JP2006243217A - Toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide toner excellent in transferability and environmental stability with which a high-quality image can be obtained. <P>SOLUTION: The toner comprises toner particles containing at least a binder resin, a colorant and a release agent, and at least silica particles, wherein the toner shows 10 to 70% transmissivity in a 45% MeOH solution, and the silica particles are subjected to the surface treatment by hydrolysis of a metal alkoxide expressed by general formula (1): M(OR)n. In formula (1), M represents a metal element, R represents an alkyl group, and n is an integer. When n is ≥2, R may be identical alkyl groups or a plurality of groups with different carbon numbers and structures. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a toner used for an image forming method such as an electrophotographic method, an electrostatic recording method, an electrostatic printing method, and a toner jet method, particularly a toner suitable for oilless fixing.

  The present invention relates to a color toner used in an image forming method such as an electrophotographic method, an electrostatic recording method, an electrostatic printing method, and a toner jet method, particularly a color toner suitable for oilless.

  In electrophotography, an electrostatic latent image formed on the surface of an electrostatic image carrier (photoconductor) is developed with toner containing a colorant, and the resulting toner image is transferred via / without an intermediate transfer member. An image is obtained by transferring the image onto a material and fixing it with a heat roll or the like. On the other hand, the electrostatic charge image carrier and the intermediate transfer member are cleaned again to form an electrostatic latent image. . The dry developer used in such electrophotography is a one-component developer using a toner in which a colorant or the like is blended in a binder resin, and a two-component developer in which a carrier is mixed with the toner. Broadly divided. In a one-component developer, magnetic powder is used, conveyed to an electrostatic charge image carrier (photoreceptor) by magnetic force, and developed into a static charge image carrier by applying a charging roll or the like without using a magnetic single component and magnetic powder to be developed. It can be classified as a non-magnetic one component to be conveyed and developed. Since the latter half of the 1980s, the market for electrophotography has been strongly demanded for miniaturization and high functionality with the key to digitization, and in particular, high-quality prints close to high-quality printing and silver halide photography are desired for full color image quality.

  Digitization processing is indispensable as a means for achieving high image quality, and the effect of digitization related to such image quality is that complex image processing can be performed at high speed. This makes it possible to control characters and photographic images separately, and the reproducibility of both qualities is greatly improved compared to analog technology. In particular, for photographic images, gradation correction and color correction are possible, and this is advantageous over analog in terms of gradation characteristics, definition, sharpness, color reproduction, and graininess. However, on the other hand, it is necessary to faithfully form a latent image created by an optical system as an image output, and the toner particles are becoming increasingly smaller in particle size and activities aiming at faithful reproduction are accelerated.

  However, when the particle diameter of the toner decreases, the charge amount per unit weight tends to increase, resulting in a decrease in image density and deterioration in durability. One of the causes is a decrease in the toner development amount with respect to the latent image on the photoreceptor. The other is a reduction in the efficiency of transferring the toner image on the photosensitive member or intermediate transfer member onto paper or the like. In general, the toner is electrically transferred from the photosensitive member to paper or the like. However, when the particle diameter of the toner is reduced, the non-electrostatic adhesion force is relatively increased, thereby lowering the efficiency. It is because.

  Various methods and apparatuses have been developed for fixing a toner image on a sheet such as paper. Conventionally, for the purpose of preventing the toner from adhering to the surface of the fixing member, the toner is formed of a material having excellent releasability, and the surface of the releasable material such as silicone oil is used to prevent offset and roller surface fatigue on the surface. The roller surface is coated with a good liquid film.

  However, this method is extremely effective in preventing toner offset, but has a problem that the fixing device is complicated because an apparatus for supplying the liquid for preventing offset is necessary. This is opposite to the reduction in size and weight, and silicone oil may evaporate due to heat and contaminate the interior of the machine. Therefore, instead of using a silicone oil supply device, instead of trying to supply an offset prevention liquid from the toner during heating, a release agent such as low molecular weight polyethylene, low molecular weight polypropylene or ester wax is added to the toner. A method has been proposed.

  The effect of including a release agent in the toner is not so much pressure at the time of fixing, and appears prominently in the fixing configuration in which the release agent is deposited on the toner surface by melting and fixed, but in the vicinity of the toner surface. If no release agent is present, the releasability with the fixing member cannot be sufficiently exhibited and the fixability is poor. Particularly in today's colorization, in order to express colors by mixing colors, a large amount of toner is inevitably fixed at one time, so that the use of a release agent having a low melting point effective for fixing becomes a problem.

  Furthermore, for toners containing a release agent by the pulverization method, the release agent present in the vicinity of the toner surface is significantly different in charging performance from resin, so no matter how highly charged material can be put in the resin, charging is necessary. It was difficult to make it uniform. Further, when a release agent is present in the vicinity of the toner surface, particularly when a large amount of the release agent is present in an uneven manner, the fluidity of the developer is deteriorated as compared with a toner having no internal release agent. In addition, during a long period of printing a plurality of sheets, a release agent may contaminate a charge imparting member such as a developing sleeve or a carrier that the toner strongly rubs against, thereby reducing developability. As described above, since the amount of the release agent in the vicinity of the toner surface affects the overall electrophotographic characteristics, it is important that the release agent exists in the vicinity of the toner surface in a balanced manner.

  Even for a toner having a release agent, in order to further improve the charging uniformity and fluidity, it is important to consider external addition using inorganic fine particles.

  On the other hand, as a full-color transfer material, in addition to ordinary paper and overhead projector film (OHP), there is an increasing need for various materials to be used on cardboard, card, postcard and other small-size paper. The transfer method using is becoming effective. In a system that normally uses an intermediate transfer member, it is necessary to transfer the developed color image of the toner from the photosensitive member to the intermediate transfer member, and then transfer it again from the intermediate transfer member onto the transfer material, which is compared with the conventional method. Therefore, it is necessary to improve the transferability of toner more than before. In particular, in the case of using a full-color copying machine that transfers a plurality of toner images after development, the amount of toner on the photoconductor increases as compared with the case of one-color black toner used in a black-and-white copying machine. It is difficult to improve transferability only by use.

  Therefore, in recent years, as one of the techniques for improving the transferability, the toner shape has been made closer to a spherical shape. For example, a polymerization toner such as suspension polymerization or emulsion polymerization, a method of spheroidizing a pulverized toner in a solvent (for example, see Patent Document 1), a method of spheronizing with hot air (for example, see Patent Document 2), mechanical impact A method of making a sphere by force (for example, see Patent Document 3) is known. These techniques are very effective techniques for improving transferability.

  However, these techniques are very effective means for improving transferability. However, since the release agent is included in the polymerized toner, the release agent always appears on the toner surface when no pressure is applied during fixing. It becomes difficult and the fixing ability is inferior. Further, when the spheroidization is attempted by mechanical impact force, the more the spheronization is progressed, the more easily the release agent is eluted on the toner surface by heat, which adversely affects the electrophotographic characteristics.

  It is highly expected that the fluidity of the toner will deteriorate due to the release of the release agent on the toner surface. Further, the adhesion between the toners and between the toner and the carrier is increased, so that the powder separation is worsened and the transferability is impaired. In view of this, it is important for the release agent-added toner that the developer is configured so that both transferability and fluidity problems can be satisfied.

  In addition, as described above, the transferability is improved by making the toner spherical, but on the other hand, the transfer residual toner generated slightly causes a cleaning failure. On the other hand, a cleanerless system has been proposed in which the cleaning system is omitted and toner remaining on the photosensitive drum after transfer is recovered simultaneously with development by a developing device (see, for example, Patent Document 4 and Patent Document 5). Generally, when residual toner is collected simultaneously with development in this way, the collected toner and other toners have different chargeability, and the collected toner accumulates in the developing unit without being developed. Therefore, it is necessary to further improve the transferability and control the amount of collected toner to a minimum. Even if the transfer residual toner is minimized, the free external additive is fused and contaminated on the photosensitive drum.

  Under the circumstances as described above, in order to make full use of a small particle size toner having a release agent, it is necessary to manipulate not only the toner particles but also the composition or shape of the external additive.

  In the case of a small particle size toner, the gravity per particle is inversely proportional to the cube of the particle size, so it is easily expected that the fluidity of the toner particles will greatly deteriorate. Therefore, it is important that the developer is configured so that the charging problem and the fluidity problem are compatible, particularly in the case of a small particle toner having a release agent. However, it is difficult to satisfy these requirements by external addition of silica particles, which is a commonly used external additive. This is due to the fact that the silica particles themselves are strongly negatively charged. For this reason, the toner to which silica is added has a large charge amount fluctuation in a high temperature and high humidity or low temperature and low humidity environment. For example, background toner stains and in-machine stains occur in a high-temperature and high-humidity environment, and the image density tends to decrease in a low-temperature and low-humidity environment.

  In order to improve the fluidity of the toner, conventionally, it has been proposed to use silica particles or the like as an external additive (see, for example, Patent Document 6) and further use hydrophobized silica particles. (For example, see Patent Document 7, Patent Document 8, and Patent Document 9). For example, silica fine powder powder is used in which silica particles are reacted with an organic silicon compound such as dimethyldichlorosilane to replace the silanol group on the surface of the silica fine powder with an organic group to make it hydrophobic. However, although the fluidity of the toner is improved by the addition of an external additive such as silica, the silica fine particles are highly cohesive, so that suspended matter such as silica soul increases. Further, the suspended silica has strong adhesion to the photoreceptor and may be fused.

  When a pressing force is applied to the photoconductor during the process of forming an image, this silica suspended material serves as a nucleus, which is driven into the photoconductor to cause scratches, or a so-called toner in which the toner is fixed on the photoconductor as a trigger Filming occurs. When this filming occurs, the surface potential is unlikely to drop when the charged photosensitive member is exposed. For example, in reversal development, an image defect occurs in which a solid black image portion is whitened.

  Silica floating matter adheres to the solid black image portion, and white spot noise is generated. In particular, in a configuration in which the intermediate transfer member is in contact with the photosensitive member at a constant pressure in the transfer process, a pressing force is received from the intermediate transfer member.

  Therefore, the developer and the photoconductor are in contact with each other for a long time, and silica is more easily attached to the photoconductor.

  Further, various studies have been made in order to make full use of toner having a small particle size so that both the charging problem and the fluidity problem are compatible (see, for example, Patent Document 10, Patent Document 11, and Patent Document 12). . Patent Document 10 discloses that a toner having an average particle diameter of 8 μm or less satisfies charging characteristics and transferability by using a relatively small amorphous titania and a relatively large silica in combination. However, in practice, toner particles having an average particle diameter of 6 μm or less have a relatively large and insufficient change in charging property. Patent Document 11 discloses that inorganic particles or organic spherical particles of 20 to 80 nm are added to toner particles having a size of 9 μm or less. In this case, although the transferability is effective, the charging property is insufficient. Met.

  Patent Document 12 discloses that fumed silica is surface-treated with a metal alkoxide. In this case, although the charging uniformity and fluidity under normal temperature and normal humidity are effective, the environmental stability, particularly the charging stability under high temperature and high humidity, was insufficient.

  On the other hand, in order to improve the developability, transferability, and cleaning properties of the toner, two types of inorganic fine particles having different average particle diameters, particles having an average particle diameter of 5 mμ to 20 mμ and particles having an average particle diameter of 20 mμ to 40 mμ, respectively. And adding a specific amount is disclosed (for example, see Patent Document 13). In the initial stage, high developability, transferability, and cleaning properties can be obtained. However, both flowability and transferability cannot be achieved over time.

  Furthermore, it is disclosed that the use of monodispersed spherical silica obtained by a sol-gel method is effective for transferability (see, for example, Patent Document 14). Although this method can surely obtain a high transferability initially, the silica particles are large, so that the external attachment property to the toner particles becomes insufficient, the toner particles are easily separated from the toner particles, and are fused to the photoreceptor. It cannot be solved. Moreover, since the silica particles obtained by the sol-gel method have high hygroscopicity, environmental stability is poor, and stable images cannot be obtained during long-term use.

  In addition, any inorganic fine particles, particularly silica particles, have strong adhesion to the photoreceptor, and melt and easily cause image defects.

  As described above, there is a need for further improvements for small particle size toners containing release agents. In particular, a small particle size toner containing a release agent having a low melting point has a great influence on electrophotographic characteristics. Therefore, a toner that has further excellent charging characteristics, transferability, and durability is required.

Japanese Patent Laid-Open No. 11-44969 JP 2000-29241 A Japanese Patent Laid-Open No. 7-181732 Japanese Patent Laid-Open No. 2-302772 JP-A-5-94113 Japanese Patent Publication No.54-16219 JP-A-46-5782 JP-A-48-47345 JP-A-48-47346 JP-A-4-348354 Japanese Patent Laid-Open No. 4-337738 Japanese Patent Laid-Open No. 2004-155648 Japanese Patent Laid-Open No. 3-100161 JP 2001-0666820 A

  An object of the present invention is to provide a toner capable of achieving both high transferability and fluidity, excellent environmental stability, and obtaining a high-quality image.

  As a result of intensive studies, the present inventors have found that the above requirements can be satisfied by controlling the amount of the surface release agent of the toner and using specific inorganic fine particles as an external additive. That is, the above object can be solved by using the following toners (i) and (ii).

[Toner of (i)]
In at least toner particles having a binder resin, a colorant and a release agent, and at least toner having silica particles,
The transmittance of the toner in 45% MeOH is 10 to 70%,
The toner, wherein the silica particles are silica particles (soot) that has been surface-treated by hydrolyzing a metal alkoxide represented by the following general formula (1).
M (OR) n (1)
(However, M represents a metal element, R represents an alkyl group, and n represents an integer. When n is 2 or more, R may be the same alkyl group or a plurality of alkyl groups having different carbon numbers and structures. Good.)

