JPS63292149A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body high in image quality and durability by forming an interlayer made of a silicone resin containing specified amount ranges of Si, O, C, H and N. CONSTITUTION:The electrophotographic sensitive body is obtained by successively laminating a photosensitive layer, the interlayer containing 50-88wt.% Si and O, 10-30wt.% C, 1-10wt.% H, and 1-10wt.% N of the total weight of the interlayer, and a protective layer on a conductive supporting body. The interlayer may be formed in an optional thickness, but it is preferred to set it to <=5mum, much preferably, <=1mum, especially, <=0.5mum, and it is formed by the coating method, such as dip coating or spray coating, thus permitting the obtained photosensitive body to have the interlayer superior in environment resisting characteristics and high sensitivity, long durability, and high reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an electrophotographic photoreceptor, particularly to an improvement in an electrophotographic photoreceptor having a protective layer on the surface of a photoconductive layer.

[Prior Art] Conventionally, electrophotographic photoreceptors have been prepared by providing a photosensitive layer mainly made of selenium or selenium alloy on a conductive support, or by disposing an inorganic photoconductive material such as zinc oxide or cadmium oxide in a binder. Generally known are those using dispersed materials, those using organic photoconductive materials such as poly-N-vinylcarbazole and trinitrofluorenone or azo pigments, and those using amorphous silicon.

At present, Se-based photoreceptors, particularly 3e-AS-based (As2Se2) photoreceptors, are known as the most sensitive electrophotographic photoreceptors, but these include the following problems.

■ Because the Se layer on the surface of the photoreceptor is exposed,
During actual use, it is easy to get scratched due to paper jams, etc.

■ Abnormal images such as background smudges and image blurring occur due to the adsorption and contamination of special chemicals that exist within the copying machine (developers, cleaning materials, etc.) or in the environment in which it is used.

■ Similarly, during actual use, there is a risk that the Se layer will be rubbed by the paper, the cleaning section, the developing section, etc., and Se will adhere to or be discharged onto the copy.

(2) In particular, in the case of a 5e-As photoreceptor, the surface resistance is not sufficiently large if the film is directly deposited by vapor deposition, and the charging potential may be insufficient if the film is directly deposited.

As a method for eliminating such drawbacks, a technique is known in which a protective layer is provided on the surface of the photoreceptor.

Specifically, a method of providing an organic film on the surface of the photosensitive layer (
Japanese Patent Publication No. 3B-15446), method of providing an inorganic oxide (Japanese Patent Publication No. 43-14517), method of laminating an insulating layer with a contact layer (Japanese Patent Publication No. 43-27591), or plasma CVD method/photoCVD method A method of laminating a-3i layer, a-3i:N:H layer, a-3i:Q:H layer, etc. (JP-A-57-179859, JP-A-59-58)
437) has been disclosed.

However, the protective layer has a high electrophotographic resistance (10”Ω・
cm or more), problems arise such as an increase in residual potential and accumulation upon repeated use, which is not preferred from a practical standpoint.

A method of using a photoconductive layer as a protective layer as a technique to compensate for the above drawbacks (Japanese Patent Publication No. 48-38427, Japanese Patent Publication No. 43-16198)
, Special Publication No. 49-10258, USP-290
1348), Ho! A method of adding a transfer agent typified by the dye Yaruis acid to the J layer (Japanese Patent Publication No. 44-834, JP-A-53-133444), or a method of controlling the resistance of the protective layer by adding metal or metal oxide fine particles. (Unexamined Japanese Patent Publication No. 5
3-3338> etc. have been proposed.

However, in such a case, the protective layer absorbs light, reducing the amount of light reaching the photosensitive layer, resulting in a problem of lowering the sensitivity of the photoreceptor (so-called filter effect).

Furthermore, as proposed in JP-A-57-30846, by dispersing metal oxides with an average particle size of 0.3 μm or less in the protective layer as a resistance control agent, the protective layer can be made substantially transparent to visible light. The method is discussed, but in reality, there are many particles with a diameter of 0.3 μm or more, which causes absorption and scattering of visible light, reducing the sensitivity of the photoreceptor. In addition, a problem unique to photoreceptors having a protective layer containing fine particles is a decrease in resolution. 1 Photoreceptors with these protective layers show some improvement compared to those without a protective layer, but depending on the type of photosensitive layer, the adhesion between the protective layer and the photosensitive layer may decrease. There is a phenomenon in which the chargeability decreases.

As a means to improve these problems, it has been proposed to provide an intermediate layer between the storage layer and the photosensitive layer to improve adhesion or to prevent charge injection.

These intermediate layers include an intermediate layer containing an inorganic compound as a main component (JP-A-57-30843), an intermediate layer containing an organic polymer compound as a main component (JP-A-57-30).
844), an intermediate layer containing an organometallic compound as a main component (JP-A-58-6074B, JP-A-58-1216)
43, Japanese Patent Application Laid-open No. 58-121045), etc., but even if a good screen is obtained in low humidity, the resolution deteriorates in high temperature, and the technology that can solve all of these problems has not yet been completed. It has not been.

Purpose] The purpose of the present invention is to solve the above-mentioned problems of the prior art, provide high transparency and mechanical strength, and in particular provide a protective layer that is stable against changes in environmental conditions such as humidity. An object of the present invention is to provide an electrophotographic photoreceptor with high image quality and durability.

[Structure] In order to achieve the above object, the structure of the present invention is such that in an electrophotographic photoreceptor in which a photosensitive layer, an intermediate layer, and a surface protective layer are sequentially laminated on a conductive support, the intermediate layer is stacked on top of the entire intermediate layer. (a) Silicon and oxygen content: 50-aawt% (b) Carbon content: 10-30wt% (c) Hydrogen content: 1-10wt% (d) Nitrogen content: 1-10wt% This is an electrophotographic photoreceptor made of a silicone resin within the range of .

The photosensitive layer of the photoreceptor used in the present invention is 3e, 5e.
-Te, Se alloys such as AS23e3, ZnO, CdS,
Used are particles of It-Vl group compounds such as CdSe dispersed in resin, organic photoconductive materials such as polyvinylcarbazole, or a-3i.

There are no particular restrictions on the structure of the photosensitive layer, and it may be a single layer or a stack of a charge generation layer and a charge transport layer.

The photosensitive layer mainly composed of 3e-As used in the present invention is A
The composition of s, 3e atoms is AS: 0.1 to 45 wt%, S
e: within the range of 55 to 99.9 wt%, and this photosensitive layer may be a single layer or multiple layers. Further, the photosensitive layer may contain one or more elements of additives such as halogen, Te, 3b, and 3i in addition to As and 3e.

As a method for forming the photosensitive layer, an alloy containing As and 3e in an amount satisfying the above conditions may be prepared and vapor-deposited, or a single material or an alloy may be placed in a plurality of evaporation sources and co-evaporated.

The silicone resin used in the present invention has (1) an alkoxy group-containing polysiloxane (2) a hydroxyl group-containing polysiloxane (3) at least one amino group, imino group, or nitrile group bonded to a carbon atom and two or more alkoxy groups. 3
It consists of a composition whose main component is an organosilicon compound having individually bonded silicon atoms.

To form the intermediate layer of the present invention, a solution prepared by dissolving each of the above components in a suitable solvent such as ligroin or hexane may be applied onto the photoconductive layer and then dried or cured by heating.

The content of 3i and O in the hardened intermediate layer is in the range of 50 to 88 Wt based on the total amount of the intermediate layer, and the content of 01H and N is C: 10 to 30 wt%, respectively, based on the total amount of the intermediate layer.
It is necessary that H: 1 to 10 wt% and N: 1 to 10 wt%.

The thickness of the intermediate layer can be arbitrarily set, but it is preferably 5 μm or less, preferably 1 μm or less, particularly 0.5 μm or less. The intermediate layer can be formed by a dipping method, a spray method, or the like.

The protective layer used in the present invention is made of an organic polymer compound to which a suitable amount of a conductivity control agent such as an organic compound or an inorganic compound is added. Specifically, organic compounds include anionic, cationic, and nonionic organic electrolytes, and inorganic compounds include metals such as gold, silver, copper, nickel, and aluminum, zinc oxide, titanium oxide, tin oxide, and indium oxide. , and metal oxides such as tin oxide containing antimony oxide and tin oxide containing indium oxide,
Mixtures of these may also be used.

The film thickness is 0.5 to 30 μm, preferably 1 to 10 μm. If the thickness is less than 0.5 μm, the mechanical strength of the protective layer is weak and the wear resistance is low, making the protective layer ineffective for long-term use. If the thickness is more than 30 μm, charges will accumulate in the protective layer and Residual potential increases during use.

This retaining layer is formed by mixing or dispersing a resistance control agent in the silicone resin and applying the mixture by dipping or spraying onto the photoconductive layer, or by forming it into a film and then adhering it.

The specific resistance of the protective layer is 1 x 10'' to 1 x 10 Ωcm, preferably 1 x 1011 to 10 12
It's Ωcm. When the resistivity is less than 1×10I@Ωcm, the charge retention ability is low, image blurring occurs, and 'lXl0''ΩC
If it is 11I or more, the residual potential is large and background stains occur.

As the conductive support, a conductor or an insulator treated for conductivity is used. For example, AI, Ni, Fe5Cu,
A on an insulating substrate such as metal or alloy such as Au, polyester, polycarbonate, polyimide, glass, etc.
Metals such as I, AQ, AU or In2O, 5n0
Examples include those formed with a thin film of conductive material such as No. 2, and paper treated with conductive treatment.

Further, there are no particular restrictions on the shape of the conductive support, and plate-like, drum-like, or belt-like ones may be used as required.

Examples and comparative examples of the present invention will be shown below.

Example 1 After pre-treating (cleaning) an aluminum tube (aommφx 340mm1), it was placed in a vacuum lid @ device and AS2Se3 alloy was resistance heated vapor-deposited on the support under the following conditions so that the film thickness was 60 μm. A photoconductive layer was prepared by performing the following steps.

Vapor deposition conditions Vacuum degree: 3X 10-6 Torr Support temperature: 200°C Boat temperature: 450°C Next, an intermediate layer forming solution, that is, an alkoxy group-containing polysiloxane, a hydroxyl group-containing polysiloxane, and an amino bonded to a carbon atom, is deposited on the photoconductive layer. Silicon resin (AY42-441 manufactured by Toshi Silicone Co., Ltd.) glue groin solution (solid content 5%) whose main component is an organosilicon compound having a silicon atom with at least one group and 2 to 3 alkoxy atoms bonded
was applied to a film thickness of 12 μm, and heated at 100°C for 2
After drying for a while, an intermediate layer was prepared.

Styrene-methacrylic acid-acrylic acid-
N-methylol acrylamide resin liquid (solid content 4 owt
%) 30@ffi parts, 10 parts by weight of tin oxide powder containing antimony oxide towt, and an appropriate amount of solvent were added and dispersed in a ball mill for 72 hours.The dispersion was applied by dip coating and dried at 120°C for 30 minutes to give a protection of about 5μ. Layers were set up.

As a result of elemental analysis of the composition of the intermediate layer of this photoreceptor, the content of 3i and O 67.8wt%C content 22.7wt%H content
5.8wt%N content 3.7
It was wt%.

Comparative Example 1 A photoreceptor was produced in exactly the same manner as in Example except that the composition of the intermediate layer forming liquid was changed to the following.

Intermediate layer forming liquid Zirconium acetylacetonate double interlayer γ-methacryloxypropyltrimethoxysilane (KBM 503 manufactured by Shin-Etsu Chemical Co., Ltd.) 1 part by weight n-butanol 40 parts by weight Comparison with Example 1 obtained as above Regarding Example 1, the sensitivity (μJ/
Cm2) was determined and compared.

As shown in Table 1, it was found that the sensitivity of the photoreceptor according to the present invention did not decrease despite the provision of a protective layer.

Table 1 Example 2 A photoreceptor was produced under exactly the same conditions as in Example 1 except that the solid content in the intermediate layer forming liquid (ligroin solution) in Example 1 was changed to 30%.

The image characteristics of this photoreceptor and the photoreceptor of Comparative Example 1 were evaluated. The results are shown in Table 2 below.

Table 2 As shown in Table 2 above, under normal temperature and normal humidity, there was no difference in resolving power of 6 lines/mm for both the inventive product and the comparative product. However, under high temperature and high humidity conditions, the product of the present invention had a resolution of 6 lines/mm, which was rarely as good as the image at room temperature and humidity, whereas the comparative product had a resolution of 4 lines/mm, which caused noticeable blurring of the image compared to normal temperature and humidity. appeared.

As a result of a durability test of 300,000 copies made on the product of the present invention, no abnormal images were observed, and it showed good image characteristics as in the initial stage.

[Effects] As explained above, the intermediate layer of the photoreceptor of the present invention has superior environmental resistance compared to conventional intermediate layers, and provides photosensitive material with high sensitivity, durability, and reliability. You get a body.

Claims (1)

[Scope of Claims] In an electrophotographic photoreceptor in which a photosensitive layer, an intermediate layer, and a surface protective layer are sequentially laminated on a conductive support, the intermediate layer contains (a) silicon and oxygen relative to the total amount of the intermediate layer. (b) Carbon content is 10 to 30 wt%. (c) Hydrogen content is 1 to 10 wt%. (d) Nitrogen content is in the range of 1 to 10 wt%. An electrophotographic photoreceptor characterized by: