JPS5849623A - Preparation of photoconductive material - Google Patents

Abstract

PURPOSE:To obtain gamma-crystal photoconductive material from molten bismuth- based compound oxide, easily, by cooling and solidifying the molten bismuth- based compound oxide under contact with nickel. CONSTITUTION:Molten bismuth-based compound oxide of formula (M is Ge, Si, Ti, Ga or Al; 10<=X<=14; n is number of oxygen atoms) is made to contact with nickel, and cooled and solidifed at a cooling rate of preferably <=20 deg.C/min to obtain gamma-crystal of the compound oxide. A large amount of gamma-crystal can be obtained easily from a large amount of molten compound oxide by using a large- volume heat-resistant vessel having nickel inner wall, e.g. a vessel made of nickel. In this case, a thin gamma-crystal plate can be obtained by using a very shallow heat-resistant vessel.

Description

DETAILED DESCRIPTION OF THE INVENTION In more detail fd The present invention relates to a method for producing a hismuth oxide-based composite oxide photoconductive material.

JP-A-53-4.3531 has a compositional formula of Bi) (He40,1 (where LM is at least one of kermanium, silicon, titanium, gallium, and aluminum, and
is a number that satisfies the condition 10≦X≦14, and n indicates the number of oxygen atoms determined stoichiometrically depending on M and X above. Oxides are not conductive when exposed to X-rays or γ-rays, so
It is disclosed that the material can be used as a photoconductive material for a photoreceptor used in electrophotography VC, in which an electrostatic latent image is formed by irradiation with radiation or gamma rays. Also, for example, [Journal of Applied Phys.
Bit2C3eO! in icsJ Vol. 42, pp. 493-494 (1971). O and l-3 i +2 8
The crystalline composite oxide described above becomes conductive even when exposed to pure visible light irradiation, and therefore is suitable for electrophotography in which an electrostatic latent image is formed by irradiation with visible light. It is also useful as a photoconductive material for photoreceptors used. There are two crystal systems in the above-mentioned gold dust oxide: a body-centered cubic system (γ type) and a face-centered cubic system (δ type), but it is the former that exhibits the above-mentioned photoconductivity. It is.

It is known that the γ-type crystal of the above-mentioned complex oxide can be produced by the Czochralski method, which is a general sheep crystal production method, that is, the pulling method using all the seed crystals [for example, Vr. 'Journal of Cry
stal QrowLh, J Vol. 1, pp. 37-40 (
(1967)]. In addition, as another method for producing the γ-type crystal from the melt of the above-mentioned complex oxide, especially Ll
．． i +28 i02.

About double crucible? The temperature gradient slow cooling method used is known (preliminary of the 41st Spring Annual Meeting of the Chemical Society of Japan [γ-68+203・Si02 by temperature gradient slow cooling method using a double crucible].
(See Production of Crystal Plates I).

According to these methods, the γ-type crystal of the above composite oxide can be obtained as a single crystal or a polycrystal close to a single crystal. However, these methods are not suitable for producing all the γ-type crystals of the above-mentioned complex oxide easily and in large quantities.

It is known that when the melt of the above composite oxide is completely cooled and assimilated, a δ-type crystal is generally formed.
But Ietin of the Institute
e for Chemical R, search
J Vol. 55, No. 5, pp. 447-456 (1977)
As described in , when the melt of the above composite oxide is subjected to mechanical shock such as vibration when cooling and solidifying, a γ-type crystal (generally polycrystal) is generated. . Therefore, by applying a mechanical shock such as vibration to the melt of the composite oxide placed in a heat-resistant container such as a platinum crucible, and cooling and solidifying the melt from the surface, the γ-type crystal of the composite oxide can be obtained. can be easily produced in large quantities.

In this way, the method described above is currently most suitable for producing γ-type crystals easily and in large quantities from a bath melt of the above complex oxide, which involves applying a mechanical shock to the melt when it is cooled. It is. However, if it is possible to generate γ-type crystals by simply cooling and solidifying the composite oxide melt without applying mechanical shock to the complex oxide melt, then the method would be to It is clear that this method is simpler than the method of applying mechanical shock to the γ-type crystals, and is therefore more attractive as a commercial method for producing γ-type crystals.

