JP2002229234A - Electrophotographic method and electrophotographic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve an electrophotographic method composed of at least an electrifying process for uniformly electrifying a photoreceptor, a latent image forming process by light exposure, a development process performing the development of at least one of a white/black image and a color image, a transfer process for transferring a developed developer image and a cleaning process for removing an untransferred residual toner on the photoreceptor in the overall viewpoint. SOLUTION: At least magnetic toner for performing black development and a non-magnetic toner for performing color development are used as developers used in the development process, the average particle diameter of the toner is controlled to be between 4 μm and 10 μm, an elastic blade is used in the cleaning process and the photoreceptor is formed by laminating successively a photoconductive layer containing amorphous Si and a surface layer on a conductive base body. In the photoreceptor, the surface roughness (Ra) in a square with 10 μm side is controlled to be between 15 nm and 40 nm and the average inclination (Δa) in a square with 10 μm side is controlled to be between 0.12 and 0.40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming an image by uniformly charging an object to be charged, that is, a photosensitive member, and writing image information on the charged surface with visible light, line scanning laser light, or the like. And a color electrophotographic method.

More specifically, the present invention relates to an electrophotographic method in which an amorphous silicon (a-Si) photoreceptor is used and a plurality of colors are developed on the same photoreceptor. The present invention relates to an electrophotographic method for supplying.

[0003]

2. Description of the Related Art Electrophotographic apparatuses have been widely used in addition to conventional so-called copying machines for copying originals, as well as computers and printers as output means of word processors, which have been growing in demand in recent years. It is important for such a printer that a color image output is provided in addition to a conventional monochrome image output.

In such an environment, conventionally, a plurality of developing units each containing a developer of a different color are provided, and one or a plurality of recording cycles are performed on a photosensitive drum serving as an image carrier using an electrophotographic method. A multicolor image forming apparatus has been proposed in which a plurality of color toner images are formed on a recording material, and the plurality of color toner images are collectively transferred and fixed on a recording material to obtain a desired multicolor image.

[0005] 1. Electrophotographic Process FIG. 1 shows one embodiment of the process. Note that this drawing shows a system for performing multicolor development on the same photosensitive member in the multicolor image forming apparatus.

Reference numeral 202 denotes a photosensitive drum which is an image bearing member, and is a drum type electrophotographic photosensitive member which is driven to rotate at a predetermined peripheral speed (process speed) in a clockwise direction indicated by an arrow A. Reference numeral 201 denotes a charging unit for uniformly charging the photoconductor 202.

After the photosensitive member 202 is uniformly charged by the charging means 201, a latent image is formed by the image signal providing means 203, and a visible image (toner image) corresponding to the latent image is formed by the next developing means 204. ) Is formed.

The developing means 204 includes a black developer,
Developing device 204 for developing a color developer
(A) to 204 (d) (each containing a different color toner).

The toner image is separately driven by a drive system 221 and transferred to an intermediate transfer material 222, and then transferred to a final transfer material P made of paper or the like. The intermediate transfer material 222 is
Thereafter, the cleaning is performed by an intermediate transfer material cleaning unit 223 including a cleaning blade 224 and the like, and contributes to the next transfer process.

[0010] The transfer step may be configured to transfer directly to the final transfer material P. In this case, the configuration is different from that in this drawing, for example, the final transfer material P is circulated in the apparatus a plurality of times.

On the other hand, the surface of the photosensitive member 202 is cleaned by a cleaning means (cleaner) 207 after being separated from the transfer material (222 or P) on which the toner image has been transferred. Thereafter, the electrostatic latent image remaining on the surface of the photoreceptor is subjected to charge removal by the charge removing means 208, and then is subjected to the charging step again.

On the other hand, a transfer material P made of paper or the like
05 after passing through the paper feed path 219 of the register roller 22.
The timing is controlled by 0 or the like and supplied to the photoconductor side. Further, the visible image on the surface of the intermediate transfer material 222 (or the photoconductor 202) is transferred to the transfer material P by the transfer means 206 (a),
The transfer material P is separated from the photoreceptor surface by the separating means 206 (b). After the transfer material P is separated, the toner image is fixed by a fixing unit 211 including a roller-212 and the like via a transport system 210, and is discharged out of the apparatus.

The image signal applying means reflects the irradiation light from the light source 215 to the original 213 placed on the original plate 214,
Stored in the scanner 216. In addition, a signal from an external computer or the like is directly stored instead of a document. In response to the stored signal, a latent image light source 217 made of a laser or the like is scanned and intensity-modulated, and is supplied to an image signal providing unit 203 via a polarizing unit such as a mirror 218.

A monitoring electrometer 209 for monitoring the surface potential of the photoconductor 202 is provided as necessary, and feedback is provided to the potential control by the charging means 201 and the image signal applying means 203, for example. The image may be stabilized.

When forming images of multiple colors, that is, two or more colors,
The above steps are repeated as many times as necessary according to the color of the toner to form an image. After forming a plurality of layers of toner images on the transfer material or the intermediate transfer material, if the intermediate transfer material is used, the image is transferred to the final transfer material. Thereafter, an image is output through a fixing process.
In addition, the surface of the photoreceptor has a plurality of charging steps, latent image steps, and developing steps. After each step of charging, latent image, and developing is performed for each color, transfer, separation, cleaning, and static elimination. May be configured to go through a fixing step. Of course, it goes without saying that the image forming apparatus can be used for a single color.

2. a-Si photoreceptor The needs of such color electrophotography include the use of Internet printers and the like, increasing the number of outputs, and output of maps, design drawings, photographs, etc. There is a demand for extremely fine and faithful reproduction without interruption. On the other hand, it is necessary to improve characteristics such as maintenance-free.

As a method for meeting these needs,
JP-B-60-35059, JP-A-54-8374
No. 6, JP-A-60-67951, etc., it is preferable to use an a-Si photosensitive member having excellent durability, high sensitivity, and no pollution.

Examples of color electrophotography using a-Si include tandem type color image forming apparatuses disclosed in JP-A-11-24358, JP-A-11-52599 and JP-A-2000-112203. Proposed. A system for forming an image of a plurality of colors on the same a-Si photoreceptor is proposed in Japanese Patent Publication No. Hei 8-20834.

3. Developing method and developer On the other hand, the developer includes a two-component developer composed of colored particles (toner) contributing to development and a carrier material, and a one-component developer composed of only a toner without a carrier material. Agents. Further, the toner is classified into a magnetic toner containing magnetic particles and a non-magnetic toner not containing magnetic particles.

Various development methods, such as monochrome and color, are devised or adopted for one-component development and two-component brush development depending on the needs. In general, the image reproduction characteristics of the two-component brush development are higher than those of the one-component development. Is considered to be excellent, but each system has its own characteristics. The characteristics of the main developing methods are as follows.

In the following notations, the notations in parentheses relate to toner.

(A) BMI system and FEED system; 1
Component contact development (insulation and magnetism) In particular, the FEED method has almost the same image characteristics as two-component brush development.

(B) Touch-down method; one-component contact development (insulating / non-magnetic) Fogging due to contact development is problematic.

(C) Jumping method: one-component non-contact development (insulation and magnetism) Since there is no contact, there are few problems such as scratches.

(D) Projection method: one-component non-contact development (insulating / non-magnetic) Since there is no contact, there are few problems such as scratches, and since it is non-magnetic, colorization is possible.

(E) Magnedynamic method; one-component contact development (conductive / magnetic) Induction charging by a latent image electric field, brush development Both positive and negative latent images can be developed, but transfer is difficult.

(F) IMB method: two-component contact development (insulating / non-magnetic) Due to the insulating carrier, the reproducibility of fine lines in which charges of opposite polarity are accumulated after development is good.

(G) CMB method; two-component contact development (insulating / non-magnetic) Due to the conductive carrier, solid portions in which reverse polarity charges are not accumulated after development have good reproducibility.

FIGS. 4 and 5 are schematic views showing the inside of the developing means and the vicinity of the area facing the photosensitive member. FIG. 4 shows a developing unit using a one-component developer, and FIG. 5 shows a developing unit using a two-component developer. The developing means 50 includes at least the developer 5
1, a sleeve 52, a blade 53, a developer reservoir 54, and a peeling member 55. FIG. 4 illustrates the case of the magnetic one-component developer, and the magnetic material 5 is provided in the developing three part.
6 are installed. Further, the developing means 50 may have a stirring screw or the like (not shown). The sleeve 52 has a predetermined DC voltage or an AC voltage applied to the DC voltage, and is rotationally driven at a predetermined speed. The developer 51 adheres onto the sleeve 52 from the developer reservoir 54 and is conveyed. Further, the developer 51 passes between the sleeve 52 and the blade 53, is controlled to a predetermined coat thickness, is given a predetermined charge, and is conveyed to a region facing the photoreceptor. It is transported to the opposite area.

In the above-mentioned region, the developer 51 is developed on the surface of the photoconductor by the potential difference between the photoconductor and the sleeve 52 and the applied voltage. The developer 51 remaining on the surface of the sleeve 52 is transferred to the developing unit 50 by the sleeve 52.
Collected inside. Further, the sleeve may be peeled and removed by a removing means such as the peeling member 55. In the one-component development system, the developer 51 is composed of the toner 511, and in the two-component development system, the developer 51 is composed of the toner 511 and the carrier 5.
It consists of 12. Further, both the one component and the two components have external additives (not shown).

In the magnetic one-component developer, as shown in FIG. 4, the blade 53 is made of a magnetic member and is installed at a predetermined distance from the sleeve 52. Therefore, there is little deterioration, which is advantageous in terms of maintenance intervals.

On the other hand, in non-magnetic two-component development, FIG.
As described above, the carrier 512 and the toner 511 are coated on the developing sleeve 52 with a predetermined thickness by the blade 53, and the photosensitive member 100 is formed in a state where a so-called "spike" is formed.
Touch 2. At the contact portion, the toner adheres to the photoreceptor 1002 with an electrostatic force according to the latent image to form a toner image. Good image quality is obtained.

Recently, in a color electron using a digital image signal, a latent image is formed by collecting dots of a constant potential, and a solid portion, a halftone portion and a line portion are formed by changing the dot density. Is expressed.
However, in a state where the toner particles do not adhere to the dots and the toner particles protrude from the dots, it is not possible to obtain the gradation of the toner image corresponding to the dot density ratio of the black portion and the white portion of the digital latent image. There is a problem. Further, when the resolution is improved by reducing the dot size in order to improve the image quality, the reproducibility of a latent image formed from minute dots becomes more difficult, and the resolution and especially the gradation of the highlight portion are increased. The image tends to be poor in quality and lacks in sharpness. In order to cope with such high image quality, a toner having a small particle diameter, specifically, a developer having an average particle diameter of 10 μm or less is suitably used.

For color (other than black) development,
Non-magnetic toners are used to sharpen colors.

Black development is frequently used, and a diameter using a long-life a-Si photoreceptor suppresses maintenance such as carrier replacement, and is practically used and has stable characteristics. Magnetic one-component toners can be used.

The amorphous silicon photoreceptor has a high hardness characteristic unique to the photoreceptor, and a jumping method has been put to practical use. The effect of preventing flaws and the like by this method is synergistic, and is applied to a long life, heavy duty machine. I have.

On the other hand, in the OA market in recent years, the diversification and advancement of information has led to the advancement of colorization of images output in offices, and furthermore, the system has been required to be faster and more stable. -At present, the development of mounting amorphous silicon photoconductors, which are extremely excellent in abrasion resistance and most suitable for ultra-high-speed heavy-duty machines, in color copying machines is underway, taking into account the development status of color developers. It is considered that a combination with the development of the non-magnetic toner is required.

4. Developing System and Developer The image forming system in the digital electrophotographic process is roughly classified into two systems depending on the relationship between image information and an exposure unit. One is an image exposure method (hereinafter, also referred to as IAE) for exposing an image portion, and the other is a background exposure method (hereinafter, BA) for exposing a non-image portion (background portion).
E). In the IAE, a photosensitive member is irradiated with exposure for forming a latent image on a portion corresponding to a recording image area (blackened portion), and a developer is attached to a portion where the surface potential of the photosensitive member is lowered. On the other hand, in BAE, a region corresponding to a background portion (non-blackened portion) is irradiated with light on the photoconductor, and a region where the developer adheres is a region of high surface potential which has not been attenuated.

[0039]

Under the circumstances described above, the following problems are feared.

