JP2001142371A - Electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic device capable of stably and excellently forming an image by excellently cleaning the surface of a photoreceptor drum for a long period even in the case of using toner having additive and using the photoreceptor drum whose dynamic hardness is large without shortening the lives of the photoreceptor drum and a cleaning blade. SOLUTION: As for this electrophotographic device, the edge of a part where the cleaning blade consisting of a belt-like elastic body for removing residue on the surface of the photoreceptor abuts on the photoreceptor is made rough. The device is adjusted so that Ry is within >=2.0 μm and <=15.0 μm and Sm is within >=5.0 μm and <=25.0 μm on a condition that reference length is 0.08 mm and evaluation length is 0.4 mm, and constituted so that the additive in the toner can selectively slip through from the cleaning blade and the surface of the photoreceptor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for charging a surface of a photoreceptor, which is an image bearing member, and writing image information on the charged surface with visible light, line scanning laser light or the like to form an electrostatic latent image. The present invention relates to an electrophotographic apparatus for forming an image, further developing the latent image to form a toner image, and then transferring the toner image to a transfer material to form an image. The present invention relates to an electrophotographic apparatus having means.

[0002]

2. Description of the Related Art Conventionally, for cleaning a photosensitive drum, a belt made of a band-like elastic material such as urethane rubber is often used. Such a cleaning blade is excellent in elasticity, but has a large surface frictional resistance. Therefore, the cleaning blade is dragged in the rotation direction of the photosensitive drum depending on the correlation between the pressure force applied to the photosensitive drum and the frictional force applied to the photosensitive drum. As a result, a so-called "turn-up" in which the tip of the cleaning blade bends in the rotation direction of the photosensitive drum may occur, and a phenomenon may occur in which normal cleaning cannot be performed. Further, since the portion of the cleaning blade in contact with the photosensitive drum is precision cut so as to guarantee the accuracy of the order of microns or less, the frictional force with the photosensitive drum tends to increase more and more.

[0003] In order to solve the above-mentioned problems, conventionally, it has been practiced to attach a highly lubricious substance such as a fluororesin-based powder to the tip of a cleaning blade to reduce friction (particularly). JP-A-3-107983, 3-
No. 1,079,843, and No. 3,107,987).

[0004] As another method, a cleaning blade 30 having a cleaning structure as shown in FIG.
A method has been proposed in which the toner is re-applied to the photosensitive drum to function as a lubricant on the front side of Step 2, thereby reducing the frictional force between the cleaning blade and the photosensitive drum.

However, it is difficult to apply the fine powder (toner) as a lubricant in the longitudinal direction of the photoreceptor, and it is difficult to uniformly apply the fine powder in the longitudinal direction of the photoreceptor. Therefore, cleaning may not be performed in some cases. In recent years, toners using external additives as surface modifiers for toner particles have been widely used. External additives are originally used to improve the fluidity of the toner. However, in addition to this, the image quality for imparting various functions to the toner, such as improving image density, reducing background fog, and improving resolution, etc. May be used as an enhancer. Examples of the external additive material include fine powder (having a primary particle size of about 10 to 50 nm) such as colloidal silica, titanium oxide, and alumina, which are used for removing residual toner from the photoreceptor surface. Has an effect of reducing friction between the cleaning blade and the photosensitive drum. However, since the external additive material as described above has a very high hardness, when the external additive interposed between the cleaning blade and the surface of the photoreceptor slips through the photosensitive drum or the cleaning member, In some cases, the blade is damaged, and the life of the photosensitive drum or the cleaning blade is shortened.

In an electrophotographic apparatus having a high copy (or print) speed, it is necessary to increase the peripheral speed of the photosensitive drum. In this case, however, the wear amount of the photosensitive drum increases, or the cleaning blade increases. This leads to increased wear, which is a problem in achieving high durability. Therefore, in order to improve the life of the photoconductor, a photoconductor using a-Si may be used as a photoconductor having a high surface hardness. On the outermost surface of the photoreceptor whose main body is a-Si, aC or a-SiC is used as a surface protective layer. Since these materials are very hard compared to urethane rubber and other materials used for the cleaning blade, the damage to the cleaning blade is increased, and even if the life of the photosensitive member can be extended, the entire apparatus can be achieved. Could not extend the lifespan. Another problem caused by friction between the cleaning blade and the photosensitive drum is so-called "toner fusion" in which the toner is melted and adhered to the photosensitive drum by frictional heat generated by the friction and the pressing force of the cleaning blade. That phenomenon may occur. For such issues,
Conventionally, the contact pressure of the cleaning blade is increased, and even if "toner fusion" occurs, it can be scraped off,
A method of using a hard blade whose elasticity of the blade is reduced by changing a crosslinking condition of a resin material forming the blade has been used.

[0007]

However, any of these methods has a problem that the load on the cleaning blade is increased. For example, when the blade pressure is increased, the durability of the blade may be impaired, or the surface of the photosensitive drum may be excessively shaved.
In addition, in the method of hardening the cleaning blade material, the blade is easily chipped. For example, the edge portion is damaged even by a projection of several microns adhering on the photosensitive drum, and the cleaning failure is caused. Cause. Accordingly, an object of the present invention is to provide an electrophotographic apparatus having a cleaning means for cleaning the surface of a photoreceptor, without reducing the life of a photoreceptor drum or a cleaning blade, and further comprising a fine powder of colloidal silica, titanium oxide, alumina or the like. It is an object of the present invention to provide an electrophotographic apparatus which can clean the surface of a photoreceptor satisfactorily even if a toner using the toner as an external additive is used.

[0008]

The above objects are achieved by the present invention described below. That is, the present invention provides a charging means for charging an electrophotographic photosensitive member, a latent image forming means for exposing the charged electrophotographic photosensitive member to form a latent image, and developing the latent image with toner to form a toner image. Developing means, a transferring means for transferring the toner image to a transfer material, and a cleaning means for removing residues and / or foreign matters on the surface of the electrophotographic photosensitive member by a cleaning blade, and the electrons cleaned by the cleaning means. In an electrophotographic apparatus that repeatedly performs image formation using a photographic photosensitive member, the toner has at least toner particles and an external additive, and the cleaning blade is a blade made of a band-shaped elastic body, and the photosensitive member of the cleaning blade and have an edge abutting portion is roughened, the reference length 0.08 mm, rated in length 0.4 mm, the maximum height R _y is, .0μm
The cleaning blade is adjusted so as to be within the range of not less than 15.0 μm and the average interval Sm of the unevenness within the range of not less than 5.0 μm and not more than 25.0 μm. And an electrophotographic apparatus configured to be able to pass through the surface of the photoconductor. Note that R _y and Sm are 1999
It is a value measured by the method described in JIS Handbook 34 JIS B0601.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail by way of preferred embodiments of the present invention. The present inventors have conducted intensive studies in order to solve the problems of the prior art regarding the above-described electrophotographic apparatus, particularly, a means for cleaning the residual toner on the photoconductor after the transfer of the toner image, and as a result, a portion of the electrophotographic apparatus in contact with the photoconductor drum has been developed. Focusing on the shape of the edge of the cleaning blade, the present inventors have found that if the edge portion is roughened to have a specific shape, the above-described problem of the related art can be solved, and the present invention has been made. 1 (b) and (c),
Although an example of the specific shape of the edge portion of the cleaning blade used in the electrophotographic apparatus of the present invention has been described, specifically, the edge of the portion of the cleaning blade made of a band-shaped elastic body that comes into contact with the photoconductor is roughened. When the edge portion has a reference length of 0.08 mm and an evaluation length of 0.4 mm, R _y
Is within the range of 2.0 μm to 15.0 μm, and the value of Sm is within the range of 5.0 μm to 25.0 μm.

With such a specific shape, the frictional force between the photosensitive member and the cleaning blade can be reduced without reducing the contact pressure of the cleaning blade. Good cleaning of the surface of the photoreceptor can be performed without reducing the life of the body drum and the cleaning blade, and even when a toner using fine powder such as colloidal silica, titanium oxide, and alumina as an external additive is used. It becomes possible.

Further, according to the above configuration, since the external additive of the toner easily leaks from the contact portion of the cleaning blade, the external additive may be exposed when the external additive passes between the cleaning blade and the photosensitive member. Damage to the body drum or the cleaning blade is prevented, and an electrophotographic apparatus having stable cleaning performance for a long time can be provided.

The electrophotographic apparatus of the present invention having the above-described cleaning means having excellent effects will be described below for each component. "Image Forming Apparatus" FIG. 4 is a schematic view of an image forming process in a copying machine as an example of the electrophotographic apparatus of the present invention. A main charger 10 is provided around an electrophotographic photosensitive member (hereinafter, simply referred to as a “photosensitive member”) 101 which rotates in the direction of arrow X in FIG.
2. Electrostatic latent image forming portion 103, developing device 104, transfer paper supply system 105, transfer charger 106 (a), separation charger 10
6 (b), cleaner 107, transport system 108, static elimination light source 1
09 etc. are provided. The temperature of the photoconductor 101 may be controlled by a planar inner surface heater 125 as necessary.

The image forming process will be described in order. First, the surface of the photosensitive member 101, which is uniformly charged by the main charger 102, is exposed by the image exposure applying means 103, and the electrostatic latent image is formed on the photosensitive member 101. An image is formed.
The electrostatic latent image is formed by a developing device 104 for carrying a developer having toner on the surface thereof and transporting the toner to a developing area.
Is visualized as a toner image by the developing sleeve. Next, this toner image is transferred onto the transfer material P supplied through the transfer paper supply system 105. The transfer material P to which the toner image has been transferred is supplied to the separation charger 106 (b) and / or
Alternatively, the photosensitive member 101 is separated from the photosensitive member 101 by a separating means such as a nail. The separated transfer material P is sent to the fixing device 123 after passing through the transport system 108, and after the toner image on the surface is fixed by the fixing roller 124 in the fixing device 123, the transfer material P is transferred to the outside of the image forming apparatus. Is discharged.

After the toner image has been transferred to the transfer material P as described above, foreign matters such as transfer residual toner and paper dust adhere to the surface of the photoreceptor 101. Photosensitive member 1 by cleaning blade 120, cleaning roller (or brush) 121, etc.
01 is removed from the surface. Photoconductor 1 that has been cleaned
01 is used for the next image formation. As described above, in a well-known image forming apparatus that repeats a process of transferring a transferable toner image onto the photoconductor surface onto a transfer material P such as paper, cleaning the toner and foreign matters remaining on the photoconductor surface after the transfer. It must be removed by means. Therefore, as this type of cleaning device, a cleaning blade made of rubber, an elastic resin, or the like, a cleaning brush made of synthetic resin fibers, or the like has been practically used. In addition,
There is also a method of adsorbing and removing magnetic powder such as toner remaining on the photoreceptor surface by magnetism.

An outline of an example of these cleaning devices and means will be described in more detail with reference to the drawings. "Cleaning Device" FIG. 3 is a diagram showing an example of the cleaning device 107 of the copying machine shown in FIG. 4 in detail.
In the cleaning means, a cleaning blade 302 made of urethane rubber or the like, a cleaning roller 303 made of a material such as silicon rubber or sponge, or a magnetic material, a doctor roller 304, It comprises a waste toner reservoir 305, a waste toner transport system 306, and the like. The doctor roller 304 shown in FIG. 4 is installed as needed, and may be in the form of a blade. In this case, it is called a scraper (or doctor blade). Hereinafter, in the description of each member of the cleaning device, description of the scraper will be omitted for simplification.

In the cleaning device 301, a cleaning blade 302 having appropriate elasticity and hardness by, for example, mixing urethane rubber with a silicon compound is installed. A cleaning roller 303 composed of a magnet, a sponge, a brush, or the like is provided upstream of the cleaning blade 302 in the rotation direction of the photoconductor 101. The cleaning roller 303 has a function of collecting the untransferred toner, re-applying it on the photoconductor, and sending excess toner to the waste toner reservoir 305. The recoating on the photoreceptor is performed by a magnetic force, an adhesive force, or an electric field. The coated portion of the magnetic powder attached to the cleaning roller 303 abuts on the surface of the photoconductor 101 with an appropriate abutment width (nip width), and rubs with the photoconductor at a predetermined relative speed.

As a cleaning material used for a high-hardness photoreceptor such as an a-Si type photoreceptor, a chemical fiber brush such as polyethylene or polystyrene or the like, which has appropriate conductivity by mixing carbon into the chemical fiber. A brush made of such conductive fibers and amorphous metal fibers (eg, unitika bolfa) may be used. The nip width between the photosensitive member 101 and a cleaning roller or a cleaning brush is set to a predetermined value in order to keep the cleaning property constant or to prevent a problem such as abrasion of the photosensitive member due to a local excessive contact pressure or the like. It is preferable that the width is held within the range.

As a mechanism for holding the nip width of the cleaning roller or the cleaning brush, a roller or the like may be pressed against an appropriate position outside the image area, or the cleaning roller 303 may be pressed against the photosensitive member with a predetermined pressure. .
In the case of a magnetic roller or the like, a method of adjusting the toner coat thickness is also possible. In addition, as the cleaning device used in the present invention, a cleaning device in which a part of the above-described configuration is removed or in which a configuration is further added may be used.

FIG. 2 is a diagram for explaining each operation in the repetition of the cleaning means using the above-described cleaning device. Hereinafter, the outline of the cleaning unit will be described step by step with reference to FIG. <Step 1. > The photoconductor 101 with which the cleaning device 301 is in contact rotates at a predetermined speed. In FIG. 2, the surface of the photoconductor 101 moves from the left side of the paper to the right side where the cleaning blade 302 is located. As described with reference to FIG. 4, a toner image is formed on the surface of the photoconductor by the charging unit, the latent image forming unit, and the developing unit. After that, the toner image is transferred to the transfer material, but so-called residual toner, foreign matter such as rosin and talc, which cannot be transferred by the transfer member, is subjected to electrostatic force (Coulomb force), intermolecular force, and frictional force. The cleaning device approaches the cleaning device in a state of the adhering matter adhering to the surface of the photoreceptor due to other adhesive force or the like.

Here, the photoreceptor 101 may be maintained at a predetermined temperature as required. Further, as described above, the cleaning roller 303 (or cleaning brush or the like: hereinafter, the description in parentheses is omitted) is provided as needed, and may not be provided. The cleaning blade 302 includes the photosensitive member 101.
In many cases, it is used in a state where powder is applied in order to impart lubricity to the photoreceptor at a contact portion with the surface.
In FIG. 2, a part of the waste toner already collected or the toner applied to the cleaning roller by an appropriate method is appropriately supplied from the cleaning roller 303 via the toner reservoir 307.

<Step 2. > In a system having the cleaning roller 303, the above-described residual toner and the like are rubbed and scraped by the cleaning roller 303, or
Collected by suction. These toners are taken into the cleaning roller 303.

<Step 3. The captured residual toner and the like are partially collected by an appropriate mechanism such as a doctor roller (or doctor blade: hereinafter, the description in parentheses is omitted) 304 or the like. Then, the collected residual toner and the like are sent to the toner reservoir 305 in the cleaning device 301. As described above, the cleaning blade 302
From the viewpoint of improving the lubricity with the photoconductor, the cleaning roller 303 may release an appropriate amount of residual toner or the like. The collected toner is further collected in a waste toner collection container (not shown) via the waste toner transport system 306 and the like (see FIG. 3). Alternatively, some or most of the toner may be sorted and reused for image formation.

<Step 4. > The residual toner not collected by the cleaning roller 303, the residual toner of a system having no cleaning blade 303, the residual toner released from the cleaning roller as described above, and the like adhere to the surface of the photoconductor 101. It approaches the cleaning blade 302 in the state. These residual toners and the like are scraped off and collected by the cleaning blade 301 of the cleaning device 301, for example. The collected toner is conveyed from a waste toner reservoir 305 to a waste toner storage unit (not shown) via a waste toner conveyance system 306 including a screw and the like, and discharged. This waste toner reservoir may be installed in a portion (not shown) of the image forming apparatus, or may be incorporated in a cleaning device in an image forming apparatus such as a cartridge type laser beam printer. The electrostatic latent image remaining on the surface of the photoreceptor is erased by an unillustrated static elimination light source 109 outside the cleaning device.

