JP2011128436A - Monolayer electrophotographic photoreceptor and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a monolayer electrophotographic photoreceptor which is excellent in adhesion strength of its organic photosensitive layer and its conductive substrate to each other, and also is excellent in electric characteristics and in image characteristics, and to provide a method for manufacturing the same. <P>SOLUTION: The monolayer electrophotographic photoreceptor includes: a cylindrical conductive substrate which is composed of aluminum or an aluminum alloy and of which the surface has an ionization potential (Ip) of 4.2-5.0 eV; and an organic photosensitive layer which is formed on the surface of the cylindrical conductive substrate, and which includes a polycarbonate resin as a binder resin. The cylindrical conductive substrate is formed by surface treatment comprising immersion in hot pure water under a condition of a range 1 shown in Figure 4. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a single-layer electrophotographic photosensitive member applied to an electrophotographic apparatus such as a printer or a copying machine, to which electrophotographic technology is applied.

  2. Description of the Related Art As electrophotographic apparatuses such as laser printers, fax machines, and digital multi-function machines applying electrophotographic technology, those equipped with an organic photoreceptor are widely used. This is because the organic photoconductor has advantages in terms of cost and easy disposal as compared with an inorganic photoconductor mainly made of silicon or selenium.

  Organic photoconductors (hereinafter also referred to as “photoconductors”) are further broadly divided into negative charge types and positive charge types. The negative charge type generally has a function separation type structure (hereinafter referred to as “lamination type”) in which functions are separated into a plurality of layers, and the positive charge type is a single layer in which all functions are provided in a single layer. Mold structure is mainstream.

  An organic photoreceptor is manufactured by immersing a cylindrical conductive substrate in a solution obtained by dissolving or dispersing an organic material in an organic solvent, pulling it up and drying it to form an organic photosensitive layer. Aluminum or the like is used as a material for the cylindrical conductive substrate.

  The photoconductor is rotatably mounted inside the electrophotographic apparatus and is subjected to various mechanical stresses. For this reason, the adhesion at the interface between the substrate surface and the organic photosensitive layer becomes a problem, and the organic photosensitive layer is required to have a strength capable of withstanding the stress during the service life.

  The mechanical stress is received from various members that come into contact with the photoreceptor in a process executed when an image is formed in the electrophotographic apparatus. Examples of the member include a charging roller, a developing roller, toner, a transfer roller, paper, and a cleaning blade.

There are two meanings of the strength of the photoconductor against mechanical stress.
One is the strength of the organic photosensitive layer itself. The organic photosensitive layer is required not to be deformed or broken against the stress from the process member. Deformation or destruction appears in an image and becomes a serious problem in terms of photoreceptor quality.

  The other is the adhesion strength of each layer in the layer structure including the substrate and the photosensitive layer. Since the photosensitive member is intermittently subjected to the above-described mechanical stress during the rotation operation in the electrophotographic apparatus, the photosensitive layer is peeled off at the layer interface when the adhesion strength is weak. If even a part of the layer is peeled off, the photosensitive member cannot form an image at that part, which becomes a serious quality problem. Further, even if it does not reach the peeling of the layer, if it is in a state conforming to it, the electrical characteristics are deteriorated, and the image quality cannot be maintained. In order to maintain stable electrical characteristics, the photoreceptor needs to be firmly in contact with each other so that negative charges (electrons) or positive charges (holes) can move across each layer and each interface.

  As described above, the layer structure of the organic photoreceptor includes a laminated type and a single layer type. In the case of the laminated type, the lower layer undercoat layer that forms an interface with the substrate has a function of improving adhesion. Yes. Specifically, the binder resin for the undercoat layer is made of a nylon resin or a thermosetting resin as a countermeasure.

  On the other hand, in the case of a single layer type, a single layer basically has all the functions, so that the binder resin constituting the layer is adhesive, electrical characteristics, image characteristics, charge generation material dispersibility, mechanical It is required to satisfy a plurality of evaluation items such as wear resistance, filming resistance and productivity.

The polycarbonate resin generally used for this purpose is a very excellent material in terms of dispersibility of the charge generating material, mechanical wear and filming resistance, but has a problem in adhesion strength.
Patent Document 1 (see claims, paragraph 0088) shows that the adhesion strength is improved by adding a polyester resin to a polycarbonate binder. However, in this case, problems may arise in terms of dispersibility of the charge generating material, mechanical wear, and filming resistance.

  Patent Document 2 shows that the adhesion strength is improved by providing an intermediate layer between the support and the photosensitive layer. However, even in this case, problems may occur in terms of electrical characteristics, image characteristics, and cost.

  As described above, the photoreceptors disclosed in Patent Documents 1 and 2 have not obtained satisfactory results in terms of characteristics other than adhesion strength or cost, and are excellent in characteristics including adhesion strength more easily. What is needed is a method of providing a single layer electrophotographic photoreceptor.

  In Patent Document 3, the outer surface of a cylindrical substrate made of aluminum or an aluminum alloy is degreased and cleaned, and subsequently immersed in a warm pure water bath having a temperature of 60 ° C. to 90 ° C. and a specific resistance of 1 MΩ or more to hydrate and oxidize. A method for producing an organic photoconductor for electrophotography, in which a film is formed and further subjected to a heat treatment at a temperature of 100 ° C. to 150 ° C. for 5 to 30 minutes, and then a photosensitive layer containing an organic photoconductive material is formed on the surface. (See claims, paragraphs 0014-0020). However, this document does not discuss the adhesion strength between an organic photosensitive layer containing a polycarbonate resin as a binder resin and a conductive substrate.

Japanese Patent No. 3262998 Japanese Patent No. 3791227 Japanese Patent Laid-Open No. 7-295241

  Accordingly, an object of the present invention is to provide a single-layer electrophotographic photoreceptor having an organic photosensitive layer on the surface of a cylindrical conductive substrate made of aluminum or an aluminum alloy, and having excellent mechanical stress. There is. Further, the object of the present invention is to provide both an excellent mechanical strength of the organic photosensitive layer and an adhesive strength between the organic photosensitive layer and the conductive substrate, without setting an intermediate layer or an alumite layer, and adding an additive. An object of the present invention is to provide a single-layer electrophotographic photoreceptor excellent in characteristics and image characteristics and a method for producing the same.

  In order to solve the above problems, the single-layer electrophotographic photosensitive member according to claim 1 is made of aluminum or an aluminum alloy, and has an ionization potential (hereinafter also referred to as “Ip”) on the surface thereof of 4.2 to 5. It is characterized by comprising a cylindrical conductive substrate of 0 eV and an organic photosensitive layer formed on the surface of the cylindrical conductive substrate and containing a polycarbonate resin as a binder resin.

  Therefore, an organic photosensitive layer containing a polycarbonate resin as a binder resin is made of aluminum or an aluminum alloy, and is formed in close contact with the surface of a cylindrical conductive substrate having an Ip of 4.2 eV or more and 5.0 eV or less. Has been.

Furthermore, the single-layer electrophotographic photosensitive member according to claim 2 is characterized in that the ionization potential is 4.5 to 5.0 eV in claim 1.
The single-layer electrophotographic photosensitive member according to claim 3 is immersed in warm pure water under the conditions of temperature and time within the range 1 shown in FIG. And surface-treated.

Therefore, the cylindrical conductive substrate is subjected to a surface treatment under the condition of range 1 in FIG. 4 so that the surface Ip is 4.2 eV or more and 5.0 eV or less.
Furthermore, the single-layer electrophotographic photosensitive member according to claim 4 is immersed in warm pure water under the conditions of temperature and time within the range 2 shown in FIG. And surface-treated.

Therefore, the cylindrical conductive substrate is subjected to a surface treatment under the condition of range 2 in FIG. 4 so that the surface Ip is 4.5 eV or more and 5.0 eV or less.
The method for producing a single-layer type electrophotographic photosensitive member according to claim 7 includes the temperature and time conditions included in the range 1 shown in FIG. 4 on the entire surface of the cylindrical conductive substrate made of aluminum or an aluminum alloy. And dipping in warm pure water and forming an organic photosensitive layer containing a polycarbonate resin as a binder resin on the surface of the cylindrical conductive substrate.

