JP2007254301A - Arylamine derivative, method for producing the same and electrophotographic photoreceptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an arylamine derivative having excellent solubility in solvents and compatibility with a binding resin and good sensitivity and maintaining prescribed sensitivity over a long period, to provide a method for producing the arylamine derivative and to provide an electrophotographic photoreceptor. <P>SOLUTION: The arylamine derivative is represented by general formula (I) (wherein, R<SP>1</SP>to R<SP>15</SP>are each same or different and are each a hydrogen atom, a halogen atom, an alkyl group which may be substituted, an alkoxy group which may be substituted, an aryl group which may be substituted or an aralkyl group which may be substituted; and Ar is same or different and is an alkyl group which may be substituted, an aryl group which may be substituted or a heterocyclic group which may be substituted). The electrophotographic photoreceptor is obtained by using the arylamine derivative. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an arylamine derivative, a method for producing the same, and an electrophotographic photoreceptor.

  Conventionally, as an electrophotographic photoreceptor for wet development used in an image forming apparatus or the like, an organic photoreceptor made of an organic photoreceptor material such as a charge transport agent, a charge generator, 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 an inorganic photoreceptor.

  Among these organophotoreceptor materials, the charge transport material having a predetermined charge mobility is represented by the following formula:

(In the formula, Rr ¹ and Rr ² represent an alkyl group containing a substituted alkyl group or an aryl group containing a substituted aryl group, and Ark represents an aryl group containing a substituted aryl group.)
There is known a styryl compound having two identical substituents on the amino group represented by (for example, see Patent Document 1).
JP 60-175052 (Claims)

  However, since the compound described in Patent Document 1 has insufficient charge mobility, when used as a charge transport material in an electrophotographic photoreceptor, sensitivity is insufficient and solubility in a solvent and There was a problem that the compatibility with the binder resin was poor.

  The present invention has been made in view of the above problems, and is an arylamine that is excellent in solubility in a solvent and compatibility with a binder resin, has good sensitivity, and can maintain predetermined sensitivity for a long time. It is an object to provide a derivative, a method for producing the same, and an electrophotographic photoreceptor.

  Surprisingly, the present inventors use an arylamine derivative having an asymmetric substituent substituted with a nitrogen atom as a charge transport material, thereby being excellent in solubility in a solvent and compatibility with a binder resin. The inventors have found that the sensitivity can be maintained over a long period of time while exhibiting good sensitivity, and the present invention has been completed.

  That is, the arylamine derivative of the present invention has the general formula (I)

(In the formula, R ^{1 to} R ¹⁵ are the same or different and each represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an optionally substituted alkoxy group, an optionally substituted aryl group, or a substituted group. An aralkyl group which may be substituted, Ar is the same or different and is an alkyl group which may be substituted, an aryl group which may be substituted or a heterocyclic group which may be substituted)
It is represented by.

  The method for producing an arylamine derivative of the present invention has the following reaction formula:

(In the formula, X is a halogen atom, and R ^{1 to} R ¹⁵ are the same or different and are a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an optionally substituted alkoxy group, or a substituted group. An aryl group that may be substituted, an aralkyl group that may be substituted, and Ar are the same or different, an alkyl group that may be substituted, an aryl group that may be substituted, or a heterocyclic group that may be substituted Is)
A process for producing an arylamine derivative represented by:
The amine derivative (11) and the halogenated aryl compound (3) are reacted, and further, the halogenated aryl compound (10) having a structure different from the halogenated aryl compound (3) is reacted.

  Further, the electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member provided with a photosensitive layer containing at least a binder resin and a charge transporting agent on a conductive substrate, wherein the charge transporting agent is the above-described general one. It contains an arylamine derivative represented by the formula (I).

  According to the arylamine derivative of the present invention and the method for producing the same, the photosensitive layer has an asymmetric substituted aryl group in the molecule as represented by the general formula (I). And the durability and solvent resistance can be improved easily and reliably.

