JPS61107254A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve an image flow characteristic by subjecting the surface of an electrophotographic sensitive body to a silane treatment and/or alkylation treatment. CONSTITUTION:The surface layer of the electrophotographic sensitive body is preferably made of a material contg. silicon atoms or boron nitride and the surface of the electrophotographic sensitive body is preferably so treated as to con contain active hydrogen prior to the silane treatment and/or alkylation treatment. The silane treatment includes the reaction by a silane coupling agent and the reaction by a silylation agent and these reactions are effected in solns. by immersing the above-mentioned photosensitive body into solns. (toluene, TFH, etc.) contg. the silane coupling agent and silylation agent usually at an ordinary temp.-100 deg.C for 5 minutes-5 hours. The alkylation treatment (the treatment by the alkylation agent such as alkyl halide or Grignard reagent) is executed in place or in addition to the silane treatment. The silylation agent is executed in accordance with the conventional practice in which the photosensi tive body is brought into reaction (by immersing) in a soln. (toluene, benzene, TFH, etc.) contg. the alkylation agent at an ordinary temp.-100 deg.C for about 5 minutes-1 hour.

Description

Detailed Description of the Invention "Prior Art" Conventionally, amorphous silicon (Di under a- 131], which has the following advantages.

■ Hard (high printing durability) ■ High photosensitivity, allowing control of spectral sensitivity characteristics. For example, by introducing an a-81=Ge layer, long wavelength sensitivity (7 g Onm to t 00 nm) increases. , This makes it possible to use a photoreceptor for a laser printer that uses a semiconductor laser as a light source.

■ It is pollution-free.

■It is thermally stable.

``Problems to be Solved by the Optical BA''Although the A-8i photoreceptor has the above-mentioned advantages, it actually suffers from major problems such as image deletion and image blurring under high humidity conditions.

When compared to a-8θ, a-191 has a dielectric constant of 70~//
is 2 to 3 times larger, and the dark resistance ρd is IO1'~/θI
It is as small as SΩ・α. Therefore, in order to make the surface potential the same as a-8θ, change the corona current of the corona charger! −
It needs to be 70 times larger. Therefore, OA, O, - is generated by corona discharge.

The surface of the A-81 photoreceptor is significantly altered and deteriorated by N, + ions, NOX, and the like. This deterioration is particularly accelerated under high humidity. When a-5i photosensitive material with such deterioration is used for electrophotographic copying under high humidity, image deletion and image blurring may occur, and in severe cases, the image may not be produced.

The above-mentioned alteration and deterioration of the surface of the A-8 layer determines the practical life of the A-81 photoreceptor, and in many cases, the life span is no more than 30,000 copies per copy.

"Means for Solving the Problems" The present invention aims to solve the above problems.
By subjecting the surface of the electrophotographic photoreceptor to silane treatment and/or alkylation treatment, the image flow characteristics can be greatly improved. The electrophotographic photoreceptor surface layer of the present invention preferably contains silicon atoms, nitride, or boron. Further, the surface of the electrophotographic photoreceptor of the present invention is preferably treated to contain active hydrogen before silane treatment and/or alkylation treatment. Usually formed by vapor deposition (ion grating).

It is thought that the image-bleeding development occurs under high humidity and is caused by adsorption when the photoreceptor that has caused the image-bleeding is returned to a low-humidity environment.

Next, we analyzed the surfaces of the photoreceptors with and without image blur using XPS (X-ray photoelectron spectroscopy), and found that the surface of the photoreceptor with image blur KFi'□
It was found that there are many oxidized species such as , 'na+, No, and sto.

In addition, a-8iOx is used as a surface protective layer for a-8i bad sensitivity.
: When using one layer, a-sLOx: HM 7g
l: It has been found that as the gas flow rate ratio (NmO/8jlL) during formation increases, no image appears from the initial stage. The infrared absorption spectrum of this surface layer itself is shown in Figure 1, and as the N, O/Si & flow rate ratio increases, j e
It can be seen that the absorption of OH groups increases near 00 to J j'00cIIL-'.

Similarly, in the a-BLHx:H surface protective layer, N
For those with a large HI/5IH4 flow ratio (and where the ME group appears largely in the infrared spectrum, no images were obtained from the beginning).

Considering the above facts together, it can be concluded that the OH groups and 1+ present on the photosensitive surface of a-8i adsorb water molecules through NH groups. This adsorption is thought to be caused by physical adsorption (by hydrogen bonding) of the OH group attached to the S1 atom, which is assumed to have the form shown in the following formula, with water molecules, causing image blurring.

Therefore, in order to prevent image blurring, it is sufficient to treat the surface hydroxyl groups (or NH groups) so that water molecules do not form hydrogen bonds.

The first example of such a reaction is silane treatment.

The silane treatment of the present invention includes a reaction using a silane coupling agent and a reaction using a silylating agent.

Soak at ~ioo°C for ~1 hour.

The silica/coupling agent has the general formula R81K.

(R: Vinyl group; co(J, l-epoxycyclohexyl) ethyl group, J, J-epoxypropoxypropyl group% 3-methacrytetrayloxyglobil group, co-aminoethylaminoglobil group, etc. Ethoxy group, methacryloyl Alkyl group substituted with oxy group, amino group, etc.; x
:methoxy group, ethoxy group, silanol group, halogen]
The following are representative examples:

OHH<H8101m CHa =CH5i(OO*Ha)aO& =CH
S i (OOHz 0Fit 0OBs)a0H,
O He N(Ollt )t HE(OBa)s 5i(
OOHJnThese compounds have silanol groups (98
1-OH), it reacts with the following formula to provide a barrier effect against water.

The silylating agent converts active hydrogen into MeJi- or -Mθ, S
Typical silylating agents include the following.

(OHs) x F3LO1 (C, mountain)s siaJ (OH4)m EIiOmu (@frsic1 (OHs)
B101s OHH5i (OCRs) a 11^ Csxgc,; (OH, n, 8iBr (CH# n, EliF Among the above silylating agents, (O
Hm) *5iOJ,, (OEs)s 5iNIiSi(
OH,)s is preferred.

The above silylating agent is -OK %-000H, -0
0H.

-0H=OROR%-Nlllll, -0ONEa,
Reacts with active hydrogen in -8R group, etc.

The reaction between (OHa)s 8401 and the 10H group proceeds as shown below.

It is thought that it exists on the surface of an amorphous silicon photoreceptor: A stable s x - H (silanol group) to Ei-Si
By substituting to the o-si% form, the adsorption activity for water is eliminated, and by introducing a phenyl group in place of the methyl group, the surface hydrophobicity can be further improved.

In the present invention, instead of or in addition to the silane treatment, an alkylization treatment (treatment with an alkylating agent such as an alkyl halide or a Grignard reagent) is performed. Alkylation is carried out according to a conventional method in a solution containing an alkylating agent (toluene, benzene-T?He) at room temperature to lo.

React (immerse) for about 1 hour to 1 hour. 0 This reaction is based on the silanol groups present on the surface.
1. The purpose is to replace the -OH bond with a stable 81-c bond. Examples of reaction routes include those under Fim.

By alkylating the surface, the adsorption activity for water is completely eliminated and a hydrophobic surface is obtained.

The above-mentioned silane treatment and alkylation treatment can be performed at the time of manufacturing the photoreceptor or at the time of regenerating the photoreceptor. Also,
The surface side subjected to the above surface treatment is a-8i:H and/or a-8i:H:y
a-8i Gex: H and/or a-8
iGex:H:F'a-8iOx:H and/or
a-810x:H:Fa-8iC)x:H and/or a-8iOx:H:Fa-8iNx:H and/or a-8iNx:H:Fa-BNX:E and or a-BNX:H: F is the target.

Dangling bonds (S
i Tsuya! There are unstable elements such as weak bonds such as 31-H and 8l-8i bonds. Since these unstable elements tend to change into 5i-OH groups during corona discharge (especially under high humidity), it is preferable to actively remove these unstable elements after film formation. It is more preferable to carry out a silane treatment or an alkylation treatment after the conversion. For this purpose, corona irradiation, 0. Exposure, 0. Plasma treatment, acid (H
OJ, &SO4, HNO, aNol, etc.), but the present invention is not limited to the following examples as long as it does not exceed the gist thereof.

Example 1 Place the cleaned AJ substrate into the reaction container.

After baking in X air for 30 minutes at iooo℃ or higher, evacuate for 30 minutes with an oil diffusion pump to λX 10"-@T
orrO truth to degree. The oil rotary pump was switched again to flow the reaction gas, and a film was formed with the following layer configuration.

Blocking layer a-8iOx:H (-a, /11),
Substrate temperature 30℃ Photosensitive layer -/IJHa/Si&=0
．． 24.0.7Si, [4m, 01%&H4/Si&-
1Ovppm, substrate temperature 31660 minutes open film formation (da, 3μ
) Photosensitive layer-1 NHa/Si& = i, b%, but under the same conditions as l, except that O composition film was formed (ko, jμ) Surface layer: a-810 re=H CH4/51H4= bow Ht/SiL Also t ; o, /
Film formation for s i & = 445 minutes (~roof) \As above, a photoreceptor with a film thickness of approximately 7μ was obtained, which was placed in a copying machine and subjected to 13,000 corona discharge-exposure-discharge cycle treatment. After performing this, when the image was photographed in an atmosphere of JO°C-g ORH, image blurring occurred.

This image blurring sample was immersed in trimethylchlorosilane for 70 minutes, washed with methanol, washed with water, and then vacuum dried. Place this in the copy machine again and set it at 30°C.
When photographed at -gO%RH, an extremely clear image was obtained.

Example Coblocking The photosensitive layer was formed in the same manner as in Example 1, and then a-8iOx:H(N
, O/EIi&= ,? ) to layer 1! Deposit on r00.

When this sample was photographed, no image appeared from the beginning under the condition of 0% RH.

This sample was immersed in a j% toluene solution of trimethylchlorosilane for 73 minutes, washed with methanol and water, and dried in vacuum. Thereafter, when the image was photographed at 30° C. and tO%RH, a clear and high-resolution image was obtained.

This sample showed no change in image quality even when it was subsequently subjected to corona discharge treatment corresponding to io million copies.

[Brief explanation of drawings]

Figure 1 shows a-8i as a surface protective layer for a-8i bad sensitivity.
FIG. 3 is an infrared absorption spectrum diagram of an Ox:H layer when the gas flow rate ratio (N, O/Si & ) when forming the layer is changed. Applicant: Mitsubishi Chemical Industries, Ltd. Agent: Patent Attorney: Yo Hase: 21. ! 9.
7) Written on the voluntary basis of the procedure) November 2, 1985

Claims (2)

[Claims] (1) An amorphous silicon electrophotographic photoreceptor whose surface is silane-treated and/or alkylated. (2) The amorphous silicon electrophotographic photoreceptor according to claim 1, wherein the surface has been previously treated to contain active hydrogen.