JPS6115147A - Photoconductive film and electrophotographic sensitive body using it - Google Patents

Abstract

PURPOSE:To enhance sensitivity to rays in a long wavelength region by using a photoconductive film contg. a specified azulenium salt compd. for a photosensitive body. CONSTITUTION:The photosensitive body uses the photoconductive film contg. an azulenium salt compd. represented by the formula in which each of R1-R7 is H, halogen, or a univalent org. residue, and at least one combination of R1 and R2, R2 and R3, R3 and R4, R4 and R5, R5 and R6, and R6 and R7 may form a condensed ring; R8 and R9 are each alkyl, aryl, or aralkyl, or each may form a ring together with N; each of Ar1 and Ar2 is arylene; and Z<-1> is an anion. Such a compd. is applied to, e.g., a conductive substrate by the vacuum deposition method or by dispersing it into a binder and coating with this dispersion, or the like method, and the use of such as azulenium salt compd. for the photosensitive body permits electrophotographic characteristics high in sensitivity to be obtd., especially, to laser beams having oscillated wavelengths in the longer wavelength region.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a novel photoconductive coating and a highly sensitive N1 photoreceptor using the same.

BACKGROUND OF THE INVENTION Pigments and dyes used in photoconductive coatings have been published in numerous publications.

For example, “RCA Revi+, w” Vot, 23
.

In P. 413 to P. 419 (1962, 9), a presentation was made on the photoconductivity of phthalocyanine pigments.
Further, electrophotographic photoreceptors using this phthalocyanine pigment are disclosed in US Pat. No. 3,397,086 and US Pat. No. 3,8161.
This is shown in Publication No. 18, etc. In addition, as an organic semiconductor used for the electronic harp T4 photoreceptor, for example, US Pat.
No. 315983, U.S. Patent No. 4327169 and “Reaeach Disctosure” 205
17 (1981, 5), methine squaric acid dyes shown in U.S. Pat. No. 3,824,099, and U.S. Pat. No. 3,898,084.
Examples include disazo pigments disclosed in US Pat. No. 4,251,613 and the like.

Such organic semiconductors are easier to synthesize than inorganic semiconductors, and can be synthesized as compounds that have photoconductivity for light in the required wavelength range. An electrophotographic photoreceptor formed on a conductive support has the advantage of improved color sensitivity, but only a few of them are practical in terms of sensitivity and durability.

In particular, with the development of low-power semiconductor lasers in recent years,
The development of organic semiconductors with high sensitivity to long wavelength light (nm or more) is becoming active, but compounds with a large extinction coefficient for long wavelength light are generally sensitive to heat and other factors. They are often unstable and have problems such as being easily decomposed by a slight temperature rise, making it substantially difficult to manufacture infrared-sensitive electrophotographic photoreceptors.

Problems to be Solved by the Invention Accordingly, a first object of the present invention is to provide a novel organic semiconductor.

A second object of the present invention is to provide a photoconductive film made of a novel organic semiconductor.

A third object of the present invention is to provide an electrophotographic photoreceptor using a novel photoconductive coating.

A fourth object of the present invention is to provide an electrophotographic photoreceptor suitable for electrophotographic copying machines.

A fifth object of the present invention is to provide an electrophotographic photoreceptor suitable for a laser beam scanning type electrophotographic glitter.

A sixth object of the present invention is to provide an electrophotographic photoreceptor having high sensitivity to light in a long wavelength range.

Means for Solving the Problems The present invention provides a photoconductive film having an azulenium salt compound represented by the following general formula, and an electrophotographic photoreceptor including a photosensitive layer having the compound, in the general formula: R1-R7 represent a hydrogen atom, a halogen atom (chlorine atom, bromine atom, iodine atom) or a monovalent organic residue. Monovalent organic residues can be selected from a wide variety of groups, but especially alkyl groups (methyl, ethyl, n-
furoyl, isopropyl, n-butyl, t-butyl, n
-amyl, n-hexyl, n-octyl, 2-ethylhexyl, t-octyl, etc.), alkoxy groups (methoxy, ethoxy, propoxy, butoxy, etc.), substituted or unsubstituted aryl groups (phenyl, tolyl, xylyl,
ethylphenyl, methoxyphenyl, ethoxyphenyl, chlorophenyl, nitrophenyl, dimethylaminophenyl, α-naphthyl, β-naphthyl, etc.), substituted or unsubstituted heterocyclic groups (pyridyl, quinolyl, carbazolyl, furyl, chenyl, pyrazolyl, etc.) , substituted or unsubstituted aralkyl groups (benzyl, 2-phenylethyl, 2-phenyl-1-methylethyl, bromobenzyl, 2-bromophenylethyl, methylbenzyl, methoxybenzyl, nitrobenzyl), acyl groups (acetyl, globionyl) , butyryl, valeryl, benzoyl, trioyl, naphthoyl, phthaloyl, furoyl, etc.),
Substituted or unsubstituted amine 7 groups (amino, dimethylamino, diethylamino, diethylamino, acetylamino,
benzoylamide 7, etc.), substituted or unsubstituted styryl groups (styryl, dimethylaminostyryl, noethylaminostyryl, dimethylaminostyryl, methoxystyryl, ethoxystyryl, methylstyryl, etc.), nitro group, hydroxy group, mercapto group, thioether group , carboxyl group, carmenic acid ester, carboxylic acid amide, cyano group, substituted or unsubstituted arylazo group (phenylazo, α-naphthylazo, β-7tylazo, dimethylaminophenylazo, chlorophenylazo, nitrophenylazo, methoxyphenylazo, tolylazo, etc.). Also, R1 and R2, R2 and R3
, R3 and R4, R4 and R5, R5 and R6 and R6 and R
, at least one combination may form a substituted or unsubstituted condensed ring. As a fused ring, it is 5-membered,
It is a condensed ring of 6-membered and 7-membered rings, and includes aromatic rings, heterocycles, and aliphatic chains.

R8 and R9 are alkyl groups (methyl, ethyl, n-
furoyl, isopropyl, n-butyl, t-butyl, n
-amyl, n-hexyl, n-octyl, 2-ethylhexyl, t-octyl, etc.) substituted or unsubstituted aryl groups (phenyl, tolyl, xylyl, ethylphenyl, chlorophenyl, nitrophenyl, methoxyphenyl, ethoxyphenyl, α- naphthyl, β-naphthyl, etc.) or a substituted or unsubstituted aralkyl group (-'!ndyl, 2-phenylethyl, 2-phenyl-1-methylethyl, methylbenzyl, methoxypennol, nitrobenzyl, etc.). Further, R8 and R9 can form a 5- to 6-membered ring (morpholino, pyrrolidino, biperidinyl biberano, phenothiatsuno, phenoxazono, carbazolyl, indolyl, pyrrolyl, pyrazolyl, etc.) together with the crab atom.

Arl and Ar2 represent substituted or unsubstituted arylene, M (phenylene, 1.4-naphthylene, 1.5-naphthylene, 9.10-antrylene, etc.). Examples of substituents include alkyl groups (methyl, ethyl, n-globil, isonorogyl, n-butyl, 1-butyl, n-hexyl, 2-ethylhexylnato), alkoxy groups (methoxy, ethoxy, tetrapoxy, butoxy, etc.) ), helogne atoms (chlorine atom, bromine atom, iodine atom), etc.

2θ represents an anionic residue, and a specific example of zo is
Noya-chlorate, fluoroborate, sulfoacetate, iodide, lypride, bromide, P-)
Represents anionic residues such as luenesulfonate, alkylsulfonate, alkylsulfonate, benzenedisulfonate, herosulfonate, vicrate, tetracyanoethylene anion, tetracyanoquinodimethane anion, etc.

Specific examples of the azulenium salt compounds used in the present invention are listed below.

Compound shop Compound examples H3 Oh.

. H3/ F40 Oh.

0H30,! . O. 1o40 (1B) The compound represented by general formula (1) is Journato
f the chemical Society P, 1
110-P, 1117 (1958), Journalat
of the chemicalSocietyP, 4
94-P, 501 (1960) and Journat
of the chemlcatSocietyP,
3579-P, 3593 (1961), by mixing an azulene compound and a corresponding aldehyde compound in a suitable solvent in the presence of a strong acid.

Reaction solvents used include alcohols such as ethanol, butanol, and benzyl alcohol, nitriles such as acetonitrile and norobionitrile, organic carmenic acids such as acetic acid, acid anhydrides such as acetic anhydride, and alicyclics such as dioxane and tetrahydrofuran. Formula ethers, etc. are used. Furthermore, aromatic hydrocarbons such as benzene can be mixed with butanol, benzyl alcohol, and the like. The temperature during the reaction can be selected from the range of room temperature to boiling point.

The coatings containing the azulenium salt compounds described above are photoconductive coatings and can therefore be used in photosensitive layers of subsequent electrophotographic photoreceptors.

That is, in a specific example of the present invention, Li is placed on a conductive support.
The electrophotographic photoreceptor 54 can be manufactured by forming a film using the azulenium salt compound described in J above by vacuum evaporation, or by dissolving or dispersing it in a suitable binder to form a film.

In a preferred embodiment of the present invention, the photoconductive coating described in niJ is applied as a charge generating layer in an electrophotographic photoreceptor in which the photosensitive layer is functionally separated into a charge generation layer and a charge transport layer. I can do it.

The charge generation layer contains as much of the above-mentioned photoconductive compound as possible in order to obtain sufficient absorbance, and is thin (1f!) in order to increase the range of the generated charge carriers.
, i-layer, e.g. 5μ or more, preferably 0801-1μ
It is preferable to form a thin film layer having a thickness of .

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.

The charge-generating Nh can be formed by dissolving or dispersing the above-mentioned compound in a suitable binder and coating it on the entire substrate, or can be obtained by forming a vapor deposited film using a vacuum vapor deposition system H. The padder 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-vinicarbazole, polyvinylanthracene, and polyvinylpyrene. can. Preferably, polyvinyl butyral, polyarylate (condensation polymer of bisphenol A and heptalic acid, etc.), polycarbonate, polyester, phenoxy resin, polyvinyl acetate, acrylic resin, polyacrylamide, polyamide, polyvinylbilinone, cellulose resin, Examples include insulating resins such as urethane resin, epoxy WU=, casein, polyvinyl alcohol, and polyvinylpyrrolidone. The resin contained in the charge generation layer is suitably 80% by weight or less, preferably 40% by weight or less.

The solvent that dissolves these resins varies depending on the type of resin, and is preferably selected from those that do not dissolve the underlying charge transport layer or subbing layer. Specifically, organic solvents include alcohols such as methanol, ethanol, and isopropanol, ketones such as a7tone, 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, aliphatics such as chloroform, methylene chloride, dichloroethylene, carbon tetramide, and trichloroethylene. Halogenated hydrocarbons or benzene, toluene, xylene, ligroin, monochlorobenzene,
Aromatics such as dichlorobenzene can be used.

M-technology includes dip coating method, spray coating method, spinner coating method, bead coating method,
This can be carried out using a coating method such as a Mayer bar 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 can be carried out at a temperature of 30° C. to 200° C. for a period of time ranging from 5 minutes to 2 hours, either stationary or under ventilation.

The charge transport layer is electrically connected to the charge generation layer described above, 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.

The substance that transports charge carriers in the charge transport layer (hereinafter simply referred to as charge transport substance) is preferably substantially insensitive to the wavelength range of electromagnetic waves to which the charge generation layer is sensitive. The "electromagnetic waves" referred to here, rIIil, X
The definition of "r-rays" in a broad sense includes all rays, ultraviolet rays, visible rays, near infrared rays, infrared rays, far infrared rays, etc. When the photosensitive wavelength range of the charge transport layer coincides with or overlaps that of the charge generation layer, charge carriers generated in both layers capture each other, resulting in a decrease in sensitivity.

[Cargo transport substances include electron transport substances and hole transport substances, and electron transport substances include chloranil, bromoanil, tetracyanoethylene, tetracyanoquinodimethane, 2,4.7-)dinitro-9 -fluorenone,
2,4,5.7-tetranitro-9-fluorenone, 2
, 4.7-) dinitro-9-nocyanomethylenefluorenone, 2゜4.5.7-titranitroxanthone, 2゜4.8-) linito-p-thioxanthone and other electron-withdrawing substances and these electron-withdrawing mobilization agents. There are polymerized ones.

