JPS63316866A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To enhance sensitivity and durability of a sensitive body by using a combination of a specified electric charge generating material and a specified charge transfer material. CONSTITUTION:The photosensitive body is obtained by successively laminating on a conductive supporting body 1, for example, optionally when needed, an interlayer 5, then a charge generating layer 2 containing the charge generating material represented by formula I, and a charge transfer layer 3 containing the charge transfer material represented by formula III, and in these formulae, A is a group of formula II; Y is carbamoyl or sulfamoyl; Z is an aromatic hydrocarbon ring or heterocyclic ring; R1 is H, alkyl, or the like; R2 is H, aryl, or the like; each of Ar1, Ar3, and Ar4 is phenyl or naphthyl; and Ar2 is phenylene or naphthylene, thus permitting the obtained photosensitive body to be high in sensitivity and small in fatigue deterioration even at the time of repeated uses for a long time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of R Tojo] The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having a photosensitive layer containing an organic photoconductive compound as a main component.

[Prior art]

Conventionally, as an electrophotographic photoreceptor (hereinafter simply referred to as a photoreceptor), a non-fi photoreceptor having a photosensitive layer mainly composed of an inorganic photoconductive compound such as selenium, zinc oxide, cadmium sulfide, or silicon has been widely used. Tesata. However, these are not necessarily satisfactory in terms of sensitivity, thermal stability, moisture resistance, durability, etc.1 For example, when selenium crystallizes, its properties as a photoreceptor deteriorate, making it difficult to manufacture. It crystallizes due to heat, fingerprints, etc., and its performance as a photoreceptor deteriorates. Cadmium sulfide also has problems with moisture resistance and durability, and zinc oxide has problems with durability, etc.

In order to overcome these drawbacks of inorganic photoreceptors, research and development of organic photoreceptors having photosensitive layers mainly composed of various organic photoconductive compounds has been actively conducted in recent years. describes an organic photoreceptor comprising a photosensitive layer containing poly-N-vinylcarbazole and 2.4.7-)Lielow-9-fluorenone. However, this photoreceptor is not necessarily satisfactory in terms of sensitivity and durability.In order to improve these drawbacks, charge generation function and charge transport +1! Attempts are being made to develop organic photoreceptors with higher performance by sharing the photoreceptor with different materials. Many studies have been conducted on such so-called function-separated type photoreceptors because each material can be selected from a wide range and a photoreceptor having arbitrary performance can be produced relatively easily.

As a result, various azo compounds have been developed and put into practical use as charge generating substances. On the other hand, regarding charge transport materials, for example, JP-A-51-94829 and JP-A-52-7223
No. 1, No. 53-27033, No. 55-52063,
A wide variety of substances have been proposed, as disclosed in Japanese Patent No. 58-65440.

[Problem that the invention seeks to solve]

Although some photoreceptors fabricated using charge-generating materials and charge-transporting materials as described above exhibit relatively excellent electrophotographic performance, their sensitivity is still insufficient and their light or electrical loads are limited. It does not fully satisfy practical requirements because it has low durability and causes instability and deterioration of performance during repeated use. There has been a desire to develop a photoreceptor that has high performance and exhibits stable performance over long periods of use.

[Purpose of the invention]

The object of the present invention is to solve the above-mentioned situation by using a charge generating material (CG).
14) and a charge transport material (CT14), it is an object of the present invention to provide an electrophotographic photoreceptor with high sensitivity and high durability.

In particular, it is an object of the present invention to provide a highly durable electrophotographic photoreceptor that exhibits stable characteristics with very little fatigue deterioration and no decrease in sensitivity even after repeated use.

[Structure of the invention]

The object of the present invention is to form the following general formula [1] on a conductive support.
This is achieved by an electrophotographic photoreceptor characterized by having a photosensitive layer containing as an active ingredient at least one of the compound represented by the formula (II) and the compound group represented by the general formula (II).

General formula (1) However, in the formula, R1 represents a hydrogen atom, an alkyl group, an alkoxy group, an amide group, an aryloxy group, or a halogen atom, and R2 represents a hydrogen atom, an alkyl group, or an aryl group.

^r3. ^r31^r represents a 7enyl group or a naphthyl group, and ^"2 represents a phenylene group or a naphthylene group.

n represents an integer of 0 or 1.

Furthermore, the above R1-R2 and ^"1 to ^r may have a substituent.

General formula (n) However, in the formula, A is, and Y represents a carbamoyl group or a sulfamoyl group.

Z represents a carbocyclic aromatic ring or a heterocyclic aromatic ring; @Y and Z may have a substituent.

