JP2002311618A - Substrate for photosensitive drum and photosensitive drum - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive drum which is excellent in dimensional accuracy and is capable of forming images having excellent image quality free of unevenness and a substrate for the photosensitive drum adequate for this photosensitive drum. SOLUTION: This substrate for the photosensitive drum contains a resin, is rotatable and is <=80 μm in the deflection of rotation. The form that the deflection of rotation is <=60 μm, the form that the resin contains a polyamide resin, the form that the resin contains at least either of nylon 66 and nylon 6, the form that the resin contains at least any among polypropylene, polyphenylene ether and polyphenylene sulfide, the form that the resin contains inorganic fillers, etc., are more preferable. This photosensitive drum has at least a photosensitive layer on the substrate for the photosensitive drum.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a photosensitive drum used in an electrophotographic apparatus or an electrostatic recording apparatus, and a photosensitive drum base suitable for the photosensitive drum.

[0002]

2. Description of the Related Art In an electrostatic recording process in a copying machine, a facsimile, a printer, or the like, first, the surface of a photosensitive drum is uniformly charged, and an image is projected from an optical system onto the surface of the photosensitive drum and light is applied to the portion. Forming an electrostatic latent image by erasing the charge of the toner, and then supplying toner to the electrostatic latent image to form a toner image by electrostatic adhesion of the toner, and forming the toner image on paper, OHP, photographic paper, etc. The image is transferred to a recording medium to form an image.

[0003] In a photosensitive drum used in such an electrostatic recording process, a drum base is conventionally made of an aluminum alloy in a cylindrical shape because of its relatively light weight, excellent machinability, and good conductivity. -A drum base processed into a cylindrical shape is used. In recent years, as an alternative to the aluminum alloy drum base, a resin such as a thermoplastic resin, a drum base processed from a composite material based on the resin, and the like have been used.

Here, in the electrostatic recording process, since an image is formed on a recording medium by rotating a cylindrical / columnar drum base, the drum base is required to have excellent dimensional accuracy and the like. Have been.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to meet the above-mentioned various demands in the prior art and achieve the following objects. That is, an object of the present invention is to provide a photosensitive drum which is capable of forming an image having excellent dimensional accuracy and excellent image quality without unevenness, and a photosensitive drum base suitable for the photosensitive drum.

[0006]

Means for solving the above problems are as follows. That is, <1> a photosensitive drum substrate which contains a resin, is rotatable, and has a rotational runout of 80 μm or less. <2> The photosensitive drum substrate according to <1>, wherein the rotational runout is 60 μm or less. <3> The resin according to <1>, wherein the resin contains a polyamide resin.
> Or <2>. <4> The photosensitive drum substrate according to any one of <1> to <3>, wherein the resin contains at least one of nylon 66 and nylon 6. <5> The photosensitive drum substrate according to <3> or <4>, wherein the resin contains at least one of polypropylene, polyphenylene ether, and polyphenylene sulfide. <6> The photosensitive drum substrate according to any one of <1> to <5>, further including an inorganic filler. <7> A photosensitive drum having at least a photosensitive layer on the photosensitive drum substrate according to any one of <1> to <6>.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. [Substrate for Photosensitive Drum] The substrate for photosensitive drum of the present invention contains a resin and, if necessary, other components.

It is necessary that the photosensitive drum substrate is rotatable and has a rotational deflection of 80 μm or less, preferably 60 μm or less. If the rotational shake exceeds 80 μm, the dimensional accuracy is poor, and an image having excellent image quality and no unevenness cannot be formed.

The rotational vibration is measured using a rotational vibration measuring device (laser scan micro) at a speed of three revolutions per second by rotating the photosensitive drum base, and performing 256 measurements during the three revolutions. The results were averaged, and the rotational runout of the central portion of the photosensitive drum substrate was measured.

[0010] As the photosensitive drum substrate, weight reduction,
It is necessary to contain the resin in terms of reduction of driving power and the like. As the resin, a conductive resin composition is preferable,
The resin base material constituting the conductive resin composition is not particularly limited, but is preferably a thermoplastic resin. As the thermoplastic resin, all known resin materials conventionally used for a photosensitive drum substrate are suitably mentioned, and in particular, have a good surface smoothness for forming a photosensitive layer, and Polyamide-based resins such as various nylons are preferable in terms of excellent chemical resistance and mechanical strength. Examples of the polyamide resin include nylon 11, nylon 12, nylon 4
6, nylon 6, nylon 66, nylon MXD6, nylon 610, nylon 612, nylon 1212, and copolymers thereof. These may be used alone or in combination of two or more. Among these, nylon 6 and nylon 66 are preferred because they are excellent in moldability and can be molded at low cost.

It is preferable to use a non-hygroscopic resin together with the polyamide resin or the like in the photosensitive drum substrate in order to suppress a dimensional change due to moisture absorption. Examples of the non-hygroscopic resin include polypropylene, polyphenylene ether, polyphenylene sulfide, and the like. It is preferable that these non-hygroscopic resins are appropriately selected in consideration of the compatibility with the polyamide resin and the like.

In general, the conductive resin composition is obtained by adding a conductive agent to the resin base material to impart conductivity. The conductive agent is not particularly limited as long as it can be uniformly and suitably dispersed in the resin substrate, and examples thereof include carbon black, graphite, aluminum, copper, metal powder such as nickel, and conductive glass powder. Particularly, carbon black is preferable. The content of the conductive agent in the conductive resin composition is not particularly limited;
% By weight, more preferably 5 to 20% by weight. Further, by including the conductive agent, the surface resistance of the substrate is preferably set to 10 ⁴ Ω / □ (ohm / square) or less, more preferably 10 ² Ω / □ or less.

The photosensitive drum substrate may optionally contain an inorganic filler such as various fibers for the purpose of reinforcing and increasing the amount. Examples of the inorganic filler include conductive fibers such as carbon fibers, conductive whiskers, and conductive glass fibers, and non-conductive fibers such as whiskers and glass fibers. Since the conductive fiber can also act as a conductive agent, the amount of the conductive agent such as the carbon black can be reduced by using the conductive fiber.

The amount of the inorganic filler is not particularly limited, and is appropriately selected depending on the kind of the inorganic filler, the length and the diameter of the fiber, and the like. 1 to 30% by weight is preferable, 5 to 25% by weight is more preferable, and 10 to 25% by weight is further preferable.

The conductive resin composition may include, if desired, polytetrafluoroethylene (PTFE), silicone, molybdenum disulfide (Mo), in addition to the inorganic filler.
S ₂ ), known additives such as various metal soaps can be added in appropriate amounts. The conductive agent, the inorganic filler, and the like may be subjected to a surface treatment using a silane coupling agent, a titanate coupling agent, or the like that is generally used.

The shape of the substrate for the photosensitive drum is preferably a cylindrical shape, a cylindrical shape, or the like in that an image can be easily formed on a recording medium by rotation. The method for molding the substrate is not particularly limited, and examples thereof include an injection molding method and an extrusion molding method, and the injection molding method is particularly preferable. Molding conditions such as molding temperature and injection pressure are appropriately selected according to the type of the resin component constituting the base.

[Photosensitive Drum] The photosensitive drum of the present invention has a photosensitive layer on the photosensitive drum substrate of the present invention, and has other layers as necessary.

-Photosensitive Layer- The photosensitive layer preferably has at least a charge generation layer and a charge transport layer.

--Charge Generating Layer-- The charge generating layer preferably contains a charge generating compound and a binder resin.

The charge generating compound is not particularly limited, and may be appropriately selected from known compounds used in the charge generating layer of a photoreceptor.
Organic conductive compounds and the like can be mentioned. Among these,
Compounds and the like having high charge generating ability are preferred. The binder resin is not particularly limited, and is appropriately selected from known resins conventionally used for a charge generation layer of a photoconductor. The charge generation layer can be formed by a known method such as coating and vapor deposition.

--Charge Transport Layer-- The charge transport layer preferably has a non-uniform charge transport layer and a uniform charge transport layer.

The heterogeneous charge transport layer is not particularly limited, but is preferably a particle-dispersion type heterogeneous charge transport layer, a phase separation type heterogeneous charge transport layer, or the like. The heterogeneous charge transport layer,
The material to be contained in the heterogeneous charge transport layer, such as a polymer material, can be dispersed in a solvent and formed by a known method such as coating.

The uniform charge transporting layer is not particularly limited, but preferably contains a polymer compound having high charge transporting ability and excellent film-forming properties. The uniform charge transport layer can be formed by dispersing a material to be contained in the uniform charge transport layer, such as the polymer material, in a solvent, and by a known method such as coating.

-Other Layers- Examples of the other layers include an undercoat layer and a protective layer.

[0025]

The present invention will be described in more detail with reference to the following examples and comparative examples. However, the present invention is not limited to the following examples.

(Examples 1 to 3 and Comparative Examples 1 and 2) Substrates for photosensitive drums having the component mixing ratios shown in Table 1 were prepared (cylindrical, dimensions: 24 mm (φ) × 260 mm (Examples 1 and 3)
After Comparative Examples 1 and 2) and 30 mm (φ) × 260 mm (Example 2)), the rotational deflection of the photosensitive drum substrate was measured and evaluated by the following evaluation method. Table 1 shows the results.

<Method of Evaluating Rotational Vibration> Using a rotational vibration measuring device (laser scan micro), the photosensitive drum substrate was rotated at a speed of 3 rotations per second, and 256 measurements were performed during the 3 rotations. The results were averaged, and the rotational runout at the center of the substrate was measured.

Thereafter, a thickness of 3 mm is applied to the photosensitive drum substrate.
A photosensitive layer having a thickness of 0 μm was formed to produce a photosensitive drum, and image characteristics were evaluated by the following evaluation methods. <Method for evaluating image characteristics> The photosensitive drum was mounted on a laser shot printer, an image was formed, and the image quality was visually evaluated. Table 1 shows the results.

[0029]

[Table 1]

In Table 1, "PA66" is nylon 66 ("UBE nylon" manufactured by Ube Industries, Ltd.),
"PA6" is made of nylon 6 ("UBE" manufactured by Ube Industries, Ltd.)
Nylon ”) and“ PPS ”are polyphenylene sulfide (“ Fortron ”manufactured by Polyplastics),“ C
/ B "is carbon black (" Ketjen Black "manufactured by Lion Corporation), and" Whisker "is potassium titanate whisker (" Tismo "manufactured by Otsuka Chemical Co., Ltd.).

From Examples and Comparative Examples, in Examples 1 to 3,
It can be seen that the value of the rotational shake is small and the image characteristics are good.

[0032]

According to the present invention, it is possible to provide a photosensitive drum capable of forming an image having excellent dimensional accuracy and excellent image quality without unevenness, and a photosensitive drum base suitable for the photosensitive drum.

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Claims (7)

[Claims] 1. A photosensitive drum base comprising a resin, rotatable and having a rotational runout of 80 μm or less. 2. The method according to claim 1, wherein the rotational runout is 60 μm or less.
3. The substrate for a photosensitive drum according to item 1. 3. The photosensitive drum substrate according to claim 1, wherein the resin contains a polyamide resin. 4. The substrate for a photosensitive drum according to claim 1, wherein the resin contains at least one of nylon 66 and nylon 6. 5. The photosensitive drum substrate according to claim 3, wherein the resin contains at least one of polypropylene, polyphenylene ether and polyphenylene sulfide. 6. The photosensitive drum substrate according to claim 1, further comprising an inorganic filler. 7. A photosensitive drum comprising at least a photosensitive layer on the photosensitive drum substrate according to claim 1. Description: