JP6019917B2 - Electrophotographic photosensitive member, process cartridge, and image forming apparatus - Google Patents

Description

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

An electrophotographic image forming apparatus generally has the following configuration and process.
That is, the surface of the electrophotographic photosensitive member is charged to a predetermined polarity and potential by a charging unit, and the surface of the electrophotographic photosensitive member after charging is selectively neutralized by image exposure to form an electrostatic latent image, The toner is attached to the electrostatic latent image by the developing means, whereby the latent image is developed as a toner image, and the toner image is transferred to a transfer medium by the transfer means, and discharged as an image formed product. .

The following materials have been proposed for the material system of the protective layer (outermost surface layer) of the electrophotographic photosensitive member.
Patent Document 1 proposes an organic-inorganic hybrid material.
Patent Document 2 proposes a chain polymerizable material.
Patent Document 3 proposes an acrylic material.
Patent Documents 4 and 5 propose a radiation cross-linked material composed of a radiation cross-linking agent and a charge transport material.

  As another aspect of the outermost surface layer of the electrophotographic photosensitive member, for example, Patent Document 6 proposes a conductive powder dispersed in a phenol resin.

JP 2000-019749 A JP 2005-234546 A JP 2000-66424 A Japanese Patent Laid-Open No. 2004-240079 JP 2007-156081 A Japanese Patent No. 3287678

  An object of the present invention is to provide an electrophotographic photosensitive member in which deterioration of electrical characteristics is suppressed even when used repeatedly over a long period of time.

The above problem is solved by the following means. That is,
The invention according to claim 1 is an electrophotographic photosensitive member provided with a charge transporting layer containing a polymer of a compound represented by the following general formula (I).

In the general formula (I), F represents a charge transporting subunit , and the following partial structure (A) in the compound represented by the general formula (I) is represented by the following general formula (IV-1). Group, group represented by the following general formula (IV-2), group represented by the following general formula (V-1), or group represented by the following general formula (V-2) . m represents an integer of 1 to 6.

In the general formulas (IV-1) and (IV-2), X represents a linking group, and p represents 0 or 1. In the partial structure (A), the wavy line indicates the binding site with the charge transporting subunit indicated by F.
In the general formulas (V-1) and (V-2), X ′ represents a linking group, and p ′ represents 0 or 1. In the partial structure (A), the wavy line indicates the binding site with the charge transporting subunit indicated by F.

  The invention according to claim 2 is the electrophotographic photoreceptor according to claim 1, wherein the compound represented by the general formula (I) is a compound represented by the following general formula (II).

In the general formula (II), Ar ^{1 to} Ar ⁴ each independently represents a substituted or unsubstituted aryl group, Ar ⁵ represents a substituted or unsubstituted aryl group, or a substituted or unsubstituted arylene group, and D Is a group represented by the general formula (IV-1), a group represented by the general formula (IV-2), a group represented by the general formula (V-1), or the general formula (V- The group represented by 2) is shown. k is 0 or 1, c1 to c5 represent an integer of 0 to 2, that all of c1 to c5 becomes 0 at the same time have greens.

The invention according to claim 3 is the electrophotographic photosensitive member according to claim 1 or 2 , wherein the charge transporting layer is provided as an outermost surface layer.

The invention according to claim 4 is the electrophotographic photosensitive member according to any one of claims 1 to 3 , wherein the charge transporting layer further contains a thermal radical generator or a derivative thereof.

A fifth aspect of the present invention is a process cartridge that includes the electrophotographic photosensitive member according to any one of the first to fourth aspects and is detachable from an image forming apparatus.

According to a sixth aspect of the present invention, there is provided an electrophotographic photosensitive member according to any one of the first to fourth aspects of the present invention, a charging unit for charging the electrophotographic photosensitive member, and the electrostatically charged electrophotographic photosensitive member. An electrostatic latent image forming means for forming an electrostatic latent image; a developing means for developing the electrostatic latent image formed on the electrophotographic photosensitive member with toner to form a toner image; and the toner image on a transfer target. And an image forming apparatus including a transfer unit that transfers the image.

According to the first aspect of the present invention, even when the charge transporting layer containing the polymer of the compound represented by the general formula (I) is not provided, the electrical characteristics are deteriorated even when used repeatedly over a long period of time. A suppressed electrophotographic photoreceptor is obtained. In addition, an electrophotographic photosensitive member capable of achieving both a higher degree of curing and excellent charge transport performance than the case where the group represented by the general formula (IV-1) or (IV-2) is not included. can get. Moreover, compared with the case where it does not have the group represented by the general formula (V-1) or (V-2), it is possible to achieve both a higher degree of curing and excellent charge transport performance, particularly in charge transport performance. An excellent electrophotographic photoreceptor can be obtained.
According to the invention of claim 2, an electrophotographic photoreceptor excellent in charge transport performance can be obtained as compared with the case where the compound is not a polymer of the compound represented by the general formula (II). In addition, an electrophotographic photosensitive member capable of achieving both a higher degree of curing and excellent charge transport performance than the case where the group represented by the general formula (IV-1) or (IV-2) is not included. can get. Moreover, compared with the case where it does not have the group represented by the general formula (V-1) or (V-2), it is possible to achieve both a higher degree of curing and excellent charge transport performance, particularly in charge transport performance. An excellent electrophotographic photoreceptor can be obtained.

According to the invention of claim 3 , even when the charge transporting layer containing the polymer of the compound represented by the general formula (I) is not the outermost surface layer, the electrical characteristics are maintained even when used repeatedly over a long period of time. An electrophotographic photosensitive member in which the deterioration of the toner is further suppressed is obtained.
According to the fourth aspect of the present invention, an electrophotographic photosensitive member can be obtained in which deterioration of electrical characteristics is further suppressed even when used repeatedly over a long period of time, compared with a case where a thermal radical generator or derivative thereof is not included.

According to the inventions according to claims 5 and 6 , it is repeated over a long period of time as compared with a case where an electrophotographic photoreceptor provided with a charge transporting layer containing a polymer of the compound represented by the general formula (I) is not applied. A process cartridge and an image forming apparatus in which deterioration of image quality is suppressed even when used can be provided.

1 is a schematic partial cross-sectional view showing an electrophotographic photosensitive member according to an embodiment. 1 is a schematic partial cross-sectional view showing an electrophotographic photosensitive member according to an embodiment. 1 is a schematic partial cross-sectional view showing an electrophotographic photosensitive member according to an embodiment. 1 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment. It is a schematic block diagram which shows the image forming apparatus which concerns on other embodiment. (A) thru | or (C) are explanatory drawings which respectively show the reference | standard of ghost evaluation. It is IR spectrum data of exemplary compound CTM-39. It is IR spectrum data of exemplary compound CTM-40. It is IR spectrum data of exemplary compound CTM-44. It is IR spectrum data of exemplary compound CTM-45. It is IR spectrum data of exemplary compound CTM-46. It is IR spectrum data of exemplary compound CTM-71.

[Electrophotographic photoconductor]
The electrophotographic photoreceptor according to the exemplary embodiment is an electrophotographic photoreceptor provided with a charge transporting layer containing a polymer of a compound represented by the following general formula (I).

<Compound represented by formula (I)>
First, the compound represented by the following general formula (I) will be described.

  In the general formula (I), F represents a charge transporting subunit, L represents an alkylene group, -C = C-, -C (= O)-, -N (R)-, -O-, -S. -Represents an (n + 1) -valent linking group formed by combining two or more selected from the group consisting of a trivalent or tetravalent group derived from alkane or alkene, and R represents a hydrogen atom, an alkyl group, an aryl A group or an aralkyl group; m represents an integer of 1 to 6, and n represents an integer of 2 to 3.

The charge transporting subunit represented by F in the general formula (I) may be a subunit derived from a compound having charge transporting performance. Specifically, specifically, a phthalocyanine compound, porphyrin Compounds, azobenzene compounds, triarylamine compounds, benzidine compounds, arylalkane compounds, aryl-substituted ethylene compounds, stilbene compounds, anthracene compounds, hydrazone compounds, quinone compounds, fluorenone compounds, etc. Examples include subunits derived from compounds having charge transport performance.
Among them, a subunit derived from a triarylamine compound that is excellent in terms of charge mobility, oxidation stability, and the like is preferable.

Specific examples of the (n + 1) -valent linking group represented by L in the general formula (I) include an alkylene group, -C = C-, -C (= O)-, and -N (R )-, -O-, -S-, and a group selected from the group consisting of a trivalent or tetravalent group derived from alkane or alkene, and a trivalent or tetravalent group. The trivalent or tetravalent group derived from alkane or alkene means a group obtained by removing a hydrogen atom from alkane or alkene. The same applies hereinafter.
More specifically, in the case of a trivalent linking group, the following groups are exemplified. In the trivalent linking group shown below, “*” represents a site linked to F.
_{* - (CH 2) a-} CH [-C (= O) -O- (CH 2) b-] 2,
_{* - (CH 2) a-} CH [-CH 2 -O- (CH 2) b-] 2,
* -CH = C [-C (= O) -O- (CH 2) b-] 2,
_{* -CH = C [- (CH} 2) c-O- (CH 2) b-] 2,
_{* - (CH 2) a-} CH [-C (= O) -N (R) - (CH 2) b-] 2,
_{* - (CH 2) a-} CH [-C (= O) -S- (CH 2) b-] 2,
_{* - (CH 2) a-} CH [- (CH 2) c-N (R) - (CH 2) b-] 2,
_{* - (CH 2) a-} CH [- (CH 2) c-S- (CH 2) b-] 2,

_{* -O- (CH 2) d-} CH [- (CH 2) c-O- (CH 2) b-] 2,
_{* - (CH 2) f-} O- (CH 2) d-CH [- (CH 2) c-O- (CH 2) b-] 2
Here, in the above trivalent linking group, a, b, c, d, e, and f represent a repeating unit of a methylene group and represent an integer of 1 to 10 (preferably 1 to 4). .

  Further, when L is a tetravalent linking group, specific examples include the following groups. In the tetravalent linking group shown below, “*” indicates a site to be connected to F.

  Here, in the above tetravalent linking group, b, c, and g represent a repeating unit of a methylene group, and represent an integer of 1 to 10 (preferably 1 to 4).

In the linking group representing L in the general formula (I), the alkyl group represented by R of “—N (R) —” is a straight chain having 1 to 10 carbon atoms (preferably 1 to 5 carbon atoms), Examples include a branched alkyl group, and specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a butyl group, a t-butyl machine, and a pentyl group.
Examples of the aryl group represented by R of “—N (R) —” include aryl groups having 6 to 20 carbon atoms (preferably 6 to 12 carbon atoms). Specific examples thereof include a phenyl group and a toluyl group. , Xylyl group, cumenyl group, mesityl group, naphthyl group and the like.
Examples of the aralkyl group include aralkyl groups having 7 to 20 carbon atoms (preferably 7 to 14 carbon atoms). Specific examples thereof include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naltylethyl group. Is mentioned.

Examples of the positional relationship between L and the vinyl group bonded to the aromatic ring in the general formula (I) include a meta position and a para position. In the general formula (I), there are a plurality of aromatic rings. In the plurality of aromatic rings, the bonding positional relationship between L and the vinyl group may be only in the meta position or only in the para position, Para positions may be mixed.
Among them, a mixture is preferable from the viewpoint of solubility, and from the viewpoint of manufacturability of the charge transfer agent, purification by recrystallization is often possible. In particular, the para form is preferred.

  In general formula (I), m is an integer of 1 or more and 6 or less, and m is preferably 1 or more and 3 or less from the viewpoint of improving the charge transport performance, and 2 or more and 6 or less for increasing the strength. There should be.

  The novel compound according to this embodiment is particularly preferably a compound having a charge transporting subunit derived from a triarylamine-based compound as F in the general formula (I). Specifically, a compound represented by the following general formula (II) is desirable.

