JP6485135B2 - Image forming method, image forming apparatus, and process cartridge - Google Patents

Description

  The present invention relates to an image forming method, an image forming apparatus, and a process cartridge.

  An electrophotographic image forming apparatus generally has the following configuration and process. That is, the surface of the electrophotographic photosensitive member is charged to polarity and potential, and the surface of the charged electrophotographic photosensitive member is selectively neutralized by image exposure to form an electrostatic latent image, and then the electrostatic latent image is formed. By applying toner to the image, the latent image is developed as a toner image, and the toner image is transferred to a recording medium to be discharged as an image formed product.

  In recent years, an electrophotographic photosensitive member has an advantage that high-speed and high printing quality can be obtained, so that it is increasingly used in fields such as a copying machine and a laser beam printer.

  As electrophotographic photoreceptors used in these image forming apparatuses, conventional electrophotographic photoreceptors (inorganic photoreceptors) using inorganic photoconductive materials such as selenium, selenium-tellurium alloys, selenium-arsenic alloys, and cadmium sulfide are known. In recent years, organic photoreceptors (organic photoreceptors) using organic photoconductive materials, which are inexpensive and have excellent advantages in terms of manufacturability and disposal, have come to dominate.

  In order to increase the life and reliability of the electrophotographic photosensitive member, it has been proposed to improve the strength by providing a protective layer on the surface of the electrophotographic photosensitive member.

The following materials have been proposed as a material system for forming the protective layer.
That is, for example, Patent Document 1 includes a conductive powder dispersed in a phenol resin, Patent Document 2 includes an organic-inorganic hybrid material, and Patent Document 3 includes an alcohol-soluble charge transport material and a phenol resin. Are disclosed respectively.
Patent Document 4 discloses a cured film of an alkyl etherated benzoguanamine / formaldehyde resin and an electron-accepting carboxylic acid or an electron-accepting polycarboxylic acid anhydride, and Patent Document 5 discloses a benzoguanamine resin containing iodine, A cured film doped with an organic sulfonic acid compound or ferric chloride is disclosed in Patent Document 6 as a cured film of a specific additive and a phenol resin, melamine resin, benzoguanamine resin, siloxane resin, or urethane resin. Is disclosed as a protective layer.

In recent years, a protective layer made of an acrylic material has attracted attention. For example, Patent Document 7 discloses a film obtained by curing a liquid containing a photocurable acrylic monomer, and Patent Document 8 discloses a monomer having a carbon-carbon double bond and a charge transfer having a carbon-carbon double bond. A film formed by reacting a carbon-carbon double bond of the monomer and a carbon-carbon double bond of the charge transfer material with a mixture of a material and a binder resin by heat or light energy is disclosed in Patent Literature Nos. 9 and 10 each disclose a film made of a compound obtained by polymerizing a hole transporting compound having two or more chain polymerizable functional groups in the same molecule as a protective layer. Patent Document 11 discloses an electrophotographic photoreceptor using a film made of a compound obtained by polymerizing a styryl group-modified hole transporting compound.
Since these hole-transporting compounds having a chain polymerizable functional group are strongly affected by curing conditions, curing atmosphere, etc., for example, Patent Document 12 discloses heating in a vacuum or inert gas after irradiation with radiation. Patent Document 13 discloses a film formed by heating and curing in an inert gas.
Further, for example, Patent Documents 8 and 14 disclose that the charge transport material itself is acrylic-modified to be crosslinkable, and a reactive monomer having no charge transport property is added to improve the film strength. ing.

Furthermore, the following things are proposed as a protective layer by a reaction material and a cured film.
For example, Patent Document 15 discloses a protective layer containing a compound obtained by modifying the charge transport material itself into a polyfunctional compound having three or more functions and polymerizing the same. Patent Document 16 discloses a technique in which a polymer of a charge transport material having a chain polymerizable functional group is used for a protective layer, and also contains fluorine atoms as a lubricant in order to improve friction characteristics. A technique for containing a compound in a protective layer is disclosed. In addition, Patent Document 17 discloses that both the mechanical characteristics and the electrical characteristics can be achieved by increasing the concentration of the charge transport material having a chain polymerizable functional group from the outermost surface toward the inside.

  Patent Document 18 discloses a first charge transporting compound having one or more chain polymerizable functional groups and a chain polymerizable property of 5.0 to 45.0 wt% with respect to the first charge transporting compound. The inclusion of a second charge transporting compound having no functional group is disclosed. Patent Document 19 discloses that a first charge transporting compound having at least an acryloyloxy group or a methacryloyloxy group and a second charge transporting compound having a hydroxyl group are contained. Patent Document 20 discloses that the same low molecular charge transport material as that of the charge transport layer is further contained in the cross-linked charge transport layer.

  In Patent Document 21, Patent Document 22, and Non-Patent Document 1, zinc stearate is supplied to a photoreceptor having a cross-linked structure on the surface, solid lubricant such as boron nitride, and aluminum oxide. It has been disclosed that the maintainability of an image is improved by including a suitable abrasive in zinc stearate.

  Further, Patent Document 23 discloses an image forming method using a photoreceptor having a crosslinked structure on the surface and a toner containing a fatty acid metal salt having a median diameter of 0.10 μm or more and 1.00 μm or less.

  Patent Document 24 discloses the wear rate of a photoreceptor whose surface layer is made of polycarbonate and the content of zinc stearate in the toner.

  Patent Document 25 discloses an example in which a photoconductor on the surface of a crosslinked film having a specific structure and a metal soap such as zinc stearate are added to the toner. Patent Document 26 discloses a photoconductor on the surface of a cross-linked film having a specific structure. And a method of controlling the zinc stearate coverage on the surface of the photoreceptor after printing is disclosed.

Japanese Patent No. 3287678 Japanese Patent Laid-Open No. 12-019749 JP 2002-82469 A Japanese Patent Laid-Open No. 62-251757 Japanese Patent Laid-Open No. 7-146564 JP 2006-84711 A JP-A-5-40360 JP-A-5-216249 JP 2000-206715 A JP 2001-166509 A Japanese Patent No. 2852464 Japanese Patent Laid-Open No. 2004-12986 Japanese Patent Laid-Open No. 7-72640 JP 2004-302450 A JP 2000-206717 A JP 2001-175016 A JP 2007-86522 A Japanese Patent Laid-Open No. 2005-62301 Japanese Patent Laid-Open No. 2005-62302 Japanese Patent Laid-Open No. 2006-13895 JP 2007-79244 A JP 2012-123209 A JP 2010-54884 A JP 2007-310181 A JP 2013-44820 A JP 2013-105046 A

Ricoh Technical Report No. 38, p. 37

  An object of the present invention is to provide a cured film of a composition containing a reactive charge transport material, and an electrophotographic photosensitive member by charging means disposed in contact with or in close proximity to the surface of the electrophotographic photosensitive member having an outermost surface layer. A developer containing a toner having a charging step of charging the surface of the toner, an electrostatic latent image forming step of forming an electrostatic latent image on the surface of the charged electrophotographic photosensitive member, and toner particles and fatty acid metal salt particles, The developing process for developing the electrostatic latent image formed on the surface of the electrophotographic photosensitive member to form a toner image, the transferring step for transferring the toner image to the surface of the recording medium, and the surface of the electrophotographic photosensitive member In the image forming method through the cleaning step of cleaning the surface of the electrophotographic photosensitive member with a cleaning blade, any one of formula (A1), formula (B1), formula (B2), formula (C1), and formula (C2) Meet Compared to the case where the outermost surface layer is composed of a cured film of a composition containing one kind of reactive charge transport material having the same molecular structure, in a high temperature / high humidity environment or a low temperature / low humidity environment, An object of the present invention is to provide an image forming method capable of obtaining an image in which density unevenness is suppressed over a long period of time even when an image having a high image density is repeatedly formed.

  The above problem is solved by the following means.

The invention according to < 1 >
A cured film of a composition comprising a conductive substrate and a photosensitive layer provided on the conductive substrate, and comprising two or more reactive charge transport materials, or a reactive charge transport material and a charge transport skeleton The surface of the electrophotographic photosensitive member is charged by charging means disposed in contact with or in close proximity to the surface of the electrophotographic photosensitive member having the outermost surface layer, which is a cured film of a composition containing a reactive material that does not react. Charging process,
An electrostatic latent image forming step of forming an electrostatic latent image on the surface of the charged electrophotographic photosensitive member;
A developing step of developing the electrostatic latent image formed on the surface of the electrophotographic photosensitive member with a developer including toner having toner particles and fatty acid metal salt particles to form a toner image;
A transfer step of transferring the toner image to the surface of the recording medium;
A cleaning step of cleaning the surface of the electrophotographic photosensitive member with a cleaning blade in contact with the surface of the electrophotographic photosensitive member;
Have
The content of the fatty acid metal salt particles with respect to the total mass of the toner is Rmf (mass%),
When an image including three types of image patterns having different image densities is repeatedly formed in a high-temperature and high-humidity environment, the average wear rate of the electrophotographic photosensitive member is Wh (nm / 1000 rotations), and the maximum wear of the electrophotographic photosensitive member is The rate is Whmax (nm / 1000 rotations), the minimum wear rate of the electrophotographic photosensitive member is Whmin (nm / 1000 rotations),
When an image including three types of image patterns having different image densities is repeatedly formed in a low-temperature and low-humidity environment, the average wear rate of the electrophotographic photoreceptor is Wl (nm / 1000 rotations), and the maximum wear rate of the electrophotographic photoreceptor is Is Wlmax (nm / 1000 rotations), and the minimum wear rate of the electrophotographic photosensitive member is Wlmin (nm / 1000 rotations),
An image forming method that satisfies the following formula (A1), the following formula (B1), the following formula (B2), the following formula (C1), and the following formula (C2).
Formula (A1): 0.01 <Rmf <0.20
Formula (B1): 0.005 <Rmf / Wh <5.000
Formula (B2): 0.002 <Rmf / Wl <1.000
Formula (C1): 1.0 <Whmax / Whmin <2.5
Formula (C2): 1.0 <Wlmax / Wlmin <2.5

The invention according to < 2 >
< 1 > The image forming method according to < 1 > , wherein the fatty acid metal salt particles are zinc stearate particles having a median diameter on a volume basis of 0.1 μm to 10.0 μm.

The invention according to < 3 >
The image forming method according to < 1 > or < 2 > , wherein the toner particles have a volume average particle size of 3.0 μm or more and 3.7 μm or less.

The invention according to < 4 >
The outermost surface layer is composed of a cured film of a composition comprising a reactive charge transporting material and a reactive material having no charge transporting skeleton;
The image according to any one of < 1 > to < 3 > , wherein the reactive material is a chain polymerizable compound that does not have a charge transporting skeleton in the same molecule and has at least a chain polymerizable functional group. Forming method.

The invention according to < 5 >
The image forming method according to any one of < 1 > to < 4 > , wherein the reactive charge transporting material is a chain polymerizable compound having at least a charge transporting skeleton and a chain polymerizable functional group in the same molecule.

The invention according to < 6 >
The image forming method according to any one of < 1 > to < 5 > , wherein the reactive charge transport material is a compound selected from chain polymerizable compounds represented by the following general formulas (I) and (II): .

[In general formula (I), F represents a charge transporting skeleton. L represents a divalent linking group containing two or more selected from the group consisting of an alkylene group, an alkenylene group, -C (= O)-, -N (R)-, -S-, and -O-. Show. R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. m represents an integer of 1 or more and 8 or less. ]

[In General Formula (II), F represents a charge transporting skeleton. L ′ represents a trivalent or tetravalent group derived from an alkane or alkene, and an alkylene group, alkenylene group, —C (═O) —, —N (R) —, —S—, and —O—. (N + 1) -valent linking groups containing two or more selected from the group consisting of: R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. m ′ represents an integer of 1 to 6. n represents an integer of 2 or more and 3 or less. ]

The invention according to < 7 >
A cured film of a composition comprising a conductive substrate and a photosensitive layer provided on the conductive substrate, and comprising two or more reactive charge transport materials, or a reactive charge transport material and a charge transport skeleton A cured film of a composition containing a reactive material that does not, an electrophotographic photosensitive member having an outermost surface layer formed thereon,
A charging means disposed in contact with or in proximity to the surface of the electrophotographic photosensitive member to charge the surface of the electrophotographic photosensitive member;
An electrostatic latent image forming means for forming an electrostatic latent image on the surface of the charged electrophotographic photosensitive member;
Developing means for containing a developer containing toner having toner particles and fatty acid metal salt particles, and developing the electrostatic latent image formed on the surface of the electrophotographic photosensitive member with the developer to form a toner image When,
Transfer means for transferring the toner image to the surface of the recording medium;
Cleaning means having a cleaning blade that contacts the surface of the electrophotographic photosensitive member and cleans the surface of the electrophotographic photosensitive member;
With
The content of the fatty acid metal salt particles with respect to the total mass of the toner is Rmf (mass%),
When an image including three types of image patterns having different image densities is repeatedly formed in a high-temperature and high-humidity environment, the average wear rate of the electrophotographic photosensitive member is Wh (nm / 1000 rotations), and the maximum wear of the electrophotographic photosensitive member is The rate is Whmax (nm / 1000 rotations), the minimum wear rate of the electrophotographic photosensitive member is Whmin (nm / 1000 rotations),
When an image including three types of image patterns having different image densities is repeatedly formed in a low-temperature and low-humidity environment, the average wear rate of the electrophotographic photoreceptor is Wl (nm / 1000 rotations), and the maximum wear rate of the electrophotographic photoreceptor is Is Wlmax (nm / 1000 rotations), and the minimum wear rate of the electrophotographic photosensitive member is Wlmin (nm / 1000 rotations),
An image forming apparatus that satisfies the following formula (A1), the following formula (B1), the following formula (B2), the following formula (C1), and the following formula (C2).
Formula (A1): 0.01 <Rmf <0.20
Formula (B1): 0.005 <Rmf / Wh <5.000
Formula (B2): 0.002 <Rmf / Wl <1.000
Formula (C1): 1.0 <Whmax / Whmin <2.5
Formula (C2): 1.0 <Wlmax / Wlmin <2.5

The invention according to < 8 >
A cured film of a composition comprising a conductive substrate and a photosensitive layer provided on the conductive substrate, and comprising two or more reactive charge transport materials, or a reactive charge transport material and a charge transport skeleton A cured film of a composition containing a reactive material that does not, an electrophotographic photosensitive member having an outermost surface layer formed thereon,
A charging means disposed in contact with or in proximity to the surface of the electrophotographic photosensitive member to charge the surface of the electrophotographic photosensitive member;
Developing means for containing a developer containing toner having toner particles and fatty acid metal salt particles, and developing the electrostatic latent image formed on the surface of the electrophotographic photosensitive member with the developer to form a toner image When,
Cleaning means having a cleaning blade that contacts the surface of the electrophotographic photosensitive member and cleans the surface of the electrophotographic photosensitive member;
With
The content of the fatty acid metal salt particles with respect to the total mass of the toner is Rmf (mass%),
When an image including three types of image patterns having different image densities is repeatedly formed in a high-temperature and high-humidity environment, the average wear rate of the electrophotographic photosensitive member is Wh (nm / 1000 rotations), and the maximum wear of the electrophotographic photosensitive member is The rate is Whmax (nm / 1000 rotations), the minimum wear rate of the electrophotographic photosensitive member is Whmin (nm / 1000 rotations),
When an image including three types of image patterns having different image densities is repeatedly formed in a low-temperature and low-humidity environment, the average wear rate of the electrophotographic photoreceptor is Wl (nm / 1000 rotations), and the maximum wear rate of the electrophotographic photoreceptor is Is Wlmax (nm / 1000 rotations), and the minimum wear rate of the electrophotographic photosensitive member is Wlmin (nm / 1000 rotations),
The following formula (A1), the following formula (B1), the following formula (B2), the following formula (C1) and the following formula (C2) are satisfied,
A process cartridge that can be attached to and detached from an image forming apparatus.
Formula (A1): 0.01 <Rmf <0.20
Formula (B1): 0.005 <Rmf / Wh <5.000
Formula (B2): 0.002 <Rmf / Wl <1.000
Formula (C1): 1.0 <Whmax / Whmin <2.5
Formula (C2): 1.0 <Wlmax / Wlmin <2.5

According to the invention according to < 1 > , by the charging means disposed in contact with or in proximity to the surface of the electrophotographic photosensitive member in which the outermost surface layer is formed in the cured film of the composition including the reactive charge transport material, A charging step for charging the surface of the electrophotographic photosensitive member; an electrostatic latent image forming step for forming an electrostatic latent image on the surface of the charged electrophotographic photosensitive member; and a toner having toner particles and fatty acid metal salt particles. A developing step of developing an electrostatic latent image formed on the surface of the electrophotographic photosensitive member with a developer to form a toner image; a transferring step of transferring the toner image onto the surface of the recording medium; In the image forming method that includes a cleaning step of cleaning the surface of the electrophotographic photosensitive member with a cleaning blade in contact with the surface, the formula (A1), the formula (B1), the formula (B2), the formula (C1), and the formula ( Izu of C2) If the outermost surface layer is composed of a cured film of a composition containing one kind of reactive charge transporting material having the same molecular structure, a low image in a high temperature and high humidity environment or a low temperature and low humidity environment. There is provided an image forming method capable of obtaining an image in which density unevenness is suppressed over a long period of time even when an image having a high density or a high density is repeatedly formed.

According to the invention according to < 2 > , a high-temperature, high-humidity environment or a low-temperature, low-humidity environment as compared with a case where the toner contains only zinc stearate particles having a volume-based median diameter exceeding 10.0 μm as fatty acid metal salt particles. Thus, there is provided an image forming method capable of obtaining an image in which density unevenness is suppressed over a long period of time even when an image having a low image density or a high image density is repeatedly formed.

According to the invention according to < 3 > , an image having a low image density or a high image density was repeatedly formed in a high-temperature and high-humidity environment or a low-temperature and low-humidity environment as compared with the case where the volume average particle diameter of the toner particles exceeds 3.7 μm. Even at times, there is provided an image forming method capable of obtaining an image in which density unevenness is suppressed over a long period of time.
According to the invention according to < 4 > , compared with the case where the outermost surface layer is composed of a cured film of a composition containing two or more kinds of reactive charge transport materials, the temperature is low in a high temperature and high humidity environment or a low temperature and low humidity environment. There is provided an image forming method capable of obtaining an image in which density unevenness is suppressed over a long period of time even when an image having a high image density or a high image density is repeatedly formed.

According to the invention according to < 5 > or < 6 > , compared with a case where an electrophotographic photosensitive member having an outermost surface layer containing only a non-reactive charge transport material is used as a charge transport material, There is provided an image forming method capable of obtaining an image in which density unevenness is suppressed over a long period of time even when an image having a low image density or a high image density is repeatedly formed in a low humidity environment.

According to the invention according to < 7 > , the cured film of the composition containing the reactive charge transport material is disposed in contact with or in proximity to the electrophotographic photosensitive member having the outermost surface layer formed thereon and the surface of the electrophotographic photosensitive member. And a toner having charging means for charging the surface of the electrophotographic photosensitive member, electrostatic latent image forming means for forming an electrostatic latent image on the surface of the charged electrophotographic photosensitive member, and toner particles and fatty acid metal salt particles. A developing means for developing the electrostatic latent image formed on the surface of the electrophotographic photosensitive member with the developer to form a toner image, and transfer for transferring the toner image to the surface of the recording medium In the image forming apparatus, comprising: a cleaning means having a cleaning blade that contacts the surface of the electrophotographic photosensitive member and cleans the surface of the electrophotographic photosensitive member, the formula (A1), the formula (B1), the formula (B2) ), Formula (C1) When the outermost surface layer is composed of a cured film of a composition containing one type of reactive charge transporting material having the same molecular structure, the temperature and humidity environment is not satisfied. Alternatively, an image forming apparatus capable of obtaining an image in which density unevenness is suppressed over a long period of time even when an image having a low image density or a high image density is repeatedly formed in a low-temperature and low-humidity environment.

According to the invention according to < 8 > , the cured film of the composition containing the reactive charge transporting material is disposed in contact with or close to the electrophotographic photosensitive member having the outermost surface layer formed thereon and the surface of the electrophotographic photosensitive member. And a charging means for charging the surface of the electrophotographic photosensitive member, and a developer containing toner having toner particles and fatty acid metal salt particles, and electrostatic particles formed on the surface of the electrophotographic photosensitive member by the developer. A process cartridge comprising: a developing unit that develops a latent image to form a toner image; and a cleaning unit that has a cleaning blade that contacts the surface of the electrophotographic photosensitive member and cleans the surface of the electrophotographic photosensitive member. A1), formula (B1), formula (B2), a cured film of a composition that does not satisfy any of formula (C1) and formula (C2), or a composition containing one kind of reactive charge transport material having the same molecular structure so Compared to the case where the surface layer is configured, even when an image having a low image density or a high image density is repeatedly formed in a high-temperature and high-humidity environment or a low-temperature and low-humidity environment, an image with reduced density unevenness can be obtained over a long period of time. A process cartridge is provided.

1 is a schematic partial cross-sectional view illustrating an example of a layer configuration of an electrophotographic photoreceptor according to an exemplary embodiment. FIG. 6 is a schematic partial cross-sectional view illustrating another example of the layer configuration of the electrophotographic photosensitive member according to the exemplary embodiment. FIG. 6 is a schematic partial cross-sectional view illustrating another example of the layer configuration of the electrophotographic photosensitive member according to the exemplary embodiment. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an exemplary embodiment. It is a schematic block diagram which shows another example of the image forming apparatus which concerns on this embodiment. It is a schematic diagram which shows an image pattern.

  Hereinafter, the present embodiment which is an example of the present invention will be described.

  The image forming method according to the present embodiment includes a charging step of charging the surface of the photoreceptor by charging means arranged in contact with or in proximity to the surface of the electrophotographic photoreceptor (hereinafter also referred to as “photoreceptor”); An electrostatic latent image forming step for forming an electrostatic latent image on the surface of the charged photoreceptor and a developer containing toner develop the electrostatic latent image formed on the surface of the photoreceptor to form a toner image. A developing step, a transfer step of transferring the toner image to the surface of the recording medium, and a cleaning step of cleaning the surface of the photoconductor with a cleaning blade in contact with the surface of the photoconductor.

  An image forming apparatus (an image forming apparatus according to this embodiment) that performs the image forming method according to the present embodiment is disposed in contact with or close to the surface of the photoconductor and the surface of the photoconductor. A charging unit for charging, an electrostatic latent image forming unit for forming an electrostatic latent image on the surface of the charged photoconductor, and a developer containing toner are accommodated, and a static image formed on the surface of the photoconductor by the developer is accommodated. A developing unit that develops the electrostatic latent image to form a toner image, a transfer unit that transfers the toner image to the surface of the recording medium, and a cleaning blade that contacts the surface of the photoconductor and cleans the surface of the photoconductor Means.

  The photosensitive member has a conductive substrate and a photosensitive layer provided on the conductive substrate, and is a cured film of a composition containing two or more kinds of reactive charge transport materials, or a reactive charge transport material and charge transport. A photoconductor having an outermost surface layer composed of a cured film of a composition containing a reactive material having no reactive skeleton (hereinafter also referred to as “curing photoconductor”). The developer includes toner having toner particles and fatty acid metal salt particles.

In the image forming method according to the present embodiment, the content of the fatty acid metal salt particles with respect to the total mass of the toner is Rmf (mass%), and an image including three types of image patterns having different image densities is displayed in a high-temperature and high-humidity environment. The average wear rate of the photoconductor is Wh (nm / 1000 rpm), the maximum wear rate of the photoconductor is Whmax (nm / 1000 rpm), and the minimum wear rate of the photoconductor is Whmin (nm / 1000 rpm). ), And when an image including three types of image patterns having different image densities is repeatedly formed in a low-temperature and low-humidity environment, the average wear rate of the photoconductor is Wl (nm / 1000 rotations), and the maximum wear rate of the photoconductor is Wlmax ( nm / 1000 rpm), and the minimum wear rate of the photoreceptor is Wlmin (nm / 1000 rpm), the formula (A1), formula (B1), formula (B2), formula (C1) And formulas to satisfy the (C2).
Formula (A1): 0.01 <Rmf <0.20
Formula (B1): 0.005 <Rmf / Wh <5.000
Formula (B2): 0.002 <Rmf / Wl <1.000
Formula (C1): 1.0 <Whmax / Whmin <2.5
Formula (C2): 1.0 <Wlmax / Wlmin <2.5

Here, “when an image including three types of image patterns having different image densities is repeatedly formed in a high temperature and high humidity environment or a low temperature and low humidity environment” means “a high temperature and high humidity environment (temperature 29 ° C., humidity 85% RH environment). ) Or in a low-temperature and low-humidity environment (temperature of 10 ° C. and humidity of 15% RH), as shown in FIG. 6, 4 dots arranged along the paper lateral feed direction (short direction) on A4 paper as a recording medium Three thin line images with a width of 2 mm drawn along the longitudinal direction of the paper and an image density of 100 mm of 18 mm × 9 mm square with a line and a 4-dot space repeated thin line image having a width of 2 mm (the image density of only this part is 50%) 6% solid image 100B, 18mm x 9mm square, 4 dot line and 4 dot space repeated thin line image arranged along the paper longitudinal direction (image density of this part is 50%) The output for forming an image composed of six 100Cs is carried out by carrying 70,000 sheets by conveying the A4 paper in the lateral feed direction (short direction) ”.
Here, three solid images 100B and three thin line images 100C are alternately arranged at equal intervals between three thin line images 100A each having a width of 2 mm drawn along the longitudinal direction of the paper. Form an image.
That is, on the A4 paper as the recording medium, the first image pattern 101A having an image density of 1.4% having only the fine line image 100A and the second image having an image density of 10% having the fine line image 100A and the solid image 100B. An image composed of the pattern 101B and the third image pattern 101C having an image density of 5.7% having the fine line image 100A and the fine line image 100C is formed.
The image density of each image pattern is an average value of image density in the paper feed direction (in this embodiment, the lateral feed direction (short direction)), and is a repetitive thin line image of 4 dot lines and 4 dot spaces. The portion of the first image pattern having only the 2 mm thin line image 100A is 2 mm × 3 portions (2 × 3 × 50%) / 210 = 1.4% where the image density is 50% with respect to the paper width of 210 mm. Similarly, the portion of the second image pattern 101B having the fine line image 100A and the solid image 100B is {(2 × 3 × 50%) + (9 × 2 × 100%)} / 210 = 10%, The portion of the third image pattern 101C having the image density of 5.7% having the image 100A and the fine line image 100C is {(2 × 3 × 50%) + (9 × 2 × 50%)} / 210 = 5.7% The concentration is defined as

The average wear rate of the photoconductor, the maximum wear rate of the photoconductor, and the minimum wear rate of the photoconductor in each environment are values measured by the following methods.
Using an optical film thickness measuring device (line interference film thickness meter), measure the film thickness profile of the outermost surface layer along the longitudinal direction of the photoconductor in the area corresponding to the image forming area excluding both ends in the axial direction of the photoconductor. To do. The film thickness profile of the outermost surface layer was an average measured at four locations at equal intervals in the circumferential direction of the photoreceptor (four locations of 0 °, 90 °, 180 °, and 270 ° when viewed from the cross section of the photoreceptor). Create as a value. Then, under each environment, the film thickness profile of the outermost surface layer is created before and after the output for forming an image, and the average wear rate of the photoreceptor is based on the difference in the film thickness profile of the outermost surface layer before and after the output. The maximum wear rate of the photoconductor and the minimum wear rate of the photoconductor are calculated.
Each wear rate is calculated in terms of a wear rate per 1,000 rotations (cycles) of the photoreceptor. That is, each wear rate is a wear rate per 1,000 rotations (cycles) of the photoreceptor.

  In the image forming method (apparatus) according to the present embodiment, a high-temperature and high-humidity environment (temperature 29 ° C., humidity 85% RH) or a low-temperature low-humidity environment (temperature 10 ° C., humidity 15% RH) has the above configuration. ), Even when an image having a low image density (image density of 1.4%) or a high image density (image density of 10%) is repeatedly formed, an image in which density unevenness is suppressed over a long period of time can be obtained. The reason for this is not clear, but is presumed to be as follows.

  2. Description of the Related Art Conventionally, a technique for suppressing wear on the outermost surface layer of a photoreceptor using a toner containing fatty acid metal salt particles is known. However, when a curable photoconductor having an outermost surface layer is applied with a cured film of a composition containing a reactive charge transport material, the mechanical strength of the outermost surface layer is high. In any environment, abrasion of the outermost surface layer may be excessively suppressed. If the abrasion of the outermost layer is excessively suppressed, the fatty acid metal salt tends to be excessively deposited on the surface of the photoreceptor. In particular, when the contact type or proximity type charging method is adopted, the influence of the discharge is strong, and the lubricity is lowered due to the deterioration of the deposited fatty acid metal salt, and the discharge product is likely to remain.

  For this reason, when images are repeatedly formed, a mechanical load is applied to the cleaning blade, chipping or abrasion occurs, leading to poor cleaning, and image density unevenness is likely to occur. This phenomenon is likely to occur when an image including a solid image having a high image density is repeatedly formed. This is because a solid image is an image with a large amount of toner, and the amount of fatty acid metal salt particles supplied to the surface of the photoreceptor also increases, which may cause partial cleaning failure and easily cause density unevenness. That is, it is considered that the amount of toner supplied to the surface of the photoreceptor (that is, the amount of fatty acid metal salt particles) is changed depending on the level of image density, thereby causing unevenness in density unevenness.

  As described above, in an image forming method (apparatus) in which a toner containing fatty acid metal salt particles and a curable photoconductor are applied, charged by a contact or proximity charging method, and cleaned by a cleaning blade method, a high temperature and high humidity environment Or, even when an image having a low image density or a high image density is repeatedly formed in a low-temperature and low-humidity environment, the content of the fatty acid metal salt particles in the toner (that is, the surface of the photoreceptor) It has been found that the outermost surface layer of the photoreceptor needs to be appropriately worn according to the amount of fatty acid metal salt particles supplied to the toner.

  Therefore, in the image forming method according to the present embodiment, the expressions (A1), (B1), (B2), (C1), and (C2) are satisfied. That is, the content of the fatty acid metal salt particles is controlled so as to satisfy the formula (A1), and the amount of the fatty acid metal salt supplied to the surface of the curable photoreceptor is limited. In addition, the content of fatty acid metal salt particles in the toner so as to satisfy the formulas (B1) and (B2) when images including three types of image patterns having different image densities are repeatedly formed in each environment. That is, the ratio of the amount of fatty acid metal salt particles supplied to the surface of the photoconductor and the average wear rate of the photoconductor is controlled so that the outermost surface layer of the photoconductor is appropriately worn. In addition, the ratio between the maximum wear rate and the minimum wear rate of the photoconductor is controlled so as to satisfy the expressions (C1) and (C2), and the difference between the maximum wear rate and the minimum wear rate of the photoconductor is controlled. Suppress.

  Further, a cured film of a composition containing two or more kinds of reactive charge transport materials, or a cured film of a composition containing a reactive charge transport material and a reactive material having no charge transport skeleton, By constituting the layer, the affinity of the outermost surface layer for the fatty acid metal salt is lowered, and the adhesion or adsorption property of the fatty acid metal salt is reduced. When the adhesion or adsorption property of the fatty acid metal salt is reduced, the peelability of the fatty acid metal salt from the outermost surface layer is increased, and the fatty acid metal salt is prevented from being excessively deposited on the outermost surface layer.

  In this way, protection, wear (refresh), and lubricity are appropriately controlled in the outermost surface layer of the curable photoreceptor. Thereby, along with the adhesion of the discharge product to the surface of the curable photoconductor, the cleaning failure due to wear or chipping of the cleaning blade can be suppressed over a long period of time.

For this reason, in the image forming method (apparatus) according to the present embodiment, even when an image having a low image density or a high image density is repeatedly formed in a high-temperature and high-humidity environment or a low-temperature and low-humidity environment, density unevenness is suppressed over a long period of time. The obtained image is obtained.
Further, in the image forming method (apparatus) according to the present embodiment, since the discharge product adheres to the surface of the photoconductor and the cleaning failure due to wear or chipping of the cleaning blade is suppressed, the image flow is also long-term. It becomes easy to be suppressed.

  In addition, in a color image forming method (apparatus) that is a combination of an image forming process (image forming unit) of a cyan image, a magenta image, a yellow image, and a black image that are commonly used, about an image output in the market. 20% to 30% are color images. That is, in the market, image formation using an image forming process (image forming unit) of a cyan image, a magenta image, a yellow image, and a black image is only about 20% to 30% of the total output. On the other hand, in the market, an image forming process (image forming unit) of a black image is used for almost all outputs, so that density unevenness of an image tends to occur and the life is shortest. This is the same because a monochrome image forming method (apparatus) that uses only an image forming process (image forming unit) of a black image is also used most in the market.

As described above, the image forming method (apparatus) according to the present embodiment is preferably applied to an image forming process (image forming unit) of a black image that is most utilized in the market.
Specifically, in the image forming method according to the present embodiment, the electrostatic latent image formed on the surface of the photoreceptor is developed with a developer containing black (black) toner to form a black (black) toner image. It is preferable to have a developing step. In addition, the image forming apparatus according to the present embodiment accommodates a developer containing black toner, and develops the electrostatic latent image formed on the surface of the photosensitive member with the developer to develop black (black) toner. It is preferable to provide developing means for forming an image.

Here, although the image forming method (apparatus) according to the present embodiment satisfies the formula (A1), it is preferable to satisfy the following formula (A1-2) from the viewpoint of suppressing the density unevenness of the image. -3) is more preferably satisfied.
Moreover, although satisfy | filling Formula (B1), it is preferable to satisfy | fill following Formula (B1-2) from the point of the density unevenness suppression of an image, and it is still more preferable to satisfy | fill following Formula (B1-3).
Moreover, although satisfy | filling Formula (B2), it is preferable to satisfy | fill following Formula (B2-2) from the point of the density unevenness suppression of an image, and it is still more preferable to satisfy | fill following Formula (B2-3).
Moreover, although satisfy | filling Formula (C1), it is preferable to satisfy | fill following formula (C1-2) from the point of the density unevenness suppression of an image, and it is still more preferable to satisfy | fill following formula (C1-3).
Moreover, although satisfy | filling Formula (C2), it is preferable to satisfy | fill following Formula (C2-2) from the point of the density unevenness suppression of an image, and it is still more preferable to satisfy | fill following Formula (C2-3).

Formula (A1): 0.01 <Rmf <0.20
Formula (A1-2): 0.015 <Rmf <0.19
Formula (A1-3): 0.02 <Rmf <0.18

Formula (B1): 0.005 <Rmf / Wh <5.000
Formula (B1-2): 0.005 <Rmf / Wh <4.950
Formula (B1-3): 0.005 <Rmf / Wh <4.900

Formula (B2): 0.002 <Rmf / Wl <1.000
Formula (B2-2): 0.002 <Rmf / Wl <0.950
Formula (B2-3): 0.002 <Rmf / Wl <0.900

Formula (C1): 1.0 <Whmax / Whmin <2.5
Formula (C1-2): 1.050 <Whmax / Whmin <2.450
Formula (C1-3): 1.100 <Whmax / Whmin <2.400

Formula (C2): 1.0 <Wlmax / Wlmin <2.5
Formula (C2-2): 1.050 <Wlmax / Wlmin <2.450
Formula (C2-3): 1.100 <Wlmax / Wlmin <2.400

  In the image forming method (apparatus) according to the present invention, the fatty acid metal salt particles satisfy the formula (B1), the formula (B2), the formula (C1), and the formula (C2), and suppress density unevenness of the image. Zinc stearate particles having a volume-based median diameter of 0.1 μm to 10.0 μm are preferable. When this particle is applied as a fatty acid metal salt particle, the specific surface area of the particle is large, the contact with the surface of the photoreceptor is improved, and the coverage of the fatty acid metal salt on the surface of the photoreceptor is excessively reduced. suppress. For this reason, the photoconductor is easily abraded moderately, and the fatty acid metal salt hardly remains on the surface of the photoconductor. As a result, it is easy to satisfy each of the above expressions, and uneven density of the image is easily suppressed.

In the image forming method (apparatus) according to the present invention, the reactive charge transport material satisfies the formula (B1), the formula (B2), the formula (C1), and the formula (C2) and suppresses the density unevenness of the image. The chain polymerizable compound preferably has at least a charge transporting skeleton and a chain polymerizable functional group in the same molecule.
In particular, from the viewpoints of electrical characteristics and mechanical strength, the chain polymerizable compound is represented by the general formula (I) or (II) (hereinafter referred to as “specific chain polymerizable charge transport material”). May also be selected. The reason for this is not clear, but is thought to be as follows.

A cured film of a composition containing two or more kinds of specific chain polymerizable charge transport materials (a film containing a polymer or a cross-linked product (particularly cross-linked product) of two or more specific chain polymerizable charge transport materials), or A cured film of a composition comprising a specific chain polymerizable charge transport material and a reactive material having no charge transport skeleton (a specific chain polymerizable charge transport material and a reactive material having no charge transport skeleton) When the polymer or crosslinked product (particularly a film containing a crosslinked product) is used as the outermost surface layer, the outermost surface layer has excellent electrical properties and mechanical strength. Moreover, thickening of the outermost surface layer (for example, 10 μm or more) is also realized. This is because the specific chain polymerizable charge transport material itself has excellent charge transport performance, and there are few polar groups that hinder carrier transport such as —OH and —NH—, and vinyl phenyl having π electrons effective for carrier transport. This is probably because the material is linked by polymerization with a group (styryl group), so that residual strain is suppressed and formation of a structural trap for trapping charges is suppressed.
In addition, since a specific chain polymerizable charge transport material has a property of being more hydrophobic and less susceptible to moisture than an acrylic material, it is considered that electric characteristics are easily maintained over a long period of time.
Furthermore, the specific chain polymerizable charge transport material has higher hydrophobicity than the acrylic material, and has higher affinity with the fatty acid metal salt (particularly zinc stearate). For this reason, it is considered that a small amount of fatty acid metal salt (particularly zinc stearate) is likely to be coated on the surface of the protective layer (outermost surface layer).
For this reason, a cured film of a composition containing two or more kinds of specific chain polymerizable charge transport materials (a film containing a polymer or a crosslinked product (particularly, a crosslinked product) of two or more specific chain polymerizable charge transport materials) Or a cured film of a composition comprising a specific chain polymerizable charge transport material and a reactive material not having a charge transport skeleton (reaction not having a specific chain polymerizable charge transport material and a charge transport skeleton) If the outermost surface layer has a polymer or a crosslinked material (particularly a film containing a crosslinked body) with a functional material, the electrical characteristics and mechanical strength of the outermost surface layer are likely to increase.

On the other hand, a specific chain-polymerizable charge transport material has a styryl group, and this styryl group has high affinity with a general non-reactive charge transport material having no reactive group. That is, it is easy to increase the amount of the non-reactive charge transport material included in the outermost surface layer. For this reason, adjustment of the mechanical strength of the outermost surface layer (for example, reduction in mechanical strength) is easily realized by the amount of the non-reactive charge transport material to be included.
In particular, among specific chain polymerizable charge transport materials, a material having an ether bond (—O—) as a linking group between a charge transport skeleton and a chain polymerizable functional group (for example, L in the general formula (I)) A material in which the group shown has an ether bond (—O—), a material in which the group represented by L ′ in the general formula (II) has an ether bond (—O—), the general formula (IIA-a3) or (IIA— The material having a4), etc. has a low polarity, so has a high charge transporting property and a high affinity with a non-reactive charge transporting material, and adjustment of the mechanical strength of the outermost surface layer (for example, mechanical strength) (Intentional reduction) is easy to achieve.

  Therefore, when a specific chain-polymerizable charge transport material is applied as the reactive charge transport material, it is effective in controlling the wear rate of the photoreceptor and suppressing the density unevenness of the image so as to satisfy the above formulas. .

In the image forming method (apparatus) according to the present invention, the outermost surface layer satisfies the formula (B1), the formula (B2), the formula (C1), and the formula (C2) and suppresses the density unevenness of the image. It is preferable that it is comprised with the cured film of the composition containing a reactive charge transport material and the reactive material which does not have a charge transportable frame | skeleton.
In addition, the reactive material has a charge transporting skeleton in the same molecule from the viewpoint of satisfying the formula (B1), the formula (B2), the formula (C1), and the formula (C2) and suppressing the density unevenness of the image. The chain-polymerizable compound having at least a chain-polymerizable functional group (hereinafter also referred to as “specific chain-polymerizable material”) is preferable.
A cured film (reactive charge transport material (especially a specific chain polymerizable charge transport material)) and a specific composition comprising a reactive charge transport material (especially a specific chain polymerizable charge transport material) and a specific chain polymerizable material By forming the outermost surface layer with a polymer or a crosslinked body (particularly a film containing a crosslinked body) with the chain polymerizable material, the affinity of the outermost surface layer to the fatty acid metal salt tends to be low, and the fatty acid metal It becomes easy to reduce the adhesion or adsorption of the salt. For this reason, the peelability of the fatty acid metal salt from the outermost surface layer is further easily increased, and the fatty acid metal salt is easily prevented from being excessively deposited on the outermost surface layer. As a result, even when an image having a low image density or a high image density is repeatedly formed in a high-temperature and high-humidity environment or a low-temperature and low-humidity environment, an image in which density unevenness is suppressed over a long period of time can be easily obtained.

  In the image forming method (apparatus) according to the present invention, the volume average particle size of the toner particles of the developer may be 3.0 μm or more and 3.7 μm or less. Even when a low image density or a high image density image is repeatedly formed by applying a developer containing small toner particles having a volume average particle size of 3.0 μm or more and 3.7 μm or less, density unevenness over a long period of time. It is easy to obtain an image in which the above is suppressed.

  In the image forming method (apparatus) according to the present embodiment, examples of a method for adjusting the average wear rate, the maximum wear rate, and the minimum wear rate of the photoconductor include, for example, mechanical of the outermost surface layer of the curable photoconductor. Strength, 2) A method of controlling the type, particle size or content of fatty acid metal salt particles in the toner.

The image forming method according to the present embodiment includes a fixing step of fixing a toner image transferred to the surface of a recording medium; direct transfer for directly transferring a toner image formed on the surface of an electrophotographic photosensitive member to a recording medium Method: Intermediate transfer in which the toner image formed on the surface of the electrophotographic photoreceptor is primarily transferred to the surface of the intermediate transfer member, and the toner image transferred to the surface of the intermediate transfer member is secondarily transferred to the surface of the recording medium. A method having a charge eliminating step of irradiating the surface of the image holding member with a charge removing light after the toner image is transferred and before charging; a step of increasing the temperature of the electrophotographic photosensitive member and reducing the relative temperature. A known image forming method such as a method having the same is applied.
In the case of the intermediate transfer method, the transfer method includes, for example, a primary transfer method in which a toner image formed on the surface of the image carrier is primarily transferred onto the surface of the intermediate transfer member, and a toner transferred on the surface of the intermediate transfer member. And a secondary transfer method for secondary transfer of the image onto the surface of the recording medium.

On the other hand, the image forming apparatus according to the present embodiment includes a fixing unit that fixes the toner image transferred to the surface of the recording medium; directly transfers the toner image formed on the surface of the electrophotographic photosensitive member to the recording medium. Direct transfer type apparatus; primary transfer of the toner image formed on the surface of the electrophotographic photosensitive member to the surface of the intermediate transfer member, and secondary transfer of the toner image transferred to the surface of the intermediate transfer member to the surface of the recording medium Intermediate transfer system device; Device that includes a charge eliminating means that discharges the surface of the image carrier after the toner image is transferred and before charging. The temperature of the electrophotographic photosensitive member is increased to reduce the relative temperature. A known image forming apparatus such as an apparatus provided with an electrophotographic photosensitive member heating member is applied.
In the case of an intermediate transfer type apparatus, the transfer means includes, for example, an intermediate transfer body on which a toner image is transferred to the surface and a primary transfer that primarily transfers the toner image formed on the surface of the image holding body to the surface of the intermediate transfer body And a secondary transfer unit that secondarily transfers the toner image transferred onto the surface of the intermediate transfer member onto the surface of the recording medium.

  The image forming method (apparatus) according to this embodiment may be either a dry developing image forming method (apparatus) or a wet developing (developing method using a liquid developer) image forming method (apparatus). Good.

  Note that in the image forming apparatus according to the present embodiment, for example, the portion including the electrophotographic photosensitive member may have a cartridge structure (process cartridge) that is detachable from the image forming apparatus. As the process cartridge, for example, a process cartridge including an electrophotographic photosensitive member, a developing unit, and a cleaning unit is preferably used. In addition to the electrophotographic photosensitive member, the process cartridge may include at least one selected from the group consisting of a charging unit, an electrostatic latent image forming unit, and a transfer unit.

  Hereinafter, an example of the image forming apparatus according to the present embodiment will be described, but the present invention is not limited thereto. In addition, the main part shown to a figure is demonstrated and the description is abbreviate | omitted about others.

FIG. 4 is a schematic configuration diagram illustrating an example of an image forming apparatus according to the present embodiment.
As shown in FIG. 4, the image forming apparatus 100 according to the present embodiment includes a process cartridge 300 including an electrophotographic photosensitive member 7, an exposure device 9 (an example of an electrostatic latent image forming unit), and a transfer device 40 (primary. Transfer device) and an intermediate transfer member 50. In the image forming apparatus 100, the exposure device 9 is disposed at a position where the electrophotographic photosensitive member 7 can be exposed from the opening of the process cartridge 300, and the transfer device 40 is interposed between the electrophotographic photosensitive member via the intermediate transfer member 50. 7, and a part of the intermediate transfer member 50 is disposed in contact with the electrophotographic photosensitive member 7. Although not shown, it also has a secondary transfer device that transfers the toner image transferred to the intermediate transfer member 50 to a recording medium (for example, paper). The intermediate transfer member 50, the transfer device 40 (primary transfer device), and the secondary transfer device (not shown) correspond to an example of a transfer unit.

  In the process cartridge 300 in FIG. 4, an electrophotographic photosensitive member 7, a charging device 8 (an example of a charging unit), a developing device 11 (an example of a developing unit), and a cleaning device 13 (an example of a cleaning unit) are integrated in a housing. I support it. The cleaning device 13 includes a cleaning blade (an example of a cleaning member) 131, and the cleaning blade 131 is disposed so as to contact the surface of the electrophotographic photosensitive member 7.

  In FIG. 4, as an image forming apparatus, a fibrous member 132 (roll shape) for supplying the lubricant 14 to the surface of the electrophotographic photosensitive member 7 and a fibrous member 133 (flat brush shape) for assisting cleaning are shown. Examples are provided, but these are arranged as necessary.

  Hereinafter, each configuration of the image forming apparatus according to the present embodiment will be described.

(Electrophotographic photoreceptor)
The electrophotographic photosensitive member has a conductive substrate and a photosensitive layer provided on the conductive substrate. The outermost surface layer of the photoreceptor is composed of a cured film of a composition containing a reactive charge transport material.

In the electrophotographic photosensitive member, the outermost surface layer only needs to form the uppermost surface of the electrophotographic photosensitive member itself, and is provided as a layer that functions as a protective layer or a layer that functions as a charge transport layer. When the outermost surface layer is a layer functioning as a protective layer, a photosensitive layer composed of a charge transport layer and a charge generation layer or a single-layer type photosensitive layer is provided under the protective layer.
Specifically, in the case where the outermost surface layer functions as a protective layer, a photosensitive layer (a charge generation layer and a charge transport layer or a single-layer type photosensitive layer) is formed on the conductive substrate, and a protective layer is formed as the outermost surface layer. Are formed sequentially. On the other hand, in the case where the outermost surface layer functions as a charge transport layer, an embodiment in which a charge generation layer and a charge transport layer as the outermost surface layer are sequentially formed on a conductive substrate can be mentioned.

  Hereinafter, the electrophotographic photoreceptor according to the exemplary embodiment in the case where the outermost surface layer functions as a protective layer will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic cross-sectional view showing an example of the electrophotographic photosensitive member according to the present embodiment. 2 to 3 are schematic sectional views showing other examples of the electrophotographic photosensitive member according to this embodiment.

  An electrophotographic photoreceptor 7A shown in FIG. 1 is a so-called function-separated photoreceptor (or laminated photoreceptor), and an undercoat layer 1 is provided on a conductive substrate 4, on which a charge generation layer 2 and a charge are formed. The transport layer 3 and the protective layer 5 have a structure formed sequentially. In the electrophotographic photoreceptor 7A, the charge generation layer 2 and the charge transport layer 3 constitute a photosensitive layer.

An electrophotographic photoreceptor 7B shown in FIG. 2 is a function-separated type photoreceptor in which the functions are separated into the charge generation layer 2 and the charge transport layer 3 like the electrophotographic photoreceptor 7A shown in FIG.
In the electrophotographic photoreceptor 7B shown in FIG. 2, a structure in which an undercoat layer 1 is provided on a conductive substrate 4, and a charge transport layer 3, a charge generation layer 2, and a protective layer 5 are sequentially formed thereon. It is what has. In the electrophotographic photoreceptor 7B, the charge transport layer 3 and the charge generation layer 2 constitute a photosensitive layer.

  The electrophotographic photoreceptor 7C shown in FIG. 3 contains a charge generation material and a charge transport material in the same layer (single layer type photosensitive layer 6). The electrophotographic photoreceptor 7C shown in FIG. 3 has a structure in which an undercoat layer 1 is provided on a conductive substrate 4, and a single-layer type photosensitive layer 6 and a protective layer 5 are sequentially formed thereon. .

In the electrophotographic photoreceptors 7A, 7B and 7C shown in FIGS. 1, 2 and 3, the protective layer 5 is the outermost surface layer disposed on the side farthest from the conductive substrate 4, and The surface layer has the above-described configuration.
In the electrophotographic photosensitive member shown in FIGS. 1, 2, and 3, the undercoat layer 1 may or may not be provided.

  Hereinafter, each element will be described based on the electrophotographic photosensitive member 7A shown in FIG. 1 as a representative example. Note that the reference numerals are omitted.

(Conductive substrate)
Examples of the conductive substrate include metal plates (eg, aluminum, copper, zinc, chromium, nickel, molybdenum, vanadium, indium, gold, platinum, etc.) or alloys (stainless steel, etc.), metal drums, metal belts, etc. Is mentioned. In addition, as the conductive substrate, for example, paper, resin film, belt, etc. coated, vapor-deposited or laminated with a conductive compound (for example, conductive polymer, indium oxide, etc.), metal (for example, aluminum, palladium, gold, etc.) or an alloy, etc. Also mentioned. Here, “conductive” means that the volume resistivity is less than 10 ¹³ Ωcm.

  When the electrophotographic photosensitive member is used in a laser printer, the surface of the conductive substrate has a center line average roughness Ra of 0.04 μm or more and 0.5 μm for the purpose of suppressing interference fringes generated when laser light is irradiated. The surface is preferably roughened below. When non-interfering light is used as a light source, roughening for preventing interference fringes is not particularly required, but it is suitable for extending the life because it suppresses generation of defects due to irregularities on the surface of the conductive substrate.

  Examples of roughening methods include wet honing by suspending an abrasive in water and spraying the conductive substrate, centerless grinding in which the conductive substrate is pressed against a rotating grindstone, and grinding is performed continuously. And anodizing treatment.

  As a roughening method, without roughening the surface of the conductive substrate, conductive or semiconductive powder is dispersed in the resin to form a layer on the surface of the conductive substrate. A method of roughening with particles dispersed in the layer may also be mentioned.

  In the roughening treatment by anodic oxidation, a metal (for example, aluminum) conductive substrate is used as an anode, and an oxide film is formed on the surface of the conductive substrate by anodizing in an electrolyte solution. Examples of the electrolyte solution include a sulfuric acid solution and an oxalic acid solution. However, the porous anodic oxide film formed by anodic oxidation is chemically active as it is, easily contaminated, and has a large resistance fluctuation due to the environment. Therefore, the pores of the oxide film are blocked by the volume expansion due to the hydration reaction in pressurized water vapor or boiling water (a metal salt such as nickel may be added) against the porous anodic oxide film, and more stable hydration oxidation It is preferable to perform a sealing treatment for changing to a product.

  The thickness of the anodized film is preferably, for example, 0.3 μm or more and 15 μm or less. When this film thickness is within the above range, the barrier property against implantation tends to be exhibited, and the increase in residual potential due to repeated use tends to be suppressed.

The conductive substrate may be treated with an acidic treatment liquid or boehmite treatment.
The treatment with the acidic treatment liquid is performed as follows, for example. First, an acidic treatment liquid containing phosphoric acid, chromic acid and hydrofluoric acid is prepared. The mixing ratio of phosphoric acid, chromic acid and hydrofluoric acid in the acidic treatment liquid is, for example, in the range of 10% by mass to 11% by mass of phosphoric acid, in the range of 3% by mass to 5% by mass of chromic acid, The concentration of these acids is preferably in the range of 13.5% by mass or more and 18% by mass or less. The treatment temperature is preferably 42 ° C. or higher and 48 ° C. or lower, for example. The film thickness is preferably from 0.3 μm to 15 μm.

  The boehmite treatment is performed, for example, by immersing in pure water of 90 ° C. or higher and 100 ° C. or lower for 5 minutes to 60 minutes, or by contacting with heated steam of 90 ° C. or higher and 120 ° C. or lower for 5 minutes to 60 minutes. The film thickness is preferably 0.1 μm or more and 5 μm or less. This may be further anodized using an electrolyte solution with low film solubility such as adipic acid, boric acid, borate, phosphate, phthalate, maleate, benzoate, tartrate, citrate, etc. Good.

(Undercoat layer)
The undercoat layer is, for example, a layer containing inorganic particles and a binder resin.

Examples of the inorganic particles include inorganic particles having a powder resistance (volume resistivity) of 10 ² Ωcm or more and 10 ¹¹ Ωcm or less.
Among these, as the inorganic particles having the resistance value, for example, metal oxide particles such as tin oxide particles, titanium oxide particles, zinc oxide particles, and zirconium oxide particles are preferable, and zinc oxide particles are particularly preferable.

The specific surface area of the inorganic particles by the BET method is preferably 10 m ² / g or more, for example.
The volume average particle diameter of the inorganic particles is, for example, preferably from 50 nm to 2000 nm (preferably from 60 nm to 1000 nm).

  For example, the content of the inorganic particles is preferably 10% by mass or more and 80% by mass or less, and more preferably 40% by mass or more and 80% by mass or less with respect to the binder resin.

  The inorganic particles may be subjected to a surface treatment. Two or more inorganic particles having different surface treatments or particles having different particle diameters may be mixed and used.

  Examples of the surface treatment agent include a silane coupling agent, a titanate coupling agent, an aluminum coupling agent, and a surfactant. In particular, a silane coupling agent is preferable, and an amino group-containing silane coupling agent is more preferable.

  Examples of the silane coupling agent having an amino group include 3-aminopropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, and N-2- (aminoethyl) -3-amino. Examples include, but are not limited to, propylmethyldimethoxysilane, N, N-bis (2-hydroxyethyl) -3-aminopropyltriethoxysilane, and the like.

  Two or more silane coupling agents may be used in combination. For example, a silane coupling agent having an amino group and another silane coupling agent may be used in combination. Other silane coupling agents include, for example, vinyltrimethoxysilane, 3-methacryloxypropyl-tris (2-methoxyethoxy) silane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycol. Sidoxypropyltrimethoxysilane, vinyltriacetoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- ( Aminoethyl) -3-aminopropylmethyldimethoxysilane, N, N-bis (2-hydroxyethyl) -3-aminopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, and the like, but are not limited thereto. It is not a thing.

  The surface treatment method using the surface treatment agent may be any method as long as it is a known method, and may be either a dry method or a wet method.

  The treatment amount of the surface treatment agent is preferably 0.5% by mass or more and 10% by mass or less with respect to the inorganic particles, for example.

  Here, the undercoat layer may contain an electron-accepting compound (acceptor compound) together with the inorganic particles from the viewpoint of enhancing the long-term stability of the electric characteristics and the carrier blocking property.