Examples of hole-transporting substances include pyrene, N-ethylcarbazole, N-isopropylcarbazole, N-methyl-N
-Phenylhydrazo/-3-methylidene-9-ethylcarba/-l, N,N-diphenylhydrazino-3-methylidene-9-ethylcarbazole, N,N-diphenylhydrazino-3-methylidene-10-ethyl Fetch Ryojin, N, N-diphenylhydrazone-3-methylidene-10-ethylphenoxazine, P-diethylaminobenzaldehyde-N, N-diphenylhydrazone, P
-diethylaminobenzaldehyde-N-α-naphthyl-N-phenylhydrazone, p-pyrrolidi/benzaldehyde-N,N-diphenylhydrazone, 1,3.3-
) Dimethylindolenine-ω-aldehyde-N,N-diphenylhydrazone, P-diethylbenzaldehyde-
Hydrazones such as 3-methylbenzthiazolinone-2-hydrazone, 2,5-bis(p-diethylaminophenyl)-1,3,4-oxadiazole, 1-phenyl-
3-(P-dimethylaminostiri/I/)-s-(p
-diethylaminophenyl)pyrazoline, 1-[quinolylf21) -3-(P-diethylaminostyryl)-5-(P-diethylaminophenyl)pyrazoline,
X-[pyrisol t2+) -3-(P-diethylaminostyryl)-5-(P-diethylaminophenyl)pyrazoline, 1-(6-medoxyviridyl(21)) -
3-(P-diethylaminostyryl)-5-(P-diethylaminophenyl)pyrazoline, 1-[pyridyl(3
1) -3-(P-diethylaminostyryl)-5-(
P-diethylaminophenyl)pyrazoline, 1-[levidyl(2+)-3-(P-diethylaminostyryl)-5-(P-noethylami/phenyl)pyrazoline,
1-(pyridyl(2+)-3-(P-diethylaminostyryl)-4-methyl-3-(P-diethylaminophenyl)pyrazoline, 1-[pyridyl(2+)-3
-(α-methyl-P-diethylaminostyryl)-5-
(P-diethylaminophenyl) hilazoline, 1-phenyl-5-(P-diethylaminostyryl)-4-methyl-3-(P-diethylaminophenyl) pyrazoline,
1-PhenyA/-5-(α-benzyl-P-diethylaminostyryl)-5-(P-diethylaminophenyl)
Pyrazolines such as pyrazoline and spiropyrazoline, 2
-(P-diethylaminostyryl)-6-dinithylaminopenzoxazole, 2-(P-diethylaminophenyl)-4-(p-tumethylami/phenyl)-5-(
Nooxazole compounds such as 2-10lophenyl)oxazole, 2-(P-)x-f-ruaminostyryl)-6
-thiazole thread compounds such as dinithylaminobenzothiazole, triarylmethane compounds such as bis(4-diethylamino-2-methylphenyl)-phenylmethane,
1,1-bis(4-N.

N-diethylamino-2-methylphenyl)hebutane,
Polyarylalkanes such as 1,1,2.2-tetrakis(4-N,N-dimethylamino-2-methylphenyl)ethane, triphenylamine, poly-N-vinylcarbasol, polyvinylpyrene, polyvinylanthracene, Examples include polyvinyl acridine, poly-9-vinylphenylanthracene, pyrene-formaldehyde resin, and ethylcarbazole formaldehyde resin.

In addition to these organic charge transport materials, inorganic materials such as selenium, selenium-tellurium amorphous silicon, and cadmium sulfide can also be used.

Further, these charge transport substances can be used singly or in combination of two or more.

When a substance does not have film-forming properties for charge transport, a film can be formed by selecting an appropriate binder. Examples of resins that can be used as binders include acrylic resins, polyarylates, polyesters, polycargonates,
Polystyrene, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene copolymer, polyvinyl butyral, polyvinyl formal, polysulfone,
Examples include insulating resins such as polyacrylamide, polyamide, and chlorinated rubber, and organic photoconductive polymers such as poly-N-vinylcarbazole, polyvinylanthra7ane, and polyvinylpyrene.

Since the charge transport layer has a limit in its ability to transport charge carriers, it cannot be made thicker than necessary. Generally, it is 5 to 30μ, but the preferred range is 8 to 20μ.
It is. When forming the charge transport layer by coating, an appropriate coating method as described above can be used.

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,
Niracle, indium, gold, platinum, etc. can be used, and in addition, plastics having a layer formed by vacuum evaporation of aluminum, aluminum alloy, indium oxide, tin oxide, indium oxide-tin oxide alloy, etc. For example, polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, acrylic resin,
(boriated ethylene, etc.), conductive particles (e.g., carbon black, silver particles, etc.) coated on a glass substrate with a suitable binder (substrates made of plastic or paper impregnated with conductive particles), Plastics containing conductive polymers, 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-
Acrylic version copolymer, polyamide (nylon 6, nylon 66, nylon 610, copolymerized nylon, alkoxymethylated nylon, etc.), polyurethane, gelatin,
It can be formed from aluminum oxide, etc.

The thickness of the subbing layer is 0.1 to 5μ, preferably 0.5 to 3μ.
μ is appropriate.

When using an I^ photobody in which a conductive layer, a charge generation layer, and a charge transport layer are laminated in this order, and the charge transport material is an electron transport material, the surface of the charge transport layer must be positively charged, and the charging When post-exposure is carried out, the 1u molecules generated in the charge generation layer are injected into the charge transport layer in the exposed area, and then reach the surface layer and neutralize the positive charge, causing a decrease in the surface potential and causing the oxidation of the parts of Mikuni. An electrostatic contrast occurs between them. A visible image can be obtained by developing the electrostatic latent image thus formed with a fully negatively charged toner. This can be directly fixed, or the toner image can be transferred onto paper, a plastic film, etc., and then developed and fixed.

Alternatively, a method may be used in which the electrostatic latent image on the photoreceptor is transferred onto an insulating layer of transfer paper, then developed and fixed. The phase order of the developer, the developing method, and the fixing method may be all known methods or methods, and are not limited to any particular method.

On the other hand, when it is made of a charge transport material or a hole transport material, the surface of the charge transport layer must be negatively charged, and when exposed to light after charging, holes generated in the charge generation layer are injected into the charge transport layer in the exposed area. , which then reaches the surface and neutralizes the negative charges, resulting in attenuation of the surface potential and an electrostatic contrast between the surface potential and the unexposed area.

In contrast to the case where a Vi electron transporting material is used during development, it is necessary to use a positively charged toner.

Further, in another specific example of the present invention, the above-mentioned hydrazones,
Organic photoconductive substances such as pyrazolines, oxazoles, thiazoles, triarylmethanes, polyaryl alkanes, triphenylamine, poly-N-vinylcarbazoles, and inorganic photoconductive substances such as zinc oxide, cadmium sulfide, and selenium. A photosensitive film containing all of the above-mentioned compounds as sensitizers can be obtained. This photosensitive coating is formed by coating these photoconductive substances and the above-mentioned compound r$/J'ft binder.

In any of the photoreceptors, the sensitivity of the photoreceptor can be fully maximized by containing at least one type of azulenium salt mentioned above, and if necessary, using a combination of other photoconductive pigments or dyes with different light absorption. It is also possible to prepare it as a panchromatic photoreceptor.

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

Examples 1 to 8 Ammonia aqueous solution of casein (casein 1
1.2r, 28% ammonia water 12, water 222v) It was coated with Mayer glue so that the film thickness after drying was 1.0μ, and dried.

Next, butyral resin (butyralization degree 63 mol%) 2
A coating solution of 8& was prepared by adding each of the 8 types of azulenium salt compounds 52 listed in the table below to a solution of 2 dissolved in 95 ml of isozolobyl alfur.

After dispersing each coating solution using an attritor, each coating solution is applied onto the casein undercoat layer using a Meyer glue so that the film thickness after drying is 0.1μ, and dried to form a charge generation layer. I let it happen.

Next, a hydrazone compound 51 of the structural formula and a polymethyl methacrylate resin (number average molecular weight 100.000) 52 total benzene 7 (
lx/, and applied onto the charge generation layer using a Mayer bar so that the film thickness after drying was 12 μm, and dried to form a charge transport layer.

The 8 electrophotographs created in this way/6 light bodies were corona-charged statically at 5 KV using a Zenkawa Roden Co., Ltd. Seiden Copying Paper Tester Model 5P-428, and held in a dark place for 10 seconds. After that, it was exposed to light at an illuminance of 5 tux and the charging characteristics were examined.

As for the charging characteristics, the initial charging potential (■.) and the exposed area (El/2) required to attenuate the potential to 172 when darkened for 10 seconds were measured. The results are shown in Table 1. Further, the charge retention rate when darkened for 10 seconds was expressed as VK (%).

1st Table 1 (11530812, 3 2 (2) 54580 4.5 3 (3) 51081 2.84 (71
525837,8 5Qo 57084 5.5 6 H5258710,4 7 (Is 58585 6.4 80υ 54084 12.5 Example 9 ?Reester resin (manufactured by Toyobo ■, Byron 200)!
M' and 1-[virigilou (2)]-5-(4-N, N-
After dissolving (noethylaminostyryl)-5-(4-N,N-noethylaminophenyl)pyrazoline 52 in methyl ethyl ketone 801, the aforementioned azulenium salt compound A
(After adding and dispersing 211, Of', it was applied and dried on a polyester film deposited with aluminum, and the dry film thickness was 13
A photoreceptor having all photosensitive layers of μ was prepared.

The characteristics of this photoreceptor were determined by the same method as in Example 1, including the initial charging potential (■.), the charge retention rate (VK, ) when dark decayed for 10 seconds, and the charging potential when dark decayed for 10 seconds. /2, and the results were as follows.

Vo: -430V VK: 81% E1/2 "38・5t"z°see Example 1
0 to 14 Photosensitized in exactly the same manner as in Example 9, except that the azulenium salt compound A (21) used when preparing the photoreceptor in Example 9 was replaced with the azulenium salt compound listed in the table below. The charging characteristics of each photoreceptor were measured.

These results are shown in Table 2.

2nd Table 10 (115108125,9 11(5) 48584 40.5 12 (615208756,8 13(8) 51080 35.5 14 (16) 50583 41.6 Example 15 del)-N-vinylcarbazole 11 and the above 5μ of azulenium salt compound A(2) was added to 10F of 1,2-dichloroethane and thoroughly stirred.The thus prepared coating solution was coated on polyethylene terephthalate film deposited with aluminum to a dry film thickness of 15μ. It was applied using a doctor blade.

The charging characteristics of this photoreceptor were measured in the same manner as in Example 1. However, the charging polarity was set to ■. The results are shown below.

Vo: +520V VK: so% 81/2" 37.5 tux°see Example 16 In place of the azulenium chloride hardware (2) used when preparing the electrophotographic photoreceptor of Example 15, the azulenium chloride described above was used. A photoconductor was prepared in exactly the same manner as in Example 15, except that the entire circumference of the hardware store (7) was used, and then the charging characteristics of this photoconductor were measured.The results are shown below.However, the charging polarity was And so.

■. : +470V VK : 78% Example 17 Fine particle zinc oxide (Sakai Chemical ■5azex 2000) 1
02, acrylic resin (Dyanal LROO9 manufactured by Mitsubishi Rayon) 4i) Luene 102 and the above-mentioned azulenium salt compound A (1110) were thoroughly mixed in a ball mill, and the resulting coating liquid was coated with aluminum to form a polyethylene terephthalate film. A doctor grade coating was applied onto the film to give a dry film thickness of 21 μm and dried to prepare an electrophotographic photoreceptor.

When the spectral sensitivity of this electrophotographic photoreceptor was measured using spectrophotography using electrophotography, it was found that the photoreceptor of this example showed sensitivity on the long wavelength side compared to the aforementioned zinc oxide coating that did not contain an azulenium salt compound. It turned out that it has.

Example 18 An ammonia aqueous solution of casein was coated on an aluminum plate with a thickness of 100 μm and dried to form a subbing layer with a thickness of 1.1 μm.

Next, 2,4.7-) dinitro-9-fluorenone 5
2 and poly-N-vinylcarbazole (number average molecular weight 30
0,000) 5 f to tetrahydro 7 run 701Ll
to form a charge transfer complex. This charge transfer complex compound and the aforementioned azulenium salt compound A (4114) were added to a solution in which polyester resin (Vylon: manufactured by Toyobo Co., Ltd.) 51 was dissolved in 70+t/t of tetrahydrofuran and dispersed. This dispersion was dried on the undercoat layer. The photoreceptor thus prepared was coated to a film thickness of 12 μm and dried.The charging characteristics of the photoreceptor thus prepared were measured in the same manner as in Example 1.The results were as follows.

However, the charging polarity was set as ■.

Vo: +460V VK: 82% E1/2: 12.5 tux-see Example 1
9. A polyvinyl alcohol film with a thickness of 11 μm was applied on the aluminum surface of the aluminum vapor-deposited polyethylene terephthalate film.
tV formation L ft.

Next, the coating solution containing the azulenium salt compound of Example 3 was applied onto the previously formed polyvinyl alcohol layer using Mayer glue so that the film thickness after drying was 0.1μ, and dried. A charge generation layer was formed.

Next, a solution prepared by dissolving pyrazoline compound 52 and polyarylate (condensation polymer of bisphenol A and terephthalic acid-iso7thalic acid) 5 in tetrahydrofuran 70n1e with the structural formula was placed on the charge generation layer so that the film thickness after drying was 10 μm. A charge transport layer was formed by coating and drying.

The charging properties of the photoreceptor thus prepared were measured in the same manner as in all Examples. The results are shown below.

Vo: -320V VK: 84% E1/2. : 3.21ux°aec Example 2
0 Aqueous ammonia solution of casein (casein 1122.28% ammonia water 12, water z
22y)k It was coated by a dip coating method and dried to form a subbing layer with a coating weight of 1 and Of/m'.

Next, 1 part by weight of the above-mentioned azulenium chloride hardware store (2), 1 part by weight of butyral resin (S-LEC BM-2, manufactured by Tanemizu Kagaku ■) and 30 parts by weight of isonorobyl alcohol were dispersed for 4 hours using a ball mill disperser. did. This dispersion was applied onto the previously formed subbing layer by a dip coating method and dried to form a charge generating layer. The film thickness at this time was 0.3μ.

Next, 1 part by weight of P-diethylaminobenzaldehyde-N-phenyl-N-α-su7tylhydrazone, 1 part by weight of polysulfone (P1700: manufactured by Union Carbide), and 6 parts by weight of monochlorobenzene were mixed, and the mixture was stirred with a stirrer. Dissolved. This liquid was applied onto the charge generation layer by dip coating and dried to form the entire charge transport layer. The film thickness at this time was 12μ.

Corona discharge of -5 kV was applied to the photoreceptor thus prepared. The surface potential at this time was measured (initial potential ■).

Furthermore, the surface potential of this photoreceptor was measured after it was left in a dark place for 5 seconds (dark decay Vk). Sensitivity is determined by the amount of exposure (E1/2) required to attenuate the potential Vk to 1/2 after dark decay.
Evaluation was made by measuring microjoules/7). At this time, gallium and aluminum arsenide semiconductor lasers (all with an oscillation wavelength of 780 nm) were used as the light source.The results were as follows.

Vo' -340V vk: 86% E total = 3.2 microjoules/ct
Ig Examples 21-24 Azulenium salt compound A used in Example 20 (2)
A photoreceptor was prepared in exactly the same manner as in Example 20, except that the compounds shown in Table 3 were used in place of K, and the characteristics of this photoreceptor were measured.

All of these results are shown in Table 3.

3rd Table 21 fl) 55081 2.122 (6
) 53074 6.823 (91545B3
4. ．． 5 24 αη 56082 3.4 Effects of the Invention As is clear from the foregoing, according to the present invention, a highly sensitive electrophotographic photoreceptor can be obtained, and is particularly effective for laser beams having an oscillation wavelength on the long wavelength side. It is possible to obtain improved electrophotographic characteristics.

Claims (2)

[Claims] (1) A photoconductive film containing an azulenium salt compound represented by the following general formula. General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ However, in the formula, R_1, R_2, R_3, R_4, R_5
, R_6, and R_7 represent a hydrogen atom, a halogen atom, or a monovalent organic residue, and R_1 and R_2, R_2 and R_3, R_3 and R_4, R_4 and R_5, R_5 and R
At least one combination of _6 and the combination of R_6 and R_7 may form a substituted or unsubstituted fused ring. R_8 and R_9 represent a substituted or unsubstituted alkyl group, aryl group or aralkyl group. or,
R_8 and R_9 may form a ring together with the nitrogen atom. Ar_1 and Ar_2 represent substituted or unsubstituted arylene groups. Z^■ represents an anionic residue. (2) An electrophotographic photoreceptor characterized in that a photosensitive layer having an azulenium salt compound represented by the following general formula is provided on a conductive support. General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ However, in the formula, R_1, R_2, R_3, R_4, R_5
, R_6 and R_7 are hydrogen atoms, halogen atoms, or 1
R_1 and R_2, R_2 and R_3, R_3 and R_4, R_4 and R_5, R_5 and R
At least one combination of _6 and the combination of R_6 and R_7 may form a substituted or unsubstituted fused ring. R_8 and R_9 represent a substituted or unsubstituted alkyl group, aryl group or aralkyl group. or,
R_8 and R_9 may form a ring together with the nitrogen atom. Ar_1 and Ar_2 represent substituted or unsubstituted arylene groups. Z^■ represents an anionic residue.