  Moreover, according to the electrophotographic photoreceptor using such an arylamine derivative, crystallization of the charge transport material in the photoreceptor can be effectively prevented. In addition, the charge mobility can be increased, the sensitivity can be maintained, and the predetermined sensitivity can be maintained for a long time. As a result, it is possible to realize high speed and high performance of various image forming apparatuses such as copying machines and printers.

  The arylamine derivative of the present invention is represented by the general formula (I) described above.

In the general formula (I), examples of the halogen atom in R ^{1 to} R ¹⁵ include fluorine, chlorine, bromine and iodine atoms. Examples of the alkyl group include those having 1 to 6, preferably 1 to 4 carbon atoms. Specific examples include methyl, ethyl, propyl, t-butyl, n-butyl, pentyl, heptyl and the like. The alkoxy group suitably has the same number of carbon atoms as the alkyl group, and specific examples include methoxy, ethoxy, propoxy, butoxy and the like. Examples of the aryl group include those having 6 to 14 carbon atoms, preferably 6 to 10 carbon atoms. For example, a phenyl group, a naphthyl group, a biphenyl group, an anthryl group, a phenanthryl group, and the like can be given. Of these, a phenyl group is preferred. Examples of the aralkyl group include a monocyclic, polycyclic or condensed cyclic aralkyl group having 7 to 15 carbon atoms, and more specifically, for example, a benzyl group, a phenethyl group, a diphenylmethyl group, a naphthylmethyl group. And a naphthylethyl group.

In addition, the substituent may be substituted by the alkyl group, alkoxy group, aryl group, and aralkyl group in R < ¹ > -R < ¹⁵ >. Although a substituent is not specifically limited, A halogen atom, an alkyl group, an alkylene group, an alkoxy group etc. are mentioned. Examples of the alkylene group include ethylene, propylene, butylene and the like, and other than the above, the same as those described above. Moreover, although one substituent may be sufficient, 2 or more, for example, 2-5, is suitable.

In particular, R ¹ is preferably an aryl group, one, two, three or four may be substituted. Specific examples of R ¹ include

In R ² to R ¹⁵ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, more preferably a hydrogen atom, a halogen atom, a methyl group, an ethyl group are more preferable.

  Examples of the alkyl group and aryl group in Ar are the same as those described above. Examples of the heterocyclic group include those having 3 to 14 carbon atoms, preferably 4 to 10 carbon atoms. Examples of the heterocyclic group include saturated or unsaturated heterocyclic groups containing 1 to 2 nitrogen, oxygen or sulfur atoms as heteroatoms. Examples of such heterocyclic groups include pyrrolidine, piperidine, imidazoline, piperazine, furan, tetrahydrofuran, thiophene, hexahydropyrimidine, pyrrole, imidazole, oxazolepyrazine, pyrrolidinone, piperidinone, morpholine, etc. Is mentioned. Among these, as Ar, an aryl group is preferable, and a phenyl group is particularly preferable. These alkyl group, aryl group and heterocyclic group may further have a substituent. Examples of the substituent include the same substituents as exemplified above.

  The arylamine derivative of the present invention preferably has a substituent at the ortho position with respect to the phenyl group substituted with a nitrogen atom. Moreover, it is preferable that the group couple | bonded with a biphenyl group is couple | bonded with 4th-position and 4'position mutually.

  Examples of the arylamine derivative of the present invention include the compounds shown below.

  Such an arylamine derivative can be produced, for example, by the following production method.

(In the formula, X is a halogen atom, and R ^{1 to} R ¹⁵ are the same or different and are a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an optionally substituted alkoxy group, or a substituted group. An aryl group that may be substituted, an aralkyl group that may be substituted, and Ar are the same or different, an alkyl group that may be substituted, an aryl group that may be substituted, or a heterocyclic group that may be substituted Is)
That is, the halogenated aryl derivative (3) is coupled to the amine derivative (11), and the arylamine derivative (12) thus obtained has a structure different from that of the halogenated aryl compound (3). By carrying out a coupling reaction of (10), an arylamine derivative of the general formula (I) can be obtained.