Next, specific compounds represented by the general formula (1) and (Ill) will be illustrated.

Exemplary compound (general formula [1]) ■ -12 ■ -13 ! -16 ■ -17 ■ -18 ■ -19 r〃 ■ -25 ■ -26 ■ -27 L ■ -28 Summer -29 ■ -31! -32 ■ -33 ■ -36 ,ノ；'・ Below margin E...
Minister H.
Nakaguchi
- -1 agony
…
==four
...CTN used in the present invention
and CGN generally do not have film-forming properties, so
The photosensitive layer may be formed by combining various binders.

Any binder can be used at this time, but it is preferable to use a hydrophobic, high electric conductivity, electrically insulating film-forming polymer. Examples include, but are not limited to, the following:

(1) Polycarbonate (2) Polyester (3) Methacrylic resin (4) Acrylic resin (5) Polyvinyl chloride (6) Polyvinylidene chloride (7) Polystyrene (8) Polyvinyl acetate (9) Styrenic copolymer resin (e.g. styrene -butanoene copolymer, styrene methyl methacrylate copolymer) (to) 7-crylonitrile copolymer resin (e.g. vinylidene chloride-7-crylonitrile copolymer, etc.) (11) Vinyl chloride-vinyl acetate copolymer (12) )
Vinyl chloride-vinyl acetate-maleic anhydride copolymer (13) Silicone resin (14) Silicone-fluid resin (15) Phenol resin rm (e.g. phenol-formaldehyde, -resol-formaldehyde resin, etc.) (16) Styrene Flukyd Resin (17) Poly-
N-vinylcarbazole (18) Polyvinyl butyral (19) Polyvinyl 7olmal (20) Polyhydroxystyrene These binders can be used alone or in a mixture of two or more.

As shown in FIGS. 1 and 2, the photoreceptor of the present invention has a charge generation layer containing CGM as a main component on a conductive support 1.
(hereinafter referred to as CGL) 2 and a charge transport layer (hereinafter referred to as CTL) 3 containing CTH as a main component. As shown in FIG. 3 and Pt54, this photosensitive layer 4 may be provided through an intermediate layer 5 provided on the conductive support 1. When the photosensitive layer 4 has a two-layer structure in this way, A photoreceptor having the best electrophotographic properties is obtained. Further, in the present invention, as shown in FIG. 5 and FIG. It may be provided directly on 1 or via an intermediate layer 5.

Furthermore, a protective layer (hereinafter OC
(marked as L) 8 may be provided.

Here, when the photosensitive layer 4 has a two-layer structure, CGL2 and CT
Which of L3 is to be used as the upper layer is determined depending on whether the charging polarity is positive or negative. That is, when forming a negatively charged photosensitive layer, it is advantageous to use the CTL 3 as the upper layer, since CTN in the CTL 3 is a substance that has the ability to transport holes.

It also constitutes the photosensitive layer 4 having a two-layer structure (C:L2, CT
L3 is a conductive support 1, CTL3 or C that serves as the lower layer surface, and CTL4°C is applied directly on L2 or after providing an intermediate layer such as an adhesive layer or a barrier layer as necessary.
Depending on the characteristics of GH, it can be formed by the following method.

(1) Vapor phase deposition method (2) Paint application method a) A method of applying a solution paint in which CGM and CTN are dissolved in a suitable solvent.

b) A method of coating C with a dispersion coating obtained by forming fine particles of M and CTM in a dispersion medium using a ball mill, homomixer, etc., and mixing and dispersing them with a binder as necessary.

The vapor deposition method includes a vacuum evaporation method, a sputtering method, an ion plating method, a CVD method, etc., and the paint application method includes a dipping method, a spray method, an air doctor method, a doctor spray method, a reverse roll method, etc. An appropriate method is selected depending on the physical properties of the paint.

The thickness of CGL 2 formed in this way is 0.0
It is preferably 1 to 5 microns, more preferably 0.05 to 3 microns.

The thickness of the CTL 3 can be changed as necessary, but it is usually preferably 5 to 30 microns.
Regarding the composition ratio in 3, it is preferable that the binder is 0.8 to 1 part of lO'rlLi to 1 part of CTH, but when forming the photosensitive layer 4 in which fine powder CGM is dispersed, C(: It is preferable to use the binder in an amount of 5 parts by weight or less per 1 part by weight of N.

