JP3486538B2 - Developing method, developing device and image forming method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing method for developing a latent image formed on an image carrier used in electrophotography or the like with a developer to visualize the latent image, and particularly to a developer carrier. The present invention relates to a developing method and a developing device, in which a developer thin layer is formed by using a regulating member which is in contact with a developer via the developer and regulates the thickness of the developer layer.

[0002]

2. Description of the Related Art Conventionally, a number of electrophotographic methods are known, but generally, a photoconductive material is used to form an electric latent image on a photoconductor by various means, and then the electrophotographic image is formed. The latent image is developed with toner (developer) to make it a visible image,
After transferring the toner image to a transfer material such as paper, if necessary,
The toner image is fixed on the transfer material by heat, pressure or the like to obtain a copy.

The developing method in electrophotography is mainly divided into a one-component developing method and a two-component developing method. In recent years, since it is necessary to reduce the size of a copying apparatus for the purpose of reducing the weight and size of an electrophotographic apparatus, a developing apparatus using a one-component toner is often used.

Unlike the two-component system, the one-component developing system does not require carrier particles such as glass beads and iron powder, so that the developing device itself can be made compact and lightweight. Furthermore, in the two-component development method, it is necessary to keep the toner concentration in the developer constant,
A device for detecting the toner concentration and supplying a required amount of toner is required. Therefore, also in this case, the developing device becomes large and heavy. Such a device is not necessary in the one-component developing system, and it is preferable because it can be made small and light.

For example, as a developing method using a one-component toner, an electrostatic latent image is formed on the surface of a photosensitive drum as an image bearing member, friction between a developing sleeve as a developer bearing member and toner particles, and / or friction. Is positively or negatively charged to the toner particles by friction between the toner particles and the developer regulating member that regulates the toner application amount on the developing sleeve. The toner is applied thinly on the developing sleeve and the photosensitive drum and the developing sleeve. It is known that the toner is conveyed to a developing area opposed to and develops toner by flying and adhering to the electrostatic latent image on the surface of the photosensitive drum in the developing area to develop the electrostatic latent image as a toner image. There is. In addition, LED and LBP printers have recently become the mainstream of the market as a printer device, and the direction of technology has become higher resolution, that is, 600, 800, 1200 dpi instead of 300, 400 dpi. Therefore, the developing system is also required to have higher definition. Further, the functions of copiers are also becoming more sophisticated, and as a result, they are moving toward digitalization. In this direction, the method of forming an electrostatic charge image with a laser is the main method, so it is also advancing toward high resolution, and here too, as with printers, high resolution and high definition development methods are required. JP-A-1-112253 and JP-A-2-284158 propose a toner having a small particle diameter, and the toner particle diameter is progressing toward a smaller particle diameter.

The toner image formed on the photoconductor in the developing process is transferred to the transfer material in the transfer process, but the transfer residual toner remaining on the photoconductor is cleaned in the cleaning process.
Toner is stored in the waste toner container. For this cleaning step, conventionally blade cleaning, fur brush cleaning, roller cleaning, etc. have been used. From the viewpoint of the apparatus, the size of the apparatus is inevitably increased due to the provision of such a cleaning apparatus, which has been a bottleneck when aiming to make the apparatus compact. Moreover,
From the viewpoint of ecology, a system with less waste toner is desired in the sense of effective utilization of toner, and a toner with good transfer efficiency has been demanded.

Japanese Patent Application Laid-Open No. 61-279864 proposes toners having shape factors SF-1 and SF-2. However, there is no description regarding transfer in this publication, and as a result of carrying out Examples, transfer efficiency is low and further improvement is required.

Further, Japanese Patent Application Laid-Open No. 63-235953 proposes a magnetic toner spherically shaped by a mechanical impact force. However, the transfer efficiency is still insufficient and further improvement is needed.

Further, in Japanese Patent Laid-Open No. 8-272133, shape factors SF-1, SF-2, and SF-2, which are excellent in transfer efficiency of a toner image, have a small amount of transfer residual toner, and can provide a high-quality image, A toner has been proposed which defines the relationship between the specific surface area per unit area of the toner and the specific surface area per unit area when the toner is assumed to be a true sphere.

However, the above-mentioned more spherical toner and the toner having a smooth surface as described above are apt to cause fusion on the sleeve, particularly in the concave portion of the sleeve surface. When fusion occurs on the sleeve, proper triboelectric charging is not applied to the toner, resulting in streaks on the image, unevenness, and reduction in image density.

On the other hand, as a regulation method for thinning the one-component developer on the developer carrier, for example, in the case of the magnetic one-component developer, the magnetic pole of the fixed magnet contained in the rotating developing sleeve, There is a method in which the amount of toner conveyed on the developer carrying member is regulated and thinned by the action of a magnetic field generated in a gap between the magnetic blade and a magnetic blade arranged at a position close to the sleeve and opposed to the magnetic pole. On the other hand, there is also a method in which a plate-shaped member or an elastic member is biased to the surface of the developing sleeve, and the contact pressure thereof makes the developer layer on the developer carrier thin. In particular, the latter is preferably used because the developer layer is thinner than the former. Further, it is also preferably used in a non-magnetic one-component developer containing no magnetic substance.

Conventionally, durability is considered important as a material used for the elastic blade. However, when the above-mentioned spherical or spheronized toner is used, the toner coating amount becomes higher than that of normal toner, so by setting the blade contact pressure higher, the toner coating on the sleeve The amount is adjusted so that toner adhesion and fusion are likely to occur on the blade surface. On the other hand, an elastic blade made of a silicone rubber material, a fluororubber material or the like is used in order to improve the releasability from the toner and prevent the toner fusion.

As the developer carrier used for the development, for example, a metal, an alloy thereof or a compound thereof is molded into a cylindrical shape, and the surface thereof is subjected to electrolysis, blasting, sanding, etc. to have a predetermined surface roughness. The processed one is used. However, in this case, the developer existing in the vicinity of the surface of the developer carrying member in the developer layer formed on the surface of the developer carrying member by the regulating member has a very high electric charge, so that the surface of the carrying member has a mirror image. Since the toner is strongly attracted, and thus the opportunity for friction between the toner and the carrier cannot be held, the developer cannot hold a suitable charge (so-called charge-up phenomenon). Under such a situation, sufficient development and transfer are not performed, resulting in an image with uneven image density and scattered characters. In order to prevent the generation of a developer having such an excessive electric charge and the firm adhesion of the developer, a film in which a conductive substance such as carbon / graphite or a solid lubricant is dispersed in a resin is used as the above-mentioned developer support. A method of forming on the body is proposed in Japanese Patent Laid-Open No. 1-277265. It is recognized that the above phenomenon is significantly reduced by using this method. However, in the above method, the shape of the sleeve surface is non-uniform, so that uniform charging is still insufficient, and there is a problem in durability such as brittleness of the coating layer.

Further, as disclosed in JP-A-3-200986, a conductive coating layer in which a conductive fine powder such as a solid lubricant and carbon and spherical particles are dispersed in a resin is provided on a metal substrate. A method of using such a sleeve in a developing device has been proposed. By using this method, the shape of the sleeve surface is made uniform, and charging is made uniform and abrasion resistance is improved. However, even in the above method, when the developing sleeve is used under severe durability conditions, the dispersibility of the spherical particles is still insufficient, so that abrasion of the conductive coating layer is likely to occur, and further, the abrasion causes the conductivity to decrease. If the spherical particles in the coating layer are exposed on the surface of the sleeve, toner contamination or fusion is likely to occur around the spherical particles as cores, and further improvement in durability is desired.

Further, as described above, when the convex portion having a certain height is not present on the sleeve surface, the toner fusion to the sleeve surface is likely to occur when the spheronized toner is used. On the other hand, it is necessary to reduce the load on the sleeve surface and suppress the occurrence of toner fusion by providing a convex portion having a certain height on the sleeve surface.

[0016]

That is, the object of the present invention is to solve the above-mentioned problems and to make the developer on the developer carrying member have a stable and suitable charge even in repeated image formation. It is an object of the present invention to provide a developing device developing method and an image forming method capable of obtaining a high-quality image which is uniform, has no streaks and unevenness, and does not cause image density reduction or ghost.

Further, the object of the present invention is to provide a toner having a small particle size and using a low temperature fixing material, and further a toner having a more spherical shape, for the purpose of high image quality and energy saving.
It is an object of the present invention to provide a developing method and a developing device capable of obtaining a high-definition and high-quality image by further improving the charging property or the developing property and preventing the sleeve fusion.

A further object of the present invention is to provide a developing method and a developing apparatus which can obtain a stable image without causing a defective image even in durability.

[0019]

The above object can be achieved by the present invention described below.

That is, according to the present invention, SF-1 is 100 to 1.
A magnetic one-component developer having a toner having a shape factor of 80, SF-2 of 100 to 140 is formed into a thin layer of the developer by a developer layer thickness regulating member that is in contact with the developer carrier, In the developing method, the developer layer formed by the agent carrying member is conveyed to a developing unit facing the latent image carrying member, and the latent image formed on the latent image carrying member is developed by the developer. The body has at least a substrate and a coating layer, the surface of the substrate is coated with the coating layer, the ten-point average roughness of the coating layer surface is Rz (μm), and the average particle size of the developer used is r ( μm), where S (%) is the ratio of the area occupied by the convex portions exceeding 1.5 × r (μm) from the reference plane of the surface of the coating layer, which is obtained by the least square method, the following condition 9 μm ≦ Rz ≦ 30 μm 1.25 ≦ Rz / r ≦ 6 0.015 % ≦ S ≦ 1. 914 %, and a developing device used in the developing method .

Further, the coating layer of the developer carrying material contains dispersed spherical particles having a volume average particle diameter of at least 3 to 30 μm, and the spherical particles are resin particles or conductive spherical particles. Characterize.

Further, conductive fine powder is dispersedly contained in the coating layer of the developer carrier to form a conductive coating layer,
The coating layer is characterized by containing a solid lubricant.

Further, the layer thickness regulating member is characterized by having an elastic body having a wear index of 0.03 to 0.15 which forms a nip with the developer carrying body, and silicone rubber is preferably used as the material thereof. .

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Ten-point average roughness (hereinafter referred to as Rz), which is the roughness on the surface of the coating layer of the developer carrier, average particle diameter of the developer used (hereinafter referred to as r), and roughness of the surface of the coating layer. The ratio (hereinafter S) of the area occupied by the convex portion exceeding 1.5 × r (μm) from the average line of the curve is the following condition 9 μm ≦ Rz ≦ 30 μm 1.25 ≦ Rz / r ≦ 6 0.015 % ≦ S ≦ It is desirable to satisfy 1.914 %, preferably the following condition 14 μm ≦ Rz ≦ 25 μm 2 ≦ Rz / r ≦ 6 0.015 % ≦ S ≦ 1.914 %. Rz is less than 9 μm, Rz /
If r is less than 1.25 and S is less than 0.01%, the load due to contact with the blade or toner increases, and toner fusion or toner contamination may occur. When Rz exceeds 30 μm or S exceeds 5%, it becomes difficult to uniformly coat the developing sleeve surface with the developer, which is not preferable.

Further, when the spherical one-component magnetic one-component developer is used, the center line average roughness (hereinafter, Ra) on the surface of the coating layer of the developer carrier is 0.5 μm ≦ Ra ≦ 2.5.
It is desirable to satisfy μm, preferably 0.7 μm
It is desirable to satisfy ≦ Ra ≦ 1.8 μm. If Ra is less than 0.5 μm, the toner fusion may be deteriorated and the developer transportability may be deteriorated, so that sufficient image density may not be obtained, and if it exceeds 2.5 μm, the developer transport amount may be large. It becomes too much and the toner cannot be sufficiently charged.

The film thickness of the coating layer is usually preferably 20 μm or less in order to obtain a uniform film thickness, but it is not particularly limited to this film thickness.

Next, the spherical particles used in the present invention will be described.

The spherical particles used in the present invention maintain a uniform surface roughness on the surface of the coating layer of the developer carrier and, at the same time, provide a certain amount of protrusions on the surface of the coating layer.
It is added in order to suppress the indirect pressing force by the regulating blade pressure on the surface of the coating layer and the load due to contact with the developer, and to prevent toner fusion and toner contamination from occurring.

The spherical particles preferably have a volume average particle diameter of 3 to 30 μm, preferably 5 to 25 μm, more preferably 10 to 25 μm, and a true density of 3 or less.

When the volume average particle diameter of the spherical particles is less than 3 μm, the effect of imparting uniform and sufficient roughness to the surface is poor, and toner charge-up due to abrasion of the coating layer, toner contamination and toner fusion occur, resulting in ghost. And deterioration of image density. If the volume average particle diameter exceeds 30 μm, the roughness of the surface of the coating layer becomes too large, which makes it difficult to sufficiently charge the toner and reduces the mechanical strength of the coating layer. "Spherical" in the present invention
Means that the ratio of major axis / minor axis of particles is 1.0 to 1.5 (preferably 1.0 to 1.2). Particularly, spherical particles are preferable.

Further, the spherical particles used in the present invention have a true density of 3 g / cm ³ or less, preferably 2.7 g / cm ³ or less. If the true density of the spherical particles exceeds ³ g / cm ³ , the dispersibility of the spherical particles in the coating layer will be insufficient, and it will be difficult to impart uniform roughness to the surface of the coating layer, resulting in uniform charging of the developer. And the strength of the coating layer becomes insufficient.

As the spherical particles used in the present invention, known spherical particles can be used. For example, there are spherical resin particles, spherical metal oxide particles, spherical carbonized particles, and the like, which are appropriately used according to the developing property of the developer and the developing system.

As the spherical resin particles, for example, spherical resin particles produced by suspension polymerization method, dispersion polymerization method or the like are used. With spherical resin particles, a suitable amount of surface roughness can be obtained with a smaller amount, and a more uniform surface shape can be easily obtained.
Examples of such spherical resin particles include acrylic resin particles such as polyacrylate and polymethacrylate, polyamide resin particles such as nylon, polyethylene resin, polyolefin resin particles such as polypropylene, silicone resin particles, phenol resin particles, Examples thereof include polyurethane resin particles, styrene resin particles, benzoguanamine particles, and the like. The resin particles obtained by the pulverization method may be thermally or physically spheroidized before use.

Further, the inorganic fine powder may be attached or fixed to the surface of the spherical resin particles. Such inorganic fine powders include SiO ₂ , SrTiO ₃ , C
eO ₂ , CrO, Al ₂ O ₃ , oxides such as ZnO and MgO, nitrides such as Si ₃ N ₄ , carbides such as SiC, C
Examples thereof include sulfates and carbonates such as aSO ₄ , BaSO ₄ , and CaCO ₃ .

Such inorganic fine powder may be treated with a coupling agent before use. In particular, it can be preferably used for the purpose of improving the adhesiveness with the binder resin or imparting hydrophobicity to the particles. Examples of such coupling agents include silane coupling agents, titanium coupling agents, zircoaluminate coupling agents, and the like. More specifically, for example, as a silane coupling agent, hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, Benzyldimethylchlorosilane, brommethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane,
Chlormethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethyldiethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyl Disiloxane, 1,3-diphenyltetramethyldisiloxane, and dimethylpolysiloxane having 2 to 12 siloxane units per molecule and each terminally located unit having a hydroxyl group bonded to a silicon atom. Etc.

By treating the surface of the spherical resin particles with the inorganic fine powder as described above, the dispersibility in the paint, the uniformity of the coating surface, the stain resistance of the coating, the charge imparting property to the developer, The abrasion resistance and the like of the coating layer can be improved.

Further, by making the spherical particles have conductivity, it is possible to prevent charges from accumulating on the surface of the particles due to the conductivity, and to reduce toner adhesion and improve the charge imparting property of the developer.

As a method for obtaining such conductive spherical particles, the following methods are preferable, but not limited to these methods. As a method for obtaining particularly preferred conductive spherical particles used in the present invention, resin-based spherical particles such as phenol resin, naphthalene resin, furan resin, xylene resin, divinylbenzene polymer, styrene-divinylbenzene copolymer and polyacrylonitrile are used. Spherical carbon particles having low density and good conductivity obtained by firing particles or mesocarbon microbeads to carbonize and / or graphitize, more preferably phenol resin, naphthalene resin, furan resin, xylene resin, divinyl. Bulk mesophase pitch is coated on the surface of spherical particles of benzene polymer, styrene-divinylbenzene copolymer, polyacrylonitrile, etc. by a mechanochemical method, which is heat treated in an oxidizing atmosphere and then fired to carbonize and / or graphite. It is a conductive spherical carbon particle obtained by liquefying. In any of the methods, the spherical carbon particles obtained by these methods can control the conductivity to some extent by changing the firing conditions and the like. In addition, the spherical carbon particles obtained by these methods may be plated with a conductive metal and / or a metal oxide, etc. to the extent that the true density does not exceed ³ g / cm ³ in order to further increase the conductivity in some cases. It may be given.

As another method for obtaining the conductive spherical particles preferably used in the present invention, conductive fine particles smaller than the particle diameter of the core particles are added to the surface of the core particles made of spherical resin particles at an appropriate mixing ratio. After mechanically mixing and applying conductive fine particles evenly around the resin particles by the action of Van der Waals force and electrostatic force, the surface of the resin particles is softened by the local temperature rise caused by mechanical impact force, for example. Conductive treated spherical resin particles formed by forming conductive fine particles into a film. As the constituent material of the mother particles, it is preferable to use a resin which is a spherical organic compound having a small core density, and for example, PMMA, an acrylic resin, a polybutadiene resin, a polystyrene resin, polyethylene, polypropylene, polybutadiene, or a combination thereof. Resin particles of a polymer, benzoguanamine resin, phenol resin, polyamide resin, nylon, fluorine resin, silicone resin, epoxy resin, polyester resin or the like can be used. Further, as the conductive fine particles that are small particles,
In order to uniformly coat the conductive fine particles, the particle size of the small particles is preferably 1/8 or less of the particle size of the mother particles.

As another method for obtaining the conductive spherical particles preferably used in the present invention, the conductive fine particles are uniformly dispersed in the spherical resin particles. After the fine particles are dispersed and kneaded, the fine particles are pulverized to a predetermined particle size, and the polymerization initiator, the conductive fine particles, and other additives are added to the conductive spherical particles and the polymerizable monomer that are spheroidized by mechanical treatment and thermal treatment. An agent is added, and the monomer composition uniformly dispersed by a disperser or the like is suspended in an aqueous phase containing a dispersion stabilizer by a stirrer or the like so as to have a predetermined particle diameter, and polymerization is performed to obtain Other examples include spherical particles having conductive fine particles dispersed therein. The conductive fine particle-dispersed spherical particles obtained by these methods are mechanically mixed with the conductive fine particles having a particle size smaller than the above core particles in an appropriate mixing ratio, and the conductive particles are electrically conductive by the action of van der Waals force and electrostatic force. After the conductive fine particles are uniformly attached to the periphery of the conductive fine particle-dispersed spherical particles, the conductive fine particle-dispersed resin particle surface is softened by a local temperature rise caused by, for example, mechanical impact force, and the conductive fine particles are formed into a film. Further, the conductivity may be increased for use.

The amount of spherical particles added to the coating layer used in the present invention is 2 to 12 relative to 100 parts by weight of the binder resin.
A range of 0 parts by weight gives particularly favorable results. If it is less than 2 parts by weight, the effect of adding spherical particles is small, and if it exceeds 120 parts by weight, the chargeability of the toner may be too low.

As the binder resin material for the coating layer, generally known resins can be used. For example, styrene resin,
Thermoplastic resin such as vinyl resin, polyether sulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, fluororesin, fiber resin, acrylic resin, epoxy resin, polyester resin, alkyd resin, phenol resin, melamine resin A heat- or photo-curable resin such as polyurethane resin, urea resin, silicone resin, or polyimide resin can be used. Above all, it has excellent releasability such as silicone resin and fluororesin, or excellent mechanical properties such as polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane, styrene resin, and acrylic resin. More preferred are:

The volume resistance of the coating layer of the developer carrying member of the present invention is preferably 10 ³ Ω · cm or less. When the volume resistance of the coating layer exceeds 10 ³ Ω · cm, charge-up of the developer is likely to occur, which causes deterioration of ghost and reduction of density.

As the constitution of the conductive coating layer of the developer carrying member of the present invention, the effect of the present invention is further promoted by dispersing the lubricating substance in the coating resin layer together with the spherical conductive particles. It is preferable because Examples of the lubricating substance include graphite, molybdenum disulfide, boron nitride, mica, graphite fluoride, silver-niobium selenide, calcium chloride-graphite, talc, and fatty acid metal salts such as zinc stearate. Is preferably used because it does not impair the conductivity of the coating layer. It is preferable to use those lubricants having a number average particle diameter of preferably about 0.2 to 20 μm, more preferably 1 to 15 μm.

The addition amount of the above-mentioned lubricating substance gives a particularly preferable result in the range of 10 to 120 parts by weight with respect to 100 parts by weight of the binder resin. When it exceeds 120 parts by weight, a decrease in coating strength and a decrease in the charge amount of the developer are observed,
If the amount is less than 10 parts by weight, the toner may be easily contaminated on the surface of the coating layer, for example, when the toner is used for a long time with a toner having a small particle diameter of 7 μm or less.

In the developer carrier of the present invention, in order to adjust the volume resistance of the coating layer, other conductive fine particles may be dispersed and contained in the binder resin. As such conductive fine particles,
The number average particle diameter is preferably 1 μm or less.

The conductive fine particles used in the present invention include carbon black such as furnace black, lamp black, thermal black, acetylene black and channel black; titanium oxide, tin oxide, zinc oxide, molybdenum oxide, titanic acid. Metal oxides such as potassium, antimony oxide and indium oxide; aluminum,
Metals such as copper, silver and nickel, graphite, metal fibers,
Examples include inorganic fillers such as carbon fibers.

Next, the structure of the developer carrying member used in the present invention will be described.

The developer carrying member comprises a substrate and a resin layer surrounding and covering the substrate. The substrate may be a cylindrical member, a cylindrical member, a belt-shaped member, or the like, but a metal cylindrical tube is preferably used. As the metal cylindrical tube, stainless steel, aluminum or the like is preferably used.

The addition amount of the conductive fine particles of 1 μm or less in the above-mentioned coating layer is 40 parts by weight or less with respect to 100 parts by weight of the binder resin, and particularly preferable results are obtained. Four
If it exceeds 0 part by weight, the film strength and the toner charge amount are decreased.

Next, the layer thickness regulating member used in the present invention will be described.

The layer thickness regulating member used in the present invention has a wear index for forming a nip with the developer carrier of 0.03 to 0.
15 and the contact pressure P (g / cm) of the elastic body is 10 ≦ P
It is desirable that ≦ 60. If the wear index is small, streaks due to aggregates are likely to occur, and if it is too large, the layer thickness regulating member is likely to be unevenly scraped. If P is smaller than 10, the toner is insufficiently charged, and if it is larger than 60, the toner coating amount is small and the lines are scattered due to durability.

As the material of the layer thickness regulating member, a rubber elastic body such as silicone rubber, urethane rubber or NBR; a synthetic resin elastic body such as polyethylene terephthalate; a metal elastic body such as stainless steel or steel can be used. Moreover, even those composites can be used. A rubber elastic body is preferable, and silicone rubber is particularly preferable in terms of abrasion resistance.
Further, it is preferable that the silicone rubber has a rubber hardness of 10 or more and 55 or less according to JIS and contains 5 to 20 parts by weight of silica as a filler. If the rubber hardness is large, the wear index is small, and the nip and the wear amount are small, so that streaks due to aggregates are likely to occur, and if it is too small, the wear index becomes large and the layer thickness regulating member is liable to be unevenly scraped. Further, if the amount of the filler in the rubber is large, unevenness in blade abrasion or chipping causes uneven coating of the toner, which easily causes streaks.

The methods for measuring physical properties relating to the present invention will be described below.

(1) Center line average roughness (R
Measurement of a) Using a surf coder SE-3400 manufactured by Kosaka Laboratory, a feed speed of 0.5 mm / sec and a measurement length of 8.0.
mm, roughness cutoff λc = 0.8, and automatic leveling-on conditions were measured at 5 points in the axial direction × 4 points in the circumferential direction = 20 points, and the average value was taken.

(2) Ten-point average roughness (R
Under the same conditions as the measurement center line average roughness (Ra) of z), 5 points in the axial direction × 4 points in the circumferential direction = 20 points were measured using a surf coder SE-3400 manufactured by Kosaka Laboratory, and the average value was taken. It was

(3) Measurement of the ratio (S) of the area occupied by the convex portions on the surface of the coating layer Using a surf coder SE-3400 manufactured by Kosaka Laboratory and a 3D controller AK-1, a feed speed of 0.5 mm
/ Sec, axial measurement length 2.0 mm, circumferential measurement length 0.1 mm, circumferential feed pitch 0.001 mm, number of scans 100, roughness cutoff λc = 0.8. . As a measuring method, every time the stylus scans one line in the X-axis direction (the axial direction of the developer carrying member), to the next Y coordinate (the circumferential direction of the developer carrying member) at a constant feed pitch. By moving and continuing the scan a set number of times, three-dimensional unevenness distribution data in a 2.0 mm × 0.1 mm measurement region is obtained. The measurement result was analyzed by an IBM personal computer, and the occupation area ratio S at the height of toner particle size r × 1.5 (μm) was calculated from the reference surface obtained by the least square method. Here occupied area ratio S is, S ₁ and the area of the cut of height convex part cut by the reference surface and a plane parallel with the toner particles having a particle diameter from the reference plane r × 1.5 (μm), the reference of the measurement region If the surface area is S ₂ , then S = S ₁ / S ₂ × 100
It is represented by (%).

(4) Particle size measurement of spherical particles The particle size was measured using a Coulter LS-130 type particle size distribution meter (manufactured by Coulter Co.) of a laser diffraction type particle size distribution meter, and the volume average diameter calculated from the volume distribution was determined. Isopropyl alcohol was used as the solvent for the measurement, and the measurement sample was 2 to 20.
mg was added to 100 to 150 ml of the solvent, and the dispersion treatment was performed for about 1 to 3 minutes with an ultrasonic disperser, and the dispersion was measured with the above apparatus. The refractive index was 1.375, and the optical model had a real part 1.5 and an imaginary part 0.3.

(5) Measurement of particle size of magnetic one-component developer: Measurement was carried out by attaching a 100 μm aperture to a Multisizer II type manufactured by Coulter Co., Ltd., and the weight-based weight average diameter obtained from the volume distribution was determined. As a measuring method, a 1% NaCl aqueous solution was prepared using primary sodium chloride, and a surfactant (preferably alkylbenzene sulfonate) as a dispersant was added to 100 to 150 ml of this aqueous solution in an amount of 0.1%.
Add 1 to 5 ml, add 2 to 20 mg of the measurement sample,
Dispersion treatment was performed for about 1 to 3 minutes with an ultrasonic disperser, and the measurement was performed with the above-mentioned device.

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

In FIG. 1, an image bearing member that bears an electrostatic latent image formed by a known process, for example, the electrophotographic photosensitive drum 1 is rotated in the unmarked B direction. The sleeve 8 of the developing roller 12 carries the magnetic one-component developer 4 as the one-component developer supplied by the hopper 3 and rotates in the direction of arrow A, whereby the developing sleeve 8 and the photosensitive drum 1 are separated from each other. The magnetic one-component developer 4 is conveyed to the developing unit D facing the magnetic developer. Inside the developing sleeve 8, a magnet 5 is arranged to magnetically attract and hold the magnetic one-component developer 4 on the developing sleeve 8. The developing sleeve 8 has a conductive resin layer 7 coated on the metal cylindrical tube 6.
A stirring blade 10 for stirring the magnetic one-component developer 4 is provided in the hopper 3.

Silicone rubber having rubber elasticity is preferably used as a member for regulating the layer thickness of the magnetic one-component developer 4 on the developing sleeve 8. In the developing device shown in FIG. 1, the elastic plate 11 is pressed against the developing sleeve 8 in the direction opposite to the rotational direction. In the developing device shown in FIG. 2, the elastic plate 11 is oriented in the forward direction with respect to the rotational direction of the developing sleeve 8. It is pressed. In such a developing device, a thin toner layer can be formed on the developing sleeve 8. Magnetic one-component developer 4
The thickness of the thin layer is preferably thinner than the minimum gap between the developing sleeve 8 and the photosensitive drum 1 in the developing section D. The magnetic one-component developer 4 is the developing sleeve 8
By friction with the conductive resin layer 7 and the elastic plate 11 above, a triboelectric charge capable of developing the electrostatic latent image on the photosensitive drum 1 is obtained. The present invention is effective for a developing device that develops an electrostatic latent image with such a thin toner layer, that is, a non-contact developing device.

A developing bias voltage is applied to the developing sleeve 8 from a power source 9 in order to fly the magnetic one-component developer 4 which is the one-component magnetic developer carried on the developing sleeve 8. When a DC voltage is used as the developing bias voltage, a voltage having a value between the potential of the image portion (the area where the magnetic one-component developer 4 is attached and visualized) of the electrostatic latent image and the potential of the background portion. Is preferably applied to the developing sleeve 8. On the other hand, 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 8 to form an oscillating electric field in which the direction is alternately inverted in the developing portion D.

In this case, it is preferable to apply to the developing sleeve 8 an alternating bias voltage in which a DC voltage component having a value between the potential of the image portion and the potential of the background portion is superimposed.

Further, in so-called regular development in which a magnetic one-component developer is attached to the high potential portion of the electrostatic latent image having a high potential portion and a low potential portion to visualize the electrostatic latent image, the polarity is opposite to that of the electrostatic latent image. In the so-called reversal development, in which the magnetic one-component developer is applied to the low-potential portion of the electrostatic latent image to make it visible, the magnetic one-component developer has the polarity of the electrostatic latent image. A magnetic one-component developer that is charged to the same polarity is used. In addition, high potential,
The low potential is expressed by an absolute value. In any case, the magnetic one-component developer 4 is charged by friction with the developing sleeve 8.

FIGS. 1 and 2 are merely schematic examples, and it goes without saying that there are various forms such as the shape of the container, the presence / absence of a stirring member, and the arrangement of magnetic poles.

Next, the magnetic one-component developer will be described.

The toner contained in the magnetic one-component developer is mainly obtained by melting and kneading a resin, a release agent, a charge control agent, a colorant and the like,
It is a fine powder with a uniform particle size distribution after solidification, pulverization, and subsequent classification.

As the binder resin used in the toner, generally known resins can be used. For example, styrene,
Monomers of styrene such as α-methylstyrene and p-chlorostyrene and their substitution products; 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, styrene -Dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer,
Styrene-based copolymers such as styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer; polymethyl methacrylate , Polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin,
Tempel resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, paraffin wax, carnauba wax and the like can be used alone or in combination.

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

In order to use the toner as a magnetic toner,
Magnetic powder may be contained in the toner. As such magnetic powder, a substance that is magnetized in a magnetic field is used, and examples thereof include powders of ferromagnetic metals such as iron, cobalt and nickel, and alloys and compounds such as magnetite, hematite and ferrite. The content of the magnetic powder is preferably 15 to 70% by weight based on the weight of the toner. The toner may contain waxes for the purpose of improving releasability during fixing and fixing property. Examples of such waxes include paraffin wax and its derivatives, microcrystalline wax and its derivatives, Fischer-Tropsch wax and its derivatives, polyolefin wax and its derivatives, carnauba wax and its derivatives, etc. Includes block copolymers and graft modified products with vinyl monomers. In addition, alcohols, fatty acids, acid amides, esters, ketones, hydrogenated castor oil and its derivatives, plant waxes, animal waxes, mineral waxes, petrolactam and the like can be used.

If necessary, the toner may contain a charge control agent. The charge control agents include negative charge control agents and positive charge control agents. For example, the following substances are used to control the toner to be negatively charged. For example, organic metal complexes and chelate compounds are effective, and there are monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid metal complexes. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol. Further, there are the following substances for positively charging the toner. Modified products of nigrosine and fatty acid metal salts, quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and onium such as phosphonium salts which are analogs thereof. Salts and lake pigments thereof (as a laking agent, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.), metal salts of higher fatty acids ;
Dibutyltin oxide, dioctyltin oxide,
Diorganotin oxide such as dicyclohexyltin oxide; diorganotinborates such as dibutyltin borate, dioctyltin borate, and dicyclohexyltin borate; guanidine compounds and imidazole compounds.

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

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

Alternatively, untreated fine powder treated with a nitrogen-containing silane coupling agent may be used. It is particularly preferable in the case of a positive magnetic one-component developer. 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,
Examples include trimethoxysilyl-γ-propylimidazole and the like.

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

As another organic treatment, it is also possible to use fine powder treated with silicone oil. The silicone oil is generally represented by the following formula (1).

[0078]

[Chemical 1] [In the formula, R represents an alkyl group (for example, a methyl group) or an aryl group, and n represents an integer. ]

The preferred silicone oil is 25
The viscosity at 0 ° C is approximately 0.5 to 10,000 mm ² /
s, preferably 1 to 1000 mm ² / s, such as methylhydrogen silicone oil, dimethyl silicone oil, phenylmethyl silicone oil, chlorophenylmethyl silicone oil, alkyl-modified silicone oil, fatty acid-modified silicone oil, polyoxy Examples thereof include alkylene-modified silicone oil and fluorine-modified silicone oil. Moreover, you may use the silicone oil which has a nitrogen atom in a side chain.
Particularly, it is preferable in the case of a positive magnetic one-component developer.

The treatment with silicone oil can be carried out, for example, as follows. The pigment is vigorously stirred while being heated if necessary, and the silicone oil or the solution thereof is sprayed or vaporized and sprayed on the pigment, or the pigment is made into a slurry, and the silicone oil or the silicone oil is stirred while stirring the pigment. It can be easily processed by dropping the solution.

These silicone oils may be used alone or as a mixture of two or more, or may be used in combination or subjected to multiple treatment. Further, the treatment with a silane coupling agent may be used together.

The toner used in the present invention is preferably subjected to a spheroidizing treatment and a surface smoothing treatment by various methods, because the transferability becomes good, which is preferable. One such method is
A device having a stirrer blade or blade, and a liner or casing, for example, when the toner is passed through a minute gap between the blade and the liner, the surface is smoothed or the toner is made spherical by mechanical force. There are a method, a method of suspending the toner in warm water to make it spherical, a method of exposing the toner to a hot air stream to make it spherical. Further, as a method for producing a spherical toner, a mixture containing a monomer as a toner binder resin as a main component is suspended in water,
There is a method of polymerizing it into a toner. As a general method, a polymerizable monomer, a coloring agent, a polymerization initiator, and if necessary, a crosslinking agent, a charge control agent, a release agent, and other additives are uniformly dissolved or dispersed to form a single amount. After the body composition,
This monomer composition is a continuous layer containing a dispersion stabilizer, for example, dispersed in an aqueous phase using a suitable stirrer, and at the same time a polymerization reaction is carried out to obtain a developer having a desired particle size. is there.

These toners having good transferability have a shape factor of SF-1 and SF-2 of 100≤SF-1≤18.
0, 100 ≦ SF−2 ≦ 140.

SF-1 and SF-2 indicating the shape factor are
For example, using a FE-SEM (S-800) manufactured by Hitachi, Ltd., a toner image with a size of 2 μm or more magnified 1000 times is 10
0 pieces are randomly sampled, and the image information is sampled through an interface, for example, an image analysis device (L
uzexIII) and analyze it, and the values calculated by the following equation are defined as shape factors SF-1 and SF-2.

[0085]

[Equation 1] (In the formula, MXLNG is the absolute maximum length of the particle, PERIME
Is the perimeter of the particle, and AREA is the projected area of the particle. )

The shape factor SF-1 indicates the degree of roundness of the toner particles, and the shape factor SF-2 indicates the degree of unevenness of the toner particles.

[0087]

EXAMPLES The present invention will now be described in detail with reference to examples, but the examples do not limit the present invention.
All percentages and parts in the examples are parts by weight.

Example 1 As the spherical particles, spherical PMMA particles A-1 having a volume average particle diameter of 13.4 μm were used. A
The physical properties of -1 are shown in Table 1.・ Resol type phenolic resin solution (containing 50% methanol) 200 parts ・ 45 parts graphite having a number average particle size of 6.1 μm ・ 5 parts conductive carbon black ・ 130 parts isopropyl alcohol

Zirconia beads having a diameter of 1 mm were added to the above material as media particles, dispersed in a sand mill for 2 hours, and the beads were separated using a sieve to obtain a stock solution B-1.

Next, 5 parts of conductive spherical carbon particles A-1 were added to 380 parts of the stock solution of B-1, and isopropyl alcohol was added so that the solid content concentration became 32%, and then the diameter was 3 m.
m glass beads were dispersed for 1 hour, and the beads were separated using a sieve to obtain a coating liquid.

Using this coating solution, a coating layer was formed on an aluminum cylindrical tube having an outer diameter of 16 mmφ by a spray method, followed by heating in a hot air drying oven at 150 ° C. for 30 minutes to cure the developer carrying member C- 1 was produced. The adhesion weight of the coating layer after drying was 100 mg. Table 2 shows the physical properties of the coating layer of the developer carrying member.

The following were used as the magnetic one-component developer. -Styrene-butyl acrylate-butyl maleate half ester copolymer 100 parts-Magnetite 92 parts-Negative charge control agent 2 parts-Low molecular weight polyethylene 6 parts

The above materials were premixed using a Henschel mixer, and then melt-kneaded using a twin-screw extruder set at 130 ° C. After cooling the kneaded product, coarse pulverization was performed using a speed mill, and further fine pulverization was performed using a jet mill. The finely pulverized product was removed of fine powder and coarse powder using an elbow jet classifier. Further, the classified product was passed through the treated product having a minute gap between the casing and the blade with the atmosphere temperature set at 70 ° C. to modify the surface of the classified product particles to obtain a toner. The obtained toner had an SF-1 of 145 and an SF-2 of 122. To 100 parts of this toner, 1.0 of hydrophobic colloidal silica treated with a silane coupling agent and silicone oil
Parts were externally added and mixed with a Henschel mixer to obtain a magnetic one-component developer E-1.

The weight average particle diameter of the magnetic one-component developer E-1 was 7.5 μm. The particle size distribution was measured by attaching a 100 μm aperture to a Multisizer II type manufactured by Coulter, Inc.

Using this magnetic one-component developer and the sleeve, image formation was evaluated using LBP-930 (manufactured by Canon Inc.). The sleeve was processed and attached to an EP-W cartridge for laser jet VSi so that it could be attached. Further, 900 g of the toner was filled. As the elastic regulation blade, a silicone rubber in which colloidal silica was dispersed in silicone rubber was cut like a blade and attached to a washer. Using this cartridge, about 20 in N / N durable environment (23 ° C / 60% RH) and H / H durable environment (32.5 ° C / 85% RH) until the toner runs out.
Durability images of 000 sheets were printed. Table 3 shows the evaluation results at this time.

[Evaluation] (1) Image Density The image density was measured with a reflection densitometer RD918 (manufactured by Macbeth Co.).

(2) An image in which a ghost solid white area and a solid black area are adjacent to each other is developed at the image leading edge portion (the first rotation of the sleeve rotation), and the density of solid white marks and solid black marks appearing on the halftone after the second cycle. The difference was mainly compared visually to refer to the image density measurement. The evaluation results are shown by the following indexes. (N in the table is a ghost in which the solid black traces appear to have a lower density than the solid white traces. The opposite is true for those without N display.) ⊚: No difference in shade is seen. ○: A slight difference in shade can be confirmed depending on the viewing angle. B: The difference in density can be visually confirmed, but the difference in image density is within 0.01. Δ ○: A difference in gray level to the extent that the edge is not clear can be confirmed, but is practically OK level. Δ: The difference in lightness and darkness is slightly clear, and is the lower limit of the practical level. Δx: The difference in light and shade can be clearly confirmed, and can be confirmed as the difference in image density. Inferior to practical level. X: The difference in density is considerably large, and the difference in density by the reflection densitometer is 0.05 or more.

(3) Fog Density The reflectance of solid white areas was measured, and the reflectance of unused paper was measured and subtracted from the previous value to obtain the fog density. The reflectance was measured by TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.). ◎: 1.5 or less; almost unknown ○: 1.5 to 2.5; not understood unless carefully observed: Δ: 2.5 to 3.5; fogging gradually becomes recognizable ×: 3.5 to 4 .0: Fog can be seen at a glance at the lower limit of practical level x: 4.0 to 5.0;

(4) The magnetic one-component developer on the surface of the sleeve was removed by a vacuum cleaner and an air blow (by an air gun) after the sleeve was contaminated, and observed with an electron microscope (FE-SEM) for reference. Indicated by. ⊚: There is no developer toner. A: Fine toner powder of the developer is slightly observed in the depressions on the sleeve surface. ○ △, △ ○: The toner of the developer remains in the recesses on the sleeve, but the original shape of the toner particles remains. (○
△ is better. ) Δ: The toner of the developer adhering to the sleeve is present in some places, and the toner particles are crushed as if they were slightly melted. Δx: The toner sticking of the developer is seen on about 20% of the sleeve surface. Intermediate level between △ and × △. X: The toner of the developer can be visually confirmed. There is no streak-like fusion, but when viewed by SEM, melted and smoothed toner is present in a considerable part on the sleeve. X: The melted and smoothed toner adheres to a considerable portion on the sleeve. In addition, streak-like fusion is partially visible all around the sleeve.

Example 2 As the spherical particles, spherical PMMA particles A-2 having a volume average particle diameter of 22.1 μm were used. A
The physical properties of -2 are shown in Table 1. Next, B manufactured in Example 1
A developer carrying member C-2 was prepared in the same manner as in Example 1 except that 5 parts of A-2 was added as spherical particles to 380 parts of the stock solution of -1 instead of A-1. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

Example 3 As the spherical particles, spherical PMMA particles A-3 having a volume average particle diameter of 8.4 μm were used. A-
The physical properties of No. 3 are shown in Table 1. Next, B- produced in Example 1
As a spherical particle in 380 parts of the stock solution of No. 1 instead of A-1
A developer carrying member C-3 was produced in the same manner as in Example 1 except that 5 parts of -3 was added. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

Example 4 The same as Example 1 except that 10 parts of A-1 was added to 380 parts of the stock solution of B-1 produced in Example 1 instead of 5 parts of A-1 as spherical particles. Then, a developer carrying member C-4 was produced. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

Example 5 Same as Example 1 except that 1 part of A-1 was added to 380 parts of the stock solution of B-1 produced in Example 1 as spherical particles, instead of adding 5 parts of A-1. Then, a developer carrying member C-5 was produced. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

<Example 6> In the same manner as in Experiment 1, SF
A magnetic one-component developer E-2 having a weight average particle diameter of 5.1 μm and having a toner in which −1 was 147 and SF-2 was 132 was prepared. This magnetic one-component developer E-2 and sleeve C-
Using No. 1 as in Example 1, a durability evaluation test of the developer carrying member was performed while supplying the magnetic one-component developer.

Example 7 As a magnetic one-component developer, E was used.
A durability evaluation test was performed on the developer bearing member in the same manner as in Example 2 except that E-2 was used instead of -1.

<Embodiment 8> E as a magnetic one-component developer
A durability evaluation test of the developer carrying member was performed in the same manner as in Example 3 except that E-2 was used instead of -1.

<Example 9> In the same manner as in Experiment 1, SF
-1 is 143 and SF-2 is 129, and the magnetic one-component developer E-3 having a weight average particle diameter of 13.2 μm is used.
Was produced. This magnetic one-component developer E-3 and sleeve C
Using -1, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

Example 10 A durability evaluation test of a developer bearing member was carried out in the same manner as in Example 2 except that E-3 was used instead of E-1 as the magnetic one-component developer.

Example 11 As spherical particles, 11.7
100 parts of spherical phenolic resin of μm was uniformly coated with 14 parts of coal-based bulk mesophase pitch powder of 3 μm or less by using a Reiki machine (automatic mortar, manufactured by Ishikawa Industry Co., Ltd.), and then heat stabilization treatment was performed in an oxidizing atmosphere. After 2600 ℃
Spherical conductive carbon particles A-4 obtained by graphitizing by firing at were used. Table 1 shows the physical properties of A-4.

Next, the stock solution 3 of B-1 produced in Example 1
A developer carrying member C-6 was produced in the same manner as in Example 1 except that 10 parts of A-4 as a conductive spherical particle was added to 80 parts. The adhesion weight of the coating layer after drying was 100 mg. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

Example 12 As spherical particles, the following materials were used, kneading, pulverizing and classifying to obtain conductive particles having a number average particle size of 10.4 μm, and then hybridizer (manufactured by Nara Machinery Co., Ltd.). Conductive spherical resin particles A-5 obtained by carrying out the spheroidizing treatment with were used. A-
The physical properties of No. 5 are shown in Table 1.・ Styrene-acrylic resin 100 parts ・ Conductive carbon black 25 parts

Next, the stock solution 3 of B-1 produced in Example 1
A developer carrying member C-7 was produced in the same manner as in Example 1 except that 10 parts of A-5 as a conductive spherical particle was added to 80 parts. The adhesion weight of the coating layer after drying was 103 mg. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

<Example 13> As spherical conductive particles, 100 parts of the particles of A-4 used in Example 11 were added to 100 parts of copper and silver.
The metal-coated carbon particles A-6 whose parts were plated were used. A-
The physical properties of No. 6 are shown in Table 1.

Next, the stock solution 3 of B-1 produced in Example 1
A developer carrying member C-8 was produced in the same manner as in Example 1 except that 10 parts of A-6 as a conductive spherical particle was added to 80 parts. The adhesion weight of the coating layer after drying was 106 mg. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

<Example 14> Evaluation was made in the same manner as in Example 1 except that the elastic regulating blade in Example 1 was changed from silicone rubber to urethane.

Comparative Example 1 A developer carrying member D-1 was prepared in the same manner as in Example 1 except that the spherical particles A-1 used in Example 1 were excluded. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

Comparative Example 2 5 parts of spherical PMMA particles A-7 having a volume average particle size of 31.2 μm were added to 380 parts of the stock solution of B-1 produced in Example 1 instead of the spherical particles A-1. A developer carrying member D-2 was produced in the same manner as in Example 1 except for the above. The adhesion weight of the coating layer after drying was 98 mg. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

Comparative Example 3 Same as Example 1 except that 20 parts of A-1 was added to 380 parts of the stock solution of B-1 produced in Example 1 instead of 5 parts of A-1 as spherical particles. Then, a developer carrying member D-3 was prepared. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

<Comparative Example 4> In the same manner as in Experiment 1, SF
A magnetic one-component developer E-4 having a weight average particle diameter of 4.5 μm and having a toner in which −1 was 142 and SF-2 was 133 was prepared. This magnetic one-component developer E-4 and sleeve C-
2 was used to supply a magnetic one-component developer in the same manner as in Example 1, and a durability evaluation test was conducted on the developer carrying member.

<Comparative Example 5> E as a magnetic one-component developer
B-3 produced in Example 1 using E-3 in place of -1
A developer carrying member D-4 was prepared in the same manner as in Example 1 except that 3 parts of A-3 as spherical particles was added to 380 parts of the stock solution of No. 1. Table 2 shows the physical properties of the coating layer of the developer carrying member.
Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

Comparative Example 6 Developer carrying member D-5 was prepared in the same manner as in Example 1 except that 1 part of A-3 as spherical particles was added to 380 parts of the stock solution of B-1 produced in Example 1. Was produced. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

Comparative Example 7 Conductive non-spherical resin particles A obtained by kneading, pulverizing and classifying the following materials.
-8 was used. Table 1 shows the physical properties of A-8.・ Styrene-acrylic resin 100 parts ・ Conductive carbon black 25 parts

Next, the stock solution 3 of B-1 produced in Example 1
A developer carrying member D-6 was produced in the same manner as in Example 1 except that 10 parts of A-8 as a conductive spherical particle was added to 80 parts. The adhesion weight of the coating layer after drying was 103 mg. Table 2 shows the physical properties of the coating layer of the developer carrying member. Subsequently, while supplying the magnetic one-component developer in the same manner as in Example 1, a durability evaluation test of the developer carrying member was performed.

[0124]

[Table 1]

[0125]

[Table 2]

[0126]

[Table 3]

[0127]

As described above, according to the present invention,
The developer can stably have a triboelectric charge even in repeated image formation, and a high-quality image can be obtained without a decrease in image density or generation of ghost. Further, even in the case of a toner having a small particle diameter and a more spherical shape, by improving the charging property or the developing property and preventing the toner fusion and the like,
It is possible to obtain a high-definition and high-quality image without streaks and unevenness.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a developing device according to the present invention.

FIG. 2 is a sectional view showing another example of the developing device according to the present invention.

[Explanation of symbols] 1 Electrophotographic photosensitive drum (latent image carrier) 3 hopper (developer container) 4 Magnetic one-component developer 5 magnets 6 Metal Cylindrical Tube 7 coating layer 8 Development sleeve (developer carrier) 9 power supplies 10 stirring blades 11 Elasticity regulation blade 12 Development roller A Development sleeve rotation direction B Photosensitive drum rotation direction D development section

Front Page Continuation (72) Inventor Kenji Fujishima 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kazuki Saiki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Naoki Okamoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) Reference JP-A-8-179617 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 15/08 501 G03G 15/08 504 G03G 9/08 372 G03G 9/083 G03G 15/09 101

Claims (27)

(57) [Claims] 1. SF-1 is 100 to 180, SF-2
A magnetic one-component developer having a toner having a shape factor of 100 to 140 is formed by a developer layer thickness regulating member that is in contact with the developer carrier to form a thin layer of the developer. In the developing method, in which the formed developer layer is conveyed to a developing unit facing the latent image carrier, and the latent image formed on the latent image carrier is developed with the developer, the developer carrier is at least a substrate and Has a coating layer,
The surface of the substrate is coated with a coating layer, the ten-point average roughness of the surface of the coating layer is Rz (μm), the average particle size of the developer used is r (μm), and the least squares method of the surface of the coating layer is used. when the proportion of the area occupied by the convex portion exceeding the reference plane from 1.5 × r (μm) obtained was S (%) by the following conditions 9μm ≦ Rz ≦ 30μm 1.25 ≦ Rz / r ≦ 6 0 A developing method characterized by satisfying 0.15 % ≦ S ≦ 1.914 %. 2. The coating layer of the developer carrying member is formed of a coating film in which spherical particles having a volume average particle diameter of 3 to 30 μm are dispersed and contained in a binder resin. The developing method described. 3. The developing method according to claim 2, wherein the spherical particles in the coating layer of the developer carrier are resin particles. 4. The developing method according to claim 2, wherein the spherical particles in the coating layer of the developer carrier are electrically conductive spherical particles. 5. The developing method according to claim 1, wherein a conductive fine powder is further dispersed and contained in the coating layer of the developer carrying member to form a conductive coating layer. 6. The developing method according to claim 1, wherein a solid lubricant is contained in the coating layer of the developer carrying member. 7. The developing method according to claim 1, wherein the layer thickness regulating member has elasticity. 8. The developing method according to claim 7, wherein the layer thickness regulating member has an elastic body having a wear index of 0.03 to 0.15 which forms a nip with the developer carrying member. 9. The developing method according to claim 7, wherein the layer thickness regulating member is a silicone rubber. 10. SF-1 is 100 to 180, SF-
A magnetic one-component developer having a toner 2 having a shape factor of 100 to 140 is formed while a thin layer of the developer is formed by a developer layer thickness regulating member that is in contact with the developer carrier. In a developing device that conveys the developer layer formed by the above to a developing section facing the latent image carrier, and develops the latent image formed on the latent image carrier, the developer carrier is at least a substrate and Has a coating layer,
The surface of the substrate is coated with a coating layer, the ten-point average roughness of the surface of the coating layer is Rz (μm), the average particle size of the developer used is r (μm), and the least squares method of the surface of the coating layer is used. when the proportion of the area occupied by the convex portion exceeding the reference plane from 1.5 × r (μm) obtained was S (%) by the following conditions 9μm ≦ Rz ≦ 30μm 1.25 ≦ Rz / r ≦ 6 0 A developing device characterized by satisfying 0.15 % ≦ S ≦ 1.914 %. 11. The coating layer of the developer carrying member,
11. The developing device according to claim 10, comprising a coating film in which spherical particles having a volume average particle diameter of 3 to 30 μm are dispersed and contained in a binder resin. 12. The developing device according to claim 11, wherein the spherical particles in the coating layer of the developer carrier are resin particles. 13. The developing device according to claim 11, wherein the spherical particles in the coating layer of the developer carrier are electrically conductive spherical particles. 14. The developing device according to claim 10, wherein a conductive fine powder is further dispersed and contained in the coating layer of the developer carrying member to form a conductive coating layer. 15. The developing device according to claim 10, wherein a solid lubricant is contained in the coating layer of the developer carrying member. 16. The developing device according to claim 10, wherein the layer thickness regulating member has elasticity. 17. The developing device according to claim 16, wherein the layer thickness regulating member includes an elastic body having a wear index of 0.03 to 0.15 that forms a nip with the developer carrying body. 18. The developing device according to claim 16, wherein the layer thickness regulating member is silicone rubber. 19. A developing step of forming a toner image on an electrostatic latent image carrier, and a transfer of transferring the toner image onto the transfer material while bringing a transfer member to which a voltage is applied into contact with the transfer material. In the image forming method using an electrophotographic apparatus having a step, the toner is SF-1 of 100 to 180, S
F-2 is a toner having a shape factor of 100 to 140 and at least particles in which a colorant is dispersed in a binder resin and an inorganic fine powder, wherein the developer carrying member is at least a substrate and a coating layer. Have
The surface of the substrate is coated with a coating layer, the ten-point average roughness of the surface of the coating layer is Rz (μm), the average particle size of the developer used is r (μm), and the least squares method of the surface of the coating layer is used. when the proportion of the area occupied by the convex portion exceeding the reference plane from 1.5 × r (μm) obtained was S (%) by the following conditions 9μm ≦ Rz ≦ 30μm 1.25 ≦ Rz / r ≦ 6 0 An image forming method characterized by satisfying 0.015 % ≦ S ≦ 1.914 %. 20. The coating layer of the developer carrying member,
20. The image forming method according to claim 19, comprising a coating film in which spherical particles having a volume average particle diameter of 3 to 30 μm are dispersed and contained in a binder resin. 21. The image forming method according to claim 20, wherein the spherical particles in the coating layer of the developer carrying member are resin particles. 22. The image forming method according to claim 20, wherein the spherical particles in the coating layer of the developer carrying member are conductive spherical particles. 23. The image forming method according to claim 19, wherein a conductive fine powder is further dispersed and contained in the coating layer of the developer carrying member to form a conductive coating layer. 24. The image forming method according to claim 19, wherein a solid lubricant is contained in the coating layer of the developer carrying member. 25. The image forming method according to claim 19, wherein the layer thickness regulating member has elasticity. 26. The image forming method according to claim 25, wherein the layer thickness regulating member has an elastic body having a wear index of 0.03 to 0.15 that forms a nip with the developer carrying body. . 27. The image forming method according to claim 25, wherein the layer thickness regulating member is a silicone rubber.