JP2000047420A - Developing method and image forming method - Google Patents

Abstract

(57) [Summary] (with correction) [PROBLEMS] To provide a developing method which is excellent in developability and does not have "negative sleeve ghost" and can obtain a high-quality graphic image. SOLUTION: A negatively chargeable toner 163 is carried on a developer carrier surface 156, and is transported to a developing area formed by the electrostatic latent image carrier 153 and the developer carrier. A developing method of developing a latent electrostatic image with a negatively charged toner carried on the surface of an agent carrier to form a toner image, wherein the negatively charged toner is a toner particle containing a binder resin and a colorant. , Inorganic fine powder and resin fine particles, and the resin fine particles have a number average particle size of 0.1.
05 to 2.00 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing method and an image forming method utilizing electrophotography, electrostatic recording, magnetic recording, and the like. More specifically, the present invention relates to a developing method applied to an image forming apparatus such as a copying machine, a printer, and a facsimile that forms an image by forming a toner image on an electrostatic latent image carrier in advance and transferring the image onto a recording material. The present invention relates to an image forming method.

[0002]

2. Description of the Related Art Conventionally, many methods are known as electrophotography. In general, a photoconductive substance is used to form an electric latent image on a photoreceptor by various means. The latent image is developed into a visible image by developing with toner, and the toner image is transferred to a transfer material such as paper as necessary, and then the toner image is fixed on the transfer material by heat, pressure, etc. to obtain a copy. Things.

As a method for visualizing an electric latent image, a cascade developing method, a magnetic brush developing method, and a pressure developing method are known. Furthermore, a method is known in which a magnetic sleeve is used, and a rotating sleeve having a magnetic pole disposed at the center is used, and the space between the photosensitive member and the sleeve is caused to fly by an electric field.

In recent years, LED and LBP printers have become the mainstream of printer devices, and the direction of technology has increased to higher resolutions, that is, 240,300 dpi in the past, but 400, 600, 800 dpi. Accordingly, higher definition has been required for the developing system. In addition, the functions of the copying machine have been advanced, and the digital copying machine is moving toward digitalization. In this direction, a method of forming an electrostatic charge image with a laser is mainly used, so that the direction is also moving toward a higher resolution, and a high-resolution and high-definition developing method is required similarly to a printer. . For this reason, the particle size of the toner has been reduced,
JP-A-1-112253 and JP-A-2-284158
In Japanese Patent Application Laid-Open Publication No. H11-264, a toner having a specific particle size distribution and a small particle size is proposed.

[0005] As described above, the recent trend is toward higher resolution, but on the other hand, there is an increasing demand for higher quality graphic images. One aspect of the quality of graphic images is the uniformity of image density in solid images.

Regarding the density uniformity of the solid image, in the one-component developing method, when a solid image such as a halftone is printed, an inverted image of the immediately preceding image is printed on the solid image at the cycle of the toner carrier. There is a phenomenon called "negative sleeve ghost" that appears in the above, and there is a problem that the quality of the graphic image is reduced. In order to improve the quality of graphic images, suppression of negative sleeve ghost is required.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a developing method and an image forming method which solve the above-mentioned problems of the prior art.

[0008] That is, an object of the present invention is to provide excellent developability,
An object of the present invention is to provide a developing method and an image forming method capable of obtaining a high-quality graphic image without "negative sleeve ghost".

[0009]

According to the present invention, a negatively chargeable toner is carried on a surface of a developer carrier, and is transported to a developing area formed by an electrostatic latent image carrier and a developer carrier.
In a developing method of forming a toner image by developing an electrostatic latent image carried on the electrostatic latent image carrier with a negatively charged toner carried on the developer carrier in the development region, The developer carrier has a substrate and a coating layer that covers the surface of the substrate, the coating layer comprising: (i) a solid lubricant, a conductive agent, or a mixture of a solid lubricant and a conductive agent;
(Ii) spherical particles having a number average particle diameter of 0.3 to 30 μm, and (iii) a resin, and the moving speed of the surface of the developer carrier in the development area is less than that of the surface of the electrostatic latent image carrier. The moving speed is 1.05 to 2.00 times, and the negatively chargeable toner has toner particles, inorganic fine powder and resin fine particles containing at least a binder resin and a colorant. The particles have a circle-equivalent diameter of 0.60 μm or more and 1.00 μm in the number-based particle size distribution based on the circle-equivalent diameter of the particles measured by the flow-type particle image measurement device.
m is less than 5.0% by number, the equivalent circle diameter is 4 to 10 μm, and the resin fine particles have a number average particle diameter of 0.05 to 2.00 μm. And a developing method.

The present invention also provides an electrostatic latent image forming step of forming an electrostatic latent image on the surface of an electrostatic latent image carrier, and developing the electrostatic latent image by a developing unit to form a toner image. An image forming method having at least a developing step, wherein the developing unit carries a negatively-chargeable toner on a surface of a developer carrying member,
Further, the developer is conveyed to a developing area formed by the electrostatic latent image carrier and the developer carrier, and the negative latent toner carried on the surface of the developer carrier in the developing area carries the electrostatic latent image. Developing the electrostatic latent image carried on the body to form a toner image, wherein the developer carrying body has a substrate and a coating layer covering the surface of the substrate, and the coating layer is ,
(I) a solid lubricant, a conductive agent, or a mixture of a solid lubricant and a conductive agent, (ii) spherical particles having a number average particle diameter of 0.3 to 30 μm, and (iii) a resin, The moving speed of the developer carrier surface in the developing area is 1.05 to 1.05 with respect to the moving speed of the electrostatic latent image carrier surface.
2.00 times, and the negatively chargeable toner has toner particles, inorganic fine powder and resin fine particles containing at least a binder resin and a colorant, and the toner particles are a flow type particle image measuring device. In the number-based particle size distribution based on the equivalent circle diameter of the particles measured by
The content of particles having a particle diameter of not less than 1.00 μm is less than 5.0% by number, the equivalent circle diameter is 4 to 10 μm, and the resin fine particles have a number average particle diameter of 0.05 to 2.00 μm.
And an image forming method.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The particle size distribution of the toner particles according to the present invention in terms of the circle equivalent diameter was measured using a flow particle image analyzer FPIA-1000 manufactured by Toa Medical Electronics Co., Ltd. In this device, the equivalent circle diameter is measured as follows.

In the measurement, fine dust is removed through a filter, and as a result, the measurement range (for example, a circle equivalent diameter of 0.60 μm or more and 159.21 μm) is placed in 10 ⁻³ cm ³ of water.
m) less than 20 particles of water 100-150ml
0.1 to 0.5 ml of a surfactant (preferably an alkylbenzene sulfonate) is added therein, and 0.1 to 0.5 g of a measurement sample is further added. And the particle concentration of the measurement sample is 3000 to 100
0.60 μm using a sample dispersion liquid adjusted to 00/10 ^-3 cm ³ (for particles in a diameter range equivalent to a measurement circle).
The particle size distribution and circularity distribution of the particles having a circle equivalent diameter of less than 159.21 μm were measured, and the circle equivalent diameter was 0.60 μm.
The number-based content and number-average particle diameter of particles having a circle equivalent diameter of less than 1.00 μm are calculated.

The outline of the measurement is described in the catalog of FPIA-1000 (June 1995 version) issued by Toa Medical Electronics Co., Ltd., the operation manual of the measuring device, and Japanese Patent Application Laid-Open No. Hei 8-1364.
No. 39, which is as follows.

The sample dispersion liquid is passed through a flow path (spread along the flow direction) of a flat and flat transparent flow cell (thickness: about 200 μm). The strobe and the CCD camera are mounted on the flow cell so as to be positioned on opposite sides of the flow cell so as to form an optical path that intersects with the thickness of the flow cell. While the sample dispersion is flowing, strobe light is irradiated at 1/30 second intervals to obtain an image of the particles flowing through the flow cell, so that each particle has a range parallel to the flow cell 2
Photographed as a two-dimensional image. The diameter of a circle having the same area is calculated as the equivalent circle diameter from the area of the two-dimensional image of each particle.

In about 1 minute, the equivalent circle diameter of 1200 or more particles can be measured, and the number based on the equivalent circle diameter distribution and the ratio (number%) of the particles having the specified equivalent circle diameter can be measured. . In particular, the particle concentration of the example was 6,000 particles / 10
^In the case of a toner dispersion of ^-3 cm ³ , about 18
One hundred circle equivalent diameters can be measured.

