JPH04235964A - Bisazo compound - Google Patents

Abstract

PURPOSE:To obtain a new bisazo compound useful as an organic photoconductor and as a charge-producing pigment in electrophotographic photosensitive units practically usable as high-speed copiers, etc. CONSTITUTION:A compound expressed by formula I (A is H, Cl, NO2, CH3, etc.). The aforementioned compound is obtained by reacting a diazonium salt compound expressed by formula II (X is anionic functional group) with a compound expressed by formula III, then reacting the resultant compound with a compound expressed by formula IV or reacting the compound expressed by formula II with the compound expressed by formula IV and subsequently reacting the prepared compound with the compound expressed by formula III. The reaction is carried out by a method for dissolving the compound expressed by formula III or IV in an organic solvent such as DMSO, adding the compound expressed by formula II thereto and then adding either of the compounds expressed by formulas III and IV in the second stage, etc.

Description

[Detailed description of the invention]

0001

FIELD OF THE INVENTION This invention relates to bisazo compounds, and more particularly to bisazo compounds useful as organic photoconductors.

0002

[Prior Art] It has been known that certain azo compounds are effective as charge-generating pigments used in charge-generating layers of laminated photoreceptors, which are one form of electrophotographic photoreceptors. There is. The laminated photoreceptor referred to herein means that a charge-generating pigment having the ability to generate charge carriers by light is applied onto a conductive support by an appropriate method such as vacuum evaporation, coating with a pigment solution, or adding a pigment to a resin solution. Charge transport is a method in which charge carriers generated in the charge generation layer can be efficiently injected onto the charge generation layer by coating a dispersion liquid containing fine particles dispersed therein, and the charge carriers generated in the charge generation layer can be efficiently transferred. It is a photoreceptor on which a charge transporting layer is formed (usually the charge transporting layer is composed of a charge transporting substance and a binder resin). Conventionally,
Examples of azo compounds used in this type of photoreceptor include JP-A No. 47-37543 and JP-A No. 52-Sho.
Known compounds include benzidine-based bisazo compounds described in Japanese Patent Publication No. 55643, and stilbene-based bisazo compounds described in JP-A-52-8832. However, conventional laminated photoreceptors using azo compounds generally have low sensitivity and are therefore unsatisfactory as photoreceptors for high-speed copying machines.

0003

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

0004

[Means for Solving the Problems] According to the present invention, a bisazo compound represented by the above formula [Formula 1] is provided. This bisazo compound can be produced as follows. That is, a diazonium salt compound represented by the following [Chemical formula 4],

embedded image [In the formula, X represents an anionic functional group. ] The following formula [Chemical formula 5]
or a compound represented by [Chemical formula 6]

[Formula A is H, Cl, NO2, CH3, C2 H5
or OCH3]

[C6]

[0005] When the compound represented by formula [Chemical formula 5] is reacted first, the compound represented by formula [Chemical formula 6] is reacted first, and the compound represented by formula [Chemical formula ] When reacting a compound represented by the formula [Chemical formula 5
] A bisazo compound represented by the formula [Formula 1] can be produced by reacting a compound represented by the formula [Formula 1]. Alternatively, the bisazo compound of the formula [Chemical formula 1] can also be produced by reacting a diazonium salt compound represented by the general formula [Chemical formula 7] with a compound represented by the formula [Chemical formula 6]. .

[C7]

[In the formula, X represents an anionic functional group] Furthermore, the bisazo compound of the present invention can also be produced by the following method. That is, the following general formula [Chemical formula 8
] A diazonium salt compound represented by

[Formula 8] This is a method by reacting a compound represented by the above formula [Formula 5] [wherein X represents an anionic functional group]. X in the above [Chemical formula 4], [Chemical formula 7], and [Chemical formula 8] represents an anionic functional group, such as BF4, perchlorate, iodite, chloride, bromide, sulfate, hexafluorophosphate. -to, hexafluoroantimonate, periodate, P-toluenesulfonate and the like are preferred.

Among the bisazo compounds [formula 1] of the present invention, particularly preferred compounds include, for example, the following compounds.

[Chemical formula 9]

[Chemical formula 10]

[Chemical formula 11]

[Chemical formula 12]

Alternatively, [Chemical formula 2] shown in claims 2 and 3,
[Chemical formula 3] etc. can be mentioned. Formula of the present invention [Chemical formula 1]
As described above, the bisazo compound represented by It is useful as a charge generating material in an electrophotographic photoreceptor having a layer, and as a photoconductive material in an electrophotographic photoreceptor having a photosensitive layer in which a photoconductive substance is dispersed in a resin. As mentioned above, the bisazo compound represented by the formula [Chemical formula 1] of the present invention is a diazonium salt compound represented by the general formula [Chemical formula 4] and the coupler represented by the formula [Chemical formula 5] or [Chemical formula 6]. - by sequentially reacting them in two steps, or by isolating the diazonium salt compound of the general formula [Chemical formula 7] or [Chemical formula 8] obtained by the first coupling reaction, and then further reacting the corresponding couplers -. It can be obtained by letting In practice, this reaction is performed using N,N-dimethylformamide (D
MF) or dimethyl sulfoxide (DMSO), the formula used in the first step coupling reaction [Chemical formula 5
] or [Chemical formula 6] is dissolved, and a diazonium salt compound represented by the general formula [Chemical formula 4] is added thereto, and if necessary, a base such as an aqueous sodium acetate solution or an organic amine is added. The first stage coupling reaction is terminated by adding the sexual substance. The reaction temperature at this time is preferably about -20°C to about 40°C.

In the second stage coupling reaction, a coupler of formula [Chemical formula 5] or [Chemical formula 6] which is different from the coupler used in the first stage coupling reaction is added to the reaction mixture obtained above. - is further added to the coupling reaction mixture of the first stage, and if necessary, it is completed by adding a basic substance such as an aqueous sodium acetate solution or an organic amine, or the coupling reaction mixture of the first stage is If necessary, add water or an acidic aqueous solution such as dilute hydrochloric acid (at this time, perform sufficient cooling so as not to decompose the diazonium salt compound of the general formula [Chemical formula 7] or [Chemical formula 8] produced by the reaction. The diazonium salt compound of the general formula [Chemical formula 7] or [Chemical formula 8] is separated by filtration, and the diazonium salt compound and the diazonium salt compound are further separated. , 1st
The reaction is completed by reacting a coupler of formula [Chemical formula 5] or [Chemical formula 6] different from the coupler used in the coupling reaction of the first stage in the same manner as the coupling reaction of the first stage. In the reaction mixture obtained by any method, after the completion of the reaction, the precipitated crystals are collected by filtration and purified by an appropriate method (for example, washing with water or/and an organic solvent, recrystallization method, etc.). The production of the bisazo compound of [Chemical formula 1] is completed.

0010

[Example] In order to demonstrate that the bisazo compound of the present invention can be easily produced as described above and is an effective material for electrophotographic photoreceptors, Examples and Application Examples are given below. However, the present invention is not limited to this. Example 1 2-Hydroxy-3-(2-methylphenyl)carbamoyl-11H-benzo[a]carbazole [Chemical formula 6]0.
92 g (2.5 mmol) was dissolved in 100 ml of DMF at room temperature to obtain 9-fluorenone-2,7-bisdiazonium bistetrafluoroborate (formula [Chemical formula 4]
) 1.02 g (2.5 mmol) was added. After stirring at room temperature for 10 minutes, 0.88 g (2.5 mmol) of 2-hydroxy-3-phenylcarbamoyl-11H-benzo[a]carbazole (formula [Chemical formula 5] A:H) was added to DM.
Add the solution dissolved in 100ml of F, then 10.5%
8 ml of aqueous sodium acetate solution was added and stirred at room temperature for 2 hours. The formed precipitate was filtered off, and DM was heated to 80°C.
It was washed three times with 200 ml of F and then twice with 200 ml of water. After drying at 120° C. under reduced pressure, the formula [Chemical formula 9]
A bisazo compound was obtained. Yield 53%, melting point 280°C or higher, infrared absorption spectrum (KBr tablet method) [Figure 1]
It was shown to.

