JPH0477766A - Electrifying member - Google Patents

Abstract

PURPOSE:To provide the electrifying member which can stably supply 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 hydroxystyrene resin 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 hydroxystyrene resin on the elastic layer 2. The electrifying member having the resin layer contg. the hydroxystyrene resin in such a manner 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. The film thickness of the resin layer is preferably in a 5 to 500mum range.

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 N2 change the surface of the photoreceptor, causing image blurring and deterioration, and wire dirt affects image quality, resulting in white spots and black lines in the image. There were some problems such as: 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, direct charging methods have been researched and used in large numbers (Japanese Patent Application Laid-Open Nos. 178267-1982, 104351-1980, 1983-1
0566, JP-A-58-139156, JP-A-58-1.50975, 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.

[Problem 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 have large fluctuations in resistance under low temperature and low humidity conditions, have unstable charging properties, and cannot be used in contact with an organic photoreceptor. The problem was that the resin on the surfaces of the charging member and the charging member became compatible and stuck together.

Therefore, it is an object of the present invention to provide a charging method that can solve the above-mentioned drawbacks and stably provide high-quality images without spotting caused by non-uniform charging or image defects caused by discharge dielectric breakdown of the photoreceptor. The objective is to provide members for use in the field.

[Means for Solving the Problems] That is, the present invention provides a charging member having a conductive elastic layer on a conductive support, including a resin layer containing a hydroxystyrene resin on the conductive elastic layer. This is a characteristic charging member.

The present invention will be explained in more detail below.

In the charging member of the present invention, as shown in FIG. 1, a conductive elastic layer 2 is provided on a conductive support la, and a resin layer 3 containing hydroxystyrene resin is further provided on the elastic layer 2. The basic structure is a three-layer structure.

The preferred molecular weight of the hydroxystyrene resin is determined by its coating strength and coating properties. In other words, if the molecular weight is extremely low, the strength of the coating will be low and it will be brittle and easily scraped.On the other hand, if the molecular weight is extremely high, the coating viscosity will be high.
The molecular weight is preferably in the range of 3,000 to 1.00,000 since problems such as uneven film thickness and stringiness occur.

Furthermore, a binder resin may be added to the resin layer.

However, the amount of binder resin added is preferably 30% by weight or less based on the total resin. Examples of the binder resin in the resin layer include acrylic resins such as polymethyl methacrylate and polybutyl methacrylate, polyvinyl butyral, polyvinyl acecool, polyarylate, polycarbonate, 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.

, :: h c,: On the other hand, the charging member having a resin layer containing the hydroxystyrene resin of the present invention has low adhesion to the electrophotographic photoreceptor and is flexible, so it can provide high-quality images. , there is little toner staining, and there is little variation in the volume resistivity of the resin layer even under low temperature and low humidity conditions, so it can be used as a stable charging member.

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

The elastic layer 2 can be made of metals such as aluminum, iron, copper, etc., conductive polymers such as polyacetylene, polypyrrole, polythiophene, etc., or rubber or plastic elastomer treated to be conductive with a dispersion of carbon, metal, etc., or the surface of rubber or plastic elastomer. It is possible to use a material coated with a laminate of metal or other conductive material. 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 in order to control the internal conductivity and the surface roughness of the conductive particles and 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 is further provided.

Further, a protective layer may be provided.

The charging member may have any shape such as a roller shape or a plate 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 blank, 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 is casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer polyamide,
It can be formed from polyurethane, gelatin, aluminum oxide, etc. 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 organic photoconductor, tetraelectric material, amorphous silicon, selenium, etc. together with a binder if necessary, or by vacuum deposition. Furthermore, when using a 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 is 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 dispersed with a binder (or without a binder) and formed by coating.

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, polyvinylene helix, polyvinylpyrene, and the like.

The thickness of the charge generation layer is 0.01 to 15 μm, preferably 0.01 to 15 μm.
．． 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, and examples of organic solvents include alcohols, sulfoxides, ethers, esters, and aliphatic halogenated solvents. Hydrocarbons or aromatic compounds can be used.

Coating can be performed using a coating method such as a dip coating method, a spray coach ink method, a Meyer bar coating method, or a plate coating method.

