JP3096074B2 - Bisazo compounds - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bisazo compound, and more particularly to a bisazo compound useful as an organic photoconductor.

[0002]

2. Description of the Related Art It has been known that a certain azo compound is effective as a charge generating pigment used in a charge generating layer of a laminated photoreceptor which is one form of an electrophotographic photoreceptor. I have. The term "laminated photoreceptor" as used herein means that a charge-generating pigment having the ability to generate charge carriers by light is applied to a conductive support by a suitable method, for example, vacuum evaporation, application of a pigment solution, or application of a pigment to a resin solution. The charge generation layer is formed as a thin layer by applying a dispersion liquid in which fine particles are dispersed, and the charge carriers generated in the charge generation layer can be efficiently injected onto the charge generation layer. The photoreceptor has a layer (usually, the charge transport layer is composed of a charge transport substance and a binder resin). Conventionally,
Examples of the azo compound used for this type of photoreceptor include, for example, JP-A-47-37543 and JP-A-52-75543.
There are known benzidine-based bisazo compounds described in JP-A-55643 and the like and stilbene-based bisazo compounds described in JP-A-52-8832. However, a conventional laminated photoreceptor using an azo compound generally has low sensitivity, and is therefore insufficient as a photoreceptor for a high-speed copying machine.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a bisazo compound useful in an electrophotographic photoreceptor, particularly useful in the above-mentioned laminated photoreceptor.

[0004]

According to the present invention, there is provided a bisazo compound represented by the above formula (1). This bisazo compound can be produced as follows. That is, a diazonium salt compound represented by the following formula (2):

[0005]

Embedded image [Wherein X represents an anionic functional group. ] A compound represented by the following formula (3) or (4)

[0006]

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[0007]

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[Wherein R represents a methyl group. Is reacted first, then the compound represented by the formula (3) is reacted first, the compound represented by the formula (4) is reacted, and the compound represented by the formula (4) is first reacted. Is reacted with the compound represented by the formula (3) to produce the bisazo compound represented by the formula (1). Alternatively, a diazonium salt compound represented by the general formula (5)
A bisazo compound of the formula (1) can also be produced by reacting with a compound represented by the formula:

[0009]

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[Wherein X represents an anionic functional group] Further, the bisazo compound of the present invention can also be produced by the following method. That is, the following general formula (6)
A diazonium salt compound represented by

[0011]

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[Wherein R represents a methyl group and X represents an anionic functional group] This is a method by reacting with a compound represented by the above formula (3). X in the above (2), (5) and (6) represents an anionic functional group, for example, BF ₄ , perchlorate, iodide, chloride,
Bromide, sulfate, hexafluorophosphate, hexafluoroantimonate, periodate,
P-toluenesulfonate and the like are preferred. The bisazo compound of the present invention is represented by the following formula (7).

[0013]

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As described above, the bisazo compound represented by the formula (1) of the present invention is useful as a charge generating material for a laminated electrophotographic photoreceptor. as a charge generating material in an electrophotographic photosensitive member having a photosensitive layer of single layer type in which is dispersed the door, and as photoconductive substances in electrophotographic photoreceptor having a photosensitive layer formed by dispersing a photoconductive material in a resin Is also useful.

As described above, the bisazo compound represented by the formula (1) of the present invention comprises a diazonium salt compound represented by the general formula (2) and a coupler represented by the formula (3) or (4). Can be sequentially reacted in two steps, or by isolating the diazonium salt compound of the formula (5) or (6) obtained by the first coupling reaction, and further reacting the corresponding coupler. .

In practice, this reaction is carried out using N, N-dimethylformamide (DMF) or dimethylsulfoxide (DMF).
The coupler represented by the formula (3) or (4) used in the first-stage coupling reaction is dissolved in an organic solvent such as SO), and the diazonium salt compound represented by the general formula (2) is dissolved therein. The first-stage coupling reaction is completed by adding and, if necessary, adding a basic substance such as an aqueous solution of sodium acetate or an organic amine. The reaction temperature at this time is about -20 ° C to about 4 ° C.
0 ° C. is preferred.

In the second stage coupling reaction, a coupler of the formula (3) or (4) different from the coupler used in the first stage coupling reaction is further added to the reaction mixture obtained above. If necessary, as in the case of the first-stage coupling reaction, the reaction can be completed by adding a basic substance such as an aqueous solution of sodium acetate or an organic amine, or the first-stage coupling reaction mixture can be prepared as follows.
If necessary, add water or an acidic aqueous solution such as dilute hydrochloric acid (in this case, it is necessary to perform sufficient cooling so as not to decompose the diazonium salt compound of the general formula (5) or (6) generated by the reaction. There is preferably
Desirably, the treatment is performed at 10 ° C. or less. The diazonium salt compound of the general formula (5) or (6) is isolated by filtration, and this diazonium salt compound is different from the coupler (3) or (3) which is different from the coupler used in the first-stage coupling reaction. The reaction is completed by reacting the coupler of 4) in the same manner as in the first stage coupling reaction. In any reaction mixture obtained by any of the methods, after the reaction is completed, the precipitated crystals are collected by filtration and purified by an appropriate method (for example, washing with water or / and an organic solvent, a recrystallization method, etc.), The production of the bisazo compound (1) is completed.

