JP2807334B2 - Charging member - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a charging member, and more particularly to a charging member used for primary charging, transfer charging, and charge removal in electrophotography.

[Prior art] The charging process in an electrophotographic process using an electrophotographic photoreceptor has been performed by applying a high voltage (DC) to a metal wire.
(5-8 kV) is applied and charging is performed by the corona generated. However, in this method, ozone and NO
There have been problems such as deterioration of the surface of the photoreceptor due to a corona product such as _X, causing image blurring and deterioration, and contamination of the wire affecting image quality, resulting in image white spots and black stripes. On the other hand, the electric current directed to the photoreceptor is 5 to 30
%, Most of which flowed to the shield plate and was inefficient as a charging means.

In order to compensate for these disadvantages, direct charging methods have been studied and many proposals have been made (JP-A-57-178267, JP-A-56-104351, JP-A-58-40566, JP-A-58-40566). -139156, JP-A-58-150975, etc.).
However, in practice, even if the photosensitive member is charged by the above-described contact charging method, uniform charging of each part of the surface of the photosensitive member is not performed, and spot-like charging unevenness occurs. For example, in the reversal phenomenon method, even if a process of light image exposure or less is applied to the photosensitive member in the spot-like uneven charging state, the output image becomes a spot-like black spot image corresponding to the spot-like charging unevenness, and the spot phenomenon in the normal phenomenon method. The image becomes a spot-like white spot image with respect to unevenness, and a high-quality image cannot be obtained.

Further, the direct charging method has no market record in spite of many proposals. The reasons for this include the uniformity of charging and the occurrence of discharge breakdown of the photoreceptor due to direct application of a voltage. One breakdown point due to discharge breakdown, for example, in the case of a cylindrical photosensitive member, has a drawback that charging in the entire axial direction flows to the breakdown point and the charge is no longer charged.

[Problems to be Solved by the Invention] A method of forming a resin layer on the surface in order to prevent the dielectric breakdown has also been reported (JP-A-1-205180, JP-A1-211779).

However, these materials also have large fluctuations in resistance at low temperatures and low humidity, and have unstable charging properties. When used in contact with an organic photoconductor, the organic photoconductor and the resin on the surface of the charging member are incompatible with each other. It had defects such as melting and sticking.

Accordingly, an object of the present invention is to solve the above-mentioned drawbacks and to provide a spot-like fog due to non-uniform charging, and to stably supply a high-quality image free from image defects and the like due to discharge breakdown of a photoconductor. It is to provide a member.

[Means for Solving the Problems] That is, the present invention relates to a charging member having a conductive elastic layer on a conductive support, wherein polybutylene glycol, polypentene glycol, polyhexene glycol, A charging member characterized by having a resin layer containing a polyalkylene glycol selected from the group consisting of polyheptene glycol, polyoctene glycol and polydecanediol.

 Hereinafter, the present invention will be described in more detail.

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

As the polyalkylene glycol in the present invention,
Polybutylene glycol, polypentene glycol, polyhexene glycol, polyheptene glycol, polyoctene glycol, polydecanediol can be used. The structure of the alkyl group may be a straight-chain structure or a branched structure.

Next, specific examples of the polyalkylene glycol are shown by a structural formula.

_{HO- [(CH 2) 4 O} ] n -H (1) HO- [(CH 2) 5 O] n -H (2) HO- [(CH 2) 6 O] n -H (3) (n : Integer) Further, a binder resin may be added to the resin layer.
However, the addition amount of the binder resin is preferably 80% 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 acetal, polyarylate, polycarbonate, phenoxy resin, polyvinyl acetate, and polyvinyl pyridine.

Since the conventional charging member has a surface made of rubber or polyurethane, if the electrophotographic photoreceptor is kept in contact, the photoreceptor and the charging member are fixed, or a hard surface is wrinkled, Image defects occurred.

On the other hand, the charging member having the resin layer containing the polyalkylene glycol of the present invention has low adhesion to the electrophotographic photoreceptor, and has high flexibility, so that a high-quality image is provided, and toner smear is reduced. Even under low temperature and low humidity, the volume resistance of the resin layer does not fluctuate much and can be used as a stable charging member.

The thickness of the resin layer is preferably in the range of 5 to 500 μm, particularly preferably in the range of 20 to 200 μm.

Metal such as aluminum, iron, and copper as the elastic layer 2;
Conductive polymers such as polyacetylene, polypyrrole, and polythiophene, and rubber and plastic elastomers that have been treated by dispersing carbon, metal, etc., and those obtained by laminating the surface of rubber or plastic elastomer with a metal or other conductive material, etc. Can be used. Further, the elastic layer 2 may have a multilayer structure in which functions are separated as necessary. Iron, copper, stainless steel, or the like can be used as the conductive support 1a.

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 may be mixed with conductive particles for controlling the internal conductivity or insoluble resin powder 5 for controlling 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 a conductive sheet metal 1b, and a resin layer 3
Is provided.

 Further, a protective layer may be provided.

The shape of the charging member may be any of a roller shape and a blade shape, but is preferably a roller shape in terms of uniform charging.

The electrophotographic photoreceptor is based on a configuration in which a photosensitive layer is provided on a conductive support. As the conductive support, a support having conductivity itself, for example, aluminum, an aluminum alloy, stainless steel, chromium, titanium, or the like can be used.In addition, aluminum, an aluminum alloy, an indium oxide-tin oxide alloy, or the like can be used. A conductive support having a layer formed by vacuum deposition, plastic, a support in which conductive particles (eg, carbon black, tin oxide particles, etc.) are impregnated with a suitable binder into plastic or paper, and a conductive binder. Plastic or the like can be used.

An undercoat layer having a barrier function and an adhesive function may be provided between the conductive support and the photosensitive layer. The undercoat layer can be formed of casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, polyamide, polyurethane, gelatin, aluminum oxide, or the like. The thickness of the undercoat layer is 5 μm or less, preferably 0.5 to 3 μm.
μm is appropriate. The undercoat layer preferably has a resistivity of 10 ⁷ Ω · cm or more in order to exhibit its function.

The photosensitive layer is formed, for example, by coating a photoconductor such as an organic photoconductor, amorphous silicon, or selenium with a binder as necessary, and forming the coating by coating or vacuum deposition. When an organic photoconductor is used, a photosensitive layer composed of a combination of a charge generation layer that generates charge carriers upon exposure and a charge transport layer capable of transporting the generated charge carriers can also be used effectively.

The charge generation layer is formed by depositing one or more kinds of charge generation materials such as azo pigments, quinone pigments, quinocyanine pigments, perylene pigments, indigo pigments, bisbenzimidazole pigments, phthalocyanine pigments, quinacdrine pigments, or an appropriate one. It can be formed by dispersing together with a binder (even without a binder) and coating.

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

The thickness of the charge generation layer is 0.01 to 15 μm, preferably 0.05 to
5 μm, and the weight ratio between the charge generation layer and the binder is 10: 1 to
1:20.

The solvent used for the coating for the charge generation layer is selected from the solubility and dispersion stability of the resin and the charge transporting material used. As the organic solvent, alcohols, sulfoxides, ethers, esters, and aliphatic halides are used. Hydrocarbons or aromatic compounds can be used.

The coating can be performed using a coating method such as an immersion coating method, a spray coating method, a Meyer bar coating method, and a blade coating method.

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

Examples of the resin used for the charge transport layer include phenoxy resin, polyacrylamide, polyvinyl butyrate, polyarylate, polysulfone, polyamide, acrylic resin, acrylonitrile resin, methacryl resin, vinyl chloride resin, vinyl acetate resin, phenol resin, and epoxy resin. , Polyester, alkyd resin, polycarbonate,
Polyurethanes or copolymers containing two or more of the repeating units of these resins, such as styrene-butadiene copolymers, styrene-acrylonitrile copolymers,
Styrene-maleic acid copolymer and the like can be mentioned. It can also be selected from organic photoconductive polymers such as poly-N-vinyl carbazole, polyvinyl anthracene, polyvinyl pyrene.

The thickness of the charge transport layer is 5 to 50 μm, preferably 8 to 20 μm.
m, and the weight ratio of the charge transport material to the binder is 5: 1 to 1:
5, preferably about 3: 1 to 1: 3. The coating can be performed by the coating method described above.

