JPH1078672A - Electrophotographic photoreceptor, process cartridge and electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily produce an electrophotographic photoreceptor having superior solvent cracking resistance, improved electricity resistance and slight photomemory by forming a surface layer contg. a polymer having specified constituent units. SOLUTION: This electrophotographic photoreceptor has a surface layer contg. a polymer having constituent units represented by the formula, wherein each of R1 -R12 is H, halogen such as F or Cl, optionally substd. alkyl such as methyl, ethyl or propyl or optionally substd. aryl such as phenyl or naphthyl and each of (m) and (n) is an integer of 1-10. Since central carbon in the polymer has been modified with phenyl groups, the cleavage of bonding by AC electrification can be prevented, and the polymer can impart durability without deteriorating electrophotographic characteristics because of its three-dimensional network structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member, a process cartridge having the electrophotographic photosensitive member, and an electrophotographic apparatus. More specifically, the present invention relates to an electrophotographic photosensitive member having a surface layer containing a specific resin, and The present invention relates to a process cartridge having an electrophotographic photosensitive member and an electrophotographic apparatus.

[0002]

2. Description of the Related Art An electrophotographic method is disclosed in U.S. Pat.
As shown in JP-A No. 1 (1993), a photoconductive material comprising a support coated with an insulating substance is used in which the electric resistance changes in accordance with the amount of irradiation received during image exposure, and in a dark place. The basic characteristics required of an electrophotographic photoreceptor using this photoconductive material are (1) that it can be charged to an appropriate potential in a dark place, (2) that the potential is less dissipated in a dark place, and (3) And (3) quickly dissipating the charge by light irradiation.

[0003] Conventionally, selenium,
Inorganic photoreceptors having a photosensitive layer mainly containing an inorganic photoconductive compound such as zinc oxide and cadmium sulfide have been widely used. However, these satisfies the conditions (1) to (3), but are not necessarily satisfactory in thermal stability, moisture resistance, durability and productivity.

In order to overcome the disadvantages of inorganic photoconductors, electrophotographic photoconductors containing various organic photoconductive compounds as main components have been actively developed in recent years. For example, US Pat.
No. 851 describes a photoreceptor having a charge transporting layer containing triallylpyrazolin, and US Pat. No. 3,871,880 discloses a photogenerating layer comprising a derivative of perylene pigment and 3
Photoreceptors comprising a charge transport layer comprising a condensate of propylene and formaldehyde are known.

Further, the organic photoconductive compound can freely select the photosensitive wavelength range of the electrophotographic photosensitive member depending on the compound.
JP-A Nos. 2754 and 56-167759 disclose substances exhibiting high sensitivity in the visible region, and JP-A-57-19576 and JP-A-61-22.
No. 8453 discloses a compound having sensitivity up to the infrared region.

[0006] Of these materials, those exhibiting sensitivity in the infrared region are used in laser beam printers (hereinafter abbreviated as LBPs) and LED printers, which have been remarkably advanced in recent years, and the demand frequency thereof is increasing.

Electrophotographic photoreceptors using these organic photoconductive compounds are used as function-separated type photoreceptors in which a charge transport layer and a charge generation layer are laminated in order to satisfy both electrical and mechanical properties. In many cases. On the other hand, it is needless to say that the electrophotographic photoreceptor is required to have sensitivity, electrical characteristics, and even optical characteristics according to the electrophotographic process applied.

Particularly, in the case of an electrophotographic photoreceptor that is used repeatedly, an external electric or mechanical force such as corona or direct charging, image exposure, toner development, transfer step and surface cleaning is directly applied to the electrophotographic photoreceptor surface. For,
Durability against them is also required.

Specifically, electrical deterioration due to ozone and nitrogen oxides during charging, mechanical deterioration in which the surface is worn or scratched due to discharge during charging, and rubbing of the cleaning member, and electrical deterioration Durability is required.

