JPH09185246A - Developer carrier and developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To apply a stable and proper electric charge to toner, even if development is repeated and to obtain an image of high quality, at the time of forming images for a large number of sheets as well by incorporating globular resin grains constituted in such a manner that resin grains having a fine grain size are fixed on the surface, in a resin coating film layer formed on the surface of a developer carrier. SOLUTION: On the surface of the substrate 6 of a metallic cylindrical tube sleeve, the resin coating film layer 7 incorporating the globular resin grains 13 whose surfaces are improved in such a manner that the resin grains 14 having the fine grain size are fixed on the surface is formed, to constitute a developing sleeve 8. The resin coating film layer 7 is constituted in such a manner that the globular resin grains 13 are dispersed in a resin 12. As the grain size of the globular resin grain 13, a number of grains averaged size is preferably 0.3-30μm, more preferably 1-25μm. As the grain size of the surface improving grain 14, it is preferable that the grain size ratio of the grain 14 to the globular resin grain 13 is <=0.2. As the resin used for the surface improving grains 14, low surface energy one such as silicone resin and fluororesin is especially preferable because a surface improving effect is great.

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 the latent image holding surface of a latent image bearing member such as the above, and a developer bearing member thereof.

More specifically, a dry carrier in the form of powder is supplied to and carried on a developer carrier, and the carried developer is regulated to a thin layer by a layer thickness regulating member to retain a latent image on the latent image carrier. The present invention relates to a developing device of a type in which a latent image is developed by being conveyed to a developing portion facing a surface, and a developer carrying member thereof.

[0003]

2. Description of the Related Art Conventionally, for example, in a developing device for developing an electrostatic latent image formed on the surface of a photosensitive drum as a latent image carrier with a magnetic toner of a one-component developer, toner particles are separated from each other. And the friction between the developing sleeve as the developer carrier and the magnetic toner particles give the magnetic toner particles a charge having a polarity opposite to that of the electrostatic latent image on the photosensitive drum with respect to the development reference potential. The toner was applied to the developing sleeve extremely thinly by the regulating member to form a thin toner layer, and was conveyed to the developing unit where the photosensitive drum and the developing sleeve faced each other, and was installed in the developing sleeve in the developing unit. Due to the rising of magnetic toner by the magnetic field of the magnet and the action of the developing bias applied to the developing sleeve, the toner flies and adheres to the surface of the photosensitive drum to develop, and the electrostatic latent image is converted to a toner image. Which visualizes is known.

FIG. 5 shows an example of the configuration of the above conventional developing device. In FIG. 5, reference numeral 3 is a hopper containing a magnetic toner 4 of a one-component developer, and a developing sleeve 8 is rotatably installed in an arrow A direction at an opening of the hopper 3 facing the photosensitive drum 1. A magnet 5 for magnetically attracting and holding the toner 4 on the developing sleeve 8 is disposed in the non-rotating member 8. A stirring blade 10 for stirring and conveying the toner 4 toward the developing sleeve 8 is installed in the hopper 3, and the layer thickness of the toner 4 on the developing sleeve 8 is provided above the opening of the hopper 3. A regulating blade 2 for regulating the above is attached to the developing sleeve 8 with a predetermined gap. A bias power source 9 is connected to the developing sleeve 8.

Developing sleeve 8 used in these methods
For example, a metal or alloy thereof is formed into a cylindrical shape, and the surface thereof is treated to a predetermined surface roughness by electrolysis, blasting, sanding or the like. But,
In this case, in the toner layer formed on the surface of the developing sleeve 8 by the regulation blade 2, the toner near the surface of the developing sleeve has a very high excess electric charge,
The surface of the developing sleeve is strongly attracted to the surface of the developing sleeve due to the mirroring force, so that there is no chance of friction between the toner and the developing sleeve, so that the toner cannot obtain a suitable charge. Under such a condition, sufficient development and transfer are not performed, and the obtained image has uneven density and scattering of characters.

In order to prevent the generation of the toner having such an excessive charge and the strong adhesion of the toner, for example, JP-A-1-277264 and JP-A-3-36570 are disclosed.
As disclosed in the publication, it has been proposed to form a resin coating layer composed of a resin, conductive fine powder, a solid lubricant, etc. on the surface of a developing sleeve and use it in a developing device. Further, in order to secure 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 described in JP-A-3-200986. Proposals have been made to add it.

