JP6512866B2 - Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus - Google Patents

Description

  The present invention relates to an electrophotographic photosensitive member, a process cartridge having the electrophotographic photosensitive member, and an electrophotographic apparatus.

  At present, the electrophotographic photosensitive member is generally a function separation type laminated photosensitive member in which a charge generating function and a charge transporting function are respectively divided into a charge generating layer and a charge transporting layer.

  As a charge generation material having a charge generation function, since the oscillation wavelength of a semiconductor laser often used as an image exposure means is as long as 650 to 820 nm, a charge generation material having high sensitivity to light of these long wavelengths Development is underway.

  Phthalocyanine pigments are used as charge generating materials because they have high sensitivity to light in such a long wavelength region. Among them, oxytitanium phthalocyanine and gallium phthalocyanine particularly have excellent sensitivity characteristics to light in a long wavelength region, and various crystal forms and improved production methods have been reported so far.

  Patent Document 1 discloses a hydroxygallium phthalocyanine crystal containing a polar organic solvent. In this patent document 1, by using a polar organic solvent such as N, N-dimethylformamide as a conversion solvent, conversion solvent molecules are taken into the crystal, and a crystal having excellent sensitivity characteristics is obtained.

  On the other hand, as the charge transport layer sharing the charge transport function, when the charge transport layer is the outermost surface layer as well as the charge transport function, less discharge deterioration is required. Therefore, development of resins and additives has been promoted for the purpose of improving gas resistance to gases such as ozone and nitrogen oxides generated by discharge.

  Patent Documents 2 to 4 describe that gas resistance is improved by containing an amine compound having a specific structure in the charge transport layer.

  In Patent Documents 5 to 7, gas resistance is improved by containing a charge generation substance having a specific structure in the charge generation layer and containing a charge transport substance having a specific structure and an amine compound having a specific structure in the charge transport layer. There is a statement to the effect.

Japanese Patent Laid-Open No. 7-331107 Unexamined-Japanese-Patent No. 03-172852 Unexamined-Japanese-Patent No. 2004-258253 Unexamined-Japanese-Patent No. 2010-210802 Japanese Patent Application Laid-Open No. 10-282696 JP, 2002-311607, A JP 2002-333731 A

  From the viewpoint of achieving higher image quality and higher durability in recent years, it is required to suppress the ghost phenomenon even when used repeatedly under various environments for a long time. Among various environments, it is a low temperature and low humidity environment that the ghost phenomenon is particularly likely to occur. In addition, even in the case of long-term repeated use, the ghost phenomenon may easily occur after printing an image with a high printing rate continuously.

  However, in the inventions described in Patent Documents 1 to 7 described above, the effect of suppressing the ghost phenomenon was not sufficient under severe conditions after printing an image with high printing ratio continuously in a low temperature and low humidity environment.

  An object of the present invention is to provide an electrophotographic photosensitive member in which image deterioration due to a ghost phenomenon in a low temperature and low humidity environment is suppressed, and a process cartridge and an electrophotographic apparatus having the above electrophotographic photosensitive member.

The present invention relates to an electrophotographic photosensitive member comprising a support, a charge generation layer formed on the support , and a charge transport layer formed on the charge generation layer, wherein the charge generation layer comprises at least N-methyl. formamide, containing phthalocyanine crystals containing N- propyl formamide, and any one of the amide compounds of N- vinylformamide, and charge transport layer contains a compound represented by the following formula (1), the in the charge generation layer, the content of the amide compound contained in the phthalocyanine crystals, relative to the content of phthalocyanine of the phthalocyanine crystal, Ru der 0.1 wt% 3.0 wt% or less An electrophotographic photoreceptor characterized by:

[In formula (1), R ¹ and X ¹ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted heterocyclic group, Or R ¹ and X ¹ represent a group necessary to bond to each other to form a nitrogen-containing heterocycle, Ar ¹ is a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted Represents a heterocyclic group. ].

  Further, the present invention is a process cartridge detachably mountable to an electrophotographic apparatus main body, the electrophotographic photosensitive member, and at least one device selected from the group consisting of a charging device, a developing device, and a cleaning device. And the electrophotographic photosensitive member and at least one device selected from the group consisting of the charging device, the developing device, and the cleaning device are integrally supported. It is a cartridge.

  Further, the present invention is an electrophotographic apparatus comprising the above electrophotographic photosensitive member, and a charging unit, an image exposing unit, a developing unit, and a transfer unit.

  According to the present invention, it is possible to provide an electrophotographic photosensitive member in which image deterioration due to a ghost phenomenon in a low temperature and low humidity environment is suppressed, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

FIG. 1 is a view showing an example of a schematic configuration of an electrophotographic apparatus provided with a process cartridge having the electrophotographic photosensitive member of the present invention. It is a powder X-ray-diffraction figure of the hydroxygallium phthalocyanine crystal obtained in Example 1-1. It is a powder X-ray diffraction pattern of the hydroxygallium phthalocyanine crystal obtained in Example 1-5. It is a powder X-ray-diffraction figure of the hydroxygallium phthalocyanine crystal obtained in Example 1-6. It is a powder X-ray diffraction pattern of the chlorogallium phthalocyanine crystal obtained in Example 1-8. It is a NMR spectrum of the hydroxygallium phthalocyanine crystal obtained in Example 1-1. It is an NMR spectrum of the hydroxygallium phthalocyanine crystal obtained in Comparative Example 1-1.

<Electrophotographic photosensitive member>
As described above, the electrophotographic photosensitive member of the present invention has a support, and the charge generation layer and charge transport layer formed on the support.

  The charge generation layer contains gallium phthalocyanine crystals containing at least one amide compound selected from the group consisting of N-methylformamide, N-propylformamide and N-vinylformamide.

  Furthermore, the charge transport layer contains a compound represented by the following formula (1).

In formula (1), R ¹ and X ¹ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted heterocyclic group, or And R ¹ and X ¹ represent an atomic group necessary to bond to each other to form a nitrogen-containing heterocyclic ring. Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted heterocyclic group.

  The present inventors speculate as follows about the reason why the electrophotographic photosensitive member of the present invention is excellent in the effect of suppressing the occurrence of the ghost phenomenon.

  The electrophotographic photosensitive member of the present invention comprises, in the charge generation layer, at least one amide compound selected from the group consisting of N-methylformamide, N-propylformamide, and N-vinylformamide, and the charge transport layer It contains the compound shown by (1). By including the gallium phthalocyanine crystal in the charge generation layer, and containing the amide compound in the charge transport layer, the flow of photocarriers from the charge generation layer to the charge transport layer is improved, and the retention of photocarriers in the charge generation layer The present inventors think that it suppresses. Therefore, it is considered that even when used under a low temperature and low humidity environment, it is possible to suppress the ghost phenomenon caused by the retention of the photo carrier.

  Among the compounds represented by the above formula (1), any of the compounds represented by the following formulas (2) to (4) is preferable because image deterioration due to the ghost phenomenon can be further suppressed.

