JP2015184342A - Electrophotographic device and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic device having an electrophotographic photoreceptor and charging means, and employing contact-charging system, configured to effectively prevent image deletion even when images are formed repeatedly for a long time.SOLUTION: In contact-charging system, charging means applies a voltage to a roller-shaped charging member in contact with an electrophotographic photoreceptor with a nip, to charge the electrophotographic photoreceptor. A surface layer of the electrophotographic photoreceptor contains a specific urea compound, or a polymer substance of a composition including a charge transport compound having a chain polymerizable functional group and the specific urea compound.

Description

  The present invention relates to an electrophotographic apparatus and a process cartridge.

  As an electrophotographic photosensitive member mounted on an electrophotographic apparatus, there is an electrophotographic photosensitive member containing an organic photoconductive substance (charge generating substance), and extensive studies have been made so far. In recent years, the mechanical durability (abrasion resistance) of an electrophotographic photosensitive member has been demanded for the purpose of extending the life, improving the image quality, and reducing the size of the electrophotographic apparatus.

  Patent Document 1 discloses a technique in which a surface layer contains a polymer obtained by polymerizing a charge transporting compound having two or more chain polymerizable functional groups. This technique is described to improve the mechanical durability and potential stability of the electrophotographic photosensitive member.

  On the other hand, in order to reduce the size of the electrophotographic apparatus, a contact-type charging unit in the form of a roller, a so-called contact charging method, is used as a charging unit for charging the electrophotographic photosensitive member.

  However, when the mechanical durability of the electrophotographic photosensitive member is improved and the contact charging method is used as the charging means, an image quality defect such as image flow tends to occur.

  The image flow is a phenomenon in which the output image becomes thin or the fine lines become blurred or disappear due to the electrostatic latent image blurring particularly under high temperature and high humidity. This is because, in the contact charging method, the surface of the electrophotographic photosensitive member may be altered due to stress due to a discharge phenomenon, or discharge products (ozone, nitrogen oxide) generated by the discharge may remain on the surface of the electrophotographic photosensitive member. It is thought to be the cause.

  When the mechanical durability of the electrophotographic photosensitive member is low, the surface of the altered electrophotographic photosensitive member may be worn by friction of the cleaning blade or the contact charging roller, and the image flow may be suppressed. However, the electrophotographic photosensitive member having improved mechanical durability as in Patent Document 1 has a high wear resistance, and thus the effect of suppressing the image flow is not sufficient.

  As a means for suppressing this image flow, there is a method in which an additive is contained in the surface layer of the electrophotographic photosensitive member. Patent Document 2 describes a method of suppressing image flow by containing a specific amine compound in the surface layer of an electrophotographic photosensitive member containing a curable resin. Patent Document 3 describes that the urea layer is contained in the photosensitive layer to suppress the deterioration of the electrophotographic photosensitive member due to the active gas.

JP 2000-066425 A JP 2007-279678 A JP 63-097959 A

  However, as a result of the study by the present inventors, the amine compound described in Patent Document 2 and the urea compound described in Patent Document 3 are liable to lower the potential stability of the electrophotographic photosensitive member and have a low effect of suppressing image blur. I understood it.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic apparatus having an electrophotographic photosensitive member and a charging means, and having a high effect of suppressing image flow even when an image is repeatedly formed for a long period of time in an electrophotographic apparatus using a contact charging method. It is in. Another object of the present invention is to provide a process cartridge that has an electrophotographic photosensitive member and a charging unit, and that has a high effect of suppressing image flow even when an image is repeatedly formed over a long period of time using a contact charging method. It is in.

  The above object is achieved by the present invention described below.

The present invention is an electrophotographic photosensitive member and an electrophotographic apparatus having a charging means,
The charging means is a contact charging method in which a voltage is applied to a roller-shaped charging member brought into contact with the electrophotographic photosensitive member with a nip to charge the electrophotographic photosensitive member,
The electrophotographic photoreceptor has a surface layer containing a polymer of a charge transporting compound having a chain polymerizable functional group, and a urea compound,
The urea compound is at least one selected from the group consisting of a compound represented by the following formula (1), a compound represented by the following formula (2), and a compound represented by the following formula (3). The present invention relates to an electrophotographic apparatus.

(In the formula ^{(1) ~ (3),} R 1 ~R 4, R 11 ~R 16, R 21 ~R 28 are each ^{independently, .Ar} 2, Ar ¹² ~Ar 13 represents an alkyl group, ^{Ar 22} To Ar ²⁴ each independently represents a substituted or unsubstituted arylene group, Ar ¹ , Ar ³ , Ar ¹¹ , Ar ¹⁴ , Ar ²¹ , Ar ²⁵ each independently represents a substituted or unsubstituted aryl group; The substituent of the substituted arylene group is an alkyl group, an alkoxy-substituted alkyl group, a halogen-substituted alkyl group, an alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, or a halogen atom. Examples of the substituent include a cyano group, a dialkylamino group, a hydroxyl group, an alkyl group, an alkoxy-substituted alkyl group, and a halogen-substituted alkyl group. , An alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, a nitro group, or a halogen atom.)

The present invention also provides an electrophotographic photosensitive member and an electrophotographic apparatus having a charging means,
The charging means is a contact charging method in which a voltage is applied to a roller-shaped charging member brought into contact with the electrophotographic photosensitive member with a nip to charge the electrophotographic photosensitive member,
The electrophotographic photoreceptor has a surface layer containing a polymer of a composition containing a charge transporting compound having a chain polymerizable functional group and a urea compound having an acryloyloxy group or a methacryloyloxy group,
The present invention relates to an electrophotographic apparatus, wherein the urea compound is at least one selected from the group consisting of a compound represented by the following formula (4) and a compound represented by the following formula (5).

(In formulas (4) to (5), R ³¹ to ³² and R ^{41 to} R ⁴⁴ each independently represent an alkylene group. Ar ⁴² represents a substituted or unsubstituted arylene group. Ar 31, Ar 32, Ar 41 , Ar ⁴³ each independently represents a substituted or unsubstituted aryl group, and P ^{1 to} P ² and P ^{11 to} P ¹⁴ each independently represent a hydrogen atom, an acryloyloxy group, or a methacryloyloxy group. At least one of P ^{1 to} P ² is an acryloyloxy group or a methacryloyloxy group, and at least one of P ^{1 to} P ² and P ^{11 to} P ¹⁴ is an acryloyloxy group or a methacryloyloxy group. Examples of the substituent of the substituted arylene group include an alkyl group, an alkoxy-substituted alkyl group, a halogen-substituted alkyl group, A alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, or a halogen atom, which may be a cyano group, a dialkylamino group, a hydroxyl group, an alkyl group, an alkoxy-substituted alkyl group, or a halogen-substituted alkyl. Group, alkoxy group, alkoxy-substituted alkoxy group, halogen-substituted alkoxy group, acryloyloxy-substituted alkylene group, methacryloyloxy-substituted alkylene group, nitro group, or halogen atom.)

  A second invention according to the present application is an electrophotographic apparatus having an electrophotographic photosensitive member and using a contact charging method, wherein the electrophotographic photosensitive member has a charge transporting compound having a chain polymerizable functional group, and chain polymerization. A surface layer containing a polymer obtained by polymerizing a urea compound having a functional functional group, the urea compound having at least one urea moiety having a carbonyl group and two nitrogen atoms, The present invention relates to an electrophotographic apparatus having an electrophotographic photosensitive member, wherein each of the two nitrogen atoms is a nitrogen atom bonded to an alkylene group and a substituted or unsubstituted aryl or arylene group.

The present invention also provides a process cartridge that integrally supports the electrophotographic photosensitive member and the charging unit and is detachable from the electrophotographic apparatus main body.
The charging means is a contact charging method in which a voltage is applied to a roller-shaped charging member brought into contact with the electrophotographic photosensitive member with a nip to charge the electrophotographic photosensitive member,
The electrophotographic photoreceptor has a surface layer containing a polymer of a charge transporting compound having a chain polymerizable functional group, and a urea compound,
The urea compound is at least one selected from the group consisting of a compound represented by the above formula (1), a compound represented by the above formula (2), and a compound represented by the above formula (3). The present invention relates to a process cartridge.

