JPH0477760A - Electrifying member - Google Patents

Abstract

PURPOSE:To stably obtain high-grade images which are free from image dotty fogging by the nonuniformity of electrification and image defects by the discharge breakdown of a photosensitive body by providing a resin layer contg. a copolymer of alkyl vinyl ether and maleic anhydride on a conductive elastic layer. CONSTITUTION:This electrifying member is made into the three-layered constitution consisting of the conductive elastic layer 2 provided on a conductive base 1a and further, the resin layer 3 contg. the copolymer of alkyl vinyl ether and maleic anhydride on the elastic layer 2. Methyl vinyl ether, ethyl vinyl ether, isopropyl vinyl ether, hexyl vinyl ether, and dodecyl vinyl ether are usable as the alkyl vinyl ether. The electrifying member having the resin layer contg. the copolymer of the alkyl vinyl ether and the maleic anhydride has the low adhesiveness to the electrophotographic sensitive body and has resilience as well and, therefore, the member imparts high image quality, lessens the contamination with toners, and lessens the fluctuation in the volumetric resistance of the resin layer even at and under a low temp. and low humidity. This member is thus usable as the stable electrifying member.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a charging member, and particularly to a charging member used for primary charging, transfer charging, and static elimination charging in electrophotography.

[Prior Art] The charging process in an electrophotographic process using an electrophotographic photoreceptor has conventionally applied a high voltage (DC) to a metal wire.
5 to 8 kV) is applied, and charging is performed by the generated corona. However, with this method, when corona occurs, corona products such as ozone and NOx alter the surface of the photoreceptor, causing image blurring and deterioration, and dirt on the wires affects image quality, resulting in white spots and black lines in the image. There were other problems. On the other hand, in terms of electric power, the current flowing toward the photoreceptor is
The amount was only ~30%, and most of it flowed to the shield plate, making it ineffective as a charging means.

In order to compensate for these drawbacks, many methods of direct charging have been researched and proposed (Japanese Patent Application Laid-Open No. 57178267, JP 56-104351, JP 58-40
566, JP-A-58-139156, JP-A-58-150975, etc.). However, in reality, even if the photoreceptor is charged by the contact charging method as described above, the surface of the photoreceptor is not uniformly charged at each part, and uneven charging occurs. For example, in the reversal development method, even if a process below photoimage exposure is applied to a photoconductor with spotty charging unevenness, the output image will be a spotty black dot image corresponding to the spotty charging unevenness, whereas in the regular development method, the output image will be a spotty black dot image corresponding to the spotty charging unevenness. In contrast to the unevenness, the image becomes a speckled white dot image, making it impossible to obtain a high-quality image.

Further, although there are many proposals for the direct charging method, there is no market experience at all. The reason for this is the uniformity of charging,
Examples of such problems include the occurrence of discharge dielectric breakdown of the photoreceptor due to direct voltage application. For example, in the case of a cylindrical photoreceptor, one breakdown point due to discharge dielectric breakdown has the disadvantage that the entire charge in the axial direction flows to the breakdown point and is no longer charged.

[Problems to be Solved by the Invention] In order to prevent this dielectric breakdown, a method of forming a resin layer on the surface has also been reported (JP-A-1205180, JP-A-1-211779).

However, these materials also exhibit large fluctuations in resistance under low temperature and low humidity conditions, resulting in unstable charging properties, and when used in close contact with an organic photoreceptor, the resins on the surfaces of the organic photoreceptor and the charging member may interact with each other. It had defects such as melting and sticking.

Therefore, it is an object of the present invention to provide a charging device that can solve the above-mentioned drawbacks and stably supply high-quality images without causing spot fog due to non-uniform charging or image defects due to discharge dielectric breakdown of the photoreceptor. The goal is to provide parts.

[Means for Solving the Problems] That is, the present invention provides a charging member having a conductive elastic layer on a conductive support, wherein the conductive elastic layer contains a copolymer of alkyl vinyl ether and maleic anhydride. This is a charging member characterized by having a resin layer.

The present invention will be explained in more detail below.

As shown in FIG. 1, the charging member of the present invention includes a conductive elastic layer 2 provided on a conductive support la, and further contains a copolymer of alkyl vinyl ether and maleic anhydride on the elastic layer 2. The basic configuration is a three-layer structure in which a resin layer 3 is provided.

The copolymer of alkyl vinyl ether and maleic anhydride used in the present invention is produced by condensation using a known method.

In the present invention, as the alkyl vinyl ether, for example, methyl vinyl ether, ethyl vinyl ether, isopropyl vinyl ether, hexyl vinyl ether, and dodecyl vinyl ether can be used. Generally, as the molecular weight increases, the copolymerizability with maleic anhydride or the film-forming ability of the copolymer tends to decrease, so the number of carbon atoms in the alkyl group of the alkyl vinyl ether is preferably 12 or less, particularly preferably 6 or less.

Specific examples of copolymers of alkyl vinyl ether and maleic anhydride are shown below.

Methyl vinyl ether/maleic anhydride copolymer -tcI□-CHFV-+-CI -CH story Ethyl vinyl ether/maleic anhydride copolymer Isopropyl vinyl ether/maleic anhydride copolymer (m and n are integers) Further resin layer A binder resin may be added. However, the amount of binder resin added is 30% by weight based on the total resin.
The following are preferred. Binder resins in the resin layer include acrylic resins such as polymethyl methacrylate and polybutyl methacrylate, polyvinyl butyral, polyvinyl acecool, polyarylate, polycarbonate,
Examples include phenoxy resin, polyvinyl acetate, and polyvinylpyridine.

Conventional charging members have surfaces made of rubber or polyurethane, so if they come into contact with an electrophotographic photoreceptor, the photoreceptor and charging member may stick together, or if the surface is hard, wrinkles may occur. This caused image defects.

In contrast, the charging member having a resin layer containing a copolymer of alkyl vinyl ether and maleic anhydride of the present invention has low adhesion to the electrophotographic photoreceptor and is flexible, so it can produce high-quality images. It can be used as a stable charging member, with little toner staining and little variation in the volume resistivity of the resin layer even under low temperature and low humidity conditions.

The thickness of the resin layer is 5 to 500 μm, especially 20 to 200 μm.
A range of is preferred.

The volume resistivity of the resin layer is preferably in the range of 106 to 10"Ωcm. Also, as shown in Japanese Patent Application No. 62-230334, the volume resistivity of the resin layer is lower than that of the lower conductive elastic layer in contact with the resin layer. It is preferable that the volume resistivity is larger than that of .

The volume resistivity of the elastic layer 2 is preferably in the range of 10' to 10''Ω'cm, particularly 10'' to 1010 Ω'cm.The elastic layer 2 is made of metals such as aluminum, iron, copper, polyacetylene 1, polypyrrole, polythiophene, etc. Rubber or plastic elastomer treated to be conductive by dispersing conductive polymer, carbon, metal, etc. Rubber or plastic elastomer whose surface is laminated and coated with metal or other conductive substance can be used.

Moreover, this elastic layer 2 may have a multilayer structure with separate functions as required. As the conductive support 1a,
Iron, copper, stainless steel, etc. can be used.

Further, as shown in FIG. 2, a protective layer 4 may be provided on the surface of the charging member to protect the charging member. This protective layer is formed of a resin layer, and insoluble resin powder 5 may be mixed therein to control the conductivity and the surface roughness of the charging member.

In the case of a blade-shaped charging member as shown in FIG. 3, a conductive elastic layer 2 is provided on the conductive sheet metal 1b, and a resin layer 3
will be established.

Further, a protective layer may be provided.

The charging member may have any shape such as a roller shape or a blade shape, but a roller shape is preferable in terms of uniform charging.

Electrophotographic photoreceptors basically have a structure in which a photosensitive layer is provided on a conductive support. As the conductive support, materials that are conductive themselves such as aluminum, aluminum alloy, stainless steel, chromium, titanium, etc. can be used. In addition, aluminum, aluminum alloy, indium oxide-tin oxide alloy, etc. can be used. The conductive support or plastic has a layer formed by vacuum deposition, a support in which plastic or paper is impregnated with conductive particles (e.g. carbon black, tin oxide particles, etc.) together with a suitable binder, or a conductive binder. Plastic or the like can be used.

A subbing layer having barrier and adhesive functions can also be provided between the conductive support and the photosensitive layer.

The subbing layer can be formed from casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, polyamide, polyurethane, gelatin, aluminum oxide, or the like. The thickness of the undercoat layer is suitably 5 μm or less, preferably 0.5 to 3 μm. In order for the undercoat layer to perform its function, it is desirable that the undercoat layer has a resistance of 10 7 Ω·cm or more.

The photosensitive layer is formed, for example, by coating a photoconductor such as an organic photoconductor, amorphous silicon, selenium, etc. together with a binder if necessary, or by vacuum deposition. Furthermore, when using an organic photoconductor, a photosensitive layer consisting of a combination of a charge generation layer that generates charge carriers upon exposure to light and a charge transport layer that has the ability to transport the generated charge carriers can also be effectively used.

The charge generating layer may be formed by depositing one or more charge generating materials such as azo pigments, quinone pigments, quinone anine pigments, perylene pigments, indigo pigments, bisbenzimidazole pigments, phthalocyanine pigments, and quinacridine pigments, or by depositing a suitable material. It can be formed by dispersing and coating (can be formed without the C binder together with the binder).

