JPS62244060A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain the titled body which is lessened a change of between a potential at a light part and that at a dark part after charging and exposing the titled body repeatedly and has good sensitivity by incorporating a specific low molecular weight org. compd. as an electrostatic charge transfer substance to the titled body. CONSTITUTION:The titled body comprises the layer contg. a hydrazone compd. shown by the formula wherein R1 is a naphthyl group which may be substd. R2 is an alkyl, an aralkyl or an aryl group which may be substd. R3 is hydrogen atom, an alkyl or an alkoxy group or halogen atom, at least one or both of Ar1 and Ar2 are each an aryl group having one or more of donor type substituents. The electrostatic charge transfer layer is preferably formed by coating the solution which is dissolved a compd. shown by the formula and a binding agent in a suitable solvent, followed by drying it. Thus, the titled body having high sensitivity is obtd. The change of between the potential at the light part and that at the dark part is lessened at the time of charging and exposing the titled body repeatedly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having a low molecular weight organic photoconductor that provides improved electrophotographic properties. be.

[Conventional technology]

Conventionally, inorganic photoconductive materials such as selenium, cadmium sulfide, and zinc oxide are known as photoconductive materials used in electrophotographic photoreceptors. These photoconductive materials have many advantages, such as being able to be charged to an appropriate potential in the dark, having little charge dissipation in the dark, or quickly dissipating the charge when irradiated with light. On the other hand, it has various drawbacks. For example, selenium-based photoreceptors easily crystallize due to factors such as temperature, humidity, dust, and pressure.
In particular, when the ambient temperature exceeds 40° C., there are disadvantages such as significant crystallization, a decrease in chargeability, and the appearance of white spots on images. Cadmium sulfide photoreceptors do not provide stable sensitivity in humid environments, and zinc-brothed 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 remers including polyvinylcarbazole have been proposed;
Although +7mer is superior in terms of film formability and light weight compared to the aforementioned inorganic photoconductive materials, it has been difficult to put it into practical use until now because it still lacks sufficient film formability. This is because they are inferior to inorganic photoconductive materials in terms of sensitivity, durability, and stability against environmental changes. In addition, hydrazone compounds disclosed in U.S. Pat. No. 415091'17, triarylpyrazoline compounds disclosed in U.S. Pat. Low-molecular organic photoconductors such as the 9-styrylanthracene compound described in et al. have been proposed. Such low-molecular organic photoconductors can be made to have organic photoconductivity by appropriately selecting the binder used. Although it has become possible to overcome the drawbacks of film formability that had been a problem in the field of remers, 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. Electrophotographic photoreceptors using this laminated structure as a photosensitive layer can now be improved in terms of sensitivity to visible light, charge retention, surface strength, etc. Such electrophotographic photoreceptors are disclosed, for example, in US Pat. No. 3,837,851 and US Pat. No. 3,871,882.

However, electrophotographic photoreceptors that use conventional low-molecular organic photoconductors in the charge transport layer do not always have sufficient sensitivity and characteristics, especially when repeatedly charged and exposed. There is a point that needs to be greatly improved in terms of fluctuations in bright area potential and dark area potential.

[Problem that the invention seeks to solve]

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 a new organic photoconductor.

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.

[Means for solving problems]

That is, the present invention is an electrophotographic photoreceptor characterized by having a layer containing a hydrazone compound represented by the following general formula (1).

General formula: In the formula, R1 is a naphthyl group, R2 is an alkyl group such as methyl, ethyl, propyl, butyl, an aralkyl group such as benzyl, 7-enethyl, naphthylmethyl, or a phenyl, naphthyl, anthryl, fluorenyl group, etc. Indicates an aryl group. The above-mentioned 7-tyl group, alkyl group, aralkyl group, and aryl group include alkyl groups such as methyl, ethyl, propyl, and butyl, alkoxy groups such as methoxy, ethoxy, and propoxy, halogen atoms such as fluorine, chlorine, bromine, and iodine, Alternatively, it may be substituted with a substituted amino group such as dimethylamino, diethylamino, or diphenylamino. R3 represents a hydrogen atom, an alkyl group such as methyl, ethyl, propyl, butyl, an alkoxy group such as methoxy, ethoxy, butoxy, or a yy atom such as fluorine, chlorine, bromine, iodine, etc.