Further, the above-mentioned Japanese Patent Application Laid-Open No. 53-43531 describes an electrophotographic photoreceptor using the above-mentioned crystalline bismuth oxide-based composite oxide as a photoconductive material (the crystal system of the composite and oxide used is (There is no mention of whether it is a γ type or a δ type), and this electrophotographic photoreceptor is manufactured by the following two methods.

In the first method, first, a coating of crystal particles of the composite oxide is formed on a conductive substrate. It is stated that this crystal particle coating is formed by a vapor deposition method, a spray method, or the like.

The crystal grain coating is then sintered into a thin plate-like crystal body. In this sintering process, the crystal particles are mechanically bonded to each other to form a thin plate-like crystal body, and at the same time, a portion of the crystal particles is also mechanically bonded to the conductive substrate. That is, what is manufactured by the first method comprises a conductive substrate and a thin plate-like crystal of the composite oxide mechanically bonded to one surface of the conductive substrate, and the thin plate-like crystal is an electrophotographic photoreceptor which is a sintered body of crystal particles of the above composite oxide. Also, as an alternative to the first method above,
A method is described in which crystal particles of a composite oxide are first sintered to form a thin plate-like crystal, and then one surface of a conductive substrate is coated with the thin plate-like crystal.

In the second method, a thin plate-like crystal of the composite oxide is brought into contact with one surface of a conductive substrate using a conductive binder. That is, the electrophotographic photoreceptor manufactured by this second method has a structure in which a conductive substrate, a conductive binder layer, and a thin plate-like crystal of the composite oxide are laminated in this order. Although it is believed that the lamellar crystalline body adhered to the conductive substrate by the conductive binder is generally cut from a large crystal block, the lamellar crystalline body may be a single crystal thin plate cut from a single crystal 4. Alternatively, it may be a polycrystalline thin plate cut from polycrystalline material.

However, the first method (sintering method) and the second method (bonding method) have the following drawbacks.

1. Neither the sintering method nor the adhesion method can be called a simple method for producing electrophotographic photoreceptors. The sintering method mainly consists of two steps: formation of a crystal particle coating on a conductive substrate and sintering of the crystal particle coating. For example, in the former process, in order to obtain a coating of uniform thickness, (ie, to obtain a sintered crystal of uniform thickness) requires careful control of the conditions for film formation. In addition, the adhesion method consists of two steps: cutting out a thin plate-like crystal from the crystal 4 and bonding the thin plate-like crystal to a conductive substrate using a conductive binder. It is very difficult to cut out a thin plate-like crystal with a certain thickness, and additional operations such as grinding and polishing are required.

2. Electrophotographic photoreceptors need to have a relatively large area, but both sintering and bonding methods are unsuitable for manufacturing large-area electrophotographic photoreceptors; It is almost impossible to manufacture a large-area electrophotographic photoreceptor using an adhesive method.

3 In the sintering method, as mentioned above, some of the crystal particles (crystal particles in contact with the conductive substrate) are removed during the sintering process.
is mechanically bonded to the conductive substrate, thereby bonding the thin plate crystal to the 2s conductive substrate, but the bonding force cannot be said to be that of light.

4. The thin plate-like crystalline material of the electrophotographic photoreceptor obtained by the sintering method is a sintered body of crystal grains, so to speak, it is an aggregate of crystal grains in which the crystal grains are mechanically bonded to each other, so it is not very dense. It also has low mechanical strength.

5. In electrophotographic photoreceptors obtained by adhesion methods, the performance of the thin plate-like crystalline material as a photoconductive material is easily affected by the conductive binder ().

Neither the sintering method nor the adhesion method directly forms a thin plate-like crystal from the amorphous composite oxide on a conductive substrate, and this is the fundamental cause of the drawbacks of these methods. It is thought that this is the case. Therefore, a thin plate-like crystal is deposited on a conductive substrate from a molten liquid of a composite oxide.
By F-contact formation, in other words, the production of a photoconductive material in which a composite oxide melt is made into a crystal is carried out on a conductive substrate. It is believed that the above-mentioned drawbacks of the conventional method can be improved by manufacturing the material in the form of a thin plate.

The present invention was carried out under the circumstances described above, and broadly aims to provide a new method for producing a γ-type crystalline photoconductive material from a bath melt of the above-mentioned composite oxide. That is.

More specifically, the present invention provides a method for easily producing a γ-type crystalline photoconductive material from the above-mentioned composite oxide melt by simply cooling and solidifying the melt without applying mechanical shock to the melt. The purpose is to provide a method to do so.

Another object of the present invention is to provide a method for producing a large amount of γ-type crystalline photoconductive material from a melt of the above-mentioned composite oxide.

A further object of the present invention is to provide a method for producing a γ-type crystalline photoconductive material in the form of a thin plate from a melt of the composite oxide on a conductive substrate.

The present inventors have so far conducted various studies on methods for producing γ quasicrystals from the composite oxide melt. As a result, it was discovered that when the melt of the above composite oxide is cooled and solidified in contact with nickel, a γ quasicrystal is formed without applying mechanical shock to the bath melt during cooling, and the present invention is based on the present invention. was completed.

The method for producing a photoconductive material of the present invention has a compositional formula of 13 i x MOn (where M is at least one of germanium, silicon, titanium, gallium, and aluminum, and X satisfies the condition 10≦X≦14). and n indicates the number of oxygen atoms determined stoichiometrically depending on the above M and The composite oxide is characterized by being made into a γ quasicrystal.

As a first specific example of the production method of the present invention, a molten liquid of the above composite oxide placed in a heat-resistant container such as a nickel container whose at least the inner surface is made of nickel is cooled and solidified to obtain the γ level. Examples include methods for producing crystals. According to this first specific example, by using the heat-resistant container with a large capacity, a large amount of γ quasicrystals can be produced very easily from a large amount of composite oxide melt contained in the container. Can be done. According to the first specific example, by using the heat-resistant container with a very shallow bottom, a thin plate-like γ quasicrystal can be produced from the composite oxide melt contained in the container. Obtained thin plate-like γ
The type crystal can be used as an electrophotographic photoreceptor by adhering it to one surface of a conductive substrate using a conductive binder, for example, as in the above-mentioned adhesive method.

Further, as a second specific example of the manufacturing method of the present invention, the molten liquid of the composite oxide is cooled and assimilated on the nickel surface of a conductive substrate such as a nickel plate (one surface of which is made of nickel). The thin plate-like γ is formed on the nickel surface by
Examples include a method of forming a type crystal. According to this second specific example, it is possible to obtain an electrophotographic photoreceptor comprising the above-mentioned conductive substrate and the thin plate-like γ-type crystal of the above-mentioned d oxide, which is mechanically bonded to the nickel surface of the conductive substrate. I can do it. That is, this second specific example is a method for manufacturing an electrophotographic photoreceptor, and in this method for manufacturing an electrophotographic photoreceptor, the drawbacks of the conventional sintering method or adhesion method described above are improved.

The present invention will be explained in detail below.

In the manufacturing method of the present invention, the melt of the bismuth oxide-based composite oxide is cooled and solidified into a γ-type crystal while being brought into contact with nickel. It may be prepared by heating and melting the oxide, or it may be prepared simultaneously with the production of the composite oxide by heating and melting the raw material mixture of the composite oxide. In the former case, the amorphous composite oxide may be heated and melted to form a molten liquid, or the δ-type crystal of the composite oxide or the crystal particles obtained by crushing the crystal may be heated and melted. It may also be made into a melt. Of course, a γ-type crystal of a composite oxide produced by another method or crystal particles obtained by crushing the crystal may be heated and melted to form a melt. On the other hand, in the latter case, the raw materials for the composite oxide include 1) bismuth oxide (Biz(h)) and hydroxides, carbonates, nitrates, etc. that can be easily converted into Biz at high temperatures;
11) germanium oxide (Ge0z), silicon dioxide (
Si02), titanium dioxide (TiOz), gallium oxide (Ga203) and aluminum oxide (A720
The first compound group consisting of
At least one compound selected from the second compound group consisting of a germani-lam compound, a silicon compound, a titanium compound, a gallium compound and an aluminum compound that can be converted into A4!02, Ti0z, GazO3 and A4!03 is used. It will be done. The above two raw materials have a stoichiometric compositional formula (%) (where M is at least one of germanium, silicon, titanium, gallium, and aluminum, and X is a number that satisfies the condition 10≦X≦14). and n represents the number of oxygen atoms determined chemically depending on M and X above) and are sufficiently mixed to obtain a mixture. Thereafter, the obtained raw material mixture is heated and melted, whereby a composite oxide represented by the above compositional formula is produced, and at the same time, a molten liquid thereof is prepared.

The above melt may be prepared in direct contact with nickel by bringing the composite oxide or its raw material mixture into contact with nickel and heating and melting it, or alternatively, it may be prepared separately and then placed in contact with nickel. It's okay if it gets lost. That is, in the first specific example of the manufacturing method of the present invention, the molten liquid is a composite oxide or a raw material mixture thereof placed in a heat-resistant container such as a nickel container whose at least the inner surface is made of nickel, and the container is heated. It may be prepared directly in the container, or it may be prepared elsewhere and then placed in the container. Further, in the second specific example of the manufacturing method of the present invention, the molten liquid is prepared by placing the composite oxide or its raw material mixture on the nickel surface of a conductive substrate such as a nickel plate, at least one surface of which is made of nickel. may be prepared directly on the nickel side of the substrate by heating with the substrate, or may be prepared elsewhere and then placed on the nickel side of the substrate. In general, it is preferable to prepare the melt in a state in which it is in direct contact with nickel, for reasons such as easier operation. The bath melt is generally prepared in an oxidizing atmosphere such as air (ambient atmosphere) or an inert atmosphere such as a nitrogen atmosphere or argon atmosphere in order to prevent the composite oxide from being reduced during the melting process. It will be done.

complex oxide melt in contact with nickel;
That is, the composite oxide melt in the heat-resistant container or on the nickel surface of the conductive substrate is cooled and solidified.

This cooling is performed by a cooling method generally employed in the field of crystal manufacturing technology, such as slow cooling of the molten liquid in contact with nickel in an electric furnace. Generally, it is preferred that the melt be cooled at a rate of 20°C/min or less. This cooling solidifies and crystallizes the composite oxide melt into its γ quasicrystal. The γ quasicrystal that is generally produced is a polycrystalline body made up of aggregation of fine crystals, although it varies depending on cooling conditions and the like.

In addition, regardless of the method used to cool the above-mentioned composite oxide melt, in order to prevent the composite oxide from being reduced during cooling, it is generally cooled in an oxidizing atmosphere such as air, nitrogen atmosphere, argon atmosphere, etc. carried out in an inert atmosphere.

From the viewpoint of photoconductivity of the obtained γ quasicrystal, it is preferable that M in the above compositional formula is germanium and/or silicon in the bismuth oxide-based composite oxide used in the production method of the present invention. A certain composite oxide, that is, its compositional formula is represented by Bix(Ge1-y, 5iy)On (where X and n have the same definitions as above, and y is a number that satisfies the condition 0≦y≦1). Particularly preferred are the oxides to be combined. Among these specific composite oxides, a composite oxide having the above compositional formula 0 (i.e., I3i 12GeOzo
) and a composite oxide in which X is 12, y is 1, and n is 20° (ie, B11z5iO2o) is particularly preferred.

According to the method of the present invention, a γ quasicrystal can be produced by simply cooling and solidifying the composite oxide melt without applying a mechanical shock to the complex oxide melt. Therefore, in the method of the present invention, mechanical shock is applied to the melt during cooling, and γ
This method is simpler than conventional methods for producing quasicrystals, and in this respect is superior as a method for producing γ quasicrystals. As explained above, when a complex oxide melt is assimilated by simply cooling it without applying mechanical shock to it, a δ-type crystal is produced. In the method of the present invention,
The reason why γ-type crystals are produced by cooling and solidifying a composite oxide melt while in contact with nickel is not clear at present.

As mentioned above, in the first specific example of the manufacturing method of the present invention,
In this case, the molten liquid of the oxides to be combined is cooled and solidified into a γ quasicrystal in a heat-resistant container such as a nickel container, at least the inner surface of which is made of nickel. This first concrete example is γ
Suitable for producing large quantities of quasicrystals.

That is, by using the heat-resistant container with a large capacity, a large amount of γ quasicrystal can be produced very easily from a large amount of melt contained in the container. In this case, generally a cup-shaped or box-shaped heat-resistant container with a relatively deep bottom (for example, a nickel crucible) is used, and therefore the γ quasicrystal is obtained as a crystal observation, but this cohesive mass is placed in a heat-resistant container. After being taken out, it is cut into small pieces or crushed into powder and used as a photoconductive material.

According to the first specific example, by using the heat-resistant container with a very shallow bottom, it is possible to produce a thin plate-like γ quasicrystal from the composite oxide bath melt placed in the container. can.

In this case, in order to obtain a lamellar gamma quasicrystal with a uniform thickness, the heat-resistant trough is held horizontally during cooling of the melt, thereby keeping the melt horizontal. Obtained thin plate-like γ
The quasicrystal can be used as an electrophotographic photoreceptor by being taken out of the heat-resistant container and bonded to one surface of a conductive substrate using an isoelectric binder, for example, as in the above-mentioned bonding method. As explained earlier, thin plate-like γ-type crystals were generally obtained by cutting out a large crystal body, but it was extremely difficult to cut out thin-plate-like γ quasicrystals with uniform thickness. . According to the first embodiment of the production method of the present invention, a thin plate-like γ quasicrystal of uniform thickness can be easily produced by using the heat-resistant container with a very shallow bottom as described above. can. Also, the emergency at the bottom = 23
- By using the above-mentioned heat-resistant container that is shallow and large in area, a thin plate-like γ quasicrystal with a large area can be easily produced.

Further, in the second specific example of the manufacturing method of the present invention, the composite oxide melt is cooled and solidified on the nickel surface of a conductive substrate such as a nickel plate, at least one of which is made of nickel. A thin plate-like γ quasicrystal is formed on the nickel surface of the conductive substrate. According to this second specific example, a composite consisting of the conductive substrate and a thin plate-like γ quasicrystal of a composite oxide mechanically crystallized on the nickel surface of the conductive substrate is obtained. The body can be used as an electrophotographic photoreceptor. That is, this second
A specific example is a method for manufacturing an electrophotographic photoreceptor.

Composite obtained by the above-mentioned second specific example (hereinafter, the specific example of tube 2 will be referred to as "the electrophotographic photoreceptor manufacturing method of the present invention"), that is, a thin plate-like γ quasicrystal conductive substrate of an electrophotographic photoreceptor. 24- The mechanical bonding force against the conductive substrate of the electrophotographic photoreceptor produced by the conventional sintering method is significantly greater than the mechanical bonding force with respect to the conductive substrate, and is sufficient for practical use. It is.

This is because in the sintering method, the crystal particles of the composite oxide are brought into contact with the conductive substrate, whereas in the electrophotographic photoreceptor manufacturing method of the present invention, the bath melt of the composite oxide is brought into contact with the conductive substrate. This is because it will be done. In addition, the thin plate-like γ quasicrystal of the electrophotographic photoreceptor obtained by the electrophotographic photoreceptor manufacturing method of the present invention has a strong cohesive force because it is obtained by cooling and solidifying the melt of the composite oxide. Therefore, it is denser than the thin plate-like crystal body of an electrophotographic photoreceptor manufactured by the sintering method, which is an aggregate of crystal grains in which crystal grains are mechanically bonded to each other by sintering, and also has higher mechanical strength. . The thickness of this thin plate-like γ quasicrystal is basically determined by the thickness of the composite oxide melt placed on the conductive substrate during production. Therefore, specifically, by appropriately selecting the weight per unit area of the composite oxide melt placed on the conductive substrate, a thin plate-like γ quasicrystal of desired thickness can be formed. Generally, the thickness of the thin plate-like γ quasicrystal is preferably 0.01 to 5 mm, more preferably 0.1 to 3 TAN. In the method for manufacturing an electrophotographic photoreceptor of the present invention, in order to form a thin plate-like γ quasicrystal having a uniform thickness, the conductive substrate is held horizontally during cooling, so that the molten liquid is held horizontally. It is maintained. As mentioned above, the thin plate-like γ quasicrystals produced by cooling are generally polycrystals made up of fine crystals, and therefore generally have relatively good surface flatness. However, after cooling, the surface of the thin plate-shaped γ-type crystal may be ground or polished to improve its flatness, if necessary.

Unlike the conventional sintering method and adhesion method described above, the electrophotographic photoreceptor manufacturing method of the present invention cools and solidifies a molten liquid of a composite oxide placed on a conductive substrate, and then deposits it on the substrate. This forms a thin plate-like γ quasicrystal. Therefore, as described below, in the method of manufacturing an electrophotographic photoreceptor of the present invention, the drawbacks of the conventional sintering method and adhesion method are improved.

1. Although there is a restriction that a conductive substrate, such as a nickel plate, at least one side of which is made of nickel must be used, the method of the present invention can be applied to composites placed on such a conductive substrate. The method of the present invention simply cools and solidifies the molten oxide to form a thin plate-like γ quasicrystal. Therefore, the method of the present invention allows electrophotographic exposure to be performed more easily than conventional sintering or bonding methods. body can be manufactured. Furthermore, in the method of the present invention, a thin plate-like r-type crystal with a uniform thickness can be formed simply by holding the conductive substrate horizontally during bath melt aging.

2. The method of the present invention is suitable for manufacturing large-area electrophotographic photoreceptors. That is, a large-area electrophotographic photoreceptor can be easily manufactured simply by using the above-described large-sized conductive substrate.

3. As explained above, the bonding force of the thin plate-like γ quasicrystal of the electrophotographic photoreceptor manufactured by the method of the present invention to the conductive substrate is greater than that of the thin plate-like electrophotographic photoreceptor manufactured by the sintering method. This is significantly greater than the bonding force of the crystal to the conductive substrate, and is sufficient for practical use.

4. As also explained earlier, the thin plate-like γ quasicrystal of the electrophotographic photoreceptor produced by the method of the present invention is denser than the thin plate-like crystal of the electrophotographic photoreceptor produced by the sintering method. It also has high mechanical strength.

5. In the electrophotographic photoreceptor manufactured by the method of the present invention, the thin plate-like γ quasicrystal is not adhered to the conductive substrate with a binder, but is directly mechanically bonded to the conductive substrate. Therefore, unlike an electrophotographic photoreceptor manufactured by an adhesive method, the performance of the thin plate-like γ quasicrystal as a photoconductive material is not affected by the binder.

Next, the present invention will be explained by examples.

Example 1 Diameter: 50 mm, height: 40 mm, thickness: 0.5 myn
BizOa of 578.4.9 and 21 in a nickel crucible of
．． The crucible was charged with 6 g (3eO2) of the mixture. The crucible was placed in an electric furnace and heated in air to 950°C and held at that temperature for 30 minutes to melt the mixture.

Thereafter, the melt was gradually cooled and solidified at a cooling rate of 2°C/min to obtain a 4-shaped crystal. When a part of the turtle-shaped crystal was collected and subjected to powder X-ray diffraction measurement, it was found that Bi 12GeO
It was confirmed that it was a γ quasicrystal of zo.

Example 2 A nickel plate was placed horizontally in an electric furnace and heated to 950°C in air.
BizzGe by heating to °C and holding at that temperature for 15 minutes.
The O2o powder was melted. Thereafter, the melt was slowly cooled at a cooling rate of 2°C/min to solidify and form a thin plate-like crystal on the nickel plate. The lamellar crystals had relatively flat surfaces and a thickness of about 0.5 mm.

In addition, the thin plate-like crystals were firmly attached to the nickel plate.

When a part of the thin plate-like crystal was collected and subjected to powder X-ray diffraction measurement, it was confirmed that it was a γ quasicrystal of B112Geo20. In this way, the nickel plate and the thin plate-like γ of Bi 12Geo2o firmly attached to the nickel plate
A composite body consisting of a quasicrystal, that is, an electrophotographic photoreceptor was obtained.

Example 3 587.4.9 Bi was placed in the same nickel crucible as Example 1.
A mixture of 20a and 12.6.9 5IO2 was charged.

This crucible was placed in an electric furnace, heated to 920° C. in air, and maintained at that temperature for 30 minutes to melt the mixture. Thereafter, the melt was gradually cooled and solidified at a cooling rate of 2° C./min to obtain a small turtle-shaped crystal. When a part of this diamond-shaped crystal was collected and subjected to powder diffraction measurement, it was found that B i 12siO
z.

It was confirmed that it was a γ-type crystal.

Example 4 On the same nickel plate as in Example 2, 4 g of Bi 12sio2° amorphous powder was placed. This nickel plate was placed horizontally in an electric furnace, heated in air to 920°C, and kept at that temperature for 15 minutes to melt the B11z5iO2o powder. Thereafter, the melt was slowly cooled at a cooling rate of 2° C./min to solidify and form a thin plate-like crystal on the nickel plate.

The lamellar crystals had relatively flat surfaces and were approximately 0.5 myrt thick. In addition, the thin plate-like crystals were firmly attached to the nickel plate. When a part of the thin plate-shaped crystal was collected and subjected to powder X-ray diffraction measurement, it was found that B1
It was confirmed that it was a γ-type crystal of 12SiOzo. In this way, a composite consisting of the nickel plate and the thin plate-like γ-type crystal of Bix28iOzo firmly adhered to the nickel plate, that is, an electrophotographic photoreceptor was obtained.

31- 127-

Claims (8)

[Claims] (1) The composition formula is 1xMOn (where M is at least one of kermanium, silicon, titanium, gallium, and aluminum)
The seed is a number, and X is a number that satisfies the condition 10≦X214, and n is the above M and X? ′ indicates the number of oxygen atoms determined stoichiometrically)
1. A method for producing a photoconductive material, which comprises cooling and solidifying the composite oxide into a γ quasicrystal by contacting it with nickel. (2) Claims characterized in that the molten liquid is placed in a heat-resistant container whose inner surface is made of nickel, and the molten liquid is cooled and solidified to form the γ quasicrystal. 2. A method for producing a photoconductive material according to item 1. (3) The molten liquid is placed in the cup-shaped or box-shaped heat-resistant container with a relatively deep bottom, and the molten liquid is cooled, swelled, and solidified to form the lump-like γ quasicrystal. A method for producing a photoconductive material according to claim 2, characterized in that: (4) A patent characterized in that the molten liquid is placed in the heat-resistant container with a very shallow bottom, and the molten liquid is cooled and solidified to form the r-type crystal in the form of a thin plate. A method for producing a photoconductive material according to claim 2. (5) the molten liquid is placed on a nickel surface of a conductive substrate at least one surface of which is made of nickel;
Production of the photoconductive material according to claim 1, wherein the melt is cooled and solidified to form the thin plate-like r-type crystal on the nickel surface of the conductive substrate. Method. (6) The photoconductive material according to any one of claims 1 to 5, wherein M in the composition formula is one or both of kermanium and silicon. manufacturing method. (7) M in the above composition formula is kermanium, and X is 12
7. The method for producing a photoconductive 1-O material according to claim 6, wherein n is 20. (8) M in the above composition formula is silicon, X is 12,
7. The method for producing a photoconductive material according to claim 6, wherein n is 20.