In formulas (2) to (4), R ^2a , R ^2b and R ^{3 to} R ⁵ each independently represent a substituted or unsubstituted alkyl group. Ar ^{2 to} Ar ⁵ each independently represent a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted heterocyclic group. Each of X ^2a , X ^2b and X ^{3 to} X ⁶ independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted heterocyclic group. The total carbon number of the alkyl group is 1 or more and 20 or less, the total carbon number of the aromatic hydrocarbon group is 6 or more and 20 or less, and the total carbon number of the heterocyclic group is 4 or more and 20 or less.

Among the compounds represented by the above formula (2), X ^2a and X ^2b are each independently a substituted or unsubstituted aromatic hydrocarbon group, and the total carbon number of the aromatic hydrocarbon group is 6 or more It is preferable that it is 20 or less because image deterioration due to the ghost phenomenon can be suppressed. In addition, it is preferable that X ^2a and X ^2b have the same structure, because image deterioration due to the ghost phenomenon can be suppressed. Further, it is preferable that R ^2a and R ^2b have the same structure, because image deterioration due to the ghost phenomenon can be suppressed.

Among the compounds represented by the above formula (3), it is preferable that X ³ be the following formula (5) because image deterioration due to the ghost phenomenon can be further suppressed.

[In formula (5), Ar ⁶ represents a substituted or unsubstituted aromatic hydrocarbon group and may be the same as or different from Ar ³ and Ar ⁴ . The total carbon number of the aromatic hydrocarbon group is 6 or more and 20 or less. ]

Among the compounds represented by the above formula (4), X ^{4 to} X ⁶ are substituted or unsubstituted aromatic hydrocarbon groups, and the total carbon number of the aromatic hydrocarbon groups is 6 or more and 20 or less Further, it is preferable because the image deterioration due to the ghost phenomenon can be further suppressed.

Examples of the alkyl group of R ¹ , R ^2a , R ^2b and R ^{3 to} R ^{5 in} the above formulas (1) to (4) include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, a decanyl group and the like It can be mentioned. In addition, the alkyl group may be a cycloalkyl group or a heterocycloalkyl group. Examples of the cycloalkyl group include cyclopropyl group, cyclobutyl group, cyclopentyl group and cyclohexyl group. As the heterocycloalkyl group, those in which at least one carbon atom of the above-mentioned cyclohexyl group is substituted by an oxygen atom, a sulfur atom, a nitrogen atom or the like can be mentioned. Examples of the substituent include an alkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, a halogen group and the like. These substituents may further have other substituents.

Examples of the aromatic hydrocarbon group of Ar ^{1 to} Ar ^{5 in} the above formulas (1) to (4) include a phenyl group, a biphenyl group, a naphthyl group, an antonyl group and a pyrenyl group. Further, Ar ^{1 to} Ar ⁵ may be a heterocyclic group in which a carbon atom in an aromatic ring of an aromatic hydrocarbon group is substituted with an oxygen atom, a sulfur atom, a nitrogen atom or the like. Examples of the substituent include an alkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, a halogen group and the like. These substituents may further have other substituents. In addition, as an alkyl group, it is preferable that it is a C1-C4 alkyl group. The aryl group is preferably a phenyl group or a naphthyl group.

As the alkyl group of X ¹ , X ^2a , X ^2b and X ^{3 to} X ^{6 in} the above formulas (1) to (4), a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, a decanyl group, etc. It can be mentioned. In addition, the alkyl group may be a cycloalkyl group or a heterocycloalkyl group. Examples of the cycloalkyl group include cyclopropyl group, cyclobutyl group, cyclopentyl group and cyclohexyl group. As the heterocycloalkyl group, those in which at least one carbon atom of the above-mentioned cyclohexyl group is substituted by an oxygen atom, a sulfur atom, a nitrogen atom or the like can be mentioned.

The aromatic hydrocarbon group represented by X ¹ , X ^2a , X ^2b , X ^{3 to} X ⁶ and R ^{1 in} the above formulas (1) to (4) is a phenyl group, a biphenyl group, a naphthyl group, an anthnyl group, a pyrenyl group Groups and the like. In addition, X ¹ , X ^2a , X ^2b , X ^{3 to} X ⁶ and R ^{1 each} represent a heterocyclic group in which a carbon atom in the aromatic ring of the aromatic hydrocarbon group is substituted with an oxygen atom, a sulfur atom, a nitrogen atom or the like It may be Examples of the substituent include an alkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, a halogen group and the like. These substituents may further have other substituents. In addition, as an alkyl group, it is preferable that it is a C1-C4 alkyl group. The aryl group is preferably a phenyl group or a naphthyl group.

  The total carbon number of the alkyl group, the aromatic hydrocarbon group, or the heterocyclic group refers to the total number of carbon atoms configured. When it has a substituent, the number of carbon atoms of the substituent is added to the number of carbon atoms of the skeleton. For example, the total carbon number of the phenyl group substituted by the methyl group is seven.

  Specific examples (exemplified compounds (1) to (92)) of the compound represented by the above formula (1) are shown below.

  The compounds represented by the above-mentioned exemplified compounds (12), (69) and (89) by formulas (2) to (4) are shown below for reference.

  A plurality of compounds represented by the above formula (1) contained in the charge transport layer according to the present invention may be used. The content of the compound represented by the formula (1) in the charge transport layer is preferably 0.01% by mass or more and 20% by mass or less based on the binder resin contained in the charge transport layer, and 0.1% by mass It is more preferable that it is% or more and 5 mass% or less. When a plurality of compounds represented by the formula (1) are used, the content of the compound represented by the formula (1) in the charge transport layer described above means the total content of the compounds represented by the formula (1). Do.

  It is preferable that content of the said amide compound contained in a gallium phthalocyanine crystal is 0.1 mass% or more and 3.0 mass% or less with respect to content of the gallium phthalocyanine in the said gallium phthalocyanine crystal. Moreover, it is more preferable that it is 0.1 to 1.9 mass%. When the content of the amide compound is in the above range, the image deterioration due to the ghost phenomenon can be further suppressed.

  A plurality of amide compounds of N-methylformamide, N-propylformamide and N-vinylformamide contained in the gallium phthalocyanine crystal according to the present invention may be used. When a plurality of amide compounds are used, the content of the amide compound means the total content of the amide compounds.

  In addition, from the viewpoint of suppressing image deterioration due to the ghost phenomenon, the amide compound according to the present invention is preferably N-methylformamide. This is because N-methylformamide has high compatibility with gallium phthalocyanine, so it is easy to be incorporated into the crystal, and it is particularly easy to polarize, thus further improving the retention of charge causing the ghost phenomenon. It is thought that it is because it can do.

  Among the gallium phthalocyanine crystals according to the present invention, a hydroxygallium phthalocyanine crystal having excellent sensitivity (a gallium atom having a hydroxy group as an axial ligand), a chlorogallium phthalocyanine crystal (a gallium atom as an axial ligand, a chlorine atom) Those having a), bromogallium phthalocyanine crystals (in which a gallium atom has a bromine atom as an axial ligand), and iodogallium phthalocyanine crystals (wherein a gallium atom having an iodine atom as an axial ligand) are preferable. Among them, hydroxygallium phthalocyanine crystals and chlorogallium phthalocyanine crystals are more preferable.

