JP2003107820A - Electrophotographic member production method and electrophotographic member produced by the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an excellent electrophotographic member production method and an electrophotographic member produced by the method. SOLUTION: The electrophotographic member production method uses an agitation device that agitates and disperses coating composition, the device having a container with a circular cross-section which is capable of storing the coating composition to be agitated, a rotary shaft disposed in the center of the container, and an agitation tool that is attached to the rotary shaft and rotates at a high speed and its radius reaches the proximity of the internal surface of the container. Also in the method, the agitation tool is driven at a high speed at a peripheral speed of 20 m/sec or higher, in order to firmly attach the coating composition to the internal face of the container by means of centrifugal force, and the coating composition agitated and dispersed while rotated in the form of a hollow thin film is used in order to form a coating layer on the surface of the electrophotographic member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic method used for developing a latent image formed on a latent image carrier carrying an electrostatic latent image with a developer carried and carried by the carrier. In particular, the present invention relates to a member used in electrophotography having a cylindrical or columnar substrate and a coating layer formed on the substrate, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a large number of electrophotographic methods have been known. Generally, a photoconductive substance is used to form an electric latent image on a photoconductor by various means, and then the latent image is developed with a toner (developer) to form a visible image. A copy can be obtained by transferring the toner image on a transfer material such as paper, if necessary, and then fixing the toner image on the transfer material by heat, pressure or the like.

In each of these electrophotographic processes, for example, as shown in FIG. 3, many cylindrical members or cylindrical members are used. More specifically, there are a photosensitive drum, a charging roller, a developing sleeve (developer carrying member), a transfer roller, a fixing roller and the like. A coating layer is formed on each of these cylindrical or columnar members, if necessary, for the purpose of adjusting resistance, controlling chargeability, imparting releasability, improving durability, controlling transportability, and the like.

For example, in a developer carrier, various resin layers have been proposed on the surface of a substrate in order to optimize charging of toner. In the one-component developing method, the developer carrying member and the photoconductor on which the latent image is formed are brought into contact with each other in the developing area, or the thickness of the developer layer on the developer carrying member forms the latent image with the developer carrying member. And a non-contact development (jumping development) in which the thickness of the developer layer on the developer carrier is less than the minimum gap between the developer carrier and the photoreceptor. ) Method is common.

A rubber roller is usually used in the method in which the developer carrying member is in direct contact with the photosensitive member. When the developer carrying member is not in contact with the photosensitive member, a rigid sleeve or resin such as aluminum or SUS is used. Generally, a sleeve or the like is used. When either of these is used, the surface coating layer is often formed and used as described above. As an example of forming a surface coating layer on these developer carrying members, JP-A-1
JP-A-277265 and JP-A-3-200986 disclose a resin coating layer containing conductive fine particles on a conductive substrate for the purpose of preventing excessive charging (charge-up) of the toner on the developer carrier. Are disclosed.

In the charging member, conventionally, a non-contact type corona charger is often used as a charging means for uniformly charging a latent image carrier such as an electrophotographic photoreceptor or an electrostatic recording dielectric. However, this corona charging often generates corona products such as ozone and requires additional means / mechanisms to remove them, so the entire device tends to be large and complicated. Has been pointed out as a problem, and as ecology has been attracting attention in recent years, since it has advantages such as low ozone and low power, contact type charging devices such as rubber roller, fixed brush, fur brush, magnetic brush, etc. are used. What was used has been put to practical use.

For example, in a member that comes into direct contact with the photosensitive member, especially in a charging rubber roller, the rubber contains impurities such as a plasticizer, a vulcanizing agent, a release agent, and a low molecular weight component.
These components bleed to contaminate the photoconductor or the cleaning member or chip or crack the blade or the photoconductor to adversely affect the image. For the purpose of preventing this, a resin coating layer called a surface layer or a protective layer is often formed on the roller surface for use. For example, Japanese Patent No. 2864782 discloses that a surface coating layer is formed for the purpose of preventing bleeding of the plasticizer or the like in the elastic layer to the surface.

Further, the magnetic brush charging device uses a member in which magnetic particles are restrained by a magnetic force on a carrier so as to be attached and held as a magnetic brush. The magnetic brush is brought into contact with a member to be charged and a voltage is applied to the member. The charging member is charged, and for example, in JP-A-08-254880, a surface coating layer is formed on the surface of the magnetic particle carrying member of the magnetic brush charging member in order to stabilize the transportability of the magnetic particles. Is proposed.

Further, as the fixing roller, a fixing device of a heat roller type is generally used. In this fixing device, the fixing roller, a pressure roller rotatably pressed against the fixing roller, and the surface of the fixing roller are heated to a predetermined temperature. And a separation claw for preventing the transfer material from being wound around the fixing roller.

The image is fixed by being heated and pressed by passing an unfixed toner image on the transfer material to a nip portion composed of a fixing roller and a pressure roller to obtain a permanent image on the transfer material. For the purpose of improving the releasability between the fixing roller and the toner in order to suppress the occurrence of an offset phenomenon in which the toner is transferred to the surface of the fixing roller, for example, JP-A-6-186881 discloses a fluororesin such as PTFE. It is disclosed that a coating layer consisting of is formed on the surface of the fixing roller.

As a coating method for forming these coating layers, a coating method in which solid particles are dispersed in a resin dissolved and / or dispersed in a dispersion solvent is used, such as a dipping method, a spray method or a brush coating method. It is generally done by the method.

On the other hand, as means for dispersing the solid particles in the resin dissolved and / or dispersed in the above-mentioned dispersion solvent, by using media such as beads, the collision force or shearing force between the liquid paint and the beads is utilized. There are beads mills and sand mills. As these dispersion media, those that are hard and have excellent wear resistance such as stainless steel, alumina, zirconia, and porcelain are generally used.

Further, as another dispersion method, there is a three-roll mill or the like in which compression is performed by a gap between rolls and the shearing force is used for dispersion. In a dispersing device such as a three-roll mill, since the roller surface is open, the solvent has a large volatilization loss, and there are drawbacks in terms of cost and environmental hygiene. Therefore, it is rarely used in recent synthetic resin paints. Further, the roll mill is inferior in dispersion power to the bead mill and the sand mill.

[0014]

However, the surface physical properties and the durability required for the developing member and the charging member, which have a great influence on the image quality with the recent improvement in the image quality of electrophotography and the speeding up of the electrophotographic apparatus, have become difficult. Requirements are becoming more sophisticated. For this reason, it is necessary to stably obtain high image quality and high speed performance over a long period of time, and a more uniformly formed coating layer is required.

These coating layers are used for the purpose of controlling conductivity, optimizing charge imparting ability to toner, preventing toner adhesion, improving durability of the coating layer, forming uniform surface irregularities, metal or metal oxide particles, Generally, various solid particles such as carbon-based particles, ceramic-based particles, resin particles, solid lubricant particles, and conductive particles are formed using a paint in which a solvent or a resin dissolved in a solvent is dispersed according to the purpose. Target.

However, for example, a coating layer using a coating material to which particles having a large difference in specific gravity from the coating resin dissolved in a solvent, particles having a high agglomeration property, particles having a small particle size such as conductive fine particles are added are used. When forming the, in the conventional bead mill or sand mill dispersion method, the particle size distribution of the added particles in the coating is likely to be a wide distribution, because the dispersion of the added particles in the coating layer becomes uneven, Problems such as local variation of volume resistance and non-uniformity of surface roughness occurred. This is because the dispersion state of the solid particles in the paint is insufficient by the conventional dispersion method, so that the separation of the solid particles from the resin in the paint or the coarse particles made of agglomerates of the solid particles occurs in the paint. It is thought to be caused by doing.

Furthermore, the coating layer in which the added particles are insufficiently dispersed as described above causes a decrease in the strength of the coating layer, is less likely to suffer abrasion, peeling, scratches, etc., and has durability against repeated use, Inferior in wear resistance.

Further, when a coating layer in which the added particles are insufficiently dispersed as described above is used for the developer carrying member, the surface shape of the coating layer and the dispersion of the added particles are not uniform, so that the developer is conveyed. In some cases, image defects such as density unevenness and streaks due to non-uniformity of the toner and non-uniformity of imparting charge to the developer, and image defects such as streaks due to scratches on the developer layer thickness controlling blade may occur.

Further, when a coating layer in which the added particles are insufficiently dispersed as described above is used as a charging member, the surface shape and volume resistance of the coating layer are non-uniform, so that charge is imparted to the body to be charged. Is insufficient or non-uniform, so that image defects such as density unevenness and density decrease are likely to occur.

Further, as described above, the dispersion of the coating material by the conventionally used bead mill or sand mill uses a medium having excellent abrasion resistance as a medium. There is a problem that the medium is abraded by the collision between the medium and the medium and impurities are mixed in the coating composition.

Therefore, an object of the present invention is to solve the above problems and to add particles having a difference in specific gravity to the resin forming the coating layer or particles having high cohesiveness in the paint, and particles such as conductive particles. Forming a uniform coating layer that does not cause aggregation or separation of particles in the coating layer and does not cause coating defects such as protrusions, coating unevenness, appearance of the base material, etc. even when a small diameter is added It is to provide a manufacturing method.

A further object of the present invention is to provide a production method in which the coating layer has a desired surface shape and a uniform distribution of the added particles in the coating layer. A further object of the present invention is to provide a method for producing a coating layer which is resistant to abrasion, peeling, scratches, etc. of the coating layer and has durability and wear resistance against repeated use.

A further object of the present invention is to provide a developer carrier which does not cause image defects such as density unevenness and streaks due to non-uniformity in developer transport and non-uniformity in imparting charge to the developer. . Further, the object of the present invention is that the coating layer has a desired surface shape and a uniform dispersion of the added particles in the coating layer, the developer layer thickness regulating blade is less likely to be scratched, and defects such as streaks on the image are generated. Is to provide a developer carrying member which does not show.

Further, the object of the present invention is to develop a coating layer which is resistant to abrasion, peeling, scratches, etc., has durability against repeated use, and has abrasion resistance, and which can stably obtain a good image for a long period of time. It is to provide an agent carrier.

Further, an object of the present invention is to provide a magnetic particle conveying member in which the resistance value of the coating layer is uniform, charge can be sufficiently applied to the charged body, and image defects such as density unevenness and density decrease do not occur. It is to provide a charging device.

A further object of the present invention is that the coating layer has a desired surface profile and a uniform distribution of added particles in the coating layer.
It is an object of the present invention to provide a magnetic particle conveying member and a charging device that can stably and uniformly convey magnetic particles and can uniformly apply an electric charge to an object to be charged.

Further, the object of the present invention is to prevent abrasion, peeling, scratches, etc. of the coating layer, durability for repeated use and wear resistance, and stable and uniform transport of magnetic particles for a long period of time. Another object of the present invention is to provide a magnetic particle conveying member and a charging device capable of uniformly applying an electric charge to an object to be charged.

[0028]

The above object can be achieved by the present invention described below. That is, the present invention is a member used in an electrophotographic method having a coating layer formed by using a coating material obtained by stirring and dispersing a coating material composition containing at least solid particles and a dispersion solvent on a cylindrical or cylindrical substrate. In the manufacturing method of the above, as a stirring device used for the stirring dispersion, a container having a circular cross section capable of accommodating the coating composition to be stirred, a rotating shaft provided at the center of the container, and the rotating shaft attached to the rotating shaft A stirrer having a stirrer rotating at a high speed having a radius reaching the vicinity of the inner peripheral surface of the container is used, and the stirrer is driven at high speed at a peripheral speed of 20 m / sec or more to centrifuge the coating composition by centrifugal force. Provided is a method for producing an electrophotographic member, characterized in that a coating layer is formed on the surface of the member by using a paint which is pressed against the inner surface and is stirred and dispersed in a hollow thin film while rotating.

The present invention also provides the member manufactured by the above manufacturing method, particularly the developer carrying member, the magnetic particle carrying member and the charging member manufactured by the above manufacturing method.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the following preferred embodiments. First, a method for stirring and dispersing the coating composition for forming the coating layer used in the present invention will be described.

In the present invention, as the stirring device used for the stirring dispersion, as described above, a container having a circular cross section capable of accommodating the coating composition to be stirred, and a rotating shaft provided at the center of the container. And a stirring device having a high-speed rotating stirring tool having a radius reaching the vicinity of the inner peripheral surface of the container attached to the rotating shaft, and the stirring tool is rotated at a peripheral speed of 20 m /
One characteristic is that the coating composition is pressure-bonded to the inner surface of the container by centrifugal force by being driven at a high speed for more than sec and is stirred and dispersed while being rotated in the form of a hollow thin film. When the agitator rotates at a high peripheral speed, the coating composition is forcibly rotated along with it, and is pressed against the inner surface of the container by a centrifugal force to form a hollow thin film and rotates.

The rotation of the coating composition occurs not only in the portion in contact with the stirring tool but also in the portion away from the stirring tool as the coating composition rotated by the stirring tool moves. The rotation is transmitted to the coating composition through the rotation of air, and the coating composition is rotated.

At this time, since the rotation speed of the stirring tool is higher than the rotation speed of the coating composition and the gap between the inner peripheral surface of the container and the end of the stirring tool is small, the coating composition existing near the end of the stirring section. Is agitated with a stirrer to produce a high degree of dispersion,
Agglomeration of solid particles in the coating composition is small, and the particle size distribution in the coating is uniform. Here, the gap between the end of the stirrer and the inner peripheral surface of the container is not particularly limited as long as the coating composition is formed into a hollow thin film as described above. It is about 1 to 20 mm.

The peripheral speed of the stirring tool is 20 m / sec or more, preferably 25 m / sec. If the peripheral speed of the stirrer is less than 20 m / sec, a hollow thin film cannot be sufficiently formed, and the dispersibility of solid particles in the paint will be insufficient.

Specific examples of the stirring and dispersing device include the device described in Japanese Patent Application Laid-Open No. 9-75698. K. Commercially available products such as Filmix (manufactured by Tokushu Kika Kogyo Co., Ltd.) can be used. Next, as a method for coating the coating material treated with the stirring and dispersing device on the cylindrical or columnar substrate, known methods such as a spray method, a dipping method, and a brush coating method can be used. In order to impart a uniform surface shape with the solid particles dispersed therein, the spray method is preferable, and among them, the air spray method is more preferable.

Next, a developer carrying member will be described as an example of the electrophotographic member according to the present invention. The developer carrying member is composed of a base and a coating layer surrounding and covering the base. The base may be a cylindrical member, a cylindrical member or the like. A cylindrical tube or a solid rod such as the above is preferably used. As such a substrate, a non-magnetic metal or alloy such as aluminum, stainless steel, or brass, which is molded into a cylindrical shape or a cylindrical shape, and which is polished or ground is preferably used.

These substrates are used by being molded or processed with high precision in order to improve the uniformity of images. For example, the straightness in the longitudinal direction is 30 μm or less or 20 μm.
m or less, and more preferably 10 μm or less, and the deflection of the gap between the sleeve and the photosensitive drum, for example, the deflection of the gap between the vertical surface and the vertical surface when the sleeve is rotated by abutting it with a uniform spacer. Is preferably 30 μm or less, or 20 μm or less, and more preferably 10 μm or less. Aluminum is preferably used in terms of material cost and workability. Those having such a form are preferably used as a developer carrier base for magnetic and non-magnetic one-component non-contact development and two-component development.

Further, as the substrate having an elastic layer, a core member and a cylindrical member having a layer structure containing rubber or elastomer such as urethane, EPDM, and silicon are used. Particularly, the latent image holding member is brought into direct contact with the developer carrying member. It is preferably used in the case of a developing method.

In general, the coating material for forming the coating layer preferably contains a binder resin in order to enhance the coating property of the coating layer, the coating strength, and the charge imparting property to the developer. As the binder resin material, generally known resins can be used.
For example, styrene resin, vinyl resin, polyether sulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, fluororesin, fibrin resin, thermoplastic resin such as acrylic resin, epoxy resin, polyester resin, alkyd resin A thermosetting or photocurable resin such as a phenol resin, a melamine resin, a polyurethane resin, a urea resin, a silicone resin or a polyimide resin can be used. Among them, those with releasability such as silicone resin and fluororesin, or excellent mechanical properties such as polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane, styrene resin, acrylic resin More preferred are:

As the solvent for dissolving or dispersing the binder resin, for example, methyl ethyl ketone (ME
K), methanol, xylene, methyl cellosolve, toluene, chlorobenzene, dichloromethane, isopropyl alcohol (IPA), butanol, ethyl acetate, butyl acetate, etc., any of the conventionally known substances can be used, but the addition particles are not particularly limited. Dispersion stability, viscosity,
It is preferably selected in consideration of thixotropic properties, coatability at the time of coating, film-forming properties, and the like.

In the present invention, the amount of the solvent contained in the coating composition used for stirring and dispersing is 50% by mass or more, preferably 60% by mass or more. When the amount of the solvent added is less than 50% by mass, it is difficult to uniformly disperse the solid particles in the paint, which is not preferable.

In the coating material for forming the coating layer on the surface of the developer carrying member, in addition to the binder resin, the resistance value of the coating layer is adjusted, the adhesion of toner is reduced, the surface roughness is stabilized, and the toner is charged. Solid particles such as conductive particles, lubricating particles, charge controllable particles, and particles having a particle size of 1 to 25 μm for forming surface irregularities or for imparting film hardness, depending on the purpose of each member used such as control of performance. Are dispersedly used.

