JP2005140975A - Developer carrier and development apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developer carrier having proper properties of imparting triboelectrification to toner, having an appropriate toner transport quantity, and also attaining stable toner electrification, even in repeated uses, and to provide a development apparatus which uses the developer carrier. <P>SOLUTION: The developer carrier is provided with at least a substrate and a conductive resin coating layer formed on the substrate surface, and the conductive resin coating layer contains at least (a) binding resin, (b) at least a particle whose surface is constituted of a carbonaceous material and whose number average particle size is 3 to 30μm, and (c) a conductive inorganic particle whose Mohs hardness is ≥ 6, and whose number average particle size is ≥2μm. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a developer carrying member used in an electrophotographic developing device and a developing device having the developer carrying member, and an improved conductive resin coating provided on a substrate of the developer carrying member. The present invention relates to a developer carrier having a layer and a developing device having the developer carrier.

  Conventionally, many methods are known as electrophotographic methods. In general, a photoconductive substance is used to form an electric latent image on an electrostatic latent image carrier (photoconductor) by various means, and then the electrostatic latent image is developed with a developer (toner). After forming the toner image and transferring the toner image onto a transfer material such as paper as necessary, the toner image is fixed on the transfer material by heat, pressure, heat-pressurization, etc. To get. The dry development system in electrophotography is mainly divided into a one-component development system that does not require a carrier and a two-component development system that uses a carrier.

  For the one-component development method, the powder cloud method using toner particles in a sprayed state, the toner on the developer carrying member having flexibility or elasticity is brought into direct contact with the electrostatic latent image surface and developed. There is a contact development method, and a jumping development method in which the toner is caused to fly toward the latent image surface by the action of the electric field between the electrostatic latent image and the developer carrier without directly contacting the toner with the electrostatic latent image surface. In particular, a contact development method or a jumping development method is often used.

  The one-component development method requires no carrier, can reduce developer replacement due to developer deterioration, and does not require a carrier and toner density adjustment mechanism in the development device, thus reducing the weight of the development device There is an advantage that it can be miniaturized.

  As toner applied to these developing methods, toner particles in which a colorant is dispersed in a binder resin are used. For example, toner particles having an average particle size of about 4 to 15 μm in which colored particles such as pigments, dyes, carbon black, or magnetic iron oxide fine particles are dispersed in a binder resin such as styrene-acrylic resin or polyester resin are used as toner. .

  The toner needs to have a predetermined positive or negative charge depending on the polarity of the electrostatic latent image being developed and the development process. As a method for imparting electric charge to the toner, there are a method for adjusting the triboelectric charge characteristics by improving the binder resin of the toner, and a method for imparting triboelectric chargeability to various particles added to the toner particles. It is common to add a specific substance called toner particles. Furthermore, there is a method using the triboelectric charging characteristics of the external additive. These combinations determine the triboelectric charging characteristics of the toner.

  These toners usually generate a triboelectric charge by contact with various members used in the developing device. In general, in the development process, when an appropriate charge is to be given to a toner, first, an appropriate material is selected as a binder resin, an additive, and a charge control agent that can sufficiently charge the toner. It is important whether this affects the developability. However, since the binder resin occupying most of the components constituting the toner can play an important role not only in the development but also in the fixing process, it is not possible to select a material that emphasizes only the triboelectric charging characteristics. In recent years, a technique for fixing at a lower temperature or lower power consumption is required from the viewpoint of energy saving. In toners, binder resins that emphasize fixing properties often have low chargeability. For example, in order to fix the toner with low energy, there is a method of increasing the low molecular weight component in the glass transition point (Tg) of the binder resin or the molecular weight distribution of the binder resin. Often has low chargeability. In addition, waxes are often added to the toner for the purpose of improving offset resistance in the fixing process and for enhancing the plasticity of the binder resin to improve fixability. These waxes tend to lower the developability of the toner. In addition, when a large amount of charge control agent is added to the toner particles in order to improve the triboelectric chargeability of the toner, most of the charge control agents are dyes or pigments, so that the charge control agent is released from the toner particles in the toner manufacturing process. Or the charge control agent present on the surface of the toner particles tends to contaminate members such as the photosensitive drum, the charging member, the developing sleeve, and the regulating blade.

  As a second means for imparting triboelectric charge to the toner, a method of adjusting the triboelectric charge of the toner by selecting and using an appropriate material for the triboelectric charge imparting member for triboelectrically charging the toner has been proposed.

  In the one-component developing method, in the developing device, the toner passes between the developer carrier and the layer thickness regulating member, and the toner contacts the developer carrier and the layer thickness regulating member when the layer is thinned. For this reason, these members affect the frictional charging of the toner. Particularly in the case of the one-component magnetic development method, the insulating magnetic toner moves on the developer carrier due to the magnetic force of the magnet built in the developer carrier, and at this time, there is an opportunity to contact the developer carrier. Therefore, the weight applied to the developer carrying member is large as frictional charging.

  As the developer carrier used in the one-component development method, for example, in a contact phenomenon method in which development is performed by directly contacting the developer carrier with the electrostatic latent image carrier, a main spindle of a metal such as stainless steel is generally used. In addition, a material obtained by molding an elastic body such as urethane rubber, EPDM rubber, or silicone rubber into a cylindrical shape, or a material in which an elastomer layer is formed on the surface of a cylindrical member made of aluminum or stainless steel is used. The rubber or elastomer contains a plasticizer, a vulcanizing agent, a release agent, a low molecular weight component, and the like, and when these come into contact with the electrostatic latent image carrier or the developer layer forming member, these members and The image may be adversely affected. Therefore, a means for preventing a bad influence by providing a barrier layer or a protective layer on the surface of the rubber layer or the elastomer layer is taken. Furthermore, it has been proposed to form the outermost layer with a material having good releasability and a resin that easily gives a frictional charge to the toner.

  On the other hand, a developer carrier used for non-contact type development is formed by forming a metal, an alloy thereof or a compound thereof as a substrate in a columnar or cylindrical shape, and the surface thereof is subjected to a predetermined surface by electrolysis, plating, blasting, or filing. What was processed so that it might become coarse is used. When a one-component magnetic developer is used, a magnet having a predetermined magnetic force and magnetic pole configuration is arranged in the cylinder of the substrate.

  However, when a developer carrying body having the above surface (hereinafter also referred to as “developing sleeve”) is used, development in the developer layer (toner layer) formed on the surface of the developer carrying body by the regulating member. The toner present in the vicinity of the surface of the developer carrier has a very high triboelectric charge, and is attracted to the surface of the developer carrier strongly, which causes the toner and the surface of the developer carrier to come later. Since there is no opportunity for friction, a suitable charge cannot be given to the developer. In such a situation, it is difficult to perform sufficient development and transfer, and the image density is lowered, and an image with unevenness of the image and having many scattered characters is likely to be generated. In order to prevent the generation of toner having such an excessive frictional charge and the adhesion of the toner to the surface of a strong developer carrying member, a conductive material such as carbon black or graphite or a solid in a frictionally chargeable resin There has been proposed a method of forming a film in which a lubricant is dispersed on a substrate of a developer carrying member (for example, Patent Document 1).

  In addition to the function of imparting an appropriate charge to the toner, the developing sleeve plays a role of stably and uniformly transporting the toner layered on the developing sleeve to the developing region. The toner transport amount on the developing sleeve is affected by the restriction of the toner layer forming part, the Coulomb force due to charging between the toner and the developing sleeve, and the magnetic force composition of the magnet, but the influence of the surface shape of the developing sleeve is considerable. large. Therefore, if the shape of the developing sleeve surface changes due to repeated use, the toner transport amount changes. With resin-coated developing sleeves containing carbon black or graphite, a low-capacity process cartridge that does not require much durability can provide sufficient performance. Change occurs, and a change in the toner conveyance amount becomes a problem (see Patent Document 1). Since the change in the toner conveyance amount also changes the contact opportunity between the toner and the developing sleeve at the same time, the frictional charge amount of the toner also changes.

  A proposal has been made to add spherical fine particles as a material for forming irregularities on the surface of the developing sleeve (for example, Patent Document 2). The method of adding spherical fine particles is a good means for forming a uniform surface shape. However, in long-term use and development methods that require strong stress on the surface of the developing sleeve, when the proposed resin fine particles are used, the surface roughness of the resin layer is reduced due to abrasion of the resin fine particles due to durability, and the toner on the resin fine particles The problem of adhesion is likely to occur.

  In the technique of adding spherical particles, a technique of forming a resin layer to which conductive spherical particles having a true density of 3 or less are added has been proposed as a means for improving durability (for example, Patent Document 3). Further, it has been proposed to use a high-hardness silica-based material as an unevenness imparting substance (for example, Patent Document 4). Since the toner conveyance amount is stably maintained at a constant amount, and the wear resistance of the developing sleeve is also good, the stress on the coating layer by the toner between the layer thickness regulating member and the developing sleeve is alleviated to some extent. The durability of the resin coating layer is improved (see Patent Documents 3 and 4). However, in the resin portion existing between the particles, due to contact with the toner, the film thickness of the resin coating layer is reduced due to wear in repeated use over a long period of time. A technique for reinforcing the resin coating layer by sharing spherical particles and fibrous materials such as potassium titanate whiskers is proposed (for example, Patent Document 5). However, although the method of adding these fibrous substances is effective in increasing the strength of the resin coating layer, the shape of the fibrous substance is indeterminate and it is difficult to control the size of the fibrous substance. It is difficult to form with a constant. In addition, when the resin portion is scraped by repeated use, the change in surface roughness tends to be remarkable. In a two-component developing apparatus, it is proposed to add a granular material having a Mohs hardness of 6 or more to form a surface roughness and to reinforce the resin coating layer (for example, Patent Document 6). A technique has been proposed in which silica having two types of particle diameters is added as an inorganic substance, surface roughness is formed with large silica particles, and toner is triboelectrically charged with small silica particles (for example, Patent Document 7). However, since silica-based materials are not very compatible with the resin, dispersion in the resin layer is poor and it is difficult to form a uniformly dispersed resin coating layer. Further, when a large amount of fine particles such as 5 to 100 nm are added to the resin layer, the resin layer becomes brittle and it is difficult to obtain high durability. Moreover, when many materials with poor conductivity such as silica are used, the volume resistance of the coating layer is increased, so that there is a high possibility of being charged up.

  As a layer thickness regulating member (hereinafter also referred to as “regulating blade”) used in the developing device, for example, a type that has a narrow gap between the regulating blade and the developing sleeve and regulates the toner conveyance amount, the regulating blade is the developing sleeve. In some cases, the regulation is performed by elastic contact in some cases. Generally, materials such as metal and rubber are used. When elastically contacting the developing sleeve, a rubber such as urethane rubber or silicone rubber, or a phosphor bronze or stainless steel plate material is used. These triboelectric charging materials are directly processed into a blade shape, attached as a chip to a plate material, plated, or coated with a triboelectric charging resin or elastomer. As described above, the regulating blade used in contact with (pressing) the developer carrying member is generally used with a surface having a relatively low hardness, as described above. Therefore, when the hard-forming, low-lubricity, or irregular-shaped particles are used as the roughness-forming particles contained in the developer-carrying resin coating layer, the regulating blade is damaged in a streak shape and the resulting toner image This is likely to cause streak images.