However, in recent years, there has been a further demand for reducing the energy consumption of the LBP main body and the copying machine, and in order to reduce the energy required for fixing, the study of low-temperature fixing of toner is advanced. Therefore, as represented by surf fixing and the like, it is required to melt the toner in a shorter time and at a lower temperature. Therefore, the binder resin of the toner tends to have a low 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 made smaller, and as a result, the above-mentioned toner is likely to adhere strongly to the surface of the developing sleeve and the surface of the developing sleeve is Easily polluted by.

Further, although the developing device is made into a cartridge or a unit, the durability of the developing cartridge or the developing unit is further improved so that a high quality image can be stably provided for a long period of time. Is required to

[0009]

Conventionally, for example, the durable number of sheets required for a developing sleeve used in a developing cartridge has been about 2,000 to 8,000 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 order to increase the capacity of the cartridge and to cope with the toner replenishment method.
Further, in order to improve the image quality, there is a tendency that the regulation of toner is strengthened and the toner layer on the developing sleeve is made thinner.
The physical load on the toner and the developing sleeve is increasing.

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

On the other hand, in the technique disclosed in Japanese Patent Laid-Open No. 3-200986, a preferable irregularity is formed on the surface of the resin coating layer by adding a small amount, and therefore the irregularity is improved. However, it is still insufficient in terms of abrasion and peeling of the added particles of the resin coating layer or toner adhesion.

The present inventors have conducted various studies to prevent abrasion and peeling of the added particles added to the resin coating layer on the surface of the developing sleeve or to prevent toner adhesion. The inventors have found that it is sufficient to use modified spherical resin particles, and have completed the present invention.

Therefore, the object of the present invention is to provide a stable and appropriate electric charge to the toner on the developer carrying member even if the development is repeated, and there is no reduction in density or generation of ghost even when a large number of images are formed. It is an object of the present invention to provide a developer carrier capable of obtaining a high-quality image that is uniform and has no density unevenness, fog, or scattering.

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

Still another object of the present invention is to provide a developer carrying member 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 condition for a long period of time and capable of stably obtaining a high quality image. is there.

[0017]

The above object can be 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 provides the developer for developing the 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 are formed by fixing fine particle resin particles on the surface. The developer carrying member is characterized by being modified.

In another aspect of the present invention, a latent image is formed on the developer carrying member while the developer is carried on the developer carrying member and the developer layer regulating member forms a thin layer of the developer. In a developing device that conveys the developer to the developing unit facing the carrier and provides the developer with the latent image formed on the latent image carrier,
The developer carrying body is a developing device characterized in that a resin coating layer containing spherical resin particles whose surface is modified with fine particle diameter resin particles is formed on the surface of a metal cylinder. .

Preferably, the spherical resin particles have a particle size of 0.3.
The resin particles having a number average particle diameter of ˜30 μm and a fine particle diameter have a particle diameter ratio of 0.2 or less to the spherical resin particles. The fine resin particles have a low surface energy. In addition, the resin coating layer may contain 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 is an image bearing member that carries an electrostatic latent image formed by a known process, for example, an electrophotographic photosensitive drum, and a developing device is an electrostatic latent image on the photosensitive drum 1 rotated in the direction of arrow B. Used to develop a latent image.

The present developing device is provided with 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 portion of the hopper 3 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. According to the present invention, the resin coating layer 7 has resin particles of fine particle size on the surface. It contains spherical resin particles whose surface has been modified by fixing. The resin coating layer 7 will be described later.

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

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 portion where the developing sleeve 8 and the photosensitive drum 1 face each other. To do. In the carrying process, the toner 4 acquires frictional charge capable of developing the electrostatic latent image on the photosensitive drum 1 by friction with the developing sleeve 8.

A hopper 3 in which a developing sleeve 8 is arranged in order to regulate the layer thickness of the magnetic toner 4 conveyed to the developing section.
On top of the opening of the control blade 2 made of ferromagnetic metal
Is installed. The regulation 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. In the magnetic toner 4 on the developing sleeve 8, the magnetic force line from the magnetic pole N1 of the magnet 5 is regulated by the blade 2.
Then, a thin layer of the magnetic toner 4 is formed on the developing sleeve 8 while being regulated by being concentrated on the developing sleeve 8. A non-magnetic blade can also be used as the regulation blade 2.

The thin layer of the magnetic toner 4 formed on the developing sleeve 8 is preferably thinner 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 portion is equal to or larger than the minimum gap between the developing sleeve 8 and the photosensitive drum 1, that is, a contact type developing device.

