JP2003307862A - Organic photoreceptor, method for forming image and image forming device and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic photoreceptor which can produce favorable images without producing image defects such as environmental memory, black spots white voids or the like and to provide a method for forming an image, an image forming device and a process cartridge by using the above organic photoreceptor. <P>SOLUTION: In the organic photoreceptor having a charge generating layer on a conducive supporting body and having a charge transfer layer deposited thereon, the charge generating substance comprises a titanyl phthalocyanine pigment showing significant diffraction peaks at 7.5° and 28.7° Bragg angles (2θ±0.2°) in the X-ray diffraction spectrum for Cu-Kα characteristic X-rays and the charge transfer layer comprises a charge transfer substance which is a mixture of stereoisomers of bis(arylethenylphenyl)aniline compounds having 40 to 90 mass% content of the maximum isomer component in the mixture. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic photoconductor used in the field of copying machines and printers, an image forming method using the organic photoconductor, an image forming apparatus, and a process cartridge.

[0002]

2. Description of the Related Art Electrophotographic photoreceptors are Se, arsenic, arsenic /
The main body has moved from an inorganic photoreceptor such as Se alloy, CdS, and ZnO to an organic photoreceptor having excellent advantages such as pollution and easiness of manufacturing, and organic photoreceptors using various materials have been developed.

In recent years, function-separated type photoconductors in which different materials are responsible for charge generation and charge transport functions have become the mainstream. Among them, a laminated organic photoconductor in which a charge generation layer and a charge transport layer are laminated. Is widely used.

In addition, focusing on the electrophotographic process, latent image forming methods are roughly classified into analog image forming using a halogen lamp as a light source and digital image forming using an LED or a laser as a light source. Recently, a digital latent image forming method is rapidly becoming the mainstream as a printer for a hard copy of a personal computer, and also in an ordinary copying machine because of the ease of image processing and the ease of development to a multi-function peripheral.

In digital image formation, a laser, particularly a semiconductor laser or an LED, is used as a light source when writing image information converted into a digital electric signal on a photoconductor as an electrostatic latent image.

The oscillation wavelengths of these laser light and LED light are near infrared light of 780 nm and 660 nm and long wavelength light close thereto. For organic photoreceptors used for digital image formation, the first requirement is high sensitivity to these long-wavelength light. It has been examined whether or not it has such characteristics. Among them, phthalocyanine pigments are relatively easy to synthesize, and many of them exhibit high sensitivity to long-wavelength light. Therefore, organic photoreceptors using phthalocyanine pigments have been widely studied and put to practical use. .

Among them, a titanyl phthalocyanine pigment having a maximum Bragg angle 2θ of 27.2 ± 0.2 ° in a powder X-ray diffraction spectrum (hereinafter, simply referred to as a Y-type titanyl phthalocyanine pigment or a Y-type) is high. It is known as a sensitive material and has been reported in academic societies (Oda et al., The Electrophotographic Society of Japan, 29 (3), 250 (1990)).

When this Y-type titanyl phthalocyanine pigment is used as a carrier generating substance, the charging characteristic and the sensitivity characteristic change due to the environment, particularly the humidity fluctuation, and the environmental memory is likely to occur. The environmental memory refers to a phenomenon in which a black belt-shaped image defect occurs in the reversal development in which the exposed portion is a toner image when the temperature and humidity greatly change. As countermeasures against the humidity fluctuation, alkylene diols, polyalkylene glycols, antistatic agents, etc. have been proposed as moisturizers in the charge generation layer of the photoreceptor (JP-A-5-313389, JP-A-5-333577, JP-A-6-118675). ). However, addition of these simple moisturizers is difficult to answer to the pursuit of higher image quality in recent years, and when added in large amounts, even moisturizers such as diol compounds tend to act as organic insulators, increasing residual potential. Defects are likely to occur. In addition, antistatic agents and the like have side effects such as reduction in charging potential.

On the other hand, in the powder X-ray diffraction spectrum, the titanyl phthalocyanine pigment (hereinafter referred to as B-type) has a remarkable peak at Bragg angle 2θ of 7.5 ° and 28.7 °, and one of them has the maximum peak. A titanyl phthalocyanine pigment or a B-type pigment) is known as a charge generating substance that exhibits stable sensitivity and is easy to synthesize (JP-A-61-61).
-239248).

However, when an organic photoconductor is produced using this B-type pigment charge-generating substance, the black band image defect of the environmental memory is improved, but the residual potential increases remarkably with repeated use. Therefore, in order to prevent the increase in residual charge, when the B-type pigment is used and the concentration of the charge transport material in the charge transport layer is increased, the increase in residual charge is improved.
A problem has been found that image defects called "white spots" are likely to occur. This white spot refers to a dot or linear image defect that is not developed into a halftone or black solid image of reversal development. This phenomenon does not cause the charge to disappear in the image-exposed portion when a latent image is formed on the organic photoconductor. This is probably due to the formation of minute portions, and is considered to be an image defect opposite to the "black spot" that is well known in reversal development.

Further, it has been found that the intermediate layer adjacent to the charge generation layer has a great influence in order to improve the above-mentioned increase in residual charge and enhance the sensitivity of the photoreceptor using the B-type pigment.

For example, a method for forming an intermediate layer by dispersing titanium oxide particles or the like in a copolyamide resin or a methoxymethylated polyamide resin having a chemical structure with a small number of carbon chains between amide bonds such as 6-nylon is used. Is widely known. However, if an attempt is made to improve the residual potential by using such an intermediate layer, “black spot” image defects are likely to occur under high temperature and high humidity, and the black band image defects of the environmental memory described above are also likely to occur.

In order to obtain an electrophotographic photoreceptor in which the above image defects such as black stripes, white spots, and black spots are simultaneously improved and the residual potential is prevented from increasing with repeated use, the present inventors have developed a conventional photoreceptor. The present invention has been accomplished by comprehensively examining the technology.

[0014]

SUMMARY OF THE INVENTION In view of the above problems of the prior art, an object of the present invention is to provide an organic photoreceptor having good potential stability and which does not cause image defects such as black stripes, white spots and black spots. More specifically, it does not generate image defects such as black stripes, white spots, black spots, etc., and the organic photoreceptor has a potential fluctuation that prevents an increase in residual potential with repeated use.
Another object of the present invention is to provide an image forming method, an image forming apparatus and a process cartridge using the organic photoconductor.

[0015]

That is, the object of the present invention is achieved by using an organic photoreceptor having the following constitution.

1. In an organic photoreceptor having a charge generating layer containing a charge generating substance and a charge transporting layer having a charge transporting substance laminated on a conductive support, the charge generating substance is X-ray diffraction by Cu-Kα characteristic X-ray. In the spectrum, a titanyl phthalocyanine pigment having prominent diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.5 ° and 28.7 ° is contained, and the charge transport layer contains a bis (arylethenylphenyl) aniline-based pigment. A stereoisomeric mixture of compounds, wherein the content of the maximum isomer component in the stereoisomeric mixture is 40 to 9
An organophotoreceptor containing 0% by mass of a charge transport material.

2. In an organic photoreceptor having a charge generating layer containing a charge generating substance and a charge transporting layer having a charge transporting substance laminated on a conductive support, the charge generating substance is X-ray diffraction by Cu-Kα characteristic X-ray. In the spectrum, Bragg angles (2θ ± 0.2 °) 7.5 °, 22.6 °, 2
It has remarkable diffraction peaks at 4.5 °, 25.4 ° and 28.7 °, and the maximum diffraction peak is 7.5 ° or 28.7 °.
The titanyl phthalocyanine pigment according to claim 1, wherein the charge transport layer is a stereoisomeric mixture of bis (arylethenylphenyl) aniline compounds, and the content of the maximum isomer component in the stereoisomeric mixture is 40 to 90. An organophotoreceptor containing a charge transporting material in a mass%.

3. In an organic photoreceptor having a charge generating layer containing a charge generating substance and a charge transporting layer having a charge transporting substance laminated on a conductive support, the charge generating substance is X-ray diffraction by Cu-Kα characteristic X-ray. In the spectrum, a titanyl phthalocyanine pigment having prominent diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.5 ° and 28.7 ° is contained, and the charge transport layer contains a bis (arylethenylphenyl) aniline-based pigment. An organophotoreceptor containing a compound, wherein the glass transition point Tgb of the binder resin of the charge transport layer and the glass transition point Tgl of the charge transport layer satisfy the following relationship.

100 ° C. <Tgl <Tgb (Tgb, Tgl
(The unit is ° C.) 4. In an organic photoreceptor having a charge generating layer containing a charge generating substance and a charge transporting layer having a charge transporting substance laminated on a conductive support, the charge generating substance is X-ray diffraction by Cu-Kα characteristic X-ray. In the spectrum, Bragg angle (2θ
± 0.2 °) 7.5 °, 22.6 °, 24.5 °, 2
It contains a titanyl phthalocyanine pigment having prominent diffraction peaks at 5.4 ° and 28.7 ° and a maximum diffraction peak at 7.5 ° or 28.7 °, and the charge transport layer comprises bis (aryl ether). Glass transition point Tgb of the binder resin of the charge transport layer containing the (phenylphenyl) aniline compound
And the glass transition point Tgl of the charge transport layer satisfy the following relationship.

100 ° C. <Tgl <Tgb (Tgb, Tgl
(The unit is ° C.) 5. 5. The organophotoreceptor according to any one of 1 to 4 above, wherein the bis (arylethenylphenyl) aniline compound is a compound represented by the general formula (1).

6. 5. The organophotoreceptor according to any one of 1 to 4 above, wherein the bis (arylethenylphenyl) aniline compound is a compound represented by the general formula (2).

7. 5. The organophotoreceptor according to any one of 1 to 4 above, wherein the bis (arylethenylphenyl) aniline compound is a compound represented by the general formula (3).

8. 5. The organophotoreceptor according to any one of 1 to 4 above, wherein the bis (arylethenylphenyl) aniline compound is a compound represented by the general formula (4).

9. 5. The organophotoreceptor according to any one of 1 to 4 above, wherein the bis (arylethenylphenyl) aniline compound is a compound represented by the general formula (5).

10. 5. The organophotoreceptor according to any one of 1 to 4 above, wherein the bis (arylethenylphenyl) aniline compound is a compound represented by the general formula (6).

11. 11. The organophotoreceptor according to any one of 5 to 10 above, wherein the substituted or unsubstituted aromatic group of Ar ¹ and Ar ² is the general formula (7).

12. 1 wherein the main binder resin of the charge transport layer is polycarbonate
The organic photoreceptor according to any one of 1 to 11.

13. 13. The organic photoreceptor according to any one of 1 to 12 above, which has an intermediate layer between the conductive support and the charge generation layer.

14. 13. The intermediate layer contains N-type semiconductive fine particles and a binder resin.
The organic photoreceptor described.

15. 15. An image forming method, comprising forming an electrophotographic image using the organic photoconductor according to any one of 1 to 14 above.

16. An image forming apparatus, wherein an electrophotographic image is formed using the image forming method described in 15 above.

17. 15. At least the organic photoreceptor according to any one of 1 to 14 above, a charging device, an image exposing device, and a developing device,
A process cartridge comprising at least one of a transfer device and a cleaning device, which is configured to be able to be taken in and out of an image forming apparatus.

The present invention will be described in detail below. The organic photoreceptor of the present invention (hereinafter, also simply referred to as a photoreceptor) is a charge generation layer containing a charge generation material on a conductive support, and an organic photoreceptor having a charge transport layer having a charge transport material laminated thereon. In the X-ray diffraction spectrum by the Cu-Kα characteristic X-ray, the charge generating substance has a Bragg angle (2θ ± 0.2
°) containing a titanyl phthalocyanine pigment (B-type titanyl phthalocyanine pigment) having prominent diffraction peaks at 7.5 ° and 28.7 °, and the charge transporting layer comprises stereoisomerism of a bis (arylethenylphenyl) aniline compound. It is characterized in that it contains a charge-transporting substance in which the content of the maximum isomer component in the stereoisomeric mixture is 40 to 90% by mass.

The organic photoreceptor of the present invention is an organic photoreceptor having a charge generating layer containing a charge generating substance on a conductive support and a charge transporting layer having a charge transporting substance laminated on the charge generating layer. Is an X-ray diffraction spectrum by Cu-Kα characteristic X-ray and shows a Bragg angle (2θ ± 0.2 °) of 7.5.
°, 22.6 °, 24.5 °, 25.4 °, 28.7 °
Has a prominent diffraction peak at 7, and the maximum diffraction peak is 7.
Titanyl phthalocyanine pigment at 5 ° or 28.7 ° (the pigment also belongs to B-type titanyl phthalocyanine pigment)
And the charge transport layer is a stereoisomeric mixture of bis (arylethenylphenyl) aniline compounds, and the content of the maximum isomer component in the stereoisomeric mixture is 40%.
It is characterized in that it contains a charge transporting substance in an amount of ˜90% by mass.

The photosensitive member of the present invention having the above-mentioned constitution can prevent the above-mentioned conflicting image defects, that is, image defects such as black stripes, white spots, and black spots from occurring at the same time, and further, it is possible to prevent the residual image defects due to repeated use. A sharp electrophotographic image can be produced without causing an increase in potential.

That is, a mixture of stereoisomers of a bis (arylethenylphenyl) aniline compound is used as the charge transport material of the charge transport layer, and a charge transport material having a charge transport property is used, and the charge transport layer has a Bragg angle (2θ). ± 0.2 °) 7.
A titanyl phthalocyanine pigment having a remarkable diffraction peak at 5 ° or 28.7 °, or a Bragg angle (2θ ± 0.2
°) 7.5 °, 22.6 °, 24.5 °, 25.4 °,
By stacking on a charge generation layer containing a titanyl phthalocyanine pigment having a remarkable diffraction peak at 28.7 ° and a maximum diffraction peak at 7.5 ° or 28.7 °, the above-mentioned environmental memory It is possible to obtain a photoconductor that can prevent image defects such as black belt-shaped image defects, white spots, and black spots, and prevent a rise in residual potential due to repeated use, and can generate a sharp electrophotographic image. The content of the maximum component of the stereoisomer mixture must be 40 to 90% by mass. When the content of the maximum component is more than 90% by mass, the dispersibility of the charge transport material is deteriorated, which causes fog and a decrease in image density, and the sharpness is apt to be decreased. On the other hand, when the content is less than 40% by mass, the occurrence of white spots is increased, the resolution is lowered, and the stability of electrophotographic characteristics is impaired. In particular, the content rate of the maximum component is 4
5 to 80 mass% is preferable.

The effect as described above can be obtained by using the charge transport material of the stereoisomer mixture of the bis (arylethenylphenyl) aniline compound, so that the compatibility of the charge transport material with the binder of the photosensitive layer, for example, the charge transport layer is improved. It is considered to be favorable, and it is considered that the film quality of the charge transport layer and the electrophotographic characteristics are improved.

The organic photoreceptor of the present invention is an organic photoreceptor in which a charge generating layer containing a charge generating substance and a charge transporting layer containing a charge transporting substance are laminated on a conductive support. The generated substance is an X-ray diffraction spectrum by Cu-Kα characteristic X-ray, and Bragg angle (2θ ± 0.2 °) 7.
It contains a titanyl phthalocyanine pigment having remarkable diffraction peaks at 5 ° and 28.7 °, the charge transport layer contains a bis (arylethenylphenyl) aniline compound, and the glass transition point of the binder resin of the charge transport layer. Tgb
And the glass transition point Tgl of the charge transport layer satisfy the following relationship.

100 ° C. <Tgl <Tgb (Tgb, Tgl
Also, the unit is ° C. Further, the organic photoreceptor of the present invention is an organic photoreceptor in which a charge generating layer containing a charge generating substance and a charge transporting layer having a charge transporting substance are laminated on a conductive support. , The charge generating substance is a Bragg angle (2θ ± 0.2 °) of 7.5 ° in the X-ray diffraction spectrum by Cu-Kα characteristic X-ray, 22.
It has remarkable diffraction peaks at 6 °, 24.5 °, 25.4 °, 28.7 °, and the maximum diffraction peak is 7.5 ° or 2
Containing a titanyl phthalocyanine pigment at 8.7 °,
The charge transport layer contains a bis (arylethenylphenyl) aniline compound, and the glass transition point Tgb of the binder resin of the charge transport layer and the glass transition point Tg of the charge transport layer.
l satisfies the following relationship.

100 ° C. <Tgl <Tgb (Tgb, Tgl
(The unit is ° C.) Since the photoreceptor of the present invention has the above-mentioned constitution, it is possible to simultaneously prevent the above-mentioned conflicting image defects, that is, image defects such as black stripes, white spots, and black spots from occurring, and to be used repeatedly. A sharp electrophotographic image can be produced without increasing the residual potential.

The glass transition point Tgl of the charge transport layer is governed by the binder resin and charge transport material which are the main constituents of the charge transport layer, and the additives other than the charge transport material. Of course, there are other effects of residual solvent concentration,
The residual solvent often adversely affects the electrophotographic characteristics such as charging characteristics and sensitivity of the organic photoreceptor and the physical properties of the film, and it is generally preferable to remove it as much as possible. Further, since the additive amount other than the charge transporting substance is smaller than that of the charge transporting substance, the influence on the glass transition point Tgl is limited by that amount,
In order not to deteriorate the physical properties of the charge transport layer, it is necessary to use its amount and quality (a compound that does not lower the glass transition point Tgl).

The charge-transporting substance of the present invention is a compound having a property of having drift mobility of electrons or holes, or, as another definition, a known method capable of detecting charge-transporting ability such as the Time-Of-Flight method. It refers to a compound that can obtain a detection current due to charge transport.

By the way, in the conventional charge transport layer, a large amount of the charge transport substance is contained in the charge transport layer in order to transport the charges generated in the charge generation layer to the surface of the photoreceptor. Therefore, even if the amount of residual solvent and the amount and quality of other additives are selected and used, it is extremely difficult for the glass transition point Tgl of the charge transport layer to exceed 100 ° C.

In the present invention, a bis (arylethenylphenyl) aniline compound is used as at least one of the charge-transporting substances, and the total molar amount of the charge-transporting substances in the charge-transporting layer is set to a low molar amount so that The above invention was achieved by developing a technique for a charge transport layer which does not lower the glass transition point Tgl and does not lower the charge transport ability, and by combining this technique with a charge generation layer using a B-type titanyl phthalocyanine pigment.

That is, according to the present invention, the glass transition point Tgl of the charge transport layer is set to 100 ° C. or higher, and the charge transport layer is placed on the charge generation layer containing the B-type titanyl phthalocyanine pigment to give a black belt-like structure. It is possible to obtain a photoconductor that can prevent image defects such as white spots and black spots, and prevent the increase in residual potential due to repeated use, and that enables the production of sharp electrophotographic images. The physical properties of such a charge transport layer are as follows: In the charge transport layer, a charge transport substance of a bis (arylethenylphenyl) aniline compound consisting of a stereoisomer mixture is used as a charge transport substance, and the charge transport layer has a low molar number. , For example, 2.0 × 10 ⁻⁴ (mol per unit mass of the charge transport layer)
/ G) to 6.0 × 10 ⁻⁴ (mol / g) by including a charge transporting substance, the glass transition point Tg of the charge transporting layer
This is achieved by reducing the degree of decrease of 1 (the degree of decrease from the glass transition point Tgb of the binder resin). Further, if the total number of moles of the charge transporting material per unit mass of the charge transporting layer is less than 2.0 × 10 ⁻⁴ (mol / g), the sensitivity tends to decrease, and the image density tends to decrease and the fog tends to increase. On the other hand, if it is more than 6.0 × 10 ⁻⁴ (mol / g), it tends to be difficult to set the glass transition point Tgl of the charge transport layer to 100 ° C. or higher, depending on the type of the charge transport material.

That is, a stereoisomeric mixture of bis (arylethenylphenyl) aniline compounds is used as the charge transport material, and the charge transport material is used in a low molar amount so that the physical properties of the charge transport layer are not deteriorated. In addition, it is possible to achieve an organic photoconductor that prevents occurrence of image defects such as white spots and black spots, and that has good electrophotographic characteristics.

In the stereoisomeric mixture of the bis (arylethenylphenyl) aniline compounds, the content of the maximum isomer component in the isomer mixture is preferably 40 to 90% by mass. When the content of the maximum component is more than 90% by mass, the dispersibility of the charge transport material is deteriorated, which causes fog and a decrease in image density, and the sharpness is apt to be decreased. On the other hand, when the content is less than 40% by mass, the occurrence of white spots is increased, the resolution is lowered, and the stability of electrophotographic characteristics is impaired. In particular, the content rate of the maximum component is 45
-80 mass% is preferable.

Further, it is preferable to use a compound in which the molecular weight of the charge transporting substance of the stereoisomer is 500 or more and 1500 or less. If the molecular weight is less than 500, the electrophotographic properties tend to deteriorate, and if it exceeds 1500, the compatibility with the binder resin tends to decrease, and image defects such as white spots and black spots tend to occur.

As the binder resin for the charge transport layer, a polycarbonate resin having excellent electrophotographic properties and film physical properties is preferable. Here, the polycarbonate is a polymer having a carbonate structure (-OCOO-).

The glass transition point Tgb of the polycarbonate resin changes depending on the resin structure, molecular weight, etc., but in the case of commercially available polycarbonate resins, it is in the range of about 160 to 200 ° C. From this fact, when polycarbonate is used as the binder resin for the charge transport layer, the degree of decrease in the glass transition point (from the binder resin) of the charge transport layer due to the charge transport material and other additives should be 60 to 100 ° C or lower. is necessary.

The main binder resin of the present invention means a content of 50% by mass or more based on the total binder resin in the charge transport layer.

The bis (arylethenylphenyl) aniline compound of the present invention refers to a group of compounds having two arylethenylphenyl groups having the same chemical structure at the nitrogen atom of aniline, preferably the above general formula (1). And is preferably a compound represented by the general formula (2) to the general formula (6)
As described above, those having an alkyl group or an alkoxy group at the ortho or para position of the aniline group are preferable.

Further, the charge transporting substance of the stereoisomer mixture has an isomer structure caused by a compound of the charge transporting substance having the same chemical structural formula resulting from different configurations of atoms or atomic groups therein. Say.

Examples of preferred bis (arylethenylphenyl) aniline compounds of the present invention are given below.
The present invention is not limited to the following compound examples. Also, any of these compounds can have a stereoisomeric structure.

[0055]

[Chemical 8]

[0056]

[Chemical 9]

[0057]

[Chemical 10]

[0058]

[Chemical 11]

[0059]

[Chemical 12]

[0060]

[Chemical 13]

[0061]

[Chemical 14]

[0062]

[Chemical 15]

[0063]

[Chemical 16]

[0064]

[Chemical 17]

[0065]

[Chemical 18]

The molecular weight of the charge transport material having a stereoisomeric structure is preferably 500 or more and 1500 or less. By using such a high molecular weight charge transport material, the film quality of the charge transport layer can be improved, and the effects of the present invention described above can be made more prominent.

The method of measuring the glass transition point of the present invention will be described. The measurement of the glass transition point of the present invention is carried out by placing about 1.0 mg of a measurement sample in an aluminum pan, closing the lid and weighing.
This was measured with a heat flux differential scanning calorimeter DSC-50 (manufactured by Shimadzu Corp.) starting from 20 ° C and increasing the temperature to 220 ° C at a temperature rising temperature of 3 ° C / min.

As the measurement sample, the glass transition point of the binder resin of the charge transport layer is Tgb, and the binder resin itself is used as the sample of Tgb.
Is measured using a sample obtained by peeling the charge transport layer from the photoreceptor.

Next, the layer structure of the organic photoreceptor of the present invention will be described. In the present invention, the organic photoconductor means an electrophotographic photoconductor constituted by giving an organic compound at least one of a charge generation function and a charge transport function, which are indispensable for the construction of the electrophotographic photoconductor, All known organic electrophotographic photoconductors such as a photoconductor composed of the organic charge generating substance or the organic charge transporting substance, a photoconductor having a charge generating function and a charge transporting function formed of a polymer complex are included.

The organophotoreceptor of the present invention is characterized by using the B-type titanyl phthalocyanine pigment as a charge generating substance. The B-type titanyl phthalocyanine pigment is also called oxytitanium phthalocyanine and has a chemical formula represented by the following structural formula.

[0071]

[Chemical 19]

(In the formula, X represents a halogen atom, and n is 0.
~ Indicates the number of 1. When X is a chlorine atom, n is 0 to 0.
5 is preferable and 0-0.1 is more preferable. ) The Bragg angle (2θ ± 0.2 °) 7.5 °, 28.7
The method for producing a titanyl phthalocyanine pigment having a remarkable diffraction peak at (and the maximum peak at 7.5 ° or 28.7 °) is described in JP-A-1-239248 and 1-2.
No. 17050 and the like, and the titanyl phthalocyanine pigment produced by these production methods can be produced by using these disclosed production methods. For example, the Bragg angle (2θ ± 2) shown in FIG. 0.2 °) 7.5
An X-ray diffraction spectrum having prominent diffraction peaks at ° and 28.7 ° is shown. The X-ray diffraction spectrum of the titanyl phthalocyanine pigment of FIG. 1 has a maximum diffraction peak at 7.5 ° described above, and in addition, a Bragg angle (2θ ± 0.2 °) of 10.3.
°, 12.3 °, 16.3 °, 18.4 °, 22.6
Clear diffraction peaks are also shown at °, 24.5 °, 25.4 °, and 28.7 °. When the dispersed particle size of the titanyl phthalocyanine pigment is reduced, the low angle of 7.5 °
Peak becomes smaller and the maximum diffraction peak becomes 28.7 °.

The layer structure of the organic photoreceptor containing the above-mentioned charge generating substance is composed of a charge generating layer and a photosensitive layer such as a charge transporting layer on a conductive support. It is more preferable to provide an intermediate layer between the conductive support and the charge generation layer. Each of these layers may be composed of one layer or two or more layers.

Conductive Support The conductive support used for the photoreceptor may be either a sheet or a cylinder, but in order to design the image forming apparatus compactly, the conductive support of the cylindrical shape is used. Is preferred.

The cylindrical conductive support means a cylindrical support required to form an image endlessly by rotating, and has a straightness of 0.1 mm or less and a shake of 0.1 mm.
A conductive support in the following range is preferable. If the straightness and the shake range are exceeded, good image formation becomes difficult.

As the conductive material, a metal drum of aluminum, nickel or the like, a plastic drum on which aluminum, tin oxide, indium oxide or the like is vapor-deposited, or a paper / plastic drum coated with a conductive substance can be used. It is preferable that the conductive support has a specific resistance of 10 ³ Ωcm or less at room temperature.

The conductive support used in the present invention may have a surface on which a sealed alumite film is formed. The alumite treatment is usually carried out in an acidic bath of chromic acid, sulfuric acid, oxalic acid, phosphoric acid, boric acid, sulfamic acid, etc., but anodizing treatment in sulfuric acid gives the most preferable result. In the case of anodizing treatment in sulfuric acid, it is preferable that the sulfuric acid concentration is 100 to 200 g / L, the aluminum ion concentration is 1 to 10 g / L, the liquid temperature is about 20 ° C., and the applied voltage is about 20 V. It is not limited. The average thickness of the anodized film is usually 2
It is preferably 0 μm or less, and particularly preferably 10 μm or less.

Intermediate Layer In the present invention, an intermediate layer having a barrier function may be provided between the conductive support and the photosensitive layer.

In the present invention, an intermediate layer (lower layer) is provided between the support and the photosensitive layer in order to improve the adhesion between the conductive support and the photosensitive layer or prevent charge injection from the support. (Including a pulling layer) can also be provided. Examples of the material of the intermediate layer include a polyamide resin, a vinyl chloride resin, a vinyl acetate resin, and a copolymer resin containing two or more of repeating units of these resins. Among these undercoat resins, a polyamide resin is preferable as a resin that can reduce the increase in residual potential due to repeated use. The thickness of the intermediate layer using these resins is 0.01 to 0.5 μm.
Is preferred.

The intermediate layer preferably used in the present invention includes an intermediate layer using a curable metal resin obtained by thermosetting an organic metal compound such as a silane coupling agent and a titanium coupling agent. The film thickness of the intermediate layer using the curable metal resin is preferably 0.1 to 2 μm.

The intermediate layer preferably used in the present invention includes an intermediate layer in which N-type semiconductive fine particles having a hydrophobic surface treatment are dispersed in a binder. For example, the average particle size after the silica / alumina treatment and the surface treatment with a silane compound is 0.
An intermediate layer in which titanium oxide having a thickness of 0 to 1 μm is dispersed in a polyamide resin can be mentioned. The thickness of such an intermediate layer is 1
˜20 μm is preferred.

The N-type semiconductive fine particles are fine particles having a property that the conductive carrier is an electron. That is, the property that the conductive carrier is an electron means that the N-type semiconductive fine particles are contained in the insulating binder to efficiently block the hole injection from the substrate, and the electron from the photosensitive layer is blocked. On the other hand, it refers to a substance that does not exhibit blocking properties.

Specific examples of the N-type semiconductive fine particles include fine particles of titanium oxide (TiO ₂ ), zinc oxide (ZnO), tin oxide (SnO ₂ ), etc.
Particularly, titanium oxide is preferably used.

The average particle size of the N-type semiconductive fine particles used in the present invention is 10 nm or more and 500 in number average primary particle size.
It is preferably in the range of nm or less, more preferably 10
nm to 200 nm, particularly preferably 15 nm to 50 n
m.

The number average primary particle diameter is within the above range N
The intermediate layer using the type semiconductive fine particles can have a fine dispersion in the layer, and has sufficient potential stability and a black spot generation preventing function.

The number average primary particle size of the N-type semiconductive fine particles is, for example, in the case of titanium oxide, magnified 10,000 times by transmission electron microscope observation, and 100 particles are randomly observed as primary particles to obtain an image. It is measured as the number average diameter of Feret's diameter by analysis.

The N-type semiconductive fine particles used in the present invention may have a dendritic, needle-like, or granular shape, and the N-type semiconductive fine particles having such a shape are, for example, titanium oxide particles. As the crystal type, there are anatase type, rutile type, amorphous type, and the like, but any crystal type may be used, or two or more crystal types may be mixed and used. Among them, the rutile type is the best.

One of the hydrophobizing surface treatments carried out on the N-type semiconductive fine particles of the present invention is that the surface treatment is carried out a plurality of times, and the last surface treatment is reactive among the plurality of surface treatments. The surface treatment is performed with an organosilicon compound. Also,
Among the plurality of surface treatments, at least one surface treatment is at least one kind of surface treatment selected from alumina, silica, and zirconia, and the surface treatment of the reactive organosilicon compound is finally performed. preferable.

Alumina treatment, silica treatment, and zirconia treatment mean that alumina, silica, and
Alternatively, it refers to a treatment for precipitating zirconia, and the alumina, silica, and zirconia deposited on these surfaces also include hydrates of alumina, silica, and zirconia. Further, the surface treatment of the reactive organic silicon compound means that the reactive organic silicon compound is used in the treatment liquid.

As described above, the surface treatment of N-type semiconductive fine particles such as titanium oxide particles is performed at least twice, so that the surface of the N-type semiconductive fine particles is uniformly coated (treated). When the treated N-type semiconductive fine particles are used in the intermediate layer, the dispersibility of the N-type semiconductive fine particles such as titanium oxide particles in the intermediate layer is improved, and the electrophotographic characteristics, especially the residual potential after repeated use are improved. It is possible to increase stability and further improve effects of black spots, environmental memory, and the like.

Charge Generating Layer The charge generating layer contains the above-mentioned B-type titanyl phthalocyanine pigment as a charge generating substance (CGM). Other than the B-type titanyl phthalocyanine pigment, other charge generating substances may be used if necessary. For example, other phthalocyanine pigments, azo pigments, perylene pigments, and azurenium pigments can be used in combination, but in order to sufficiently secure the effect of the present invention, the B-type titanyl phthalocyanine pigment is used in an amount of 50% by mass of the entire charge generating substance. The above is preferable.

As other substances, if necessary, a binder resin and other additives may be contained. When a binder is used as a CGM dispersion medium in the charge generation layer, a known resin can be used as the binder, and the most preferable resin is a formal resin, a butyral resin, a silicone resin, a silicone-modified butyral resin,
Examples thereof include phenoxy resin. The ratio of the binder resin to the charge generating substance is preferably 20 to 600 parts by mass with respect to 100 parts by mass of the binder resin. By using these resins, the increase in residual potential due to repeated use can be minimized. The thickness of the charge generation layer is 0.01 μm to 2 μm
m is preferred.

Charge Transport Layer The charge transport layer uses a stereoisomer mixture as a charge transport material (CTM) and contains a binder resin for dispersing CTM to form a film. Other substances may optionally contain additives such as antioxidants.

As the charge-transporting substance (CTM), a known charge-transporting substance may be used in combination with the charge-transporting substance of the stereoisomer mixture described above. For example, triphenylamine derivative, hydrazone compound, styryl compound,
Combined use of benzidine compounds, butadiene compounds, etc.
Can be used. These charge transport materials are usually dissolved in a suitable binder resin to form a layer.

Examples of the resin used for the charge transport layer (CTL) are polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd. Resins, polycarbonate resins, silicone resins, melamine resins, copolymer resins containing two or more of the repeating units of these resins, these insulating resins, and poly-
Examples include polymer organic semiconductors such as N-vinylcarbazole.

The most preferable binder for these CTLs is a polycarbonate resin. Polycarbonate resin is most preferable in improving dispersibility of CTM and electrophotographic characteristics. Further, in the case of a photoreceptor having a charge transport layer as a surface layer, a polycarbonate that is resistant to mechanical abrasion is preferable, and as such a polycarbonate, a polycarbonate having an average molecular weight of 2,000,000 to 25,000 is preferable. Here, the average molecular weight may be any of number average molecular weight, weight average molecular weight, and viscosity average molecular weight. The ratio of the binder resin to the charge transport material is preferably 10 to 200 parts by mass with respect to 100 parts by mass of the binder resin. Also, the thickness of the charge transport layer is 10 to 40 μm.
m is preferred.

Further, it is preferable that the charge transport layer contains an antioxidant. The antioxidant is a typical one that does not prevent the action of oxygen on the auto-oxidizing substance existing in the organic photoreceptor or on the surface of the organic photoreceptor under the conditions of light, heat, discharge, etc. It is a substance that has an inhibitory property. Typically, the following compounds are listed.

[0098]

[Chemical 20]

[0099]

[Chemical 21]

[0100]

[Chemical formula 22]

[0101]

[Chemical formula 23]

The charge transport layer may have a layer structure of two or more layers. In this case, a layer structure in which a function as a protective layer is added to the charge transport layer on the surface and abrasion resistance with a cleaning blade or the like is enhanced is preferable.