[0010] The electrical deterioration is particularly problematic in that carriers stay in a portion irradiated with light and a potential difference is generated between the portion not irradiated with light and a photo memory.

[0011] Unlike an inorganic photoreceptor, an organic photoreceptor, which is often soft in material, is inferior in durability against mechanical deterioration and is particularly demanded to improve durability.

Various attempts have been made to satisfy the durability characteristics required for the photoreceptor as described above.

As a resin often used for the surface layer and having good abrasion and electric properties, a polycarbonate resin having bisphenol A as a skeleton has been attracting attention. However, not all of the above-mentioned problems can be solved, and the following problems cannot be solved. It has such problems.

(1) It has poor solubility and shows good solubility only in a part of halogenated aliphatic hydrocarbons such as dichloromethane and 1,2-dichloroethane. In addition, since these solvents have a low boiling point, they have low solubility. When a photoreceptor is manufactured using a coating solution prepared with the above solvent, the coated surface is likely to be whitened. It also takes time to control the solid content of the coating liquid.

(2) Solvents other than halogenated aliphatic hydrocarbons are partially soluble in tetrahydrafuran, dioxane, cyclohexanone or a mixed solvent thereof, but the solution gels in a few days. Inferior aging,
It is not suitable for photoconductor production.

(3) Further, even if the above formulas (1) and (2) are improved, solvent cracks are liable to occur in the polycarbonate resin having bisphenol A as a skeleton.

(4) In addition, in the case of a conventional polycarbonate resin, the coating formed of the resin does not have lubricity, so that the photosensitive member is easily damaged, and the cleaning setting for reducing the abrasion amount of the electrophotographic photosensitive member is not sufficient. In some cases, an image defect such as toner fusion occurs, or cleaning failure occurs due to early deterioration of the cleaning blade.

For the solution stability mentioned in the above (1) and (2), use of a polycarbonate Z resin having a bulky cyclohexylene group as a structural unit of the polymer, or copolymerization with bisphenol Z or bisphenol C, etc. Has been solved by

Solvent cracks can also be solved by using a silicone-modified polycarbonate or an ether-modified polycarbonate, as disclosed in JP-A-6-51544 and JP-A-6-75415. . However, compared to conventional polycarbonate resins, these modified polycarbonates have a structure that has flexibility against internal stress in the polymer in order to prevent solvent cracks, and as a result, the mechanical There was a disadvantage that the strength was reduced.

Further, in recent years, a direct charging system disclosed in JP-A-57-17826 and JP-A-58-40566, in which a voltage is applied directly to a charging member and a charge is applied to an electrophotographic photosensitive member. Is becoming mainstream.

This is a method in which a roller-shaped charging member made of a conductive rubber or the like is brought into direct contact with an electrophotographic photosensitive member to apply an electric charge. The scorotron generates a significantly smaller amount of ozone than a scorotron or the like. While about 80% of the current flowing through the charger flows through the shield, it is wasted, whereas direct charging has the advantage that it is very economical without this waste.

However, direct charging has a disadvantage that charging stability is very poor because of charging by discharge according to Paschen's rule. As a countermeasure, a so-called AC / DC charging method in which an AC voltage is superimposed on a DC voltage has been devised (Japanese Patent Application Laid-Open No. 63-149668).

Although this charging method has improved the stability during charging, the amount of discharge on the surface of the electrophotographic photosensitive member is greatly increased due to the superposition of AC, so that the amount of scraping of the electrophotographic photosensitive member increases. A new drawback has arisen, requiring not only mechanical strength but also electrical strength.

[0024]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of having a conventional polycarbonate resin as a surface layer, to have excellent solvent crack resistance without impairing mechanical strength, and An object of the present invention is to provide an electrophotographic photoreceptor which has good electric resistance due to direct charging, has less photo memory, is easy to manufacture, and a process cartridge and an electrophotographic apparatus having the electrophotographic photoreceptor.