The binder can be selected from a wide range of insulating resins or organic photoconductive polymers. For example, insulating resins include polyvinyl butyral, polyarylate (condensation polymer of bisphenol A and phthalic acid, etc.), polycarbonate, polyester, phenoxy resin, acrylic resin, polyacrylamide resin, polyamide, cellulose resin, urethane resin, epoxy resin, Examples include casein and polyvinyl alcohol. Further, examples of the organic photoconductive polymer include carbazole, polyvinylanthracene, polyvinylpyrene, and the like.

The thickness of the charge generation layer is 0.01 to 15 μm, preferably 0.01 to 15 μm.
．． 05 to 5 μm, and the weight ratio of the charge generation layer to the binder is 10:1 to 1:20.

The solvent used in the paint for the charge generation layer is selected based on the solubility and dispersion stability of the resin and charge transport material used. Examples of organic solvents include alcohols, sulfoxides, ethers, esters, and aliphatic solvents. Halogenated hydrocarbons or aromatic compounds can be used.

Coating can be done by dip coating method, spray coating method,
It can be carried out using a coating method such as Mayer bar coating or blade coating.

The charge transport layer is formed by dissolving a charge transport material in a film-forming resin. Examples of organic charge transport materials used in the present invention include hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds,
Examples include thiazole compounds and triarylmethane compounds. These charge transport materials can be used alone or in combination of two or more.

Examples of binders used in the charge transport layer include phenoxy resin, polyacrylamide, polyvinyl butyral, polyarylate, polysulfone, polyamide, acrylic resin, acrylonitrile resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, phenolic resin, and epoxy. Resin, polyester, alkyd resin, polycarbonate, polyurethane or two of the repeating units of these resins
copolymers containing more than one, such as styrene-butadiene copolymers, styrene-acrylonitrile copolymers,
Examples include styrene-maleic acid copolymer. It can also be selected from organic photoconductive polymers such as poly-N-vinylcarbazole, polyvinylanthracene, and polyvinylpyrene.

The thickness of the charge transport layer is 5 to 50 μm, preferably 8 to 20 μm.
μ town, and the weight ratio of charge transport material and binder is 5:1
~1:5, preferably 3:1 to 1:3. The coating method described above can be used for coating.

Furthermore, dyes, pigments, organic charge transport substances, and the like are generally susceptible to ultraviolet rays, ozone, stains caused by oil, and metals, so a protective layer may be provided as necessary. In order to form an electrostatic latent image on this protective layer, the surface resistivity is 1011.
It is desirable that it is Ω or more.

The protective layer of the photoreceptor is made of polyvinyl butyral, polyester, polycarbonate, acrylic resin, methacrylic resin,
It can be formed by dissolving a resin such as nylon, polyimide, polyarylate, polyurethane, styrene-butadiene copolymer, styrene-acrylic acid copolymer, styrene-acrylonitrile copolymer, etc. in a suitable organic solvent on the photosensitive layer and drying it. . At this time, the thickness of the protective layer is generally in the range of 0.05 to 20 Im.

This protective layer may contain an ultraviolet absorber or the like.

The charging member of the present invention can be applied to, for example, an electrophotographic apparatus as shown in FIG. This device includes a primary charging member 6 and an image exposure element 1 on the circumferential surface of an electrophotographic photoreceptor 12.
517, a developing means 8, a corona charger 9 for transfer charging, a cleaning means 10, and a pre-dipping tip means 11 are arranged.

The primary charging member 6 placed in contact with the electrophotographic photoreceptor 2" is applied with an external voltage (for example, 200V or more
A pulsating current voltage, which is a superimposition of a DC voltage of 0 V or less and an AC voltage of 4000 V or less between peaks, is applied to charge the surface of the electrophotographic photoreceptor 12, and the image exposure means 7 images the image on the document onto the photoreceptor. and forms an electrostatic latent image. Next, by attaching the developer in the developing means 8 to the photoreceptor, the electrostatic latent image on the photoreceptor is developed (visualized), and the developer on the photoreceptor is transferred to a corona charger for transfer charging. 9 transfers the developer onto a transfer member 13 such as paper, and a cleaning means 10 collects the developer remaining on the photoreceptor without being transferred to the paper during transfer.

Although an image can be formed by such an electrophotographic process, if there is a residual charge remaining on the photoreceptor, the photoreceptor is exposed to light by the pre-exposure means 11 before the next charging to remove the residual charge. It is better to eliminate static electricity.

When the charging member of the present invention is used for transfer charging, it can be applied to, for example, an electrophotographic apparatus as shown in FIG. In this apparatus, a corona charger 4 for primary charging, an image exposure means 7, a developing means 8, a charging member 15 for transfer charging, a cleaning means 10, and a pre-exposure means 11 are arranged on the circumferential surface of an electrophotographic photoreceptor 120. There is.

A voltage (for example, a DC voltage of 400 to 100 O
V) can be applied to transfer the developer on the electrophotographic photoreceptor to a transfer member such as paper.

When the charging member of the present invention is used for static elimination charging, it can be applied to, for example, an electrophotographic apparatus as shown in FIG. In this apparatus, a corona charger 14 for primary charging, an image exposure means 7, a developing means 8, a corona charger 9 for transfer charging, and a cleaning means 10 are arranged on the circumferential surface of an electrophotographic photoreceptor 12.

A voltage (for example, an AC peak-to-peak voltage of 500 to 500
2000V) can be applied to remove the electric charge on the electrophotographic photoreceptor.

By applying the charging member of the present invention to an electrophotographic photoreceptor having a photosensitive layer containing an organic photoconductor, which easily deteriorates in terms of mechanical strength and chemical stability, its characteristics can be clearly exhibited. can do.

In the present invention, the method for installing the charging member in contact with the photoreceptor is not limited to a specific method.
Any method of movement such as rotation in the same direction as the photoreceptor or in the opposite direction can be used. Furthermore, it is also possible to cause the charging member to function as a developer cleaning device on the photoreceptor.

Regarding the voltage applied to the charging member and the application method in the direct charging of the present invention, it depends on the specifications of each electrophotographic device, but in addition to the method of instantly applying the desired voltage, there are also methods for protecting the photoreceptor. A method can be adopted in which the applied voltage is increased stepwise and the voltage is applied in the order of alternating current or alternating current.

When the charging member of the present invention is used for primary charging of an electrophotographic device, it is necessary to superimpose a DC voltage and an AC voltage on the electrophotographic photoreceptor in the image output area.

When primary charging is applied only with DC voltage, uniform charging cannot be achieved.

When used for transfer charging, a DC voltage alone or a DC voltage and an AC voltage may be superimposed.

When used for static elimination charging, it is necessary to apply only an alternating current voltage.

Further, in the present invention, processes such as image exposure, development, and cleaning can be performed using any method known in the field of electrostatic photography, and are not limited to a specific type of developer.

The charging member of the present invention can be used not only in copying machines but also in electrophotographic applications such as laser printers, CRT printers, electrophotographic plate-making systems, and facsimile machines having a receiving means for receiving image information from a remote terminal. can.

[Example] The present invention will be explained below using examples.

Example 1 As a conductive support, 60φ×260 with a wall thickness of 0.5 mm
A mm aluminum cylinder was prepared.

Copolymerized nylon (product name: CM8000, manufactured by Toshi ■)
Part 4 and Type 8 nylon (trade name: Laccamite 5
003, manufactured by Dainippon Ink ■) 4 parts with 50 parts of methanol,
It was dissolved in 50 parts of n-butanol and applied on the above support by dip coating to form a 0.6 μm thick undercoat layer.

10 parts of a disazo pigment with the following structural formula, and polyvinyl butyral resin (product name: S-LEC B)
10 parts of M2 (manufactured by Tanemizu Kagaku ■), 12 parts of cyclohexanone
It was dispersed for 10 hours in a sand mill with 0 parts. 30 parts of methyl ethyl ketone was added to the dispersion and coated on the undercoat layer to form a charge generation layer with a thickness of 0.15 μm.

Polycarbonate 1-Z resin with a weight average molecular weight of 120,000 (
(manufactured by Mitsubishi Gas Chemical Co., Ltd.) was prepared and dissolved in 80 parts of monochlorobenzene together with 10 parts of a hydrazone compound 2H6 having the following structural formula. This was coated on the charge generation layer to form a charge transport layer with a thickness of 16 μm, and electrophotographic photoreceptor No. 1 was manufactured.

Next, conductive carbon 5 was added to 100 parts by weight of chloroprene rubber.
Melt and knead the weight parts and form a φ8 piece at the center as a conductive support.
φ20X 2 through the stainless steel shaft of X 26[]mm
It was molded to have a thickness of 40 mm, and a conductive elastic layer of a roller-shaped charging member was provided.

The volume resistance of the conductive elastic layer of this charging member is determined at a temperature of 22
When measured in an environment of ℃ and 60% humidity, it is 3 x 10'Ω・Cl
It is 11.

