JP2001154392A - Electrophotographic photoreceptor, and method and device for formation of image and process cartridge using that photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop an electrophotographic photoreceptor which has high surface hardness, wear resistance, scratch resistance and interlayer adhesion property and stable electrophotographic characteristics for repeated use even under conditions of high temperature and high humidity, and therefore, with which good images can be obtained for repeated use, and to provide a method and device for the formation of an image and a process cartridge using the aforementioned photoreceptor. SOLUTION: In the electrophotographic photoreceptor having a photosensitive layer on a conductive supporting body, the surface layer of the electrophotographic photoreceptor contains a siloxane resin having a structural unit having a charge transfer performance and having a crosslinked structure. The content of silane monomers in the photosensitive layer is >=1 ppm and <=500 ppm.

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 (hereinafter, also simply referred to as a photosensitive member), an image forming method using the photosensitive member, an image forming apparatus, and a process cartridge.

[0002]

2. Description of the Related Art In recent years, an organic photoconductor containing an organic photoconductive substance has been most widely used as an electrophotographic photoconductor. Organic photoreceptors are advantageous over other photoreceptors in that materials that can be used for various exposure light sources from visible light to infrared light can be easily developed, materials that do not pollute the environment can be selected, and manufacturing costs are low. It is. However, the only drawback is that the mechanical strength is weak, and the photoreceptor surface is deteriorated or scratched when copying or printing many sheets.

The surface of an electrophotographic photosensitive member is electrically and electrically controlled by a charger, a developing device, a transfer means, a cleaning device, and the like.
Since a mechanical external force is directly applied, durability against them is required. Specifically, it is required to have mechanical durability against abrasion and scratches on the surface of the photoreceptor due to rubbing, film intrusion due to foreign matter mixing, impact during paper jam processing, and the like. Above all, with respect to durability against scratches and film peeling due to impact, a strength as high as that of an inorganic photoreceptor is strongly required. Further, durability against deterioration of the photoreceptor surface due to ozone or active oxygen generated during corona charging is required.

In order to satisfy the various characteristics required for the photoreceptor surface as described above, various items have been studied so far. That is, by using BPZ polycarbonate as a binder (binder resin) on the surface of the organic photoreceptor,
It has been reported that the surface wear characteristics and toner filming characteristics are improved. Japanese Patent Application Laid-Open No. Hei 6-118681 reports that a curable silicone resin containing colloidal silica is used as a surface protective layer of a photoreceptor.

However, the photoreceptor using the BPZ polycarbonate binder still lacks abrasion resistance and does not have sufficient durability. On the other hand, in the surface layer of the curable silicone resin containing colloidal silica, the abrasion resistance is improved, but the electrophotographic properties after repeated use are insufficient, and fogging and image blur are liable to occur. Not enough.

As a method for improving such a defect, Japanese Patent Application Laid-Open No. 9-124943 and Japanese Patent Application Laid-Open No. 9-190004
In Japanese Patent Application Laid-Open No. H11-264, a photoreceptor having a resin layer in which an organosilicon-modified hole transporting compound is bound in a curable organosilicon polymer as a surface layer is proposed.

[0007] However, the siloxane-based resin layer as described above contains a silane monomer which remains without reacting, and may remain in the film even after heat curing. If the residual amount is large, the film strength decreases due to a decrease in crosslink density, image blur due to the effect of the residual hydroxyl group, and the residual solvent becomes a charge trap. Sufficient electrostatic and mechanical durability cannot be obtained.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems by providing a high surface hardness, a high abrasion resistance, a high scratch resistance and a high interlayer adhesion, and an electrophotographic characteristic upon repeated use. An object of the present invention is to develop an electrophotographic photoreceptor which is stable even under high temperature and high humidity, and thus can obtain a good image even in repeated use. Also, an image forming method, an image forming apparatus and a process using the photoreceptor It is to provide a cartridge.

[0009]

The present inventors have made intensive efforts to solve the above-mentioned problems, and as a result, it has been found that the object of the present invention can be attained by adopting one of the following constitutions.

[1] In an electrophotographic photosensitive member having a photosensitive layer on a conductive support, a surface layer of the electrophotographic photosensitive member includes a siloxane-based resin having a structural unit having a charge transporting property and having a crosslinked structure. An electrophotographic photoreceptor, wherein the silane monomer content of the photosensitive layer is 500 ppm or less.

[2] The electrophotographic photoreceptor according to [1], wherein the siloxane-based resin having a crosslinked structure is a siloxane-based resin having a structure represented by the following general formula (1). In the general formula (1) -Si-Y- (X) _n , X represents a structural unit having charge transport performance, and Y represents a divalent or higher valent atom or group excluding adjacent bonding atoms (Si and C). . n represents an integer of 1 or more.

[3] The electrophotographic photosensitive member according to [1] or [2], wherein the surface layer contains colloidal silica.

[4] The silane monomer is methyltrimethoxysilane [1], [2]
Or, the electrophotographic photosensitive member according to [3].

[5] The silane monomer is dimethyldimethoxysilane [1], [2]
Or, the electrophotographic photosensitive member according to [3].

[6] The electrophotographic photosensitive member according to any one of [1] to [5], wherein the photosensitive layer contains an antioxidant.

[7] In the electrophotographic image forming method, the electrophotographic photoreceptor includes at least steps of charging, exposing, developing, and cleaning the electrophotographic photoreceptor. An image forming method, comprising using the electrophotographic photosensitive member according to any one of the above items.

[8] In an image forming apparatus having an electrophotographic photosensitive member and at least means for charging, image exposure, development, and cleaning, the electrophotographic photosensitive member according to any one of [1] to [6]. An image forming apparatus using the electrophotographic photosensitive member of (1).

[0018]

[9] A process cartridge used in an image forming apparatus having an electrophotographic photoreceptor and at least means for charging, image exposing, developing, and cleaning includes [1] to
[6] the electrophotographic photosensitive member and the charger according to any one of [1],
A process cartridge having an image exposing device, a developing device, and a cleaning device in an integrated manner, and being designed to be freely inserted into and removed from the image forming apparatus.

