JPS5986060A - Electrophotographic light sensitive drum - Google Patents

Abstract

PURPOSE:To obtain a drum superior both in mechanical strength and electrostatically charging performance by forming a semiconductor type conductive ceramic layer same in polarity as the surface of a photoconductive layer to be conrona charged on the surface of a metallic drum by the flame coating method and forming a photoconductive layer contg. an amorphous Si on this layer. CONSTITUTION:A semiconductor type, such as N type SiC or P type ZnO, conductive flame sprayed ceramic layer 4 same in polarity as the surface of a photosensitive layer 2 to be corona charged is formed by flame coating on the surface of a metallic drum, especially Al drum 1, and the layer 4 is polished to smooth its surface. A photoconductor layer 2 contg. amorphous Si doped with P, B, or the like so as to give N or P type conduction is formed on the layer 4 to obtain a photosensitive drum 5. Injection of carriers 7 opposite in polarity to the charged surface of the layer 2 is intercepted by rendering the charged polarity 6 of the layer 2 surface same as the conduction polarity of the layer 4 and attenuation of charged potential of the layer 2 is suppressed. As a result, the obtained photoreceptor is kept superior both in strength of the drum and charging characteristics, even if the layer 2 is thinned.

Description

【発明の詳細な説明】 この発明は、極めて強靭な機械的強度を有する電子写真
用感光ドラムに関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic photosensitive drum having extremely high mechanical strength.

従来の電子写真用感光ドラムとして第１図に示スモのが
あった。図において、（１）はアルミニウムドラムであ
シ、その上に、プラズマＣＶＤ（Ｃｈｅｍｉｃａｌ　Ｖ
ａｐｏｕｒ　Ｄｅｐｏｓｉｔｉｏｎ　　）法あるいはス
パッタリング法等で３〜３０μｍ程度のアモルファス・
シリコン（以下α−８ｉ　　と称す）感光層（２）が形
成されており、これらによシ感光ドラム（５）が構成さ
れている。A conventional electrophotographic photosensitive drum is shown in FIG. In the figure, (1) is an aluminum drum, and a plasma CVD (Chemical V
An amorphous film of about 3 to 30 μm is formed by apor deposition method or sputtering method.
A silicon (hereinafter referred to as α-8i) photosensitive layer (2) is formed, and a photosensitive drum (5) is constituted by these layers.

そしてこの感光ドラム（５）では、α−８ｉ感光層（２
）の上で、通常のカールソン法の電子写真プロセスによ
シ静電潜像が形成され、２成分現像剤あるは、堆積速度
が遅いため通常１０μｍ以下の薄層で用いられる。In this photosensitive drum (5), the α-8i photosensitive layer (2
), an electrostatic latent image is formed by a conventional Carlson electrophotographic process, and a two-component developer is usually used in a thin layer of 10 μm or less because of its slow deposition rate.

従来の、α−８ｉを使う電子写真用感光ドラムは以上の
ように構成されているので、例えは鉄粉等が該ドラム異
面に圧接されると、α−８ｉ感光層（２）自体、は硬度
が高く機械的強度が優れているにもかかわらず、アルミ
ニウムドラム（１）自体が陥没するために簡単に上記α
−５ｉ感光層（２）が破壊されてしまう。更には上記α
−５ｉ感光Ｊ＠＋２＋が薄いため、アルミニウムドラム
（１）側から、α−８ｉ感光層（２）の表面帯％極性と
反対極性の電荷が注入され易く、所定の表面電位を得難
いという欠点があった。Since the conventional electrophotographic photosensitive drum using α-8i is constructed as described above, when iron powder or the like is pressed against the different surface of the drum, the α-8i photosensitive layer (2) itself, Although the aluminum drum (1) has high hardness and excellent mechanical strength, it easily collapses due to the aluminum drum (1) itself caving in.
-5i photosensitive layer (2) is destroyed. Furthermore, the above α
Since the -5i photosensitive J@+2+ is thin, charges with the opposite polarity to the surface band % polarity of the α-8i photosensitive layer (2) are easily injected from the aluminum drum (1) side, making it difficult to obtain a predetermined surface potential. there were.

この発明は上記のような従来のものの欠点を除去するた
めになされたもので、アルミニウムドラム上に光導電体
層表面のコロナ帯電の帯電極性と同極性の伝導型の導電
性溶射セラミック層を形成することにより、機械的強度
と帯電能力のいずれもがすぐれた電子写真用感光ドラム
を提供することを目的としたものである。This invention was made in order to eliminate the above-mentioned drawbacks of the conventional method, and it forms a conductive thermal sprayed ceramic layer of the same polarity as the corona charging polarity on the surface of the photoconductor layer on an aluminum drum. By doing so, it is an object of the present invention to provide an electrophotographic photosensitive drum that is excellent in both mechanical strength and charging ability.