As shown in Table 1, the results (frequency% and cumulative%) can be obtained by dividing the range of 0.06 to 400 μm into 226 channels (30 channels per octave). In the actual measurement, the equivalent circle diameter is 0.
The particles are measured in a range of 60 μm or more and less than 159.21 μm.

[0017]

[Table 1]

Conventionally, there are some devices capable of measuring a particle size of less than 1.00 μm. However, noise has a large effect on a region of less than 1.00 μm, and there is a problem in reproducibility of data. The above-described apparatus is excellent in that reproducibility is good even in a region having a circle-equivalent diameter of less than 1.00 μm, and information as a particle image can be obtained at the same time.

In the present invention, the toner particles have a particle size distribution of 0.60 μm or more in a number-based particle size distribution based on the equivalent circle diameter.
The problem can be solved when the content of particles having a particle diameter of less than 00 μm is less than 5.0% by number and the average circle-equivalent diameter is 4.0 to 10.0 μm.

When the content of particles having a size of 0.60 μm or more and less than 1.00 μm is 5.0% by number or more in the particle size distribution based on the circle equivalent diameter of the toner particles, the amount of the external additive per toner particle is reduced. In addition, the charge amount of the toner before the transfer cannot be sufficiently increased, and the negative sleeve ghost suppression is deteriorated. If the circle-equivalent average diameter is less than 4.0 μm, cleaning failure occurs, and the circle-equivalent average diameter is 10.
If it exceeds 0 μm, so-called filming in which the toner adheres to the photoconductor will occur.

In the production process of the toner, the toner particles are preferably subjected to a treatment for reducing particles having a circle-equivalent diameter of less than 1.00 μm. As a process to reduce
It is more preferable to perform a process of applying a mechanical impact force as described in detail later.

In the particle size distribution according to the circle equivalent diameter of the toner particles in the present invention, the means for easily achieving the content of particles having a particle diameter of 0.60 μm or more and less than 1.00 μm of less than 5.0% by number is as follows. In the present invention, a process for reducing particles having a circle-equivalent diameter of less than 1.00 μm in the present invention is preferably used.

Among the toner particles having a circularity a of not less than 3.00 μm, those having a circularity a of not less than 0.90 are 9 based on the number.
It is preferable that particles having 0% or more and a circularity a of 0.98 or more are less than 30%.

If the circularity a of the toner particles having a circular equivalent diameter of 3.00 μm or more is less than 90% based on the number of particles having a circularity a of 0.90 or more, the adhesion of the toner to the photoreceptor is increased and the transferability is improved. Worsens. Also, the circularity a is 0.9
When the number of particles of 8 or more is 30% or more, cleaning failure occurs.

The circularity a in the present invention is used as a simple method for quantitatively expressing the shape of a particle. For example, a flow type particle image analyzer F made by Toa Medical Electronics Co., Ltd.
Using PIA-1000, the value obtained from the following equation is defined as circularity.

Circularity a = L ₀ / L (L ₀ ; perimeter of a circle having the same projected area as the particle image, L;
Perimeter of particle image)

The circularity distribution of the toner particles in the present invention was calculated by the above equation using the above-described particle image analyzer in the same manner as in the above-described measurement of the equivalent circle diameter.

The toner used in the present invention has an average particle size of the resin fine particles of 0.05 to 2.00 μm, preferably 0.10 to 2.00 μm.
The thickness is preferably up to 1.00 μm.

If the average particle diameter of the resin fine particles is less than 0.05 μm, the adhesion of the fine particles to the toner surface is too large, so that the separation from the toner matrix during development and transfer does not occur sufficiently.
Since the charge amount of the toner before the transfer cannot be increased, the negative sleeve ghost suppression is deteriorated. When the average particle size of the resin fine particles exceeds 2.00 μm, the surface area of the resin fine particles is small, the effect of increasing the charge amount of the toner before transfer is small, and the negative sleeve ghost suppression is deteriorated. Further, aggregation of toner particles may occur with resin fine particles as a nucleus, which may cause an increase in fog.

The content of the resin fine particles in the toner is preferably 0.01 to 0.5% by weight. If the content of the fine particles in the toner is less than 0.01% by weight, the effect of increasing the charge amount of the toner before transfer is insufficient, and the negative sleeve ghost cannot be sufficiently prevented. If the content of the fine particles in the toner exceeds 0.5% by weight, fogging tends to occur.

The fine resin particles have an average particle size of 0.1.
The resin is preferably styrene / o-methylstyrene / m-methylstyrene / p-methylstyrene / p-methoxystyrene / p-
Styrene monomer such as ethylstyrene, acrylic acid
(Meth) acrylic acids such as methacrylic acid, methyl acrylate / ethyl acrylate / n-butyl acrylate / isobutyl acrylate / n-propyl acrylate / n-octyl acrylate / dodecyl acrylate / acrylic acid 2-
Ethylhexyl / stearyl acrylate / acrylic acid 2
Acrylates such as chloroethyl / phenyl acrylate, methyl methacrylate / ethyl methacrylate / n-propyl methacrylate / n-butyl methacrylate / isobutyl methacrylate / n-octyl methacrylate / dodecyl methacrylate / methacrylic acid 2 -Selected from the group consisting of methacrylates such as ethylhexyl, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate and other vinyl monomers such as acrylonitrile, methacrylonitrile, and acrylamide. And benzoguanamine formaldehyde resins and melamine formaldehyde resins.

As a polymerization method for obtaining resin fine particles, suspension polymerization, emulsion polymerization, leap-free polymerization and the like can be used, but particles obtained by soap-free polymerization are more preferable.

The resin fine particles are particularly preferably melamine formaldehyde resin or benzoguanamine-formaldehyde resin among the above exemplified resins. Thereby, the effect of suppressing the negative sleeve ghost is particularly remarkable.

Preferably, a negatively chargeable toner characterized in that the resin fine particles have a positive chargeability is used. When the resin fine particles have positive chargeability, the charge amount of the toner before transfer can be particularly increased, and the effect of suppressing the negative sleeve ghost is further enhanced.

(Measurement of Charging Polarity of Resin Fine Particles) 2 parts by weight of resin fine particles to be measured as a sample and 98 parts by weight of iron powder are mixed for 60 seconds by a turbula mixer. FIG. 7 shows this mixture.
The mixture is placed in a metal container 82 equipped with a 500-mesh conductive screen 83 at the bottom. Then, the potential of the capacitor 88 at that time is set to zero. Then, suction is performed by the suction device 81 through the suction port 87, and the charging polarity is determined from the voltage polarity stored in the capacitor 88 connected to the container 82. That is, since iron powder remains on the 500 mesh and the sample passes through the 500 mesh, for example, when a positive sample is used, a negative voltage remains in the capacitor 83.

In FIG. 6, 84 indicates a lid, 85 indicates a vacuum gauge, and 89 indicates an electrometer. At the time of suction, the suction pressure is set to 250 mmH ₂ O. As iron powder, for example, EFV
200/300 (manufactured by Powder Tech) is used.

(Measurement of Number Average Particle Size of Resin Fine Particles) A sample (0.02 g) was placed in a 5-ml screw tube, and ethanol (3 ml) was added thereto and dispersed in an ultrasonic cleaner for 1 minute. The dispersion sample is placed on a scanning electron microscope sample stage so as to be uniform, and ethanol is volatilized. After sputtering the sample stage, set it on a scanning electron microscope, take two photographs in the same field of view at 20,000 times, and use one for the average particle diameter measurement,
Make one copy for your records. A total of four straight lines of a diagonal line and a cross line are drawn on the photograph for measurement, and 50 clear and easy-to-measure particles on the surface layer are selected along the straight line. The selected particles are measured to 0.01 μm with a caliper linked to a computer, and the average particle diameter is determined.

On the other hand, the developer carrying member according to the present invention is required to have a surface moving speed of 1.05 to 2.00 times the moving speed of the surface of the electrostatic latent image carrier. In particular, it is preferable that the moving speed of the developer carrier is 1.2 to 2.0 times the moving speed of the surface of the electrostatic latent image carrier.

If the moving speed of the developer carrying member is less than 1.05 with respect to the moving speed of the surface of the electrostatic latent image carrying member, a portion requiring a large amount of toner for development over a wide area such as solid black may be used. In some cases, the toner supply to the latent image is insufficient,
Image density decreases. If the ratio is more than 2.00, the toner may deteriorate and the toner may adhere to the developer carrier, which is not preferable.

Further, by using the above-mentioned developer carrying member, the charging ability is stabilized, the charge amount of the toner is uniform, and a desired value is obtained.

