JP2005107427A - Toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner excellent in developing performance, transferability and fixability, nearly independent of the environment, and having good durability and stability by bringing out the potential of a toner including a release agent to the fullest extent. <P>SOLUTION: In the toner including at least a resin, a colorant, a release agent and inorganic fine particles, two or more titanium oxides are included as the inorganic fine particles, one of the titanium oxides has anatase type crystal form, the other has rutile type crystal form, one of the titanium oxides has a number average particle diameter Da of >20 to 60 nm, the other has a number average particle diameter Db of 40-100 nm, and Da<Db is satisfied. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a toner that can be used for electrostatic charge development in an image forming method such as electrophotography, electrostatic recording, and electrostatic printing, or image formation in a toner jet system, and does not use oil for preventing high temperature offset. Alternatively, the present invention relates to a toner that exhibits high definition, high quality, and high image quality even when using a fixing unit that uses less oil.

  In recent years, electrophotographic apparatuses have been required to have specifications such as small size, light weight, and low power consumption with simpler elements while achieving color, high definition, and high image quality.

  Thus, the demand for high definition and high image quality of electrophotography is increasing in the market, and attempts to achieve high image quality and full color are being made in this technical field. In full-color electrophotography, three or four color toners are superimposed to form an image. However, if the color toners of the respective colors are not developed and transferred in the same way, color reproduction may be inferior or color unevenness may occur. Will occur. However, these colorings are performed with pigments and dyes, and these have a great influence on development and transfer. Furthermore, for full-color images, fixing properties, color mixing properties, and offset resistance at the time of fixing are important, and a binder resin suitable for these performances is selected, but the effect on the developability and transferability of this binder resin. Is also big. One of the effects is the influence of temperature and humidity on the charge amount, and there is an urgent need to develop a color toner having a stable charge amount even in a wide range of environments.

  One means for solving such problems is a method of adding various external additives to the toner. In particular, for the purpose of improving various image characteristics such as resolution, density uniformity, and fog, external addition of various fine powders is widely performed to improve the chargeability and transferability of toner. ing.

  Such inorganic fine powders that are widely used include (i) inorganic fine powders surface-treated with silicone oil, silicone varnish, silane compound, or (ii) surface-treated titania and surface treatment with aminosilane Are preferably used (Patent Documents 1 to 16).

  Furthermore, (iii) what adds 2 types of inorganic fine powder is used preferably (patent documents 17-30).

  However, in these proposals, although the electrophotographic characteristics are certainly improved, the uniformity of hydrophobicity is insufficient, and sufficient triboelectric charge cannot be obtained due to high humidity or long-term standing, resulting in a decrease in image density. And fogging. Alternatively, the triboelectric charge amount may be excessive under low humidity, causing image density unevenness and fogging. The toner could not be sufficiently releasable from the drum, resulting in inadequate transferability, resulting in a decrease in transfer efficiency and loss of transfer. . Furthermore, when applied to full color toners, it was not particularly severely satisfactory.

  Patent Documents 31 and 32 propose toners externally added with titanium oxide having primary particle size peaks of 10 to 20 nm and 30 to 60 nm. However, since titanium oxide having a primary particle size of 10 to 20 nm is used, titanium oxide is embedded in the toner surface due to long-term use, and accordingly, adhesion and fusion to the drum surface are likely to occur. It is not preferable. In addition, there are points to be improved regarding the oil-less fixing property, fluidity, charging property, transferability, durability, and the like of the toner.

  Further, Patent Document 33 proposes a toner externally added with anatase type titanium oxide and rutile type titanium oxide. However, this is a proposal related to titanium oxide having a large particle diameter, and there is a point to be improved in terms of toner fluidity and chargeability and drum surface polishing. In addition, there were points to be improved regarding the formation of full-color images and the low-temperature fixability of full-color toners. Patent Documents 34 and 35 propose magnetic toners to which anatase type titanium oxide and rutile type titanium oxide are externally added. However, these are proposals relating to the toner for MICR, and there are points to be improved in terms of toner fluidity and chargeability and drum surface polishing. Further, full color image formation, low temperature fixability of full color toner and the like have not been considered.

  Patent Documents 36 to 39 and the like have proposed a toner containing titanium oxide obtained by hydrophobizing metatitanic acid.

  However, there are points to be improved with respect to improvement in chargeability, improvement in transferability, prevention of carrier contamination, oilless fixability, etc. in toner containing a release agent.

  Further, Patent Documents 40 to 44 and the like propose a method in which inorganic particles having a large particle diameter are used in combination as an external additive for toner. The addition of inorganic particles with a large particle size creates a so-called spacer effect, and the toner surface to which the inorganic fine powder adheres is in direct contact with the carrier, developer coating blade, developer supply roller, developer inner wall, stirring blade, other toner, etc. To reduce stress. As a result, the lifetime of the toner can be extended by suppressing the burying of the inorganic fine powder. However, there have been points to be improved with respect to improvement in chargeability, improvement in transferability, prevention of carrier contamination, and the like.

Japanese Patent Publication No.53-22447 Japanese Patent Publication No. 1-31442 JP 58-216252 A JP 59-201063 A JP-A-64-88554 Japanese Examined Patent Publication No. 3-39307 JP-A-4-204750 JP-A-4-214568 JP-A-4-340558 Japanese Patent Laid-Open No. 5-19528 JP-A-5-61224 JP-A-5-94037 Japanese Patent Laid-Open No. 5-119517 JP-A-5-139748 Japanese Patent Laid-Open No. 6-11886 Japanese Unexamined Patent Publication No. 6-11887 Japanese Patent Publication No. 2-27664 JP-A-60-238847 JP-A 61-188546 JP 61-188547 A JP-A-62-174772 Japanese Patent Laid-Open No. 2-151872 JP-A-2-222966 JP-A-2-291565 JP-A-4-204751 JP-A-4-280255 JP-A-4-345168 JP-A-4-345169 JP-A-4-348354 JP-A-5-113688 Japanese Patent No. 3038912 Patent No. 3038913 JP 2002-318464 A JP 2002-318468 A JP 2002-318469 A JP-A-8-269359 Japanese Patent Laid-Open No. 9-304691 Japanese Patent Laid-Open No. 9-304692 JP-A-10-207117 JP-A-4-204751 JP-A-5-346682 JP-A-6-313980 JP-A-6-332235 JP-A-7-92724

  An object of the present invention is to provide a toner that solves the above-described problems.

  The object of the present invention is to provide a toner having excellent durability and stability, which maximizes the potential of the toner having a release agent, is excellent in developability, transferability and fixability, is hardly affected by the environment. There is to do.

  An object of the present invention is to provide a toner capable of forming a clear image without fogging, having high image density, excellent fine line reproducibility, highlight portion gradation, and excellent durability stability. .

  An object of the present invention is to provide a toner having excellent fluidity and excellent resolution and transferability.

  An object of the present invention is to provide a toner capable of polishing, removing or suppressing the generation of deposits on the surface of a photoconductor generated by long-term use and obtaining a stable image without image defects over a long period of time. It is to provide.

  A further object of the present invention is to provide a toner that is less affected by the environment such as temperature and humidity and has stable triboelectric charging characteristics.

  An object of the present invention is to provide a color toner suitable for forming a full-color image or a multi-color image.

  An object of the present invention is to provide a color toner having good transparency with OHP, excellent low-temperature fixability, and high-temperature offset resistance.

  An object of the present invention is to provide a color toner excellent in storage stability, heat resistance, and blocking resistance.

The present invention relates to a toner having at least a resin, a colorant, a release agent, and inorganic fine particles.
At least two or more kinds of titanium oxides are used as the inorganic fine particles, and the crystal form of the titanium oxide is one of anatase form and the other is rutile form, and the number average particle diameter of the titanium oxide is Da. The present invention relates to a toner characterized in that it is more than 20 nm and 60 nm or less, and the other is Db: 40 nm or more and 100 nm or less, and Da <Db.