In the present invention, the coating layer formed on the developer carrying member by the above-mentioned forming material is caused by the sticking of the developer onto the developer carrying member by charge-up or the charge-up of the developer. In order to prevent defective charging from the surface of the developer carrier to the developer, it is preferably conductive.

In order to adjust the conductivity of this coating layer,
It is preferable that the conductive particles listed below are dispersed and contained in the coating material. The conductive particles used in this case,
Examples thereof include metal powders such as aluminum, copper, nickel and silver, metal oxides such as antimony oxide, indium oxide and tin oxide, carbon materials such as carbon fiber, carbon black and graphite.

Of these, carbon black, particularly conductive amorphous carbon, is particularly excellent in electrical conductivity, and is filled with a polymer material to impart electrical conductivity, and at the same time, the amount added is controlled to a certain degree. It is preferably used because it can obtain the electric conductivity of.
Further, the addition amount of these conductive materials is 100
It is preferable to set the range of 1 to 100 parts by mass with respect to parts by mass. If it is less than 1 part by mass, it is usually difficult to reduce the volume resistance of the coating layer to a desired level, and toner adhesion to the binder resin used in the developer carrier coating layer is likely to occur. If it exceeds 100 parts by mass, the strength of the coating layer may decrease, especially when fine particles having a particle size of submicron order are used.

When the conductive particles are dispersed in the coating material by using the stirring / dispersing device used in the present invention, even if the particle size of the conductive particles is small, they are less likely to aggregate as secondary particles,
Since the particles are uniformly dispersed in the primary particles, a uniform and low resistance value is obtained even if the amount of the conductive agent contained in the coating layer is relatively small, the strength of the coating layer is improved, and the uniform developer is uniformly charged. It will be possible.

On the other hand, when dispersed by a sand mill using a conventional medium, the conductive particles are not sufficiently dispersed,
In order to reduce the resistance of the coating layer, a large amount of conductive particles must be added, and the strength of the coating layer and the charge on the developer are likely to be uneven.

The volume resistance of the coating layer is preferably 1
It is 0 ⁴ Ω · cm or less, more preferably 10 ³ Ω · cm or less. The volume resistance of the coating layer on the surface of the developer carrier is 10 ⁴
If it exceeds Ω · cm, a charge imparting failure to the developer is likely to occur, and as a result, image unevenness due to charge-up may occur.

By dispersing solid particles having an average particle size of 1 to 25 μm in the coating material forming the coating layer of the present invention,
It is possible to form an uneven shape on the surface of the coating layer to optimize the developer coating amount on the developer carrier and the magnetic particle coating amount on the magnetic particle conveying member.

If the average particle size of the solid particles that impart irregularities to the surface is less than 1 μm, sufficient surface roughness for stabilizing the transportability of the developer cannot be formed on the surface of the coating layer.

When it exceeds 25 μm, the roughness of the surface of the coating layer becomes too large and the surface shape tends to become non-uniform, resulting in poor charging of the developer, deterioration of the strength of the coating layer and damage to the surface of the developer regulating member. There are cases.

When the coating layer of the present invention is used as a developer carrying member, the solid particles form a surface roughness having a uniform unevenness on the surface of the coating layer of the developer carrying member, and at the same time, the solid particles are coated. Even when the layer surface is worn, the change in surface roughness of the coating layer is small, and it is effective in preventing toner contamination and toner fusion.

As these solid particles, particles which are less likely to be worn or scraped due to durability are preferable. For example, phenol resin, acrylic resin, urethane resin, polyethylene resin, polypropylene resin, polystyrene resin, benzoguanamine resin, polyamide resin, fluorine resin. Resin particles having high mechanical strength such as silicone resin, epoxy resin, and polyester resin are used. In order to improve the durability of the coating layer, carbon-based particles, and for further improving the durability, inorganic particles having a Mohs hardness of 4 or more such as metal or metal oxide, silica, alumina, aluminum borate, and boron carbide. Is preferably used.

The amount of particles used for stabilizing the surface roughness is 1 with respect to 100 parts by mass of the binder resin.
It is preferably in the range of 100 to 100 parts by mass. When the amount of the solid particles that impart irregularities to the surface of the binder resin is less than 1 part by mass, sufficient surface roughness for stabilizing the transportability of the developer cannot be formed on the surface of the coating layer. On the other hand, when it exceeds 100 parts by mass, the uneven shape of the surface of the coating layer is likely to be non-uniform, which may result in poor charging of the developer, reduction in strength of the coating layer, or damage to the surface of the developer regulating member.

When the unevenness-imparting particles are dispersed in the coating material by using the stirring / dispersing device used in the present invention, the particles are aggregated with each other even if inorganic particles having high aggregability such as boron carbide are used. Is uniformly dispersed without forming a particle, and the shape of the particles is rounded due to the absence of sharp portions due to dispersion, so that the surface shape of the coating layer is uniform and there are no sharp portions, and the developer regulating member is The abrasion resistance of the coating layer is improved without damaging it.

On the other hand, when the dispersion is carried out by a sand mill using a conventional medium, the dispersion of the inorganic particles in the coating layer is insufficient and there are aggregated lumps of particles and sharp particles, and the surface shape of the coating layer is not uniform. In some cases, the strength of the coating layer may be reduced, the protrusions present on the surface of the coating layer may damage the developer regulating member, and the unevenness of the developer transportability may cause image unevenness.

Further, in the coating material forming the coating layer, in order to further reduce the adhesion of the developer to the surface of the coating layer, the lubricating particles are mixed alone or in addition to the above-mentioned solid particles in the coating layer. You can also let it. Examples of the lubricating particles that can be used in this case include molybdenum disulfide, boron nitride,
Examples thereof include graphite, graphite fluoride, tungsten disulfide, silver-selenniobium, calcium chloride-graphite, talc, fluorine-based resin particles, polyamide resin particles, polyethylene resin particles and polyacetal resin particles. The addition amount of these solid lubricants is preferably in the range of 1 to 100 parts by mass with respect to 100 parts by mass of the binder resin. When the addition amount of the solid lubricant is less than 1 part by mass with respect to the binder resin, the effect of imparting lubricity to the surface of the coating layer is poor, and the effect of improving the adhesiveness of the developer to the surface of the coating layer is small. On the other hand, if the amount exceeds 100 parts by mass, the strength of the coating layer may decrease.

These solid lubricants have an average particle size of preferably 0.2 to 20 μm, more preferably 1 to 15 μm. If the average particle size of the solid lubricant is less than 0.2 μm, sufficient lubricity cannot be obtained and the strength of the coating layer tends to decrease, and if it exceeds 20 μm, the influence on the shape of the coating layer surface increases. However, the surface is not uniform, which is not preferable in terms of uniform charging of the developer and strength of the coating layer.

When the lubricating particles are dispersed in the coating material by using the stirring / dispersing device used in the present invention, even particles such as graphite and molybdenum disulfide which are prone to cleaving do not leave coarse particles in the coating material. In addition, the particle size distribution can be uniformly dispersed by appropriately refining the particles, and the shape of the coating layer surface can be made uniform, the effect of the lubricant can be improved, and the wear resistance can be improved.

On the other hand, when the particles are dispersed by a sand mill using a conventional medium, the dispersion of the lubricating particles in the coating is insufficient, coarse particles are likely to exist in the coating layer, and the lubricating particles are crushed. Since it easily occurs and a large amount of fine particles are generated, the particle size distribution becomes a broad dispersion, the surface shape of the coating layer becomes uneven, the strength of the coating layer decreases, the lubrication effect decreases, and the protrusions existing on the surface of the coating layer. There may be a case where the developer regulating member is damaged due to the above, and image unevenness or the like occurs due to non-uniformity of the developer carrying property.

Charge controllable particles may be added to the coating material forming the coating layer in order to control the charge imparting ability of the coating layer to the toner. Examples of the charge controllable particles include, for example, modified products of nigrosine and fatty acid metal salts, quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and the like. Onium salts such as phosphonium salts, which are analogs, and lake pigments thereof (the laking agents include phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, and ferrocyanine). Etc.) Metal salts of higher fatty acids; Diorganotin oxides such as butyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; Diols such as dibutyltin borate, dioctyltin borate, dicyclohexyltin borate. Nosuzuboreto like; guanidine, imidazole compounds, fluorine-based resin, a polyamide resin, an acrylic resin or the like, nitrogen-containing, and the like. Further, the addition amount of these charge controllable particles is 1 to 100 with respect to 100 parts by mass of the binder resin.
It is preferably within the range of parts by mass.

When the addition amount of the charge controllable particles is less than 1 part by mass with respect to the binder resin, the effect of charge controllability on the surface of the coating layer is poor and it is difficult to quickly impart charge to the developer.
On the other hand, when it exceeds 100 parts by mass, the strength of the coating layer is reduced and the volume resistance is increased, so that charge-up of the toner is likely to occur.

When the charge control particles are dispersed in the coating material by using the stirring / dispersing device used in the present invention, it becomes possible to disperse the charge control particles uniformly in the coating material, and even if a small amount of the charge control particles is added to the coating layer. The chargeability of the surface of the coating layer becomes uniform, and the developer can be quickly and uniformly imparted with a charge.

On the other hand, when the particles are dispersed by a sand mill using a conventional medium, the dispersion of the charging particles in the coating is insufficient, and therefore, in order to bring out the effect of the charge controllable particles, the charging layer is charged. Since a large amount of control particles must be added, the strength of the coating layer may decrease, and the resistance of the coating layer may increase, which may cause image unevenness due to charge-up of the developer.

The viscosity of the coating composition containing these is preferably 10 to 400 mPa · s, and more preferably 20 to 300 mPa · s. The viscosity of the paint is 10mP
If it is less than a · s, sagging or unevenness of the coating layer, separation of solid particles in the coating layer, and the like become severe, which is not preferable. On the other hand, when the viscosity of the coating material exceeds 400 mPa · s, solid particles in the coating material tend to agglomerate, and it becomes difficult to obtain a coating layer having a uniform surface shape.

The coating layer of the present invention has an average particle size of 1 to 25.
By dispersing the solid particles of μm, it is possible to form an uneven shape on the surface and optimize the developer coating amount on the developer carrier and the magnetic particle coating amount on the magnetic particle conveying member.

The surface roughness of the coating layer of the present invention is JI
The S arithmetic mean roughness (Ra) is preferably in the range of 0.4 to 3.5 μm. More preferably, it is 0.5 to 3 μm. That is, when Ra is less than 0.4 μm, the amount of the developer coated on the developer carrier becomes insufficient, and the transportability of the developer is significantly reduced due to a slight abrasion of the coating layer surface.
This causes deterioration of ghost and reduction of image density due to charge-up of the developer. On the other hand, Ra is 3.5 μm
If it exceeds, uneven developer and fog may occur due to uneven coating of the developer and non-uniform triboelectric charging of the developer. The Ra on the surface of the coating layer can be controlled to 0.4 to 3.5 μm easily by changing the volume particle diameter and the addition amount of the solid particles dispersed in the coating layer.

In order to form and maintain a uniform surface roughness on the surface of the coating layer of the developer carrier, the ten-point average roughness Rz of the coating layer on the surface of the developer carrier is 1.5 times the average particle diameter of the solid particles. The following is preferable.

When the ten-point average roughness Rz of the coating layer exceeds 1.5 times the average particle size of the particles, the protrusions become the leak points of the developing bias, and the unevenness of the image on the image caused by uneven charging of the latent image carrier. Image defects such as fog and density unevenness are generated because the developer cannot be triboelectrically charged around the defects and protrusions.

Further, the protrusions are likely to damage the developer layer thickness regulating member (blade), and toner fusion to the blades is likely to occur in the vicinity of the protrusions. Uneven density and fog are likely to appear. Also,
The roughness of the surface coating layer drops sharply at the beginning due to image formation,
As a result, a decrease in image density and uneven density are likely to occur.

Further, it is preferable that Rz / Ra, which is the ratio of the ten-point average roughness Rz and the arithmetic average roughness Ra of the surface coating layer formed of the coating composition, is 9 or less. Rz
When / Ra exceeds 9, the uniform surface roughness of the surface is insufficient, and the triboelectrification of the developer tends to be uneven,
Fog images are likely to occur.

When the irregularity-imparting particles are dispersed in the coating material using the stirring / dispersing device used in the present invention, the dispersibility of the irregularity-imparting particles in the coating layer is good, and the surface shape is uniform, and the coating layer is It is easy to control the 10-point average roughness Rz of 1.5 times or less of the average particle diameter of the particles, and the Rz / Ra ratio is 9
It will be easier to control below.

Next, a developing device and an image forming apparatus in which the above-described developer carrying member of the present invention is incorporated will be described. FIG. 1 is a schematic diagram of a developing device that is an embodiment of the present invention.

In FIG. 1, an electrostatic latent image holding member that holds an electrostatic latent image formed by a known process, for example, the electrophotographic photosensitive drum 1 is rotated in the direction of arrow B. The developer carrying member 8 as a developer carrying member carries the one-component developer 4 having magnetic toner supplied by the hopper 3 as a developer container, and rotates in the direction of arrow A to develop the developer. The developer 4 is conveyed to the developing area D where the carrier 8 and the photosensitive drum 1 face each other. As shown in FIG. 1, the developer carrier 8 is filled with the developer 4.
A magnet roller 5 in which a magnet is inscribed is arranged on the top for magnetic attraction and holding.

The developer carrier 8 used in the developing device of the present invention has a conductive coating layer 7 coated on a metal cylindrical tube 6 as a substrate. A stirring blade 10 for stirring the developer 4 is provided in the hopper 3. Reference numeral 11 is a gap indicating that the developer carrying member 8 and the photosensitive drum 1 are in a non-contact state.

The developer 4 generates a triboelectric charge capable of developing the electrostatic latent image on the photosensitive drum 1 by friction between the magnetic toners and the conductive coating layer 7 on the developer carrier 8. obtain. In the example of FIG. 1, in order to regulate the layer thickness of the developer 4 conveyed to the developing area D, the magnetic regulation blade 2 made of a ferromagnetic metal as a developer layer thickness regulating member is provided on the developer carrier 8. It is suspended from the hopper 3 so as to face the developer carrying member 8 with a gap width of about 50 to 500 μm from the surface.

By concentrating the magnetic force lines from the magnetic pole N1 of the magnet roller 5 on the magnetic regulation blade 2, a thin layer of the developer 4 is formed on the developer carrier 8. In the present invention, a non-magnetic blade may be used instead of the magnetic regulation blade 2. In this way, the thickness of the thin layer of the developer 4 formed on the developer carrier 8 is thinner than the minimum gap between the developer carrier 8 and the photosensitive drum 1 in the developing area D. Preferably there is.

The developer carrying member of the present invention is a developing device of the type which develops an electrostatic latent image by a thin layer of the developer as described above.
That is, it is particularly effective to incorporate the non-contact type developing device, but in the developing area D, the thickness of the developer layer is equal to or larger than the minimum gap between the developer carrier 8 and the photosensitive drum 1. That is, the developer carrying member of the present invention can be applied to a contact type developing device. To avoid complicated explanations,
In the following description, the non-contact type developing device as described above will be taken as an example.

In order to fly the one-component developer 4 having the magnetic toner carried on the developer carrier 8, a developing bias voltage is applied to the developer carrier 8 by a developing bias power source 9 as a bias means. To be done. When a DC voltage is used as the developing bias voltage, a voltage having a value between the potential of the image portion (the area where the developer 4 is adhered and visualized) of the electrostatic latent image and the potential of the background portion is used as the developer. It is preferable to apply it to the carrier 8.

In order to increase the density of the developed image or improve the gradation, an alternating bias voltage is applied to the developer carrying member 8 and an oscillating electric field whose direction is alternately inverted is applied to the developing area D. You may form. In this case, it is preferable to apply to the developer carrier 8 an alternating bias voltage in which a DC voltage component having an intermediate value between the potential of the developed image portion and the potential of the background portion is superimposed.

In the case of so-called normal development, in which toner is visualized by adhering toner to the high-potential portion of the electrostatic latent image having the high-potential portion and the low-potential portion, the electrostatic latent image is charged to the opposite polarity. Use toner. In the case of so-called reversal development, in which toner is attached to the low potential part of an electrostatic latent image having a high potential part and a low potential part to make it visible, a toner charged to the same polarity as the polarity of the electrostatic latent image is used. To do. High potential and low potential are expressions using absolute values. In any of these cases, the developer 4 is charged by friction with at least the developer carrier 8.

FIG. 2 is a structural schematic diagram showing another embodiment of the developing device of the present invention, and FIG. 3 is a structural schematic diagram showing still another embodiment of the developing device of the present invention.

In the developing device shown in FIGS. 2 and 3, the developer layer thickness regulating member for regulating the layer thickness of the developer 4 on the developer carrying member 8 has rubber elasticity such as urethane rubber or silicone rubber. An elastic regulating blade 2 made of an elastic plate made of a material or a material having metallic elasticity such as phosphor bronze or stainless steel is used. The elastic regulating blade 2 is opposite to the rotating direction of the developer carrying member 8 in the developing device of FIG. 3 is characterized in that the elastic regulating blade 2 is brought into pressure contact with the direction of rotation of the developer carrying member 8 in the forward direction.

In these developing devices, a developer layer thickness regulating member is elastically pressed against the developer carrying member 8 via the developer layer, whereby a thin layer of the developer is formed on the developer carrying member. Therefore, it is possible to form a thinner developer layer on the developer carrier 8 than in the case of FIG. 1 described above.