In the general formula (II), Ar ^{1 to} Ar ⁴ each independently represents a substituted or unsubstituted aryl group, Ar ⁵ represents a substituted or unsubstituted aryl group, or a substituted or unsubstituted arylene group, and D Represents a group represented by the general formula (III). k represents 0 or 1, c1 to c5 each represents an integer of 0 to 2, and c1 to c5 do not all become 0 at the same time.
In the general formula (III), L is derived from an alkylene group, -C = C-, -C (= O)-, -N (R)-, -O-, -S-, and an alkane or alkene. An (n + 1) -valent linking group formed by combining two or more selected from the group consisting of trivalent or tetravalent groups, and R represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. n represents an integer of 2 or more and 3 or less.

The substituted or unsubstituted aryl groups represented by Ar ^{1 to} Ar ⁴ in the general formula (II) may be the same or different.
Here, as a substituent in the substituted aryl group, other than “(D) _C ”, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, and 1 to 4 carbon atoms. Examples include a phenyl group substituted with an alkoxy group, an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, and a halogen atom.
Ar ^{1 to} Ar ⁴ are preferably any one of the following structural formulas (1) to (7). In addition, the following structural formulas (1) to (7) collectively indicate “— (D) _C1 ” to “— (D) _C4 ” that can be connected to each Ar ^{1 to} Ar ^4. _C ".

In the structural formula (1), R ⁹ is a phenyl group substituted with a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. , An unsubstituted phenyl group, and one selected from the group consisting of an aralkyl group having 7 to 10 carbon atoms.
In the structural formulas (2) and (3), R ^{10 to} R ¹² are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or 1 or more carbon atoms. 1 type selected from the group consisting of a phenyl group substituted with 4 or less alkoxy groups, an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, and a halogen atom. T represents an integer of 1 or more and 3 or less. In the structural formula (7), Ar represents a substituted or unsubstituted arylene group.
Here, as Ar in Formula (7), what is represented by following Structural formula (8) or (9) is desirable.

In the structural formulas (8) and (9), R ¹³ and R ¹⁴ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or 1 or more carbon atoms. 1 represents one selected from the group consisting of a phenyl group substituted with 4 or less alkoxy groups, an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, and a halogen atom, and t is an integer of 1 to 3 Represents.
In the structural formula (7), Z ′ represents a divalent organic linking group, and is preferably represented by any one of the following structural formulas (10) to (17). S represents 0 or 1 respectively.

In the structural formulas (10) to (17), R ¹⁵ and R ¹⁶ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or 1 or more carbon atoms. 1 represents one selected from the group consisting of a phenyl group substituted with 4 or less alkoxy groups, an unsubstituted phenyl group, an aralkyl group having 7 to 10 carbon atoms, and a halogen atom, and W represents a divalent group. , Q and r each independently represent an integer of 1 to 10, and t represents an integer of 1 to 3.
W in the structural formulas (16) to (17) is preferably any one of divalent groups represented by the following (18) to (26). However, in formula (25), u represents an integer of 0 or more and 3 or less.

Ar ⁵ in the general formula (II) is a substituted or unsubstituted aryl group when k is 0, and examples of the aryl group include the aryl groups exemplified in the description of Ar ^{1 to} Ar ^4. It is done. When k is 1, Ar ⁵ is a substituted or unsubstituted arylene group. The arylene group includes an arylene group obtained by removing one hydrogen atom from the aryl group exemplified in the description of Ar ^{1 to} Ar ^4. Is mentioned.
Further, the substituent in the substituted arylene group is the same as the substituents other than “D” in the substituted aryl group in the description of Ar ^{1 to} Ar ⁴ .

  L in the group represented by the general formula (III) represented by D in the general formula (II) is synonymous with L in the description of the general formula (I), and each specifically exemplified group is desirable. It is mentioned as a thing.

  C1 to c5 in the general formula (II) each represent an integer of 0 to 2, and all of c1 to c5 do not become 0 at the same time. That is, it means that the total number of D in the general formula (II) is 1 or more, and the total number of D is preferably 1 or more and 4 or less.

Next, a structure desirable as a group represented by the following partial structure and the general formula (III) in the general formula (I) will be described.
As the group represented by the following partial structure and general formula (III), the group represented by the following general formula (IV-1), the group represented by the general formula (IV-2), the following general formula (V- The group represented by 1) or the group represented by the general formula (V-2) is desirable from the viewpoint of achieving both electrical properties and a curing degree.

In general formulas (IV-1) and (IV-2), X represents a single bond or a linking group, and p represents 0 or 1.
In general formulas (V-1) and (V-2), X ′ represents a single bond or a linking group, and p ′ represents 0 or 1.
In the partial structure, the wavy line indicates the binding site with the charge transporting subunit indicated by F.

  Examples of the linking group represented by X and X ′ include —C═, an alkylene group having 1 or more carbon atoms, —C═C—, —C (═O) —, —N (R) —, —O—. , And -S-, or a group in which two or more of these are combined.

Specific examples of the compound represented by the general formula (I) are shown below. In addition, the compound represented with general formula (I) is not limited at all by these.
First, specific examples of the charge transporting subunit (skeleton excluding the partial structure) represented by F in the general formula (I) and specific examples of the partial structure (group represented by the general formula (III)) Thereafter, these combinations are described in Table 1 and Table 2, and this was taken as a specific example (exemplary compound) of the compound represented by the general formula (I).
In the following specific examples, “*” means a linking site. Here, in the exemplary compounds described in Table 1, compound No. CTM-1 is a specific example of a charge transporting subunit represented by F (described as “skeleton” in Table 1): (1) -1 and the partial structure (represented by the general formula (III)) Specific examples of the group (described as “functional group” in Table 1): (III) -1 and a compound connected by “*”. Specifically, CTM-1 shows the following structure.

Next, a method for synthesizing the compound represented by the general formula (I) will be described.
For the synthesis of the compound represented by the general formula (I), those used for the synthesis and reaction of the following general charge transport materials can be applied. Specifically, the methods listed in the examples can be used.
Formylation: A reaction suitable for introducing a formyl group into an aromatic compound, heterocyclic compound or alkene having an electron donating group. DMF and phosphorus oxytrichloride are generally used, and the reaction temperature is often from room temperature to about 100 ° C.
Esterification: A condensation reaction between an organic acid and a compound containing a hydroxyl group such as alcohol or phenol. It is preferable to use a method of biasing the equilibrium toward the ester side by coexisting a dehydrating agent or removing water out of the system.
Etherification: A Williamson synthesis method in which an alkoxide and an organic halogen compound are condensed is common.
Hydrogenation: A method in which hydrogen is reacted with an unsaturated bond using various catalysts.

The compound represented by the general formula (I) according to this embodiment includes two or three chain-polymerizable reactive groups (styrene) through one linking group L from the charge transporting subunit represented by F. Group).
Detailed investigations by the present inventors have revealed that the charge transport performance deteriorates when the degree of cure of the charge transport compound, that is, the number of cross-linking sites is increased. The cause is not necessarily clear, but at this stage, if the degree of cure of the charge transporting compound, that is, the number of cross-linking sites is increased, the charge transporting sites (charge transporting subunits) are distorted when cured (cross-linked). I guess it is because it occurs.
However, since the compound represented by the general formula (I) has a structure having two or three chain polymerizable reactive groups via one linking group L, it maintains a high degree of curing and the number of crosslinking sites. However, the presence of the linking group L makes it difficult to generate distortion in the charge transporting subunit when cured (cross-linked), and it is possible to achieve both a high degree of curing and excellent charge transport performance.
In addition, conventionally used charge transporting compounds having a (meth) acryl group are likely to be distorted as described above, and the reactive sites are highly hydrophilic and the charge transporting sites are highly hydrophobic. Therefore, the compound represented by the general formula (I) has a styrene group as a reactive group, and further has a charge transporting moiety ( It has a structure having a linking group L that is difficult to cause distortion in the charge transporting subunit), and the reactive site and the charge transporting site are both hydrophobic, so that phase separation is difficult to occur. It is thought that charge transport performance and high strength can be achieved. As a result, the charge transporting layer containing the polymer of the compound represented by the general formula (I) is considered to be excellent in mechanical strength and charge transport performance (electrical characteristics).

<Electrophotographic photoreceptor>
The electrophotographic photoreceptor according to the exemplary embodiment includes a charge transporting layer including at least a polymer of the compound represented by the general formula (I).
As described above, since the compound represented by the general formula (I) can form a charge transporting layer excellent in both mechanical strength and charge transporting performance, an electrophotographic image to which this charge transporting layer is applied. Even if the photoreceptor is used repeatedly over a long period of time, it is considered that deterioration of electrical characteristics is suppressed, and as a result, stable images can be continuously obtained.
In particular, the charge transporting layer may have high mechanical strength, and is preferably applied to the outermost surface layer of the electrophotographic photosensitive member. Even in this configuration, the charge transporting layer may be used repeatedly over a long period of time. It is considered that deterioration of electrical characteristics is suppressed, and as a result, stable images can be continuously obtained.

The polymer contained in the charge transporting layer can be obtained by polymerizing the compound represented by the general formula (I) with energy such as heat, light, and electron beam.
In addition, the charge transporting layer containing this polymer is prepared by preparing a composition containing the compound represented by the general formula (I) and other components as required, and applying the composition to heat, light, It is obtained by polymerizing (curing) with energy such as an electron beam.

The content of the polymer of the compound represented by the general formula (I) in the charge transporting layer according to the present embodiment is set based on the charge transporting performance according to the use of the charge transporting layer. In general, the charge transporting layer may be set in the range of 5 mass% to 100 mass% (desirably 40 mass% to 100 mass%).
In addition, in the charge transport layer according to the present embodiment, in addition to the polymer of the compound represented by the general formula (I), the compound itself represented by the general formula (I) (unreacted state) is contained. May be.

The charge transporting layer in the electrophotographic photoreceptor according to the exemplary embodiment has a functional number of the chain polymerizable functional group in the compound represented by the general formula (I), that is, the partial structure (general formula (III) You may adjust the intensity | strength of a charge transportable layer (cured material), without reducing charge transport performance by using together what differs in the number of group represented.
Specifically, the compound represented by the general formula (III) has a functional group number of 2 or more for the purpose of adjusting the strength of the charge transporting layer (cured product) without reducing the charge transport performance. A compound and a compound having a smaller number of functional groups may be used in combination.
In such a combination, the content of the compound having 2 or more functional groups is 5% by mass to 95% by mass (preferably 10% by mass to 90% by mass) of the total content of the compound represented by the general formula (III). (Mass% or less) may be set.

  The electrophotographic photoreceptor according to the exemplary embodiment includes the charge transporting layer according to the exemplary embodiment, and the charge transporting layer may be any of the outermost surface layer and a layer other than the outermost surface layer. However, as described above, the outermost surface layer is preferable because it is excellent in both mechanical strength and charge transport performance.

Here, the outermost surface layer forms the uppermost surface of the electrophotographic photosensitive member itself, and is desirably provided as a layer functioning as a protective layer or a layer functioning as a charge transport layer.
In the case where the outermost surface layer is a layer functioning as a protective layer, the photosensitive layer and the protective layer as the outermost surface layer are provided on the conductive substrate, and the protective layer includes the charge transporting layer described above. It is done.
On the other hand, in the case where the outermost surface layer is a layer that functions as a charge transport layer, it has a charge generation layer and a charge transport layer as the outermost surface layer on the conductive substrate, and the charge transport layer is the charge transport layer described above. The form comprised is mentioned.
In the case where the above-described charge transporting layer constitutes a layer other than the outermost surface layer, a protective layer as an outermost surface layer is formed on the photosensitive layer together with the photosensitive layer including the charge generating layer and the outermost surface layer on the conductive substrate. And the charge transport layer is composed of the above-described charge transport layer.

Hereinafter, the electrophotographic photoreceptor according to the exemplary embodiment in the case where the above-described charge transporting layer is a layer functioning as a protective layer which is the outermost surface layer will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.
FIG. 1 is a schematic cross-sectional view showing a preferred embodiment of the electrophotographic photoreceptor according to the embodiment. 2 to 3 are schematic sectional views showing electrophotographic photosensitive members according to other embodiments.