  Therefore, all surfaces of the cylindrical conductive substrate made of aluminum or an aluminum alloy are treated by the step of immersing under the condition of range 1 in FIG. 4, and the organic photosensitive layer containing the polycarbonate resin adheres to this surface. It is formed.

  Further, in the method for producing a single-layer electrophotographic photosensitive member according to claim 8, all the surfaces of the cylindrical conductive substrate made of aluminum or aluminum alloy are subjected to temperature and time conditions included in the range 2 shown in FIG. And a step of forming an organic photosensitive layer containing a polycarbonate resin as a binder resin on the surface of the cylindrical conductive substrate.

  Therefore, the entire surface of the cylindrical conductive substrate made of aluminum or aluminum alloy is treated by the step of immersing under the condition of range 2 in FIG. 4, and the organic photosensitive layer containing the polycarbonate resin adheres to this surface. It is formed.

  According to the present invention, a cylindrical conductive substrate made of aluminum or an aluminum alloy and having a surface Ip of 4.2 to 5.0 eV is combined with an organic photosensitive layer containing a polycarbonate resin as a binder resin. Thus, it is possible to provide a single layer type electrophotographic photoreceptor excellent in all of adhesion strength, electrical characteristics, and image characteristics. Furthermore, by setting Ip to 4.5 to 5.0 eV, the adhesion strength can be improved while maintaining excellent electrical characteristics and image characteristics.

  In addition, according to the present invention, the step of immersing all surfaces of the cylindrical conductive substrate made of aluminum or aluminum alloy under the condition of range 1 in FIG. 0.0 eV, and by adding a step of forming an organic photosensitive layer containing a polycarbonate resin as a binder resin on the surface, the adhesion strength, electrical characteristics, and image can be simplified without increasing costs and reducing productivity. It is possible to provide a method for producing a single layer type electrophotographic photoreceptor excellent in all characteristics.

  Further, by the step of setting the condition in range 2 in FIG. 4, the surface of the cylindrical conductive substrate has an Ip of 4.5 to 5.0 eV, and a method for producing a single-layer electrophotographic photosensitive member with further excellent adhesion strength is provided. it can.

1 is a schematic cross-sectional view of an essential part showing a single-layer electrophotographic photosensitive member according to a first embodiment of the present invention. It is a flowchart showing the manufacturing method of the single layer type electrophotographic photoconductor which concerns on the 1st Embodiment of this invention. It is a principal part cross-sectional schematic diagram which shows the single layer type electrophotographic photoreceptor which concerns on the 2nd Embodiment of this invention. It is a graph which shows the conditions which process a cylindrical conductive base | substrate using warm pure water.

Embodiments of the present invention will be described below with reference to the drawings. In addition, in the following drawings, the same code | symbol was attached | subjected to the member which has the same function.
(First embodiment)
FIG. 1 is a schematic cross-sectional view of an essential part showing a single layer type electrophotographic photosensitive member according to the first embodiment, and FIG. 2 is a production of the single layer type electrophotographic photosensitive member according to the first embodiment. 3 is a flowchart showing a method.

  The single-layer electrophotographic photoreceptor 1 of the present invention includes an organic photosensitive layer 20 that is directly formed on the surface of a cylindrical conductive substrate 10. The organic photosensitive layer 20 is a single layer type composed of one layer having both a charge generation function and a charge transport function.

  The cylindrical conductive substrate 10 serves as a support for each of the other layers as well as serving as an electrode for the photoreceptor. The material is preferably aluminum or an aluminum alloy, and particularly preferably A6000 series aluminum alloy A6063 (JIS H 4040: 1999). The ionization potential (Ip) on the surface of the cylindrical conductive substrate 10 is 4.2 to 5.0 eV, preferably 4.5 to 5.0 eV.

  The shape of the conductive substrate may be any of a plate shape and a film shape as well as a cylindrical shape. Further, it is desirable that the surface of the cylindrical conductive substrate 10 is processed by cutting or polishing.

The organic photosensitive layer 20 includes a binder resin, a charge generation material, a hole transport material, and an electron transport material as main components, and further includes additives as necessary.
The binder resin is a polycarbonate resin having a weight average molecular weight of 10,000 to 100,000, more preferably 20,000 to 50,000, bisphenol A type, bisphenol Z type, bisphenol A type-biphenyl copolymer, bisphenol Z type-biphenyl. Examples thereof include polycarbonate resins such as copolymers, bisphenol ZC type, and bisphenol C type. Two or more different types of polycarbonate resins may be mixed and used, or the same type of resins having different molecular weights may be mixed and used. The content of the binder resin is 40% by weight to 60% by weight with respect to the solid content of the organic photosensitive layer 20.

  As the charge generation material, a phthalocyanine pigment can be used. As the phthalocyanine pigment, metal-free phthalocyanine, copper phthalocyanine, and titanyl phthalocyanine are suitable. The content of the charge generating material is 0.7 wt% to 2 wt% with respect to the solid content of the organic photosensitive layer 20.

  Such phthalocyanines have various crystal forms such as X-type metal-free phthalocyanine, τ-type metal-free phthalocyanine, ε-type copper phthalocyanine, α-type titanyl phthalocyanine, β-type titanyl phthalocyanine, Y-type titanyl phthalocyanine, amorphous titanyl phthalocyanine, In the CuKα: X-ray diffraction spectrum described in JP-A-8-209023, titanyl phthalocyanine having a maximum peak at a Bragg angle 2θ of 9.6 ° is known. Among these, for example, X-type metal-free phthalocyanine, α-type titanyl phthalocyanine, Y-type titanyl phthalocyanine described in JP-A No. 2001-228637, and titanyl according to the invention described in JP-A-2001-330972 More preferred is phthalocyanine.

  As the hole transport material, styryl compounds, hydrazone compounds, pyrazoline compounds, pyrazolone compounds, oxadiazole compounds, oxazole compounds, arylamine compounds, benzidine compounds, stilbene compounds, polyvinylcarbazole, polysilanes, and the like can be used. The hole transport materials can be used alone or in combination of two or more. A styryl compound is particularly preferable. The content of the hole transport material is 20 wt% to 40 wt% with respect to the solid content of the organic photosensitive layer 20.

  As an electron transport material, succinic anhydride, maleic anhydride, dibromosuccinic anhydride, phthalic anhydride, 3-nitrophthalic anhydride, 4-nitrophthalic anhydride, pyromellitic anhydride, pyromellitic acid, trimellitic acid, Trimellitic anhydride, phthalimide, 4-nitrophthalimide, tetracyanoethylene, tetracyanoquinodimethane, chloranil, bromanyl, o-nitrobenzoic acid, trinitrofluorenone, quinone, benzoquinone, diphenoquinone, naphthoquinone, anthraquinone, stilbenequinone, azoquinone An electron accepting material such as an electron transporting material can be used. These electron accepting substances and electron transporting substances can be used alone or in combination of two or more. The content of the electron transport material is 10% by weight to 25% by weight with respect to the solid content of the organic photosensitive layer 20.

  The organic photosensitive layer 20 may contain a deterioration inhibitor such as an antioxidant or a light stabilizer for the purpose of improving environmental resistance and stability against harmful light. Compounds used for such purposes include chromanol derivatives such as tocopherol and esterified compounds, polyarylalkane compounds, hydroquinone derivatives, etherified compounds, dietherified compounds, benzophenone derivatives, benzotriazole derivatives, thioether compounds, phenylenediamine derivatives. Phosphonic acid ester, phosphorous acid ester, phenol compound, hindered phenol compound, linear amine compound, cyclic amine compound, hindered amine compound and the like.

  Further, the organic photosensitive layer 20 may contain a leveling agent such as silicone oil or fluorine-based oil for the purpose of improving the leveling property of the formed film and imparting lubricity.

  Further, in the organic photosensitive layer 20, for the purpose of reducing the friction coefficient and imparting lubricity, metals such as silicon oxide (silica), titanium oxide, zinc oxide, calcium oxide, aluminum oxide (alumina), zirconium oxide and the like. Oxides, sulfates such as barium sulfate and calcium sulfate, metal nitride fine particles such as silicon nitride and aluminum nitride, fluorine resin particles such as tetrafluoroethylene resin and silicone resin fine particles, fluorine comb-type graft A polymer containing fluorine, such as a polymerized resin, or a polymer containing silicon may be contained.

In order to maintain a practically effective surface potential, the thickness of the organic photosensitive layer 20 is preferably in the range of 3 to 100 μm, more preferably 10 to 50 μm.
Next, a method for producing the single layer type electrophotographic photosensitive member of the present invention will be described.

  As shown in FIG. 2, the method for producing a single-layer type electrophotographic photosensitive member of the present invention includes a step (S1) of treating the surface of a conductive substrate using warm pure water, that is, a cylindrical conductive material made of aluminum or an aluminum alloy. The step of immersing the substrate 10 in warm pure water at 65 to 75 ° C. and the step of forming an organic photosensitive layer on the surface of the conductive substrate (S2), that is, the organic photosensitive layer 20 containing a polycarbonate resin as a binder resin is the cylindrical shape. And a step of forming the surface of the conductive substrate 10 at least in this order.

  In the step (S1) of treating the surface of the conductive substrate, the cylindrical conductive substrate 10 made of aluminum or an aluminum alloy is treated so that the Ip of the surface thereof is 4.2 to 5.0 eV. Immerse in warm pure water under the conditions of the temperature and immersion time shown in. More preferably, it is the conditions of temperature and immersion time shown in the range 2 of FIG. 4, and the ionization potential is 4.5 to 5.0 eV at this time. The ionization potential is measured by photoelectron spectroscopy.

  In FIG. 4, the condition indicated by the range 1 is (T, Dt) = (65, 35), (65, 35) when the temperature T (° C.) of hot pure water is taken on the horizontal axis and the immersion time Dt (seconds) is taken on the vertical axis. 110), (75, 15), and (75, 90) are temperatures and immersion times included in the inner region of the parallelogram having vertices, and are further expressed by the following equations (i) to (iii): The area to be filled is filled.

  In addition, the condition indicated by range 2 in the figure is the inside of a parallelogram having apexes at (T, Dt) = (65, 50), (65, 110), (75, 30), (75, 90). The temperature and the dipping time included in the region of the above, and further satisfy the region represented by the following formulas (iv) to (vi).

  By such warm pure water treatment, the ionization potential on the surface of the cylindrical conductive substrate 10 is controlled within a desired numerical range, and a photoconductor excellent in adhesion strength, electrical characteristics, and image characteristics can be produced.

  In this step (S1), the following process may be further performed. The surface of the cylindrical conductive substrate 10 may be washed with an alkaline detergent or the like before the hot pure water treatment. In addition, after the warm pure water treatment, the cylindrical conductive substrate 10 may be once cooled, and then heat treated under conditions of a temperature of 50 to 80 ° C. and a time of 5 to 30 minutes for the purpose of removing moisture remaining on the substrate.

The hydrated oxide film formed on the surface by the hot pure water treatment is bayerite (Al ₂ O ₃ .3H ₂ O), and boehmite (Al ₂ O, which is a more stable film when subjected to high-temperature heat treatment at about 90 ° C. or higher. It is known to change to ₃ · H ₂ O). From the viewpoint of improving the adhesion strength with the photosensitive layer, since the surface of the substrate is not positively stabilized, heat treatment is performed at a temperature at which boehmite formation is not promoted.

  In the step (S2) of forming the organic photosensitive layer, the above-mentioned constituent materials including polycarbonate resin are dissolved and dispersed together with an appropriate solvent to prepare a coating solution, which is applied onto the cylindrical conductive substrate 10 by a known coating method. And drying to remove the solvent.

  Examples of such solvents include alcohols such as methanol, ethanol, n-propanol, i-propanol, n-butanol and benzyl alcohol, ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone and cyclohexanone, dimethylformamide (DMF). ), Amides such as dimethylacetamide, sulfoxides such as dimethyl sulfoxide, cyclic or linear ethers such as tetrahydrofuran (THF), dioxane, disoxolane, diethyl ether, methyl cellosolve, ethyl cellosolve, methyl acetate, ethyl acetate, Esters such as n-butyl acetate, aliphatic halogenated hydrocarbons such as methylene chloride, chloroform, carbon tetrachloride, dichloroethylene and trichloroethylene, mineral oil such as ligroin, Zen, toluene, aromatic hydrocarbons such as xylene, chlorobenzene, aromatic halogenated hydrocarbons such as dichlorobenzene and the like are used, may be mixed two or more of these.

  As a method for dispersing and dissolving the coating liquid, a known method such as a paint shaker (paint conditioner), a bead mill (sand grinder) such as a ball mill or a dyno mill, or ultrasonic dispersion can be used. Known methods such as dip coating, ring coating (seal coating), spray coating, bar coating, and blade coating can be used.

  The drying temperature and drying time in the drying can be set in view of the type of solvent used, production cost, etc., but preferably the drying temperature is from room temperature to 200 ° C., and the drying time is from 10 minutes to 2 hours. Set within the range. More preferably, the drying temperature is within the range of the boiling point of the solvent to the boiling point + 80 ° C. In addition, this drying is usually performed under normal pressure or reduced pressure, while still or under ventilation.

In this way, the single layer type electrophotographic photosensitive member of the present invention is manufactured.
The single-layer electrophotographic photosensitive member of the present invention can be used in a known electrophotographic process. In other words, it can be suitably used in general electrophotographic processes having processes such as charging, exposure, development, transfer, and fixing, and can be used in copying machines, printers, fax machines, and the like having these electrophotographic processes. .

  As the charging process, there are a positive charging process for charging the photoreceptor to the positive electrode and a negative charging process for charging the negative electrode. The photoreceptor of the present invention can be used in a negative charging process, but it is preferably used in a positive charging process because it exhibits particularly high sensitivity in a positive charging process.

  As a charger in the charging process, there are a non-contact charger using a corotron and a scorotron, and a charger that performs charging by contacting (or approaching) a photosensitive member in a roller shape or a brush shape. The photoreceptor of the present invention can be used in a process using either charger.

  As a light source used in the exposure process, a light source having a wavelength range in which the photoconductor is sensitive is usually used, and white light such as a halogen lamp and a fluorescent lamp, laser light, LED (Light Emitting Diode) light, and the like are preferable. It is. In particular, when phthalocyanine is used as the charge generating material, a semiconductor laser light or LED light having a wavelength in the vicinity of 600 to 800 nm is more preferable. In addition, when a compound having absorption at 450 nm or less is used as the charge generating material, it is possible to use semiconductor laser light or LED light having a wavelength of 450 nm or less.

  The development process mainly includes a dry development system using dry toner and a liquid development (wet development) system using liquid toner, and the photoreceptor of the present invention can be used in both systems. In the case of the liquid development method, it is desirable to adopt a known method so that the components of the photoreceptor do not dissolve in the solvent contained in the liquid toner.

  In addition, the development process includes a reversal development method in which toner is developed in an exposed portion and a normal development method in which toner is developed in a non-exposed portion. In particular, when phthalocyanine is used as a charge generation material, the reversal is developed. It is preferably used in a development process.

  Known electrophotographic processes include those having a cleaning process after the transfer process for the purpose of removing or scattering the untransferred toner remaining on the photoreceptor, and those having no cleaner. . The photoreceptor of the present invention can be used in both processes.

