Moreover, the following are mentioned as a diol component which can be used for a urethane group containing polyester resin.

Alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, octanediol, decanediol, dodecanediol, tetradecanediol, neopentyl glycol, 2,2-diethyl-1,3-propanediol);
Alkylene ether glycol (diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol);
Alicyclic diols (such as 1,4-cyclohexanedimethanol, hydrogenated bisphenol A);
Bisphenols (bisphenol A, bisphenol F, bisphenol S, etc.);
Alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol;
Alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adducts of the above bisphenols;
In addition, polylactone diol (such as poly ε-caprolactone diol), polybutadiene diol.

  The alkyl part of the above-described alkylene ether glycol may be linear or branched. In the present invention, an alkylene glycol having a branched structure can also be preferably used.

  Among these, an alkyl structure is preferable in view of solubility (affinity) in ethyl acetate, and an alkylene glycol having 2 to 12 carbon atoms is preferably used.

  In the urethane group-containing polyester resin, in addition to the diol component described above, a polyester oligomer having a terminal hydroxyl group (terminal diol polyester oligomer) can also be used as a suitable diol component.

  Moreover, the terminal diol polyester oligomer mentioned above may have an ether bond modified with ethylene oxide, propylene oxide or the like.

  The urea group-containing polyester resin used in the present invention will be described.

  The urea group-containing polyester resin is obtained by reacting an isocyanate group-containing polyester resin with an amino compound.

  The following are mentioned as said amino compound.

  Diaminoethane, diaminopropane, diaminobutane, diaminohexane, piperazine, 2,5-dimethylpiperazine, amino-3-aminomethyl-3,5,5-trimethylcyclohexane (isophoronediamine, IPDA), 4,4'-diaminodicyclohexyl Diamines such as methane, 1,4-diaminocyclohexane, aminoethylethanolamine, hydrazine, hydrazine hydrate.

  Triamines such as triethylamine, diethylenetriamine and 1,8-diamino-4-aminomethyloctane.

  The aqueous phase will be described. The toner particles include a toner composition containing at least a binder resin mainly composed of a polyester resin, a colorant, and a wax in an organic solvent in an aqueous medium in which resin fine particles having a function as a dispersant are dispersed. Add the dissolved or dispersed mixed solution and granulate.

  As the resin fine particles used in the present invention, any resin can be used as long as the oil phase can be dispersed in the water phase. Specific examples include vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimide resins, silicon resins, phenol resins, melamine resins, urea resins, aniline resins, ionomer resins, polycarbonate resins, and the like. The resin fine particles may be a combination of two or more of the above resins. Among these, those made of a vinyl resin, a polyurethane resin, an epoxy resin, a polyester resin, and a resin using a combination thereof are preferable because an aqueous dispersion of fine spherical resin particles is easily obtained. The vinyl resin is a polymer obtained by homopolymerization or copolymerization of a vinyl monomer, such as a styrene- (meth) acrylate resin, a styrene-butadiene copolymer, a (meth) acrylic acid-acrylate polymer, Examples include styrene-acrylonitrile copolymers, styrene-maleic anhydride copolymers, styrene- (meth) acrylic acid copolymers, and the like. The average particle diameter of the resin fine particles is 5 to 2000 nm, preferably 20 to 300 nm.

  The aqueous medium may be water alone, but a solvent miscible with water may be used in combination. Examples of miscible solvents include alcohols (methanol, isopropanol, ethylene glycol), dimethylformamide, tetrahydrofuran, cellosolves (methylcellosolve), and lower ketones (acetone, methylethylketone). It is also a preferred method to mix an appropriate amount of the organic medium used as the oil phase in the aqueous medium used in the present invention. This seems to have the effect of enhancing droplet stability during granulation and making the aqueous medium and the oil phase more easily suspended.

  In the present invention, it is preferable to use resin fine particles dispersed in an aqueous medium. The resin fine particles are used in a desired amount according to the stability of the oil phase in the next step. The amount of the resin fine particles used is preferably 2.0 parts by mass or more and 15.0 parts by mass or less with respect to 100 parts by mass of the toner base particles. In the aqueous medium, a known surfactant, dispersant, dispersion stabilizer, water-soluble polymer, or viscosity modifier may be added.

  Examples of the surfactant include an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant. These can be arbitrarily selected according to the polarity at the time of toner particle formation.

  Specifically, anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters; amine salt types such as alkylamine salts, aminoalcohol fatty acid derivatives, polyamine fatty acid derivatives, imidazolines, and alkyltrimethyls. Ammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, quaternary ammonium salt type cationic surfactants such as benzethonium chloride; fatty acid amide derivatives, polyhydric alcohol derivatives, etc. Nonionic surfactants; amphoteric surfactants such as alanine, dodecyl di (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-dimethylammonium betaine.

  The following are mentioned as said dispersing agent.

Acids such as acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride;
Β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloro-2-acrylate Hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N-methylolacrylamide, N-methylolmethacrylamide, etc. (Meth) acrylic monomers containing the hydroxyl groups of
Vinyl alcohol or ethers with vinyl alcohol such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether;
Esters of vinyl alcohol and vinyl-containing compounds such as vinyl acetate, vinyl propionate and vinyl butyrate;
Acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds; acid chlorides such as acrylic acid chloride and methacrylic acid chloride; those having nitrogen atoms such as vinylpyridine, vinylpyrrolidone, vinylimidazole, ethyleneimine, or heterocyclic rings thereof Homopolymers or copolymers such as;
Polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl Polyoxyethylenes such as phenyl ester and polyoxyethylene nonylphenyl ester;
Celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose.

