JPH0534951A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To provide an electrophotographic sensitive body having improved wear resistance and satisfactory durability and undergoing no deterioration in the electrical characteristics. CONSTITUTION:When an electric charge generating layer and an electric charge transferring layer are successively laminated on a substrate to obtain an electrophotographic sensitive body, a blend of polycarbonate Z resin having repeating units represented by the formula with polyether imide resin, polyurethane resin or arom. polyester resin is used as a resin binder in the electric charge transferring layer.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an electrophotographic photoreceptor,
Specifically, it relates to an electrophotographic photoreceptor having excellent mechanical durability.

[0002]

2. Description of the Related Art In recent years, the number of copying machines and printers using organic photoconductors has increased. It is sensitive to a wide range of wavelengths from 400 to 800 nm and is more sensitive than inorganic photoconductors.
The manufacturing cost is low. However, comparing the mechanical durability of the a-Si and a-Se type photoreceptors of the inorganic photoreceptors, the photoreceptors are easily worn and the sensitivity is deteriorated. The cause of abrasion is that the surface of the photoreceptor is chemically and mechanically exposed to abrasion and scratches during the processes of charging, exposure, development, transfer and cleaning. The charge transfer layer forms a solid solution in which a charge transfer material is dissolved in a binder resin at a concentration of 30 to 50%. Therefore, the binder resin has no inherent strength, and it becomes a very brittle film, which is easily worn and easily scratched.

With respect to these problems, reduction of the friction coefficient of the surface of the photoconductor, reduction of surface energy, and as an antiwear agent,
Silicone-containing resin for the charge transfer layer (JP-A-61-219
049, 62-205357), a fluorine-containing resin (JP-A-50-23231, 61-116362, 61-20).
4633, 61-270768), or silicone resin fine particles, fluorine-containing resin fine particles (JP-A-63-65).
449), melamine resin fine particles (JP-A-60-1773).
49) has been proposed, but the compatibility between the charge transfer material and the binder resin is poor, the charge transfer layer becomes cloudy and opaque, sensitivity deterioration and image density unevenness occur, and the problem has not been solved. . Further, JP-A-60-168153 and JP-A-1-206348 propose a solution to the problem by increasing the molecular weight of the binder resin. However, a coating solution is required to apply an appropriate thickness of the charge transfer layer. The viscosity is high, and when bubbles are generated during stirring and circulation, bubbles adhere to the coating film, causing defects, and defoaming is difficult, resulting in a decrease in workability.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photosensitive member having improved abrasion resistance.

[0005]

According to the present invention, a polycarbonate Z resin having a repeating unit represented by the following chemical formula 1 in an electrophotographic photoreceptor in which a charge generation layer and a charge transfer layer are sequentially laminated on a support, An electrophotographic photoreceptor characterized in that a binder resin blended with a polyetherimide resin is used in the charge transfer layer.

[Chemical 1] In the electrophotographic photoreceptor in which a charge generation layer and a charge transfer layer are sequentially laminated on a support, a binder resin obtained by blending a polycarbonate Z resin having a repeating unit represented by the following chemical formula 1 and a polyurethane resin is charged. An electrophotographic photoreceptor characterized by being used as a moving layer

[Chemical 1] And a charge generating layer and a charge transfer layer are sequentially laminated on a support, and a polycarbonate Z resin having a repeating unit represented by the following chemical formula 1 and a repeating unit represented by the following chemical formula 2. An electrophotographic photoreceptor characterized in that a binder resin blended with an aromatic polyester resin is used in a charge transfer layer.

[Chemical 1]

[Chemical 2] Wherein, R _1, R _2: shows H, an alkyl group having 1 to 7 carbon atoms, or an aryl group. R ₁ and R ₂ may be taken together to form a ring. R ₃ , R ₄ , R ₅ , R ₆ : H, an alkyl group having 1 to 7 carbon atoms,
A phenyl group, a cycloalkyl group, or halogen is shown. And the aromatic polyester resin is a resin having a repeating unit represented by the following chemical formula 3. The electrophotographic photosensitive member is also provided.

