JPH11237819A - Image forming device - Google Patents

Abstract

(57) Abstract: An image forming apparatus capable of preventing toner fusion and filming film on the surface of a photosensitive drum and performing good cleaning. An image forming unit that forms a toner image on an image carrier, an image transfer unit that transfers the toner image on the image carrier to a transfer material, and an image transfer unit that transfers the toner image to the transfer material by the image transfer unit Cleaning means for removing transfer residual toner on the image carrier, wherein the image carrier is an amorphous silicon-based photoconductor, and the cleaning means is an elastic blade, and the elastic blade has a temperature of 5 ° C. The elastic material has a rebound resilience of 45% or less at 45 ° C. and a temperature dependence of the rebound resilience of −1% / in a range of ６０60 ° C. and in a region where the physical properties of the elastic blade show a rubbery state. de
g to + 1% / deg.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using an amorphous silicon photosensitive member as an image carrier.

[0002]

2. Description of the Related Art In recent years, multifunction peripherals having all output terminals such as copiers, printers, and faxes have been widely accepted in the market. Although an electrophotographic system has been widely accepted as such a network-compatible output terminal, one of the major problems is an increase in the duty cycle of the main body. The duty cycle is the limit number of sheets that the main body can continue to operate normally without serviceman maintenance, and one of the most limiting factors is the life of the photosensitive drum. Also, from the viewpoint of ecology, eliminating waste, that is, reducing consumables, extending the life of consumables, and increasing reliability have become our absolute issues. Furthermore, digitization has progressed from conventional analog devices, and it has become an absolute issue for us to reduce the cost of the main unit to be equal to or less than the analog.

Under such circumstances, an amorphous silicon photoreceptor as an image carrier has a high hardness (Vickers hardness of 1000 kg / m ² or more according to JIS), durability, heat resistance, and the like.
Because of their excellent environmental stability, they are increasingly used, and are indispensable especially for high-speed machines that require high reliability.

However, in this type of apparatus, it is not only toner that affects the image quality by adhering to the surface of the image carrier, but also fine paper powder generated from paper that is almost always used as a transfer material. Foreign matter adhering to the surface of the image carrier due to organic components precipitated, corona products generated due to the presence of high-pressure members in the device, etc., reduces resistance especially in a high-humidity environment and forms a clear electrostatic latent image This is considered to be a factor that causes deterioration of image quality.

It is known that the above-described image deterioration phenomenon easily occurs in the case of an amorphous silicon photoreceptor formed by film formation by glow discharge decomposition of silanes. In order to avoid such a drawback, particularly when a one-component magnetic toner is used, a magnet roller is disposed in the cleaning device on the upstream side of the cleaning blade as viewed in the running direction of the image carrier. A magnetic brush is formed with a part of the toner collected in the apparatus, and the magnetic brush is brought into contact with the surface of the image carrier to supply the magnetic toner again.
There has been proposed a configuration in which various foreign substances as described above are rubbed and removed by a polishing action of toner particles at a blade portion. Such a means is a method in which the polishing action is less locally biased on the surface of the image carrier, compared to a method of rubbing the surface of the image carrier with a separately prepared abrasive using a web, a rubber roller, or the like. The deterioration of the carrier surface is also small. For example, the above-mentioned method can be combined with an auxiliary means such as disposing a heater on the image carrier and reducing the peripheral humidity during night and standby to prevent the surface of the image carrier from having low resistance. There is a certain effect in preventing image degradation due to the above-mentioned causes.

In an image forming apparatus in which the process of transferring a transferable toner image formed on the surface of an image carrier to a transfer agent mainly composed of paper is repeated, the image does not transfer to a transfer material during transfer, and remains on the image carrier. It is essential that the residual toner be sufficiently removed each time.

For this reason, various cleaning means have hitherto been proposed. A cleaning means in which the residual toner is scraped off by a cleaning blade made of an elastic material such as urethane rubber has a simple and compact structure. It is widely used because of its low cost and excellent toner removal function. As a rubber material for cleaning blades, it has high hardness and rich elasticity, abrasion resistance, mechanical strength, oil resistance, ozone resistance,
Outstanding urethane rubber is commonly used.

[0008]

However, first, in recent years, there has been a tendency to reduce the particle size of toner in recent years in order to improve image quality. Further, from the viewpoint of energy saving, low power fixing is indispensable due to reduction in power consumption of the main body, particularly power of the fixing heater and high productivity, and the melting point of toner is also being reduced.

On the photoreceptor after the transfer, there is a residual toner of 90% to 95% of the toner transferred to the transfer material by the transfer charger. The transfer residual toner adheres to the photoreceptor by electrostatic force and physical adhesion. As the toner becomes finer, the cohesive force of the toner increases and the adhesive force between the surface of the photoconductor and the toner increases. As a result, the load on the cleaning blade increases. In particular, the upstream side of the cleaning blade edge portion (the portion indicated by reference numeral A in FIG. 5).
The toner agglomerated gradually accumulates due to durability. Where the amount of accumulation is large, it becomes impossible for the blade edge to form a uniform contact (nip) with respect to the photoreceptor, resulting in poor cleaning. In addition, the load on the photoconductor at the edge of the cleaning blade changes compared to the area where the accumulated amount is locally large, and the transfer residual toner on the photoconductor is locally entangled. Will cause toner fusion. As described above, as the toner particle size becomes smaller, the surface area with respect to the volume increases, so that the toner is more susceptible to the influence of the ambient temperature, and toner fusion occurs on the photoconductor.

Second, conventionally, a mag roller 22 is disposed upstream of the cleaning blade as shown in FIG.
(1) Rubbing of the transfer residual toner on the photoreceptor, (2) Recoating of the toner on a white background portion and a paper interval portion where the transfer residual toner is relatively small on the photoreceptor, and (3) Scratching off by a cleaning blade. It has been considered to perform functions such as collecting collected toner and (4) transferring waste toner to a waste toner conveying screw. However, in the present study, the portion where the transfer residual toner on the photoreceptor is large is rubbed and collected by the mag roller by the mag roller, and the toner is re-coated on the photoreceptor from the mag roller where the transfer residual toner hardly exists. However, it was found that the toner on the mag roller was redeveloped by the surface potential difference between the white background portion and the black background portion on the photoconductor. It has been found that the toner amount of the re-development by the mag roller differs depending on the image condition, and as a result, the above-described problem at the edge of the cleaning blade, that is, uneven filming and toner fusion occur.

As described above, fine paper powder generated from paper used in most cases as a toner and a transfer material, organic components precipitated from the paper, corona products generated due to the presence of high-pressure members in the apparatus, etc. In this way, an oxidized layer is formed on the surface of the photoreceptor with durability by foreign matter adhering to the surface of the image carrier, and absorbs moisture in a high-humidity environment and lowers resistance to prevent formation of a clear electrostatic latent image, which leads to deterioration of image quality. It is a factor.

It has been confirmed in our experiments that the endurable surface oxide layer is about 30 ° to 80 °.
However, in our experiment,
The surface oxidized layer reaches about 30 ° to 80 °, after which the film thickness hardly changes, but as the durability progresses, the image deterioration was initially eliminated by dry wiping, water wiping, and alcohol wiping. , It turned out to be no longer eliminated. Further, the surface of the drum, which has been durable in such a state, has a thickness of 0.1 mm.
It was found that image deterioration would not be eliminated without polishing with abrasives such as cerium oxide (CeO ₂ ) of about 3 μm to ₂ μm dispersed in alcohol or the like. This is particularly noticeable when the drum heater is not mounted.
When the drum heater is not mounted, it is essential to devise an image forming apparatus that does not form an oxide film due to durability from the beginning, and in particular, it is essential to devise a method of having the above function during the cleaning process. found.

