JPS61181867A - Phthalocyanine composition and electrophotographic material obtained by using same - Google Patents

Abstract

PURPOSE:To obtain a phthalocyanine compsn. which does not cause any problems on hygiene and is useful for electrophotographic material, by blending phthalocyanine with its derivative substituted with an electron-attractive group and an electron-donating group. CONSTITUTION:A phthaloxyanine compsn. contains a phthalocyanine and its derivative in which the benzene nucleus of the phthalocyanine molecule substituted with at least one electronattractive group selected from among halogen, nitro, sulfone, carboxyl and trifluoromethyl groups and at the least one electron-donating group selected from among alkoxy, aryloxy, alkylthio and aralkylthio groups. Examples of the phthalocyanines are metal-free phthalocyanine, metal phthalocyanines and mixtures thereof. The central nucleus of the phthaloxyanine in not limited to metallic atoms, but may be tri- or polyvalent metal halide.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to a phthalocyanine composition, and particularly to such a composition useful for optical semiconductor materials 2, such as electrophotographic photoreceptors. Furthermore, the present invention relates to an electrophotographic photoreceptor for use in general copying machines or laser printers, which has excellent photosensitivity from the visible light region to long wavelength light such as semiconductor laser light of 780 nm or more.

(Prior Art) It is known that phthalocyanine compositions can be used as optical semiconductor materials and the like. Applications of optical semiconductor materials include electrophotographic photoreceptors and solar cells.

Examples include electrophotographic plate-making materials and sensors.

Electrophotography has already been developed by Carlson with US Patent No. 2゜29.
As disclosed in No. 7.691, this photographic method is a clever combination of photoconductivity and electrostatic phenomena, and the surface of a photoconductive photoreceptor is uniformly illuminated by corona discharge etc. in a dark place. It is a type of image forming method that uses photoconductivity to convert a light image into an electrostatic latent image after being charged in a similar manner, and then a colored charged powder (toner) is attached to this to turn it into a visible image. .

The basic electrical and photoelectric properties required of a photoreceptor in such electrophotography are that it can be charged to an appropriate potential in a dark place, and that the charge can be quickly dissipated by light irradiation. Examples include.

Conventionally, inorganic photoconductive substances such as amorphous selenium, cadmium sulfide, and zinc oxide have been widely used as photoconductive elements for such electrophotographic photoreceptors.

Although these inorganic materials satisfy the above conditions, they also have some drawbacks. For example, cadmium sulfide and zinc oxide are used as photoreceptors by being dispersed in resin as a binder, but they have mechanical drawbacks such as smoothness, flexibility, hardness, tensile strength, and abrasion resistance, so they are used as is. cannot withstand repeated use.

Furthermore, when using cadmium sulfide, consideration must also be given to hygiene issues.

In addition, amorphous selenium must be manufactured by vapor deposition, which not only increases manufacturing costs but also has no flexibility and is difficult to process into a belt shape.
It has drawbacks such as the toxicity of selenium and its sensitivity to heat and mechanical shock, so care must be taken when handling it.

In recent years, in order to eliminate the drawbacks of these inorganic photoreceptors,
Research on organic photoreceptors is progressing, and organic photoreceptors.

Easy to form a film, easy to manufacture, lightweight.

Various organic photoreceptors have been proposed that take advantage of many advantages such as flexibility and polymorphism in spectral sensitivity, and some of them are in practical use.

In general, organic photoreceptors can be broadly classified based on the structure of the photoreceptor.

1) Usually called a single-layer photoreceptor, like the conventional inorganic photoreceptor using zinc oxide and cadmium sulfide,
An organic photoconductor element dispersed in a binder resin. Furthermore, as described in U.S. Pat. No. 3,764,315, a substance that generates electric charge by light (referred to as a charge-generating substance) is used to transport the generated electric charge. Photoreceptors are known that have a photosensitive layer whose characteristics are improved by dispersing a substance (referred to as a charge transporting substance) in a layer containing a charge transporting substance.

2) It is called a functionally separated laminated photoreceptor.

A highly sensitive photoreceptor is obtained by performing charge generation and charge transport in separate layers. As a method of this type, as in US Pat. No. 3,791,826, it has been proposed to provide a highly sensitive photoreceptor by providing a charge transport layer on a charge generation layer.

By the way, many of the substances known as charge-generating substances are azo dyes such as chlorodiane blue, or colored dyes such as phthalocyanine pigments, and since these alone have low charge-generating ability, they cannot be charged to reach practical sensitivity. In order to draw out the generated power, it must be contained in a large amount in the photoreceptor. By the way, in the case of a single-layer type photoreceptor, if a large amount of such colored dye is contained, the mechanical strength of the photoreceptor will be weakened, and from another point of view, it will cause a decrease in charging property,
Due to the decrease in charge retention ability and the strong molecular absorbance of the charge-generating substance, effective light does not penetrate sufficiently into the photosensitive layer, making it impossible to generate sufficient charge inside the photosensitive layer. On the other hand, it also causes a decrease in sensitivity.

In view of this, a functionally separated photoreceptor has been proposed which improves the drawbacks of the single-layer photoreceptor described above. In the case of bifunctionally separated photoreceptors, there are few compounds that are excellent as charge-generating substances, so at present, even more excellent photoreceptors are obtained by improving the charge transporting material. However, such laminated photoreceptors generally contain a large amount of charge-generating substance in the charge-generating layer, and furthermore, the thickness needs to be uniform, less than 5μ, and practically less than 1μ. Therefore, there are technical difficulties. In addition, due to the large amount of charge generating substance in the charge generating layer, adhesion to the supporting substrate is insufficient and mechanical strength also becomes a problem. Furthermore.

Charges generated at the interface between the charge generation layer and the charge transport layer are trapped, which often causes changes in sensitivity during continuous use.
Improvements such as providing a subbing layer are also being considered.

By the way, in recent years, with the progress of semiconductor lasers, these semiconductor laser lights have been utilized in computers and optical communications. An output method using electrophotography has been proposed, and a photoreceptor that is sensitive to semiconductor laser light is required for this purpose. However, the wavelength of semiconductor laser light currently in practical use is 78% even for laser light from gallium and arsenic semiconductors, which emit the shortest wavelength laser.
Currently, phthalocyanine is the most well-known organic photoreceptor element that is sensitive to such long wavelengths, but even this phthalocyanine has insufficient sensitivity for practical use. Therefore, methods of sensitization using compounds such as trinitrofluorenone and tetracyanoquinodimethane have been proposed, but these compounds are highly toxic and have problems in their practical use.

(Problems to be Solved by the Invention) The present invention improves the above-mentioned drawbacks of phthalocyanine and provides a phthalocyanine composition particularly useful for electrophotographic photoreceptors.

"Structure of the Invention" (Means for Solving the Problems) The present invention provides phthalocyanine and a benzene nucleus of the phthalocyanine molecule having a nitro group, a halogen atom, a sulfone group,
at least one electron-withdrawing group selected from a carboxyl group and a trifluoromethyl group and an alkoxy group,
A phthalocyanine composition containing a phthalocyanine derivative substituted with at least one electron-donating group selected from aryloxy, alkylthio, and aralkylthio groups.

Furthermore, the phthalocyanine and the benzene nucleus of the phthalocyanine molecule include at least one electron-withdrawing group selected from a nitro group, a halogen atom, a sulfone group, a carboxyl group, and a trifluoromethyl group, and an alkoxy group, a ryoxy group, and an alkylthio group. The phthalocyanine according to the present invention, which is an electrophotographic photoreceptor having a photosensitive layer containing a phthalocyanine derivative substituted with at least one electron-donating group selected from It is a mixture of Metals of metal phthalocyanine include copper, 嘗艮, beryllium, and magnesium.

Calcium, zinc, cadmium, beryllium, mercury, gallium, indium, lanthanum, neodymium.

These include titanium, tin, lead, vanadium, antimony, chromium, molybdenum, uranium, manganese, iron, cobalt palladium, aluminum and platinum.