[Chemical 3] In the formula, R ₃ , R ₄ , R ₆ : H, an alkyl group having 1 to 7 carbon atoms, a phenyl group, a cycloalkyl group or halogen is shown. n: an integer of 3 to 10

Polycarbonate Z resin is a high-strength polycarbonate A as an engineering plastic.
Although it is a resin that has better solution stability than resin, it has a slightly low tensile strength and elongation, but as described above, a solid solution with a charge transfer material concentration of 30 to 50% changes to a film that does not elongate and wear. A film that is easy to apply. The present inventors
It has been found that abrasion resistance can be improved by incorporating a polyetherimide resin, a polyurethane resin, or an aromatic polyester resin represented by the above chemical formula 2 into a charge transfer layer made of a polycarbonate Z resin.

Although the cause of this is not clear, it is considered that some force acts between the polycarbonate Z resin, these resins, and these charge transfer materials to reduce desorption (wear) from the layer. To be As described above, the tensile strength of the charge transfer layer is slightly stronger than that of the resin itself, but it does not extend and breaks. It is considered that this is because the charge transfer material interferes with the entanglement between the resin binders or the interaction of the resin to cause the resin desorption phenomenon (wear), but the polyetherimide resin, the polyurethane resin of the present invention, By incorporating the aromatic polyester resin, the desorption phenomenon is suppressed.

The polyetherimide resin is a resin having a high tensile strength, for example, a resin having a repeating unit represented by the following chemical formula 4, which is commercially available from Engineering Plastics under the trademark of Ultem, and is soluble in a halogen-based solvent.

[Chemical 4]

Although it is not clear whether the polyetherimide resin causes an interaction with the polycarbonate Z resin or the charge transfer material, it is not possible to remove the resin binder or the charge transfer material from the layer by using the polyetherimide resin. Less separation (wear).

The blend ratio (weight ratio) with the polycarbonate Z resin is polycarbonate Z resin: polyetherimide resin = 10: 0.1 or more, preferably 1
It is 0: 0.5-3. If it is less than 0.5, the effect is small, and if it is more than 3, the electric characteristics of the charge transfer layer are deteriorated.

The polyurethane resin is a resin which is rubbery and has a good adhesiveness and has a group having a hydrogen bonding force of NHC (= O) O-, and this functional group is -C = O of the polycarbonate Z resin. It is considered that hydrogen bonds with hydrogen strengthen the force between the polycarbonate resins and reduce desorption (wear). In fact, the alloy film of the polycarbonate Z resin and the polyurethane resin has a low breaking strength but a large elongation after passing the yield point. Conventionally, the charge transfer layer film also broke without a yield point, but the alloyed film has a yield point depending on the alloy ratio, and sticking occurs in the film. Polyurethane resin is a resin with relatively high crystallinity due to the presence of urethane bonds, and is a resin with high polarity that is difficult to be compatible with the charge transfer layer with low polarity, but an aromatic structure such as diphenylmethane in the main chain. In addition, the compatibility of those containing a long-chain alkyl structure in the polymer is controlled.

As such a polyurethane resin, conventionally known ones can be used, and specific examples thereof include polyester polyarethane and polyether polyurethane.

The blending ratio (weight) with the polycarbonate resin is 1 to 50 with respect to the polycarbonate Z resin.
%, And preferably 1 to 20%.

The aromatic polyester resin is a resin having a repeating unit represented by the following chemical formula 2,

[Chemical 2] Wherein, R _1, R _2: shows H, an alkyl group having 1 to 7 carbon atoms, or an aryl group. R ₁ and R ₂ may be taken together to form a ring. R ₃ , R ₄ , R ₅ , R ₆ : H, an alkyl group having 1 to 7 carbon atoms,
An aromatic polyester resin having a repeating unit represented by the following chemical formula 3 which represents a phenyl group, a cycloalkyl group, or a halogen is particularly preferable.

[Chemical 3] In the formula, R ₃ , R ₄ , R ₆ : H, an alkyl group having 1 to 7 carbon atoms, a phenyl group, a cycloalkyl group or halogen is shown. n: an integer of 3 to 10

These aromatic polyester resins have good compatibility with the charge transfer material and can be arbitrarily blended into the polycarbonate Z resin without making the charge transfer layer opaque. The molecular weight is 10,000 to 80,000, preferably 20,000 to 50,000, and the blend ratio (weight) is 5 to 90%, preferably 10 to 80% with respect to the polycarbonate Z resin.
These aromatic polyester resins are dissolved in, for example, an aqueous sodium hydroxide solution of a bisphenol compound, a small amount of hydrosulfite is added, and terephthalic acid chloride and isophthalic acid chloride and a methylene chloride solution of a trialkylamine as a catalyst are added under strong stirring at room temperature. The reaction was carried out for 1 hour, p-tertiary phenol was added and reacted for 1 hour, methylene chloride was added, the methylene chloride layer was separated, washed with distilled water acidic with acetic acid three times, and the methylene chloride layer was washed three times with distilled water. It can be manufactured by pouring into methanol after washing.

Table 1 below shows examples of repeating units of the aromatic polyester resin represented by Chemical Formula 2.

[Table 1- (1)]

[Table 1- (2)]

[Table 1- (3)]

[Table 1- (4)]

As the charge transfer material, oxazole derivatives and oxadiazole derivatives (Japanese Patent Laid-Open No. 52-13906).
5, 52-139066), imidazole derivatives, triphenylamine derivatives (Japanese Patent Application No. 1-778).
No. 39), a benzidine derivative (Japanese Patent Publication No. 58-32).
372), α-phenylstilbene derivatives (described in JP-A-57-73075), and hydrazone derivatives (JP-A-55-154955, 55-156954, 5).
5-52063, 56-81850, etc.), triphenylmethane derivative (Japanese Patent Publication No. 51-109).
83), anthracene derivatives (JP-A-51-9)
No. 4829), styryl derivatives (JP-A-56-2).
9245, 58-198043), carbazole derivatives (described in JP-A-58-58552), pyrene derivatives (described in Japanese Patent Application No. 2-94812), and the like.

As the charge generating material, C.I. I. No. 59
Condensed polycyclic quinone compounds such as 300 Vat Orange 3, C.I. I. No. Perylene compounds such as 38001,
And azo pigments having carbazole skeleton
-95033), an azo pigment having a styrylstilbene skeleton (described in JP-A-53-138229), an azo pigment having a triphenylamine skeleton (described in JP-A-53-132547), Azo pigments having a benzothiophene skeleton (JP-A-54-21728)
JP-A-54-12834), an azo pigment having an oxadiazole skeleton (described in JP-A-54-12742), an azo pigment having a fluorenone skeleton (described in JP-A-54-22834), and a bisstilbene skeleton. Azo pigments (described in JP-A-54-17733) and azo pigments having a distyryl oxadiazole skeleton (JP-A-54-54).
2129), an azo pigment having a distyrylcarbazole skeleton (described in JP-A-54-17734), a triazo pigment having a carbazole skeleton (described in JP-A-57-195767), and an anthraquinone skeleton. Examples thereof include azo pigments (described in JP-A-57-202545), metals, metal-free phthalocyanines, squarium dyes, and the like.

The photoreceptor is a resin binder, a charge transfer material,
The charge generation material is a conductive support made of aluminum, copper,
Vacuum evaporation, sputtering of the surfaces of electrically conductive metals and alloys such as nickel and stainless steel, and inorganic insulating substances such as glass and ceramics and organic insulating substances such as polyester, polyimide, phenol resin, nylon resin and paper. Drum shape, sheet that has been subjected to a conductive treatment by coating an electrically conductive substance such as aluminum, copper, nickel, stainless steel, carbon black, tin oxide, indium oxide, antimony oxide, and conductive titanium oxide by a method such as spray coating. It can be manufactured by melting and forming a photosensitive layer on a plate-shaped or plate-shaped material. The photosensitive layer is preferably a negative charging type photoreceptor in which a charge generation layer and a charge transfer layer are sequentially laminated, and the charge generation layer is composed of a ketone solvent such as methyl ethyl ketone or cyclohexanone, an ether solvent such as tetrahydrofuran or dioxane, or ethyl acetate. It is preferable to pulverize and disperse in a ball mill, a bead mill, a vibration mill or the like in a solvent such as an ester type, a halogen type such as dichloroethane or chlorobenzene, or an aromatic such as toluene or xylene to make the average particle size 0.3 μm or less. . At this time, a binder resin may be added, and examples of the resin binder include polyvinyl butyral, polyvinyl acetal, cellulose derivative, phenol resin, epoxy resin, acrylic polyol and the like. When the dispersion does not contain a binder resin, an intermediate layer is provided to prevent charge injection from the conductive support. Examples of the binder resin for the intermediate layer include polyamide, polyacrylic anilide, casein, vinyl chloride-vinyl acetate-maleic acid copolymer, and phenol resin.

