JPH0467067A - Electrifying member - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] 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 scratches in the image. There were other problems. On the other hand, in terms of electric power, only 5 to 30% of the current flows to the photoreceptor, and most of it flows 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 Nos. 57-178267, 1982-104351, 1982-4).
0566, JP-A-58-139155, 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 lower than optical image exposure is applied to a photoreceptor with spotty charging unevenness, the output image will have spots and skewered black dots corresponding to the spotty charging unevenness. In the peeping image method, a high-quality image cannot be obtained because a speckled white dot image is produced in contrast to the speckled unevenness.

Further, although there are many proposals for the direct charging method, there is little market experience. Reasons for this include the uniformity of charging and the occurrence of electrical discharge breakdown of the photoreceptor due to direct voltage application. For one breakdown due to discharge breakdown,
For example, in the case of a cylindrical photoreceptor, there was a drawback that the charging in the entire axial direction flows to the breakdown point and 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 this dielectric breakdown has also been reported (Japanese Unexamined Patent Publication No. 1-205180, Japanese Unexamined Patent Application Publication No. 1999-211779).

However, these materials also have large fluctuations in resistance at low temperatures and low humidity, and their charging properties are unstable, and when used in 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, an object of the present invention is to solve the above-mentioned drawbacks and to stably supply high-quality images without the occurrence of spot fog due to uneven charging or image defects due to discharge dielectric breakdown of the photoreceptor. An object of the present invention is to provide a charging member.

[Means for Solving the Problems] That is, the present invention is a charging member having a conductive elastic layer on a conductive support, characterized by having a resin layer containing an alkyd resin on the conductive elastic layer. This is a charging member.

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 a resin layer 3 containing an alkyd resin provided on an elastic layer M2. The basic form is a layered structure.

Alkyd resin is a synthetic resin obtained by the condensation reaction of polyhydric alcohol and polybasic acid, and there are many types depending on the polyhydric alcohol and polybasic acid used as materials, as well as the modifier.

A suitable alkyd resin in the present invention is a fatty acid-modified alkyd resin having oxygen convertibility. This is in the air!
! It has the property of converting into an infusible state by reacting with two elements, and is used as a paint.

Catalysts are used to speed up the reaction with oxygen, but
For example, metal salt catalysts such as octylate, cobalt naphthenate, cobalt, manganese, zirconium, etc. are used.

Specific examples of alkyd resins include alkyd resin modified with castor oil (part name: Betsukosol 13o8, manufactured by Dainippon Ink Chemical Co., Ltd.), alkyd resin modified with linseed oil (product name: Nibetsukosol 1344, manufactured by Dainippon Ink Chemical Co., Ltd., product name: :
Alkyd resins modified with tall oil (trade name, Arachide 1465-60, manufactured by Arakawa Chemical), etc.

Furthermore, a binder resin may be added to the resin layer. However, the amount of binder resin added is 30% by weight based on the total resin.
The following are preferred. 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, polyvinyl pyridine, and the like.

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.

On the other hand, the charging member having a resin layer containing the alkyd resin of the present invention has less adhesion to the electrophotographic photoreceptor and is flexible, so it provides high quality images, has less toner staining, and has low temperature and low humidity. There is little variation in the volume resistivity of the resin layer even under the condition that it can be used as a stable charging member.

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

The volume resistivity of the resin layer is preferably in the range of 10 6 to 10 12 Ω·cm. Further, as shown in Japanese Patent Application No. 62-230334, the volume resistivity of the resin layer is preferably larger than the volume resistivity of the lower conductive elastic layer in contact with the resin layer. The volume resistance of the elastic layer is lO°~1011Ω'cm
In particular, a range of 102 to 1010 Ω'cm is preferred. As the elastic layer 2, metals such as aluminum, iron, copper, etc., conductive polymers such as polyacetylene, polypyrrole, polythiophene, etc., rubber or plastic elastomer treated to be conductive by dispersing carbon, metal, etc., or the surface of rubber or plastic elastomer can be used. A laminate coated with metal or other conductive material 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 conductivity and 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 preferably 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 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, 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, but 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 coating method, a wire bar coating method, or a blade coating method.

The charge transport layer is formed by dissolving a charge transport material in a film-forming resin. Examples of organic charge transport materials that can be 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,
Polyesters, alkyd resins, polycarbonates, polyurethanes, or copolymers containing two or more repeating units of these resins, such as styrene-butadiene copolymers, styrene-acrylonitol copolymers, styrene-maleic acid copolymers, etc. I can do it. 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 um, preferably 8 to 20 um.
The weight ratio of charge transport substance and binding agent is 5:1.
The ratio is approximately 1:5 to 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 must be 10Ω.
The above is desirable.

The protective layer of the photoreceptor is made of polyvinyl butyral, polyester, polycarbonate, acrylic resin, methacrylic resin,
Nylon, polyimide polyarylate, polyurethane,
It can be formed by dissolving a resin such as styrene-butadiene copolymer, styrene-acrylic acid copolymer, or styrene-acrylonitrile copolymer in a suitable organic solvent and coating the photosensitive layer 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 um.

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 i on the circumferential surface of an electrophotographic photoreceptor 12.
7. Developing means 8, Corona charger 9 for transfer charging, Cleaning means 10. A pre-exposure means 11 is arranged.

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 DC voltage of V or less and a peak-to-peak voltage of 400 [pulsating current voltage with AC voltage of IV or less] are applied to charge the surface of the electrophotographic photoreceptor 12, and the image on the document is transferred to the photoreceptor by the image exposure means 7. Image exposure is performed 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. The developer is transferred to a transfer member 13 such as paper by the developer 9, and the developer remaining on the photoreceptor without being transferred to the paper during the transfer is collected by the cleaning hand PR10.

Although an image can be formed by such an electrophotographic process, 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 the next charging. 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. This device includes 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. A pre-exposure means 11 is arranged.

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 primary charging corona charger 14, an image exposure element Pj7, a developing means 8, a transfer charging corona charger 9, 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. It is possible to adopt a method of increasing the applied voltage in stages, or a method of applying voltage in the order of AC (or AC = 6 DC).

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, faxes, electrophotographic plate-making systems, and facsimile machines having a receiving means for receiving image information from a remote terminal. be able to.

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

Example 1 As a conductive support, 60φ×26 with a wall thickness of 0.5n+m
An aluminum cylinder of 0 m+n 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 by dip coating onto the above support to form a 0.6 gm 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 having a thickness of 0.151 parts.

10 parts of polycarbonate Z 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 hydrazone compound having the following structural formula. This was coated on the charge generation layer to form a charge transport layer having 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.
φ20 x 2 through the x 260mm stainless steel shaft
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 3XIO4Ω'cm.

Next, 10 parts by weight of a castor oil-modified alkyd resin (trade name Betsukosol 1308, manufactured by Dainippon Ink Chemical Co., Ltd.) and 1 part by weight of cobalt naphthenate were dissolved in 90 parts by weight of toluene and placed on the conductive elastic layer of the charging member. A roller-shaped charging member was manufactured by dip coating and providing a resin layer with a thickness of 200 um after drying. 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, rotates as a result of the electrophotographic photoreceptor, and the wide charging voltage is obtained by superimposing the DC voltage -750V and the AC inter-plane voltage of 1500V, and the electrophotographic photoreceptor is Potential measurements and images of the body's Bit position and bright potential 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, 10 parts by weight of linseed oil-modified alkyd resin (trade name: Betsukosol 1344, manufactured by Dainippon Ink Chemical) and 1 part by weight of lead octylate were dissolved in 90 parts by weight of xylene to form the conductive elastic layer of the charging member. A roller-shaped charging member was manufactured by dip coating on the resin layer and providing a resin layer with a thickness of 200 um after drying.

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

Comparative Example] 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 was dissolved in 90 parts by weight of methanol, and the solution was dip coated onto the conductive elastic layer of the charging member, and after drying, a resin layer with a thickness of 200 um was provided. , 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 (methoxylation rate 25%)
) 10 parts by weight were dissolved in 90 parts by weight of methanol, and applied by dip coating on the conductive elastic layer of the charging member described in i￥ii above, and after drying, a resin layer with a film thickness of 200 um was provided, and a resin layer was formed to form a molar-shaped charging member. The parts were manufactured.

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 Niraporan 121)
Nippon Polyurethane Co., Ltd.) 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 form a resin layer with a film thickness of 200 ulTl 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 4 A conductive elastic layer of a charging member was prepared in the same manner as in Example 1.

Next, a mixture of 10 parts by weight of silicone RTV rubber and 90 parts by weight of toluene was 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 form a roller-shaped charging member. The parts were manufactured.

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

As can be seen by comparing Example 1.2 and 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.

Further, as can be seen by comparing Example 1.2 and Comparative Example 34, it is possible to prevent fusion between the charging member and the photoreceptor, and to suppress the occurrence of horizontal streak images.

Although the polyurethane resin layer has a high volume resistivity as in Comparative Example 3, the alkyd resin layer as in Example 1.2 has an appropriate volume resistivity and exhibits more useful charging characteristics.

