JP2011002783A - Electrophotographic photoreceptor, electrophotographic photoreceptor cartridge, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor having electric characteristics of high sensitivity and a low residual potential and capable of forming an image with high performance and high picture quality by combining an appropriate charge generating substance and a charge transporting substance, for solving such a problem that, although a large number of charge generating substances and organic photoconductive materials are known, a photoreceptor having the best characteristics can not be necessarily obtained by employing a simple combination of a charge generating substance having high sensitivity and a charge transporting substance having a high mobility and a low residual potential selected from those substances.SOLUTION: The electrophotographic photoreceptor has a photosensitive layer containing a metal-containing phthalocyanine as a charge generating substance and a tertiary naphthyl amine compound expressed by formula (1). In formula (1), Arand Areach represents an aryl group having at most 10 carbon atoms constituting an aromatic ring; R represents a substituent except for hydrogen; n represents an integer of 0 to 7; and the aryl group may have a substituent.

Description

  The present invention relates to an electrophotographic photosensitive member, an electrophotographic photosensitive member cartridge, and an image forming apparatus that use a combination of specific materials. In particular, it is an electrophotographic photosensitive member for use in laser printers, copying machines, fax machines, etc., which is very effective for LED light and semiconductor laser light, and has excellent durability, and an electrophotographic photosensitive member cartridge. And an image forming apparatus.

In recent years, electrophotographic technology has been widely applied not only to the field of copying machines, but also to various printers and printing machines, because of its excellent immediacy and high quality images.
As a photoreceptor that is the core of electrophotographic technology, conventionally, a photoreceptor using an inorganic charge generating material such as selenium, an arsenic-selenium alloy, and zinc oxide has been used, but recently, it is pollution-free. Photoconductors using organic charge generating materials that have advantages such as easy film formation / manufacturing and a high degree of freedom in material selection / combination have become mainstream.

  As the layer structure of the organic photoreceptor, a so-called single-layer photoreceptor in which a charge generation material is dispersed in a binder resin, and a laminate photoreceptor in which a charge generation layer and a charge transfer layer are laminated are known. Type photoreceptors can produce highly sensitive and stable photoreceptors by combining high-efficiency charge-generating substances and charge-transporting substances in separate layers. For many reasons, it is used a lot.

  The sensitivity of the electrophotographic photosensitive member when an organic charge generating material is used varies depending on the type of the charge generating material and also varies depending on the wavelength of exposure light. As a charge generating substance having sensitivity to light having a long wavelength of 600 to 800 nm, phthalocyanine compounds have attracted attention. Researches on metal-containing phthalocyanines such as magnesium phthalocyanine and oxytitanium phthalocyanine, or metal-free phthalocyanines have been conducted energetically.

For example, Patent Document 1 discloses many organic charge transport materials such as poly-N-vinylcarbazole, triphenylamine compounds, and benzidine compounds. The tertiary amine compound having been reported has been reported as a charge transport material that can satisfy the basic characteristics required for a photoreceptor.

JP-A-3-285960

  As described above, a large number of charge generation materials and charge transport materials are known, but if a charge generation material known to have high performance in a dark cloud and a charge transport material are used in combination, it is excellent. It is not possible to provide an electrophotographic photosensitive member that has the characteristics of an electrophotographic photosensitive member and that can provide a desired high-quality image when used in an image forming apparatus. In particular, in recent years, many studies have been made to improve the image quality and speed of image forming apparatuses, and accordingly, electrophotographic photosensitive members effective for increasing the image quality and speed have been widely desired.

The present invention has been made in view of the above problems. That is, an object of the present invention is to provide an electrophotographic photosensitive member suitable for a high-quality and high-speed image forming apparatus, and to provide a process cartridge and an image forming apparatus using the electrophotographic photosensitive member. is there.

As a result of intensive studies to solve the above problems, the present inventors have used a metal-containing phthalocyanine as a charge generation material and combined with a charge transport material having a naphthyl group to have high sensitivity and low residual potential electrical characteristics. In addition, the inventors have found that it is possible to obtain an electrophotographic photoreceptor capable of forming a high-quality image, and have completed the present invention.
That is, the first gist of the present invention is an electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the photosensitive layer comprises a tertiary naphthylamine compound represented by the following general formula (1) and a metal phthalocyanine. It exists in the electrophotographic photoreceptor characterized by containing.

(In the general formula (1), Ar ₁ and Ar ₂ represent an aryl group having 10 or less carbon atoms constituting the aromatic ring, R represents a substituent other than hydrogen, and the total number of all carbon atoms of Rn is 5 And n represents an integer of 0 to 7. The aryl group may have a substituent.)
The second gist of the present invention resides in at least an electrophotographic photosensitive member according to the present invention and an electrophotographic process cartridge including the photosensitive member and configured to be detachable from an image forming apparatus. The third gist of the present invention includes an electrophotographic photosensitive member according to the present invention, 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 An image forming apparatus comprising: at least one developing unit that develops an electrostatic latent image formed on the electrophotographic photosensitive member.

  The electrophotographic photoreceptor of the present invention has high sensitivity and low residual potential electrical characteristics when a metal-containing phthalocyanine and a tertiary naphthylamine compound having a specific structure are used as a charge transport material, and can form a high-quality image. It is possible to provide a possible electrophotographic photosensitive member, an electrophotographic process cartridge including the electrophotographic photosensitive member, and an image forming apparatus including the electrophotographic photosensitive member.

It is a figure which shows an example of the image forming apparatus of this invention.

1. Drum-shaped photoconductor Axis 3. Charging means 4. 4. Exposure unit Developing means 6. Transfer means 7. Transcript 8 Fixing means 9. Cleaning means 10. Static elimination means

Hereinafter, the embodiments of the present invention will be described in detail. However, the present invention is not limited to the following descriptions, and can be appropriately modified and implemented without departing from the gist of the present invention.
The electrophotographic photoreceptor of the present invention requires that a metal-containing phthalocyanine and a tertiary naphthylamine compound having a specific structure are used in combination in the photosensitive layer.

<Metal-containing phthalocyanine>
The metal-containing phthalocyanine is a compound containing a metal atom at the center of the phthalocyanine ring represented by the following formula (X).

  Specific examples of metal-containing phthalocyanines include metals such as copper, indium, gallium, tin, titanium, zinc, vanadium, silicon, germanium, or their oxides, halides, hydroxides, alkoxides, and the like. Various crystal forms of phthalocyanines are used. In particular, titanyl phthalocyanines (also known as oxytitanium phthalocyanine) such as A type (also known as β type), B type (also known as α type), D type (also known as Y type), vanadyl phthalocyanine, chloroindium phthalocyanine, which are highly sensitive crystal types Chlorogallium phthalocyanine such as type II, hydroxygallium phthalocyanine such as type V, μ-oxo-gallium phthalocyanine dimer such as type G and I, and μ-oxo-aluminum phthalocyanine dimer such as type II are suitable. is there. 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 dimer and the like are particularly preferable. In particular, oxytitanium phthalocyanine preferably has a clear diffraction peak mainly at a Bragg angle (2θ ± 0.2 °) of 27.2 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray.

  Further, the oxytitanium phthalocyanine preferably has a clear diffraction peak at a Bragg angle (2θ ± 0.2 °) of 9.0 ° to 9.7 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray. In view of the characteristics of the electrophotographic photosensitive member, main diffraction peaks at 9.6 °, 24.1 °, 27.2 °, or 9.5 °, 9.7 °, 24.1 °, and 27.2 ° are obtained. From the viewpoint of stability at the time of dispersion, it preferably has no peak at around 26.2 °. Among the oxytitanium phthalocyanines mentioned above, 7.3 °, 9.6 °, 11.6 °, 14.2 °, 18.0 °, 24.1 ° and 27.2 °, or 7.3 °, More preferably, it has main diffraction peaks at 9.5 °, 9.7 °, 11.6 °, 14.2 °, 18.0 °, 24.2 ° and 27.2 °.

The powder X-ray diffraction spectrum by CuKα characteristic X-ray in the present invention is measured based on the following method.
<Powder XRD measurement conditions>
As a measuring apparatus for measuring the X-ray diffraction spectrum of the powder, PW1700 manufactured by PANalytical, which is a powder X-ray diffractometer of a concentrated optical system using CuKα rays as a radiation source, was used.
Measurement conditions are: X-ray output 40 kV, 30 mA, scanning range (2θ) 3-40 °, scanning step width 0.05 °, scanning speed 3.0 ° / min, divergence slit 1.0 °, scattering slit 1.0 The light receiving slit was 0.2 mm.

In the oxytitanium phthalocyanine, the chlorine content in the crystal is preferably 1.5% by mass or less. The chlorine content is determined from elemental analysis.
In the oxytitanium phthalocyanine crystal, the ratio of the chlorinated oxytitanium phthalocyanine represented by the following formula (3) is higher than the unsubstituted oxytitanium phthalocyanine represented by the following formula (4). The ratio is 0.070 or less. The mass spectral intensity ratio is preferably 0.060 or less, more preferably 0.055 or less. In the production, when the dry milling method is used for amorphization, 0.02 or more is preferable, and when the acid paste method is used for amorphization, 0.03 or less is preferable. The amount of chlorine substitution is measured based on the method disclosed in JP-A No. 2001-115054.

  Precursor of oxytitanium phthalocyanine having a clear diffraction peak mainly at Bragg angle (2θ ± 0.2 °) of 27.2 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray, which is a metal-containing phthalocyanine suitable for the present invention. As a method for adjusting the low crystalline phthalocyanine and amorphous phthalocyanine to be a body, a known adjustment method such as a chemical treatment method such as an acid paste method or an acid slurry method, or a mechanical treatment method such as grinding or grinding is used. However, since a more uniform amorphous phthalocyanine or low crystalline phthalocyanine can be obtained, a chemical treatment method is preferable, and an acid paste method is more preferable.

  Specific examples of the chemical treatment include an acid pasting method in which oxytitanium phthalocyanine is dissolved in concentrated sulfuric acid, an acid slurry method (sulfate method) that is dispersed in sulfuric acid, dichlorotitanium phthalocyanine and phenol. Examples of the chemical treatment method include a method of obtaining oxytitanium phthalocyanine by adding alcohol and then removing it, and the acid paste method is more preferable for obtaining a more stable amorphous and low crystalline oxytitanium phthalocyanine.