As for the cleaning performance, the cleaning performance is ensured by adjusting the contact pressure when the cleaning blade contacts the photosensitive member and the contact angle of the cleaning blade.

As described in JP-A-11-24358,
JP-A-11-52599, JP-A-2000-112
A tandem type color electrophotograph such as that of Japanese Patent Publication No. 203,
A photoreceptor corresponding to the type of toner, a charging device, an exposure device, and a cleaning device are required, each of which can be used under optimal conditions. However, the size of the device and the cost are high. Is raised.

In Japanese Patent Application Laid-Open No. 8-137119, a developer having an average particle size of 4.5 to 9.0 μm is used, and the curvature of the surface of the photosensitive member is twice or more the average curvature of the developer. There is disclosed an example in which irregularities having the following characteristics are applied to reduce “fogging”. However, in this publication, the surface shape of the photoreceptor is defined as a macroscopic shape of a developer level (μm order) or more, and particularly when a magnetic developer and a non-magnetic developer are used. No disclosure is made regarding the cleaning properties.

On the other hand, in a system using a plurality of colors, particularly a magnetic toner and a non-magnetic toner, on the same photosensitive member, if the cleaning device is used alone, the characteristics of the magnetic toner and the non-magnetic toner are different. Conditions such as contact pressure required for the above are different.

In the above-described method, if any of the toners is defective in cleaning, or if the contact pressure of the cleaning blade is increased in order to impart sufficient cleaning properties, the toners may be damaged. Rubbing on the surface of the photoreceptor, so-called fusion occurs, external additives or impurities are mixed into the toner, deterioration such as aggregation occurs, and the surface of the photoreceptor is worn or damaged by magnetic toner or the like. There was a case where such troubles occurred.

Japanese Patent Publication No. 8-20834 proposes a method of using a nonmagnetic color toner and a magnetic black toner, disposing a cleaning blade and a magnet roller, and mixing an abrasive with the black magnetic toner. This publication discloses a method of removing the non-magnetic toner at an early stage on the assumption that the non-magnetic toner is fused to the photoreceptor.

However, it is necessary to prevent the occurrence of cleaning failure, which is a cause of fusion or the like, from occurring.
That is, it is important to prevent cleaning failure not only macroscopically but also microscopically. In addition, in particular,
When using a toner having a small particle size of 0 μm or less,
Cleaning is in a more difficult situation, and it has become difficult to cope with the fusing phenomenon of non-magnetic toner and the like, to ensure cleaning performance, and to achieve compatibility with scratches and the like.

Therefore, color electrophotography, especially a-S
When using an i photoreceptor and using completely different types of toners, such as magnetic toners and non-magnetic toners, comprehensive solutions such as cleaning of an electrophotographic process and toner It is necessary to improve the photoreceptor in order to optimize the cleaning in a special condition while improving from the viewpoint.

[0048]

[Means for Solving the Problems] In view of the above situation,
As a result of intensive studies by the present inventors, in an electrophotographic process using a photoconductor obtained by sequentially laminating a photoconductive layer containing at least amorphous Si and a surface protective layer on a conductive substrate, a plurality of photoconductors are formed on the photoconductor. In developing a toner of a kind, the cleaning property and the adhesion resistance of the toner do not necessarily depend on the macroscopic surface shape of the order of μm accompanying the processing of the conductive substrate of the photoreceptor. It has been found that by defining the surface shape of the body microscopically, specifically on the order of several nanometers to several tens of nanometers, it is possible to control toner adhesion, fusing, cleaning properties, scratches, and the like. The correlation with the height Ra and the average inclination Δa was found.

That is, according to the present invention, at least a charging step for uniformly charging the photosensitive member, a latent image forming step by exposure, a developing step for developing at least one of a black and white image and a color image, and a developing step In an electrophotographic method having a transfer step of transferring a transferred developer image and a cleaning step of removing transfer residual toner on a photoreceptor, the developer used in the development step is at least a magnetic material for performing black development. A developer and a non-magnetic developer for performing color development, and the average particle diameter of the toner of the developer is 4 μm or more and 10 μm or more.
μm or less, in the cleaning step, at least an elastic blade is used, the photoreceptor is a photoconductive layer containing at least amorphous Si on a conductive substrate,
And the surface layer is sequentially laminated, and the surface roughness (Ra) of the photosensitive member in a square having a side of 10 μm is 15 nm.
An electrophotographic method characterized by being at least 40 nm or less is provided.

Further, at least a charging step for uniformly charging the photosensitive member, a latent image forming step by exposure, a developing step for developing at least one of a black and white image and a color image, and a transfer of the developed developer image And a cleaning step for removing transfer residual toner on the photoreceptor, the developer used in the developing step includes at least a magnetic developer for performing black development, and a color developer. And an average particle diameter of the toner of the developer is 4 μm or more and 10 μm or less. In the cleaning step, at least an elastic blade is used, and the photoconductor is electrically conductive. A photoconductive layer containing at least amorphous Si and a surface layer are sequentially laminated on a substrate, and the average inclination of the photoconductor in a square having a side of 10 μm (Δ ) Is an electrophotographic method, characterized in that 0.12 to 0.40 is provided.

Further, at least a photoreceptor, charging means for uniformly charging the photoreceptor, a latent image forming means including an exposure light source, and a plurality of developing means for developing at least one of a black and white image and a color image. In an electrophotographic apparatus having a transfer unit for transferring a developed visual image and a cleaning unit for removing transfer residual toner on a photoreceptor, a developer used in the developing unit is at least used for performing black development. And a non-magnetic developer for performing color development, the toner having an average particle size of 4 μm or more and 1 μm or more.
0 μm or less, wherein the cleaning means has at least an elastic blade counter-contacted to the surface of the photoconductor, the photoconductor includes a photoconductive layer containing at least amorphous Si on a conductive substrate, and An electrophotographic apparatus is provided, in which surface layers are sequentially laminated, and the surface roughness (Ra) of the photoreceptor in a square having a side of 10 μm is 15 nm or more and 40 nm or less.

In addition, at least a photoreceptor, charging means for uniformly charging the photoreceptor, a latent image forming means including an exposure light source, and a plurality of developing means for developing at least one of a monochrome image and a color image And a transfer unit for transferring the developed visual image, and a cleaning unit for removing transfer residual toner on the photoreceptor, the developer used in the developing unit performs at least black development. And a non-magnetic developer for performing color development, wherein the toner has an average particle diameter of 4 μm or more and 10 μm or less, and the cleaning means includes at least an elastic blade for the photosensitive blade. What is brought into counter contact with the body surface, the photoreceptor, a photoconductive layer containing at least amorphous Si on a conductive substrate, and a surface layer is sequentially laminated, An electrophotographic apparatus is provided, wherein an average inclination (Δa) of the photoconductor in a square having a side of 10 μm is 0.12 or more and 0.40 or less.

The photoreceptor has a side length of 10 μm.
It is particularly preferable that the surface roughness (Ra) of the m square is 15 nm or more and 40 nm or less, and that the average slope (Δa) of the 10 μm square is 0.12 or more and 0.40 or less.

[0054]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below, but the present invention is not limited thereto.

(Measurement Method) Hereinafter, a measurement method for the photoreceptor, developer and the like of the present invention will be described.

(Surface Shape / Photosensitive Body) The macroscopic surface shape in the present invention is measured using a “Surfcoder SE-3300” manufactured by Kosaka Laboratory Co., Ltd. at a measurement length of 2.5 mm. .

As the surface roughness Ra, JIS B 06
The arithmetic average roughness is measured according to 01. The average inclination Δa is one of the surface form factors, and refers to an average ridge angle (inclination angle) of a convex portion adjacent to a concave portion of a concave and convex portion.
It is defined by the equation (1) described in the section “Definition of terms and parameters of surface roughness”, section 8-12, and is calculated from the three-dimensional shape.

On the other hand, the microscopic surface shape can be measured by an atomic force microscope (AFM) “Q-scope 25 manufactured by Questant Co., Ltd.”
0 ".

In order to measure a microscopic surface shape with high accuracy and good reproducibility, evaluation was performed in a measurement range of the order of μm × μm, and measurement was performed so as to avoid an error due to a curvature gradient (Tilt) of the sample. Preferably the result. In the present invention, evaluation is performed in a measurement range of 10 μm × 10 μm.

Specifically, the T-value of the Q-scope 250
The correction (parabolic) for flattening after fitting the curvature of the AFM image of the sample to the parabola by the ilt Removal mode is given.

The electrophotographic photosensitive member has a uniform cylindrical shape, which is a preferable method. Further, when there is a simmering inclination, a correction for removing the inclination (Line by Line)
I do. As described above, it is possible to appropriately correct the inclination of the sample within a range that does not cause distortion in the data.

Atomic force microscope (AFM; A tomic)
F orce M icroscope), the horizontal resolution (resolution in a direction parallel to the sample surface) is greater than 0.5 nm, the vertical resolution (the resolution in the direction perpendicular to the sample surface) from 0.01 to 0.
It has a thickness of 02 nm and is capable of three-dimensional shape measurement of a sample. The difference from a surface roughness meter that has been widely used in the past lies in its high resolution.

In the range of high resolution as described above, the roughness of the substrate of the photosensitive member is not dominant, but is governed by the properties of the deposited film itself such as the roughness of the photoconductive layer and the surface layer of the photosensitive member. It is possible to evaluate roughness.

The roughness of the photoreceptor substrate depends on the "type" such as "teeth shape" or "processing member" of a lathe, a ball mill, dimple processing, etc., but the roughness of the deposited film itself cannot be expressed by the "type". It is considered that the presence of the shape factor is effective for characteristics such as adhesion to the developer and cleaning properties.

Specifically, the same visual field (10 μm × 10 μm)
m) on a conductive substrate having a surface roughness of less than 9 nm,
An a-Si photoconductor was laminated under various conditions, and the microscopic surface shape of the photoconductor was observed by the AFM. A surface roughness meter widely used for the same measurement, for example, the above Surfcoder S
This is a new index that cannot detect a significant difference with a contact type surface roughness meter such as E-3300.

The present inventors evaluated the same sample in various visual fields in addition to the visual field of 10 μm × 10 μm in the AFM measurement. FIG. 13 shows the correlation between Ra and the visual field. FIG. 14 shows the correlation between the macroscopic surface roughness Rz and the measurement length for reference.

As can be seen from FIG. 13, when the field of view is enlarged, the measured Ra value is stable, but it is difficult to reflect the fine shape due to the influence of the peculiar shape of the sample substrate, such as undulations and projections, and the processed shape. On the other hand, when the field of view is narrowed, the dispersion of the measurement points increases. The same applies to Δa.
Therefore, in the present invention, the result of a 10 μm × 10 μm field of view excellent in the above-described detection performance and overall performance of reproducibility is used.

From the above circumstances, the idea of the present invention is 10 μm.
It is not limited to the field of view of m × 10 μm.

(Surface free energy / photoreceptor) The adhesion of toner, foreign matter, etc. to the surface of the photoreceptor is disclosed in Japanese Patent Application Laid-Open No. H11-31187.
As described in, for example, Japanese Patent Application Publication No. 5 (1993) -105, in the category of physical bonding, an intermolecular force (van der Waals force) is a main factor, and a surface free energy (γ) is a phenomenon on the outermost surface due to an external intermolecular force.

The surface free energy is described in, for example, Vol. 8 (No. 3) and Pages 131-141 (1972) of the Japan Adhesion Society Paper.

In the evaluation of the γ value, a contact angle measuring device “CA-X ROLL” manufactured by Kyowa Interface Co., Ltd. was used, and three kinds of pure water, α-bromonaphthalene, and iocamethylene were used for each sample. Measure the contact angle with the reagent. The obtained contact angle is used for the surface free energy analysis software “EG
The surface free energy (γ) is calculated in the Fowles-3 mode of “−11”.

If the surface free energy measured as described above is too large, the adhesion of the developer and the foreign matter to the foreign matter increases, the releasability from the foreign matter deteriorates, and the cleaning tends to be difficult. On the other hand, in order to obtain a surface layer having a low surface free energy, a technique such as roughening the surface of the substrate of the photoreceptor or using a material having a low surface free energy is used. However, in the former case, a striped image, a so-called moiré, may be generated due to interference of latent image exposure, or the cleaning member may be damaged due to mechanical irregularities. In the latter case, as a material having a low surface free energy, for example, a fluorine-based resin such as Teflon (registered trademark) is used, but as a surface layer used for an a-Si photosensitive member having a long life, This is not preferred from the viewpoint of printing durability.

