JP3125240B2 - Electrophotographic photoreceptor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor,
The present invention relates to an electrophotographic photosensitive member useful for a printer, a copying machine, and the like, and also suitable for forming an image using a semiconductor laser beam or the like as an exposure unit.

[0002]

2. Description of the Related Art In recent years, research on photoconductive materials has been actively conducted, and they have been applied to photoelectric conversion elements such as electrophotographic photosensitive members, solar cells, and image sensors.
Conventionally, inorganic materials are mainly used as these photoconductive materials. For example, in an electrophotographic photoreceptor, a photosensitive layer mainly composed of an inorganic photoconductive material such as selenium, zinc oxide, and cadmium sulfide is provided. Inorganic photoreceptors have been widely used.

However, such inorganic photoconductors have not always been satisfactory in characteristics such as photosensitivity, heat stability, moisture resistance and durability required for electrophotographic photoconductors such as copying machines and printers. For example, selenium is crystallized due to heat, stains on fingerprints, and the like, so that the characteristics of the electrophotographic photosensitive member are likely to deteriorate. Further, an electrophotographic photosensitive member using cadmium sulfide is inferior in moisture resistance and durability, and an electrophotographic photosensitive member using zinc oxide has a problem in durability.

[0004] In recent years, environmental issues have become particularly important, but electrophotographic photoreceptors such as selenium and cadmium sulfide have drawbacks in that their production and handling are greatly restricted in terms of toxicity.

[0005] In order to improve the disadvantages of such inorganic photoconductive materials, various organic photoconductive materials have attracted attention, and recent attempts have been made to use them for photosensitive layers of electrophotographic photoreceptors. Research is being actively conducted. For example, Japanese Patent Publication No. Sho 50-10496 describes an organic photoreceptor having a photosensitive layer containing polyvinyl carbazole and trinitrofluorenone. However, this photoreceptor is not sufficient in sensitivity and durability. Therefore, a function-separated type electrophotographic photoreceptor in which the carrier generation function and the carrier transport function are individually assigned to different substances has been developed.

In such an electrophotographic photoreceptor, since the material can be selected in a wide range, it is easy to obtain arbitrary characteristics.
Therefore, it is expected that an organic photoreceptor excellent in high sensitivity and high durability can be obtained.

Various organic compounds have been proposed as a carrier-generating substance and a carrier-transporting substance for such a function-separated type electrophotographic photoreceptor. In particular, the carrier-generating substance is important in controlling the basic characteristics of the photoreceptor. Functions. As the carrier-generating substance, photoconductive substances such as polycyclic quinone compounds represented by dibromoanthranthrone, pyrylium compounds and eutectic complexes of pyrylium compounds, squarium compounds, phthalocyanine compounds and azo compounds have been put to practical use. Was.

[0008] Among them, titanyl phthalocyanine having a specific crystal form is known to exhibit particularly excellent properties. Titanyl phthalocyanine has many crystals and shows completely different properties depending on the crystal type. Among them, a crystal having a maximum peak at a Bragg angle 2θ of 27.2 ° ± 0.2 ° in an X-ray diffraction spectrum for Cu-Kα ray. Since the type of titanyl phthalocyanine has remarkably high photon efficiency, electrophotographic photoreceptors using such titanyl phthalocyanine as a carrier-generating substance are extremely useful for designing high-speed printers, high-speed digital copiers, and high-speed facsimile machines. It has become.

However, when a compound having such a high quantum efficiency is used as a carrier-generating substance, it has a high sensitivity and responds to even a small amount of light. In this case, in the use environment, even a slight leak of light may be picked up as an image and become a defect. Further, for example, when a semiconductor laser is used as the exposure means, when a large amount of light is irradiated on the photoconductor due to a variation in irradiation light intensity, it is expected that the reproducibility of fine lines is affected. Also, it is desired to arbitrarily adjust the light attenuation characteristics of the photoconductor by the image forming process to be used. It was impossible to do. Further, by changing the combination of the carrier-generating substance and the carrier-transporting substance, not only the cost is increased but also the stability of the photoconductor during repeated use due to factors such as a difference in ionization potential may occur. From these points, there is a demand for a technique for adapting an electrophotographic photosensitive member to various image forming processes using a kind of photosensitive layer without impairing various characteristics required for the electrophotographic photosensitive member such as a repetition characteristic. .

