JP2000075528A - Electrophotographic photoreceptor for interferable light and image forming method and apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a photoreceptor capable of stably obtaining a good image without causing any moire due to the interference fringes of laser beams and any cleaning defect by irradiating the surface of a substrate with laser beams to have the substrate whose surface is roughened in a specified range. SOLUTION: This apparatus is provided with a substrate whose surface Rz is roughened to 0.5-3 μm by irradiating it with laser beams. In this treatment for roughening the surface of the substrate, by fitting the drum-shaped substrate 2 to the chucking device 3 of a section 1 to be processed, its rotation is started at a prescribed revolution velocity by a driving power source 5 provided on a rotary shaft 4 of the substrate 2. Then, the laser beam oscillating source 8 of a laser beam processing section 6 is driven, the rotary drum-shaped substrate 2 is irradiated with laser beams emitted from a laser beam emitter 10b through a light guide tube 9 and a scanner 10a and the surface of the drum- shaped substrate 2 is roughened to surface roughness Rz of 0.5-3 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member for coherent light having a substrate whose surface is roughened by a laser beam, and an image forming method using the electrophotographic photosensitive member for coherent light. And an image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, an electrophotographic photoreceptor (hereinafter, also simply referred to as a photoreceptor) is made of, for example, pulverized aluminum,
It is obtained by subjecting a metal tube such as steel to grinding with a rotary grindstone, sand blasting, or cutting with a cemented carbide tool, single crystal diamond tool, polycrystalline diamond tool, etc. to roughen or mirror the surface. The photosensitive layer is obtained by providing a photosensitive layer via an intermediate layer of, for example, polyvinyl alcohol, polyamide resin, or the like on the substrate. However, when the surface of the above substrate is processed by a processing method such as polishing or cutting, troublesome skill is required, yield is poor, it is difficult to maintain and maintain processing accuracy, and a substrate having a desired surface roughness can be stably obtained. I couldn't do that.

On the other hand, a photosensitive member obtained by providing an organic photosensitive layer on the above substrate is used, and a semiconductor laser or He-Ne is used.
Image forming apparatuses such as digital copying machines and printers using coherent light such as lasers are regarded as important, and in the photoreceptor, uniform and specific images are prevented to prevent image deterioration such as moire caused by interference fringes. There is a need for a substrate having a surface roughness.

For example, Japanese Patent Application Laid-Open No. 63-64055 discloses a photoreceptor having an inorganic photosensitive layer by processing a substrate with a carbon dioxide laser beam to a surface roughness of 0.01 to 1.0 μm. A processing method for obtaining a substrate for use has been proposed. In addition, Japanese Patent Application Laid-Open No. H7-239563 (publication 2)
Has proposed a processing method for processing a substrate with a laser beam to a surface roughness of 8 to 20 μm to obtain a substrate for a photoreceptor having an organic photosensitive layer.

[0005]

However, in the above publications 1 and 2, since the surface roughness of the substrate processed by the laser beam is not appropriate, a photosensitive member obtained by providing a photosensitive layer on the substrate, especially an organic photosensitive member, is preferred. When an image is formed by irradiating a photoreceptor obtained by providing a layer with a laser beam modulated by image information, moire based on interference fringes of coherent light such as the laser beam occurs, or the moire is good. Even so, there is another problem, for example, a problem that a cleaning failure or the like occurs and the image is deteriorated, so that a good image cannot be obtained. Furthermore, in the photoreceptor having the above-mentioned organic photoreceptor layer, when repeatedly used for image formation depending on the kind of the charge generating substance contained in the photoreceptor layer of the photoreceptor, the electrophotographic property is significantly deteriorated due to fatigue deterioration. There is a problem of doing.

The present invention has been proposed in view of the above circumstances, and has as its object to provide an organic photosensitive layer on a substrate,
In particular, an image was formed by irradiating a coherent light such as a laser beam modulated by image information to a photoreceptor obtained by providing an organic photosensitive layer using Y-type titanyl phthalocyanine or imidazoperylene as a charge generating substance. When using a coherent light photoreceptor, the coherent light photoreceptor capable of stably obtaining a good image without generating moiré based on interference fringes of the laser beam, and without generating cleaning failure. An image forming method and an image forming apparatus are provided.

