JP3245034B2 - Developer carrier and developing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member or an electrostatic recording dielectric in an image forming apparatus such as a copying machine, a laser beam printer (LBP), an LED printer, a reader printer, a facsimile, and an image display device. The present invention relates to a developing device used for developing and visualizing a latent image such as an electrostatic latent image or a potential latent image formed on a latent image holding surface of a latent image carrier such as the above, and a developer carrier thereof.

More specifically, a powdery dry developer is supplied to and carried on a developer carrying member, and the carried developer is regulated to a thin layer by a layer thickness regulating member to hold the latent image on the latent image carrying member. 1. Field of the Invention The present invention relates to a developing device that transports a latent image to a developing unit facing a surface and develops the latent image, and a developer carrier thereof.

[0003]

2. Description of the Related Art Conventionally, for example, a developing device that develops an electrostatic latent image formed on the surface of a photosensitive drum as a latent image carrier using a magnetic toner of a one-component developer has a problem that toner particles have not been developed. Of the electrostatic latent image on the photosensitive drum with respect to the development reference potential to the magnetic toner particles due to the friction of the toner and the friction between the developing sleeve as a developer carrier and the magnetic toner particles. While the toner is applied very thinly on the developing sleeve by the regulating member to form a thin toner layer, the photosensitive drum and the developing sleeve are conveyed to the developing section opposed to the developing section, where the toner is set in the developing sleeve. The toner flies on the surface of the photosensitive drum and is developed by the action of the magnetic toner due to the magnetic field of the magnet and the developing bias applied to the developing sleeve, and the electrostatic latent image is converted into a toner image. Which visualizes is known.

FIG. 5 shows an example of the configuration of the conventional developing device. In FIG. 5, reference numeral 3 denotes a hopper containing a magnetic toner 4 of a one-component developer, and a developing sleeve 8 is rotatably mounted in the direction of arrow A in an opening of the hopper 3 facing the photosensitive drum 1. Inside the magnet 8, a magnet 5 for magnetically attracting and holding the toner 4 on the developing sleeve 8 is non-rotatably arranged. Further, a stirring blade 10 for stirring and transporting the toner 4 toward the developing sleeve 8 is provided in the hopper 3, and a layer thickness of the toner 4 on the developing sleeve 8 is provided above the opening of the hopper 3. Is regulated at a predetermined interval from the developing sleeve 8. A bias power supply 9 is connected to the developing sleeve 8.

The developing sleeve 8 used in these methods
For example, a metal or an alloy thereof is formed into a cylindrical shape, and the surface thereof is processed to a predetermined surface roughness by electrolysis, blast, file, or the like. But,
In this case, of the toner layer formed on the surface of the developing sleeve 8 by the regulating blade 2, the toner near the developing sleeve surface has a very high excess charge,
Since the toner is strongly attracted to the surface of the developing sleeve by the reflection force, and there is no chance of friction between the toner and the developing sleeve, the toner cannot obtain a suitable charge. In such a situation, sufficient development and transfer are not performed, and the resulting image has a large amount of uneven density and scattered characters.

In order to prevent the generation of such an excessively charged toner and the strong adhesion of the toner, for example, JP-A-1-277264 and JP-A-3-36570.
As disclosed in Japanese Unexamined Patent Publication, it has been proposed that a resin film layer composed of a resin, conductive fine powder, a solid lubricant and the like be formed on the surface of a developing sleeve and used for a developing device. Furthermore, in order to ensure the stability of toner transportability with long-term use and to stabilize the roughness of the developing sleeve surface, spherical particles are contained in the resin coating layer as disclosed in JP-A-3-200986. Proposals for addition have been made.

However, in recent years, there has been a further demand for a reduction in the energy consumption of the LBP body and the copying machine. In order to reduce the energy required for fixing, studies on low-temperature fixing of toner have been advanced. Therefore, as typified by surf fixing and the like, it is required to melt the toner in a shorter time and at a lower temperature. For this reason, the binder resin of the toner tends to be reduced in molecular weight, and there is a concern that the toner may be fused to the surface of the developing sleeve. Further, in order to improve the image quality of electrophotography, the particle size of the toner has been reduced, and accordingly, the above-mentioned toner tends to adhere firmly to the surface of the developing sleeve. Easily contaminated by

Further, the developing device is formed into a cartridge or a unit. However, the durability of the developing cartridge and the developing unit is further improved so that a high-quality image can be stably provided for a long period of time. It is required to be.

[0009]

Conventionally, for example, the number of durable sheets required for a developing sleeve used for a developing cartridge has been about 2,000 to 8,000 sheets because the developing cartridge is small and lightweight. However, in recent years, it has become necessary to extend the life of the developing sleeve in response to an increase in the capacity of the cartridge and a toner supply method.
Also, in order to improve the image quality, there is a tendency that the regulation of the toner is strengthened and the toner layer on the developing sleeve is made thinner.
The physical load on the toner and the developing sleeve has been increasing.

For example, the technique described in the above-mentioned Japanese Patent Application Laid-Open No. 1-277265 is effective for a conventional cartridge having a low durability. However, graphite added to the resin coating layer causes irregularities to be formed on the surface of the resin coating layer, so a relatively large amount of addition is required, and the resin coating layer is brittle in terms of strength and is easily smoothed by abrasion. .

On the other hand, in the technique disclosed in Japanese Patent Application Laid-Open No. 3-200986, favorable irregularities are formed on the surface of the resin coating layer by adding a small amount thereof, so that the improvement is maintained in maintaining the irregularities. However, it is not yet sufficient in terms of abrasion and peeling of the added particles in the resin coating layer or toner adhesion.

The present inventors have conducted various studies to prevent the added particles added to the resin film layer on the surface of the developing sleeve from being worn or peeled off, or to prevent toner adhesion. It has been found that spherical resin particles obtained by modifying the above may be used, and the present invention has been completed.

Therefore, an object of the present invention is to stably and appropriately charge the toner on the developer carrying member even when the development is repeated, and to prevent the occurrence of density reduction and ghost even when forming a large number of images. Another object of the present invention is to provide a developer carrying member capable of obtaining a high quality image which is uniform and free from uneven density, fogging and scattering.

Another object of the present invention is to provide a highly durable developer capable of stably obtaining a high-quality image for a long period of time by reducing toner adhesion to a resin coating layer coated on the surface. The purpose is to provide a carrier.

Still another object of the present invention is to provide a developer carrier having further improved durability by further improving the abrasion resistance of the resin coating layer.

Still another object of the present invention is to provide a developing device having a developer carrier having a uniform surface state over a long period of time and capable of stably obtaining a high quality image. is there.

[0017]

The above object is achieved by a developer carrier and a developing device according to the present invention. In summary, the present invention relates to a developer carrier that carries a developer and conveys the developer to a developing unit facing the latent image carrier, and uses the developer to develop a latent image formed on the latent image carrier. The developer carrier is formed by forming a resin coating layer containing spherical resin particles on the surface of a metal cylinder, and the spherical resin particles containing the resin particles adhere to the surface with fine resin particles. The surface of the resin particles having the fine particle size, silicone resin, fluororesin, polyethylene, polyethersulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane,
A developer carrier formed of a styrene-based resin or an acrylic-based resin.