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

  The electrophotographic photoreceptor 7B shown in FIG. 2 is a function-separated type photoreceptor in which the functions are separated into the charge generation layer 2 and the charge transport layer 3 like the electrophotographic photoreceptor 7A shown in FIG. 3 includes the charge generation material and the charge transport material in the same layer (single-layer type photosensitive layer 6 (charge generation / charge transport layer)).

In the electrophotographic photoreceptor 7B shown in FIG. 2, a structure in which an undercoat layer 1 is provided on a conductive substrate 4, and a charge transport layer 3, a charge generation layer 2, and a protective layer 5 are sequentially formed thereon. It is what has. In the electrophotographic photoreceptor 7B, a photosensitive layer is constituted by the charge transport layer 3 and the charge generation layer 2.
Further, the electrophotographic photoreceptor 7C shown in FIG. 3 has a structure in which the undercoat layer 1 is provided on the conductive substrate 4, and the single-layer type photosensitive layer 6 and the protective layer 5 are sequentially formed thereon. It is.

In the electrophotographic photoreceptors 7A to 7C shown in FIGS. 1 to 3, the protective layer 5 is the outermost surface layer disposed on the side farthest from the conductive substrate 2, and the outermost surface layer is It is the structure comprised by the electric charge transportable layer mentioned above.
In the electrophotographic photoreceptor shown in FIGS. 1 to 3, the undercoat layer 1 may or may not be provided.

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

(Conductive substrate)
Any conductive substrate may be used as long as it is conventionally used. For example, thin films (eg, metals such as aluminum, nickel, chromium, stainless steel, and films of aluminum, titanium, nickel, chromium, stainless steel, gold, vanadium, tin oxide, indium oxide, indium tin oxide (ITO), etc.) And a plastic film coated or impregnated with a conductivity-imparting agent, a plastic film coated or impregnated with a conductivity-imparting agent, and the like. The shape of the substrate is not limited to a cylindrical shape, and may be a sheet shape or a plate shape.
Note that the conductive substrate preferably has a conductivity of, for example, a volume resistivity of less than 10 ⁷ Ω · cm.

  When a metal pipe is used as the conductive substrate, the surface may be left as it is, and treatments such as mirror cutting, etching, anodizing, rough cutting, centerless grinding, sand blasting, and wet honing have been performed in advance. Also good.

(Undercoat layer)
The undercoat layer is provided as necessary for the purpose of preventing light reflection on the surface of the conductive substrate and preventing inflow of unnecessary carriers from the conductive substrate to the photosensitive layer.

The undercoat layer includes, for example, a binder resin and, if necessary, other additives.
As the binder resin contained in the undercoat layer, acetal resins such as polyvinyl butyral, polyvinyl alcohol resin, casein, polyamide resin, cellulose resin, gelatin, polyurethane resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, Known polymer resin compounds such as polyvinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone-alkyd resin, phenol resin, phenol-formaldehyde resin, melamine resin, urethane resin, and charge transporting group Examples thereof include charge transporting resins having a conductive resin such as polyaniline. Among these, resins that are insoluble in the upper coating solvent are preferably used, and phenol resins, phenol-formaldehyde resins, melamine resins, urethane resins, epoxy resins, and the like are particularly preferably used.

  The undercoat layer may contain a metal compound such as a silicon compound, an organic zirconium compound, an organic titanium compound, or an organic aluminum compound.

  The ratio between the metal compound and the binder resin is not particularly limited, and is set within a range in which desired electrophotographic photoreceptor characteristics can be obtained.

  Resin particles may be added to the undercoat layer in order to adjust the surface roughness. Examples of the resin particles include silicone resin particles and cross-linked polymethyl methacrylate (PMMA) resin particles. The surface may be polished after forming the undercoat layer for adjusting the surface roughness. As a polishing method, buffing, sandblasting, wet honing, grinding, or the like is used.

Here, the structure of the undercoat layer includes a structure containing at least a binder resin and conductive particles. Note that the conductive particles preferably have conductivity with a volume resistivity of less than 10 ⁷ Ω · cm, for example.

Examples of the conductive particles include metal particles (particles such as aluminum, copper, nickel, and silver), conductive metal oxide particles (particles such as antimony oxide, indium oxide, tin oxide, and zinc oxide), and conductive substance particles. (Carbon fiber, carbon black, particles of graphite powder) and the like. Among these, conductive metal oxide particles are preferable. You may mix and use 2 or more types of electroconductive particle.
In addition, the conductive particles may be subjected to a surface treatment with a hydrophobizing agent (for example, a coupling agent) or the like to adjust the resistance.
For example, the content of the conductive particles is preferably 10% by mass or more and 80% by mass or less, and more preferably 40% by mass or more and 80% by mass or less with respect to the binder resin.

In forming the undercoat layer, a coating solution for forming an undercoat layer in which the above components are added to a solvent is used.
In addition, as a method for dispersing particles in the coating solution for forming the undercoat layer, a media disperser such as a ball mill, a vibrating ball mill, an attritor, a sand mill, a horizontal sand mill, an agitator, an ultrasonic disperser, a roll mill, a high-pressure homogenizer, etc. Medialess dispersers are used. Here, examples of the high-pressure homogenizer include a collision method in which the dispersion liquid is dispersed by liquid-liquid collision or liquid-wall collision in a high-pressure state, and a penetration method in which a fine flow path is dispersed in a high-pressure state. .

  Examples of the method for applying the coating liquid for forming the undercoat layer onto the conductive substrate include dip coating, push-up coating, wire bar coating, spray coating, blade coating, knife coating, and curtain coating. It is done.

  The thickness of the undercoat layer is preferably 15 μm or more, and more preferably 20 μm or more and 50 μm or less.

  Here, although not shown, an intermediate layer may be further provided between the undercoat layer and the photosensitive layer. As the binder resin used for the intermediate layer, acetal resins such as polyvinyl butyral, polyvinyl alcohol resin, casein, polyamide resin, cellulose resin, gelatin, polyurethane resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinyl In addition to polymer resins such as acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, melamine resin, zirconium, titanium, aluminum, manganese, silicon atom, etc. An organometallic compound containing These compounds may be used alone or as a mixture or polycondensate of a plurality of compounds. Among these, an organometallic compound containing zirconium or silicon is preferable in that it has a low residual potential, a small potential change due to the environment, and a small potential change due to repeated use.

In forming the intermediate layer, a coating solution for forming an intermediate layer in which the above components are added to a solvent is used.
As the coating method for forming the intermediate layer, usual methods such as a dip coating method, a push-up coating method, a wire bar coating method, a spray coating method, a blade coating method, a knife coating method, and a curtain coating method are used.

  In addition to improving the coatability of the upper layer, the intermediate layer also serves as an electrical blocking layer. However, if the film thickness is too large, the electrical barrier becomes too strong and the potential increases due to desensitization or repetition. May cause. Therefore, when forming the intermediate layer, it is preferable to set the film thickness within the range of 0.1 μm to 3 μm. In this case, the intermediate layer may be used as the undercoat layer.

(Charge generation layer)
The charge generation layer includes, for example, a charge generation material and a binder resin. Examples of such a charge generating material include phthalocyanine pigments such as metal-free phthalocyanine, chlorogallium phthalocyanine, hydroxygallium phthalocyanine, dichlorotin phthalocyanine, and titanyl phthalocyanine. A chlorogallium phthalocyanine crystal having strong diffraction peaks at least at 7.4 °, 16.6 °, 25.5 ° and 28.3 °, a Bragg angle (2θ ± 0.2 °) to CuKα characteristic X-ray of at least 7 Metal-free phthalocyanine crystals having strong diffraction peaks at .7 °, 9.3 °, 16.9 °, 17.5 °, 22.4 °, and 28.8 °, Bragg angle (2θ ± 0) with respect to CuKα characteristic X-rays .2 °) at least 7.5 °, 9.9 °, 12.5 °, 16.3 °, 18.6 ° Hydroxygallium phthalocyanine crystals having strong diffraction peaks at 25.1 ° and 28.3 °, Bragg angles (2θ ± 0.2 °) with respect to CuKα characteristic X-rays of at least 9.6 °, 24.1 ° and 27.2 A titanyl phthalocyanine crystal having a strong diffraction peak at 0 ° can be mentioned. In addition, examples of the charge generation material include quinone pigments, perylene pigments, indigo pigments, bisbenzimidazole pigments, anthrone pigments, quinacridone pigments, and the like. These charge generation materials may be used alone or in combination of two or more.

Examples of the binder resin constituting the charge generation layer include polycarbonate resin such as bisphenol A type or bisphenol Z type, acrylic resin, methacrylic resin, polyarylate resin, polyester resin, polyvinyl chloride resin, polystyrene resin, acrylonitrile-styrene. Copolymer resin, acrylonitrile-butadiene copolymer, polyvinyl acetate resin, polyvinyl formal resin, polysulfone resin, styrene-butadiene copolymer resin, vinylidene chloride-acrylonitrile copolymer resin, vinyl chloride-vinyl acetate-maleic anhydride Examples thereof include resins, silicone resins, phenol-formaldehyde resins, polyacrylamide resins, polyamide resins, poly-N-vinylcarbazole resins. These binder resins may be used alone or in combination of two or more.
The mixing ratio of the charge generating material and the binder resin is preferably in the range of 10: 1 to 1:10, for example.

  When forming the charge generation layer, a coating solution for forming a charge generation layer in which the above components are added to a solvent is used.

  As a method for dispersing particles (for example, charge generation material) in the coating solution for forming the charge generation layer, a media dispersion machine such as a ball mill, a vibration ball mill, an attritor, a sand mill, a horizontal sand mill, an agitation, an ultrasonic dispersion machine, a roll mill, etc. Medialess dispersers such as high-pressure homogenizers are used. Examples of the high-pressure homogenizer include a collision method in which the dispersion liquid is dispersed by liquid-liquid collision or liquid-wall collision in a high-pressure state, and a penetration method in which a fine flow path is dispersed in a high-pressure state.

  Examples of the method for applying the charge generation layer forming coating liquid on the undercoat layer include dip coating, push-up coating, wire bar coating, spray coating, blade coating, knife coating, and curtain coating. It is done.

  The thickness of the charge generation layer is desirably set in the range of 0.01 μm to 5 μm, more desirably 0.05 μm to 2.0 μm.

(Charge transport layer)
The charge transport layer includes a charge transport material and, if necessary, a binder resin.

  Examples of the charge transporting material include oxadiazole derivatives such as 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole, 1,3,5-triphenyl-pyrazoline, 1- [Pyridyl- (2)]-3- (p-diethylaminostyryl) -5- (p-diethylaminostyryl) pyrazoline and other pyrazoline derivatives, triphenylamine, N, N′-bis (3,4-dimethylphenyl) biphenyl Aromatic tertiary amino compounds such as -4-amine, tri (p-methylphenyl) aminyl-4-amine, dibenzylaniline, N, N'-bis (3-methylphenyl) -N, N'-diphenyl Aromatic tertiary diamino compounds such as benzidine, 3- (4′-dimethylaminophenyl) -5,6-di- (4′-methoxyphenyl) -1,2, -1,2,4-triazine derivatives such as triazine, hydrazone derivatives such as 4-diethylaminobenzaldehyde-1,1-diphenylhydrazone, quinazoline derivatives such as 2-phenyl-4-styryl-quinazoline, 6-hydroxy-2,3 Benzofuran derivatives such as -di (p-methoxyphenyl) benzofuran, α-stilbene derivatives such as p- (2,2-diphenylvinyl) -N, N-diphenylaniline, enamine derivatives, carbazole derivatives such as N-ethylcarbazole, Hole transport materials such as poly-N-vinylcarbazole and derivatives thereof, quinone compounds such as chloranil and broanthraquinone, tetraanoquinodimethane compounds, 2,4,7-trinitrofluorenone, 2,4,5, Fluoreno such as 7-tetranitro-9-fluorenone And an electron transport material such as a thiophene compound, a xanthone compound, and a thiophene compound, and a polymer having a group consisting of the above-described compounds in the main chain or side chain. These charge transport materials may be used alone or in combination of two or more.

Examples of the binder resin constituting the charge transport layer include polycarbonate resin such as bisphenol A type or bisphenol Z type, acrylic resin, methacrylic resin, polyarylate resin, polyester resin, polyvinyl chloride resin, polystyrene resin, acrylonitrile-styrene. Copolymer resin, acrylonitrile-butadiene copolymer resin, polyvinyl acetate resin, polyvinyl formal resin, polysulfone resin, styrene-butadiene copolymer resin, vinylidene chloride-acrylonitrile copolymer resin, vinyl chloride-vinyl acetate-anhydrous maleic acid Insulating resins such as acid resins, silicone resins, phenol-formaldehyde resins, polyacrylamide resins, polyamide resins, and chlorinated rubber, and polyvinylcarbazole and polyvinylanthraces And organic photoconductive polymers such as polyvinyl pyrene, and the like. These binder resins may be used alone or in combination of two or more.
The mixing ratio between the charge transporting material and the binder resin is preferably 10: 1 to 1: 5, for example.

  The charge transport layer is formed using a charge transport layer forming coating solution in which the above components are added to a solvent.

  As a method for dispersing particles (for example, fluororesin particles) in the coating liquid for forming the charge transport layer, a media dispersing machine such as a ball mill, a vibrating ball mill, an attritor, a sand mill, a horizontal sand mill, a stirring, an ultrasonic dispersing machine, a roll mill, etc. Medialess dispersers such as high-pressure homogenizers are used. Examples of the high-pressure homogenizer include a collision method in which the dispersion liquid is dispersed by liquid-liquid collision or liquid-wall collision in a high-pressure state, and a penetration method in which a fine flow path is dispersed in a high-pressure state.

Examples of methods for applying the charge transport layer forming coating solution onto the charge generation layer include dip coating, push-up coating, wire bar coating, spray coating, blade coating, knife coating, and curtain coating. The usual method is used.
The film thickness of the charge transport layer is desirably set in the range of 5 μm to 50 μm, more desirably 10 μm to 40 μm.

(Protective layer)
The protective layer is obtained by applying the above-described charge transporting layer, and contains a polymer of the compound represented by the general formula (I).
In forming this protective layer, a charge transporting composition containing the compound represented by the general formula (I) is used, and the total content of the compound represented by the general formula (I) is the charge transporting composition. For example, 40% by mass or more is desirable, more desirably 50% by mass or more, and still more desirably 60% by mass or more with respect to the product (total solid content mass excluding the solvent).
By setting it as this range, it is excellent in an electrical property and thickness of the cured film is implement | achieved.

Moreover, in this embodiment, you may use together the compound represented with general formula (I), and the well-known charge transport material which does not have a reactive group. Known charge transporting materials that do not have reactive groups are effective because they do not have reactive groups that do not carry charge transport, increasing the component concentration of charge transporting materials and further improving electrical properties. is there.
As this known charge transporting material, those mentioned as the charge transporting material constituting the charge transporting layer are used.

Hereinafter, other components of the charge transporting composition for forming the protective layer will be described.
The charge transporting composition used for forming the protective layer may contain the following surfactant from the viewpoint of ensuring film forming properties.

Examples of the surfactant include (A) a structure formed by polymerizing an acrylic monomer having a fluorine atom, (B) a structure having a carbon-carbon double bond and a fluorine atom, (C) an alkylene oxide structure, and (D) carbon. -A surfactant containing in the molecule thereof one or more types of structures having a carbon triple bond and a hydroxyl group.
This surfactant needs to contain 1 or more types of the structure of (A) thru | or (D) in the molecule | numerator, and may contain 2 or more types.

  Hereinafter, the structures (A) to (D) and the surfactant having the structure will be described.

(A) Structure formed by polymerizing an acrylic monomer having a fluorine atom (A) The structure formed by polymerizing an acrylic monomer having a fluorine atom is not particularly limited, but an acrylic monomer having a fluoroalkyl group is polymerized. The structure is preferably a structure obtained by polymerizing an acrylic monomer having a perfluoroalkyl group.

  Specific examples of the surfactant having the structure (A) include Polyflow KL-600 (manufactured by Kyoeisha Chemical Co., Ltd.), F-top EF-351, EF-352, EF-801, EF-802, and EF- 601 (manufactured by JEMCO).

(B) Structure having a carbon-carbon double bond and a fluorine atom (B) The structure having a carbon-carbon double bond and a fluorine atom is not particularly limited, but in the following structural formulas (B1) and (B2) It is desirable that the group be at least one of them.

As the surfactant having the structure (B), a compound having a group represented by at least one of the structural formulas (B1) and (B2) in the side chain of the acrylic polymer, or the following structural formulas (B3) to (B3) to The compound represented by any one of (B5) is desirable.
When the surfactant having the structure (B) is a compound having at least one of the structural formulas (B1) and (B2) in the side chain of the acrylic polymer, the acrylic structure and the other components in the composition A uniform outermost surface layer can be formed because of the familiarity.
In addition, when the surfactant having the structure (B) is a compound represented by any one of the structural formulas (B3) to (B5), it tends to prevent repelling during coating. Defects can be suppressed.

In the structural formulas (B3) to (B5), v and w each independently represent an integer of 1 or more, R ′ represents a hydrogen atom or a monovalent organic group, and Rf each independently represents a structural formula (B1). Or represents the group shown by (B2).
In the structural formulas (B3) to (B5), examples of the monovalent organic group represented by R ′ include an alkyl group having 1 to 30 carbon atoms and a hydroxyalkyl group having 1 to 30 carbon atoms.

The following are mentioned as a commercial item of surfactant which has the structure of (B).
For example, as a compound represented by any one of structural formulas (B3) to (B5), the following are possible: 100, 100C, 110, 140A, 150, 150CH, AK, 501, 250, 251, 222F, FTX-218, 300, 310, 400SW, 212M, 245M, 290M, FTX-207S, FTX-211S, FTX-220S, FTX-230S, FTX-209F, FTX-213F, FTX-222F, FTX-233F, FTX-245F, FTX- 208G, FTX-218G, FTX-230G, FTX-240G, FTX-204D, FTX-280D, FTX-212D, FTX-216D, FTX-218D, FTX-220D (manufactured by Neos Corporation), etc. It is done.
Moreover, as a compound which has at least one of Structural formula (B1) and (B2) in the side chain of an acrylic polymer, KB-L82, KB-L85, KB-L97, KB-L109, KB-L110, KB-F2L , KB-F2M, KB-F2S, KB-F3M, KB-FaM (manufactured by Neos Corporation) and the like.

-(C) alkylene oxide structure (C) As an alkylene oxide structure, an alkylene oxide and a polyalkylene oxide are included. Specific examples of the alkylene oxide include ethylene oxide and propylene oxide, and the alkylene oxide may be a polyalkylene oxide having a repeating number of 2 to 10,000.
Examples of the surfactant (C) having an alkylene oxide structure include polyethylene glycol, polyether antifoaming agent, and polyether-modified silicone oil.
The polyethylene glycol preferably has an average molecular weight of 2000 or less, and the polyethylene glycol having an average molecular weight of 2000 or less includes polyethylene glycol 2000 (average molecular weight 2000), polyethylene glycol 600 (average molecular weight 600), polyethylene glycol 400 (average molecular weight). 400), polyethylene glycol 200 (average molecular weight 200), and the like.
In addition, PE-M, PE-L (above, manufactured by Wako Pure Chemical Industries, Ltd.), antifoam No. 1. Antifoaming agent No. 1 Polyether antifoaming agents such as 5 (above, manufactured by Kao Corporation) are also suitable examples.

(C) As the surfactant containing a fluorine atom in the molecule in addition to the alkylene oxide structure, those having an alkylene oxide or polyalkylene oxide in the side chain of the polymer having a fluorine atom, and alkylene oxide or polyalkylene oxide Examples thereof include those in which the terminal is substituted with a substituent containing a fluorine atom.
(C) Specific examples of surfactants containing a fluorine atom in the molecule in addition to the alkylene oxide structure include, for example, Megafac F-443, F-444, F-445, F-446 (and above, Dainippon Ink, Inc.). Chemical Industry Co., Ltd.), Footgent 250, 251, 222F (above, manufactured by Neos), POLY FOX PF636, PF6320, PF6520, PF656 (above, made by Kitamura Chemical Co., Ltd.).

  (C) Specific examples of the surfactant containing a silicone structure in the molecule in addition to the alkylene oxide structure include KF351 (A), KF352 (A), KF353 (A), KF354 (A), KF355 (A ), KF615 (A), KF618, KF945 (A), KF6004 (manufactured by Shin-Etsu Chemical Co., Ltd.), TSF4440, TSF4445, TSF4450, TSF4446, TSF4452, TSF4453, TSF4460 (manufactured by GE Toshiba Silicon Corporation), BYK- 300, 302, 306, 307, 310, 315, 320, 322, 323, 325, 330, 331, 333, 337, 341, 344, 345, 346, 347, 348, 370, 375, 377, 378, UV3500, UV3510, UV3570, etc. (above, Kkukemi Japan Co., Ltd.) and the like.

-(D) Structure having a carbon-carbon triple bond and a hydroxyl group (D) The structure having a carbon-carbon triple bond and a hydroxyl group is not particularly limited, and examples of the surfactant having this structure include the following compounds. It is done.
(D) Examples of the surfactant having a structure having a carbon-carbon triple bond and a hydroxyl group include compounds having a triple bond and a hydroxyl group in the molecule. Specifically, for example, 2-propyn-1-ol, 1-butyn-3-ol, 2-butyn-1-ol, 3-butyn-1-ol, 1-pentyn-3-ol, 2-pentyn-1-ol, 3-pentyn-1-ol, 4- Pentyn-1-ol, 4-pentyn-2-ol, 1-hexyn-3-ol, 2-hexyn-1-ol, 3-hexyn-1-ol, 5-hexyn-1-ol, 5-hexyne- 3-ol, 1-heptin-3-ol, 2-heptin-1-ol, 3-heptin-1-ol, 4-heptin-2-ol, 5-heptin-3-ol, 1-octin-3- All, 1-o Chin-3-ol, 3-octyn-1-ol, 3-nonin-1-ol, 2-decyn-1-ol, 3-decyn-1-ol, 10-undecin-1-ol, 3-methyl- 1-butyn-3-ol, 3-methyl-1-penten-4-in-3-ol, 3-methyl-1-pentyn-3-ol, 5-methyl-1-hexyn-3-ol, 3- Ethyl-1-pentyn-3-ol, 3-ethyl-1-heptin-3-ol, 4-ethyl-1-octin-3-ol, 3,4-dimethyl-1-pentyn-3-ol, 3, 5-dimethyl-1-hexyn-3-ol, 3,6-dimethyl-1-heptin-3-ol, 2,2,8,8-tetramethyl-3,6-nonadiin-5-ol, 4,6 -Nonadecadiin-1-ol, 10,12-pe Tacosadin-1-ol, 2-butyne-1,4-diol, 3-hexyne-2,5-diol, 2,4-hexadiyne-1,6-diol, 2,5-dimethyl-3-hexyne-2, 5-diol, 3,6-dimethyl-4-octyne-3,6-diol, 2,4,7,9-tetramethyl-5-decyne-4,7-diol, (+)-1,6-bis (2-Chlorophenyl) -1,6-diphenyl-2,4-hexadiyne-1,6-diol, (-)-1,6-bis (2-chlorophenyl) -1,6-diphenyl-2,4-hexadiyne -1,6-diol, 2-butyne-1,4-diol bis (2-hydroxyethyl), 1,4-diacetoxy-2-butyne, 4-diethylamino-2-butyn-1-ol, 1,1-diphenyl -2-Propin 1-ol, 1-ethynyl-1-cyclohexanol, 9-ethynyl-9-fluorenol, 2,4-hexadiindiyl-1,6-bis (4-phenylazobenzenesulfonate), 2-hydroxy-3- Butynoic acid, 2-hydroxy-3-butynoic acid ethyl ester, 2-methyl-4-phenyl-3-butyn-2-ol, methyl propargyl ether, 5-phenyl-4-pentyn-1-ol, 1-phenyl- 1-propyn-3-ol, 1-phenyl-2-propyne-1-ol, 4-trimethylsilyl-3-butyn-2-ol, 3-trimethylsilyl-2-propyne-1-ol and the like can be mentioned.
Moreover, the compound (For example, Surfynol 400 series (made by Shin-Etsu Chemical Co., Ltd.) etc.) which alkylene oxides, such as ethylene oxide, added to a part or all of the hydroxyl group of said compound are mentioned.

  (D) As the surfactant having a structure having a carbon-carbon triple bond and a hydroxyl group, a compound represented by any one of the following general formulas (D1) and (D2) is desirable.

In the general formulas (D1) and (D2), R ^a , R ^b , R ^c , and R ^d each independently represent a monovalent organic group, and x, y, and z are each independently An integer of 1 or more is shown.
Among the compounds represented by the general formula (D1) or (D2), those in which R ^a , R ^b , R ^c and R ^d are alkyl groups are preferable. More preferably, at least one of R ^a and R ^b and at least one of R ^c and R ^d are branched alkyl groups. Furthermore, z is preferably 1 or more and 10 or less. x and y are each preferably 1 or more and 500 or less.

  Surfinol 400 series (made by Shin-Etsu Chemical Co., Ltd.) is mentioned as a commercial item of the compound shown by general formula (D1) or (D2).

  The surfactants having the structures (A) to (D) described above may be used singly or in combination of two or more. In the case of using a mixture of a plurality of types, a surfactant having a structure different from the surfactant having the structure of (A) to (D) may be used in combination as long as the effect is not impaired.

Examples of the surfactant that can be used in combination include the following surfactants having a fluorine atom and surfactants having a silicone structure.
That is, as the surfactant having a fluorine atom that can be used in combination with the surfactant having the structure of (A) to (D), perfluoroalkylsulfonic acid (for example, perfluorobutanesulfonic acid, perfluorooctanesulfonic acid, etc.) ), Perfluoroalkyl carboxylic acids (for example, perfluorobutane carboxylic acid, perfluoro octane carboxylic acid, etc.), and perfluoroalkyl group-containing phosphate esters. Perfluoroalkylsulfonic acids and perfluoroalkylcarboxylic acids may be salts thereof and amide-modified products thereof.
Examples of commercially available perfluoroalkyl sulfonic acids include Megafac F-114 (manufactured by Dainippon Ink & Chemicals, Inc.), F-top EF-101, EF102, EF-103, EF-104, EF-105, and EF. -112, EF-121, EF-122A, EF-122B, EF-122C, EF-123A (JEMCO) As mentioned above, the Neos company) etc. are mentioned.
Examples of commercially available perfluoroalkylcarboxylic acids include Megafac F-410 (Dainippon Ink Chemical Co., Ltd.), F-Top EF-201, EF-204 (above, JEMCO).
As commercial products of perfluoroalkyl group-containing phosphates, MegaFac F-493, F-494 (above, manufactured by Dainippon Ink & Chemicals, Inc.) F-top EF-123A, EF-123B, EF-125M, EF -132 (above, manufactured by JEMCO).

  In addition, the surfactant having a fluorine atom that can be used in combination with the surfactant having the structure of (A) to (D) is not limited to the above, and for example, a fluorine atom-containing betaine structure compound (for example, Factent 400SW, Neos) and surfactants having amphoteric ion groups (for example, Footent SW (manufactured by Neos)) are also preferably used.

  Examples of the surfactant having a silicone structure that can be used in combination with the surfactant having the structure of (A) to (D) include general silicone oils such as dimethyl silicone, methylphenyl silicone, diphenyl silicone, and derivatives thereof. Can be mentioned.

The content of the surfactant is desirably 0.01% by mass or more and 1% by mass or less, more desirably 0.02% by mass or more and 0.000% by mass or more with respect to the charge transporting composition (total solid content excluding the solvent). 5% by mass or less. When the content of the surfactant is less than 0.01% by mass, the coating film defect preventing effect tends to be insufficient. Further, when the content of the surfactant exceeds 1% by mass, the strength of the cured film obtained by separation of the surfactant and the curing component (a compound represented by the general formula (I), other monomers, oligomers, etc.) is obtained. Tend to decrease.
Further, the surfactant having the structure of (A) to (D) is preferably contained in an amount of 1% by mass or more, more preferably 10% by mass or more.

In addition, the charge transporting composition used for forming the protective layer includes a radical having no charge transporting ability for the purpose of controlling viscosity, film strength, flexibility, smoothness, cleaning property, etc. of the composition. Polymerizable monomers, oligomers and the like may be added.
Examples of the monofunctional radical polymerizable monomer include isobutyl acrylate, t-butyl acrylate, isooctyl acrylate, lauryl acrylate, stearyl acrylate, isobornyl acrylate, cyclohexyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate 2-ethoxyethyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate, ethyl carbitol acrylate, phenoxyethyl acrylate, 2-hydroxy acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, methoxypolyethylene glycol acrylate, methoxypolyethylene glycol methacrylate , Phenoxypolyethyleneglycol Lumpur acrylate, phenoxy polyethylene glycol methacrylate, hydroxyethyl o- phenylphenol acrylate, and the like o- phenylphenol glycidyl ether acrylate.

  Examples of the bifunctional radical polymerizable monomer include 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, 2-n-butyl-2-ethyl- 1,3-propanediol diacrylate, tripropylene glycol diacrylate, tetraethylene glycol diacrylate, dioxane glycol diacrylate, polytetramethylene glycol diacrylate, ethoxylated bisphenol A diacrylate, ethoxylated bisphenol A dimethacrylate, tricyclodecane Examples include methanol diacrylate and tricyclodecane methanol dimethacrylate.

  Examples of the tri- or more functional radical polymerizable monomer include trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol acrylate, trimethylolpropane EO-added triacrylate, glycerin PO-added triacrylate, and trisacryloyloxyethylphosphine. Fate, pentaerythritol tetraacrylate, ethoxylated isocyanuric triacrylate.

  Moreover, as a radically polymerizable oligomer, an epoxy acrylate type, a urethane acrylate type, and a polyester acrylate type oligomer are mentioned, for example.

  The radically polymerizable monomer or oligomer having no charge transporting ability is desirably contained in an amount of 0 to 50% by mass, and 0 to 40% by mass with respect to the charge transporting composition (total solid content excluding solvent). % Or less is more preferable, and 0 to 30% by mass is more preferable.

In addition, it is desirable to add a thermal radical generator or a derivative thereof to the charge transporting composition used for forming the protective layer. That is, it is desirable that the protective layer contains a thermal radical generator or a derivative thereof.
Here, the “derivative of a thermal radical generator” means a reaction residue after a radical is generated by heat, or a radical active species bonded to a polymerization terminal.

Here, the cured film (crosslinked film) constituting the protective layer can be obtained by curing the charge transporting composition containing each of the above components by various methods such as heat, light, and electron beam. In order to balance the properties such as the electrical properties and mechanical strength, thermosetting is desirable. Usually, when curing a general acrylic paint or the like, an electron beam that can be cured without a catalyst and photopolymerization that can be cured in a short time are preferably used. However, in the electrophotographic photosensitive member, since the photosensitive layer which is the surface of the outermost layer contains a photosensitive material, it is difficult to damage the photosensitive material, and in order to improve the surface properties of the obtained cured film, It is desirable to perform thermosetting that allows the reaction to proceed.
Therefore, although thermosetting may be performed without a catalyst, it is desirable to use the thermal radical generator or a derivative thereof as a catalyst. Thereby, it becomes easy to suppress generation | occurrence | production of the ghost by repeated use.
The thermal radical generator or derivative thereof is not particularly limited, but a 10-hour half-life temperature of 40 ° C. or higher and 110 ° C. or lower is desirable in order to suppress damage to the photosensitive material in the photosensitive layer during the formation of the protective layer.

Commercially available products of thermal radical generators include V-30 (10-hour half-life temperature: 104 ° C.), V-40 (same: 88 ° C.), V-59 (same: 67 ° C.), V-601 (same as above: 66 ° C), V-65 (same: 51 ° C), V-70 (same: 30 ° C), VF-096 (same: 96 ° C), Vam-110 (same: 111 ° C), Vam-111 (same: 111 ° C), VE-073 (same as above: 73 ° C) (manufactured by Wako Pure Chemical Industries, Ltd.), OT _AZO- 15 (same as 61 ° C), OT _AZO- 30 (same as 57 ° C), AIBN (same as 65) ° C), AMBN (same: 67 ° C), ADVN (same: 52 ° C), ACVA (same: 68 ° C) (above, manufactured by Otsuka Chemical Co., Ltd.);
Pertetra A, Perhexa HC, Perhexa C, Perhexa V, Perhexa 22, Perhexa MC, Perbutyl H, Park Mill H, Park Mill P, Permenta H, Per Octa H, Perbutyl C, Perbutyl D, Perhexyl D, Parroyl IB, Parroyl 355, Parroyl L , Parroyl SA, Niper BW, Niper BMT-K40 / M, Parroyl IPP, Parroyl NPP, Parroyl TCP, Parroyl OPP, Parroyl SBP, Parkmill ND, Perocta ND, Perhexyl ND, Perbutyl ND, Perbutyl NHP, Perhexyl PV, Perbutyl PV, Perhexa 250, Perocta O, Perhexyl O, Perbutyl O, Perbutyl L, Perbutyl 355, Perhexyl I, Perbutyl I, Perbutyl E, Perhexa 5Z, perbutyl A, perhexyl Z, perbutyl ZT, perbutyl Z (manufactured by NOF Chemical Co., Ltd.), Kayaketal AM-C55, Trigonox 36-C75, Laurox, Parkardox L-W75, Percadox CH-50L, Trigonox TMBH, Kayakumen H, Kayabutyl H-70, Percadox BC-FF, Kaya Hexa AD, Parka Dox 14, Kaya Butyl C, Kaya Butyl D, Kaya Hexa YD-E85, Perkadox 12-XL25, Perkadox 12-EB20, Trigonox 22-N70, Trigonox 22-70E, Trigonox DT50, Trigonox 423-C70, Kayaester CND-C70, Kayaester CND-W50, Trigonox 23-C70, Trigonox 23-W5 N, Trigonox 257-C70, Kayaester P-70, Kayaester TMPO-70, Trigonox 121, Kayaester O, Kayaester HTP-65W, Kayaester AN, Trigonox42, Trigonox F-C50, Kayabutyl B, Kayacarboxyl EH- C70, Kaya-Carbon EH-W60, Kaya-Carbon I-20, Kaya-Carbon BIC-75, Trigonox 117, Kayalen 6-70 (manufactured by Kayaku Akzo), Luperox LP (same: 64 ° C.), Ruperox 610 (same: 37 ° C. ), Lupelox 188 (same: 38 ° C), Lupelox 844 (same: 44 ° C), Lupelox 259 (same: 46 ° C), Lupelox 10 (same: 48 ° C), Lupelox 701 (same: 53 ° C), Lupelox 11 ( Same: 58 ℃) Rox 26 (same: 77 ° C), Lupelox 80 (same: 82 ° C), Lupelox 7 (same: 102 ° C), Lupelox 270 (same: 102 ° C), Lupelox P (same: 104 ° C), Lupelox 546 (same: 46 ° C), Lupelox 554 (same: 55 ° C), Lupelox 575 (same: 75 ° C), Lupelox TANPO (same: 96 ° C), Lupelox 555 (same: 100 ° C), Lupelox 570 (same: 96 ° C), Lupelox TAP (same as above: 100 ° C.), Luperox TBIC (same as above: 99 ° C.), Luperlocks TBEC (same as above: 100 ° C.), Luperlocks JW (same as above: 100 ° C.), Lupelox TAIC (same as above: 96 ° C.), Lupelox TAEC (same as 99) ° C), Luperox DC (same as 117 ° C), Luperox 101 (same as 120 ° C) Lupelox F (same as 116 ° C), Lupelox DI (same as 129 ° C), Lupelox 130 (same as 131 ° C), Lupelox 220 (same as 107 ° C), Lupelox 230 (same as 109 ° C), Lupelox 233 (same as above) : 114 ° C.), Ruperox 531 (same as 93 ° C.) (above, manufactured by Arkema Yoshitomi).