The developer carrier used in the present invention is used as a developing sleeve in a developing device. The developer carrier used in the present invention has a substrate such as cylindrical aluminum and a coating layer covering the surface of the substrate. The coating layer comprises a solid lubricant, a conductive agent or a mixture of a solid lubricant and a conductive agent.
It has at least spherical particles having a number average particle diameter of 3 to 30 μm and a binder resin.

The solid lubricant used in the present invention is preferably graphite, and the conductive agent is preferably carbon black.

The spherical particles are added, for example, to prevent the broken surface of graphite from becoming smooth. In particular, even when the coating layer of the developer carrying member is worn, a uniform surface roughness is obtained. It is added to maintain the degree. If the number average particle diameter of the spherical particles is less than 0.3 μm, there is no effect of the surface roughness. "Spherical" in the present invention,
The particles have a ratio of major axis / minor axis of 1.0 to 1.5, and the ratio of major axis / minor axis is preferably 1.0 to 1.2.
In particular, true spherical particles are preferable.

In the present invention, the average particle size of the spherical particles is measured by using a Coulter Co., Ltd .:
0 μm aperture (50 μm for particles less than 3.0 μm
). The conductive particles were measured by attaching a liquid module to a LA-130 type particle size distribution analyzer manufactured by Coulter Corporation.

As the binder resin layer used in the resin layer of the present invention, generally known resins can be used. For example,
Phenolic resin, epoxy resin, polyamide resin, polyester resin, polycarbonate resin, polyolefin resin, silicone resin, fluorine resin, styrene resin, vinyl resin, cellulose resin, melamine resin, urea resin Resin, polyurethane-based resin, polyimide-based resin, acrylic resin, and the like. A curable resin is more preferable in consideration of mechanical strength, but a thermoplastic resin is also applicable as long as it has sufficient mechanical strength.

As a material added to the resin layer of the present invention to impart conductivity to the resin layer, generally known conductive fine powder can be mentioned. For example, powders of metals or alloys such as copper, nickel, silver, and aluminum; metal oxides such as antimony oxide, indium oxide, tin oxide, and titanium oxide; and carbon-based conductive materials such as carbon fiber, carbon black, and graphite. No. The amount of the conductive fine powder to be added varies depending on the development system. For example, in the case of using a one-component insulating developer in a jumping development method, the resin layer is preferably adjusted to 10 ³ Ω · cm or less. It is preferred to add. Carbon black, especially conductive amorphous carbon, is particularly excellent in electric conductivity, and can provide conductivity with a small amount of addition compared to others, and it is possible to obtain an arbitrary resistance to some extent by controlling the amount of addition. Therefore, it is preferably used.

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

As the spherical resin particles, for example, spherical resin particles obtained by a suspension polymerization method, a dispersion polymerization method or the like are used. Spherical resin particles can obtain a suitable surface roughness with a smaller addition amount, and can easily obtain a more uniform surface shape.
Examples of such spherical resin particles include acrylic resin particles such as polyacrylate and polymethacrylate, polyamide resin particles such as nylon, polyolefin resin particles such as polyethylene and polypropylene, silicone resin particles, and phenolic resin particles. Examples include polyurethane resin particles, styrene resin particles, and benzoguanamine particles. The resin particles obtained by the pulverization method may be used after being subjected to thermal or physical sphering treatment.

For example, an inorganic fine powder is applied to the surface of spherical resin particles.
The powder may be adhered or fixed. This
As inorganic fine powders such as_Two, SrTiO_Three,
CeO_Two, CrO , Al_TwoO_ThreeAcids such as ZnO, ZnO and MgO
Compound, Si_ThreeN_FourSuch as nitride, carbide such as SiC, C
aSO_Four, BaSO_Four, CaCO_ThreeSulfates and carbonates such as
And the like.

Such an inorganic fine powder may be used after being treated with a coupling agent. In particular, it can be preferably used for the purpose of improving the adhesion to the binder resin or for imparting hydrophobicity to the particles. Examples of such a coupling agent include a silane coupling agent, a titanium coupling agent, a zircoaluminate coupling agent, and the like. More specifically, for example, as the silane coupling agent, hexamethyldisilazane,
Trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β -Chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1, 3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane and one molecule For example, dimethylpolysiloxane having from 2 to 12 siloxane units and containing hydroxyl groups bonded to up to one silicon atom in each of the units located at the terminals can be used.

By treating the surface of the spherical resin particles with the inorganic fine powder, dispersibility in the coating material, uniformity of the coating surface, stain resistance of the film, charge imparting property to the toner, coating The wear resistance of the layer can be improved.

It is also possible to use conductive spherical particles in order to make the spherical particles have stain resistance, wear resistance and the like. As the conductive spherical particles, for example, conductive conductive spherical particles, such as titanium oxide, niobium oxide, manganese oxide, zinc oxide and other metal oxides, and barium sulfate and other pigments, and conductive oxides such as tin oxide There is a material coated with a conductive material; or a material obtained by doping a metal having a different oxidation number into an insulating metal oxide such as zinc oxide, copper oxide, or iridium oxide to have conductivity.

The volume resistivity of the conductive spherical particles is 10 ⁶ Ω · c.
m or less. If it exceeds 10 ⁶ Ω · cm, prevention of toner contamination may not be sufficient.

The true density of the spherical particles to be added is 3 g / c
Those having m ³ or less are preferred. If the true density exceeds ³ g / cm ³ , the dispersibility of the spherical particles in the conductive coating layer may be insufficient, so that it is difficult to impart uniform roughness to the surface of the coating layer, and the toner may be uniformly dispersed. There is a possibility that the application of a sufficient charge and the strength of the coating layer may become insufficient, and furthermore, the durability, contamination resistance and abrasion resistance of these particles may not be exhibited. Examples of the type of conductive spherical particles satisfying such conditions include spherical carbon particles, spherical resin particles surface-treated with a conductive substance, and spherical resin particles in which conductive fine particles are dispersed.

The spherical carbon particles are obtained by firing resin-based spherical particles such as phenolic resin, naphthalene resin, furan resin, xylene resin, divinylbenzene polymer, styrene-divinylbenzene polymer, polyacrylonitrile, and mesocarbon microbeads. The particles are preferably made into particles of low density and good conductivity by being graphitized and / or graphitized, and more preferably those whose surface is further graphitized to improve conductivity and lubricity.

As a method of treating the surface of the spherical resin particles with a conductive material, for example, a method in which conductive fine particles smaller than the diameter of the core particles are mechanically mixed on the surface of the core particles composed of the spherical resin particles at an appropriate mixing ratio. After the conductive fine particles are uniformly attached around the resin particles by the action of van der Waals force and electrostatic force, for example, the surface of the resin particles is softened by a local temperature rise caused by a mechanical impact force, etc. Conductive treated spherical resin particles on which fine particles have been formed are exemplified. As a constituent material of the base particles, it is preferable to use a resin that is a spherical organic compound having a low core density. For example, PMMA, an acrylic resin, a polybutadiene resin, a polystyrene resin, polyethylene, polypropylene, polybutadiene, or a combination thereof. Resin particles such as a polymer, a benzoguanamine resin, a phenol resin, a polyamide resin, nylon, a fluorine resin, a silicone resin, an epoxy resin, and a polyester resin can be used. In addition, the diameter of the base particles having a diameter of small particles is 1 /
It is preferably 8 or less.

As a method for producing a resin in which conductive fine particles are uniformly dispersed in spherical resin particles, for example, conductive fine particles are dispersed and kneaded in a binder resin, and then pulverized to a predetermined particle size. Monomer composition obtained by adding a polymerization initiator, conductive fine particles and other additives to a conductive spherical particle or a polymerizable monomer, which has been made spherical by treatment and thermal treatment, and uniformly dispersed by a disperser or the like. Suspended in a water phase containing a dispersion stabilizer to a predetermined particle size by a stirrer or the like,
Spherical particles dispersed with conductive fine particles obtained by performing polymerization are exemplified. Spherical particles of conductive fine particles dispersed by these methods are mechanically mixed with conductive fine particles having a particle size smaller than the core particles at an appropriate mixing ratio, and by the action of van der Waals force and electrostatic force, After the conductive fine particles are uniformly attached around the spherical particles dispersed in the conductive fine particles, the surface of the resin particles dispersed in the conductive fine particles is softened by a local temperature rise caused by, for example, a mechanical impact force, and the conductive fine particles are formed. It may be used by forming a film and further increasing the conductivity.

As the base of the developer carrier used in the present invention, metals and alloy compounds can be preferably used. In addition, non-metallic materials can be used.