Examples of the electron accepting compound include quinone compounds such as chloranil and bromoanil; tetracyanoquinodimethane compounds; 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitro-9-fluorenone, and the like. 2- (4-biphenyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole, 2,5-bis (4-naphthyl) -1,3,4- Oxadiazole compounds such as oxadiazole and 2,5-bis (4-diethylaminophenyl) -1,3,4 oxadiazole; xanthone compounds; thiophene compounds; 3,3 ′, 5,5 ′ tetra- electron transporting substances such as diphenoquinone compounds such as t-butyldiphenoquinone;
In particular, the electron-accepting compound is preferably a compound having an anthraquinone structure. As the compound having an anthraquinone structure, for example, a hydroxyanthraquinone compound, an aminoanthraquinone compound, an aminohydroxyanthraquinone compound, and the like are preferable, and specifically, for example, anthraquinone, alizarin, quinizarin, anthralfin, and purpurin are preferable.

  The electron-accepting compound may be dispersed and included in the undercoat layer together with the inorganic particles, or may be included in a state of being attached to the surface of the inorganic particles.

  Examples of the method for attaching the electron accepting compound to the surface of the inorganic particles include a dry method or a wet method.

  In the dry method, for example, while stirring inorganic particles with a mixer having a large shearing force or the like, an electron-accepting compound dissolved directly or in an organic solvent is dropped and sprayed with dry air or nitrogen gas. It is a method of adhering to the surface of inorganic particles. When the electron-accepting compound is dropped or sprayed, it is preferably performed at a temperature not higher than the boiling point of the solvent. After dropping or spraying the electron-accepting compound, baking may be performed at 100 ° C. or higher. The baking is not particularly limited as long as it is a temperature and time for obtaining electrophotographic characteristics.

  In the wet method, for example, an electron-accepting compound is added while dispersing inorganic particles in a solvent by stirring, ultrasonic waves, a sand mill, an attritor, a ball mill, etc., and after stirring or dispersing, the solvent is removed to remove electrons. This is a method of attaching a receptive compound to the surface of inorganic particles. The solvent removal method is distilled off by filtration or distillation, for example. After removing the solvent, baking may be performed at 100 ° C. or higher. The baking is not particularly limited as long as it is a temperature and time for obtaining electrophotographic characteristics. In the wet method, the water content of the inorganic particles may be removed before adding the electron-accepting compound. Examples thereof include a method of removing while stirring and heating in a solvent, and a method of removing by azeotropic distillation with a solvent. Can be mentioned.

  The attachment of the electron-accepting compound may be performed before or after the surface treatment with the surface treatment agent is performed on the inorganic particles, or may be performed simultaneously with the attachment of the electron-accepting compound and the surface treatment with the surface treatment agent.

  The content of the electron-accepting compound is, for example, from 0.01% by mass to 20% by mass with respect to the inorganic particles, and preferably from 0.01% by mass to 10% by mass.

Examples of the binder resin used for the undercoat layer include acetal resins (eg, polyvinyl butyral), polyvinyl alcohol resins, polyvinyl acetal resins, casein resins, polyamide resins, cellulose resins, gelatin, polyurethane resins, polyester resins, and unsaturated polyesters. Resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone-alkyd resin, urea resin, phenol resin, phenol-formaldehyde resin, melamine resin, Known polymer compounds such as urethane resin, alkyd resin, epoxy resin; zirconium chelate compound; titanium chelate compound; aluminum chelate compound; titanium alkoxide compound ; Organic titanium compounds; known materials silane coupling agent, and the like.
Examples of the binder resin used for the undercoat layer include a charge transport resin having a charge transport group, a conductive resin (for example, polyaniline) and the like.

Among these, as the binder resin used for the undercoat layer, a resin insoluble in the upper coating solvent is preferable, and in particular, a urea resin, a phenol resin, a phenol-formaldehyde resin, a melamine resin, a urethane resin, and an unsaturated polyester. Thermosetting resins such as resins, alkyd resins, and epoxy resins; at least one resin selected from the group consisting of polyamide resins, polyester resins, polyether resins, methacrylic resins, acrylic resins, polyvinyl alcohol resins, and polyvinyl acetal resins; Resins obtained by reaction with curing agents are preferred.
When these binder resins are used in combination of two or more, the mixing ratio is set as necessary.

The undercoat layer may contain various additives for improving electrical characteristics, improving environmental stability, and improving image quality.
Additives include known materials such as electron transport pigments such as polycyclic condensation systems and azo systems, zirconium chelate compounds, titanium chelate compounds, aluminum chelate compounds, titanium alkoxide compounds, organic titanium compounds, and silane coupling agents. It is done. The silane coupling agent is used for the surface treatment of the inorganic particles as described above, but may be further added to the undercoat layer as an additive.

  Examples of the silane coupling agent as the additive include vinyltrimethoxysilane, 3-methacryloxypropyl-tris (2-methoxyethoxy) silane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3- Glycidoxypropyltrimethoxysilane, vinyltriacetoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (Aminoethyl) -3-aminopropylmethylmethoxysilane, N, N-bis (2-hydroxyethyl) -3-aminopropyltriethoxysilane, 3-chloropropyltrimethoxysilane and the like can be mentioned.

  Examples of the zirconium chelate compound include zirconium butoxide, zirconium zirconium acetoacetate, zirconium triethanolamine, acetylacetonate zirconium butoxide, ethyl acetoacetate butoxide, zirconium acetate, zirconium oxalate, zirconium lactate, zirconium phosphonate, zirconium octoate, Zirconium naphthenate, zirconium laurate, zirconium stearate, zirconium isostearate, methacrylate zirconium butoxide, stearate zirconium butoxide, isostearate zirconium butoxide and the like.

  Examples of titanium chelate compounds include tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate ammonium salt. , Titanium lactate, titanium lactate ethyl ester, titanium triethanolamate, polyhydroxy titanium stearate and the like.

  Examples of the aluminum chelate compound include aluminum isopropylate, monobutoxy aluminum diisopropylate, aluminum butyrate, diethyl acetoacetate aluminum diisopropylate, aluminum tris (ethyl acetoacetate) and the like.

  These additives may be used alone or as a mixture or polycondensate of a plurality of compounds.

The undercoat layer preferably has a Vickers hardness of 35 or more.
The surface roughness (ten-point average roughness) of the undercoat layer is adjusted from 1 / 4n (n is the refractive index of the upper layer) to 1 / 2λ of the exposure laser wavelength λ used to suppress moire images. It should be done.
Resin particles or the like may be added to the undercoat layer for adjusting the surface roughness. Examples of the resin particles include silicone resin particles and cross-linked polymethyl methacrylate resin particles. Further, the surface of the undercoat layer may be polished for adjusting the surface roughness. Examples of the polishing method include buffing, sandblasting, wet honing, and grinding.

  There is no particular limitation on the formation of the undercoat layer, and a well-known formation method is used. For example, a coating film for forming an undercoat layer in which the above components are added to a solvent is formed, and the coating film is dried. And heating as necessary.

Solvents for preparing the coating solution for forming the undercoat layer include known organic solvents such as alcohol solvents, aromatic hydrocarbon solvents, halogenated hydrocarbon solvents, ketone solvents, ketone alcohol solvents, ether solvents. Examples include solvents and ester solvents.
Specific examples of these solvents include methanol, ethanol, n-propanol, iso-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, Examples include ordinary organic solvents such as n-butyl acetate, dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, and toluene.

  Examples of the dispersion method of the inorganic particles when preparing the coating liquid for forming the undercoat layer include known methods such as a roll mill, a ball mill, a vibration ball mill, an attritor, a sand mill, a colloid mill, and a paint shaker.

  Examples of the method for applying the coating liquid for forming the undercoat layer onto the conductive substrate include, for example, a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, and a curtain coating method. The usual methods, such as these, are mentioned.

  The thickness of the undercoat layer is, for example, preferably set in the range of 15 μm or more, more preferably 20 μm or more and 50 μm or less.

(Middle layer)
Although illustration is omitted, an intermediate layer may be further provided between the undercoat layer and the photosensitive layer.
An intermediate | middle layer is a layer containing resin, for example. Examples of the resin used for the intermediate layer include an acetal resin (for example, polyvinyl butyral), polyvinyl alcohol resin, polyvinyl acetal resin, casein resin, polyamide resin, cellulose resin, gelatin, polyurethane resin, polyester resin, methacrylic resin, acrylic resin, Polymer compounds such as polyvinyl chloride resin, polyvinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, melamine resin, and the like can be given.
The intermediate layer may be a layer containing an organometallic compound. Examples of the organometallic compound used for the intermediate layer include organometallic compounds containing metal atoms such as zirconium, titanium, aluminum, manganese, and silicon.
The compounds used for these intermediate layers may be used alone or as a mixture or polycondensate of a plurality of compounds.

  Among these, the intermediate layer is preferably a layer containing an organometallic compound containing a zirconium atom or a silicon atom.

The formation of the intermediate layer is not particularly limited, and a well-known formation method is used. For example, a coating film of an intermediate layer forming coating solution in which the above components are added to a solvent is formed, and the coating film is dried and necessary. It is performed by heating according to.
As the coating method for forming the intermediate layer, usual methods such as a dip coating method, a push-up coating method, a wire bar coating method, a spray coating method, a blade coating method, a knife coating method, and a curtain coating method are used.

  For example, the thickness of the intermediate layer is preferably set in a range of 0.1 μm to 3 μm. An intermediate layer may be used as the undercoat layer.

(Charge generation layer)
The charge generation layer is, for example, a layer containing a charge generation material and a binder resin. The charge generation layer may be a vapor deposition layer of a charge generation material. The vapor-deposited layer of the charge generation material is suitable when an incoherent light source such as an LED (Light Emitting Diode) or an organic EL (Electro-Luminescence) image array is used.

  Examples of the charge generating material include azo pigments such as bisazo and trisazo; fused aromatic pigments such as dibromoanthanthrone; perylene pigments; pyrrolopyrrole pigments; phthalocyanine pigments; zinc oxide;

  Among these, in order to cope with near-infrared laser exposure, it is preferable to use a metal phthalocyanine pigment or a metal-free phthalocyanine pigment as the charge generation material. Specifically, for example, hydroxygallium phthalocyanine disclosed in JP-A-5-263007, JP-A-5-279591, etc .; chlorogallium phthalocyanine disclosed in JP-A-5-98181; More preferred are dichlorotin phthalocyanines disclosed in JP-A No. 140472, JP-A No. 5-140473 and the like; and titanyl phthalocyanine disclosed in JP-A No. 4-189873.

  On the other hand, in order to cope with laser exposure in the near-ultraviolet region, as the charge generation material, condensed aromatic pigments such as dibromoanthanthrone; thioindigo pigments; porphyrazine compounds; zinc oxide; trigonal selenium; Bisazo pigments and the like disclosed in 2004-78147 and JP-A-2005-181992 are preferred.

  The above-described charge generation material may also be used in the case of using an incoherent light source such as an LED having a central wavelength of light emission of 450 nm to 780 nm and an organic EL image array. However, from the viewpoint of resolution, the photosensitive layer is 20 μm or less. When the thin film is used, the electric field strength in the photosensitive layer is increased, and a charge reduction due to charge injection from the base material, so-called image defects called black spots are likely to occur. This becomes conspicuous when a charge generating material that easily generates a dark current is used in a p-type semiconductor such as trigonal selenium or a phthalocyanine pigment.

On the other hand, when an n-type semiconductor such as a condensed ring aromatic pigment, perylene pigment, azo pigment or the like is used as the charge generation material, dark current hardly occurs and even a thin film can suppress image defects called black spots. . Examples of the n-type charge generation material include compounds (CG-1) to (CG-27) described in paragraphs [0288] to [0291] of JP2012-155282A. It is not limited.
The n-type determination is performed by using a time-of-flight method that is usually used, and is determined by the polarity of the flowing photocurrent, and an n-type is more likely to flow electrons as carriers than holes.

The binder resin used for the charge generation layer is selected from a wide range of insulating resins, and the binder resin is selected from organic photoconductive polymers such as poly-N-vinylcarbazole, polyvinyl anthracene, polyvinyl pyrene, and polysilane. You may choose.
As the binder resin, for example, polyvinyl butyral resin, polyarylate resin (polycondensate of bisphenol and aromatic divalent carboxylic acid, etc.), polycarbonate resin, polyester resin, phenoxy resin, vinyl chloride-vinyl acetate copolymer, Examples thereof include polyamide resin, acrylic resin, polyacrylamide resin, polyvinyl pyridine resin, cellulose resin, urethane resin, epoxy resin, casein, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, and the like. Here, “insulating” means that the volume resistivity is 10 ¹³ Ωcm or more.
These binder resins are used singly or in combination of two or more.

  The mixing ratio of the charge generation material and the binder resin is preferably in the range of 10: 1 to 1:10 by mass ratio.

  In addition, the charge generation layer may contain a known additive.

  The formation of the charge generation layer is not particularly limited, and a known formation method is used. For example, a coating film of a charge generation layer forming coating solution in which the above components are added to a solvent is formed, and the coating film is dried. And heating as necessary. The charge generation layer may be formed by vapor deposition of a charge generation material. Formation of the charge generation layer by vapor deposition is particularly suitable when a condensed ring aromatic pigment or perylene pigment is used as the charge generation material.

  Solvents for preparing the charge generation layer forming coating solution include methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n-acetate. -Butyl, dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, toluene and the like. These solvents are used alone or in combination of two or more.

Examples of a method for dispersing particles (for example, a charge generation material) in a coating solution for forming a charge generation layer include, for example, a media disperser such as a ball mill, a vibrating ball mill, an attritor, a sand mill, a horizontal sand mill, a stirring, an ultrasonic disperser, etc. Medialess dispersers such as roll mills and high-pressure homogenizers are used. Examples of the high-pressure homogenizer include a collision method in which a dispersion liquid is dispersed by liquid-liquid collision or liquid-wall collision in a high pressure state, and a penetration method in which a fine flow path is dispersed in a high pressure state.
In this dispersion, it is effective that the average particle size of the charge generation material in the coating solution for forming the charge generation layer is 0.5 μm or less, preferably 0.3 μm or less, more preferably 0.15 μm or less. .

  Examples of methods for applying the charge generation layer forming coating solution on the undercoat layer (or on the intermediate layer) include blade coating, wire bar coating, spray coating, dip coating, bead coating, and air knife coating. And usual methods such as a curtain coating method.

  The film thickness of the charge generation layer is, for example, preferably set in the range of 0.1 μm to 5.0 μm, more preferably 0.2 μm to 2.0 μm.

(Charge transport layer)
The charge transport layer is, for example, a layer containing a charge transport material and a binder resin. The charge transport layer may be a layer containing a polymer charge transport material.

  Examples of charge transport materials include quinone compounds such as p-benzoquinone, chloranil, bromanyl and anthraquinone; tetracyanoquinodimethane compounds; fluorenone compounds such as 2,4,7-trinitrofluorenone; xanthone compounds; benzophenone compounds A cyanovinyl compound; an electron transporting compound such as an ethylene compound; Examples of the charge transporting material include hole transporting compounds such as triarylamine compounds, benzidine compounds, arylalkane compounds, aryl-substituted ethylene compounds, stilbene compounds, anthracene compounds, and hydrazone compounds. These charge transport materials may be used alone or in combination of two or more, but are not limited thereto.

  As the charge transport material, from the viewpoint of charge mobility, a triarylamine derivative represented by the following structural formula (a-1) and a benzidine derivative represented by the following structural formula (a-2) are preferable.

In Structural Formula (a-1), Ar ^T1 , Ar ^T2 , and Ar ^T3 are each independently a substituted or unsubstituted aryl group, —C ₆ H ₄ —C (R ^T4 ) ═C (R ^T5 ) (R ^T6), or _{-C 6 H 4 -CH = CH-} CH = C (R T7) shows the ^{(R T8).} R ^T4 , R ^T5 , R ^T6 , R ^T7 , and R ^T8 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group.
Examples of the substituent for each group include a halogen atom, an alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms. Examples of the substituent of each group also include a substituted amino group substituted with an alkyl group having 1 to 3 carbon atoms.

In Structural Formula (a-2), R ^T91 and R ^T92 each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms. R ^T101 , R ^T102 , R ^T111 and R ^T112 are each independently ^substituted with a halogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or an alkyl group having 1 to 2 carbon atoms. A substituted amino group, a substituted or unsubstituted aryl group, —C (R ^T12 ) ═C (R ^T13 ) (R ^T14 ), or —CH═CH— ^CH═C (R ^T15 ) (R ^T16 ), R ^T12 , R ^T13 , R ^T14 , R ^T15 and R ^T16 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. Tm1, Tm2, Tn1, and Tn2 each independently represent an integer of 0 or more and 2 or less.
Examples of the substituent for each group include a halogen atom, an alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms. Examples of the substituent of each group also include a substituted amino group substituted with an alkyl group having 1 to 3 carbon atoms.

Here, among the triarylamine derivative represented by the structural formula (a-1) and the benzidine derivative represented by the structural formula (a-2), in particular, “—C ₆ H ₄ —CH═CH—CH═ Triarylamine derivatives having “C (R ^T7 ) (R ^T8 )” and benzidine derivatives having “—CH═CH— ^CH═C (R ^T15 ) (R ^T16 )” are preferable from the viewpoint of charge mobility.

  As the polymer charge transporting material, known materials having charge transporting properties such as poly-N-vinylcarbazole and polysilane are used. In particular, polyester-based polymer charge transport materials disclosed in JP-A-8-176293, JP-A-8-208820 and the like are particularly preferable. The polymer charge transport material may be used alone or in combination with a binder resin.

The binder resin used for the charge transport layer is polycarbonate resin, polyester resin, polyarylate resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl acetate resin, styrene-butadiene copolymer, Vinylidene chloride-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, poly-N -Vinylcarbazole, polysilane, etc. are mentioned. Among these, as the binder resin, a polycarbonate resin or a polyarylate resin is preferable. These binder resins are used alone or in combination of two or more.
The mixing ratio of the charge transport material and the binder resin is preferably 10: 1 to 1: 5 by mass ratio.

  In addition, the charge transport layer may contain a known additive.

  The formation of the charge transport layer is not particularly limited, and a known formation method is used. For example, a coating film of a charge transport layer forming coating solution in which the above components are added to a solvent is formed, and the coating film is dried. This is done by heating as necessary.

  Solvents for preparing the coating solution for forming the charge transport layer include aromatic hydrocarbons such as benzene, toluene, xylene and chlorobenzene; ketones such as acetone and 2-butanone; methylene chloride, chloroform and ethylene chloride. Halogenated aliphatic hydrocarbons: Usual organic solvents such as cyclic or linear ethers such as tetrahydrofuran and ethyl ether. These solvents are used alone or in combination of two or more.

  Coating methods for applying the charge transport layer forming coating solution on the charge generation layer include blade coating method, wire bar coating method, spray coating method, dip coating method, bead coating method, air knife coating method, curtain A usual method such as a coating method may be mentioned.

The thickness of the charge transport layer is, for example, preferably set in the range of 5 μm to 50 μm, more preferably 10 μm to 30 μm.
.

(Protective layer)
The protective layer (outermost surface layer) is the outermost surface layer in the electrophotographic photosensitive member, and includes a cured film of a composition containing two or more types of reactive charge transporting materials, or a reactive charge transporting material and a charge transporting skeleton. It is comprised with the cured film of the composition containing the reactive material which does not have. That is, the protective layer contains a polymer or a crosslinked product (preferably a crosslinked product) of two or more kinds of reactive charge transport materials having different molecular structures, or does not have a reactive charge transport material and a charge transport skeleton. A polymer or cross-linked product (preferably a cross-linked product) of a reactive material is included. Here, even when the outermost surface layer is composed of a cured film of a composition comprising a reactive charge transport material and a reactive material having no charge transport skeleton, both the reactive charge transport material and the reactive material , Two or more different molecular structures may be used in combination.
The protective layer may be composed of a composition further containing other additives such as a non-reactive charge transport material. That is, the protective layer may further contain other additives such as the above-described polymer or crosslinked body (preferably a crosslinked body) and a non-reactive charge transport material.

  The cured film is cured by radical polymerization using heat, light, radiation, or the like. Adjusting the reaction so that it does not progress too quickly improves the mechanical strength and electrical properties of the protective layer (outermost surface layer), and also suppresses the occurrence of film unevenness and wrinkles, so that radical generation is relatively slow. It is preferred to polymerize under the conditions that occur. From this point, thermal polymerization that allows easy adjustment of the polymerization rate is preferred. That is, the composition for forming the cured film constituting the protective layer (outermost surface layer) preferably contains a thermal radical generator or a derivative thereof.

  Hereinafter, the detail of each element of the protective layer (outermost surface layer) comprised with the cured film is demonstrated.

-Reactive charge transport material-
The reactive charge transport material is selected from known materials as long as the compound has a charge transport skeleton and a reactive group in the same molecule. Here, examples of the reactive group include a chain polymerizable group, which may be a functional group capable of radical polymerization, for example, a functional group having a group containing at least a carbon double bond. Specifically, the chain polymerizable group is not particularly limited as long as it is a functional group capable of radical polymerization, for example, a functional group having at least a group containing a carbon double bond. Specific examples include a group containing at least one selected from a vinyl group, a vinyl ether group, a vinyl thioether group, a styryl group, an acryloyl group, a methacryloyl group, and derivatives thereof. Among them, the chain polymerizable functional group is a group containing at least one selected from a vinyl group, a styryl group, an acryloyl group, a methacryloyl group, and derivatives thereof because of its excellent reactivity. Is preferred. Other reactive groups include epoxy groups, —OH, —OR [where R represents an alkyl group], —NH ₂ , —SH, —COOH, —SiR ^Q1 _3-Qn (OR ^Q2 ) _Qn [provided that , R ^Q1 represents a hydrogen atom, an alkyl group, or a substituted or unsubstituted aryl group, and R ^Q2 represents a hydrogen atom, an alkyl group, or a trialkylsilyl group. Well-known reactive groups, such as _Qn represents an integer of 1 to 3, are also included.
The charge transporting skeleton is not particularly limited as long as it is a known structure in an electrophotographic photosensitive member. For example, nitrogen-containing hole transport such as triarylamine compounds, benzidine compounds, and hydrazone compounds is possible. And a structure that is conjugated to a nitrogen atom. Among these, a triarylamine skeleton is preferable.

  As the reactive charge transporting material, a chain polymerizable compound having at least a charge transporting skeleton and a chain polymerizable functional group in the same molecule is preferable from the viewpoint of suppressing density unevenness of an image. In particular, among chain polymerizable compounds, from the viewpoint of electrical properties and mechanical strength, from the same viewpoint, from a specific chain polymerizable charge transport material (chain polymerizable compounds represented by the general formulas (I) and (II)) At least one selected is preferred.

-Specific reactive charge transport material-
The specific reactive charge transport material is at least one selected from the group consisting of reactive compounds represented by the general formulas (I) and (II).

In general formula (I), F represents a charge transporting skeleton.
L represents a divalent linking group containing two or more selected from the group consisting of an alkylene group, an alkenylene group, -C (= O)-, -N (R)-, -S-, and -O-. Show. R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group.
m represents an integer of 1 or more and 8 or less.

In general formula (II), F represents a charge transporting skeleton.
L ′ represents a trivalent or tetravalent group derived from an alkane or alkene, and an alkylene group, alkenylene group, —C (═O) —, —N (R) —, —S—, and —O—. And an (n + 1) -valent linking group containing two or more selected from the group consisting of: R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. The trivalent or tetravalent group derived from alkane or alkene means a group obtained by removing three or four hydrogen atoms from alkane or alkene. The same applies hereinafter.
m ′ represents an integer of 1 to 6. n represents an integer of 2 or more and 3 or less.

  In general formulas (I) and (II), F represents a charge transporting skeleton, that is, a structure having charge transporting properties. Specifically, phthalocyanine compounds, porphyrin compounds, azobenzene compounds, triarylamine compounds Examples thereof include structures having charge transporting properties such as compounds, benzidine compounds, arylalkane compounds, aryl-substituted ethylene compounds, stilbene compounds, anthracene compounds, hydrazone compounds, quinone compounds, and fluorenone compounds.

In general formula (I), examples of the linking group represented by L include:
A divalent linking group in which —C (═O) —O— is interposed in the alkylene group,
A divalent linking group in which —C (═O) —N (R) — is interposed in an alkylene group,
A divalent linking group in which —C (═O) —S— is interposed in the alkylene group,
A divalent linking group in which -O- is interposed in the alkylene group,
A divalent linking group in which -N (R)-is interposed in the alkylene group,
A divalent linking group in which -S- is interposed in the alkylene group,
Is mentioned.
The linking group represented by L is an alkylene group, -C (= O) -O-, -C (= O) -N (R)-, -C (= O) -S-, -O. Two groups of-or -S- may be present.

Specific examples of the linking group represented by L in the general formula (I) include:
* — (CH ₂ ) _p —C (═O) —O— (CH ₂ ) _q —,
_{* - (CH 2) p -O} -C (= O) - (CH 2) r -C (= O) -O- (CH 2) q -,
* — (CH ₂ ) _p —C (═O) —N (R) — (CH ₂ ) _q —,
_{* - (CH 2) p -C} (= O) -S- (CH 2) q -,
_{* - (CH 2) p -O-} (CH 2) q -,
_{* - (CH 2) p -N} (R) - (CH 2) q -,
_{* - (CH 2) p -S-} (CH 2) q -,
_{* - (CH 2) p -O-} (CH 2) r -O- (CH 2) q -
Etc.
Here, in the linking group represented by L, p represents 0 or an integer of 1 to 6 (preferably 1 to 5). q represents an integer of 1 to 6 (preferably 1 to 5). r represents an integer of 1 to 6 (preferably 1 to 5).
In the linking group represented by L, “*” represents a site linked to F.

On the other hand, in the general formula (II), as the linking group represented by L ′, for example,
A (n + 1) -valent linking group in which —C (═O) —O— is interposed in a branchedly linked alkylene group,
A (n + 1) -valent linking group in which —C (═O) —N (R) — is interposed in a branchedly linked alkylene group,
A (n + 1) -valent linking group in which —C (═O) —S— is interposed in a branchedly linked alkylene group,
(N + 1) -valent linking group in which —O— is interposed in a branched alkylene group,
A (n + 1) -valent linking group in which —N (R) — is interposed in a branchedly linked alkylene group,
A (n + 1) -valent linking group in which -S- is interposed in a branched alkylene group;
Is mentioned.
Note that the linking group represented by L ′ is a branched alkylene group in which —C (═O) —O—, —C (═O) —N (R) —, —C (═O ) Two groups of -S-, -O-, or -S- may be present.

In the general formula (II), as the linking group represented by L ′, for example,
* — (CH ₂ ) _p —CH [C (═O) —O— (CH ₂ ) _q —] ₂ ,
* — (CH ₂ ) _p —CH═C [C (═O) —O— (CH ₂ ) _q —] ₂ ,
_{* - (CH 2) p -CH} [C (= O) -N (R) - (CH 2) q -] 2,
_{* - (CH 2) p -CH} [C (= O) -S- (CH 2) q -] 2,
* — (CH ₂ ) _p —CH [(CH ₂ ) _r —O— (CH ₂ ) _q —] ₂ ,
_{* - (CH 2) p -CH} = C [(CH 2) r -O- (CH 2) q -] 2,
_{* - (CH 2) p -CH} [(CH 2) r -N (R) - (CH 2) q -] 2,
_{* - (CH 2) p -CH} [(CH 2) r -S- (CH 2) q -] 2,


* — (CH ₂ ) _p —O—C [(CH ₂ ) _r —O— (CH ₂ ) _q —] ₃
* — (CH ₂ ) _p —C (═O) —O—C [(CH ₂ ) _r —O— (CH ₂ ) _q —] ₃
Etc.
Here, in the linking group represented by L ′, p represents 0 or an integer of 1 to 6 (preferably 1 to 5). q represents an integer of 1 to 6 (preferably 1 to 5). r represents an integer of 1 to 6 (preferably 1 to 5). s represents an integer of 1 to 6 (preferably 1 to 5).
In the linking group represented by L ′, “*” represents a site linked to F.

Among these, in the general formula (II), as the linking group represented by L ′,
* — (CH ₂ ) _p —CH [C (═O) —O— (CH ₂ ) _q —] ₂ ,
* — (CH ₂ ) _p —CH═C [C (═O) —O— (CH ₂ ) _q —] ₂ ,
* — (CH ₂ ) _p —CH [(CH ₂ ) _r —O— (CH ₂ ) _q —] ₂ ,
_{* - (CH 2) p -CH} = C [(CH 2) r -O- (CH 2) q -] 2,
Is good.
Specifically, the group connected to the charge transporting skeleton represented by F of the reactive compound represented by the general formula (II) (corresponding to the group represented by the general formula (IIA-a)) is represented by the following general formula ( It may be a group represented by IIA-a1), the following general formula (IIA-a2), the following general formula (IIA-a3), or the following general formula (IIA-a4).

