JPH05181298A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To provide an electrophotographic sensitive body with which no abnormal picture image is produced even after storing in an oxidizing environment by sticking an antioxidant on the surface of the photosensitive body. CONSTITUTION:Deterioration of a photosensitive body, especially in the initial stage of using, is prevented by sticking an antioxidant on the surface of the photosensitive body containing an org. material as a structural component. To stick an antioxidiant on the surface of a photosensitive body, various methods may be used, for example, that powder of the antioxidant is directly deposited on the surface of the photosensitive body or the antioxidant is formed into microcapsules and then directly deposited. Or these powder or capsules are stuck by electrostatic force, or the antioxidant is dissolved in a solvent and then applied on the surface of the photosensitive body. As for the antioxidant, any antioxidant, UV absorbent, or photostabilizer for plastics, rubbers, oils or fats, or well-known antioxidants can be used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoconductor in which the photoconductor is prevented from being deteriorated in a storage state before use and in the initial stage of use.

[0002]

2. Description of the Related Art For electrophotographic photoreceptors, Se, Cd
Inorganic materials such as S and ZnO have been used, but in recent years, electrophotographic photoreceptors using organic materials exhibiting properties comparable to those have been developed and put into practical use. This advantage includes low cost and mass productivity, but deterioration of the material cannot be avoided because it is an organic substance. On the other hand, an undercoat layer, a protective layer, and the like are provided regardless of whether the material is an inorganic material or an organic material. However, since most of them are partially provided with an organic material, the deterioration of the material is unavoidable. Although much is not known about the deterioration mechanism of such a material, it is possible that it is caused by light irradiation, passage of electrons, reaction gas (NOx, SOx, O ₃ etc.). It is known to add a specific antioxidant to the photosensitive layer for the purpose of preventing such deterioration of the material, especially oxidation. For example, JP-A-57-122444 and JP-A-6-
1-156052, JP-A-62-265666, JP-A-63-18356, and JP-A-64-44551. However, in these inventions, the photosensitive layer contains an antioxidant, and from the viewpoint of storage, the antioxidant in the photoconductor is oxidatively deteriorated during the storage period of the photoconductor and cannot be stored. On the contrary, if an excessive amount of antioxidant is added to the photoreceptor, it adversely affects the electrostatic characteristics during its use, and improvement in this respect has been strongly desired.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photosensitive member which does not generate an abnormal image even after being stored in an oxidizing environment. Another object of the present invention is to
An object of the present invention is to provide an electrophotographic photosensitive member that does not cause deterioration of the photosensitive member in the initial stage of use. Still another object of the present invention is to provide an electrophotographic photosensitive member which can realize an inexpensive and effective storage state. Still another object of the present invention is to provide an electrophotographic photosensitive member which can always realize effective storage regardless of the storage form.

According to the present invention, there is provided an electrophotographic photoreceptor having an antioxidant attached to the surface of the photoreceptor. That is, the electrophotographic photosensitive member, particularly the electrophotographic photosensitive member including an organic material as a constituent element, has an environmental characteristic, especially a reactive gas (N
Ox, SOx, O ₃ etc.) may cause a decrease in chargeability or an abnormal image. The cause of this has not been clarified, but it is presumed to be accompanied by deterioration of the material. On the other hand, as described above, it is known to add an antioxidant to the photosensitive layer in order to prevent such oxidative deterioration of the photoreceptor, but when the antioxidant is stored in an oxidizing environment, the antioxidant is oxidized.・ If the photosensitive layer is deteriorated and adversely affects the electrostatic properties when the photoconductor is actually used, or if a large amount of an antioxidant is added to the photoconductive layer to improve the storage stability, the electrostatic potential during use may cause a residual potential, for example. Side effects such as the occurrence of

The present inventors have found that the above-mentioned problems can be solved by attaching an antioxidant to the surface of the photoconductor, and further, the deterioration of the photoconductor at the beginning of use can be prevented, and the present invention is completed. I arrived. Therefore, according to the present invention, the photoconductor can be stored inexpensively and effectively without using an expensive photoconductor storage method (for example, a photoconductor storage container sealed with an inert gas). In addition, regardless of the storage form of the photoconductor (inside or outside of the actual machine, the cassette, the degree of sealing of the storage container, etc.), effective storage is always possible. As a method of attaching such an antioxidant to the electrophotographic photoreceptor, a method of attaching the antioxidant powder to the surface of the photoreceptor as it is and attaching it, or attaching a microencapsulated antioxidant to the surface of the photoreceptor How to attach,
Antioxidant powder or microencapsulated antioxidant is attached to the photoconductor by electrostatic force, a method of dissolving the antioxidant in a suitable solvent and applying it to the surface of the photoconductor by a suitable method, followed by drying and adhering , And so on.

According to the present invention, as another means for adhering the antioxidant to the surface of the photoconductor, a method using a member containing a sublimable antioxidant in an apparatus capable of carrying out an electrophotographic process is also applied. it can.

A member containing a sublimable antioxidant will be described. This is not included in a usual electrophotographic process and is presented for the first time in the present invention, but if it can be installed without utilizing the space in the electrophotographic process and hindering the operation of the process. The shape, color, etc. are not specified. The member used in the present invention can be used without any particular specification as long as it satisfies the above conditions and contains a sublimable antioxidant. By using the member of the present invention, the problem which has been a problem in the conventional electrophotographic process can be solved. The method and construction of the (anti-fatigue) member of the present invention will be described below.

The material used as the base of the member of the present invention can contain a sublimable antioxidant, and is stable to a certain extent under various environments (it does not have to break itself). For example, it is not specified.
Among them, in consideration of the sublimability of the antioxidant, those having a large specific surface area are preferably used, and those having a porous surface, such as generally-known foam materials, are preferably used. Foaming materials include polystyrene foam, rigid urethane foam, soft urethane foam, polyethylene foam, urea foam, and other foamed plastics: rigid foam rubber, foamed chloroprene rubber and other foamed rubber: lightweight cellular concrete panel and other foamed concrete: foamed aluminum, etc. Foam metal or natural rubber, SBR, chloroprene rubber, polypropylene, polyethylene, EPDM,
EVA, polystyrene, polyvinyl chloride, 6-nylon, polycarbonate, PET, PBT, modified PPO, etc., as a foaming agent, azodicarbonamide, azobisisobutyronitrile, dinitrosopentamethylenetetramine, 4,4'oxybis Benzene sulfonyl hydrazide, paratoluene sulfonyl hydrazide, etc. are added and foamed, etc. are mentioned, but if it is possible to contain an antioxidant and it is stable to some extent in various environments, it is specified. Not something. The member of the present invention can be formed by including a sublimable antioxidant in forming these. Specific examples of the sublimable antioxidant are shown in Table 10 below.

Further, according to the present invention, there is provided a method for preventing characteristic deterioration of an electrophotographic photosensitive member, characterized in that the surface of the electrophotographic photosensitive member installed in a copying machine is treated with a member containing an antioxidant. To be done.

Examples of the member containing an antioxidant include a sheet-shaped member such as electrophotographic paper and a cleaning member. First, an electrophotographic paper, which is a typical example of a sheet member, will be described.

The electrophotographic paper is a plain paper used as an output of a copying machine, a printer, a fax machine or the like, but in the present invention, the printing may or may not be normal. That is, when printing is possible, it may be used as a normal electrophotographic paper. or,
When printing is impossible, it may be used as a cleaning tape of a tape recorder, for example. Therefore, the electrophotographic paper used in the present invention is of a form that can be passed through the copying process without causing any trouble such as scratching the photosensitive member or damaging the transport roller. As long as it is contained on the surface and / or inside, it can be used without being specified. By using the electrophotographic paper of the present invention, effects (stability against repeated use, stability to the environment, prevention of abnormal images) that cannot be obtained with the conventional electrophotographic paper (plain paper) can be obtained. The method of using the electrophotographic paper of the present invention will be described. When printing is impossible as described above, it may be used intermittently, for example, one out of every 100 sheets, and when printing is normal, as usual. It can be used continuously (used as plain paper) or intermittently.

The method for producing the electrophotographic paper of the present invention will be described below. As described above, the electrophotographic paper used in the present invention is a form that can be passed through the copying process without causing a defect such as scratching the photosensitive member or damaging the conveying roller, and prevents oxidation. Any agent containing an agent on the surface and / or inside can be used without any particular specification. The method of incorporating the antioxidant is roughly classified into two methods. One is a method in which the material (pulp or the like) is filled with an antioxidant before the electrophotographic paper is made and the paper is made. The other is after papermaking,
This is a method of coating the surface with a coating liquid containing an antioxidant. In the former, clay, clay, talc, agarite, lime carbonate, lime sulfate, barium sulfate, titanium white, zinc sulfide, etc. are usually added to the fiber (pulp) as a filler and added by a beater. At this time, an antioxidant is added at the same time or before or after, or before or after the dyeing process of pulp (may not be performed) or at the same time, and the paper is made by filtering with a paper machine. The antioxidant is preferably added immediately before papermaking. The latter is usually prepared by applying various coating solutions to a base paper using a brush coater, a roll coater, an airbrush coater, a machine coater, cast coating or the like, and drying the coating solution. The antioxidant is contained in these coating solutions and coated by coating. At this time, the coating may be performed on one side, but it is preferable that the coating is performed on both sides. When coating several layers, it is preferable to add an antioxidant to the surface layer.