According to another aspect of the present invention, while a developer is carried on a developer carrying member and a thin layer of the developer is formed by a developer layer regulating member, the developer is carried by the developer carrying member to form a latent image. In a developing device that transports the developer to a developing unit facing the carrier and uses the developer to develop a latent image formed on the latent image carrier,
The developer carrier has a resin coating layer containing spherical resin particles whose surface is modified by fine particle resin particles, formed on the surface of a metal cylinder, and the fine particle resin particles are ,
The developing device is formed of silicon resin, fluororesin, polyethylene, polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane, styrene resin, or acrylic resin.

Preferably, the spherical resin particles have a particle diameter of 0.3.
The resin particles having a number average particle diameter of about 30 μm and a fine particle diameter have a particle diameter ratio of 0.2 or less to the spherical resin particles. Further, the resin coating layer may contain a conductive fine powder, and may further contain a lubricating substance.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the developing device of the present invention. In FIG. 1, reference numeral 1 denotes an image carrier for carrying an electrostatic latent image formed by a known process, for example, an electrophotographic photosensitive drum. Used to develop latent images.

The developing device includes a hopper 3 containing a magnetic toner 4 of a one-component developer, and a developing sleeve 8 as a developer carrying member is provided in an opening facing the photosensitive drum 1.
Is installed rotatably. The developing sleeve 8 is formed by forming a resin coating layer 7 on the surface of a sleeve base 6 which is a metal or alloy cylindrical tube, and according to the present invention, the resin coating layer 7 has fine resin particles on the surface. Contains spherical resin particles whose surface has been modified by fixing them. The resin coating layer 7 will be described later.

In the developing sleeve 8, a magnet 5 for magnetically attracting and holding the magnetic toner 4 on the developing sleeve 8 is non-rotatably arranged. In the hopper 3,
A stirring blade 10 for stirring and transporting the magnetic toner 4 is provided.

The developing sleeve 8 carries the magnetic toner 4 supplied by the stirring blade 10 and rotates in the direction of arrow A to convey the toner 4 to the developing section where the developing sleeve 8 and the photosensitive drum 1 face each other. I do. In the transport process, the toner 4 acquires a triboelectric charge that can develop the electrostatic latent image on the photosensitive drum 1 by friction with the developing sleeve 8.

In order to regulate the thickness of the magnetic toner 4 conveyed to the developing section, the hopper 3 on which the developing sleeve 8 is disposed
A regulating blade 2 made of ferromagnetic metal is provided above the opening
Is installed. The regulating blade 2 is suspended from the hopper 3 as desired on the surface of the developing sleeve 8, and is positioned with a gap of about 50 to 500 μm from the surface of the developing sleeve 8. The magnetic toner 4 on the developing sleeve 8 has a line of magnetic force from the magnetic pole N <b> 1 of the magnet 5.
As a result, a thin layer of the magnetic toner 4 is formed on the developing sleeve 8. A non-magnetic blade may be used as the regulating blade 2.

The thickness of the thin layer of the magnetic toner 4 formed on the developing sleeve 8 is preferably smaller than the minimum gap between the developing sleeve 8 and the photosensitive drum 1 in the developing section. The present invention is particularly effective for a developing device of a type that develops an electrostatic latent image with such a thin toner layer, that is, a non-contact type developing device. However, the present invention can also be applied to a developing device in which the thickness of the toner layer in the developing section is equal to or greater than the minimum gap between the developing sleeve 8 and the photosensitive drum 1, that is, a contact-type developing device.

Hereinafter, in order to avoid the complexity of the description, a non-contact type developing device will be further described as an example. A developing bias voltage is applied to the developing sleeve 8 by a bias power supply 9 in order to cause the magnetic toner 4 carried on the developing sleeve 8 to fly in the developing section. When a direct voltage is used as the developing bias voltage, a voltage having a value between the potential of the image portion of the electrostatic latent image (the region where the magnetic toner 4 is adhered and visualized) and the potential of the background portion is used. Preferably, it is applied to the sleeve 8. On the other hand, in order to increase the density of the developed image or improve the gradation, an alternating voltage may be applied to the developing sleeve 8 to form an oscillating electric field in which the direction is alternately reversed in the developing unit. In this case, it is preferable to apply to the developing sleeve 8 an alternating bias voltage on which a DC voltage component having a value between the potential of the image portion and the potential of the background portion is superimposed.

In so-called regular development in which toner is adhered to a high potential portion of an electrostatic latent image having a high potential portion and a low potential portion to visualize the toner, a toner charged to a polarity opposite to the polarity of the electrostatic latent image is used. On the other hand, in so-called reversal development, in which toner is attached to a low potential portion of an electrostatic latent image to visualize the toner, a toner charged to the same polarity as the polarity of the electrostatic latent image is used. In addition,
High potential and low potential are expressed by absolute values.
In any case, the magnetic toner 4 is charged to a polarity for developing the electrostatic latent image by friction with the developing sleeve 8.

According to the present invention, as described above, the spherical resin particles whose surface is modified by adhering fine resin particles to the surface of the sleeve base 6 made of a metal (including alloy) cylindrical tube. Forming a resin coating layer 7 containing
Is composed. FIG. 2 shows a cross section of the surface of the developing sleeve 8 of the present invention. As shown in FIG. 2, the developing sleeve 8 has a resin coating layer 7 formed on the surface of a base 6, and the resin coating layer 7 is formed by forming spherical resin particles 13 having fine resin particles 14 fixed on the surface. 12 are dispersed.

As the resin (binder resin) 12 used for forming the resin coating layer 7, a generally known resin can be used. For example, styrene resin, vinyl resin, polyether sulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, fluorine resin,
Thermoplastic or photo-curable resins such as cellulose resin, acrylic resin, etc., epoxy resin, polyester resin, alkyd resin, phenol resin, melamine resin, polyurethane resin, urea resin, silicone resin, polyimide resin, etc. Can be used. Above all, silicone resin, fluororesin, or mechanical properties such as polyethersulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane, styrene resin, and acrylic resin Superior ones are more preferred.

The resin used for the spherical resin particles 13 includes
The resin 12 can be appropriately selected from known resins by considering the resin 12 used for forming the resin coating layer 7 and the dispersion stability with the dispersion solvent used for forming the coating layer 7.

Examples of the resin used for the spherical resin particles include acrylic resin particles such as polyacrylate and polymethacrylate, depolyamide resin particles such as nylon 6, polyurethane resin particles such as polyethylene and polypropylene, and silicone resin. Particles, phenolic resin particles, polyurethane resin particles, styrene resin particles, benzoguanamine particles, and the like.