In general formula (IIA-a1) or (IIA-a2), ^Xk1 represents a divalent linking group. kq1 represents an integer of 0 or 1. X ^k2 represents a divalent linking group. kq2 represents an integer of 0 or 1.
Here, the divalent linking group represented by X ^k1 and X ^k2 is, for example, — (CH ₂ ) _p — (wherein p represents an integer of 1 to 6 (preferably 1 to 5))). Can be mentioned. Examples of the divalent linking group also include an alkyleneoxy group.

In general formula (IIA-a3) or (IIA-a4), ^Xk3 represents a divalent linking group. kq3 represents an integer of 0 or 1. X ^k4 represents a divalent linking group. kq4 represents an integer of 0 or 1.
Here, the divalent linking group represented by X ^k3 and X ^k4 is, for example, — (CH ₂ ) _p — (wherein p represents an integer of 1 to 6 (preferably 1 to 5))). Can be mentioned. Examples of the divalent linking group also include an alkyleneoxy group.

In general formulas (I) and (II), in the linking group represented by L or L ′, the alkyl group represented by R of “—N (R) —” has 1 to 5 carbon atoms (preferably 1 4 or less) linear and branched alkyl groups, and specific examples include a methyl group, an ethyl group, a propyl group, and a butyl group.
Examples of the aryl group represented by R in “—N (R) —” include aryl groups having 6 to 15 carbon atoms (preferably 6 to 12 carbon atoms). Specific examples include phenyl groups and toluyl groups. Group, xylyl group, naphthyl group and the like.
Examples of the aralkyl group include aralkyl groups having 7 to 15 carbon atoms (preferably 7 to 14 carbon atoms). Specific examples include a benzyl group, a phenethyl group, and a biphenylmethylene group.

In general formulas (I) and (II), m preferably represents an integer of 1 to 6.
m ′ preferably represents an integer of 1 to 6.
n preferably represents an integer of 2 or more and 3 or less.

Next, preferred compounds of the reactive compounds represented by the general formulas (I) and (II) will be described.
As the reactive compound represented by the general formulas (I) and (II), a reactive compound having a charge transporting skeleton (structure having charge transporting property) derived from a triarylamine compound as F is preferable.
Specifically, the reactive compound represented by the general formula (I) includes the general formula (Ia), the general formula (Ib), the general formula (Ic), and the general formula (Id). At least one compound selected from the group consisting of reactive compounds represented by
On the other hand, as the reactive compound represented by the general formula (II), the reactive compound represented by the general formula (II-a) is preferable.

-Reactive compound shown by general formula (Ia) The reactive compound shown by general formula (Ia) is demonstrated.
When the reactive compound represented by the general formula (Ia) is applied as the specific reactive charge transport material, it is easy to suppress deterioration of electrical characteristics due to environmental changes. The reason is not clear, but is thought to be as follows.
First, since the reactive compound having a (meth) acrylic group that has been used conventionally has a strong hydrophilicity of the (meth) acrylic group with respect to a skeleton part that expresses charge transport performance during polymerization, It is considered that a certain kind of layer separation state is formed, which hinders hopping conduction. For this reason, a charge transporting film containing a polymer of a reactive compound having a (meth) acrylic group or a crosslinked product has a reduced efficiency of charge transport, and further has a reduced environmental stability due to partial moisture adsorption or the like. It is considered a thing.
On the other hand, the reactive compound represented by the general formula (Ia) has a vinyl-based chain polymerizable group that is not strongly hydrophilic, and further has a skeleton that exhibits charge transport performance within one molecule. The skeletons are linked by a flexible linking group that does not have a conjugated bond such as an aromatic ring or a conjugated double bond. Since it has such a structure, it is considered that efficient charge transport performance and high strength can be achieved, and formation of a layer separation state during polymerization is suppressed. As a result, the protective layer (outermost surface layer) containing the polymer or cross-linked product of the reactive compound represented by the general formula (Ia) is excellent in both charge transport performance and mechanical strength. It is thought that the environment dependence (temperature and humidity dependence) of transport performance can be reduced.
From the above, it is considered that when the reactive compound represented by the general formula (Ia) is applied, deterioration of electrical characteristics due to environmental changes is easily suppressed.

In the general formula (Ia), Ar ^{a1 to} Ar ^a4 each independently represent a substituted or unsubstituted aryl group. Ar ^a5 and Ar ^a6 each independently represent a substituted or unsubstituted arylene group. Xa represents a divalent linking group formed by combining groups selected from an alkylene group, -O-, -S-, and an ester. Da represents a group represented by the following general formula (IA-a). ac1 to ac4 each independently represents an integer of 0 or more and 2 or less. However, the total number of Da is 1 or 2.

In the general formula ^{(IA-a), L} a _{is, * - (CH 2) an} -O-CH 2 - is represented by the divalent linking group linked to the group represented by ^Ar a1 ^{to Ar a4} at * Indicates. an represents an integer of 1 or 2.

Details of the general formula (Ia) will be described below.
In general formula (Ia), the substituted or unsubstituted aryl groups represented by Ar ^{a1 to} Ar ^a4 may be the same or different.
Here, as a substituent in the substituted aryl group, other than “Da”, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, and an alkoxy group having 1 to 4 carbon atoms. Examples thereof include a substituted phenyl group, an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, and a halogen atom.

In general formula (Ia), Ar ^{a1 to} Ar ^a4 are preferably any one of the following structural formulas (1) to (7).
In addition, the following structural formulas (1) to (7) collectively indicate “— (Da) _ac1 ” to “— (Da) _ac1 ” that can be connected to each of Ar ^{a1 to} Ar ^a4. ) _C ”.

In the structural formulas (1) to (7), R ¹¹ is substituted with a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. And a phenyl group, an unsubstituted phenyl group, and an aralkyl group having 7 to 10 carbon atoms. R ¹² and R ¹³ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group substituted with an alkoxy group having 1 to 4 carbon atoms. 1 group selected from the group consisting of an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, and a halogen atom. R ¹⁴ each independently represents an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group substituted with an alkoxy group having 1 to 4 carbon atoms, an unsubstituted phenyl group, 1 type chosen from the group which consists of a C7-C10 aralkyl group and a halogen atom is shown. Ar represents a substituted or unsubstituted arylene group. s represents 0 or 1. t represents an integer of 0 or more and 3 or less. Z ′ represents a divalent organic linking group.

  Here, in the formula (7), Ar is preferably one represented by the following structural formula (8) or (9).

In structural formulas (8) and (9), R ¹⁵ and R ¹⁶ are each independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. Represents one selected from the group consisting of a phenyl group substituted with a group, an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, and a halogen atom, and t1 and t2 each represent an integer of 0 to 3 Show.

  In the formula (7), Z ′ is preferably one represented by any of the following structural formulas (10) to (17).

In Structural Formulas (10) to (17), R ¹⁷ and R ¹⁸ are each independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. 1 type selected from the group consisting of a phenyl group substituted with a group, an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, and a halogen atom. W represents a divalent group. q1 and r1 each independently represents an integer of 1 or more and 10 or less. t3 and t4 each represent an integer of 0 or more and 3 or less.

  In the structural formulas (16) to (17), W is preferably any one of divalent groups represented by the following structural formulas (18) to (26). However, in Formula (25), u shows the integer of 0-3.

In the general formula (Ia), in the substituted or unsubstituted arylene group represented by Ar ^a5 and Ar ^a6 , the arylene group is a target position from the aryl group exemplified in the description of Ar ^{a1 to} Ar ^a4. And an arylene group in which one hydrogen atom is removed.
Moreover, as a substituent in a substituted arylene group, it is the same as that of what is mentioned as substituents other than "Da" in a substituted aryl group by description of Ar < ^a1 > -Ar < ^a4 >.

In general formula (Ia), the divalent linking group represented by Xa is an alkylene group or a divalent group formed by combining alkylene groups, —O—, —S—, and groups selected from esters. Thus, the linking group does not contain a conjugated bond such as an aromatic ring or a conjugated double bond.
Specifically, examples of the divalent linking group represented by Xa include an alkylene group having 1 to 10 carbon atoms, and an alkylene group having 1 to 10 carbon atoms and —O—, —S—, and —O. A divalent group formed by combining a group selected from —C (═O) — and —C (═O) —O— is also included.
When the divalent linking group represented by Xa is an alkylene group, the alkylene group may have a substituent such as alkyl, alkoxy, halogen, etc., and two of these substituents are bonded to each other, A structure such as a divalent linking group represented by Structural Formula (26) described as a specific example of W in Structural Formulas (16) to (17) may be used.

-Reactive compound shown by general formula (Ib) The reactive compound shown by general formula (Ib) is demonstrated.
When the reactive compound represented by the general formula (Ib) is applied as a specific reactive charge transporting material, wear of the protective layer (outermost surface layer) is suppressed and occurrence of density unevenness in the image is easily suppressed. Become. The reason is not clear, but is thought to be as follows.
First, the bulky charge transport skeleton and the polymerization site (styryl group) are structurally close, and if it is rigid, the polymerization sites will not move easily, and residual strain due to the curing reaction tends to remain, and the charge transport skeleton is distorted. As a result, a change in the level of HOMO (the highest occupied orbit) that leads to carrier transport occurs, and as a result, the energy distribution is likely to be widened (energy disorder: σ is large).
On the other hand, through a methylene group and an ether group, flexibility is obtained in the molecular structure, and a small σ is easily obtained. Further, the methylene group and the ether group are compared with an ester group, an amide group, etc. The dipole moment (dipole moment) is small, and this effect also contributes to the reduction of σ and is considered to improve the electrical characteristics. In addition, it is considered that the flexibility of the molecular structure increases the degree of freedom of movement of the reaction site (reaction site), and the reaction rate also improves, resulting in a strong film. A structure in which a flexible connecting chain is interposed between the polymerization sites is preferable.
For this reason, it is considered that the reactive compound represented by the general formula (Ib) increases the molecular weight of the molecule itself due to the curing reaction, makes the center of gravity difficult to move, and has a high degree of freedom of the styryl group. As a result, the protective layer (outermost surface layer) containing the polymer or crosslinked product of the reactive compound represented by the general formula (Ib) is considered to have excellent electrical properties and high strength.
From the above, it is considered that when the reactive compound represented by the general formula (Ib) is applied, wear of the protective layer (outermost surface layer) is suppressed and occurrence of uneven density in the image is easily suppressed.

In the general formula (Ib), Ar ^{b1 to} Ar ^b4 each independently represent a substituted or unsubstituted aryl group. Ar ^b5 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted arylene group. Db represents a group represented by the following general formula (IA-b). bc1 to bc5 each independently represent an integer of 0 or more and 2 or less. bk represents 0 or 1. However, the total number of Db is 1 or 2.

In General Formula (IA-b), L ^b includes a group represented by * — (CH ₂ ) _bn —O—, and is a divalent linking group linked to a group represented by Ar ^{b1 to} Ar ^b5 at *. Indicates. bn represents an integer of 3 to 6.

Hereinafter, the details of the general formula (Ib) will be described.
In general formula (Ib), the substituted or unsubstituted aryl group represented by Ar ^{b1 to} Ar ^b4 is the substituted or unsubstituted aryl group represented by Ar ^{a1 to} Ar ^a4 in general formula (Ia). It is the same.
Ar ^b5 represents a substituted or unsubstituted aryl group when bk is 0, and examples of the substituted or unsubstituted aryl group include substituted or unsubstituted Ar ^{a1 to} Ar ^a4 in the general formula (Ia) Same as unsubstituted aryl group.
Ar ^b5 represents a substituted or unsubstituted arylene group when bk is 1, and the substituted or unsubstituted arylene group includes a substituent represented by Ar ^a5 and Ar ^a6 in the general formula (Ia) or The same as the unsubstituted arylene group.

Next, the details of the general formula (IA-b) will be described.
In the general formula (IA-b), examples of the divalent linking group represented by ^{L b,} for example,
* — (CH ₂ ) _bp —O—,
* — (CH ₂ ) _bp —O— (CH ₂ ) _bq —O—
Etc.
Here, in the linking group represented by L ^b, bp represents an integer of 3 to 6 (preferably 3 to 5). bq represents an integer of 1 to 6 (preferably 1 to 5).
Incidentally, in the linking group represented by ^{L b, "*"} represents a site connecting to a group represented by Ar b1 ^{to Ar b5.}

-Reactive compound shown by general formula (Ic) The reactive compound shown by general formula (Ic) is demonstrated.
When the reactive compound represented by the general formula (Ic) is applied as the specific reactive charge transporting material, scratches are hardly generated on the surface even when used repeatedly, and image quality deterioration is easily suppressed. The reason is not clear, but is thought to be as follows.
First, when forming the outermost surface layer containing a polymer or cross-linked product of a specific reactive charge transport material, film shrinkage accompanying the polymerization reaction or cross-linking reaction, and structure around the charge transport structure and chain polymerizable group It is thought that aggregation occurs. Therefore, when the surface of the electrophotographic photosensitive member is subjected to a mechanical load by repeated use, the film itself is worn or the chemical structure in the molecule is cut, so that the film contraction and aggregation state change, and the electrophotographic photosensitive member changes. It is considered that the electrical characteristics of the image change and cause image quality degradation.
On the other hand, since the reactive compound represented by the general formula (Ic) has a styrene skeleton as a chain polymerizable group, it has good compatibility with the aryl group which is the main skeleton of the charge transport material, and the film shrinks. It is considered that the aggregation of the charge transport structure and the structure around the chain polymerizable group due to polymerization reaction or crosslinking reaction is suppressed. As a result, the electrophotographic photosensitive member having a protective layer (outermost surface layer) containing a polymer or crosslinked product of the reactive compound represented by the general formula (Ic) is considered to suppress image quality deterioration due to repeated use. It is done.
In addition, the reactive compound represented by the general formula (Ic) includes a charge transporting skeleton and a styrene skeleton, a specific group such as —C (═O) —, —N (R) —, and —S—. It is thought that the interaction between the specific group and the nitrogen atom in the charge transporting skeleton, the interaction between the specific groups, and the like are caused by linking via the linking group including, as a result, the general formula (I- It is thought that the strength of the protective layer (outermost surface layer) containing the polymer or crosslinked product of the reactive compound represented by c) is further improved.
From the above, it is considered that when the reactive compound represented by the general formula (Ic) is applied, scratches are hardly generated on the surface even when used repeatedly, and image quality deterioration is easily suppressed.
Note that specific groups such as -C (= O)-, -N (R)-, and -S- are attributed to the polarity and hydrophilicity, causing the charge transportability and image quality deterioration under high humidity conditions. However, since the reactive compound represented by the general formula (Ic) has a styrene skeleton having higher hydrophobicity than (meth) acryl or the like as a chain polymerizable group, the charge transportability is deteriorated or the previous cycle is deteriorated. It is considered that image quality deterioration such as an afterimage phenomenon (ghost) due to the history hardly occurs.

In the general formula (Ic), Ar ^{c1 to} Ar ^c4 each independently represent a substituted or unsubstituted aryl group. Ar ^c5 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted arylene group. Dc represents a group represented by the following general formula (IA-c). cc1 to cc5 each independently represents an integer of 0 or more and 2 or less. ck represents 0 or 1. However, the total number of Dc is 1 or more and 8 or less.

In the general formula (IA-c), ^{L C} is, -C (= O) -, - N (R) -, - S-, and, -C (= O) - and -O -, - N (R )-Or -S- represents a divalent linking group containing one or more groups selected from the group consisting of groups. R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group.

Details of the general formula (Ic) will be described below.
In general formula (Ic), the substituted or unsubstituted aryl group represented by Ar ^{c1 to} Ar ^c4 is a substituted or unsubstituted aryl group represented by Ar ^{a1 to} Ar ^a4 in general formula (Ia). It is the same.
Ar ^c5 represents a substituted or unsubstituted aryl group when ck is 0, and examples of the substituted or unsubstituted aryl group include a substituted group represented by Ar ^{a1 to} Ar ^a4 in formula (Ia) or Same as unsubstituted aryl group.
Ar ^c5 represents a substituted or unsubstituted arylene group when ck is 1, and the substituted or unsubstituted arylene group includes a substituent represented by Ar ^a5 and Ar ^a6 in formula (Ia) or The same as the unsubstituted arylene group.
The total number of Dc is preferably 2 or more, more preferably 4 or more, from the viewpoint of obtaining a protective layer (outermost surface layer) with higher strength. In general, if the number of chain polymerizable groups in one molecule is too large, as the polymerization (crosslinking) reaction proceeds, the molecules become difficult to move and the chain polymerization reactivity decreases, and the proportion of unreacted chain polymerizable groups increases. Therefore, the total number of Dc is preferably 7 or less, more preferably 6 or less.

Next, the details of the general formula (IA-c) will be described.
In the general formula (IA-c), ^examples of the divalent linking group represented by L ^c include —C (═O) —, —N (R) —, —S—, and —C (═O) —. And a divalent linking group containing a group in which —O—, —N (R) —, or —S— is combined (hereinafter referred to as “specific linking group”).
Here, the specific linking group includes, for example, —C (═O) —, —N (R) —, and —S— from the viewpoint of the balance between the strength and polarity (hydrophobicity) of the protective layer (outermost surface layer). , -C (= O) -O-, -C (= O) -N (R)-, -C (= O) -S-, -O-C (= O) -O-, -O-C (═O) —N (R) — is preferred, preferably —N (R) —, —S—, —C (═O) —O—, —C (═O) —N (H) —, — C (= O) -O-, more preferably -C (= O) -O-.
Examples of the divalent linking group represented by L ^c include a specific linking group, a saturated hydrocarbon (including linear, branched, and cyclic) or aromatic hydrocarbon residue, oxygen, and the like. And a divalent linking group formed by combining atoms with each other. Among these, a specific linking group, a linear saturated hydrocarbon residue, and an oxygen atom are used in combination. A valent linking group is preferred.
The total number of carbon atoms contained in the divalent linking group represented by L ^c is, for example, from 1 to 20 in terms of the density of the styrene skeleton in the molecule and chain polymerization reactivity, and preferably from 2 to 10 It is as follows.

Specific examples of the divalent linking group represented by L ^c in the general formula (IA-c) include, for example,
_{* - (CH 2) cp -C} (= O) -O- (CH 2) cq -,
* — (CH ₂ ) _cp —O—C (═O) — (CH ₂ ) _cr —C (═O) —O— (CH ₂ ) _cq —,
* — (CH ₂ ) _cp —C (═O) —N (R) — (CH ₂ ) _cq —,
_{* - (CH 2) cp -C} (= O) -S- (CH 2) cq -,
_{* - (CH 2) cp -N} (R) - (CH 2) cq -,
_{* - (CH 2) cp -S-} (CH 2) cq -,
Etc.
Here, in the linking group represented by ^{L c,} cp is 0, or 1 to 6 (preferably 1 to 5) represents an integer of. cq represents an integer of 1 to 6 (preferably 1 to 5). cr represents an integer of 1 to 6 (preferably 1 to 5).
In the linking group represented by L ^c , “*” represents a site linked to the group represented by Ar ^{c1 to} Ar ^c5 .

Among these, in the general formula (IA-c), the divalent linking group represented by ^{_{L c, * - (CH 2}} ) cp -C (= O) -O-CH 2 - is preferred. That is, the group represented by the general formula (IA-c) is preferably a group represented by the following general formula (IA-c1). However, in general formula (IA-c1), cp1 shows the integer of 0-4.

-Reactive compound shown by general formula (Id) The reactive compound shown by general formula (Id) is demonstrated.
When the reactive compound represented by the general formula (Id) is applied as the specific reactive charge transporting material, wear of the protective layer (outermost surface layer) is suppressed and generation of density unevenness in the image is easily suppressed. Become. Although the reason is not certain, it is thought to be due to the same reason as the reactive compound represented by the general formula (Ib).
In particular, the reactive compound represented by the general formula (Id) has a higher total number of Dd of 3 or more and 8 or less than the general formula (Ib). It is considered that a crosslinked network is easily formed, and wear of the protective layer (outermost surface layer) is more easily suppressed.

In the general formula (Id), Ar ^{d1 to} Ar ^d4 each independently represent a substituted or unsubstituted aryl group. Ar ^d5 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted arylene group. Dd represents a group represented by the following general formula (IA-d). dc1 to dc5 each independently represents an integer of 0 or more and 2 or less. dk represents 0 or 1. However, the total number of Dd is 3 or more and 8 or less.

In General Formula (IA-d), L ^d includes a group represented by * — (CH ₂ ) _dn —O—, and represents a divalent linking group that is coupled to Ar ^{d1 to} Ar ^d5 by *. Show. dn represents an integer of 1 to 6.

Details of the general formula (Id) will be described below.
In general formula (Id), the substituted or unsubstituted aryl group represented by Ar ^{d1 to} Ar ^d4 is the substituted or unsubstituted aryl group represented by Ar ^{a1 to} Ar ^a4 in general formula (Ia). It is the same.
Ar ^d5 represents a substituted or unsubstituted aryl group when dk is 0, and examples of the substituted or unsubstituted aryl group include substituted or unsubstituted Ar ^{a1 to} Ar ^a4 in the general formula (Ia) Same as unsubstituted aryl group.
Ar ^d5 represents a substituted or unsubstituted arylene group when dk is 1, and the substituted or unsubstituted arylene group includes a substituent represented by Ar ^a5 and Ar ^a6 in the general formula (Ia) or The same as the unsubstituted arylene group.
The total number of Dd is preferably 4 or more from the viewpoint of obtaining a protective layer (outermost surface layer) with higher strength.

Next, the details of the general formula (IA-d) will be described.
In the general formula (IA-d), examples of the divalent linking group represented by L ^d include:
* — (CH ₂ ) _dp —O—,
_{* - (CH 2) dp -O-} (CH 2) dq -O-
Etc.
Here, in the linking group represented by L ^d , dp represents an integer of 1 to 6 (preferably 1 to 5). dq represents an integer of 1 to 6 (preferably 1 to 5).
In the linking group represented by L ^d , “*” represents a site linked to the group represented by Ar ^{d1 to} Ar ^d5 .

-Reactive compound shown by general formula (II-a) The reactive compound shown by general formula (II-a) is demonstrated.
When a reactive compound represented by the general formula (II) (particularly the general formula (II-a)) is applied as a specific reactive charge transport material, it is easy to suppress deterioration of electrical characteristics even when used repeatedly over a long period of time. Become. The reason is not clear, but is thought to be as follows.
First, the reactive compound represented by the general formula (II) (particularly the general formula (II-a)) has two or three chain polymerizable reactive groups from a charge transporting skeleton through one linking group. It is a compound having (styrene group).
Therefore, the reactive compound represented by the general formula (II) (particularly the general formula (II-a)) was polymerized or cross-linked by the presence of this linking group while maintaining a high degree of curing and the number of cross-linking sites. At this time, it is difficult to cause distortion in the charge transporting skeleton, and it is considered that it is easy to realize both high curing degree and excellent charge transport performance.
In addition, conventionally used charge transporting compounds having a (meth) acryl group are likely to be distorted as described above, and the reactive sites are highly hydrophilic and the charge transporting sites are highly hydrophobic. Therefore, the reactive compound represented by the general formula (II) (particularly the general formula (II-a)) has a styrene group as a reactive group, whereas microscopic phase separation (microphase separation) is likely to occur. Furthermore, the structure has a linking group that is difficult to cause distortion in the charge transporting skeleton when cured (crosslinked), and both the reactive site and the charge transporting site are hydrophobic. Since separation is difficult to occur, it is considered that efficient charge transport performance and high strength can be achieved. As a result, the protective layer (outermost surface layer) containing a polymer or a crosslinked product of the reactive compound represented by the general formula (II) (particularly the general formula (II-a)) has excellent mechanical strength and charge. It is considered that the transport performance (electrical characteristics) is more excellent.
From the above, it is considered that when the reactive compound represented by the general formula (II) (particularly, the general formula (II-a)) is applied, deterioration of electric characteristics is easily suppressed even when used repeatedly over a long period of time.

In the general formula (II-a), Ar ^{k1 to} Ar ^k4 each independently represents a substituted or unsubstituted aryl group. Ar ^k5 represents a substituted or unsubstituted aryl group, or a substituted or unsubstituted arylene group. Dk represents a group represented by the following general formula (IIA-a). kc1 to kc5 each independently represents an integer of 0 or more and 2 or less. kk represents 0 or 1. However, the total number of Dk is 1 or more and 8 or less.

In the general formula (IIA-a), L ^k represents a trivalent or tetravalent group derived from an alkane or alkene, an alkylene group, an alkenylene group, -C (= O)-, -N (R)- A (kn + 1) -valent linking group containing two or more selected from the group consisting of, -S-, and -O-. R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. kn represents an integer of 2 or more and 3 or less.

Hereinafter, the details of the general formula (II-a) will be described.
In general formula (II-a), the substituted or unsubstituted aryl group represented by Ar ^{k1 to} Ar ^k4 is the substituted or unsubstituted aryl group represented by Ar ^{a1 to} Ar ^a4 in general formula (Ia). It is the same.
Ar ^k5 represents a substituted or unsubstituted aryl group when kk is 0. ^Examples of the substituted or unsubstituted aryl group include substituted or unsubstituted Ar ^{a1 to} Ar ^a4 in the general formula (Ia) Same as unsubstituted aryl group.
Ar ^k5 represents a substituted or unsubstituted arylene group when kk is 1, and the substituted or unsubstituted arylene group includes a substituent represented by Ar ^a5 and Ar ^a6 in the general formula (Ia) or The same as the unsubstituted arylene group.
The total number of Dk is preferably 2 or more, more preferably 4 or more, from the viewpoint of obtaining a protective layer (outermost surface layer) with higher strength. In general, if the number of chain polymerizable groups in one molecule is too large, as the polymerization (crosslinking) reaction proceeds, the molecules become difficult to move and the chain polymerization reactivity decreases, and the proportion of unreacted chain polymerizable groups increases. Therefore, the total number of Dk is preferably 7 or less, more preferably 6 or less.

Next, the detail of general formula (IIA-a) is demonstrated.
In the general formula (IIA-a), the (kn + 1) -valent linking group ^represented by L ^k is, for example, the same as the (n + 1) -valent linking group represented by L ′ in the general formula (II).

Specific examples of the specific reactive charge transport material are shown below.
Specifically, the charge transporting skeleton F of the general formulas (I) and (II) (for example, a portion corresponding to the skeleton excluding Da in the general formula (Ia) and Dk of the general formula (II-a)). Together with specific examples of functional groups linked to the charge transporting skeleton F (for example, a site corresponding to Da in the general formula (Ia) or Dk in the general formula (II-a)). Specific examples of the reactive compound represented by (II) and (II) are shown below, but are not limited thereto.
In the specific examples of the charge transporting skeleton F in the general formulas (I) and (II), the “*” part means that the “*” part of the functional group linked to the charge transporting skeleton F is linked. To do.
That is, for example, the exemplary compound (Ib) -1 is shown as a specific example of the charge transporting skeleton F: (M1) -1, and a specific example of the functional group: (R2) -1. The typical structure shows the following structure.

  First, specific examples of the charge transporting skeleton F are shown below.

  Next, specific examples of the functional group linked to the charge transporting skeleton F are shown.

  Next, specific examples of the compound represented by the general formula (I), specifically, the general formula (Ia) are shown.

  Next, specific examples of the compound represented by the general formula (I), specifically, the general formula (Ib) are shown.

  Next, specific examples of the compound represented by the general formula (I), specifically, the general formula (Ic) are shown.

  Next, specific examples of the compound represented by the general formula (I), specifically, the general formula (Id) will be shown.

  Next, specific examples of the compound represented by the general formula (II), specifically, the general formula (II-a) are shown.

A specific chain polymerizable charge transport material (particularly, a chain polymerizable compound represented by the general formula (I)) is synthesized, for example, as follows.
That is, a specific chain polymerizable charge transport material is synthesized by etherification with a carboxylic acid or alcohol as a precursor and a corresponding chloromethylstyrene or the like.

  An example of the synthesis route of the exemplary compound (Id) -22 of a specific chain polymerizable charge transport material is shown below.