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

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

Next, 5 parts by weight of conductive carbon was melted and kneaded with 100 parts by weight of chloroprene rubber, and the mixture was molded into a diameter of 30 mm by 240 mm through a stainless steel shaft of 8 mm by 260 mm in the center to form the conductive elastic layer of the roller shape transfer charging member. 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, 10 parts by weight of castor oil-modified alkyd resin (trade name: Betsukosol 1308, manufactured by Dainippon Ink Chemical) and 0.1 parts by weight of cobalt naphthenate were dissolved in 90 parts by weight of toluene, and the conductive elasticity of the transfer charging member was dissolved. A resin layer having a thickness of 100 μm after drying was provided on the layer by dip coating to produce a roller shape transfer charging member. A resin layer was similarly provided on the aluminum sheet, and this transfer charging member was attached in place of the transfer corona charger of a normal development type copying machine PC-20 (manufactured by Canon), and a direct current of -500 cm was applied for transfer charging. The condition of the image and transfer charging member was examined.

The results are shown in Table 2.

Furthermore, the temperature is 15℃ and the humidity is 10%. The image and the state of the transfer charging member when the transfer charging member was attached to a normal development type copying machine in the R state were investigated and 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 linseed oil-modified alkyd resin (trade name: Betsukosol 1344, manufactured by Dainippon Ink Chemical) and 0.1 parts by weight of lead octylate were dissolved in 90 parts by weight of xylene to improve the conductivity of the transfer charging member. Dip coating on the elastic layer,
A resin layer having a thickness of 1100 μm after drying was provided to produce a roller shape transfer charging member.

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, nylon 6-66-10-1210 parts by weight was dissolved in 90 parts by weight of methanol and dip-coated on the conductive elastic layer of the transfer charging member,
After drying, a resin layer with a thickness of 1100 u 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, 610 parts by weight of methoxymethylated 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,
A resin layer having a thickness of 1100 μm after drying was provided to produce a roller shape transfer charging member.

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, polyester polyol (product name Niraporan 121)
, manufactured by 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 transfer charging member, and after drying, a film thickness of 1100 LL was obtained. A resin layer was provided to produce a roller shape 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, 10 parts by weight of silicone RTV rubber and 90 parts by weight of toluene.
A roller-shaped transfer charging member was manufactured by dissolving the resin in parts by weight and dip coating on the conductive elastic layer of the transfer charging member to form a resin layer having a thickness of 1100 LL after drying.

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 photoconductor, nor does it fuse with the toner, so no defects occur in the photoconductor or the charging member. Can be used.

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 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.
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, 10 parts by weight of castor oil-modified alkyd resin (trade name: Betsukosol 1308, manufactured by Dainippon Ink Chemical) and 0.1 parts by weight of cobalt naphthenate were dissolved in 90 parts by weight of toluene, and the conductive elasticity of the transfer charging member was dissolved. A resin layer having a thickness of 100 μm was provided on the layer by dip coating, and after drying, 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 charge-eliminating member was installed in place of the pre-exposure charge eliminator of the normal development type copying machine PC-20 (manufactured by Canon), and an AC peak-to-peak voltage of 1000 V was applied for charge removal, and the residual potential after charge removal, the image, and the charge removal charge were applied. The condition of the parts used was 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 6 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 linseed oil-modified alkyd resin (trade name: Betsukosol 1344, manufactured by Dainippon Ink Chemical Co., Ltd.) and 1 part by weight of lead octylate were dissolved in 90 parts by weight of xylene to form a conductive elastic layer of the static eliminating charge member. Dip coating on the
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 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 static elimination/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 was dissolved in 90 parts by weight of methanol, and the solution was dip-coated on the conductive elastic layer of the static-eliminating charging member,
After drying, a resin layer having a film thickness of 1100 μm 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 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 (manufactured by Nippon Polyurethane) in polyester polyol and 2 parts by weight of toluylene diisocyanate were dissolved in 90 parts by weight of n-butanol, and the solution was dip-coated on the conductive elastic layer of the static elimination charging member,
After drying, a resin layer having a film thickness of 1100 μm 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 static eliminator charging member of the present invention, as shown in 3.

This was evaluated in the same manner as in Example 5, and as can be seen by comparing Example 5.6 and Comparative Examples 10 and 11.12 in the table, the present invention can suppress the residual potential and prevent the occurrence of soil blur and wavy fog. .

Furthermore, as can be seen by comparing Example 5.6 and Comparative Example 9.11, it is possible to prevent the charging member from fusing with the photoreceptor and to suppress the occurrence of horizontal stripe defective images.

[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 sections 4, 5, and 6 are cross-sections of an electrophotographic device. It is a diagram. la conductive support, lb = conductive sheet metal, 14: 15: 16 - conductive elastic layer, 3: resin layer, protective layer, 5 - resin powder, charging member, 7: image exposure means, developing means, Corona charger for transfer charging, cleaning means, 11: pre-exposure means, electrophotographic photoreceptor, corona charger for primary charging, charging member for transfer charging, charging member for neutralizing charge. Agent Patent Attorney Johei Yamashita

Claims (4)

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