The present invention also provides a process cartridge that integrally supports the electrophotographic photosensitive member and the charging unit and is detachable from the electrophotographic apparatus main body.
The charging means is a contact charging method in which a voltage is applied to a roller-shaped charging member brought into contact with the electrophotographic photosensitive member with a nip to charge the electrophotographic photosensitive member,
The electrophotographic photoreceptor has a surface layer containing a polymer of a composition containing a charge transporting compound having a chain polymerizable functional group and a urea compound having an acryloyloxy group or a methacryloyloxy group,
The process cartridge is characterized in that the urea compound is at least one selected from the group consisting of a compound represented by the above formula (4) and a compound represented by the above formula (5).

  According to the present invention, there is provided an electrophotographic apparatus having an electrophotographic photosensitive member and a charging unit and having a high effect of suppressing image flow even when an image is repeatedly formed for a long period of time in an electrophotographic apparatus using a contact charging method. Can do. In addition, according to the present invention, a process cartridge having an electrophotographic photosensitive member and a charging unit and using a contact charging method can provide a process cartridge having a high effect of suppressing image flow even when an image is repeatedly formed over a long period of time. Can do.

It is a figure which shows an example of the layer structure of an electrophotographic photoreceptor. 1 is a diagram illustrating an example of a schematic configuration of an electrophotographic apparatus having an electrophotographic photosensitive member.

  The present invention relates to an electrophotographic photosensitive member and an electrophotographic apparatus having a charging unit, or a process cartridge that integrally supports the electrophotographic photosensitive member and the charging unit and is detachable from the main body of the electrophotographic apparatus. The charging means is a contact charging method in which a voltage is applied to a roller-shaped charging member brought into contact with the electrophotographic photosensitive member with a nip to charge the electrophotographic photosensitive member.

  The electrophotographic photoreceptor has a surface layer containing a polymer of a charge transporting compound having a chain polymerizable functional group and a urea compound. The urea compound is at least one selected from the group consisting of a compound represented by the following formula (1), a compound represented by the following formula (2), and a compound represented by the following formula (3). And Alternatively, the electrophotographic photoreceptor has a surface layer containing a polymer of a composition containing a charge transporting compound having a chain polymerizable functional group and a urea compound having an acryloyloxy group or a methacryloyloxy group. The urea compound is at least one selected from the group consisting of a compound represented by the following formula (4) and a compound represented by the following formula (5).

In formulas (1) to (3), R ^{1 to} R ⁴ , R ^{11 to} R ¹⁶ , and R ^{21 to} R ²⁸ each independently represent an alkyl group. Ar ² , Ar ^{12 to} Ar ¹³ , and Ar ^{22 to} Ar ²⁴ each independently represent a substituted or unsubstituted arylene group. Ar ¹ , Ar ³ , Ar ¹¹ , Ar ¹⁴ , Ar ²¹ , Ar ²⁵ each independently represents a substituted or unsubstituted aryl group. The substituent of the substituted arylene group is an alkyl group, an alkoxy-substituted alkyl group, a halogen-substituted alkyl group, an alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, or a halogen atom. Examples of the substituent for the substituted aryl group include cyano group, dialkylamino group, hydroxyl group, alkyl group, alkoxy-substituted alkyl group, halogen-substituted alkyl group, alkoxy group, alkoxy-substituted alkoxy group, halogen-substituted alkoxy group, nitro group, and halogen Is an atom.

In formulas (4) to (5), R ³¹ to ³² and R ^{41 to} R ⁴⁴ each independently represent an alkylene group. Ar ⁴² represents a substituted or unsubstituted arylene group. Ar31, Ar32, Ar41, ^{Ar 43} each independently represent a substituted or unsubstituted aryl group. P ^{1 to} P ² and P ^{11 to} P ¹⁴ each independently represent a hydrogen atom, an acryloyloxy group, or a methacryloyloxy group. At least one of P ^{1 and} P ² is an acryloyloxy group or a methacryloyloxy group. At least one of P ^{1 to} P ² and P ^{11 to} P ¹⁴ is an acryloyloxy group or a methacryloyloxy group. The substituent of the substituted arylene group is an alkyl group, an alkoxy-substituted alkyl group, a halogen-substituted alkyl group, an alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, or a halogen atom. Examples of the substituent of the substituted aryl group include a cyano group, a dialkylamino group, a hydroxyl group, an alkyl group, an alkoxy substituted alkyl group, a halogen substituted alkyl group, an alkoxy group, an alkoxy substituted alkoxy group, a halogen substituted alkoxy group, and an acryloyloxy substituted alkylene group. , A methacryloyloxy-substituted alkylene group, a nitro group, or a halogen atom.

  The inventors presume the reason why the electrophotographic apparatus or the process cartridge of the present invention has a high effect of suppressing the image flow even when the image is repeatedly formed for a long period of time.

  As described above, the image flow is considered to be caused by the fact that the discharge product generated by the discharge remains on the surface of the electrophotographic photosensitive member. It has been pointed out in the technical literature that the discharge product remaining on the surface of the electrophotographic photosensitive member reacts with moisture in a humid environment to become nitric acid, causing an image flow (Sharp Technical Report No. 101, 2010). August “Establishment of quantitative evaluation method for image defects in copiers”). When nitric acid adheres to the surface layer of the electrophotographic photosensitive member, it acts on the charge transport material contained in the electrophotographic photosensitive member to generate ion pairs having a relatively long lifetime on the surface of the photosensitive member. The surface resistance will change. As a result, the potential difference between the image portion and the non-image portion is reduced particularly when printing fine lines and small characters, the electrostatic latent image is not retained, and the image density of the image forming portion is reduced (the image is blurred, It is thought that the image flow of “disappearing” has occurred.

  In the urea compound of the present invention, the aryl or arylene group, alkylene group, or alkyl group that the nitrogen atom has is preferentially compared with the nitric acid derived from the discharge product, compared to the aryl group that the charge transport material has. It is easy to form a short-lived ion pair. Therefore, it is assumed that the change in the surface resistance of the surface layer is suppressed, and as a result, the image flow is suppressed.

In the formula ^{(1) ~ (3),} R 1 ~R 4, R 11 ~R 16, R 21 ~R 28 each independently represent an alkyl group. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, and n-decyl group. Etc. Among these, a methyl group, an ethyl group, and an n-propyl group are preferable in that the sustainability of the sufficient effect of the present invention can be obtained.

In the formulas (1) to (3), Ar ² , Ar ^{12 to} Ar ¹³ , and Ar ^{22 to} Ar ²⁴ each independently represent a substituted or unsubstituted arylene group. Examples of the arylene group include a phenylene group, a biphenylene group, a fluorenylene group, and a naphthylene group. The substituent of the substituted arylene group is an alkyl group, an alkoxy-substituted alkyl group, a halogen-substituted alkyl group, an alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, or a halogen atom.

Examples of the alkyl group include a methyl group, an ethyl group, and an n-propyl group. Examples of the alkoxy-substituted alkyl group include a methoxymethyl group and an ethoxymethyl group. Examples of the halogen-substituted alkyl group include a trifluoromethyl group and a trichloromethyl group. Examples of the alkoxy group include a methoxy group and an ethoxy group. Examples of the alkoxy-substituted alkoxy group include a methoxymethoxy group and an ethoxymethoxy group. Examples of the halogen-substituted alkoxy group include a trifluoromethoxy group and a trichloromethoxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom. Ar ² , Ar ^{12 to} Ar ¹³ , and Ar ^{22 to} Ar ²⁴ are phenylene groups from the viewpoint of maintaining potential stability and obtaining an excellent image flow suppression effect by the urea compound and nitric acid generating more ion pairs. It is preferable that More preferably, it is an m-phenylene group.