Next, methyl vinyl ether/maleic anhydride copolymer (
Product name: GANTREZ AN-139, GAF Company)
5 parts by weight were dissolved in 10 parts by weight of a mixed solvent of ethyl alcohol: NN'-dimethylformamide = 5 = 5, and the solution was dip-coated on the conductive elastic layer of the charging member to give a film thickness of 20 OLlm after drying. A resin layer was provided to produce a roller-shaped charging member. A resin layer was similarly provided on an aluminum sheet, and the volume resistance was measured.

This charging member is connected to a normal development type copying machine PC as shown in Fig. 3.
It is installed in place of the -20 (manufactured by Canon) corona charger, and is driven to rotate with the electrophotographic photosensitive member. Potential measurements and images of dark potential and bright potential of the body were examined.

The results are shown in Table 1.

Furthermore, the volume resistance of the resin layer of the charging member, the potential characteristics and the image when this charging member is attached to a normal development type copying machine were similarly examined under a low temperature and low humidity condition of a temperature of 15°C and a humidity of 10%. It was shown to.

Example 2 A conductive elastic layer of a charging member was prepared in the same manner as in Example 1.

Next, methyl vinyl ether/maleic anhydride copolymer (
Product name: GANTREZ AN-149, GAF Company)
5 parts by weight of methyl alcohol: Kano: N,N'-dimethylformamide = 3:5:2 mixed solvent 10
A roller-shaped charging member was manufactured by dissolving the resin in parts by weight and applying it by dip coating on the conductive elastic layer of the charging member to form a resin layer having a thickness of 200 μm after drying.

This was evaluated in the same manner as in Example 1 and is shown in Table 1.

Example 3 A conductive elastic layer of a charging member was prepared in the same manner as in Example 1.

Next, methyl vinyl ether/maleic anhydride copolymer (
AN-139, GAF) and 5 parts by weight of polyvinylpyronthone (product name: PVP-90.GAF) in 20 parts by weight of a mixed solvent of ethyl alcohol: N,N'-dimethylformamide = 5:5. was dissolved in the above-mentioned electrically conductive elastic layer, and dip-coated on the conductive elastic layer of the charging member, and after drying, the film thickness was 2.
A resin layer of 0.00 If m was provided to produce a roller-shaped charging member.

This was evaluated in the same manner as in Example 1 and is shown in Table 1.

Example 4 A conductive elastic layer of a charging member was prepared in the same manner as in Example 1.

Next, methyl vinyl ether/maleic anhydride copolymer (
AN-1,49, GAF) 5 parts by weight and polyvinyl birod: / f PVP- to 90. GAF) was dissolved in 20 parts by weight of a mixed solvent of methyl alcohol: MEK:NN-dimethylformamide = 375:2, and applied by dip coating onto the conductive elastic layer of the charging member, and after drying, the film was formed. A 200 μm thick resin layer was provided to produce a roller-shaped charging member.

This was evaluated in the same manner as in Example 1 and is shown in Table 1.

Comparative Example 1 A conductive elastic layer of a charging member was prepared in the same manner as in Example 1.

Next is nylon 6-66-10-12. ] O-heavy weight methanol 90 parts by weight was dissolved and applied by dip coating on the conductive elastic layer of the charging member, and after drying, a resin layer with a film thickness of 200 μm was provided to produce a roller-shaped charging member.

This was evaluated in the same manner as in Example 1 and is shown in Table 1.

Comparative Example 2 A conductive elastic layer of a charging member was prepared in the same manner as in Example 1.

Next, 10 parts by weight of methoxymethylated nylon 6 (methoxymethylation rate 25%) was dissolved in 90 parts by weight of methanol, and the solution was dip-coated onto the conductive elastic layer of the charging member to give a film thickness of 200 μm after drying. A resin layer was provided to produce a roller-shaped charging member.

This was evaluated in the same manner as in Example 1 and is shown in Table 1.

Comparative Example 3 A conductive elastic layer of a charging member was prepared in the same manner as in Example 1.

Next, polyester polyol (product name: Niboran 12
1. 8 parts by weight of Nippon Polyurethane ■ and 2 parts by weight of toluylene diisocyanate were dissolved in 90 parts by weight of n-butanol, and the solution was dip-coated onto the conductive elastic layer of the charging member to give a film thickness of 200 μm after drying. A roller-shaped charging member was manufactured by providing a resin layer.

This was evaluated in the same manner as in Example 1 and is shown in Table 1.

Comparative Example 4 A conductive elastic layer of a charging member was prepared in the same manner as in Example 1.

Next, 10 parts by weight of silicone RTV rubber was dissolved in 90 parts by weight of toluene, and the solution was dip coated onto the conductive elastic layer of the charging member, and after drying, a resin layer with a film thickness of 200 μm was provided, and a roller-shaped charging member was prepared. was manufactured.

This was evaluated in the same manner as in Example 1 and is shown in Table 1.

Example 1. ．． As can be seen by comparing Comparative Examples 1 and 2 with Comparative Examples 1 and 2, the present invention can prevent image defects such as wavy fog caused by hardening of the resin layer at low temperature and low humidity.

Furthermore, as can be seen by comparing Examples 1, 2, and 3.4 with Comparative Example 3.4, it is possible to prevent the charging member from fusing with the photoreceptor and to suppress the occurrence of horizontal streak images.

Although the polyurethane resin layer has a high volume resistance as in Comparative Example 3, an appropriate volume resistance can be obtained by containing the alkyl vinyl ether/maleic anhydride copolymer as in Examples 1, 2, and 3.4. , exhibiting more useful charging properties.

Example 5 Below, the characteristics as a transfer charger were investigated.

A photoreceptor was produced in the same manner as in Example 1.

Next, 100 parts by weight of chloroprene rubber was melt-kneaded with 5 parts by weight of conductive carbon, and a stainless steel shaft of 8 mm in diameter x 260 mm was passed through the center and formed into a shape of 30 mm in diameter x 240 mm, and the conductive elastic layer of the roller shape transfer charging member was formed. has been established.

The volume resistance of this transfer charging member was determined at a temperature of 22°C and a humidity of 60°C.
% environment, it is 4 x 10'Ω・cm.

Next, methyl vinyl ether/maleic anhydride copolymer (
AN-139, GAF) 5 parts by weight was added to 1 part of a mixed solvent of ethyl alcohol:NN'-dimethylformamide-5:5.
0 parts by weight and dip-coated on the conductive elastic layer of the transfer charging member,
After drying, a resin layer having a thickness of 100 μm was provided to produce a roller shape transfer charging member.

This transfer charging member was installed in place of the transfer corona charger of a normal development type copying machine PC20 (manufactured by Canon), a direct current of -500 V was applied for transfer charging, and the state of the image and the transfer charging member was examined.

The results are shown in Table 2.

Furthermore, the image and the state of the transfer charging member when the transfer charging member was attached to a normal development type copying machine under a low temperature and low humidity condition of 15° C. and 10% humidity were investigated and are shown in Table 2.

Example 6 A conductive elastic layer of a transfer charging member was prepared in the same manner as in Example 5.

Next, methyl vinyl ether/maleic anhydride copolymer +
AN-149, GAF) 5 parts by weight of methyl alcohol: MEKNN'-dimethylformamide = 3:
5: Dissolved in 10 parts by weight of a mixed solvent of 2, dip coated on the conductive elastic layer of the transfer charging member,
After drying, a resin layer having a thickness of 100 μm was provided to produce a roller shape transfer charging member.

This was evaluated in the same manner as in Example 5 and is shown in Table 2.

Example 7 A conductive elastic layer of a transfer charging member was prepared in the same manner as in Example 5.

Next, methyl vinyl ether/maleic anhydride copolymer I
AN-1,39, GAF) and 5 parts by weight of polyvinylpyrodone (PVP-90, GAF) were mixed with ethyl alcohol: N,N'-dimethylformamide = 5
: Dissolved in 20 parts by weight of a mixed solvent of 5 and dip coated on the conductive elastic layer of the transfer charging member,
Film thickness after drying], 00 (A 1 m resin layer was provided to produce a roller shape transfer charging member.

This was evaluated in the same manner as in Example 5 and shown in Table 1.

Example 8 A conductive elastic layer of a transfer charging member was prepared in the same manner as in Example 5.

Next, methyl vinyl ether/maleic anhydride copolymer [
AN-149, GAF) and 5 parts by weight of polyvinyl viroson (PVP-890, GAF) were added to 20 M of a mixed solvent of methyl alcohol: MEX: N, N-dimethylformamide = 3:5:2. A roller-shaped transfer charging member was manufactured by dipping the resin layer into a resin layer having a thickness of 10,011 m after drying and coating the conductive elastic layer on the conductive elastic layer of the transfer charging member.

This was evaluated in the same manner as in Example 5 and is shown in Table 2.

Comparative Example 5 A conductive elastic layer of a transfer charging member was prepared in the same manner as in Example 5.

Next is nylon 6-66-10-12. Dissolve 10 parts by weight in 90 parts by weight of methanol and apply by dip coating on the conductive elastic layer of the transfer charging member,
After drying, a resin layer having a thickness of 1100 LL was provided to produce a roller shape transfer charging member.

This was evaluated in the same manner as in Example 5 and is shown in Table 2.

Comparative Example 6 A conductive elastic layer of a transfer charging member was prepared in the same manner as in Example 5.

Next, 10 parts by weight of methoxymethylated nylon 6 (methoxymethylation rate 25%) was dissolved in 90 parts by weight of methanol, and the solution was dip-coated on the conductive elastic layer of the transfer charging member,
After drying, a resin layer having a thickness of 100 μm was provided to produce a roller shape transfer charging member.

This was evaluated in the same manner as in Example 5, and the results are shown in Table 2.

Comparative Example 7 A conductive elastic layer of a transfer charging member was prepared in the same manner as in Example 5.

Next, 8 parts by weight of Tuboran 121 (manufactured by Nippon Polyurethane) and 2 parts by weight of toluylene diisocyanate were dissolved in 90 parts by weight of n-butanol in polyester polyol, and the solution was dip coated onto the conductive elastic layer of the transfer charging member. ,
After drying, a resin layer having a thickness of 100 μm was provided to produce a roller shape transfer charging member.

This was evaluated in the same manner as in Example 5 and is shown in Table 2.

Comparative Example 8 A conductive elastic layer of a transfer charging member was prepared in the same manner as in Example 5.

Next, 10 parts by weight of silicone RTV rubber was dissolved in 90 parts by weight of toluene, and the solution was applied by dip coating onto the conductive elastic layer of the transfer charging member.
After drying, a resin layer having a thickness of 100 μm was provided to produce a roller shape transfer charging member.

This was evaluated in the same manner as in Example 5 and shown in Table 2.

As can be seen from Examples 5, 6, and 7.8 and Comparative Example 5.6, the present invention can maintain high image quality without causing a decrease in density or wavy fog even under low temperature and low humidity conditions.

Furthermore, as can be seen from Examples 5, 6, 7.8 and Comparative Examples 7 and 8, in the present invention, the transfer charging member does not fuse with the photoconductor, nor does it fuse with the toner, so defects may occur in the photoconductor or charging member. Can be used without generation.

Example 9 Below, we investigated its characteristics as a static eliminator.

A photoreceptor was produced in the same manner as in Example 1.

Next, conductive carbon 5 was added to 100 parts by weight of chloroprene rubber.
Melt and knead the weight part and place it on a 2mm x 260mm stainless steel plate with a free length of 10mm x 240mm as shown in Figure 3.
mm, and a conductive elastic layer of a blade-shaped charging member was provided. When the volume resistivity of this static electricity removal charging member is measured in an environment of temperature 22°C and humidity 60%, it is 4 x 10'.
It is Ωcm.

Next, methyl vinyl ether/maleic anhydride copolymer (
AN-139, GAF) 5 parts by weight was added to 1 part of a mixed solvent of ethyl alcohol: NN'-dimethylformamide = 5:5.
0 parts by weight and dip-coated on the conductive elastic layer of the transfer charging member,
A resin layer with a film thickness of 00 μm after drying was formed (C-+), and a blade-shaped static elimination/charging member was manufactured. A resin layer was similarly provided on the aluminum sheet, and the volume resistance was measured.

This neutralizing and charging member was copied using the normal development method llPc-20 (
Attached to the pre-exposure static eliminator (manufactured by Ganon).
For static elimination charging, an AC peak-to-peak voltage of 1.000 V was applied, and the residual potential after static elimination, the image, and the state of the static elimination charging member were examined.

The results are shown in Table 3.

Furthermore, we investigated the volume resistance of the resin layer of the static-eliminating charging member under low-temperature, low-humidity conditions of 15°C and 10% humidity, the image when this static-eliminating charging member was attached to a normal development type copying machine, and the state of the static-eliminating charging member. The results are shown in Table 3.

Example 10 In the same manner as in Example 9, a conductive elastic layer of a static elimination/charging member was prepared.

Next, methyl vinyl ether/maleic anhydride copolymer (
AN-149, GAF) 5 parts by weight of methyl alcohol, MEK:N,N'-dimethylformamide = 3:5:
2 was dissolved in 10 parts by weight of the mixed solvent, and dip coated on the conductive elastic layer of the static elimination/charging member, and after drying, the film thickness was 1OOμ.
A blade-shaped static elimination/charging member was manufactured by providing m resin layers.

This was evaluated in the same manner as in Example 9 and is shown in Table 3.

Example 11 In the same manner as in Example 9, a conductive elastic layer of a static elimination/charging member was prepared.

Next, methyl vinyl ether/maleic anhydride copolymer (
AN-1,39, GAF) 5 parts by weight of polyvinyl virod: / (PVP-90, GAF) 5 parts by weight of ethyl alcohol: N,N'-dimethylformamide = 5:5 mixed solvent 20 weight and dip-coating on the conductive elastic layer of the static elimination charging member,
After drying, a resin layer with a film thickness of 100 μm was provided to produce a blade-shaped static elimination/charging member.

This was evaluated in the same manner as in Example 9 and is shown in Table 3.

Example 12 In the same manner as in Example 9, a conductive elastic layer of a static elimination/charging member was prepared.

Next, methyl vinyl ether/maleic anhydride copolymer (
5 parts by weight of AN-149, GAF) and 5 parts by weight of polyvinylpyrodone (PVP-90, GAF) were mixed with 20 parts by weight of a mixed solvent of methyl alcohol: MEK: N, N''-dimethylformamide = 3:5:2. A blade-shaped static elimination/charging member was manufactured by dipping and coating on the conductive elastic layer of the static elimination/charging member, and after drying, a resin layer having a thickness of 100 μm was provided.

This was evaluated in the same manner as in Example 9 and is shown in Table 3.

Comparative Example 9 In the same manner as in Example 9, a conductive elastic layer of a static elimination/charging member was prepared.

The static elimination/charging member was used as it was without providing a resin layer.

This was evaluated in the same manner as in Example 9 and is shown in Table 3.

Comparative Example 1O In the same manner as in Example 9, a conductive elastic layer of a static elimination/charging member was prepared.

Next, 10 parts by weight of methoxymethylated nylon-6 was dissolved in 90 parts by weight of methanol, and the solution was dip-coated on the conductive elastic layer of the static elimination charging member,
After drying, a resin layer with a film thickness of 100 μm was provided to produce a blade-shaped static elimination/charging member.

This was evaluated in the same manner as in Example 9 and is shown in Table 3.

Comparative Example 11 In the same manner as in Example 9, a conductive elastic layer of a static elimination/charging member was prepared.

Next, 8 parts by weight of Tuboran 121 (manufactured by Nippon Polyurethane) and 2 parts by weight of toluylene diisocyanate were dissolved in 90 parts by weight of n-butanol in polyester polyol, and the solution was dip-coated on the conductive elastic layer of the static elimination charging member. ,
After drying, a resin layer with a film thickness of 100 μm was provided to produce a blade-shaped static elimination/charging member.

This was evaluated in the same manner as in Example 9 and is shown in Table 3.

Comparative Example 12 Static electricity was removed by pre-exposure without using the charging member for charge removal of the present invention, and this was evaluated in the same manner as in Example 9, and the results are shown in Table 3.

As can be seen by comparing Examples 9, 10, 11.12 and Comparative Examples 9 and 11, the present invention prevents fusion between the charging member and the photoreceptor and prevents the occurrence of image defects in the form of horizontal stripes. .

Moreover, as can be seen by comparing Examples 9, 10, 11.12 and Comparative Example 10, stable static elimination performance was exhibited even under low temperature and low humidity, and the material of the present invention can suppress image defects.

In Comparative Example 12, the static elimination performance of the conventional pre-exposure type static elimination is low, and residual potential tends to remain at low temperatures and low humidity (and causes ground burr defects).

[Effects of the Invention] As is clear from the above results, by using the charging member of the present invention, the adhesion to the electrophotographic photoreceptor is low;
Since it is also flexible, it produces high-quality images and produces less toner stains. In particular, stable potential characteristics and image characteristics can be obtained even under low temperature and low humidity conditions.

[Brief explanation of drawings]

Figures 1 and 2 are sectional views in the central axis direction of a roller-shaped charging member, Figure 3 is a sectional view of a blade-shaped charging member, and Figures 4, 5, and 6 are cross-sectional views of an electrophotographic device. It is a diagram. 1a: conductive support, 1b = conductive sheet metal, 2: conductive elastic layer, 3 resin layer, 4: protective layer,
5: resin powder, 6: charging member, 7: image exposure means, 8: developing means, 9: corona charger for transfer charging, 1 discharge cleaning means, 11: pre-exposure means, 12. electrophotographic exposure body, 14; corona charger for secondary charging, 15: charging member for transfer charging, 16: charging member for static elimination charging. Agent Patent Attorney Sekihei Yamashita

Claims (4)

[Claims] (1) A charging member having a conductive elastic layer on a conductive support, characterized in that a resin layer containing a copolymer of alkyl vinyl ether and maleic anhydride is provided on the conductive elastic layer. Parts for use. (2) The charging member according to claim 1, wherein the charging member contacts an electrophotographic photoreceptor to charge the photoreceptor. (3) The charging member according to claim 1, wherein the electrophotographic photoreceptor is primarily charged by superimposing a DC voltage and an AC voltage as applied voltages. (4) The charging member according to claim 1, wherein the developer is transferred from the electrophotographic photoreceptor to the transfer member by using a DC voltage as the applied voltage or by superimposing a DC voltage and an AC voltage. (5) The charging member according to claim 1, wherein the electrophotographic photoreceptor is neutralized using an alternating current voltage as the applied voltage.