[Toner (ii)]
At least toner particles having a binder resin, a colorant and a release agent, and a toner having at least two kinds of inorganic fine particles (B) and inorganic fine particles (C),
At least one of the inorganic fine particles (B) and the inorganic fine particles (C) is a silica particle which is surface-treated by hydrolyzing at least the metal alkoxide represented by the general formula (1). .

  In the toner of the present invention, the optimum presence state of the release agent on the toner surface is carried out, and silica particles surface-treated with metal alkoxide and inorganic fine particles are externally added, so that the toner has high transferability and fluidity. To achieve high image quality.

  Furthermore, high durability, environmental stability, and charging stability can be achieved.

  In the toner of the present invention, since silica particles and inorganic fine particles added externally are surface-treated with a metal alkoxide by an optimum treatment method, the inorganic fine particles, particularly silica particles are originally externally added to the toner. In addition, problems caused by aggregation of inorganic fine particles, for example, image defects due to adhesion of external additives to a photoreceptor or the like can be solved.

  In the toner containing a release agent, the present inventors have intensively studied the amount of the release agent present on the toner surface, the kind of inorganic fine particles (external additive), and the amount thereof, and as a result, have solved the above-described problems. Has been found, and the present invention has been completed.

  In the present invention, the amount of the release agent on the surface of the toner is controlled.

  The amount of the release agent in the vicinity of the desired surface in the present invention can be easily and accurately grasped with respect to the entire toner particles by measuring the transmittance in a 45 volume% methanol aqueous solution. In this measurement method, the toner is forcibly dispersed once in a mixed solvent to facilitate the influence of the surface existing amount of the release agent for each toner particle, and the transmittance after a certain time is measured. Thus, it is possible to accurately grasp the surface existing amount of the release agent in the entire toner. In other words, when a large amount of hydrophobic release agent is present on the toner surface, it becomes difficult to disperse in the solvent and agglomerates, resulting in a high transmittance. On the contrary, if the release agent is not present on the toner surface, it is uniformly dispersed and the transmittance becomes a small value.

  In the present invention, the desired transmittance is such that the transmittance α (%) in a 45% by volume aqueous solution of methanol is 10 ≦ α ≦ 70, and preferably 15 ≦ α ≦ 50. If the value of α is less than 10, the release agent on the toner surface is small and the releasing effect is difficult to appear at the time of fixing. Requires the required load. On the other hand, if it is larger than 70, there are many release agents on the toner surface, and even if silica particles (A), inorganic fine particles (B) and (C) described later are externally added, the fluidity of the developer deteriorates, Fog, image density uniformity, and image density stability are likely to deteriorate. In addition, the member in contact with the toner is contaminated and, for example, the resistance is increased by fusing on the developing sleeve, so that the effect of the actual developing bias for developing is lowered, and the image density may be lowered.

  Here, in comparison with the physical properties of the conventional toner, in the toner that does not use a release agent or a polymerized toner, since the hydrophobic release agent does not exist on the toner surface, the transmittance is small, and the transmittance α is Less than 10. Even when a release agent is used, when the amount is small or the toner surface is extremely small, the transmittance α is less than 10%, which is insufficient for fixing properties.

  The shape of the toner of the present invention is preferably such that the average circularity β is 0.915 ≦ β ≦ 0.990, more preferably 0 for particles having an equivalent circle diameter of 3 μm or more for the purpose of improving transferability. .920 ≦ β ≦ 0.970, more preferably 0.940 ≦ β ≦ 0.965. If the value of β is less than 0.915, even if silica particles (A), inorganic fine particles (B), and (C) described later are externally added, transferability, particularly transfer efficiency, may be inferior. If it is greater than 0.990, the image forming apparatus having a cleaning mechanism in the photosensitive drum unit slips through the cleaning blade, and image defects due to poor cleaning are likely to occur.

  In the present invention, in order to obtain a pulverized toner having the desired shape and performance as described above, in the step of producing the toner, a step of applying a mechanical impact force while discharging the generated fine powder out of the system (the step) The present inventors have confirmed that it is effective to apply the following details. In other words, in the pulverization step and the spheronization step, even if each step is performed alone or both steps are performed simultaneously, if the generated fine powder is not discharged while being discharged out of the system, Since a very small fine powder generated during the spheronization process aggregates and causes irregularities in the particle shape, a mechanical impact force is required more than necessary to achieve the desired sphericity, resulting in an excess amount of heat and resulting in a toner surface. As a result, the amount of the mold release agent increases, causing a harmful effect. In addition, the small fine powder is one of the major factors that worsen the spent on the carrier used in the two-component developer. When the particles pulverized by the mechanical impact force are put on an air stream as they are and introduced into the classifying section without stopping the air stream, the fine powder is efficiently discharged out of the system without re-aggregation. From the above, when a mechanical impact force is applied while discharging the generated fine powder out of the system, the toner shape, the fine powder amount, and the amount of the release agent can be controlled as desired. Thus, the pulverized toner of the present invention that satisfies the above requirements obtained by considering the balance between the degree of the sphere and the amount of the release agent etc. on the surface of the pulverized toner is not simply spheroidized. The problems of the conventional toner described above can be solved.

  When the toner is manufactured by a method different from the above manufacturing method, the values of the transmittance α and the average circularity β defined in the present invention tend to be as follows, for example.

  When toner is manufactured using a spheroidizing method such as a hybridization system manufactured by Nara Machinery, the extremely small fine powder generated during pulverization cannot be removed, so the rotational speed is increased more than necessary or the residence time is increased. As a result, too much heat is applied, the amount of the release agent present on the toner surface increases, and the value of the transmittance α tends to exceed 70.

  In addition, when toner is manufactured using a kryptron system manufactured by Kawasaki Heavy Industries, Ltd., a super rotor manufactured by Nisshin Engineering Co., Ltd., which simultaneously performs pulverization and spheronization, a large amount of heat is generated because it is not possible to remove fairly small fine particles generated during pulverization as described above. The value of the transmittance α is likely to exceed 70.

  In addition, when toner is manufactured using a surfing system manufactured by Nippon Pneumatic Co., Ltd., which is applied with heat to form a sphere, of course, the value of the transmittance α exceeds 70 because of a considerable amount of heat. Cheap.

  In a toner using a release agent, when the toner is manufactured by an air jet method, the desired circularity β is less than 0.915 although the desired transmittance α can be 10 ≦ α ≦ 70. The value of is difficult to get.

  In addition, in the polymerized toner, a desired transmittance can be obtained by adjusting the type, amount, dispersion condition, emulsification condition, aggregation condition, washing condition, drying temperature / treatment time, etc. of the release agent. . The polymerized toner of the present invention that satisfies the above requirements obtained by considering the balance with the amount of the release agent or the like on the surface of the toner can solve the above-described problems of the conventional toner. .

  Further, in the toner of the present invention, a more preferable toner can be obtained when the requirement defining the particle size of the toner is satisfied in addition to the above requirement.

  The toner of the present invention preferably has a weight average particle size X of more than 3.0 μm and 11.0 μm or less, and more preferably 4.0 to 9.5 μm. When the weight average particle diameter is 3.0 μm or less, toner aggregation or fog tends to occur, and when the weight average particle diameter exceeds 11.0 μm, a high-definition image can be obtained. It becomes difficult.

  In the present invention, the transmittance α, the average circularity β, and the weight average particle size X are measured as follows. In addition, it measured similarly also in the below-mentioned Example.

<Transmissivity α in a 45% by volume methanol aqueous solution>
(I) Preparation of toner dispersion An aqueous solution having a volume mixing ratio of methanol: water of 45:55 is prepared. 10 ml of this aqueous solution is placed in a 30 ml sample bottle (Nippon Denka Glass: SV-30), and 20 mg of toner is impregnated on the liquid surface to cover the bottle. Then, shake for 5 seconds at 150 reciprocations / minute with a Yayoi-type shaker (model: YS-LD). At this time, the angle of shaking is such that the shaking column moves 15 degrees forward and 20 degrees backward, assuming that the vertical (vertical) of the shaker is 0 degree. And it is shaken once forward and backward once, and when returning to just above, it counts as one reciprocation. The sample bottle is fixed to a fixing holder (with the sample bottle lid fixed on the extension at the center of the column) attached to the tip of the column. After removing the sample bottle, the dispersion after standing for 30 seconds is used as a measurement dispersion.

(Ii) Transmittance measurement The dispersion obtained in (i) is placed in a 1 cm square quartz cell, and the transmittance at a wavelength of 600 nm of the dispersion after 10 minutes using a spectrophotometer MPS2000 (manufactured by Shimadzu Corporation) ( %) (See next formula).
Transmittance α (%) = I / I0 × 100
(I0 is an incident light beam and I is a transmitted light beam.)

<Measurement of average circularity β>
The equivalent circle diameter, circularity, and frequency distribution of the toner are used as a simple method for quantitatively expressing the shape of the toner particles. In the present invention, the flow type particle image measuring device “FPIA-2100 type” is used. (Sysmex Corporation) is used for measurement and calculated using the following formula.

  Here, the “particle projected area” is the area of the binarized toner particle image, and the “peripheral length of the particle projected image” is the length of the contour line obtained by connecting the edge points of the toner particle image. Define. In the present invention, the circularity is an index indicating the degree of unevenness of the toner particles, and is 1.000 when the toner particles are completely spherical. The more complicated the surface shape, the smaller the circularity.

  In the present invention, the average circularity C, which means the average value of the circularity distribution, is calculated from the following equation, where the circularity (center value) at the dividing point i of the particle size distribution is ci and the frequency is fci.

  As a specific measuring method, 10 ml of ion-exchanged water from which impure solids have been removed in advance is prepared in a container, and a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant therein, followed by further measurement. Add 0.02 g of sample and disperse uniformly. As a means for dispersion, an ultrasonic disperser “Tetor β 150 type” (manufactured by Nikka Ki Bios) is used, and a dispersion process is performed for 2 minutes to obtain a dispersion for measurement. In that case, it cools suitably so that the temperature of this dispersion may not be 40 degreeC or more.

  To measure the shape of the toner particles, the flow type particle image measuring device is used, the concentration of the dispersion is readjusted so that the toner particle concentration at the time of measurement is 3000 to 10,000 / μl, and 1000 toner particles are obtained. Measure above. After the measurement, using this data, data of 3 μm or less is cut to determine the average circularity β of the toner particles.

<Measurement of Weight Average Particle Size X of Toner>
In the present invention, a Coulter Multisizer (manufactured by Coulter, Inc.) can be used for the average particle size and particle size distribution of the toner. As the electrolytic solution, a 1% NβCl aqueous solution prepared using primary sodium chloride may be used. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) may 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 electrolytic aqueous 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 of 2.00 μm or more are measured by using the 100 μm aperture as the aperture by the measuring device. The distribution and the number distribution are calculated to determine the weight average particle diameter (D4) (the median value of each channel is the representative value for each channel).

  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.

  As the binder resin for the toner used in the present invention, known resins exemplified below which are conventionally used for toner can be used. For example, styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, etc., and homopolymers thereof; styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer , Styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl Styrene copolymers such as ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer; polyvinyl chloride; phenol Resin; Naturally modified pheno Natural resin-modified maleic acid resin; acrylic resin; methacrylic resin; polyvinyl acetate; silicone resin; polyester resin; polyurethane; polyamide resin; furan resin: epoxy resin; xylene resin: polyvinyl butyral; A hybrid resin having a polyester unit and a vinyl polymer unit; a mixture of a hybrid resin and a vinyl polymer; a mixture of a hybrid resin and a polyester resin; a mixture of a polyester resin and a vinyl polymer; Resins can be used.

  Although not particularly limited, preferred binder resins include (α) a polyester resin, (β) a hybrid resin having a polyester unit and a vinyl polymer unit, or (c) a hybrid resin and a vinyl polymer. Or a resin selected from (d) a mixture of a hybrid resin and a polyester resin, or (e) or a mixture of a polyester resin and a vinyl polymer.

  (Α) In the case of using a polyester resin, alcohol and carboxylic acid, or carboxylic acid anhydride, carboxylic acid ester and the like can be used as raw material monomers. Specifically, for example, as the dihydric alcohol component, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,2-bis ( 4-hydroxyphenyl) propane, polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -polyoxyethylene (2.0) -2,2 -Bisphenol-alkylene oxide adducts such as bis (4-hydroxyphenyl) propane and polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane, ethylene glycol, diethylene glycol, triethylene glycol, 1, 2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, Opentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol And hydrogenated bisphenol soot.

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

  Acidic components include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid or their anhydrides; alkyl dicarboxylic acids such as oxalic acid, adipic acid, sebacic acid and azelaic acid or their anhydrides; 6-12 carbon atoms Succinic acid substituted with an alkyl group or an anhydride thereof; unsaturated dicarboxylic acids such as fumaric acid, maleic acid and citraconic acid or anhydrides thereof;

  Among them, in particular, a bisphenol derivative represented by the following general formula (2) as a diol component, a carboxylic acid component (for example, fumaric acid) composed of a divalent or higher carboxylic acid or an acid anhydride thereof, or a lower alkyl ester thereof. A polyester resin obtained by condensation polymerization of acid, maleic acid, maleic anhydride, phthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid and the like as an acid component is preferable as a toner because it has good charging characteristics.

  (Β) When a hybrid resin in a hybrid resin having a polyester unit and a vinyl polymer unit is used, further improved wax dispersibility, low-temperature fixability, and offset resistance can be expected. The “hybrid resin component” used in the present invention means a resin in which a vinyl polymer unit and a polyester unit are chemically bonded. Specifically, a polyester unit and a vinyl polymer unit obtained by polymerizing a monomer having a carboxylic acid ester group such as (meth) acrylic acid ester are formed by a transesterification reaction, preferably a vinyl polymer. Is used to form a graft copolymer (or block copolymer) having a backbone polymer and a polyester unit as a branch polymer.

  Examples of the vinyl monomer for producing the vinyl polymer unit or vinyl polymer in the present invention include the following. Styrene; o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert- Butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene, p-chloro styrene, 3, Styrene and derivatives thereof such as 4-dichlorostyrene, m-nitrostyrene, o-nitrostyrene, p-nitrostyrene; styrene unsaturated monoolefins such as ethylene, propylene, butylene and isobutylene; unsaturated such as butadiene and isoprene Polyenes; vinyl chloride, vinyl chloride, vinyl bromide, fluoride Vinyl halides such as vinyl; vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-methacrylate Α-methylene aliphatic monocarboxylic acid esters such as octyl, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate; methyl acrylate, ethyl acrylate Propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-acrylate Acrylic esters such as lorethyl and phenyl acrylate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and methyl isopropenyl ketone; N-vinyl pyrrole; N-vinyl compounds such as N-vinyl carbazole, N-vinyl indole and N-vinyl pyrrolidone; vinyl naphthalenes; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile and acrylamide.

  In addition, unsaturated dibasic acids such as maleic acid, citraconic acid, itaconic acid, alkenyl succinic acid, fumaric acid, mesaconic acid; maleic anhydride, citraconic anhydride, itaconic anhydride, alkenyl succinic anhydride, etc. Unsaturated dibasic acid anhydride; maleic acid methyl half ester, maleic acid ethyl half ester, maleic acid butyl half ester, citraconic acid methyl half ester, citraconic acid ethyl half ester, citraconic acid butyl half ester, itaconic acid methyl half ester, Alkenyl succinic acid half ester, fumaric acid methyl half ester, mesaconic acid methyl half ester unsaturated dibasic acid half ester; dimethylmaleic acid, dimethyl fumaric acid unsaturated dibasic acid ester; acrylic acid, meta Α, β-unsaturated acids such as rillic acid, crotonic acid and cinnamic acid; α, β-unsaturated acid anhydrides such as crotonic acid anhydride and cinnamic acid anhydride, the α, β-unsaturated acid and lower fatty acids And monomers having a carboxyl group such as alkenylmalonic acid, alkenylglutaric acid, alkenyladipic acid, acid anhydrides and monoesters thereof.

  Further, acrylic acid or methacrylic acid esters such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate; 4- (1-hydroxy-1-methylbutyl) styrene, 4- (1-hydroxy-1) -Methylhexyl) Monomers having a hydroxy group such as styrene.

  The vinyl polymer or vinyl polymer unit in the present invention may have a crosslinked structure crosslinked with a crosslinking agent having two or more vinyl groups, but the crosslinking agent used in this case is aromatic. Examples of the divinyl compound include divinylbenzene and divinylnaphthalene; examples of the diacrylate compound linked by an alkyl chain include ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6 hexanediol diacrylate, neopentyl glycol diacrylate, and those obtained by replacing acrylates of the above compounds with methacrylates; diacrylates linked by alkyl chains containing an ether bond As compounds, For example, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, dipropylene glycol diacrylate, and acrylates of the above compounds replaced with methacrylate Examples of diacrylate compounds connected by a chain containing an aromatic group and an ether bond include polyoxyethylene (2) -2,2-bis (4-hydroxyphenyl) propane diacrylate, polyoxyethylene ( 4) -2,2-bis (4-hydroxyphenyl) propane diacrylate and those obtained by replacing the acrylate of the above compound with methacrylate.

  Polyfunctional cross-linking agents include pentaerythritol triacrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate, tetramethylol methane tetraacrylate, oligoester acrylate, and acrylates of the above compounds replaced with methacrylate; triallylcia Examples include nurate and triallyl trimellitate.

  In the present invention, it is preferred that the vinyl polymer or unit and / or the polyester resin or unit contain a monomer component capable of reacting with both resin components. Among the monomers constituting the polyester resin or unit, those capable of reacting with the vinyl polymer or unit include, for example, unsaturated dicarboxylic acids such as phthalic acid, maleic acid, citraconic acid and itaconic acid, or anhydrides thereof. It is done. Among the monomers constituting the vinyl polymer or unit, those capable of reacting with the polyester resin or unit include those having a carboxyl group or a hydroxy group, and acrylic acid or methacrylic acid esters.

  As a method for obtaining a reaction product of a vinyl polymer and a polyester resin, either a polymer or a resin containing a monomer component capable of reacting with each of the vinyl polymer and the polyester resin listed above is present. A method obtained by polymerizing one or both of the polymers or resins is preferred.

  Examples of the polymerization initiator used in producing the vinyl polymer or vinyl polymer unit of the present invention include 2,2′-azobisisobutyronitrile, 2,2′-azobis (4- Methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis (-2,4-dimethylvaleronitrile), 2,2′-azobis (-2methylbutyronitrile), dimethyl-2,2′- Azobisisobutyrate, 1,1′-azobis (1-cyclohexanecarbonitrile), 2- (carbamoylazo) -isobutyronitrile, 2,2′-azobis (2,4,4-trimethylpentane), 2- Phenylazo-2,4-dimethyl-4-methoxyvaleronitrile, 2,2′-azobis (2-methyl-propane), methyl ethyl ketone peroxide, acetyla Ketone peroxides such as ton peroxide, cyclohexanone peroxide, 2,2-bis (t-butylperoxy) butane, t-butyl hydroperoxide, cumene hydroperoxide, 1,1,3,3-tetramethyl Butyl hydroperoxide, di-t-butyl peroxide, t-butylcumyl peroxide, di-cumyl peroxide, α, α'-bis (t-butylperoxyisopropyl) benzene, isobutyl peroxide, octanoyl peroxide Decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, benzoyl peroxide, m-trioyl peroxide, di-isopropyl peroxydicarbonate, di-2-ethylhexyl Ruperoxy dicarbonate, di-n-propyl peroxydicarbonate, di-2-ethoxyethyl peroxycarbonate, di-methoxyisopropyl peroxydicarbonate, di (3-methyl-3-methoxybutyl) peroxycarbonate, acetyl Cyclohexylsulfonyl peroxide, t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butyl peroxyneodecanoate, t-butyl peroxy 2-ethylhexanoate, t-butyl peroxylaurate T-butyl peroxybenzoate, t-butyl peroxyisopropyl carbonate, di-t-butyl peroxyisophthalate, t-butyl peroxyallyl carbonate, t-amyl peroxy 2-ethylhexanoate, -t- butyl peroxy hexahydro terephthalate, di -t- butyl peroxy azelate and the like.

  Examples of the production method capable of preparing the hybrid resin used in the toner of the present invention include the following production methods (1) to (6).

  (1) A method in which a vinyl polymer and a polyester resin are blended after production. The blend is produced by dissolving and swelling in an organic solvent (for example, xylene) and then distilling off the organic solvent. The hybrid resin component is synthesized by separately producing a vinyl polymer and a polyester resin, dissolving and swelling in a small amount of an organic solvent, adding an esterification catalyst and an alcohol, and performing a transesterification reaction by heating. Thus, a hybrid resin having a polyester unit and a vinyl polymer can be obtained.

  (2) A method of producing a hybrid resin component having a polyester unit and a vinyl polymer unit by producing and reacting a polyester resin in the presence of the vinyl polymer after production. The hybrid resin component is produced by a reaction between a vinyl polymer (a vinyl monomer can be added if necessary) and a polyester monomer (alcohol, carboxylic acid) and / or polyester resin. Also in this case, an organic solvent can be appropriately used.

  (3) A method for producing a hybrid resin component having a polyester unit and a vinyl polymer unit by producing and reacting a vinyl polymer in the presence of the polyester resin after production. The hybrid resin component is produced by a reaction between a polyester resin (a polyester monomer can be added if necessary) and a vinyl monomer and / or a vinyl polymer.

  (4) After the vinyl polymer and the polyester resin are produced, the hybrid resin component is produced by adding a vinyl monomer and / or a polyester monomer (alcohol, carboxylic acid) in the presence of these polymer units. Also in this case, an organic solvent can be appropriately used.

  (5) After producing a hybrid resin component having a polyester unit and a vinyl polymer unit, by adding a vinyl monomer and / or a polyester monomer (alcohol, carboxylic acid) and performing an addition polymerization and / or a condensation polymerization reaction. Vinyl polymers and / or polyester resins or even hybrids are produced. In this case, as the hybrid resin component having the polyester unit and the vinyl polymer unit, those produced by the production methods (2) to (4) can be used, and if necessary, by a known production method. What was manufactured can also be used. Furthermore, an organic solvent can be used as appropriate.

  (6) By mixing a vinyl monomer and a polyester monomer (alcohol, carboxylic acid, etc.) and continuously performing addition polymerization and condensation polymerization reaction, a vinyl polymer, a polyester resin, a polyester unit and a vinyl polymer unit are obtained. A hybrid resin component is produced. Furthermore, an organic solvent can be used as appropriate.

  In the production methods (1) to (6) above, the vinyl copolymer unit and / or the polyester unit can use a plurality of polymer units having different molecular weights and cross-linking degrees.

  In the present invention, the vinyl polymer or vinyl polymer unit means a vinyl homopolymer, a vinyl copolymer, a vinyl monopolymer unit, or a vinyl copolymer unit.

  The binder resin contained in the toner of the present invention includes a mixture of the polyester and vinyl copolymer, a mixture of the hybrid resin and vinyl copolymer, the polyester resin and the hybrid resin. A mixture of vinyl copolymers may be used.

  Next, a known pigment or dye can be used as the colorant contained in the toner of the present invention, and is not particularly limited. Examples of the pigment include the following. Examples of the color pigment for magenta include 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, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 83, 88, 90, 112, 122, 123, 163, 202, 206, 207, 209, C.I. I. Pigment violet 19, C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35, etc. are mentioned.

  Such a pigment may be used alone, but it is more preferable from the viewpoint of the image quality of a full-color image to improve the sharpness by using a dye and a pigment together. Examples of the magenta dye include C.I. I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121, C.I. I. Disper thread 9, C.I. I. Solvent Violet 8, 13, 14, 21, 27, C.I. I. Oil-soluble dyes such as disperse violet 1, C.I. I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, C.I. I. Basic dyes such as basic violet 1,3,7,10,14,15,21,25,26,27,28 are listed.

  As other coloring pigments, cyan pigments include C.I. I. Pigment blue 2, 3, 15, 16, 17, C.I. I. Bat Blue 6, C.I. I. Acid Blue 45 or a copper phthalocyanine pigment having 1 to 5 phthalimidomethyl groups substituted on the phthalocyanine skeleton.

Examples of the color pigment for yellow include 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, 147, 155, 180, C.I. I. Vat yellow 1, 3, 20 etc. are mentioned.
As the black colorant, carbon black, a magnetic material, and a color toned to black using the yellow / magenta / cyan colorant shown above can be used.

  In addition, it is preferable that the usage-amount of a coloring agent is 0.1-60 mass parts with respect to 100 mass parts of binder resin, and it is more preferable that it is 0.5-50 mass parts.

  Next, the mold release agent used in the present invention will be described.

  Examples of the release agent used in the present invention include the following. Oxides of aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, Fischer-Tropsch wax and paraffin wax, and aliphatic hydrocarbon waxes such as oxidized polyethylene wax, or block copolymerization thereof. Examples thereof include waxes mainly composed of fatty acid esters such as carnauba wax and montanic acid ester wax, and those obtained by partially or entirely deoxidizing fatty acid esters such as deoxidized carnauba wax. In addition, saturated linear fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as brandic acid, eleostearic acid, and valinal acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvir alcohol, and seryl alcohol , Saturated alcohols such as melyl alcohol; polyhydric alcohols such as sorbitol; fatty acid amides such as linoleic acid amide, oleic acid amide, lauric acid amide; methylene bis stearic acid amide, ethylene biscapric acid amide, ethylene bis laurin Saturated fatty acid bisamides such as acid amides and hexamethylene bis stearic acid amides; ethylene bis oleic acid amides, hexamethylene bis oleic acid amides, N, N ′ dioleyl adipic acid amides, N, N ′ diacids Unsaturated fatty acid amides such as rail sebacic acid amides; Aromatic bisamides such as m-xylene bisstearic acid amide and N, N ′ distearyl isophthalic acid amides; Calcium stearate, calcium laurate, zinc stearate, magnesium stearate Aliphatic metal salts such as those commonly referred to as metal soaps; waxes grafted with aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid; fatty acids such as behenic acid monoglycerides and the like Examples include partially esterified products of polyhydric alcohols; methyl ester compounds having hydroxyl groups obtained by hydrogenation of vegetable oils and the like.

  The toner of the present invention preferably contains one or more waxes. Furthermore, the toner of the present invention has one or more endothermic peaks in the temperature range of 30 to 200 ° C. in the endothermic curve in differential thermal analysis (DSC) measurement from the viewpoint of achieving both low-temperature fixability and blocking resistance. The peak temperature of the maximum endothermic peak in the endothermic peak is preferably in the range of 60 to 110 ° C. More preferably, the maximum peak of the endothermic curve is in the range of 65 to 100 ° C. When the peak temperature of the maximum endothermic peak is less than 60 ° C., the toner has poor blocking resistance, and conversely, when the peak temperature of the maximum endothermic peak exceeds 110 ° C., the fixability decreases.

