JP5565504B2 - Electrophotographic photosensitive member, electrophotographic photosensitive member cartridge, and image forming apparatus - Google Patents

Description

  The present invention relates to an electrophotographic photosensitive member, an electrophotographic photosensitive member cartridge, and an image forming apparatus used for a copying machine, a printer, and the like.

  C. F. The electrophotographic technology invented by Carlson is not limited to the field of copiers, because it can provide images with immediacy, high quality and high storage stability. Has also become widespread and shows a huge spread. For photoconductors that are the core of electrophotographic technology, photoconductors that use organic photoconductive materials, which have the advantages of being non-polluting, easy to form and easy to manufacture, are mainly used. Is used. Above all, a so-called laminated photoreceptor in which a charge generation layer and a charge transport layer are laminated can provide a more sensitive photoreceptor, a wide range of material selection, and a highly safe photoreceptor. Since it is highly productive and relatively advantageous in terms of cost, it is now the mainstream of photoconductors and is produced in large quantities.

  On the other hand, digitization for image formation is rapidly progressing in order to obtain higher quality images and to store and edit input images freely. In the past, digital image formation has been limited to laser printers, LED printers, and some color laser copies, which are output devices of word processors and personal computers. Digitization was almost completely achieved even in the field of ordinary copying machines where mainstream image formation was the mainstream.

  When such digital image formation is performed, laser light or LED light is mainly used as a light input light source for digital signals to the photosensitive member. As a transmission wavelength of a light input light source that is widely used at present, near-infrared light of 780 nm or 660 nm and long-wavelength light close thereto are widely used. In recent years, blue lasers have been put into practical use, and it has become possible to use light having a short wavelength of 400 to 500 nm as a light source for light input. As a photoreceptor used for digital image formation, it is necessary to have an effective sensitivity to these various light input light sources, and various materials have been studied so far. In addition to high sensitivity, basic characteristics such as sufficient chargeability, low dark decay after charging, low residual potential, and good stability during repeated use of these characteristics, etc. Characteristics are required.

  In particular, in repeated use in a copying machine or printer, there is a problem that the photosensitive layer gradually deteriorates. Therefore, it is desired that damage due to repeated use is small and electrical characteristics are stable. These characteristics greatly depend on the charge generation material, the charge transport material, the additive, and the binder resin. As the charge generation material, a phthalocyanine pigment or an azo pigment is mainly used because it needs to have sensitivity to a light source for light input. Various types of charge transport materials are known, but amine compounds are widely used because they exhibit a very low residual potential (see, for example, Patent Document 1 and Patent Document 2). Various additives are known, but those having the effect of increasing ozone resistance are well known (see, for example, Patent Document 3 and Patent Document 4). Further, as the binder resin used for the photosensitive layer, particularly the charge transport layer, a polycarbonate resin or a polyarylate resin is preferably used (for example, see Patent Document 5).

Japanese Patent Laid-Open No. 2000-075517 JP 2002-040688 A Japanese Patent No. 2644278 Japanese Patent Laid-Open No. 9-265194 Japanese Patent Laid-Open No. 2000-075517

  With the recent increase in the speed of electrophotographic electrophotographic photoreceptors, higher sensitivity is required as a characteristic of electrophotographic photoreceptors. In addition, it is necessary to precisely design an electrophotographic photosensitive member suitable for various apparatus conditions such as a charging device, a light input light source, and a developing device. Even if a photoconductor is prepared according to the requirements and a good image can be formed at the beginning, the image may be deteriorated by repeated use over a long period of time. Met.

  The present invention has been made in view of the above-described problems, has excellent electrical characteristics, and is particularly suitable even when light in a wide wavelength range from a short wavelength to a long wavelength is used as a light input light source. The present invention provides an electrophotographic photosensitive member having electrical characteristics and capable of forming a good image even when used repeatedly for a long period of time, and an electrophotographic photosensitive member cartridge and image formation using the electrophotographic photosensitive member Is to provide a device.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the photosensitive layer contains an ester compound having a specific structure, which has favorable electrical characteristics and is good even when used repeatedly for a long time. The present inventors have found that an image can be formed and have completed the present invention.

［式（１）中、Ｒ^１、Ｒ^２は、炭素数３０以下の有機基を表し、Ｘは、炭素数３以上３０以下の飽和炭化水素基を表す］ That is, the present invention is an electrophotographic photoreceptor having a photosensitive layer on a conductive support, wherein the photosensitive layer contains at least one compound represented by the following formula (1). It exists in the electrophotographic photoreceptor.

[In formula (1), R ¹ and R ² represent an organic group having 30 or less carbon atoms, and X represents a saturated hydrocarbon group having 3 to 30 carbon atoms]

  The present invention also provides the above electrophotographic photosensitive member, a charging unit for charging the electrophotographic photosensitive member, an exposure unit for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image, and the electrophotographic photosensitive member on the electrophotographic photosensitive member. The electrophotographic photosensitive member cartridge is provided with at least one of a developing unit for developing the electrostatic latent image formed on the electrophotographic photosensitive member and a cleaning unit for cleaning the electrophotographic photosensitive member.

  The present invention also provides the electrophotographic photosensitive member described above, a charging unit for charging the electrophotographic photosensitive member, an exposure unit for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image, and the electrophotographic photosensitive member. And an image development apparatus for developing the electrostatic latent image formed on the image forming apparatus.

  According to the present invention, by using a photosensitive layer containing a specific compound, there is provided an electrophotographic photosensitive member having high sensitivity in a wide wavelength range and capable of forming a good image even when used repeatedly for a long period of time. can do. Further, by using the electrophotographic photosensitive member or using an electrophotographic photosensitive member cartridge using the electrophotographic photosensitive member, it is possible to perform suitable exposure with various light input light sources, and use repeatedly for a long period of time. Even if it does, the image forming apparatus which can form a favorable image can be provided.

1 is a schematic diagram illustrating a main configuration of an embodiment of an image forming apparatus of the present invention.

  Hereinafter, although an embodiment of the present invention is described in detail, the present invention is not limited to the following description, and can be appropriately modified and implemented without departing from the gist of the present invention.

[Electrophotographic photoreceptor]
If the electrophotographic photoreceptor of the present invention is provided with a photosensitive layer containing at least one kind of the compound represented by the following formula (1) in the present invention on a conductive support, the details thereof will be described. The configuration is not particularly limited. A typical configuration will be described below.

<Photosensitive layer>
The photosensitive layer is formed on a conductive support. When an undercoat layer described later is provided, the photosensitive layer is formed on the undercoat layer, and this case is also included in the meaning of “formed on the conductive support”. The type of the photosensitive layer is a single layer structure in which the charge generation material and the charge transport material are present in the same layer and dispersed in a binder resin (hereinafter, abbreviated as “single layer type photosensitive layer”). ), And a charge generation layer in which a charge generation material is dispersed in a binder resin and a charge transport layer in which a charge transport material is dispersed in a binder resin (hereinafter referred to as “ May be abbreviated as “laminated photosensitive layer”), but any form may be employed. In addition, as the laminated photosensitive layer, a charge generation layer and a charge transport layer are laminated in this order from the conductive support side, and a charge transport layer and a charge generation layer are laminated in this order. Although a reverse lamination type photosensitive layer is mentioned, any form can be adopted.

［式（１）中、Ｒ^１、Ｒ^２は、炭素数３０以下の有機基を表し、Ｘは、炭素数３以上３０以下の飽和炭化水素基を表す］ The photosensitive layer in the invention contains a compound represented by the following formula (1).

[In formula (1), R ¹ and R ² represent an organic group having 30 or less carbon atoms, and X represents a saturated hydrocarbon group having 3 to 30 carbon atoms]

  Although the compound represented by Formula (1) in this invention is contained in a photosensitive layer, it is preferable to be contained in the layer containing a charge transport substance. The compound represented by the formula (1) in the present invention is preferably used in an amount of 0.001 to 30 parts by mass, more preferably 0.01 parts by mass or more, with respect to 100 parts by mass of the binder. From the viewpoint of electrical characteristics, it is particularly preferably 0.1 parts by mass or more. Moreover, when there is too much, there exists a possibility that the effect of a charge transport agent or a charge generation agent may be scraped off, 20 mass parts or less are preferable, Especially preferably, it is 10 mass parts or less.

  In the present invention, when the photosensitive layer is formed of a plurality of layers, the compound represented by the formula (1) may be contained in any one of these layers, and different layers are different from each other. Although it may contain a compound, it is preferably contained in a layer that requires a function of transporting charges. Particularly preferably, the compound represented by the formula (1) is contained in the charge transport layer of the multilayer photosensitive layer.

R ¹ and R ² in the formula (1) represent an organic group having 30 or less carbon atoms. The number of carbon atoms is preferably 20 or less, more preferably 15 or less, and particularly preferably 10 or less. In addition, R ¹ and R ² in the formula (1) may contain a cyclic structure and are preferably a hydrocarbon group which may have a substituent. More preferred are an aryl group which may have a substituent and an alkyl group which may have a substituent.

Examples of the aryl group in R ¹ and R ² in the formula (1) include a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, a biphenylyl group, and a terphenylyl group, and preferably 3 or less aromatic rings. Particularly preferred is a phenyl group. Examples of the alkyl group in R ¹ and R ² in the formula (1) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a pentyl group, an isopentyl group, a neopentyl group, a 1-methylbutyl group, and a 1-methylheptyl group. , Alkyl groups such as dodecyl group, hexadecyl group, octadecyl group and the like, preferably having 10 or less carbon atoms, particularly preferably methyl group, ethyl group, cyclohexyl group or propyl group.

Examples of the substituent that R ¹ and R ^{2 in} formula (1) may have include, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a pentyl group, an isopentyl group, a neopentyl group, and a 1-methylbutyl group. Alkyl groups such as 1-methylheptyl group, dodecyl group, hexadecyl group and octadecyl group;
Aryl groups such as phenyl group, naphthyl group, anthryl group, pyrenyl group;
Aralkyl groups such as benzyl and phenethyl;
Alkoxy groups such as methoxy group and ethoxy group;
A hydroxy group;
A nitro group;
A halogen atom etc. are mentioned, Furthermore, you may have a substituent. Two substituents may be combined to form a ring, or may form a condensed ring. As the substituent, an alkyl group having 10 or less carbon atoms is preferable, and a methyl group is more preferable. A plurality of substituents may be present independently.

X represents a saturated hydrocarbon group having 3 to 30 carbon atoms. Specifically, it is a divalent group of a saturated hydrocarbon compound, for example, propane divalent group, butane divalent group, pentane divalent group, hexane divalent group, cyclohexane divalent group, octane divalent group, Examples thereof include a divalent group, a nonane divalent group, a decane divalent group, and a dodecane divalent group. A divalent group having 20 or less carbon atoms is preferable, and a divalent group having 15 or less is more preferable. Specifically, preferably a divalent group of butane, a divalent group of octane, a divalent group of dimethylcyclohexane, a divalent group of bicycloheptane, a divalent group of cyclohexane, a divalent group of spirooctane, etc. Those containing a structure are preferred. Specifically, those having a cyclohexane skeleton in the compound are preferable, and a divalent group of dimethylcyclohexane is particularly preferable. For example, the following structures are mentioned.

  Next, specific examples of the structure of the compound represented by the formula (1) in the present invention are illustrated. Hereinafter, these compounds are referred to as “Exemplary Compound 1 to Exemplary Compound 37” as appropriate. These are given for the purpose of explaining the present invention in detail, and are not limited to the following structures unless they are contrary to the gist of the present invention.

<Conductive support>
As the conductive support used in the electrophotographic photosensitive member of the present invention, for example, metal materials such as aluminum, aluminum alloy, stainless steel, copper and nickel, and conductive powders such as metal, carbon and tin oxide are added. Mainly used are resin materials provided with conductivity and resins, glass, paper, and the like obtained by depositing or coating a conductive material such as aluminum, nickel, ITO (indium tin oxide) on the surface. As a form, a drum shape, a sheet shape, a belt shape or the like is used. A conductive material having an appropriate resistance value may be applied to a conductive support made of a metal material in order to control conductivity, surface properties, etc. or to cover defects.

When a metal material such as an aluminum alloy is used as the conductive support, it may be used after an anodized film is applied. When an anodized film is applied, it is desirable to perform a sealing treatment by a known method. For example, an anodic oxidation film is formed by anodizing in an acidic bath such as chromic acid, sulfuric acid, oxalic acid, boric acid, sulfamic acid, etc. give. In the case of anodic oxidation in sulfuric acid, the sulfuric acid concentration is 100 to 300 g / L, the dissolved aluminum concentration is 2 to 15 g / L, the liquid temperature is 15 to 30 ° C., the electrolysis voltage is 10 to 20 V, and the current density is 0.5 to Although it is preferable to set within the range of ² A / dm ² , it is not limited to the above conditions.

  It is preferable to perform a sealing treatment on the anodic oxide film thus formed. The sealing treatment may be performed by a known method. For example, it is immersed in an aqueous solution containing nickel fluoride as a main component, or immersed in an aqueous solution containing nickel acetate as a main component. A high temperature sealing treatment is preferably performed.

  The concentration of the nickel fluoride aqueous solution used in the case of the low-temperature sealing treatment can be appropriately selected, but more preferable results are obtained when it is used in the range of 3 to 6 g / L. Moreover, in order to advance a sealing process smoothly, as processing temperature, it is 25-40 degreeC, Preferably it is 30-35 degreeC, Moreover, nickel fluoride aqueous solution pH is 4.5-6.5, Preferably it is 5 It is better to process in the range of .5 to 6.0. As the pH adjuster, oxalic acid, boric acid, formic acid, acetic acid, sodium hydroxide, sodium acetate, aqueous ammonia and the like can be used. The treatment time is preferably in the range of 1 to 3 minutes per 1 μm of film thickness. In order to further improve the physical properties of the film, cobalt fluoride, cobalt acetate, nickel sulfate, a surfactant or the like may be added to the nickel fluoride aqueous solution. Subsequently, it is washed with water and dried to finish the low temperature sealing treatment.

  As the sealing agent in the case of the high-temperature sealing treatment, for example, an aqueous metal salt solution such as nickel acetate, cobalt acetate, lead acetate, nickel acetate-cobalt, and barium nitrate can be used. In particular, nickel acetate is used. Is preferred. The concentration in the case of using an aqueous nickel acetate solution is preferably 5 to 20 g / L. The treatment temperature is 80 to 100 ° C., preferably 90 to 98 ° C., and the pH of the nickel acetate aqueous solution is preferably 5.0 to 6.0.

  Here, aqueous ammonia, sodium acetate, or the like can be used as the pH adjuster. The treatment time is 10 minutes or longer, preferably 20 minutes or longer. In this case as well, sodium acetate, organic carboxylic acid, anionic and nonionic surfactants may be added to the nickel acetate aqueous solution in order to improve the film properties. Subsequently, it is washed with water and dried to finish the high temperature sealing treatment. When the average film thickness is thick, stronger sealing conditions are required due to the higher concentration of the sealing liquid and high temperature / long-time treatment. Accordingly, productivity is deteriorated and surface defects such as spots, dirt, and dusting are likely to occur on the coating surface. From such a point, it is preferable that the average film thickness of the anodic oxide coating is usually 20 μm or less, particularly 7 μm or less.

  The support surface may be smooth, or may be roughened by using a special cutting method or polishing. Further, it may be roughened by mixing particles having an appropriate particle diameter with the material constituting the support. In order to reduce the cost, it is possible to use the drawing tube as it is without cutting. Especially when using non-cutting aluminum supports such as drawing, impact processing, ironing, etc., the process eliminates dirt, foreign matter, etc. on the surface, small scratches, etc., and a uniform and clean support can be obtained. Therefore, it is preferable.

<Underlayer>
As the undercoat layer, a resin, a resin in which particles such as a metal oxide are dispersed, or the like is used. In particular, the metal oxide particles are preferably formed in a form dispersed in a binder resin. The mixing ratio of the inorganic particles to the binder resin can be arbitrarily selected, but it is preferably used in the range of 10% by mass to 500% by mass in terms of stability of the dispersion and coatability.

  The thickness of the undercoat layer can be arbitrarily selected, but is preferably 0.1 μm to 20 μm in view of electrophotographic photoreceptor characteristics and coating properties. The undercoat layer may contain a known antioxidant or the like.

  Moreover, the volume average particle | grains of the metal oxide particle measured by the dynamic light scattering method in the liquid which disperse | distributed this undercoat layer to the solvent which mixed methanol and 1-propanol by the mass ratio of 7: 3. The diameter is 0.1 μm or less, preferably 95 nm or less, more preferably 90 nm or less. Although there is no restriction | limiting in particular in the minimum of a volume average particle diameter, Usually, it is 20 nm or more. By satisfying the above range, the electrophotographic photosensitive member of the present invention has stable exposure-charging repeat characteristics under low temperature and low humidity, and suppresses occurrence of image defects such as black spots and color spots in the obtained image. it can.

  Similarly, the cumulative 90% particle diameter accumulated from the small particle diameter side of the metal oxide particles is 0.3 μm or less, preferably 0.2 μm or less, more preferably 0.15 μm or less. In a conventional electrophotographic photoreceptor, the undercoat layer contains metal oxide particles that are large enough to penetrate the front and back of the undercoat layer in some cases, and the large metal oxide particles may cause defects during image formation. It was. Further, when a contact type is used as the charging means, when the photosensitive layer is charged, the charge is transferred from the conductive substrate to the photosensitive layer through the metal oxide particles, so that the charging is appropriately performed. In some cases, it became impossible. However, by reducing the cumulative 90% particle size, it is possible to reduce the number of large metal oxide particles that cause defects as described above. As a result, in the electrophotographic photosensitive member of the present invention, it is possible to suppress the occurrence of defects and the inability to appropriately charge, and high-quality image formation is possible.

  The metal oxide particles in the undercoat layer are preferably present as primary particles. However, there are few such cases, and in most cases, they are aggregated and exist as aggregate secondary particles, or both are mixed. Therefore, how the size distribution of the metal oxide particles in the undercoat layer should be very important. Although it is very difficult to directly evaluate the particle size distribution of the metal oxide particles in the undercoat layer, by dispersing the undercoat layer in a specific solvent and evaluating the dispersion, The particle size distribution of the metal oxide particles can be known.

  The subbing layer is 90% cumulative from the volume average particle diameter and the small particle diameter side of the metal oxide particles in a liquid in which methanol and 1-propanol are mixed in a solvent mixed at a mass ratio of 7: 3. As the particle diameter, a value measured by a dynamic light scattering method can be used regardless of the existence form of the metal oxide particles.