The spherical resin particles can be obtained by thermally or physically spheroidizing the resin particles obtained by the pulverization method,
It can be produced by directly spheroidizing by a suspension polymerization method or the like. The particle diameter of the spherical resin particles is preferably 0.3 to 30 μm in number average particle diameter, more preferably 1 to 2 μm.
5 μm.

According to the present invention, the adhesion of the toner to the surface of the developing sleeve 8 having the resin coating layer 7 formed thereon is reduced, and
In order to improve the abrasion resistance of the resin coating layer 7, the surface is modified by fixing surface-modified particles 14 having a fine particle diameter to the surface of the spherical resin particles 13 contained in the resin coating layer 7.

The particle size of the surface-modified particles 14 is such that the ratio of the particle size to the spherical resin particles 13, that is, (the particle size of the surface-modified particles 14 / the particle size of the spherical resin particles 13) is 0.2 or less. Is preferred. Surface-modified particles 14 composed of fine resin particles having a finer particle diameter having higher wear strength than spherical resin particles 13 or surface modified particles 14 composed of fine resin particles having a low surface energy.
Thus, by covering a part or all of the surface of the spherical resin particles 13, the surface of the spherical resin particles 13 can be modified to prevent abrasion of the surface of the spherical resin particles 13 and further reduce adhesion of toner. it can. Therefore, the developing sleeve 8 in which the resin coating layer 7 containing the surface-modified spherical resin particles 13 is formed on the surface reduces the adhesion of the toner to the surface and improves the wear resistance of the resin coating layer 7. be able to.

The resin used for the surface-modified particles 14 is as follows.
Although generally known resins can be used, for example, those having low surface energy such as silicone resin, fluororesin and polyethylene are particularly preferable because of their large surface modification effect. Further, those excellent in mechanical properties such as polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane, styrene resin, and acrylic resin are also preferable. From the viewpoint of good charge-providing properties, phenol, acrylic, silicon, fluorine, nylon and other N-containing resins are preferred.

Specifically, considering the adhesion between the spherical resin particles 13 and the resin 12 for forming the resin coating layer 7 and the chargeability with the toner and the difficulty in fusing, the resin is appropriately selected from the above resins. It is better to select and use.

The surface modification of the spherical resin particles 13
A method of externally adding resin powder of the surface-modified particles 14 to the surface of the particles 13 by heat treatment or mechanical impact, and fixing and covering the surface or a part of the surface of the particles 13;
The surface of the particles 13 is covered with the resin solution of No. 4, dried and cured to fix the surface-modified particles 14 to the surfaces of the particles 13.

According to the present invention, a conductive agent can be further added to the resin coating layer 7. Examples of the conductive agent to be added to the resin coating layer 7 include conductive carbon black, metal powders such as aluminum, copper, nickel, and silver; antimony oxide;
Conductive metal oxides such as indium oxide, titanium oxide, tin oxide, and aluminum oxide, short metal fibers, carbon fibers, and the like can be used. The volume resistance value of the resin coating layer 7 is preferably 10 ³ Ωcm or less, and the amount of the conductive agent added is adjusted so as to obtain this volume resistance value. In the present invention, the measurement of the volume resistance of the resin coating layer 7 is performed using Loresta SP.
MCP-T500 (Mitsubishi Yuka) was used.

The resin coating layer 7 can further contain a solid lubricant. For example, graphite, molybdenum disulfide, boron nitride, zinc stearate and the like are added in an amount of 0.1 to 400% with respect to the resin.
Preferably it is about 1 to 200%.

In the present invention, the surface roughness of the developing sleeve 8 is 0.5 (arithmetic average roughness Ra (JIS B0601)).
To 5 μm, more preferably 1 to 3.5 μm.
The measurement of surface roughness Ra is performed by SE-3300 (Kosaka Laboratory)
, Using a feed speed of 0.5 mm / sec and a measurement length of 4.
0 mm, roughness cutoff λc = 0.8, and auto leveling on.

The toner of the one-component developer used in the present invention will be described.

The toner is roughly classified into a dry toner and a wet toner. However, the dry toner is mainly used at present because the problem of solvent evaporation is large. Toner is mainly melted and kneaded with resin, release agent, charge control agent, colorant, etc.
It is a fine powder that has been crushed after being individualized, and then classified and the like to have a uniform particle size distribution. As the binder resin used for the toner, generally known resins can be used.

For example, homopolymers of styrene such as styrene, α-methylstyrene, p-chlorostyrene and the like, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-ethyl acrylate copolymer Coalesce, styrene-butyl acrylate copolymer,
Styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethyl methacrylate Aminoethyl copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene-maleic acid Styrene-based copolymers such as ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene polyvinyl butyral, polyacrylic resin, rosin, modified rosin, tempel resin,
Phenol resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, paraffin wax, carnauba wax and the like can be used alone or in combination.

A pigment can be contained in the toner. For example, carbon black, nigrosine dye, lamp black, Sudan black SM, Fast Yellow G, Benzidine Yellow, Pigment Yellow, India First Orange, Irgazine Red, Paranitroaniline Red, Toluidine Red, Carmine FB, Permanent Bordeaux FRR, Pigment
Orange R, Risor Red 2G, Lake Red C, Rhodamine FB, Rhodamine B Lake, Methyl Violet B Lake, Phthalocyanine Blue, Pigment Blue, Brilliant Green B, Phthalocyanine Green, Oil Yellow GG, Pomelo First Yellow CGG, Kaya set Y963, Kaya set Y
G, Pomelo First Orange RR, Oil Scarlet, Orazol Brown B, Pomelo First Scarlet CG, Oil Pink OP and the like can be applied.

In order to use the toner as a magnetic toner,
A magnetic powder may be contained in the toner. As such magnetic powder, a substance that is magnetized in a magnetic field is used, and powder of a ferromagnetic metal such as iron, cobalt, and nickel;
Alternatively, there are alloys and compounds such as magnetite, hematite, and ferrite. The content of the magnetic powder is preferably 15 to 79% by weight based on the weight of the toner.

Various releasing agents may be added to the toner. Examples of such releasing agents include polyfluoroethylene, fluororesin, fluorocarbon oil, silicone oil, low molecular weight polyethylene, low molecular weight polypropylene, Various waxes and the like can be mentioned. Further, if necessary, a charge control agent for facilitating positive or negative charge may be added.

FIG. 3 is a block diagram showing another embodiment of the developing device of the present invention. In this developing device, the developing sleeve 8
An elastic plate 11 made of a material having rubber elasticity such as urethane rubber or silicone rubber or a material having metal elasticity such as phosphor bronze or stainless steel is used as a member for regulating the layer thickness of the magnetic toner 4 above. It is characterized in that the elastic plate 11 is pressed against the developing sleeve 8 in a posture opposite to the rotation direction. 3, the same reference numerals as those shown in FIG. 1 indicate the same members.