In order to avoid complication 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 source 9 in order to fly the magnetic toner 4 carried on the developing sleeve 8 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 (the area where the magnetic toner 4 is adhered and visualized) of the electrostatic latent image and the potential of the background portion is the developing voltage. It is preferably 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 whose direction is alternately inverted in the developing portion. In this case, it is preferable to apply to the developing sleeve 8 an alternating bias voltage in which a DC voltage component having a value between the potential of the image portion and the potential of the background portion is superimposed.

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

In the present invention, as described above, the spherical resin particles obtained by fixing the resin particles having a fine particle diameter on the surface of the sleeve substrate 6 made of a metal (including alloy) cylindrical tube and modifying the surface thereof. To form 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 resin film layer 7 is formed on the surface of the base 6 of the developing sleeve 8, and the resin film layer 7 includes spherical resin particles 13 having resin particles 14 having a fine particle diameter fixed to the surface thereof. It is dispersed in the resin 12.

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, fluororesin,
Thermoplastic resins such as fibrin resin, acrylic resin, epoxy resin, polyester resin, alkyd resin, phenol resin, melamine resin, polyurethane resin, urea resin, silicone resin, polyimide resin, etc. Can be used. Among them, those with releasability such as silicone resin and fluororesin, or mechanical properties such as polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane, styrene resin, acrylic resin The superior one is more preferable.

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

The resin used for such spherical resin particles includes 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. Examples thereof include particles, phenol resin particles, polyurethane resin particles, styrene resin particles, and benzoguanamine particles.

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

In the present invention, the adhesion of 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 modifying particles 14 having a fine particle diameter are fixed to the surface of the spherical resin particles 13 contained in the resin coating layer 7 for modification.

The particle diameter of the surface-modified particles 14 is such that the particle diameter ratio with the spherical resin particles 13, that is, (particle diameter of the surface-modified particles 14 / particle diameter of the spherical resin particles 13) is 0.2 or less. Is preferred. The surface-modified particles 14 made of resin particles having a fine particle size, which are stronger in wear strength than the spherical resin particles 13, or the surface-modified particles 14 made of resin particles having a small surface energy of low surface energy.
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 so that the surface of the spherical resin particles 13 can be prevented from being worn and the adhesion of toner can be reduced. it can. Therefore, the developing sleeve 8 having the resin coating layer 7 containing the surface-modified spherical resin particles 13 formed on the surface thereof reduces the adhesion of toner to the surface and improves the abrasion resistance of the resin coating layer 7. be able to.

The resin used for the surface-modified particles 14 is
Generally known resins can be used, but those having a low surface energy such as silicone resin, fluororesin, and polyethylene are particularly preferable because they have a large surface modifying effect. Further, those having excellent 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 imparting property, phenol, acrylic, silicone, fluorine-based, nylon and other N-containing resins are preferable.

Specifically, considering the adhesiveness between the spherical resin particles 13 and the resin 12 for forming the resin coating layer 7, the chargeability with the toner, the difficulty of fusion bonding, and the like, the resin is appropriately selected from the above resins. It is better to select and use it.

The surface of the spherical resin particles 13 is modified by the particles 13
A resin powder of the surface-modified particles 14 is externally added to the surface of the particles 13, and the particles are fixed to a part or the whole surface of the particles 13 by heat treatment or mechanical impact to cover the surface, or the surface-modified particles 1
This can be carried out by, for example, a method of covering the surface of the particles 13 with the resin solution of No. 4, drying and curing the particles 13 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. As the conductive agent added to the resin coating layer 7, conductive carbon black, metal powder of aluminum, copper, nickel, silver or the like, antimony oxide,
Conductive metal oxides such as indium oxide, titanium oxide, tin oxide and aluminum oxide, short metal fibers and carbon fibers 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, Loresta SP is used for measuring the volume resistance of the resin coating layer 7.
MCP-T500 (manufactured by Mitsubishi Yuka) was used.

A solid lubricant may be further added to the resin coating layer 7. For example, graphite, molybdenum disulfide, boron nitride, zinc stearate, etc. are added in an amount of 0.1 to 400% with respect to the resin,
It is preferably about 1 to 200%.

In the present invention, the surface roughness of the developing sleeve 8 is 0.5 in terms of arithmetic average roughness Ra (JISB0601).
˜5 μm is preferable, and 1 to 3.5 μm is more preferable.
The surface roughness Ra is measured by SE-3300 (Kosaka Laboratory).
With a feed speed of 0.5 mm / sec and a measurement length of 4.
It was measured by 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.

Toners are roughly classified into dry type toners and wet type toners. Since wet type toners have a large problem of solvent volatilization, currently dry type toners are the mainstream. Toner is mainly melt-kneaded with resin, release agent, charge control agent, colorant, etc.,
It is a fine powder that is pulverized after being singulated, and then classified 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 and p-chlorostyrene and their substitution products; styrene-propylene copolymers, styrene-vinyltoluene copolymers, styrene-ethyl acrylate copolymers. 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 acid resin, rosin, modified rosin, tempel resin,
Phenolic resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, paraffin wax, carnauba wax and the like can be used alone or in combination.

The toner may contain a pigment. For example, carbon black, nigrosine dye, lamp black, Sudan Black SM, First Yellow G, Benzidine Yellow, Pigment Yellow, India First Orange, Irgadine 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, etc. can be applied.

In order to use the toner as a magnetic toner,
Magnetic powder may be contained in the toner. As such a magnetic powder, a substance that is magnetized by being placed in a magnetic field is used, and a powder of a ferromagnetic metal such as iron, cobalt or 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, Examples include various waxes. Furthermore, if necessary, a charge control agent for facilitating positive or negative charge may be added.

FIG. 3 is a constitutional view showing another embodiment of the developing device of the invention. In this developing device, the developing sleeve 8
As a member for controlling the layer thickness of the upper magnetic toner 4, 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. The characteristic is that the elastic plate 11 is pressed against the developing sleeve 8 in a posture opposite to the rotating 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
An even thinner toner layer can be formed on top. Also in the present embodiment, the developing sleeve 8 is a spherical resin particle obtained by fixing resin particles of fine particle size on the surface of the sleeve substrate 6 formed of a metal (including alloy) cylindrical tube and modifying the surface. Is formed by forming a resin coating layer 7 containing.

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

With this developing device, a thinner toner layer can be formed on the developing sleeve 8 as in the developing device shown in FIG. Similarly, the developing sleeve 8 contains spherical resin particles whose surface is modified by fixing resin particles having a fine particle diameter on the surface of the sleeve substrate 6 formed of a metal (including alloy) cylindrical tube. It is configured 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 when a magnetic toner of 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 with reference to specific examples, but the present invention is not limited thereto.

Example 1 As the spherical resin particles 13 mixed in the resin coating layer 7 on the surface of the developing sleeve 8, the number average diameter D1 crosslinked with a crosslinking agent is used.
= 12.5 μm polymethylmethacrylate (PMMA)
Particles were used. The PMMA particles are produced by the suspension method and have a spherical shape. Teflon fine powder was used as the surface-modified particles 14.

A 75 liter Henschel mixer jacket 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 fix the Teflon fine powder to the surface of the PMMA particles. , The surface was modified. Electron microscope (FE-SEM) was used to measure the surface-modified PMMA particles with this Teflon fine powder.
The surface of the PMMA particles was sufficiently covered with the Teflon particles as observed by (1).

Next, a coating liquid for the resin coating layer was prepared with the following compounding ratio.

Phenolic 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 Isopropyl alcohol 240 parts by weight

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

This coating solution was applied to a developing sleeve substrate. The developing sleeve substrate is an aluminum cylindrical tube having an outer diameter of 20 mm. This cylindrical tube was erected and rotated, and the coating liquid was applied to a uniform film thickness while lowering the spray gun at a constant speed. Then, the coating film was dried and cured in a drying oven to obtain a developing sleeve having a resin coating layer containing surface-modified PMMA particles on its surface. When the surface roughness of this developing sleeve was measured, it was 1.53 μ in Ra notation.
m.

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

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

Next, the above developing sleeve was incorporated into a developing device of a copying machine NP-6016 manufactured by Canon and used for development to form a solid black image. Image formation is 15 ℃
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, the toner was replenished to the developing device in such a manner that 100 g was replenished every time 100 g was consumed.

The toner used has 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, then heated and mixed by a twin-screw extruder, cooled, and then coarsely pulverized, finely pulverized and classified,
A toner classified product having a weight average particle size of 8 μm, a particle number distribution of which the number% of particles having a particle size of 4.0 μm or less is 16.3%, and the weight% of particles having a particle size of 10.1 μm or more is 0.86%. Obtained. The particle size distribution of the toner classified product was measured by attaching a 100 μm aperture to Coulter Multisizer II 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 toner classified product and used as a toner.