Further, the known electrophotographic process has a charge removal process by exposure after the transfer process for the purpose of removing charges remaining on the photoreceptor or averaging the surface potential, and does not have this. Things exist. The photoreceptor of the present invention can be used in both processes.
(Second Embodiment)
FIG. 3 is a schematic cross-sectional view of the relevant part showing a single-layer electrophotographic photosensitive member according to the second embodiment. The single-layer electrophotographic photosensitive member according to the second embodiment is a modification of the first embodiment and has many common parts. Therefore, description of common parts will be omitted and different parts will be described below. . In addition, the same code | symbol is attached | subjected to the same element as the element demonstrated in 1st Embodiment.

The single-layer electrophotographic photoreceptor 1 according to the second embodiment is obtained by forming a protective layer 30 on the surface of the organic photosensitive layer 20.
The protective layer 30 can be provided for the purpose of improving printing durability, and is formed by a layer mainly composed of a binder resin or a vapor phase growth method such as amorphous carbon or amorphous silicon-carbon. It consists of an inorganic thin film, a coating film formed by vapor deposition of silica or alumina, and the like.

  As the binder resin, those used for the organic photosensitive layer 20 or a three-dimensional cross-linked resin such as a siloxane resin can be used. In the binder resin, silicon oxide (silica), titanium oxide, zinc oxide, calcium oxide, aluminum oxide (alumina), for the purpose of improving conductivity, reducing the friction coefficient, and imparting lubricity, etc. Metal oxides such as zirconium oxide, sulfates such as barium sulfate and calcium sulfate, metal nitride fine particles such as silicon nitride and aluminum nitride, fluorine resin particles such as tetrafluoroethylene resin and silicone resin fine particles, A polymer containing fluorine such as a fluorine-based comb-type graft polymerization resin or a polymer having a network structure containing silicon may be contained.

  In addition, for the purpose of imparting charge transportability, a silicone oil is included for the purpose of improving the leveling property of the formed film and imparting lubricity to the hole transport material and electron transport material used in the organic photosensitive layer 20. Or a leveling agent such as fluorine-based oil.

  The film thickness of the protective layer 30 is preferably in the range of 0.1 to 50 μm, more preferably 1 to 10 μm, as long as the function of the organic photosensitive layer 20 is not impaired. Further, a plurality of protective layers may be laminated.

After the step (S2) for forming the organic photosensitive layer 20, the protective layer 30 is prepared by dissolving and dispersing the constituent materials together with an appropriate solvent to prepare a coating solution, and a cylindrical conductive substrate by a known coating method. It is formed by applying onto 10 and drying to remove the solvent.
(Example 1)
EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to these Examples.

  As the cylindrical conductive substrate 10, an aluminum base tube (material: A6063) having a φ30 mm length and a cutting process on the surface is prepared, and this is washed with an alkaline detergent (Castrol 450: Castrol Co., Ltd., concentration 2%, room temperature). After using and washing, it was immersed in warm pure water at 65 ° C. and pulled up from the warm pure water bath at a speed of 10 mm / second. At this time, the cylindrical conductive substrate 10 is plunged so that its length direction is substantially perpendicular to the surface of the warm pure water, and is pulled up, so that the immersion time in warm pure water at each position from the lowermost end to the uppermost end is increased. Different. As Example 1-1, a band-like region in which the immersion time was 35 seconds was specified, and evaluation of Ip, adhesion strength, electrical characteristics, image characteristics, and filming resistance described later was performed. Similarly, in Examples 1-2, 1-3, and 1-4, the band-like regions in which the immersion times are 50 seconds, 70 seconds, and 110 seconds are evaluated.

  Thereafter, the aluminum tube was cooled to room temperature and then treated at 60 ° C. for 30 minutes in a heating furnace. The purpose of this heat treatment is to remove water droplets remaining on the substrate surface by the hot pure water treatment.

  Next, the following materials were prepared, and a photosensitive layer coating solution was prepared by dissolving a polycarbonate resin as a binder resin in a solvent and further dispersing a charge generating material, a hole transporting material and an electron transporting material. In addition, the density | concentration described after the material name shows the ratio with respect to a coating liquid.

Solvent: 75% by weight of tetrahydrofuran
Binder resin: Bisphenol Z-type polycarbonate resin having a repeating unit of the following formula (1) (molecular weight 50,000: Mitsubishi Gas Chemical Co., Ltd. Iupizeta PCZ-500) 11.5% by weight
Charge generation material: X-type metal-free phthalocyanine 0.5% by weight
Hole transport material: 9% by weight of a styryl compound represented by the following formula (2)
Electron transport material: 4% by weight of an azoquinone compound represented by the following formula (3)

This coating solution was applied to the surface of the above-mentioned aluminum base tube in the form of a film by a dipping method, heated and dried at 100 ° C. for 60 minutes to remove the solvent, and the organic photosensitive layer 20 having a thickness of 30 μm was obtained.
The single-layer type electrophotographic photosensitive member 1 of Examples 1-1, 1-2, 1-3, and 1-4 was manufactured through the above steps.
[Comparative Example 1]
The single layer type of Comparative Examples 1-5 and 1-6 except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds. An electrophotographic photosensitive member was produced.
(Example 2)
Examples 2-1 and 2 were carried out in the same manner as in Example 1 except that the temperature of hot pure water was set to 70 ° C. and the pulling rate was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds. -2, 2-3, 2-4 single layer type electrophotographic photosensitive member 1 was produced.
[Comparative Example 2]
Single layers of Comparative Examples 2-5 and 2-6 except that the temperature of warm pure water was set to 70 ° C. and the pulling rate was adjusted so that the immersion time conditions were 20 seconds and 105 seconds, respectively. Type electrophotographic photosensitive member was produced.
Example 3
Examples 3-1 and 3 were carried out in the same manner as in Example 1 except that the temperature of warm pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds. -2, 3-3, and 3-4 single-layer type electrophotographic photoreceptors 1 were produced.
[Comparative Example 3]
Single layers of Comparative Examples 3-5 and 3-6 in the same manner as in Example 1 except that the temperature of hot pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time conditions were 10 seconds and 95 seconds. Type electrophotographic photosensitive member was produced.
[Comparative Example 4]
As an example of a binder resin other than polycarbonate, Comparative Example 4 was performed as follows.

The binder resin of the photosensitive layer coating solution is replaced with a polyester resin (Toyobo Co., Ltd. Byron 290) to prepare a photosensitive layer coating solution, the temperature of hot pure water in which the aluminum base tube is immersed is 70 ° C., and the immersion time is 20 seconds. Except that the pulling speed was adjusted so that regions of 60 seconds and 105 seconds were formed (Ip was 4.0, 4.8, and 5.1 eV, respectively), as in Example 1, Comparative Example 4-1 , 4-2, and 4-3 were produced.
(Example 5)
As another example of the polycarbonate resin, Example 5 was performed as follows.

  A photosensitive layer coating solution was prepared by replacing the binder resin of the photosensitive layer coating solution with a bisphenol A type polycarbonate resin (Mitsubishi Gas Chemical Co., Ltd. Iupilon S-3000) having a repeating unit of the following formula (5). Except that the temperature of the pure water to be immersed is 65 ° C. and the pulling speed is adjusted so that the immersion time is 35 seconds, 50 seconds, 70 seconds and 110 seconds, respectively (Ip is 4.2, 4.6, 4 8 and 5.0 eV.) In the same manner as in Example 1, single-layer electrophotographic photoreceptors 1 of Examples 5-1, 5-2, 5-3, and 5-4 were produced.

[Comparative Example 5]
Except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds (Ip was 3.9 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 5-5 and 5-6 were prepared.
Example 6
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV.) In the same manner as in Example 5, Examples 6-1, 6-2, 6-3, and 6-4 single layer type electrophotographic photoreceptor 1 were produced.
[Comparative Example 6]
Except that the temperature of hot pure water was set to 70 ° C. and the pulling speed was adjusted so that the immersion time was 20 seconds and 105 seconds (Ip was 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 6-5 and 6-6 were prepared.
(Example 7)
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) And 5.0 eV.) In the same manner as in Example 5, single layer type electrophotographic photoreceptors 1 of Examples 7-1, 7-2, 7-3 and 7-4 were produced.
[Comparative Example 7]
Except that the temperature of hot pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 7-5 and 7-6 were produced.
(Example 8)
As another example of the polycarbonate resin, Example 8 was performed as follows.

