JPS59100446A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a photosensitive body high in sensitivity by incorporating a bisazo compd. in a carrier generating phase and a hydrazone compd. in a carrier transfer phase. CONSTITUTION:The bisazo compd. incorporated in the carrier generating phase is represented by general formula III in which Ar1, Ar2, Ar3 are each an aromatic homogeneous carbon ring group; R1 is an electron acceptor; A is represented by one of general formulae I ; R3, R4, R5 are each H, alkyl, or the like; Y is H, halogen, alkyl, alkoxy, or the like; Z is a homogeneous carbon or heterocyclic aromatic ring; R2 is H, amino, carbamoyl, or the like; A' is aryl; (n) is 1 or 2; and (m) is an integer of 0-4. The hydrazone compd. incorporated in the carrier transfer layer is represented by formula II in which R6 is methyl, ethyl, 2-hydroxyethyl, or 2-chloroethyl, and R7 is methyl, ethyl, benzyl, or phenyl. In formula III, X is hydroxy, -N(R3)(R4), or -NHSO2-R5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic photoreceptor in which a photosensitive layer comprising a combination of a carrier generation phase and a carrier transport phase is provided on a conductive support.

To date, carrier-generating substances (hereinafter simply referred to as "carriers") that absorb visible light and generate charged carriers (hereinafter simply referred to as "carriers") have been developed.
Hereinafter referred to as "CGM". ) containing a carrier generation layer (hereinafter referred to as "CGL"), and a carrier transport material (hereinafter referred to as "CTM") that transports either or both of positive or negative carriers generated in this CGL. A carrier transport layer (hereinafter referred to as "CTL") comprising:

) to form a photosensitive layer of an electrophotographic photoreceptor. In this way, the two necessary processes in the photosensitive layer are the generation of carriers and their transport.
By allocating the two basic functions to separate layers, the range of materials that can be used to construct the photosensitive layer is widened, and it is also possible to independently select materials or material systems that optimally perform each function. In addition, by doing so, it is possible to meet the various properties required in the electrophotographic process, such as high surface potential when charged, high potential retention ability, high photosensitivity, and high stability during repeated use. It becomes possible to construct an electrophotographic photoreceptor having excellent characteristics.

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

(1) CGL made of amorphous selenium or cadmium sulfide
A structure in which these are layered.

(2) CGL made of amorphous selenium or cadmium sulfide
and CTL containing 2,4,7-trinitro-9-fluorenone are laminated.

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

(4) A structure in which CGL made of chlordiane blue or methylscalyllium and CTL containing a pyrazoline derivative are laminated (see JP-A-51-90827).

(5) Made of amorphous selenium or its alloy ('()l,
and polyarylalkane aromatic aminated compound 4C
Contains (composition consisting of Sol'L and Bonga Formation (Patent Application 1984)
-147251 Specification 1! ).

(6) A structure in which C(JL containing a perylene derivative) and CTL also containing a polyarylalkane aromatic amino compound are laminated (Japanese Patent Application No. 19907/1983).

As described above, many photosensitive layers of this type are known; When the photosensitive layer is subjected to [Offering/ζ.

Sometimes, the potential history state of the electrophotographic photoreceptor is not stably maintained, making it impossible to obtain stable image forming characteristics.

1'Although use as a specific bisazo compound (5CUM is disclosed in, for example, JP-A-55-117151, JP-A-54-145142, etc.), it can be used in combination with UUM. Even in combination with C'14, which is considered to be the same, the above-mentioned drawbacks are still considerable.

As can be seen from this, a carrier transport material that is effective against a certain type of carrier-generating substance is not always effective against other carrier-generating substances, and It cannot be said that a carrier-generating substance that is effective against a substance is always effective against other carrier-generating substances.

If the combination of both substances is inappropriate, the electrophotographic sensitivity will not only be low, but also the discharge efficiency will be poor especially in low electric fields, so the residual output marked with Fr will be poor, and in the worst case, repeat Is it practical because the electric potential accumulates every time you use it? It will no longer be possible to use it as a photo of T'L.

In this way, there is no legal way to select a suitable combination of the constituents of the carrier generation phase and the constituents of the carrier transport phase. It needs to be dimensional.

Heather invention cavity, carrier generation 1st. It is equipped with a photosensitive layer consisting of a carrier transport phase and a total combination of t, and has a thick structure, and furthermore, the potential history state is stable even when it is applied in a continuous manner and subjected to a photolithography process. The object of the present invention is to provide an electrophotographic photoreceptor that can maintain and consistently produce good image quality.