In addition, the central nucleus of phthalocyanine is not a metal atom (
, a metal halide having a valence of 3 or more. Metal-free phthalocyanines and metal phthalocyanines such as copper, cobalt, lead, and zinc are preferred. Furthermore, it may be a low halogenated phthalocyanine. Although phthalocyanine is a well-known compound as a pigment, in the present invention, phthalocyanine obtained by any manufacturing method may be used. Phthalocyanine may also be used. It is also known that phthalocyanine can be obtained in various crystal forms depending on the synthesis method, purification method, and pigmentation conditions. For example, copper phthalocyanine.

α type, β type, T type, δ type, ε type, χ type, and also. As for metal-free phthalocyanine, α-type, β-type, γ-type, δ-type, ε-type, χ-type, τ-type, etc. are known, but the present invention is not limited to these crystal forms.

The phthalocyanine derivatives according to the present invention include:

During phthalocyanine synthesis, the benzene nucleus of the phthalocyanine raw materials, such as phthalonitrile, phthalic acid, phthalic anhydride, and phthalimide, becomes a nitro group,
Substituted with at least one electron-withdrawing group selected from halogen atoms, sulfone groups, carboxyl groups, and trifluoromethyl groups and at least one electron-donating group selected from alkoxy groups, aryloxy groups, alkylthio groups, and aralkylthio groups. Although it can be easily obtained by using raw materials such as
The method for producing the phthalocyanine derivative is not particularly limited.

Examples of electron donating groups include methoxy group, ethoxy group,
Propoxy group, butoxy group, amyloxy group.

Stearyloxy group, ary-(R
is an alkyl group, a halogen atom, a nitro group, etc.) A methylthio group, an ethylthio group, a propylthio group, a butylthio group, an amylthio group, a stearylthio group, etc.

Further, the number of substituents in the phthalocyanine derivative molecule is on average 2-8, more preferably 2-4. The number of substituents varies depending on the manufacturing method, but different numbers of substituents are often mixed. In addition, as the phthalocyanine derivative, for example, a phthalocyanine derivative having a nitro group and an alkoxy group, and a phthalocyanine derivative having a cyano group and an alkylthio group may be used in combination. Furthermore, some phthalocyanines other than the phthalocyanine derivatives of the present invention can also be used in combination.

In addition, the parent skeleton of phthalocyanine in phthalocyanine derivatives is metal-free phthalocyanine or copper.

Nickel, cobalt iron, sodium, lithium.

Metal phthalocyanines such as calcium, magnesium, and aluminum. The composition ratio of phthalocyanine and phthalocyanine derivative is 0.01 to 20 parts by weight per 100 parts by weight of phthalocyanine. Preferably, the amount of the phthalocyanine derivative is 0.1 to 5 parts by weight. If it is less than 0.01 parts by weight, sufficient sensitivity cannot be obtained, and if it exceeds 20 parts by weight, the dark decay rate increases and it cannot be put to practical use.

In addition, in the present invention, as a method for incorporating these phthalocyanine derivatives into the phthalocyanine photosensitive layer, both may be mechanically kneaded when forming the photosensitive layer.
Preferably, the phthalocyanine and the phthalocyanine derivative are in contact with each other as much as possible, and for this purpose, the phthalocyanine and the phthalocyanine derivative are treated in advance under mechanical strain such as in a ball mill or kneader, or Alternatively, it is preferable to use an acid pasting or acid slurry method in which the phthalocyanine and the phthalocyanine derivative are dissolved in an inorganic acid capable of forming a salt with the phthalocyanine, and then the phthalocyanine is reprecipitated with water or an alkaline compound. As inorganic acids that can form salts with these phthalocyanines.

Sulfuric acid, orthophosphoric acid, birophosphoric acid, chlorosulfonic acid,
Hydrochloric acid, hydroiodic acid, hydrofluoric acid, etc. are used.

