JPS59180562A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To facilitate manufacture and to enhance efficiency of carrier injection from an electrostatic charge generating layer to a charge transfer layer by forming the charge transfer layer made of a charge transfer substance consisting of a diazo component and a coupling component, and the charge generating layer made of a charge generating substance composed of an azo dye formed by treating one side of the transfer layer through coupling. CONSTITUTION:A charge transfer layer is composed of a charge transfer substance made of a diazo component and a coupling component, and a charge generating layer is composed of a charge generating substance made of an azo dye formed by treating one side of the charge transfer layer through coupling. The diazo component and the coupling component act as a positive hole transferring substance, and they are usable so long as they absorb the visible light little, and they are small in ionization energy. A mixing ratio of both components is not limited. They are usually dispersed into an org. binder in an amt. of 10-90wt%. Such a charge transfer layer usually has 2-50mum thickness. The coupling treatment is carried out in a neutral or weak acid condition when the coupling component is an aromatic amine, and in a weak alkaline condition when it is one of phenols, and executed, e.g., by heating in the case of a neutral condition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electrophotographic photoreceptor, and more particularly, to a multilayer electron photoreceptor in the Carlson electrophotography system.

[Technical Background of the Invention] In general, an electrophotographic photoreceptor based on the Carlson method is required to have a high electric resistance value in a dark state and excellent charging properties. η) and - on the conductive support
・Even if photoreceptors in the early stages of development, which were made by stacking photoconductors in layers, had high sensitivity in the visible region, their electrical resistance in the dark state was often low (K), so electrophotography using the Carlson method was It was difficult to apply it to

For this reason, photoreceptors are now being used in which the chargeability of the photoreceptor is improved by separating the charge generation layer and the charge transport layer, thereby improving the sensitivity. This photoreceptor has the advantage that since the charge transport layer does not need to generate charges, a material having excellent charge retention ability and charge transport can be selected as the charge transport material for the layer. In a photoreceptor having such a laminated structure, excitons (excitation-r) generated in the charge generation layer by light irradiation dissociate within the charge generation layer or near the boundary between the charge generation layer and the charge transport layer to release carriers. It is thought that the carriers (holes or electrons) are generated and transported into the charge transport layer to neutralize the charges on the surface of the photoreceptor, thereby forming an electrostatic latent image.

In J2 laminated photoreceptors, the charge generation layer is usually thinner and has weaker mechanical strength than the charge transport layer, so the charge transport layer is two layers and the charge generation layer is one layer. . In addition, as the charge transport substance, a hole transport substance such as polyvinylcal 7-sol, oxadianol, or a derivative thereof, which is an organic semiconductor transparent to visible light, 2,4.7
- Electron transport materials such as trinitro-8-fluorenone are known and are dissolved and dispersed in an organic binder to form a charge transport layer.

[Problems with Background Art] The first new problem that has arisen since the photoreceptor is of a laminated type is that it is technically difficult to create a laminated type. That is, it is technically difficult to coat a charge generation layer on a conductive support and then coat a charge transport layer thereon, and even if it is successful on a laboratory scale, it is difficult to carry out on an industrial scale. Met.

The second problem is the problem of charge injection from the charge generation layer to the charge transport layer. That is, even if the charge generation layer has good carrier generation efficiency and the charge transport layer has good carrier transport efficiency, if the carrier injection efficiency in both layers is poor, a photoreceptor with excellent characteristics cannot be obtained. That's what it means. In general, carrier injection efficiency is considered to depend on the energy level, trap level, degree of oxidation, etc. of the charge-generating substance and the charge-transporting substance.
In order to improve the efficiency, it is most important to improve the affinity and adhesion between the charge generation layer and the charge transport layer. However, this was not always easy technically. Therefore, most of the many charge transport materials that have been developed so far are hole transport materials, but photoreceptors that can efficiently inject holes generated in the charge generation layer into the charge transport layer. development was desired.

[Object of the Invention] An object of the present invention is to provide an electrophotographic photoreceptor that is easy to manufacture and has excellent carrier injection efficiency from a charge generation layer to a charge transport layer.

[Summary of the Invention] The present invention provides an electrophotographic photoreceptor comprising a conductive support, a charge generation layer, and a charge transport layer, in which the charge transport layer is comprised of a charge transport substance comprising a diazo component and a campling component. The charge generating layer is characterized in that the charge generating layer is composed of a charge generating material made of an azo dye formed by campling treatment on one side of the charge transport layer.

The electrophotographic photoreceptor of the present invention may have a structure in which a conductive support, a charge generation layer, and a charge transport layer are laminated in this order, or may have a structure in which the charge generation layer is the uppermost layer.

In the present invention, since the conductive support is not substantially related to the function of a photoreceptor, its material is not particularly limited, but it is usually a resin film coated with a conductive substance. things are used. As the conductive substance, for example, metals such as AI, In, Au, Cu, Ni, Sn, Zn, and Heg are used. The thickness of the support is 50~
It is in the range of 500 μm.

The charge transport layer in the present invention is formed by dispersing a diazi component, a force, -/ring component, and, if necessary, additives such as a stabilizer in an organic binder. The diazi component and the coupling component function as hole transport substances. As the diazid component and the coupling component, any compound can be used as long as it hardly absorbs visible light and has a small ionization energy. As these components, azo dyes that are commercially available in an uncamped state can be used as they are.

As the diazi component, for example, fast pol);'-G
P base, first orange GC base.

First Scalen 1-GG Base, First Carnet GBC Pace, First Red B Pace, First Orange GR Base, First Orange R Pace, First Rent G Heath.

First Trend 3GL Base, First Red RC
base, First Blue BB base, etc.

Examples of camping components include naphthol AS, naphthol AS-BO, naphthol AS-G, naphthol AS-3W, naphthol^5-TR, and naphthol A.
S-L4G, Naphthol AS-E, Naphthol AS-
RL, naphthol AS-ITR, naphthol AS-P
H, naphthol AS-LB, naphthol AS-[]B,
Examples include naphthol AS-BS, naphthol AS-D, naphthol AS-BG, naphthol As-KB, naphthol AS-LC, and the like.

In addition, various commercially available azo dyeing dyes 1, which contain diazine ingredients and campling ingredients, are available at Kawazaimura.
Specific examples include Rapidogen Yellow G, Rapidogen Yellow CG, Rapidogen Orange G. rapidogenscaren hlR, rapidogenlent'R, rapidogenle, deG, trapitogenscarn
/, 1・IL, Rapidogen dyes such as Rapitogen Bordeaux RN, Rapitogen Pol F'-IB, Rapitogen Iolent B, Rapidogen Blue B, Rapidogen Blue-IB
, Lapitasil dyeing material such as Lapita tool blank B 1
Nila Pinto First Yellow GO)l, La Pinto First Yellow GH, La Pinto First Orange G
H, Rabbit Fast Trend B, Rapid Fast Scalent IL) I, Rapid Fast γ-Star Trend RH, Rapid Fast Red FG) I, Rabbit Fast Bordeaux IB, Rapid Fast Red G2
Examples include rapid fast dyes such as H 2 and the like.

On the other hand, as the organic binder, any substance can be used as long as it is a substance conventionally used for forming a charge transport layer. Specific examples include polystyrene and polycarbonate.

Examples include polyethylene, hinyl acetate-1n vinyl copolymer, acrylic polymer, methacrylic polymer, and the like.

The addition ratio of the diazo component to the compulsory component is not particularly limited, but is usually 5.1 to 1:5, preferably 1°1.
is within the range of The diazo component and the coupling component are generally dispersed in the organic binder in a range of 10 to 90% by weight, preferably 40 to 6% by weight. Such charge transport layers typically have a thickness of 2 to 50 gm.

The charge generation layer in the present invention is formed by subjecting one side of the charge transport layer described above to a compulsion treatment. Here, the force and pulling treatment means any treatment required to compile the diazo component, which is a charge transport substance, and the coupling component. Normally, when aromatic amines are used as a sampling component, it is carried out in neutral or weakly alkaline conditions, and when phenols are used as a strength/sampling component, it is carried out in weakly alkaline conditions. In addition, when carrying out in neutrality, it heats, for example. From a political point of view, there are known methods depending on the type of the diazine component and the coupling component, and the complation treatment is carried out according to this method. The azo dye produced functions as a charge generating material, providing pores to the charge transport layer and neutralizing the load on the layer. As an example of the treatment method, in the case of Lapitogen dye, Lapitanur Dye $1 and Lapin IS γ-S I-Dye 1, when treated in an acidic environment, campling occurs and color develops. As such a liquor, it is possible to use either an inorganic acid or an organic acid, but it is preferable to use a weak acid such as phosphorus. Usually, from one surface of the charge transport layer, Ol~
Compounding is performed to a depth of 0.5 μm.

In the photoreceptor of the present invention, for example, an organic binder in which a predetermined amount of a diazine component, a campling component, and, if necessary, other additives are dispersed, is coated on the entire curved surface side of the conductive support. It can be obtained by forming a charge transport layer and then subjecting the surface of the charge transport layer to a coupling treatment to form a charge generation layer. In addition, in this manufacturing method, a photoreceptor having a charge generation layer as the uppermost layer is obtained, but this layer is used as a conductive support]-. If you want to directly form the layer, for example, create a layer of an organic binder in which diazide and camplink components are dispersed, perform a coupling treatment on one side of the layer, and then apply a paste or the like to the treated surface. The method of adhering to the conductive support through the adhesive is adopted.

[Effect of the Invention 1] In the photoreceptor of the present invention, a charge generation layer can be easily formed simply by coupling the surface of the charge transport layer;
Pear-shaped production is possible. Furthermore, since the charge generation layer and the charge transport layer are integrally formed, carriers 11 are transferred from the charge generation layer to the charge transport layer with good efficiency and extremely excellent characteristics.

[Embodiment 1 of the Invention A polyethylene terephthalate resin film on which aluminum is vapor-deposited is used as a conductive support, and on the aluminum side thereof, Ravidokenlend R (rffi product name, Naphthol MS-OL, First Trend RC Base, Sarcosine) '80ffii% Polycarbonate 1 with dispersed
The resin liquid was applied and dried to form a charge transport layer with a thickness of about 20 gm. Next, the surface of the layer was coated with 2 mol/R
A charge generation layer having a thickness of about 0.5 gm was formed by treatment with an aqueous solution of phosphoric acid.

The attenuation of the surface potential when the photoreceptor was irradiated with light was measured using an electrostatic charging tester (manufactured by Kawaguchi Electric Seisakusho, MOD).
ERU 5P-428), results indicated by A in the figure were obtained.

Further, a photoreceptor was produced in the same manner as in [-] using the azo dye shown below.

B First Trend KB Hess, Naphthol AS-D
, Sarcosine C first/Heolet B base, Naphthol AS
, Sarcosine D) γ-St Blue RR Base, Naph I-L AS,
N-Methyltaurine For each photoreceptor obtained, the attenuation of the surface potential was 71%.
111, the results shown as B, C, and D in the figure were obtained.

For comparison, PET coated with aluminum
Substrate 1. , Fastren 1'Rc Hess, Naft-
AS-OL, a charge generation layer is formed by binding an azo dye produced by treating sarcosine with phosphoric acid with a polyester resin, and then fast rent R is applied to the "-" of the layer.
A photoreceptor was manufactured in which a charge transport layer was formed by bonding a C base with a polyester resin.

The attenuation of the surface type (<7) of the photoreceptor was measured in the same manner as described in L. The obtained results are indicated by E in the figure.

[Brief explanation of the drawing]

The figure is a diagram showing the relationship between the attenuation of the surface potential and the light irradiation time when the surface of the photoreceptor is irradiated with light.

Claims (1)

[Scope of Claims] A T-photographic photoreceptor comprising 11 conductive supports, a charge generation layer, and a 1L transport layer, wherein the charge transport layer is made of a charge transport substance comprising a diazine component and a coupling component. 1. An electrophotographic photosensitive member characterized in that the charge generation layer is composed of a "load generation material" made of an azo dye formed by a compulsion treatment on one side of the charge transport layer.