[0018]

EXAMPLES The bisazo compound of the present invention can be easily produced as described above, and the following examples and application examples will be described in order to clarify that it is an effective material for an electrophotographic photoreceptor. Although shown, the present invention is not limited to this.

EXAMPLE 1 0.92 g (2.5 mmol) of 2-hydroxy-3- (2-methylphenyl) carbamoyl-11H-benzo [a] carbazole [R is a methyl group in the formula (4)] was added to 100 ml of DMF. After dissolution, 1.02 g (2.5 mmol) of 9-fluorenone-2,7-bisdiazonium bistetrafluoroborate (Formula (2) X: BF ₄ ) was added at room temperature. After stirring at room temperature for 10 minutes, a solution of 0.74 g (2.5 mmol) of 2-hydroxy-3- (2-chlorophenyl) carbamoylnaphthalene [formula (3)] in 100 ml of DMF was added.
8 ml of a 5% aqueous sodium acetate solution was added, and the mixture was stirred at room temperature for 2 hours. The precipitate formed is filtered off, washed three times with 200 ml of DMF heated to 80 ° C. and then washed twice with 200 ml of water.
Washed twice. Drying at 120 ° C. under reduced pressure gave the bisazo compound of the above formula (7). Yield 58%, melting point 28
At 0 ° C. or higher, the infrared absorption spectrum (KBr tablet method) is shown in FIG.

Elemental analysis values

Example 2 The reaction temperature at room temperature in Example 1 was 10 to 1
The production was carried out in exactly the same manner as in Example 1 except that the reaction was carried out at 5 ° C. to obtain a bisazo compound of the formula (7).

Example 3 A bisazo compound of the formula (7) was prepared in exactly the same manner as in Example 1 except that the reaction was carried out at room temperature in the range of 0 to 5 ° C. I got

Example 4 In Example 1, in Formula (4), a coupler in which R is a methyl group was reacted first, and then a coupler of Formula (3) was reacted. After the reaction of the coupler, the production was carried out in exactly the same manner as in Example 1 except that the coupler of formula (4) in which R was a methyl group was reacted to obtain a bisazo compound of formula (7).

Application Example 1 76 parts by weight of the bisazo compound of the formula (7), 1,260 parts by weight of a polyester resin (Pylon 200 manufactured by Toyobo Co., Ltd.) in tetrahydrofuran (solid content: 2%), and 3,700 parts by weight of tetrahydrofuran were aluminum-deposited. The resultant was applied on an aluminum surface of a polyester base (conductive support) using a doctor blade and air-dried to form a charge generating layer having a thickness of about 1 μm.

On this charge generation layer, 2 parts by weight of 4'-N, N-diphenylamino-α-phenylstilbene, 2 parts by weight of a polycarbonate resin (Panlite K-1300 manufactured by Teijin Limited) and tetrahydrofuran 1
A solution obtained by mixing and dissolving 6 parts by weight is applied using a doctor blade, and dried at 80 ° C. for 2 minutes, and then at 105 ° C. for 5 minutes to form a charge transport layer having a thickness of about 20 μm. Created.

With respect to the laminated photoreceptor prepared as described above, an electrostatic copying paper tester (Kawaguchi Denki Seisakusho, S
Using a P428 type), a −6 KV corona discharge was performed for 20 seconds to make the surface negatively charged. After that, the surface was left in a dark place for 20 seconds, and the surface potential Vpo (V) at that time was measured. Is irradiated so that the illuminance becomes 4.5 lux, and Vpo becomes 1 by light attenuation.
The half-exposure amount E1 / 2 (lux · second) was calculated as the sensitivity of the photoreceptor by calculating the time (second) until the value became 1/2.

Vpo of the photosensitive member according to the present invention is -72.
6V and E1 / 2 are 0.7 lux / sec, which indicates that the photosensitive member has high sensitivity.

[0028]

As described above, the bisazo compound of the present invention can be easily produced, and as is apparent from the application examples, a high-sensitivity electrophotographic photoreceptor practical for high-speed copying machines and the like, In particular, it is used as a charge generating pigment in a laminated photoreceptor.

[Brief description of the drawings]

FIG. 1 shows an infrared absorption spectrum of the compound of the present invention obtained in Example 1.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) C09B 35/233 C09B 35/037 C09B 35/033 C09B 35/039 C09B 35/021 G03G 5/06 347

Claims (4)

(57) [Claims] 1. A bisazo compound represented by the following formula (1). Embedded image [Wherein, R represents a methyl group] 2. A charge generation layer and a charge transfer layer on a conductive support.
In a laminated electrophotographic photosensitive member having a transfer layer, the charge generation
The bisazo compound according to claim 1, wherein the charge generating substance in the green layer is
A laminated electrophotographic photosensitive member, characterized in that: 3. A charge generation material in a resin on a conductive support.
Having a single-layer type photosensitive layer in which a substance and a charge transport material are dispersed
Charge generating material in the photosensitive layer
Is the bisazo compound according to claim 1.
Single-layer electrophotographic photoreceptor. 4. A photoconductive material in a resin on a conductive support.
Photoreceptor having a photosensitive layer in which the quality is dispersed
The photoconductive material in the photosensitive layer according to claim 1, wherein
An electrophotographic photosensitive member, which is an azo compound.