JPS5929250A - Electrophotographic receptor - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic receptor having a low molecular org. photoconductor giving improved electrophotographic characteristics by forming a layer contg. a specified hydrazone compound on an electrophotographic receptor. CONSTITUTION:A layer contg. a hydrazone compound represented by formula I (where each of R1 and R2 is optionally substituted alkyl, aralkyl, phenyl or a residue forming a 5- or 6-membered ring together with N; each of R3 and R4 is alkyl or alkoxy; each of R5 and R6 is alkyl, optionally substituted aralkyl or aryl; and n is 0 or 1) is formed on an electrophotographic receptor. For example, a compound represented by formula II, III or IV is contained as the compound represented by the formula I . The hydrazone compound represented by the formula I is preferably used as a charge transferring substance in an electrophotographic receptor having a separated function type photosensitive layer consisting of a charge generating layer and a charge transferring layer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photoreceptor, and more particularly to a photoconductor having a low molecular weight organic photoconductor that provides improved photographic properties. It is.

Conventionally, inorganic photoconductive materials such as selenium, cadmium sulfide, and zinc oxide are known as photoconductive materials used in electrophotographic photoreceptors. These photoconducting TIIL materials have a number of advantages, including the ability to be charged to a suitable potential in the dark;
Although it has advantages such as less charge dissipation in the dark and the ability to quickly dissipate charge by irradiation with light,
It has various drawbacks. For example, selenium-based photoreceptors easily crystallize due to factors such as temperature, humidity, dust, and pressure. Especially when the ambient temperature exceeds 40°C, crystallization becomes significant, resulting in a decrease in chargeability and damage to the image. It has the disadvantage of causing white spots. Cadmium sulfide photoreceptors have the disadvantage that stable sensitivity cannot be obtained in humid environments, and zinc oxide photoreceptors require the sensitizing effect of sensitizing dyes such as rose bengal. The sensitizing dye suffers from charging deterioration due to corona charging and photobleaching due to exposure light, so it has the disadvantage that it cannot provide stable images over a long period of time.

On the other hand, various organic photoconductive polymers including polyvinylcarbazole have been proposed, but these polyv- are inferior in terms of film formability, light weight, etc. compared to the inorganic photoconductive materials mentioned in 111. Despite its excellent properties, it has been difficult to put it into practical use until now because it has not yet achieved sufficient film formation properties, and because of its sensitivity, durability, and stability against environmental changes, inorganic This is because it is inferior to photoconductive materials. In addition, hydrazone compounds disclosed in U.S. Pat. No. 4,150,987, triarylpyrazoline compounds described in U.S. Pat.
A low-molecular organic light guide tube such as a 9-styrylanthracene compound described in Japanese Patent Publication No. 2003-100000 has been proposed. Such low-molecular-weight organic photoconductors can overcome the film-forming defects that had been a problem in the field of organic photoconductive fW polymers by appropriately selecting the binder used. However, it cannot be said to be sufficient in terms of sensitivity.

For these reasons, a laminated structure in which the photosensitive layer is functionally separated into a charge generation layer and a charge transport layer has been proposed in recent years. This P
Electrophotographic photoreceptors having the A-layer structure as a photosensitive layer can now be improved in terms of sensitivity to visible light, charge retention surface strength, etc.

Such an electrophotographic photoreceptor is disclosed in US Pat. No. 3,837, for example.
It is disclosed in No. 851, No. 413871882, etc.

However, electrophotographic photoreceptors using conventional low-molecular-weight organic photoconductors in the charge transport layer have not yet achieved sufficient sensitivity, and when repeatedly charged and exposed, the bright area potential does not change. There are large fluctuations in the dark potential, and there are points that need improvement.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photoreceptor that eliminates the above-mentioned drawbacks or disadvantages.

Another object of the invention is to provide novel organic photoconductors.

Another object of the present invention is to provide a novel charge transport material in a laminated photosensitive layer in which a charge generation layer and a charge transport layer are functionally separated.

This object of the present invention is achieved by an electrophotographic photoreceptor having a layer containing a hydrazone compound represented by the following general formula (1).

In the general formula, R1 and R2 represent an alkyl group such as methyl, ethyl, propyl, butyl, an aralkyl group such as benzyl, phenethyl, naphthylmethyl, or a phenyl group, and the alkyl group is methoxy, ethoxy, pro1j soxy, butoxy. an alkoxy group such as fluorine, chlorine, bromine, iodine, etc., or a dialkylamino group such as dimethylamino, diethylamino, dipropylamino, diethylamino, etc.
E! The aralkyl group and the phenyl group are alkyl groups such as methyl, ethyl, propyl, butyl, alkoxy groups such as methoxy, ethoxy, butoxy, fluorine, chlorine, bromine, iodine, etc. may be substituted with a halogen atom or a dialkylamino group such as dimethylamino, diethylamine, dipropylamino, or dibutylamino. In addition to R1 and R2, this represents a residue that forms a 5- to 6-membered ring group such as a pyrrolidino group, piperidino group, or morpholino group together with an N atom, and is an alkyl group such as megyl, ethyl, propyl, butyl, etc. group or methoxy,
Represents an alkoxy group such as ethoxy, propoxy, butoxy, R15% R6 is an alkyl group such as methyl, ethyl, propyl, butyl, an aralkyl group such as benzyl, phenethyl, naphthylmethyl, or an aryl group such as benzene, naphthalene, anthene, etc. shows. The aralkyl group and aryl group are the aralkyl group and phenyl group of R1 and R2! l! ! It may be substituted with the same substituent group as the group or with a different group.

n represents an integer of 0 or 1.

Typical compound examples are shown below.

Sample example H-(8) h3 lily )f-(+13 H-1t )? -+14> 11502υ Next, a typical synthesis example will be shown.

Synthesis of H-(1) compound N-phenyl-α-naphdylane 51.8F (0,2
56 mol) was dissolved in a mixed solvent consisting of 240 m of ethanol and 240 mg of acetic acid, stirred at room temperature, and added 1 mol of sodium nitrite.
Zinc dust 9F (0.26 mol) was added over 20 minutes, followed by zinc powder 5F 16f (0.59 mol) at a liquid temperature of 20 to 55 mol.
It was added over 20 minutes while controlling the temperature. After adding the zinc powder, the mixture was further stirred for 40 minutes, and the precipitated solids and unreacted zinc were separated by furnace.

On the other hand, 37.6f (0,212 mol) of 4-dimethylamino-215-u methylbenzaldehyde was dissolved in 45-methanol, and this solution was added to the above reaction solution while stirring at room temperature to form a large amount of yellow precipitate. Obtained.

After removing the product and drying it, methanol 100m/%MKK15
Recrystallized from a mixed solvent of 0-, m, p, 157-158
37.5 f of yellow crystals were obtained. Yield 45q6 Elemental Analysis Molecule 2 027H27J 81 Calculated Value Chi Analysis 1 Direction Chi 0 82.4 82.5 H6,926,85 N 10.68 10.77 In a preferred embodiment of the present invention, the photosensitive layer is a charge generating layer. A hydrazone compound represented by the general formula (1) can be used as a charge transport material of an electrophotographic photoreceptor which is functionally separated in a charge transport layer.

The charge transport layer according to the present invention can be prepared by dissolving the hydrazone compound represented by the above-mentioned general formula (1) and a binder in a suitable solvent.
It is preferable to form it by applying a diluted solution and drying it. Binders used in particular include, for example, polyarylate resins, polysulfone resins, polyamide resins, acrylic resins, acrylonitrile resins,
Methacrylic resin, vinyl chloride resin, vinyl acetate resin, phenolic resin, epoxy resin, polyester resin, alkyd resin, tJ"recarbonate, polyurethane, or copolymer resin containing two or more repeating units of these resins, such as styrene. Examples include butadiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, etc.In addition to such insulating polymers, organic photoconductive polymers such as polyvinylcarbazole, polyvinylanthracene, and polyvinylpyrene are also used. can.