The present invention will be further described. In the present invention, the siloxane-based resin having a crosslinked structure is produced by a known method, that is, using an organosilicon compound having a hydroxyl group or a hydrolyzable group. This organosilicon compound is represented by the following general formulas (A) to (D),
When Z in the general formula is a hydrolyzable group, the hydrolyzable group includes a methoxy group, an ethoxy group, a methylethylketoxime group, a diethylamino group, an acetoxy group, a propenoxy group, a propoxy group, a butoxy group, a methoxyethoxy group, and the like. No.

Examples of the organic group in which carbon is directly bonded to silicon represented by R _{1 to} R ₆ include alkyl groups such as methyl, ethyl, propyl and butyl, aryl groups such as phenyl, tolyl, naphthyl and biphenyl, and γ. An epoxy-containing group such as glycidoxypropyl and β- (3,4-epoxycyclohexyl) ethyl; a (meth) acryloyl group including γ-acryloxypropyl and γ-methacryloxypropyl;
hydrous groups such as γ-hydroxypropyl and 2,3-dihydroxypropyloxypropyl, vinyl groups such as vinyl and propenyl, mercapto groups such as γ-mercaptopropyl, γ-aminopropyl, N-β (aminoethyl)-
Examples include amino-containing groups such as γ-aminopropyl, halogen-containing groups such as γ-chloropropyl, 1,1,1-trifluoropropyl, nonafluorohexyl, and perfluorooctylethyl, and other nitro and cyano-substituted alkyl groups. be able to. Further, R _{1 to} R ₆ may have the same or different organic groups.

The above-mentioned organosilicon compound used as a raw material of the siloxane-based resin having a charge transporting property in the present invention is generally prepared when the number n of hydrolyzable groups bonded to a silicon atom is one. The polymerization reaction is suppressed. When n is 2, 3 or 4, a polymerization reaction is likely to occur, and especially when 3 or 4, the crosslinking reaction can be advanced to a high degree. Therefore, by controlling these, it is possible to control the preservability of the obtained coating layer liquid, the hardness of the coating layer, and the like.

[0022]

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In the formula, R _{1 to} R ₆ represent an organic group in which carbon is directly bonded to silicon in the formula, and Z represents a hydroxyl group or a hydrolyzable group.

Further, as a raw material of the resin having the crosslinked structure, a hydrolyzed condensate obtained by hydrolyzing the above organosilicon compound under acidic or basic conditions to oligomerize or polymerize can be used.

The resin having a cross-linked structure in the present invention means that a part of the resin component is cross-linked (cross-linked) in the coating solution or in the coating and drying step of the raw material of the cross-linkable resin containing a siloxane bond. This means a resin that forms a resin layer having high hardness.

The silane monomer content remaining in the photosensitive layer after the crosslinking is 500 ppm or less, particularly preferably 1 ppm or more and 400 ppm or less. These measured values of the content can be obtained using a known quantitative analysis method,
Quantitative analysis by gas chromatography is preferred.

[0027] The amount of the silane monomer must be 500 ppm or less. If it is more than 500 ppm, the film strength is reduced due to a decrease in crosslink density, image blur due to the influence of the residual hydroxyl group, the residual solvent becomes a charge trap, and the stability of the repetitive potential characteristic is reduced due to charge accumulation there. Electrostatic and mechanical durability cannot be obtained. Also, 1pp
If it is less than m, it is difficult to make it technical, and the performance is slightly deteriorated.

The above-mentioned surface layer may contain colloidal silica having a hydroxyl group or a hydrolyzable group to form a surface layer in which silica particles are incorporated in a part of the crosslinked structure.

In the present invention, the term "charge transport performance" is defined as a value by which a detection current due to charge transport can be obtained by a known method capable of detecting the charge transport capability of the ordinary Time-Of-Flight method. You can also.

In the present invention, the structural unit having a charge transporting ability is a structural unit that exhibits the property of having electron or hole drift mobility (= charge transporting performance imparting group). The siloxane-based resin having a crosslinked structure in the present invention contains a compound generally used as a charge-transporting substance (hereinafter also referred to as a charge-transporting compound or CTM) as a partial structure in the curable siloxane-based resin,
The resin is provided with a charge transporting ability.

For example, the hole transport type CTM includes xazole, oxadiazole, thiazole, triazole,
Imidazole, imidazolone, imidazoline, bisimidazolidin, styryl, hydrazone, benzidine, pyrazoline, stilbene compound, amine, oxazolone, benzothiazole, benzimidazole, quinazoline, benzofuran, acridine, phenazine, aminostilbene, poly-N-vinylcarbazole, poly It has a chemical structure such as -1-vinylpyrene and poly-9-vinylanthracene, or contains it as a partial structure.

On the other hand, the electron transport type CTM includes succinic anhydride, maleic anhydride, phthalic anhydride, pyromellitic anhydride, melitic anhydride, tetracyanoethylene, tetracyanoquinodimethane, nitrobenzene, dinitrobenzene, trinitrobenzene. , Tetranitrobenzene, nitrobenzonitrile, picryl chloride, quinone chlorimide, chloranil, bromanyl, benzoquinone, naphthoquinone, diphenoquinone, tropoquinone, anthraquinone, 1-chloroanthraquinone, dinitroanthraquinone, 4-nitrobenzophenone, 4,4'-dinitrobenzophenone , 4-nitrobenzalmalonedinitrile, α-cyano-β- (p-cyanophenyl) -2-
(P-chlorophenyl) ethylene, 2,7-dinitrofluorenone, 2,4,7-trinitrofluorenone,
2,4,5,7-tetranitrofluorenone, 9-fluorenylidenedicyanomethylenemalononitrile, polynitro-9-fluoronylidenedicyanomethylenemalonodinitrile, picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, It has a chemical structure such as 3,5-dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, phthalic acid, and melitic acid, or contains as a partial structure.

In the present invention, the preferable charge-transporting performance-imparting group (X in the following general formula (1)) includes the commonly used charge-transporting compound as described above, and includes carbon atoms constituting the charge-transporting compound. Through or via a carbon atom of the compound containing the charge transporting compound as a partial structure,
It is contained in a siloxane-based resin having a crosslinked structure via a connecting atom of Y in the following formula. In the general formula (1) -Si-Y- (X) _n , Y is a divalent or higher valent atom excluding adjacent bonding atoms (Si and C). However, when Y is a trivalent or higher atom, the bond of Y other than Si and C in the above formula is bonded to any of the constituent atoms in the siloxane-based resin having the crosslinkable structure capable of bonding. Or, it has a structure linked to another atom or molecular group. Of course, Si is not divalent but generally tetravalent, and thus has a bond other than the above and is connected to another atom.

As the Y atom, particularly, an oxygen atom (O),
A sulfur atom (S) and a nitrogen atom (N) are preferred.

The structural unit having charge transporting performance (= charge transporting performance imparting group) X is shown as a monovalent group in the above formula, but two charge transporting compounds to be reacted with the curable siloxane resin. When it has the above reactive functional groups, it may be bonded as a divalent or higher valent crosslink group in the curable resin, or may be bonded simply as a pendant group.

The above-mentioned atoms, that is, atoms having two or more valences excluding the adjacent bonding atoms (Si and C) are hydroxyl groups, mercapto groups, amine groups and hydroxyl groups introduced into the compound having the charge transporting property, respectively. It is a linking group formed by a reaction with an organic silicon compound having a group and incorporating a charge transport compound as a partial structure into a curable siloxane-based resin.

Next, the charge transporting compound having a hydroxyl group, a mercapto group and an amine group used in the present invention will be described.

The charge transporting compound having a hydroxyl group is a charge transporting substance having a commonly used structure and a compound having a hydroxyl group. That is, typically, a charge transporting compound represented by the following general formula that can form a resin layer by bonding to a curable organosilicon compound can be exemplified, but is not limited to the following structure. Any compound may be used as long as it has charge transport performance and has a hydroxyl group. X- (R ₁ -OH) mm ≧ 1 wherein X: charge transporting performance-imparting group, R ₁ : single bond, each substituted or unsubstituted alkylene, arylene group, m: preferably 1 to 5 .

Among them, the following are typical ones. Further, for example, a triarylamine compound is a compound having a triarylamine structure such as triphenylamine and having a hydroxyl group bonded to a carbon atom via a carbon atom constituting the group. 1. Triarylamine compounds

[0040]

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2. Hydrazine compounds

[0042]

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3. Stilbene compounds

[0044]

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4. Benzidine compound

[0046]

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5. Butadiene compound

[0048]

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6. Other compounds

[0050]

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Next, a synthesis example of a charge transporting compound having a hydroxyl group will be described. Synthesis of Exemplified Compound T-1

[0052]

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Step A In a four-headed kolben equipped with a thermometer, a cooling tube, a stirrer, and a dropping funnel, 49 g of the compound (1) and phosphorus 184 chloride were added.
g was added and dissolved by heating. 117 g of dimethylformamide was gradually added dropwise from the dropping funnel.
The mixture was kept at ９５95 ° C. and stirred for about 15 hours. Next, the reaction solution was gradually poured into a large excess of warm water, and then slowly cooled while stirring.

After the precipitated crystals were filtered and dried, they were purified by adsorption of impurities using silica gel or the like and recrystallization with acetonitrile to obtain Compound (2). Yield 30
g. Step B 30 g of compound (2) and 100 ml of ethanol were charged into a kolben and stirred. After gradually adding 1.9 g of sodium borohydride, the solution was kept at 40 to 60 ° C. and stirred for about 2 hours. Next, the reaction solution was gradually poured into about 300 ml of water, and stirred to precipitate crystals. After filtration, the resultant was sufficiently washed with water and dried to obtain a compound (3). The yield was 30 g.

Synthesis of Exemplified Compound S-1

[0056]

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Step A In a 300 ml Kolben equipped with a thermometer and a stirrer, add C
Then, 30 g of u, 60 g of K ₂ CO ₃ , 8 g of compound (1) and 100 g of compound (2) were added, and the mixture was heated to about 180 ° C. and stirred for 20 hours. After cooling, the mixture was filtered and purified by column to obtain 7 g of compound (3). Step B A 100 ml kolben equipped with a thermometer, a dropping funnel, an argon gas introducing device and a stirrer was set to an argon gas atmosphere, and 7 g of the compound (3), 50 ml of toluene, and 3 g of phosphoryl chloride were added thereto. While stirring at room temperature, D
2 g of MF was slowly added dropwise, and then the temperature was raised to about 80 ° C. and the mixture was stirred for 16 hours. The mixture was poured into warm water of about 70 ° C. and cooled. This was extracted with toluene, and the extract was washed with water until the pH of the water reached 7. After drying over sodium sulfate, the mixture was concentrated and purified by column to obtain 5 g of compound (4). Step C 100 ml with an argon gas introduction device and a stirring device
1.0 g of t-BuOK and 60 ml of DMF were charged into the Kolben, and the atmosphere was changed to an argon gas atmosphere. Compound (4)
2.0 g and 2.2 g of the compound (5) were added, and the mixture was stirred at room temperature for 1 hour. This was poured into a large excess of water, extracted with toluene, the extract was washed with water, dried over sodium sulfate,
After concentration, column purification was performed, and 2.44 g of compound (6) was obtained.
I got Step D Toluene was charged into a 100 ml kolben equipped with a thermometer, a dropping funnel, an argon gas introducing device and a stirring device, and the atmosphere was changed to an argon gas atmosphere. 15 ml of a hexane solution of n-BuLi (1.72 M) was added thereto, and the mixture was heated to 50 ° C. To this, 2.44 g of compound (6) was added in 30 ml of toluene.
The dissolved liquid was added dropwise, and the mixture was stirred at 50 ° C. for 3 hours. After cooling to −40 ° C., 8 ml of ethylene oxide was added, the temperature was raised to −15 ° C., and the mixture was stirred for 1 hour.
Thereafter, the temperature was raised to room temperature, 5 ml of water was added, and ether 2 was added.
After extraction with 00 ml, the extract was washed with saturated saline.
After washing the washing solution to pH, it was dried over sodium sulfate, concentrated and purified by column to obtain 1.0 g of compound (7).

Next, specific examples of the charge transporting compound having a mercapto group are shown below. The charge transporting compound having a mercapto group is a charge transporting substance having a commonly used structure and a compound having a mercapto group.
That is, typically combined with a curable organosilicon compound,
Examples of the charge transporting compound represented by the following general formula that can form a resin layer include, but are not limited to, the following structure, having charge transporting performance, and having a mercapto group. Any compound may be used. X- (R ₁ -SH) mm ≧ 1 wherein X: a charge transporting performance-imparting group, R ₁ : a single bond, each substituted or unsubstituted alkylene or arylene group, m: preferably 1 to 5 .

Among them, the following are typical ones.

[0060]

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Further, specific examples of the charge transporting compound having an amino group are shown below. The charge transporting compound having an amino group is a charge transporting substance having a commonly used structure,
And a compound having an amino group. That is, typically, a charge transporting compound represented by the following general formula that can form a resin layer by bonding to a curable organosilicon compound can be exemplified, but is not limited to the following structure. Any compound having charge transporting performance and having an amino group may be used.

X- (R ₁ -NR ₂ H) m m ≧ 1 where X: charge transporting performance-imparting group, R ₁ : single bond, each substituted or unsubstituted alkylene, arylene group, R ₂ : H , Each substituted or unsubstituted alkyl group and aryl group, m: preferably 1 to 5.

Among them, the following are typical ones.

[0064]

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In the case of a charge transporting compound having an amino group, in the case of a primary amine compound (—NH ₂ ), two hydrogen atoms may react with an organosilicon compound and be linked to a siloxane structure.

In the case of the secondary amine compound (—NHR), 1
Hydrogen atoms react with the organosilicon compound, and the remaining R may be a group remaining as a branch, a group causing a crosslinking reaction, or a compound group containing a charge transport substance.

The raw material composition ratio of the curable siloxane-based resin is as follows: organosilicon compound: (A) + (B) component 1
It is preferable to use 0.05 to 1 mol of the component (C) + (D) based on the mol.

When the colloidal silica (E) is added, 1 to 30 parts by mass of (E) is added to 100 parts by mass of the components (A) + (B) + (C) + (D). Preferably, it is used. When the reactive charge transporting compound (F) capable of forming a resin layer by reacting with the above-mentioned organosilicon compound or colloidal silica is added, (A) +
It is preferable to use 1 to 500 parts by mass of (F) based on 100 parts by mass of the components (B) + (C) + (D).

If the amount of the components (A) and (B) is small, the crosslinking density of the siloxane-based resin layer may be too low and the hardness may be insufficient. On the other hand, if the amount of the component (A) + (B) is too large, the crosslink density is too high and the hardness is sufficient, but a brittle resin layer may be formed. Excess or deficiency of the colloidal silica component of the component (E) has the same tendency as that of the component (A) + (B). On the other hand, when the amount of the component (F) is small, the charge transporting ability of the siloxane-based resin layer is small, causing a decrease in sensitivity and an increase in residual charge.
When the amount of the component (F) is large, the film strength of the siloxane-based resin layer tends to be weak.

The curable siloxane-based resin in the present invention means that a catalyst or a crosslinking agent is added to a monomer, oligomer or polymer having a siloxane bond in the structural unit in advance to form a new chemical bond to form a three-dimensional network structure. In addition, a siloxane bond can be promoted by a hydrolysis reaction and subsequent dehydration condensation to form a three-dimensional network structure from monomers, oligomers and polymers. Generally, a three-dimensional network structure can be formed by a condensation reaction of a composition comprising an alkoxysilane or a composition comprising an alkoxysilane and colloidal silica.

Examples of the catalyst for forming the above three-dimensional network structure include alkali metal salts of organic carboxylic acids, nitrous acid, sulfurous acid, aluminate, carbonic acid and thiocyanic acid, and organic amine salts (tetramethylammonium hydroxide, tetramethylammonium hydroxide). Methylammonium acetate), tin organic acid salts (stannas octoate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin mercaptide, dibutyltin thiocarboxylate, dibutyltin malate, etc.), aluminum, zinc octenoic acid, naphthenate And acetylacetone complex compounds.

An antioxidant having a hindered phenol, hindered amine, thioether or phosphite partial structure can be added to the resin layer in the present invention, which is effective for improving potential stability and image quality under environmental changes. is there.

Examples of the antioxidant having a hindered phenol partial structure include, for example, JP-A-1-118137 (P7
To P14), but not limited thereto.

Examples of the antioxidant having a hindered amine partial structure include, for example, JP-A-1-118138 (P7-P
The compounds described in 9) are mentioned, but not limited thereto.

The following compounds are used as antioxidants:
For example, “Irganox 1076”, “Irganox 1010”, “Irganox 1098”, “Irganox 245”, “Irganox 1330”, “Irganox 3114”, “Irganox 1076”
"3,5-di-t-butyl-4-hydroxybiphenyl" or more hindered phenols, "Sanol LS26
26, "Sanol LS765", "Sanol LS77
0 "," Sanol LS744 "," Tinuvin 144 ",
“Tinuvin 622LD”, “Mark LA57”, “Mark LA67”, “Mark LA62”, “Mark LA6”
8 "," mark LA63 "or more hindered amine-based,
"SUMILIZER TPS", "SUMILIZER TP-D" or higher thioether type, "Mark 2112", "Mark PE"
P8 "," Mark PEP24G "," Mark PEP.3 "
6 "," Mark 329K "," Mark HP10 "or more phosphite-based. In particular, hindered phenol and hindered amine antioxidants are preferred.

The following are specific examples of the compounds.

[0077]

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[0078]

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[0079]

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[0080]

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[0081]

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[0082]

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It is preferable to use 0.1 to 10 parts by mass of the antioxidant based on 100 parts by mass of the resin layer composition.

The layer constitution of the electrophotographic photoreceptor of the present invention is not particularly limited, but may be a charge generation layer, a charge transport layer, or a charge generation / charge transport layer (a single layer having both functions of charge generation and charge transport). It is preferable to adopt a structure in which a photosensitive layer such as a photosensitive layer) and a resin layer of the present invention are provided thereon. Further, each of the charge generation layer, the charge transport layer, or the charge generation / charge transport layer may be composed of a plurality of layers.

The charge generating substance (CGM) contained in the photosensitive layer of the present invention includes, for example, phthalocyanine pigment, polycyclic quinone pigment, azo pigment, perylene pigment, indigo pigment,
Quinacridone pigments, azurenium pigments, squarylium dyes, cyanine dyes, pyrylium dyes, thiopyrylium dyes, xanthene dyes, triphenylmethane dyes, styryl dyes, and the like.
In M), a layer is formed alone or together with a suitable binder resin.

The charge transport material (C) contained in the photosensitive layer
TM) include, for example, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, imidazoline derivatives, bisimidazolidine derivatives, styryl compounds, hydrazone compounds, benzidine compounds, pyrazoline derivatives, stilbenes Compound,
Amine derivatives, oxazolone derivatives, benzothiazole derivatives, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives, phenazine derivatives, aminostilbene derivatives, poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene, etc. These charge transport materials (CTM) are usually used to form a layer together with a binder.

The binder resin contained in the photosensitive layer having a single-layer structure and the charge generation layer (CGL) and the charge transport layer (CTL) in the case of a multilayer structure include polycarbonate resin,
Polyester resin, polystyrene resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl butyral resin, polyvinyl acetate resin, styrene-butadiene resin, vinylidene chloride-acrylonitrile copolymer resin, vinyl chloride-maleic anhydride Copolymer resins, urethane resins, silicone resins, epoxy resins, silicon-alkyd resins, phenol resins, polysilane resins, polyvinyl carbazole, and the like can be used.

In the present invention, the ratio between the charge generating substance and the binder resin in the charge generating layer is from 1: 5 to 5: 1 by mass.
Is preferred. The thickness of the charge generation layer is preferably 5 μm or less, particularly preferably 0.05 to 2 μm.

The charge transport layer is formed by dissolving the charge transport material and the binder resin in a suitable solvent, and applying and drying the solution. The mixing ratio of the charge transport material and the binder resin is preferably from 3: 1 to 1: 3 by mass ratio.

The thickness of the charge transporting layer is preferably 5 to 50 μm, particularly preferably 10 to 40 μm. When a plurality of charge transport layers are provided, the thickness of the upper layer of the charge transport layer is 10 μm.
m or less, and preferably smaller than the total thickness of the charge transport layer provided below the charge transport layer.

The siloxane-based resin layer of the present invention may also serve as the above-mentioned charge transport layer, but is preferably provided on a photosensitive layer such as a charge transport layer or a charge generation layer or a single-layer type charge generation / transport layer. It is preferable to provide these layers as separate layers. In this case, it is more preferable to provide an adhesive layer between the photosensitive layer and the resin layer of the present invention.

Next, the conductive support of the electrophotographic photoreceptor of the present invention includes: 1) a metal plate such as an aluminum plate or a stainless steel plate; 2) a support such as paper or a plastic film;
A thin metal layer such as aluminum, palladium, or gold provided by lamination or vapor deposition. 3) On a support such as paper or plastic film,
Examples thereof include those in which a layer of a conductive compound such as a conductive polymer, indium oxide, or tin oxide is provided by coating or vapor deposition.

The material of the conductive support used in the present invention is mainly aluminum, copper, brass, steel,
A belt-shaped or drum-shaped metal material such as stainless steel or another plastic material is used. Among them, aluminum excellent in cost, workability and the like is preferably used, and a thin-walled cylindrical aluminum tube usually formed by extrusion or drawing is often used.

The shape of the support may be a drum shape, a sheet shape, or a belt shape, and is preferably a shape optimal for the applied electrophotographic apparatus.

Solvents or dispersion media used in the production of the photoreceptor of the present invention include n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N, N-dimethylformamide, acetone, methylethylketone,
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, dioxolan, dioxane,
Methanol, ethanol, butanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide,
Methyl cellosolve and the like. Although the present invention is not limited to these, dichloromethane, 1,2-dichloroethane, methyl ethyl ketone and the like are preferably used. In addition, these solvents can be used alone or as a mixed solvent of two or more kinds.

The coating method for producing the electrophotographic photosensitive member of the present invention includes dip coating, spray coating,
Coating methods such as circular amount control type coating are used, but the coating process on the surface layer side of the photosensitive layer is spray coating or circular amount control type in order to minimize dissolution of the lower layer film and to achieve uniform coating processing. (A typical example is the circular slide hopper type.)
It is preferable to use a coating method such as coating. The spray coating is described in detail in, for example, JP-A-3-90250 and JP-A-3-269238,
The circular amount control type coating is described in, for example, JP-A-58-1.
It is described in detail in JP-A-89061.

The photoreceptor of the present invention is preferably heated and dried at a temperature of 50 ° C. or higher, preferably 60 to 200 ° C., after the surface layer is formed by coating. By this heating and drying, the remaining coating solvent can be reduced, and the curable resin layer can be sufficiently cured.

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

Materials for the intermediate layer include casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, polyvinyl butyral, and phenolic resin polyamides (nylon 6, nylon 66, nylon 610, copolymerized nylon, alkoxymethyl And an intermediate layer using polyurethane, gelatin, and aluminum oxide, or a hardening intermediate layer using a metal alkoxide, an organic metal chelate, or a silane coupling agent as described in JP-A-9-68870. The thickness of the intermediate layer is preferably from 0.1 to 10 μm, particularly preferably from 0.1 to 10 μm.
5 μm is preferred.

In the present invention, a coating for compensating for surface defects of the support is provided between the support and the intermediate layer. A conductive layer for the purpose of preventing generation and the like can be provided. This conductive layer is made of carbon black,
It can be formed by applying and drying a solution in which conductive powder such as metal particles or metal oxide particles is dispersed in a suitable binder resin. The thickness of the conductive layer is preferably 5 to 40 μm, particularly preferably 10 to 30 μm.

The electrophotographic photoreceptor of the present invention can be applied to general electrophotographic devices such as copiers, laser printers, LED printers, and liquid crystal shutter printers. It can be widely applied to devices such as light printing, plate making, and facsimile.

FIG. 1 is a sectional view showing an example of an image forming apparatus having the electrophotographic photosensitive member of the present invention.

In FIG. 1, reference numeral 10 denotes a photoreceptor drum (photoreceptor) serving as an image carrier, and an organic photosensitive layer is applied on the drum.
A photoreceptor coated with the resin layer of the present invention thereon is grounded and driven to rotate clockwise. Reference numeral 12 denotes a scorotron charger for uniformly charging the peripheral surface of the photosensitive drum 10 by corona discharge. Prior to the charging by the charger 12, in order to eliminate the history of the photoconductor in the previous image formation, exposure by the exposure unit 11 using a light emitting diode or the like may be performed to remove electricity from the peripheral surface of the photoconductor.

After the photosensitive member is uniformly charged, the image exposing device 13 performs image exposure based on the image signal. The image exposure device 13 in this figure uses a laser diode (not shown) as an exposure light source. The light on the photosensitive drum is scanned by the light whose optical path is bent by the reflection mirror 132 through the rotating polygon mirror 131, the fθ lens, and the like, and an electrostatic latent image is formed.

Next, the electrostatic latent image is developed by the developing device 14. Developing devices 14 each having a built-in developer composed of toner and carrier such as yellow (Y), magenta (M), cyan (C), black (K), etc., at the periphery of the photosensitive drum 10.
First, development of the first color is performed by a developing sleeve 141 which rotates with a built-in magnet and holding a developer. The developer comprises, for example, a carrier in which an insulating resin is coated around a ferrite core, and a toner in which a pigment corresponding to a color and a charge control agent, silica, titanium oxide, etc. are added using polyester as a main material. The developer is regulated to a layer thickness of 100 to 600 μm on the developing sleeve 141 by a layer forming means (not shown), and is conveyed to a developing area to be developed. At this time, normally, a DC and / or AC bias voltage is applied between the photosensitive drum 10 and the developing sleeve 141 to perform the development.

In the color image formation, after the visualization of the first color is completed, the image forming process for the second color is started, and the uniform charging is again performed by the scorotron charger 12 to form the latent image of the second color. It is formed by the exposure device 13. An image forming process similar to that for the second color is performed for the third color and the fourth color, and a visible image of four colors is formed on the peripheral surface of the photosensitive drum 10.

On the other hand, in a monochrome electrophotographic apparatus, the developing device 1
Reference numeral 4 is composed of one kind of black toner and can form an image by one development.

After the image is formed, the recording paper P is fed to the transfer area by the rotation of the paper feed roller 17 at the time when the transfer timing is adjusted.

In the transfer area, a transfer roller (transfer device) 1 is mounted on the peripheral surface of the photosensitive drum 10 in synchronization with the transfer timing.
8, the multicolor image is transferred collectively by sandwiching the fed recording paper P.

Next, the recording paper P is neutralized by a separation brush (separator) 19 brought into pressure contact with the transfer roller almost at the same time, and separated by the peripheral surface of the photosensitive drum 10 to be conveyed to the fixing device 20 where the heat roller 201 and pressure roller 2
After the toner is welded by heating and pressurizing 02, the toner is discharged to the outside of the apparatus via the discharge roller 21. The transfer roller 18 and the separation brush 19 are retracted and separated from the peripheral surface of the photosensitive drum 10 after the recording paper P has passed to prepare for the formation of the next toner image.

On the other hand, the photosensitive drum 10 from which the recording paper P has been separated removes and cleans the residual toner by pressing the blade 221 of the cleaning device 22 and receives the charge removal by the exposure unit 11 and the charge by the charger 12 again. The next image forming process is started. When a color image is formed on the photoconductor by superimposition, the blade 221 moves immediately after the cleaning of the photoconductor surface and retreats from the peripheral surface of the photoconductor drum 10.

Reference numeral 30 denotes a detachable process cartridge in which a photosensitive member, a charging device, a transfer device / separator, and a cleaning device are integrated.

The electrophotographic image forming apparatus is constructed by integrally combining the above-described photoreceptor, a developing device, a cleaning device, and other components as a process cartridge, and designing this unit freely into and out of the apparatus main body. You may. Also, a charger, an image exposure device, a developing device, a transfer or separation device,
A process cartridge is formed by integrally supporting at least one of the cleaning units together with the photoreceptor to form a single unit detachably mountable to the apparatus main body, and is designed to be freely inserted and removed using guide means such as rails of the apparatus main body. It is good.

When the image forming apparatus is used as a copying machine or a printer, the image exposure is performed by irradiating reflected light or transmitted light from the original to the photoreceptor, or by reading the original with a sensor and converting it into a signal. Scanning of a laser beam, driving of an LED array, or driving of a liquid crystal shutter array is performed by irradiating the photosensitive member with light.

When used as a facsimile printer, the image exposure unit 13 performs exposure for printing received data.

[0116]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto.

Example 1 A photoreceptor was manufactured as described below. <Conductive Substrate> Cylindrical aluminum substrate having a diameter of 80 mm and a length of 360 mm <Intermediate layer> A polyamide resin (CM8000, manufactured by Toray Industries, Inc.) 60 g methanol 2000 ml was mixed and dissolved to prepare an intermediate layer coating solution. This coating solution was applied on a cylindrical aluminum substrate by a dip coating method, and dried at room temperature to form an intermediate layer having a thickness of 0.3 μm. <Charge Generating Layer> Charge generating substance: titanyl phthalocyanine (the maximum peak of Bragg angle 2θ in Cu-Kα X-ray diffraction is 27.3 °) 60 g Silicone resin solution (KR5240, 15% xylene-butanol solution, Shin-Etsu Chemical Co., Ltd.) 700 g 2000 ml of methyl ethyl ketone was mixed and dispersed for 10 hours using a sand mill to prepare a charge generating layer coating solution. This coating solution was applied on the intermediate layer by a dip coating method to form a 0.2 μm-thick charge generation layer. <Charge Transport Layer> 200 g of a charge transport material (D1) 300 g of bisphenol Z-type polycarbonate (Iupilon Z300, manufactured by Mitsubishi Gas Chemical Co., Ltd.) 2000 g of 1,2-dichloroethane was mixed and dissolved to prepare a charge transport layer coating solution. This coating solution is applied on the charge generation layer by a dip coating method,
A charge transport layer having a thickness of 25 μm was formed.

[0118]

Embedded image

[0119] A commercially available primer PC-7J (manufactured by Shin-Etsu Chemical Co., Ltd.) was diluted twice with toluene, and 100 μl after coating.
C. for 30 minutes to form an adhesive layer having a dry film thickness of 0.3 .mu.m.

Molecular sieve 4A was added to 10 parts by mass of a polysiloxane resin (containing 1% by mass of silanol groups) composed of 80% by mol of methylsiloxane units and 20% by mol of methyl-phenylsiloxane units.
It was left to stand for 5 hours for dehydration treatment. This resin was dissolved in a mixed solvent of 5 parts by weight of 1-butanol and 5 parts by weight of methanol, and 5 parts by weight of methyltrimethoxysilane and 0.2 parts by weight of dibutyltin acetate were added to form a uniform solution.

6 parts by mass of dihydroxymethyltriphenylamine (Exemplified Compound T-1) was added and mixed, and this solution was applied as a protective layer having a dry film thickness of 1 μm.
After drying at 0 ° C. for 1 hour, the photoreceptor of Example 1 was produced.

The content of the silane monomer component in the obtained photosensitive layer was measured under the following conditions.
Met. Apparatus: HP5890 Column: DB-WAX 30 mm × 0.32 mm ID,
0.25 μm film Detector: FID Detector temperature: 150 ° C. Injection temperature: 150 ° C. Column flow rate: 1.7 ml / min Linear velocity 35.3 cm
/ Sec Spirit ratio: 16/1 Sample injection volume: 0.1-0.2 μl.

Example 2 The polysiloxane resin of the protective layer in Example 1 was a polysiloxane composed of 30 mol% of methylsiloxane units, 40 mol% of ethylsiloxane units, 20 mol% of dimethylsiloxane units and 10 mol% of diethylsiloxane units. A photoreceptor of Example 2 was made in exactly the same manner except that the resin (containing 2% by mass of a silanol group) was used.

The silane monomer content of this photosensitive layer is 2
It was 30 ppm. Example 3 A photoconductor of Example 3 was produced in the same manner as in Example 2, except that the drying conditions were changed to 100 ° C. for 1 hour.

The photosensitive layer had a silane monomer content of 40.
It was 0 ppm. Example 4 Except that dihydroxymethyltriphenylamine (exemplary compound T-1) in the protective layer in Example 1 was replaced with hydrazone-type exemplified compound H-1, and the drying conditions were changed to 110 ° C. for 1 hour. A photoconductor of Example 4 was produced in the same manner.

The photosensitive layer had a silane monomer content of 34.
It was 0 ppm. Example 5 The same procedure as in Example 4 was carried out except that dimethoxydimethylsilane was used instead of the polysiloxane resin, and the solvent for the protective layer was changed to a mixed solvent of 5 parts by mass of t-butyl alcohol and 5 parts by mass of ethanol. The photoconductor of Example 5 was produced.

The photosensitive layer had a silane monomer content of 23.
It was 0 ppm. Example 6 A charge transport layer was formed in the same manner as in Example 1 except that the following intermediate layer was provided between the conductive substrate and the charge generation layer. <Intermediate layer> Zirconium chelate compound ZC-540 (manufactured by Matsumoto Pharmaceutical Co., Ltd.) 200 g Silane coupling agent KBM-903 (manufactured by Shin-Etsu Chemical Co., Ltd.) 100 g Methanol 700 ml Ethanol 300 ml Dip and apply the above materials, and dry at 150 ° C. for 30 minutes. An intermediate layer having a thickness of 1.0 μm was formed.

On the other hand, dihydroxymethyltriphenylamine in the protective layer in Example 5 was replaced with 4- [2- (triethoxysilyl) ethyl] triphenylamine, and dibutyltin acetate was replaced with an aluminum chelate (aluminum chelate A).
(W), manufactured by Kawaken Fine Chemical Co., Ltd.), and a protective layer was formed in exactly the same manner as in Example 6, thereby producing a photoreceptor of Example 6.

The photosensitive layer had a silane monomer content of 20.
It was 0 ppm. Example 7 In Example 6, 5 parts by mass of colloidal silica was added to the protective layer, the film thickness was changed to 2 μm, and the drying condition was 130 ° C.
A photoconductor of Example 7 was prepared in the same manner except that the time was changed to 1 hour.

The photosensitive layer had a silane monomer content of 80.
ppm. Example 8 A photoconductor of Example 8 was prepared in the same manner as in Example 7, except that 0.6 parts by mass of a hindered phenolamine compound (Exemplary Compound 2-1) was added.

The silane monomer content of this photosensitive layer was 70%.
ppm. Example 9 In the same manner as in Example 1, an adhesive layer was manufactured.