以下この発明の一実施例を図について説明する。An embodiment of the present invention will be described below with reference to the drawings.

第２図はこの発明の一実施例による電子写真用感光ドラ
ムを示す。図において　（１）はアルミニウムドラム、
（４）はこのアルミニウムドラム（１）上に形成された
炭化シリコンあるいは酸化チタン等の導電性を有する溶
射セラミック層でちる。この溶射セラミック）＊　第４
１の表面は、平滑性を改善するだめに研磨処理され、そ
してその上にα−３ｉ感光層（２）がプラズマＣＶ　Ｉ
）法によシ形成されており、これらにより電子写真用感
光ドラム（５）が構成されている。この時、上記溶射セ
ラミック＃ｒｓ　（４）の厚みは０．１ｍ＋＋〜２叫程
度がよい。FIG. 2 shows an electrophotographic photosensitive drum according to an embodiment of the present invention. In the figure (1) is an aluminum drum,
(4) is a thermally sprayed ceramic layer having electrical conductivity such as silicon carbide or titanium oxide formed on the aluminum drum (1). This thermal sprayed ceramic) * 4th
The surface of 1 is polished to improve its smoothness, and an α-3i photosensitive layer (2) is deposited on it by plasma CV I.
) method, and these constitute an electrophotographic photosensitive drum (5). At this time, the thickness of the sprayed ceramic #rs (4) is preferably about 0.1 m++ to 2 m++.

このような本実施例によれば、上記感光ドラム（５）は
、鉄等に比べて充分硬度の高い溶射セラミック層（４）
上にα−５ｉ感光層（２）が形成されているため、鉄粉
あるいは他の固形物が上記感光ドラム（５）Ｋ衝突して
も基利自体が陥没することはなく、硬度は高いが脆いα
−５ｉ感光層（２）を安全に保持することができ、はは
セラミックに近い総合強度を有する従来にない極めて堅
牢なものとなる。According to this embodiment, the photosensitive drum (5) is made of a thermally sprayed ceramic layer (4) that is sufficiently hard compared to iron or the like.
Since the α-5i photosensitive layer (2) is formed on top of the photosensitive drum (5), even if iron powder or other solid objects collide with the photosensitive drum (5), the core itself will not cave in, and although the hardness is high, fragile α
The -5i photosensitive layer (2) can be safely held, and it is extremely robust, which has an overall strength close to that of ceramics.

更に、第３図の部分拡大図で示すようにこの実施例では
、感光ドラム（５）の帯電極性と導電性を有向保持能力
を高めることができる。即ち、第３図のようにα−３ｉ
感光層（２）上に負電荷（６）の帯電を行なう場合には
、Ｎ型の伝導型を示す炭化ンリコンの溶射セラミック層
（４）を用いると、該セラミック層（４）が帯電電荷（
６）の極性の負と反対極性の正のｔ荷担体（７）の感光
ドラム（５）表面への注入を阻止するために、上記α−
３ｉ感九層（２）上の負帯電宣布１（６）の減衰を抑え
ること力；できる。なお、同図において、溶射セラミッ
ク層（４）乃；形成されていない揚圧の注入電荷（７）
によシ負帯電電タデ（６）力ｘｉ肖減してしまう。この
ような注入阻止効果のある溶射セラミ改善されることが
認められた。Furthermore, as shown in the partially enlarged view of FIG. 3, in this embodiment, the ability to maintain the charged polarity and conductivity of the photosensitive drum (5) in a directional manner can be improved. That is, as shown in Figure 3, α-3i
When charging the photosensitive layer (2) with a negative charge (6), if a thermally sprayed silicon carbide ceramic layer (4) exhibiting N-type conductivity is used, the ceramic layer (4) will be charged with a negative charge (6).
In order to prevent the injection of the t-load carrier (7), which has a positive polarity opposite to the negative polarity of 6), onto the surface of the photosensitive drum (5), the α-
It is possible to suppress the attenuation of the negative charge declaration 1 (6) on the 3i-sensing nine layer (2). In addition, in the same figure, the thermal sprayed ceramic layer (4);
The negatively charged electric power (6) will decrease. It has been found that thermal sprayed ceramics with such an injection-blocking effect can be improved.

なお、上記実施例における溶身よセラミック層の材料は
、炭化シリコンあるいは酸イヒチクンに［定するもので
はなく、この炭化シリコンあるいは酸化チタンと、例え
ばアルミブー、酸イヒシ１ノコン等とを混合したもので
βつでもよい。又、ＰあるいはＮ型の伝導性を示す、例
えｔｆ酸イヒＤ’；！、　＠’ｉ等であってもよい。In addition, the material of the melted ceramic layer in the above embodiments is not limited to silicon carbide or acid oxide, but is a mixture of silicon carbide or titanium oxide and, for example, aluminum bu, acid hydroxide, etc. β is acceptable. Also, it shows P or N type conductivity, such as tf acid Ihi D';! , @'i, etc.

又、ａ−８ｉ層はＳｉ単独でなく　、ｆｌＪえばＧｅあ
るいはＳ　ｌ）等をＭ％　７ＪＤした混成漸としてもよ
く、又、酸化シリコン層あるいは窒素シリコン層を上記
α−５ｉ層の外表面あるいはそのｅ−３表田」、ＢＩｌ
方浴射溶射ミック層上に形成して複合層としてもよく、
いずれの場合も該ト°ラム表面におＶする電歪ヱ保持力
を改善することができる。又、ドラム相゛質にアルミニ
ウムに限らず、金属ドう１１であれば特に限定するもの
ではない。Furthermore, the a-8i layer is not made of Si alone, but may be a composite layer containing M% 7JD of Ge or Sl), and a silicon oxide layer or a silicon nitride layer may be formed on the outer surface of the α-5i layer or That e-3 Omoteda”, BIl
It may also be formed as a composite layer by forming it on a hot sprayed sprayed layer.
In either case, the electrostrictive retention force exerted on the surface of the tram can be improved. Further, the material of the drum material is not limited to aluminum, but is not particularly limited as long as it is a metal door 11.

以上のように、この発明によ第１．ば、導市、性を有す
る溶射セラミック層をα−５ｉ層の下塗！１１　Ｊａと
して用いたので、感光ドラムの機械強度を高くすること
ができ、さらに該セラミックＩ曽の伝導型をα−５ｉ　
層表面の帯電極性と同イ勿恰ミのものとすれは、該溶射
セラミック＃　７５’　％　Ｍ注ノ＼μＩＡ止′層とし
て働き、不感光ド；ムの帯％會ヒカを改善できるという
効果が得られる。As described above, the present invention has the following advantages. For example, the thermal sprayed ceramic layer with the properties is undercoated with the α-5i layer! Since it was used as 11 Ja, the mechanical strength of the photosensitive drum could be increased, and the conductivity type of the ceramic I was changed to α-5i.
The material, which has the same charge polarity as the surface of the layer, has the effect that the thermally sprayed ceramic #75'% M serves as a stop layer of μIA and can improve the band % ratio of the light-insensitive dome. is obtained.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は従来の電子写真用感光ドラムの村４Ｄ見断面図
、第２図はこの発明の一実−ｈ！１秒ｌによる昂７子写
真用感光ドラムの構成断面図、第３図は第２図１の部分
拡大図である。 （１）・・・金属ドラム、（２）・・・光導電体層（α
−５ｉ感光層）　、＋４１・・・溶射セラミック層。 なお、図中同一符号は同一、又は相当部分を示す。FIG. 1 is a 4D cross-sectional view of a conventional photosensitive drum for electrophotography, and FIG. 2 is an example of the present invention. FIG. 3 is a cross-sectional view of the structure of the photosensitive drum for photography taken at 1 second, and FIG. 3 is a partially enlarged view of FIG. 2. (1)...Metal drum, (2)...Photoconductor layer (α
-5i photosensitive layer), +41... thermal sprayed ceramic layer. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (2)

【特許請求の範囲】[Claims] （１）金属ドラムと、該金属ドラム上の全周に形成され
表面が研磨処理された導電性を有する溶射セラミック層
と、該溶射セラミック層上に形成された少なくともアモ
ルファスシリコンを含む光導電体層とを備えだことを特
徴とする電子写真用感光ドラム。(1) A metal drum, a conductive thermal sprayed ceramic layer formed around the entire circumference of the metal drum and whose surface is polished, and a photoconductor layer containing at least amorphous silicon formed on the thermal sprayed ceramic layer. A photosensitive drum for electrophotography, characterized by comprising: （２）上記溶射セラミック層が上記光導電体層表面のコ
ロナ帯電の帯電極性と同極性の伝導型のものであること
を特徴とする特許請求の範囲第１項記載の霜、子写真用
感光ドラム。(2) The thermal sprayed ceramic layer is of a conduction type having the same polarity as the corona charging polarity of the surface of the photoconductor layer, and the photosensitive material for frost and child photography as set forth in claim 1. drum.