The above object is to provide an electrophotographic sensitive body comprising a photosensitive layer formed of a combination of a carrier generation phase and a carrier transport phase on a conductive support, wherein the carrier generation phase is represented by the following general formula [1]. Containing the bisazo compound shown in 1. This is achieved by an electrophotographic sensitive material characterized in that the carrier transport I1 contains a hydrazone compound represented by the following general formula (Jl) (+1').

General formula I].

[In the formula, Ar1, Ar2 and Ar3': substituted and unsubstituted carbocyclic aromatic ring groups, R1: electron-withdrawing group, X: hydroxy group, or provided that R3 and R4 are each hydrogen atom, substituted, Unsubstituted alkyl group, R5 is substituted or unsubstituted alkyl group or substituted or unsubstituted aryl group, Y: hydrogen atom, halogen atom, substituted or unsubstituted alkyl group, alkoxy group, carboxyl group, sulfo group, substituted , unsubstituted carbamoyl group or substituted, unsubstituted sulfamoyl group, (, however, when m is 2 or more, are different from each other,
It's okay to meet someone. ).

Z: Atom group necessary to constitute a substituted, substituted carbocyclic aromatic ring or a substituted or unsubstituted heterocyclic aromatic ring M2: Hydrogen atom, substituted or unsubstituted amine group, Substitution, 1.
An unsubstituted carbamoyl group, a carboxyl group or a derivative thereof, a ster group, A': a substituted or unsubstituted aryl group, n: an integer of 1 or 2, m: an integer of 0 to 4. ]・General formula Ln) [In the formula, R6: represents a stell group, an ethyl group, a 2-hydroxyethyl group, or a 2-chloroethyl group; R7: represents a methyl group, an ethyl group, a benzyl group, or a phenyl group. ] Among the bislazo compounds represented by the general formula [■], preferred are 0. It is represented by the general formula [■a].

General formula [■a] [Wherein, Ar1, Ar2, Ar3 and A: Same as defined in general formula [■]. ] More preferred are those represented by the following general formula [■b].

General formula [■b] [In the formula, A: Same as defined in general formula [■], Ar4Ar5 and Ar6: substituted or unsubstituted phenyl group, and substituents include methyl group, ethyl group, etc. The group is preferably selected from alkyl groups, alkoxy groups such as methoxy groups and ethoxy groups, halogen atoms such as chlorine atoms and bromine atoms, hydroxyl groups and cyano groups. ] That is, in the present invention, the bisazo compound represented by the general formula [■] is used as a CGM, and the bisazo compound represented by the general formula [■] is used as a CGM.
By using the hydrazone compound shown in [2] as a CTM and combining them, a photosensitive layer of a so-called functionally separated photoreceptor in which carrier generation and transport are performed by separate substances, respectively, is constructed.

As a result, it is possible to provide an electrophotographic 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.

Specific examples of the hydrazone compound represented by the general formula [■] include those having the following structural formula, but are not limited thereto.

Exemplary Compounds Next, the mechanical structure of the electrophotographic photoreceptor of the present invention will be explained.

In one example of the present invention, as shown in FIG. 1, a CGL2 containing the general bisazo compound as a main component is formed on a conductive support 1, and a general hydrazone compound is formed on the CGL2 as a main component. The photosensitive layer 4 is formed by laminating CGL3 containing the above components, and these CGL2 and CTL3 constitute the photosensitive layer 4.

Here, as the material of the conductive support 1, for example, a sheet of metal such as aluminum, nickel, copper, zinc, palladium, silver, indium, tin, platinum, gold, stainless copper, or brass can be used. However, the invention is not limited to these. For example, as shown in FIG. 2, a conductive layer 1B may be provided on an insulating substrate 1A to form a conductive support 1. As for paper, plastic sheets, etc., it is better to have 0" i (jt), but also lack the strength of T1-min against stress such as bending and tension. Also, the conductive material η113 is It can be provided by laminating the gold A'' percent or by vacuum depositing the metal, or by other methods.

The CGL can be produced by the aforementioned bisazo compound alone, by adding a suitable binder resin thereto, or by further transferring to a carrier of specific or non-specific polarity.
A material with a large effect, that is, CTM, can be formed by adding ζ. 1. Specific method and 1. So,
A method of dissolving or dispersing the bisazo compound described above in a suitable solvent alone or together with a suitable binder resin and drying it is conveniently used. .

In this method, the solvent or dispersant is
For example, 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, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, and others. be able to. , In addition, as the binder resin, for example, polyethylene,
Addition polymerization 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. In addition to poly-N
- Polymeric organic semiconductors such as vinyl carbazole can be mentioned. The ratio of this binder resin to the bisazo compound is 0 to 100% by weight, particularly 0 to 10% by weight.
% by weight.

An appropriate amount of CTM may be added to the CGL2, if necessary.

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 sensitivity cannot be obtained, and if it exceeds 20 microns, sufficient charge retention cannot be obtained.

Moreover, the CTL3 is caused by the above-mentioned hydrazone 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 electrophotographic 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 a conductive support l, a CGL2 may be formed through this, and a CTL3 may be formed on this CGL2. 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 a function of preventing the photosensitive layer 4 from being integrally connected to the conductive support. It can have a function as an adhesive layer for adhering to. Examples of materials for the intermediate layer 5 include metal oxides such as aluminum oxide and indium oxide;
Acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, polycarbonate resin, shirikonjushi, melamine resin, vinyl chloride-vinyl acetate copolymer resin, chloride A polymeric material such as vinyl-vinyl acetate-maleic anhydride copolymer resin 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 also possible to form a single-layer photosensitive layer by dispersing the general bisazo compound in a carrier transport phase containing the general hydrazone compound to form a carrier generation phase.

In addition, various additives may be added to the layer constituting the photosensitive layer in the present invention (-) as necessary. In the following, the examples of the present invention will be described as follows. l'' is limited (・-1--Door Example 1 Aluminum gold vapor-deposited +9 J,
, i<-+ support (41K, V hinyl chloride-acid-resistant vinyl-
A1 unit for hot water malein'r [Sresoku MF-10
-1 (manufactured by Wazu Kagaku Kamizan Co., Ltd.) with a thickness of about 0.05 mm I" σ) was provided, and 1.5 g of the bisazo compound shown as Exemplified Compound (1-5) was added to the 1.2- dichloroethane 1
00ml using a ball mill for 8 hours, and the resulting dispersion was applied onto the intermediate layer using a doctor blade. After drying thoroughly, a CGL with a thickness of about 0.5 microns was cut out.

On the other hand, 11.25 g of the hydrazone compound shown as the exemplified product (II-5) and the polycarbonate resin "Panlite L
1250'' (manufactured by Teitetsu Kasei Co., Ltd.) in 100 ml of 1,2-dichloroethane, and the resulting solution was dissolved in the CG
It was coated onto L 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 5 In the formation of CGL, exemplary compounds (1-7), (1-9), (1-16) and (1-4) were used as bisazo compounds.
Four types of electrophotographic photoreceptors of the present invention were manufactured in exactly the same manner as in Example 1 except that each of the materials shown in 5) was used. These will be referred to as "Sample 2" to "Sample 5", respectively.

Examples 6 to 9 In the formation of CTL, exemplary compounds (■-2), (■-3), (■-6) and (■-7) were used as hydrazone compounds.
) A 4-axis electrophotographic photoreceptor of the present invention was manufactured in the same manner as in Example 1 except that each of the materials shown in (a) was used. These will be referred to as "Sample 6" to "Sample 9", respectively.

Example 10 An intermediate layer was provided on a conductive support in the same manner as in Example 1, and 1.5 g of the bisazo compound shown as exemplified compound (1-5) and polycarbonate resin "Panlite L-1" were added.
15g of ``250'' and 100m of 1,2-dichloroethane
The resulting dispersion was applied onto the intermediate layer using a doctor blade and thoroughly dried to form a CGL with a thickness of about 1 micron.

On this CGL, CTL was added in the same manner as in Example 1.
An electrophotographic photoreceptor of the present invention was manufactured in a similar manner. This will be referred to as "sample 10."

Comparative Example 1 A comparative electrophotographic photoreceptor was produced in the same manner as in Example 1, except that a pyrazoline derivative having the following structural formula was used in place of the hydrazone compound in the formation of CTL in Example 1. This will be referred to as "comparative sample 1."

Comparative Example 2 A comparative electrophotographic photoreceptor was produced in the same manner as in Example 1, except that an oxadiazole derivative having the following structural formula was used in place of the hydrazone compound in the formation of CTL in Example 1. This will be referred to as "comparative sample 2."

The electrophotographic photoreceptors obtained as described above, Samples 1 to 10, Comparative Sample 1, and Comparative Sample 2 were each electrophotographed using an "electrometer SP-428 model" (manufactured by Kawaguchi Electric Seisakusho). We investigated the characteristics. That is, the acceptance potential VA (V) when the surface of the photoreceptor is charged with a charging voltage of -6 KV for 5 seconds, and the potential V (V) after dark decay for 5 seconds.
Exposure amount E required to attenuate the desired potential by 1/2
1/2 (lux seconds), historically low yield rate (VA-νI)/
VAX100 (%) was investigated.

The results are shown in Table 1.

From the results shown in Table 1, 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 attached to a dry electronic copying machine "U-B! Black paper potential Vb (V) and white paper potential V at 0
w(V) to "electrostatic voltmeter 14"
4D-ID type" (manufactured by Monroe Electronics Inc.), and was measured just before the phenomenon occurred. The results are shown in Table 2.

The black paper potential here refers to the surface potential of the photoreceptor when the above-mentioned copying cycle is performed using black paper with a reflection density of 1.3 as the original, and the white paper potential refers to the surface potential of the photoreceptor when the original is a black paper with a reflection density of 1.3. Represents the surface potential of the body.

(However, in the table, ΔVb (V) and ΔVw (V) indicate the amount of variation in the black paper potential Vb (V) and white paper potential Vn (V), respectively, and the variation amount c) + indicates an increase and - indicates a decrease. ) As is clear from the results in Table 2, the electrophotographic photoreceptor of the present invention maintains the potential history state stably even when subjected to the reverse aperture electrophotographic process, and can produce images with good image quality. It can be stably formed in large numbers.

[Brief explanation of drawings]

FIG. 1 is an explanatory sectional view showing an example of the structure of the electrophotographic photoreceptor of the present invention, FIG. 2 is an explanatory sectional view showing another example of the structure of the electrophotographic photoreceptor of the invention, and FIGS. 3 and 4 2A and 2B are explanatory cross-sectional views showing still other structural examples of the electrophotographic photoreceptor of the present invention. 1... Conductive support 2... Carrier generation layer (CGL) 3... Carrier transport layer (CTL) 4... Photosensitive layer 5... Intermediate layer 1A... Insulating substrate 1B...・1 copper battery case 1 x valve v
Toshihiko Oi (So-I"i・'(:i'yama 1", 4'F (-7i type) l'
1'il:il53'14'12311special1・'l'1
5'J% blind young imimo Kazuo) 1 No. 1 jl', f', ')
, 'j,';), II/lII57:1 Special Edition 1111 No. 208517' Bow 2 Famous aspect of the invention, However, the true photoconductor 3 jlli18 Go z, Irises f'LI- ri) Bar (1, ↑H1'tL!li;j'
i person - 2-26 Nishi-Shinjuku, Shinjuku-ku, Tokyo
No. ill1i 1 (4f・(佳1・)(127) Konishi Roku Photography Ririn Shiki Company 4, Agent No. rihlii [Instruction 1t)l:lfi Stomach''March 29, 1958-Sun-'2)I ￥ 1 page all ["J"'゛--" 2) Drawing page 1'S (changed to 1"'l hiro) J-Continuation 11i-IE;"?, <spontaneous) Showa 5!, i:::i bow!, I no 2! l11 special, 1' 11 ko, Shiraotshu Kazuto 11 1 thing i'l'l) Display 1981 holding ii'l'l? J1'nee n/! f-th t,
'il'7-j2, the name of Ueko Ming,? Lil'J' 14, photoconductor 3, correction 4-relationship with right thing Ino 1 41ii'F:, IiIi'j person ii
Location: Shinjuku, Tokyo, Nishishin? ? ill old 4G'jlF2; Name (12″l) Konishi Roku'3J'f,,-1-',:'l
'Share, In) 4. Daikeito's name (7815) Patent attorney - 1 person it', l', i9' Ichizumepo 124-20, II 5. Subject of amendment jjl item + revision of old invention 11Z,; rl' (, light grip 64 correction content 1) light IIIili th j5; mouth"1 ratio II example 141
Exploration E + Jru fM Zohachi 1. Record. I,・Uoto:Xnl-
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Claims (1)

[Scope of Claims] 1) An electrophotographic photoreceptor in which a photosensitive layer comprising a combination of a carrier generation phase and a carrier transport phase is provided on a conductive support, wherein the carrier generation phase is represented by the following general formula Ll). 1. An electrophotographic photoreceptor, characterized in that the carrier transport phase contains a hydrazone compound represented by the following general formula [■]. General formula (1) (wherein, Ar1, Ar2 and Ar3: substituted and unsubstituted carbocyclic aromatic ring groups, respectively, R1: electron-withdrawing group, X: hydroxy group, where R and R are each a hydrogen atom , a substituted or unsubstituted alkyl group, R5 is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl 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 may be used.) Z: Substituted or unsubstituted carbocyclic aromatic group Atom groups necessary to constitute a group ring or a substituted or unsubstituted heterocyclic aromatic ring, R2: hydrogen atom, substituted or unsubstituted amino 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.] [In the formula, R8: a methyl group, an ethyl group, a 2-hydroxyethyl group, or a 2- Chlorethyl group, R7: represents a methyl group, ethyl group, benzyl group or phenyl group.]