The acid paste method and the acid slurry method are solutions in which a pigment is dissolved or suspended or dispersed in a strong acid, and the prepared solution is uniformly mixed with a strong acid in a medium in which the pigment hardly dissolves (for example, In the case of oxytitanium phthalocyanine, it is released into water, alcohols such as methanol, ethanol, and propanol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol diethyl ether, ethers such as tetrahydrofuran, etc.) and re-pigmented to modify the pigment. It is a way to quality.

  Strong acids such as concentrated sulfuric acid, organic sulfonic acid, organic phosphonic acid, and trihalogenated acetic acid are used in the acid slurry method and the acid paste method. These strong acids can be used as a strong acid alone, a mixture of strong acids or a combination of a strong acid and an organic solvent. The kind of strong acid is preferably trihalogenated acetic acid or concentrated sulfuric acid in consideration of the solubility of oxytitanyl phthalocyanine, and concentrated sulfuric acid is more preferable in consideration of production cost.

The content of concentrated sulfuric acid is preferably 90% or more when considering the solubility of oxytitanium phthalocyanine, and more preferably 95% or more because the production efficiency decreases if the content of concentrated sulfuric acid is low. Concentrated sulfuric acid.
The temperature at which oxytitanyl phthalocyanine is dissolved in a strong acid can be dissolved under the temperature conditions described in known literature. However, if the temperature is too high, the phthalocyanine ring opens and decomposes. The temperature is preferably 0 ° C. or lower, and more preferably 0 ° C. or lower in consideration of the influence on the obtained electrophotographic photosensitive member.

  The amount of strong acid to be used can be used in any amount, but if it is too small, the solubility of oxytitanyl phthalocyanine will deteriorate, so that 5 parts by weight or more in 1% by weight of oxytitanyl phthalocyanine in the solution. If the solid content concentration is too high, the stirring efficiency is lowered, so that it is preferably 15 parts by weight or more, more preferably 20 parts by weight or more. Further, if the amount of strong acid used is too large, the amount of waste acid increases, so that it is preferably 100 parts by weight or less, and more preferably 50 parts by weight or less in view of production efficiency.

  Examples of the medium for releasing the obtained acid solution of oxytitanium phthalocyanine include water, alcohols such as methanol, ethanol, 1-propanol and 2-propanol, polyhydric alcohols such as ethylene glycol and glycerin, tetrahydrofuran, dioxane and dioxolane. In addition, cyclic ethers such as tetrahydropyran, and chain-ethers such as ethylene glycol monomethyl ether and ethylene glycol diethyl ether can be used. Similarly to known methods, the release medium can be used alone or in combination of two or more. May be used. Depending on the type of medium used, the particle shape, crystal state, etc. when re-pigmented change, and this history affects the electrophotographic photoreceptor characteristics of the final crystal obtained later. Therefore, water, methanol, ethanol are preferable. Lower alcohols such as 1-propanol and 2-propanol are preferable, and water is more preferable in terms of productivity and cost.

  A concentrated sulfuric acid solution of oxytitanyl phthalocyanine is released into the release medium, and the re-pigmented oxytitanium phthalocyanine is filtered off as a wet cake, but this wet cake is concentrated sulfuric acid present in the release medium. Since it contains a large amount of impurities such as ions, it is washed with a washing medium after being re-pigmented. The cleaning medium is an aqueous solution of sodium hydroxide, aqueous potassium hydroxide, aqueous sodium hydrogen carbonate, aqueous sodium carbonate, aqueous potassium carbonate, aqueous sodium acetate, aqueous ammonia, etc., acidic such as dilute hydrochloric acid, dilute nitric acid, dilute acetic acid, etc. Examples include aqueous solutions and water such as ion-exchanged water, but ionic substances remaining in the pigment often have adverse effects on the characteristics of electrophotographic photoreceptors, so ionic substances such as ion-exchanged water were removed. Water is preferred.

Usually, the oxytitanium phthalocyanine obtained from the acid paste method and the acid slurry method is amorphous with no clear diffraction peak or has a peak, but its intensity is very weak and low with a peak having a very large half width. It is crystalline.
Usually, CuKα that can be suitably used in the electrophotographic photoreceptor of the present invention by bringing amorphous oxytitanium phthalocyanine obtained by the acid paste method or acid slurry method or low crystalline oxytitanium phthalocyanine into contact with an organic solvent. Bragg angle (2θ ± 0.2 °) 9.6 °, 24.1 °, 27.2 ° or 9.5 °, 9.7 °, 24.1 ° for characteristic X-rays (wavelength 1.541 mm) 27.2, an oxytitanium phthalocyanine having a main diffraction peak at 27.2 can be obtained.

Usually, the contact with the organic solvent is carried out in the presence of water. Even if the water contained in the water-containing cake obtained by the acid paste method or the acid slurry method is used, the water-containing cake obtained after the acid paste method and the acid slurry method is once dried, and water is newly added at the time of crystal conversion. It may be used additionally, but if it is dried, the affinity between the pigment and water will decrease, so it is contained in the hydrous cake obtained by the acid paste method and acid slurry method without drying. It is preferable to perform using.

  As a solvent that can be used for crystal conversion, any of a solvent compatible with water and a solvent incompatible with water can be used. Preferable examples of the solvent compatible with water include cyclic ethers such as tetrahydrofuran, 1,4-dioxane, 1,3-dioxolane. In addition, preferable examples of solvents incompatible with water include aromatic hydrocarbon solvents such as toluene, naphthalene, and methylnaphthalene, chlorotoluene, o-dichlorotoluene, dichlorofluorobenzene, 1,2-dichloroethane, and the like. Examples include halogenated solvents, substituted aromatic solvents such as nitrobenzene, 1,2-methylenedioxybenzene, and acetophenone. Among them, cyclic ethers, chlorotoluene, halogenated hydrocarbon solvents, and aromatic hydrocarbon solvents were obtained. This is preferable because the electrophotographic characteristics of the crystal are good, and tetrahydrofuran, o-dichlorobenzene, 1,2-dichlorotoluene, dichlorofluorobenzene, toluene, and naphthalene are more preferable in terms of stability during dispersion of the obtained crystal. .

The crystal obtained after the crystal conversion is subjected to a drying step, and the drying method can be dried by a known method such as air drying, heat drying, vacuum drying, freeze drying and the like.
The particle diameter of these oxytitanium phthalocyanines varies greatly depending on the production method and the crystal conversion method, but considering the dispersibility, the primary particle diameter is preferably 500 nm or less, and preferably 300 nm or less from the viewpoint of coating film formability. .

<Tertiary naphthylamine compound>
A tertiary naphthylamine compound having a specific structure is used for the electrophotographic photoreceptor of the present invention. The mechanism by which naphthylamine compounds having the structure described below contribute to the high sensitivity and low residual potential characteristics of the photoreceptor is not clear, but the energy levels of the frontier orbitals of the charge generation material and charge transport material are compatible. Is presumed to be one of the causes.

  A tertiary naphthylamine compound having the structure of the following general formula (1) is used for the electrophotographic photoreceptor in the present invention.

(In the general formula (1), Ar ₁ and Ar ₂ represent an aryl group having 10 or less carbon atoms constituting the aromatic ring, R represents a substituent other than hydrogen, and n represents an integer of 0 to 7. The aryl group may have a substituent.)
Ar ₁ and Ar ₂ represent an aryl group having 10 or less carbon atoms constituting the aromatic ring. Here, the aryl group may have a substituent. Examples of the aryl group represented by Ar ₁ and Ar ₂ include a phenyl group and a naphthyl group. However, when the conjugated system is highly expanded by a substituent such as a condensed polycycle, the interaction between molecules becomes stronger, and the reaction to the solvent Since solubility decreases, at least one is preferably a phenyl group, and more preferably both Ar ₁ and Ar ₂ are phenyl groups. The substituents that Ar ₁ and Ar ₂ may have include a hydrogen atom, a halogen atom, an alkyl group, a halogenated alkyl group, an aryl group, a halogenated aryl group, a heterocyclic group, a cyano group, a hydroxyl group, and a nitro group. Group, carboxyl group, sulfo group, amino group, alkoxy group, aryloxy group, alkylthio group, or arylthio group, etc., but durability against repeated use when used as an electrophotographic photoreceptor, durability against ozone and Considering having the characteristics of low residual potential, it has a lower alkyl group having 5 or less carbon atoms such as a methyl group, an ethyl group or a 2-propyl group, an alkoxy group having 5 or less carbon atoms such as a methoxy group or an ethoxy group. Is preferred. In particular, considering the mobility as a charge transport material, both Ar ₁ and Ar ₂ are more preferably phenyl groups having a substituent at the para position substituted by a nitrogen atom, and more preferably Ar ₁ and Ar ₂ are More preferably, both are phenyl groups having a lower alkyl group having 5 or less carbon atoms or an alkoxy group having 5 or less carbon atoms at the para position substituted by a nitrogen atom, and more preferably both Ar ₁ and Ar ₂ are nitrogen atoms. It is preferably a phenyl group having a lower alkyl group having 3 or less carbon atoms or an alkoxy group having 3 or less carbon atoms in the para position substituted by the atom. Among the aryl groups and unsubstituted aryl groups having substituents, 4-methylphenyl group or 4-methoxyphenyl group is more suitable when considering the versatility of the reagent and the performance when used as an electrophotographic photoreceptor. preferable.

R is, for example, a halogen atom, alkyl group, halogenated alkyl group, aryl group, halogenated aryl group, heterocyclic group, cyano group, hydroxyl group, nitro group, carboxyl group, sulfo group, amino group, alkoxy group, aryloxy Group, alkylthio group, arylthio group, etc., considering that it has durability against repeated use when used as an electrophotographic photosensitive member, durability against ozone, and low residual potential characteristics, an alkyl group or an alkoxy group It is particularly preferably an alkyl group having 5 or less carbon atoms such as a methyl group, an ethyl group or a 2-propyl group, or an alkoxy group having 5 or less carbon atoms such as a methoxy group or an ethoxy group. Among these, considering mobility as a charge transport material, R is most preferably a methyl group or a methoxy group.

n represents the substitution number of R directly bonded to the naphthyl group, and represents an integer of 0 to 7. From the viewpoint of versatility of the raw material, 0 to 5 is preferable, 0 to 2 is particularly preferable, and 0 or 1 is most preferable.
When n ≧ 2, they may be bonded to each other to form a ring structure. At this time, the number of all carbon atoms of R to be bonded is preferably 5 or less, and particularly preferably 3 or less, for the convenience of synthesis.
The suitable structure of the tertiary naphthylamine compound which can be used for this invention below is illustrated. 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.

<Electrophotographic photoreceptor>
Hereinafter, the electrophotographic photoreceptor of the present invention will be described in detail.
As the conductive support used for the photoreceptor, 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 to impart conductivity. A resin material, a resin, glass, paper, or the like on which a conductive material such as aluminum, nickel, or ITO (indium tin oxide) is deposited or applied on the surface is mainly used. As a form, a drum shape, a sheet shape, a belt shape or the like is used. For conductive support of metallic materials, for control of conductivity and surface properties, and for defect coating. A conductive material having an appropriate resistance value may be applied.

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, it is formed by anodizing in an acidic bath such as chromic acid, sulfuric acid, oxalic acid, boric acid, sulfamic acid, etc., but anodizing in sulfuric acid gives better results. In the case of anodic oxidation in sulfuric acid, the sulfuric acid concentration is 100-300 g / l, the dissolved aluminum concentration is 2-15 g / l, the liquid temperature is 15-30 ° C., the electrolysis voltage is 10-20 V, and the current density is 0.5-. it is preferably in the range of 2A / dm ^2, but 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 normal method. For example, the low-temperature sealing treatment is performed by immersion in an aqueous solution containing nickel fluoride as a main component, or the high-temperature sealing is performed by immersion in an aqueous solution containing nickel acetate as a main component. It is preferable that the treatment is performed.
The concentration of the nickel fluoride aqueous solution used in the case of the low-temperature sealing treatment can be selected as appropriate, but more preferable results are obtained when it is used in the range of 3-6 g / l. In order to smoothly proceed with the sealing treatment, the treatment temperature is 25-40 ° C., preferably 30-35 ° C., and the pH of the nickel fluoride aqueous solution is 4.5-6.5, preferably It is better to process in the range of 5.5-6.0. 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 film properties, cobalt fluoride, cobalt acetate, nickel sulfate, a surfactant and 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, an aqueous solution of a metal salt such as nickel acetate, cobalt acetate, lead acetate, nickel acetate-cobalt, barium nitrate can be used, and it is particularly preferable to use nickel acetate. . The concentration in the case of using an aqueous nickel acetate solution is preferably in the range of 5-20 g / l. The treatment temperature is 80-100 ° C., preferably 90-98 ° C., and the pH of the nickel acetate aqueous solution is preferably 5.0-6.0. Here, ammonia water, 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. In particular, when using a non-cutting aluminum substrate such as drawing, impact processing, ironing, etc., it is preferable because the treatment eliminates dirt, foreign matter, and other foreign matters, small scratches, etc., and a uniform and clean substrate can be obtained. .

An undercoat layer may be provided between the conductive support and the photosensitive layer described later for improving adhesion and blocking properties. As the undercoat layer, a resin, a resin in which particles such as a metal oxide are dispersed, or the like is used.
Examples of the metal oxide particles used for the undercoat layer include metal oxide particles containing one metal element such as titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, zinc oxide, iron oxide, calcium titanate, Examples thereof include metal oxide particles containing a plurality of metal elements such as strontium titanate and barium titanate. Only one type of particles may be used, or a plurality of types of particles may be mixed and used. Among these metal particles, titanium oxide and aluminum oxide are preferable, and titanium oxide is particularly preferable. The surface of the titanium oxide particles may be treated with 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 silicone. As the crystal form of the titanium oxide particles, any of rutile, anatase, brookite, and amorphous can be used. Moreover, the thing of a several crystal state may contain.

Various particle diameters of the metal oxide particles can be used. Among these, from the viewpoint of characteristics and liquid stability, the average primary particle diameter is preferably 10 nm or more and 100 nm or less, and particularly preferably 10 nm. It is 50 nm or less.
The undercoat layer is preferably formed in a form in which the metal oxide particles are dispersed in a binder resin. The binder resin used for the undercoat layer is epoxy resin, polyethylene resin, polypropylene resin, acrylic resin, methacrylic resin, polyamide resin, vinyl chloride resin, vinyl acetate resin, phenol resin, polycarbonate resin, polyurethane resin, polyimide resin, chloride resin. Vinylidene resin, polyvinyl acetal resin, vinyl chloride-vinyl acetate copolymer, polyvinyl alcohol resin, polyurethane resin, polyacrylic acid resin, polyacrylamide resin, polyvinyl pyrrolidone resin, polyvinyl pyridine resin, water-soluble polyester resin, cellulose such as nitrocellulose Ester resin, cellulose ether resin, casein, gelatin, polyglutamic acid, starch, starch acetate, amino starch, zirconium chelate compound, zirconi Organic zirconium compounds of the arm alkoxide compounds, titanyl chelate compounds, organic titanyl compounds such as titanyl alkoxide compound, may be a known binder resin such as a silane coupling agent. These can be used alone or in a cured form together with a curing agent. Among these, alcohol-soluble copolymerized polyamide, modified polyamide, and the like are preferable because they exhibit good dispersibility and coatability.

The addition ratio of the inorganic particles to the binder resin used in the undercoat layer can be arbitrarily selected, but it is preferably used in the range of 10 wt% to 500 wt% in terms of the stability of the dispersion and the coating surface.
The thickness of the undercoat layer can be arbitrarily selected, but it is used within the range of 0.01-30 μm, preferably 0.1-20 μm, from the photoreceptor characteristics and coating properties. For the purpose of preventing defects, pigment particles, resin particles, and the like may be included and used.

  The photosensitive layer formed on the conductive support may have a single layer structure in which the charge generation material and the charge transport material are present in the same layer and are dispersed in the binder resin, or the charge generation material may be Any of a layered structure of a function-separated type photoreceptor in which a charge generation layer dispersed in a binder and a charge transport material are separated into a charge transport layer dispersed in a binder resin may be used. When the photosensitive layer has a laminated structure, the charge generation layer is composed of a charge generation material containing at least one metal-containing phthalocyanine and a binder resin.

The charge generation layer in the function-separated type photoreceptor is prepared by dispersing a charge generation material containing at least one metal-containing phthalocyanine in a solution obtained by dissolving a binder resin in an organic solvent. It is formed by coating on a conductive support and binding fine particles of a charge generating material and various binder resins.
As the charge generation material, metal-containing phthalocyanine may be used alone, or may be used in a mixed state with several dyes and pigments.

Examples of dyes and pigments used in a mixed state with metal-containing phthalocyanines include phthalocyanine pigments, azo pigments, dithioketopyrrolopyrrole pigments, squalene (squarylium pigments), quinacridone pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, anthanthrone pigments, benz Examples thereof include imidazole pigments.
As dyes and pigments used in the mixed state, phthalocyanine pigments and azo pigments are preferably used from the viewpoint of photosensitivity.

  Examples of the binder resin used for the charge generation layer in the function-separated photoreceptor include polyvinyl butyral resin, polyvinyl formal resin, partially acetalized polyvinyl butyral resin in which a part of butyral is modified with formal, acetal, etc. Polyvinyl acetal resin, polyarylate resin, polycarbonate resin, polyester resin, modified ether polyester resin, phenoxy resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl acetate resin, polystyrene resin, acrylic resin, methacrylic resin, polyacrylamide Resin, polyamide resin, polyvinyl pyridine resin, cellulose resin, polyurethane resin, epoxy resin, silicone resin, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, casein, chloride Vinyl chloride-vinyl acetate, such as nyl-vinyl acetate copolymer, hydroxy-modified vinyl chloride-vinyl acetate copolymer, carboxyl-modified vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer Copolymer, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, styrene-alkyd resin, silicon-alkyd resin, phenol-formaldehyde resin and other insulating resins, poly-N-vinylcarbazole, polyvinylanthracene, It can be selected from organic photoconductive polymers such as polyvinyl perylene, but is not limited to these polymers. These binder resins may be used alone or in combination of two or more.

  Solvents and dispersion media used to dissolve the binder resin and prepare the coating solution include, for example, saturated aliphatic solvents such as pentane, hexane, octane, and nonane, aromatic solvents such as toluene, xylene, and anisole, chlorobenzene Halogenated aromatic solvents such as dichlorobenzene and chloronaphthalene, amide solvents such as dimethylformamide and N-methyl-2-pyrrolidone, alcohol solvents such as methanol, ethanol, isopropanol, n-butanol and benzyl alcohol, glycerin , Aliphatic polyhydric alcohols such as polyethylene glycol, chain solvents such as acetone, cyclohexanone, methyl ethyl ketone, and cyclic ketone solvents, ester solvents such as methyl formate, ethyl acetate, n-butyl acetate, methylene chloride, chloroform, 1 , 2-Dichloroeta Halogenated hydrocarbon solvents such as diethyl ether, dimethoxyethane, tetrahydrofuran, 1,4-dioxane, methyl cellosolve, ethyl cellosolve, etc., and cyclic ether solvents, acetonitrile, dimethyl sulfoxide, sulfolane, hexamethyl Examples include aprotic polar solvents such as phosphoric acid triamide, n-butylamine, isopropanolamine, diethylamine, triethanolamine, nitrogen-containing compounds such as ethylenediamine, triethylenediamine, and triethylamine, mineral oil such as ligroin, and water. Those which do not dissolve the pulling layer are preferably used. These can be used alone or in combination of two or more.

  In the charge generation layer of the function-separated type photoreceptor, the compounding ratio (weight) of the binder resin and the charge generation material is 10 to 1000 parts by weight, preferably 30 to 500 parts by weight with respect to 100 parts by weight of the binder resin. The film thickness is usually 0.1 μm to 10 μm, preferably 0.15 μm to 0.6 μm. If the ratio of the charge generation material is too high, the stability of the coating solution is lowered due to problems such as aggregation of the charge generation material. On the other hand, if it is too low, the sensitivity as a photoreceptor is reduced. Things are preferable. As a method for dispersing the charge generation material, a known dispersion method such as a ball mill dispersion method, an attritor dispersion method, or a sand mill dispersion method can be used. In this case, it is effective to refine the particles to a particle size of 0.5 μm or less, preferably 0.3 μm or less, more preferably 0.15 μm or less.

  In forming a charge transport layer of a function-separated type photoreceptor having a charge generation layer and a charge transport layer and a photosensitive layer of a single layer type photoreceptor, a binder resin is used to ensure film strength. In the case of the charge transport layer of the functional separation type photoconductor, a coating solution obtained by dissolving or dispersing the charge transport material and various binder resins in a solvent, or in the case of a single layer type photoconductor, the charge generation material and the charge transport It can be obtained by applying and drying a coating solution obtained by dissolving or dispersing the substance and various binder resins in a solvent. Examples of the binder resin include polymers and copolymers of vinyl compounds such as butadiene resin, styrene resin, vinyl acetate resin, vinyl chloride resin, acrylic ester resin, methacrylic ester resin, vinyl alcohol resin, ethyl vinyl ether, and polyvinyl butyral. Resin, polyvinyl formal resin, partially modified polyvinyl acetal, polycarbonate resin, polyester resin, polyarylate resin, polyamide resin, polyurethane resin, cellulose ester resin, phenoxy resin, silicone resin, silicon-alkyd resin, poly-N-vinylcarbazole resin, etc. Is given. These resins may be modified with a silicon reagent or the like. Of the binder resins, polycarbonate resins and polyarylate resins are particularly preferable.

Among polycarbonate resins and polyarylate resins, bisphenols having the following structural formulas, polycarbonate resins containing polyphenol components, and polyarylate resins are preferable from the viewpoint of sensitivity and residual potential, and polycarbonate resins are more preferable from the viewpoint of mobility. preferable.
Examples of the structure of bisphenol and biphenol that can be suitably used for the polycarbonate resin 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.

  These can also be used by crosslinking with an appropriate curing agent by heat, light or the like. Also, two or more kinds of binder resins can be blended and used. The viscosity average molecular weight of the polycarbonate resin and the polyarylate resin is not particularly limited, but is usually 10,000 or more, preferably 15,000 or more, more preferably 20,000 or more, provided that it is usually 300,000 or less. Preferably it is 200,000 or less, More preferably, it is 100,000 or less. If the viscosity average molecular weight is excessively small, the mechanical strength of the photosensitive layer is lowered, which is not practical. On the other hand, if the viscosity average molecular weight is excessively large, it is difficult to apply and form the photosensitive layer to an appropriate film thickness.

  As the charge transport material, the tertiary naphthylamine compound is used. The tertiary naphthylamine compound may be used alone or in combination with other charge transport materials. The charge transporting substance used in combination is not particularly limited as long as it is a known substance. For example, aromatic nitro compounds such as 2,4,7-trinitrofluorenone, and cyano compounds such as tetracyanoquinodimethane , Electron withdrawing substances such as quinone compounds such as diphenoquinone, carbazole derivatives, indole derivatives, imidazole derivatives, oxazole derivatives, pyrazole derivatives, thiadiazole derivatives, heterocyclic compounds such as benzofuran derivatives, aniline derivatives, hydrazone derivatives, aromatic amine derivatives, Examples thereof include electron donating substances such as stilbene derivatives, butadiene derivatives, enamine derivatives and those obtained by bonding a plurality of these compounds, or polymers having a group consisting of these compounds in the main chain or side chain. Among these, carbazole derivatives, aromatic amine derivatives, stilbene derivatives, butadiene derivatives, enamine derivatives, and those in which a plurality of these compounds are bonded are preferable.

  The ratio of the binder resin to the charge transport material is preferably 20 parts by weight or more with respect to 100 parts by weight of the binder resin for both single layer type and multilayer type, and preferably 30 parts by weight or more from the viewpoint of reducing the residual potential. From the viewpoint of stability and charge mobility, 40 parts by weight is more preferable. On the other hand, from the viewpoint of thermal stability of the photosensitive layer, it is usually 150 parts by weight or less, preferably 120 parts by weight or less from the viewpoint of compatibility between the charge transport material and the binder resin, and from the viewpoint of printing durability. The amount is more preferably 100 parts by weight or less, and particularly preferably 80 parts by weight or less from the viewpoint of scratch resistance.

In the case of a laminated type photoreceptor, the film thickness is generally used in the range of 5-50 μm, but is preferably 10-45 μm from the viewpoint of long life and image stability, and 10-30 μm from the viewpoint of high resolution. More preferred.
The photosensitive layer has well-known antioxidants, plasticizers, ultraviolet absorbers, electron-withdrawing compounds to improve film-forming properties, flexibility, coating properties, stain resistance, gas resistance, light resistance, etc. In addition, additives such as a leveling agent and a visible light shielding agent may be contained.

  In the case of a single layer type photoreceptor, the above-mentioned metal-containing phthalocyanine is further dispersed in the charge transport medium having the blending ratio as described above. In this case, the particle size of the metal-containing phthalocyanine needs to be sufficiently small, preferably 1 μm or less, more preferably 0.5 μm or less. If the amount of the metal-containing phthalocyanine dispersed in the photosensitive layer is too small, sufficient sensitivity cannot be obtained. If the amount is too large, there is a problem that the charging property is lowered and the sensitivity is lowered. For example, the amount is preferably 0.1 to 50% by weight. It is used in the range, preferably in the range of 1 to 20% by weight. The film thickness in the case of a single layer type photoreceptor is usually 5 to 100 μm, preferably 10 to 50 μm.

In a laminated type or single-layer type photoreceptor, a protective layer is provided on the outermost layer for the purpose of preventing the photosensitive layer from being worn and preventing or reducing the deterioration of the photosensitive layer due to discharge substances generated from a charger or the like. May be. The protective layer is formed by containing a conductive material in an appropriate binder resin, or charge transport ability such as a triphenylamine skeleton as described in JP-A-9-190004 and JP-A-10-252377. The copolymer using the compound which has can be used. Examples of the conductive material include aromatic amino compounds such as TPD (N, N′-diphenyl-N, N′-bis- (m-tolyl) benzidine), antimony oxide, indium oxide, tin oxide, titanium oxide, and tin oxide. -Metal oxides such as antimony oxide, aluminum oxide, and zinc oxide can be used, but are not limited thereto. As the binder resin used for the protective layer, known resins such as polyamide resin, polyurethane resin, polyester resin, epoxy resin, polyketone resin, polycarbonate resin, polyvinyl ketone resin, polystyrene resin, polyacrylamide resin, and siloxane resin can be used. Also, a skeleton having a charge transporting ability such as a triphenylamine skeleton as described in JP-A-9-190004 and a copolymer of the above resin can be used. The protective layer is preferably configured to have an electric resistance of 10 ⁹ -10 ¹⁴ Ω · cm. Blur the electric resistance becomes a 10 ¹⁴ Ω · cm from as high as many image residual potential of increased fog, whereas if lower than 10 ⁹ Ω · cm image, decrease in resolution occurs. In addition, the protective layer must be configured so as not to substantially impede transmission of light irradiated for image exposure.

In addition, the surface layer contains fluorine resin, silicone resin, polyethylene resin, etc. for the purpose of reducing frictional resistance and wear on the surface of the photoconductor and increasing the transfer efficiency of the toner from the photoconductor to the transfer belt and paper. May be. Moreover, the particle | grains which consist of these resin, and the particle | grains of an inorganic compound may be included.
The coating solution obtained by the above method is usually used in the range of 5 to 40% by weight in the solid content concentration in the case of a single layer type photoreceptor and a charge transport layer of a function separation type photoreceptor. It is preferably used in the range of 35% by weight. The viscosity of the coating solution is usually used in the range of 10 to 500 cps, but is preferably used in the range of 50 to 400 cps. In the case of the charge generation layer of the function-separated type photoreceptor, the solid content is usually used in the range of 0.1 to 15% by weight, but more preferably in the range of 1 to 10%. The viscosity of the coating solution is usually used in the range of 0.01 to 20 cps, but more preferably in the range of 0.1 to 10 cps.

Each layer constituting these photoconductors is formed by applying the coating solution obtained by the above-described method on a support using a known coating method, repeating the coating and drying process for each layer, and sequentially coating the layers. The
Examples of the application method of the coating liquid include dip coating, spray coating, spinner coating, bead coating, wire bar coating, blade coating, roller coating, air knife coating, and curtain coating. Other known coating methods can also be used.

The coating solution is preferably dried by touching at room temperature and then heating and drying in a temperature range of 30 to 200 ° C. for 1 minute to 2 hours with no air or air. The heating temperature may be constant or may be changed while drying.
<Toner>
When an image is formed using the electrophotographic photosensitive member of the present invention, a toner as a developer is used to develop a latent image. By using the toner as described above, the image forming apparatus of the present invention can form a high-quality image.

<Toner circularity>
The shape of the toner is such that the shape of each particle contained 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, and the developability is improved. It tends to be uniform, which is preferable for improving image quality. In particular, if the shape of the toner is a perfect spherical shape, the contact area with the electrophotographic photosensitive member may be reduced, the toner transfer rate may be increased, and the toner consumption may be reduced. . On the other hand, it is difficult to manufacture a perfect spherical toner, and the cost of the toner increases. Therefore, it is sufficient that the toner is close to a sphere under a certain condition, and it is not necessary to be a perfect sphere.

  Therefore, specifically, the toner has an average circularity measured by a flow particle image analyzer of usually 0.940 or more, preferably 0.945 or more, more preferably 0.950 or more, and still more preferably 0. .955 or more, particularly 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 0.998 or less, more preferably 0.995 or less from the viewpoint of ease of production.

The average circularity 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. The circularity [a] of the measured particles is obtained by the following formula (X).
Circularity a = L0 / L (X)
(In the formula (X), L0 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 circularity is an index of the degree of unevenness of the toner particles, and is 1.000 when the toner is perfectly spherical, 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 this 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 (microliter). The circularity distribution of particles having an equivalent circle diameter of 60 μm or more and less than 160 μm is measured.

<Toner type>
The toner is not limited as long as it has the above average circularity. Various types of toner are usually obtained depending on the production method, and any toner can be used.
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, and further, a so-called pulverized toner is spheroidized 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.
As a method for producing a toner by a so-called polymerization method, a direct toner is used by using a suspension polymerization method described in JP-B-36-10231, JP-A-59-53856, and JP-A-59-61842. To form a toner, or a dispersion polymerization method in which an aqueous organic solvent in which a polymer that is soluble in a monomer is insoluble is used, or a direct polymerization in the presence of a water-soluble polar polymerization initiator. The toner can be produced using an emulsion polymerization method represented by a soap-free polymerization method.

Examples of the polymerization toner include suspension polymerization toner and emulsion polymerization aggregation toner.
In order to improve the releasability, low-temperature fixability, high-temperature offset resistance, filming resistance, etc. of the toner, a method of incorporating a low softening point substance (so-called 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 large amount (5 to 30% by mass) of a low softening point substance. The polymer here is one of the materials constituting the toner. For example, in the case of a toner produced by an emulsion polymerization aggregation method described later, the polymer is obtained by polymerizing a polymerizable monomer.

As a method for obtaining a toner having a fine particle size distribution of 3 to 8 μm with a sharp particle size distribution that can control the average circularity of the toner to 0.940 or more, for example, suspension under normal pressure or under pressure is used. Examples thereof include a turbid polymerization method and an emulsion polymerization aggregation method.
When manufacturing toner using the suspension polymerization method, the specific method for embedding the low softening point material is to set the polarity of the material in the aqueous medium to be smaller than that of the main monomer. In addition, a toner having a so-called core / shell structure in which a low softening point substance is coated with an outer shell resin can be obtained by adding a small amount of a highly polar resin or monomer. Toner particle size distribution control and particle size control can be achieved by changing the type and amount of a poorly water-soluble inorganic salt or dispersant that acts as a protective colloid, as well as mechanical equipment conditions, such as rotor speed, number of passes, A predetermined toner can be obtained by controlling the stirring conditions such as the shape of the stirring blade, the container shape, or the solid content concentration in the aqueous solution.

As the outer shell resin of the toner used in the present invention, generally used styrene- (meth) acrylic copolymers, polyester resins, epoxy resins, and styrene-butadiene copolymers can be used. Those monomers are preferably used in a method of directly obtaining toner by a polymerization method.
Specifically, styrene monomers such as styrene, o (m-, p-)-methylstyrene, m (p-)-ethylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate, ( Meth) propyl acrylate, butyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (Meth) acrylic acid ester monomers such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate; ene monomers such as butadiene, isoprene, cyclohexene, (meth) acrylonitrile, and acrylamide Is preferably used.

  These monomers are used alone or generally so that the theoretical glass transition temperature (Tg) described in the publication polymer handbook 2nd edition III-P139-192 (John Wiley & Sons) is 40-75 ° C. It is used by mixing appropriately. When the theoretical glass transition temperature is less than 40 ° C., there are problems in terms of storage stability of the toner and durability of the developer. On the other hand, when it exceeds 75 ° C., the fixing point is increased. In some cases, the color toners are not sufficiently mixed, resulting in poor color reproducibility. Further, the transparency of the OHP image is remarkably lowered, which is not preferable from the viewpoint of high image quality.

  The molecular weight of the outer shell resin is measured by GPC (gel permeation chromatography). As a specific GPC measurement method, a toner is previously extracted with a toluene solvent using a Soxhlet extractor for 20 hours, and then toluene is distilled off with a rotary evaporator. Further, the low softening point substance is dissolved, but the shell resin is used. After washing thoroughly with an organic solvent that cannot be dissolved, such as chloroform, a sample obtained by filtering a solution soluble in THF (tetrahydrofuran) with a solvent-resistant membrane filter having a pore size of 0.3 μm was manufactured by Waters. Using 150C, the column configuration can be measured by using A-801, 802, 803, 804, 805, 806, and 807 manufactured by Showa Denko and using a standard polystyrene resin calibration curve to measure the molecular weight distribution.

The number average molecular weight (Mn) of the obtained resin component is 5,000 to 1,000,000, and the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 2 to 100. Is preferred for the present invention.
In the present invention, when a toner having a core / shell structure is produced, it is particularly preferable to add a polar resin in addition to the outer shell resin in order to encapsulate the low softening point substance with the outer shell resin. As the polar resin used in the present invention, a copolymer of styrene and (meth) acrylic acid, a maleic acid copolymer, a saturated polyester resin, and an epoxy resin are preferably used. The polar resin is particularly preferably one containing no unsaturated group capable of reacting with the shell resin or monomer in the molecule. If a polar resin having an unsaturated group is included, a crosslinking reaction occurs with the monomer that forms the shell resin layer. Particularly, as a full-color toner, it becomes extremely high molecular weight, which is disadvantageous for color mixing of four-color toners. It is not preferable.

In the present invention, an outermost shell resin layer may be provided by a polymerization method so as to overlap with the surface of the toner having an outer shell structure.
The glass transition temperature of the outermost shell resin layer is designed to be higher than the glass transition temperature of the outer shell resin layer in order to further improve the blocking resistance, and is further crosslinked to such an extent that the fixing property is not impaired. Is preferred. The outermost resin layer preferably contains a polar resin or a charge control agent for improving the chargeability.

Further, the method of providing the outermost shell resin layer is not particularly limited, and examples thereof include the following methods.
1. In the latter half of the polymerization reaction, or after completion, if necessary, a polar resin, a charge control agent, a crosslinking agent, etc. dissolved and dispersed in the reaction system are added and adsorbed onto the polymer particles, and a polymerization initiator is added to perform polymerization. How to do.
2. If necessary, emulsion-polymerized particles or soap-free polymerized particles consisting of monomers containing a polar resin, a charge control agent, a crosslinking agent, etc. are added to the reaction system and aggregated on the surface of the polymerized particles. How to fix.
3. A method in which emulsion-polymerized particles or soap-free polymerized particles comprising monomers containing a polar resin, a charge control agent, a crosslinking agent, etc. are mechanically fixed to the toner particle surface in a dry manner as required.

  As the colorant used in the present invention, carbon black, a magnetic material, and a black colorant that is toned in black using the following yellow / magenta / cyan colorant are used. As the yellow colorant, compounds represented by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 168, etc. are preferably used.

  As the magenta colorant, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds are used. Specifically, C.I. I. Pigmentlets 2,3,5,6,7,23,48; 2,48; 3,48; 4,57; 1,81; 1,144,146,166,169,177,184,185,202, 206, 220, 221, 254 are particularly preferred.

  As the cyan colorant used in the present invention, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds, and the like can be used. Specifically, C.I. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 15; 3, 15: 4, 60, 62, 66 and the like can be used particularly preferably. These colorants can be used alone or mixed and further used in the form of a solid solution.

In the case of a color toner, the colorant of the present invention is selected from the viewpoints of hue angle, saturation, brightness, weather resistance, OHP transparency, and dispersibility in the toner. The colorant is added in an amount of 1 to 20 parts by mass with respect to 100 parts by mass of the resin. When a magnetic material is used as the black colorant, 40 to 150 parts by mass are added to 100 parts by mass of the resin, unlike other colorants.
As the charge control agent used in the present invention, known ones can be used. In the case of a color toner, in particular, a charge control agent that is colorless and has a high toner charging speed and can stably maintain a constant charge amount. preferable. Further, when the direct polymerization method is used in the present invention, a charge control agent having no polymerization inhibition and no solubilized product in an aqueous system is particularly preferable.

  Specific examples of the negative compounds include salicylic acid, naphthoic acid, dicarboxylic acid metal compounds, sulfonic acid, polymer compounds having carboxylic acid in the side chain, boron compounds, urea compounds, silicon compounds, calixarene, and the like. As a positive system, a quaternary ammonium salt, a polymer compound having the quaternary ammonium salt in the side chain, a guanidine compound, an imidazole compound, and the like are preferably used. The charge control agent is preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the resin. However, the addition of a charge control agent is not essential in the present invention.

  When the direct polymerization method is used in the present invention, examples of the polymerization initiator include 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, , 1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azo polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, Peroxide polymerization initiators such as methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide are used.

The addition amount of the polymerization initiator varies depending on the target degree of polymerization, but generally 0.5 to 20% by mass is added to the monomer. The kind of the initiator is slightly different depending on the polymerization method, but can be used alone or mixed with reference to the 10-hour half-life temperature. In order to control the degree of polymerization, a known crosslinking agent, chain transfer agent, polymerization inhibitor and the like can be further added and used.
When suspension polymerization is used as a toner production method used in the present invention, as a dispersant to be used, for example, as an inorganic oxide, tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate , Magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina, magnetic substance, ferrite and the like. As the organic compound, for example, polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, sodium salt of ethyl cellulose C carboxymethyl cellulose, starch and the like are used by dispersing in an aqueous phase. These dispersants are preferably used in an amount of 0.2 to 10.0 parts by mass with respect to 100 parts by mass of the polymerizable monomer.

  Commercially available dispersants may be used as they are, but in order to obtain dispersed particles having a fine and uniform particle size, the inorganic compound can be produced in a dispersion medium under high-speed stirring. For example, in the case of tricalcium phosphate, a dispersant preferable for the suspension polymerization method can be obtained by mixing an aqueous sodium phosphate solution and an aqueous calcium chloride solution under high-speed stirring. Moreover, you may use together 0.001-0.1 mass part surfactant for refinement | miniaturization of these dispersing agents. Specifically, commercially available nonionic, anionic and cationic surfactants can be used, for example, sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, Calcium oleate is preferably used.

  When the direct polymerization method is used as the toner production method used in the present invention, the toner can be specifically produced by the following production method. Monomer composition in which a release agent, colorant, charge control agent, polymerization initiator and other additives consisting of a low softening substance are added to the monomer and dissolved or dispersed uniformly by a homogenizer, ultrasonic disperser, etc. The product is dispersed in an aqueous phase containing a dispersion stabilizer by a usual stirrer, homomixer, homogenizer or the like. Preferably, granulation is performed by adjusting the stirring speed and time so that droplets of the monomer composition have a desired toner particle size. Thereafter, stirring may be performed to such an extent that the particle state is maintained and the sedimentation of the particles is prevented by the action of the dispersion stabilizer. Polymerization is carried out at a polymerization temperature of 40 ° C. or higher, generally 50 to 90 ° C. In addition, the temperature may be raised in the latter half of the polymerization reaction, and for the purpose of improving durability characteristics, in order to remove unreacted polymerizable monomers, by-products, etc. The aqueous medium may be distilled off. After completion of the reaction, the produced toner particles are recovered by washing and filtration and dried. In the suspension polymerization method, it is usually preferable to use 300 to 3000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the monomer system.

Further, the toner in the present invention may be classified to control the particle size distribution, and a multi-division classifying device using inertial force is preferably used as the method. By using this apparatus, the toner having the particle size distribution of the present invention can be efficiently produced.
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 a colorant (pigment), wax, charge control agent, etc. are dispersed in a dispersion containing the polymer primary particles as necessary. 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 fine polymer 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 a 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 the 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 members 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 method for performing emulsion polymerization using wax as a seed to obtain polymer primary particles will be described.
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. And a chain transfer agent, a pH adjuster, a polymerization degree adjuster, an antifoaming agent, a protective colloid, an internal additive, and the like, if necessary, and polymerization is performed. 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, low molecular weight polyethylene, low molecular weight polypropylene, copolymer polyethylene and other olefin waxes; paraffin wax; alkyl group silicone wax; low molecular weight polytetrafluoroethylene and other fluororesin waxes; higher fatty acids such as stearic acid; eicosanol Long-chain aliphatic alcohols such as behenate behenate, montanate ester, stearic acid ester-based wax having a long-chain aliphatic group; distearyl ketone and other ketones having a long-chain alkyl group; 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; Ester and the like. Among them, those having at least one endothermic peak by differential thermal analysis (DSC) at 50 to 100 ° C. are 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 mold release effect can be obtained in a small amount. In particular, paraffin wax is preferred. 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, it is desirable that 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 wax is too small, the fixing temperature range may be insufficient. If the amount is too large, the apparatus member may be contaminated and 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 (a personal SC meter model SC72 and a 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 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.

  In addition, 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 alone or in combination of two or more in any combination and ratio.

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 preparing the wax fine particles, 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. If the blending amount of the acidic monomer or basic monomer is below the above range, the dispersion stability of the polymer primary particles may be deteriorated, and if 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 below 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 a chain transfer agent, a pH adjuster, a polymerization degree adjuster, and an antifoaming agent, as necessary, in addition to the polymerization initiator and the polymerizable monomer. 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 a ratio.

Any known chain transfer agent can be used. Specific examples include t-dodecyl mercaptan, 2-mercaptoethanol, diisopropylxanthogen,
Examples thereof include carbon tetrachloride and trichlorobromomethane. 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, any known protective colloid that can be used in this application can be used. Specific examples include partially or completely saponified polyvinyl alcohols such as polyvinyl alcohol, cellulose derivatives such as hydroxyethyl cellulose, and the like.

Examples of the internal additive include those for modifying the adhesiveness, cohesiveness, fluidity, chargeability, surface resistance and the like of toner such as silicone oil, silicone varnish, and fluorine oil.
(Vii. Polymer primary particles)
Polymer initiators, polymerizable monomers, and additives as necessary are mixed in a liquid medium containing wax fine particles, stirred, and polymerized to obtain polymer primary particles. 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, there are no restrictions on the method of mixing and stirring, and the method is 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. If the volume average particle size is too large, the particle size of the toner obtained by aggregation tends to be large, and the target particles It may be difficult to obtain a toner having a diameter. The volume average particle diameter can be 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, the above volume particle size is set as follows using an ultrafine particle size distribution measuring apparatus using a dynamic light scattering method (manufactured by Nikkiso Co., Ltd., UPA-EX150, hereinafter abbreviated as UPA-EX). To do.

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. The volume average particle diameter according to the present invention is measured by using the result of the volume particle size distribution as an arithmetic average value.

  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 it is 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 fall within the above ranges, is used as the polymer, the obtained 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 in a flow tester under conditions of a nozzle 1 mm × 10 mm, a load 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 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, there is a possibility that low energy fixing cannot be performed. The lower limit of the glass transition temperature [Tg] of the polymer is usually 40 ° C. or higher, preferably 50 ° C. or higher. If the glass transition temperature [Tg] of the polymer is too low, the blocking resistance may be lowered. Here, the glass transition temperature [Tg] of the polymer is the intersection of the two tangent lines by drawing a tangent line at the start of the transition (inflection) of the curve measured at a heating rate of 10 ° C./min in a differential scanning calorimeter. It can be calculated as the temperature.

The softening point and glass transition temperature [Tg] of the polymer can be adjusted to the above ranges by adjusting the kind of the polymer, the monomer composition ratio, the molecular weight, and the like.
<Mixing process and aggregation process>
The emulsion in which the polymer primary particles are dispersed is mixed and aggregated to obtain an emulsion of aggregates (aggregated particles) containing the polymer and the pigment. 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. At this time, the polymer primary particles may be used alone or in combination of two or more in any combination and ratio. Furthermore, polymer primary particles (hereinafter referred to as “combined polymer particles” as appropriate) produced with 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. Examples of this resin include vinyl acetate, vinyl chloride, vinyl, in addition to the above-mentioned monomer (co) polymer used for emulsion polymerization. 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 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 combined 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 combined 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 too large , the sedimentation property in a liquid medium tends to deteriorate. In addition, considering issues 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 the carbon black particles is correlated with the amount of impurities contained in the carbon black (the degree of residual undecomposed organic matter). 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, the carbon black of the channel method tends to have a large amount of impurities, so that the carbon black used in the toner 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 placed 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.

As yellow pigments, for example, compounds typified by condensed azo compounds and isoindolinone compounds are used. 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 preferably used.
Further, examples of magenta pigments 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 or the like is preferably used.

  Among them, C.I. I. Pigment red 122, 202, 207, 209, C.I. I. A quinacridone pigment represented by pigment violet 19 is particularly 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 that can be used 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 can be used particularly preferably.
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, so the probability that the pigment particles are re-aggregated during the dispersion is increased. When the blending amount is less than the above range, the dispersion is excessive and an appropriate particle size distribution is obtained. 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 preferably used. 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 is used. At this time, the water quality of the polymer primary particles and the pigment particle dispersion is also related to the coarsening due to reaggregation of each particle, and when the conductivity is high, the dispersion stability with time tends to 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 (a personal SC meter model SC72 and a detector SC72SN-11 manufactured by Yokogawa Electric Corporation).

Moreover, when mixing a pigment with the emulsion containing a polymer primary particle, you may mix a wax with an 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 metal salts or metal complexes of acids, amide compounds, phenol compounds, naphthol compounds, and phenol amide compounds. Among these, colorless or light-colored ones are preferably selected in order to avoid color tone problems as toners, and quaternary ammonium salts and imidazole compounds are particularly preferable as positively chargeable charge control agents, and negatively chargeable charge control agents. As these, alkyl salicylic acid complex compounds and curixarene compounds containing atoms such as Cr, 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, Usually, 0.01 mass part or more 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, the charge control agent is desirably mixed at the time of agglomeration in a state emulsified in a liquid medium (usually an aqueous medium) as in the case of the pigment particles.
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. Among these, a method of mixing an electrolyte is preferable.
Examples of the electrolyte when the aggregation is performed by mixing the electrolyte include chlorides such as NaCl, KCl, LiCl, MgCl ₂ , and CaCl ₂ ; Na ₂ SO ₄ , K ₂ SO ₄ , Li ₂ SO ₄ , MgSO ₄ , Examples include inorganic salts such as sulfates such as CaSO ₄ , ZnSO ₄ , Al ₂ (SO ₄ ) ₃ , and 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 the electrolyte used varies depending on the type of the 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 with respect to 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 progress of the agglutination reaction slows down and fine particles of 1 μm or less remain after the agglomeration reaction, or the average particle size of the obtained agglomerates is the target. There is a possibility that the particle size will not be reached, and 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 a polymer primary particle polymer glass transition temperature [Tg] or lower, preferably 55 ° C. or lower. . Although the time for agglomeration is also arbitrary, it is usually 10 minutes or longer, preferably 60 minutes or longer, and usually 300 minutes or shorter, preferably 180 minutes or shorter.

Moreover, it is preferable to stir when aggregating. 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. This is preferable because it does not cause deterioration (such as thermal deterioration).

<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 a 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, By spraying and drying, a resin coating layer can be formed on the surface of the aggregate.

  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, an apparatus such as a hybridization system (manufactured by Nara Machinery Co., Ltd.) or a mechanofusion system (manufactured by Hosokawa Micron Corporation) can be used.

Further, as the in-situ polymerization method, for example, the aggregate is dispersed in water, the monomer and the 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 may be, for example, a method in which an aggregate forming an inner layer and resin fine particles forming an outer layer are reacted or bonded in an aqueous medium to form a resin coating layer on the surface of the aggregate forming the inner layer. It is the 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 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 based on the toner particles. Is desirable.
Furthermore, in order to effectively fix or fuse the resin fine particles to the aggregate, the resin fine particles usually have a particle size of about 0.04 to 1 μm.

  The glass transition temperature [Tg] of the polymer component (resin component) used in the resin coating layer is usually 60 ° C. or higher, preferably 70 ° C. or higher, and usually 110 ° C. or lower. Further, the glass transition temperature [Tg] of the polymer component used in 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. It is more preferable. If the glass transition temperature [Tg] is too low, storage in a general environment is difficult, and if it is too high, sufficient meltability cannot 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% by mass or less in the toner. Preferably it is 1 mass% or less, More preferably, you may be 0.5 mass% or less. 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 be lowered.

  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 fusion process, 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 time for the heat treatment is usually 0.5 to 6 hours although it depends on the treatment capacity and the production amount.
<Washing and drying process>
When each of the above steps is performed in a liquid medium, the toner can be obtained by washing the encapsulated resin particles obtained after the fusing step and drying to remove the liquid medium. There are no restrictions on the washing and drying methods, and they are arbitrary.

<Physical properties relating to toner particle size>
There is no limitation on the volume average particle diameter [Dv] of the toner, and it is optional as long as the effects of the present invention are not significantly impaired. 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.

  The toner has a value [Dv / Dn] obtained by dividing the volume average particle diameter [Dv] by the number average particle diameter [Dn], usually 1.0 or more, and usually 1.25 or less, preferably 1.20. Below, it is desirable that it is 1.15 or less more preferably. 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.

  Further, the toner has a volume fraction of a particle size of 25 μm or more, usually 1% or less, preferably 0.5% or less, more preferably 0.1% or less, and still more preferably 0.05% 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 stable. Although it is most preferable that there is no coarse powder having a particle size of 25 μm or more, it is difficult in actual production, and usually it may not be 0.005% or less.

The toner has a volume fraction of 15 μm or more in particle size, usually 2% or less, preferably 1% or less, more preferably 0.1% or less. Although it is most preferable that there is no coarse powder having a particle size of 15 μm or more, it is difficult in actual production, and usually it may not be 0.01% or less.
Further, it is desirable that the toner has a number fraction having a particle size of 5 μm or less, which is usually 15% or less, preferably 10% or less, in order to improve image fog.

  Here, the volume average particle diameter [Dv], the number average particle diameter [Dn], the volume fraction, the number fraction, and the like of the toner can be measured as follows. That is, as a toner particle size measuring device, a multisizer type II or type III (manufactured by Beckman Coulter, Inc.) of a Coulter counter is used, and an interface for outputting the number distribution / 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 a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and measured using a multisizer type II or type III of the Coulter counter using a 100 μm aperture. 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 molecular weight of the toner>
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 is usually 10,000 or more, preferably 20,000 or more, more preferably 30,000 or more. Yes, usually 150,000 or less, preferably 100,000 or less,
More preferably, it is 70,000 or less. THF refers to 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 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 whose sample concentration (resin concentration) is adjusted to 0.05 to 0.6 mass%. In measuring the molecular weight of the sample (resin component in the toner), the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical Co. Manufactured by Toyo Soda Kogyo Co., Ltd., with molecular weights of 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , It is appropriate to use 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ , and use at least about 10 standard polystyrene samples. 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-styragel 500, 103, 104, 105 and a combination of shodex KA801, 802, 803, 804, 805, 806, 807 manufactured by Showa Denko KK are preferable.

Further, the measurement of the insoluble content of tetrahydrofuran (THF) in the toner can be 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, and then filtered using 10 g of Celite. Insoluble matter can be calculated.
<Softening point and glass transition temperature of toner>
There is no limitation on the softening point [Sp] of the toner, and it is optional as long as the effects of the present invention are not significantly impaired. 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 toner softening point [Sp] was 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 can be obtained.
Further, there is no limitation on the glass transition temperature [Tg] of the toner, and it is arbitrary as long as the effects of the present invention are not significantly impaired. . 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 rising rate of 10 ° C./min. It can be determined as temperature.
The softening point [Sp] and glass transition temperature [Tg] of the toner are greatly influenced by the type and composition ratio of the polymer contained in the toner. Therefore, the softening point [Sp] and the 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 type of low melting point components such as wax, and the blending amount.

<Wax in toner>
When the toner contains 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 the average particle diameter, and the upper limit is usually 3 μm or less, preferably 1 μm. It is as follows. 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 be reduced. May be reduced.

The dispersed particle diameter of the wax is not limited to the method in which the toner is thinned and observed under an electron microscope, or the toner polymer is eluted with an organic solvent or the like in which the wax does not dissolve, and then filtered through a filter. Can be confirmed by a method of measuring with a microscope.
Further, the proportion of the wax in the toner is arbitrary as long as the effects of the present invention are not significantly impaired, but is usually 0.05% by mass or more, preferably 0.1% by mass or more, more preferably 1% by mass or more, More preferably, it is 4% by mass or more, usually 20% by mass or less, preferably 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 temperatures, and the like, external additive fine particles may be added 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 type 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. In particular, it is preferable to use a high-speed agitation type mixer such as a Henschel mixer or a super mixer, 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, and the like.

In addition, as a device used for fixing toner particles and externally added fine particles by 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.
The 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 relative to each other while maintaining a gap. By being forced to pass through the portion, compressive stress and shear stress are applied to the particle surface without being substantially pulverized. 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 instantaneously heating the mixture of the basic fine particles and the externally added fine particles above the melting start temperature of the basic fine particles using a hot air stream or the like. 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.

  Examples of the inorganic fine particles include silicon carbide, boron carbide, titanium carbide, zirconium carbide, hafnium carbide, vanadium carbide, tantalum carbide, niobium carbide, tungsten carbide, chromium carbide, molybdenum carbide, calcium carbide and the like, boron nitride, nitriding Nitride such as titanium, zirconium nitride, silicon nitride, boride such as zirconium boride, silica, colloidal silica, titanium oxide, aluminum oxide, calcium oxide, magnesium oxide, zinc oxide, copper oxide, zirconium oxide, cerium oxide, talc , Oxides and hydroxides such as hydrotalcite, various titanate compounds such as calcium titanate, magnesium titanate, strontium titanate, barium titanate, tricalcium phosphate, calcium dihydrogen phosphate, monohydrogen phosphate calcium Phosphoric compounds such as substituted calcium phosphates in which a portion of the phosphate ions is replaced by anions, sulfides such as molybdenum disulfide, fluorides such as magnesium fluoride and fluorocarbon, aluminum stearate, calcium stearate, stearic acid Various carbon blacks including metal soaps such as zinc and magnesium stearate, talc, bentonite, and conductive carbon black can be used. Furthermore, magnetic substances 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 can be used.
Among these externally added fine particles, silica, titanium oxide, alumina, zinc oxide, carbon black and the like are particularly preferably used.

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 treatment agent such as a coupling agent having a secondary 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 can be determined by observation with an electron microscope, conversion from the value of the 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%. Desirably, it is not more than mass%, preferably not more than 6 mass%, more preferably not more than 4 mass%. If the amount of the externally added fine particles is too small, the fluidity and the charging stability may be insufficient, and if the amount is too large, the fixability may be deteriorated.

<Toner and others>
The charging characteristics of the toner 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 toner base particle components such as a charge control agent, the selection and composition ratio of externally added fine particles, and the like.

Further, the toner 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, ferrite, or magnetite carrier, or a resin on the surface thereof. A coated one or a magnetic resin carrier 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, but are not limited thereto. Is not to be done.
The average particle size of the carrier is not particularly limited, but those having an average particle size 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.

The formation of a full-color image by electrophotography can be carried out by a conventional method using magenta, cyan, and yellow color toners and, if necessary, black toner.
<Cartridge, image forming apparatus>
Next, a drum cartridge and an image forming apparatus using the electrophotographic photosensitive member of the present invention will be described with reference to FIG.

  In FIG. 1, reference numeral 1 denotes a drum-shaped photoconductor, which is driven to rotate about a shaft 2 in the direction of an arrow at a predetermined peripheral speed. The photosensitive member 1 is uniformly charged with a predetermined positive or negative potential on the surface by the charging unit 3 during the rotation process, and then exposure for forming a latent image is performed by the image exposure unit in the exposure unit 4. The formed electrostatic latent image is then developed with toner by the developing means 5, and the toner developed image is sequentially transferred to a transfer body (paper or the like) 7 fed from the paper feeding unit by the corona transfer means 6. . The image-transferred transfer body is then sent to the fixing unit 8 where the image is fixed and printed out of the apparatus. The surface of the photoconductor 1 after the image transfer is cleaned by the cleaning unit 9 to remove the transfer residual toner, and is neutralized by the neutralizing unit 10 for the next image formation.

  In using the electrophotographic photoreceptor of the present invention, as a charger, in addition to a corona charger such as corotron and scorotron shown in FIG. 1, a directly charged member to which voltage is applied is brought into contact with the surface of the photoreceptor. Direct charging means for charging may be used. Examples of the direct charging means include a contact charger such as a charging roller and a charging brush. As the direct charging means, any one that involves air discharge or injection charging that does not involve air discharge is possible. In addition, as a voltage applied at the time of charging, in the case of only a direct current voltage, an alternating current can be superimposed on a direct current.

For the exposure, a halogen lamp, a fluorescent lamp, a laser (semiconductor, He—Ne), LED, a photoreceptor internal exposure system, or the like is used. As a digital electrophotographic system, it is preferable to use a laser, an LED, an optical shutter array, or the like. . As the wavelength, in addition to 780 nm monochromatic light, it is possible to use monochromatic light in the 600 to 700 nm region and slightly shorter wavelength.
In the development process, a dry development method such as cascade development, one-component insulating toner development, one-component conductive toner development, two-component magnetic brush development, or the like is used. As the toner, in addition to the pulverized toner, chemical toners such as suspension granulation, suspension polymerization, and emulsion polymerization aggregation can be used. In particular, in the case of chemical toners, those having a small particle diameter of about 4 to 8 μm are used, and those having a shape close to a sphere, and those outside the potato-like sphere can also be used. The polymerized toner is excellent in charging uniformity and transferability, and is preferably used for high image quality.

For the transfer process, electrostatic transfer methods such as corona transfer, roller transfer and belt transfer, pressure transfer method, and adhesive transfer method are used. For fixing, heat roller fixing, flash fixing, oven fixing, pressure fixing, IH fixing, belt fixing, IHF fixing, etc. are used. These fixing methods may be used alone or in combination with a plurality of fixing methods. May be.
Brush cleaning, magnetic brush cleaner, electrostatic brush cleaner, magnetic roller cleaner, blade cleaner, etc. are used for cleaning.

In many cases, the static elimination step is omitted, but when used, a fluorescent lamp, LED, or the like is used, and an exposure energy that is three times or more of the exposure light is often used as the intensity.
In addition to these processes, a pre-exposure process and an auxiliary charging process may be included.
In the present invention, a plurality of components such as the drum-shaped photosensitive member 1, the charging unit 3, the developing unit 5, and the cleaning unit 9 are integrally coupled as a drum cartridge, and the drum cartridge is copied. It may be configured to be detachable from the main body of an electrophotographic apparatus such as a machine or a laser beam printer. For example, at least one of the charging unit 3, the developing unit 5, and the cleaning unit 9 can be integrally supported together with the drum-shaped photoconductor 1 to form a cartridge.

Hereinafter, the present invention will be described in more detail with reference to production examples, examples and comparative examples. In addition, the following examples are shown in order to describe the present invention in detail, and the present invention is not limited to the following examples unless it is contrary to the gist thereof.
<Method for making photoconductor>
10 parts by weight of a phthalocyanine compound was added to 150 parts by weight of 4-methoxy-4-methylpentanone-2, and pulverized and dispersed in a sand grind mill for 1 hour. Further, 5 parts by weight of polyvinyl butyral (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name: Denka Butyral # 6000C) 5 wt% 1,2-dimethoxyethane solution and 5 parts by weight of phenoxy resin (Union Carbide, trade name PKHH) 1, A binder solution was prepared by mixing 100 parts of a 2-dimethoxyethane solution. 100 parts by weight of the binder solution and 1,2-dimethoxyethane were added to 160 parts by weight of the previously prepared pigment dispersion to finally prepare a coating solution for a charge generation layer having a solid content concentration of 4.0%.

The dispersion thus obtained was applied onto a 75 μm thick polyethylene terephthalate film having aluminum deposited on the surface so that the film thickness after drying was 0.3 μm to provide a charge generation layer.
Next, on this film, 50 parts by weight of a charge transport material, 100 parts by weight of a polycarbonate resin having the following structural formula (m: n = 51: 49, viscosity average molecular weight 30,000), and 0.05 weight of silicone oil as a leveling agent A charge transport layer coating solution was prepared by dissolving 640 parts by weight in 640 parts by weight of a tetrahydrofuran / toluene mixed solvent (mixing ratio 80:20). The prepared charge transport layer coating solution is applied onto the charge generation layer provided earlier, dried at 125 ° C. for 20 minutes, and provided with a charge transport layer so that the film thickness after drying is 25 μm. Obtained.

An electrophotographic photoreceptor was prepared according to the above <Photoreceptor preparation method>. The combinations of phthalocyanine compounds and charge transport materials used in each electrophotographic photosensitive member are shown in Table 1 below.
<Evaluation of electrical characteristics of photoconductor>
Using an electrophotographic characteristic evaluation apparatus (basic and applied electrophotographic technology, edited by the Electrophotographic Society, Corona, pages 404-405) prepared according to the Electrophotographic Society measurement standard, the photoconductor is made into an aluminum drum. Attached to a cylindrical shape, the aluminum drum and the aluminum base of the photoconductor are connected, and then the drum is rotated at a constant rotational speed, and an electrical property evaluation test is performed by a cycle of charging, exposure, potential measurement, and static elimination. went. At that time, the initial surface potential was −700 V, exposure was 780 nm, and charge removal was monochromatic light of 660 nm. As the surface potential (VL) when 780 nm light was irradiated at 1.0 μJ / cm ² and the index representing sensitivity, the exposure amount (half exposure amount) required to halve the surface potential to −350 V was measured. In the VL measurement, the time required for the exposure-potential measurement was 100 ms. The measurement environment was a temperature of 25 ° C. and a relative humidity of 50%. It shows that an electrical property is so favorable that the absolute value of a sensitivity (half exposure amount) and the value of VL is small. The results of electrical characteristics are shown in Table 1 below.

  From the above results, when a metal-containing phthalocyanine is used as a charge generation material and a tertiary naphthylamine compound having a specific structure is used as a charge transport material, a photoconductor having high sensitivity and low residual potential characteristics can be obtained. Recognize. On the other hand, in Comparative Examples 3 to 5, a metal-containing phthalocyanine and a metal-free phthalocyanine are used as charge generation materials in the case of using a wholly aromatic-substituted tertiary amine that is not a tertiary naphthylamine compound having a specific structure. It can be seen that there is not much difference in VL compared to the case where it was.

Example 5:
The charge generating layer coating solution used in Example 1 was dip-coated on an aluminum cylinder having a diameter of 30 mm, a length of 250 mm, and a wall thickness of 0.75 mm, which had been anodized and sealed, and dried. The charge generation layer was provided so that the film thickness of the film was 0.4 g / m ² (about 0.4 μm). Then, the charge transport layer coating solution obtained in Example 1 is dip-coated on the charge generation layer, and the charge transport layer is provided so that the film thickness after drying is 18 μm. A photographic photoreceptor (photoreceptor drum A1) was produced.

Example 6:
Photosensitive drum A2 was produced by performing the same operation as in Example 1 except that the charge generation layer coating solution and the charge transport layer coating solution were changed to those used in Example 2.
Example 7:
Photosensitive drum A3 was produced by performing the same operation as in Example 1, except that the charge generation layer coating solution and the charge transport layer coating solution were changed to those used in Example 3.

Example 8:
Photosensitive drum A4 was produced by performing the same operation as in Example 1 except that the charge generation layer coating solution and the charge transport layer coating solution were changed to those used in Example 4.
Comparative Example 6:
A comparative photosensitive drum AE1 was produced by performing the same operation as in Example 1 except that the charge generation layer coating solution and the charge transport layer coating solution were changed to those used in Comparative Example 1.

Comparative Example 7:
A comparative photosensitive drum AE2 was produced by performing the same operation as in Example 1 except that the charge generation layer coating solution and the charge transport layer coating solution were changed to those used in Comparative Example 2.
The photosensitive drums obtained in Examples 5 to 8 and Comparative Examples 6 and 7 were mounted on a drum cartridge of a commercially available monochrome laser printer (LP2400 manufactured by Seiko Epson Corporation), and the temperature was 35 ° C. and the relative humidity was 80%. Printing was performed and image evaluation was performed. Table 2 shows the fog value.

  The fog value is adjusted using a colorimetric color difference meter (Nippon Denshoku Industries Co., Ltd. ND-1001DP type) so that the whiteness of the standard white board is 94.4, and printed using this colorimetric color difference meter. The whiteness of the previous paper (A4 size) is measured, and printing is performed on the same paper by inputting a signal that turns the entire surface white into the laser printer. The whiteness was measured and obtained by calculation based on the following formula (1).

            Fog value = Whiteness before printing-Whiteness after printing (1)

From the results in Table 2, it can be seen that the electrophotographic photosensitive member of the present invention has a low fog value and a good image as compared with the electrophotographic photosensitive members of Comparative Examples 6 and 7.
Example 9:
The surface of an aluminum cylinder having a mirror-finished outer diameter of 30 mm, length of 376 mm, and wall thickness of 0.75 mm is anodized and then sealed with a sealant mainly composed of nickel acetate. By performing, an anodic oxide film (alumite film) of about 6 μm was formed. The charge generation layer coating solution and charge used in Example 1 except that the undercoat layer forming coating solution shown below was applied onto the cylinder on which the alumite film was formed to form a 1.5 μm undercoat layer. The transport layer coating solution is sequentially applied onto the undercoat layer by dip coating, and a charge generation layer and a charge transport layer are formed so that the film thickness after drying is 0.4 μm and 18 μm, respectively. I got a drum.

<Method for adjusting coating liquid for forming undercoat layer>
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 Compound represented by (B)] / Hexamethylenediamine [Compound represented by the following formula (C)] / Decamethylene dicarboxylic acid [Compound represented by the following formula (D)] / Octadecamethylene dicarboxylic acid [Formula ( The compound represented by E)] was stirred and mixed with pellets of copolymerized polyamide having a composition molar ratio of 60% / 15% / 5% / 15% / 5% to dissolve the polyamide pellets. After that, ultrasonic dispersion treatment with an ultrasonic transmitter with an output of 1200 W is performed for 1 hour, and a PTFE membrane filter (adva The weight ratio of the surface-treated titanium oxide / copolymerized polyamide is 3/1 and the weight ratio of the mixed solvent of methanol / 1-propanol / toluene is 7/1/2. Thus, a coating solution for forming an undercoat layer having a solid content concentration of 18.0% by weight was obtained.

The manufactured photoconductor drum is printed on a color printer MICROLINE Pro manufactured by Oki Data.
It was mounted on a 9800PS-E black drum cartridge. Next, a developing toner (volume average particle size 7.05 μm, Dv / Dn = 1.14, average circularity 0. 10 μm) manufactured according to the manufacturing method (emulsion polymerization aggregation method) of developing toner A disclosed in Japanese Patent Application Laid-Open No. 2007-213050. 963) was mounted on a black toner cartridge. These drum cartridges and toner cartridges were mounted on the printer.

Specifications of MICROLINE Pro 9800PS-E 4 tandem color 36ppm, monochrome 40ppm
1200 dpi
Contact roller charging (DC voltage applied)
LED exposure With static elimination light Initial and 1,000-sheet image formation in an environment with a temperature of 35 ° C and a humidity of 80% gives a good image with no image degradation such as ghosting, fogging, and density reduction. It was.

Example 10:
Results of creating and evaluating an electrophotographic photosensitive member by performing the same operations as in Example 9 except that the charge generation layer coating solution and the charge transport layer coating solution were changed to those used in Example 3. Similarly, a good image without image deterioration such as ghost, fogging and density reduction was obtained.

Claims (6)

An electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the photosensitive layer contains a tertiary naphthylamine compound represented by the following general formula (1) and a metal phthalocyanine: body.

(In the general formula (1), Ar ₁ and Ar ₂ represent an aryl group having 10 or less carbon atoms constituting the aromatic ring, R represents a substituent other than hydrogen, and n represents an integer of 0 to 7. The aryl group may have a substituent.) _2. The electrophotographic photosensitive member according to claim ₁ , wherein Ar ₁ and Ar ₂ are phenyl groups which may have a substituent. 2. The electrophotographic photosensitive member according to claim 1, wherein the metal phthalocyanine is titanyl phthalocyanine. 4. The electrophotographic photosensitive member according to claim 3, wherein titanyl phthalocyanine has a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° in a powder X-ray diffraction spectrum by CuKα characteristic X-ray. . 5. The electrophotographic photosensitive member according to claim 1, 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. An electrophotographic photosensitive member cartridge comprising: a developing unit that develops an electrostatic latent image formed thereon; and a cleaning unit that cleans the electrophotographic photosensitive member. The electrophotographic photosensitive member according to claim 1, 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 An image forming apparatus comprising: a developing unit that develops an electrostatic latent image formed on a body.

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