  The present inventors achieve excellent low-temperature fixability, color mixing properties, and high-temperature offset resistance even in a fixing means that does not use oil for preventing high-temperature offset or uses less oil. In order to obtain a toner that achieves excellent developability, transferability, fixability, and durability in all environments, and further achieves long-term storage stability in a high-temperature environment, intensive studies were conducted. In particular, a toner having a release agent has a considerable amount of release agent components adhering to, contaminating, and adversely affecting the developer constituting material and the image forming system, so that it is difficult to make effective use of the toner characteristics. It was. As a result, it has been found that a toner having at least a binder resin, a colorant, a release agent, and at least two types of titanium oxide having the above particle diameter is extremely effective.

  Even in fixing means that does not use oil to prevent offset or uses less oil, it achieves excellent low-temperature fixability, color mixing properties, and high-temperature offset resistance, and is excellent in all environments A toner that achieves developability, transferability, fixability, and durability could be obtained.

  The toner of the present invention is characterized by having two types of titanium oxides having different particle sizes. One of the number average particle diameters is Da: more than 20 nm and 60 nm or less, and the other is Db: 40 nm or more and 100 nm or less, and Da <Db. More preferably, Da: 30 nm to 50 nm, and Db: 50 nm to 80 nm. Number average particle size Da: Titanium oxide having a particle size greater than 20 nm but not greater than 60 nm can impart optimum fluidity to a toner containing a release agent, and further, without causing a large scratch on the drum surface in development and cleaning processes. It is preferable because it can be polished. However, when Da is 20 nm or less, particularly in a toner containing a release agent, the toner is easily embedded in the surface of the toner particle, so that toner deterioration is likely to occur at an early stage, and the chargeability due to contact with the charging member becomes insufficient. In addition, toner scattering becomes a problem and the drum surface is not sufficiently polished. However, when Da is larger than 60 nm, the fluidity imparting ability is insufficient. Therefore, particularly in a toner containing a release agent, the release agent component adheres to and contaminates the developer constituting material and the image forming system. This is not preferable because it adversely affects the deterioration of charging characteristics and the occurrence of toner scattering.

  On the other hand, titanium oxide having a number average particle diameter Db of 40 nm or more and 100 nm or less suppresses contact with image forming apparatus members such as a carrier, a drum, and a sleeve, particularly in a toner containing a release agent, and is influenced by mechanical impact. This is preferable because contamination of the carrier and members is suppressed. When Db is smaller than 40 nm, particularly in a toner containing a release agent, it is easy to embed or adhere to the surface of the toner particles, so that an appropriate gap between the toner and the charging member or the drum cannot be created. For this reason, the toner is deteriorated, and the release agent component adheres to and contaminates the developer constituting material and the image forming system, and transferability, durability stability, and chargeability are reduced.

  When Db is larger than 100 nm, it is easy to release from the toner, and therefore it is not preferable because an appropriate gap between the charging member and the drum cannot be created. Further, the liberated titanium oxide remains in the developing machine in a large amount or adheres to various devices in the main body of the image forming apparatus, which is not preferable.

  As a result of intensive studies, the present inventors have added at least these two types of titanium oxide to the toner particles as the inorganic fine particles in the toner having at least a resin, a colorant, a release agent, and inorganic fine particles. The inventors have found that each titanium oxide functions extremely effectively and can maximize the potential of the toner.

  In the present invention, one of the two types of crystal forms of titanium oxide is that one is anatase and the other is rutile.

  Furthermore, in the present invention, one of the two types of titanium oxide has a crystal form in the course of crystal growth to anatase form or anatase form, and the number average particle diameter is Da: more than 20 nm and not more than 60 nm, and the other is a crystal Preferably, the shape is rutile and the number average particle diameter is Db: 40 nm or more and 100 nm or less.

  In the present invention, titanium oxide is used as the inorganic fine particles because it has characteristic charging characteristics. Titanium oxide exhibits a weak positive chargeability when not treated. Therefore, it is relatively easy to control the surface from weak negative to weak positive by treating the surface. This charging characteristic is an indispensable element in order to bring out the characteristics of the toner having a release agent, and is one of the characteristic characteristics that cannot be obtained with conventionally known materials such as silica. It is.

  In the present invention, among the two types of titanium oxide, the titanium oxide having a number average particle diameter of Da: more than 20 nm and not more than 60 nm is preferably anatase or titanium oxide in the course of crystal growth to anatase. Rutile titanium oxide is not preferable because its particle shape has an influence or it is difficult to impart sufficient fluidity to a toner having originally low fluidity including a release agent.

  In the present invention, the crystal form of titanium oxide having a number average particle diameter of Da: more than 20 nm and not more than 60 nm is in the course of crystal growth to the anatase form, so that more uniform and good fluidity can be obtained. It is preferable in that it is sharp and has good chargeability, has high reactivity with the treatment agent, and tends to be easily removed and adsorbed by the toner and the release agent adhering to the drum surface. The fact that the crystal is growing into the anatase form can be clarified by X-ray diffraction. In general, titanium oxide is known to have several peaks in X-ray diffraction. It is known that there is a characteristic and large peak around 2θ = 25.3 when the crystal system is anatase type, and around 2θ = 27.5 when the crystal system is rutile type. When the crystal form of titanium oxide is in the process of crystal growth to the anatase form, the intensity ratio (Ia / Ib) of the intensity Ia at 2θ = 25.3 and the minimum intensity Ib at 2θ = 20 to 30 deg in X-ray diffraction. ) Is 5.0 ≦ Ia / Ib ≦ 12.0.

  Furthermore, in the present invention, among the two types of titanium oxide, rutile titanium oxide is preferable as the titanium oxide having a number average particle diameter of Db: 40 nm to 100 nm. The rutile type has a higher Mohs hardness than the anatase type, so it is preferable for obtaining an appropriate gap between the toner and the charge imparting member and the drum. Therefore, it is preferable.

  Although the raw material and manufacturing method of the titanium oxide of this invention are not restrict | limited in particular, a manufacturing example is shown below.

  Slurry metatitanic acid is produced by hydrolyzing a dispersion obtained by using ilmenite as a starting material and decomposing it with sulfuric acid. After adjusting the pH of this metatitanic acid slurry, it is filtered, fired and crushed to obtain titanium oxide. While dispersing the obtained titanium oxide in the solution, a hydrophobizing agent is added dropwise and reacted. By subjecting this to filtration, heat treatment, and crushing treatment, rutile or anatase titanium oxide can be obtained.

  In addition, in order to obtain titanium oxide fine particles with less aggregates and uniform particle size distribution in a dispersion obtained by decomposing this with ilmenite as a starting material and sulfuric acid, titania sol having anatase type crystal structure is used. After adding as a seed, it hydrolyzes to produce slurry metatitanic acid. After adjusting the pH of the slurry of metatitanic acid, the slurry is sufficiently stirred so that coalescence of metatitanic acid particles does not occur in the slurry, and a hydrophobizing agent is added dropwise and reacted while being dispersed in the solution. This is filtered, dried, and pulverized to produce fine titanium oxide particles that are in the process of crystal growth into anatase form.

  Furthermore, as one method for producing titanium oxide, it is also known to obtain titanium oxide particles in which anatase type and rutile type are mixed in the particles by high-temperature firing of a titanium halogen compound in a gas phase. However, since the titanium oxide obtained in this way is influenced by the production method and high-temperature firing, and particle growth proceeds, the BET specific surface area is low, the particle size is large, and the particle size distribution is wide. In contrast, sufficient fluidity, transferability, abrasiveness, etc. cannot be imparted. Therefore, it can be said that it is not preferable for extracting the potential of the toner containing the release agent as in the present invention.

  As the surface treatment agent for titanium oxide of the present invention, known silane coupling agents, fluorine-containing silane coupling agents, titanate coupling agents, aluminum coupling agents, zircoaluminate coupling agents, and silane compounds Silicone oil, silicone varnish, etc. can be used.

  For example, alkyl alkoxysilanes such as dimethyldimethoxysilane, trimethylethoxysilane, butyltrimethoxysilane, dimethyldichlorosilane, trimethylchlorosilane, allyldimethylchlorosilane, hexamethyldisilazane, allylphenyldichlorosilane, benzyldimethyl Chlorosilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, divinylchlorosilane, dimethylvinylchlorosilane, trifluoropropyltrimethoxysilane, trifluoropropylmethyldimethoxysilane, trifluoropropylmethyldi A silane coupling agent such as chlorosilane can be used.

  As the surface treatment agent for titanium oxide having a number average particle diameter of more than 20 nm and not more than 60 nm of the present invention, it is particularly preferable to treat with alkylalkoxysilane in terms of obtaining good fluidity, chargeability and transferability.

  As the surface treatment agent for titanium oxide having a number average particle size of 40 nm to 100 nm of the present invention, it is particularly preferable to treat alkylalkoxysilane and fluorine-containing silane compound in combination for good chargeability and hydrophobicity, and carrier. Further, it is preferable in that high transferability can be obtained due to contribution of releasability from the drum surface, chargeability near the toner surface and releasability.

  In order to prevent the aggregation of particles and maximize the properties of the treatment agent, the addition amount of the treatment agent is about 100 parts by mass of inorganic fine particles to be added for titanium oxide having a number average particle size of more than 20 nm and 60 nm or less. The amount is preferably 1 to 60 parts by mass, more preferably 10 to 50 parts by mass. The titanium oxide having a number average particle size of 40 nm to 100 nm is preferably 1 to 20 parts by mass, more preferably 3 to 15 parts by mass with respect to 100 parts by mass of the inorganic fine particles to be added.

  In the present invention, surface treatment of titanium oxide particles includes methods such as a wet method and a dry method, but the present invention is not particularly limited to these methods.

BET specific surface area of the number average particle size 20nm ultra 60nm or less of the titanium oxide used in the present invention is preferably 80~300m ² / g, more preferably 140~250m ² / g.

When the BET specific surface area of titanium oxide is larger than 300 m ² / g, the amount of moisture adsorbed on the titanium oxide increases, and particularly in a toner having a release agent, it adversely affects the charging characteristics, and in a high humidity environment. This is not preferable because the frictional charge amount of the toner is remarkably reduced, toner scattering, fogging, and image density fluctuation are increased, and image quality is likely to deteriorate. In addition, when the BET specific surface area of titanium oxide is less than 80 m ² / g, the fluidity imparting ability is insufficient. Therefore, particularly in a toner containing a release agent, the release agent component is a developer constituent material or This is not preferable because it adheres to and contaminates the image forming system and has adverse effects such as deterioration of charging characteristics and accompanying toner scattering.

On the other hand, BET specific surface area of the number average particle size 40nm or 100nm or less of the titanium oxide used in the present invention is preferably ^{10~50m 2 / g, 20~40m 2 /} g is more preferable. When the BET specific surface area of the present titanium oxide is smaller than 10 m ² / g, it indicates that the particle size is large and that aggregates or coarse particles are present. This is not preferable because it tends to cause problems such as deterioration in properties, damage to the surface of the photoconductor, and deformation or damage to the cleaning means such as a cleaning blade, which manifests itself as image defects. Further, if the particle size of titanium oxide is large, it is easy to be released from the toner particles, and a large amount of the released titanium oxide remains in the developing machine or adheres to various devices in the main body of the image forming apparatus. Absent. Further, when the BET specific surface area of the present titanium oxide is larger than 50 m ² / g, since the particle size is small, particularly in the toner containing a release agent, it is easily embedded or adhered to the toner particle surface. Can not create an appropriate gap between the toner and the charge imparting member or the drum, so that the toner deteriorates, the release agent component adheres to and contaminates the developer constituting material and the image forming system, transferability, durability stability, charging This is not preferable because of a decrease in property.

  In the present invention, it is preferable to add 0.05 to 3 parts by mass of titanium oxide having a number average particle diameter of more than 20 nm and 60 nm or less with respect to 100 parts by mass of the toner particles. When the addition amount is less than 0.05 parts by mass, the fluidity and charging property improving effect and the drum surface polishing effect are small. On the other hand, when the addition amount exceeds 3 parts by mass, the fluidity of the toner becomes extremely high, so that uniform charging is inhibited.

  On the other hand, titanium oxide having a number average particle diameter of 40 nm to 100 nm is preferably added in an amount of 0.1 to 6 parts by mass with respect to 100 parts by mass of the toner particles. When the addition amount is less than 0.1 parts by mass, the effect of improving the chargeability and transferability is small. Further, when the addition amount exceeds 6 parts by mass, since the titanium oxide is excessively present, the fluidity of the toner is remarkably lowered, so that uniform charging is inhibited, or a large amount of excess titanium oxide is contained in the developing machine. It remains undesired or adheres to various devices in the main body of the image forming apparatus and adversely affects them.

  The addition ratio of titanium oxide having a number average particle size of more than 20 nm and not more than 60 nm and titanium oxide having a number average particle size of 40 nm to 100 nm is preferably 1: 2 to 1: 9. If the ratio of the addition amount of titanium oxide having a small particle size is increased, the fluidity becomes extremely high and the chargeability becomes nonuniform, which is not preferable. On the other hand, if the addition ratio of the titanium oxide having a large particle size is too high, the fluidity becomes extremely low, so that the charge amount becomes low and the chargeability becomes non-uniform.

  The toner of the present invention can have one or more kinds of inorganic fine particles in addition to the titanium oxide, if necessary. Known inorganic fine particles can be used. For example, silica fine particles, alumina fine particles, titanium oxide fine particles, zirconium oxide fine particles, magnesium oxide fine particles, metal oxide fine particles such as zinc oxide; nitrides such as boron nitride fine particles, aluminum nitride fine particles, carbon nitride fine particles; Examples thereof include calcium titanate, strontium titanate, barium titanate, and magnesium titanate. In particular, inorganic fine particles having an average primary particle diameter of 1 to 200 nm are preferably used, and inorganic fine particles having an average primary particle diameter of 20 to 100 nm are more preferably used. The inorganic fine particles are preferably subjected to a surface treatment in order to obtain necessary characteristics. In that case, as the surface treatment agent, the above-mentioned known ones can be used. As the inorganic fine particles used in the present invention, silica fine particles treated with a silane compound and oil are preferable in that good chargeability, transferability, and releasability from a carrier or a drum can be obtained. In particular, the combination of titanium oxide having a thickness of 40 to 100 nm according to the present invention produces a synergistic effect between the particle size characteristics of titanium oxide and the charging characteristics exhibiting weak positive to weak negative characteristics and the releasability of the oil-treated silica particles. It is preferable because extremely good toner transferability can be expressed.

  As the binder resin used in the toner particles of the present invention, various material resins conventionally known as binder resins for toner are used.

  For example, polystyrene, styrene-butadiene copolymer, styrene copolymer such as styrene-acrylic copolymer; ethylene copolymer such as polyethylene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer Phenolic resin, epoxy resin, acrylic phthalate resin, polyamide resin, polyester resin, maleic acid resin and the like. These resins may be used alone, or two or more kinds of resins may be mixed and used.

  Among these resins, (a) a polyester resin having a particularly high negative chargeability, (b) a hybrid resin having a polyester unit and a vinyl polymer unit, or (c) a mixture thereof may be used. preferable.