In such a developing device, the developing sleeve 8
A thinner toner layer can be formed thereon. Also in this embodiment, the developing sleeve 8 is a spherical resin particle having a surface modified by fixing fine resin particles on the surface of a sleeve base 6 made of a metal (including alloy) cylindrical tube. Is formed by forming a resin coating layer 7 containing

FIG. 4 is a structural view showing still another embodiment of the developing device of the present invention. In this developing device, the elastic plate 11 for regulating the layer thickness of the magnetic toner 4 on the developing sleeve 8 is used.
3 is different from the developing device of FIG. 3 in that it is pressed against the developing sleeve 8 in a posture opposite to the rotation direction.

Also with this developing device, a thinner toner layer can be formed on the developing sleeve 8 as in the developing device of FIG. Similarly, the developing sleeve 8 contains spherical resin particles whose surface has been modified by fixing fine resin particles to the surface on the surface of a sleeve base 6 made of a metal (including alloy) cylindrical tube. It is formed by forming a resin coating layer 7.

In the developing device shown in FIGS. 3 and 4, since a thin toner layer can be formed on the developing sleeve 8 by the elastic plate 11, even if a magnetic toner of a one-component developer is used as the toner 4, It is also suitable when using a non-magnetic toner as a component developer.

Hereinafter, the present invention will be described in more detail by way of specific examples, but the present invention is not limited thereto.

Example 1 As the spherical resin particles 13 to be mixed with the resin coating layer 7 on the surface of the developing sleeve 8, the number average diameter D1 cross-linked by a cross-linking agent was used.
= 12.5 μm polymethyl methacrylate (PMMA)
Particles were used. The PMMA particles are produced by a suspension method and have a spherical form. Teflon fine powder was used as the surface-modified particles 14.

The jacket of a 75-liter Henschel mixer was heated with hot water, 300 g of Teflon fine powder was added to 10 kg of PMMA particles, and the mixture was stirred at an ambient temperature of 90 ° C. to adhere the fine Teflon powder to the surface of the PMMA particles. The surface was modified. The surface-modified PMMA particles with the fine Teflon powder are analyzed by an electron microscope (FE-SEM).
As a result, the surface of the PMMA particles was sufficiently covered with the Teflon particles.

Next, a coating liquid for a resin coating layer was prepared according to the following mixing ratio.

Phenol resin intermediate 100 parts by weight Surface-modified PMMA particles 15 parts by weight Conductive tin oxide 9 parts by weight Conductive carbon black 11 parts by weight Methanol 60 parts by weight 240 parts by weight isopropyl alcohol

The above-mentioned raw materials were dispersed by a sand mill using glass beads to prepare a coating liquid. First, after a methanol solution of a phenol resin intermediate is diluted with isopropyl alcohol, surface-modified PPM particles are added and dispersed. After preparing the coating solution, separate from the glass beads,
The viscosity of the coating solution measured at room temperature was 54.8 m.
Pa · s.

This coating solution was applied to a developing sleeve substrate. The developing sleeve base is an aluminum cylindrical tube having an outer diameter of 20 mm. The cylindrical tube was set up and rotated, and the coating liquid was applied to a uniform film thickness while the spray gun was lowered at a constant speed. Thereafter, the coating film was dried and hardened in a drying furnace to obtain a developing sleeve having a resin coating layer containing surface-modified PMMA particles on the surface. The surface roughness of this developing sleeve was measured to be 1.53 μm in Ra notation.
m.

Further, an OHP sheet was wrapped around another identical cylindrical tube, and a coating solution was applied in the same manner to obtain a sample for measuring volume resistance. Measurement is Loresta MCP-T500 (Mitsubishi Yuka)
This was performed using Its volume resistance was 7.35 Ωcm.

The above spherical resin particles 13 and surface modified particles 1
Table 1 shows the four types, the surface roughness of the developing sleeve, and the like. In Table 1, the spherical resin particles are shown as spherical particles, and the surface-modified particles are shown as modified resins.

Next, the above-mentioned developing sleeve was incorporated in a developing device of a copying machine NP-6016 manufactured by Canon Inc., and was used for development to form a solid black image. Image formation at 15 ° C
A durability test of 30,000 sheets was performed in three levels of a low humidity environment of / 10% RH, a normal environment of 23 ° C./60% RH, and a high humidity environment of 32 ° C./85% RH. During that time, toner was supplied to the developing device in such a manner that 100 g of toner was replenished every time 100 g of toner was consumed.

The toner used had the following formulation.

Styrene-butyl acrylate 100 parts by weight Magnetite 51 parts by weight Copy blue 2 parts by weight Low molecular weight polypropylene 7 parts by weight

The above raw materials were mixed by a Henschen mixer, heated and mixed by a twin-screw extruder, cooled, and coarsely ground, finely ground and classified.
A classified toner product having a weight average particle diameter of 8 μm, a particle number distribution of particles having a particle diameter of 4.0 μm or less being 16.3%, and a weight% of particles having a particle diameter of 10.1 μm or more being 0.86%. Obtained. The particle size distribution of the classified toner was measured by attaching a 100 μm aperture to Multisizer II manufactured by Coulter Corporation and measuring 10,000 or more toner particles. 1.1 parts by weight of hydrophobic colloidal silica was externally added to 100 parts by weight of this classified toner product, and used as a toner.

FIG. 6 shows the change in density according to the number of solid black images formed in this embodiment. In FIG. 6, the graph shows a case where the polygonal line is 15 ° C./10%, a case where the polygonal line is 23 ° C./60%, and a case where the polygonal line is 32 ° C./85% (hereinafter, FIGS. 27 is the same). FIG.
As shown in Table 2, in each temperature and humidity environment, the density of the solid black image was slightly reduced due to image formation up to 30,000 sheets.

The surface roughness Ra of the developing sleeve after the durability test on 30,000 sheets of image formation was 1.45 μm. Table 1 shows the result of observing the surface of the developing sleeve after the endurance test by FE-SEM.

In Table 1, the symbols have the following meanings in relation to toner fusion. ◎: No fusion, ○: Almost none, ○
△: slightly, △: slightly bad, △ ×: quite bad,
×: Bad. In the present embodiment, the surface of the resin coating layer on the developing sleeve surface was shaved off, and some of the particles in the coating layer were exposed on the surface. Few were recognized.

[0069]

[Table 1]

Embodiment 2 This embodiment is different from Embodiment 1 in that P
The number average particle diameter D1 of the MMA particles was set to 3.2 μm. For 10 kg of the PMMA particles, Teflon fine powder is 40
0 g was added. Otherwise, the same processing as in Example 1 was performed.
Surface-modified PMMA particles with Teflon fine powder were obtained.

The coating liquid was prepared according to the following compounding ratio. The processing method is the same as in the first embodiment.

Phenol resin intermediate 100 parts by weight Surface-modified PMMA particles 15 parts by weight Conductive tin oxide 12 parts by weight Conductive carbon black 8 parts by weight Methanol 50 parts by weight Isopropyl alcohol 250 parts by weight

The viscosity of the coating solution measured at room temperature was 59.5 mPa · s. Using this coating liquid, coating was performed on an aluminum cylindrical tube having an outer diameter of 20 mm in the same manner as in Example 1, and the surface modification P with fine Teflon powder was used.
A developing sleeve having on its surface a resin coating layer containing MMA particles was obtained. The surface roughness Ra of the developing sleeve is 1.
The volume resistivity was 35 μm and the volume resistance was 9.35 μm.