Next, the cleaning blade will be described. The cleaning blade is generally made of a rubber-based elastic material, which is adhered and fixed to a supporting metal member made of a rigid material such as metal, and the supporting metal member is attached to a cleaning device inside the image forming apparatus and the leading edge of the cleaning blade is attached. Is pressed against the surface of the photoconductor to remove the toner, developer, etc. on the surface. The cleaning blade used in the present invention can be used without any particular specification as long as it can be used in the above-mentioned usage and contains an antioxidant. By using the cleaning blade of the present invention, the problems that have been a problem in the conventional electrophotographic process can be solved. The configuration and the method for producing the cleaning blade of the present invention will be described below. The material used for the cleaning blade of the present invention may be a material used for general cleaning blades, and urethane resin, silicone resin, NBR, SBR, etc. are mainly used as the main material, but they are sufficiently mixed with these materials. The following compounds can be mixed within the range where they can be dissolved. Specific examples of these compounds include unsaturated polyester resins, saturated polyester resins,
Epoxy resins, esters of these with (meth) acrylic acid, polyurethane resins, diallyl phthalate resins,
Ketone resin, alkyd resin, phenol resin, rosin-modified phenol resin, rosin ester, maleic acid-modified rosin ester, urea resin, melamine resin, polyamide resin, styrene- (meth) acrylic acid copolymer or its ester, poly (meth) acrylate, petroleum resins C ₁ -C _9, hydrogenated petroleum resin, polybutadiene, natural or synthetic rubber, polyethylene, polypropylene, ethylene - vinyl acetate copolymer resins, polyvinyl alcohol,
Wax etc. are mentioned.

The material of the cleaning blade of the present invention is not limited to the above-mentioned materials, but is specified as long as it can contain an antioxidant and can fulfill the function of the cleaning blade. Not something. The cleaning blade of the present invention is formed by including an antioxidant in the material at the time of forming the cleaning blade by using these materials or other materials or after forming the cleaning blade and adding the antioxidant by an appropriate treatment. You can Further, in the present invention, the cleaning member may be incorporated in the process kit described below. A process kit is a single device (component) that contains a photoconductor and also includes a charging / exposure, development, transfer, and cleaning unit. Incorporating the cleaning blade of the present invention into this process kit
Significantly, if, for example, the process is used in the process and problems such as photoreceptor and blade wear occur, the process kit may simply be replaced. At this time, since the blade is new, the effect of the present invention can be further enhanced as compared with a process that does not use a normal process kit.

Next, the antioxidants that can be used in the present invention are shown. As the antioxidant that can be used in the present invention, plastic, rubber, petroleum, oil and fat antioxidants, ultraviolet absorbers,
As the light stabilizer, all known materials can be used, but in particular, a material selected from the following compound group can be preferably used.

(1) Phenols described in JP-A-57-122444, phenol derivatives described in JP-A-60-188956, and JP-A-63-18356.
Bindered phenols described in Japanese Patent Publication.

(2) Paraphenylenediamines described in JP-A-57-122444, JP-A-60-188
Paraphenylenediamine derivatives described in 956 and paraphenylenediamines described in JP-A-63-18356.

(3) Hydroquinones described in JP-A-57-122444, hydroquinone derivatives described in JP-A-60-188956, and JP-A-63-1
Hydroquinones described in 8356.

(4) Sulfur compounds described in JP-A-57-188956 and organic sulfur compounds described in JP-A-63-18356.

(5) Organic phosphorus compounds described in JP-A-57-122444 and organic phosphorus compounds described in JP-A-63-18356.

(6) Hydroxyanisoles described in JP-A-57-122444.

(7) Piperidine derivatives and oxopiperazine derivatives having a specific skeleton structure described in JP-A-63-18355.

[0023] (8) Carotenes, amines, tocopherols, Ni (II) complexes, sulfides and the like described in JP-A-60-188956.

(9) US Pat. No. 1968906 and J. Am. Chem. Soc. 55, 1224 (1
933) and a compound represented by the following general formula (I) (chemical formula 1).

(In the formula, R _{1 to} R ₄ are each a hydrogen atom, a halogen atom, a viroxy group, or a substituent. Is an unsubstituted alkyl group, alkenyl group, aryl group, cycloalkyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, also substituted amino group, imino group, heterocyclic group, sulfoxide group, sulfonyl group, acyl group, Represents an azo group. )

(10) A compound represented by the following general formula (II) (formula 2).

(Wherein R ₁ , R ₂ , R ₃ and R ₄ are each a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl) Group, substituted or unsubstituted cycloalkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, alkylthio group, arylthio group, alkylamino group, arylamino group, acyl group,
Alkylacylamino group, arylacylamino group, alkylcarbamoyl group, arylcargimoyl group, alkylsulfonamide group, arylsulfonamide group, alkylsulfamoyl group, arylsulfamoyl group,
Alkylsulfonyl group, arylsulfoni Group, an alkyloxycarbonyl group, an aryloxycarbonyl group, an alkylacyloxy group, an arylacyloxy group, a silyl group or a heterocyclic group. However,
At least one of R ₁ , R ₂ , R ₃ , and R ₄ is a group having a total number of carbon atoms of 4 or more. )

(11) A compound represented by the following general formula (III) (chemical formula 3).

(In the formula, R ₅ is —C—CnH ₂ n + _1- m (R ₉ ) m
R ₆ represents a substituted or unsubstituted alkyl group having 4 to 20 carbon atoms, an aryloxy group, an alkoxy group, a cycloalkyl group, an aryl group, an aralkyl group, or R ₅ , and is bonded to R _9. Although a ring having 5 to 10 carbon atoms may be formed, R ₇ and R ₈ are not hydrogen at the same time, and R ₉ is a substituted or unsubstituted aryl group, arylthio group, aryloxy group, Arylacylamino group, arylcarbamoyl group, arylsulfonyl group, aryloxycarbonyl group,
It represents an arylacyloxy group, an arylamino group, an arylsulfonamide group, an arylsulfonyloxy group, n represents 1 to 5, and m represents 1 or 2. ),

(12) A compound represented by the following general formula (IV)

(Wherein Ar ₁ and Ar ₂ are substituted or unsubstituted aryl groups, arylthio groups, and Represents a hydroxyl group, a benzyl group, a phthalimido group,
R ₁₀ and R ₁₁ represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, an alkenyl group, an alkoxy group, an alkylthio group, an acyl group, an alkylamino group or an alkylcarbamoyl group. )

(13) A compound represented by the following general formula (V)

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ ,
R ₇ and R ₈ are each a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted Alkoxy group, substituted or unsubstituted aryloxy group, alkylthio group, arylthio group, alkylamino group, arylamino group, acyl group, alkylacylamino group, arylacylamino group, alkylcarbamoyl group, arylcargimoyl group, alkyl Sulfonamide group, aryl sulfonamide group, al It represents a kilsulfamoyl group, an arylsulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, an alkylacyloxy group, an arylacyloxy group, a silyl group or a heterocyclic group.

(14) A compound represented by the following general formula (VI)

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ ,
R ₇ and R ₈ are each a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted Alkoxy group, substituted or unsubstituted aryloxy group, alkylthio group, arylthio group, alkylamino group, arylamino group, acyl group, alkylacylamino group, arylacylamino group, alkylcarbamoyl group, arylcargimoyl group, alkyl Sulfonamide group, aryl sulfonamide group, al It represents a kilsulfamoyl group, an arylsulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, an alkylacyloxy group, an arylacyloxy group, a silyl group or a heterocyclic group.

(15) A compound represented by the following general formula (VII)

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ ,
R ₇ is a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy, respectively. Group, substituted or unsubstituted aryloxy group, alkylthio group, arylthio group, alkylamino group, arylamino group, acyl group, alkylacylamino group, arylacylamino group, alkylcarbamoyl group, arylcargimoyl group, alkylsulfonamide Group, arylsulfonamide group, alk It represents a rusulfamoyl group, an arylsulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, an alkylacyloxy group, an arylacyloxy group, a silyl group or a heterocyclic group.

(16) The following general formula (VIII)
The compound represented by.

(Wherein R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are each a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted An aryl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, an alkylthio group, an arylthio group, an alkylamino group, an arylamino group, an acyl group,
Alkylacylamino group, arylacylamino group, alkylcarbamoyl group, arylcargimoyl group , An alkyl sulfonamide group, an aryl sulfonamide group, an alkylsulfamoyl group, an arylsulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group,
It represents an alkyloxycarbonyl group, an aryloxycarbonyl group, an alkylacyloxy group, an arylacyloxy group, a silyl group or a heterocyclic group.

(17) A compound represented by the following general formula (IX)

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ ,
R ₇ and R ₈ are each a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted Alkoxy group, substituted or unsubstituted aryloxy group, alkylthio group, arylthio group, alkylamino group, arylamino group, acyl group, alkylacylamino group, arylacylamino group, alkylcarbamoyl group, arylcargimoyl group, alkyl Sulfonamide group, arylsulfonamide group, alkylsulfamoyl group, arylsulfamoyl group, alkylsulfonyl group, arylsulfonyl group, alkyloxycarbonyl group, aryloxycarbonyl group, alkylacyloxy group, arylacyloxy group, It represents a group or a heterocyclic group. Specific examples of the compounds represented by formulas (I) to (IX) are shown below, but it goes without saying that the compounds are not limited to these. Further, Table 10 also shows specific examples of the sublimable antioxidant. In the present invention, as a means for adhering these antioxidants to the surface of the photoconductor, other than the above method, for example, the antioxidant may be used in the toner or its surface, the carrier surface, or the powder in the developer. The method of incorporating into the above can also be applied. [Specific Examples of Compounds of General Formula (I)]

[Table 1- (1)]

[Table 1- (2)] [Specific Examples of Compounds of General Formula (II)]

[Table 2- (1)]

[Table 2- (2)]

[Table 2- (3)]

[Table 2- (4)]

[Table 2- (5)]

[Table 2- (6)]

[Table 2- (7)]

[Table 2- (8)]

[Table 2- (9)]

[Table 2- (10)]

[Table 2- (11)]

[Table 2- (12)]

[Table 2- (13)]

[Table 2- (14)]

[Table 2- (15)]

[Table 2- (16)]

[Table 2- (17)]

[Table 2- (18)]

[Table 2- (19)]

[Table 2- (20)]

[Table 2- (21)]

[Table 2- (22)]

[Table 2- (23)]

[Table 2- (24)]

[Table 2- (25)]

[Table 2- (26)]

[Table 2- (27)]

[Table 2- (28)]

[Table 2- (29)]

[Table 2- (30)]

[Table 2- (31)]

[Table 2- (32)] [Specific Examples of Compounds of General Formula (III)]

[Table 3- (1)]

[Table 3- (2)]

[Table 3- (3)]

[Table 3- (4)]

[Table 3- (5)]

[Table 3- (6)]

[Table 3- (7)] [Specific Examples of Compounds of General Formula (IV)]

[Table 4- (1)]

[Table 4- (2)] [Specific Examples of Compounds of General Formula (V)]

[Table 5- (1)]

[Table 5- (2)]

[Table 5- (3)]

[Table 5- (4)]

[Table 5- (5)]

[Table 5- (6)]

[Table 5- (7)]

[Table 5- (8)]

[Table 5- (9)]

[Table 5- (10)]

[Table 5- (11)]

[Table 5- (12)]

[Table 5- (13)] [Specific Examples of Compounds of General Formula (VI)]

[Table 6- (1)]

[Table 6- (2)] [Specific Examples of Compounds of General Formula (VII)]

[Table 7- (1)]

[Table 7- (2)]

[Table 7- (3)]

[Table 7- (4)]

[Table 7- (5)]

[Table 7- (6)]

[Table 7- (7)] [Specific Examples of Compounds of General Formula (VIII)]

[Table 8- (1)]

Example 37 The structure of the photoconductor is shown above. On an φ80 mm Al drum, an undercoat layer coating solution having the following composition, a charge generating layer coating solution,
The charge transport layer coating liquid is sequentially applied and dried to give 0.2
an undercoat layer having a thickness of 0.3 μm and a charge generation layer having a thickness of 0.3 μm
A charge transport layer having a thickness of μm was formed to prepare a photoreceptor of the present invention. [Undercoat layer coating liquid] Methanol 80 parts n-Butanol 20 parts Alcohol-soluble nylon (Alamine CM-8000, manufactured by Toray) 3 parts Alcohol-soluble nylon is dissolved in a methanol / n-butanol mixed solvent having the above composition, and the undercoat is applied. A layer coating solution was prepared. [Coating liquid for charge generation layer] 2 parts of azo pigment having the following structure

[Chemical 15] Cyclohexane 100 parts Tetrahydrofuran 50 parts The above components were mixed and ball milled for 20 hours to obtain a coating liquid. [Charge transport layer coating liquid] Dichloromethane 83 parts Polycarbonate (Panlite K-1300, manufactured by Teijin Chemicals) 10 parts Charge transport material (chemical formula 16) 7 parts Silicon oil (KF-50, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.002 parts

[Chemical 16] Polycarbonate, charge transport material, and silicone oil were dissolved in dichloromethane to prepare a charge transport layer coating liquid. Next, the structure of the electrophotographic paper is shown. Sulfurous acid and soda wood pulp (500 g each) were placed in a beater and water was added to adjust the concentration to 4%. To this, 250 g of clay and sodium rosin acid solution were sequentially added, 5 g of aluminum sulfate was added, and finally Compound No (II)- Add 10 g of 124 antioxidants,
Beaten for 3 hours. The above liquid was filtered using a Fourdrinier paper machine, pressed, dried and then cut into a suitable size. The photoreceptor was subjected to a running test of 10,000 sheets using a copying machine RICOH IMAGIO 320 (25 ° C., 6
0% RH). At this time, the electrophotographic paper was used as a running paper. The evaluation was performed on the 10000th image.

Comparative Example 5 The electrophotographic paper of Example 1 was evaluated in exactly the same manner except that no antioxidant was added (photoreceptor was the same). When the electrophotographic paper of Example 37 was used, it was a normal image, but in Comparative Example 5, the 10000th image had white spots.

Example 38 The constitution of the photoconductor is shown below. On a polyethylene terephthalate film vapor-deposited with Al, a coating solution for an undercoat layer having the following composition, a coating solution for a charge generation layer, and a coating solution for a charge transport layer were sequentially formed,
After coating and drying, each undercoat layer is 0.3μm thick, 0.2μ
An m-thick charge generation layer and a 19 μm-thick charge transport layer were formed. [Undercoat layer coating liquid] Water 35 parts Methanol 50 parts Water-soluble polyvinyl alcohol (S-REC W-201, Sekisui Chemical Co., Ltd.) 15 parts Water-soluble polyvinyl butyral is dissolved in the above composition water / methanol mixed solvent to form an undercoat layer coating solution. A working fluid was created. [Charge generation layer coating liquid] 5 parts of azo pigment having the following structure

[Chemical 17] Polyvinyl butyral (Sekisui Chemical Co., Ltd., S-REC BM0-S) 2 parts Cyclohexanone 300 parts 2-butanone 200 parts The above components were mixed and ball-milled for 36 hours to obtain a coating liquid. [Charge transport layer coating liquid] 1,2-dichloroethane 83 parts Polyester (Vylon 200, manufactured by Toyobo) 10 parts Charge transport material (chemical formula 18) 7 parts Silicon oil (KF-54, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.002 parts Polyester, charge transport material and silicone oil were dissolved in dichloroethane to prepare a charge transport layer coating solution.

[Chemical 18] The photosensitive member thus prepared was joined to the belt to obtain a mounting photosensitive member. Next, the structure of the electrophotographic paper is shown. Example 3
The antioxidant used for the electrophotographic paper in No. 7 is compound N
o (II) -201 was prepared in the same manner except that the antioxidant was replaced.

Comparative Example 6 An electrophotographic paper was prepared and evaluated in the same manner except that no antioxidant was added (photoreceptor was the same as in Example 37). The photoconductor is mounted on a copying machine Ricoh Mai Recopy M5,
A running test was performed on 3000 sheets under the environment of 90 ° C. and 90% RH. The electrophotographic paper of Example 38 is plain paper 5
One out of every zero. In the 3001st image,
When the electrophotographic paper of Example 38 was used, it was good regardless of the first sheet, but in Comparative Example 6, scumming occurred.

Example 39 The constitution of the photoconductor will be described below. After forming an undercoat layer on an φ40 mm Al drum under the following conditions, a coating liquid for charge generation layer, a coating liquid for charge transport layer, a coating liquid for intermediate layer, a coating liquid for protective layer having the following composition Are sequentially applied and dried to 0.3 μm each.
m charge generation layer, 20 μm charge transport layer, 0.2 μm
A thick intermediate layer and a 2 μm protective layer were formed. [Conditions for forming undercoat layer] A conductive substrate is used as an anode, and 15%
Electrolytic treatment was performed for 15 minutes in a sulfuric acid solution to form an anodized film on the conductive substrate. Further, this substrate was added at a concentration of 6 g / l,
The hole was sealed by immersing it in a nickel acetate solution having a liquid temperature of 70 ° C. for 5 minutes. The oxide film formed on the substrate had a thickness of 6 μm. [Coating liquid for charge generation layer] ε-type copper phthalocyanine 3 parts Polysulfone (manufactured by Nissan Kagaku Co., Ltd., P-1700) 1 part Cyclohexane 60 parts 2-Butanone 40 parts The above components are mixed and ball milled for 30 hours. Was used as the coating liquid. [Coating Liquid for Charge Transport Layer] Dichloromethane 100 parts Polycarbonate (Lexan 141, manufactured by GE) 10 parts Charge transport material 10 parts Silicon oil 0.2 parts Dicarbonate in polycarbonate, charge transport material, dissolved in silicon oil Charge transport layer A coating liquid was prepared.

[Chemical 19] [Intermediate layer coating liquid] Soluble nylon (manufactured by Toray Industries, Inc., Alamin CM-4000) 3 parts Methanol 100 parts [Intermediate layer coating liquid] St-MMA-2-HEMA copolymer 10 parts Tin oxide ( Mitsubishi Metals) 5 parts Toluene 100 parts Cellosolve acetate 60 parts Methyl butyl ketone 40 parts After the above ball milling for 60 hours, 2 parts of polyisocyanate (Sumijour HT, manufactured by Sumitomo Bayer) was added to obtain a coating solution. Next, the structure of the electrophotographic paper is shown. The antioxidant used for the electrophotographic paper of Example 37 was compound No.
(III) -6 was prepared in the same manner except that the antioxidant was replaced with the antioxidant.

Comparative Example 7 An electrophotographic paper was prepared and evaluated in the same manner except that no antioxidant was added (photoreceptor was the same as in Example 39). Laser printer Ricoh LP10
It was mounted on a modified 60-SP3 machine, and 5000 sheets were run under the environment of 30 ° C. and 90% RH. At this time, the electrophotographic paper of Example 3 was kept flowing as a running paper. In the evaluation, the drum evaluation surface potential of the developing section after the completion of the first 5000 sheets was measured with an electrometer and the following results were obtained.

[Table 15]

Example 40 The constitution of the photoconductor is shown below. On the Ni-deposited Mylar film, a charge transport layer coating solution, a charge generation layer coating solution, and a protective layer coating solution having the following compositions were sequentially coated and dried to form a charge transport layer having a thickness of 20 μm. A 5 μm charge generating layer and a 2 μm thick protective layer were formed. [Charge transport layer coating liquid] Chloroform 9 parts Polyester (Vylon 200, Toyobo) 1 part Charge transport material (Chemical formula 20) 1 part Silicon oil (KF-50, Shin-Etsu Chemical Co., Ltd.) 0.02 parts Chloroform polyester, charge A transport material and silicone oil were dissolved to prepare a charge transport layer coating liquid.

[Chemical 20] [Coating liquid for charge generation layer] 6 parts of azo pigment having the following structure

[Chemical 21] Polyvinyl butyral (Sekisui Chemical Co., Ltd. S-REC BL-1) 1 part Cyclohexane 200 parts 2-butanone 50 parts The above components were mixed and ball-milled for 20 hours to obtain a coating liquid. [Coating liquid for protective layer] Styrene-methyl methacrylate-2-hydroxyethyl methacrylate-trichloroethyl methacrylate copolymer 10 parts Conductive titanium oxide 8 parts Toluene 100 parts n-Butanol 50 parts The above are mixed and ball milling 36 hours. The coating solution was used. A belt joining process was performed on the photoconductor thus prepared to prepare a photoconductor for mounting. Next, the structure of the electrophotographic paper is shown. The same preparation was carried out except that the antioxidant used in the electrophotographic paper of Example 37 was replaced with the antioxidant of compound No (IV) -1.

Comparative Example 8 An electrophotographic paper was prepared and evaluated in the same manner except that no antioxidant was added (photoreceptor was the same as in Example 39). Laser printer Ricoh LP33
20-SP4 was mounted on a column modified so that it could be used by positive charging, and 3000 sheets were run under the environment of 15 ° C. and 30%. The electrophotographic paper of Example 40 was plain paper, one out of every 100 sheets. In the 3000th image, when the electrophotographic paper of Example 40 was used, it was as good as the first image, but in the case of Comparative Example 8, scumming occurred.

Example 41 The constitution of the photoconductor is shown below. On a φ80 mm Al drum, a charge generation layer coating liquid, a charge transport layer coating liquid, and an intermediate layer coating liquid having the following compositions were sequentially applied and dried to each 0.2
μm thick charge generation layer, 20 μm thick charge transport layer, 0.2
A μm thick intermediate layer was formed. Further, the following protective layer was formed thereon by the vacuum thin film forming method. [Coating liquid for charge generation layer] 2 parts of azo pigment having the following structure

[Chemical formula 22] Phenoxy resin (VYHH manufactured by UCC) 1 part Cyclohexanone 150 parts 2-Butanone 150 parts The above mixture was mixed and subjected to ball milling for 36 hrs to obtain a coating liquid. [Charge transport layer coating liquid] Tetrahydrofuran 100 parts Pola carbonate (Panlite C-1400, manufactured by Teijin Chemicals) 10 parts Charge transport material (chemical formula 23) 9 parts Silicon oil (KF-50, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.1 Part Polycarbonate, charge transport material, and silicone oil were dissolved in tetrahydrofuran to prepare a charge transport layer coating solution.

[Chemical formula 23] [Intermediate layer coating liquid] Soluble nylon (Amylan CM-4000 manufactured by Toray Industries, Inc.) 2 parts Methanol 70 parts n-Butanol 30 parts [Protective layer] An ac thin film was formed by plasma CVD. Gas used: hydrogen, butadiene, carbon tetrafluoride Next, the constitution of the electrophotographic paper is shown. An electrophotographic paper was obtained by applying the following coating liquid to the base paper for coating using a roll coater at 5 μm on each side and drying. Tetrahydrofuran 100 parts U polymer (Unitika) 5 parts Compound No (III) -13 antioxidant 25 parts

Comparative Example 9 The packaging paper of Example 41 was evaluated in the same manner except that the antioxidant was removed (same photoconductor). The photoconductor prepared as described above is mounted on a copier, Recopy FT4800, and the
A running test of 8000 sheets was performed in an environment of 0 ° C. and 90%. The electrophotographic paper of Example 41 was flown once for every 80 plain papers. The 8000th image was evaluated. 80
In the 00th image, when the electrophotographic paper of Example 41 was used, it was as good as the first image, but Comparative Example 9
In the case of, image blurring occurred.

Example 42 The constitution of the photoconductor is shown below. On the Al-deposited seamless polyimide film, a charge generation layer coating solution and a charge transport layer coating solution having the following compositions are sequentially applied and dried to form a charge generation layer having a thickness of 0.3 μm and a charge transport layer having a thickness of 25 μm. Formed. [Charge generation layer coating liquid] 5 parts of azo pigment having the following structure

[Chemical formula 24] Polyvinyl butyral (Denka Butyral # 4000-1 manufactured by Denki Kagaku Kogyo KK) 1 part Cyclohexanone 300 parts The above components were mixed and subjected to ball milling for 48 hours to obtain a coating liquid. [Charge transport layer coating liquid] Toluene 320 parts Polycarbonate resin (Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.) 70 parts Charge transport material (chemical formula 25) 49 parts Silicon oil (KF-54, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.01 Part Polycarbonate, charge transport material and silicone oil were dissolved in toluene to prepare a charge transport layer coating liquid.

[Chemical 25] Next, the structure of the electrophotographic paper is shown. The following coating liquid was applied to the base paper for coating using an air knife coater at 10 μm on one side and dried to obtain an electrophotographic paper. Distilled water 190 parts Polyvinyl alcohol 5 parts Compound No (II) -135 antioxidant 20 parts The above components were mixed and dispersed to obtain a coating liquid. The photoreceptor was subjected to a running test of 5,000 sheets using a copying machine Recopy FT-2050 (25 ° C., 60% RH). At this time, the electrophotographic paper was used as a running paper so that the coated surface was on the photoreceptor side. For evaluation, the image density of the black solid portion of the 5000th image was measured with a commercially available Macbeth densitometer.

Comparative Example 10 The electrophotographic paper of Example 42 was evaluated in exactly the same manner except that no antioxidant was added, and the following results were obtained.

[Table 16]

Example 43 The constitution of the photoconductor is shown below. An undercoat layer having the following composition is formed on a φ120 mm Al drum, and a coating solution for the charge generation layer and a coating solution for the charge transport layer having the following compositions are sequentially applied and dried thereon to a thickness of 0.1 μm. Subsequent layers of
After coating and drying, each undercoat layer has a thickness of 0.1 μm, 0.2 μm
A thick charge generation layer and a 18 μm thick charge transport layer were formed. [Undercoat layer coating liquid] An undercoat layer made of SnO ₂ was formed on the substrate by a sputtering apparatus. [Charge generation layer coating liquid] 5 parts of azo pigment having the following structure

[Chemical formula 26] Polyvinyl butyral (manufactured by UCC: XYHL) 2 parts Tetrahydrofuran 400 parts Ethyl cellosolve 200 parts The above components were mixed and dispersed with an attritor for 10 hrs to give a coating liquid. [Charge transport layer coating liquid] Tetrahydrofuran 83 parts Polyarylate (U-polymer, U-100, manufactured by Unitika) 10 parts Charge transport material (Chemical formula 27) 7 parts Silicon oil 0.002 parts Polyarylate in tetrahydrofuran, charge transport material ,
Silicone oil was dissolved to prepare a charge transport layer coating liquid.

[Chemical 27] Next, the structure of the electrophotographic paper is shown. An electrophotographic paper was obtained by applying the following coating liquid on one side of the base paper for coating using an air knife coater to a thickness of 7 μm and drying. Distilled water 200 parts Polyvinyl alcohol 3 parts Compound No (II) -63 antioxidant 20 parts The above components were mixed and dispersed to obtain a coating liquid.

Comparative Example 11 The electrophotographic paper of Example 43 was evaluated in the same manner except that the antioxidant was omitted (same photoconductor). The photoconductor was subjected to a running test on 5000 sheets using a copying machine, Art 5330 (15 ° C., 30% RH). At this time, one sheet of the above electrophotographic paper was flowed so that the coated surface was on the side of the photoconductor. The evaluation was the image evaluation of the 5000th sheet. When the electrophotographic paper of Example 43 was used, the 5000th sheet gave a good image as in the case of the 1st sheet, but in the case of Comparative Example 11, the white solid part was stained.

Example 44 The constitution of the photoconductor will be described below. A coating liquid for a charge generation layer and a coating liquid for a charge transport layer having the following compositions were sequentially applied and dried on an Al vapor-deposited polyethylene terephthalate film to form a 0.2 μm thick charge generation layer and a 24 μm charge transport layer, respectively. Formed. [Charge generation layer coating liquid] 5 parts of azo pigment having the following structure

[Chemical 28] Polycarbonate (Panlite 1250 manufactured by Teijin Ltd.) 2 parts Tetrahydrofuran 500 parts The above components were mixed and dispersed by an attritor for 15 hours to obtain a coating liquid. [Charge Transport Layer Coating Liquid] Dichloromethane 75 parts Polycarbonate (Panlite K-1300, manufactured by Teijin Chemicals) 5 parts Polycarbonate (Upilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.) 5 parts Charge transport material (chemical 29) 8 parts Silicon oil (KF-50, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.1 part Polycarbonate, charge-transporting substance, and silicone oil were dissolved in dichloromethane to prepare a charge-transporting layer coating liquid.

[Chemical 29] After the above was prepared, a belt-bonding process was performed to obtain a photosensitive member for mounting. Next, the structure of the electrophotographic paper is shown. For base paper for coating,
An electrophotographic paper was obtained by coating the following coating liquid on a roll coater with a thickness of 5 μm on one side and drying. Tetrahydrofuran 200 parts Vinyl chloride-vinyl acetate copolymer 10 parts Antioxidant of compound No (II) -48 20 parts The above were mixed and dissolved to obtain a coating liquid.

Comparative Example 12 The electrophotographic paper of Example 44 was evaluated in the same manner except that the antioxidant was omitted (same photoconductor). 6000 using a device modified so that the surface potential of the photoconductor in the developing section of the copying machine Recopy FT2050 can be measured.
A running test of one sheet was performed. At this time, the electrophotographic paper was used as a running paper. Evaluation is 1st sheet and 6
The surface potential of the 000th sheet was measured and the following results were obtained.

[Table 17]

Example 45 The constitution of the photoconductor is shown below. An undercoat layer coating liquid, a charge generation layer coating liquid, and a charge transport coating liquid having the following compositions were sequentially applied to an Al drum having a diameter of 80 mm and dried, and the coating liquids each had a thickness of 0.
A 2 μm thick undercoat layer, a 0.1 μm thick charge generation layer and a 21 μm thick charge transport layer were formed. [Undercoat layer coating liquid] Water 200 parts Methanol 100 parts Polyvinyl alcohol (Denka Poval H-20, manufactured by Denki Kagaku Kogyo Co., Ltd.) 2 parts Polyvinyl alcohol is dissolved in the above composition water / methanol mixed solvent to prepare an undercoat coating liquid. Created. [Charge generation layer coating liquid] 5 parts of azo pigment having the following structure

[Chemical 30] Polyester (Vylon 300 manufactured by Toyobo Co., Ltd.) 0.5 part Cyclohexanone 300 part 4-Methyl-2-pentanone 100 parts The above components were mixed and subjected to ball milling for 36 hours to obtain a coating liquid. [Charge transport layer coating liquid] Monochlorobenzene 40 parts Polycarbonate (Iupilon Z-300, manufactured by Mitsubishi Gas Chemicals) 6 parts Charge transport material (Chemical formula 31) 5 parts Silicon oil (KF-50, manufactured by Shin-Etsu Chemical Co., Ltd.) () part Polycarbonate, a charge transport material and silicone oil were dissolved in monochlorobenzene to prepare a charge transport layer coating solution.

[Chemical 31] Next, the structure of the electrophotographic paper is shown. The following coating liquid was applied to the electrophotographic paper prepared in Example 41 by a roll coater in an amount of 5 μm on one side and dried to obtain an electrophotographic paper. Methanol 100 parts Alcohol-soluble nylon (Toray: CM-8000) 10 parts Antioxidant of compound No (II) -2 30 parts The above components were mixed and dissolved to obtain a coating liquid.

Comparative Example 13 The electrophotographic paper of Example 45 was evaluated in the same manner except that the antioxidant was omitted (same photoconductor). The photoconductor was subjected to a running test of 5,000 sheets using a copying machine Recopy FT-4820 (25 ° C., 40%). At this time, one of the 100 sheets of plain paper was flowed so that the coated surface was on the photoreceptor side. Evaluation is 1st sheet and 5
The image density of the solid black portion of the 000th image was measured with a commercially available Macbeth densitometer, and the following results were obtained.

[Table 18]

Example 46 On a polyethylene terephthalate film on which aluminum was vapor-deposited, a charge generation layer coating solution having the following composition and a charge transport layer coating solution were sequentially applied and dried to form a charge generation layer having a thickness of 0.2 μm and a charge generation layer respectively. A 22 μm thick charge transport layer was formed to prepare an electrophotographic photoreceptor of the present invention. [Charge generating layer coating liquid] 4 parts of the charge generating substance having the following structural formula

[Chemical 32] Cyclohexanone 200 parts 2-Butanone 150 parts [Charge transport layer coating liquid] Charge transport material having the following structural formula 6 parts

[Chemical 33] Polyarylate (U-100, manufactured by Unitika Ltd.) 9 parts Tetrahydrofuran 80 parts The above-prepared photoreceptor was belt-joined to obtain a mounting photoreceptor. Next, the configuration of the cleaning blade will be described. Compound NO (I) -5 30 parts NBR 100 parts Sulfur 3 parts The above components were kneaded with a two-roll mill, heat-crosslinked, and pressure-molded. The photoconductor and the cleaning blade were placed on a copying machine RICOH FT2050, and a running test was performed on 4000 sheets at room temperature and normal humidity. The evaluation was performed on the 4000th image.

Comparative Example 14 The same evaluation as in Example 46 was carried out except that the antioxidant was not added. In the case of Example 46, 1
Similar to the first sheet, the 4,000th sheet also gave a good image, but in the case of Comparative Example 14, scumming occurred.

Example 47 On a polyethylene terephthalate film provided with a Hastelloy conductive layer, a subbing layer coating solution, a charge generating layer coating solution and a charge transporting layer coating solution having the following compositions were successively applied and dried, respectively. 2 μm undercoat layer, 0.3 μm charge generation layer and 18 μm
A charge transport layer of m was formed to prepare an electrophotographic photoreceptor of the present invention. [Charge generating layer coating liquid] 4 parts of the charge generating substance having the following structural formula

[Chemical 34] Polyvinyl butyral resin 1 part (Denka Butyral # 4000-1 manufactured by Denki Kagaku Kogyo Co., Ltd.) Cyclohexanone 300 parts 2-Butanone 50 parts [Charge transport layer coating liquid] Charge transport substance of the following structural formula 9 parts

[Chemical 35] Polycarbonate (Panlite L-125, manufactured by Teijin Kasei Co., Ltd.) 10 parts Tetrahydrofuran 80 parts The above-prepared photoreceptor was belt-joined to obtain a mounting photoreceptor. Next, the configuration of the cleaning blade will be described. Compound No (II) -7 70 parts SBR 200 parts Sulfur 5 parts The above components were kneaded with a two-roll mill, heated and bridged, and pressure-molded. The photoconductor and the cleaning blade were mounted on an apparatus modified so that a surface electrometer could be set immediately before the developing section of the copying machine Ricoh FT2050. A running test of 5,000 sheets was performed in an environment of 30 ° C. and 90% RH, and the surface potentials of the black solid portions of the first sheet and the 5,000th sheet were measured.

Comparative Example 15 The same results were obtained as in Example 47 except that the antioxidant was removed from the cleaning blade, and the following results were obtained.

[Table 19]

Example 48 On a φ60 Al cylindrical support, a charge generating layer coating solution and a charge transporting layer coating solution having the following compositions were successively applied and dried to form a charge generating layer having a thickness of 0.2 μm and 1 respectively. After forming a charge transporting layer of .9 μm, a protective layer of 1 μm is formed by a vacuum thin film forming method,
A photoconductor was created. [Charge generating layer coating liquid] 4 parts of the charge generating substance having the following structural formula

[Chemical 36] Polyvinyl butyral (Sekisui Chemical Co., Ltd., S-REC BM-S) 0.5 part Toluylene-2,4-diisocyanate 0.1 part Cyclohexanone 400 parts 2-butanone 100 parts [Charge transport layer coating liquid] The following structural formula Charge transport material 9 parts

[Chemical 37] Polycarbonate (Panlite K-1300, manufactured by Teijin Chemicals Ltd.) 11 parts Methylene chloride 80 parts [Protective layer] A thin film was formed by plasma CVD. Gas used: hydrogen, butadiene, carbon tetrafluoride Next, the structure of the cleaning blade will be described. Urethane resin 100 parts Toluylene 2,4 diisocyanate 5 parts After mixing the above with a two-roll mill, crosslinking was carried out under heat and pressure. This was immersed in the following solution, impregnated with an antioxidant, and then dried to obtain a cleaning blade. THF 100 parts Compound No (II) -124 antioxidant 50 parts The photoconductor and the cleaning blade were mounted on a laser printer LP1060-SP3 at 15 ° C., 30% R.
6000 running tests under H environment 6
The 000th image was evaluated. (In addition, around the photoconductor of this machine is a process kit.)

Comparative Example 16 Evaluation was made in the same manner except that the antioxidant was omitted from the cleaning blade of Example 48. The image of Example 48 was good on the 6000th image as well as the first image, but in the case of Comparative Example 16, black solid white spots were generated.

Example 49 An undercoat layer coating solution, a charge generation layer coating solution and a charge transport layer coating solution having the following compositions were successively formed on the same support as in Example 48,
After coating and drying, an undercoat layer of 0.3 μm, a charge generation layer of 0.2 μm, and a charge transport layer of 20 μm were formed to prepare an electrophotographic photoreceptor of the present invention. [Subbing layer coating liquid] 25% aqueous solution of water-soluble polyvinyl butyral 50 parts (Sekisui Chemical Co., Ltd. S-REC W-201) Water 150 parts Methanol 200 parts [Charge generating layer coating liquid] Charge of the following structural formula Generated material 5 parts

[Chemical 38] Polyester (Vylon 200 manufactured by Toyobo Co., Ltd.) 2 parts Toluylene-2,4-diisocyanate 0.1 part Tetrahydrofuran 200 parts 4-Methyl-2-pentanone 300 parts [Charge transport layer coating liquid] Charge transport of the following structural formula 8 parts of substance

[Chemical Formula 39] Polycarbonate (manufactured by Teijin Chemicals Ltd., Panlite L-1250) 10 parts Tetrahydrofuran 70 parts Next, the structure of the cleaning blade will be described. Compound No (III) -6 40 parts NBR 40 parts SBR 60 parts Sulfur 2 parts After kneading the above with a two-roll mill, crosslinking was carried out under humidification and pressure to form a blade. The photoconductor and the cleaning blade are mounted on a copier Recopy FT4820,
A running test of 10,000 sheets was performed at 90 ° C. and 90% RH. For the evaluation, the density of the solid black portion of the image was measured with a commercially available Macbeth densitometer.

Comparative Example 17 The same evaluation was performed except that the antioxidant was removed from the cleaning blade of Example 49, and the following results were obtained.

[Table 20]

Example 50 On a φ80 Al cylindrical support, a charge generation layer coating solution, a charge transporting coating solution and a protective layer coating solution having the following compositions were sequentially applied and dried to obtain 0.2 μm charge. A charge transporting layer having a thickness of 20 μm and a protective layer having a thickness of 5 μm were formed to prepare an electrophotographic photoreceptor of the present invention. [Charge generating layer coating liquid] 3 parts of the charge generating substance having the following structural formula

[Chemical 40] Polyvinyl butyral (UCC, XYHL) 1 part Cyclohexanone 100 parts Tetrahydrofuran 100 parts [Charge transport green layer coating liquid] 8 parts of the charge transport substance of the following structural formula

[Chemical 41] Polyester (Vylon 200, manufactured by Toyobo Co., Ltd.) 10 parts Tetrahydrofuran 70 parts [Protection layer coating liquid] Styrene-methyl methacrylate-2-hydroxyethyl methacrylate-trifluoroethylene methacrylate copolymer 70 parts Conductive titanium oxide 90 parts Toluene 220 parts n-Butanol 60 parts Next, the structure of the cleaning blade will be described. Silicone rubber 100 parts Silica 25 parts 2,5 Dimethylperoxyhexane 1 part After kneading the above with 12 rolls, heat crosslinking was performed under pressure. This was immersed in the following solution, impregnated with an antioxidant, and then dried to obtain a blade. THF 100 parts Compound No (IV) -7 40 parts The photoconductor and the cleaning blade are used as a copying machine FT48.
Mounted on 20 and 1000 at 30 ℃, 90% RH
0 running test, 1st and 10000
The first image was evaluated.

Comparative Example 18 The same evaluation was carried out except that the antioxidant was omitted from the cleaning blade of Example 50. The image of Example 50 is 1
The first and 10,000th sheets were good, but Comparative Example 18
In the case of, the image deletion occurred on the 10000th sheet.

Example 51 On a polyethylene terephthalate film vapor-deposited with aluminum, a charge generation layer coating solution having the following composition and a charge transport layer coating solution were sequentially applied and dried to form a charge generation layer having a thickness of 0.2 μm and a charge generation layer respectively. A 22 μm thick charge transport layer was formed to prepare an electrophotographic photoreceptor of the present invention. [Charge generating layer coating liquid] 4 parts of the charge generating substance having the following structural formula

[Chemical 42] Cyclohexanone 200 parts 2-butanone 150 parts [Charge Transport Layer Coating Liquid] 7 parts of the charge transport material having the following structural formula

[Chemical 43] Polyarylate (Unitika U-100) 9 parts Tetrahydrofuran 80 parts The photoreceptor thus prepared was belt-joined to obtain a mounting photoreceptor. Next, the structure of the members will be described. Compound No (X) -1 sublimable antioxidant 50 parts AIBN 5 parts Polystyrene raw material 100 parts The above mixture is heated and melted at 100 ° C. in an extruder,
It was extruded into the air, foamed, cut, and molded into a predetermined shape and dimension. The photoconductor and the member were mounted on a copying machine FT2050, and a running test of 3000 sheets was conducted. (25
%, 60% RH). The evaluation was performed on the 3000th image.

Comparative Example 19 The same evaluation as in Example 51 was carried out except that the sublimable antioxidant was not added. When the member of Example 51 was used, a good image was provided on the 3000th sheet as in the case of the 1st sheet, but in the case of Comparative Example 19, scumming occurred.

Example 52 On a polyethylene terephthalate film provided with a Hastelloy conductive layer, a subbing layer coating solution, a charge generating layer coating solution and a charge transporting layer coating solution having the following composition were successively applied, dried and dried.
2 μm each undercoat layer, 0.3 μm charge generation layer and 1
An 8 μm charge transport layer was formed to prepare the electrophotographic photoreceptor of the present invention. [Undercoat coating liquid] Titanium dioxide 10 parts Polyester (Toyobo Co., Ltd. Byron 200) 1 part Toluylene-2,4-diisocyanate 0.2 part 2-butanone 100 parts 4-Methyl-2-pentanone 70 parts [ Charge Generating Layer Coating Liquid] 4 parts of the charge generating substance having the following structural formula

[Chemical 44] Polyvinyl butyral resin 1 part (Denka Butyral # 4000-1 manufactured by Denki Kagaku Kogyo Co., Ltd.) Cyclohexanone 300 parts 2-Butanone 50 parts [Charge transport layer coating liquid] Charge transport substance of the following structural formula 9 parts

[Chemical 45] Polycarbonate (Panlite K-1300 manufactured by Teijin Kasei Co., Ltd.) 10 parts Tetrahydrofuran 80 parts The above-prepared photoreceptor was belt-joined to obtain a mounting photoreceptor. Next, the structure of the members will be described. Compound No (X) -20 sublimable antioxidant 40 parts Polyvinyl chloride 100 parts Azodicarbonamide 5 parts The above mixture was heated and melted at 130 ° C. A hollow polypropylene container was formed by coating. The photoconductor and the members were mounted on an apparatus modified so that a surface electrometer could be set on the solid black portion of the copying machine FT2050 immediately before the developing portion. A running test of 4000 sheets was performed in an environment of 30 ° C. and 90%. For evaluation, the surface potentials of the first and 4000th sheets were measured.

Comparative Guard 20 The same evaluation was performed except that the member of Example 52 was not mounted, and the following results were obtained.

[Table 21]

Example 53 On a φ80 Al cylindrical support, a charge generation layer coating solution, a charge transport layer coating solution and a protective layer coating solution having the following compositions were successively added.
0.2 μm charge generation layer after coating and drying, 20 μm each
The charge transport layer and the protective layer having a thickness of 5 μm were formed to prepare the electrophotographic photoreceptor of the present invention. [Charge generating layer coating liquid] 3 parts of the charge generating substance having the following structural formula

[Chemical 46] Polyvinyl butyral (UCHL XYHL) 0.5 part Cyclohexanone 100 parts Tetrahydrofuran 100 parts [Charge transport layer coating liquid] 8 parts of the charge transport substance of the following structural formula

[Chemical 47] Polyester (Vylon 200 manufactured by Toyobo Co., Ltd.) 10 parts Tetrahydrofuran 70 parts [Protective layer coating liquid] Styrene-methyl methacrylate-2-hydroxyethyl methacrylate-trifluoroethylene methacrylate copolymer 70 parts Conductive titanium oxide 90 parts Toluene 220 parts n-Butanol 60 parts Next, the structure of the members will be described. Compound No (X) -16 sublimable antioxidant 30 parts Chloroprene rubber 80 parts Dinitrosopentamethylene latramine 5 parts The above mixture was heated to 120 ° C. and then molded by pressure molding. The photoconductor and member are copied and re-copyed FT4
The test piece was mounted on 820, and a running test was performed on 10000 sheets in an environment of 30 ° C. and 90%. Evaluation is 1st sheet, 100
The 0th image was evaluated.

Comparative Example 21 The same evaluation was made except that the sublimable antioxidant was removed from the member of Example 53. The images of Example 53 are the first and tenth images.
A good image was provided on both the 000th sheet, but in the case of Comparative Example 21, image deletion occurred at the 10,000th sheet.

Example 54 A charge generating layer coating liquid, a charge transporting layer coating liquid and a protective layer coating liquid having the following compositions were sequentially formed on a φ60 Al cylindrical support.
0.2 μm each charge generation layer after coating and drying, 19 μm
The charge transport layer and the protective layer having a thickness of 3 μm were formed to prepare the electrophotographic photosensitive member of the present invention. [Charge generating layer coating liquid] 4 parts of the charge generating substance having the following structural formula

[Chemical 48] Polyvinyl butyral (Sekisui Chemical Co., Ltd. S-REC BM-S) 2 parts Toluylene-2,4-diisocyanate 0.1 part Cyclohexanone 400 parts 2-Butanone 100 parts [Charge transport layer coating liquid] Charge transport of the following structural formula 9 parts of substance

[Chemical 49] Polycarbonate (Panlite K-1300, manufactured by Teijin Chemicals Ltd.) 11 parts Methylene chloride 80 parts [Protective layer coating liquid] Styrene-methyl methacrylate-3-hydroxypropyltrimethoxysilane copolymer 80 parts Tin oxide 90 parts Toluene 170 parts 2-butanone 100 parts Next, the structure of the members will be described. Compound No (X) -3 sublimable antioxidant 20 parts SBR 70 parts Paratoluenesulfonyl hydrazide 6 parts After mixing the above, the mixture was molded by pressure molding. The photoconductor and the member were mounted on a laser printer LP1060-sp3, and a running test of 7,000 sheets was performed under an environment of 15 ° C. and 30%. The evaluation was performed on the 7,000th image.

Comparative Example 22 The same evaluation was made except that the member of Example 54 was not mounted. The image of Example 54 gave a good image on the 7,000th sheet as well as the first sheet, but in the case of Comparative Example 22, the cleaning blade deteriorated and a chip was generated, and black streaks were generated in the image.

Example 55 An undercoat layer coating solution having the following composition was formed on the same support as in Example 53.
The charge generation layer coating liquid and the charge transport layer coating liquid are sequentially applied and dried to form an undercoat layer of 0.3 μm, a charge generation layer of 0.2 μm and a charge transport layer of 20 μm, respectively. An electrophotographic photoreceptor was created. [Undercoat layer coating liquid] 25% aqueous solution of water-soluble polyvinyl butyral (Sekisui Chemical Co., Ltd. S-REC W-201) 50 parts Water 150 parts Methanol 200 parts [Charge generating layer coating liquid] Charge of the following structural formula Generated material 5 parts

[Chemical 50] Polyester (Vylon 200 manufactured by Toyobo Co., Ltd.) 2 parts Toluylene-2,4-diisocyanate 0.1 part Tetrahydrofuran 200 parts 4-Methyl-2-pentanone 300 parts [Charge transport layer coating liquid] Charge transport of the following structural formula 8 parts of substance

[Chemical 51] Polycarbonate (Panlite L-1250 manufactured by Teijin Chemicals Ltd.) 10 parts Tetrahydrofuran 70 parts Next, the structure of the members will be described. Compound No (X) -7 sublimable antioxidant 40 parts Polyethylene 100 parts Foaming agent (FE-507, Eiwa Chemical Industry) 7 parts After mixing the above, the mixture was molded by extrusion molding. The photoconductor and the members were mounted on a copier Recopy FT4820. Thirty
A running test of 10,000 sheets was conducted at 90 ° C. and 90%. The evaluation was performed by I.D. D. Was measured with a commercially available Macbeth densitometer.

Comparative Example 23 Evaluations were made in the same manner except that the antioxidant was removed from the member of Example 55, and the following results were obtained.

[Table 22]

[0097]

By repeatedly using the photoreceptor of the present invention, it is possible to suppress a decrease in charging potential without impairing high sensitivity. That is, in the positive-positive development, it is possible to prevent the image density from decreasing, and in the negative-negative development, it is possible to prevent the background portion from being soiled. Further, since the photoreceptor of the present invention is excellent in environment resistance (reaction gas resistance) in a copying machine or the like,
It is highly durable and can prevent the occurrence of abnormal images.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a single-layer type electrophotographic photosensitive member which is an object of the present invention.

2A and 2B are schematic cross-sectional views of a laminated electrophotographic photosensitive member which is the object of the present invention.

FIG. 3 is a schematic cross-sectional view of an electrophotographic photosensitive member provided with an intermediate layer which is a target of the present invention.

4A and 4B are schematic cross-sectional views of an electrophotographic photosensitive member provided with a protective layer which is a target of the present invention.

[Table 8- (2)]

[Table 8- (3)]

[Table 8- (4)]

[Table 8- (5)] [Specific Examples of Compounds of General Formula (IX)]

[Table 9- (1)]

[Table 9- (2)]

[Table 10- (1)]

[Table 10- (2)]

The photoconductor to which the present invention is applied is not limited to a specific one, and various types can be applied. FIG. 1 shows the most basic photoreceptor, in which a photosensitive layer 12 is provided on a conductive substrate 11 (however, the photosensitive layer 12 here is a single layer), and FIG. ,
(B) is a photoconductor in which a photosensitive layer 12 including a charge generation layer 121 and a charge transport layer 122 is provided on a conductive substrate 11, and FIG. 3 is a conductive substrate of the photoconductor shown in FIG. 1 or 2. 1
1 and a type in which an intermediate layer 13 is provided between the photosensitive layer 12 and FIGS. 4 (A) and 4 (B) are provided on the photosensitive layer 12 of the photoreceptor shown in FIG. 1, FIG. 2 or FIG. This shows the type in which the protective layer 14 is provided.

The conductive substrate 11 has a volume resistance of 10 ¹³
Those exhibiting conductivity of Ωcm or less, such as aluminum,
Nickel, chromium, nichrome, copper, silver, gold, platinum, and other metals, tin oxide, indium oxide, and other metal oxides deposited or sputtered onto film or cylindrical plastic, paper, or aluminum , Aluminum alloy, nickel, stainless steel plates, etc. I. , I. It is possible to use a tube or the like which has been subjected to surface treatment by cutting, superfinishing, polishing or the like after being made into a liquid tube by a method such as I, extrusion or drawing.

When the photosensitive layer 12 is of an inorganic type, it may be Se-Te, amorphous Si, CdS, ZnO or the like.
Typical examples are chemical substances or alloys such as Se-Te-Cl and Se-As, and these are formed by a vapor deposition method or in a form dispersed in a binder resin. The binder resin is the same as the binder resin used as needed in the formation of the organic photosensitive layer described later. Further, the inorganic photosensitive layer may be formed by laminating photosensitive layers having different absorption wavelengths. On the other hand, if the photosensitive layer 12 is an organic type, it goes without saying that the photosensitive layer 12 may be a single layer.

First, the laminated type organic photosensitive layer (consisting of the charge generation layer 121 and the charge transport layer 122) will be described. The charge generation layer 121 is a layer containing a charge generation material as a main material, and if necessary, a binder. A resin may be used. As the binder resin, polyamide, polyurethane, polyester, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, poly-N-vinylcarbazole, polyacrylamide and the like are used.

As the charge generating substance, for example, CI Pigment Blue 25 [Color Index (CI) 2
1180], CI Pigment Red 41 (CI21
200), CI Acid Red 52 (CI4510
0), CI Basic Red 3 (CI4521)
0), phthalocyanine pigments having a porphyrin skeleton, azo pigments having a carbazole skeleton (described in JP-A-53-95033), and azo pigments having a distyrylbenzene skeleton (JP-A-53-133455). ), An azo pigment having a triphenylamine skeleton (described in JP-A-53-132547), and an azo pigment having a dibenzothiophene skeleton (JP-A-54-217).
28), azo pigments having an oxadiazole skeleton (described in JP-A-54-12742), and azo pigments having a fluorenone skeleton (JP-A-54-2283).
4), an azo pigment having a bisstilbene skeleton (described in JP-A-54-17733), and an azo pigment having a distyryloxadiazole skeleton (JP-A-54).
No. 2129), an azo pigment having a distyrylcarbazole skeleton (described in JP-A-54-17734), and CI Pigment Blue 16 (CI).
74100) and the like, phthalocyanine-based pigments, CI Eye Bat Brown 5 (CI73410), CI Bad Dye (CI73030) and other indigo pigments, Argos Scarlet B (manufactured by Violet), Indellens Scarlet R (manufactured by Bayer) and the like berylene. System pigments and the like. Among these charge generating substances, the azo pigment is preferable.

These charge generating substances may be used alone or in combination of two or more. The binder resin is appropriately used in an amount of 0 to 100 parts by weight, preferably 0 to 50 parts by weight, based on 100 parts by weight of the charge generating substance. The charge generation layer 121 is a ball mill, an attritor, a sand mill, or the like in which a charge generation substance is used together with a binder resin if necessary, using a solvent such as tetrahydrofuran, cyclohexane, dioxane, or dichloroethane,
It can be formed by appropriately diluting the dispersion and applying it. The coating can be performed by using a dip coating method, a spray coating method, a bead coating method, or the like. Charge generation layer 12
The film thickness of 1 is appropriately 0.01 to 5 μm, and preferably 0.1 to 2 μm.

The charge transporting layer 122 can be formed by dissolving or dispersing a charge transporting substance and a binder resin in a suitable solvent, coating the resultant on the charge generating layer 121, the conductive substrate 11 or the intermediate layer 13 and drying. .. If necessary, a plasticizer, a leveling agent, etc. may be added.
The charge transport material includes a hole transport material and an electron transport material.

As the hole-transporting substance, poly-N-vinylcarbazole and its derivative, poly-γ-carbazolylethylglutamate and its derivative, pyrene-formaldehyde condensate and its derivative, polyvinylpyrene, polyvinylphenanthrene and oxazole derivative. ,
Oxadiazole derivative, imidazole derivative, triphenylamine derivative, 9- (p-diethylaminostyryl) anthracene, 1,1-bis- (4-dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazoline, phenylhydrazones, Examples thereof include electron-donating substances such as α-phenylstilbene derivatives and benzidine derivatives.

Examples of the electron transport substance include chloranil, bromanyl, tetracyanoethylene, tetracyanoquinone dimethane, 2,4,7-trinitro-9-.
Fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2,4,5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,6
Examples thereof include electron-accepting substances such as 8-trinitro-4H-indeno [1,2-b] thiophen-4-one and 1,3,7-trinitrodibenzothiophene-5,5-dioxide. These charge transport materials may be used alone or in admixture of two or more.

As the binder resin, polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate , Polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate,
Cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinylcarbazole, acrylic resin,
Examples thereof include thermoplastic or thermosetting resins such as silicone resin, epoxy resin, melamine resin, urethane resin, phenol resin, and alkyd resin. As the solvent, tetrahydrofuran, dioxane, toluene, monochlorobenzene, dichloroethane, methylene chloride or the like is used. A suitable thickness of the charge transport layer 122 is about 5 to 50 μm.

Next, the case where the organic photosensitive layer 12 has a single layer structure (single-layer organic photosensitive layer) will be described. In this case as well, in most cases, a function-separated type of charge-generating substance and charge-transporting substance is used. That is, the compounds shown above can be used as the charge generating substance and the charge transporting substance.

The single-layer organic photosensitive layer can be formed by dissolving or dispersing the charge-generating substance, the charge-transporting substance and the binder resin in a suitable solvent, coating and drying the solution. Further, if necessary, a plasticizer, a leveling agent, etc. can be added. As the binder resin, the binder resins listed above for the charge transport layer 122 may be used as they are, or the binder resins listed for the charge generation layer 121 may be mixed and used.

The single-layer organic photosensitive layer is formed by dipping or spraying a coating solution in which a charge-generating substance, a charge-transporting substance and a binder resin are dispersed by a disperser using a solvent such as tetrahydrofuran, dioxane, dichloroethane, cyclohexanone. It can be formed by coating with a bead coat or the like.
The film thickness of the single-layer organic photosensitive layer is appropriately about 5 to 50 μm.

The electrophotographic photosensitive member is shown in FIGS.
As seen in (B), the conductive substrate 11 and the photosensitive layer 12
By providing the intermediate layer 13 between and, the effect as a photoconductor can be further improved, and the adhesiveness can also be improved.