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photoreceptor which overcomes the above-mentioned problems and has high sensitivity and is useful for use in a high-speed printer, a high-speed digital copying machine or a high-speed facsimile.

Another object of the present invention is to provide an electrophotographic photosensitive member having stable characteristics when used repeatedly.

A further object of the present invention is to provide excellent production stability,
An object of the present invention is to provide an electrophotographic photoreceptor having little characteristic fluctuation and excellent image characteristics.

[0013]

The object of the present invention is to provide an electrophotographic photoreceptor having a photosensitive layer and a protective layer sequentially laminated on a conductive support, wherein the transmittance of the protective layer to monochromatic light of 780 nm is improved. 90% or less, and the protective layer contains the infrared absorbing dye in an amount of 0.001 to 1% by weight based on the binder of the protective layer,
The infrared absorbing dye is naphthalocyanine, and a latent image is formed by a semiconductor laser.

In the present invention, naphthalocyanine compounds are particularly used because they exhibit sharp absorption around 780 nm and have excellent potential stability when used repeatedly.

With respect to naphthalocyanine, naphthalocyanine of various central metals has already been known. For example, Japanese Patent Application Laid-Open No. 63-55556 discloses that naphthalocyanine is used as a carrier-generating substance in a laminated photoreceptor. However, in the photoreceptor of the present invention, the infrared-absorbing naphthalocyanine is completely different in that it does not have a function on sensitivity due to generation of a carrier, and further exhibits its function in a protective layer instead of a carrier generation layer.

The naphthalocyanine used in the present invention is represented by the following general formula [2].

[0017]

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In the formula, M represents a hydrogen atom or a metal atom, preferably Si, Ge, Sn, Cu, Zn, Mg, Ti,
V, Al, In and the like. Y represents a substituted or unsubstituted alkyl group, alkoxy group, aryloxy group, halogen atom, oxygen atom, siloxy group, or hydroxyl group; X ¹ , X ² , X ³ , and X ⁴ represent a hydrogen atom, a halogen atom, Represents an alkyl group, an alkoxy group, or an aryloxy group.

Further, the naphthalocyanine compound used in the present invention is preferably a naphthalocyanine having high solubility in an organic solvent or various binders when used in a form dissolved in a binder in the protective layer. Those having a large number of alkyl groups in the molecule have high solubility and preferably have an alkyl group having 6 or more carbon atoms.

Therefore, in the naphthalocyanine represented by the general formula [2], M, Y and X are specified, and the silicon naphthalocyanine represented by the general formula [1] shown in the above formula 1 is particularly preferable. .

These silicon naphthalocyanines can be synthesized according to the method described in J. Am, Chem. Soc., 106, 7404 (1984).

The following are specific examples of the naphthalocyanine used in the present invention.

[0023]

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[0024]

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[0025]

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[0026]

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The carrier-generating substance used in the present invention may be any substance which has sensitivity to LD light, and specific examples thereof include crystalline non-metallic phthalocyanine such as α, β, τ, X, and A. , B, and C, amorphous and black crystals having a maximum peak at 27.2 ° of 27.2 °, titanyl phthalocyanine, a mixed crystal of a plurality of phthalocyanines represented by a mixed crystal of titanyl phthalocyanine and vanadyl phthalocyanine, and a copper phthalocyanine. Metal phthalocyanine, naphthalocyanine, other porphyrin derivatives, azo compounds, polycyclic quinone compounds represented by dibromoanthranthrone, pyrylium compounds and eutectic complexes of pyrylium compounds, squarium compounds, among others. Titanylph with maximum peak at 27.2 ° ± 0.2 of 2θ Roshianin is preferred,
In addition, Bragg angle 2θ (± 0.2 °) of 9.5 °, 24.1 °, 27.2
Titanyl phthalocyanine having a peak at ° is most preferred.

The X-ray diffraction spectrum is measured under the following conditions, where the peak is a sharp acute-angle projection different from noise.

X-ray tube Cu voltage 40.0 KV current 100 mA Start angle 6.0 deg. Stop angle 35.0 deg. Step angle 0.02 deg. Measurement time 0.50 sec. The electrophotographic photoreceptor of the present invention may use the above carrier-generating substance in combination.

Next, various carriers can be used as the carrier transporting material used in the electrophotographic photoreceptor of the present invention. Representative examples thereof include oxazole, oxadiazole, thiazole, thiadiazole and imidazole. Having a nitrogen-containing heterocyclic nucleus and a condensed ring nucleus, a polyarylalkane compound, a pyrazoline compound, a hydrazone compound, a triarylamine compound, a styryl compound, a poly (bis) styryl compound, styryltriphenyl Examples include amine compounds, β-phenylstyrylphenylamine compounds, butadiene compounds, hexatriene compounds, carbazole compounds, condensed polycyclic compounds, and the like. Specific examples of these carrier transporting materials include, for example, the carrier transporting materials described in JP-A-61-107356. Particularly representative structures are shown below.

[0031]

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[0032]

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[0033]

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[0034]

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[0035]

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[0036]

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Various configurations of the photosensitive member are known. The photoreceptor of the present invention can take any of these forms, but usually has a configuration as shown in (1) to (8) of FIG.

In the layer configuration shown in (1), a carrier generation layer 2 is formed on a conductive support 1 and a carrier transport layer 3
Are laminated to form a photosensitive layer 4, and (2) is a photosensitive layer 4 'formed by reversing the carrier generation layer 2 and the carrier transport layer 3. (3) has an intermediate layer 5 provided between the photosensitive layer 4 having the layer constitution of (1) and the conductive support 1. The layer configuration of (5) is obtained by forming a photosensitive layer 4 ″ containing a carrier-generating substance 6 and a carrier-transporting substance 7, and (6) is a section between the photosensitive layer 4 ″ and the conductive support 1. In which an intermediate layer 5 is provided. The layer configuration of (7) is such that the carrier generation layer 2 is provided on one conductive support, and (8) is that the intermediate layer 5 is provided between the carrier generation layer 2 and the conductive support 1. Things. These (1)
In the configurations (1) to (8), a protective layer 8 having a transmittance of 90% or less for monochromatic light of 780 nm is provided on the outermost layer.

In forming the photosensitive layer, it is effective to apply a solution in which a carrier-generating substance or a carrier-transporting substance is dissolved alone or together with a binder or an additive. However, since the solubility of the carrier-generating substance is generally low, in such a case, the carrier-generating substance is transferred to an ultrasonic disperser,
It is effective to apply a liquid in which fine particles are dispersed in an appropriate dispersion medium using a dispersing device such as a ball mill, a sand mill, and a homomixer. In this case, the binder and the additive are usually used by adding to the dispersion.

A wide variety of solvents or dispersion media can be used for forming the photosensitive layer. For example, butylamine, ethylenediamine, N, N-dimethylformamide, acetone, methyl ethyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, cyclohexanone, 4-methoxy-4-methyl-2-pentanone, tetrahydrofuran, dioxane, ethyl acetate, butyl acetate,
Examples include t-butyl acetate, methyl cellosolve, ethyl cellosolve, butyl cellosolve, ethylene glycol dimethyl ether, toluene, xylene, acetophenone, chloroform, dichloromethane, dichloroethane, trichloroethane, methanol, ethanol, propanol, and butanol.

When a binder is used for forming the carrier generation layer or the carrier transport layer, any binder can be selected, but a high molecular polymer which is particularly hydrophobic and has a film forming ability is desirable. Examples of such a polymer include the following,
It is not limited to these. Polycarbonate Polycarbonate Z resin Acrylic resin Methacryl resin Polyvinyl chloride Polyvinylidene chloride Polystyrene Styrene-butadiene copolymer Polyvinyl acetate Polyvinyl formal Polyvinyl butyral Polyvinyl acetal Polyvinyl carbazole Styrene-alkyd resin Silicone resin Silicone-alkyd resin Silicone-butyral resin Polyester Polyurethane Polyamide Polyamide Polyamide Epoxy Resin Phenol resin Vinylidene chloride-acrylonitrile copolymer Vinyl chloride-vinyl acetate copolymer Vinyl chloride-vinyl acetate-maleic anhydride copolymer The ratio of the carrier-generating substance to the binder is preferably 10 to 600% by weight, and more preferably 50 to 50% by weight. Desirably, it is set to about 400% by weight. The ratio of carrier transport material to binder is
It is desirable that the content be 10 to 500% by weight. The thickness of the carrier generation layer is set to 0.01 to 20 μm, preferably 0.05 to 5 μm. The thickness of the carrier transport layer is from 1 to 100 μm, preferably from 5 to 30 μm.

Next, in the present invention, a protective layer is provided on the photosensitive layer. As the resin used for the protective layer, any of thermoplastic and thermosetting resins can be used. May be used in combination. Examples of the resin used for the protective layer include the carrier generation layer and the resin used for the carrier transport layer.
In addition, polycondensation type and addition polymerization type thermosetting resins can be used. Phenol resin, urea resin, melamine resin, phenol resin, guanamine resin,
And the addition polymerization type includes unsaturated polyester resin, alkyl resin, diallyl phthalate resin, epoxy resin and polybutadiene resin.

It should be noted that other resins may be used in combination as long as the performance is not impaired.

The ratio of the infrared absorbing dye to the binder in the protective layer is 0.0001 to 10% by weight, particularly preferably 0.001 to 10% by weight.
１1% by weight. The thickness of the protective layer is from 1 to 100 μm, preferably from 3 to 20 μm. Further, a carrier transporting material may be contained in the protective layer as needed.

The photosensitive layer may contain an electron-accepting substance for the purpose of improving the sensitivity, reducing the residual potential, or reducing fatigue upon repeated use. Such electron accepting substances include, for example, succinic anhydride, maleic anhydride,
Dibromo succinic anhydride, phthalic anhydride, tetrachloro phthalic anhydride, tetrabromo phthalic anhydride, 3-nitro phthalic anhydride, 4-nitro phthalic anhydride, pyromellitic anhydride,
Melitic anhydride, tetracyanoethylene, tetracyanoquinodimethane, o-dinitrobenzene, m-dinitrobenzene, 1,3,5-trinitrobenzene, p-nitrobenzonitrile, picryl chloride, quinone chlorimide, chloranil, bromanil , Dichlorodicyano-p-benzoquinone, anthraquinone, dinitroanthraquinone, 9-fluorenylidenemalononitrile, polynitro-9-fluorenylidenemalononitrile, picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, 3,5 -Dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, phthalic acid, melitic acid, and other compounds having a high electron affinity. The addition ratio of the electron-accepting substance is 0.0
It is preferably from 1 to 200, and more preferably from 0.1 to 100.

Further, the above photosensitive layer contains storability, durability,
For the purpose of improving environmental resistance, a deterioration inhibitor such as an antioxidant or a light stabilizer can be contained. Compounds used for such purposes include, for example, chromanol derivatives such as tocopherol and etherified or esterified compounds thereof, polyarylalkane compounds,
Hydroquinone derivatives and their mono- and dietherified compounds, benzophenone derivatives, benzotriazole derivatives, thioether compounds, phosphonate esters, phosphite esters, phenylenediamine derivatives, phenol compounds, hindered phenol compounds, linear amine compounds,
A cyclic amine compound, a hindered amine compound and the like are effective. Specific examples of particularly effective compounds include "IRGANOX
1010 ”,“ IRGANOX 565 ”(manufactured by Ciba-Geigy),“ Sumilyzer BHT ”,“ Sumilyzer MDP ”(manufactured by Sumitomo Chemical Co., Ltd.)
Hindered phenol compounds such as “Sanol LS-262
And "Sanol LS-622LD" (manufactured by Sankyo).

