JPS63241549A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a photosensitive body high in sensitivity and good in characteristics by incorporating polysilane containing Ge. CONSTITUTION:The organic polysilane to be used as one component of the photosensitive body contains Si and Ge for the main chain of the polymer, and at least one hydrocarbon residue per one silicon atom, and it is obtained by dehalogenation polycondensing, preferably, dihalogenosilane and/or dihalogenodisilane having at least one hydrocarbon residue per one Si atom in the presence of Ge halide, thus permitting the obtained electrophotographic sensitive body to be enhanced in characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic photoreceptor. More specifically, the present invention relates to an electrophotographic photoreceptor containing a specific polysilane.

[Conventional technology]

Electrophotographic photoreceptors are made of organic compounds such as combinations of various pigments such as phthalocyanine pigments, diazo pigments, and perylene pigments with polyvinylcarbazole, oxadiazole, hydrazone, pyranophosphorus, etc.
Compared to electrophotographic photoreceptors made of inorganic photoconductive compounds such as cadmium sulfide, they have advantages such as non-pollution and high productivity, and various combinations of high sensitivity and excellent durability have been proposed.

[Problem that the invention seeks to solve]

The above-mentioned various pigments or organic compounds cannot produce good films by themselves, and it is necessary to use various binders in combination. As a result, there are numerous problems such as deterioration of photoconductive properties and deterioration of durability.On the other hand, there is also a known method that uses a polymer such as polyvinylcarbazole as a photoconductive or electron or hole conductor without using a binder. However, there were problems such as poor film forming properties.

[Means for Solving the Problems] The present inventors have diligently studied methods for solving the above problems, and have found that by using a specific compound, an electrophotographic photoreceptor with high sensitivity and good characteristics can be obtained. They found this and completed the present invention.

That is, the present invention is an electrophotographic photoreceptor characterized by containing polysilane containing germanium.

The electrophotographic photoreceptor of the present invention may be either a multi-layer type having at least two functionally separated layers, a charge generation layer and a charge transfer layer, or a single-layer type in which functions are not separated.
The use of the organic polysilane of the present invention in any layer is effective in improving the performance of the electrophotographic photoreceptor.

What is important in the present invention is the use of organic polysilane containing germanium as one component of the photoreceptor.

In the present invention, the organic polysilane used is a polysilane containing silicon and germanium in the main chain of the polymer and having at least one hydrocarbon residue per silicon atom, preferably a dihalogen polysilane having at least one hydrocarbon residue. It is obtained by dehalogenation polycondensation of silane and/or dihalogenodisilane in the presence of germanium halide. Specifically, dimethyldichlorosilane,
Dichlorosilane such as methylphenyldichlorosilane, diphenyldichlorosilane, diethyldichlorosilane, ethylphenyldichlorosilane, dipropyldichlorosilane, propylphenyldichlorosilane, tetramethyldichlorodisilane, trimethylphenyldichlorodisilane, dimethyl Dichlorodisilanes such as diphenyldichlorodisilane, dimethyldiethyldichlorodisilane, trimethylethyldichlorodisilane and their fluoride derivatives, and germanium halides, preferably germanium dihalides, specifically dimethyldichlorogermanium, diethyldichloro. Dehalogenation polycondensation of germanium, dipropyldichlorogermanium, dibutyldichlorogermanium, diethyldichlorogermanium, diphenyldichlorogermanium, nuclear substituted products thereof, and compounds in which chlorine of these compounds has been replaced with fluorine, bromine, or iodine, and mixtures thereof Here is an example of what you can get by doing this. Although there are no particular limitations on the method for producing organic polysilane by dehalogenation polycondensation, a preferred example is a method of heating and contacting the germanium halide and dihalogenosilane and/or dihalogenodisilane and an alkali metal [for example, R,C0West,Com
prehensiveOrganicChe++1st
ry, Vol, 2. Chapter 9.4. P365～
3B? (1982), edited by G. Wil.
kjnson et al, +Pergamon Pr
ess.

New York,, Po1ya+er Pre
prints, 1986.27 (2) 261+Mi
ng-ta S, Hsu et al, 3.

As the organic polysilane, an asymmetric one such as non-grade polysilastyrene which is soluble in an organic solvent is preferably used, and the germanium content is usually 0.0001 to 0.10 mol based on silicon. Those containing a certain number of gesimanium units are preferably used.

In the present invention, the polysilane is used as a dispersion medium for pigments in the charge generation layer, and as a dispersion medium for various unsaturated group-containing organic compounds in the charge transfer layer. Used as a dispersion medium for group-containing organic compounds.

In the present invention, various materials can be used as the charge generating layer, and there are no particular limitations, and many pigments known for electrophotography can be used. quinone pigments such as algol yellow, pyrenequinone, indanthrene brilliant, and violet RRP, quinocyanine pigments, indigo pigments such as indigo and thioindigo, bisbenzimidazole pigments such as Indofast Orange, and phthalocyanines such as copper phthalocyanine. and quinacridone pigments such as quinacridone.

In the present invention, the above-mentioned pigment is simply dispersed in the above-mentioned polysilane, and if necessary, 2,4.7-trinitrofluorenone, dicyanobenzene, tetracyanoethylene, aromatic dicarboxylic acid ester, triphenylamine, triphenylamine, etc. An electrophotographic photoreceptor can be obtained by coating a conductive support layer with phenylmethane or the like.