The intermediate layer 13 is provided with an inorganic material such as Sio or Al ₂ O _{2 by} a method such as vapor deposition, sputtering or anodic oxidation, or a polyamide resin (JP-A-58-3075).
7, JP-A-58-98739 and the like),
Alcohol-soluble nylon resin (JP-A-60-1967)
66), a water-soluble polyvinyl butyral resin (described in JP-A-60-232553), a polyvinyl butyral resin (described in JP-A-58-106549), and a resin layer such as polyvinyl alcohol. You can This intermediate layer 13 has ZnO, TiO ₂ , Z
Pigment particles such as nS may be dispersed in an appropriate amount, and a silane coupling agent, a titanium coupling agent, a chromium coupling agent or the like may be used as the intermediate layer 13. The thickness of the intermediate layer 13 is preferably 0 to 5 μm.

In the above-mentioned photoreceptors, a protective layer 14 is provided on the photosensitive layer 12 if necessary (FIG. 4).
(A), (B)). As the resin used for the protective layer 14, ABS resin, ACS resin, olefin-vinyl copolymer resin, chlorinated polyether, allyl resin, phenol resin, polyacetal, polyamide, polyamideimide, polyarylate, polyallylsulfone, polybutylene. , Polybutylene terephthalate, polycarbonate,
Polyether sulfone, polyethylene, polyethylene phthalate, polyimide, methacrylic resin, polymethylpentene, polypropylene, polyphenylene oxide, polysulfone, polystyrene, AS resin, butadiene-styrene copolymer resin, polyurethane, polyvinyl chloride, polyvinylidene chloride, epoxy resin, etc. Is mentioned.

From the viewpoint of wear resistance, polytetrafluoroethylene resin, fluororesin, and silicone resin are added to the protective layer 14 as additives to reduce the friction coefficient and improve wear resistance and scratch resistance. In addition, abrasion resistance is improved even when an inorganic compound such as titanium oxide, an oxide, or potassium titanate is dispersed in the resin. Protective layer 14
Has a thickness of 0.5 to 10 μm, preferably 1 to 5 μm.

[0050]

The present invention will be described in more detail with reference to the following examples.

Comparative Example 1 A coating film for an undercoat layer, a coating solution for a charge generation layer, and a coating solution for a charge transport layer were sequentially coated and dried on an Al vapor-deposited polyester film to give a thickness of 0. An undercoat layer having a thickness of 2 μm, a charge generation layer having a thickness of 0.3 μm, and a charge transporting layer having a thickness of 22 μm were formed to prepare a photoconductor of a comparative example. [Undercoat layer coating liquid] Methanol 80 parts n-Butanol 20 parts Alcohol-soluble nylon (Alamine CM-8000, manufactured by Toray) 3 parts Alcohol-soluble nylon is dissolved in a methanol / n-butanol mixed solvent having the above composition, and the undercoat is applied. A layer coating solution was prepared. [Charge generation layer coating liquid] Azo pigment with the following structure

[Chemical 10] Cyclohexane 100 parts Tetrahydrofuran 50 parts [Charge transport layer coating liquid] Dichloromethane 83 parts Polycarbonate (Panlite K-1300, manufactured by Teijin Kasei) 10 parts Charge transport material (formula 11) 7 parts

[Chemical 11] The above photoconductor was grounded to a conductive layer and joined by a belt to obtain a photoconductor for mounting.

Examples 1 to 9 The antioxidants shown in Table 11 were directly deposited on the photoconductor of Comparative Example 1 to obtain electrophotographic photoconductors of the present invention. Example 1
9 to 9 and each of the photoconductors of Comparative Example 1 were attached to a cassette for LP-4080, and left in a nitrogen dioxide exposure tester under conditions of NO ₂ concentration of 5 ppm, 25 ° C., and humidity of 35% for 5 days. After that, Ricoh laser printer LP-40
Printing was performed at 80, the image density of the image area was measured with a Macbeth densitometer, and the values on the first and 1000th sheets are shown in Table 11.

[Table 11]

Comparative Example 2 A film was formed on an aluminum cylinder having a diameter of 40 mm by plasma CVD. A 5 μm amorphous silicon (a-Si: H) layer was provided as a charge generation layer. Next, a charge transport layer coating liquid having the following composition was applied onto this and dried to form a charge transport layer having a thickness of 20 μm, thereby preparing an electrophotographic photoreceptor of Comparative Example. [Charge transport layer coating liquid] Toluene 320 parts Polycarbonate resin (Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.) 10 parts Charge transport material (Chemical formula 12) 49 parts

[Chemical 12]

Examples 10 to 18 The photoreceptor of Comparative Example 2 was uniformly charged by a corona charger having a discharge pressure of -5.3 kV, and immediately the antioxidant of Table 12 was placed in the dark. By adhering to the surface, an electrophotographic photoreceptor of the present invention was prepared. Each of the photoconductors of Examples 10 to 18 and Comparative Example 2 was attached to a cassette for LP-1060, and left in an ozone exposure tester at an ozone concentration of 5 ppm at 35 ° C for 5 days. After that, Ricoh laser printer LP-
Printing was carried out at 1060 and SP-3, and the stain on the background portion of the image was visually evaluated in 5 grades. However, rank 5
Is good, and rank 1 is bad. The results are shown in Table 12.

[Table 12]

Comparative Example 3 An aluminum cylinder having a diameter of 60 mm was sequentially coated with a coating solution for charge transport layer, a coating solution for charge generating layer, and a coating solution for protective layer having the following compositions and dried to have a thickness of 17 μm each. Charge transport layer,
A 0.5 μm thick charge generating layer and a 2 μm thick protective layer were formed to prepare an electrophotographic photosensitive member of Comparative Example 3. [Charge transport layer coating liquid] Chloroform 9 parts Polyester (Vylon 200, manufactured by Toyobo) 1 part Charge transport material (Chemical formula 13) 1 part Dissolve polyester and charge transport material in chloroform,
A charge transport layer coating liquid was prepared.

[Chemical 13] [Coating liquid for charge generation layer] 6 parts of azo pigment having the following structure

[Chemical 14] Polyvinyl butyral (Sekisui Chemical Co., Ltd. S-REC BL-1) 1 part Cyclohexane 200 parts 2-butane 50 parts [Coating liquid for protective layer] Styrene-methyl methacrylate-2-hydroxyethyl methacrylate-trifluoroethyl methacrylate copolymer 10 parts Conductive titanium oxide 8 parts Toluene 100 parts n-Butanol 50 parts

Examples 19 to 27 The antioxidants shown in Table 13 which were microencapsulated with polymethylmethacrylate were attached to the photoreceptor of Comparative Example 3 to obtain electrophotographic photoreceptors of the present invention. .. Example 19
.About.27 and the photoconductors of Comparative Example 3 were covered with black paper for light shielding, housed in a cardboard box, and allowed to stand in an environment of 30.degree. C. and 90% for one month. Next, each photoconductor is attached to JP-A-60-10.
Using the measuring device disclosed in Japanese Patent No. 0167, the following evaluation was made. Corona charging was performed for 20 seconds at a discharge voltage of +5.7 kV, followed by dark decay for 20 seconds, and then irradiation with 10 lux of tungsten light. At this time, the surface potential V ₁ (V), V after 1 second and 20 seconds after the start of charging
The surface potential V ₄₀ (V) after ₂₀ (V) and dark decay 20 seconds is measured, and the exposure amount E1 / 2 (lux · sec) required to optically attenuate V ₄₀ to half the potential is measured. did. The dark decay rate (DD) is defined by the following equation. D. D = V ₄₀ / V ₂₀ Further, charging and exposure under the above conditions were performed for 30 minutes at the same time to fatigue, and then the same measurement as above was performed again. The test results are shown in Table 13, and all measurements were performed at room temperature and normal humidity.

[Table 13]

Comparative Example 4 An AS-Se photosensitive layer having a thickness of 60 μm was provided on an aluminum cylinder having a diameter of 80 mm by a vacuum deposition method. A protective layer coating solution having the following composition was applied onto this and dried to form a protective layer having a thickness of 3 μm to prepare a photoconductor of Comparative Example 4. [Protective layer coating liquid] Styrene-methacrylic acid-N methylolmethacrylamide resin 10 parts Tin oxide containing 10% antimony oxide 30 parts Toluene 80 parts n-Butanol 70 parts

Examples 28 to 36 The photoconductor of Comparative Example 4 was immersed in an acetone solution containing 3% by weight of each antioxidant shown in Table 14 and then pulled up and dried to obtain an electrophotographic photoconductor of the present invention. .. Examples 28-3
No. 6 and Comparative Example 4 were replaced with Recopy FT-6550.
Immediately after being placed in an environment of 30 ° C. and 90%, it was left for 2 weeks. After that, copying was performed under the same environment, and the image deletion phenomenon occurring in the image was visually evaluated in five levels. However, the rank 5 means that the image deletion does not occur, and the rank 1 means that the image deletion remarkably occurs. The results are shown in Table 14.

[Table 14]

Claims (5)

[Claims] 1. An electrophotographic photoreceptor comprising an antioxidant attached to the surface of the photoreceptor. 2. The electrophotographic photosensitive member according to claim 1, wherein a member containing a sublimable antioxidant is used as a means for attaching an antioxidant to the surface of the photosensitive member. 3. A method for preventing characteristic deterioration of an electrophotographic photosensitive member, which comprises treating the surface of the electrophotographic photosensitive member installed in a copying machine with a member containing an antioxidant. 4. The method for preventing deterioration of characteristics of an electrophotographic photosensitive member according to claim 2, wherein the member containing an antioxidant is a sheet-shaped member. 5. The method for preventing deterioration of characteristics of an electrophotographic photosensitive member according to claim 2, wherein the member containing an antioxidant is a cleaning member.