As in Example 1, an endurance test was performed on 30,000 sheets of image formed. FIG. 7 shows a density change depending on the number of solid black images formed at that time. The density reduction of the solid black image was slight. In each temperature and humidity environment, almost no fusion of the toner to the surface of the developing sleeve was observed. The surface roughness Ra of the developing sleeve after the durability test was 1.28 μm.

Example 3 In this example, as shown in Table 1, PMMA particles having a number average particle diameter D1 = 25.3 μm were used in Example 1. Others were treated in the same manner as in Example 1 to obtain surface-modified PMMA particles using fine Teflon powder.

The coating liquid was prepared according to the following compounding ratio.

100 parts by weight of phenol resin intermediate 7 parts by weight of the above surface-modified PMMA particles 13 parts by weight of conductive tin oxide 7 parts by weight of conductive carbon black 50 parts by weight of methanol 250 parts by weight of isopropyl alcohol

The viscosity of the coating solution measured at room temperature was 50.5 mPa · s. Using this coating liquid, coating was performed on an aluminum cylindrical tube having an outer diameter of 20 mm in the same manner as in Example 1, and the surface modification P with fine Teflon powder was used.
A developing sleeve having on its surface a resin coating layer containing MMA particles was obtained. The surface roughness Ra of the developing sleeve was 2.29 μm, and the volume resistance value was 7.85 μm.

In the same manner as in Example 1, an endurance test was performed for 30,000 sheets of image formed. At that time, the change in density due to the number of solid black images formed was slight as shown in FIG. In each temperature and humidity environment, almost no fusion of the toner to the surface of the developing sleeve was observed. The surface roughness Ra of the developing sleeve after the durability test was 1.83 μm.

Example 4 As shown in Table 1, in place of the PMMA particles of Example 1,
Using spherical styrene particles having a number average particle diameter D1 = 12.8 μm, 10 kg of the styrene particles was subjected to a surface treatment with 300 g of polytrifluorochloroethylene fine powder,
Fine powder of polytrifluorochloroethylene was fixed to the surface of the styrene particles to obtain surface-modified styrene particles with fine powder of polytrifluorochloroethylene.

A coating solution was prepared according to the following compounding ratio. The processing method is the same as in the first embodiment.

100 parts by weight of a phenol resin intermediate 15 parts by weight of the above-mentioned surface-modified styrene particles 30 parts by weight of crystalline graphite (average particle size: 4 μm) 5 parts by weight of conductive carbon black 60 parts by weight of methanol 240 parts by weight of isopropyl alcohol

The viscosity of the coating solution measured at room temperature was 62.9 mPa · s. Using this coating solution, coating was performed on an aluminum cylindrical tube having an outer diameter of 20 mm in the same manner as in Example 1, and a resin coating layer containing surface-modified styrene particles with fine powder of polytrifluorochloroethylene was coated on the surface. Was obtained. The surface roughness Ra of the developing sleeve is 1.73 μm, and the volume resistance value is 5.
It was 75 Ωμm.

In the same manner as in Example 1, an endurance test for forming an image of 30,000 sheets of solid black was performed. FIG. 9 shows a density change according to the number of solid black images formed at that time. The density decrease of the solid black image is slight. The surface roughness Ra of the developing sleeve after the durability test was 1.61 μm. When the surface of the developing sleeve was observed by FE-SEM, the surface of the resin coating layer on the surface of the developing sleeve was shaved, and some of the particles in the resin coating layer were exposed on the surface. However, almost no fusion of the toner to the surface of the developing sleeve was observed in each temperature and humidity environment.

Example 5 In this example, as shown in Table 1, the number average particle diameter D1 of the styrene particles in Example 4 was 25.5 μm.
Except for this, the same treatment as in Example 4 was carried out to obtain surface-modified styrene particles with polytrifluorochloroethylene fine powder.

A coating liquid was prepared according to the following compounding ratio.

Phenol resin intermediate 100 parts by weight Styrene particles 8 parts by weight Crystalline graphite (average particle size 4 μm) 12 parts by weight Conductive carbon black 5 parts by weight Methanol 50 parts by weight Isopropyl alcohol 250 parts by weight

The viscosity of the coating solution measured at room temperature was 57.5 mPa · s. Using this coating solution, coating was performed on an aluminum cylindrical tube having an outer diameter of 20 mm in the same manner as in Example 1, and a resin coating layer containing surface-modified styrene particles with fine powder of polytrifluorochloroethylene was coated on the surface. Was obtained. The surface roughness Ra of the developing sleeve is 2.55 μm, and the volume resistance value is 6.
It was 80 Ωμm.

Similarly, a durability test was performed for 30,000 sheets of image-formed sheets. FIG. 10 shows a density change according to the number of formed solid black images at that time. The density of the solid black image slightly decreased. In each temperature and humidity environment, almost no fusion of the toner to the surface of the developing sleeve was observed.
The surface roughness Ra of the developing sleeve after the durability test is 2.38 μ.
m.

Example 6 In this example, as shown in Table 1, spherical phenol resin particles having a number average particle diameter D1 = 13.3 μm were used as spherical resin particles, and silicone resin powder was used as surface modified particles. .

To 10 kg of the phenol resin particles, 300 g of silicone resin powder was externally added and mixed. Then, in a device equipped with a rotating blade and a fixed liner, the clearance between the blade and the liner was set to 2 mm, and the above-mentioned particle mixture was passed several times by a circulation mechanism while rotating the blade, so that the silicone resin The powder was fixed to obtain surface-modified phenol resin particles with a silicone resin powder.

The coating liquid was prepared according to the following composition.

100 parts by weight of phenolic resin intermediate 13 parts by weight of the above surface-modified phenol particles 9 parts by weight of conductive tin oxide 11 parts by weight of conductive carbon black 5 parts by weight of molybdenum disulfide 5 parts by weight of methanol 60 parts by weight of isopropyl alcohol 240 parts by weight

The viscosity of the coating solution measured at room temperature was 48.5 mPa · s. Using this coating solution, coating was performed on an aluminum cylindrical tube in the same manner as in Example 1 to obtain a developing sleeve having on its surface a resin coating layer containing surface-modified phenol particles of silicone resin powder. The adhesion amount of this resin coating layer was 95 mg / m ² (whether the unit is this ??). A cylindrical tube having an outer diameter of 16 mm was used. The surface roughness Ra of this developing sleeve was 1.83 μm, The volume resistance value was 7.40 Ωμm.

The toner having the following formulation was used. The processing method was the same as in Example 1.