  In particular, when a hybrid resin is used, the effect of the present invention is increased. The hybrid resin, particularly when combined with a release agent, has good dispersibility of the release agent and can effectively function the release agent at the time of fixing. It also has good heat resistance and blocking resistance and is suitable for color toners. On the other hand, the negative chargeability is strong and the charge is likely to be excessive, and there is a tendency that an extreme increase in the charge amount and the accompanying developability and transferability are likely to decrease. However, when the titanium oxide of the present invention is combined, those problems are eliminated and excellent toner characteristics can be obtained.

  In the present invention, “polyester unit” refers to a portion derived from polyester, and “vinyl polymer unit” refers to a portion derived from a vinyl polymer. The polyester monomer constituting the polyester unit is a polyvalent carboxylic acid component and a polyhydric alcohol component, and the vinyl polymer unit is a monomer component having a vinyl group. A monomer having a vinyl group or a monomer having a polyhydric alcohol component and a vinyl group is defined as a “polyester unit” component.

  One feature of the toner of the present invention is that it contains one or more release agents.

  A well-known thing can be used as a mold release agent used for this invention. In the present invention, as the release agent particularly preferably used, an aliphatic hydrocarbon release agent may be mentioned. For example, a low molecular weight alkylene polymer obtained by radical polymerization of alkylene under high pressure or a Ziegler catalyst under low pressure; an alkylene polymer obtained by thermally decomposing a high molecular weight alkylene polymer; a synthesis gas containing carbon monoxide and hydrogen A synthetic hydrocarbon release agent obtained from the distillation residue of hydrocarbons obtained by the method or by hydrogenation of these is preferred. Furthermore, the thing which fractionated the hydrocarbon release agent by the use of the press perspiration method, the solvent method, vacuum distillation, or a fractional crystallization system is used more preferably. The hydrocarbon as a base is synthesized by the reaction of carbon monoxide and hydrogen using a metal oxide catalyst (mostly two or more multi-component systems) [for example, the Jintol method, the Hydrocol method (the fluidized catalyst bed Hydrocarbon compounds synthesized by use)]; hydrocarbons with up to about a few hundred carbon atoms obtained by the age method (using the identified catalyst bed) in which a large amount of release agent-like hydrocarbons are obtained; Hydrocarbons polymerized by a catalyst are preferred because they are linear hydrocarbons with little branching, small and long saturation. In particular, a release agent synthesized by a method that does not depend on polymerization of alkylene is preferable also from its molecular weight distribution.

  The molecular weight distribution of the release agent is preferably such that the main peak is in the region of molecular weight 400-2400, more preferably in the region of 430-2000. By giving such a molecular weight distribution, preferable thermal characteristics can be imparted to the toner.

  Further, the melting point of the release agent is preferably 60 to 100 ° C., and more preferably 65 to 90 ° C. in order to function more effectively at the time of fixing the toner. The endothermic peak temperature of the toner of the present invention is a temperature showing a maximum value at which the endothermic peak of the main peak of the endothermic curve is obtained in the differential scanning calorimeter (DSC) measurement of the toner containing the release agent. It is. This endothermic peak temperature is a physical property value derived from the melting point of the release agent.

  The release agent is used in an amount of 0.1 to 20 parts by mass, preferably 0.5 to 10 parts by mass, per 100 parts by mass of the binder resin.

  The method for adding the release agent is not particularly limited. Usually, the resin is added to the toner by a method of dissolving the resin in a solvent, raising the temperature of the resin solution, adding and mixing with stirring, or a method of mixing at the time of kneading.

  As the colorant of the present invention, known dyes and / or pigments are used.

  As a coloring pigment for magenta toner, C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 155, 163, 202, 206, 207.209; I. Pigment violet 19; C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35, etc. are mentioned.

  Although the pigment may be used alone, it is more preferable from the viewpoint of the image quality of the full color image to improve the sharpness by using the dye and the pigment together.

  Examples of the magenta toner dye include C.I. I solvent red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121; I. Disper thread 9; I. Solvent Violet 8, 13, 14, 21, 27; C.I. I. Oil-soluble dyes such as Disper Violet 1, C.I. I. B. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40; I. Basic violet 1,3,7,10,14,15,21,25,26,27,28 etc. are mentioned.

  Examples of the color pigment for cyan toner include C.I. I. Pigment blue 2, 3, 15, 16, 17; I. Bat Blue 6; C.I. I. Acid Blue 45 or a copper phthalocyanine pigment in which 1 to 5 phthalimidomethyl groups are substituted on a phthalocyanine skeleton having a structure represented by the following formula.

〔式中、ｎは１〜５の整数を示す。〕

[In formula, n shows the integer of 1-5. ]

  As a coloring pigment for yellow, C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 65, 73, 74, 83, 97, 155, 180; I. Examples include bat yellow 1, 3, 20 and the like.

  In addition, C.I. I. Direct Green 6, C.I. I. Basic Green 4, C.I. I. Dyes such as Basic Green 6 and Solvent Yellow 162 can also be used.

  As the black colorant used in the present invention, carbon black, a magnetic material, and a color toned in black using the yellow / magenta / cyan colorant shown above can be used.

  The amount of the colorant used is preferably 0.1 to 15 parts by mass, more preferably 0.5 to 12 parts by mass, and most preferably 2 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  As a method for producing the toner particles used in the present invention, the constituent materials are well kneaded by a heat kneader such as a hot roll, a kneader, and an extruder, then mechanically pulverized, and the pulverized powder is classified to obtain toner particles. A method of obtaining toner particles by dispersing a material such as a colorant in a binder resin solution and then spray-drying; a monomer obtained by mixing a predetermined material with a polymerizable monomer to constitute the binder resin; A toner production method by suspension polymerization in which a composition is obtained and toner particles are obtained by polymerizing an emulsified suspension of the composition can be applied.

  In the present invention, an organic metal compound can be contained in the toner. As the organometallic compound used in the present invention, a compound of an aromatic carboxylic acid and a divalent or higher metal is preferable.

  Examples of the aromatic carboxylic acid include the following three compounds.

〔式中、Ｒ₁乃至Ｒ₇は同一又は異なる基を示し、水素原子、炭素数１〜１２のアルキル基、炭素数２〜１２のアルケニル基、−ＯＨ，−ＮＨ₂，−ＮＨ（ＣＨ₃），−Ｎ（ＣＨ₃）₂，−ＯＣＨ₃，−Ｏ（Ｃ₂Ｈ₅），−ＣＯＯＨ又は−ＣＯＮＨ₂を示す。〕

[Wherein, R _{1 to} R ₇ represent the same or different groups, and are a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, —OH, —NH ₂ , —NH (CH ₃ ), —N (CH ₃ ) ₂ , —OCH ₃ , —O (C ₂ H ₅ ), —COOH or —CONH ₂ . ]

Preferable R ₁ includes a hydroxyl group, an amino group, and a methoxy group, and among them, a hydroxyl group is preferable. As the aromatic carboxylic acid, a dialkyl salicylic acid such as di-tert-butylsalicylic acid is particularly preferable.

The metal forming the organometallic compound is preferably a divalent or higher valent metal atom. Examples of the divalent metal include Mg ²⁺ , Ca ²⁺ , Sr ²⁺ , Pb ²⁺ , Fe ²⁺ , Co ²⁺ , Ni ²⁺ , Zn ²⁺ and Cu ²⁺ . As the divalent metal, Zn ²⁺ , Ca ²⁺ , Mg ²⁺ and Sr ²⁺ are preferable. Examples of the trivalent or higher metal include Al ³⁺ , Cr ³⁺ , Fe ³⁺ and Ni ³⁺ . Among these metals, Al ³⁺ , Fe ³⁺ , Cr ³⁺ and Zn ²⁺ are preferable, and Al ³⁺ is particularly preferable.

  In the present invention, the organometallic compound is preferably an aluminum compound of di-tert-butylsalicylic acid or a zinc compound of di-tert-butylsalicylic acid.

  The metal compound of the aromatic carboxylic acid is prepared by, for example, dissolving an aromatic carboxylic acid in an aqueous sodium hydroxide solution, dropping an aqueous solution in which a divalent or higher valent metal atom is melted into the aqueous sodium hydroxide solution, stirring with heating, After adjusting the pH of the aqueous solution, cooling to room temperature, and washing with filtered water, a metal compound of an aromatic carboxylic acid can be synthesized. However, it is not limited only to the above synthesis method.

  The organometallic compound is used in an amount of 0.1 to 10 parts by mass (more preferably 0.2 to 5 parts by mass) per 100 parts by mass of the binder resin in terms of adjusting the viscoelastic characteristics and triboelectric charging characteristics of the toner. preferable.

  In the toner of the present invention, a compound other than the above-described organometallic compound can be used as a charge control agent as necessary in order to further stabilize the chargeability. Examples of the charge control agent include nigrosine and imidazole compounds. The charge control agent is used in an amount of 0.1 to 10 parts by mass, preferably 0.1 to 7 parts by mass, per 100 parts by mass of the binder resin.

  In the present invention, when the toner is positively charged, it is preferable to add nigrosine, a triphenylmethane compound, a rhodamine dye, polyvinyl pyridine, or the like as a charge control agent exhibiting positive chargeability.

  When producing a color toner, it is preferable to use a colorless or light-colored positive charge control agent that does not affect the color tone of the toner.

  Next, the particle size of the toner used in the present invention will be described.

  As a result of intensive studies on image density, highlight reproducibility (halftone reproducibility), and fine line reproducibility, the toner of the present invention preferably has a weight average particle diameter of 3 to 9 μm.

  When the weight average particle size of the toner is larger than 9 μm, there are basically few toner particles that can contribute to high image quality, and it is difficult to faithfully adhere to the fine electrostatic charge image on the photosensitive drum, and highlight reproducibility is improved. Poor and low resolution. Too much toner on the electrostatic charge image is more than necessary, and the toner consumption tends to increase.

  On the other hand, when the weight average particle diameter of the toner is smaller than 3 μm, the charge amount per unit mass of the toner tends to be high, and the density is low, especially the image density is low under low temperature and low humidity. Particularly, it is not suitable for developing an image having a high image area ratio such as a graphic image.

  Further, when the weight average particle diameter of the toner is smaller than 3 μm, the specific surface area of the toner is increased, so that the amount of the release agent in the vicinity of the toner surface is extremely increased, and the contact charging with the carrier is not smoothly performed. Toner that cannot be sufficiently charged increases, scattering to non-image areas, and fog become conspicuous. In order to cope with this, it is conceivable to reduce the diameter of the carrier in order to increase the specific surface area of the carrier. However, in the case of a toner having a weight average diameter of less than 3 μm, toner self-aggregation easily occurs, and uniform mixing with the carrier can be achieved in a short time. In the continuous toner replenishment durability, fogging tends to occur.

  The toner of the present invention can be used in any development method of non-magnetic one-component toner development and two-component development.

  When the toner of the present invention is used for a two-component developer, examples of carriers used in combination include metals such as surface oxidized or unoxidized iron, nickel, copper, zinc, cobalt, manganese, chromium, rare earth, and the like. Alloys or oxides and ferrites can be used.

  In particular, a Mn—Mg—Fe three-element magnetic ferrite particle formed mainly of manganese, magnesium and iron components is preferable in that good charging characteristics can be obtained. The magnetic ferrite particles contain 0.001 to 1 part by mass (more preferably 0.005 to 0.5 parts by mass) of silicon element per 100 parts by mass of magnetic ferrite particles as a coating resin for magnetic ferrite particles. This is particularly preferable when a resin is used.

  The magnetic carrier particles are preferably coated with a resin, and the resin is preferably a silicone resin. In particular, the nitrogen-containing silicone resin or the modified silicone resin produced by the reaction of the nitrogen-containing silane coupling agent and the silicone resin is capable of imparting a negative triboelectric charge to the color toner of the present invention, environmental stability, carrier This is preferable in terms of suppression of surface contamination.

  The magnetic carrier preferably has an average particle diameter of 15 to 60 μm (more preferably 25 to 50 μm) in relation to the weight average particle diameter of the color toner.

  In order to obtain stable charging characteristics in any environment, it is preferable to coat the surface of the carrier particles with a resin.

  As a method for coating the surface of the carrier particles with a resin, a conventionally known method such as a method in which the resin is dissolved or suspended in a solvent and applied to the carrier particles, or a method of simply mixing with powder can be applied. .

  The substance fixed to the carrier particle surface varies depending on the toner, for example, polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin, polyester resin, styrene resin, acrylic resin, polyamide, polyvinyl butyral, It is appropriate to use amino acrylate resins alone or in plural.

  In particular, a silicone resin is preferable in terms of charge imparting property, toner spent resistance, and the like.

  In addition, by using an aminosilane coupling agent, particularly an aminosilane coupling agent in which the amino group is a tertiary amine, in the presence of an organic acid catalyst in the above resin as a substance fixed to the carrier particle surface, It is possible to obtain a stable resin-coated carrier that hardly deteriorates the developer characteristics over a long period of time while being raised.

  Examples of the aminosilane coupling agent preferably used in the present invention include N, N-dimethylaminotrimethoxysilane, N, N-diethylaminotrimethoxysilane and the like, and 0.1 to 10 parts by mass, preferably 100 parts by mass of silicone resin Is preferably 1 to 5 parts by mass.

  The coating resin is preferably 0.1 to 30 parts by mass (preferably 0.2 to 15 parts by mass) with respect to 100 parts by mass of the carrier.

  When a two-component developer is prepared by mixing with the toner in the present invention, the mixing ratio is 2 to 15% by mass, preferably 3 to 13% by mass, more preferably 4 to 10% as the toner concentration in the developer. Good results are usually obtained with mass%. When the toner concentration is less than 2% by mass, the image density tends to be low, and when a toner containing a release agent as in the present invention is used, the developer is likely to deteriorate, which is not preferable. When the amount exceeds 15% by mass, the toner charge amount distribution becomes wide and fog and in-machine scattering occur, which is not preferable.

  The measuring method of each physical property value used in the present invention will be described below.

-Method for Measuring Ia and Ib of Titanium Oxide of the Present Invention The X-ray diffraction measurement of the present invention is performed under the following conditions using CuKα rays and using the toner and titanium oxide as a sample.

Used measuring machine / Mach Science, full automatic X-ray diffractometer MXP18
X-ray tube / Cu
Tube voltage / 50KV
Tube current / 300mA
Scan method / 2θ / θ scan Scan speed / 4deg. / Min
Sampling interval / 0.020 deg.
Start angle (2θ) / 3deg.
Stop angle (2θ) / 60 deg.
Divergence slit / 0.5 deg.
Scattering slit / 0.5 deg.
Receiving slit / 0.3mm.
Uses curved monochromator

-Primary average particle diameter measuring method of titanium oxide and inorganic fine particles of the present invention The primary particle size is determined by observing the titanium oxide and inorganic fine particles of the present invention with a transmission electron microscope, measuring the long diameter of 100 particles, and the number average particle size. Find the diameter. The particle diameter on the toner particles is observed with a scanning electron microscope, and the major axis of 100 particles is measured to determine the number average particle diameter.

  The magnification at the time of measurement is 40,000 to 60,000 times, and targets particles of 0.5 nm or more.

-Method for measuring the BET specific surface area of titanium oxide and inorganic fine particles of the present invention The BET specific surface area of the titanium oxide and inorganic fine particles of the present invention is measured as follows.

  The BET specific surface area is obtained by a BET multipoint method using, for example, a fully automatic gas adsorption amount measuring apparatus (Autosoap 1) manufactured by Yuasa Ionics Co., Ltd., using nitrogen as the adsorption gas. As a sample pretreatment, deaeration is performed at 50 ° C. for 10 hours.