However, in the structure of the present invention, since the developing sleeve is used as an electrode, when a non-metallic material, for example, a plastic molded product is used, it is necessary to make the structure capable of conducting electricity. For example, a metal is adsorbed on the surface of the developer carrying member by vapor deposition, or a conductive resin is used.

As the graphite used in the present invention, any of natural products and artificial products can be used.

The particle size of graphite is scale-like and cannot be specified unconditionally. As will be described later, it is difficult to indicate the range of the particle size of graphite due to a change in shape when dispersed by a stirring means such as a sand mill. The width (in the plane direction) is preferably 100 μm or less.

As a measuring method, a method of directly observing a sample with a microscope is the most preferable method. As a simple method, there is a method in which measurement is performed with a general particle size distribution meter (electric resistance type, sedimentation type, centrifugal type, laser scattering type, etc.) to obtain the maximum value.

The degree of graphitization of graphite is 60%
It is preferable that it is above. This is because the degree of graphitization is a characteristic that affects the susceptibility to cracking, and is a characteristic that is considered to affect the difference between the initial state and the endurance state in the film characteristic.

There are various methods for measuring the degree of crystallinity, but evaluation by X-ray diffraction is common and reproducibility is good.

As the carbon black used in the present invention, any of a furnace type and a channel type can be used. Among them, a substance having a low resistance is preferable in consideration of the characteristics of the film, and a carbon black having a resistance value of 0.5 Ω · cm or less under a pressure of 120 kg / cm ^{2 is} particularly preferable.

The addition amount W of carbon black is expressed by the formula W = {100 / (oil absorption of carbon black)} × 10 with respect to 100 parts by weight of the binder resin.
It is preferable to satisfy 0 × a.

However, the carbon black oil absorption was measured for sample 10
0 g of oil absorption of dibutyl phthalate [cc / 10
0g] (ASTM D-2414-79), and the coefficient a indicates 0.3 to 3. It is also possible to use several types of carbon black in combination, and in that case, the oil absorption is determined by actually measuring the mixture.

When the coefficient a is less than 0.3, the effect of adding carbon black is not recognized, and when the coefficient a exceeds 3, the coating hardness is undesirably reduced.

The addition amount of carbon black is preferably such that the coefficient a satisfies 0.5 to 2.

Next, a method for producing the developer carrier of the present invention will be described.

The coating agent used in the present invention is a raw material of the coating agent so as to have a solid content of 5 to 50% by weight in a solvent soluble in a binder resin, for example, an alcoholic solvent such as methanol or propyl alcohol with respect to a phenol resin. And the pigment content is dispersed with a stirrer such as a sand mill, a ball mill, and an attritor to obtain a stock solution of a coating agent. A solvent is added to this coating agent stock solution, and the solid content is adjusted to a production method to obtain a coating solution. This coating liquid is applied on a developer carrier base,
After touch drying, the coating layer is cured by heating or exposure to form a developer carrier. As the application method,
Spraying, dipping, roller coating, bar coating, and electrostatic coating are used.

Next, the composition ratio of each component used in the present invention will be described. The following are particularly preferred ranges.

In the present invention, a particularly preferable result is obtained when the weight ratio of (graphite) / (binder resin) is in the range of 2/1 to 1/3. If it is larger than 2/1, the film strength is reduced, and if it is smaller than 1/3, there is a high possibility that an illegal coating of the developer due to the influence of the binder resin occurs.

In the present invention, the addition amount of the spherical particles is particularly preferably in the range of 1 to 20% by weight based on the weight of the binder resin. If it is less than 1%, the effect of adding the spherical particles is small, and if it exceeds 20%, the developing characteristics may be adversely affected.

In the present invention, the following additives may be further added to the film. A conductive substance may be added to adjust the resistance of the coating. Conductive carbons such as acetylene black and oil black;
Metal powders such as iron, lead and tin; metal oxides such as tin oxide and antimony oxide. The amount of the additive can be used in the range of the additive substance / binder resin ratio of 12/1 to 1/3.

In order to further stabilize the charge of the toner, a charge control agent used for the toner may be added to the film.
For example, nigrosine, quaternary ammonium salts, boric acid compounds, phosphoric acid compounds and the like can be mentioned. In any case, by adding the spherical particles having a particle diameter of 0.3 to 30 μm according to the invention, a stable developer-carrying member surface can be maintained.

The roughness of the surface of the developer carrying member in the present invention is 0.2 to 5.0 μm as an area average value (hereinafter referred to as Ra).
(Preferably 0.3 to 3.0), and a rate of change in surface roughness due to durability (after / early durability) of 0.5
２．０2.0 μm. If the surface roughness is less than 0.2 μm, the carrying capacity is decreased, which is not preferable. If the surface roughness is more than 5.0 μm, the developer coat layer becomes thick, and scattering and illegal development become unfavorable. The rate of change of the roughness is measured to confirm that the change in the surface roughness due to the durability achieved by the present invention is small.

On the surface of the developer carrying member, the relationship between the average pitch of roughness (Sm), which is the average interval of the irregularities on the surface of the coating film, and the average particle size (d) of the toner of the developer is expressed by S
m / d = 1/10 to 10, preferably 1/5 to 5, and the roughness (Ra) of the coating surface is preferably 0.3 to 3 μm, and more preferably 0.5 to 3 μm.

Length direction (Sm value) and height direction (Ra value)
Were used as representative values of the surface state. Here, when the Sm / d value is smaller than 1/10, the roughening effect does not appear. When the Sm / d value is more than 10, the surface becomes close to a smooth surface with respect to the toner size.

In the present invention, the center line average roughness (Ra)
Is measured based on JIS surface roughness (B0601) using a surface roughness measuring device (Surfcoder SE-30H, Kosaka Laboratory Co., Ltd.). Specifically, the center line average roughness (Ra) is obtained by extracting a portion of 12.5 mm as the measured length a from the roughness curve in the direction of the center line, setting the center line of the extracted portion as the X axis and the vertical magnification. Is the Y-axis, and the roughness curve is y = f (x), and the value obtained by the following equation is expressed in micrometers (μm).

[0081]

(Equation 1)

In the present invention, the average interval (S
m) is Sm = L / n (where L is a reference length and 2.
5 mm, and n indicates the number of peaks). Mountain number n
Sets two peak count levels (± 0.21 μm) parallel to the center line of the roughness curve, and sets the upper peak count level and the curve between two points where the lower peak count level and the curve intersect. The number n of the peaks is defined as a reference length (2.5 mm) as one peak at which the point where
Ask between.

In order to accelerate the release of the developer from the surface of the developer carrier, a material having a low surface energy may be added. For example, a fluorine compound, boron nitride, graphite and the like can be mentioned.

Examples of the kind of the binder resin of the toner used in the present invention include homopolymers of styrene and its substituted substances such as polyethylene, poly-p-chlorostyrene and polyvinyltoluene, and styrene-p-chlorostyrene. Copolymer, styrene-vinyltoluene copolymer, styrene-
Vinyl naphthalene copolymer, styrene-acrylate copolymer, styrene-methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-
Styrene such as vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer -Based copolymer; polyvinyl chloride; phenolic resin; natural modified phenolic resin; natural resin modified maleic acid resin; acrylic resin; methacrylic resin; polyvinyl acetate; silicone resin; polyester resin; A xylene resin; a polyvinyl butyral; a terpene resin; a cumarone indene resin; Crosslinked styrenic resins are also preferred binder resins.

As a comonomer for the styrene monomer of the styrene copolymer, a vinyl monomer can be used alone or in combination of two or more. Examples of the vinyl monomer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, Ethyl methacrylate, butyl methacrylate,
Monocarboxylic acid having a double bond such as octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide or a substituted product thereof; for example, maleic acid,
Dicarboxylic acids having a double bond such as butyl maleate, methyl maleate and dimethyl maleate, and substituted products thereof; for example, vinyl esters such as vinyl chloride, vinyl acetate and vinyl benzoate; for example, ethylene, propylene, butylene Ethylene-based olefins such as vinyl methyl ketone and vinyl hexyl ketone; and vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether. Here, as the crosslinking agent, a compound having two or more polymerizable double bonds is mainly used, and it can be used alone or in combination of two or more. Examples of such a compound include aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; and carboxylic acids having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate and 1,3-butanediol dimethacrylate. Acid esters: divinylaniline, divinylether,
Divinyl compounds such as divinyl sulfide and divinyl sulfone; and compounds having three or more vinyl groups can be used alone or as a mixture.

As the colorant used in the present invention, a black colorant that uses carbon black, a magnetic substance, and the following yellow / magenta / cyan colorants as a black colorant is used.

As the yellow colorant, condensed azo compounds, isoindolinone compounds, anthraquinone compounds,
A compound represented by an azo metal complex, a methine compound or an allylamide compound is used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 6
2, 74, 83, 93, 94, 95, 97, 109, 1
10, 111, 120, 127, 128, 129, 14
7, 168, 174, 176, 180, 181, 191
Etc. are preferably used.

Examples of the magenta colorant include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds and perylene compounds. Specifically, C.I.
I. Pigment Red 2, 3, 5, 6, 7, 23, 4
8: 2, 48: 3, 48: 4, 57: 1, 81: 1, 1
44, 146, 166, 169, 177, 184, 18
5, 202, 206, 220, 221, 254 are particularly preferred.

As the cyan coloring agent, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds and the like can be used. Specifically, C.I. I.
Pigment Blue 1, 7, 15, 15: 1, 15: 2,
15: 3, 15: 4, 60, 62, 66 can be particularly preferably used.

These colorants can be used alone or as a mixture, or in the form of a solid solution. The colorant of the present invention is selected from the viewpoints of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in toner. The colorant is used in an amount of 1 to 20 parts by weight based on 100 parts by weight of the resin.

When a magnetic material is used as a black colorant, unlike other colorants, 30 parts per 100 parts by weight of resin is used.
Used in an amount of up to 200 parts by weight.

As the magnetic material, there is a metal oxide containing an element of iron, cobalt, nickel, copper, magnesium, manganese, aluminum or silicon. Among them, ferric oxide,
Those containing iron oxide as a main component, such as γ-iron oxide, are preferred. From the viewpoint of controlling the chargeability of the toner, another metal element such as a silicon element or an aluminum element may be contained. These magnetic particles, BET specific surface area by nitrogen adsorption method preferably 2 to 3 m ² / g, especially 3~28m ² / g
The Mohs' hardness is preferably 5 to 7.

The shape of the magnetic material is octahedron, hexahedron,
There are spherical, needle-like and scale-like, but octahedral, hexahedral, spherical,
An amorphous type having a small anisotropy is preferable for increasing the image density.

The average particle size of the magnetic material is 0.05 to 1.
0 μm is preferable, and 0.1 to 0.6 μm is more preferable.
m, more preferably 0.1 to 0.4 μm.

The amount of the magnetic substance is 3 with respect to 100 parts by weight of the binder resin.
0 to 200 parts by weight, preferably 40 to 200 parts by weight, more preferably 50 to 150 parts by weight. If the amount is less than 30 parts by weight, in a developing device that uses a magnetic force to transport the toner, the transportability is insufficient, and the developer layer on the developer carrier tends to be uneven, resulting in image unevenness. , The image density tends to decrease. On the other hand, if it exceeds 200 parts by weight, a problem tends to occur in the fixing property.

In the present invention, if necessary, wax may be internally added to the toner particles. Examples of the wax used include polypropylene, polyethylene, microcrystalline wax, carnauba wax, sasol wax, paraffin wax, higher alcohol wax, ester wax, and oxides and graft-modified products thereof.

These low-molecular-weight waxes may be added and mixed in the binder resin in advance during the production of the toner. The addition amount is preferably about 1 to 20 parts by weight based on 100 parts by weight of the binder resin.

In the toner of the present invention, a charge control agent may be blended (internally added) to the toner particles or mixed (externally added) with the toner particles, if necessary. The charge control agent makes it possible to control the amount of charge optimally according to the development system. In particular, in the present invention, the balance between the particle size distribution and the amount of charge can be further stabilized.

The following substances control the toner to be negatively charged. For example, an organic metal complex or a chelate compound is effective, and examples thereof include a monoazo metal complex, an acetylacetone metal complex, an aromatic hydroxycarboxylic acid, and an aromatic dicarboxylic acid-based metal complex. Other examples include aromatic hydroxycarboxylic acids, aromatic monocarboxylic acids, aromatic polycarboxylic acids and their metal salts, their anhydrides, their esters, and phenol derivatives such as bisphenol.

The charge control agent described above is preferably used in the form of fine particles. In this case, the number average particle diameter of these charge control agents is 4 μm or less, preferably 3 μm or less, more preferably 0.5 to 3 μm. Is good. When these charge control agents are internally added to the toner, the binder resin 10
0.1 to 20 parts by weight relative to 0 parts by weight, particularly 0.2 to 20 parts by weight
It is preferable to use 10 parts by weight.

Examples of the external additive of the inorganic fine powder used in the toner of the present invention include inorganic fine powders such as silica, alumina, and titania, or a combination thereof, in order to improve charge stability, developability, fluidity, and storage stability. Oxides are preferred. Further, silica is more preferable. For example, as the silica, both a so-called dry method produced by vapor-phase oxidation of a silicon halide and an alkoxide, and a so-called wet silica produced from dry glass and alkoxide called fumed silica and water glass can be used. However, dry silica having less silanol groups on the surface and in the interior of the silica fine powder and having less production residues such as Na ₂ O and SO ₃ ^2- is preferred. In the case of fumed silica, for example, it is also possible to obtain a composite fine powder of silica and another metal oxide by using another metal halide such as aluminum chloride and titanium chloride together with a silicon halide in the production process. Is also included.

The inorganic fine powder used in the present invention is BET.
Law in specific surface area according to the measured nitrogen adsorption 30 m ² / g or more, the silica fine powder of 0.1 to 8 weight especially for 50 to 400 m ² / g is 100 parts by weight of the toner particles gave good results in the range of Particular preference is given to using from 0.5 to 5 parts by weight, more preferably from more than 1.0 to 3.0 parts by weight.

The inorganic fine powder used in the present invention may be, if desired, a silicone varnish, for the purpose of hydrophobicity and charge control.
Treatment with silicone oil, various modified silicone oils, silane coupling agents, silane coupling agents having functional groups, and other treating agents such as organosilicon compounds and organotitanium compounds alone or in combination. Is preferred.

According to the BET method, the specific surface area was measured by adsorbing nitrogen gas on the sample surface using a specific surface area measuring apparatus Autosorb 1 (manufactured by Yuasa Ionics) and calculating the specific surface area using the BET multipoint method.

In order to maintain stable storage stability of the toner, the inorganic fine powder is preferably treated at least with silicone oil.

An external additive other than the silica fine powder may be added to the toner of the present invention, if necessary.

For example, a charge auxiliary agent, a conductivity-imparting agent, a fluidity-imparting agent, an anti-caking agent, a release agent for fixing with a hot roll,
These are resin fine particles that function as a lubricant, an abrasive, and the like.

In general, to prepare a toner, for example,
Binder resin, pigment as a colorant, dye, or magnetic material,
If necessary, a wax, a metal salt or a metal complex, a charge control agent and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill, and then melted using a heat kneader such as a heating roll, a kneader or an extruder. While kneading to make the resins compatible with each other, disperse or dissolve the colorant, metal compounds, pigments, and dyes as necessary, solidify by cooling, pulverize, and perform classification and surface treatment as necessary. A method in which toner particles are obtained, and a resin fine particle, an inorganic fine powder, and the like are added and mixed to produce the toner particles is preferably used.

As a means for applying a mechanical impact force to the toner of the present invention, for example, a method using a mechanical impact pulverizer such as a Kryptron system manufactured by Kawasaki Heavy Industries and a turbo mill manufactured by Turbo Kogyo, or a method manufactured by Hosokawa Micron Corporation Like a mechanofusion system or a hybridization system manufactured by Nara Machinery Co., Ltd., the toner is pressed against the inside of the casing by centrifugal force using high-speed rotating blades.
A method of applying a mechanical impact force to the toner by a compressive force / frictional force may be used. Specifically, in order to obtain the toner of the present invention, for example, a turbo mill manufactured by Turbo Kogyo Co., Ltd., which is a mechanical impact pulverizer shown in FIG. / M to 150m /
A method in which the rotor 114 is rotated within about a second to adjust the circularity distribution and the particle size distribution while finely pulverizing the toner, or in addition to this, a method of performing a surface treatment by a mechanical impact force is preferable.

It is particularly preferable to apply a mechanical impact force after the finely pulverizing step of the toner or after the classification step, in order to enhance the suppression of the negative sleeve ghost.