9 The structure of the photoreceptor according to the present invention is the single-layer type 1 described above.
Either function-separated structure may be used, and may be appropriately selected depending on the intended use of the photoreceptor. In this case, when a charge transport layer is used in combination, charge transport materials (b) used include hydrazone compounds, pyrazoline compounds, oxadiazole compounds, triphenylamine compounds, and other known charge transport materials. substance can be used. Hydrazone compounds can usually be obtained by condensing a hydrazine derivative with an aldehyde component or a ketone component. Specific examples of hydrazone compounds include the following compounds. p-N
-dimethylaminobenzaldehyde-N-phenylhydrazone, p-N-diethylaminobenzaldehyde-N
-phenylhydrazone, p-N-diethylaminobenzaldehyde-N,N-diphenylhydrazone, 3-(N
-diphenylhydrazone)-methyl-9-ethylcarbazole, 3-(N-methyl-N-phenylhydrazone)
-Methyl-9-ethylcarbazole, P-N-diethylaminobenzaldehyde-N, N-ethyl-phenylhydrazone, diethylaminobenzaldehyde-methyl-phenylhydrazone, diethylaminobenzothiazole-carbaldehyde diphenylhydrazone, and the like.

Further, oxadiazole compounds are usually obtained by ring-closing a compound having a carboxyl group with a hydrazone compound or a hydrazide compound using polyphosphoric acid or the like. Among many of these oxadiazole compounds, 2.
5-bis-(4dimethylaminophenyl 1)-1,3,
4-oxadiazole, 2,5-bis-(4-di-n-
propyl)-amino-phenyl 1-1.3.4-oxadiazole.

2.5-bis-(4-diethylaminophenyl-1)-
1,3,4-oxadiazole, 2,5-bis-(4-
Acetylamino-2-chlorophenyl-1)-1,3,
4-oxadiazole, 2.5-bis(4-n-propylaminophenyl-1)-1゜3.4-oxadiazole, 2.5-bis-(4-n-propylamino-2-chlor phenyl-1)-1,3,4-oxadiazole,
2,5-bis-(4-cyclohexylaminophenyl-
1) -1,3,4-oxadiazole, 2,5-bis-
(4-diethylaminostyryl)-1,3,4-oxadiazole and the like are specific examples of pyrazoline compounds such as 1-phenyl-3-(p-diethylaminostyryl)-5-(p-
diethylaminophenyl)-2Δ-pyrazoline, l, 5
-diphenyl-3-methyl-pitizoline, 1,3.5-
1-Riphenylpyrazoline, 1-(β)-naphthyl-3
-diphenyl-pyrazoline.

1.5-diphenyl-3-p-oxyphenyl-pyrazoline, 1,3-diphenyl-5-p-methoxyphenyl-pyrazoline, ■-p-ethoxyphenyl=3.5-diphenyl-pyrazoline, l-m-) Sol-3,5-diphenyl-pyrazoline, 1-p-tolyl-3,5-diphenyl-pyrazoline, 1-phenyl-3-p-methoxy-
styryl-5-p-methoxy-phenyl-pyrazoline,
l-phenyl-3-p-dimethylaminostyryl-5-
p-dimethylaminophenyl-pyrazoline, 1-p-nitrophenyl-3-p-styryl-5-phenyl-pyrazoline, 1.3-diphenyl-5-(p-dimethylamino)-phenyl-pyrazoline, 1.5- diphenyl-3
-styryl-pyrazoline. Further, specific examples of the triphenylamine composition include triphenylamine, tri(p-methylphenyl)-amine, and the like.

Since the phthalocyanine composition and the charge transport substance in the present invention usually do not have film-forming ability by themselves, a binder resin is used to form the photosensitive layer. However, if the charge transport material has a film-forming state or if a protective layer is to be formed on the photosensitive layer, the binder may not be used. The binder preferably used in the present invention is
Film-forming polymers with generally high electrical insulation properties,
Or it is a copolymer. Among such polymers and copolymers, binders preferably used in the present invention include phenol resins, amino resins, polyester resins,
Vinyl acetate resin, polycarbonate resin, polypeptide resin, cellulose resin, polyvinylpyrrolidone.

Polyethylene oxide, polyvinyl chloride resin, starch, polyvinyl alcohol, acrylic copolymer resin,
Examples include methacrylic copolymer resin, silicone resin, methacrylonitrile copolymer resin, polyvinyl butyral, polyvinylidene chloride resin, polyurethane resin, and polyvinyl carbazole.

These polymer binders may be used alone or in combination of two or more, but the binders that can be used in the present invention are not limited to these. Incidentally, the binder may be any thermoplastic one-reaction curing type.