As the binder used for the intermediate layer, the protective layer and the like, those mentioned above for the carrier generating layer and the carrier transporting layer can be used. In addition, nylon resin, ethylene-vinyl acetate copolymer, Ethylene resins such as ethylene-vinyl acetate-maleic anhydride copolymer and ethylene-vinyl acetate-methacrylic acid copolymer, polyvinyl alcohol, and cellulose derivatives are effective.
Further, a curable binder utilizing thermal curing or chemical curing of melamine, epoxy, isocyanate or the like can be used.

As the conductive support, a metal plate or a metal drum may be used, or a conductive polymer such as a conductive polymer or indium oxide, or a thin layer of a metal such as aluminum or palladium may be applied, vapor-deposited or laminated. Thus, a material provided on a substrate such as paper or a plastic film can be used.

[0049]

Next, the present invention will be described in detail with reference to examples.

Examples 1 to 3 100 parts by weight of methyl ethyl ketone and 1 part by weight of polyvinyl butyral resin were added to 1 part by weight of titanyl phthalocyanine having peaks at Bragg angles 2θ of 9.5 °, 24.1 ° and 27.2 ° in FIG. And dispersed. After evaporating a part of the obtained dispersion to dryness, the X-ray diffraction spectrum was measured, as shown in FIG.

On the other hand, a 0.3 μm-thick subbing layer made of polyamide resin “CM-8000” (manufactured by Toray Industries, Inc.) was provided on a polyester base on which aluminum was deposited by a wire bar coating method. Was coated with a wire bar to form a carrier generation layer having a thickness of 0.2 μm. Next, 1 part by weight of a carrier transporting substance (21), 1.33 parts by weight of a polycarbonate resin "Iupilon Z-200" (manufactured by Mitsubishi Gas Chemical Company), and a small amount of silicone oil "KF-54" (manufactured by Shin-Etsu Chemical Co., Ltd.)
Was dissolved in 8 parts by weight of 1,2-dichloroethane to form a 20 μm-thick carrier transport layer by blade coating.
Further, 1 part by weight of a polycarbonate resin “Iupilon Z-200” (manufactured by Mitsubishi Gas Chemical Company) and silicon naphthalocyanine (2) were added to 6 parts by weight of 1,2-dichloroethane and dissolved, and then this liquid was transferred to a carrier transport layer. Apply on top and thickness 5μ
m protective layer. The photoconductors thus obtained are referred to as Samples 1 to 3.

Example 4 A photoconductor of the present invention was obtained in the same manner as in Example 3, except that a silicone-butyral resin was used in place of the polyvinyl butyral resin. This is designated as Sample 4.

Example 5 A photoconductor was prepared by the same way as that of Example 4 except that 1 part by weight of 1,4-butanediol was added to the dispersion obtained in Example 4. This is designated as Sample 5.

Example 6 The same as Example 3 except that titanyl phthalocyanine in Example 3 was changed to titanyl phthalocyanine showing X-ray diffraction spectra having peaks at Bragg angles 2θ of 27.2 °, 24.1 ° and 9.0 ° in FIG. Thus, the photoreceptor of the present invention was obtained.
This is designated as Sample 6.

Comparative Example (1) A comparative photoreceptor was obtained in the same manner as in Example 1 except that silicon naphthalocyanine was omitted. These are designated as Comparative Sample (1).

Comparative Example (2) A comparative photoreceptor was obtained in the same manner as in Example 5, except that silicon naphthalocyanine was omitted. These are designated as Comparative Sample (2).

Comparative Example (3) A comparative photoreceptor was obtained in the same manner as in Example 6, except that silicon naphthalocyanine in the present invention was omitted. These are designated as Comparative Sample (3).