Furthermore, since dyes, pigments, organic charge transporting substances, and the like are generally vulnerable to contamination by ultraviolet rays, ozone, oil, and the like, metals, and the like, a protective layer may be provided as necessary. To form an electrostatic latent image on this protective layer, the surface resistivity must be 10 ¹¹ Ω
It is desirable that this is the case.

The protective layer of the photoconductor is made of a resin such as polyvinyl butyral, polyester, polycarbonate, acrylic resin, methacrylic resin, nylon, polyimide, polyarylate, polyurethane, styrene-butadiene copolymer, styrene-acrylic acid copolymer, styrene-acrylonitrile copolymer. A solution dissolved by a solvent can be formed by applying and drying the photosensitive layer on the photosensitive layer. At this time, the thickness of the protective layer is generally in the range of 0.05 to 20 μm. The 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 unit 7, a developing unit 8, a corona charging base 9 for transfer charging, a cleaning unit 10, and a pre-exposure unit 11 are arranged on a peripheral surface of an electrophotographic photosensitive member 12. .

A voltage (for example, a pulsating voltage in which a DC voltage of 200 V or more and 2000 V or less and an AC voltage of 4000 V or less between peaks are superimposed) is externally applied to the primary charging member 6 which is arranged in contact with the electrophotographic photosensitive member 12. Then, the surface of the electrophotographic photosensitive member 12 is charged, and the image on the original is image-exposed to the photosensitive member by the image exposure means 7 to form an electrostatic latent image. Next, the electrostatic latent image on the photoconductor is developed (visualized) by adhering the developer in the developing means 8 to the photoconductor, and the developer on the photoconductor is transferred to a corona charger for charging. By 9, the developer is transferred to a transfer member 13 such as paper, and the developer remaining on the photoconductor without being transferred to the paper at the time of transfer by the cleaning unit 10 is collected.

An image can be formed by such an electrophotographic process, but if residual charges remain on the photoconductor, light is applied to the photoconductor by the pre-exposure means 11 before primary charging to remove the residual charges. You had better.

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. This apparatus includes a primary charging corona charger 14, an image exposure means 7, a developing means 8, a transfer charging member 15, a cleaning means 10, a pre-exposure means
11 are located.

A voltage (for example, a DC voltage of 400 to 1000 V) is applied to the transfer charging member 15 which is arranged in contact with the electrophotographic photosensitive member 12 to transfer the developer on the electrophotographic photosensitive member to a transfer member such as paper. Can be.

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 primary charging corona charger 14, an image exposure unit 7, a developing unit 8, a transfer charging corona charger 9, and a cleaning unit 10 are arranged on a peripheral surface of an electrophotographic photosensitive member 12.

A voltage (for example, an AC peak-to-peak voltage of 500 to 2000)
V) can be applied to eliminate charges on the electrophotographic photosensitive member.

The charging member of the present invention exerts its characteristics remarkably by being applied to an electrophotographic photosensitive member having a photosensitive layer containing an organic photoconductor, which is susceptible to deterioration in mechanical strength and chemical stability. can do.

The installation of the charging member to be brought into contact with the photoreceptor in the present invention is not limited to a specific method. it can. Further, it is also possible for the charging member to function as a developer cleaning device on the photosensitive member.

Voltage applied to the charging member in the DC charging of the present invention,
Regarding the application method, it depends on the specifications of each electrophotographic apparatus, but in addition to the method of applying the desired voltage instantaneously, the method of gradually increasing the applied voltage for the purpose of protecting the photoreceptor, the method of applying DC to AC Can be applied in the order of DC AC or AC DC in the case of superimposing.

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

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

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 AC voltage.

In the present invention, processes such as image exposure, development, and cleaning can employ any method known in the field of electrostatography, and are not limited to a specific type such as a type of developer. The charging member of the present invention can be used not only for copying machines but also for electrophotographic applications such as laser printers, CRT printers, and electrophotographic plate making systems.

EXAMPLES Hereinafter, the present invention will be described with reference to Examples.

Example 1 An aluminum cylinder having a thickness of 0.5 mm and a diameter of 60 mm × 260 mm was prepared as a conductive support.

Copolymer nylon (trade name: CM8000, manufactured by Toray Industries, Inc.) 4
Part and type 8 nylon (Product name: Ratsukamide 500
3, Dainippon Ink Co., Ltd.) 4 parts methanol 50 parts, n
-Dissolved in 50 parts of butanol and dip-coated on the support to form a 0.6 μm thick undercoat layer.

10 parts of disazo pigment of the following structural formula, And polyvinyl butyral resin (trade name: Eslek BM
2, Sekisui Chemical Co., Ltd.) and 10 parts of cyclohexanone were dispersed in a sand mill for 10 hours. Add 30 parts of methyl ethyl ketone to the dispersion and apply on the undercoat layer,
A charge generation layer having a thickness of 0.15 μm was formed.

Then, 10 parts of a polycarbonate Z resin having a weight average molecular weight of 120,000 (manufactured by Mitsubishi Gas Chemical Co., Ltd.) is prepared, and a hydrazone compound having the following structural formula is prepared. It was dissolved in 80 parts of monochlorobenzene together with 10 parts. This was applied on the charge generation layer to form a charge transport layer having a thickness of 16 μm, thereby producing an electrophotographic photosensitive member No. 1.

Next, conductive carbon 5 was added to 100 parts by weight of chloroprene rubber.
Melt and knead parts by weight, φ8 ×
It was formed into a diameter of 20 × 240 mm through a stainless steel shaft of 260 mm, and a conductive elastic layer of a roller-shaped charging member was provided.

The volume resistance of the conductive elastic layer of the charging member is set to 22
It is 3 × 10 ⁴ Ωcm when measured in an environment of 60 ° C. and 60% humidity.

Next, 10 parts by weight of polybutylene glycol (Structural Formula 1) is dissolved in 90 parts by weight of ethanol, dip-coated on the conductive elastic layer of the charging member, and dried to form a 200 μm-thick resin layer. A roller-shaped charging member was manufactured. A resin layer was similarly provided on the aluminum sheet, and the volume resistance was measured.

As shown in FIG. 3, this charging member is used as a positive development type copying machine PC.
-20 (manufactured by Canon) In place of the primary corona charger, it is driven to rotate with the electrophotographic photoreceptor, and the primary charging voltage is a superposition of a DC voltage of -750 V and an AC peak-to-peak voltage of 1500 V. The dark potential of the electrophotographic photoreceptor The potential measurement of bright potential and the image were examined.

 The results are shown in Table 1.

Furthermore, the volume resistance of the resin layer of the charging member, the potential characteristics when the charging member was attached to the positive development type copying machine, and the image in a low-temperature and low-humidity state of a temperature of 15 ° C. and a humidity of 10% were similarly examined. showed that.

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

Next, 15 parts by weight of polypentene glycol (Structural formula 2) is dissolved in 85 parts by weight of propanol, dip-coated on the conductive elastic layer of the charging member, and dried to form a 200 μm-thick resin layer. A roller-shaped charging member was manufactured.

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

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

Next, 10 parts by weight of nylon 6-66-10-12 methanol 90
It was dissolved in parts by weight, and was applied by dip coating on the conductive elastic layer of the charging member. After drying, a resin layer having 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 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 (methoxylation rate 25%)
Dissolve 10 parts by weight in 90 parts by weight of methanol, apply dip coating on the conductive elastic layer of the charging member, and dry to a thickness of 200 μm.
m, and a roller-shaped charging member was manufactured.

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

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

Next, 8 parts by weight of a polyester polyol (Nipporan 121, manufactured by Nippon Polyurethane Co., Ltd.) and 2 parts by weight of toluylene diisocyanate are dissolved in 90 parts by weight of n-butanol, and then dip-coated on the conductive elastic layer of the charging member. Work,
After drying, a resin layer having a 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 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 silicon RTV rubber was dissolved in 90 parts by weight of toluene, and the solution was 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. Was manufactured.

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

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

Further, as can be seen by comparing Examples 1 and 2 with Comparative Examples 3 and 4, it is possible to prevent fusion between the charging member and the photosensitive member and suppress the occurrence of a horizontal streak image.

Although the polyurethane resin layer has a high volume resistance as in Comparative Example 3, the inclusion of polyalkylene glycol as in Examples 1 and 2 results in a lower volume resistance than the respective materials and a more useful charging characteristic. Is shown.

