JPH0325449A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain the photosensitive body having excellent photosensitive characteristics and further a sufficient photoconductive sensitivity even to a semiconductor laser by incorporating a specific naphthalocyanine compd. into a photosensitive layer. CONSTITUTION:The org. photoconductive material of the electrophotographic sensitive body is the naphthalocyanine compd. expressed by formula I. In the formula I, a substituent X is a group expressed by different or the same -Z<1>-R<1>-Z<2>; Z<1> denotes oxygen or sulfur; R<1> denotes 1 to 18C or branched alkylene group, etc. Z<2> denotes the org. group selected from halogen, 1 to 8C alkyl group, etc.; R<2> to R<5> denotes the org. group selected from 1 to 18C straight chain or branched alkyl, etc. M denotes hydrogen, the group, etc., selected from metals, etc.; n denotes the number of the substituent X and is 0 to 2 integer which may be the same or different. The photosensitive body which has the excellent photosensitive characteristics and the sufficient photoconductive sensitivity even to the semiconductor laser is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electrophotographic photoreceptor using an organic photoconductive substance.

(Prior art) Conventionally, electrophotographic photoreceptors have been made of inorganic photoconductive substances such as selenium, cadmium sulfide, and zinc oxide, and organic polymer photoconductive substances such as polyvinylcarbazole, polyvinylan), and helix. chemical substances, carbazoles, anthracenes, fluorenones, hydrazones, birazolines,
Products using organic low-molecular photoconductive substances such as oxadiazoles, cyanine dyes, and quinone dyes have been developed and put into practical use.

Among these, many methods using organic photoconductive substances have been proposed due to their advantages such as low toxicity, wide selection of wavelength ranges, and low cost.

On the other hand, in recent years, laser printers have been proposed as printers for digital copying machines, 7mm facsimile machines, word processors, etc., and electrophotographic photoreceptors are also used here.

Further, in order to improve the photosensitive characteristics of the photoreceptor, a laminated type electrophotographic photoreceptor in which a charge generation layer and a charge transport layer are functionally separated is also well known.

(Problems to be Solved by the Invention) As mentioned above, when using an organic photoconductive material for a photoreceptor, it has advantages such as safety, cost, and ease of selection. It is still difficult to say that it is sufficient in terms of characteristics. In addition, there are almost no conventional organic photoconductive substances that have effective photoconductive sensitivity in the oscillation wavelength range of semiconductor lasers and are also excellent in stability.

(Means for Solving the Problems) In order to solve the above problems, the present inventors investigated and discovered an organic photoconductive material that has excellent photosensitivity and stability as an electrophotographic photoreceptor. It was applied to electrophotographic photoreceptors. That is, the present invention... In an electrophotographic photoreceptor comprising a layer containing at least an organic photoconductive substance on a conductive support, the organic photoconductive substance is a naphthalocyanine compound represented by the following general formula [1]. This is a characteristic electrophotographic photoreceptor.

(In the above formula, the substituent X is different or the same -Z'
-R'-22, Z' represents oxygen or sulfur, and R' is linear or branched alkylene having 1 to 18 carbon atoms, polyoxyalkylene, or polyoxyalkylene having 6 to 14 carbon atoms. It represents a divalent organic group selected from arylene or cycloalkylene having 4 or more carbon atoms, and Z 2 is halogen, alkyl having 1 to 8 carbon atoms, hydrogen, -OR"
．． -SR3, -NR' R5 is an organic group selected from R5, and R2 to R5 are linear or branched alkyl having 1 to 18 carbon atoms, allyl, alkenyl, polyoxyalkyl having 6 to 14 carbon atoms, and Represents an organic group selected from 4 or more cycloalkyls. M is hydrogen, metal, metal oxide,
Indicates a group selected from metal halides and metal hydroxides, where n is ij! ! ．． It represents the number of IJX and is an integer from O to 2, and may be the same or different. ) The structure of the electrophotographic photoreceptor in the present invention may be such that a layer containing at least the naphthalocyanine compound of the present invention is provided on a conductive support, or preferably, at least a layer containing the naphthalocyanine compound of the present invention is provided on a conductive support. This layer is a stack of a layer and a charge transport layer, and the naphthalocyanine compound of the present invention is the main lateral component of the charge generation layer.

In order to form the naphthalocyanine of the present invention as a charge generation layer, naphthalocyanine is dissolved or dispersed in a solvent, coated and dried to form a pattern, and the naphthalocyanine compound and binder are dispersed or dissolved in a solvent and coated and dried. Further examples include adding a naphthalone anine compound, a binder, and other organic photoconductive substances as small amounts of components, dispersing or dissolving them, and coating and drying them.

Binders used at this time include polyvinyl butyral, polyarylate, polycarbonate, polyamide, polyurethane, polyester, polyvinyl acetate,
Examples include ethyl cellulose, which may be used alone or in combination of two or more.

The charge transport layer forming material used in the present invention includes, but is not limited to, poly-N-vinyl carbazole, polyvinyl anthracene, carbazoles, fluorenones, hydrazones, triazoles, quinones, and oxazoles. It's not a thing. The formation of this charge transport layer is carried out in the same manner as described above for the formation of the charge generation layer, and binders, solvents, etc. may be appropriately selected and used.

Examples of the conductive support in the present invention include an aluminum plate, an aluminum cylinder, an aluminum foil, and a plastic film in which a thin film or foil of a conductive metal such as aluminum is provided on the surface. The electrophotographic photoreceptor of the present invention can be provided with a protective layer on the surface layer of the photoreceptor, if necessary. The present invention will be specifically described below with reference to Examples.

(Example) Using Compound A and Compound B corresponding to each type of blood as described below, electrophotographic photoreceptors were prepared and evaluated by the following method.

First, 5 g of Compound A and 5 g of polyvinyl butyral were added to 90 m of n-butanol and mixed in a ball mill for 5 hours on an aluminum plate, and the mixture was bar coated to a dry film thickness of 0.5 μm. It was applied and dried to form a film. Next, a homogenized solution of 5 g of compound B and 5 g of polymethyl methacrylate added to 90 parts of toluene was applied onto the previously formed film by blade coating so that the dry film thickness was 25 μm. A dry film was formed.

Each of the electrophotographic photoreceptors obtained as described above was tested using an electrostatic copying paper tester SP-428 manufactured by Kawaguchi Electric ■.
Charging with a corona voltage of 5.5KV to increase the initial surface potential V0
The surface potential V after being left for 10 seconds in the dark
6 was measured, and then a semiconductor laser having an oscillation wavelength of 780 nm was irradiated to measure the half-reduction exposure amount (E%) and residual potential VR. The results of these measurements are shown in Table 1 for each electrophotographic photoreceptor.

In the notation of the compound, Et represents an ethyl group, Pr represents an n-propyl group, Bu represents an n-butyl group, and Me represents a methyl group.

Below is the margin (Example) (ml) ■, -S (CH2)2 SEt and incorporation (Na2) B compound (Na4) (?!l 3) ■.0 (CH2)20 Pr [Seed 5] Comparison Example [No. 6] Comparative Example [Blood 7] Temporary impregnation (effects of the invention) By incorporating the specific naphthalocyanine compound of the present invention into the photoreceptor layer, especially by incorporating it into the charge generation layer, the photosensitive properties can be improved. It was found that the electrophotographic photoreceptor can be made into an electrophotographic photoreceptor that has sufficient photoconductive sensitivity even for semiconductor lasers.

Claims (1)

[Claims] (1) In an electrophotographic photoreceptor comprising a layer containing at least an organic photoconductive substance on a conductive support, the organic photoconductive substance is a naphthalocyanine compound represented by the following general formula [1]. An electrophotographic photoreceptor characterized by the following. ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・
[1] (However, in the above formula, substituent X is different or the same -Z^
It is a group represented by 1-R^1-Z^2, where Z^1 represents oxygen or sulfur, and R^1 is a linear or branched alkylene having 1 to 18 carbon atoms, polyoxyalkylene, or Represents a divalent organic group selected from arylene having 6 to 14 carbon atoms or cycloalkylene having 4 or more carbon atoms,
Z^2 is halogen, alkyl having 1 to 8 carbon atoms, hydrogen,
-OR^2, -SR^3, -NR^4R^5 is an organic group selected from R^5, and R^2 to R^5 are linear or branched alkyl having 1 to 18 carbon atoms, or C6 ~14 alleles,
Indicates an organic group selected from alkenyl, polyoxyalkyl, and cycloalkyl having 4 or more carbon atoms. M represents a group selected from hydrogen, metal, metal oxide, metal halide, and metal hydroxide; n represents the number of substituents X; 0 to 2;
are integers, and may be the same or different. )