Examples 7 and 8 On a polyester base on which aluminum was vapor-deposited, a 0.1 μm-thick film made of a vinyl chloride-vinyl acetate-maleic anhydride copolymer (Eslec MF-10: manufactured by Sekisui Chemical Co., Ltd.)
Was formed. Next, the carrier transport material (2) /
A 1,2-dichloroethane solution containing 16.5% of a polycarbonate resin (Panlite L-1250, manufactured by Teijin Chemicals Ltd.) = 75/100 (weight ratio) is dip-coated on the intermediate layer, dried and transported to a carrier having a thickness of 15 μm. Layer obtained.

Next, the Bragg angle 2θ of 9.5 ° in FIG.
To 1 part by weight of titanyl phthalocyanine having peaks at 1 ° and 27.2 °, 30 parts by weight of methyl ethyl ketone and 1 part by weight of a polyvinyl butyral resin were added and dispersed using a sand mill. After evaporating a part of the obtained dispersion to dryness, the X-ray diffraction spectrum was measured, as shown in FIG. This dispersion was coated on the carrier transporting layer to form a 1 μm-thick photosensitive layer by a spray coating method.

Further, 2,4,7-trinitro-9-fluorenone was pulverized by a ball mill for 24 hours.
3 parts by weight of a solution consisting of 100 parts by weight of 1,2-dichloroethane, 1 part by weight of an antioxidant "Sanol LS2626" (manufactured by Sankyo), 2 parts by weight of a carrier transporting substance (2) and silicon Phthalocyanine (1) was added to obtain a dispersion.

Even if monochlorobenzene is added to this dispersion, monochlorobenzene / 1,2-dichloroethane = 3/7
(Volume ratio) A protective layer having a thickness of 5 μm was formed on the photosensitive layer by a spray coating method to obtain a photosensitive member sample of the present invention having a laminated photosensitive member layer. These are designated as Sample 7 and Sample 8.

Comparative Example (4) A comparative photoreceptor was obtained in the same manner as in Example 7, except that silicon naphthalocyanine was omitted. These are designated as Comparative Sample (4).

Examples 9 and 10 4 parts by weight of titanyl phthalocyanine having peaks at Bragg angles 2θ of 9.5 °, 24.1 ° and 27.2 ° in FIG. 2, polyester resin (“Almatex P-645” manufactured by Mitsui Toatsu Chemicals, Inc.) 8 parts by weight, 2 parts by weight of a melamine resin (“Uban 21R” manufactured by Mitsui Toatsu Chemicals, Inc.) and 90 parts of cyclohexanone were dispersed using a sand mill to obtain a dispersion. This dispersion was coated on a polyester base on which aluminum was deposited by a blade and then heat-treated at 120 ° C. for 1 hour to obtain a photosensitive layer having a thickness of 15 μm.

Next, the polycarbonate resin “Iupilon”
1.33 parts by weight of Z-200 ”(Mitsubishi Gas Chemical Co., Ltd.) and a small amount of silicone oil“ KF-54 ”(Shin-Etsu Chemical Co., Ltd.)
Silicon naphthalocyanine (2) was added to and dissolved in a liquid dissolved in 8 parts by weight of dichloroethane, and this liquid was applied on a photosensitive layer to form a protective layer having a thickness of 5 μm. The photoconductors thus obtained are referred to as samples 9 and 10.

Comparative Example (5) A photoconductor was prepared by the same way as that of Example 9 except that silicon naphthalocyanine in the protective layer was removed.
This is designated as Comparative Sample (5).

Evaluation 1 The transmittance T of the protective layer of the obtained sample to 780 nm light
(%) Was measured.

Evaluation 2 The obtained sample was subjected to “Koni” in an environment of 20 ° C. and 50% RH.
ca 9028 "(manufactured by Konica Corp., a semiconductor laser light source used) is mounted on a modified machine, to adjust the grid voltage V _G to 600V, the potential V _L of the exposed portion at the time of light irradiation of the non-exposed portion potential V _H and 0.7mW It was measured. Next, the sample was transferred to an environment of 10 ° C. and 20% RH and sufficiently adjusted to the environment, and then V _H and V _L were measured under the above-described conditions. V _H and V _L after repeated use of 10,000 prints in an environment of 10 ° C. and 20% RH were also measured.