The arylamine compound carboxylic acid is an ester group of an arylamine compound, for example, as described in Experimental Chemistry Course, 4th edition, volume 20, p. As described in No. 51 and the like, it can be obtained by hydrolysis using a basic catalyst (NaOH, K ₂ CO ₃ etc.) and an acidic catalyst (eg phosphoric acid, sulfuric acid etc.).
In this case, various solvents can be used, and it is preferable to use alcohols such as methanol, ethanol, ethylene glycol, or a mixture of water.
Furthermore, when the solubility of the arylamine compound is low, methylene chloride, chloroform, toluene, dimethyl sulfoxide, ether, tetrahydrofuran or the like may be added.
Although there is no restriction | limiting in particular in the quantity of a solvent, For example, it is 1 mass part or more and 100 mass parts or less with respect to 1 mass part of arylamine compounds containing an ester group, Preferably it is used by 2 mass parts or more and 50 mass parts or less. Good.
The reaction temperature is set, for example, in the range from room temperature (for example, 25 ° C.) to the boiling point of the solvent, and is preferably 50 ° C. or higher in view of the reaction rate.
Although there is no restriction | limiting in particular about the quantity of a catalyst, For example, 0.001 mass part or more and 1 mass part or less with respect to 1 mass part of arylamine compounds containing an ester group, Preferably it is 0.01 mass part or more and 0.5 It is good to use below mass parts.
When hydrolysis is performed with a basic catalyst after the hydrolysis reaction, the generated salt is neutralized with an acid (for example, hydrochloric acid or the like) and released. Furthermore, after washing thoroughly with water, use after drying, or if necessary, recrystallize and purify with an appropriate solvent such as methanol, ethanol, toluene, ethyl acetate, acetone, etc. Also good.

  The alcohol form of the arylamine compound may be prepared by reacting the ester group of the arylamine compound with, for example, Experimental Chemistry Course, Fourth Edition, Volume 20, As described in No. 10 and the like, it is synthesized by reducing to the corresponding alcohol using lithium aluminum hydride, sodium borohydride or the like.

  For example, when a reactive group is introduced by an ester bond, normal esterification in which an arylamine compound carboxylic acid and hydroxymethylstyrene are dehydrated and condensed with an acid catalyst, an arylamine compound carboxylic acid, and a halogenated methylstyrene are combined. , Pyridine, piperidine, triethylamine, dimethylaminopyridine, trimethylamine, DBU, sodium hydride, sodium hydroxide, potassium hydroxide and other methods of condensation can be used. This is preferred because the product is suppressed.

The halogenated methylstyrene is preferably added in an amount of 1 equivalent or more, preferably 1.2 equivalents or more, more preferably 1.5 equivalents or more with respect to the acid of the arylamine compound carboxylic acid. It is preferably used in an amount of from 8 equivalents to 2.0 equivalents, preferably from 1.0 equivalents to 1.5 equivalents.
Solvents include aprotic polar solvents such as N-methylpyrrolidone, dimethyl sulfoxide, N, N-dimethylformamide, ketone solvents such as acetone and methyl ethyl ketone, ether solvents such as diethyl ether and tetrahydrofuran, toluene, chlorobenzene, 1 An aromatic solvent such as chloronaphthalene is effective, and is in the range of 1 to 100 parts by weight, preferably 2 to 50 parts by weight, based on 1 part by weight of the arylamine compound carboxylic acid. It should be used.
The reaction temperature is not particularly limited. After completion of the reaction, the reaction solution is poured into water, extracted with a solvent such as toluene, hexane, or ethyl acetate, washed with water, and further purified using an adsorbent such as activated carbon, silica gel, porous alumina, or activated clay if necessary. May be.

In addition, when introduced by an ether bond, arylamine compound alcohol and halogenated methylstyrene are converted into bases such as pyridine, piperidine, triethylamine, dimethylaminopyridine, trimethylamine, DBU, sodium hydride, sodium hydroxide, potassium hydroxide, etc. It is preferable to use a method of condensing with.
The halogenated methylstyrene is preferably added in an amount of 1 equivalent or more, preferably 1.2 equivalents or more, more preferably 1.5 equivalents or more with respect to the alcohol of the arylamine compound alcohol. It is 8 to 2.0 equivalents, preferably 1.0 to 1.5 equivalents.
Solvents include aprotic polar solvents such as N-methylpyrrolidone, dimethyl sulfoxide, N, N-dimethylformamide, ketone solvents such as acetone and methyl ethyl ketone, ether solvents such as diethyl ether and tetrahydrofuran, toluene, chlorobenzene, 1 -Aromatic solvents such as chloronaphthalene are effective, and they are used in the range of 1 to 100 parts by mass, preferably 2 to 50 parts by mass with respect to 1 part by mass of the arylamine compound alcohol. It is good.
The reaction temperature is not particularly limited. After completion of the reaction, the reaction solution is poured into water, extracted with a solvent such as toluene, hexane, or ethyl acetate, washed with water, and further purified using an adsorbent such as activated carbon, silica gel, porous alumina, or activated clay if necessary. May be.

Specific chain-polymerizable charge transport materials (especially chain-polymerizable compounds represented by the general formula (II)) include, for example, the following general charge transport material synthesis methods (formylation, esterification, etherification, hydrogenation) ) And synthesized.
-Formylation: Aromatic compounds with electron donating groups-Heterocyclic compounds-Reactions suitable for introducing formyl groups into alkenes. In general, DMF and phosphorus oxytrichloride are used, and the reaction temperature is often from room temperature (for example, 25 ° C.) to about 100 ° C.
Esterification: A condensation reaction between an organic acid and a compound containing a hydroxyl group such as alcohol or phenol. It is preferable to use a method of biasing the equilibrium toward the ester side by coexisting a dehydrating agent or removing water out of the system.
Etherification: A Williamson synthesis method in which an alkoxide and an organic halogen compound are condensed is common.
-Hydrogenation: A method in which hydrogen is reacted with an unsaturated bond using various catalysts.

  In addition to the specific chain-polymerizable charge transport material, the reactive charge transport material may be a compound described in [0110] to [0153] of JP2012-163693A, [0055] of Japanese Patent No. 4365960. ] To [0082], the compounds described in Japanese Patent No. 4429340, [0040] to [0043], the compounds described in JP 2013-195762 [0161] to [0166], and the like. Can be mentioned.

The content of the reactive charge transport material is not used in combination with the reactive material described later, and when two or more reactive charge transport materials are used, for example, the total solid content in the composition for layer formation 40 mass% or more and 95 mass% or less is good, Preferably it is 50 mass% or more and 95 mass% or less.
On the other hand, the content of the reactive charge transport material is, for example, 50% by mass or more and 95% by mass or less with respect to the total solid content in the composition for layer formation when used in combination with the reactive material described later. Preferably they are 60 mass% or more and 95 mass% or less.

-Reactive material-
The reactive material is a reactive compound that does not have a charge transporting skeleton in the same molecule and has at least a reactive group. In particular, the reactive material is preferably a chain-polymerizable compound having at least a chain-polymerizable functional group without having a charge-transporting skeleton in the same molecule from the viewpoint of suppressing unevenness in image density.
Here, examples of the chain polymerizable group include the groups described in the reactive charge transport material. In addition, examples of the reactive group other than the chain polymerizable group include the groups described in the reactive charge transport material.

  The chain polymerizable material may be any of a monomer, an oligomer and a polymer. Specific examples of the chain polymerizable material include a (meth) acrylic acid ester compound and an aromatic compound having a vinyl group from the viewpoint of suppressing density unevenness of an image.

  The (meth) acrylic acid ester compound may be a monofunctional compound having one (meth) acryloyl group or a polyfunctional compound having two or more (meth) acryloyl groups. A compound or a bifunctional compound is preferable, and a monofunctional compound is more preferable.

The monofunctional (meth) acrylic acid ester compound includes a monofunctional unsubstituted alkyl (meth) acrylate having an unsubstituted alkyl group, a substituted alkyl group in which some or all of the hydrogen atoms are substituted with a substituent. And substituted alkyl (meth) acrylates.
The number of carbon atoms of the alkyl group of the monofunctional alkyl (meth) acrylate is preferably 10 or more and 20 or less, and more preferably 15 or more and 18 or less, from the viewpoint of suppressing density unevenness in the image. The alkyl group may be linear, branched or cyclic, but is preferably linear or branched, and more preferably linear, from the viewpoint of suppressing density unevenness in the image.
Examples of the substituent that substitutes the alkyl group include a halogen atom, a hydroxyl group, an alkoxy group, and an aryl group (for example, a phenyl group).

The monofunctional (meth) acrylic acid ester compound includes an unsubstituted alkyl (meth) acrylate and a fluorinated alkyl group in which some or all of the hydrogen atoms are substituted with fluorine atoms from the viewpoint of suppressing density unevenness in the image. Preferred are fluorinated alkyl (meth) acrylates having
The fluorinated alkyl (meth) acrylate, for _{example, -C n H 2n -C m F} m -C (R) is indicated by ₃ alkyl group (where, n is an integer of 1 to 20, m is 1 Represents an integer of 20 or less, and R represents a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 30 carbon atoms, wherein three symbols “R” bonded to the terminal “C” are the same atom or group. Or may be a different atom or group.) Fluorinated alkyl (meth) acrylates.

  Examples of the monofunctional unsubstituted alkyl (meth) acrylate include, for example, isobutyl (meth) acrylate, t-butyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isobornyl (meth) ) Acrylate, cyclohexyl (meth) acrylate and the like.

  Examples of monofunctional substituted (meth) acrylates include 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, phenoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxy Examples include propyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-decyltetradecanyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate.

  Among monofunctional substituted (meth) acrylates, examples of monofunctional fluorinated alkyl (meth) acrylates include trifluoromethyl (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 1, 1,1,3,3,3-hexafluoro-2-propyl (meth) acrylate, perfluoropropylmethyl (meth) acrylate, polyperfluorobutylmethyl (meth) acrylate, perfluoropentylmethyl (meth) acrylate, Fluorohexylmethyl (meth) acrylate, perfluoroheptylmethyl (meth) acrylate, perfluorooctylmethyl (meth) acrylate, perfluorononylmethyl (meth) acrylate, perfluorodecylmethyl (meth) acrylate, perfluoroundecyl Chill (meth) acrylate, perfluorododecylmethyl (meth) acrylate, perfluorotridecylmethyl (meth) acrylate, perfluorotetradecylmethyl (meth) acrylate, 2- (trifluoromethyl) ethyl (meth) acrylate, 2- (Perfluoroethyl) ethyl (meth) acrylate, 2- (perfluoropropyl) ethyl (meth) acrylate, 2- (perfluorobutyl) ethyl (meth) acrylate, 2- (perfluoropentyl) ethyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acrylate, 2- (perfluoroheptyl) ethyl (meth) acrylate, 2- (perfluorooctyl) ethyl (meth) acrylate, 2- (perfluorononyl) ethyl (meth) Acry Over DOO, perfluoro tridecyl (meth) acrylate, 2- (perfluoro-tetradecyl) ethyl (meth) acrylate.

Examples of the polyfunctional (meth) acrylic acid ester compound include various polyfunctional (meth) acrylates (for example, (meth) acrylates in which two or more (meth) acryloyl groups are linked to an alkyl chain).
Examples of the polyfunctional (meth) acrylate include 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate. Can be mentioned.

Examples of the polyfunctional (meth) acrylate include the following compounds.

Examples of the polyfunctional (meth) acrylic acid ester compound include polyfunctional fluorine-containing (meth) acrylates. Examples of the polyfunctional fluorine-containing (meth) acrylate include the following compounds.

  On the other hand, examples of the aromatic compound having a vinyl group include styrene (vinyl benzene), vinyl naphthalene, divinyl benzene, divinyl naphthalene, and diallyl phthalate.

In addition to the reactive materials (chain-polymerizable materials), the following monomers may also be mentioned. Monofunctional monomers include methoxytriethylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, and benzyl (meth). Acrylate, ethyl carbitol (meth) acrylate, methoxy polyethylene glycol (meth) acrylate, methoxy polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, hydroxyethyl o-phenylphenol (meta ) Acrylate, o-phenylphenol glycidyl ether (meth) acrylate, styrene and the like.

Examples of the bifunctional monomer include diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and the like.
Examples of the trifunctional monomer include trivinylcyclohexane.
Examples of the tetrafunctional monomer include ditrimethylolpropane tetra (meth) acrylate and aliphatic tetra (meth) acrylate.
Examples of the pentafunctional or higher functional monomer include dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate, as well as (meth) acrylate having a polyester skeleton, a urethane skeleton, and a phosphazene skeleton.

  Among reactive materials (chain polymerizable materials), examples of the polymer include, for example, JP-A-5-216249, JP-A-5-323630, JP-A-11-52603, and JP-A-2000-264961. And those disclosed in Japanese Patent Laid-Open No. 2005-2291.

  These reactive materials (chain polymerizable materials) may be used alone or in combination of two or more.

  The content of the reactive material (chain polymerizable material) is, for example, preferably from 5% by mass to 60% by mass, and preferably from 10% by mass to 55% by mass with respect to the total solid content in the composition for layer formation. It is 15 mass% or less, More preferably, it is 15 mass% or more and 50 mass% or less.

-Combination of two or more types of reactive charge transport materials, Combination of reactive charge transport materials and reactive materials-
Protected with a cured film of a composition containing two or more reactive charge transport materials from the viewpoint of satisfying the formula (B1), formula (B2), formula (C1) and formula (C2) and suppressing density unevenness of the image When constituting a layer (outermost surface layer), the following combinations are preferable.
・ Combination of a polyfunctional reactive charge transport material having a styryl group and a monofunctional reactive charge transport material having a styryl group ・ A monofunctional reactive charge transport material having a styryl group and a monofunctional compound having an acrylic group Combination with a reactive charge transporting material-Combination of a polyfunctional reactive charge transporting material having a styryl group and a polyfunctional reactive charge transporting material having a styryl group-Multifunctional reactive charge transporting material having a styryl group Of polyfunctional reactive charge transport materials with acrylic groups

On the other hand, the curing of the composition containing the reactive charge transporting material and the reactive material from the viewpoint of satisfying the formula (B1), the formula (B2), the formula (C1) and the formula (C2) and suppressing the density unevenness of the image. When the protective layer (outermost surface layer) is formed of a film, the following combinations are preferable.
・ A combination of a polyfunctional reactive charge transport material having a styryl group and a monofunctional fluorinated alkyl (meth) acrylate ・ A polyfunctional reactive charge transport material having a styryl group and a monofunctional unsubstituted (meth) acrylate -A combination of a polyfunctional reactive charge transport material having a styryl group and a polyfunctional fluorine-containing (meth) acrylate-A polyfunctional reactive charge transport material having a styryl group and a polyfunctional (meth) acrylate (For example, (meth) acrylates in which two or more (meth) acryloyl groups are linked to an alkyl chain)

-Resin particles-
The film constituting the protective layer (outermost surface layer) may contain resin particles.
Examples of the resin particles include polycarbonate resin particles such as bisphenol A type or bisphenol Z type, acrylic resin, methacrylic resin, polyarylate resin, polyester resin, polyvinyl chloride resin, polystyrene resin, acrylonitrile-styrene copolymer resin, Acrylonitrile-butadiene copolymer resin, polyvinyl acetate resin, polyvinyl formal resin, polysulfone resin, styrene-acrylic copolymer, styrene-butadiene copolymer resin, vinylidene chloride-acrylonitrile copolymer resin, vinyl chloride-vinyl acetate- Insulating resin particles such as maleic anhydride resin, silicone resin, phenol-formaldehyde resin, polyacrylamide resin, polyamide resin, chlorine rubber, and polyvinylcarbazole, poly Examples thereof include particles of an organic photoconductive polymer such as vinyl anthracene and polyvinyl pyrene.
These resin particles may be hollow particles.
The resin particles may be used alone or in combination of two or more.

The film constituting the protective layer (outermost surface layer) may contain fluorine-containing resin particles as resin particles.
Examples of the fluorine-containing resin particles include homopolymers of fluoroolefins and copolymers of two or more types, which are copolymers of one or more types of fluoroolefins and non-fluorinated monomers. .

  Examples of the fluoroolefin include perhaloolefin such as tetrafluoroethylene (TFE), perfluorovinyl ether, hexafluoropropylene (HFP), and chlorotrifluoroethylene (CTFE), vinylidene fluoride (VdF), trifluoroethylene, and fluoride. Non-perfluoroolefins such as vinyl can be mentioned, and VdF, TFE, CTFE, HFP and the like are preferable.

  On the other hand, examples of non-fluorine monomers include hydrocarbon olefins such as ethylene, propylene, and butene, alkyl vinyl ethers such as cyclohexyl vinyl ether (CHVE), ethyl vinyl ether (EVE), butyl vinyl ether, and methyl vinyl ether, and polyoxyethylene allyl ether. (POEAE), alkenyl vinyl ethers such as ethyl allyl ether, organosilicon compounds having a reactive α, β-unsaturated group such as vinyltrimethoxysilane (VSi), vinyltriethoxysilane, vinyltris (methoxyethoxy) silane, and acrylic acid Acrylic esters such as methyl and ethyl acrylate, methacrylates such as methyl methacrylate and ethyl methacrylate, vinyl acetate, vinyl benzoate, (Trade name, vinyl ester manufactured by Shell) and the like, and alkyl vinyl ethers, allyl vinyl ethers, vinyl esters, and organosilicon compounds having a reactive α, β-unsaturated group are preferred.

  Among these, those having a high fluorination rate are preferable, such as polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoro (alkyl vinyl ether) copolymer (PFA). ), Ethylene-tetrafluoroethylene copolymer (ETFE), ethylene-chlorotrifluoroethylene copolymer (ECTFE), and the like are preferable. Among these, PTFE, FEP, and PFA are particularly preferable.

As the fluorine-containing resin particles, for example, particles (fluorine resin aqueous dispersion) produced by a method such as emulsion polymerization of a fluorine-based monomer may be used as they are, or may be used after thoroughly washing with water and drying. Good.
The average particle size of the fluorine-containing resin particles is preferably 0.01 μm or more and 100 μm or less, and particularly preferably 0.03 μm or more and 5 μm or less.
In addition, the average particle diameter of the said fluorine-containing resin particle means the value measured using laser diffraction type particle size distribution measuring device LA-700 (made by Horiba Seisakusho).

  As the fluorine-containing resin particles, commercially available ones may be used. For example, as PTFE particles, Fullon L173JE (Asahi Glass Co., Ltd.), Taniion THV-221AZ, Taniion 9205 (Sumitomo 3M), Lubron L2, Lubron And L5 (manufactured by Daikin).

  The fluorine-containing resin particles may be irradiated with laser light having an oscillation wavelength in the ultraviolet region. The laser beam irradiated to the fluorine-containing resin particles is not particularly limited, and examples thereof include an excimer laser. As the excimer laser light, an ultraviolet laser light having a wavelength of 400 nm or less, particularly 193 nm or more and 308 nm or less is suitable. In particular, KrF excimer laser light (wavelength: 248 nm) and ArF excimer laser light (wavelength: 193 nm) are preferred. Excimer laser light irradiation is usually performed in the air at room temperature (25 ° C.), but may be performed in an oxygen atmosphere.

The irradiation conditions of excimer laser light depend on the type of fluororesin and the required degree of surface modification, but general irradiation conditions are as follows.
Fluence: 50 mJ / cm ² / pulse or more Incident energy: 0.1 J / cm ² or more Shot number: 100 or less

Particularly suitable irradiation conditions for particularly suitable KrF excimer laser light and ArF excimer laser light are as follows.
KrF
Fluence: 100 mJ / cm ² / pulse or more 500 mJ / cm ² / pulse or less incident energy: 0.2 J / cm ² or more 2.0 J / cm ² or less number of shots: 1 to 20

ArF
Fluence: 50 mJ / cm ² / pulse or more 150 mJ / cm ² / pulse or less incident energy: 0.1 J / cm ² or more 1.0 J / cm ² or less number of shots: 1 to 20

  The content of the fluorine-containing resin particles is preferably 1% by mass or more and 20% by mass or less, and more preferably 1% by mass or more and 12% by mass or less with respect to the total solid content of the protective layer (outermost surface layer).

-Fluorine-containing dispersant-
The film constituting the protective layer (outermost surface layer) may contain a fluorine-containing dispersant together with the fluorine-containing resin particles.
Since the fluorine-containing dispersant is used to disperse the fluorine-containing resin particles in the protective layer (outermost surface layer), it preferably has a surface active action, that is, has a hydrophilic group in the molecule. A substance having a hydrophobic group is preferable.

Examples of the fluorine-containing dispersant include resins obtained by polymerizing the following reactive monomers (hereinafter referred to as “specific resins”). Specifically, a random or block copolymer of an acrylate having a perfluoroalkyl group and a monomer having no fluorine, a methacrylate homopolymer, and an acrylate having the perfluoroalkyl group, and not having the fluorine Examples thereof include random or block copolymers of monomers and random or block copolymers of methacrylate and monomers not containing fluorine. Examples of the acrylate having a perfluoroalkyl group include 2,2,2-trifluoroethyl methacrylate and 2,2,3,3,3-pentafluoropropyl methacrylate.
Moreover, as a monomer which does not have fluorine, for example, isobutyl acrylate, t-butyl acrylate, isooctyl acrylate, lauryl acrylate, stearyl acrylate, isobornyl acrylate, cyclohexyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate 2-ethoxyethyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate, ethyl carbitol acrylate, phenoxyethyl acrylate, 2-hydroxy acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, methoxypolyethylene glycol acrylate, methoxypolyethylene glycol methacrylate Phenoxypolyethyleneglycol Le acrylate, phenoxy polyethylene glycol methacrylate, hydroxyethyl o- phenylphenol acrylate, o- phenylphenol glycidyl ether acrylate. Also, block or branch polymers disclosed in US Pat. No. 5,637,142 and Patent No. 4,251,662 can be used. In addition, a fluorine-type surfactant is mentioned. Specific examples of the fluorosurfactant include Surflon S-611, Surflon S-385 (manufactured by AGC Seimi Chemical Co., Ltd.), Aftergent 730FL, Aftergent 750FL (manufactured by Neos), PF-636, and PF-6520 (Kitamura). Chemical Co., Ltd.), Megafac EXP, TF-1507, Megafac EXP, TF-1535 (manufactured by DIC), FC-4430, FC-4432 (manufactured by 3M), and the like.
The weight average molecular weight of the specific resin is preferably 100 or more and 50000 or less.

  The content of the fluorine-containing dispersant is preferably 0.1% by mass or more and 1% by mass or less, and more preferably 0.2% by mass or more and 0.5% by mass or less with respect to the total solid content of the protective layer (outermost surface layer). preferable.

  As a method of attaching the fluorine-containing dispersant to the surface of the fluorine-containing resin particles, the fluorine-containing dispersant may be attached directly to the surface of the fluorine-containing resin particles, or first, the above monomer is added to the fluorine-containing resin particles. The specific resin may be formed on the surface of the fluorine-containing resin particles by polymerizing after adsorbing on the surface.

  The fluorine-containing dispersant may be used in combination with other surfactants. However, the amount is preferably as small as possible, and the content of the other surfactant is preferably 0 part by mass or more and 0.1 part by mass or less, preferably 0 part by mass with respect to 1 part by mass of the fluorine-containing resin particles. It is 0.05 parts by mass or less, more preferably 0 parts by mass or more and 0.03 parts by mass or less.

Other surfactants are preferably nonionic surfactants, such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl esters, sorbitan alkyl esters, polyoxyethylene sorbitan alkyls. Examples thereof include esters, glycerin esters, fluorosurfactants and derivatives thereof.
Specific examples of polyoxyethylenes include, for example, Emulgen 707 (manufactured by Kao Corporation), NAROACTY CL-70, NAROACTY CL-85 (manufactured by Sanyo Chemical Industries), Leocor TD-120 (manufactured by Lion Corporation), and the like. It is done.

-Non-reactive charge transport material-
The film constituting the protective layer (outermost surface layer) may be used in combination with a non-reactive charge transport material. Since the non-reactive charge transport material does not have a reactive group, the concentration of the charge transport component increases when the non-reactive charge transport material is used for the protective layer (outermost surface layer), and the electrical characteristics are improved. It is effective for further improvement. Further, a non-reactive charge transport material may be added to reduce the crosslink density and adjust the strength.

As the non-reactive charge transport material, a known charge transport material may be used. Specifically, triarylamine compounds, benzidine compounds, arylalkane compounds, aryl-substituted ethylene compounds, stilbene compounds. Anthracene compounds, hydrazone compounds and the like are used.
Among these, those having a triphenylamine skeleton are preferable from the viewpoint of charge mobility and compatibility.

  The non-reactive charge transport material is preferably used in an amount of 0% by mass to 30% by mass, more preferably 1% by mass to 25% by mass with respect to the total solid content in the coating liquid for layer formation. More preferably, it is 5 mass% or more and 25 mass% or less.

-Other additives-
The film constituting the protective layer (outermost surface layer) is further mixed with other coupling agents, especially fluorine-containing coupling agents, for the purpose of adjusting the film formability, flexibility, lubricity, and adhesion. May be used. As such a compound, various silane coupling agents and commercially available silicone hard coat agents are used. Moreover, you may use the silicon compound and fluorine-containing compound which have a radically polymerizable group.

As silane coupling agents, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyltrimethoxy Silane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, N-2 (aminoethyl) -3-aminopropyltriethoxysilane, tetramethoxysilane, methyltrimethoxysilane , Dimethyldimethoxysilane, and the like.
As commercially available hard coat agents, KP-85, X-40-9740, X-8239 (above, manufactured by Shin-Etsu Chemical Co., Ltd.), AY42-440, AY42-441, AY49-208 (above, made by Toray Dow Corning) ) And the like.

  In order to impart water repellency and the like, (tridecafluoro-1,1,2,2-tetrahydrooctyl) triethoxysilane, (3,3,3-trifluoropropyl) trimethoxysilane, 3- (hepta) Fluoroisopropoxy) propyltriethoxysilane, 1H, 1H, 2H, 2H-perfluoroalkyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorooctyl Fluorine-containing compounds such as triethoxysilane may be added.

Although the silane coupling agent is used in an arbitrary amount, the amount of the fluorine-containing compound may be 0.25 times or less by mass with respect to the compound containing no fluorine from the viewpoint of the film formability of the crosslinked film. preferable. Furthermore, you may mix the reactive fluorine compound etc. which are disclosed by Unexamined-Japanese-Patent No. 2001-166510 etc.
Examples of the silicon compound and the fluorine-containing compound having a radical polymerizable group include compounds described in JP-A No. 2007-11005.

It is preferable to add a deterioration inhibitor to the film constituting the protective layer (outermost surface layer). As the deterioration inhibitor, hindered phenols or hindered amines are preferable, organic sulfur antioxidants, phosphite antioxidants, dithiocarbamate antioxidants, thiourea antioxidants, benzimidazole antioxidants. You may use well-known antioxidants, such as an agent.
The addition amount of the deterioration inhibitor is preferably 20% by mass or less, and more preferably 10% by mass or less.

Examples of the hindered phenol antioxidant include Irganox 1076, Irganox 1010, Irganox 1098, Irganox 245, Irganox 1330, Irganox 3114, Irganox 1076 (manufactured by Ciba Japan), 3, 5 -Di-t-butyl-4-hydroxybiphenyl and the like.
Examples of the hindered amine antioxidant include Sanol LS2626, Sanol LS765, Sanol LS770, Sanol LS744 (Sanyo Lifetech Co., Ltd.), Tinuvin 144, Tinuvin 622LD (above, manufactured by Ciba Japan), Mark LA57, Mark LA67, Mark LA62, Mark LA68, Mark LA63 (manufactured by Adeka Co., Ltd.), and thioethers include Sumilizer TPS and Sumitizer TP-D (manufactured by Sumitomo Chemical Co., Ltd.), and phosphites include Mark 2112, Mark PEP-8, Mark PEP-24G, Mark PEP-36, Mark 329K, Mark HP-10 (manufactured by Adeka) and the like.

Conductive particles, organic or inorganic particles may be added to the film constituting the protective layer (outermost surface layer).
An example of such particles is silicon-containing particles. The silicon-containing particles are particles containing silicon as a constituent element, and specific examples include colloidal silica and silicone particles. The colloidal silica used as the silicon-containing particles is preferably silica having an average particle diameter of 1 nm to 100 nm, more preferably 10 nm to 30 nm, in an acidic or alkaline aqueous dispersion, or an organic solvent such as alcohol, ketone, or ester. It is selected from those dispersed in. As the particles, commercially available particles may be used.