The other basic structure of the developing device shown in FIGS. 2 and 3 is the same as that of the developing device shown in FIG. 1, and the same reference numerals indicate basically the same members. Figure 1
Reference numeral 3 is merely a schematic illustration of the developing device of the present invention, and the shape of the developer container (hopper 3) and the stirring blade 1 are shown.
It goes without saying that there are various forms of the presence or absence of 0 and the arrangement of magnetic poles. Of course, these devices can also be used for development (FIG. 4) using a two-component developer containing toner and carrier.

Next, the toner used in the developing device of the present invention will be described. Toner is mainly composed of resin, release agent,
It is a fine powder in which a charge control agent, a colorant, and the like are melt-kneaded, solidified, and then pulverized, and then classified, and the particle size distribution is made uniform. As the binder resin used in the toner, generally known resins can be used.

For example, styrene, α-methylstyrene,
Homopolymers of styrene such as p-chlorostyrene and its substitution products; styrene-propylene copolymers, styrene-vinyltoluene copolymers, styrene-ethyl acrylate copolymers, styrene-butyl acrylate copolymers, styrene. -Octyl acrylate copolymer, styrene-dimethylaminoethyl copolymer, styrene-methylmethacrylate copolymer, styrene-ethylmethacrylate copolymer, styrene-butylmethacrylate copolymer, styrene-dimethylaminomethacrylate Ethyl copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester Styrenic copolymers such as copolymers; Methyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, temper resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, paraffin Wax, carnauba wax and the like can be used alone or in combination.

Further, the toner may contain a pigment. For example, carbon black, nigrosine dye,
Lamp Black, Sudan Black SM, First Yellow G, Benzidine Yellow, Pigment Yellow,
India First Orange, Irgadine Red, Paranitroaniline Red, Toluidine Red, Carmine FB, Permanent Bordeaux FRR, Pigment Orange R, Resor Red 2G, Rake Red C, Rhodamine FB, Rhodamine B Lake, Methyl.・ Violet B Lake, Phthalocyanine Blue, Pigment Blue, Brilliant Green B, Phthalocyanine Green, Oil Yellow GG, Pomelo First Yellow CGG, Kayaset Y963, Kayaset Y
G, pomelo first orange RR, oil scarlet, orazol brown B, pomelo first scarlet CG, oil pink OP, etc. can be applied.

In order to use the toner as a magnetic toner,
Magnetic powder may be contained in the toner. As such magnetic powder, a substance that is magnetized in a magnetic field is used, and examples thereof include powders of ferromagnetic metals such as iron, cobalt and nickel, and alloys and compounds such as magnetite, hematite and ferrite. The content of the magnetic powder is preferably 15 to 70 mass% with respect to the toner mass.

The toner may contain waxes for the purpose of improving releasability during fixing and fixing property. Examples of such waxes include paraffin wax and its derivatives, microcrystalline wax and its derivatives, Fischer-Tropsch wax and its derivatives, polyolefin wax and its derivatives, carnauba wax and its derivatives, etc. Includes block copolymers and graft modified products with vinyl monomers. In addition, alcohols, fatty acids, acid amides, esters, ketones, hydrogenated castor oil and its derivatives, plant waxes, animal waxes, mineral waxes, petrolactam and the like can be used.

If necessary, the toner may contain a charge control agent. The charge control agents include negative charge control agents and positive charge control agents. For example, the following substances are used to control the toner to be negatively charged. For example, organic metal complexes and chelate compounds are effective, and there are monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid metal complexes. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

Further, the substances for positively charging the toner are as follows. Modified products of nigrosine and fatty acid metal salts, quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and onium such as phosphonium salts which are analogs thereof. Salts and lake pigments thereof (as a laking agent, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.), metal salts of higher fatty acids Dibutyltin oxide,
Diorgano tin oxides such as dioctyl tin oxide and dicyclohexyl tin oxide; Diorgano tin borates such as dibutyl tin borate, dioctyl tin borate and dicyclohexyl tin borate; guanidine compounds and imidazole compounds.

The toner may be used by externally adding powder such as inorganic fine powder for the purpose of improving fluidity and the like. Examples of such fine powders include silica fine powder, metal oxides such as alumina, titania, germanium oxide, and zirconium oxide; carbides such as silicon carbide and titanium carbide; and inorganic fine powders such as nitrides such as silicon nitride and germanium nitride. The body is used.

These fine powders can be used after being organically treated with an organic silicon compound, a titanium coupling agent and the like. For example, as the organosilicon compound, hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromine. Methyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate,
Vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane, and 2 to 12 per molecule. 1 unit for each terminal unit with siloxane units
There is dimethyl polysiloxane containing a hydroxyl group bonded to Si for individual pieces.

Alternatively, an untreated fine powder treated with a nitrogen-containing silane coupling agent may be used. Particularly, positive toner is preferable. Examples of such treating agents include aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane,
Dibutylaminopropyltrimethoxysilane, monobutylaminopropyltrimethoxysilane, dioctylaminopropyltrimethoxysilane, dibutylaminopropyldimethoxysilane, dibutylaminopropylmonomethoxysilane, dimethylaminophenyltrimethoxysilane, trimethoxysilyl-γ-propylphenyl There are amine, trimethoxysilyl-γ-propylbenzylamine, trimethoxysilyl-γ-propylpiperidine, trimethoxysilyl-γ-propylmorpholine, trimethoxysilyl-γ-propylimidazole and the like.

As the method for treating the inorganic fine powder with the silane coupling agent, for example, 1) a spray method,
2) Organic solvent method, 3) Aqueous solution method and the like. Generally, the treatment by the spray method is a method in which the pigment is stirred, an aqueous solution of a coupling agent or a solvent solution is sprayed thereon, and then water or the solvent is removed and dried at about 120 to 130 ° C. Further, the treatment by the organic solvent method means an organic solvent (alcohol, which contains a hydrolysis catalyst together with a small amount of water).
A coupling agent is dissolved in benzene, halogenated hydrocarbons, etc., and a pigment is immersed in this, followed by solid-liquid separation by filtration or compression and drying at about 120 to 130 ° C. The aqueous solution method is a method in which about 0.5% of a coupling agent is hydrolyzed in water or a water-solvent having a constant pH, the pigment is immersed therein, and then solid-liquid separation is similarly performed and drying is performed. .

As another organic treatment, it is also possible to use fine powder treated with silicone oil. The preferred silicone oil has a viscosity at 25 ° C. of about 0.5 to 10000 mm ² / sec, preferably 1 to 1
000 mm ² / sec is used, for example, methylhydrogen silicone oil, dimethyl silicone oil, phenylmethyl silicone oil, chlorophenylmethyl silicone oil, alkyl modified silicone oil, fatty acid modified silicone oil, polyoxyalkylene modified silicone oil, Examples thereof include fluorine-modified silicone oil.

Further, silicone oil having a nitrogen atom in its side chain may be used. Particularly, positive toner is preferable. The treatment with silicone oil can be performed, for example, as follows. The pigment is violently stirred while being heated if necessary, and the silicone oil or the solution thereof is sprayed or vaporized and sprayed on the pigment, or the pigment is made into a slurry, and the silicone oil or the silicone oil is stirred with stirring. It can be easily processed by dropping the solution. These silicone oils may be used alone or as a mixture of two or more, or may be used in combination or in multiple treatments. Further, the treatment with a silane coupling agent may be used together.

When such a toner is used after being subjected to a spheroidizing treatment and a surface smoothing treatment by various methods, it is preferable because the transferability becomes good. As such a method, a device having a stirring blade or a blade and the like, and a liner or a casing and the like, for example, when passing the toner through a minute gap between the blade and the liner, the surface is smoothed by a mechanical force. There are a method of making the toner spherical, a method of making the toner spherical by suspending the toner in warm water, and a method of making the toner spherical by exposing the toner to a hot air stream.

As a method of producing spherical toner,
There is a method in which a mixture containing a monomer as a toner binder resin as a main component is suspended in water and polymerized to form a toner. As a general method, a polymerizable monomer, a colorant, a polymerization initiator, and if necessary, a crosslinking agent, a charge control agent, a release agent, and other additives are uniformly dissolved or dispersed to form a single amount. After a body composition, this monomer composition is a continuous layer containing a dispersion stabilizer, for example, dispersed in a water phase to a suitable particle size using a suitable stirrer, further polymerization reaction, This is a method of obtaining a developer having a desired particle size.

The toner may be mixed with a carrier and used as a two-component developer. As a carrier material,
For example, magnetic metal such as iron, nickel, cobalt,
And alloys thereof, or alloys containing rare earths, iron such as hematite, magnetite, manganese-zinc ferrite, nickel-zinc ferrite, manganese-magnesium ferrite and lithium ferrite, and other soft ferrites, copper-zinc ferrite Examples thereof include a system oxide, a mixture thereof, ceramic particles such as glass and silicon carbide, a resin powder, a resin powder containing a magnetic material, and the like.
It is used as a granular material of about 300 μm.

As such a carrier, the above-mentioned granular materials may be directly used as carrier particles, but in order to adjust the triboelectric charge of the toner and prevent toner spent on the carrier, a silicone resin, Fluorine resin,
It is also possible to appropriately coat the surface of the particles with a resin using a coating agent such as acrylic resin or phenol resin.

Next, the magnetic brush charging member of the present invention and the magnetic particle carrying member used therefor will be described. The method of forming the coating layer of the magnetic particle transport member can be performed in the same manner as in the case of the developer carrier. The paint used for forming the coating layer of the magnetic particle transport member of the present invention will be described. The following inorganic particles having a Mohs hardness of 4 or more are dispersed and contained in a coating material as a reinforcing filler for imparting uniform roughness to the surface of the coating layer of the magnetic particle conveying member of the present invention and improving wear resistance. Preferably.

Fe, and Fe, C, Ni, Cr, Mo,
Iron alloy containing Mn, Ti, SiAl, V, etc .; Al and Cu, Si, Fe, Mn, Mg, Zn, Cr, T in Al
Aluminum alloy containing i, etc .; Mg and Al in Mg,
Magnesium alloy containing Zn, Mn, Zr, Th, etc .;
Cu and Cu with As, Te, Os, Ag, Si, Sn,
Pb, Be, Cr, Co, Cd, Ni, Al, Zn, M
Copper alloy containing n, Fe, P, Se, Te, etc .; Ni and Ni with C, Mn, Fe, S, Si, Cu, Cr, Mo,
Nickel alloy containing Al, Ti, Co, P, W, V, Ta, Nb, etc .; Sb, Te, As, S in Pb and Pb
n, Ca, Na, Fe, Ni, Ag, Bi, Zn, Si
Lead alloy containing Sb and Sb; Antimony alloy containing Sn, Cu, Pb, etc .; Bi and Sb containing Sn and Sn;
Tin alloy containing Pb, Ag, Zn, Al, Mg, Co, Mn, Te, etc .;

Zn, Zn, Zr, Mn, Al, Cu,
Zinc alloy containing Mg, Fe, etc .; Cd and N in Cd
Cadmium alloy containing i, Ag, Au, Cu, Zn, etc .; Al and Zn, Pb, Sn, Cd, L in Bi and Bi
Bismuth alloy containing i, etc .; Ti and Al, M in addition to Ti
n, Fe, Sn, Mo, V, Zn, Pb, Ta, Zr,
Titanium alloy containing Pt, Pd, etc .; Zr and M for Zr
o, W, Ti, B, Al, Sn, Ge, Sb, Pb, T
1P, In, Nb, Ta, V, U, Cr, Mn, Fe,
Zirconium alloy containing Co, Ni, Cu, Hf, etc .;
Ta and Ta with W, Fe, Ni, Co, Cr, Nb, Z
Tantalum alloy containing r, etc .; Nb and Nb, Ta, W,
Cr, Ni, Zr, Al, Ti, Mo, V, Hf, C,
Niobium alloy containing Y, Co, etc .; W and W containing Ti and C
Tungsten alloy containing o, Cr, V, C, Cu, Ni, etc .;

Fe and Al, Mo, Ni, Cr,
Chromium alloy containing Co, W, Mo, etc .; Mo and Mo with Ti, Co, Cr, V, C, Cu, Ni, Nb, Ta,
Molybdenum alloy containing etc .; Co and Co with Cr, N
Cobalt alloy containing i, Mo, Fe, Si, W, N, Nb, C, etc .; Fe, Ni, Mn, Mo, Cr in V and V
Vanadium alloy containing etc .; Ag and Cu, Z in Ag
n, Al, Sb, Mg, Mn, Hg, Pd, Pt, T
l, Sn, Si, Li, Se, Te, Ni, Cr, F
Ag alloy containing e, Mo, Ta, W, V, Co, Ir, Rh, etc .; Ag and Cu, Pt, Pd, N in Au and Au.
Au alloy containing i, Zn, Al, etc .;

Pt and Rh, Ir, Ru, Ni,
Pt alloy containing W, Pd, etc .; Ag, C in Pd and Pd
Pd alloy containing u, Ru, Rh, etc .; N in Rh and Rh
Rh alloy containing i and the like; Ir alloy containing Ir and Pt and the like in Ir; Os and Os alloy containing Pt and the like in Os and R; R
Ru alloy containing Pt, Pd, etc. in u and Ru; Cr
₃ P, CrP, Au ₂ P, MnP ₂ , Mo ₃ P, MoP ₃ ,
Ni ₃ P, Ni ₂ P, Rh ₂ P, SiP, TaP, Ti
P, WP, Zn ₃ P ₂ , ZrP _{2 and} other phosphorus metal compounds;

Ga: Ge and Ge containing Ge and Ge
Alloy; As and As alloy containing Pb, Cu, Ga, In, etc. in As; Se; Te; Li and Li, Mg, Al,
Li alloy containing Zn, Pb, Fe, Hg, Tl, Sn, etc .; Be alloy containing Cu, Co, Ni, Al, Fe, etc. in Be and Be; In in Mn and Mn; La in Ce and Ce; Ce alloy containing Nb, Fe, Mg, Al, Zn, etc .;

Alternatively, BeO, MgO, CaO, Ba
O, B₂O₃, Al₂O₃, MgAl₂O_Four, BeAl ₂O_Four,
Ga₂O₃, In₂O₃, GeO₂, SnO₂, PbO, Pb
₃O_Four, PbO₂, SB₂O₃, Bi₂O₃, SeO₂, TeO
₂, TiO₂, Al₂TiO_Five, ZrO₂, Cr₂O₃, Cr
O₂, MnO₂, Α-Fe₂O₃, Β-Fe₂O₃, Fe
₃O_Four, CuO, ZnO, V₂O_Five, SiO₂, Zn₂SiO
_Four, ZrSiO_FourOxides of

BN, AlN, Si₃N_Four, TiN, Zr
Nitride such as N, TaN, NbN; SiC, ZrC, W
C, TiC, MoC, B_FourCarbonization of C, diamond, etc.
Thing; TiB₂, AlB₁₂, ZrB₂, HfB₂, VB₂, N
bB₂, TaB₂, CrB₂, Mo₂B_Five, W₂B_Five, Fe
₂B, FeB, CoB, NiB, LaB₆, EuB₆, U
B_Four, UB₁₂, CaB₆, SiB₆, B_FourC, β-B, BN
Boride; TiSi₂, ZrSi ₂, VSi₂, Nb
Si₂, TaSi₂, CrSi₂, MoSi₂, WSi₂etc
Silicide of;

For example, Al₂O₃・ 2SiO₂・ 2H₂O,
Al₂O₃・ 4SiO₂・ H₂O, Al ₂O₃・ 2SiO₂,
Al₂O₃・ SiO₂3 Al₂O₃・ 2SiO₂Such as
Aluminic acid alumina, for example, K2O.Al₂O₃・ 6Si
O₂, Na₂O ・ Al₂O₃・ 6 SiO₂, K₂O / 3Al₂
O₃・ 6 SiO₂・ 3H₂O, Na₂O ・ 2MgO ・ 5Al
₂O ₃・ 24 SiO₂・ (6 + n) H₂O, K₂O ・ Al₂O
₃・ 4SiO₂Such as alumina alumina silicate, for example
For example, 2MgO / SiO₂・ 2Al₂O₃3MgO / 4S
iO₂3MgO ・ 4SiO₂・ H₂O, 3MgO / 2S
iO₂・ 2H₂O, 2MgO / SiO₂Such as silicate
Silicates such as gnesium; Sulfides such as phosphorus sulfide, ZnS
Things etc. are mentioned.

These may be used alone or as a main component.
It may be a mixed crystal, a composite, or a mixture as a component. Well
Replaced some atoms of these compounds with other atoms
It may be a compound. Inorganic powder containing multiple inorganic powders
Good. Furthermore, ultrafine inorganic particles, etc., are applied to the surface of these inorganic powders.
Those that have been subjected to doping or plasma treatment (for example, Al
₂O₃A composite of powder coated with ultrafine Ni particles plasmatized
SnO for powder and TiO₂System-treated Sb-doped powder
Body) can be used. As the shape of these powders
Is not particularly limited and is generally known as spherical, angular, plate
Shapes, needles, whiskers, and irregular shapes are used.
It Also, these reinforcing fillers are not limited to one type
Types may be added.