The charge transport layer is formed by dissolving a charge transport material in a film-forming resin. Examples of the organic charge transport materials used in the present invention include hydradun-based compounds, stilhen-based compounds, pyrazoline-based compounds, oxaduran-based compounds,
Examples include thiazur compounds and triarylnokune 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, and phenol. resin, epoxy resin, polyester, alkyd resin, polycarbonate,
Polyurethanes or copolymers containing two or more repeating units of these resins, such as styrene-fukudiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, etc., can be mentioned. 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.
μm, and the weight ratio of charge transport material and binder is 5:1
The ratio is about 1:5 to 1:5, preferably about 3:1 to 13. 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 be less than Ω.

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 in the range of -i from 0.05 to 20 μm. 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. In this apparatus, a primary charging member 6, an image exposure means 7, a developing means 8, a corona charger 9 for transfer charging, a cleaning means 10, and a pre-exposure means 11 are arranged on the circumferential surface of an electrophotographic photoreceptor 12. .

The primary charging member 6 placed in contact with the electrophotographic photoreceptor 12 is applied with an external voltage (for example, 200 μm or more
A pulsating current voltage (which is a superimposition of a DC voltage of V or less and an AC voltage of a peak-to-peak voltage of 4000 V or less) is applied to the electrophotographic photoreceptor 1.
2, the surface of the document is charged, and the image on the document is image-exposed onto the photoreceptor by the image exposure means 7 to form 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.

Images can be formed by such an electrophotographic process, but if residual charges remain on the photoreceptor, the photoreceptor is exposed to light by the pre-exposure means 11 to remove the residual charges before primary charging. It is better to eliminate static electricity.

When using the charging member of the present invention for transfer charging, for example,
It can be applied to 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 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 12. 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 electricity removal charging, for example,
It can be applied to 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 2g9 for transfer charging, and a cleaning means 10 are arranged on the circumferential surface of an electrophotographic photoreceptor 12.

A charging unit for static elimination charging disposed in contact with the electrophotographic photoreceptor 12 (16th voltage (for example, AC peak-to-peak voltage 500
~2000V) can be applied to eliminate the charge on the electrophotographic photoreceptor.

The charging member of the present invention exhibits its characteristics significantly when used in electrophotographic photoreceptors having a photosensitive layer containing an organic photoconductor, which easily deteriorates in terms of mechanical strength and chemical stability. 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 gradually reduced, or in the case of applying a superimposed alternating current on a direct current, a method in which the voltage is applied in the order of direct current (direct current - or 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 electronic electrophotographic applications as a receiving means for receiving image information from laser printers, CRT printers, electrophotographic plate making systems, and remote terminals.

〔Example〕

The present invention will be explained below using examples.

Example 1 As a conductive support, 6oφ×260 with a wall thickness of 0.5mm
A mm aluminum cylinder was prepared.

Copolymerized nylon (product name: CMBOOO1 manufactured by Toshi ■) 4
Part and Type 8 Nai Convex (Product Name: Niratsukamite 50)
03, Dainippon Ink & 1) 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 (trade name: S-LEC B)
10 parts of M2 (manufactured by Building Block Chemical), 12 parts of cyclohexanone
The mixture was dispersed for 10 hours in a Zandmill apparatus with 0 parts. 230 parts of Methyl Ethyl Ke I was added to the dispersion and coated on the undercoat layer to form a charge generation layer with a thickness of 0.15 μm.

10 parts of polycarbonate +-2 resin (manufactured by Mitsubishi Gas Chemical Co., Ltd.) having a weight average molecular weight of 120,000 was prepared and dissolved in 80 parts of monochlorobenzene along with 10 parts of a hydradun compound 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 to form an electrophotographic photoreceptor N.

1 was manufactured.

Next, conductive carbon 5 was added to 100 parts by weight of chloroprene rubber.
Melt and knead the weight part and form φ8X in the center as a conductive support.
φ20X240mm through 260vn stainless steel shaft
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 °C and 60% humidity, it is 3 x 10'Ωcm.

Next, 10 parts by weight of P-hydroxystyrene resin (trade name: Maruzen Resin-M, manufactured by Maruzen Oil Co., Ltd.) was added to 20 parts by weight of ethyl acetate.
The resin was dissolved in parts by weight and applied by dip coating on the conductive elastic layer of the charging member, and after drying, a resin layer having a thickness of 200 μm was provided to produce a roller-shaped charging member.

This charging member is connected to a normal development type copying machine PC as shown in Fig. 3.
-20 (manufactured by Ganon) - Installed in place of the next corona charger, rotated as a result of the electrophotographic photoreceptor, - charged voltage is DC voltage -750cm and AC peak-to-peak voltage 1500V superimposed for 6 seconds, electrophotographic Potential measurements and images of the dark potential and bright potential of the photoreceptor were examined.

The results are shown in Table 1.

Furthermore, the potential characteristics and images when the charging member was placed in a normal development type copying machine under a low temperature and low humidity condition of 15° C. and 10% humidity were examined in the same manner and are shown in Table I.

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

Next, the 7-fold leg part of P-hydroxystyrene resin (Ma/L/Cenresin-M, manufactured by Maruzen Oil Co., Ltd.) and the 3-fold leg part of Me'f-J methacrylate resin (molecular weight Mw = 1.5 x 10') were added to 15% of ethyl acetate. and 5 parts by weight of monochlorobenzene, and dip-coated on the conductive elastic layer of the charging member, and after drying, a cedar oil 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 1 A conductive elastic layer of a charging member was prepared in the same manner as in Example 1.

Next, 5 parts by weight of 6-66-10-12 nylon was dissolved in 90 parts by weight of methanol, and the solution was dip-coated on the conductive elastic layer of the charging member to form a resin layer with a thickness of 200 μm after drying. A roller-shaped charging member was manufactured.

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, methoxymethylated nylon 6 (methoxymethylation rate 25%) 5-fold leg was dissolved in 90 parts by weight of methanol,
A resin layer having a thickness of 200 μm after drying was provided by dip coating on the conductive elastic layer of the charging member 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: Ni-Noboran 1)
21, manufactured by Nippon Polyurethane ■) and 1 part by weight of tolylene 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, and after drying, the film thickness was 200 μm. 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, 5 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 charging member, and after drying, a resin layer with a film thickness of 200 μm was provided, and a roller-shaped charging member was manufactured.

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

As can be seen by comparing 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 temperatures and low humidity.

Further, as can be seen by comparing Example 1.2 and 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.

Example 3 Below, the characteristics as a transfer charger were investigated.

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.
The weight parts were melt-kneaded, passed through a stainless steel shaft of 13 mm x 260 mm in the center, and molded to a size of 30 mm x 240 mm, and a conductive elastic layer of a roller-shaped transfer charging member was provided.

The volume resistance of this transfer charging member is determined by temperature: 22°C, humidity: 6
When measured in a 0% environment, it is 4 x 10'Ωcm.

Next, 10 parts by weight of P-hydroxystyrene (Maruzen Resin M, manufactured by Maruzen Oil Co., Ltd.) was dissolved in 40 parts by weight of ethyl acetate.
dip coating 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 transfer charging member was placed in a normal development type copying machine under a low temperature and low humidity condition of 15° C. and humidity of 10%, and the image and the state of the transfer charging member at the time of one digit were examined and shown in Table 2.

Example 4 In the same manner as in Example 3, a conductive elastic layer of a transfer charging member was prepared.

Next, 7 parts by weight of P-hydroxystyrene (Maruzen Resin M, manufactured by Maruzen Sekiyu) and 3 parts by weight of methyl methacrylate resin (molecular weight axis -1,5X], o5) were dissolved in 30 parts of ethyl acetate and 10 parts by weight of monochlorohengaff. A roller-shaped transfer charging member was then manufactured by dip coating on the conductive elastic outer layer of the transfer charging member and providing a resin layer with a thickness of 10 μm after drying.

This was evaluated in the same manner as in Example 3 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 3.

Next, 5 parts by weight of 6-66-10-12 nylon was dissolved in 90 parts by weight of methanol, and the solution was dip coated onto the conductive elastic layer of the transfer charging member, and after drying, a resin layer with a thickness of 100 μm was provided. , a roller shape transfer charging member was manufactured.

This was evaluated in the same manner as in Example 3 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 3.

Next, 5 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 transfer charging member, and after drying, the film thickness was 100 μm. A roller shape transfer charging member was manufactured by providing a resin layer of.

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

Next, 4 parts by weight of Tuboran 121 (manufactured by Roki Polyurethane) and 1 part by weight of tolylene 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-shaped transfer charging member.

This was evaluated in the same manner as in Example 3 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 3.

Next, 5 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 transfer charging member, and after drying, a resin layer with a film thickness of 100 μm was provided, and the roller shape transfer charging was performed. We manufactured parts for this purpose.

This was evaluated in the same manner as in Example 3 and is shown in Table 2.

As can be seen from Examples 3.4 and Comparative Examples 5 and 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 3 and 4 and Comparative Examples 7 and 8, in the present invention, the transfer charging member does not fuse with the photoreceptor, nor does it fuse with the l/ner, so defects do not occur in the photoreceptor or the charging member. It can be used without

Example 5 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 parts by weight, and add 2 n+n+ x 260 in the center.
Free length 10 mm as shown in Figure 3 on a stainless steel plate of mm.
It was molded to have a diameter of 240 mm, and a conductive elastic layer of a blade-shaped charging member was provided. When the volume resistance of this static neutralizing charging member is measured in an environment with a temperature of 22°C and a humidity of 60%, it is 4.
XlO'Ωcm.

Next, 10 parts by weight of P-hydroxystyrene (Maruzen Resin-M, manufactured by Maruzen Oil Co., Ltd.) was dissolved in 40 parts by weight of ethyl acetate, and the solution was dip-coated on the conductive elastic layer of the static elimination charging member, and after drying, the film was coated. A resin layer with a thickness of 100 μm was provided, and a blade-shaped static elimination/charging member was manufactured.

This static eliminator charging member was installed in place of the pre-exposure static eliminator of the normal development type copying machine PC-20 (Canon), and an AC peak-to-peak voltage of 1000 V was applied for static neutralization, and the residual potential after static neutralization, the image, and the static neutralization charge were The condition of the parts used was examined.

The results are shown in Table 3.

Further, the image and the state of the static eliminating charging member when the static eliminating 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 3.

Example 6 In the same manner as in Example 5, a conductive elastic layer of a static elimination/charging member was prepared.

Next, 7 parts by weight of P-hydroxystyrene (Maruzen Resin M, manufactured by Maruzen Oil Co., Ltd.) and 3 parts by weight of methyl methacrylate resin (molecular weight MW = 1.5X1.O''') were added to 3 parts by weight of ethyl acetate.
It was dissolved in 0 parts by weight and 10 parts by weight of monochlorobenzene, dip-coated on the conductive elastic layer of the static elimination charging member, and after drying, a resin layer with a film thickness of 100 μm was provided to produce a plate-shaped static elimination charging member. .

This was evaluated in the same manner as in Example 5 and is shown in Table 3.

Comparative Example 9 In the same manner as in Example 5, a conductive elastic layer of a static elimination/charging member was prepared.

The defrosting and charging member was used as it was without providing a resin layer.

This was evaluated in the same manner as in Example 5 and is shown in Table 3.

Comparative Example 10 In the same manner as in Example 5, a conductive elastic layer of a static elimination/charging member was prepared.

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 second part of the conductive elastic layer of the static elimination/charging member, and after drying, the film was coated. A resin layer with a thickness of 100 μm was provided, and a blade-shaped static elimination/charging member was manufactured.

This was evaluated in the same manner as in Example 5 and is shown in Table 3.

Comparative Example 11 In the same manner as in Example 5, a conductive elastic layer of a static elimination/charging member was prepared.

Next, 8 parts by weight of Tuboran 121 (Japan Polyurethanes) and 2 parts by weight of toluylene diisocyanate (Japan Polyurethane) 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 heavy-duty member. death,
After drying, a resin layer having a film thickness of 11007 z was provided to produce a blade-shaped static elimination/charging member.

This was evaluated in the same manner as in Example 5 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 5, and the results are shown in Table 3.

As can be seen by comparing Examples 5 and 6 with Comparative Examples 9 and 11, the present invention prevents fusion between the charging member and the photoreceptor, thereby preventing the occurrence of image defects in the form of horizontal stripes.

Further, as can be seen by comparing Examples 5 and 6 with Comparative Example 10, stable static elimination performance was exhibited even under low temperature and low humidity conditions, 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 was low, and residual potential was likely to remain at low temperature and low humidity, causing soil burr defects.

〔Effect 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... Preservation JK layer, 5
. . . Resin) body, 6. Charging member, 7. Image exposure means, 8. Developing means, 9. Corona charger for transfer charging, 10. Cleaning means, 11 ... Pre-exposure means, 12 ... Electrophotographic photoreceptor, 14 ... Corona charger for secondary charging, 15 ... Charging member for transfer charging, 1
6... Charging member for static electricity removal charging. Agent Patent Attorney Selected by Yamashita Children 1 Figure 4 Figure 2 Figure 3 = '13

Claims (4)

[Claims] (1) A charging member having a conductive elastic layer on a conductive support, the charging member having a resin layer containing a hydroxystyrene resin on the conductive elastic layer. (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.