Evaluation 3 The sample was also left for one week in an atmosphere of 55 ° C. and 80% RH, and then mounted on a modified machine of “Konica 9028” in an environment of 20 ° C. and 50% RH to obtain V _H and V _L. Was measured.

Table 1 shows the results of the evaluation. The photoreceptor of the present invention has a remarkable effect on humidity fluctuation, reduction in change in photoreceptor characteristics due to repeated use, stabilization of a dispersion and a photoreceptor, and is suitable for use depending on the added amount of an infrared absorbing dye used. A photosensitive member having sensitivity can be obtained.

[0070]

[Table 1]

Evaluation 4 Examples 9 and 10 were applied to a modified machine of “Konica 9028” (manufactured by Konica).
And the photoreceptor obtained in Comparative Example 5 was mounted. After charging these samples, a laser beam having a wavelength of 780 nm was irradiated with varying amounts of light, and the surface potential after 0.7 seconds was measured. The results are shown in FIG.

In the present invention, even in a single-layer photoreceptor, the light quantity dependency can be changed without impairing the characteristics and without changing the material by the addition amount of naphthalocyanine in the protective layer. That is, it was confirmed that it was possible to provide a photosensitive member having a sensitivity according to the application without changing the material.

[0073]

According to the constitution of the present invention, it is possible to adjust the light attenuation characteristics to desired characteristics without changing the carrier generating material and the carrier transporting material and without impairing various characteristics required for the electrophotographic photosensitive member. It has become possible. Furthermore, the electrophotographic photoreceptor of the present invention is stable under various environments and can greatly improve the potential stability when used repeatedly.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an electrophotographic photosensitive member of the present invention.

FIG. 2 is an X-ray diffraction spectrum of titanyl phthalocyanine used in Example 1.

FIG. 3 shows X after evaporating a dispersion to dryness in Example 1.
Line diffraction spectrum diagram.

FIG. 4 is an X-ray diffraction spectrum of titanyl phthalocyanine used in Example 6.

FIG. 5 is a graph showing the relationship between the irradiation light amount and the surface potential obtained in Evaluation 4.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1 'Conductive support 2 Carrier generating layer 3 Carrier transport layer 4, 4' Photosensitive layer 5 Intermediate layer 6 Carrier generating substance 7 Carrier transporting substance 8 Protective layer

Continuation of the front page (56) References JP-A-63-235951 (JP, A) JP-A-61-34549 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 5 / 00

Claims (4)

(57) [Claims] 1. An electrophotographic photosensitive member in which a photosensitive layer and a protective layer are sequentially laminated on a conductive support.
The protective layer has an transmittance of 90% or less for monochromatic light of 0 nm, and the protective layer contains an infrared-absorbing dye in an amount of 0.000
1 to 1% by weight, and the infrared-absorbing dye is naphthalocyanine.
An electrophotographic photosensitive member , wherein a latent image is formed by a semiconductor laser. 2. The method according to claim 1, wherein the naphthalocyanine has the following general formula:
Be a silicon naphthalocyanine represented by [1]
The electrophotographic photosensitive member according to claim 1, wherein: Embedded image [ Wherein , Y is a (Rn) ₃ SiO- group (Rn is an alkyl group or an aryl group )
And at least one of Rn has 6 or more carbon atoms
X ¹ , X ² , X ³ and X ⁴ represent a hydrogen atom,
Halogen atom, alkyl group or alkoxy group, ant
Represents a hydroxy group. ] 3. A phthalocyanine as a carrier-generating substance.
The composition according to any one of claims 1 to 2, wherein
The electrophotographic photosensitive member according to the above. 4. A Cu-Kα ray (wavelength)
1.541Å), the maximum peak at 27.2 ° of Bragg angle 2θ
Containing titanyl phthalocyanine having
An electrophotographic photosensitive device according to any one of claims 1 to 3,
body.