JPS62116943A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body containing an electrostatic charge transfer material good in transmittance of light for generating charge, and having high sensitivity, low residual potential, and stability against oxidation, light and heat by forming on a conductive substrate a photosensitive layer containing at least one of specified bishydrazone compounds and bisstilbene compounds. CONSTITUTION:The photosensitive layer formed on the conductive substrate contains at least one of specified bishydrazone compounds and bisstilbene compounds represented by general formula I in which A is an atomic group represented by general formula II-V; each of R<1>-R<3> and R<5>-R<11> is alkyl, aralkyl, or aryl; R<4> is H, halogen (Hl), alkyl, alkoxy, aryl, or aryloxy; R<12> is H, Hl, nitro, cyano, alkyl, aralkyl, or aryl; Y is O, S, Se, imino, or methylene; Z is an atomic group necessary to form a benzene or naphthalene ring; Ar is an aromatic or heterocyclic group; i=1-7; k=0 or 1; and X is a specified cyclic atomic group.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention relates to an electrophotographic photoreceptor, and more particularly, an electrophotographic photoreceptor having a layer containing a novel charge-transporting substance and a novel photoconductive substance. The present invention relates to an electrophotographic photoreceptor having a layer t-.

"Conventional technology" The photoconductive process of electrophotographic photoreceptors is (I) Process of generating electric charge by exposure to light (2) Process of transporting all charges Consists of.

A selenium photosensitive plate is an example in which (I) and (2) are made of the same material. On the other hand, the combination of amorphous selenium and poly-N-vinylcarbazole is well known as an example of performing (I) and (2) using separate materials.A method of performing (I) and (2) using separate materials It has the advantage of expanding the selection range of materials used for the photoreceptor, improving the electrophotographic properties of the photoreceptor such as sensitivity and acceptance potential, and being able to select from a wide range of materials convenient for the production of photoreceptor coatings. have.

The basic characteristics required for such photoreceptors are:
(I) It can be charged to an appropriate potential in a dark place, (2) There is little dissipation of charge in a dark place, and (3) It has scales that quickly dissipate charge when irradiated with light. It is true that the conventionally used inorganic materials have many advantages, but also have various disadvantages. For example, selenium, which is currently widely used, fully satisfies the above conditions of fil~(3), but the manufacturing conditions are difficult, the manufacturing cost is high, it is not flexible, and it cannot be processed into a belt shape. It also has drawbacks such as being difficult and sensitive to heat and mechanical shock, requiring careful handling. Cadmium sulfide and zinc oxide are used as photoreceptors by being dispersed in a resin as a binder, but they cannot be used as is because of mechanical drawbacks such as smoothness, hardness, tensile strength, and abrasion resistance. cannot be used.

In recent years, electrophotographic photoreceptors using various organic materials for rounding that eliminate the drawbacks of these inorganic materials have been proposed, and some of them are in practical use. For example, poly-N-vinylcarbazole and 2. Hiroshi, photoreceptor consisting of 7-dolinitrofluorene-terone (US%, 4fit4
k, 237), poly-N-vinylcarbazole sensitized with pyrylium salt dye (Special Publication Show ψr-2zt
zr), and a photoreceptor containing a eutectic complex consisting of a dye and a resin as a main component (Japanese Patent Application Laid-Open No. 10711/1982).

Furthermore, a highly sensitive electrophotographic photoreceptor has been proposed that combines a substance that generates charge sound when exposed to light (called a charge-generating substance) and a substance that can transport the generated charge (called a charge-transporting substance). has been done. For example, U.S. Patent No.
7ri i, e2 is a photoreceptor in which a charge transport layer is provided on a charge generation layer, whereas in U.S. Pat. Further, U.S. Pat. No. 3,76≠ and U.S. Pat. No. 311 disclose photoreceptors having a photosensitive layer in which a charge generating material is dispersed in a charge transporting material. . Although many useful charge-generating substances have been proposed for this type of photoreceptor, the current situation is that very few truly useful charge-transporting substances have been proposed. A good charge-transporting material is one that sufficiently transmits light of a wavelength that causes charge generation from the charge-generating material, that has scales that maintain a sufficient potential when charged, and that the charge-generating material It has the ability to quickly transport the charges generated by the process.

As a result of intensive research, the present inventors discovered that a bishydrazone compound and a bisstilbene compound represented by the general formula (I) described later function effectively as a charge transport material for an electrophotographic photoreceptor, and thus the present invention was carried out. reached.

"Problems to be Solved by the Invention" An object of the present invention is to provide an electrophotographic photoreceptor having an electrophotographic photosensitive layer containing a charge transport material that is highly transparent to light having a wavelength that generates charges. .

Another object of the present invention is to provide an electrophotographic photoreceptor having an electrophotographic photosensitive layer with high sensitivity and low residual potential.