Polyester resin 100 parts by weight Magnetite 82 parts by weight Negative charge control agent 4 parts by weight Low molecular weight polypropylene 3 parts by weight

According to the above formula, the weight average particle size was 6.58.
μm, and the number% of particles having a particle size of 4.0 μm or less is 15.5.
%, Weight% of particles having a particle size of 10.1 μm or more is 0.95%
A classified toner product having a particle size distribution of Hydrophobic colloidal silica was added to 100 parts by weight of the classified toner.
7 parts by weight were externally added and used as a toner.

Next, as an image forming apparatus, a laser jet IV Si manufactured by Hewlett-Packard (HP) EP-
The above-mentioned developing sleeve was processed and attached to the N cartridge. Using the laser jet IV Si, an endurance test for image formation of 30,000 sheets of solid black was performed as in the past.

FIG. 11 shows the density change depending on the number of solid black images formed at that time. As shown in FIG. 11, the density of the solid black image slightly decreased. In each temperature and humidity environment, almost no fusion of the toner to the surface of the developing sleeve was observed. The surface roughness Ra of the developing sleeve after the durability test was 1.75 μm.

Example 7 In this example, the surface-modified phenol resin particles of the silicone resin powder of Example 6 were used.

The coating liquid was prepared according to the following mixing ratio.

Phenol resin intermediate 100 parts by weight Surface-modified phenol particles 13 parts by weight Crystalline graphite (average particle size 4 μm) 14 parts by weight Conductive carbon black 5 parts by weight Methanol 60 parts by weight Isopropyl alcohol 240 parts by weight

The viscosity of the coating solution measured at room temperature was 53.5 mPa · s. Using this coating solution, coating was performed on an aluminum cylindrical tube having an outer diameter of 16 mm to obtain a developing sleeve having on its surface a resin coating layer containing surface-modified phenol particles of silicone resin powder. The adhesion amount of the resin coating layer was 87 mg / m ² . The surface roughness Ra of the developing sleeve was 1.92 μm, and the volume resistance was 6.95 Ωμm.

As in Example 6, the developing sleeve was used for LaserJet IV Si (Hewlett-Packard), and the toner of Example 6 was used to perform an endurance test on image formation of 30,000 sheets of solid black.

FIG. 12 shows the density change according to the number of solid black images formed at that time. The density reduction of the solid black image was slight. In each temperature and humidity environment, almost no fusion of the toner to the surface of the developing sleeve was observed. The surface roughness Ra of the developing sleeve after the durability test was 1.77 μm.

Example 8 In Example 6, spherical styrene resin particles having a number average particle diameter D1 = 20.3 μm were used in place of the spherical phenol resin particles, and nylon fine powder was used in place of the silicone resin fine powder. Otherwise, as in Example 6, 300 g of nylon fine powder was added to 10 kg of styrene resin particles,
By treating in the same manner and fixing to the surface, surface-modified styrene resin particles with fine nylon powder were obtained.

The coating liquid was prepared according to the following composition.

100 parts by weight of a phenol resin intermediate 7 parts by weight of the above-mentioned surface-modified styrene particles 15 parts by weight of crystalline graphite (4 μm average particle size) 4 parts by weight of conductive carbon black 60 parts by weight of methanol 240 parts by weight of isopropyl alcohol

When the viscosity of this coating solution was measured at room temperature, it was 59.5 mPa · s. Using this coating solution, a coating sleeve is formed on an aluminum cylindrical tube having an outer diameter of 16 mm in the same manner as in Example 6, and a developing sleeve having on its surface a resin coating layer containing surface-modified styrene particles of nylon fine powder is blended. I got The amount of the resin coating layer attached is 92 mg / m ^2.
Met. The surface roughness Ra of the developing sleeve is 1.95.
μm, and the volume resistance value was 7.10 Ωcm.

In this example, the toner of Example 6 was used, and an endurance test for image formation of 30,000 sheets of solid black was similarly performed. At that time, the change in density due to the number of solid black images formed was slight as shown in FIG. In each temperature and humidity environment, almost no fusion of the toner to the surface of the developing sleeve was observed. The surface roughness Ra of the developing sleeve after the durability test was 1.72 μm.

Example 9 In Example 8, spherical styrene resin particles having a number average particle diameter D1 = 10.5 μm were used. Otherwise, Example and 8
To obtain surface-modified styrene resin particles with fine nylon powder.

The coating liquid was prepared according to the following composition.

Phenol resin intermediate 100 parts by weight Surface-modified styrene particles 13 parts by weight Conductive carbon black 22 parts by weight Methanol 60 parts by weight Isopropyl alcohol 240 parts by weight

The viscosity of this coating solution measured at room temperature was 42.5 mPa · s. Using this coating solution, a coating sleeve is formed on an aluminum cylindrical tube having an outer diameter of 16 mm in the same manner as in Example 8, and a developing sleeve having on its surface a resin coating layer containing surface-modified styrene particles of fine nylon powder. I got The amount of the resin coating layer attached is 92 mg / m ^2.
The surface roughness Ra of the developing sleeve was 1.65 μm, and the volume resistance value was 5.40 Ωcm.

The toner having the following formulation was used.

Styrene-butyl acrylate-n-butyl maleate half ester copolymer 100 parts by weight Magnetite 80 parts by weight Negative charge control agent 5 parts by weight Low molecular weight polypropylene 5 parts by weight

The above raw materials were mixed by a Henschen mixer, heated and mixed by a twin-screw extruder, cooled, and coarsely ground, finely ground, and classified.
Classification of toner having a weight average particle size of 6.58 μm, a particle number distribution of particles having a particle size of 4.0 μm or less being 17.3%, and a weight% of particles having a particle size of 10.1 μm or more being 1.2%. Product was obtained. 1.1 parts by weight of hydrophobic colloidal silica was externally added to 100 parts by weight of this classified toner product, and used as a toner.

Using the same image forming apparatus as in the sixth embodiment,
An endurance test for image formation of 30,000 sheets of solid black was performed. FIG. 14 shows the density change due to the number of solid black images formed at that time.
FIG. 15 shows a change in the triboelectric charge amount (triboelectric charge) of the toner.
Shown in The change in the density of the solid black image and the change in the charge amount of the toner were slight. In each temperature and humidity environment, almost no fusion of the toner to the surface of the developing sleeve was observed. Surface roughness Ra of developing sleeve after endurance test
Was 1.48 μm.

Embodiment 10 This embodiment is different from Embodiment 1 in that P
Instead of MMA resin particles, number average particle diameter D1 = 10.5
Micron spherical styrene resin particles were used, and silicone resin fine powder was used instead of Teflon fine powder. Others were treated in the same manner as in Example 1 to obtain surface-modified styrene resin particles with fine silicone resin powder.

The coating solution was prepared according to the following composition.

Phenol resin intermediate 100 parts by weight Surface-modified styrene particles 13 parts by weight Conductive carbon black 22 parts by weight Methanol 60 parts by weight Isopropyl alcohol 240 parts by weight

The viscosity of the coating solution measured at room temperature was 44.5 mPa · s. Using this coating solution, coating was performed on an aluminum cylindrical tube having an outer diameter of 20 mm in the same manner as in Example 1, and a development having a resin coating layer containing surface-modified styrene particles of silicone resin fine powder on the surface was performed. Got a sleeve. The surface roughness R of this developing sleeve
a was 1.68 μm, and the volume resistance was 5.45 Ωcm.

Using the toner of Example 1, a durability test for forming a solid black image was performed in the same manner. FIG. 16 shows a density change according to the number of solid black images formed at that time. The density reduction of the solid black image was slight. In each temperature and humidity environment, almost no fusion of the toner to the surface of the developing sleeve was observed. The surface roughness Ra of the developing sleeve after the durability test was 1.59 μm.

Example 11 In this example, as shown in Table 1, the surface-modified PMMA particles of Example 1 using fine Teflon powder were used.

The coating liquid was prepared according to the following mixing ratio.

Phenol resin intermediate 100 parts by weight Surface-modified PMMA particles 12 parts by weight Carbon black 2 parts by weight Graphite 10 parts by weight Methanol 60 parts by weight Isopropyl alcohol 240 parts by weight

The viscosity of the coating solution measured at room temperature was 53.8 mPa · s. Using this coating solution, coating was performed on an aluminum cylindrical tube in the same manner as in Example 1 to obtain a developing sleeve having on its surface a resin coating layer containing surface-modified PMMA particles of fine Teflon powder. The surface roughness Ra of the developing sleeve is 1.70 μm,
The volume resistance value was 5.80 Ωcm.

Using the toner of Example 1, an endurance test for image formation of 30,000 sheets of solid black was similarly performed. FIG. 17 shows a density change according to the number of solid black images formed at that time. The density reduction of the solid black image was slight. The surface roughness Ra of the developing sleeve after the durability test was 1.45 μm. Also, when the surface of the developing sleeve was observed by FE-SEM, the surface of the resin coating layer on the surface of the developing sleeve was shaved,
Some of the particles in the resin coating layer were exposed on the surface. However, almost no fusion of the toner to the surface of the developing sleeve was observed in each temperature and humidity environment.

Comparative Example 1 A coating liquid was prepared in the same manner as in Example 1 except that the PMMA resin particles were not subjected to the treatment with fine Teflon powder, and the coating liquid was prepared in the same manner as in Example 1, and applied to an aluminum cylindrical tube. And
A developing sleeve having on its surface a resin coating layer containing PMMA resin particles not subjected to surface modification was obtained. The surface roughness Ra of the developing sleeve is 1.58 μm, and the volume resistance value is 7.
It was 20 Ωcm.

In the same manner as in Example 1, an endurance test for forming an image of 30,000 sheets of solid black was performed. FIG. 18 shows a change in density according to the number of formed solid black images at that time. The density of the solid black image was perceptible for practical use, although there was no problem in terms of the number of image formations per 10,000 sheets. The surface roughness Ra of the developing sleeve after the durability test was 1.32 μm. When the surface of the developing sleeve was observed by FE-SEM, the surface layer of the resin coating layer on the surface of the developing sleeve was shaved and exposed to some of the particles in the resin coating layer, and the toner was fused together in each temperature and humidity environment. Was observed.

Comparative Example 2 In Example 2, PMMA resin particles were used without being treated with fine Teflon powder. Except for this, a development sleeve having on the surface a resin coating layer containing PMMA resin particles not subjected to surface modification was obtained in the same manner. The surface roughness Ra of the developing sleeve is 1.37 μm, and the volume resistance value is 8.7.
It was 5 Ωcm.

In the same manner as in Example 1, an endurance test for forming an image of 30,000 sheets of solid black was performed. FIG. 19 shows a density change depending on the number of formed solid black images at that time. Although the density of the solid black image per 10,000 to 15,000 images was formed, there was no problem in practical use, but it was considerably reduced. Further, no fusion of the toner to the surface of the developing sleeve was observed in each temperature and humidity environment. Surface roughness R of developing sleeve after endurance test
a was 1.18 μm.

Comparative Example 3 In Example 3, PMMA resin particles were used without being treated with fine Teflon powder. Except for this, a development sleeve having on the surface a resin coating layer containing PMMA resin particles not subjected to surface modification was obtained in the same manner. The surface roughness Ra of the developing sleeve is 2.18 μm, and the volume resistance value is 7.7.
It was 5 Ωcm.

In the same manner as in Example 1, an endurance test for forming an image of 30,000 sheets of solid black was performed. FIG. 20 shows a change in density according to the number of formed solid black images at that time. A decrease in the density of the solid black image was observed from 15,000 image formation sheets. Further, in each temperature and humidity environment, fusion of the toner to the surface of the developing sleeve was observed. The surface roughness Ra of the developing sleeve after the durability test was 1.18 μm.

Comparative Examples 4 and 5 In Examples 4 and 5, styrene particles were used without being treated with fine powder of polytrifluorochloroethylene resin.
Otherwise, development sleeves having on the surface a resin coating layer containing styrene particles not subjected to surface modification were obtained in the same manner as Comparative Examples 4 and 5. The adhesion amount, surface roughness, and volume resistance of the resin coating layers of the developing sleeves of Comparative Examples 4 and 5 were almost the same as Examples 4 and 5, respectively.

In the same manner as in Example 1, a solid black image formation durability test was performed. FIGS. 21 and 22 show changes in density according to the number of solid black images formed at that time. A decrease in the density of the solid black image was observed from 15,000 to 20,000 sheets of image formation. Further, in each temperature and humidity environment, fusion of the toner to the surface of the developing sleeve was observed.

Comparative Examples 6 and 7 In Examples 6 and 7, phenol resin particles were used without being treated with the fine silicone resin powder, and phenol resin particles not subjected to surface modification were blended in the same manner as in the other cases. A developing sleeve having a resin coating layer on the surface was obtained, and Comparative Examples 6 and 7 were obtained. The adhesion amounts, surface roughness, and volume resistance values of the resin coating layers of the developing sleeves of Comparative Examples 6 and 7 were almost the same as Examples 6 and 7, respectively.

Using the toner used in Example 6, an image formation durability test of 30,000 sheets of solid black was similarly performed. FIGS. 23 and 24 show the density change depending on the number of solid black images formed at that time. From about 20,000 sheets in the latter half of the durability test, a decrease in the density of the solid black image was observed. Further, in each temperature and humidity environment, fusion of the toner to the surface of the developing sleeve was observed.

Comparative Example 8 In Example 8, the coating liquid was prepared by using the spherical styrene resin particles without being treated with the nylon fine powder, and treating them in the same manner except for using the spherical styrene resin particles. hand,
A developing sleeve having on its surface a resin coating layer containing styrene resin particles not subjected to surface modification was obtained.

The viscosity of the coating solution was 58.5 mPa as measured at room temperature.
-It was s. The amount of resin coating layer on the developing sleeve is 8
7 mg, the surface roughness Ra was 1.92 μm, and the volume resistivity was 7.30 Ωcm.

Using the toner used in Example 6, an endurance test for image formation of 30,000 sheets of solid black was similarly performed. FIG. 25 shows a density change according to the number of solid black images formed at that time. From about 20,000 sheets in the latter half of the durability test, a decrease in the density of the solid black image was observed. Further, in each temperature and humidity environment, fusion of the toner to the surface of the developing sleeve was observed. The surface roughness Ra of the developing sleeve after the durability test is 1.63 μm.
Met.

Comparative Example 9 A coating solution was prepared in the same manner as in Example 9 except that the spherical styrene resin particles were not subjected to the treatment with the fine nylon resin powder, and the coating liquid was prepared in the same manner as above, and applied to an aluminum cylindrical tube. ,
A developing sleeve having on its surface a resin coating layer containing styrene resin particles not subjected to surface modification was obtained.

The viscosity of the coating solution was 40.5 mPa at room temperature measurement.
-It was s. The amount of resin coating layer on the developing sleeve is 9
3 mg, the surface roughness Ra was 1.63 μm, and the volume resistivity was 5.50 Ωcm.

Using the toner used in Example 9, an endurance test for forming an image of 30,000 sheets of solid black was similarly performed. FIG. 26 shows a change in density according to the number of solid black images formed at that time, and FIG. 27 shows a change in triboelectric charge amount of toner. A decrease in the density of a solid black image was recognized from about 15,000 sheets, and a decrease in the charge amount of the toner was recognized from about 15,000 sheets. In each temperature and humidity environment, almost no fusion of the toner to the surface of the developing sleeve was observed. The surface roughness Ra of the developing sleeve after the durability test was 1.43 μm.

[0145]

As described above, according to the present invention, a resin coating layer is formed on the surface of a developer carrying member, and fine resin particles are fixed to the surface in the resin coating layer. Include modified spherical resin particles, fine resin particles, silicone resin, fluorine resin, polyethylene, polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane, styrene resin, Alternatively, since it is formed of an acrylic resin, adhesion of toner to the surface of the developer carrying member can be reduced, and the wear resistance of the resin coating layer can be improved. Therefore, the developing device equipped with this developer carrier is not only under normal temperature and normal humidity environment, but also under high temperature and high humidity environment, under low temperature and low humidity environment, even if development is repeated,
A stable and appropriate charge can be applied to the toner on the developer carrier, and even when a large number of images are formed, a high quality image with no density reduction or ghost, uniform density unevenness, fogging, scattering, etc. is obtained. Obtainable.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a developing device of the present invention.

FIG. 2 is a cross-sectional view illustrating a surface portion of a developing sleeve installed in the developing device of FIG.

FIG. 3 is a cross-sectional view showing another embodiment of the developing device of the present invention.

FIG. 4 is a sectional view showing still another embodiment of the developing device of the present invention.

FIG. 5 is a cross-sectional view illustrating an example of a conventional developing device.

FIG. 6 is a graph showing a density change according to the number of images formed in an image formation durability test of a solid black image in Example 1 of the present invention.

FIG. 7 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Example 2.

FIG. 8 is a graph showing a density change according to the number of formed images in an image formation durability test of a solid black image in Example 3.

FIG. 9 is a graph showing a density change according to the number of formed images in an image formation durability test of a solid black image in Example 4.

FIG. 10 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Example 5.

FIG. 11 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Example 6.

12 is a graph showing a density change according to the number of formed images in an image formation durability test of a solid black image in Example 7. FIG.

FIG. 13 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Example 8.

FIG. 14 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Example 9.

FIG. 15 is a graph showing a change in the amount of triboelectric charge of toner according to the number of images formed in an image formation durability test of a solid black image in Example 9.

FIG. 16 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Example 10.

FIG. 17 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Example 11.

FIG. 18 is a graph showing a density change according to the number of formed images in an image formation durability test of a solid black image in Comparative Example 1.

FIG. 19 is a graph showing a density change according to the number of formed images in an image formation durability test of a solid black image in Comparative Example 2.

FIG. 20 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Comparative Example 3.

FIG. 21 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Comparative Example 4.

FIG. 22 is a graph showing a density change according to the number of formed images in an image formation durability test of a solid black image in Comparative Example 5.

FIG. 23 is a graph showing a density change according to the number of formed images in an image formation durability test of a solid black image in Comparative Example 6.

FIG. 24 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Comparative Example 7.

FIG. 25 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Comparative Example 8.

FIG. 26 is a graph showing a density change depending on the number of formed images in an image formation durability test of a solid black image in Comparative Example 9.

FIG. 27 is a graph showing a change in the triboelectric charge amount of toner according to the number of images formed in an image formation durability test of a solid black image in Comparative Example 9.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photosensitive drum 2 regulating blade 4 magnetic toner 6 sleeve base 7 resin coating layer 8 developing sleeve 11 elastic plate 12 resin 13 spherical resin particles 14 resin particles of fine particle size (surface modified particles)

Continuation of the front page (72) Inventor Yasuhide Goseki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kazuki Saiki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-8-185042 (JP, A) JP-A-8-305155 (JP, A) JP-A-3-163575 (JP, A) JP-A-8-15977 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) G03G 13/08-13/095 G03G 15/08-15/095

Claims (8)

(57) [Claims] 1. A developer carrier that carries a developer and conveys the developer to a developing section facing the latent image carrier and uses the developer to develop a latent image formed on the latent image carrier. The agent carrier is formed by forming a resin coating layer containing spherical resin particles on the surface of a metal cylinder, and the spherical resin particles contained are formed by fixing fine resin particles to the surface. The fine resin particles, silicone resin, fluororesin, polyethylene, polyethersulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane,
A developer carrier formed of a styrene resin or an acrylic resin. 2. The spherical resin particles have a size of 0.3 to 30 μm.
2. The developer carrier according to claim 1, wherein the fine resin particles have a particle diameter ratio of 0.2 or less to the spherical resin particles. 3. The developer carrier according to claim 1, wherein said resin film layer contains a conductive fine powder. 4. The developer carrier according to claim 1, wherein said resin film layer contains a lubricating substance. 5. A developing method in which a developer is carried on a developer carrier and a developer layer regulating member forms a thin layer of the developer, and the developer is opposed to the latent image carrier by the developer carrier. In the developing device which transports the developer to the latent image carrier formed on the latent image carrier, wherein the developer carrier has a spherical resin whose surface is modified by fine resin particles. A resin coating layer containing particles is formed on the surface of a metal cylinder, and the resin particles having the fine particle diameter are silicon resin, fluororesin, polyethylene, polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, A developing device formed of polyester, polyurethane, styrene resin, or acrylic resin. 6. The spherical resin particles have a size of 0.3 to 30 μm.
The developing device according to claim 5, wherein the fine resin particles have a particle diameter ratio of 0.2 or less. 7. The developing device according to claim 5, wherein the resin coating layer contains a conductive fine powder. 8. The developing device according to claim 5, wherein said resin film layer contains a lubricating substance.