As a coating method of the charge generating layer, a conventionally known method such as a dipping method, a spray method or a roll method is applied, and the film thickness is 0.05 to 5 μm, preferably 0.05 to 1 μm. The charge transfer layer comprises a blended resin and a charge transfer material in a weight ratio of 10: 5 to 12, preferably 10: 7 to 10, and a film thickness of 10 to 40 μm, preferably 20 to 30 μm.

[0021]

[Intermediate layer coating liquid]

Polyamide resin (CM-8000, manufactured by Toray Industries, Inc.) 10 g Methanol 120 g n-Butanol 120 g Then, the following charge generation layer coating liquid was applied onto the intermediate layer,
It was dried at 120 ° C. for 10 minutes to form a 0.3 μm charge generation layer. [Charge Generating Layer Coating Liquid] Compound of Chemical Formula 5 below 25 g Cyclohexanone 25 g Methyl ethyl ketone 25 g

[Chemical 5] After crushing and dispersing the above formulation in a ball mill for 72 hours,
Add 50 g of methyl ethyl ketone and disperse again for 3 hours.
The resulting mill base was let down with a mixed solvent of 25 g of cyclohexanone and 25 g of methyl ethyl ketone to obtain a coating liquid. Next, the following charge transfer layer coating liquid was applied onto the charge generation layer with a doctor blade and dried at 120 ° C. for 30 minutes to prepare a photoreceptor. Also, photoreceptors having different blending ratios of polycarbonate Z resin and polyetherimide resin were prepared. The ratio is shown in Table 2. [Charge Transfer Layer Coating Liquid] Compound of Chemical Formula 6 below 4.5 g Polycarbonate Z resin (manufactured by Teijin Chemicals) 4.2 g Polyetherimide resin (manufactured by Ultem, Engineering Plastics Co., Ltd.) 0.8 g Silicone oil (KF-50 Shin-Etsu) Chemical Co., Ltd.) 0.0005 g Dichloromethane 30 g 1,1,2-Trichloroethane 30 g

[Chemical 6]

Examples 2-4, Comparative Examples 1-2 Example 1 except that the polycarbonate Z resin and the polyetherimide resin were used in the blending ratios shown in Table 2 below.
A photoconductor was prepared in the same manner as in.

The electrophotographic photosensitive member produced as described above was used as an electrostatic copying paper tester [SP428, Kawaguchi Electric Co., Ltd.].
Mold] was used to evaluate the electrophotographic characteristics under the following conditions (measured in dynamic mode). First, for the sample -6K
Corona discharge of V is performed for 20 seconds to charge, the surface potential Vm (Volt) after 1 second and 20 seconds after charging is measured, and the surface potential Vo at that time is left for 20 seconds.
(Volt) is measured, and then 4.5 lux of white tungsten light is irradiated, the exposure amount E1 / 10 (lux · sec) required for V ₀ to be attenuated to 1/10, and irradiation 3
The surface potential V ₃₀ (Volt) after 0 seconds was measured and is shown in Table 2. The abrasion test was carried out by a rotary ablation tester manufactured by Toyo Seiki Co., Ltd., a wear wheel CS-10, and a load of 310 g for 2000 rotations.

[0024]

[Table 2] As described above, the abrasion resistance was improved by using the blend binder resin of polyetherimide. However, if the blend ratio of polyetherimide increases, the electrical characteristics deteriorate, and if the blend ratio is about 30% or more, it is difficult to apply to a copying machine. If it is less than 5%, the amount of wear tends to increase, which is not good.

Example 5 [Charge generation layer coating liquid]     5 parts of the compound of Chemical formula 7 below     Cyclohexanone 20 parts

[Chemical 7] Was pulverized and dispersed for 72 hours in a ball mill to obtain a charge generation layer coating liquid. As in Example 1, the above dispersion was provided with an intermediate layer and then coated with a doctor blade and dried to provide a 0.3 μm charge generation layer. [Charge Transfer Layer Coating Liquid] Compound of Chemical Formula 8 below 9 parts Polycarbonate Z resin (manufactured by Teijin Chemicals Ltd.) 8.5 parts Polyetherimide resin (manufactured by Engineering Plastics Co., Ltd. Ultem) 1.5 parts THF 80 parts Silicone oil ( KF-50 Shin-Etsu Chemical) 0.002 parts

[Chemical 8] Apply the above formulation with a doctor blade and dry it to 25μ
m charge transfer layer was provided. Results were measured as in Example _{1 Vm: 1580V, V 0:} 1280V, E1 / 2: 4.
05lux ・ sec, E1 / 10: 10.23lux ・
sec, V ₃₀ : 5 V, and wear film thickness: 1.0 μm.