Example 2 The reaction temperature, which was carried out at room temperature in Example 1, was changed from 10 to 1.
Production was carried out in exactly the same manner as in Example 1 except that the temperature was 5°C, to obtain a bisazo compound of the formula [Chemical formula 9]. Example 3 A bisazo compound of formula [Chemical formula 9] was produced in the same manner as in Example 1 except that the reaction temperature was changed from room temperature in Example 1 to 0 to 5°C. Ta. Example 4 In Example 1, the coupler of formula [Chemical formula 6] was first reacted, and then the coupler of formula [Chemical formula 5] was reacted. After the reaction, production was carried out in exactly the same manner as in Example 1 except that the coupler of the formula [Chemical formula 6] was then reacted to obtain a bisazo compound of the formula [Chemical formula 9].

Application Example 1 76 parts by weight of the bisazo compound of formula [Chemical formula 9], 1260 parts by weight of a tetrahydrofuran solution (solid content concentration 2%) of polyester resin (Pylon 200 manufactured by Toyobo Co., Ltd.), and 3700 parts by weight of tetrahydrofuran were deposited by aluminum vapor deposition. It was applied onto the aluminum surface of the polyester base (conductive support) using a doctor blade, dried naturally,
A charge generation layer having a thickness of about 1 μm was formed. In addition to this charge generation, 2 parts by weight of 4'-N,N-diphenylamino-α-phenylstilbene and polycarbonate were added as a charge transport substance.
A solution prepared by mixing and dissolving 2 parts by weight of resin (Teijin Panlite K-1300) and 16 parts by weight of tetrahydrofuran was applied using a doctor blade, and dried at 80°C for 2 minutes and then at 105°C for 5 minutes. A charge transport layer having a thickness of about 20 μm was formed using the above steps to prepare a laminated photoreceptor. The laminated photoconductor produced as described above was negatively charged by -6 KV corona discharge for 20 seconds using an electrostatic copying paper tester (Kawaguchi Electric Seisakusho, Model SP428). Leave it in the dark for 20 seconds, then check the surface potential V
Measure po (V), then irradiate the surface with light using a tungsten lamp so that the illumination intensity is 4.5 lux, and calculate the time until Vpo becomes 1/2 due to light attenuation (
second), and calculate the half-decreased exposure amount E1/2 (seconds) as the sensitivity of the photoreceptor.
lux seconds) was calculated. The photoreceptor according to the present invention has a Vpo of -668V and an E1/2 of 1.5 lux·sec, indicating that it is a highly sensitive photoreceptor.

Example 5 2-Hydroxy-3-(2-methylphenyl)carbamoyl-11H benzo[a]carbazole [Formula 6] 0.9
2 g (2.5 mmol) was dissolved in 100 ml of DMF,
9-fluorenone-2,7-bisdiazonium bistetrafluoroborate ([Chemical formula 4], X:BF4
) 1.02 g (2.5 mmol) was added. 1 at room temperature
After stirring for 0 minutes, 0.97 g (2
．． A solution of 5 mmol) dissolved in 100 ml of DMF was added, followed by 8 ml of a 10.5% aqueous sodium acetate solution, and the mixture was stirred for 2 hours at room temperature. Filter out the formed precipitate,
It was washed three times with 200 ml of DMF heated to 80°C and then twice with 200 ml of water. The mixture was dried at 120° C. under reduced pressure to obtain a bisazo compound of the formula [Chemical formula 10]. Yield 59%, melting point 280℃ or higher, infrared absorption spectrum (K
Br tablet method) is shown in [Figure 2].

Example 6 The reaction temperature, which was carried out at room temperature in Example 5, was changed from 10 to 15
A bisazo compound of the formula [Chemical formula 10] was obtained by carrying out the production in exactly the same manner as in Example 5, except that the temperature was 0.degree. Example 7 The reaction temperature performed at room temperature in Example 5 was changed from 0 to 5.
Production was carried out in exactly the same manner as in Example 5 except that the temperature was changed to obtain a bisazo compound of the formula [Chemical formula 10]. Example 8 In Example 5, the coupler of formula [Chemical formula 6] was first reacted, and then the coupler of formula [Chemical formula 5] was reacted, and then the coupler of formula [Chemical formula 5] was reacted first. After the reaction, production was carried out in exactly the same manner as in Example 5 except that the coupler of formula [Chemical formula 6] was then reacted to obtain a bisazo compound of formula [Chemical formula 10]. Application example 2 In application example 1, instead of the bisazo compound of [Chemical formula 9], [
A photoreceptor was prepared in the same manner as in Application Example 1 except that the bisazo compound of Chemical Formula 10 was used. When the characteristics of this photoreceptor were measured in the same manner as in Application Example 1, the Vpo was -51
8V, E1/2 is 0.7 lux·sec, and it is understood that it is a highly sensitive photoreceptor.