Example 3 Hereinafter, characteristics as a transfer charger were examined.

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

Next, conductive carbon 5 was added to 100 parts by weight of chloroprene rubber.
A part by weight was melted and kneaded, and formed into a φ30 × 240 mm through a stainless shaft of φ8 × 260 mm at the center to provide a conductive elastic layer of a roller-shaped transfer charging member.

The volume resistance of the transfer charging member is set to a temperature of 22 ° C and a humidity of 60%.
It is 4 × 10 ⁴ Ωcm when measured in the environment.

Next, 10 parts by weight of polybutylene glycol (Structural Formula 1) is dissolved in 90 parts by weight of ethanol, dip-coated on the conductive elastic layer of the transfer charging member, and dried to a thickness of 100 μm.
To form a roller-shaped transfer charging member. A resin layer was similarly provided on the aluminum sheet, and the volume resistance was measured.

This transfer charging member was attached in place of the transfer corona charger of the positive development type copying machine PC-20 (manufactured by Canon), and DC-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 volume resistance of the resin layer of the transfer charging member in a low temperature and low humidity state of a temperature of 15 ° C. and a humidity of 10%, and the state of the image and the state of the transfer charging member when the transfer charging member is attached to a positive development type copying machine. The results are 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, 10 parts by weight of polypentene glycol (the above structural formula 2) is dissolved in 90 parts by weight of ethanol, dip-coated on the conductive elastic layer of the transfer charging member, and dried to a thickness of 100 μm.
And a roller-shaped charging member was manufactured.

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

Comparative Example 5 In the same manner as in Example 3, a conductive elastic layer of a transfer charging member was prepared.

Next, 10 parts by weight of nylon 6-66-10-12
The resin was dissolved in 90 parts by weight, and was applied by dip coating on the conductive elastic layer of the transfer charging member. After drying, a resin layer having a film 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 6 In the same manner as in Example 3, a conductive elastic layer of a transfer charging member was prepared.

Next, methoxymethylated nylon (methoxylation rate 25%)
Dissolve 10 parts by weight in 90 parts by weight of methanol, dip-coat on the conductive elastic layer of the transfer charging member, and dry to a film thickness of 10 parts.
A 0 μm resin layer 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 7 In the same manner as in Example 3, a conductive elastic layer of a transfer charging member was prepared.

Next, 8 parts by weight of a polyester polyol (Nipporan 121, manufactured by Nippon Polyurethane) and 2 parts by weight of toluylene diisocyanate are dissolved in 90 parts by weight of n-butanol, 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-shaped transfer charging member.

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

Comparative Example 8 In the same manner as in Example 3, a conductive elastic layer of a transfer charging member was prepared.

Next, 10 parts by weight of silicon RTV rubber was dissolved in 90 parts by weight of toluene, and the resultant was applied by dip coating on the conductive elastic layer of the transfer charging member, and after drying, a resin layer having a thickness of 100 μm was provided. The members for manufacture were manufactured.

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

As can be seen from Examples 3 and 4 and Comparative Examples 5 and 6, in the present invention, even under low temperature and low humidity, high image quality can be maintained without lowering of density or wavy capri.

Further, 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 photoconductor and also does not fuse with the toner, so that no defect occurs in the photoconductor and the charging member. Can be used.

Example 5 Hereinafter, characteristics as a static eliminator were examined.

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

Next, conductive carbon 5 was added to 100 parts by weight of chloroprene rubber.
A part by weight was melt-kneaded and molded on a 2 mm × 260 mm stainless plate at the center so as to have a free length of 10 mm × 240 mm as shown in FIG. 3 to provide a conductive elastic layer of a blade-shaped charging member. The volume resistance of the charge removing member is set to a temperature of 22 ° C and a humidity of 60.
It is 4 × 10 ⁴ Ωcm when measured in a% environment.

Next, 10 parts by weight of polybutylene glycol (Structural formula 1) is dissolved in 90 parts by weight of ethanol, dip-coated on the conductive elastic layer of the charge removing member, and dried to a thickness of 100 μm.
To form a blade-shaped member for static elimination and charging. A resin layer was similarly provided on the aluminum sheet, and the volume resistance was measured.

This static elimination charging member is installed in place of the pre-exposure static eliminator of the positive development type copier PC-20 (manufactured by Canon). For static elimination, an AC peak-to-peak voltage of 1000 V is applied. The state of the members for use was examined.

 The results are shown in Table 3.

Furthermore, the volume resistance of the resin layer of the charge-eliminating member at a temperature of 15 ° C. and a humidity of 10% in a low-temperature and low-humidity state, and the image and the state of the charge-eliminating member when the charge-eliminating member is attached to the positive development type copying machine are shown. The results are shown in Table 3.

Example 6 In the same manner as in Example 5, a conductive elastic layer of a member for discharging and charging was prepared.

Next, 10 parts by weight of polypentene glycol (Structural Formula 2) was dissolved in 90 parts by weight of isopropanol, dip coated on the conductive elastic layer of the charge removing member, and dried to a film thickness of 10 parts.
A resin layer having a thickness of 0 μm was provided, and a blade-shaped member for static elimination and charging was manufactured.

 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 member for discharging and charging was prepared.

The charge removing member was used 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 member for discharging and charging was prepared.

Next, 10 parts by weight of methoxymethylated nylon-6 (methoxymethylation rate 25%) was dissolved in 90 parts by weight of methanol, dip-coated on the conductive elastic layer of the charge removing member, and dried. A 100 μm resin layer was provided to produce a blade-shaped member for static elimination and charging.

 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 member for discharging and charging was prepared.

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

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

Comparative Example 12 The static elimination was performed by pre-exposure without using the static elimination and charging member of the present invention.

As can be seen from a comparison between Examples 5 and 6 and Comparative Examples 9 and 11, in the present invention, fusion between the charging member and the photoconductor is prevented, and occurrence of horizontal stripe-shaped image defects is prevented.

In addition, as can be seen by comparing Examples 5 and 6 and Comparative Example 10, stable static elimination performance is exhibited even at low temperature and low humidity, and the material of the present invention can suppress image defects.

In Comparative Example 12, the static elimination performance was low in the conventional pre-exposure type static elimination, and the residual potential was likely to remain at low temperature and low humidity, causing other fog 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 photosensitive member is low,
It is flexible and gives high-quality images, and has less toner stains. In particular, stable potential characteristics and image characteristics can be obtained even under low temperature and low humidity.

[Brief description of the drawings]

1 and 2 are cross-sectional views in the direction of the central axis of a roller-shaped charging member, FIG. 3 is a cross-sectional view of a blade-shaped charging member, FIG. 4, FIG. 5, and FIG. FIG. 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: Transfer charging corona charger 10: Cleaning means 11: Pre-exposure means 12: Electrophotographic photoreceptor 13: Transfer receiving member 14: Primary charging corona charger 15: Transfer charging member 16: Static charge member

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Haruka Sakami 3- 30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kumi Tanaka 3- 30-2 Shimomaruko, Ota-ku, Tokyo Canon (56) References JP-A-2-230267 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03G 15/02 101 G03G 15/16 103 G03G 21/00 340

Claims (6)

(57) [Claims] 1. A charging member having a conductive elastic layer on a conductive support, comprising: a polybutylene glycol, a polypentene glycol, a polyhexene glycol, a polyheptene glycol, a polyoctene glycol on the conductive elastic layer. A charging member having a resin layer containing a polyalkylene glycol selected from the group consisting of polydecanediol. 2. The charging member according to claim 1, wherein the polyalkylene glycol is polybutylene glycol or polypentene glycol. 3. The charging member according to claim 1, wherein the charging member contacts the electrophotographic photosensitive member and charges the photosensitive member. 4. The charging member according to claim 3, wherein a DC voltage and an AC voltage are superimposed as an applied voltage to primary charge the electrophotographic photosensitive member. 5. The charging member according to claim 1, wherein a DC voltage is used as the applied voltage, and the DC voltage and the AC voltage are superimposed to transfer the developer from the electrophotographic photosensitive member to the member to be transferred. 6. The charging member according to claim 1, wherein the electrophotographic photosensitive member is neutralized by using an AC voltage as an applied voltage.