JPH10104860A - Electrophotographic photoreceptor, process cartridge with the same and electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure superior electrophotographic characteristics and superior durability after repetition and to prevent the occurrence of a transfer memory by forming a photosensitive layer contg. a specified fluorene compd. and a hindered phenol compd. SOLUTION: This electrophotographic photoreceptor has a photosensitive layer contg. a fluorene compd. represented by the formula and a hindered phenol compd. on the substrate. In the formula, each of R1 -R4 is optionally substd. aryl, each of R5 and R6 is H, optionally substd. alkyl, optionally substd. aryl or optionally substd. aralkyl, the aryl is, e.g. phenyl or naphthyl, the alkyl is, e.g. methyl or ethyl and the aralkyl is, e.g. benzyl or phenetyl.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member, and more particularly, to an electrophotographic photosensitive member having improved electrophotographic characteristics. Further, the present invention relates to a process cartridge having the electrophotographic photosensitive member and an electrophotographic apparatus.

[0002]

2. Description of the Related Art Conventionally, inorganic photoconductive materials such as selenium, zinc oxide and cadmium sulfide have been widely used for electrophotographic photosensitive members.

In recent years, it is highly safe and suitable for mass production.
Due to advantages such as low cost, research on using an organic photoconductive material for an electrophotographic photosensitive member has been actively conducted, and many photosensitive members have been proposed and put into practical use. Among them, a stacked photoreceptor having a charge generating layer containing a charge generating material and a charge transporting layer containing a charge transporting material has become the mainstream of research because of its excellent electrophotographic characteristics such as sensitivity. .

[0004] However, in the above-mentioned laminated photoreceptor,
By repeating image forming processes such as charging, exposure, development, transfer, and static elimination, a reduction in charging potential and a change in bright portion potential occur, causing defects such as fogging and blurring in the image, and although the durability is sufficient. There were many things that did not exist.

[0005] These causes are considered to be deterioration due to O ₃ , NOx, SOx and the like generated during charging, deterioration due to light irradiation, and the like. It is known to add a specific antioxidant to the photosensitive layer in order to prevent such deterioration of the material, particularly deterioration due to oxidation.
-265666, JP-A-63-50848, JP-A-63-52150, JP-A-64-44
451, JP-A-3-170941, JP-A-4-51248, JP-A-5-297613, and the like.

[0006]

However, these photoreceptors do not have a sufficient antioxidant effect, and the addition of an antioxidant deteriorates electrophotographic characteristics such as sensitivity and residual potential. there were.

Further, in a reversal developing system corresponding to recent digitization, since a primary charge and a transfer charge have opposite polarities, a so-called transfer memory having a different chargeability depending on the presence or absence of a transfer occurs, resulting in very uneven density on an image. It is easy to appear.

An object of the present invention is to provide an electrophotographic photosensitive member having both excellent electrophotographic characteristics and excellent repetition durability.

It is another object of the present invention to provide an electrophotographic photosensitive member in which transfer memory is less likely to occur.

[0010]

That is, the present invention relates to an electrophotographic photosensitive member having a photosensitive layer on a support, wherein the photosensitive layer has the following formula (1):

[0011]

[Outside 4] (Wherein, R ₁ , R ₂ , R ₃ and R ₄ are the same or different and each represents a substituted or unsubstituted aryl group, and R ₅ and R ₆ are the same or different and represent a hydrogen atom, a substituted or unsubstituted An alkyl group, a substituted or unsubstituted aryl group and a substituted or unsubstituted aralkyl group). And a hindered phenol compound.

Further, the present invention is a process cartridge and an electrophotographic apparatus having the above electrophotographic photosensitive member.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the formula (1), examples of the aryl group include a phenyl group, a naphthyl group and a pyrenyl group.
Examples of the alkyl group include a methyl group, an ethyl group, a propyl group and a butyl group, and examples of the aralkyl group include a benzyl group, a phenethyl group and a naphthylmethyl group.

The substituents which these groups may have include alkyl groups such as methyl group, ethyl group and propyl group, alkoxy groups such as methoxy group and ethoxy group, and aryl groups such as phenyl group and naphthyl group. And the like.

Preferably, R ₅ and R ₆ are not both hydrogen atoms at the same time.

The hindered phenol compound used in the present invention is a phenol compound having a structure (hindered phenol structure) having a substituent at at least one of an ortho position of a hydroxyl group and an alkoxy group directly bonded to a benzene ring. It is. Although various substituents may be mentioned, an alkyl group and an aralkyl group are preferred.

Examples of the alkyl group include linear or branched propyl, butyl, pentyl, hexyl and octyl groups, and cyclic cyclopentyl and cyclohexyl. Examples of the aralkyl group include a benzyl group and a phenethyl group.

These groups may have a substituent. Examples of the substituent include an alkyl group such as a methyl group and an ethyl group, an alkoxy group such as a methoxy group and an ethoxy group, and fluorine, chlorine and bromine. And the like.

Preferred examples of the fluorene compound and the hindered phenol compound represented by the formula (1) are shown below, but the present invention is not limited thereto. Examples of the fluorene compound are CT-No. In HP-No. Indicated by

[0020]

[Outside 5]

[0021]

[Outside 6]

[0022]

[Outside 7]

[0023]

[Outside 8]

[0024]

[Outside 9]

[0025]

[Outside 10]

[0026]

[Outside 11]

[0027]

[Outside 12]

[0028]

[Outside 13]

[0029]

[Outside 14]

[0030]

[Outside 15]

[0031]

[Outside 16]

[0032]

[Outside 17] Among these, CT-4, CT-10, CT-12,
CT-19, CT-20 and CT-21 are preferred.

[0033]

[Outside 18]

[0034]

[Outside 19]

[0035]

[Outside 20]

[0036]

[Outside 21]

[0037]

[Outside 22]

[0038]

[Outside 23]

[0039]

[Outside 24]

[0040]

[Outside 25]

[0041]

[Outside 26] Among these, HP-1 and HP-12 are preferred.

The fluorene compound used in the present invention is
It can be synthesized by the method described in JP-A-62-208054. Further, the hindered phenol compound used in the present invention can be synthesized by various methods, and some of the exemplified compounds can be obtained as commercial products.

The electrophotographic photoreceptor of the present invention may take any form as long as it is a photosensitive layer containing a fluorene compound and a hindered phenol compound in the same layer. For example,
Even a single layer type in which the charge generation material and the charge transport material are contained in the same layer, a stacked type in which the charge generation layer containing the charge generation material and the charge transport layer containing the charge transport material are functionally separated. You may. In the present invention, it is preferable that the charge transport layer is a stacked type, and it is particularly preferable that the charge transport layer is formed on the charge generation layer.

First, the laminated photoreceptor will be described.

The charge transport layer in the present invention can be formed by applying a solution obtained by dissolving a fluorene compound and a hindered phenol compound, which are charge transport materials, and a binder resin in an appropriate solvent, and drying the solution. The mixing ratio of the fluorene compound and the hindered phenol compound is preferably 0.03 to 30 parts by weight, more preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the fluorene compound. Is preferred.

As the binder resin to be used, conventionally used resins for the charge transport layer can be used. For example, polyarylate, polysulfone, polyamide, acryl,
Examples include resins such as acrylonitrile, methacryl, vinyl chloride, vinyl acetate, phenol, epoxy, polyester, polycarbonate, and polyurethane. The mixing ratio of the binder resin and the charge transport material of the present invention is such that the charge transport material is 10 to 500 parts by weight per 100 parts by weight of the binder resin.
It is preferable to use parts by weight. The thickness of the charge transport layer is 5
４０40 μm, especially 10-30 μm
m is preferable.

The charge generation layer in the present invention can be formed by applying a dispersion in which the charge generation material is dispersed in a binder resin, and drying. As a charge generation material,
For example, quinone pigments, perylene pigments, indigo pigments, azurenium pigments, azo pigments, phthalocyanine pigments and the like can be mentioned. Among these charge generation materials, azo pigments and phthalocyanine pigments are particularly suitable in the present invention.

Examples of the phthalocyanine pigment include metal-free phthalocyanine, copper phthalocyanine, gallium phthalocyanine, and oxytitanium phthalocyanine. The fluorene compound used in the present invention has a relatively low oxidation potential. Titanium phthalocyanine is preferred. Oxytitanium phthalocyanine is disclosed in, for example, JP-A-61-239248.
JP, JP-A-62-67094, JP-A-3-1
No. 28973 and JP-A-3-200790. Among them, Japanese Patent Application Laid-Open No. Hei 3-128973
Nos. 9.0, 14.2, and 23.23 of the Bragg angles (2θ ± 0.2 °) in the characteristic X-ray diffraction of CuKα described in Japanese Patent Application Laid-Open No. H10-260, 1988.
Oxytitanium phthalocyanine, which is a crystalline form having characteristic peaks at 9 ° and 27.1 °, is more preferred.

The binder resin used can be selected from a wide range of insulating resins, such as polyvinyl butyral, polyvinyl alcohol, polyarylate, polyamide, acrylic resin, polyvinyl acetate, phenol resin, epoxy resin, polyester, polycarbonate, polyurethane and Resins such as cellulose are exemplified. The content of the resin in the charge generation layer is preferably 80% by weight or less,
In particular, it is preferably at most 50% by weight. The thickness of the charge generation layer is preferably 5 μm or less, particularly preferably 0.05 to 2 μm.

Next, the single-layer type photosensitive layer will be described.

The single-layer type photosensitive layer is formed by applying and drying a solution obtained by dissolving and dispersing a fluorene compound and a hindered phenol compound, which are charge transporting materials, and a charge generating material in the above resin with an appropriate solvent. Can be.
The thickness of the single-layer type photosensitive layer is preferably from 5 to 40 μm, and particularly preferably from 10 to 30 μm.

The support to be used in the present invention may be any support as long as it has conductivity. For example, metals and alloys such as aluminum, chromium, nickel, stainless steel, copper and zinc; A metal foil laminated on a plastic film; aluminum, indium oxide, tin oxide, etc. deposited on a plastic film; or a metal provided with a conductive layer by applying a conductive substance alone or with an appropriate binder resin; Examples include plastic films and paper.

Examples of the conductive substance include metal powders such as aluminum, copper, nickel and silver; metal foils and metal fibers; conductive metal oxides such as antimony oxide, indium oxide and tin oxide; polypyrrole, polyaniline and Polymer conductive materials such as molecular electrolytes; carbon black, graphite powder and organic or inorganic electrolytes; and conductive powders whose surfaces are coated with these conductive materials.

Examples of the shape of the support include a drum shape, a sheet shape, a belt shape and the like, and a shape most suitable for the applied electrophotographic apparatus is preferable.

In the present invention, an undercoat layer may be provided between the support and the photosensitive layer. The undercoat layer functions as a barrier layer or an adhesive layer for controlling charge injection at the interface with the photosensitive layer. The undercoat layer is mainly made of a resin, but may contain the above-mentioned metal or alloy, or an oxide, salt, surfactant or the like thereof. Examples of the resin forming the undercoat layer include polyester, polyurethane, polyacrylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, phenol resin, acrylic resin, silicone resin, epoxy resin, urea resin, allyl resin, and alkyd. Resins, polyamide imide, polysulfone, polyallyl ether, polyacetal, butyral resin, and the like. The thickness of the undercoat layer is preferably from 0.05 μm to 7 μm, particularly preferably from 0.1 to 2 μm.

The various layers described above can be formed by vapor deposition or coating. In particular, a coating method is preferable because films having various compositions can be formed in a wide range from a thin film to a thick film. Application methods include dip coating, spray coating, beam coating,
Examples include a bar coating method, a blade coating method, and a roller coating method.

The electrophotographic photosensitive member of the present invention can be used not only for an electrophotographic copying machine but also for a laser beam printer,
It can be widely used in electrophotographic applications such as CRT printers, LED printers, liquid crystal printers, facsimile machines, and laser plate making machines.

FIG. 1 shows a schematic configuration of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention.

In FIG. 1, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is driven to rotate around an axis 2 in a direction of an arrow at a predetermined peripheral speed. The photoreceptor 1 rotates during the rotation process.
The peripheral surface thereof is uniformly charged with a predetermined positive or negative potential by the primary charging unit 3 and then receives image exposure light 4 from an image exposure unit (not shown) such as slit exposure or laser beam scanning exposure. Thus, an electrostatic latent image is sequentially formed on the peripheral surface of the photoconductor 1. The formed electrostatic latent image is then subjected to toner development by the developing unit 5, and the developed toner developed image is transferred between the photoconductor 1 and the transfer unit 6 from a paper feeding unit (not shown) by rotation of the photoconductor 1. Transfer material 7 synchronized and fed
Are sequentially transferred by the transfer means 6.

The transfer material 7 having undergone the image transfer is separated from the surface of the photoreceptor, introduced into the image fixing means 8 and subjected to image fixing, thereby being printed out of the apparatus as a copy.

After the transfer of the image, the surface of the photoreceptor 1 is cleaned by the cleaning unit 9 to remove the untransferred toner, and the pre-exposure light 10 from the pre-exposure unit (not shown).
Is used for image formation repeatedly after the charge removal processing. When the primary charging unit 3 is a contact charging unit using a charging roller or the like, the pre-exposure is not necessarily required.

In the present invention, a plurality of components such as the above-described electrophotographic photosensitive member 1, primary charging means 3, developing means 5, and cleaning means 9 are integrally connected as a process cartridge. This process cartridge may be configured to be detachable from a main body of an electrophotographic apparatus such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 3, the developing unit 5, and the cleaning unit 9 is integrally supported together with the photoreceptor 1 to form a cartridge, which can be attached to and detached from the apparatus main body using a guide unit such as a rail 12 of the apparatus main body. Process cartridge 1
It can be 1.

When the electrophotographic apparatus is a copying machine or a printer, the image exposure light 4 is reflected or transmitted from the original, or the original is read by a sensor and converted into a signal, and the signal is emitted according to the signal. The light is irradiated by scanning of a laser beam, driving of an LED array, driving of a liquid crystal shutter array, and the like.

Hereinafter, the present invention will be described in more detail with reference to examples. Note that “parts” indicates “parts by weight”.

(Example 1) 50 parts of conductive titanium oxide powder coated with tin oxide containing 10% antimony oxide on an aluminum cylinder, and phenol resin 25
Parts, 30 parts of methyl cellosolve, 30 parts of methanol and silicone oil (polydimethylsiloxane polyoxyalkylene copolymer, weight average molecular weight 3,000) 0.0
The conductive layer paint prepared by dispersing 02 parts in a sand mill using 1 mmφ glass beads for 2 hours was applied by dip coating, and dried at 140 ° C. for 30 minutes to obtain a film thickness of 20 parts.
A μm conductive layer was formed.

Next, 10 parts of an alcohol-soluble copolymerized nylon resin (weight average molecular weight of 29,000) and 10 parts of methoxymethylated 6 nylon resin (weight average molecular weight of 32,000)
A solution prepared by dissolving 30 parts in a mixed solvent of 260 parts of methanol and 40 parts of butanol was dip-coated on the conductive layer.
By drying at 0 ° C. for 10 minutes, an undercoat layer having a thickness of 1 μm was formed.

Next, 4 parts of a disazo pigment represented by the following formula as a charge generating material was added to a solution prepared by dissolving 2 parts of polyvinyl benzal (degree of benzalization: 80%, weight average molecular weight: 10,000) in 30 parts of cyclohexanone. 1mm
After dispersing for 20 hours in a sand mill using φ glass beads, 60 parts of methyl ethyl ketone was added to prepare a dispersion for the charge generation layer. This dispersion was applied onto the undercoat layer by dip coating and dried at 80 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.30 μm.

[0068]

[Outside 27]

Next, as the charge transporting material, the above-mentioned fluorene compound No. 1 was used. CT-4 and 10 parts of the exemplified hindered phenol compound No. 0.7 parts of HP-1 and 10 parts of polycarbonate (weight average molecular weight 46,000) were combined with 20 parts of dichloromethane and 5 parts of monochlorobenzene.
By dip coating a solution dissolved in 0 parts of the mixed solvent on the charge generation layer and drying at 120 ° C. for 60 minutes,
A charge transport layer having a thickness of 20 μm was formed.

The electrophotographic photoreceptor thus prepared was applied to a laser beam printer (trade name: LPB-S).
X, manufactured by Canon), and the dark area potential (V
d) is charged to −700 V, and a wavelength of 80
By irradiating a laser beam of 2 nm, the bright portion potential (Vl) becomes -2.
The amount of light required to reach 00 V was measured and defined as sensitivity. Further, the variation amounts ΔVd and ΔVl of the dark portion potential and the bright portion potential after the image repetition durability test was repeated for 60,000 sheets.
Was measured and the image was visually evaluated. Note that ΔV
Positive values of d and ΔV1 indicate that the absolute value of the potential has increased, and negative values indicate that the absolute value of the potential has decreased.

Further, a so-called transfer memory | V _d1 | − | V _d2 | was measured, where V _{d1 is} the dark portion potential when the transfer current is OFF and V _d2 is the dark portion potential when the transfer current is ON.

Table 1 shows the obtained results.

(Examples 2 to 9) An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the amounts of the fluorene compound, the hindered phenol compound and the hindered phenol compound were changed as shown in Table 1. did.

Table 1 shows the results.

(Comparative Examples 1 to 9) Electrophotographic photosensitive members were prepared and evaluated in the same manner as in Examples 1 to 9 except that the hindered phenol compound was not used.

Table 1 shows the results.

[0077]

[Table 1]

(Example 10) On an aluminum cylinder, 10 parts of conductive titanium oxide powder coated with tin oxide,
Non-conductive titanium oxide powder 10 parts, phenol resin 10
Part, methyl cellosolve 10 parts, methanol 10 parts and silicone oil (polydimethylsiloxane boroxyalkylene copolymer, weight average molecular weight 3,000) 0.0
The conductive layer paint prepared by dispersing 01 parts by a sand mill apparatus using 1 mmφ glass beads for 4 hours was dip-coated and dried at 140 ° C. for 30 minutes to obtain a film thickness of 1 part.
A 5 μm conductive layer was formed.

Next, 10 parts of an alcohol-soluble copolymerized nylon resin (weight average molecular weight of 29,000) and methoxymethylated 6 nylon resin (weight average molecular weight of 32,000)
A solution prepared by dissolving 30 parts in a mixed solvent of 260 parts of methanol and 40 parts of butanol was dip-coated on the conductive layer.
By drying at 0 ° C. for 10 minutes, a film thickness of 0.5 μm
Was formed.

Next, the CuKα characteristic X
9.0 of the Bragg angle (2θ ± 0.2 °) in X-ray diffraction
Oxytitanium phthalocyanine having a crystal form having characteristic peaks at °, 14.2 °, 23.9 °, and 27.1 ° (an X-ray diffraction diagram is shown in FIG. 2; hereinafter, type I oxytitanium phthalocyanine) 10 The part is polyvinyl butyral (trade name: Esrec BX-1, manufactured by Sekisui Chemical)
0 parts with a solution of 400 parts of cyclohexanone in a sand mill using 1 mmφ glass beads.
After the dispersion, the dispersion for the charge generation layer was prepared by adding 400 parts of ethyl acetate. This dispersion was dip-coated on the undercoat layer and dried at 80 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.25 μm.

Next, as the charge transport material, the above-mentioned fluorene compound No. 1 was used. CT-19 10 parts and the exemplified hindered phenol compound No. 0.3 parts of HP-12 and polycarbonate (weight average molecular weight 46,000) 10
Parts are 20 parts of dichloromethane and 5 parts of monochlorobenzene.
By dip coating a solution dissolved in 0 parts of the mixed solvent on the charge generation layer and drying at 110 ° C. for 60 minutes,
A charge transport layer having a thickness of 22 μm was formed.

The electrophotographic photoreceptor thus prepared was applied to a laser beam printer (trade name: LPB-E).
X, made by Canon) and the dark area potential is -7
It was charged to 00 V and irradiated with a laser beam having a wavelength of 780 nm to measure the amount of light required for the bright portion potential to become -150 V, and the sensitivity was measured. Further, the image formation durability test and the evaluation of the transfer memory were repeatedly performed in the same manner as in Example 1 except that this laser beam printer was used.

Table 2 shows the results.

(Examples 11 to 20) Fluorene compounds,
An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 10 except that the amount of the hindered phenol compound and the amount of the hindered phenol compound used were as shown in Table 2.

Table 2 shows the results.

Comparative Examples 10 to 20 Electrophotographic photosensitive members were prepared and evaluated in the same manner as in Examples 10 to 20, except that the hindered phenol compound was not used.

Table 2 shows the results.

[0088]

[Table 2]

Comparative Examples 21 to 24 Electrophotographic photosensitive members were prepared and evaluated in the same manner as in Example 10 except that the following Comparative CTM-1 to Comparative CTM-4 were used in place of the fluorene compound.

Table 3 shows the results.

[0091]

[Outside 28]

[0092]

[Table 3]

(Examples 21 to 26) Electrophotographic photosensitive members were prepared and evaluated in the same manner as in Examples 10 and 14, except that oxytitanium phthalocyanine having a crystal form shown in Table 4 was used as a charge generation material. .

Table 5 shows the results.

[0095]

[Table 4]

Comparative Examples 25 to 30 Electrophotographic photosensitive members were prepared and evaluated in the same manner as in Examples 21 to 26 except that the hindered phenol compound was not used.

Table 5 shows the results.

[0098]

[Table 5]

(Example 27) A conductive layer and an undercoat layer were formed on an aluminum cylinder in the same manner as in Example 10.

Next, 8 parts of I-type oxytitanium phthalocyanine as a charge generating material and 2 parts of a disazo pigment represented by the following formula, 10 parts of polyvinyl butyral (trade name: ESLEC BX-1, manufactured by Sekisui Chemical) and 400 parts of cyclohexanone Was dispersed in a sand mill using 1 mmφ glass beads for 4 hours together with the solution dissolved in the above, and 400 parts of ethyl acetate was added to prepare a dispersion for the charge generation layer.
This dispersion was dip-coated on the undercoat layer,
By drying for 0 minutes, a charge generation layer having a thickness of 0.25 μm was formed.

[0101]

[Outside 29]

Next, as the charge transporting material, the above-mentioned fluorene compound No. 1 was used. CT-19 10 parts and the exemplified hindered phenol compound No. HP-12 0.5 part and polycarbonate (weight average molecular weight 46,000) 10
Parts are 20 parts of dichloromethane and 5 parts of monochlorobenzene.
By dip coating a solution dissolved in 0 parts of the mixed solvent on the charge generation layer and drying at 110 ° C. for 60 minutes,
A charge transport layer having a thickness of 22 μm was formed.

The thus prepared electrophotographic photosensitive member was evaluated in the same manner as in Example 10.

Table 6 shows the results.

Comparative Example 31 An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 27 except that the hindered phenol compound was not used.

Table 6 shows the results.

[0107]

[Table 6]

[0108]

As described above, according to the present invention, it has both excellent electrophotographic properties and excellent repetition durability,
Further, an electrophotographic photosensitive member that does not easily generate a transfer memory, a process cartridge having the electrophotographic photosensitive member, and an electrophotographic apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a schematic configuration of an electrophotographic apparatus including a process cartridge having an electrophotographic photosensitive member according to the present invention.

FIG. 2 is a view showing an X-ray diffraction pattern of type I oxytitanium phthalocyanine.

FIG. 3 is a view showing an X-ray diffraction pattern of A-type oxytitanium phthalocyanine.

FIG. 4 is a view showing an X-ray diffraction pattern of B-type oxytitanium phthalocyanine.

FIG. 5 is a view showing an X-ray diffraction pattern of Y-type oxytitanium phthalocyanine.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Norihiro Kikuchi 3-30-2 Shimomaruko, Ota-ku, Tokyo Within Canon Inc. (72) Inventor Kazunari Nakamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Kyano Inc.

Claims (9)

[Claims] 1. An electrophotographic photosensitive member having a photosensitive layer on a support, wherein the photosensitive layer has the following formula (1). (Wherein, R ₁ , R ₂ , R ₃ and R ₄ are the same or different and each represents a substituted or unsubstituted aryl group, and R ₅ and R ₆ are the same or different and represent a hydrogen atom, a substituted or unsubstituted An alkyl group, a substituted or unsubstituted aryl group,
And a substituted or unsubstituted aralkyl group. An electrophotographic photoreceptor comprising a fluorene compound and a hindered phenol compound represented by the following formula: 2. The electrophotographic photoreceptor according to claim 1, wherein the hindered phenol compound has a structure having a substituent at at least one of an ortho position of a hydroxyl group and an alkoxy group directly bonded to a benzene ring. 3. The electrophotographic photoreceptor according to claim 2, wherein the substituent contained in the hindered phenol compound is at least one of a substituted or unsubstituted alkyl group and a substituted or unsubstituted aralkyl group. 4. The photosensitive layer has a charge generation layer and a charge transport layer, and the charge transport layer contains a fluorene compound represented by the formula (1) and a hindered phenol compound.
4. The electrophotographic photosensitive member according to any one of items 1 to 3. 5. The electrophotographic photosensitive member according to claim 4, wherein the electrophotographic photosensitive member has a support, a charge generation layer and a charge transport layer in this order. 6. The electrophotographic photosensitive member according to claim 1, wherein the photosensitive layer contains oxytitanium phthalocyanine as a charge generating material. 7. An oxytitanium phthalocyanine comprising Cu
Bragg angle in Kα characteristic X-ray diffraction (2θ ± 0.2
°) 9.0 °, 14.2 °, 23.9 ° and 27.1.
The electrophotographic photoreceptor according to claim 6, which has a crystal form having a characteristic peak at °. 8. A process cartridge which integrally supports an electrophotographic photosensitive member and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means and is detachable from an electrophotographic apparatus main body. The photoreceptor has a photosensitive layer on a support, and the photosensitive layer has the following formula (1): (Wherein, R ₁ , R ₂ , R ₃ and R ₄ are the same or different and each represents a substituted or unsubstituted aryl group, and R ₅ and R ₆ are the same or different and represent a hydrogen atom, a substituted or unsubstituted A fluorene compound represented by an alkyl group, a substituted or unsubstituted aryl group and a substituted or unsubstituted aralkyl group) and a hindered phenol compound. 9. An electrophotographic photoreceptor, charging means, exposure means,
In an electrophotographic apparatus having a developing unit and a transfer unit, the electrophotographic photosensitive member has a photosensitive layer on a support, and the photosensitive layer has the following formula (1). (Wherein, R ₁ , R ₂ , R ₃ and R ₄ are the same or different and each represents a substituted or unsubstituted aryl group, and R ₅ and R ₆ are the same or different and represent a hydrogen atom, a substituted or unsubstituted An alkyl group, a substituted or unsubstituted aryl group and a substituted or unsubstituted aralkyl group). And a hindered phenol compound.