In said formula (1)-(3), Ar < ¹ >, Ar < ³ >, Ar < ¹¹ >, Ar < ¹⁴ >, Ar < ²¹ >, Ar < ²⁵ > shows a substituted or unsubstituted aryl group each independently. Examples of the aryl group include a phenyl group, a biphenylyl group, a fluorenyl group, and a naphthylene group. Examples of the substituent for the substituted aryl group include cyano group, dialkylamino group, hydroxyl group, alkyl group, alkoxy-substituted alkyl group, halogen-substituted alkyl group, alkoxy group, alkoxy-substituted alkoxy group, halogen-substituted alkoxy group, nitro group, and halogen Is an atom.

  Examples of the dialkylamino group include a dimethylamino group and a diethylamino group. Examples of the alkyl group include a methyl group, an ethyl group, and an n-propyl group. Examples of the alkoxy-substituted alkyl group include a methoxymethyl group and an ethoxymethyl group. Examples of the halogen-substituted alkyl group include a trifluoromethyl group and a trichloromethyl group. Examples of the alkoxy group include a methoxy group and an ethoxy group. Examples of the alkoxy-substituted alkoxy group include a methoxymethoxy group and an ethoxymethoxy group. Examples of the halogen-substituted alkoxy group include a trifluoromethoxy group and a trichloromethoxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

Ar ¹ , Ar ³ , Ar ¹¹ , Ar ¹⁴ , Ar ²¹ , Ar ²⁵ are each independently an aryl group, methyl group, ethyl group, n-propyl group, trifluoromethyl group, methoxy group, dimethylamino group or fluorine. An aryl group substituted with an atom is preferable. With these groups, it is possible to maintain the potential stability, and the urea compound and nitric acid can generate more ion pairs and obtain an excellent image flow suppression effect.

More preferably, Ar ¹ , Ar ³ , Ar ¹¹ , Ar ¹⁴ , Ar ²¹ , Ar ²⁵ is preferably a phenyl group.

  The urea compound of the present invention is preferably contained in an amount of 0.1% by mass to 50% by mass with respect to the total mass of the surface layer of the electrophotographic photosensitive member. When the content is 0.1% by mass or more and 50% by mass or less, the potential stability is excellent, the image flow is further suppressed, and the film physical properties are also excellent.

  The urea compound of the present invention may contain only one type or two or more types in the surface layer of the electrophotographic photosensitive member.

  Specific examples of the compounds represented by the above formulas (1) to (3) are shown below, but the present invention is not limited thereto.

  More preferably, it is a compound shown by following formula (1-2).

  The surface layer of the electrophotographic photoreceptor contains a polymer of a composition containing a charge transporting compound having a chain polymerizable functional group and a urea compound having an acryloyloxy group or a methacryloyloxy group. The urea compound is at least one of a compound represented by the above formula (4) and a compound represented by the above formula (5).

  The polymer is obtained by polymerizing the chain polymerizable functional group of the charge transporting compound and the chain polymerizable functional group (acryloyloxy group, methacryloyloxy group) of the urea compound.

R ³¹ to ³² and R ^{41 to} R ⁴⁴ each independently represent an alkylene group. Examples of the alkylene group include a methylene group, an ethylene group, a propylene group, and a butylene group. An unsubstituted alkyl group such as a methyl group, an ethyl group, a propyl group, or a butyl group, an alkoxy-substituted alkyl group such as a methoxymethyl group or an ethoxymethyl group, or a halogen-substituted alkyl group such as a trifluoromethyl group or a trichloromethyl group may be used. . Ar ⁴² represents a substituted or unsubstituted arylene group. Ar ³¹ , Ar ³² , Ar ⁴¹ , Ar ⁴³ each independently represents a substituted or unsubstituted aryl group. P ^{1 to} P ² and P ^{11 to} P ¹⁴ each independently represent a hydrogen atom, an acryloyloxy group, or a methacryloyloxy group. At least one of P ^{1 to} P ² and P ^{11 to} P ¹⁴ is an acryloyloxy group or a methacryloyloxy group.

  Examples of the substituent of the substituted arylene group include an alkyl group, an alkoxy-substituted alkyl group, a halogen-substituted alkyl group, an alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, and a halogen atom.

  Examples of the substituent of the substituted aryl group include a cyano group, a dialkylamino group, a hydroxyl group, an alkyl group, an alkoxy substituted alkyl group, a halogen substituted alkyl group, an alkoxy group, an alkoxy substituted alkoxy group, a halogen substituted alkoxy group, and an acryloyloxy substituted alkylene group. , A methacryloyloxy-substituted alkylene group, a nitro group, or a halogen atom.

In the formula (4) and the formula (5), at least one of Ar ³¹ to ³² and at least one of Ar ⁴¹ to ⁴³ are preferably an ethylene-substituted aryl group or an n-propylene-substituted aryl group. . Alternatively, at least one of R ³¹ to ³² and at least one of R ⁴¹ to ⁴⁴ are preferably an ethylene group or an n-propylene group. When these substituents are used, the polymerization reaction is easily performed.

  Specific examples of the compounds represented by the above formulas (4) and (5) are given below, but the present invention is not limited thereto.

The urea compound of the present invention can be synthesized, for example, using a synthesis method described in the following literature.
-Photochem. Photobiol. Sci. , 2002, 1, P30-37
・ Transactions of the Faraday Society, 34,
1938, P783-786
・ Tetrahedron Letters 39 (1998) P6267-6270
・ Bulletin of the chemical society of Japan
an, vol. 47 (4), 1974, P935-937.

  The electrophotographic photosensitive member of the present invention has a support and a photosensitive layer formed on the support (FIGS. 1A and 1B). In the present invention, the photosensitive layer is separated into a single-layer type photosensitive layer containing a charge generation material and a charge transport material in the same layer, a charge generation layer containing a charge generation material, and a charge transport layer containing a charge transport material. And a laminated (functional separation type) photosensitive layer. In the electrophotographic photosensitive member of the present invention, a laminated photosensitive layer is preferable. In addition, the charge transport layer itself can have a laminated structure. A protective layer may be formed on the charge transport layer.

  In FIG. 1, 101 is a support, 102 is a charge generation layer, 103 is a charge transport layer, 104 is a protective layer, and 105 is a photosensitive layer. An intermediate layer may be provided between 101 and 102 as necessary.

  The surface layer of the electrophotographic photosensitive member of the present invention means a layer located on the outermost surface. For example, in the case of the electrophotographic photosensitive member having the layer structure shown in FIG. 1A, the surface layer of the electrophotographic photosensitive member is the charge transport layer 103. In the case of the electrophotographic photosensitive member having the layer structure shown in FIG. 1B, the surface layer of the electrophotographic photosensitive member is the protective layer 104.

  In the electrophotographic photosensitive member of the present invention, the surface layer is coated with the surface layer coating solution obtained by dissolving the urea compound of the present invention, the binder resin, and, if necessary, the charge transport material in a solvent. And this coating film can be dried. Alternatively, the surface layer is formed by applying a surface layer coating solution obtained by dissolving the urea compound of the present invention and a charge transporting compound having a chain polymerization functional group in a solvent to form a coating film, and polymerizing this. It can also be formed.

  The charge transporting compound is preferably a compound having two or more chain polymerizable functional groups in the same molecule. In addition, in the case where mechanical strength can be improved by using a polyfunctional monomer (a compound having two or more chain polymerizable functional groups in the same molecule and having no charge transporting ability), charge transport As the functional compound, a compound having only one chain polymerizable functional group can be used.

  The charge transporting compound is a compound having charge transporting ability. As the charge transporting compound (charge transporting substance), those having an aryl group or a heteroaryl group are generally used. For example, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, triarylamine derivatives, styrylanthracene, styrylpyra. Examples include zoline, phenylhydrazones, thiazole derivatives, triazole derivatives, benzofuran derivatives, benzimidazole derivatives, and N-phenylcarbazole derivatives.

