JPH0619377A - Electrophotographic sensitive drum, and process cartridge for electrophotography and electrophotographic device using the same - Google Patents

Abstract

PURPOSE:To obtain the photosensitive drum which provides silent operation by damping vibration when electrostatically charged with an alternating electric field and is easily manufactured and well recycled, and the process cartridge and electrophotographic device which are equipped with this photosensitive drum. CONSTITUTION:A photoconductive layer 12 is provided as a photosensitive layer around the outer periphery of a base body 11 and a driving transmission gear 13 and a bearing flange 14 are fixed to both the ends of the base body 11. A filler which is sectioned in a channel shape is put in the hollow cylindrical body 11 so that the external-diameter part is pressed against the base body 11. The base 11 is filled with liquid, liquid and powder, or powder. A coil spring whose outer periphery contacts the inner periphery of the base body 11 is inserted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process cartridge and an electrophotographic apparatus for an electrophotographic apparatus having a contact charging member, and an electrophotographic photosensitive drum used for them.

[0002]

2. Description of the Related Art An electrophotographic photosensitive drum is generally constructed by forming a photoconductive film on a conductive cylindrical substrate. Aluminum is often used as the conductive substrate. Recently, with the downsizing of electrophotographic apparatuses, electrophotographic photosensitive drums are also becoming smaller and lighter.

On the other hand, as a charging device used in an electrophotographic apparatus, a corona discharge device has been generally used conventionally. However, recently, because it has advantages such as a low power supply voltage and an extremely small amount of ozone generated, a direct charging device for bringing a roller-type or blade-type conductive member into contact with a photoconductor is adopted. Is being done.

[0004]

In such direct charging, an AC voltage is applied in order to uniformly carry out charging. However, due to the application of the AC voltage, the electrophotographic photosensitive drum and the contact charging member vibrate and generate a sound by hitting each other. This sound is offensive to the ears, and it can be said that countermeasures are indispensable as the quietness of office equipment is required in recent years. In the past, in order to reduce this noise, measures have been taken to reduce the frequency of the AC voltage. However, that means tends to cause uneven charging, and there is a limit to the speedup of the electrophotographic apparatus. Further, in an electrophotographic apparatus whose image input is a digital signal, such as a laser beam printer, when the input pixel density is increased to improve the image quality, there is a problem that uneven charging due to the frequency decrease is more likely to appear.

An object of the present invention is to provide an electrophotographic photosensitive drum having an effect of preventing the above-mentioned sound generated by direct charging. Further, it is also an object of the present invention to provide a process cartridge and an electrophotographic apparatus using such a photosensitive drum, which can achieve high speed, high image quality, and high quietness.

[0006]

SUMMARY OF THE INVENTION According to the present invention, in order to prevent a sound generated directly between a charging member and an electrophotographic photosensitive drum by application of an AC voltage, the weight per volume of the photosensitive drum is set to a certain value or more. It is considered that this produces an effect of absorbing vibration. Accordingly, the weight to the total volume of the photosensitive drum is 0.65 g / cm ³ or more, more preferably effect is obtained when it is 0.8 g / cm ³ or more, sound if less than 0.65 g / cm ³ The effect of preventing is not sufficient.

The first invention of the present invention comprises a photosensitive layer provided on a cylindrical substrate, and a drive transmission member, a bearing member, etc., coupled to the end of the substrate, and is directly charged by a contact charging member. In the electrophotographic photosensitive drum according to the present invention, by inserting a filler having a columnar shape or a cylindrical shape and having a C-shaped cross section perpendicular to the axial direction into the base, Weight for product is 0.65g / c
The electrophotographic photosensitive drum is characterized in that it is m ³ or more.

According to a second aspect of the present invention, the axial center of the filler having a C-shaped cross section perpendicular to the axial direction is located at a position where it coincides with the axial center of the base of the photosensitive drum. The electrophotographic photosensitive drum according to the first invention is inserted.

According to a third aspect of the present invention, the filler having a C-shaped cross section perpendicular to the axial direction is contracted and accommodated in the base body, and is held and fixed to the base body only by the restoring force due to its spring force. The electrophotographic photosensitive drum according to the second aspect of the invention.

A fourth invention of the present invention is an electrophotographic process cartridge comprising at least a photosensitive drum, a contact charging member and a developing means, wherein the photosensitive drum is any one of the first invention to the third invention. And an electrophotographic process cartridge for electrophotography.

A fifth invention of the present invention is an electrophotographic apparatus using at least a photosensitive drum, a contact charging member, an exposing means, a developing means, and a transferring means, wherein the photosensitive drum is any one of the first invention to the third invention. And an electrophotographic photosensitive drum according to item 1.

According to the sixth to eighth aspects of the present invention, a photosensitive layer provided on a cylindrical substrate and a drive transmission member, a bearing member and the like are coupled to the end of the substrate, and a contact charging member is used. In an electrophotographic photosensitive drum that is directly charged, the weight of the electrophotographic photosensitive drum with respect to the total volume of the electrophotographic photosensitive drum is set to 0.65 g / cm ³ or more by filling the substrate with a liquid. Provided are a drum, an electrophotographic process cartridge using the drum, and an electrophotographic apparatus. The sixth to eighth inventions are characterized in that the photosensitive drum is filled with a liquid as a means for giving a weight.

The ninth to eleventh aspects of the present invention are composed of a photosensitive layer provided on a cylindrical substrate, and a drive transmission member, a bearing member and the like connected to the end of the substrate. In an electrophotographic photosensitive drum that is directly charged, the weight of the electrophotographic photosensitive drum with respect to the total volume is 0.65 g / cm 2 by filling the base with powder and liquid.
^{The present} invention provides an electrophotographic photosensitive drum characterized by having ³ or more, and an electrophotographic process cartridge and an electrophotographic apparatus using the same. The ninth to eleventh inventions are characterized by filling the photosensitive drum with powder and particles as a means for imparting weight.

In the twelfth to fourteenth aspects of the present invention, a photosensitive layer provided on a cylindrical substrate and a drive transmission member, a bearing member and the like are coupled to the end of the substrate, and a contact charging member is used. In an electrophotographic photosensitive drum that is directly charged, the base is filled with a powder or granular material so that the weight of the electrophotographic photosensitive member with respect to the total volume is 0.65 g / cm ³ or more. The present invention provides a photographic photosensitive drum, an electrophotographic process cartridge using the same, and an electrophotographic apparatus. The twelfth to fourteenth inventions are characterized in that powder particles are filled as means for imparting weight to the photosensitive drum.

A fifteenth invention of the present invention comprises a photosensitive layer provided on a cylindrical substrate, and a drive transmission member, a bearing member, etc., coupled to the end of the substrate, and is directly charged by a contact charging member. In the electrophotographic photosensitive drum according to
By inserting a filler having a coil spring-like shape, the weight of the entire electrophotographic photosensitive drum is 0.6%.
The electrophotographic photosensitive drum is characterized by having a content of 5 g / cm ³ or more.

The sixteenth invention of the present invention is the fifteenth invention, wherein the axial center of the filler having the coil spring-like shape is inserted in such a position as to coincide with the axial center of the base of the photosensitive drum. The electrophotographic photosensitive drum described in 1.

The seventeenth invention of the present invention is characterized in that the filler having the above coil spring-like shape is held and fixed to the substrate only by the restoring force of its springiness. It's a drum.

An eighteenth aspect of the present invention is an electrophotographic process cartridge comprising at least a photosensitive drum, a contact charging member and a developing means, wherein the photosensitive drum is the electrophotographic photosensitive member according to any one of claims 15 to 17. The electrophotographic cartridge is characterized by using a drum.

A nineteenth invention of the present invention is an electrophotographic apparatus comprising at least a photosensitive drum, a contact charging member, an exposing means, a developing means, and a transferring means, wherein the photosensitive drum is any one of the fifteenth invention to the seventeenth invention. An electrophotographic apparatus comprising the electrophotographic photosensitive drum described in 1.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. The photosensitive drum described below is applied to the electrophotographic apparatus and process cartridge described below.

FIG. 3 shows an electrophotographic apparatus. Photosensitive drum 1
The drive members and the like are omitted. Around the photosensitive drum 1, a cleaning device 3, a charge eliminating lamp 4, a charging roller 5 as a contact charging member, an exposing device 6, a developing device 7 as a developing device, and a transfer roller 8 as a transferring device are arranged. Further, a paper feeding / conveying device for the recording paper 2 is arranged on the right side of the transfer roller 8 and a fixing device 9 for fixing the developer on the recording paper 2 is arranged on the running line of the recording paper 2 on the left side. In addition to the roller shape shown here, a known shape such as a blade shape can be used for the contact charging member. As a material of the contact charging member, an elastic body having conductivity is generally used. As the voltage applied to the contact charging member, an oscillating voltage obtained by superimposing an AC voltage on a DC voltage is preferable. The oscillating voltage mentioned here is a voltage whose voltage value periodically changes with time, and the AC voltage may have a peak-to-peak voltage that is at least twice the charging start voltage of the photoconductor when only the DC voltage is applied. preferable. Further, the waveform is not limited to a sine wave, and may be a rectangular wave, a triangular wave, or a pulse wave, but from the viewpoint of sound, a sine wave that does not include a harmonic component is preferable.

Since the other construction is basically the same as that of a normal electrophotographic apparatus, detailed description thereof will be omitted.
Further, in the present invention, a plurality of constituent elements arranged around the photosensitive drum may be integrally combined as an apparatus unit, and the unit may be detachably attached to the entire apparatus. An example thereof is shown in FIG. FIG. 4 shows the photosensitive drum 1, the charging roller 5, the developing device 7,
The cleaning device 3 is housed in the case 15.

FIG. 1 shows a photosensitive drum. Cylindrical base 1
1 is almost equal to the total length of the photosensitive drum. It has a photosensitive layer 12 formed on a substrate 11. The drive transmission gear 13 is fixed to one end of the base 11, and the bearing flange 14 is fixed to the other end. A conductive member for establishing electrical continuity between the base 11 and the electrophotographic apparatus may be disposed inside the base (not shown).

The drive transmission gear 13 and the bearing flange 14 close both ends of the base body 11, and at the center thereof, a cylindrical concave portion or convex portion is provided as a bearing portion. When the photosensitive drum 1 is supported by a fixed shaft penetrating the photosensitive drum 1, a pipe inserted into the shaft is provided between the drive transmission gear 13 and the bearing flange 14, and in any case, the inner and outer circumferences are sealed. It is in.

The substrate 11 of the photosensitive drum 1 may basically be any as long as it can be formed into a cylindrical shape, but in consideration of formability, workability, strength required for inserting a filler, and the like. Metals, especially aluminum, are then suitable.

The photosensitive layer 12 provided on the substrate 11 is not particularly limited, and a known photoconductive material may be formed by a known means. However, in terms of directly contacting the charging member with the photosensitive layer 12, the photosensitive drum 1 having on its surface an organic photoconductive material formed by using a resin as a base.
Is preferred. In the case of a photosensitive layer mainly composed of an organic material,
A configuration in which a plurality of layers are laminated is common.

The drum drive transmission gear 13 and the bearing flange 14 fixed to at least one terminal of the base 11 on which the photosensitive layer 12 is formed contributes to the weight of the photosensitive drum 1.
As the material, aluminum, polycarbonate, polyacetal or the like is used from the viewpoint of moldability, workability, slidability, durability and the like.

[First Embodiment] FIGS. 5 and 6 show the shape of the filler 20 in the photosensitive drum 1 used in the present invention, but the present invention is not limited to this. The filling 20 has a cylindrical cross section perpendicular to the axial direction, is a hollow cylinder having slits 20a along the generatrix, and has a C-shape. The outer circumference of the filling 20 is larger than the outer circumference of the base 11,
When the outer circumference of the base material 11 is reduced so as to be housed in the inner circumference of the base material 11, the outer circumference of the base material 11 becomes a cylindrical shape. Further, when the filling material 20 accommodated in the base 11 is reduced and accommodated, it is pressed and fixed to the base 11 in an attempt to restore it by its spring force. The fixing force is the movement during the rotation of the photosensitive drum 1. The filler 20 should not move with respect to the substrate 11 depending on transportation and handling, but on the other hand, it is necessary that the filler 20 be disassembled in preparation for disassembly when the photosensitive drum is recycled.

7 and 8 show another example of the filling material 20, and the slit is a spiral slit 20b. Each filling 2
No. 0 slits 20a, 20b are provided on both sides with axial tool engaging holes 20c.
The filler 20 can be reduced in diameter by inserting a tool into c and shrinking the space between the two tool engagement holes 20c. When the wall thickness of the filling material 20 becomes extremely thick, the filling material 20 has a shape in which a slit 20a or 20b is provided in a column. The outer peripheral surface of the filling material 20 of the present invention is required to be substantially in contact with the inner wall of the base 11 in order to absorb the vibration generated by the charging of the photosensitive drum 1, and for that reason, rubber, urethane, vinyl or the like is used. It may be covered with a synthetic resin material. Further, as the material of the rigid body, any material may be used as long as the weight of the photosensitive drum when it is inserted satisfies the conditions of the present invention and has a restoring force, but spring steel, chrome vanadium described in JIS Metal materials such as steel, manganese chrome steel, stainless steel and phosphor bronze, and plastic materials such as FRP are preferable, and further, the density is preferably 2.0 g / cm ³ or more. This is because the higher the density, the higher the effect of absorbing sound vibrations, and the smaller the size for obtaining the necessary weight, so that the insertion is easier and the productivity is improved. It may be appropriately selected from these, considering various factors such as workability, productivity, and cost.
The length of the filling material may satisfy the weight per volume of the present invention in the state of being inserted into the photosensitive drum 1, but it is generally preferable that it is shorter than the length of the base 11. When the length is shorter than the length of the base 11, it is effective to insert the filler at the center of the base 11. That is, it is preferable that the center of the filler in the axial direction is inserted at a position where it coincides with the center of the substrate 11 of the photosensitive drum 1 in the axial direction. Further, a plurality of packings may be used, but in that case, the base 1
It is effective to arrange the packing so as to be symmetrical in the length direction of 1.

In order to disassemble the photosensitive drum 1 for recycling, the drive transmission gears 13 and the bearing flanges 14 on both sides are removed from the base body 11, and then a tool is inserted into the tool engagement hole 20c, and the space between the tool engagement holes 20c is removed. When the diameter is reduced by drawing, the filling material 20 can be easily removed from the base 11.

Experimental Example 1 As the substrate 11, 30φ, 260 mm, wall thickness 0.75 m
m aluminum cylinder was prepared. Then, layers having the following constitution were sequentially laminated and applied to form a photosensitive layer 12. (1) Conductive coating layer: Mainly composed of tin oxide and titanium oxide powder dispersed in a phenol resin. Film thickness 1
8 μ (2) Undercoat layer: Mainly composed of modified nylon and copolymerized nylon. Thickness 1.0 μ (3) Charge generation layer: Mainly composed of a disazo pigment having absorption in a long wavelength region dispersed in an acrylic resin. Film thickness 0.2 μ (4) Charge transport layer: Mainly composed of a hydrazone compound having hole transportability dissolved in a polycarbonate resin. A film thickness of 25 μ is shown in FIG.
6 shapes, outer diameter 32 mm, wall thickness 6 mm, length 160 mm,
The slit 20a is made of phosphor bronze with a width of 8 mm and weighs 310 g.
An external force was applied to the filling material 20 of No. 1 to insert it in a state where the apparent outside diameter was smaller than the inside diameter of the base body 11, and then was restored in the base body 11 and held and fixed. Further, the electrophotographic photosensitive drum 1 was prepared by fitting the drive transmission gear 13 and the bearing flange 14 made of polycarbonate resin as shown in FIG. . The weight per total volume of the photosensitive drum 1 was 1.70 g / cm ³ .

Next, the photosensitive drum 1 is assembled into a process cartridge having a structure as shown in FIG.
Furthermore, 16 sheets per minute (size A of Japanese Industrial Standard paper
It is mounted on a laser beam printer having a printing speed of 4) and the sound generated by the charging by the charging roller 5 (hereinafter the same) is measured. The conditions of this electrophotographic apparatus are as follows: process speed: 94 mm / sec, DC applied voltage: 700
V, the frequency of the AC applied voltage was 550 Hz, and the peak-to-peak voltage was 2000V. The input pixel density of this printer is 300 dpi. As a method of measuring sound,
The above device is installed in an anechoic chamber with a background noise of 30 dB (A), and the sound level meter "Type NL" is installed at a position corresponding to 50 cm from the front surface of the photosensitive drum 1 (direction perpendicular to the axis of the photosensitive drum 1).
-02 "(manufactured by Rion Co., Ltd.) was installed. The printer is modified so that only the photosensitive drum 1 can be rotationally driven and various other operating sounds are not generated. Therefore, when the photosensitive drum 1 is rotationally driven, the sound pressure XdB (A)
And the sound pressure YdB (A) when the photosensitive drum 1 is rotated and directly charged under the above conditions, and the difference Δ = Y−XdB (A) between them is determined as the sound generated by the charging. It was calculated.

Comparative Example 1 A photosensitive drum was prepared in the same manner as in Experimental Example 1 except that the filler was not inserted in the photosensitive drum, and the photosensitive drum was mounted on the same process cartridge and printer to measure the sound. The weight of the entire photosensitive drum is 0.40 g / cm ³ . The results are shown in Table 1. That is, in Experimental Example 1, the amount of sound increase Δ due to charging is 1 dB (A), but in Comparative Example 1, 7
It was dB (A).

According to the study by the present inventors, it has been confirmed that if the increase Δ of the sound due to charging is 4 dB (if it is below, it is a sound level that is practically no problem including hearing. Therefore, it can be seen from the results in Table 1 that the effects of the present invention are sufficiently obtained.

Experimental Example 2 A stainless steel having the same shape and size as Experimental Example 1 and having a weight of 28.
A photosensitive drum 1 was prepared in the same manner as in Example 1 except that 0 g of the filler 20 was used. The weight per volume of the entire photosensitive drum 1 is 1.6 g / cm ³ . The same process cartridge and printer as in Experimental Example 1 were mounted and the sound was measured. As shown in Table 1, the increase Δ in sound due to charging was 1 dB (A).

Experimental Example 3 A packing 20 made of FRP having a linear slit 20a having the same shape as that of Experimental Example 1 and having an outer diameter of 34φ, a wall thickness of 8 mm, a length of 200 mm, a slit width of 10 mm, and a weight of 200 g was used. The experiment was conducted in the same manner as the experimental example. The weight per volume of the entire photosensitive drum is 1.2 g / cm ³ .

Experimental Example 4 Having a spiral slit 20b, made of phosphor bronze and having an outer diameter of 3
3mm, wall thickness 3mm, length 170mm, slit width 8m
The experiment was performed in the same manner as in Experimental Example 1 except that the filling 20 having a weight of 140 m and a weight of 140 g was used. The weight per volume of the entire photosensitive drum 1 is 0.9 g / cm ³ .

Experimental Example 5 Having a spiral slit 20b, made of stainless steel, outer diameter 33 mm, wall thickness 2 mm, length 170 mm, slit width 8
Experiments were performed in the same manner as in Experimental Example 1 except that the filling 20 having a weight of 70 mm and a weight of 70 g was used. The weight per volume of the entire photosensitive drum 1 is 0.65 g / cm ³ .

Experimental Example 6 A laser beam printer, which is an electrophotographic apparatus, was modified to have an input pixel density of 600 dpi, an AC voltage frequency of 650 Hz, and a process speed of 110 mm / sec.
Evaluation was performed in exactly the same manner as in Experimental Example 1 except that.

Comparative Example 2 The material, diameter, and thickness of the base 11 of the photosensitive drum 1 are the same as those of Experimental Example 2.
The length was set to 346 mm similarly to the above. The sound was measured by mounting the printer on a process cartridge and a printer having the same process speed as in Experimental Example 5 except that the filler was not inserted into the photosensitive drum. The weight per volume of the photosensitive drum 1 is 0.4 g / cm ³ .

The results are also shown in Table 1. As can be seen from this, in Comparative Example 2, the increase in sound due to the increase in the pixel density and the required frequency is 8 dB.
However, in the experimental example of the first embodiment of the present invention, the sound increase amount Δ due to charging is 1 to 4 dB (A), and the sound damping effect is sufficiently exhibited.

Experimental Example 7 As the photosensitive drum 1, the substrate 11 has a length of 346 mm, and the photosensitive layer 12 is the same as in the experimental example 1, but the thickness of the undercoat layer is 0.5 μ (the experimental example described later). 12). F
Made of RP, outer diameter 35 mm, wall thickness 8 mm, length 110 mm,
Two pieces of the filling material 20 weighing 200 g were press-fitted and arranged. Others were measured similarly to Experimental example 6. The weight per volume of the entire photosensitive drum 1 is 1.2 g / cm ³ . In this example, the increase Δ of the sound due to charging was 3 dB (A).

Second Embodiment Next, a second embodiment of the present invention will be described. The structure of the photosensitive drum 1 is as described above. As a method of filling the liquid in the photosensitive drum 1, at least one end of the photosensitive drum 1 is coupled with a bearing flange 14 and the like, and then the liquid 24 is directly injected into an injection port (not shown) (FIG. 9). ), Or a package film 1 in which the liquid 24 is made of a tubular resin in advance
There is a method of inserting the one enclosed in 6 or the like (FIG. 10). Any type of liquid 24 may be used as long as the weight of the photosensitive drum 1 when filled satisfies the conditions of the present invention, but considering that it is used in an electrophotographic apparatus, it is flammable and ignitable. Or odorous, toxic,
Strongly corrosive materials are not preferable. Therefore, water, various oils, glycerin and the like are preferable. If necessary, additives or the like for preventing alteration may be added to these liquids.

It is important that the filling material is in close contact with the inner wall of the base 11 of the photosensitive drum 1. Therefore, when the liquid 24 is directly injected, it is necessary to fill the base 11 so that the base 11 does not remain. Further, when the liquid 24 previously inserted with the package film 16 is inserted, the package film 16 needs to be in close contact with the inner wall of the base 11. Needless to say, the method for fixing the filling at this time may be to fix the material only by press fitting, or to use an adhesive or the like as an auxiliary means depending on the gap with the inner wall of the base 11. The length of the filling material is 0.65 g per volume of the photosensitive drum 1 when inserted into the base 11.
/ Cm ³ or more, but it is generally preferable that the length is shorter than the length of the base 11. When the length is shorter than the length of the base body, it is effective to insert the filler at the center of the base body 11. That is, the axial center of the filling is
It is preferable that the photosensitive drum 1 is inserted in a position that coincides with the axial center of the substrate 11. Further, the packing may be plural, but in that case, it is effective to arrange the packing so as to be symmetrical in the length direction of the base 11.

The substrate 11 of the photosensitive drum 1 and the photosensitive layer 12 provided on the substrate 11 are the same as in the first embodiment. The drum drive transmission gear 13 and the bearing flange 14 fixed to at least one end of the base 11 on which the photosensitive layer 12 is formed are also the same as those in the first embodiment.

In the second embodiment, since the filling material for recycling is a liquid, it is discharged from the inlet. When the tube is inserted, the drive transmission gear 13 and the bearing flange 14 on both sides of the base 11 are removed and taken out.

Next, the present invention will be described with reference to experimental examples.

Experimental Example 8 The substrate 11 and the photosensitive layer 12 are the same as those described in the experimental example. Drive transmission gear 1 fixed to both ends of the photosensitive drum 1
3. The bearing flange 14 is made of polycarbonate resin and is bonded to the base 11 with an adhesive. Next, water was injected from a hole (not shown) of either the drive transmission gear 13 or the bearing flange 14 to fill the inside of the substrate 11, and then the hole was sealed to produce the electrophotographic photosensitive drum 1. The weight per total volume of the photosensitive drum 1 was 1.1 g / cm ³ . Next, this photosensitive drum 1 is installed in the above-mentioned process cartridge, and further, this is set at 16 sheets per minute (A
It was mounted on a laser beam printer having a printing speed of 4), and the sound generated by charging was measured in the same manner as in each of the above-described examples.

Comparative Example 3 A photosensitive drum 1 was prepared in the same manner as in Experimental Example 8 except that the liquid was not injected into the photosensitive drum, and the weight per volume of the photosensitive drum 1 was 0.33 g / cm ^3. The process cartridge and the printer were mounted and the sound was measured. The results are shown in Table 2. That is, in Experimental Example 8 of the present invention, the sound increase Δ due to charging was 2 dB (A), whereas in Comparative Example 3 it was 7 dB (A).

As described above, according to the study by the present inventors, if the increase Δ of the sound due to charging is 4 dB (A) or less, the level of the sound is practically no problem including hearing. Has been confirmed. Therefore, from the results in Table 2,
It can be seen that the effects of the present invention are sufficiently obtained.

Experimental Examples 9 and 10 Glycerin and carbon tetrachloride were used as shown in Table 2 as the packing material, and the photosensitive drum 1 was prepared in the same manner as in Experimental Example 1 except that it was mounted on the same process cartridge and printer. The sound was measured. Weight per volume of photosensitive drum 1 g / cm
³ is 1.3 when filled with glycerin and 1.45 when filled with carbon tetrachloride. The resulting sound increase Δ due to charging is 2 dB (A) in Experimental Example 9 and 1 dB (A) in Experimental Example 10, and is sufficiently effective as compared with Δ of 7 dB (A) in Comparative Example 3.

Experimental Example 11 The same as Experimental Example 8 except that the input pixel density was set to 600 dpi and the frequency of the applied AC voltage was set to 650 Hz by modifying the laser beam printer which is an electrophotographic apparatus. And evaluated.

Comparative Example 4 The sound was measured by mounting the same on a process cartridge and a printer as in Experimental Example 11 except that the filler was not inserted in the photosensitive drum 1. The weight per volume of the photosensitive drum 1 is 0.33 g / cm ³ .

The results are also shown in Table 2. As can be seen from this, in Comparative Example 4, the increase Δ in sound due to the increase in the pixel density and the required frequency is 10d.
However, in Experimental Example 11, the sound increase Δ due to charging is 3 dB (A), and the sound damping effect is sufficiently exhibited.

Experimental Example 12 The substrate 11 of the photosensitive drum 1 has an outer diameter of 30 mm and a length of 3
An aluminum cylinder having a thickness of 46 mm and a wall thickness of 0.75 mm was prepared. A photosensitive layer was formed by sequentially laminating and coating layers having the following constitution. (1) Conductive coating layer: Mainly composed of tin oxide and titanium oxide powder dispersed in a phenol resin. Film thickness 1
8μ (2) Undercoat layer: Mainly composed of deformed nylon and copolymerized nylon. Film thickness 0.5 μ (3) Charge generation layer: Mainly composed of a disazo pigment having absorption in the visible light region dispersed in petitral resin. Film thickness 0.2 μ (4) Charge transport layer: Mainly composed of a triphenylamine compound having hole transportability dissolved in a polycarbonate resin. A film thickness of 25μ is filled with a product in which water is sealed in a polyethylene tube as shown in FIG. 10, and the drive transmission gear 13 and the bearing flange 14 are bonded by an adhesive as in the experimental example, and the electrophotographic photosensitive drum 1 is fixed. Created.
The total weight of this photosensitive drum is 1.0 g / cm ^3.
Met.

An electrophotographic apparatus was prepared by modifying a plain paper copying machine "Model name NP-2020" (manufactured by Canon Inc.) so that it could be directly charged as shown in FIG.
The copying speed of this copying machine is 20 sheets per minute (A4). Also, the charging condition is that the process speed is 120 mm.
/ Sec, the DC applied voltage is 730 V, the AC applied voltage has a frequency of 800 Hz, and the peak-to-peak voltage is 2200 V.
The sound was measured using the photosensitive drum 1 and the device in the same manner as in Experimental Example 8. As shown in Table 2, the sound increase Δ due to charging was 3 dB (A).

[Embodiment 3] In the present invention, the photosensitive drum 1 is filled with powder and particles and liquid. As a method of filling the photosensitive drum 1 with the filler in which the powder and particles are mixed with the liquid, the bearing flange 14 or the like is coupled to at least one end of the photosensitive drum 1, and then the powder and the liquid are directly added. How to inject,
Alternatively, there is a method in which the granular material and the liquid are sealed in advance in a tubular resin film, a cylindrical synthetic resin case, or the like, and the method is inserted into the base 11. The types of the powdery particles and the liquid may be any as long as the weight of the photosensitive drum 1 when filled satisfies the conditions of the present invention, but considering that they are used in an electrophotographic apparatus, Flammable or ignitable substances, strong odor substances, toxic substances, corrosive substances, and easily magnetized substances are not preferable. Therefore, plastic particles, non-magnetic metal powder, ceramic particles, water, glycerin, various oils and the like are preferable. If necessary, additives or the like for preventing alteration may be added to these powders and liquids.

The ratio of the powdery particles to the liquid may be any ratio as long as the total volume of the photosensitive drum 1 satisfies the weight per volume. It is important that the filling material is in close contact with the inner wall of the base 11 of the photosensitive drum 1. Therefore, in the case of directly injecting the granular material and the liquid, it is necessary to fill the base 11 so that the granular material and the liquid do not flow. Further, in the case of inserting a product in which the powder and granules and the liquid are packaged in advance, it is necessary that the package film is brought into close contact with the inner wall of the base 11. At this time, as a method of fixing the filling,
It goes without saying that fixing may be performed only by press fitting, or an adhesive or the like may be used together as an auxiliary means depending on the gap with the inner wall of the base 11. The length of the filling material 34 may be such a length as to satisfy the weight per volume of 0.65 g / cm ³ with respect to the total volume of the photosensitive drum 1 in a state where it is inserted in the photosensitive drum. The decomposition method at the time of recycling of this Example 3 is the same as that of Example 2.

Next, an experimental example of the third embodiment will be described.

Experimental Example 13 In the same photosensitive drum 1 as in Experimental Example 8, a tube containing aluminum powder and water was filled in a substrate 11, and then a drive transmission gear made of a polycarbonate resin as illustrated in FIG. 13 and the bearing flange 14 were joined by an adhesive.

The total weight of the photosensitive drum 1 was 1.12 g / cm ³ . Next, this photosensitive drum 1
Was incorporated in a process cartridge having the configuration as illustrated in FIG. 4, and the process cartridge was mounted in the same laser beam printer as in Experimental Example 1, and the same measurement as in Experimental Example 1 was performed.

Comparative Example 5 A photosensitive drum 1 was prepared in the same manner as in Experimental Example 13 except that the powder and particles were not injected into the photosensitive drum 1, and the photosensitive drum 1 was mounted in the same process cartridge and printer to measure the sound. did. The results are shown in Table 3.

From the results shown in Table 3, it can be seen that the amount of sound increase Δ due to charging is 1 dB in the present invention, but Δ is 7 dB in the comparative example, and the effect is sufficiently obtained.

Experimental Examples 14 and 15 As shown in Table 3, tin oxide powder and water or titanium oxide powder and water were used as filling materials, and the photosensitive drum 1 was prepared in the same manner as in Experimental Example 13 except that the same process cartridge was used. ,
It was mounted on a printer and the sound was measured. The weight per volume of the photosensitive drum 1 is 1.42 when the filler is tin oxide powder and water.
g / cm ³ , 1.42 g / c for titanium oxide powder and water
m is ^3.

Experimental Example 16 Evaluations were made in the same manner as in Experimental Example 13 except that the laser beam printer which was an electrophotographic apparatus was modified so that the input pixel density was 600 dpi and the frequency of the applied AC voltage was 650 Hz. .

Comparative Example 6 The sound was measured by mounting it in the same process cartridge and printer as in Experimental Example 16 except that the filler was not inserted in the photosensitive drum 1.

Table 3 also shows these results. As can be seen from the above, in Comparative Example 6, the sound increase Δ due to the increase in the pixel density and the required frequency is also 10 dB.
(A) Increase, but in Experimental Examples 14 to 16 of the present invention, the amount of sound increase Δ due to charging is 1 to 2 dB (A), and the sound damping effect is sufficiently exhibited.

Experimental Example 17 The photosensitive drum 1 is the same as the experimental example 12 except for the filling, and the length of the substrate 11 is 346 mm. This was filled with aluminum powder and water enclosed in a tube, and the same as in Experimental Example 13, the drive transmission gear 13, the bearing flange 14
Were bonded with an adhesive to prepare an electrophotographic photosensitive drum 1. The total weight of the photosensitive drum 1 is 1.07 g.
/ Cm ³ .

As the electrophotographic apparatus, the plain paper copying machine "Type NP-2020" (modified by Canon) used in Experimental Example 12 was used. Sound was measured using the photosensitive drum 1 and the apparatus in the same manner as in Experimental Example 1. The results are shown in Table 3. From this result, it can be seen that the photosensitive drum 1 of Experimental Example 17 has a sufficient noise increase of Δ2 dB (A) due to charging, and is sufficiently silent.

[Fourth Embodiment] Next, a fourth embodiment of the present invention will be described. The configuration except the filling of the photosensitive drum 1 is the same as the previous embodiments, and the photosensitive drum 1 is filled with the granular material. As a method of filling the photosensitive drum 1 with the granular material, a method of directly injecting the granular material after connecting the bearing flange 14 and the like to at least one end of the base body 11,
Alternatively, a method in which a powdery material is previously sealed in a tubular resin-made package film 16 (see FIG. 10) or the like is inserted into a synthetic resin case before being inserted. The sealing method is also the same as the case of filling the liquid as described above. Any type of powder may be used as long as the weight of the photosensitive drum 1 when filled satisfies the conditions of the present invention, but in consideration of being used in an electrophotographic apparatus, flammability, Ignition materials, strong odor materials, toxic materials, corrosive materials, and easily magnetized materials are not preferable. Therefore, plastic powder, non-magnetic metal powder, ceramic powder and the like are preferable. If necessary, an additive or the like for preventing deterioration may be added to these powders.

It is important that the filling material is in close contact with the inner wall of the base 11 of the photosensitive drum 1. Therefore, when the powder or granules are directly injected, it is necessary to fill the base 11 so that the powder or granules do not flow. In addition, when inserting a product in which the powder or granular material is packaged in advance, the package film 16
Alternatively, it is necessary to bring the synthetic resin case into close contact with the inner wall of the base 11. As for the method of fixing the insert at this time, it may be fixed only by press fitting, or an adhesive or the like may be used together as an auxiliary means depending on the gap with the inner wall of the substrate, as in the case of filling the liquid. .

The removal of the packing material in the recycling of the fourth embodiment is the same as that of the second or third embodiment.

Next, an experimental example of the present invention will be described.

Experimental Example 18 The same photosensitive drum 1 as in Experimental Example 1 was used except for the filler.
A tube containing aluminum powder was filled in the photosensitive drum 1 in a base body 11, and then a drive transmission gear 13 and a bearing flange 14 made of a polycarbonate resin as illustrated in FIG. 1 were joined by an adhesive. The weight per total volume of the photosensitive drum 1 was 1.1 g / cm ³ .
Next, this photosensitive drum 1 was incorporated into a process cartridge similar to that of Experimental Example 1, and this was mounted in the laser beam printer used in Experimental Example 1, and the sound generated by charging was measured. The sound measuring method is the same as in the above experimental example.

Comparative Example 7 A photosensitive drum 1 was prepared in the same manner as in Experimental Example 18 except that the powdery material was not injected into the photosensitive drum 1, and the photosensitive drum 1 was mounted in the same process cartridge and printer and the sound was measured.
The results are shown in Table 4.

If the increase Δ in the sound due to charging is 4 dB (A) or less, the sound level is practically no problem including the auditory sense. From the results in Table 4, the increase Δ in the sound is compared. An example is 7 dB (A), which is a problem in practical use, but in Example 18 it is 1 dB (A), indicating that the effect of the present invention is sufficiently obtained.

Experimental Examples 19 and 20 As shown in Table 4, tin oxide powder or titanium oxide powder was used as the filling material, and a photosensitive drum was prepared in the same manner as in Experimental Example 18 except that it was mounted on the same process cartridge and printer. The sound was measured. The weight per volume of the photosensitive drum 1 is 1.4 g / cm ³ .

Experimental Example 21 Evaluations were made in the same manner as in Experimental Example 18 except that the laser beam printer which was an electrophotographic apparatus was modified so that the input pixel density was 600 dpi and the frequency of the applied AC voltage was 650 Hz. .

Comparative Example 8 The sound was measured by mounting the same on a process cartridge and a printer as in Experimental Example 21 except that the filler was not inserted in the photosensitive drum 1.

The results are also shown in Table 4. As can be seen from this, in the comparative example 8, the increase Δ of the sound due to the increase in the pixel density and the required frequency is also 10d.
Although B (A) is increased, the increase in sound is 1 to 2 dB (A) in Experimental Examples 19 to 21 of the present invention, and the sound damping effect is sufficiently exhibited.

Experimental Example 22 The photosensitive drum 1 is the same as the experimental example 12 except for the filler, and the length of the substrate 11 is 346 mm. This was filled with aluminum powder enclosed in a tube, and Experimental Example 1
In the same manner as in No. 8, the drive transmission gear 13 and the bearing flange 14 were joined by an adhesive to prepare the electrophotographic photosensitive drum 1.
The total weight of this photosensitive drum is 0.70 g / cm.
^{Was 3} .

As the electrophotographic apparatus, the plain paper copying machine "type NP-2020" (modified by Canon) used in Experimental Example 12 was used. Sound was measured using the photosensitive drum 1 and the apparatus in the same manner as in Experimental Example 1. As shown in Table 4, the sound increase Δ due to charging was 4 dB (A).

[Fifth Embodiment] A fifth embodiment is characterized in that a filler 50 having a coil spring-like shape shown in FIGS. 12 to 15 is inserted as means for imparting weight to the photosensitive drum 1. Further, according to the present invention, the manufacturing process of the electrophotographic photosensitive drum 1 is simplified by inserting the filler 50 having a coil spring-like shape.
It also achieves another purpose of providing recyclability. That is, in the spring-like filler 50 of the present invention, the manufacturing process is simple because the spring-like restoring force is utilized.
Also, it is extremely easy to remove, does not damage the base 11, and imparts high recyclability. That is, when the coil spring is expanded and contracted perpendicularly to its center axis, the apparent outer diameter becomes thicker when it is reduced and becomes thinner when it is expanded, so that the free outer diameter is selected to be slightly thicker than the inner diameter of the base body 11. For extension and fixing, the restoring force of the spring may be used without any other fixing means. Further, the fixing force and the packing density can be selected as appropriate depending on the spring constant, the number of turns of the coil, the wire diameter of the coil, the material and the like.

FIG. 12 shows the shape of the coil spring filling 50 used in the present invention, but the present invention is not limited to this. In FIG. 12, a coil spring filler 50 using a wire having a rectangular cross section is used. The outer peripheral surface of the coil spring filler 50 is required to be substantially in contact with the inner wall of the base 11 in order to absorb the vibration generated by the charging of the photosensitive drum 1. Therefore, a synthetic resin such as rubber, urethane or vinyl is required. It may be coated with a material.

As the material of the rigid body, any material may be used as long as the weight of the photosensitive drum 1 when it is inserted satisfies the conditions of the present invention and has a spring restoring force.
Metallic materials such as spring steel, chrome vanadium steel, chrome manganese steel, stainless steel, phosphor bronze, etc. as described in IS, and plastic materials such as FRP are suitable, and further, the density is 2.0 g / cm ³ or more. Preferably there is. This is because the higher the density, the higher the effect of absorbing sound vibrations, and the smaller the size for obtaining the necessary weight, so that the insertion is easier and the productivity is improved. It may be appropriately selected from these, considering various factors such as workability, productivity, and cost. The length of the coil spring filling 50 may be such that the weight of the coil spring filling 50 in the state of being inserted in the photosensitive drum 1 is the volume of the present invention. When the length of the coil spring filling 50 is shorter than the length of the base 11, it is effective to insert the filling 50 at the center of the base 11. That is, it is preferable that the coil spring filler 50 is inserted at a position such that the axial center thereof coincides with the axial center of the base 11 of the photosensitive drum 1. In addition, a plurality of coil spring fillers 50 may be used. In that case, it is effective to arrange the coil spring fillers 50 so as to be symmetrical in the length direction of the base 11. FIG. 14 shows a coil spring filler 50 using a wire having a circular cross section.
The configuration of the photosensitive drum 1 excluding the filling is the same as that of each of the above-described embodiments, and the process cartridge and the electrophotographic apparatus are also the same.

The disassembling of the fifth embodiment at the time of recycling is performed by disassembling the drive transmission gear 13 and the bearing flange 14 from the base body 11 and then applying a pulling force to both ends of the coil spring filler 50 in the axial direction by using a so-called puller. Fifty
And reduce the diameter.

Experimental Example 23 The same photosensitive layer 12 was laminated on the same substrate 11 as in Experimental Example 1.
The dimensions indicated by the reference numerals in FIG. 12 are center diameter A 26 mm, total length B 200 mm, wire thickness (radial dimension of wire) a6 m.
m, wire width (wire axial dimension) b6 mm, end coil end thickness c3 mm, total number of turns 16 m, material phosphor bronze, spring constant 1.3 kgf / mm
Was inserted into the substrate 11.

The coil spring filler 50 is loaded into the base body 11 by temporarily expanding the spring-like filler 50, inserting it with an apparent outer diameter smaller than the inner diameter of the base body 11, and then restoring and holding it in the base body 11. , Fixed. Further, a drive transmission gear 13 and a bearing flange 14 made of a polycarbonate resin as illustrated in FIG. 1 were joined to both ends of the photosensitive drum 1 with an adhesive to manufacture the electrophotographic photosensitive drum 1. The total weight of the photosensitive drum 1 is 1.6.
It was g / cm ³ .

Next, the photosensitive drum 1 was incorporated into a process cartridge similar to that of Experimental Example 1 having the structure as shown in FIG. 4, mounted in a laser beam printer, and the sound generated by charging was measured.

Comparative Example 9 A photosensitive drum 1 was prepared in the same manner as in Experimental Example 23 except that the filler was not inserted in the photosensitive drum 1.
The weight per unit volume was 0.40 g / cm ^3, and the same process cartridge and printer were mounted and the sound was measured. The results are shown in Table 5.

The increase Δ of the sound due to charging is 4 dB (A) or less and 1 dB (A) which is not a practical problem in Experimental Example 23.
Since the same increase Δ in Comparative Example 8 is 7 dB (A), it is understood that the effect of the present invention is sufficiently obtained.

Experimental Example 24 In FIG. 12, as a coil spring filler 50, material stainless steel, center diameter A26 mm, total length B200 mm, wire thickness a5 mm, wire width b3 mm, end coil end thickness c3 mm, total number of turns 14, spring constant 0.7 kgf. The photosensitive drum 1 was prepared in the same manner as in Experimental Example 23 using a coil spring of / mm, and was mounted in the same process cartridge and printer to measure sound. The weight per volume of the photosensitive drum 1 is 0.7
It is g / cm ³ .

Experimental Example 25 In FIG. 12, as a filler 50, material FRP, center diameter A26 mm, total length B200 mm, line thickness a8 mm, line width b
mm, end coil thickness c3 mm, total number of windings 20, spring constant 1.
A coil spring of 0 kgf / mm is used, and the others are Experimental Example 2
The photosensitive drum 1 was prepared in the same manner as in No. 3, and mounted on the same process cartridge and printer, and the sound was measured. The weight per volume of the photosensitive drum 1 is 1.1 g / cm ³ .

Experimental Example 26 In FIG. 14, as a filler 50, the material was phosphor bronze, the center diameter was A'30 mm, the total length was B'190 mm, and the wire diameter was d4 mm.
End turn thickness c'3 mm, total number of turns 14, spring constant 1.1 k
A photosensitive drum 1 was produced in the same manner as in Experimental Example 23 except that a coil spring of gf / mm was used, and the photosensitive drum 1 was mounted in the same process cartridge and printer and the sound was measured. The weight per volume of the photosensitive drum 1 is 0.9 g / cm ³ .

Experimental Example 27 In FIG. 14, as a filler 50, a material of stainless steel,
Center diameter A'27mm, total length B'190mm, wire diameter d6m
m, end coil thickness c3 mm, total number of windings 13, spring constant 1.9
A coil spring of kgf / mm is used, and the others are Experimental Example 23.
The photosensitive drum 1 was prepared in the same manner as in 1. and mounted on the same process cartridge and printer, and the sound was measured. The weight per volume of the photosensitive drum 1 is 1.3 g / cm ³ .

Experimental Example 28 Evaluations were made in the same manner as in Experimental Example 23, except that the laser beam printer which was an electrophotographic apparatus was modified so that the input pixel density was 600 dpi and the frequency of the applied AC voltage was 650 Hz.

Comparative Example 10 The materials and thickness of the substrate 11 of the photosensitive drum 1 are the same as those in Experimental Examples 23 to 2.
Same as No. 8, length was 346 mm. The sound was measured by mounting it on the same process cartridge and printer as in Experimental Example 28 except that the filler was not inserted in the photosensitive drum. The weight per volume of the photosensitive drum 1 is 0.4 g / cm ³ .

The results are also shown in Table 5. As can be seen from this, in Comparative Example 10, the increase Δ of the sound due to the increase in the pixel density and the required frequency is 8d.
B (A) is increased, but in Experimental Examples 24 to 28 of the present invention, the sound damping effect is sufficiently exhibited, and the increase Δ is 1 to 1
It is 4 dB (A).

Experimental Example 29 As the filler 50, material FRP, outer diameter A'25 mm, total length B'120 mm, wire diameter d10 mm, end-turn thickness C'4
mm, total number of windings 8 and spring constant 1.2 kgf / mm in FIG.
The two coil springs shown in are arranged symmetrically.
The weight per volume of the photosensitive drum 1 is 1.2 g / cm ³ . Otherwise, the sound was measured as in Experimental Example 28. Also by this, the amount of increase Δ of the sound due to charging is 3 dB (A), and the sound damping effect is sufficiently obtained.

[0100]

In the conventional method for filling a rigid body in a substrate, a method such as adhesion, press-fitting, caulking, or the like has been adopted for fixing the substrate and the filling material, but unless these methods are used for complete fixing. The original purpose, muffling, was not achieved.
These methods such as adhesion, press-fitting and caulking make it difficult to complicate the manufacturing process and further to recycle the substrate after removing the filler from the substrate.

In the first to fifth inventions of the present invention, since the filling material having the C-shaped cross section is used, its springiness restoring force can be utilized, the manufacturing process is simple, and it is very easy to remove it. Gives high recyclability without damaging the. That is, the packing of the present invention has a cylindrical or cylindrical C-shaped cross section perpendicular to the axial direction to reduce its outer diameter by using an external force, and then is inserted into the base body to remove the external force. It becomes possible to restore the outer diameter and fix it in the substrate, without any other fixing means. Further, as the fixing force and the packing density, appropriate values can be selected depending on the material, wall thickness, length and processing method of the packing of the present invention. This greatly contributes to speeding up and noise reduction of the electrophotographic apparatus using direct charging.

The sixth to fourteenth inventions of the present invention have the effect of damping vibrations due to electrification by a simple method of filling a substrate with a liquid or a liquid and a powder or granules, or a powder or granules. It is also excellent. Further, when a liquid is used, since the liquid flows in the substrate, there is a ripple effect that the temperature of the entire photosensitive drum can be made uniform.

In the fifteenth to nineteenth inventions of the present invention, the coil spring filling material is inserted into the base body, so that the same effects as the first to fifth inventions can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view of a photosensitive drum.

FIG. 2 is a sectional view of a photosensitive drum at right angles to an axis.

FIG. 3 is a schematic vertical sectional view of an image forming apparatus.

FIG. 4 is a vertical sectional view of a process cartridge.

FIG. 5 is a perspective view of a filling material according to the first embodiment.

FIG. 6 is a front view of the end surface of FIG.

FIG. 7 is a perspective view of a modified example of the filling material according to the first embodiment.

FIG. 8 is a front view of the end surface of FIG.

FIG. 9 is a cross-sectional view including a shaft center of a photosensitive drum according to a second exemplary embodiment.

FIG. 10 is a sectional view including a shaft center of a photosensitive drum of a modified example of the second embodiment.

FIG. 11 is a cross-sectional view of the photosensitive drum of Example 2 taken along a plane perpendicular to the axis.

FIG. 12 is a vertical cross-sectional view of the coil spring filling of Example 5.

FIG. 13 is a front view of the end surface of FIG.

FIG. 14 is a side view of another example of the fifth embodiment.

FIG. 15 is a front view of the end surface of FIG.

[Explanation of symbols]

 1 Photosensitive Drum 5 Charging Roller 11 Base 16 Package Film 24 Liquid 50 Filling Material

Front page continued (72) Inventor Hideki Anayama 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hideyuki Ainoya 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Junichi Kishi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Nobuyuki Hanami 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hidetoshi Hirano 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hiroshi Aoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Takao Soma 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (19)

[Claims] 1. A photosensitive layer provided on a cylindrical substrate,
An electrophotographic photosensitive drum which is formed by connecting a drive transmission member, a bearing member and the like to an end of the base, and which is directly charged by a contact charging member, and has a cylindrical or cylindrical shape in the base. An electrophotographic photosensitive drum characterized in that the weight with respect to the total volume of the electrophotographic photosensitive drum is set to 0.65 kg / cm ³ or more by inserting a filler having a C-shaped cross section perpendicular to the direction. 2. The filler having a C-shaped cross section perpendicular to the axial direction is inserted in such a position that the axial center of the filler coincides with the axial center of the base of the photosensitive drum. 1. The electrophotographic photosensitive drum described in 1. 3. The filling material having a C-shaped cross section perpendicular to the axial direction is contracted and stored in the base body, and is held and fixed to the base body only by the restoring force of the spring force. The electrophotographic photosensitive drum according to claim 2. 4. At least a photosensitive drum, a contact charging member,
An electrophotographic process cartridge provided with a developing means, wherein the photosensitive drum is the electrophotographic photosensitive drum according to any one of claims 1 to 3. 5. A photosensitive drum, a contact charging member,
An electrophotographic apparatus using an exposing unit, a developing unit, and a transferring unit, wherein the photosensitive drum is the electrophotographic photosensitive drum according to any one of claims 1 to 3. 6. A photosensitive layer provided on a cylindrical substrate,
In an electrophotographic photosensitive drum which is formed by connecting a drive transmission member, a bearing member and the like to an end of the base and is directly charged by a contact charging member, by filling the base with a liquid, The weight for the total volume is 0.
An electrophotographic photosensitive drum having a weight of 65 g / cm ³ or more. 7. A photosensitive drum, a contact charging member,
An electrophotographic process cartridge provided with a developing means, wherein the photosensitive drum is the electrophotographic photosensitive drum according to claim 6. 8. A photosensitive drum, a contact charging member,
An electrophotographic apparatus using an exposing means, a developing means, and a transferring means, wherein the photosensitive drum is the electrophotographic photosensitive drum according to claim 6. 9. A photosensitive layer provided on a cylindrical substrate,
In an electrophotographic photosensitive drum which is formed by connecting a drive transmission member, a bearing member and the like to the end portion of the base and is directly charged by a contact charging member, by filling the base with powder and granules and liquid, An electrophotographic photosensitive drum, characterized in that the weight of the entire photosensitive drum is 0.65 g / cm ³ or more. 10. An electrophotographic process cartridge including at least a photosensitive drum, a contact charging member, and a developing means, wherein the electrophotographic photosensitive drum according to claim 9 is used as the photosensitive drum. . 11. An electrophotographic apparatus comprising at least a photosensitive drum, a contact charging member, an exposing means, a developing means, and a transferring means, wherein the photosensitive drum is the electrophotographic photosensitive drum according to claim 9. Photographic equipment. 12. A photosensitive layer provided on a cylindrical substrate in an electrophotographic apparatus, and a drive transmission member, a bearing member and the like are coupled to an end portion of the substrate, and is directly charged by a contact charging member. In the electrophotographic photosensitive drum, the weight of the electrophotographic photosensitive drum with respect to the total volume of the electrophotographic photosensitive drum is set to 0.65 g / cm ³ or more by filling the base material with powder particles. 13. An electrophotographic process cartridge comprising at least a photosensitive drum, a contact charging member, and a developing means, wherein the photosensitive drum is the electrophotographic photosensitive drum according to claim 12. . 14. An electrophotographic apparatus using at least a photosensitive drum, a contact charging member, an exposing means, a developing means, and a transferring means, wherein the photosensitive drum is the electrophotographic photosensitive drum according to claim 12. apparatus. 15. An electrophotographic photosensitive drum, which comprises a photosensitive layer provided on a cylindrical substrate, and a drive transmission member, a bearing member, etc., which are joined to the end of the substrate, and which is directly charged by a contact charging member. An electrophotographic photosensitive drum characterized in that a weight having a total volume of the electrophotographic photosensitive drum is set to 0.65 g / cm ³ or more by inserting a filler having a coil spring-like shape into the base. 16. The electrophotographic photosensitive drum according to claim 15, wherein the center of the filler having the coil spring-like shape in the axial direction is aligned with the axial center of the base of the photosensitive drum. . 17. The electrophotographic photosensitive drum according to claim 15, wherein the filler having the coil spring-like shape is held and fixed to the base body only by its springy restoring force. 18. An electrophotographic process cartridge comprising at least a photosensitive drum, a contact charging member, and a developing means, wherein the photosensitive drum is any one of claims 15 to 17.
A process cartridge for electrophotography, comprising the electrophotographic photosensitive drum described in 1. 19. An electrophotographic apparatus comprising at least a photosensitive drum, a contact charging member, an exposing means, a developing means, and a transferring means, wherein the photosensitive drum is the electrophotographic photosensitive drum according to any one of claims 15 to 17. An electrophotographic device characterized by being used.