Example 9 2-Hydroxy-3-(2-methylphenyl)carbamoyl-11H benzo[a]carbazole [Formula 6] 0.9
2 g (2.5 mmol) was dissolved in 100 ml of DMF,
9-fluorenone-2,7-bisdiazonium bistetrafluoroborate (formula [Chemical formula 4]X: BF4) at room temperature
) 1.02 g (2.5 mmol) was added. 1 at room temperature
After stirring for 0 minutes, 0.99 g (2.5 mmol) of 2-hydroxy-3-(4-nitrophenyl)carbamoyl-11H-benzo[a]carbazole was added to DMF100.
ml of the solution, then add 10.5% acetic acid solution.
8 ml of Da aqueous solution was added and stirred at room temperature for 2 hours. The formed precipitate was filtered out and DMF200 heated to 80°C.
ml and then twice with 200 ml of water. The mixture was dried at 120° C. under reduced pressure to obtain a bisazo compound of the formula [Formula 12]. The yield was 56%, the melting point was 280°C or higher, and the infrared absorption spectrum (KBr tablet method) was shown in [Figure 3].

Example 10 The reaction temperature in Example 9, which was carried out at room temperature, was changed from 10 to 15
A bisazo compound of the formula [Chemical formula 12] was obtained by carrying out the production in exactly the same manner as in Example 9, except that the temperature was 0.degree. Example 11 A bisazo compound of formula [Chemical formula 12] was produced in exactly the same manner as in Example 9, except that the reaction temperature was changed from 0 to 5°C instead of the room temperature in Example 9. . Example 12 In Example 9, the coupler of formula [Chemical formula 6] was first reacted, and then the coupler of formula [Chemical formula 5] was reacted, and then the coupler of Formula [Chemical formula 5] was reacted first. Example 9 except that the coupler of the formula [Chemical formula 6] was then reacted.
The production was carried out in exactly the same manner as above to obtain a bisazo compound of the formula [Chemical formula 12]. Application example 3 In application example 1, instead of the bisazo compound of [Chemical formula 9], [
A photoreceptor was prepared in the same manner as in Application Example 1 except that the bisazo compound of Chemical Formula 12] was used. When the characteristics of this photoreceptor were measured in the same manner as in Application Example 1, the Vpo was -51
6V and E1/2 are 0.7 lux·sec, which indicates that it is a highly sensitive photoreceptor.

Example 13 2-Hydroxy-3-(2-methylphenyl)carbamoyl-11H-benzo[a]carbazole [Formula 6]0.
92 g (2.5 mmol) was dissolved in 100 ml of DMF, and 9-fluorenone-2,7-bisdiazonium, bistetrafluoroborate (formula [Chemical formula 4], X:B
1.02 g (2.5 mmol) of F4) was added. After stirring at room temperature for 10 minutes, 2-hydroxy-3-(4
-methylphenyl)carbamoyl-11H-benzo[a
] Carbazole (formula [chemical formula 5], A: methyl at position 4) 0.
A solution of 92 g (2.5 mmol) dissolved in 100 ml of DMF was added, and then 10.5% aqueous sodium acetate solution was added.
ml was added and stirred at room temperature for 2 hours. The formed precipitate was filtered off and washed three times with 200 ml of DMF heated to 80°C, and then twice with 200 ml of water. It was dried at 120° C. under reduced pressure to obtain a bisazo compound of the formula [Formula 11]. The yield was 55%, the melting point was 280°C or higher, and the infrared absorption spectrum (KBr tablet method) was shown in [Figure 4].

Example 14 The reaction temperature performed at room temperature in Example 13 was changed from 10 to 1.
Production was carried out in exactly the same manner as in Example 13, except that the temperature was 5°C, to obtain a bisazo compound of the formula [Chemical formula 11]. Example 15 The reaction temperature performed at room temperature in Example 13 was changed from 0 to 5°C.
Production was carried out in exactly the same manner as in Example 13, except for the steps in Example 13, to obtain a bisazo compound of formula [Chemical formula 11]. Example 16 In Example 13, the coupler of formula [Chemical formula 6] was first reacted, and then the coupler of formula [Chemical formula 5] was reacted. After reacting,
Next, production was carried out in exactly the same manner as in Example 13 except that the coupler of formula [Chemical formula 6] was reacted, to obtain a bisazo compound of formula [Chemical formula 11].

Application Example 4 76 parts by weight of the bisazo compound of formula [Chemical formula 11], 1260 parts by weight of a tetrahydrofuran solution (solid content concentration 2%) of polyester resin (Vylon 200 manufactured by Toyobo Co., Ltd.), and 3700 parts by weight of tetrahydrofuran were deposited by aluminum evaporation. The mixture was coated onto the aluminum surface of the polyester base (conductive support) using a doctor blade and air-dried to form a charge generation layer with a thickness of about 1 μm. On this charge generation layer, 3-formyl-9-ethylcarbazole-1-methyl-1-phenylhydrazone 2 was added as a charge transport substance.
Parts by weight, polycarbonate resin (Teijin Panlite K)
-1300) and 16 parts by weight of tetrahydrofuran were applied using a doctor blade and dried at 80°C for 2 minutes and then at 105°C for 5 minutes to create a charge transport layer with a thickness of approximately 20 μm. A laminated photoreceptor was created by forming layers. Regarding the laminated photoconductor produced as described above, an electrostatic copying paper testing device (manufactured by Kawaguchi Electric Seisakusho Co., Ltd.) was used.
SP428 type) was used to generate -6KV corona discharge for 20
After charging it negatively for 20 seconds, it was left in a dark place for 20 seconds, the surface potential Vpo (V) at that time was measured, and then the surface was irradiated with light using a tungsten lamp at an illuminance of 4.5 lux. , Vpo becomes 1 due to optical attenuation.
/2 was determined, and the half-reduced exposure amount E1/2 (lux/second) was calculated as the sensitivity of the photoreceptor. The Vpo of the photoreceptor related to the present invention is -1110V, E1/
2 is 1.1 lux·sec, which indicates that it is a highly sensitive photoreceptor.

Example 17 2-Hydroxy-3-(2-methylphenyl)carbamoyl-11H-benzo[a]carbazole [Formula 6]0.
92 g (2.5 mmol) was dissolved in 100 ml of DMF, and 9-fluorenone-2,7-bisdiazonium bistetrafluoroborate ([Chemical formula 4], X:BF4
) 1.02 g (2.5 mmol) was added. After stirring at room temperature for 10 minutes, 2-hydroxy-3-(3-methoxyphenyl)carbamoyl-11H benzo[a]carbazole (formula [Chemical formula 5] A: methoxy at the 3-position) 0.96
A solution of g (2.5 mmol) dissolved in 100 ml of DMF was added thereto, followed by 8 ml of a 10.5% aqueous sodium acetate solution, and the mixture was stirred at room temperature for 2 hours. The formed precipitate was filtered off and washed three times with 200 ml of DMF heated to 80°C, and then twice with 200 ml of water. It was dried at 120° C. under reduced pressure to obtain the bisazo compound of the formula [Chemical formula 2]. The yield was 54%, the melting point was 280°C or higher, and the infrared absorption spectrum (KBr tablet method) was shown in [Figure 5].