-Differential scanning calorimeter (DSC) measurement of toner of the present invention Measurement is performed according to ASTM D3418-82 using a differential scanning calorimeter (DSC measuring device) and DSC-7 (manufactured by Perkin Elmer).

  The measurement sample is precisely weighed in an amount of 2 to 10 mg, preferably 5 mg. This is put in an aluminum pan, and an empty aluminum pan is used as a reference, and measurement is performed at a temperature rise rate of 10 ° C./min at room temperature and normal humidity within a measurement temperature range of 30 to 200 ° C. In this temperature raising process, an endothermic peak of the main peak of the DSC curve in the temperature range of 30 to 200 ° C. is obtained. The endothermic peak temperature is a temperature showing a maximum value among them.

The toner particle size measuring method of the present invention uses Coulter Counter TA-II or Coulter Multisizer II (manufactured by Coulter Co.). As the electrolyte, first grade sodium chloride is used to prepare an approximately 1% NaCl aqueous solution. For example, ISOTON-II (manufactured by Coulter Scientific Japan) can be used. As a measuring method, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of the aqueous electrolytic solution, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the volume and number of toner particles are measured for each channel by using the 100 μm aperture as the aperture. Thus, the toner volume distribution and number distribution are calculated. Then, the weight-based toner weight average particle diameter (D4) obtained from the volume distribution of the toner particles (the median value of each channel is a representative value for each channel) is obtained.

  As channels, 2.00 to 2.52 μm; 2.52 to 3.17 μm; 3.17 to 4.00 μm; 4.00 to 5.04 μm; 5.04 to 6.35 μm; 6.35 to 8. 00 μm; 8.00 to 10.08 μm; 10.08 to 12.70 μm; 12.70 to 16.00 μm; 16.00 to 20.20 μm; 20.20 to 25.40 μm; 25.40 to 32.00 μm; 13 channels of 32.00-40.30 μm are used.

  Examples of production and examples relating to the present invention are shown below, but the present invention is not limited to these examples.

Titanium oxide production example (titanium oxide production example A-1)
Ilmenite ore containing 50% by mass of TiO ₂ equivalent was used as a starting material. The raw material was dried at 150 ° C. for 2 hours, and sulfuric acid was added and dissolved to obtain an aqueous TiOSO ₄ solution. This was concentrated, and after adding 4.5 parts by mass of a titania sol having anatase crystals as a seed, hydrolysis was performed at 125 ° C. to obtain a slurry of TiO (OH) ₂ containing impurities. This slurry was repeatedly washed with water at pH 5 to 6 to sufficiently remove sulfuric acid, FeSO ₄ , and impurities. Then, a slurry of high purity metatitanic acid [TiO (OH) ₂ ] was obtained. The average particle size at this time was 38 nm.

The pH of this metatitanic acid slurry was adjusted to 8-9, and metatitanic acid was sufficiently pulverized with a ball mill. Thereafter, the temperature of the slurry was adjusted to 30 ° C. and the pH to about 2 with sufficient stirring. Metatitanic acid was contained in the slurry in an amount of about 6% by mass. To 100 parts by mass of metatitanic acid in the slurry, 40 parts by mass of i-C ₄ H ₉ —Si— (OCH ₃ ) ₃ as a hydrophobizing agent is used as a solid component so that particles are not coalesced. The mixture was dropped and mixed while stirring sufficiently. Further, the pH of the slurry was adjusted to 6.5 with sufficient stirring.

This is filtered and dried, then heat treated at 140 ° C. for 2 hours to produce hydrophobic titanium oxide fine particles, and then repeatedly pulverized by a jet mill until there are no aggregates of hydrophobic titanium oxide fine particles. When 2θ = 25.3 deg, Ia = 0.71 Kcps, when 2θ = 30.2 deg, Ib = 0.10 Kcps, intensity ratio (Ia / Ib) = 10.9, BET specific surface area = 200 m ² / g, number average Titanium oxide A-1 having a particle size of 40 nm and a hydrophobization degree of 60% was obtained.

  Table 1 shows production examples of titanium oxide.

(Titanium oxide production example A-2)
Titanium oxide A− was prepared in the same manner as in Production Example 1 except that 3.0 parts by mass of titania sol having anatase crystals was added as a seed, hydrolysis was performed at 120 ° C., and 50 parts by mass of a hydrophobizing agent was added. 2 was obtained.

(Titanium oxide production example A-3)
Except for adding 6.0 parts by mass of a titania sol having anatase crystals as a seed, performing hydrolysis at 130 ° C., and adding 30 parts by mass of n-butyltrimethoxysilane as a hydrophobizing agent in a solid form, In the same manner as in Production Example 1, titanium oxide A-3 was obtained.

(Titanium oxide production example A-4)
Addition of 2.5 parts by mass of titania sol having anatase crystals as a seed, hydrolysis at 120 ° C., and i-C ₄ H ₉ —Si— (OCH ₃ ) ₃ as a hydrophobizing agent Titanium oxide A-4 was obtained in the same manner as in Production Example 1 except that mass parts were added.

(Titanium oxide production example A-5)
Ilmenite ore containing 50% by mass of TiO ₂ equivalent was used as a starting material. The raw material was dried at 150 ° C. for 2 hours, and sulfuric acid was added and dissolved to obtain an aqueous TiOSO ₄ solution. This was concentrated, and after adding 4.5 parts by mass of titania sol having anatase crystals as a seed, hydrolysis was performed at 125 ° C. to obtain a slurry of TiO (OH) ₂ containing impurities. This slurry was repeatedly washed with water at pH 5 to 6 to sufficiently remove sulfuric acid, FeSO ₄ , and impurities. Then, a slurry of high purity metatitanic acid [TiO (OH) ₂ ] was obtained. This slurry was filtered, baked at 170 ° C. for 2 hours, and then repeatedly pulverized by a jet mill until fine particle aggregates disappeared to obtain titanium oxide having an average particle diameter of 57 nm. This titanium oxide is dispersed in ethanol, and 30 parts by mass of n-propyltrimethoxysilane as a hydrophobizing agent as a hydrophobizing agent with respect to 100 parts by mass of titanium oxide is sufficient so that particles are not coalesced. While stirring, the mixture was dropped and reacted. Further, the pH of the slurry was adjusted to 6.5 with sufficient stirring.

  This is filtered and dried, then heat-treated at 170 ° C. for 2 hours to produce hydrophobic titanium oxide fine particles, and then subjected to repeated crushing treatment with a jet mill until the aggregates of the titanium oxide fine particles disappear. A-5 was obtained.

(Titanium oxide production example A-6)
Adding 1.5 parts by mass of a titania sol having anatase crystals as a seed, hydrolyzing at 115 ° C., and 50 as a hydrophobizing agent i-C ₄ H ₉ —Si— (OCH ₃ ) ₃ in solid form Titanium oxide A-6 was obtained in the same manner as in Production Example 1 except that mass parts were added.

(Titanium oxide production example A-7)
Filtration and baking of the slurry at 180 ° C. for 3 hours, addition of 30 parts by mass of i-C ₄ H ₉ —Si— (OCH ₃ ) ₃ as a hydrophobizing agent, heating at 170 ° C. for 3 hours Titanium oxide A-7 was obtained in the same manner as in Production Example 5 except for the treatment.