  A developing sleeve is disclosed in which a coating is formed by electrodeposition coating, and semiconductive inorganic fine particles are localized and dispersed in the resin layer. Further, carbon black or nonconductive powder is added. (For example, Patent Document 8). Furthermore, it has been proposed to form surface irregularities using a relatively large conductive inorganic powder in a resin layer similarly formed by electrodeposition coating (for example, Patent Document 9). However, the presence of the additive material in a localized manner is generally not preferable for developability in terms of the uniformity of charging, and when hard particles protrude as described above, the regulation blade is adversely affected. Therefore, even with these configurations, it is difficult to say that the image is stable over a long period of time.

Furthermore, an improved technique in a system to which surface roughness forming particles are added has been proposed (for example, Patent Documents 10, 11, and 12).
JP-A-01-277265 Japanese Patent Laid-Open No. 03-200986 Japanese Patent Laid-Open No. 08-240981 Japanese Patent Laid-Open No. 04-078881 Japanese Patent Laid-Open No. 10-186839 JP 2002-189339 A Japanese Patent Application Laid-Open No. 07-306586 Japanese Patent Laid-Open No. 08-160737 Japanese Patent Laid-Open No. 08-160738 Japanese Patent Laid-Open No. 08-179616 Japanese Patent Application Laid-Open No. 08-179617 JP-A-10-293454

  In the developer carrying member, it is required that the toner has good triboelectric chargeability and that it has an appropriate surface roughness in order to secure an appropriate amount of toner transport. It is required that the charging of the is stable. That is, as a material for the resin coating layer of the developer carrying member, the material configuration is such that the triboelectric charge is moderately imparted to the toner with good triboelectric chargeability and does not cause charge-up, and the material is uniformly dispersed. Therefore, it is preferable to select a material configuration that has a uniform surface shape, wear resistance, and a small change in the amount of toner transported due to long-term durability for development stability.

  For example, in a high-speed machine using a one-component magnetic developer, the developing sleeve is stable and has a triboelectric charging property to the magnetic toner, and the surface of the developing sleeve is less worn and the change in surface roughness is small. In addition, the occurrence of contamination on the sleeve surface is suppressed, the occurrence of ghost, unevenness, blotch, and fog is suppressed, the predetermined image density is maintained, and the output of a large number of high-quality images is replaced with a developer carrier. It is required to achieve without.

  Also, in a system using a one-component magnetic or one-component non-magnetic developer, in a developing device in which the developer regulating blade and the developer stripping supply member are in strong pressure contact with the developing sleeve, the developing sleeve due to strong stress Prevents surface abrasion and prevents toner contamination and toner fusion to maintain the shape of the surface of the developing sleeve and suppress changes in the surface of the developing sleeve due to dropout of additives, ghost, unevenness, blotch, fog, There is a need for a developing sleeve and a developing device that can provide a high-definition toner image in which the occurrence of a decrease in image density or the like is suppressed.

  An object of the present invention is to provide a developer carrying member that can achieve the above requirements and a developing device using the same.

The present invention develops an electrostatic latent image formed on an electrostatic latent image carrier with a one-component developer carried and conveyed by the developer carrier to form a toner image. In the carrier,
The developer carrier has at least a substrate and a conductive resin coating layer formed on the substrate surface,
The conductive resin coating layer has at least (a) a binder resin resin, and (b) at least a surface for forming irregularities on the conductive resin coating layer. And (c) conductive inorganic particles having a Mohs hardness of 6 or more, a number average particle size of 2 μm or more, and an average particle size smaller than the number average particle size of the unevenness-forming particles. And a developer carrying member.

Further, the present invention has a container for containing at least a developer and a developer carrier for carrying and transporting the developer stored in the container, and a developer layer is formed on the developer carrier by a developer regulating member. The developer on the developer carrying member is conveyed to a developing area facing the electrostatic latent image carrier, and the electrostatic latent image on the electrostatic latent image carrier is developed with the developer to form a toner image. In the developing device for forming
The developer carrier has at least a substrate and a conductive resin coating layer formed on the substrate surface,
The conductive resin coating layer has at least (a) a binder resin resin, and (b) at least a surface for forming irregularities on the conductive resin coating layer. And (c) conductive inorganic particles having a Mohs hardness of 6 or more, a number average particle size of 2 μm or more, and an average particle size smaller than the number average particle size of the unevenness-forming particles. To a developing device.

  In the present invention, it is preferable that the conductive resin coating layer further contains a charge control agent.

  In the present invention, the resin coating layer further includes insulating inorganic particles having a Mohs hardness of 6 or more having a number average particle size of 2 μm or more and an average particle size smaller than the number average particle size of the unevenness forming particles. It is also possible to contain both the charge control agent and the insulating inorganic particles.

  As a more preferable aspect of the present invention, the following configuration can be given.

That is, the conductive inorganic particles have a conductivity of 10 ⁻⁶ Ω · cm or less.

  The average circularity SF-1, which is the average value of the circularity obtained by the following formula (1) for the conductive inorganic particles and / or the insulating inorganic particles, is 0.60 or more.

Circularity = (4 × A) / {(ML) ² × π}
[In the formula, ML represents the maximum length of the Pythagorean method of the particle projection image, and A represents the area of the particle projection image. ]
Conductive inorganic particles and / or insulating inorganic particles are organically treated.

  The conductive resin coating layer is provided with conductivity by dispersing conductive fine powders such as carbon black and graphite.

  The conductive resin coating layer further contains a lubricating substance.

  Since the developer carrying member of the present invention has good triboelectric chargeability to the developer of the developer carrying member and excellent wear resistance, uniform developer transportability, uniform and appropriate tribocharging to the developer. Therefore, it is possible to maintain a high-definition image free from image density reduction, fogging, streaks, unevenness, and blotch over a long period of time.

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

  As described above, a developer carrier having a conductive resin coating layer in which crystalline graphite is dispersed in a binder resin provided on a sleeve has been put to practical use and used in products such as copying machines and laser printers. Yes. The resin coating layer has irregularities on the surface by the action of crystalline graphite. However, since crystalline graphite itself has a cleavage property, it is brittle and wears due to the force received from the developer and the layer thickness regulating blade, and at the same time the surface roughness is reduced. Accordingly, the conductivity of the resin layer is maintained, but the developer transport amount is reduced due to the reduction in surface roughness, so that the toner is likely to be charged up. In the obtained image, sleeve ghost, fog, density Decrease is likely to occur. Therefore, in order to cope with an increase in the volume of process cartridges used in copiers and laser printers, it has been required to improve the above-described technology and maintain the developer transport amount. On the other hand, irregularities are formed by adding spherical particles in addition to crystalline graphite, and the developer transportability can be maintained. In particular, the conductive spherical particles are, for example, non-conductive spherical particles formed of a resin, and when the spherical particles are exposed on the surface due to wear of the resin coating layer, the non-insulating particles are the friction of the developer. It is easy to affect the chargeability, and it tends to affect the triboelectric charge (tribo) of the developer due to durability, whereas the conductive spherical particles are superior because it hardly affects the triboelectric charge (tribo). It can be said that.

  However, even in a system in which surface irregularities are formed with these spherical particles, it cannot always be satisfied when a longer life is required, and wear tends to progress due to durability. That is, as schematically shown in FIG. 1, a resin layer exists between particles that form surface irregularities, and wear proceeds in the resin layer portion. In such a situation, spherical particles are present, and the resin coating layer between the spherical particles is worn, resulting in an increase in surface roughness and a tendency to increase the developer conveyance amount, and the frictional charge amount of the toner is reduced. This tends to cause reversal fog, low density, and developing sleeve negative ghost. In addition, since the amount of scraping of the resin coating layer is partially different, an image having a lot of unevenness such as a streak image or a spot image tends to be formed. Further, when the wear progresses, the underlying developing sleeve base is exposed, so that the partial toner becomes overcharged and blotches are likely to occur. Therefore, it is required that the resin coating layer between the particles (rough particles) forming the surface irregularities is also reinforced.

  A coating layer has been proposed in which fine silica of 5 to 100 nm is dispersed between coarse particles of silica having a coarse particle diameter, but according to the results of investigations by the present inventors, silica fine particles are coated with resin. It was found that the reinforcing effect of the layer could not be obtained. The reason is not necessarily clear, but it is presumed that the toner particles are much larger than such fine particles, and the fine particles are worn simultaneously with the resin layer by the force of the toner. Experimentally, it has been found that the larger the particle size of the developer particles carried on the developer carrier, the larger the particle size of the reinforcing particles needs to be. Usually, toner having a weight average particle diameter of about 4 to about 15 μm is used. From experimental results, it has been found that it is preferable to use particles having a particle diameter of 2 μm or more as reinforcing particles for the resin coating layer.

  On the other hand, when the hardened particles 4 having reinforcing properties are used as the roughened particles, the layer thickness regulating blade may be damaged as described above, which is not preferable. As the rough particles 3, it is preferable to use rough particles having at least a surface formed of carbon. Since the carbonaceous particles on the surface have high lubricity and conductivity, the layer thickness regulating blade is hardly damaged and the toner 9 is hardly fused. Further, even when exposed on the surface, the conductivity is not impaired and the frictional charge of the toner is not lowered.

  FIG. 2 shows a schematic diagram of an example of a preferred embodiment of the present invention. In FIG. 2, reference numeral 1 denotes a developer carrier substrate, and 2 denotes a conductive resin coating layer. Further, rough carbon particles 3 having a carbon surface and reinforcing high hardness particles 4 having an average particle size smaller than that of the rough particles 3 are dispersed in the resin coating layer. More preferably, conductive fine particles 6 as a conductive agent not displayed here and / or fine particles 6 having lubricity (which may be conductive or may be used as a conductive agent) are dispersed. As the high hardness particles 4 for reinforcement, hard particles are used, but as a measure of hardness, a Mohs hardness of 6 or more is preferable. Further, the reinforcing high-hardness particles 4 are contained in the resin layer 2 as described above, thereby affecting the triboelectric charging property of the developer. When non-conductive particles are used, the conductive inorganic particles are selected as the high hardness particles 4 because there is an influence on the triboelectric chargeability of the toner 9. It has been proposed to use particles having a Mohs hardness of 6 or more as a resin coating layer of a developer carrying member for a two-component developing device, but unlike a two-component developer having a carrier that frictionally charges toner, a one-component system is used. In the developer, the material selection of the resin coating layer of the developer carrier is required in order to appropriately and stabilize the frictional charge of the toner.

  Furthermore, the following points are mentioned as a more preferable aspect of the present invention. That is, such conductive reinforcing particles do not extremely affect the triboelectric charge of the toner, but generally do not easily induce triboelectric charge of the toner. Tends to decrease with particle addition. In particular, in order to reinforce the resin layer, the tribo value of the toner decreases when it is added in large quantities. Therefore, it becomes necessary to compensate for the toner tribo that has been lowered by the reinforcement of the resin coating layer. One of such compensation forms is a method in which the charge control agent 7 is added to the resin layer in addition to the conductive inorganic particles as the high hardness particles 4 and used. The charge control resin is connected like a charge control agent. It may be used by adding to the resin. Another method is to further add the insulating inorganic particles 8 that easily impart triboelectric charge to the toner together with the conductive inorganic particles in the resin layer, and use the conductive inorganic particles and the insulating inorganic particles in combination. The insulating inorganic particles can also contribute to abrasion resistance when the Mohs hardness is 6 or more, and the toner tribo can be adjusted by adjusting the amount of addition with the conductive inorganic particles. Mohs hardness means old Mohs hardness: 1 for talc, 2 for gypsum, 3 for calcite, 4 for fluorite, 5 for apatite, 6 for feldspar, 7 for crystal, 8 for yellow jade, 9 for steel ball, diamond The value is determined by a qualitative method in which the standard mineral and the sample are pulled together and the scratch is soft and the hardness is small. Furthermore, for the reasons described above, the insulating inorganic particles are preferably roughened and the average particle size is preferably smaller than that of the particles 3, and the average particle size is more preferably 2 μm or more in terms of wear resistance. A schematic diagram of this embodiment is shown in FIGS. Moreover, it is also possible to use a charge control agent and insulating inorganic particles in combination as required.

  Next, the configuration of the developer carrying member of the present invention will be described in more detail.

  The developer carrying member of the present invention has a substrate 1 and a resin coating layer 2.

  The developer carrier base 1 includes a cylindrical member, a columnar member, a belt-like member, and the like. In a developing method that is not in contact with the photosensitive drum, a rigid cylindrical tube or a solid rod such as a metal is used. 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 subjected to polishing, grinding, or the like, is preferably used. These substrates 1 are used after being molded or processed with high precision in order to improve the uniformity of the image. For example, the straightness in the longitudinal direction is preferably 30 μm or less or 20 μm or less, more preferably 10 μm or less. Further, when the developing sleeve is rotated against the vertical surface through a uniform spacer, the fluctuation of the gap between the vertical surface and the developing sleeve is 30 μm or less or 20 μm or less, more preferably 10 μm or less. preferable. Aluminum is preferably used for the substrate 1 because of material cost and ease of processing.

  Further, as the substrate 1 having an elastic layer, in the case of a developing method in which a core member and a cylindrical member having a layer structure including rubber, elastomer such as urethane, EPDM, and silicon are in direct contact with a developer carrier. Preferably used.

  As the binder resin for the conductive coating layer 2 constituting the developer carrying member of the present invention, generally known resins can be used. For example, thermoplastic resins such as styrene resin, vinyl resin, polyethersulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, fluororesin, fiber resin, acrylic resin; epoxy resin, polyester resin, alkyd resin And heat or photo-curable resins such as phenol resin, melamine resin, benzoguanamine resin, polyurethane resin, urea resin, silicone resin, polyimide resin, and the like. Among them, those having releasability such as silicone resin, fluorine resin, or polyether sulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, phenol resin, polyester resin, polyurethane resin, styrene resin, acrylic resin Those having excellent mechanical properties are preferably used. Furthermore, silicone resin, polyamide resin, acrylic resin, epoxy resin, phenol resin, melamine resin, and benzoguanamine resin are preferable from the viewpoint of imparting triboelectric charge to the developer.

In the present invention, the coating layer formed on the developer carrier by the above-described forming material is fixed on the developer carrier due to charge-up, or the developer carrying that occurs when the developer is charged up. In order to prevent poor application of frictional charge from the surface of the body to the developer, the volume resistance value of the resin coating layer is preferably 10 ⁴ Ω · cm or less, more preferably 10 ³ Ω · cm or less. Is good. If the volume resistance value of the conductive coating layer on the surface of the developer carrying member exceeds 10 ⁴ Ω · cm, it is easy to cause poor frictional charging to the developer. As a result, blotches (spot images and wave pattern images) and images Concentration tends to decrease.

  In the present invention, in order to adjust the resistance value of the resin coating layer to the above-mentioned value, it is preferable to contain the following conductive material in the coating layer. Examples of the conductive substance used at this time include fine powders of metal powders such as aluminum, copper, nickel, silver, antimony oxide, indium oxide, tin oxide, titanium oxide, zinc oxide, molybdenum oxide, titanic acid. Examples thereof include conductive metal oxides such as potassium, various carbon fibers, furnace black, lamp black, thermal black, acetylene black, channel black and other carbon blacks, carbon materials such as graphite, and metal fibers.

  In the present invention, among these, carbon black, particularly conductive amorphous carbon, is excellent in electric conductivity, is charged into a polymer material to impart conductivity, and can be controlled by simply adding the amount thereof. Since conductivity can be obtained, it is preferably used. Amorphous carbon is preferred because the dispersion stability and coating stability can be improved due to the thixotropic effect of the paint.

  In the present invention, the amount of carbon black added varies depending on the particle size of the carbon black, but is preferably in the range of 1 to 100 parts by mass with respect to 100 parts by mass of the binder resin. If it is less than 1 part by mass, it is usually difficult to lower the resistance value of the coating layer to a desired level, and there is a high possibility that toner adheres to the binder resin used in the developer carrier coating layer. If it exceeds 100 parts by mass, the strength (wearability) of the resin coating layer 2 tends to decrease.

  Furthermore, in the present invention, a solid lubricant can be mixed in the resin coating layer 2 in order to further reduce the adhesion of the developer to the surface of the developer carrying member. Examples of the solid lubricant that can be used in this case include molybdenum disulfide, boron nitride, graphite, graphite fluoride, silver-selenium niobium, calcium chloride-graphite, and talc. Of these, molybdenum disulfide, graphite, and boron nitride are more preferably used. Moreover, it is preferable to make the addition amount of these solid lubricants which can be used by this invention into the range of 1-100 mass parts with respect to 100 mass parts of binder resin. When the amount is less than 1 part by mass, the effect of improving the adhesion of the developer to the binder resin surface of the coating layer is small, and when it exceeds 100 parts by mass, a material containing a large amount of fine powder having a particle size of the order of submicron is used. In this case, the strength (wearability) of the coating layer tends to decrease. These lubricating particles preferably have a number average particle diameter of 0.2 to 20 μm, more preferably 1 to 15 μm. When the number average particle diameter of the lubricating particles is less than 0.2 μm, it is not preferable because sufficient lubricity is not obtained. When the number average particle diameter exceeds 20 μm, the shape of the surface of the conductive coating layer is reduced. The influence is large and the surface property tends to be non-uniform, and the frictional charge of the toner tends to be non-uniform. In the present invention, it is preferable that the number average particle diameter of the lubricating particles is smaller than the number average particle diameter of the roughened particles 3 because of the characteristics of the configuration of the resin coating layer. Since the lubricating particles are not particularly spherical, the effect on the surface roughness of the resin coating layer compared to the spherical rough particles 3 is small when compared with the same particle size, but is larger than 0.2 μm and rough. It is preferably smaller than the number average particle diameter of the particles. If the number average particle size of the roughened particles is larger, the influence of the lubricating particles on the initial surface roughness becomes large. There is a high possibility of affecting the transport amount of the agent.

  As the particles that give unevenness to the conductive resin coating layer 2 in the present invention, particles having at least a carbonaceous surface are used. By making the surface carbonaceous, it has conductivity and lubricity, and is effective in preventing charge-up, preventing toner adhesion / fusion, preventing torque-up by the developing sleeve, and preventing scratches on the layer thickness regulating blade.

  The particles having a carbonaceous surface used in the present invention have a number average particle diameter of 3 to 30 μm, preferably 3 to 20 μm. As described above, the abrasion resistance effect due to the addition of inorganic particles needs to have a number average particle size of 2 μm or more, and in order to suppress the adverse effects due to the addition of inorganic particles, the average particle size of carbon particles is It is preferably larger than the average particle size of the inorganic particles. In particular, when the number average particle diameter of the carbon particles is 3 μm or more, there is an effect of imparting a uniform roughness to the surface. Therefore, it is easy to stabilize the coating amount of the developer, and the developer can be charged quickly and uniformly. This is advantageous because it is difficult for toner charge-up, toner contamination and toner fusion to occur, ghosts are unlikely to occur, and image density is unlikely to decrease. Carbon particles having a number average particle diameter of 3 μm or more give an effect of suppressing wear of the resin coating layer 2. On the other hand, when the number average particle diameter exceeds 30 μm, the surface roughness of the coating layer becomes too large, and the frictional charge of the toner is likely to be uneven and insufficient, and when the coating layer thickness is low, particles can fall off. The mechanical strength of the coating layer is likely to decrease.

  Examples of the carbonaceous particle having a surface include carbon particles obtained by the following method. Particles coated with bulk mesophase pitch by mechanochemical method on the surface of spherical resin particles such as phenol resin, naphthalene resin, furan resin, xylene resin, divinylbenzene polymer, styrene-divinylbenzene copolymer, polyacrylonitrile And conductive spherical carbon particles that are carbonized and / or graphitized by baking in an inert atmosphere or after being heat-treated in an oxidizing atmosphere. The conductive spherical carbon particles obtained by this method are preferable because crystallization of the coating portion of the obtained spherical carbon particles proceeds when graphitized, so that the conductivity and lubricity are further improved. The conductive spherical carbon particles obtained by the above-described method can control the conductivity of the obtained spherical carbon particles by changing the firing conditions, and are preferably used in the present invention.

  Further, for example, the following graphitized particles having a degree of graphitization PA (002) satisfying 0.20 ≦ PA (002) ≦ 0.95 can be preferably used. The degree of graphitization P (002) is said to be the Franklin P value. By measuring the lattice spacing d (002) obtained from the X-ray diffraction diagram of graphite, d (002) = 3.440-0. 0.06 (1-P2). This P value indicates the proportion of the disordered portion of the carbon hexagonal mesh plane stack, and the smaller the P value, the greater the degree of graphitization.

  The graphitized particles are different from the artificial graphite described in JP-A-02-105181 and JP-A-03-036570 or crystalline graphite made of natural graphite in the raw materials and manufacturing process of the graphitized particles. Therefore, although the graphitized particles have a slightly lower degree of graphitization than the crystalline graphite used in the past, they have high conductivity and lubricity like the crystalline graphite used in the past, and the shape of the particles is further reduced. Unlike the flakes or needles of crystalline graphite that have been used in the past, they are characterized by being roughly spherical and having relatively high hardness.

  The degree of graphitization PA (002) of the graphitized particles used in the present invention is preferably 0.20 ≦ PA (002) ≦ 0.95, and 0.25 ≦ PA (002) ≦ 0.75. It is more preferable. When PA (002) does not exceed 0.95, the toner charge-up due to the decrease in conductivity and lubricity is suppressed, and the occurrence of sleeve ghost, fog and image density is suppressed. . Furthermore, when an elastic blade is used, the occurrence of blade flaws can be suppressed, so that streaks and uneven density are less likely to occur in the image. On the other hand, when PA (002) is 0.20 or more, the wear resistance of the graphitized particles is better, the wear resistance of the coating layer surface, the mechanical strength of the resin coating layer, and the toner resistance. It is easy to obtain an effect on charge imparting properties.