  Furthermore, in the case of a hydroxygallium phthalocyanine crystal, it is a hydroxygallium phthalocyanine crystal having peaks at 7.4 ° ± 0.3 ° and 28.3 ° ± 0.3 ° at Bragg angle 2θ in X-ray diffraction of CuKα ray Is particularly preferred in view of high sensitivity.

  In the case of chlorogallium phthalocyanine crystals, chlorogallium having peaks at 7.4 °, 16.6 °, 25.5 ° and 28.3 ° at Bragg angle 2θ ± 0.2 ° in X-ray diffraction of CuKα ray The phthalocyanine crystal is particularly preferred in view of high sensitivity.

  A method of producing gallium phthalocyanine crystals containing an amide compound such as N-methylformamide, N-propylformamide, and N-vinylformamide in the crystal will be described.

  The gallium phthalocyanine crystal containing the amide compound according to the present invention in the crystal can be obtained by milling using a solvent containing the amide compound in the step of crystal conversion of gallium phthalocyanine by wet milling.

  The hydroxygallium phthalocyanine used for the milling treatment is preferably hydroxygallium phthalocyanine obtained by an acid pasting method.

  The chlorogallium phthalocyanine used for the milling treatment is preferably chlorogallium phthalocyanine obtained by mixing the hydroxygallium phthalocyanine obtained by the acid pasting method with an aqueous solution of hydrochloric acid.

  The milling treatment performed here is, for example, a treatment performed using a milling apparatus such as a sand mill or a ball mill together with a dispersing agent such as glass beads, steel beads, or alumina balls. The milling time is preferably about 30 to 3000 hours. A particularly preferred method is to take a sample every 10 to 100 hours and confirm the content of the amide compound in the gallium phthalocyanine crystal by NMR measurement. The amount of dispersant used in the milling treatment is preferably 10 to 50 times that of gallium phthalocyanine on a mass basis.

  The amount of the organic compound used is preferably 5 to 30 times that of the gallium phthalocyanine crystal on a mass basis.

  In the present invention, whether or not the gallium phthalocyanine crystal contains the amide compound in the crystal was determined by NMR measurement of the obtained gallium phthalocyanine crystal.

  In the present invention, measurement of X-ray diffraction and NMR of a gallium phthalocyanine crystal contained in an electrophotographic photosensitive member is conducted under the following conditions.

[Powder X-ray diffraction measurement]
Measuring instrument used: manufactured by Rigaku Denki Co., Ltd., X-ray diffractometer RINT-TTRII
X-ray tube: Cu
Tube voltage: 50KV
Tube current: 300mA
Scanning method: 2θ / θ scan Scanning speed: 4.0 ° / min
Sampling interval: 0.02 °
Start angle (2θ): 5.0 °
Stop angle (2θ): 40.0 °
Attachment: Standard sample holder Filter: Not used Incident monochrome: Used Counter monochromator: Not used Divergence slit: Open Divergence Vertical restriction slit: 10.00 mm
Scattering slit: Open Light receiving slit: Open Flat plate monochromator: Used Counter: Scintillation counter.

[NMR measurement ( ¹ H-NMR measurement)]
Measuring instrument: BRUKER, AVANCE III 500
Measurement nuclide: ¹ H
Solvent: Heavy sulfuric acid (D ₂ SO ₄ )
Number of integrations: 2000.

  The photosensitive layer of the electrophotographic photosensitive member of the present invention is a laminated photosensitive layer in which a charge generation layer and a charge transport layer are laminated. In addition, the charge generation layer is the lower layer in the lamination relationship between the charge generation layer and the charge transport layer.

[Support]
The support used in the present invention may be any one having conductivity (conductive support). Specific examples thereof include metals and alloys such as aluminum and stainless steel, metals provided with a conductive layer, alloys, plastics and paper, and examples of the shape include cylindrical and film shapes.

[Subbing layer]
In the present invention, an undercoat layer (also referred to as an intermediate layer) having a barrier function and an adhesive function may be provided between the support and the photosensitive layer.

  As a constituent material of the undercoat layer, binder resins such as polyvinyl alcohol, polyethylene oxide, ethyl cellulose, methyl cellulose, casein, polyamide, glue and gelatin are used. These are dissolved in a suitable solvent and coated on a support. Moreover, a metal oxide may be added as a resistance control agent.

  The thickness of the undercoat layer is preferably 0.3 to 5.0 μm.

[Conductive layer]
Furthermore, a conductive layer may be provided between the support and the undercoat layer for covering unevenness and defects of the support and for preventing interference fringes.

  The conductive layer can be formed by dispersing conductive particles such as carbon black, metal particles, and metal oxides in a binder resin.

  The thickness of the conductive layer is preferably 5 to 40 μm, and more preferably 10 to 30 μm.

[Charge generation layer]
When forming the charge generation layer, first, the gallium phthalocyanine crystal according to the present invention is dispersed in a solvent together with the binder resin to prepare a coating liquid for charge generation layer. Then, a coating film of the coating solution for charge generation layer is formed, and the obtained coating film is dried to form a charge generation layer.

  The thickness of the charge generation layer is preferably 0.05 to 1 μm, and more preferably 0.1 to 0.3 μm.

  The content of the gallium phthalocyanine crystal containing the amide compound in the charge generation layer is preferably 40% by mass to 85% by mass, and more preferably 60% by mass to 80% by mass, with respect to the total mass of the charge generation layer. It is more preferable that

  Examples of the binder resin used for the charge generation layer include resins such as polyester, acrylic resin, polycarbonate, polyvinyl butyral, polystyrene, polyvinyl acetate, polysulfone, acrylonitrile copolymer and polyvinyl benzal. Among these, polyvinyl butyral and polyvinyl benzal are preferable as the resin for dispersing the gallium phthalocyanine crystal.

[Charge transport layer]
The charge transport layer is formed by applying a coating liquid for charge transport layer in which a compound represented by the formula (1), a charge transport substance (charge transport material) and a binder resin are dissolved in a solvent, It can form by drying the obtained coating film. In addition, a release agent for increasing the transfer efficiency of the toner, a fingerprint adhesion preventing agent for preventing dirt, a filler for preventing abrasion, and lubricity of the surface of the electrophotographic photosensitive member are increased in the charge transport layer. You may use a lubricant for this purpose.

  The thickness of the charge transport layer is preferably 5 to 40 μm, and more preferably 10 to 25 μm.

  The content of the compound represented by the formula (1) in the charge transport layer is preferably 0.01% by mass to 40% by mass with respect to the total mass of the charge transport layer, and is preferably 0.1% by mass to 10%. It is more preferable that the content is at most mass%.

  The content of the charge transport substance is preferably 20 to 80% by mass, particularly preferably 30 to 60% by mass, based on the total mass of the charge transport layer.

