JPS59104657A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain always a good copied image with high sensitivty without any accumulation of potential even during repeated uses by incorporating a specified bisazo compd. in a carrier generating layer and a specified pyrazoline compd. in a carrier transfer layer. CONSTITUTION:A carrier generating layer incorporates a compd. represented by formula I or II in which Ar1, Ar2, Ar3 are each optionally substd. aromatic carbon ring; R1, R2 are each an electron acceptor group, such as CN; A is one of groups represented by formulae III-V, or the like; X is OH, optionally substd. amino, or -NHSO2-R6; R6 is optionally substd. alkyl or aryl; Y is H, halogen, optionally substd. alkyl, or the like; Z is an atomic group constituting an optionally substd. aromatic carbon or hetero ring; R3 is H, optionally substd. amino, or the like; A' is optionally substd. aryl; n is 1 or 2; and m is 0-4. A carrier transfer layer incorporates a compd. represented by formula VI in which R7, R8 are each alkyl or a group forming a ring together with N, and R9 is optionally substd. pyridyl or quinolyl. Thus, a long-lived photosensitive body is obtained by combining this carrier generating layer with the carrier transfer layer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the Seiko 4A photoreceptor, in which a photosensitive layer consisting of a combination of a carrier generation phase and a carrier transport layer is provided on a 4-porosity support.

To date, carrier-generating substances (hereinafter simply referred to as "carriers") that absorb visible light and generate charge carriers (hereinafter simply referred to as "carriers") have been developed.
Hereinafter referred to as rCGMJ. ) containing a carrier generation layer (hereinafter referred to as "cGLJ") and a carrier transport material (hereinafter referred to as rCTMJ) that transports either or both of positive and negative carriers generated in this CGL. Carrier Transport Jfj (rCT
My name is LJ. ) It has been proposed that the photosensitive layer of an electrophotographic photoreceptor is constructed by combining the following. In this way, by assigning the two basic functions necessary for a photosensitive layer, namely carrier generation and carrier transport, to separate layers, the range of materials that can be used in the composition of the photosensitive layer is widened. , it becomes possible to independently select materials or material systems that optimally perform each function, and by doing so, it is possible to achieve the characteristics required in the electrophotographic process, such as a high surface potential when #i is applied, It becomes possible to construct an electrophotographic photoreceptor' having excellent characteristics such as large charge retention capacity, high photosensitivity, and stability in repeated use.

Conventionally, as such a photosensitive layer, the following ones are known, for example.

(1) CGL made of amorphous selenium or cadmium sulfide
and CTL composed of poly-N-vinylcarbazole (7th configuration).

(2) CGL made of amorphous selenium or cadmium sulfide
and CTL containing 2,4.7-) dinitro-9-fluorenone are stacked.

(3) A structure in which a CGL made of a perylene derivative and a CTL containing an oxadiazole derivative are laminated (see US Pat. No. 3,871,882).

(4) CT containing CGL consisting of chlordiayan blue or methylscalyllium and pyrazoline derivative
A structure in which L is laminated (see Japanese Patent Laid-Open No. 51-90827).

(5) CGL made of amorphous selenium or its alloy and C containing a polyarylalkane aromatic amino compound
A structure in which TL and TL are laminated □
1 specification).

(6) CGL containing a perylene derivative and CTL containing a polyarylalkane aromatic amino compound
(Supplementary specification of Japanese Patent Application No. 53-19907).

In this way, there are many known photosensitive layers of this type, and when a conventional electrophotographic photoreceptor having such a photosensitive layer is repeatedly subjected to an electrophotographic process, The drawback is that the photosensitive layer suffers from severe electrical fatigue and has a very short service life.

For example, when subjected to repeated electrophotographic processes,
The potential history state of the electrophotographic photoreceptor is not maintained stably, resulting in stable image steel formation! Unable to obtain properties.

Further, the use of specific bisazo compounds as CGM is disclosed in, for example, JP-A-55-117151 and JP-A-54.
Although it is disclosed in Publication No. 145142, etc., this CG
Even in combination with CTM, which is said to be able to be combined with +vi, the above-mentioned drawbacks are still considerable.

As can be understood from this, a carrier-generating substance that is effective against a specific carrier-generating substance is not always effective against other carrier-generating substances, and a carrier-generating substance that is effective against a specific carrier-generating substance is not always effective against a specific carrier-transporting substance. An effective carrier generating substance is
It cannot be said that it is always effective compared to other carrier transport substances.If the combination of these two substances is inappropriate, not only will the photographic sensitivity become low, but also the discharge efficiency will be poor, especially at a low field. Therefore, the blue residual potential becomes large and i
In the case of fk evil, Km accumulates each time it is used repeatedly,
Practical - It becomes impossible to use it for child photography.

In this way, there is no lawful means of selecting a suitable combination of the constituent substances of the carrier generation phase and the constituent substances of the carrier transport phase, and it is necessary to practically determine an advantageous combination from a large group of substances. be.

The present invention has a photosensitizer comprising a combination of a carrier generation phase and a carrier transport phase, has high sensitivity, and can stably maintain the first-ranked history state even when repeatedly subjected to an electrophotographic process. An object of the present invention is to provide an electrophotographic photoreceptor that can consistently form good visible images.

The above purpose is to provide a photosensitive layer consisting of a combination of a carrier generation phase and a carrier transport phase on a transparent support.
In the euphotoreceptor, the carrier generation phase contains a bisazo compound represented by the following general formula (I) or the general formula [■'], and the carrier transport phase contains a pyrazoline compound represented by the following general formula (n). This is achieved by an electrophotographic photoreceptor characterized by containing.

General formula (i) General formula (wherein, Ar1, Ar2 and Ar5: each substituted or unsubstituted carbocyclic aromatic ring group, R1 or R2: each cryptographically attractive group, Y: hydrogen atom, halogen Atom, substituted or unsubstituted alkyl group, alkoxy group, carboxyl group, sulfo group, substituted or unsubstituted carbamoyl group or substituted or unsubstituted sulfamoyl group (however, when m is 2 or more, mutually different groups) ) 2: Atom group necessary to constitute a substituted or unsubstituted carbocyclic aromatic ring or a substituted or unsubstituted heterocyclic aromatic ring, R3: Hydrogen atom, substituted or unsubstituted amine group, substituted or unsubstituted carbamoyl group, carboxyl group or ester group thereof, A': substituted or unsubstituted aryl group, n: an integer of 1 or 2, m: an integer of 0 to 4 represent. ] General formula [■] 9 [In the formula, R7 and R8: the same or different residues forming a ring together with an alkyl group or a nitrogen atom, R9: unsubstituted pyridyl group, quinodyl group, or at least one alkyl group It represents a pyridyl group or a quinolyl group substituted with a group or an alkoxy group. ] Of the bisazo compounds represented by the general formula CI) t or the general formula
or represented by the general formula (I'm).

General formula (Ia) General formula CI'a) [wherein, Ar1, Ar2. Ar5 and A general formula [, I)
or the same as defined in the general formula [I]. ] More preferred are those represented by the following general formula (Ib) or CI'b).

General formula (Ib) N A N=N-Ar4 CH=CAr5 CH=CHAr
6 N=NA General formula (I'b) [wherein, general formula CI) or general formula [1], Ar4, Ar5 and Ar6: substituted or unsubstituted phenyl group and the substituent is selected from alkyl groups such as methyl group and ethyl group, alkoxy groups such as methoxy group and ethoxy group, halogen atoms such as chlorine atom and bromine atom, hydroxyl group and cyano group. is preferred. That is, in the present invention, the bisazo compound represented by the general formula CI) or the general formula [I is used as the CGM, and the pyrazoline compound represented by the general formula (I) is used as the CTM, and these are combined. This constitutes a photosensitive layer of a so-called functionally separated photoreceptor in which carrier generation and transport are performed using separate substances, respectively. As a result, it is possible to provide a photoreceptor that has high sensitivity, maintains a stable potential history state even when subjected to repeated electrophotographic processes, and can therefore always form good visible images. I can do it.

In addition, in the Seiko photographic photoreceptor of the present invention, wavelength 600 is suitable for hemorrhoids.
A large spectral sensitivity can be obtained even in the long wavelength region of ~700 nm, so for example, a helium-neon laser with a wavelength of 6328^ can be used as a light source for forming a latent image, and furthermore, the so-called potential tail cutting is good at low electric fields. Since the first position of the non-image area becomes zero or close to zero during development, good development can be performed even with a one-component developer consisting only of toner, which cannot obtain a large effective bias. Specific examples of the bisazo compound represented by (I) include those having the following structural formula, but are not limited thereto.

Exemplary compound F-IN
1 1
1--
-Ichino-
no-no1-1
1+l
)+IQ ri
QHl-4H Q ν Q
Love $+1”1 1 1 1-H
HH -no -no
−ノへ ri ＾to ~
■B
ψ C111 1-4+-+ I
+1-no -no
-Noo? -IeV3 Tototol 1
, 1' --- Q RIQ Specific examples of the bisazo compound represented by the above general formula [I] include those having the following structural formula, but are not limited thereto.

Exemplary compound ^ to ^- 1 +
1HI-L H-)
-ノ
-No--H ν ψ
Rino −no
-ノ+
H←→−−呵りQ り＋H＋−国 ′、4−も国CJ、 .

To /+ Ha dimension VI
K+(Cji
11 1 1-
〉−1) ()
() Cao
-Li11 1-I M
k-ichino
-ノ
()-c″′ one-no’-no the above general formula (
Specific examples of the pyranone compound represented by I[) include those having the following structural formula, but are not limited thereto.

Exemplary compounds (l-1) (u-2) (I[-3) (I[-4) (II-5) (II-7) (■-8) (It-9) (I-10) Next Next, the mechanical structure of the electrophotographic photoreceptor of the present invention will be explained.

In Example 1/C of the present invention, as shown in FIG. CTL3 containing the above-mentioned pyrazoline compound as a main component is formed by 1tRJ-shi, and the photosensitive layer 4 is constituted by these CGL2 and CTL3.

Here, as the material of the conductive support l, for example, a sheet of metal such as aluminum, nickel, copper, zinc, radium, silver, indium, tin, platinum, gold, stainless steel, brass, etc. can be used. . However, the invention is not limited thereto, and for example, as shown in FIG. 2, a conductive layer IB may be provided on an insulating base IA to constitute the conductive support 1. In this case, the base IA may be Suitable materials include paper, plastic sheets, etc., which are flexible and have sufficient strength against stress such as bending and tension. The conductive layer IB can also be provided by laminating metal sheets, vacuum depositing metals, or by other methods.

The CGL, 2b, by the already mentioned bisazo compound alone,
Or by adding a suitable binder resin to this,
Alternatively, it may be formed by adding a substance with high mobility to a specific or non-specific polar carrier, that is, CTM.As a specific method, the above-mentioned bisazo compound is suitably added to the support. A convenient method is to apply a solution in a suitable solvent or by dissolving or dispersing it together with a suitable binder resin and drying it.

In this method, examples of the solvent or dispersion medium include n-butylamine, diethylamine, ethylenediamine, isopropanolamine, monoethanolamine, triethanolamine, triethylenediamine, N,N-
Dimethylformamide, acetone, methyl ethyl ketone, cyclohexanone, benzene, toluene, xylene,
Chloroform, 1,2-dichloroethane, dichloromethane, tetrahydrofuran, dioxane, methanol, ethanol, impropatol, ethyl acetate, butyl acetate, dimethyl sulfoxide, and others can be used.

Further, as the binder resin, for example, polyethylene,
Addition polymer resins and polyaddition resins such as polypropylene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, polycarbonate resin, silicone resin, melamine resin, etc. , polycondensation type resins, and copolymer resins containing two or more of the repeating units of these resins, such as vinyl chloride-hinyl acetate copolymer resins, vinyl chloride-vinyl acetate-maleic anhydride copolymer resins In addition to insulating resins such as, polymeric organic semiconductors such as poly-N-vinylcarbazole can be mentioned. The ratio of this binder resin to the bisazo compound is 0 to 100%, particularly 0 to 10%
It is within the range of t%.

Appropriate CTM may be added to the CGL2 depending on safety.

The thickness of the CGL 2 formed as described above is preferably 0.005 to 20 microns, particularly preferably 0.005 to 20 microns, particularly preferably 0.
, 05-5 microns. If it is less than 0.005 microns, sufficient photosensitivity cannot be obtained, and if it exceeds 20 microns, sufficient light load retention cannot be obtained.

In addition, the CTL3 is caused by the above-mentioned pyracillin compound.
It can be formed in the same manner as CGL2 described above, ie alone or together with a binder resin.

Further, other CTMs may be included. This CTL
3 has a thickness of 2 to 100 microns, preferably 5 to 30 microns.

The Seiko photographic photoreceptor of the present invention may have other mechanical configurations. For example, as shown in FIG. 3, a suitable intermediate layer 5 may be provided on the conductive support 1, a CGL 2 may be formed through this, and a CTL 3 may be formed on this CGL 2. This intermediate layer 5 has a function of preventing free carriers from being injected from the conductive support 1 into the photosensitive layer 4 when the photosensitive layer 4 is charged, or to prevent the photosensitive layer 4 from being injected into the photosensitive layer 4 from the conductive support. It can function as an adhesive layer for integrally bonding. Materials for the intermediate layer 5 include metal oxides such as aluminum oxide and indium oxide, acrylic resins, methacrylic resins, vinyl chloride resins, vinyl acetate resins, epoxy resins, polyurethane resins, phenolic resins, polyester resins, alkyd resins, Single molecule resins such as polycarbonate resin, silicone resin, melamine resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, etc. can be used.

Further, as shown in FIG. 4, a CTL 3 is formed on the conductive support 1 with or without the intermediate layer 5, and the CTL 3 is
The photosensitive layer 4 may be formed by forming the CGL2 on the TL3.

Furthermore, it is possible to form a single layer photosensitive material 1- by incorporating a fraction of the bisazo compound described above into the carrier transport phase containing the pyrazolone compound described above to form a carrier generation phase. be.

Incidentally, various additives may be added to the layer constituting the photosensitive layer I- in the present invention, if necessary.

The embodiments of the present invention will be explained below, but the present invention is not limited thereto.

Example 1 A vinyl chloride-vinyl acetate-wet maleic acid copolymer [from Eslec MF-10J (manufactured by Tanezu Kagaku Kogyo Co., Ltd.) Consisting of thickness approximately 0
．． An intermediate layer of 0.05 microns was provided, and exemplified compound 4V (I-1
1.5 g of the bisazo compound shown in 6) was dispersed with 100 M of 1,2-dichloroethane in a ball mill for 8 hours, and the resulting dispersion was applied onto the intermediate layer using a doctor blade and thoroughly dried. A CGL with a thickness of about 0.5 microns was formed.

On the other hand, pyrazoline compound 11.25# shown as exemplified compound (II-2) and polycarbonate resin [Panlite L
-1250J (manufactured by Ondai Kasei Co., Ltd.) 15g in 1,2-dichloroethane 100-, and the resulting solution was
It was applied onto the GL using a doctor blade and sufficiently dried to form a CTL with a thickness of 12 microns, thereby producing an electrophotographic photoreceptor of the present invention. This will be referred to as "Sample 1".

Examples 2 to 8 Seven types of electrophotographic photoreceptors of the present invention were prepared in the same manner as in Example 1, except that in the formation of CGL and C'TL, the combinations shown in Table 1 below were used as exemplary compounds. Manufactured. These will be referred to as "Sample 2" to "Sample 8", respectively.

Table 1 Example 9 An intermediate layer was provided on a conductive support in the same manner as in Example 1, and 1.5Ii of a bisazo compound shown as exemplified compound (I-16) and a polycarbonate resin [Panlite L
-1250J of lfM and 1,2-dichloroethane 1
In addition to 0 (Il), dispersion was carried out using a ball mill for 12 hours, and the resulting dispersed charge was applied onto the intermediate layer using a doctor blade, and thoroughly dried to form a CG with a thickness of approximately 1 micron.
L was formed.

On this CGL, CTL was added in the same manner as in Example 1.
was formed, thereby producing an electrophotographic photoreceptor of the present invention. This will be referred to as "Sample 9."

Example 10 In the formation of CGL, the bisazo compound shown as Exemplified Compound (I'-5) was used, and in the formation of CTL, Exemplified Compound (II-5) was used as the pyrazoline compound.
An electrophotographic photoreceptor of the present invention was prepared in exactly the same manner as in Example 9 except that the material shown in ↓ was used. This is called “Sample 10”
shall be.

Comparative Example 1 Comparative electronics were prepared in the same manner as in Example 4, except that in the formation of CTL in Example 4, a pyrazoline derivative having the following structural formula was used instead of the pyrazoline compound represented by general formula (II'). A photographic photoreceptor was manufactured.

This is referred to as "comparative sample 1."

Comparative Example 2 Comparison was carried out in the same manner as in Example 4, except that in the formation of CTL in Example 4, an oxadiazole derivative having the following structural formula was used in place of the pyrazoline compound represented by the general formula CI[]. An electrophotographic photoreceptor was manufactured. This will be referred to as [Comparative Test I) 21.

Each of the Naruko photographic photoreceptors obtained as described above, Samples 1 to 10, Comparative Sample 1 and Comparative Sample 2 was tested using an "Electrometer 5P-428 Model" (Kawaguchi Electric Seisakusho IJ4). , its electrophotographic properties were investigated.

That is, the receptive position VA (V) when the photoreceptor surface is charged with a charging voltage of -6 KV for 5 seconds, and the potential Vr (initial 1st position) after dark decay for 5 seconds are required to attenuate downward. Exposure amount E3ACtux・sec), and dark decay rate (VA-V
l )/VAXI 00 (%).

The results are shown in Table 2.

Table 2 From the results in Table 2, it is clear that the electrophotographic photoreceptor of the present invention has high sensitivity.

In addition, each of Samples 1 to 10 and Comparative Samples 1 and 2 was transferred to a dry electronic copying machine r U-Bjx 2000RJ (
Konishi Roku Photo Industry Co., Ltd.) K was installed to perform continuous copying, and the black paper potential Vb (V) and white paper potential Vw (V) at an aperture value of 1.0 were measured using an "electrostatic voltmeter 144D-11) model". (manufactured by Monroe Electronics, Inc.), and was measured immediately before development. The results are shown in Table 3.

The black paper potential here refers to the surface potential of the photoreceptor when the above-mentioned copying cycle is performed using a black paper with a reflection density of 1.3 as an original, and the "white paper 4th" refers to the surface potential of the photoreceptor when a black paper with a reflection density of 1.3 is used as an original. It represents the surface potential of the photoreceptor.

Table 3 (However, in the table, ΔVb (V) and ΔVw (V) are the black paper potential Vb (V) and white paper potential Vw (V), respectively.
Indicates the amount of fluctuation, + in the amount of fluctuation represents an increase, and - represents a decrease. ) As is clear from the results in Table 3, the photoreceptor of the present invention maintains a stable potential history state even when repeatedly subjected to the Kameko photographic process, and produces visible images of good image quality. Many can be made cheaply.

[Brief explanation of the drawing]

FIG. 1 is an explanatory sectional view showing an example of the structure of the electrophotographic photoreceptor of the present invention, and FIG.
FIGS. 3 and 4 are explanatory cross-sectional views showing an example of coupling, and FIGS. 3 and 4 are explanatory cross-sectional views showing other structural examples of flaws in the photoconductor 4A of the present invention. 1... 4-layer support 2... Carrier generation layer (CGI) 3... Carrier ψ Hatake transport layer (CTL) 4... Photosensitive layer 5... Intermediate layer IA...
Insulating substrate IB... Conductive layer drawing B (no change in content) Figure 1 Figure 2 Figure 3 Figure 4 Procedural amendment, Kao. April 1980 260 Commissioner of the Japan Patent Office Kazuo Wakasugi 1, Indication of the case 1988 Patent Application No. 214038 2, Title of the invention Electrophotographic photoreceptor 3 Relationship with the amended person case Patent 1 tl' Applicant 79 Power f 1-26-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo; Su1 71ka1 (127) Mr. Konishiroku Photo Industry Co., Ltd.
Name (first name b) 4. Agent 218 1 koku (changed L for each) Procedural amendment (voluntary) March S, 1980 Commissioner of the Patent Office Kazuo Wakasugi Tono Indication of Case 19 1988 Patent Application No. 214038 2, Title of the invention: Electrophotographic photoreceptor 3, Relationship with the case of the person making the amendment Patent applicant address: 1-26-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Name (127) Konishiroku Photo Industry Co., Ltd. 4, Agent, Detailed Description of the Invention column of the specification to be amended, Contents of the amendment 1) The structural formula in Comparative Example 1 on page 83 of the specification is corrected as follows. [2] The structural formula of (B-13) on page 48 of the same is corrected as follows. [

Claims (1)

[Claims] l) A photoreceptor comprising a photosensitive layer comprising a combination of a carrier generation phase and a carrier transport phase provided on a conductive support, wherein the carrier generation phase is formed by the following general formula CI) or the general formula 1. A Seiko photographic photoreceptor comprising a bisazo compound represented by the formula [D'], wherein the carrier transport phase contains a pyrazoline compound represented by the following general formula [■]. General formula CI) 1 A -N=N-Ar 1-CH=C-Ar2-CH=C
H-Ar 3-N=N-A general formula [I'] [wherein, Ar1, Ar2 and Ar3: each substituted or unsubstituted carbocyclic aromatic ring group, Rlt or R2: each has sternic attraction group, 5-Nl(802-R6, Y: hydrogen atom, halogen atom, substituted or unsubstituted alkyl group, alkoxy group, carboxyl group, sulfo group, substituted or unsubstituted carbamoyl group, or monosubstituted or unsubstituted carbamoyl group) (However, the groups where m is 2 or more may be different groups.) 2: Substituted or unsubstituted carbocyclic aromatic ring or substituted or unsubstituted heterocycle Atom groups necessary to constitute an aromatic ring of the formula R3: hydrogen atom, substituted or unsubstituted amine group, substituted or unsubstituted carbamoyl group, carboxyl group or its ester group, to: substituted or unsubstituted Aryl group, n: 1 - represents an integer of 2, m represents an integer of 20 to 4.] General formula [[]9 (wherein, R7 and R43: respectively the same or different, an alkyl group or A residue that forms a ring with a nitrogen atom, R9: represents an unsubstituted pyridyl group, quinolyl group, or a pyridyl group or quinolyl group substituted with at least one alkyl group or alkoxy group.]