Ar, l Ar2 represents an aryl group such as phenyl, naphthyl, or fluorenyl, in which one or both of them have one or more donor substituents, but the donor substituents include alkyl groups such as methyl, ethyl, propyl, butyl, etc. groups, alkoxy groups such as methoxy, ethoxy, propoxy, butoxy, substituted amine groups such as dimethylamino, diethylamino, diphenylamino, pyrrolidino, morpholino, etc.
A hydroxyl group, a thiol group, or an alkylthio group such as methylthio, ethylthio, propylthio, etc. is used.

The present inventors have made earnest efforts to improve the electrophotographic properties of hydrazone compounds. As a result, Ar in general formula (1)
If 1+Ar2 is alkyl, it shows good characteristics in terms of sensitivity, or in terms of durability stability, there are defects with particularly large potential fluctuations.If Ar1+Ar2 is aryl, durability stability is good, but Due to the fact that the sensitivity is insufficient, we assumed that the problem could be solved by introducing a donor substituent to the aryl group to promote charge flow, and the present invention was developed based on this assumption. It is. By making it easier for charge to flow in the molecules of the charge transport substance, cation radicals are generated and less likely to move, and as a result of increasing the ionization potential by introducing an aryl-substituted amino group, stability is also improved. It is thought that the

Representative examples of the compound represented by general formula (1) are listed below.

Compound example Next, a synthesis example of the above compound will be shown.

Synthesis Example 1 (Synthesis of the exemplified hydrazone compound (2)) 120 ethanol in a 500 rIL three-necked flask
RI! ! , acetic acid 120d, α-phenyl, -α-(α-
8.49 g (0,036 mol) of naphthyl)hydrazine,
4.41-Dimethoxyphenylaminobenzaldehyde 12. OOg (0,036 mol) was added, stirred at room temperature for 1 hour, and poured into water. Next, the obtained solid content was filtered and washed with water repeatedly, and the solid content was dried using F.

Reconsolidation from the methyl ethyl ketone/ethanol mixed disintegration system yielded pale yellow crystals 10.29.9.

(Yield 52%) Calculated elemental analysis value Analysis value C80,85-80,92% H5,68% 5.77thN 7.64th 7.62%Aldehyde shown by It can be synthesized in the same manner as in Synthesis Example 1 using.

In a preferred embodiment of the present invention, a compound represented by the above general formula (R) can be used as a charge transport material of an electrophotographic photoreceptor in which the photosensitive layer is functionally separated into a charge generation layer and a charge transport layer.

The charge transport layer according to the present invention is preferably formed by applying a solution prepared by dissolving the compound represented by the general formula (1) and a binder in a suitable solvent and drying the solution. Examples of the binder used here include polyarylate resin, polysulfone resin, polyamide resin, acrylic resin, acrylonitrile resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, phenol resin, epoxy resin, polyester resin, alkyd resin, and polycarbonate resin. Polyurethane, polyurethane, or copolymer resins containing two or more repeating units of these resins, such as styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, and the like.

In addition to such insulating polymers, organic photoconductive polymers such as vinylcarbazole, polyvinylanthracene, and polyvinylpyrene can also be used.

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

The charge transport layer is electrically connected to the underlying charge generation layer, and has the function of receiving and taking charge carriers injected from the charge generation layer in the presence of an electric field and transporting these charge carriers to the surface. have. At this time, this charge transport layer may be laminated on or under the charge generation layer. However, it is desirable that the charge transport layer is laminated on the charge generation layer.

Since this charge transport layer has a limit in its ability to transport charge carriers, it cannot be made thicker than necessary. Typically it is 5 microns to 30 microns, with a preferred range of 8 microns to 20 microns.

The organic solvent used when forming such a charge transport layer is
The binder may vary depending on the type of binder used, or it is preferable to select one that dissolves the charge generation layer and underlying subbing layer. Specific organic solvents include alcohols such as methanol, ethanol, and isozolo I4mer, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide. sulfoxides such as, tetrahydro7rane, dioxane, ethers such as ethylene glycol monomethyl ether, esters such as methyl acetate, ethyl acetate,
Aliphatic halogenated hydrocarbons such as chloroform, methylene chloride, dichloroethylene, carbon tetrachloride, trichloroethylene, etc., or aromatics such as benzene, toluene, xylene, ligroin, monochlorobenzene, dichlorobenzene, etc. can be used. .

Coating methods include dip coating method, spray coating method, spinner coating method, peed coating method,
This can be done using a coating method such as a Mayer coating method, a blade coating 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, u:yenyl chloride, 0-terphenyl, p-terphenyl,
dibutyl phthalate, dimethyl glycol phthalate,
Examples include dioctyl phthalate, triphenyl phosphoric acid, methylnaphthalene, benzophenone, chlorinated noraphine, dilauryl thioglopionate, 3,5-dinitrosalicylic acid, and various fluorocardans.

The charge generation layer used in the present invention includes selenium, selenium-tellurium, pyrylium, thiovirilicum, azulenium dyes,
7 Talocyanine pigments, andanthrone pigments, dibenzpyrenequinone pigments, pyranthrone pigments, trisazo pigments, disazo pigments, azo pigments, in-novo pigments, quinacridone pigments, thiacyanine, asymmetric quinocyanine, quinocyanine, or in JP-A-54-143645 Separate deposited layers or resin dispersion layers selected from charge generating materials such as amorphous silicon as described can be used.

Examples of the charge generating substance used in the electrophotographic photoreceptor of the present invention include the following inorganic compounds and organic compounds.

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- The charge-generating layer can be formed by dispersing the charge-generating substance described above in a suitable binder and coating it on the substrate, or by forming a film deposited using a vacuum evaporation device. Obtainable. Binders that can be used to form the charge generating layer by coating can be selected from a wide variety of insulating resins, and can also be selected from organic photoconductive polymers such as poly-N-pinylcarnosol, polyvinylanthracene, and polyvinylpyrene. .

Preferably,? Lipinylputyral, I realylate (
polycarbonate, polyester, phenoxy resin, polyvinyl acetate, acrylic resin, polyacrylamide resin, etc.) Liamide, polyvinylpyridine, cellulose resin, urethane resin, epoxy resin, casein, ? Examples include insulating resins such as ribinyl alcohol and polyvinylpyrrolidone. The resin contained in the charge generation layer is suitably 80% by weight or less, preferably 40% by weight or less. Organic solvents used during coating include alcohols such as methanol, ethanol, and isoglobin, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, and amides such as N,N-trimethylformamide and N,N-dimethylacetamide. , sulfoxides such as dimethyl sulfoxide, ethers such as tetrahydrofuran, dioxane, and ethylene glycol monomethyl ether, esters such as methyl acetate and ethyl acetate, and aliphatics such as chloroform, methylene chloride, dichloroethylene, carbon tetrachloride, and trichloroethylene. Halogenated hydrocarbons or aromatics such as benzene, toluene, xylene, ligroin, monochlorobenzene, dichlorobenzene, etc. can be used.

Coating can be done by dip coating method, spray coating method, spinner coating method, beat coating method,
Coating methods such as the Mayer coating method, blade coating method, roller coating method, and curtain coating method can be used.

