JP2002049278A - Electrophotographic photoreceptor process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain long-term reliability for bonding between a photoreceptor and a flange. SOLUTION: The electrophotographic photoreceptor for a process cartridge has a photosensitive drum, having a photosensitive layer containing a photoconductive material formed around a cylindrical conductive substrate and has a gear flange, which is adhered and fitted to the open end of the drum to support the center axis of the drum and to transmit external rotation driving force to the photosensitive drum. In this photoreceptor, the gear flange essentially comprises polycarbonate resin and contains polyethylene terephthalate resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member having a resin gear flange for supporting a central shaft passing through a photosensitive drum used in a process cartridge.

[0002]

2. Description of the Related Art An electrophotographic photoreceptor comprises a photosensitive drum having a photosensitive layer on the outer peripheral surface of a conductive substrate and flanges or geared flanges connected to both ends. This electrophotographic photoreceptor is mounted on a process cartridge,
It is installed in electrophotographic applications such as printers and facsimile machines.

[0003] A process cartridge is provided with a charging member (including static elimination) for applying a voltage and a member necessary for an electrophotographic process such as development and cleaning arranged around the electrophotographic photosensitive member together with the photosensitive member. The cartridge is housed in a cartridge and is detachably mounted on an electrophotographic application device, and performs a central function of image formation.

An electrophotographic application apparatus equipped with a process cartridge forms a latent image by performing exposure corresponding to image information on an electrophotographic photosensitive member uniformly charged by a charging process. The latent image is developed using a toner by a developing process to form a toner image. The toner image formed on the photoconductor is transferred to paper by a transfer process to form an image.

Conventionally, in an electrophotographic application apparatus using an electrophotographic process, a cartridge integrally storing an electrophotographic photosensitive member and an electrophotographic process disposed around the photosensitive member can be attached to and detached from the apparatus. The process cartridge system attached to the printer is widely used. According to this process cartridge, there is an advantage that maintenance of the apparatus is very simple because maintenance of the apparatus is almost unnecessary.

In a process cartridge, an electrophotographic photosensitive member performs an electrophotographic process by rotating by receiving a rotational driving force from an apparatus. A gear is provided on the flange for transmitting the driving force, and is connected to the open end of the photosensitive drum.

When the flange connected to the electrophotographic photosensitive member falls off the photosensitive member, the rotation of the electrophotographic photosensitive member stops, which causes a serious accident that the function of the apparatus stops. Ensuring reliability is an important technical issue.

For this purpose, various improvements have been proposed for flanges from various viewpoints.

For example, Japanese Patent Application Laid-Open No. 11-30931 discloses an invention in which a flange is formed from a composite resin material containing polycarbonate, polytetrafluoroethylene and glass. However, the invention described herein is limited to an electrophotographic photosensitive member that does not use an adhesive in order to facilitate recycling of an image forming member whose life has expired (corresponding to the electrophotographic photosensitive member of the present invention).

Japanese Patent Application Laid-Open No. Hei 10-18709 discloses that as a material of a drum flange, polyacetal, polycarbonate containing polytetrafluoroethylene, polyamide,
It is disclosed that a resin such as polyethylene is employed. However, the fitting of the flange to the photoreceptor is press-fitting, and furthermore, the connection of the end of the drum to the flange recess by bending is shown. The bonding using an adhesive is only a comparative example in the case of a polyacetal resin flange using an instant adhesive.

However, adaptation to high-speed laser beam printers and copiers and their use in various parts of the world, various ambient environments, and various use conditions under climatic conditions, with high reliability, There has not yet been obtained a bonding method that sufficiently satisfies the production cost. An adhesive having a high adhesive strength can be selected by selecting an adhesive material. However, an adhesive which meets all of the above conditions due to poor moldability or high material cost has not been obtained.

[0012]

In view of the above, the present invention has a good balance in terms of good adhesion to an adhesive, good moldability of resin, and low material cost. An object of the present invention is to provide an electrophotographic photosensitive member for a process cartridge, which can ensure long-term reliability in coupling a photosensitive member and a flange by employing a resin material.

[0013]

According to the present invention, it is an object of the present invention to provide a photosensitive drum in which a photosensitive layer containing a photoconductive material is formed on an outer peripheral surface of a cylindrical conductive substrate, and a center of the drum. A photoreceptor having a gear flange that is adhesively fitted to an open end thereof for supporting the shaft and transmitting an external rotational driving force to the photoconductive drum, wherein the gear flange is mainly composed of a polycarbonate resin, and is made of polyethylene terephthalate. This is achieved by forming an electrophotographic photosensitive member for a process cartridge containing a resin.

In the electrophotographic photosensitive member for a process cartridge, the weight ratio of the polyethylene terephthalate resin to the polycarbonate resin is 10 to 20%.
It is preferable that

Further, a photosensitive drum in which a photosensitive layer containing a photoconductive material is formed on the outer peripheral surface of a cylindrical conductive substrate, a support for a central shaft penetrating the drum, and an external rotational driving force. An electrophotographic photoreceptor for a process cartridge, comprising: a polycarbonate resin as a main component, and a polyphenylene sulfide resin, wherein the photoreceptor includes a gear flange that is adhesively fitted to an opening end thereof for receiving and transmitting the photoreceptor to a photosensitive drum. It is also achieved by:

Further, the weight ratio of the polyphenylene sulfide resin to the polycarbonate resin is 10 to
Preferably, it is 20%.

It is desirable that a gear flange fitted to the opening end of the photosensitive drum be bonded with a cyanoacrylate adhesive.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of an electrophotographic photosensitive member for a process cartridge according to the present invention will be described in detail with reference to the drawings.

The present invention is not limited to the embodiments described below.

A subbing layer, a photosensitive layer including a charge generation layer and a charge transport layer are formed on the outer peripheral surface of a drum-shaped substrate having an outer diameter of 30 mmφ and a length of 254 mm made of JIS 6000 aluminum alloy by dip coating in this order. As a material of the charge generation layer, a coating film in which titanyl phthalocyanine, which is a well-known photo charge generation material, is dispersed in a polyvinyl butyral resin is used.

As the material of the charge transport layer, a coating film obtained by dissolving hydrazone, which is a well-known charge transport material, in a polycarbonate resin is used. In the present invention, the material of the substrate and the photosensitive layer may be any material that satisfies the required characteristics of the photoreceptor, so other materials may be used, and the coating method is well known. Instead of the coating method, another method may be used. Photosensitive drum 1 comprising drum-shaped substrate 2 and photosensitive layer 3
As shown in the perspective view of FIG. 1, an adhesive 6 is applied by a discharge from a dispenser 7 in order to secure the connection with the gear flange 5 fitted inside the open end 4 thereof.

The gear flange 5 is fitted with the earth plate 8 side facing the photosensitive drum 1 side. The gear flange 5 is formed by injection molding a mixture of a polycarbonate resin as a main component and a polyphenylene sulfide resin or a polyethylene terephthalate resin.

(Experimental Example 1) Four kinds of gear flanges 5 composed of 5, 10, 20, and 25% by weight of a resin as a mixing ratio of a polyphenylene sulfide resin (PPS) to a polycarbonate resin (PC), and a polycarbonate resin and a polyphenylene sulfide. 300 gear flanges each made of a single resin are prepared, and a cyanoacrylate adhesive 6 (Loctite 403 manufactured by Nippon Loctite) is provided inside the opening end 4 of the photosensitive drum 1.
Were applied in the same amounts, and the gear flanges 5 were fitted and bonded. When the curing time after bonding each gear flange was 10 minutes, 30 minutes, 1 hour, 3 hours, and 8 hours, the maximum rotation torque of each gear flange was measured. The strength required to ensure long-term reliability of the flange connection is 3.8 N · m or more. As an experimental result, an average maximum rotation torque value for every ten gear flanges is shown.

[0024]

[Table 1]

(Experimental Example 2) Four kinds of gear flanges 5 composed of 5, 10, 20, and 25% by weight of a resin, a polycarbonate resin and a polyethylene terephthalate were used as a mixing ratio of a polyethylene terephthalate resin (PET) to a polycarbonate resin (PC). 300 gear flanges each made of a single resin are prepared, and a cyanoacrylate adhesive 6 (Loctite 403 manufactured by Nippon Loctite) is provided inside the opening end 4 of the photosensitive drum 1.
Were applied in the same amount, and the gear flanges 5 were fitted and bonded. For each gear flange when the curing time after bonding each gear flange was 10 minutes, 30 minutes, 1 hour, 3 hours, and 8 hours. The maximum rotation torque was measured. The strength required to ensure long-term reliability of the flange connection is 3.8 N · m or more. As an experimental result, an average maximum rotation torque value for every ten gear flanges is shown.

[0026]

[Table 2]

From the results shown in Tables 1 and 2, as the resin for the gear flange, a mixed resin in which the mixing ratio of each of the polyphenylene sulfide resin (PPS) and the polyethylene terephthalate resin (PET) to the polycarbonate resin (PC) is 10 to 20% by weight is shown. When used, the required curing time varies depending on the mixing ratio, but it can be seen that the maximum rotational torque of 3.8 Nm or more can be obtained for the connection.

[0028]

According to the present invention, a photosensitive drum in which a photosensitive layer containing a photoconductive material is formed on the outer peripheral surface of a cylindrical conductive substrate, a support for the center axis of the drum, and an external rotation drive A photoreceptor having a gear flange adhesively fitted to an opening end thereof for receiving a force and transmitting the force to a photosensitive drum, wherein the gear flange is made of a polycarbonate resin as a main component and contains a polyethylene terephthalate resin or a polyphenylene sulfide resin for a process cartridge. Since the electrophotographic photoreceptor is used, it is possible to obtain a well-balanced resin material in terms of good adhesion to the adhesive, good resin moldability, and low material cost. An electrophotographic photoreceptor for a process cartridge which can ensure long-term reliability in the bonding of the process cartridges.

[Brief description of the drawings]

FIG. 1 is a perspective view of a process cartridge electrophotographic photosensitive member according to an embodiment of the present invention before being combined.

[Explanation of symbols]

 1: photosensitive drum 2: drum-shaped substrate 3: photosensitive layer 4: open end 5: gear flange 6: adhesive 7: dispenser 8: ground plate

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) C08L 67:02) C08L 67:02) (C08L 69/00 (C08L 69/00 81:02) 81:02 )

Claims (5)

[Claims] 1. A photosensitive drum having a photosensitive layer containing a photoconductive material formed on an outer peripheral surface of a cylindrical conductive substrate, and a photosensitive drum for supporting a central axis of the drum and receiving an external rotational driving force. An electrophotographic photoreceptor for a process cartridge, comprising: a gear flange adhesively fitted to an open end thereof for transmission to a process cartridge, wherein the gear flange is mainly composed of a polycarbonate resin and contains a polyethylene terephthalate resin. Electrophotographic photoreceptor. 2. An electrophotographic photosensitive member for a process cartridge according to claim 1, wherein the weight ratio of the polyethylene terephthalate resin to the polycarbonate resin is 10 to 20%. 3. A photosensitive drum in which a photosensitive layer containing a photoconductive material is formed on an outer peripheral surface of a cylindrical conductive substrate, and a photosensitive drum for supporting a central axis of the drum and receiving an external rotational driving force. An electrophotographic photosensitive member for a process cartridge, comprising: a gear flange adhesively fitted to an open end thereof for transmitting the gear to the process cartridge, wherein the gear flange is mainly composed of a polycarbonate resin and contains a polyphenylene sulfide resin. Electrophotographic photoreceptor. 4. The electrophotographic photosensitive member for a process cartridge according to claim 3, wherein the weight ratio of the polyphenylene sulfide resin to the polycarbonate resin is 10 to 20%. 5. The electrophotographic photosensitive member for a process cartridge according to claim 1, wherein a gear flange fitted to an opening end of the photosensitive drum is bonded with a cyanoacrylate adhesive. body.