[0025]

That is, the present invention relates to an electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the surface layer of the electrophotographic photosensitive member has the following formula (1) or (2):
An electrophotographic photoreceptor comprising a polymer having a structural unit represented by the formula:

[0026]

Embedded image (Wherein, R _{1 to} R _{12 each} represent a hydrogen atom, a halogen atom, an alkyl group or an aryl group which may be substituted, and m and n each represent an integer of 1 to 10)

[0027]

Embedded image (In the formula, X represents a single bond, -O-, -S-, or an optionally substituted alkylidene group or a cycloalkylidene group, and at least one of R _{21 to} R ₂₈ is-(CH
₂ ) _p -CH = CH ₂ (p is an integer of 2 or more),
Those other than the above groups represent a hydrogen atom, a halogen atom, and an alkyl group or an aryl group which may be substituted. R
₂₉ to R ₃₂ represents a hydrogen atom, a halogen atom, each of which may be substituted alkyl group or an aryl group. )

[0028]

DETAILED DESCRIPTION OF THE INVENTION In the above formulas (1) and (2), halogen atoms include fluorine, chlorine and bromine atoms, and alkyl groups include methyl, ethyl and propyl. Aryl groups include phenyl, naphthyl and anthryl groups; alkylidene groups include ethylidene group, propylidene group and i-butylidene group; cycloalkylidene groups include cyclopentylidene group and cyclohexylidene group. Examples thereof include a den group and a cyclooctylidene group. Examples of the substituent which these may have include the above-described halogen atom, alkyl group, and aryl group.

Specific examples of the structural units represented by the above formulas (1) and (2) are shown in Tables 1 and 2, but are not limited thereto.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

[0033]

[Table 4]

[0034]

[Table 5]

[0035]

[Table 6]

[0036]

[Table 7]

Preferred examples of the structural unit represented by the formula (1) include structural unit examples 1-1, 1-2 and 1-15, and the structural unit example 1-1 is particularly preferable.

Preferred examples of the structural unit represented by the formula (2) include structural unit examples 2-1, 2-2, 2-3, 2-4,
2-5 and 2-10, in particular, structural unit examples 2-2.
And 2-5 are preferred.

Formula (1) used in the present invention,
The polymer having the constitutional unit represented by (2) is prepared by adding a mixture of terephthalic acid chloride and isophthalic acid chloride to a bisphenol represented by the following formulas (3) and (4) under alkali in order to increase the solubility. It can be synthesized by performing interfacial polymerization by stirring in a solvent / water system.

[0040]

Embedded image (Wherein, R _{1 to} R _{8 each} represent a hydrogen atom, a halogen atom, an alkyl group or an aryl group which may be substituted, and m and n each represent an integer of 1 to 10)

[0041]

Embedded image (In the formula, X represents a single bond, -O-, -S-, or an optionally substituted alkylidene group or a cycloalkylidene group, and at least one of R _{21 to} R ₂₈ is-(CH
₂ ) _p -CH = CH ₂ (p is an integer of 2 or more),
Those other than the above groups represent a hydrogen atom, a halogen atom, and an alkyl group or an aryl group which may be substituted. In the electrophotographic photoreceptor of the present invention, a polymer composed of one kind of the structural unit represented by the formula (1) or (2) may be a polymer composed of two or more kinds of the structural unit represented by the formula (1) or (2). Can also be used.

The ratio between terephthalic acid chloride and isophthalic acid chloride is determined in consideration of the solubility of the polymer, and is not defined. However, any chloride is 30 mol
Care must be taken when the content is less than 10% because the solubility of the synthesized polymer is extremely reduced. Usually, it is preferable to synthesize at a ratio of 1/1.

