JP6955331B2 - Manufacturing method of electrophotographic photosensitive member and electrophotographic photosensitive member - Google Patents

Description

The present invention relates to an electrophotographic photosensitive member and a method for producing an electrophotographic photosensitive member.

Abrasion resistance is required for an electrophotographic photosensitive member that is repeatedly used in an electrophotographic apparatus. However, since the amount of wear of the electrophotographic photosensitive member with improved wear resistance is small, surface deterioration and contamination due to durability are accumulated, and the frictional force with a contact member such as a cleaning blade is increased.
Therefore, the electrophotographic photosensitive member is required to have both wear resistance and low frictional force.

Patent Document 1 discloses a technique in which a polymerizable monomer and a cured product of a perfluoropolyether having a polymerizable functional group are contained in a surface layer. This is a technique for uniformly distributing perfluoropolyether in the surface layer by giving a polymerizable functional group to perfluoropolyether having high lubricity but low compatibility and binding it to the surface layer resin. .. The cured product of this perfluoropolyether is exposed to the surface due to wear of the surface layer to maintain low frictional force, while it is reduced by removal by cleaning. Therefore, in a usage environment where the amount of wear is small, the amount of surface exposure is insufficient, and low frictional force may not be maintained.

On the other hand, Patent Documents 2 and 3 disclose a technique of dispersing an oil having a fluoropolyether structure using a dispersant and allowing it to exist as a domain in a cured resin matrix. Since the oil having a fluoropolyether structure in this domain is not fixed to the resin matrix, it bleeds out from the inside of the layer to the surface when the amount of the outermost surface decreases. As a result, low frictional force can be maintained even when the amount of wear is small.

Japanese Unexamined Patent Publication No. 2012-128324 Japanese Unexamined Patent Publication No. 2013-231964 Japanese Unexamined Patent Publication No. 2015-028613

When applying the techniques of Patent Documents 2 and 3 to the surface layer of an electrophotographic photosensitive member, a charge transporting compound having no polymerizable functional group is added to the surface layer in order to improve the electrical characteristics of the electrophotographic photosensitive member. Then, the adhesion between the surface layer and the lower layer thereof has deteriorated.

An object of the present invention is to impair the adhesion between the surface layer and the lower layer thereof in an electrophotographic photosensitive member having a domain structure in which the surface layer contains an oil having a fluoropolyether structure in the cured resin matrix in the thickness direction thereof. To provide an electrophotographic photosensitive member having both wear resistance and low frictional force, and an electrophotographic apparatus and process cartridge having the electrophotographic photosensitive member, and a method for manufacturing the electrophotographic photosensitive member. Is to provide.

（ｒ ^１ は水素原子またはメチル基である。ｒ ^２ は炭素数８以上２０以下の直鎖あるいは分岐した無置換のアルキル基である。） An electrophotographic photosensitive member having a photosensitive layer and a surface layer, the surface layer having a matrix-domain structure in the thickness direction thereof, the domain containing an oil having a fluoropolyether structure, and the matrix. a cured product of the lower SL (a) or (B), it is an electrophotographic photosensitive member, wherein.
(A) A cured product of at least a charge-transporting compound having one polymerizable functional group, a compound having two or more polymerizable functional groups, and a compound represented by the following formula (1).
(B) A cured product of at least a charge-transporting compound having two polymerizable functional groups and a compound represented by the following formula (1).

(R ¹ is a hydrogen atom or a methyl group. ^{R 2} is a linear or branched alkyl group having 8 to 20 carbon atoms.)

Also, a manufacturing method of the electronic photosensitive member, a step of forming the surface layer, the (A) or the step of work made of mixed-solution (B), dispersion for the dispersion treatment in the mixture step process of a liquid, and applying the dispersion to form a coating film, and has the step of forming the surface layer by curing the coating film, at least, a process for producing an electrophotographic photosensitive member.

According to the present invention, in an electrophotographic photosensitive member in which the surface layer has an oil domain structure having a fluoropolyether structure in the cured resin matrix in the thickness direction thereof, the adhesion between the surface layer and the lower layer thereof is not impaired. It is possible to provide an electrophotographic photosensitive member having improved electrical characteristics and maintaining both wear resistance and low frictional force, and a method for producing the same.

It is a figure which shows an example of the layer structure of an electrophotographic photosensitive member. It is a schematic diagram of the surface layer cross section of an electrophotographic photosensitive member. It is a figure which shows an example of the schematic structure of the electrophotographic apparatus provided with the process cartridge which has an electrophotographic photosensitive member.

The electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member having a photosensitive layer and a surface layer, the surface layer having a matrix-domain structure in the thickness direction thereof, and the domain having a fluoropolyether structure. The matrix comprises a cured product of a composition containing an oil and a charge transporting compound having a polymerizable functional group, wherein the composition is the composition according to (A) or (B) below. do.
(A) A composition containing at least a charge-transporting compound having one polymerizable functional group and a compound having two or more polymerizable functional groups.
(B) A composition containing at least a charge-transporting compound having two polymerizable functional groups.

Hereinafter, the compound having a polymerizable functional group is also referred to as a “monomer”, and among them, the charge transporting compound having a polymerizable functional group is referred to as a “charge transporting monomer”. Further, an oil having a fluoropolyether structure is also referred to as "PFPE". Further, a composition containing a charge-transporting compound having a polymerizable functional group is also simply referred to as a "composition".

A feature of the present invention with respect to the prior art is that the resin forming the matrix contains a charge transporting monomer.
Patent Document 2 is a technique relating to an intermediate transcript, and does not describe a charge transport function.
Although Patent Document 3 describes an electrophotographic photosensitive member, its surface layer is a layer in which a metal oxide is contained in an organic component having no charge transport function. There was room for improvement in the electrical characteristics of this electrophotographic photosensitive member.
When the surface layer contained a charge-transporting compound having no polymerizable functional group in order to improve the electrical characteristics, the adhesion between the surface layer and the lower layer thereof was lowered. It is presumed that the reason for the decrease in adhesion is that one of the materials is unevenly distributed at the interface between the surface layer and the lower layer due to the problem of compatibility.
On the other hand, in the electrophotographic photosensitive member of the present invention, the adhesion between the surface layer and the lower layer thereof could be improved by using the charge transporting monomer as the charge transporting compound.

Each element will be described in detail below.
<Matrix-domain structure>
A schematic view of the surface layer cross section of the electrophotographic photosensitive member of the present invention is shown in FIG. The surface layer 201 has a matrix-domain structure in which the domain 203 is present in the matrix 202 in the thickness direction thereof. Here, the matrix 202 contains a cured product of the composition of (A) or (B), and the domain 203 contains a PFPE.