The charge generation layer contains as much of the organic photoconductor as possible in order to obtain sufficient absorbance and is preferably a thin film layer, for example less than 5 microns, in order to shorten the range of the generated charge carriers. is preferably a thin film layer having a thickness of 0.01 micron to 1 micron. 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 having such a laminated structure of a charge generation layer and a charge transport layer is provided on a substrate having a conductive layer. Examples of substrates having a conductive layer include those in which the substrate itself is conductive;
For example, aluminum, aluminum alloy, copper, zinc, stainless steel, vanadium, molybdenum, chromium, titanium,
Glass materials (e.g. , polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, acrylic resin, fluorinated ethylene, etc.), conductive particles (e.g., aluminum powder, titanium oxide, tin oxide, zinc oxide, carbon black, silver particles, etc.). A substrate coated on plastic or the above-mentioned conductive substrate together with a binder, a substrate made of glass or paper impregnated with conductive particles, a glass stick having a conductive primer, etc. can be used.

A subbing layer having barrier and adhesive functions can also be provided between the conductive layer and the photosensitive layer. Subbing layer, casein,
Polyvinyl alcohol, nitrocellulose, ethylene-
It can be formed from acrylic acid copolymer, polyamide (nylon 6, nylon 66, nylon 610, copolymerized nylon, alkoxymethylated nylon, etc.), polyurethane, gelatin, aluminum oxide, and the like.

The thickness of the undercoat layer is suitably 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 in this order, the hydrazone compound has hole transport properties, so the surface of the charge transport layer must be negatively charged, and when exposed to light after charging, In the exposed area, holes generated in the charge generation layer are injected into the charge transport layer, and then reach the surface to neutralize the negative charges, resulting in attenuation of the surface potential and an electrostatic contrast between the layer and the unexposed area. During development, it is necessary to use a positively charged toner, contrary to the case where an electron transport material is used.

In another specific example of the present invention, the above-mentioned nosazo pigment or the pyrylium dyes, thiapyrylium dyes, selenapyrylium dyes, penzopyrylicum dyes, and benzopyrillium dyes disclosed in U.S. Pat. No. 3,554,745, U.S. Pat. Photoconductive pigments and dyes such as thiapyrylium dyes, naphthopyryllium dyes, and naphthothiapyrylium dyes can also be used as sensitizers.

In another specific example, a eutectic complex of a pyrylium dye and an electrically insulating polymer having an alkylidene diarylene moiety, as disclosed in US Pat. No. 3,684,502, can also be used as a sensitizer. This eutectic complex is, for example, 4
-[4-bis-(2-chloroethyl)amino-7'enyl) -2,6-diphenylthiapyrylium verchlorate and poly(4,4'' ingropylidene diphenylene carbonate) hydrogenated hydrocarbon System solvents (e.g. dichloromethane, chloroform, carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, 1.1.2-
) dichloroethane, chlorobenzene, bromopenze/,
1,2-dichlorobenzene) and then dissolved in a non-polar solvent (e.g. hethane, octane, decane, 2,2-dichlorobenzene).
．． A particulate eutectic complex is obtained by adding 4-trimethylbenzene and ligroin. The electrophotographic photoreceptor in this specific example includes styrene-ptazoene copolymer, silicone resin, vinyl resin, vinylidene chloride-acrylonitrile copolymer, styrene-acrylonitrile copolymer, vinyl acetate-vinyl chloride copolymer, polyvinyl butyral, ? Limethyl methacrylate, poly-N-butyl methacrylate, polyesters,
Cellulose esters and the like can be contained as a binder.

The electrophotographic photoreceptor of the present invention can be used not only for electrophotographic copying machines, but also for laser grinters, CRT printers,
It can also be widely used in electrophotographic application fields such as electrophotographic plate making systems.

According to the present invention, it is possible to provide a highly sensitive electrophotographic photoreceptor, and it has the advantage that fluctuations in bright area potential and dark area potential are small when repeated charging and exposure are performed.

Hereinafter, the present invention will be explained according to examples.

Example 1 Pigment 711, which was purified by filtering and refluxing Beta group 7 talocyanine (trade name Llonol Btu@NCB Tonsr) manufactured by Toyo Ink Mfg. Co., Ltd. in water, ethanol and benzene; DeS Bon Co., Ltd. [Product name: Polyester Adhesive 49,000 (solid content 20%) J1]
4, f:) A coating solution was prepared by mixing 35 I of toluene and 35.9 I of dioxane and dispersing the mixture in a gall mill for 6 hours. This coating solution was coated onto an aluminum sheet using a Meyer perforator to give a dry film thickness of 0.5 microns to form a charge generation layer.