Further, a copolymer with other general bisphenols such as bisphenol Z, bisphenol A, bisphenol C and bisphenol AF may be prepared in consideration of solubility during polymerization. However, in this case, the structural unit represented by the formula (1) is preferably present in an amount of 5 to 100 mol%, more preferably 50 to 100 mol%, of all the polymers.
1%. Further, it is preferable that the structural unit represented by the formula (2) is present in an amount of 5 to 100 mol% of the entire polymer,
More preferably, it is 50 to 100 mol%.

The electrophotographic photoreceptor of the present invention containing a polymer having the structural units represented by the formulas (1) and (2) is particularly suitable for solvent crack resistance, mechanical strength, electric resistance in AC charging, and memory. It has excellent characteristics and has both of them.

The polymer having the structural unit represented by the formula (1) can be obtained by modifying the central carbon with a phenyl group.
This prevents the bond from being broken by charging. And an allyl group or the like disposed on the phenyl group [(CH ₂ ) _{m or n} CH =
[CH ₂ , m, n = 1 to 10] is heat-condensed during the formation of the electrophotographic photosensitive member to form a three-dimensional network, thereby having durability without impairing the electrophotographic characteristics.

With respect to the solvent cracking resistance, an allyl group substituted by a phenyl group or the like is heated and condensed during the formation of an electrophotographic photosensitive member to form a three-dimensional network structure. It is presumed that cracks hardly occur to maintain the internal stress and the solvent crack resistance is excellent.

The mechanical strength is enhanced by the three-dimensional network structure described above, and the same is performed with a polycarbonate resin, which is disclosed in JP-A-5-323630 and the like.

Regarding the electric resistance property in AC charging,
By surrounding the central carbon atom with a phenyl group, the generation of radical species due to AC charging at this site is suppressed, and the bond is protected from attack by the generated radical species. Presumed. In addition, since the three-dimensional network structure is unlikely to cause a sharp decrease in film strength even when molecular breakage due to electrical deterioration occurs, it is estimated that the film has excellent electric resistance characteristics in AC charging. Further, as compared with the carbonate bond, the ester bond of the aryl group is more resistant to current caused by AC charging, and the electric resistance is particularly improved. Although the reason for this has not been confirmed, it is assumed that the carbonate bond has a large dipole moment due to oxygen atoms on both sides of the carboxy group and is weak against electric energy. Presumed.

Regarding the memory characteristics, it is presumed that the adoption of an aryl ester structure and the introduction of a phenyl group in which an allyl group is substituted for a central carbon atom improves the matching with the charge transporting material, resulting in excellent memory characteristics.

Further, it has a structural unit represented by the formula (2).
Is a polymer having-(CH _Two)_p-CH = CH
_TwoHaving a group represented by
It has a three-dimensional mesh and durability
You. When p is 1, it is an allyl group, but it binds from the molecular model
Crosslinking due to too close double bond between aromatic ring and allyl group
There are not many opportunities. Therefore, a double bond and an aromatic ring
The cross-link density may increase by increasing the distance of
This led to the present invention. The number of p is from 2 to 100
It can be preferably used, but optimally 4 to 20 is appropriate polymerization
Easy to get meetings. If p is 2-3, the overall level is higher
Although it is close to an allyl group, if it is 20 or more,
Fin chains become too long and strength after curing tends to decrease
is there.

It is presumed that the three-dimensional structure maintains the internal stress and does not cause cracks even when a chemical causing a solvent crack enters.

Regarding the mechanical strength, the mechanical strength is strengthened by the three-dimensional network structure, and the same is performed with a polycarbonate resin, which is disclosed in JP-A-5-323630 and the like.

Regarding the electric resistance, even if molecular breakage due to electrical degradation occurs due to the three-dimensional structure, a sharp decrease in film strength is unlikely to occur, and the ester bond of the aryl group is more resistant to the current due to AC charging than the carbonate bond. In particular, the electric resistance has been improved. The reason for this is presumed to be that an unidentified carbonate bond has a large dipole moment due to oxygen atoms on both sides of the carboxy group and is weak against electric energy.

Further, it has been found that the adoption of the aryl ester structure improves the matching of the charge transporting material and improves the memory characteristics.

As described above, an increase in _{p in} — (CH ₂ ) _p —CH ＝ CH _{2 in} the structural unit represented by the formula (2) means that the molecular side chain is elongated. As a result, it was found that a stronger three-dimensional network structure was obtained, and the mechanical strength and the charging characteristics in AC charging were further improved.

Further, since the three-dimensional network structure was strengthened, the charging ability was improved, and the charge was uniformly charged on the photosensitive member. Equation (2) shown configuration in units of the - (CH ₂₎ when p of _p -CH = CH ₂ is to charge as with those not three-dimensional in the case of 1, the initial charging becomes uneven It has been found that this is liable to cause so-called drum ghost. However, when p of R ₁ is 2 or more in the structural unit represented by the formula (2), it is found that the photosensitive member surface is uniformly charged and image defects such as drum ghost do not occur as described above. Was.

Hereinafter, the configuration of the electrophotographic photosensitive member used in the present invention will be described.

The electrophotographic photoreceptor of the present invention may be a single-layer type in which the photosensitive layer contains a charge transporting material and a charge generating material in the same layer, or a laminated type in which a charge transporting layer and a charge generating layer are separated. Although good, the laminated type is preferable in terms of electrophotographic characteristics.

The conductive substrate to be used may be any one having conductivity, such as metal such as aluminum and stainless steel, or a metal provided with a conductive layer, paper and plastic. Is mentioned.

When an image input such as LBP is a laser beam, a conductive layer may be provided for the purpose of preventing interference fringes due to scattering or covering a scratch on the support. This can be formed by dispersing conductive powder such as carbon black and metal particles in a binder resin. The thickness of the conductive layer is 5
４０40 μm is preferable, and more preferably 10-30 μm
It is.

An intermediate layer having an adhesive function is provided thereon. Examples of the material for the intermediate layer include polyamide, polyvinyl alcohol, polyethylene oxide, ethyl cellulose, casein, polyurethane, and polyether urethane. These are applied by dissolving in an appropriate solvent.
The thickness of the intermediate layer is preferably from 0.05 to 5 μm, more preferably from 0.3 to 1 μm.

The charge generation layer is formed on the intermediate layer.
Examples of the charge generation material used in the present invention include selenium-tellurium, pyrylium, thiapyrylium dyes, phthalocyanine, anthantrone, dibenzapyrene quinone, trisazo, cyanine, disazo, monoazo, indigo, quinacridone, and asymmetric quinocyanine pigments. Can be In the case of the function separation type, the charge generation layer is obtained by mixing the charge generation material with a binder resin and a solvent in an amount of 0.3 to 4 times the amount of a homogenizer, an ultrasonic dispersion, a ball mill, a vibration ball mill, a sand mill, an attritor, a roll mill and a liquid collision type Disperse well by a method such as a high-speed disperser, apply the dispersion,
It is formed by drying. The thickness of the charge generation layer is preferably 5 μm or less, more preferably 0.1 to 2 μm.

The charge transport layer is formed by applying and drying a coating material in which a charge transport material and a binder resin containing a polymer used in the present invention are dissolved in a solvent. Examples of the charge transport material used include a triarylamine compound, a hydrazone compound, a stilbene compound, a pyrazoline compound, an oxazole compound, a triallylmethane compound, and a thiazole compound.

These are combined with 0.5 to 2 times the amount of the binder resin, applied and dried to form a charge transport layer. The thickness of the charge transport layer is preferably from 5 to 40 μm, more preferably from 15 to 30 μm.

FIG. 1 shows a schematic configuration of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention.