The hardness thereof is Mohs' hardness of 4 or more, more preferably 5 or more. When the Mohs hardness is less than 4, the magnetic particles accelerate wear of the coating layer, the coating amount of the magnetic particles decreases, the magnetic particles contaminate the toner, and toner fusion occurs, resulting in defective charge injection to the surface of the photoconductor. I will end up. The average particle size of these solid particles is 1 to
Those having 25 μm are preferred.

When the average particle diameter of the solid particles is less than 1 μm, it becomes difficult to increase the surface roughness of the surface of the magnetic particle conveying member, the conveying force of the magnetic particles is reduced, and the abrasion of the coating layer due to the magnetic particles is reduced. Decrease the coating amount of magnetic particles,
Contamination and fusion due to magnetic particles occur, which causes defective charge injection to the surface of the photoreceptor, which is not preferable. On the other hand, if the average particle size exceeds 25 μm, the roughness of the surface of the coating layer becomes too large and the coating amount of the magnetic particles increases too much. It is not preferable because the mechanical strength is reduced.

The amount of inorganic particles having a Mohs hardness of 4 or more as a reinforcing filler for imparting a uniform roughness to the surface of the coating layer and improving wear resistance is 1 with respect to 100 parts by mass of the binder resin. It is preferably in the range of 100 to 100 parts by mass.
When the amount of the solid particles is less than 1 part by mass with respect to the binder resin, sufficient surface roughness that stabilizes the developer transportability cannot be formed on the surface of the coating layer. On the other hand, when it exceeds 100 parts by mass, the mechanical strength of the coating layer is lowered, and the unevenness of the coating layer surface is likely to be nonuniform, and the roughness of the coating layer surface becomes too large to coat the magnetic particles. The amount is too large, and similarly, charge injection failure to the surface of the photoconductor is caused, which is not preferable.

As the binder resin material for the coating layer, known resins similar to those shown for the developer carrier can be used, but those having excellent mechanical strength are particularly preferable.
Further, in order to adjust the resistance value of this coating layer, the conductive substance described above can be used. It is preferable to disperse and contain these conductive substances in the paint to adjust the resistance.

The particle size of the conductive amorphous carbon used in the present invention is preferably 10 to 80 mμm. Dispersion of these solid particles in the coating material can be carried out by using the stirring / dispersing device used in the present invention, which makes it possible to uniformly disperse the particle size distribution in the coating material as shown in the developer carrier. Further, it is possible to achieve uniform shape of the surface of the coating layer and improvement of wear resistance.

Next, the magnetic particle carrying member will be described. The magnetic particle conveying member is a magnetic body in which magnetic particles are restrained by a magnetic force and attached and held as a magnetic brush. The magnetic brush is brought into contact with an object to be charged, and a voltage is applied to charge the object to be charged. It is a thing. More specifically, 1) The magnetic particle conveying member is a rotatable sleeve, and a fixed magnet roll (magnet) arranged in the sleeve.
The magnetic particles are bound to the outer surface of the sleeve by the magnetic force of and are attached and held as a magnetic brush (sleeve type). 2) The magnetic particle conveying member is a rotatable magnet roll, which is directly attached to the outer surface of the roll. The magnetic particles are bound by magnetic force and attached and held as a magnetic brush (magnetic roller type).

FIG. 5 is a schematic diagram of the configuration of the sleeve type magnetic particle carrying member 2 or the charging device of the above 1). Reference numeral 21 is a non-magnetic conductive sleeve (electrode sleeve, conductive sleeve, etc.) made of aluminum or the like as a magnetic particle conveying member.
It is also called a charging sleeve).

Reference numeral 22 is a magnet roll as a magnetic field generating means inserted and arranged in the sleeve 21. N and S are magnetized portions of the roll. The magnet roll 22 is a non-rotating fixed member, and the outer circumference of the magnet roll 22 is concentrically driven by the sleeve 21 to rotate in the clockwise direction indicated by an arrow at a predetermined peripheral speed by a drive mechanism (not shown).

Reference numeral 23 is a conductive magnetic particle (hereinafter referred to as a carrier), which is bound to the outer peripheral surface of the sleeve 21 by the magnetic force of the magnet roll 22 inside the sleeve as a magnetic brush (conductive magnetic brush) B. Is held.
The carrier 23 forms a magnetic spike on the outer surface of the sleeve 21 due to the magnetic restraining force of the magnet roll 22, and these are gathered into a brush shape. S1 is a charging bias application power source for the sleeve 21.

Reference numeral 1 is a member to be charged, which is, for example, a drum type electrophotographic photosensitive member which is rotationally driven in the clockwise direction a indicated by an arrow at a predetermined process speed. The magnetic particle carrying member 2 is arranged in a state in which the magnetic brush B is brought into contact with the surface of the charged body 1 to form a charging nip portion (contact nip portion) D.

The magnetic brush B is rotatively conveyed in the same direction as the sleeve 21 rotates, and rubs the surface of the rotating photoconductor 1 at the charging nip portion D, and is applied to the magnetic brush B from the power source S1 via the sleeve 21. The charging bias generated
The surface of the rotary photoconductor 1 as the member to be charged is charged by a contact method. In the charging nip portion D, the rotating direction of the sleeve 21 and the accompanying rotating and conveying direction of the magnetic brush B are counter directions with respect to the rotating direction of the rotary photoconductor 1 as the charged body. The sleeve 21 has a carrying function for the magnetic brush B, a carrying function, and a charging bias application electrode function.

FIG. 6 is a schematic model view of the magnetic roller type magnetic particle conveying member 2 or the charging device of 2). The magnet roll 22 is a central core metal 2 that both drives and feeds electricity.
4 is rotated at a predetermined peripheral speed by a drive mechanism (not shown) in a clockwise direction b indicated by an arrow. Magnet roll 22
The outer peripheral surface of is covered with a conductive layer 25 as a charging bias applying electrode (power feeding surface). The carrier 23 is restrained by the magnetic force of the magnet roll 22 on the outer peripheral surface of the conductive layer 25 to be attached and held as a magnetic brush B.

The magnetic brush B is rotatably conveyed in the same direction as the magnet roll 22 rotates, and rubs against the surface of the rotating photoconductor 1 at the charging nip D, and from the power source S1 to the central core metal 24 of the magnet roll 22. By the applied charging bias, the surface of the rotating photoconductor 1 as the member to be charged is contact-charged. The conductive layer 25 provided on the outer peripheral surface of the magnet roll 22 serves to stably and uniformly supply the charging bias to the magnetic brush B. Further, the surface layer can be formed on a rubber roller used as a charging roller or a developing roller by the same method. FIG. 7 shows an example thereof.

FIG. 8 is a schematic view of an example of the image forming apparatus. The image forming apparatus of this example is a process cartridge mounting / demounting system,
It is a laser beam printer (LBP) using a transfer type electrophotographic process. Further, the image carrier is an OPC photosensitive member having a charge injection function on its surface, and the magnetic particle carrying member is used as a contact charging member, and the image carrier is subjected to a primary charging process by an injection charging method.

Reference numeral 1 is a rotary drum type electrophotographic photosensitive member as an image bearing member, and in this example, it is an OPC photosensitive member having a diameter of 30 mm and having a charge injection function on the surface thereof, and is in a clockwise direction a as indicated by an arrow. It is rotationally driven at a process speed (peripheral speed) of 100 mm / sec. Reference numeral 2 is a contact charging member for uniformly charging the peripheral surface of the photoconductor 1 to a predetermined polarity and potential, and in this example, it is the sleeve type magnetic particle conveying member shown in FIG.

The conductive sleeve 21 of the magnetic particle carrying member 2 is at least a cylindrical or columnar member having a surface coating layer. A DC bias of -700V is applied to the sleeve 21 of the magnetic particle carrying member 2 from the charging bias applying power source S1, and the outer peripheral surface of the rotating photoconductor 1 is uniformly charged to approximately -700V by charge injection charging. It

A laser whose intensity is modulated corresponding to the time-series electric digital pixel signal of the target image information output from the laser beam scanner 7 including a laser diode, a polygon mirror, etc. on the charged surface of the rotating photosensitive member 1. Scanning exposure L is performed by the beam, and an electrostatic latent image corresponding to target image information is formed on the peripheral surface of the rotating photoconductor 1.

A case where the electrostatic latent image is developed as a toner image by the reversal developing device 3 using magnetic one-component insulating toner (negative toner) will be described, but the non-magnetic two-component toner (negative toner) is also used in the same manner. be able to.

Reference numeral 3a is a non-magnetic developing sleeve having a diameter of 16 mm and containing the magnet 3b. The developing sleeve 3a was coated with the above negative toner to fix the gap (separation distance) from the surface of the photosensitive member 1 to 300 μm. In this state, the photoconductor 1 is rotated at the same speed, and a developing bias voltage is applied from the developing bias power source S2 to the developing sleeve 3a.
DC voltage of -500V and frequency 1800H
z and a rectangular AC voltage having a peak-to-peak voltage of 1600 V are superimposed, and jumping development is performed between the sleeve 3 a and the photoconductor 1. That is, the negatively charged toner carried by the developing sleeve 3a is attached to the image portion of the latent image by an electric field to develop the latent image.

On the other hand, a transfer material P serving as a recording material is supplied from a paper feeding unit (not shown), and the rotary photosensitive member 1 and the contact transfer means that is brought into contact with the rotary photosensitive member 1 with a predetermined pressing force have a medium resistance. It is introduced into the pressure contact nip portion (transfer portion) T with the transfer roller 4 at a predetermined timing. A predetermined transfer bias voltage is applied to the transfer roller 4 from the transfer bias applying power source S3. In this example, a transfer roller 4 having a resistance value of 5 × 10 ⁸ Ω with a medium resistance foam layer formed on a core metal is used, and a DC voltage of +2000 V is applied to the core metal to charge and transfer the back surface of the transfer material. I went.

The transfer material P introduced into the transfer section T is nipped and conveyed by the transfer section T, and the toner images formed and carried on the surface of the rotary photoconductor 1 are sequentially held on the surface side thereof by electrostatic force and pressing force. Will be transcribed. The transfer material P that has received the transfer of the toner image is separated from the surface of the photoconductor 1 and is introduced into a fixing device 5 such as a thermal fixing system to be fixed with the toner image, and is transferred outside the device as an image formed product (print, copy). Is discharged to.

Further, the surface of the photosensitive member after the transfer of the toner image onto the transfer material P is cleaned by the cleaning device 6 to remove adhering contaminants such as residual toner, and is repeatedly used for image formation. In the image forming apparatus of this example, the process cartridge 10 including the photoconductor 1, the magnetic particle conveying member 2, the developing device 3, and the cleaning device 6 is collectively detachable and replaceable with respect to the main body of the image forming apparatus. is there. Reference numeral 9 is a cartridge housing in which the above four process devices 1, 2, 3, and 6 are incorporated in a predetermined arrangement. 8
Is a process cartridge insertion / removal guide / holding unit on the image forming apparatus main body side.

In the state where the process cartridge 10 is mounted in the image forming apparatus main body in a predetermined manner, the process cartridge 10 side and the image forming apparatus main body side are mechanically
The two are electrically coupled to each other, and the lower surface of the photoconductor 1 on the process cartridge 10 side comes into contact with the transfer roller 4 on the image forming apparatus main body side in a predetermined manner, so that the image formation can be performed.

The process cartridge is a cartridge in which the charging means, the developing means or the cleaning means, and the electrophotographic photosensitive member are integrally formed, and the cartridge can be attached to and detached from the main body of the image forming apparatus. Further, at least one of the charging means, the developing means, and the cleaning means and the electrophotographic photosensitive member are integrally made into a cartridge so that it can be attached to and detached from the main body of the image forming apparatus. Furthermore,
At least the developing means and the electrophotographic photosensitive member are integrally made into a cartridge which can be attached to and detached from the apparatus main body.

FIG. 9 is a schematic diagram of the layer structure of the photoconductor 1 as the member to be charged. The photoconductor 1 is a negatively charged OPC photoconductor having a charge injection function on its surface, and has the following first to fifth five functional layers 12 to 16 on a drum base 11 made of aluminum having a diameter of 30 mm in order from the bottom. It is provided.

The first layer is the undercoat layer 12, which is provided to smooth out defects on the outer peripheral surface of the aluminum drum substrate 11 and to prevent moire due to reflection of laser exposure. It is a conductive layer of 20 μm. The second layer is a positive charge injection preventing layer 13, which plays a role of preventing the positive charges injected from the aluminum substrate 11 from canceling out the negative charges charged on the surface of the photoconductor, and the amylan resin and methoxymethylated nylon 10 ⁶ Ω · cm
It is a medium resistance layer having a thickness of about 1 μm whose resistance is adjusted to some extent.

The third layer is the charge generation layer 14, which is a layer having a thickness of about 0.3 μm in which a disazo pigment is dispersed in a resin, and generates positive and negative charge pairs by being exposed to laser. The fourth layer is the charge transport layer 15, which is a polycarbonate resin in which hydrazone is dispersed, and is a P-type semiconductor. Therefore, the negative charges charged on the surface of the photoconductor cannot move in this layer, and only the positive charges generated in the charge generation layer 13 can be transported to the surface of the photoconductor.

The fifth layer is the charge injection layer 16 and is photocurable.
Ultrafine conductive particles (conductive filler) on acrylic resin
SnO as 16a₂Is a coating layer of a material in which is dispersed.
Specifically, antimony was doped to reduce the resistance.
SnO with a particle size of about 0.03 μm ₂70 particles to resin
It is a coating layer of a material in which mass% is dispersed. In this way
About 2 μm thick with the combined coating solution by dipping coating method
To form a charge injection layer. As a result,
The surface resistance is 1 × 10 for the charge transport layer alone.¹⁵Ω · cm
1 × 10 compared to¹³It dropped to Ω · cm.

The charge injection layer 16 intentionally creates injection sites for uniformly charging the surface by directly injecting charges from the magnetic particle carrying member 2. The charge injection layer 16 has a resistance of 1 × so as not to flow.
It should be 10 ⁸ Ω · cm or more. Charge injection layer 16
The resistance value is obtained by applying a charge injection layer on an insulating sheet and measuring the surface resistance of the charge injection layer with a high resistance meter 4329A manufactured by HP at an applied voltage of 100V.

Although the charge injection layer 16 is formed as an independent layer in this example, it is important that the surface layer of the photoconductor has an electron level capable of donating electrons, and the structure is limited to the structure having the charge injection layer independently. Not something to do. In order to reduce the adhesion of carriers (magnetic particles) on the magnetic particle conveying member side to the surface of the photoconductor, it is preferable that the photoconductor 1 has a characteristic of low surface energy, and a desired lubricant is added to the outermost surface of the photoconductor to make it uniform. It has smoothness.

The charge injection charging of the photoconductor is a medium resistance contact charging member for injecting charge into the surface of the photoconductor having a medium resistance surface resistance. The charge is injected into the trap potential of the surface material of the photoconductor. However, this is a method of charging the conductive particles 16a of the charge injection layer 16 with electric charges.
By applying a desired voltage to the magnetic particle carrying member 2 at the time of charging, charges are injected into the charge injection layer 16 and the surface of the photoreceptor 1 as a charged body is finally charged (charged) to the same potential as the magnetic brush B. To be done.

Specifically, as shown in the model diagrams and equivalent circuit diagrams of FIGS. 10A and 10B, the photoreceptor 1 uses the charge transport layer 15 as a dielectric, and the aluminum drum base 11 and the charge injection layer. The conductive particles 16a (SnO ₂ ) in the layer 16 can be regarded as a parallel assembly of minute capacitors having both electrode plates, and the injection charging charges the individual minute capacitors with the contact charging member 2. It is based on theory.

The conductive particles 16a are electrically independent of each other and form a kind of minute float electrode. For this reason, the surface of the photoconductor 1 seems to be charged and charged to a uniform potential on a macroscopic scale, but in reality, a myriad of charged electrically conductive particles 16a cover the photoconductor surface. Has become. Therefore, even if the image exposure L is performed by the laser, the conductive particles 16a are electrically independent, so that it is possible to hold the electrostatic latent image.

Magnetic particle conveying member 2 as a contact charging member
Is a sleeve type similar to the one described above. That is, the non-magnetic conductive sleeve 21 (hereinafter, referred to as “rotating carrier” that holds the carrier 23 constituting the magnetic brush B)
The sleeve 2 or the electrode sleeve).
The carrier 23 is constrained to the outer surface of the sleeve 21 by the magnetic force of the fixed magnet roll 22 arranged in the inside 1, and is attached and held as the magnetic brush B.

The material of the sleeve 21 is a metal such as aluminum, stainless steel or brass, an aluminum alloy, an indium oxide-tin oxide alloy, a plastic having a coating layer of these metals or alloys, and a paper impregnated with conductive particles. Any non-magnetic material can be used, such as a cylindrical cylinder such as a plastic, a plastic having a conductive polymer, and a film. Aluminum is most preferable from the viewpoint of cost and workability.

The surface of the sleeve 21 is coated with a coating material and dried to provide a coating layer (not shown). The magnetic flux density by the magnet roll 22 on the sleeve 21 is 8 × 10 ^-2
It was T (Tesla). Carrier 23 on sleeve 21
Is coated with a thickness of 1 mm to form and hold a magnetic brush B, and the magnetic brush B is contacted by forming a charging nip portion D having a width of about 5 mm between the magnetic brush B and the photosensitive member 1 and contacting the sleeve 21. Rotate counter to surface.

The contact width in the longitudinal direction between the magnetic brush B and the photosensitive member 1 is 200 mm. The magnetic brush B rotates in the same direction as the sleeve 21 rotates, and the carrier 23 constituting the magnetic brush is conveyed, and the carriers come into contact with the surface of the photoconductor 1 one after another. In this example, the magnetic brush B has a carrier amount of about 10 g, and the gap between the electrode sleeve 21 and the photoconductor 1 at the charging nip portion D is 500 μm.

The peripheral speed ratio between the magnetic brush B and the photosensitive member 1 is defined by the following equation. Peripheral speed ratio% = (magnetic brush peripheral speed-photoconductor peripheral speed) / photoconductor peripheral speed x 100 * The peripheral speed of the magnetic brush is a negative value when counter rotation is performed. Magnetic brush B stops at a peripheral speed ratio of -100%. Since it is in the state of being charged, the stopped shape on the surface of the magnetic brush B on the surface of the photoconductor directly becomes defective in charging and appears on the image. Further, in the forward rotation, when the magnetic brush B comes into contact with the photoconductor 1 at a low speed, the carrier 23 of the magnetic brush B easily adheres to the photoconductor 1 and an attempt is made to obtain the same peripheral speed ratio as in the counter direction. Therefore, the rotation speed of the magnetic brush B becomes high. Therefore, the peripheral speed ratio is preferably −100% or less, and in this embodiment, it is −150%.

The carrier 23 constituting the magnetic brush B includes: a resin and a magnetic powder such as magnetite which are kneaded and molded into particles, or a conductive carbon which is mixed to adjust the resistance value. -Sintered magnetite, ferrite, or those whose resistance value has been adjusted by reducing or oxidizing them-Coated with a coating material (such as phenol resin with carbon dispersed) whose resistance has been adjusted, or Ni, etc. It is conceivable that the resistance value is adjusted to an appropriate value by plating with the above metal.

The volume resistance value of these carriers 23 is preferably 1 × 10 ⁴ to 1 × 10 ¹¹ Ω · cm. If it is less than 1 × 10 ⁴ Ω · cm, when there is a pinhole on the surface of the photoconductor, the current concentrates on the pinhole, the charging voltage drops, and the surface of the photoconductor cannot be charged. Becomes If it exceeds 1 × 10 ¹¹ Ω · cm, charges cannot be evenly injected into the photoconductor 1, resulting in a fog image due to minute charging failure.

Therefore, the resistance value of the carrier 23 is 1
It is preferably × 10 ⁴ to 1 × 10 ¹¹ Ω · cm,
Particularly, it is preferably 1 × 10 ⁴ to 1 × 10 ⁷ Ω · cm. The resistance value of the carrier 23 is set such that 2 g of the carrier is put into a metal cell (bottom area 228 mm ² ) to which a voltage can be applied and then weighted, and the voltage is 1 to 1000 V from the top and bottom, for example, 10
It was defined as a value obtained by applying 0 V and calculating from the measured current flowing in this system and normalizing it. It is also possible to improve the chargeability by mixing and using a plurality of types of carriers.

If the particle size of the carrier 23 is too small, the magnetic restraining force becomes small and the carrier adheres to the surface of the photoreceptor 1. On the other hand, if it is too large, the contact area with the photoconductor 1 is reduced and charging failure increases. Therefore, the average particle size of the carrier is preferably about 5 to 50 μm from the viewpoint of chargeability and magnetic retention.

Regarding the magnetic characteristics of the carrier, it is better to increase the magnetic restraining force in order to prevent the carrier from adhering to the photosensitive member, and the saturation magnetization is preferably 30 A · m ² / kg or more. The carrier 23 actually used in this example has an average particle diameter of 30 μm, an irregular shape, and a resistance value of 1 × 10 ⁶ Ω.
Cm, and saturation magnetization was 58 A · m ² / kg.

Since the coating layer also serves as an electrode layer,
As the resin component, it is necessary to use a material having good conductivity or an insulating resin mixed with a conductive agent so as to have conductivity. In addition, the resistance value of the coating layer is 2
It is preferable to set the resistance value lower than the resistance value of the carrier 23 by one digit or more so that a sufficient current can be supplied to the carrier 3.

By forming irregularities on the surface of the electrode sleeve 21, the contact area between the electrode sleeve 21 and the carrier 23 is expanded, and the contact resistance between them is reduced, so that it is possible to obtain a good charging property. Further, since the frictional force between the sleeve 21 and the carrier 23 also increases, the sleeve 21 as the carrier of the carrier 23 forming the magnetic brush B in the charging nip portion D faces the photoconductor 1 as the charged body. Carrier 2 of magnetic brush B at the gap
3 can be carried smoothly, and the deterioration of the charging property due to the retention of the carrier 23 in the charging nip portion D can be prevented.

Therefore, as the optimum average surface roughness of the electrode sleeve 21, the arithmetic average roughness Ra is 0.4 to 3.5.
The range of μm is preferable, and 0.5 to 3.0 μm is more preferable. Ra of the electrode sleeve 21 is 0.4 μm
If it is smaller, the number of contact points between the electrode sleeve 21 and the carrier 23 decreases, and the contact resistance increases, and at the same time, the coating amount of the magnetic particles decreases remarkably even in a state where the coating layer wears little. On the contrary, R of the electrode sleeve 21
When a is larger than 3.5 μm, the carrier 23 is embedded in the surface of the electrode sleeve 21 and the contact resistance does not change any more. The Ra of the surface coating layer can be controlled to 0.4 to 3.5 μm by changing the average particle diameter and the addition amount of the solid particles dispersed in the surface coating layer.

Furthermore, the ten-point average roughness Rz of the coating layer is preferably 1.5 times or less the average particle size of the added solid fine particles. If Rz exceeds 1.5 times the average particle diameter of the solid fine particles added, current concentrates on the protrusions and sudden leakage occurs, which tends to cause uneven charging. In addition, the roughness of the coating layer is sharply reduced in the initial stage, which tends to cause uneven transportation of magnetic particles and uneven charging.

Further, Rz / Ra, which is the ratio of the ten-point average roughness Rz and the arithmetic average roughness Ra of the surface coating layer, is preferably 9 or less. When Rz / Ra exceeds 9, the uniform surface roughness is still insufficient, and therefore, when the image is repeatedly formed, uneven charging easily occurs due to uneven transfer. In this embodiment, the LB using the OPC photoconductor is used.
Although it has been described using P, it can be similarly used in a copying machine using an OPC photosensitive member or an amorphous Si photosensitive member.

[0161]

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples. In the text, "part" or "%" is based on mass unless otherwise specified. <Example 1> -Resol type phenol resin (containing 50% of methanol) 600 parts-Carbon black (average particle size 0.039 μm) 100
Parts / methanol 300 parts A coating material was prepared using the above materials.

The above material was used as T.W. K. Using FILMIX (manufactured by Tokushu Kika Kogyo Co., Ltd.), a peripheral speed of 50 m / sec was dispersed for 3 minutes with a brush-shaped stirrer having a gap of 2 mm from the inside of the container. Methanol was further added to adjust the solid concentration to about 36.
% And then passed through a 350 mesh sieve to paint A
-1 was created. When the viscosity of this paint was measured at room temperature, it was 45 mPa · s. Further, when the particle size distribution of this coating material was measured, the center diameter was 0.6 μm and the standard deviation was 0.31 μm, showing a uniform particle size distribution.

A cylindrical tube having an outer diameter of 32 mmφ obtained by cutting an aluminum cylindrical tube was blasted with alundum particles to obtain a ten-point average roughness Rz of 9.1 μm and an arithmetic average roughness Ra of 0.89 μm. And A work having a developing sleeve flange attached to one side thereof was prepared. The work was set up on a rotary table, rotated while masking the end of the sleeve, and the above paint 1 was spray-applied to the work with a spray gun while descending at a constant speed to obtain a coating sleeve. This was dried and cured at 150 ° C. for 30 minutes with a ventilation dryer to form a coating layer. At this time, the thickness of the surface coating layer was 12.5 μm, the ten-point average roughness Rz was 6.13 μm,
The arithmetic average roughness Ra was 0.73 μm. The volume resistance value of the coating layer was 1.35 Ω · cm.

The material composition ratio of the coating material is shown in Table 1, the dispersion conditions and physical properties of the coating material are shown in Table 2, and the physical properties of the coating layer are shown in Table 3.

A magnet is attached to the developing sleeve, and a stainless steel flange is fitted to the developing sleeve.
It can be installed in the developing device of P-6085 modified machine. The modified NP-6085 machine used in this experiment is a modified 85-sheet machine to a 95-sheet machine with a process speed of 513
mm / sec. 573 mm / sec. And the sleeve peripheral speed was 1.8 times the drum peripheral speed. While supplying magnetic toner (below), continuous durability up to 500,000 sheets was evaluated. Environment is 24 ℃
It was performed in a room temperature and low humidity (N / L) environment of / 10%. The results are shown in Table 3. Good results were obtained for both the image and the durability.

The following toner was used as the toner. ・ Styrene-butyl acrylate resin 100 parts ・ 95 parts of magnetite ・ Low molecular weight polypropylene wax 4 parts ・ Alterium complex of ditertiary butylsalicylic acid (Negative charge control agent) 3 parts

The above materials were dispersed and mixed in a Henschel mixer, melt-kneaded in a twin-screw extruder heated to 130 ° C., and the cooled mixture was roughly crushed by a hammer mill.
The coarsely pulverized product was finely pulverized by a jet mill, the obtained finely pulverized product was classified by an air classifier, and the toner particle size distribution was such that the number ratio of particles having a mass average particle diameter of 7.2 μm and 4 μm or less was 17.
A magnetic toner was obtained in which the mass ratio of particles of 5% and 12.7 μm or more was 0.9%. To 100 parts of this toner, 0.9 part of colloidal silica hydrophobized with a silane coupling agent,
And 3 parts of strontium titanate fine particles were externally added and used in a Henschel mixer.

<Physical Properties and Image Measuring Method and Evaluation Method>
The physical properties of the toner and the developing sleeve and the evaluation of the obtained image were carried out by the methods described below. [Measurement Method] (1) Measurement of Arithmetic Average Roughness (Ra) The arithmetic average roughness Ra and the ten-point average roughness Rz were measured using SE-3400 manufactured by Kosaka Laboratory, and the cutoff was 0. At 8 mm, at a specified distance of 8.0 mm, and at a feed rate of 0.5 mm / sec, measurements were made at 3 points in the axial direction × 3 points in the circumferential direction = 9 points, and the average value was taken.

(2) Measurement of volume resistance of coating layer A coating layer having a thickness of 7 to 20 μm was formed on a PET sheet having a thickness of 100 μm, and the standard ASTM (D-991-8) was used.
2) and Japan Rubber Association standard SRIS (2301-1)
969), using a voltage drop type digital ohm meter (manufactured by Kawaguchi Electric Co., Ltd.) provided with electrodes of a four-terminal structure for measuring the volume resistance of conductive rubber and plastic. The measurement environment is 20 to 25 ° C. and 50 to 60 RH%.

(3) Measurement of average particle size of solid particles having a size of 1 μm or more Using a photographic image magnified 500 to 10,000 times by an electron microscope, 300 or more solid particles having a particle size of 0.1 μm or more are randomly extracted, The number average particle size is calculated by measuring the horizontal Feret diameter as a solid particle size by an image processing analyzer Luzex3 manufactured by Nireco Corp. and averaging the particles.

(4) Measurement of average particle size of solid particles of 1 μm or less Using a photographic image magnified 5000 times to 20000 times by an electron microscope, 300 or more particles having a particle size of 0.01 μm or more are randomly extracted, The number average particle diameter is calculated by averaging by measuring the particle diameter of the solid particles with the horizontal Feret diameter by an image processing analyzer Luzex3 manufactured by Nireco Corporation.

(5) Particle size distribution measurement of coating material Laser diffraction type particle size distribution meter manufactured by Nikkiso Co., Ltd. (Microtrack HRA particle size analyzer MODEL No. 9320-X
100) was used to measure the following values. As the center diameter,
When the cumulative curve was calculated assuming that the total volume of the particle group was 100%, the cumulative average diameter at the point where the cumulative curve was 50% was calculated. The standard deviation was obtained from the following formula as a measure of the distribution width of the measured particle size distribution. Standard deviation = (d84% -d16%) / 2, where d84%: particle size at the point where the cumulative curve is 84% d16%: particle size at the point where the cumulative curve is 16%

(6) Measurement of particle size of toner and resin particles The particle size was measured using a Coulter Counter Multisizer II (manufactured by Coulter Co.), and the mass-based mass average diameter calculated from the volume distribution was determined.

(7) Measurement of film thickness (abrasion amount) of coating layer KEYENC is used as a measurement of the abrasion amount (film abrasion) of the coating layer.
A laser size measuring device manufactured by E company was used. Controller LS
Using -5500 and sensor head LS-5040T, the sensor part was separately fixed to the device equipped with the sleeve fixing jig and the sleeve feeding mechanism, and the measurement was performed from the average value of the outer diameter dimension of the sleeve. The measurement was carried out by dividing the lengthwise direction of the sleeve into 30 and measuring 30 points. Further, after rotating the sleeve 90 ° in the circumferential direction, 30 points were further measured, totaling 60 points, and the average value was taken. The outer diameter of the sleeve before applying the surface coating layer was measured in advance, the outer diameter after forming the surface coating layer, and the outer diameter after durable use were measured, and the difference between them was used as the coat film thickness and the scraped amount.

[Evaluation Method] (1) Image Density In a copying machine, the copy image density of a 5 mmφ black circle on a test chart with an image ratio of 5.5% was measured with a reflection densitometer RD918 (manufactured by Macbeth). Done,
The image density was obtained by taking the average value of 5 points. Further, in the LBP, a print image density of 5 mm (2), which was sent by a signal using a character generator and output by a printer, was measured in the same manner and used as the image density.

(2) The reflectance of the solid white image under the fog development suitability condition was measured, and the reflectance of the unused transfer paper was further measured, and the value (the worst value of the reflectance of the solid white image-the unused transfer paper was measured). The maximum value of reflectance) was defined as the fog density. The reflectance was measured by TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.). Here, when the measured value is visually judged, 1.
Below 5 is a level that can hardly be visually confirmed, 2.0
Approximately 3.0 is a level that can be confirmed by looking closely, and a level of 4.0 or more is a level where fogging can be seen at a glance.

(3) Halftone Uniformity (White Streaks, White Bands) The linear and band-shaped streaks that particularly occur in halftones and run in the image advancing direction were evaluated using the following indices. ◯: The image cannot be confirmed at all. B: Slightly confirmed in halftone, but no problem in solid black. Δ: A line is visible in halftone, but is slightly visible in solid black. Δ ×: A difference in shade can be confirmed even in a solid black image, which is a level that is not practical. X: A difference in shade is noticeable in the entire solid black image. Practical level.

(4) Sleeve ghost image After the solid white is flowed during the endurance, a solid black bold character or a hieroglyphic image is placed on the white for one round of the sleeve of the image chart, and an image chart in which the remaining part is halftone is displayed. We evaluated the degree of ghosting of bold characters and hieroglyphic images on halftone. ○: No ghost. ○ △: A level where a slight difference in light and shade can be confirmed but does not pose a problem. Δ: Within a practical level, although a little ghost is noticeable. △ ×: Ghost is noticeable. X: A ghost is conspicuous over two rounds of the sleeve. The above evaluation results are summarized in Table 3.

<Example 2> Paint A-1 used in Example 1
In the dispersion stirring process of No. 2, the peripheral speed of the stirring tool is set to 22 m / se.
Paint A as well as Paint A-1 except that it was changed to c
-2 was prepared and evaluated in the same manner as in Example 1. Paint A
-2 shows the production conditions and physical properties, and Table 3 shows the physical properties of the coating layer and the evaluation results.

Example 3 Resol-type phenolic resin (containing 50% methanol) 300 parts Titanium oxide (average particle size 0.22 μm) 100 parts methanol 200 parts Material of paint A-1 used in Example 1 Is changed as described above, and the peripheral speed of the stirring tool of the stirring / dispersing device is 50 m / sec.
Paint A-same as Paint A-1 except that
3 was prepared and evaluated in the same manner as in Example 1. Paint A-
The production conditions and physical properties of No. 3 are shown in Table 2, and the physical properties and evaluation results of the coating layer are shown in Table 3.

<Comparative Example 1> Paint A used in Example 1
1. Instead of using 1, the coating composition using the same material as A-1 was dispersed in a horizontal sand mill using 1 mm glass beads as a dispersion medium until the center diameter was almost the same as that of coating A-1. Got Evaluations were made in the same manner as in Example 1 except that this paint B-1 was used. Paint B-1
Table 2 shows the production conditions and physical properties of the above, and Table 3 shows the physical properties of the coating layer and the evaluation results.

<Comparative Example 2> Paint A-used in Example 3
Instead of using 3, the coating composition using the same material as A-3 is dispersed by a horizontal sand mill using 1 mm glass beads as a dispersion medium until the center diameter becomes almost the same as that of the coating A-3. Got Evaluations were made in the same manner as in Example 1 except that this paint B-2 was used. Paint B-2
Table 2 shows the production conditions and physical properties of the above, and Table 3 shows the physical properties of the coating layer and the evaluation results.