In order to use the composition according to the present invention as an electrophotographic photoreceptor, the composition is used together with a binder resin, a solvent, and the like.

A photosensitive layer is formed by uniformly dispersing the mixture using a cross-dispersion machine such as a ball mill or attritor, and coating it on a conductive support. As a coating method, if necessary, a solvent is added to the photoconductive composition to adjust the viscosity, and an air doctor coater, blade coater, rod coater, reverse roll coater, etc.
Film formation is performed using a spray coater, hot coater, spray coater, etc. After coating, drying is carried out using a suitable drying device until the photoconductive layer is sufficiently charged. In addition, commonly used additives can also be used in the photosensitive layer, if necessary.

In addition, the ratio of the phthalocyanine composition to the binder in the present invention varies depending on the configuration of the photoreceptor selected, such as a single-layer dispersion type photoreceptor or a function-separated type photoreceptor, but the chargeability as a photoreceptor is maintained. 100 parts by weight of the binder.
~100 parts by weight is preferred. Further, the charge transport material is preferably 10 to 300 parts by weight per 100 parts by weight of the binder. However, it is not limited to this range only. Also.

The thickness of this photosensitive layer is determined by the required photosensitivity and durability and the mixing ratio of the phthalocyanine composition and the charge transport material to the binder, but it is preferably 50μ or less, especially 1
μ to 30 μ is preferable. If it exceeds this range, the film loses its flexibility, which may cause cracks, etc., especially in the photoreceptor on the belt. The photosensitive layer can also be coated with a layer that serves as a protective layer, if necessary.

The support used in the electrophotographic photoreceptor of the present invention may be any support as long as it is endowed with conductivity, and any type of conductive layer conventionally used may be used.

Specifically, metals such as aluminum, copper, stainless steel, and brass, plastics or conductive particles on which alumite indium oxide, tin oxide, etc. are vapor-deposited or laminated are used.
Examples include carbon blanks, plastics with tin particles, and aluminum particles dispersed therein. Regarding its shape, it may be a drum sheet or other shapes.

1. When using the electrophotographic photoreceptor according to the present invention, the light source is not only a normal halogen lamp but also a gallium-aluminum-arsenic semiconductor laser (oscillation wavelength 780 nm), which has a sensitivity of 750 nm or more. A laser beam can also be used.

The present invention will be explained below by giving one example.

In the examples, "parts" indicate parts by weight.

Example 1 40 parts of copper phthalocyanine and 0.5 part of jetoxy-dinitro copper phthalocyanine are dissolved in 500 parts of 98% concentrated sulfuric acid with thorough stirring. Pour the molten liquid into 5000 parts of water,
After the composition of copper phthalocyanine and jetoxy-dinitro copper phthalocyanine was precipitated, it was filtered for 9 times, washed with water, and then washed under reduced pressure for 1 time.
Dry at 20°C.

Next, 1 part of this composition, 2.5 parts of p-N-diethylaminobenzaldehyde-N, N-diphenylhydrazone
Part, acrylic polyol (manufactured by Takeda Pharmaceutical Co., Ltd.).

A composition consisting of 3.6 parts of Takelac UA-702), 0.5 parts of epoxy resin (Epon 1007 manufactured by Shell Chemical Co., Ltd.), 1.2 parts of methyl ethyl ketone, and 1.2 parts of cellosolve acetate was kneaded for 48 hours in a magnetic ball mill. A photoconductive composition is obtained.

Next, this photoconductive composition was roll coated onto the aluminum of a laminate film of 5 micron thick aluminum foil and 75 micron polyester film to a dry film thickness of 8 microns, and uniformly heated to 110°C. Place in the heated oven for 1 hour.

It was used as an electrophotographic photoreceptor. +5,7KV for the sample thus obtained, )O na gap 10mm, 10ff
Corona discharge was applied at a charging speed of l/win, and 10 seconds after the discharge stopped, a tungsten light source of 2854 was applied.
Expose with an illuminance of 0 Lux. The amount of light irradiation required for the potential immediately before exposure to decrease by 50% at this time was defined as the sensitivity.

The sample measured in this way had a maximum surface charge of 670
V, dark decay rate 16%, sensitivity 1.5 Lux.

The residual potential of SeC+ is 20V, which is sufficient for practical use in both chargeability and sensitivity.When its optical attenuation curve was measured, no induction was observed at 1 surface type attenuation upon charging exposure, and a 5-curve optical attenuation curve was obtained. showed that. In addition, 10,000 copies were continuously made using this photoreceptor using a copying machine with positive charging, but the resulting images had excellent gradation9. A beautiful image was obtained in terms of detail intermediate color density, and there was no change in sensitivity.Furthermore, although there were some scratches on the photoreceptor, the copied image was clear with no scratches at all. .

Also, for the same photoreceptor, +5.7KV, Corona Gi'r
Corona discharge was applied at a charging speed of r-/p10 ll1 m, 10 m/n+in, and after the discharge stopped, 780
The gallium-arsenide semiconductor is exposed to laser light having a wavelength of nm. The amount of light irradiation required for the potential immediately before exposure to decrease by 50% at this time was defined as the sensitivity. The sample measured in this way had a maximum surface charge of 67 ov and a dark decay rate of 16
%, sensitivity 0.7μJ/cd, residual potential 20V,
Chargeable.

Both sensitivities were sufficient for practical use.

Examples 2 to 7 The results of tests conducted in the same manner as in Example 1 are shown below, using phthalocyanines and phthalocyanine derivatives shown in Table 1 below instead of copper phthalocyanine and jetoxy-dinitro copper phthalocyanine.

(Left below) Example 8 40 parts of copper phthalocyanine, mononitro-trimethoxy-
1.5 parts of metal-free phthalocyanine to 1 part of 98% concentrated sulfuric acid
00 parts with sufficient stirring. Add the dissolved liquid to 5 liters of water.
After the phthalocyanine composition was precipitated, it was filtered once, washed with water, and dried at 120° C. under reduced pressure. Next, 1 part of this composition and 2 parts of 1-phenyl-3-(P-diethylaminostyryl)-5-(P-diethylaminophenyl)-2Δ-pyrazoline were added to 4 parts of polycarbonate resin (Kijin Panlite L-1250). was dispersed in a ball mill with 10 parts of tetrahydrofuran, and this liquid was sprayed onto an aluminum cylinder to a thickness of 10 microns and dried to form an electrophotographic photoreceptor. The electrophotographic properties of the thus obtained sample were measured in the same manner as in Example 1. The sample measured in this way had a maximum surface charge of 600 V, a sensitivity of 1.4 Lux, sec, and a light decay curve of 5
It exhibits a curved line, and even in a repeated live copy test using positive charging using a copying machine, the gradation was excellent in both the initial and final images after 10,000 copies.

Clear images were obtained with no change in sensitivity.

Example 9 Obtained in Example 1. Phthalocyanine composition 1
part, diethylaminophenyloxadiazole 2
parts, triphenylmethane 0.8 parts, acrylic resin 4 parts,
20 parts of cellosolve acetate was dispersed in a ball mill, and the sample was measured in the same manner as in Example 1.

The obtained light decay curve is 5 curves without induction, the maximum surface potential at this time is 610 V, and the dark decay rate is 12%.
, the sensitivity was 1.6 Lux, sec, and the residual potential was 15 V, and the same results as in Example 1 were obtained in the actual photographic test.

Example i.

After heating the phthalocyanine composition obtained in Example 1 in xylene for 6 hours, 1 part of this composition, 30 parts of cellosolve acetate, and 50 parts of steel beads were added to 70 c.
C. The phthalocyanine composition was placed in a mayonnaise bottle, pulverized in a paint shaker for 5 hours, and the solvent was removed under reduced pressure. Met. A photoreceptor was prepared using this phthalocyanine composition in the same manner as in Example 1. Corona discharge was applied to the sample thus obtained at a charging speed of +5.7 KV and a corona gap of 10 m/11 inch, and after 10 seconds after the discharge was stopped, it was exposed to light using a 2854 tungsten light source at an illuminance of 10 Lux. The amount of light irradiation required for the potential immediately before exposure to decrease by 50% at this time was defined as the sensitivity. The sample measured in this way has a maximum surface potential of 68 QV, a dark decay rate of 13%, and a sensitivity of 1.7 Lu.
x, 5eC9 residual potential is 30V, which is a value sufficient for practical use in both chargeability and sensitivity.The light attenuation curve shows no induction at 2 surface potential decay upon charging exposure, and shows a 3-curve light attenuation curve. Ta. I also used a copying machine to positively charge this photoreceptor and made too many copies in a row, but the resulting images had excellent gradation, and even when copies were made using an ordinary photograph as an original, Beautiful images can be obtained in terms of detail intermediate color density, there is no change in sensitivity, and
Although there were some scratches on the photoreceptor, a clear image without any scratches was obtained in the copied image.

A corona discharge is applied at a charging speed of a corona gap of 10 m/sin, and 10 seconds after the discharge is stopped, exposure is performed using a 2854 tungsten light source at an illumination intensity of 10 Lux. The amount of light irradiation required for the potential immediately before exposure to decrease by 50% at this time was defined as the sensitivity. The sample measured in this way has a maximum surface potential of 680 V, a dark decay rate of 13%, and a sensitivity of 1.7.
Lux, sec + residual potential 30V.

Both chargeability and sensitivity were of values sufficient for practical use, and the light attenuation curve showed no induction in one surface potential attenuation during charging exposure, and showed a three-curve light attenuation curve. In addition, 10,000 copies were continuously made using this photoconductor using a copying machine with positive charging, and the resulting images had excellent gradation1. A beautiful image was obtained in terms of detail intermediate color density, and there was no change in sensitivity.Furthermore, although there were some scratches on the photoreceptor, a clear image without any scratches was obtained in the copied image.

Example 11 1 part of ε-type copper phthalocyanine, 50 parts of cyclohexanone,
4 parts of polyester resin (manufactured by Toyobo, Byron 200),
Triamyloxy-mononitro copper phthalocyanine 0.0
The composition consisting of two parts is milled in a magnetic ball mill for 48 hours to obtain a photoconductive composition. Next, this photoconductive composition was roll coated onto the aluminum of a laminate film of a 5 micron thick aluminum foil and a 75 micron polyester film to a dry film thickness of 8 microns, and was uniformly heated to 100°C. The sample was placed in a heated oven for 1 hour to prepare an electrophotographic photoreceptor.

For the sample obtained in this way, +5°7K
V, Coronagi+7110 ma+, 10 m/w
Corona discharge is applied at a charging speed of in, and after the discharge stops,
After 10 seconds, 10 L with 2854 tungsten light source.
Expose at ux illuminance. The potential just before exposure at this time is 50
The amount of light irradiation required for the irradiation of the light required for the % reduction was defined as the sensitivity. The sample measured in this way had a maximum surface charge of 680 V, a dark decay rate of 15%, and a sensitivity of 1.8.
Lux, sec + residual potential 30V, chargeability,
Both the sensitivity and the value are sufficient for practical use, and the optical attenuation curve is
Upon charging exposure, no induction was observed at 9 surface potential attenuations, and a 3-curve light attenuation curve was shown. In addition, 10,000 copies were continuously made using this photoconductor using a copying machine with positive charging, and the resulting images had excellent gradation1. A beautiful image was obtained in terms of detail intermediate color density, and there was no change in sensitivity.Furthermore, although there were some scratches on the photoreceptor, a clear image without any scratches was obtained in the copied image.

Examples 12 to 14 In Example 11, the phthalocyanine derivatives shown in Table 2 were used instead of triamyloxy-mononitrocopper phthalocyanine, and the results were tested in the same manner as in Example 6.

(Margin below) Table 2 Snoring margin) Example 15 5 parts by weight of the phthalocyanine composition obtained in Example 1 and thermoplastic acrylic resin 0XL-97 (manufactured by Mikata Toatsu) 20
Parts by weight, butyl acetate/cellosolve acetate (1:1
) 30 parts by weight of the composition was kneaded in a ball mill for 24 hours to prepare a photoconductive coating, and this coating was coated on an aluminum support to a thickness of about 0.5 microns;
A charge generation layer was formed.

Next, 10 parts by weight of polycarbonate resin (manufactured by Kijin) and 5 parts by weight of polyester resin (manufactured by Gutsdoyer).

5 parts by weight of acrylic resin (manufactured by Mitsubishi Kasei) was dissolved in 150 parts by weight of tetrahydrofuran/toluene (9:1).

Next, 12 parts by weight of n-ethylcarbazole-2-cabaldehyde diphenylhydrazone was added to 0% silicone oil.
．． It was added together with 02 parts by weight. This liquid was applied to the charge generation layer to a thickness of about 15 microns, dried at 80 degrees,
A charge transport layer was formed to obtain a laminated photoreceptor.

For the sample thus obtained, −5°IK
V, coronagi +-/pu I Q IIIm, I Q t
Corona discharge is applied at a charging speed of s/win, and 10 seconds after the discharge is stopped, exposure is performed using a 2854 tungsten light source at an illuminance of 10 Lux. At this time, the amount of light irradiation required for the irradiation with the light required for the potential immediately before exposure to decrease by 50% was defined as the sensitivity. The sample measured in this way had a maximum surface charge of 650 V, a dark decay rate of 8%, a sensitivity of 1.5 Lux, sec, and a residual potential of 15 V, which are sufficient values for practical use in both chargeability and sensitivity. The attenuation curve showed no induction in the 2-surface type attenuation upon charging exposure, and showed a 5-curve light attenuation curve. Furthermore, 10,000 copies were continuously made of this photoreceptor using a copying machine with positive charging, and the resulting images had excellent gradation.
Even when copying an ordinary photograph as an original, a beautiful image is obtained in terms of detail and intermediate color density, and there is no change in sensitivity.Furthermore, although there are some scratches on the photoreceptor,
A clear image with no scratches was obtained in the copied image.

Comparative Example 1 Example 1 p-diethylaminobenzaldehyde-N,N
A photoreceptor was prepared according to Example 1 without adding 2.5 parts of -diphenylhydrazone. Furthermore, when the characteristics of the photoreceptor were measured under the same conditions as in the example, the maximum surface charge of this sample was 550V, the sensitivity was 2.4 Lux, and the sensitivity was 5eC1, but the optical attenuation curve (dotted line) is shown in Figure 1. like,
There was a lot of induction, and the light attenuation curve showed an inverted S-shaped curve.

Furthermore, in the photocopy test, scratches appeared from the 1000th sheet onwards, and the scratches were also rough in the copied images, which would pose a problem for practical use.

Comparative Example 2 A sample was prepared and tested in the same manner as in Example except that the phthalocyanine composition in Example 1 was replaced with β-type copper phthalocyanine (Lionol Blue SM, manufactured by Toyo Ink Manufacturing ■). The obtained results showed that the maximum surface potential was 600 μ, but the sensitivity was 20 Lux, sec.

This was insufficient for practical use.

"Effects of the Invention" The electrophotographic photoreceptor according to the present invention has no hygiene problems, and is superior to semiconductor laser light in the near-infrared region than visible light in both single-layer photoreceptors and 9-function separated photoreceptors. It has high sensitivity and also in two-image reproduction.

It has excellent gradation, and there is little deterioration of the photoreceptor due to repeated use, and in practical use, it is resistant to scratches on the photoreceptor.
The scratches will not appear on the copied image, which is an excellent feature for practical use.

Claims (1)

[Scope of Claims] 1. Phthalocyanine and the benzene nucleus of the phthalocyanine molecule is at least one electron-withdrawing group selected from a nitro group, a halogen atom, a sulfone group, a carboxyl group, and a trifluoromethyl group, an alkoxy group, and an aryloxy group. A phthalocyanine composition comprising a phthalocyanine derivative substituted with at least one electron-donating group selected from , an alkylthio group, and an aralkylthio group. 2. Phthalocyanine and the benzene nucleus of the phthalocyanine molecule is at least one electron-withdrawing group selected from a nitro group, a halogen atom, a sulfone group, a carboxyl group, and a trifluoromethyl group, and an alkoxy group, an aryloxy group, an alkylthio group, and an aralkylthio group. 1. An electrophotographic photoreceptor comprising a photosensitive layer containing a phthalocyanine derivative substituted with at least one electron-donating group selected from the group consisting of: