JPS60119571A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve the current rectifying characteristic between a base body and a photoconductive layer by providing an intermediate layer consisting of a thin amorphous Ni-B film or thin Ni-B alloy film between a conductive base body and the photoconductive layer. CONSTITUTION:An intermediate layer 2 consisting of a thin amorphous Ni-B film or thin Ni-B alloy film is formed by an electroless plating method, vapor deposition method, sputtering method, etc. on a conductive base body consisting of aluminum or the like. A photoconductive laye 3 consisting of Se, SeTe, etc. is then formed on the layer 2 to manufacture an intended electrophotographic sensitive body. The efficiency of hole implantation from the base body 1 is considerably increased by the presence of the Ni-B intermediate layer 2 without spoiling the electrostatic characteristic of the layer 3 and therefore the characteristic required for a composite photosensitive body for two-color copying is substantially satisfied. The layer 2 is easily industrially formable if an electroless plating method is used.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a two-color electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having a conductive substrate surface coated with a Ni-B non-quality or alloy thin film.

[Prior art]

Conventionally, it has been known to provide an intermediate layer between a conductive substrate and a photoconductive layer to facilitate the movement of carriers from the substrate side. Among these types of intermediate layers, a method has been proposed to improve the carrier injection property by using an IJi-P alloy as an intermediate layer, paying particular attention to the relationship between the work function and the photoconductive layer. See Publication No. 35864》. However, the negative charging characteristic of a photoreceptor with a Ni-P alloy as an intermediate layer on a substrate and a photoconductive layer made of AS2Se3 on top of it is less than -200V, and hole injection is sufficient. do not have. Also, if the work function is less than the photosensitive layer material, N
It has been proposed to use an intermediate layer made of one or more metals, a chalcogen substance of Te or more, a powder of A8 or more, and a binder resin (see Japanese Patent Publication No. 54-36859). However, since this method uses a binder resin, As
A photoconductive layer made of 2Se3 or the like has a disadvantage in that the formation conditions are restricted and satisfactory electrical properties cannot be obtained.

〔the purpose〕

The present invention has been made in view of the above-mentioned current situation, and its purpose is to improve the rectification characteristics between the substrate and the photoconductive layer of an electrophotographic photoreceptor.

〔composition〕

In order to achieve the above object, the present invention provides an N1-B amorphous thin film or a N1-B amorphous thin film as an intermediate layer in an electrophotographic photoreceptor.
The purpose is to use an alloy thin film.

The electrophotographic photoreceptor of the present invention is an N1-B amorphous thin film or an N
Basically, a photoconductive layer is provided on the surface of a conductive substrate coated with a 1-B alloy thin film. In another embodiment of the electrophotographic photoreceptor of the present invention, the photoconductive layer can have a two-layer structure of a first photoconductive layer and a second photoconductive layer. A first photoconductive layer is disposed on a conductive substrate surface coated with an N1-B amorphous film or a N1-B alloy thin film, and a second photoconductive layer is disposed on the first photoconductive layer. Further, the second photoconductive layer is sensitive to some chromatic light in the visible light range and transmits other chromatic light, while the first photoconductive layer is sensitive to at least the second photoconductive layer. It is sensitive to chromatic light that passes through the layer.

Next, the electrophotographic photosensitive pressure of the present invention will be specifically explained with reference to the drawings.

As shown in FIG. 1, the electrophotographic photoreceptor of the present invention has an intermediate layer 2 on a conductive substrate 1, and a photoconductive layer 3 on top of the intermediate layer 2.
The basic configuration is as follows. Examples of the conductive substrate include metal plates such as Al and stainless steel, and 5n02.
, In2O5, or other metal oxides, or plastic films, paper, or cloth coated with these metals or metal oxides can be used. The intermediate layer consists of a Ni-B amorphous thin film or an N1-B alloy thin film. The intermediate layer can be formed by conventional methods such as vapor deposition and sputtering, but electroless plating is industrially most advantageous. The thickness of the intermediate layer is in the range of 500A to 10μ, preferably 1μ to 5μ. For example, when using an alkaline nickel plating solution, the reduction and precipitation reaction of N1-B can be expressed by the following reaction formula.