Example 4 Resol-type phenol resin (containing 50% methanol) 600 parts Carbon black (average particle size 0.039 μm) 100
Part ・ Boron carbide (average particle size 2.33 μm) 40 parts ・ Methanol 400 parts

The material of the coating material A-1 used in Example 1 was changed as described above, and the peripheral speed of the stirrer of the stirrer / disperser was set to 60.
A coating material A-4 was prepared in the same manner as the coating material A-1 except that it was changed to m / sec. Next, the arithmetic mean roughness Ra of 0.2 μm, which is obtained by cutting the aluminum cylindrical tube used in Example 1 and having an outer diameter of 32 mmφ, is not blasted.
Evaluation was performed in the same manner as in Example 1 except that the work of m was used. Table 2 shows the production conditions and physical properties of the coating material A-4, and Table 3 shows the physical properties and evaluation results of the coating layer.

<Comparative Example 3> Paint A-used in Example 4
4 was replaced with a coating composition using the same material as A-4 by a horizontal sand mill using 1 mm glass beads as a dispersion medium until the center diameter was almost the same as that of coating A-4. Got Evaluations were made in the same manner as in Example 4 except that this paint B-3 was used. Paint B-3
Table 2 shows the production conditions and physical properties of the above, and Table 3 shows the physical properties of the coating layer and the evaluation results.

Example 5 Methyl methacrylate-dimethylaminoethyl methacrylate copolymer (molar ratio 90:10, Mw = 12,200, Mn = 5,100, containing 60% toluene) 825 parts Carbon black (average particle size of 0. 039 μm) 10 parts · Graphite (average particle size 2.61 μm) 90 parts · Spherical polyurethane particles (average particle size 4.21 μm) 30
Parts / ethyl acetate 350 parts A coating material was prepared using the above materials.

The above material was used as T.W. K. Using FILMIX (manufactured by Tokushu Kika Kogyo Co., Ltd.), the peripheral speed was 22 m / sec and dispersed for 2 minutes with a brush-shaped stirring tool having a gap of 2 mm from the inside of the container. Further, ethyl acetate was added to adjust the solid content concentration to about 25.
% And then passed through a 350 mesh sieve to paint A
-5 was created. Table 2 shows the manufacturing conditions and physical properties of coating material A-5.

A developing sleeve was prepared in the same manner as in Example 1, except that a cylindrical tube having an outer diameter of 20 mmφ and an arithmetic mean roughness Ra of 0.2 μm obtained by cutting an aluminum cylindrical tube was used as a work. did. Table 2 shows the production conditions and physical properties of the coating material A-5, and Table 3 shows the physical properties of the coating layer of the developing sleeve.

A flange is fitted to this developing sleeve, and L
The sleeve was attached to an EP-82 cartridge of BP-2160 (manufactured by Canon Inc.), and 10,000 durable images were printed under a high temperature and high humidity (H / H) environment of 30 ° C / 80%. The evaluation results are shown in Table 4. Good results were obtained for both the image and the durability. In this evaluation, the toner used was prepared as follows. First, add 0.1 parts to 400 parts of deionized water.
After 225 parts of an M-Na ₃ PO ₄ aqueous solution was added and heated to 60 ° C., the mixture was stirred at 12,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo). 1.0M to this
-Slowly add 35 parts of CaCl ₂ aqueous solution to add Ca ₃ (P
An aqueous medium containing O ₄ ) ₂ was obtained.

The mixture of the following formulation was heated to 60 ° C. and TK
Using a type homomixer (made by Tokushu Kika Kogyo), 12,0
It was uniformly dissolved and dispersed at 00 rpm. Into this, 5 parts of a polymerization initiator 2,2'-azobis (2,4-dimethylvaleronitrile) was dissolved to prepare a polymerizable monomer composition. (Monomer) -Styrene 85 parts-n-butyl acrylate 15 parts-Carbon black (colorant) 7 parts-Salicylic acid metal compound (charge control agent) 2.5 parts-Saturated polyester resin (polar resin) (acid value 14, peak) Molecular weight: 8,000) 5 parts / paraffin wax (release agent) (melting point 60 ° C) 15 parts

Next, the polymerizable monomer composition was put into the aqueous medium prepared as described above, and the mixture was subjected to 10,000 in a TK homomixer at 60 ° C. under N ₂ atmosphere.
The polymerizable monomer composition was granulated by stirring at rpm for 20 minutes. Then, the temperature was raised to 80 ° C. with stirring with a paddle stirring blade, and the reaction was further performed at this temperature for 10 hours to obtain colored suspended particles. Further, after the completion of the polymerization reaction, the residual monomer is distilled off under reduced pressure, and after cooling, hydrochloric acid is added to dissolve calcium phosphate, followed by filtration, washing with water and drying to obtain a mass average diameter of about 6.1 μm and 4. Particle number% of 0 μm or less is 18.6
%, And sharp colored particles (toner particles) having a volume% of particles of 10.1 μm or more of 1.6% were obtained. 100 parts of the colored particles obtained above were treated with a silane coupling agent and silicone oil to obtain hydrophobic colloidal silica 1.
4 parts were externally mixed with a Henschel mixer to obtain a toner.

<Physical Properties and Image Measuring Method and Evaluation Method>
The physical properties of the toner and the developing sleeve and the evaluation of the obtained image were carried out by the methods described below. [Measurement Method] (1) Measurement of Arithmetic Average Roughness (Ra) The arithmetic average roughness Ra and the ten-point average roughness Rz were measured using SE-3400 manufactured by Kosaka Laboratory, and the cutoff was 0. At 8 mm, at a specified distance of 8.0 mm, and at a feed rate of 0.5 mm / sec, measurements were made at 3 points in the axial direction × 3 points in the circumferential direction = 9 points, and the average value was taken.

(2) Measurement of volume resistance of coating layer A coating layer having a thickness of 7 to 20 μm was formed on a PET sheet having a thickness of 100 μm, and the ASTM standard (D-991-8) was used.
2) and Japan Rubber Association standard SRIS (2301-1)
969), using a voltage drop type digital ohm meter (manufactured by Kawaguchi Electric Co., Ltd.) provided with electrodes of a four-terminal structure for measuring the volume resistance of conductive rubber and plastic. The measurement environment is 20 to 25 ° C. and 50 to 60 RH%.

(3) Measurement of average particle size of solid particles having a size of 1 μm or more Using a photographic image magnified 500 to 10,000 times by an electron microscope, 300 or more solid particles having a particle size of 0.1 μm or more are randomly extracted, The number average particle size is calculated by measuring the horizontal Feret diameter as a solid particle size by an image processing analyzer Luzex3 manufactured by Nireco Corp. and averaging the particles.

(4) Measurement of average particle diameter of solid particles of 1 μm or less Using a photographic image magnified 5000 to 20000 times by an electron microscope, 300 or more particles having a particle diameter of 0.01 μm or more are randomly extracted, The number average particle diameter is calculated by averaging by measuring the particle diameter of the solid particles with the horizontal Feret diameter by an image processing analyzer Luzex3 manufactured by Nireco Corporation.

(5) Particle size distribution measurement of coating material Laser diffraction type particle size distribution meter manufactured by Nikkiso Co., Ltd. (Microtrack HRA particle size analyzer MODEL No. 9320-X
100) was used to measure the following values. As the center diameter,
When the cumulative curve was calculated assuming that the total volume of the particle group was 100%, the cumulative average diameter at the point where the cumulative curve was 50% was calculated. The standard deviation was obtained from the following formula as a measure of the distribution width of the measured particle size distribution. Standard deviation = (d84% -d16%) / 2, where d84%: particle size at the point where the cumulative curve is 84% d16%: particle size at the point where the cumulative curve is 16%

(6) Measurement of Toner and Resin Particle Size Particles were measured using a Coulter Counter Multisizer II (manufactured by Beckman Coulter, Inc.), and the mass-based mass average diameter calculated from the volume distribution was determined.

(7) Measurement of coating layer thickness (abrasion amount) KEYENC is used as a measurement of the coating layer abrasion amount (film abrasion).
A laser size measuring device manufactured by E company was used. Controller LS
Using -5500 and sensor head LS-5040T, the sensor part was separately fixed to the device equipped with the sleeve fixing jig and the sleeve feeding mechanism, and the measurement was performed from the average value of the outer diameter dimension of the sleeve. The measurement was carried out by dividing the lengthwise direction of the sleeve into 30 and measuring 30 points. Further, after rotating the sleeve 90 ° in the circumferential direction, 30 points were further measured, totaling 60 points, and the average value was taken. The outer diameter of the sleeve before applying the surface coating layer was measured in advance, the outer diameter after forming the surface coating layer, and the outer diameter after durable use were measured, and the difference between them was used as the coat film thickness and the scraped amount.

[Evaluation Method] (1) Image Density In the copying machine, the copy image density of a 5 mmφ black circle on the test chart with an image ratio of 5.5% was measured by a reflection densitometer RD918 (manufactured by Macbeth). Done,
The image density was obtained by taking the average value of 5 points. Further, in the LBP, a print image density of 5 mm (2), which was sent by a signal using a character generator and output by a printer, was measured in the same manner and used as the image density.

(2) The reflectance of the solid white image under the fog development suitability condition was measured, and the reflectance of the unused transfer paper was further measured (the worst value of the reflectance of the solid white image-the unused transfer paper). The maximum value of reflectance) was defined as the fog density. The reflectance was measured by TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.). Here, when the measured value is visually judged, 1.
Below 5 is a level that can hardly be visually confirmed, 2.0
Approximately 3.0 is a level that can be confirmed by looking closely, and a level of 4.0 or more is a level where fogging can be seen at a glance.

(3) Halftone uniformity (white streak, white band) Particularly, a linear or band-shaped streak generated in a halftone and running in the image advancing direction was evaluated by the following index. ◯: The image cannot be confirmed at all. B: Slightly confirmed in halftone, but no problem in solid black. Δ: A line is visible in halftone, but is slightly visible in solid black. Δ ×: A difference in shade can be confirmed even in a solid black image, which is a level that is not practical. X: A difference in shade is noticeable in the entire solid black image. Practical level.

(4) Sleeve Ghost Image After running a solid white color during the endurance, a solid black bold character or hieroglyphic image is placed on the white for one round of the sleeve of the image chart, and the remaining part is a halftone image chart. Using halftone, we evaluated the degree of ghosting in bold letters and hieroglyphic images. ○: No ghost. ○ △: A level where a slight difference in light and shade can be confirmed but does not pose a problem. Δ: Within a practical level, although a little ghost is noticeable. △ ×: Ghost is noticeable. X: A ghost is conspicuous over two rounds of the sleeve.

(5) Blade scratch O: Although scratches are not visible at first glance, there are slight scratches when viewed closely. ○ △: There are many minor scratches, but the image is not affected. Δ: There are several scratches that are slightly conspicuous, and slight black streaks occur in the image, but they are hardly noticeable. Δ ×: Conspicuous scratches are generated at several places, and a slightly conspicuous black streak appears on the image. X: Many very conspicuous scratches are generated and appear as remarkable black streaks on the image.

<Example 6> Paint A-5 used in Example 5
In the dispersion and stirring process of No. 4, the peripheral speed of the stirring tool is set to 40 m / se.
Coating A-6 was prepared in the same manner as Coating A-5, except that the average particle size of graphite in the coating composition was changed to 7.32 μm, and the same evaluation as in Example 5 was carried out. went. Table 2 shows the production conditions and physical properties of the coating material A-6, and Table 4 shows the physical properties of the coating layer and the evaluation results.

[0205]

[0206] A coating material A-7 was prepared in the same manner as the coating material A-5 except that the material of the coating material A-5 used in Example 5 was changed as described above, and the same evaluation as in Example 5 was performed. . Table 2 shows the production conditions and physical properties of the coating material A-7, and Table 4 shows the physical properties and evaluation results of the coating layer.
Shown in.

<Comparative Example 4> Paint A-used in Example 5
Instead of using No. 5, a coating composition using the same material as A-5 was dispersed in a horizontal sand mill using 1 mm glass beads as a dispersion medium until the center diameter was almost the same as that of coating A-5, and coating B-4 Got Evaluations were made in the same manner as in Example 5 except that this paint B-4 was used. Paint B-4
Table 2 shows the production conditions and physical properties of and the physical properties of the coating layer and the evaluation results are shown in Table 4.

<Comparative Example 5> Paint A used in Example 6
6 was replaced with a coating composition using the same material as A-6 by a horizontal sand mill using 1 mm glass beads as a dispersion medium until the center diameter was almost the same as that of coating A-6. Got Evaluations were made in the same manner as in Example 5 except that this paint B-5 was used. Paint B-5
Table 2 shows the production conditions and physical properties of and the physical properties of the coating layer and the evaluation results are shown in Table 4.

<Comparative Example 6> Paint A used in Example 7
Instead of using No. 7, a coating composition using the same material as A-7 was dispersed in a horizontal sand mill using 1 mm glass beads as a dispersion medium until the center diameter was almost the same as that of the coating A-7. Got Evaluations were made in the same manner as in Example 5 except that this paint B-6 was used. Paint B-6
Table 2 shows the production conditions and physical properties of and the physical properties of the coating layer and the evaluation results are shown in Table 4.

[0210]

A coating material was prepared using the above materials. The above material was applied to K. Filmix (made by Tokushu Kika Kogyo Co., Ltd.)
And a peripheral speed of 40 m / sec was dispersed for 2 minutes with a brush-shaped stirring tool having a gap of 2 mm from the inside of the container. After adding methanol to make the solid content concentration about 34%, 350
A paint A-8 was prepared by passing through a sieve of mesh. Table 2 shows the manufacturing conditions and physical properties of coating material A-8.

A developing sleeve was prepared in the same manner as in Example 1 except that a cylindrical tube having an outer diameter of 20 mmφ and an arithmetic mean roughness Ra of 0.2 μm obtained by cutting an aluminum cylindrical tube was used as a work. did. Table 2 shows the production conditions and physical properties of the coating material A-8, and Table 3 shows the physical properties of the coating layer of the developing sleeve.

A flange is fitted to this developing sleeve, and L
The sleeve was attached to an EP-W cartridge of BP-930 (manufactured by Canon Inc.), and as an elastic regulation blade, silicon rubber in which colloidal silica was dispersed in silicon rubber was cut like a blade and attached to a washer. . This cartridge is used at 24 ° C using LBP-930.
Durability images were printed on 20,000 sheets under a normal temperature and low humidity (N / L) environment of / 10%. The evaluation results are shown in Table 5. Good results were obtained for both the image and the durability.

In this evaluation, the toner used was prepared as follows.

The above materials were premixed with a Henschel mixer, and then melt-kneaded using a twin-screw extruder set at 130 ° C. After cooling the kneaded product, coarse pulverization was performed using a speed mill, and further fine pulverization was performed using a jet mill. This finely pulverized product was classified using an elbow jet classifier, and the particle size distribution of the toner was such that the mass average particle size was 7.3 μm.
m, the number ratio of particles of 4 μm or less is 18.3%, 12.
A magnetic toner having a mass ratio of particles of 7 μm or more of 1.3% was obtained. For this toner, hydrophobic colloidal silica 1.2 treated with a silane coupling agent and silicone oil was used.
Part of the toner was externally mixed with a Henschel mixer to obtain a toner.

<Physical Properties and Image Measuring Method and Evaluation Method>
The physical properties of the toner and the developing sleeve and the evaluation of the obtained image were performed by the methods described below. [Measurement Method] (1) Measurement of Arithmetic Average Roughness (Ra) The arithmetic average roughness Ra and the ten-point average roughness Rz were measured using SE-3400 manufactured by Kosaka Laboratory, and the cutoff was 0. At 8 mm, at a specified distance of 8.0 mm, and at a feed rate of 0.5 mm / sec, measurements were made at 3 points in the axial direction × 3 points in the circumferential direction = 9 points, and the average value was taken.

(2) Measurement of volume resistance of coating layer A coating layer having a thickness of 7 to 20 μm was formed on a PET sheet having a thickness of 100 μm, and the standard ASTM (D-991-8) was used.
2) and Japan Rubber Association standard SRIS (2301-1)
969), using a voltage drop type digital ohm meter (manufactured by Kawaguchi Electric Co., Ltd.) provided with electrodes of a four-terminal structure for measuring the volume resistance of conductive rubber and plastic. The measurement environment is 20 to 25 ° C. and 50 to 60 RH%.

(3) Measurement of average particle size of solid particles of 1 μm or more Using a photographic image magnified 500 to 10,000 times by an electron microscope, 300 or more solid particles of 0.1 μm or more in particle size are randomly extracted. Then, a horizontal Feret diameter is measured as a solid particle diameter by an image processing analyzer Luzex3 manufactured by Nireco Corporation, and the number average particle diameter is calculated by averaging.

(4) Measurement of average particle size of solid particles of 1 μm or less Using a photographic image magnified 5000 to 20000 times by an electron microscope, 300 or more particles having a particle size of 0.01 μm or more are randomly extracted, The number average particle diameter is calculated by averaging by measuring the particle diameter of the solid particles with the horizontal Feret diameter by an image processing analyzer Luzex3 manufactured by Nireco Corporation.

(5) Particle size distribution measurement of coating material Laser diffraction type particle size distribution meter manufactured by Nikkiso Co., Ltd. (Microtrack HRA particle size analyzer MODEL No. 9320-X
100) was used to measure the following values. As the center diameter,
When the cumulative curve was calculated assuming that the total volume of the particle group was 100%, the cumulative average diameter at the point where the cumulative curve was 50% was calculated. The standard deviation was obtained from the following formula as a measure of the distribution width of the measured particle size distribution. Standard deviation = (d84% -d16%) / 2, where d84%: particle size at the point where the cumulative curve is 84% d16%: particle size at the point where the cumulative curve is 16%

(6) Measurement of particle size of toner and resin particles The particle size was measured using a Coulter Counter Multisizer II (manufactured by Coulter Co.), and the mass-based mass average diameter calculated from the volume distribution was determined.

(7) Measurement of coating layer thickness (abrasion amount) KEYENC is used to measure the abrasion amount (abrasion amount) of the coating layer.
A laser size measuring device manufactured by E company was used. Controller LS
Using -5500 and sensor head LS-5040T, the sensor part was separately fixed to the device equipped with the sleeve fixing jig and the sleeve feeding mechanism, and the measurement was performed from the average value of the outer diameter dimension of the sleeve. The measurement was carried out by dividing the lengthwise direction of the sleeve into 30 and measuring 30 points. Further, after rotating the sleeve 90 ° in the circumferential direction, 30 points were further measured, totaling 60 points, and the average value was taken. The outer diameter of the sleeve before applying the surface coating layer was measured in advance, the outer diameter after forming the surface coating layer, and the outer diameter after durable use were measured, and the difference between them was used as the coat film thickness and the scraped amount.

[Evaluation Method] (1) Image Density In a copying machine, a copy image density of a 5 mmφ black circle on a test chart with an image ratio of 5.5% was measured by a reflection densitometer RD.
The reflection density was measured by 918 (manufactured by Macbeth), and the average value of 5 points was taken as the image density. Further, in the LBP, a print image density of 5 mm (2), which was sent by a signal using a character generator and output by a printer, was measured in the same manner and used as the image density.

(2) The reflectance of the solid white image under the fog development suitability condition was measured, and the reflectance of the unused transfer paper was further measured (the worst value of the reflectance of the solid white image-the unused transfer paper The maximum value of reflectance) was defined as the fog density. The reflectance was measured by TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.). Here, when the measured value is visually judged, 1.
Below 5 is a level that can hardly be visually confirmed, 2.0
Approximately 3.0 is a level that can be confirmed by looking closely, and a level of 4.0 or more is a level where fogging can be seen at a glance.

(3) Halftone Uniformity (White Streaks, White Bands) Especially, linear or band-shaped streaks that occur in the halftone and run in the image advancing direction were evaluated by the following indexes. ◯: The image cannot be confirmed at all. B: Slightly confirmed in halftone, but no problem in solid black. Δ: A line is visible in halftone, but is slightly visible in solid black. Δ ×: A difference in shade can be confirmed even in a solid black image, which is a level that is not practical. X: A difference in shade is noticeable in the entire solid black image. Practical level.

(4) Sleeve ghost image After the solid white is flown during the endurance, a solid black bold character or a hieroglyphic image is placed on the white for one round of the sleeve of the image chart, and the rest is halftone image chart. It was evaluated by how much ghost of bold characters and hieroglyphic images were generated on the halftone. ○: No ghost. ○ △: A level where a slight difference in light and shade can be confirmed but does not pose a problem. Δ: Within a practical level, although a little ghost is noticeable. △ ×: Ghost is noticeable. X: A ghost is conspicuous over two rounds of the sleeve.

(5) Blade scratch O: No scratch can be seen at first sight, but there is a slight scratch when viewed closely. ○ △: There are many minor scratches, but the image is not affected. Δ: There are several scratches that are slightly conspicuous, and slight black streaks occur in the image, but they are hardly noticeable. Δ ×: Conspicuous scratches are generated at several places, and a slightly conspicuous black streak appears on the image. X: Many very conspicuous scratches are generated and appear as remarkable black streaks on the image.

<Example 9> Coating material A-prepared in Example 8
The average particle size of boron carbide in the coating composition used in No. 8 was 6.6.
A coating material A-9 was prepared in the same manner as the coating material A-8 except that the coating material was changed to have a thickness of 5 μm, and was evaluated in the same manner as in Example 8. Table 2 shows the production conditions and physical properties of the coating material A-9, and Table 5 shows the physical properties of the coating layer and the evaluation results.

<Example 10> Paint A prepared in Example 8
The average particle size of boron carbide in the coating composition used in -8 is 1
Paint A-8 except that it was changed to 3.1 μm
A coating material A-10 was prepared in the same manner as in, and evaluated in the same manner as in Example 8. Table 2 shows manufacturing conditions and physical properties of the coating material A-10, and Table 5 shows physical properties of the coating layer and evaluation results.

<Comparative Example 7> Paint A used in Example 8
8 was replaced with a coating composition using the same material as A-8 by a horizontal sand mill using 1 mm glass beads as a dispersion medium until the center diameter was almost the same as that of coating A-8. Got Evaluations were made in the same manner as in Example 8 except that this paint B-7 was used. Paint B-7
Table 2 shows the production conditions and physical properties of and the physical properties and evaluation results of the coating layer are shown in Table 5.

<Comparative Example 8> Paint A-used in Example 9
Instead of using No. 9, a coating composition using the same material as A-9 was dispersed by a horizontal sand mill using 1 mm glass beads as a dispersion medium until the center diameter was almost the same as that of the coating A-9. Got Evaluations were made in the same manner as in Example 8 except that this paint B-8 was used. Paint B-8
Table 2 shows the production conditions and physical properties of and the physical properties and evaluation results of the coating layer are shown in Table 5.

<Comparative Example 9> Paint A used in Example 10
Instead of using -10, a coating composition using the same material as A-10 is dispersed by a horizontal sand mill using 1 mm glass beads as a dispersion medium until the center diameter becomes almost the same as that of coating A-10, and coating B- Got 9. Evaluations were made in the same manner as in Example 8 except that this paint B-9 was used. Table 2 shows the production conditions and physical properties of the coating material B-9, and Table 5 shows the physical properties of the coating layer and the evaluation results.

[0233]

A coating material was prepared using the above materials. The above material was added to T.I. K. Filmix (made by Tokushu Kika Kogyo Co., Ltd.)
And a peripheral speed of 30 m / sec for 2 minutes with a brush-shaped stirring tool having a gap of 2 mm from the inside of the container. After adding methanol to make the solid content concentration about 34%, 350
A paint A-11 was prepared by passing through a sieve of mesh.
Table 2 shows the manufacturing conditions and physical properties of coating material A-11.

A developing sleeve was prepared in the same manner as in Example 1 except that a cylindrical tube having an outer diameter of 32 mmφ and an arithmetic mean roughness Ra of 0.2 μm obtained by cutting an aluminum cylindrical tube was used as a work. did. Table 2 shows the production conditions and physical properties of the coating material A-8, and Table 3 shows the physical properties of the coating layer of the developing sleeve.

A magnet is attached to the developing sleeve, and a stainless steel flange is fitted to the developing sleeve.
It can be installed in the developing device of LC-1000. Using the following cyan toner, normal temperature and normal humidity (N /
N) Durability images of 200,000 sheets were printed under the environment. The following developer was used. -Polyester resin 100 parts-Phthalocyanine pigment 6 parts-Ditertiary butyl salicylic acid AI complex 4 parts

5 parts of the polyester resin and 6 parts of the phthalocyanine pigment are sufficiently kneaded in advance by using a three-roll to prepare a masterbatch. After thoroughly kneading the crushed masterbatch, the remaining polyester resin, and the AI complex of ditertiary butylsalicylic acid using a Henschel mixer, melt kneading with a twin-screw extruder heated to 110 ° C and hammering the cooled mixture. Coarsely pulverized with a mill. The coarsely pulverized product is finely pulverized by a jet mill, and the finely pulverized product is classified by using an elbow jet classifier, and the toner particle size distribution is such that the number ratio of particles having a mass average particle diameter of 7.6 μm and 4 μm or less is 9. Cyan toner was obtained in which the mass ratio of particles of 3% and 12.7 μm or more was 1.7%. To this toner, 1.6 parts of hydrophobic colloidal silica treated with a silane coupling agent and silicone oil was externally added and mixed with a Henschel mixer to obtain a toner.

As the carrier, a ferrite carrier coated with a silicone resin and having an average particle size of 40 μm was used. The cyan toner T and the carrier C were mixed so as to have a T / C ratio of 7% to obtain a starting agent. The evaluation results are shown in Table 6. Good results were obtained for both the image and the durability.

<Physical Properties and Image Measuring Method and Evaluation Method>
The physical properties of the toner and the developing sleeve and the evaluation of the obtained image were performed by the methods described below. [Measurement Method] (1) Measurement of Arithmetic Average Roughness (Ra) The arithmetic average roughness Ra and the ten-point average roughness Rz were measured using SE-3400 manufactured by Kosaka Laboratory, and the cutoff was 0. At 8 mm, at a specified distance of 8.0 mm, and at a feed rate of 0.5 mm / sec, measurements were made at 3 points in the axial direction × 3 points in the circumferential direction = 9 points, and the average value was taken.

(2) Measurement of volume resistance of coating layer A coating layer having a thickness of 7 to 20 μm was formed on a PET sheet having a thickness of 100 μm, and the ASTM standard (D-991-8) was used.
2) and Japan Rubber Association standard SRIS (2301-1)
969), using a voltage drop type digital ohm meter (manufactured by Kawaguchi Electric Co., Ltd.) provided with electrodes of a four-terminal structure for measuring the volume resistance of conductive rubber and plastic. The measurement environment is 20 to 25 ° C. and 50 to 60 RH%.

(3) Measurement of average particle size of solid particles of 1 μm or more Using a photographic image magnified 500 to 10,000 times by an electron microscope, 300 or more solid particles of 0.1 μm or more in particle size are randomly extracted. Then, a horizontal Feret diameter is measured as a solid particle diameter by an image processing analyzer Luzex3 manufactured by Nireco Corporation, and the number average particle diameter is calculated by averaging.

(4) Measurement of average particle size of solid particles of 1 μm or less Using a photographic image magnified 5,000 to 20,000 times by an electron microscope, 300 particles having a particle size of 0.01 μm or more are randomly selected. The particles are extracted as described above, and the horizontal Feret diameter is measured as the particle diameter of solid particles by an image processing analyzer Luzex3 manufactured by Nireco Corp., and the number average particle diameter is calculated by averaging.

(5) Particle size distribution measurement of coating material Laser diffraction type particle size distribution meter manufactured by Nikkiso Co., Ltd. (Microtrack HRA particle size analyzer MODEL No. 9320-X
100) was used to measure the following values. As the center diameter,
When the cumulative curve was calculated assuming that the total volume of the particle group was 100%, the cumulative average diameter at the point where the cumulative curve was 50% was calculated. The standard deviation was obtained from the following formula as a measure of the distribution width of the measured particle size distribution. Standard deviation = (d84% -d16%) / 2, where d84%: particle size at the point where the cumulative curve is 84% d16%: particle size at the point where the cumulative curve is 16%

(6) Measurement of particle size of toner and resin particles The particle size was measured using Multisizer II (manufactured by Beckman Coulter, Inc.) of Coulter Counter, and the mass-based mass average diameter calculated from the volume distribution was determined.

(7) Measurement of coating layer thickness (abrasion amount) KEYENC is used to measure the abrasion amount (abrasion amount) of the coating layer.
A laser size measuring device manufactured by E company was used. Controller LS
Using -5500 and sensor head LS-5040T, the sensor part was separately fixed to the device equipped with the sleeve fixing jig and the sleeve feeding mechanism, and the measurement was performed from the average value of the outer diameter dimension of the sleeve. The measurement was carried out by dividing the lengthwise direction of the sleeve into 30 and measuring 30 points. Further, after rotating the sleeve 90 ° in the circumferential direction, 30 points were further measured, totaling 60 points, and the average value was taken. The outer diameter of the sleeve before applying the surface coating layer was measured in advance, the outer diameter after forming the surface coating layer, and the outer diameter after durable use were measured, and the difference between them was used as the coat film thickness and the scraped amount.

[Evaluation Method] (1) Image Density In a copying machine, the copy image density of a 5 mmφ black circle on a test chart with an image ratio of 5.5% was measured by a reflection densitometer RD.
The reflection density was measured by 918 (manufactured by Macbeth), and the average value of 5 points was taken as the image density. Further, in the LBP, a print image density of 5 mm (2), which was sent by a signal using a character generator and output by a printer, was measured in the same manner and used as the image density.

(2) After the sleeve contamination durability test, the developer on the developing sleeve was blown off with air and then observed with a microscope. A: It is invisible to the naked eye, but it can be seen that it is slightly contaminated under a microscope. B: Not visible to the naked eye yet, but when viewed under a microscope, some contamination is seen. C: Contamination is visible to the naked eye.

(3) Amount of Transported Developer (M / S) The developer carried on the developing sleeve is sucked and collected by the metal cylindrical tube and the cylindrical filter, and the amount of developer M collected by the cylindrical filter is M. Then, the developer mass M / S per unit area was calculated from the area S in which the developer was sucked, and was defined as the developer transport amount (M / S).

<Example 12> Paint A used in Example 11
In the dispersion stirring process of -11, the peripheral speed of the stirring tool is 60 m.
The coating material A-12 was prepared in the same manner as the coating material A-11 except that it was changed to / sec, and evaluated in the same manner as in Example 11. Table 2 shows the production conditions and physical properties of the coating material A-12, and Table 6 shows the physical properties of the coating layer and the evaluation results.

Comparative Example 10 Instead of using the paint A-11 used in Example 11, a paint composition using the same material as A-11 was applied to a paint A using a horizontal sand mill using 1 mm glass beads as a dispersion medium. A paint B-10 was obtained by dispersing until the center diameter was almost the same as that of -11. This paint B-1
Evaluations were made in the same manner as in Example 11 except that 0 was used. Table 2 shows the production conditions and physical properties of the coating material B-10, and Table 6 shows the physical properties and evaluation results of the coating layer.

[0251]

A coating material was prepared using the above materials. The above material was added to T.I. K. Filmix (made by Tokushu Kika Kogyo Co., Ltd.)
And a peripheral speed of 30 m / sec for 2 minutes with a brush-shaped stirring tool having a gap of 2 mm from the inside of the container. After adding methanol to make the solid content concentration about 38%, 350
A paint A-13 was prepared by passing it through a mesh sieve.
Table 2 shows the manufacturing conditions and physical properties of Paint A-13.

Magnetic properties for charging were the same as in Example 1 except that a cylindrical tube having an outer diameter of 16 mmφ and an arithmetic mean roughness Ra of 0.2 μm obtained by cutting an aluminum cylindrical tube was used as a work. A particle transfer sleeve was created. Paint A
The production conditions and physical properties of -13 are shown in Table 2, and the physical properties of the coating layer of this developing sleeve are shown in Table 3. A magnet is attached to the charging magnetic particle carrying sleeve, a stainless steel flange is fitted, and a digital copying machine using a laser beam as an electrophotographic apparatus (Canon: GP)
55).

The apparatus is roughly equipped with a corona charger as the primary charging means of the photoconductor, a one-component developing device adopting the one-component jumping developing method as the developing means, a corona charging device as the transfer means, a blade cleaning means, A pre-charging exposure unit is provided. Further, the photoconductor, the primary charging charger, and the cleaning means are integrated units (process cartridges). Process speed is 150
mm / sec. This digital copying machine was modified as follows.

First, the process speed is set to 200 mm / s.
It was converted to ec. The development part was modified from one-component jumping development to use a two-component developer. Further, as the primary charging means, the previously-produced charging magnetic particle carrying sleeve is arranged to form the charging magnetic brush. The minimum gap between the charging magnetic particle conveying sleeve and the photoconductor was set to 0.5 mm. Also, the developing bias is
Peak-to-peak voltage (Vpp) of 100 for DC component of -500V
A rectangular wave of 0 V and a frequency of 3 kHz is superimposed.

Further, the transfer means using the corona charger was changed to the roller transfer system, and the pre-charging exposure means was removed. Further, the cleaning blade was removed to obtain a cleanerless copying machine. FIG. 11 shows a schematic diagram. 1 in the figure
01 is a fixing device, 102 is a charger, 103 is magnetic particles for charging, 104 is a conductive sleeve containing a magnet roller,
Reference numeral 105 is a photoconductor, 106 is exposure light, 107 is a developing sleeve, 108 is a developing device, 109 and 110 are stirring screws, 111 is a developer, 112 is a paper conveyance guide, 113 is transfer paper, 114 is a transfer roller, and 115 is A paper carrying belt, 116 is a process cartridge, and 117 is a developing cartridge.

Using this digital copying machine, the magnetic particles are mounted on a charger so that the coating density is 180 dg / m ^2, and the photoreceptor is mounted. In order to mount it at 180 dg / m ² , a minimum amount of magnetic particles of about 30 g is required. The magnetic brush charger is rotated in the opposite direction at the contact portion with the photoconductor. At this time, the peripheral speed of rotation of the charger is 240 mm / sec.

The bias applied to the charging member was a direct current voltage of −700 V and a rectangular wave oscillating voltage of 1 kHz and 700 Vpp. The developing bias is -500V.
A rectangular wave AC voltage of 1000 Vpp / 3 kHz was superposed on the DC voltage of No. 3, and a character image (A4) with an image ratio of 3% was formed under the conditions of a temperature of 15 ° C. and a relative humidity of 10%. The carrier carrying the thus-produced charging magnetic particles was incorporated into the printer having the above-mentioned configuration. Even if the photoconductor passed through the contact nip once, the photoconductor surface potential, which was initially 0V, was charged to -680V, and good chargeability could be obtained. Further, at this time, even if pinholes were formed on the photoconductor, no leak occurred, and the conductive particles forming the charging member were not developed on the photoconductor, and a good image was obtained. .

The durability test is conducted as follows. Character image (A4) with 3% image ratio is rotated at a peripheral speed of 300 mm / s.
Under the condition of ec, 60,000 sheets are copied in 1200 cycles in 50 sheets intermittent mode, and the same evaluation as the initial stage is performed. At this time, regarding the non-image forming portion, during continuous sheet feeding, at the time of charging (before rotation) before the first image on the first sheet can be formed, during image formation (sheet interval), and image formation on the 50th sheet. At the time of charging the photoconductor (after rotation) after the end, by applying a DC voltage of -700 V and a rectangular wave AC voltage of 1 kHz and 500 Vpp, the toner mixed in the charging magnetic brush is charged while the photoconductor is charged. It is moved onto the photoconductor and collected at the development area.

The following developing agents were used for evaluation.・ Polyester resin 100 parts ・ Metal-containing azo dye 2 parts ・ Low molecular weight polypropylene 3 parts ・ Carbon black 5 parts

The above materials were dry-mixed and then kneaded by a twin-screw kneading extruder set at 150 ° C. The obtained kneaded product was cooled, finely pulverized by an air flow type pulverizer, and then air-classified to obtain a toner composition having a controlled particle size distribution. To the toner composition, 1.6% by mass of hydrophobized titanium oxide was added to prepare a toner having a mass average particle size of 7.1 μm. A developer was prepared by mixing 6 parts of toner with 100 parts of nickel zinc ferrite having an average particle size of 50 μm and coated with a silicone resin.

The following were used as the magnetic particles for charging. Fe ₂ O ₃ 53 mol%, CuO ₂ 4 mol%, ZnO ₂
Phosphorus (0.05 parts) was added to 100 parts (3 mol%), and the mixture was pulverized and mixed with a ball mill, and a dispersant, a binder and water were added to form a slurry, and granulation was performed with a spray dryer. After appropriately classifying, baking was performed at 1100 ° C. in the atmosphere. The obtained ferrite was crushed and then classified to obtain ferrite particles having an average particle size of 50 μm. The volume resistance of the ferrite particles is 1 × 10 ⁷ Ω · cm.
Details of the characteristics are summarized in Table 1. Also, the shape is a very good spherical shape. When the durability and the image of the charging magnetic particle carrying sleeve were evaluated using the above-described structure, good results were obtained. The evaluation results are shown in Table 7.

<Physical Properties and Image Measuring Method and Evaluation Method>
The measurement of physical properties of the charging magnetic particle carrying sleeve and the evaluation of the obtained image were carried out by the following methods. [Measurement Method] (1) Measurement of Arithmetic Average Roughness (Ra) The arithmetic average roughness Ra and the ten-point average roughness Rz were measured using SE-3400 manufactured by Kosaka Laboratory, and the cutoff was 0. At 8 mm, at a specified distance of 8.0 mm, and at a feed rate of 0.5 mm / sec, measurements were made at 3 points in the axial direction × 3 points in the circumferential direction = 9 points, and the average value was taken.

(2) Measurement of volume resistance of coating layer A coating layer having a thickness of 7 to 20 μm was formed on a PET sheet having a thickness of 100 μm, and the ASTM standard (D-991-8) was used.
2) and Japan Rubber Association standard SRIS (2301-1)
969), using a voltage drop type digital ohm meter (manufactured by Kawaguchi Electric Co., Ltd.) provided with electrodes of a four-terminal structure for measuring the volume resistance of conductive rubber and plastic. The measurement environment is 20 to 25 ° C. and 50 to 60 RH%.

(3) Measurement of average particle size of solid particles having a size of 1 μm or more Using a photographic image magnified 500 to 10,000 times by an electron microscope, 300 or more solid particles having a particle size of 0.1 μm or more are randomly extracted. Then, a horizontal Feret diameter is measured as a solid particle diameter by an image processing analyzer Luzex3 manufactured by Nireco Corporation, and the number average particle diameter is calculated by averaging.

(4) Measurement of average particle size of solid particles of 1 μm or less Using a photographic image magnified 5000 to 20,000 times by an electron microscope, 300 or more particles having a particle size of 0.01 μm or more are randomly extracted. Then, the particle size of the solid particles is measured with the horizontal Feret diameter by the image processing analyzer Luzex3 manufactured by Nireco Corporation, and the number average particle diameter is calculated by averaging.

(5) Particle size distribution measurement of coating material Laser diffraction type particle size distribution meter manufactured by Nikkiso Co., Ltd. (Microtrack HRA particle size analyzer MODEL No. 9320-X
100) was used to measure the following values. As the center diameter,
When the cumulative curve was calculated assuming that the total volume of the particle group was 100%, the cumulative average diameter at the point where the cumulative curve was 50% was calculated. The standard deviation was obtained from the following formula as a measure of the distribution width of the measured particle size distribution. Standard deviation = (d84% -d16%) / 2, where d84%: particle size at the point where the cumulative curve is 84% d16%: particle size at the point where the cumulative curve is 16%

(6) Measurement of particle size of toner and resin particles The particle size was measured using Multisizer II (manufactured by Beckman Coulter, Inc.) of Coulter Counter, and the mass-based mass average diameter calculated from the volume distribution was determined.

(7) Measurement of coating layer thickness (abrasion amount) KEYENC is used as a measurement of the coating layer abrasion amount (film abrasion).
A laser size measuring device manufactured by E company was used. Controller LS
Using -5500 and sensor head LS-5040T, the sensor part was separately fixed to the device equipped with the sleeve fixing jig and the sleeve feeding mechanism, and the measurement was performed from the average value of the outer diameter dimension of the sleeve. The measurement was carried out by dividing the lengthwise direction of the sleeve into 30 and measuring 30 points. Further, after rotating the sleeve 90 ° in the circumferential direction, 30 points were further measured, totaling 60 points, and the average value was taken. The outer diameter of the sleeve before applying the surface coating layer was measured in advance, the outer diameter after forming the surface coating layer, and the outer diameter after durable use were measured, and the difference between them was used as the coat film thickness and the scraped amount.

[Evaluation Method] (1) Image Density In a copying machine, the copy image density of a 5 mmφ black circle on a test chart with an image ratio of 5.5% was measured with a reflection densitometer RD.
The reflection density was measured by 918 (manufactured by Macbeth), and the average value of 5 points was taken as the image density. Further, in the LBP, a print image density of 5 mm (2), which was sent by a signal using a character generator and output by a printer, was measured in the same manner and used as the image density.

(2) Transport amount of magnetic particles (M / S) The magnetic particles carried on the magnetic particle transport sleeve are suction-collected by the metal cylindrical tube and the cylindrical filter, and the magnetic particles collected by the cylindrical filter are collected. The magnetic particle mass M / S per unit area was calculated from the amount M and the area S in which the magnetic particles were sucked, and was defined as the magnetic particle transport amount (M / S).

<Example 14> Paint A used in Example 13
In the dispersion stirring process of -13, the peripheral speed of the stirring tool is 60 m.
The coating material A-14 was prepared in the same manner as the coating material A-13 except that it was changed to / sec, and the same evaluation as in Example 13 was performed. Table 2 shows the production conditions and physical properties of the coating material A-14, and Table 7 shows the physical properties of the coating layer and the evaluation results.

Comparative Example 11 Instead of using the paint A-14 used in Example 14, a paint composition using the same material as A-14 was used to paint A on a horizontal sand mill using 1 mm glass beads as a dispersion medium. A paint B-11 was obtained by dispersing until the center diameter was almost the same as that of -14. This paint B-1
Evaluation was performed in the same manner as in Example 14 except that 1 was used. Table 2 shows the production conditions and physical properties of the coating material B-11, and Table 7 shows the physical properties of the coating layer and the evaluation results.

[0274]

[0275]

[0276]

[0277]

[0278]

[0279]

[0280]

[0281]

[0282]

[0283]

[0284]

[0285]

[0286]

[0287]

According to the present invention as described above, in the step of stirring and dispersing the coating composition forming the surface of the coating layer, the coating composition to be stirred is used as a stirring device used for the stirring and dispersing. A stirring device having a container having a circular cross section capable of being rotated, a rotating shaft provided at the center of the container, and a stirring tool that rotates at a high speed and has a radius reaching the vicinity of the inner peripheral surface of the container attached to the rotating shaft. Use the agitator with a peripheral speed of 20 m
/ Sec or more to drive the coating composition by a centrifugal force to press the coating composition to the inner surface of the container and to rotate the coating composition in the form of a hollow thin film to form a coating by dry coating of the coating composition stirred and dispersed, whereby the coating composition Solid particles having a specific gravity difference with the coating resin, solid particles having large aggregability, large molecular weight coating resin, does not cause aggregation or separation of particles in the coating layer even if it contains conductive fine particles, etc., It is possible to form a uniform surface coating layer on the surface of the coating layer, in which coating defects such as protrusions, coating unevenness, and appearance of the base material do not occur.

Further, it is possible to form a coating layer surface having a desired surface shape and a uniform dispersion of additive particles in the coating layer. Further, it is possible to form a coating layer surface which is less likely to be worn, peeled off, scratched or the like on the surface of the coating layer and has durability and wear resistance against repeated use. Further, it is possible to form a developer carrying member that does not cause image defects such as density unevenness and streaks due to non-uniformity in developer transport and non-uniformity in imparting charge to the developer. Further, the coating layer surface has a desired surface shape and a uniform dispersion of added particles in the coating layer, the developer layer thickness regulating blade is less likely to be scratched, and a developer such as streaks on the image does not appear. A carrier can be formed.

Further, it is possible to provide a developer carrier which is resistant to abrasion, peeling, scratches and the like on the surface of the coating layer, has durability against repeated use, and has abrasion resistance, and which can stably obtain a good image for a long period of time. Can be formed. Further, it is possible to form a magnetic particle conveying member and a charging device in which the resistance value of the surface of the coating layer is uniform, charge can be sufficiently applied to the charged body, and image defects such as density unevenness and density decrease do not occur. . In addition, the surface of the coating layer has a desired surface shape and a uniform dispersion of the added particles in the coating layer, and the transport of the magnetic particles is stable and uniform, so that the charge can be uniformly applied to the charged body. A particle transport member and a charging device can be formed.

A further object of the present invention is the abrasion of the coating layer surface,
It is resistant to peeling and scratches, has durability against repeated use, wear resistance, is stable and uniform in the transport of magnetic particles for a long period of time, and is a magnet that can evenly apply charges to charged bodies. A particle transport member and a charging device can be formed.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a developing device that is an embodiment of the present invention.

FIG. 2 is a schematic configuration view showing another embodiment of the developing device of the invention.

FIG. 3 is a schematic configuration diagram showing still another embodiment of the developing device of the present invention.

FIG. 4 is a schematic configuration diagram showing still another embodiment of the developing device of the present invention.

FIG. 5 is a schematic diagram of a magnetic brush charging member that is an embodiment of the present invention.

FIG. 6 is a schematic view of a magnetic brush charging member according to another embodiment of the present invention.

FIG. 7 is a schematic view showing a rubber roller having a coating layer of the present invention.

FIG. 8 is a schematic diagram of an example of an image forming apparatus.

FIG. 9 is a schematic diagram of a layer structure of a photoconductor.

FIG. 10 is a layer structure model diagram / equivalent circuit diagram of the photoconductor.

FIG. 11 is a schematic diagram of a configuration example of an electrophotographic digital copying machine.

[Explanation of symbols]

1 to 6 1: Photosensitive drum (electrostatic latent image holder) 2: Magnetic regulation blade 3: Hopper (toner container) 4: Developer (toner) 5: Magnet roller 6: Metal cylindrical tube 7: Conductive coating layer 8: Development sleeve (developer carrier) 9: Development bias power supply 10: Toner stirring blade 11: Interval 15: Stir chamber 16: Career 17: Development room 18: Toner chamber 21: Conductive sleeve 22: Magnet roll 23: Career 24: central core 25: Conductive layer Code of FIG. 8 1: Electrophotographic photoreceptor 2: Magnetic particle conveying member 3: Reversal developing device 3a: Non-magnetic developing sleeve 3b: Magnet 4: Transfer roller 5: Fixing device 6: Cleaning device 7: Laser beam scanner 8: Process cartridge insertion / removal guide / holding unit 9: Cartridge housing 10: Process cartridge 21: Conductive sleeve 22: Magnet roll 23: Career 9 to 11 1: photoconductor 2: Magnetic particle conveying member 11: Drum base 12: Undercoat layer 13: Positive charge injection prevention layer 14: Charge generation layer 15: Charge transport layer 16: Charge injection layer 16a: conductive particles 21: Conductive sleeve 22: Magnet roll 23: Career 101: fixing device 102: Charger 103: Magnetic particles for charging 104: Magnet roller inner conductive sleeve 105: photoconductor 106: exposure light 107: developing sleeve 108: developing device 109, 110: stirring screw 111: Developer 112: Paper transport guide 113: Transfer paper 114: Transfer roller 115: Paper transport belt 116: Process cartridge 117: Development cartridge

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 15/08 501 G03G 15/08 501C 4D075 501D 15/16 103 15/16 103 15/20 103 15/20 103 21/00 350 21/00 350 (72) Inventor Yasuhide Goseki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Ikki Saiki 3-30-2 Shimomaruko, Ota-ku, Tokyo No. Canon Inc. (72) Kenji Fujishima, 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Satoshi Otake, 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. In-house F-term (reference) 2H033 BB14 BB15 BB26 BB29 BB31 2H035 CB03 2H071 BA43 DA06 DA08 DA09 DA12 2H077 AA37 AC16 AD02 AD06 AD36 AE06 EA03 EA14 EA1 5 EA16 FA03 FA13 FA25 2H200 GA16 GA23 GA34 GA45 GA53 GA57 GB12 GB25 HA03 HB12 HB22 HB45 HB48 JA02 JA25 JB10 LC03 MA03 MA04 MA06 MA20 NA02 4D075 AB02 AB39 CA02 CA03 CA09 CA22 CA24 CA48 DA15 DB04 DB07 DB35 DB14 DB10 DB54 DC18 EB35 EB38 EB39 EB42 EC01 EC53 EC54 EC60

Claims (16)

[Claims] 1. A member for use in electrophotography having a coating layer formed by using a coating composition obtained by stirring and dispersing a coating composition comprising at least solid particles and a dispersion solvent on a cylindrical or cylindrical substrate. In the manufacturing method, as a stirring device used for the stirring dispersion, a container having a circular cross section capable of accommodating the coating composition to be stirred, a rotating shaft provided at the center of the container, and the container attached to the rotating shaft Inner surface of the container by using a stirring device having a stirring tool that rotates at a high speed having a radius reaching the vicinity of the inner peripheral surface of the container, and driving the stirring tool at a peripheral speed of 20 m / sec or more at high speed to centrifuge the coating composition. A method for producing an electrophotographic member, comprising forming a coating layer on the surface of the member by using a coating material that is pressed and dispersed in a hollow thin film while rotating and stirring. 2. The coating composition contains at least a binder resin dissolved and / or dispersed in a dispersion solvent.
A method for manufacturing the electrophotographic member according to 1. 3. The method for producing an electrophotographic member according to claim 1, wherein the solid particles are conductive particles. 4. The method for producing an electrophotographic member according to claim 1, wherein the solid particles are lubricious particles. 5. The method for producing an electrophotographic member according to claim 1, wherein the solid particles are charge controllable particles. 6. The method for producing an electrophotographic member according to claim 1, wherein the solid particles are an inorganic material having a Mohs hardness of 4 or more. 7. The solid particle is a resin particle that imparts irregularities to the surface of a coating layer, according to any one of claims 1, 2, 4 and 5.
Item 6. A method for producing a member for electrophotography according to Item. 8. The method for producing an electrophotographic member according to claim 1, wherein the solid particles are carbon particles that give unevenness to the surface of the coating layer. 9. The solid particles have an average particle size of 1 to 25 μm.
9. The method for producing an electrophotographic member according to claim 1, wherein the particles are particles that impart irregularities to the surface of the coating layer. 10. The ten-point average roughness Rz of the surface of the coating layer formed by the coating composition is 1.5 times or less the average particle size of the solid particles. Item 6. A method for producing a member for electrophotography according to Item. 11. The Rz / Ra, which is the ratio of the ten-point average roughness Rz and the arithmetic average roughness Ra of the surface of the coating layer formed by the coating composition, is 9 or less. The method for manufacturing the electrophotographic member according to any one of items. 12. The method for producing an electrophotographic member according to claim 1, wherein the coating composition contains two or more kinds of the solid particles. 13. The method for manufacturing an electrophotographic member according to claim 1, wherein the coating layer is a conductive resin layer. 14. The developer carrying member carrying and carrying the developer, wherein the formed member is a developer carrying member.
Item 6. A method for producing a member for electrophotography according to Item. 15. An external power supply while the member to be formed carries magnetic particles to form a magnetic brush, and the magnetic brush is in contact with a latent image holding member for forming an electrostatic latent image on the surface. 14. The method for producing an electrophotographic member according to claim 1, which is a magnetic particle conveying member used in a charging device that applies a voltage to charge the latent image holding member. 16. A cylindrical or columnar member having a coating layer for use in electrophotography, the member being manufactured by the manufacturing method according to any one of claims 1 to 15. The member for electrophotography, characterized in that