In FIG. 1, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is driven to rotate around a shaft 2 in a direction of an arrow at a predetermined peripheral speed. The photoreceptor 1 rotates during the rotation process.
The peripheral surface is uniformly charged with a predetermined positive or negative potential by the primary charging means 3, and then receives image exposure light 4 from an image exposure means (not shown) such as slit exposure or laser beam scanning exposure. Thus, an electrostatic latent image is sequentially formed on the peripheral surface of the photoconductor 1.

The formed electrostatic latent image is then developed.
The toner-developed image developed by the toner image is transferred from a paper supply unit (not shown) between the photoconductor 1 and the transfer unit 6 in synchronization with the rotation of the photoconductor 1 and fed to a transfer material 7 fed therefrom. The image is sequentially transferred by the transfer unit 6.

The transfer material 7 having undergone the image transfer is separated from the surface of the photoreceptor, introduced into the image fixing means 8 and subjected to image fixing to be printed out as a copy out of the apparatus.

The surface of the photoreceptor 1 after the image is transferred is cleaned by removing the untransferred toner by the cleaning means 9, and is further cleaned by a pre-exposure light 10 from a pre-exposure means (not shown).
Is used for image formation repeatedly after the charge removal processing. When the primary charging unit 3 is a contact charging unit using a charging roller or the like, the pre-exposure is not necessarily required.

In the present invention, of the above-mentioned components such as the electrophotographic photosensitive member 1, the primary charging means 3, the developing means 5 and the cleaning means 9, a plurality of components are integrally connected as a process cartridge. This process cartridge may be configured to be detachable from a main body of an electrophotographic apparatus such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 3, the developing unit 5, and the cleaning unit 9 is integrally supported together with the photoreceptor 1 to form a cartridge, which can be attached to and detached from the apparatus main body using a guide unit such as a rail 12 of the apparatus main body. Process cartridge 1
It can be 1.

When the electrophotographic apparatus is a copying machine or a printer, the image exposure light 4 is reflected or transmitted from the original, or the original is read by a sensor and is converted into a signal. Laser beam scanning,
Light emitted by driving the LED array, driving the liquid crystal shutter array, and the like.

On the other hand, when used as a facsimile printer, the image exposure light 4 becomes exposure light for printing received data. FIG. 2 is a block diagram showing an example of this case.

The controller 14 controls the image reading unit 13 and the printer 22. The entire controller 14 is controlled by the CPU 20. The read data from the image reading unit 13 is transmitted to the partner station through the transmission circuit 16. Data received from the partner station is sent to the printer 22 through the receiving circuit 15. Predetermined image data is stored in the image memory. The printer controller 21 controls the printer 22. 17 is a telephone.

The image received from the line 18 (image information from a remote terminal connected via the line) is demodulated by the receiving circuit 15, then the image information is decoded by the CPU 20, and is sequentially stored in the image memory 19. Is done. When the image of at least one page is stored in the memory 19, the CPU 20 performs image recording of the page. The CPU 20 reads out the image information of one page from the image memory 19, and Sends out image information. The printer controller 21
When receiving one page of image information from the CPU 20, the printer 22 is controlled to record image information of the page. The CPU 20 is receiving the next page during recording by the printer 22.

Thus, the reception and recording of the image are performed.

The electrophotographic photosensitive member of the present invention can be used not only for an electrophotographic copying machine but also for a laser beam printer,
It can be widely used in electrophotographic applications such as RT printers, LED printers, liquid crystal printers, and laser plate making.

A description will be given below in accordance with embodiments. The middle part in the examples indicates parts by weight.

Example 1 A 30φ, 254 mm aluminum cylinder was used as a support, and a coating composed of the following materials was applied on the support by a dip coating method, and was thermally cured at 140 ° C. for 30 minutes to 15 μm. Was formed.

Conductive pigment: SnO ₂ coated barium sulfate 10 parts Resistance adjusting pigment: titanium oxide 2 parts Binder resin: phenol resin 6 parts Leveling material: silicone oil 0.001 parts Solvent: methanol, methoxypropanol 0.2 / 0.8 20 parts

Next, a solution obtained by dissolving 3 parts of N-methoxymethylated nylon and 3 parts of copolymerized nylon in a mixed solvent of 65 parts of methanol and 30 parts of n-butanol was applied thereon by dip coating to form a 0.5 μm Was formed.

Next, oxytitanium phthalocyanine (TiOPc) having strong peaks at 9.0 °, 14.2 °, 23.9 ° and 27.1 ° at Bragg angles 2θ ± 0.2 ° of CuKα characteristic X-ray diffraction. ) 4 parts and 2 parts of polyvinyl butyral (trade name: Eslec BM2, manufactured by Sekisui Chemical) and 60 parts of cyclohexanone were dispersed for 4 hours by a sand mill using φ1 mm glass beads, and then 100 parts of ethyl acetate was added to form a charge generating layer. A dispersion was prepared.
This was applied by a dip coating method to form a 0.3 μm charge generation layer.

Next, 9 parts of an amine compound having the following structural formula:

[0083]

Embedded image 1 part of amine compound of the following structural formula

[0084]

Embedded image And Example No. 3 in Table 3. 10 parts of the polymer shown in 1 were dissolved in a mixed solvent of 30 parts of monochlorobenzene and 70 parts of dichloromethane. This paint was applied by a dip coating method and dried at 120 ° C. for 2 hours to form a 25 μm charge transport layer.

The polymer used in this example was 1,1-bis [4 (2-propenyl) phenyl] -1,1-bis (4
-Hydroxyphenyl) methane (10 mmol), sodium hydroxide (3 g) and tributylbenzylammonium chloride (0.125 g) were dissolved in water (50 ml) with stirring and dissolved separately. The methylene chloride layer was added under strong stirring and stirred for 3 hours. After 3 hours, 20 mmol of acetic acid was added, the methylene chloride layer was separated, washed with water until the methylene chloride layer became neutral, then dropped into methanol, and the polymer was taken out and filtered. Table 3 shows the molecular weight measured by gel permeation chromatography. The yield is 70%.

Next, evaluation will be described.

The device is a Hewlett-Packard LBP
"Laser jet 4plus" (process speed 7
1 mm / sec). In the remodeling, primary charging was controlled by constant current control and constant voltage control. The produced electrophotographic photosensitive member was subjected to paper passing durability (HH durability) at 28 ° C. and 90% RH using this apparatus. The sequence was an intermittent mode in which the print was stopped once for each print.

When the toner ran out, the toner was replenished and the image was durable until a problem occurred in the image. Further, abrasion was performed for 15 minutes using a Taber abrasion tester using a polishing tape, and the weight loss at that time was measured.

Further, 3000 L is applied to a part of the electrophotographic photosensitive member.
ux, the light of a white fluorescent lamp was applied for 10 minutes, and after standing for 10 minutes, the bright portion potential was measured, and how much the bright portion potential decreased before the application of the light was measured to obtain a photo memory value.

Further, regarding the solvent cracking property, sebum was adhered to the surface and allowed to stand for 48 hours, and the presence or absence of solvent cracking was observed under a microscope to observe the presence or absence of cracks.

Table 3 shows the results.

[Examples 2 to 12] Except for using Examples 2 to 12 in Table 3 as the binder resin for the charge transport layer,
An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1. Table 3 shows the results.

[0093]

[Table 8] The mixing ratio between terephthalic acid chloride and isophthalic acid chloride was 1: 1 in molar ratio.

[Comparative Examples 1 to 5] An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the binder resin of the charge transport layer used was one of the conditions 1 to 5 shown in Table 4. Table 5 shows the results.

[0095]

[Table 9]

[0096]

[Table 10]

Example 13 An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 1, except that the following polymer was used as the binder resin of the charge transport layer, and the ghost was also evaluated. Table 7 shows the results.

