JP2005338809A - Image forming method and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming method in which high gradation and excellent halftone reproducibility are ensured, carrier adhesion is prevented and occurrence of microcracks in a photoreceptor surface is suppressed, and by which stable images can be obtained over a prolonged period of time. <P>SOLUTION: In the image forming method in which an electrostatic latent image is formed on a photoreceptor having at least a charge generating layer and a charge transport layer on a conductive support and the electrostatic latent image is developed with a two-component developer including a toner and carrier, the photoreceptor has a modulus of elastic deformation of a surface in the range of 46-65% and a universal hardness of 1.5×10<SP>8</SP>-2.3×10<SP>8</SP>N/m<SP>2</SP>, the charge transport layer has a thickness of 8.0-20.0 μm, the toner has a weight-average particle diameter of 3.0-10.0 μm, and the carrier has a volume-average particle diameter of 15.0-60.0 μm and an average circularity C of 0.830-0.950, and contains ≤20% by number of particles having a value of (average circularity C-2σ) or below. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming method for forming an image by developing an electrostatic latent image on a photoreceptor using a two-component developer having a toner and a carrier used in electrophotography, electrostatic recording method, etc. The present invention relates to an image forming apparatus.

  Generally, in an image forming apparatus that records an image on a recording medium such as paper, such as a copying machine or a printer, an electrophotographic system is employed as a system for recording the image on the recording medium.

  In the electrophotographic system, a photosensitive drum having a surface coated with a photosensitive material is used as an electrostatic latent image carrier. First, after the surface of the photosensitive drum is uniformly charged, the surface of the photosensitive drum is irradiated with laser light, and a potential difference is given between the irradiated portion and the non-irradiated portion.

  Next, a toner image is formed on the surface of the photosensitive drum by attaching the charged toner to the surface of the photosensitive drum in accordance with the potential using a developer having toner and carrier. Thereafter, the toner image is transferred to a recording medium, and the toner is fixed on the recording medium by heat, pressure, or the like to form an image.

  Recently, demands such as lower running costs of toners and photosensitive drums with higher image quality and higher speed of output devices have become stronger, and the photosensitive drums used in the above-mentioned electrophotographic systems are more necessary due to the necessity of high resolution. A thin photosensitive layer is used, and on top of that, it is necessary to extend the life of the photosensitive drum in order to reduce the running cost. Therefore, the electrical, mechanical strength and wear resistance of the photosensitive member surface are improved. Is planned.

  In order to achieve high resolution and high durability of the photoreceptor, proposals have been made to use a curable resin for the surface layer. When a curable resin is used for the surface layer, the mechanical strength is increased and it is difficult to scrape and scratches are less likely to occur than a thermoplastic resin, resulting in a longer life. Furthermore, in Japanese Patent Application Laid-Open No. 2003-345049, a surface layer using various energy (heat, ultraviolet rays, electron beams, etc.) is formed on the surface of the photoreceptor in order to achieve high durability including high resolution of the photoreceptor. A method has been proposed (see Example 1). This shows excellent potential characteristics and image characteristics even in the initial stage and after the endurance even for a thin film having a total thickness of 15 μm including the photosensitive layer and the surface layer.

  Such a thin-film photoreceptor forms a sharper and higher charge density latent image when the same image is formed as compared with a thick-film photoreceptor (see, for example, Patent Documents 1 and 2). . When such a latent image is developed, a sharper image is obtained, which is preferable. However, in the characteristics of the photoreceptor potential and the image density, the charge density is inversely proportional to the film thickness of the photoreceptor. Therefore, in order to fill this charge with toner, the toner amount increases in inverse proportion to the film thickness. That is, the slope of the γ curve becomes steep (for example, if the photosensitive member film thickness is halved, the charge density necessary to obtain a certain potential is doubled. To satisfy this charge with toner, the amount of toner is used. Is doubled, that is, the fluctuation of the image density with respect to the fluctuation of the contrast potential is abrupt). When such a photoconductor is used, a very sharp image can be obtained with a black-and-white copying machine or printer. However, with a full-color copying machine or printer that requires a halftone image quality, the slope of the γ curve in the halftone area. In some cases, it is difficult to reproduce halftones due to the steepness of the image, or color reproducibility becomes difficult due to a large change in density due to slight potential fluctuations. Further, in a thin film photoreceptor, the contrast potential tends to be small, and the above tendency tends to become more prominent.

On the other hand, an approach from a developer has been made for the purpose of improving image quality (see, for example, Patent Document 3). In order to improve the image quality, the toner has a small particle size to define the particle size distribution, the carrier has a smaller particle size, and the shape is specified to provide excellent fluidity, resolution, gradation, and fine line reproducibility. Proposals for excellence have been made. The reduction in the particle size of the toner and carrier is very effective for improving the image quality. However, when the thin film photoconductor having a high resolution but a steep γ curve as described above is used, In order to improve the gradation, it is necessary to greatly increase the toner charge amount, and it may not be sufficient to satisfy the developability in that case, that is, the so-called toner separation from the carrier. Also, when the toner charge amount is high, the counter charge is likely to accumulate on the carrier, and the carrier is likely to adhere. In this case, if the carrier shape is indefinite, even if the photosensitive drum has a strong protective layer, fine scratches are formed on the surface. In some cases, the surface of the photosensitive drum is matted as the durability progresses, and the halftone part may be rough or streaked.
JP 05-216249 A Japanese Patent Laid-Open No. 07-72640 Japanese Patent Laid-Open No. 06-332237

  An object of the present invention is to provide an image forming method and an image forming apparatus that solve the above-mentioned problems.

  That is, an object of the present invention is to obtain a high-quality image with high gradation (high contrast) in a system using a high-resolution thin film photoconductor, and further prevent carrier adhesion and output a stable image over a long period of time. An object is to provide an image forming method and an image forming apparatus.

  It is another object of the present invention to provide an image forming method and an image forming apparatus capable of outputting a high-quality image having a high image density, in which halftone shakiness is suppressed even in the initial stage and after the endurance.

  That is, the present invention increases the amount of toner carried on the carrier by adjusting the hardness and elastic deformation rate of the photoreceptor surface and the layer thickness of the charge transport layer, and controlling the shape of the toner and the shape distribution of the carrier. Therefore, it is possible to achieve high gradation and halftone reproduction, prevent carrier adhesion, and obtain a stable image over a long period of time without generating fine scratches on the surface of the photoreceptor.

The first invention of the present invention uses a two-component developer that forms an electrostatic latent image on a photoreceptor having at least a charge generation layer and a charge transport layer on a conductive support and contains a toner and a carrier. In the image forming method for developing the electrostatic latent image,
The photoreceptor has a surface elastic deformation ratio of 46 to 65%, a universal hardness value (HU) of 1.5 × 10 ^{8 to} 2.3 × 10 ⁸ (N / m ² ), and the charge transport layer. Has a layer thickness of 8.0 to 20.0 μm,
The toner has a weight average particle diameter (D4) of 3.0 to 10.0 μm,
The carrier has a volume average particle diameter (Dv) of 15.0 to 60.0 μm, an average circularity C of 0.830 to 0.950, and a particle having a circularity of (average circularity C-2σ) or less. (Σ is a standard deviation of carrier circularity) is 20% by number or less.

  The second invention of the present invention contains at least one or more silicone-based resins and fluorine-based resins in order to improve toner separation even when high chargeability is imparted to the toner and to suppress carrier adhesion. A carrier whose surface is coated with a resin is used.

A third invention of the present invention is a magnetic material-dispersed resin carrier having a magnetic material and a binder resin in order to increase the toner carrying amount, improve the halftone reproducibility, and obtain a high-quality image, The true specific gravity of the carrier is 3.0 to 4.0 g / cm ³ , and the magnetization intensity per carrier volume at 79.6 kA / m is 80 to 250 kAm ² / m ³ (emu / g · g / cm ³ = emu / cm ³ ) is used.

  The fourth aspect of the present invention uses a toner having a weight average particle diameter of 4.0 to 8.0 μm and an average circularity of 0.920 to 1.000 in order to obtain a higher quality image. It is characterized by that.

  The fifth aspect of the present invention is characterized in that a charge transport layer having a layer thickness of 8.0 to 16.0 μm is used in order to obtain a higher quality image.

  The sixth invention of the present invention has an appropriate surface hardness and elasticity, prevents scraping (wear) and generation of fine scratches (mat formation), and forms a stable image over a long period of time. The charge transport layer is divided into a first charge transport layer and a second charge transport layer, and the first charge transport layer is a layer in which a charge transport material is dispersed in a binder resin, and the second electrification layer The transport layer is a layer that forms a surface layer, and has a charge transport layer that is a curable resin obtained by polymerizing and curing a compound having a polymerizable functional group represented by the following structural formula (1). It is characterized by using a body.

(E is a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, a cyano group, a nitro group, an alkoxy group, —COOR ₁ (R ₁ is a hydrogen atom, A halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent and an aryl group which may have a substituent, -CONR ₂ R ₃ (where R ₂ and R ₃ are hydrogen) An atom, a halogen atom, an alkyl group that may have a substituent, an aralkyl group that may have a substituent, and an aryl group that may have a substituent, which may be the same or different W is a divalent arylene group which may have a substituent or a divalent alkylene group which may have a substituent, -COO-, -C-, -O-, -OO- _{, -S -, - CONR 4 -} (R 4 is a hydrogen atom, c A rogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent or an aryl group which may have a substituent, and f represents 0 or 1.)

  According to the present invention, by adjusting the elastic modulus of the surface of the thin film photoreceptor to a specific range and controlling the shape of the carrier, high gradation and halftone reproducibility are improved, carrier adhesion is prevented, and the photoreceptor It is possible to obtain an image forming method and an image forming apparatus capable of preventing fine scratches on the surface and obtaining a stable image over a long period of time.

  As a result of intensive studies on an image forming method using a thin film photoreceptor, the present inventors have determined that when a thin film photoreceptor is used and a two-component developer is developed, the shape of the carrier affects the degree of carrier adhesion. It has been found that the shape of the carrier adhering to the carrier is irregular and has a finer scratch on the surface of the photoconductor, resulting in a matte surface of the photoconductor. Therefore, the thin film photosensitive member has a surface protective layer, and the surface protective layer has a specific elastic modulus, thereby making it possible to achieve both the elastic force to prevent the surface of the photosensitive member from being scraped and to relieve the stress against rubbing. We have found that by achieving a surface that is difficult to stick and controlling the distribution of the carrier shape as an approach from the carrier, it is possible to reduce the amount of carrier adhesion and at the same time avoid scratches. Furthermore, when developing on a high-capacity photoconductor such as a thin-film photoconductor, if the toner charge amount is low, the toner will be developed more than necessary, and if an appropriate amount of toner is developed, the contrast potential cannot be obtained. The gradation cannot be obtained. When the toner charge amount is increased, the toner is separated from the carrier, that is, developability is lowered, so that a desired image density may not be obtained. Thus, it has been found that by controlling the toner particle size and the shape of the carrier, it is possible to achieve good toner separation even when the toner charge amount is increased, and that a high-quality image with high gradation can be obtained.

  Details will be described below.

  An example of the image forming method of the present invention will be described with reference to FIG. The present invention is not limited to the image forming method and the image forming apparatus.

  The image forming apparatus shown in FIG. 1 forms a color image using two or more toners having different colors. At least (I) a charging process for charging the surface of the photoreceptor, and (II) the charging process. A latent image process for sequentially forming an electrostatic latent image corresponding to each color on the formed photosensitive member, and (III) the electrostatic latent image formed on the photosensitive member is visualized with a corresponding color toner. A developing process for forming a toner image, (IV) a transferring process for transferring the toner images of the respective colors visualized in the developing process to a transfer material, and (V) a toner formed on the transfer material in the transferring process. The image is formed through a step of fixing by heat and pressure.

In such an image forming method, the developing step uses a developing container (10a to 10d) having a plurality of developing units each having a developing roller carrying a two-component developer corresponding to the toner of each color. The developer carried on the developing roller is transferred to the photoconductor (7a-7d) by an electric field (preferably used by superimposing an AC electric field on a DC electric field) to develop the electrostatic latent image formed on the photoconductor Then, a toner image of each color is sequentially formed on the photoreceptor. The amount of developer carried on the developing roller is preferably 0.2 to 0.6 kg / m ² , and the distance between the developing roller and the photosensitive member is 200 to 500 μm, so that the developer magnetic brush and the photosensitive It is preferable for forming a good contact state with the body. In addition, the contrast potential is 200 to 450 V, the development bias is in addition to the DC component, VP-P (voltage between peaks) is 400 to 2500 V, and the frequency is 1.0 to 3.0 kHz (in some cases, the duty is changed). In order to achieve high image quality and high gradation, it is preferable to apply an alternating current component.

  Reference numeral 7a denotes a drum-shaped photoconductor as a first image carrier, which is rotationally driven at a predetermined peripheral speed (process speed) in the direction of the arrow in the figure. The photosensitive member 7a is first uniformly charged to a predetermined potential (charging step) by the charging device 8a, and then exposed by the image exposure device 9a (latent image forming step). In this manner, an electrostatic latent image corresponding to the first color component image (for example, a yellow toner image) of the target color image is formed.

  Next, the electrostatic latent image is developed for the first color (for example, a yellow toner image) by a first developing unit (for example, yellow toner developing unit 10a). Sequentially, the same development is performed by the second to fourth developing units (that is, the magenta toner developing unit 10b, the cyan toner developing unit 10c, and the black toner developing unit 10d) (developing step).

  The toner image formed on the photoconductor in the development process is subjected to a transfer process. As shown in FIG. 1, the transfer process used in the image forming method of the present invention is formed on a transfer material by sequentially superimposing and transferring toner images of respective colors formed on a photoreceptor on an intermediate transfer body. A primary transfer process for forming a color toner image to be formed on the intermediate transfer member and a secondary transfer process for transferring the color toner image formed on the intermediate transfer member onto a transfer material may be used.

  In FIG. 1, an intermediate transfer belt 14 as an intermediate transfer member is driven to rotate in the direction of the arrow at the same peripheral speed as the photosensitive member 7a (up to 7d). In the process in which the toner image of the first color (for example, yellow) formed on the photoconductor 7a passes through the contact portion between the photoconductor 7a and the intermediate transfer belt 14, it passes through the primary transfer roller 13a (˜13d). Then, the image is sequentially transferred onto the outer peripheral surface of the intermediate transfer belt 14 by an electric field formed by a bias applied to the intermediate transfer belt 14. The surface of the photoreceptor 7a after the transfer of the first color toner image to the intermediate transfer belt 14 is cleaned by the cleaning device 11a. Color toner images are similarly formed on the intermediate transfer belt 14 at other color (magenta, cyan, and black) stations.

  Next, the color toner image on the intermediate transfer belt 14 is transferred to a transfer material. Reference numeral 4 denotes a secondary transfer roller, which is opposed to the secondary transfer counter roller 3 and is supported in parallel so as to be separated from the lower surface portion of the intermediate transfer belt 14.

  As the primary transfer bias for transferring the toner image from the photoreceptor to the intermediate transfer belt, a bias having a polarity opposite to that of the toner is applied. The applied voltage is, for example, in the range of +100 V to +2 kV.

  The transfer material P carried on the paper feed tray 6 passes through the paper feed roller 16 and is fed to a contact portion between the intermediate transfer belt 14 and the secondary transfer roller 4 at a predetermined timing. At this time, the secondary transfer bias is applied to the secondary transfer roller 4, whereby the color toner image transferred onto the intermediate transfer belt 14 is secondarily transferred to the transfer material P. The transfer material P onto which the color toner image has been transferred is introduced into the fixing device 15 and fixed by heating.

  After the image transfer to the transfer material P is completed, the toner remaining on the intermediate transfer belt (transfer residual toner) is scraped off by the belt cleaning device 5 and carried to a waste toner box.

  The carrier of the present invention needs to have a volume average particle diameter (Dv) of 15.0 to 60.0 μm. Particles having a volume average particle diameter of less than 15.0 μm tend to be irregular in shape, and even if the shape is substantially spherical, the carrier tends to adhere, and the photoconductor may be slightly scratched. If it exceeds 60.0 μm, sufficient charge cannot be imparted to the toner, and the developing magnetic brush tends to be stiff, which may cause unevenness in scratches or prevent good images from being obtained. is there. More preferably, a volume average particle diameter of 20.0 to 40.0 μm is excellent in high image quality and durability stability.

  The carrier of the present invention has a number-based average circularity C of 0.830 to 0.950, preferably 0.870 to 0.940. The degree of circularity is a coefficient representing the shape of the roundness of the particle, is determined from the maximum diameter of the particle and the measured particle projected area, becomes a perfect sphere (perfect circle) as it becomes 1.000, and becomes elongated as the value decreases. It tends to be indefinite. The carrier according to the present invention has a shape deviated from a sphere to some extent, and the distribution of the circularity is narrowly controlled so that the number of particles having a circularity of (average circularity C-2σ) or less is 20% by number or less. Is. Such a carrier is excellent in charge imparting property to the toner, hardly adheres to the carrier, and even when the carrier adheres, the occurrence of scratches on the surface of the photoreceptor is suppressed. More preferably, the number of particles having a circularity of (average circularity C-2σ) or less is 15% by number or less, which is more suitable for imparting high charge to the toner and improving toner separation.

The carrier of the present invention has a magnetization intensity per volume measured in a magnetic field of 79.6 (kA / m) of 80 to 250 kAm ² / m ³ (emu / g · g / cm ³ = emu / cm ³ ). And more preferably 100 to 210 kAm ² / m ³ . When the intensity of magnetization per volume is less than 80 kAm ² / m ³ , the magnetic binding force to the sleeve becomes insufficient, and even a substantially spherical shape is likely to adhere to the carrier and damage the photoreceptor. There is. When it exceeds 250 kAm ² / m ³ , the developer magnetic brush becomes stiff and it is likely that unevenness in the stitches is likely to occur. The intensity of magnetization per volume is obtained by multiplying the true specific gravity of the carrier by the intensity of magnetization of the carrier (Am ² / kg).

The carrier of the present invention preferably has a true specific gravity of 3.0 to 4.0 g / cm ³ , more preferably 3.2 to 3.8 g / cm ³ . When the true specific gravity is in this range, the load on the toner is small in the stirring and mixing of the carrier and the toner, the toner spent on the carrier is suppressed, and the toner separation can be maintained well for a long period of time. This is preferable because adhesion of the carrier is suppressed. In order to obtain a preferable true specific gravity, the carrier is preferably a magnetic substance-dispersed resin carrier having a magnetic substance and a binder resin.

  The magnetic carrier of the present invention is preferably a magnetic material-dispersed resin carrier using a carrier core in which a magnetic material is dispersed in a binder resin. Among them, it is preferable to use a magnetic powder-dispersed resin carrier using a carrier core directly manufactured through a polymerization step in order to increase the average circularity and narrow the circularity distribution. The number average particle size of the magnetic material used is preferably about 80 to 800 nm in order to prevent the magnetic material from detaching, to increase the carrier strength, and to make the carrier shape approximately spherical, so that variation in shape is suppressed.

  The amount of the magnetic material used in the magnetic material-dispersed resin carrier is 70 to 95% by mass (more preferably 80 to 92% by mass) with respect to the carrier to reduce the true specific gravity of the carrier, and mechanical It is preferable for ensuring sufficient strength. Moreover, it is also preferable for suppressing the abundance of amorphous carriers with low circularity. Furthermore, in order to change the magnetic properties of the carrier, the magnetic material dispersed core particles may contain a nonmagnetic inorganic compound in addition to the magnetic material. The number average particle diameter of the nonmagnetic inorganic compound is preferably about 100 to 1000 nm because the specific resistance of the carrier can be easily controlled.

  When a nonmagnetic inorganic compound is used in combination with a magnetic substance, the magnetic substance is contained in an amount of 50% by mass or more based on the total amount of the magnetic substance and the nonmagnetic inorganic compound. This is preferable for preventing carrier adhesion.

In the magnetic material-dispersed resin carrier, the magnetic material is preferably magnetite fine particles or magnetic ferrite fine particles containing at least an iron element and a magnesium element, and the nonmagnetic inorganic compound is hematite (α-Fe ₂ O ₃ ) fine particles are more preferable for adjusting the magnetic properties and true specific gravity of the carrier.

  Examples of the binder resin that forms the carrier core include vinyl resins having a methylene unit in the polymer chain, polyester resins, epoxy resins, phenol resins, urea resins, polyurethane resins, polyimide resins, cellulose resins, and polyether resins. These resins may be used as a mixture.

  Examples of vinyl monomers for forming the vinyl resin include styrene; o-methylstyrene, m-methylstyrene, p-methylstyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p- n-butyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy Styrene derivatives such as styrene, p-chlorostyrene, 3,4-dichlorostyrene, m-nitrostyrene, o-nitrostyrene, p-nitrostyrene; ethylene and unsaturated monoolefins such as ethylene, propylene, butylene, isobutylene; Unsaturated diolefins such as butadiene and isoprene; vinyl chloride, salts Vinyl halides such as vinylidene, vinyl bromide and vinyl fluoride; vinyl esters such as vinyl acetate, vinyl propionate and vinyl benzoate; methacrylic acid; methyl methacrylate, ethyl methacrylate, propyl methacrylate, methacrylic acid-n -Α-methylene aliphatic monocarboxylic esters such as butyl, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate; acrylic acid; methyl acrylate , Ethyl acrylate, acrylate-n-butyl, isobutyl acrylate, propyl acrylate, acrylate-n-octyl, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-acrylate Acrylic acid esters such as lorethyl and phenyl acrylate; maleic acid and maleic acid half esters; 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 compounds such as N-vinylpyrrole, N-vinylcarbazole, N-vinylindole, N-vinylpyrrolidone; vinylnaphthalene; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, acrylamide; acrolein, etc. . Those obtained by polymerization using one or more of these are used as the vinyl resin.

  The most preferable method for producing a magnetic material-dispersed resin carrier core in the present invention is a method of obtaining a magnetic material-dispersed carrier core particle by mixing a binder resin monomer and a magnetic material and polymerizing the monomer. At this time, as monomers used for the polymerization, in addition to the vinyl monomers described above, bisphenols and epichlorohydrin for forming epoxy resins; phenols and aldehydes for forming phenol resins; urea resins are formed. For this purpose urea and aldehydes, melamine and aldehydes are used. For example, as a method for producing magnetic material-dispersed core particles using a curable phenolic resin, a magnetic material is placed in an aqueous medium, and phenols and aldehydes are polymerized in the presence of a basic catalyst in the aqueous medium. There is a method for obtaining magnetic material-dispersed carrier core particles.

  As phenols for producing a phenol resin, in addition to phenol itself, alkylphenols such as m-cresol, p-tert-butylphenol, o-propylphenol, resorcinol, bisphenol A and a part of benzene nucleus or alkyl group or Examples thereof include compounds having a phenolic hydroxyl group such as halogenated phenols, all of which are substituted with chlorine atoms or bromine atoms. Of these, phenol (hydroxybenzene) is more preferable.

  Examples of aldehydes include formaldehyde and furfural in the form of either formalin or paraaldehyde. Of these, formaldehyde is particularly preferable.

  The molar ratio of aldehydes to phenols is preferably 1.0 to 4.0, particularly preferably 1.2 to 3.0. If the molar ratio of aldehydes to phenols is less than 1.0, particles are difficult to generate, or even if they are generated, the resin is difficult to cure, and the strength of the particles to be generated tends to be weak. . On the other hand, when the molar ratio of aldehydes to phenols is larger than 4.0, unreacted aldehydes remaining in the aqueous medium after the reaction tend to increase.

  Examples of the basic catalyst used in the condensation polymerization of phenols and aldehydes include those used in the production of ordinary resol type resins. Examples of such a basic catalyst include aqueous ammonia, hexamethylenetetramine and alkylamines such as dimethylamine, diethyltriamine, and polyethyleneimine. The molar ratio of these basic catalysts to phenols is preferably 0.02 to 0.30.

In the present invention, the amount of dissolved oxygen at the start of polymerization is controlled as one method for obtaining a substantially spherical carrier having an average circularity of 0.830 or more and 0.950 or less, and for reducing variation in circularity. It is important to. The amount of dissolved oxygen in the reaction medium at the start of the polymerization reaction is preferably 5.0 g / m ³ or less. From an industrial viewpoint, the inert gas introduced into the reaction medium for the purpose of degassing dissolved oxygen during the polymerization reaction is preferably at least one selected from nitrogen gas, argon gas, and helium gas. Further, the introduction amount of the inert gas is 5 vol% / min to 100 vol% / min of the reaction vessel volume before the polymerization reaction, and the gas introduction amount into the reaction medium during the polymerization reaction is 1 vol%. / Min to 20% by volume / min. By reducing the amount introduced during the polymerization reaction compared to before the polymerization reaction, it is possible to prevent the formation of fine particles, and to prevent it from being taken into the normal particles and deformed. . If the flow rate of the introduced gas before the polymerization reaction is less than 5% by volume / min, the substitution efficiency of dissolved oxygen is poor, and if it is more than 100% by volume / min, volatilization of the monomer and the like is promoted, which is not preferable. It is also important to reduce the gas flow rate during the polymerization reaction compared to before the polymerization reaction. When the flow rate of the introduced gas during the polymerization reaction exceeds 20% by volume / min with respect to the reaction vessel volume, the aforementioned fine particles are easily formed. This is considered to be caused by vigorously stirring the reaction medium with gas during the polymerization reaction. On the other hand, when the amount is less than 1% by volume / min, the amount of oxygen present at the interface between the reaction medium and the outside air increases, and fine particles are likely to be generated.

  Furthermore, in order to polymerize the monomer and obtain the magnetic material-dispersed carrier core particles, it is important to control the stirring blade peripheral speed to 1.0 to 3.5 m / sec. When the peripheral speed of the stirring blade is less than 1.0 m / sec, the crushing force of the particles during polymerization tends to be weakened, and irregular particles tend to be formed easily. If it exceeds 3.5 m / sec, fine particles are likely to be formed, and it is likely that irregular shaped particles are likely to be obtained, such as coalescence of the particles and particles of a desired particle diameter.

  As the resin for coating the surface of the carrier, an insulating resin is preferably used. The insulating resin that can be used in this case may be a thermoplastic resin or a thermosetting resin. Specific examples of the resin forming the coating material include thermoplastic resins such as polystyrene, polymethyl methacrylate, acrylic resins such as styrene-acrylic acid copolymer, styrene-butadiene copolymer, and ethylene. -Vinyl acetate copolymer, polyvinyl chloride, polyvinyl acetate, polyvinylidene fluoride resin, fluorocarbon resin, perfluorocarbon resin, solvent-soluble perfluorocarbon resin, polyvinyl alcohol, polyvinyl acetal, polyvinyl pyrrolidone, petroleum resin, cellulose, cellulose acetate, Cellulose derivatives such as cellulose nitrate, methylcellulose, hydroxymethylcellulose, hydroxymethylcellulose, hydroxypropylcellulose, novolac resin, low molecular weight polyethylene, saturated alkyl polyester Resin, polyethylene terephthalate, polybutylene terephthalate, polyarylate such aromatic polyester resins, polyamide resins, polyacetal resins, polycarbonate resins, polyethersulfone resins, polysulfone resins, polyphenylene sulfide resins, polyether ketone resins.

  As the thermosetting resin, specifically, for example, phenol resin, modified phenol resin, malee resin, alkyd resin, epoxy resin, acrylic resin, or a combination of maleic anhydride, terephthalic acid and polyhydric alcohol. Unsaturated polyester obtained by condensation, urea resin, melamine resin, urea-melamine resin, xylene resin, toluene resin, guanamine resin, melamine-guanamine resin, acetoguanamine resin, gliptal resin, furan resin, silicone resin, polyimide, polyamideimide Examples thereof include a resin, a polyetherimide resin, and a polyurethane resin.

  The above-mentioned resins can be used alone or in combination. In addition, a curing agent or the like can be mixed with a thermoplastic resin and cured for use. In a particularly preferred form, it is preferable to use a resin coating material that has a high charge imparting ability with respect to the toner and that has a higher releasability.

  Therefore, the carrier core coating resin preferably contains at least one silicone resin or fluorine resin.

  The silicone resin is preferably used from the viewpoint of adhesion to the core and prevention of spent.

  The silicone resin can be used alone, but is preferably used in combination with a coupling agent in order to increase the strength of the coating layer and to preferably control the charged state of the toner. Furthermore, the above-mentioned coupling agent is preferably used as a so-called primer agent, in which a part of the coupling agent is treated on the surface of the carrier core before being coated with the coating material. By treating the surface of the carrier core with a coupling agent, a coating layer formed thereafter with a coating material can be formed in a more adhesive state with a covalent bond.

  Aminosilane is preferably used as the coupling agent. As a result, an amino group having positive chargeability can be introduced on the surface of the carrier, and high negative charge characteristics can be imparted to the toner.

  Moreover, when coat | covering coat resin on the carrier surface, it is preferable to coat | cover in a reduced pressure state at the temperature of 30-80 degreeC.

The reason is not clear, but is expected to be described below.
(1) A moderate reaction proceeds at the coating stage, and the coating material is uniformly and smoothly coated on the surface of the carrier core.
(2) In the baking step, a low temperature treatment at at least 160 ° C. is possible, and excessive crosslinking of the resin can be prevented, and the durability of the coating layer can be enhanced.

  Specific examples of carrier coat resins that can be used in the present invention include perfluoropolymers such as polyvinyl fluoride, polyvinylidene fluoride, polytrifluoroethylene, and polyfluorochloroethylene, polytetrafluoroethylene, and polytetrafluoroethylene. Perfluoropropylene, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and trifluoroethylene, copolymer of tetrafluoroethylene and hexafluoropropylene, vinyl fluoride and fluorine Fluorine-based resins such as copolymers with vinylidene fluoride and copolymers of vinylidene fluoride and tetrafluoroethylene. In particular, the coating resin most preferably used in the present invention is:

[Wherein, m represents an integer of 1 to 11. ]
A polymer or copolymer of an acrylate ester or a methacrylate ester having a perfluoroalkyl unit represented by the formula:

  The above-mentioned resins can be used alone or in combination. In addition, a curing agent or the like can be mixed with a thermoplastic resin and cured for use.

  In the present invention, when m is 0, it is difficult to exhibit releasability, and when it exceeds 11, the resin is likely to precipitate from the solvent, and it is difficult to obtain a good coating film when coating. . It is more preferable that m is 5 to 9 in order to have both good toner releasability and coat film forming property.

  More preferably, it is excellent in adhesiveness with a core by using resin which has the following general formula (2).

[Wherein, m represents an integer of 1 to 11, and n represents an integer of 1 to 10. ]
Further, a resin having a unit represented by the following general formula (3) and a (meth) acrylic acid ester unit represented by the following general formula (4) is preferable from the viewpoint of separating the toner from the carrier.

[Wherein, m represents an integer of 1 to 11, n represents an integer of 1 to 10, and l represents an integer of 1 or more. ]

[Wherein, R ₁ has hydrogen or a methyl group, R ₂ represents hydrogen, an alkyl group having 1 to 20 carbon atoms, or an aromatic group, and k represents an integer of 1 or more. ]
Furthermore, the copolymer units of the above general formulas (3) and (4) and methyl acrylate, ethyl acrylate, propyl acrylate, (iso) butyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate having a molecular weight of about 2000 to 20,000 ( A resin obtained by graft copolymerization with a macromonomer such as iso) butyl methacrylate is particularly preferred because it can maintain the toner separation characteristics.

  The fluororesin used as the carrier coat resin preferably has a main peak in the molecular weight range of 2,000 to 100,000 in the GPC chromatogram of the THF soluble component, and further has a molecular weight of 2,000 to 100. In addition to the main peak, it preferably has a sub-peak or shoulder in the region of 1,000. Most preferably, the fluororesin forming the coating material has a main peak in the molecular weight range of 20,000 to 100,000 in the GPC chromatogram of the THF soluble component, and a molecular weight of 2,000 to 19,000. It is preferable to have a sub-peak or shoulder in the region. By satisfying the molecular weight distribution, the high charge imparting property to the toner is further improved.

  Further, it is preferable that the coating resin contains fine particles at a ratio of 1 to 40 parts by mass with respect to 100 parts by mass of the coating resin in order to control minute irregularities on the carrier surface and improve toner separation. . As the fine particles, either organic or inorganic fine particles can be used. However, it is necessary to maintain the shape of the particles when coating the carrier, and crosslinked resin particles or inorganic fine particles can be preferably used. Specifically, as the organic fine particles, a crosslinked polymethyl methacrylate resin, a crosslinked polystyrene resin, a melamine resin, a phenol resin, a nylon resin, and as inorganic fine particles, silica, titanium oxide, and alumina may be used alone or in combination. it can. In particular, it is preferable to use a crosslinked polymethyl methacrylate resin or a melamine resin alone or in combination in order to achieve both a high negative charge amount imparted to the toner and a releasability with the toner.

  The particle size of the fine particles has a peak value of 100 to 500 nm (more preferably 150 to 400 nm) on the basis of the number. Depending on the coating amount, fine irregularities on the carrier surface are formed, and toner separation is improved. Is necessary to do.

  Further, adding 1 to 40 parts by mass of the fine particles to 100 parts by mass of the coating resin, and further containing 1 to 15 parts by mass of conductive particles does not reduce the specific resistance of the carrier, and the carrier surface. It is preferable to remove the residual charge of the toner and to improve the toner separation.

The conductive particles preferably have a specific resistance of 1 × 10 ⁸ Ωcm or less, and more preferably have a specific resistance of 1 × 10 ⁶ Ωcm or less. Specifically, the conductive particles are preferably particles selected from carbon black, magnetite, graphite, zinc oxide, and tin oxide. In particular, as a conductive particle, carbon black can be preferably used without impairing irregularities caused by fine particles on the carrier surface with a small particle size. The particle size of the conductive particles has a peak value of 10 to 500 nm (more preferably 20 to 200 nm) on the basis of the number, so that residual charges on the carrier surface can be removed well and desorption from the carrier can be done well. Preferred for preventing.

  The coating amount of the carrier coat resin is 0.3 to 4.0 parts by mass with respect to 100 parts by mass of the carrier core particles. preferable. If the amount is less than 0.3 parts by mass, the charge imparting property may be inferior. If the amount exceeds 4.0 parts by mass, uniform coating becomes difficult, and charge up may occur and carriers may adhere. In order to obtain a good charge amount and toner separation, the amount is more preferably 0.8 to 3.5 parts by mass.

  It is preferable that the carrier and the toner used in the present invention are mixed and used so as to have a specific surface area. The toner concentration is preferably about 5% by mass to 20% by mass in the two-component developer from the viewpoints of charge amount provision, fogging, image density, and the like.

  The toner used in the present invention has a weight average particle diameter (D4) of 3.0 to 10.0 μm. The thickness is preferably 4.0 μm to 8.0 μm, more preferably 4.5 μm to 7.0 μm, from the viewpoint of sufficiently satisfying the dot reproducibility and transfer efficiency. When the weight average particle diameter of the toner is less than 3.0 μm, the specific surface area of the toner becomes large, so that it is difficult to uniformly control the charge amount of each toner and the developability may be lowered. When the weight average particle diameter of the toner exceeds 10.0 μm, the dot reproducibility is inferior, and it is difficult to have a charge amount sufficient to fill the charge of the thin film photoreceptor, which may cause a problem in improving the image quality. . The weight average particle diameter of the toner can be adjusted by pulverization / classification of the toner particles at the time of production and granulation conditions.

  When the contact state between the toner and the carrier or the toner and the photoconductor varies such as point contact or surface contact, the toner separation tends to be non-uniform and the developability tends to decrease. It is in. In order to suppress this, the average circularity of the toner is preferably 0.920 to 1.000. More preferably, it is 0.930 to 1.000.

  The toner of the present invention can be prepared by a conventionally known toner production method such as a kneading / pulverization method, a suspension polymerization method, an emulsion aggregation method, but preferably contains a polyester resin in view of low-temperature fixability. A production method using a kneading / pulverizing method is preferably used. In that case, it is possible to adjust the circularity by using a specific processing device that brings the shape of the toner particles closer to a spherical shape.

  Examples of the device for spheroidizing toner particles include heat treatment devices such as surffusion (manufactured by Nippon Pneumatic Co., Ltd.) for hot-melting the particle surface and spheroidizing device (manufactured by Hosokawa Micron Co., Ltd.). It is done. Alternatively, a hybridizer (manufactured by Nara Machinery Co., Ltd.), a turbo mill (manufactured by Turbo Industry Co., Ltd.), a kryptron (manufactured by Kawasaki Heavy Industries, Ltd.), a mechano-fusion system (manufactured by Hosokawa Micron Co., Ltd.) or the like can be mentioned. .

  When the toner particles are spheroidized, high chargeability is easily obtained. However, when toner particles containing a release agent are spheroidized, the release agent exudes to the surface of the toner particles. It is also preferable to consider. An apparatus capable of performing a spheroidizing process more suitable for balancing the degree of spheroidizing of the toner and the exudation of the release agent will be described in detail with reference to the drawings.

  FIG. 2 is an example of a surface modification apparatus.

  In the surface reforming apparatus shown in FIG. 2, the casing 45, a jacket (not shown) through which cooling water or antifreeze liquid can be passed, and classification means for separating particles having a predetermined particle diameter or more and particles having a predetermined particle diameter or less. A certain classification rotor 31, a dispersion rotor 36 which is a surface treatment means for applying a mechanical shock to the particles to treat the surface of the particles, and a predetermined interval with respect to the outer periphery of the dispersion rotor 36. Of the particles divided by the classification rotor 31, the guide ring 39 that is a guide means for guiding particles having a predetermined particle size or more to the dispersion rotor 36, and the particles divided by the classification rotor 31. Introducing cold air, which is a particle circulating means for sending the particles whose surface has been treated by the dispersion rotor 36 to the classification rotor 31, and a fine powder collecting discharge port 32, which is a discharging means for discharging fine particles having a particle diameter smaller than a predetermined particle size outside the apparatus. 35 comprises a raw material supply port 33 for introducing the treated particles into the casing 45, and a powder discharge port 37 and discharge valve 38 for discharging the treated surface particles from the casing 45 inside. The classification rotor 31 is a cylindrical rotor and is provided on one end face side in the casing 45. The fine powder collection outlet 32 is provided at one end of the casing 45 so as to discharge particles inside the classification rotor 31. The raw material supply port 33 is provided at the center of the peripheral surface of the casing 45. The cold air introduction port 35 is provided on the other end surface side with respect to the end surface provided with the classification rotor on the peripheral surface of the casing 45. The powder discharge port 37 is provided at a position facing the raw material supply port 33 on the peripheral surface of the casing 45. The discharge valve 38 is a valve that freely opens and closes the powder discharge port 37.

  A dispersion rotor 36 and a liner 34 are provided between the cold air introduction port 35, the raw material supply port 33 and the powder discharge port 37. The liner 34 is provided around the inner peripheral surface of the casing 45. As shown in FIG. 3, the dispersion rotor 36 includes a disk and a plurality of rectangular disks 40 arranged along the normal line of the disk at the periphery of the disk. The dispersion rotor 36 is provided on the other end surface side of the casing 45, and is provided at a position where a predetermined interval is formed between the liner 34 and the square disk 40. A guide ring 39 is provided at the center of the casing 45. The guide ring 39 is a cylindrical body and is provided so as to extend from a position covering a part of the outer peripheral surface of the classification rotor 31 to the vicinity of the classification rotor 36. The guide ring 39 includes a first space 41 that is a space between the outer peripheral surface of the guide ring 39 and the inner peripheral surface of the casing 45 in the casing 45, and a second space that is a space inside the guide ring 39. A space 42 is formed.

  The dispersion rotor 36 may have a cylindrical pin instead of the square disk 40. In the present embodiment, the liner 34 is provided with a large number of grooves on the surface facing the square disk 40, but may have no grooves on the surface. Moreover, the installation direction of the classification rotor 31 may be a vertical type as shown in FIG. 2 or a horizontal type. Further, the number of classification rotors 31 may be single or multiple as shown in FIG.

  In the surface reforming apparatus configured as described above, when a certain amount of finely pulverized product is charged from the raw material supply port 33 with the discharge valve 38 closed, the charged finely pulverized product is first blower (not shown). ) And is classified by the classification rotor 31. At that time, the classified fine powder having a particle diameter smaller than the predetermined particle diameter passes through the peripheral surface of the classification rotor 31 and is guided to the inside of the classification rotor 31 and continuously discharged and removed out of the apparatus. Coarse powder having a predetermined particle diameter or more is circulated along the inner periphery (second space 42) of the guide ring 39 by a centrifugal force and is circulated by the dispersion rotor 36, and the gap between the rectangular disk 40 and the liner 34 ( Hereinafter, it is also referred to as “surface modification zone”. The powder guided to the surface modification zone receives a mechanical impact force between the dispersion rotor 36 and the liner 34 and is subjected to a surface modification treatment. The surface-modified particles having undergone surface modification are carried to the classification rotor 31 along the outer periphery (first space 41) of the guide ring 39 on the cold air passing through the inside of the machine. Is discharged out of the machine, and the coarse powder is circulated and returned to the second space 42 and repeatedly subjected to the surface modification action in the surface modification zone. As described above, in the surface modification apparatus of FIG. 2, the classification of the particles by the classification rotor 31 and the treatment of the surface of the particles by the dispersion rotor 36 are repeated. After a certain period of time, the discharge valve 38 is opened and the surface modified particles are recovered from the discharge port 37.

  In such an apparatus, there is almost no exudation of the release agent due to heat, and the toner particles can be easily spheroidized and the exudation of the release agent can be easily adjusted. Is preferred.

  Further, in order to increase the circularity of the toner of the present invention, particles obtained by a direct polymerization method using a vinyl resin as a main component or a polymerization method obtained from an aqueous medium can be used. When the average circularity of the toner is 0.960 or more, the toner can be easily applied to a cleanerless system.

  In the toner of the present invention, a toner used for oilless fixing is preferable, and the release agent is a low molecular weight polyethylene, a low molecular weight polypropylene, a polyolefin copolymer, a polyolefin wax, a microcrystalline wax, a paraffin wax, a Fischer-Tropsch wax, or the like. Fatty hydrocarbon waxes; oxides of aliphatic hydrocarbon waxes such as oxidized polyethylene wax; or block copolymers thereof; fatty acid esters such as carnauba wax, montanate wax, and behenyl behenate as main components Waxes obtained by deoxidizing a part or all of fatty acid esters such as deoxidized carnauba wax. Further, saturated linear fatty acids such as palmitic acid, stearic acid, montanic acid, or long-chain alkyl carboxylic acids having a long-chain alkyl group; unsaturated fatty acids such as brandic acid, eleostearic acid, and valinal acid Saturated alcohols such as stearic alcohol, aralkyl alcohol, behenyl alcohol, carnauvir alcohol, seryl alcohol, melyl alcohol, or long-chain alkyl alcohols having a long-chain alkyl group; polyhydric alcohols such as sorbitol; linol Fatty acid amides such as acid amide, oleic acid amide, lauric acid amide; saturated fatty acids such as methylene bis stearic acid amide, ethylene biscapric acid amide, ethylene bis lauric acid amide, hexamethylene bis stearic acid amide Unsaturated fatty acid amides such as samides, ethylenebisoleic acid amide, hexamethylenebisoleic acid amide, N, N′-dioleyl adipic acid amide, N, N′-dioleyl sebacic acid amide; Aromatic bisamides such as stearamide, N, N'-distearylisophthalamide; fatty acid metal salts such as calcium stearate, calcium laurate, zinc stearate, magnesium stearate (generally referred to as metal soap) Waxes grafted to aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid; partially esterified products of fatty acids and polyhydric alcohols such as behenic acid monoglyceride; by hydrogenation of vegetable oils and fats, etc. The resulting hydroxyl group And methyl ester compounds are exemplified. A hydrocarbon wax is preferable from the viewpoint that the compatibility with the binder resin is appropriate and the release agent can be finely dispersed. The endothermic curve in the differential thermal analysis measurement of the toner has one or more endothermic peaks in the temperature range of 30 to 200 ° C., and the maximum endothermic peak temperature is 65 ° C. to 110 ° C. A toner can be preferably used because it can improve low-temperature fixability and durability.

  The release agent used in the present invention preferably has a content of 1 to 15 parts by mass, more preferably 3 to 10 parts by mass with respect to 100 parts by mass of the binder resin. If the content is less than 1 part by mass, the releasability may not be exhibited well during oilless fixing. When the amount exceeds 15 parts by mass, the release agent tends to ooze out to the toner surface, and developability (toner separation) and transferability may deteriorate.

  As the binder resin that can be used in the toner of the present invention, commercially available resins can be used, but (a) a polyester resin, (b) a hybrid resin having a polyester unit and a vinyl polymer unit, and (c) ) A mixture of hybrid resin and vinyl polymer, (d) a mixture of polyester resin and vinyl polymer, (e) a mixture of hybrid resin and polyester resin, and (f) polyester resin, hybrid resin and vinyl system. It is a resin selected from a mixture with a polymer.

  When a polyester resin is used as the binder resin, a polyhydric alcohol and a polyvalent carboxylic acid, a polyvalent carboxylic acid anhydride, a polyvalent carboxylic acid ester, or the like can be used as a raw material monomer.

  The “polyester unit” in the hybrid resin means a portion derived from polyester. As the polyester monomer constituting the polyester resin and the polyester unit, a polyhydric alcohol and a carboxylic acid component such as a polyvalent carboxylic acid, a polyvalent carboxylic acid anhydride, or a polyvalent carboxylic acid ester having two or more carboxyl groups, and Can be used as a raw material monomer.

  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 -Alkylene oxide adducts of bisphenol A such as bis (4-hydroxyphenyl) propane, 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 A And hydrogenated bisphenol A.

  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.

  Examples of the carboxylic acid component include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid or anhydrides thereof; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid and azelaic acid or anhydrides thereof; And succinic acid substituted with 12 to 12 alkyl groups or anhydrides thereof; unsaturated dicarboxylic acids such as fumaric acid, maleic acid and citraconic acid or anhydrides thereof;

  The polyester resin and the polyester unit have a bisphenol derivative represented by the following general formula as an alcohol component, and a carboxylic acid component composed of a divalent or higher carboxylic acid or an acid anhydride thereof or a lower alkyl ester thereof (for example, fumaric acid). , Maleic anhydride, maleic anhydride, phthalic acid, terephthalic acid, dodecenyl succinic acid, trimellitic acid, pyromellitic acid, etc.), and the polyester resin and polyester unit obtained by polycondensation of these components as a color toner are excellently charged. Since it has characteristics, it is preferable.

[In the formula, R is an ethylene group or a propylene group, x and y are integers of 1 or more, and the average value of x + y is 2 to 10. ]
Examples of the trivalent or higher polyvalent carboxylic acid component for forming a polyester resin having a crosslinking site and a polyester unit include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, Examples include 1,2,4-naphthalene tricarboxylic acid, 2,5,7-naphthalene tricarboxylic acid, 1,2,4,5-benzenetetracarboxylic acid, and acid anhydrides and ester compounds thereof. The use amount of the trivalent or higher polyvalent carboxylic acid component is preferably 0.1 to 1.9 mol% based on the total monomers.

  Examples of the styrene monomer used in the vinyl resin and the vinyl polymer unit include styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, p-methoxy styrene, p-phenyl styrene, p-chloro styrene, 3,4-dichlorostyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, p- Examples include n-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, and the like.

  As acrylic monomers, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, dimethyl acrylate Acrylic esters such as aminoethyl and phenyl acrylate, acrylic acid and acrylic amides, or ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, Methacrylic acid esters such as 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and methacrylic acid As monomers of ethylenically unsaturated monoolefins such as methacrylic acid amides and the like, as monomers of vinyl esters such as ethylene, propylene, butylene and isobutylene, vinyl acetate, vinyl propionate, vinyl benzoate and the like of vinyl ethers As monomers, vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, etc., vinyl ketone monomers, vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone, N-vinyl compound monomers, N-vinyl pyrrole, N- Acrylic acid derivatives or methacrylic acid derivatives such as vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone, vinyl naphthalenes, acrylonitrile, methacrylonitrile, acrylamide, etc. It is. These vinyl monomers may be used alone or in combination of two or more.

  As polymerization initiators used for polymerizing vinyl monomers, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (Cyclohexane-1-carbonitrile), 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azo or diazo polymerization initiators such as azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide , Diisopropyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide, dicyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis (4,4-t-butyl Peroxycyclohexyl) propane Examples thereof include peroxide initiators such as tris- (t-butylperoxy) triazine and polymer initiators having a peroxide in the side chain; persulfates such as potassium persulfate and ammonium persulfate; hydrogen peroxide and the like. .

  Examples of radical polymerizable tri- or higher functional polymerization initiators include tris (t-butylperoxy) triazine, vinyltris (t-butylperoxy) silane, 2,2-bis (4,4-di-t-butylperoxide. Oxycyclohexyl) propane, 2,2-bis (4,4-di-t-amylperoxycyclohexyl) propane, 2,2-bis (4,4-di-t-octylperoxycyclohexyl) propane, 2,2 And radical polymerizable polyfunctional polymerization initiators such as -bis (4,4-di-t-butylperoxycyclohexyl) butane.

  The toner of the present invention can be used in combination with a known charge control agent. Examples of such charge control agents include organometallic complexes, metal salts, and chelate compounds such as monoazo metal complexes, acetylacetone metal complexes, hydroxycarboxylic acid metal complexes, polycarboxylic acid metal complexes, and polyol metal complexes. In addition, carboxylic acid derivatives such as metal salts of carboxylic acids, carboxylic acid anhydrides and esters, and condensates of aromatic compounds are also included. As the charge control agent, phenol derivatives such as bisphenols and calixarenes are also used. In the present invention, it is preferable to use a metal compound of an aromatic carboxylic acid in order to improve the rising of charging.

  In the present invention, the charge control agent preferably has a content of 0.1 to 10 parts by mass, more preferably 0.2 to 5 parts by mass with respect to 100 parts by mass of the binder resin. If the amount is less than 0.1 parts by mass, the change in the charge amount of the toner in an environment from high temperature and high humidity to low temperature and low humidity may become large. If the amount is more than 10 parts by mass, the charge amount may be lowered.

  As the colorant used in the present invention, known pigments and dyes can be used alone or in combination. For example, as the dye, C.I. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I. I. Modern Tread 30, C.I. I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Acid Blue 9, C.I. I. Acid Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Modern Blue 7, C.I. I. Direct Green 6, C.I. I. Basic Green 4, C.I. I. Basic green 6 etc. are mentioned.

  The pigments include mineral fast yellow, navel yellow, naphthol yellow S, Hansa yellow G, permanent yellow NCG, tartrazine lake, molybdenum orange, permanent orange GTR, pyrazolone orange, benzidine orange G, permanent red 4R, and watching red calcium salt. , Eosin Lake, Brilliant Carmine 3B, Manganese Purple, Fast Violet B, Methyl Violet Lake, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue BC, Chrome Green, Pigment Green B, Malachite green lake, final yellow green G, etc. are mentioned.

  When used as a full-color image forming toner, the magenta color pigment includes C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 163, 202, 206, 207, 209, 238, C.I. I. Pigment violet 19, C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35, etc. are mentioned.

  Although such a pigment may be used alone, 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; 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, and 28 may be mentioned.

  Examples of the color pigment for cyan include C.I. I. Pigment Blue 2, 3, 15, 15: 1, 15: 2, 15: 3, 16, 17; I. Acid Blue 6; I. Examples thereof include Acid Blue 45 or a copper phthalocyanine pigment in which 1 to 5 phthalimidomethyl groups are 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, 93, 97, 155, 180, 185, C.I. I. Bat yellow 1, 3, 20 etc. are mentioned.

  As the black pigment, for example, carbon black such as furnace black, channel black, acetylene black, thermal black and lamp black is used, and magnetic powder such as magnetite and ferrite is also used. Furnace black having a high coloring power and a relatively high resistance is preferably used.

  In the case of a pigment, the amount of the colorant used is preferably 1 to 15 parts by weight, more preferably 3 to 12 parts by weight, and more preferably 4 to 10 parts by weight with respect to 100 parts by weight of the binder resin. More preferably. When the content of the colorant is more than 15 parts by mass, the transparency is lowered, and in addition, the reproducibility of intermediate colors as typified by human skin color is likely to be lowered, and further, the chargeability of the toner is stabilized. And the low-temperature fixability becomes difficult to obtain. When the content of the colorant is less than 1 part by mass, the coloring power is low, so that a large amount of toner must be used to obtain the density, the dot reproducibility is easily impaired, and a high-quality image with a high image density. Is difficult to obtain. In addition, when using magnetic powder as a black pigment, it is used in the range of 5 to 20 parts by mass with respect to 100 parts by mass of the binder resin.

  To the toner of the present invention, fine particles can be externally added for the purpose of improving toner transfer and transferability from the carrier and the photoreceptor. One of the external additives externally added to the toner particle surface is inorganic fine particles, and at least one of titanium oxide, alumina oxide, and silica is used. The average particle size (number of inorganic fine particles) The distribution peak value) is preferably 80 nm or more and 200 nm or less in order to function as spacer particles for improving toner separation from the carrier. The external additive is preferably used in combination with fine particles having an average particle diameter (peak value of number distribution) of 50 nm or less in order to improve the chargeability and fluidity of the toner. Further, it is preferable to subject the inorganic fine particles to a hydrophobic treatment. In the case of performing the hydrophobizing treatment, the hydrophobizing treatment is preferably performed using a so-called coupling agent such as various titanium coupling agents and silane coupling agents, silicone oil, or the like.

  Examples of surface treatment agents for hydrophobizing treatment include titanium coupling agents such as tetrabutyl titanate, tetraoctyl titanate, isopropyl triisostearoyl titanate, isopropyl tridecylbenzenesulfonyl titanate, bis (dioctyl pyrophosphate) oxy There is acetate titanate. Further, as silane coupling agents, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N-β- (N-vinylbenzylaminoethyl) γ-aminopropyltrimethoxysilane hydrochloride, hexamethyldisilazane, methyltrimethoxysilane, butyltrimethoxysilane, isobutyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltri Examples include methoxysilane, dodecyltrimethoxysilane, phenyltrimethoxysilane, o-methylphenyltrimethoxysilane, p-methylphenyltrimethoxysilane, and the like, and fatty acids and metal salts thereof include undecyl acid, Long chain fatty acids such as lauric acid, tridecylic acid, dodecylic acid, myristic acid, palmitic acid, pentadecylic acid, stearic acid, heptadecylic acid, arachidic acid, montanic acid, oleic acid, linoleic acid, arachidonic acid, and their metal salts Examples thereof include salts with metals such as zinc, iron, magnesium, aluminum, calcium, sodium, and lithium. Further, examples of the silicone oil include dimethyl silicone oil, methylphenyl silicone oil, and amino-modified silicone oil.

  These surface treatment agents are preferably added in an amount of 1 to 10% by mass based on the inorganic fine particles, and preferably 3 to 7% by mass. Further, these materials can be used in combination.

The degree of the hydrophobizing treatment is not particularly limited, but it is preferable to carry out the treatment so that the methanol wettability is 40 to 98. Methanol wettability is an evaluation of wettability to methanol. In this method, 0.2 g of inorganic fine particles to be measured is weighed and added to 50 ml of distilled water in a 200 ml beaker. Methanol is slowly dropped from a burette whose tip is immersed in a liquid, with slow stirring until the entire inorganic fine particles are wet. When the amount of methanol necessary to completely wet the inorganic fine particles is a (ml), the degree of hydrophobicity is calculated by the following formula. When measuring the degree of hydrophobicity in a high region, the measurement may be performed using a larger beaker as appropriate.
Hydrophobicity = (a / (a + 50)) × 100
The amount of the inorganic fine particles added is 0.1 to 5.0% by mass, preferably 0.5 to 4.0% by mass in the toner. In addition, various external additives may be used in combination.

  The photoreceptor of the present invention will be described.

Photosensitivity having an elastic deformation rate Wo of 46 to 65% and a HU (universal hardness value) of 1.5 × 10 ⁸ N / m ^{2 to} 2.3 × 10 ⁸ N / m ² when pushed in with a maximum load of 6 mN. In the case of using a body, a carrier having an average circularity C of 0.830 to 0.950 and a particle having (average circularity C-2σ) or less (σ is a standard deviation of carrier circularity) of 20% by number or less. By using in combination, it is possible to prevent the photoconductor from being scraped by the carrier, and to suppress the generation of fine scratches on the surface of the photoconductor and to have high durability. In order to further improve the characteristics, the elastic deformation rate Wo is more preferably 48 to 64%.
Although HU and elastic deformation rate Wo cannot be separated, for example, when HU exceeds 2.3 × 10 ⁸ N / m ² , or when friction with cleaning blade increases under high temperature, etc. In this case, if the elastic deformation rate Wo is less than 46%, the elastic force of the photosensitive member is insufficient. If the elastic deformation rate Wo is greater than 65%, the elastic deformation amount is small even if the elastic deformation rate is high. As a result, a large amount of pressure is locally applied to a small amount of carrier-adhered particles or externally added fine particles of 80 nm or more of fog toner, and deep scratches are generated. Therefore, it is considered that the one with a high HU is not necessarily optimal as the photosensitive member.

Further, when the HU is less than 1.5 × 10 ⁸ N / m ² and the elastic deformation rate Wo exceeds 65%, even if the elastic deformation rate is high, the amount of plastic deformation becomes large, which causes the cleaning blade and the charging roller to become large. The pinched paper powder and toner are rubbed and scraped or have fine scratches. Further, if the elastic deformation rate Wo is less than 46%, scratches are more likely to occur, resulting in poor durability.

  In order to satisfy the elastic deformation rate of the present invention, it can be achieved by selecting the material of the photoreceptor surface. Preferably, as will be described later, the material selection range of the charge transport layer is expanded and a protective layer for imparting strength is additionally used so that a material having a high charge mobility can be used as a charge transfer substance. It is preferable.

  The electrophotographic photosensitive member of the present invention is obtained by sequentially providing a charge generation layer and a charge transport layer on a support. Further, a protective layer may be provided on the outermost surface. Further, an undercoat layer for the purpose of preventing interference fringes or the like may be provided between the support and the charge generation layer.

  The support itself can be conductive, for example, aluminum, aluminum alloy, or stainless steel. In addition, aluminum, aluminum alloy, or indium oxide-tin oxide alloy is formed by vacuum deposition. The support having the layer formed, the plastic, the conductive fine particles (for example, carbon black, tin oxide, titanium oxide, silver particles, etc.) and the appropriate support resin impregnated into the plastic or paper, the conductive binder A plastic having a resin can be used.

  Further, a binder layer (adhesive layer) having a barrier function and an adhesive function can be provided between the support and the photosensitive layer. The binder layer is used to improve the adhesion of the photosensitive layer, improve the coatability, protect the support, cover defects on the support, improve the charge injection from the support, and protect against electrical breakdown of the photosensitive layer. It is formed. The binder layer can be formed of casein, polyvinyl alcohol, ethyl cellulose, ethylene-acrylic acid copolymer, polyamide, modified polyamide, polyurethane, gelatin, aluminum oxide, or the like. The thickness of the binder layer is preferably 5.0 μm or less, and particularly preferably 0.1 to 3.0 μm.

  Examples of the charge generating substance used in the present invention include (1) azo pigments such as monoazo, disazo and trisazo, (2) phthalocyanine pigments such as metal phthalocyanine and nonmetal phthalocyanine, and (3) indigo compounds such as indigo and thioindigo. Pigments, (4) perylene pigments such as perylene anhydride and perylene imide, (5) polycyclic quinone pigments such as anthraquinone and pyrenequinone, (6) squarylium dyes, (7) pyrylium salts and thiapyrylium salts ( 8) Triphenylmethane dyes, (9) inorganic substances such as selenium, selenium-tellurium and amorphous silicon, (10) quinacridone pigments, (11) azulenium salt pigments, (12) cyanine dyes, (13) xanthene dyes, 14) Quinone imine dye, (15) Su Lil dyes, and (16) cadmium sulfide and (17) zinc oxide.

  Examples of the binder resin used for the charge generation layer include polycarbonate resin, polyester resin, polyarylate resin, butyral resin, polystyrene resin, polyvinyl acetal resin, diallyl phthalate resin, acrylic resin, methacrylic resin, vinyl acetate resin, phenol resin, Examples thereof include, but are not limited to, silicone resins, polysulfone resins, styrene-butadiene copolymer resins, alkyd resins, epoxy resins, urea resins, and vinyl chloride-vinyl acetate copolymer resins. These can be used alone or as a mixture or as a copolymer polymer.

  The solvent used for the charge generation layer coating is selected from the solubility and dispersion stability of the resin used and the charge generation material, but examples of the organic solvent include alcohols, sulfoxides, ketones, ethers, esters, Aliphatic halogenated hydrocarbons or aromatic compounds can be used.

  The charge generation layer is well dispersed by a method such as a homogenizer, ultrasonic wave, ball mill, sand mill, attritor or roll mill, together with a binder resin and a solvent in an amount of 0.3 to 4 times the mass of the charge generation material, It is formed by coating and drying. The thickness is preferably 5.0 μm or less, and particularly preferably in the range of 0.01 to 1.0 μm.

  In addition, various sensitizers, antioxidants, ultraviolet absorbers, plasticizers, and known charge generating substances can be added to the charge generation layer as necessary.

  Examples of the binder resin used for forming the charge transport layer include acrylic resin, styrene resin, polyester, polycarbonate resin, polyarylate, polysulfone, polyphenylene oxide, epoxy resin, polyurethane resin, alkyd resin, and unsaturated resin. The resin chosen is preferred. Particularly preferred resins include polymethyl methacrylate, polystyrene, styrene-acrylonitrile copolymer, polycarbonate resin and diallyl phthalate resin.

  The charge transport materials used include various triarylamine compounds, various hydrazone compounds, various styryl compounds, various stilbene compounds, various pyrazoline compounds, various oxazole compounds, various thiazole compounds, and various triarylmethane compounds. Compound etc. are mentioned.

  The charge transport layer is generally formed by dissolving the charge transport material and the binder resin in a solvent and applying them. The mixing ratio (mass ratio) of the charge transport material and the binder resin is about 2: 1 to 1: 2. Solvents include ketones such as acetone and methyl ethyl ketone, esters such as methyl acetate and ethyl acetate, aromatic hydrocarbons such as toluene and xylene, chlorinated hydrocarbons such as chlorobenzene, chloroform and carbon tetrachloride, tetrahydrofuran, Ethers such as dioxane are used. When this solution is applied, for example, a coating method such as a dip coating method, a spray coating method and a spinner coating method can be used, and drying is preferably 10 ° C to 200 ° C, more preferably 20 ° C to 150 ° C. The temperature is in the range of 5 minutes to 5 hours, and more preferably 10 minutes to 2 hours.

  The charge transport layer is electrically connected to the above-described charge generation layer, receives charge carriers injected from the charge generation layer in the presence of an electric field, and transports these charge carriers to the interface with the protective layer. It has a function. Since this charge transport layer has a limit to transport charge carriers, the film thickness cannot be increased more than necessary, but it is preferably 5 to 30 μm, particularly preferably 7 to 20 μm. Further, since the charge carriers are diffused and the film thickness is large, the charge on the surface of the photoreceptor is spread with respect to the latent image, and the dot reproducibility is poor. Therefore, the range of 7 to 15 μm is more preferable. .

  Furthermore, an antioxidant, an ultraviolet absorber, a plasticizer, and a known charge transport material can be added to the charge transport layer as necessary.

  Furthermore, it is preferable to provide a surface layer using a curable resin as a binder resin on the charge transport layer. As the surface layer, a second charge transport layer having a charge transport function (in this case, the first charge transport layer is referred to as a “first charge transport layer”) or substantially having a charge transport function. Provided in the form of no protective layer. By applying and curing the second charge transport layer or the protective layer, a photoconductor having an elastic deformation rate of 46 to 65% is completed.

  As the second charge transporting layer, a layer containing a compound obtained by polymerizing a hole transporting compound having two or more chain polymerizable functional groups in the same molecule as represented by the following chemical formula (A) is preferably used.

In the formula, A represents a hole transporting group. P ¹ and ^{P 2} represents a chain polymerizable functional group. P ¹ and P ² may be the same or different. Z represents an organic residue which may have a substituent. a, b, and d represent 0 or an integer of 1 or more, and a + b × d represents an integer of 2 or more. When a is 2 or more, P ¹ may be the same or different. When d is 2 or more, P ² may be the same or different. When b is 2 or more, Z and P ² are the same or different. May be.

  A in the above chemical formula (A) represents a hole transporting group and may be any group as long as it exhibits hole transportability, but those represented by the following general formula (B) are preferred.

In the formula, R ⁴ , R ⁵ and R ⁶ are optionally substituted C1-C10 alkyl groups such as methyl, ethyl, propyl and butyl groups, and optionally substituted benzyl groups. A phenyl group, naphthyl group, anthryl group, phenanthryl group, pyrenyl group, thiophenyl group, furyl group, pyridyl group, which may have an aralkyl group and a substituent such as a phenethyl group, a naphthylmethyl group, a furfuryl group, and a thienyl group, An aryl group such as a quinolyl group, a benzoquinolyl group, a galvazolyl group, a phenothiazinyl group, a benzofuryl group, a benzothiophenyl group, a dibenzofuryl group, and a dibenzothiophenyl group.

Provided ^that at least two of the R 4, ^{R 5} and ^{R 6} represents an aryl ^group, R 4, ^{R 5} and ^{R 6} may each be the same or different.

Z in the chemical formula (a) is an alkylene group which may have a substituent, an arylene group which may have a substituent, CR ¹ = CR ² (R ¹ and R ² are an alkyl group, an aryl group, and A hydrogen atom, R ¹ and R ² may be the same or different), one selected from C═O, S═O, SO ₂ , an oxygen atom and a sulfur atom, or any combination thereof Indicates.

  Next, the chain polymerizable functional group in the present invention will be described. The chain polymerization in the present invention refers to the former polymerization reaction mode when the polymer formation reaction is largely divided into chain polymerization and sequential polymerization. For details, see, for example, “Basic Chemistry Resin Chemistry” by Tadahiro Miwa. (New Edition) ”July 25, 1995 (1 edition, 8 prints) As described in FIG. 24, it means unsaturated polymerization, ring-opening polymerization, isomerization polymerization, etc. in which the reaction proceeds mainly via intermediates such as radicals or ions.

  The chain-polymerizable functional group P in the chemical formula (A) means a functional group capable of the above-described reaction form, and a preferable one in the present invention is represented by the following structural formula (1).

[E is a hydrogen atom, a halogen atom, an alkyl group which may have a substituent and an aryl group which may have a substituent, a cyano group, a nitro group, an alkoxy group, —COOR ¹ (R ¹ is a hydrogen atom, A halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent and an aryl group which may have a substituent, CONR ² R ⁸ (where R ² and R ⁸ are hydrogen atoms) , A halogen atom, an alkyl group that may have a substituent, an aralkyl group that may have a substituent, and an aryl group that may have a substituent, which may be the same or different W represents a divalent arylene group which may have a substituent or a divalent alkylene group which may have a substituent, -COO-, -C-, -O-, -OO-, ^{-S -, - CONR 4 - (} R 4 is a hydrogen atom, halo A gen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent, or an aryl group which may have a substituent. f represents 0 or 1; ]

  Furthermore, a particularly preferable form of the chain polymerizable functional group P in the chemical formula (A) is shown below.

  By polymerizing a hole transporting compound having two or more chain polymerizable functional groups in the same molecule, in the second charge transporting layer, the compound having a hole transporting ability is at least two or more crosslinks. It is incorporated into the three-dimensional cross-linked structure with a point through a covalent bond. The hole transporting compound can be either polymerized alone or mixed with a compound having another chain polymerizable group, and the kind / ratio is arbitrary. As used herein, the compound having another chain polymerizable group includes any monomer or oligomer / polymer having a chain polymerizable group. When the functional group of the hole transporting compound and the functional group of the other chain polymerizable compound are the same group or a group that can be polymerized with each other, they both take a copolymerized three-dimensional crosslinked structure via a covalent bond. Is possible. When both functional groups are functional groups that do not polymerize with each other, the photosensitive layer is a mixture of at least two or more three-dimensional cured products or other chain-polymerizable compound monomers in the three-dimensional cured product as a main component. Although it is configured as a product containing the cured product, it can also have strength and toughness by forming an IPN (Inter Penetrating Network), that is, an interpenetrating network structure, by controlling the blending ratio / film forming method well. It is.

  In the present invention, a charge transport material can be contained in the second charge transport layer containing the cured product of the hole transport compound having a chain polymerizable group.

  When forming a protective layer containing no charge transport material on the surface layer, it is preferable to contain a film-forming resin such as a polycarbonate resin, a polyarylate resin, a polystyrene resin and a polymethyl methacrylate resin. The film thickness at this time is preferably 1.0 to 20.0 μm, and particularly preferably 5.0 to 15.0 μm.

  In the present invention, the second charge transport layer and the protective layer contain at least one selected from the group consisting of a fluorine atom-containing resin, a carbon fluoride, and a polyolefin resin as a lubricant. The thing is mentioned. However, it is not limited to these compounds.

  Preferred as the fluorine atom-containing resin is a polymer or copolymer resin of a compound selected from vinyl fluoride, vinylidene fluoride, chlorotrifluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoropropylene, perfluoroalkyl vinyl ether, and Examples include resin fine particles.

Examples of carbon fluoride include compounds represented by (CF) _n and (C ₂ F) _n .

  Preferred examples of the polyolefin resin include homopolymer resins such as polyethylene resin, polypropylene resin and polybutene resin, copolymer resins such as ethylene-propylene copolymer and ethylene-butene copolymer, and resin powder.

  These lubricants can be used alone or in combination of two or more at any ratio.

  Further, the second charge transport layer and the protective layer may contain a dispersant for the lubricant, a dispersion aid, other various additives, a surfactant, and the like.

  By including at least one of fluorine atom-containing resin, carbon fluoride, and polyolefin resin as a lubricant in the second charge transport layer and the protective layer, the surface slipperiness and water repellency of the photoreceptor can be improved. Prevents deterioration of transfer efficiency and slipperiness due to chemical deterioration of the surface layer due to charging, development, transfer, etc. during repeated use, as well as deterioration of electrical characteristics such as sensitivity reduction and potential drop, and fineness even during repeated use. It is possible to prevent the occurrence of scratches and to suppress the occurrence of image defects such as image blur / flow. Particularly preferable results are obtained when the fluorine-containing resin is used.

  In the present invention, the ratio of the lubricant contained in the second charge transport layer and the protective layer is preferably 1 to 70%, more preferably 5 to 50%, with respect to the total mass of the layer serving as the surface layer. When the amount of the lubricant is more than 70%, the mechanical strength of the layer serving as the surface layer tends to be lowered, and when it is less than 1%, the water repellency and slipperiness of the layer serving as the surface layer may not be sufficient.

  The second charge transport layer is generally formed by applying a polymerization reaction after applying the solution containing the hole transporting compound, but reacting the solution containing the hole transporting compound in advance. Then, after obtaining a cured product, it can be formed again by dispersing or dissolving in a solvent. As a method for applying these solutions, for example, a dip coating method, a spray coating method, a curtain coating method, a spin coating method, and the like are known, but the dip coating method is preferable from the viewpoint of efficiency / productivity.

  The second charge transport layer is preferably cured by a polymerization reaction using heat, ultraviolet light, electron beam, etc., but in view of productivity, energy efficiency, etc., it is cured by the method described below. It is preferable.

  In the present invention, the hole transporting compound having a chain polymerizable group is preferably polymerized by radiation. The greatest advantage of polymerization by radiation is that a polymerization initiator is not required, which makes it possible to produce a very high-purity three-dimensional photosensitive layer and to ensure good electrophotographic characteristics. In addition, because it is a short and efficient polymerization reaction, it is highly productive, and because of its high radiation permeability, it inhibits curing when thick films and additives such as additives are present in the film. The influence of the is very small. However, depending on the type of the chain polymerizable group and the type of the central skeleton, the polymerization reaction may not easily proceed, and in this case, it is possible to add a polymerization initiator within a range that does not affect the reaction. The radiation used at this time is an electron beam and a gamma ray. In the case of electron beam irradiation, any type of accelerator such as a scanning type, an electro curtain type, a broad beam type, a pulse type, and a laminar type can be used. When irradiating with an electron beam, the irradiation conditions are very important in the photoreceptor of the present invention in order to develop electric characteristics and durability. In the present invention, the acceleration voltage is preferably 250 kV or less, and optimally 150 kV or less. The dose is preferably in the range of 10 kGy to 1000 kGy. When the accelerating voltage exceeds the above, the electron beam irradiation damage tends to increase on the photoreceptor characteristics. Further, when the dose is less than the above range, the curing tends to be insufficient, and when the dose is large, the photoreceptor characteristics are likely to be deteriorated.

  The second charge transport layer and the protective layer diffuse charge carriers and may be inferior in dot reproducibility. Therefore, the film thickness cannot be increased, but is preferably 0.5 to 10.0 μm. A range of 0 to 6.0 μm is preferable.

  The photoreceptor according to the present invention is a thin film photoreceptor, and the charge transport layer has a thickness of 8.0 to 20.0 μm. More preferably, it is 8.0-16.0 micrometers, More preferably, it is 8.0-12.0 micrometers. This layer thickness is the total layer thickness of the first charge transport layer and the second charge transport layer when the second charge transport layer is provided.

  Further, the total layer thickness as the photoreceptor is preferably 10.0 to 40.0 μm, and the total layer thickness is preferably 10.0 to 26.0 μm in order to achieve both dot reproducibility and durability suitably.

  A suitable method for measuring physical properties related to the present invention will be described below.

<Measurement of toner particle size distribution>
As a measuring device, a Coulter Counter TA-II or Coulter Multisizer II (manufactured by Beckman Coulter, Inc.) is used. As the electrolytic solution, an about 1% NaCl aqueous solution is used. As the electrolytic solution, an electrolytic solution prepared using primary sodium chloride, for example, ISOTON-II (registered trademark) (manufactured by Coulter Scientific Japan) can be used.

  As a measurement method, 0.1 to 5 ml of a surfactant (preferably alkylbenzenesulfone hydrochloric acid) 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 electrolyte solution in which the sample is suspended is dispersed for about 1 to 3 minutes with an ultrasonic disperser, and the volume and number of the sample are measured for each channel with the measuring device using a 100 μm aperture as the aperture. The volume distribution and the number distribution are calculated. From these obtained distributions, the weight average particle diameter (D4) of the sample is determined. 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 32-40.30 μm are used.

<Measurement of average circularity of toner>
The circularity of the toner is measured using a flow type particle image measuring device “FPIA-2100 type” (manufactured by Sysmex Corporation), and is calculated using the following equation.

  Here, the “particle projected area” is the area of the binarized toner image, and the “peripheral length of the particle projected image” is defined as the length of the contour line obtained by connecting the edge points of the toner image. . The measurement uses the perimeter of the particle image when image processing is performed at an image processing resolution of 512 × 512 (pixels of 0.3 μm × 0.3 μm).

  In the present invention, the degree of circularity is an index indicating the degree of unevenness of particles, and is 1.00 when the particles are perfectly spherical. The more complicated the surface shape, the smaller the degree of circularity.

  The average circularity T, which means the average value of the circularity frequency distribution, is calculated from the following equation, where ti is the circularity (center value) at the dividing point i of the particle size distribution and m is the number of measured particles.

  In addition, “FPIA-2100”, which is a measuring apparatus used in the present invention, calculates the circularity of each particle, and then calculates the average circularity. 1.00 is divided into classes equally divided every 0.01, and the average circularity T is calculated using the center value of the division points and the number of measured particles.

  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 “Tetora 150 type” (manufactured by Nikka Ki Bios Co., Ltd.) is used, and dispersion treatment 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. In order to suppress variation in circularity, the installation environment of the apparatus is controlled at 23 ° C. ± 0.5 ° C. so that the temperature inside the flow type particle image analyzer FPIA-2100 is 26 to 27 ° C. Preferably, autofocus is performed using 2 μm latex particles every 2 hours.

  To measure the circularity of the toner, the flow type particle image measuring device is used, the concentration of the dispersion is readjusted so that the toner concentration at the time of measurement is 3000 to 10,000 / μl, and 1000 or more toners are measured. To do. After the measurement, data having an equivalent circle diameter of less than 2 μm is cut using this data, and the average circularity T of the toner is obtained.

  Furthermore, “FPIA-2100”, which is a measuring apparatus used in the present invention, improves the magnification of the processed particle image as compared with “FPIA-1000” conventionally used for calculating the shape of the toner. Furthermore, the accuracy of toner shape measurement is improved by improving the processing resolution of the captured image (256 × 256 → 512 × 512), thereby achieving more reliable capture of fine particles. Therefore, when it is necessary to measure the shape more accurately as in the present invention, the FPIA-2100 that can obtain information on the shape more accurately is more useful.

<Measurement of molecular weight by GPC (binder resin for toner, resin for forming coat layer)>
The molecular weight of the chromatogram by gel permeation chromatograph (GPC) is measured under the following conditions.

Resin adjusted to 0.05 to 0.6% by mass as a sample concentration by stabilizing the column in a heat chamber at 40 ° C., and flowing tetrahydrofuran (THF) as a solvent at a flow rate of 1 ml / min. Measurement is performed by injecting 50 to 200 μl of a THF sample solution. An RI (refractive index) detector is used as the detector. The column, in order to accurately measure the ¹⁰ 3 to 2 × 10 ⁶ molecular weight region of good combination of several commercially available polystyrene gel column, e.g., made of Waters Co. μ-styragel 500,10 ^3, 10 ⁴ A combination of 10 ^{5 or} a combination of shodex KA-801, 802, 803, 804, 805, 806, 807 manufactured by Showa Denko KK is preferred.

In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical Co. Manufactured by Toyo Soda Kogyo Co., Ltd., with molecular weights of 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , It is appropriate to use 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ , and use at least about 10 standard polystyrene samples.

  The resin for forming the coating layer is obtained by putting carrier particles in methyl ethyl ketone so as to have a concentration of 10% by mass, and performing a dispersion treatment for 2 minutes using an ultrasonic disperser “Tetora 150 type” (manufactured by Nikka Ki Bios). The filtrate obtained by filtering through a membrane filter having an opening of 0.2 μm is used.

<Measurement of maximum endothermic peak of release agent and toner>
The maximum endothermic peak of the release agent and toner can be measured according to ASTM D3418-82 using a differential thermal analyzer (DSC measuring device) and DSC2920 (TA Instruments Japan).
Temperature curve: Temperature increase I (30 ° C. to 200 ° C., temperature increase rate 10 ° C./min)
Temperature drop I (200 ° C-30 ° C, temperature drop rate 10 ° C / min)
Temperature increase II (30 ° C. to 200 ° C., temperature increase rate 10 ° C./min)

  As a measuring method, 5 to 20 mg, preferably 10 mg of a measurement sample is accurately weighed. This is put into an aluminum pan, and an empty aluminum pan is used as a reference, and measurement is performed at a temperature rise rate of 10 ° C./min and normal temperature and humidity in a measurement temperature range of 30 to 200 ° C. The maximum endothermic peak of the toner is determined in the process of temperature increase II, the one having the highest height from the baseline in the region above the endothermic peak of the resin Tg, or the endothermic peak of the resin Tg overlaps with another endothermic peak. If this is difficult, the maximum endothermic peak of the toner of the present invention is defined as the highest peak from the maximum peak of the overlapping peaks.

<Measurement of particle diameter of inorganic fine particles and external additives of toner>
Regarding the particle size of inorganic fine particles and external additives on the toner surface, 500 or more particles having a particle size of 5 nm or more are randomly extracted with a scanning electron microscope (50,000 times), and the major axis and minor axis are measured with a digitizer. The average particle size is defined as the particle size distribution of 500 or more particles (column widths of 5-15, 15-25, 25-35, 35-45, 45-55, 55-65, 65-75). , 75-85, 85-95,... (From the column histogram divided every 10 nm), the particle diameter at the peak of the center value of the column is calculated as the maximum peak particle diameter of the inorganic fine particles.

<Measurement of carrier particle size>
The particle size of the magnetic carrier particles is measured by a dry method using a particle size distribution measuring device using a method of detecting a light intensity distribution pattern such as a laser diffraction particle size distribution measuring device. Any device can be used as long as the measuring range can measure a range from submicron to several hundreds of microns. For example, the volume average particle size (Dv) is calculated by measuring using SALD-3100 (manufactured by Shimadzu Corporation). To do.

<Measurement of Average Circularity C and Standard Deviation σ Based on Number of Carriers>
For the average circularity C of the carrier, the number-based average circularity C is calculated using a multi-image analyzer (manufactured by Beckman Coulter). In the measurement, a mixed solution of about 1% NaCl aqueous solution and glycerin 50% by volume: 50% by volume is used as the electrolytic solution. For the preparation of the electrolytic solution, an electrolytic solution prepared using primary sodium chloride, for example, ISOTON-II (registered trademark) (manufactured by Coulter Scientific Japan Co., Ltd.) can be used. As glycerin, a special grade or first grade reagent can be used. As a dispersant, 0.1 to 1.0 ml of a surfactant (preferably alkylbenzenesulfone hydrochloride) is added to about 30 ml of an 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 minute, and an equivalent circle diameter and circularity C are calculated by the measuring apparatus using a 200 μm aperture and a lens 20 times as an aperture. . The conditions for the measurement are as follows.
Average luminance within measurement frame: 220 to 230
Measurement frame setting: 300
SH (threshold): 50
Binarization level: 180

  In the measurement, an electrolytic solution-glycerin mixed solution is put in a glass measuring container, and the sample shown above is put therein so that the concentration becomes 5 to 10%, and stirred at the maximum stirring speed. The sample suction pressure is 10 kPa. Since the carrier specific gravity is large and the sedimentation is easy, the measurement time is set to 15 to 30 minutes. Further, the measurement is interrupted every 5 to 10 minutes to replenish the sample solution and the electrolytic solution-glycerin mixed solution. Restart measurement after refilling. The number of measurements is 2000. After the measurement is finished, the main body software removes a defocused image, aggregated particles (multiple simultaneous measurements), etc. on the particle image screen. The measurement principle of this device is to ignite a strobe with a current pulse generated when particles in Coulter Multisizer II pass through the aperture as a trigger, record the projected image with a CCD, and perform image analysis processing. Since the plot on the obtained graph and the particle image photograph correspond to 1: 1, it is possible to remove defocused or aggregated particles as described above.

The circularity of the carrier and the equivalent circle diameter are calculated by the following equations.
Circularity = (4 × Area) / (MaxLength ² × π)
Equivalent circle diameter = 2 × (Area / π) ^1/2
Here, “Area” is the projected area of the binarized carrier particle image, and “MaxLength” is defined as the maximum diameter of the carrier particle projected image. The equivalent circle diameter is represented by the diameter of a perfect circle when “Area” is the area of the perfect circle. The equivalent circle diameter is divided into 256 parts of 4 to 100 μm and is used logarithmically based on the number. FIG. 5 shows a diagram of actual measurement results. The horizontal axis is the equivalent circle diameter, the left axis displays the number-based particle size frequency (%) as a bar graph, and the right axis displays the circularity in dots. (Average circularity C-2σ) is calculated from the average circularity C and standard deviation σ determined by the main body software, and the number of particles having a circularity of (average circularity C-2σ) or less is determined from the graph, The abundance ratio is obtained by dividing by the number of particles. These series of measurements and calculations are processed in the software attached to the multi-image analyzer.

<Measurement of particle diameter of magnetic substance, nonmagnetic inorganic compound, etc. in carrier>
The particle size of the magnetic material and non-magnetic inorganic compound is obtained by extracting 300 or more particles having a particle size of 5 nm or more at random from a cross section obtained by cutting the carrier with a microtome or the like using a scanning electron microscope (50,000 times). The axis and minor axis are measured with a digitizer, and the average is taken as the particle size, and the particle size distribution of 300 or more particles (column width is 5-15, 15-25, 25-35, 35-45, 45-55 , 55-65, 65-75, 75-85, 85-95,... (From the column histogram divided every 10 nm) calculate.

  In addition, as a method of measuring the particle size of the magnetic substance and the non-magnetic inorganic compound, the average particle size is determined in the same manner as the above method from the photograph of the raw material with a transmission electron microscope (TEM) at a magnification of 50,000 times. You can ask for it.

<Measurement of particle size of fine particles in carrier coat resin>
The particle size of the fine particles is 500 or more random particles having a particle size of 5 nm or more by scanning electron microscope (50,000 times) obtained by dissolving a coating material from a carrier in a solvent such as toluene. The major axis and the minor axis are extracted with a digitizer, and the average is taken as the particle size. The particle size distribution of 500 or more particles (column width is 5-15, 15-25, 25-35, 35-45). , 45-55, 55-65, 65-75, 75-85, 85-95, etc. (from the histogram of the column divided every 10 nm) The peak particle size is calculated.

  In addition, as a method for measuring the particle size of the fine particles in the carrier, the average particle size may be obtained in the same manner as in the above method from a photograph taken at 50,000 times the raw material with a transmission electron microscope (TEM). I can do it.

<Measurement of magnetization of carrier>
The strength of magnetization of the carrier can be measured using an oscillating magnetic field type magnetic property automatic recording apparatus BHV-30 manufactured by Riken Denshi Co., Ltd. As a measurement method, a cylindrical plastic container was filled with a carrier so as to be sufficiently dense, while an external magnetic field of 79.6 (kA / m) (1000 oersted) was created, and the container was filled in this state. Measure the magnetization moment of the carrier. Further, the actual mass of the carrier filled in the container is measured to determine the magnetization strength (Am2 / kg) of the carrier. Furthermore, the strength of magnetization per carrier volume (kAm ² / m ³ ) can be obtained by multiplying the obtained value by the true specific gravity (g / cm ³ ) of the carrier.

<Measurement of true specific gravity of carrier>
The true specific gravity of the carrier particles can be determined by a dry automatic densimeter autopycnometer (manufactured by Yuasa Ionics).

<Measurement of resistivity of carrier, nonmagnetic inorganic compound and magnetic substance>
The specific resistance values of the magnetic carrier, the nonmagnetic inorganic compound, and the magnetic material are measured using the measuring apparatus shown in FIG. The cell E is filled with sample particles, and the lower electrode 61 and the upper electrode 62 are arranged so as to be in contact with the filled particles, and the voltage is decreased at intervals of 200 V from 1000 V to 200 V every 30 seconds by a constant voltage device 66 between these electrodes. A method is used in which a specific resistance is obtained by applying a voltage while measuring the current flowing at each time with an ammeter 64. The measurement conditions of the specific resistance in the present invention are a contact area S between the filled carrier particles and the electrode of about 2.4 cm ² , a thickness L = 0.2 mm, and a load of the upper electrode 62 of 180 g. Each of the resistance values at 1000 V to 200 V is plotted, and a specific resistance value of 4000 V / cm is obtained from the profile to obtain a specific resistance. In addition, 63 shows an insulator, 65 shows a voltmeter, 68 shows a guide ring, E shows a resistance measurement cell.

<Method for measuring physical properties of photoreceptor surface>
After leaving the photoreceptor in an environment of 25 ° C. and 50% humidity for 24 hours, HU and elastic deformation rate Wo are determined using the above-described microhardness measuring device Fischerscope H100V (Fischer).

  The HU (universal hardness value) and elastic deformation rate Wo in the present invention are the microhardness measuring device Fischer that continuously applies a load to the indenter and directly reads the indentation depth under the load to obtain the continuous hardness. Measurement is performed using a scope H100V (Fischer). As the indenter, a Vickers square pyramid diamond indenter having a facing angle of 136 ° is used. Load conditions are measured stepwise up to a final load of 6 mN (273 points with a holding time of 0.1 s for each point).

  An outline of the output chart is shown in FIG. The vertical axis represents the load (mN) and the horizontal axis represents the indentation depth h (μm), which is the result of increasing the load stepwise and applying the load to 6 mN, and then decreasing the load stepwise similarly.

  HU (universal hardness value: hereinafter referred to as HU) is defined by the following formula (1) from the indentation depth under the same load when indented at 6 mN.

The elastic deformation rate Wo is obtained from the work (energy) performed by the indenter on the membrane, that is, the change in energy due to the increase or decrease in the load of the indenter on the membrane, and the value can be obtained from the following equation (2). The total work Wt (nW) is represented by an area surrounded by A-B-D-A in FIG. 6, and the elastic deformation work We (nW) is represented by an area surrounded by C-B-D-C. Is done.
Elastic deformation rate Wo (%) = (We / Wt) × 100 (2)

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

(Carrier Production Example A)
Magnetite powder having a number average particle diameter of 250 nm and a specific resistance of 5.1 × 10 ⁵ Ω · cm (magnetization strength of 64 Am ² / kg at 79.6 kA / m, true specific gravity of 5.2 g / cm ³ ), number average particle diameter Hematite powder (nonmagnetic, true specific gravity 5.1 g / cm ³ ) having a specific resistance of 4.9 × 10 ⁷ Ω · cm at 260 nm and 4.0% by mass of a silane coupling agent (3- (2-aminoethyl) Aminopropyl) trimethoxysilane) was added, and the mixture was surface-treated by mixing and stirring at 110 ° C. in a container at high speed.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 37% by weight aqueous solution) 6 parts by mass-Treated magnetite fine particles 76 parts by mass-Treated hematite fine particles 8 parts by mass The above materials, 28 mass% ammonia water 5 parts by mass, water Ten parts by mass were placed in a flask and mixed well. The amount of dissolved oxygen in the reaction medium at this time was 7.3 g / m ³ . Nitrogen gas was then introduced into the reaction medium. Nitrogen gas was introduced at a flow rate of 1.5 × 10 ⁻² m ³ / h for 20 minutes. Moreover, the amount of dissolved oxygen in the reaction medium at this time was 1.0 g / m ³ . Thereafter, the amount of nitrogen introduced was suppressed to 0.3 × 10 ⁻² m ³ / h, heated from room temperature at an average rate of temperature increase of 3.0 ° C./min, heated to 85 ° C. with stirring, and polymerized for 3 hours. Reacted and cured. The stirring blade peripheral speed at this time was 1.8 m / sec. Then, after cooling to 30 ° C. and further adding water, the supernatant was removed, and the precipitate was washed with water and then air-dried. Subsequently, this was dried under reduced pressure (5 hPa or less) at a temperature of 60 ° C. to obtain a spherical magnetic carrier core (a) having a volume average particle diameter of 35.1 μm in which a magnetic material was dispersed.

  3 parts by mass of a methyl methacrylate macromonomer having an ethylenically unsaturated group at one end and having a weight average molecular weight of 5,000, 25 parts by mass of the monomer shown in the following Compound Example 1, and 72 parts by mass of methyl methacrylate were added to a reflux condenser, temperature This was added to a four-necked flask equipped with a total, a nitrogen suction tube and a mixing type stirring device, and further 100 parts by mass of toluene, 100 parts by mass of methyl ethyl ketone, 2.4 parts by mass of azobisisovaleronitrile were added, and the mixture was heated at 80 ° C. under a nitrogen stream. For 10 hours to obtain a graft copolymer solution (solid content: 33% by mass). The weight average molecular weight according to gel permeation chromatogram (GPC) of the graft copolymer was 22,000.

0.5 parts by mass of crosslinked melamine resin particles (number average particle size 230 nm), carbon black (number average particle size 30 nm, DBP oil absorption 40 ml / 100 g) with respect to 30 parts by mass of the graft copolymer solution (solid content 33% by mass) ) 1.0 part by mass and 100 parts by mass of toluene are mixed well by a homogenizer. Next, with respect to 1000 parts by mass of the magnetic carrier core (a), the above coating solution was gradually added while stirring while continuously applying shear stress using a vacuum degassing kneader, and the solvent was volatilized at 70 ° C. Then, resin coating was performed on the carrier surface. The resin-coated magnetic carrier particles were heat-treated while stirring at 100 ° C. for 2 hours under the condition of nitrogen introduction amount of 0.3 × 10 ⁻² m ³ / h, cooled, crushed, and sieved with an opening of 76 μm. The coarse particles were removed with a volume average particle size of 35.3 μm, a true specific gravity of 3.63 g / cm ³ , a magnetization strength of 191 kAm ² / m ³ , a specific resistance of 6.2 × 10 ⁸ Ω · cm, and an average circularity. Carrier A having 2.1% by number of particles having a circularity of C of 0.922, standard deviation σ of 0.028, and (average circularity C−2σ) = 0.866 or less was obtained. Most of the obtained carriers were spherical to elliptical, and there were very few amorphous particles.

(Carrier Production Example B)
Magnetite powder having a number average particle diameter of 250 nm and a specific resistance of 5.1 × 10 ⁵ Ω · cm (magnetization strength of 64 Am ² / kg at 79.6 kA / m, true specific gravity of 5.2 g / cm ³ ), number average particle diameter Hematite powder (non-magnetic, true specific gravity 5.3 g / cm ³ ) having a specific resistance of 1.3 × 10 ⁸ Ω · cm and a silane coupling agent (4.0% by mass and 0.8% by mass, respectively) -(2-aminoethylaminopropyl) trimethoxysilane) was added, and the mixture was subjected to surface treatment by high-speed mixing and stirring at 110 ° C. in a container.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 37% by weight aqueous solution) 6 parts by mass-The above treated magnetite fine particles 60 parts by mass-The above treated hematite fine particles 24 parts by mass The above materials, 5% by mass 28% ammonia water, water Ten parts by mass were placed in a flask and mixed well. At this time, the amount of dissolved oxygen in the reaction medium was 7.4 g / m ³ . Nitrogen gas was then introduced into the reaction medium. Nitrogen gas was introduced at a flow rate of 1.5 × 10 ⁻² m ³ / h for 20 minutes. Moreover, the amount of dissolved oxygen in the reaction medium at this time was 1.2 g / m ³ . Thereafter, the amount of nitrogen introduced was suppressed to 0.3 × 10 ⁻² m ³ / h, heated from room temperature at an average rate of temperature increase of 3.0 ° C./min, heated to 85 ° C. with stirring, and polymerized for 3 hours. Reacted and cured. In the same manner as the magnetic carrier core (a), a spherical magnetic carrier core (b) having a volume average particle size of 36.7 μm in which a magnetic material was dispersed was obtained.

The magnetic carrier core (b) is coated with the same formulation as the carrier A, and has a volume average particle size of 37.2 μm, a true specific gravity of 3.56 g / cm ³ , a magnetization strength of 148 kAm ² / m ³ , and a specific resistance of 7.3. × 10 ¹¹ Ω · cm, average circularity C is 0.896, standard deviation σ is 0.054, (average circularity C−2σ) = 0.788 or less abundance of particles having a circularity of 5.3 or less A number% carrier B was obtained. Most of the obtained carriers had a spherical shape to an elliptical shape, and a long and narrow elliptical shape was observed, and there were very few amorphous particles.

(Carrier Production Example C)
Magnetite powder having a number average particle size of 250 nm and a specific resistance of 5.1 × 10 ⁵ Ω · cm (magnetization strength at 79.6 kA / m of 65 Am ² / kg, true specific gravity of 5.2 g / cm ³ ), number average particle size Hematite powder (nonmagnetic, true specific gravity 5.1 g / cm ³ ) having a specific resistance of 4.9 × 10 ⁷ Ω · cm at 260 nm and a titanium coupling agent isopropyltri (N-aminoethyl- Aminoethyl) titanate was added, and the mixture was stirred and mixed at 110 ° C. in a container at a high speed for surface treatment.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 37% by weight aqueous solution) 6 parts by mass-The above treated magnetite fine particles 76 parts by mass-The above treated hematite fine particles 8 parts by mass The above materials, 28 parts by mass ammonia water 6 parts by mass, water 8 parts by mass were placed in a flask and mixed well. The amount of dissolved oxygen in the reaction medium at this time was 6.5 g / m ³ . Nitrogen gas was then introduced into the reaction medium. Nitrogen gas was introduced at a flow rate of 1.5 × 10 ⁻² m ³ / h for 20 minutes. Moreover, the amount of dissolved oxygen in the reaction medium at this time was 1.1 g / m ³ . Thereafter, the amount of nitrogen introduced was suppressed to 0.3 × 10 ⁻² m ³ / h, heated from room temperature at an average rate of temperature increase of 3.0 ° C./min, heated to 85 ° C. with stirring, and polymerized for 3 hours. Reacted and cured. The stirring blade peripheral speed at this time was 1.2 m / sec. Then, after cooling to 30 ° C. and further adding water, the supernatant was removed, and the precipitate was washed with water and then air-dried. Subsequently, this was dried under reduced pressure (5 hPa or less) at a temperature of 60 ° C. to obtain a spherical magnetic carrier core (c) having a volume average particle diameter of 52.7 μm in a state where the magnetic material was dispersed.

For 20 parts by mass of the graft copolymer solution (solid content 33% by mass) used in Carrier A, 0.3 parts by mass of crosslinked melamine resin particles (number average particle size 200 nm), carbon black (number average particle size 30 nm, DBP Oil absorption 40 ml / 100 g) 0.6 parts by mass and 100 parts by mass of toluene are mixed well by a homogenizer. Subsequently, 1000 parts by mass of the magnetic carrier core (c) was stirred while continuously applying shear stress, and the above coating solution was gradually added to evaporate the solvent at 70 ° C. to coat the resin on the carrier surface. . A volume average particle diameter of 53.2 μm, a true specific gravity of 3.63 g / cm ³ , a magnetization strength of 194 kAm ² / m ³ , a specific resistance of 2.9 × 10 ⁹ Ω · cm, an average circle A carrier C having a degree C of 0.902, a standard deviation of σ of 0.053, and an abundance of particles having a degree of circularity of (average circularity C-2σ) = 0.996 or less is 5.8% by number is obtained. . Most of the obtained carriers had a spherical shape to an elliptical shape, a slightly elongated elliptical shape was seen, and irregular particles were present on the fine powder side.

(Carrier Production Example D)
A magnetite powder having a number average particle size of 220 nm is calcined in air at 700 ° C. for 3 hours and magnetite powder having a number average particle size of 220 nm and a specific resistance of 8.5 × 10 ⁷ Ω · cm (magnetization strength at 79.6 kA / m). 57 Am ² / kg, true specific gravity 5.1 g / cm ³ ). Thereafter, 4.0% by mass of a silane coupling agent (3- (2-aminoethylaminopropyl) trimethoxysilane) was added, and the mixture was surface-treated by mixing and stirring at 120 ° C. in a container.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 37% by weight aqueous solution) 6 parts by weight-Treated magnetite 84 parts by weight The above materials, 28 parts by weight ammonia water 4 parts by weight and water 12 parts by weight are placed in a flask and mixed well did. At this time, the amount of dissolved oxygen in the reaction medium was 7.4 g / m ³ . Nitrogen gas was then introduced into the reaction medium. Nitrogen gas was introduced at a flow rate of 1.5 × 10 ⁻² m ³ / h for 20 minutes. Moreover, the amount of dissolved oxygen in the reaction medium at this time was 0.88 g / m ³ . Thereafter, the amount of nitrogen introduced was suppressed to 0.3 × 10 ⁻² m ³ / h, heated from room temperature at an average rate of temperature increase of 3.0 ° C./min, heated to 85 ° C. with stirring, and polymerized for 3 hours. Reacted and cured. The stirring blade peripheral speed at this time was 2.4 m / sec. Then, after cooling to 30 ° C. and further adding water, the supernatant was removed, and the precipitate was washed with water and then air-dried. Subsequently, this was dried under reduced pressure (5 hPa or less) at a temperature of 60 ° C. to obtain a spherical magnetic carrier core (d) having a volume average particle diameter of 23.3 μm in a state where the magnetic material was dispersed.

  3 parts by mass of a methyl methacrylate macromonomer having an ethylenically unsaturated group at the terminal and having a weight average molecular weight of 5,000, 20 parts by mass of the monomer shown in the following Compound Example 2, 77 parts by mass of methyl methacrylate, a reflux condenser, thermometer, It is added to a four-necked flask equipped with a nitrogen suction tube and a mixing type stirring device, and further 100 parts by mass of toluene, 100 parts by mass of methyl ethyl ketone, 2.4 parts by mass of azobisisovaleronitrile are added, and the mixture is added at 80 ° C. under a nitrogen stream. While maintaining the time, a graft copolymer solution (solid content: 33% by mass) was obtained. The weight average molecular weight according to gel permeation chromatogram (GPC) of the graft copolymer was 21,000.

1.0 part by mass of spherical silica particles (number average particle size 300 nm), carbon black (number average particle size 30 nm, DBP oil absorption 40 ml) with respect to 50 parts by mass of the obtained graft copolymer solution (solid content 33% by mass) / 100g) 1.5 parts by mass and 100 parts by mass of toluene are mixed well by a homogenizer. Subsequently, 1000 parts by mass of the magnetic carrier core (d) was stirred while continuously applying a shear stress, and the coating solution was gradually added to evaporate the solvent at 70 ° C. to coat the surface of the carrier with a resin. . Volume average particle diameter 23.5 μm, true specific gravity 3.57 g / cm ³ , magnetization strength 187 kAm ² / m ³ , specific resistance 4.1 × 10 ⁹ Ω · cm, average circularity C 0.874, standard deviation Carrier D in which the abundance of particles having a circularity of σ of 0.052 and (average circularity C−2σ) = 0.770 is 2.8% by number was obtained. Some of the obtained carriers had a spherical shape, but most of them had an elliptical shape, and almost no amorphous particles were present.

(Carrier Production Example E)
Methanol was volatilized while applying 80 parts by mass of a 3% by mass methanol solution of γ-aminopropyltrimethoxysilane to the surface of 2000 parts by mass of the magnetic carrier core (c) while applying a shear stress.

  After diluting silicone resin SR2410 (manufactured by Toray Dow Corning Co., Ltd.) with 200 parts by mass of toluene so that the silicone resin solid content is 10% by mass, 8 parts by mass of γ-aminopropyltrimethoxysilane with respect to the silicone resin Further, 2 parts by mass of spherical silica particles (number average particle size 280 nm) were added and mixed well with a homogenizer to prepare a coating material solution.

While stirring at 50 ° C., the magnetic carrier core (c) treated with the silane coupling agent was added under reduced pressure, and the resin coating was performed with the coating material. Then, after the toluene was volatilized while stirring in an atmosphere of nitrogen gas for 2 hours while setting the amount of nitrogen introduced to 0.3 × 10 ⁻² m ³ / h, heat treatment was performed at 140 ° C. for 2 hours in an atmosphere of nitrogen gas. After cooling and crushing, coarse particles are removed with a sieve having an aperture of 76 μm, and a volume average particle size of 53.1 μm, a true specific gravity of 3.62 g / cm ³ , and a magnetization strength of 193 kAm ² / m ^3. , Specific resistance 9.9 × 10 ⁸ Ω · cm, average circularity C of 0.905, standard deviation σ of 0.051, (average circularity C−2σ) = 0.803 or less. Carrier E having an abundance ratio of 5.4% by number was obtained. Most of the obtained carriers had a spherical shape to an elliptical shape, and some irregular particles were present on the fine powder side.

(Carrier Production Example F)
In a 4-necked flask equipped with a reflux condenser, a thermometer, a nitrogen suction tube, and a rubbing method stirring apparatus, 10 parts by mass of polyvinyl alcohol was added to 1000 parts by mass of ion-exchanged water, and the mixture was stirred until completely dissolved. After mixing 33 parts by mass of cyclohexyl methacrylate monomer, 67 parts by mass of methyl methacrylate and 2 parts by mass of polymerization initiator 2,2′-azobis (2,4-dimethylvaleronitrile), the mixture was added to the flask, and the mixture was added at 80 ° C. under a nitrogen stream. For 10 hours to polymerize the graft copolymer. The obtained graft copolymer was dried under reduced pressure to obtain a solid. The weight average molecular weight according to gel permeation chromatogram (GPC) of the graft copolymer was 20,000.

The graft copolymer is diluted in toluene to a solid content of 33% by mass, 0.7 parts by mass of crosslinked melamine-formaldehyde resin particles (number average particle size 230 nm), carbon 1.0 part by weight of black (number average particle size 40 nm, DBP oil absorption 80 ml / 100 g) and 100 parts by weight of toluene are mixed well with a homogenizer. Next, 1000 parts by mass of the carrier core (c) was stirred while continuously applying shear stress, and the coating solution was gradually added to volatilize the solvent at 80 ° C. to coat the carrier surface with a resin. The resin-coated magnetic carrier particles were heat-treated with stirring at 120 ° C. for 2 hours with a nitrogen introduction amount of 0.3 × 10 ⁻² m ³ / h, cooled, crushed, and sieved with an opening of 76 μm. The coarse particles were removed with a volume average particle size of 53.8 μm, a true specific gravity of 3.60 g / cm ³ , a magnetization strength of 191 kAm ² / m ³ , a specific resistance of 5.2 × 10 ⁸ Ω · cm, and an average circularity. Carrier F in which the abundance of particles having a circularity of C of 0.900, standard deviation σ of 0.055, and (average circularity C−2σ) = 0.790 is 6.2% by number was obtained. Most of the obtained carriers had a spherical to elliptical shape, and some irregular particles were present on the fine powder side.

(Carrier Production Example G)
Magnetite powder having a number average particle size of 250 nm and a specific resistance of 5.1 × 10 ⁵ Ω · cm used for carrier A (magnetization strength at 79.6 kA / m 64 Am ² / kg, true specific gravity 5.2 g / cm ³ ) A hematite powder (nonmagnetic, true specific gravity 5.1 g / cm ³ ) having a number average particle size of 260 nm and a specific resistance of 4.9 × 10 ⁷ Ω · cm was used without any treatment.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 37 mass% aqueous solution) 6 parts by mass-Magnetite fine particles 76 parts by mass-Hematite fine particles 8 parts by mass-Calcium fluoride 1 part by mass The above materials and 28 mass% ammonia water 5 masses Part and 10 parts by mass of water were placed in a flask and mixed well. At this time, the amount of dissolved oxygen in the reaction medium was 7.2 g / m ³ . Without introducing nitrogen, the mixture was heated from room temperature at an average rate of temperature increase of 3.0 ° C./min, heated to 85 ° C. with stirring, and allowed to polymerize for 3 hours to be cured. The stirring blade peripheral speed at this time was 1.8 m / sec. Then, after cooling to 30 ° C. and further adding water, the supernatant was removed, and the precipitate was washed with water and then air-dried. Subsequently, this was dried under reduced pressure (5 hPa or less) at a temperature of 60 ° C. to obtain a magnetic carrier core (g) having a volume average particle diameter of 35.6 μm in which a magnetic material was dispersed.

The magnetic carrier core (g) is coated with the same formulation as the carrier A, and has a volume average particle size of 35.9 μm, a true specific gravity of 3.59 g / cm ³ , a magnetization strength of 190 kAm ² / m ³ , and a specific resistance of 3.5. × 10 ⁸ Ω · cm, average circularity C is 0.874, standard deviation σ is 0.076, and (average circularity C−2σ) = 0.722 or less of particles having a circularity of 20.4 A number% carrier G was obtained. Many of the obtained carriers were spherical, but oval and amorphous particles were mixed.

(Carrier Production Example H)
A magnetite powder having a number average particle size of 220 nm is calcined in air at 700 ° C. for 3 hours and magnetite powder having a number average particle size of 220 nm and a specific resistance of 8.5 × 10 ⁷ Ω · cm (magnetization strength at 79.6 kA / m). 58 Am ² / kg, true specific gravity 5.1 g / cm ³ ). Thereafter, 4.5% by mass of a silane coupling agent (3- (2-aminoethylaminopropyl) trimethoxysilane) was added, and the mixture was stirred at 120 ° C. at high speed in the container for surface treatment.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 37% by weight aqueous solution) 6 parts by mass-Treated magnetite 84 parts by weight The above materials, 28 parts by weight ammonia water 5 parts by weight, water 15 parts by weight are placed in a flask and mixed well did. At this time, the amount of dissolved oxygen in the reaction medium was 7.4 g / m ³ . Nitrogen gas was then introduced into the reaction medium. Nitrogen gas was introduced at a flow rate of 1.5 × 10 ⁻² m ³ / h for 20 minutes. At this time, the amount of dissolved oxygen in the reaction medium was 0.92 g / m ³ . Thereafter, the amount of nitrogen introduced was suppressed to 0.3 × 10 ⁻² m ³ / h, heated from room temperature at an average rate of temperature increase of 3.0 ° C./min, heated to 85 ° C. with stirring, and polymerized for 3 hours. Reacted and cured. The stirring blade peripheral speed at this time was 2.8 m / sec. Then, after cooling to 30 ° C. and further adding water, the supernatant was removed, and the precipitate was washed with water and then air-dried. Subsequently, this was dried under reduced pressure (5 hPa or less) at a temperature of 60 ° C. to obtain a spherical magnetic carrier core (h) having a volume average particle diameter of 14.2 μm in a state where the magnetic material was dispersed.

1.0 part by mass of spherical silica particles (number average particle size 300 nm), carbon black (number average particle size 30 nm, DBP oil absorption) with respect to 50 parts by mass of the graft copolymer solution (solid content 33% by mass) used in carrier A (Amount 40 ml / 100 g) 1.5 parts by mass and 100 parts by mass of toluene are mixed well by a homogenizer. Subsequently, 1000 parts by mass of the magnetic carrier core (h) was stirred while continuously applying shear stress, and the above coating solution was gradually added, and the solvent was volatilized at 70 ° C. to perform resin coating on the carrier surface. . The amount of nitrogen introduced is 0.3 × 10 ⁻² m ³ / h, heat treated at 100 ° C. for 2 hours, cooled, crushed, coarse particles are removed with a sieve having an aperture of 76 μm, and volume averaged particles are obtained. Diameter 14.4 μm, true specific gravity 3.58 g / cm ³ , magnetization strength 196 kAm ² / m ³ , specific resistance 2.8 × 10 ⁹ Ω · cm, average circularity C 0.865, standard deviation σ 0 .103, (average circularity C−2σ) = 0.659 or less, the carrier H having a circularity of 7.9% by number was obtained. Many of them have an elliptical shape, and there are slender elliptical shapes, or irregular particles on the fine powder side.

(Carrier Production Example I)
They were weighed so that Fe ₂ O ₃ = 52 mol%, CuO = 24 mol%, and ZnO = 24 mol% in terms of molar ratio, and pulverized and mixed for 10 hours using a ball mill. This was calcined at 900 ° C. for 2 hours, then pulverized with a ball mill, and further granulated with a spray dryer using polyvinyl alcohol as a binder resin. This was sintered at 1080 ° C. for 10 hours in a nitrogen atmosphere, pulverized, and further subjected to air classification to obtain a Cu—Zn ferrite carrier core (i) in which many amorphous particles having a volume average particle diameter of 32.1 μm were present.

For 20 parts by mass of graft copolymer solution (solid content 33% by mass) used in carrier A, 0.5 parts by mass of spherical silica particles (number average particle size 300 nm), carbon black (number average particle size 30 nm, DBP oil absorption) (Amount 40 ml / 100 g) 1.0 part by mass and 100 parts by mass of toluene are mixed well by a homogenizer. Next, while stirring 1000 parts by mass of Cu-Zn ferrite carrier core (i) while continuously applying shear stress, the above coating solution is gradually added, and the solvent is volatilized at 70 ° C. Went. The amount of nitrogen introduced is 0.3 × 10 ⁻² m ³ / h, heat treated at 100 ° C. for 2 hours, cooled, crushed, coarse particles are removed with a sieve having an aperture of 76 μm, and volume averaged particles are obtained. Diameter 32.3 μm, True specific gravity 5.03 g / cm ³ , Magnetization strength 301 kAm ² / m ³ , Specific resistance 2.2 × 10 ⁸ Ω · cm, Average circularity C 0.848, Standard deviation σ 0 .112, (average circularity C−2σ) = 0.624 or less, Carrier I having a presence ratio of particles having a circularity of 10.6% by number was obtained. Although some of the obtained carriers were spherical, many of them were amorphous, and a plurality of agglomerated particles were present, or many irregular particles were present on the fine powder side.

(Toner Production Example 1)
As a vinyl copolymer material, 10 parts by mass of styrene, 5 parts by mass of 2-ethylhexyl acrylate, 2 parts by mass of fumaric acid, and 5 parts by mass of dimer of α-methyl styrene are added 5 parts by mass of dicumyl peroxide. Put in. Moreover, as a material of the polyester unit, 25 parts by mass of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis (4- Hydroxyphenyl) propane (15 parts by weight), terephthalic acid (9 parts by weight), trimellitic anhydride (5 parts by weight), fumaric acid (24 parts by weight) and 2-ethylhexanoic acid tin (0.2 parts by weight) in a glass 4-liter four-necked flask The thermometer, stir bar, condenser and nitrogen inlet tube were attached to a four-necked flask, and this four-necked flask was placed in a mantle heater. Next, after the inside of the four-necked flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and while stirring at a temperature of 130 ° C., the monomer and the polymerization of the vinyl copolymer from the previous dropping funnel The initiator was added dropwise over about 4 hours. Next, the temperature was raised to 200 ° C. and reacted for about 4 hours to obtain a resin having a weight average molecular weight of 79,000 and a number average molecular weight of 3900.
-100 parts by mass of the above resin-Purified normal paraffin (maximum endothermic peak temperature 80 ° C, Mw800, Mn600) 5 parts by mass-3,5-di-t-butylsalicylic acid aluminum compound 0.5 parts by mass I. Pigment Blue 15: 3 5 parts by mass After mixing the material of the above formulation with a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.), a twin-screw kneader (PCM-30) set at a temperature of 130 ° C. Kneaded with a mold, manufactured by Ikekai Tekko Co., Ltd. The obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized material. The obtained coarsely pulverized toner was finely pulverized using a collision-type airflow pulverizer using high-pressure gas to obtain a finely pulverized product. Further, the obtained finely pulverized product is treated with a processing apparatus as shown in FIGS. 2 and 3 and the fine powder is removed at the classification rotor rotational speed 120 s ⁻¹ while the dispersed rotor rotational speed 100 s ⁻¹ (rotational peripheral speed is reduced). The surface treatment was performed at 130 m / sec) for 45 seconds (after the finely pulverized material had been charged from the raw material supply port 33, the treatment was performed for 45 seconds, and then the discharge valve 38 was opened to be taken out as a treated product). At that time, 40 square disks were installed on the upper side of the dispersion rotor 6, the distance between the guide ring 39 and the upper square disk on the dispersion rotor 36 was 30 mm, and the distance between the dispersion rotor 36 and the liner 34 was 3 mm. The blower air volume was 14 m ³ / min, the temperature of the refrigerant passed through the jacket and the cold air temperature T1 were −20 ° C.

  As a result of repeated operation in this state for 20 minutes, the temperature T2 behind the classification rotor 31 was stable at 26 ° C., and cyan particles having a weight average particle diameter of 5.7 μm and an average circularity of T0.943 were obtained.

  1.0 part by mass of silica particles having a maximum peak particle size of 110 nm based on the number distribution, 100 parts by mass of cyan particles obtained, and a titanium oxide particle having a maximum peak particle size of 50 nm based on the number distribution and a hydrophobization degree of 70% 0.9 part by mass, 0.5 part by mass of silicone oil-treated silica particles having a maximum peak particle size of 20 nm based on the number distribution and a hydrophobization degree of 98%, are added to a Henschel mixer (FM-75 type, Mitsui Miike Chemical Industries). And cyan toner 1 having a weight average particle diameter of 5.8 μm and an average circularity of T0.943 was obtained.

(Toner Production Example 2)
A finely pulverized product was obtained in the same manner as toner 1 in the formulation used for toner 1. Furthermore, surface modification was performed with a hybridizer (manufactured by Nara Machinery Co., Ltd.) at a rotation speed of 125 s ⁻¹ to obtain cyan particles having a weight average particle diameter of 5.2 μm and an average circularity of T0.934. Since there are more fine powders than Toner 1, classification was performed by a multi-division classifier using the Coanda effect to obtain cyan particles having a weight average particle size of 5.6 μm and an average circularity of T0.936.

  External addition similar to that of Toner 1 was performed to obtain Cyan Toner 2 having a weight average particle size of 5.6 μm and an average circularity of T0.935.

(Toner Production Example 3)
A finely pulverized product was obtained in the same manner as toner 1 in the formulation used for toner 1. The obtained finely pulverized toner was classified by a multi-division classifier using the Coanda effect to obtain cyan particles having a weight average particle size of 5.5 μm and an average circularity of T0.915.

  External addition similar to that of Toner 1 was performed to obtain Cyan Toner 3 having a weight average particle size of 5.6 μm and an average circularity of T0.915.

(Toner Production Example 4)
-Styrene 86 parts by mass-n-butyl acrylate 14 parts by mass-Acrylic acid 3 parts by mass-Dodecanethiol 6 parts by mass-Carbon tetrabromide 1 part by mass Surfactant (Sanyo Kasei Co., Ltd .: Nonipol 400) 1.5 parts by mass and anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) 2.5 parts by mass ion-exchanged water 140 parts by mass After being dispersed in a flask, dispersed in a flask, emulsified, and slowly mixed for 10 minutes, 10 parts by mass of ion-exchanged water in which 1 part by mass of ammonium persulfate was dissolved was added, and after nitrogen substitution, While stirring the inside of the flask, the contents were heated in an oil bath until the content reached 70 ° C., and emulsion polymerization was continued for 5 hours. A resin particle dispersion 1 in which resin particles having a number average particle diameter of 0.14 μm were dispersed was prepared.

Also,
-Styrene 75 parts by mass-n-butyl acrylate 25 parts by mass-Acrylic acid 2 parts by mass Mixing and dissolving the above-mentioned ingredients, a nonionic surfactant (Sanyo Kasei Co., Ltd .: Nonipol 400) 1.5 parts by mass and 3.5 parts by mass of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) dissolved in 150 parts by mass of ion-exchanged water are dispersed and emulsified in a flask. While slowly mixing for 10 minutes, 10 parts by mass of ion-exchanged water having 0.8 parts by mass of ammonium persulfate dissolved therein was added thereto, and after nitrogen substitution, the contents were kept at 70 ° C. while stirring the flask. The mixture was heated in an oil bath until emulsion polymerization was continued for 5 hours to prepare a resin particle dispersion 2 in which resin particles having a number average particle size of 0.12 μm were dispersed.

further,
・ Purified normal paraffin (Mw800, Mn600, maximum endothermic peak temperature 80 ° C.) 50 parts by mass • Anionic surfactant 5 parts by mass (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
-Ion-exchanged water 200 parts by weight The above-mentioned prescription material was heated to 97 ° C and dispersed using a homogenizer (manufactured by IKA: Ultra Turrax T50), then dispersed with a pressure discharge type homogenizer, and the number average particle A release agent dispersion was prepared by dispersing a release agent having a diameter of 0.41 μm.

further,
・ C. I. Pigment Blue 15: 3 12 parts by mass, anionic surfactant 2.5 parts by mass (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
-Ion-exchanged water 78 parts by mass The above-mentioned ingredients were mixed and dispersed using a sand grinder mill to prepare a colorant dispersion in which a colorant having a number average particle size of 0.2 μm was dispersed. .

further,
-150 parts by mass of the resin particle dispersion 1-210 parts by mass of the resin particle dispersion 2-40 parts by mass of the release agent dispersion-70 parts by mass of the colorant dispersion are mixed with a stirrer, a cooling tube, and a thermometer. Was put into a 1 liter separable flask equipped with, and stirred. The mixture was adjusted to pH = 5.3 using 1 mol / liter-potassium hydroxide.

  150 parts by mass of a 10% aqueous sodium chloride solution as a flocculant was added dropwise to this mixed solution, and the mixture was heated to 70 ° C. while stirring the inside of the flask in a heating oil bath. At this temperature, 3 parts by mass of the resin particle dispersion 2 was added. After holding at 70 ° C. for 1 hour, 3 parts by mass of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) was added here, and then the stainless steel flask was sealed and stirred using a magnetic seal. The mixture was heated to 90 ° C. while maintaining for 3 hours. Then, after cooling, the reaction product was filtered, sufficiently washed with ion-exchanged water, and dried to obtain cyan particles having a weight average particle size of 4.7 μm and an average circularity of 0.964.

  To 100 parts by mass of the obtained cyan particles, 1.5 parts by mass of silica particles having a maximum peak particle size of 90 nm based on the number distribution, titanium oxide particles having a maximum peak particle size of 40 nm based on the number distribution and a hydrophobization degree of 70% 0.9 parts by mass and mixing with a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.) to obtain cyan toner 4 having a weight average particle diameter of 4.8 μm and an average circularity of 0.964. Obtained.

(Toner Production Example 5)
To 710 parts by mass of ion-exchanged water, 450 parts by mass of 0.12 mol / liter-Na ₃ PO ₄ aqueous solution was added and heated to 60 ° C., and then using a TK homomixer (made by Tokushu Kika Kogyo Co., Ltd.) Stir at 11,000 rpm. To this, 70 parts by mass of a 1.2 mol / liter-CaCl ₂ aqueous solution was gradually added to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

on the other hand,
Styrene 62 parts by mass n-butyl acrylate 38 parts by mass Ester wax (main component: CH ₃ (CH ₂ ) ₂₀ COO (CH ₂ ) ₂₁ CH ₃ , Mw 650, Mn 500, maximum endothermic peak temperature 72 ° C.) 20 parts by mass -Aluminum 3,5-di-t-butylsalicylate compound 1 part by mass-Saturated polyester (terephthalic acid-propylene oxide modified bisphenol A; acid value 15, peak molecular weight 6000) 10 parts by mass I. Pigment Blue 15: 3 12 parts by mass The above material was heated to 60 ° C., and uniformly dissolved and dispersed at 10,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.). In this, 8 parts of polymerization initiators 2,2′-azobis (2,4-dimethylvaleronitrile) were dissolved to prepare a polymerizable monomer composition.

The polymerizable monomer composition was put into an aqueous medium and stirred at 11,000 rpm for 10 minutes with a TK homomixer in a nitrogen atmosphere at 60 ° C. to granulate the polymerizable monomer composition. . Then, while stirring with a paddle stirring blade, the temperature was raised to 80 ° C. and reacted for 10 hours. After completion of the polymerization reaction, the residual monomer is distilled off under reduced pressure, and after cooling, hydrochloric acid is added to dissolve Ca ₃ (PO ₄ ) _{2 and the} like, followed by filtration, washing with water, and drying to obtain a weight average particle size of 7. Cyan particles having a size of 1 μm and an average circularity of 0.985 were obtained.

  To 100 parts by mass of the obtained cyan particles, 0.5% by mass of 65% titanium oxide particles having a maximum peak particle size of 40 nm based on the number distribution and a maximum peak particle size of 30 nm based on the number distribution and having a hydrophobicity of 95 % Silica particles are added in an amount of 0.8 parts by mass, mixed with a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.), and have a weight average particle size of 7.2 μm and an average circularity of 0.985. Of cyan toner 5 was obtained.

(Toner Production Examples 6 to 8)
The coloring agents used in Toner Production Example 1 were 8 parts by weight of Pigment Yellow 74 (Yellow Toner 6), 8 parts by weight of Pigment Red 122 (Magenta Toner 7), and 6 of Carbon Black Printex 60 (manufactured by Degussa). A toner was prepared in the same manner as in Toner Production Example 1 except that the amount was changed to part by mass (black toner 8). Yellow toner 6 having a weight average particle size of 5.8 μm, average circularity T0.949, magenta toner 7 (magenta toner) having a weight average particle size of 5.7 μm and an average circularity T0.943, a weight average particle size of 5.9 μm, Toner black 8 (black toner) having an average circularity of T0.946 was obtained.

(Photoconductor Production Example 1)
An aluminum cylinder (JIS A3003 aluminum alloy) subjected to honing treatment with a length of 340 mm and a diameter of 84 mm is used as a support, and a 5% by mass methanol solution of polyamide resin (trade name: Amilan CM8000, manufactured by Toray) is applied thereon by a dipping method. Then, an undercoat layer having a layer thickness of 0.5 μm was formed.

  Next, 3 parts by mass of a crystal of hydroxygallium phthalocyanine having a diffraction peak 2θ ± 0.2 having a strongest peak at 28.1 ° in X-ray diffraction of CuKα as a charge generation material and 2 parts by mass of polyvinyl butyral are combined with 100 parts by mass of cyclohexanone. The mixture is dispersed in a sand mill using glass beads having a diameter of 1 mm for 1 hour, and 100 parts by mass of methyl ethyl ketone is added thereto to dilute to prepare a coating for a charge generation layer. The charge generation layer is formed on the undercoat layer. The coating material was dip coated and dried at 90 ° C. for 10 minutes to form a charge generation layer having a layer thickness of 0.17 μm.

  Subsequently, 7 parts by mass of the charge transport material compound represented by the following formula

And 10 parts by mass of polycarbonate resin (Iupilon Z400, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) were dissolved in 105 parts by mass of monochlorobenzene and 35 parts by mass of dichloromethane. This solution was dip-coated on the charge generation layer and dried with hot air at 110 ° C. for 1 hour to form a first charge transport layer having a layer thickness of 12.0 μm. Further, a second charge transport layer was formed as a surface layer on the first charge transport layer.

  As the second charge transport layer, the following polymerizable functional group (2)

A surface layer containing a compound obtained by polymerizing a hole transporting compound having the following formula (Chemical Formula 2) by electron beam irradiation was applied and cured.

Dissolve 45 parts by mass of this hole transporting compound in 55 parts by mass of n-propyl alcohol, add 5 parts by mass of tetrafluoroethylene fine particles, and disperse with a high-pressure disperser (Microfluidizer, manufactured by Microfluidics). A second charge transport layer coating was prepared. After applying this paint on the four-layer photoconductor, an electron beam is irradiated under conditions of an acceleration voltage of 150 kV and a dose of 40 kGy to form a second charge transport layer having a layer thickness of 3.0 μm, and a total layer thickness of 15.67 μm. Photoconductor 1 was obtained. The photoreceptor 1 was processed so that it could be mounted on a copying machine iRC6800 manufactured by Canon Inc. The HU at this time was 1.9 × 10 ⁸ N / m ² , and the elastic deformation rate was 54%.

(Photoconductor Production Example 2)
The photoconductor 2 having a total layer thickness of 15.67 μm was obtained by irradiating with an electron beam under the conditions where the acceleration voltage for preparing the second charge transport layer of the photoconductor 1 was 150 kV and the dose was reduced to 20 kGy. At this time, the HU was 1.6 × 10 ⁸ N / m ² and the elastic deformation rate was 51%.

(Photoconductor Production Example 3)
Further, in place of the hole transporting compound used in forming the second charge transport layer of the photoreceptor 1, polymerizable functional groups (2), (4)

The following (Chemical Formula 3) having the following structure is used to form a second charge transport layer, and the thickness is changed to 18.0 μm for the first charge transport layer and 3.0 μm for the second charge transport layer. The photoreceptor 3 having a total layer thickness of 24.67 μm was obtained.

At this time, the HU of the photosensitive member 3 was 1.2 × 10 ⁶ N / m ² and the elastic deformation rate was 48%.

(Photoconductor Production Example 4)
The thickness of the hole transport layer of the photoreceptor 3 was set to 30.0 μm, and the photoreceptor 4 having a total layer thickness of 30.67 μm was obtained without forming the second charge transport layer. The HU at this time was 5.6 × 10 ⁶ N / m ² and the elastic deformation rate was 36%.

<Example 1>
8 parts by mass of cyan toner 1 is added to 92 parts by mass of carrier A, and mixed for 2 minutes by a tumbler mixer to obtain a developer.

  The image processing and exposure apparatus of the Canon color compound machine iRC6800 was modified so that a latent image can be formed by image exposure. In addition, the developer carrying member of the developing container was modified so that the rotation direction of the developer carrying member was rotated in the same direction as the photosensitive member (from the top to the bottom) in the developing region. Further, a blade made of polyurethane resin (hardness (Hs) is measured with a JIS-A spring hardness meter: hardness 78 degrees, friction coefficient 0.5) is used as a cleaning member so as to contact the photoconductor with a counter. And modified to slide in the longitudinal direction. Using the photoreceptor 1, the developer was put in a developing device at a cyan position to form an image in a single color. Image evaluation (100 sheets) was performed under high temperature and high humidity H / H (30 ° C, 80% RH), and then the machine was transferred to room temperature and low humidity N / L (23.5 ° C, 10% RH) for 24 hours. After standing, image output evaluation was performed at the initial stage (at the time of 100 sheets) and after durability. For the image sample in durability, the image output evaluation is performed after outputting 50,000 sheets using a 1% duty image. However, when an image defect (streak, fog, etc.) appeared during the endurance, the endurance was stopped and the image was evaluated there.

The developing condition was that the photosensitive member of the present invention was used, the laser spot diameter was 600 dpi, the developing sleeve and the photosensitive member were rotated in the forward direction in the developing region, and the developing sleeve peripheral speed was 1.5 times that of the photosensitive member. Further, an AC bias having a Vp-p (peak-to-peak voltage) of 1.8 kV and a frequency of 2.0 kHz was applied to the developing sleeve. Then, it is applied while varying the DC bias application voltage V _DC so that the density of the solid image is about 1.60, and the contrast potential (V ₁ (bright part potential) −V _DC (DC bias application voltage) is applied. ) Was adjusted. At that time, when the contrast potential was set to 300 V at the maximum and a higher contrast potential was required to output an image density of 1.60, image formation was performed at 300 V. Then, the following evaluation was performed using the image thus obtained. The items and evaluation criteria for image output evaluation at the initial stage and after the endurance are shown below.

(1) Image density and contrast width (initial and after endurance)
The image density of the fixed image when the solid image is fixed at 170 ° C. is measured using an X-Rite 500 series (manufactured by X-Rite 504 X-Rite, Inc.).

  As for the contrast width, the contrast potential when the solid image becomes about 1.60 is read from the machine.

(2) Dot reproducibility (initial and after durability)
A halftone image (30H image) was formed, this image was visually observed, and dot reproducibility of the image was evaluated based on the following criteria. The 30H image is a halftone image of the 49th gradation counted from the solid white image when the solid white to the solid black are divided into 256 gradations.
A: Smooth and smooth.
B: I don't feel a lot of rustling.
C: There is a slight feeling of roughness.
D: There is a clear feeling of roughness.
E: There is a very rough feeling.

(3) Fog (initial and after durability)
The average reflectance Dr (%) of plain paper before image printing is measured with a reflectometer (“REFECTOMETER MODEL TC-6DS” manufactured by Tokyo Denshoku Co., Ltd.). On the other hand, a solid white image is drawn on plain paper in a state where Vback is 150 V, and then the reflectance Ds (%) of the solid white image is measured. The fog (%) is calculated from the following formula.
Fog (%) = Dr (%) − Ds (%)
A: Less than 0.4% B: Less than 0.4-1.0% C: Less than 1.0-2.5% D: Less than 2.5-5.0% E: 5.0% or more

(4) Carrier adhesion (initial)
A solid white image is printed on plain paper with Vback 150 V, and the part on the photosensitive drum between the developing unit and the cleaner unit is sampled by attaching a transparent adhesive tape to the photosensitive drum in 1 cm × 1 cm. The number of magnetic carrier particles adhering to 1 is counted, and the number of adhering carriers per 1 cm ² is calculated.
A: Less than 10 pieces / cm ² B: 10 pieces to less than 20 pieces / cm ² C: 20 pieces to less than 50 pieces / cm ² D: 50 pieces to less than 100 pieces / cm ² E: 100 pieces / cm ² or more

(5) Drum life level (after endurance)
50,000 photoconductors after endurance at low temperature and normal humidity (23.5 ° C., 50% RH) are evaluated visually. Further, the occurrence of streaks (the circumferential direction of the photoreceptor) of the halftone image is visually evaluated. If an image defect occurs during the endurance, the end of endurance is completed and a predetermined evaluation is performed. In that case, the evaluation is performed with the number of sheets at the end of the endurance.
A: No damage occurred.
B: Slightly observed scratches when observed closely.
C: Scratches are seen but the image is not affected.
D: Scratches can be clearly confirmed visually, and the image is slightly affected.
E: Scratches can be confirmed visually and image defects are remarkable. Or, an image defect occurs before 50,000 sheets.

(6) Measurement of triboelectric charge amount of toner The following operation is performed in a room controlled at 23 ° C. and 50% RH.

  The developer is collected in a container under each environment and sealed, and then mixed for 120 seconds with a tumbler mixer. Further, the triboelectric charge amount of the toner at the time of durability is used without remixing by sampling the developer from above the developing sleeve via a plastic bag or the like with a magnet.

  And E-SPART Analyzer MODEL EST-III ver. Using 9.03 (manufactured by Hosokawa Micron Corporation), the triboelectric charge amount of the toner is measured as follows.

The above-described developer is held in a two-component feeder (developer holding stand having a rotating disk with a built-in magnet) attached to E-SPART Analyzer (manufactured by Hosokawa Micron). Next, nitrogen gas is sprayed from the air nozzle to the developer held magnetically in the two-component feeder to blow off only the toner, and only the toner is sucked into the E-SPART Analyzer measuring section through the sample introduction tube under the two-component feeder. To do. The toner sucked into the measurement unit is measured for a charge amount q / d (femt−C / μm) corresponding to the particle diameter d (μm). Based on this data, the average triboelectric charge quantity q / m of all particle diameters is obtained by the attached software. In addition, the measurement conditions of E-SPART Analyzer in this embodiment shall be as follows.
Nitrogen gas blow pressure: 20 kPa
Nitrogen gas blow time: 1 second Nitrogen gas blow interval: 4 seconds Applied voltage: 100V
Count number: 3000

  In this example, the contrast at H / H was sufficient, and the dot reproducibility in the halftone image was very good. Also, fog and carrier adhesion were sufficient, and the result of outputting 50,000 sheets at low temperature and normal humidity was sufficient in image density and contrast, and toner separation was very good. Furthermore, good results were obtained with respect to dot reproducibility and fog. There was no carrier adhesion, and there was no drum scratch caused by the carrier.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 2>
8 parts by mass of cyan toner 1 is added to 12 parts by mass of carrier B, and mixed for 2 minutes by a tumbler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, both H / H and N / L had sufficient image density and contrast, and the dot reproducibility was very excellent, but some carrier adhesion occurred. Durability was slightly deteriorated in durability, but no drum scratches occurred.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 3>
To 94 parts by mass of carrier C, 6 parts by mass of toner 1 is added and mixed for 2 minutes by a turbuler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, the contrast was slightly lost at H / H, and the dot reproducibility was slightly inferior. Further, carrier adhesion did not occur, but some drum scratches occurred after durability. In addition, fogging, which is considered to be toner deterioration, also decreased.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 4>
12 parts by mass of toner 1 is added to 88 parts by mass of carrier D, and mixed for 2 minutes by a tumbler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, the image density, contrast, and dot reproducibility were very good, but some durability and some carrier adhesion occurred. There were a few scratches on the drum that may have been attributed to it.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 5>
To 94 parts by mass of carrier E, 6 parts by mass of toner 1 is added and mixed for 2 minutes by a tumbler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, contrast was sufficient at H / H and the image density was good, but at N / L, the toner was slightly separated and the developability was slightly lowered. It was thought that fogging, which was considered to be a deterioration of the toner in durability, occurred, and on the other hand, carrier adhesion appeared and drum scratches occurred, but the image was not affected.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 6>
To 94 parts by mass of carrier F, 6 parts by mass of toner 1 is added and mixed for 2 minutes by a turbuler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, contrast was sufficient at H / H and the image density was good, but at N / L, the toner was slightly separated and the developability was slightly lowered. A fogging that appears to have deteriorated the toner in durability and the contrast was not sufficient, but the image was not affected. Further, it was considered that carrier adhesion appeared and drum scratches were generated, but the image was not affected.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Comparative Example 1>
To 92 parts by mass of carrier G, 8 parts by mass of toner 2 is added, and mixed for 2 minutes by a tumbler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, at N / L, the contrast of the image density considered to be caused by poor toner separation could not be obtained. In addition, the carrier adhesion was slightly increased, and fine scratches entered during durability, resulting in poor dot reproducibility.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Comparative example 2>
To 84 parts by mass of carrier H, 16 parts by mass of toner 2 is added, and mixed for 2 minutes by a tumbler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, the image density and contrast were sufficient, and the dot reproducibility was very excellent. However, carrier adhesion was very large, and a minute scratch (photosensitive material matted) occurred in the first half of the durability, but the matting did not spread and the durability of 50,000 sheets could be achieved. However, after the endurance, it became inferior in dot reproducibility due to fine scratches.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Comparative Example 3>
To 94 parts by mass of carrier I, 6 parts by mass of toner 2 is added and mixed for 2 minutes by a turbuler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, the image density was sufficient at H / H, but the contrast potential could not be obtained because the charge amount was low, resulting in unevenness in the stitches and poor dot reproducibility. At N / L, the amount of carrier adhesion was slightly increased, and fine scratches were formed on the surface of the photoreceptor, and the range gradually expanded as the durability was increased. Therefore, the durability was stopped after 33,000 sheets, and as a result of performing image evaluation at that time, the fog was also deteriorated.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 7>
To 94 parts by mass of carrier E, 6 parts by mass of toner 2 is added and mixed for 2 minutes by a tumbler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, since the tribo was low at H / H, the contrast could not be obtained and the dot reproducibility was slightly inferior, but there was no practical problem. In terms of durability, it was a practical level although the photoconductor had fine scratches.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 8>
To 94 parts by mass of carrier E, 6 parts by mass of toner 3 is added and mixed for 2 minutes by a turbuler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, although the tribo was slightly low in both H / H and N / L environments, the contrast could not be obtained, but it was at a level that could be applied practically. Although the fog slightly deteriorated in durability and the fine scratch range of the photoconductor was slightly expanded, it was at a level of no practical problem.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 9>
To 94 parts by mass of carrier F, 6 parts by mass of toner 4 is added and mixed for 2 minutes by a tumbler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, in H / H, both image density and contrast were sufficient, and in N / L, dot reproducibility, fog and carrier adhesion were good, but toner tribo was high, toner separation was slightly inferior and density was not. However, there was no problem in practical use. In terms of durability, although the fog was slightly deteriorated, a good image was formed.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 10>
Add 90 parts by mass of carrier F instead of toner 5 and add 10 parts by mass, and mix for 2 minutes with a turbula key to obtain a developer.

  A test was conducted in the same manner as in Example 1 using this developer. As a result, although the tribo was slightly low at H / H, both image density and contrast were sufficient, and at N / L, the dot reproduction was slightly inferior to that of Example 1. Further, although the dot reproduction and fog were slightly inferior in durability, the image formation was almost satisfactory.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 11>
To 92 parts by mass of carrier B, 8 parts by mass of toner 1 is added and mixed for 2 minutes by a turbuler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 except that the photoconductor 1 used in Example 1 was changed to the photoconductor 2 and this developer was used. As a result, in H / H, both the image density and the contrast were sufficient, and the dot reproducibility was very good. However, although fog and carrier adhesion were slightly inferior, there was no problem in practical use. After the endurance, the fog slightly deteriorated, and slight scratches on the surface of the photoconductor, which are thought to be due to carrier adhesion, were slightly observed.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Example 12>
To 92 parts by mass of carrier B, 8 parts by mass of toner 1 is added and mixed for 2 minutes by a turbuler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 except that the photoconductor 1 used in Example 1 was changed to the photoconductor 3 and this developer was used. As a result, the tribo is sufficient in H / H, but the contrast is reduced because the film thickness of the photosensitive member is increased. Also, the dot reproducibility was slightly inferior to that of Example 1. After the endurance of 50,000 sheets, fine scratches were observed on the surface of the photoreceptor.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Comparative example 4>
To 92 parts by mass of carrier B, 8 parts by mass of toner 2 is added and mixed for 2 minutes by a turbuler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 by using the developer in place of the photoreceptor 1 used in Example 1 instead of the photoreceptor 4. As a result, at H / H, the contrast potential became extremely small, and an image with inferior gradation was obtained. Further, the dot reproducibility is also inferior, and these are considered to be caused by the thickness of the charge transport layer. Further, in terms of durability, the occurrence of fine scratches on the surface of the photoreceptor became prominent, and streaks were observed on the image with 25,000 sheets. When image evaluation was performed at this point, the dot reproducibility was slightly inferior.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Comparative Example 5>
The carrier B of Comparative Example 4 is changed to the carrier I, and 8 parts by mass of the toner 2 is added to 92 parts by mass of the carrier I, and mixed for 2 minutes by a turbuler mixer to obtain a developer.

  A test was conducted in the same manner as in Example 1 using the photoreceptor 4 and this developer. As a result, at H / H, the contrast potential became extremely small, and an image with inferior gradation was obtained. In addition, the dot reproducibility was inferior and unevenness in the stitches occurred. These are considered to be caused by the thickness of the charge transport layer, the specific gravity of carriers, and the magnetic force. Further, in the endurance, fine scratches on the surface of the photoreceptor became remarkable, and streaks were also observed on the image with 19,000 sheets. When the image was evaluated at this point, the dot reproducibility was very poor and the fog was also deteriorated. These are considered to be due to toner deterioration and spent to the carrier.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

<Examples 13 to 15>
The toner used in Example 1 was changed to toner 6 (yellow toner), toner 7 (magenta toner), and toner 8 (black toner), respectively, and 92 parts by mass of carrier A was added to 8 parts by mass of each toner. The mixture was mixed for 2 minutes using a tumbler mixer to prepare a yellow developer, a magenta developer, and a black developer.

  Using these developers, the photosensitive member 1 was used and examined under the same conditions as in Example 1.

  As a result, both image density and dot reproducibility were excellent, and fog and carrier adhesion were also good. In addition, the contrast was sufficiently high and good image formation was possible. In terms of durability, good results were obtained as in Example 1.

  Table 1 shows the physical properties of the carrier, Table 2 shows the physical properties of the toner, and Table 3 shows the test results of the developer.

It is a schematic sectional drawing showing an example of the image forming method of this invention. FIG. 3 is a schematic cross-sectional view illustrating a configuration of an example of a surface modification device used in a surface modification step when manufacturing the toner of the present invention. It is the schematic which shows an example of the top view of the dispersion | distribution rotor shown in FIG. It is a schematic sectional drawing of the apparatus which measures the specific resistance of the carrier of this invention, a magnetic body, and a nonmagnetic inorganic compound. It is an example of the graph of a measurement result about the particle size distribution and circularity of the carrier of this invention. The left axis shows the frequency of particle size based on the number as a bar graph. The degree of circularity is shown as a dot on the right axis. It is the schematic of the output chart which measures the surface elastic modulus of the photoconductor of this invention.

Claims (12)

An electrostatic latent image is formed on a photosensitive member having at least a charge generation layer and a charge transport layer on a conductive support, and the electrostatic latent image is developed using a two-component developer containing a toner and a carrier. In the image forming method,
The photoreceptor has a surface elastic deformation ratio of 46 to 65%, a universal hardness value (HU) of 1.5 × 10 ^{8 to} 2.3 × 10 ⁸ (N / m ² ), and the charge transport layer. Has a layer thickness of 8.0 to 20.0 μm,
The toner has a weight average particle diameter (D4) of 3.0 to 10.0 μm,
The carrier has a volume average particle diameter (Dv) of 15.0 to 60.0 μm, an average circularity C of 0.830 to 0.950, and a particle having a circularity of (average circularity C-2σ) or less. An image forming method, wherein (σ is a standard deviation of carrier circularity) is 20% by number or less.   The image forming method according to claim 1, wherein the carrier has a carrier core surface coated with a resin, and the resin contains at least a silicone resin or a fluorine resin. The carrier is a magnetic material-dispersed resin carrier having a magnetic material and a binder resin, the true specific gravity of the carrier is 3.0 to 4.0 g / cm ³ , and the magnetization per carrier volume at 79.6 kA / m. ^3. The image forming method according to claim 1, wherein the strength of the image is 80 to 250 kAm ² / m ³ (emu / cm ³ ).   4. The image formation according to claim 1, wherein the toner has a weight average particle diameter of 4.0 to 8.0 μm and an average circularity of 0.920 to 1.000. 5. Method.   5. The image forming method according to claim 1, wherein the charge transport layer has a thickness of 8.0 to 16.0 [mu] m. The charge transport layer is divided into a first charge transport layer and a second charge transport layer;
The first charge transport layer is a layer in which a charge transport material is dispersed in a binder resin.
The second charge transport layer is a layer forming a surface layer, and is made of a curable resin obtained by polymerizing and curing a compound having a polymerizable functional group represented by the following structural formula (1). The image forming method according to claim 1, wherein:

[E is a hydrogen atom, a halogen atom, an alkyl group which may have a substituent and an aryl group which may have a substituent, a cyano group, a nitro group, an alkoxy group, —COOR ₁ (R ₁ is a hydrogen atom, A halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent and an aryl group which may have a substituent, -CONR ₂ R ₃ (where R ₂ and R ₃ are hydrogen) An atom, a halogen atom, an alkyl group that may have a substituent, an aralkyl group that may have a substituent, and an aryl group that may have a substituent, which may be the same or different W is a divalent arylene group which may have a substituent or a divalent alkylene group which may have a substituent, -COO-, -C-, -O-, -OO- _{, -S -, - CONR 4 -} (R 4 is a hydrogen atom, c A rogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent or an aryl group which may have a substituent, and f represents 0 or 1. ] An image forming apparatus comprising a photoreceptor having at least a charge generation layer and a charge transport layer on a conductive support, and a two-component developer containing a toner and a carrier,
The photoreceptor has a surface elastic deformation ratio of 46 to 65%, a universal hardness value (HU) of 1.5 × 10 ^{8 to} 2.3 × 10 ⁸ (N / m ² ), and the charge transport layer. Has a layer thickness of 8.0 to 20.0 μm,
The toner has a weight average particle diameter (D4) of 3.0 to 10.0 μm,
The carrier has a volume average particle diameter (Dv) of 15.0 to 60.0 μm, an average circularity C of 0.830 to 0.950, and a particle having a circularity of (average circularity C-2σ) or less. An image forming apparatus, wherein (σ is a standard deviation of carrier circularity) is 20% by number or less.   The image forming apparatus according to claim 7, wherein the carrier has a carrier core surface coated with a resin, and the resin contains at least one kind of a silicone resin and a fluorine resin. The carrier is a magnetic material-dispersed resin carrier having a magnetic material and a binder resin, the true specific gravity of the carrier is 3.0 to 4.0 g / cm ³ , and the magnetization per carrier volume at 79.6 kA / m. The image forming apparatus according to claim 7, wherein the strength of the image forming apparatus is 80 to 250 kAm ² / m ³ (emu / cm ³ ).   10. The image formation according to claim 7, wherein the toner has a weight average particle diameter of 4.0 to 8.0 μm and an average circularity of 0.920 to 1.000. apparatus.   11. The image forming apparatus according to claim 7, wherein the charge transport layer has a thickness of 8.0 to 16.0 [mu] m. The charge transport layer is divided into a first charge transport layer and a second charge transport layer;
The first charge transport layer is a layer in which a charge transport material is dispersed in a binder resin.
The second charge transport layer is a layer forming a surface layer, and is made of a curable resin obtained by polymerizing and curing a compound having a polymerizable functional group represented by the following structural formula (1). The image forming apparatus according to claim 7, wherein the image forming apparatus is an image forming apparatus.

[E is a hydrogen atom, a halogen atom, an alkyl group which may have a substituent and an aryl group which may have a substituent, a cyano group, a nitro group, an alkoxy group, —COOR ₁ (R ₁ is a hydrogen atom, A halogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent and an aryl group which may have a substituent, -CONR ₂ R ₃ (where R ₂ and R ₃ are hydrogen) An atom, a halogen atom, an alkyl group that may have a substituent, an aralkyl group that may have a substituent, and an aryl group that may have a substituent, which may be the same or different W is a divalent arylene group which may have a substituent or a divalent alkylene group which may have a substituent, -COO-, -C-, -O-, -OO- _{, -S -, - CONR 4 -} (R 4 is a hydrogen atom, c A rogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent or an aryl group which may have a substituent, and f represents 0 or 1. ]

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