The solvent or dispersion medium used for forming the intermediate layer, the photosensitive layer, the protective layer and the like includes n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine,
N, N-dimethylformamide, acetone, methyl ethyl ketone, methyl isopropyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, dichloromethane, 1,2-dichloroethane, 1,2-dichloropropane, 1,1,2-trichloroethane, 1,
1,1-trichloroethane, trichloroethylene, tetrachloroethane, tetrahydrofuran, dioxolane,
Dioxane, methanol, ethanol, butanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl cellosolve and the like can be mentioned. The present invention is not limited to these, but dichloromethane, 1,2-dichloroethane, methyl ethyl ketone and the like are preferably used. Further, these solvents can be used alone or as a mixed solvent of two or more kinds.

As the coating processing method for producing the electrophotographic photosensitive member of the present invention, coating processing methods such as dip coating, spray coating and circular amount regulation type coating are used. Does not dissolve the lower layer as much as possible,
In order to achieve uniform coating processing, it is preferable to use a coating processing method such as spray coating or circular amount regulation type (a circular slide hopper type is a typical example) coating. The spray coating is described in detail in, for example, JP-A-3-90250 and JP-A-3-269238, and the circular amount regulating coating is described in JP-A-58-1890.
This is described in detail in Japanese Patent No. 61.

Next, the image forming apparatus of the present invention will be described. FIG. 3 is a sectional configuration diagram of an image forming apparatus as an example of the image forming method of the present invention.

In FIG. 3, reference numeral 50 denotes a photosensitive drum (photosensitive member) which is an image bearing member, and an organic photosensitive layer is coated on the drum,
A photosensitive member having the resin layer of the present invention applied thereon is grounded and driven and rotated clockwise. Reference numeral 52 denotes a scorotron charger (charging means) for uniformly charging the peripheral surface of the photosensitive drum 50 by corona discharge. This charger 5
Prior to the charging by 2, the exposure may be performed by the pre-charge pre-exposure unit 51 using a light emitting diode or the like to eliminate the history of the photo conductor in the pre-image formation to eliminate the charge on the peripheral surface of the photo conductor.

After the photosensitive member is uniformly charged, an image exposing device 53 as an image exposing means performs image exposure based on an image signal. The image exposure device 53 in this figure uses a laser diode (not shown) as an exposure light source. Rotating polygon mirror 53
1, the light whose optical path is bent by the reflection mirror 532 through the f.theta. Lens, etc., scans the photosensitive drum to form an electrostatic latent image.

Here, the reversal development process of the present invention is to uniformly charge the surface of the photoconductor by the charger 52 and develop the image-exposed region, that is, the exposed portion potential (exposed region) of the photosensitive member. It is an image forming method that visualizes by a step (means). On the other hand, the unexposed portion potential is not developed by the developing bias potential applied to the developing sleeve 541.

The electrostatic latent image is then developed by the developing device 54 as a developing means. A developing device 54 containing a developer composed of toner and carrier is provided on the periphery of the photosensitive drum 50, and development is performed by a developing sleeve 541 that contains a magnet and holds the developer and rotates.
Inside the developing unit 54, the developer stirring and conveying members 544, 543,
The developer is constituted by a conveyance amount regulating member 542 and the like, and the developer is agitated and conveyed to be supplied to the developing sleeve, and the supply amount thereof is controlled by the conveyance amount regulating member 542. The amount of the developer conveyed varies depending on the linear velocity of the applied organic electrophotographic photosensitive member and the specific gravity of the developer, but is generally 20 to 2
It is in the range of 00 mg / cm ² .

The developer is, for example, a carrier having the above-mentioned ferrite as a core and coated with an insulating resin around it, a coloring agent such as carbon black, a charge control agent, and a low molecular weight polyolefin mainly composed of the above-mentioned styrene-acrylic resin. The toner is formed by externally adding silica, titanium oxide, or the like to the colored particles made of, and the developer is transported to the developing area with the layer thickness regulated by the transport amount regulating member, and development is performed. At this time, normally, a DC bias is applied between the photosensitive drum 50 and the developing sleeve 541, and if necessary, an AC bias voltage is applied to develop. Further, the developer is developed in a state of being in contact with or non-contacting with the photoreceptor. The potential of the photoconductor is measured by providing a potential sensor 547 above the developing position as shown in FIG.

After the image formation, the recording paper P is fed to the transfer area by the rotation operation of the paper feed roller 57 when the transfer timing is adjusted.

In the transfer area, the transfer electrode (transfer means: transfer device) 58 operates on the peripheral surface of the photosensitive drum 50 in synchronization with the transfer timing, and the recording paper P fed is charged with the opposite polarity to the toner. To transfer the toner.

Next, the recording paper P is separated by a separating electrode (separator) 59.
Is discharged by the peripheral surface of the photoconductor drum 50 and conveyed to the fixing device 60. The heat roller 601 and the pressure roller 602 heat and pressurize the toner to fuse the toner, and then the paper is discharged from the outside of the device via the paper discharge roller 61. Is discharged to. The transfer electrode 58 and the separation electrode 59 stop the primary operation after passing the recording paper P and prepare for the next toner image formation. In FIG. 3, a transfer band electrode of a corotron is used as the transfer electrode 58. The setting condition of the transfer electrode varies depending on the process speed (peripheral speed) of the photoconductor and cannot be specified unconditionally. For example, the transfer current is +
100 to +400 μA, transfer voltage +500 to +
2000V can be used as the set value.

On the other hand, the photosensitive drum 50 after separating the recording paper P removes and cleans the residual toner by pressing the blade 621 of the cleaning device (cleaning means) 62.
The pre-charging pre-exposure unit 51 again removes electricity and the charger 52 charges, and the next image forming process starts.

Reference numeral 70 denotes a detachable process cartridge in which a photoconductor, a charger, a transfer device, a separator and a cleaning device are integrated.

The organic electrophotographic photoconductor of the present invention is generally applied to electrophotographic devices such as electrophotographic copying machines, laser printers, LED printers and liquid crystal shutter type printers. It can be widely applied to devices such as printing, plate making, and facsimile.

[0117]

The present invention will be described in detail below with reference to examples, but the embodiments of the present invention are not limited thereto. In the text, "part" represents part by mass.

Example 1 (Example corresponding to claims 1 and 2) Synthesis Example 1 (Synthesis example of Exemplified compound T20)

[0119]

[Chemical formula 24]

10 g of the compound represented by the above formula was dissolved in 32 g of phosphorus oxychloride, heated to 50.degree. C., and 22 ml of dimethylformamide was added dropwise little by little (heat generation of 40 to 40 ° C.).
70 ° C). The reaction solution was stirred for 15 hours while controlling the temperature to around 90 ° C. After cooling to 40 ° C, excess phosphorus oxychloride was sufficiently hydrolyzed and the precipitated crystals were separated by filtration, suspended in water and washed, and the washing was repeated until the washing liquid became neutral. Obtained 9.25 g (77%) of the represented bisformyl compound.

[0121]

[Chemical 25]

2 g of the bisformyl compound obtained above,
4.3 g of the phosphonate compound represented by the following structural formula was dissolved in 20 ml of dimethylformamide. 20 reaction liquids
While maintaining the temperature around 0 ° C, 1.0 g of sodium methoxide was added little by little (heat generation). After stirring for 4 hours, water 30
After adding ml, the product was purified by a conventional method to give yellow crystals 3.3.
g (81%) was obtained. When this yellow crystal was subjected to elemental analysis and mass spectrometry, the results shown in Table 1 below were obtained, and it was confirmed that the compound was T20.

[0123]

[Chemical formula 26]

Elemental analysis (C ₅₃ H ₄₉ N)

[0125]

[Table 1]

Mass spectrum (C ₅₃ H ₄₉ N) Mw (calculated value) = 699 Mw ⁺ (measured value) = 699 The compound of T20 obtained by the above synthesis is designated as T20-1. This T20-1 is the following liquid chromatography (HP
CL) measurement result cis-cis / cis-trans
/ Trans-trans mixing ratio is 1.1 / 2.2 /
It was 1.0. Incidentally, T20cis-cis, T20t
The structural formulas of trans-trans and T20cis-trans are shown below.

Measurement conditions for liquid chromatography Measuring instrument: Shimadzu LC6A (manufactured by Shimadzu Corporation) Column: CLC-SIL (manufactured by Shimadzu Corporation) Detection wavelength: 290 nm Mobile phase: n-hexane / dioxane = 10-500 / 1 Flow rate of mobile phase : About 1 ml / min sample (T20) solvent: n-hexane / dioxane =
10/1 sample (T20): 3 mg / 10 ml of solvent

[0128]

[Chemical 27]

The T20-1 obtained above was analyzed by liquid chromatography for cis-cis form and cis-tran.
A compound separated into an s form and a trans-trans form was also obtained. T20c-c of these cis-cis bodies
T20 of the cis-trans form was replaced with T20c-t, tra
Let T20 of the ns-trans body be T20t-t. T
20-1 and T20c-c, T20c-t, T20t-t
As shown in Table 2, cis-cis / cis-trans / trans- is used by changing the mixing ratio.
Compounds T20-2 to T20-6 having a trans mixing ratio were prepared.

Preparation of Photoreceptor 1 <Intermediate Layer> Titanium oxide SMT500SAS (first: silica / alumina treatment, second: methylhydrogenpolysiloxane treatment: titanium oxide particle size 35 nm: manufactured by Teika) 300 parts Polyamide resin CM8000 ( (Manufactured by Toray Industries, Inc.) 100 parts Methanol 1000 parts Titanium oxide, polyamide resin, and methanol were added to the same container and dispersed using an ultrasonic homogenizer to prepare a coating liquid for the intermediate layer. This coating solution was applied onto a cylindrical aluminum substrate by dip coating, and heat-cured at 110 ° C. for 1 hour to form an intermediate layer with a dry film thickness of 4 μm.

<Charge Generating Layer> B-type titanyl phthalocyanine pigment (titanyl phthalocyanine pigment having X-ray diffraction spectrum shown in FIG. 1) 60 parts Silicone-modified butyral resin (X-40-1211M: manufactured by Shin-Etsu Chemical Co., Ltd.) 700 parts 2- Butanone (2000 parts) was mixed and dispersed for 10 hours using a sand mill to prepare a charge generation layer coating liquid. This coating solution was applied onto the intermediate layer by a dip coating method to form a charge generation layer having a dry film thickness of 0.2 μm.

<Charge Transport Layer> Charge transport material (T20-1) 225 parts Polycarbonate (viscosity average molecular weight: 20,000) 300 parts Antioxidant (exemplary compound 1-3) 6 parts Dichloromethane 2000 parts are mixed and dissolved. Then, a charge transport layer coating solution was prepared. This coating solution was applied onto the charge generating layer by a dip coating method to form a charge transporting layer having a dry film thickness of 24 μm, to prepare a photoreceptor 1.

Preparation of Photoreceptors 2-9 The charge transport material (T20-1) used in Photoreceptor 1 was replaced with T20.
-2-T20-6, T20c-c, T20c-t, T2
Photoconductors 2 to 9 were prepared in the same manner as the photoconductor 1 except that the isomer mixture ratio was changed as shown in Table 2 instead of 0t-t.

Preparation of Photoreceptor 10 Photoreceptor 10 was prepared in the same manner except that the charge transporting material (T20-1) used in Photoreceptor 1 was replaced with charge transporting material T101 having the following chemical structure.

[0135]

[Chemical 28]

Preparation of Photoreceptor 11 The B-type titanyl phthalocyanine pigment of the charge generation layer used in the photoreceptor 1 was replaced with the Y-type titanyl phthalocyanine pigment (Cu-K
Bragg angle of 2 in X-ray diffraction spectrum by α characteristic X-ray
The photoconductor 1 except that the titanyl phthalocyanine pigment having the maximum peak at 27.2 ± 0.2 ° at θ: FIG. 2) was used instead.
Photoreceptor 11 was prepared in the same manner as in.

[0137]

[Table 2]

Evaluation As an evaluation machine, a digital copying machine Konica7 manufactured by Konica
075 (having corona charging, laser exposure, reversal development, electrostatic transfer, nail separation, blade cleaning, cleaning auxiliary brush roller adoption process) was used, and photoconductors 1 to 11 were mounted on the copying machine and evaluated. The cleaning property and the image evaluation were performed by copying an original image in which a character image having a pixel ratio of 7%, a human face photograph, a solid white image, and a solid black image are equally divided into A4 neutral papers. High temperature and high humidity environment with severe environmental conditions: HH environment (30
℃ environment, 80% RH and low temperature and low humidity environment: LL environment (10 ° C,
20% RH), 10,000 copies were continuously made, and a total of 20,000 copies were made to produce halftones, solid white images, and solid black images, and the following evaluations were performed.

Evaluation standard image density (measured using RD-918 manufactured by Macbeth Co.)
The relative reflection density was measured with the reflection density of the paper being "0".
Images were evaluated at the initial stage and after copying each 10,000 sheets. ): Black solid image is 1.2 or more ○: Black solid image is less than 1.2 to 1.0 ×: Black solid image is less than 1.0 Fog (solid white image after initial copying and 10,000 copies each) Judgment by visual inspection: ⊚: No fog occurred during copying under both environmental conditions ○: Fog with a density of 0.01 to 0.02 occurred in either environment ×: Density 0 in either environment Fog of 0.03 or more occurred Image defect evaluation environment memory: High temperature and high humidity environment (30 ° C, 80% RH)
After copying 10,000 sheets, the Konica 7075 copying machine was left under the same conditions for 24 hours, and then under low humidity and low temperature (L
L: 10 ° C., 20% RH), and after 30 minutes, copied. Copy a halftone image with a density of 0.4 in the original image to a density of 0.4.
= Maximum density-minimum density A: ΔHD is 0.05 or less (good) B: ΔHD is larger than 0.05 and less than 0.1 (no problem in practical use) C: ΔHD is 0.1 or more (practical use) There is a problem above) Black spots (after each of 10,000 copies described above, 100 sheets of solid white copy images were made and evaluated) Regarding black spots, the periodicity coincides with the period of the photoconductor, and there are visible black spots. , A4 size was determined by the number.

A: Black spot frequency of 0.4 mm or more: All copied images are 3 pieces / A4 or less (good) B: Black spot frequency of 0.4 mm or more: 4 pieces / A4 or more, 1
0 or more / A4 or less occurred 1 or more (no problem in practical use) C: 0.4 mm or more black spot frequency: 11 / A4 or more occurred 1 or more (problem in practical use) White spots (10,000 each above) After copying one sheet, 100 halftone images were further prepared and evaluated. The evaluation of white spots was determined by the number of white spots per A4 size that the periodicity coincides with the period of the photoconductor.

A: White spot frequency of 0.4 mm or more: All copied images are 3 / A4 or less B: White spot frequency of 0.4 mm or more: 4 / A4 or more, 1
9 / A4 or less occurred 1 or more C: 0.4 mm or more white spot frequency: 20 / A4 or more occurred 1 or more resolution (determined by the ease of distinguishing character images) After copying 10,000 sheets each Character images of 3 points and 5 points were formed and evaluated according to the following criteria.

⊚: 3 points, 5 points were clear and easily readable ○: 3 points were partially unreadable, 5 points were clear and easily readable ×: 3 points were almost unreadable, 5 Some or all of the points are not readable. Other evaluation conditions The other evaluation conditions using the digital copying machine Konica 7075 are set as follows.

Charging conditions Charging device: Scorotron charger, initial charging potential of -750
V exposure condition Set the exposure amount to make the exposed portion potential -50V.

Development conditions DC bias: -550V The developer is a carrier having ferrite as a core and coated with an insulating resin, a styrene acrylic resin as a main material, a colorant such as carbon black, a charge control agent, a low molecular weight of the present invention. A toner developer in which silica, titanium oxide, etc. are externally added to colored particles made of polyolefin is used.

Transfer conditions Transfer pole: Corona charging method Cleaning conditions Hardness 70 °, impact resilience 34%, thickness 2 at cleaning part
(Mm), a cleaning blade having a free length of 9 mm was brought into contact with the counter by a weight load method so that the linear pressure was 20 (N / m).

The evaluation results are shown in Table 3.

[0147]

[Table 3]

As is apparent from Table 3, the photoconductor 1 containing the charge transport material of the stereoisomer mixture in the charge transport layer, and the content ratio of the maximum isomer component of the mixture was within the range of the present invention,
In Nos. 2, 4, 5, and 6, image characteristics such as image density, fog, and resolution are good, and there are few image defects such as environmental memory, black spots, and white spots, and all characteristics are improved in a balanced manner. ing. Especially, the maximum isomer content is 51
The improvement effect is remarkable for the photoconductors 1, 4, and 5 of 80% by mass.
On the other hand, in the photoconductor 3 in which the maximum isomer component of the mixture is 37.5% by mass, which is outside the range of the present invention, the occurrence of white spots is increased and the resolution is also lowered. The maximum isomer component is 1
In the case of the photoconductors 7, 8 and 9 of 00 mass%, black spots and white spots often occur, and the image density and the resolution are lowered. Further, in the photoconductor 10 using the charge transport material T101 having no stereoisomer, white spots are remarkably generated and the resolution is lowered. In addition, the photoreceptor 11 using the Y-type titanyl phthalocyanine pigment as the charge generating substance is significantly deteriorated in environmental memory and resolution.

Example 2 (Example corresponding to claims 1 and 2) Synthesis example 2 (Synthesis example of exemplified compound T50)

[0150]

[Chemical 29]

10 g of the compound represented by the above formula was dissolved in 34 g of phosphorus oxychloride, heated to 50 ° C., and 23 ml of dimethylformamide was added dropwise little by little (heat generation of 40 to 40 ° C.).
70 ° C). The reaction solution was stirred for 15 hours while controlling the temperature to around 90 ° C. After cooling to 40 ° C, excess phosphorus oxychloride was sufficiently hydrolyzed and the precipitated crystals were separated by filtration, suspended in water and washed, and the washing was repeated until the washing liquid became neutral. 9.43 g (78%) of the represented bisformyl compound were obtained.

[0152]

[Chemical 30]

2 g of the bisformyl compound obtained above,
4.3 g of the phosphonate compound represented by the following structural formula was dissolved in 20 ml of dimethylformamide. 20 reaction liquids
While maintaining the temperature around 0 ° C, 1.0 g of sodium methoxide was added little by little (heat generation). After stirring for 4 hours, water 30
After adding ml, the product was purified by a conventional method to give yellow crystals 3.3.
g (81%) was obtained. When this yellow crystal was subjected to elemental analysis and mass spectrometry, the results shown in Table 4 below were obtained, and it was confirmed that the compound was T50.

[0154]

[Chemical 31]

Elemental analysis (C ₄₀ H ₃₉ N)

[0156]

[Table 4]

Mass spectrum (C ₄₀ H ₃₉ N) Mw (calculated value) = 533 Mw ⁺ (measured value) = 533 The compound of T50 obtained by the above synthesis is designated as T50-1. This T50-1 is the following liquid chromatography (HP
CL) measurement result cis-cis / cis-trans
/ Trans-trans mixing ratio is 1.2 / 2.0 /
It was 1.0. Incidentally, T50cis-cis, T50t
The structural formulas of trans-trans and T50cis-trans are shown below.

[0158]

[Chemical 32]

The T50-1 obtained above was analyzed by liquid chromatography for cis-cis form and cis-tran form.
A compound separated into an s form and a trans-trans form was also obtained. T50c-c of these cis-cis bodies was changed to T50c-c,
T50 of the cis-trans form is converted to T50c-t, tra
The T50 of the ns-trans body is referred to as T50t-t. T
50-1 and T50c-c, T50c-t, T50t-t
4 of the above compounds and changing the mixing ratio, as shown in Table 5, cis-cis / cis-trans / trans-
Compounds of T50-2 to 50-6 having a mixing ratio of trans were prepared.

Preparation of Photoreceptors 12 to 20 The charge transport material (T20-1) used in the photoreceptor 1 was replaced with T50.
-1 to T50-6, T50c-c, T50c-t, T5
Photosensitive members 12 to 20 were produced in the same manner as the photosensitive member 1 except that the isomer mixture ratio was changed as shown in Table 5 instead of 0t-t.

Preparation of Photoreceptor 21 The B-type titanyl phthalocyanine pigment of the charge generation layer used in the photoreceptor 1 was replaced with the Y-type titanyl phthalocyanine pigment (Cu-K
Bragg angle of 2 in X-ray diffraction spectrum by α characteristic X-ray
The charge transport material (T20-) was added to the titanyl phthalocyanine pigment having a maximum peak at 27.2 ± 0.2 °.
A photoconductor 21 was produced in the same manner as the photoconductor 1 except that 1) was replaced with T50-1.

[0162]

[Table 5]

Example 1 using the photoconductors 12 to 21
The same evaluation as was done. The results are shown in Table 6.

[0164]

[Table 6]

As is clear from Table 6, the photoconductors 12, 13 in which the charge transport layer contains the charge transport substance of the stereoisomer mixture, and the maximum isomer component of the mixture is within the scope of the present invention.
Nos. 15, 16, and 17 have good image characteristics such as image density, fog, and resolution, and have few image defects such as environmental memory, black spots, and white spots, and all characteristics are improved in a balanced manner. . Especially, the maximum isomer content is 4
The improvement effect is remarkable for the photoreceptors 12, 15 and 16 of 8 to 80 mass%. On the other hand, the maximum isomer component of the mixture is 37.5.
In the photoconductor 14 whose mass% is outside the range of the present invention, the occurrence of white spots is increasing and the resolution is also decreasing. Further, in the photoconductors 18, 19 and 20 in which the maximum isomer component is 100% by mass, black spots and white spots often occur, and the image density and resolution are lowered. In addition, the photoreceptor 21 using the Y-type titanyl phthalocyanine pigment as the charge generating substance is significantly deteriorated in environmental memory and resolution.

Example 3 (Example Corresponding to Claims 3 and 4) Preparation of Photoreceptor 22 <Intermediate Layer> Titanium oxide SMT500SAS (first time: silica-alumina treatment, second time: methylhydrogenpolysiloxane treatment: taker) 300 g Polyamide resin CM8000 (Toray) 100 g Methanol 1000 g Titanium oxide, polyamide resin, and methanol were added to the same container and dispersed using an ultrasonic homogenizer to prepare a coating solution for the intermediate layer. This coating solution was applied onto a cylindrical aluminum substrate by dip coating, and heat-cured at 110 ° C. for 1 hour to form an intermediate layer with a dry film thickness of 4 μm.

<Charge Generation Layer> B-type titanyl phthalocyanine pigment (titanyl phthalocyanine pigment having the X-ray diffraction spectrum shown in FIG. 1) 60 g Silicone-modified butyral resin (X-40-1211M: manufactured by Shin-Etsu Chemical Co., Ltd.) 700 g 2-butanone 2000 ml Were mixed and dispersed for 10 hours using a sand mill to prepare a charge generation layer coating solution. This coating solution was applied onto the intermediate layer by a dip coating method to form a charge generation layer having a dry film thickness of 0.2 μm.

<Charge Transport Layer> Charge transport material (T20-1) 230 g Polycarbonate Z (polycarbonate having the following structural formula: viscosity average molecular weight 30,000) 300 g Antioxidant (Exemplified Compound 1-3) 6 g Dichloromethane 2000 ml was mixed. , And dissolved to prepare a charge transport layer coating solution. This coating solution is applied onto the charge generation layer by a dip coating method, and then dried at 100 ° C. for 60 minutes to reduce the residual solvent amount to 0.1% by mass or less to form a charge transport layer having a dry film thickness of 24 μm. Then, the photoconductor 22 was formed. The solid content of the charge transport layer of the photoconductor 22 is the total amount of the charge transport material, polycarbonate Z, and antioxidant: 536 g, and the number of moles of 230 g of the charge transport material is 0.329 mol. The number of moles of the charge transport material is 6.1 ×
It is 10 ^-4 mol / g.

[0169]

[Chemical 33]

Preparation of Photoreceptors 23 to 27 Photoreceptors 23 to 27 were prepared in the same manner as the photoreceptor 22 except that the amount of the charge transport material (T20-1) used in the photoreceptor 22 was changed as shown in Table 7. did.

Preparation of Photoreceptor 28 The B-type titanyl phthalocyanine pigment of the charge generation layer used in the photoconductor 22 was replaced with the Y-type titanyl phthalocyanine pigment (Cu-
A photoconductor 28 was prepared in the same manner as the photoconductor 22 except that a titanyl phthalocyanine pigment having a maximum peak at 27.2 ± 0.2 ° at a Bragg angle of 2θ in the X-ray diffraction spectrum by the Kα characteristic X-ray was used. did.

[0172]

[Table 7]

Evaluation The evaluation was performed in the same manner as in Example 1.

The evaluation results are shown in Table 8.

[0175]

[Table 8]

As is clear from Table 8, the charge transport layer contains the charge transport substance of the stereoisomer mixture, and the charge transport layer contains T
photoconductor 24 having a gl of 122 to 161 ° C. higher than 100 ° C.
Nos. 27 to 27 are less likely to cause image defects such as environmental memory, black spots, and white spots. Except for the photoconductor 27 (the concentration of the charge transport material is low and the image concentration is low), image density, fog, The image characteristics such as resolution are good, and all the characteristics are improved in a balanced manner. On the other hand, the Tgl of the charge transport layer is 75 ° C. or 89 ° C.
In No. 3, the occurrence of white spots increased and the resolution also decreased.
Further, the photoreceptor 28 using the Y-type titanyl phthalocyanine pigment as a charge generating substance has a remarkable deterioration in environmental memory and resolution.

Example 4 (Examples corresponding to claims 3 and 4) Preparation of photoconductors 29 to 41 Table 9 shows the types and amounts of the charge transport substances used in the photoconductor 22.
The same as the photoconductor 22 except that the photoconductor 2 is changed to
9-41 were produced.

Preparation of Photoreceptor 42 The B-type titanyl phthalocyanine pigment of the charge generation layer used in the photoconductor 22 was replaced with the Y-type titanyl phthalocyanine pigment (Cu-
The type and amount of the charge transport material are shown in Table 9 instead of the titanyl phthalocyanine pigment having the maximum peak at 27.2 ± 0.2 ° at the Bragg angle 2θ in the X-ray diffraction spectrum by the Kα characteristic X-ray. A photoconductor 42 was produced in the same manner as the photoconductor 22 except for the above.

[0179]

[Table 9]

Example 1 using the photoconductors 29 to 42
The same evaluation as was done. The results are shown in Table 10.

[0181]

[Table 10]

As is apparent from Table 10, the photoconductors 29 to 33 containing the charge transporting substance of the stereoisomer mixture in the charge transporting layer and having Tgl of the charge transporting layer higher than 100 ° C. were found to have image density, fog and resolution. The image characteristics such as the above are good, and the occurrence of image defects such as environmental memory, black spots and white spots is small, and all the characteristics are improved in a balanced manner. on the other hand,
Even if the Tgl of the charge transport layer is 115 ° C., 113 ° C., 117 ° C. and higher than 100 ° C., the photoconductors 34, 35, and 36 in which the charge transport material is not a stereoisomer mixture have a large decrease in image density and a deterioration in resolution. is doing. Even if the charge transport material is a stereoisomer mixture, the Tgl of the charge transport layer is 10 or less.
The occurrence of white spots also increases in the photoconductors 37 to 41 lower than 0 ° C.
The resolution is degraded. In addition, the photoreceptor 42 using the Y-type titanyl phthalocyanine pigment as the charge generating substance is significantly deteriorated in environmental memory and resolution.

[0183]

As is apparent from the examples, by using the organic photoreceptor having the constitution of the present invention, a sharp electrophotographic image can be obtained without causing environmental memory, white spots or black spots. it can. Further, it is possible to provide an image forming method, an image forming apparatus and a process cartridge which can achieve a good electrophotographic image using the organic photoreceptor.

[Brief description of drawings]

FIG. 1 shows an X-ray diffraction spectrum of a titanyl phthalocyanine pigment having prominent diffraction peaks at 7.5 ° and 28.7 °.

FIG. 2 shows an X-ray diffraction spectrum of a titanyl phthalocyanine pigment having a maximum peak at 27.2 ± 0.2 °.

FIG. 3 is a cross-sectional configuration diagram of an image forming apparatus as an example of the image forming method of the present invention.

[Explanation of symbols]

50 photoconductor drum (photoconductor) 51 Pre-charge exposure unit 52 Charger 53 Image exposure device 54 Developer 541 Development sleeve 543,544 developer stirring and conveying member 547 potential sensor 57 Paper Feed Roller 58 transfer electrode 59 Separation electrode (separator) 60 fixing device 61 Paper ejection roller 62 cleaning device 70 Process cartridge

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 5/14 G03G 5/14 101E (72) Inventor Takeshi Shimoda 2970 Ishikawa-cho, Hachioji, Tokyo Konica Stock Company (72) Inventor Hirofumi Hayata 2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica Stock Company F-term (reference) 2H068 AA13 AA19 AA20 AA35 AA37 AA41 AA44 BA12 BA13 BA14 BA39 BB25 BB55 CA29 FA27

Claims (17)

[Claims] 1. An organic photoreceptor having a charge generating layer containing a charge generating substance and a charge transporting layer having a charge transporting substance laminated on a conductive support, wherein the charge generating substance is C
In the X-ray diffraction spectrum by the u-Kα characteristic X-ray, the charge transport layer containing a titanyl phthalocyanine pigment having remarkable diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.5 ° and 28.7 °. Is a stereoisomeric mixture of bis (arylethenylphenyl) aniline compounds, and the maximum isomer component content in the stereoisomeric mixture is 40-9.
An organophotoreceptor containing 0% by mass of a charge transport material. 2. An organic photoreceptor having a charge generating layer containing a charge generating substance and a charge transporting layer having a charge transporting substance laminated on a conductive support, wherein the charge generating substance is C
In X-ray diffraction spectrum by u-Kα characteristic X-ray, Bragg angle (2θ ± 0.2 °) 7.5 °, 22.6 °, 24.
It contains a titanyl phthalocyanine pigment having prominent diffraction peaks at 5 °, 25.4 °, and 28.7 °, and a maximum diffraction peak at 7.5 ° or 28.7 °, and the charge transport layer contains bis. (Arylethenylphenyl) aniline-based compound stereoisomer mixture, characterized in that it contains a charge-transporting substance in which the content of the maximum isomer component in the stereoisomer mixture is 40 to 90% by mass. Organic photoconductor. 3. An organic photoreceptor having a charge generating layer containing a charge generating substance and a charge transporting layer having a charge transporting substance laminated on a conductive support, wherein the charge generating substance is C
In the X-ray diffraction spectrum by the u-Kα characteristic X-ray, the charge transport layer containing a titanyl phthalocyanine pigment having remarkable diffraction peaks at Bragg angles (2θ ± 0.2 °) of 7.5 ° and 28.7 °. Contains a bis (arylethenylphenyl) aniline compound, and the glass transition point Tgb of the binder resin of the charge transport layer and the glass transition point Tgl of the charge transport layer satisfy the following relationship. 100 ° C <Tgl <Tgb (Tgb, Tgl
(Unit: ° C) 4. An organic photoreceptor having a charge generating layer containing a charge generating substance and a charge transporting layer having a charge transporting substance laminated on a conductive support, wherein the charge generating substance is C
In X-ray diffraction spectrum by u-Kα characteristic X-ray, Bragg angle (2θ ± 0.2 °) 7.5 °, 22.6 °, 24.
It contains a titanyl phthalocyanine pigment having prominent diffraction peaks at 5 °, 25.4 °, and 28.7 °, and a maximum diffraction peak at 7.5 ° or 28.7 °, and the charge transport layer contains bis. An organophotoreceptor containing an (arylethenylphenyl) aniline compound, wherein the glass transition point Tgb of the binder resin of the charge transport layer and the glass transition point Tgl of the charge transport layer satisfy the following relationship. 100 ° C <Tgl <Tgb (Tgb, Tgl
(Unit: ° C) 5. The bis (arylethenylphenyl)
The organophotoreceptor according to claim 1, wherein the aniline compound is a compound represented by the following general formula (1). [Chemical 1] [In the general formula (1), R ¹ , R ² , R ³ , R ⁴ and R ⁵ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group. Ar ¹ represents a hydrogen atom or a substituted or unsubstituted aromatic group, and Ar ² represents a substituted or unsubstituted aromatic group. ] 6. The bis (arylethenylphenyl)
The aniline-based compound is a compound represented by the following general formula (2), wherein the organophotoreceptor according to any one of claims 1 to 4. [Chemical 2] [In the general formula (2), R ¹ , R ² , R ³ and R ⁴ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group. Ar ¹ is a hydrogen atom or a substituted or unsubstituted aromatic group,
Ar ² represents a substituted or unsubstituted aromatic group. ] 7. The bis (arylethenylphenyl)
The organophotoreceptor according to claim 1, wherein the aniline compound is a compound represented by the following general formula (3). [Chemical 3] [In the general formula (3), R ¹ , R ² , R ³ and R ⁴ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group. Ar ¹ is a hydrogen atom or a substituted or unsubstituted aromatic group,
Ar ² represents a substituted or unsubstituted aromatic group. ] 8. The bis (arylethenylphenyl)
The aniline-based compound is a compound represented by the following general formula (4), wherein the organophotoreceptor according to any one of claims 1 to 4. [Chemical 4] [In the general formula (4), R ¹ , R ² and R ³ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group.
Ar ¹ represents a hydrogen atom or a substituted or unsubstituted aromatic group, and Ar ² represents a substituted or unsubstituted aromatic group. ] 9. The bis (arylethenylphenyl)
The aniline-based compound is a compound represented by the following general formula (5), wherein the organophotoreceptor according to any one of claims 1 to 4. [Chemical 5] [In the general formula (5), R ¹ , R ² and R ³ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group.
Ar ¹ represents a hydrogen atom or a substituted or unsubstituted aromatic group, and Ar ² represents a substituted or unsubstituted aromatic group. ] 10. The bis (arylethenylphenyl) aniline-based compound is a compound represented by the following general formula (6):
The organic photoreceptor described in the item. [Chemical 6] [In the general formula (6), R ¹ and R ² are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group. Ar ¹
Represents a hydrogen atom or a substituted or unsubstituted aromatic group, and Ar ² represents a substituted or unsubstituted aromatic group. ] 11. The organophotoreceptor according to claim 5, wherein the substituted or unsubstituted aromatic group of Ar ¹ or Ar ² has the following general formula (7). . [Chemical 7] [In the general formula (7), R ^{6 to} R ¹⁷ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group, or 1 carbon atom.
To halogenated alkyl groups, halogen atoms or alkoxy groups having 1 to 4 carbon atoms. ] 12. The main binder resin of the charge transport layer is polycarbonate.
The organic photoreceptor according to any one of 1 to 11. 13. The organophotoreceptor according to claim 1, further comprising an intermediate layer between the conductive support and the charge generation layer. 14. The intermediate layer contains N-type semiconductive fine particles and a binder resin.
The organic photoreceptor described. 15. An image forming method, wherein an electrophotographic image is formed using the organic photoconductor according to claim 1. Description: 16. An image forming apparatus, wherein an electrophotographic image is formed by using the image forming method according to claim 15. 17. An organic photoconductor according to any one of claims 1 to 14, a charging device, an image exposing device, a developing device,
A process cartridge comprising at least one of a transfer device and a cleaning device, which is configured to be able to be taken in and out of an image forming apparatus.