  In the dynamic light scattering method, the speed of Brownian motion of finely dispersed particles is detected, and the particle size distribution is detected by irradiating the particles with laser light and detecting light scattering (Doppler shift) with different phases according to the speed. Is what you want. The value of the volume average particle diameter of the metal oxide particles in the undercoat layer in the present invention is such that the metal oxide particles are stably dispersed in a solvent in which methanol and 1-propanol are mixed at a mass ratio of 7: 3. And does not mean the particle size of metal oxide particles or the like as powder before dispersion. In the actual measurement, a dynamic light scattering type particle size analyzer (manufactured by Nikkiso Co., Ltd., MICROTRAC UPA model: 9340-UPA, hereinafter abbreviated as UPA) is used under the following measurement conditions. A specific measurement operation is performed based on the instruction manual of the particle size analyzer (manufactured by Nikkiso Co., Ltd., Document No. T15-490A00, revised No. E).

The measurement conditions of the dynamic light scattering particle size analyzer are as follows.
Measurement upper limit: 5.9978 μm
Measurement lower limit: 0.0035 μm
Number of channels: 44
Measurement time: 300 sec.
Measurement temperature: 25 ° C
Particle permeability: Absorption Particle refractive index: N / A (not applicable)
Particle shape: non-spherical density: 4.20 (g / cm ³ ) (*)
Dispersion medium type: Mixed solvent of methanol and 1-propanol (mass ratio: methanol / 1-propanol = 7/3)
Dispersion medium refractive index: 1.35
(*) The value of density is for titanium dioxide particles, and for other particles, the values described in the instruction manual are used.

  In addition, when the liquid which disperse | distributed the undercoat layer to the solvent which mixed methanol and 1-propanol by the mass ratio of 7: 3 is too thick, and the density | concentration is outside the measurable range of a measuring device. The coating solution for forming the undercoat layer is diluted with a mixed solvent of methanol and 1-propanol (methanol / 1-propanol = 7/3 (mass ratio); refractive index = 1.35), and the concentration is measured by a measuring device. Try to be within the possible range. For example, in the case of the above UPA, the sample is diluted with a mixed solvent of methanol and 1-propanol so that a sample concentration index (SIGNAL LEVEL) suitable for measurement is 0.6 to 0.8.

  Even if the dilution is performed in this way, it is considered that the particle diameter of the metal oxide particles in the liquid in which the undercoat layer is dispersed does not change. Therefore, the volume average particle diameter measured as a result of the dilution is measured. The 90% cumulative particle size is measured in a liquid in which the undercoat layer in the present invention is dispersed in a solvent in which methanol and 1-propanol are mixed at a mass ratio of 7: 3. It shall be handled as a diameter.

  As the metal oxide particles contained in the undercoat layer, any metal oxide particles that can be used for an electrophotographic photoreceptor can be used. Specific examples of metal oxides forming the metal oxide particles include metal oxides containing one metal element such as titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, zinc oxide and iron oxide; calcium titanate And metal oxides containing a plurality of metal elements such as strontium titanate and barium titanate. Among these, metal oxide particles made of a metal oxide having a band gap of 2 to 4 eV are preferable. If the band gap is too small, carrier injection from the conductive support is likely to occur, and defects such as black spots and color spots may easily occur when an image is formed. If the band gap is too large, In some cases, the trapping of the metal hinders the movement of charges and deteriorates the electrical characteristics.

  Among the metal oxides forming these metal oxide particles, titanium oxide, aluminum oxide, silicon oxide and zinc oxide are preferable, titanium oxide and aluminum oxide are more preferable, and titanium oxide is still more preferable. In addition, only 1 type of particle | grains may be used for a metal oxide particle, and several types of particle | grains may be used together by arbitrary combinations and ratios. In addition, the metal oxide particles may be formed from only one kind of metal oxide, or may be formed by using two or more kinds of metal oxides in any combination and ratio. Good.

  The crystal form of the metal oxide particles is arbitrary as long as the effects of the present invention are not significantly impaired. For example, the crystal type of metal oxide particles using titanium oxide as a metal oxide (that is, titanium oxide particles) is not limited, and any of rutile, anatase, brookite, and amorphous can be used. Further, the crystal form of the titanium oxide particles may include those in a plurality of crystal states from those having different crystal states.

  Further, the surface of the metal oxide particles may be subjected to various surface treatments. For example, treatment with a treating agent such as an inorganic substance such as tin oxide, aluminum oxide, antimony oxide, zirconium oxide, or silicon oxide, or an organic substance such as stearic acid, polyol, or organosilicon compound may be performed.

  In particular, when titanium oxide particles are used as the metal oxide particles, the surface treatment is preferably performed with an organosilicon compound. Examples of the organosilicon compound include silicone oils such as dimethylpolysiloxane and methylhydrogenpolysiloxane; organosilanes such as methyldimethoxysilane and diphenyldidimethoxysilane; silazanes such as hexamethyldisilazane; vinyltrimethoxysilane and γ-mercapto. Examples include silane coupling agents such as propyltrimethoxysilane and γ-aminopropyltriethoxysilane.

前記式（ｉ）中、Ｒ^u１及びＲ^u２は、それぞれ独立してアルキル基を表す。Ｒ^u１及びＲ^u２の炭素数に制限は無いが、通常１以上であって、通常１８以下、好ましくは１０以下、より好ましくは６以下で、特に好ましくは３以下である。これにより、金属酸化物粒子との反応性が好適になるという利点が得られる。炭素数が多くなりすぎると、金属酸化物粒子との反応性が低下したり、処理後の金属酸化物粒子の塗布液中での分散安定性が低下したりする場合がある。 The metal oxide particles are particularly preferably treated with a silane treating agent represented by the structure of the following formula (i). This silane treatment agent is a good treatment agent with good reactivity with metal oxide particles.

In the formula (i), R ^u1 and R ^u2 each independently represents an alkyl group. The number of carbon atoms of R ^u1 and R ^u2 is not limited, but is usually 1 or more, usually 18 or less, preferably 10 or less, more preferably 6 or less, and particularly preferably 3 or less. Thereby, the advantage that the reactivity with a metal oxide particle becomes suitable is acquired. When the number of carbon atoms is excessively increased, the reactivity with the metal oxide particles may decrease, or the dispersion stability of the treated metal oxide particles in the coating solution may decrease.

Examples of R ^u1 and R ^u2 include a methyl group, an ethyl group, and a propyl group. In the formula (i), R ^u3 represents an alkyl group or an alkoxy group. Although there is no restriction ^| limiting in carbon number of ^Ru3 , Usually, it is 1 or more, and usually 18 or less, Preferably it is 10 or less, More preferably, it is 6 or less, Especially it is 3 or less. Thereby, the advantage that the reactivity with a metal oxide particle becomes suitable is acquired. When the number of carbon atoms is excessively increased, the reactivity with the metal oxide particles may decrease, or the dispersion stability of the treated metal oxide particles in the coating solution may decrease.

Examples of R ^u3 include a methyl group, an ethyl group, a methoxy group, and an ethoxy group. In addition, the outermost surface of these surface-treated metal oxide particles is usually treated with the treatment agent as described above. At this time, the surface treatment described above may be performed only by one surface treatment, or two or more surface treatments may be performed in any combination. For example, it may be treated with a treating agent such as aluminum oxide, silicon oxide or zirconium oxide before the surface treatment with the silane treating agent represented by the above formula (i). Moreover, you may use together the metal oxide particle which performed different surface treatment in arbitrary combinations and a ratio.

  There is no restriction | limiting in the average primary particle diameter of the metal oxide particle in this invention, As long as the effect of this invention is not impaired remarkably, it is arbitrary. However, the average primary particle diameter of the metal oxide particles in the present invention is usually 1 nm or more, preferably 5 nm or more, and usually 100 nm or less, preferably 70 nm or less, more preferably 50 nm or less. The average primary particle diameter is defined as a value obtained by an arithmetic average value of particle diameters directly observed by a transmission electron microscope (hereinafter referred to as “TEM” as appropriate).

  Moreover, there is no restriction | limiting in the refractive index of the metal oxide particle in this invention, What kind of thing can be used if it can be used for an electrophotographic photoreceptor. The refractive index of the metal oxide particles in the present invention is usually 1.3 or more, preferably 1.4 or more, more preferably 1.5 or more, and usually 3.0 or less, preferably 2.9 or less, more preferably. Is 2.8 or less.

  In the coating liquid for forming the undercoat layer in the present invention, the use ratio of the metal oxide particles and the binder resin is arbitrary as long as the effects of the present invention are not significantly impaired. However, in the coating liquid for forming the undercoat layer in the present invention, the metal oxide particles are usually 0.5 parts by mass or more, preferably 0.7 parts by mass or more, with respect to 1 part by mass of the binder resin. More preferably, it is used in the range of 1.0 part by mass or more, usually 4 parts by mass or less, preferably 3.8 parts by mass or less, more preferably 3.5 parts by mass or less. If the amount of the metal oxide particles is too small relative to the binder resin, the electrical characteristics of the electrophotographic photosensitive member may be deteriorated, and the residual potential may be increased. Moreover, when there are too many metal oxide particles with respect to binder resin, the image defects, such as the black spot of the image formed using the said electrophotographic photoreceptor, and a color point, may increase.

  Any binder resin can be used as the binder resin contained in the undercoat layer as long as the effects of the present invention are not significantly impaired. Usually, any binder resin usable for an electrophotographic photosensitive member can be used. Usually, it is soluble in a solvent such as an organic solvent, and the undercoat layer after formation is insoluble or low in solubility in a solvent such as an organic solvent used in a coating solution for forming a photosensitive layer. Use a material that does not substantially mix. As such a binder resin, for example, a resin such as phenoxy, epoxy, polyvinyl pyrrolidone, polyvinyl alcohol, casein, polyacrylic acid, cellulose, gelatin, starch, polyurethane, polyimide, polyamide or the like is cured alone or with a curing agent. Can be used in Of these, polyamide resins such as alcohol-soluble copolymerized polyamides and modified polyamides are preferable in that they exhibit good dispersibility and coatability.

  As the polyamide resin, for example, so-called copolymer nylon obtained by copolymerizing 6-nylon, 66-nylon, 610-nylon, 11-nylon, 12-nylon, etc .; N-alkoxymethyl-modified nylon, N-alkoxyethyl-modified Examples thereof include alcohol-soluble nylon resins such as a type obtained by chemically modifying nylon such as nylon.

Among these polyamide resins, a copolymerized polyamide containing a diamine component corresponding to the diamine represented by the following formula (ii) (hereinafter sometimes abbreviated as “diamine component corresponding to formula (ii)”) as a constituent component Resins are particularly preferably used.

In the formula (ii), R ^u4 ~R ^u7 represents a hydrogen atom or an organic substituent. a and b each independently represents an integer of 0 to 4; When there are a plurality of substituents, these substituents may be the same as or different from each other.

The organic substituent represented by R ^u4 to R ^u7, for example, hydrocarbon group which may contain a hetero atom. Among these, preferred are, for example, alkyl groups such as methyl group, ethyl group, n-propyl group and isopropyl group; alkoxy groups such as methoxy group, ethoxy group, n-propoxy group and isopropoxy group; phenyl group and naphthyl group Group, anthryl group, and aryl group such as pyrenyl group, and the like, more preferably alkyl group and alkoxy group. Particularly preferred are a methyl group and an ethyl group.

Although the carbon number of the organic substituent represented by R ^u4 to R ^u7 is optional unless significantly impairing the effects of the present invention, usually 20 or less, preferably 18 or less, more preferably 12 or less, and usually 1 or more. If the number of carbon atoms is too large, the solubility in the solvent may deteriorate and the coating solution may gel, or the coating solution may become cloudy or gel with the passage of time even if temporarily dissolved.

  The copolymerized polyamide resin containing a diamine component corresponding to the formula (ii) as a constituent component may be abbreviated as a constituent component other than the diamine component corresponding to the formula (ii) (hereinafter referred to as “other polyamide constituent components”). ) As a structural unit. Examples of other polyamide constituents include lactams such as γ-butyrolactam, ε-caprolactam, lauryllactam; 1,4-butanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,20-eicosanedicarboxylic acid, and the like. Dicarboxylic acids; diamines such as 1,4-butanediamine, 1,6-hexamethylenediamine, 1,8-octamethylenediamine, 1,12-dodecanediamine; piperazine and the like. At this time, examples of the copolymerized polyamide resin include those obtained by copolymerizing the constituent components into, for example, binary, ternary, and quaternary.

  When the copolymerized polyamide resin containing the diamine component corresponding to the formula (ii) as a constituent component contains other polyamide constituent components as constituent units, the proportion of the diamine component corresponding to the formula (ii) in all the constituent components Although there is no limitation, it is usually 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, and usually 40 mol% or less, preferably 30 mol% or less. If the diamine component corresponding to formula (ii) is too much, the stability of the coating solution may be deteriorated. If it is too little, the change in electrical characteristics under high sound and high humidity conditions becomes large, and the stability of the electrical characteristics against environmental changes is increased. May be worse.

Specific examples of the copolymerized polyamide resin are shown below. However, in specific examples, the copolymerization ratio represents the charge ratio (molar ratio) of the monomer.

  There is no restriction | limiting in particular in the manufacturing method of the said copolyamide, The normal polycondensation method of polyamide is utilized suitably. For example, a polycondensation method such as a melt polymerization method, a solution polymerization method, and an interfacial polymerization method can be used as appropriate. In the polymerization, for example, a monobasic acid such as acetic acid or benzoic acid; a monoacid base such as hexylamine or aniline may be contained in the polymerization system as a molecular weight regulator.

  In addition, the said binder resin may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  Moreover, there is no restriction | limiting also in the number average molecular weight of binder resin. For example, when a copolymerized polyamide is used as the binder resin, the number average molecular weight of the copolymerized polyamide is usually 10,000 or more, preferably 15000 or more, and usually 50000 or less, preferably 35000 or less. Even if the number average molecular weight is too small or too large, it may be difficult to maintain the uniformity of the undercoat layer.

  The undercoat layer is usually obtained by applying and forming a coating solution for forming the undercoat layer. Various physical properties of the undercoat layer are affected by the physical properties of the coating solution for forming the undercoat layer. The content of the binder resin in the coating solution is arbitrary as long as the effects of the present invention are not significantly impaired. However, the content of the binder resin in the coating solution for forming the undercoat layer of the present invention is usually 0.5% by mass or more, preferably 1% by mass or more, and usually 20% by mass or less, preferably 10%. Used in the range of mass% or less. Usually, the coating liquid for forming the undercoat layer is obtained by dissolving or dispersing the components constituting the undercoat layer in a solvent.

  As the solvent used in the coating liquid for forming the undercoat layer in the present invention, any solvent can be used as long as it can dissolve the binder resin in the present invention. As this solvent, an organic solvent is usually used. Examples of the solvent used in the coating solution for forming the undercoat layer include, for example, alcohols having 5 or less carbon atoms such as methanol, ethanol, 1-propanol or 2-propanol; chloroform, 1,2-dichloroethane, dichloromethane Halogenated hydrocarbons such as trichrene, carbon tetrachloride and 1,2-dichloropropane; nitrogen-containing organic solvents such as dimethylformamide; aromatic hydrocarbons such as toluene and xylene.

  Moreover, the solvent used for the coating liquid for forming the said undercoat layer may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio. Furthermore, even if the solvent alone does not dissolve the binder resin in the present invention, it is used as long as the binder resin can be dissolved by using a mixed solvent with another solvent (for example, the organic solvent exemplified above). be able to. In general, coating unevenness can be reduced by using a mixed solvent.

  In the coating liquid for forming the undercoat layer in the present invention, the amount ratio of the solvent and the solid content of the metal oxide particles, the binder resin, etc. varies depending on the coating method of the coating liquid for forming the undercoat layer. The application method to be applied may be appropriately changed so that a uniform coating film is formed.

  Moreover, the coating liquid for forming the undercoat layer may contain components other than the metal oxide particles, the binder resin, and the solvent described above as long as the effects of the present invention are not significantly impaired. For example, the coating liquid for forming the undercoat layer may contain additives as other components. Examples of the additive include sodium phosphite, sodium hypophosphite, phosphorous acid, hypophosphorous acid, heat stabilizers typified by hindered phenol, and other polymerization additives. In addition, an additive may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  There is no restriction | limiting in particular in the manufacturing method of the coating liquid for forming an undercoat layer. However, the coating liquid for forming the undercoat layer contains metal oxide particles as described above, and the metal oxide particles are dispersed in the coating liquid for forming the undercoat layer. To do. Therefore, the manufacturing method of the coating liquid for forming the undercoat layer in the present invention usually has a dispersion step of dispersing the metal oxide particles.

<Layer containing charge generation material>
(1. Charge generation material)
In the electrophotographic photosensitive member of the present invention, any known compound can be used as the charge generating substance as long as the effect of the present invention is not hindered, and the combined use is not hindered. Examples of this include, for example, selenium and its alloys, cadmium sulfide, other inorganic photoconductive materials, phthalocyanine pigments, azo pigments, dithioketopyrrolopyrrole pigments, squalene pigments, quinacridone pigments, indigo pigments, perylene pigments, many Various photoconductive materials such as organic pigments such as ring quinone pigments, anthanthrone pigments and benzimidazole pigments can be used, preferably organic pigments, more preferably phthalocyanine pigments and azo pigments.

  Examples of the phthalocyanine used include metal-free phthalocyanine, copper, indium, gallium, tin, titanium, zinc, vanadium, silicon, germanium, and other metals or their oxides, halides, hydroxides, alkoxides, and the like. And various crystal types of phthalocyanines. Preferably, titanyl phthalocyanine (also known as oxy: oxy) such as X-type, τ-type metal-free phthalocyanine, A-type (also known as β-type), B-type (also known as α-type), and D-type (also known as Y-type), which are highly sensitive crystal forms Titanium phthalocyanine), vanadyl phthalocyanine, chloroindium phthalocyanine, chlorogallium phthalocyanine such as type II, hydroxygallium phthalocyanine such as V type, μ-oxo-gallium phthalocyanine dimer such as G type and I, μ- such as type II Oxo-aluminum phthalocyanine dimer. Among these phthalocyanines, A-type (β-type), B-type (α-type), D-type (Y-type) oxytitanium phthalocyanine, II-type chlorogallium phthalocyanine, V-type hydroxygallium phthalocyanine, G-type μ-oxo-gallium phthalocyanine Dimers and the like are more preferable. Particularly preferably, oxytitanium phthalocyanine and CuKα having a clear diffraction peak whose Bragg angle (2θ ± 0.2 °) is mainly 27.3 ° in a powder X-ray diffraction spectrum of CuOα characteristic X-ray of the oxytitanium dysocyanine. In the powder X-ray diffraction spectrum by characteristic X-ray, the oxytitanium di-cyanine having a clear diffraction peak at a Bragg angle (2θ ± 0.2 °) of 9.0 ° to 9.7 °. Examples of preferable azo compounds are described below.

(2. Multilayer photoreceptor)
When the electrophotographic photoreceptor of the present invention is a so-called multilayer photoreceptor, the layer containing the charge generating substance is usually a charge generating layer. However, in the multilayer photoconductor, a charge generating material may be contained in the charge transport layer as long as the effects of the present invention are not significantly impaired.