Still other objects of the present invention are that it is stable against oxidation caused by ozone generated by corona charging, light, and heat, has little dark decay of potential, has little increase or fluctuation in residual potential due to repeated use, and has low sensitivity fluctuations. An object of the present invention is to provide an electrophotographic photoreceptor having a stable electrophotographic photosensitive layer.

Still another object of the present invention is to provide an electrophotographic photosensitive layer which can be synthesized using a raw material compound that does not have toxicity or has low toxicity, and that contains a charge transport material that has no toxicity or has low toxicity. The object of the present invention is to provide an electrophotographic photoreceptor that has safe handling and disposal.

Still another object of the present invention is to provide a stable charge transport layer that has high film strength, excellent uniformity, and less fatigue deterioration.

"Means for Solving the Problems" The present invention provides an electrophotographic photosensitive layer comprising a photosensitive layer containing at least -[- of a bishydrazone compound or a bisstilbene compound represented by the following general formula (I). It's about the body.

In the formula, humans are atomic groups represented by the following general formulas (II) to (V).

(However, in general formulas (III) to (V), R1R8
, R9, R10 and R11 represent an alkyl group, an aralkyl group, an aryl group, or a substituent thereof.

R7, R8, R9, RIO and R11 may be the same or different (R, RH may be bonded to each other to form a heterocycle).

R12 represents a hydrogen atom, a halogen atom, a nitro group, a cyan group, an alkyl group, an aralkyl group, an aryl group, or a substituent thereof. Further, R 1 may combine with Ar to form an aromatic ring group.

Y represents an oxygen atom, a sulfur atom, a selenium atom, an unsubstituted or substituted imino group, or an unsubstituted or substituted methylene group.

Z represents an atomic group necessary to form a benzene or naphthalene ring. Z may have a substituent.

Ar represents a substituted or unsubstituted aromatic carbocyclic group or a substituted or unsubstituted aromatic heterocyclic group. ) R1, R2, R3, R5 and R6 represent a hydrogen atom, an alkyl group, an aralkyl group, an aryl group or a substituent thereof.

R1, R2, R3, R5 and R6 may be the same or different.

R4 represents a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkoxy group, an aryl group, an aryloxy group, or any substituted product thereof.

i represents an integer from / to 7.

k stands for 0 and fc stands for 75-.

It is an atomic group that is destroyed.

(However, R13 and R14 are hydrogen atoms, halogen atoms, alkyl groups, aralkyl groups, alkoxy groups, aryl groups,
Aryloxy group i represents these substituents, R%
R may be bonded to each other to form a condensed polycyclic aromatic ring.

L and n represent O or an integer from 1 to 6, and m represents O or an integer from 1 to 3. ) Further, the compound of the present invention will be explained in detail.

When R, R, R, R and R are linear or branched unsubstituted alkyl groups having 1 to 12 carbon atoms, specific examples thereof include methyl group, ethyl group, propyl group, butyl group, pentyl group. group, hexyl group, octyl group, nonyl group, dodecyl group, inpropyl group, isobutyl group, inpentyl group, μm methylpentyl group, 5e
There are c-butyl group and tert-butyl group. Substituent 'k
In the case of an alkyl group with W, specific examples of substituents include:
Halogen atoms include chlorine, bromine, and fluorine; alkoxy groups include methoxy, ethoxy, propoxy, butoxy, and inthyloxy; aryloxy groups include phenoxy, 0-tolyloxy, m-)lyloxy, and p
-Tolyloxy group, l-naphthyloxy group, λ-naphthyloxy group, dimethylamino group, diethylamino group, dipropylamino group, N-methyl-N-ethylamino group, N-ethyl-N-propylamino group as dialkylamino group group, N-methyl-N-propylamino group, diphenylamino group as diarylamino group, methylthio group, ethylthio group, propylthio group as alkylthio group, piperidino group as N-containing heterocyclyl group, l-pi is radicalinyl group, morpholino group group, l-pyrrolidyl group. An alkyl group in which at least one of these substituents is bonded to any carbon atom of the above-mentioned alkyl group is an example of an alkyl group overlying the substituent.

When RX R8, R9, RIO and R are linear or branched unsubstituted aralkyl groups having 7 to 20 carbon atoms, specific examples thereof include benzyl group, phenethyl group, l
-naphthylmethyl group, λ-naphthylmethyl group, l-anthrylmethyl group, and benzhydryl group. In the case of an aralkyl group containing a substituent, specific examples of the substituent include the same group as the substituent of the alkyl group having the above-mentioned substituents, and any of these substituents may be any carbon of the above-mentioned aralkyl group. An aralkyl group bonded to at least/atom is an example of an aralkyl group having a substituent.

FL, FL, R9, RIO and R are monocyclic or hydrogen atoms of a condensed polycyclic aromatic hydrocarbon having 2 to μ rings, r
When the unsubstituted aryl group is a monovalent group excluding /, specific examples include phenyl group, l-naphthyl group, λ-naphthyl group, anthryl group, pyrenyl group, acenaphthynyl group, and fluorenyl group. In the case of an alkyl group having a substituent, specific examples of the substituent include the same substituents as those of the alkyl group having a substituent mentioned above, and other alkyl groups such as a methyl group, an ethyl group, a propyl group, and a butyl group. group, pentyl group, isopropyl group, isobutyl group, isointyl group is an aryl group, and at least one of these substituents is bonded to a carbon atom of the above-mentioned aryl group. This is an example.