  When the halogenated aryl derivative (3) is reacted with the amine derivative (11) and when the halogenated aryl derivative (10) is reacted with the obtained arylamine derivative (12), for example, the molar ratio is 1 to 5 : About 5 to 1, preferably about 1: 1. In these reactions, it is preferable to use sodium alkoxides such as sodium sodium ethoxide and sodium butoxide, metal hydrides such as sodium hydride and potassium hydride, and the like as the base. Further, it is preferable to use a catalyst such as (2-biphenyl) dicyclohexylphosphine or tris (dibenzylideneacetone) dipalladium. Although reaction time is not specifically limited, For example, about 1 to 10 hours is suitable. The reaction temperature is preferably about 80 to 180 ° C, and more preferably about 100 to 150 ° C. As the solvent used in this reaction, those which do not affect the reaction are suitable, for example, ethers such as diethyl ether, tetrahydrofuran and dioxane; halogenated hydrocarbons such as methylene chloride, chloroform and dichloroethane; Aromatic hydrocarbons such as benzene, toluene and xylene, dimethylformamide and the like.

The halogenated aryl derivative represented by (3) and the other halogenated aryl derivative represented by (10) are produced as the halogenated aryl derivative 3 and the other halogenated aryl derivative 10, respectively, by the following production method. Can do. In the following reaction formula, for ease of explanation, the halogenated aryl derivatives 10 and 3 have specific substituents R ^{2 to} R ¹⁵ and Ar, respectively, and represent specific bonds. Although represented, a compound having a substituent corresponding to the above definition can be similarly synthesized.

(Wherein X and X ′ are the same or different and are halogen atoms)
First, in order to obtain the halogenated aryl derivative 3, for example, 1,1-diphenylhydrazine hydrochloride 1 is added to a halogenated benzaldehyde 1 and reacted. In this case, the halogenated benzaldehyde 1 and 1,1-diphenylhydrazine hydrochloride 2 are preferably reacted at a molar ratio of about 1: 0.5 to 4, more preferably about 1: 1. The reaction temperature is usually about 80 to 160 ° C., and the reaction time is suitably about 1 to 10 hours. Examples of the solvent used for the reaction include the same solvents as described above.

  In addition, separately from the above reaction, first, triethyl phosphite 5 is added to a suitable solvent to react with the biphenyl compound 4 substituted with methyl halide. In this case, the halogenated methyl-substituted biphenyl compound 4 and triethyl phosphite 2 are preferably reacted at a molar ratio of about 1: 1 to 5 and further about 1: 3. The reaction temperature is usually about 80 to 160 ° C., and the reaction time is suitably about 1 to 10 hours. Examples of the solvent used for the reaction include the same solvents as described above.

  Next, benzaldehyde 7 is reacted with the obtained diphosphate derivative 6 by wittig reaction. In this case, the diphosphate ester derivative 6 and the benzaldehyde 7 are preferably reacted at a molar ratio of about 1: 1 to 3, and more preferably about 1: 1 to 2. The reaction temperature is usually about −30 to 20 ° C., and the reaction time is suitably about 5 minutes to 4 hours. As a reagent used for the wittig reaction, the above-mentioned bases can be used. Thereby, the phosphate ester derivative 8 by which the styryl group was introduce | transduced into one phosphate ester can be obtained.

  Further, in the same manner, the halogenated benzaldehyde 9 is added to the phosphate ester derivative 8 in a suitable solvent and reacted. The reaction ratio, reaction conditions, etc. in this case are exemplified as described above. Thereby, the halogenated aryl derivative 10 can be obtained.

  The electrophotographic photoreceptor of the present invention is generally constituted by forming a photoreceptor layer on a conductive substrate. The conductive substrate may be any material as long as the substrate itself has conductivity or the surface of the substrate has conductivity. For example, a metal such as iron, aluminum, copper, tin, platinum, silver, vanadium, molybdenum, chromium, cadmium, titanium, nickel, palladium, indium, stainless steel, brass, or a plastic material on which these metals are deposited or laminated, Examples thereof include a plastic material in which conductive fine particles such as carbon black are dispersed, 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, a drum shape, and the like according to the structure of the image forming apparatus to be used, but preferably has a sufficient mechanical strength in use.

  The photoreceptor layer may be a single layer type or a laminated type in which functions are separated by two or more layers. The thickness of the single-layer type photoreceptor layer is usually a value in the range of 5 to 100 μm, preferably a value in the range of 10 to 50 μm. In the multilayer type photoreceptor layer, for example, the charge generation layer is about 0.01 to 5 μm, preferably about 0.1 to 3 μm, and the charge transport layer is about 2 to 100 μm, preferably about 5 to 50 μm.

  In the electrophotographic photosensitive member, a barrier layer may be formed between the conductive substrate and the photosensitive layer as long as the characteristics of the photosensitive member are not impaired, and a protective layer is formed on the surface of the photosensitive layer. It may be.

1. Single layer type photoreceptor The photosensitive layer comprises at least an arylamine derivative of the general formula (I) as a charge transport agent (for example, a hole transport agent), a binder resin, and optionally a charge generator and / or other charge. It can be formed by dissolving or dispersing the transport agent in an appropriate solvent, coating the obtained coating solution on a conductive substrate, and drying. The single-layer type photoreceptor can be applied to both positive and negative charge types with a single configuration, has a simple layer configuration, and is excellent in productivity.

(1) Hole transport agent The electrophotographic photoreceptor of the present invention contains an arylamine derivative of the general formula (I) as a hole transport agent. This compound is as described above.

  In addition, a conventionally known hole transport agent may be used in combination. For example, N, N, N ′, N′-tetraphenylbenzidine derivative, N, N, N ′, N′-tetraphenylphenylenediamine derivative, N, N, N ′, N′-tetraphenylnaphthylenediamine derivative, N, N, N ′, N′-tetraphenylphenanthrylenediamine derivatives, oxadiazole compounds such as 2,5-di (4-methylaminophenyl) -1,3,4-oxadiazole, 9- (4-diethylaminostyryl) styryl compounds such as anthracene, carbazole compounds such as polyvinylcarbazole, organic polysilane compounds, pyrazoline compounds such as 1-phenyl-3- (p-dimethylaminophenyl) pyrazoline, hydrazone compounds, indoles Compounds, oxazole compounds, isoxazole compounds, thiazole compounds Things, thiadiazole compounds, imidazole compounds, pyrazole compounds, and nitrogen-containing cyclic compounds such as triazole compounds, and condensed polycyclic compounds. Specifically, HTM-1 to HTM-13 described in JP-A-2006-8670 and JP-A-2005-306744 can be used.

  The hole transport agent is preferably contained in an amount of 10 to 80 parts by weight with respect to 100 parts by weight of the binder resin from the viewpoint of improving sensitivity and preventing crystallization to obtain appropriate film forming characteristics. .

(2) Electron transport agent Any known electron transport agent may be used as the electron transport agent. For example, naphthalenecarboxylic acid diimide derivatives, naphthoquinone derivatives, azoquinone derivatives, diphenoquinone derivatives, benzoquinone derivatives, anthraquinone derivatives, malononitrile derivatives, thiopyran derivatives, trinitrothioxanthone derivatives, 3,4,5,7-tetranitro-9-fluorenone derivatives , Dinitroanthracene derivatives, dinitroacridine derivatives, nitroantharaquinone derivatives, dinitroanthraquinone derivatives, tetracyanoethylene, 2,4,8-trinitrothioxanthone, dinitrobenzene, dinitroanthracene, dinitroacridine, nitroanthraquinone, dinitroanthraquinone, anhydrous succinate Examples include acid, maleic anhydride, dibromomaleic anhydride and the like. These can be used alone or in combination of two or more. Specific examples include compounds represented by the following formulas (ET-1 to ET-3).

  From the viewpoint of improving sensitivity, preventing crystallization and obtaining appropriate film formability, the electron transfer agent is suitably contained in an amount of 10 to 100 parts by weight with respect to 100 parts by weight of the binder resin.

  In addition, when determining the addition amount of an electron transport agent, it is preferable to consider the addition amount of a hole transport agent mentioned above. For example, from the viewpoint of improving sensitivity, the addition ratio (total ETM / total HTM) of the electron transport agent (total ETM) is set to 0.25 to 1.3 with respect to the hole transport agent (total HTM). Is preferred.

(3) Charge generator As the charge generator, metal-free phthalocyanine (τ type or x type), titanyl phthalocyanine (α type or Y type), hydroxygallium phthalocyanine (V type), and chlorogallium phthalocyanine (II type), 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 pigments, azurenium pigments, cyanine pigments, pyrylium Organic photoconductors such as pigments, ansanthrone pigments, triphenylmethane pigments, selenium pigments, toluidine pigments, pyrazoline pigments, quinacridone pigments, selenium, selenium-tellurium, selenium-arsenic, cadmium sulfide, amorphous silicon Inorganic photoconductive agent materials such as These can be used alone or in combination of two or more. By using these compounds as charge generating agents, sensitivity characteristics, electrical characteristics, stability, and the like can be further improved when a hole transport agent and an electron transport agent are used in combination. Specific examples include phthalocyanine pigments (CGM-A to CGM-D) described in JP-A-2006-8670 and JP-A-2005-306744.

  The charge generator increases the quantum yield and also maintains the extinction coefficient for light having an absorption wavelength in the red and infrared to near-infrared regions, improving the sensitivity, electrical properties, stability, etc. of the electrophotographic photoreceptor. From the viewpoint of making it, it is appropriate to contain 0.2 to 40 parts by weight with respect to 100 parts by weight of the binder resin.

  In the case of using a charge generating agent, for example, C.I. A dispersion aid such as I Pigment Orange 16 may be added. When a dispersion aid is added, the dispersibility of the charge generating agent in the solution can be improved, and the pot life of the coating solution can be extended. In this case, it is appropriate to add 30 to 200 parts by weight with respect to 100 parts by weight of the total charge generating agent.

(4) Binder Resin The binder resin is not particularly limited as long as it is used as a binder resin in the field, and various types 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, chlorination 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 Thermoplastic resins such as resin, polyvinyl butyral resin, polyether resin, polyester resin; silicone resin, epoxy resin, phenol resin, urea resin, melamine resin, other crosslinkable thermosetting resins; epoxy acrylic Over bets, urethane - interest photocurable resin and the like such as acrylate.

(5) Additive In addition to the above-mentioned components, the photoreceptor layer has various conventionally known additives such as an antioxidant, a radical scavenger, a singlet quencher, 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 may be added. In order to improve the sensitivity of the photoreceptor layer, for example, known sensitizers such as terphenyl, halonaphthoquinones, acenaphthylene and the like may be used in combination with the charge generator.

(6) Manufacturing method The photosensitive layer is formed by a known method such as a roll mill, a ball mill, an attritor, a paint shaker, an ultrasonic disperser, etc. together with the above-described charge generator, charge transport agent, binder resin and the like in an appropriate solvent. It can be formed by preparing a dispersion liquid by dispersing the mixture using, and applying it to the surface of the conductive substrate by a known means and drying it.

  As the solvent for preparing the dispersion, various organic solvents can be used. For example, alcohols such as methanol, ethanol, isopropanol and butanol; aliphatic hydrocarbons such as n-hexane, octane and cyclohexane; benzene , Aromatic hydrocarbons such as toluene and 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, dioxane, dioxolane Ketones such as acetone, methyl ethyl ketone and cyclohexanone; esters such as ethyl acetate and methyl acetate; dimethylformaldehyde, dimethylformamide, dimethyl ester Examples include til sulfoxide. These solvents can be 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 surface of the photoreceptor layer.

2. Multilayer Photoreceptor A multilayer photosensitive layer is formed by forming a charge generation layer containing a charge generation agent on a conductive substrate by means of vapor deposition or coating, and a hole transport agent on the charge generation layer. It is produced by applying a coating solution containing a binder resin and drying it to form a charge transport layer. Alternatively, a charge transport layer may be formed on the conductive substrate, and a charge generation layer may be formed thereon. However, since the charge generation layer is much thinner than the charge transport layer, it is more preferable to form the charge transport layer on the charge generation layer for protection.

  Depending on the order in which the charge generating layer and the charge transport layer are formed and the type of the charge transport agent used in the charge transport layer, the laminate type photoreceptor is selected as a positive or negative charge type. For example, when a charge generation layer is formed on a conductive substrate and a charge transport layer is formed thereon, when a hole transport agent is used as the charge transport agent in the charge transport layer, the photoreceptor is negatively charged. Become a mold. In this case, the charge generation layer may contain an electron transport agent. By adopting the laminated type, the residual potential of the photoreceptor can be greatly reduced and the sensitivity can be improved.

  As the charge generating agent, hole transporting agent, electron transporting agent, binder resin and the like, basically the same ones as those for the single layer type photoreceptor can be used. However, in the case of a multilayer photoreceptor, the amount of charge generator added is preferably 0.5 to 150 parts by weight with respect to 100 parts by weight of the binder resin constituting the charge generation layer.

  The electrophotographic photoreceptor of the present invention can be used, for example, by the image forming apparatus shown in FIG.

  The electrophotographic photosensitive member 1 is configured by forming a photosensitive layer 11 on a support base 10, and its axis 13 is connected to a driving means 14 via a gear and a pulley in one direction (arrow A). The direction of rotation is at a constant speed.

  A main charging unit 2, an exposure unit 3, a developing unit 4, and a transfer unit 5 are provided in this order along the driving direction, that is, the rotation direction, around the photoreceptor 1.

  Further, as shown in FIG. 1, separation means 6, static elimination means 7, and cleaning means 9 may be provided as necessary.

  Further, the image forming apparatus is provided with a fixing unit 12 for fixing the toner image to the transfer medium 8 onto which the toner image has been transferred.

  When forming an image, first, the surface of the electrophotographic photosensitive member 1 is uniformly charged by the charging unit 2. Next, the surface of the electrophotographic photosensitive member 1 is exposed along the exposure axis 31 by the exposure means 3 to form an electrostatic latent image corresponding to the original image.

  Thereafter, the developing means 4 develops the toner attached to the portion corresponding to the electrostatic latent image.

  Subsequently, the toner image on the surface of the photoreceptor 1 is transferred onto the transfer medium 8 conveyed (in the direction of arrow B) by the transfer unit 5. After the transfer, the transfer medium 8 is separated from the electrophotographic photosensitive member 1 by the separating unit 6 and then toner-fixed by the fixing unit 12.

  After the transfer, the toner that cannot be transferred to the transfer medium 8 and remains on the surface of the electrophotographic photosensitive member 1 is removed by the cleaning means 9.

  Thereafter, the residual potential on the surface of the electrophotographic photosensitive member 1 is removed by the neutralizing light 71 from the neutralizing unit 7 and charged by the charging unit 2 again.

  Examples of the arylamine derivative and the electrophotographic photosensitive member of the present invention will be described below.

[Examples 1 to 4]
(Synthesis of arylamine derivatives)
First, the following reaction formula

In a 500 mL flask, compound 1 (15 g, 0.08 mol) and 1,1-diphenylhydrazine hydrochloride 2 (18 g, 0.08 mol) were weighed, and 250 ml of toluene was further added. Reacted for hours. After cooling, the resulting reaction solution was poured into ion exchange water, and the organic layer was washed three times with ion exchange water. Subsequently, the obtained organic layer was dried and adsorbed with anhydrous sodium sulfate and activated clay, and the solvent was distilled off under reduced pressure. The residue was purified by chromatography using chloroform / hexane to obtain white solid 3 (27 g, yield 95%).

  Separately from the above reaction, Compound 4 (20 g, 0.08 mol) and triethyl phosphite 5 (40 g, 0.24 mol) were weighed in a 200 mL flask and reacted at 180 ° C. for 8 hours. After cooling, excess triethyl phosphite was distilled off under reduced pressure to obtain colorless oil 6 (32.7 g, yield 90%).

  Next, the obtained oily substance 6 (15 g, 0.03 mol) was placed in a 500 mL two-necked flask at 0 ° C., purged with argon, and further 100 mL of dry THF, 28% sodium methoxide (7 0.7 g, 0.04 mol) was added and stirred for 30 minutes. Thereafter, benzaldehyde 7 (4 g, 0.04 mol) dissolved in 300 ml of dry THF was introduced and stirred at room temperature for 12 hours. The obtained reaction solution was poured into ion exchange water, extracted with toluene, and the organic layer was washed 5 times with ion exchange water. Subsequently, the obtained organic layer was dried over anhydrous sodium sulfate, and then the solvent was distilled off. The residue was purified with toluene / methanol = 20 ml / 100 ml to obtain white crystals 5 (9.8 g, yield 80%).

  Similarly, halogenated benzaldehyde 9 was reacted with compound 8 to obtain compound 10 (7.5 g, yield 71%) as a yellow solid.

  Next, the following reaction formula

Into a 2 L 2-neck flask was added compound 3 (20.0 g, 0.057
Mol), 2- (dicyclohexylphosphino) biphenyl (0.066 g, 0.19 mmol), trisdibenzylideneacetone dipalladium (0.086 g, 0.094 mmol), t-BuONa (7.68 g, 0.08). Mol), Compound 11 (8.5 g, 0.057 mol), and 500 ml of o-xylene were substituted with argon, stirred at 120 ° C. for 5 hours, and then cooled to room temperature. The organic layer in the reaction solution was washed with ion-exchanged water three times, anhydrous sodium sulfate and activated clay were added to the organic layer, dried and adsorbed, and xylene was distilled off under reduced pressure. The obtained residue was purified by column chromatography (developed with chloroform / hexane) to obtain a solid 12 (yield 20.3 g, yield 85%).

  Then, in a 300 mL two-necked flask, compound 12 (10.0 g, 0.024 mol), 2- (dicyclohexylphosphino) biphenyl (0.016 g, 0.045 mmol), trisdibenzylideneacetone dipalladium (0. 021 g, 0.023 mmol), t-BuONa (2.88 g, 0.03 mol), compound 10 (10.2 g, 0.024 mol), and 200 ml of o-xylene, substituted with argon, and heated to 120 ° C. The mixture was stirred for 3 hours and then cooled to room temperature. The organic layer in the reaction solution was washed with exchanged water three times, anhydrous sodium sulfate and activated clay were added to the organic layer, dried and adsorbed, and xylene was distilled off under reduced pressure. The obtained residue was purified by column chromatography (chloroform / hexane development) to obtain yellow crystals (yield 13.0 g, yield 70%) as compound HT-1.

(Preparation of electrophotographic photoreceptor)
60 parts by weight of the obtained arylamine derivative (compound represented by HT-1 in the above formula) as a hole transporting agent and 5% by weight of X-type metal-free phthalocyanine (CGM-A) as a charge generating agent And 100 parts by weight of Z-type polycarbonate resin as a binder resin, 0.1 part by weight of KF-96-50CS (manufactured by Shin-Etsu Chemical Co., Ltd.) which is a dimethyl silicone oil as a leveling agent, and tetrahydrofuran 800 as a solvent. Added to parts by weight. Subsequently, it was mixed and dispersed for 50 hours using a ball mill to prepare a coating solution for the photosensitive layer. The obtained coating solution is applied on a conductive base material (aluminum tube) having a diameter of 30 mm and a length of 254 mm by dip coating, and dried with hot air at 100 ° C. for 30 minutes. An electrophotographic photosensitive member having a single-layer type photosensitive layer having a thickness of 25 μm was obtained.

(Evaluation)
The initial electrical characteristics, that is, the initial surface potential (Vo), the half exposure amount (E _1/2 ), and the residual potential (Vr) of the obtained electrophotographic photosensitive member were measured.

  First, using a drum sensitivity tester (manufactured by GENTEC), the surface potential was charged to +700 V, and the initial surface potential (Vo) was measured.

Next, in the charged state, the surface of the photoreceptor is irradiated with monochromatic light (half-width: 20 nm, light intensity: 1.5 μJ / cm ² ) having a wavelength of 780 nm extracted from the light of the halogen lamp using a bandpass filter. Then, an exposure amount (half exposure amount) at which the post-exposure potential of the photoreceptor becomes 1/2 of the initial surface potential was determined. The smaller the half exposure amount, the higher the sensitivity of the photoreceptor.

  Furthermore, the surface potential at the time when 0.5 seconds passed from the start of exposure was measured, and this was defined as the residual potential (Vr). The obtained results are shown in Table 1.

[Examples 5 to 6]
In Example 2, compound HT-2 was synthesized in the same manner as in Example 1 except that 2,4,6-trimethylaniline was used instead of compound 11 in the synthesis method of Example 1 (yield) 65%), an electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Examples 1-8]
In Comparative Examples 1 to 8, the following compounds are used as the hole transport material.

An electrophotographic photosensitive member was produced and evaluated in substantially the same manner as in Example 1 except that each was used. The results are shown in Table 1.

  In the table, “x” in the initial surface potential, residual potential, and half-exposure dose indicates that evaluation could not be performed due to crystallization.

  According to Table 1, by using an arylamine derivative in which a substituent substituted with a nitrogen atom is asymmetric as a charge transport material, it has excellent solubility in a solvent and compatibility with a binder resin, and good sensitivity. , Confirmed to maintain for a long time.

  The arylamine derivative of the present invention can be used, for example, in various fields as a charge transport material that requires compatibility and sensitivity with a binder resin. In addition to maintaining the sensitivity, it can be used in various fields such as a solar cell and an electroluminescence element in addition to the electrophotographic photosensitive member of various image forming apparatuses such as a copying machine and a printer.

FIG. 2 is a schematic diagram for explaining an image forming apparatus provided with the electrophotographic photosensitive member of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrophotographic photosensitive member 2 Main charging means 3 Exposure means 4 Development means 5 Transfer means 6 Separation means 7 Electric discharge means 8 Transfer medium 9 Cleaning means 10 Support base 11 Photosensitive layer 12 Fixing means 13 Axis center 14 Driving means 31 Exposure shaft 71 Removal Lightning

Claims (3)

Formula (I)

(In the formula, R ^{1 to} R ¹⁵ are the same or different and each represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an optionally substituted alkoxy group, an optionally substituted aryl group, or a substituted group. An aralkyl group which may be substituted, Ar is the same or different and is an alkyl group which may be substituted, an aryl group which may be substituted or a heterocyclic group which may be substituted)
An arylamine derivative represented by: The following reaction formula

(In the formula, X is a halogen atom, and R ^{1 to} R ¹⁵ are the same or different and are a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an optionally substituted alkoxy group, or a substituted group. An aryl group that may be substituted, an aralkyl group that may be substituted, and Ar are the same or different, an alkyl group that may be substituted, an aryl group that may be substituted, or a heterocyclic group that may be substituted Is)
A process for producing an arylamine derivative represented by:
An aryl characterized by reacting an amine derivative (11) with a halogenated aryl compound (3) and further reacting a halogenated aryl compound (10) having a structure different from that of the halogenated aryl compound (3) A method for producing an amine derivative. An electrophotographic photosensitive member provided with a photosensitive layer containing at least a binder resin and a charge transfer agent on a conductive substrate, wherein the charge transfer agent is represented by the following general formula (I)

(In the formula, R ^{1 to} R ¹⁵ are the same or different and each represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an optionally substituted alkoxy group, an optionally substituted aryl group, or a substituted group. An aralkyl group which may be substituted, Ar is the same or different and is an alkyl group which may be substituted, an aryl group which may be substituted or a heterocyclic group which may be substituted)
An electrophotographic photoreceptor comprising an arylamine derivative represented by the formula:

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