The mechanical impact type pulverizer shown in FIG. 4 has a vertical direction in which four processing blades 121 are horizontally mounted on a horizontal disk as shown in a sectional view of FIG. A surface reforming apparatus I of a system that gives a mechanical impact force and has a processing chamber 1 in which a rotating rotor 114 is arranged in four stages along a rotating shaft 115 extending in a horizontal direction is used. As a specific method of the surface treatment, each rotor 114 is moved at a peripheral speed of 40 m /
As shown in FIG. 3, a cyclone 20 and a blower 24 are attached to the outlet side of the surface reforming apparatus I, and suction is performed at a blower air volume of 3.0 m ² . The toner in the toner container 40 is supplied from the inlet 111 at a speed of 20 kg / h by the auto feeder 15 to perform the surface treatment of the toner. The toner introduced into the processing chamber 1 of the surface reforming device is subjected to an impact force when passing through the minute gap 113 between the rotating processing blade 121 and the inner wall of the processing chamber 1 and subjected to spheroidizing processing.

The surface-treated toner passes from the outlet 10 through the cyclone inlet 19 and is collected by the rotary valve 21. In addition, the bug fine powder of the toner passes through the bag filter 22 and is collected by the rotary valve 23.

In the impact type surface treatment apparatus, as shown in FIGS. 2 and 3, the rotating shaft 61 is driven by a driving means, and the rotating disk 62 is driven at a peripheral speed such that the particles are not crushed due to the nature of the material to be surface-treated. Is rotated, and a rapid airflow generated by the rotation of the rotating disk causes a circulating flow returning to the center of the rotating disk 62 through a circulation path 63 opened to the shock chamber 68.

Next, a predetermined amount of powder to be processed is charged from the raw material hopper 64 into the impact chamber 68, and the charged powder to be processed is instantaneously hit by the rotating disk 62 which rotates at a high speed. After receiving the impact action by rushing into the collision ring 58, the circulating flow returns to the impact chamber 68 again through the circulation path 63, and the surface treatment is performed again by the impact action. It is preferable to rotate the turntable so that the peripheral speed of the blade 55 is in the range of 60 m / sec to 150 m / sec.

Either the classification or the surface treatment may be performed first. In the classification step, it is preferable to use a multi-division classifier in terms of production efficiency.

A preferred embodiment of the image forming method of the present invention will be described with reference to FIG.

The surface of the OPC photosensitive drum 153 serving as an electrostatic latent image holding member is negatively charged by a contact charging member 161 including a charging roller serving as a primary charger, and is digitally scanned by image scanning by exposure 155 using a laser beam. Negative triboelectrification of a developing device 151 as a developing unit that forms a latent image and includes a developing sleeve (toner carrier) 156 including a urethane rubber elastic blade 158 and a magnet 165 disposed in the counter direction. The electrostatic latent image is reversely developed with the magnetic toner 163. Or
Using an amorphous silicon photoconductor, the amorphous silicon photoconductor is charged to a positive polarity to form an electrostatic latent image, and regular development is performed using a negative frictionally chargeable magnetic toner. An alternating bias, a pulse bias, and / or a DC bias are applied to the developing sleeve 156 by a bias applying unit 162. When the recording paper P as the recording material is conveyed and reaches the transfer section, the recording paper P is charged from the back surface (the surface opposite to the photosensitive drum side) by the contact transfer member 154 including a transfer roller as a transfer unit. The toner image on the photosensitive drum surface is electrostatically transferred onto the recording paper P.
The recording paper P separated from the photosensitive drum 153 is supplied to a fixing roller 171 and a pressure roller 172 of a heat and pressure fixing device having a fixing roller 171 having a heating unit 170 therein and a pressure roller 172 pressed against the fixing roller 171.
The fixing process is performed to fix the toner image on the recording paper P by passing through the pressure contact portion of the recording paper P.

The toner remaining on the photosensitive drum 153 after the transfer step is removed by a cleaning device 164 having a cleaning blade 157. After the cleaning, the photosensitive drum 153 is neutralized by the erase exposure 160, and the process starting from the charging process by the primary charger 161 is repeated again.

The electrostatic latent image holding member (photosensitive drum) has a photosensitive layer and a conductive substrate, and moves in the direction of the arrow. A non-magnetic cylindrical developing sleeve 156, which is a developer carrying member, rotates so as to advance in the same direction as the surface of the electrostatic latent image holding member in the developing area. Inside the non-magnetic cylindrical developing sleeve 156, a multi-pole permanent magnet 165 (magnet roll) as a magnetic field generating means is arranged so as not to rotate. Developing device 151
The toner 163 is applied on the non-magnetic cylindrical surface, and the toner particles are given a negative triboelectric charge by friction between the surface of the developing sleeve 156 and the toner particles.
Further, by disposing the elastic doctor blade 158, the thickness of the developer layer is regulated to be thin (30 μm to 300 μm) and uniform, so that the toner layer which is thinner than the gap between the photosensitive drum 153 and the developing sleeve 156 in the developing section is not formed. It is formed so as to be in contact. By adjusting the rotational speed of the sleeve 156, the surface speed of the sleeve is substantially equal to or close to the speed of the surface of the electrostatic latent image holding member.

An AC bias or a pulse bias may be applied to the developing sleeve 156 by the bias means 162. This AC bias is f 200-4,000H
It is preferable that z and Vpp are 500 to 3,000 V.

When the toner particles are transferred in the developing area, the toner particles are transferred to the electrostatic latent image side by an electrostatic force on the surface of the photosensitive drum 153 holding the electrostatic latent image and the action of an AC bias or a pulse bias.

[0122]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Production Examples and Examples, but this does not limit the present invention in any way. All parts in the following formulations are parts by weight.

(Toner Production Example 1) 100 parts of styrene-butyl acrylate-butyl maleate half ester copolymer 100 parts of magnetic material (average particle size 0.24 μm) 100 parts Iron complex of monoazo dye (control of negative chargeability) 1.5 μm) 2 parts ・ Low molecular weight polyethylene (differential thermal analysis endothermic peak 104 ° C) 4 parts

The above materials were mixed in a blender,
The mixture was melt-kneaded with a twin-screw extruder heated to 0 ° C., and the cooled kneaded material was roughly pulverized with a hammer mill, and the coarse pulverization was finely pulverized with a pulverizing means having an air classifier and a collision type air pulverizer. The obtained finely pulverized material is compressed with a compressed air of 2.0 kg / cm ² by a multi-segment classifier using a Coanda effect which has a built-in forced powder dispersion device using compressed air in a powder supply section. Supplied while forcibly dispersing and strictly classifying, the ratio of particles having a number average circle equivalent diameter of 6.2 μm and a circle equivalent diameter of 0.60 μm or more and less than 1.00 μm occupies 3.7% of the total number of the particles. Was obtained.

Further, the magnetic toner particles were subjected to a surface treatment using a surface reforming apparatus of a type in which a rotor was rotated to give a mechanical impact force. The number average circle equivalent diameter of the obtained toner particles 1 is 6.4 μm, and the circle equivalent diameter is 0.60 μm or more and 1.0 or more.
The ratio of the particles occupying less than 0 μm is 0.
7%, particles having a circularity a of 0.90 or more are 9
Particles having 5.2% and circularity a of 0.98 or less were 24.0% on a number basis.

To the obtained toner particles 1, 0.1% of the resin fine particles a shown in Table 2 and 1.2% of silicone oil and dry silica treated with hexamethyldisilazane were added, and mixed with a mixer. 1 was obtained.

(Toner Production Examples 2 and 3, Comparative Toner Production Example 1)
Toners 2 to 4 shown in Table 4 were obtained in the same manner as in Toner Production Example 1 except that resin fine particles b to d shown in Table 3 were used.

(Toner Production Examples 4 and 5) Toner Production Example 1
Toners 5 and 6 shown in Table 4 were obtained in the same manner as in Toner Production Example 1, except that the amount of the resin fine particles a added in the step was changed to the amount shown in Table 4.

(Toner Production Example 6) A toner production example 6 was carried out in the same manner as the toner production example 1 except that the surface treatment was not performed by mechanical impact.
Thus, Toner 7 shown in Table 4 was obtained. Table 2 shows the physical properties of the toner particles 2 obtained in the production process.

(Toner Production Example 7, Toner Comparative Production Example 2)
Except that the resin fine particles added in toner production example 1 were resin fine particles e or f shown in Table 3, toner production example 1
In the same manner as in the above, toners 8 and 9 shown in Table 4 were obtained.

(Comparative Toner Production Example 3) The amount of the magnetic substance in Toner Production Example 1 was changed to 50 parts, and in the classification step, the toner was not supplied with compressed air at the time of toner supply, and surface treatment was also performed by mechanical impact. A toner 10 shown in Table 4 was obtained in the same manner as in Toner Production Example 1 except for the absence. Table 2 shows the physical properties of the toner particles 3 obtained in the production process.

(Comparative Toner Production Example 4) Table 4 was prepared in the same manner as in Toner Comparative Production Example 3 except that 0.6 parts of resin fine particles f were added instead of resin fine particles a to be added in Comparative toner production example 3. The following toner 11 was obtained.

(Production Example of Developer Carrier) Production Example-a: 200 parts of resole type phenol resin solution (containing 50% methanol) 45 parts of graphite having a number average particle diameter of 6.1 μm 45 parts of conductive carbon black・ Isopropyl alcohol 130 parts

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

Next, 5 parts of conductive spherical carbon particles (number-average particle diameter 6.1 μm) were added to 380 parts of the stock solution a, and isopropyl alcohol was added so that the solid concentration became 32%. Was dispersed for 1 hour using glass beads, and the beads were separated using a sieve to obtain a coating liquid.

Using this coating solution, a coating layer is formed on an aluminum cylindrical tube having a diameter of 20 mm by a spray method, and then cured by heating at 150 ° C. for 30 minutes in a hot air drying furnace to form a developer carrier a. Was prepared. The adhesion weight of the coating layer after drying was 100 mg / cm ² . The surface roughness (Ra) of the coating layer on the formed aluminum substrate is 2.
It was 5 μm.

Production Example-b: In Production Example-a, PMMA (number average particle diameter of 13.2) was used instead of the conductive spherical carbon particles.
A developer carrying member b was produced in the same manner as in Production Example a except that 4 μm) was used.

Comparative Production Example-c: Surface roughness equivalent to that of Production Example-a (Ra =
(2.5 μm), the surface was roughened by sandblasting.

Comparative Production Example-d: Among the materials in Production Example-a, the number average particle diameter of the conductive spherical carbon particles was 40 μm.
A developer carrier was produced in the same manner as in Production Example-a, except that the following conditions were used.

Comparative Production Example-e: A developer carrier was produced in the same manner as in Production Example-b, except that the number average particle diameter of PMMA was 0.02 μm among the materials in Production Example-b.

[Evaluation of Image] Evaluation was performed using the following developing device.

As the developer carrier, the developer carrier described in the production example was used. Further, a quadrupole magnet having a magnetic flux density of a developing pole of 90 mT was incorporated in the cylindrical sleeve.

The developer regulating member has a thickness of 1.55 m.
m silicone rubber blade and 2
They were brought into contact with each other with a drawing pressure of 6.4N.

The photosensitive member used was an organic photosensitive member having a diameter of 62 mm, and the closest distance between the developer carrier and the photosensitive member was 3 mm.
It was set to 00 μm.

A roller charger is used as a primary charger, a laser beam is used as an exposure means, and 600 dpi.
Formed a latent image. A roller charger was used as the transfer charger.

[0146] A blade cleaning device was used as a cleaning device for removing the developer remaining on the photoreceptor in the transfer step, and a urethane blade was used as the cleaning blade.

The potential of the latent image on the photoreceptor is dark potential: -5.
The voltage was set so as to be 00 V and the bright portion potential was -150 V.

The photosensitive member was rotated at 117 m / s. The developer carrier was rotated at 161 m / s. DC voltage: -500 V, AC voltage: 1600 V (peak-to-peak), AC frequency: 2
A 300 Hz rectangular wave was applied.

[Evaluation of Negative Sleeve Ghost] Using the above-described developing device as a developing device, there is a solid black image on a block corresponding to one round of the developer carrier as shown in FIG. Was printed, and the evaluation was made based on the image density difference of the negative sleeve ghost at that time. Specifically, it is a value obtained by subtracting the image density of the area A from the image density of the area B in FIG. Table 3 shows the evaluation results. The image density was measured with a Macbeth reflection densitometer.

Further, 5000 images were printed, and the image density of the solid black image and the fog on the photosensitive member were measured. The fog on the photoreceptor was evaluated by tapping off the transfer residual toner on the solid white photoreceptor with a Mylar tape, and subtracting the reflection density of the tape only from the reflection density of the tape on the paper. . The fog was measured using a reflection densitometer (TOKYO DENSHOKU CO., LTD.
REFLECOMETER ODEL TC-
6DS) (reflection density worst value after printing D)
s minus reflection density average value before printing Dr; D
s-Dr).

[Measurement of Amount of Friction Charge of Toner] The amount of friction charge of the toner is determined by a suction Faraday cage method.

The suction-type Faraday cage method is a method of sucking and collecting all the toner in a fixed area on a developing sleeve of a copying machine or a printer using a toner collecting device, and measuring the weight and charge amount of the collected toner. In this method, a charge amount per unit weight of the toner, that is, a triboelectric charge amount (mC / kg) is obtained from the weight and the charge amount of the toner.

The toner collecting device used in the suction type Faraday cage method has a suction device for sucking toner together with air and a collecting device connected to the suction device for collecting toner. The collecting device includes an outer cylinder having a suction port having a tip having a curvature corresponding to the outer peripheral curvature of the developing sleeve for sucking the toner on the developing sleeve, and an inner cylinder having a cylindrical filter paper for collecting the sucked toner. And a cylinder.

In order to specifically perform the suction and recovery of the toner on the developing sleeve by using the toner collecting device, the rotation of the developing sleeve is stopped, and the toner on the developing sleeve is developed by using the suction device. From one end to the other end of the sleeve, suction is performed while pressing the suction port of the suction device against the surface of the developing sleeve along the longitudinal direction, and the suctioned toner is collected by the cylindrical filter paper of the collection device.

The weight W of the cylindrical filter paper from which the toner was recovered
₂ (g) is measured, and the value obtained by subtracting the weight W ₁ (g) of the cylindrical filter paper before recovery from the weight of the cylindrical filter paper after recovery is defined as the weight W ₂ −W ₁ (g) of the recovered toner. At this time, an electrometer (Model 6 manufactured by KEITKEY) was added to the collection device.
17 type), and the charge amount E (μC) of the toner collected on the inner cylindrical filter paper electrostatically shielded from the outside.
Is measured, and the triboelectric charge amount Qm of the toner is calculated based on the following equation.
(MC / kg). Qm = E / (W ₂ −W ₁ )

<Example 1> The toner ghost was evaluated in accordance with the above method using the toner 1 and the developer carrying member a, and the image density difference was 0.01%.
Met. Further, when 5000 sheets were further imaged, the solid black image density was 1.56, the fog on the photosensitive member was 8.0, and the charge amount of the toner on the developer carrying member was -9.9 mC / kg. Table 5 shows the results.

<Example 2> The toner 2 was used as the toner, and the evaluation was performed according to the above method using the developer carrying member a. Table 5 shows the results.

<Embodiment 3> The toner 3 was used as the toner, and the evaluation was performed according to the above method using the developer carrying member a. Table 5 shows the results.

Example 4 Evaluation was performed according to the above-described method using the toner 5 and the developer carrier b as the toner. Table 5 shows the results.

<Example 5> The toner 6 was used as the toner, and the evaluation was performed according to the above method using the developer carrying member b. Table 5 shows the results.

Example 6 Evaluation was performed according to the above-described method using the toner 7 and the developer carrying member a as the toner. Table 5 shows the results.

<Example 7> The toner 8 was used as the toner, and the evaluation was performed according to the above method using the developer carrying member b. Table 5 shows the results.

<Comparative Example 1> The toner 1 was used as the toner, and the evaluation was performed according to the above method using the developer carrying member c. Table 5 shows the results.

<Comparative Example 2> The toner 4 was used as the toner, and the evaluation was performed according to the above method using the developer carrying member c. Table 5 shows the results.

<Comparative Example 3> The toner 9 was used as the toner, and the evaluation was performed according to the above method using the developer carrying member b. Table 5 shows the results.

<Comparative Example 4> Evaluation was performed according to the above-described method using the toner 10 and the developer carrier d as the toner. Table 5 shows the results.

<Comparative Example 5> The toner 11 was used as the toner, and the evaluation was performed according to the above method using the developer carrying member e. Table 5 shows the results.

Comparative Example 6 Evaluation was performed in the same manner as in Example 1 except that the developer carrier was rotated at 100 m / s. Table 5 shows the results.

[0169]

[Table 2]

[0170]

[Table 3]

[0171]

[Table 4]

[0172]

[Table 5]

[0173]

According to the present invention, by improving the toner and the developer carrying member, the durability and the negative sleeve ghost can be suppressed.

In particular, the negative sleeve ghost can be further suppressed by the resin fine particles having a prescribed particle size and particle size distribution contained in the toner.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus capable of performing an image forming method of the present invention.

FIG. 2 is a diagram illustrating an example of a processing apparatus system.

FIG. 3 is a schematic sectional view of the surface treatment apparatus in FIG. 2;

FIG. 4 is a diagram showing an example of a mechanical pulverizer.

FIG. 5 is an explanatory diagram of a sleeve ghost evaluation method.

FIG. 6 is a schematic explanatory view of a measuring device for measuring the charging polarity of resin fine particles.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical casing 4 Pulley 10 Discharge port 15 Vibration feeder 19 Valve 20 Cyclone 21, 23, 26 Valve 22 Bag filter 24 Blower 28 Discharge valve control device 40 Quantitative feeder 59 Discharge on-off valve 60 Discharge port 62 Rotating disk 63 Circulation circuit 64 Raw material hopper 68 Impact chamber 77 Jacket 110 Liner 111 Input port 113 Processing area 114 Rotor 115 Rotor shaft 121 Blade 151 Developing device 153 Photoconductor drum 156 Developing sleeve 158 Elastic blade 163 Toner 171 Fixing roller 172 Pressure roller

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 9/08 371 (72) Inventor Kasugani Rare 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Satoshi Yoshida 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 2H005 AA08 AA15 AB09 CA15 CB07 CB13 DA02 DA03 EA05 EA07 2H077 AD02 AD06 AE03 EA14

Claims (26)

[Claims] 1. A negatively chargeable toner is carried on a surface of a developer carrying member, and is transported to a developing region formed by an electrostatic latent image carrying member and a developer carrying member. In a developing method of forming a toner image by developing an electrostatic latent image carried on the electrostatic latent image carrier with a negatively charged toner carried on a body surface, the developer carrier may be a substrate And a coating layer for coating the surface of the substrate, the coating layer comprising: (i) a solid lubricant, a conductive agent, or a mixture of a solid lubricant and a conductive agent, and (ii) a number average particle size of 0. .3-30 μm spherical particles, and (ii)
i) containing at least a resin, wherein the moving speed of the surface of the developer carrier in the developing region is 1.05 to 2.0 with respect to the moving speed of the surface of the electrostatic latent image carrier.
The negatively chargeable toner has toner particles, inorganic fine powder and resin fine particles containing at least a binder resin and a colorant, and the toner particles are measured by a flow type particle image measuring device. In the number-based particle size distribution based on the equivalent circle diameter of the particles to be obtained, the content of particles having an equivalent circle diameter of 0.60 μm or more and less than 1.00 μm is less than 5.0% by number, and the average equivalent circle diameter is 4%.
And the resin fine particles have a number average particle size of 0.05 to 2.00.
μm. 2. The moving speed of the surface of the developer carrier in the developing area is smaller than the moving speed of the surface of the electrostatic latent image carrier.
2. The ratio is 1.20 to 2.00.
The developing method described in 1. above. 3. The resin fine particles have a number average particle size of 0.1.
The developing method according to claim 1, wherein the thickness is 0 to 1.00 μm. 4. The toner according to claim 1, wherein the negatively chargeable toner is
0.01 to 0.50 parts by weight of the resin fine particles with respect to 0 parts by weight.
The developing method according to any one of claims 1 to 3, wherein the developing method comprises parts by weight. 5. The developing method according to claim 1, wherein the fine resin particles have a positive charging property. 6. The developing method according to claim 1, wherein the resin fine particles are formed of a melamine formaldehyde resin or a benzoguanamine-formaldehyde resin. 7. The toner according to claim 1, wherein the toner particles are produced through a step of removing particles having a circle-equivalent diameter of less than 1.00 μm in a production process. Development method. 8. The developing method according to claim 7, wherein the step of removing the toner particles having an equivalent circle diameter of less than 1.00 μm is a process of applying a mechanical impact force. 9. The toner according to claim 1, wherein the circularity distribution calculated by the following equation is 0. 0 in the number-based circularity distribution of particles having an equivalent circle diameter of 3.00 μm or more measured by a flow type particle image measuring apparatus. 9. The method according to claim 1, wherein the content of particles having a particle size of 90 or more is 90% by number or more, and the content of particles having a circularity a of 0.98 or more is less than 30% by number. The developing method described in 1. above. Circularity a = L ₀ / L (L ₀ ; perimeter of a circle having the same projected area as the particle image, L;
Perimeter of particle image) 10. The developing method according to claim 1, wherein said coating layer contains at least graphite as said solid lubricant. 11. The developing method according to claim 1, wherein the coating layer contains at least carbon black as the conductive agent. 12. The developing method according to claim 1, wherein the coating layer contains at least spherical resin particles as the spherical particles. 13. The developing method according to claim 1, wherein said coating layer contains at least conductive spherical particles as said spherical particles. 14. An electrostatic latent image forming step of forming an electrostatic latent image on the surface of an electrostatic latent image carrier, and a developing step of developing the electrostatic latent image by a developing unit to form a toner image. An image forming method, wherein the developing means carries the negatively chargeable toner on the surface of the developer carrier, and transports the toner to a developing area formed by the electrostatic latent image carrier and the developer carrier; A negatively chargeable toner carried on the surface of the developer carrying member in the developing region develops an electrostatic latent image carried on the latent electrostatic image carrying member to form a toner image, The developer carrier has a substrate and a coating layer that covers the surface of the substrate, the coating layer comprising: (i) a solid lubricant, a conductive agent, or a mixture of a solid lubricant and a conductive agent; (Ii) spherical particles having a number average particle diameter of 0.3 to 30 μm, and (ii)
i) containing at least a resin, wherein the moving speed of the surface of the developer carrier in the developing region is 1.05 to 2.0 with respect to the moving speed of the surface of the electrostatic latent image carrier.
The negatively chargeable toner has toner particles, inorganic fine powder and resin fine particles containing at least a binder resin and a colorant, and the toner particles are measured by a flow type particle image measuring device. In the number-based particle size distribution based on the equivalent circle diameter of the particles to be obtained, the content of particles having an equivalent circle diameter of 0.60 μm or more and less than 1.00 μm is less than 5.0% by number, and the average equivalent circle diameter is 4%.
And the resin fine particles have a number average particle size of 0.05 to 2.00.
μm. 15. The moving speed of the surface of the developer carrier in the developing area is smaller than the moving speed of the surface of the electrostatic latent image carrier.
2. The ratio is 1.20 to 2.00.
5. The image forming method according to item 4. 16. The resin fine particles have a number average particle diameter of 0.1.
2. The structure according to claim 1, wherein the thickness is 10 to 1.00 μm.
16. The image forming method according to 4 or 15. 17. The toner according to claim 17, wherein the negatively chargeable toner is
0.01 to 0.5 parts by weight of the resin fine particles per 100 parts by weight.
17. The image forming method according to claim 14, wherein the content is 0 part by weight. 18. The image forming method according to claim 14, wherein the fine resin particles have a positive charging property. 19. The image forming method according to claim 14, wherein the resin fine particles are formed of a melamine formaldehyde resin or a benzoguanamine-formaldehyde resin. 20. The toner according to claim 14, wherein the toner particles are produced through a step of removing particles having a circle-equivalent diameter of less than 1.00 μm in a production process. Image forming method. 21. The circle-equivalent diameter of the toner particles is 1.00 μm.
21. The image forming method according to claim 20, wherein the step of removing the particles having a particle size of less than a predetermined value is a process of applying a mechanical impact force. 22. In the toner particles, the circularity a calculated by the following equation in the number-based circularity distribution of particles having an equivalent circle diameter of 3.00 μm or more measured by a flow type particle image measuring device is equal to 0. The content of particles having a particle size of 90 or more is 90% by number or more, and the content of particles having a circularity a of 0.98 or more is less than 30% by number. 2. The image forming method according to 1., Circularity a = L ₀ / L (L ₀ ; perimeter of a circle having the same projected area as the particle image, L;
Perimeter of particle image) 23. The image forming method according to claim 14, wherein the coating layer contains at least graphite as the solid lubricant. 24. The image forming method according to claim 14, wherein the coating layer contains at least carbon black as the conductive agent. 25. The image forming method according to claim 14, wherein the coating layer contains at least spherical resin particles as the spherical particles. 26. The image forming method according to claim 14, wherein the coating layer contains at least conductive spherical particles as the spherical particles.