FIG. 6 shows a change in density depending on the number of formed solid black images in this embodiment. In FIG. 6, the graph shows the case where the broken line of ○ is 15 ° C./10%, the broken line of × is 23 ° C./60%, and the broken line of Δ is 32 ° C./85% (hereinafter, FIG. The same in FIG. 27). FIG.
As shown in (3), the density decrease of the solid black image due to the image formation up to 30,000 sheets was slight in each temperature and humidity environment.

The surface roughness Ra of the developing sleeve after the durability test of 30,000 sheets of image formation was 1.45 μm. The results of observing the surface of the developing sleeve after the durability test by FE-SEM are shown in Table 1 above.

In Table 1, the symbols have the following meanings regarding toner fusion. ◎: No fusion, ○: Almost no, ○
△: Slight, △: Somewhat bad, △ x: Quite bad,
×: Bad. In this embodiment, the surface layer of the resin coating layer on the surface of the developing sleeve was scraped off, and a part of the particles in the coating layer was exposed on the surface. It was hardly recognized.

[0069]

[Table 1]

Example 2 In this example, as shown in Table 1 in Example 1, P
The number average particle diameter D1 of the MMA particles was 3.2 μm. For 10 kg of these PMMA particles, 40 teflon fine powder is used.
0 g was added. Otherwise, perform the same processing as in Example 1,
Surface-modified PMMA particles with fine Teflon powder were obtained.

The coating liquid was prepared in the following mixing ratio. The treatment method is the same as in Example 1.

Phenolic 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

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

Similar to Example 1, the durability test of 30,000 sheets of image formation was conducted. FIG. 7 shows the density change of the solid black image depending on the number of formed images. The density decrease of the solid black image was slight. Also, in each temperature and humidity environment, almost no toner fusion on 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 in Example 1, PMMA particles having a number average particle diameter D1 = 25.3 μm were used. Others were treated in the same manner as in Example 1 to obtain surface-modified PMMA particles using Teflon fine powder.

The coating liquid was prepared with the following compounding ratio.

Phenolic resin intermediate 100 parts by weight Surface-modified PMMA particles 7 parts by weight Conductive tin oxide 13 parts by weight Conductive carbon black 7 parts by weight Methanol 50 parts by weight Isopropyl alcohol 250 parts by weight

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

In the same manner as in Example 1, a durability test was conducted with 30,000 sheets of image formed. At that time, the change in the density of the solid black image depending on the number of images formed was small as shown in FIG. Also, in each temperature and humidity environment, almost no toner fusion on 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, instead 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 were surface-treated with 300 g of polytrifluorochloroethylene fine powder,
Polytrifluorochloroethylene fine powder was adhered to the surface of the styrene particles to obtain surface-modified styrene particles with the polytrifluorochloroethylene fine powder.

A coating solution was prepared with the following compounding ratio. The treatment method is the same as in Example 1.

Phenol resin intermediate 100 parts by weight Surface-modified styrene particles 15 parts by weight Crystalline graphite (average particle size 4 μm) 30 parts by weight Conductive carbon black 5 parts by weight Methanol 60 parts by weight Isopropyl alcohol 240 parts by weight

When the viscosity of this coating liquid was measured at room temperature, it was 62.9 mPa · s. Using this coating solution, a cylindrical aluminum tube having an outer diameter of 20 mm was coated in the same manner as in Example 1, and a resin coating layer containing surface-modified styrene particles with polytrifluorochloroethylene fine powder was coated on the surface. A developing sleeve having the above was obtained. The surface roughness Ra of this 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, a durability test of image formation on 30,000 solid black images was conducted. FIG. 9 shows a density change depending on the number of formed solid black images 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. Further, 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 scraped, and some particles in the resin coating layer were exposed on the surface. However, in each temperature and humidity environment, almost no toner fusion on the surface of the developing sleeve was observed.

Example 5 In this example, as shown in Table 1, the number average particle size D1 of the styrene particles in Example 4 was set to 25.5 μm.
Other than that was treated in the same manner as in Example 4 to obtain surface-modified styrene particles by polytrifluorochloroethylene fine powder.

The coating solution 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

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

Similarly, a durability test was performed on 30,000 sheets of image formation. FIG. 10 shows the density change of the solid black image depending on the number of images formed at that time. The density decrease of the solid black image was slight. Also, in each temperature and humidity environment, almost no toner fusion on 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 the spherical resin particles, and silicone resin powder was used as the surface-modified particles. .

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

The coating liquid was prepared by the following composition.