For the above reasons, the range of the surface free energy is preferably 35 mN / m or more and 55 mN / m or less.

(Spectral Sensitivity / Photosensitive Member) The spectral sensitivity of the photosensitive member refers to the amount of decrease in the potential of the photosensitive member per predetermined amount of light at each exposure wavelength. The spectral sensitivity is measured by changing the wavelength of the image exposure while keeping the potential (dark potential; Vd) in a state where the image exposure is not irradiated, and evaluating the sensitivity of the photoreceptor at each wavelength. I do.

Specifically, the photoreceptor is subjected to a predetermined electrophotographic process by first setting the static elimination light to a predetermined state and controlling the charging means to set Vd to a predetermined value, for example, -450 V (+450 V in the case of positive). Then, while varying the wavelength of exposure for forming a latent image, the amount of decrease in the potential of the photoreceptor is measured by changing the image path light amount at each wavelength (EV measurement).
Specifically, the spectral sensitivity is measured in the range from 400 nm to 900 nm.

(Spectral Reflectance / Photosensitive Member) The reflectance of the photosensitive member surface is measured by measuring the spectral emission intensity I (0) of the spectroscope, then taking the spectral reflection intensity I (D) of the photosensitive member, and calculating the reflectance R = I
(D) / I (0).

Specifically, it refers to the reflectance measured in% mode using a spectrophotometer MCPD-2000 manufactured by Otsuka Electronics Co., Ltd. In order to measure with high accuracy and good reproducibility, it is preferable to fix the detector with a jig so that the light emission / measurement angle is constant with respect to the photosensitive member which is a sample having a curvature.

(Average Particle Size / Developer) There are various methods for measuring the average particle size and the particle size distribution of the toner. As the volume average particle diameter (Dv), a dry dispersion unit RODO was used with a laser diffraction particle size distribution analyzer HELOS (manufactured by JEOL Ltd.).
S (manufactured by JEOL) in combination with a lens focal length of 20
Under the measurement conditions of 0 mm, dispersion pressure of 3.0 × 10 ⁵ Pa, and measurement time of 1 to 2 seconds, the range of particle size of 0.5 μm to 350.0 μm is divided into 31 channels and measured. There is a method in which (median diameter) is determined as a volume average diameter, and the volume% of particles in each particle size range is determined from a volume-based frequency distribution.

Laser diffraction particle size distribution analyzer HELO
S is an apparatus for performing measurement using the Franhofer diffraction principle. In brief, the principle of this measurement is as follows: When a laser beam is emitted from a laser light source to a measurement particle, a diffraction image is formed on the focal plane of the lens on the opposite side of the laser light source. By performing the processing, the particle size distribution of the measurement particles is calculated.

A Coulter Counter TA-II or Coulter Multisizer (manufactured by Coulter Inc.)
Is used. The electrolyte is 1% N using 1st grade sodium chloride.
An aqueous aCl solution is prepared. For example, ISOTON R-I
I (manufactured by Coulter Scientific Japan) can be used. As a measuring method, the electric field aqueous solution 100 to 100
In 150 ml, 0.1 to 5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant,
Further, 2 to 20 mg of a measurement sample is added. The electrolytic solution in which the sample was suspended was subjected to a dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser, and 100 μm was used as an aperture by the measurement device.
Using an m aperture, the volume of toner of 2 μm or more,
The number is measured to calculate a volume distribution and a number distribution. Then, the weight-based weight average particle diameter (D
4) and the volume average particle diameter (Dv) (the median value of each channel is a representative value for each channel).

The particle diameter in the present invention refers to the amount average particle diameter (D4).

(Cleaning Step) Hereinafter, the cleaning step will be described.

(Cleaning) FIG. 12 is a schematic diagram of a cleaning device. The cleaning device includes a cleaning blade 801, a blade holder 806 holding the cleaning blade 801, and a cleaning blade 801.
The control means 802 including a spring or the like for controlling the contact pressure on the photoconductor, the toner reservoir 803, the drivable cleaning roller 804 disposed as necessary, Doctor roller 805-1 for regulating, regulating blade 8
05-2, a transport system for transporting and unloading the cleaned toner, a scooping material for preventing so-called “falling-off”, in which untransferred developer and the like removed by the cleaning blade 801 fall down. Consists of

In the cleaning process, blade cleaning using an elastic member is frequently used because of its simple structure and high cleaning ability. The cleaning of the present invention mainly includes the blade cleaning described above.

Further, in the cleaning according to the present invention,
In cleaning in a state where different types of toners, that is, a magnetic toner and a non-magnetic toner, coexist on the same surface of the photoconductor, it is particularly necessary to control the contact state with the photoconductor surface. Specifically, it is preferable to use the surface shape of the photoreceptor within the specified range. Further, it is preferable to regulate the hardness and angle of the cleaning blade and to control the blade not by the amount of penetration but by the contact pressure and within a prescribed range.

As a result of the study by the present inventors, it has been found that the cleaning by the cleaning blade largely depends on the behavior of the developer in a minute range of the contact portion between the cleaning blade and the photosensitive member.

FIG. 15 is a diagram showing a contact portion between the cleaning blade and the photosensitive member. Photoconductor 1002 is indicated by arrow A
The developer such as the untransferred toner and the external additive is conveyed toward the cleaning blade 1001 on the surface of the photoconductor 1002.

In the vicinity of the contact portion between the cleaning blade 1001 and the photosensitive member surface 1002, a blocking area 1003 made of a developer is formed. The transported toner and the like are decelerated by the blocking area 1003, and the nip is reduced. Intrusion into the part and slip through are suppressed.

FIG. 16 shows a cleaning blade 1001.
FIG. 10 is a model diagram further enlarging a contact portion between the photoconductor 1002 and the photoconductor 1002. The transfer residual developer is on the photoreceptor surface 1002,
The photoconductor is conveyed in the moving direction A on the surface. On the other hand, near the contact portion between the photosensitive member surface 1002 and the cleaning blade 1001, a nip portion 1004 and a blocking region 1003
Are formed, and the developer is cleaned.
The nip portion 1004 mainly includes fine particles such as an external additive, and toner particles may be interposed. At this time, the toner particles are mainly located on the upstream side of the nip portion 1004 and, together with an external additive and the like, appropriately reduce the friction between the cleaning blade 1001 and the photoreceptor surface 1002 to reduce stick-slip (so-called chatter) of the cleaning blade 1001. To prevent or help prevent excessive particles from entering.

On the other hand, the blocking region is formed by the deceleration layer 1003 (a).
And the active layer 1003 (b). Active layer 100
3 (b) mainly contains fine particles such as external additives and a part of toner, and has fluidity. Active layer 1003
By (b), intrusion of excessive toner particles is prevented. The deceleration layer 1003 (a) is composed of toner, external additives, and the like.
In the case of a two-component developer, the carrier material leaked from the developing device may be mixed. The carrier material is generally much larger than the toner particles and is almost completely blocked in the blocking area 1003.

The deceleration layer 1003 (a) decelerates the transfer residual developer conveyed by the photosensitive member surface. Each of the above layers, in particular, the deceleration layer 1003 (a) and the active layer 1003
In (b), it is preferable that the developer such as the toner and the external additive does not aggregate and has fluidity and lubricity. As a result, each layer is maintained uniformly, and excess developer is
Intrusion into the nip 1004 can be suitably prevented.

Generally, a magnetic developer is harder than a non-magnetic developer. As the particles present in the active layer 1003 (b) and the nip portion 1004, a hard material that is not easily deformed by the pressure of a cleaning blade or the like is preferable. From that viewpoint, a carrier material, a magnetic developer, or the like is more preferable than a nonmagnetic toner. preferable.

The width of the nip part 1004 is
003 (a) and the active layer 1003 (b) are maintained and the particles such as the developer are blocked in the nip portion 1004. The larger the size, the more preferable. Due to the increase or the like, stick-slip of the cleaning blade 1001 occurs, or the cleaning blade 1001 and / or the photoconductor 1002
Damage the developer or apply the developer to the photoreceptor surface,
So-called filming and the like tend to occur easily.

From the above viewpoints, the range of the nip width is preferably 10 μm or more and 500 μm or less, and 200 μm or less.
m or less is more preferable.

The deceleration layer 1003 (a) is the active layer 1
The width larger than 003 (b) is preferable because the toner, the external additive, and the like form these layers evenly with respect to the cleaning blade 1001 and maintain good cleaning properties.

When the above-mentioned respective mechanisms work properly, the cleaning property is favorably maintained.

Further, among the particles forming these regions, foreign matters and corona products on the photoreceptor are rubbed and removed particularly by the magnetic toner and the external additive, so that a good image can be obtained for a long period of time. it can.

(Contact Pressure / Cleaning Blade) FIG.
As shown in the figure, the cleaning blade 801 is made of a-Si
In systems where long-life photoconductors such as photoconductors are used and images are formed at high speed, an equalizing blade that can adjust the contact pressure instead of a so-called chip blade fixed to the housing Retention is preferred. The contact pressure of the cleaning blade 801 is controlled by blade control means 802 such as a spring 802.

The contact pressure varies depending on the hardness of the cleaning blade, which will be described later. In general, the higher the cleaning performance, the better the cleaning performance. However, the life may be shortened due to damage to the photoconductor or the blade itself. On the other hand, if the contact pressure is too low, the blade will vibrate, so-called "chatter" will occur, causing uneven wear of the photoreceptor and poor cleaning.
cm (5 to 40 gf / cm) is preferred.

(Contact Angle and Contact Direction / Cleaning Blade) As described above, the cleaning blade contacts the photosensitive member surface. The contact angle in the present invention refers to the tangent X of the photoconductor D and the angle a of the blade 801 shown in FIG.

If the contact angle is too large, toner slips through, and if it is too small, fusing may occur. Specifically, a contact angle of 20 to 50 ° can be suitably controlled. Also, good cleaning properties are maintained.

FIG. 17 shows the cleaning blade 100.
1 is the forward direction to the sightseeing object surface 1002, that is, each contact is 9
FIG. 4 shows a model diagram in the case of contact at 0 ° or more. In the state shown in FIG. 17, the nip portion 1004 is narrower, and the downstream side of the cleaning blade 1001 is sufficiently in contact with the surface of the photoreceptor as compared with FIG. 16 in which the cleaning blade 1001 contacts the sightseeing object surface 1002 with the counter. May not be. Therefore, toner or the like easily enters or slips through the nip portion 1004 from the active layer 1003 (b) and the deceleration layer 1003 (a). In particular, when used at high speed, cleaning failure may occur. In addition, the above-described toner or the like may cause a problem such as abrasion of the surface of the photoconductor.

(Hardness / Cleaning Blade) The higher the hardness (JIS A hardness) of the cleaning blade 801 is, the higher the scraping ability of the photoreceptor surface is, but the uniformity of the entire photoconductor and the damage of the photoreceptor or the blade itself are increased. Disadvantaged.
On the other hand, when the hardness is low, the cleaning property may be reduced due to distortion or the like, or a phenomenon such as the blade being turned up due to friction with the photoreceptor may occur. In particular, the moderation layer 1003 (a), the active layer 1003 (b), and the nip 10
The JIS-A hardness of the cleaning blade 1001 is 5
A preferred range is 5 ° to 85 °.

The active layer 1003 (b) and the deceleration layer 10
In order to form 03 (a), the hardness of the cleaning blade is preferably 55 ° or more. If the hardness is lower than this, the deceleration layer 1003 (a) and the active layer 1003 (b) are not suitably formed, and excessive toner, particularly magnetic toner, etc., sneaks into the nip 1004, causing abrasion of the photoconductor, damage to the blade, and cleaning. Failure may occur.

On the other hand, in the case of high hardness exceeding 85 °,
The low-hardness non-magnetic toner taken into the deceleration layer 1003 (b) sneaks into the nip portion 1004 due to compression in the outer region or the like, causing filming or the active layer 1003.
In some cases, the particles of (b) are aggregated to cause cleaning failure. In addition, the uniformity of the nip portion is reduced, the above layers 1003 to 1004 are not maintained in a suitable state, and the chipping of the blade is liable to occur.