The polymer used in this example was 10 mmol of 2,2-bis [3 (8-nonenyl) -4-hydroxyphenyl] propane, 3 g of sodium hydroxide and 0.125 g of tributylbenzylammonium chloride in 5 ml of water.
In 0 ml, stir and dissolve, and separately add terephthalic acid chloride and isophthalic acid chloride to 25 ml of methylene chloride.
The methylene chloride layer was added to the aqueous layer under vigorous stirring, and the mixture was stirred for 3 hours. Acetic acid 20 mm after 3 hours
After the addition of methylene chloride, the methylene chloride layer was separated, washed with water until the methylene chloride layer became neutral, and then dropped into methanol, and the polymer was taken out and filtered. The molecular weight by gel permeation chromatography is shown in Table 6. Yield 75
%.

As a ghost evaluation method, a ghost evaluation pattern was diverted around the drum on the image and then switched to a halftone image, and it was visually determined whether a ghost was generated on the halftone image.

[0100]

[Table 11]

[Examples 14 to 24] The binders of Example Nos. An electrophotographic photoreceptor was prepared and evaluated in the same manner as in Example 13 except that those of Nos. 14 to 24 were used. Table 7 shows the results.

[0102]

[Table 12]

Comparative Examples 6 to 10 An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 13, except that the binder of the charge transport layer used was one of the conditions 1 to 5 shown in Table 4 above. Table 8 shows the results.

[0104]

[Table 13]

[0105]

The electrophotographic photoreceptor of the present invention has excellent solvent crack resistance without impairing the mechanical strength, has high mechanical strength, and has good electric resistance against discharge due to direct charging. It has become possible to provide an electrophotographic photosensitive member suitable for direct charging, which has less photo memory and is easy to manufacture, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a schematic configuration of an electrophotographic apparatus having a process cartridge having an electrophotographic photosensitive member of the present invention.

FIG. 2 is a diagram illustrating an example of a block diagram of a facsimile having the electrophotographic photosensitive member of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrophotographic photoreceptor of this invention 2 axis 3 Primary charging means 4 Image exposure light 5 Developing means 6 Transfer means 7 Transfer material 8 Image fixing means 9 Cleaning means 10 Pre-exposure light 11 Process cartridge 12 Rail 13 Image reading section 14 Controller 15 Receiving circuit 16 transmitting circuit 17 telephone 18 line 19 image memory 20 CPU 21 printer controller 22 printer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor ▲ Akira Yoshi ▼ 3-2-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (4)

[Claims] 1. An electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the surface layer of the electrophotographic photosensitive member contains a polymer having a structural unit represented by the following formula (1). An electrophotographic photosensitive member characterized by the following. Embedded image (Wherein, R _{1 to} R _{12 each} represent a hydrogen atom, a halogen atom, an alkyl group or an aryl group which may be substituted, and m and n each represent an integer of 1 to 10) 2. An electrophotographic photosensitive member having a photosensitive layer on a conductive support, wherein the surface layer of the electrophotographic photosensitive member contains a polymer having a structural unit represented by the following formula (2). An electrophotographic photosensitive member characterized by the following. Embedded image (In the formula, X represents a single bond, -O-, -S-, or an optionally substituted alkylidene group or a cycloalkylidene group, and at least one of R _{21 to} R ₂₈ is-(CH
₂ ) _p -CH = CH ₂ (p is an integer of 2 or more),
Those other than the above groups represent a hydrogen atom, a halogen atom, and an alkyl group or an aryl group which may be substituted. R
₂₉ to R ₃₂ represents a hydrogen atom, a halogen atom, each of which may be substituted alkyl group or an aryl group. ) 3. The electrophotographic photoreceptor according to claim 1 or 2, and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means are integrally supported and detachably attached to an electrophotographic apparatus main body. A process cartridge, characterized in that: 4. An electrophotographic apparatus comprising: the electrophotographic photoreceptor according to claim 1; a charging unit; an image exposing unit; a developing unit; and a transfer unit.