  Examples of the charge transport material include various triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, thiazole compounds and triallylmethane compounds. Among these, triarylamine compounds are preferable as the charge transport material. One or a combination of two or more of the charge transport materials can be used.

  Examples of the binder resin used for the charge transport layer include resins such as polyester, acrylic resin, phenoxy resin, polycarbonate, polysulfone, polyarylate, and acrylonitrile copolymer. Among these, polycarbonate and polyarylate are preferable. A combination of one or more of these resins can be used.

  The content of the charge transport substance is preferably 20 to 80% by mass, particularly preferably 30 to 60% by mass, based on the total mass of the charge transport layer.

  Examples of the charge transport material include various triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, thiazole compounds and triallylmethane compounds. Among these, triarylamine compounds are preferable as the charge transport material.

  As a coating method of each layer, coating methods such as dip coating (dipping), spray coating, spinner coating, bead coating, blade coating, and beam coating can be used.

<Process cartridge and electrophotographic apparatus>
FIG. 1 is a view showing an example of a schematic configuration of an electrophotographic apparatus provided with a process cartridge having the electrophotographic photosensitive member of the present invention.

  In FIG. 1, a cylindrical (drum-like) electrophotographic photosensitive member 1 is rotationally driven around an axis 2 in the arrow direction at a predetermined peripheral speed (process speed).

  The surface of the electrophotographic photosensitive member 1 is charged by the charging unit 3 to a predetermined positive or negative potential in the rotation process. Next, image exposure light 4 is irradiated from the image exposure means (not shown) on the charged surface of the electrophotographic photosensitive member 1, and an electrostatic latent image corresponding to the target image information is formed. The image exposure light 4 is, for example, light which is intensity-modulated corresponding to the time-series electric digital image signal of the target image information, which is output from an image exposure means such as slit exposure or laser beam scanning exposure.

  The electrostatic latent image formed on the surface of the electrophotographic photoreceptor 1 is developed (normal development or reversal development) with the toner contained in the developing means 5, and a toner image is formed on the surface of the electrophotographic photoreceptor 1 Be done. The toner image formed on the surface of the electrophotographic photosensitive member 1 is transferred to the transfer material 7 by the transfer means 6. At this time, a bias voltage having a polarity opposite to that of the toner's stored charge is applied to the transfer means 6 from a bias power supply (not shown). When the transfer material 7 is paper, the transfer material 7 is taken out of the paper feed unit (not shown) and synchronized with the rotation of the electrophotographic photosensitive member 1 between the electrophotographic photosensitive member 1 and the transfer means 6. Is fed.

  The transfer material 7 to which the toner image has been transferred from the electrophotographic photosensitive member 1 is separated from the surface of the electrophotographic photosensitive member 1 and is conveyed to the image fixing means 8 and subjected to the fixing process of the toner image to form an image. It is printed out of the electrophotographic apparatus as an object (print, copy).

  The surface of the electrophotographic photosensitive member 1 after the toner image is transferred to the transfer material 7 is cleaned by the cleaning means 9 by removing the extraneous matter such as toner (transfer residual toner). In recent years, a cleanerless system has also been developed, and transfer residual toner can be directly removed by a developing device or the like. Furthermore, after the surface of the electrophotographic photosensitive member 1 is subjected to charge removal processing by the pre-exposure light 10 from the pre-exposure means (not shown), it is repeatedly used for image formation. When the charging unit 3 is a contact charging unit using a charging roller or the like, the pre-exposure unit is not necessarily required.

  In the present invention, among the components such as the electrophotographic photosensitive member 1, the charging unit 3, the developing unit 5 and the cleaning unit 9 described above, a plurality of components are housed in a container and integrally supported to form a process cartridge. . Then, the process cartridge can be detachably configured to the electrophotographic apparatus main body. For example, the electrophotographic photosensitive member 1 and at least one selected from the charging unit 3, the developing unit 5 and the cleaning unit 9 are integrally supported to form a cartridge. Then, the process cartridge 11 can be detachably attached to the electrophotographic apparatus main body by using the guide means 12 such as a rail of the electrophotographic apparatus main body.

  When the electrophotographic apparatus is a copying machine or a printer, the image exposure light 4 may be reflected light or transmitted light from an original. Alternatively, it may be light emitted by scanning a laser beam, driving an LED array, driving a liquid crystal shutter array, or the like in accordance with this signal by reading an original by a sensor, and making a signal.

  The electrophotographic photosensitive member 1 of the present invention can be widely applied to electrophotographic application fields such as laser beam printer, CRT printer, LED printer, FAX, liquid crystal printer and laser plate making.

  Hereinafter, the present invention will be described in more detail by way of specific examples. However, the present invention is not limited to these. In addition, the film thickness of each layer of the electrophotographic photosensitive member of the example and the comparative example is determined by an eddy current film thickness meter (Fischerscope, manufactured by Fisher Instruments Co., Ltd.), or determined from specific mass conversion per unit area. The Moreover, "part" as described in the following means "mass part", and "%" means "mass%."

<Synthesis of Gallium Phthalocyanine Pigment>
Synthesis Example 1-1
Under an atmosphere of nitrogen flow, 5.46 parts of phthalonitrile and 45 parts of α-chloronaphthalene were charged into the reaction kettle and then heated to a temperature of 30 ° C., and this temperature was maintained. Next, 3.75 parts of gallium trichloride were charged at this temperature (30 ° C.). The water content of the mixture at the time of feeding was 150 ppm. Thereafter, the temperature was raised to 200.degree. Next, after reacting for 4.5 hours at a temperature of 200 ° C. under an atmosphere of nitrogen flow, it was cooled and the product was filtered when the temperature reached 150 ° C. The obtained filtrate was dispersed and washed with N, N-dimethylformamide at a temperature of 140 ° C. for 2 hours and then filtered. The obtained filtrate was washed with methanol and then dried to obtain 4.65 parts (yield 71%) of a chlorogallium phthalocyanine pigment.

Synthesis Example 1-2
4.65 parts of the chlorogallium phthalocyanine pigment obtained in Synthesis Example 1-1 is dissolved in 139.5 parts of concentrated sulfuric acid at a temperature of 10.degree. C., dropped into 620 parts of ice water with stirring, and reprecipitated to obtain a filter. Filtered using a press. The obtained wet cake (filtered material) was dispersed and washed with 2% aqueous ammonia, and then filtered using a filter press. Next, the obtained wet cake (filtered product) was dispersed and washed with ion-exchanged water, and then filtration using a filter press was repeated three times to obtain a hydrous hydroxygallium phthalocyanine pigment having a solid content of 23%.