Example 18 The reaction temperature performed at room temperature in Example 17 was changed from 10 to 1.
Production was carried out in exactly the same manner as in Example 17, except that the temperature was 5°C, to obtain a bisazo compound of formula [Chemical formula 2]. Example 19 The reaction temperature performed at room temperature in Example 17 was changed from 0 to 5°C.
A bisazo compound of formula [Chemical formula 2] was obtained by carrying out the production in exactly the same manner as in Example 17, except for the following steps. Example 20 In Example 17, the coupler of formula [Chemical formula 6] was first reacted, and then the coupler of formula [Chemical formula 5] was reacted, and then the coupler of Formula [Chemical formula 5] was reacted first. After that, production was carried out in exactly the same manner as in Example 17 except that the coupler of the formula [Chemical formula 6] was then reacted to obtain a bisazo compound of the formula [Chemical formula 2]. Application example 5 In application example 1, instead of the bisazo compound of [Chemical formula 9], [
A photoreceptor was prepared in the same manner as in Application Example 1 except that the bisazo compound of Chemical Formula 2] was used. Application example 1 for this photoreceptor
When the characteristics were measured in the same manner as above, Vpo was -432
V and E1/2 are 1.7 lux·sec, which indicates that the photoreceptor is highly sensitive.

Example 21 2-Hydroxy-3-(2-methylphenyl)carbamoyl-11H-benzo[a]carbazole [Formula 6]0.
92 g (2.5 mmol) was dissolved in 100 ml of DMF, and 9-fluorenone-2,7-bisdiazonium bistetrafluoroborate (formula [Chemical formula 4], X: BF
4) Added 1.02 g (2.5 mmol). After stirring at room temperature for 10 minutes, 2-hydroxy-3-(2-ethylphenyl)carbamoyl-11H- (formula [Chemical formula 5]A
:2-position ethyl)benzo[a]carbazole 0.95g
(2.5 mmol) dissolved in 100 ml of DMF was added, followed by 8 ml of a 10.5% aqueous sodium acetate solution, and the mixture was stirred for 2 hours at room temperature. The formed precipitate was filtered and washed three times with 200 ml of DMF heated to 80°C.
Next, it was washed twice with 200 ml of water. It was dried at 120° C. under reduced pressure to obtain a bisazo compound of the formula [Chemical formula 3]. Yield 66%, melting point 280℃ or higher, infrared absorption spectrum (
KBr tablet method) is shown in [Figure 6].

Example 22 The reaction temperature performed at room temperature in Example 21 was changed from 10 to 1.
Production was carried out in exactly the same manner as in Example 21, except that the temperature was 5°C, to obtain a bisazo compound of the formula [Chemical formula 3]. Example 23 The reaction temperature performed at room temperature in Example 21 was changed from 0 to 5°C.
The production was carried out in exactly the same manner as in Example 21, except for the following steps, to obtain a bisazo compound of the formula [Chemical formula 3]. Example 24 In Example 21, the coupler of formula [Chemical formula 6] was reacted first, and then the coupler of formula [5] was reacted, and the coupler of formula [Chemical formula 5] was reacted first. After that, production was carried out in exactly the same manner as in Example 21 except that the coupler of formula [Chemical formula 6] was then reacted to obtain a bisazo compound of formula [Chemical formula 3]. Application example 6 In application example 1, instead of the bisazo compound of [Chemical formula 9], [
A photoreceptor was prepared in the same manner as in Application Example 1 except that the bisazo compound of Chemical Formula 3 was used. Application example 1 for this photoreceptor
A photoreceptor was prepared in the same manner as described above. When the characteristics of this photoreceptor were measured in the same manner as in Application Example 1, the Vpo was -
1074V, E1/2 is 1.3 lux·sec, and it is understood that it is a highly sensitive photoreceptor.

[0024]

As explained above, the bisazo compound of the present invention can be easily produced, and as is clear from the application examples, it can be used as a highly sensitive electrophotographic photoreceptor that is practical for use in high-speed copying machines, etc. It is particularly used as a charge-generating pigment in laminated photoreceptors.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an infrared absorption spectrum of the compound of the present invention obtained in Example 1.

FIG. 2 is the same diagram obtained in Example 5.

FIG. 3 is the same diagram obtained in Example 9.

FIG. 4 is the same diagram obtained in Example 13.

FIG. 5 is the same diagram obtained in Example 17.

FIG. 6 is the same diagram obtained in Example 21.

Claims (3)

[Claims] [Claim 1] A bisazo compound represented by the following formula [Formula 1]. [Formula, A represents H, Cl, NO2, CH3, C2H5 or OCH3] [Claim 2] A bisazo compound represented by the following formula [Chemical formula 2]. [Case 2] 3. A bisazo compound represented by the following formula [Claim 3]. [Chemical formula 3]