The blending ratio of the binder and the hydrazone compound is preferably 10 to 500 parts of the hydrazone compound per 100 parts of the binder.

? The charge transport layer is electrically connected to the charge generation layer below, and receives charge carriers injected from the charge generation layer in the presence of an electric field, and transports these charge carriers to the surface. It has the ability to In this case, the charge transport layer may be laminated on or under the charge generation layer (C). However, the charge transport layer may be laminated on the charge generation layer. Since there is a limit to how much charge carriers can be transported in the charge transport layer, it is not possible to make the film thicker than necessary.Generally, the thickness is between 5 microns and 30 microns, but it is preferable. The range is 8 microns to 20 microns.

The organic solvent used when forming such a charge transport layer is
The binder varies depending on the type of binder used, and it is preferable to select one that does not dissolve the charge generation layer or underlying subbing layer. Specific organic solvents include alcohols such as methanol, ethanol, and isopropanol; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; amides such as IJ, N-dimethylformamide, and N,N-dimethylacetamide; ``Sulfoxides such as rusulfoxide, ethers such as tetrahydrofuran, dioxane, and ethylene tallycol monomethyl ether, esters such as methyl acetate and ethyl acetate, and fats such as chloroform, methylene chloride, dichloroethylene, carbon tetrachloride, and trichloroethylene. Group halogenated hydrocarbons, aromatic compounds such as benzene, toluene, xylene, refloin, monochlorobenzene, dichlorobenzene, etc. can be used.

Coating methods include dip coating, spray coating, spinner coating, bead coating,
This can be carried out using a coating method such as a Mayer bar coating method, a Fried coach ink method, a roller coating method, or a curtain coating method. For drying, it is preferable to dry to the touch at room temperature and then heat dry. Heat drying at a temperature of 30°C to 200°C for 5 minutes to 2
It can be carried out stationary or under blown air for a period of time within a range of hours.

The charge transport layer of the present invention can contain various additives. Such additives include diphenyl, salts (
1-'phenyl, 0-ternoeny.

3,5
-dinitrosalicylic acid, various fluorocarbons, and the like.

The charge generation layer used in the present invention includes selenium, selenium-tellurium, pyrylium, thiopyrylium dyes, fucrocyanine pigments, anthinthrone pigments, dibenzpyrenequinone pigments, vilanthrone@Q family, trisazo pigments, and disazo pigments. , azo pigments, -f Fuji 5-Hyakuryo, quinacridone pigments, asymmetric quinocyanine, quinocyanine, or charge-generating substances such as amorphous silicon described in Japanese Patent Application Laid-Open No. 54-L4.145. It is possible to use a resin dispersion layer of m/PJ or Z.

The charge generator tr used in the photoreceptor of the present invention is:
For example, inorganic compounds or organically modified crops shown in 1jC below can be mentioned.

Charge-generating substances (1) Amorphous silicon (2) Selenium-tellurium (3) Selenium-arsenic (4) Cadmium sulfide (5) 0,1,A678000
) (60 thioindigo dye (C, 1,478800) (
61) β-type copper phthalocyanine (62) (67)) (64) (65) The charge-generating layer is prepared by dispersing the charge-generating 1 phthalocyanine of the front and back in a suitable binder and bonding it to the substrate. It can be formed by coating on top of VC, and it can also be obtained by forming a vacuum with a hollow evaporation device N. The binder that can be used when forming the charge generation layer by coating can be selected from a wide range of insulating resins, and organic photoconductive resins such as poly-IJ+N-vinylcarbazole, polyvinylanthracene and polyvinylpyrene, and polyvinyl-IJ. -r- can be selected. Preferably polyvinyl butyral, boria relay
1- (Condensation polymer of bisphenol A and phthalic acid, etc.)
, polycarbonate, polyester, phenoxy resin, polyvinyl acetate, acrylic resin 1, ]? Reacrylamide resin, polyamide, polyvinylpyridine, cellulose resin, urethane resin, epoxy resin, casein,
Examples include insulating resins such as polyvinyl alcohol and polyvinylpyrrolidone. It is suitable that the resin contained in the frost-producing layer has a density of 80 to 80% or less, and 40 to 40% or less. Organic solvents used during coating include alcohols such as methanol, ethanol, and isopropanol, acetone, methylegulketone, and cyclohexane.
Nori such as Suwanon.

amides such as N,N-dimethylformamide and N,N-dimethylacetamide, sulpokinds such as dimethylforphogide, needles such as tetrahydrofuran, dioxane, and ethylene glycol monomethyl ether, methyl acetate, Nisdels such as ethyl acetate, aliphatic compounds such as chloroform, methylene chloride, dichloroethylene, carbon tetrachloride, trichlorethylene, /7/
Hydrocarbons or aromatics such as benzene, toluene, xylene, ligroin, monochlorobenzene, and dichlorobenzene can be used.

Coating should be performed using coating methods such as dip coating, spray coating, spinner coating, heat 1 coating, Mayer bar coating, blade coating, roller coating, cargun coating, etc. I can do it.

(2) The charge generation layer contains as much of the above-mentioned photoconductor as possible in order to obtain sufficient absorbance; 5 microns or less, preferably 0.01 microns to 1
A thin film layer having a thickness of microns is preferable. This means that most of the incident light is absorbed by the charge generation layer, generating many charge carriers, and that the generated charge carriers are not deactivated by recombination or trapping, but are transferred to the charge transport layer. This is due to the need for injection.

A photosensitive layer consisting of such a laminated groove structure of a charge generation layer and a charge transport layer is provided on a substrate having a conductive layer. Guide? [
The substrate having the layer may be one in which the substrate itself is conductive, such as aluminum, aluminum alloy, copper, zinc,
Metals such as stainless steel, vanadium, molybdenum, chromium, titanium, nickel, indium, gold and platinum can be used, and in addition, aluminum, aluminum alloys, indium oxide, tin oxide, indium oxide-tin oxide alloys, etc. can be used by vacuum evaporation. Films with coated layers (e.g., polyegulene, 11-hylypropylene, polyvinyl chloride, polyethylene terephthalate, acrylic resin, J5 fluoroethylene, etc.), conductive, electrically conductive (
'l' particles (e.g. λ-ge, force-r1'-buzik, Kushi Oni-l, etc.) with appropriate pinpoints in Plus Book's ``Second God''] ``Shitano 1 (three bodies, conductive Particles can be incorporated into plastic or paper and used as a 76 substrate or a 471 polymer polymer.

;*, 'rti, barrier function and adhesive IP in the middle of the layer and photosensitive layer! + (jl', i can also provide a subbing layer. lower '71 #t fJl, /J Sein, +I? +) Vinyl alcohol, nitrocellulose, nigerene-acrylic acid copolymer,) 6, Nylon 66, Nylon 610141
Gfn nylon, alcohol dimethyl nylon, etc.)
, polyurethane, gelagoon, aluminum oxide, etc.

The thickness of the undercoat layer is 0.1 to 5 microns, preferably 0.5 to 3 microns.

When using a photoreceptor in which a conductive layer, a charge generation layer, and a charge transport layer are laminated at Iff<, since the hydrazone compound has hole transport properties, it is necessary to make the surface of the charge transport layer a negative band 7. When the band surface is exposed after exposure, the holes generated in the charge generation layer are injected into the charge transport layer in the exposed area, and then reach the surface and neutralize the negative 1π charge, resulting in attenuation of the surface potential and the interaction with the unexposed 1'fli. An electrostatic contrast occurs between them. During development, it is necessary to use a positively charged toner, contrary to the case where an electron transport material is used.

In another embodiment of the present invention, the disazo pigments described above may be used.
Byrylium dyes, thiapyrylium dyes, selenapyrylium dyes, benzobyrylium dyes, benzothiapyrylium dyes disclosed in No. 8, No. 31586500, etc.
Pigments and dyes having photoconductivity such as naphthopyryliuno, dyes, and naphthoderbyryllium dyes can also be used as sensitizers.

Yet, in another embodiment, a eutectic complex of a pyrylium dye and an electrically insulating polymer having an alkylidene diarylene moiety, such as disclosed in US Pat. No. 3,684,502, may be used as the sensitizer. This eutectic complex is, for example, 4
-[4-bis-(2-chloroethyl)aminophenyl)
-2,6-diphenyl diabyrylium perchloride
and poly(4,4'-isozolobylidene diphenylene carbonate) in a haloconated hydrocarbon solvent (e.g.
Dichloromethane, chloroform, tetracarbonized carbon”＜%
1 + 1- ) chloroethane, 1.2-') chloroethane, 11L2- ) +) chloroethane, chlorobenzene, furomobenzene, 1.2-') chlorobenzene), and then dissolved in a non-polar solvent ("Sueha"). It is obtained as a particulate eutectic complex by adding hexano, octane, decane, 2,2,4-)limethylbenzene, and ligroin. , vinyl (0 (fat), vinylidene chloride-acrylonitrile copolymer, styrene-acrylonitrile copolymer, vinyl acedate-vinyl chloride copolymer, Jf
Livinyl Pujiral;1? Limethyl methacrylate 1,
,;l! It may contain N-butyl methacrylate, polyester, cellulose Nisdels, etc. as a binder.

The electrophotographic photoreceptor of the present invention can be widely used in electrophotographic application fields such as laser printers, ORT printers, and Sanko Shin plate-making systems, as well as in electrophotographic J1 (copying machines). .

According to the present invention, it is possible to provide a photoreceptor with a high sensitivity electron beam, and it has the advantage that fluctuations in bright area potential and dark area potential when repeatedly charging and exposing are performed can be made small.

The present invention will be explained below according to examples.

Example 1 β-type copper phthalocyanine (trade name L) manufactured by Toyo Ink Seisaku@
j, onol Bln, e NOB TOllOr)
Sequential flow of brass in water, ethanol, and benzene? 1. It was filtered and diluted. Pigment 7F, DuPont Press [Product Name: Polyester Adhesive Knob 49,000 (same size 20
h) J14r, toluene 357, Geokisuton 35F
were mixed and dispersed in a ball mill for 6 hours to prepare a coating solution FGL+4. This coating liquid was applied onto an aluminum sheet using a Mayer bar to a dry film thickness of 0.5 microns to form a charge generation layer.

Next, the exemplified compound H-(1) is used as the charge transport 1 rostrum.
72 and polycalf 1 inate resin (Teijin Kasei GM3'
IIν product name t'lgunjito K-1300, J
) 79 Tok y-) Stir and dissolve the solution in a mixed solution of 35F of lahydrofuran and 35F of chlorobenzene, and dry the solution with 1 Mayer per second of the previous charge generation layer +16! Coat it to a thickness of 11 microns,
An electrophotographic photoreceptor having a photosensitive layer consisting of a 21-layer structure was prepared.

Created in this way, 7'C electronic copy! (The photoconductor was manufactured by Kawaguchi Denki ('f13JM p+7')
40 If Mo6. el EIP -428 Gold is charged with static corona at -5KV,
After holding for 0 seconds, it was exposed to light at an illuminance of 51uX, and the band m, special ti
Look up t.

As for the charging characteristics, it is necessary to attenuate the surface potential (Vo)'- and the potential (vl) when dark decayed for 1 second to A;')
: The optical surface (E%) was measured at j.

Furthermore, in order to measure the fluctuations in bright area potential and dark area potential during repeated use, the photoreceptor was fabricated in this example.
5.6KV corona charger, exposure hazard 1Q 1ux-se
It was attached to the cylinder of an electrophotographic copying machine equipped with the exposure optical system, developing device, transfer charger, static eliminating silk light optical system, and creeboo of (a).

This copying machine is configured to print an image on transfer paper as a cylinder is driven. Using this machine, the initial light potential (V+7) and dark potential (Mo) and the bright potential (Vt) and dark potential (VD) of Sakae after 5000 uses were measured. The results are shown below.

Vn knee 570 volts Vl: -555 bold JI'34: 5.21ux sea first
VD after 000 endurance: 645
d! Ruto "L: 70dE Ruto VD knee 63
5 Bok Kano vL knee 70 volts'P 1 row 2~1
4 In each of the Examples, the Exemplary Compound H-(
Example compound t(-(2), H-(3), H
-(4), H-(5), I(-(6), n-(ha,
H-(8), H-(9), H-(10), H-(
10, l(-θ force, H-(1:I%H-(1,11) was used, but a 1"1" photoreceptor was prepared by the same method as in Example 1.

The electronic 1'cl performance of each photoreceptor was measured in the same manner as in Example 1. The results of this h are shown below.

2 5.8 -550 -ri403,
5.4 -565 -5
604 Otsu 3 580 5
705:1565-565 6 4.8 ~555 -5507
5.5 -565 -55586.6
575 5559 4.0 -5
60 -54510 5.4
-570 -565i1
4.9 -550 -535
12 4.7 570
--5551 Ro
Ro, 3-545
-52514 6.9
550 5252
-635 -75 -630
-753 -625 -65 -62
5 -754 -650 -95
-640-1055 645 90
635 1006 635
60 650 757
-645 -75 -630 -80
8 -655 -90 -650
-959 -635 -45 -6
30 -6010 660 85
-645 9011 -625
-50 -615 -6012 ~6
45 -70 635 7513
-615 -25 -600
-4014 -6ro O-40-615-60 Example
15 4-(4-dimebru-7minophenyl)-2,6-diphenylpoor avirylium perchloride 1-32 and the above-mentioned exemplified human>sin compound H-fl ]0; Toluene (50)-dimequinane (50) solution (manufactured by DuPont) was combined with 100 me K?
I had 11 girls for uJ. This dispersion was coated on an aluminum sheet with one gamma ear to give a dry film thickness of 15 microns.

One piece of the photoreceptor prepared in this manner was measured for photoresistance and photoresistance in the same manner as in Example 1J-1rsJ. The results are shown below.

Gro: -560 volts VIA-555 volts Eg(:　　　　　　5.Q　　　1lXI[]e.

Initial VD' 6ZQd Gault Vl, knee 75 volts 5 (j O01"1 lil Ht long time'v: 660 volts vI2 2 -75! l Rut Example J aqueous solution of casein on aluminum plate (casein 1
t'), r, 28° ammonia water 1f.

Apply 222 m/) of water with a Mayer bar and dry to a film thickness of 1
A 1 chrome adhesive layer was formed.

Next, 5v of a disazo pigment having the following structure and 2v of butyral resin (butyralization degree 66 mol) were dissolved in 95m/VC of ethanol and dispersed together with a medicinal liquid, and then coated on the adhesive layer so that the film thickness after drying was 0. A 1YL charge generation layer having a thickness of 4 microns was formed.

Next, the exemplified human dicine compound)(-(4)
52 and poly-4,4'-dioxydiphenyl-2,2''
Propane carbonate (viscosity average molecular weight 30,000)
An electrophotographic photoreceptor was prepared by applying a solution of 5y' (IT dissolved in 150 me of dichloromethane) onto the charge generation layer and drying to form a charge transport layer having a thickness of 11 microns.

Electrophotograph 7F of the electrophotographic photoreceptor prepared in this way)
The properties were measured in the same manner as in Example 1.

The results are shown below.

VO knee sso volt Vj: -570 volt E3 (: 5.51uxleaa initial Vl): -67Qdh t VL:
-65 volts after 5000 cycles vI): -660 volts VL: -75 volts Example 17 0.21 thickness molybdenum plate (substrate) with a cleaned surface
was fixed at a predetermined position in a glow discharge deposition tank. Next, the inside of the tank was evacuated to a pressure of about 5 x 1 [] torr. Thereafter, the input i and pressure of the heater were increased to stabilize the molybdenum substrate temperature at 150°C. After that, hydrogen gas and silane gas (15 volumes of hydrogen gas) were introduced into the tank, and the gas flow seal and the main valve of the evaporation tank were adjusted.
orr Ic was stabilized. Next, add 5 MH2 to the induction coil.
High frequency power was applied to generate a glow discharge inside the coil in the tank, resulting in an input power of 30W. An amorphous silicon film is grown on the substrate under the above conditions to a film thickness of 2n.
After maintaining the same condition, I set the glow discharge to medium+b. After that, the heating heater and high-frequency IJ source are turned off, and after waiting for the substrate temperature to reach 100°C (C), the hydrogen gas and silane gas outflow valves are closed, and the inside of the tank is temporarily adjusted to 1[1-5 torr.
After applying Icl, the pressure was returned to atmospheric pressure and the substrate was taken out.

Then, on this amorphous silicon layer, do exactly the same as in Example 1. A. Cargo transportation R1 was formed.

The thus obtained photoreceptor was charged by placing it in a light experiment apparatus for 1 hour, and was then corona charged at 6 KV and irradiated with 1 light.

The light image is passed through a tungsten lamp light (transmission type gas using 1,1) char 1 j! was shot at.

Immediately thereafter, a charged developer (containing toner and carrier) was cascaded onto the surface of the photoreceptor, and a good toner image was obtained on the surface of the photoreceptor.

Example 18 4-(4-dimebulaminophenyl)-2,6-:
, 5 phenylthiapyrylium verchlorate 52 and yl
After fully dissolving 5v of r +7 (4,4'-isozolopylidene diphenylene carbonate) in 200m6 of dichloromethane, toluene j00m/ was added to precipitate a eutectic complex. After this precipitate was taken from house to house, dichloromethane was added to redissolve it, and then this solution was added with 10 ml of n-hexane.
0m/! A precipitate of the eutectic complex was obtained by adding 95r+LIC of methanol solution containing polyvinyl butyral 22 to this eutectic complex 51, and dispersed in a Pall mill for 6 hours. A charge generation layer was formed by applying the solution of the molecule jJ on an aluminum plate having a layer of 01742 using a Meyer parser so that the thickness after drying was 0.4 microns.

Then, on top of this layer, % of the material used in Example 1 was added.
It also forms a covering layer similar to the cargo transport layer.

The electronic stability of the photoreceptor thus prepared was measured in the same manner as in Example 1. The results are shown below.

Va: -5/) 5 volts Vj: -545 volts 11, +4: 3.31ux-ee.

Initial VD knee 615 volts VL Knee 4O volts VD after 5000 cycles of endurance: -605 volts vL Knee 55 volts Example 19 A eutectic complex similar to the eutectic complex used in Example 18 52 and the hydrazone compound H-(4 ) was added to 150 m/! of polyester (Polyester Adhesive 49000: DuPont Co., Ltd. 12!!) of tetrahydrofuran solution and thoroughly mixed and stirred. The film thickness after drying this solution on an aluminum sheet using a Meyer bar trap was It was applied so that the thickness was 15 microns.

The electronic X-characteristics of this photoreceptor were measured in the same manner as in Example 1. The results are shown below.

Vo: -550 volts V: -535 volts K) (: 3.7 luxTgea first period vD knee 630 volts VL: -40 volts After 5000 times durability vD knee 615 volts VL: -55 volts Patent applicant: Canon Co., Ltd. Representative Patent Attorney Yu Kano

Claims (1)

[Scope of Claims] An electrophotographic photoreceptor comprising a layer containing a hydrazone compound represented by the following general formula (1). In the general formula, R1 and R2 are an alkyl group which may have a substituent, an aral 4' group, a phenyl group, and 5 to
Residues forming a 6-membered ring are indicated by R,. shows. Further, n indicates an integer between 0 and 1.