  The charge transporting compound having a chain polymerizable functional group is preferably a compound disclosed in JP-A-2000-066425, JP-A-2000-206715, or JP-A-2000-206716. Furthermore, a compound represented by the following formula (6) is particularly preferable in terms of mechanical durability and potential stability.

In Formula 6, Ar ¹¹⁰ represents an aryl group which may have an alkyl group and / or an alkoxy group. R ¹⁰¹ and R ¹⁰² each independently represent a hydrogen atom or a methyl group. R ¹⁰³ and R ¹⁰⁴ each independently represents an alkylene group having 1 to 4 carbon atoms. Examples of the aryl group include a phenyl group, a biphenylyl group, and a fluorenyl group. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the alkoxy group include a methoxy group and an ethoxy group.

  As the binder resin used for the surface layer, polyvinyl butyral resin, polyarylate resin, polycarbonate resin, polyester resin, phenoxy resin, polyvinyl acetate resin, acrylic resin, polyacrylamide resin, polyamide resin, polyvinyl pyridine, cellulose resin, Examples include urethane resin, epoxy resin, agarose resin, casein, polyvinyl alcohol resin, and polyvinylpyrrolidone.

  Examples of the charge transport material used for the surface layer include triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, thiazole compounds, and triallylmethane compounds.

  Solvents used in the surface layer coating solution 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, tetrahydrofuran, dioxane and the like. Ether solvents, 1,1,2,2,3,3,4-heptafluorocyclopentane, halogen solvents such as dichloromethane, dichloroethane, chlorobenzene, aromatic solvents such as benzene, toluene, xylene, methyl cellosolve, ethyl Examples include cellosolve solvents such as cellosolve. These solvents may be used alone or in combination of two or more.

  Various additives can be added to the surface layer of the electrophotographic photoreceptor of the present invention. Additives include degradation inhibitors such as antioxidants and UV absorbers, lubricants such as polytetrafluoroethylene (PTFE) resin fine particles and fluorocarbons, and polymerization control agents such as polymerization reaction initiators and polymerization reaction terminators. Is mentioned.

  Next, the configuration of the electrophotographic photosensitive member used in the present invention will be described.

[Support]
Examples of the support (conductive support) of the electrophotographic photosensitive member of the present invention include metals or alloys such as aluminum, stainless steel, and nickel. In addition, a material in which a thin film of a metal such as aluminum or copper or a conductive material such as indium oxide or tin oxide is formed on an insulating support of a polyester resin or a polycarbonate resin. A resin impregnated with conductive particles such as carbon black, tin oxide particles and titanium oxide particles, or a plastic having a conductive binder resin can also be used. Examples of the shape of the support include a cylindrical shape and a sheet, but a cylindrical shape is preferable. In order to suppress interference fringes, it is preferable that the surface of the support is moderately roughened. Specifically, it is preferable to use a support that has been subjected to cutting treatment, roughening treatment, and alumite treatment.

  In the electrophotographic photoreceptor of the present invention, a conductive layer may be provided between the support and the photosensitive layer or intermediate layer. The conductive layer can be formed by applying a coating solution for conductive layer having conductive particles and resin on a support and drying the coating liquid. The conductive layer contains a powder containing conductive particles. Is done. Examples of the conductive particles include powders of metals and alloys such as carbon black, acetylene black, aluminum, zinc, copper, chromium, nickel and silver, and metal oxide powders such as tin oxide and ITO. Further, rough particles may be included to suppress interference fringes.

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

  Examples of the solvent used for the conductive layer coating solution include ether solvents, alcohol solvents, ketone solvents, and aromatic hydrocarbon solvents. The 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.

  In the electrophotographic photoreceptor of the present invention, an intermediate layer may be provided between the support or the conductive layer and the photosensitive layer. The intermediate layer can be formed by applying a coating liquid for intermediate layer containing a resin on a support or a conductive layer, and drying or curing it.

  As the resin used for the intermediate layer, polyvinyl alcohol resin, poly-N-vinylimidazole resin, polyethylene oxide resin, ethyl cellulose, ethylene-acrylic acid copolymer, casein, polyamide resin, N-methoxymethylated 6 nylon, copolymer Nylon etc. are mentioned. Moreover, the above-mentioned electroconductive particle can also be contained in an intermediate | middle layer.

Examples of the solvent for the intermediate layer coating solution include ether solvents, alcohol solvents, ketone solvents, and aromatic hydrocarbon solvents. The thickness of the intermediate layer is preferably 0.05 μm or more and 40 μm or less, and more preferably 0.4 to 20 μm.
Further, the intermediate layer may contain semiconductive particles, an electron transporting material, or an electron accepting material.

(Photosensitive layer)
In the electrophotographic photoreceptor of the present invention, a photosensitive layer (charge generation layer, charge transport layer) is formed on the support, the conductive layer, or the intermediate layer.

  Examples of charge generating materials used in the electrophotographic photoreceptor of the present invention include pyrylium, thiapyrylium dyes, phthalocyanine compounds, anthanthrone pigments, dibenzpyrenequinone pigments, pyranthrone pigments, azo pigments, indigo pigments, quinacridone pigments, quinocyanine pigments, and the like. Can be mentioned. Among these, gallium phthalocyanine is preferable.

  Furthermore, from the viewpoint of high sensitivity, hydroxygallium phthalocyanine crystals having peaks at 7.4 ° ± 0.3 ° and 28.2 ° ± 0.3 ° of the Bragg angle 2θ in CuKα characteristic X-ray diffraction are more preferable.

  In the laminated photosensitive layer, the binder resin used in the charge generation layer of the present invention includes polymers and copolymers of vinyl compounds such as styrene, vinyl acetate, and vinyl chloride, polyvinyl alcohol resins, polyvinyl acetal resins, and polyvinyl benzenes. Examples thereof include saar resin, polycarbonate resin, polyester resin, polysulfone resin, polyphenylene oxide, polyurethane resin, cellulose resin, phenol resin, melamine resin, silicon resin, and epoxy resin. These can be used singly or in combination of two or more as a mixture or copolymer.

  The charge generation layer can be formed by applying a charge generation layer coating solution obtained by dispersing a charge generation material together with a binder resin and a solvent and drying the coating solution. The charge generation layer may be a vapor generation film of a charge generation material.

  In the charge generation layer, the ratio of the charge generation material to the binder resin is preferably 0.3 parts by mass or more and 4 parts by mass or less for the binder resin with respect to 1 part by mass of the charge generation material. Examples of the dispersion method include a method using a homogenizer, an ultrasonic wave, a ball mill, a sand mill, an attritor, and a roll mill.

  Examples of the solvent used in the charge generation layer coating solution include alcohol solvents, sulfoxide solvents, ketone solvents, ether solvents, ester solvents, and aromatic hydrocarbon solvents. The thickness of the charge generation layer is preferably from 0.01 μm to 5 μm, and more preferably from 0.1 μm to 1 μm. Various sensitizers, antioxidants, ultraviolet absorbers, plasticizers and the like can be added as necessary.

  In the electrophotographic photoreceptor having a multilayer photosensitive layer, a charge transport layer is formed on the charge generation layer.

  When the charge transport layer is a surface layer as shown in FIG. 1A, the charge transport layer is formed as follows. That is, a coating film of a coating solution for a charge transport layer obtained by dissolving the urea compound, charge transport material, and binder resin of the present invention in a solvent is formed on the charge generation layer, and the coating film is dried. Can be formed.

  Alternatively, a coating film of a coating solution for a charge transport layer obtained by dissolving the urea compound of the present invention and a charge transport compound having a chain polymerizable functional group in a solvent is formed on the charge generation layer. It is obtained by polymerizing.