(Cleaning Roller) The cleaning device includes a cleaning roller 804 and a doctor roller 8 for scraping excess toner on the cleaning roller.
It is also preferable to provide a regulating means including the regulating blade 05-1 and the regulating blade 805-2. The cleaning roller 804 preferably reduces the mechanical load on the developer and the photoconductor, and is preferably driven to rotate in the forward direction (the same direction as the photoconductor at the contact portion) with respect to the photoconductor.

If a roller having magnetism, a so-called magnet roller, is used as the cleaning roller, it is effective to separate and collect the magnetic toner.
It is preferable that the driving speed and the driving direction are appropriately adjusted according to the use of the electrophotographic apparatus to be used.

(Exposure Method) In order to further improve the cleaning property, BAE is preferable as the exposure method.

The transfer and separation performance greatly depends on the transfer efficiency and the separation and retransfer latitude. However, in the IAE, the potential of the non-image portion (background portion) is higher than that of the image portion. With regard to, BAE has a wider latitude than IAE.

Further, since the potential of the photosensitive member when entering the cleaning means is attenuated, in the IAE in which the developing is performed on a portion having a low potential, a large amount of the developer tends to adhere to the photosensitive member in the cleaning portion. As for cleaning, the latitude of BAE is wider than that of IAE.

As described above, the BAE is easier to design and, as a result, has the possibility of supplying a stable electrophotographic apparatus having a wide latitude.

(A-Si Photoconductor) Hereinafter, the a-Si photoconductor will be described.

(A-Si photosensitive member) The a-Si photosensitive member is
It comprises a conductive substrate (support) and a photosensitive layer having a photoconductive layer made of a non-single-crystal material having silicon atoms as a base. In addition, a material whose characteristics are improved as necessary is used.

As a means for solving the above-mentioned problem, the present inventors use different photosensitive materials at the same time by using a photosensitive member having a controlled surface fine shape and excellent surface durability. It has been found that the cleaning property at the time of cleaning is maintained well, and extremely suitable image stabilization is achieved over a long period of time. Further, it has been found that by continuously changing the interface composition between the photoconductive layer and the surface layer of the photoreceptor, it is possible to more effectively control the adhesion of the toner.

Further, it is preferable that the spectral reflectance of the photoreceptor satisfies the following equation: 0 ≦ (Max−Min) / (Max + Min) ≦ 0.4 where Min and Max have a wavelength of 450 nm.
The minimum value and the maximum value of the reflectance (%) in the range from to 650 nm are shown, respectively.

(Charge Polarity / a-Si Photoreceptor)
Either a positive polarity or a negative polarity can be used, but from the viewpoint of the electrical characteristics (latent image characteristics) of the photoreceptor, those charged to the negative polarity are preferable.

That is, by using the negative a-Si photosensitive member, optical memory such as ghost can be reduced. A phenomenon in which the history of a part irradiated with image exposure is seen in the next round of the photoconductor is called a ghost. FIG. 7 shows that the ghost when the image exposure wavelength was 660 nm was positive and the negative a
FIG. 6 is a diagram comparing with a -Si photosensitive member. As shown in FIG.
The negative a-Si photoconductor shows better characteristics than the positive a-Si photoconductor. Although the details of the cause are unclear, holes move in the photoreceptor layer in the positively charged positive a-Si, whereas in the negative a-Si photoreceptor, electrons having high mobility are transferred to the photoreceptor layer. It is difficult to trap optical carriers generated during the latent image process because of moving inside, or the trapped optical carriers are easily swept out in the next charging process, and the optical memory is reduced. Conceivable.

(Exposure Wavelength / a-Si Photoconductor) It is preferable that the exposure light source mainly has a single wavelength centered on a short wavelength equal to or shorter than the spectral sensitivity peak wavelength of the photoconductor.

That is, as a result of evaluating the image exposure wavelength dependence of the ghost with respect to the above-mentioned photoreceptor, it was found that the use of the photoreceptor at a wavelength shorter than the spectral sensitivity peak wavelength enables more effective ghost manifestation. There was found. Figure 1 shows the results
It is shown in FIG. FIG. 11 shows the spectral sensitivity of the a-Si photosensitive member and the ghost at each wavelength.

As shown in FIG. 11, the a-Si photosensitive member has a spectral sensitivity peak at about 700 nm, while the ghost is effectively reduced when the wavelength is shorter than the spectral sensitivity. You can see that there is. On the short-wavelength side below the spectral sensitivity peak wavelength, the image carrier is generated at a shallow position in the thickness direction of the photoreceptor by image exposure, so that the above-described hole having a small mobility moves in the direction of the surface layer. Is shortened, and the ghost is considered to be effectively reduced. Conversely, on the longer wavelength side than the spectral sensitivity peak, photocarriers are generated up to a deep region on the substrate side, and holes move long distances to the surface layer side, so that the above-described effects tend to be reduced.

(Layer Configuration / a-Si Photoconductor) FIG. 6 is a schematic configuration diagram for explaining the layer configuration of the photoconductor.

The photosensitive member 6 for an image forming apparatus shown in FIG.
00 denotes a photosensitive layer 6 on a substrate 601 for a photosensitive member.
02 is provided. The photosensitive layer 602 is made of a-Si: H,
It is composed of a photoconductive layer 603 made of X and having photoconductivity.

FIG. 6B is a schematic configuration diagram for explaining another layer configuration. Photoreceptor 600 for image forming apparatus
A photosensitive layer 602 is provided on a substrate 601 for a photosensitive member.
Is provided. The photosensitive layer 602 includes a photoconductive layer 603 made of a-Si: H, X and having photoconductivity, and an amorphous silicon (604) and / or amorphous carbon (604 ′) surface layer.

FIG. 6C is a schematic configuration diagram for explaining another layer configuration of the photosensitive member for an image forming apparatus. The photoconductor 600 for an image forming apparatus includes a substrate 601 for the photoconductor.
The photosensitive layer 602 is provided thereon. Photosensitive layer 602
Represents a photoconductive layer 603 made of a-Si: H, X and having photoconductivity, an amorphous silicon-based (604) and / or
Alternatively, an amorphous silicon-based (604 ') surface layer, an amorphous silicon-based charge injection blocking layer 605 between the photoconductive layer 603 and the substrate 601, and a photoconductive layer 603 and the surface layer 604 and / or 604' And a charge injection blocking layer 605 ′.

FIGS. 6 (d) and 6 (e) are schematic diagrams for explaining still another layer configuration of the photosensitive member for an image forming apparatus. The photosensitive member 600 for an image forming apparatus has a photosensitive layer 602 provided on a substrate 601 for a photosensitive member. The photosensitive layer 602 is composed of a-S constituting the photoconductive layer 603.
i: a charge generation layer 607 and a charge transport layer 608 made of H and X, an amorphous silicon-based (604) and / or amorphous carbon-based (604 ′) surface layer, a portion between the photoconductive layer 603 and the base 601, and And / or the photoconductive layer 603 and the charge injection blocking layers 605 and 605 ′.

FIG. 6F is a schematic configuration diagram for explaining still another layer configuration of the photosensitive member for an image forming apparatus.
The photosensitive member 600 for an image forming apparatus has a photosensitive layer 602 provided on a substrate 601 for a photosensitive member. The photosensitive layer 602 includes a charge generation layer 607 and a charge transport layer 608 made of a-Si: H, X constituting the photoconductive layer 603;
And an amorphous silicon-based (604) and / or amorphous carbon-based (604 ′) surface layer. Although not particularly shown, the charge injection blocking layers 605 and 605 ′ may be provided between the photoconductive layer 603 and the base 601 and / or between the photoconductive layer 603 and the charge injection blocking layer.

Examples of the method for producing the a-Si photosensitive member include a glow discharge method (an AC discharge CVD method such as a low-frequency CVD method, a high-frequency CVD method or a microwave CVD method, or a DC discharge CVD method), a sputtering method, and the like. It can be formed by various thin film deposition methods such as a vacuum evaporation method, an ion plating method, a photo CVD method, and a thermal CVD method. Since it is relatively easy to control the conditions for manufacturing a photoreceptor for an image forming apparatus having desired characteristics, a glow discharge method, particularly a high-frequency glow using a power supply frequency in an RF band, μW band or VHF band, is used. The discharge method is preferably used.

(Support) The substrate may be either conductive or electrically insulating. Examples of the conductive substrate include various metals and alloys thereof, such as stainless steel. In addition, a substrate obtained by conducting a conductive treatment on at least the surface of the electrically insulating substrate on the side on which the photosensitive layer is formed can also be used.

Further, the shape of the substrate can be a cylindrical or plate-like endless belt having a smooth surface or an uneven surface. The thickness is appropriately determined so that a desired photoconductor for an image forming apparatus can be formed.

In particular, when performing image recording using coherent light such as laser light, image defects due to so-called interference fringe patterns appearing in a visible image in a range where the photogenerated carriers are not substantially reduced are reduced. A technique for effectively eliminating the error may be used.

Specifically, JP-A-60-168856
JP-A-60-178457, JP-A-60-178457
Unevenness may be provided on the surface of the substrate by a known method described in JP-A-225854, JP-A-61-231561 and the like.

An interference preventing layer or region such as a light absorbing layer may be provided in the photosensitive layer or below the photosensitive layer.

The fine roughness of the surface of the photoreceptor can be controlled by making the surface of the substrate finely scratched. The scratches may be formed using an abrasive, etching by a chemical reaction, so-called dry etching in plasma, sputtering, or the like.

As described above, the method of treating the surface of the substrate does not necessarily affect the microscopic surface shape of the photosensitive member, as described above.

(Photoconductive Layer) The photoconductive layer contains atoms for controlling the conductivity as necessary, for example, in order to impart characteristics according to the charging polarity used or to widen the latitude of manufacturing stability. (Doped).

When doping atoms for controlling conductivity, they may be contained in the photoconductive layer in a uniformly distributed state, or may be contained in a non-uniform distribution state in the layer thickness direction. There may be parts that are.

As the atoms for controlling the conductivity, so-called impurities in the field of semiconductors can be cited, and the atoms belonging to Group 13 of the periodic table (p.
(Group 15 atoms) or atoms belonging to Group 15 of the periodic table (Group 15 atoms) that provide n-type conduction characteristics can be used.

Specific examples of Group 13 atoms include boron (B), aluminum (Al), gallium (Ga), indium (In), and thallium (Tl). Fifteenth
As the group atoms, specifically, phosphorus (P), arsenic (As),
Examples include antimony (Sb) and bismuth (Bi).

The thickness of the photoconductive layer is appropriately determined as desired from the viewpoint of obtaining desired electrophotographic characteristics and economic effects, and is preferably 15 to 50 μm, more preferably 18 to 45 μm, and optimally Desirably, the thickness is 20 to 40 μm.

(Surface Layer) It is preferable to further form an amorphous silicon-based and / or amorphous carbon-based surface layer on the photoconductive layer formed on the substrate as described above. This surface layer has a free surface, and is provided to achieve the object of the present invention mainly in moisture resistance, continuous repeated use characteristics, electrical pressure resistance, use environment characteristics, and durability.

The surface layer is made of amorphous silicon carbide (a-SiC:
H, X) and one of amorphous carbonized, oxidized and nitrided
Amorphous silicon containing at least one species (a-SiCON: H,
Materials such as X) are preferably used.

In addition, it is preferable to use an amorphous carbon film (aC: H) mainly composed of carbon as the surface layer. Furthermore, it is preferable to use an amorphous carbon film (aC: H: F) having a bond with fluorine inside and / or on the outermost surface.

AC: H has excellent water repellency and low friction, has a high hardness equal to or higher than that of a-SiC, and has an image in a high humidity environment even when the environmental countermeasure heater is removed. This has the effect of preventing blurring. Further, it has excellent releasability and is effective for cleaning properties such as toner removal properties. Further, for example, the incorporation of a halogen atom such as a fluorine atom is effective for water repellency, reduction of friction, and the like.
F has remarkable effects of water repellency and low friction.

Further, the surface layer may contain atoms for controlling conductivity as necessary. As the atom for controlling the conductivity, a Group 13 atom or a Group 15 atom can be used as in the case of the photoconductive layer.

One or more of carbon, oxygen, nitrogen and conductivity controlling atoms may be uniformly contained in the surface layer or may be contained in the thickness direction of the surface layer. There may be a portion having a non-uniform distribution such that the amount changes. Also, between the photoconductive layer and the surface layer, carbon atoms,
A layer (upper intermediate layer) in which the content of oxygen atoms and nitrogen atoms is lower than that of the surface layer may be provided. Further, a region where the composition varies may be provided in the interface region between the surface layer and the photoconductive layer. These are effective for improving the adhesion between the surface layer and the photoconductive layer and for improving the electrical characteristics. The thickness of the surface layer is usually 0.01 to 3 μm, preferably 0.05 to 2 μm, and most preferably 0.1 to 1 μm. If the layer thickness is less than 0.01 μm, the surface layer is lost due to abrasion or the like during use of the photoreceptor, and if it exceeds 3 μm, a decrease in electrophotographic properties such as an increase in residual potential may be observed. .

With the structure of the surface layer as described above, the electrical characteristics and high-speed continuous usability can be dramatically improved, and a high hardness of the surface layer can be secured.

(Charge Injection Blocking Layer) A charge injection blocking layer (lower injection blocking layer UBL; Un) which functions to block charge injection from the conductive substrate side between the conductive substrate and the photoconductive layer.
der Blocking Layer) and a charge injection blocking layer (upper injection blocking layer TB) between the photoconductive layer and the surface layer, which functions to prevent charge injection from the surface layer side.
L; Top Blocking Layer). These charge injection blocking layers have a function of preventing charges from being injected into the photoconductive layer side from the substrate side or the surface layer side when the photosensitive layer is subjected to a charging treatment of a fixed polarity on its free surface. are doing. The same atoms as those of the photoconductive layer can be used as the atoms for controlling the conductivity contained in the charge injection blocking layer. In the present invention, the thickness of the charge injection blocking layer is preferably from 0.05 to 5 μm, more preferably from 0.1 to 4 μm, and most preferably from the viewpoints of obtaining desired electrophotographic characteristics and economic effects. It is desirable that the thickness be 0.5 to 3 μm.

In addition, for the purpose of further improving the adhesion, an adhesion layer or a light absorbing layer for preventing generation of an interference pattern due to light reflected from the substrate may be provided.

(A-Si Photoreceptor Manufacturing Apparatus) Each of the above layers is manufactured by a known apparatus and a film forming method as shown in FIGS. 2 and 3, for example.

FIG. 2 shows a power supply frequency of 13.56 MHz.
RF plasma CVD using an RF band (hereinafter referred to as "R
FIG. 2 is a schematic configuration diagram illustrating an example of an apparatus for manufacturing a photoconductor for an image forming apparatus by using “F-PCVD”.

This apparatus is roughly classified into a deposition apparatus 310
0, source gas supply device 3200, reaction vessel 3111
Inside, the base 3112, the base heater 3113,
A source gas introduction pipe 3114 is provided, and a high frequency matching box 3115 is further connected.

A high-frequency plasma CVD (VHF-PC) using a VHF band frequency of 50 to 450 MHz as a power source.
An apparatus for manufacturing a photoreceptor for an image forming apparatus formed by the VD) method is, for example, an RF-type photoconductor in the manufacturing apparatus shown in FIG.
It can be obtained by replacing the PCVD deposition apparatus 3100 with a deposition apparatus 4100 shown in FIG.

In FIG. 3, reference numeral 4112 denotes a base, 4113
Is a heater for heating the substrate, 4114 is a raw material gas introduction pipe,
4115 is an electrode, 4120 is a motor for rotating the substrate, 4
121 indicates an exhaust pipe, and 4130 indicates a discharge space.

The source gas supply device 3200 includes source gas cylinders 3221 to 226, valves 3231 to 236,
3241 to 246, 3251 to 256 and mass flow controllers 3211 to 216,
Each source gas cylinder is connected to a gas introduction pipe 3114 in a reaction vessel 3111 via a valve 3260.

The a-Si photosensitive member is sequentially deposited and formed by a known plasma CVD method or the like using the above-described apparatus.

Further, as described above, the microscopic surface roughness of the photoreceptor is adjusted by adjusting various manufacturing conditions such as plasma power, flow rate of raw material gas, degree of vacuum and temperature, and film forming speed resulting therefrom. It is achieved by changing.

The photoreceptor for an image forming apparatus designed to have the above-described structure exhibits extremely excellent electrical, optical and photoconductive characteristics, image quality, durability and use environment characteristics.

(Developer) The developer will be described below.

(Magnetic and Non-magnetic) One-component and two-component developers, magnetic and non-magnetic developers, and the features of the developing system using them are as described above.

In the present invention, in the color electrophotographic process, a black one-component magnetic toner, which is durable and can obtain stable image quality even at high speed, is used.
In order to clarify the color, it is preferable that the color developer does not contain black or dark magnetic particles, that is, uses a non-magnetic toner.

(Black Developer / Magnetic One Component) One-component and two-component developers, magnetic and non-magnetic developers, and the features of the developing system using them are as described above. Also, 2
In the component developer, a magnetic carrier is used as a carrier.

In the present invention, as the black developer,
It has been put into practical use, and from the viewpoint of its high-speed stability,
Components, ie, magnetic one-component developers, are preferred.

(Color Developer / Non-Magnetic Two-Component) On the other hand, the non-magnetic color developer uses a non-magnetic toner as described above. It is considered that a two-component developer composed of a toner is superior, and a two-component developer is particularly preferable as a developer used in high-speed, heavy-duty electrophotography as in the present invention. In addition, since the toner has a carrier material, it is easier to control the level of adhesion to the developing sleeve than in the case of a single component, and it is preferable because scattering of toner from the sleeve can be suppressed particularly when used at high speed.

(Particle Size) As described above, it is preferable that the toner has a small particle size of 10 μm or less. On the other hand, when the diameter is small, cleaning becomes difficult, transfer efficiency is reduced, and non-uniformity of an image may occur.
Is a preferable range.

(Production Method of Black Developer) The magnetic one-component developer, which is a black developer, can be produced by a known production method.

As an example of the production method, a binder resin, a magnetic substance, a release agent, a charge control agent, and other components necessary for toner and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill. Then, using a heat kneader such as a heating roll, kneader, or extruder, melt and knead the resin to mutually compatibilize with each other, disperse or dissolve other toner materials such as magnetic material, cool, solidify, and pulverize. rear,
Classification and, if necessary, surface treatment can be performed to obtain toner particles. Either the classification or the surface treatment may be performed first. In the classification step, it is preferable to use a multi-divider classifier in terms of production efficiency.

The pulverizing step can be performed by a method using a known pulverizing apparatus such as a mechanical impact type or a jet type.
In order to obtain a toner having a specific circularity, it is preferable to further apply heat and pulverize, or to subject the toner to auxiliary mechanical shock. Further, a lusting method in which finely pulverized (classified as necessary) toner particles are dispersed in hot water, a method in which the toner particles pass through a hot air flow, or the like may be used.

Further, magnetic fine particles can be contained as the magnetic material. Such magnetic fine particles may be any material that exhibits magnetism or is magnetizable, such as metals such as iron, manganese, nickel, cobalt, and chromium, magnetite, hematite, various ferrites, manganese alloys, and other ferromagnetic materials. Alloys and the like, and their average particle size is 0.05 to 5 μm, more preferably 0.1 to 2 μm.
It can be used as a fine powder of μm. The amount of the magnetic fine particles contained in the magnetic powder is preferably from 15 to 70% by mass, more preferably from 25 to 45% by mass, based on the total mass of the developing powder. The magnetic material is generally black or brown close to black, and also functions as a black colorant. Further, external additives such as strontium titanate (ST) and silica are appropriately added.

(Production Method of Color Developer) The toner of the non-magnetic two-component developer is basically the same as the above-described magnetic one-component developer, provided that no magnetic material or magnetic fine particles are contained. Further, a desired color toner can be produced by using a well-known colorant.

Further, as a method for producing a carrier, a known carrier generation method can be used.

For example, there is a method in which nickel zinc ferrite having an average particle diameter of 60 μm coated with a silicone resin is mixed with 100 parts by mass of 6.5 parts by mass of the toner.

The external additives can be transferred in the same manner as the above-described magnetic one-component developer. In this example, ferrite is used as the carrier, but iron powder or the like may be used.

By using the above-mentioned items alone or in combination, it is possible to obtain excellent effects.

[0174]

EXAMPLES The effects of the present invention will be specifically described below with reference to examples. Note that the present invention is not limited to these examples.

(Experimental Example 1) The apparatus for manufacturing a photosensitive member for an electrophotographic apparatus by the RF-PCD method shown in FIG.
An a-Si based photoreceptor comprising a charge injection blocking layer, a photoconductive layer, and a surface layer was prepared on an 8 mm (φ108) mirror-finished aluminum cylinder under the conditions shown in Table 10.
Furthermore, the mixing ratio and total flow rate of SiH ₄ and H ₂ of the photoconductive layer,
Various photoconductors were produced by changing film forming conditions such as discharge power (plasma power) and substrate temperature.

Further, various photoconductors were manufactured by using a manufacturing apparatus based on the VHF-PCD method shown in FIG.

The thickness of the photoconductor is adjusted by adjusting the thickness of the photoconductive layer 603. In addition to the total thickness of 30 μm shown in Table 10,
10 μm, 20 μm and 40 μm were prepared.

The laminated samples were randomly selected, and the microscopic surface roughness Ra and the macroscopic surface roughness Rz were measured using the surf coder SE-3300 described above with a measurement length of 2.5 mm.
Compared. The method of measuring the surface roughness is as described above. Table 13 shows the results. From Table 13, the microscopic roughness Ra which is a characteristic unique to the deposited film has no correlation with the macroscopic roughness Rz.

As an example of the result of the microscopic surface shape, Ra when the discharge power is varied is shown in FIG. The results are shown in Tables 1 to 9. From Tables 1 to 9, it can be seen that the surface shape of the deposited film itself under the film forming conditions is not detected by the macroscopic surface shape.

FIG. 1 shows Δa when the substrate temperature was changed.
9 and FIGS. 20 and 21 show the results of Ra and Δa when the total film thickness is varied.

In addition to the conditions shown in FIGS.
It can be controlled by the above various conditions.

From these, it can be seen that the fine surface shape (Ra, Δa) can be controlled by the film forming conditions including the film thickness.

(Experimental Example 2) The apparatus for manufacturing a photosensitive member for an electrophotographic apparatus by the RF-PCD method shown in FIG.
Table 1 on a mirror-finished aluminum cylinder
An a-Si photoreceptor comprising a charge injection blocking layer, a photoconductive layer, and a surface layer was prepared under the conditions shown in Table 0 and Table 11. Table 1
0 is a photoconductor of negative polarity, and Table 11 is an example of manufacturing conditions of a photoconductor of positive polarity. Furthermore, various photoconductors were produced by changing the film forming conditions such as the mixing ratio and the total flow rate of SiH ₄ and H ₂ of the photoconductive layer, the discharge power (plasma power), and the substrate temperature.

[Evaluator / φ108] As an evaluator, Canon GP605 was changed to a laser having a wavelength of 670 nm for latent image exposure, the resolution was set to 1200 dpi, and the static elimination light was changed to an LED having a peak wavelength at 660 nm. . The exposure method remains GP605, that is, IA
E. As a charging unit, a corona charger for GP605 was used. Further, the conditions for applying voltage or current, the amount of exposure for static elimination exposure and latent image exposure, and the process speed of each charging unit were made variable. The cleaning roller was removed from the cleaning means, and the cleaning blade contact pressure was made variable. Furthermore, remodeling of transfer means, developing means, etc. is performed,
A color electrophotographic apparatus having the configuration shown in FIG. 1 was used.

The evaluation of the surface potential of the photoreceptor was carried out using TRe.
Using a non-contact surface potentiometer “344” manufactured by K Company, it was installed at the position of the developing means 204 and measured. At this time, the photoconductor was set so that the distance between the electrometer probe and the surface of the photoconductor matched the distance between the developing means and the photoconductor.

As the toner, a toner normally used in GP605 was used. The present evaluation machine is provided with a belt-shaped transfer means, but may be a roller-shaped transfer means or may be provided with a separation means.

[Evaluation of Charging Ability and Dark Decay] The charging ability was determined by fixing the surface temperature of the photoreceptor, the amount of static elimination, and the application conditions of the main charging unit to predetermined conditions, and irradiating the latent image without irradiation.
Average surface potential (V) for one rotation of the photoconductor at the position of the developing means
d).

In this example, the surface temperature of the photoreceptor is 25 ° C., the light elimination light amount is 2.3 μJ / cm ² , and the charging means is −1000.
A current of μA (+1000 μA for positive polarity) was applied.

At this time, the surface potential at the upstream development position 204 (a) is defined as the charging ability, and this potential and the downstream development position 20 (a) are used.
The difference from the surface potential in 4 (b) to 4 (d) was defined as dark decay (Vdd).

[Evaluation of Optical Memory] For the optical memory, the surface potential (V
d) and the average surface potential (Vl) for one round of the photoconductor when the latent image exposure is applied is adjusted to be a predetermined value.
It was measured as a potential difference between the surface potential of the photoreceptor after one round of irradiation of the latent image exposure of 1 and the surface potential when the latent image exposure was not irradiated. In this experimental example, the light elimination light amount was changed in addition to the predetermined light amount, and Vd in each state was reduced by -450.
V (+450 V for positive polarity) and Vl were set to -50 V (+50 V for positive polarity).

[Sensitivity Evaluation] In the sensitivity characteristic evaluation, the same Vd was set as in the evaluation of the optical memory, the amount of latent image exposure was gradually changed from no irradiation, and the potential drop due to each irradiation light was measured. The amount of light when the average potential of the photoreceptor is reduced to a half of Vd is Vh light amount, and the amount of light when the average potential is reduced to Vl potential (−50 V, +50 V for positive polarity) is Vl. The amount of light is smaller, and the smaller the amount of light, the higher the sensitivity of the photoreceptor.

[Evaluation of Potential Unevenness] In the evaluation of the potential unevenness, the potential difference (maximum value−minimum value) of one rotation of the photoconductor is determined by setting the potential difference (ΔV) of Vd (ΔV
(drot), Vh light quantity and Vl light quantity were irradiated, and Vh potential unevenness (ΔVhrot) and Vl potential unevenness (ΔVlrot) were obtained.

While moving the electrometer probe in the longitudinal direction of the photoreceptor in the image forming area, V
d, Vh, and Vl were measured, and the difference between the average potentials in the longitudinal direction of the photoconductor (maximum value-minimum value) was defined as Vd, Vh, and Vl potential longitudinal unevenness (ΔVdax, ΔVhax, ΔVlax).

[Evaluation of Temperature Characteristics] The temperature characteristics were determined by measuring the charging ability while changing the temperature of the photosensitive member from room temperature to about 45 ° C., and measuring the change in charging ability per 1 ° C. temperature.

The photosensitive member produced was set in the above-mentioned evaluation machine, and the charging ability, the temperature characteristic, the optical memory, and the sensitivity characteristic were evaluated at the process speed of 300 mm / sec by the above-mentioned methods. The results are shown in FIGS.

From the above, the sensitivity is almost the same depending on the charging polarity of the photoreceptor, but the charging ability is slightly better and the dark decay is less with the negative polarity. This is an advantageous characteristic in a system in which the developing means is sequentially installed on the photoconductor and a system using an a-Si photoconductor having dark decay.

Further, in the temperature characteristics, and particularly in the optical memory, the negative a-Si photosensitive member has a positive a-
It was found that the characteristics were better than those of the Si photoreceptor. In particular, in electrophotography according to the present invention which performs multicolor development and color output, an image is often output, and the optical memory characteristic is one of the important characteristics. In terms of environmental stability,
A negative a-Si photosensitive member having a small temperature characteristic is effective.

(Experimental Example 3) The wavelength of the latent image exposure 203 and the static elimination light 208 were set to the same wavelength for the negative a-Si photosensitive member of Experimental Example 1, and these wavelengths were changed to change the sensitivity and the exposure of the optical memory. The wavelength dependence was evaluated. Also, as in Experimental Example 2, the cleaning device of the electrophotographic apparatus of FIG. 1 was excluded, and pre-discharge light consisting of halogen light was installed at the position, and the discharge light 208 as in the case of the sensitivity and optical memory described above. The evaluation was performed by changing the wavelength. In this experimental example, the rate of decrease in charging ability is the charging ability in the case of only the pre-static light,
It refers to the rate of decrease in charging ability when the charge removing light 208 is irradiated. The exposure wavelength dependence of the optical memory was also evaluated for positive a-Si.

The results are shown in FIG. Note that the spectral sensitivity and the rate of decrease in charge indicate the relative ratio to the peak value, and the optical memory indicates the relative ratio to the positive a-Si photosensitive member.

From this result, on the long wavelength side which is equal to or longer than the peak wavelength of the spectral sensitivity, the effect of reducing the optical memory decreases, and the positive a-
It can be seen that an optical memory close to the Si photoconductor has occurred. In addition, the charging ability has been reduced. Although the detailed cause is unknown, on the long wavelength side above the spectral sensitivity, photocarriers are generated in the depth direction (substrate side) in the thickness direction of the photoconductor, so that holes having low mobility (holes) are formed. It is considered that the increase in the distance traveled by the vehicle causes a decrease in the overall carrier traveling performance.

Therefore, it is preferable to use on the short wavelength side below the spectral sensitivity peak.

Example 1 An apparatus for manufacturing a photoreceptor for an electrophotographic apparatus by the RF-PCD method shown in FIG.
A negative-polarity a-Si system having various Ras according to Experimental Example 1 on an aluminum cylinder having a mirror-finished surface of 8 mm (φ108) or on a transparent substrate obtained by adding a transparent electrode such as ITO to a glass cylinder. A photoreceptor was produced.
The total thickness of the photoconductor is 2 for the photoconductor of the aluminum cylinder.
The thickness was 0 to 40 μm. On the other hand, the photoreceptor of the transparent substrate is made of a thin film for both the charge injection blocking layer and the photoconductive layer, and by adjusting the manufacturing conditions, a thin-film photoreceptor having a surface fine shape equivalent to that of an aluminum cylinder and transmitting visible light is obtained. Produced.

A black developer is NP675 manufactured by Canon.
A magnetic one-component developer for yellow, cyan,
The developer of each color of magenta is Canon CLC1100
Two-component developers were used.

Further, as the evaluator, the evaluator used in Experimental Example 3 was used. Each of the photoconductors using the aluminum cylinders prepared in the above-described evaluation machine was set, and 350 mm /
The evaluation was performed at a process speed of sec using the above-described developers of black toner, yellow, cyan, and magenta.

Of the produced photoreceptors, the charging ability was 450 V
As described above, the optical memory is within 3 V, the temperature characteristic is within 2 V / ° C.,
In addition, potential unevenness (ΔVd, ΔVh, ΔVl; ax, ro
The following evaluation was carried out by regarding those having a voltage of 10 V or less as acceptable.

The cleaning means is the same as that described in JIS-
A hardness of 70 degrees was used, the contact angle was 25 °, and the contact pressure was 98 mN / cm (10 gf / cm).

Using these photoconductors, a normal environment (N /
N; 23 ° C./50% RH), and a durability test of 250K sheets was performed using a color original of 5% duty. In this durability test, 10K, 20K, 50K, 100K, 150
At the time of K, 200K, and 250K, using a two-color (half-tone / white) chart, observe the image, the photosensitive member surface, and the cleaning device by forming a halftone in a mixture of four colors. The defectiveness of the cleaning and the state of the cleaning blade were determined. The criteria are as follows.

Regarding the image, in addition to visually judging the image quality, a change in image density due to the developer passing through the cleaning device, a local change in image density in the form of “fog” or stripes “CL”
"N defective streaks" were measured. The image density was measured on a solid white image and a halftone image with a reflection densitometer manufactured by Macbeth.

The image quality at the initial stage and at the time of 10K was evaluated on a 5-point scale under the following conditions. At this time, no damage such as chipping of the cleaning blade was observed.

Level 5 (very good); fog maximum, both within 1% on average; CLN defective streaks, no black spots; Level 4 (good); fog up to 1.5%, average within 1%, and CLN defect streaks, no black spots, level 3 (somewhat good); fog max. 2%, average 1.5% and
CLN defect streaks, black spots within 1.5 mm length and within 3 places, level 2 (no practical problem); fog up to 3%, average within 2% and CL
N defective streaks, black spots Within 2 mm length and within 5 locations, level 1 (possible for practical problems); fog or CLN defective streaks, black spots are outside the above range.

Further, before and after the endurance, the image quality, the cleaning device, the state of the photoreceptor, and the like were evaluated. The symbols in Table 1 are as follows.

◎: very good cleaning property, very good No blade chipping Cleaning property rank 5 including fogging and no decrease in image running level, 〜 to ：: good cleaning property better than conventional blade chipping is fine No chipping, no developer slipping through Cleanability rank on image 4, ○: Slightly better Cleaning performance is slightly better than before. ●, 従 来: Cleanability equal to or less than that of conventional blades missing Chip cleaning rank 2 or less on the image.

The process speed is set to 100 mm / s
ec to 500 mm / sec, the same durability evaluation was performed, and the design latitude was evaluated. Table 1 shows the results. The criteria are as follows.

◎ ◎: Very large latitude. Very good cleaning performance irrespective of process speed. ◎, ◎: Large latitude. Good cleaning performance irrespective of process speed. The durability cleaning performance at each process speed is ◎ to ○ The fluctuation of cleaning performance rank on the durability image is within 1, ○: Somewhat large latitude The cleaning performance is good regardless of the process speed The durability cleaning performance at each process speed is good ○ Fluctuation of cleaning property rank on the durable image is within 2 ●: Normal or lower latitude Other than the above.

Table 1 shows the results from the initial stage, 10K, and each evaluation time, and the evaluation results of the design latitude. From Table 1, good results were obtained.

[0216]

[Table 1] In the case of a photoreceptor using a transparent substrate, the surface potential of the photoreceptor is set to be as low as the total thickness of the photoreceptor, and the bias applied to the developing means is adjusted to be substantially equivalent to that of a photoreceptor using an aluminum cylinder. Development was done.

Further, the cleaning section was irradiated with strong exposure to allow the photosensitive member to pass therethrough. In the state shown on the left, the behavior of the cleaning unit was observed from the inside of the photoconductor. A schematic diagram of the results is shown in FIG. FIG. 22 shows the cleaning blade 100.
1 and the vicinity of the contact portion between the photosensitive member surface 1002 as viewed from the back side of the photosensitive member.
And can be seen. In the second half of the nip portion, an uneven distribution area 1005 of the developer is seen. The shape of the boundary between the blocking region 1003 and the nip 1004 and the shape of the non-uniform distribution region 1005 are considered to be caused by the undulation of the cleaning blade 1001 and the penetration of toner particles and the like.

By using the Ra (roughness height) of the photoreceptor surface within the specified range, fine particles such as external additives are appropriately supplied to the nip portion 1004, and the deceleration layer 100
In No. 3, the toner particles escaped in a direction deviated from the direction of travel of the photoreceptor, so that excessive collision with the cleaning blade and sneaking in could be prevented, and good cleaning properties could be maintained.

Further, it was possible to prevent sticking and agglomeration between the magnetic toner and the non-magnetic toner, which are thought to be due to the suppression of the collision force, and it was possible to prevent poor cleaning and damage to the blade.

Example 2 Various Δa values were obtained in accordance with Experimental Example 1.
A negative-polarity a-Si photoreceptor having the following formula was prepared. The same electrical characteristics evaluation was performed on these photoconductors using the same evaluator as in Example 1, and the charging performance, optical memory, temperature characteristics,
Use a photoconductor that has passed the potential unevenness, and
50 mm / sec and process speed 2
The durability was evaluated up to 50K. Table 2 shows the results.

[0221]

[Table 2] From Table 2, good results were obtained. Further, as a result of observation using a transparent substrate photoconductor, by using the photoconductor surface Δa (concavo-convex inclination) within a specified range, the movement of the cleaning blade in the nip portion 1004 becomes smooth, and the speed is reduced. Layer 1003 (a) or active layer 1003
In (b), the toner particles are not fixed to the surface of the photoreceptor and have fluidity. In particular, fine particles such as the magnetic toner, the carrier material, and the additive material may be dispersed in the active layer 1003 (b) or the nip portion 10.
By being suitably supplied to No. 04, good cleaning properties could be maintained.

Further, the carrier material, the external additive, and the like at the upstream side of the nip portion 1004 flowed favorably from the active layer 1003 (b), thereby preventing poor cleaning and damage to the blade.

Example 3 The production conditions of Example 1 were adjusted to produce negative-polarity a-Si photosensitive members having various Ra and Δa. These photoconductors were evaluated for electrical properties in the same manner as in Example 1. Using photoconductors that passed the charging ability, optical memory, temperature characteristics, and potential unevenness, they were processed at 350 mm / sec and process as in Example 1. The durability was evaluated up to 250K by varying the speed. The results are shown in the upper row of Table 3. From the upper part of Table 3, very good results were obtained.

[0224]

[Table 3] Good latitude was also obtained. In the present embodiment, a deceleration layer 1103 (a) and an active layer 11 are further used in the cleaning section from the inside of the photoconductor using a transparent substrate.
03 (b), the behavior of the developer and the cleaning blade at the nip 1104 was observed. As a result of the 250K durability test, the blade contact state at the boundary between the active layer 1003 (b) and the nip 1104 is stable, and the developer sneaks into the cleaning blade due to the collision of the untransferred developer and the toner after the nip. Slip-through was prevented. This tendency is also apparent in the evaluation of the latitude with varying the process speed, and the latitude of the cleaning property has been widened.

Example 4 Photoconductors having various surface free energies were manufactured by further adjusting the photoconductor production conditions of Example 3. Furthermore, as shown in Table 12, as the surface layer, a surface layer containing amorphous carbon as a main component or a surface layer containing fluorine atoms (collectively referred to as an aC-based surface layer) is used. Laminated photoconductors were also used.

[0226] A passable product having the same evaluation as in Example 1 was used, and the same durability evaluation as in Example 1 was performed. Table 4 shows the results. From Table 4, very good results were obtained.

[0227]

[Table 4] In addition, as a result of observing the state in the cleaning section using the transparent substrate, as shown in FIG.
(B), the blade contact state at the boundary of the nip portion 1104 was more stable. Further, there was almost no aggregation of the toner. By using the photoreceptor surface free energy within the specified range, the adhesive force of the developer is reduced,
It is considered that the collision with the cleaning blade was reduced, the collision between the magnetic toner and the non-magnetic toner was suppressed, and the aggregation and the like were prevented.

(Example 5) Of Examples 1 to 3, the photoreceptors were arbitrarily selected, and the hardness of the cleaning blade was varied, and the same evaluation was performed. Table 5 shows the results.

[0229]

[Table 5] In this example using a cleaning blade having a JIS-A hardness of 55 to 85 degrees, good results were obtained. There was no undulation of the cleaning blade, and the uneven distribution area 1005 was also small. In addition, there was no damage to the cleaning blade itself, no filming, etc., a good cleaning state was maintained, and the design latitude was also a good result.

Example 6 Using the same photoreceptor as in Example 5, a magnet roller provided with a magnetic toner was added as a cleaning roller to the cleaning device in the above-described evaluation apparatus. It was driven in the direction (the same direction at the contact part). In this state, durability evaluation and design latitude evaluation were performed as in Examples 1 to 3. Table 6 shows the results.

[0231]

[Table 6] Good results were obtained. By cleaning roller
The toner was appropriately supplied to the cleaning blade, and the deceleration layer 1003 (a) and the active layer 1003 (b) were formed stably, and good cleaning properties were maintained. Further, while the magnetic roller and the non-magnetic toner are decelerated by the cleaning roller, external additives and excess magnetic toner are swept out from the rear of the cleaning roller to the surface of the photoconductor,
Magnetic toner and external additives are distributed in the active layer 1003 (b), particularly in the vicinity of the nip and in the nip 1004, so that the cleaning property is suitably maintained.

Further, the deceleration layer 1003 (a) of the developer
By controlling the collision with the active layer 1003 (b) or the cleaning blade, the aggregation and the like of the magnetic toner and the non-magnetic toner are particularly suppressed. Further, for example, 1% Du
Even when an image having a small image ratio is output, the particles are supplied to the cleaning blade.
The latitude for images has also expanded.

(Example 7) In the same manufacturing method as in Example 3, when the surface layer 604 of the photoreceptor is laminated, the composition with the lower layer is continuously changed to change the wavelength from 450 nm to 65 nm.
With light in the range of 0 nm, the spectral reflection at the above interface portion is 0 ≦ (Max−Min) / (Max + Min) ≦ 0.
An interface-less photoreceptor satisfying No. 4 was produced.

The electrical characteristics were evaluated in the same manner as in Example 1, and the photoconductors that passed the evaluation of the temperature characteristics, optical memory, etc. were used for the following evaluations.

As a result of performing the same durability evaluation as in Example 1, as shown in Table 7, good results were obtained.

[0236]

[Table 7] Further, a 250 K durability test was performed by forming an isolated dot having an image ratio of 25% or outputting a halftone image composed of a Keima pattern. As a result, good cleaning properties were obtained. Further, as a result of observation from the back side of the photoreceptor, it was found that fogging, which is a nucleus of toner adhesion on the photoreceptor surface before reaching cleaning, and sharpness of an image were improved.

By eliminating the interface as shown in FIG. 25 depending on the presence or absence of the interface, the amplitude of the spectral reflectance is reduced. When the thickness of the surface layer is changed, each line in FIG. 25 shifts right and left.

When viewed at the same wavelength, the presence of the interface is
The change in reflectance when the surface layer thickness changes is large, that is, the change in sensitivity due to this is large.

By eliminating the interface, substantial sensitivity fluctuations due to substantial unevenness in the film thickness of the latent image exposure / incident exposure path due to the surface fine roughness are suppressed, and become the core of toner aggregation and adhesion. It is considered that fog was prevented and the sharpness of an image such as an isolated dot was improved.

Example 8 A photoreceptor having an interface-less photoreceptor whose Ra, Δa, and surface free energy were adjusted in the same manner as in Example 7 was prepared by adjusting the production conditions. further,
The evaluation device was provided with a cleaning roller composed of a magnet roller, and the hardness of the cleaning blade was varied. In this state, as in the other examples, the design latitude was evaluated based on the durability at 250K paper passing and the durability with the process speed varied. Table 8 shows the results.

[0241]

[Table 8] From Table 8, good results were obtained. Also, in the cleaning section, particularly in the active layer 1003 (b), the developer rotates and has a suitable fluidity, so that excessive collision with the cleaning blade and intrusion into the cleaning blade are prevented. .

In addition to the N / N environment, H / H (35 ° C. /
In each environment of 85% RH) and N / L (23 ° C./5% RH), a continuous printing durability test of 500K sheets was performed for a cleaner-less and cleaner-less system without replacing the cleaning blade.

As a result, good cleaning properties were maintained. In addition, the deceleration layer 1103 (a), the active layer 1103
(B) was also formed uniformly in the longitudinal direction of the cleaning blade 1101, and was interposed with fluidity.

Further, no undulation, chipping or damage of the cleaning blade, fogging or fusing on the photoreceptor were observed.

Example 9 By further adjusting the manufacturing conditions shown in Table 11, a positive photosensitive member having the same surface shape as in Example 3 was produced. The evaluation machine was the same as in Example 3 except that the evaluation machine was modified to BAE.

These photosensitive members were evaluated for electrical characteristics in the same manner as in Example 3, and were evaluated for charging ability, optical memory, temperature characteristics,
Use a photoconductor that has passed the potential unevenness, and
50 mm / sec and process speed 2
The durability was evaluated up to 50K. The results are shown in the middle of Table 3. Results of Example 3 using IAE (upper row in Table 3)
Even better results were obtained.

The latitude was also very good. Using a transparent substrate, the deceleration layer 1103 (a) and the active layer 110 in the cleaning section from the inside of the photoreceptor
3 (b), the behavior of the developer and the cleaning blade at the nip 1104 was observed.

As a result of the 250K durability test, the active layer 1003
(B), the blade contact state at the boundary of the nip portion 1104 was stable, and it was very well prevented from sneaking into the cleaning blade due to the collision of the transfer residual developer and the like, and the toner passing through the nip portion. This tendency is also evident in the latitude evaluation with varying process speed, and the latitude of the cleaning property has been widened.

Example 10 As the photoconductor, the negative photoconductor used in Example 3 was used. On the other hand, the developer used in Examples 1 to 9 was changed from the charge control agent and the external additive (silica) to silica for positive toner. Also,
The carrier material for the two-component developer was changed to a fluororesin-coated carrier. Thus, a positive polarity developer was prepared. The same photoconductor as the photoconductor used in Example 3 was used for the photoconductor and the evaluation machine.

The photosensitive members were evaluated for electrical characteristics in the same manner as in Example 3 to determine the chargeability, optical memory, temperature characteristics,
Use a photoconductor that has passed the potential unevenness, and
50 mm / sec and process speed 2
The durability was evaluated up to 50K. The results are shown in the lower part of Table 3. Even better results were obtained than the results of Example 3 using IAE (upper row of Table 3).

The latitude was also very good. Using a transparent substrate, the deceleration layer 1103 (a) and the active layer 110 in the cleaning section from the inside of the photoreceptor
3B, behaviors of the developer and the cleaning blade at the nip 1104 were observed.

As in the case of the ninth embodiment, as a result of the endurance of 250K, the blade contact state at the boundary between the active layer 1003 (b) and the nip portion 1104 is stabilized, and the cleaning blade is hit against the cleaning blade due to the collision of the transfer residual developer. Penetration and slippage of the toner after the nip portion were very well prevented.
This tendency is also evident in the latitude evaluation with varying process speed, and the latitude of the cleaning property has been widened.

(Comparative Example) A photoreceptor was manufactured by varying Ra and Δa, and the same durability evaluation as in Example 1 was performed on a photoreceptor which passed the electrical characteristic evaluation of Example 1. Results, Table 9
As shown in Table 2, the results were equal to or less than those of the conventional method.

[0254]

[Table 9] FIG. 24 is a schematic diagram of the vicinity of the cleaning unit viewed from the back side of the photoconductor. As shown in FIG.
(B) and the active layer 1103 (b) are non-uniform, and the non-magnetic toner is
In many cases.

Further, the uneven distribution area 1005 of the nip portion caused by the undulation of the cleaning blade was widened.

When Ra and Δa are too large, the fluidity of the developer in the deceleration layer 1003 (a) and the active layer 1003 (b) is low, and the non-magnetic toner adheres strongly to the magnetic toner. Deterioration of the developer, such as rubbing or the external additive being buried in the non-magnetic toner, and deterioration of the cleaning property, such as chipping or slipping of the cleaning blade, were observed. on the other hand,
In a system in which Ra and Δa are too small, in particular, the active layer 1003
In (b), the rotation of the developer was small. In particular, the non-magnetic toner collided with the cleaning blade and sunk, and fusion occurred due to the pressure of the cleaning blade and the like.

In any case where Ra and Δa are too large or too small, the toner tends to agglomerate and adheres to the surface of the cleaning blade or the photoreceptor, which is a factor of deterioration of the cleaning property. Easy to do.

In the durability of the H / H and N / L environments, in addition to the phenomenon of N / N, stick-slip of the cleaning blade sometimes occurred.

[0259]

[Table 10]

[0260]

[Table 11]

[0261]

[Table 12]

[0262]

[Table 13]

[0263]

As described above, in electrophotography in which a magnetic developer and a non-magnetic developer of a small particle size of 4 to 10 μm are developed on the same photoreceptor and cleaned, the fine surface shape of the photoreceptor and other factors are reduced. By using the surface properties and cleaning constitution of the above in the specified ranges, extremely suitable image stabilization was obtained.

Specifically, the fine surface shape (Ra, Δa) of the photosensitive member was defined. In addition, the cleaning configuration such as surface free energy and the hardness of the elastic cleaning blade, the exposure wavelength to be used, and the configuration such as the reflectance of the surface of the photoreceptor are specified. In such a state, when the magnetic developer and the non-magnetic developer are mixed, the cleaning quality is maintained well, a high-quality image is stably obtained for a long period of time, and the deterioration of the developer and the cleaning blade. The image quality is prevented from deteriorating, and maintenance-free is further promoted.

As an unexpected effect, the number of image defects or the growth of defects due to protrusions on the photoreceptor was reduced. It is considered that fine abnormal discharge and the like are prevented by improving the fluidity of the developer in the cleaning section.

Further, abrasion of the surface layer of the photosensitive member was reduced. In the cleaning section, which contributes to the wear of the photoreceptor, microfluidic friction between the cleaning section and the photoreceptor is reduced due to the fluidity of the developer and the good presence of particles in the nip portion, and the abrasion is reduced. It is considered that was suppressed.

Further, in order to suppress the above-mentioned image defects, the wear of the surface of the photoreceptor is suppressed, so that damage such as protrusions is suppressed, and a region having low resistance is exposed or the protrusions come off. Is considered to be prevented, and the growth of image defects is suppressed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an example of an electrophotographic apparatus.

FIG. 2 is a schematic diagram for explaining an example of an RF-PCVD manufacturing apparatus.

FIG. 3 is a schematic diagram for explaining an example of a VHF-PCVD manufacturing apparatus.

FIG. 4 is a schematic diagram for explaining an example of a developing device using a one-component developer.

FIG. 5 is a schematic diagram for explaining an example of a developing device using a two-component developer.

FIG. 6 is a schematic cross-sectional view illustrating an example of a layer configuration of an a-Si photoconductor.

FIG. 7 is a diagram showing optical memory characteristics of an a-Si photosensitive member.

FIG. 8 is a diagram showing temperature characteristics of an a-Si photoconductor.

FIG. 9 is a diagram illustrating charging characteristics of an a-Si photoconductor.

FIG. 10 is a diagram illustrating sensitivity characteristics of an a-Si photoconductor.

FIG. 11 is a diagram showing the sensitivity of the negative polarity a-Si photosensitive member and the spectral characteristics of the optical memory.

FIG. 12 is a schematic diagram for explaining an example of a cleaning device.

FIG. 13 is a diagram showing a correlation between a microscopic surface shape Ra and a visual field.

FIG. 14 is a diagram showing a correlation between a macroscopic surface shape Rz and a visual field.

FIG. 15 is a schematic perspective view for explaining a cleaning model.

FIG. 16 is a schematic enlarged view for explaining a contact portion between a cleaning blade and a photoconductor.

FIG. 17 is a schematic enlarged view for explaining a contact portion between a cleaning blade and a photoconductor.

FIG. 18 is a diagram showing a correlation between a microscopic surface shape Ra and discharge power.

FIG. 19 is a diagram showing a correlation between a microscopic surface shape Δa and a substrate temperature.

FIG. 20 is a diagram showing a correlation between a microscopic surface shape Ra and a total film thickness.

FIG. 21 is a diagram showing a correlation between a microscopic surface shape Δa and a total film thickness.

FIG. 22 is a schematic diagram illustrating a cleaning model viewed from the back side of the photoconductor.

FIG. 23 is a schematic diagram illustrating a cleaning model as viewed from the back side of the photoconductor.

FIG. 24 is a schematic diagram illustrating a cleaning model viewed from the back side of the photoconductor.

FIG. 25 is a diagram illustrating an example of spectral reflection data.

[Explanation of symbols]

 Reference Signs List 50 developing means 51 developing material 52 developing sleeve 53 blade 54 developer pool 55 peeling member 56 magnetic member 201 charging / wearing means 202 photoconductor 203 image signal applying position 204 (a) developing means 204 (b) developing means 204 (c) Developing unit 204 (d) Developing unit 205 Feeding system 206 (a) Transfer unit 206 (b) Separating unit 207 Cleaning unit (cleaner) 208 Static elimination unit 209 Monitor electrometer 210 Transport system 211 Fixing unit 212 Fixing roller 213 Document 214 Platen 215 Image reading light source 216 Scanner 217 Image signal light source 218 Mirror 219 Feed path 220 Register roller 221 Drive system 222 Intermediate transfer material 223 Intermediate transfer material cleaning means 224 Intermediate transfer material cleaning blade 511 Toner 512 Carrier 600 Photoconductor 601 Conductive substrate 602 Photosensitive layer 603 Photoconductive layer 604 a-Si based surface layer 604 ′ aC surface layer 605 Lower blocking layer 605 ′ Upper blocking layer 606 Free surface 607 Charge generation layer 608 Charge transport Layer 801 Cleaning blade 802 Control means 803 Toner pool 804 Cleaning roller 805-1 Doctor roller 805-2 Restriction blade 806 Cleaning blade holder 1001 Cleaning blade 1002 Photoconductor surface 1003 Blocking area 1003 (a) Deceleration layer 1003 (b) Active layer 1004 Nip portion 1005 Unexpectedly uniform region of particle distribution 3100 Deposition device 3111 Reaction vessel 3112 Base (support) 3113 Heater for base (support) 3114 Source gas inlet tube 3115 Height Frequency matching box 3200 Source gas supply device 3211 Mass flow controller 3212 Mass flow controller 3213 Mass flow controller 3214 Mass flow controller 3215 Mass flow controller 3216 Mass flow controller 3221 Source gas cylinder 3222 Source gas cylinder 3223 Source gas cylinder 3224 Source gas cylinder 3225 Source gas cylinder 3232 Source gas cylinder 3232 Source gas cylinder 3232 Gas cylinder valve 3233 Source gas cylinder valve 3234 Source gas cylinder valve 3235 Source gas cylinder valve 3236 Source gas cylinder valve 3241 Gas inflow valve 3242 Gas inflow valve 3243 Gas inflow valve 3244 Gas inflow valve 3245 Gas inflow valve 3246 gas inflow valve 3251 gas outflow valve 3252 gas outflow valve 3253 gas outflow valve 3256 gas outflow valve 3260 valve 3261 pressure regulator 3262 pressure regulator 3263 pressure regulator 3264 pressure regulator 3265 pressure regulator 3266 pressure regulator 4100 Deposition apparatus 4112 Substrate (support) 4113 Heater for substrate (support) 4114 Source gas introduction pipe 4115 Electrode 4120 Motor for rotating substrate (support) 4121 Exhaust pipe 4130 Discharge space a Contact angle A Traveling direction of photoconductor surface D Photoconductor P Final transfer material X Photoconductor tangential direction

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/04 G03G 21/00 312 21/10 318 (72) Inventor Kazuhiko Takada 3-chome Shimomaruko, Ota-ku, Tokyo 30-2 Canon Inc. (72) Inventor Toshiyuki Ehara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Hironori Owaki 3-30-2 Shimomaruko, Ota-ku, Tokyo F term (reference) in Canon Inc. 2H005 AA02 AA21 EA05 FA02 2H068 DA01 DA20 DA23 DA37 FA14 FB11 FC03 2H076 CA00 DA37 2H134 GA01 GB02 HA01 HD01 HD04 HD05 HD06

Claims (22)

[Claims] At least a charging step of uniformly charging a photosensitive member, a latent image forming step by exposure, a developing step of developing at least one of a black and white image and a color image, and transferring the developed developer image In the electrophotographic method having a transfer step to perform, and a cleaning step to remove transfer residual toner on the photoreceptor, the developer used in the development step, at least a magnetic developer for performing black development,
A non-magnetic developer for performing color development, the toner having an average particle size of 4 μm or more and 10 μm or less,
In the cleaning step, at least an elastic blade is used, and the photoconductor is formed by sequentially laminating a photoconductive layer containing at least amorphous Si and a surface layer on a conductive substrate, and the photoconductor has a square shape of 10 μm on a side. Wherein the surface roughness (Ra) is 15 nm or more and 40 nm or less. 2. At least a charging step of uniformly charging a photoconductor, a latent image forming step by exposure, a developing step of developing at least one of a black and white image and a color image, and transferring the developed developer image In the electrophotographic method having a transfer step to perform, and a cleaning step to remove transfer residual toner on the photoreceptor, the developer used in the development step, at least a magnetic developer for performing black development,
A non-magnetic developer for performing color development, the toner having an average particle size of 4 μm or more and 10 μm or less,
In the cleaning step, at least an elastic blade is used, and the photoconductor is formed by sequentially laminating a photoconductive layer containing at least amorphous Si and a surface layer on a conductive substrate, and the photoconductor has a square shape of 10 μm on a side. Wherein the average slope (Δa) is 0.12 or more and 0.40 or less. 3. The electrophotographic method according to claim 2, wherein the surface roughness (Ra) of the photoconductor in a square having a side of 10 μm is 15 nm or more and 40 nm or less. 4. The photoreceptor has a surface free energy of 3
4. The electrophotographic method according to claim 1, wherein the electrophotographic method is 5 mN / m or more and 55 mN / m or less. 5. The electrophotographic method according to claim 1, wherein the photoconductor is charged to a negative polarity. 6. The electrophotographic method according to claim 1, wherein said non-magnetic developer is a two-component developer comprising a carrier and a toner. 7. The JIS-A hardness of the elastic blade is:
2. The method according to claim 1, wherein the angle is 55 degrees or more and 85 degrees or less.
7. The electrophotographic method according to any one of claims 1 to 6. 8. The electrophotographic method according to claim 1, wherein the cleaning step includes a cleaning step using a roller. 9. The exposure apparatus according to claim 1, wherein the exposure is exposure mainly based on a single wavelength centered on a short wavelength equal to or shorter than a spectral sensitivity peak wavelength of the photoconductor. Electrophotographic method. 10. The electrophotographic method according to claim 1, wherein the spectral reflectance of the photoconductor satisfies the following expression. 0 ≦ (Max−Min) / (Max + Min) ≦ 0.4 (wherein Min and Max are 6 from wavelength 450 nm)
The minimum value and the maximum value of the reflectance (%) in the range of 50 nm are shown, respectively. ) 11. The apparatus according to claim 1, wherein the exposure for forming the latent image is a background exposure (BAE).
The electrophotographic method according to any one of the above. 12. A photoconductor, a charging unit for uniformly charging the photoconductor, a latent image forming unit including an exposure light source, and a plurality of developing units for developing at least one of a black and white image and a color image. In an electrophotographic apparatus having a transfer unit that transfers a developed visual image and a cleaning unit that removes transfer residual toner on a photoreceptor, the developer used in the developing unit needs to perform at least black development. And a non-magnetic developer for performing color development, the toner having an average particle diameter of 4 μm or more and 10 μm or less.
μm or less, the cleaning means is at least an elastic blade is brought into counter contact with the surface of the photoconductor, the photoconductor is a photoconductive layer containing at least amorphous Si on a conductive substrate, and An electrophotographic apparatus, wherein a surface layer is sequentially laminated, and the surface roughness (Ra) of the photoconductor in a square having a side of 10 μm is 15 nm or more and 40 nm or less. 13. A photoconductor, a charging unit for uniformly charging the photoconductor, a latent image forming unit including an exposure light source, and a plurality of developing units for developing at least one of a black-and-white image and a color image. In an electrophotographic apparatus having a transfer unit for transferring a developed visual image and a cleaning unit for removing transfer residual toner on a photoreceptor, a developer used in the developing unit is at least used for performing black development. And a non-magnetic developer for performing color development, the toner having an average particle diameter of 4 μm or more and 10 μm or less.
μm or less, the cleaning means is at least an elastic blade is brought into counter contact with the surface of the photoconductor, the photoconductor is a photoconductive layer containing at least amorphous Si on a conductive substrate, and An electrophotographic apparatus, wherein surface layers are sequentially laminated, and the average inclination (Δa) of the photoconductor in a square having a side of 10 μm is 0.12 or more and 0.40 or less. 14. The electrophotographic apparatus according to claim 13, wherein a surface roughness (Ra) of the photoconductor in a square having a side of 10 μm is 15 nm or more and 40 nm or less. 15. The surface free energy of the photoconductor is:
The electrophotographic apparatus according to any one of claims 12 to 14, wherein the electrophotographic apparatus has a range of 35 mN / m to 55 mN / m. 16. An electrophotographic apparatus according to claim 12, wherein said photosensitive member is charged to a negative polarity. 17. An electrophotographic apparatus according to claim 12, wherein said non-magnetic developer is a two-component developer comprising a carrier and a toner. 18. The electrophotographic apparatus according to claim 12, wherein the elastic blade has a JIS-A hardness of 55 ° or more and 85 ° or less. 19. An electrophotographic apparatus according to claim 12, wherein a cleaning roller is disposed in said cleaning means. 20. The exposure light source according to claim 12, wherein the exposure light source mainly has a single wavelength centered on a short wavelength equal to or shorter than a spectral sensitivity peak wavelength of the photoconductor.
9. The electrophotographic apparatus according to any one of 9 above. 21. The electrophotographic apparatus according to claim 12, wherein the spectral reflectance of the photoconductor satisfies the following expression. 0 ≦ (Max−Min) / (Max + Min) ≦ 0.4 (wherein Min and Max are 6 from wavelength 450 nm)
The minimum value and the maximum value of the reflectance (%) in the range of 50 nm are shown, respectively. ) 22. The exposure apparatus according to claim 12, wherein the exposure for forming the latent image is a background exposure (BAE).
2. The electrophotographic apparatus according to claim 1.