(Titanium oxide production example B-1)
Ilmenite ore containing 50% by mass of TiO ₂ equivalent was used as a starting material. The raw material was dried at 150 ° C. for 2 hours, and sulfuric acid was added and dissolved to obtain an aqueous TiOSO ₄ solution. This was concentrated, and after adding 4.5 parts by mass of a titania sol having rutile crystals as a seed, hydrolysis was performed at 125 ° C. to obtain a slurry of TiO (OH) ₂ containing impurities. This slurry was repeatedly washed with water at pH 5 to 6 to sufficiently remove sulfuric acid, FeSO ₄ , and impurities. Then, a slurry of high purity metatitanic acid [TiO (OH) ₂ ] was obtained. This slurry was filtered, baked at 180 ° C. for 2 hours, and then pulverized repeatedly by a jet mill until no aggregates of fine particles disappeared, and titanium oxide having an average particle diameter of 32 nm was obtained. This titanium oxide is dispersed in ethanol, and 7 parts by mass of i-butyltrimethoxysilane as a hydrophobizing agent and 7 parts by mass of trifluoropropyltrimethoxysilane as a hydrophobizing agent with respect to 100 parts by mass of titanium oxide. The mixture was dropped and mixed with sufficient stirring so that coalescence of mass parts and particles did not occur, and reacted. Further, the pH of the slurry was adjusted to 6.5 with sufficient stirring.

  This was filtered and dried, then heat-treated at 170 ° C. for 2 hours, and then repeatedly pulverized by a jet mill until titanium oxide aggregates disappeared to obtain titanium oxide B-1.

(Titanium oxide production example B-2)
Hydrolysis was performed at 120 ° C. to obtain a slurry of impurities containing TiO (OH) ₂ , and after baking at 170 ° C. for 2 hours, trifluoropropyltrimethoxysilane was used instead of trifluoropropyltrimethoxysilane as a hydrophobizing agent. Titanium oxide B-2 was obtained in the same manner as in Production Example B-1, except that propylmethyldimethoxysilane was used.

(Titanium oxide production example B-3)
Hydrolysis was performed at 140 ° C. to obtain a slurry of impurities containing TiO (OH) ₂ , and after baking at 190 ° C. for 2 hours, i-butyltrimethoxysilane was used as a hydrophobizing agent in a solid form. Titanium oxide B-3 was obtained in the same manner as in Production Example B-1, except that 5 parts by mass and 5 parts by mass of trifluoropropylmethyldichlorosilane in solid form were used.

(Titanium oxide production example B-4)
Titanium oxide B-4 was obtained in the same manner as in Production Example B-1, except that hydrolysis was performed at 120 ° C. and 10 parts by mass of i-butyltrimethoxysilane as a hydrophobizing agent was used as a solid component. It was.

(Titanium oxide production example B-5)
Titanium oxide B-5 was obtained in the same manner as in Production Example B-1, except that hydrolysis was performed at 155 ° C. and 6 parts by mass of trifluoropropyltrimethoxysilane as a hydrophobizing agent was used as a solid component. It was.

(Titanium oxide production example B-6)
Titanium oxide B-6 was obtained in the same manner as in Production Example B-1, except that hydrolysis was performed at 125 ° C. and that 10 parts by mass of the hydrophobizing agent was used for each solid component.

(Titanium oxide production example B-7)
Titanium oxide B-7 was obtained in the same manner as in Production Example B-1, except that hydrolysis was performed at 160 ° C. and that 5 parts by mass of the hydrophobizing agent was used for each solid component.

(Titanium oxide production example B-8)
After titanium tetrachloride was baked at 1000 ° C. in the gas phase, titanium oxide particles in which anatase form and rutile form were mixed were obtained. This titanium oxide is dispersed in ethanol, and 100 parts by mass of titanium oxide, i-butyltrimethoxysilane as a hydrophobizing agent is 10 parts by mass in a solid form, and sufficiently stirred so that particles are not coalesced. While mixing, the mixture was reacted. Further, the pH of the slurry was adjusted to 6.5 with sufficient stirring.

  This was filtered and dried, then heat-treated at 170 ° C. for 2 hours, and then repeatedly pulverized by a jet mill until titanium oxide aggregates disappeared to obtain titanium oxide B-8.

(Inorganic fine particle production example 1)
After silicon tetrachloride was baked in the gas phase at 1000 ° C., amorphous silica particles were obtained. This silica is dispersed in the middle gas phase, and 100 parts by mass of titanium oxide is sprayed with 15 parts by mass of hexamethyldisilazane (HMDS) as a hydrophobizing agent in a solid form so that particle coalescence does not occur. The reaction was conducted with sufficient stirring. Furthermore, with sufficient stirring, 15 parts by mass of dimethyl silicone oil was sprayed as a solid component, and the reaction was performed with sufficient stirring so that particle coalescence did not occur.

  After drying, this was heat-treated at 130 ° C. for 2 hours, and then repeatedly crushed by a jet mill until aggregates disappeared to obtain silica-1.

(Inorganic fine particle production example 2)
Silica-2 was obtained in the same manner as in inorganic fine particle production example 1 except that it was not treated with dimethyl silicone oil.

Resin production example (Hybrid resin production example 1)
As a vinyl copolymer, 1.9 mol of styrene, 0.21 mol of 2-ethylhexyl acrylate, 0.15 mol of fumaric acid, 0.03 mol of α-methylstyrene dimer, and 0.05 mol of dicumyl peroxide are put into a dropping funnel. . In addition, 7.0 mol of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane; Put 0 mol, 3.0 mol of succinic acid, 2.0 mol of trimellitic anhydride, 5.0 mol of fumaric acid and 0.2 g of dibutyltin oxide in a 4-liter 4-neck flask made of glass, thermometer, stir bar, condenser and nitrogen The introduction tube was installed and placed in a mantle heater. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually increased while stirring, and while stirring at a temperature of 145 ° C., the monomer of the vinyl resin, the crosslinking agent and the polymerization initiator were added from the previous dropping funnel. It was dripped over 4 hours. Subsequently, the temperature was raised to 200 ° C. and reacted for 4 hours to obtain a hybrid resin (1). The results of molecular weight measurement by GPC are shown in Table 2.

(Polyester resin production example 1)
3.6 mol of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 1.6 mol of polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 1.7 mol of terephthalic acid, 1.1 mol of trimellitic anhydride, 2.4 mol of fumaric acid and 0.1 g of dibutyltin oxide are placed in a 4-liter 4-neck flask made of glass, a thermometer, a stir bar, a condenser and a nitrogen inlet tube Was installed in a mantle heater. Under a nitrogen atmosphere, reaction was performed at 215 ° C. for 5 hours to obtain a polyester resin (1). The results of molecular weight measurement by GPC are shown in Table 2.

(Production example 1 of vinyl resin)
1000 ml of toluene solvent and vinyl copolymer, 2.4 mol of styrene, 0.26 mol of n-butyl acrylate, 0.09 mol of monobutyl malate, 0.11 mol of di-t-butyl peroxide, thermometer, stainless steel stirring Put into a 3 liter four-necked flask equipped with a rod, a flow-down condenser and a nitrogen inlet tube, and react in a mantle heater while stirring at 120 ° C in a nitrogen atmosphere while refluxing toluene. (1) was obtained. The results of molecular weight measurement by GPC are shown in Table 2.

Release agent production examples Table 3 shows release agents used in the present invention.

(Wax A)
Normal paraffin wax: wax A (melting point: 69.3 ° C.) obtained by purifying a hydrocarbon synthesized by the age method by a press sweating method was used.

(Wax B)
Benzene, a long-chain alkylcarboxylic acid component, a long-chain alkyl alcohol component, and p-toluenesulfonic acid are dissolved and stirred, and then azeotropically distilled off. The product was thoroughly washed with sodium hydrogen carbonate, dried, recrystallized, washed and purified, and ester wax: wax B (melting point: 72.7 ° C.) obtained was used.

(Wax C)
The normal paraffin wax: wax C (melting point: 51.0 ° C.) obtained without sufficiently purifying the hydrocarbon synthesized by the age method was used.

(Wax D)
Polyethylene wax: wax D (melting point: 95.7 ° C.) obtained by polymerization at low pressure with a Ziegler catalyst was used.

(Wax E)
Alcohol-modified polyethylene wax having a high melting point: Wax E (melting point: 108.9 ° C.) was used.

[Example 1]
Hybrid resin (1) 100 parts by weight Phthalocyanine pigment (cyan colorant) 4 parts by weight Aluminum complex of di-tert-butylsalicylic acid (negative charge control agent)
3 parts by weight Wax A 4 parts by weight The above compound is sufficiently premixed with a Henschel mixer, melt-kneaded with a twin-screw extruder kneader, cooled and roughly crushed to about 1 to 2 mm using a hammer mill, and then air Finely pulverized by a jet type fine pulverizer. Further, the obtained finely pulverized product was classified to obtain negative frictionally chargeable nonmagnetic cyan toner particles having a weight average particle diameter of 6.1 μm.

  100 parts by mass of the above cyan toner particles, titanium oxide A-1: 0.2 parts by mass, titanium oxide B-1: 1.0 parts by mass, and silica 1: 1.0 parts by mass are mixed with a Henschel mixer, and nonmagnetic. Cyan toner 1 was obtained. The obtained cyan toner 1 had a weight average particle diameter of 6.0 μm.

Carrier obtained by coating the above-mentioned cyan toner 1 and Mn-Mg ferrite particles with an aminosilane coupling agent-containing silicone resin (carrier particle size: 45 μm, resin coating amount: 0.5 parts per 100 parts by mass of carrier core particles) 2 parts by mass of N, N-dimethylaminotrimethoxysilane added: 5 parts by mass with respect to 100 parts by mass of silicone resin) to produce a two-component developer, and color copier CLC The image was output at -800 (manufactured by Canon, monochrome mode A4 size 28 sheets / minute). At that time, the fixing unit of the color copying machine uses a modified fixing machine without an oil application mechanism, and the photosensitive drum is a photosensitive drum having a 10-point average roughness of 1.1 μm whose surface layer is polished with a # 500 polishing sheet. It was. Then, a 20,000 sheet printing test was performed using an original document with an image area ratio of 25% under a high temperature and high humidity environment (35 ° C / 90%), and under a normal temperature and low humidity environment (23 ° C / 5%). Then, a printing test of 10,000 sheets was performed using an original document having an image area ratio of 5%, and then a printing test of 10,000 sheets was performed using an original document having an image area ratio of 25%. The toner application amount per unit area was set to 0.6 mg / cm ² and a printing durability test was performed.

  As a result, the image density transition was stable regardless of the environment, a high-quality image without line omission was stably obtained, and the fixing temperature range was wide and good results were obtained. Table 5 shows the results of the following evaluation items and criteria.

(Evaluation items and criteria)
○ Measurement of OHP transparency The measurement of OHP transparency is Shimadzu spectrophotometer UV2200 (manufactured by Shimadzu Corporation).
, The transmittance of the OHP film alone is 100%,
For magenta toner: 650 nm
For cyan toner: 500 nm
For yellow toner: 600 nm
The transmittance at the maximum absorption wavelength at is measured.
A: 85% or more B: 75-85%
C: 65-75%
D: Less than 65%

○ Measurement of Macbeth image density Indicates the image density measured by outputting a solid black image having a document image density of 1.7 in a single color using a Macbeth reflection densitometer (manufactured by Macbeth).

○ Measurement of transfer efficiency In a drawing experiment of the example and the comparative example, using a chart capable of forming a plurality of circle or band images, the density of the transfer remaining part on the drum and taped on the paper is D1, the density on the paper The density of the tape transferred onto the tape and D2 is D2. In the present invention, an image having a Macbeth image density of 1.0 was used in each image output environment, and the initial and post-endurance measurements were performed.

      Transfer efficiency (%) = D2 / (D1 + D2) × 100.

○ Evaluation of fog Fog is measured using a Tokyo Denshoku Ltd. REFRECTOMETER MODEL TC-6DS, in the cyan toner image using amber filter was calculated from the following equation. Smaller values indicate less fog.

Fog (reflectance) (%) = reflectance of standard paper (%)-reflectance of non-image part of sample (%)
A: Fog is 1.0% or less, which is a good level.
B: 1.0% to 2.0%, which is a level having no practical problem.
C: 2.0 to 4.0%, which is a practically problematic level.
D: It is 4.0% or more and is a level which cannot be used practically.

○ Observe the toner contamination around the developing device after the toner scattering endurance.
A: Stain due to toner around the developing device and the developing device in the main body is not observed at all.
B: Stain due to a small amount of toner is observed in the developing device, but at a level where there is no practical problem.
C: Stain due to toner around the developing device and the developing device in the main body is observed, and this is a practically problematic level.
D: The periphery of the developing device and the developing device in the main body is extremely dirty with toner, adversely affecting the function of the main body, and is not practical.

○ Highlight reproducibility Macbeth image density 0.3, 0.4, and 0.5 images are output, and density uniformity and roughness are visually evaluated.
A: A good output image with excellent uniformity of image density.
B: Image density uniformity is slightly lacking, but it is at a level where there is no practical problem.
C: Output image with poor and uniform image density, which is a practically problematic level.
D: Image density uniformity is remarkably poor, and the output image is harsh and is not practical.

○ Measure the surface of the photoconductor after durability on the surface of the photoconductor with 30 scanning electron microscopes.
A: Deposits such as toner and scratches are not observed.
B: Deposits such as toner and scratches are observed in several places, but they do not appear as image defects, and there is no practical problem.
C: Adhering material such as toner and scratches are observed at 10 or more places, appearing as image defects, and causing a practical problem.
D: A lot of deposits and scratches such as toner are observed, appear as remarkable image defects, and cannot be used practically.

[Examples 2 to 17, Comparative Examples 1 to 7]
Cyan toners 2 to 21, magenta toner 1, yellow toner 1 and black toner 1 were prepared using the materials shown in Tables 4 and 5 and evaluated in the same manner as in Example 1. The results are shown in Table 5. Note that magenta toner 1 has C.I. I. Pigment Red 57 was used in an amount of 6 parts by mass, and Yellow Toner 1 contained C.I. I. A toner was prepared in the same manner as in Example 1 except that 6 parts by mass of Pigment Yellow 74 was used and 6 parts by mass of carbon black was used as the colorant.

Claims (10)

In a toner having at least a resin, a colorant, a release agent, and inorganic fine particles,
The inorganic fine particles have at least two kinds of titanium oxides. One of the crystal forms of the titanium oxide is an anatase form and the other is a rutile form. The number average particle diameter of the titanium oxide is one of Is a toner characterized in that Da: more than 20 nm and not more than 60 nm, and the other Db: not less than 40 nm and not more than 100 nm, and Da <Db.   As the titanium oxide, titanium oxide A has a crystal form of anatase and a number average particle diameter of Da: more than 20 nm and not more than 60 nm, and titanium oxide B has a crystal form of a rutile form and a number average particle diameter of Db: 40 nm or more. The toner according to claim 1, wherein the toner is 100 nm or less and Da <Db.   The titanium oxide A has an intensity ratio (Ia / Ib) of an intensity Ia of 2θ = 25.3 and a minimum intensity Ib of 2θ = 20 to 30 deg in an X-ray diffraction of 5.0 ≦ Ia / Ib ≦ 12.0. The toner according to claim 1, wherein the toner is a toner.   4. The toner according to claim 1, wherein the titanium oxide A is obtained by surface-treating metatitanic acid having anatase-type crystallinity.   The toner according to any one of claims 1 to 4, wherein the addition amount ratio of the titanium oxide A and the titanium oxide B is 1: 2 to 1: 9.   6. The toner according to claim 1, wherein the surface treatment agent for titanium oxide B contains at least a fluorine-containing silane compound.   The toner according to claim 1, wherein the inorganic fine particles contain silica.   The toner according to claim 1, wherein the inorganic fine particles include oil-treated silica.   The toner according to claim 7 or 8, wherein the silica has an average particle diameter of 10 to 50 nm. The toner according to claim 1, wherein the resin is a hybrid resin.