Since PFPE has a small surface free energy and low compatibility with the monomer in the composition, it easily migrates to the outermost surface side of the surface layer 201. When a mixed solution of PFPE and the composition is simply formed into a film, the PFPE is unevenly distributed on the outermost surface of the surface layer, so that the effect can be exhibited only at the very early stage of durable use. On the other hand, by performing a dispersion treatment on a mixed solution containing PFPE and the composition to disperse the PFPE in the composition, and applying and curing the PFPE, the domain 203 of the PFPE can be present in the matrix 202. .. As a result, the PFPE can be distributed evenly in the thickness direction of the surface layer 201 without being biased toward the outermost surface side of the surface layer 201. Further, unlike the technique of Patent Document 1, the PFPE in the domain 203 is not fixed to the matrix 202. As a result, when the outermost surface PFPE is removed by cleaning or the like, the PFPE can be surface-migrated (bleed out) from the domain 203 so as to reduce the concentration gradient, so that the low frictional force of the electrophotographic photosensitive member of the present invention can be maintained. ..

<Matrix structure>
The composition for obtaining a cured product forming the matrix 202 of the surface layer of the electrophotographic photosensitive member of the present invention contains a monomer having two or more polymerizable functional groups in order to obtain abrasion resistance of the surface layer. do. The monomer having two or more polymerizable functional groups may or may not have charge transporting property. However, at least one of the monomers contained in the composition is a charge transporting monomer. As a result, the electrical characteristics can be improved without impairing the adhesion between the surface layer and the lower layer thereof. The reason why the adhesion does not decrease is that the charge-transporting monomer has good compatibility with the components in the matrix 202, or because it is fixed to the matrix 202, the charge-transporting compound derived from the charge-transporting monomer in the matrix is unevenly distributed. I think it is because it is suppressed.

When the charge transporting monomer has one polymerizable functional group, the composition further contains a monomer having two or more polymerizable functional groups. This composition is the composition of (A). In the composition (A), the ratio of the contents of the charge-transporting monomer having one polymerizable functional group and the monomer having two or more polymerizable functional groups is 3: 10 to 20:10 in terms of mass ratio. Is preferable. If the ratio of the contents of the charge-transporting monomer having one polymerizable functional group is smaller than 3:10, the electrical characteristics of the surface layer cannot be sufficiently improved. Further, when the ratio of the contents of the charge-transporting monomer having one polymerizable functional group is larger than 20:10, there is a concern that the film strength of the surface layer may not be sufficient.
When the charge-transporting monomer has two or more polymerizable functional groups, the composition containing these is the composition (B). In the composition of (B), the content of the charge-transporting monomer having two or more polymerizable functional groups is preferably 30% by mass or more and 90% by mass or less in the composition of (B).

The composition of (A) or (B) may contain a monomer other than the above. For example, the composition (B) may further contain a compound having a polymerizable functional group and having no charge transporting property. Further, the composition (A) may contain a compound having one polymerizable functional group and having no charge transporting property.

<Monomer without charge transport>
The monomer having no charge transport property is a compound having no charge transport property among the compounds having a polymerizable functional group. As the monomer having no charge transport property, a monomer that forms a styrene resin, an acrylic resin, a methacrylic resin, an epoxy resin, a polyester resin, a polyether resin, a melamine resin, a urethane resin, or the like can be used. Of these, monomers that form acrylic resin and methacrylic resin are preferable. The number of polymerizable functional groups of the monomer having no charge transport property is not particularly limited. However, the composition (A) contains at least one monomer having two or more polymerizable functional groups. Further, as the monomer having no charge transporting property, a monomer having the same polymerizable functional group as the charge transporting monomer contained in the same composition is preferable.

For example, the monomer having no charge transport property is not limited to these, but is not limited to these, pentaerythritol triacrylate, pentaerythritol tetraacrylate, ditrimethylolpropanetetraacrylate, dipentaerythritol hexaacrylate, alkyl acrylate, benzyl acrylate, phenyl acrylate. , Ethylene glycol diacrylate, bisphenol A diacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, ditrimethylolpropanetetramethacrylate, dipentaerythritol hexamethacrylate, alkyl methacrylate, benzyl methacrylate, phenylmethacrylate, ethylene glycol dimethacrylate, bisphenol A methacrylate Etc. can be used.

When a compound represented by the following formula (1) is used as a monomer having no charge transport property, the dispersion of PFPE in the dispersion liquid in which the mixed liquid of PFPE and the composition is dispersed is stable, so that the compound is dispersed in the dispersion step. The strength can be relaxed and the dispersion time can be shortened. Further, when a dispersant is used, the required amount of the dispersant can be suppressed, so that the film strength of the film obtained by curing the coating film of the dispersion liquid can be improved.

式（１）中、ｒ^１は水素原子またはメチル基である。ｒ^２は炭素数８以上２０以下の直鎖あるいは分岐した無置換のアルキル基である。 The reason why the dispersion of PFPE is stable is considered as follows. First, when the dispersion liquid contains a compound represented by the formula (1), the composition is at least a compound represented by the formula (1) (a monomer having one functional group), a monomer having two or more polymerizable functional groups, and the like. Contains three components of PFPE. The compound represented by the formula (1) contains a vinyl ester group and a long-chain alkyl group. When the solubility parameter of each functional group portion is calculated, the long-chain alkyl group has a higher affinity with PFPE, and the vinyl ester group has a higher affinity with a monomer having two or more polymerizable functional groups. That is, the compound represented by the formula (1) is expected to behave like a dispersant in the dispersion liquid.

In formula (1), r ¹ is a hydrogen atom or a methyl group. r ² is a linear or branched unsubstituted alkyl group having 8 or more and 20 or less carbon atoms.

Equation (1) the number of carbon atoms is small in the r ² in the compound represented by, or if too much, dispersion of the PFPE is difficult to obtain the effect of stabilizing in the dispersion. Therefore, although the number of carbon atoms of r ² is preferably 8 to 20, even 7 or less or 21 or more, the use of selection and dispersants manufacturing conditions, it is possible to stabilize the dispersion of the PFPE in the dispersion Therefore, a matrix-domain structure can be formed.

The compound represented by the formula (1) may contain only one kind in the surface layer, or may contain two or more kinds. Specific examples of the compound represented by the formula (1) include the compounds shown in Table A below.

<Monomer with charge transport property>
The charge-transporting monomer (charge-transporting monomer) is a compound having a charge-transporting skeleton and a polymerizable functional group in the same molecule. Examples of the skeleton having charge transporting property include a skeleton having hole transporting property such as hydrazone, carbazole, and triphenylamine. Examples of the polymerizable functional group include a hydroxyl group, a vinyl group, an acryloyloxy group, a methacryloyloxy group, a styryl group, a vinyl ether group, and an allyl group.

Examples of the charge transporting monomer include known compounds described in JP-A-2000-066425, JP-A-2007-241140, and JP-A-2010-21103. Of these, a charge-transporting monomer having an acryloyloxy group or a methacryloyloxy group as the polymerizable functional group is preferable.