Example 6 [Charge generation layer coating liquid]     4 parts of the compound of the following chemical formula 9     Cyclohexanone 25 parts

[Chemical 9] Was pulverized and dispersed for 72 hours in a ball mill to obtain a charge generation layer coating liquid. As in Example 1, the above-mentioned dispersion was coated with an intermediate layer by a doctor blade method, dried, and then dried.
A 1 μm charge generation layer was provided. The charge transfer layer forming liquid of Example 5 was applied onto this by a doctor blade method and dried to obtain 2
A 5μ charge transfer layer was provided. As a result of measurement in the same manner as in Example 1, Vm: 1280V, V ₀ : 1120V, E1 /
2: 0.85lux · sec, E1 / 10: 1.73l
It was ux · sec and V ₃₀ : 0. As described above, the blend of the polyetherimide resin in the charge transfer layer improves the abrasion resistance, and the blend of 20% or less with respect to the polycarbonate Z resin does not deteriorate the electrical characteristics.

Example 7 An aluminum plate having a thickness of 0.2 mm was coated with the following coating solution for the intermediate layer and coated with a doctor blade and dried at 120 ° C. for 10 minutes to form an intermediate layer having a thickness of 0.3 μm. . [Intermediate layer coating liquid] Polyamide resin (CM-8000, manufactured by Toray Industries, Inc.) 0.4 part Methanol 6 parts Butanol 3.6 parts Next, the following charge generating layer coating liquid was prepared and coated with a doctor blade, and 120 ° C. After drying for 10 minutes, a charge generation layer having a thickness of 0.3 μm was provided. [Charge Generating Layer Coating Liquid] 2.2 parts of the compound of Chemical Formula 5 2.2 parts of cyclohexanone was pulverized and dispersed in a ball mill for 72 hours, dispersed, 60 parts of cyclohexanone was added, and after again ball milling for 3 hours, cyclohexanone: methyl ethyl ketone = 1: A coating solution was prepared by letting down with 80 parts of a mixed solvent of 1 (weight ratio). Next, the following charge transfer layer liquid was prepared on the charge generation layer, coated with a doctor blade and dried at 120 ° C. for 20 minutes to give a film thickness of 25 μm.
m charge transfer layer was provided. [Charge Transfer Layer Coating Liquid] Compound of Chemical Formula 6 9 parts Polycarbonate Z resin (MY5,000 (manufactured by Teijin Chemicals)) 5 parts Polyurethane resin 5 parts (Miractran 265 manufactured by Nippon Polyurethane Company) THF 80 parts Silicone oil (KF -50 Shin-Etsu Chemical) 0.002 part

Examples 8-11, Comparative Examples 3-4 Photoreceptors were prepared in the same manner as in Example 7, except that the polycarbonate Z resin and the polyurethane resin were used in the blending ratios shown in Table 4 below.

Various characteristics of the electrophotographic photosensitive member prepared as described above were measured in the same manner as in Example 1, and the results are shown in Table 3 below.

[Table 3] As described above, probably because the compatibility between the polyurethane resin and the charge transfer material is poor, when the binder resin is blended in an equal amount, the charge transfer layer becomes opaque and the electrical characteristics are poor. Further, at 25%, the charge transfer layer was clouded.

Example 12 Example 7 was applied to an aluminum cylinder having a diameter of 80 mm and a diameter of 340 mm.
The intermediate layer of 0.3 μm and the charge generation layer of 0.3 μm shown in 1 above were applied by dip coating, and the charge transfer layer of Example 10 was applied by the dipping method and dried to provide 25 μm.

Comparative Example 5 Example 7 was applied to an aluminum cylinder having a diameter of 80 mm and a diameter of 340 mm.
0.3 μm by coating the intermediate layer liquid shown in 1 above with a dipping method and drying,
The charge generation layer liquid is applied by a dipping method and dried to form a charge generation layer 0.
On top of 3 μm, the charge transfer layer liquid of Comparative Example 3 was applied by a dipping method and dried to form a charge transfer layer of 25 μm. The above-mentioned Example 12 and Comparative Example 5 were used as a copying machine FT-482 manufactured by Ricoh Co., Ltd.
When mounted on No. 0, a sliding test including charging, exposure, development, and cleaning steps was performed for 1 million copies, and an abrasion resistance test was performed. As a result, Example 12 was 1.5 μm, and Comparative Example 5 was 7 μm.
The m charge transfer layer was worn. From the above, the abrasion resistance is improved by blending the polyurethane resin in the polycarbonate Z resin.

Example 13 [Charge generation layer coating liquid] The compound of the above Chemical formula 7 (5 parts) and cyclohexanone (20 parts) were pulverized and dispersed in a ball mill for 72 hours to obtain a charge generation layer coating liquid. Similar to Example 7, the dispersion was coated with a doctor blade on the intermediate layer and dried to 0.3 μm.
m charge generation layer was provided. [Charge Transfer Layer Coating Liquid] Compound of Chemical Formula 9 9 parts Polycarbonate Z resin (manufactured by Teijin Chemicals Ltd.) 8.5 parts Polyurethane resin (mylactone 265 manufactured by Nippon Polyurethane Co., Ltd.) 1.5 parts THF 80 parts Silicone oil (KF- 50 Shin-Etsu Chemical) 0.002 parts The above prescription liquid is coated with a doctor blade and dried to 25 μm.
m charge transfer layer was provided. Results measured in the same manner as in Example 7 Vm: 1500V, V ₀ : 1200V, E1 / 2: 3.
85lux ・ sec, E1 / 10: 9.48lux ・ s
ec, V ₃₀ : 3 V, and wear film thickness: 1.0 μm.

Example 14 [Charge generating layer coating liquid] A compound of the following chemical formula 4 4 parts cyclohexanone 25 parts were pulverized and dispersed by a ball mill for 72 hours to obtain a charge generating layer coating liquid. This was coated with an intermediate layer in the same manner as in Example 7 by the doctor blade method and dried to give 0.1 μm.
m charge generation layer was provided. The charge transfer layer-forming liquid of Example 13 was applied onto this by a doctor blade method and dried to 25
A μ charge transfer layer was provided. Vm: 1310V, V ₀ : 1050V, E1 / 2: 0.
74lux · sec, E1 / 10: 1.53lux · s
ec, V ₃₀ : 0 As described above, the blend of the polyurethane resin in the charge transfer layer improves the abrasion resistance, and the blend of 20% or less with respect to the polycarbonate Z resin does not deteriorate the electrical characteristics.

Example 15 An aluminum cylinder having a stroke of 80 mm and a stroke of 340 mm was coated with the following intermediate layer coating solution by a dipping method to obtain 120
After drying at 10 ° C. for 10 minutes, an intermediate layer having a film thickness of 0.3 μm was provided. [Intermediate layer coating liquid] Polyamide resin (CM-8000, manufactured by Toray Industries, Inc.) 4 parts Methanol 60 parts Butanol 36 parts Then, the following charge generation layer coating liquid is prepared and applied by a dipping method,
After drying at 120 ° C. for 10 minutes, a charge generation layer having a thickness of 0.3 μm was provided. [Charge Generating Layer Coating Liquid] 22 parts of the compound of Chemical formula 5 440 parts of cyclohexanone were pulverized and dispersed in a ball mill for 72 hours, 600 parts of cyclohexanone was added, and after ball milling again for 3 hours, cyclohexanone: methyl ethyl ketone = 1: 1 weight A coating solution was prepared by letting down with 800 parts of a mixed solvent having a specific ratio. Next, the following charge transfer layer liquid was prepared on the charge generation layer and applied by a dipping method and dried at 120 ° C. for 20 minutes to form a charge transfer layer having a film thickness of 23 μm. [Charge Transfer Layer Coating Liquid] Polycarbonate Z resin (manufactured by Teijin Chemicals Co., Ltd.) 50 parts Aromatic polyester resin having a repeating unit represented by the following chemical formula 50 50 parts Compound of the following chemical formula 90 90 parts THF 500 parts Silicone oil (KF- 50 manufactured by Shin-Etsu Silicone Co., Ltd.) 0.1 part

[Chemical 10]

[Chemical 11]

Examples 16 to 27 As in Example 15, the intermediate layer and the charge generation layer were provided, and the polyester resin shown in Table 4 was used. It was made.

Comparative Example 6 As in Example 15, an intermediate layer and a charge generation layer were provided, and the following charge transfer layer solution was applied by a dipping method and dried at 120 ° C. for 20 minutes to form a 23 μm charge transfer layer. Provided. [Charge Transfer Layer Coating Liquid] Polycarbonate Z resin (manufactured by Teijin Chemicals Ltd.) 100 parts Compound of formula 11 90 parts THF 500 parts Silicone oil (KF-50 manufactured by Shin-Etsu Silicone Co., Ltd.) 0.1 part Comparative Example 7 Example 15 Similarly to the above, an intermediate layer and a charge generating layer were provided, and then the following charge transfer layer liquid was applied by a dipping method and dried at 120 ° C. for 20 minutes to provide a 23 μm charge transfer layer. [Charge Transfer Layer Coating Liquid] Aromatic polyester resin having a repeating unit represented by the following chemical formula 12 100 parts Compound of the chemical formula 11 90 parts Silicone oil 0.05 parts THF 500 parts

[Chemical 12]

The photoconductors obtained in Examples 15 to 27 and Comparative Examples 6 and 7 were mounted in the apparatus described in JP-A-60-100167 and rotated at 1000 rpm to obtain a negative 6K in the dark.
The potential Vm when the voltage of V was discharged and applied for 20 seconds was determined, and then the discharge was stopped and dark decay was performed for 20 seconds, and the potential Vo at that time was measured. In addition, 26 lu of tungsten light
The amount of light of x, which is radiated for 20 seconds with a slit width of 6 mm, is halved from Vo by E1 / 2, and the amount that becomes 1/10 is E1 / 10.
Was asked for sensitivity. The potential after 20 seconds was set to Vr. The results are shown in Table 4. Further, these photoconductors were mounted on FT-4820 manufactured by Ricoh Co., Ltd., and a durability test of 10,000 sheets was conducted. The results are shown in Table 5. The initial dark area potential (VD) was set to 800V and the light area potential (VL) to 80V. The results are shown in Table 5.

[0038]

[Table 4-1]

[Table 4-2]

[Table 4-3]

[Table 4-4]

[Table 4-5]

[0039]

[Table 5] As described above, the photoconductor of the present invention is a photoconductor with a small amount of wear and high durability.

[0040]

The electrophotographic photoreceptor of the present invention comprises a polycarbonate Z resin as a binder resin for the charge transfer layer,
Since it uses a binder resin that is a blend of either a polyetherimide resin, a polyurethane resin or an aromatic polyester resin, it has improved wear resistance, good durability, and has the effect of not lowering the electrical characteristics. is there.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshiaki Kawasaki             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh

Claims (4)

[Claims] 1. An electrophotographic photoreceptor in which a charge generation layer and a charge transfer layer are sequentially laminated on a support, and a binder resin obtained by blending a polycarbonate Z resin having a repeating unit represented by the following chemical formula 1 and a polyetherimide resin. An electrophotographic photoreceptor characterized in that is used as a charge transfer layer. [Chemical 1] 2. An electrophotographic photosensitive member comprising a support and a charge generation layer and a charge transfer layer laminated in this order, and a binder resin prepared by blending a polycarbonate Z resin having a repeating unit represented by the following chemical formula 1 and a polyurethane resin. An electrophotographic photoreceptor characterized by being used as a moving layer. [Chemical 1] 3. An electrophotographic photosensitive member comprising a support, on which a charge generation layer and a charge transfer layer are sequentially laminated, having a polycarbonate Z resin having a repeating unit represented by the following chemical formula 1 and a repeating unit represented by the following chemical formula 2. An electrophotographic photoreceptor characterized in that a binder resin blended with an aromatic polyester resin is used in a charge transfer layer. [Chemical 1] [Chemical 2] Wherein, R _1, R _2: shows H, an alkyl group having 1 to 7 carbon atoms, or an aryl group. R ₁ and R ₂ may be taken together to form a ring. R ₃ , R ₄ , R ₅ , R ₆ : H, an alkyl group having 1 to 7 carbon atoms,
A phenyl group, a cycloalkyl group, or halogen is shown. 4. The aromatic polyester resin is represented by the following chemical formula 3.
The electrophotographic photosensitive member according to claim 3, which is a resin having a repeating unit represented by: [Chemical 3] In the formula, R ₃ , R ₄ , R ₆ : H, an alkyl group having 1 to 7 carbon atoms, a phenyl group, a cycloalkyl group or halogen is shown. n: an integer of 3 to 10