[0007]

The above object is achieved by the following constitution.

[0008] 1. Irradiation of laser beam to surface roughness R
An electrophotographic photoreceptor for coherent light, comprising a substrate having a surface roughness z of 0.5 to 3 μm.

[0009] 2. 2. The electrophotographic photoreceptor for coherent light as described in 1 above, which has a photosensitive layer using Y-type titanyl phthalocyanine or imidazoperylene as a charge generating substance.

[0010] 3. Irradiation of laser beam to surface roughness R
An image forming method using an electrophotographic photoreceptor for coherent light having a substrate whose z is roughened to 0.5 to 3 μm.

4. 4. The image forming method according to the above item 3, wherein an electrophotographic photoreceptor for coherent light having a photosensitive layer using Y-type titanyl phthalocyanine or imidazoperylene as a charge generating substance is used.

5. Irradiation of laser beam to surface roughness R
An image forming apparatus using an electrophotographic photoreceptor for coherent light having a substrate whose z is roughened to 0.5 to 3 μm.

6. 6. The image forming apparatus according to 5, wherein an electrophotographic photoreceptor for coherent light having a photosensitive layer using Y-type titanyl phthalocyanine or imidazoperylene as a charge generating substance is used.

Hereinafter, the present invention will be described in detail.

[Coherent Light Photoreceptor] The coherent light photoreceptor of the present invention comprises a photosensitive layer, particularly an organic photosensitive layer, on a substrate which has been subjected to a surface roughening treatment by a surface roughening method using a laser beam. It is obtained by providing a layer, an intermediate layer may be provided on the substrate, and a protective layer may be provided on the surface of the organic photosensitive layer.

<Substrate> The substrate used in the photoreceptor of the present invention may be a sheet, belt or drum-shaped substrate made of a material such as aluminum, magnesium, steel or plastic. The surface roughness is determined by the following surface roughening method using a high-energy cutting laser beam to be described later, which is emitted from a solid laser device such as a ruby laser or a semiconductor laser or a gas laser device such as a He-Ne laser or a carbon dioxide gas laser. Rz is roughened to 0.5 to 3 μm. When the surface roughness Rz of the obtained substrate is less than 0.5 μm, when an image is formed by a digital method using coherent light on a photoreceptor obtained by providing an organic photosensitive layer on the substrate, moire is generated. Occurs and the image deteriorates. Further, when the surface roughness Rz of the substrate of the photoreceptor exceeds 3 μm, black streaks due to poor cleaning during image formation and toner contamination occur.
In addition, the quality of the image is so poor that a high quality image cannot be obtained. In addition,
The surface roughness Rz is measured based on JIS B0601.

When the substrate is a high-resistance material such as plastic, a layer of a conductive compound such as a conductive polymer, indium oxide, tin oxide or ITO is provided on the substrate by coating or vapor deposition. Is imparted.

<Method for Roughening Surface of Substrate> The method for roughening the substrate according to the present invention will be described below with reference to FIG. FIG. 1 is an example of a surface roughening apparatus for explaining the surface roughening method using the laser beam. In the figure, reference numeral 1 denotes a portion to be processed, where 2 is a drum-shaped substrate, 3 is a chuck device, Reference numeral 4 denotes a rotating shaft, 5 denotes a drive source, 6 denotes a laser processing unit, and 7 denotes a guide rail, 8 denotes a laser oscillation source, 9 denotes a light guide tube, 10a denotes a scanner, and 10b denotes a laser. It is a beam emitting unit.

First, the drum-shaped substrate 2 is mounted on the chuck device 3 of the workpiece 1, and the drum-shaped substrate 2 is started to rotate at 200 to 500 rpm by the drive source 5 provided on the rotating shaft 4. Next, the laser oscillation source 8 of the laser processing section 6 is driven to drive the laser beam emitting section 10b to the light guide tube 9 from the laser beam emitting section 10b.
A laser beam is applied to the rotating drum-shaped substrate 2 via the scanner 10a to roughen the surface of the drum-shaped substrate 2 to a surface roughness Rz of 0.5 to 3.0 μm specific to the present invention. . At this time, the specific surface roughness Rz of the present invention is set to 0.1.
Laser beam emitting unit 1 to achieve 5-3.0 μm
The intensity of the laser beam irradiated from 0b is 2 × 10 ⁷
~ 2 × 10 ⁸ W / cm ² , beam diameter 10 ~ 500μ
m, and the scanner 10a is moved along the guide rail 7 by 0.2
Run at a speed of 走 行 7 mm / sec to roughen the surface.

<Photosensitive layer> The photosensitive layer provided on the substrate for producing the photoreceptor of the present invention is a photosensitive layer for coherent light, and may be either an inorganic photosensitive layer or an organic photosensitive layer.
Particularly preferred is an organic photosensitive layer.

FIG. 2 is a diagram showing the layer structure of the photosensitive layer in the above-mentioned photoreceptor, and various layer structures illustrated in FIGS. 2 (1) to (7) can be employed. In the above photoconductor,
2 (1) to 2 (5) show CGL (charge generation layer) 12 containing CGM (charge generation substance) and CTM (charge generation layer) on a conductive substrate 11 roughened to a degree of surface roughening peculiar to the present invention. FIG. 2 shows a structure in which a photosensitive layer 14 composed of a laminate with a CTL (charge transport layer) 13 containing a charge transport material is provided.
(3) to (5) show examples in which the photosensitive layer 14 is provided on the conductive substrate 11 with an intermediate layer 15 interposed therebetween.
(2) and (4) have CTL13 as the lower layer and CGL12
Is a two-layered photosensitive member having an upper layer. Furthermore, FIG.
(5) The upper layer CTL 131 and the lower layer CT as the CTL 13
This is a photoconductor having a CTL of a lamination type with L132. When the photosensitive layer 14 has a laminated structure as described above, a photosensitive member having excellent electrophotographic characteristics can be obtained. FIGS. 6 and 7 show layers 1 containing CTM as a main component.
6 is a photosensitive member having a photosensitive layer 14 containing CGM 17, and further has an intermediate layer 15 in FIG.

When the photosensitive layer 14 has a laminated structure as shown in FIGS.
L12 can be formed by the following method directly on the conductive substrate 11 or the CTL 13 to which conductivity has been imparted by a method described later, or via an intermediate layer 15 for adhesion or blocking as required. it can.

(1) Vacuum evaporation method.

(2) A method of applying a solution in which CGM is dissolved in an appropriate solvent.

(3) A method in which CGM is made into fine particles in a dispersion medium by a ball mill, a sand grinder or the like, and a dispersion obtained by mixing and dispersing with a binder, if necessary, is applied. Specifically, vacuum deposition, sputtering, CVD
Etc. or a coating method such as dipping, spraying, blade, roll or the like can be arbitrarily used.
The thickness of the CGL 12 thus formed is 0.01
To 5 μm, more preferably 0.0 to 5 μm.
5 to 3 μm, and the CGL 12 is usually CG in the form of fine particles.
It is formed by dispersing 1 part by weight of M into 5 parts by weight or less of a binder resin.

Although the thickness of the CTL 13 can be changed as required, it is usually preferably 5 to 30 μm.
Usually, it is formed by mixing and dissolving 0.1 to 5 parts by weight of a binder resin with respect to 1 part by weight of the CTL 13.

<< CGM >> Examples of CGM contained in the photosensitive layer of the photoreceptor include azo dyes, perylene dyes, indigo dyes, polycyclic quinone dyes, quinacridone dyes, bisbenzimidazole dyes, and indigo dyes. Dunthrone dyes, squarylium dyes, metal phthalocyanine pigments, metal-free phthalocyanine pigments, pyrylium salt dyes, thiapyrylium salt dyes and the like are used,
A Y titanyl phthalocyanine compound represented by the following general formula (1) is preferably used.

[0028]

Embedded image

In the formula, X ¹ , X ² , X ³ and X ⁴ each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, and n, m, l and k each represent an integer of 0 to 4,
The crystal type is Y type, and in the X-ray diffraction spectrum with respect to Cu-Kα ray, the Bragg angle 2θ of 9.6 ° ± 0.2
°, 24.1 ° ± 0.2 °, and 27.2 ° ± 0.2 °.

Among the Y titanyl phthalocyanine compounds of the above general formula (1), those in which X ¹ , X ² , X ³ and X ⁴ are hydrogen atoms are preferably used.
It is synthesized by the synthesis method described in JP-A-66641.

Further, as the CGM contained in the photosensitive layer of the photosensitive member, an imidazoperylene compound represented by the following general formula (2) or (3) is used.

[0032]

Embedded image

In the formula, Z represents an atomic group necessary for forming a substituted or unsubstituted aromatic ring, and is preferably a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a pyridine ring, a pyrimidine ring. And a pyrazole ring, an anthraquinone ring and the like, and particularly preferable are a benzene ring and a naphthalene ring.

Further, the substituent of Z is alkyl,
Examples include groups such as alkoxy, aryl, aryloxy, asil, acyloxy, amino, carbamoyl, nitro, and cyano, and halogen atoms. These imidazoperylene compounds are represented by Bragg in the X-ray diffraction spectrum against Cu-Kα ray. 6.3 ° ± of angle 2θ
0.2 °, 12.5 ° ± 0.2 °, 25.4 ° ± 0.2
°, 27.0 ° ± 0.2 °.

Examples of the compound represented by formula (2) or (3) are shown below.

[0036]

Embedded image

The above compound examples are described in, for example,
Compounds can be synthesized by the methods described in JP-A-128734 and JP-A-59-59686.

The photosensitive layer of the above-mentioned photoreceptor has C
TM, binder resin, antioxidant, electron-accepting substance,
Others can be included.

<< CTM >> Examples of CTM contained in the photosensitive layer of the above-mentioned photoreceptor include carbazole derivatives, oxazole derivatives, thiazole derivatives, oxadiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, and imidazolidine derivatives. , Bisimidazolidine derivatives, styryl compounds, hydrazone compounds, pyrazoline derivatives, oxazolone derivatives, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives, phenazine derivatives, aminostilbene derivatives, triarylamine derivatives, phenylenediamine derivatives, stilbene derivatives, Benzidine derivatives, poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene, and the like. , But it is not limited thereto. These CTMs may be used alone or in combination of two or more.

<< Binder Resin >> As the binder resin used for forming the photosensitive layer of the photosensitive member, any resin can be used. The binder resin is hydrophobic, has a high dielectric constant, and has a high electrical insulating film forming property. It is preferable to use a molecular polymer. Examples of such a polymer include polycarbonate, polyester, methacrylic acid resin, acrylic resin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer,
Vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone-alkyd resin, phenol formaldehyde resin, styrene-alkyd resin, poly-N-vinylcarbazole, polyvinyl butyral, polyvinyl Examples include, but are not limited to, formal. These binder resins can be used alone or as a mixture of two or more.

<< Antioxidant >> In the photosensitive layer of the above photoreceptor,
An antioxidant can be added for the purpose of preventing ozone deterioration. Examples of the antioxidant include hindered phenol, hindered amine, paraphenylenediamine, arylalkane, hydroquinone, spirochroman, spiroidanone and derivatives thereof, and organic sulfur. And organic phosphorus compounds.

Examples of these specific compounds include those described in
Nos. 3-14154, 63-18355, 63-4
No. 4662, No. 63-50848, No. 63-5084
9, No. 63-58455, No. 63-71856,
Nos. 63-71857 and 63-146046. The amount of antioxidant added is CT
The amount is 0.1 to 100 parts by weight, preferably 1 to 50 parts by weight, particularly preferably 5 to 25 parts by weight based on 100 parts by weight of M.

<< Electron-Accepting Substance >> One or two or more known electron-accepting substances are used in the photosensitive layer of the photoreceptor for the purpose of improving sensitivity, increasing residual potential, and reducing fatigue upon repeated use. It can be contained.

The amount of the electron accepting substance added is preferably CGM: electron accepting substance = 100: (0.0
1 to 200), more preferably 100: (0.1 to 10)
0).

The above electron accepting substance may be added to the CTL, and the amount of the electron accepting substance added to such a layer is preferably CTM: electron accepting substance = 100:
(0.01-100), more preferably 100: (0.
1 to 50).

Examples of the electron accepting substance include succinic anhydride, maleic anhydride, dibromomaleic anhydride,
Phthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, 3-nitrophthalic anhydride, 4-nitrophthalic anhydride, pyromellitic anhydride, melitic anhydride,
Tetracyanoethylene, tetracyanoquinodimethane, o
-Dinitrobenzene, m-dinitrobenzene, 1,3,
5-trinitrobenzene, paranitrobenzonitrile,
Picryl chloride, quinone chlorimide, chloranil, bulmanil, dichlorodicyanoparabenzoquinone,
Anthraquinone, dinitroanthraquinone, 2,7-dinitrofluorenone, 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitrofluorenone, 9
-Fluorenylidene [dicyanomethylenemalonodinitrile], polynitro-9-fluorenylidene- [dicyanomethylenemalonodinitrile], picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, 3,5-dinitrobenzoic acid, pentafluorobenzoic acid Examples thereof include acids, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, phthalic acid, melitic acid, and other compounds having a high electron affinity.

The photosensitive layer of the photosensitive member according to the present invention or C
Organic amines can be added to GL for the purpose of improving the charge generation function of CGM, and it is particularly preferable to add a secondary amine.

These compounds are disclosed in JP-A-59-21844.
No. 7, No. 62-8160 and the like.

Further, in the photosensitive layer of the above-mentioned photoreceptor,
If necessary, an ultraviolet absorber or the like may be contained for the purpose of protecting the photosensitive layer, and a dye for correcting color sensitivity may be contained.

<< Solvent or Dispersion Medium for CGL and CTL >> As the solvent or dispersion medium used for forming the above CGL and CTL, butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N, N- Dimethylformamide, acetone, methyl ethyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform,
1,2-dichloroethane, 1,2-dichloropropane,
1,1,2-trichloroethane, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethane,
Examples thereof include dichloromethane, tetrahydrofuran, dioxane, methanol, ethanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, and methyl cellosolve. Further, the CTL can be formed using the same solvent as in the case of CGL.

<Auxiliary Layer> In the above-mentioned photoreceptor of the present invention, if necessary, an auxiliary layer such as a protective layer or an intermediate layer of the photoreceptor may be provided.

The protective layer may contain a thermoplastic resin in an amount of less than 50% by weight, if necessary, for the purpose of improving workability and physical properties (prevention of cracking, imparting flexibility, etc.). The intermediate layer functions as an adhesive layer or a blocking layer between the substrate and the photosensitive layer. In addition to the binder resin, for example, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, and vinyl chloride
-Vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, casein, N-alkoxymethylated nylon, starch and the like are used.

[Image Forming Method and Apparatus Thereof] The image forming method of the present invention employs a photoreceptor having the above-described structure, preferably, as shown in FIG.
Alternatively, the charging, image exposure, development, transfer, fixing, and cleaning are performed using a photoreceptor shown in FIG. 2C and using a digital copying machine or a printer or a digital copying machine-printer as an image forming apparatus. And an image forming process including static elimination of the photoreceptor surface before charging by static elimination light,
Image formation is performed repeatedly over a long period of time.

FIG. 3 shows an example of an image forming apparatus which can be used in the present invention. In FIG. 3, reference numeral 20 denotes a roughened surface having a surface roughness Rz of 0.5 to 3 μm by an intense laser beam. A drum-shaped photoconductor containing a Y-type titanyl phthalocyanine compound or imidazoperylene compound as CGM, 21 as a CGM, 21 as a charger, 22 as a CGM, can be modulated by an image signal from a scanner or an external communication means. L is an image exposure, 23 is a contact developing device (or a non-contact developing device), 24 is a DC bias power source (or an AC bias power source on which a DC bias is superimposed), 25
Is a feed roller, 26 is a timing roller, 27
Is a transfer device, 28 is a separator, 29 is a heat roller fixing device, 3
0 is a cleaning device, 31 is a cleaning blade,
Reference numeral 32 denotes a pre-charging charge removing light. The external communication means include, for example, a computer, a facsimile, a system device, and the like. As the coherent monochromatic light device,
For example, a solid laser device such as a ruby laser or a semiconductor laser, or a gas laser device such as a He-Ne laser or a carbon dioxide laser may be used.
A laser device having an emission wavelength range of 0 nm is used.

In FIG. 3, the photoreceptor 20 has a coherent monochromatic light device (hereinafter referred to as a coherent monochromatic light device) which is charged by a charger 21 and then modulated by an image signal 22 from a scanner or external communication means. A dot-shaped electrostatic latent image is formed by image exposure L from a laser device. The electrostatic latent image is developed by, for example, a contact-type (or non-contact-type) developing unit 23 to form a toner image.
Is transferred and separated on the transfer paper P conveyed in synchronization with the photoreceptor by the operation of the transfer device 27 and the separation device 28, and the fixing device 29
A fixed image is obtained by the action of

As described above, in the image forming method of the present invention, a copying machine having a scanner, a printer for forming an image by an external image signal, an image forming apparatus having both functions of the copying machine and the printer, and the like are used. You may.

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto.

[0058]

EXAMPLE 1 <Production of Photoconductor 1 (Drum Shape)> Using the surface roughening apparatus shown in FIG. 1, the energy oscillated from the apparatus was 6 × 10 ^7.
The surface roughness Rz is 1. with a laser beam of W / cm ² .
80 mm in diameter and 360 m in length, roughened to 5 μm
m, a polyamide undercoat layer on an aluminum cylindrical substrate having a thickness of 1.25 mm, and a compound G having the following structure as CGM:
CGL (film thickness: 0.5 μm) using -1 and CTL (film thickness: 25 μm) using compound T-1 having the following structure as CTM were provided in this order to obtain photosensitive drum 1.

[0059]

Embedded image

The photoreceptor 1 is a digital exposure type electrophotographic copier Konica 7060 (A4, 60 sheets per minute, a light source for image exposure is a semiconductor laser with an emission wavelength of 780 nm), and the photoreceptor is -750 (V). Charge, and DC-
The image was developed by a reversal development method using a negatively chargeable two-component developer under a bias of 600 (V).

The above-described copying machine is used to repeat charging and exposing 100,000 times, and the unexposed portion potential VH (V) and exposed portion potential VL (V) are measured at the initial stage and after 100,000 repetitions. The results are shown in Table 1. Using the above copying machine, image formation was repeated 100,000 times, and the images were observed. The images were evaluated according to the following evaluation criteria according to the “O” and “X” methods. The results are shown in Table 1.

<Evaluation Criteria> A moire did not occur at all.

○ Moire hardly occurred.

(4) Moire is generated, but there is no practical problem.

X: Many moirés occurred.

Examples 2 and 3 <Preparation of Photoconductors 2 and 3 (Drum Shape)> Degree of Roughening of Substrate
Photoconductors 2 and 3 were obtained in the same manner as in Example 1, except that z was changed to 0.6 and 2.9.

Except that the photosensitive members 2 and 3 were used, charging exposure was repeated 100,000 times using the copying machine as in Example 1, and the initial and after 100,000 times repetition of charging exposure were performed. The exposed portion potential VH (V) and the exposed portion potential VL (V) were measured, and the results are shown in Table 1. Using the above copying machine, image formation was repeated 100,000 times, and moire based on the interference fringes of the 100,000th image was observed. The results are shown in Table 1.

Examples 4 and 5 <Preparation of Photoconductors 4 and 5 (Drum Shape)> The photosensitive materials of Example 1 were changed except that CGM was changed to Compound Example 1 (G-2) and Compound Example 15 (G-3). Photoconductors 4 and 5 were obtained in the same manner as for photoconductor 1. When the CGM was changed, the light amount of the laser beam was adjusted.

The above copier was used in the same manner as in Example 1 except that the photoconductors 4 and 5 were used and a semiconductor laser having an emission wavelength of 680 nm was used as a light source for image exposure instead of the semiconductor laser having an emission wavelength of 780 nm. Table 1 shows the unexposed portion potential VH (V) and the exposed portion potential VL (V) obtained by repeating the charging exposure for 100,000 times by the above-mentioned method.
Further, the moiré of the image obtained by repeating the image formation 100,000 times by using the above-mentioned copying machine was evaluated by the above-mentioned evaluation criterion according to the “O” and “X” method, and the results are shown in Table 1.

Embodiment 6 <Preparation of Photoconductor 6 (Drum Shape)>
Photoreceptor 6 was obtained in the same manner as in Photoreceptor 1 of Example 1, except for changing to -4.

[0071]

Embedded image

Except for using the photoreceptor 6, the unexposed portion potential VH (V) and the exposed portion potential obtained by repeating the charge exposure for 100,000 times by the copying machine in the same manner as in Example 1 VL (V) is shown in Table 1. Further, the moiré of the image obtained by repeating the image formation 100,000 times using the above copying machine was evaluated as “「 ”,“ X ”according to the evaluation criteria.
The method and evaluation were performed, and the results are shown in Table 1.

Comparative Examples 1 and 2 Photoconductors 7 and 8 were obtained in the same manner as photoconductor 1 of Example 1 except that the surface roughness Rz of the substrate was changed to 0.2 and 3.1.

The unexposed portion potential VH (V) obtained by repeating the charging exposure by 100,000 times by the copying machine in the same manner as in the first embodiment except that the photosensitive members 7 and 8 are used.
Table 1 shows the exposure portion potential VL (V). Further, using the above copying machine, the moiré of an image obtained by repeating image formation 100,000 times was evaluated as “「 ”,
The evaluation was performed according to the “x” method, and the results are shown in Table 1.

[0075]

[Table 1]

As is clear from Table 1, in Examples 1 to 6, clear images were obtained without occurrence of moire due to interference fringes during the repeated image formation process, and the CGM is preferably Y-type titanyl phthalocyanine or imidazo. In Examples 1 to 4 using the photoconductors 1 to 4 containing perylene, the rise in the exposure portion potential VL (V) due to the decrease in the sensitivity of the photoconductor is small, and thus the image density during image formation is small and the quality is low. However, it can be seen that moiré was large in Comparative Examples 1 and 2, and that cleaning was poor in Comparative Example 2 and the practicality was poor.

[0077]

As demonstrated by the examples, according to the photoreceptor, the image forming method and the image forming apparatus of the present invention, an organic photosensitive layer is formed on a substrate, particularly Y-type titanyl phthalocyanine or imidazoperylene as a charge generating substance. When an image is formed by irradiating a laser beam modulated by image information to an organic photoreceptor obtained by providing an organic photosensitive layer using, no moiré or cleaning failure based on interference fringes of the laser beam is generated, and good. Excellent effects can be obtained, such as stable images being obtained stably.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a roughening apparatus.

FIG. 2 is a diagram illustrating a layer configuration of a photoreceptor.

FIG. 3 is a diagram illustrating an example of an image forming apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Processed part 2 Drum-shaped base 3 Chuck device 4 Rotation axis 5 Drive source 6 Laser processing part 7 Guide rail 8 Laser oscillation part 9 Light guide tube 10a Scanner 10b Laser beam emission part 11 Conductive base 12 CGL 13 CTL 14 Photosensitivity Layer 15 Intermediate layer 16 Layer containing CTM as a main component 17 CGM 20 Photoconductor 21 Charger 22 Coherent monochromatic light device modulated by image signal from scanner or external communication means L Image exposure 23 Contact developer (or Non-contact developing device) 24 DC bias power supply (or AC bias power supply on which DC bias is superimposed) 25 Feeding roller 26 Timing roller 27 Transfer device 28 Separator 29 Heat roller fixing device 30 Cleaning device 31 Cleaning blade 32 Static electricity removal light P Transfer paper

Claims (6)

[Claims] 1. Surface roughness Rz by irradiating a laser beam
An electrophotographic photoreceptor for coherent light, comprising a substrate having a surface roughness of 0.5 to 3 μm. 2. The electrophotographic photoreceptor for coherent light according to claim 1, further comprising a photosensitive layer using Y-type titanyl phthalocyanine or imidazoperylene as a charge generating substance. 3. Irradiation of a laser beam to surface roughness Rz
Using an electrophotographic photoreceptor for coherent light having a substrate roughened to 0.5 to 3 μm. 4. The image forming method according to claim 3, wherein an electrophotographic photoreceptor for coherent light having a photosensitive layer using Y-type titanyl phthalocyanine or imidazoperylene as a charge generating substance is used. 5. Irradiation of a laser beam to surface roughness Rz
An image forming apparatus using an electrophotographic photoreceptor for coherent light having a substrate roughened to 0.5 to 3 μm. 6. The image forming apparatus according to claim 5, wherein an electrophotographic photoreceptor for coherent light having a photosensitive layer using Y-type titanyl phthalocyanine or imidazoperylene as a charge generating substance is used.