  There is no restriction on the volume average particle size of the charge generating material. However, when used in a multilayer photoreceptor, the volume average particle diameter of the charge generating material is usually 1 μm or less, preferably 0.5 μm or less. The volume average particle diameter of the charge generation material can be measured in the same manner as the volume average diameter of the metal oxide particles contained in the undercoat layer in the present invention, or a known laser diffraction scattering method. Is defined by a particle size analysis device by means of, or a particle size analysis device by light transmission centrifugal sedimentation.

  The thickness of the charge generation layer is arbitrary, but is usually 0.1 μm or more, preferably 0.15 μm or more, and usually 2 μm or less, preferably 0.8 μm or less.

  When the layer containing the charge generation material is a charge generation layer, the usage ratio of the charge generation material in the charge generation layer is usually 30 masses per 100 mass parts of the binder resin for photosensitive layer contained in the charge generation layer. Part or more, preferably 50 parts by weight or more, and usually 500 parts by weight or less, preferably 300 parts by weight or less. If the amount of the charge generating substance used is too small, the electrical characteristics as an electrophotographic photosensitive member may not be sufficient, and if it is too large, the stability of the coating solution may be impaired.

  Furthermore, in the charge generation layer, known plasticizers for improving film formability, flexibility, mechanical strength, etc., additives for suppressing residual potential, and dispersion aids for improving dispersion stability Further, it may contain a leveling agent, a surfactant, silicone oil, fluorine oil and other additives for improving coating properties. In addition, these additives may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

(3. Single layer type photoreceptor)
When the electrophotographic photoreceptor of the present invention is a so-called single-layer photoreceptor, the matrix mainly composed of a binder resin for a photosensitive layer and a charge transport material having the same blending ratio as the charge transport layer described later, The charge generating material is dispersed. When used in a single layer type photosensitive layer, the particle size of the charge generating material is preferably sufficiently small. Therefore, in the single-layer type photosensitive layer, the volume average particle diameter of the charge generation material is usually 0.5 μm or less, preferably 0.3 μm or less.

  The thickness of the single-layer type photosensitive layer is arbitrary, but is usually 5 μm or more, preferably 10 μm or more, and usually 50 μm or less, preferably 45 μm or less.

  The amount of the charge generating material dispersed in the photosensitive layer is arbitrary. However, if the amount is too small, sufficient sensitivity may not be obtained. If the amount is too large, chargeability and sensitivity may be decreased. Therefore, the content of the charge generating substance in the single-layer type photosensitive layer is usually 0.5% by mass or more, preferably 10% by mass or more, and usually 50% by mass or less, preferably 45% by mass or less.

  In addition, the photosensitive layer of the single-layer type photoreceptor is also a known plasticizer for improving film formability, flexibility, mechanical strength, etc., an additive for suppressing residual potential, and an improvement in dispersion stability. It may contain a dispersion aid, a leveling agent for improving coating properties, a surfactant, silicone oil, fluorine oil and other additives. In addition, these additives may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

<Layer containing charge transport material>
(1. Charge transport material)
As the charge transporting substance, any known compound can be used as long as it does not interfere with the effect of the present invention as long as it is a substance that transports charges. More specifically, for example, diphenoquinone derivatives, aromatic nitro compounds such as 2,4,7-trinitrofluorenone, carbazole derivatives, indole derivatives, imidazole derivatives, oxazole derivatives, pyrazole derivatives, oxadiazole derivatives, pyrazoline derivatives, Heterocyclic compounds such as thiodiazole derivatives, aniline derivatives, compounds having a hydrazone structure, compounds having a diamine structure, nitrogen-containing compounds such as aromatic amine derivatives, stilbene derivatives, butadiene derivatives, enamine compounds, multiple combinations of these compounds Or a polymer having a group consisting of these compounds in the main chain or side chain.

Further, in the laminated type photoconductor, a compound having no absorption in the exposed region is preferable. Specific preferred examples include compounds having the following skeleton. These skeletons may be substituted with one or more substituents having 30 or less carbon atoms. Preferably, it is a substituent having 20 or less carbon atoms. As the substituent, an alkyl group, an aryl group, an alkoxy group, an unsaturated group or the like which may have a substituent is preferable.

Particularly preferred are hydrazone compounds (compounds having a hydrazone structure), diamine compounds (compounds having a diamine structure), and butadiene compounds (compounds having a butadiene structure). Moreover, the compound which has a structure below is still more preferable at the point which is excellent in matching with the compound represented by Formula (1).

Specific examples of preferred charge transport materials in the present invention are given below.

<Configuration of electrophotographic photoreceptor>
In the case of a multilayer photoreceptor, a charge transport layer containing a charge transport material is formed. The charge transport layer may be a single layer or a stack of a plurality of layers having different constituent components or composition ratios. Further, in the photosensitive layer of the single layer type photoreceptor, the charge generating material is dispersed in the charge transport medium having the same configuration as that of the charge transport layer of the multilayer photoreceptor. The charge transport layer of the multilayer photoreceptor and the charge transport medium of the single layer photoreceptor are usually obtained by binding these charge transport materials with a binder resin.

  Since the sequential layer type photoreceptor and the single layer type photoreceptor function when the light passing through the charge transport layer or the photosensitive layer reaches the charge generation material, the charge transport layer and the charge transport medium do not block the exposure light. It is necessary that the exposure light transmission is excellent, and the charge transporting material and the binder resin are preferably highly compatible, and the constituent materials do not precipitate or cause turbidity. Further, in order to form a good image, those that do not absorb exposure light are preferable, and the transmittance of exposure light of the charge transport layer or charge transport medium is preferably 87% or more, more preferably 90% or more. More preferably, it is 93% or more, and particularly preferably 95% or more. The exposure light transmittance of the charge transport layer or the charge transport medium can be achieved by selecting the charge transport material, for example, using the compound represented by the formula (1) in the present invention as the charge transport material. It can also be achieved by adjusting the thickness of the charge transport layer. Any known method can be used for measuring the transmittance of exposure light. For example, the layer is formed on a transparent plate (for example, a quartz glass plate) at a measurement wavelength, and is commercially available. It can be measured by a meter.

  In the charge transport layer of the multilayer photoreceptor and the photosensitive layer of the single-layer photoreceptor, the content ratio of the binder resin and the charge transport material is usually 30 to 200 parts by mass of the total charge transport material with respect to 100 parts by mass of the binder resin. , Preferably it is the range of 40-150 mass parts. The film thickness of the charge transport layer of the multilayer photoreceptor and the photosensitive layer of the single-layer photoreceptor is usually 5 to 50 μm, preferably 10 to 45 μm. If the film thickness becomes too thin, the life of the electrophotographic photosensitive member may be shortened due to wear, and if the film thickness becomes too thick, the resolution of the image may deteriorate due to diffusion of exposure light or charge.

<Additives>
In order to improve film forming properties, flexibility, coating properties, stain resistance, gas resistance, light resistance, etc., well-known plasticizers, antioxidants, ultraviolet absorbers, electron-withdrawing compounds, leveling agents, Surfactants and plasticizers such as silicone oil, fluorine oil and other additives may be included. Examples of the antioxidant include hindered phenol compounds and (hindered) amine compounds.

<Binder resin for photosensitive layer>
Examples of the binder resin used for the charge transport layer of the laminated photoreceptor and the photosensitive layer of the single-layer photoreceptor include, for example, vinyl polymers such as polymethyl methacrylate, polystyrene, and polyvinyl chloride and copolymers thereof, polycarbonate, Examples thereof include polyester, polyester carbonate, polysulfone, polyimide, phenoxy resin, epoxy resin, and silicone resin, and these partially crosslinked cured products or a mixture thereof may be used.

In the photosensitive layer of the present invention, preferred binder resins include polycarbonate resins and polyester resins. Polycarbonate resins and polyester resins generally have a partial structure of a diol component. Examples of diol components that form these structures include bisphenol residues, biphenol residues, and the like. Specific examples thereof include, for example,
Bis- (4-hydroxy-3,5-dimethylphenyl) methane, bis- (4-hydroxyphenyl) methane, bis- (4-hydroxy-3-methylphenyl) methane, 1,1-bis- (4-hydroxy) Phenyl) ethane, 1,1-bis- (4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxy-3-methylphenyl) propane, 2,2-bis- (4-hydroxyphenyl) butane, 2,2-bis- (4-hydroxyphenyl) pentane, 2,2-bis- (4-hydroxyphenyl) -3-methylbutane, 2,2-bis -(4-hydroxyphenyl) hexane, 2,2-bis- (4-hydroxyphenyl) -4-methylpentane, 1,1-bis- (4-hydroxyphenyl) ) Cyclopentane, 1,1-bis- (4-hydroxyphenyl) cyclohexane, bis- (3-phenyl-4-hydroxyphenyl) methane, 1,1-bis- (3-phenyl-4-hydroxyphenyl) ethane, 1,1-bis- (3-phenyl-4-hydroxyphenyl) propane, 2,2-bis- (3-phenyl-4-hydroxyphenyl) propane, 1,1-bis- (4-hydroxy-3-methyl) Phenyl) ethane, 2,2-bis- (4-hydroxy-3-methylphenyl) propane, 2,2-bis- (4-hydroxy-3-ethylphenyl) propane, 2,2-bis- (4-hydroxy) -3-isopropylphenyl) propane, 2,2-bis- (4-hydroxy-3-sec-butylphenyl) propane, 1,1-bis- (4-hydride) Xyl-3,5-dimethylphenyl) ethane, 2,2-bis- (4-hydroxy-3,5-dimethylphenyl) propane, 1,1-bis (4-hydroxy-3,5-dimethylphenyl) cyclohexane, 1,1-bis- (4-hydroxy-3,6-dimethylphenyl) ethane, bis- (4-hydroxy-2,3,5-trimethylphenyl) methane, 1,1-bis- (4-hydroxy-2) , 3,5-trimethylphenyl) ethane, 2,2-bis- (4-hydroxy-2,3,5-trimethylphenyl) propane, bis- (4-hydroxy-2,3,5-trimethylphenyl) phenylmethane 1,1-bis- (4-hydroxy-2,3,5-trimethylphenyl) phenylethane, 1,1-bis- (4-hydroxy-2,3,5-trimethylphene) Nyl) cyclohexane, bis- (4-hydroxyphenyl) phenylmethane, 1,1-bis- (4-hydroxyphenyl) -1-phenylethane, 1,1-bis- (4-hydroxyphenyl) -1-phenylpropane Bis- (4-hydroxyphenyl) diphenylmethane, bis- (4-hydroxyphenyl) dibenzylmethane, 4,4 ′-[1,4-fluoro
Eneylenebis (1-methylethylidene)] bis- [phenol], 4,4 ′-[1,4-phenylenebismethylene] bis- [phenol], 4,4 ′-[1,4-phenylenebis (1-methyl) Ethylidene)] bis- [2,6-dimethylphenol], 4,4 ′-[1,4-phenylenebismethylene] bis- [2,6-dimethylphenol], 4,4 ′-[1,4-phenylene Bismethylene] bis- [2,3,6-trimethylphenol], 4,4 ′-[1,4-phenylenebis (1-methylethylidene)] bis- [2,3,6-trimethylphenol], 4, 4 ′-[1,3-phenylenebis (1-methylethylidene)] bis- [2,3,6-trimethylphenol], 4,4′-dihydroxydiphenyl ether, 4,4-bis (4-hydroxyphenyl) yoshi Herbic acid stearyl ester, 4, 4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfide, 3,3 ', 5,5'-tetramethyl-4,4'-dihydroxydiphenyl ether, 3,3', 5,5'-tetramethyl- 4,4′-dihydroxydiphenylsulfone, 3,3 ′, 5,5′-tetramethyl-4,4′-dihydroxydiphenyl sulfide, phenolphthalein, 4,4 ′-[1,4-phenylenebis (1- Methylvinylidene)] bisphenol, 4,4 ′-[1,4-phenylenebis (1-methylvinylidene)] bis [2-methylphenol], (2-hydroxyphenyl) (4-hydroxyphenyl) methane, (2- Hydroxy-5-methylphenyl) (4-hydroxy-3-methylphenyl) methane, 1,1- (2-hydroxyphenyl) (4-hydro Bisphenol components such as xylphenyl) ethane, 2,2- (2-hydroxyphenyl) (4-hydroxyphenyl) propane, 1,1- (2-hydroxyphenyl) (4-hydroxyphenyl) propane,
4,4′-biphenol, 2,4′-biphenol, 3,3′-dimethyl-4,4′-dihydroxy-1,1′-biphenyl, 3,3′-dimethyl-2,4′-dihydroxy-1 , 1′-biphenyl, 3,3′-di- (t-butyl) -4,4′-dihydroxy-1,1′-biphenyl, 3,3 ′, 5,5′-tetramethyl-4,4 ′ -Dihydroxy-1,1'-biphenyl, 3,3 ', 5,5'-tetra- (t-butyl) -4,4'-dihydroxy-1,1'-biphenyl, 2,2', 3,3 Examples include biphenol components such as', 5,5'-hexamethyl-4,4'-dihydroxy-1,1'-biphenyl.

  Among these, preferred compounds are bis- (4-hydroxy-3,5-dimethylphenyl) methane, bis- (4-hydroxyphenyl) methane, bis- (4-hydroxy-3-methylphenyl) methane, 2, 2-bis- (4-hydroxy-3-methylphenyl) propane, 1,1-bis- (4-hydroxyphenyl) ethane, 2,2-bis- (4-hydroxyphenyl) propane, 2-hydroxyphenyl (4 Bisphenol components such as -hydroxyphenyl) methane and 2,2- (2-hydroxyphenyl) (4-hydroxyphenyl) propane.

Specific examples of the diol component (bisphenol, biphenol, etc.) of the polycarbonate resin that can be suitably used are shown below. This illustration is made for the purpose of clarifying the gist of the present invention, and is not limited to the illustrated structure unless it is contrary to the gist of the present invention.

特に好ましくは下記構造であり、バインダー樹脂としては、下記式（２）で表される繰り返し構造を有する。

In order to maximize the effects of the present invention, a diol component having the following structure is more preferable.

Particularly preferred is the following structure, and the binder resin has a repeating structure represented by the following formula (2).

酸成分としては、以下構造を用いることが好ましい。

特に好ましい酸成分は、以下である。また、これらのジカルボン酸成分、ジオール成分を複数種組み合わせて用いることも可能である。

In order to improve mechanical properties, it is preferable to use a polyarylate resin. In this case, it is preferable to use the following structure as a diol component,

As the acid component, the following structure is preferably used.

Particularly preferred acid components are as follows. Moreover, it is also possible to use these dicarboxylic acid components and diol components in combination.

  If the molecular weight of the binder resin is too low, the mechanical strength may be insufficient. Conversely, if the molecular weight is too high, the viscosity of the coating solution for forming the photosensitive layer may be too high and the productivity may be reduced. Therefore, in the case of a polycarbonate resin or a polyarylate resin, the viscosity average molecular weight is 10,000 or more, preferably 20,000 or more, and 100,000 or less, more preferably 70,000 or less.

<Protective layer, other>
A protective layer may be provided on the photosensitive layer for the purpose of preventing electrical and mechanical deterioration. Further, for the purpose of reducing frictional resistance and wear on the surface of the electrophotographic photosensitive member, the surface layer may contain a fluorine-based resin, a silicone resin, etc., or particles containing these resins or inorganic compound particles may be included. Good.

<Method for forming photosensitive layer>
The photosensitive layer of the electrophotographic photoreceptor of the present invention is prepared by dissolving or dispersing the compound represented by the formula (1) in a suitable solvent together with a binder according to a conventional method. Manufactured by applying and drying a coating solution obtained by adding known additives such as infectious agents, electron-withdrawing compounds, other charge transporting substances, or plasticizers, pigments, etc. on a conductive substrate. be able to.

  In the case of a photosensitive layer comprising two layers of a charge generation layer and a charge transport layer, the charge generation layer is formed on the charge transport layer obtained by applying the coating solution on the charge generation layer or by applying the coating solution. Can be produced.

  Examples of the photosensitive layer coating formation method include spray coating, spiral coating, ring coating, and dip coating. Spray coating methods include air spray, airless spray, electrostatic air spray, electrostatic airless spray, rotary atomizing electrostatic spray, hot spray, and hot airless spray. Considering the degree of conversion, adhesion efficiency, etc., in the rotary atomizing electrostatic spray, the conveying method disclosed in the republished Japanese Patent Publication No. 1-805198, that is, the cylindrical workpiece is rotated while the axial direction is spaced. By continuously transporting the electrophotographic photosensitive member, an electrophotographic photosensitive member excellent in film thickness uniformity can be obtained with a comprehensively high adhesion efficiency.

  Examples of the spiral coating method include a method using a liquid injection coating machine or a curtain coating machine disclosed in Japanese Patent Laid-Open No. 52-119651, and paint from a minute opening disclosed in Japanese Patent Laid-Open No. 1-2231966. There are a method of continuously flying in a streak shape, a method using a multi-nozzle body disclosed in JP-A-3-193161, and the like.

  In the case of the dip coating method, in the preparation of the coating solution or dispersion, the total solid concentration is preferably 10% by mass or more in the case of a monolayer type photosensitive layer and the charge transport layer of a laminated type photosensitive layer. 50% by mass or less, more preferably 15% by mass to 35% by mass, and the viscosity is preferably 50 to 700 mPa · s, more preferably 100 to 500 mPa · s. The solid content concentration is preferably 15% by mass or less, more preferably 1 to 10% by mass, and the viscosity is preferably 0.1 to 10 mPa · s.

  After the coating film is formed, the coating film is dried, and the drying temperature time may be adjusted so that necessary and sufficient drying is performed. If the drying temperature is too high, bubbles may be mixed in the photosensitive layer. If the drying temperature is too low, it takes time for drying, and the amount of residual solvent may increase to adversely affect electrical characteristics. ° C, preferably 110-170 ° C, more preferably 120-140 ° C. As a drying method, a hot air dryer, a steam dryer, an infrared dryer, a far infrared dryer, or the like can be used.

<Solvent and dispersion medium used for forming photosensitive layer>
As a solvent or a dispersion medium used for preparing a coating solution for coating and forming each layer constituting the electrophotographic photosensitive member, for example,
Alcohols such as methanol, ethanol, propanol and 2-methoxyethanol; ethers such as tetrahydrofuran, 1,4-dioxane and dimethoxyethane;
Esters such as methyl formate and ethyl acetate;
Ketones such as acetone, methyl ethyl ketone, cyclohexanone;
Aromatic hydrocarbons such as benzene, toluene, xylene;
Chlorinated hydrocarbons such as dichloromethane, chloroform, 1,2-dichloroethane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, tetrachloroethane, 1,2-dichloropropane, trichloroethylene;
nitrogen-containing compounds such as n-butylamine, isopropanolamine, diethylamine, triethanolamine, ethylenediamine, and triethylenediamine;
Examples include aprotic polar solvents such as acetonitrile, N-methylpyrrolidone, N, N-dimethylformamide, and dimethyl sulfoxide, and these are used alone or in combination of two or more.

[toner]
Next, the toner used in the image forming apparatus of the present invention will be described. The toner that is a developer for developing the latent image is preferably a toner having a specific circularity. By using the toner having a specific average circularity as described above, the image forming apparatus of the present invention can form a high-quality image.

<Average circularity of toner>
The preferable toner shape in the present invention is such that the shape of each particle included in the particle group constituting the toner is closer to each other, and the closer to the spherical shape, the less the charge amount is localized in the toner particles. However, if the shape of the toner is too close to a perfect sphere, the toner remains on the surface of the electrophotographic photosensitive member due to poor cleaning of the toner after image formation. In such a case, it is necessary to perform strong cleaning so as not to cause defective cleaning. As a result, the electrophotographic photosensitive member is likely to be worn due to strong cleaning. In some cases, the life of the electrophotographic photosensitive member may be shortened due to a tendency to become damaged. In addition, it is difficult to produce a perfect spherical toner, and the cost of the toner increases, so that the industrial utility value is low.

  Therefore, specifically, the average circularity measured by the flow type particle image analyzer is usually 0.940 or more, preferably 0.950 or more, more preferably 0.960 or more. The upper limit of the average circularity is not limited as long as it is 1.000 or less, but is preferably 0.995 or less, more preferably 0.990 or less.

The average circularity in the present invention is used as a simple method for quantitatively expressing the shape of toner particles. In the present invention, the average circularity is measured using a flow type particle image analyzer FPIA-2000 manufactured by Sysmex Corporation. And the circularity [a] of the measured particle is obtained by the following equation (A).
Circularity a = L ₀ / L (A)
[In Formula (A), L ₀ represents the perimeter of a circle having the same projected area as the particle image, and L represents the perimeter of the particle image when image processing is performed. ]

  The average circularity is an index of the degree of unevenness of the toner particles, and indicates 1.00 when the toner is a perfect sphere, and the circularity becomes smaller as the surface shape becomes more complicated.

  A specific method for measuring the average circularity is as follows. That is, a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 20 mL of water from which impurities in the container have been removed in advance, and about 0.05 g of a measurement sample (toner) is further added. The suspension in which the sample is dispersed is irradiated with ultrasonic waves for 30 seconds, and the dispersion concentration is set to 3.0 to 8.0 thousand pieces / μL (micro L). The circularity distribution of particles having an equivalent circle diameter of 60 μm or more and less than 160 μm is measured.

<Toner type>
Various types of toner are usually obtained depending on the production method, but any toner may be used in the present invention.

  Hereinafter, the toner manufacturing method and the type of toner will be described. The toner may be produced by any conventionally known method, for example, a toner produced by a polymerization method, a melt suspension method, or the like. Furthermore, a so-called pulverized toner is formed into a spherical shape by a treatment such as heat. However, a toner produced by a so-called polymerization method that generates toner particles in an aqueous medium is preferable.

  Examples of the polymerization toner include suspension polymerization toner and emulsion polymerization aggregation toner. In particular, the emulsion polymerization aggregation method is a method for producing a toner by aggregating polymer resin fine particles and a coloring agent in a liquid medium, and adjusting the particle size and circularity of the toner by controlling the aggregation conditions. Is preferable.

  In order to improve the releasability, low-temperature fixability, high-temperature offset property, filming resistance and the like of the toner, a method of incorporating a low softening point substance (for example, wax) into the toner has been proposed. In the melt-kneading pulverization method, it is difficult to increase the amount of wax contained in the toner, and the limit is about 5% by mass with respect to the polymer (binder resin). In contrast, the polymerized toner can contain a low softening point substance in a large amount (5 to 30% by mass). The polymer here is one of the materials constituting the toner. For example, in the case of a toner manufactured by an emulsion polymerization aggregation method described later, the polymer is obtained by polymerizing a polymerizable monomer.

  Hereinafter, the toner produced by the emulsion polymerization aggregation method will be described in more detail. When a toner is produced by an emulsion polymerization aggregation method, the production process usually includes a polymerization process, a mixing process, an aggregation process, a fusion process, and a washing / drying process. That is, polymer primary particles are generally obtained by emulsion polymerization (polymerization step), and if necessary, a colorant (pigment), wax, charge control agent, etc. are dispersed in a dispersion containing the polymer primary particles. The body is mixed (mixing step), and a flocculant is added to the dispersion to agglomerate the primary particles to form particle aggregates (aggregation step). Thus, particles are obtained (fusion process), and the obtained particles are washed and dried (washing / drying process) to obtain mother particles.

(Polymerization process)
The polymer fine particles (polymer primary particles) are not particularly limited. Therefore, either a fine particle obtained by polymerizing a polymerizable monomer in a liquid medium by a suspension polymerization method, an emulsion polymerization method, or the like, or a fine particle obtained by pulverizing a lump of a polymer such as a resin is a polymer. It may be used as primary particles. However, a polymerization method, particularly an emulsion polymerization method, in particular, a method using wax as a seed in emulsion polymerization is preferable. When wax is used as a seed in emulsion polymerization, fine particles having a structure in which the polymer wraps the wax can be produced as polymer primary particles. According to this method, the wax can be contained in the toner without being exposed on the surface of the toner. For this reason, there is no contamination of the apparatus member by the wax, the chargeability of the toner is not impaired, and the low temperature fixing property, high temperature offset property, filming resistance, releasability, etc. of the toner can be improved. it can.

  Hereinafter, a description will be given of a method of performing emulsion polymerization using wax as a seed, thereby obtaining polymer primary particles. The emulsion polymerization method may be performed according to a conventionally known method. Usually, a wax is dispersed in a liquid medium in the presence of an emulsifier to form wax fine particles. A polymerization initiator, a polymerizable monomer that gives a polymer by polymerization, that is, a polymerizable carbon-carbon double bond. Polymerization is carried out by mixing and stirring the compound having, and if necessary, a chain transfer agent, a pH adjuster, a polymerization degree adjuster, an antifoaming agent, a protective colloid, an internal additive and the like. As a result, an emulsion in which polymer fine particles (that is, polymer primary particles) having a structure in which the polymer wraps the wax is dispersed in the liquid medium is obtained. Examples of the structure in which the polymer wraps the wax include a core-shell type, a phase separation type, and an occlusion type, and the core-shell type is preferable.

(I. Wax)
As the wax, any known wax that can be used for this purpose can be used. For example, olefin waxes such as low molecular weight polyethylene, low molecular weight polypropylene and copolymer polyethylene; paraffin wax; silicone wax having an alkyl group; fluororesin wax such as low molecular weight polytetrafluoroethylene; higher fatty acids such as stearic acid; eicosanol Long-chain aliphatic alcohols such as behenate behenate, montanic acid ester, stearic acid ester ester wax having a long-chain aliphatic group; distearyl ketone and other long-chain alkyl group ketones; hydrogenated castor oil, Plant waxes such as carnauba wax; esters or partial esters obtained from polyhydric alcohols such as glycerin and pentaerythritol and long chain fatty acids; higher fatty acid amides such as oleic acid amide and stearic acid amide; low molecular weight poly Ester, and the like. Especially, what has at least 1 the endothermic peak by a differential thermal analysis (DSC) in 50-100 degreeC is preferable.

  Among the waxes, for example, ester waxes, paraffin waxes, olefin waxes such as low molecular weight polypropylene and copolymer polyethylene, silicone waxes, and the like are preferable because a release effect can be obtained in a small amount. Paraffin wax is particularly preferable. In addition, 1 type may be used for wax and it may use 2 or more types together by arbitrary combinations and a ratio.

  When using wax, the amount used is arbitrary. However, the wax is usually 3 parts by mass or more, preferably 5 parts by mass or more, and usually 40 parts by mass or less, preferably 30 parts by mass or less with respect to 100 parts by mass of the polymer. If the amount of the wax is too small, the fixing temperature range may be insufficient. If the amount is too large, the apparatus member may be contaminated and the image quality may be deteriorated.

(Ii. Emulsifier)
There is no restriction | limiting in an emulsifier, Arbitrary things can be used in the range which does not impair the effect of this invention remarkably. For example, any of nonionic, anionic, cationic and amphoteric surfactants can be used.

  Examples of the nonionic surfactant include polyoxyalkylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyalkylene alkyl phenyl ethers such as polyoxyethylene octylphenyl ether, and sorbitan fatty acid esters such as sorbitan monolaurate. And the like.

  Examples of the anionic surfactant include fatty acid salts such as sodium stearate and sodium oleate, alkylaryl sulfonates such as sodium dodecylbenzene sulfonate, and alkyl sulfate salts such as sodium lauryl sulfate. . Furthermore, examples of the cationic surfactant include alkylamine salts such as laurylamine acetate, and quaternary ammonium salts such as lauryltrimethylammonium chloride. Examples of amphoteric surfactants include alkylbetaines such as lauryl betaine. Among these, nonionic surfactants and anionic surfactants are preferable. In addition, 1 type may be used for an emulsifier and it may use 2 or more types together by arbitrary combinations and a ratio.

  Furthermore, the amount of the emulsifier is arbitrary as long as the effects of the present invention are not significantly impaired, but the emulsifier is usually used at a ratio of 1 to 10 parts by mass with respect to 100 parts by mass of the polymerizable monomer.

(Iii. Liquid medium)
As the liquid medium, an aqueous medium is usually used, and water is particularly preferably used. However, the quality of the liquid medium is also related to the coarsening due to reaggregation of particles in the liquid medium. When the conductivity of the liquid medium is high, the dispersion stability with time tends to deteriorate. Therefore, when an aqueous medium such as water is used as the liquid medium, it is preferable to use ion-exchanged water or distilled water that has been desalted so that the electrical conductivity is usually 10 μS / cm or less, preferably 5 μS / cm or less. preferable. The conductivity is measured at 25 ° C. using a conductivity meter (personal SC meter model SC72 and detector SC72SN-11 manufactured by Yokogawa Electric Corporation). Moreover, there is no restriction | limiting in the usage-amount of a liquid medium, However, The quantity of about 1-20 mass times is normally used with respect to a polymerizable monomer.

  By dispersing the wax in the liquid medium in the presence of an emulsifier, fine wax particles are obtained. The order of blending the emulsifier and the wax in the liquid medium is arbitrary, but usually the emulsifier is first blended in the liquid medium and then the wax is mixed. Moreover, you may mix | blend an emulsifier with a liquid medium continuously.

(Iv. Polymerization initiator)
After preparing the wax fine particles, a polymerization initiator is blended in the liquid medium. Any polymerization initiator can be used as long as the effects of the present invention are not significantly impaired. For example, persulfates such as sodium persulfate and ammonium persulfate; organic peroxides such as t-butyl hydroperoxide, cumene hydroperoxide and p-menthane hydroperoxide; inorganics such as hydrogen peroxide Examples thereof include peroxides. Of these, inorganic peroxides are preferable. In addition, 1 type may be used for a polymerization initiator and it may use 2 or more types together by arbitrary combinations and a ratio.

  Further, other examples of the polymerization initiator include persulfates, organic or inorganic peroxides, and reducing organic compounds such as ascorbic acid, tartaric acid, citric acid, sodium thiosulfate, sodium bisulfite, metabisulfate. A redox initiator can also be used in combination with reducing inorganic compounds such as sodium sulfite. In this case, reducing inorganic compounds may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios. Moreover, there is no restriction | limiting in the usage-amount of a polymerization initiator, It is arbitrary. However, a polymerization initiator is normally used in the ratio of 0.05-2 mass parts with respect to 100 mass parts of polymerizable monomers.

(V. Polymerizable monomer)
After the wax fine particles are prepared, a polymerizable monomer is blended in the liquid medium in addition to the polymerization initiator. There is no particular limitation on the polymerizable monomer, but for example, styrenes, (meth) acrylic acid esters, acrylamides, monomers having Bronsted acidic groups (hereinafter simply referred to as “acidic monomers”) ), A monofunctional monomer such as a monomer having a Bronsted basic group (hereinafter sometimes simply referred to as “basic monomer”). Further, a monofunctional monomer can be used in combination with a polyfunctional monomer.

  Examples of styrenes include styrene, methyl styrene, chlorostyrene, dichlorostyrene, p-tert-butyl styrene, pn-butyl styrene, pn-nonyl styrene, and the like. Examples of the (meth) acrylic acid ester include methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, hydroxyethyl acrylate, 2-ethylhexyl acrylate, and methyl methacrylate. , Ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, hydroxyethyl methacrylate, and 2-ethylhexyl methacrylate. Examples of acrylamides include acrylamide, N-propyl acrylamide, N, N-dimethyl acrylamide, N, N-dipropyl acrylamide, N, N-dibutyl acrylamide, and the like.

  Furthermore, examples of the acidic monomer include monomers having a carboxyl group such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, and cinnamic acid; monomers having a sulfonic acid group such as sulfonated styrene; vinylbenzenesulfonamide and the like. Examples thereof include a monomer having a sulfonamide group. Examples of the basic monomer include aromatic vinyl compounds having an amino group such as aminostyrene, nitrogen-containing heterocycle-containing monomers such as vinylpyridine and vinylpyrrolidone; amino groups such as dimethylaminoethyl acrylate and diethylaminoethyl methacrylate. Examples include (meth) acrylic acid esters. In addition, the acidic monomer and the basic monomer may exist as a salt with a counter ion.

  Furthermore, as the polyfunctional monomer, for example, divinylbenzene, hexanediol diacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, neopentyl glycol diacrylate, Examples include diallyl phthalate. It is also possible to use a monomer having a reactive group such as glycidyl methacrylate, N-methylolacrylamide, or acrolein. Among these, radically polymerizable bifunctional monomers, particularly divinylbenzene and hexanediol diacrylate are preferable.

  Among these, the polymerizable monomer is preferably composed of at least styrenes, (meth) acrylic acid esters, and acidic monomers having a carboxyl group. In particular, styrene is preferred as the styrene, butyl acrylate is preferred as the (meth) acrylic acid ester, and acrylic acid is preferred as the acidic monomer having a carboxyl group. In addition, 1 type may be used for a polymerizable monomer and it may use 2 or more types together by arbitrary combinations and a ratio.

  When emulsion polymerization is performed using wax as a seed, it is preferable to use an acidic monomer or a basic monomer and a monomer other than these in combination. This is because the dispersion stability of the polymer primary particles can be improved by using an acidic monomer or a basic monomer in combination.

  At this time, the compounding amount of the acidic monomer or basic monomer is arbitrary, but the amount of the acidic monomer or basic monomer used is usually 0.05 parts by mass or more, preferably 0 with respect to 100 parts by mass of the total polymerizable monomer. It is desirable that the amount be 5 parts by mass or more, more preferably 1 part by mass or more, and usually 10 parts by mass or less, preferably 5 parts by mass or less. When the blending amount of the acidic monomer or basic monomer is less than the above range, the dispersion stability of the polymer primary particles may be deteriorated, and when it exceeds the upper limit, the chargeability of the toner may be adversely affected.

  Moreover, when using a polyfunctional monomer together, the compounding quantity is arbitrary, However, The compounding quantity of the polyfunctional monomer with respect to 100 mass parts of polymerizable monomers is 0.005 mass part or more normally, Preferably it is 0.00. 1 part by mass or more, more preferably 0.3 part by mass or more, and usually 5 parts by mass or less, preferably 3 parts by mass or less, more preferably 1 part by mass or less. By using a polyfunctional monomer, the fixability of the toner can be improved. At this time, if the blending amount of the polyfunctional monomer is less than the above range, the high temperature offset resistance may be inferior, and if it exceeds the upper limit, the low temperature fixability may be inferior.

  The method for blending the polymerizable monomer into the liquid medium is not particularly limited. For example, any of batch addition, continuous addition, and intermittent addition may be used, but it is preferable to blend continuously from the viewpoint of reaction control. Moreover, when using several polymerizable monomer together, each polymerizable monomer may be mix | blended separately, and may be mix | blended after mixing beforehand. Furthermore, you may mix | blend, changing the composition of a monomer mixture.

(Vi. Chain transfer agent, etc.)
After preparing the above wax fine particles, the liquid medium includes, in addition to the polymerization initiator and the polymerizable monomer, a chain transfer agent, a pH adjuster, a polymerization degree adjuster, and an antifoaming agent as necessary. Additives such as protective colloids and internal additives. Any of these additives can be used as long as the effects of the present invention are not significantly impaired. Moreover, these additives may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

  Any known chain transfer agent can be used. Specific examples include t-dodecyl mercaptan, 2-mercaptoethanol, diisopropylxanthogen, carbon tetrachloride, trichlorobromomethane and the like. Moreover, a chain transfer agent is normally used in the ratio of 5 mass parts or less with respect to 100 mass parts of polymerizable monomers.

  Further, as the protective colloid, any known colloid that can be used for this purpose can be used. Specific examples include partially or completely saponified polyvinyl alcohols such as polyvinyl alcohol, and cellulose derivatives such as hydroxyethyl cellulose.

  Examples of the internal additive include those for modifying the adhesiveness, cohesiveness, fluidity, chargeability, surface resistance and the like of toners such as silicone oil, silicone varnish, and fluorine oil.

(Vii. Polymer primary particles)
Polymer primary particles are obtained by mixing a polymerization initiator, a polymerizable monomer, and, if necessary, an additive in a liquid medium containing wax fine particles, stirring, and polymerizing. The polymer primary particles can be obtained in the form of an emulsion in a liquid medium.

  There is no restriction | limiting in the order which mixes a polymerization initiator, a polymerizable monomer, an additive, etc. with a liquid medium. Further, the mixing and stirring methods are not limited and are arbitrary. Furthermore, the reaction temperature of the polymerization (emulsion polymerization reaction) is arbitrary as long as the reaction proceeds. However, the polymerization temperature is usually 50 ° C. or higher, preferably 60 ° C. or higher, more preferably 70 ° C. or higher, and usually 120 ° C. or lower, preferably 100 ° C. or lower, more preferably 90 ° C. or lower.

  The volume average particle diameter of the polymer primary particles is not particularly limited, but is usually 0.02 μm or more, preferably 0.05 μm or more, more preferably 0.1 μm or more, and usually 3 μm or less, preferably 2 μm or less, more preferably Is 1 μm or less. If the volume average particle size is too small, it may be difficult to control the aggregation rate, and if the volume average particle size is too large, the particle size of the toner obtained by aggregation tends to be large. It may be difficult to obtain a toner having a diameter. The volume average particle diameter is measured with a particle size analyzer using a dynamic light scattering method described later.

In the present invention, the volume particle size distribution is measured by a dynamic light scattering method. This method obtains the particle size distribution by detecting the speed of Brownian motion of finely dispersed particles, irradiating the particles with laser light, and detecting light scattering (Doppler shift) with different phases according to the speed. It is. In the actual measurement, for the above volume particle size, an ultrafine particle size distribution measuring device using a dynamic light scattering method (manufactured by Nikkiso Co., Ltd., UPA-EX150, hereinafter sometimes abbreviated as “UPA-EX”) is used. Use the following settings.
Measurement upper limit: 6.54 μm
Measurement lower limit: 0.0008 μm
Number of channels: 52
Measurement time: 100 sec.
Measurement temperature: 25 ° C
Particle permeability: Absorption Particle refractive index: N / A (not applicable)
Particle shape: non-spherical density: 1 g / cm ³
Dispersion medium type: WATER
Dispersion medium refractive index: 1.333
At the time of measurement, measurement is performed with a sample in which a dispersion of particles is diluted with a liquid medium so that the sample concentration index is in the range of 0.01 to 0.1 and is dispersed with an ultrasonic cleaner. And the volume average particle diameter in this invention is defined as an arithmetic mean value as a result of said volume particle size distribution.

  The polymer constituting the polymer primary particles has at least one of peak molecular weights in gel permeation chromatography, usually 3000 or more, preferably 10,000 or more, more preferably 30,000 or more, and usually 100,000 or less. , Preferably 70,000 or less, more preferably 60,000 or less. When the peak molecular weight is in the above range, the durability, storage stability, and fixability of the toner tend to be good. Here, as the peak molecular weight, a value converted to polystyrene is used, and components insoluble in a solvent are excluded in measurement. The peak molecular weight can be measured in the same manner as the toner described later.

  In particular, when the polymer is a styrene resin, the lower limit of the number average molecular weight of the polymer in gel permeation chromatography is usually 2000 or more, preferably 2500 or more, more preferably 3000 or more, and the upper limit is Usually, it is 50,000 or less, preferably 40,000 or less, more preferably 35,000 or less. Furthermore, the lower limit of the weight average molecular weight of the polymer is usually 20,000 or more, preferably 30,000 or more, more preferably 50,000 or more, and the upper limit is usually 1,000,000 or less, preferably 500,000 or less. When a styrene resin in which at least one of the number average molecular weight and the weight average molecular weight, preferably both falls within the above ranges, is used as the polymer, the resulting toner has good durability, storage stability and fixability. is there. Further, the molecular weight distribution may have two main peaks. In addition, styrene resin refers to what styrene occupies normally 50 mass% or more in the whole polymer, Preferably 65 mass% or more is occupied.

  Further, the softening point of the polymer (hereinafter sometimes abbreviated as “Sp”) is usually 150 ° C. or less, preferably 140 ° C. or less from the viewpoint of low energy fixing, and usually 80 ° C. or more. Preferably it is 100 degreeC or more from the point of high temperature offset resistance and durability. Here, the softening point of the polymer is determined by measuring 1.0 g of a sample with a nozzle 1 mm × 10 mm, a load of 30 kg, a preheating time of 50 ° C. for 5 minutes, and a temperature rising rate of 3 ° C./min in a flow tester. The temperature at the midpoint of the strand from the start to the end of the flow can be obtained.

  Furthermore, the glass transition temperature (Tg) of the polymer is usually 80 ° C. or lower, preferably 70 ° C. or lower. If the glass transition temperature (Tg) of the polymer is too high, low energy fixing may not be possible. Moreover, the minimum of the glass transition temperature (Tg) of a polymer is 40 degreeC or more normally, Preferably it is 50 degreeC or more. If the glass transition temperature (Tg) of the polymer is too low, the blocking resistance may decrease. Here, the glass transition temperature (Tg) of the polymer is the intersection of two tangent lines by drawing a tangent line at the beginning of the transition (inflection) of the curve measured at a temperature rising rate of 10 ° C./min in a differential scanning calorimeter. Temperature. The softening point and glass transition temperature (Tg) of the polymer can be adjusted to the above ranges by adjusting the polymer type, monomer composition ratio, molecular weight, and the like.

(Mixing process and aggregation process)
By mixing and aggregating pigment particles in the emulsion in which the polymer primary particles are dispersed, an emulsion of aggregates (aggregated particles) containing a polymer and a pigment is obtained. In this case, it is preferable to prepare a pigment particle dispersion in which the pigment is uniformly dispersed in advance in a liquid medium using a surfactant or the like, and mix this with an emulsion of polymer primary particles. At this time, an aqueous solvent such as water is usually used as the liquid medium of the pigment particle dispersion, and the pigment particle dispersion is prepared as an aqueous dispersion. At that time, if necessary, a wax, a charge control agent, a release agent, an internal additive and the like may be mixed into the emulsion. Moreover, in order to maintain the stability of the pigment particle dispersion, the above-described emulsifier may be added.

  As the polymer primary particles, the polymer primary particles obtained by emulsion polymerization can be used. Under the present circumstances, 1 type may be used for a polymer primary particle, and 2 or more types may be used together by arbitrary combinations and a ratio. Furthermore, polymer primary particles (hereinafter, may be abbreviated as “combined polymer particles”) produced using raw materials and reaction conditions different from those of the emulsion polymerization described above may be used in combination.

  Examples of the combined polymer particles include fine particles obtained by suspension polymerization or pulverization. Resin can be used as the material for such combined polymer particles. As this resin, for example, vinyl acetate, vinyl chloride, vinyl, in addition to the monomer (co) polymer used for the emulsion polymerization described above. Thermoplastics such as homopolymers or copolymers of vinyl monomers such as alcohol, vinyl butyral, vinyl pyrrolidone, saturated polyester resins, polycarbonate resins, polyamide resins, polyolefin resins, polyarylate resins, polysulfone resins, polyphenylene ether resins, etc. Examples thereof include thermosetting resins such as resins and unsaturated polyester resins, phenol resins, epoxy resins, urethane resins, and rosin-modified maleic resins. These combined polymer particles may be used alone or in combination of two or more in any combination and ratio. However, the ratio of the combination polymer particles is usually 5% by mass or less, preferably 4% by mass or less, more preferably 3% by mass or less, based on the total of the polymer primary particles and the polymer of the combination polymer particles. .

Moreover, there is no restriction | limiting in a pigment, According to the use, arbitrary things can be used. However, although the pigment is usually present in the form of particles as colorant particles, it is preferable that the pigment particles have a smaller density difference from the polymer primary particles in the emulsion polymerization aggregation method. This is because when the density difference is smaller, a uniform aggregated state is obtained when the polymer temporary particles and the pigment are aggregated, and thus the performance of the obtained toner is improved. The density of the polymer primary particles is usually 1.1 to 1.3 g / cm ³ .

From the above viewpoint, the true density of the pigment particles measured by the pycnometer method specified in JIS K 5101-11-1: 2004 is usually 1.2 g / cm ³ or more, preferably 1.3 g / cm ³ or more. Also, it is usually less than 2.0 g / cm ³ , preferably 1.9 g / cm ³ or less, more preferably 1.8 g / cm ³ or less. When the true density of the pigment is large, the sedimentation property in a liquid medium may be deteriorated. In addition, in consideration of problems such as storage stability and sublimation, the pigment is preferably carbon black or an organic pigment.

  Examples of pigments that satisfy the above conditions include yellow pigments, magenta pigments, and cyan pigments shown below. Further, as the black pigment, carbon black or a mixture of the following yellow pigment / magenta pigment / cyan pigment mixed with black is used.

  Among these, carbon black used as a black pigment exists as an aggregate of very fine primary particles, and when dispersed as a pigment particle dispersion, the carbon black particles are likely to become coarse due to reaggregation. . The degree of reagglomeration of carbon black particles is correlated with the amount of impurities contained in carbon black (the degree of residual undecomposed organic matter), and if there are many impurities, coarsening due to reaggregation after dispersion is significant. Show the trend.

  For quantitative evaluation of the amount of impurities, the ultraviolet absorbance of the toluene extract of carbon black measured by the following measurement method is usually 0.05 or less, preferably 0.03 or less. In general, since carbon black of the channel method tends to have a large amount of impurities, the carbon black used for the toner in the present invention is preferably manufactured by the furnace method.

  The ultraviolet absorbance (λc) of carbon black is determined by the following method. That is, first, 3 g of carbon black was sufficiently dispersed and mixed in 30 mL of toluene. Filter using 5C filter paper. Thereafter, the filtrate was put in a quartz cell having a 1 cm square light absorption part, and the value (λs) measured for absorbance at a wavelength of 336 nm using a commercially available ultraviolet spectrophotometer, and the value obtained by measuring the absorbance of toluene alone as a reference using the same method. From (λo), the ultraviolet absorbance is obtained by λc = λs−λo. Examples of commercially available spectrophotometers include an ultraviolet-visible spectrophotometer (UV-3100PC) manufactured by Shimadzu Corporation.

  Examples of yellow pigments include compounds typified by condensed azo compounds and isoindolinone compounds. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 168, 180, 185 and the like are preferable.

  Furthermore, examples of the magenta pigment include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. Specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 207, 209, 220, 221, 238, 254, C.I. I. Pigment Violet 19 and the like are preferable. Among them, C.I. I. Pigment red 122, 202, 207, 209, C.I. I. A quinacridone pigment represented by pigment violet 19 is more preferred. This quinacridone pigment is suitable as a magenta pigment because of its clear hue and high light resistance. Among the quinacridone pigments, C.I. I. A compound represented by CI Pigment Red 122 is particularly preferable.

  Examples of cyan pigments include copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds, and the like. Specifically, C.I. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66 and the like are preferable. In addition, 1 type may be used for a pigment and it may use 2 or more types together by arbitrary combinations and a ratio.

  The above-mentioned pigment is dispersed in a liquid medium and mixed with an emulsion containing polymer primary particles after forming a pigment particle dispersion. Under the present circumstances, the usage-amount of the pigment particle in a pigment particle dispersion is 3 mass parts or more normally with respect to 100 mass parts of liquid media, Preferably it is 5 mass parts or more, Moreover, normally 50 mass parts or less, Preferably it is 40 masses. Or less. When the blending amount of the colorant exceeds the above range, the pigment concentration is high and the pigment particles may reaggregate in the dispersion. When the blending amount is less than the above range, the dispersion becomes excessive and an appropriate particle size distribution is obtained. It can be difficult.

  Further, the ratio of the amount of the pigment used relative to the polymer contained in the polymer primary particles is usually 1% by mass or more, preferably 3% by mass or more, and usually 20% by mass or less, preferably 15% by mass or less. If the amount of the pigment used is too small, the image density may become thin, and if it is too large, the aggregation control may be difficult.

  Further, the pigment particle dispersion may contain a surfactant. Although there is no restriction | limiting in particular in this surfactant, For example, the thing similar to the surfactant illustrated as an emulsifier in description of an emulsion polymerization method is mentioned. Of these, nonionic surfactants, anionic surfactants such as alkylaryl sulfonates such as sodium dodecylbenzenesulfonate, and polymer surfactants are preferred. Moreover, 1 type of surfactant may be used in this case, and 2 or more types may be used together by arbitrary combinations and a ratio.

  In addition, the ratio of the pigment to a pigment particle dispersion is 10-50 mass% normally. Further, as the liquid medium of the pigment particle dispersion, an aqueous medium is usually used, and preferably water. At this time, the water quality of the polymer primary particles and the pigment particle dispersion is also related to the coarsening due to re-aggregation of each particle. If the electrical conductivity is high, the dispersion stability with time may deteriorate. Therefore, it is preferable to use ion-exchanged water or distilled water that has been desalted so that the electrical conductivity is usually 10 μS / cm or less, preferably 5 μS / cm or less. The conductivity is measured at 25 ° C. using a conductivity meter (personal SC meter model SC72 and detector SC72SN-11 manufactured by Yokogawa Electric Corporation).

  Further, when the pigment is mixed with the emulsion containing the polymer primary particles, a wax may be mixed with the emulsion. As the wax, the same waxes described in the explanation of the emulsion polymerization method can be used. The wax may be mixed before, during or after mixing the pigment with the emulsion containing the polymer primary particles.

  Moreover, when mixing a pigment with the emulsion containing a polymer primary particle, you may mix a charge control agent with an emulsion. As the charge control agent, any known charge control agent can be used. Examples of the positively chargeable charge control agent include nigrosine dyes, quaternary ammonium salts, triphenylmethane compounds, imidazole compounds, polyamine resins, and the like. Examples of negative charge control agents include azo complex compound dyes containing atoms such as Cr, Co, Al, Fe, and B; metal salts or metal complexes of salicylic acid or alkylsalicylic acid; curixarene compounds, benzyl Examples include acid metal salts or metal complexes, amide compounds, phenolic compounds, naphthol compounds, and phenolamide compounds. Among these, colorless or light-colored ones are preferable in order to avoid color tone troubles as toners, and quaternary ammonium salts and imidazole compounds are particularly preferable as positively chargeable charge control agents, and Cr, Alkyl salicylic acid complex compounds and curixarene compounds containing atoms such as Co, Al, Fe, and B are preferred. In addition, 1 type may be used for a charge control agent and it may use 2 or more types together by arbitrary combinations and a ratio.

  Although there is no restriction | limiting in the usage-amount of a charge control agent, 0.01 mass part or more normally with respect to 100 mass parts of polymers, Preferably it is 0.1 mass part or more, Moreover, 10 mass parts or less, Preferably it is 5 mass parts or less. It is. If the amount of the charge control agent used is too small or too large, the desired charge amount may not be obtained.

  The charge control agent may be mixed before, during or after mixing the pigment with the emulsion containing the polymer primary particles. Further, like the pigment particles, the charge control agent is preferably mixed at the time of aggregation in a state emulsified in a liquid medium (usually an aqueous medium).

  After the pigment is mixed in the emulsion containing the polymer primary particles, the polymer primary particles and the pigment are aggregated. As described above, at the time of mixing, the pigment is usually mixed in the state of a pigment particle dispersion. The aggregation method is not limited and is arbitrary, and examples thereof include heating, electrolyte mixing, pH adjustment, and the like. Especially, the method of mixing electrolyte is preferable.

Examples of the electrolyte when the agglomeration is performed by mixing the electrolyte include chlorides such as NaCl, KCl, LiCl, MgCl ₂ , CaCl ₂ ; Na ₂ SO ₄ , K ₂ SO ₄ , Li ₂ SO ₄ , MgSO ₄ , Inorganic salts such as sulfates such as CaSO ₄ , ZnSO ₄ , Al ₂ (SO ₄ ) ₃ , Fe ₂ (SO ₄ ) ₃ ; organic salts such as CH ₃ COONa and C ₆ H ₅ SO ₃ Na. Of these, inorganic salts having a divalent or higher polyvalent metal cation are preferred. In addition, 1 type may be used for electrolyte and 2 or more types may be used together by arbitrary combinations and a ratio.

  The amount of electrolyte used varies depending on the type of electrolyte, but is usually 0.05 parts by mass or more, preferably 0.1 parts by mass or more, and usually 25 parts by mass or less, based on 100 parts by mass of the solid component in the emulsion. Preferably it is 15 mass parts or less, More preferably, it is 10 mass parts or less. When agglomeration is performed by mixing electrolytes, if the amount of electrolyte used is too small, the agglomeration reaction proceeds slowly and fine powder of 1 μm or less remains after the agglomeration reaction, and the average particle size of the obtained agglomerates is the desired particle size. If the amount of electrolyte used is too large, the agglomeration reaction will occur rapidly, making it difficult to control the particle size. May be included.

  The obtained agglomerates are preferably subsequently spheroidized by heating in a liquid medium, similarly to the secondary agglomerates (agglomerates that have undergone the melting step) described later. Heating may be performed under the same conditions as in the case of the secondary aggregate (same conditions as described in the description of the fusion process).

  On the other hand, when the aggregation is performed by heating, the temperature condition is arbitrary as long as the aggregation proceeds. Specific temperature conditions are usually 15 ° C. or higher, preferably 20 ° C. or higher, and aggregation is performed under a temperature condition of polymer primary particle polymer glass transition temperature (Tg) or lower, preferably 55 ° C. or lower. . Although the time for agglomeration is arbitrary, it is usually 10 minutes or longer, preferably 60 minutes or longer, and usually 300 minutes or shorter, preferably 180 minutes or shorter. In addition, stirring is preferably performed when the aggregation is performed. Although the apparatus used for stirring is not specifically limited, What has a double helical blade is preferable.

  The obtained agglomerates may proceed directly to the next step of forming a resin coating layer (encapsulation step), or may proceed to the encapsulation step after subsequent fusion treatment by heating in a liquid medium. . Desirably, after the aggregation step, the encapsulation step is performed, and the fusion step is performed by heating at a temperature equal to or higher than the glass transition temperature (Tg) of the encapsulated resin fine particles. It is preferable because it does not cause deterioration (thermal deterioration, etc.).

(Encapsulation process)
After obtaining the aggregate, it is preferable to form a resin coating layer on the aggregate as necessary. The encapsulation process for forming a resin coating layer on the aggregate is a process for coating the aggregate with a resin by forming a resin coating layer on the surface of the aggregate. Thereby, the manufactured toner is provided with the resin coating layer. In the encapsulation process, the entire toner may not be completely covered, but the pigment makes it possible to obtain a toner that is not substantially exposed on the surface of the toner particles. Although there is no restriction | limiting in the thickness of the resin coating layer in this case, Usually, it is the range of 0.01-0.5 micrometer.

  The method for forming the resin coating layer is not particularly limited, and examples thereof include a spray drying method, a mechanical particle composite method, an in-situ polymerization method, and a submerged particle coating method. As a method for forming the resin coating layer by the spray drying method, for example, an aggregate forming an inner layer and resin fine particles forming a resin coating layer are dispersed in an aqueous medium to prepare a dispersion, A resin coating layer can be formed on the surface of the aggregate by spraying and drying.

  In addition, as a method for forming a resin coating layer by the mechanical particle composite method, for example, an aggregate that forms an inner layer and resin fine particles that form a resin coating layer are dispersed in a gas phase and mechanically formed in a narrow gap. In this method, resin fine particles are formed into a film on the surface of the aggregate by applying a strong force. For example, a device such as a hybridization system (manufactured by Nara Machinery Co., Ltd.), a mechanofusion system (manufactured by Hosokawa Micron Corporation), or the like can be used.

  Further, as the in-situ polymerization method, for example, an aggregate is dispersed in water, a monomer and a polymerization initiator are mixed, adsorbed on the surface of the aggregate, and heated to polymerize the monomer. Thus, a resin coating layer is formed on the surface of the aggregate that is the inner layer.

  The submerged particle coating method includes, for example, reacting or bonding an aggregate forming an inner layer and resin fine particles forming an outer layer in an aqueous medium to form a resin coating layer on the surface of the aggregate forming the inner layer. Is a method of forming

  The resin fine particles used for forming the outer layer are particles mainly having a resin component smaller than the aggregate. The resin fine particles are not particularly limited as long as they are particles composed of a polymer. However, from the viewpoint that the thickness of the outer layer can be controlled, it is preferable to use resin fine particles similar to the polymer primary particles, the aggregates, or the fused particles obtained by fusing the aggregates. Resin fine particles similar to these polymer primary particles can be produced in the same manner as the polymer primary particles in the aggregate used for the inner layer.

  The amount of the resin fine particles used is arbitrary, but is usually 1% by mass or more, preferably 5% by mass or more, and usually 50% by mass or less, preferably 25% by mass or less with respect to the whole toner particles. . Furthermore, in order to effectively fix or fuse the resin fine particles to the aggregate, the particle size of the resin fine particles is usually preferably about 0.04 to 1 μm.

  The glass transition temperature (Tg) of the polymer component (resin component) used for the resin coating layer is usually 60 ° C. or higher, preferably 70 ° C. or higher, and usually 110 ° C. or lower. Furthermore, the glass transition temperature (Tg) of the polymer component used for the resin coating layer is preferably higher by 5 ° C. or higher than the glass transition temperature (Tg) of the polymer primary particles, and is higher by 10 ° C. or higher. More preferably. If the glass transition temperature (Tg) is too low, storage in a general environment may be difficult, and if it is too high, sufficient meltability may not be obtained.

  Furthermore, it is preferable to contain polysiloxane wax in the resin coating layer. Thereby, the advantage of improvement in high temperature offset resistance can be obtained. Examples of the polysiloxane wax include silicone wax having an alkyl group.

  The content of the polysiloxane wax is not limited, but is usually 0.01% by mass or more, preferably 0.05% by mass or more, more preferably 0.08% by mass or more, and usually 2% with respect to the total toner particles. It is at most mass%, preferably at most 1 mass%, more preferably at most 0.5 mass%. If the amount of the polysiloxane wax in the resin coating layer is too small, the high temperature offset resistance may be insufficient, and if it is too large, the blocking resistance may decrease.

  The method for containing the polysiloxane wax in the resin coating phase is arbitrary. For example, emulsion polymerization is performed using the polysiloxane wax as a seed, and the obtained resin fine particles and the aggregates forming the inner layer are mixed in an aqueous medium. And a resin coating layer containing polysiloxane wax on the surface of the agglomerate forming the inner layer.

(Fusion process)
In the fusing step, the aggregates are melt-integrated by heat-treating the aggregates. In addition, when encapsulating resin fine particles are formed by forming a resin coating layer on the aggregate, the polymer constituting the aggregate and the resin coating layer on the surface thereof are integrated by heat treatment. It will be. Thereby, the pigment particles are obtained in a form that is not substantially exposed on the surface.

  The temperature of the heat treatment in the fusion step is set to a temperature equal to or higher than the glass transition temperature (Tg) of the polymer primary particles constituting the aggregate. Moreover, when a resin coating layer is formed, it is set as the temperature more than the glass transition temperature (Tg) of the polymer component which forms a resin coating layer. Although specific temperature conditions are arbitrary, it is preferable that it is 5 degreeC or more normally higher than the glass transition temperature (Tg) of the polymer component which forms a resin coating layer. Although there is no restriction | limiting in the upper limit, below 50 degreeC higher than the glass transition temperature (Tg) of the polymer component which forms a resin coating layer is preferable. The heat treatment time is usually 0.5 to 6 hours, although it depends on the treatment capacity and the production amount.

(Washing / drying process)
When the above-described steps are performed in a liquid medium, after the fusing step, the encapsulated resin particles obtained are washed and dried to remove the liquid medium, thereby obtaining a toner. There are no restrictions on the washing and drying methods, and they are arbitrary.

<Physical properties relating to toner particle size>
There is no restriction on the volume average particle diameter (Dv) of the toner in the present invention, and it is arbitrary as long as the effect of the present invention is not significantly impaired. Usually, it is 4 μm or more, preferably 5 μm or more, and usually 10 μm or less, preferably 8 μm or less. It is. If the volume average particle diameter (Dv) of the toner is too small, the stability of the image quality may be lowered, and if it is too large, the resolution may be lowered.

  In the toner of the present invention, the value (Dv / Dn) obtained by dividing the volume average particle diameter (Dv) by the number average particle diameter (Dn) is usually 1.0 or more, and usually 1.25 or less, preferably 1.20 or less, more preferably 1.15 or less. The value of (Dv / Dn) represents the state of the particle size distribution, and the closer this value is to 1.0, the sharper the particle size distribution. A sharper particle size distribution is desirable because the chargeability of the toner becomes uniform.

  Furthermore, the toner in the present invention has a volume fraction of a volume average particle diameter (Dv) of 25 μm or more, usually 1% or less, preferably 0.5% or less, more preferably 0.1% or less, and still more preferably 0.8. 05% or less. The smaller this value, the better. This means that the ratio of the coarse powder contained in the toner is small. If the coarse powder is small, the amount of toner consumed during continuous development is small and the image quality is stabilized. In addition, although it is preferable that there is no coarse powder having a particle size of 25 μm or more, it is difficult in actual production, and it is usually not necessary to make it 0.005% or less.

  Further, the toner in the present invention has a volume average particle size (Dv) of 15 μm or more, usually 2% or less, preferably 1% or less, more preferably 0.1% or less. It is preferable that there is no coarse powder having a particle size of 15 μm or more, but it is difficult in actual production, and it is usually not necessary to make it 0.01% or less.

  Further, in the toner of the present invention, the number fraction having a volume average particle diameter (Dv) of 5 μm or less is usually 15% or less, preferably 10% or less from the viewpoint of improving the image fog.

  Here, the volume average particle diameter (Dv), number average particle diameter (Dn), volume fraction, number fraction, etc. of the toner are measured as follows. In other words, a Coulter Counter Multisizer II or III (manufactured by Beckman Coulter, Inc.) is used as a toner particle size measuring device, and an interface for outputting the number distribution and volume distribution and a general personal computer are connected. To use. In addition, Isoton II is used as the electrolytic solution. As a measuring method, 0.1 to 5 mL of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 mL of the electrolytic solution, and 2 to 20 mg of a measurement sample (toner) is further added. Then, the electrolytic solution in which the sample is suspended is subjected to dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and measured with a 100 μm aperture by the multisizer type II or type III of the Coulter counter. Thus, the number and volume of the toner are measured to calculate the number distribution and the volume distribution, respectively, and the volume average particle diameter (Dv) and the number average particle diameter (Dn) are obtained, respectively.

<Physical properties related to the peak molecular weight of the toner>
In the present invention, at least one of the peak molecular weights in the gel permeation chromatography (hereinafter sometimes abbreviated as “GPC”) of the THF soluble content of the toner in the present invention is usually 10,000 or more, preferably 20,000 or more. Preferably it is 30,000 or more, and is 150,000 or less normally, Preferably it is 100,000 or less, More preferably, it is 70,000 or less. Note that THF is tetrahydrofuran. When the peak molecular weight is lower than the above range, the mechanical durability in the non-magnetic one-component development method may be deteriorated. When the peak molecular weight is higher than the above range, the low temperature fixability and the fixing strength are deteriorated. There is a case.

  Further, the THF-insoluble content of the toner is usually 10% or more, preferably 20% or more, and usually 60% or less, preferably 50% or less, as measured by a weight method by Celite filtration described later. If it is not within the above range, it may be difficult to achieve both mechanical durability and low-temperature fixability.

The peak molecular weight of the toner in the present invention is measured under the following conditions using a measuring apparatus: HLC-8120GPC (manufactured by Tosoh Corporation). That is, the column is stabilized in a heat chamber at 40 ° C., and tetrahydrofuran (THF) as a solvent is allowed to flow through the column at this temperature at a flow rate of 1 mL (milliliter) per minute. Next, the toner is dissolved in THF and filtered through a 0.2 μm filter, and the filtrate is used as a sample. The measurement is performed by injecting 50 to 200 μL of a THF solution of a resin with the sample concentration (concentration of the resin in the toner) adjusted to 0.05 to 0.6% by mass into the measuring device. 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 , 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ are used, and at least about 10 standard polystyrene samples are used. An RI (refractive index) detector is used as the detector.

Furthermore, as a column used in the measurement method, in order to accurately measure a molecular weight region of 10 ³ to 2 × 10 ⁶ , it is preferable to combine a plurality of commercially available polystyrene gel columns, for example, manufactured by Waters A combination of μ-styragels 500, 103, 104, and 105 and a combination of shodex KA801, 802, 803, 804, 805, 806, and 807 manufactured by Showa Denko KK are preferable.

  The measurement of the insoluble content of tetrahydrofuran (THF) in the toner is performed as follows. That is, 1 g of a sample (toner) was added to 100 g of THF, and allowed to stand at 25 ° C. for 24 hours. The mixture was filtered using 10 g of Celite, the solvent of the filtrate was distilled off, and the THF-soluble matter was quantified. Insoluble matter can be calculated.

<Softening point and glass transition temperature of toner>
There is no restriction on the softening point (Sp) of the toner in the present invention, and it is optional as long as the effects of the present invention are not significantly impaired. From the viewpoint of fixing with low energy, it is usually 150 ° C. or lower, preferably 140 ° C. or lower. Further, from the viewpoint of high temperature offset resistance and durability, the softening point is usually 80 ° C. or higher, preferably 100 ° C. or higher. The softening point (Sp) of the toner is measured with a flow tester under the conditions of 1.0 g of a sample of 1 mm × 10 mm nozzle, a load of 30 kg, a preheating time of 50 ° C. for 5 minutes, and a heating rate of 3 ° C./min. The temperature at the midpoint of the strand from the start to the end of the flow.

  Further, there is no limitation on the glass transition temperature (Tg) of the toner in the present invention, and it is optional as long as the effects of the present invention are not significantly impaired. It is preferable in that it can be performed. The glass transition temperature (Tg) is usually 40 ° C. or higher, preferably 50 ° C. or higher, from the viewpoint of blocking resistance. The glass transition temperature (Tg) of the toner is obtained by drawing a tangent line at the start of the transition (inflection) of the curve measured with a differential scanning calorimeter at a temperature increase rate of 10 ° C./min. Calculate as temperature.

  The softening point (Sp) and glass transition temperature (Tg) of the toner are greatly affected by the type and composition ratio of the polymer contained in the toner. Therefore, the softening point (Sp) and glass transition temperature (Tg) of the toner can be adjusted by appropriately optimizing the type and composition of the polymer. It can also be adjusted by the molecular weight of the polymer, the gel content, the kind of low melting point components such as wax, and the blending amount.

<Wax in toner>
When the toner in the present invention contains a wax, the dispersed particle diameter of the wax in the toner particles is usually 0.1 μm or more, preferably 0.3 μm or more as an average particle diameter, and the upper limit is usually 3 μm or less. Preferably it is 1 micrometer or less. If the dispersed particle size is too small, the effect of improving the filming resistance of the toner may not be obtained. If the dispersed particle size is too large, the wax will be easily exposed on the surface of the toner and the chargeability and heat resistance will decrease. There is a case. The dispersed particle diameter of the wax may be determined by observing an electron microscope after slicing the toner, or wax particles remaining on the filter after elution of the toner polymer with an organic solvent or the like in which the wax does not dissolve. There is a method of measuring with a microscope.

  Further, the ratio of the wax in the toner is arbitrary as long as the effects of the present invention are not significantly impaired, but it is usually 0.05% by mass or more, preferably 0.1% by mass or more, and usually 20% by mass or less, preferably Is 15% by mass or less. If the amount of wax is too small, the fixing temperature range may be insufficient. If the amount is too large, the apparatus member may be contaminated and the image quality may deteriorate.

<Externally added fine particles>
In order to improve toner fluidity, charging stability, anti-blocking property at high temperature, and the like, external additive fine particles may be attached to the surface of the toner particles. As a method for attaching the externally added fine particles to the toner particle surface, for example, in the above-described toner manufacturing method, the secondary aggregate and the externally added fine particles are mixed in a liquid medium and then heated to externally add the toner particles onto the toner particles. Examples include a method of fixing fine particles; a method of mixing or fixing externally added fine particles to toner particles obtained by separating, washing, and drying secondary aggregates from a liquid medium.

  Examples of the mixer used when the toner particles and the externally added fine particles are mixed in a dry process include a Henschel mixer, a super mixer, a Nauter mixer, a V-type mixer, a Redige mixer, a double cone mixer, and a drum type mixer. Can be mentioned. Among them, it is preferable to use a high-speed agitation type mixer such as a Henschel mixer, a super mixer, etc., and appropriately mix the mixture by stirring and mixing uniformly by appropriately setting the blade shape, the number of revolutions, the time, the number of times of driving and stopping, etc. .

  In addition, as a device used for fixing toner particles and externally added fine particles in a dry method, a compression shearing device that can apply compressive shear stress, a particle surface melting device that can melt the particle surface, etc. Is mentioned. A compression shearing apparatus generally has a narrow gap portion composed of a head surface and a head surface, a head surface and a wall surface, or a wall surface and a wall surface that move relatively while maintaining a gap, and particles to be processed are disposed in the gap. By being forced to pass through the portion, compressive stress and shear stress are applied to the particle surface without substantial pulverization. An example of such a compression shearing apparatus is a mechanofusion apparatus manufactured by Hosokawa Micron.

  On the other hand, the particle surface melting treatment apparatus is generally configured so as to fix the externally added fine particles by using a hot air stream or the like and instantaneously heating the mixture of the basic fine particles and the externally added fine particles to a temperature higher than the melting start temperature of the basic fine particles. The Examples of such a particle surface melting apparatus include a surfing system manufactured by Nippon Pneumatic Co., Ltd.

As the externally added fine particles, known fine particles that can be used for this purpose can be used. Examples thereof include inorganic fine particles and organic fine particles. As the inorganic fine particles, for example,
Carbides such as silicon carbide, boron carbide, titanium carbide, zirconium carbide, hafnium carbide, vanadium carbide, tantalum carbide, niobium carbide, tungsten carbide, chromium carbide, molybdenum carbide, calcium carbide,
Nitrides such as boron nitride, titanium nitride, zirconium nitride, silicon nitride,
Borides such as zirconium boride,
Oxides and hydroxides such as silica, colloidal silica, titanium oxide, aluminum oxide, calcium oxide, magnesium oxide, zinc oxide, copper oxide, zirconium oxide, cerium oxide, talc, hydrotalcite,
Various titanate compounds such as calcium titanate, magnesium titanate, strontium titanate, barium titanate,
Phosphate compounds such as tricalcium phosphate, calcium dihydrogen phosphate, calcium monohydrogen phosphate, substituted calcium phosphate in which a part of phosphate ion is replaced by an anion,
Sulfides such as molybdenum disulfide,
Fluorides such as magnesium fluoride and carbon fluoride,
Metal soaps such as aluminum stearate, calcium stearate, zinc stearate, magnesium stearate,
Examples of the carbon black include talc, bentonite, and conductive carbon black. Furthermore, magnetic materials such as magnetite, maghematite, and an intermediate between magnetite and maghematite may be used.

  On the other hand, as the organic fine particles, for example, styrene resin, acrylic resin such as polymethyl acrylate and polymethyl methacrylate, epoxy resin, melamine resin, tetrafluoroethylene resin, trifluoroethylene resin, polyvinyl chloride, Fine particles such as polyethylene and polyacrylonitrile are listed.

  Among these externally added fine particles, silica, titanium oxide, alumina, zinc oxide, carbon black and the like are preferable. In addition, 1 type may be used for an external addition fine particle, and 2 or more types may be used together by arbitrary combinations and a ratio.

  In addition, the surface of these inorganic or organic fine particles is a silane coupling agent, titanate coupling agent, silicone oil, modified silicone oil, silicone varnish, fluorine silane coupling agent, fluorine silicone oil, amino group or fourth group. Surface treatment such as hydrophobization may be performed by a treating agent such as a coupling agent having a quaternary ammonium base. In addition, 1 type may be used for a processing agent and it may use 2 or more types together by arbitrary combinations and a ratio.

  Further, the number average particle diameter of the externally added fine particles is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.001 μm or more, preferably 0.005 μm or more, and usually 3 μm or less, preferably 1 μm or less. A plurality of those having different average particle diameters may be blended. The average particle diameter of the externally added fine particles is obtained by observation with an electron microscope, conversion from a value of a BET specific surface area, or the like.

  The ratio of the externally added fine particles to the toner is arbitrary as long as the effects of the present invention are not significantly impaired. However, the ratio of the externally added fine particles to the total mass of the toner and the externally added fine particles is usually 0.1% by mass or more, preferably 0.3% by mass or more, more preferably 0.5% by mass or more, and usually 10%. It is at most 6% by mass, preferably at most 6% by mass, more preferably at most 4% by mass. If the amount of externally added fine particles is too small, fluidity and charging stability may be insufficient, and if the amount is too large, fixability may be deteriorated.

<Others>
The charging characteristics of the toner in the present invention may be negatively charged or positively charged, and can be set according to the method of the image forming apparatus used. The charging characteristics of the toner can be adjusted by the selection and composition ratio of the toner base particle composition such as the charge control agent, the selection and composition ratio of the externally added fine particles.

  Further, the toner in the present invention can be used as a one-component developer, or mixed with a carrier and used as a two-component developer. When used as a two-component developer, the carrier that is mixed with the toner to form the developer may be, for example, a known magnetic substance such as an iron powder-based, ferrite-based, or magnetite-based carrier, or a resin coating on the surface thereof. Applied ones or magnetic resin carriers can be used.

  As the carrier coating resin, for example, generally known styrene resins, acrylic resins, styrene acrylic copolymer resins, silicone resins, modified silicone resins, fluorine resins, and the like can be used. Is not to be done.

  The average particle diameter of the carrier is not particularly limited, but those having an average particle diameter of 10 to 200 μm are preferable. These carriers are preferably used at a ratio of 5 to 100 parts by mass with respect to 1 part by mass of the toner.

  It should be noted that the formation of a full-color image by electrophotography can be carried out in a conventional manner using magenta, cyan, and yellow color toners and, if necessary, black toner.

[Image forming apparatus]
Next, an embodiment of an image forming apparatus using the electrophotographic photosensitive member of the present invention will be described with reference to FIG. However, the embodiment is not limited to the following description, and can be arbitrarily modified without departing from the gist of the present invention.

  As shown in FIG. 1, the image forming apparatus includes an electrophotographic photosensitive member 1, a charging device 2, an exposure device 3, a developing device 4, and a transfer device 5, and further includes a cleaning device 6 and a fixing device as necessary. A device 7 is provided.

  The electrophotographic photoreceptor 1 is not particularly limited as long as it is the above-described electrophotographic photoreceptor of the present invention, but in FIG. 1, as an example, a drum in which the above-described photosensitive layer is formed on the surface of a cylindrical conductive support. The electrophotographic photosensitive member is shown. A charging device 2, an exposure device 3, a developing device 4, a transfer device 5, and a cleaning device 6 are disposed along the outer peripheral surface of the electrophotographic photosensitive member 1.

  The charging device 2 charges the electrophotographic photosensitive member 1 and uniformly charges the surface of the electrophotographic photosensitive member 1 to a predetermined potential. In FIG. 1, a roller type charging device (charging roller) is shown as an example of the charging device 2, but a corona charging device such as a corotron or a scorotron, a contact type charging device such as a charging brush, etc. are often used.

  In many cases, the electrophotographic photosensitive member 1 and the charging device 2 are designed so as to be removable from the main body of the image forming apparatus as a cartridge having both of them (hereinafter sometimes referred to as “electrophotographic photosensitive member cartridge”). In the present invention, it is desirable to use such a form.

  In the present invention, as described above, when the charging unit is disposed in contact with the electrophotographic photosensitive member, the effect is remarkably exhibited, so this configuration is desirable. For example, when the electrophotographic photosensitive member 1 or the charging device 2 is deteriorated, the electrophotographic photosensitive member cartridge can be removed from the main body of the image forming apparatus and another new electrophotographic photosensitive member cartridge can be mounted on the main body of the image forming apparatus. It can be done. Also, the toner described above is often stored in the toner cartridge and designed to be removable from the main body of the image forming apparatus. When the toner in the used toner cartridge runs out, the toner cartridge is removed. It can be removed from the main body of the image forming apparatus and another new toner cartridge can be mounted.

  The electrophotographic photosensitive member cartridge includes the electrophotographic photosensitive member, a charging unit that charges the electrophotographic photosensitive member, an exposure unit that exposes the charged electrophotographic photosensitive member to form an electrostatic latent image, and the electrophotographic photosensitive member. It is preferable to include at least one of a developing unit for developing the electrostatic latent image formed thereon and a cleaning unit for cleaning the electrophotographic photosensitive member. Further, a cartridge provided with all of the electrophotographic photosensitive member, the charging device and the toner is particularly preferable.

  The type of the exposure apparatus 3 is not particularly limited as long as it can expose the electrophotographic photoreceptor 1 to form an electrostatic latent image on the photosensitive surface of the electrophotographic photoreceptor 1. Specific examples include halogen lamps, fluorescent lamps, lasers such as semiconductor lasers and He—Ne lasers, LEDs, and the like. Further, exposure may be performed by a photoreceptor internal exposure method. The light used for the exposure is arbitrary. For example, the exposure may be performed using monochromatic light having a wavelength of 780 nm, monochromatic light having a wavelength of 600 nm to 700 nm, slightly short wavelength, monochromatic light having a wavelength of 350 nm to 600 nm, or the like. . Among these, it is preferable to expose with monochromatic light having a short wavelength of 350 nm to 600 nm, and more preferably to expose with monochromatic light having a wavelength of 380 nm to 500 nm.

  The electrophotographic photosensitive member of the present invention is excellent in image characteristics represented by fog characteristics and the like, and is also excellent in dot dropout characteristics. Therefore, when forming a higher resolution image in which these defects are likely to occur. In particular, the image forming apparatus of the present invention preferably has a resolution of an electrostatic latent image of 1200 dpi or more in that a particularly remarkable effect can be obtained.

  The type of the developing device 4 is not particularly limited, and any device such as a dry development method such as cascade development, one-component conductive toner development, two-component magnetic brush development, or a wet development method can be used. In FIG. 1, the developing device 4 includes a developing tank 41, an agitator 42, a supply roller 43, a developing roller 44, and a regulating member 45, and has a configuration in which toner T is stored inside the developing tank 41. . Further, a replenishing device (not shown) for replenishing the toner T may be attached to the developing device 4 as necessary. This replenishing device is configured to be able to replenish toner T from a container such as a bottle or a cartridge.

  The supply roller 43 is formed from a conductive sponge or the like. The developing roller 44 is made of a metal roll such as iron, stainless steel, aluminum, or nickel, or a resin roll obtained by coating such a metal roll with a silicone resin, a urethane resin, a fluororesin, or the like. The surface of the developing roller 44 may be smoothed or roughened as necessary.

  The developing roller 44 is disposed between the electrophotographic photoreceptor 1 and the supply roller 43 and is in contact with the electrophotographic photoreceptor 1 and the supply roller 43, respectively. The supply roller 43 and the developing roller 44 are rotated by a rotation drive mechanism (not shown). The supply roller 43 carries the stored toner T and supplies it to the developing roller 44. The developing roller 44 carries the toner T supplied by the supply roller 43 and contacts the surface of the electrophotographic photosensitive member 1.

  The regulating member 45 is formed of a resin blade such as a silicone resin or a urethane resin, a metal blade such as stainless steel, aluminum, copper, brass, or bronze, or a blade obtained by coating such a metal blade with a resin. The regulating member 45 contacts the developing roller 44 and is pressed against the developing roller 44 side with a predetermined force by a spring or the like (a general blade linear pressure is 5 to 500 g / cm). If necessary, the regulating member 45 may be provided with a function of imparting charging to the toner T by frictional charging with the toner T.

  The agitator 42 is rotated by a rotation driving mechanism, and agitates the toner T and conveys the toner T to the supply roller 43 side. A plurality of agitators 42 may be provided with different blade shapes and sizes.

  The toner T is as described above.

  The type of the transfer device 5 is not particularly limited, and an apparatus using an arbitrary system such as an electrostatic transfer method such as corona transfer, roller transfer, or belt transfer, a pressure transfer method, or an adhesive transfer method can be used. . Here, it is assumed that the transfer device 5 includes a transfer charger, a transfer roller, a transfer belt, and the like disposed so as to face the electrophotographic photoreceptor 1. The transfer device 5 applies a predetermined voltage value (transfer voltage) having a polarity opposite to the charging potential of the toner T, and transfers the toner image formed on the electrophotographic photosensitive member 1 to a transfer material (paper, medium) P. Is. In the present invention, it is effective when the transfer device 5 is placed in contact with the electrophotographic photoreceptor 1 via a transfer material.

  There is no restriction | limiting in particular about the cleaning apparatus 6, Arbitrary cleaning apparatuses, such as a brush cleaner, a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a blade cleaner, can be used. The cleaning device 6 scrapes the residual toner adhering to the electrophotographic photosensitive member 1 with a cleaning member and collects the residual toner. However, when there is little or almost no toner remaining on the surface of the electrophotographic photosensitive member, the cleaning device 6 may be omitted.

  The fixing device 7 includes an upper fixing member (fixing roller) 71 and a lower fixing member (fixing roller) 72, and a heating device 73 is provided inside the fixing member 71 or 72. FIG. 1 shows an example in which a heating device 73 is provided inside the upper fixing member 71. As the upper and lower fixing members 71 and 72, a known heat fixing member such as a fixing roll in which a metal base tube such as stainless steel or aluminum is coated with silicon rubber, a fixing roll coated with a fluororesin, or a fixing sheet is used. be able to. Further, the fixing members 71 and 72 may be configured to supply a release agent such as silicone oil in order to improve the releasability, or may be configured to forcibly apply pressure to each other by a spring or the like.

  When the toner transferred onto the recording paper P passes between the upper fixing member 71 and the lower fixing member 72 heated to a predetermined temperature, the toner is heated to a molten state and cooled after passing through the recording paper. Toner is fixed on P. The type of the fixing device is not particularly limited, and a fixing device of an arbitrary method such as heat roller fixing, flash fixing, oven fixing, pressure fixing, or the like can be provided.

[Image forming method]
In the image forming apparatus configured as described above, an image is recorded as follows. That is, first, the surface (photosensitive surface) of the electrophotographic photosensitive member 1 is charged to a predetermined potential (for example, −600 V) by the charging device 2. At this time, charging may be performed with a DC voltage, or charging may be performed by superimposing an AC voltage on the DC voltage. Subsequently, the photosensitive surface of the charged electrophotographic photosensitive member 1 is exposed by the exposure device 3 according to the image to be recorded, and an electrostatic latent image is formed on the photosensitive surface. Then, development of the electrostatic latent image formed on the photosensitive surface of the electrophotographic photoreceptor 1 is performed by the developing device 4.

  The developing device 4 thins the toner T supplied by the supply roller 43 with a regulating member (developing blade) 45 and has a predetermined polarity (here, the same polarity as the charging potential of the electrophotographic photosensitive member 1). Negatively charged) and conveyed while being carried on the developing roller 44 and brought into contact with the surface of the electrophotographic photosensitive member 1. When the charged toner T carried on the developing roller 44 contacts the surface of the electrophotographic photoreceptor 1, a toner image corresponding to the electrostatic latent image is formed on the photosensitive surface of the electrophotographic photoreceptor 1. This toner image is transferred onto the recording paper P by the transfer device 5. Thereafter, the toner remaining on the photosensitive surface of the electrophotographic photosensitive member 1 without being transferred is removed by the cleaning device 6.

  After the transfer of the toner image onto the recording paper P, the final image is obtained by passing the fixing device 7 and thermally fixing the toner image onto the recording paper P. In addition to the above-described configuration, the image forming apparatus may be configured to perform, for example, a static elimination process. The neutralization step is a step of neutralizing the electrophotographic photosensitive member by exposing the electrophotographic photosensitive member, and a fluorescent lamp, an LED, or the like is used as the neutralizing device. In addition, the light used in the static elimination process is often light having an exposure energy that is at least three times that of the exposure light.

  The image forming apparatus may be further modified. For example, the image forming apparatus may be configured to perform a pre-exposure process, an auxiliary charging process, or the like, or may be configured to perform offset printing. A full-color tandem system configuration using toner may be used.

  Hereinafter, the present invention will be described in more detail with reference to examples, comparative examples, and reference examples, but the present invention is not limited to these unless it exceeds the gist. In the following examples, comparative examples and reference examples, “parts” indicates “parts by mass” unless otherwise specified, and “%” indicates “mass%” unless otherwise specified.

Example 1
High-speed fluidized mixing of rutile type titanium oxide having an average primary particle diameter of 40 nm (“TTO55N” manufactured by Ishihara Sangyo Co., Ltd.) and 3% by mass of methyldimethoxysilane (“TSL8117” manufactured by Toshiba Silicone Co., Ltd.) The surface-treated titanium oxide obtained by charging a kneading machine (“SMG300” manufactured by Kawata Co., Ltd.) and mixing at high speed at a rotational peripheral speed of 34.5 m / sec. Has a mass ratio of methanol / 1-propanol of 7 / A dispersion slurry of hydrophobized titanium oxide was obtained by dispersing with a ball mill in the mixed solvent No. 3. The dispersion slurry, a mixed solvent of methanol / 1-propanol / toluene, and ε-caprolactam [compound represented by the following formula (A)] / bis (described in Examples of JP-A-4-31870) / bis ( 4-amino-3-methylcyclohexyl) methane [compound represented by the following formula (B)] / hexamethylenediamine [compound represented by the following formula (C)] / decamethylene dicarboxylic acid [represented by the following formula (D) Compound] / octadecamethylenedicarboxylic acid [compound represented by the following formula (E)] is heated with a copolyamide pellet having a composition molar ratio of 60% / 15% / 5% / 15% / 5%. While stirring and mixing, the polyamide pellets are dissolved, and then ultrasonic dispersion treatment is performed to obtain methanol / 1-propanol / toluene. Mass ratio is 7/1/2, containing a hydrophobic-treated titanium oxide / copolymerized polyamide in a weight ratio of 3/1, to prepare a dispersion A for undercoat layer having a solid concentration of 18.0%.

By immersing an anodized aluminum cylinder (outer diameter 30 mm, length 351 mm, thickness 1.0 mm) in this undercoat layer forming dispersion A, the film thickness after drying becomes 1.5 μm. Thus, the undercoat layer was formed by dip coating. Next, as a charge generation material, 20 parts of D-type oxytitanium phthalocyanine and 280 parts of 1,2-dimethoxyethane were mixed and pulverized with a sand grind mill for 2 hours for atomization dispersion treatment. Subsequently, 253 parts of 1,2-dimethoxyethane was added to polyvinyl butyral (trade name “Denkabutyral” # 6000C, manufactured by Denki Kagaku Kogyo Co., Ltd.), and 4-methoxy-4-methyl-2-butylene. A dispersion liquid for forming a charge generation layer was prepared by mixing a binder liquid obtained by dissolving pentanone in 85 parts of a mixed liquid and 230 parts of 1,2-dimethoxyethane. The aluminum cylinder provided with the undercoat layer is immersed in the dispersion for forming the charge generation layer, and the charge generation layer is dip-coated so that the film thickness after drying is 0.3 μm (0.3 g / m ² ). Formed.

下記構造を有する酸化防止剤８部、

及びレベリング剤としてシリコーンオイル（商品名 ＫＦ９６ 信越化学工業（株））０．０３部を、テトラヒドロフラン／トルエン（８／２）混合溶媒６４０部に溶解させた液を、上述の電荷発生層上に、乾燥後の膜厚が１８μｍとなるように浸漬塗布し、積層型感光層を有する電子写真感光体Ｅ１を得た。 Next, as a charge transport material, 56 parts of the following compound CT-1, 14 parts of the following compound CT-2, 1.5 parts of the following compound AD-1 and 0. 1 part and 100 parts of a polycarbonate having the following structure P-1 as a repeating unit as a binder resin (P-1: viscosity average molecular weight of about 30,000),

8 parts of an antioxidant having the following structure:

In addition, a liquid obtained by dissolving 0.03 part of silicone oil (trade name: KF96 Shin-Etsu Chemical Co., Ltd.) as a leveling agent in 640 parts of a tetrahydrofuran / toluene (8/2) mixed solvent is placed on the charge generation layer. The electrophotographic photoreceptor E1 having a laminated photosensitive layer was obtained by dip coating so that the film thickness after drying was 18 μm.

Example 2
Instead of using 0.1 part by mass of the compound represented by Example Compound 1 used in Example 1, an electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that 1.0 part by mass was used. Photoconductor E2 was obtained.

Example 3
An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that the following general formula (P-2: viscosity average molecular weight of about 40,000, x: y: z = 45/45/10) was used. Body E3 was obtained.

Example 4
Instead of using the general formula (P-1) as the binder, the same as in Example 1 except that the following general formula (P-3: viscosity average molecular weight of about 40,000, m: n = 1: 1) is used. Thus, an electrophotographic photoreceptor E4 was obtained.

Example 5
Instead of using the general formula (P-1) as the binder, the same as in Example 1 except that the following general formula (P-4: viscosity average molecular weight of about 30,000, m: n = 3: 7) is used. Thus, an electrophotographic photoreceptor E5 was obtained.

Example 6
Instead of using the general formula (P-1) as a binder, the following general formula (P-5: viscosity average molecular weight of about 30,000, m: n = 3: 7) is used, and the compound CT- 1. Instead of using CT-2, an electrophotographic photoreceptor E6 was obtained in the same manner as in Example 1 except that 60 parts of the following compound CT-3 was used.

Example 7
An electrophotographic photoreceptor E7 is obtained in the same manner as in Example 6 except that instead of using the general formula (P-5) as a binder, the following general formula (P-6: viscosity average molecular weight of about 30,000) is used. It was.

Example 8
Instead of using 0.1 part of Exemplified Compound 1 used in Example 1, 0.1 part of Exemplified Compound 37 is used, and 40 parts of the following Compound CT-4 is used instead of CT-1 and CT-2. Except that, an electrophotographic photosensitive member E8 was obtained in the same manner as in Example 1.

Example 9
A rutile type titanium oxide having an average primary particle size of 40 nm (“TTO55N” manufactured by Ishihara Sangyo Co., Ltd.) and 3% by mass of methyldimethoxysilane (“TSL8117” manufactured by Toshiba Silicone Co., Ltd.) with respect to the titanium oxide were added to a Henschel mixer. 1 kg of a raw slurry obtained by mixing 50 parts of surface-treated titanium oxide obtained by mixing with 120 parts of methanol, and using a zirconia bead having a diameter of about 100 μm (YTZ manufactured by Nikkato Co., Ltd.) as a dispersion medium, a mill volume of about 0 Using a 15-liter Ultra Apex Mill (UAM-015 type) manufactured by Kotobuki Kogyo Co., Ltd., a titanium oxide dispersion was prepared by dispersing for 1 hour in a liquid circulation state with a rotor peripheral speed of 10 m / second and a liquid flow rate of 10 kg / hour. .

The titanium oxide dispersion, a mixed solvent of methanol / 1-propanol / toluene and ε-caprolactam [compound represented by the following formula (A)] / bis (4-amino-3-methylcyclohexyl) methane [the following formula (B Compound represented by the following formula (C)] / decamethylene dicarboxylic acid [compound represented by the following formula (D)] / octadecamethylene dicarboxylic acid [in the following formula (E) The compositional molar ratio of the compound represented] is 60% / 15% / 5% / 15% / 5% of the copolymerized polyamide pellets with heating and stirring and mixing to dissolve the polyamide pellets, and then output. Ultrasonic dispersion treatment with a 1200 W ultrasonic transmitter is performed for 1 hour, and further a PTFE membrane filter (Advante) with a pore diameter of 5 μm. And the mass ratio of the surface-treated titanium oxide / copolymerized polyamide is 3/1 and the mass ratio of the mixed solvent of methanol / 1-propanol / toluene is 7/1/2. Thus, an undercoat layer forming dispersion B having a solid content concentration of 18.0% by mass was obtained.

The undercoat layer forming coating solution B is dip-coated on an anodized aluminum cylinder (outer diameter 30 mm, length 351 mm, thickness 1.0 mm), and the film thickness after drying is 1.5 μm. A pull layer was provided. The undercoat layer 94.2Cm ^2, methanol 70cm ^3, 1-propanol 30cm was immersed in a mixed liquid for ^3, to obtain an undercoat layer dispersion was sonicated for 5 minutes using an ultrasonic oscillator output 600W The particle size distribution of the metal oxide particles in the dispersion was measured by UPA as in Example 1. As a result, the volume average diameter Mv was 0.078 μm, the number average diameter Mp was 0.059 μm, and Mv / Mp was 1. 32. On the obtained undercoat layer, a charge generation layer and a charge transport layer were formed in the same manner as in Example 1 to obtain an electrophotographic photoreceptor E9.

After 94.2 cm ² of the photosensitive layer of the obtained electrophotographic photoreceptor E9 was immersed in 100 cm ³ of tetrahydrofuran and dissolved and removed by ultrasonic treatment for 5 minutes with an ultrasonic transmitter with an output of 600 W, the same portion was treated with 70 cm ³ of methanol. Then, it is immersed in a mixing liquid of 1-propanol 30 cm ³ and subjected to ultrasonic treatment for 5 minutes with an ultrasonic transmitter having an output of 600 W to obtain an undercoat layer dispersion, and the particle size distribution of the metal oxide particles in the dispersion The volume average diameter Mv was 0.079 μm, the number average diameter Mp was 0.059 μm, and Mv / Mp was 1.34.

Comparative Example 1 to Comparative Example 9
Electrophotographic photoreceptors P1 to P9 were prepared in the same manner as in Examples 1 to 9, except that the compounds represented by the formula (1) (Exemplary Compound 1, Exemplified Compound 37) were not used.

Comparative Example 10
An electrophotographic photosensitive member P10 was prepared in the same manner as in Example 1 except that 0.1 part of the following compound was used instead of 0.1 part of the exemplified compound 1.

<Evaluation of electrical characteristics>
The electrophotographic photosensitive member produced in the examples and comparative examples was prepared by electrophotographic characteristic evaluation apparatus produced in accordance with the standard of the electrophotographic society (basic and applied electrophotographic technology, edited by the Electrophotographic Society, Corona, pages 404-405). In accordance with the following procedure, the electrical characteristics were evaluated by a cycle of charging (negative polarity), exposure, potential measurement, and static elimination.

Irradiation energy (when the surface potential is -350 V by irradiating the electrophotographic photosensitive member so that the initial surface potential is -700 V and irradiating the halogen lamp with 780 nm monochromatic light by an interference filter) The half exposure energy) was measured as sensitivity (E1 / 2) (μJ / cm ² ). Further, the post-exposure surface potential (VL1) after 233 ms when the exposure light was irradiated at an intensity of 1.0 μJ / cm ² was measured (−V). The results are shown in Table 1.

<Image evaluation-1>
Example G1
The electrophotographic photoreceptor E8 was mounted on a cyan drum cartridge of a commercially available tandem type color printer (Microline 3050c manufactured by Oki Data Co.) that is compatible with A3 printing, and mounted on the printer. First, under the conditions of a temperature of 35 ° C. and a humidity of 80%, the printing media type was set to OHP, and 100 sheets of cyan images were printed on the A4 version OHP film MC502 manufactured by Mitsubishi Chemical Media Corporation by vertical feeding. Next, a solid cyan image was printed on A3 paper, and image evaluation was performed.

  As a result, the OHP sheet passing area of the solid image printed on A3 paper (the part where the electrophotographic photosensitive member is damaged by the transfer through the OHP sheet) and the OHP non-sheet passing area (the electrophotographic photosensitive member is directly transferred) The density difference of the damaged part) was not confirmed.

<Image evaluation-2>
(Manufacturing of developing toner 1)
-Preparation of Wax-Long Chain Polymerizable Monomer Dispersion T1 Paraffin wax (HNP-9 manufactured by Nippon Seiki Co., Ltd., surface tension 23.5 mN / m, melting point 82 ° C., heat of fusion 220 J / g, melting peak half width 8 .2 ° C., crystallization peak half width 13.0 ° C.) 27 parts (540 g), stearyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) 2.8 parts, 20% by weight sodium dodecylbenzenesulfonate aqueous solution (Daiichi Kogyo Seiyaku Co., Ltd.) 1.9 parts of Neogen S20A (hereinafter abbreviated as “20% DBS aqueous solution”) and 68.3 parts of demineralized water were heated to 90 ° C. and heated at 8000 rpm with a homomixer (Mark II f model manufactured by Tokushu Kika Kogyo Co., Ltd.). The mixture was stirred for 10 minutes at the rotation speed. Subsequently, this dispersion was heated to 90 ° C., and circulation emulsification was started under a pressure condition of about 25 MPa using a homogenizer (manufactured by Gorin Co., Ltd., 15-M-8PA type), and the volume average particle diameter was UPA-EX. While measuring, the volume average particle size was dispersed to 250 nm to prepare a wax-long chain polymerizable monomer dispersion T1 (emulsion solid content concentration = 30.2 mass%).

Preparation of silicone wax dispersion T2 27 parts (540 g) of alkyl-modified silicone wax (melting point 72 ° C.), 1.9 parts of 20% DBS aqueous solution, and 71.1 parts of demineralized water were placed in a 3 L stainless steel container and heated to 90 ° C. Then, the mixture was stirred for 10 minutes at a rotation speed of 8000 rpm with a homomixer (Mark II f model, manufactured by Koki Kogyo Co., Ltd.). Next, this dispersion was heated to 99 ° C., and circulation emulsification was started under a pressure condition of about 45 MPa using a homogenizer (manufactured by Gorin Co., Ltd., 15-M-8PA type), and the volume average particle diameter was UPA-EX. A silicone wax dispersion T2 (emulsion solid content concentration = 27.4% by mass) was prepared by dispersing until the volume average particle size was 240 nm while measuring.

-Preparation of polymer primary particle dispersion T1 Stirring device (3 blades), heating / cooling device, concentrating device, and each reactor, reactor equipped with auxiliary materials (inner volume 21L, inner diameter 250mm, height 420mm) 35.6 parts (712.12 g) of the wax-long-chain polymerizable monomer dispersion T1 and 259 parts of demineralized water were charged, and the temperature was raised to 90 ° C. under a nitrogen stream while stirring at a rotation speed of 103 rpm. did. Thereafter, a mixture of the following monomers and an aqueous emulsifier solution was added over 5 hours from the start of polymerization. The time at which the mixture of the monomers and the aqueous emulsifier solution was started to be dropped was set as the polymerization start, and the following initiator aqueous solution was added over 4.5 hours from 30 minutes after the start of the polymerization. The aqueous agent solution was added over 2 hours, and the mixture was further maintained for 1 hour while maintaining the rotation speed of 103 rpm and the internal temperature of 90 ° C.

[Monomers]
Styrene 76.8 parts (1535.0 g)
Butyl acrylate 23.2 parts Acrylic acid 1.5 parts Trichlorobromomethane 1.0 part Hexanediol diacrylate 0.7 part [Emulsifier aqueous solution]
20% DBS aqueous solution 1.0 part Demineralized water 67.1 parts [Initiator aqueous solution]
8% aqueous hydrogen peroxide solution 15.5 parts 8% L (+)-ascorbic acid aqueous solution 15.5 parts [Additional initiator aqueous solution]
8% L (+)-ascorbic acid aqueous solution 14.2 parts

  After completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle dispersion T1. The volume average particle diameter measured by UPA-EX was 280 nm, and the solid content concentration was 21.1% by mass.

-Preparation of polymer primary particle dispersion T2 Reactor (inner volume 21L, inner diameter 250mm, height 420mm) equipped with stirrer (three blades), heating / cooling device, concentrator, and each raw material and auxiliary agent charging device In addition, 23.6 parts (472.3 g) of silicone wax dispersion T2, 1.5 parts of 20% DBS aqueous solution, and 324 parts of demineralized water were charged, and the temperature was raised to 90 ° C. under a nitrogen stream at 103 rpm. While stirring, 3.2 parts of an 8% aqueous hydrogen peroxide solution and 3.2 parts of an 8% L (+)-ascorbic acid aqueous solution were added all at once. 5 minutes later, polymerization of the following mixture of monomers and emulsifier aqueous solution was started (from the time when 3.2 parts of 8% hydrogen peroxide aqueous solution and 3.2 parts of 8% L (+)-ascorbic acid aqueous solution were added all at once. After 5 minutes, the following initiator aqueous solution was added over 6 hours from the start of polymerization, and the mixture was further maintained for 1 hour while maintaining the rotation speed at 103 rpm and the internal temperature of 90 ° C.

[Monomers]
Styrene 92.5 parts (1850.0 g)
Butyl acrylate 7.5 parts Acrylic acid 1.5 parts Trichlorobromomethane 0.6 part [Emulsifier aqueous solution]
20% DBS aqueous solution 1.5 parts Demineralized water 66.2 parts [Initiator aqueous solution]
8% aqueous hydrogen peroxide solution 18.9 parts 8% L (+)-ascorbic acid aqueous solution 18.9 parts

  After completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle dispersion T2. The volume average particle diameter measured by UPA-EX was 290 nm, and the solid content concentration was 19.0% by mass.

・ Preparation of Colorant Dispersion T Manufactured by a furnace method in which a 300 L internal volume container equipped with a stirrer (propeller blade) has an ultraviolet absorbance of 0.02 and a true density of 1.8 g / cm ³ in a toluene extract. Carbon black (Mitsubishi Chemical Corporation, Mitsubishi Carbon Black MA100S) 20 parts (40 kg), 20% DBS aqueous solution 1 part, nonionic surfactant (Kao Co., Emulgen 120) 4 parts, electrical conductivity 2 μS / 75 parts of ion-exchange water of cm was added and predispersed to obtain a pigment premix solution. The conductivity was measured using a conductivity meter (a personal SC meter model SC72 and a detector SC72SN-11 manufactured by Yokogawa Electric Corporation). The volume cumulative 50% diameter (Dv50) of carbon black in the dispersion after premixing was about 90 μm. The premix solution was supplied as a raw material slurry to a wet bead mill and subjected to one-pass dispersion. The inner diameter of the stator was φ75 mm, the separator diameter was φ60 mm, the distance between the separator and the disk was 15 mm, and zirconia beads having a diameter of 50 μm (true density 6.0 g / cm ³ ) were used as the dispersing medium. The effective internal volume of the stator is about 0.5 L, and the media filling volume is 0.35 L, so the media filling rate is 70%. The premix slurry is continuously supplied from the supply port at a supply speed of about 50 L / hr by a non-pulsating metering pump, and the rotation speed of the rotor is constant (the peripheral speed of the rotor tip is about 11 m / sec), and continuously from the discharge port. As a result, the black colorant dispersion liquid T was obtained. The volume average particle diameter measured by UPA-EX was 150 nm, and the solid content concentration was 24.2% by mass.

-Production of developing mother particles T Using the following components, developing mother particles T were produced by the following procedure.
Polymer primary particle dispersion T1 95 parts as solid content (998.2 g as solid content)
Polymer primary particle dispersion T2 5 parts as solid content Colorant dispersion T 6 parts as colorant solid content 20% DBS aqueous solution 0.1 parts as solid content Stirrer (double helical blade), heating / cooling device, concentrator, In addition, a polymer primary particle dispersion T1 and a 20% DBS aqueous solution are charged into a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with each raw material and auxiliary agent charging device, and uniform for 5 minutes at an internal temperature of 12 ° C. and 40 rpm. Mixed. Subsequently, the stirring speed was increased to 250 rpm at an internal temperature of 12 ° C., and 0.52 part of FeSO ₄ · 7H ₂ O as a 5% aqueous solution of ferrous sulfate was added over 5 minutes, and then the colorant dispersion T was added. The mixture was added over 5 minutes, mixed uniformly at an internal temperature of 12 ° C. and 250 rpm, and a 0.5% aluminum sulfate aqueous solution was added dropwise under the same conditions (the solid content relative to the resin solid content was 0.10). Part). Thereafter, the temperature was raised to 53 ° C. over 75 minutes at 250 rpm, and then raised to 56 ° C. over 170 minutes. Here, when the particle size was measured with a precision particle size distribution measuring apparatus (multisizer III: manufactured by Beckman Coulter, Inc .; hereinafter abbreviated as “multisizer”) with an aperture diameter of 100 μm, the 50% volume diameter was 6. It was 7 μm.

  Thereafter, the polymer primary particle dispersion T2 was added over 3 minutes at 250 rpm, and maintained for 60 minutes. The rotation speed was reduced to 168 rpm, and 20% DBS aqueous solution (6 parts as solid content) was immediately added over 10 minutes. The temperature was raised to 90 ° C. and maintained at 168 rpm for 30 minutes after the addition. Thereafter, the slurry obtained by cooling to 30 ° C. over 20 minutes was extracted, and suction filtered with an aspirator using 5 types C (No. 5C, manufactured by Toyo Roshi Kaisha, Ltd.). The cake remaining on the filter paper is transferred to a stainless steel container with an internal volume of 10 L (L) equipped with a stirrer (propeller blade), added with 8 kg of ion exchange water having an electric conductivity of 1 μS / cm, and stirred uniformly at 50 rpm. Dispersed and then left stirring for 30 minutes. After that, suction filtration was performed with an aspirator again using filter paper of type 5 C (No. 5C manufactured by Toyo Roshi Kaisha, Ltd.), and the solid matter remaining on the filter paper was again equipped with a stirrer (propeller blade) and had an electrical conductivity of 1 μS. The sample was transferred to a container with an internal volume of 10 L containing 8 kg of ion-exchanged water / cm, and evenly dispersed by stirring at 50 rpm and kept stirring for 30 minutes. When this process was repeated 5 times, the electrical conductivity of the filtrate was 2 μS / cm. The conductivity was measured using a conductivity meter (a personal SC meter model SC72 and a detector SC72SN-11 manufactured by Yokogawa Electric Corporation). The cake obtained here was spread on a stainless pad so as to have a height of about 20 mm, and dried in a blow dryer set at 40 ° C. for 48 hours to obtain development mother particles T.

-Production of developing toner TA In a Henschel mixer with an internal volume of 10 L (diameter: 230 mm, height: 240 mm) equipped with a stirrer (Z / A0 blade) and a deflector that is perpendicular to the wall surface from the top, 100 parts of developing mother particles T (1000 g) was added, followed by 0.5 part of silica fine particles having a volume average primary particle size of 0.04 μm hydrophobized with silicone oil, and a volume average primary particle size of 0.012 μm hydrophobized with silicone oil. 2.0 parts of silica fine particles were added, stirred and mixed at 3000 rpm for 10 minutes, and sieved through 150 mesh to obtain a developing toner TA. The volume average particle diameter of the developing toner TA measured with Multisizer II was 7.05 μm, Dv / Dn was 1.14, and the average circularity measured with FPIA2000 was 0.963.

(Manufacturing toner 2)
In the above (Development toner production 1), in the production of the development mother particles T, after adding the DBS aqueous solution, the temperature was raised to 90 ° C. and held for 60 minutes. A developing toner TB was obtained in the same manner as in (Developing toner 1) except that the temperature was kept for 180 minutes. The average circularity measured by FPIA2000 was 0.981.

Example G2
A black drum cartridge for the electrophotographic photosensitive member E7 produced in Example 7 and the developing toner TA is used for a commercially available tandem LED color printer MICROLINE Pro 9800PS-E (Oki Data Co., Ltd.) that supports A3 printing. And a black toner cartridge, and the cartridge was mounted on the printer. Using this printer, after printing out 10,000 gradation images (Japan Image Society test chart), print out white background image and gradation image (Japan Image Society test chart), and use white background fog value and gradation image. The dot missing was evaluated. The results are shown in Table 2. The specifications of MICROLINE Pro 9800PS-E are as shown below.
Quadruple tandem color 36ppm, monochrome 40ppm
Resolution of electrostatic latent image: 1200 dpi
Contact roller charging (DC voltage applied)
LED exposure

  To adjust the fog value, adjust the whiteness meter so that the whiteness of the standard sample is 94.4, and measure the whiteness of the paper before printing using this whiteness meter. Then, printing was performed by inputting the signal to the laser printer described above, and then the whiteness of the paper was measured again, and the difference in whiteness before and after printing was determined. A large fog value means that the printed paper has many fine black spots and is darkened, that is, the image quality is poor. The gradation image was evaluated based on which density standard was printed without missing dots, and the density printed without missing dots was defined as the corresponding density. The smaller the corresponding density value is, the better the drawing can be at a thinner part.

Example G3
Image evaluation was performed in the same manner as in Example G2, except that the developing toner TB was used instead of the developing toner TA. The results are shown in Table 2.

Reference example G1
The electrophotographic photosensitive member E7 was mounted on a black drum cartridge of a commercially available color printer MICROLINE 3050c (manufactured by Oki Data Corporation), and mounted on the printer. As the toner, a commercially available toner manufactured by the melt kneading and pulverizing method for the printer was used, and image evaluation was performed in the same manner as in Example G2. The results are shown in Table 2. The average circularity of the toner was 0.935.

  The electrophotographic photoreceptor of the present invention has excellent electrical characteristics (particularly, electrical characteristics suitable even when light in a wide wavelength range from a short wavelength to a long wavelength is used as a light input light source), Further, even if it is used repeatedly for a long period of time, it is possible to form a good image, and therefore it is widely used in all fields where electrophotographic methods such as copying machines and printers are used.

1 Electrophotographic photoreceptor 2 Charging device (charging roller)
DESCRIPTION OF SYMBOLS 3 Exposure apparatus 4 Developing apparatus 5 Transfer apparatus 6 Cleaning apparatus 7 Fixing apparatus 41 Developing tank 42 Agitator 43 Supply roller 44 Developing roller 45 Control member 71 Upper fixing member (fixing roller)
72 Lower fixing member (fixing roller)
73 Heating device T Toner P Recording paper

Claims (7)

In an electrophotographic photosensitive member having a photosensitive layer on a conductive support, the photosensitive layer includes at least one compound represented by the following formula (1) and a polycarbonate resin represented by the following formula (P). An electrophotographic photosensitive member comprising:

[In Formula (1), R ¹ and R ² represent a phenyl group which may have an alkyl group having 30 or less carbon atoms and an alkyl group having 10 or less carbon atoms or an alkyl group which may have a substituent. , X represents a saturated hydrocarbon group having a cyclic structure having 3 to 30 carbon atoms .

On a conductive substrate comprising an electrophotographic photosensitive member having a photosensitive layer, the conductive support is subjected to anodic oxide coating, as set forth in claim 1, characterized in that those sealing treatment Electrophotographic photoreceptor . Said photosensitive layer, an electrophotographic photosensitive member according to claim 1 or claim 2, characterized in that it contains a compound having the following structure.

[The skeleton may be substituted with one or more substituents having 30 or less carbon atoms] It said photosensitive layer, an electrophotographic photosensitive member according to any one of claims 1 to claim 3, characterized in that it contains a hindered phenol compound. The electrophotographic photosensitive member according to any one of claims 1 to claim 4, charging unit for charging the electrophotographic photosensitive member, a charging exposure to form an electrostatic latent image is exposed to the electrophotographic photosensitive member was And an image forming apparatus including a developing unit that develops the electrostatic latent image formed on the electrophotographic photosensitive member. A charging unit for charging the electrophotographic photosensitive member according to any one of claims 1 to 4, an exposure unit for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image, and the electrophotographic photosensitive member. An image forming apparatus including a developing unit that develops the formed electrostatic latent image, wherein the electrophotographic photosensitive member has a photosensitive layer on a conductive support, and the photosensitive layer is represented by the following formula (1): An image forming apparatus comprising at least one compound represented by formula (1), wherein the charging method is contact charging.

[In Formula (1), R ¹ and R ² represent a phenyl group which may have an alkyl group having 30 or less carbon atoms and an alkyl group having 10 or less carbon atoms or an alkyl group which may have a substituent. , X represents a saturated hydrocarbon group having a cyclic structure having 3 to 30 carbon atoms. A charging unit for charging the electrophotographic photosensitive member according to any one of claims 1 to 4, an exposure unit for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image, and the electrophotographic photosensitive member. An image forming apparatus including a developing unit that develops the formed electrostatic latent image, wherein the electrophotographic photosensitive member has a photosensitive layer on a conductive support, and the photosensitive layer is represented by the following formula (1): An image forming apparatus comprising at least one compound represented by formula (II), wherein the exposed portion is an LED.

[In Formula (1), R ¹ and R ² represent a phenyl group which may have an alkyl group having 30 or less carbon atoms and an alkyl group having 10 or less carbon atoms or an alkyl group which may have a substituent. , X represents a saturated hydrocarbon group having a cyclic structure having 3 to 30 carbon atoms.

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