  When a protective layer is formed on the charge transport layer and the protective layer is a surface layer, the charge transport layer generates a charge coating film of the charge transport layer coating solution containing the charge transport material and the binder resin. It can form by forming on a layer and drying this coating film.

  Examples of the charge transporting compound having a chain polymerizable functional group used in the charge transporting layer include the same as the charge transporting compound having a chain polymerizable functional group used in the surface layer. The charge transporting compound having a chain polymerizable functional group is preferably 20% by mass or more and 99% by mass or less based on the total solid content of the charge transport layer coating solution.

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

  In the present invention, a protective layer may be provided on the charge transport layer. The protective layer is formed by forming a coating film of the coating liquid for the protective layer containing the binder resin and the urea compound of the present invention and, if necessary, the charge transport material on the charge transport layer, and drying the coating film. Can be formed. In addition, a coating film of a coating liquid for a protective layer containing a charge transporting compound having a chain polymerizable functional group and the urea compound of the present invention is formed on the charge transporting layer and polymerized. You can also.

  Examples of the charge transport material used in the protective layer include the same charge transport materials as those used in the surface layer. The ratio of the charge transport material is preferably 30% by mass to 70% by mass with respect to the total mass of the protective layer. Examples of the binder resin used in the protective layer include the same binder resins used in the surface layer described above.

  Examples of the charge transporting compound having a chain polymerizable functional group used in the protective layer may be the same as the charge transporting compound having a chain polymerizable functional group used in the surface layer. The charge transporting compound having a chain polymerizable functional group is preferably 20% by mass or more and 99% by mass or less with respect to the total solid content of the coating solution for the surface layer.

  The thickness of the protective layer is preferably 5 μm or more and 20 μm or less.

  When applying the coating liquid for each of the above layers, a coating method such as a dip 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.

  In the present invention, the means for carrying out the polymerization reaction when forming the surface layer is as follows. A surface layer is formed by forming a coating film using a coating solution for a surface layer containing a charge transporting compound having a chain polymerizable functional group and the urea compound of the present invention, and polymerizing the coating film.

  The polymerization reaction means for forming the surface layer can be performed using heat, light (such as ultraviolet rays), or radiation (such as electron beams). Among these, polymerization using radiation is preferable, and polymerization using an electron beam is more preferable.

  When polymerization is performed using an electron beam, a very high density three-dimensional network structure is obtained, and good potential stability is obtained. Further, the productivity is high because it is a short and efficient polymerization reaction. When irradiating with an electron beam, any of a scanning type, an electro curtain type, a broad beam type, a pulse type, and a laminar type can be used as an accelerator.

  When irradiating an electron beam, preferable irradiation conditions are as follows. In the present invention, the acceleration voltage is preferably 120 KV or less, more preferably 80 KV or less. The absorbed dose of the electron beam is preferably 1 × 10 3 to 1 × 10 5 Gy, and more preferably 5 × 10 3 to 5 × 10 4 Gy.

  In addition, when a charge transporting compound having a chain polymerizable functional group is polymerized using an electron beam, after irradiating the electron beam in an inert gas atmosphere for the purpose of removing the polymerization inhibiting action due to oxygen, It is preferable to heat. Examples of the inert gas include nitrogen, argon, helium and the like.

  In the present invention, the surface layer of the electrophotographic photosensitive member may be roughened for the purpose of improving cleaning properties. Examples of the roughening treatment include a method of rubbing a polishing sheet on the outermost surface layer, and a method of transferring the shape of a mold member having an uneven shape to form an uneven shape on the surface of the surface layer.

  In the present invention, the electrophotographic apparatus or the process cartridge includes a charging unit, and the charging unit applies a voltage to a roller-shaped charging member that is brought into contact with the electrophotographic photosensitive member with a nip, and thereby the electrophotographic photosensitive member. This is a contact charging method for charging. As the voltage to be applied, a DC power source or a DC voltage on which an AC voltage is superimposed is used.

  FIG. 2 shows an example of a schematic configuration of an electrophotographic apparatus provided with a process cartridge having the electrophotographic photosensitive member of the present invention.

  In FIG. 2, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is rotationally driven around a shaft 2 at a predetermined peripheral speed (process speed) in the direction of an arrow. In the rotation process, the electrophotographic photosensitive member 1 is uniformly charged with a predetermined positive or negative potential on its peripheral surface by a contact charging means (primary charging means) 3. The contact charging means 3 is a roller comprising an elastic layer made of conductive rubber or the like and a resistance layer for resistance adjustment on a cored bar.

  Next, the exposure light 4 intensity-modulated in response to a time-series electric digital image signal of target image information output from an exposure means (not shown) such as slit exposure or laser beam scanning exposure is received. In this way, electrostatic latent images corresponding to target image information are sequentially formed on the surface of the electrophotographic photosensitive member 1.

  The formed electrostatic latent image is then visualized as a toner image by the developing means 5 using a dry two-component developing system. The toner image formed and supported on the surface of the electrophotographic photosensitive member 1 is sequentially transferred to the belt-like primary transfer member 7 by the primary transfer means 6.

  In the case of a multicolor electrophotographic apparatus, toner images of other colors are transferred and superimposed on the primary transfer member 7 from a process cartridge (not shown) having the same configuration as the process cartridge 11.

  The primary transfer member 7 that has received the transfer of the toner image is separated from the surface of the electrophotographic photosensitive member and transferred to the secondary transfer member 13 by the secondary transfer means 14. Toner remaining on the primary transfer member 7 without being transferred is removed by a cleaning member (not shown).

  The secondary transfer member 13 is conveyed to the fixing unit 15 and is subjected to a toner image fixing process to be printed out as an image formed product (print, copy) outside the electrophotographic apparatus.

  On the surface of the electrophotographic photosensitive member 1 after the toner image is transferred, first, a discharge product generated by the charging unit is removed by a brush cleaner 8 made of a nylon brush, and deposits such as transfer residual toner are removed by the cleaning unit 9. After being removed, the surface is cleaned. The transfer residual toner can be collected by a developing device or the like. Further, if necessary, the charge is removed by pre-exposure light 10 from a pre-exposure means (not shown) and then repeatedly used for image formation. In the case of the contact charging method, pre-exposure is not always necessary.

  Hereinafter, the present invention will be described in more detail with reference to specific examples. In the examples, “part” means “part by mass”.

(Example of toner production)
<Manufacture of binder resin 1>
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane 74.5 parts (0.162 mol), terephthalic acid 24.3 parts (0.146 mol), and titanium tetrabutoxide 0 .5 parts were put into a glass 4-liter four-necked flask, and a thermometer, a stirring rod, a condenser and a nitrogen introducing tube were attached and placed in a mantle heater. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 3.5 hours while stirring at a temperature of 200 ° C. (First Reaction Step) Thereafter, 3.0 parts (0.015 mol) of trimellitic anhydride was added and reacted at 190 ° C. for 1 hour (second reaction step) to obtain a binder resin 1.

<Manufacture of binder resin 2>
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane 70.6 parts (0.153 mol), terephthalic acid 24.3 parts (0.146 mol), and titanium tetrabutoxide 0 .6 parts were put into a glass 4-liter four-necked flask, and a thermometer, a stirring rod, a condenser and a nitrogen introducing tube were attached and placed in a mantle heater. Next, after replacing the inside of the flask with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 1.5 hours while stirring at a temperature of 200 ° C. (First Reaction Step) Thereafter, 5.0 parts (0.026 mol%) of trimellitic anhydride was added and reacted at 180 ° C. for 8 hours (second reaction step) to obtain a binder resin 2.

<Production of polymer A>
-18 parts of low density polyethylene (Mw 1400, Mn 850, DSC has a maximum endothermic peak of 100 ° C), 66 parts of styrene, 13.5 parts of n-butyl acrylate, 2.5 parts of acrylonitrile are charged into an autoclave, and the system is substituted with N 2 The temperature was maintained at 180 ° C. while stirring.

  Into the system, 50 parts of a 2% by weight t-butyl hydroperoxide xylene solution was continuously dropped for 5 hours, and after cooling, the solvent was separated and removed, and the polymer A in which the vinyl resin component reacted with the low-density polyethylene. Got.

  When the molecular weight of the polymer A was measured, it was weight average molecular weight (Mw) 7100 and number average molecular weight (Mn) 3000. Furthermore, the transmittance at a wavelength of 600 nm measured at a temperature of 25 ° C. in a dispersion dispersed in a 45 volume% methanol aqueous solution was 69%.

<Manufacture of cyan toner>
Binder resin 1 (60 parts), binder resin 2 (40 parts), Fischer-Tropsch wax (peak temperature of maximum endothermic peak 90 ° C.) 6 parts, C.I. I. Pigment Blue 15: 3 (5 parts), 3,5-di-t-butylsalicylic acid aluminum compound (0.2 parts), and polymer A5 parts were replaced with a Henschel mixer (FM-75 type, manufactured by Mitsui Mining Co., Ltd.). And mixed at a rotation speed of 20 s-1 and a rotation time of 5 min. Then, it knead | mixed with the biaxial kneader (PCM-30 type | mold, Ikegai Co., Ltd. product) set to the temperature of 140 degreeC. The obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized material. The obtained coarsely crushed material was finely pulverized with a mechanical pulverizer (T-250, manufactured by Turbo Kogyo Co., Ltd.). To 100 parts of the finely pulverized product, 4.0 parts of hydrophobic silica fine particles having a BET specific surface area of 30 m ² / g surface-treated with 5% by mass of hexamethyldisilazane and BET surface-treated with 10% by mass of isobutyltrimethoxysilane. 0.5 parts of titanium oxide fine particles having a specific surface area of 180 m ² / g were added. This is mixed with a Henschel mixer (FM-10 type, manufactured by Nippon Coke Mining Co., Ltd.) at a rotation speed of 65 s-1 and a rotation time of 5 minutes, and heat treated by a thermal surface treatment apparatus to obtain a cyan toner used in this example. It was.

The cyan toner thus obtained had an average circularity of 0.968, a weight average particle diameter (D4) of 7.2 μm, and the proportion of inorganic fine particles fixed to the toner particle surface was 30%.

(Example of manufacturing magnetic carrier)
<Manufacture of magnetic core particles>
The ferrite raw material was weighed so as to be 60.2 parts Fe ₂ O ₃ , 33.9 parts MnCO ₃ , 4.8 parts Mg (OH) ₂ , and 1.1 parts SrCO ₃ . Thereafter, the mixture was pulverized and mixed for 2 hours in a dry ball mill using zirconia balls having a diameter of 10 mm.

  After pulverization and mixing, firing was performed in the atmosphere at a temperature of 950 ° C. for 2 hours using a burner-type firing furnace to prepare calcined ferrite. The composition of the ferrite was as follows.

(MnO) 0.387 (MgO) 0.108 (SrO) 0.010 (Fe2O3) 0.495
After crushing to about 0.5 mm with a crusher, 30 parts of water was added to 100 parts of calcined ferrite using a ball of stainless steel having a diameter of 10 mm, and pulverized for 6 hours with a wet ball mill.

  The slurry was pulverized for 3 hours by a wet bead mill using zirconia beads having a diameter of 1.0 mm to obtain a ferrite slurry.

  To the ferrite slurry, 2.0 parts of polyvinyl alcohol was added as a binder with respect to 100 parts of calcined ferrite, and granulated into spherical particles of about 36 μm with a spray dryer (manufacturer: Okawara Chemical).

  In order to control the firing atmosphere, firing was performed in an electric furnace in a nitrogen atmosphere (oxygen concentration of 0.01% by volume or less) at a temperature of 1300 ° C. for 4 hours.

  After the aggregated particles were crushed, coarse particles were removed by sieving with a sieve having an opening of 250 μm to obtain magnetic core particles 1.

<Manufacture of magnetic carrier>
Straight silicone resin (SR2411 Toray Dow Corning) 20.0 parts (kinematic viscosity in 20 parts toluene solution 1.1 × 10 −4 m 2 / sec)
γ-Aminopropyltriethoxysilane 0.5 part Toluene 79.0 parts The above materials were mixed so as to have the above composition ratio to obtain a resin liquid 1.

  Resin liquid 1 was charged into a Nauter mixer so as to be 1.0 part as a resin component. It heated at 70 degreeC under pressure reduction, mixed by 1.7S-1 (100 rpm), and solvent removal and application | coating operation were performed over 4 hours. Thereafter, the obtained sample was transferred to a Julia mixer, heat-treated for 2 hours at a temperature of 200 ° C. in a nitrogen atmosphere, and then classified with a sieve having an opening of 70 μm to obtain a magnetic carrier 1. The obtained magnetic carrier 1 had a volume distribution standard 50% particle size (D50) of 37.5 μm.

  The cyan toner obtained in the above process and the magnetic carrier were mixed so that the toner concentration would be 8% to obtain a two-component developer.

Example 1
<Manufacture of electrophotographic photoreceptor>
An aluminum cylinder having a diameter of 30 mm, a length of 357.5 mm, and a wall thickness of 1 mm was used as a support (conductive support).

Next, 100 parts of zinc oxide particles (specific surface area: 19 m ² / g, powder resistance: 4.7 × 10 ⁶ Ω · cm) are stirred and mixed with 500 parts of toluene, and 0.8 part of a silane coupling agent is added thereto. Was added and stirred for 6 hours. Thereafter, toluene was distilled off under reduced pressure, followed by heating and drying at 130 ° C. for 6 hours to obtain surface-treated zinc oxide particles. As the silane coupling agent, KBM602 (compound name: N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. was used.

  Next, as a polyol resin, 15 parts of polyvinyl butyral resin (weight average molecular weight: 40000, trade name: BM-1, manufactured by Sekisui Chemical Co., Ltd.) and blocked isocyanate (trade name: Sumidur 3175, Sumika Bayer Urethane ( 15 parts) was dissolved in a mixed solution of 73.5 parts of methyl ethyl ketone and 73.5 parts of 1-butanol.

  80.8 parts of surface-treated zinc oxide particles and 0.8 part of 2,3,4-trihydroxybenzophenone (manufactured by Tokyo Chemical Industry Co., Ltd.) were added to this solution, and this was added to glass beads having a diameter of 0.8 mm. Was dispersed 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 Co., Ltd.) was added. Furthermore, 5.6 parts of cross-linked polymethyl methacrylate (PMMA) particles (trade name: TECHPOLYMER SSX-102, manufactured by Sekisui Plastics Co., Ltd., average primary particle size 2.5 μm) were added and stirred, and the undercoat layer was added. A coating solution was prepared.

  This undercoat layer coating solution was dip-coated on the aluminum cylinder to form a coating film, and the resulting coating film was dried at 160 ° C. for 40 minutes to form an undercoat layer having a thickness of 18 μm.

Next, crystal form hydroxygallium phthalocyanine crystals having peaks at 7.4 ° and 28.2 ° of black angle 2θ ± 0.2 ° of CuKα characteristic X-ray diffraction were prepared. 20 parts of this hydroxygallium phthalocyanine crystal, 0.2 part of a compound represented by the following formula (6), 10 parts of polyvinyl butyral resin (trade name: ESREC BX-1, manufactured by Sekisui Chemical Co., Ltd.) and 600 parts of cyclohexanone, The dispersion was carried out for 4 hours by a sand mill using glass beads having a diameter of 1 mm.
Thereafter, 700 parts of ethyl acetate was added to prepare a coating solution for charge generation layer. This coating solution for charge generation layer is dip-coated on the undercoat layer to form a coating film, and the resulting coating film is heated and dried in an oven at a temperature of 80 ° C. for 15 minutes, whereby the film thickness is 0.17 μm. A charge generation layer was formed.

  Next, 30 parts of a compound represented by the following formula (7) (charge transporting substance), 60 parts of a compound represented by the following formula (8) (charge transporting substance), 10 parts of a compound represented by the following formula (9), polycarbonate 100 parts of resin (trade name: Iupilon Z400, manufactured by Mitsubishi Engineering Plastics Co., Ltd., bisphenol Z type), polycarbonate having a structural unit represented by the following formulas (10) and (11) (viscosity average molecular weight Mv: 20000) 0 A coating solution for a charge transport layer was prepared by dissolving 0.02 part in a solvent of 600 parts of mixed xylene and 200 parts of dimethoxymethane.

  The charge transport layer coating solution was dip coated on the charge generation layer to form a coating film, and the resulting coating film was dried at 100 ° C. for 30 minutes to form a charge transport layer having a thickness of 18 μm.

  Next, 98 parts of the compound represented by the following formula (12), 2 parts of the exemplified compound (1-2) and 300 parts of 1-propanol were mixed and stirred. Next, 30 parts of polytetrafluoroethylene resin fine powder (Lublon L-2, manufactured by Daikin Industries, Ltd.) and 1.5 parts of comb-type fluorine-based graft polymer (GF300, manufactured by Toagosei Co., Ltd.) are added to the above. In addition to the solution, the mixture was dispersed and mixed with an ultrahigh pressure disperser to prepare a coating solution for a protective layer.

  This coating solution for protective layer was dip coated on the charge transport layer to form a coating film, and the resulting coating film was dried at 50 ° C. for 10 minutes in the air. Thereafter, the coating film was irradiated with an electron beam for 1.6 seconds under a nitrogen atmosphere while rotating the support (object to be irradiated) at a speed of 200 rpm under the conditions of an acceleration voltage of 150 kV and a beam current of 3.0 mA. In addition, when the absorbed dose of the electron beam at this time was measured, it was 15 kGy. Thereafter, in a nitrogen atmosphere, the temperature of the coating film was increased over 30 seconds until the temperature of the coating film changed from 25 ° C. to 125 ° C., and the coating film was heated. The oxygen concentration from the electron beam irradiation to the subsequent heat treatment was 15 ppm or less. Next, the film is naturally cooled in the atmosphere until the temperature of the coating film reaches 25 ° C., and subjected to a heat treatment for 30 minutes under the condition that the temperature of the coating film reaches 100 ° C. in the atmosphere. Layer).

  Next, a mold member was installed in the pressure contact shape transfer processing apparatus, and surface processing was performed on the electrophotographic photosensitive member on which the protective layer (surface layer) was formed. The mold member is composed of an elastic layer (silicon rubber), a metal layer (stainless steel), and a transfer layer (nickel). The concavo-convex shape of the transfer layer was a random (by error diffusion method (Floyd & Steinberg method)) convex portion arranged on a plane. The convex portion had a dome shape with a diameter of 50 μm and a height of 2 μm, and the area occupied by the convex portion on the entire surface of the transfer layer was 10%.

  During the surface processing, the temperature of the electrophotographic photosensitive member and the mold is controlled so that the surface temperature of the electrophotographic photosensitive member becomes 110 ° C., and the electrophotographic photosensitive member is moved in the circumferential direction while pressing the electrophotographic photosensitive member and the pressure member. Rotated. In this way, a recess was formed on the entire surface (circumferential surface) of the electrophotographic photosensitive member. Thus, an electrophotographic photosensitive member was produced.

<Evaluation of electrophotographic photoreceptor>
The electrophotographic photosensitive member and the two-component developer were introduced into the electrophotographic apparatus shown in FIG. 2 to evaluate the electrophotographic photosensitive member. Only one process cartridge was used, and the setting was cyan monochromatic.

  The peripheral speed (process speed) of the electrophotographic photosensitive member 1 was set to 200 mm / s, and the exposure writing resolution was set to 600 dpi.

  The electrophotographic apparatus is placed in a high-temperature and high-humidity environment (temperature 30 ° C., humidity 80% RH), and the contact charger is set using a DC voltage of −650 V on which an alternating voltage of 2000 Hz 1500 Vpp is superimposed. It was made to be charged to -650V (dark part potential Vd). The amount of exposure light was set such that the initial bright portion potential Vl was −200V.

  After continuously feeding 10,000 sheets of images with an image ratio of 5% on A4 vertical size paper, the power supply to the electrophotographic apparatus was stopped and left for 72 hours. Immediately after the power supply was resumed, a character image (E character image) in which a grid image (3 lines 30 spaces) and an alphabet E character image (font type: Times, font size 6 points) were repeated was output to A4 vertical size paper. .

  Similarly, the evaluation after a total of 50,000 sheets and after a total of 100,000 sheets was performed.

  Even after passing 100,000 sheets, there was no defect in the lattice image and the E character image, and the effect on the image flow of the urea compound (1-2) added to the surface layer was demonstrated.

  The results of this example are also shown in Table 1.

(Example 2)
In the manufacturing process of the electrophotographic photosensitive member in Example 1, the electrophotographic photosensitive member is formed in the same manner as in Example 1, and the protective layer (surface layer) is changed as follows to change the protective layer (surface layer) as follows. A photoreceptor was manufactured.

  97 parts of the compound represented by the above formula (12), 3 parts of exemplary compound (2-8), 3.5 parts of siloxane-modified acrylic compound (BYK-3550, manufactured by BYK Japan Japan Co., Ltd.), 300 parts of 1-propanol Were mixed and stirred to prepare a coating solution for a protective layer.

  Next, a protective layer (surface layer) having a film thickness of 5 μm was formed in exactly the same manner as in Example 1, and an electrophotographic photoreceptor having recesses formed on the entire surface in the same manner as in Example 1 was produced.

  The obtained electrophotographic photoreceptor was evaluated in exactly the same manner as in Example 1. As a result, an excellent effect on image flow was confirmed as in Example 1.

(Example 3)
A protective layer (surface layer) was formed in exactly the same manner as in Example 1 except that the exemplified compound (1-2) in Example 1 was changed to the exemplified compound (3-2).

  Next, surface processing was performed on the electrophotographic photosensitive member having a protective layer (surface layer) formed thereon using a polishing apparatus. While rotating the electrophotographic photosensitive member, a polishing sheet (trade name: GC # 3000, base layer thickness: 75 μm) manufactured by Riken Corundum was rubbed to roughen the surface.

  The obtained electrophotographic photoreceptor was evaluated in the same manner as in Example 1.

Example 4
Except that Example Compound (1-2) in Example 1 was changed to Example Compound (4-1) and the mass ratio was changed to 80 parts for Compound (12) and 20 parts for Example Compound (4-1). An electrophotographic photosensitive member was produced in exactly the same manner as in Example 1. Evaluation was performed in the same manner as in Example 1.

(Example 5)
Except that Example Compound (3-2) in Example 3 was changed to Example Compound (5-1), and the mass ratio was changed to 80 parts for Compound (12) and 20 parts for Example Compound (5-1). An electrophotographic photosensitive member was produced in exactly the same manner as in Example 3.

(Example 6)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the compound represented by the above formula (12) in Example 2 was changed to the compound represented by the following formula (13). Evaluation was performed in the same manner as in Example 1.

(Example 7)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the compound represented by the above formula (12) in Example 2 was changed to the compound represented by the following formula (14). Evaluation was performed in the same manner as in Example 1.

(Example 8)
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the compound represented by the above formula (12) in Example 2 was changed to the compound represented by the following formula (15). Evaluation was performed in the same manner as in Example 1.

  Evaluation was performed by changing the charging method of Example 1 and the contact charger. The voltage applied to the contact charger was only a DC voltage, and the dark part potential (Vd) on the surface of the electrophotographic photosensitive member was set to −650V. The DC voltage applied to the contact charger at this time was -1200V. Evaluation was performed in the same manner as in Example 1 under these conditions.

  In this example, the variation of the bright part potential (Vl) was within 30 V in all cases.

The evaluation index is shown below.
◎: No image defect in both grid image and E character image ○: Part of the lattice image is hazy, but there is no image defect in E character image

DESCRIPTION OF SYMBOLS 101 Support body 102 Charge generation layer 103 Charge transport layer 104 Protective layer 105 Photosensitive layer 1 Electrophotographic photoreceptor 2 Axis 3 Contact charging means 4 Exposure light 5 Developing means 6 Primary transfer means 7 Primary transfer member 8 Brush cleaner 9 Cleaning means 10 Previous Exposure light 11 Process cartridge 12 Guide means 13 Secondary transfer member 14 Secondary transfer means 15 Fixing means

Claims (8)

An electrophotographic photosensitive member and an electrophotographic apparatus having a charging means,
The charging means is a contact charging method in which a voltage is applied to a roller-shaped charging member brought into contact with the electrophotographic photosensitive member with a nip to charge the electrophotographic photosensitive member,
The electrophotographic photoreceptor has a surface layer containing a polymer of a charge transporting compound having a chain polymerizable functional group, and a urea compound,
The urea compound is at least one selected from the group consisting of a compound represented by the following formula (1), a compound represented by the following formula (2), and a compound represented by the following formula (3). An electrophotographic device.



(In the formula ^{(1) ~ (3),} R 1 ~R 4, R 11 ~R 16, R 21 ~R 28 are each ^{independently, .Ar} 2, Ar ¹² ~Ar 13 represents an alkyl group, ^{Ar 22} To Ar ²⁴ each independently represents a substituted or unsubstituted arylene group, Ar ¹ , Ar ³ , Ar ¹¹ , Ar ¹⁴ , Ar ²¹ , Ar ²⁵ each independently represents a substituted or unsubstituted aryl group; The substituent of the substituted arylene group is an alkyl group, an alkoxy-substituted alkyl group, a halogen-substituted alkyl group, an alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, or a halogen atom. Examples of the substituent include a cyano group, a dialkylamino group, a hydroxyl group, an alkyl group, an alkoxy-substituted alkyl group, and a halogen-substituted alkyl group. , An alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, a nitro group, or a halogen atom.) An electrophotographic photosensitive member and an electrophotographic apparatus having a charging means,
The charging means is a contact charging method in which a voltage is applied to a roller-shaped charging member brought into contact with the electrophotographic photosensitive member with a nip to charge the electrophotographic photosensitive member,
The electrophotographic photoreceptor has a surface layer containing a polymer of a composition containing a charge transporting compound having a chain polymerizable functional group and a urea compound having an acryloyloxy group or a methacryloyloxy group,
An electrophotographic apparatus, wherein the urea compound is at least one selected from the group consisting of a compound represented by the following formula (4) and a compound represented by the following formula (5).


(In formulas (4) to (5), R ³¹ to ³² and R ^{41 to} R ⁴⁴ each independently represent an alkylene group. Ar ⁴² represents a substituted or unsubstituted arylene group. Ar 31, Ar 32, Ar 41 , Ar ⁴³ each independently represents a substituted or unsubstituted aryl group, and P ^{1 to} P ² and P ^{11 to} P ¹⁴ each independently represent a hydrogen atom, an acryloyloxy group, or a methacryloyloxy group. At least one of P ^{1 to} P ² is an acryloyloxy group or a methacryloyloxy group, and at least one of P ^{1 to} P ² and P ^{11 to} P ¹⁴ is an acryloyloxy group or a methacryloyloxy group. Examples of the substituent of the substituted arylene group include an alkyl group, an alkoxy-substituted alkyl group, a halogen-substituted alkyl group, A alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, or a halogen atom, which may be a cyano group, a dialkylamino group, a hydroxyl group, an alkyl group, an alkoxy-substituted alkyl group, or a halogen-substituted alkyl. Group, alkoxy group, alkoxy-substituted alkoxy group, halogen-substituted alkoxy group, acryloyloxy-substituted alkylene group, methacryloyloxy-substituted alkylene group, nitro group, or halogen atom.)   The electrophotographic apparatus according to claim 1, wherein the voltage is a DC voltage.   The electrophotographic apparatus according to claim 1, wherein the voltage is a DC voltage on which an AC voltage is superimposed. In the process cartridge that integrally supports the electrophotographic photosensitive member and the charging unit and is detachable from the main body of the electrophotographic apparatus,
The charging means is a contact charging method in which a voltage is applied to a roller-shaped charging member brought into contact with the electrophotographic photosensitive member with a nip to charge the electrophotographic photosensitive member,
The electrophotographic photoreceptor has a surface layer containing a polymer of a charge transporting compound having a chain polymerizable functional group, and a urea compound,
The urea compound is at least one selected from the group consisting of a compound represented by the following formula (1), a compound represented by the following formula (2), and a compound represented by the following formula (3). To process cartridge.



(In the formula ^{(1) ~ (3),} R 1 ~R 4, R 11 ~R 16, R 21 ~R 28 are each ^{independently, .Ar} 2, Ar ¹² ~Ar 13 represents an alkyl group, ^{Ar 22} To Ar ²⁴ each independently represents a substituted or unsubstituted arylene group, Ar ¹ , Ar ³ , Ar ¹¹ , Ar ¹⁴ , Ar ²¹ , Ar ²⁵ each independently represents a substituted or unsubstituted aryl group; The substituent of the substituted arylene group is an alkyl group, an alkoxy-substituted alkyl group, a halogen-substituted alkyl group, an alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, or a halogen atom. Examples of the substituent include a cyano group, a dialkylamino group, a hydroxyl group, an alkyl group, an alkoxy-substituted alkyl group, and a halogen-substituted alkyl group. , An alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, a nitro group, or a halogen atom.) In the process cartridge that integrally supports the electrophotographic photosensitive member and the charging unit and is detachable from the main body of the electrophotographic apparatus,
The charging means is a contact charging method in which a voltage is applied to a roller-shaped charging member brought into contact with the electrophotographic photosensitive member with a nip to charge the electrophotographic photosensitive member,
The electrophotographic photoreceptor has a surface layer containing a polymer of a composition containing a charge transporting compound having a chain polymerizable functional group and a urea compound having an acryloyloxy group or a methacryloyloxy group,
A process cartridge, wherein the urea compound is at least one selected from the group consisting of a compound represented by the following formula (4) and a compound represented by the following formula (5).


(In formulas (4) to (5), R ³¹ to ³² and R ^{41 to} R ⁴⁴ each independently represent an alkylene group. Ar ⁴² represents a substituted or unsubstituted arylene group. Ar 31, Ar 32, Ar 41 , Ar ⁴³ each independently represents a substituted or unsubstituted aryl group, and P ^{1 to} P ² and P ^{11 to} P ¹⁴ each independently represent a hydrogen atom, an acryloyloxy group, or a methacryloyloxy group. At least one of P ^{1 to} P ² is an acryloyloxy group or a methacryloyloxy group, and at least one of P ^{1 to} P ² and P ^{11 to} P ¹⁴ is an acryloyloxy group or a methacryloyloxy group. Examples of the substituent of the substituted arylene group include an alkyl group, an alkoxy-substituted alkyl group, a halogen-substituted alkyl group, A alkoxy group, an alkoxy-substituted alkoxy group, a halogen-substituted alkoxy group, or a halogen atom, which may be a cyano group, a dialkylamino group, a hydroxyl group, an alkyl group, an alkoxy-substituted alkyl group, or a halogen-substituted alkyl. Group, alkoxy group, alkoxy-substituted alkoxy group, halogen-substituted alkoxy group, acryloyloxy-substituted alkylene group, methacryloyloxy-substituted alkylene group, nitro group, or halogen atom.)   The electrophotographic photosensitive member according to claim 5, wherein the voltage is a DC voltage. The electrophotographic photosensitive member according to claim 5, wherein the voltage is a DC voltage on which an AC voltage is superimposed.