Further, a commercially available curable siloxane resin K
60 parts by mass of P-854 (manufactured by Shin-Etsu Chemical Co., Ltd.) and 60 parts by mass of isopropanol were added and uniformly dissolved.
6 parts by mass of dihydroxymethyltriphenylamine (Exemplified Compound T-1) were added and mixed in the same manner as described above, and this solution was applied so as to form a protective layer having a dry film thickness of 1 μm.
After drying for one hour, the photoreceptor of Example 9 was produced.

The silane monomer content of this photosensitive layer is 5 p
pm. Example 10 Instead of the siloxane resin KP-854 of Example 9, X-
A photoreceptor of Example 10 was made in exactly the same manner except that 40-2239 (manufactured by Shin-Etsu Chemical Co., Ltd.) was used.

The photosensitive layer had a silane monomer content of 70%.
ppm. Example 11 Instead of the siloxane resin KP-854 of Example 9, X-
A photoreceptor of Example 11 was made in exactly the same manner except that 40-2269 (manufactured by Shin-Etsu Chemical Co., Ltd.) was used.

The photosensitive layer had a silane monomer content of 30.
ppm. Example 12 A photoconductor of Example 12 was produced in the same manner as in Example 1 except that the thickness of the protective layer was changed to 2 μm and the drying conditions were changed to 140 ° C. for 1 hour.

The silane monomer content of this photosensitive layer was 0.1.
It was 8 ppm. Comparative Example 1 Comparative Example 1 was performed in exactly the same manner as in Example 1 except that dihydroxymethyltriphenylamine in the protective layer was omitted.
Was produced.

The silane monomer content of this photosensitive layer was 24
It was 0 ppm. Comparative Example 2 A photoconductor of Comparative Example 2 was produced in exactly the same manner as in Example 3, except that 10 parts by mass of methyltrimethoxysilane was used.

The photosensitive layer had a silane monomer content of 55%.
It was 0 ppm. Evaluation of the above photoreceptor was carried out by mounting the present photoreceptor on a Konica 7050 (laser digital copying machine manufactured by Konica Corp .: equipped with a cartridge in which a photoreceptor and a charger, a developing device, a cleaning device, and a static eliminator were integrated). Then, the exposed portion potential (VL) and the unexposed portion potential (VH) of the photoreceptor before and after copying 100,000 sheets were measured under an environment of 20 ° C. and 60% RH.

The image evaluation during and after copying 100,000 sheets was performed by visual observation. The thickness loss is 10
The film thickness before and after copying million sheets was measured using an eddy current type film thickness meter (Fisherscope EDDY560C, manufactured by Fisher), and the difference was determined.

The above results are summarized in Table 1 below.

[0141]

[Table 1]

The photoconductors of Comparative Examples 1 and 2 outside the present invention were:
It can be seen that the photoconductors of Examples 1 to 12 according to the present invention are all good, while the characteristics are poor in any of the initial potential, the potential after 100,000 copies, the amount of depletion, and the image, and are not practical.

[0143]

According to the present invention, the surface hardness is high, the abrasion resistance, the scratch resistance and the interlayer adhesion are high, and the electrophotographic characteristics during repeated use are stable even under high temperature and high humidity. It is possible to develop an electrophotographic photoreceptor that can be obtained in use, and to provide an image forming method, an image forming apparatus, and a process cartridge using the photoreceptor.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an image forming apparatus equipped with an electrophotographic photosensitive member of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Photosensitive drum (or photoreceptor) 11 Exposure part using light emitting diode etc. 12 Charging device 13 Image exposing device 14 Developing device 17 Paper feed roller 18 Transfer roller (transfer device) 19 Separation brush (separator) 20 Fixing device 21 Discharge roller 22 Cleaning device 30 Removable process cartridge in which photoconductor, charging device, transfer device / separator and cleaning device are integrated.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Tetsu Uchino 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H068 AA03 AA04 AA16 BB32 BB33 BB49 CA06 FA01 FA03 FA07 FA27 FB01 FB07 FB08 FC01 FC05 FC08 FC15 4J035 BA06 CA01M CA051 CA09M CA101 CA111 CA151 CA18M CA181 CA19M CA191 CA20M CA201 CA22M CA26M CA261 FB10

Claims (9)

[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 structural unit having a charge transporting property and contains a siloxane-based resin having a crosslinked structure. And an electrophotographic photosensitive member, wherein the photosensitive layer has a silane monomer content of 500 ppm or less. 2. The electrophotographic photoreceptor according to claim 1, wherein the siloxane-based resin having a crosslinked structure is a siloxane-based resin having a structure represented by the following general formula (1). Formula (1) -Si-Y- (X) _n (wherein, X is a structural unit having charge transport performance, and Y is a divalent or higher atom or group excluding adjacent bonding atoms (Si and C). And n represents an integer of 1 or more.) 3. The electrophotographic photoreceptor according to claim 1, wherein said surface layer contains colloidal silica. 4. The electrophotographic photoreceptor according to claim 1, wherein the silane monomer is methyltrimethoxysilane. 5. The electrophotographic photoreceptor according to claim 1, wherein the silane monomer is dimethyldimethoxysilane. 6. The electrophotographic photoconductor according to claim 1, wherein the photosensitive layer contains an antioxidant. 7. An electrophotographic image forming method comprising at least steps of charging, exposing, developing, and cleaning an electrophotographic photosensitive member.
7. An image forming method, comprising using the electrophotographic photosensitive member according to any one of 6. 8. An image forming apparatus having an electrophotographic photoreceptor and at least means for charging, image exposure, development and cleaning, wherein the electrophotographic photoreceptor is attached to any one of claims 1 to 6.
An image forming apparatus using the electrophotographic photoreceptor described in the above section. 9. The electrophotographic photoconductor according to claim 1, wherein the electrophotographic photoconductor and a process cartridge used in an image forming apparatus having at least means for charging, exposing, developing, and cleaning are used. And charger, image exposure device,
A process cartridge having one of a developing unit and a cleaning unit in combination, and being designed to be freely inserted into and removed from the image forming apparatus.