  The solid content of colloidal silica in the protective layer is not particularly limited, but is 0.1% by mass or more and 50% by mass or less, preferably 0.1% by mass based on the total solid content of the protective layer. % Or more and 30% by mass or less.

The silicone particles used as the silicon-containing particles may be selected from silicone resin particles, silicone rubber particles, and silicone surface-treated silica particles, and commercially available particles may be used.
These silicone particles are spherical, and the average particle diameter is preferably 1 nm to 500 nm, more preferably 10 nm to 100 nm.
The content of the silicone particles in the surface layer is preferably 0.1% by mass or more and 30% by mass or less, more preferably 0.5% by mass or more and 10% by mass or less, based on the total solid content of the protective layer. .

Other particles include ZnO—Al ₂ O ₃ , SnO ₂ —Sb ₂ O ₃ , In ₂ O ₃ —SnO ₂ , ZnO ₂ —TiO ₂ , ZnO—TiO ₂ , MgO—Al ₂ O ₃ , FeO. Examples thereof include semiconductive metal oxides such as —TiO ₂ , TiO ₂ , SnO ₂ , In ₂ O ₃ , ZnO, and MgO. Furthermore, various known dispersing materials may be used to disperse the particles.

Oil such as silicone oil may be added to the film constituting the protective layer (outermost surface layer).
Silicone oils include silicone oils such as dimethylpolysiloxane, diphenylpolysiloxane, and phenylmethylsiloxane; amino-modified polysiloxane, epoxy-modified polysiloxane, carboxyl-modified polysiloxane, carbinol-modified polysiloxane, methacryl-modified polysiloxane, mercapto-modified poly Reactive silicone oils such as siloxane and phenol-modified polysiloxane; cyclic dimethylcyclosiloxanes such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane and dodecamethylcyclohexasiloxane; 1,3,5- Trimethyl-1.3.5-triphenylcyclotrisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetraphenylcyclo Cyclic methylphenylcyclosiloxanes such as trasiloxane, 1,3,5,7,9-pentamethyl-1,3,5,7,9-pentaphenylcyclopentasiloxane; cyclic phenylcyclosiloxanes such as hexaphenylcyclotrisiloxane Fluorine-containing cyclosiloxanes such as 3- (3,3,3-trifluoropropyl) methylcyclotrisiloxane; Hydrosilyl group-containing cyclosiloxanes such as methylhydrosiloxane mixture, pentamethylcyclopentasiloxane, and phenylhydrocyclosiloxane And vinyl group-containing cyclosiloxanes such as pentavinylpentamethylcyclopentasiloxane.

  In order to improve the wettability of the coating film, a silicone-containing oligomer, a fluorine-containing acrylic polymer, a silicone-containing polymer, or the like may be added to the film constituting the protective layer (outermost surface layer).

Metal, metal oxide, carbon black, or the like may be added to the film constituting the protective layer (outermost surface layer). Examples of the metal include aluminum, zinc, copper, chromium, nickel, silver, and stainless steel, or those obtained by depositing these metals on the surface of resin particles. Examples of the metal oxide include zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, tin-doped indium oxide, antimony and tantalum-doped tin oxide, and antimony-doped zirconium oxide. .
These are used alone or in combination of two or more. When two or more types are used in combination, they may be simply mixed or mixed by solid solution or fusion. The average particle size of the conductive particles is preferably 0.3 μm or less, particularly preferably 0.1 μm or less.

-Composition-
The composition used to form the protective layer is preferably prepared as a protective layer-forming coating solution obtained by dissolving or dispersing each component in a solvent.
Here, the solvent of the coating solution for forming the protective layer is charge transport from the viewpoint of suppressing the solubility of the charge transport material, the dispersibility of the fluorine-containing resin particles, and the uneven distribution of the fluorine-containing resin particles on the surface layer side of the outermost surface layer. The difference (absolute value) in SP value (solubility parameter calculated by the Feders method) with the binder resin (specific polycarbonate copolymer) of the layer is 2.0 or more and 4.0 or less (preferably 2.5 or more and 3.5 The following ketone solvents or ester solvents are preferably used.
Specifically, as a solvent for the coating solution for forming the protective layer, for example, methyl ethyl ketone, methyl isobutyl ketone, diisopropyl ketone, diisobutyl ketone, ethyl n butyl ketone, di n propyl ketone, methyl n amyl ketone, methyl n butyl ketone, diethyl ketone, Ketones such as methyl n-propyl ketone; isopropyl acetate, isobutyl acetate, ethyl acetate, npropyl acetate, nbutyl acetate, ethyl isovalerate, isoamyl acetate, isopropyl butyrate, isoamyl propionate, butyl butyrate, amyl acetate, butyl propionate And single solvents or mixed solvents such as esters such as ethyl propionate, methyl acetate, methyl propionate, and allyl acetate. Also, 0% by mass or more and 50% by mass or less of an ether solvent (for example, diethyl ether, dioxane, diisopropyl ether, cyclopentyl methyl ether, tetrahydrofuran, etc.), an alkylene glycol solvent (for example, 1-methoxy-2-propanol, 1-ethoxy- 2-propanol, ethylene glycol monoisopropyl ether, propylene glycol monomethyl ether acetate, etc.) may be mixed and used.

  As a dispersion method for dispersing the fluorine-containing resin particles in the coating liquid for forming the protective layer, a media dispersion machine such as a ball mill, a vibration ball mill, an attritor, a sand mill, a horizontal sand mill, a stirring, an ultrasonic dispersion machine, a roll mill, Examples thereof include a dispersion method using a medialess disperser such as a high-pressure homogenizer. Furthermore, as the dispersion method, as a high-pressure homogenizer, a collision method in which the dispersion liquid is dispersed by liquid-liquid collision or liquid wall collision in a high-pressure state, a penetration method in which a fine flow path is dispersed in a high-pressure state, etc. A dispersion method is also mentioned.

  The method for preparing the coating liquid for forming the protective layer is not particularly limited, and the charge transport material, the fluorine-containing resin particles, the fluorine-containing dispersant and, if necessary, other components such as a solvent are mixed, You may prepare using the above-mentioned disperser, or two liquids of the liquid mixture A containing a fluorine-containing resin particle, a fluorine-containing dispersing agent, and a solvent, and the liquid mixture B containing at least a charge transport material and a solvent are separately prepared. You may prepare by mixing these liquid mixture A and liquid mixture B after preparing. By mixing the fluorine-containing resin particles and the fluorine-containing dispersant in a solvent, the fluorine-containing dispersant is easily attached to the surface of the fluorine-containing resin particles.

  In addition, when a coating liquid for forming a protective layer is obtained by reacting the above-mentioned components, each component may be simply mixed and dissolved, but is preferably room temperature (20 ° C.) or higher and 100 ° C. or lower, more preferably 30 ° C. Heating is performed at 80 ° C. or lower, preferably 10 minutes or longer and 100 hours or shorter, more preferably 1 hour or longer and 50 hours or shorter. In this case, it is also preferable to irradiate ultrasonic waves.

-Formation of protective layer-
The coating solution for forming the protective layer is formed on the surface to be coated (charge transport layer) by a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, a curtain coating method, The coating is performed by a normal method such as an inkjet coating method.
Thereafter, light, electron beam or heat is applied to the obtained coating film to cause radical polymerization, thereby curing the coating film.

  As the curing method, heat, light, radiation or the like is used. When curing with heat and light, a polymerization initiator is not necessarily required, but a photocuring catalyst or a thermal polymerization initiator may be used. Known photocuring catalysts and thermal polymerization initiators are used as the photocuring catalyst and the thermal polymerization initiator. The radiation is preferably an electron beam.

-Electron beam curing When an electron beam is used, the acceleration voltage is preferably 300 KV or less, and optimally 150 KV or less. The dose is preferably in the range of 1 Mrad to 100 Mrad, more preferably in the range of 3 Mrad to 50 Mrad. When the acceleration voltage is 300 KV or less, damage caused by electron beam irradiation on the characteristics of the photoreceptor is suppressed. Further, when the dose is 1 Mrad or more, crosslinking is sufficiently performed, and when the dose is 100 Mrad or less, deterioration of the photoreceptor is suppressed.

  Irradiation is performed in an inert gas atmosphere such as nitrogen or argon at an oxygen concentration of 1000 ppm, preferably 500 ppm or less, and may be further heated to 50 ° C. or higher and 150 ° C. or lower during or after irradiation.

-Photocuring As a light source, a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, etc. are used, A suitable wavelength may be selected using filters, such as a band pass filter. Irradiation time, the light intensity is selected freely, for example, the illuminance (365 nm) is 300 mW / cm ² or more, preferably 1000 mW / cm ² or less, for example, the case of irradiation with UV light of 600 mW / cm ^2, 5 seconds or more 360 What is necessary is just to irradiate for less than a second.

  Irradiation is performed under an inert gas atmosphere such as nitrogen or argon, preferably at an oxygen concentration of 1000 ppm or less, more preferably 500 ppm or less, and may be further heated to 50 ° C. or more and 150 ° C. or less during or after the irradiation.

Examples of the photocuring catalyst include intramolecular cleavage types such as benzyl ketal, alkylphenone, aminoalkylphenone, phosphine oxide, titanocene, and oxime.
More specifically, examples of the benzyl ketal system include 2,2-dimethoxy-1,2-diphenylethane-1-one.

Examples of the alkylphenone series include 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl]. 2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl- Examples include propan-1-one, acetophenone, and 2-phenyl-2- (p-toluenesulfonyloxy) acetophenone.
Examples of aminoalkylphenones include p-dimethylaminoacetophenone, p-dimethylaminopropiophenone, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2-benzyl-2- Dimethylamino-1- (4-morpholinophenyl) -butanone-1,2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1 -Butanone and the like.
Examples of the phosphinoxide include 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide.
Examples of the titanocene include bis (η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium.
Examples of oxime compounds include 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], ethanone, 1- [9-ethyl-6- (2-methylbenzoyl)- 9H-carbazol-3-yl]-, 1- (O-acetyloxime) and the like.

Examples of the hydrogen abstraction type include benzophenone series, thioxanthone series, benzyl series, and Michler ketone series.
More specifically, examples of the benzophenone series include 2-benzoylbenzoic acid, 2-chlorobenzophenone, 4,4′-dichlorobenzophenone, 4-benzoyl-4′-methyldiphenyl sulfide, p, p′-bisdiethylaminobenzophenone, and the like. Can be mentioned.
Examples of the thioxanthone series include 2,4-diethylthioxanthen-9-one, 2-chlorothioxanthone, and 2-isopropylthioxanthone.
Examples of the benzyl type include benzyl, (±) -camphorquinone, p-anisyl and the like.

  These photopolymerization initiators are used alone or in combination of two or more.

-Thermosetting Thermal polymerization initiators include thermal radical generators or derivatives thereof. Specifically, for example, V-30, V-40, V-59, V601, V65, V-70, VF- Azo initiators such as 096, VE-073, Vam-110, Vam-111 (manufactured by Wako Pure Chemical Industries, Ltd.), OTazo-15, OTazo-30, AIBN, AMBN, ADVN, ACVA (Otsuka Chemical); Perhexa HC, Perhexa C, Perhexa V, Perhexa 22, Perhexa MC, Perbutyl H, Parkmill H, Parkmill P, Permenta H, Perocta H, Perbutyl C, Perbutyl D, Perhexyl D, Parroyl IB, Parroyl 355, Parroyl L, Parroyl SA , Nyper BW, Nyper BMT-K40 / M, Parroyl IPP, Parro Il NPP, Parroyl TCP, Parroyl OPP, Parroyl SBP, Park Mill ND, Perocta ND, Perhexyl ND, Perbutyl ND, Perbutyl NHP, Perhexyl PV, Perbutyl PV, Perhexa 250, Perocta O, Perhexyl O, Perbutyl O, Perbutyl L, Perbutyl 355 Perhexyl I, perbutyl I, perbutyl E, perhexa 25Z, perbutyl A, perhexyl Z, perbutyl ZT, perbutyl Z (manufactured by NOF Chemical), Kayaketal AM-C55, Trigonox 36-C75, Laurox, Perkadox L-W75, Parkadox CH-50L, Trigonox TMBH, Kayacumen H, Kayabutyl H-70, Percadox BC-FF, Kaya Hexa AD, Parkadox 14, Kayabuchi C, Kayabutyl D, Kayahexa YD-E85, Parkadox 12-XL25, Parkadox 12-EB20, Trigonox 22-N70, Trigonox 22-70E, Trigonox D-T50, Trigonox 423-C70, Kayaester CND-C70, Kayaester CND-W50, Trigonox 23-C70, Trigonox 23-W50N, Trigonox 257-C70, Kaya ester P-70, Kaya ester TMPO-70, Trigonox 121, Kaya ester O, Kaya ester HTP-65W, Kaya ester AN, Trigonox 42 , Trigonox F-C50, Kaya Butyl B, Kaya Carbon EH-C70, Kaya Carbon EH-W60, Kaya Carbon I-20, Kaya Carbon BIC-75, Trigonok 117, Kayalen 6-70 (manufactured by Kayaku Akzo), Lupelox 610, Lupelox 188, Lupelox 844, Lupelox 259, Lupelox 10, Lupelox 701, Lupelox 11, Lupelox 26, Lupelox 80, Lupelox 7, Lupelox P, Lupelox P, Lupelox 546, Lupelox 554, Lupelox 575, Lupelox TANPO, Lupelox 555, Lupelox 570, Lupelox TAP, Lupelox TBIC, Lupelox TBEC, Lupelox JW, Lupelox TAIC, Lupelox DC, Lupelox DC, Lupelox DC , Lupelox 220, Lupelox 230, Lupelox 23 3, Lupelox 531 (manufactured by Arkema Yoshitomi) and the like.

  Among these, when an azo polymerization initiator having a molecular weight of 250 or more is used, the reaction proceeds without unevenness at a low temperature, so that a high-strength film with suppressed unevenness can be formed. More preferably, the molecular weight of the azo polymerization initiator is 250 or more, and more preferably 300 or more.

  The heating is performed under an inert gas atmosphere such as nitrogen or argon, and the oxygen concentration is preferably 1000 ppm or less, more preferably 500 ppm or less, preferably 50 ° C. or more and 170 ° C. or less, more preferably 70 ° C. or more and 150 ° C. or less. Preferably it is 10 minutes or more and 120 minutes or less, More preferably, 15 minutes or more and 100 minutes or less are heated.

  The total content of the photocuring catalyst or the thermal polymerization initiator is preferably 0.1% by mass or more and 10% by mass or less, more preferably 0.1% by mass or more, based on the total solid content in the solution for forming the layer. 8 mass% or less is more preferable, and the range of 0.1 mass% or more and 5 mass% or less is especially preferable.

In this embodiment, if the reaction proceeds too quickly, the structure of the coating film is difficult to be relaxed by crosslinking, and the generation of radicals is relatively slow because it tends to cause film unevenness and wrinkles. The curing method is adopted.
In particular, by combining a specific chain polymerizable charge transport material and curing by heat, the structure relaxation of the coating film is promoted, and a high protective layer (outermost surface layer) excellent in surface properties is easily obtained.

  The thickness of the protective layer is, for example, preferably set in the range of 3 μm to 40 μm, more preferably 5 μm to 35 μm, and still more preferably 7 μm to 30 μm.

  The structure of each layer in the function-separated type photosensitive layer has been described with reference to the electrophotographic photoreceptor shown in FIG. 1, but this structure is also applied to each layer in the function-separated type electrophotographic photoreceptor shown in FIG. Can be adopted. Further, in the case of the single-layer type photosensitive layer of the electrophotographic photosensitive member shown in FIG.

That is, the single-layer type photosensitive layer (charge generation / charge transport layer) includes a charge generation material, a charge transport material, and, if necessary, a binder resin and other known additives. Is good. These materials are the same as those described in the charge generation material and the charge transport layer.
In the single-layer type photosensitive layer, the content of the charge generating material is preferably 10% by mass or more and 85% by mass or less, and preferably 20% by mass or more and 50% by mass or less with respect to the total solid content. In the single-layer type photosensitive layer, the content of the charge transport material is preferably 5% by mass or more and 50% by mass or less based on the total solid content.
The method for forming the single-layer type photosensitive layer is the same as the method for forming the charge generation layer and the charge transport layer.
The film thickness of the single-layer type photosensitive layer is, for example, from 5 μm to 50 μm, and preferably from 10 μm to 40 μm.

In the electrophotographic photosensitive member according to the present embodiment, the mode in which the outermost surface layer is the protective layer has been described, but a layer configuration without the protective layer may be employed.
In the case of a layer structure without a protective layer, in the electrophotographic photoreceptor shown in FIG. 1, the charge transport layer located on the outermost surface in the layer structure becomes the outermost surface layer. And the electric charge transport layer used as the said outermost surface layer is comprised with the cured film of the said specific composition.
In the case of a layer structure without a protective layer, in the electrophotographic photoreceptor shown in FIG. 3, the single-layer type photosensitive layer located on the outermost surface in the layer structure is the outermost surface layer. And the single layer type photosensitive layer used as the said outermost surface layer is comprised with the cured film of the said specific composition. However, a charge generating material is blended in the composition.

-Charging device-
As the charging device 8, a charging device that is disposed in contact with or close to the surface of the electrophotographic photosensitive member 7 and charges the surface of the electrophotographic photosensitive member is employed. Here, the arrangement of the charging device 8 in the vicinity means, for example, that the charging device 8 (the conductive member (charging member)) is arranged away from the surface of the electrophotographic photosensitive member 7 in a range of 1 μm to 200 μm. It shows that.
Specifically, as the charging device 8, a contact type charger in which a conductive or semiconductive member such as a charging roller, a charging brush, a charging film, a charging rubber blade, a charging tube or the like is brought into contact with the surface of the electrophotographic photosensitive member 7. A proximity charger in which the conductive or semiconductive member is provided separately from the surface of the electrophotographic photosensitive member 7 can be used.

-Exposure device-
Examples of the exposure device 9 include optical system devices that expose the surface of the electrophotographic photoreceptor 7 with light such as semiconductor laser light, LED light, and liquid crystal shutter light in a predetermined image-like manner. The wavelength of the light source is set within the spectral sensitivity region of the electrophotographic photosensitive member. As the wavelength of the semiconductor laser, near infrared having an oscillation wavelength near 780 nm is the mainstream. However, the present invention is not limited to this wavelength, and an oscillation wavelength laser in the 600 nm range or a laser having an oscillation wavelength of 400 nm to 450 nm as a blue laser may be used. In addition, a surface-emitting type laser light source that can output a multi-beam is also effective for color image formation.

-Developer-
Examples of the developing device 11 include a general developing device that performs development by bringing a developer into contact or non-contact with the developer. The developing device 11 is not particularly limited as long as it has the functions described above, and is selected according to the purpose. For example, a known developing device having a function of attaching a one-component developer or a two-component developer to the electrophotographic photosensitive member 7 using a brush, a roller, or the like can be used. Among these, those using a developing roller holding the developer on the surface are preferable.

  Here, the developer accommodated in the developing device includes toner particles and fatty acid metal salt particles. The fatty acid metal salt particles are included in the developer as an external additive.

Next, the configuration of the toner particles will be described.
The toner particles include, for example, a binder resin. The toner particles may contain a colorant, a release agent, and other additives as necessary.

-Binder resin Examples of the binder resin include styrenes (eg, styrene, parachlorostyrene, α-methylstyrene, etc.), (meth) acrylic acid esters (eg, methyl acrylate, ethyl acrylate, acrylic acid n-). Propyl, n-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, etc.), ethylenically unsaturated nitriles (Eg acrylonitrile, methacrylonitrile, etc.), vinyl ethers (eg vinyl methyl ether, vinyl isobutyl ether etc.), vinyl ketones (vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone etc.), olefins (eg ethyl , Propylene, a homopolymer of a monomer such as butadiene) and the like, or a vinyl-based resin composed of these monomers with two or more combinations copolymer.
As the binder resin, for example, epoxy resin, polyester resin, polyurethane resin, polyamide resin, cellulose resin, polyether resin, non-vinyl resin such as modified rosin, a mixture of these with the vinyl resin, or these Examples also include a graft polymer obtained by polymerizing a vinyl monomer in the coexistence.
These binder resins may be used alone or in combination of two or more.

  The content of the binder resin is, for example, preferably 40% by weight to 95% by weight, more preferably 50% by weight to 90% by weight, and more preferably 60% by weight to 85% by weight with respect to the entire toner particles. Further preferred.

Colorants Examples of the colorant include carbon black, chrome yellow, hansa yellow, benzidine yellow, sren yellow, quinoline yellow, pigment yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, permanent red, and brilliant carmine. 3B, Brilliant Carmine 6B, Dupont Oil Red, Pyrazolone Red, Resol Red, Rhodamine B Lake, Lake Red C, Pigment Red, Rose Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Pigment Blue, Various pigments such as phthalocyanine green and malachite green oxalate, or acridine series, xanthate , Azo, benzoquinone, azine, anthraquinone, thioindico, dioxazine, thiazine, azomethine, indico, phthalocyanine, aniline black, polymethine, triphenylmethane, diphenylmethane, thiazole And various dyes.
A colorant may be used individually by 1 type and may use 2 or more types together.

  As the colorant, a surface-treated colorant may be used as necessary, or it may be used in combination with a dispersant. A plurality of colorants may be used in combination.

  The content of the colorant is, for example, preferably 1% by mass or more and 30% by mass or less, and more preferably 3% by mass or more and 15% by mass or less with respect to the entire toner particles.

-Release agent Examples of release agents include hydrocarbon waxes; natural waxes such as carnauba wax, rice wax and candelilla wax; synthetic or mineral / petroleum waxes such as montan wax; fatty acid esters, montanate esters, etc. And ester waxes. The release agent is not limited to this.

The melting temperature of the release agent is preferably 50 ° C. or higher and 110 ° C. or lower, and more preferably 60 ° C. or higher and 100 ° C. or lower.
The melting temperature is determined from the DSC curve obtained by differential scanning calorimetry (DSC) according to the “melting peak temperature” described in JIS K-1987 “Method for measuring the transition temperature of plastics”.

  The content of the release agent is, for example, preferably 1% by mass to 20% by mass and more preferably 5% by mass to 15% by mass with respect to the entire toner particles.

Other additives Examples of the other additives include well-known additives such as magnetic materials, charge control agents, and inorganic powders. These additives are contained in the toner particles as internal additives.

Toner particle characteristics, etc. The toner particles may be toner particles having a single layer structure, or a so-called core-shell comprising a core (core particle) and a coating layer (shell layer) covering the core. It may be toner particles having a structure.
Here, the core / shell structure toner particles include, for example, a core portion including a binder resin and, if necessary, other additives such as a colorant and a release agent, and a binder resin. It is good to be comprised with the comprised coating layer.

  The volume average particle diameter (D50v) of the toner particles is preferably 2 μm or more and 10 μm or less, more preferably 3.0 μm or more and 5.8 μm or less, and more preferably 3.0 μm or more and 3.7 μm or less from the viewpoint of suppressing density unevenness of the image. Is more preferable.

The various average particle diameters and various particle size distribution indexes of the toner particles are measured using Coulter Multisizer II (manufactured by Beckman-Coulter), and the electrolyte is measured using ISOTON-II (manufactured by Beckman-Coulter). The
In the measurement, 0.5 mg to 50 mg of a measurement sample is added as a dispersant to 2 ml of a 5% aqueous solution of a surfactant (preferably sodium alkylbenzenesulfonate). This is added to 100 ml or more and 150 ml or less of the electrolytic solution.
The electrolyte in which the sample is suspended is dispersed for 1 minute with an ultrasonic disperser, and the particle size distribution of particles having a particle size in the range of 2 μm to 60 μm is measured using a 100 μm aperture with a Coulter Multisizer II. taking measurement. The number of particles to be sampled is 50,000.
For the particle size range (channel) divided based on the measured particle size distribution, the cumulative distribution is drawn from the smaller diameter side to the volume and number, respectively, and the particle size to be 16% is the volume particle size D16v, the number particle size D16p, a particle size that is 50% cumulative is defined as a volume average particle size D50v, a cumulative number average particle size D50p, and a particle size that is 84% cumulative is defined as a volume particle size D84v and a number particle size D84p.
Using these, the volume average particle size distribution index (GSDv) is calculated as (D84v / D16v) ^1/2 and the number average particle size distribution index (GSDp) is calculated as (D84p / D16p) ^1/2 .

  The shape factor SF1 of the toner particles is preferably 110 or more and 150 or less, and more preferably 120 or more and 140 or less.

The shape factor SF1 is obtained by the following formula.
Formula: SF1 = (ML ² / A) × (π / 4) × 100
In the above formula, ML represents the absolute maximum length of the toner, and A represents the projected area of the toner.
Specifically, the shape factor SF1 is quantified mainly by analyzing a microscope image or a scanning electron microscope (SEM) image using an image analyzer, and is calculated as follows. That is, by capturing an optical microscope image of particles dispersed on the surface of a slide glass into a Luzex image analyzer using a video camera, obtaining the maximum length and projected area of 100 particles, calculating by the above formula, and obtaining the average value can get.

External additive The external additive contains fatty acid metal salt particles. In addition to the fatty acid metal salt particles, the external additive may contain other external additives such as inorganic abrasive particles and inorganic lubricant particles from the viewpoint of suppressing uneven density in the image.

Examples of the fatty acid metal salt particles include fatty acids (for example, fatty acids such as stearic acid, 12-hydroxystearic acid, behenic acid, montanic acid, lauric acid, and other organic acids) and metals (for example, calcium, zinc, magnesium, aluminum, Other examples include metal salt particles with metals (Na, Li, etc.).
Specific examples of fatty acid metal salt particles include zinc stearate, calcium stearate, iron stearate, copper stearate, magnesium palmitate, calcium palmitate, manganese oleate, lead oleate, zinc laurate, zinc palmitate And the like.
Among these, the fatty acid metal salt particles are preferably zinc stearate particles from the viewpoints of lubricity, hydrophobicity, wettability to an electrophotographic photosensitive member, and suppression of uneven density of images.

  The fatty acid metal salt particles may be mixed particles of a plurality of types of fatty acid metal salts. The fatty acid metal salt particles may be particles containing a fatty acid metal salt and other components. Examples of other components include higher fatty acid alcohols. However, the fatty acid metal salt particles contain 10% by mass or more of the fatty acid metal salt.

The median diameter based on volume of the fatty acid metal salt particles is preferably from 0.1 μm to 10.0 μm, more preferably from 0.2 μm to 10.0 μm, and more preferably from 0.2 μm to 10.0 μm from the viewpoint of suppressing density unevenness of the image. More preferably 0 μm or less.
The median diameter based on volume of the fatty acid metal salt particles is a value measured by the following method. As a measuring device, a laser diffraction / scattering particle size distribution measuring device “LA-920” (manufactured by Horiba, Ltd.) is used. The dedicated software “HORIBA LA-920 for Windows (registered trademark) WET (LA-920) Ver. 2.02” attached to LA-920 is used for setting measurement conditions and analyzing measurement data. As the measurement solvent, ion-exchanged water from which impure solids are removed in advance is used.

The inorganic abrasive particles are inorganic particles having a function of polishing the surface of the photoreceptor.
Examples of the inorganic abrasive particles include well-known abrasive particles such as inorganic oxides, nitrides, borides, and carbonates. Specific examples of the inorganic abrasive particles include silica, alumina, titania, zirconia, barium titanate, aluminum titanate, strontium titanate, magnesium titanate, zinc oxide, chromium oxide, cerium oxide, antimony oxide, and tungsten oxide. And particles of tin oxide, tellurium oxide, manganese oxide, silicon carbide, boron carbide, titanium carbide, silicon nitride, titanium nitride, boron nitride, calcium carbonate, magnesium carbonate, hydrotalcite and the like.
Among these, the inorganic abrasive particles are at least one selected from the group consisting of cerium oxide particles and strontium titanate particles from the standpoint of suppressing unevenness in image density as well as polishing properties, availability, and cost. Seed particles (especially strutium titanate) are preferred.

In addition, the surface of the inorganic abrasive particles may be subjected to a hydrophobic treatment with a hydrophobic treatment agent.
Examples of the hydrophobizing agent include titanium coupling agents such as tetrabutyl titanate, tetraoctyl titanate, isopropyl triisostearoyl titanate, isopropyl tridecylbenzenesulfonyl titanate, and bis (dioctyl pyrophosphate) oxyacetate titanate; 2-aminoethyl) aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, N-2- (N-vinylbenzylaminoethyl) 3-aminopropyl Trimethoxysilane hydrochloride, hexamethyldisilazane, methyltrimethoxysilane, butyltrimethoxysilane, isobutyltrimethoxysilane, hexyltrimethoxysilane, octyltri Silane coupling agents such as toxisilane, decyltrimethoxysilane, dodecyltrimethoxysilane, phenyltrimethoxysilane, o-methylphenyltrimethoxysilane, p-methylphenyltrimethoxysilane; silicone oil; aluminum stearate, zinc stearate, Higher fatty acid metal salts such as calcium stearate; and the like. These may be used individually by 1 type and may use 2 or more types together.
The amount of the hydrophobizing agent is usually, for example, 1 part by mass or more and 10 parts by mass with respect to 100 parts by mass of the inorganic particles.

The median diameter of the inorganic abrasive particles based on the volume is preferably from 0.1 μm to 10.0 μm, more preferably from 1.0 μm to 10.0 μm, and more preferably from 2.0 μm to 8.mu. More preferably 0 μm or less.
The median diameter based on volume of the inorganic abrasive particles is a value measured in the same manner as the median diameter of the fatty acid metal salt particles.

Examples of the inorganic lubricant particles include particles having a function of cleaving and lubricating the substance itself, or particles causing internal slip. Specific examples of the inorganic lubricant particles include mica, boron nitride, molybdenum disulfide, tungsten disulfide, talc, talc, kaolinite, montmorillonite, calcium fluoride, and graphite.
Among these, as the inorganic lubricant particles, boron nitride particles are preferable from the viewpoints of lubricity and suppression of uneven density in images.

The volume average particle diameter of the inorganic lubricant particles is preferably 0.1 μm or more and 10 μm or less, more preferably 0.2 μm or more and 10 μm or less, and further preferably 0.2 μm or more and 8 μm or less from the viewpoint of suppressing density unevenness of the image.
The volume average particle size of the inorganic lubricant particles is 50 in the cumulative frequency of the equivalent circle diameter obtained by observing 100 primary particles of the inorganic lubricant particles with a SEM (Scanning Electron Microscope) apparatus and analyzing the primary particles. % Diameter (D50v), measured by this method.

Examples of other external additives include inorganic particles having a volume average particle size of 5 nm or more and less than 100 nm (preferably 5 nm or more and 80 nm or less). The inorganic particles are externally added to the toner particles for the purpose of improving toner fluidity and chargeability. The volume average particle diameter of the inorganic particles is a value measured by the same method as the volume average particle diameter of the inorganic lubricant particles.
Examples of the inorganic particles include SiO ₂ , TiO ₂ , Al ₂ O ₃ , CuO, ZnO, SnO ₂ , CeO ₂ , Fe ₂ O ₃ , MgO, BaO, CaO, K ₂ O, Na ₂ O, and ZrO _{2. , CaO · SiO 2, K 2} O · (TiO 2) n, Al 2 O 3 · 2SiO 2, CaCO 3, MgCO 3, BaSO 4, MgSO 4 , and the like.
The surface of the inorganic particles is preferably subjected to a hydrophobic treatment. The hydrophobic treatment is performed, for example, by immersing inorganic particles in a hydrophobic treatment agent. The hydrophobizing agent is not particularly limited, and examples thereof include silane coupling agents, silicone oils, titanate coupling agents, aluminum coupling agents and the like. These may be used individually by 1 type and may use 2 or more types together.
The amount of the hydrophobizing agent is usually, for example, 1 part by mass or more and 10 parts by mass with respect to 100 parts by mass of the inorganic particles.

  Examples of other external additives include resin particles (resin particles such as polystyrene, PMMA, and melamine resin), cleaning activators (for example, fluorine-based high molecular weight particles), and the like.

  Other external additives include fatty acid metal salt particles and lubricant particles other than inorganic lubricant particles. Lubricant particles include low molecular weight polyolefins such as polypropylene, polyethylene, and polybutene; silicones that have a softening point upon heating, aliphatics such as oleic acid amide, erucic acid amide, ricinoleic acid amide, and stearic acid amide Amides; plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax, jojoba oil; animal waxes such as beeswax; montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, Fischer-Tropsch wax, etc. Mineral or petroleum waxes; and their modified particles.

Toner Manufacturing Method Next, a toner manufacturing method according to the present embodiment will be described.
The toner according to the exemplary embodiment can be obtained by externally adding an external additive to the toner particles after the toner particles are manufactured.

  The toner particles may be produced by any of a dry production method (for example, a kneading and pulverizing method) and a wet production method (for example, an aggregation coalescence method, a suspension polymerization method, a dissolution suspension method, etc.). The production method of the toner particles is not particularly limited, and a known production method is adopted.

  The toner according to the exemplary embodiment is manufactured, for example, by adding an external additive to the obtained dry toner particles and mixing them. Mixing may be performed, for example, with a V blender, a Henschel mixer, a Ladyge mixer, or the like. Furthermore, if necessary, coarse toner particles may be removed using a vibration classifier, a wind classifier, or the like.

-Carrier There is no restriction | limiting in particular as a carrier, A well-known carrier is mentioned. As a carrier, for example, a coated carrier in which the surface of a core made of magnetic powder is coated with a coating resin; a magnetic powder dispersion type carrier in which magnetic powder is dispersed and mixed in a matrix resin; a porous magnetic powder is impregnated with a resin Resin impregnated type carriers; and the like.
Note that the magnetic powder-dispersed carrier and the resin-impregnated carrier may be a carrier in which the constituent particles of the carrier are used as a core material and coated with a coating resin.

  The mixing ratio (mass ratio) of the toner and the carrier in the two-component developer is preferably toner: carrier = 1: 100 to 30: 100, and more preferably 3: 100 to 20: 100.

-Cleaning device-
As the cleaning device 13, a cleaning blade type device including a cleaning blade 131 is used.

  The cleaning blade 131 improves the wear resistance, sag resistance (permanent deformation resistance), and chipping resistance, and the first part in contact with the surface of the electrophotographic photosensitive member 7 and the other parts. It is preferable that the material of the first layer satisfies the following formulas (1) to (3).

Formula (1) 3.92 ≦ M ≦ 29.42
Formula (2) 0 <α ≦ 0.294
Formula (3) S ≧ 250
[In the formulas (1) to (3), M represents a 100% modulus (MPa), and α represents a strain amount change (Δ strain amount) when the strain amount is 100% or more and 200% or less in the stress-strain curve. ) Represents the ratio of stress change (Δstress) to Δ {stress / Δstrain amount = (stress at 200% strain−stress at 100% strain) / (200−100)} (MPa /%). , Elongation at break (%) measured based on JIS K6251 (using dumbbell-shaped No. 3 test piece). ]

The 100% modulus M shown in the formula (1) is obtained from the stress at the time of 100% strain using a dumbbell-shaped No. 3 test piece and measuring at a tensile speed of 500 mm / min in accordance with JISK6251 (1993). . In addition, the measuring apparatus used the Toyo Seiki Co., Ltd. product and the strograph AE elastomer.
On the other hand, α shown in Expression (2) is obtained from a stress-strain curve. The stress and strain amount are determined by the procedure / method described below. That is, in accordance with JISK6251 (1993), a dumbbell-shaped No. 3 test piece is used and measured at a tensile speed of 500 mm / min, and is obtained from stress at 100% strain and stress at 200% strain. In addition, the measuring apparatus used the Toyo Seiki Co., Ltd. product and the strograph AE elastomer.

  Here, the cleaning blade 131 includes 1) a first layer (an example of the first part) that contacts the surface of the electrophotographic photosensitive member 7 and a second layer (an example of the second part) as a back layer on the back of the first layer. And 2) a contact portion (an example of the first part) disposed at the corner of the blade that contacts the surface of the electrophotographic photosensitive member 7 and a support part (an example of the second part) that supports the contact part. The structure which has these. The second layer as the back layer may have a single layer configuration or a multilayer configuration of two or more layers.

  Hereinafter, a cleaning blade 131 having a two-layer structure including a first layer and a second layer (single layer) as a back layer will be described in detail.

-1st layer When the material of the 1st layer satisfy | fills Formula (1), it will become easy to improve abrasion resistance, exhibiting favorable cleaning property. The 100% modulus M is preferably in the range of 5 MPa or more and 20 MPa or less, and more preferably in the range of 6.5 MPa or more and 15 MPa or less.

When the first layer material satisfies the formulas (2) and (3), chipping resistance is likely to increase.
Α is preferably 0.2 or less, more preferably 0.1 or less, and the closer to 0, which is the lower limit of physical properties, the better.
The breaking elongation S is preferably 300% or more, and more preferably 350% or more. On the other hand, the elongation at break S is preferably 500% or less, more preferably 450% or less, and still more preferably 400% or less, from the viewpoint of wear resistance.

  The glass transition temperature Tg of the first layer material is preferably not more than the lower limit (for example, 10 ° C.) of the operating environment temperature of the apparatus from the viewpoint of the stability of the contact pressure of the cleaning blade 131.

The glass transition temperature of the first layer material is obtained as a peak temperature of tan δ (loss tangent) by measuring temperature dispersion with a viscoelasticity measuring device.
Here, the tan δ value is derived from the storage and loss elastic modulus described below. When a sinusoidal distortion is applied to the linear elastic body in a steady vibration manner, the stress is expressed by the following equation (4). | E * | is called the complex elastic modulus. Further, from the theory of rheology, the elastic body component is represented by equation (5), and the viscous body component is represented by equation (6). Here, E ′ is called storage elastic modulus, and E ″ is called loss elastic modulus. δ represents a phase difference angle between stress and strain, and is called “mechanical loss angle”.
The tan δ value is expressed by E ″ / E ′ as shown in Equation (7), and is called “loss sine”. The larger the value, the more the linear elastic body has rubber elasticity. .
Formula (4) σ = | E * | γ cos (ωt)
Formula (5) E ′ = | E * | cos δ
Formula (6) E ″ = | E * | sin δ
Expression (7) tan δ = E ″ / E ′
The tan δ value was measured using a Leopectra-DVE-V4 (manufactured by Rheology Co., Ltd.) with a static strain of 5% and a 10 Hz sine wave tensile vibration in a temperature range of −60 ° C. to 100 ° C.

  The rebound resilience R of the first layer material is preferably 10% or more, more preferably 15% or more in an environment where the temperature is 10 ° C. or more, which is a substantial lower limit of the use environment temperature. Preferably, 20% or more is more preferable. When the rebound resilience R of the first layer material is 10% or more, stick-and-slip behavior (microscopic self-excited vibration phenomenon caused by repeated adhesion and slipping of the first layer to the surface of the electrophotographic photoreceptor 7) Is likely to occur, and plastic deformation of the first layer is difficult to occur. Thereby, the adhesiveness between the first layer and the electrophotographic photosensitive member 7 is improved, and the occurrence of defective cleaning is easily suppressed. The rebound resilience R is a value measured according to JISK6255 (1996).

Next, materials that satisfy the expressions (1) to (3) will be described.
The material satisfying the formulas (1) to (3) is not particularly limited as long as it is an elastomer material, but an elastomer material including a hard segment and a soft segment is particularly preferable. When the elastomer material contains both the hard segment and the soft segment, it becomes easy to satisfy the physical properties shown in the formulas (1) to (3), and both the wear resistance and chipping resistance are increased to a higher level. This is because they can be compatible.
The “hard segment” and the “soft segment” are the materials that make up the former in the elastomer material and are relatively harder than the materials that make up the latter. Means a segment made of a material relatively softer than the material constituting the former.

Here, the glass transition temperature of the elastomer material containing the hard segment and the soft segment is preferably in the range of −50 ° C. to 30 ° C., and preferably in the range of −30 ° C. to 10 ° C. When the glass transition temperature is 30 ° C. or lower, the occurrence of embrittlement tends to be suppressed in a practical temperature range where the cleaning blade is used. Further, when the glass transition temperature is −50 ° C. or higher, sufficient hardness and stress can be easily obtained in the actual use region.
Therefore, in order to realize the glass transition temperature in the above range, the glass transition temperature of the material constituting the hard segment of the elastomer material (hereinafter sometimes referred to as “hard segment material”) is 30 ° C. or higher and 100 ° C. or lower. Preferably, it is in the range of 35 ° C. or more and 60 ° C. or less. On the other hand, the glass transition temperature of the material constituting the soft segment (hereinafter sometimes referred to as “soft segment material”) is preferably in the range of −100 ° C. or higher and −50 ° C. or lower, and −90 ° C. or higher. More preferably, it is within the range of 60 ° C. or less.

When using a hard segment material and a soft segment material having a glass transition temperature in the above range, the mass ratio of the material constituting the hard segment to the total amount of the hard segment material and the soft segment material (hereinafter referred to as “hard segment material ratio”) Is preferably in the range of 46% by mass to 96% by mass, more preferably in the range of 50% by mass to 90% by mass, and more preferably in the range of 60% by mass to 85% by mass. More preferably within the range.
When the hard segment material ratio is 46% by mass or more, the wear resistance at the tip of the first layer is secured, and the occurrence of wear is easily suppressed. As a result, good cleaning properties can be easily maintained over a long period of time. Further, when the hard segment material ratio is 96% by mass or less, the tip of the first layer does not become too hard, and flexibility and stretchability are easily obtained. Thereby, generation | occurrence | production of a chip | tip is suppressed and it becomes easy to maintain favorable cleaning property over a long period of time.

The combination of the hard segment material and the soft segment material is not particularly limited, and is selected from known resin materials so that one is relatively hard with respect to the other and the other is relatively soft with respect to the other. However, the following combinations are preferred.
That is, it is preferable to use a polyurethane resin as the hard segment material. In this case, the weight average molecular weight of the polyurethane resin is preferably in the range of 1000 or more and 4000 or less, and more preferably in the range of 1500 or more and 3500 or less.
When the weight average molecular weight is 1000 or more, the elasticity of the polyurethane resin constituting the hard segment is not easily lost when the cleaning blade 131 is used in a low temperature environment. Thereby, it becomes easy to suppress poor cleaning. On the other hand, when the weight average molecular weight is 4000 or less, the permanent set of the polyurethane resin constituting the hard segment is difficult to be excessively increased. As a result, the leading edge of the first layer can maintain a contact pressure with respect to the electrophotographic photosensitive member 7, so that cleaning defects are easily suppressed.
In addition, as a polyurethane resin used as a hard segment material, the Daicel chemical company make, Plaxel 205, Plaxel 240, etc. are mentioned, for example.

  The pressing pressure of the cleaning blade 131 is preferably set to 1.7 gf / mm or more and 6.5 gf / mm or less, more preferably 2.0 gf / mm or more to 6.0 gf / mm or less. When the pressing pressure is equal to or higher than the lower limit, toner cleaning failure is easily suppressed even when a high-hardness blade is used. When the pressing pressure is less than the above upper limit, friction with the photoconductor does not become excessively high, and torque rise, photoconductor wear, generation of streaks due to chipping of the blade edge, and generation of ghost due to friction with the photoconductor are suppressed. It becomes easy to be done.

-Transfer device-
Examples of the transfer device 40 include known transfer chargers such as a contact transfer charger using a belt, a roller, a film, a rubber blade, and the like, a scorotron transfer charger using a corona discharge, and a corotron transfer charger. Can be mentioned.

-Intermediate transfer member-
As the intermediate transfer member 50, a belt-like member (intermediate transfer belt) containing polyimide, polyamideimide, polycarbonate, polyarylate, polyester, rubber or the like having semiconductivity is used. Further, as the form of the intermediate transfer member, a drum-like member may be used in addition to the belt-like member.

FIG. 5 is a schematic configuration diagram illustrating another example of the image forming apparatus according to the present embodiment.
An image forming apparatus 120 shown in FIG. 5 is a tandem multicolor image forming apparatus equipped with four process cartridges 300. In the image forming apparatus 120, four process cartridges 300 are arranged in parallel on the intermediate transfer member 50, and one electrophotographic photosensitive member is used for one color. The image forming apparatus 120 has the same configuration as that of the image forming apparatus 100 except that it is a tandem system.

  The image forming apparatus (process cartridge) according to the present embodiment described above is not limited to the above configuration, and a known configuration may be applied.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

<Production of photoconductor>
[Photoreceptor (1)]
-Production of undercoat layer-
Zinc oxide: (average particle diameter 70 nm: manufactured by Teica Co., Ltd .: specific surface area value 15 m ² / g) 100 parts by mass was stirred and mixed with 500 parts by mass of toluene, and a silane coupling agent (KBM503: manufactured by Shin-Etsu Chemical Co., Ltd.) 1.3 Part by mass was added and stirred for 2 hours. Thereafter, toluene was distilled off under reduced pressure and baked at 120 ° C. for 3 hours to obtain a silane coupling agent surface-treated zinc oxide.
110 parts by mass of surface-treated zinc oxide was stirred and mixed with 500 parts by mass of tetrahydrofuran, a solution prepared by dissolving 0.6 parts by mass of alizarin in 50 parts by mass of tetrahydrofuran was added, and the mixture was stirred at 50 ° C. for 5 hours. . Then, the zinc oxide to which alizarin was imparted by filtration under reduced pressure was filtered off, and further dried at 60 ° C. under reduced pressure to obtain alizarin imparted zinc oxide.

60 parts by mass of this alizarin-provided zinc oxide and a curing agent (blocked isocyanate Sumijoule 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.): 13.5 parts by mass and 15 parts by mass of butyral resin (ESREC BM-1, manufactured by Sekisui Chemical Co., Ltd.) 38 parts by mass of methyl ethyl ketone dissolved in 85 parts by mass of methyl ethyl ketone and 25 parts by mass of methyl ethyl ketone were mixed and dispersed in a sand mill for 2 hours using 1 mmφ glass beads to obtain a dispersion.
Dioctyltin dilaurate: 0.005 parts by mass and silicone resin particles (Tospearl 145, manufactured by Momentive Performance Materials): 40 parts by mass are added to the resulting dispersion as a catalyst, and an undercoat layer-forming coating solution is added. Obtained.

  A cylindrical aluminum substrate having a diameter of 30 mm, a length of 340 mm, and a thickness of 1 mm was prepared as a conductive substrate, and the resulting coating solution for forming the undercoat layer was applied onto the cylindrical aluminum substrate by a dip coating method. Drying and curing at 40 ° C. for 40 minutes were performed to obtain an undercoat layer having a thickness of 18.7 μm.

-Fabrication of charge generation layer-
Bragg angles (2θ ± 0.2 °) of X-ray diffraction spectrum using Cukα characteristic X-ray as a charge generating material are at least 7.3 °, 16.0 °, 24.9 °, 28.0 ° A mixture consisting of 15 parts by mass of hydroxygallium phthalocyanine having a diffraction peak, 10 parts by mass of vinyl chloride / vinyl acetate copolymer resin (VMCH, manufactured by Nihon Unicar) as a binder resin, and 200 parts by mass of n-butyl acetate. The mixture was dispersed for 4 hours in a sand mill using glass beads having a diameter of 1 mmφ. To the obtained dispersion, 175 parts by mass of n-butyl acetate and 180 parts by mass of methyl ethyl ketone were added and stirred to obtain a coating solution for forming a charge generation layer.
The resulting charge generation layer forming coating solution is dip coated on the undercoat layer previously formed on the cylindrical aluminum substrate and dried at room temperature (25 ° C.) to form a charge generation layer having a thickness of 0.2 μm. Formed.

-Preparation of charge transport layer-
First, a polycarbonate copolymer (1) was obtained as follows.
In a flask equipped with a phosgene blowing tube, a thermometer and a stirrer, 106.9 g (0.398 mol) of 1,1-bis (4-hydroxyphenyl) cyclohexane (hereinafter referred to as “Z”) under a nitrogen atmosphere, 4'-dihydroxybiphenyl (hereinafter referred to as “BP”) 24.7 g (0.133 mol), hydrosulfite 0.41 g, 9.1% aqueous sodium hydroxide solution 825 ml (sodium hydroxide 2.018 mol), chloride 500 ml of methylene was charged and dissolved, and the mixture was kept in a range of 18 ° C. or higher and 21 ° C. or lower with stirring, and 76.2 g (0.770 mol) of phosgene was required for 75 minutes to perform a blowing phosgenation reaction. After completion of the phosgenation reaction, 1.11 g (0.0075 mol) of p-tert-butylphenol and 54 ml of 25% aqueous sodium hydroxide solution (0.266 mol of sodium hydroxide) were added and stirred, and 0.18 mL (0.0013) of triethylamine was added along the way. Mol) was added and reacted at a temperature of 30 ° C. to 35 ° C. for 2.5 hours. The separated methylene chloride phase was acid washed and washed with water until inorganic salts and amines disappeared, and then methylene chloride was removed to obtain a polycarbonate copolymer (1). This polycarbonate had a molar ratio of the constituent units of Z and BP of 75:25.

  Next, 25 parts by mass of N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1 ′] biphenyl-4,4′-diamine (TPD), the following structural formula (A) And 20 parts by mass of the compound represented by the formula (1) and 55 parts by mass of the polycarbonate copolymer (1) (viscosity average molecular weight: 50,000) as a binder resin are added to 560 parts by mass of tetrahydrofuran and 240 parts by mass of toluene, and dissolved. A coating solution was obtained. This coating solution was applied onto the charge generation layer and dried at 135 ° C. for 45 minutes to form a charge transport layer having a thickness of 20 μm.

-Production of protective layer-
40 parts by weight of “Exemplary Compound (Id) -28” as a reactive charge transporting material (chain polymerizable charge transporting material) was dissolved in 20 parts by weight of tetrahydrofuran (THF), and then 15 parts by weight of isobutyl acetate. As a reactive material (chain polymerizable material), a solution containing 60 parts by mass of a compound represented by the following structural formula (B), which is distilled under reduced pressure, in 20 parts by mass of THT, and a polymerization initiator VE-073 2 parts by weight (manufactured by Wako Pure Chemical Industries, Ltd.) and 235 parts by weight of isobutyl acetate were mixed and stirred and mixed at room temperature for 12 hours to prepare a coating solution for forming a protective layer.

  Next, the obtained coating liquid for forming a protective layer was applied on the charge transport layer previously formed on the cylindrical aluminum substrate by a ring coating method at a push-up speed of 180 mm / min. Thereafter, a curing reaction was performed in a nitrogen dryer having an oxygen concentration meter at a temperature of 160 ± 5 ° C. for 60 minutes with an oxygen concentration of 200 ppm or less to form a protective layer. The film thickness of the protective layer was 11 μm.

  A photoreceptor (1) was produced as described above. The produced photoreceptor (1) was mounted on an image forming apparatus “Fuji Xerox Co. (Docentre-IV C2260)”. Then, an image pattern shown in FIG. 6 was output by the image forming apparatus, and an initial image quality test for confirming that an image having a target image density was obtained was performed.

[Photoconductors (2) to (27), Comparative photoconductors (C2) to (C2), Reference photoconductors (R1) to (R2)]
In the same manner as described in the photoreceptor (1), an undercoat layer, a charge generation layer, and a charge transport layer were sequentially formed on a cylindrical aluminum substrate. Then, according to Table 1, the composition of the coating liquid for forming the protective layer [reactive charge transport material (indicated in table, “RCTM”) type and amount, non-reactive charge transport material (indicated in table, “CTM”) The protective layer is formed in the same manner as the photoconductor (1) except that the type and amount, the reactive material (indicated as “RM” in the table)], and the thickness of the protective layer are changed. To (27), comparative photoreceptors (C2) to (C2), and reference photoreceptors (R1) to (R2) were produced. Then, an initial image quality test was performed in the same manner as the photoconductor (1).
As a result of the initial image quality test, the density of the reference photoreceptor (R1) significantly decreased, and the protective layer having a thickness of 11 μm could not function as a photoreceptor.
The reference photoconductor (23) having a protective layer having a thickness of 6 μm has a low wear rate and can have a long life, but the photoconductor (1) and the like that can increase the thickness of the protective layer. However, it is possible to extend the life.

[Comparative Photoconductor (C1)]
In the same manner as in the method described in Photoreceptor 1, an undercoat layer and a charge generation layer were sequentially formed on a cylindrical aluminum substrate by coating.
Next, 25 parts by mass of N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1 ′] biphenyl-4,4′-diamine (TPD), represented by structural formula (A) 20 parts by mass of a compound to be obtained, 55 parts by mass of a polycarbonate copolymer (1) (viscosity average molecular weight: 50,000) as a binder resin, 7.3 parts by mass of PTFE fine particles (Lublon L-2, manufactured by Daikin), a fluororesin (GF-400, manufactured by Toa Gosei Co., Ltd.) 0.35 parts by mass is added to 560 parts by mass of tetrahydrofuran and 240 parts by mass of toluene and dissolved, and a high-pressure wet medialess atomizer (Nanomizer NMS-200ED, manufactured by Nanomizer) is used. Dispersion treatment was performed to obtain a charge transport layer coating solution. This coating solution was applied onto the charge generation layer and dried at 135 ° C. for 45 minutes to form a charge transport layer having a thickness of 40 μm.
A comparative photoreceptor (C1) was produced as described above. Then, an initial image quality test was performed in the same manner as the photoconductor (1).

<Production of toner particles>
[Preparation of cyan (C color) toner particles (1)]
-Synthesis of crystalline polyester resin (1)-
In a heat-dried three-necked flask, 124 parts by mass of ethylene glycol, 22.2 parts by mass of sodium dimethyl 5-sulfoisophthalate, 213 parts by mass of dimethyl sebacate, and 0.3 parts by mass of dibutyltin oxide as a catalyst were added. The air in the container was brought into an inert atmosphere with nitrogen gas by depressurization, and stirring was performed at 180 ° C. for 5 hours by mechanical stirring. Thereafter, the temperature was gradually raised to 220 ° C. under reduced pressure, and the mixture was stirred for 4 hours. When the mixture became viscous, it was cooled with air, the reaction was stopped, and 220 parts by mass of crystalline polyester resin (1) was synthesized.
As a result of molecular weight measurement (polystyrene conversion) by gel permeation chromatography, the obtained crystalline polyester resin (1) had a weight average molecular weight (M _w ) of 19000 and a number average molecular weight (M _n ) of 5800.
Moreover, when the melting point (Tm) of the crystalline polyester resin (1) was measured by a differential scanning calorimeter (DSC) by the above-described measuring method, it had a clear peak, and the peak top temperature was 70 ° C. Met.

-Preparation of resin dispersion (1)-
150 parts by mass of the crystalline polyester resin (1) is put in 850 parts by mass of distilled water, mixed and stirred with a homogenizer (manufactured by IKA Japan: Ultra Tarax) while heating to 80 ° C., and a resin particle dispersion (1 ) Next, 250 parts by mass of phthalocyanine pigment (manufactured by Dainichi Seika Co., Ltd .: PV FAST BLUE), 20 parts by mass of an anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK), 700 parts by mass of ion-exchanged water After mixing and dissolving, a colorant dispersion (1) was prepared by dispersing using a homogenizer (manufactured by IKA: Ultratarax) to disperse the colorant (phthalocyanine pigment).

-Preparation of aggregated particles-
Resin particle dispersion (1) 2400 parts by weight, colorant dispersion (1) 100 parts by weight, release agent particle dispersion 63 parts by weight, aluminum sulfate 6 parts by weight (manufactured by Wako Pure Chemical Industries, Ltd.), ion-exchanged water 100 Part by mass is contained in a round stainless steel flask and adjusted to pH 2.0, and then dispersed using a homogenizer (manufactured by IKA: Ultra Turrax T50), and then heated to 60 ° C. in an oil bath for heating. Heated with stirring. After maintaining at 60 ° C. for 2 hours, observation with an optical microscope confirmed that aggregated particles having an average particle size of about 4.3 μm were formed. After further heating and stirring at 60 ° C. for 2 hours, observation with an optical microscope confirmed that aggregated particles having a volume average particle diameter of 3.3 μm were formed.
The pH of this aggregated particle liquid was 2.4. Therefore, an aqueous solution obtained by diluting sodium carbonate (manufactured by Wako Pure Chemical Industries, Ltd.) to 0.5% by mass was gently added to adjust the pH to 5.0, and then heated to 75 ° C. while stirring was continued for 3 hours. Retained.
Thereafter, the reaction product was filtered, sufficiently washed with ion-exchanged water, and then dried using a vacuum dryer to obtain cyan toner particles (1). The resulting cyan toner particle toner had a melting point of 65 ° C.
The resulting cyan toner particles (1) had a volume average particle size = 3.2 μm and a shape factor SF1 = 133.

[Yellow (Y) toner particles (1)]
Yellow (Y) toner particles (1) were obtained in the same manner as in the production of cyan toner particles (1) except that a yellow-azo pigment was used instead of the phthalocyanine pigment.

[Magenta (M) toner particles (1)]
Magenta (M color) toner particles (1) were obtained in the same manner as in the production of cyan toner particles (1) except that quinacridone pigment was used instead of phthalocyanine pigment.

[Black (K color) toner particles (1)]
Black toner particles (1) were obtained with the same formulation except that carbon black was used in place of the phthalocyanine pigment in the production of cyan toner particles (1).

<Production of developer>
[Developer 1]
To 100 parts by mass of each of the obtained four color toner particles (1), 0.5 parts by mass of hexamethyldisilazane-treated silica particles (volume average particle size of 40 nm) as an external additive, and isobutyltrimethoxy in metatitanic acid 0.7 parts by mass of titanium compound particles (volume average particle size 30 nm) obtained by firing after 50% silane treatment and zinc stearate particles (Nissan Electol MZ-2, median based on volume) as fatty acid metal salt particles 0.18 parts by mass with a diameter of 1.5 μm, manufactured by NOF Corporation) and a 75 L Henschel mixer for 10 minutes, and then sieved with a wind sieving machine Hivolta 300 (manufactured by Toyo Hitec Co., Ltd.). Each toner (1) was produced.

  Next, a mixture of 0.15 parts by mass of vinylidene fluoride and 1.35 parts by mass of a copolymer of methyl methacrylate and trifluoroethylene (polymerization ratio 80:20) with respect to 100 parts by mass of the ferrite core. Using a kneader apparatus, a ferrite core having an average particle diameter of 50 μm was coated with a resin to produce a carrier.

  Then, 8 parts by mass of each of the obtained four color toners (1) and 100 parts by mass of the obtained carrier were mixed with a 2 liter V blender to prepare four color developers. The resulting set of four color developers was designated as developer (1).

[Developer 2]
In the production of each toner of four colors (1), except that the amount of zinc stearate particles was changed from 0.18 parts by mass to 0.12 parts by mass, the same procedure as for each toner of four colors (1) was performed. Each color toner (2) was prepared.
Then, a developer (2) was produced in the same manner as the developer (1), except that the obtained four color toners (2) were used instead of the four color toners (1).

[Developer 3]
In the production of each toner of four colors (1), except that the amount of zinc stearate particles was changed from 0.18 parts by mass to 0.03 parts by mass, Each color toner (3) was prepared.
Then, a developer (3) was produced in the same manner as the developer (1) except that each of the obtained four color toners (3) was used instead of each of the four color toners (1).

[Developer 4]
Instead of zinc stearate particles (Nissan Electol MZ-2, volume-based median diameter 1.5 μm, manufactured by NOF Corporation) in the preparation of each toner of four colors (1), zinc stearate particles (zinc stearate) Each of the four color toners (4) was prepared in the same manner as each of the four color toners (1) except that S, a volume-based median diameter of 12 μm, manufactured by NOF Corporation was used.
Then, a developer (4) was produced in the same manner as the developer (1) except that the obtained four color toners (4) were used in place of the four color toners (1).

[Developer 5]
Each of the four color toners (1) was prepared in the same manner as each of the four color toners (1) except that the zinc stearate particles were not added.
Then, a developer (5) was produced in the same manner as the developer (1), except that the obtained four color toners (5) were used in place of the four color toners (1).

[Developer 6]
In the production of each toner of four colors (1), except that the amount of zinc stearate particles was changed from 0.18 parts by mass to 0.25 parts by mass, the same procedure as for each toner of four colors (1) was performed. Each color toner (6) was prepared.
Then, a developer (6) was produced in the same manner as the developer (1), except that the obtained four color toners (6) were used instead of the four color toners (1).

[Developer 7]
In the production of each toner of four colors (1), except that the amount of zinc stearate particles was changed from 0.18 parts by mass to 0.06 parts by mass, Each color toner (7) was prepared.
Then, a developer (7) was produced in the same manner as the developer (1), except that the obtained four color toners (7) were used in place of the four color toners (1).

[Developer 8]
In preparation of each toner of four colors (1), each toner particle (1) of four colors is changed to the following toner particles (2), and the amount of zinc stearate particles is 0.18 parts by mass to 0.12 parts by mass. Each of the four color toners (8) was prepared in the same manner as each of the four color toners (1) except that the four color toners (1) were changed.
Then, a developer (8) was produced in the same manner as the developer (1) except that the obtained four colors of toner (8) were used instead of the four colors of toner (1).

-Production of toner particles (2)-
After confirming the formation of aggregated particles having an average particle size of about 4.3 μm in the production of the four color toner particles (1), the mixture was further heated and stirred at 60 ° C. for 1 hour. When observed with an optical microscope, it was confirmed that aggregated particles having a volume average particle diameter of 4.5 μm were formed.
The pH of this aggregated particle liquid was 2.4. Therefore, an aqueous solution obtained by diluting sodium carbonate (manufactured by Wako Pure Chemical Industries, Ltd.) to 0.5% by mass was gently added to adjust the pH to 5.0, and then heated to 75 ° C. while stirring was continued for 3 hours. Retained.
Thereafter, the reaction product was filtered, sufficiently washed with ion-exchanged water, and then dried using a vacuum dryer to obtain toner (2). The melting point of the obtained toner particles was 65 ° C.
Thereafter, the reaction product was filtered, sufficiently washed with ion-exchanged water, and then dried using a vacuum dryer to obtain toner particles (2). The resulting toner particles (2) had a melting point of 65 ° C.
The obtained toner particles (2) had a volume average particle size = 4.5 μm and a shape factor SF1 = 133.

[Developer 9]
Instead of zinc stearate particles (Nissan Electol MZ-2, volume-based median diameter 1.5 μm, manufactured by NOF Corporation) in the preparation of each toner of four colors (1), zinc stearate particles (zinc stearate) Each of the four color toners (9) was prepared in the same manner as the four color toners (1) except that FP, a volume-based median diameter of 5.5 μm, manufactured by NOF Corporation was used.
Then, a developer (9) was produced in the same manner as the developer (1), except that the obtained four color toners (9) were used in place of the four color toners (1).

[Developer 10]
Instead of zinc stearate particles (Nissan Electol MZ-2, volume-based median diameter 1.5 μm, manufactured by NOF Corporation) in the preparation of each toner of four colors (1), zinc stearate particles (zinc stearate) Each toner of each of the four colors (1) was used except that the amount of zinc stearate particles was changed from 0.18 parts by mass to 0.005 parts by mass using FP, a volume-based median diameter of 5.5 μm, manufactured by NOF Corporation. In the same manner as above, each toner (10) of four colors was produced.
Then, a developer (10) was produced in the same manner as the developer (1) except that each of the obtained four color toners (10) was used in place of the four color toners (10).

<Production of cleaning blade>
[Cleaning blade (1)]
First, a member for the first layer was formed as follows.
First, as the polyol component, polycaprolactone polyol (Daicel Chemical Industries, Plaxel 205, average molecular weight 529, hydroxyl value 212 KOHmg / g) and polycaprolactone polyol (Daicel Chemical Industries, Plaxel 240, average molecular weight 4155, hydroxyl value 27 KOHmg / g). ) And a soft segment material made of an acrylic resin containing 2 or more hydroxyl groups (Act Flow UMB-2005B, manufactured by Soken Chemical Co., Ltd.) at a ratio of 8: 2 (mass ratio). did.

Next, with respect to 100 parts of the mixture of the hard segment material and the soft segment material, 4,4′-diphenylmethane diisocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd., Millionate MT, hereinafter referred to as “MDI”) is used as the isocyanate compound. Part was added and reacted at 70 ° C. for 3 hours under a nitrogen atmosphere. The amount of the isocyanate compound used in this reaction is selected so that the ratio of isocyanate group to hydroxyl group (isocyanate group / hydroxyl group) contained in the reaction system is 0.5.
Subsequently, 34.3 parts of the above isocyanate compound was further added and reacted at 70 ° C. for 3 hours under a nitrogen atmosphere to obtain a prepolymer.
In addition, the total amount of the isocyanate compound utilized when using the prepolymer is 40.56 parts.

  Next, the prepolymer was heated to 100 ° C., degassed for 1 hour under reduced pressure, and then mixed with 1,4-butanediol and trimethylolpropane (mass ratio = 60) with respect to 100 parts of the prepolymer. 7.14 parts of / 40) was added and mixed well for 3 minutes so as not to entrain the foam, to prepare a first layer forming composition A1.

  Next, the composition A1 for forming the first layer was poured into a centrifugal molding machine whose mold was adjusted to 140 ° C., and a curing reaction was performed for 1 hour to form a flat plate-like first layer.

On the other hand, composition A1 for forming a second layer prepared by the following method was prepared as a member for the second layer.
Diphenylmethane-4,4-diisocyanate was mixed with dehydrated polytetramethyl ether glycol and reacted at 120 ° C. for 15 minutes, and the resulting prepolymer was used in combination with 1,4-butadiol and trimethylolpropane as curing agents. Using.

  Next, as described above, the second layer forming composition A1 is poured into a centrifugal molding machine after forming the first layer into a flat plate shape and cured, and the second layer is formed on the back surface of the first layer. Formed.

And the flat plate which formed the 2nd layer on the back surface of the obtained 1st layer was cooled after bridge | crosslinking at 110 degreeC for 24 hours, cut to the target dimension, 1st layer thickness 0.5mm, 2nd layer A cleaning blade (1) having a thickness of 1.5 mm (thickness ratio of 25% of the total thickness) was obtained.
In addition, it was as follows when the physical property in a 1st layer single layer was measured.
・ 100% modulus M = 7.4 MPa
・ Α = 0.09 (MPa /%)
・ Elongation at break S = 535%
・ Rebound resilience R = 35%
-Glass transition temperature Tg = -8 ° C.

<Examples 1 to 28, Comparative Examples 1 to 8>
In a combination according to Table 3, the photoconductor, the developer, and the cleaning blade were mounted on an image forming apparatus (“Doccentre-IV C2260” manufactured by Fuji Xerox Co., Ltd.) equipped with a contact charging device. This image forming apparatus was used as an image forming apparatus of Examples 1 to 28 and Comparative Examples 1 to 8.

<Evaluation>
An image pattern shown in FIG. 6 was output to A4 paper by the image forming apparatus of each example, and an initial image quality test was performed to confirm that an image having a target image density was obtained.
Next, a job pattern for continuously outputting three image patterns shown in FIG. 6 on A4 paper is as follows: 1) 70,000 sheets at normal temperature and normal humidity (temperature 20 ° C., humidity 50% RH) (photoconductor 200,000 rotation ( 2) 70,000 sheets at low temperature and low humidity (temperature 10 ° C., humidity 15% RH), 3) 70,000 sheets at high temperature and high humidity (temperature 29 ° C., humidity 85% RH), respectively An output test was performed. The output of this image pattern was performed by transporting A4 paper [P paper made by Fuji Xerox] in the short direction.

At the end of the output test in each environment, 1) evaluation of the electrical characteristics of the photoconductor, 2) the average wear rate (nm / 1000 rotations), the maximum wear rate (nm / 1000 rotations), and the minimum wear rate ( 3) Evaluation of the wear cross-sectional area (μm ² ) of the cleaning blade, 4) Evaluation of chipping of the cleaning blade, 5) Evaluation of image quality, and 6) Evaluation of slipping through the external additive.

(Electrical characteristics of photoconductor)
For the electrical characteristics of the photoreceptor, the residual potential (Rp) after static elimination was measured using a surface potentiometer (Trek, Trek 334), and a surface potential probe was provided in the region to be measured (surface of the electrophotographic photoreceptor) 1 mm from the position), and the difference (ΔRp) between the initial residual potential and the residual potential after printing 50,000 sheets of each environment was calculated. The residual potential was evaluated according to the following evaluation criteria.
A +: Less than 20V A: 20V or more and less than 50V B: 50V or more and less than 80V C: 80V or more

(Photoconductor wear rate)
The average wear rate of the photoconductor, the maximum wear rate of the photoconductor, and the minimum wear rate of the photoconductor were measured by the methods described above. In the table, the unit “(nm / 1000 rotations)” is omitted. In addition, the notation of each wear rate in each table is as follows.
“Wm”: average wear rate of the photoconductor in a normal temperature / humidity environment “Wmmax”: the maximum wear rate of the photoconductor in a normal temperature / humidity environment • “Wmmin”: minimum wear of the photoconductor in a normal temperature / humidity environment Rate “Wl”: average wear rate of the photoreceptor in a low temperature and low humidity environment • “Wlmax”: maximum wear rate of the photoreceptor in a low temperature and low humidity environment • “Wlmin”: minimum wear rate of the photoreceptor in a low temperature and low humidity environment “Wh”: average wear rate of the photoconductor in a high temperature and high humidity environment “Whmax”: maximum wear rate of the photoconductor in a high temperature and high humidity environment • “Whmin”: minimum wear rate of the photoconductor in a high temperature and high humidity environment

(Wear sectional area of the cleaning blade)
The portion where the cleaning blade was in contact with the photoreceptor was observed with a laser microscope, and the wear cross section was measured. This wear cross-sectional area was determined as the area obtained by subtracting the wear cross-sectional area after the output test from the cross-sectional area of the portion where the initial blade was in contact with the photoreceptor. Then, the wear cross-sectional area of the cleaning blade was evaluated according to the following evaluation criteria.
A: Less than 10 μm ² A: 10 μm ² or more and less than 20 μm ² B: 20 μm ² or more and less than 40 μm ² C: 40 μm ² or more

(Cleaning blade missing)
After the output test in each environment, one solid image with an image density of 30% was further output on A4 paper, and the occurrence of streaks on the image was observed. The chipping of the cleaning blade was evaluated according to the following evaluation criteria.
A: No streaking A: 3 or less minor streaks B: 3 or more and less than 10 streaks C: 10 or more clear streaks

(image quality)
After completion of the output test in each environment, one solid image having an image density of 30% was further output on A4 paper, the obtained image was observed, and image flow and density unevenness were evaluated according to the following evaluation criteria.

-Image flow evaluation criteria-
A: No image flow at all A: No image flow causing a problem in image quality B: Some image flow generated C: Image flow causing a problem in image quality

-Evaluation criteria for uneven density-
A +: No density unevenness occurred A: No density unevenness causing image quality problems B: Some density unevenness occurred C: Density unevenness caused image quality problems

(External additive slipping through)
After the output test in each environment, one solid image with an image density of 30% was output on A4 paper, and then the photoconductors at a total of three locations, that is, the central portion in the axial direction and the portions 5 cm from each end. The surface was observed with a laser microscope, and the average number of external additives observed in a region of 100 μm ² was evaluated according to the following evaluation criteria.
A +: The number of external additives is less than 5 A: The number of external additives is 5 or more and less than 10 B: The number of external additives is 10 or more and less than 20 C: The number of external additives is 20 or more

(Comprehensive evaluation)
The above evaluations were integrated to make an overall evaluation of the electrophotographic photosensitive member and the image forming system. The evaluation criteria are as follows.
A +: Particularly excellent A: Excellent B: There are some problems, but there are no major practical problems C: There are practical problems

  Hereinafter, details and evaluation results of each example are listed in Tables 1 to 6.

From the above results, it can be seen that in this example, the evaluation of density unevenness is better than in the comparative example.
In this example, it can be seen that the electrical characteristics (residual potential) of the photoreceptor, the wear cross-sectional area of the cleaning blade (μm ² ), the chipping of the cleaning blade, the external additive slipping, and the image flow are also evaluated well.

  When three types of image patterns having different image densities as shown in FIG. 6 are continuously output from the evaluation result of the comparative example, the wear rate of the photoconductor greatly varies depending on the image pattern, and the photoconductor (protective layer) It can be seen that a difference in film thickness is likely to appear as density unevenness. Since the wear of the photoconductor is likely to proceed at a low temperature where the hardness of the cleaning blade blade increases, the maximum wear rate Wlmax of the photoconductor in a low temperature and low humidity environment is preferably as small as possible while considering the wear of the cleaning blade. It can be seen that / Kcycle or less is more preferable.

The details of each abbreviation shown in the table will be described below.
[RCTM: Reactive charge transport material]
(Ib) -23: Exemplified compound (Ib) -23
(Ic) -3: Exemplified compound (Ic) -3
(Ic) -23: Exemplified compound (Ic) -23
(Ic) -53: Exemplified compound (Ic) -53
(Id) -28: Exemplified compound (Id) -28 (see the synthesis method below)
-(Id) -20: exemplary compound (Id) -20
(II) -50: Exemplified compound (II) -50
(II) -56: Exemplified compound (II) -56
(II) -181: Exemplary Compound II) -181
(II) -182: Exemplified compound (II) -182
(II) -172: Exemplified compound (II) -172
Compound (C): Compound represented by the following structural formula (C)

-Synthesis of Exemplified Compound (Id) -28-
To a 500 ml flask was added 22 g of the following compound (2), 33 g of potassium t-butoxy, 300 ml of tetrahydrofuran and 0.2 g of nitrobenzene, and a solution obtained by dissolving 25 g of 4-chloromethylstyrene in 150 ml of tetrahydrofuran while stirring under a nitrogen stream. It was dripped slowly. After completion of dropping, the mixture was heated to reflux for 4 hours, cooled, poured into water, and extracted with toluene. The toluene layer was washed thoroughly with water and then concentrated, and the resulting oil was purified by silica gel column chromatography to obtain 29 g of oily exemplified compound (Id) -28.

  Other exemplary compounds were also synthesized according to the above synthesis.

[CTM: Non-reactive charge transport material]
Compound (D): Compound represented by the following structural formula (D)

[RM: reactive material]
-Compound (B): Compound represented by the following structural formula (B)-Compound (E): Compound represented by the following structural formula (E)-Compound (F): Compound represented by the following structural formula (F)

DESCRIPTION OF SYMBOLS 1 ... Undercoat layer, 2 ... Charge generation layer, 3 ... Charge transport layer, 4 ... Conductive substrate, 5 ... Protective layer, 6 ... Single layer type photosensitive layer, 7A, 7B, 7C, 7 ... Electrophotographic photoreceptor, DESCRIPTION OF SYMBOLS 8 ... Charging device, 9 ... Exposure device, 11 ... Developing device, 13 ... Cleaning device, 131 ... Cleaning blade, 132 ... Lower seal, 133 ... Toner reservoir sheet, 40 ... Transfer device, 50 ... Intermediate transfer member, 100 ... Image formation Apparatus 120... Image forming apparatus 300 300 process cartridge

Claims (8)

A cured film of a composition comprising a conductive substrate and a photosensitive layer provided on the conductive substrate, and comprising two or more reactive charge transport materials, or a reactive charge transport material and a charge transport skeleton The surface of the electrophotographic photosensitive member is charged by charging means disposed in contact with or in close proximity to the surface of the electrophotographic photosensitive member having the outermost surface layer, which is a cured film of a composition containing a reactive material that does not react. Charging process,
An electrostatic latent image forming step of forming an electrostatic latent image on the surface of the charged electrophotographic photosensitive member;
A developing step of developing the electrostatic latent image formed on the surface of the electrophotographic photosensitive member with a developer including toner having toner particles and fatty acid metal salt particles to form a toner image;
A transfer step of transferring the toner image to the surface of the recording medium;
A cleaning step of cleaning the surface of the electrophotographic photosensitive member with a cleaning blade in contact with the surface of the electrophotographic photosensitive member;
Have
The content of the fatty acid metal salt particles with respect to the total mass of the toner is Rmf (mass%),
When an image including three types of image patterns having different image densities is repeatedly formed in a high-temperature and high-humidity environment, the average wear rate of the electrophotographic photosensitive member is Wh (nm / 1000 rotations), and the maximum wear of the electrophotographic photosensitive member is The rate is Whmax (nm / 1000 rotations), the minimum wear rate of the electrophotographic photosensitive member is Whmin (nm / 1000 rotations),
When an image including three types of image patterns having different image densities is repeatedly formed in a low-temperature and low-humidity environment, the average wear rate of the electrophotographic photoreceptor is Wl (nm / 1000 rotations), and the maximum wear rate of the electrophotographic photoreceptor is Is Wlmax (nm / 1000 rotations), and the minimum wear rate of the electrophotographic photosensitive member is Wlmin (nm / 1000 rotations),
Formula (A1), the following formula (B1), the following formula (B2), meets the following formula (C1) and the following formula (C2),
The image forming method, wherein the reactive charge transport material is a compound selected from chain polymerizable compounds represented by the following general formulas (I) and (II) .
Formula (A1): 0.01 <Rmf <0.20
Formula (B1): 0.005 <Rmf / Wh <5.000
Formula (B2): 0.002 <Rmf / Wl <1.000
Formula (C1): 1.0 <Whmax / Whmin <2.5
Formula (C2): 1.0 <Wlmax / Wlmin <2.5


[In general formula (I), F represents a charge transporting skeleton. L represents a divalent linking group containing two or more selected from the group consisting of an alkylene group, an alkenylene group, -C (= O)-, -N (R)-, -S-, and -O-. Show. R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. m represents an integer of 1 or more and 8 or less. ]


[In General Formula (II), F represents a charge transporting skeleton. L ′ represents a trivalent or tetravalent group derived from an alkane or alkene, and an alkylene group, alkenylene group, —C (═O) —, —N (R) —, —S—, and —O—. (N + 1) -valent linking groups containing two or more selected from the group consisting of: R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. m ′ represents an integer of 1 to 6. n represents an integer of 2 or more and 3 or less. ]   The image forming method according to claim 1, wherein the fatty acid metal salt particles are zinc stearate particles having a median diameter on a volume basis of 0.1 μm to 10.0 μm.   The image forming method according to claim 1, wherein the toner particles have a volume average particle size of 3.0 μm or more and 3.7 μm or less. The outermost surface layer is composed of a cured film of a composition comprising a reactive charge transporting material and a reactive material having no charge transporting skeleton;
The image according to any one of claims 1 to 3, wherein the reactive material is a chain polymerizable compound that does not have a charge transporting skeleton in the same molecule and has at least a chain polymerizable functional group. Forming method.   The image forming method according to any one of claims 1 to 4, wherein the reactive charge transport material is a chain polymerizable compound having at least a charge transport skeleton and a chain polymerizable functional group in the same molecule.   The image forming method according to claim 1, wherein the formula: 0.01 <Rmf <0.18 is satisfied. A cured film of a composition comprising a conductive substrate and a photosensitive layer provided on the conductive substrate, and comprising two or more reactive charge transport materials, or a reactive charge transport material and a charge transport skeleton A cured film of a composition containing a reactive material that does not, an electrophotographic photosensitive member having an outermost surface layer formed thereon,
A charging means disposed in contact with or in proximity to the surface of the electrophotographic photosensitive member to charge the surface of the electrophotographic photosensitive member;
An electrostatic latent image forming means for forming an electrostatic latent image on the surface of the charged electrophotographic photosensitive member;
Developing means for containing a developer containing toner having toner particles and fatty acid metal salt particles, and developing the electrostatic latent image formed on the surface of the electrophotographic photosensitive member with the developer to form a toner image When,
Transfer means for transferring the toner image to the surface of the recording medium;
Cleaning means having a cleaning blade that contacts the surface of the electrophotographic photosensitive member and cleans the surface of the electrophotographic photosensitive member;
With
The content of the fatty acid metal salt particles with respect to the total mass of the toner is Rmf (mass%),
When an image including three types of image patterns having different image densities is repeatedly formed in a high-temperature and high-humidity environment, the average wear rate of the electrophotographic photosensitive member is Wh (nm / 1000 rotations), and the maximum wear of the electrophotographic photosensitive member is The rate is Whmax (nm / 1000 rotations), the minimum wear rate of the electrophotographic photosensitive member is Whmin (nm / 1000 rotations),
When an image including three types of image patterns having different image densities is repeatedly formed in a low-temperature and low-humidity environment, the average wear rate of the electrophotographic photoreceptor is Wl (nm / 1000 rotations), and the maximum wear rate of the electrophotographic photoreceptor is Is Wlmax (nm / 1000 rotations), and the minimum wear rate of the electrophotographic photosensitive member is Wlmin (nm / 1000 rotations),
Formula (A1), the following formula (B1), the following formula (B2), meets the following formula (C1) and the following formula (C2),
An image forming apparatus, wherein the reactive charge transporting material is a compound selected from chain polymerizable compounds represented by the following general formulas (I) and (II) .
Formula (A1): 0.01 <Rmf <0.20
Formula (B1): 0.005 <Rmf / Wh <5.000
Formula (B2): 0.002 <Rmf / Wl <1.000
Formula (C1): 1.0 <Whmax / Whmin <2.5
Formula (C2): 1.0 <Wlmax / Wlmin <2.5


[In general formula (I), F represents a charge transporting skeleton. L represents a divalent linking group containing two or more selected from the group consisting of an alkylene group, an alkenylene group, -C (= O)-, -N (R)-, -S-, and -O-. Show. R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. m represents an integer of 1 or more and 8 or less. ]


[In General Formula (II), F represents a charge transporting skeleton. L ′ represents a trivalent or tetravalent group derived from an alkane or alkene, and an alkylene group, alkenylene group, —C (═O) —, —N (R) —, —S—, and —O—. (N + 1) -valent linking groups containing two or more selected from the group consisting of: R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. m ′ represents an integer of 1 to 6. n represents an integer of 2 or more and 3 or less. ] A cured film of a composition comprising a conductive substrate and a photosensitive layer provided on the conductive substrate, and comprising two or more reactive charge transport materials, or a reactive charge transport material and a charge transport skeleton A cured film of a composition containing a reactive material that does not, an electrophotographic photosensitive member having an outermost surface layer formed thereon,
A charging means disposed in contact with or in proximity to the surface of the electrophotographic photosensitive member to charge the surface of the electrophotographic photosensitive member;
Developing means for containing a developer containing toner having toner particles and fatty acid metal salt particles, and developing the electrostatic latent image formed on the surface of the electrophotographic photosensitive member with the developer to form a toner image When,
Cleaning means having a cleaning blade that contacts the surface of the electrophotographic photosensitive member and cleans the surface of the electrophotographic photosensitive member;
With
The content of the fatty acid metal salt particles with respect to the total mass of the toner is Rmf (mass%),
When an image including three types of image patterns having different image densities is repeatedly formed in a high-temperature and high-humidity environment, the average wear rate of the electrophotographic photosensitive member is Wh (nm / 1000 rotations), and the maximum wear of the electrophotographic photosensitive member is The rate is Whmax (nm / 1000 rotations), the minimum wear rate of the electrophotographic photosensitive member is Whmin (nm / 1000 rotations),
When an image including three types of image patterns having different image densities is repeatedly formed in a low-temperature and low-humidity environment, the average wear rate of the electrophotographic photoreceptor is Wl (nm / 1000 rotations), and the maximum wear rate of the electrophotographic photoreceptor is Is Wlmax (nm / 1000 rotations), and the minimum wear rate of the electrophotographic photosensitive member is Wlmin (nm / 1000 rotations),
The following formula (A1), the following formula (B1), the following formula (B2), the following formula (C1) and the following formula (C2) are satisfied,
The reactive charge transport material is a compound selected from chain polymerizable compounds represented by the following general formulas (I) and (II):
A process cartridge that can be attached to and detached from an image forming apparatus.
Formula (A1): 0.01 <Rmf <0.20
Formula (B1): 0.005 <Rmf / Wh <5.000
Formula (B2): 0.002 <Rmf / Wl <1.000
Formula (C1): 1.0 <Whmax / Whmin <2.5
Formula (C2): 1.0 <Wlmax / Wlmin <2.5


[In general formula (I), F represents a charge transporting skeleton. L represents a divalent linking group containing two or more selected from the group consisting of an alkylene group, an alkenylene group, -C (= O)-, -N (R)-, -S-, and -O-. Show. R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. m represents an integer of 1 or more and 8 or less. ]


[In General Formula (II), F represents a charge transporting skeleton. L ′ represents a trivalent or tetravalent group derived from an alkane or alkene, and an alkylene group, alkenylene group, —C (═O) —, —N (R) —, —S—, and —O—. (N + 1) -valent linking groups containing two or more selected from the group consisting of: R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. m ′ represents an integer of 1 to 6. n represents an integer of 2 or more and 3 or less. ]