In addition to the above-described cleaning roller 304, as described above, a means for removing a variety of adhered foreign substances by rubbing the surface of the photoreceptor with a brush-like cleaning brush may be used. In addition, a magnetic cleaning roller made of a magnetic material, a cleaning roller in which a bias is applied to a polarity opposite to that of the toner, or a cleaning roller itself configured to have a polarity opposite to that of the toner is used in a non-contact manner, or Contact the photoreceptor surface,
Alternatively, a method of indirectly pressing and rubbing the photoreceptor with suctioned collected toner or the like to remove extraneous matter has been proposed, but any of them can be used in the present invention. These devices (cleaning blades, cleaning brushes, cleaning rollers, etc.) are arranged in the cleaning device, and are used alone or in combination to remove the above-mentioned powder such as foreign matter and residual toner from the photoreceptor surface. Remove the body.

The electrophotographic apparatus of the present invention has a cleaning means for removing the toner residue and / or foreign matter on the surface of the electrophotographic photosensitive member by the cleaning blade as described above, and the cleaning blade has a belt-like elasticity. The cleaning blade is characterized in that the edge of the cleaning blade in contact with the photoreceptor is roughened and the edge has a specific shape. The operation of the electrophotographic photosensitive member and the cleaning means used in the electrophotographic apparatus of the present invention will be specifically described. The present invention is not limited to these experimental examples.

Experimental Example 1 First, an electrophotographic photosensitive member used in the electrophotographic apparatus of the present invention will be described. The photoconductor has a dynamic hardness at the outermost surface thereof (dynamic hardness when using a triangular pyramid diamond stylus with a ridge angle of 115 ° having a radius of 0.1 μm or less at the tip) within a range of 300 to 1,000. It is preferred to use some. As such, it has a light receiving portion layer and a surface protective layer, the light receiving portion layer contains at least amorphous silicon, and the surface protective layer contains amorphous silicon carbide or amorphous carbon. Is preferably used. For example, it is preferable to use a photoreceptor having a-Si as a mother body provided with a film such as aC or a-SiC as a surface protective layer on the outermost surface. In particular, in an electrophotographic apparatus having a high copy (or print) speed, it is necessary to increase the peripheral speed of the photosensitive drum. Therefore, it is preferable to use a material made of such a material having excellent durability.

FIG. 7 shows a film forming apparatus used for producing the photoreceptor used in the present invention. If such an apparatus is used, a-SiC: H or aC: H Can be easily formed. As a method for forming these surface layers, once the inside of the reaction vessel 701 is evacuated to a high vacuum, a predetermined raw material gas, for example, silicon hydride such as SiH ₄ , CH ₄ , C ₄
After mixing hydrocarbon gases such as ₂ H ₆ , C ₃ H ₈ and C ₄ H ₁₀ and, if necessary, material gases such as hydrogen gas, helium gas and argon gas by a mixing panel (not shown), the reaction vessel 701 Introduce within.

Next, each raw material gas is adjusted to a predetermined flow rate by a mass flow controller (not shown). At this time, the opening of the main valve 704 is adjusted while watching the vacuum gauge 710 so that the inside of the reaction vessel 701 has a predetermined pressure of 1 Torr or less. After confirming that the internal pressure has stabilized, the high-frequency power source 712 is set to a desired power, and the power is supplied to the cathode electrode 706 to generate a high-frequency glow discharge. At this time, the valve 709 is adjusted so that the reflected wave is minimized. The value obtained by subtracting the reflected power from the high-frequency incident power is adjusted to a desired value.

As a result, each source gas introduced into the reaction vessel 701 is decomposed by the discharge energy, and a predetermined a-SiC: H is formed on the photoconductive layer of the cylindrical substrate 702.
Alternatively, an aC: H deposited film is formed. After the desired film thickness is formed, the supply of high-frequency power is stopped, and the reaction vessel 70
1 to stop the flow of each source gas, and once in the deposition chamber,
After raising to a high vacuum, the formation of the layer is terminated. At this time, the film of aC: H or the like has a dynamic hardness value of 300 or more and 1000 using a triangular pyramid diamond stylus having a ridge angle of 115 ° with a tip radius of 0.1 μm or less.
It is preferable to form a film of aC: H or the like so as to satisfy the following. During the film formation, the cylindrical substrate 702 may be rotated at a predetermined speed by a driving device (not shown).

FIG. 8 shows another embodiment of the present invention, which is different from FIG.
FIG. 2 is a schematic view of an example of an apparatus (mass production type) for forming a surface protective layer of an electrophotographic photosensitive member by a plasma CVD method. In FIG. 8, reference numeral 801 denotes a reaction vessel, which has a vacuum tight structure. An exhaust pipe 815 has one end open into the reaction vessel 801 and the other end communicating with an exhaust device (not shown). Reference numeral 816 denotes a discharge space surrounded by the cylindrical substrate 802. The high frequency power supply 812 is electrically connected to the cathode electrode 806 via the high frequency matching box 811. The cylindrical deposition substrate 802 includes:
It is set on the rotating shaft 803 while being set on the holder 807. The procedure of the method of forming an electrophotographic photosensitive member using the apparatus of FIG. 8 is basically the same as that of the method except that the arrangement of the cathode and the base is different and that the base is always driven by the rotating motor 814. This is the same as the method using the film forming apparatus shown in FIG.

A-SiC: H or a-SiC: H formed as a surface protective layer on the surface of the cylindrical substrate to be formed as described above.
The dynamic hardness of a film such as C: H was measured as follows using a film formed on glass by the same procedure. The relationship between the load when the surface of the surface layer sample deposited on the glass was vertically applied to a triangular pyramid diamond stylus having a ridgeline angle of 115 ° or less with a tip radius of 0.1 μm or less, and the indentation depth, The dynamic hardness DH was calculated by applying the formula DH = α × p / d ² . Here, α = 37.8, p: load (gf), d: indentation depth (μm). The indentation depth was set to about 1/5 of the thickness of the outermost a-SiC: H or aC: H film in order to prevent the influence of the underlayer.

Experimental Example 2 Using the apparatus shown in FIG. 5, the edge of the cleaning blade used in the electrophotographic apparatus of the present invention was processed. As shown in FIG.
By rubbing the edge portion of the blade 1 while feeding the wrapping tape 502 of # 3000 to # 3000, it is possible to roughen the blade edge. At this time, as a method of controlling the roughened edge portion to have a desired value of _Ry or Sm, for example, a wrapping tape 5
It is possible by controlling the roughness of No. 02 and the contact pressure of the blade against the wrapping tape. _Ry and Sm of the edge portion of the obtained cleaning blade are “Kosaka L
laboratory Co. Ltd. Was measured by a surf coder SE30D of "".

The various cleaning blades manufactured as described above were installed on a GP605 manufactured by Canon. At this time, a-SiC is used as a base material, and a-SiC: H or a-SiC is formed on the outermost surface by the method of Experimental Example 1 described above.
A surface layer composed of C: H was appropriately prepared, and the dynamic hardness of the surface measured and calculated by the above method was about 800. Then, the frictional force between the photoconductor and the cleaning blade was confirmed by measuring the rotation torque of the photoconductor. The load on each blade is constant. For the measurement of the rotational torque, a torque meter TG type “manufactured by Tohnichi Seisakusho” was used. The results obtained are shown in FIG.

As shown in FIG. 6, it has been found that roughening the edge of the blade makes it possible to reduce the rotational torque without changing the blade load.
In addition, as a method of blade surface roughening, a sand blast method can be used, but from the viewpoint of reproducibility of the processing, it was confirmed that a method using a wrapping tape was excellent.

<Experimental Example 3> The cleaning blade prepared in Experimental Example 2 was mounted on a Canon GP605, and the presence or absence of toner slippage was evaluated. The evaluation was performed by applying toner on the photosensitive drum by a cleaning roller, and observing whether or not the toner was removed by a cleaning blade. In addition, the passing-through of the external additive was evaluated at the same time. Further, evaluation of image defects due to poor cleaning was also performed on solid white images. In each of the above evaluations, a toner having an average particle size of 7.5 μm was used as a developer. Further, a photoreceptor having a-Si as a base is used for the photoreceptor, and a-a-Si is used as a surface protective layer on the outermost surface of the photoreceptor.
A coating of SiC: H or aC: H was prepared by the method of Experimental Example 1, and the surface had a dynamic hardness of about 800.
Met. The configuration of the cleaning device of the GP 605 is the same as that shown in FIG. The obtained results are shown in Tables 1 and 2.

As is clear from the results shown in Table 1 below, the edge of the cleaning blade has a reference length of 0.3 mm.
08 mm and an evaluation length of 0.4 mm, _Ry is 2.
It has been confirmed that toner is not slipped through when the thickness is adjusted to be in the range of 0 μm or more and 15.0 μm or less, and the average interval Sm of the unevenness is adjusted to be in the range of 3.0 μm or more and 25.0 μm or less. did it. On the other hand, it was confirmed that, within the above range, the external additive in the toner could selectively pass through the cleaning blade and the surface of the photoconductor.

[0037]

[Table 1]

Further, as shown in Table 2 below, the edge of the cleaning blade has a reference length of 0.08 mm,
Adjusted so that, at the evaluation length of 0.4 mm, _Ry is in the range of 1.0 μm to 15.0 μm, and the average interval Sm of unevenness is in the range of 5.0 μm to 25.0 μm. In this case, although the external additive slips through, there is no image defect which causes a practical problem in image formation, and a good image can be obtained.

[0039]

[Table 2]

As described above, in the electrophotographic apparatus according to the present invention using the cleaning blade having a specific edge shape, as shown in FIG. 6, the photosensitive drum and the cleaning blade can be moved without changing the blade load. It was found that the torque could be reduced, and as shown in Tables 1 and 2, only the external additive of the toner could pass through the cleaning blade, and a good image could be obtained.

<Experimental Example 4> The cleaning blade used in Experimental Example 2 was mounted on a Canon GP605, and the photosensitive drum was rotated for 24 hours without supplying toner, to perform a durability test of the cleaning blade. At this time, the surface speed of the photosensitive drum was 300 mm / sec. Further, a photoreceptor having a-Si as a base is used as the photoreceptor, and a-SiC: H or aC: H is appropriately formed on the outermost surface of the photoreceptor by the method of Experimental Example 1. The dynamic hardness was about 800 in each case. After 24 hours, apply toner to the cleaning blade and cleaning roller,
The presence or absence of cleaning failure was confirmed by image evaluation. The results are shown in Table 3.

[0042]

[Table 3]

As is evident from the results in Table 3, the cleaning blade used in the present invention exhibited very good durability performance even in the durability test without toner.
On the other hand, in a durability test of a conventional cleaning blade in which toner was not interposed, it was found that the blade edge was easily damaged because the frictional force was large. Further, when the value of _Ry does not exceed 2.0 μm,
2. μm blade, the value of Sm does not exceed 5.0 μm
With respect to the blade having a thickness of 0 μm, the result was the same as that of the conventional blade, and a good result as in the present invention could not be obtained.

<Experimental Example 5> The same cleaning blade as that used in Experimental Example 4 was mounted on a Canon GP605, and 500,000 sheets were passed without a cleaning roller to evaluate the cleaning performance. . At this time, a photoreceptor having a-Si as a base was used as the photoreceptor, and a-SiC: H or aC: H was formed on the outermost surface of the photoreceptor by the method of Experimental Example 1. Hardness of about 800 was used. The evaluation was made on the cleaning properties during the endurance (blade chipping, curling of the blade) and the shaving unevenness of the photoconductor. The results are shown in Table 4.

[0045]

[Table 4]

As shown in Table 4, even in a durability test without a cleaning roller, the cleaning blade used in the present invention does not cause poor cleaning and uneven shaving of the photosensitive member, and has very good durability performance. showed that.
On the other hand, it has been found that in the conventional product, the difference in the shaved amount of the photoreceptor occurs in a portion where the toner does not intervene in the cleaning blade, and shaving unevenness occurs. Further, the value of _Ry is 1.0 μm
Blade having a Sm value not exceeding 5.0 μm 3.0 μm
For m, the result was the same as that of the conventional blade, and as in Experimental Example 5, good results as in the present invention could not be obtained.

<Experimental Example 6> The same cleaning blade as used in Experimental Example 4 was mounted on a Canon GP605, a cleaning device having the structure shown in FIG. 3 was provided, and toner was applied to the photosensitive drum by a cleaning roller. A 500,000-sheet durability test was performed while cleaning performance was evaluated. At this time, a photoreceptor having a-Si as a base was used as the photoreceptor, and a-SiC: H or aC: H was formed on the outermost surface of the photoreceptor by the method of Experimental Example 1. Hardness of about 800 was used. The evaluation was performed by evaluating the cleaning property during the endurance (blade chipping and blade curling) and the abrasion loss of the photoconductor after the endurance to evaluate the unevenness of the photoreceptor shaving. Table 5 shows the results.

[0048]

[Table 5]

As shown in Table 5, in the cleaning blade used in the present invention, no defective cleaning and no unevenness of the photosensitive member were generated. Experimental Examples 3 to 6 above
From the results of the above, taking into consideration the durability of the cleaning blade, the cleaning blade used in the electrophotographic apparatus of the present invention has a roughened edge, and further has a reference length of 0.08 mm and an evaluation length of 0. At 0.4 mm, _Ry is in the range of 2.0 μm or more and 15.0 μm or less, and the average interval Sm of unevenness is 5.0 μm or more and 2 μm or more.
It is an essential requirement that the adjustment is performed so as to be within a range of 5.0 μm or less.

<Experimental Example 7> The same durability test as in Experimental Example 6 was carried out for 5 million sheets, and the shaving amount of the surface layer of the photosensitive drum was measured. The thickness of the surface layer of the photoreceptor is SPE manufactured by Otsuka Electronics Co., Ltd.
CTOR MULYI CHANNEL PHOTO
It was measured by light interference using a DETECTOR (MCPD). From the obtained measurement results, the degree (ratio) of scraping was calculated and shown in Table 6. As shown in Table 6, the amount of shaving of the cleaning blade of the present invention was smaller than the amount of shaving of the conventional cleaning blade. That is, if the specific cleaning blade used in the present invention is used,
Since the life of the photoconductor can be extended and the thickness of the surface layer can be reduced, the cost of the photoconductor can be reduced.

[0051]

[Table 6]

As described above, as shown in Experimental Examples 3 to 6 (see Tables 1 to 5), when the cleaning blade used in the present invention is used, the rotation torque of the photosensitive member can be reduced without changing the load of the cleaning blade. It is possible to reduce the frictional force between the photoconductor and the cleaning blade,
This has the effect of preventing blade turning and toner fusion, which have conventionally been problems. Further, since the uniformization of the blade contact pressure is promoted, even when toner is hardly supplied to the blade (see Experimental Example 4), uneven shaving of the photoreceptor hardly occurs. Further, the life of the photosensitive member and the life of the cleaning blade can be extended (Experimental Examples 4 to 7 (see Tables 3 to 6)). Observation of the blade state after the durability in the above-described experimental example confirmed that damage was extremely small when the values of _Ry and Sm were within the ranges specified in the present invention. This is considered to be due to the effect that the external additive was positively passed through at the contact portion between the photoconductor and the blade. On the other hand, in the conventional blade, minute damage was unevenly present, and the degree of damage was larger than that used in the present invention.

[0053]

The present invention will be described below in more detail with reference to examples of the present invention. The present invention is not limited thereto. [Example 1] _Ry = 5 and Sm =
Using 10 cleaning blades, the copier NP6750 manufactured by Canon Inc. was equipped, and a durability test of 3 million sheets was performed. The configuration of the cleaning device was the configuration shown in FIG. 3, and a magnetic roller was used as the cleaning roller. The photoreceptor had an outer diameter of φ80 mm, and used a-SiC as a base material and having a-SiC: H and aC: H films on the surface layer, respectively. Each dynamic hardness is a-Si
C: H was 500 and aC: H was 600.
When poor cleaning during the durability test and uneven shaving of the photosensitive drum surface layer after the durability test were evaluated, no poor cleaning occurred and almost no uneven shaving of the surface layer.

Example 2 R _y = good in the experimental example
Using a cleaning blade of 5 and Sm = 10, the copier NP6750 manufactured by Canon Inc. was equipped, and a durability test of 3 million sheets was performed. The configuration of the cleaning device was the configuration shown in FIG. 3, and a fur brush roller was used as the cleaning roller. The photoreceptor has an outer diameter of φ80 mm,
a-SiC: H and aC;
Photoconductors each having an H film were used. The respective dynamic hardnesses were 500 when the a-SiC: H film was provided, and 600 for aC: H. When the poor cleaning during the durability test and the uneven shaving of the surface layer of the photosensitive drum after the durability test were evaluated, no poor cleaning occurred and there was almost no uneven shaving of the surface layer.

Example 3 R _y = good in the experimental example
Using a cleaning blade of 5 and Sm = 10, the copier NP6750 manufactured by Canon Inc. was equipped, and a durability test of 3 million sheets was performed. The configuration of the cleaning device was the configuration shown in FIG. 3, and a sponge roller was used as the cleaning roller. The photoreceptor has an outer diameter of φ80 mm, and a-
A photoreceptor having Si as a base material and having a-SiC: H and aC: H films as surface layers, respectively, was used. As for each dynamic hardness, a-SiC: H was 500 and aC: H was 600. When the poor cleaning during the durability test and the uneven shaving of the surface layer of the photosensitive drum after the durability test were evaluated, no poor cleaning occurred and there was almost no uneven shaving of the surface layer.

Example 4 R _y = good in the experimental example
Using a cleaning blade of 5 and Sm = 10, the copying machine GP605 made by Canon was equipped, and a durability test of 3 million sheets was performed. The configuration of the cleaner was the configuration shown in FIG. 3, and a magnetic brush roller was used as the cleaning roller. The photoreceptor has an outer diameter of φ108 mm and a-Si
And a photoreceptor having a-SiC: H and aC: H in the surface layer, respectively. Each dynamic hardness is a
-SiC: H was 500, and aC: H was 600.
When the poor cleaning during the durability test and the uneven shaving of the surface layer of the photosensitive drum after the durability test were evaluated, no poor cleaning occurred and there was almost no uneven shaving of the surface layer.

Example 5 R _y = good in the experimental example
5 and Sm = 10 blades were used with Canon copier GP6
05, and a durability test of 3 million sheets was performed. The configuration of the cleaner was the configuration shown in FIG. 3, and a fur brush roller was used as the cleaning roller. The photoreceptor has an outer diameter of φ80 mm and a-Si
Photoconductors each having -SiC: H and aC: H were used. Each dynamic hardness is a-SiC: H of 50
0, aC: H was 600. When the poor cleaning during the durability test and the uneven shaving of the surface layer of the photosensitive drum after the durability test were evaluated, no poor cleaning occurred and there was almost no uneven shaving of the surface layer.

Example 6 R _y = good in the experimental example
5 and Sm = 10 blades were used with Canon copier GP6
05, and a durability test of 3 million sheets was performed. The structure of the cleaner was the structure shown in FIG. 3, and a sponge roller was used as the cleaning roller. The photoreceptor has an outer diameter of φ108 mm.
Photoconductors each having -SiC: H and aC: H were used. Each dynamic hardness is a-SiC: H of 50
0, aC: H was 600. When the poor cleaning during the durability test and the uneven shaving of the surface layer of the photosensitive drum after the durability test were evaluated, no poor cleaning occurred and there was almost no uneven shaving of the surface layer.

Example 7 R _y = good in the experimental example
5 and Sm = 10 blades are used with Canon copier GP2
15 and subjected to a durability test of one million sheets. The configuration of the cleaner was the configuration shown in FIG. 3, and a magnetic roller was used as the cleaning roller. Photoreceptor has outer diameter φ
30 mm, and a-Si is used as a base and a-Si
Photoconductors each having C: H and aC: H were used. Each dynamic hardness is a-SiC: H 500, a-SiC: H
C: H was 600. When the poor cleaning during the durability test and the uneven shaving of the surface layer of the photosensitive drum after the durability test were evaluated, no poor cleaning occurred and there was almost no uneven shaving of the surface layer.

Example 8 R _y = good in the experimental example
5 and Sm = 10 blades are used with Canon copier GP2
15 and subjected to a durability test of one million sheets. The configuration of the cleaner was the configuration shown in FIG. 3, and a fur brush roller was used as the cleaning roller. The photoreceptor had an outer diameter of φ30 mm, and used a photoreceptor having a-Si as a base material and a-SiC: H and aC: H in the surface layer, respectively. Each dynamic hardness is a-SiC: H of 50
0, aC: H was 600. When the poor cleaning during the durability test and the uneven shaving of the surface layer of the photosensitive drum after the durability test were evaluated, no poor cleaning occurred and there was almost no uneven shaving of the surface layer.

Example 9 R _y = good in the experimental example
5 and Sm = 10 blades are used with Canon copier GP2
15 and subjected to a durability test of one million sheets. The structure of the cleaner was the structure shown in FIG. 3, and a sponge roller was used as the cleaning roller. The photoreceptor has an outer diameter of φ30 mm.
Photoconductors each having SiC: H and aC: H were used.
Each dynamic hardness is a-SiC: H is 500,
aC: H was 600. When the poor cleaning during the durability test and the uneven shaving of the surface layer of the photosensitive drum after the durability test were evaluated, no poor cleaning occurred and there was almost no uneven shaving of the surface layer.

[0062]

As described above, according to the present invention,
By using a cleaning blade with a roughened edge portion and a specific uneven state, good cleaning performance without shaving unevenness and poor cleaning is maintained for a long time, especially in combination with a photoconductor having a large dynamic hardness. As a result of prolonging the life of the blade, in an electrophotographic apparatus having a cleaning means for cleaning the surface of the photoreceptor, the life of the photoreceptor drum and the cleaning blade is not reduced, and fine powder such as colloidal silica is externally added. Even when a toner used as an agent is used, an electrophotographic apparatus capable of performing good cleaning of the surface of a photoreceptor and providing a good image for a long period of time is provided.

[Brief description of the drawings]

FIG. 1A is a schematic view showing an example of an edge portion of a conventionally used cleaning blade, and FIGS. 1B and 1C are diagrams of an edge portion of a cleaning blade used in the electrophotographic apparatus of the present invention. It is a schematic diagram showing an example.

FIG. 2 is a schematic diagram showing a cleaning step.

FIG. 3 is a schematic diagram of a cleaning device.

FIG. 4 is a schematic diagram illustrating an example of an electrophotographic apparatus.

FIG. 5 is a schematic view showing an example of a method for forming an edge portion of a cleaning blade used in the electrophotographic apparatus of the present invention.

FIG. 6 is an example of a graph showing a relationship between _Ry , Sm, and torque of a cleaning blade.

FIG. 7 is an example of a film forming apparatus used for forming a surface protective layer of a photoconductor.

FIG. 8 is another example of a film forming apparatus used for manufacturing a surface protective layer of a photoconductor.

[Explanation of symbols]

 101: photosensitive member 102: main charger 103: electrostatic latent image forming portion 104: developing device 105: transfer paper supply system 106: (a) transfer charger, (b) separation charger 107: cleaning device 108: transport system 109: Static elimination light source 110: Lamp 111: Original platen glass 112: Original document 113 to 116: Mirror 117: Lens unit 118: Lens 119: Transfer paper guide 120, 302, 501: Cleaning blade 121, 303: Cleaning roller 122: Registration roller 123: fixing device 124: fixing roller P: transfer paper 301: outer shell of cleaning device 304: doctor roller (or scraper) 305: waste toner reservoir 306: waste toner transport system 502: wrapping tape 503: pressing roller 701, 801: Reaction vessel 70 , 802: cylindrical film-forming substrate 704: main valve 705: source gas inlet 706, 806: cathode electrode 709: valve 710: vacuum gauge 803: rotating shaft 807: holder 811: high frequency matching box 812: high frequency power supply 814: Rotary motor 815: exhaust pipe 816: discharge space

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hironori Owaki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kunimasa Kawamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside (72) Inventor Toshiyuki Ehara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Koji Yamazaki 3-30-2, Shimomaruko, Ota-ku, Tokyo Canon Inc. F Term (reference) 2H034 AA06 BC01 BC09 BD01 BF01 BF03 CB01 2H068 DA05 DA17 DA23 FA03 FC15

Claims (5)

[Claims] 1. A charging device for charging an electrophotographic photosensitive member, a latent image forming device for exposing the charged electrophotographic photosensitive member to form a latent image, and developing the latent image with toner to form a toner image Developing means, transfer means for transferring the toner image to a transfer material,
An electrophotographic apparatus that has a cleaning unit that removes a residue and / or a foreign substance on the surface of the electrophotographic photosensitive member with a cleaning blade, and that repeatedly performs image formation using the electrophotographic photosensitive member cleaned by the cleaning unit; The toner has at least toner particles and an external additive, and the cleaning blade is a blade made of a band-shaped elastic body, and the edge of a portion of the cleaning blade that contacts the photoconductor is roughened and has a reference length. At 0.08 mm and the evaluation length of 0.4 mm, the maximum height _Ry is in the range of 2.0 μm or more and 15.0 μm or less, and the average interval Sm of the unevenness is 5.0 μm or more and 25.0 μm or less. It is adjusted to be within the range, and the external additive in the toner selectively passes through the cleaning blade and the photoconductor surface. An electrophotographic apparatus, characterized in that the apparatus is configured to be capable of causing the electrophotographic apparatus to operate. 2. The dynamic hardness of an electrophotographic photoreceptor in the range of 300 to 1,000 when a triangular pyramid diamond stylus having an edge angle of 115 ° with a tip radius of 0.1 μm or less on the outermost surface is used. The electrophotographic apparatus according to claim 1. 3. An electrophotographic photoreceptor having a light receiving portion layer and a surface protective layer, wherein the light receiving portion layer contains at least amorphous silicon and the surface protective layer contains amorphous silicon carbide. The electrophotographic apparatus according to claim 1 or 2, wherein 4. An electrophotographic photoreceptor having a light receiving portion layer and a surface protective layer, wherein the light receiving portion layer contains at least amorphous silicon and the surface protective layer contains amorphous carbon. The electrophotographic apparatus according to claim 1 or 2, wherein 5. The cleaning blade processing method using a wrapping tape, wherein the edge of a portion of the cleaning blade that contacts the photoconductor is roughened.
The electrophotographic apparatus according to claim 1.