  The thermal radical generator or derivative thereof is 0.001% by mass or more and 10% by mass or less based on the reactive compound (the compound represented by the general formula (I) + the other reactive compound) in the charge transporting composition. It is desirable to contain, more desirably 0.01% by mass to 5% by mass, and still more desirably 0.1% by mass to 3% by mass.

  In addition, the charge transporting composition used for forming the protective layer is added with a phenolic resin for the purpose of effectively suppressing oxidation by the discharge product gas by adding it so as not to adsorb the discharge product gas too much. You may add other thermosetting resins, such as a melamine resin and a benzoguanamine resin.

In addition, the charge transporting composition used for forming the protective layer further includes a coupling agent and a hard coating agent for the purpose of adjusting the film formability, flexibility, lubricity, and adhesiveness of the film. A fluorine-containing compound may be added. Specifically, various silane coupling agents and commercially available silicone hard coat agents are used as these additives.
As the silane coupling agent, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, tetramethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane and the like are used.
Commercially available hard coat agents include KP-85, X-40-9740, X-8239 (manufactured by Shin-Etsu Silicone), AY42-440, AY42-441, AY49-208 (manufactured by Toray Dow Corning). Etc.) are used.
Further, (tridecafluoro-1,1,2,2-tetrahydrooctyl) triethoxysilane, (3,3,3-trifluoropropyl) trimethoxysilane, 3- (hepta) for imparting water repellency and the like. Fluoroisopropoxy) propyltriethoxysilane, 1H, 1H, 2H, 2H-perfluoroalkyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorooctyl Fluorine-containing compounds such as triethoxysilane may be added.
Although the silane coupling agent is used in an arbitrary amount, the amount of the fluorine-containing compound is desirably 0.25 times or less by mass with respect to the compound not containing fluorine. If this amount is exceeded, there may be a problem with the film formability of the crosslinked film.

In addition, the charge transport composition used to form the protective layer includes discharge gas resistance, mechanical strength, scratch resistance, torque reduction, wear amount control, extended pot life, particle dispersibility, viscosity, etc. For the purpose of control, a thermoplastic resin may be added.
Polyvinyl butyral resin, polyvinyl formal resin, polyvinyl acetal resin such as partially acetalized polyvinyl acetal resin in which a part of butyral is modified with formal, acetoacetal, or the like (for example, Sleksui Chemical Co., Ltd., ESREC B, K, etc.), polyamide resin, cellulosic -Resin, polyvinyl phenol resin and the like. In particular, polyvinyl acetal resin and polyvinyl phenol resin are desirable in terms of electrical characteristics. The resin preferably has a weight average molecular weight of 2,000 to 100,000, and more preferably 5,000 to 50,000. If the molecular weight of the resin is less than 2,000, the effect due to the addition of the resin tends to be insufficient, and if it exceeds 100,000, the solubility is reduced and the addition amount is limited. It tends to cause defects. The amount of the resin added is preferably 1% by mass or more and 40% by mass or less, more preferably 1% by mass or more and 30% by mass or less, and further preferably 5% by mass or more and 20% by mass or less. If the addition amount of the resin is less than 1% by mass, the effect of the addition of the resin tends to be insufficient. If the addition amount exceeds 40% by mass, the temperature is high under high humidity (for example, 28 ° C., 85% RH). Image blur is likely to occur.

It is desirable to add an antioxidant to the charge transporting composition used for forming the protective layer for the purpose of preventing deterioration due to an oxidizing gas such as ozone generated in the charging device of the protective layer. When the mechanical strength of the surface of the photoconductor is increased and the photoconductor has a long life, the photoconductor is in contact with the oxidizing gas for a long time, and therefore, stronger oxidation resistance is required than before.
Antioxidants are preferably hindered phenols or hindered amines, organic sulfur antioxidants, phosphite antioxidants, dithiocarbamate antioxidants, thiourea antioxidants, benzimidazole antioxidants. , Etc., may be used. The addition amount of the antioxidant is preferably 20% by mass or less, and more preferably 10% by mass or less.
Examples of the hindered phenol antioxidant include 2,6-di-t-butyl-4-methylphenol, 2,5-di-t-butylhydroquinone, N, N′-hexamethylene bis (3,5-di). -T-butyl-4-hydroxyhydrocinnamide, 3,5-di-t-butyl-4-hydroxy-benzylphosphonate-diethyl ester, 2,4-bis [(octylthio) methyl] -o-cresol, 2,6-di-t-butyl-4-ethylphenol, 2,2'-methylenebis (4-methyl-6-t-butylphenol), 2,2'-methylenebis (4-ethyl-6-t-butylphenol) 4,4'-butylidenebis (3-methyl-6-t-butylphenol), 2,5-di-t-amylhydroquinone, 2-t-butyl-6- (3-butyl-2-hydro Xyl-5-methylbenzyl) -4-methylphenyl acrylate, 4,4′-butylidenebis (3-methyl-6-tert-butylphenol), and the like.

Furthermore, various particles may be added to the charge transporting composition used for forming the protective layer for the purpose of lowering the residual potential of the protective layer or improving the strength.
An example of the particles is silicon-containing particles. The silicon-containing particles are particles containing silicon as a constituent element, and specific examples include colloidal silica and silicone particles. The colloidal silica used as the silicon-containing particles is obtained by dispersing silica having an average particle diameter of 1 nm or more and 100 nm or less, preferably 10 nm or more and 30 nm or less in an organic solvent such as an acidic or alkaline aqueous dispersion, alcohol, ketone, or ester. A commercially available product may be used. The solid content of the colloidal silica in the protective layer is not particularly limited, but from the viewpoint of film forming properties, electrical properties, and strength, the charge transporting composition (total solid content mass excluding solvent) And 0.1 mass% or more and 50 mass% or less, desirably 0.1 mass% or more and 30 mass% or less.
The silicone particles used as the silicon-containing particles are selected from silicone resin particles, silicone rubber particles, and silicone surface-treated silica particles, and those commercially available are generally used. These silicone particles are spherical, and the average particle size is desirably 1 nm or more and 500 nm or less, and more desirably 10 nm or more and 100 nm or less. Silicone particles are small particles that are chemically inert and excellent in dispersibility in resin, and since the content required to obtain more sufficient properties is low, the electron does not hinder the crosslinking reaction. The surface properties of the photographic photoreceptor are improved. In other words, it is improved in lubricity and water repellency on the surface of the electrophotographic photosensitive member in a state of being taken in without a variation in a strong cross-linked structure, and has good wear resistance and contamination resistance adhesion over a long period of time. Maintained.
The content of the silicone particles in the protective layer is desirably 0.1% by mass or more and 30% by mass or less, more desirably 0.5% by mass with respect to the charge transporting composition (total solid content excluding the solvent). It is 10 mass% or less.

Other particles include fluorine-based particles such as ethylene tetrafluoride, ethylene trifluoride, propylene hexafluoride, vinyl fluoride, vinylidene fluoride, and “8th Polymer Material Forum Lecture Proceedings p89”. As shown, particles made of a resin obtained by copolymerizing a fluororesin and a monomer having a hydroxyl group, ZnO—Al ₂ O ₃ , SnO ₂ —Sb ₂ O ₃ , In ₂ O ₃ —SnO ₂ , ZnO ₂ —TiO ₂ , ZnO Examples thereof include semiconductive metal oxides such as —TiO ₂ , MgO—Al ₂ O ₃ , FeO—TiO ₂ , TiO ₂ , SnO ₂ , In ₂ O ₃ , ZnO, and MgO. For the same purpose, an oil such as silicone oil may be added. Silicone oils include silicone oils such as dimethylpolysiloxane, diphenylpolysiloxane, and phenylmethylsiloxane; amino-modified polysiloxane, epoxy-modified polysiloxane, carboxyl-modified polysiloxane, carbinol-modified polysiloxane, methacryl-modified polysiloxane, mercapto-modified poly Reactive silicone oils such as siloxane and phenol-modified polysiloxane; cyclic dimethylcyclosiloxanes such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane and dodecamethylcyclohexasiloxane; 1,3,5- Trimethyl-1.3.5-triphenylcyclotrisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetraphenylcyclo Cyclic methylphenylcyclosiloxanes such as trasiloxane, 1,3,5,7,9-pentamethyl-1,3,5,7,9-pentaphenylcyclopentasiloxane; cyclic phenylcyclosiloxanes such as hexaphenylcyclotrisiloxane Fluorine-containing cyclosiloxanes such as (3,3,3-trifluoropropyl) methylcyclotrisiloxane; hydrosilyl group-containing cyclosiloxanes such as methylhydrosiloxane mixtures, pentamethylcyclopentasiloxane, and phenylhydrocyclosiloxane; penta And vinyl group-containing cyclosiloxanes such as vinylpentamethylcyclopentasiloxane.

  In addition, a metal, a metal oxide, carbon black, or the like may be added to the charge transporting composition used for forming the protective layer. Examples of the metal include aluminum, zinc, copper, chromium, nickel, silver, and stainless steel, or those obtained by depositing these metals on the surface of plastic particles. Examples of the metal oxide include zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, tin-doped indium oxide, antimony and tantalum-doped tin oxide, and antimony-doped zirconium oxide. . These may be used alone or in combination of two or more. When two or more types are used in combination, they may be simply mixed, or may be in the form of a solid solution or fusion. The average particle diameter of the conductive particles is preferably 0.3 μm or less, particularly preferably 0.1 μm or less, from the viewpoint of transparency of the protective layer.

The charge transporting composition used for forming the protective layer is preferably prepared as a protective layer-forming coating solution, and this protective layer-forming coating solution may be solvent-free or as necessary. And alcohols such as methanol, ethanol, propanol, butanol, cyclopentanol and cyclohexanol; ketones such as acetone and methyl ethyl ketone; and solvents such as ethers such as tetrahydrofuran, diethyl ether and dioxane.
Such solvents can be used singly or in combination of two or more, but preferably have a boiling point of 100 degrees or less. As the solvent, it is particularly desirable to use a solvent having at least one hydroxyl group (for example, alcohols).

A coating solution for forming a protective layer made of a charge transporting composition used for forming a protective layer is formed by applying a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method on the charge transport layer. The film is obtained by application by a normal method such as an air knife application method, a curtain application method, or the like, and, if necessary, polymerization (curing) by heating at a temperature of 100 ° C. or more and 170 ° C. or less. As a result, a protective layer made of this film is obtained.
The oxygen concentration during the polymerization (curing) of the coating liquid for forming the protective layer is desirably 1% or less, more desirably 1000 ppm or less, and even more desirably 500 ppm or less.

  The example of the function separation type has been described as the electrophotographic photosensitive member, but the content of the charge generation material in the single-layer type photosensitive layer 6 (charge generation / charge transport layer) shown in FIG. 2 is 10% by mass or more. It is about 85% by mass or less, desirably 20% by mass or more and 50% by mass or less. The content of the charge transporting material is preferably 5% by mass or more and 50% by mass or less. The method for forming the single-layer type photosensitive layer 6 (charge generation / charge transport layer) is the same as the method for forming the charge generation layer and the charge transport layer. Single-layer type photosensitive layer (The film thickness of the charge generation / charge transport layer 6 is preferably about 5 μm to 50 μm, and more preferably 10 μm to 40 μm.

Further, in the present embodiment, the embodiment in which the outermost surface layer made of the above-described charge transporting layer is a protective layer has been described. However, in the case of a layer configuration without a protective layer, the charge located on the outermost surface in the layer configuration. The transport layer may be the outermost surface layer, and a charge transport layer may be applied to the layer.
Moreover, even if there is a protective layer, the charge transporting layer described above may be applied as the charge transporting layer below it.

[Image forming apparatus / process cartridge]
FIG. 4 is a schematic configuration diagram illustrating the image forming apparatus 100 according to the embodiment.
An image forming apparatus 100 shown in FIG. 4 includes a process cartridge 300 including an electrophotographic photosensitive member 7, an exposure device (electrostatic latent image forming unit) 9, a transfer device (transfer unit) 40, and an intermediate transfer member 50. . In the image forming apparatus 100, the exposure device 9 is disposed at a position where the electrophotographic photosensitive member 7 can be exposed from the opening of the process cartridge 300, and the transfer device 40 is interposed between the electrophotographic photosensitive member via the intermediate transfer member 50. 7, and a part of the intermediate transfer member 50 is disposed in contact with the electrophotographic photosensitive member 7.
Here, as the electrophotographic photosensitive member 7, the above-described electrophotographic photosensitive member according to the present embodiment is used. As described above, since the electrophotographic photosensitive member according to the present embodiment suppresses deterioration of electrical characteristics even when used repeatedly for a long period of time, the process cartridge and the image forming apparatus provided with this electrophotographic photosensitive member are It is possible to provide a stable image over a long period of time.

A process cartridge 300 in FIG. 4 integrally supports an electrophotographic photosensitive member 7, a charging device (charging means) 8, a developing device (developing means) 11, and a cleaning device 13 in a housing. The cleaning device 13 has a cleaning blade (cleaning member), and the cleaning blade 131 is disposed so as to contact the surface of the electrophotographic photosensitive member 7.
The process cartridge 300 is not particularly limited as long as the process cartridge 300 includes the electrophotographic photosensitive member 7 and can be attached to and detached from the image forming apparatus. If necessary, a device other than the electrophotographic photosensitive member 7 (for example, a charging device ( The charging unit 8, the developing device (developing unit) 11, and the cleaning device 13 may be integrally supported together with the electrophotographic photosensitive member 7.

  In FIG. 4, the cleaning device 13 includes a fibrous member 132 (roll shape) for supplying the lubricant 14 to the surface of the photoreceptor 7, and a fibrous member 133 (flat brush shape) that assists cleaning. Although the example used is shown, these are used as needed.

  As the charging device 8, for example, a contact type charger using a conductive or semiconductive charging roller, a charging brush, a charging film, a charging rubber blade, a charging tube or the like is used. Further, a non-contact type roller charger, a known charger such as a scorotron charger using a corona discharge or a corotron charger may be used.

  Although not shown, a photosensitive member heating member for increasing the temperature of the electrophotographic photosensitive member 7 and reducing the relative temperature is provided around the electrophotographic photosensitive member 7 for the purpose of improving the stability of the image. Also good.

  Examples of the exposure apparatus 9 include optical system devices that expose the surface of the photoconductor 7 with light such as semiconductor laser light, LED light, and liquid crystal shutter light in a desired image-like manner. The wavelength of the light source is in the spectral sensitivity region of the photoreceptor. As the wavelength of the semiconductor laser, near infrared having an oscillation wavelength near 780 nm is the mainstream. However, the present invention is not limited to this wavelength, and an oscillation wavelength laser in the 600 nm range or a laser having an oscillation wavelength in the vicinity of 400 nm to 450 nm as a blue laser may be used. For color image formation, a surface-emitting laser light source capable of multi-beam output is also effective.

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

  As the transfer device 40, for example, a contact transfer charger using a belt, a roller, a film, a rubber blade, etc., or a known transfer charger such as a scorotron transfer charger using a corona discharge or a corotron transfer charger. Can be mentioned.

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

  In addition to the above-described devices, the image forming apparatus 100 may include, for example, a light neutralizing device that performs light neutralization on the photoconductor 7.

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

  The image forming apparatus according to the present embodiment is not limited to the above configuration, and other well-known image forming apparatuses may be applied.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto. In this example, “Examples 10 to 12” are replaced with “Reference Examples 10 to 12”.

[Synthesis Example 1: Synthesis of CTM-39]
The exemplary compound CTM-39 was synthesized according to the following scheme.

In a three-necked flask, 25 g of the compound (1), 250 ml of toluene, and 12.8 g of Ethyl Maronate were collected and dissolved. Thereafter, 3.4 g of piperidine and 3.6 g of acetic acid were added and stirred at 130 ° C. for 2 hours. Further, 0.68 g of piperidine and 0.72 g of acetic acid were added and stirred at 130 ° C. for 1 hour. Thereafter, the mixture was cooled to room temperature, 250 ml of toluene was added, the organic layer was washed 3 times with 250 ml of distilled water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 10/1) to obtain 33.3 g of the oily compound (2).
Subsequently, 33.3 g of the oily compound (2) is taken into an eggplant-shaped flask, dissolved in 200 ml of tetrahydrofuran (THF), added with 50 ml of ethanol and 2 g of 10% Pd / C, and connected to a hydrogen gas supply source for 24 hours. Stir and distill off the solvent under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 20/1) to obtain 32.3 g of the oily compound (3).

Then, 25 g of the oily compound (3) was taken into an eggplant-shaped flask, dissolved in 200 ml of THF and 50 ml of ethanol, and 8.7 g of sodium hydroxide dissolved in 25 ml of distilled water was gradually added at 0 ° C. The solution was added dropwise and stirred at room temperature for 2 hours. The precipitated solid was washed twice with 100 ml of toluene. Thereafter, the solid, 200 ml of DMF, and 40 g of chloromethylstyrene were stirred at room temperature for 15 minutes and at 70 ° C. for 7 hours. Thereafter, the mixture was cooled to room temperature, 500 ml of toluene was added, the organic layer was washed three times with 500 ml of distilled water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 20/1) to obtain 27.1 g of oily compound CTM-39.
The structure of CTM-39 obtained was identified by the IR spectrum.
IR spectrum data of CTM-39 is shown in FIG.

[Synthesis Example 2: Synthesis of CTM-40]
The exemplary compound CTM-40 was synthesized according to the following scheme.

25 g of the above compound (3) synthesized by the same method as in Synthesis Example 1 was dissolved in 250 ml of THF, 8.9 g of lithium aluminum hydride was added, and the mixture was stirred at room temperature for 2 hours. Thereafter, 500 ml of water and 1 L of toluene were added, and the solid content was separated by filter paper with celite. Further, the organic layer was washed with 500 ml of distilled water three times, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, recrystallization from 20 ml of hexane and 30 ml of ethyl acetate gave 18.5 g of the above compound (4) as a pale pink solid.
Subsequently, 16.5 g of the solid compound (4) was dissolved in 200 ml of THF, 18 g of 4-chloromethylstyrene and 11.9 g of potassium tert-butoxide were gradually added, and the mixture was stirred at 70 ° C. for 16 hours. Thereafter, the mixture was cooled to room temperature, 250 ml of toluene was added, the organic layer was washed 3 times with 250 ml of distilled water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 20/1) to obtain 20.3 g of oily CTM-40.
The resulting CTM-40 was identified for structure by IR spectrum.
IR spectrum data of CTM-40 is shown in FIG.

[Synthesis Example 3: Synthesis of CTM-44]
The exemplary compound CTM-44 was synthesized according to the following scheme.

In a three-necked flask, 25 g of the above compound (5), 250 ml of toluene, and 12.8 g of Ethyl Maronate were collected and dissolved. Thereafter, 3.4 g of piperidine and 3.6 g of acetic acid were added and stirred at 130 ° C. for 2 hours. Further, 0.68 g of piperidine and 0.72 g of acetic acid were added and stirred at 130 ° C. for 1 hour. Thereafter, the mixture was cooled to room temperature, 250 ml of toluene was added, the organic layer was washed 3 times with 250 ml of distilled water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 20/1) to obtain 31.2 g of the oily compound (6).
Subsequently, 31.2 g of the above oily compound (6) is taken into an eggplant-shaped flask, dissolved in 200 ml of THF, added with 50 ml of ethanol and 2 g of 10% Pd / C, connected to a hydrogen gas supply source and stirred for 24 hours, The solvent was distilled off. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 20/1) to obtain 29.8 g of the oily compound (7).

Then, 25 g of the oily compound (7) was taken into an eggplant-shaped flask, dissolved in 200 ml of THF and 50 ml of ethanol, and 8.7 g of sodium hydroxide dissolved in 25 ml of distilled water was gradually added dropwise at 0 ° C. And stirred at room temperature for 2 hours. The precipitated solid was washed twice with 100 ml of toluene. Thereafter, the solid, 200 ml of DMF, and 40 g of chloromethylstyrene were stirred at room temperature for 15 minutes and at 70 ° C. for 7 hours. Thereafter, the mixture was cooled to room temperature, 500 ml of toluene was added, the organic layer was washed three times with 500 ml of distilled water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 20/1) to obtain 25.3 g of oily compound CTM-44.
The resulting CTM-44 was identified by IR spectrum.
IR spectrum data of CTM-44 is shown in FIG.

[Synthesis Example 4: Synthesis of CTM-45]
The exemplary compound CTM-45 was synthesized according to the following scheme.

25 g of the above compound (7) synthesized in the same manner as in Synthesis Example 3 was dissolved in 250 ml of THF, 9.2 g of lithium aluminum hydride was added, and the mixture was stirred at room temperature for 2 hours. Thereafter, 500 ml of water and 1 L of toluene were added, and the solid content was separated by filter paper with celite. Further, the organic layer was washed with 500 ml of distilled water three times, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 2/1) to obtain 17.8 g of the oily compound (8).
Subsequently, 16.0 g of the oily compound (8) was dissolved in 200 ml of THF, 17.5 g of 4-chloromethylstyrene and 11.2 g of potassium tert-butoxide were gradually added, and the mixture was stirred at 70 ° C. for 16 hours. Thereafter, the mixture was cooled to room temperature, 250 ml of toluene was added, the organic layer was washed 3 times with 250 ml of distilled water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 20/1) to obtain 18.7 g of oily CTM-45.
The resulting CTM-45 was identified by IR spectrum.
IR spectrum data of CTM-45 is shown in FIG.

[Synthesis Example 5: Synthesis of CTM-46]
The exemplified compound CTM-46 was synthesized according to the following scheme.

In the same manner as in Synthesis Example 3, the compound (6) was synthesized from the compound (5).
27.5 g of the above oily compound (6) is taken into an eggplant-shaped flask, dissolved in 200 ml of THF and 50 ml of ethanol, and 8.7 g of sodium hydroxide dissolved in 25 ml of distilled water is gradually added dropwise at 0 ° C. And stirred at room temperature for 2 hours. The lower layer separated into two layers was washed twice with 100 ml of toluene. Thereafter, the lower layer, 200 ml of DMF and 40 g of chloromethylstyrene were stirred at room temperature for 15 minutes and at 70 ° C. for 7 hours. Thereafter, the mixture was cooled to room temperature, 500 ml of ethyl acetate was added, the organic layer was washed 3 times with 500 ml of distilled water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 20/1) to obtain 18.4 g of oily compound CTM-46.
The resulting CTM-46 was identified by IR spectrum.
IR spectrum data of CTM-46 is shown in FIG.

[Synthesis Example 6: Synthesis of CTM-71]
The exemplary compound CTM-71 was synthesized according to the following scheme.

In a three-necked flask, 25 g of the above compound (9), 350 ml of toluene, and 22.1 g of Ethyl Maronate were collected. Thereafter, 1.56 g of piperidine and 1.65 g of acetic acid were added, and the mixture was stirred at 130 ° C. for 2.5 hours. Further, 0.78 g of piperidine and 0.83 g of acetic acid were added and stirred at 130 ° C. for 1 hour. Thereafter, the mixture was cooled to room temperature, 500 ml of toluene was added, the organic layer was washed three times with 500 ml of distilled water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 10/1) to obtain 28.5 g of the oily compound (10).
Subsequently, 28.5 g of the oily compound (10) is taken into an eggplant-shaped flask, dissolved in 200 ml of THF, added with 25 ml of ethanol and 2 g of 10% Pd / C, connected to a hydrogen gas supply source, stirred for 24 hours, The lower solvent was distilled off. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 20/1) to obtain 27.1 g of the oily compound (11).
Then, 27.1 g of compound (11) was dissolved in 250 ml of THF, 6.2 g of lithium aluminum hydride was added, and the mixture was stirred at room temperature for 2 hours. Thereafter, 500 ml of water and 1 L of ethyl acetate were added, and the solid content was separated by filtration through celite. Further, the organic layer was washed with 500 ml of distilled water three times, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, it was purified by ram chromatography (adsorbent: silica gel, solvent: ethyl acetate) to obtain 19.1 g of the oily compound (12).
Subsequently, 19.1 g of the above compound (12) was dissolved in 200 ml of THF, 23.7 g of 4-chloromethylstyrene, 17.4 g of potassium tert-butoxide were gradually added, and the mixture was stirred at 70 ° C. for 16 hours. Thereafter, the mixture was cooled to room temperature, 250 ml of toluene was added, the organic layer was washed 3 times with 250 ml of distilled water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Thereafter, the residue was purified by column chromatography (adsorbent: silica gel, solvent: toluene / ethyl acetate = 20/1) to obtain 20.3 g of oily CTM-71.

The resulting CTM-71 was identified by IR spectrum.
IR spectrum data of CTM-71 is shown in FIG.

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

Zinc oxide provided with this alizarin: 60 parts by mass, curing agent (blocked isocyanate Sumijoule 3175, manufactured by Sumitomo Bayern Urethane Co., Ltd.): 13.5 parts by mass, butyral resin (ESREC BM-1, manufactured by Sekisui Chemical Co., Ltd.) ): 15 parts by mass of 38 parts by mass of methyl ethyl ketone mixed with 85 parts by mass of methyl ethyl ketone: 25 parts by mass of methyl ethyl ketone were mixed, and dispersion was performed for 2 hours with a sand mill using glass beads having a diameter of 1 mmφ. Got.
Dioctyltin dilaurate: 0.005 parts by mass and silicone resin particles (Tospearl 145, manufactured by GE Toshiba Silicone): 40 parts by mass were added as catalysts to the obtained dispersion to obtain a coating liquid for forming an undercoat layer. . This coating solution was applied on an aluminum substrate by a dip coating method, followed by drying and curing at 175 ° C. for 40 minutes to obtain an undercoat layer having a thickness of 22 μm.

-Fabrication of charge generation layer-
Bragg angles (2θ ± 0.2 °) of X-ray diffraction spectrum using Cukα characteristic X-ray as a charge generating material are at least 7.3 °, 16.0 °, 24.9 °, 28.0 ° A mixture consisting of 15 parts by mass of hydroxygallium phthalocyanine having a diffraction peak, 10 parts by mass of vinyl chloride / vinyl acetate copolymer resin (VMCH, manufactured by Nihon Unicar) as a binder resin, and 200 parts by mass of n-butyl acetate. The mixture was dispersed for 4 hours in a sand mill using glass beads having a diameter of 1 mmφ. To the obtained dispersion, 175 parts by mass of n-butyl acetate and 180 parts by mass of methyl ethyl ketone were added and stirred to obtain a coating solution for forming a charge generation layer. This charge generation layer forming coating solution was dip coated on the undercoat layer and dried at room temperature (25 ° C.) to form a charge generation layer having a thickness of 0.15 μm.

-Preparation of charge transport layer-
48 parts by mass of N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1 ′] biphenyl-4,4′-diamine (hereinafter referred to as “TPD”) and bisphenol Z 52 parts by mass of a polycarbonate resin (hereinafter referred to as “PCZ500”, viscosity average molecular weight: 50,000) was added to 800 parts by mass of chlorobenzene and dissolved to obtain a coating solution for forming a charge transport layer. This coating solution was applied onto the charge generation layer and dried at 130 ° C. for 45 minutes to form a charge transport layer having a thickness of 22 μm.

-Production of protective layer-
20 parts by mass of the compound represented by formula (I) (Exemplary Compound CTM-9) is dissolved in 15 parts by mass of stabilizer-free tetrahydrofuran (THF) and 15 parts by mass of cyclopentyl methyl ether, and further, initiator V -601 (made by Wako Pure Chemical Industries) 3.8 mass parts was dissolved, and the coating liquid for protective layer formation was obtained. This coating solution was applied onto the charge transport layer and heated at 155 ° C. for 40 minutes in an atmosphere having an oxygen concentration of about 80 ppm to form a protective layer having a thickness of 7 μm.
An electrophotographic photoreceptor was obtained by the method as described above. This photoreceptor is referred to as a photoreceptor 1.

(Evaluation)
(1) Measurement of charging potential (surface potential) and residual potential The obtained electrophotographic photosensitive member was subjected to the following steps (A) to (C) at high temperature and high humidity (28 ° C., 67% RH).
(A): Step of charging the electrophotographic photosensitive member with a scorotron charger with a grid applied voltage of −700 V (B): 10.0 erg / cm ² light using a semiconductor laser with a wavelength of 780 nm one second after step (A) Exposure step (C) for irradiating with 50.0 erg / cm ² of red LED light 3 seconds after step (A) At this time, using the laser printer remodeling scanner, the above steps were repeated 100 kcycles .

VH (surface potential of the photoconductor after being charged in step (A)), VL (surface potential of the photoconductor after exposure in step (B)), and VRP (step ( The surface potential (residual potential) of the photoconductor after being neutralized in C) was measured, and the initial VH, VL, and VRP, and the variations ΔVH, ΔVL, and ΔVRP from the initial stage were obtained.
In addition, the surface potential meter MODEL344 (made by Trek Japan) was used for the measurement of the surface potential (residual potential).

The evaluation index is as follows.
(VL evaluation index)
A: -240V or more B: -280V or more and less than -240V C: -300V or more and less than -280V D: -300V or less (VRP evaluation index)
A: -130 V or more B: -150 V or more and less than -130 V C: -170 V or more and less than -150 V D: less than -170 V (evaluation index of ΔVH, ΔVL, and ΔVRP)
A: 10 V or less B: More than 10 V and 20 V or less C: More than 20 V and 30 V or less D: More than 30 V These results are shown in Table 4.

(2) Evaluation of initial image quality: Evaluation of ghost The produced electrophotographic photosensitive member is mounted on “Docu Center-III C7600 (K color)” manufactured by Fuji Xerox Co., Ltd., in an environment of 28 ° C. and 67% RH as follows. The ghost was evaluated (test 1).
For this evaluation, Fuji Xerox P paper (A4 size, short direction feed) was used.

-Evaluation of ghost-
For the ghost, a chart of a pattern having G and a black area shown in FIG. 6A was printed, and the appearance of the letter G in the black area was visually evaluated.
A: Good or slight as shown in FIG.
B: Slightly conspicuous as shown in FIG. 6 (B) C: It is clearly confirmed as shown in FIG. 6 (C).

(3) Image quality evaluation after print test: Evaluation of ghost The produced electrophotographic photosensitive member was mounted on “Docu Center-III C7600 (K color)” manufactured by Fuji Xerox Co., Ltd., and the environment was 28 ° C. and 67% RH. % Halftone print test was performed 10,000 sheets.
Thereafter, the ghost was evaluated (test 2) in the same manner as described above in an environment of 28 ° C. and 67% RH.

(4) Initial surface observation (2) Initial image quality evaluation: The surface of the electrophotographic photosensitive member at the time of ghost evaluation was observed, and surface observation (test 1) was performed as follows.

-Surface observation-
The surface of the electrophotographic photosensitive member was observed and evaluated as follows.
A: Even if it is magnified 20 times, both scratches and adhesion are not visible.
B: Deposits are observed when magnified 20 times. C: Slight scratches are observed when magnified 20 times. D: Slight scratches or deposits are observed even with the naked eye.
E: Scratches or deposits are clearly seen even with the naked eye.

(5) Surface observation after print test (3) Image quality evaluation after print test: The surface of the electrophotographic photosensitive member at the time of ghost evaluation was observed, and surface observation (test 2) was performed in the same manner as described above.

[Examples 2 to 15, Comparative Example 1]
(Preparation of electrophotographic photoreceptor)
The layers up to the charge transport layer were prepared in the same manner as in Example 1, and the composition of the material used for forming the protective layer was changed as shown in Table 3 to obtain a coating liquid for forming a protective layer. Each coating solution was applied onto the charge transport layer and heated at 155 ° C. for 40 minutes in an atmosphere having an oxygen concentration of about 80 ppm to form a protective layer having a thickness of 7 μm.
An electrophotographic photoreceptor was obtained by the method as described above. This photoreceptor is referred to as photoreceptors 2 to 15 and comparative photoreceptor R1.
Here, Ref CT-1 used as a compound having charge transport ability in Comparative Example 1 is shown below.

(Evaluation)
The obtained photoreceptor was evaluated in the same manner as in Example 1. The results are shown in Table 4.

From the above results, it can be seen that the present example is superior in VL and VRP as compared with the comparative example, and is also excellent in the fluctuation amounts ΔVH, ΔVL, and ΔVRP from the initial stage.
Further, compared with the comparative example, the present example was excellent in ghost at the initial stage and after the print test, and a good result was obtained in the surface observation after the print test.

DESCRIPTION OF SYMBOLS 1 Undercoat layer, 2 Charge generation layer, 3 Charge transport layer, 4 Conductive substrate, 5 Protective layer, 6 Single layer type photosensitive layer, 7A, 7B, 7C, 7 Electrophotographic photoreceptor, 8 Charging device, 9 Exposure device , 11 Developing device, 13 Cleaning device, 14 Lubricant, 40 Transfer device, 50 Intermediate transfer member, 100 Image forming device, 120 Image forming device, 300 Process cartridge

Claims (6)

An electrophotographic photosensitive member provided with a charge transporting layer containing a polymer of a compound represented by the following general formula (I).


[In general formula (I), F represents a charge transporting subunit , and the following partial structure (A) in the compound represented by general formula (I) is represented by the following general formula (IV-1). Group, group represented by the following general formula (IV-2), group represented by the following general formula (V-1), or group represented by the following general formula (V-2) . m represents an integer of 1 to 6. ]

[In General Formulas (IV-1) and (IV-2), X represents a linking group, and p represents 0 or 1. In the general formulas (V-1) and (V-2), X ′ represents a linking group, and p ′ represents 0 or 1. In the partial structure (A), the wavy line indicates the binding site with the charge transporting subunit indicated by F. ] The electrophotographic photosensitive member according to claim 1, wherein the compound represented by the general formula (I) is a compound represented by the following general formula (II).

[In General Formula (II), Ar ^{1 to} Ar ⁴ each independently represent a substituted or unsubstituted aryl group, Ar ⁵ represents a substituted or unsubstituted aryl group, or a substituted or unsubstituted arylene group, and D Is a group represented by the general formula (IV-1), a group represented by the general formula (IV-2), a group represented by the general formula (V-1), or the general formula (V- The group represented by 2) is shown. k is 0 or 1, c1 to c5 represent an integer of 0 to 2, that all of c1 to c5 becomes 0 at the same time have greens. ] The electrophotographic photosensitive member according to the charge-transporting layer to claim 1 or claim 2 comprising as an outermost surface layer. The electrophotographic photoreceptor according to any one of claims 1 to 3 , wherein the charge transporting layer further contains a thermal radical generator or a derivative thereof. The electrophotographic photosensitive member according to any one of claims 1 to 4 , comprising:
A process cartridge that can be attached to and detached from an image forming apparatus. The electrophotographic photosensitive member according to any one of claims 1 to 4 ,
Charging means for charging the electrophotographic photoreceptor;
Electrostatic latent image forming means for forming an electrostatic latent image on the charged electrophotographic photosensitive member;
Developing means for developing the electrostatic latent image formed on the electrophotographic photosensitive member with toner to form a toner image;
Transfer means for transferring the toner image to a transfer object;
An image forming apparatus comprising: