JPH08146637A - Electrophotographic photoreceptor drum with built-in filler for preventing vibration and its production - Google Patents

Abstract

PURPOSE: To provide an electrophotographic photoreceptor drum which does not generates vibration sound and to provide its production method. CONSTITUTION: When an electrophotographic photosensitive drum having a photosensitive layer on a hollow cylindrical base body 1 is produced, aluminum columnar fillers 2 to prevent vibration are fixed to the inside of the hollow cylindrical base body 1 with an epoxy resin adhesive layer 3. The obtd. drum generates almost no abnormal sound when used. Since the photoreceptor drum causes no dimensional change, a high quality image print can be obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive drum capable of suppressing or preventing the generation of vibration noise during use and a method for manufacturing the same.

[0002]

2. Description of the Related Art Photosensitive drums used in electrophotographic devices are
Generally, it is manufactured by applying a photosensitive layer or the like on the surface of a metal hollow cylindrical substrate such as aluminum. Such a photosensitive drum is used in an electrophotographic copying machine or a laser printer, but various vibration sounds may be generated from the photosensitive drum depending on usage conditions. For example, Japanese Laid-Open Patent Publication No. 2-1186
No. 84 and JP-A-3-105348 disclose that
It is described that a squeak noise is generated due to the contact between the photosensitive drum and the cleaning blade.

[0003]

In all of the above-mentioned prior arts, as a means for preventing the generation of sound, some kind of anti-vibration material is inserted and fixed inside the hollow cylindrical substrate of the photosensitive drum. There is. However, if the filler, which is an anti-vibration material, is carelessly inserted and fixed, the dimensional accuracy of the hollow cylindrical substrate may deteriorate. That is, since the hollow cylindrical substrate of the photosensitive drum is usually formed of a thin cylinder made of aluminum, its mechanical strength is weak, and if there is a process of expansion or contraction when the filler is inserted, the hollow cylindrical substrate will be Deforms easily. SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art, and to provide a photosensitive drum in which a hollow cylindrical base body is not deformed and has a built-in filling body for preventing vibration during use, and a manufacturing method thereof.

[0004]

In order to achieve the above object, the inventors of the present invention have conducted extensive studies and, as a result, inserted a vibration preventing packing (hereinafter referred to as a packing) into a hollow cylindrical substrate of a photosensitive drum. When an epoxy resin adhesive was used as an adhesive for fixing, it was found that the adhesive did not expand or contract during curing, and the present invention was completed.

That is, the photosensitive drum for electrophotography of the present invention has a photosensitive layer on the surface of a hollow cylindrical substrate, and a filler is built in and fixed in the hollow cylindrical substrate via an epoxy resin adhesive layer. It is characterized by Further, the method for producing a photosensitive drum for electrophotography of the present invention comprises applying an epoxy resin adhesive onto the inner surface of the hollow cylindrical substrate of the electrophotographic photosensitive drum having a photosensitive layer formed on the surface of the hollow cylindrical substrate, and then, A vibration-proof filling body having an outer diameter slightly smaller than the inner diameter of the hollow cylindrical substrate is inserted into and fixed inside.

The present invention will be described with reference to the drawings.
FIG. 1 shows a preparatory step for manufacturing the photosensitive drum. A small amount of epoxy resin adhesive 3 is attached inside the hollow cylindrical substrate 1 of the photosensitive drum. A cylindrical body made of aluminum is used as the filling body 2, and it is effective to taper the insertion side end so that the filling body 2 can be easily inserted into the hollow cylindrical substrate of the photosensitive drum. Also, the outer diameter of the filling body
It is desirable that the inner diameter of the hollow cylindrical substrate is 10 to 50 μm smaller. The length of the packing is 10 times that of the hollow substrate.
-30% is preferable.

FIG. 2 shows a state in which the filling body is inserted and fixed, and the epoxy resin adhesive 3 has entered the gap between the hollow cylindrical substrate 1 and the filling body 2. In this state, the epoxy resin adhesive is hardened by leaving it at that temperature for about one day at room temperature, for several hours if heated to about 50 ° C., and the filler is hollowed through the epoxy resin adhesive layer. It is firmly adhered to the cylindrical substrate.

Any known epoxy resin adhesive can be used in the present invention. Regarding epoxy resins, the types and characteristics are widely introduced in the literature (for example, "Plastic Materials Course (1) Epoxy Resin" published by Nikkan Kogyo Shimbun on May 30, 1969), and are also widely used as adhesives. Since it is commercially available, it may be used.

It is also effective to fill the epoxy resin with a filler in order to improve the adhesive strength and mechanical properties. Examples of the filler include powders of inorganic materials such as silica, mica, calcium carbonate, calcium sulfate, kaolin and talc, and powders of metal materials such as aluminum. When an epoxy resin adhesive containing a filler is used, the viscosity of the adhesive increases and the filler prevents the filler from flowing, so that the filler moves inside the hollow cylindrical substrate before the adhesive cures. There is also an effect that it is not stabilized and is stabilized at a predetermined position.

[0010]

The function of the present invention will be described. The epoxy resin adhesive used in the present invention is widely used as an adhesive, and is characterized by the characteristic that the volume does not change during curing. Therefore, in the case of the present invention, since the filler is used as an adhesive for fixing the inside of the hollow cylindrical substrate of the photosensitive drum, there is no volume change due to the adhesive when the adhesive is cured, and the substrate is deformed. Disappears.

[0011]

EXAMPLES Examples of the present invention will be described, but the present invention is not limited thereto. Example 1 An aluminum pipe having a thickness of 1.25 mm, a diameter of 30 mmφ and a length of 253 mm was prepared. After roughening this surface by honing treatment, nylon resin (trade name: CM
8000, manufactured by Toray Industries, Inc.) was used to form an undercoat layer having a film thickness of 1 μm. An 18 μm-thickness charge transport layer made of X-type phthalocyanine and polyvinyl butyral resin was formed on this to form an organic photosensitive drum. Inside the aluminum pipe of the obtained photosensitive drum, an aluminum filler having a size of 27.4 mmφ × 50 mm was inserted. As a method, a main agent of an epoxy resin adhesive (trade name: EP007, manufactured by Cemedine Co., Ltd.) and a curing agent are mixed, a small amount of the mixture is applied to the inside of an aluminum pipe forming a photosensitive drum, and then a filler is inserted. Then, it was fixed at the center of the aluminum pipe. In this state, the photosensitive drum was left to stand sideways and left for 1 day to cure the adhesive to fix the filling body.

The charging of the photosensitive drum containing the thus-prepared filling body was measured by a charging roll method. The photosensitive drum without a filling body has a sound pressure of -46 dB,
While a slight jarring sound was produced, the photosensitive drum of the present invention containing the filler had a sound pressure of -60 dB (the smaller the value, the smaller the sound), and the sound was hardly heard. The beeping sound is synchronized with the turn-on of the charging power source and is presumed to be resonance due to the oscillating electric field of the charging roll.

Comparative Examples 1 and 2 The following adhesives were used in place of the above epoxy resin as the adhesive for fixing the filler. 1. Acrylic adhesive (trade name: Polysic, Sanyo Kasei Co., Ltd.) 2. Synthetic rubber adhesive (trade name: Bond G7, manufactured by Konishi) After inserting and adhering the filler, the outer diameter of the filler insertion portion of the photosensitive drum was measured with a laser micrometer.
The results shown in Table 1 were obtained.

[0014]

[Table 1] In each of the above comparative examples, it is considered that the volume of the adhesive contracted due to the evaporation of the solvent at the time of adhesion, resulting in a reduction in the outer diameter of the photosensitive drum. Also in the output image of the printer, the photosensitive drum of each comparative example had uneven density at the insertion position of the filling body.

Example 2 An epoxy resin (trade name: E250, manufactured by Konishi Co., Ltd.) filled with a filler (silica, talc, calcium carbonate, kaolin) was used as an adhesive for the filler. In this case, there is an advantage that the filling body does not move and the drum storage space is small even if the photosensitive drum is left standing vertically until the adhesive is cured. There was no change in the outer diameter after bonding, and no abnormal noise was generated when the photosensitive drum was used.

[0016]

Since the present invention is constructed as described above, the volume change due to the adhesive does not occur when the filler is inserted and fixed in the hollow cylindrical substrate of the photosensitive drum. The deformation of the base is prevented. Further, since the epoxy resin adhesive does not contain a solvent, in the present invention, there is no fear of the solvent adversely affecting the photosensitive layer,
It has advantages over other adhesives that use solvents, and is extremely advantageous for industrial benefit.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a preparatory process for assembling a photosensitive drum of the present invention.

FIG. 2 is a sectional view showing an outline of a photosensitive drum of the present invention.

[Explanation of symbols]

 1 ... Hollow cylindrical substrate 2 ... Filler 3 ... Epoxy resin adhesive

Claims (6)

[Claims] 1. An electrophotographic photosensitive drum having a photosensitive layer on the surface of a hollow cylindrical substrate, wherein an antivibration filler is internally fixed inside the hollow cylindrical substrate via an epoxy resin adhesive layer. Characteristic photosensitive drum for electrophotography. 2. The photosensitive drum for electrophotography according to claim 1, wherein the vibration preventive filling body is a cylindrical body made of aluminum. 3. The electrophotographic photosensitive drum according to claim 1, wherein the epoxy resin adhesive layer contains a filler. 4. An epoxy resin adhesive is applied on the inner surface of the hollow cylindrical substrate of an electrophotographic photosensitive drum having a photosensitive layer formed on the surface of the hollow cylindrical substrate, and then an outer surface slightly smaller than the inner diameter of the hollow cylindrical substrate. A method for manufacturing a photosensitive drum for electrophotography, characterized in that a vibration-proof filling body having a diameter is inserted and fixed therein. 5. The method for manufacturing a photosensitive drum for electrophotography according to claim 4, wherein the insertion tip of the vibration prevention filler has a slight taper. 6. The method for producing a photosensitive drum for electrophotography according to claim 4, wherein an epoxy resin adhesive containing a filler is used.