Synthesis Example 1-3
Ten parts of the hydrous hydroxygallium phthalocyanine pigment obtained in Synthesis Example 1-2 and 200 parts of a hydrochloric acid aqueous solution having a concentration of 35% by mass and a temperature of 23 ° C. were mixed, and stirred at room temperature with a magnetic stirrer for 90 minutes. The mixed amount of the aqueous hydrochloric acid solution was 118 mol of hydrochloric acid to 1 mol of hydroxygallium phthalocyanine. After stirring, this dispersion solution was dropped into 1000 parts of ion-exchanged water cooled with ice water, and stirred with a magnetic stirrer for another 30 minutes. Then, the obtained dispersion was filtered under reduced pressure. At this time, as a filter, No. 5C (manufactured by Advantec) was used. Thereafter, dispersion washing was performed four times with ion exchange water at a temperature of 23 ° C. Thus, 9 parts of chlorogallium phthalocyanine pigment was obtained. This chlorogallium phthalocyanine pigment is a crystalline form having peaks at a Bragg angle 2θ of 7.1 °, 16.6 °, 25.7 °, 27.4 ° and 28.3 ° in CuKα characteristic X-ray diffraction. there were.

Examples 1-1 to 1-8 and Comparative Examples 1-1 to 1-4>
Example 1-1
0.5 part of the hydroxygallium phthalocyanine pigment obtained in Synthesis Example 1-2 and 9.5 parts of N-methylformamide are ball milled together with 15 parts of glass beads having a diameter of 0.8 mm at room temperature (23 ° C.) I went down for 600 hours. At this time, the container was a standard bottle (product code: PS-6, manufactured by Toyo Glass), and the container was rotated at 60 revolutions per minute. After 30 parts of tetrahydrofuran was added to the dispersion thus obtained, it was filtered through a filter, and the filtered residue remaining on the filter was thoroughly washed with tetrahydrofuran. Then, the washed product was dried under vacuum to obtain 0.45 parts of hydroxygallium phthalocyanine crystals. The powder X-ray diffraction pattern of the obtained crystals is shown in FIG.

  Further, it is confirmed by NMR measurement that N-methylformamide is contained in an amount of 0.9% by mass with respect to hydroxygallium phthalocyanine in the crystal, as converted from the proton ratio, in the obtained hydroxygallium phthalocyanine crystal. The Since N-methylformamide is compatible with tetrahydrofuran, it is known that N-methylformamide is present in the crystals. The NMR spectrum of the obtained hydroxygallium phthalocyanine crystal is shown in FIG.

Example 1-2
A hydroxygallium phthalocyanine crystal was obtained in the same manner as in Example 1-1 except that the milling treatment time was changed from 600 hours to 2000 hours in Example 1-1. The powder X-ray diffraction pattern of the obtained crystals was the same as in FIG.

  Further, it is confirmed by NMR measurement that, in the obtained hydroxygallium phthalocyanine crystal, 0.6 mass% of N-methylformamide is contained with respect to hydroxygallium phthalocyanine in the crystal, as converted from the proton ratio. The

Example 1-3
In Example 1-1, a hydroxygallium phthalocyanine crystal was obtained in the same manner as in Example 1-1 except that the milling treatment time was changed from 600 hours to 100 hours. The powder X-ray diffraction pattern of the obtained crystals was the same as in FIG.

  In addition, it is confirmed by NMR measurement that the obtained hydroxygallium phthalocyanine crystal contains 2.1% by mass of N-methylformamide relative to hydroxygallium phthalocyanine in the crystal, as converted from the proton ratio. The

Example 1-4
A hydroxygallium phthalocyanine crystal was obtained in the same manner as in Example 1-1 except that the milling treatment time was changed from 600 hours to 200 hours in Example 1-1. The powder X-ray diffraction pattern of the obtained crystals was the same as in FIG.

  Further, it is confirmed by NMR measurement that the obtained hydroxygallium phthalocyanine crystal contains 1.7% by mass of N-methylformamide relative to hydroxygallium phthalocyanine in the crystal, as converted from the proton ratio. The

[Example 1-5]
Processed in the same manner as in Example 1-1 except that in Example 1-1, 9.5 parts of N-methylformamide was replaced by 9.5 parts of N-vinylformamide, and the milling time was changed from 600 hours to 200 hours. To obtain hydroxygallium phthalocyanine crystals. The powder X-ray diffraction pattern of the obtained crystals is shown in FIG.

  Further, it is confirmed by NMR measurement that the obtained hydroxygallium phthalocyanine crystal contains 1.8% by mass of N-vinylformamide relative to hydroxygallium phthalocyanine in the crystal, as converted from the proton ratio. The

[Example 1-6]
Example 1-1 is the same as example 1-1 except that 9.5 parts of N-methylformamide is replaced with 9.5 parts of N-n-propylformamide, and the milling time is changed from 600 hours to 200 hours. To obtain hydroxygallium phthalocyanine crystals. The powder X-ray diffraction pattern of the obtained crystals is shown in FIG.

  Moreover, it is converted from a proton ratio in the obtained hydroxygallium phthalocyanine crystal by NMR measurement, and it is 2.4 mass% that N-n- propyl formamide is contained with respect to the hydroxygallium phthalocyanine in crystal | crystallization. confirmed.

[Example 1-7]
The same treatment as in Example 1-6 was carried out except that the milling treatment time was changed from 200 hours to 1000 hours in Example 1-6, to obtain a hydroxygallium phthalocyanine crystal. The powder X-ray diffraction pattern of the obtained crystals was the same as in FIG.

  Moreover, it is converted from a proton ratio in the obtained hydroxygallium phthalocyanine crystal by NMR measurement, and 1.4 mass% of N-n-propylformamide is contained with respect to the hydroxygallium phthalocyanine in crystal | crystallization. confirmed.

[Example 1-8]
In Example 1-1, 0.5 part of the hydroxygallium phthalocyanine pigment obtained in Synthesis Example 1-2 is replaced with 0.5 part of the chlorogallium phthalocyanine pigment obtained in Synthesis Example 1-3, and the milling time is 600 The same treatment as in Example 1-1 was carried out except that time was changed to 200 hours, to obtain 0.46 parts of chlorogallium phthalocyanine crystals. The powder X-ray diffraction pattern of the obtained crystals is shown in FIG.

  Further, it is confirmed by NMR measurement that 0.4% by mass of N-methylformamide is contained in the obtained chlorogallium phthalocyanine crystal, as converted from the proton ratio, with respect to chlorogallium phthalocyanine in the crystal. The

Comparative Example 1-1
In Example 1-1, 0.5 part of the hydroxygallium phthalocyanine pigment obtained in Synthesis Example 1-2, 9.5 parts of N-methylformamide, and 15 parts of glass beads having a diameter of 0.8 mm are used instead of Synthesis Example 1 Example 2 except using 1.25 parts of the hydroxygallium phthalocyanine pigment obtained in -2, 9.5 parts of N, N-dimethylformamide, 25 parts of glass beads having a diameter of 5 mm, and setting the milling time to 48 hours It was treated in the same manner as -1 to obtain 1.14 parts of hydroxygallium phthalocyanine crystal.

  Moreover, it is converted from a proton ratio in the obtained hydroxygallium phthalocyanine crystal by NMR measurement, and 2.1 mass% of N, N-dimethylformamide is contained with respect to the hydroxygallium phthalocyanine in crystal | crystallization. confirmed. The NMR spectrum of the obtained hydroxygallium phthalocyanine crystal is shown in FIG.