式（２）中、Ａｒ^１〜Ａｒ^３は置換基を有してもよいアリール基を示す。Ａｒ^１〜Ａｒ^３のうち少なくとも１つが重合性官能基を有し、Ａｒ^１〜Ａｒ^３のうち少なくとも１つが式（４）で示される置換基または式（５）で示される置換基を有する。ただし、置換基として該重合性官能基を有するアリール基は、式（４）または式（５）で示される置換基を有さない。

式（３）中、Ａｒ^４〜Ａｒ^７は置換基を有してもよいアリール基を示し、Ａｒ^８およびＡｒ^９は置換基を有してもよいアリーレン基を示す。Ａｒ^４〜Ａｒ^９のうち少なくとも１つが重合性官能基を有し、Ａｒ^４〜Ａｒ^９のうち少なくとも１つが式（４）で示される置換基または式（５）で示される置換基を有する。ただし、置換基として該重合性官能基を有するアリール基およびアリーレン基は、式（４）または式（５）で示される置換基を有さない。 When a compound represented by the following formula (2) or formula (3) is used as the charge transporting monomer, the dispersion of PFPE in the dispersion liquid in which the mixed solution of PFPE and the composition is dispersed is stable.

In the formula (2), Ar ^{1 to} Ar ³ represent an aryl group which may have a substituent. At ^{least one of Ar 1 to} Ar ³ has a polymerizable functional group, and ^{at least one of Ar 1 to} Ar ³ has a substituent represented by the formula (4) or a substituent represented by the formula (5). However, the aryl group having the polymerizable functional group as a substituent does not have the substituent represented by the formula (4) or the formula (5).

In formula (3), Ar ^{4 to} Ar ⁷ indicate an aryl group which may have a substituent, and Ar ⁸ and Ar ⁹ indicate an arylene group which may have a substituent. At ^{least one of Ar 4 to} Ar ⁹ has a polymerizable functional group, and ^{at least one of Ar 4 to} Ar ⁹ has a substituent represented by the formula (4) or a substituent represented by the formula (5). However, the aryl group and the arylene group having the polymerizable functional group as the substituent do not have the substituent represented by the formula (4) or the formula (5).

式（４）中、ｐは０または１を示す。ｑは０〜２の整数を示す。Ｒ^１およびＲ^２はそれぞれ水素原子またはメチル基を示し、Ｒ^３は炭素数７以下のパーフルオロアルキル基を示す。

式（５）中、Ａｒ^１０は置換基を有してもよいアリール基からｕ個の水素原子を除いた基を示す。ｓは０または１を示す。ｔは０〜２の整数を示す。ｕは１以上の整数を示す。ｓ＋ｔ≧１であり、Ｒ^４およびＲ^５はそれぞれ水素原子またはメチル基を示し、Ｒ^６は炭素数７以下のパーフルオロアルキル基を示す。

In formula (4), p represents 0 or 1. q indicates an integer of 0 to 2. R ¹ and R ² represent a hydrogen atom or a methyl group, respectively, and R ³ represents a perfluoroalkyl group having 7 or less carbon atoms.

In formula (5), Ar ¹⁰ represents a group obtained by removing u hydrogen atoms from an aryl group which may have a substituent. s indicates 0 or 1. t indicates an integer of 0 to 2. u represents an integer of 1 or more. s + t ≧ 1, R ⁴ and R ⁵ each represent a hydrogen atom or a methyl group, and R ⁶ represents a perfluoroalkyl group having 7 or less carbon atoms.

Examples of the polymerizable functional group of the compounds represented by the above formulas (2) and (3) include a vinyl group, an acryloyloxy group, a methacryloyloxy group, a styryl group, a vinyl ether group, an allyl group and the like. Of these, acryloyloxy groups and methacryloyloxy groups are preferable.

Specific examples of the aryl groups of Ar ^{1 to} Ar ⁷ include groups obtained by removing one hydrogen atom from benzene, naphthalene, fluorene, phenanthrene, anthracene, pyrene, biphenyl, terphenyl, stilbene and the like. Examples of the arylene groups of Ar ^{8 to Ar 10} include groups obtained by removing two hydrogen atoms from benzene, naphthalene, fluorene, phenanthrene, anthracene, pyrene, biphenyl, terphenyl, stilbene and the like.

Specific examples of the substituents of Ar ^{1 to} Ar ¹⁰ include alkyl groups such as methyl group, ethyl group, n-propyl group, isopropyl group, t-butyl group and isobutyl group, methoxy group, ethoxy group and n-propoxy group. Examples thereof include an alkoxy group such as an isopropoxy group, a t-butoxy group and an isobutoxy group.

The compounds represented by the above formulas (2) and (3) preferably have two or more substituents represented by the formula (4) or the substituents represented by the formula (5).

R ³ and R ⁶ are preferably a fluoroalkyl group having 3 or more carbon atoms and 7 or less carbon atoms, and more preferably a perfluoroalkyl group.

When forming the surface layer of the electrophotographic photosensitive member, the compounds represented by the above formulas (2) and (3) may be used alone or in combination of two or more.

The compounds represented by the above formulas (2) and (3) used in the present invention are synthesized by using, for example, the synthesis methods described in JP-A-2000-066425 and JP-A-2007-11006. Can be done.

Specific examples (exemplified compounds) of the compounds represented by the above formulas (2) and (3) are given below, but the present invention is not limited thereto.

Among these, Exemplified Compounds (2-35), (2-37), (2-39), (2-40), (2-41), (2-42), (3-8), (3) -9) and (3-10) are preferable.

<Oil with fluoropolyether structure>
The oil (PFPE) having a fluoropolyether structure in the present invention refers to an oligomer or polymer having a perfluoroalkylene ether as a repeating unit. Repeating units for perfluoroalkylene ether include repeating units for perfluoromethylene ether, perfluoroethylene ether, and perfluoropropylene ether.

Among them, it is preferable that the perfluoropolyether has a repeating structural unit represented by the following formula (a) or a repeating structural unit represented by the following formula (b).

Specific examples of PFPE include Demnam of Daikin Industries, Critex of DuPont, and Fomblin of Solvaisolexis.

When the PFPE has either the repeating structural unit represented by the formula (a) or the repeating structural unit represented by the formula (b), the number of repetitions m of the repeating structural unit represented by the formula (a) and the formula (b). ), The number of repetitions n of the repeating structural unit is preferably 0 ≦ m ≦ 100 and 0 ≦ n ≦ 100, respectively. Further, when the PFPE has both the repeating structural unit represented by the formula (a) and the repeating structural unit represented by the formula (b), it is preferable that m + n ≧ 1, and these structures are block copolymer structures. Or a random copolymer structure may be formed.

The weight average molecular weight Mw of PFPE present in the surface layer is preferably 100 or more and 9000 or less in order for PFPE to migrate (bleed out) from the domain to the outermost surface.

The terminal group of PFPE may have a non-polymerizable functional group that does not react with the monomer forming the matrix, or may have a polymerizable functional group that reacts with the monomer. Even when PFPE has a polymerizable functional group, a PFPE domain can be formed by selecting a formulation or dispersion treatment, and since unreacted PFPE exists inside the domain, the transfer of PFPE to the outermost surface ( Bleed out) is done.

For example, when the matrix is formed by polymerization of a monomer, examples of the non-polymerizable functional group that does not undergo an addition reaction with the monomer include a trifluoromethyl group or a methyl group. Examples of PFPEs having such non-polymerizable functional groups include Fluorolink D4000 and Fomblin Z15 manufactured by Solvay Specialty Polymers Japan Co., Ltd., and Demnum S-20, S-65 and S200 manufactured by Daikin Industries, Ltd. Examples of the polymerizable functional group that undergoes an addition reaction with the monomer include a hydroxyl group, an acrylic group, a methacryl group, and an oxylanyl group. Examples of the PFPE having an acrylic group or a methacrylic group include Fluorolink D10H, MD500, MD700, 5101X, 5113X and AD1700 manufactured by Solvay Specialty Polymers Japan Co., Ltd. In addition, there are Optool DAC manufactured by Daikin Industries, Ltd. and Fluorolink S10 containing a silane group manufactured by Solvay Specialty Polymers Japan Co., Ltd. Further, PFPE which can be prepared by the synthesis method described in JP-A-2015-28613 can be used.

The content of PFPE is preferably 10% by mass or more and 70% by mass or less with respect to the mass of the total solid content of the surface layer.

<Dispersant>
The surface layer may contain a dispersant. The dispersant can make the dispersed state of PFPE more stable in the dispersion liquid obtained by dispersing the mixed liquid of PFPE and the composition. The dispersant is a compound having an affinity for a fluoroalkyl group and a polymerizable functional group. The dispersant preferably contains at least one of the following copolymers (i) and (ii).
(I) A block copolymer obtained by copolymerizing a vinyl monomer having a fluoroalkyl group with acrylate or methacrylate.
(Ii) A comb-type graft copolymer obtained by copolymerizing fluoroalkyl acrylate or fluoroalkyl methacrylate with a methacrylate macromonomer having polymethyl methacrylate in the side chain.

Examples of the block copolymer (i) include Modipers F200, F210, F2020, F600, and FT-600 manufactured by NOF CORPORATION.
Examples of the comb-type graft copolymer of (ii) include Aron GF-150, GF-300, GF-400, and GF-420 manufactured by Toagosei Corporation.

As described above, the dispersant is a copolymer of acrylate and / or methacrylate having a fluoroalkyl group, that is, a thermoplastic resin, and has low strength as a resin. Therefore, the content of the dispersant in the surface layer is preferably as small as possible to form the matrix-domain structure, and is preferably 20% by mass or less with respect to the total mass of the solid content in the surface layer. For example, by using the compounds represented by the above formulas (1), (2), and (3), the required amount of dispersant can be reduced.

<Manufacturing method of surface layer>
The method for producing the surface layer is as follows. First, the composition (A) or (B), the solvent, and the PFPE, and if necessary, the dispersant are mixed to obtain a mixed solution. The mixed solution is dispersed to obtain a dispersion. This dispersion is applied onto the photosensitive layer by a coating method such as bar coating, spray coating, or dip coating to form a coating film. A surface layer is formed by curing the monomer in the obtained coating film.

The dispersion treatment is a treatment for allowing PFPE to exist as particles in the mixed liquid to form a dispersion liquid. When the surface layer is formed using the dispersion liquid thus treated, a surface layer having a desired matrix-domain structure is obtained. For dispersion processing, colloid mills that utilize narrow gaps between disks, high-speed rotary shear type stirrers that utilize narrow gaps between rotary blades and containers, high-pressure injection dispersers, ultrasonic dispersers, ball mills, sand mills, etc. Can be used. Distributed processing may be performed by sequentially using a plurality of devices in which these are combined or a plurality of devices.

The dispersed liquid may not be able to maintain the dispersed state over time depending on the composition of the liquid and the storage state. A dispersant or the like may be used to stabilize the dispersion. Further, even if the dispersion liquid is unstable, the time from the dispersion treatment to the completion of the surface layer formation is shortened, and the coating film is formed and cured while the dispersed state is maintained, thereby forming a matrix-domain structure. A surface layer having the above can be formed.

The dispersion may contain a polymerization initiator. Examples of the polymerization initiator include radical polymerizable initiators such as alkylphenone and acylphosphine oxide, cationic polymerization initiators such as aromatic sulfonium salts, and nifedipine anionic polymerization initiators. Specific examples thereof include the Irgacure series (manufactured by BASF) and the SP series (manufactured by ADEKA).

Examples of the reaction for curing the monomer include radical polymerization and ionic polymerization. Curing can be performed by activating the polymerization initiator with heat, light (ultraviolet rays, etc.), or radiation (electron rays, etc.).

Among the curing methods, curing with an electron beam is preferable. The composition ratio of the coating film changes as the solvent volatilizes due to the application of heat, and the desired dispersed state may not be maintained. Therefore, a curing method that can be cured in a short time with a small temperature rise, such as curing by an electron beam, is preferable. From this point of view, the amount of the dispersant can be relatively reduced as compared with other curing methods, and as a result, the wear resistance can be improved.

When irradiating an electron beam, examples of the accelerator include a scanning type, an electrocurtain type, a broad beam type, a pulse type, and a laminar type. Regarding the output of the electron beam, from the viewpoint of suppressing the deterioration of material properties due to the electron beam without impairing the polymerization efficiency, the acceleration voltage of the electron beam is 120 kV or less, and the electron beam absorbed dose on the coating surface is 1 kGy or more and 50 kGy or less. It is preferable to have. Further, for the purpose of suppressing the polymerization inhibitory action by oxygen, it is preferable that the monomer is cured in an inert gas atmosphere. Examples of the inert gas include nitrogen, argon and helium. After the electron beam irradiation, it may be heated if necessary.

<Structure of electrophotographic photosensitive member>
The electrophotographic photosensitive member of the present invention has a support, a charge generation layer formed on the support, a charge transport layer formed on the charge generation layer, and a protection formed on the charge transport layer if necessary. Has a layer.

FIG. 1 is a diagram showing an example of a layer structure of an electrophotographic photosensitive member. In FIG. 1, the electrophotographic photosensitive member has a support 101, a charge generation layer 102, a charge transport layer 103, and a protective layer 104. When the electrophotographic photosensitive member has the protective layer 104, the protective layer 104 becomes the surface layer, and when the electrophotographic photosensitive member does not have the protective layer 104, the charge transport layer 103 becomes the surface layer. The photosensitive layer is composed of a charge generating layer 102 and a charge transporting layer 103, and when the electrophotographic photosensitive member does not provide the protective layer 104, the charge transporting layer 103 is a part of the photosensitive layer and at the same time a surface layer. The surface layer has a matrix-domain structure in its thickness direction, the domain contains an oil having a fluoropolyether structure, and the matrix contains a cured product of a composition containing a charge-transporting monomer. Further, if necessary, a conductive layer or an undercoat layer described later may be provided between the support 101 and the photosensitive layer (charge generation layer 102 and charge transport layer 103).

As the support used in the electrophotographic photosensitive member of the present invention, a support having conductivity (conductive support) is preferable. For example, a support made of a metal or alloy such as aluminum, an aluminum alloy, or stainless steel can be mentioned. In the case of a support made of aluminum or an aluminum alloy, an ED tube, an EI tube, or a support obtained by cutting, electrolytically compound polishing, wet or dry honing treatment of these can also be used. Further, a thin film of a conductive material such as aluminum, an aluminum alloy, and an indium-tin oxide alloy may be formed on the metal or resin and used as a support.
The surface of the support may be subjected to a cutting treatment, a roughening treatment, an alumite treatment, or the like.
Further, a support formed by impregnating a resin or the like with conductive particles such as carbon black, tin oxide particles, titanium oxide particles, and silver particles, or a support made of a conductive resin can also be used.

A conductive layer containing conductive particles and a binder resin may be provided between the support and the charge generation layer or the undercoat layer described later.
The conductive layer is formed by applying a coating liquid for a conductive layer obtained by dispersing conductive particles together with a binder resin and a solvent to form a coating film, and drying and / or curing the obtained coating film. can do.

Examples of the conductive particles used in the conductive layer include carbon black, acetylene black, metal particles such as aluminum, nickel, iron, nichrome, copper, zinc, and silver, and metal oxides such as tin oxide and ITO. Particles and the like.

Examples of the resin used for the conductive layer include acrylic resin, alkyd resin, epoxy resin, phenol resin, butyral resin, polyacetal, polyurethane, polyester, polycarbonate, and melamine resin.

Examples of the solvent used in the coating liquid for the conductive layer include an ether solvent, an alcohol solvent, a ketone solvent, and an aromatic hydrocarbon solvent.
The film thickness of the conductive layer is preferably 0.2 μm or more and 40 μm or less, and more preferably 5 μm or more and 40 μm or less.

An undercoat layer may be provided between the support or the conductive layer and the charge generation layer.
The undercoat layer can be formed by applying a coating liquid for an undercoat layer containing a resin to form a coating film, and drying or curing the obtained coating film.

Examples of the resin used for the undercoat layer include polyacrylic acid, methyl cellulose, ethyl cellulose, polyamide, polyimide, polyamide-imide, polyamic acid, melamine resin, epoxy resin, and polyurethane.

The undercoat layer may also contain the above-mentioned conductive particles, semi-conductive particles, electron transporting substances, and electron accepting substances.

Examples of the solvent used in the coating liquid for the undercoat layer include ether solvents, alcohol solvents, ketone solvents, aromatic hydrocarbon solvents and the like.
The film thickness of the undercoat layer is preferably 0.05 μm or more and 40 μm or less, and more preferably 0.4 μm or more and 20 μm or less.

A charge generation layer is formed on the support, the conductive layer, or the undercoat layer.
The charge generating layer is formed by applying a coating liquid for a charge generating layer obtained by dispersing a charge generating substance together with a binder resin and a solvent to form a coating film, and drying the obtained coating film. Can be done. Further, the charge generation layer may be a vapor-deposited film of a charge generation substance.

Examples of the charge generating substance used in the charge generating layer include pyrylium, thiapyrylium dyes, phthalocyanine compounds, anthanthron pigments, dibenzpyrene quinone pigments, pyranthron pigments, azo pigments, indigo pigments, quinacridone pigments, and quinocyanine pigments. .. Among these, a phthalocyanine compound is preferable, and gallium phthalocyanine is more preferable. Furthermore, from the viewpoint of high sensitivity, hydroxygallium phthalocyanine is preferable, and among them, strong peaks at 7.4 ° ± 0.3 ° and 28.2 ° ± 0.3 ° of Bragg angle 2θ in CuKα characteristic X-ray diffraction. Hydroxygallium phthalocyanine crystals having the above are preferable.

Examples of the binder resin used for the charge generation layer include polycarbonate, polyester, butyral resin, polyvinyl acetal, acrylic resin, vinyl acetate resin, and urea resin. Of these, butyral resin is preferable. Only one kind of these resins may be used, or two or more kinds thereof may be used in combination as a mixture or a copolymer.

In the charge generating layer, the ratio of the charge generating substance to the binding resin is preferably 0.3 parts by mass or more and 4 parts by mass or less of the binding resin with respect to 1 part by mass of the charge generating substance.

In addition, examples of the dispersion treatment method include a method using a homogenizer, ultrasonic waves, a ball mill, a sand mill, an attritor, and a roll mill.

Examples of the solvent used in the coating liquid for the charge generation layer include alcohol-based solvents, sulfoxide-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents.
The film thickness of the charge generation layer is preferably 0.01 μm or more and 5 μm or less, and more preferably 0.1 μm or more and 1 μm or less.

Further, various sensitizers, antioxidants, ultraviolet absorbers, and plasticizers can be added to the charge generation layer, if necessary.

A charge transport layer is formed on the charge generation layer.
The charge transport layer is formed by applying a coating liquid for a charge transport layer obtained by dissolving a charge transport substance and a binder resin in a solvent to form a coating film, and drying the obtained coating film. Can be done.

When the electrophotographic photosensitive member of the present invention is provided with a protective layer, the following charge transporting substances, binding substances, and solvents can be used for the charge transporting layer.

Examples of the charge transporting substance include a triarylamine compound, a hydrazone compound, a stillben compound, a pyrazoline compound, an oxazole compound, a thiazole compound, and a triarylmethane compound.

Examples of the binder resin include polyvinyl butyral, polyarylate, polycarbonate, polyester, phenoxy resin, polyvinyl acetate, acrylic resin, polyacrylamide, polyamide, polyvinylpyridine, cellulose resin, urethane resin, epoxy resin, agarose resin, and cellulose resin. , Casein, polyvinyl alcohol, polyvinylpyrrolidone and the like. Only one kind of these resins may be used, or two or more kinds thereof may be used in combination as a mixture or a copolymer.

The ratio of the charge-transporting substance is preferably 30% by mass or more and 70% by mass or less with respect to the total mass of the charge-transporting layer.

Examples of the solvent include ether solvents, alcohol solvents, ketone solvents, and aromatic hydrocarbon solvents. The film thickness of the charge transport layer is preferably 5 μm or more and 40 μm or less.

The surface layer of the electrophotographic photosensitive member of the present invention is formed by using the above-mentioned PFPE and composition according to the above-mentioned method for producing the surface layer. When the electrophotographic photosensitive member is not provided with the protective layer, the surface layer is the charge transport layer, and when the protective layer is provided, the surface layer is the protective layer.

Various additives may be added to the surface layer as needed. Examples of the additive include the above-mentioned dispersant and a polymerization control agent such as a polymerization reaction initiator and a polymerization reaction terminator. Examples thereof include deterioration inhibitors such as antioxidants and ultraviolet absorbers, fillers such as metal oxides, and leveling agents such as silicone oil.

Solvents used for the coating liquid for the surface layer include alcohol solvents such as methanol, ethanol and propanol, ketone solvents such as acetone, methyl ethyl ketone and cyclohexanone, ester solvents such as ethyl acetate and butyl acetate, and tetrahydrofuran and dioxane. Ether solvent, halogen solvent such as 1,1,2,2,3,3,4-heptafluorocyclopentane, dichloromethane, dichloroethane, chlorobenzene, aromatic solvent such as benzene, toluene, xylene, methyl cellosolve, ethyl Examples thereof include cellosolve-based solvents such as cellosolve. Only one of these solvents may be used, or two or more of these solvents may be mixed and used.

When the electrophotographic photosensitive member of the present invention is provided with a protective layer, the film thickness of the protective layer as a surface layer is preferably 2 μm or more and 20 μm or less.
When the electrophotographic photosensitive member of the present invention is not provided with the protective layer, the film thickness of the charge transport layer as the surface layer is preferably 5 μm or more and 40 μm or less.

When applying the coating liquid of each of the above layers, for example, a coating method such as a dipping coating method (dipping method), a spray coating method, a spinner coating method, a bead coating method, a blade coating method, or a beam coating method can be used.

<Outline of electrophotographic equipment>
FIG. 3 shows an example of a schematic configuration of an electrophotographic apparatus including a process cartridge having an electrophotographic photosensitive member.
In FIG. 3, the cylindrical electrophotographic photosensitive member 1 is rotationally driven with a predetermined peripheral speed (process speed) in the direction of an arrow about a shaft 2. The surface (peripheral surface) of the electrophotographic photosensitive member 1 is positively or negatively charged by the charging means (primary charging means) 3 in the rotation process. Next, the surface of the electrophotographic photosensitive member 1 is irradiated with exposure light (image exposure light) 4 output from the exposure means (image exposure means) (not shown). The exposure light 4 is intensity-modulated corresponding to the time-series electric digital image signal of the target image information. Examples of the exposure means include slit exposure and laser beam scanning exposure. In this way, an electrostatic latent image corresponding to the target image information is formed on the surface of the electrophotographic photosensitive member 1.

The electrostatic latent image formed on the surface of the electrophotographic photosensitive member 1 is then developed (regular development or reverse development) with the toner contained in the developing means 5 to form a toner image. The toner image formed on the surface of the electrophotographic photosensitive member 1 is transferred to the transfer material 7 by the transfer means 6. Here, when the transfer material 7 is paper, it is taken out from the paper feed unit (not shown) in synchronization with the rotation of the electrophotographic photosensitive member 1 and fed between the electrophotographic photosensitive member 1 and the transfer means 6. Will be done. Further, a bias voltage having a polarity opposite to the charge held by the toner is applied to the transfer means 6 from a bias power source (not shown). Further, the transfer means 6 may be an intermediate transfer type transfer means having a primary transfer member, an intermediate transfer body and a secondary transfer member.

The transfer material 7 to which the toner image is transferred is separated from the surface of the electrophotographic photosensitive member 1, transported to the fixing means 8, and subjected to the fixing treatment of the toner image, so that the transfer material 7 is electron as an image forming product (print, copy). It is printed out of the photographic device.

The surface of the electrophotographic photosensitive member 1 after the toner image transfer is cleaned by the cleaning means 9, and deposits such as transfer residual toner are removed. The transfer residual toner can also be recovered by the developing means 5 or the like. Further, if necessary, the surface of the electrophotographic photosensitive member 1 is subjected to static elimination treatment by irradiation with pre-exposure light 10 from a pre-exposure means (not shown), and then repeatedly used for image formation. When the charging means 3 is a contact charging means using a charging roller or the like, the pre-exposure means is not always necessary.

Among the components selected from the electrophotographic photosensitive member 1, the charging means 3, the developing means 5, the transferring means 6, the cleaning means 9, and the like, a plurality of components may be housed in a container to form the process cartridge 11. Further, the process cartridge 11 may be detachably attached to and detached from the main body of the electrophotographic apparatus. For example, the electrophotographic photosensitive member 1 and at least one means selected from the group consisting of the charging means 3, the developing means 5, the transferring means 6, and the cleaning means 9 are integrally supported to form a cartridge. Then, the process cartridge 11 that can be attached to and detached from the electrophotographic apparatus main body can be formed by using the guiding means 12 such as the rail of the electrophotographic apparatus main body.

Hereinafter, a more detailed description will be given with reference to specific examples. In addition, "part" in an Example means "mass part". Further, the electrophotographic photosensitive member is also hereinafter simply referred to as a “photoreceptor”.

<Manufacturing example of electrophotographic photosensitive member>
-Support A cylindrical aluminum cylinder having a diameter of 29.92 mm, a length of 357.5 mm, and a thickness of 0.7 mm was used as the support.

-Undercoat layer Next, 100 parts of zinc oxide particles (specific surface area: 19 m ² / g, powder resistance: 4.7 × 10 ⁶ Ω · cm) as metal oxides were stirred and mixed with 500 parts of toluene. 0.8 part of a silane coupling agent (compound name: N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, trade name: KBM602, manufactured by Shin-Etsu Chemical Co., Ltd.) was added thereto for 6 hours. Stirred. Then, toluene was distilled off under reduced pressure, and the mixture was heated and dried at 140 ° C. for 6 hours to obtain surface-treated zinc oxide particles.

Next, as a polyol resin, 15 parts of butyral resin (trade name: BM-1, manufactured by Sekisui Chemical Co., Ltd.) and 15 parts of blocked isocyanate (trade name: Sumijour 3175, manufactured by Sumitomo Bavarian Urethane Co., Ltd.) were added to a mixed solution. It was dissolved. The mixed solution is a mixture of 73.5 parts of methyl ethyl ketone and 73.5 parts of 1-butanol.

80.8 parts of the surface-treated zinc oxide particles and 0.4 parts of 2,3,4-trihydroxybenzophenone (manufactured by Tokyo Chemical Industry Co., Ltd.) are added to this solution, and this is added to a glass having a diameter of 0.8 mm. The mixture was dispersed in a sand mill using beads in an atmosphere of 23 ± 3 ° C. for 3 hours. After dispersion, 0.01 part of silicone oil (trade name: SH28PA, manufactured by Toray Dow Corning Silicone), crosslinked polymethyl methacrylate (PMMA) particles (trade name: TECHPOLYMER SSX-103, manufactured by Sekisui Plastics Co., Ltd.) , Average primary particle size 3.1 μm) 5.6 parts was added and stirred to prepare a coating solution for the undercoat layer.
The coating liquid for the undercoat layer was immersed and coated on the support, and the obtained coating film was dried at 160 ° C. for 40 minutes to form an undercoat layer having a film thickness of 18 μm.

-Charge generation layer Next, the following four substances were placed in a sand mill using glass beads having a diameter of 1 mm, dispersed for 4 hours, and then 700 parts of ethyl acetate was added to prepare a coating solution for the charge generation layer. ..
-Crystal hydroxygallium phthalocyanine crystal having strong peaks at 7.4 ° and 28.2 ° at Bragg angle 2θ ± 0.2 ° in CuKα characteristic X-ray diffraction (charge generator)
・ ・ ・ 20 copies ・ Polyvinyl butyral (trade name: Eslek BX-1, manufactured by Sekisui Chemical Co., Ltd.)
・ ・ ・ 10 parts ・ Cyclohexanone ・ ・ ・ 600 parts By dipping and coating this coating liquid for the charge generation layer on the undercoat layer and drying the obtained coating film at 80 ° C. for 15 minutes, the film thickness is 0.18 μm. Formed a charge generation layer.

この電荷輸送層用塗布液を電荷発生層上に浸漬塗布し、得られた塗膜を３０分間１１０℃で乾燥させることによって、膜厚１８μｍの電荷輸送層を形成した。 -Charge transport layer Next, a coating liquid for a charge transport layer was prepared by dissolving the following five substances in a mixed solvent of 600 parts of xylene and 200 parts of dimethoxymethane.
・ Compound represented by formula (6) (charge transporting substance) ・ ・ ・ 30 parts ・ Compound represented by formula (7) (charge transporting substance) ・ ・ ・ 60 parts ・ Compound represented by formula (8) (charge transporting substance) Material) ・ ・ ・ 10 parts ・ Polycarbonate resin (trade name: Upiron Z400, manufactured by Mitsubishi Engineering Plastics Co., Ltd., bisphenol Z type polycarbonate) ・ ・ ・ 100 parts ・ Polycarbonate represented by formula (9) (viscosity average molecular weight) Mv: 20000)
・ ・ ・ 0.02 copies

The coating liquid for the charge transport layer was immersed and coated on the charge generation layer, and the obtained coating film was dried at 110 ° C. for 30 minutes to form a charge transport layer having a film thickness of 18 μm.

-Protective layer Next, a mixed solvent of 100 parts of 1,1,2,2,3,3,4-heptafluorocyclopentane (trade name: Zeorora H, manufactured by Nippon Zeon Corporation) and 100 parts of 1-propanol was added. Created. The compounds shown in Table 1 selected from the following compound group were added to this mixed solvent, and the mixture was stirred for 12 hours to prepare a mixed solution.

電荷輸送性モノマー
・式（１０）で示される化合物
・式（１１）で示される化合物
・化合物（２−３７）
・化合物（２−４１）

電荷輸送性物質
・式（６）で示される化合物 Monomer with no charge transport property-Pentaerythritol tetraacrylate manufactured by Shin-Nakamura Chemical Industry Co., Ltd .; A-TMMT
-Compound (1-2)
-Compound (1-14)
-Compound represented by the formula (12)

Charge-transporting monomer-Compound represented by formula (10) -Compound represented by formula (11) -Compound (2-37)
-Compound (2-41)

Charge transporting substance ・ Compound represented by formula (6)

PFPE
・ Fluorolink MD500 manufactured by Solvay Specialty Polymers Japan Co., Ltd.
・ Fluorolink MD700 manufactured by Solvay Specialty Polymers Japan Co., Ltd.
・ Fluorolink AD1700 manufactured by Solvay Specialty Polymers Japan Co., Ltd.

Dispersant, Toagosei Co., Ltd. Aron GF300
・ Aron GF400 manufactured by Toagosei Co., Ltd.
・ Aron GF420 manufactured by Toagosei Co., Ltd.
Polymerization Initiator, Ciba Specialty Chemicals, Inc. Irgacure 184
Fluorine-containing resin particles, manufactured by Daikin Industries, Ltd. Lubron L-2

The obtained mixed solution was dispersed at 6000 rpm for 30 minutes with a stirring homogenizer (manufactured by AS ONE). Next, a dispersion treatment was carried out three times at a pressure of 70 MPa with a wet dispersion device Nanovader L-AS (manufactured by Yoshida Kikai Kogyo Co., Ltd.) to obtain a dispersion liquid.
This dispersion was immersed and coated on the charge transport layer within 1 hour after the completion of the dispersion treatment, and the obtained coating film was cured to form a protective layer having a film thickness of 5 μm. As the curing means, the means shown in Table 1 was used. Ultraviolet irradiation and electron beam irradiation were performed as follows.

-Ultraviolet irradiation The obtained coating film was dried at 50 ° C. for 6 minutes. Then, the support (irradiated body) was irradiated with ultraviolet rays for 60 seconds while rotating at 200 rpm. The ultraviolet irradiation conditions were set so that the integrated light intensity was 1000 mJ / cm ^{2 with a high-pressure mercury lamp.} Next, a protective layer having a film thickness of 5 μm was formed by heat treatment at 130 ° C. for 30 minutes.

-Electron beam irradiation The obtained coating film was dried at 50 ° C. for 6 minutes. Then, in nitrogen, the coating film was irradiated with an electron beam for 1.6 seconds while rotating the support (irradiated body) at 200 rpm. The electron beam irradiation conditions were set so that the absorbed dose was 8000 Gy at an acceleration voltage of 70 kV. Subsequently, the temperature was raised in nitrogen from 25 ° C. to 120 ° C. over 30 seconds to heat the coating film. The oxygen concentration in the atmosphere during electron beam irradiation and subsequent heating was 15 ppm. Next, a protective layer having a film thickness of 5 μm was formed by heat-treating in the air at 100 ° C. for 30 minutes.
As described above, electrophotographic photosensitive members of Examples 1 to 19 and Comparative Examples 1 to 4 were obtained.

<Evaluation of electrophotographic photosensitive member>
-Observation of matrix-domain structure The presence or absence of the matrix-domain structure of the protective layer was confirmed in the obtained electrophotographic photosensitive member. The photosensitive layer was cut and its cross section was observed with a scanning electron microscope. The results are shown in Table 2.

-Evaluation of adhesion between the surface layer and its lower layer The adhesion between the protective layer and the charge transport layer of the obtained electrophotographic photosensitive member was evaluated using the cross-cut method. Six notches reaching the substrate were made with a utility knife at a pitch of 1 mm. Six cuts intersecting this at 90 ° were also made in the same manner, and a grid of 25 squares was made. Cellotape (registered trademark) was strongly crimped to the grid portion, the edges of the tape were peeled off at a stretch at an angle of 45 °, and the adhesion was evaluated by the number of squares peeled off. The evaluation criteria are as follows, and the results are shown in Table 2.
A; 0 squares B; 1-5 squares C; 5 squares or more

-Evaluation of electrical characteristics The residual potential was measured by image output using an electrophotographic apparatus. When the charge transport is poor, the residual potential causes negative ghosting in electrophotographic processes with preexposure. This is because the static elimination is not completed before the second rotation process is started after the pre-exposure irradiation is performed in the first rotation process (the potential of the photoconductor at this time is called the residual potential). This is a phenomenon in which the history of the image pattern of the first rotation appears in the process.
The obtained electrophotographic photosensitive member was attached to a black station of iR-ADV C5255 manufactured by Canon Inc. The charging potential was set to -700V and the exposure potential was set to -300V, and the ghost chart was output. The ghost chart is an image in which a 1 cm square black solid is arranged on the image tip side of the entire halftone image. The density difference of the negative ghost was measured with an X-rite518JP / LP aperture 3.4 mm spectrodensometer manufactured by SDG Co., Ltd. The evaluation criteria are as follows, and the results are shown in Table 2.
A; No ghost occurrence B; Ghost occurrence, concentration step is less than Δ0.02 C; Ghost occurrence, concentration step is Δ0.02 or more

-Maintenance of low frictional force and evaluation of wear resistance The obtained electrophotographic photosensitive member was mounted on a black station of iR-ADV C5255 manufactured by Canon Inc. and subjected to a durability test. The charging potential was set to -700V and the exposure potential was -300V, and 100,000 charts were output with A4 size and a printing ratio of 5%.
Regarding the maintenance of low frictional force, the sound generated by the frictional force between the cleaning blade and the photoconductor, so-called blade squeal, was evaluated. After the durability test, the squeal when the photoconductor was stopped and the low-speed squeal that occurred when the drive speed was slow were evaluated. The evaluation criteria are as follows.
A: No squeal at stop and no squeal at low speed B; No squeal at stop and no squeal at low speed C; No squeal at stop and low speed squeal

Regarding the wear resistance, the film thickness before and after the durability test was measured with an eddy current type film thickness meter (Fisherscope, manufactured by Fisher Instruments), and the amount of scraping was calculated. Further, in order to evaluate the scratches on the surface layer, a halftone output was performed after the durability test, and the scratched image was evaluated as to whether or not a density step due to the scratches appeared in the image.
A; No scratch image generated B; Scratched image generated but difficult to see C; Scratched image generated The results of blade squeal, scratch image, and scraping amount are shown in Table 2.

In Comparative Example 1, since the charge transporting compound and the oil having a fluoropolyether structure were not added to the protective layer, both the electrical characteristics and the low frictional force were insufficient.
In Comparative Example 2, fluororesin particles were used to reduce the frictional force, but they could not be maintained after durability.
In Comparative Example 3, low frictional force could be maintained by using an oil having a fluoropolyether structure, but the electrical characteristics were insufficient because no charge transporting compound was added.
In Comparative Example 4, since a compound having no polymerizable functional group was used as the charge transporting compound, the adhesion was insufficient.

In the electrophotographic photosensitive member of the example, the matrix-domain structure was confirmed by observation, and the adhesion and the electrical characteristics were improved. In addition, both wear resistance and low frictional force have been maintained.

101 Support 102 Charge generation layer 103 Charge transport layer 104 Protective layer 201 Surface layer 202 Matrix 203 Domain 1 Electrophotographic photosensitive member 2 axes 3 Charging means 4 Exposure light 5 Developing means 6 Transfer means 7 Transfer material 8 Fixing means 9 Cleaning means 10 Pre-exposure light 11 Process cartridge 12 Guidance means

Claims (7)

An electrophotographic photosensitive member having a photosensitive layer and a surface layer.
The surface layer has a matrix-domain structure in its thickness direction.
The domain comprises an oil having a fluoropolyether structure.
The matrix is a cured product of the lower SL (A) or (B),
An electrophotographic photosensitive member characterized by this.
(A) A cured product of at least a charge-transporting compound having one polymerizable functional group, a compound having two or more polymerizable functional groups, and a compound represented by the following formula (1).
(B) A cured product of at least a charge-transporting compound having two polymerizable functional groups and a compound represented by the following formula (1).

(R ¹ is a hydrogen atom or a methyl group. ^{R 2} is a linear or branched alkyl group having 8 to 20 carbon atoms.) The charge-transporting compound is a compound represented by a compound or formula represented by the following formula (2) (3) The electrophotographic photosensitive member according to claim 1.

(In the formula ^(2), Ar 1 to Ar ³ has at least one polymerizable functional group of ^.Ar 1 to Ar ³ which represents an aryl group which may have a ^substituent, the Ar 1 to Ar ³ At least one of them has a substituent represented by the formula (4) or a substituent represented by the formula (5). However, the aryl group having the polymerizable functional group as the substituent is represented by the formula (4) and the formula (4). It does not have the substituent indicated by 5).)

(In formula (3), Ar ^{4 to} Ar ⁷ indicate an aryl group which may have a substituent, and Ar ^{8 and Ar 9} indicate an arylene group which may have a substituent. ^{Ar 4 to} Ar. ^At least one of 9 has a polymerizable functional group, and ^{at least one of Ar 4 to} Ar ⁹ has a substituent represented by the formula (4) or a substituent represented by the formula (5), provided that the substituent is substituted. The aryl group having the polymerizable functional group as a group and the arylene group do not have the substituents represented by the formulas (4) and (5).

(P represents 0 or 1. q represents an integer of 0 to 2. R ¹ and R ² represent hydrogen atoms or methyl groups, respectively, and R ³ represents a perfluoroalkyl group having 7 or less carbon atoms. )

(In formula (5), Ar ¹⁰ represents a group obtained by removing u hydrogen atoms from an aryl group which may have a substituent. S represents 0 or 1. t represents an integer of 0 to 2. .U represents an integer of 1 or more. S + t ≧ 1, R ⁴ and R ⁵ each represent a hydrogen atom or a methyl group, and R ⁶ represents a perfluoroalkyl group having 7 or less carbon atoms.)) Said surface layer, as a dispersing agent for dispersing the oil having a fluoropolyether structure in the matrix,
A block copolymer obtained by copolymerizing a vinyl monomer having a fluoroalkyl group with acrylate or methacrylate, and
Comb-type graft copolymer obtained by copolymerizing fluoroalkyl acrylate or fluoroalkyl methacrylate with a methacrylate macromonomer having polymethyl methacrylate in the side chain.
Including at least one selected from the group consisting of
The electrophotographic photosensitive member according to claim 1 or 2. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to any one of claims 1 to 3 , as well as charging means, exposure means, developing means, and transfer means. The electrophotographic photosensitive member according to any one of claims 1 to 3 and at least one means selected from charging means, developing means and cleaning means are integrally supported, and can be attached to and detached from the main body of the electrophotographic apparatus. A process cartridge characterized by being. A method for producing an electrophotographic photosensitive member according to any one of claims 1 to 3, wherein the electrophotographic photosensitive member is produced.
As the step of forming the surface layer,
Under Symbol (A) or the step of work made of mixed-solution (B),
A step of performing a dispersion treatment on the mixed liquid to obtain a dispersion liquid,
The step of applying the dispersion liquid to form a coating film, and
The step of forming the surface layer by curing the coating film,
A method for producing an electrophotographic photosensitive member having at least.
(A) the charge transporting compound polymerizable functional group having one, wherein the polymerizable functional group of the compound having two or more, an oil having a fluoropolyether structure, the compound represented by the formula (1) A mixed solution containing at least and.
(B) the polymerizable functional group charge transporting compound having two, wherein an oil having a fluoropolyether structure with a compound represented by the formula (1), a mixed solution containing at least. The method for producing an electrophotographic photosensitive member according to claim 6 , wherein the step of curing the coating film to form a surface layer is a step of irradiating the coating film with an electron beam to cure the coating film.

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