  A photosensitive layer coating solution is prepared by replacing the binder resin of the photosensitive layer coating solution with a bisphenol C-type polycarbonate resin having a repeating unit of the following formula (6), and the temperature of hot pure water in which the aluminum base tube is immersed is 65 ° C. Except for adjusting the pulling speed so that the time is 35 seconds, 50 seconds, 70 seconds and 110 seconds respectively (Ip is 4.2, 4.6, 4.8 and 5.0 eV) In the same manner as in Example 1, single-layer electrophotographic photosensitive members 1 of Examples 8-1, 8-2, 8-3, and 8-4 were produced.

[Comparative Example 8]
Except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds (Ip was 3.9 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 8-5 and 8-6 were produced.
Example 9
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV.) In the same manner as in Example 8, single-layer electrophotographic photoreceptors 1 of Examples 9-1, 9-2, 9-3, and 9-4 were produced.
[Comparative Example 9]
Except that the temperature of hot pure water was set to 70 ° C. and the pulling speed was adjusted so that the immersion time was 20 seconds and 105 seconds (Ip was 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 9-5 and 9-6 were produced.
(Example 10)
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) And 5.0 eV.) In the same manner as in Example 8, single-layer electrophotographic photosensitive members 1 of Examples 10-1, 10-2, 10-3, and 10-4 were produced.
[Comparative Example 10]
Except that the temperature of hot pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 10-5 and 10-6 were produced.
Example 11
As an example of the different molecular weight (low molecular weight) of the polycarbonate resin, Example 11 was performed as follows.

  The binder resin of the photosensitive layer coating solution is a bisphenol Z type having a repeating unit of the following formula (7), and the photosensitive resin is replaced with a polycarbonate resin (Mitsubishi Gas Chemical Co., Ltd. Iupizeta PCZ-200) having a molecular weight of 20,000. A layer coating solution was prepared, the temperature of hot pure water in which the aluminum tube was immersed was 65 ° C., and the pulling rate was adjusted so that the immersion times were 35 seconds, 50 seconds, 70 seconds, and 110 seconds, respectively ( Ip is 4.2, 4.6, 4.8, and 5.0 eV.) In the same manner as in Example 1, single-layer type of Examples 11-1, 11-2, 11-3, and 11-4 An electrophotographic photoreceptor 1 was produced.

[Comparative Example 11]
Except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds (Ip was 3.9 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 11-5 and 11-6 were produced.
(Example 12)
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV.) In the same manner as in Example 11, single-layer electrophotographic photosensitive members 1 of Examples 12-1, 12-2, 12-3, and 12-4 were produced.
[Comparative Example 12]
Except that the temperature of hot pure water was set to 70 ° C. and the pulling speed was adjusted so that the immersion time was 20 seconds and 105 seconds (Ip was 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 12-5 and 12-6 were produced.
(Example 13)
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) In the same manner as in Example 11, single layer type electrophotographic photoreceptors 1 of Examples 13-1, 13-2, 13-3, and 13-4 were produced.
[Comparative Example 13]
Except that the temperature of hot pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). In addition, single layer type electrophotographic photosensitive members of Comparative Examples 13-5 and 13-6 were prepared.
(Example 14)
As an example of a different molecular weight (high molecular weight) of the polycarbonate resin, Example 14 was performed as follows.

  The binder resin of the photosensitive layer coating solution is a bisphenol Z type having a repeating unit of the following formula (8), and the photosensitive resin is replaced with a polycarbonate resin having a molecular weight of 80,000 (Mitsubishi Gas Chemical Co., Ltd. Iupizeta PCZ-800). A layer coating solution was prepared, the temperature of hot pure water in which the aluminum tube was immersed was 65 ° C., and the pulling rate was adjusted so that the immersion times were 35 seconds, 50 seconds, 70 seconds, and 110 seconds, respectively ( Ip is 4.2, 4.6, 4.8, and 5.0 eV, respectively). Similarly to Example 1, single layers of Examples 14-1, 14-2, 14-3, and 14-4 Type electrophotographic photoreceptor 1 was prepared.

[Comparative Example 14]
Except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds (Ip was 3.9 and 5.1 eV, respectively), and Example 14 Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 14-5 and 14-6 were produced.
(Example 15)
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV), the single-layer electrophotographic photoreceptor 1 of Examples 15-1, 15-2, 15-3, and 15-4 was produced in the same manner as Example 14.
[Comparative Example 15]
Except that the temperature of hot pure water was set to 70 ° C. and the pulling speed was adjusted so that the immersion time was 20 seconds and 105 seconds (Ip was 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 15-5 and 15-6 were produced.
(Example 16)
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) And 5.0 eV.) In the same manner as in Example 14, single-layer electrophotographic photosensitive members 1 of Examples 16-1, 16-2, 16-3, and 16-4 were produced.
[Comparative Example 16]
Except that the temperature of warm pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 16-5 and 16-6 were produced.
(Example 17)
As an example in which the ratio of the polycarbonate resin was low with respect to the material blending ratio of the photosensitive layer coating solution, Example 17 was performed as follows.

The photosensitive layer coating solution used in Example 1 was made of the same material and the blending ratio was changed as follows to prepare a photosensitive layer coating solution.
Solvent: 75% by weight of tetrahydrofuran
Binder resin: Bisphenol Z-type polycarbonate resin having a repeating unit of formula (1) (molecular weight 50,000) 8.5% by weight
Charge generation material: X-type metal-free phthalocyanine 0.5% by weight
Hole transport material: 11% by weight of styryl compound represented by formula (2)
Electron transport material: 5% by weight of azoquinone compound represented by formula (3)
Furthermore, the temperature of the pure water in which the aluminum tube is immersed is set to 65 ° C., and the pulling speed is adjusted so that the immersion time is 35 seconds, 50 seconds, 70 seconds, and 110 seconds (Ip is 4.2 for each). 4.6, 4.8, and 5.0 eV.) In the same manner as in Example 1, the single-layer type electrophotographic photoreceptor 1 of Examples 17-1, 17-2, 17-3, and 17-4 Was made.
[Comparative Example 17]
Except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds (Ip was 3.9 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 17-5 and 17-6 were produced.
(Example 18)
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV), the single-layer electrophotographic photoreceptor 1 of Examples 18-1, 18-2, 18-3 and 18-4 was produced in the same manner as in Example 17.
[Comparative Example 18]
Except that the temperature of warm pure water was set to 70 ° C. and the pulling speed was adjusted so that the immersion time was 20 seconds and 105 seconds (Ip was 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 18-5 and 18-6 were produced.
(Example 19)
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) And 5.0 eV.) In the same manner as in Example 17, single layer type electrophotographic photoreceptors 1 of Examples 19-1, 19-2, 19-3 and 19-4 were produced.
[Comparative Example 19]
Except that the temperature of hot pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 19-5 and 19-6 were produced.
(Example 20)
As an example of the case where the ratio of the polycarbonate resin is high with respect to the material mixing ratio of the photosensitive layer coating solution, Example 20 was performed as follows.

With respect to the photosensitive layer coating solution used in Example 1, the same kind of material was used, and a coating solution was prepared in which the blending ratio was changed as follows.
Solvent: 75% by weight of tetrahydrofuran
Binder resin: Bisphenol Z-type polycarbonate resin having a repeating unit of formula (1) (molecular weight 50,000) 14.5% by weight
Charge generation material: X-type metal-free phthalocyanine 0.5% by weight
Hole transport material: 7% by weight of a styryl compound represented by the formula (2)
Electron transport material: 3% by weight of azoquinone compound represented by formula (3)
Furthermore, the temperature of the pure water in which the aluminum tube is immersed is set to 65 ° C., and the pulling speed is adjusted so that the immersion time is 35 seconds, 50 seconds, 70 seconds, and 110 seconds (Ip is 4.2 for each). 4.6, 4.8, and 5.0 eV.) In the same manner as in Example 1, the single-layer electrophotographic photosensitive member 1 of Examples 20-1, 20-2, 20-3, and 20-4 is used. Was made.
[Comparative Example 20]
Except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds (Ip was 3.9 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 20-5 and 20-6 were produced.
(Example 21)
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV.) In the same manner as in Example 20, single-layer electrophotographic photoreceptors 1 of Examples 21-1, 21-2, 21-3, and 21-4 were produced.
[Comparative Example 21]
Except that the temperature of hot pure water was set to 70 ° C. and the pulling speed was adjusted so that the immersion time was 20 seconds and 105 seconds (Ip was 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 21-5 and 21-6 were produced.
(Example 22)
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) And 5.0 eV.) In the same manner as in Example 20, single-layer electrophotographic photoreceptors 1 of Examples 22-1, 22-2, 22-3, and 22-4 were produced.
[Comparative Example 22]
Except that the temperature of warm pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 22-5 and 22-6 were produced.
(Example 23)
As an example of using a different hole transport material for the material of the photosensitive layer coating solution, Example 23 was performed as follows.

With respect to the photosensitive layer coating solution used in Example 1, the hole transport material was changed to prepare a photosensitive layer coating solution having the following compounding ratio.
Solvent: 75% by weight of tetrahydrofuran
Binder resin: Bisphenol Z-type polycarbonate resin having a repeating unit of formula (1) (molecular weight 50,000) 11.5% by weight
Charge generation material: X-type metal-free phthalocyanine 0.5% by weight
Hole transport material: 9% by weight of a styryl compound represented by the following formula (9)
Electron transport material: 4% by weight of azoquinone compound represented by formula (3)

Furthermore, the temperature of the pure water in which the aluminum tube is immersed is set to 65 ° C., and the pulling speed is adjusted so that the immersion time is 35 seconds, 50 seconds, 70 seconds, and 110 seconds (Ip is 4.2 for each). 4.6, 4.8, and 5.0 eV.) In the same manner as in Example 1, single-layer electrophotographic photoreceptors 1 of Examples 23-1, 23-2, 23-3, and 23-4 are used. Was made.
[Comparative Example 23]
Except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds (Ip was 3.9 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 23-5 and 23-6 were produced.
(Example 24)
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV.) In the same manner as in Example 23, single-layer electrophotographic photosensitive members 1 of Examples 24-1, 24-2, 24-3, and 24-4 were produced.
[Comparative Example 24]
Except that the temperature of hot pure water was set to 70 ° C. and the pulling speed was adjusted so that the soaking time was 20 seconds and 105 seconds (Ip was 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 24-5 and 24-6 were produced.
(Example 25)
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) And 5.0 eV.) In the same manner as in Example 23, single-layer electrophotographic photoreceptors 1 of Examples 25-1, 25-2, 25-3, and 25-4 were produced.
[Comparative Example 25]
Except that the temperature of warm pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 25-5 and 25-6 were produced.
(Example 26)
As an example of using a different electron transport material for the material of the photosensitive layer coating solution, Example 26 was performed as follows.

With respect to the photosensitive layer coating solution used in Example 1, the electron transport material was changed to prepare a photosensitive layer coating solution having the following compounding ratio.
Solvent: 75% by weight of tetrahydrofuran
Binder resin: Bisphenol Z-type polycarbonate resin having a repeating unit of formula (1) (molecular weight 50,000) 11.5% by weight
Charge generation material: X-type metal-free phthalocyanine 0.5% by weight
Hole transport material: 9% by weight of styryl compound represented by formula (2)
Electron transport material: 4% by weight of diphenoquinone compound represented by the following formula (10)

Furthermore, the temperature of the pure water in which the aluminum tube is immersed is set to 65 ° C., and the pulling speed is adjusted so that the immersion time is 35 seconds, 50 seconds, 70 seconds, and 110 seconds (Ip is 4.2 for each). 4.6, 4.8, and 5.0 eV.) In the same manner as in Example 1, the single-layer electrophotographic photosensitive member 1 in Examples 26-1, 26-2, 26-3, and 26-4 is used. Was made.
[Comparative Example 26]
Except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds (Ip was 3.9 and 5.1 eV, respectively), and Example 26. Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 26-5 and 26-6 were produced.
(Example 27)
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV.) In the same manner as in Example 26, single-layer electrophotographic photoreceptors 1 of Examples 27-1, 27-2, 27-3, and 27-4 were produced.
[Comparative Example 27]
Except that the temperature of hot pure water was set to 70 ° C. and the pulling speed was adjusted so that the immersion time was 20 seconds and 105 seconds (Ip was 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 27-5 and 27-6 were produced.
(Example 28)
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) And 5.0 eV.) In the same manner as in Example 26, single-layer electrophotographic photoreceptors 1 of Examples 28-1, 28-2, 28-3, and 28-4 were produced.
[Comparative Example 28]
Except that the temperature of hot pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 28-5 and 28-6 were produced.
(Example 29)
As an example in the case of a different aluminum alloy, Example 29 was performed as follows with respect to the base aluminum alloy A6063 used in the above-described Examples and Comparative Examples.

In place of the aluminum base tube used in Example 1, a base tube made of a material of aluminum alloy A3003 (JIS H 4040: 1999) was used, and the temperature of hot pure water in which the aluminum base tube was immersed was 65 ° C., Except for adjusting the pulling speed so that the immersion time is 35 seconds, 50 seconds, 70 seconds and 110 seconds (Ip is 4.2, 4.6, 4.8 and 5.0 eV, respectively). In the same manner as in Example 1, single-layer electrophotographic photosensitive members 1 of Examples 29-1, 29-2, 29-3, and 29-4 were produced.
[Comparative Example 29]
Example 29 is the same as in Example 29 except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds (Ip was 3.9 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 29-5 and 29-6 were produced.
(Example 30)
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV.) In the same manner as in Example 29, single-layer electrophotographic photoreceptors 1 of Examples 30-1, 30-2, 30-3, and 30-4 were produced.
[Comparative Example 30]
Example 29 is the same as in Example 29 except that the temperature of hot pure water is 70 ° C. and the pulling rate is adjusted so that the immersion time is 20 seconds and 105 seconds (Ip is 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 30-5 and 30-6 were produced.
Example 31
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) And 5.0 eV.) In the same manner as in Example 29, single-layer electrophotographic photoreceptors 1 of Examples 31-1, 31-2, 31-3, and 31-4 were produced.
[Comparative Example 31]
Example 29 and Example 29 except that the temperature of hot pure water was 75 ° C. and the pulling rate was adjusted so that the soaking time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 31-5 and 31-6 were produced.
(Example 32)
Further, as an example in the case of a different aluminum alloy, Example 32 was performed as follows.

In place of the aluminum base tube used in Example 1, a base tube made of a material of aluminum alloy A5056 (JIS H 4040: 1999) was used, and the temperature of warm pure water in which the aluminum base tube was immersed was 65 ° C., Except for adjusting the pulling speed so that the immersion time is 35 seconds, 50 seconds, 70 seconds and 110 seconds (Ip is 4.2, 4.6, 4.8 and 5.0 eV, respectively). In the same manner as in Example 1, single-layer electrophotographic photosensitive members 1 of Examples 32-1, 32-2, 32-3, and 32-4 were produced.
[Comparative Example 32]
Except that the temperature of hot pure water was 65 ° C. and the pulling speed was adjusted so that the immersion time was 30 seconds and 115 seconds (Ip was 3.9 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 32-5 and 32-6 were produced.
(Example 33)
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV.) In the same manner as in Example 32, single-layer electrophotographic photoreceptors 1 of Examples 33-1, 33-2, 33-3 and 33-4 were produced.
[Comparative Example 33]
Except that the temperature of hot pure water was set to 70 ° C. and the pulling speed was adjusted so that the immersion time was 20 seconds and 105 seconds (Ip was 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 33-5 and 33-6 were produced.
(Example 34)
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) And 5.0 eV.) In the same manner as in Example 32, single-layer electrophotographic photoreceptors 1 of Examples 34-1, 34-2, 34-3 and 34-4 were produced.
[Comparative Example 34]
Except that the temperature of hot pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 34-5 and 34-6 were produced.
(Example 35)
As an example of using a binder resin in which different types of polycarbonate resins were mixed, Example 35 was performed as follows.

  Replacing half of the binder resin (bisphenol Z type polycarbonate resin having a repeating unit of formula (1)) in the photosensitive layer coating solution used in Example 1 with a bisphenol A type polycarbonate resin having a repeating unit of formula (5) Then, a photosensitive layer coating solution was prepared.

Furthermore, the temperature of the pure water in which the aluminum tube is immersed is set to 65 ° C., and the pulling speed is adjusted so that the immersion time is 35 seconds, 50 seconds, 70 seconds, and 110 seconds (Ip is 4.2 for each). 4.6, 4.8, and 5.0 eV.) In the same manner as in Example 1, the single-layer electrophotographic photosensitive member 1 in Examples 35-1, 35-2, 35-3, and 35-4 was used. Was made.
[Comparative Example 35]
Except for adjusting the pulling speed so that the temperature of hot pure water is 65 ° C. and the immersion time is 30 seconds and 115 seconds (Ip is 3.9 and 5.1 eV, respectively), Example 35 and Example 35 Similarly, single layer type electrophotographic photoreceptors of Comparative Examples 35-5 and 35-6 were produced.
(Example 36)
The temperature of hot pure water was set to 70 ° C., and the pulling speed was adjusted so that the immersion time was 25 seconds, 40 seconds, 60 seconds, and 100 seconds (Ip was 4.2, 4.5, and 4.8, respectively). And 5.0 eV.) In the same manner as in Example 35, single-layer electrophotographic photosensitive members 1 of Examples 36-1, 36-2, 36-3, and 36-4 were produced.
[Comparative Example 36]
Except that the temperature of hot pure water was set to 70 ° C. and the pulling speed was adjusted so that the immersion time was 20 seconds and 105 seconds (Ip was 4.0 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 36-5 and 36-6 were produced.
(Example 37)
The temperature of hot pure water was 75 ° C., and the pulling speed was adjusted so that the immersion time was 15 seconds, 30 seconds, 50 seconds, and 90 seconds (Ip was 4.2, 4.5, and 4.7, respectively) And 5.0 eV.) In the same manner as in Example 35, single-layer type electrophotographic photoreceptors 1 of Examples 37-1, 37-2, 37-3, and 37-4 were produced.
[Comparative Example 37]
Except that the temperature of hot pure water was 75 ° C. and the pulling speed was adjusted so that the immersion time was 10 seconds and 95 seconds (Ip was 4.1 and 5.1 eV, respectively). Similarly, single layer type electrophotographic photosensitive members of Comparative Examples 37-5 and 37-6 were produced.
(Evaluation)
Tables 1 to 12 show the ionization potential (Ip) on the surface of the cylindrical conductive substrate, the adhesion between the substrate and the organic photosensitive layer, and the electrical characteristics and images of the photoreceptor for each of the photoreceptors of these examples and comparative examples. The characteristics are evaluated and summarized. In the evaluation, as described in the Examples and Comparative Examples, the warm pure water immersion time differs depending on the position in one photoconductor, so a band-like region where the desired immersion time is specified is specified, and the range is limited to the specific portion. Evaluation was performed. When the surface of the cylindrical conductive substrate was treated with warm pure water, a plurality of samples were simultaneously prepared for one condition, and one of them was applied to the preparation of a sample piece for measuring the ionization potential on the substrate surface. Further, after forming the photosensitive layer on the other two substrates under the same conditions, one was used for adhesion evaluation and one was used for evaluation of electrical characteristics and image characteristics.

  The ionization potential was obtained by subjecting the surface to a desired immersion time condition after performing a surface treatment with warm pure water (sample piece approximately 20 mm × 20 mm), an atmospheric photoelectron spectrometer (AC-2 (manufactured by Riken Keiki Co., Ltd.)), and a light source light amount of 60 nW ).

  Evaluation of adhesion strength is based on JIS H8504, forming a 1mm square, 10x10 mass (100 mass) cross hatch on the organic photosensitive layer, and testing the peel strength with adhesive tape (Nichiban CT405AP-24). It went by. The number of peeled cells in 100 cells was counted and evaluated.

As an electrical property, using a photoconductor electrical property evaluation apparatus, the charge retention rate Vk5 (the surface of the photoconductor is charged to a potential of 600 V, and the dark decay potential (Vd) after 5 seconds is measured. The higher the Vd potential, the better. ) And residual potential Vr (surface potential when a photosensitive member charged to 600 V is irradiated with exposure light having a wavelength of 780 nm and a light quantity of 1 μJ / cm ^2. The lower the Vr potential, the better.) Evaluation was made. The image characteristics were evaluated by a positively charged laser printer. A white solid image and a black solid image were output, limited to the portion corresponding to the position of the desired hot pure water immersion condition, and evaluated by the presence or absence of black spots in the white solid image and the presence or absence of white spots in the black solid image. The anti-filming property was evaluated by a running test of 10,000 sheets with a positively charged laser printer. The filming state on the surface of the photosensitive layer after running was judged visually. In each evaluation result, a double circle indicates excellent, a circle indicates good, a triangle indicates acceptable, and a cross indicates impossibility.

  As seen in Table 1, the photoconductors of Examples 1-1, 1-2, 1-3, and 1-4 were peeled in the adhesion strength test by cross-hatch (hereinafter referred to as “cross-hatch test”). Was 6 or less, showing good adhesion strength, and also good results in electrical characteristics and image characteristics. In particular, the photoconductors of Examples 1-2, 1-3, and 1-4 exhibited a very excellent adhesion strength with a peel number of 0, and excellent results in both electrical characteristics and image characteristics.

  On the other hand, the photoconductor of Comparative Example 1-5 has good electrical characteristics and image characteristics, but has a large number of peels of 65 in the cross-hatch test and poor adhesion. In such a photoreceptor, when it is repeatedly subjected to stress in the electrophotographic process, film peeling progresses at the interface between the substrate and the photosensitive layer, and there is a possibility that electric characteristics and image characteristics may be impaired. This is probably because the treatment time was short with respect to 65 ° C. hot pure water, and the formation of the hydrated oxide film was insufficient. In addition, the photoconductor of Comparative Example 1-6 had good adhesion strength but was inferior in electrical characteristics and image characteristics. This is probably because the hydrated oxide film became excessively thick due to the treatment with warm pure water for a long time. An excessively thick hydrated oxide film hinders the electrical characteristics and image characteristics of the photoreceptor.

  The photoreceptors of Examples 2-1, 2-2, 2-3, 2-4 had a peel number of 5 or less, and were good results with respect to adhesion strength, electrical characteristics, and image characteristics. In particular, the photoreceptors of Examples 2-2, 2-3, and 2-4 had a peel number of 0 and exhibited very excellent adhesion strength, and showed excellent results in both electrical characteristics and image characteristics.

The photoreceptor of Comparative Example 2-5 has drawbacks in adhesion strength and electrical characteristics, and the photoreceptor of Comparative Example 2-6 has difficulties in electrical characteristics and image characteristics, although the adhesion strength is excellent.
The photoreceptors of Examples 3-1, 3-2, 3-3, and 3-4 had a peel number of 4 or less, and the adhesion strength, electrical characteristics, and image characteristics were satisfactory. In particular, the photoreceptors of Examples 2-2, 2-3, and 2-4 had a peel number of 0 and exhibited very excellent adhesion strength, and showed excellent results in both electrical characteristics and image characteristics.

The photoreceptor of Comparative Example 3-5 has difficulties in adhesion strength and electrical characteristics, and the photoreceptor of Comparative Example 3-6 has difficulties in electrical characteristics and image characteristics although it has excellent adhesion strength.
From the above results, the treatment conditions of 35 to 110 seconds at a pure water temperature of 65 ° C., 25 to 100 seconds at 70 ° C., and 15 to 90 seconds at 75 ° C. are good. Therefore, by carrying out the warm pure water treatment of the aluminum substrate from the upper end to the lower end of the substrate so as to apply to the condition of the range 1 shown in the graph of FIG. 4, and forming the organic photosensitive layer containing the polycarbonate resin on this surface, It was revealed that good results could be obtained with the evaluation items. In particular, it was found that the best results were obtained with respect to adhesion strength, electrical characteristics, and image characteristics by setting the processing conditions to the range 2 shown in FIG.

  This is because a hydrated oxide film under suitable conditions that has sufficient adhesion strength with the organic photosensitive layer and does not interfere with electrical characteristics and image characteristics is formed on the surface of the cylindrical conductive substrate under the above-described hot pure water treatment conditions. It is thought that Such a hydrated oxide film is defined by the ionization potential (Ip), and as shown in Table 1, the preferred range is 4.2 to 5.0 eV, more preferably 4.5 to 5.0 eV. is there. With respect to range 1 in FIG. 4, when the temperature of the pure water is less than 65 ° C. on the low temperature side, the rate of formation of the hydrated oxide film is slow, which is not preferable in the manufacturing process. On the other hand, when the temperature exceeds 75 ° C. on the high temperature side, convection of pure water is likely to occur in the pure water tank, resulting in uneven temperature distribution of pure water, which is not preferable in terms of management of surface treatment quality.

  Next, the photoreceptors of Comparative Examples 4-1, 4-2, and 4-3 had a peel number of 0 and good adhesion strength. Moreover, the electrical characteristics and image characteristics were also good results. Therefore, the claim of Ip of the present invention does not make sense for a resin such as a polyester resin that has inherently strong adhesion strength.

  As can be seen in Table 2, the evaluation results of Examples 5-1 to 4, 6-1 to 4, 7-1 to 4 and Comparative Examples 5-5 to 6, 6-5 to 6, 7-5 to 6 Shows that the same result is obtained even when the bisphenol Z type of polycarbonate is changed to the bisphenol A type.

  Moreover, as seen in Table 3, Examples 8-1 to 4, 9-1 to 4, 10-1 to 4 and Comparative Examples 8-5 to 6, 9-5 to 6, 10-5 to 6 The evaluation result shows that the same result is obtained even when the bisphenol Z type of the polycarbonate is changed to the bisphenol C type.

  Furthermore, as seen in Table 4, Examples 11-1 to 4, 12-1 to 4, 13-1 to 4 and Comparative Examples 11-5 to 6, 12-5 to 6, and 13-5 to 6 were used. The evaluation result shows that the same result is obtained even when the bisphenol Z type of polycarbonate is changed to a low molecular weight type.

  In addition, as seen in Table 5, Examples 14-1 to 4, 15-1 to 4, 16-1 to 4 and Comparative Examples 14-5 to 6, 15-5 to 6, 16-5 to 6 These evaluation results show that the same result is obtained even when the bisphenol Z type of polycarbonate is changed to a high molecular weight type.

  Moreover, as seen in Table 6, Examples 17-1 to 4, 18-1 to 4, 19-1 to 4 and Comparative Examples 17-5 to 6, 18-5 to 6, 19-5 to 6 The evaluation result shows that the same result is obtained even when the content of the polycarbonate resin is reduced from 11.5 wt% to 8.5 wt%.

  Furthermore, as seen in Table 7, Examples 20-1 to 4, 21-1 to 4, 222-1 to 4 and Comparative Examples 20-5 to 6, 21-5 to 6, 22-5 to 6 The evaluation result shows that the same result is obtained even when the content of the polycarbonate resin is increased from 11.5 wt% to 14.5 wt%.

  In addition, as seen in Table 8, Examples 23-1 to 4, 24-1 to 4, 25-1 to 4 and Comparative Examples 23-5 to 6, 24-5 to 6, 25-5 to 6 These evaluation results show that the same result can be obtained even if the hole transport material is replaced with the formula (9).

  Moreover, as seen in Table 9, Examples 26-1 to 4, 27-1 to 4, 28-1 to 4 and Comparative Examples 26-5 to 6, 27-5 to 6, and 28-5 to 6 were used. The evaluation result shows that the same result is obtained even when the electron transporting material is replaced with the formula (10).

  Furthermore, as seen in Table 10, Examples 29-1 to 4, 30-1 to 4, 31-1 to 4 and Comparative Examples 29-5 to 6, 30-5 to 6, 31-5 to 6 The evaluation result shows that the same result is obtained even when the aluminum alloy of the cylindrical conductive substrate is changed to the A3003 material.

  In addition, as seen in Table 11, Examples 32-1 to 4, 33-1 to 4, 34-1 to 4 and Comparative Examples 32-5 to 6, 33-5 to 6, 34-5 to 6 These evaluation results show that the same result is obtained even when the aluminum alloy of the cylindrical conductive substrate is changed to the A5056 material.

  And as seen in Table 12, Examples 35-1 to 4, 36-1 to 4, 37-1 to 4 and Comparative Examples 35-5 to 6, 36-5 to 6, 37-5 to 6 The evaluation result shows that the same result is obtained even when different types of polycarbonate resins are used in combination.

  As shown in Tables 1 to 12, the polycarbonate resin shows very excellent results with respect to filming resistance, which is an important item of printing durability. Therefore, the present invention for ensuring the adhesion strength of a single layer type electrophotographic photoreceptor using a polycarbonate resin as a binder resin is very effective.

DESCRIPTION OF SYMBOLS 1 Single layer type electrophotographic photosensitive member 10 Cylindrical conductive base | substrate 20 Organic photosensitive layer 30 Protective layer

Claims (8)

A cylindrical conductive substrate made of aluminum or an aluminum alloy and having an ionization potential (Ip) on its surface of 4.2 to 5.0 eV;
And an organic photosensitive layer formed on the surface of the cylindrical conductive substrate and containing a polycarbonate resin as a binder resin. The single-layer electrophotographic photosensitive member according to claim 1, wherein the ionization potential (Ip) is 4.5 to 5.0 eV. The single-layer type according to claim 1, wherein all surfaces of the cylindrical conductive substrate are immersed in warm pure water under the conditions of temperature and time included in the range 1 shown in FIG. Electrophotographic photoreceptor. 3. The single layer type according to claim 2, wherein all surfaces of the cylindrical conductive substrate are immersed in warm pure water under the conditions of temperature and time included in the range 2 shown in FIG. Electrophotographic photoreceptor. 2. The single layer type electrophotographic photosensitive member according to claim 1, wherein the aluminum alloy is A6000 series, A3000 series or A5000 series (JIS H 4040: 1999). 2. The single-layer electrophotographic photosensitive member according to claim 1, wherein the polycarbonate resin is one of bisphenol Z type, A type and C type, or a mixture thereof. A step of immersing all surfaces of a cylindrical conductive substrate made of aluminum or an aluminum alloy in warm pure water under the conditions of temperature and time included in range 1 shown in FIG. 4, and an organic photosensitive layer containing polycarbonate resin as a binder resin Forming on the surface of the cylindrical conductive substrate. A method for producing a single-layer electrophotographic photosensitive member, comprising: A step of immersing all surfaces of a cylindrical conductive substrate made of aluminum or an aluminum alloy in warm pure water under the conditions of temperature and time included in range 2 shown in FIG. 4, and an organic photosensitive layer containing polycarbonate resin as a binder resin Forming on the surface of the cylindrical conductive substrate. A method for producing a single-layer electrophotographic photosensitive member, comprising: