JPH08314175A - Image forming method, image forming device and image forming unit - Google Patents

Abstract

PURPOSE: To provide an image forming method which has high sensitivity, which does not have image quality lowering, in which the deterioration of sensitivity is reduced, and whose image stability is excellent by including inorganic particulates in the outermost surface layer of a photoreceptor and performing cleaning to remove residual toner by means of a rubber blade and a brush-state cleaning member. CONSTITUTION: As to this image forming method by which a toner image formed by developing an electrostatic latent image formed on a photoreceptor 10 by performing electrification and image exposure by developer is transferred on a transferring body, then process for cleaning the photoreceptor 10 is repeated; the inorganic particulates are included in the outermost surface layer of the photoreceptor 10, and the residual toner is removed by cleaning by the rubber blade 221 and the brush 222 state cleaning member 22. At least the outermost surface layer of the photoreceptor 10 in which a charge generating layer and a charge transferring layer are laminated, in which a charge generating material is mixed with a charge transferring material, or on the surface of which a protecting layer is further provided includes particulates.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method for visualizing an electrostatic latent image in electrophotography with a developer.

More specifically, in an electrophotographic process, an image forming apparatus and an image forming apparatus which perform cleaning by using a photoreceptor such as an organic photoreceptor (OPC) and performing a strong pressure contact with the photoreceptor such as a blade cleaning method. The present invention relates to an image forming method using a photoconductor in which inorganic fine particles are contained in the outermost surface layer in a unit.

[0003]

2. Description of the Related Art Conventionally, in an image forming apparatus using the electrophotographic method of the Carlson method, after uniformly charging the surface of the photoconductor, the charge is erased imagewise by exposure to form an electrostatic latent image, The electrostatic latent image is developed with toner, and then the toner is transferred and fixed on paper or the like.

On the other hand, the photoreceptor is subjected to removal of adhered toner, charge removal, and surface cleaning, and is repeatedly used for a long period of time.

Therefore, the electrophotographic photosensitive member has not only electrophotographic characteristics such as good charging characteristics and good sensitivity but also small dark decay, but also printing durability, abrasion resistance, moisture resistance, etc. in repeated use. It is also required to have good physical properties and resistance (environmental resistance) to ozone generated during corona discharge and ultraviolet rays during exposure.

Conventionally, selenium has been used as an electrophotographic photoreceptor.
Inorganic photoconductors having an inorganic photoconductive substance such as zinc oxide and cadmium sulfide as a main component of a photosensitive layer have been widely used. However, in recent years, as a photosensitive layer of an electrophotographic photoreceptor, a carrier generating function and a carrier transporting function are shared by different substances, and a substance exhibiting each function is selected from a wide range in accordance with desired characteristics to have high sensitivity and durability. There is a tendency to put into practical use organic photoconductors with large numbers.

[0007]

Such a function-separated type organic photoreceptor is conventionally mainly used for negative charging,
As described in JP-A-60-247647, a structure is provided in which a thin carrier generation layer is provided on a support and a relatively thick carrier transport layer is provided thereon. However, since this carrier transporting layer is composed of a polymer binder, a carrier transporting substance, etc., it is gradually abraded by abrasion of the developer spikes on the developing sleeve, transfer paper, a cleaning member, etc. during use, and the initial transport There is a problem that the charging characteristic and the light attenuation characteristic cannot be obtained.

In view of these problems, a polycarbonate resin is preferably used as the binder resin of the charge transport layer, which is the outermost surface layer of the photoreceptor, from the viewpoint of electrophotographic characteristics, mechanical strength and the like. . However, as compared with the inorganic photoconductor, the scratch resistance and the abrasion resistance are inferior and the sufficient performance is not obtained at present.

In order to solve such a problem, introduction of a substituent having fluorine on the carbon between phenylene rings (Japanese Patent Laid-Open No. 63-6).
No. 5444), substitution of an alkyl group or a halogen atom on the phenylene ring (JP-A-62-148263), or a copolymer of monomers in which both phenylene rings are substituted with a phenyl group or a cyclohexyl group (JP-A No. 269942
No. 1,269,943) and the like have been proposed, but they do not have sufficient surface strength, are vulnerable to abrasion and scratches, deteriorate image quality during repeated use, and reduce sensitivity due to reduction in film thickness due to abrasion. I have a problem.

Further, it has been proposed that the outermost surface layer contains organic fine particles and inorganic fine particles so that the surface has strength. However, since the fine particles are present on the surface and a non-uniform structure is formed, residual toner is removed. It is known that problems such as slipping through occur in the cleaning process.

On the other hand, as a method for cleaning the transfer residual toner on the photosensitive member, cleaning with a blade made of polyurethane or the like is often adopted because of its good cleaning property.

The physical properties of the cleaning blade and the contact load on the photoconductor have a great influence on the cleaning property of the transfer residual toner and the wear and scratches of the photoconductor. Considering physical properties such as elasticity and coefficient of friction, select blades with suitable physical properties,
It is necessary to set an appropriate contact weight. However,
In many cases, the cleaning property and the wear of the photoconductor become defective due to fluctuations in the surrounding temperature and humidity environment, and it is the current situation that trial and error must be repeated in selecting the cleaning blade and setting the weight.

The present invention has been made to solve the above problems. That is, an image forming method, an image forming apparatus, and an image forming apparatus which are highly sensitive and have less wear of a photosensitive layer of an electrophotographic photosensitive member, and which have less image quality deterioration and sensitivity deterioration and an image stability using a cleaning device suitable for the same are provided. It is intended to provide an image forming unit.

[0014]

The object of the present invention is achieved by adopting the following constitution.

(1) A step of developing an electrostatic latent image formed by charging and image exposure on a photosensitive member with a developer, transferring the formed toner image onto the transfer member, and then cleaning the photosensitive member. The image forming method is characterized in that inorganic fine particles are contained in the outermost surface layer of the photoconductor and residual toner is removed by cleaning with a rubber blade and a brush-like cleaning member.

(2) The particle size of the inorganic fine particles is 0.05.
The image forming method as described in (1) above, wherein

(3) The image forming method according to (1) or (2), wherein the inorganic fine particles are subjected to a hydrophobic treatment.

(4) The image forming method described in (1), (2) or (3), wherein the inorganic fine particles are silica.

(5) In an image forming apparatus having a charging device, an image exposing device, a developing device, a transfer separator and a cleaning device around a photoconductor formed on a conductive support, inorganic fine particles are added to the photoconductor. In the image forming apparatus, the residual toner contained in the outermost surface layer is cleaned and removed by the cleaning device with a rubber blade and a brush-shaped cleaning member.

(6) The particle size of the inorganic fine particles is 0.05.
The image forming apparatus according to (5), wherein the image forming apparatus has a thickness of 2 μm.

(7) The image forming apparatus according to (5) or (6), wherein the inorganic fine particles are subjected to a hydrophobic treatment.

(8) The image forming apparatus as described in (5), (6) or (7), wherein the inorganic fine particles are silica.

(9) An image forming apparatus having a charging device, an image exposing device, a developing device, a transfer separator, and a cleaning device around a photosensitive member formed on a conductive support, wherein the inorganic fine particles are The residual toner contained in the outermost surface layer of the photoconductor is cleaned and removed by the cleaning device with a rubber blade and a brush-shaped cleaning member, and the photoconductor, the charging device, the image exposure device, the developing device, the transfer separator, and An image forming unit, wherein at least one of the cleaning devices is integrally configured as an image forming unit.

(10) The particle size of the inorganic fine particles is 0.0
The image forming unit according to (9), which has a thickness of 5 to 2 μm.

(11) The image forming unit according to (9) or (10), wherein the inorganic fine particles are subjected to a hydrophobic treatment.

(12) The image forming unit described in (9), (10) or (11), characterized in that the inorganic fine particles are silica.

Further, just before the cleaning step, a charge removing step or the like may be provided to facilitate cleaning of the developer if necessary.

Next, an outline of the electrophotographic photosensitive member of the present invention will be described, but this is a representative example and the present invention is not limited thereto.

The photoconductor of the present invention is a photoconductor having a charge generation layer, a charge transport layer laminated thereon, a photoconductor having a photoconductor layer having a mixture of a charge generation substance and a charge transport substance formed thereon, or a photoconductor formed on these photoconductors. It is a photoreceptor in which fine particles are contained in at least the outermost surface layer of the photoreceptor having a protective layer. Further, an undercoat layer may be provided between the conductive substrate and the photosensitive layer, if necessary.

As the conductive substrate, a metal plate made of aluminum, stainless steel, iron or the like, or a metal layer made of aluminum, palladium, gold or the like is provided on the surface of a flexible support such as paper or plastic film by laminating or vapor deposition. It is possible to use a material having a layer containing a conductive compound such as a conductive polymer, indium oxide or tin oxide applied or vapor-deposited on the surface of a flexible support such as paper or plastic film.

The subbing layer used as required includes casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, polyvinyl butyral, phenol resin, polyamides (nylon 6, nylon 66, alkoxymethylated). Nylon etc.), polyurethane, gelatin and aluminum oxide are used. The thickness of the undercoat layer is preferably 0.1 to 10 μm, and particularly preferably 0.1 to 5 μm.

The charge generating layer is a layer containing a charge generating substance, and the charge generating substance is not particularly limited, and examples thereof include a phthalocyanine pigment, a polycyclic quinone pigment, an azo pigment, a perylene pigment, and an indigo pigment. Pigments, quinacridone pigments, azurenium pigments, squarylium dyes, cyanine dyes, pyrylium dyes, thiopyrylium dyes, triphenylmethane dyes, styryl dyes and the like can be used, and these are formed alone or dispersed in a resin.

As the resin used here, styrene-acrylic resin, polycarbonate resin, polyester resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, styrene resin, polyvinyl acetate,
Styrene-butadiene resin, vinylidene chloride-acrylonitrile resin, vinyl chloride-vinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone alkyd resin, phenol formaldehyde resin, polyvinyl acetal resin, polyvinyl butyral resin, etc. be able to.

The charge-transporting layer is a layer containing a charge-transporting substance, and the charge-transporting substance is not particularly limited, and examples thereof include an oxazole derivative, an oxadiazole derivative, a thiazole derivative, a thiadiazole derivative and a triazole derivative. , Imidazole derivative, imidazolone derivative, imidazoline derivative, bisimidazolidine derivative, styryl compound, hydrazone compound, benzidine compound, pyrazoline derivative, stilbene compound, amine derivative, oxazolone derivative, benzothiazole derivative, benzimidazole derivative, quinazoline derivative , Benzofuran derivative, acridine derivative, phenazine derivative, aminostilbene derivative, poly-N-vinylcarbazoles, poly-1-vinylpyrenes, poly-9-vinylant Mosses and the like. It is formed by dispersing or dissolving these in a resin alone or in combination.

As the resin used here, styrene-acrylic resin, polycarbonate resin, polyester resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, styrene resin, polyvinyl acetate,
Styrene-butadiene resin, vinylidene chloride-acrylonitrile resin, vinyl chloride-vinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone alkyd resin, phenol formaldehyde resin, polyvinyl acetal resin, polyvinyl butyral resin, etc. be able to. The thickness of the charge transport layer is 5 to 50 μm, preferably 10 to 40
μm.

In the case of a photosensitive layer composed of a mixture of a charge transport substance and a charge generating substance, the above charge transport substance and the charge generating substance are appropriately mixed and dispersed in the resin shown above. It is obtained by forming a layer later. in this case,
The layer thickness is from 5 to 50 μm, preferably from 10 to 40 μm.

The inorganic fine particles used in the layer containing the fine particles of the present invention are not particularly limited, but those having a Mohs hardness of 5 or more are preferable. Specifically, oxides such as titanium oxide, silica, zirconium oxide and alumina, carbon nitride, aluminum nitride, nitrides such as silicon nitride, carbides such as silicon carbide, strontium titanate and titanate compounds such as barium titanate. And so on. Of these, silica is particularly preferable.

The Mohs hardness of the inorganic fine particles indicates the Mohs hardness of the substance having the material. The Mohs hardness is a relative hardness evaluated by the presence or absence of scratches using a standard substance in which talc is 1 and diamond is 10 in sequence.

These fine particles have a number average primary particle diameter of 0.
It is preferably from 0.1 to 5 μm. More preferably 0.
It is 05-2 micrometers. When the particle size is large, the surface layer itself becomes brittle, the desired improvement in durability cannot be exhibited, and the presence of fine particles causes damage to the cleaning mechanism. If the particle size is small,
The presence of fine particles does not improve the hardness, and the durability does not improve.

Further, when the inorganic fine particles are hygroscopic, it is preferable that they are hydrophobic because the electric resistance of the surface of the photosensitive member may be lowered in a high humidity environment to cause image defects such as image blurring. In the case of hydrophilic inorganic fine particles, it is preferable to perform hydrophobic treatment by a known method. As a method for hydrophobizing, for example, a well-known hydrophobizing agent such as a titanium coupling agent, a silane coupling agent, a polymeric fatty acid or a metal salt thereof can be used for treatment.

Examples of the titanium coupling agent include tetrabutyl titanate, tetraoctyl titanate, isopropyl isostearoyl titanate, isopropyl tridecylbenzene sulfonyl titanate and bis (dioctyl pyrophosphate) oxyacetate titanate.

Further, as the silane coupling agent, γ
-(2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N-β- (N-vinylbenzylaminoethyl) γ- Aminopropyltrimethoxysilane hydrochloride,
Hexamethyldisilazane, methyltrimethoxysilane,
Butyltrimethoxysilane, isobutyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, phenyltrimethoxysilane, o-methylphenyltrimethoxysilane, p-methylphenyltrimethoxysilane Etc.

The fatty acids and their metal salts include undecyl acid, lauric acid, tondecanoic acid, myristic acid, palmitic acid, pentadecanoic acid, stearic acid, heptadecanoic acid, arachidic acid, montanic acid, oleic acid,
Examples include long-chain fatty acids such as linoleic acid and arachidonic acid.
Examples of the metal salt include salts with metals such as zinc, iron, magnesium, aluminum, calcium, sodium and lithium.

These compounds are preferably added in an amount of 1 to 10% by weight with respect to the above-mentioned inorganic fine particles for coating, preferably 3 to 7% by weight. Further, these materials can be used in combination, and they are usually formed as a monomolecular layer or a layer close thereto on the surface of the inorganic fine particles.

Furthermore, the volume resistance of these fine particles themselves is 1
0 ⁸ or more Ωcm is preferable. If this resistance is lower than this range, the resistance of the surface is lowered, the charge retaining function is lowered, and the problem of causing image defects is induced.

When the surface layer is formed, it can be formed by dispersing the fine particles in a resin and coating the resin. The constituent resin is not particularly limited, and examples thereof include styrene-acrylic resin, polycarbonate resin, polyester resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, styrene resin, polyvinyl acetate, and styrene-butadiene resin. , Vinylidene chloride-acrylonitrile resin, vinyl chloride-vinyl acetate resin, vinyl chloride-vinyl acetate-maleic anhydride resin, silicone resin, silicone alkyd resin, phenol formaldehyde resin, polyvinyl acetal resin, polyvinyl butyral resin, and the like.

The content of fine particles in these resins is 1 to 200 parts, preferably 5 to 10 parts, relative to 100 parts of the resin.
It is 0. If the amount is less than 1 part, the amount of the fine particles is too small to exert the effect of improving the hardness. If the amount is more than 200 parts, the hardness is improved. Scattering occurs, which causes image defects.

Further, the surface layer of the present invention has a thickness of 0.2 to 10 μm.
m, preferably 0.4 to 5 μm. When this layer is thin, the effect of improving durability of the present invention is not exerted, and
When the film thickness is large, the effect of improving durability is exhibited, but image defects due to light scattering and a problem of sensitivity decrease occur.

The layer containing the fine particles of the present invention preferably contains a charge transporting substance. That is, since the specific surface layer is not formed by containing the charge transport substance, the charge is uniformly transported, and the charge distribution according to the image can be stably formed. The content ratio of this charge transport substance in the surface layer is
30 to 300 with respect to 100 parts of the resin forming the protective layer
Parts, preferably 50 to 200 parts.

FIG. 1 shows a schematic sectional view of an apparatus according to the image forming method of the present invention.

In FIG. 1, reference numeral 10 denotes a photosensitive drum which is an image bearing member, which is formed by coating an organic photosensitive member on the drum and is grounded and driven and rotated clockwise. 12 is a charger,
The peripheral surface of the photosensitive drum 10 is uniformly charged by corona discharge. Prior to the charging by the charger 12, it is preferable that the peripheral surface of the photoconductor is discharged by exposure by the PCL 11 using a light emitting diode or the like in order to eliminate the history of the photoconductor until the previous printing.

After uniformly charging the photosensitive member, the image exposure device 13 performs image exposure based on the image signal. The image exposure device 13 in this figure is one in which the optical path is bent by the reflection mirror 132 through a polygon mirror 131, an f.theta. An electrostatic latent image is formed by scanning. The image exposure means is appropriately selected depending on the purpose, such as slit exposure, laser exposure, or LED exposure.

The electrostatic latent image is then developed by the developing device 14. At the periphery of the photoconductor drum 10, a developing device 14 in which a developer including toner such as yellow (Y), magenta (M), cyan (C), and black (K) and a carrier is incorporated, respectively.
First, the development of the first color is carried out by the developing sleeve 141 which contains a magnet and holds the developer and rotates. The developer is a carrier in which a ferrite core is coated with an insulating resin around it, a polyester as a main material, a pigment according to the color, and a charge control agent,
The toner is composed of toner to which silica, titanium oxide, etc. are added, and the developer is regulated to a layer thickness of 100 to 600 μm on the developing sleeve 141 by the layer forming means and conveyed to the developing area, where it is developed with the photosensitive drum 10. Development is performed by applying a DC or AC bias potential between the sleeves 141.

In the full-color image formation, after the visualization of the first color is completed, the second color image formation process is performed, and the scorotron charger 12 performs uniform charging again.
A latent image based on the image data of the color is formed by the image exposure device 13. An image forming process similar to that for the second color is performed for the third and fourth colors, and a visible image of four colors is formed on the peripheral surface of the photosensitive drum 10.

On the other hand, in the monochrome electrophotographic apparatus, the developing device 1
No. 4 is composed of one kind of black toner, and an image can be formed by one development.

The recording paper P is temporarily stopped, and when the transfer timing is adjusted, it is fed to the transfer area by the rotation operation of the paper feed roller 17.

In the transfer area, the transfer device 18 is pressed against the peripheral surface of the photosensitive drum 10 in synchronization with the transfer timing.
The supplied recording paper P is sandwiched and the multicolor image is transferred at once.

Next, the recording paper P is discharged at almost the same time by the separator 19 which is brought into a pressure contact state, separated from the peripheral surface of the photosensitive drum 10 and conveyed to the fixing device 20, and the heat roller 201.
The toner is fused by heating and pressurizing the pressure roller 202, and then the toner is discharged to the outside of the apparatus through the paper discharge roller 21. The transfer device 18 and the separator 19 are retreated and separated from the peripheral surface of the photoconductor drum 10 after the recording paper P has passed to prepare for the next toner image.

On the other hand, the photosensitive drum 10 from which the recording paper P is separated
The residual toner is removed and cleaned by the rotation of the brush 222 of the cleaning device 22 and the pressure contact of the rubber blade 221, and the process of the next image formation is performed by receiving the charge removal by the PCL 11 and the charging by the charging device 12 again. When a color image is superimposed on the photoconductor, the brush 2 is used.
The rubber blade 221 and the rubber blade 221 move immediately after cleaning the surface of the photoconductor and retract from the peripheral surface of the photoconductor drum 10.

Reference numeral 30 designates a photosensitive drum, a charger, a transfer device,
A cartridge as a detachable image forming unit in which a separator and a cleaning device are integrated.

As the uniform charger 12 of the photosensitive drum 10, a corona charging device is generally widely used. Further, a transfer roller and a corona transfer means are generally widely used for the transfer device. As an electrophotographic image forming apparatus,
Of the above-mentioned components such as the photoconductor drum, the charger, the image exposure device, the developing device, the transfer device, the separator, and the cleaning device, a plurality of components are integrally combined to form an image forming unit. The unit may be detachably attached to the apparatus body. For example, at least one of a charging device, a developing device, and a cleaning device is integrally supported together with a photoconductor to form an image forming unit, which is a detachable single unit in the main body of the apparatus, and a guide means such as a rail of the main body of the apparatus is used. It may be detachable. At this time, the apparatus main body may be configured with a charging unit and / or a developing unit.

When the electrophotographic apparatus is used as a copying machine or a printer, the image exposure device irradiates the photoconductor with reflected light or transmitted light from the original, or reads the original with a sensor and converts it into a signal. It is performed by scanning a laser beam, driving an LED array, driving a liquid crystal shutter array, and irradiating light on a photoconductor in accordance with a signal.

When used as a printer for a facsimile, the image exposure device 13 serves as an exposure for printing the received data.

FIG. 2 shows an example of a cleaning device using a rubber blade and a brush.

In FIG. 2, reference numeral 10 denotes a photosensitive drum, which is rotating in the direction indicated by the arrow in the figure. As described above, the electrostatic latent image is formed on the surface of the photoconductor drum 10, the latent image is visualized by the toner, and the visualized image is transferred to the recording paper. In order to remove the toner T remaining on the photosensitive drum 10 after the transfer,
A cleaning device 22 is provided.

The cleaning device 22 shown in FIG. 2 brushes the surface of the photoconductor drum 10 so as to scrape off the toner T on the photoconductor drum 10, a rubber blade 221 as a cleaning blade, the brush 222 and the brush 222. A collecting member 223 for collecting the toner T separated from the photosensitive drum 10 by the rubber blade 221 is provided. Generally, the collecting member 223 is arranged so as to contact the surface of the photoconductor drum 10 to prevent the toner T scraped by the rubber blade 221 from scattering outside the cleaning device 22.

The rubber blade 221 is preferably an elastic rubber blade made of polyurethane rubber, and the contact angle θ with the photosensitive drum 10 is preferably an acute angle as shown in FIG.

The brush 222 is forcibly driven to rotate in order to make a speed difference with the photosensitive drum 10. The direction of rotation may be either forward or reverse with respect to the photoconductor drum 10. When it is rotated in the forward direction, it is preferably driven at a speed 1.3 times or more that of the photoconductor. If the speed difference is less than this, the scraping effect becomes insufficient. The material is polypropylene, acrylic, nylon, etc.
Carbon black or the like may be dispersed in order to give conductivity. By giving conductivity, it is possible to electrically neutralize the toner and external additives of the toner and facilitate scraping of the toner with a brush or a rubber blade.

The conductivity is preferably about 10 ⁸ Ω · cm or less. If the electric resistance is higher than this, a sufficient neutralizing effect cannot be obtained. Further, in order to maximize the effect of physically scraping the toner from the photoconductor, it is necessary to adjust the thickness, length, density, etc. of the bristles. The thickness is preferably 10 to 100 μm in terms of hair diameter. If the thickness is smaller than this, the scraping effect cannot be obtained, and if the thickness is larger than this, the hair is too stiff and the photoreceptor is adversely affected by abrasion and scratches. The length is preferably 1 to 10 mm. If the length is shorter than this, the hair is too stiff to give adverse effects such as abrasion and scratches to the photoconductor, and if the length is longer than this, the scraping effect cannot be obtained.

The density is 1,000 to 100,000 pieces /
cm ² is preferred. If the density is lower than this, the scraping effect cannot be obtained, and if the density is higher than this, the toner is clogged, and cleaning failure such as toner filming occurs.

In the present invention, by containing the inorganic fine particles in the outermost surface layer, the electrophotographic properties such as charge retention, sensitivity and residual potential are excellent, and the film thickness wear is small even when repeatedly used, and the rubber blade is used. Also, since a cleaning failure is not caused by contacting and cleaning the brush, stable image quality can be obtained.

[0072]

【Example】

(1) Preparation of Photoreceptor Photoreceptor Polyamide resin CM-8000 (Toray Industries, Inc.) (30 g) was put into a mixed solvent of methanol (900 ml) and 1-butanol (100 ml), and heated and dissolved at 50 ° C. After cooling to room temperature, using this liquid, the outer diameter was 80 mm and the length was 355.5.
An intermediate layer having a thickness of 0.5 μm was formed by dip coating on a mm aluminum drum.

Next, 5 g of polyvinyl butyral resin S-REC BX-1 (Sekisui Chemical Co., Ltd.) was added to MEK1000.
It was dissolved in ml, 10 g of Exemplified Compound G "Chemical Formula 1" was mixed, and the mixture was dispersed for 20 hours using a sand mill.
Using this solution, a charge generation layer having a thickness of 0.5 μm was formed by dip coating on the intermediate layer.

Thereafter, 100 g of Exemplified Compound T "Chemical Formula 1" and BPZ type polycarbonate resin Panlite TS-205 were used.
0 (Teijin Kasei) 150 g dichloromethane 100
Dissolved in 0 ml. Using this solution, a charge transport layer having a thickness of 20 μm was formed on the charge generation layer by dip coating.

Thereafter, 20 g of Exemplified Compound T "Chemical Formula 1" and B
PZ type polycarbonate resin Panlite TS-2050
(Teijin Kasei) 30 g dichloromethane 1000 m
10 g of 0.2 μm silica fine particles in a solution dissolved in
It was added and dispersed in an ultrasonic bath for 20 minutes. Using this solution, a ring-coated surface protection layer having a thickness of 3 μm was formed on the charge transport layer.

Finally, it was heated and dried at 100 ° C. for 1 hour to prepare a photoreceptor in which an intermediate layer, a charge generation layer, a charge transport layer and a surface protective layer were sequentially laminated.

[0077]

Embedded image

Photoreceptor A photoreceptor was prepared in the same manner as the photoreceptor 1 except that the silica fine particles of 0.2 μm were changed to the silica fine particles of 0.03 μm.

Photoreceptor A photoreceptor was prepared in the same manner as the photoreceptor 1 except that the 0.2 μm silica fine particles were changed to 2.0 μm silica fine particles.

Photoconductor A photoconductor was prepared in the same manner as the photoconductor 1 except that the silica fine particles of 0.2 μm were changed to the silica fine particles of 2.5 μm.

Photoreceptor A photoreceptor was prepared in the same manner as the photoreceptor 1 except that 0.2 μm silica fine particles were changed to 0.2 μm zirconium fine particles.

Photoreceptor A photoreceptor was prepared in the same manner as the photoreceptor 1 except that the 0.2 μm silica fine particles were changed to 0.1 μm silica fine particles.

Photoreceptor A photoreceptor was prepared in the same manner as the photoreceptor 1, except that the silica fine particles of 0.2 μm were changed to the titanium oxide fine particles of 0.5 μm.

Photoreceptor A photoreceptor was prepared in the same manner as the photoreceptor 1 except that the silica fine particles of 0.2 μm were changed to the alumina fine particles of 0.5 μm.

Photoreceptor A photoreceptor was prepared in the same manner as the photoreceptor 1 except that fine particles were not added.

(2) Evaluation The photoconductors 1 to 5 were mounted on U-Bix 4155 manufactured by Konica Co., Ltd., and a 100,000-copy actual copying test was conducted under different conditions as shown in the table below.

The evaluation was carried out based on the presence or absence of image defects during actual copying, the amount of change in the surface potential of the photosensitive member before and after the actual copying test, and the amount of film thickness loss. Here, Vb and Vw are potentials corresponding to the black image portion (reflection density 1.30) and the white image portion (reflection density 0.00) of the original, respectively. In all experiments, the brush was driven in the forward direction at 1.4 times the speed of the photoconductor.

[0088]

[Table 1]

As shown in the table above, in the image forming method of the present invention,
It can be seen that even when repeatedly used, the film thickness of the photoconductor is less likely to be worn, and a stable image can be obtained without causing cleaning failure.

[0090]

According to the present invention, the amount of change in the surface potential of the photoreceptor is small even after repeated use, and the electrophotographic characteristics are excellent.
In addition, it is possible to provide an image forming method, an image forming apparatus, and an image forming unit that can obtain stable image quality because the film thickness is less worn even when repeatedly used and a cleaning failure does not occur.

[Brief description of drawings]

FIG. 1 is a sectional view of an image forming apparatus according to the present invention.

FIG. 2 is a sectional view of an essential part of an image forming apparatus according to the present invention.

FIG. 3 is a sectional view of a cleaning blade according to the present invention.

[Explanation of reference numerals] 10 photoconductor drum 22 cleaning device 221 rubber blade 222 brush 30 cartridge

Claims (12)

[Claims] 1. A process of cleaning an electrostatic latent image formed by charging and image-exposure on a photoconductor, developing the toner image on the photoconductor, transferring the formed toner image onto the photoconductor, and then cleaning the photoconductor. In the image forming method which is repeated, inorganic fine particles are contained in the outermost surface layer of the photoconductor, and the residual toner is cleaned and removed by a rubber blade and a brush-like cleaning member. 2. The particle size of the inorganic fine particles is 0.05 to 2 μm.
The image forming method according to claim 1, wherein the image forming method is m. 3. The image forming method according to claim 1, wherein the inorganic fine particles are hydrophobized. 4. The image forming method according to claim 1, wherein the inorganic fine particles are silica. 5. In an image forming apparatus having a charging device, an image exposing device, a developing device, a transfer separator and a cleaning device around a photoconductor formed on a conductive support, inorganic fine particles are added to the photoconductor. An image forming apparatus characterized in that the toner contained in the outermost surface layer is cleaned and removed by the cleaning device by a rubber blade and a brush-shaped cleaning member. 6. The particle size of the inorganic fine particles is 0.05 to 2 μm.
The image forming apparatus according to claim 5, wherein the image forming apparatus is m. 7. The image forming apparatus according to claim 5, wherein the inorganic fine particles are hydrophobized. 8. The image forming apparatus according to claim 5, 6 or 7, wherein the inorganic fine particles are silica. 9. An image forming apparatus having a charging device, an image exposing device, a developing device, a transfer separator and a cleaning device around a photosensitive member formed on a conductive support, wherein the inorganic fine particles are used as the photosensitive material. The residual toner contained in the outermost surface layer of the body is cleaned and removed by the cleaning device with a rubber blade and a brush-shaped cleaning member, and the photoconductor and the charging device, the image exposure device, the developing device, the transfer separator and the cleaning device. An image forming unit, wherein at least one of the containers is integrally configured as an image forming unit. 10. The particle size of the inorganic fine particles is 0.05 to 2
The image forming unit according to claim 9, wherein the image forming unit has a thickness of μm. 11. The image forming unit according to claim 9, wherein the inorganic fine particles are hydrophobized. 12. The image forming unit according to claim 9, 10 or 11, wherein the inorganic fine particles are silica.