JPH01319043A - Electrophotogfaphic sensitive body - Google Patents

Abstract

PURPOSE:To enhance photosensitivity by forming a carrier generating material made of a specified compound and a carrier transfer material made of another specified compound. CONSTITUTION:At least one of the carrier generating material is a bisazo compound represented by formula 1 and at least one of the carrier transfer material is a hydrazone derivative represented by formula 1, and in formulae I and II, each of X1 and X2 is halogen, alkyl, or the like; each of p, q, m, and n is 0, 1, and 2; Q is a group represented by formula III; Ar is an aromatic hydrocarbon group having a fluorinated hydrocarbon group or the like; Z is a nonmetallic atomic group necessary to form an aromatic hydrocarbon group or an aromatic heterocyclic group; R1 is naphthyl; R2 is alkyl, aryl, or the like; R3 is H, alkyl, or alkoxy; each of R4 and R5 is alkyl, aryl, or the like; and l is 0 or 1, thus permitting photosensitivity to be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electrophotographic photoreceptor having a photosensitive layer containing a carrier-generating substance and a carrier-transporting substance.

[Prior Art] According to a conventionally known electrophotographic photoreceptor, a carrier generating substance (hereinafter referred to as rCGMJ) that absorbs visible light and generates charge carriers (hereinafter simply referred to as "carrier") is used.
There is a thing. ) containing a carrier generation layer (
Hereinafter, it may be referred to as rcGLJ. ) and this CGL
A carrier transport layer (hereinafter sometimes referred to as rcTLJ) containing a carrier transport substance (hereinafter sometimes referred to as rCTMJ) that transports either or both of positive and negative carriers generated in Some photosensitive layers are constructed by combining them. in this way,
By assigning the two necessary basic functions of carrier generation and carrier transport to separate layers constituting the photosensitive layer, the range of materials that can be used in the composition of the photosensitive layer is widened, and each It becomes possible to independently select a material or material system that optimally performs the function.

This also provides excellent specific properties required in the electrophotographic process, such as high surface potential when charged, high charge retention capacity, high photosensitivity, and high stability during repeated use. It becomes possible to obtain an electrophotographic photoreceptor having the following properties.

As the above-mentioned photosensitive layer, for example, the following ones are known.

(1) CGL made of amorphous selenium or cadmium sulfide
and CTL made of poly-N-vinylcarbazole are laminated.

(2) CGL made of amorphous selenium or cadmium sulfide
and CTL containing 2,4.7-dolinitro-9-fluorenone are laminated.

(3) A structure in which a CGL made of a perylene derivative and a CTL containing an oxadiazole derivative are laminated (see US Pat. No. 3,871,882).

(4) CGL consisting of Chlordiayan Blue or Mesuleless Lithurium and CTL containing a pyrazoline derivative
(Refer to Japanese Unexamined Patent Publication No. 51-90827).

(5) A structure consisting of a CGL made of a bisazo compound and a CTL containing an aromatic amine compound (Unexamined Japanese Patent Publication No. 1986-
(See Publication No. 24549).

(6) A structure in which a CGL containing a perylene derivative and a CTL containing a polyarylalkane aromatic amine compound are laminated (Japanese Patent Application No. 19907-1999, Ill.
) Many functionally separated photosensitive layers are known, such as this one, but in conventional electrophotographic photoreceptors that have such photosensitive layers, the photosensitive layer when repeatedly subjected to the electrophotographic process The disadvantage is that the electrical fatigue of the layer is severe and the service life is very short.

For example, when subjected to repeated electrophotographic processes,
The potential history state of the electrophotographic photoreceptor is not maintained stably,
Stable image forming characteristics cannot be obtained.

Further, the use of specific bisazo compounds as CGM is disclosed in, for example, JP-A-55-117151 and JP-A-54.
Although it is disclosed in Publication No.-145142, etc.
Even in a rough combination with CTM, which is said to be able to be combined with M, the above-mentioned drawbacks are still considerable.

As can be understood from this, a carrier transporting substance that is effective against a particular carrier-generating substance is not necessarily effective against other carrier-generating substances, and It cannot be said that a carrier-generating substance that is effective against other carrier-transporting substances is also effective against other carrier-transporting substances. An inappropriate combination of both substances will not only lower the electrophotographic sensitivity, but also Especially in low electric fields, the discharge efficiency is poor, so the so-called residual potential becomes large.
In the worst case, potential accumulates each time it is used repeatedly, making it practically unusable for electrophotographic purposes.

In this way, it is thought that there is no legal means of selecting a suitable combination of the constituent substances of the carrier generation layer and the constituent substances of the carrier transport layer, and an advantageous combination is determined practically from among many substance groups. There is a need to.

Furthermore, in recent years Ar laser and He-N have been used as light sources for photoreceptors.
Gas lasers such as e-lasers and semiconductor lasers are beginning to be used. These lasers are characterized by being capable of 0N10FF in time series, and are particularly promising as a light source for copying machines and computer output printers with image processing functions, such as intelligent copiers. Among these, semiconductor lasers are attracting attention because their nature does not require electrical signal/optical signal conversion elements such as acoustic engineering elements, and they can be made smaller and lighter. However, this semiconductor laser has a low output compared to a gas laser, and the emitted wave has a long wavelength (approximately 78<lnm or more), so the spectral sensitivity of conventional photoreceptors is often on the short wavelength side. However, there were no practically satisfactory sensitivity characteristics.

[Object of the Invention] Accordingly, an object of the present invention is to provide an electrophotographic photoreceptor that is highly sensitive, has a small residual potential, and has excellent durability with little change in its characteristics even after repeated use.

Another object of the present invention is to provide an electrophotographic photoreceptor that has sufficient practical sensitivity even to long wavelength light sources such as semiconductor lasers.

[Means for Solving the Problems 1] As a result of intensive research to achieve the above object, the present inventors have developed a carrier-generating substance of a specific bisazo compound and carrier transport of a specific hydrazone compound in the photosensitive layer. The present inventors have discovered that an electrophotographic photoreceptor containing a substance and in which at least the uppermost layer of the photosensitive layer contains a specific polycarbonate as a main component of the binder can achieve all of the above objects, and have completed the present invention. .

That is, the object of the present invention is to provide an electrophotographic photoreceptor having a photosensitive layer containing a carrier-generating substance and a carrier-transporting substance on a conductive support, in which at least one of the carrier-generating substances is This can be achieved by an electrophotographic photoreceptor comprising a bisazo compound represented by [I], and at least one of the carrier transport substances comprising a hydrazone compound represented by the following general formula [II]. can.

General formula [I] υ [×1 and It represents an amino group, and at least one of x1 and x2 is a halogen atom.

p and q each represent an integer of 0.1 or 2, p and q are never 0 at the same time, and p and q are 2
In this case, x1 and x2 may be the same or different groups, respectively. Q represents a group represented by the following general formula.

Z' (wherein, Ar represents an aromatic carbocyclic group having a fluorinated hydrocarbon group or an aromatic heterocyclic group having a fluorinated hydrocarbon gAl); Z is a substituted or unsubstituted aromatic carbocyclic group; or a nonmetallic atomic group necessary to form a substituted or unsubstituted aromatic heterocycle), ffl and n each represent an integer of 0.1 or 2. However, n and n cannot be 0 at the same time, 1 General formula [111 [wherein R1 represents a substituted or unsubstituted naphthyl group, R2 represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted naphthyl group] It represents an aryl group or a substituted or unsubstituted aralkyl group, and R3 represents a hydrogen atom, an alkyl group, or an alkoxy group. R4 and R5 represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group. However, 2 is an integer of O or 1. ] [Specific Structure of the Invention] Examples of the halogen atom represented by x1 and x2 in general formula [I] include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.

In the bisazo compound of the present invention, at least one of ×1 and ×2 has a halogen atom.

The alkyl group represented by x1 and x2 is preferably a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and examples of such alkyl groups include methyl group, ethyl group, β-cyanoethyl group, etc. group, 1so-propyl group, trifluoromethyl group, (-butyl group, etc.).

The alkoxy group represented by x1 and x2 is preferably a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms, and examples of such alkoxy groups include methoxy group, ethoxy group, β- Chlorethoxy group, 5
Examples include ec-butoxy group.

Furthermore, the substituted or unsubstituted amino groups represented by x1 and x2 include those substituted with, for example, alkyl groups, aryl groups (preferably phenyl groups), etc. Amino group, N, N-
Examples include a dimethylamino group, an N,N-diethylamino group, an N-phenylamino group, an N,N-diphenylamino group, an acetylamino group substituted with an acyl group, a p-chlorobenzoylamino group, and the like.

In the general formula [I], p and q each represent 0.
1 or 2, but p and q are never O at the same time, preferably p-1, q=0 or I)-1, Q-
This is the case of 1.

Furthermore, when p and q are 2, xl and x2 are
They can each have the same or different groups.

Moreover, in the general formula [I], Q is represented by the following -Sakatsu.

ゝ゛Z' In the formula, Ar represents an aromatic carbocyclic group or an aromatic heterocyclic group having at least one fluorinated hydrocarbon N'S, but fluorine having 1 to 4 carbon atoms in the fluorinated hydrocarbon group Hydrocarbon groups are preferred, such as trifluoromethyl, pentafluoroethyl, tetrafluoroethyl, heptafluoropropyl and the like. Among these, a more preferred fluorinated hydrocarbon group is a trifluoromethyl group. Further, examples of the aromatic IM carbocyclic group include phenyl group, naphthyl group, anthryl group, etc.
Preferably it is a phenyl group. Further said aromatic? Examples of the I ring group include a carbazolyl group and a dibenzofuryl group. Furthermore, in the aromatic carbocyclic group and the aromatic heterocyclic group, the fluorinated hydrocarbon
Substituents other than l include, for example, substituted and unsubstituted alkyl groups having 1 to 4 ft4 carbon atoms, such as methyl, ethyl, isopropyl, (-butyl, trifluoromethyl, etc.); Unsubstituted aralkyl groups, such as benzyl group, phenethyl group, etc.; Halogen atoms, such as chlorine atom, bromine atom, fluorine atom, iodine atom; Substituted or unsubstituted alkoxy groups having 1 to 4 carbon atoms, such as methoxy group; Ethoxy group, isobutoxy group, t-
-xy group, 2-chloroethoxy group, etc.: hydroxy group; substituted or unsubstituted aryloxy group, such as p-
Niacyloxy groups such as chlorphenoxy group and 1-naphthoxy group, such as acetyloxy group and p-cyanobenzoyloxy group; Carboxyl group and its ester group, such as ethoxycarbonyl group and 1-bromophenoxycarbonyl group; Carbamoyl group, such as amino carbonyl group, t
-Butylaminocarbonyl group, anilinocarbonyl group, etc.; Acyl group, such as acetyl group, O-nitrobenzoyl group, etc.: Sulfo group, sulfamoyl group, such as aminesulfonyl group, t-butylaminosulfonyl group, p-tolylaminosulfonyl group etc.; Amim L Acyl Amim L, such as acetylamim L, benzoylamino group, etc.: Sulfonamide group, such as methanesulfonamide group, p-toluenesulfonamide group, etc.; Cyano 3! ! : Nitro group etc. Among these substituents, preferred are substituted or unsubstituted alkyl groups having 1 to 411 m carbon atoms, such as methyl group, ethyl group, isopropyl group, °C-butyl group, trifluoromethyl group, etc.; halogen atoms, e.g. Chlorine atom, bromine atom, fluorine atom, iodine atom: carbon atom @1
Or 4! i-substituted/unsubstituted alkoxy groups, such as methoxy group, ethoxy group, (-7 toxy group, 2-chloroethoxy group, etc.; nitro group; cyano group, etc.).

In the above-mentioned -Sakatsu, Z is an atomic group necessary to form a substituted/unsubstituted aromatic carbocycle or a substituted/unsubstituted aromatic heterocycle, and specifically, for example, substituted/unsubstituted benzene. V represents an atomic group necessary to form a ring, a substituted/unsubstituted naphthalene ring, a substituted/unsubstituted indole ring, a substituted/unsubstituted carbazole ring, etc.

Atoms l needed to form these rings! Examples of the substituent for f include a series of substituents such as those listed as substituents for Ar, but preferably a halogen atom (chlorine atom, bromine atom, fluorine atom, iodine atom), a sulfo group, a sulfamoyl group (For example, aminosulfonyl m, p-tolylaminesulfonyl group, etc.).

The bisazo compound represented by the above-mentioned -killing [I] of the present invention is preferably the following - killing [II], [rV], [V]
, [VI].

-Salty [111] % formula % ( -Salty [IV] Y -CONHAr' General formula [V] General formula [V!] In the formula, X + a , X 1t1. X 21 and X
2b represents a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a nitro group, a cyano group, a hydroxy group, or a substituted or unsubstituted amino group, X 1a, , X
+b At least one of +X2a and X2b is a halogen atom. xlcL and X+i), and X2 (L and X2b may each be the same or different groups.

Ar' is synonymous with A' in the above-mentioned -slaughter [I'l].

Y has the same meaning as the substituent of Z in the above-mentioned -Sakuhatsu [I].

Specific examples of the bisazo compound represented by the above-mentioned -killing [I] of the present invention will be described below, but the bisazo compound of the present invention is not limited thereto.

□・″−=” From then on, margin To.

The bisazo compound represented by the above-mentioned -killing [I] of the present invention can be easily synthesized by a known method.

Synthesis Example 1 (Synthesis of Exemplified Compound No. 71) 2.7-Diami2-4-bromo-9-fluorenone 2.89N O,
01 mol) was dispersed in 10n12 of hydrochloric acid and 20112 of water,
1 to 1.40 g (0
, 02 mol) dissolved in 5 cups of water was added dropwise. After continuing stirring at the same temperature for an additional hour, insoluble materials were removed by filtration, and a solution of 4.6 g of ammonium hexafluorophosphate dissolved in 50 d of water was added to the filtrate. The precipitated tetrazonium salt was collected by filtration, and N,N-dimethylformamide (DMF) 1
Dissolved in 00 years old. A solution of 6.62 g (0.02 mol) of 2-hydroxy-3-naphthoic acid-3'-trifluoromethylanilide dissolved in DMFZQO was added dropwise while maintaining the temperature at 5° C. or lower.

Subsequently, while keeping the temperature below 5°C, a solution of triethanolamine fl (0.04 mol) in 301 fl of DMF was added dropwise, followed by stirring at below 5°C for 1 hour and at room temperature for 4 hours. After the reaction, the precipitate was collected by filtration, washed with DMF, washed with water, and dried to obtain the desired product 8.11.

Theoretical values C-60.5%, H-2.77%, N-8.63% Actual values C-60.1%, H-2.95%, N-8.72% Synthesis Example 2 (Exemplary Compound Synthesis of No. 219) 2.89 g (0
,01'F Nil> @211110xQ, dispersed in water 20-, and added sodium nitrite 1.40 (
A solution of 1 (0.02 mol) dissolved in 5112 ml of water was added dropwise. After continuing stirring at the same temperature for another hour, insoluble matter was removed by filtration, and a solution of 4.69 g of ammonium hexafluorophosphate dissolved in 50 g of water was added to the filtrate. The precipitated tetrazonium salt was collected by filtration and treated with N,N-dimethylformamide (DM
F) 100. Dissolved in Q. While keeping the temperature below 5℃,
-Hydroxy-3-(3'-trifluoromethylphenylcarbamoyl)benzo[a]carbazole 8.4
A solution of 0g (0.02 mol) dissolved in 0MF200 was added dropwise.

Subsequently, while keeping the temperature below 5°C, a solution of triethanolamine 6Q (0.04 mol) in DMF 30 *Q was added dropwise, followed by stirring at below 5°C for 1 hour and at room temperature for 4 hours. After the reaction, the precipitate was collected by filtration, washed with DMF, washed with water, and dried to obtain 5.2 g of the target product.

Theoretical value C = 63.6%, H = 2.87%, N - 9,73% Actual value C - 63,4%, H = 2.97%, N = 10.01
% For other compounds of the present invention, diazonium salts were prepared using the corresponding amino compounds in the same manner as in Synthesis Example 1, and
It can then be produced by reacting with 2-hydroxy-3-naphthoic acid-substituted anilide or 2-hydroxy-3-(substituted phenylcarbamoyl)benzo[al-U substituted/unsubstituted carbazole.

A hydrazone compound represented by the general formula [II] (hereinafter sometimes referred to as a hydrazone compound according to the present invention).

), examples of the alkyl group in R2, R3, R4 and R5 include methyl group, ethyl group, propyl group, butyl group, etc., and examples of the aryl group in R2, R4 and R5 include phenyl group, naphthyl group, etc. Examples of the aralkyl group in R2, R4 and R5 include benzyl group, phenethyl group, naphthylmethyl group, etc., and examples of the alkoxy group in R3 include methoxy group, ethoxy group, butoxy group, etc. It will be done. Also, R+.

Examples of atoms or groups that can be substituted for R2, R4 and R5 include alkyl groups, alkoxy groups, halogen atoms, and dialkylamino groups. Furthermore, two of R4 and R5 may be linked to each other to form a ring.

Specific examples of the compound represented by the general formula [I] are described below, but the hydrazone compound according to the present invention is not limited thereto.

below! The hydrazone compounds according to the present invention as described above are disclosed in, for example, JP-A-57-101844 and JP-A-57-2.
Those skilled in the art can easily synthesize it by referring to the method described in Publication No. 04549 and the like.

The bisazo compound of the present invention has excellent photoconductivity, and the electrophotographic photoreceptor of the present invention can be produced by providing a photosensitive layer in which the bisazo compound is dispersed in a binder on a conductive support. The bisazo compound of the present invention is used as a carrier-generating substance by utilizing its excellent carrier-generating ability, and a carrier-transporting substance consisting of the hydrazone compound of the present invention that can effectively act in combination with the bisazo compound is used. By doing so, it is possible to obtain a so-called functionally separated photoreceptor. The functional separation type photoreceptor may be a mixed and dispersed type of both of the above materials, but it may be composed of a carrier generation layer containing a carrier generation substance made of the bisazo compound of the present invention and a hydrazone compound according to the present invention. It is more preferable to use a laminated type photoreceptor in which a carrier transport layer containing a carrier transport substance is laminated.

In the electrophotographic photoreceptor of the present invention, for example, as shown in FIG. and a carrier-generating layer 2 containing a binder resin if necessary as a lower layer, and a carrier transporting substance made of a hydrazone compound according to the present invention and a carrier-generating layer 2 containing a binder resin according to the present invention and the general formula [A
] A photosensitive layer 4 having a functionally separated multilayer FIJ structure and having a carrier transport layer 3 containing polycarbonate as the main component of the binder resin as an upper layer, is provided on a support 1 as shown in FIG. 8I, which has a carrier transport layer 3 containing the hydrazone compound according to the present invention as a lower layer and a carrier generation Fm2 containing the bisazo compound of the present invention as an upper layer.
A photosensitive layer 4 having a layered structure is provided, and as shown in FIG. 3, a carrier generating material comprising a bisazo compound of the present invention, a carrier transporting material comprising a hydrazone compound according to the present invention, and a binder resin are provided on a support 1 as shown in FIG. Examples include those provided with a photosensitive layer 14 having a single layer structure containing .

Further, the carrier generation layer may contain both a carrier generation substance made of the bisazo compound of the present invention and a part of the carrier transport substance made of the hydrazone compound according to the present invention. In any of the layer configurations, Figures 7 to 9
Place itl on top of the photosensitive layer as shown in the figure! Further, as shown in FIGS. 4 to 6, a sublayer II (intermediate layer) having a barrier function and adhesive property may be provided between the support and the photosensitive layer.

In the case of forming a photosensitive layer having a two-layer structure, the carrier generation layer can be provided by the following method.

(a) A method of applying a solution prepared by dissolving the carrier-generating substance comprising the bisazo compound of the present invention in a suitable solvent, or a solution obtained by adding a binder to the solution and mixing and dissolving the same.

(1) A method in which the carrier-generating substance comprising the bisazo compound of the present invention is made into fine particles in a dispersion medium using a ball mill, a homomixer, etc., and a binder is added as necessary to mix and disperse the obtained dispersion, and the resulting dispersion is applied.

Dispersing the particles under the action of ultrasound in these methods allows for homogeneous dispersion.

Examples of the solvent or dispersion medium used for forming the carrier generation layer include n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethanolamine, N,N-dimethylformamide, acetone, methyl ethyl ketone, cyclohexanone, Examples include benzene, toluene, xylene, chloroform, 1,2-dichloroethane, dichloromethane, tetrahydrofuran, dioxane, methanol, ethanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, and the like.

Any binder can be used as the binder for the photosensitive layer, but a high molecular weight polymer that is hydrophobic, has a high dielectric constant, and has the ability to form an electrically insulating film is particularly preferred. Examples of such polymers include, but are not limited to, the following:

a) Polycarbonate 1 b) Polyester C) Methacrylic resin d) Acrylic resin e) Polyvinyl chloride f) Polyvinylidene chloride 9) Polystyrene h) Polyvinyl acetate i) Styrene-butadiene copolymer j) Vinylidene chloride-acrylonitrile copolymer Coalescence k) Vinyl chloride-vinyl acetate copolymer 1) Vinyl chloride-vinyl acetate-maleic anhydride copolymer m) Silicone resin n) Silicone-alkyd resin O) Phenol-formaldehyde resin p) Styrene-
Alkyd resin q) Poly-N-vinylcarbazole r) Polyvinyl butyral In the electrophotographic photoreceptor of the present invention, in order to further improve characteristics such as charging performance, repeatability, and printing durability,
At least as the main binder component of the uppermost layer of the photosensitive layer, polycarbonate 1 represented by the following formula (A) is used.

-Slaughter (A> In the formula, R11, R11, R+5, R+6, R1
? , RI8゜R19, R20 each represent a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic group, or a substituted or unsubstituted carbocyclic group, and n' is 10 to 1
It is 000.

2 represents an atomic group necessary to form a W1-substituted or unsubstituted carbocycle or a substituted or unsubstituted heterocycle.

The uppermost layer here means, for example, when the photosensitive layer is composed of two layers, a carrier generation layer and a carrier transport layer, the uppermost layer of these 2H is the carrier generation layer or the carrier transport layer. .

For example, in the case of a single-layer photosensitive layer containing a carrier-generating substance and a carrier-transporting substance as shown in FIG.
This photosensitive layer is the top layer. Furthermore, as shown in FIGS. 7 to 9, when there is a protective layer on the photosensitive layer, this protection! The L layer may contain a polycarbonate resin represented by the general formula [A] of the present invention as a main binder component. The main component of the binder in the uppermost layer means that the binder contained in the uppermost layer contains at least 50 wt% of polycarbonate represented by the general formula [A] of the present invention.

In the present invention, at least 5 wt % of the binder in the uppermost layer of the photosensitive layer is polycarbonate represented by the above-mentioned -Kaburi [A]! As the binder component of the layers other than the uppermost layer, the above-mentioned high molecular weight polymers can be used alone or in combination. in this case,
The polycarbonate represented by the general formula [A] of the present invention may be used as the main component of the binder. Furthermore, a binder component other than the polycarbonate of the present invention may be used as the main component.

Specific examples of the polycarbonate represented by the above-mentioned -Sakatsu (A) include the following.

In addition, in the present invention, environmental resistance, particularly charging characteristics due to the generation of active substances such as ozone during charging due to corona discharge in the electrophotographic process, is required. In order to prevent a decrease in sensitivity and an increase in residual potential, it is preferable to add an antioxidant to the photosensitive layer. As such an antioxidant, a compound having a hindered phenol structural unit is preferably used.

The hindered phenol structural unit referred to in the present invention is a phenolic structural unit characterized by the presence of a bulky atomic group at the ortho position of a phenolic hydroxyl group.

Branched alkyl groups are generally advantageous as bulky atomic groups.

The mechanism of its action and effect is not clear, but it is thought to be due to the steric hindrance created by the bulky atomic group, which suppresses the thermal vibration of the phenolic hydroxyl group or alkoxy group or prevents the influence of external active substances.

In the present invention, the compounds having a hindered phenol structural unit include the following formula [■ or -a [rX]
The one represented by is preferable.

- Killing [■] In the formula, R21 and R22 are each a substituted or unsubstituted argyl group, and at least one of them is a branched alkyl group.

R23, R2 and R25 are each a hydrogen atom, a hydroxy group, a substituted or unsubstituted alkyl group, or 'a
Represents a substituted or unsubstituted aryl group, R23 and R2+
Alternatively, R24 and R25 may be mutually connected to form a ring.

At least one of R21 and R22 has 3 to 4 carbon atoms.
Preference is given to zero jet- or 5ec-alkyl groups.

R2+, R22, R23, R24 and R25 are substituted or unsubstituted [yj4 is an alkyl group having 1 to 1 carbon atoms]
40 is preferred, and examples of the substituted or unsubstituted aryl group include phenyl group, naphthyl group, and pyridyl group.

An example of a ring formed by connecting R23 and R24 or R24 and R25 with each other is an O-man ring.

General formula [rX] In the formula, R31 and R32 each represent a substituted or unsubstituted alkyl group, and ■ represents an oxygen atom or an imino group. X does not represent a carbon atom, a sulfur atom, an octadecyl group, or a 100820H20- group.

22 represents an integer of 1 or 2, +2 represents an integer of 0.1.2 or 3, and 2 represents an integer of 1.2 or 4.

Next, a compound having a hindered phenol structural unit used in the present invention (hereinafter referred to as the HP compound of the present invention)
Typical examples are shown below, but the invention is not limited to these.

Exemplary compounds having hindered phenol structural units - Compounds represented by the shell formula [■J HP-1 HP-2 HP-3 HP-40 (,,?iri CI(.

HP-5 ) (P-6 HP-7 HP-8 HP-9 HP-10 HP-11 υH The following margins are examples of compounds represented by the general formula [IXl P-34 P-35 P-36 1 (P-37 P-38) iP-39 P-40 Below margin These compounds are commercially available products (e.g. Irganox manufactured by Ciba Geigy) that are available as antioxidants for plastics, synthetic fibers, elastomers, waxes, oils and fats, etc.
and also 3-(4-humanOxy3.5-dit-
It can be synthesized from (butylphenyl)buOpionic acid or 4-hydroxy-3,5-di-t-butylphenyl acetic acid and a polyol or polyamine.

In the present invention, the following antioxidants can be used in addition to the compound having the hindered phenol structural unit.

Paraphenylenediamines N-phenyl-N'-isopropyl-p-phenylenediamine, N,N'-di5ec-butyl-p-phenylenediamine, N-phenyl-N-5eC-butyl-p-
Phenylenediamine, N+N'-Shiitubu O Pill p-
phenylenediamine, N,N'-dimethyl-N,N'-
di-t-butyl-p-phenylenediamine and the like.

Hydroquinones 2.5-di-t-octylhydroquinone, 2゜6-sidedecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t-
Octyl-5-methylhydroquinone, 2-(2-octadecenyl)-5-methylhydroquinone, etc.

Organic sulfur compounds dilauryl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, ditetradecyl-3,3'-thiodipropionate, etc.

Organic phosphorus compounds triphenylphosphine, tri(nonylphenyl)phosphine, tri(dinonylphenyl)phosphine, tricresylphosphine, tri(2,4-dibutylphenoxy)phosphine, etc.

These compounds are known as antioxidants for rubber, plastics, oils and fats, and are easily available commercially.

These antioxidants may be added to any of the carrier generation layer, carrier transport layer, or protective layer, but are preferably added to the carrier transport layer.

In that case, the amount of the antioxidant added is 0.1 to 100 parts by weight, preferably 1 to 50 parts by weight, based on 100 parts by weight of the carrier transport material containing the hydrazone compound according to the present invention.
Particularly preferred is 5 to 25 parts.

Next, the conductive support supporting the photosensitive layer is a metal plate made of aluminum, nickel, etc., a metal drum or metal foil, a plastic film deposited with aluminum, tin oxide, indium oxide, etc., or paper coated with a conductive substance. , a film or drum of plastic or the like can be used.

In the present invention, the carrier generation layer is typically formed by applying a dispersion of the bisazo compound of the present invention described above in a suitable dispersion medium or solvent alone or together with a suitable binder resin, for example, by dip coating, spray coating, blade coating, etc. It can be provided by a method of coating on the support or subbing layer or carrier transport layer by roll coating or the like and drying it.

The bisazo compound of the present invention is made into fine particles of an appropriate particle size using, for example, a ball mill or a sand mill.
It can be dispersed in a dispersion medium.

A ball mill, homomixer, sand mill, ultrasonic disperser, attritor, etc. are used for dispersing the bisazo compound of the present invention.

When the photoreceptor of the present invention has a laminated structure, the binder in the carrier generation layer, the carrier generation substance made of the bisazo compound of the present invention, and the carrier transport substance made of a dracine-based compound according to the present invention have a weight ratio of O to 100: 1~50
0: O~500.

If the content of the carrier-generating substance is less than this, the photosensitivity will be low and the residual potential will increase, and if it is more than this, the dark decay and acceptance potential will decrease.

The thickness of the carrier generation layer formed as described above is
Preferably 0.01 to 10μ, particularly preferably 0.1
~5μ ugly.

Further, the carrier transport layer may be formed by dissolving and dispersing the carrier transport substance made of the hydrazone compound according to the present invention in a suitable solvent or dispersion medium alone or together with the above-mentioned binder resin, and then coating and drying. I can do it.

As the dispersion medium used, the dispersion medium used in dispersing the carrier-generating substance can be used.

The carrier transport substance made of a hydrazone compound according to the present invention can be used alone or in combination of two or more. Further, as long as it does not contradict the purpose of the present invention, it may be used in combination with other carrier transport substances other than the hydrazone compound according to the present invention.

Carrier transport substances that can be used in the present invention include:
Although not particularly limited, examples include aromatic amine compounds, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidasilone derivatives, imidazo 19
211 compound, bisimidazolidine derivative, styryl compound, hydrazone compound, pyrazoline derivative, amine derivative, oxacilone derivative, benzothiazole derivative, benzimidazole derivative, quinazoline derivative, benzofuran derivative, acridine derivative, phenazine derivative, poly-N-vinylcarbazole, poly-1-vinylpyrene,
Poly-9-nylanthracene and the like.

The carrier transport material of the present invention in the carrier transport layer is preferably 20 to 200 parts by weight, particularly preferably 30 to 150 parts by weight, per 100 parts by weight of the binder resin.

The thickness of the carrier transport layer to be formed is preferably 5 to 5.
0 μm, particularly preferably 5 to 30 uI11.

Moreover, single F! containing the bisazo compound of the present invention and the hydrazone compound according to the present invention! Binder in the case of li functionally separated electrophotographic photoreceptor = bisazo compound of the present invention:
The ratio of the hydrazone compound according to the present invention is 0 to 1008
1 to 500: O to 500 is preferred, and the thickness of the photosensitive layer to be formed is preferably 5 to 50 μl, particularly preferably 5 to 30 μl.

In the present invention, the carrier generation layer may contain one or more electron-accepting substances for the purpose of improving sensitivity, reducing residual potential or fatigue during repeated use, etc.

Examples of electron-accepting substances that can be used here include succinic anhydride, maleic anhydride, dibromaleic anhydride, phthalic anhydride, tetrachlorophthalic anhydride,
Tetrabromo phthalic anhydride, 3-nitro phthalic anhydride,
4-nitrophthalic anhydride, pyromellitic anhydride, mellitic anhydride, tetracyanoethylene, tetracyanoquinodimethane, O-dinitrobenzene, 1-dinitrobenzene, 1°3.5-trinido-Obenzene, varanitrobenzonitrile , vicryl chloride, quinone chlorimide,
Chloranil, pullmanil, dichloro-O dicyanobara benzoquinone, anthraquinone, dinitroanthraquinone, 2
．． 7-dinitrofluorenone, 2,4.7-dolinitrofluorenone, 2゜4.5.7-tetranitrofluorenone, 9-fluorenylidene [dicyanomethylenemalonodinitrile 1, polynitro-9-fluorenylidene]
Dicyanomethylene malonodinitrile, picric acid, 0
-Nitrobenzoic acid, p-nitrobenzoic acid, 3゜5-dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3.5-dinitrosalicylic acid, phthalic acid, mellitic acid, compounds with high electron affinity can be mentioned.

Further, the addition ratio of the electron-accepting substance is the bisazo compound of the present invention:'Ia electron-accepting substance-00:04
01-200, preferably 100: 0.1-100
It is.

This electron-accepting substance may be added to the carrier transport layer. The addition ratio of the electron-accepting substance to this layer is based on the weight ratio of the total carrier-transporting substance containing the carrier-transporting substance of the present invention: 1
! Child receptivity Monoga-100: 0.01-100, preferably 100: 0.1-50.

In addition, the photoreceptor of the present invention may also contain, if necessary, an ultraviolet absorber, an antioxidant, etc. for the purpose of protecting the photosensitive layer, and may also contain a dye for color sensitivity correction.

The electrophotographic photoreceptor of the present invention can be sensitive to visible light and near-infrared light.

Examples of light sources with such wavelengths include halogen lamps,
Fluorescent lamps, tungsten lamps, gas lasers such as argon lasers, helium-neon lasers, semiconductor lasers, and the like are used.

According to the present invention, the bisazo compound represented by the general formula [11] is used as a CGM, and the bisazo compound represented by the general formula [1 []
Using the hydrazone compound shown as CTM,
By skillfully combining these and preferably using polycarbonate represented by the general formula (A>) as a binder, it is possible to obtain extremely high sensitivity, large charge retention, and extremely low residual potential, making it stable even after repeated use. An electrophotographic photoreceptor that exhibits high performance and does not accumulate charge can be produced.Furthermore, the electrophotographic photoreceptor of the present invention exhibits good sensitivity to long wavelength light and laser light, making it highly reliable. It can also be used in laser printers that use semiconductor laser light sources, which are expected to have high performance.

[Examples] Hereinafter, the present invention will be specifically explained using Examples, but the embodiments of the present invention are not limited thereby.

Example 1 Vinyl chloride-vinyl acetate-
'Maleic anhydride copolymer "S-LEC MF-10J"
(manufactured by Block Chemical Co., Ltd.) with a thickness of 0.05 μm was provided, and on top of that, 2 g of Exemplified Compound No. 71 and 2 g of polycarbonate resin “Panlite-12504 (manufactured by Yojin Kasei Co., Ltd.) were added. It was added to 2-dichloroethane 1101Q and dispersed in a ball mill for 12 hours. This dispersion was coated to a film thickness of 0.5 μm when dried to form a carrier generation layer, and an exemplary compound was added as a carrier transport substance on top of this. The hydrazone compound 69 shown in IF-2 was added to the polycarbonate resin “Nipilon Z-200J (exemplary compound (
A-2)) (manufactured by Mitsubishi Gas Chemical Co., Ltd.) 10o and 1.
A photoreceptor of the present invention was prepared by coating a solution dissolved in 80% of 2-dichloroethane so that the film thickness after drying was 15 μm to form a carrier transport layer. This will be referred to as "Sample 1".

Examples 2 to 5 Four types of CTLs were prepared in the same manner as in Example 1 except that Exemplary Compounds I [-6, IF-13, ■-22, and I-8 were used as hydrazone compounds, respectively. A light absorbing body of the present invention was created. These will be referred to as "Sample 2,""Sample3,""Sample4," and "Sample 5," respectively.

Examples 6 and 7 In the formation of CGL, Exemplary Compounds 37 and 72 were used as CGM, and polycarbonate resin GL [Nipilon Z-200J (manufactured by Mitsubishi Gas Chemical Co., Ltd.) was used as a binder, and in the formation of CTL, CTM
Two types of electrophotographic photoreceptors of the present invention were prepared in the same manner as in Example 1, except that exemplified compounds IF-2 and I-6 were used as exemplified compounds. These will be referred to as "Sample 6" and "Sample 7."

Example 8 An intermediate layer was provided on a conductive support in the same manner as in Example 1, and 2 g of Exemplified Compound 71 and the general formula (
A) Polycarbonate resin “Nipilon Z-
200J (Exemplary Compound (A-2)) (Mitsubishi Gas Chemical Co., Ltd.) 19 and 1°2-dichloroethane 100-1
In addition to No. 12, the mixture was dispersed in a ball mill for 12 hours, and the resulting dispersion was applied onto the intermediate layer using a doctor blade and sufficiently dried to form a CGL with a thickness of about 0.5 μm.

On this CGL, 6 g of exemplified compound ■-2 was added as CTM.
and the following antioxidant (AO-1>0.6 (1 is a polycarbonate resin r-L-F represented by the general formula (A):
'ONZ-200J (Exemplary Compound (A-2)'J (manufactured by Mitsubishi Gas Chemical Co., Ltd.) 10g was dissolved in 1,2-dichloroethane 801Q so that the film thickness after drying was 15μ-. A photoreceptor of the present invention was prepared by coating to form a CTL.This will be referred to as sample 8.

:'- The following margin antioxidant (AO-1) Examples 9 to 11 In the formation of CGL in Example 1, Exemplary Compound No. 7
In place of 1, exemplified compounds NO, 219, 220 and 21
1, respectively, and also in the formation of CTL, Exemplary Compound I
[In place of -2, exemplified compounds ll-2, -13 and I
Three types of electrophotographic photoreceptors of the present invention were prepared in the same manner as in Example 1 except that [-31 was used. These photoreceptors are referred to as "Samples 9.1o and 11."

Example 12 Vinyl chloride-vinyl acetate-
Maleic anhydride copolymer “S-LEC MF-10J
(manufactured by Blockchain Chemical Co., Ltd.) with a thickness of 0.05 μm, and on top of that an intermediate layer consisting of Exemplary Compound I [
-3460 and a polycarbonate resin represented by the general formula <A
) in 80 nN of 1,2-dichloroethane was applied so that the film thickness after drying was 15 μm.
A carrier transport layer was formed.

Furthermore, on top of that, Exemplified Compound No. 71 2a and the following antioxidant AO-2 were added at 0.2 (1), polycarbonate resin [Nipiron Z-200J (Exemplified Compound (A-2) > 2 (
l and 1.2-dichloroethane 70v (l and 1.1.2
- In addition to 30 d of trichloroethane, a solution dispersed in a ball mill for 24 hours was applied, and a carrier generation layer having a thickness of 4 μm after drying was provided to prepare a photoreceptor of the present invention. This photoreceptor will be referred to as sample 12.

AO-2 Comparative Example 1 In the formation of CGL in Example 1, a compound having the following structure (
A comparative electrophotographic photoreceptor was manufactured in the same manner as in Example 1 except that CG-1) was used.

This is referred to as "comparative sample 1."

(CG-1) Comparative Example 2 In the formation of CGL in Example 1, a compound having the following structure (
A comparative electrophotographic photoreceptor was produced in the same manner as in Example 1, except that CG-2) was used.

This will be referred to as "comparative sample 2."

(CG-2> Comparative Example 3 In the formation of CGL in Example 1, N,N'-dimethyl-perylene-3,4,9,1 was used instead of CGM of the present invention.
Using 0-tetracarboxylic acid diimide (CG-3), C
Comparative electrophotographic photoreceptors were prepared in the same manner as in Example 1, except that the exemplified compound If-6 of the present invention was used in forming the TL. This will be referred to as "comparative sample 3."

Comparative Example 4 In the formation of CG+- in Example 1, a compound other than the present invention having the following groove structure (CG-4) was used instead of the CGM of the present invention.
Comparative electrophotographic photoreceptors were prepared in the same manner as in Example 1, except that Exemplary Compound (1)-13 of the present invention was used in the formation of CTL. This is called “Comparative Sample 4”.
”.

（CG-4） In the same manner as in Example 1, except that Exemplified Compound 72 was used instead, and in the formation of CTL, triphenylamine (CTM (1)) outside the present invention was used instead of Exemplified Compound 1f-2. Comparative sample 5 was prepared.

For each of the electrophotographic photoreceptors (Samples 1 to 12 and Comparative Samples 1 to 5) obtained as described above, an electrometer EPA-8100 model (manufactured by Kawaguchi Electric Seisakusho) was used to conduct The electrophotographic properties were investigated.

That is, the acceptance potential VA (V) when the surface of the photoreceptor is charged with a charging potential of -6 KV for 5 seconds and the potential (initial potential) Vl after dark decay for 5 seconds are adjusted so that the illuminance becomes 35 ffi IJX. Irradiate the surface with halogen lamp light to increase the surface potential to 17
Exposure amount required to attenuate to 2 El/2 1LIX
・Seconds) The results were as shown in Machine-1 below. However, sample 12 was charged at a charging potential of +6 KV for 5 seconds.

In addition, each of Samples 1 to 12 and Comparative Samples 1 to 5 was transferred to a dry electronic copying machine rU-B ix1550MR.
The black paper potential Vb (
V) and white paper potential Vw (V) were measured using an "electrostatic voltmeter 1440-1 D type" (manufactured by Monroe Electronics Inc.) immediately before development.

The results are shown in Table 1.

The black paper potential here refers to the surface potential of the photoreceptor when the above-mentioned copying cycle is performed using black paper with a reflection density of 1.3 as the original, and the white paper potential refers to the surface potential of the photoreceptor when the original is a black paper with a reflection density of 1.3. Represents the surface potential of the body.

However, in the table, ΔVb (V) and ΔVW (V) It are black paper potential vb (■) and white paper potential Vw (V), respectively.
Indicates the amount of fluctuation, + in the amount of fluctuation represents an increase, and - represents a decrease.

Margin below Furthermore, regarding sample 1 of the present invention, it was installed in a modified laser printer LP-3010 (manufactured by Konica), and the initial unexposed part potential (■H) and exposed part potential (VL
) and the differences ΔIVHI and ΔIVLI from the initial value of VHlVL after 20,000 copies were measured.

Also, when the amount of light required to make the charged potential ±600■ ±300 V is To (erg/cf),
O As a light source, the He/Ne laser (oscillation wavelength 6
32 nm) was used. These results are shown below.

V+ (V)--680 VL (V)--30 S λ (V -c f /er g ) -80
ΔIV) l 1 (■)--30 ΔIVL l (V)--15

[Brief explanation of the drawing]

1 to 9 are new views respectively showing structural examples of the photoreceptor of the present invention, and 1 to 6 in the figures represent the following, respectively. 1... Conductive support 2... Carrier generation layer 3.
...Carrier transport layer 4...Photosensitive layer 5...Intermediate layer
6...Protective layer patent applicant Konica Corporation
, Agent Patent Attorney Miyao Ichinose Figure 1 Figure 4 Figure 2 [Figure 5 Figure 3 Figure 6 I2 Kan 7 Figure Man'8 Figure 9

Claims (1)

[Scope of Claims] (1) In an electrophotographic photoreceptor having a photosensitive layer containing a carrier-generating substance and a carrier-transporting substance on a conductive support, at least one of the carrier-generating substances has the following general formula: An electrophotographic photoreceptor comprising a bisazo compound represented by [I], wherein at least one of the carrier transport substances comprises a compound represented by the following general formula [II]. General formula [I] ▲ Numerical formulas, chemical formulas, tables, etc. ▼ [X_1 and X_2 are each a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a nitro group, a cyano group, a hydroxy group or represents a substituted or unsubstituted amino group, and at least one of X_1 and X_2 is a halogen atom. p and q each represent an integer of 0, 1 or 2, p and q are never 0 at the same time, and p and q are 2
In this case, X_1 and X_2 may be the same or different groups, respectively. Q represents a group represented by the following general formula. General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, Ar represents an aromatic carbocyclic group having a fluorinated hydrocarbon group or an aromatic heterocyclic group having a fluorinated hydrocarbon group. Z is a substituted or represents a group of nonmetallic atoms necessary to form an unsubstituted aromatic carbocycle or a substituted or unsubstituted aromatic heterocycle). m and n are 0 and 1, respectively
or represents an integer of 2. However, m and n never become 0 at the same time. ] General formula [II] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, R_1 represents a substituted or unsubstituted naphthyl group, R_2 represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, and R_3 represents a hydrogen atom, an alkyl group, or an alkoxy group. R_4 and R_5
represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group. However, l is an integer of 0 or 1. ](
2) At least the uppermost layer of the photosensitive layer has the following general formula [A]
The electrophotographic photoreceptor according to claim 1, characterized in that the binder contains a polycarbonate represented by the following as a main component. General formula [A] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, R^1^3, R^1^4, R^1^5, R^1
^6, R^1^7, R^1^8, R^1^9, R^2^
0 represents a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic group, or a substituted or unsubstituted carbocyclic group, and n' is 10 to 1000. Z represents an atomic group necessary to form a substituted or unsubstituted carbocycle or a substituted or unsubstituted heterocycle. ] (3) A carrier generation layer in which the photosensitive layer contains a bisazo compound represented by the general formula [I] as a carrier-generating substance, and a carrier containing a compound represented by the general formula [II] as a carrier-transporting substance. The electrophotographic photoreceptor according to claim 1 or 2, characterized in that it has a laminated structure of transport layers. (4) Claim characterized in that the photosensitive layer further contains a compound having a hindered phenol structural unit (
The electrophotographic photoreceptor described in 1), (2) or (3).