A specific example of the heterocycle when R7 and R form a heterocycle is a carbazole ring.

Specific examples of R12 being an unsubstituted or substituted alkyl group, an unsubstituted or substituted aralkyl group, and an unsubstituted or substituted aryl group are the same as those for R above.

When R12 is a halogen atom, specific examples include a chlorine atom, a bromine atom, and a fluorine atom.

Further, when R12 and Ar combine with each other to form an aromatic ring group, a specific example thereof is a 9-fluorenyl group.

When Ar is an unsubstituted aromatic carbocyclic group, specific examples include phenyl group, naphthyl group, anthryl group, pyrenyl group,
Specific examples include an acenaphthynyl group and a fluorenyl group. When Ar is an unsubstituted aromatic heterocyclic group, specific examples include a pyridyl group, a chenyl group, and a carbazolyl group.

When Ar is an aromatic carbocyclic group or an aromatic heterocyclic group having a substituent, specific examples of the cypress core include the above-mentioned specific examples of the substituent when R7 is an aryl group having a substituent. We can give the same base.

R1, R2, R3, B4, R5, R6, R13 and R14 are unsubstituted or substituted alkyl groups,
Specific examples of the unsubstituted or substituted aralkyl group and the unsubstituted or substituted aryl group are the same as those for R7 above.

When R4, R13, and R14 are a halogen atom, an alkoxy group, or an aryloxy group, specific examples include chlorine, bromine, or fluorine as the halogen atom, and a methoxy group, ethoxy group, propoxy group, butoxy group as the alkoxy group,
Examples of the pentyloxy group and aryloxy group include phenoxy group, 0-tolyloxy group, m-tolyloxy group, p-tolyloxy group, /-naphthyloxy group, and λ-naphthyloxy group.

The number of R4 may be an integer of / to 2, and may be the same or different.

Specific examples of X include a methylene group, an ethylene group, a propylene group, a butylene group, a butylene group, a hexylene group, a laurilene group, a p-xylylene group, and x.

! -dichloro, p-xylylene group, co, 3. j.

These include 6-tetramethyl, p-xylylene group, and 4t-dimethylenenaphthalene group.

When 2 has a substituent, specific examples of the substituent include the same substituents as the above-mentioned substituent when R is an aryl group having a substituent.

Preferred groups among R7,H are one in which one is a phenyl group,
The other is a methyl group, ethyl group, benzyl group, phenyl group,
or naphthyl group.

Preferred groups among R9 and RIO are phenyl group, dimethylaminophenyl group, and diethylaminophenyl group.

R11 is preferably a methyl group, an ethyl group, or a benzyl group.

As R12, a hydrogen atom is preferable.

As Y, a sulfur atom is preferable.

Z is preferably an atomic group necessary to form a benzene ring.

As Ar, a substituted phenyl group is preferable, and as a substituent, an alkyl group with a carbon number of 7 to 7 g is preferable, and an alkoxy group with a carbon number of 7 to 7 g is preferable.

Preferred examples of R1 include a hydrogen atom, a methyl group, an ethyl group, a phenyl group, a benzyl group, a p-(dimethylamino)phenyl group, and a p-(diethylamino)phenyl group, and a hydrogen atom is particularly preferred as R1. .

Hydrogen atoms are preferred as R2, R3, R5, and H6.

Preferred examples of R4 include a hydrogen atom, a methyl group, an ethyl group, a methoxy group, an ethoxy group, a fluorine atom, a chlorine atom, and a bromine atom.

Preferred examples of X are ethylene group, butylene group, intylene group, hexylene group, and p-xylylene group.

Specific examples of the bishydrazone compound and bisstilbene compound represented by the general formula (I) are shown below.

The bishydrazone compound represented by the general formula (I) is represented by the general formulas [■] to (IX).

Hydrazine or its mineral acid salt and the biscarbonyl compound represented by the general formula [X] are reacted in a solvent by a conventional method by adding a small amount of acid (glacial acetic acid or inorganic acid) as a condensing agent if necessary. You can get it by doing this. As the solvent, alcohols such as methanol and ethanol, tetrahydrofuran, acetic acid, etc. can be used alone or in combination.

(In the formula, R1-R11,

It has the same meaning as k. ) Furthermore, the bisstilbene compound represented by the general formula (I) is obtained by combining the compound represented by the general formula (XI) and the biscarbonyl compound represented by the above-mentioned general formula [X] into DM.
It can be easily obtained by reaction in an organic solvent such as F in the presence of an appropriate base (eg, sodium hydroxide, sodium methoxide, potassium t-butoxite, etc.).