Phenolic resin intermediate 100 parts by weight Surface modified phenol particles 13 parts by weight Conductive tin oxide 9 parts by weight Conductive carbon black 11 parts by weight Molybdenum disulfide 5 parts by weight Methanol 60 parts by weight Isopropyl alcohol 240 parts by weight

When the viscosity of this coating solution was measured at room temperature, it was 48.5 mPa · s. Using this coating solution, a cylindrical aluminum tube was coated 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 containing silicone resin powder. The adhered amount of this resin coating layer was 95 mg / m ² (is the unit acceptable?). 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 used had the following formulation. The treatment 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

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

Next, as an image forming apparatus, EP-of laser jet IV Si manufactured by Hewlett-Packard (HP) Co., Ltd.
The above-mentioned developing sleeve was processed and attached to the N cartridge. Then, using the laser jet IV Si, the durability test for image formation of 30,000 solid black images was conducted as before.

FIG. 11 shows the change in density depending on the number of formed solid black images at that time. As shown in FIG. 11, the density decrease of the solid black image was slight. Also, in each temperature and humidity environment, almost no toner fusion on 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 phenolic resin particles with the silicone resin powder of Example 6 were used.

The coating liquid was prepared with the following compounding 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

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

Similar to Example 6, this developing sleeve was used for Laser Jet IV Si (Hewlett Packard Co.), and the toner of Example 6 was used to carry out an endurance test of image formation of 30,000 solid black images.

FIG. 12 shows the density change depending on the number of formed solid black images at that time. The density decrease of the solid black image was slight. Also, in each temperature and humidity environment, almost no toner fusion on 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. Other than that, as in Example 6, 300 g of nylon fine powder was added to 10 kg of styrene resin particles,
It was treated by the same method and fixed on the surface to obtain surface-modified styrene resin particles with fine nylon powder.

The coating liquid was prepared by the following composition.

Phenol resin intermediate 100 parts by weight Surface modified styrene particles 7 parts by weight Crystalline graphite (average particle size 4 μm) 15 parts by weight Conductive carbon black 4 parts by weight Methanol 60 parts by weight Isopropyl alcohol 240 parts by weight

When the viscosity of this coating solution was measured at room temperature, it was 59.5 mPa · s. Using this coating solution, a cylindrical aluminum tube having an outer diameter of 16 mm was coated 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 modified with nylon fine powder. Got Adhesion amount of resin coating layer is 92 mg / m ²
Met. The surface roughness Ra of this 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 similarly, a durability test of image formation of 30,000 solid black images was conducted. At that time, the change in the density of the solid black image depending on the number of images formed was small as shown in FIG. Also, in each temperature and humidity environment, almost no toner fusion on 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. Other than that, Example 8
The same treatment as described above was performed to obtain surface-modified styrene resin particles with fine nylon powder.

The coating liquid was prepared by 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

When the viscosity of this coating solution was measured at room temperature, it was 42.5 mPa · s. Using this coating solution, a cylindrical aluminum tube having an outer diameter of 16 mm was coated 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 modified with nylon fine powder. Got Adhesion amount of resin coating layer 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 used had the following formulation.

Styrene-butyl acrylate-maleic acid n-butyl 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

After mixing the above raw materials with a Henschen mixer, heating and mixing with a twin-screw extruder, and then cooling, coarse pulverization, fine pulverization and classification are carried out,
Toner classification having a weight average particle size of 6.58 μm, a particle number distribution of 17.3% in the number of particles having a particle size of 4.0 μm or less and 1.2% in the weight% of particles having a particle size of 10.1 μm or more. I got the goods. 1.1 parts by weight of hydrophobic colloidal silica was externally added to 100 parts by weight of this toner classified product and used as a toner.

Using the same image forming apparatus as in Example 6,
An endurance test for image formation of 30,000 solid black images was performed. FIG. 14 shows a density change depending on the number of formed solid black images at that time.
FIG. 15 shows changes in the toner triboelectric charge amount (tribo).
Shown in The decrease in the density change of the solid black image and the change of the charge amount of the toner were slight. Also, in each temperature and humidity environment, almost no toner fusion on the surface of the developing sleeve was observed. Surface roughness Ra of developing sleeve after durability test
Was 1.48 μm.

Example 10 In this example, as shown in Table 1, in Example 1, P
Instead of MMA resin particles, number average particle diameter D1 = 10.5
Spherical styrene resin particles of μm 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 powder of silicone resin.

The coating liquid was prepared with 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

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

Using the toner of Example 1, a solid black image forming durability test was conducted in the same manner. FIG. 16 shows a density change depending on the number of formed solid black images at that time. The density decrease of the solid black image was slight. Also, in each temperature and humidity environment, almost no toner fusion on 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 using the Teflon fine powder of Example 1 were used.

The coating liquid was prepared with the following compounding 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

When the viscosity of this coating solution was measured at room temperature, it was 53.8 mPa · s. Using this coating solution, a cylindrical aluminum tube was coated 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 this developing sleeve is 1.70 μm,
The volume resistance value was 5.80 Ωcm.

Using the toner of Example 1, similarly, a durability test of image formation of 30,000 solid black images was conducted. FIG. 17 shows a density change depending on the number of formed solid black images at that time. The density decrease 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 layer of the resin coating layer on the surface of the developing sleeve was scraped,
Some of the particles in the resin coating layer were exposed on the surface. However, in each temperature and humidity environment, almost no toner fusion on the surface of the developing sleeve was observed.

Comparative Example 1 A coating solution was prepared in the same manner as in Example 1 except that PMMA resin particles were used without treatment with Teflon fine powder, and the coating was applied to an aluminum cylindrical tube. Then
A developing sleeve having on its surface a resin coating layer containing PMMA resin particles not surface-modified was obtained. The surface roughness Ra of this 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, the durability test of image formation of 30,000 solid black images was conducted. FIG. 18 shows the change in density of the solid black image depending on the number of formed images. The density of the solid black image was about 10,000 per image formation, so there was no problem in practical use, but it was considerably lowered. 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 scraped in each temperature and humidity environment, and some of the particles in the resin coating layer were exposed to the surface and the toner fusion occurred. Was recognized.

Comparative Example 2 In Example 2, PMMA resin particles were used without being treated with the Teflon fine powder. Other than that was carried out similarly, and the developing sleeve which has the resin film layer which mix | blended the PMMA resin particle which is not surface-modified on the surface was obtained. The surface roughness Ra of this 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, a durability test of image formation on 30,000 solid black was performed. FIG. 19 shows a density change depending on the number of formed solid black images at that time. The density of the solid black image was around 10,000 to 15,000 sheets, so there was no problem in practical use, but it was considerably lowered. Further, in each temperature and humidity environment, no toner fusion on the surface of the developing sleeve was observed. Surface roughness R of developing sleeve after durability test
a was 1.18 μm.

Comparative Example 3 In Example 3, PMMA resin particles were used without treatment with Teflon fine powder. Other than that was carried out similarly, and the developing sleeve which has the resin film layer which mix | blended the PMMA resin particle which is not surface-modified on the surface was obtained. The surface roughness Ra of this 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, a durability test for image formation of 30,000 solid black images was conducted. FIG. 20 shows the density change of the solid black image depending on the number of formed images. From 15,000 images formed, a decrease in the density of solid black images was observed. Further, in each temperature and humidity environment, toner fusion on the surface of the developing sleeve was recognized. 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 treatment with the polytrifluorochloroethylene resin fine powder,
In the same manner except for the above, developing sleeves having a resin coating layer on the surface of which styrene particles having no surface modification were blended were obtained, and Comparative Examples 4 and 5 were obtained. The adhesion amount of the resin coating layer, the surface roughness and the volume resistance value of the developing sleeves of Comparative Examples 4 and 5 were almost the same as those of Examples 4 and 5, respectively.

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

Comparative Examples 6 and 7 In Examples 6 and 7, the phenol resin particles were used without being treated with the silicone resin fine powder, and otherwise the phenol resin particles not surface-modified were blended in the same manner. Development sleeves having a resin coating layer on the surface thereof were obtained and designated as Comparative Examples 6 and 7, respectively. The amount of resin coating layer adhered, the surface roughness and the volume resistance of the developing sleeves of Comparative Examples 6 and 7 were almost the same as those of Examples 6 and 7, respectively.

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

Comparative Example 8 In Example 8, the spherical styrene resin particles were used without being treated with the fine nylon powder, and otherwise the same treatment was carried out to prepare a coating solution, which was applied to an aluminum cylindrical tube. 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 is 58.5 mPa 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 resistance value was 7.30 Ωcm.

Using the toner used in Example 6, similarly, a durability test of image formation of 30,000 solid black images was conducted. FIG. 25 shows the density change of the solid black image depending on the number of formed images. From around 20,000 sheets in the latter half of the durability test, a decrease in the density of solid black images was observed. Further, in each temperature and humidity environment, toner fusion on the surface of the developing sleeve was recognized. 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 treated with the fine nylon resin powder, and were coated on 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 is 40.5 mPa at room temperature.
-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 resistance value was 5.50 Ωcm.

Using the toner used in Example 9, the durability test of image formation of 30,000 solid black images was similarly conducted. FIG. 26 shows a change in the density of the solid black image depending on the number of formed images, and FIG. 27 shows a change in the triboelectric charge amount (tribo) of the toner. A decrease in the density of a solid black image was observed after about 15,000 sheets, and a decrease in the amount of charged electric charge of the toner was observed after about 15,000 sheets. Also, in each temperature and humidity environment, almost no toner fusion on 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, in the present invention, the resin coating layer is formed on the surface of the developer carrying member, and the resin coating layer is formed by fixing the resin particles having the fine particle diameter to the surface. Since the modified spherical resin particles are contained, the adhesion of the toner to the surface of the developer carrying member can be reduced and the abrasion resistance of the resin coating layer can be improved. Therefore, the developing device equipped with this developer carrier is not only under normal temperature / humidity environment, but also under high temperature / high humidity environment, low temperature / low humidity environment,
Even if the development is repeated, the toner on the developer carrier can be stably and appropriately charged, and even when a large number of images are formed, there is no density decrease or ghost, and the density is uniform and uneven. You can get high quality images.

[Brief description of the drawings]

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

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

FIG. 3 is a sectional view showing another embodiment of the developing device of the 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 change in density depending on 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 changes in density depending on the number of images formed in an image formation durability test of a solid black image in Example 2.

FIG. 8 is a graph showing changes in density depending on the number of images formed in an image forming durability test of a solid black image in Example 3.

FIG. 9 is a graph showing changes in density depending on the number of images formed in an image forming durability test of a solid black image in Example 4.

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

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

FIG. 12 is a graph showing changes in density depending on the number of image formations in an image formation durability test of a solid black image in Example 7.

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

FIG. 14 is a graph showing changes in density depending on the number of image formed sheets in an image forming durability test of a solid black image in Example 9.

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

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

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

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

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

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

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

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

FIG. 23 is a graph showing changes in density depending on the number of images formed in an image forming durability test of a solid black image in Comparative Example 6.

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

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

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

[Explanation of symbols]

 1 Photosensitive Drum 2 Control Blade 4 Magnetic Toner 6 Sleeve Base 7 Resin Coating Layer 8 Developing Sleeve 11 Elastic Plate 12 Resin 13 Spherical Resin Particles 14 Fine Particle Resin Particles (Surface Modified Particles)

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Yasuhide Goseki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Ikki Saiki 3-30-2 Shimomaruko, Ota-ku, Tokyo Kya Non non corporation

Claims (10)

[Claims] 1. A developer carrier for carrying a developer, carrying the developer to a developing section facing the latent image carrier, and developing the 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 contained spherical resin particles are formed by fixing fine particle resin particles on the surface. A developer carrying member characterized by being modified. 2. The spherical resin particles have a particle size of 0.3 to 30 μm.
2. The developer carrying member according to claim 1, wherein the resin particles having a number average particle diameter of 1 and a particle diameter ratio of the fine resin particles to the spherical resin particles are 0.2 or less. 3. The developer carrying member according to claim 1, wherein the resin particles having a fine particle diameter are made of a resin having a low surface energy. 4. The developer carrier according to claim 1, wherein the resin coating layer contains conductive fine powder. 5. The developer carrying member according to claim 1, wherein the resin coating layer contains a lubricating substance. 6. A development in which a developer is supported on a latent image carrier while the developer is carried on the developer carrier and a thin layer of the developer is formed by a developer layer regulating member. In a developing device which conveys a developer to a latent image formed on a latent image carrier, the developer carrier is a spherical resin whose surface is modified by fine particle resin particles. A developing device, wherein a resin coating layer containing particles is formed on the surface of a metal cylinder. 7. The spherical resin particles have a particle size of 0.3 to 30 μm.
7. The developing device according to claim 6, wherein the resin particles having a fine particle diameter have a particle diameter ratio of 0.2 or less with respect to the resin particles. 8. The developing device according to claim 6, wherein the fine resin particles are made of a resin having a low surface energy. 9. The developing device according to claim 6, wherein the resin coating layer contains conductive fine powder. 10. The developing device according to claim 6, wherein the resin coating layer contains a lubricating substance.