JP2663666B2 - Organic photoreceptor for electrophotography - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic photoconductor for electrophotography, and more particularly, to a material of a conductive substrate thereof.

[Conventional technology]

Conventionally, inorganic materials such as selenium, zinc oxide and cadmium sulfide have been used as photoconductive materials for electrophotographic photoreceptors. In recent years, organic photoconductive materials have attracted attention as alternatives to these inorganic materials, and are being developed.

Organic photoconductive materials have many advantages such as film-forming properties, light-transmitting properties, and thermal stability. However, sensitivity, mechanical strength (abrasion resistance, hardness, etc.), and chemical stability (light, ozone, etc.) (Durability). Therefore, by adopting a function-separated type laminated structure, organic photoconductors with improved sensitivity and durability have been developed and put into practical use. In recent years, optical printers have been widely used for small machines.

Organic photoreceptors generally have a charge generation layer on a conductive substrate,
It has a function-separated type laminated structure including a photosensitive layer in which charge transport layers are sequentially laminated. As a material for the conductive substrate, an Al-Mn-based Al alloy is usually used because of its advantages such as light weight and machinability. Further, in the photoreceptor having the above-described structure, since the conductive substrate and the charge generation layer are in contact with each other, charge leakage from the substrate to the charge generation layer occurs, and an image defect occurs when used in an optical printer. In order to prevent this, an alumite layer is formed on the surface of the substrate, and a charge generation layer is provided thereon.

[Problems to be solved by the invention]

However, a substrate made of an Al-Mn-based Al alloy has a disadvantage that the machinability is good but a high-quality alumite layer cannot be obtained. The Al-Mn-based Al alloy contains a large amount of crystalline material, and the size of the crystalline material is large, up to 10%.
Because it is about μm, the crystalline material dissolves in the acidic solution in the alumite process, and then becomes a hole, so that many large holes are formed. For this reason, in a conventional photoreceptor using a substrate made of an Al-Mn-based Al alloy, it is not possible to appropriately suppress the leakage of electric charge from the substrate to the charge generation layer, and the resulting image has an electric charge. A defect caused by the leak was generated.

Originally, if the substrate only needs to form an alumite layer, a uniform alumite layer can be obtained by using Al having a purity of about 99.9% instead of an Al alloy. However, in order to obtain a photoreceptor with good durability and good quality images, the surface of the photoreceptor should have a maximum height Rmax of 0.2 μm to 1.0 μm before forming the alumite layer, and the center line Average roughness Ra
0.03μm ~ 0.20μm at relative load curve cutting depth
With relative load length tp% (Depth 0.3μm) at 0.3μm
It is necessary to finish the surface to a very smooth surface of 45% to 70%. If the purity of Al is about 99.9%, the workability is poor, and the surface roughness described above cannot be obtained. For this reason, in a photoreceptor using such a substrate made of Al, an image defect occurs due to a surface defect of the substrate, and the adhesion between the substrate and the charge generation layer is poor, and the durability is poor. Problems arise.

The present invention has been made in view of the above-described problems, and by using a material of the conductive substrate as an Al alloy having a specific appropriate composition, an image with good image quality can be obtained, and durability can be improved. The object of the present invention is to provide an organic photoreceptor excellent in the above.

[Means for Solving the Problems] According to the present invention, there is provided a photosensitive layer in which a charge generation layer containing an organic photoconductive material and a charge transport layer are sequentially laminated on a conductive substrate. Wherein the conductive substrate contains 0.01% by weight or more of Si.
0.08 wt% or less, Mg 0.65 wt% or more and 0.95 wt% or less, Fe
Can be solved by providing an organic photoconductor for electrophotography composed of an Al alloy containing each in the range of 0.01% by weight or more and 0.05% by weight or less.

[Action]

The above Al alloy has good machinability and is included
The dispersibility of Si, Mg, and Fe is very good, and the amount of crystalline substances is extremely small. The surface of such a base made of an Al alloy can be processed to an extremely smooth and appropriate roughness, and a uniform alumite layer with few holes can be formed on the surface. Therefore, by using such a base, an image of good image quality can be obtained, and
It becomes possible to obtain an organic photoreceptor having excellent durability.

The surface roughness of the substrate is 0.2μm to 1.0μm at Rmax, 0.03μ at Ra
It is preferable that m is 0.20 μm and tp% (Depth 0.3 μm) is in the range of 45% to 75%. The thickness of the alumite layer formed on the surface of the substrate is preferably in the range of 1 μm to 12 μm.

〔Example〕

With respect to the base composed of Al alloys A, B, C, and D having the respective compositions shown in Table 1, the surface roughness of the surface was 0.2 μm to 1.0 μm in Rmax,
0.03 μm to 0.20 μm for Ra, 45% for tp% (Depth 0.3 μm)
The workability was evaluated by performing processing to make it 75%. In addition, the degree of crystallinity dispersion was examined, and the quality of the layer was examined by forming an alumite layer on the surface.

Next, a charge generation layer and a charge transport layer made of an organic material were sequentially formed and laminated on each substrate on which the above-described roughening treatment was performed and the alumite layer was formed to form a photosensitive layer, thereby obtaining a photosensitive member. . At this time, the film formation conditions such as wettability, smoothness, and adhesion, and the electrical characteristics of the obtained photoreceptor were examined, and printing was performed using a commercially available optical printer to evaluate the image quality.

Table 1 shows the results of these evaluations, the results of the investigations, and the results of the comprehensive judgments, corresponding to the Al alloy.

From Table 1, it can be seen that a substrate made of an Al alloy having a composition A is suitable for obtaining a photoreceptor excellent in both characteristics and productivity, and a substrate made of an Al alloy having a composition C is almost satisfactory.

0.01% to 0.08% by weight of Si, 0.65% to 0.95% of Mg
By using an Al alloy containing 0.01% to 0.05% by weight of Fe and 0.01% to 0.05% by weight of Fe, the surface of the substrate can be reduced to an Rmax of 0.2%.
μm to 1.0 μm, 0.03 μm to 0.20 μm in Ra, tp% (Depth 0.3
μm), it is possible to form a very smooth and fine surface roughness of 45% to 70% and to form a smooth and uniform alumite layer with a film thickness of 1 μm to 12 μm on the substrate surface. In this way, it is possible to uniformly form a photosensitive layer made of an organic material with good adhesion, to obtain an image of good image quality, and to produce an organic photosensitive member having excellent durability with high productivity. Become like

〔The invention's effect〕

According to the present invention, the material of the conductive substrate used for the organic photoreceptor is composed of 0.01 to 0.08% by weight of Si and 0.65% by weight of Mg.
0.95% by weight or more, Fe 0.01% or more 0.05% by weight
By using the Al alloy contained below, the surface of the substrate can be processed to an appropriate surface roughness, and a good alumite layer can be formed on the surface of the substrate, resulting in good image quality and excellent durability. An organic photoreceptor for electrophotography can be obtained.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-64-79339 (JP, A) JP-A-1-285953 (JP, A) JP-A-1-213664 (JP, A) JP-A-64-79 86151 (JP, A) JP-A-64-86152 (JP, A) JP-A 64-86155 (JP, A) JP-A-1-123245 (JP, A) JP-A-1-180936 (JP, A) JP-A-61-177347 (JP, A)

Claims (1)

(57) [Claims] 1. An electrophotographic organic photoreceptor comprising a photosensitive layer in which a charge generation layer containing an organic photoconductive material and a charge transport layer are sequentially laminated on a conductive substrate. Substrate contains 0.01% to 0.08% by weight of Si and 0.6%
An organic photoconductor for electrophotography, comprising an Al alloy containing 5 wt% to 0.95 wt% and Fe in a range of 0.01 wt% to 0.05 wt%.