In the present invention, it is also possible to form an electrophotographic photoreceptor by further forming a charge transfer layer on the layer in which the pigment is dispersed, but in the case of a single layer type, the layer in which the pigment is dispersed ranges from several microns to
With a thickness of several tens of microns, the ratio of pigment to total solids is 0.0
It is about 5 to 0.5. 0.005 when using multilayer type
It has a thickness of ~ several microns, and the proportion of pigment is 0.1~0.
It is about 9. In addition, in a multi-layer type, the charge generation layer has a relatively high pigment concentration and other binders, such as polyester,
It is also possible to use polyvinyl butyral, polycarbonate, polystyrene, polyvinyl chloride, methyl cellulose, polyacrylic, or the like as a charge transfer layer by dispersing the organic compounds shown below in organic polysilane. Here, the organic compounds used in the charge transfer layer include polycyclic aromatic compounds such as anthracene, pyrene, and phenanthrene;
Examples include nitrogen-containing cyclic compounds such as indole, carbazole, oxazole, isoxazole, thiazole, imidazole, pyrazole, oxadiazole, pyrazoline, and thiazole.

In the present invention, the injection of free charges from the conductive support layer to the charge generation layer is prevented between the charge generation layer and the conductive support layer provided thereunder, and the adhesion between the charge generation layer and the conductive support layer is improved. A layer made of aluminum oxide, indium oxide, tin oxide, polypropylene, acrylic resin, methacrylic resin, polyvinyl chloride resin, epoxy resin, polyester, acrylic resin, polyurethane, polyimide, etc. can also be provided to improve the performance.

〔Example〕

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

Example 1 β-type steel phthalocyanine (manufactured by Toyo Ink Mfg., Llon)
ol Blue NCB Tonor) 991 parts of toluene was added to 1 part by weight, and ultrasonic dispersion was performed for 24 hours.
Byron 200) lO% tetrahydrofuran solution 50
A coating solution prepared by mixing parts by weight and the above dispersion was applied onto a 100 μm thick aluminum plate using a film applicator and dried to form a charge generation layer with a thickness of 0.5 μm.

This 1 was placed on top of the loading layer, and dimethyldichlorosilane, methylphenyldichlorosilane, and dichlorosheetbutylgermanium were polycondensed with sodium metal in toluene in a ratio of 1:1:o, os, resulting in an average molecular weight of 90,000. A solution prepared by dissolving 1 part by weight of polysilane containing germanium in a molar ratio of 0.03 to silicon in 10 parts by weight of toluene was coated and dried to form a charge transfer layer with a thickness of 8 μm.

The characteristics of the laminated electrophotographic photoreceptor produced in this way were evaluated using an electrostatic paper analyzer EPA-
8100 (manufactured by Kawaguchi Denki ■). First, -
After performing a 6 kV corona discharge for 2 seconds and measuring the initial surface potential, it was left in a dark place for 2 seconds, and then passed through a color glass filter IR-80 (manufactured by Hoya Glass ■) at an illuminance of 20
The half-life exposure was measured by applying lux light. Display the results -
1, set the initial voltage to ■0, and set the half-reduced exposure amount to [++zz(lux
-sec).

Examples 2 to 3 In addition to adding 2,4.7-)linitroffluorenone (l/20 wt ratio to polysilane, Example 2) and todicyanobenzene (1/20 wt ratio to polysilane, Example 3) to polysilane. A photoreceptor was manufactured in the same manner as in Example 1, and the characteristics of the photoreceptor were measured in the same manner as in Example 1. The results are shown in Table-1.

Example 4.5 The polysilica obtained in Example 1 was prepared by adding 99 parts by weight of toluene to 1 part by weight of τ-type phthalocyanine "Liophon" (trademark, manufactured by Toyo Ink Mfg. ■) and performing ultrasonic dispersion for 24 hours. A coating solution prepared by mixing 1 part by weight of styrene in 9 parts by weight of tetrahydrofuran and 10 parts by weight of the above dispersion was applied onto a 100μ thick aluminum plate using a film applicator, and then heated at 80°C in the dark. After drying for 1 hour, a photosensitive layer having a thickness of 7 μm was formed.

The characteristics of the electrophotographic photoreceptor thus prepared were measured using an electrostatic vapor analyzer "EPA-81".
00' (manufactured by Kawaguchi Denki ■).

In Example 4, first, -6 kV corona discharge was applied to 2
After measuring the initial surface potential for 2 seconds, it was left in a dark place for 2 seconds, and then exposed to light with an illuminance of 5.0 Iux through a color glass filter IR-80 (manufactured by Hoya Glass) and heated at half f.
The li exposure amount was measured.

In Example 5, the corona discharge was set to +6 kV.

The results are shown in Table-2.

Comparative Example 1.2 Polyester resin (Vylon 200) was used instead of polysilane
When the same procedure as in Examples 1 and 5 was carried out except for using Toyobo (manufactured by Toyobo ■), the surface potential was not halved (Comparative Example 1), and the halved exposure amount was 2.81 ux-sec (Comparative Example 2).
, all had poor sensitivity.

〔Effect of the invention〕

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

Claims (1)

[Scope of Claims] 1. An electrophotographic photoreceptor characterized by containing polysilane containing germanium. 2. Claim 1, wherein the germanium-containing polysilane is obtained by dehalogenation polycondensation of a dihalogenosilane having at least one hydrocarbon group and/or a dihalogenodisilane and a germanium halide. the method of.