Third, as described above, it has been newly discovered in our experiments that the frictional force between the transfer residual toner and the drum by the cleaning blade is increased due to the durability.

The oxide film layer (hereinafter referred to as a filming film) formed by the endurance increases the degree of adhesion and affinity between the cleaning blade and the drum surface, the residual toner and the drum surface, and increases the frictional force. I have.

It is considered that the increase in the frictional force increases the shear stress of the cleaning blade, the shear stress between toners, and the shear stress near the drum surface. As a result, chipping of the cleaning blade, occurrence of toner fusion due to an increase in heat generation due to an increase in permanent set shear stress,
It is considered that this leads to an increase in fatigue wear due to an increase in drum internal stress.

Fourth, in recent years, as described above, it has been widely used not only as a function of a copying machine but also as a printer. In addition, applications such as a feeder function and a sorter function have been enhanced, and it has become possible to continuously operate a job of 4000 sheets or more at a time. For example, in the case of 50 sheets / A4 machine, continuous operation is performed for 80 minutes or more even if a simple calculation is made. Under such circumstances, it is considered that the ambient temperature in the vicinity of the photoconductor has reached nearly 50 ° C., and the temperature at the contact (nip) between the cleaning blade and the photoconductor has reached a higher temperature. As a result, the frequency at which toner fusion occurs on the photosensitive member has increased.

Fifth, as described above, it is urgently necessary for us to reduce the main unit cost due to the problems of ecology and energy saving. Under such circumstances, it is necessary to reduce the cost of the photoreceptor, and it is becoming possible to form a film even if the thickness of an expensive high-purity aluminum cylinder is reduced as the material cost.

This is a direction in which the heat capacity of the photoconductor itself is reduced, and a direction in which the temperature unevenness in the axial direction of the photoconductor is increased.

In addition, as described above, since the planar heating element is disposed inside the photosensitive member for preventing image deletion, the temperature unevenness in the axial direction becomes more remarkable. As a result, the frequency at which toner fusion occurs on the photosensitive member has increased.

Sixth, the cleaning latitude is determined by the contact angle of the cleaning blade with the drum surface, free length, thickness, total pressure, linear pressure, rubber properties of the cleaning blade material, and the like. For example,
No. 6-274079 describes tan δ for eliminating chipping on the cleaning blade edge in a low-temperature and low-humidity environment (hereinafter referred to as “chipping”) and cleaning blade noise.
-13 ℃ ~ -16 ℃, high rebound resilience,
It is described that the Young's modulus is reduced. However, there is no description about the rebound resilience in a high temperature region and the surface pressure of the cleaning blade.

In our experiments, the rebound resilience of the rubber material of the cleaning blade, the contact width (nip width) of the cleaning blade with the drum, and the total pressure with respect to the nip width of the contact portion of the cleaning blade with the drum, ie, It has been found that the above-described filming film formation can be suppressed in consideration of the surface pressure (g / mm ² ). Further, the cause of the toner fusion generated on the drum is different from the organic photoconductor on the amorphous silicon photoconductor.
In the case of an organic photoreceptor, fine particles of an external additive such as silica are embedded in the surface of the photoreceptor to form a nucleus, thereby causing toner fusion. In this case, or even when there is no core, rain-like toner fusion occurs.

However, rubber materials generally have a large temperature dependence, and urethane rubber used as a cleaning blade is a rubber material having a particularly large temperature dependence.

The present invention has been made to address such a problem, and has been made to reduce local load unevenness acting between a cleaning blade, a photosensitive drum, and residual toner after transfer.
It is an object of the present invention to provide an electrophotographic apparatus having a significantly improved reliability and a cleaning apparatus capable of responding to a breakthrough in productivity of the electrophotographic apparatus.

[0024]

The above object of the present invention is achieved by the following image forming apparatus.

(1) An image forming unit for forming a toner image on an image carrier, an image transfer unit for transferring the toner image on the image carrier to a transfer material, and transfer to the transfer material by the image transfer unit An image forming apparatus including a cleaning unit that removes transfer residual toner on the image carrier after the
The image carrier is an amorphous silicon-based photoreceptor, and the cleaning unit is an elastic blade, and the resilient material of the elastic blade has a rebound resilience at a temperature in the range of 5 ° C to 60 ° C, and An image forming apparatus wherein the physical properties of the elastic blade are 45% or less at 45 ° C. in a region showing a rubber state, and the temperature dependence of the rebound resilience is from -1% / deg to + 1% / deg. (2) The thickness of the conductive substrate of the image carrier is 3.0 mm or less.
(3) The toner has an average particle diameter of 6 μm to 8 μm, and a glass transition temperature of 40 ° C. to 6 ° C.
(1) The image forming apparatus according to (1), which has at least 0.2 to 20 parts by weight of a solid wax and 10 to 200 parts by weight of a magnetic powder carrying a liquid lubricant with respect to 100 parts by weight of a binder resin having a temperature of 0 ° C. (4) The image forming apparatus according to (1), wherein the height of the surface abnormal growth projection portion of the image carrier is polished to 5.0 μm or less before use.
(5) The image forming apparatus according to (1), wherein a contact width (nip width) of the cleaning blade with respect to the drum surface is 10 μm or more and 60 μm or less, and (6) a surface pressure of the cleaning blade with respect to the drum surface is: 100
The image forming apparatus according to g / mm ² or more 400 g / mm ² or less (1).

According to the present invention, as a cleaning blade material, the rebound resilience at 45 ° C. is 45% or less, and the temperature dependence of the rebound resilience is -1% / deg to + 1% / deg. By using such a material, it is possible to improve the reliability of toner fusion.

To explain the above, the cause of the toner fusion generated on the drum is different from the organic photoconductor on the amorphous silicon photoconductor. In the case of an organic photoreceptor, fine particles of an external additive such as silica are embedded in the surface of the photoreceptor and serve as a nucleus, causing toner fusion. Or, even if there is no core to be formed, rain-like toner fusion occurs. It has been found that the former fusion does not occur even if the toner has an average particle diameter of 6 μm and the protrusion is 5 μm or less. It was found that the latter fusion had a correlation with the rebound resilience of the blade material. Normal measurement temperature 2
The resilience at around 3 ° C. is different from the resilience under the conditions of use on the actual machine. The present inventors have conducted intensive studies and found that if the temperature dependence of the rebound resilience is reduced, toner fusion can be prevented from occurring due to fluctuations in ambient temperature, temperature rise due to continuous paper passing, and the like. .

FIG. 6 shows the range of the temperature and the rebound resilience for the occurrence of fusion. In FIG. 6, since the rebound resilience (%) of the member 1 is higher than the lower limit at which fusion occurs at any temperature (° C.), fusion occurs. Member 3
Although no fusion occurs at about 25 ° C., fusion occurs in a high temperature region because the rate of change in rebound resilience (%) is large relative to the rate of change in temperature (° C.). The cleaning blade rubber material becomes highly elastic as the temperature rises. When cleaning the transfer residual toner, the blade rubber material becomes highly elastic due to a rise in temperature, and if there is a transfer residual toner locally, a load fluctuation occurs and the blade edge is easily separated from the transfer residual toner. As a result, it is considered that toner which is not cleaned by the cleaning blade edge momentarily becomes a nucleus and toner fusion occurs. For this reason, it is considered that toner fusion occurs when the rebound resilience is high.

Further, according to the present invention, even if the total pressure is increased, the surface pressure does not increase only by increasing the nip width. In this case, if the thickness exceeds 60 μm, the filming film is laminated from an early stage. As a result, the edge of the cleaning blade does not surely hit the photoconductor, but the cleaning blade is touched. That is, it is considered that the pressure distribution on the photoconductor becomes broad. Conversely, if the nip width is less than 10 μm, the component configuration tolerance becomes severe, making it impossible to partially form the nip, resulting in poor cleaning. If the nip width is 10 μm to 60 μm, it is possible to prevent the filming film from causing an image defect.

Further, by increasing the surface pressure (g / mm ² ) against the drum surface of the cleaning blade, it is possible to suppress the formation of a filming film. Specifically, the above effect is clearly exerted at 100 g / mm ² or more, and at 400 g / mm ² or more, the shear stress of the blade material becomes too large and breaks. In addition, the strength of the holding member is limited, and the operation of the device itself becomes impossible.

In the present invention, the thickness of the aluminum cylinder constituting the photosensitive drum is preferably 3 mm or less, and 1.0 mm or more in view of mechanical strength. This reduces the heat capacity of the photoconductor itself.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. (Prescription of photoreceptor used in the present invention) After a blocking layer and a photoconductive layer were laminated on a cylindrical conductive substrate under the conditions shown in Table 1 using a plasma CVD apparatus, the surface layer under the conditions shown in Table 2 was added to 0.1 mm. 6μ
Thus, a light receiving member was manufactured.

FIG. 4 is a schematic sectional view showing the layer structure of the photosensitive drum (light receiving member) used in the present invention. The a-Si based light receiving member shown in FIG. 4 has a photoconductive layer 403 made of an amorphous material containing at least silicon atoms stacked on a conductive substrate 401 such as aluminum, and further has carbon atoms and hydrogen atoms. This is a light receiving member having a photosensitive layer 402 in which a surface layer 404 composed of an aC: H film or an a-SiC: H film is sequentially laminated.

The deposition of the light-receiving member by the plasma CVD method is performed by a known method. In particular, it is necessary to supply a high-frequency power having a frequency of 1 MHz to 450 MHz as a high-frequency power supply to generate a high-frequency glow discharge, and to clean the surface layer. It is preferable for improving performance.

[0035]

Table 1 Production Conditions lower blocking layer of the light-receiving member _{‥‥‥ SiH 4 300scc H 2 500scc NO} 8scc B 2 H 6 2000ppm power 100 w (13.56 MHz) pressure 53.2 Pa (0.4 torr) thickness 1μm photoconductive Layer ‥‥‥‥ SiH ₄ 500 scc H ₂ 500 scc Power 400 w (13.56 MHz) Internal pressure 26.6 Pa (0.5 torr) Film thickness 25 μm

[0036]

Table 2 Manufacturing conditions for surface layer of Example 3 SiH ₄ / CH _{4 10} CC / 500 CC Power 150 w (13.56 MHz) Internal pressure 39.9 Pa (0.3 torr) Substrate temperature 250 ° C.

[0037]

Embodiments of the present invention will be described below with reference to the accompanying drawings. First Embodiment First, an outline of a configuration of an electrophotographic copying machine will be described with reference to FIGS. 1 and 2 as an example of an image forming apparatus according to the present invention.

FIG. 1 is a schematic sectional view showing the basic structure of an electrophotographic apparatus according to the present invention. In FIG. 1, reference numeral 1 denotes an amorphous silicon photosensitive drum which is an image carrier which is driven to rotate at a predetermined speed in a direction indicated by an arrow R1. Around the photosensitive drum 1, a pre-exposure device 2, a primary charger 3, an image exposure device 4, a developing device 5, a transfer separation charger 7, a cleaning device 9
Are arranged respectively. The cleaning blade 9a is made of urethane rubber having a thickness of 2 mm.

The primary charger 3 and the developing sleeve 5
A high-voltage power supply and the like (not shown) are connected to a and the transfer separation charger 7. Further, the photosensitive drum 1, the developing sleeve 5a
Are independently driven to rotate by drive motors (not shown).

Next, an image forming operation in the present electrophotographic copying machine will be described. The photosensitive drum 1 is driven to rotate at a predetermined speed in the direction of the arrow shown in the figure, and after the surface is eliminated by the pre-exposure device 2, the surface is uniformly charged by the primary charger 3. When the surface of the photosensitive drum 1 is irradiated with image exposure 4 (laser light peak wavelength: 653 nm), an electrostatic latent image corresponding to the image is formed on the surface of the photosensitive drum 1, and the electrostatic latent image is The toner image is developed by the developing device 5 and visualized as a toner image.

On the other hand, the transfer material P is fed to a registration roller 10 by a transport system (not shown), and the transfer material P is transferred by the registration roller 10 at an appropriate timing to a transfer nip between the photosensitive drum 1 and the transfer separation charger 7. After the toner image is transferred to the photosensitive drum 1 and transferred to the photosensitive drum 1, the toner image is separated from the photosensitive drum 1 by the operation of the transfer / separation charger 7.

Then, the transfer material P separated from the photosensitive drum 1 is sent to the fixing device 12 by the transport device 11 and fixes the transfer material P on which the toner image is placed.

The maximum image width of the electrophotographic copying machine according to this embodiment is about 290 mm on the side of A4, and the peripheral speed of the drum is 300 mm / sec.

The photosensitive drum 1 has a diameter of 80 mm.
An amorphous silicon photosensitive layer having a thickness of 30 μm is formed by glow discharge or the like on an aluminum cylinder having a thickness of about 3 mm and a thickness of about 3 mm. As the surface layer of the photosensitive drum, a layer obtained by laminating 8000 A of SiC: H was used.

The developing device 5 has a developing sleeve 5a formed by forming a coating layer in which phenol resin, graphite, and carbon are mixed on the surface of an aluminum cylinder having a diameter of 20 mm, and has a toner t as a developer therein. Is housed.

The developing sleeve 5a is driven at a relative speed of 150% in a direction opposite to that of the photosensitive drum 1, and a gap between the developing sleeve 5a and the photosensitive drum 1 is set to 230 μm. A magnetic blade is used to coat the toner t on the developing sleeve 5a, a gap between the developing sleeve 5a and the magnetic blade is set to 280 μm, and a frequency of 2700 Hz and a peak-to-peak voltage of 1400 are used as a developing bias.
v, a rectangular wave having a duty ratio of 35% and a direct current are applied to the developing sleeve 5a.

Further, the cleaning blade 9 that is in contact with the surface of the photosensitive drum 1 is held in the cleaning container 9b of the cleaning device 9.

FIG. 2 is a schematic sectional view of a cleaner device of the electrophotographic apparatus of the present invention.
Hardness of 70 ° (H
s), rebound resilience 15 (%) (rebound resilience at 40 ° C. 2)
5%), 300% modulus 200 (kg / cm ² )
(Both in accordance with JIS standards) with a contact angle of 24
°, a contact pressure of 10 (g / cm), and a surface pressure of 150 g / mm ² . Cleaning blade 9a
Has a plate thickness of 2 mm and a member 9c (SUS plate thickness of 1.0 m
m) is provided as a back plate. The free length of the cleaning blade is 3 mm. On the upstream side of the cleaning blade 9a (upstream in the rotation direction of the photosensitive drum 1) in the cleaner container 24, a magnet roller 22 that is long in a direction perpendicular to the paper surface of FIG. It is provided. A separation claw 29 is provided upstream of the pre-cleaner exposure. Mag Roller 2
2 is a relative speed of 10 in the forward direction with respect to the rotation direction of the photoconductor 1.
% At the peripheral speed. As the pre-exposure device 2, 6
Using a light emitting diode (element GaAlAs) mainly having a peak wavelength of 60 nm, the half width at which the peak wavelength is １ ／ is about 25 nm, and the exposure amount is 20 μJ / cm.
² About 50 from the pre-exposure device 2 to the primary charger 3
mm / sec. The mag roller 5 rotates at a peripheral speed of 10% relative speed in the forward direction with respect to the rotation direction of the photoconductor 1. The mag roller 22 is 1.0 mm
Are arranged with a gap. The regulating roller 23 is provided with a gap of 1.8 mm from the mag roller 22, and rotates in the forward direction at a relative speed of 10% with respect to the mag roller 22.

As the toner t, an octahedral average particle diameter of 0.18 μm was used as the magnetic powder. The average particle size of positively charged is about 6.5 μm, and the main binder is styrene- (meth)
A one-component magnetic toner having a glass transition point of about 60 ° C. using about 100 parts by weight of an acrylate copolymer and a magnetic substance, and 0.5 parts by weight of an inorganic powder of silica as an external additive is used. The charge amount on the developing sleeve 5a is +3 to +12
(ΜC / g), coating amount: 0.6 to 1.3 mg / cm ²
It is. The photoreceptor 1 used was one whose surface was polished to a Rmax of 5 μm or less as described in JP-A-07-010488.

In the present invention, no problem such as chipping occurred at the edge of the cleaning blade even after the endurance of one million sheets. Even after the endurance of 3 million sheets of the photoreceptor 1, there were no problems such as fusion, partial filming, and scratches on the image. Example 2 The configuration was the same as that of Example 1, except that only the cleaning blade material was changed. The cleaning blade is an elastic blade mainly composed of urethane and has a hardness of 77 ° (Hs) and a rebound resilience of 1
0 (%) (25 ° C.) (20% rebound resilience at 40 ° C.)
With a 300% modulus of 250 (kg / cm ² ) (all according to JIS standards), a contact angle of 28 ° and a contact pressure of 2
0 (g / cm) and a surface pressure of 200 g / mm ² . Even after the endurance of 3 million sheets of the photoreceptor 1, there were no problems such as fusion, partial filming film generation, defective cleaning, scratches and the like, which occur in the image. Third Embodiment The configuration of the present embodiment is almost the same as that of the first embodiment, and only changed portions will be described with reference to FIG. The cleaning blade material of the cleaning blade 30 is the same as that of the first embodiment. The cleaning blade 30 is obtained by integrally molding the rubber material of Example 1 on a sheet metal having a thickness of 1.0 ton of phosphor bronze. Contact angle 24 °, contact pressure 20 (g / cm), contact pressure 150 (g)
/ Cm ² ). 3 photoconductors
Even after the endurance of 100,000 sheets, no problems such as fusion, partial filming film generation, poor cleaning, scratches and the like, which occur in images, occurred. Comparative Example 1 The same configuration as in Example 1 was used except that only the cleaning blade material was changed. The cleaning blade is an elastic blade mainly composed of urethane and has a hardness of 73 ° (Hs) and a rebound resilience of 3
5 (%) (25 ° C.) (rebound resilience at 40 ° C. 67%),
300% modulus 150 (kg / cm ² ) (all according to JIS standard), contact angle 24 °, contact pressure 1
0 (g / cm) and a surface pressure of 150 g / mm ² are provided on the photoreceptor 1. After about 50,000 prints, fusing occurred. After that, the length of the fusion became longer and the number increased. Comparative Example 2 The basic configuration was the same as that of Example 2 except that a photosensitive member 1 having a projection of 8 μm was used. After passing about 30,000 sheets, fusion occurred on the protruding portion, and after passing 500,000 sheets, poor cleaning occurred from the protruding portion. Comparative Example 3 The basic configuration is the same as in Example 1. The point of change was that the surface pressure was set to 50 (g / cm ² ), and a photoreceptor having a projection of 10 μm was used.

After passing 20,000 sheets, fusion of the protrusions occurred, and after passing 500,000 sheets, poor cleaning occurred from the protrusions.
After 1 million sheets were passed, the film thickness was measured with a reflection spectroscopic interferometer (MCDP2000 manufactured by Otsuka Electronics Co., Ltd.), and a filming layer of 80 ° was confirmed.

Table 3 shows the results of Examples and Comparative Examples. The indications in Table 3 are as follows.

Fusion: ○ indicates no fusion and X indicates fusion.

Projection fusion: ○ indicates no fusion of the projection, and X indicates fusion of the projection.

Filming film: ○ indicates no occurrence of filming film, and X indicates occurrence of filming film.

Cleaning: は indicates good cleaning,
X indicates poor cleaning.

[0057]

[Table 3]

[0058]

According to the present invention, a cleaning blade,
Reduces local load unevenness that acts between the photosensitive drum and transfer residual toner, greatly improves the reliability of electrophotographic equipment, and can respond to the breakthrough in productivity of electrophotographic equipment. It has become possible to provide an electrophotographic apparatus having a cleaning device.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a basic configuration of an electrophotographic apparatus according to the present invention.

FIG. 2 is a schematic sectional view of a cleaning device of the electrophotographic apparatus of the present invention.

FIG. 3 is a schematic sectional view of a cleaning device according to a third embodiment of the present invention.

FIG. 4 is a schematic sectional view showing a layer configuration of a photosensitive drum used in the present invention.

FIG. 5 is a diagram illustrating a place where transfer residual toner stays near a cleaning blade edge according to the present invention.

FIG. 6 is a diagram showing a region where the temperature and the rebound resilience of the present invention are generated with respect to drum fusion.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photosensitive drum 2 pre-exposure device 3 primary charger 4 image exposure device 5 developing device 5 a developing sleeve 7 transfer separation charger 9 cleaning device 9 a cleaning blade 9 b cleaning container 9 c SUS1.0 t cleaning blade back plate 10 resist roller pair 11 transport unit REFERENCE SIGNS LIST 12 Fixing device 20 Cleaning device of Example 3 22 Mag roller 23 Restriction roller 24 Cleaner container 25 Pressure spring 26 Cleaner blade equalizing member 30 Cleaning blade of Example 3 401 Conductive substrate 402 Photosensitive layer 403 Photoconductive layer 404 Surface layer

Claims (6)

[Claims] An image forming unit for forming a toner image on an image carrier, an image transfer unit for transferring the toner image on the image carrier to a transfer material, and an image transfer unit transferring the toner image to the transfer material by the image transfer unit. In an image forming apparatus provided with a cleaning unit that removes transfer residual toner on the image carrier after the image carrier is an amorphous silicon-based photoconductor, and the cleaning unit is an elastic blade, The rebound resilience of the elastic material of the resilient blade is 45% or less at 45 ° C. in a region where the temperature is in the range of 5 ° C. to 60 ° C. and the physical properties of the resilient blade show a rubbery state. An image forming apparatus, wherein the temperature dependency is from -1% / deg to + 1% / deg. 2. The thickness of the conductive substrate of the image carrier is:
The image forming apparatus according to claim 1, wherein the size is 3.0 mm or less. 3. The toner has an average particle diameter of 6 μm to 8 μm.
And 0.2 to 2 solid waxes per 100 parts by weight of binder resin having a glass transition temperature of 40 ° C to 60 ° C.
The image forming apparatus according to claim 1, wherein the image forming apparatus has at least 0 parts by weight and 10 to 200 parts by weight of magnetic powder. 4. The image forming apparatus according to claim 1, wherein the height of the surface abnormal growth projection portion of the image carrier is polished to 5.0 μm or less before use. 5. A contact width (nip width) of the cleaning blade to a drum surface is 10 μm or more and 60 μm or more.
The image forming apparatus according to claim 1, wherein: 6. A surface pressure of the cleaning blade against a drum surface is 100 g / mm ² or more and 400 g / mm ² or more.
^2. The image forming apparatus according to claim 1, wherein the number is ² or less.