  In order to obtain the desired transmittance α of the present invention, the release agent is 0.5 to 10 parts by weight, preferably 2 to 8 parts by weight per 100 parts by weight of the binder resin in the case of pulverized toner. 1 to 20 parts by mass, preferably 2 to 15 parts by mass, per 100 parts by mass of the binder resin.

A charge control agent can be added to the toner particles as necessary. Known charge control agents can be used, and examples thereof include aromatic carboxylic acid derivatives and aromatic carboxylic acid metal compounds. For example, the metal of the aromatic carboxylic acid metal 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⁺ , Ni ³⁺ , Ti ⁴⁺ , Zr ⁴⁺ and Si ³⁺ . Among these metals, Al ³⁺ and Cr ³⁺ are preferable, and Al ³⁺ is particularly preferable. In the present invention, an aluminum compound of di-tert-butylsalicylic acid is particularly preferable as the charge control agent.

  When the charge control agent is used in an amount of 0.1 to 10% by mass based on the mass of the toner, the initial fluctuation of the charge amount of the toner is small, and an absolute charge amount necessary for development is easily obtained. This is preferable since there is no decrease in image quality such as density reduction.

  The toner having a small particle diameter having a release agent described above has poor fluidity and environmental stability due to the presence of the release agent on the surface as compared with a toner having no release agent. Therefore, by externally adding silica particles (A) described in detail below, the above-mentioned problems can be eliminated and desired fluidity and environmental stability can be imparted to the toner.

  Further, by externally adding the silica particles (A), it is possible to reduce the cohesiveness of the silica particles, the adhesion to the photoreceptor, etc., which are always problematic when the silica particles are externally added.

The silica particles (A) in the present invention are silica particles (A) which are surface-treated by hydrolyzing at least a metal alkoxide represented by the following general formula (1).
M (OR) n (1)
(However, M represents a metal element, R represents an alkyl group, and n represents an integer. When n is 2 or more, R may be the same alkyl group or a plurality of alkyl groups having different carbon numbers and structures. Good.)

  The metal element (M) in the above general formula is not particularly limited, but Ti, Zr, Al, Sn, Zn, and Mg are suitable for controlling charging performance, and Ti and Zr have excellent fluidity imparting characteristics. Is particularly preferred. Further, the alkoxy group (RO) is not particularly limited, but methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, s-butoxy group, t-butoxy group and the like are common. Is preferred.

  The number average particle diameter of the silica particles (A) is preferably 0.005 μm to 0.100 μm. When the number average particle diameter is 0.005 μm or less, embedding in toner particles becomes remarkable during long-term use, and it becomes difficult to obtain a desired developer fluidity. When the number average particle diameter is 0.100 μm or more, it is difficult to obtain a desired developer fluidity. Further, embedding or adhesion to toner particles is weak, and the toner particles are easily detached from the surface, and even if the surface treatment is performed with metal alkoxide, adhesion to the photoreceptor or the like is likely to occur.

  Specific examples of the metal alkoxide used in the present invention include tetramethoxy titanium, tetraethoxy titanium, tetra-i-propoxy titanium, tetra-n-propoxy titanium, tetra-n-butoxy titanium, tetra-s-butoxy. Titanium, tetra-t-butoxy titanium, tetraethoxy zirconium, tetra-i-propoxy zirconium, tetra-n-butoxy zirconium, trimethoxy aluminum, triethoxy aluminum, tri-i-propoxy aluminum, tri-n-butoxy aluminum, tri -S-butoxyaluminum, tri-t-butoxyaluminum, mono-s-butoxydi-i-propylaluminum, dimethoxytin, diethoxytin, di-n-butoxytin, tetraethoxytin, tetra-i-propoxy , Tetra -n- butoxy tin, diethoxy zinc, magnesium methoxide, magnesium ethoxide, magnesium isopropoxide, and the like. Of these, tetra-i-propoxytitanium and tetra-n-butoxyzirconium are particularly suitable because they are readily available.

  In the present invention, one kind of such metal alkoxide can be used alone, or a plurality of kinds can be used sequentially or in combination. Metal alkoxides can be used as they are, but in consideration of viscosity, melting point, and other properties, they are appropriately diluted or dissolved in non-aqueous solvents such as alcohols, ethers, hydrocarbon solvents such as hexane and toluene, and silicone oils. Can also be used.

  The silica particles used in the present invention are both so-called dry process or dry silica particles called fumed silica produced by vapor phase oxidation of silicon halogen compounds, and so-called wet silica particles produced from water glass or the like. Can be used. Among these, fumed silica that can maintain a high fluidity imparting property is preferable.

  In this invention, a metal alkoxide is used as a raw material of the metal oxide adhering to the fumed silica surface. This is because the metal alkoxide can react with the surface silanol group on the fumed silica surface in the absence of physically adsorbed water and form a metal oxide layer finely and uniformly by hydrolysis reaction. By forming such a fine and uniform metal oxide layer, the fluidity imparting characteristics inherent to fumed silica can be maintained at a high level.

  Further, since the silica particles (A) are surface-treated with metal alkoxide, silica particles (A) are compared with silane coupling agents and surface-treated inorganic fine particles that are generally used in the past. The cohesiveness seen in many is weak, therefore there are few floating substances, such as a silica soul. As a result, it is possible to significantly reduce the adhesion of floating silica to the photoreceptor, which has been a problem in the past.

  Therefore, it is not preferable to use a metal halide represented by a metal chloride such as titanium tetrachloride or aluminum chloride in place of the metal alkoxide. The metal halide cannot adhere a sufficient amount of metal oxide to fumed silica due to its acidity, and halogen remains in the resulting surface-treated silica particles, resulting in unstable charge control.

  In addition, in order to increase the reactivity of the metal halide, a method of increasing the processing temperature to a high temperature of, for example, 500 ° C. If a method of adding a similar amount of water vapor is employed, the fluidity imparting properties of the surface-treated silica particles obtained are deteriorated, which is not preferable. This is because the metal halide is thermally decomposed at high temperature or hydrolyzed by water vapor before the fumed silica and the metal halide come into contact with each other. This is probably because a metal oxide layer cannot be formed.

  In the surface-treated silica particles (A) of the present invention, as a method for hydrolyzing a metal alkoxide to fumed silica, the surface treatment is performed by wet contact treatment, that is, fumed silica is a solvent such as water or an organic compound. A known method such as a method of dispersing in a metal and contacting with a metal alkoxide or a dry contact method described in detail below can be used.

  Among them, fumed silica and metal alkoxide are contact treated in a dry process to attach the metal alkoxide to the surface of fumed silica, and then contacted with water vapor to hydrolyze the metal alkoxide adhering to the surface, so that the surface treated silica It is preferred to obtain particles.

  That is, first, the adhesion of the metal alkoxide to the fumed silica, and the formation of the oxide layer of the metal by hydrolysis of the adhered metal alkoxide are all processed in a dry process, and the second, the fumed silica and the metal After achieving sufficient contact with the alkoxide, the two points are the order of hydrolyzing with water vapor, maintaining the fluidity imparting properties and adhesion to the photoreceptor of the surface-treated silica particles obtained. It is suitable and important for improvement.

  First, a description will be given of the point that all the first deposition of the metal alkoxide to the fumed silica and the formation of the oxide layer of the metal by hydrolysis of the deposited metal alkoxide are processed by a dry method.

  In the present invention, the dry-type contact treatment preferably used is not particularly limited to such a dry-type contact treatment method. Specifically, as described later, a method of bringing a metal alkoxide vapor into contact with fumed silica, fumed Examples thereof include a method in which a metal alkoxide stock solution or solution is sprayed onto silica for contact treatment.

  The surface-treated silica particles obtained by wet contact treatment, in which fumed silica is dispersed in a solvent such as water or an organic compound and contacted with the metal alkoxide, are obtained in the drying process for removing the solvent. The particles aggregate to form coarse particles, which may reduce the fluidity imparting characteristics inherent to fumed silica and the adhesion to the photoreceptor. Moreover, also from a viewpoint of productivity, the drying process which removes the said solvent after surface treatment, and a grinding | pulverization process following it are required, and productivity may be inferior.

  Specific methods for the contact treatment in a dry method include a method in which a metal alkoxide vapor transported by a carrier gas such as nitrogen is circulated to fumed silica in a stirred state or a fluidized bed, or a liquid metal alkoxide stock solution or solution There is a method of making a fine mist and spraying it on fumed silica under stirring. Among these, the spraying method is preferable because it can be easily carried out and the reaction efficiency between the metal alkoxide and fumed silica is increased.

  In particular, as described later, it is particularly preferable to carry out a contact treatment by spraying a stock solution or solution of metal alkoxide in a sealed state onto fumed silica heated to 100 to 400 ° C., preferably 120 to 350 ° C. .

  In the method of spraying the metal alkoxide described above, the metal alkoxide is a liquid stock solution, while a highly viscous liquid or solid solution is alcohol or ether, a hydrocarbon solvent such as hexane or toluene, silicone oil or the like. It is diluted or dissolved with a non-aqueous solvent, and supplied into the reactor in the form of a mist with a spray nozzle. By forming the mist, it is possible to avoid the formation of silica aggregates and to uniformly adhere the metal alkoxide to the fumed silica surface.

  The spray particle size is not particularly limited because it varies depending on the type and concentration of metal alkoxide, the viscosity of the liquid, and the form and size of the spray device and the size and shape of the reaction device, but is generally several μm to several hundred μm. The smaller one is preferable. As a spraying method, a commonly used spray nozzle, atomizer, or the like can be used. In particular, a one-fluid nozzle that is sprayed by pressurizing a liquid and passing it through a small-diameter orifice is opened uniformly in a sealed container. It is preferable that the metal alkoxide can be brought into contact with fumed silica.

  Next, the point that the order of performing the hydrolysis treatment with water vapor after the contact between the fumed silica and the metal alkoxide is important will be described.

  Before the contact between the fumed silica and the metal alkoxide, a condition in which water vapor exists in the reaction system, for example, a method of introducing the metal alkoxide after previously supplying adsorbed water to the fumed silica or adding water vapor to the reaction system Then, since a fine and uniform metal oxide layer cannot be formed and the fluidity imparting characteristics of fumed silica are deteriorated, it is not preferable. Under these conditions, before the silanol group on the fumed silica surface reacts with the metal alkoxide, it is hydrolyzed with adsorbed water or water vapor to form a fine and uniform metal oxide layer on the fumed silica surface. Estimated not possible.

  Therefore, it is possible to reduce the adsorbed water of fumed silica to less than 0.1%, preferably less than 0.05%, more preferably less than 0.01% in advance before the contact treatment with the metal alkoxide. It is preferable to increase The adsorbed water in this case generally refers to water called physical adsorbed water, and is water measured by weight loss due to drying at 105 ° C. for 2 hours. When the amount of adsorbed water of fumed silica is high, for example, 1% or more, the water vapor concentration in the reaction atmosphere increases during the contact treatment with the metal alkoxide, and the reaction atmosphere before the metal alkoxide contacts the fumed silica. As a result, it is difficult to achieve a fine and uniform metal oxide adhesion. As a method for lowering the adsorbed water level as described above, for example, put fumed silica as a raw material in a container heated to 100 to 400 ° C., preferably 120 to 350 ° C. The active gas can be achieved by sufficiently circulating, for example, over 2 hours.

  In addition, a preferred embodiment for contacting a metal alkoxide with fumed silica in a dry manner will be described.

  When the dry contact treatment between the metal alkoxide and fumed silica is carried out in a closed container, the fumed silica surface and the metal alkoxide sufficiently react with each other, and the silica surface is efficiently treated by the subsequent hydrolysis treatment. Is preferable.

  In addition, by carrying out the treatment at a temperature of 100 to 400 ° C., preferably 120 to 350 ° C., the reaction between fumed silica and metal alkoxide is promoted and works effectively for uniform adhesion of fine metal oxides. Thus, it is preferable because the rising property of charging and fluidity-imparting properties are improved and a solvent in which alcohol and metal alkoxide generated in the reaction are dissolved is easily removed from the system after adhesion. At a high temperature exceeding 400 ° C., the metal alkoxide is thermally decomposed before coming into contact with the fumed silica, which becomes a factor that inhibits the adhesion of a fine and uniform metal oxide.

  As the treatment method, for example, the original fumed silica is charged in a container heated to a predetermined temperature, and the inside of the container is replaced with an inert gas such as nitrogen while stirring, whereby the fumed silica is treated at the treatment temperature. After heating, the dry contact treatment is preferably started by sealing the reaction vessel and introducing the metal alkoxide using a spray nozzle or the like.

  Furthermore, the treatment time is not particularly limited because it varies depending on the properties of fumed silica, the type of metal alkoxide, the treatment temperature, and the like, but generally it is preferably 5 minutes to 3 hours.

  In the present invention, the fumed silica contacted with the metal alkoxide is brought into contact with water vapor to hydrolyze the metal alkoxide adhering to the surface to form a metal oxide coating layer on the fumed silica. Also in this case, as described above, when hydrolyzed by immersion in a solvent such as water or an organic compound containing water, that is, when hydrolyzed in a wet manner, the fluidity of the surface-treated silica obtained as described above is imparted. In some cases, characteristics and adhesion to the photoconductor may be deteriorated.

  Moreover, when not hydrolyzing, a large amount of undecomposed alkoxy groups in the metal alkoxide adhering to fumed silica remain, and the hydrophobizing efficiency in the next step tends to be lowered. When used as an external toner additive, the charging performance varies and becomes unstable depending on the environmental atmosphere such as humidity and temperature.

  As a specific hydrolysis method, fumed silica after dry-treating metal alkoxide is stirred or in a fluidized bed, water vapor is directly circulated, water vapor is adjusted by adjusting partial pressure with a carrier gas such as nitrogen. Examples thereof include a method of introducing water vapor and a method of introducing water vapor to the reactor and introducing water vapor. Hydrolysis with water vapor may be carried out in either a closed system or an open system. An acid-base catalyst such as ammonia may be added to the water vapor for the purpose of increasing the hydrolysis efficiency.

  The temperature of the hydrolysis treatment is not particularly limited as long as the fumed silica to which the metal alkoxide is adhered by water vapor can be treated in a dry manner, and generally, the condition is selected from the temperature range of 50 to 350 ° C. And it can be done. In particular, the treatment is preferably performed at a temperature equal to or higher than the dew point of water vapor.

  In the surface-treated silica particles (A) of the present invention, a metal oxide layer is formed on the surface by a series of dry production methods. The amount of the metal oxide layer is an element molar ratio, and M / Si (M is a metal element derived from a metal alkoxide) is 0.001 to 0.5, preferably 0.01 to 0.3. In order to give the surface-treated silica particles obtained with appropriate low chargeability and excellent charge rising characteristics, it is preferable.

  The amount of the metal (M) contained in the surface-treated silica particles was measured with a fluorescent X-ray analyzer ZSX100e manufactured by Rigaku Corporation, and was expressed as an M / Si element molar ratio.

  In the present invention, the surface-treated silica particles (A) obtained by a series of dry-type production methods have moderately low chargeability and excellent charge rise characteristics as described above, and are attached to the photoreceptor. Adhesion is weak and has excellent fluidity imparting properties.

  The reason why the silica particles (A) have reduced cohesiveness and excellent flowability imparting properties is not clear, but the present inventors presume as follows. That is, since the conventional manufacturing method is performed by dispersing fumed silica in a solvent, coarse agglomerated particles having a strong aggregating force are formed in the solvent removal process and adhere to the photoreceptor. Further, when this is mixed with the toner, the dispersion is insufficient, and it is considered that a flow defect is caused. On the other hand, the surface-treated silica particles obtained through the dry production method of the present invention do not produce coarse agglomerated particles with strong agglomeration force, so that the fluidity imparted by fumed silica is inherent. It is presumed that the characteristics and adhesion to the photoreceptor are reduced and maintained.

  As a result of observing the surface-treated silica particles (A) of the present invention with a transmission electron microscope (TEM) at a magnification of 200,000, the metal oxide adhered to fumed silica was a lump whose major axis exceeded 20 nm, or No particulate matter was seen. In this observation method, it is difficult to discriminate a metal oxide smaller than 1 nm, and therefore it has not been possible to determine whether the metal oxide adhering to fumed silica is particulate or layered. Moreover, as a result of mapping the Si element by TEM-EELS and the metal element of the attached metal alkoxide, it was confirmed that the distribution of both elements was not biased and the metal oxide was uniformly attached to the fumed silica. . That is, the fact that the metal oxide is finely and uniformly attached is a feature of the surface-treated silica particles of the present invention, and has excellent charge rising characteristics and flowability that could not be achieved with conventional silica particles. It is considered that favorable effects such as property imparting characteristics are exhibited.

  Therefore, it is a feature of the surface-treated silica particles of the present invention that the metal oxide adhered to fumed silica does not have a coarse portion exceeding 20 nm, preferably a large lump exceeding 10 nm. This is a preferable property for exhibiting excellent effects such as imparting characteristics.

  In the present invention, the silica particles (A) thus produced may be hydrophobized.

  As in the above, the hydrophobization treatment in the dry method is a method of treating the surface-treated silica particles with a hydrophobizing agent in a dry manner. The processing method such as a processing method is not particularly limited, and any known method can be used without any problem.

  Among them, the dry method maintains moderate low chargeability and excellent charge rise characteristics obtained by a series of metal alkoxide dry production methods, and has low cohesiveness and adheres to photoreceptors, etc. Is preferable in that it has excellent fluidity-imparting characteristics and adhesion to a photoreceptor.

  Examples of the dry method include a method of treating the surface-treated silica particles by spraying a hydrophobizing agent with stirring, and a method of introducing hydrophobizing agent vapor into the fluidized bed or the surface-treated silica particles under stirring.

  As the hydrophobizing agent, a known treating agent can be used without any limitation. Specifically, as a silylating agent, chlorosilanes such as methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, t-butyldimethylchlorosilane, vinyltrichlorosilane, tetramethoxysilane, methyl Trimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, o-methylphenyltrimethoxysilane, p-methylphenyltrimethoxysilane, n-butyltrimethoxysilane, i-butyltrimethoxysilane, hexyltrimethoxy Silane, octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyl Diethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, i-butyltriethoxysilane, decyltriethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ- (2-aminoethyl) Alkoxysilanes such as aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, hexamethyldisilazane, hexaethyldisilazane, hexapropyldisilazane, hex Buchirujishirazan, hexa pliers distearate disilazane, hexa hexyl disilazane, hexa cyclohexyl disilazane, there hexaphenyl disilazane, divinyl tetramethyl disilazane, silazanes such as dimethyl tetra-vinyl disilazane and the like. Also, dimethyl silicone oil, methyl hydrogen silicone oil, methyl phenyl silicone oil, alkyl modified silicone oil, chloroalkyl modified silicone oil, chlorophenyl modified silicone oil, fatty acid modified silicone oil, polyether modified silicone oil, alkoxy modified silicone oil, Silicone oils such as diol-modified silicone oil, amino-modified silicone oil, fluorine-modified silicone oil, and terminal-reactive silicone oil, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, hexamethyldisiloxane Siloxanes such as octamethyltrisiloxane are also preferred as the hydrophobizing agent. Furthermore, fatty acids and their metal salts include undecyl acid, lauric acid, tridecyl acid, dodecyl acid, myristic acid, palmitic acid, pentadecyl acid, stearic acid, heptadecyl acid, arachidic acid, montanic acid, oleic acid, linoleic acid, arachidonic acid Long metal fatty acids such as zinc, iron, magnesium, aluminum, calcium, sodium, lithium and other metals are effective as hydrophobizing agents. Of these, silylating agents are the most common, and alkoxysilanes and silazanes are preferable because they can be easily treated. In the present invention, one type of such a hydrophobizing agent is used alone, or in the case of two or more types, they are mixed, or the surface treatment is sequentially carried out to obtain the required hydrophobicity according to the application. Can be achieved.

  In the present invention, the silica particles (A) have an Mw value (degree of methanol hydrophobization) of 50% to 80% for the purpose of reducing desired properties, that is, environmental stability and adhesion to the photoreceptor. Preferably there is.

(Measurement of hydrophobicity (Mw value))
0.2 g of hydrophobized silica particles was added to 50 ml of water in a 250 ml beaker and stirred with a magnetic stirrer. To this was added methanol using a burette, and titration was performed with the end point when the entire amount of hydrophobized silica particles was wetted and suspended in the solvent in the beaker. At this time, the tube was introduced into the solution by a tube so that the sample did not directly touch the sample. The value of volume% of methanol in the methanol-water mixed solvent at the end point was defined as the degree of hydrophobicity (M value).

  In addition, the method of performing the hydrophobization treatment before the formation of the metal oxide layer cannot form the metal oxide layer and cannot obtain the hydrophobized silica particles of the present invention.

  The addition amount of the silica particles (A) of the present invention to the toner particles is not particularly limited as long as the obtained toner has desired characteristics, but is usually 0.05 to 5% by mass, preferably 0. It is preferably 1 to 4% by mass, and can be externally added to the toner by a known method.

  Next, the inorganic fine particles (B) and inorganic fine particles (C) used in the present invention will be described.

  As the inorganic fine particles (B) and inorganic fine particles (C) of the present invention, for example, known inorganic compounds such as silica, alumina and titanium oxide can be used, and at least of the inorganic fine particles (B) and the inorganic fine particles (C). One type is silica particles that hydrolyze metal alkoxide to surface-treat. The surface treatment of the silica particles by hydrolyzing the metal alkoxide is not particularly limited, and a known method can be used, but the surface of the silica particles (A) can be used from the viewpoint of charging uniformity and fluidity. It is preferable to carry out the processing method. The inorganic fine particles (B) are particularly preferably silica particles (A).

  The toner of the present invention contains inorganic fine particles (C) having a number average particle size of 0.06 to 0.30 μm in order to further improve transferability. The number average particle diameter is determined from an electron micrograph, and the number average particle diameter of the inorganic fine particles (B) is preferably 0.06 to 0.30 μm, more preferably 0.07 to 0.20 μm. More preferably, it is 0.08 to 0.15 μm. The number average particle diameter of the inorganic fine particles (B) is preferably smaller than the number average particle diameter of the inorganic fine particles (C). When the average particle size of the inorganic fine particles (C) is smaller than 0.06 μm and / or smaller than the inorganic fine particles (B), the function as a spacer is weak and the contribution to the improvement of transferability is small. Or it may become easy to adhere and fuse to a photoreceptor or the like. On the other hand, when it is larger than 0.3 μm, the toner is easily detached from the toner, and it is difficult to stably adhere to the surface of the toner base particles, and the transfer efficiency is lowered. In addition, the toner may be detached from the toner during development to contaminate the periphery of the developing device, or the detached fine powder may adhere to and fuse to the photosensitive member, intermediate transfer member, carrier, or the like, causing image defects.

  In the present invention, the inorganic fine particles (C) are not particularly limited in composition, such as silica, alumina, and titanium oxide, as long as the number average particle diameter is 0.06 to 0.30 μm. For example, in the case of silica, those produced by a conventionally known technique obtained by any method such as a gas phase decomposition method, a combustion method, and a deflagration method can be used. In particular, the number produced by a known sol-gel method in which the solvent is removed from the silica sol suspension obtained by hydrolyzing and condensing the alkoxysilane with a catalyst in an organic solvent in which water is present, and then dried to form particles. Particles having an average particle size of 0.06 to 0.30 μm are preferred. Further, the inorganic fine particles (B) and (C) may be used after being hydrophobized, and as the hydrophobizing agent, a known treating agent exemplified in the hydrophobizing treatment of the silica particles (A) can be used. However, a silane coupling agent or silicone oil can be preferably used. When the surface treatment is performed with a metal alkoxide, the above silane coupling agent, silicone oil or the like, it is preferable to follow the method described above for the silica particles (A).

  The amount thereof is 1 to 40 parts by mass, preferably 2 to 35 parts by mass with respect to 100 parts by mass of silica. When the treatment amount is 1 to 40 parts by mass, moisture resistance is improved and aggregates are hardly generated.

  In the toner of the present invention, the amount of the inorganic fine particles (C) added is 0.3 to 5.0 parts by mass, more preferably 0.5 to 3.0 parts by mass with respect to 100 parts by mass of the toner base particles. .

  By using the inorganic fine particles (C) together with the inorganic fine particles (B), the fluidity-imparting effect of the inorganic fine particles (B), the environmental stability, the charging stability, the adhesion to the photoconductor, etc. are reduced. ) Transferability synergistically improved, charging was stable even under long-term use, and fluctuations in transfer efficiency were reduced.

  In addition, the inorganic fine particles (C) have a spherical shape to a substantially spherical shape, have a small contact area with the toner base, and can move on the toner surface and localize to a portion where friction is expected to be large after long-term use. This was confirmed from a toner electron microscope image after long-term use. However, in order to maintain stable transferability, it is desirable that the inorganic fine particles (C) be uniformly deposited on the surface of the toner and remain at the initial position even under long-term use. By adhering the inorganic fine particles (B) to the surface of the toner, the inorganic fine particles (B) become minute irregularities on the toner surface, and receive moderate friction against particles having a size of about the inorganic fine particles (C). This is considered to be the effect of preventing the localization of (C).

  In the toner for developing an electrostatic latent image of the present invention, an inorganic compound having a small particle diameter can be used together with the inorganic fine particles (B) and the inorganic fine particles (C) as an external additive. As the inorganic compound having a small particle diameter, known compounds can be used, and examples thereof include silica, alumina, titanium oxide, calcium carbonate, magnesium carbonate, calcium phosphate, cerium oxide and the like. Depending on the purpose, the surface of these inorganic fine particles may be subjected to a known surface treatment such as a hydrophobic treatment. In particular, the layer orientation titanium oxide does not affect the transparency, and provides a developer with excellent chargeability, environmental stability, fluidity, caking resistance, stable negative chargeability, and stable image quality maintenance. can do. The inorganic compound having a small particle size preferably has a volume average particle size of 80 nm or less, and more preferably 50 nm or less.

  The toner described above can be suitably used for nonmagnetic one-component development.

<Regarding Two-Component Developer Developer Having Toner of the Present Invention>
When the toner of the present invention is used for a two-component developer, the toner is used by mixing with a magnetic carrier. As the magnetic carrier, known magnetic carriers such as magnetic particles themselves, coated carriers in which magnetic particles are coated with a resin, and magnetic material-dispersed resin carriers in which magnetic particles are dispersed in resin particles can be used. Examples of magnetic particles include surface oxidized or unoxidized iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, chromium, rare earth metal particles, alloy particles thereof, oxide particles, ferrite, etc. Can be used.

  The coated carrier obtained by coating the surface of the magnetic carrier particles with a resin is particularly preferable in a developing method in which an AC bias is applied to the developing sleeve. As a coating method, a method in which a coating solution prepared by dissolving or suspending a coating material such as a resin in a solvent is adhered to the surface of the magnetic carrier core particle, and a method in which the magnetic carrier core particle and the coating material are mixed with powder. A conventionally known method can be applied.

  Examples of the coating material on the surface of the magnetic carrier core particle include silicone resin, polyester resin, styrene resin, acrylic resin, polyamide, polyvinyl butyral, and aminoacrylate resin. These are used alone or in plural. The treatment amount of the coating material is preferably 0.1 to 30% by mass (preferably 0.5 to 20% by mass) with respect to the carrier core particles. The volume-based 50% particle size (D50) of these magnetic carrier core particles is 10 to 100 μm, preferably 20 to 70 μm.

  The volume-based 50% particle size of the present invention was measured with a laser diffraction particle size distribution meter (manufactured by Horiba, Ltd.).

  When a two-component developer is prepared by mixing the toner of the present invention and a magnetic carrier, the mixing ratio is usually 2 to 15% by mass, preferably 4 to 13% by mass, as the toner concentration in the developer. Good results are obtained. If the toner concentration is less than 2% by mass, the image density tends to decrease, and if it exceeds 15% by mass, fogging or in-machine scattering tends to occur.

<Regarding the Toner Production Method of the Present Invention>
The toner used in the present invention is a toner particle having at least a binder resin, a colorant and a release agent, and a toner having at least silica particles (A), and has a transmittance in MeOH and other preferable forms. If it is a thing of the range which is satisfied, it will not be specifically limited by a manufacturing method, A well-known method can be used.

  For example, the toner is produced by kneading, pulverizing, and classifying a binder resin, a colorant, a release agent, and, if necessary, a charge control agent. Method of changing shape by force or thermal energy, emulsion polymerization of polymerizable monomer of binder resin, dispersion of formed dispersion, colorant, release agent, and charge control agent as required Emulsion polymerization agglomeration method to obtain toner particles by mixing and agglomerating and heat fusing the liquid, polymerizable monomer and colorant, release agent, and charge control agent if necessary Suspension polymerization method in which the solution is suspended in an aqueous solvent for polymerization, a binder resin and a colorant, a release agent, and if necessary, a solution such as a charge control agent is suspended in an aqueous solvent for granulation A suspension method or the like can be used. In addition, a manufacturing method may be performed in which the toner obtained by the above method is used as a core, and agglomerated particles are further adhered and heat-fused to give a core-shell structure.

  As the toner used in the present invention, a toner that is spheroidized in the manufacturing process or in the post-manufacturing process is preferably used.

  Toner that has been spheroidized in the post-manufacturing process is, for example, a pulverized toner produced by mixing, stirring, pulverizing and classifying a resin, colorant, or the like that is a constituent material of the toner. The toner that is made into a spherical shape in the production process is a toner produced by a polymerization method such as a dispersion polymerization method, a suspension polymerization method, or an emulsion polymerization method.

  In particular, in the toner having the release agent of the present invention, as a method for obtaining the desired transmittance and circularity in 45% MeOH, the method for producing a pulverized toner described in detail below is suitable.

  First, in the raw material mixing step, as a toner internal additive, at least a binder resin, a colorant, and a release agent are weighed and mixed and mixed. Examples of the mixing device include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, and a Nauter mixer.

  Further, the toner raw materials blended and mixed as described above are melt-kneaded to melt the binder resin, and the colorant and the like are dispersed therein. In the melt-kneading step, for example, a batch kneader such as a pressure kneader or a Banbury mixer, or a continuous kneader can be used. In recent years, single-screw or twin-screw extruders have become mainstream due to the advantage of being capable of continuous production. For example, KTK type twin screw extruder manufactured by Kobe Steel, TEM type twin screw extruder manufactured by Toshiba Machine Co., Ltd. In general, a twin-screw extruder manufactured by Kay Sea Kay, a co-kneader manufactured by Buss, or the like is used. Furthermore, the colored resin composition obtained by melt-kneading the toner raw material is rolled by a two-roll roll after melt-kneading, and then cooled through a cooling step of cooling by water cooling or the like.

  In general, the cooled colored resin composition obtained above is then pulverized to a desired particle size in a pulverization step. In the pulverization step, first, coarse pulverization is performed with a crusher, a hammer mill, a feather mill or the like, and further, pulverization is performed with a kryptron system manufactured by Kawasaki Heavy Industries, Ltd., a super rotor manufactured by Nisshin Engineering Co., Ltd. or the like. After that, if necessary, classification is performed using a classifier such as an inertia class elbow jet (manufactured by Nippon Steel & Mining Co., Ltd.), centrifugal class turbo plex (manufactured by Hosokawa Micron Co., Ltd.), and the weight average particle size A classified product of 4 to 11 μm is obtained.

  If necessary, surface modification (= spheroidization treatment) can be performed in the surface modification process. For example, a hybridization system manufactured by Nara Machinery Co., Ltd. or a mechano-fusion system manufactured by Hosokawa Micron Co., Ltd. is used as a classified product. You can also.

  However, as a preferable production process of the toner of the present invention, mechanical pulverization is not used in the pulverization process, and the surface using the classification and mechanical impact force shown in FIGS. 1 and 2 is used after pulverization with an air jet pulverizer. It is to obtain a classified product having a weight average particle diameter of 4 to 11 μm using the apparatus A that simultaneously performs the reforming treatment.

  In addition, you may use sieving machines, such as a high volta of a wind-type sieve (made by Shin Tokyo Machine Co., Ltd.) as needed. Furthermore, when processing with an external additive, a high-speed stirrer that gives a shearing force to powder such as a Henschel mixer or a super mixer is blended with a predetermined amount of classified toner and various known external additives. Can be used as The toner of the present invention can be obtained by stirring and mixing.

  Here, the apparatus A used in the present invention will be described in detail below.

  The batch type surface reforming apparatus shown in FIG. 1 includes a cylindrical main body casing 30, a top plate 43 installed so as to be openable and closable at the upper part of the main body casing; a fine powder discharge section 44 having a fine powder discharge casing and a fine powder discharge pipe; A cooling jacket 31 through which cooling water or antifreeze can be passed; a plurality of square disks 33 on the upper surface, which are attached to the central rotating shaft in the main body casing 30 as surface modification means, in a predetermined direction Dispersion rotor 32, which is a disk-like rotating body that rotates at high speed; liner 34 that is fixedly arranged around dispersion rotor 32 at a constant interval and that has a large number of grooves on the surface facing dispersion rotor 32 A classification rotor 35 for continuously removing fine powder and ultrafine powder having a predetermined particle size or less in the finely pulverized product; cold air inlet 4 for introducing cold air into the main body casing 30; A charging pipe having a raw material charging port 37 and a raw material supplying port 39 formed on the side surface of the main body casing 30 for introducing finely pulverized material (raw material); discharging toner particles after the surface modification treatment to the outside of the main body casing 30; A product discharge pipe having a product discharge port 40 and a product extraction port 42 for opening and closing; an openable and closable raw material installed between the raw material input port 37 and the raw material supply port 39 so that the surface modification time can be freely adjusted A supply valve 38; and a product discharge valve 41 installed between the product discharge port 40 and the product extraction port 42.

  The surface of the liner 34 has grooves as shown in FIGS. 6A and 6B, which is preferable for efficiently modifying the surface of the toner particles. As shown in FIGS. 3A and 3B, the number of the rectangular disks 33 is preferably an even number in consideration of the rotation balance. Illustrations of the rectangular disk 33 are shown in FIGS.

  The classification rotor 35 shown in FIGS. 1, 2 and 7 is preferably rotated in the same direction as the rotation direction of the dispersion rotor 32 in order to increase the efficiency of classification and the efficiency of surface modification of toner particles. The fine powder discharge pipe has a fine powder discharge port 45 for discharging fine powder and ultrafine powder removed by the classification rotor 35 to the outside of the apparatus.

  The surface modification apparatus further includes a cylindrical guide ring 36 as a guide means having an axis perpendicular to the top plate 43 in the main body casing 30 as shown in FIGS. 4 (A) and 4 (B). Have. The upper end of the guide ring 36 is provided at a predetermined distance from the top plate, and the guide ring is fixed to the main body casing 30 by a support so as to cover at least a part of the classification rotor 36. The lower end of the guide ring 36 is provided at a predetermined distance from the rectangular disk 33 of the dispersion rotor 32. In the surface modification apparatus, a space between the classification rotor 35 and the dispersion rotor 32 is guided into a first space 47 outside the guide ring 36 and a second space 48 inside the guide ring 36. Divided by 36. The first space 47 is a space for guiding the finely pulverized product and the surface-modified particles to the classification rotor 35, and the second space guides the finely pulverized product and the surface-modified particles to the dispersion rotor. It is a space for. A gap between the plurality of rectangular disks 33 installed on the dispersion rotor 32 and the liner 34 is a surface modification zone 49, and the classification rotor 35 and a peripheral portion of the classification rotor 35 are classification zones 50. .

  As shown in FIG. 7, the finely pulverized product introduced into the raw material hopper 380 passes through the quantitative feeder 315, passes through the raw material input port 37 of the input pipe, passes through the raw material supply valve 38, and enters the apparatus from the raw material supply port 39. Supplied. In the surface reforming apparatus, the cold air generated by the cold air generating means 319 is supplied into the main body casing from the cold air inlet 46, and further, the cold water from the cold water generating means 320 is supplied to the cold water jacket 31 to Adjust the temperature to a predetermined temperature. The supplied finely pulverized product swirls in the first space 47 outside the cylindrical guide ring 36 by the swirl flow formed by the suction air volume by the blower 364, the rotation of the dispersion rotor 32 and the rotation of the classification rotor 35. However, the classification process is performed by reaching the classification zone 50 in the vicinity of the classification rotor 35. The direction of the swirl flow formed in the main body casing 30 is the same as the rotation direction of the dispersion rotor 32 and the classification rotor 35.

  The fine powder and super fine powder to be removed by the classification rotor 35 are sucked from the slit of the classification rotor 35 (see FIG. 2) by the suction force of the blower 364 and are passed through the fine powder discharge port 45 and the cyclone inlet 359 of the fine powder discharge pipe. 369 and bug 362. The finely pulverized product from which fine powder and ultrafine powder have been removed reaches the surface modification zone 49 in the vicinity of the dispersion rotor 32 via the second space 48, and the square disk 33 (hammer) provided in the dispersion rotor 32 and the main body. The surface modification treatment of the particles is performed by the liner 34 provided in the casing 30. The particles subjected to the surface modification reach the classification rotor 35 again while turning along the guide ring 36, and fine particles and ultrafine particles are removed from the surface-modified particles by the classification rotor 35 classification. . After performing the treatment for a predetermined time, the discharge valve 41 is opened, and the surface-modified toner particles from which fine powder having a predetermined particle diameter or less and ultrafine powder are removed are taken out from the surface reforming apparatus.

  The toner particles adjusted to a predetermined weight average diameter, adjusted to a predetermined particle size distribution, and further surface-modified to a predetermined circularity are transferred to the external additive adding step by the toner particle transport means 321. .

  The surface reforming apparatus used in the present invention includes a dispersion rotor 32, a finely pulverized product (raw material) input unit 39, a classification rotor 35, and a fine powder discharge unit from the lower side in the vertical direction. Therefore, normally, the drive portion (motor or the like) of the classification rotor 35 is provided further above the classification rotor 35, and the drive portion of the dispersion rotor 32 is provided further below the dispersion rotor 32. The surface reforming apparatus used in the present invention is a finely pulverized product (raw material) classified into a classification rotor, such as a TSP classifier (manufactured by Hosokawa Micron Corporation) having only a classification rotor 35 described in JP-A-2001-259451. It is difficult to supply from the vertically upward direction of 35.

  In the present invention, it is preferable that the tip peripheral speed of the classification rotor 35 having the largest diameter is 30 to 120 m / sec. The tip circumferential speed of the classification rotor is more preferably 50 to 115 m / sec, and further preferably 70 to 110 m / sec. If it is slower than 30 m / sec, the classification yield tends to decrease, and the amount of ultrafine powder tends to increase in the toner particles. If it is faster than 120 m / sec, the problem of increased vibration of the device is likely to occur.

  Furthermore, it is preferable that the tip peripheral speed of the portion with the largest diameter of the dispersion rotor 32 is 20 to 150 m / sec. The tip peripheral speed of the dispersion rotor 32 is more preferably 40 to 140 m / sec, and further preferably 50 to 130 m / sec. When it is slower than 20 m / sec, it is difficult to obtain surface-modified particles having sufficient circularity, which is not preferable. When the speed is higher than 150 m / sec, particles are likely to be fixed inside the apparatus due to the temperature rise inside the apparatus, and the classification yield of the toner particles is likely to be lowered. By setting the tip peripheral speeds of the classification rotor 35 and the dispersion rotor 32 in the above range, the classification yield of the toner particles can be improved and the surface modification of the particles can be performed efficiently.

  In the toner production method of the present invention, it is preferable that the finely pulverized product (raw material) supplied to the raw material inlet 37 of the surface reformer has a specific particle size distribution. Furthermore, it is preferable that the amount of ultra fine powder of toner particles (surface modified particles) after being processed by the surface modifying apparatus is controlled to a predetermined amount. In the present invention, the weight average particle size of the finely pulverized product is 3.0 to 9.0 μm, and the proportion of particles having a particle size of 4.00 μm or less is 50 to 80% by number. The ratio of particles (fine powder) having an average particle diameter of 3.0 to 11.0 μm and a particle diameter of 4.00 μm or less is 5 to 40% by number, and further measured with a flow particle image measuring device for toner particles. In the particle size distribution based on the number of particles having an equivalent circle diameter of 0.6 μm or more and 400 μm or less, the ratio of toner particles having an equivalent circle diameter of 0.6 μm or more and less than 3 μm (ultra fine powder) is 0 to 15% by number. Is preferred.

  The particle size distribution of the finely pulverized product affects the classification efficiency. When there are many fine particles in the finely pulverized product, the classification time becomes long, and even particles that do not need to be classified and removed are removed by classification, which may cause a reduction in classification yield. Furthermore, the cohesiveness of the finely pulverized product becomes high when classification is performed, and it may be difficult to remove the ultrafine powder that should be removed from the toner particles, and the resulting toner is likely to be fogged.

  Therefore, when the weight average particle size of the finely pulverized product is smaller than 3.0 μm, the cohesiveness between the particles becomes high and efficient classification may be difficult. On the other hand, when the weight average particle size of the finely pulverized product is larger than 9.0 μm, it is not preferable for the obtained toner to form a clear image quality. On the other hand, when the ratio of particles having a particle diameter of 4.00 μm or less is less than 50% by number, it is difficult to form a clear image with the obtained toner. On the other hand, when the proportion of particles having a particle size of 4.00 μm or less is more than 80% by number, the cohesiveness of the finely pulverized product becomes high and it is difficult to obtain a good classification yield. Furthermore, when the ratio of particles having a particle size of 4.00 μm or less is more than 80% by number, the ultra fine powder in the finely pulverized product tends to increase, which is not preferable. The proportion of particles having a particle size of 4.00 μm or less in the finely pulverized product is preferably 55 to 75% by number.

  In the particle size distribution based on the number of particles having an equivalent circle diameter of 0.6 μm or more and 400 μm or less, which is measured by a flow type particle image measuring apparatus for toner particles processed by the surface modification device, the equivalent circle diameter is 0. It is preferable to control the ratio of toner particles (ultra fine powder) of 6 μm or more and less than 3 μm to a range of 0 to 15% by number. When the ratio of toner particles having an equivalent circle diameter of 0.6 μm or more and less than 3 μm is more than 15% by number, the obtained toner is not preferable because fogging phenomenon easily occurs. The ratio of toner particles having an equivalent circle diameter of 0.6 μm or more and less than 3 μm is more preferably 13% by number or less.

  The toner of the present invention can be used in any system. For example, a developer for a high-speed system, a developer for oilless fixing, a developer for a cleaner system, and a carrier in a developing device that has deteriorated due to long-term use are sequentially collected. The present invention can be applied to a known developing method such as a developer for a developing system that replenishes a fresh carrier. In particular, the toner of the present invention has very good transfer efficiency and reduces the adhesion of external additives to the photoconductor. Therefore, the toner of the present invention is suitable for an image forming apparatus having an intermediate transfer body and an image forming apparatus having a cleaner system. Can be suitably used.

  Specific examples of the present invention will be described below, but the present invention is not limited to these examples.

(Example of hybrid resin production)
As a monomer for forming a vinyl polymer unit, 2.0 mol of styrene, 0.21 mol of 2-ethylhexyl acrylate, 0.14 mol of fumaric acid, 0.03 mol of a dimer of α-methylstyrene, and dicumyl peroxide as a polymerization initiator 0.05 mol is put into the dropping funnel. Moreover, 7.0 mol of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis (4) are used as monomers for forming the polyester unit. -Hydroxyphenyl) propane 3.0 mol, terephthalic acid 3.0 mol, trimellitic anhydride 1.9 mol, fumaric acid 5.0 mol and 0.2 g of dibutyltin oxide as a catalyst are placed in a 4-liter 4-neck flask made of glass. A thermometer, a stirring bar, a condenser and a nitrogen introduction tube were attached and placed in a mantle heater. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the vinyl monomer and the polymerization initiator were dropped from the previous dropping funnel over 4 hours while stirring at a temperature of 145 ° C. Next, the temperature was raised to 200 ° C. and reacted for 4 hours to obtain a hybrid resin. The results of molecular weight measurement by GPC are shown in Table 1.

(Example of polyester resin production)
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, 1.4 mol of trimellitic anhydride, 2.4 mol of fumaric acid and 0.12 g of dibutyltin oxide are placed in a 4-liter glass four-necked flask, a thermometer, a stirring rod, a condenser and a nitrogen inlet tube And placed in the mantle heater. Under a nitrogen atmosphere, reaction was performed at 215 ° C. for 5 hours to obtain a polyester resin. The results of molecular weight measurement by GPC are shown in Table 1.

[Production Example of Silica Particle A]
(Silica particles a)
100 parts by mass of fumed silica having a specific surface area of 200 m ² / g was placed in a mixer, stirred, and replaced with a nitrogen atmosphere, and simultaneously heated to 250 ° C. Then, 250 degreeC was hold | maintained for 2 hours, stirring and circulation of nitrogen gas. By this operation, the adsorbed water of fumed silica became less than 0.05%. The mixer was sealed, and 30 parts by mass of tetra-i-propoxytitanium was sprayed with a one-fluid nozzle. Stirring was continued for 60 minutes after spraying. Next, the mixer was opened, and hydrolysis was carried out by passing 115 parts by mass of steam over 60 minutes while maintaining stirring at 250 ° C.

  50 parts by mass of the obtained metal alkoxide surface-treated silica particles were placed in a high-speed mixer and stirred, and replaced with a nitrogen atmosphere and simultaneously heated to 250 ° C. After replacing 60% in the mixer with water vapor, the mixer was sealed, 60 parts by mass of octyltrimethoxysilane was sprayed, and the mixture was stirred as it was for 30 minutes to carry out a hydrophobization treatment to obtain silica particles a.

  Various physical properties of the silica particles a are as shown in Table 2.

(Silica particles b to h)
Except having changed the element molar ratio (M / Si) of metal alkoxide, it carried out by the manufacturing method similar to the silica particle a, and obtained silica particle bh. Various physical properties of the silica particles b to h are as shown in Table 2.

(Silica particles i)
Except that the surface treatment with octyltrimethoxysilane was not carried out, it was carried out in the same manner as the production method of the silica particles a to obtain silica particles i. Various physical properties of the obtained silica particles i are as shown in Table 2.

(Silica particles j)
Silica particles j were obtained in the same manner as the production method of silica particles a except that water vapor was not used and nitrogen gas was circulated instead and hydrolysis was not performed. Various physical properties of the obtained silica particles j are shown in Table 2.

(Silica particles km)
Except for changing the particle size of the fumed silica and changing the amount of the metal alkoxide, the production method was the same as that for the silica particles a to obtain silica particles k to m. Various physical properties of the silica particles k to m are as shown in Table 2.

[Silica particle n]
50 parts by mass of fumed silica having a specific surface area of 200 m ² / g was placed in a high-speed mixer, stirred, and replaced with a nitrogen atmosphere, and simultaneously heated to 250 ° C. After 60% of the mixer was replaced with water vapor, the mixer was sealed, sprayed with 60 parts by mass of octyltrimethoxysilane and stirred for 30 minutes, and then 60 parts by mass of dimethyl silicone oil was added in the same manner. Hydrophobization treatment was performed to obtain silica particles n.

  Various physical properties of the silica particles n are as shown in Table 2.

[Production example of inorganic fine particles]
(Inorganic fine particles 1-7)
Using the silica particles obtained by the sol-gel method with the particle sizes shown in Table 2, surface treatment was performed in the same manner as the silica particles a using the treatment agent and the treatment amount in Table 2 (amount based on 100 parts by mass of the inorganic fine particles). Inorganic fine particles 1 to 7 were obtained. Various physical properties of the inorganic fine particles 1 to 7 are as shown in Table 3.

(Inorganic fine particle 8)
Using the silica particles obtained by the sol-gel method with the particle sizes shown in Table 2, the surface treatment with tetra-i-proxy titanium is not performed in the production method of the inorganic fine particles 1, and only octyltrimethoxysilane is formulated in Table 2. Surface treatment was performed in an amount to obtain inorganic fine particles 8. Various physical properties of the inorganic fine particles 8 are as shown in Table 3.

  Next, Table 4 shows the wax used in this example.

<Example 1>
Toner 1 was prepared by the following method.

Hybrid resin 100 parts by mass Wax A 5 parts by mass 1,4-di-t-butylsalicylic acid aluminum compound 2 parts by mass Cyan pigment (Pigment Blue 15: 3) 5 parts by mass After mixing, the mixture was melt-kneaded with a twin-screw extrusion kneader, cooled and roughly pulverized to about 1 to 2 mm using a hammer mill, and then finely pulverized to a particle size of 20 μm or less with an air jet type pulverizer. Further, the obtained finely pulverized product was pulverized by an apparatus that simultaneously performs the classification shown in FIG. 1 and the surface modification treatment using mechanical impact force to obtain cyan toner particles shown in Table 5.

  To 100 parts by mass of the cyan toner particles, 0.7 parts by mass of silica particles a and 0.5 parts by mass of titanium oxide fine particles having a primary particle diameter of 50 nm surface-treated with isobutyltrimethoxysilane were externally added using a Henschel mixer, and cyan toner A. The cyan toner A had a weight average particle diameter of 6.0 μm, a transmittance B in an aqueous solution of 45% by volume of methanol: 40%, and an average circularity B: 0.933.

  Further, cyan toner 1 and magnetic ferrite carrier particles (volume average particle diameter 45 μm: Mn—Mg ferrite) surface-coated with a silicone resin are mixed so that the toner concentration becomes 8.0% by mass, and a two-component system. Cyan developer 1 was obtained.

  Using the obtained toner and two-component developer, a commercially available copying machine iRC3200 (manufactured by Canon Inc .: image forming apparatus of cleanerless system having an intermediate transfer member), 50,000 single-color original images of A4 black and DUTY 5% are obtained. Images were printed out and evaluated for transfer efficiency, fog, image density stability, image density uniformity / image quality, and image defects due to inorganic fine particles adhering to the photoreceptor. The evaluation environment was 30.0 ° C./95% RH (H / H) and 25.0 ° C./15% RH (N / L). The results are shown in the table. Each measurement condition and evaluation criteria are shown below. Table 7 shows good results for image density stability, transfer efficiency, fogging, image uniformity / image quality, and image defects caused by inorganic fine particles adhering to the photoreceptor even during and after 50,000 sheets have been used. It was.

  The measurement method of the triboelectric charge amount used in this example and the evaluation criteria for each evaluation are as follows.

<Transfer efficiency>
Using a chart that can form a plurality of circle or band images, D1 is the density of the remaining transfer on the drum and taped on the paper, and D2 is the density of the tape transferred onto the paper, and the following formula: calculate.
Transfer efficiency (%) = D2 / (D1 + D2) × 100
A: 96% or more.
B: 93% or more and less than 96%.
C: 90% or more and less than 93%.
D: 87% or more and less than 90%.
E: Less than 87%.

<Fog>
With regard to fog, after the completion of 50,000-sheet printing, a reflection densitometer (densitometer TC6MC: Tokyo Denshoku Technology Center) was used to measure the reflection density of white paper and the non-image of the paper printed by a copier. The reflection density of each part was measured, and the difference between the reflection densities was shown based on the reflection density of white paper, and the worst fogging among the four colors was shown based on the following evaluation criteria.

(Evaluation criteria)
A: Less than 0.6% B: 0.6 to less than 1.1% C: 1.1 to less than 1.6% D: 1.6 to less than 2.1%

<Image density stability>
The image density is measured with a color reflection densitometer (for example, X-RITE 404 Amanufactured by X-Rite Co.). The difference between the initial density of the solid image of each color and the density after the completion of the printing of 50,000 sheets was measured, and the largest density difference among the four colors was shown based on the following evaluation criteria.
○: 0.1 or less Δ: 0.2 to 0.3 or less ×: 0.3 or more

[Image uniformity / image quality]
After 50,000 images were printed out, a single-color solid image, a four-color halftone image superimposed image, and an original photographic image were printed out, and the image uniformity and image quality were visually evaluated.
A: Very good (uniform images cannot be confirmed and image quality is good)
○: Good (Slight image unevenness can be confirmed, but there is no practical problem at all)
Δ: Practical use possible (image unevenness can be confirmed and image quality is slightly worse, but there is no problem in practical use)
×: Not practical (image unevenness is significant and image quality is practically difficult)

[Image defects due to adhesion of inorganic fine particles to the photoreceptor]
As a means for evaluating the adhesion of inorganic fine particles to the photoconductor, after the completion of 50,000-sheet printing, a halftone image is printed out, and the surface of the photoconductor is inspected with an inorganic fine particle and the inorganic fine particles on the photoconductor The presence or absence of image defects accompanying the adhesion of the film was confirmed and evaluated according to the following criteria.
A: There is little adhesion of inorganic fine particles to the surface of the photoreceptor, and the image is good.
○: Adherence of inorganic fine particles is observed on the surface of the photoconductor, but the image is not missing and good.
Δ: A large amount of inorganic fine particles are observed on the surface of the photoreceptor, and some image loss is observed.
X: A large amount of inorganic fine particles and toner are observed on the surface of the photoreceptor, and image loss is observed.

<Examples 2 to 5>
In Example 1, resin and wax as shown in Tables 3 and 5 were used, and the procedure was substantially the same except that the manufacturing process was adjusted and changed so that the transmittance and circularity shown in the table were obtained. Using the cyan toners 2, 3, 5, and 6 obtained, the same evaluation as in Example 1 was performed. The results are shown in Table 7. As shown in Table 7, in the cyan toner 3, all evaluation items in the HH environment were slightly bad. This is presumably due to the fact that the toner transmittance is slightly low, so that it is easily affected by humidity, the charge is lowered, and the charge distribution is expanded.

<Example 6>
After adding 450 parts by mass of 0.1 mol / liter-Na ₃ PO ₄ aqueous solution to 710 parts by mass of ion-exchanged water and heating to 60 ° C., using a clear mixer (M Technique Co., Ltd.) 3,500 revolutions / Stir in minutes. To this, 68 parts by mass of a 1.0 mol / liter-CaCl 2 aqueous solution was added to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

On the other hand, the dispersoid system is
-Styrene monomer 170 mass parts-n-butyl acrylate 30 mass parts-C.I. I Pigment Blue 15: 3 15 parts by mass / saturated polyester 10 parts by mass (polycondensate Tg = 65 ° C., Mw = 10000 of propylene oxide-modified bisphenol A and isophthalic acid)
-Aluminum ditertiary butylsalicylate compound 3 parts by mass-The following compound (1) 25 parts by mass (DSC peak temperature 59.4 ° C, Vickers hardness 1.5)

上記処方のうち、カーボンブラック、サリチル酸金属化合物とスチレン単量体１００質量部をアトライター（三井三池化工機製）を用い３時間分散し、着色剤分散液を得た。次に、着色剤分散液に上記処方の残りすべてを添加し、６０℃に加温し３０分間溶解混合した。これに、重合開始剤である２，２’−アゾビス（２，４−ジメチルバレロニトリル）１０質量部を溶解し、重合性単量体組成物を調製した。

Among the above-mentioned formulations, carbon black, salicylic acid metal compound and 100 parts by mass of a styrene monomer were dispersed for 3 hours using an attritor (manufactured by Mitsui Miike Chemical Industries) to obtain a colorant dispersion. Next, the rest of the above formulation was added to the colorant dispersion, heated to 60 ° C., and dissolved and mixed for 30 minutes. In this, 10 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was dissolved to prepare a polymerizable monomer composition.

The polymerizable monomer composition was put into the aqueous dispersion medium and granulated for 15 minutes while maintaining the rotation speed. Then, the stirrer was changed from the high-speed stirrer to the propeller stirring blade, the internal temperature was raised to 80 ° C., and the polymerization was continued for 10 hours at 50 rpm. After completion of the polymerization, the slurry was cooled, diluted hydrochloric acid was added, and Ca ₃ (PO ₄ ) ₂ was dissolved, followed by filtration and washing with water to obtain wet colorant-containing polymer particles having a water content of 22% by mass. The polymer particles obtained had a polymerization average particle size of 6.2 μm.

  The obtained wet colorant-containing polymer particles were crushed and then dried using a continuous instantaneous airflow dryer (flash dryer FJD-4: manufactured by Seishin Enterprise Co., Ltd.). As drying conditions, 90 ° C. air was blown at a linear velocity of 16.5 m / sec, and wet colorant-containing polymer particles were continuously supplied at 20 kg / hr. The time required for drying was 0.7 seconds. It was 0.1 mass% when the moisture content was measured. At this time, the amount of the polymerizable monomer remaining in the toner particles was 530 ppm. There was no occurrence of lumps due to toner aggregation, and the passing rate of a sieve having an aperture of 149 μm was 97%.

  Next, about 30 kg of the primary dried toner particles taken out were dried using a 100 liter Nauter type vacuum dryer (NXV-1 type: manufactured by Hosokawa Micron Corporation). As drying conditions, the jacket heating temperature was 50 ° C., the degree of vacuum was 2 to 5 kPa, and nitrogen gas was supplied from the bottom at 5.0 N liters / min to perform drying for 3 hours.

  The coarse powder in the obtained toner particles was removed by classification, and external addition was performed in the same manner as in Example 1 to obtain cyan toner 9. The same evaluation as in Example 1 was performed using the cyan toner 9 obtained. The results are shown in Table 7.

  Although not shown in Table 7, the same evaluation was performed with a commercially available copying machine iRC3100 (manufactured by Canon: image transfer device having an intermediate transfer member and a cleaning mechanism). A defect has occurred.

<Example 7>
A cyan toner 10 was obtained in the same manner as in Example 6 except that the manufacturing conditions were changed so that the circularity shown in Table 5 was obtained. Using the cyan toner 10 obtained, the same evaluation as in Example 1 was performed. The results are shown in Table 7. Although not shown in Table 7, the same evaluation was performed with a commercially available copying machine iRC3100 (manufactured by Canon: image transfer apparatus having an intermediate transfer member and a cleaning mechanism). A defect has occurred.

<Comparative Example 1>
In Example 1, the spheroidizing treatment was performed not by the apparatus A but by a classifier (elbow jet classifier) that does not perform spheronization, and then substantially the same except that a surfing system manufactured by Nippon Pneumatic Co., Ltd. was used. And cyan toner 4 was obtained. Using the cyan toner 4 obtained, the same evaluation as in Example 1 was performed. As a result, the amount of the release agent in the vicinity of the toner surface was small in the initial stage of durability, and offset occurred during fixing.

<Comparative Examples 2 and 3>
In Example 1, as shown in Tables 3 and 5, after making a resin and wax and performing a spheroidizing process not an apparatus A but a classifying apparatus (elbow jet classifier) that does not spheroidize, Nara Machinery Co., Ltd. The cyan toners 7 and 8 were obtained in substantially the same manner except that the above hybridization system was used. Using the cyan toners 7 and 8 obtained, the same evaluation as in Example 1 was performed. The results are shown in Table 7. As Table 7 shows, it deteriorated in all evaluations. This is considered to be caused by the fact that the carrier and the developing sleeve (developer carrier) are contaminated by the releasing agent and the like and the charging stability is deteriorated because the amount of the releasing agent near the toner surface is large.

<Examples 8 to 20>
As shown in Table 5, a cyan toner was obtained in the same manner as in Example 1 except that silica particles b to m were used instead of silica particles a. Using the cyan toners 11 to 23 obtained, the same evaluation as in Example 1 was performed. The results are shown in Table 7. Although the cyan toner 19 was slightly fogged or adhered to the photoreceptor, it was slightly deteriorated. This is presumably because silica particles were surface treated with metal alkoxide without using water vapor, so that silica particles and the like were slightly more agglomerated than those using water vapor, and the fluidity of the toner particles was slightly deteriorated. Further, it is presumed that the surface treatment of the silica particles is slightly uneven or because the adhesion of the metal alkoxide to the silica surface is slightly weak, so that it is easy to adhere to the photoreceptor.

<Comparative example 4>
As shown in Table 5, cyan toner 24 was obtained in the same manner as in Example 1 except that silica particle n was used instead of silica particle a. Using the cyan toner 24 thus obtained, the same evaluation as in Example 1 was performed. The results are shown in Table 7. As Table 7 shows, image defects due to adhesion of silica particles to the photoreceptor deteriorated. This is because the silica particles are not surface-treated with metal alkoxide, so the adhesion to the photoconductor is strong, and it fuses to the photoconductor through long-term use, and further the toner fuses, and the image uniformity / It is thought that the image quality has deteriorated.

<Examples 21 to 30>
As shown in Table 6, cyan toners 25 to 34 were obtained in the same manner as in Example 1 except that the toner particles were wax, silica particles a, m, or n and inorganic fine particles 1 to 8 were added and externally added. . The same evaluation as in Example 1 was performed using the obtained cyan toners 25 to 34. The results are shown in Table 7.

<Comparative Example 5>
As shown in Table 6, cyan toner 35 was obtained in the same manner as in Example 31 except that silica particle 1 was used instead of silica particle a. Using the cyan toner 35 obtained, the same evaluation as in Example 1 was performed. The results are shown in Table 7.

  As Table 7 shows, image defects due to adhesion of silica particles and inorganic fine particles to the photoreceptor were deteriorated. This is because silica particles and inorganic fine particles are not surface-treated with metal alkoxide, so that the adhesion to the photoconductor is strong, and it fuses to the photoconductor through long-term use, and further, the toner is fused. It seems that uniformity and image quality deteriorated.

<Examples 31 and 32>
Cyan toners 36 and 37 were obtained in the same manner as in Example 6 except that the amount of Ca ₃ (PO ₄ ) ₂ was adjusted and cyan toner particles were produced so as to have particle diameters as shown in Table 6. The same evaluation as in Example 1 was performed using the obtained cyan toners 36 and 37. The results are shown in Table 7. With cyan toner 37, the transfer efficiency and fog were slightly deteriorated, so other evaluation items were also slightly deteriorated. This is presumably because the toner particle size is small, the charge amount per unit weight is large, and the fluidity is poor.

<Examples 33 and 34>
In Example 1, cyan toners 38 and 39 were obtained in substantially the same manner except that the manufacturing process was adjusted and changed so that the toner particle diameter was as shown in Table 6. The same evaluation as in Example 1 was performed using the cyan toners 38 and 39 obtained. The results are shown in Table 7. As shown in Table 7, since the cyan toner 39 has a large particle size, the image quality and all other items were slightly inferior.

In the toner production method of the present invention, the finely pulverized product is classified and surface-modified, and the surface is preferably used in a process for obtaining surface-modified toner particles having a suitable particle size distribution. Schematic cross section of an example of reformer (A) Schematic horizontal projection of the classification rotor, and (B) Schematic sectional view of the classification rotor. (A) Horizontal projection view of distributed rotor and (B) Schematic vertical projection view of distributed rotor (A) The figure for demonstrating the diameter of a guide ring, (B) The perspective view of the support body of a guide ring and a guide ring (A) A schematic horizontal projection of a square disk, and (B) a schematic vertical projection of a square disk. (A) Schematic horizontal projection of liner, (B) Partial explanatory diagram of liner FIG. 7 is a partial flowchart for explaining the toner production method of the present invention. (A) A figure for explaining the clearance between the guide link and the square disk, and (B) a figure for explaining the clearance between the square disk and the liner.

Explanation of symbols

30 Main body casing 31 Cooling jacket 32 Dispersion rotor 33 Square disk 34 Liner 35 Classification rotor 36 Guide ring 37 Raw material inlet 38 Raw material supply valve 39 Raw material supply port 40 Product discharge port 41 Product discharge valve 42 Product extraction port 43 Top plate 44 Fine powder Discharge unit 45 Fine powder discharge port 46 Cold air introduction port 47 First space 48 Second space 49 Surface modification zone 50 Classification zone 315 Constant supply device 319 Cold air generation means 320 Cold water generation means 321 Toner particle transport means 359 Cyclone inlet 362 Bug 364 Blower 369 Cyclone 380 Raw material hopper

Claims (11)

In at least toner particles having a binder resin, a colorant and a release agent, and at least toner having silica particles,
The transmittance of the toner in 45% MeOH is 10 to 70%,
The toner, wherein the silica particles are silica particles (A) which are surface-treated by hydrolyzing at least a metal alkoxide represented by the following general formula (1).
M (OR) n (1)
(However, M represents a metal element, R represents an alkyl group, and n represents an integer. When n is 2 or more, R may be the same alkyl group or a plurality of alkyl groups having different carbon numbers and structures. Good.)   2. The toner according to claim 1, wherein the silica particles surface-treated by hydrolyzing the metal alkoxide have an Mw value (methanol hydrophobicity) of 50% to 80%.   The toner according to claim 1, wherein the silica particles have an element molar ratio of M / Si (M is a metal element derived from a metal alkoxide) of 0.001 to 0.5.   4. The toner according to claim 1, wherein the silica particles are obtained by attaching metal alkoxide and then hydrolyzing the metal alkoxide attached to the surface by contacting with water vapor. 5. At least toner particles having a binder resin, a colorant and a release agent, and a toner having at least two kinds of inorganic fine particles (B) and inorganic fine particles (C),
At least one of the inorganic fine particles (B) and the inorganic fine particles (C) is a silica particle that is surface-treated by hydrolyzing a metal alkoxide represented by the following general formula (1): .
M (OR) n (1)
(However, M represents a metal element, R represents an alkyl group, and n represents an integer. When n is 2 or more, R may be the same alkyl group or a plurality of alkyl groups having different carbon numbers and structures. Good.)   The toner according to claim 5, wherein the inorganic fine particles (C) are spherical silica particles, and the average particle size of the inorganic fine particles (C) is larger than that of the inorganic fine particles (B).   7. The inorganic fine particles (B) and the inorganic fine particles (C) are both surface-treated by hydrolyzing the metal alkoxide represented by the general formula (1). Toner.   The toner according to claim 5, wherein the inorganic fine particles (C) have an average particle diameter of 0.06 to 0.30 μm.   The toner according to claim 1, wherein the toner has hydrophobic titanium oxide. The toner has a weight average particle diameter of 3.0 to 11.0 μm, and contains 3 to 50 number% of toner particles having a particle diameter of 4 μm or less in the number particle size distribution;
The toner according to claim 1, wherein an average circularity of the toner is in a range of 0.915 to 0.990.   The binder resin is (a) a polyester resin, (b) a hybrid resin having a polyester unit and a vinyl polymer unit, or (c) a mixture of a hybrid resin and a vinyl polymer, or (d 11. The resin according to any one of claims 1 to 10, comprising a resin selected from either a mixture of a hybrid resin and a polyester resin, (e) or a mixture of a polyester resin and a vinyl polymer. Toner.

Images