JPS62278565A - Selenium-tellurium material for electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body having uniform characteristic value by regulating the atomic concn. of oxygen in an SeTe alloy as starting material to be evaporated to form an SeTe layer to prescribed ppm. CONSTITUTION:An Al pipe coated with an Al2O3 layer or a PET insulating layer, a laminate consisting of PET, Al, an electron injection preventive layer and a charge transferring layer of PVK or the like is used as a substrate. This substrate is placed in a vacuum deposition apparatus and an SeTe alloy having a prescribed O2 content is weighed and set as starting material to be evaporated. The apparatus is evacuated to a prescribed degree of vacuum and electric current is supplied to a resistance heating and evaporating source to evaporate the SeTe alloy. After a film is deposited to a prescribed thickness, the supply of electric current is stopped. Thus, a desired SeTe film is formed on the substrate.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a selenite material for photoreceptors used in electrophotography.

[Prior Art] With the demand for higher sensitivity of electrophotographic photoreceptors, efforts have been made to achieve the objective by mixing various sensitizers.
When forming a photosensitive layer by vapor deposition, the composition of the evaporation source changes over time due to differences in vapor pressure, atomic weight, etc. of the constituent components, and the composition of the film changes accordingly. There are inconveniences. This inconvenience, for example, increases the defective rate due to increased product variation in photoreceptors and requires resetting copying conditions when replacing photoreceptors, causing a significant increase in costs. In order to improve these inconveniences, many proposals regarding evaporation methods have been made, but no definitive improvement has yet been achieved.

[Problem to be solved by the invention 1] The present invention uses a conventional resistance heating type evaporation source and a complicated device.
When a selenium tellurium photosensitive layer is formed by vacuum evaporation without using a method, variations in the characteristic values of a photoreceptor, specifically acceptance potential, dark decay, photosensitivity, etc., are reduced, and the defective rate of the product is reduced. The purpose of this invention is to provide a selenium tellurium material.

[Means for Solving the Problems] The present inventors have made extensive efforts regarding materials in addition to vapor deposition techniques regarding electrophotographic photoreceptors whose photosensitive layer is selenium telluride (SeTe), which is the most common material used to achieve high sensitivity. As a result of research, it has been clarified that the above-mentioned disadvantages occur when the solubilization strength contained in the SeTe alloy used as the photosensitive layer is larger than the value. In other words, as the oxygen concentration changes,
It was discovered that the Se/Te composition in the thickness direction of the deposited film changes significantly, which in turn causes a significant change in the product variation of photoreceptors, and based on this knowledge, the present invention was completed.

That is, the present invention relates to an electrophotographic photoreceptor having a 5eTe layer as a photosensitive layer on a conductive support.
It is characterized in that the concentration of oxygen atoms contained in the 3eTe alloy, which is necessary in the base material before evaporation to form the layer, is 1001)13m or less, preferably 1 oppm or less.

The details of the invention are described below.

Examples of conductive supports used in electrophotographic photoreceptors include AI, Mo, Au, in, Nb, Ta,
A conductive support made of a metal such as Ni, V, Ti, Pt, Pd, Cr, PB, or an alloy thereof, and in the case of an insulating support, as necessary, for example, in the case of PET or polyimide film. A film in which a thin film of the above conductive material is formed on the film is used. Other examples of the conductive material to be made into a thin film include n203, SnO2, CuI, and the like.

The shape of the support may be cylindrical, flat, sheet, screen, or the like.

On the above support, as a structure of the electrophotographic photoreceptor, a charge injection layer, a charge injection blocking layer, a charge transport layer, an insulating layer, a surface layer, a protective layer are formed according to the electrostatic latent image forming process or the characteristics of the materials used. etc. are laminated functionally so that an electrostatic latent image is formed.

The structure of the electrophotographic photoreceptor requires a photosensitive layer (hereinafter abbreviated as charge generation layer) in addition to the above-mentioned layers.

The present invention relates to the material of this charge generation layer. The substrate used has a layered structure that provides the desired function. For example, AI treated with Al2O3
A pipe, a PET insulating layer, a conductive film such as NiCr or AI formed on PET, and a stacked charge transport layer such as PET-A I-electron injection blocking layer-PVK are used.

These substrates are placed in a vacuum evaporation equipment tank, and 5eTe raw material is weighed and set so as to have the 02 content as intended by the present invention as an evaporation source.

That is, high-purity Se and Te and TeO2 are weighed and set so as to have the desired content, and the inside of the tank is evacuated.

After evacuation to a predetermined degree of vacuum, for example 1×10 −5 Torr, electricity is applied to the resistance heating evaporation source to evaporate the 5eTe raw material. After obtaining a predetermined film thickness, the current supply is stopped and a desired 5eTe film is formed on the substrate.

Note that the method for producing 5eTe material of the present invention is not limited to the above example, and for example, the system may be thoroughly created with a non-oxidizing atmosphere or a reducing atmosphere may be actively created (q.
It may be an eTe alloy, and is not limited by the manufacturing method.

After the desired 5eTe alloy material layer is formed, an electrophotographic photoreceptor is fabricated with or without laminating other layers necessary to form an electrostatic latent image.

:! Example 1 The 5eTe material of the present invention will be described below based on an example with reference to the drawings.

Example 1 After vacuum sealing 99,999% se and 99.9999% Te in a Pyrex ampoule, 55%
Mixed for 2 hours at 0'C. Thereafter, a 5eTe alloy containing 40% by weight of Te was obtained.

This alloy was finely pulverized and a tablet-shaped 5eTe material having an diameter of 8 and a thickness of 2 # was produced using a pressure molding machine. The substrate is an A1 pipe 2 which has been subjected to Al2O3 treatment in the vacuum device 1 shown in FIG.
The substrate temperature was raised to 75°C.

The thickness of the film formed on the substrate in the resistance heating evaporation source 3 is 50μ.
It was filled with Se weighed so that The above-mentioned 3e'l'-e material was weighed and set in the resistance heating evaporation source 4 so that the thickness of the film formed on the substrate was 1 μm.

After evacuating the tank and reaching 1 x 1'Q-5 Torr, the evaporation source 3 was energized, and the temperature was raised to 350'C by a control system (thermocouple) not shown, and held for 20 minutes. Se
was formed on a substrate to a thickness of 50 μm. After that, the evaporation source 4 is energized in the same way, and a control system (thermocouple) not shown is used to energize the evaporation source 4.
The temperature was raised to 50'C and maintained for 3 minutes to form a film of 5eTe to a thickness of 1 μm on the substrate. Thereafter, the electricity supply was stopped and the pressure inside the tank was returned to atmospheric pressure, thereby obtaining an electrophotographic photosensitive plate having the structure shown in FIG. 2. The same operation was repeated five more times to obtain six samples.

Example 2 99.999% Se, 99.9999% Te and TeO2
was weighed so that the oxygen atomic ratio was 10 ppm, vacuum-sealed in a Pyrex ampoule, and then heated in a shaking oven.
Mixed for 2 hours at 0°C. Thereafter, a 5eTe alloy containing 40% by weight of Te and an atomic ratio of oxygen of 10 pDm was obtained. An electrophotographic photosensitive plate was prepared in exactly the same manner as in Example 1 except that this material was used.

Example 3 99.999% Se, 99.9999% Te and TeO2
was weighed so that the oxygen atomic ratio was 1100 pp, vacuum sealed in a Pyrex ampoule, and then heated in a shaking oven for 5
Mixed for 2 hours at 50'C. After that, an urgent order was made and Te40
1q of 5eTe alloy with weight% and oxygen atomic ratio of 1100pp. An electrophotographic photosensitive plate was obtained in exactly the same manner as in Example 1 except that this material was used.

Example 4 Same as Example 2.3, containing oxygen atomic ratio 1.000p
A 5eTe alloy (Te40@mass%) of pm was obtained. An electrophotographic photosensitive plate of 1 q was prepared in exactly the same manner as in Example 1 except that this material was used.

Example 5 In the same manner as in Example 4, Te was 40% by weight and the oxygen atomic ratio was 10. A 5eTe alloy of OOOppm was obtained. An electrophotographic photosensitive plate was prepared in exactly the same manner as in Example 1 except that this material was used.

As described above, the electrical characteristics of the electrophotographic photosensitive plates described in Examples 1 to 5 were measured, and the dark area potential as shown in FIG.
The photosensitivity shown in FIG. 3(b) was (q). In the figure, the black circles indicate the average value of six electrophotographic photosensitive plate samples.

As is clear from Figures 3 (a) and (b), when the atomic concentration of oxygen exceeds 100 ppm, the charging properties of the dark potential become poor and there are many variations, and some samples were not charged at all. . In addition, the photosensitivity began to vary significantly when it exceeded 1oopp.

On the other hand, 5eTe containing 10.000 ppm of oxygen showed comparatively stable characteristics in terms of dark potential and photosensitivity, but had the disadvantage that photosensitivity at long wavelengths decreased.

[Effects of the Invention] The present invention provides a selenium tellurium material for electrophotographic photoreceptors, which has an oxygen atom of 9 degrees and 1100 pp or less. Electrophotographic photoreceptors with less variation in characteristic values can be easily manufactured.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of a vacuum evaporation device, Figure 2 is a sectional view of an example of an electrophotographic photoreceptor, and Figure 3 (a).
FIG. 3B is a diagram showing the relationship between the atomic ratio of oxygen contained and the dark potential, and FIG. 3(b) is a diagram showing the relationship between the atomic ratio of oxygen contained and photosensitivity at 80 Q nm. Symbols in the figure: 1... Vacuum evaporation device; 2... Substrate; 3, 4...
・Evaporation source. Figure 1 Figure 2 Figure 3 (,l) 0 10 TOO1α℃ 1@M acid p+single ppm Containing Nansho KyoJGiangosunhi ppm

Claims (1)

[Claims] A selenite material for a photosensitive layer of an electrophotographic photoreceptor formed on a conductive support by vapor deposition, the selenite material having an oxygen atom concentration of 100 ppm or less.