4NiCt2 +NaBO2+ 8NaOH-+4Ni
+NaBO2+ 8NaC4+ 6H204NiC1
2+2NaBH4+6NaOH→2Ni2B+H2,,
+l8NaCl+, 6H20 The structure of the obtained N1-B film is amorphous, but even if it is amorphous, the rectification properties are greatly improved and desired electrical characteristics can be obtained. After plating, N1
When the -B film is post-treated, it becomes a Ni-B alloy, which maintains the same rectification properties as an amorphous film, improves adhesion to the conductive substrate, and releases stress in the N1-B film. It becomes possible to achieve this goal. Furthermore, a Se-based photoconductive layer can be used as the photoconductive layer, and a typical example thereof is Se%5eT
Examples include As2Se3.5e-Bi, 5e-8b, etc.

FIG. 2 shows another embodiment of the electrophotographic photoreceptor according to the present invention, in which an intermediate layer 2 is provided on a conductive substrate 1, and a first photoconductive layer 4 and a second photoconductive layer are further provided thereon. 5. The first photoconductive layer is S like the above photoconductive layer.
The e-type photosensitive layer has a thickness in the range of 10 to 150 microns, preferably 50 to 120 microns. Further, as the second photoconductive layer, a photoconductive member is used which becomes a conductor with a portion of chromatic light in the visible light region under positive or negative charging or bipolar charging. In particular, materials that exhibit photoconductivity under bipolar charging include phthalocyanine pigments, organic pigments such as azo pigments, pyrylium dyes, and eutectic complexes and charge transfer complexes of these dyes and resins.

That is, the second photoconductive layer is made of a material that has potential retention ability when subjected to positive or negative corona charging, and has the property of becoming a conductor with light of a specific wavelength. Further, the second photoconductive layer may be a single layer as shown in FIG. 2, but is not particularly limited to this, and as another embodiment of the present invention, as shown in FIG. It is also possible to have two layers, ie, a charge transport layer 7 and a charge transport layer 7. In the case of a single layer, the thickness of the second photoconductive layer is suitably about 5 to 60 μm.

In the case of two layers, it is appropriate that the charge generation layer has a thickness of about 0.1 to 5μ and the charge transport layer has a thickness of about 5 to 50μ. In the present invention, a new layer may be provided between the first photoconductive layer and the second photoconductive layer to improve functionality such as preventing charge leakage.

When a binder is used to form the second photoconductive layer, examples of the material include polyethylene, polystyrene,
Resins such as polyester, polyamide, polycarbonate, epoxy, urethane, silicone, and alkyd can be used. Plasticizers can be used together with binders, but
The appropriate amount of addition is 3 layers by weight % i based on the binder. As the plasticizer, those commonly used as plasticizers for resins, such as dibutyl phthalate and dioctyl phthalate, can be used as they are.

〔Example〕

The present invention will be further explained below with reference to Examples along with Comparative Examples, but the present invention is not limited thereto.

Example 1 Inventive product-1 with N1-B intermediate layer provided.

Three types of samples were prepared, one with a conventional N1-P intermediate layer (comparative product A-1) and one without an intermediate layer (comparative product B-1), and the injectability of carriers from the substrate was compared. The sample preparation method and characteristic values are shown below.

After degreasing an aluminum plate with a smooth surface using a nickel-boron electroless bath, WMF-15
N1 and B with a film thickness of about 1 μm were deposited on an Al plate using P (manufactured by World Metal Finishing Co., Ltd.). The obtained N1-B film was washed with hot water, dried, and then heat-treated at 350° C. for 6 hours. Thereafter, an As2Se3 photoconductive layer was formed on the Ni--B intermediate layer by vacuum evaporation to obtain a product of the present invention. The deposition conditions were: substrate temperature 200°C, degree of vacuum 2-5 x 10-'
Torr, boat temperature 470℃, deposition rate 1μ7mi
n and a film thickness of 60 μm.

For comparative product A-, an aluminum plate similar to the product of the present invention was degreased with trichlene and then soaked in a Nick Rulin electroless bath.
(manufactured by Nippon Kanigen) to precipitate Ni and P to a thickness of about 1 μm on an Al plate, and the resulting N1-P film was washed with hot water, dried, and then heat-treated at 50° C. for 6 hours. Thereafter, an A32Se3 photoconductive layer was formed on the comparative product A- in exactly the same manner as the present invention product.
It was set as i.

Comparative product B- was prepared by using an aluminum plate similar to the present invention product-1 after degreasing with trichlene, and then forming an As28e3 photoconductive layer on the Al plate in the same manner as the present invention product-1.

The positive and negative charging potentials of the products of the present invention and comparative products produced by the method described above were measured using EPA (manufactured by Kawaguchi Electric). However, the positive corona charge was set to +5 KV, and the negative corona charge was set to -5 KV. The measurement results are shown in Table 1 below.

Table 1 From the above results, it can be seen that the product of the present invention having the Ni-B intermediate layer has greatly improved hole injection efficiency compared to the conventional product (comparative product).

Example 2 Invention product-1 produced in Example 1, comparative products A-1 and B-1 t-nitrocellulose 4tt fat (manufactured by Shadow Co., Ltd.)
Each As2Se was immersed in a 10 weight percent solution of
3. An intermediate layer of 1 μm made of nitrocellulose resin was formed on the first light guide layer. Afterwards, this intermediate layer is coated with 5
A charge generation layer for the eTe second photoconductive layer was formed. The deposition conditions were alloy composition 8eTe 8vt%, C125ppm, substrate temperature 80°C, degree of vacuum 2-5X 10-6 Torr,
Boat temperature: 320°C, deposition rate: 5 u/min, film thickness: 5
It was set to μ. Further, a 5% by weight methylene chloride solution of polyvinylcarbazole was applied and dried on the 5eTe charge generation layer to form a charge transfer layer for the second photoconductive layer with a film thickness of 20μ. 2 and B-2 were obtained. Next, each of these photoreceptors was subjected to a primary corona charge of -5.7 KV, and then a secondary corona charge of +5.5 Kv, and then subjected to three steps: (1) No exposure, (2) Exposure through a red filter, and (2) White exposure. When the potential was measured, the results shown in Table 2 below were obtained.

Table 2 It can be seen that the difference in potential between the red dots between the inventive product and the comparative product in this table corresponds to the negative charging potential difference in Example 1.

Therefore, it can be concluded that the presence of the N1-B intermediate layer of the present invention improves the hole injection properties of the substrate and makes it possible to increase the potential of the red portion of the two-color photoreceptor.

〔effect〕

The electrophotographic photoreceptor of the present invention constructed as described above greatly increases the injection efficiency of holes from the substrate without impairing the electrostatic properties of the photoconductive layer due to the presence of the Ni-B intermediate layer. be able to. Therefore, the required characteristics of a post-mixing photoreceptor for two-color color copying are fully satisfied, and the N1-B intermediate layer can be easily formed industrially by the known electroless plating method.

[Brief explanation of the drawing]

1 to 3 are cross-sectional views showing examples of the layer structure of an electrophotographic photoreceptor according to the present invention. DESCRIPTION OF SYMBOLS 1... Conductive substrate, 2... N1-B intermediate layer, 3...
- Photoconductive layer, 4... First photoconductive layer, 5... Second photoconductive layer, 6... Charge generation layer, 7... Charge transport layer. Patent applicant Rico Co., Ltd. −

Claims (1)

[Scope of Claims] 1) An electrophotographic photoreceptor, characterized in that a photoconductive layer is provided on the surface of a conductive substrate coated with an N1-B amorphous thin film or an N1-B alloy thin film. 2) A first photoconductive layer and a second photoconductive layer are provided in this order on the surface of a conductive substrate coated with an N1-B amorphous thin film or an N1-B alloy thin film, and the first photoconductive layer is The second photoconductive layer is sensitive to at least chromatic light that passes through the second photoconductive layer, and the second photoconductive layer is sensitive to some chromatic light in the visible light range and transmits other chromatic light. An electrophotographic photoreceptor with all the following characteristics. 3) The second photoconductive layer includes a charge generation layer and a charge transport layer.
The electrophotographic photoreceptor according to claim 2, characterized in that it consists of a layer.