Ar -CH2Q (M) (wherein, Ar is represented by the same rutriphenylphosphonium a or PO(OR')2 as Ar in the above general formula (I) (wherein R' represents a lower alkyl group) (It is a dialkyl parallel phosphoric acid group.) The compound represented by the general formula [X] is US3゜!4t4
t,2irK can be synthesized according to the disclosed method.

The photoreceptor of the present invention contains the above-mentioned bishydrazone compound or bisstilbene compound, but depending on the application of these compounds, they can be used as shown in FIGS. can.

The photoreceptor shown in FIG. 1 has a photosensitive layer 2/ made of a bishydrazone compound or a bisstilbene compound, a sensitizing dye, and a binder (resin) on a conductive support 2/. The photoreceptor shown in Figure 1 has a photosensitive layer disposed on a conductive support, in which a charge generating substance 3 is dispersed in a charge transporting medium consisting of a bishydrazone compound or a bisstilbene compound and a binder. It is.

The photoreceptor in FIG. 3 has a charge generating material 3 on a conductive support.
A charge generation layer mainly composed of! and a photosensitive layer λ3 consisting of a charge transport layer containing a bishydrazone compound or a bisstilbene compound.

The photoreceptor shown in FIG. 9 has a charge transport layer containing a bishydrazone compound or a bisstilbene compound on a conductive support, and a charge generation layer containing a charge generation substance 3 on top of the charge transport layer. A photosensitive layer λ is provided.

In the photoreceptors shown in FIGS. 3 and 9, the charge generation layer contains the charge generation substance 3 and a bishydrazone compound or a bisstilbene compound! In this case, the charge transport layer may contain a charge transport material other than the bishydrazone compound or bisstilbene compound of the present invention.

In the photoreceptor of FIG. 7, the bishydrazone compound or bisstilbene compound acts as a photoconductive material, and the generation and transport of the charge carriers necessary for light attenuation is carried out through the bishydrazone compound or bisstilbene compound. However, bishydrazone compounds or bisstilbene compounds have almost no absorption in the visible region of light, so for the purpose of forming images with visible light, a sensitizing dye that absorbs in the visible region is added. I need to feel it.

In the case of the photoreceptor of Figure 2, a bishydrazone compound or a bisstilbene compound forms the charge transport medium with a binder (or binder and plasticizer) while a charge generating material such as an inorganic or organic pigment generates an electric charge.

In this case, the charge transport medium mainly has the ability to accept and transport charges generated by the charge generating substance. Here, the charge-generating substance and the charge-transporting compound interact with each other.
The basic condition is that the absorption wavelength regions do not overlap, mainly in the visible region. This is because in order to efficiently generate charges in the charge generating material, it is necessary to transmit light to the surface of the charge generating material. The bisstilbene compound described in the present invention has almost no absorption in the visible region, and when combined with a charge-generating substance that generally absorbs light in the visible region and generates charges, it works particularly effectively as a charge transport material. It is.

In the photoreceptor shown in Figure 3, the light that has passed through the charge transport layer is the charge generation layer! , and charge generation occurs in that region, while the charge transport layer receives charge injection and transfers it.The charge generation material necessary for light attenuation is generated by the charge generation material; The mechanism in which charge transport is carried out by a charge transport medium (mainly the bishydrazone compound or bisstilbene compound of the present invention) is the same as in the case of the photoreceptor shown in FIG. Again, the bishydrazone compound or bisstilbene compound acts as a charge transport material.

In the photoreceptor shown in Figure 9, a charge generation layer is generated by light! In the process, charge generation occurs, while the charge transport layer receives charge injection and transports it. Charge generation necessary for light attenuation,
The mechanism of charge transport is the same as that of the photoreceptor shown in FIGS. 2 and 3. Again, the bishydrazone compound or bisstilbene compound acts as a charge transport substance.

To produce the photoreceptor shown in Fig. 7, a bishydrazone compound and a bisstilbene compound are dissolved in a solution containing a binder, and if necessary, a sensitizing dye is added thereto, and the solution is placed on a conductive support. Apply and dry. To prepare the photoreceptor shown in FIG. 2, fine particles of a charge generating substance are dispersed in a solution containing a bishydrazone compound, a bisstilbene compound and a binder, and the particles are coated on a conductive support and dried. The photoreceptor shown in Fig. 3 is produced by vacuum-depositing a charge-generating substance on a conductive support, or by dispersing fine particles of a charge-generating substance in a suitable solvent in which a binder is dissolved as necessary. The resulting dispersion is coated and dried, and if necessary, the surface is finished by a method such as e-polishing or the film thickness is adjusted, and then a bishydrazone compound or a bisstilbene compound and a Applying a solution containing a binder,
Obtained by drying. Application is carried out using conventional means, such as a doctor blade or a wire parser.

The photoreceptor shown in FIG. 9 is prepared by applying a solution containing a bishydrodicine compound or a bisstilbene compound and a binder onto a conductive support by a conventional method and drying it, and then using the same method as the photoreceptor shown in FIG. 3. This can be obtained by providing a charge generation layer.

The thickness of the photosensitive layer is 7 to 10 in the ones in Figures 1 and 2.
μm1 is preferably 1 to 20 μm.

In addition, in the cases of FIGS. 3 and 9, the thickness of the charge generation layer is
The thickness of the charge transport layer is 3 μm or less, preferably 1 μm or less, and the thickness of the charge transport layer is 3 μm or less! Oμm1 is preferably 5 to 20 μm. In the photoreceptor shown in FIG. 1, the proportion of the bishydrazone compound or bisstilbene compound in the photosensitive layer is 70 to 70% by weight, preferably 30 to 70% by weight, based on the photosensitive layer.

The sensitizing dye used to impart photosensitivity in the visible region is 0.1 to 1% by weight, preferably 0.1 to 1% by weight, based on the photosensitive layer. t~3% by weight. In the photoreceptor shown in FIG. 2, the proportion of the bishydrazone compound or bisstilbene compound in the photosensitive layer is 10 to 9! Weight rating, preferably 30-90
% by weight, and the proportion of charge-generating substances! Q weight ratio or less, preferably 20% by weight or less. The ratio of the bishydrazone compound or bisstilbene compound during charge transport in the photoreceptors shown in FIGS. 3 and 9 is 10 to 9! as in the case of the photosensitive layer shown in FIG. 2! % by weight, preferably 30-90
Weight -. In addition, the charge generating substance in the charge generating layer is 10 to 0% by weight, preferably 20 to 0% by weight when a bishydrazone compound or a bisstilbene compound is not added at the same time.
When simultaneously adding a bishydrazone compound or a bisstilbene compound at a ratio of 70% by weight, the charge generating agent is added at 0.0/-0% by weight, preferably from 0.01 to 20% by weight of a bishydrazone compound or a bis-stilbene compound. or 0.07 to 20% by weight of a bisstilbene compound, preferably O1θ! ~!
It is used in a proportion of θ% by weight. Incidentally, in the production of any of the photoreceptors shown in FIGS. 1-g, a plasticizer can be used together with a binder.

In the photoreceptor of the present invention, as the conductive support, a metal plate or foil made of aluminum or the like, a plastic film deposited with a metal such as aluminum, or paper treated with electrical conductivity is used. As a binder,
Condensation resins such as polyamide, polyurethane, polyester, epoxy resin, polyketone, polycarbonate,
Vinyl polymers such as polyhinyl ketone, polystyrene, poly-N-vinylcarbasol, and polyacrylamide are used, but any insulating and adhesive resin can be used.

As the plasticizer, halogenated paraffin, polychlorinated piphenyl, dimethylnaphthalene, dibutyl phthalate, etc. are used.

The sensitizing dyes used in the photoreceptor shown in FIG.
Rhodamine to G, Rhodamine G Extra, Eosin S1 Erythrosine, Rose Bengal, Xanthine dyes such as fluorescein, Thiazine dyes such as methylene blue, C,1, Ba5ic, Violety (C,
Astrazone dyes such as 1,4t, ro2o), cyanine dyes such as cyanine L-! , t-diphenyl-
y-(N,N-dimethylaminophenyl)thiapyrylium verchlorate, benzopyrylium salt (% Kosho 4t/
-2!6, described in No. 2) and other biryllium dyes.

Examples of charge-generating materials used in the photoreceptors shown in FIGS. 2, 3, and 9 are as follows.

(I) Selenium and selenium alloys (2) CdS, CdSe, Cd5Se,
Inorganic photoconductors such as ZnO and ZnS (3) Metal phthalocyanines and metal-free phthalocyanine nato phthalocyanine pigments (4) Azo pigments For example, JP-A-Sho! Azo pigments having a carbazole skeleton as described in JP-A No. 3-93033;
Azo pigments having a triphenylamine skeleton as described in No. 1321417, JP-A-Sho! 3-/3j4t
4tj issue or JP-A-Shoj9-4t2! ! Azo pigments having a styrylstilbene skeleton as described in No.
Tokukai Akira! ♂-723!4t/issue or Tokukai Sho! ? -ko/7
3! An azo pigment having a naphthalene skeleton as described in No. A, JP-A-Sho! ♂-2/7-t! Trisazo pigment as described in No. 6, JP-A-Sho J-9-2234tJ
These include azo pigments having a thiophene skeleton, such as those described in No. j.

(5) Rylene pigments such as halylenoic anhydride and perylenic acid imide; (6) Indigoid dyes (quinacridone pigments; (8) polycyclic quinones such as anthraquinones, pyrenequinones, anthoanthrones, and flavanthrones; ) Bisbenzimidazole pigment αQ Cyanine dye αυ Square methine dye (I) Indanthrone pigment αj Xanthine dye I From an electron-donating substance such as poly-N-vinylcarbazole and an electron-accepting substance such as trinitrofluorenone A charge transfer complex α9 consisting of a eutectic complex formed from a pyrylium salt dye and a polycarbonate resin, and (I6) amorphous silicon.

It is particularly preferred to use an azo pigment as the charge generating substance.

In the photoreceptor obtained as described above, an adhesive layer or a barrier layer can be provided between the conductive support and the photosensitive layer, if necessary. Materials used for these layers include, in addition to the high molecular weight polymer used as the binder, gelatin, casein, polyvinyl alcohol, ethyl cellulose, carboxy-methyl cellulose, and percent starch.
Vinylidene chloride polymer latex described in No. 4t2<t7, JP-A-Shoj? -//<<styrene-butadiene polymer latex described in JGG issue, etc., and the thickness of these layers is preferably 7 μm or less.

The electrophotographic photoreceptor of the present invention has been described in detail above, and the electrophotographic photoreceptor of the present invention generally has the characteristics of high sensitivity and excellent durability.

The electrophotographic photoreceptor of the present invention can be used in an electrophotographic copying machine or a laser.
It can be widely applied to fields such as photoreceptors in printers that use cathode ray tubes as light sources.

Other uses of the photoreceptor of the present invention include Japanese Patent Publication No. 37-77
No. 742, Tokukai Shojj-/9θ Otsu No. 3, Tokukai Sho! ! −／
As disclosed in Japanese Unexamined Patent Publication No. 37-10 and JP-A No. 1988/G7TJD, the bisstilbene compound or bisstilbene compound of the present invention is added to an alkali-soluble resin solution such as a 7-enol resin together with the above-mentioned charge generating substance. After being dispersed and coated on a conductive support such as aluminum, and dried,
By image exposure, toner development, and etching with an alkaline aqueous solution, printing plates with high resolution, high durability, and high sensitivity can be obtained, and printed circuits can also be created.

"Examples" Next, the present invention will be specifically explained using Examples, but the present invention is not limited to the Examples. In the examples, "parts" indicate "parts by weight."

Synthesis example US3. r/14t, 7/j, the following dimeric formylcarbazole (I) - (
iii) was synthesized.

Next, this dimeric formylcarbazole (i) is mixed with hydrochloric acid/,/-diphenylhydrazine.

λg1 sodium acetate/, θg, jOml DMF
The mixture was heated and stirred in a solvent for 0.613 hours.

After the reaction was completed, the precipitate obtained by pouring into 1.21 water was 3.
! g was dissolved in acetone and reprecipitated in MeOH for purification.

The melting point of Compound Example (I) thus obtained is /r
It was o'c.

Dimeric formylcarbazole (Ij) or (ii
Specific compound example (2) or (3) was obtained by the same operation using each of i).

Its melting point is s2t'c or l!, respectively. o'
It was C.

Other compounds can be easily obtained by similar operations.

Example/Selenium was vacuum-deposited to a thickness of 0.92 m on a grained aluminum plate having a thickness of about 300 μm to form a charge generation layer. On top of this, 10 parts of the bishydrazone compound represented by the specific example (I) of the compound of the general formula (summer) and 70 parts of polycarbonate of bisphenol A (manufactured by Konjin, -73°θθ in ξ) were added. Dichloromethane/30
The solution was applied using a wire round iron and dried to form a charge transport layer having a thickness of about /-μm. In this way, an electrophotographic photoreceptor having a photosensitive layer consisting of a co-layer was obtained.

This photoreceptor was tested using an electrostatic copying paper tester (manufactured by Kawaguchi Electric Seisakusho Co., Ltd., SP-Kuko♂ type).

Negatively charged by corona discharge of KV, then 2r
Irradiate the surface with light using a tungsten lamp at ra 0 at an illuminance of 2.0 lux, find the time required for the surface potential to decay to a fraction of the initial surface potential, and calculate the exposure time t( Eso: 11ux-sec
) was obtained.

The result was E50''!, 1jux-3ec.

[E50 after repeating V exposure 3θ0θ times is ♂,
9 flux·See, and the fluctuation in sensitivity is extremely small.

K in place of bishydrazone compound (I) in Example 2 to Example B, specific examples of compounds represented by the above-mentioned general formula (I) (2), (3), bishydrazone represented by αυ, 11αη, respectively A photoreceptor having a two-layer structure was prepared in the same manner as in Example 1, except that the compound or bisstilbene compound was used, and the half-decreased exposure amount (Eso) due to negative charging was measured in the same manner as in Example 1. The values shown are obtained.

Table 1 Example 7 β-type steel 7 Talocyanine! of bisphenol A was added to 727,310 parts of dichloromethane, and after ultrasonic dispersion, 4 parts of bisphenol A polycarbonate (173 oo of Hanlite) was added to this dispersion.
To part and <10 parts of a bishydrazone compound represented by specific example (I) of the compound represented by general formula (I) described above were added and dissolved to prepare a coating solution. This coating solution was applied to a conductive transparent support (IO) using a wire round rod.
A vapor-deposited film of indium oxide is formed on a 0 μm polyethylene terephthalate support. Surface resistance/θ3Ω. ) and dried to obtain a photoreceptor with a thickness of about io μm.

After this photoreceptor was positively charged by +rKV corona discharge, the half-life exposure (Eso) was measured. B So =
r, j 1uX-1!4@e.

Example? 4 parts of trisazo pigment with the following structural formula and polyester resin (
Toyobo Co., Ltd., Byron, 2oo) g parts were added to the tetrahydrofrank part and dispersed in a ball mill for 72 hours. The dispersion was then transferred to a conductive support (7002m polyethylene terephthalate support) using a wire round rod. Has an aluminum vapor deposited film on top.Surface resistance 4
tX102Ω) and dried to a thickness of about θ,! A charge generation layer of μm was obtained.

Next, a bishydrazone compound represented by the specific example (2) of the compound represented by the general formula (I)/theta-part tobisphenol A polycarbonate (Hanlite to 113
A solution prepared by dissolving oo) and io parts in dichloromethane/2θ parts was applied using a wire round rod and dried to form a charge transport layer with a thickness of about 4 tμm.

The half-life exposure (Eso) of the two-layer photoreceptor thus obtained was measured in the same manner as in Example 1, and was found to be 41 uX-1iec.

Examples 9 to 7 Specific examples (4), (7), (9), (I( L (I21, (I4
)

In the same manner as in Example/, the half-reduced exposure amount (Eso
) was measured and the values shown in Table 1 were obtained.

Table 2 Example/r Specific example (2) of the compound represented by the above general formula (I)
70 parts of bishydrazone compound, 70 parts of bisphenol A polycarbonate (Panlite-yiθθ), and 7 Strazone dye θ having the following structural formula.

A coating solution was prepared by adding and dissolving 72 parts of the above solution in 110 parts of dichloromethane.

This coating solution was coated on a conductive transparent support (having a vapor-deposited film of indium monoxide on a polyethylene terephthalate support of I0 Opm, surface resistance: 103Ω) using a wire round rod, and dried to a thickness of about 70 μm. A photoreceptor was obtained.

After this photoreceptor was positively charged by +tKV corona discharge, the half-life exposure (Eso) was measured, and E50 =
20, J 7ux-sec.

(Astrazone pigment) 6aa c, o, e Example/9 Trisazo pigment used in Example ♂! part and the aforementioned general formula (
Specific example of the compound represented by I) <10 parts of the bishydrazone compound represented by (2) and a copolymer of benzyl methacrylate and methacrylic acid ([η:]3o 0C
Methyl ethyl ketone (o, i, z, methacrylic acid content: 32.9%), tOo parts, were added to 110 parts of dichloromethane and subjected to ultrasonic dispersion. This dispersion was coated on a grained aluminum plate with a thickness of 0.23 mm and dried to prepare an electrophotographic photosensitive printing plate material having an electrophotographic photosensitive layer with a dry film thickness of mm.

After charging the surface potential of the photosensitive layer to +ooV by corona discharge (+aKV) on this sample in a dark place, tungsten light with a color temperature of λ♂, t4t' is applied to the sample surface with an illuminance of 2. .0 Lutsukuzu exposure, half-reduced exposure (Eso)
is 11. θflux-see.

Next, this sample was charged to a surface potential of about +4 tOoV in a dark place, and then brought into close contact with a transparent original with a positive image, and imagewise exposed. This was mixed with l5oper H (manufactured by Esso Standard Co., Ltd., containing polymethyl methacrylate (toner) tg dispersed in fine particles in a petroleum-based solvent and a toner prepared by adding 0.0/g of soybean oil lecithin. When immersed in a liquid developer, a clear positive toner image could be obtained.

Further, the toner image was fixed by heating at 10°C for 3θ seconds. This printing plate material was mixed with 20g of sodium metasilicate hydrate.
Glycerin/4tOml, ethylene glycol rjo
mlz oyohi ethanol l! Approximately 7
By immersing it for a minute and washing it with water while lightly brushing it, the electrophotographic photosensitive layer in the areas to which toner was not attached was removed, and a printing plate was obtained.

Also, instead of using liquid developer, the obtained electrostatic latent image can be used with Xerox 3! After developing with a magnetic brush using a θθ toner (manufactured by Fuji Xerox ■), it was heated and fixed at rooC for 30 seconds. Next, a printing plate was also obtained by removing the photosensitive layer in the areas to which toner was not attached using an alkaline solution.

The printing plate produced in this way is used as a Huff Duster 6ooCD.
When printed using an offset printing machine, the prints are very clear and have no background smudges! I was able to print out the cane.

Example 20 Three parts of the bishydrazone compound represented by specific example (2) and a polyester resin (trade name: Pyronco θQ1 Toyobo ■
Disazo pigment with the following structure along with a solution of 1 part (manufactured by ) dissolved in 4t4 parts of tetrahydrofuran! After adding g and dispersing in a ball mill for -0 hours, a conductive support (a 7 μm polyethylene terephthalate film with an aluminum evaporated film provided on the surface) was prepared using a wire round rod.

It is coated on a surface (surface electrical resistance: 103Ω) and dried to a thickness of 0.
A charge generation layer having a thickness of 1 μm was prepared.

Next, on the charge generation layer, 2.4 parts of a hydrazone compound which is a charge transport substance having the following structure (hydrazone compound), 9 parts of polycarbonate of bisphenol A, and 3.3 parts i of dichloromethane, J-cycloep72t,
A solution in which the
An electrophotographic photoreceptor having an electrophotographic photosensitive layer consisting of layers was prepared. (Referred to as Sample A) On the other hand, for comparison, a Comparative Sample B was prepared, corresponding to Sample A, in which the bishydrazone compound (2) was not added to the charge generation layer.

This electrophotographic photoreceptor was tested for -? by corona discharge at +rKV using an electrostatic copying paper tester (model 5P-4tsr manufactured by Yoro Denki ■). Charged to 0θV, then color temperature 5t
Light was irradiated with a tungsten lamp at rr4t 0 so that the surface became colux, and the time required for the surface potential to attenuate to half of the initial surface potential was determined and E50 was measured.

The results were as follows.

Sample A E5Q = 2, 0 1ux-sec Comparative sample BE5g = j, 41 1ux-sec Furthermore,
This charging and exposure process was repeated 20[theta] times to measure the first initial potential (V) and the charging (V) after repeating 200 times.

From the above results, sample A in which a bisstilbene compound was added to the charge generation layer had superior sensitivity compared to comparative sample B1.
It was also found that the decrease in charging potential after repeated cycles was significantly improved compared to Comparative Sample B.

Examples 27-2g To the base of the bishydrazone compound (2) added to the charge generation layer of Example 23, compounds (I), (3), and
An electrophotographic photoreceptor was prepared in the same manner as in Example 0, except that (8), (I3, (I1), and (21)) were used.

-, <KV was charged by corona discharge, and E5° was measured.

Further, this charging and exposure process was repeated 200 times, and the variation in charging potential was measured.

The results are shown below.

From the results of Example jO-24, the sample in which a bishydrazone compound or a bisstilbene compound was added to the charge generation layer was superior in sensitivity to Comparative Sample B, and the charge potential after repeated cycling was lower than that of Comparative Sample. It was found that this was significantly improved compared to B.

[Brief explanation of drawings]

1 to 9 are cross-sectional views enlarged in the thickness direction of an electrophotographic photoreceptor according to the present invention. The numbers in the figure indicate the following. /... conductive support, 2/, 22, 23.2'l...
- Photosensitive layer, 3... Charge generating substance, G... Charge transport layer,! ...charge generation layer

Claims (1)

[Scope of Claims] An electrophotographic photoreceptor characterized in that a photosensitive layer containing at least one of a bishydrazone compound or a bisstilbene compound represented by the following general formula (I) is provided on a conductive support. . ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) In the formula, A is an atomic group represented by the following general formulas (II) to (V). ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II), ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (III) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (IV), ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼(IV) (However, in general formulas (II) to (V), R^7, R^
8, R^9, R^1^0 and R^1^1 represent an alkyl group, an aralkyl group, an aryl group, or a substituent thereof. R^7, R^8, R^9, R^1^0 and R^1^1
may be the same or different from each other, R^7, R^8
may be combined with each other to form a heterocycle. R^1^2 represents a hydrogen atom, a halogen atom, a nitro group, a cyano group, an alkyl group, an aralkyl group, an aryl group, or a substituted product thereof. Further, R^1^2 may be bonded to Ar to form an aromatic ring group. Y represents an oxygen atom, a sulfur atom, a selenium atom, an unsubstituted or substituted imino group, or an unsubstituted or substituted methylene group. Z represents an atomic group necessary to form a benzene or naphthalene ring. Ar represents a substituted or unsubstituted aromatic carbocyclic group or a substituted or unsubstituted aromatic heterocyclic group. ) R^1, R^2, R^3, R^5 and R^6 represent a hydrogen atom, an alkyl group, an aralkyl group, an aryl group, or a substituent thereof. R^1, R^2, R^3, R^5 and R^6 may be the same or different. R^4 represents a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkoxy group, an aryl group, an aryloxy group, or a substituted product thereof. i represents an integer from 1 to 7. k represents 0 or 1. X is an atomic group represented by the following general formula (VI). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(VI) (However, R^1^3 and R^1^4 are hydrogen atoms, halogen atoms, alkyl groups, aralkyl groups, alkoxy groups, aryl groups, aryloxy groups, or Representing these substituents, R^1^3 and R^1^4 may be combined with each other to form a condensed polycyclic aromatic ring. l and n are 0 or an integer of 1 to 6, m represents 0 or an integer from 1 to 3.)