Next, as a charge transport compound, the above-mentioned exemplified compound M (2) was mixed with 79, polycarbonate resin (trade name "Noyan Light ni-1300" manufactured by Ondai Kasei Co., Ltd.) 711, tetrahydro 7rane 35I and chlorobenzene. The solution obtained by stirring and dissolving in 35 g of a mixed solvent was coated on the charge generation layer using a Mayer Parr so that the dry film thickness was 16 microns to form a photosensitive layer with a two-layer structure. An electrophotographic photoreceptor was created.

The electrophotographic photoreceptor thus prepared was statically charged with corona at 15 kV using an electrostatic copying paper tester (Model 1-8P-428 manufactured by Kawaguchi Electric Co., Ltd.) and held in a dark place for 1 second. Thereafter, it was exposed to light at an illuminance of 25 Lux to examine its charging characteristics.

The charging characteristics include the surface potential (vo) and the amount of light exposure required to attenuate the potential (V,) when dark decaying for 1 second (V,).
~) was measured.

Furthermore, in order to measure the fluctuations in bright area potential and dark area potential when used repeatedly, the photoreceptor prepared in this example was attached to the photosensitive drum cylinder of a ppc copier NP-150z manufactured by Canon Inc. I added more copies and made 500 copies as a spare material. Bright area potential (vL) at the initial stage and after copying 5oooo sheets
and changes in dark potential (VD) were measured.

In addition, in place of the above-mentioned exemplified compounds, human 2-sine compounds having the following three structural formulas were used, and in exactly the same manner,
Comparative samples -1, -2 and -3 were prepared and measured in the same manner.

The results are shown below.

Table 1 This result also shows that the compounds of the present invention are partially affected by crystal precipitation.
It can be seen that this compound is extremely superior in terms of sensitivity, durability, and stability compared to the compound used in Example 2.

In each of Examples 2 to 1, Exemplified Compound (1) was used instead of Exemplified Compound (2) as the charge transport compound used in Example 1.
), (3), (5), (7), (8)
, (9) , (lη, on , (L′I).

4. An electrophotographic photoreceptor was prepared in the same manner as in Example 1, except that 翰, (2υ, Q邊1(2!j, (to)) was used, and the pigment shown in the example was used as the charge-generating substance. Created.

The electrophotographic properties of each photoreceptor were measured in the same manner as in Example 1. The results are shown below.

Example after initial 50,000 sheets durability v
, (-*y to) vL (-sx to) vD (-sy to)
vL(-sxt) Example 17 An ammonia aqueous solution of casein (casein 11.2F, 28% ammonia water 1y, water 22.21Ll) was coated on an aluminum cylinder by dip coating method, and dried to a coating amount of 1 ．． o A subbing layer of tp7rl was formed.

Next, 1 part by weight of the charge generating substance of Example 481, 1 part by weight of Zotyral resin (S-LEC BM-2, manufactured by Sekisui Chemical Co., Ltd.) and 30 parts by weight of isopropyl alcohol were added. -Dispersed for 4 hours using a Lumil disperser. This dispersion was first formed and coated on top of the nine sublayers by dip coating, and dried to form a charge generation layer.

The film thickness at this time was 0.3 microns.

Next, 1 part by weight of the exemplified hydrazone compound A (4),
1 part by weight of polysulfone resin (P 1700, manufactured by Union Carbide) and 6 parts by weight of monochlorobenzene were mixed and dissolved by stirring with a stirrer. This liquid was applied onto the charge generation layer by dip coating and dried to form a charge transport layer. The film thickness at this time was 18 microns.

A corona discharge of 15 kV was applied to the photoreceptor thus prepared. The surface potential at this time was measured (initial potential V). Furthermore, the surface potential attenuation was measured after this photoreceptor was left in a dark place for 5 seconds. Sensitivity is determined by setting the potential vK after dark decay to 1
Evaluation was made by measuring the exposure i (E% microziel/32) required for attenuation to /2. At this time, a ternary semiconductor radar of gallium/aluminum/arsenic (output: 5 mW, oscillation wavelength: 780 nm) was used as a light source.

These results were as follows.

V: -650a1? Root potential retention rate = 93% E3A: Q, 7-r microjoules/cm2
Next is the radar beam printer (a reversal development type electrophotographic printer equipped with the same semiconductor laser as above).
The above photoreceptor was attached to LBP-CX (manufactured by Canon).
An actual image forming test was conducted using the photoreceptor as a replacement. The conditions are as follows.

Surface potential knee after primary charging 700V, surface potential knee after image exposure 150V (exposure amount 1μJ/ctR2), transfer potential: +700V, developer polarity: negative polarity, process speed: 50 w/see, development conditions (development bias ) knee 450V, image exposure scan method; image scan, -
Exposure before next charging: 50 Lux, tree full red exposure Image formation was carried out by line scanning a laser beam according to character signals and image signals, and good prints were obtained for both characters and images.

Example 18 4-(4-dimethylaminophenyl)-2,6-cyphenylthiapyrylium chlorate 3.9 and the above-mentioned hydrazone compound 51 were mixed into polyester (Polyester Adhesive 49000: DeS/N) Co., Ltd.) was mixed with toluene 6[-dioxane (51 solution IQQmJ) and dispersed in a Gill mill for 6 hours. This dispersion was coated on an aluminum sheet with a Mayer parr so that the film thickness after drying was 15 microns. did.

Example 1 The electrophotographic characteristics of the photoreceptor produced in this way
It was measured in the same manner as. The results are shown below.

Vo: -595 is Ruto Vl: -5so Delt E5A: 2.0 Lux, see initial VD Knee 69 (l Ruto ■L 2 -110? Ruto 5oooo VD after endurance: -650 & Ruto ■L 2 -150 gelt Example 19 Ammonia aqueous solution of casein (casein 1
1.2.9.28% ammonia water (1 g, water 222 m) was applied using a Mayer Par and dried to form an adhesive layer with a thickness of 1 micron.

Next, disazo pigment 51 having the following structure and 2I butyral resin (degree of butyralization 63 mol) were mixed with ethanol 9
After being dispersed with a liquid dissolved in 5rnt, the charge generating layer was coated on the adhesive layer to form a charge generation layer having a dry film thickness of 0.4 microns.

Next, the above-mentioned hydrazone compound (6) was mixed with 59 and poly-4,4'-dioxydiphenyl-2,2-globunker? An electrophotographic photoreceptor was prepared by applying a solution prepared by dissolving 5 # of Nate (viscosity average molecular weight: 30,000) in 150 d of dichloromethane onto the charge generation layer and drying to form a charge transport layer with a thickness of 14 microns. .

The electrophotographic properties of the electrophotographic photoreceptor thus prepared were measured in the same manner as in Example 1.

The results are shown below.

Vo knee 570 gelt Vl: -555 delt"M: 1.20 tux, see initial VD knee 650 gelt VL: -60 & bolt after 50,000 sheets durability VD: -605 volt VL 2 -95 delt Example 20 Surface cleaned 0.2mm thick molybdenum plate (substrate)
was fixed at a predetermined position in a glow discharge deposition tank. Next, the inside of the tank was evacuated to a vacuum level of about 5 x 10-' torr. Thereafter, the input voltage of the heater was increased to stabilize the molybdenum substrate temperature at 150°C. After that, hydrogen gas and silane gas (15% by volume relative to hydrogen gas) were introduced into the tank, and the gas flow rate and the main pulp of the evaporation tank were adjusted to 0.5 torr.
stabilized at r. Next, 5 MHz high frequency power was applied to the induction coil to generate glow discharge inside the coil in the tank, resulting in an input power of 30 W. An amorphous silicon film was grown on the substrate under the above conditions, and the same conditions were maintained until the film thickness reached 2 μm, after which glow discharge was discontinued. After that, turn off the heating heater and high frequency power supply, wait for the substrate temperature to reach 100°C, close the outflow pulp for hydrogen gas and silane gas, and once the inside of the tank is lowered to 10 torr or less, return the substrate to atmospheric pressure. I took it out.

Next, on this amorphous silicon layer, the exemplified compound l6 (Example 1 except that J3 was used) was applied as a charge transport compound.
A charge transport layer was formed in exactly the same manner as described above.

The photoreceptor thus obtained was installed in a charging exposure experimental device.
It was corona charged at 6 kV and immediately irradiated with a light image. The light image was illuminated through a transmission test chart using a tungsten lung light source. Immediately thereafter, use a charged developer (
A good toner image was obtained on the photoreceptor surface by cascading the toner (containing toner and carrier) onto the photoreceptor surface.

Example 21 4-(4-dimethylaminophenyl)-2,6-diphenylthiapyrylium/Guichiri Loley) 311 and poly(
4,4'-Isoglopylidene diphenylene car? After fully dissolving 3I (Nate) 3I in 200 ml of dichloromethane, 100 ml of toluene was added to precipitate the eutectic complex. After this precipitate was taken from house to house, it was redissolved in dichloromethane, and then 100 d of n-hexane was added to this solution to obtain a precipitate of a eutectic complex.

The eutectic complex 59 with polyvinyl butyral 29 was added to 95 mj of a methanol solution containing polyvinyl butyral 29, and dispersed at 1 lumen for 6 hours. This dispersion was coated onto an aluminum plate having a casein layer using a Mayer par so that the film thickness after drying was 0.4 microns to form a charge generation layer.

Next, a cover layer of a charge transport layer was formed on this charge generation layer in exactly the same manner as in Example 1 except that the exemplified compound was used.

The electrophotographic properties of the photoreceptor thus prepared were measured in the same manner as in Example 1. The results are shown below.

Vo: -600 volts V, : -590yr Ruto E3A: 2.5 tux, s@e Initial VD: -690 volts VL: -450/Ruto 5oooo sheets VD after endurance knee 650 & Ruto VL = -185 Gert Example 22 implementation The same eutectic complex 511 used in Example 21 and the above-mentioned hydrazone compound Jf6@59 were combined with polyester (
The mixture was added to 1 soy of a tetrahydro 7 run solution (Polyester Adhyzip 49000 (manufactured by Devon)) and thoroughly mixed and stirred. This solution was applied onto an aluminum sheet so that the film thickness after drying with Mayer par sieve was 15 μm.

The electrophotographic properties of this photoreceptor were measured in the same manner as in Example 1. The results are shown below.

Vo: -590 is Ruto V, Knee 575 Melt E%: 2.1 tux, sec Initial VD: -680yjf Ruto VL 2 -110731 #Ruto 5oooo sheets VN: 645 & Ruto VL Knee 145 gelt [Effects of the invention] That's all As is clear from the above, according to the present invention, by using a specific low-molecular-weight organic compound as a charge transporting substance, fluctuations in bright area potential and dark area potential after repeated charging exposure are small, and excellent electrophotographic characteristics with good sensitivity are achieved. An electrophotographic photoreceptor can be provided.

Agent Patent Attorney Sekihei Yamashita

Claims (2)

[Claims] (1) An electrophotographic photoreceptor characterized by having a layer containing a hydrazone compound represented by the following general formula (I). General formula: ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R_1 represents an optionally substituted naphthyl group, and R_2 represents an optionally substituted alkyl group, aralkyl group, or aryl group. (R_3 represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom. Ar_1, Ar_2 represents an aryl group in which one or both of them has one or more donor substituents.) (2) Claim 1, wherein the donor substituent is one or more substituents selected from the group consisting of an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a thiol group, and an alkylthio group. electrophotographic photoreceptor.