  The method for obtaining graphitized particles is preferably the following method, but is not necessarily limited to these methods. Graphitization using particles that are optically anisotropic and have a single phase such as mesocarbon microbeads and bulk mesophase pitch as a raw material increases the graphitization degree of the graphitized particles and is spherical. It is preferable for maintaining the shape. The optical anisotropy of the above-mentioned raw materials is caused by the lamination of aromatic molecules, and the ordering is further developed by the graphitization treatment, and graphitized particles having a high degree of graphitization are obtained. In the case of using a bulk mesophase pitch, it is preferable to use one that is softened and melted under heating in order to obtain spherical and highly graphitized particles. A typical method for obtaining a bulk mesophase pitch is, for example, a mesophase pitch obtained by extracting β-resin from a coal tar pitch by solvent fractionation and subjecting it to hydrogenation and heavy treatment. Moreover, it is a mesophase pitch obtained by pulverizing after a heavy treatment, and then removing a solvent soluble part with benzene or toluene. This bulk mesophase pitch preferably has a quinoline soluble content of 95% by mass or more. In the case of 95% by mass or more, the inside of the particles is more likely to be liquid phase carbonized, and solid phase carbonization is difficult, so that the particles are less likely to remain in a crushed state, and a spherical shape is easily obtained. As a method of graphitizing using mesophase pitch, the bulk mesophase pitch is finely pulverized to 2 to 25 μm, and this is heat-treated at about 200 ° C. to 350 ° C. in air to be lightly oxidized. By this oxidation treatment, only the surface of the bulk mesophase pitch is infusible, and melting and fusion during the graphitizing heat treatment in the next step are prevented. The oxidized bulk mesophase pitch preferably has an oxygen content of 5 to 15% by mass. It is preferable that the oxygen content is 5% by mass or more because fusion between particles during heat treatment is less likely to occur. On the other hand, an oxygen content of 15% by mass or less is less oxidized to the inside of the particle, and the shape is It is difficult to graphitize in a crushed state, and a spherical product is easily obtained.

  Next, the oxidized bulk mesophase pitch is carbonized by primary firing at about 800 to 1,200 ° C. in an inert atmosphere such as nitrogen or argon, followed by about 2,000 to 3,500 ° C. Desired graphitized particles can be obtained by secondary firing. In addition, as a method of obtaining mesocarbon microbeads that are another preferable raw material for obtaining graphitized particles, for example, heat treatment of coal-based heavy oil or petroleum-based heavy oil at a temperature of 300 to 500 ° C., After the polycondensation produces crude mesocarbon microbeads, the reaction product is subjected to treatments such as filtration, stationary sedimentation, and centrifugation, and then the mesocarbon microbeads are separated, and then a solvent such as benzene, toluene, xylene, etc. And then dried. As a method of graphitizing using mesocarbon microbeads, it is possible to prevent the coalescence of particles after graphitization by first mechanically dispersing mesocarbon microbeads after drying with a gentle force that does not cause destruction. It is preferable for obtaining a uniform particle size. The mesocarbon microbeads that have finished the primary dispersion are primarily heat-treated and carbonized at a temperature of 200 to 1,500 ° C. in an inert atmosphere. It is preferable for the carbide that has undergone the primary heat treatment to mechanically disperse the carbide with a mild force that does not destroy the carbide in order to prevent coalescence of the particles after graphitization and to obtain a uniform particle size. The carbide that has undergone the secondary dispersion treatment is subjected to secondary heat treatment at about 2,000 to 3,500 ° C. in an inert atmosphere, whereby desired graphitized particles are obtained. Further, it is preferable that the graphitized particles obtained from the raw materials have a uniform particle size distribution to some extent by classification in order to make the surface shape of the resin coating layer uniform. The firing temperature of the graphitized particles is preferably from 2,000 to 3,500 ° C, more preferably from 2,300 to 3,200 ° C.

  When the calcination temperature is 2,000 ° C. or higher, the graphitized particles are likely to have a sufficient degree of graphitization, and the conductivity and lubricity are unlikely to decrease, so that toner charge-up hardly occurs and image quality is unlikely to deteriorate. Furthermore, even when an elastic blade is used, blade scratches are less likely to occur, and stripes and density unevenness are less likely to occur in the image. When the firing temperature is 3,500 ° C. or lower, the graphitized particles do not become too high in graphitization, so that sufficient hardness of the graphitized particles can be obtained, and the coating layer surface has good wear resistance. In addition, the mechanical strength of the resin coating layer and the charge imparting property to the toner can be easily obtained.

The particles that give unevenness to the conductive resin coating layer preferably have a volume resistance of 10 ⁶ Ω · cm or less. If the volume resistance value exceeds 10 ⁶ Ω · cm, the volume resistance value of the entire resin coating layer is increased. If the volume resistance of the resin coating layer itself increases, the concentration of particles and fog are likely to occur due to the particles. Become.

Examples of the conductive inorganic particles used in the present invention include boron carbide, titanium carbide, zirconium boride, titanium boride, silicon carbide, calcium boride, titanium nitride, silicon boride, and molybdenum carbide. For the reasons described above, it is preferable that the conductive inorganic particles used have a number particle size of 2 μm or more, a number average particle size is coarse, and smaller than the particles. When the number average particle diameter is smaller than 2 μm, the reinforcing effect is small and the wear tends to progress, and the image tends to be affected. If the particle size is larger than the number average particle size of the roughened particles, the surface roughness and the change in surface roughness are greatly affected, and the layer thickness regulating blade is damaged, and this also tends to affect the image. In particular, boron carbide and the like are preferably used in view of dispersion stability when formed into a paint because the true density is as small as ³ g / cm ³ or less.

Here, the conductive inorganic particles are those having a volume resistance of 10 ⁶ Ω · cm or less. When the volume resistance value exceeds 10 ⁶ Ω · cm, the volume resistance value of the entire resin coating layer is increased. When the volume resistance of the resin coating layer itself increases, toner due to the particles is likely to be generated. It tends to be thin and fog.

  Examples of the insulating inorganic particles used in the present invention include aluminum borate, aluminum oxide, silicon nitride, aluminum nitride, boron nitride, silicon oxide, and cerium oxide. In particular, in order to increase the triboelectric charge amount of the negatively chargeable toner, particles that are more easily positively charged than the toner itself are preferable, and aluminum oxide particles and aluminum borate particles can be preferably used.

  As the insulating inorganic particles, like the conductive inorganic particles, it is preferable to use particles having a number particle diameter of 2 μm or more and a coarse number average particle diameter smaller than the particles. When the number average particle diameter is smaller than 2 μm, the reinforcing effect is small and the wear tends to progress, and the image tends to be affected. When the number is larger than the number average particle diameter of the roughened particles, the surface roughness and the surface roughness change are greatly affected, and further, the layer thickness regulating blade is damaged, and this also tends to affect the image.

  These conductive inorganic particles and / or insulating inorganic particles preferably have an average circularity SF-1, which is an average value of circularity obtained by the following formula (1), of 0.60 or more.

Circularity = (4 × A) / {(ML) ² × π}
[In the formula, ML represents the maximum length of the Pythagorean method of the particle projection image, and A represents the area of the particle projection image. ]
When the circularity SF-1 is 0.60 or more, the uneven shape is uniform in the fine unevenness of the resin layer in the gap portion where the rough particles are not present, and the triboelectric charge amount of the toner is also uniformed and stabilized.

  For example, as a result of the study by the present inventors, there is a method in which whiskers are used as a reinforcing agent. In this case, if the same material having high hardness is used, the strength of the resin coating layer formed on the substrate (whichever is used) It was found that the (scratch resistance) was improved, but when viewed with respect to the surface unevenness, the granular material was able to form more uniform unevenness than the whisker, and the amount of developer transported by the developer carrier was also uniform. Along with this, it was found that the triboelectric charge amount of the developer was also stabilized. That is, even if whiskers are used, unevenness on the surface is formed and can be diverted in a process in which there is only unevenness. For example, a developing method using a thin layer of developer on the developer carrier is used. In a more accurate process for supplying a higher-definition image, a particulate material is preferred in that uniformity can be maintained over the coating layer surface of the developer carrier and the entire coating layer. Further, even in this granular material, the closer to a spherical shape, the more stable the transport amount and triboelectric charge amount of the developer layer.

  It is further preferred that the conductive inorganic particles and / or the insulating inorganic particles are organically treated. Examples of such an organic treatment method include a silane coupling agent that reacts or physically adsorbs with the inorganic particles, a treatment method with an organic metal compound such as a titanium coupling agent, a treatment method with an organic silicon compound such as silicone oil, or Examples include a method of treating with an organic silicon compound such as silicone oil after treating with a coupling agent or simultaneously with a coupling agent.

Examples of the coupling agent suitably used as the inorganic particle treating agent in the present invention include a silane coupling agent and a titanate coupling agent.
Examples of the silane coupling agent include known ones (for example, those conventionally used for surface modification of silica and glass). The following general formula (1) RmSiYm
R: alkoxy group m: integer of 1 to 3 Y: alkyl group n: silane compounds represented by integers of 1 to 3 are listed. For example, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, γ-chloropropylmethyldimethoxy Silane, γ-mercaptopropylmethyldimethoxysilane, stearyltrimethoxysilane, and diphenyldiethoxysilane can be used.

  In the present invention, the silane coupling agent as described above is preferably 0.0001 to 0.5 parts by mass (more preferably 0.001 to 0.2 parts by mass) with respect to 100 parts by mass of (untreated) inorganic particles. Part) used.

  When the amount of the coupling agent used is less than 0.0001 parts by mass, the effect of using the coupling agent is not recognized. On the other hand, when the amount used exceeds 0.5 parts by mass, it is involved in the reaction with the inorganic particles. This is not preferable because a coupling agent that does not become easily generated.

  Next, the general formula of a titanium coupling agent is shown below.

  Specific examples of the titanium coupling agent represented by the above general formula include the following compounds.

  The treatment amount of the titanium coupling agent with respect to the inorganic particles varies depending on the particle size and surface structure of the inorganic particles, but is preferably 0.0001 to 0.5 parts by mass with respect to 100 parts by mass of the inorganic particles. When the treatment amount of the aluminum coupling agent is less than 0.0001 parts by mass, the effect on the dispersibility of the inorganic particles is small, and when it exceeds 0.5 parts by mass, there are many free coupling agents that do not bind to the inorganic particles. This is not preferable.

  Examples of the aluminum coupling agent include acetoalkoxyaluminum diisopropylate. It is preferable to use 0.0001 to 0.5 parts by mass of the treatment amount for the inorganic compound particles with respect to 100 parts by mass of the inorganic compound. When the treatment amount of the aluminum coupling agent is less than 0.0001 parts by mass, there is little effect on the dispersibility of the inorganic compound particles, and when it exceeds 0.5 parts by mass, a free coupling agent that does not bind to the inorganic compound is present. A large number of occurrences are undesirable.

  Each of the above coupling agents may be used as a combination of two or more as required.

  Examples of a method for treating inorganic particles with a coupling agent include an organic solvent method and an aqueous solution method. In general, the treatment by the organic solvent method is a method in which a coupling agent is dissolved in an organic solvent (alcohol, benzene, halogenated hydrocarbon, etc.) containing a hydrolysis catalyst together with a small amount of water, and inorganic compound particles are immersed therein. The solid-liquid separation is performed by filtration or pressing, and dried at about 120 to about 130 ° C. In addition, the aqueous solution method is a method in which 0.5% by mass of a coupling agent is hydrolyzed in water having a constant pH or a mixed solvent of water and an organic solvent, and after immersing inorganic particles therein, a solid liquid is similarly formed. It is separated and dried.

  As another organic treatment, silicone oil is generally represented by the following formula.

R: C ₁ -C ₃ alkyl group R ′: Silicone oil-modified group R ″: alkyl, halogen-modified alkyl, phenyl, modified phenyl, etc. R ″: C ₁ -C ₃ alkyl group or alkoxy group Preferred silicone oil is 25 A viscosity of 0.5 to 1,000 mm ² / s, preferably 1 to 1,000 mm ² / s, is used at 0 ° C. Silicone oil having a molecular weight that is too low may generate a rare component by heat treatment. In addition, if the molecular weight is too high, the viscosity becomes too high to make the operation difficult.For example, the types of silicone oil include methyl hydrogen silicone oil, dimethyl silicone oil, phenylmethyl silicone oil, chlorophenyl methyl silicone oil. , Alkyl modified silicone oil, fatty acid modified silicone Oil, polyoxyalkylene-modified silicone oil, fluorine-modified silicone oil is preferable.

  The treatment with the silicone oil can be performed, for example, as follows. If necessary, the inorganic particles are vigorously disturbed while heating, and sprayed or vaporized with the silicone oil or a solution thereof, or the inorganic particles are made into a slurry and stirred. It can be treated by dripping silicone oil or a solution thereof. These silicone oils are used singly or as a mixture of two or more or in combination or multiple treatments. Moreover, you may use together with the process by a coupling agent.

Charge control agents include negative charge control agents and positive charge control agents. For example, there are the following substances to control the negative charge. For example, organometallic 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. Moreover, there are the following substances for positively charging. Modified products with nigrosine and fatty acid metal salts, etc., quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and oniums such as phosphonium salts which are analogs thereof Salts and their lake pigments (as rake agents, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.) metal salts of higher fatty acids Diorganotin oxides such as dibutyltin oxide, dioctyltin oxide and dicyclohexyltin oxide; diorganotin borates such as dibutyltin borate, dioctyltin borate and dicyclohexyltin borate; guani Emissions compounds, imidazole compounds.
In particular, for a negatively chargeable toner, an effect is exhibited by increasing the chargeability of the toner by adding an imidazole compound to the resin coating layer of the developer carrying member.

  In particular, among the imidazole compounds, the following general formula (101) or (102)

[Wherein, R ₁ and R ₂ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, and R ₁ and R ₂ may be the same or different. R ₃ and R ₄ represent a linear alkyl group having 3 to 30 carbon atoms, and R ₃ and R ₄ may be the same. ]

[Wherein, R ₅ and R ₆ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, and R ₅ and R ₆ may be the same. R ₇ represents a linear alkyl group having 3 to 30 carbon atoms. ]
Is more preferable in terms of quick and uniform chargeability of the toner and strength of the coating layer.

  Further, it is also possible to add a polymer obtained by copolymerizing a monomer having a polar group to a base monomer and polymerizing it to an appropriate molecular weight to the resin coating layer and use it as a resin control agent.

  For example, the negatively chargeable resin control agent includes a copolymer of at least a vinyl polymerizable monomer and a sulfonic acid-containing acrylamide monomer. More specifically, as the vinyl polymerizable monomer, styrene, α-methylstyrene, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl methacrylate, cyclohexyl (Meth) acrylate, dimethyl (amino) ethyl methacrylate, diethyl (amino) methacrylate, hydroxyethyl (meth) acrylate, (meth) acrylic acid, vinyl acetate, vinyl propionate, etc., these may be used alone or in combination of two or more Can be used for polymerization. Preferably, a copolymer obtained by polymerizing a combination of styrene and an acrylic ester or methacrylic ester is used.

  Examples of the sulfonic acid-containing acrylamide monomer include 2-acrylamidopropanesulfonic acid, 2-acrylamide-n-butanesulfonic acid, 2-acrylamide-n-hexanesulfonic acid, 2-acrylamide-n-octanesulfonic acid, 2 1-acrylamide-n-dodecanesulfonic acid, 2-acrylamide-n-tetradecanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-acrylamido-2-phenylpropanesulfonic acid, 2-acrylamido-2,2,4 -Trimethylpentanesulfonic acid, 2-acrylamido-2-methylphenylethanesulfonic acid, 2-acrylamido-2- (4-chlorophenyl) propanesulfonic acid, 2-acrylamido-2-carboxymethylpropanesulfonic acid, 2-acrylic acid Amido-2- (2-pyridyl) propanesulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 3-acrylamido-3-methylbutanesulfonic acid, 2-methacrylamide-n-decanesulfonic acid, 2-methacrylamide -N-tetradecanesulfonic acid etc. can be mentioned. Preferably, 2-acrylamido-2-methylpropanesulfonic acid is used.

  Further, the positively chargeable resin control agent includes at least a copolymer of a vinyl polymerizable monomer and a nitrogen-containing vinyl monomer. More specifically, typical examples of nitrogen-containing vinyl monomers include p-dimethylaminostyrene, dimethylaminomethyl acrylate, dimethylaminoethyl acrylate, dimethylaminopropyl acrylate, diethylaminomethyl acrylate, diethylaminoethyl acrylate, dimethylaminomethyl methacrylate, Dimethylaminomethyl methacrylate, dimethylaminopropyl methacrylate, diethylaminomethyl methacrylate, diethylaminoethyl methacrylate, N-vinylimidazole, N-vinylbenzimidazole, N-vinylcarbazole, N-vinylpyrrole, N-vinylpiperidine, N- There are nitrogen-containing heterocyclic N-vinyl compounds such as vinylmorpholine and N-vinylindole. In particular, a nitrogen-containing vinyl monomer represented by the following general formula such as dimethylaminoethyl methacrylate or diethylaminoethyl methacrylate or a quaternary ammonium group-containing vinyl monomer is preferably used.

_{[Where, R 1, R 2, R} 3, R 4 represents a hydrogen atom or a saturated hydrocarbon group having 1 to 4 carbon atoms, n is an integer of 1-4. ]
The structure of the quaternary ammonium group-containing vinyl monomer used in the present invention is not particularly limited as long as it is copolymerizable with a vinyl polymerizable monomer. Is a quaternary ammonium group-containing vinyl monomer represented by the following general formula (2).

[Wherein, R ₅ represents a hydrogen atom or a methyl group, R ₆ represents an alkylene group having 1 to 4 carbon atoms, R ₇ to R 9 represent a methyl group, an ethyl group, or a propyl group, and X ₁ represents , —COO— or —CONH—, and A ⁻ represents an anion such as C 1 ⁻ , (1/2) SO ₄ ²⁻ . ]
The surface roughness of the coating layer on the surface of the developer carrying member preferably used in the present invention is in the range of 0.3 to 3.5 μm in terms of JIS centerline average roughness (Ra). It is preferable. More preferably, it is 0.4-2.5 micrometers. If Ra is less than 0.3 μm, the charge amount of the toner on the developer carrying member becomes too high, the developability is lowered, the transportability of the developer to the development area is lowered, and a sufficient image density is obtained. It becomes difficult. On the other hand, if Ra exceeds 3.5 μm, unevenness is likely to occur in the thickness of the toner coat layer formed on the developer carrying member, and this tends to cause unevenness in density on the image.

  Next, a developing device having the developer carrying member of the present invention will be described.

  FIG. 6 is a schematic diagram of a developing device according to an embodiment having the developer carrying member of the present invention.

  In FIG. 6, an electrostatic latent image holding body that holds an electrostatic latent image formed by a known process, for example, an electrophotographic photosensitive drum 501 is rotated in the arrow B direction. A developing sleeve 508 as a developer carrying member carries a one-component developer having magnetic toner supplied to a developing container 503 and rotates in the direction of arrow A, whereby the developing sleeve 508 and the photosensitive drum 501 are moved. The developer is transported to the development area D that faces the developer. As shown in FIG. 8, in the developing roller 510, a magnet (magnet roller) 509 is disposed in the developing sleeve 508 in order to magnetically attract and hold the developer on the developing sleeve 508.

  A developing sleeve 508 used in the developing device has a conductive resin coating layer 507 coated on a metal cylindrical tube 506 as a base. Developer is fed into the developer container 503 from a developer supply container (not shown) via a developer supply member (such as a screw) 512. The developer container is divided into a first chamber 514 and a second chamber 515, and the developer fed into the first chamber 514 passes through a gap formed by the developer container 503 and the partition member 514 by the stirring and conveying member. It is sent to the second chamber 515. The developer is carried on the developing sleeve 508 by the action of magnetic force by the magnet roller 509. In the second chamber 515, a stirring member 511 for preventing the developer from staying is provided.

  The developer obtains a triboelectric charge capable of developing the electrostatic latent image on the photosensitive drum 501 by friction between the magnetic toner and the conductive coating layer 507 on the developing sleeve 508. In the example of FIG. 6, in order to regulate the layer thickness of the developer conveyed to the development region D, a magnetic regulation blade 502 made of a ferromagnetic metal as a developer layer thickness regulating member is provided approximately from the surface of the developing sleeve 508. It is suspended from the hopper 503 so as to face the developing sleeve 508 with a gap width of 50 to 500 μm. A magnetic force line from the magnetic pole N <b> 1 of the magnet roller 509 concentrates on the magnetic regulation blade 502, so that a thin layer of developer is formed on the developing sleeve 508. In the present invention, a nonmagnetic blade can be used instead of the magnetic regulating blade 502. In this way, the thickness of the thin developer layer formed on the developing sleeve 508 is preferably thinner than the minimum gap between the developing sleeve 508 and the photosensitive drum 501 in the developing region D.

  The developer carrying member of the present invention is particularly effective when incorporated in a developing device that develops an electrostatic latent image with a thin layer of the developer as described above, that is, a non-contact developing device. In D, the developer carrying member of the present invention can be applied to a developing device in which the thickness of the developer layer is equal to or greater than the minimum gap between the developing sleeve 508 and the photosensitive drum 501, that is, a contact type developing device. .

  In order to avoid complicated description, the following description will be made by taking the non-contact developing device as described above as an example. A developing bias voltage is applied to the developing sleeve 508 by a developing bias power source 513 as a biasing unit in order to cause the one-component developer having magnetic toner carried on the developing sleeve 508 to fly. When a DC voltage is used as the developing bias voltage, the developing sleeve 508 has a voltage value between the potential of the image portion of the electrostatic latent image (the region visualized as the developer adheres) and the background portion. It is preferable to apply to. In order to increase the density of the developed image or improve the gradation, an alternating bias voltage may be applied to the developing sleeve 508 to form an oscillating electric field whose direction is alternately reversed in the developing region D. . In this case, it is preferable to apply to the developing sleeve 508 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 regular development, toner that is charged with the opposite polarity to the polarity of the electrostatic latent image is used for visualization by attaching toner to the high potential portion of the electrostatic latent image having a high potential portion and a low potential portion. To do. In the case of reversal development in which toner is attached to a low potential portion of an electrostatic latent image having a high potential portion and a low potential portion for visualization, a toner charged with the same polarity as the polarity of the electrostatic latent image is used. High potential and low potential are expressed in absolute values. In any of these cases, the developer is charged by friction with at least the surface of the developing sleeve 508 (conductive coating layer 507).

  FIG. 6 shows an example of a magnetic blade disposed away from the developing sleeve as the developer layer thickness regulating member that regulates the layer thickness of the developer on the developing sleeve 508. As shown in FIG. , An elastic regulating blade made of an elastic plate made of a material having rubber elasticity such as urethane rubber or silicone rubber, or a material having metal elasticity such as phosphor bronze or stainless steel is used. It may be used in contact or pressure contact via a developer.

  In the type of developing device in which the layer thickness regulating blade 516 is in contact with or pressed against, the developer layer forms a thin layer of the developer on the developing sleeve while being subjected to stronger regulation. A thinner developer layer can be formed than in the case of the sixth reference example.

  FIGS. 6 and 7 are merely schematic illustrations of the developing device of the present invention. In addition to the layer thickness regulating member described above, the shape of the developing container 503 (hopper), the presence or absence of stirring blades 505 and 511, Needless to say, there are various forms such as the arrangement of the magnetic poles, the shape of the supply member 512, and the presence or absence of a replenishing container.

  Next, the developer used in the developing device of the present invention will be described.

  The toner is a fine powder in which a resin, a release agent, a charge control agent, a colorant and the like are mainly melt-kneaded, solidified, pulverized, and then classified to obtain a uniform particle size distribution. As the binder resin used for the toner, generally known resins can be used.

  For example, styrene such as styrene, α-methylstyrene, p-chlorostyrene, and homopolymers of substituted styrene; styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-ethyl acrylate copolymer, styrene -Butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer Polymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid Copolymer, styrene-maleic acid Styrenic copolymer such as ter copolymer; polymethyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, temper resin, phenol resin, aliphatic or fat Examples thereof include cyclic hydrocarbon resins, aromatic petroleum resins, paraffin wax, and carnauba wax. These can be used alone or in combination.

  The toner may contain a pigment. For example, carbon black, nigrosine dye, lamp black, Sudan black SM, first yellow G, benzidine yellow, pigment yellow, Indian first orange, irgadin red, paranitroaniline red, toluidine red, carmine FB, Permanent Bordeaux FRR, Pigment Orange R, Risor Red 2G, Lake Red C, Rhodamine FB, Rhodamine B Lake, Methyl Bio Red B Lake, Phthalocyanine Blue, Pigment Blue, Brilliant Green B, Phthalocyanine Green, Oil Yellow GG, Pomelo First Yellow CGG, Kaya Set Y963, Kaya Set YG, Pomelo First Orange RR, Oil Scarlet, Orazole Bra Down B, pomelo First Scarlet CG, Oil Pink OP, and the like.

  In order to use the toner as a magnetic toner, a magnetic powder is contained in the toner. As such magnetic powder, a substance that is magnetized in a magnetic field is used, and there are 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% by weight with respect to the toner weight.

  Waxes can be incorporated into the toner for the purpose of improving releasability during fixing and improving fixing properties. Examples of such waxes include paraffin wax and derivatives thereof, microcrystalline wax and derivatives thereof, Fischer Tropus wax and derivatives thereof, polyolefin wax and derivatives thereof, carnauba wax and derivatives thereof, and the derivatives include oxides, Includes block copolymers with vinyl monomers and graft modified products. In addition, alcohols, fatty acids, acid amides, esters, ketones, hydrogenated castor oil and derivatives thereof, plant waxes, animal waxes, mineral waxes, petrolactams, and the like can also be used.

  If necessary, the toner may contain a charge control agent. Charge control agents include negative charge control agents and positive charge control agents. For example, there are the following substances that control the toner to be negatively charged. For example, organometallic 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 metal salts thereof, anhydrides, esters, and phenol derivatives such as bisphenol. Examples of substances for positively charging the toner include the following. Modified products with nigrosine and fatty acid metal salts, etc., quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and oniums such as phosphonium salts which are analogs thereof Salts and their lake pigments (including phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.) Diorganotin oxides such as dibutyltin oxide, dioctyltin oxide and dicyclohexyltin oxide; diorganotin borates such as dibutyltin borate, dioctyltin borate and dicyclohexyltin borate; guani Emissions compounds, imidazole compounds.

  The toner is used by externally adding a powder such as an inorganic fine powder for the purpose of improving fluidity, if necessary. Examples of such fine powder 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 organosilicon compound, a titanium coupling agent or the like. Examples of organosilicon compounds include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyl. Dimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, Diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, Examples include 1,3-diphenyltetramethyldisiloxane, and dimethylpolysiloxane having 2 to 12 siloxane units per molecule, each containing a hydroxyl group bonded to one Si at a terminal unit. Moreover, you may use what processed the untreated fine powder with the nitrogen-containing silane coupling agent. In particular, a positive toner is preferable. Examples of such treating agents include aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane, dibutylaminopropyltrimethoxysilane, Monobutylaminopropyltrimethoxysilane, dioctylaminopropyltrimethoxysilane, dibutylaminopropyldimethoxysilane, dibutylaminopropylmonomethoxysilane, dimethylaminophenyltrimethoxysilane, trimethoxysilyl-γ-propylphenylamine, trimethoxysilyl-γ -Propylbenzylamine, trimethoxysilyl-γ-propylpiperidine, trimethoxysilyl-γ-propylmorpholine, tri There are Tokishishiriru -γ- propyl imidazole.

  Examples of methods for treating inorganic fine powder with the silane coupling agent include 1) spray method, 2) organic solvent method, and 3) aqueous solution method. In general, the treatment by the spray method is a method of stirring a pigment, spraying an aqueous solution or solvent solution of a coupling agent, and then removing the water or solvent at about 120 to about 130 ° C. and drying. The treatment by the organic solvent method is to dissolve a coupling agent in an organic solvent (alcohol, benzene, halogenated hydrocarbon, etc.) containing a hydrolysis catalyst together with a small amount of water, and to immerse the pigment in this, Solid-liquid separation is performed by filtration or pressing and dried at about 120 to about 130 ° C. In the aqueous solution method, a coupling agent of about 0.5% is hydrolyzed in water of a constant pH or water-solvent, and after pigment is immersed therein, solid-liquid separation is similarly performed and dried. .

It is also possible to use fine powder treated with silicone oil as another organic treatment. Preferred silicone oils are those having a viscosity at 25 ° C. of about 0.5 to 10000 mm ² / s, preferably 1 to 1000 mm ² / s. For example, methyl hydrogen silicone oil, dimethyl silicone oil, phenyl methyl silicone oil Chlorophenylmethyl silicone oil, alkyl-modified silicone oil, fatty acid-modified silicone oil, polyoxyalkylene-modified silicone oil, fluorine-modified silicone oil, and the like. Moreover, you may use the silicone oil which has a nitrogen atom in a side chain. In particular, a positive toner is preferable. The treatment with silicone oil can be performed, for example, as follows. The pigment is vigorously disturbed while heating as necessary, and the silicone oil or solution thereof is sprayed or vaporized and sprayed, or the pigment is made into a slurry, and the silicone oil or It can be easily treated by dropping the solution. These silicone oils are used singly or as a mixture of two or more or in combination or multiple treatments. Moreover, you may use together with the process by a silane coupling agent. Such a toner is preferably used after being subjected to a spheroidizing treatment and a surface smoothing treatment by various methods. As such a method, an apparatus having a stirring blade or a blade, and a liner or a casing, for example, smoothes the surface by a mechanical force when passing toner through a minute gap between the blade and the liner. Or a method of spheroidizing the toner, a method of suspending the toner in warm water to spheroidize, a method of exposing the toner to a hot air stream and spheroidizing. In addition, as a method for directly producing a 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 in a single amount. After forming the body composition, the monomer composition is dispersed in a continuous layer containing a dispersion stabilizer, for example, an aqueous phase with an appropriate stirrer, and further subjected to a polymerization reaction to obtain a desired composition. This is a method for obtaining a developer having a particle size of.

(Example)
Next, the present invention will be described in more detail with specific examples.

Example 1
A resin composition was prepared as follows.
-250 mass parts of phenol resin intermediate having a weight average molecular weight Mw = 1800-100 mass parts of crystalline graphite having a number average particle diameter of 2.5 µm-250 mass parts of methanol-100 mass parts of isopropyl alcohol Using these materials with glass beads The resulting mixture was dispersed by a horizontal continuous sand mill. When the particle size distribution of the coating material solution A was measured, the number average particle size was 1.9 μm.
-Paint stock solution A 700 parts by mass-Boron carbide 100 parts by mass (number average particle size 3.0 μm, SF-1 = 0.64, resistance 0.5 Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
-Isopropyl alcohol 540 mass parts The coating material 1 of the said composition was created. 100 parts by weight of boron carbide and 270 parts by weight of isopropyl alcohol are added to the coating material solution A, dispersed using a vertical sand mill using glass beads, and the remaining isopropyl alcohol and 30 parts by weight of spherical carbon particles are further added. Added dispersion. The paint was passed through 250 and 450 mesh sieves. The viscosity of this paint 1 was 75 mPa · s. A development sleeve workpiece having an outer diameter of 24.5 mmφ, a surface roughness Ra = 0.2 μm, and a runout of 10 μm or less was prepared by centerless processing of an aluminum cylindrical tube having a development sleeve flange on one side. The work was placed upright on a turntable, rotated while masking both ends of the sleeve, and the paint 1 was sprayed onto the work at a constant speed with a spray gun to obtain an application sleeve. This coating sleeve was put into a 150 ° C. ventilated dryer for 30 minutes, and the paint was dried and cured to form a resin surface layer. At this time, the thickness of the resin coating layer was 12.5 μm, the surface roughness was Ra = 1.25 μm, and the volume resistance value of the coating layer was 0.95 Ω · cm.

A magnetic roller was attached to the developing sleeve, and a stainless steel flange was fitted to form a developing roller. This developing roller can be mounted on a modified IR-3300 (digital copying machine) manufactured by Canon Inc. Further, the developing device was modified so that an elastic regulating blade as schematically shown in FIG. 7 could be attached, and the elastic blade was brought into elastic contact with the developing sleeve. As the elastic blade, a silicone rubber blade in which silica was dispersed in silicone rubber was used. The sleeve / drum peripheral speed ratio was about 1.15. Image evaluation was performed using the magnetic toner shown below. 5,000 images are continuously printed in 3 environments of L / L (23 ° C / 10% RH), N / N (23 ° C / 60% RH), H / H (30 ° C / 80% RH) The image performance was compared. In N / N, continuous durability up to 100,000 sheets was carried out, and durability was confirmed.
Styrene-butyl acrylate resin 100 parts by mass Magnetite 90 parts by mass Hydrocarbon wax 3 parts by mass Azo-based iron complex compound (negative charge control agent) 2 parts by mass The above materials were dispersed and mixed with a Henschel mixer and then heated to 130 ° C. The mixture was melt-kneaded with a biaxial extruder, and the cooled kneaded product was coarsely pulverized with a cutter mill. The coarsely pulverized product was finely pulverized using a mechanical pulverizer having a rotor and a liner, and the obtained finely pulverized product was classified with an air classifier to obtain toner fine particles having a mass average particle diameter of 7.5 μm. Further, a spheronization treatment was performed by a spheronization apparatus having a liner and a rotor type blade, and having a gap between the liner and the blade of 2 mm. The particle size distribution of the resulting magnetic toner fine particles was 12.1% for the number average particle diameter of 7.2 μm, 4.0 μm or less, and 1.1% for the mass of 12.7 μm or more. . To 100 parts by mass of this magnetic toner, 0.8 part by mass of colloidal silica treated with a silane coupling agent and further treated with silicone oil and 4 parts by mass of strontium titanate fine particles were externally added using a Henschel mixer. The resultant mixture was used as a one-component magnetic developer.

The results are shown in Tables 1-3.
Physical property measurement method and image evaluation method Measurement method (1) Measurement of surface roughness The arithmetic average roughness (Ra) indicates the arithmetic average roughness Ra measured according to JISB0601 (2001), and the surface roughness in the present invention. Is measured by using a surface roughness meter SE-3500 manufactured by Kosaka Laboratories, and the measurement conditions are 9 measurements at a cut-off λc of 0.8, an evaluation length of 4.0 mm, and a feed rate of 0.5 mm / sec. Averaged values were taken.

(2) Measurement of volume resistance of coating layer A coating layer having a thickness equivalent to that of the resin coating layer is formed on a 100 μm thick PET sheet, and ASTM Standard (D-991-82) and Japan Rubber Association Standard Standard It measured using the voltage drop type digital ohm meter (made by Kawaguchi Electric Mfg. Co., Ltd.) which provided the electrode of the 4-terminal structure for volume resistance resistance measurement of conductive rubber and plastics based on SRIS (2301-1969). The measurement environment is 20 to 25 ° C. and 50 to 60 RH%.

(3) Particle size measurement of graphite / carbon particles and paint The particle size is measured using a Coulter LS-230 type particle size distribution meter (manufactured by Coulter, Inc.) of a laser diffraction type particle size distribution meter. As a measuring method, a circulation module for organic solvent is used, and isopropyl alcohol is used as a measuring solvent. Wash the measurement system of the particle size distribution analyzer with isopropyl alcohol for about 5 minutes and execute the background function.

  Next, 5 to 25 mg of a measurement sample is added to 10 ml of isopropyl alcohol. The isopropyl alcohol solution in which the sample is suspended is subjected to a dispersion process for about 1 to 3 minutes with an ultrasonic disperser to obtain a sample solution, and the sample solution is gradually added to the measurement system of the measurement device, and the sample screen is displayed. The sample concentration in the measurement system is adjusted so that PIDS is 45 to 55%. As the refractive index of the solvent, 1.379 of isopropyl alcohol is used, and as the refractive index of the sample, an optical model having a real part 1.5 and an imaginary part 0.3 is prepared and used. Measurement is performed, and the number average particle diameter and volume average particle diameter calculated from the number distribution are obtained.

(4) Particle size measurement of inorganic particles The particle size of inorganic particles is measured using an electron microscope. The shooting magnification is 1,000 to 10,000 times. Measure the primary particle size on the photo. At this time, the major axis and the minor axis are measured, and the average value is defined as the particle size. This is measured for 100 samples, and the 50% value is taken as the average particle size. The coarse particles were also confirmed by the same method, and it was confirmed that there was substantially no difference in numerical value from the measurement result by the LS230.

(5) Measurement of Toner Particle Size Particle size was measured using a Coulter Counter Multisizer II (manufactured by Coulter Co., Ltd.), and a mass-based mass average diameter and distribution derived from the volume distribution were determined.

(6) Measurement of film thickness (scrap amount) of resin coating layer A laser dimension measuring device manufactured by KEYENCE Corp. was used. Using the controller LS-5500 and the sensor head LS-5040T, the sensor unit was separately fixed to an apparatus equipped with a sleeve fixing jig and a sleeve feeding mechanism, and the average value of the outer diameter of the sleeve was measured. The measurement was divided into 30 with respect to the longitudinal direction of the sleeve and measured at 30 points. Further, after rotating the sleeve by 90 ° in the circumferential direction, measurements were further made at 30 points, a total of 60 points, and the average value was taken. The outer diameter of the sleeve before application of 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 taken as the coating film thickness and the amount of abrasion.

(7) Measurement of SF-1 Measurement was performed using a multi-image analyzer (manufactured by Beckman Coulter).
Average circularity SF-1 is the following equation (1): Circularity = (4 × A) / {(ML) 2 × π} (1)
[In the formula, ML represents the maximum length of the Pythagorean method of the particle projection image, and A represents the area of the particle projection image. ]
It means the average value of circularity obtained. Specifically, the graphitized particle projection image magnified by the optical system is taken into an image analysis device, the circularity value of each particle is calculated, and these are averaged. In the present invention, reliability is obtained as an average value, and the circularity is measured by limiting to a particle range having an equivalent circle diameter of 2 μm or more, which has a great influence on the properties of the resin coating layer. In order to obtain the reliability of these values, the number of measured particles is about 3000 or more, preferably 5000 or more.

Evaluation Method (1) Image Density A copy image density of a 5 mmφ black circle on a test chart with an image ratio of 5.5% is measured with a reflection densitometer RD918 (manufactured by Macbeth), and an average value of five points is taken. Concentration. The reflection density is preferably 1.20 or more, more preferably 1.30 or more, and is satisfactory if it is 1.40. From 1.00 to 1.20, solids and halftones become blurry, and when it is 1.00 or less, blurring also stands out in lines such as characters.

(2) Fog Measure the reflectance of a solid white image under development suitability conditions, and further measure the reflectance of unused transfer paper. (Worst value of reflectance of solid white image-Reflectance of unused transfer paper The highest value was defined as the fog density. The reflectance was measured with TC-6DS (manufactured by Tokyo Denshoku). Here, when the measured value is judged visually, 1.5 or less is a level that can hardly be visually confirmed, about 2.0 to 3.0 is a level that can be confirmed by looking closely, and if it exceeds 4.0, it is fogged at a glance. Is a level that can be confirmed.

(3) Toner charge amount (Q / M) and toner transport amount (M / S)
The toner carried on the developing sleeve is sucked and collected by a metal cylindrical tube and a cylindrical filter. At that time, the charge amount Q stored in the condenser, the collected toner mass M, and the toner are sucked through the metal cylindrical tube. From the area S, the charge amount Q / M (mC / kg) per unit mass and the toner mass M / S (dg / m ² ) per unit area are calculated, and the toner charge amount (Q / M) and toner transport are calculated respectively. Amount (M / S).

(4) Halftone uniformity (fading)
The band-shaped density fading (fading) that occurs in the halftone or solid, particularly in the image traveling direction, is evaluated by the following index.
A: The image cannot be confirmed.
BA: Although it can be confirmed slightly when looking well, it is hardly confirmed at first glance.
B: Slightly confirmed with halftone, but no problem with solid black.
BC: Level that can be confirmed with halftone but only slightly with solid black.
C: A difference in shading can be confirmed even in a solid black image.
D: The density difference is conspicuous throughout the solid black image.
E: An image having a low density and a wide fading range.

(5) Sleeve ghost After flowing solid white during image endurance, place a solid black bold letter or hieroglyph image on the white for the entire circumference of the sleeve of the image chart, and use the image chart with the rest as halftone. It was evaluated how much ghosting of bold characters and hieroglyphics occurred on the tone.
A: No ghost.
BA: A slight difference in density is observed, but good B: A slight difference in density can be confirmed, but there is no problem level BC: Intermediate level between B and C C: Slight ghost is noticeable. Within practical level.
N1: Negative ghost (thin ghost part) which is a problem in practical use comes out for one turn of the sleeve P1: Positive coast which is a problem in practical use (dark ghost part) comes out for one turn of the sleeve N2: Problem in practical use The negative ghost that comes out more than two sleeve laps P2: The positive coast that is a problem in practical use comes out more than two sleeves (6) Blade scratches Scratches generated on the regulation blade and on the halftone and solid images due to the scratches Appearing streaks were evaluated according to the following rank.
A: There is almost no scratch on the blade.
B: Shallow scratches that have some scratches on the blade but are not confirmed in the image.
C: Practically acceptable as long as it can be slightly confirmed on a halftone image at a position corresponding to a scratch on the blade.
D: A streak is clearly seen on a halftone image, which may cause a practical problem. Or the level at which multiple lines are observed in a halftone image.
E: Can be discriminated even when the lines are solid black. Or, a level where many stripes are observed in halftone.

Example 2
-Paint stock solution A 700 parts by mass-Boron carbide 100 parts by mass (number average particle diameter 3.2 μm, SF-1 = 0.54, resistance 0.5 Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
-Isopropyl alcohol 540 mass parts The coating material 2 of the said composition was created. The dispersing method was in accordance with Example 1. The viscosity of this paint 2 was 77.5 mPa · s. Using the same work as in Example 1, a resin coating layer was formed by the same operation. At this time, the resin coating layer had a thickness of 12.5 μm, a surface roughness Ra = 1.20 μm, and a volume resistance of 0.96 Ω · cm. In the same manner as in Example 1, this developing sleeve was a developing roller that can be attached to a modified IR-3300 machine. Further, the same evaluation as in Example 1 was performed. The results are shown in Tables 1-3.

  In the following Examples 3 to 19 and Comparative Examples 1 to 6, creation of a developing sleeve (resin coating layer), development of a developing roller, and image evaluation were performed in the same manner. The results are shown in Tables 1-3. Further, Table 4 shows the coating layer thickness, surface roughness Ra, volume resistance, and paint viscosity.

Example 3
-Paint stock solution A 700 parts by mass-Boron carbide 50 parts by mass (number average particle size 6.5 μm, SF-1 = 0.65, resistance 0.5 Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 450 parts by mass

Comparative Example 1
-Paint stock solution A 700 parts by mass-Boron carbide 100 parts by mass (number average particle size 1.0 µm, SF-1 = no measurement, resistance 0.5 Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 540 parts by mass

Comparative Example 2
-Paint stock solution A 700 parts by mass-Spherical carbon particles 35 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ 365 parts by mass of isopropyl alcohol

Example 4
-Paint stock solution A 700 parts by mass-Titanium nitride 100 parts by mass (number average particle size 2.3 μm, SF-1 = 0.64, resistance 4 × 10 ⁻⁵ Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 540 parts by mass

Comparative Example 3
-Paint stock solution A 700 parts by mass-Titanium nitride 100 parts by mass (number average particle size 0.5 μm, SF-1 = no measurement, resistance 4 × 10 ⁻⁵ Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 540 parts by mass

Comparative Example 4
-Paint stock solution A 700 parts by mass-Boron carbide 40 parts by mass (number average particle size 9.5 μm, SF-1 = 0.61, resistance 0.5 Ω · cm)
-Spherical carbon particles 40 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 6.5 μm)
・ Isopropyl alcohol 450 parts by mass

Comparative Example 5
-Paint stock solution A 700 parts by mass-Boron carbide 100 parts by mass (number average particle size 6.5 μm, SF-1 = 0.65, resistance 0.5 Ω · cm)
・ 485 parts by mass of isopropyl alcohol

Example 5
-Paint stock solution A 700 parts by mass-Boron carbide 100 parts by mass (number average particle size 3.0 μm, SF-1 = 0.64, resistance 0.5 Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
10 parts by mass of an imidazole compound of the general formula (101) (R ₁ , R ₂ : CH ₃ , R ₃ , R ₄ : n-C ₁₁ H ₂₃ )
・ Isopropyl alcohol 560 parts by mass

Example 6
-Paint stock solution A 700 parts by mass-Boron carbide 75 parts by mass (number average particle size 3.0 μm, SF-1 = 0.64, resistance 0.5 Ω · cm)
25 parts by mass of aluminum borate (number average particle diameter 2.6 μm, SF-1 = 0.73, resistance value about 10 ¹³ Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 540 parts by mass

Example 7
-Paint stock solution A 700 parts by mass-Boron carbide 75 parts by mass (number average particle diameter 3.2 μm, SF-1 = 0.54, resistance 0.5 Ω · cm)
25 parts by mass of aluminum borate (number average particle diameter 2.6 μm, SF-1 = 0.73, resistance value about 10 ¹³ Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 540 parts by mass

Example 8
-Paint stock solution A 700 parts by mass-Boron carbide 60 parts by mass (number average particle size 3.0 μm, SF-1 = 0.64, resistance 0.5 Ω · cm)
40 parts by mass of aluminum oxide (number average particle size 3.5 μm, SF-1 = 0.70, resistance value about 10 ¹⁴ Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 540 parts by mass

Example 9
-Paint stock solution A 700 parts by mass-Boron carbide 60 parts by mass (number average particle size 3.0 μm, SF-1 = 0.64, resistance 0.5 Ω · cm)
40 parts by mass of aluminum oxide (number average particle diameter 3.2 μm, SF-1 = 0.57, resistance value about 10 ¹⁴ Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 540 parts by mass

Example 10
-Paint stock solution A 700 parts by mass-Boron carbide 60 parts by mass (number average particle diameter 3.2 μm, SF-1 = 0.54, resistance 0.5 Ω · cm)
40 parts by mass of aluminum oxide (number average particle diameter 3.2 μm, SF-1 = 0.57, resistance value about 10 ¹⁴ Ω · cm)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 540 parts by mass

Example 11
-Paint stock solution A 700 parts by mass-Boron carbide 85 parts by mass (number average particle size 3.0 μm, SF-1 = 0.64, resistance 0.5 Ω · cm)
15 parts by mass of aluminum borate (number average particle size 2.6 μm, SF-1 = 0.73, resistance value about 10 ¹³ Ω · cm)
10 parts by mass of an imidazole compound of the general formula (101) (R ₁ , R ₂ : CH ₃ , R ₃ , R ₄ : n-C ₁₁ H ₂₃ )
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 560 parts by mass

Example 12
-Paint stock solution A 700 parts by mass-Boron carbide 85 parts by mass (number average particle size 3.0 μm, SF-1 = 0.64, resistance 0.5 Ω · cm)
15 parts by mass of aluminum borate (number average particle size 2.6 μm, SF-1 = 0.73, resistance value about 10 ¹³ Ω · cm)
10 parts by mass of an imidazole compound of the general formula (102) (R ₅ , R ₆ : H, R ₇ : CH 3)
・ Spherical carbon particles 30 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 10.0 μm)
・ Isopropyl alcohol 560 parts by mass

Comparative Example 6
-Paint stock solution A 700 parts by mass-Boron carbide 60 parts by mass (number average particle size 9.5 μm, SF-1 = 0.61, resistance 0.5 Ω · cm)
40 parts by mass of aluminum borate (number average particle size 2.6 μm, SF-1 = 0.73, resistance value about 10 ¹³ Ω · cm)
・ 485 parts by mass of isopropyl alcohol

Example 13
-Paint stock solution A 700 parts by mass-Boron carbide 50 parts by mass (number average particle diameter 2.1 μm, SF-1 = 0.67, resistance 0.5 Ω · cm)
・ Spherical carbon particles 60 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 6.5 μm)
・ Isopropyl alcohol 505 parts by mass

Example 14
-Paint stock solution A 700 parts by mass-Boron carbide 50 parts by mass (number average particle diameter 2.1 μm, SF-1 = 0.67, resistance 0.5 Ω · cm)
・ Spherical carbon particles 60 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 6.5 μm)
10 parts by mass of an imidazole compound of the general formula (101) (R ₁ , R ₂ : CH ₃ , R ₃ , R ₄ : n-C ₁₁ H ₂₃ )
・ 525 parts by mass of isopropyl alcohol

Example 15
-Paint stock solution A 700 parts by mass-Boron carbide 50 parts by mass (number average particle size 2.4 μm, SF-1 = 0.55, resistance 0.5 Ω · cm)
・ Spherical carbon particles 60 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 6.5 μm)
・ Isopropyl alcohol 505 parts by mass

Comparative Example 7
-Paint stock solution A 700 parts by mass-Boron carbide 100 parts by mass (number average particle size 1.0 µm, SF-1 = no measurement, resistance 0.5 Ω · cm)
・ Spherical carbon particles 60 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 6.5 μm)
・ 595 parts by mass of isopropyl alcohol

Example 16
-Paint stock solution A 700 parts by mass-Boron carbide 75 parts by mass (number average particle size 2.1 μm, SF-1 = 0.67, resistance 0.5 Ω · cm)
25 parts by mass of aluminum borate (number average particle diameter 2.6 μm, SF-1 = 0.73, resistance value about 10 ¹³ Ω · cm)
・ Spherical carbon particles 60 parts by mass (spherical carbon particles whose surface is graphitized, number average particle size 6.5 μm)
・ 595 parts by mass of isopropyl alcohol

Example 17
-Paint stock solution A 700 parts by mass-Boron carbide 75 parts by mass (number average particle size 2.1 μm, SF-1 = 0.67, resistance 0.5 Ω · cm)
25 parts by mass of aluminum borate (number average particle diameter 2.6 μm, SF-1 = 0.73, resistance value about 10 ¹³ Ω · cm)
・ Spherical carbon particles 23 parts by mass (spherical carbon particles whose surface is graphitized, number average particle diameter 15.4 μm)
・ Isopropyl alcohol 530 parts by mass

Example 18
-Paint stock solution A 700 parts by mass-Boron carbide 75 parts by mass (number average particle size 2.1 μm, SF-1 = 0.67, resistance 0.5 Ω · cm)
25 parts by mass of aluminum borate (number average particle diameter 2.6 μm, SF-1 = 0.73, resistance value about 10 ¹³ Ω · cm)
-Spherical carbon particles 15 parts by mass (spherical carbon particles whose surface is graphitized, number average particle diameter 22.3 μm)
・ Isopropyl alcohol 515 parts by mass

Example 19
-Paint stock solution A 700 parts by mass-Boron carbide 75 parts by mass (number average particle size 2.1 μm, SF-1 = 0.67, resistance 0.5 Ω · cm)
25 parts by mass of aluminum borate (number average particle diameter 2.6 μm, SF-1 = 0.73, resistance value about 10 ¹³ Ω · cm)
-10 parts by mass of spherical carbon particles (spherical carbon particles whose surface is graphitized, number average particle size 29.5 μm)
・ Isopropyl alcohol 505 parts by mass

  From the above examination results, in Comparative Example 2, an image having no problem in practical use can be obtained in the durability of at least 5,000 or 20,000, but as can be seen from Table 1-2, 50,000 In the durability exceeding 1, the image deteriorates due to scraping of the coating layer. In terms of appearance, it appears in the amount of shaving, base exposure, and surface roughness. On the other hand, as in Example 1, by adding conductive inorganic particles, the amount of shaving is reduced, the surface roughness is reduced, and the durability of the coating layer is improved, so that the image does not deteriorate. . Although there is a tendency for the initial image density to rise, the image density level to lower, the fog, and the halftone image to be slightly deteriorated due to the Q / M reduction due to the addition of conductive inorganic particles, the average particle diameter of the conductive inorganic particles is reduced. By setting the thickness to 2 μm or more, the durability is improved and the influence on the frictional charging of the toner can be suppressed as much as possible, so that it does not become a practically problematic level. As seen in Comparative Example 1 and the like, when the conductive inorganic particles are small, the effect of suppressing the abrasion of the coating layer is small, and the charging of the toner is liable to be adversely affected. Therefore, image density reduction, ghost, fog, etc. It tends to cause defects. In addition, when conductive inorganic particles having a large particle diameter capable of roughening the surface as in Comparative Example 5 are used, compared with carbon-based particles used as roughening particles as in Comparative Example 4. When the average particle size of the conductive inorganic particles is large, the blade streaks are deteriorated due to the durability, and the image is hindered.

  Furthermore, when the conductive inorganic particles having a predetermined particle diameter and the charge control agent or charge control resin are used in combination, or by using the insulating inorganic particles that easily give the toner triboelectric charge, the initial image density can be reduced. Start-up, prevention of lowering of image density level, fogging, ghosting, fading deterioration can be suppressed, and even better images can be obtained compared to using conductive inorganic particles alone in addition to carbon-based rough particles. It becomes like this.

It is a schematic diagram which shows an example of the surface of the developing agent carrier which has the conventional resin coating layer. It is a schematic diagram which shows an example of the surface of the developing agent carrier which has the resin coating layer of this invention. It is a schematic diagram which shows another example of the surface of the developing agent carrier which has the resin coating layer of this invention. It is a schematic diagram which shows another example of the surface of the developing agent carrier which has the resin coating layer of this invention. It is a schematic diagram which shows another example of the surface of the developing agent carrier which has the resin coating layer of this invention. FIG. 2 is a schematic diagram illustrating an example of the configuration of a one-component developing device of the present invention. It is a schematic diagram which shows another example of the one-component developing device structure of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Conductive resin coating layer 3 Roughening particle 4 High hardness particle 6 Fine particle 9 Toner

Claims (5)

In a developer carrier used in a developing device that develops an electrostatic latent image formed on an electrostatic latent image carrier with a one-component developer carried on a developer carrier and forms a toner image.
The developer carrier has at least a substrate and a conductive resin coating layer formed on the substrate surface,
The conductive resin coating layer has at least (a) a binder resin resin, and (b) at least a surface for forming irregularities on the conductive resin coating layer. And (c) conductive inorganic particles having a Mohs hardness of 6 or more, a number average particle size of 2 μm or more, and an average particle size smaller than the number average particle size of the unevenness-forming particles. A developer carrier.   The developer carrying member according to claim 1, wherein the conductive resin coating layer further contains (d) a charge control agent.   The resin coating layer further includes (e) insulating inorganic particles having a Mohs hardness of 6 or more, a number average particle size of 2 μm or more, and an average particle size smaller than the number average particle size of the unevenness forming particles. The developer carrying member according to claim 1 or 2, wherein the developer carrying member is provided. A developer containing at least a developer container and a developer carrier for carrying and transporting the developer stored in the container, and forming a developer layer on the developer carrier by a developer regulating member; In a developing device for transporting a developer on a carrier to a developing region facing the electrostatic latent image carrier, developing the electrostatic latent image on the electrostatic latent image carrier with a developer, and forming a toner image ,
The developer carrier has at least a substrate and a conductive resin coating layer formed on the substrate surface,
The conductive resin coating layer has at least (a) a binder resin resin, and (b) at least a surface for forming irregularities on the conductive resin coating layer. And (c) conductive inorganic particles having a Mohs hardness of 6 or more, a number average particle size of 2 μm or more, and an average particle size smaller than the number average particle size of the unevenness-forming particles. A developing device. The developing device according to claim 4, wherein the developer carrying member is the developer carrying member according to claim 2.

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