In addition, when CGL2 is configured as a dispersed type using a binder, 5 layers of binder are applied to 1 part by weight of C1;M! The layer structure of the photosensitive layer of the photoreceptor of the present invention is preferably 81M or less as described above.
There are two types: CTL and CTL, which form the surface layer.
Incorporating one or more electron-accepting substances into either the single-layer photosensitive layer or OCL, or multiple layers, for the purpose of improving sensitivity, reducing residual potential or fatigue during repeated use, etc. Can be done.

Electron-accepting substances that can be used in the photoreceptor of the present invention include:
For example, succinic anhydride, maleic anhydride, nobromaleic anhydride, 7-talic anhydride, tetrachlor 7-talic anhydride,
Tetrabromo 7-talic anhydride, 3-nitro 7-talic anhydride,
4-Nitro-7tallic anhydride, pyromellitic anhydride, mellitic anhydride, tetracyanoethylene, tetracyanoquinone methane, O-dinitrobenzene, -dinitrobenzene,
113151-trinitrobenzene, varanitrobenzonitrile, picryl chloride, quinone chlorimide,
Chloranil, pullmanil, 2-methylnatamine, dichlorodicyanoparabenzoquinone, anthraquinone, dinitroanthraquinone, trinitrofluorenone, 9-
Fluorenonedene [dicyanomethylenemalo7cinitrile], polynitro-9-fluorenonedene [dicyanomethylenemalo7cinitrile], picric acid, 0-nitrobenzoic acid, p-nitrobenzoic acid, 3.5-nonitrobenzoic acid, penta Fluorobenzoic acid, 5-nitrosalicylic acid,
Examples include 3,5-dinitrosalicylic acid and 7-talic acid.

Furthermore, silicone oil may be present as a surface modifier, and an ammonium compound may be contained as a durability improver.

Furthermore, ultraviolet absorbers, antioxidants, etc. may be used. Preferred ultraviolet absorbers include benzoic acid, stilbene compounds, etc. and their derivatives, triazole compounds, imiguzole compounds, tri7one compounds, coumarin compounds, and Nitrogen-containing compounds such as sadiazole compounds, thiazole compounds and derivatives thereof are used.

Examples of the antioxidant include hindered phenol, hindered amine, paraphenylenenoamine, aryl alkane, hydroquinone, spirochroman, spiroindanone and derivatives thereof, organic sulfur compounds, organic phosphorus compounds, and the like. Specific examples of these compounds include Japanese Patent Application No. 61-182866, Japanese Patent Application No. 61-188975,
No. 61-195878, No. 61-157644, No. 61-195879, No. 61-162867, No. 6
No. 1-204469, No. 61-217493, No. 61
It is described in No. -217492 and No. 61-221541.

Next, the binder used in the OCL of the present invention has a volume resistivity of 10"Ωc or more, preferably 101jΩc11 or more,
More preferably, a transparent resin having a resistance of 10I3ΩC or more is used. The binder preferably contains a small amount (50% by weight or more) of a resin that hardens by light or heat. Also, the OCL contains resins for the purpose of improving processability and physical properties (preventing cracks, imparting flexibility, etc.). If necessary, thermoplasticity 0 (
It can contain less than 50% by weight of fat.

Further, the intermediate layer functions as an adhesive layer or a barrier layer, and the binder! In addition to fats, for example, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, casein,
N-flucoxymethylated nylon, starch, etc. are used.

As the conductive support 1 used in the construction of the electrophotographic photoreceptor of the present invention, the following are mainly used, but the invention is not limited thereto.

1) Metal plates such as aluminum plates and stainless steel plates.

2) A thin layer of metal such as aluminum, palladium, or gold is provided on a support such as paper or plastic film by lamination or vapor deposition.

3) A layer of a conductive compound such as a conductive polymer, indium oxide, or tin oxide is provided on a support such as paper or a plastic film by coating or vapor deposition.

〔Example〕

EXAMPLES The present invention will be explained below with reference to Examples, but the embodiments of the present invention are not limited thereby.

Example 1 A 0.1 μm thick film made of vinyl chloride-vinyl acetate-maleic anhydride copolymer [S-LEF NF-10J (Sekisui Chemical Co., Ltd. W)] was placed on a conductive support made by vapor-depositing aluminum on a polyester film. An intermediate layer was created.

On top of that, 1 part by weight of exemplified compound It-2 as CCM, 1 part by weight of polymethyl methacrylate resin 1 Elbasite 201
0J (du Port company 1) 0.51 with Okibe, 1
, 2-dichloroethane and dispersed in a ball mill for 24 hours, the solution was coated so that the film thickness after drying was 0.4 μm to form a CCL.

Exemplified compound 1-2.7. ! l Mound and polycarbonate resin [Panlite L-12501
(manufactured by Teijin Chemicals) and 1,2-dichloroethane 120
The electrophotographic photoreceptor of the present invention was prepared by coating a solution dissolved in parts by weight so that the film thickness after drying was 15 μm to form a CTL.

Regarding this electrophotographic photoreceptor, electrostatic copying paper testing device i!
The electrophotographic characteristics were measured by a dynamic method using rSP-428J (newly manufactured by Kawaguchi Electric Seisakusho).

That is, the surface of the photosensitive layer of the photoreceptor was charged with a charging voltage of -0 kV for 5
Surface potential V when charged for seconds Next, irradiate the photoreceptor surface with light from a tungsten lamp so that the illumination intensity is 351 ux, and reduce the surface potential of -aoov to 1! Exposure iE::: and 30tux・se required to decompress to 00V
The surface potential (residual potential) ■ after irradiation with an exposure amount of c was determined for each.

Further, similar measurements were repeated 100 times. The results are shown in Table 1.

Comparative Example I The electrophotographic photoreceptor of the present invention of Example 1 had the same properties as in Example 1 except that a stilbene derivative having the following structure was used as the CTM. Compared to the photoreceptor of Comparative Example 1, this photoreceptor was markedly superior in sensitivity, residual potential characteristics, and repetition stability.

Examples 2 to 10 Exemplary compounds (1-4), (1-6), (I
-8), (1-13), (1-15), (1-18),
An electrophotographic photoreceptor of the present invention was produced in the same manner as in Example 1 except that (1-24) (+-28) and (1-35) were used.

Measurements were performed on these electrophotographic photoreceptors in the same manner as in Example 1. The results are shown in Section 2a.

Margins below Table 2 Margins below Example 11 Consisting of vinyl chloride-vinyl acetate-maleic anhydride copolymer [Eslec NF-104] on a conductive support made by laminating aluminum foil on a polyester film. An intermediate layer having a thickness of Q and 1 μm was provided.

On top of that, an exemplified compound as CGM [1-10.1 parts by weight and polycarbonate resin [Panrai] L-1250
41 weight and 11 parts by weight were added to 1.2-Fukuro 01 weight 2100 parts by weight, and the liquid was dispersed for 5 hours by sand grinding, and the liquid was applied so that the film thickness after drying was 0.4 μ- to form CGL. did.

Furthermore, the exemplified compound [-,5,7,5
Weight parts and polycarbonate resin [Panrai] K-130
The electrophotographic photoreceptor of the present invention was prepared by coating a solution prepared by dissolving 10 parts by weight of 0J in 1 part by weight of 120 parts by weight of 1,2-acoustic ethane so that the film thickness after drying would be 15 μm to form a CTL. did.

The same measurements as in Example 1 were performed on this electrophotographic photoreceptor, and the results shown in Table 3 were obtained.

Comparative Example 2 A comparative photoreceptor was prepared in the same manner as in Example 11, except that a bisazo pigment represented by the following structural formula was used as CGM.

rll.

When this comparative photoreceptor was measured in the same manner as in Example 1, the results shown in Table 3 were obtained.

ttrJ3 Table Examples 12-20 cc? Exemplary compounds (■-1), (II-5>
, (II-6), (n -9), (It-12), (E
l-15), (■-16), (■-18), (■-20
) An electrophotographic photoreceptor of the present invention was produced in the same manner as in Example 11 except that the following was used.

These electrophotographic photoreceptors were measured in the same manner as in Example 1, and the results are shown in Table 4.

Example 21 An intermediate layer made of a vinyl chloride-vinyl acetate-maleic anhydride copolymer was coated on a cylindrical aluminum drum having a diameter of 80φ by a dipping method.

On top of that, 1 part by weight of exemplified compound ■-17 as CGM and polymethyl methacrylate resin [Guillanard 88-8
0J (manufactured by Mitsubishi Rayon Co., Ltd.) 1 mfi part and 1°2-
After drying the liquid, which was added to 130 parts by weight of dichloroethane and dispersed in a ball mill for 24 hours, s! A CCL was formed by dipping coating to a thickness of 0.4 μ-.

Next, as CTN, 2.7.5 parts by weight of exemplified compound 1 and polycarbonate resin [Panlite K-1300J
10 parts by weight of 1,2-dichloroethane i5om m
The electrophotographic photoreceptor of the present invention was prepared by applying a solution dissolved in S to a CTL using the same dipping method so that the film thickness after drying was 18 .mu.m.

Electrophotographic copying of this electrophotographic photoreceptor $11'U-Bix
1550MRJ (Konishi Roku Photo Industry Co., Ltd.!) and copied the image, we obtained a copied image that was faithful to the original image, had high contrast, and excellent gradation.This did not change even after repeating it 50,000 times. There wasn't.

Comparative Example 3 A comparative photoreceptor was prepared in the same manner as in Example 21, except that a bisazo pigment represented by the following structural formula was used as the CCM, and a stilbene conductor represented by the following structural formula was used as the CTM.

When images were copied on this comparative photoreceptor in the same manner as in Example 21, fogging began to become noticeable from around the to, ooo copy and after 15,000 fubi.
The ripple was increased, and only images with low dust resistance were obtained.

'Xm Example 23 An electrophotographic photoreceptor of the present invention was prepared in the same manner as in Example 1, except that Exemplary Compound 1-4 was used as the CTM. This photoreceptor was used for electrophotographic copying 1fi "U-Bix1550M".
The sample was mounted on an RJ and only paper feeding was omitted, and charging and exposure were repeated to observe changes in potential characteristics. The results are shown in section s12.

Here, V. represents the potential at the developing device position of the portion corresponding to the original density 1.3, and Vw represents the potential at the developing device position of the portion corresponding to the original density O.

Comparative Example 4 A comparative photoreceptor was prepared in the same manner as in Example 23, except that the following stilbene derivative was used as the CTM.

Regarding this comparative photoreceptor, measurements similar to those in Example 23 were carried out, and the results are shown in Section 5a.

Below is a blank space Table 5 Example 24 A conductive electrode support made by vapor-depositing aluminum on a polyester film and made of vinyl chloride-vinyl acetate-maleic anhydride copolymer [Essure 7ri MF-10] with a thickness of 0
．． A middle layer based on the 1μ theory was established.

Then, exemplified compound 1-5.7.5 is added thereon as CTM.
Weight parts and polycarbonate resin [Panlite K-13
00J 10 parts by weight and Tetrahydro 7ran 100ii
A CTL was formed by applying a solution dissolved in ias so that the film σ after drying was 15 μm.

Furthermore, as a CCM, exemplified compound ■-2011 parts polycarbonate resin "Panrai" L-1250J
2 parts by weight As CTM, 70 parts by weight of cycloethane and 11 parts of 30ffi of 1.1.2-) dichloroethane were added to 51.5 parts by weight of Exemplified Compound 1, and the resulting solution was dispersed in a III ball mill for 24 hours. After drying. An electrophotographic photoreceptor of the present invention was prepared using a CGL having a thickness of 5 μm.

Measurements were carried out in the same manner as in Example 1, except that the charging voltage of this electrophotographic photoreceptor was changed to +6 kV, and the results shown in Table 6 were obtained.

As is clear from the results shown in Table tjS6, the electrophotographic photoreceptor of the present invention has excellent acceptance potential, sensitivity, and residual potential characteristics, and is particularly excellent in repeated stability.

(Effect of the invention) By combining the CGN and CTM of the present invention, CGM
A highly durable photoreceptor with excellent carrier injection efficiency, high sensitivity, and extremely low fatigue deterioration can be obtained.

In particular, it is possible to obtain a highly durable electrophotographic photoreceptor that exhibits extremely little fatigue deterioration even after repeated use in the dark and exhibits stable characteristics without a decrease in sensitivity.

[Brief explanation of the drawing]

1 to 6 are sectional views showing examples of the mechanical structure of the electrophotographic photoreceptor of the present invention, respectively. 1... Conductive support 2... Carrier generation layer 3.
...Carrier transport layer 4...Photosensitive layer 5...Intermediate layer
6... Layer containing a carrier transporting substance 7... Carrier generating substance 8... Protective layer Applicant Konishiroku Photo Industry Co., Ltd. Figure 2

Claims (1)

[Scope of Claims] It is characterized by having a photosensitive layer containing at least one of a compound represented by the following general formula [I] and a compound represented by the general formula [II] as an active ingredient on a conductive support. Electrophotographic photoreceptor. General formula [I] ▲ Numerical formulas, chemical formulas, tables, etc. group, represents an aryl group. Ar_1, Ar_3, Ar_4 represent a phenyl group or a naphthyl group, and Ar_2 represents a phenylene group or a naphthylene group. n represents an integer of 0 or 1. ] General formula [II] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [However, in the formula, A is ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and Y represents a carbamoyl group or a sulfamoyl group. Z represents a carbocyclic aromatic ring or a heterocyclic aromatic ring. ]