Comparative Example 1-2
Example 1-1 is the same as example 1-1 except that 9.5 parts of N-methylformamide is replaced with 9.5 parts of N, N-dimethylformamide and the milling time is changed from 600 hours to 100 hours. To obtain 0.43 parts of hydroxygallium phthalocyanine crystal.

  Moreover, it is converted from a proton ratio in the obtained hydroxygallium phthalocyanine crystal by NMR measurement, and 2.1 mass% of N, N-dimethylformamide is contained with respect to the hydroxygallium phthalocyanine in crystal | crystallization. confirmed.

Comparative Example 1-3
A hydroxygallium phthalocyanine crystal was obtained in the same manner as in Comparative Example 1-2 except that, in Comparative Example 1-2, 9.5 parts of N, N-dimethylformamide was replaced with 9.5 parts of dimethyl sulfoxide.

  Further, it was confirmed by NMR measurement that dimethylsulfoxide was contained in the obtained hydroxygallium phthalocyanine crystal in an amount of 2.4% by mass relative to hydroxygallium phthalocyanine in the crystal, as converted from the proton ratio.

Comparative Example 1-4
A hydroxygallium phthalocyanine crystal is treated in the same manner as in Comparative Example 1-2 except that 9.5 parts of N, N-dimethylformamide is replaced with 9.5 parts of N-methyl-2-pyrrolidone in Comparative Example 1-2. I got

  In addition, it is converted from a proton ratio in the obtained hydroxygallium phthalocyanine crystal by NMR measurement, and 2.9 mass% of N-methyl-2-pyrrolidone is contained with respect to hydroxygallium phthalocyanine in the crystal. Was confirmed.

Examples 2-1 to 2-26, and Comparative Examples 2-1 to 2-4>
Example 2-1
60 parts of barium sulfate particles coated with tin oxide (trade name: Pastelan PC1, manufactured by Mitsui Kinzoku Mining Co., Ltd.), 15 parts of titanium oxide particles (trade name: TITANIX JR, manufactured by Tayca Corporation), resol type phenol resin ( Brand name: Phenolite J-325, manufactured by DIC Ltd., solid content 70% by mass, 43 parts, silicone oil (trade name: SH28PA, manufactured by Toray Dow Corning Co., Ltd.) 0.015 parts, silicone resin Name: Tospearl 120, 3.6 parts of Momentive Performance Material Co., Ltd., 50 parts of 2-methoxy-1-propanol and 50 parts of methanol are dispersed by a ball mill for 20 hours to obtain a conductive layer. A coating solution was prepared.

  The coating solution for a conductive layer was dip-coated on an aluminum cylinder as a support, and the obtained coating film was dried at 140 ° C. for 30 minutes to form a conductive layer having a thickness of 15 μm.

  Next, 10 parts of copolymerized nylon resin (trade name: Amilan CM 8000, manufactured by Toray Industries, Inc.) and 30 parts of methoxymethylated 6 nylon resin (trade name: Toresin EF-30T, manufactured by Nagase ChemteX Co., Ltd.) An undercoat layer coating solution was prepared by dissolving in a mixed solvent of 400 parts of methanol / 200 parts of n-butanol.

  The undercoat layer coating liquid was dip-coated on the conductive layer, and the obtained coating film was dried to form an undercoat layer having a thickness of 0.7 μm.

  Next, 10 parts of hydroxygallium phthalocyanine crystal (charge generating material) obtained in Example 1-1, 5 parts of polyvinyl butyral (trade name: S-Lec BX-1, manufactured by Sekisui Chemical Co., Ltd.), and cyclohexanone 250 A part was placed in a sand mill using glass beads having a diameter of 1 mm, dispersed for 6 hours, and 250 parts of ethyl acetate was added thereto to dilute, thereby preparing a coating solution for charge generation layer.

  The coating solution for charge generation layer was dip-coated on the undercoat layer, and the obtained coating film was dried at 100 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.22 μm.

  Next, 28 parts of a compound (charge transporting substance) represented by the following formula (CTM-1), 4 parts of a compound (charge transporting substance) represented by the following formula (CTM-2), 1 part of exemplified compound (1), polycarbonate A coating solution for charge transport layer was prepared by dissolving 40 parts of (trade name: Iupilon Z200, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) in a mixed solvent of 200 parts of monochlorobenzene and 50 parts of dimethoxymethane.

  The coating solution for charge transport layer was dip-coated on the charge generation layer, and the obtained coated film was dried at 125 ° C. for 1 hour to form a charge transport layer having a thickness of 23 μm.

  Thus, a cylindrical (drum-like) electrophotographic photosensitive member of Example 2-1 was produced.

Example 2-2
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the hydroxygallium phthalocyanine crystal obtained in Example 1-2. In addition, the exemplary compound (1) at the time of preparing the coating liquid for charge transport layer was changed to the exemplary compound (12). An electrophotographic photosensitive member of Example 2-2 was produced in the same manner as in Example 2-1 except for these changes.

Example 2-3
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the hydroxygallium phthalocyanine crystal obtained in Example 1-3. In addition, the exemplary compound (1) at the time of preparing the coating solution for charge transport layer was changed to the exemplary compound (7). An electrophotographic photosensitive member of Example 2-3 was produced in the same manner as in Example 2-1 except for these changes.

Example 2-4
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the hydroxygallium phthalocyanine crystal obtained in Example 1-4. In addition, the exemplary compound (1) at the time of preparing the coating solution for charge transport layer was changed to the exemplary compound (5). An electrophotographic photosensitive member of Example 2-4 was produced in the same manner as in Example 2-1 except for these changes.

[Example 2-5]
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the hydroxygallium phthalocyanine crystal obtained in Example 1-5. In addition, the exemplary compound (1) at the time of preparing the coating liquid for charge transport layer was changed to the exemplary compound (13). Except for these changes, an electrophotographic photosensitive member of Example 2-5 was produced in the same manner as in Example 2-1.

Example 2-6
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the hydroxygallium phthalocyanine crystal obtained in Example 1-6. In addition, the exemplary compound (1) at the time of preparing the coating solution for charge transport layer was changed to the exemplary compound (14). An electrophotographic photosensitive member of Example 2-6 was produced in the same manner as in Example 2-1 except for these changes.

Example 2-7
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the hydroxygallium phthalocyanine crystal obtained in Example 1-2. In addition, the exemplary compound (1) at the time of preparing the coating liquid for charge transport layer was changed to the exemplary compound (6). An electrophotographic photosensitive member of Example 2-7 was produced in the same manner as in Example 2-1 except for these changes.

[Example 2-8]
The same procedure as in Example 2-1 is followed, except that, in Example 2-1, the exemplified compound (1) at the time of preparing the coating liquid for charge transport layer is changed to the exemplified compound (15). An electrophotographic photosensitive member was produced.

[Example 2-9]
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the chlorogallium phthalocyanine crystal obtained in Example 1-8. In addition, the exemplary compound (1) at the time of preparing the coating liquid for charge transport layer was changed to the exemplary compound (16). An electrophotographic photosensitive member of Example 2-9 was produced in the same manner as in Example 2-1 except for these changes.

Example 2-10
The same procedure as in Example 2-1 is followed, except that, in Example 2-1, the exemplified compound (1) in preparing the coating solution for charge transport layer is changed to the exemplified compound (22). An electrophotographic photosensitive member was produced.

[Example 2-11]
Example 2-1 Example 2-11 in the same manner as Example 2-1 except that Exemplified Compound (1) in preparing the coating solution for charge transport layer in Example 2-1 was changed to Exemplified compound (23). An electrophotographic photosensitive member was produced.

[Example 2-12]
Example 2-1 Example 2-12 in the same manner as Example 2-1 except that Exemplified Compound (1) in preparing the coating solution for charge transport layer in Example 2-1 was changed to Exemplified compound (41). An electrophotographic photosensitive member was produced.

[Example 2-13]
The same procedure as in Example 2-1 is followed, except that, in Example 2-1, the exemplified compound (1) in preparing the coating solution for charge transport layer is changed to the exemplified compound (42). An electrophotographic photosensitive member was produced.

[Example 2-14]
The procedure of Example 2-14 is the same as that of Example 2-1 except that, in Example 2-1, Exemplified compound (1) at the time of preparing the coating liquid for charge transport layer is changed to Exemplified compound (45). An electrophotographic photosensitive member was produced.

[Example 2-15]
The same procedure as in Example 2-1 is followed, except that, in Example 2-1, the exemplified compound (1) in preparing the coating solution for charge transport layer is changed to the exemplified compound (40). An electrophotographic photosensitive member was produced.

[Example 2-16]
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the chlorogallium phthalocyanine crystal obtained in Example 1-8. In addition, the exemplary compound (1) at the time of preparing the coating liquid for charge transport layer was changed to the exemplary compound (49). Except for these changes, an electrophotographic photosensitive member of Example 2-16 was produced in the same manner as in Example 2-1.

[Example 2-17]
The same procedure as in Example 2-1 is followed, except that, in Example 2-1, the exemplified compound (1) at the time of preparing the coating liquid for charge transport layer is changed to the exemplified compound (50). An electrophotographic photosensitive member was produced.

[Example 2-18]
The procedure of Example 2-18 is the same as that of Example 2-1 except that, in Example 2-1, Exemplified Compound (1) at the time of preparing the coating liquid for charge transport layer is changed to Exemplified Compound (67). An electrophotographic photosensitive member was produced.

[Example 2-19]
The same procedure as in Example 2-1 is followed, except that, in Example 2-1, the exemplified compound (1) at the time of preparing the coating solution for charge transport layer is changed to the exemplified compound (56). An electrophotographic photosensitive member was produced.

[Example 2-20]
The same procedure as in Example 2-1 is followed, except that, in Example 2-1, Exemplified Compound (1) in preparing the coating solution for charge transport layer is changed to the exemplified compound (55). An electrophotographic photosensitive member was produced.

Example 2-21
The procedure of Example 2-21 is the same as that of Example 2-1 except that, in Example 2-1, Exemplified Compound (1) at the time of preparing the coating liquid for charge transport layer is changed to Exemplified Compound (52). An electrophotographic photosensitive member was produced.

Example 2-22
The same procedure as in Example 2-1 is followed, except that, in Example 2-1, the exemplified compound (1) at the time of preparing the coating liquid for charge transport layer is changed to the exemplified compound (26). An electrophotographic photosensitive member was produced.

[Example 2-23]
The same procedure as in Example 2-1 is followed, except that, in Example 2-1, Exemplified Compound (1) at the time of preparing the coating liquid for charge transport layer is changed to the exemplified compound (34). An electrophotographic photosensitive member was produced.

[Example 2-24]
The procedure of Example 2-24 is the same as that of Example 2-1 except that, in Example 2-1, Exemplified compound (1) at the time of preparing the coating liquid for charge transport layer is changed to Exemplified compound (89). An electrophotographic photosensitive member was produced.

[Example 2-25]
The same procedure as in Example 2-1 is followed, except that, in Example 2-1, the exemplified compound (1) in preparing the coating solution for charge transport layer is changed to the exemplified compound (92). An electrophotographic photosensitive member was produced.

[Example 2-26]
In Example 2-1, 4 parts of the compound (charge transporting substance) represented by (CTM-2) in preparation of the coating liquid for charge transport layer is changed to 4 parts of exemplified compound (12), and an exemplified compound (1 Did not add). Except for these changes, an electrophotographic photosensitive member of Example 2-26 was produced in the same manner as in Example 2-1.

Comparative Example 2-1
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the hydroxygallium phthalocyanine crystal obtained in Comparative Example 1-1. Moreover, the exemplary compound (1) at the time of preparing the coating liquid for charge transport layers was not added. An electrophotographic photosensitive member of Comparative Example 2-1 was produced in the same manner as in Example 2-1 except for these changes.

Comparative Example 2-2
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the hydroxygallium phthalocyanine crystal obtained in Comparative Example 1-2. Moreover, the exemplary compound (1) at the time of preparing the coating liquid for charge transport layers was not added. An electrophotographic photosensitive member of Comparative Example 2-2 was produced in the same manner as in Example 2-1 except for these changes.

[Comparative example 2-3]
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the hydroxygallium phthalocyanine crystal obtained in Comparative Example 1-3. Moreover, the exemplary compound (1) at the time of preparing the coating liquid for charge transport layers was not added. An electrophotographic photosensitive member of Comparative Example 2-3 was produced in the same manner as in Example 2-1 except for these changes.

Comparative Example 2-4
In Example 2-1, the hydroxygallium phthalocyanine crystal obtained in Example 1-1 when preparing the coating liquid for charge generation layer was changed to the hydroxygallium phthalocyanine crystal obtained in Comparative Example 1-4. Moreover, the exemplary compound (1) at the time of preparing the coating liquid for charge transport layers was not added. An electrophotographic photosensitive member of Comparative Example 2-4 was produced in the same manner as in Example 2-1 except for these changes.

[Evaluation of Examples 2-1 to 2-26 and Comparative Examples 2-1 to 2-4]
With respect to the electrophotographic photosensitive members of Examples 2-1 to 2-26 and Comparative Examples 2-1 to 2-4, the ghost phenomenon in the output image after repeated use was evaluated.

  As an electrophotographic apparatus for evaluation, a laser beam printer (trade name: Color Laser Jet M451 dn) manufactured by Nippon Hewlett Packard Co., Ltd. was used after being subjected to the following modification. First, the charging conditions and the image exposure amount were made variable. Further, the electrophotographic photosensitive member manufactured as described above was attached to a process cartridge for cyan and attached to a station of the process cartridge for cyan. In addition, the process cartridge for other colors (magenta, yellow, black) is operated without being attached to the printer body.

  First, under the normal temperature and normal humidity environment of temperature 23 ° C./humidity 55% RH, charging conditions and image exposure such that the dark area potential of the electrophotographic photosensitive member of Example 2-1 becomes −500 V and the light area potential becomes −80 V Adjusted the amount. The measurement of the surface potential of the electrophotographic photosensitive member was as follows. First, the process cartridge is remodeled, and a potential probe (trade name: model 6000B-8, manufactured by Trek Japan Ltd.) is mounted at the development position. Thereafter, the potential at the central portion of the cylindrical electrophotographic photosensitive member was measured using a surface voltmeter (trade name: model 344, manufactured by Trek Japan Ltd.).

  Thereafter, the electrophotographic photosensitive member was left for 3 days in an environment of low temperature and low humidity of 15 ° C./10% RH together with an electrophotographic apparatus for evaluation, and then a ghost image was evaluated. Under the same conditions (low temperature and low humidity environment), 1000 sheets were repeatedly subjected to paper-passing tests, and ghost images were evaluated immediately after the repetition of the paper-passing test and 15 hours after the repetition of the paper-passing test.

  The repeated sheet passing test was conducted under the condition that an E-letter image with a printing rate of 20% was printed on plain paper of A4 size in cyan single color. The evaluation results are shown in Table 2.

  Moreover, the method of ghost image evaluation is as follows.

  In the ghost image evaluation, a solid white image is output on the first sheet, and then four ghost charts are output, one for each of four types. Next, after one solid black image is output, a total of four sheets of ghost charts are output again, one for each of four types. Images were output in this order, and evaluated using a total of eight ghost images. In the ghost chart, first, a range of 30 mm from the position of the output image writing (paper upper end 10 mm) is arranged in parallel on a solid white background with 25 mm square solid black squares equally spaced and in parallel. And the thing of the printing pattern of the halftone of following (1)-(4) was respectively used after 30 mm from an output image write-in position.

That is, the four types of ghost charts are charts that differ only in the halftone pattern after 30 mm from the output image writing position, and the halftone is the following four types.
(1) Horizontal ^* 1 dot, 1 space printing (laser exposure) pattern.
(2) Horizontal ^* 2 dots, 2 spaces printing (laser exposure) pattern.
(3) Horizontal ^* 2 dots, 3 spaces printing (laser exposure) pattern.
(4) Printing (laser exposure) pattern of Keima pattern. (A pattern that prints 2 dots on 6 squares like the movement of Shoma's Keima)
*: “Horizontal” refers to the scanning direction of the laser scanner (horizontal direction for the output sheet).

The ghost images were classified as follows. In the ranks 4, 5, and 6, it was determined that the effects of the present invention were not sufficiently obtained.
Rank 1: No ghost is visible in any ghost chart.
Rank 2: A ghost is visible in a specific ghost chart.
Rank 3: Ghosts are faintly visible in any ghost chart.
Rank 4: Ghosts are visible on certain ghost charts.
Rank 5: Ghosts are visible on any ghost chart.
Rank 6: Ghosts are clearly visible in certain ghost charts.

DESCRIPTION OF SYMBOLS 1 electrophotographic photosensitive member 2 axis 3 Charging means 4 Image exposure light 5 Development means 6 Transfer means 7 Transfer material 8 Image fixing means 9 Cleaning means 10 Pre-exposure light 11 Process cartridge 12 Guide means

Claims (11)

Support, a charge generation layer formed on the support, and an electrophotographic photosensitive member having a charge transport layer charge formed on the generating layer,
The charge generation layer contains a gallium phthalocyanine crystal containing at least one amide compound of N-methylformamide, N-propylformamide, and N-vinylformamide, and the charge transport layer has the following formula (1) Containing the compound shown in
The content of the amide compound contained in the gallium phthalocyanine crystal in the charge generation layer is 0.1% by mass or more and 3.0% by mass or less with respect to the content of gallium phthalocyanine in the gallium phthalocyanine crystal. Electrophotographic photoreceptors characterized by:

[In formula (1), R ¹ and X ¹ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted heterocyclic group, Or R ¹ and X ¹ represent a group necessary to bond to each other to form a nitrogen-containing heterocycle, Ar ¹ is a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted Represents a heterocyclic group. ]. The charge transport layer contains a binder resin,
The electrophotographic photosensitive member according to claim 1, wherein a content of the compound represented by the formula (1) is 0.1% by mass or more and 5% by mass or less with respect to the content of the binder resin. The electrophotographic photosensitive member according to claim 1 or 2 , wherein the compound represented by the formula (1) is any one of compounds represented by the following formulas (2) to (4):



[In the formulas (2) to (4), R ^2a , R ^2b and R ^{3 to} R ⁵ each independently represent a substituted or unsubstituted alkyl group, and Ar ^{2 to} Ar ⁵ each independently represent And a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted heterocyclic group, wherein X ^2a , X ^2b and X ^{3 to} X ⁶ each independently represent a substituted or unsubstituted alkyl group, Represents a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted heterocyclic group. The total carbon number of the alkyl group is 1 or more and 20 or less, the total carbon number of the aromatic hydrocarbon group is 6 or more and 20 or less, and the total carbon number of the heterocyclic group is 4 or more and 20 or less. ]. In the above formula (2), X ^2a and X ^2b are each independently a substituted or unsubstituted aromatic hydrocarbon group, and the total carbon number of the aromatic hydrocarbon group is 6 or more and 20 or less. Item 4. An electrophotographic photosensitive member according to item 3 . The electrophotographic photosensitive member according to claim 3 , wherein in the formula (3), X ³ is the following formula (5):

[In formula (5), Ar ⁶ represents a substituted or unsubstituted aromatic hydrocarbon group and may be the same as or different from Ar ³ and Ar ⁴ . The total carbon number of the aromatic hydrocarbon group is 6 or more and 20 or less. ]. In the above formula (4), X ^{4 to} X ⁶ each independently represent a substituted or unsubstituted aromatic hydrocarbon group, and the total carbon number of the aromatic hydrocarbon group is 6 or more and 20 or less. Item 4. An electrophotographic photosensitive member according to item 3 . The content of the amide compound contained in the gallium phthalocyanine crystal in the charge generation layer is 0.1% by mass or more and 1.9% by mass or less based on the content of gallium phthalocyanine in the gallium phthalocyanine crystal. An electrophotographic photosensitive member according to any one of items 1 to 6 .   The electrophotographic photosensitive member according to any one of claims 1 to 7, wherein the amide compound is N-methyl formamide.   The electrophotographic photosensitive member according to any one of claims 1 to 8, wherein the gallium phthalocyanine crystal is a hydroxygallium phthalocyanine crystal or a chlorogallium phthalocyanine crystal.   An electrophotographic apparatus main body integrally supporting the electrophotographic photosensitive member according to any one of claims 1 to 9 and at least one unit selected from the group consisting of a charging unit, a developing unit, and a cleaning unit. Process cartridge that is removable from the   An electrophotographic apparatus comprising the electrophotographic photosensitive member according to any one of claims 1 to 9, and a charging unit, an exposure unit, a developing unit and a transfer unit.