JPH0615699B2 - Photoconductive member for electrophotography - Google Patents

Description

The present invention relates to a photoconductive member for electrophotography.

[Conventional technology]

Aluminum alloys are widely used in various structures such as building materials and automobile parts. Especially, their use is increasing as a constituent member of electric or electronic devices that require precision processing such as a support for a photoconductive member. .

However, for example, general-purpose aluminum alloys such as wrought materials, castings, and Daigast standardized by the Japanese Industrial Standards (JIS) contain components such as Mg, Cu, Mn, Si, and Zn that are positively added. Various impurity components are contained in addition to various composition components such as the above, and these are precipitated as inclusions in the structure to cause a grain boundary step, or hydrogen gas exists in the structure as voids (Blister). As a result, the workability during precision processing is impaired, and the characteristics of electronic parts and the like having an aluminum alloy as a constituent member are deteriorated.

Such a situation will be described in more detail by taking a photoconductive member as an example. For example, an electrophotographic photosensitive member is usually formed by providing a photoconductive layer on the surface of a cylindrical support made of an aluminum alloy. It

Various organic or inorganic photoconductive substances are used as materials for the photoconductive layer. For example, amorphous silicon whose dangling bonds are modified with a monovalent element (hereinafter referred to as a-
Si) is expected to be applied as a material for the photoconductive layer because of its excellent optical conductivity, abrasion resistance and heat resistance. To provide the a-Si into practical use, in addition to the photoconductive layer of a-Si, a charge injection blocking layer for blocking the injection of charges from the support, SiN _X, a surface protective layer such as SiC _X It is necessary to use a multi-layer structure according to the purpose. At this time, the uniformity of the photoconductive member is extremely important, and if there are defects such as nonuniform photoconductive properties and pinholes, not only a beautiful image cannot be provided, but also it cannot be put to practical use.

In particular, it is known that the film shape of a-Si greatly affects the surface shape of the support. Especially, in the case of a large-area electrophotographic photosensitive drum, which requires almost uniform photoconductive properties in most parts, the surface condition of the support is extremely important. Deteriorates, and columnar structures and spherical projections are formed, which causes photoconductive nonuniformity.

However, when an aluminum alloy pipe material is used as a support, in the process of performing various precision cutting or polishing such as mirror finishing or embossing on the surface, a hard spot called a hard spot, for example, is caused by the above-mentioned various inclusions. Part is present, or there are holes (Bli
is present, it becomes a cutting resistance against a cutting tool in a mirror-finishing process by a cutting process, for example, causing a defective portion on the surface of the aluminum cylinder, cracks of 1 to 10 μm on the surface of the aluminum support, and an egre Is a factor that causes streaks such as scratches, fine fine irregularities, or voids (Blisters).

Therefore, the present inventors have found that the above-mentioned conventional problems can be solved by paying attention to the impurity component and the vacancy (Blister) in the aluminum alloy, and particularly by controlling the amount of hydrogen contained. The present invention has been completed.

[Object and Summary of Invention]

The electrophotographic photoconductive member of the present invention is an electrophotographic photoconductive member having a photoconductive layer on a support, wherein the support uses aluminum as a substrate, and the amount of hydrogen contained is 100 g of aluminum. It is characterized in that it is made of an aluminum alloy of 1.0 cc or less.

[Specific Description and Examples of Invention]

In general-purpose aluminum alloys, hydrogen that is produced, mixed and left in the process from electrolytic refining to plastic working such as rolling and extrusion generally exceeds 1 cc per 100 g of aluminum. There is. This causes a void-like structure abnormality in the structure of the alloy body, impairing workability during precision processing, and deteriorating the characteristics of electronic parts and the like obtained by precision processing. In the present invention, when the hydrogen content causing such inconvenience is about 1.0 cc with respect to 100 g of aluminum, the situation of the tissue abnormality greatly changes, and by suppressing the hydrogen content to 1.0 cc or less, the inconvenience due to the tissue abnormality is caused. It was found that If the hydrogen content exceeds 1.0 cc per 100 g of aluminum, defects are generated in the structure of the alloy body, as described above, and due to the bite during precision machining, for example, during the mirror finishing of the generated surface. The size and the existence density of the holes (Blister) that cause the defect are increased, and the holes (Blist) of 5 μm or more are formed.
er) is present, which is not preferable. The more preferable content of hydrogen is 0.
It is 7 cc or less. As a specific method for suppressing the hydrogen content in the aluminum alloy within the range specified in the present invention, for example, when the aluminum alloy is melted, chlorine gas is blown into the molten metal as a degassing step to exist in the alloy structure. A method of removing hydrogen gas as HCl or a method of holding the molten aluminum alloy in a vacuum furnace for a certain period of time and diffusing and removing the hydrogen gas existing in the alloy structure into a vacuum can be used.

As described above, in the present invention, the amount of hydrogen contained in the aluminum alloy is specified, but other alloy components such as the substrate aluminum are not particularly limited, and the kind of the component, the composition, etc. can be arbitrarily set. You can choose. Therefore, the aluminum alloy of the present invention is standardized or registered as a wrought material, casting, die casting, etc. in Japanese Industrial Standards (JIS), AA standard, BS standard, DIN standard, international alloy registration, etc. Aluminum type, Al
-Cu system, Al-Mn system, Al-Si system, Al-Mg
System, alloys of composition such as Al-Mg-Si system, Al-Zn-Mg system, Al-Cu-Mg system (duralumin, super-duralamine, etc.), Al-Cu-Si system (laural, etc.), Al
-Cu-Ni-Mg system (Y alloy, RR alloy, etc.), aluminum powder sintered body (SAP), etc. are included.

In the present invention, to select the composition of the aluminum alloy, as a characteristic according to the purpose of use, for example, mechanical strength,
It may be appropriately selected in consideration of the corrosion resistance, workability, heat resistance, dimensional accuracy, etc., but for example, in the case of precision machining, when accompanied by mirror cutting, coexist magnesium and copper in the aluminum alloy. This improves the free-cutting property of the aluminum alloy. The content of magnesium or copper is preferably in the range of 0.5 to 10% by weight,
Particularly, the range of 1 to 7% by weight is desirable. If the magnesium content is too high, intergranular corrosion is likely to occur in the crystal grain boundary portion, so it is not desirable to add more than 10% by weight.

Further, the iron contained in the aluminum alloy is such that the coexisting aluminum or silicon and the Fe-Al system or Fe-Al-S.
An i-based intermetallic compound is formed and appears as a hard spot in the aluminum matrix. In particular, this hard spot sharply increases as the iron content increases at an iron content of 2000 ppm, which adversely affects, for example, mirror cutting. Therefore, the preferable iron content in the aluminum alloy of the present invention is 2000 ppm or less, and further 1000
It is below ppm.

Incidentally, the concrete composition of the aluminum alloy of the present invention is illustrated below.

[Al-Mg system]

Mg 0.5-10 wt% Si 0.5 wt% or less Fe 0.25 wt% or less (preferably 2000 pp
m or less) Cu 0.04 to 0.2 wt% Mn 0.01 to 1.0 wt% Cr 0.05 to 0.5 wt% Zn 0.03 to 0.25 wt% Ti Tr or 0.05 to 0.20 wt % H ₂ Al 100 gram or less 1.0 cc Al substantially the balance [Al-Mn system] Mn 0.3 to 1.5 wt% Si 0.5 wt% or less Fe 0.25 wt% or less (preferably Is 2000pp
m or less) Cu 0.05 to 0.3 wt% Mg 0.2 to 1.3 wt% Cr 0 or 0.1 to 0.2 wt% Zn 0.1 to 0.4 wt% Ti Tr or 0. About 1% by weight H ₂ Al 100 gram or less 1.0 cc Al substantially the balance [Al-Cu system] Cu 1.5 to 6.0% by weight Si 0.5% by weight or less Fe 0.25% by weight Below (preferably 2000pp
m or less) Mn 0 or 0.2 to 1.2 wt% Mg 0.2 to 1.8 wt% Cr about 0.1 wt% Zn 0.2 to 0.3 wt% Ti Tr or 0.15 to 0.2 wt% H ₂ Al 100 grams 1.0cc or less Al substantially balance [Al-Mg-Si-based] Mg 0.35 to 1.5 wt% Si 0.5 to 10 wt% Fe 0.25% by weight or less based on (Preferably 2000 pp
m or less) Cu 0.1 to 0.4 wt% Mn 0.03 to 0.8 wt% Cr 0.03 to 0.35 wt% Zn 0.1 to 0.25 wt% Ti Tr or 0.1 to 0.15 wt % H ₂ Al 100 gram or less 1.0 cc Al substantially the balance [pure aluminum-based] Mg 0.05 to 0.5 wt% Si 0.3 wt% or less Fe 0.25 wt% or less (preferably 2000pp
m or less) Cu 0.03 to 0.1 wt% Mn 0.02 to 0.05 wt% Cr Tr Zn 0.03 to 0.1 wt% Ti Tr or 0.03 to 0.1 wt% H ₂ Al 100 g 1.0 cc or less Al Substantially the rest (however, Tr means the amount of traces when not positively added.) The aluminum alloy of the present invention is subjected to plastic working such as rolling and extrusion, and then cutting. Or mechanical treatment such as polishing, or precision processing accompanied by chemical or physical method such as chemical etching, and optionally heat treatment, tempering, etc. are optionally combined, and an appropriate treatment according to the purpose of use is performed. Shaped into shape. For example, when shaping into a tubular component member that requires strict dimensional accuracy such as an electrophotographic photosensitive drum, a porthole extruded tube or a mandrel extruded tube obtained by ordinary extrusion processing is used.
Further, it is preferable to use a drawn tube obtained by cold drawing, and using such a tube, for example, a mirror surface finish of the tube surface, a mechanical method such as cutting or polishing for embossing, or a chemical method. The characteristics of the aluminum alloy of the present invention are particularly remarkable when subjected to precision processing involving chemical or physical methods such as etching.

The aluminum alloy of the present invention is most suitable for a support for a photoconductive member such as an electrophotographic photoreceptor, a magnetic disk substrate for a computer memory, a polygon mirror substrate for a laser scan, a mirror surface finish by a diamond tool, a cylindrical grinding finish, lapping. R _max = 1 using means such as finishing
Surface roughness of less than or equal to μm, preferably R _max = 0.05
It is useful as a constituent member of various electric or electronic devices that are finished to a flatness of μm or less.

Hereinafter, using the aluminum alloy of the present invention as a support,
Regarding the photoconductive member for electrophotography using a-Si as the photoconductive substance, a configuration example of the photoconductive member of the present invention will be described.

Such a photoconductive member has, for example, a structure in which a charge injection blocking layer, a photoconductive layer (photosensitive layer) and a surface protective layer are sequentially laminated on a support.

The shape of the support may be verified as desired, but in the case of use for electrophotography, for example, in the case of continuous high speed copying, it is desirable to have an endless belt shape or a cylindrical shape.
The thickness of the support is appropriately determined so that a desired photoconductive member is formed, but when flexibility is required as the photoconductive member, a range in which the function as a support is sufficiently exhibited If it is inside, it will be made as thin as possible. However, even in such a case, it is usually 10 μm or more from the viewpoints of production and handling of the support, and mechanical strength and the like.

In order to maintain the uniformity of the photoconductive member, the surface of the support is mirror-finished by, for example, mirror-cutting processing, and digital image information using coherent monochromatic light such as laser light with the photoconductor as the light source. When used for recording, in order to prevent interference fringe patterns, for example, by means of mechanical precision machining such as diamond cutting using a lathe, milling machine, etc. or other precision machining such as chemical etching Fine irregularities are attached.

The charge injection blocking layer is composed of, for example, a-Si containing a hydrogen atom and / or a halogen atom, and is a substance that controls conductivity, and is usually used as an impurity of a semiconductor. It contains atoms of elements belonging to Group V. The layer thickness of the charge injection blocking layer is preferably 0.01 to 10 μm, more preferably 0.05 to 8 μm,
Optimally, it is desirable that the thickness is 0.07 to 5 μm.

Instead of the charge injection blocking layer, for example, Al ₂ O ₃ , Si
A barrier layer made of an electrically insulating material such as O ₂ , Si ₃ N ₄ or polycarbonate may be provided, or the charge injection blocking layer and the barrier layer may be used in combination.

The photoconductive layer is made of, for example, a-Si containing hydrogen atoms and halogen atoms, and if desired, contains a quality of conductivity different from that used for the charge injection blocking layer. The layer thickness of the photoconductive layer is preferably 1 to 100 μm, more preferably 1 to 80 μm, and most preferably 2 to 50 μm.

The surface protective layer is composed of, for example, SiC _X , SiN _X, or the like, and the layer thickness is preferably 0.01 to 10 μm, more preferably 0.02 to 5 μm, and most preferably 0.04 to 5 μm. Is desirable.

In the present invention, to form a photoconductive layer composed of a-Si, for example, a glow discharge method, a sputtering method,
Alternatively, a vacuum deposition method utilizing various known discharge phenomena such as an ion plating method, which utilizes the discharge phenomenon, is applied.

Next, an example of a method for manufacturing a photoconductive member by the glow discharge decomposition method will be described.

FIG. 1 shows an apparatus for producing a photoconductive member by the glow discharge decomposition method. The deposition tank 1 is composed of a base plate 2, a tank wall 3 and a top plate 4. Inside the deposition tank 1, a cathode electrode 5 is provided, and a specific composition for forming an a-Si deposition film is formed. The aluminum alloy drum-shaped support body 6 is installed in the central portion of the cathode electrode 5 and also serves as an anode electrode.

In order to form an a-Si deposited film on the drum-shaped support using this manufacturing apparatus, first, the source gas inflow valve 7 and the leak valve 8 are closed, the exhaust valve 9 is opened, and the deposition tank 1
Exhaust the inside. The reading of the vacuum gauge 10 is about 5 × 10 ^-6 torr
When the temperature reaches r, the raw material gas inflow valve 7 is opened to deposit a raw material mixed gas, such as SiH ₄ gas, Si ₂ H ₆ gas, or SiF ₄ gas, which is adjusted to a predetermined mixing ratio in the mass flow controller 11. It is made to flow into the tank 1. At this time, the vacuum gauge 10 is adjusted so that the pressure in the deposition tank 1 reaches a desired value.
The opening degree of the exhaust valve 9 is adjusted while watching the reading.
The surface temperature of the drum-shaped support 6 is the heater 1
After confirming that the temperature is set to a predetermined temperature by 2, the high frequency power supply 13 is set to a desired power to cause glow discharge in the deposition tank 1.

During the layer formation, the drum-shaped support 6 is rotated at a constant speed by the motor 14 in order to make the layer formation uniform. In this way, on the drum-shaped support 6,
An a-Si deposited film can be formed.

Hereinafter, the present invention will be described in more detail based on examples.

Examples 1 to 3 and Comparative Examples 1 and 2 Lathe with air damper for precision cutting (manufactured by PNEUMO PRECISION INC.)
Then, a diamond bite having a tip curvature of 0.01 (mm ^-1 ) was set so as to obtain a negative rake angle of 5 ° with respect to the cylinder center angle. Next, on the rotary shaft flange of this lathe,
5 types of Al-Mg-based aluminum alloy cylinders with different hydrogen contents shown in Table 1 (Mg contents are all 4% by weight, Fe contents are 2000 ppm or less) are vacuum-checked, and white kerosene is sprayed from the attached nozzles. , A peripheral speed of 10 while using suction of cutting chips from a vacuum nozzle also attached.
Mirror cutting was performed under the conditions of 00 (m / min) and a feed rate of 0.01 (mm / R) so that the outer diameter was 80 mmΦ.
With respect to a cylinder that has been mirror-finished in this way, surface defects (egre-like scratches, cracks,
The number of streaky scratches caused by the holes was examined visually and by a metallurgical microscope. The amount of hydrogen contained in Cylinder E was cut out from a part of the prepared cylinder, and this sample was used as a sample and measured according to the specifications using a model RH-1E manufactured by Laboratory Equipments Corporation.

Next, on each of these mirror-finished aluminum alloy cylinders, using the photoconductive member manufacturing apparatus shown in FIG. 1, according to the glow discharge decomposition method detailed above,
A photoconductive member was produced under the following conditions.

Aluminum cylinder temperature: 250 ° C. Internal pressure of deposition chamber during deposition film formation: 0.3 Torr Discharge frequency: 13.56 MHz Deposition film formation rate: 20 Å / sec Discharge power: 0.18 W / cm ² Electrophotographic photoreceptors thus obtained The drum was installed in a 400RE copying machine manufactured by Canon Inc. to perform image formation, and white dot image defects (0.3 mmΦ or more) were evaluated. The results of these evaluations are shown in Table 1.

For each of the electrophotographic photosensitive drums of Examples 1 to 3, a durability test of 1 million sheets was performed at 23 ° C./relative humidity of 5
0%, 30 ° C / 90% relative humidity, 5 ° C / 20% relative humidity
It was confirmed that it has good durability without any increase in image defects, especially defects such as white spots.

Examples 4 to 6 and Comparative Examples 3 to 5 Instead of Al-Mg based aluminum alloy, Al-Mn
The same aluminum alloy cylinder and photoconductive member as in Example 1 were prepared, except that the Al, Mg, Si, and pure aluminum aluminum alloys (each Fe content was 1000 ppm or less) were used.

The number of defects generated in the mirror-finishing process of the cylinder thus obtained and the image defects at the time of image formation were evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[Advantages of the Invention] According to the aluminum alloy of the present invention, structural abnormalities such as voids (Blister) due to contained hydrogen are suppressed or completely eliminated, resulting in deterioration of workability due to precision processing and desired processed products. Since deterioration of characteristics is suppressed, components of electric or electronic devices that require precision processing,
Particularly, it is suitable as an electric or electronic device constituent member such as a photoconductive member for which an accurate surface shape is desired by precision processing, a magnetic disk substrate for a computer memory, a polygon mirror substrate for a laser scan, and the like.

Further, since the pipe material obtained by drawing this aluminum alloy can obtain an accurate surface shape and high dimensional accuracy, it is particularly suitable for forming a precise tubular component member such as a support for an electrophotographic photosensitive drum. Is.

Furthermore, the photoconductive member using the aluminum alloy of the present invention as a support is excellent in the uniformity of electrical, optical or photoconductive properties, and when used for electrophotography, there are few image defects. , You can get high quality images.

[Brief description of drawings]

FIG. 1 is a view showing an apparatus for manufacturing a photoconductive member by the glow discharge solution method. 1 ... Deposition tank, 2 ... Base plate, 3 ... Tank wall, 4 ... Top plate, 5 ... Cathode electrode, 6 ... Drum-like support, 7 ... Raw material gas inflow valve, 8 ... Leak valve . 9 ... Exhaust valve, 10 ... Vacuum gauge, 11 ... Mass flow controller, 12 ... Heating heater, 13 ... High frequency power supply, 14 ... Motor.

Claims (4)

[Claims] 1. A photoconductive member for electrophotography having a photoconductive layer on a support, wherein the support uses aluminum as a substrate and the amount of hydrogen contained is 1.0 cc or less per 100 g of aluminum. A photoconductive member for electrophotography, which is made of an aluminum alloy. 2. The photoconductive member for electrophotography according to claim 1, wherein the photoconductive layer includes a layer made of an amorphous material containing silicon atoms. 3. The photoconductive member for electrophotography according to claim 1, wherein the aluminum alloy contains magnesium in an amount of 0.5 to 10% by weight. 4. The aluminum alloy contains 2000 ppm of iron.
The photoconductive member for electrophotography according to claim (1), which further comprises: