JPS5886550A - Drum-shaped image retaining body member - Google Patents

Abstract

PURPOSE:To obtain a lightweight drum-shaped image retaining body for electrostatic recording without requiring finish working by using an endless belt of a nonmagnetic metal having 0.1-2mm. thickness manufactured by an electroforming method as a drum-shaped substrate and by forming an image retaining layer on the substrate. CONSTITUTION:A drum-shaped substrate 21 is formed with an endless belt of a nonmagnetic metal such as Al manufactured by an electroforming method. Flange members 211, 211' are attached to the substrate 21 and set to a shaft member 24 with fixtures 212, 212'. Since the surface roughness of the substrate 21 is about 0.3 S, an undercoat layer is made unnecessary. The substrate 21 is coated with a photosensitive material such as zinc oxide to form an image retaining layer 22.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in drum-shaped image carrier members used in electrostatic recording devices such as electrophotographic copying machines.

In an electrostatic recording device, a drum-shaped image carrier member (hereinafter simply referred to as a drum-shaped image carrier member) is used. An electrostatic latent image is formed on the image carrier] and developed.
A toner image is formed by developing the electrostatic WIfIl,
This toner image is transferred onto recording paper and fixed.

Conventionally, this image carrier has been used as a drum base by cutting an aluminum casting or an aluminum cylindrical tube, and depositing or coating a photoconductive substance or a dielectric substance on the circumferential surface of the drum base. In addition to aluminum, nickel, copper, brass, stainless steel, and other materials are used for the base material of the image carrier.The outer surface of the drum can be formed using a turning method using a diamond or other tool, a puff polishing method, or a super-finishing method. processing method,
Processed by liquid honing method etc. Even for drums made by precision casting, machining of the outer peripheral surface cannot be omitted due to the mating surfaces of the molds and the draft angle. Furthermore, when cutting a long cylindrical tube for use, the above-mentioned processing cannot be omitted.

For example, in order for an image carrier to be advantageously used in a photoconductive material layer provided on a drum substrate, either directly or through a suitable subbing layer, It is necessary that a specific drum surface condition be obtained. Surface roughness must be maintained within a certain range over the entire circumference. The magnitude of this surface roughness depends on the material of the drum base, the type of photoconductive material formed on the drum base,
Alternatively, when an undercoat layer is formed on the substrate and the photoconductive material, it is said that it is desirable that the undercoating layer is within the range of 0.3S to about 3.019, although it varies somewhat depending on the type etc. There is. - For example, when a selenium-based photosensitive material is formed on a drum base by vapor deposition, an electrophotographic photoreceptor (image bearing member) constructed of a drum base with a surface roughness of less than 0.1S may be used repeatedly. There is an extremely high risk that the photoconductive material layer will peel off.Also, an electrophotographic photoreceptor constructed of a substrate with a surface roughness greater than 3. The dark attenuation of the image becomes large, and the formed image becomes uneven due to the influence of the surface roughness.

For this reason, conventionally, various treatments have been carried out to obtain a surface roughness that corresponds to the original conductive layer and undercoat layer. Here, the undercoat layer acts as a barrier to the movement of carriers such as electrons or holes between the conductive substrate (drum substrate) of the photoreceptor and the photoconductive material, and also serves as a barrier to the movement of carriers such as electrons or holes between the drum substrate and the photoconductive material. It is set up to strengthen it.

Furthermore, in the past, the drum base of the image carrier had to be thick in order to maintain the roundness of the drum shape, that is, to prevent deformation, or to carry out the various surface treatments mentioned above. Because of their heavy weight and large inertia, large amounts of power are required to start and stop the rotation of the drum, which is inefficient and disadvantageous in transportation, attachment and detachment.

In addition to solving the requirements for an image carrier as described above, when an electrostatic latent image on an image carrier is developed by a magnetic brush developing device in a FLPL recording device (Fig. In an electrostatic copying machine that forms an electrostatic latent image using electrostatic charges, which is a type of recording device, an image carrier 10, which is a main part according to the present invention, and a rotatable magnet 132 provided in a toner developing device are used. With a developing roll 13 having
The developer is a one-component developer consisting of a magnetic toner that contains a magnetic substance in itself as described above, or a developer consisting of a carrier that is a needle-like magnetic substance or a spherical magnetic substance and a toner. Both two-component developers are used. ), and the distance between the image bearing member 10 and the developing roll 13 is a factor that greatly affects the developing performance. Since the developing seal 13 is placed extremely close to the developing seal 13, the movement (change) of the magnetic field affects the inside of the image carrier 10 near the wA developer. The image bearing layer 12 made of a photoconductive material or a dielectric material forming the cylindrical base 11 w/I, the cylindrical base 11 supporting the image bearing layer 1j!, and the arm 111 and the bearing are the parts 112, especially the cylindrical base 11. The material must be considered. Here, the developer support (
The sleeve) 131 may be rotated or may be fixed. If the cylindrical base 11 is made of a magnetic material, capri will occur in the image, resulting in a very poor seal image quality, so a non-magnetic material is used. For example, when aluminum is used as the non-magnetic material, the development of the image carrier! −
It is thought that induced eddy currents are generated in the area near the developing roller due to the movement of the developing roller and the magnetic field, which generates heat and increases the load on the drive device that rotates the image carrier.

At least the cylindrical base of the image carrier is made of a non-magnetic metal, and the thinner the thickness, the less likely the induced eddy current will occur. Therefore, by making the image carrier from a thin plate, the objects of the present invention can be achieved, which is lightweight and easy to transport. It has been achieved to obtain a good image carrier in which no tg-induced eddy currents occur. Of course, it is necessary that the cylindrical substrate has appropriate surface properties.

As an image bearing member that achieves this purpose, the present inventors used an endless belt made of non-magnetic metal with a thickness of 0.01 to 2 strips produced by electroforming as a drum base, and placed an endless belt on the drum base. A drum-shaped image carrier member on which an image carrier layer is formed is proposed.

Hereinafter, the present invention will be explained along with physical embodiments.

As is already well known, the electroforming method utilizes electrodeposition of a wire mesh in the same manner as plating, and is a method of manufacturing a product into a predetermined shape, and has the following advantages.

(1) The material can be selected from among many types. Among them are Ou, MulsW.

There are also non-magnetic materials such as Mo that can be used in the present invention.

(11) It is possible to easily make thin products that are difficult in the general metal industry. 0.01m required by the present invention
Seamless tubes and belts can be made with a thickness of Ng iai.

ODD: Can produce products with narrow tolerances and excellent surface quality.

Therefore, the present invention does not require surface treatment by mechanical processing, which was conventionally performed prior to attachment of an image bearing layer such as a photosensitive layer.

Now, the cylindrical surface is the electrode (cylindrical) that will be electrodeposited! Any desired level of smoothness can be achieved by controlling the surface properties and the amount of current used for electrodeposition. Although it depends on the material, it is effective for cyanide baths, and can produce surface roughness of about 0.1 seconds by controlling the current density, such as the Pi method, which changes the direction of direct current periodically, intermittent direct current, and superimposition of alternating current on direct current. Obtained through control. As mentioned earlier, the surface of the substrate for the photoreceptor is 0.3 to 3
It is desirable that it be within the range of B, and in this example, IS is used without machining the surface.

In this example, an image carrier layer was immediately formed on the circumferential surface of the thin cylindrical substrate to give it an appropriate level of smoothness without carrying out any processing such as surface polishing.

The image carrier layer provided on the cylindrical substrate 1 is, for example, selenium or an alloy vapor-deposited photosensitive material of selenium and tellurium, arsenic, etc., zinc oxide, zinc sulfide, cadmium selenide sulfide, cadmium sulfide, lead oxide, titanium oxide, etc. , a photosensitive layer in which an inorganic photoconductive substance such as mercury sulfide is dispersed in a resin, an organic photoconductive substance such as gelvinyllupasol, anthra7ine, polycyclic dyes, biryllium dyes, bisazo dyes, and 7-talocyanine pigments. The photosensitive layer used can be mentioned. These photoconductive layers can be formed by vapor deposition of selenium, etc., or by dissolving a photoconductive substance and a binder resin, etc. added if necessary, in these solvents and applying a composition to a cylindrical substrate. It is provided by applying a coating on the surface. As mentioned above, an undercoat layer may be formed on the cylindrical substrate for the purpose of improving the adhesion of the photoconductive material and as an electrical barrier, and the photoconductive material may be provided thereon. Further, as an image bearing layer that is not a photoconductive material, there is a dielectric layer.

f of the present invention by multi-stylus method, ion flow modulation, etc.
A schematic cross-sectional view of an embodiment of the IItfA carrier is shown in FIG.

In this example, a photoconductive material q122 was formed by coating zinc oxide dispersed in a resin to a thickness of 15 μm on the circumferential surface of an aluminum cylindrical substrate 21 produced by the above-mentioned electroforming method. The aluminum cylindrical base 21 of this embodiment has an outer diameter of 150 V.
Ans with a wall thickness of 250 μm and a length of 300 strips was prepared and used.

Incidentally, in order to provide the above-mentioned image bearing layer on the circumferential surface of the aluminum cylinder 21, it is necessary to prepare the image bearing layer on the steel shaft member 14 in advance as shown in FIG. 4F
In this example, an aluminum cylindrical base 81 has a disc-shaped end plate with m-number Φ rings at both ends (
7) A method of forming a 211° image bearing layer is also possible.

In addition to the image carrier thus produced, for comparison, an image carrier (comparison drum) similar to that of the previous example was produced except that a thin nickel plate was used as the cylindrical base. First, a commercial copying machine (Roku Konishi Photo Industry Co., Ltd.-IIU-sl) using the image carrier according to the present invention and a one-component magnetic toner as a developer
x T ), clear images were obtained on a large number of copies, and the following effects were particularly observed.

(1) No F-lux or Joule heat is generated on the drum base due to the alternating magnetic field, and it can withstand continuous copying for a long time.

(1) The inertia factor of the drum is small and the weight is reduced, the power required for driving and stopping the copying device is reduced, and the operation of attaching and detaching the drum is simplified.

- Preventing capri in component development and developing characteristics f
Stabilize.

Next, when I attached the above-mentioned comparison drum person to the above-mentioned commercially available copying machine and left it for a week, I made a copy and found that l1li11! A band-shaped capri was formed in a part of l. Of course, when the image bearing member of the present invention was attached, no capri was observed.

-Component Magnetic toner has a magnetic material as the main component as an F toner composition, and is mixed with a thermoplastic resin and additives (mold release agent, carbon black, charge control agent), etc. to form toner particles. The toner adheres to and develops the electrostatic latent image on the image carrier due to its own induced charge or triboelectric charge, but since the toner contains magnetic materials such as magnetite,
It is assumed that when the drum base is magnetized, it becomes a capri.

The photosensitive drum of the present invention is not magnetized, and therefore excellent effects can be obtained even in electrostatic recording devices using a one-component developer.

As described above, according to the present invention, an image carrier, more precisely, a drum-shaped image carrier, in which an endless belt made of a thin non-magnetic metal material is used as a cylindrical base to support an image carrier layer, is extremely lightweight and can be transported. This makes it easy to attach and detach from the electrostatic recording device. Since the cylindrical substrate is created by rough electroforming, the surface properties can be easily controlled, resulting in a highly accurate cylindrical substrate that does not require surface treatment.

Since this cylindrical base has flexibility, the more it is separated from the 7-rank member, the better it can be stored even if it remains deformed. In addition, as long as the image bearing layer is not destroyed or the performance deteriorates, even if the image bearing member (cylindrical base part) is deformed by a slight external force, the cylindrical base has a flexible structure, so it will function normally. This has resulted in a number of benefits, including the ability to return to its original shape and make it reusable.

[Brief explanation of the drawing]

FIG. 1 is a schematic view of the main parts of an electrostatic recording apparatus with an image bearing member and a developing roll taken out, and FIG. 2 is a schematic cross-sectional view of one embodiment of the present invention. 21... Aluminum thin cylindrical substrate U... Zinc sanide sensitive element layer (image bearing layer) Ell,
Ji! 11...7 rank member 84...Shaft member agent Yoshimi Kuwahara

Claims (1)

[Claims] A drum-shaped image carrier member in which an endless belt made of non-magnetic metal with a thickness of 0.01 to 2 m produced by electroforming is formed as a drum base layer, and an image carrier layer is formed on the drum base.