JP2005126409A - Stilbene derivative, method for producing the same and electrophotographic receptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stilbene derivative having excellent compatibility with a binder resin owing to the presence of three diphenylenamine structures at prescribed parts in the molecule of a stilbene derivative and exhibiting a prescribed sensitivity from the initial stage for a long period, a method for the production of the stilbene derivative and an electrophotographic receptor containing the stilbene derivative. <P>SOLUTION: The stilbene derivative has three diphenylenamine structures and is expressed by general formula (1) (A is a trivalent organic group containing a substituted or unsubstituted aromatic ring; and R<SP>1</SP>to R<SP>7</SP>, B<SP>1</SP>and B<SP>2</SP>are each independently hydrogen atom, a halogen atom, a 1-20C substituted or unsubstituted alkyl or the like wherein the B<SP>1</SP>and B<SP>2</SP>groups may be bonded or condensed to form a substituted or unsubstituted carbon ring structure). The invention further relates to a method for the production of the stilbene derivative and an electrophotographic receptor containing the stilbene derivative. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a stilbene derivative having a predetermined sensitivity by having three enamine structures (enamine units) in the molecule, a method for producing the same, and an electrophotographic photoreceptor containing the stilbene derivative.

Conventionally, as an electrophotographic photosensitive member for an image forming apparatus or the like, an organic photosensitive member made of an organic photosensitive material such as a charge transporting agent, a charge generating agent, and a binder resin (binder resin) has been used. Such an organic photoreceptor is advantageous in that it is easy to manufacture and has a wide degree of freedom in structural design because it has various options for the photoreceptor material as compared with conventional inorganic photoreceptors.
Among such organic photoreceptor materials, as a charge transporting agent having a predetermined charge mobility, an enamine compound having one diphenylenamine structure represented by the following general formula (74) and an electrophotographic photoreceptor using the same Is known (see, for example, Patent Document 1).

(In General Formula (74), B is an arylene group, a divalent heterocyclic residue, an alkylene group, or a divalent group of an aromatic hydrocarbon linked by an alkylene chain, Ar ³ is an aryl group, (It is a heterocyclic group or an aralkyl group, Ar ⁴ is an aryl group or a heterocyclic group, and Z ¹ is an atomic group necessary for forming a ring together with Ar ⁴ and a carbon atom.)

  Similarly, an electrophotographic photoreceptor containing an enamine compound having two diphenyl enamine structures represented by the following general formula (75) as a charge transport agent is also known (see, for example, Patent Document 2).

(In the general formula (75), Ar ^{5 to} Ar ¹⁰ represent an aryl group or a heterocyclic group, Z represents an atomic group that forms a ring with Ar ⁵ and Ar ⁶ , and Ar ^{5 to} Ar ¹⁰ represent an aralkyl group or an alkyl group. Ar ⁹ and Ar ¹⁰ may form a ring together, R ²⁹ represents hydrogen or an alkyl group, and m represents an integer of 0 to 2.)
JP 2003-167364 A (Claims) JP2003-12629 (Claims)

  However, each of the enamine compounds described in Patent Document 1 and Patent Document 2 does not include a stilbene structure as a central structure, and there is a problem that charge mobility is insufficient. Further, since the compatibility with the binder resin is poor and it is difficult to uniformly disperse in the electrophotographic photosensitive member, there has been a problem that charge transfer hardly occurs during use. That is, each of the disclosed enamine compounds has not only insufficient charge mobility, but also a problem that it is difficult to produce and inferior in durability.

Therefore, the present inventors have introduced a plurality of enamine structures symmetrically at predetermined positions in the molecule in the stilbene derivative, so that the compatibility with the binder resin is excellent, and not only in the initial stage, but also in the long The fact that the sensitivity improves over time has led to the completion of the present invention.
That is, the object of the present invention is to solve the above-mentioned technical problems and to be suitably used as a charge transport agent such as an electrophotographic photosensitive member, a stilbene derivative having three enamine structures, a method for producing the same, and An object of the present invention is to provide an electrophotographic photosensitive member having a predetermined sensitivity.

  According to the present invention, a stilbene derivative having three enamine structures, which is represented by the following general formula (1), is provided, and the above-described problems can be solved.

(In General Formula (1), A is a trivalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁷ , B ¹ and B ² are each an independent hydrogen atom, Halogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, carbon number 6 -20 substituted or unsubstituted aryl group, substituted or unsubstituted amino group, substituted or unsubstituted ethenyl group having 2 to 30 carbon atoms, substituted or unsubstituted styryl group having 8 to 20 carbon atoms, or plural B ¹ and B ^{2 of the above} are a substituted or unsubstituted carbocyclic structure formed by bonding or condensation.)

  In constituting the stilbene derivative of the present invention, the trivalent organic group represented by the symbol A in the general formula (1) is preferably an organic group represented by the following general formula (2).

(In General Formula (2), R ^{8 to} R ¹⁹ are each independently an hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted halogen group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms.)

In constituting the stilbene derivative of the present invention, a plurality of R ¹ , R ² , R ⁴ , R ⁵ , R ⁶ and R ^{7 in} the general formula (1) are each an independent hydrogen atom or 1 carbon atom. It is preferably a -20 substituted or unsubstituted alkyl group.

In constituting the stilbene derivative of the present invention, a plurality of R ³ in the general formula (1) are each independently an hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or the following general formula ( It is preferable that it is a substituent represented by 3).

(In General Formula (3), R ^{20 to} R ²⁶ are each an independent hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and a substituted or unsubstituted halogen group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms.)

  Another aspect of the present invention is a method for producing a stilbene derivative having three enamine structures as shown in reaction formula (1), which comprises a formylated enamine derivative represented by general formula (4) and a formula: A stilbene derivative having three enamine structures represented by the general formula (1) is reacted with the triphosphate derivative represented by (5) in the presence of a base: Production method.

(In the reaction formula (1), A is a trivalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁷ , B ¹ and B ² are each an independent hydrogen atom, Halogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, carbon number 6 -20 substituted or unsubstituted aryl group, substituted or unsubstituted amino group, substituted or unsubstituted ethenyl group having 2 to 30 carbon atoms, substituted or unsubstituted styryl group having 8 to 20 carbon atoms, or plural B ¹ and B ² are a substituted or unsubstituted carbocyclic structure formed by bonding or condensation.

  In carrying out the method for producing a stilbene derivative of the present invention, an aniline represented by the general formula (6) as shown in the following reaction formula (2) is used as the formylated enamine derivative represented by the general formula (4). It is obtained by reacting a derivative with an acetaldehyde derivative represented by the general formula (7) to obtain a diphenyl enamine derivative represented by the general formula (8), and then formylating it by the Vilsmeier method. It is preferred to use a formylated enamine derivative.

(In the reaction formula (2), a plurality of R ^{1 to} R ⁷ , B ¹ and B ² are each an independent hydrogen atom, halogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, 20 substituted or unsubstituted alkyl halide groups, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted aryl group having 6 to 20 carbon atoms, substituted or unsubstituted amino group, carbon number A substituted or unsubstituted ethenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted styryl group having 8 to 20 carbon atoms, or a substituted or unsubstituted carbon formed by bonding or condensing a plurality of B ¹ and B ² Ring structure.)

  Another embodiment of the present invention is an electrophotographic photosensitive member having a photosensitive layer provided on a conductive substrate, wherein the photosensitive layer has three enamine structures represented by the following general formula (1). An electrophotographic photosensitive member characterized by comprising:

(In General Formula (1), A is a trivalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁷ , B ¹ and B ² are each an independent hydrogen atom, Halogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, carbon number 6 -20 substituted or unsubstituted aryl group, substituted or unsubstituted amino group, substituted or unsubstituted ethenyl group having 2 to 30 carbon atoms, substituted or unsubstituted styryl group having 8 to 20 carbon atoms, or plural B ¹ and B ^{2 of the above} are a substituted or unsubstituted carbocyclic structure formed by bonding or condensation.)

  In constituting the electrophotographic photosensitive member of the present invention, the photosensitive layer is preferably a single layer type further containing a charge generating agent and an electron transporting agent.

According to the present invention, as represented by the general formula (1), the enamine structure is present at each of three symmetrical positions in the molecule, so that the compatibility with the binder resin is excellent, and the charge transfer A stilbene derivative having a high degree and a predetermined sensitivity over a long time can be provided.
That is, the stilbene derivative having a predetermined structure represented by the general formula (1) has three molecular ends, each having an enamine structure at a symmetrical position, so that the molecular weight is relatively large. It is characterized by high compatibility with the binder resin and high charge mobility. Therefore, when used as a charge transfer agent (hole transfer agent) in an electrophotographic photosensitive member, a film having a uniform thickness can be formed, and an electrophotographic photosensitive member having a predetermined sensitivity over a long time is provided. be able to.

  Further, according to the stilbene derivative of the present invention, A in the general formula (1) has a predetermined organic group represented by the general formula (2), so that the π-conjugated system is expanded and the charge mobility is excellent. Has features. Therefore, by using it as a hole transport agent in an electrophotographic photoreceptor, an electrophotographic photoreceptor having stable sensitivity characteristics and excellent durability even when used for a long time can be provided.

Further, according to the stilbene derivative of the present invention, a plurality of R ¹ , R ² , R ⁴ , R ⁵ , R ⁶ and R ^{7 in} the general formula (1) are each independently an hydrogen atom or a carbon number of 1 to By being 20 substituted or unsubstituted alkyl groups, the production of a stilbene derivative having a predetermined structure is facilitated, and such a derivative can be obtained stably.

In addition, according to the stilbene derivative of the present invention, since a plurality of R ³ in the general formula (1) are each an alkyl group or the like, it is easy to produce a stilbene derivative having a predetermined structure. It can be obtained stably.
Moreover, when several R < ³ > is a substituent represented by General formula (3), intramolecular conjugation can be extended, As a result, when it uses as a hole transport agent in an electrophotographic photoreceptor. In addition to improving stability and durability, it is possible to exhibit excellent sensitivity for a long time.

  In addition, according to the method for producing a stilbene derivative of the present invention, a formylation enamine derivative having a predetermined structure and a triphosphate ester derivative having a predetermined structure are reacted in the presence of a base, thereby being represented by the general formula (1). The obtained stilbene derivative can be obtained efficiently.

  Further, according to the method for producing a stilbene derivative of the present invention, after obtaining an enamine derivative having a predetermined structure, formylation is performed by the Vilsmeier method, a formylated enamine derivative having a predetermined structure can be efficiently obtained. As a result, the stilbene derivative represented by the general formula (1) can be obtained more efficiently.

  In addition, according to the electrophotographic photosensitive member of the present invention, by containing the stilbene derivative having the predetermined structure represented by the general formula (1), the stilbene derivative has a large charge mobility and can maintain the predetermined sensitivity for a long time. Can be provided. That is, it is possible to efficiently obtain an electrophotographic photosensitive member having high charge mobility and low residual potential while having a predetermined sensitivity for a long time.

  In addition, according to the electrophotographic photosensitive member of the present invention, the single-layer type photosensitive member containing the stilbene derivative having the predetermined structure represented by the general formula (1) can be easily configured and manufactured. Nevertheless, an electrophotographic photosensitive member having a predetermined sensitivity for a long time can be obtained.

  Hereinafter, embodiments relating to a stilbene derivative of the present invention, a method for producing the same, and an electrophotographic photoreceptor will be specifically described with reference to the drawings as appropriate.

[First embodiment]
The first embodiment is a stilbene derivative having three enamine structures, which is represented by the following general formula (1). In addition, the contents of A, R ^{1 to} R ⁷ , B ¹ and B ^{2 in} the general formula (1) have already been defined above.

  Here, as a suitable example of the stilbene derivative represented by the general formula (1), stilbene derivatives (HTM-A to I) having three diphenylenamine structures represented by the following formulas (9) to (17) are shown. .

Moreover, as a trivalent organic group containing the substituted or unsubstituted aromatic ring represented by A in General formula (1), it is a carbocyclic structure represented by General formula (2) mentioned above. preferable.
This is because the electrical characteristics and heat resistance can be improved by being such a specific carbocyclic structure, or the electron distribution is delocalized and planarized. This is because the charge mobility can be increased and the charge injection property from the charge generating agent can be enhanced.
Therefore, when the stilbene derivative related to the electrophotographic photoreceptor is used as a hole transport agent, an electrophotographic photoreceptor having stable sensitivity characteristics can be provided even when used repeatedly for a long time. In addition, such a carbocyclic structure is relatively easy to introduce, and a stilbene derivative having a predetermined stability can be obtained in a relatively high yield.

[Second Embodiment]
The second embodiment is a method for producing a stilbene derivative having three enamine structures represented by the reaction formula (1), wherein the formylated enamine derivative represented by the general formula (4) and the general formula (5) And a triphosphate derivative represented by formula (1) in the presence of a base to obtain a stilbene derivative represented by the general formula (1). The contents of A, R ^{1 to} R ⁷ , B ¹ and B ^{2 in} the reaction formula (1) are the contents defined in the description of the general formula (1) unless otherwise specified.

1. Formylation Diphenyl Enamine Derivative Here, in describing the reaction formula (1), a method for synthesizing the formylation enamine derivative represented by the general formula (4) as a raw material will be described in detail.

(1) Reaction formula It is preferable to synthesize | combine the formylation enamine derivative represented by General formula (4) using the Filsmeier method, as shown in the following reaction formula (2).
That is, the formylated enamine derivative represented by the general formula (4) is obtained by reacting the diphenylamine compound represented by the general formula (6) with the acetaldehyde derivative represented by the general formula (7). After obtaining the enamine derivative represented, it can be obtained by formylation by the Vilsmeier method.
Incidentally, R ¹ to R ^7, B ¹ and B ² in the reaction formula (2) is a same as the contents of the reaction equation (1), the contents which have already been described above.

(2) Specific Reaction Step (2) -1 First Step In the first step, the aniline derivative represented by the general formula (6) and the acetaldehyde derivative represented by the general formula (7) are reacted, It is preferable to prepare an enamine derivative represented by the general formula (8).

Here, the addition ratio of the aniline derivative (diphenylamine compound) represented by the general formula (6) and the acetaldehyde derivative represented by the general formula (7) is 1: 0.5 to 1: 3 in molar ratio. A value within the range is preferable.
The reason for this is that when the ratio of the aniline derivative and the acetaldehyde derivative is less than 1: 0.5, the amount of diphenylenamine derivative that is the target product may be reduced. On the other hand, if the ratio of the aniline derivative and acetaldehyde exceeds 1: 3, a large amount of unreacted acetaldehyde remains, which may make it difficult to purify the target diphenyl enamine derivative. .
Therefore, the addition ratio of the aniline derivative represented by the general formula (6) and the acetaldehyde derivative represented by the general formula (7) is set to a value in the range of 1: 0.7 to 1: 2 in terms of molar ratio. It is more preferable.
Moreover, when making the aniline derivative represented by General formula (6) react with the acetaldehyde derivative represented by General formula (7), while making reaction temperature into the value within the range of 50-200 degreeC normally, The reaction temperature is preferably set to a value within the range of 1 to 30 hours.
This is because, under such reaction conditions, a desired reaction can be efficiently performed using a relatively simple manufacturing facility.

(2) -2 Second Step Next, it is preferable to prepare a formylated enamine derivative represented by the general formula (4) from the enamine derivative represented by the general formula (8) by using the Filsmeier method.

The Filsmeier reagent (Vilsmeier reagent) used in the Filsmeier method is preferably a combination of the following compounds (i) and (ii).
(i) Halogenating agents such as phosphorus oxychloride, phosgene, oxalyl chloride, thionyl chloride, triphenylphosphine-bromine, hexachlorotriphosphazatriene
(ii) N, N-dimethylformamide (DMF), N-methylformanilide (MFA), N-formylmorpholine, N, N-diisopropylformamide In the present invention, as the Filsmeier reagent, phosphorus oxychloride and a solvent A combination with DMF that can also be used as

In the preparation of the Vilsmeier reagent, the ratio of the compounds (i) and (ii) used is usually a molar ratio, preferably within a range of 1: 1 to 1:20. A value in the range of 1: 5 is more preferable.
Furthermore, it is preferable to set it as the value within the range of 0.9-2 times mole amount with respect to 1 mol of enamine compounds represented by General formula (8) regarding the usage-amount of a Vilsmeier reagent, 1-1. It is more preferable to set the value within the range of 1-fold molar amount.
In addition, regarding the reaction conditions for formylation of the enamine derivative represented by the general formula (8) in the Vilsmeier method, the reaction is usually performed at a temperature of 130 ° C. or less, and the reaction time is a value within the range of 0.5 to 5 hours. It is preferable to do.

(2) -3 Others Further, when R ³ in the general formula (4) contains an ethenyl group, as shown in the reaction formula (2 ′), R ³ which is the first hydrogen atom is converted to the Filsmeier method. Can be prepared by reacting the phosphorus ylide derivative represented by the general formula (19) by Witchig method after formylation.

(R ¹ , R ² , R ⁴ , R ⁵ , R ⁶ , R ⁷ , B ¹ and B ² in the reaction formula (2 ′) are R ¹ , R ² , R ^{4 in the} reaction formula (2). , R ⁵ , R ⁶ , R ⁷ , B ¹ and B ² , R ²⁷ and R ²⁸ are substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, or R ²⁷ and R ^28. Is a substituted or unsubstituted carbocyclic structure formed by bonding or condensation, and the repeating number m is an integer of 0 to 2.)

  Here, the method for synthesizing the ethenyl derivative represented by the general formula (8 ′) is preferably performed according to the method for synthesizing the ethenyl derivative represented by the general formula (8).

Next, a formylation enamine derivative represented by the general formula (18) is prepared by the first stage Philsmyer method.
In addition, about the reaction conditions of the 1st step | form Filsmeier method, it is preferable to carry out according to the Filsmeier method in 1st process.

  Next, an enamine derivative represented by the general formula (20) is prepared by a Wittig reaction. That is, it is made to react with the presence of formyl ethenyl derivative represented by the general formula (18), phosphorus ylide derivative represented by the formula (19) and n-BuLi as a catalyst.

Here, the addition ratio of the formylated ethenyl derivative represented by the general formula (18) and the phosphorus ylide derivative represented by the formula (19) is a value within a range of 1: 1 to 1: 3 in terms of molar ratio. It is preferable to do.
The reason for this is that when the addition ratio of the formylated ethenyl derivative and the phosphorus ylide having an ethenyl group is less than 1: 1, the amount of ethenyl derivative represented by the general formula (20) may be reduced. Because there is. On the other hand, when the ratio of addition of the formylated ethenyl derivative and the phosphorus ylide derivative exceeds 1: 3, a large amount of unreacted phosphorus ylide derivative remains, making it difficult to purify the ethenyl derivative represented by the general formula (20). This is because it may become.
Therefore, the addition ratio of the formylated ethenyl derivative represented by the general formula (18) and the phosphorus ylide derivative represented by the formula (19) is a value within a range of 1: 1.2 to 1: 2. More preferably.

In addition, when the formylated enamine derivative represented by the general formula (18) and the phosphorus ylide derivative represented by the formula (19) are reacted, the reaction temperature is usually set to a value within the range of −30 to 25 ° C. At the same time, the reaction temperature is preferably set to a value within the range of 0.2 to 30 hours.
This is because, under such reaction conditions, a desired reaction can be efficiently performed using a relatively simple manufacturing facility.
Examples of the catalyst used in the Witchhi method include metal salts such as n-butyllithium, sodium alkoxides such as sodium methoxide and sodium ethoxide, and metal hydrides such as sodium hydride and potassium hydride. Or the combination of 2 or more types is mentioned.

Next, the ethenyl derivative represented by the general formula (20) is formylated by the second-stage Vilsmeier method to obtain the formylated enamine derivative represented by the general formula (4 ′).
Note that the reaction conditions and the like of the second stage Filsmeier method are preferably performed in accordance with the first stage Filsmeier method in the first step.

2. Triphosphate Derivative Next, a method for synthesizing the triphosphate derivative represented by the general formula (5) as a raw material for carrying out the reaction formula (1) will be described in detail.

  That is, the triphosphate ester derivative represented by the general formula (5) is preferably synthesized as shown in the following reaction formula (3). In addition, A in Reaction Formula (3) has the same contents as A in Reaction Formula (1).

Here, when carrying out the synthesis reaction of such a triphosphate ester derivative, for example, it is preferable to add triethyl phosphite to a trichloromethyl derivative without solvent or in a suitable solvent for reaction. This is because the triphosphate ester derivative (5), which is one of the starting materials of the reaction formula (1), can be obtained in a high yield by reacting in this way.
Moreover, when producing such a synthesis reaction, it is preferable that the use ratio of triethyl phosphite is at least 3 times the molar equivalent per 1 mol of the trichloromethyl derivative, and the value is within the range of 3 to 5 times the molar amount. More preferably.
Moreover, it is preferable to make this reaction temperature into the value within the range of 80-200 degreeC normally, and to make reaction time into the value within the range of 2 to 10 hours.

The solvent used for preparing the triphosphate ester derivative is not particularly limited as long as it does not affect the synthesis reaction. For example, ethers such as diethyl ether, tetrahydrofuran, dioxane, etc .; methylene chloride, chloroform, dichloroethane Preferred examples include halogenated hydrocarbons such as benzene, toluene and other aromatic hydrocarbons, dimethylformamide and the like.
It is also preferable to add a predetermined amount of a tertiary amine when preparing a triphosphate ester derivative. This is because the tertiary amine removes the alkyl halide from the reaction system, so that the synthesis reaction of the triphosphate ester derivative can be promoted. Suitable tertiary amines include, for example, one kind of triethylamine, tributylamine, pyridine, 4- (dimethylamino) pyridine, or a combination of two or more kinds.

3. Reaction condition (1) Reaction temperature and reaction time Moreover, reaction of the formylation enamine derivative represented by General formula (4) and the triphosphate ester derivative represented by General formula (5) is usually -10-30. The reaction is preferably carried out at a temperature of 0 ° C., and the reaction time is preferably set to a value within the range of 1 to 24 hours.

(2) Solvent As a suitable solvent used for the reaction of the formylated enamine derivative represented by the general formula (4) and the triphosphate ester derivative represented by the general formula (5), the reaction is not affected. For example, ethers such as diethyl ether, tetrahydrofuran, and dioxane; halogenated hydrocarbons such as methylene chloride, chloroform, and dichloroethane; and aromatic hydrocarbons such as benzene and toluene can be used.

(3) Base The base used in such a reaction includes sodium alkoxide such as sodium methoxide and sodium ethoxide, metal hydride such as sodium hydride and potassium hydride, or metal salt such as n-butyllithium. Are mentioned as preferred.
Here, it is preferable to make the addition amount of this base into the value within the range of 1.1-5 mol with respect to 1 mol of formylated enamine derivatives.
The reason for this is that when the amount of the base added is less than 1.1 mol, the formylated enamine derivative represented by the general formula (4), the triphosphate ester derivative represented by the general formula (5), This is because the reactivity during the process may be significantly reduced.
On the other hand, when the amount of the base added exceeds 5 mol, the reaction between the formylating enamine derivative represented by the general formula (4) and the triphosphate ester derivative represented by the general formula (5) is controlled. This is because it may be extremely difficult to do.

(4) Addition ratio In carrying out the reaction between the formylated enamine derivative represented by the general formula (4) and the triphosphate ester derivative represented by the general formula (5), It is preferable to set the value within the range of 1: 1 to 6: 1.
The reason for this is that when the ratio of addition of the formylated enamine derivative and the triphosphate derivative is less than 1: 1, an intermediate is easily formed, and the formylated enamine derivative and the triphosphate derivative are This is because it may be difficult to respond appropriately. Moreover, when the addition ratio exceeds 6: 1, a large amount of unreacted formylated enamine derivative remains, which may make purification difficult.
Therefore, the addition ratio of the formylated enamine derivative represented by the general formula (4) and the triphosphate ester derivative represented by the general formula (5) is 1.5: 1 to 5.5 in molar ratio. A value within the range of 1 is preferable.

[Third Embodiment]
The third embodiment is an electrophotographic photosensitive member in which a photosensitive layer is provided on a conductive substrate, and the photosensitive layer contains a stilbene derivative represented by the general formula (1). It is a photoreceptor.
Here, the electrophotographic photosensitive member mainly includes a single layer type photosensitive member and a laminated type photosensitive member, but the stilbene derivative of the present invention is applicable to any type.
However, in particular, it can be used for either positive or negative charge type photoconductors, the structure is simple, the manufacturing is easy, the film defects when forming the photosensitive layer can be effectively suppressed, the interface between the layers is small, For reasons such as easy improvement of optical characteristics, it is preferable to apply to a single layer type photoreceptor.

1. Single Layer Type Photoreceptor (1) Basic Configuration As shown in FIG. 1A, the single layer type photoreceptor 10 is obtained by providing a single photosensitive layer 14 on a conductive substrate 12.
This photosensitive layer is prepared by, for example, dissolving a stilbene derivative (hole transport agent) represented by the general formula (1), a charge generator, a binder resin, and, if necessary, an electron transport agent in an appropriate solvent. Alternatively, it can be formed by dispersing and coating the obtained coating solution on a conductive substrate and drying. Such a single layer type photoreceptor is characterized in that it can be applied to either a positive or negative charge type with a single configuration, has a simple layer configuration, and is excellent in productivity.

Further, since the obtained single-layer type photoreceptor includes the stilbene derivative represented by the general formula (1), the residual potential is lowered and the sensor has a predetermined sensitivity. .
Further, when an electron transport agent is contained in the photosensitive layer of the single-layer type photoreceptor, electrons are efficiently exchanged between the charge generating agent and the hole transport agent, and the sensitivity and the like are more stable. There is a trend.

(2) Charge generator (2) -1 type As the charge generator used in the electrophotographic photosensitive member of the present invention, metal-free phthalocyanine (τ type or X type), titanyl phthalocyanine (α type or Y type), It is preferable to include at least one compound selected from the group consisting of hydroxygallium phthalocyanine (type V) and chlorogallium phthalocyanine (type II).
The reason for this is to provide an electrophotographic photosensitive member with more excellent sensitivity characteristics, electrical characteristics, stability, etc. when a hole transporting agent and an electron transporting agent are used in combination by specifying the type of charge generating agent. It is because it can do.

(2) -2 Specific Examples Among these charge generators, it is more preferable to use phthalocyanine pigments (CGM-A to CGM-D) represented by the following formulas (22) to (25). preferable.

  Moreover, it is also preferable to use a conventionally known charge generating agent alone or in combination. Such charge generators include phthalocyanine pigments such as oxo titanyl phthalocyanine, perylene pigments, bisazo pigments, diketopyrrolopyrrole pigments, metal-free naphthalocyanine pigments, metal naphthalocyanine pigments, squaraine pigments, trisazo pigments, indigo Organic photoconductors such as pigments, azulenium pigments, cyanine pigments, pyrylium pigments, ansanthrone pigments, triphenylmethane pigments, selenium pigments, toluidine pigments, pyrazoline pigments, quinacridone pigments, selenium, selenium-tellurium, selenium- One kind of inorganic photoconductive agent such as arsenic, cadmium sulfide, and amorphous silicon, or a mixture of two or more kinds may be used.

  Among the charge generating agents described above, in particular, when used in a digital optical image forming apparatus such as a laser beam printer or a facsimile provided with a light source such as a semiconductor laser, a photosensitive material having sensitivity in a wavelength region of 700 nm or more. Therefore, it is preferable that at least one of metal-free phthalocyanine, titanyl phthalocyanine, hydroxygallium phthalocyanine, and chlorogallium phthalocyanine is contained.

  On the other hand, when used in an image forming apparatus of an analog optical system such as an electrostatic copying machine equipped with a white light source such as a halogen lamp, a photoreceptor having sensitivity in the visible region is required. Pigments, bisazo pigments and the like are preferably used.

Moreover, when using the compound (CGM-B) represented by the formula (23) described above among the charge generating agents used in the present invention, a dispersion aid represented by the following formula (26) (for example, C. IPigment Orange 16) may be added.
This is because the charge generating agent (CGM-B) and the dispersion auxiliary agent (C. IPigment Orange 16) are used together to improve the dispersibility of CGM-B in the coating solution, and the coating solution pot This is because the life can be lengthened.
In addition, when using the dispersion | distribution adjuvant represented by Formula (26), it is preferable to make the addition amount into the value within the range of 30-200 weight part with respect to 100 weight part of all the electric charge generating agents.
The reason for this is that when the amount of the dispersion aid added is less than 30 parts by weight, dispersibility in the coating solution of CGM-B becomes insufficient, and an appropriate film as a photoreceptor cannot be produced. is there. On the other hand, when the dispersion aid exceeds 200 parts by weight, the effect of increasing the quantum yield of the charge generating agent becomes insufficient, and the sensitivity characteristics, electrical characteristics, stability, etc. of the electrophotographic photoreceptor can be improved. It is because it becomes impossible.

(3) Hole transport agent In the electrophotographic photoreceptor of the present invention, it is also preferable that the photosensitive layer contains another conventionally known hole transport agent together with the stilbene derivative of the present invention which is a hole transport agent.
Examples of such hole transporting agents include various compounds having high hole transporting ability, for example, compounds represented by the following general structural formulas (27) to (39) (HTM-1 to HTM-13). .

(Wherein R ^h1 , R ^h2 , R ^h3 , R ^h4 , R ^h5 and R ^h6 are independent of each other, and are a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, substituted or An unsubstituted aryl group having 6 to 40 carbon atoms, a and b are the same or different integers of 0 to 4, and c, d, e and f are the same or different 0 Represents an integer of ˜5, provided that when a, b, c, d, e or f is 2 or more, each R ^h1 , R ^h2 , R ^h3 , R ^h4 , R ^h5 and R ^h6 may be different. .)

(Wherein R ^h7 , R ^h8 , R ^h9 , R ^h10 and R ^h11 are independent of each other, and are a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted group, An aryl group having 6 to 40 carbon atoms, wherein g, h, i and j represent the same or different integers of 0 to 5 and k represents an integer of 0 to 4, provided that g, h , I, j or k is 2 or more, each R ^h7 , R ^h8 , R ^h9 , R ^h10 and R ^h11 may be different.)

^{(Wherein, R h12, R h13, R} h14 and R ^h15 are independent of each other, substituted or unsubstituted alkyl or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted C 6 to 40 carbon ^{Represents an} aryl group, and R ^h16 represents a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms. M, n, o and p represent the same or different integers of 0 to 5, and q represents an integer of 0 to 6, provided that m, n, o, p or q is 2 or more. when each ^{R h12, R h13, R h14} , R h15 and R ^h16 may be different.)

( ^Wherein R ^h17 , R ^h18 , R ^h19 and R ^h20 are independent of each other, and are a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted carbon number of 6; Represents an aryl group of ˜40, r, s, t, and u represent the same or different integers of 0 to 5, provided that when r, s, t, or u is 2 or more, each R ^h17, R ^h18, R ^h19 and R ^h20 may be different.)

(In the formula, R ^h21 and R ^h22 are independent of each other and represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms or an alkoxy group. R ^h23 , R ^h24 , R ^h25 and R ^h26 are independent of each other. And represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 40 carbon atoms.)

(In the formula, R ^h27 , R ^h28 and R ^h29 are independent of each other and represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms or an alkoxy group.)

(In the formula, R ^h30 , R ^h31 , R ^h32 and R ^h33 are independent of each other and represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms or an alkoxy group.)

(In the formula, R ^h34 , R ^h35 , R ^h36 , R ^h37 and R ^h38 are independent of each other and represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms or an alkoxy group.)

(In the formula, R ^h39 represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, R ^h40 , R ^h41 and R ^h42 are independent of each other; a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms; Or an alkoxy group.)

(Wherein, R ^h43, R ^h44 and R ^h45 are independent of each other, represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group having 1 to 20 carbon atoms.)

(In the formula, R ^h46 and R ^h47 are independent of each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted carbon atom having 6 to 6 carbon atoms. 40 aryl groups are shown.)

(In the formula, R ^h50 , R ^h51 , R ^h52 , R ^h53 , R ^h54 and R ^h5 are independent of each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or an alkoxy group. Or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, α represents an integer of 1 to 10, and v, w, x, y, z and β may be the same or different. Represents an integer of 0 to 2, provided that when v, w, x, y, z or β is 2, each R ^h50 , R ^h51 , R ^h52 , R ^h53 , R ^h54 and R ^h55 may be different. .)

(In the formula, R ^h56 , R ^h57 , R ^h58 and R ^h59 are independent of each other, and represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, and Φ is It is a group represented by any of the formulas.)

  Further, in the present invention, together with the above exemplified hole transport agents HT-1 to HT-13 and the like, a conventionally known hole transport material, 2,5-di (4-methylaminophenyl) -1,3,4 Oxadiazole compounds such as oxadiazole, styryl compounds such as 9- (4-diethylaminostyryl) anthracene, carbazole compounds such as polyvinylcarbazole, organic polysilane compounds, 1-phenyl-3- (p-dimethylamino) Pyrazoline compounds such as phenyl) pyrazoline, hydrazone compounds, triphenylamine compounds, indole compounds, oxazole compounds, isoxazole compounds, thiazole compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds, triazole compounds Nitrogen-containing cyclic compounds such as compounds, condensation Singly or in combinations of two or more such cyclic compounds.

(4) Electron Transfer Agent (4) Electron Transfer Agent As the electron transfer agent used in the present invention, a compound containing a quinone derivative is preferable. This is because, by using a specific compound as an electron transport agent, the electron acceptability is excellent and the compatibility with the charge generating agent is excellent. This is because it is possible to provide an electrophotographic photoreceptor excellent in the above.

  Specific examples of these electron transfer agents include compounds (ETM-A to ETM-C) represented by the following formulas (41) to (43).

  In addition, as the electron transport agent used in the present invention, it is also preferable to include other conventionally known electron transport agents in the photosensitive layer. Examples of such an electron transport agent include various compounds having high electron transport ability, for example, compounds represented by the following general structural formulas (44) to (60) (ETM-1 to ETM-17).

(Wherein R ^e1 , R ^e2 , R ^e3 , R ^e4 and R ^e5 are independent of each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, substituted or An unsubstituted aryl group having 6 to 40 carbon atoms or an aralkyl group, or a substituted or unsubstituted phenoxy group.

(In the formula, R ^e6 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, R ^e7 is a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted carbon group having 6 to 6 carbon atoms. 40 represents an aryl group or an aralkyl group, a halogen atom, or a halogenated alkyl group, and γ represents an integer of 0 to 5. However, when γ is 2 or more, each R ^e7 may be different from each other. )

(In the formula, R ^e8 and R ^e9 are independent of each other, and represent a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Δ represents an integer of 1 to 4, and ε represents an integer of 0 to 4. (However, when δ and ε are 2 or more, each R ^e8 and R ^e9 may be different.)

( ^Wherein R ^e10 represents a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group or aralkyl group having 6 to 40 carbon atoms, a halogenated alkyl group, or a halogen atom. Ζ represents an integer of 0 to 4, and η represents an integer of 0 to 5. However, when η is 2 or more, each R ^e10 may be different.)

(In the formula, R ^e11 represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and σ represents an integer of 1 to 4. However, when σ is 2 or more, each R ^e11 may be different. good.)

( ^Wherein R ^e12 and R ^e13 are independent of each other, a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted carbon group having 6 to 40 carbon atoms) An aryl group, an aralkyloxycarbonyl group, a hydroxyl group, a nitro group, or a cyano group, and X represents an oxygen atom, = N-CN group, or = C (CN) ₂ group.

( ^Wherein R ^e14 represents a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, and R ^e15 represents a halogen ^atom. An atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, an alkoxycarbonyl group, an N-alkylcarbamoyl group, a cyano group, or a nitro group is represented. ^Represents an integer of 0 to 3. However, when λ is 2 or more, each ^{Re 15} may be different from each other.

(In the formula, θ represents an integer of 1 to 2)

(In the formula, R ^e16 and R ^e17 are independent of each other, and represent a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a cyano group, a nitro group, or an alkoxycarbonyl group. Represents an integer of ˜3, provided that when ν or ξ is 2 or more, R ^e16 and R ^e17 may be different from each other.

(In the formula, R ^e18 and R ^e19 are independent of each other, and represent a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, a condensed polycyclic group or a heterocyclic group, and these groups represent a substituent. You may have.)

( ^Wherein R ^e20 represents an amino group, a dialkylamino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or an alkoxy group, or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, and π represents ^Represents an integer of 1 to 2. However, when π is 2, each ^{Re 20} may be different from each other.

(In the formula, R ^e21 represents a hydrogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group or aralkyl group having 6 to 40 carbon atoms.)

( ^Wherein R ^e22 represents a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group or aralkyl group having 6 to 40 carbon atoms, an alkoxycarbonyl group, N -Represents an alkylcarbamoyl group, a cyano group, or a nitro group, and μ represents an integer of 0 to 3. However, when μ is 2 or more, each ^{Re 22} may be different from each other.

(Wherein, R ^e23 represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms having 1 to 20 carbon atoms, R ^e24 represents a substituted or unsubstituted C 1 -C 20 alkyl group or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms or a group represented by -O-R ^e24,. R ^e24 in the above groups, the above-described substituted or unsubstituted carbon Represents an alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms.)

(In the formula, R ^e25 , R ^e26 , R ^e27 , R ^e28 , R ^e29 , R ^e30 and R ^e31 are independent of each other, and are substituted or unsubstituted alkyl or alkoxy groups having 1 to 20 carbon atoms, substituted or An unsubstituted aryl group having 6 to 40 carbon atoms or an aralkyl group, a halogen atom, or a halogenated alkyl group, and χ and φ are the same or different integers of 0 to 4.

( ^Wherein R ^e32 and R ^e33 are independent of each other, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, a halogen atom, Or a halogenated alkyl group, wherein τ and ψ are the same or different and represent an integer of 0 to 4.

( ^Wherein R ^e34 , R ^e35 , R ^e36 and R ^e37 are independent of each other, and are a hydrogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted carbon number of 6; An aryl group, an aralkyl group, a cycloalkyl group or an amino group of ^˜40 , ^provided that at least two of R ^e34 , R ^e35 , R ^e36 and R ^e37 are the same group which is not a hydrogen atom.

  In addition to the above examples, in the present invention, conventionally known electron transport materials, for example, benzoquinone compounds, malononitrile, thiopyran compounds, tetracyanoethylene, 2,4,8-trinitrothioxanthone, dinitrobenzene, dinitroanthracene, etc. , Dinitroacridine, nitroanthraquinone, dinitroanthraquinone, succinic anhydride, maleic anhydride, dibromomaleic anhydride, etc., alone or in combination.

(5) Binder Resin As the binder resin for dispersing each component, various resins conventionally used for photosensitive layers can be used. For example, styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, acrylic copolymer, styrene-acrylic acid copolymer, polyethylene resin, ethylene-vinyl acetate copolymer, chlorinated polyethylene Resin, polyvinyl chloride resin, polypropylene resin, ionomer resin, vinyl chloride-vinyl acetate copolymer, polyester resin, alkyd resin, polyamide resin, polyurethane resin, polycarbonate resin, polyarylate resin, polysulfone resin, diallyl phthalate resin, ketone resin , Polyvinyl butyral resin, polyether resin, polyester resin, etc .; silicone resin, epoxy resin, phenol resin, urea resin, melamine resin, other crosslinkable thermosetting resins; epoxy acrylate DOO, urethane - resin such as photocurable resin such as acrylate can be used.
In particular, a polycarbonate resin is a preferable binder resin because it is excellent not only in transparency and heat resistance but also in mechanical properties and compatibility with a hole transport agent.

(6) Additives In addition to the above-mentioned components, the photosensitive layer contains various conventionally known additives such as antioxidants, radical scavengers, singlet quenchers, and the like within a range that does not adversely affect the electrophotographic characteristics. Deterioration inhibitors such as char and ultraviolet absorbers, softeners, plasticizers, surface modifiers, extenders, thickeners, dispersion stabilizers, waxes, acceptors, donors, and the like can be blended. In order to improve the sensitivity of the photosensitive layer, a known sensitizer such as terphenyl, halonaphthoquinones, and acenaphthylene may be used in combination with the charge generator.

(7) Mixing ratio and thickness When the electrophotographic photosensitive member of the present invention is a single-layer type photosensitive member, the charge generating agent is 0.1 to 50 parts by weight, preferably 100 parts by weight of the binder resin. What is necessary is just to mix | blend in the ratio of 0.5-30 weight part. In addition, the stilbene derivative (hole transport agent) represented by the general formula (1) of the present invention is blended in an amount of 20 to 500 parts by weight, preferably 30 to 200 parts by weight with respect to 100 parts by weight of the binder resin. Just do it. When the electron transport agent is contained, the ratio of the electron transport agent is 5 to 100 parts by weight, preferably 10 to 80 parts by weight with respect to 100 parts by weight of the binder resin.
In addition, when the electrophotographic photoreceptor of the present invention is a laminated photoreceptor, the charge generator and the binder resin constituting the charge generation layer can be used in various ratios, but the binder resin 100 can be used. It is appropriate to mix the charge generating agent in an amount of 5 to 1000 parts by weight, preferably 30 to 500 parts by weight with respect to parts by weight. Furthermore, when the hole transport agent is contained in the charge generation layer, the ratio of the hole transport agent is 10 to 500 parts by weight, preferably 50 to 200 parts by weight with respect to 100 parts by weight of the binder resin. It is.

  The hole transport agent constituting the charge transport layer and the binder resin can be used in various proportions within a range that does not inhibit charge transport and a range that does not crystallize. 10 to 500 parts by weight, preferably 25, of the stilbene derivative (hole transport agent) represented by the general formula (1) of the present invention with respect to 100 parts by weight of the binder resin so that the charges can be easily transported. It is appropriate to blend at a ratio of ~ 200 resin. When the charge transport layer contains an electron transport agent, the ratio of the electron transport agent is 5 to 200 parts by weight, preferably 10 to 100 parts by weight, based on 100 parts by weight of the binder resin.

(8) Structure Further, the thickness of the photosensitive layer in the single-layer type photoreceptor is 5 to 100 μm, preferably 10 to 50 μm.
As the conductive substrate on which such a photosensitive layer is formed, various materials having conductivity can be used, for example, iron, aluminum, copper, tin, platinum, silver, vanadium, molybdenum, chromium, Examples thereof include metals such as cadmium, titanium, nickel, palladium, indium, stainless steel, and brass, plastic materials on which the above metal is vapor-deposited or laminated, glass coated with aluminum iodide, tin oxide, indium oxide, and the like.

  The shape of the conductive substrate may be any of a sheet shape and a drum shape according to the structure of the image forming apparatus to be used. The substrate itself has conductivity or the surface of the substrate has conductivity. If you do. The conductive substrate preferably has sufficient mechanical strength when used. When the photosensitive layer is formed by a coating method, the charge generator, charge transport agent, binder resin and the like exemplified above, together with a suitable solvent, a known method such as a roll mill, ball mill, attritor, paint shaker, super A dispersion liquid may be prepared by dispersing and mixing using a sonic disperser or the like, and this may be applied and dried by a known means.

  Further, regarding the configuration of the single-layer type photoreceptor 10, as shown in FIG. 1B, a barrier layer 16 is formed between the conductive substrate 12 and the photosensitive layer 14 as long as the characteristics of the photoreceptor are not impaired. May be. Further, as shown in FIG. 1C, a protective layer 18 may be formed on the surface of the photosensitive layer 14.

(9) Production method Various organic solvents can be used as a solvent for preparing the dispersion. For example, alcohols such as methanol, ethanol, isopropanol and butanol; aliphatic systems such as n-hexane, octane and cyclohexane Hydrocarbons: aromatic hydrocarbons such as benzene, toluene, xylene, halogenated hydrocarbons such as dichloromethane, dichloroethane, chloroform, carbon tetrachloride, chlorobenzene; ethers such as dimethyl ether, diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether Ketones such as acetone, methyl ethyl ketone and cyclohexanone; esters such as ethyl acetate and methyl acetate; dimethylformaldehyde, dimethylformamide, dimethylsulfo Sid and the like. These solvents are used alone or in admixture of two or more.
Further, a surfactant, a leveling agent or the like may be used in order to improve the dispersibility of the charge transport agent or charge generator and the smoothness of the photosensitive layer surface.

2. Multilayer Photoreceptor As shown in FIG. 2A, the multilayer photoreceptor 20 is formed by forming a charge generation layer 24 containing a charge generation agent on a conductive substrate 12 by means of vapor deposition or coating, Next, a coating liquid containing at least one stilbene derivative (hole transport agent) represented by the general formula (1) and a binder resin is applied onto the charge generation layer 24 and dried to be the charge transport layer 22. It is produced by forming.
In contrast to the above structure, as shown in FIG. 2B, the charge transport layer 22 may be formed on the conductive substrate 12, and the charge generation layer 24 may be formed thereon.
However, since the charge generation layer 24 is much thinner than the charge transport layer 22, for protection, the charge transport layer 22 is formed on the charge generation layer 24 as shown in FIG. It is more preferable to form
The charge generating agent, hole transporting agent, electron transporting agent, binder and the like can be the same as those of the single layer type photoreceptor.

In addition, a positive or negative charge type is selected depending on the formation order of the charge generation layer and the charge transport layer and the kind of the charge transport agent used in the charge transport layer. For example, as described above, when a charge generation layer is formed on a conductive substrate and a charge transport layer is formed thereon, a hole such as the stilbene derivative of the present invention is used as a charge transport agent in the charge transport layer. When a transport agent is used, the photoreceptor is a negatively charged type. In this case, the charge generation layer may contain an electron transport agent.
The multilayer electrophotographic photosensitive member of the present invention is characterized in that the residual potential of the photosensitive member is lowered and that it has a predetermined sensitivity.
The thickness of the photosensitive layer in the multilayer photoconductor is about 0.01 to 5 μm, preferably about 0.1 to 3 μm for the charge generation layer, and about 2 to 100 μm, preferably about 5 to 50 μm for the charge transport layer. It is.

  Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples.

[Example 1]
(1) Synthesis of Stilbene Derivative (HTM-A) Represented by Formula (9) (1) -1 Synthesis of Triphosphate Derivative Derivative The synthesis of the triphosphate ester derivative represented by Formula (62) is represented by the following reaction formula ( Synthesized according to 4). That is, after adding 67.1 g (0.30 mol) of 1,3,5-tris (chloromethyl) benzene into a flask having a volume of 500 ml, 166 g (0.99 mol) of phosphorous acid triethyl ester was added, and 170 ° C. The mixture was refluxed for 8 hours. Next, a white precipitate was obtained by cooling to room temperature, and the white precipitate obtained using hexane was washed and then vacuum-dried to obtain 121.4 g of a triphosphate ester derivative (yield 76. 6%).

(1) -2 Synthesis of Diphenyl Enamine Derivative Synthesis of the diphenyl enamine compound represented by Formula (65) was carried out according to the following Reaction Formula (5).
That is, in a 300 ml flask, 13 g (0.077 mol) of the aniline derivative represented by the formula (63), 15.1 g (0.077 mol) of diphenylacetaldehyde represented by the formula (64), 150 ml of toluene, , P-toluenesulfonic acid monohydrate 3.0 g (0.015 mol) was stored, immersed in an oil bath, heated to 130 ° C., and refluxed for 2 hours to perform formylation. . Next, after cooling to room temperature, anhydrous sodium sulfate was added and dried, and an adsorption treatment by an activated clay treatment was performed. Next, after filtration, toluene was distilled off under reduced pressure, and the resulting residue was added to methanol and stirred hot. After cooling, the crystalline substance was filtered off and dried to obtain 23.8 g of a diphenylenamine derivative represented by the formula (65) (yield 88.8%).

(1) -3 Synthesis of Formylated Diphenyl Enamine Derivative Next, synthesis of a formylated diphenyl enamine derivative represented by the formula (66) was performed according to the following reaction formula (6).
That is, 21.2 g (0.061 mol) of the diphenylamine compound represented by the formula (65), 200 ml of dimethylformamide (DMF), and 14 g (0.092 mol) of oxychlorophosphoric acid are accommodated in a 500 ml flask. And reacted at 95 ° C. for 1 hour. After completion of the reaction, 600 ml of ion-exchanged water was dropped, followed by filtration to take out the precipitate. The obtained precipitate was dissolved in toluene and extracted as an organic layer. Next, the organic layer was washed with water and dried using anhydrous sodium sulfate, and then the dried product was purified by silica gel column chromatography (developing solvent: chloroform solvent) to obtain a formylated diphenyl enamine represented by the formula (66). 18.4 g of the derivative was obtained (yield 80.2%).

(1) -4 Synthesis of Stilbene Derivative Next, a stilbene derivative represented by the formula (9) was synthesized according to the following reaction formula (7).
That is, in a 500 ml two-necked flask, 1.06 g (2 mmol) of the triphosphate ester derivative represented by the formula (62) obtained in (1) -1 was added, purged with argon, and dehydrated THF 50 ml. Was added. Next, 4.86 g (0.025 mol) of NaOMe having a concentration of 28% / 20 ml of THF was added, and the mixture was stirred for about 20 minutes until uniform. Next, in this two-necked flask, 2.64 g (7 mmol) of the formylated diphenylenamine derivative represented by the formula (66) obtained in (1) -3 was dissolved in 50 ml of THF, and then added dropwise to a funnel. For about 12 hours. Subsequently, it mixed with 400 ml of about 2% dilute hydrochloric acid aqueous solution, toluene was added with respect to the isolate | separated water layer, and the extraction process was implemented. The obtained organic layer was washed with ion-exchanged water, and anhydrous sodium sulfate and activated clay were further added, followed by drying and adsorption treatment. Thereafter, toluene was distilled off under reduced pressure, and the residue was purified by silica gel chromatography (developing solvent: chloroform / n-hexane = 1/1), and further subjected to reprecipitation treatment using toluene / n-hexane to obtain the formula (9 1.33 g of a stilbene derivative represented by the following formula was obtained (yield: 55.9%).

(2) Evaluation (2) -1 Measurement of Initial Surface Potential, Half-Exposure Exposure and Residual Potential Using the obtained stilbene derivative as a hole transport agent, a single-layer type electrophotographic photosensitive member was prepared, and the initial surface potential, Half exposure and residual potential were measured. That is, 100 parts by weight of the obtained stilbene derivative as a hole transport agent and 5 parts by weight of an X-type metal-free phthalocyanine (CGM-A) represented by the formula (22) as a charge generator As a resin, 100 parts by weight of a polycarbonate resin represented by the following formula (67) was added to 800 parts by weight of tetrahydrofuran as a solvent. Subsequently, it was mixed and dispersed for 50 hours using a ball mill to prepare a coating solution for a single-layer type photosensitive layer. The obtained coating solution is applied onto a conductive substrate (aluminum tube) by a dip coating method, dried with hot air at 100 ° C. for 30 minutes, and a single layer type electrophotographic film having a thickness of 25 μm. A photoreceptor was obtained.
Next, the initial electric characteristics in the obtained electrophotographic photosensitive member, that is, the half exposure amount (E _1/2 ) and the residual potential (Vr) were measured using a drum sensitivity tester (manufactured by GENTEC) with a surface potential of 700 V. The measurement was carried out by electrification. The surface potential upon charging is shown in Table 1 as the initial surface potential (Vo).
In addition, for half exposure (E _1/2 ), monochromatic light having a wavelength of 780 nm (half-value width: 20 nm, light intensity: 1.5 μJ / cm ² ) extracted from the light of a halogen lamp using a bandpass filter, The surface of the photoreceptor was irradiated for 1.5 seconds, and the time required for the initial surface potential (Vo) to be halved was measured. Further, regarding the residual potential (Vr), the surface potential at the time when 330 msec has elapsed from the start of exposure was measured, and the value was defined as the residual potential (Vr).
The obtained results are shown in Table 1.

[Examples 2 to 4]
In Examples 2 to 4, 30 parts by weight of quinone derivatives (ETM-A to C) represented by the following formulas (41) to (43) were added to the coating liquid of Example 1 as electron transport agents. Otherwise, a single-layer type photosensitive layer was prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 1.

[Examples 5 to 8]
In Examples 5 to 8, a single layer was formed in the same manner as in Examples 1 to 4, except that the stilbene derivative (HTM-B) represented by the formula (10) was used as the hole transport agent in Examples 1 to 4. Type photoreceptors were prepared and evaluated. The obtained results are shown in Table 1.

[Comparative Examples 1-4]
Comparative Examples 1 to 4 are the same as Examples 1 to 4, except that the triphenylamine compound (HTM-J) represented by the following formula (68) was used as the hole transport agent in Examples 1 to 4. A single-layer type photosensitive layer was prepared and evaluated. The obtained results are shown in Table 1.

[Comparative Examples 5-6]
In Comparative Examples 5 to 6, the same procedure as in Examples 1 and 2 except that a triphenylamine compound (HTM-K) represented by the following formula (69) was used as the hole transport agent in Examples 1 and 2. A single-layer type photosensitive layer was prepared and evaluated. The obtained results are shown in Table 1.

得られた結果を表１に示す。

The obtained results are shown in Table 1.

[Example 9]
In Example 9, the stilbene derivative (HTM-D) represented by the formula (12) was prepared and evaluated according to Example 1.

(1) Preparation of stilbene derivative (HTM-D) (1) -1 Preparation of triphosphate ester derivative Preparation of the triphosphate ester derivative represented by the formula (62) is carried out in the same manner as in Example 1 except that the reaction formula (4 ).

(1) -2 Synthesis of Diphenyl Enamine Derivative The synthesis of the diphenyl enamine compound represented by Formula (65) was performed according to Reaction Formula (5) in the same manner as Example 1.

(1) -3 Synthesis of Formylated Diphenyl Enamine Derivative Next, the synthesis of the diphenyl enamine derivative represented by the formula (67) was carried out according to the reaction formula (6) in the same manner as in Example 1.

(1) -4 Synthesis of phosphorus ylide Subsequently, the synthesis of phosphorus ylide represented by the formula (71) was carried out according to the following reaction formula (8). That is, 500 g (2.47 mol) of 1-diphenylchloromethane represented by the formula (70) and 492 g (3.00 mol) of phosphorous acid triethyl ester were added and heated at 160 ° C. for 3 hours. While stirring. Then, after cooling to room temperature, the precipitated white solid was filtered off. The obtained solid was washed with n-hexane and then crystallized with chloroform-n-hexane to obtain 639 g of phosphorus ylide represented by the formula (71) (yield 85%).

(1) -5 Synthesis of diphenylamine derivative Subsequently, a diphenylamine derivative represented by the following formula (72) was synthesized according to the following reaction formula (9). That is, after accommodating 18.3 g (0.06 mol) of phosphorus ylide represented by the formula (71) in a 1000 ml four-necked flask, argon gas substitution was performed, and further at 5 ° C. or less, 100 ml of THF was added, Further, 37.5 ml of n-BuLi hexane solution (concentration: 1.6 mol / liter) was added dropwise and stirred for 10 minutes. Furthermore, 15 g (0.04 mol) of formylated triphenylamine derivative represented by the formula (66) / 45 ml of THF were added at −20 ° C. or lower, and the reaction was allowed to proceed with stirring for 30 minutes. The obtained reaction solution was poured into ion-exchanged water and extracted with toluene. Further, the organic layer containing toluene was repeatedly washed 5 times with ion-exchanged water, and then dried and adsorbed with anhydrous sodium sulfate and activated clay. Thereafter, the solvent was distilled off, and the mixture was allowed to stand at room temperature for 2 days. The obtained precipitated solid was filtered off using petroleum ether and dried under reduced pressure to obtain 13.8 g of a diphenylamine derivative represented by the formula (72) (yield 65.6%).

(1) -6 Synthesis of Formylated Diphenylamine Derivative Next, synthesis of a formylated diphenylamine derivative represented by the following formula (73) was performed according to the following reaction formula (10).
That is, in a 500 ml flask, 12 g (0.0228 mol) of the diphenylamine compound represented by the formula (72), 100 ml of dimethylformamide (DMF), and 5.25 g (0.0342 mol) of oxychlorophosphoric acid were accommodated. The reaction was carried out at 85 ° C. for 30 minutes. After completion of the reaction, the reaction solution was added dropwise to a mixed solution of 400 ml of ion exchange water and 200 ml of toluene, and then the obtained toluene layer was washed with ion exchange water. Furthermore, the obtained organic layer was dried and adsorbed using anhydrous sodium sulfate and activated clay. Thereafter, the dried product was purified by silica gel column chromatography (developing solvent: chloroform solvent) to obtain 77.6 g of a formylated diphenylenamine derivative represented by the formula (73) (yield: 9.8%).

(1) -7 Synthesis of Stilbene Derivative Next, a stilbene derivative (HTM-D) represented by the formula (12) was synthesized according to the following reaction formula (11).
That is, 2.91 g (0.00429 mol) of the triphosphate ester derivative represented by the formula (62) obtained in (1) -1 was added to a 500 ml two-necked flask and purged with argon, followed by dehydration treatment. 50 ml of THF was added. Then, 28% NaOMe 3.98 g (0.0206 mol) / 20 ml of THF was added, and the mixture was stirred at room temperature for about 20 minutes until uniform. Next, 9.5 g (0.0172 mol) of the formylated diphenylenamine derivative represented by the formula (73) obtained in (1) -6 was dissolved in 50 ml of THF in this two-necked flask, and then added dropwise to the funnel. And allowed to react at room temperature for about 12 hours. Subsequently, toluene was added and the extraction process was implemented. The obtained organic layer was washed with ion-exchanged water, and anhydrous sodium sulfate and activated clay were further added, followed by drying and adsorption treatment. Thereafter, toluene was distilled off under reduced pressure, and the residue was purified by silica gel chromatography (developing solvent: chloroform / n-hexane = 1/1), and further subjected to reprecipitation treatment using toluene / n-hexane. 3.9 g of a stilbene derivative represented by the following formula was obtained (yield 39.9%):

(2) Preparation and Evaluation of Electrophotographic Photoreceptor In Example 5, instead of the stilbene derivative (HTM-A) represented by formula (9) as a hole transport agent in the coating liquid of Example 1, An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1 except that the stilbene derivative (HTM-D) represented by the formula (12) was used. The obtained results are shown in Table 2.

[Examples 10 to 12]
In Examples 10-12, the stilbene derivative (HTM-D) represented by Formula (12) was used as the hole transport agent in the coating liquid of Example 1, and the following formula was used as the electron transport agent. A single-layer photosensitive layer was prepared and evaluated in the same manner as in Example 1 except that 30 parts by weight of the quinone derivatives (ETM-A to C) represented by (41) to (43) were added. The obtained results are shown in Table 2.

[Examples 13 to 16]
In Examples 13 to 16, except that the stilbene derivatives (HTM-F to I) represented by the formulas (14) to (17) were added to the coating liquid of Example 2 as hole transport agents, An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 2. The obtained results are shown in Table 2.

As described above in detail, the stilbene derivative represented by the general formula (1) of the present invention has compatibility with the binder resin by symmetrically introducing an enamine structure at three predetermined positions in the molecule. It is excellent and has a high charge transport ability (hole transport ability) over a long period of time as well as the initial stage.
The electrophotographic photoreceptor of the present invention has a predetermined sensitivity and durability because the stilbene derivative represented by the general formula (1) is used as a hole transport agent. Therefore, the electrophotographic photosensitive member of the present invention is expected to contribute to speeding up and high performance of various image forming apparatuses such as copying machines and printers.
Furthermore, since the stilbene derivative represented by the general formula (1) has a high hole transporting ability, it is suitably used as a hole transporting agent in an electrophotographic photosensitive member, as well as in a solar cell, an electroluminescence element, and the like. Can be used in various fields.

(A)-(c) is a figure provided in order to demonstrate the basic structure and deformation | transformation structure of a single layer type photoreceptor. (A)-(b) is a figure provided in order to demonstrate the basic structure and deformation | transformation structure of a laminated type photoreceptor.

Explanation of symbols

10: Single layer type photoreceptor 12: Conductive substrate 14: Photosensitive layer 16: Barrier layer 18: Protective layer 20: Multilayer type photoreceptor 22: Charge transport layer 24: Charge generation layer

Claims (8)

A stilbene derivative having three enamine structures, which is represented by the following general formula (1):

(In General Formula (1), A is a trivalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁷ , B ¹ and B ² are each an independent hydrogen atom, Halogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, carbon number 6 -20 substituted or unsubstituted aryl group, substituted or unsubstituted amino group, substituted or unsubstituted ethenyl group having 2 to 30 carbon atoms, substituted or unsubstituted styryl group having 8 to 20 carbon atoms, or plural B ¹ and B ^{2 of the above} are a substituted or unsubstituted carbocyclic structure formed by bonding or condensation.) The stilbene derivative according to claim 1, wherein the trivalent organic group represented by the symbol A in the general formula (1) is an organic group represented by the following general formula (2).

(In General Formula (2), R ^{8 to} R ¹⁹ are each independently an hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted halogen group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms.) A plurality of R ¹ , R ² , R ⁴ , R ⁵ , R ⁶ and R ^{7 in the} general formula (1) are each an independent hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. The stilbene derivative according to claim 1, wherein the stilbene derivative is present. A plurality of R ³ in the general formula (1) are each an independent hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituent represented by the following general formula (3). The stilbene derivative according to claim 1, wherein

(In General Formula (3), R ^{20 to} R ²⁶ are each an independent hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and a substituted or unsubstituted halogen group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms.) A method for producing a stilbene derivative having three enamine structures represented by reaction formula (1), comprising a formylated enamine derivative represented by general formula (4) and a triphosphate ester represented by formula (5) A method for producing a stilbene derivative, which comprises reacting a derivative with a base in the presence of a base to obtain a stilbene derivative having three enamine structures represented by the general formula (1).

(In the reaction formula (1), A is a trivalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁷ , B ¹ and B ² are each an independent hydrogen atom, Halogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, carbon number 6 -20 substituted or unsubstituted aryl group, substituted or unsubstituted amino group, substituted or unsubstituted ethenyl group having 2 to 30 carbon atoms, substituted or unsubstituted styryl group having 8 to 20 carbon atoms, or plural B ¹ and B ² are a substituted or unsubstituted carbocyclic structure formed by bonding or condensation. As the formylated enamine derivative represented by the general formula (4), as shown in the following reaction formula (2), an aniline derivative represented by the general formula (6) and an acetaldehyde derivative represented by the general formula (7) And a formylated enamine derivative obtained by formylation by the Vilsmeier method after obtaining an enamine derivative represented by the general formula (8). 6. A method for producing a stilbene derivative according to 5.

(In the reaction formula (2), a plurality of R ^{1 to} R ⁷ , B ¹ and B ² are each an independent hydrogen atom, halogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, 20 substituted or unsubstituted alkyl halide groups, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted aryl group having 6 to 20 carbon atoms, substituted or unsubstituted amino group, carbon number A substituted or unsubstituted ethenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted styryl group having 8 to 20 carbon atoms, or a substituted or unsubstituted carbon formed by bonding or condensing a plurality of B ¹ and B ² It is a ring structure. An electrophotographic photosensitive member having a photosensitive layer provided on a conductive substrate, wherein the photosensitive layer contains a stilbene derivative having three enamine structures represented by the following general formula (1): Photoconductor.

(In General Formula (1), A is a trivalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁷ , B ¹ and B ² are each an independent hydrogen atom, Halogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, carbon number 6 -20 substituted or unsubstituted aryl group, substituted or unsubstituted amino group, substituted or unsubstituted ethenyl group having 2 to 30 carbon atoms, substituted or unsubstituted styryl group having 8 to 20 carbon atoms, or plural B ¹ and B ^{2 of the above} are a substituted or unsubstituted carbocyclic structure formed by bonding or condensation.)   The electrophotographic photoreceptor according to claim 7, wherein the photosensitive layer is a single layer type further containing a charge generating agent and an electron transporting agent.

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