JPS63127251A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To render the electrophotographic sensitive body incinerable after its use, to improve sensitivity, and to maintain residual potential not high by forming a layer containing a pigment dispersed into an organosilane on a conductive substrate made of a phenol resin. CONSTITUTION:The conductive substrate to be used is made of the phenol resin containing carbon dispersed in the resin, and the layer containing the pigment dispersed into the organosilane obtained by dehalogenating and polycondensing dihalogenosilane having at least one hydrocarbon residue and/or dihalogenodisilane is formed on the substrate. This organopolysilane contains and when needed, 2,4,7-trinitro-9-fluorenone dicyanobenzene, tetracyanoethylene, aromatic dicarboxylate, triphenylamine, or the like is combination with the dispersed pigment, and the phenol resin substrate containing the dispersed carbon is coated with this pigment dispersed polysilane, thus permitting the intended electrophotographic sensitive body to be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic photoreceptor. Specifically, the present invention relates to an electrophotographic photoreceptor comprising a specific conductive support layer and a specific photoreceptor layer.

[Conventional technology]

Electrophotographic photoreceptors using organic photoconductors such as polyvinylcarbazole and oxadiazole are less polluting than inorganic photoconductors such as selenium and cadmium sulfide.
In addition, it has the advantage of high productivity, and various improvements have been made, and products with extremely high sensitivity are being proposed.

[Problems to be Solved by the Invention] The electrophotographic photoreceptor using the above-mentioned high-grade organic photoconductor has the following problems:
Although it has the advantage of being able to be incinerated after use, it usually uses a conductive support layer made of metal such as aluminum, and has the problem that it cannot be incinerated. It is also known to use a resin in which a conductive substance such as carbon is dispersed as a conductive support layer, but in this case, a functionally separated multilayer structure consisting of a highly sensitive charge generation layer and a charge transport layer is used. However, there were problems in that the sensitivity was poor and the residual potential was also large.

[Means for solving problems]

The present inventors have diligently searched for an excellent electrophotographic photoreceptor that solves the above problems, and have completed the present invention.

That is, the present invention is an electrophotographic photoreceptor in which a layer in which pigment is dispersed in organic polysilane is provided on a phenol resin layer in which carbon is dispersed.

There are no particular restrictions on the production method of the carbon-dispersed phenolic resin used as the conductive support layer in the present invention (although products made by various known methods can be used, at least It is preferable that the electrical resistance is 10'Ω or less, particularly 10'Ω or less.The phenolic resin in which carbon is dispersed is, for example, a phenolic resin prepolymer such as resol or novolac, with carbon added in an amount of 5wt% or more, preferably 10wt% of the total. % or more, along with a reinforcing agent or an extender if necessary, followed by molding and heat curing.

In the present invention, a layer in which pigments are dispersed in organic polysilane is provided on the conductive support layer of the phenolic resin. Here, as the organic polysilane, a polysilane having at least one hydrocarbon residue per silicon atom is used, preferably a dihalogenosilane and/or a dihalogenodisilane having at least one hydrocarbon group is subjected to dehalogen polycondensation. What is available is used. The dihalogenosilane and dihalogenodisilane used here include dimethyldichlorosilane, methylphenyldichlorosilane, diphenyldichlorosilane, diethyldichlorosilane, ethylphenyldichlorosilane, dipropyldichlorosilane, and propylphenyldichlorosilane. Dichlorosilane such as silane, tetramethyldichlorodisilane, trimethylphenyldichlorodisilane, dimethyldiphenyldichlorodisilane, dimethyldiethyldichlorodisilane,
Specific examples include dichlorodisilanes such as trimethylethyldichlorodisilane, and fluorides thereof in addition to the above-mentioned chlorides.

There are no particular limitations on the method for producing polysilane by dehalogenation polycondensation from dihalogenosilane and/or dihalogenodisilane, but a method of heating and contacting the dihalogenosilane and/or dihalogenodisilane with an alkali metal is preferred. For example, R, C, West,
Comprehensive Organic Chem
istry, Vol. 2. Chapter 94. P
365-387 (1982).

edited by GJilkinson et a.
l,, Pergamon Press+NeIIYor
k).

Pigments used in the present invention include, for example, azo pigments such as Sudan Red, Diane Blue, and Jenas Green B; quinone pigments such as Algol Yellow, Pyrenequinone, Indanthrene Brilliant, and Violet RRP; quinocyanine pigments; Examples include indigo pigments such as indigo and thioindigo, bishenthiimidazole pigments such as Indofast Orange, phthalocyanine pigments such as copper phthalonanine, and quinacridone pigments such as quinacridone, with phthalocyanine pigments and azo pigments being particularly preferred.

In the present invention, the pigment is dispersed in the organic polysilane, and if necessary, 2,4.7-1-dinitro-9
- Making an electrophotographic photoreceptor by using fluorenone, dicyanobenzene, tetracyanoethylene, ester of aromatic dicarboxylic acid, triphenylamine, etc. in combination and coating it on the phenolic resin layer in which the above-mentioned carbon is dispersed. I can do it.

Here, the ratio of pigment to organic polysilane is 0.
01-3 weight ratio, preferably 0.05-0.2 weight ratio.

〔Example〕

The present invention will be further explained below with reference to Examples.

Example 1 τ-type metal-free phthalocyanine (manufactured by Toyo Ink ■, Liop
(1 part by weight) was dispersed in 100 parts by weight of toluene using ultrasonic waves for a long time.

1 part by weight of the above dispersion and polysilastyrene (synthesized from dimethyldichlorosilane and diphenylcyclosilane)
The mixture was thoroughly mixed with 1 part by weight of a 10 wt% THF solution, and coated using a dip coater method on a plate of phenolic resin (surface resistance 1.2 x 10"Ω) in which 20 wt% of carbon was dispersed and 1 m thick. It was dried at C for 1 hour.

The performance of the obtained single-layer photoreceptor with a thickness of 15 μm was measured using an electric paper analyzer (manufactured by Kawaguchi Denki ■), which was corona charged to +6.0 V, and then left in a dark place for 2 seconds. Furthermore, the sample was examined by irradiating it with light at an illuminance of 51 ux through a color glass filter IR-80 (manufactured by Hoya Glass) for 10 seconds.

The results are shown in the table below.

Comparative Example 1 1 part by weight of the metal-free phthalocyanine dispersion used in Example 1 and 1 part by weight of a 5 wt% THF solution of a saturated polyester resin (Toyobo Co., Ltd., Byron 200) were thoroughly mixed. After applying it by dip coater method on the same phenolic resin plate as used, it was coated with 0.5
The mixture was dried for an hour to form a charge generation layer with a thickness of 0.5 pm. Furthermore, hydrazone compound 2 represented by the following structural formula
Parts by Weight 2 parts by weight of a saturated polyester resin were dissolved in a mixed solvent of 3 parts by weight of toluene and 7 parts by weight of THF, coated in the same manner, and dried at 100°C for 1 hour to give a thickness of 2 parts by weight.
The charge transfer layer was 0 μm thick.

The characteristics of this two-layer photoreceptor were investigated in the same manner as in Example 1, except that corona charging to -6, OKV was performed.

The results are shown in the table below.

The dark current is large and the sensitivity is also poor.

Reference Example 1 A photoreceptor was prepared in the same manner as in Example 1 and Comparative Example 1, except that an aluminum plate was used instead of the phenolic resin in which carbon was dispersed, and its characteristics were examined under the same conditions.

The results are shown in the table below.

When the substrate is an aluminum plate, the two-layer type shows rather better performance.

Comparative Example 2 A photoreceptor was prepared in exactly the same manner as in Example 1, except that saturated polyester resin was used instead of polysilastyrene, and its characteristics were investigated.

The results are shown in the table below.

The residual potential is large and the sensitivity is also poor.

Example 2 The same procedure as in Example 1 was carried out except that a solution in which 1 part by weight of τ-type metal-free phthalocyanine and 0.1 part by weight of metadicyanobenzene were dispersed in 100 parts by weight of toluene was used.

〔Effect of the invention〕

The electrophotographic photoreceptor of the present invention can be used not only in electrophotographic copying machines, but also in a wide range of electrophotographic applications such as laser printers, CRT printers, and electrophotographic plate making systems, and has industrial value. be.

Claims (1)

[Claims] 1. An electrophotographic photoreceptor comprising a layer of pigment dispersed in organic polysilane on a phenolic resin layer in which carbon is dispersed. 2. The method according to claim 1, wherein the organic polysilane is obtained by dehalogen condensation of a dihalogenosilane and/or dihalogenodisilane having at least one hydrocarbon residue.