  When a dispersant is used, the dispersant can remain on the surface of the toner particles, but it is preferable to dissolve and remove it from the charged surface of the toner.

  In the present invention, a solid dispersion stabilizer may be used to maintain a more preferable dispersion state.

  In the present invention, it is preferable to use a dispersion stabilizer. The reason is as follows. The organic medium in which the resin binder as the main component of the toner is dissolved has a high viscosity. Therefore, the dispersion stabilizer surrounds the oil droplets formed by finely dispersing the organic medium with a high shearing force, preventing the oil droplets from reaggregating and stabilizing.

  As the dispersion stabilizer, inorganic dispersion stabilizers and organic dispersion stabilizers can be used. In the case of inorganic dispersion stabilizers, toner particles are granulated in a state of being adhered on the particle surface after dispersion, and thus have an affinity for a solvent. Those that can be removed by non-acidic acids such as hydrochloric acid are preferred. For example, calcium carbonate, calcium chloride, sodium hydrocarbon, potassium hydrocarbon, sodium hydroxide, potassium hydroxide, hydroxyapatite, and calcium triphosphate can be used.

  The dispersion method used at the time of preparing the toner particles is not particularly limited, and general-purpose devices such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be used, but the dispersion particle size is 2 to 20 μm. In order to achieve the degree, a high-speed shearing type is preferable.

  If it is a stirrer which has a rotary blade, there will be no restriction | limiting in particular, If it is a general thing as an emulsifier and a disperser, it can be used for the said dispersion | distribution method.

  For example, Ultra Tarrax (manufactured by IKA), Polytron (manufactured by Kinematica), TK Auto Homo Mixer (manufactured by Special Mechanized Industry Co., Ltd.), Ebara Milder (manufactured by Ebara Corporation), TK homomic line flow (Made by Special Machine Industries Co., Ltd.), colloid mill (made by Shinko Pantech Co., Ltd.), thrasher, trigonal wet pulverizer (made by Mitsui Miike Chemical Co., Ltd.), Cavitron (made by Eurotech), fine flow mill Examples thereof include a continuous emulsifier such as (manufactured by Taiheiyo Kiko Co., Ltd.), a batch type of CLEARMIX (manufactured by M Technique Co., Ltd.), a fill mix (manufactured by Tokushu Kika Kogyo Co., Ltd.), or a continuous-use emulsifier.

  When a high-speed shearing disperser is used for the dispersion method, the rotation speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 3000 to 20000 rpm.

  In the case of the batch method, the dispersion time in the dispersion method is usually 0.1 to 5 minutes. The temperature during dispersion is usually 10 to 150 ° C. (under pressure), preferably 10 to 100 ° C.

  In order to remove the organic solvent from the obtained dispersion, a method in which the entire system is gradually heated to completely evaporate and remove the organic solvent in the droplets can be employed.

  Alternatively, the dispersion can be sprayed into a dry atmosphere to completely remove the water-insoluble organic solvent in the droplets to form toner particles, and the water in the dispersion can be removed by evaporation. .

  In that case, as the dry atmosphere in which the dispersion is sprayed, a gas heated with air, nitrogen, carbon dioxide gas, combustion gas, etc., especially various air streams heated to a temperature higher than the boiling point of the highest boiling solvent used are generally used. It is done. Sufficient quality can be obtained even in a short time such as spray dryer, belt dryer or rotary kiln.

  When the particle size distribution of the dispersion obtained by the above dispersion method is wide and washing and drying are performed while maintaining the particle size distribution, the particle size distribution can be adjusted by classifying into a desired particle size distribution.

  The dispersant used in the dispersion method is preferably removed from the obtained dispersion as much as possible, but more preferably it is performed simultaneously with the classification operation.

  In the production method, it is also possible to provide a heating step after removing the organic solvent. By providing the heating step, the toner particle surface can be smoothed or the sphericity of the toner particle surface can be adjusted.

  In the classification operation, the fine particles can be removed in the liquid by a cyclone, a decanter, a centrifugal separator or the like. Of course, the classification operation may be performed after obtaining the powder after drying, but it is preferable in the liquid to perform the classification operation.

  Unnecessary fine particles or coarse particles obtained by the classification operation can be returned to the dissolving step and used for forming particles. At that time, fine particles or coarse particles may be wet.

  In the present invention, the peak molecular weight in gel permeation chromatography (GPC) of the soluble portion of tetrahydrofuran (THF) in the toner in the toner is 3000 to 15,000, the number average molecular weight is 1,000 to 10,000, and the weight average molecular weight is 8,000 to 50,000. It is preferable to maintain good developability.

  The toner of the present invention preferably has a weight average particle diameter (D4) of 2.5 to 10.0 μm, preferably 5.0 to 8.0 μm. Further, the ratio of 4 μm or less on the number basis is preferably 18.8% by number or less.

  The following are mentioned as a coloring agent used for this invention.

  Examples of the colorant for yellow include compounds typified by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds.

  Specific examples include the following.

  C. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 128, 129, 138, 147, 150, 151, 154, 155, 168, 180, 185, 213, 214. These can be used alone or in combination of two or more.

  Examples of the colorant for magenta include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds.

  Specific examples include the following.

  C. I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 146, 150, 166, 169, 177, 184, 185, 202, 206, 220, 221, 238, 254, 269, C.I. I. Pigment Bio Red 19. These can be used alone or in combination of two or more.

  Examples of the colorant for cyan include copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, and basic dye lake compounds.

  Specific examples include the following.

  C. I. Pigment blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66. These can be used alone or in combination of two or more.

  Examples of black colorants include the following. Furnace black, channel black, acetylene black, thermal black, lamp black carbon black. Further, metal oxides such as magnetite and ferrite are also used.

  In the present invention, when a dye or pigment having extremely high solubility in water is used as a colorant, it may be dissolved in water during the production process, and granulation may be disturbed or a desired color may not be obtained. .

  In the present invention, when used as a colorant for a normal color toner, the content of the colorant is preferably 2.0% by mass or more and 15.0% by mass or less based on the toner. When it is less than 2.0% by mass, the coloring power is lowered. On the other hand, when it is more than 15.0% by mass, the color space tends to be small. More preferably, it is 2.5 mass% or more and 12.0 mass% or less. Further, a light color toner having a reduced density can be preferably used in combination with a normal color toner. In this case, the content of the colorant is preferably 0.5% by mass or more and 5.0% by mass or less with respect to the toner. More preferably, it is 0.7 mass% or more and 3.0 mass% or less.

  The colorant preferably has a number average particle diameter of 200 nm or less in an image of the toner particles obtained by taking an enlarged photograph of the cross section of the toner particles. More preferably, it is 150 nm or less. On the other hand, the number average particle diameter is preferably 50 nm or more. When it exceeds 200 nm, the particle size is large and the shell of the colorant is difficult to form. Therefore, it tends to cause a reduction in coloring power and a color gamut.

  Examples of the wax used in the present invention include the following. Examples of the wax used in the present invention include natural waxes such as plant waxes (candelilla wax, carnauba wax, rice wax, etc.), animal waxes (beeswax, lanolin, etc.), mineral waxes (montane wax, ozokerite, Ceresin, etc.) and petroleum waxes (paraffin wax, microcrystalline wax, petrolactam, etc.). In terms of synthetic waxes, synthetic hydrocarbons (Fischer-Tropsch wax, polyethylene wax, polypropylene wax, etc.), modified waxes (montan wax derivatives, paraffin wax derivatives, microcrystalline wax derivatives, etc.), hydrogenated wax (hardened castor oil, hardened castor oil) Derivatives), fatty acids, ester waxes, ketone waxes and the like. In some cases, it may be purified.

  The wax is used in an amount of 1 to 40 parts by weight, more preferably 3 to 20 parts by weight, and particularly preferably 3 to 15 parts by weight with respect to 100 parts by weight of the binder resin.

  The wax used in the present invention preferably has a wax endothermic peak temperature of 50 to 100 ° C. in differential scanning calorimetry (DSC) measurement. More preferably, it is 65 ° C to 85 ° C. When the DSC peak is less than 50 ° C., the toner is likely to deteriorate due to the plasticizing effect of the wax as compared with the appropriate range, and the toner is likely to deteriorate during the heat cycle under high temperature and high humidity. is there. Further, when the DSC peak exceeds 100 ° C., it is difficult to finely disperse in the binder resin as compared with the appropriate range, and accordingly, the chargeability becomes non-uniform, and the developability and the fog tend to be deteriorated.

  The toner of the present invention may be used in combination with a charge control agent. The following substances are used for controlling the toner to be negatively charged. Although an example is given, things other than these may be used.

  For example, organometallic compounds and chelate compounds are effective, and there are monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic acids, and dicarboxylic acid-based metal compounds. Other examples include aromatic oxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

  Furthermore, urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, boron compounds, quaternary ammonium salts, calixarene, and the like can be mentioned.

  Particularly preferably, oxycarboxylic acid is used.

  The following substances are used to control the toner to be positively charged. An example is given, but other examples may be used.

  Modified products of nigrosine, such as nigrosine and fatty acid metal salts, guanidine compounds, imidazole compounds, quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate; analogs thereof Onium salts such as phosphonium salts and lake pigments thereof; triphenylmethane dyes and lake pigments thereof (as rake agents include phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, Gallic acid, ferricyanide, ferrocyanide, etc.); metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; Over DOO, dioctyl tin borate, diorgano tin borate such as dicyclohexyl tin borate, and the like. These can be used alone or in combination of two or more.

  The charge control agent is used in an amount of 0.01 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, per 100 parts by mass of the binder resin.

  In addition to the hydrophobic inorganic fine particles, additives may be externally added to the toner particles of the present invention as necessary.

  For example, charging aids, conductivity-imparting agents, fluidity-imparting agents, anti-caking agents, release agents at the time of heat roll fixing, resin fine particles or inorganic fine particles functioning as lubricants or abrasives can be mentioned.

  The resin fine particles preferably have an average particle size of 0.03 μm or more and 1.00 μm or less. Examples of the polymerizable monomer constituting the resin fine particles include the following. Styrene; o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene derivatives; acrylic acid; methacrylic acid; methyl acrylate, ethyl acrylate, n-butyl acrylate, acrylic acid Acrylic esters such as isobutyl, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate; methyl methacrylate, ethyl methacrylate , N-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, methacryl Dimethylaminoethyl, such as methacrylic acid esters of diethylaminoethyl methacrylate; acrylonitrile, methacrylonitrile, monomers acrylamide.

  Examples of the polymerization method for producing resin fine particles from the polymerizable monomer include suspension polymerization, emulsion polymerization, and soap-free polymerization. More preferably, particles obtained by soap-free polymerization are good.

  Examples of other fine particles include the following. Lubricants such as poly (ethylene fluoride), zinc stearate and polyvinylidene fluoride (especially preferred is polyvinylidene fluoride); abrasives such as cerium oxide, silicon carbide and strontium titanate (especially preferred is strontium titanate); titanium oxide A fluidity-imparting agent such as aluminum oxide (in particular, a hydrophobic agent is preferred); an anti-caking agent; a conductivity-imparting agent such as carbon black, zinc oxide, antimony oxide, and tin oxide. Further, a small amount of white fine particles and black fine particles having a polarity opposite to that of the toner may be used as a developability improver.

  As a developing method used for the toner of the present invention, a two-component development in which a toner mixed with a magnetic carrier is used as a developer, and the developer is transported by a magnetic force and developed.

  As the carrier for use in the two-component developer, any conventionally known carrier can be used. Specifically, particles having an average particle diameter of 20 μm or more and 300 μm or less, such as surface oxidized or unoxidized metal such as iron, nickel, cobalt, manganese, chromium, rare earth and alloys or oxides thereof 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 measurement of various physical properties according to the present invention will be described below.

<Measurement method of silicone oil immobilization rate>
(Extraction of free silicone oil)
1. Place 0.5 g of hydrophobic 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 1100 ° C. under an oxygen stream, the amount of generated CO and CO ₂ is measured by IR absorbance, and the amount of carbon in the sample is measured. The carbon amount before and after extraction of the silicone oil is compared to calculate the immobilization rate based on the carbon amount of the silicone oil.
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 the immobilization rate based on the carbon content of silicone oil.

<Method of measuring wettability of toner with methanol / water mixed solvent>
The wettability of the toner, that is, the hydrophobic property, is measured using a methanol dropping transmittance curve. Specifically, as the measuring device, for example, a powder wettability tester WET-100P manufactured by Reska Co., Ltd. is used, and a methanol dropping transmittance curve measured under the following conditions and procedures is used. First, in order to measure the hydrophobic characteristics of a toner, 70 ml of a hydrated methanol solution composed of 30% by volume of methanol and 70% by volume of water is placed in a container, and 0.5 g of a toner as a specimen is precisely weighed and added thereto. Prepare a sample solution. Next, transmittance was measured with light having a wavelength of 780 nm while continuously adding methanol to the measurement sample solution at a dropping rate of 1.3 ml / min, and the methanol dropping transmittance as shown in FIG. Create a curve. The methanol drop transmittance curve in FIG. 1 is the result of toner 1 used in the examples.

<Method of measuring wettability of hydrophobic inorganic fine particles in methanol / water mixed solvent>
In a 500 ml beaker, 0.20 g of hydrophobic inorganic fine particles are accurately weighed. Subsequently, 50 ml of pure water was added, and while stirring with a magnetic stirrer, methanol was continuously added at a dropping rate of 4.0 ml / min under the condition that the hydrophobic inorganic fine particles floated on the liquid surface. To do. 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 used is X, and the degree of hydrophobicity (M.W.) is determined according to the following formula.
Degree of hydrophobicity W. (%) = 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.

<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.

<Measuring method of molecular weight (peak molecular weight, number average molecular weight, weight average molecular weight) of toner particles>
The molecular weight distribution (peak molecular weight, number average molecular weight, weight average molecular weight) of the THF soluble content of the toner particles is measured by gel permeation chromatography (GPC) as follows. First, toner particles are dissolved in tetrahydrofuran (THF) at room temperature over 24 hours. The obtained solution is filtered through a solvent-resistant membrane filter “Maescho Disc” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is about 0.8% by mass. Using this sample solution, measurement is performed under the following conditions.
Apparatus: HLC8120 GPC (detector: RI) (manufactured by Tosoh Corporation)
Column: Seven series of Shodex KF-801, 802, 803, 804, 805, 806, 807 (manufactured by Showa Denko KK)
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 ml / min
Oven temperature: 40.0 ° C
Sample injection volume: 0.10 ml

  In calculating the molecular weight of the sample, standard polystyrene resin (for example, trade name “TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F— 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation) are used.

<Measurement method of glass transition temperature of toner particles>
The peak temperature of the maximum endothermic peak of the toner particles is measured according to ASTM D3418-82 using a differential scanning calorimeter “Q1000” (manufactured by TA Instruments).

  The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium.

  Specifically, about 10 mg of toner particles are accurately weighed and placed in an aluminum pan, and an empty aluminum pan is used as a reference. Measure in min. In this temperature rising process, a specific heat change is obtained in the temperature range of 40 ° C to 100 ° C. At this time, the intersection of the intermediate point line of the baseline before and after the change in specific heat and the differential heat curve is defined as a glass transition temperature Tg.

<Measurement method of weight average particle diameter (D4)>
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. Note that 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 was 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 aqueous solution is put 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 rotations / second. 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 Nikki 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%. . The 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, the present invention will be described with reference to specific examples, but the present invention is not limited thereto.

  A method for producing the hydrophobic inorganic fine particles used in this example is shown below.

(Production example of hydrophobic inorganic fine particles 1)
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., and 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. 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 1 used in the present invention.

The hydrophobic inorganic fine particles 1 had a silicone oil (B) immobilization ratio of 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. Further, this hydrophobic inorganic fine particle 1 had a BET specific surface area of 110 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 1.

(Example of production of hydrophobic inorganic fine particles 2)
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 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 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. After completion, hydrophobic inorganic fine particles 2 used in the present invention were obtained.

The hydrophobic inorganic fine particles 2 had an immobilization ratio of silicone oil (B) of 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, the hydrophobic inorganic fine particles 2 had a BET specific surface area of 130 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 2.

(Production example of hydrophobic inorganic fine particles 3)
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 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 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. When finished, the hydrophobic inorganic fine particles 3 used in the present invention were obtained.

The immobilization rate of the silicone oil (B) of the hydrophobic inorganic fine particles 3 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 3 had a BET specific surface area of 240 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 3.

(Production example of hydrophobic inorganic fine particles 4)
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 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 81% by mass.

Furthermore, after stirring the inside of the reaction tank, 0.5 parts by mass of dimethylsilicone oil (viscosity = 200 mm ² / s) as a silicone oil (B) was sprayed on 100 parts by mass of the silica raw material, and stirred for 2 hours. The treatment was terminated to obtain hydrophobic inorganic fine particles 4 used in the present invention.

The hydrophobic inorganic fine particles 4 had a silicone oil (B) immobilization ratio of 67% 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, the hydrophobic inorganic fine particles 4 had a BET specific surface area of 240 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 4.

(Production example of hydrophobic inorganic fine particles 5)
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 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 5 used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles 5 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, the hydrophobic inorganic fine particles 5 had a BET specific surface area of 150 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 5.

(Production example of hydrophobic inorganic fine particles 6)
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 20 parts by mass of dimethyl silicone oil (viscosity = 100 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 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 6 used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles 6 of the silicone oil (A) was 60% 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 particles 6 had a BET specific surface area of 140 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 6.

(Production example of hydrophobic inorganic fine particles 7)
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 28 parts by mass of dimethyl silicone oil (viscosity = 100 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 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 7 used in the present invention.

The immobilization rate of the silicone oil (A) of the hydrophobic inorganic fine particles 7 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 7 had a BET specific surface area of 130 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 7.

(Production example of hydrophobic inorganic fine particles 8)
Untreated dry silica (average primary particle size = 7 nm, BET specific surface area 330 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. 35 parts by mass of dimethyl silicone oil (viscosity = 100 mm ² / s) was sprayed as silicone oil (A) on 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 8 used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles 8 of the silicone oil (A) was 40% 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 particles 8 had a BET specific surface area of 290 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 8.

(Production example of hydrophobic inorganic fine particles 9)
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 250 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 40 parts by mass of dimethyl silicone oil (viscosity = 100 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 9 used in the present invention.

The immobilization rate of the silicone oil (A) of the hydrophobic inorganic fine particles 9 was 38% 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, the hydrophobic inorganic fine particles 9 had a BET specific surface area of 320 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 9.

(Example of production of hydrophobic inorganic fine particles 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 250 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 40 parts by mass of dimethyl silicone oil (viscosity = 100 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 10 used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles 10 of the silicone oil (A) was 35% 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, the hydrophobic inorganic fine particle 10 had a BET specific surface area of 350 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 10.

(Production example of hydrophobic inorganic fine particles 11)
Untreated dry silica (average primary particle size = 14 nm, BET specific surface area 160 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, the reactor was sealed, and 30 parts by mass of hexamethyldisilazane was sprayed inside 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. Thereafter, 4 parts by mass of dimethyl silicone oil (viscosity = 100 mm ² / s) as a silicone oil (A) was sprayed on 100 parts by mass of the silica raw material, and stirring was continued for 2 hours to complete the reaction. 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 11 used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles 11 of the silicone oil (A) was 60% by mass. In the measurement of the degree of hydrophobicity, the methanol concentration was 80% by volume, and the entire amount of hydrophobic inorganic fine particles was suspended in the solution. Further, the hydrophobic inorganic fine particles 11 had a BET specific surface area of 95 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 11.

(Production example of hydrophobic inorganic fine particles 12)
Untreated dry silica (average primary particle size = 10 nm, BET specific surface area 240 m ² / g) was charged into an autoclave equipped with a stirrer, and heated to 180 ° 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 = 100 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 reaction. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove by-products from the hydrophobic silica to obtain hydrophobic inorganic fine particles 12 used in the present invention.

The immobilization ratio of the hydrophobic inorganic fine particles 12 of the silicone oil (A) was 76% by mass. In the measurement of the degree of hydrophobicity, the methanol concentration was 73% by volume, and the entire amount of hydrophobic inorganic fine particles was suspended in the solution. Further, the hydrophobic inorganic fine particles 12 had a BET specific surface area of 220 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 12.

(Production example of hydrophobic inorganic fine particles 13)
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 250 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 40 parts by mass of dimethyl silicone oil (viscosity = 100 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 15 parts by mass of dimethyldiethoxysilane were sprayed inside with respect to 100 parts by mass of the silica raw 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 is depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane, dimethyldiethoxysilane and by-products from the hydrophobic silica, and the hydrophobic inorganic fine particles 13 used in the present invention are removed. Obtained.

The immobilization rate of the silicone oil (A) of the hydrophobic inorganic fine particles 13 was 35% 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. Further, the hydrophobic inorganic fine particles 13 had a BET specific surface area of 360 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 13.

(Production example of hydrophobic inorganic fine particles 14)
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 250 ° C. in a fluidized state by stirring.

The inside of the reactor was replaced with nitrogen gas, and the reactor was sealed, and 40 parts by mass of dimethyl silicone oil (viscosity = 100 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 dimethyldiethoxysilane was sprayed inside with respect to 100 parts by mass of the silica base 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 dimethyldimethoxysilane and by-products from the hydrophobic silica to obtain hydrophobic inorganic fine particles 14 used in the present invention.

The immobilization rate of the silicone oil (A) of the hydrophobic inorganic fine particles 14 was 35% 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. Further, BET specific surface area of the hydrophobic inorganic fine particles 14 was 360 m ² / g. Table 1 shows the physical properties of the hydrophobic inorganic fine particles 14.

  The production method of the toner particles used in this example is shown below.

(Production Example 1 of Toner Particles)
<Preparation of aqueous phase>
The following was charged while introducing nitrogen into a reactor equipped with a stirrer and a thermometer.
・ 91 parts by mass of styrene 81 parts by weight of methacrylic acid 100 parts by mass of butyl acrylate 1 part by mass of ammonium persulfate 11 parts by mass of sodium salt of ethylene oxide non-permissible sulfate ester 752 parts by mass of water Heat the above to 75 ° C. The reaction was carried out for 5 hours. Thereafter, 30 parts of a 1% ammonium persulfate aqueous solution was added and aged at 75 ° C. for 5 hours to obtain a vinyl resin fine particle dispersion 1.

-Water 990 mass parts-Fine particle dispersion 1 80 mass parts-Sodium dodecyl phenyl ether disulfonate 48.5% aqueous solution 40 mass parts-Ethyl acetate 90 mass parts The above was stirred and mixed, and the water phase 1 was obtained.

<Preparation of binder resin based on polyester>
The following was put into a reaction vessel equipped with a cooling tube, a nitrogen introducing tube and a stirrer.
-Terephthalic acid 28 parts by mass-Fumaric acid 3 parts by mass-Bisphenol A-propylene oxide 2 mol adduct 40 parts by mass-Bisphenol A-propylene oxide 3 mol adduct 32 parts by mass-Dibutyltin oxide 2 parts by mass

  The mixture was reacted at 230 ° C. for 8 hours and further reacted under reduced pressure for 5 hours, then cooled to 150 ° C., 3 parts by mass of phthalic anhydride was added thereto and reacted for 2 hours. Thereafter, the mixture was cooled to 80 ° C. and reacted with 18 parts by mass of isophorone diisocyanate in ethyl acetate for 2 hours to obtain urethane group-containing polyester resin 1.

  26 parts by mass of the urethane group-containing polyester resin 1 and 1 part by mass of isophoronediamine were reacted at 50 ° C. for 2 hours to obtain a binder resin 1 mainly composed of a polyester containing a urea group.

<Preparation of pigment / wax dispersion 1>
-60 parts by mass of a binder resin 1 mainly composed of polyester-C.I. I. Paste pigment containing PB 15: 3 100 parts by mass * Paste pigment having a solid content of 40% by mass (remaining 60% by mass) obtained without removing water from the pigment slurry to some extent Is water)
* The pigment / resin ratio in the solid content is 80% by mass.
First, the above raw materials are charged into a kneader type mixer according to the above formulation, and the temperature is raised under no pressure while mixing. Upon reaching the maximum temperature (necessarily determined by the boiling point of the solvent in the paste. In this case, about 90 to 100 ° C.), it was confirmed that the pigment in the aqueous phase was distributed or transferred to the molten resin phase. Thereafter, the mixture is further melted and kneaded for 30 minutes to sufficiently transfer the pigment in the paste. Thereafter, the mixer was once stopped and the hot water was discharged. Then, the temperature was further raised to 130 ° C., and the mixture was melted and kneaded for about 30 minutes to disperse the pigment and distill off the water. After the completion of this step, the mixture was cooled and the kneaded product was taken out to obtain a master batch 1.

  In a container in which a stir bar and a thermometer are set, 378 parts by mass of binder resin 1 mainly composed of polyester, 50 parts by mass of ester wax (melting point: 82.9, acid value: 2.59), and 953 parts by mass of ethyl acetate. The temperature was raised to 50 ° C. with stirring and held there for 3 hours. Then, it cooled to 30 degreeC in 1 hour, 100 mass parts of master batch 1 and 500 mass parts of ethyl acetate were thrown into the container, and also after stirring for 1 hour, the raw material solution 1 was obtained.

  1300 parts by mass of this raw material solution 1 was transferred to another container, and a bead mill (Ultra Visco Mill: manufactured by Imex Co., Ltd.) was used. The pigment / wax dispersion 1 was obtained by dispersing the cyan pigment and wax under the conditions of% volume filling and 3 passes.

<Emulsification and desolvation process>
The vessel was charged with 1: 1100 parts by weight of an aqueous phase and stirred for 1 minute at 5000 rpm with CLEARMIX (MTechnic Co., Ltd.), 900 parts by weight of pigment / wax dispersion 1 and 5 parts by weight of triethylamine were added, and the number of revolutions was increased. The mixture was stirred at 12000 rpm for 5 minutes to obtain an emulsified slurry 1.

  Thereafter, a stirring blade was set in the container, and the temperature was raised to 40 ° C. while mixing at 600 rpm, and the solvent was removed over 4 hours to obtain dispersion slurry 1. Furthermore, the temperature of the particles was raised to 65 ° C. and stirred for 30 minutes to smooth the surface properties of the particles.

<Washing and drying process>
After the dispersion slurry 1 is dried under reduced pressure,
1) 300 parts by mass of ion-exchanged water was added to the filter cake, mixed with a stirring blade at 600 rpm for 10 minutes, and then filtered.
2) 300 parts by mass of 10% by mass of sodium hydroxide was added to the filter cake of 1), mixed with a stirring blade at 600 rpm for 10 minutes, and then filtered under reduced pressure.
3) 300 parts by mass of 10% by mass hydrochloric acid was added to the filter cake of 2), mixed with a stirring blade at 600 rpm for 10 minutes, and then filtered.
4) 300 parts by mass of ion-exchanged water was added to the filter cake of 3), mixed with a stirring blade at 600 rpm for 10 minutes, and then filtered twice to obtain filter cake 1.

  The filter cake 1 was dried with a dryer at 45 ° C. for 3 days, and sieved with a mesh opening of 75 μm to obtain toner particles 1. The peak molecular weight was 6400, the number average molecular weight was 3200, the weight average molecular weight was 28000, and the glass transition temperature was 53 ° C. The physical properties of the toner particles 1 are shown in Table 2.

(Toner particle production example 2)
In the toner particle production example 1, toner particles 2 were obtained in the same manner as in the toner particle production example 1 except that no reaction with isophoronediamine was performed in the preparation of the binder resin containing polyester as a main component. The molecular weight was 5200, the number average molecular weight was 2800, the weight average molecular weight was 25000, and the glass transition temperature was 51 ° C. Table 2 shows the physical properties of Toner Particles 2.

(Toner particle production example 3)
In the toner particle production example 2, toner particles 3 were obtained in the same manner as in the toner particle production example 2 except that the reaction with isophorone diisocyanate was not performed in the preparation of the binder resin containing polyester as a main component. The peak molecular weight was 4,600, the number average molecular weight was 2500, the weight average molecular weight was 19000, and the glass transition temperature was 50 ° C. Table 2 shows the physical properties of the toner particles 3.

(Toner particle production example 4)
Toner particles 4 were obtained in the same manner as in Toner Particle Production Example 1 except that the binder resin containing polyester as a main component was prepared as follows. The peak molecular weight was 4900, the number average molecular weight was 2200, the weight average molecular weight was 12000, and the glass transition temperature was 50 ° C. Table 2 shows the physical properties of the toner particles 4.

<Preparation of binder resin based on polyester>
The following was put into a reaction vessel equipped with a cooling tube, a nitrogen introducing tube and a stirrer.
-28 parts by mass of terephthalic acid-3 parts by mass of fumaric acid-45 parts by mass of adduct with 2 moles of bisphenol A-propylene oxide 27 parts by mass of adduct with 3 mols of bisphenol A-propylene oxide-2 parts by mass of dibutyltin oxide

  The mixture was reacted at 230 ° C. for 8 hours and further reacted under reduced pressure for 5 hours, then cooled to 150 ° C., 3 parts by mass of phthalic anhydride was added thereto and reacted for 2 hours.

  Thereafter, the mixture was cooled to 80 ° C. and reacted with 15 parts by mass of isophorone diisocyanate in ethyl acetate for 2 hours to obtain a urethane group-containing polyester resin 4.

  23 parts by mass of the urethane group-containing polyester resin 4 and 1 part by mass of isophoronediamine were reacted at 50 ° C. for 2 hours to obtain a binder resin 4 mainly composed of a polyester containing a urea group.

(Preparation of toners 1 to 18)
Table 3 shows combinations of toner particles and hydrophobic inorganic fine particles. In any case, the hydrophobic inorganic fine particles were added at 0.7% by mass with respect to 100 parts by mass of the toner particles, and externally added and mixed with a Henschel mixer to obtain each toner.

  Table 3 shows the methanol concentration, the weight average particle diameter (D4), and the fine powder amount of 4 μm or less when the transmittance of light having a wavelength of 780 nm is 50% in the wettability test of each toner with respect to the methanol / water mixed solvent. As an example, FIG. 1 shows a methanol drop transmittance curve of the wettability test of toner 1 with respect to a methanol / water mixed solvent.

[Examples 1 to 14, Comparative Examples 1 to 4]
Next, evaluation was performed using toners 1 to 18 prepared as described above. The process cartridge was filled with toner and subjected to the heat cycle test shown below, and then evaluated. As the evaluation machine, a non-magnetic one-component printer LBP-2030 (manufactured by Canon) was used. The evaluation results are shown in Table 4. The heat cycle test under high temperature and high humidity is as follows.
<1> Hold at 25 ° C for 1 hour <2> Increase temperature linearly to 50 ° C over 11 hours <3> Hold at 45 ° C for 1 hour <4> Reduce temperature linearly to 50 ° C over 11 hours

  A total of 20 cycles were performed, with <1> to <4> being one cycle. Humidity is constant at 95%.

(1) Image density In a mode in which the horizontal line pattern with a printing rate of 2% is set to 1 sheet / 1 job, the machine is temporarily stopped between jobs, and the next job starts. An image printing test was performed, and the image density on the first and first 2000 sheets was measured. The evaluation was performed under high temperature and high humidity (32.5 ° C., 85% RH), where the influence on the toner chargeability is more severe. Evaluation was started after aging for 24 hours at (32.5 ° C., 85% RH) after the heat cycle test.

(2) Sleeve fusing The sleeve surface after a total of 12,000 image forming tests performed in (1) was visually observed, and the degree of toner contamination was evaluated according to the following criteria. The evaluation is performed under high temperature and high humidity (32.5 ° C., 85% RH).
A: Contamination is not observed.
B: Minor contamination is observed.
C: Contamination is partially observed.
D: Significant contamination is observed.

  If it is B or more, there is no problem at all in actual use.

(3) Fading A mode in which the horizontal line pattern with a printing rate of 1.5% is set to 1 sheet / job, and the machine is temporarily stopped between jobs, and the next job starts. Perform a sheet image test. Subsequently, 10 halftone patterns with a printing rate of 25% were output, and the occurrence of fading was confirmed. The evaluation criteria for fading are shown below. The evaluation is performed under high temperature and high humidity (32.5 ° C., 85% RH), which is a disadvantageous condition for fading because the sheet member and the toner carrier are easily contaminated by the silicone oil and the fluidity of the toner is deteriorated. It was. Evaluation was started after aging for 24 hours at (32.5 ° C., 85% RH) after the heat cycle test.
A: No occurrence.
B: There is a slightly thin part only at the end.
C: There is a slightly thin part.
D: Obviously, the density decreases in a band shape.
E: It is completely stripped white.

  If it is C or more, there is no problem in practical use.

(4) Photoreceptor Fusion The surface of the sleeve after a total of 12,000 image forming tests carried out in (1) was visually observed, and the degree of toner contamination was evaluated according to the following criteria. The evaluation is a severe condition for the fusion of the photoconductor because the image printing test is performed under high temperature and high humidity (32.5 ° C., 85% RH). The toner fusion to the photoreceptor was visually evaluated for the occurrence of toner fusion on the photoreceptor surface and the effect on the printout image.
A: Not generated B: Toner fusion is slight but inconspicuous C: Toner fusion is large and image defects that are white spots in solid black images are conspicuous

  If it is B or more, there is no problem at all in actual use.

(5) Coverage In a mode in which the horizontal line pattern with a printing rate of 2% is set to 1 sheet / 1 job, the machine is temporarily stopped between jobs, and the next job starts. A take-out test was performed, and the fogging after the first and 12,000 sheets was measured.

The image quality of the fog was evaluated on the white background on the test chart. The fog was evaluated by calculating the fog density (%) from the difference between the whiteness of the white portion of the fixed image measured by a reflectometer (manufactured by Tokyo Denshoku) and the whiteness of the transfer material to evaluate the fog.
Unused paper reflectance-Image white area reflectance = Fog (%)

  The evaluation was performed at low temperature and low humidity (15 ° C., 10% RH), where the toner charge distribution tends to be broad and is assumed to be more severe with respect to fog. The evaluation was started after aging for 24 hours at (15 ° C., 10% RH) after the heat cycle test.

(6) White Moya Immediately after the heat cycle test, it moved to low temperature and low humidity (15 ° C., 10% RH), and the evaluation was started under the condition where condensation is likely to occur. In the evaluation, the occurrence of white haze was confirmed with a halftone pattern with a printing rate of 25% on the first sheet.
A: No occurrence.
B: One white haze occurs per sheet, but disappears when five sheets or less pass.
C: 2 to 5 white haze occurs per sheet, but disappears when 10 sheets or less pass.
D: 6 to 10 white haze occurs per sheet, but disappears when 30 sheets or less pass.
E: 11 or more white haze occurs per sheet and does not disappear even when 30 sheets are passed.

  If it is C or more, there is no problem in practical use.

Claims (7)

In a toner particle containing at least a binder resin, a colorant, and a wax, and a toner containing hydrophobic inorganic fine particles,
The toner particles are prepared by granulating a mixed solution in which a toner composition containing at least a binder resin mainly composed of a polyester resin, a colorant, and a wax is dissolved or dispersed in an organic solvent in an aqueous medium, Toner particles obtained by removing the organic solvent,
The hydrophobic inorganic fine particles are hydrophobic inorganic fine particles surface-treated with a silane compound and / or a silazane compound after surface treatment with silicone oil (A),
A toner having a methanol concentration of 40% by volume or more when the transmittance of light having a wavelength of 780 nm is 50% in a wettability test for the methanol / water mixed solvent of the toner.   The toner according to claim 1, wherein the binder resin contains a modified polyester having urethane and / or urea groups.   The methanol concentration of the hydrophobic inorganic fine particles when the whole amount of the hydrophobic inorganic fine particles is suspended in a solution in a wettability test for a methanol / water mixed solvent is 86% by volume or more. The toner according to 1 or 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 base material, and the immobilization rate of the silicone oil (A) is 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) is The toner according to claim 5, wherein the toner is 40% by mass or less.

Images