WO1990016017A1 - Developing apparatus - Google Patents

Developing apparatus Download PDF

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Publication number
WO1990016017A1
WO1990016017A1 PCT/JP1990/000808 JP9000808W WO9016017A1 WO 1990016017 A1 WO1990016017 A1 WO 1990016017A1 JP 9000808 W JP9000808 W JP 9000808W WO 9016017 A1 WO9016017 A1 WO 9016017A1
Authority
WO
WIPO (PCT)
Prior art keywords
magnetic
magnetic roller
developing device
developer
roller
Prior art date
Application number
PCT/JP1990/000808
Other languages
French (fr)
Japanese (ja)
Inventor
Yoshiro Koga
Tahei Ishiwatari
Takashi Hama
Original Assignee
Seiko Epson Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP15891989A external-priority patent/JPH0324574A/en
Priority claimed from JP17233389A external-priority patent/JPH0336574A/en
Priority claimed from JP17233989A external-priority patent/JPH0337689A/en
Priority claimed from JP17233589A external-priority patent/JPH0336571A/en
Priority claimed from JP17233489A external-priority patent/JPH0336575A/en
Priority claimed from JP17233789A external-priority patent/JPH0336573A/en
Priority claimed from JP17233689A external-priority patent/JPH0336572A/en
Priority claimed from JP17233889A external-priority patent/JPH0337690A/en
Priority claimed from JP17952289A external-priority patent/JPH0344674A/en
Priority claimed from JP17950789A external-priority patent/JPH0343766A/en
Priority claimed from JP17952189A external-priority patent/JPH0344673A/en
Application filed by Seiko Epson Corporation filed Critical Seiko Epson Corporation
Publication of WO1990016017A1 publication Critical patent/WO1990016017A1/en

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Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/09—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer using magnetic brush
    • G03G15/0921—Details concerning the magnetic brush roller structure, e.g. magnet configuration
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/02—Permanent magnets [PM]
    • H01F7/0231—Magnetic circuits with PM for power or force generation
    • H01F7/0252—PM holding devices
    • H01F7/0268—Magnetic cylinders

Definitions

  • the present invention relates to an image recording apparatus using an electrophotographic process, and more particularly, to a developing device for developing an electrostatic latent image pattern formed on a latent image carrier.
  • a magnetic brush developing device As is known as a magnetic brush developing device (one-component magnetic brush and two-component magnetic brush), a rotatable non-magnetic and conductive cylinder represented by stainless steel, aluminum or brass is used.
  • a cylindrical developer roller also referred to as a developing sleeve
  • the developer is held on the developer conveying member in accordance with the magnetic field generated by the magnetic roller, and at least one of the magnetic material port and the developer conveying member is used.
  • the mainstream is to rotate one side to transport the developer on the developer transport member.
  • the outer diameter of the magnetic roller is polished to obtain the outer diameter accuracy, and the magnetic roller and the developer conveying member are accurately arranged with a small gap therebetween. Therefore, the number of man-hours and cost have been increased, and the outer diameter of not only the magnetic roller but also the developer conveying member has been required, thus making the developing device more expensive. In addition, the number of components that support the magnetic roller and the developer conveying member ⁇ ⁇ ⁇ ⁇ and the components associated therewith are increased, which has hindered the reduction in size and weight of the developing device.
  • the number of magnetized poles of the magnetic roller is increased, the number of magnetized poles of the magnetic roller is sufficient to reduce unevenness in development density due to the magnetic pole pitch of the magnetic roller, which is unique to the image obtained when the magnetic roller is rotated. As a result, a large amount of magnetic flux could not be secured, which hindered the transport of the developer.
  • the present invention solves such a problem.
  • the purpose of the present invention is to provide a developing device structure that transports the developer directly on the surface of the magnetic roller, thereby making it possible to cover all processes from manufacturing to assembly.
  • the aim is to provide a low-cost developing device with less man-hours.
  • Still another object is to provide a small and lightweight developing device.
  • It is still another object of the present invention to provide a developing device capable of effectively utilizing a magnetic field generated by a magnetic roller, securing a sufficient amount of developer to be conveyed, and obtaining a high-concentration developing density.
  • It is still another object of the present invention to provide an imaging apparatus capable of reducing unevenness in development density by a magnetic roller and obtaining high printing quality.
  • the developing device of the present invention uses the electrophotographic process.
  • a developing device for developing an electrostatic latent image pattern formed on the latent image carrier in the image recording apparatus comprising a cylindrical magnetic roller formed by magnetizing a plurality of magnetic poles.
  • the developer is directly supplied onto the body roller to hold the developer on the surface of the magnetic roller by a magnetic field generated by the magnetic roller, and the magnetic roller is rotated to remove the carried developer. It is characterized by being transported.
  • a developing device having a simple structure can be configured by omitting the developer conveying member (sleeve) conventionally disposed on the outer peripheral side of the magnetic roller. Also, since the developer is directly transported by the magnetic roller, the magnetic field generated by the magnetic roller (magnet) can be used most effectively. Furthermore, a magnetic roller made of a rare-earth magnet with high magnetic properties can be used to form a compact and lightweight magnetic roller. The magnet is formed by injection molding, compression molding, or extrusion molding. A magnetic roller having excellent accuracy and requiring no post-processing can be configured. Particularly, the mechanical strength and magnetic properties can be improved by incorporating a yoke made of a magnetic material constituting a magnetic circuit into the inside of the magnetic roller. Other features of the present invention will become apparent from the following description.
  • FIG. 1, FIG. 4 and FIG. FIG. 2 is a diagram illustrating an outline of the device
  • FIG. 2 is a schematic cross-sectional view of a magnetic roller provided in the developing device.
  • FIG. 3 is a schematic cross-sectional view illustrating a state in which the developer is held on the surface of the magnetic roller.
  • FIG. 6A and FIG. 6B are diagrams each showing an applied state of an alternating voltage.
  • FIG. 1 is a schematic cross-sectional view of an image forming apparatus including a developing device according to a specific embodiment of the present invention.
  • the latent image carrier 1 is formed by forming a photosensitive member 3 made of an organic or inorganic photoconductive material on a conductive supporting portion 2. After the photosensitive member 3 is charged using a charger 4 such as a corona charger, light emitted from a light source 5 is selectively applied to the photosensitive layer 3 by an imaging optical system 6 according to an image. Irradiation is performed to obtain a potential contrast on the photosensitive layer 3 to form a desired electrostatic image pattern.
  • a charger 4 such as a corona charger
  • a developing device 7 charges a developer 8 which is an image forming body, and conveys the developer by a cylindrical magnetic roller 9 so that the latent image carrier 1 and the magnetic roller 9 are close to each other.
  • the developer 8 is developed according to the potential potential of the electrostatic latent image on the latent image carrier 1 and the bias voltage by the developing bias voltage applying means 10.
  • the developer 8 that visualizes the electrostatic latent image is transferred to a recording paper 15 by a transfer unit 14 using corona discharge, electric field, pressure, or adhesive force, and the developer 8 is pressed or heated. Is fixed on the recording paper 15 to obtain a desired image by the developer 8 on the recording paper 15.
  • the magnetic roller 9 conveys the developer 8 while holding the supplied developer 8 by a magnetic force while regulating the transport amount regulating member 11 to an appropriate amount.
  • the magnetic roller 9 can form a magnetic circuit with a magnet 12 having a plurality of cylindrical outer circumferences and poles magnetized and a cylindrical yoke 13 made of a diamagnetic material.
  • the handling such as installation and removal of the magnetic roller becomes extremely easy.
  • the inertia moment of the magnetic material is small, so the rotation rises quickly, and when rotating at low speed, rotating at high speed. It has an excellent effect that there is almost no rotation unevenness during rotation and the torque required for rotation is small. That is, the interior of the magnetic roller 9 is hollow and has a small amount of elasticity.
  • the magnetic roller 9 is rotated, the rotation rises quickly, and uneven rotation occurs at low speed and high speed. There is almost no need for the torque required for rotation, and the developer can be supplied stably without excess or shortage. Therefore, high print quality can be obtained by reducing unevenness in the development density.
  • FIG. 2 is a schematic view of a magnetic roller of a developing device according to another embodiment of the present invention.
  • the developer is held and transported according to the magnetic field distribution on the outer peripheral surface of a magnet 12 composed of a cylindrical rare earth magnet magnetized in a plurality of poles in the radial direction.
  • the magnetic roller 9 is mainly composed of iron or the like.
  • a magnetic circuit is constructed by arranging a magnetic yoke 13 on the inner peripheral side of the magnet 12 by bonding or the like.
  • the magnet 22 can be made thin by forming the magnet 22 from a rare earth magnet. By magnetizing the number of magnetic poles to 10 or more, the weight of the yoke 13 can be reduced.
  • the yoke 13 made of a magnetic material is placed in a molding die before molding the magnet, and a magnet material containing magnetic powder, resin, or the like is injection-molded on the outer periphery of the yoke 13 so that the magnet 12 and the magnet 13 are joined together.
  • the magnetic material roller 9 can be formed by integrally molding the magnetic material roller 13 and the magnetic material roller 13. According to such a method, integral molding can be easily performed by plastic injection molding, and the thickness of the magnet can be reduced.
  • the run-out of the outer diameter portion of the magnetic roller 19 can be reduced to 25 m or less, whereby the fluctuation of the amount of transported developer and the fluctuation of the developing gap can be reduced.
  • all developers known as a one-component magnetic brush developer and a two-component magnetic brush developer can be applied.
  • magnet material of the magnetic roller used in the present invention known magnet materials such as a fluoride magnet, an alnico magnet, a manganese aluminum magnet, and a rare earth magnet can be used.
  • rare earth elements such as C e force with atomic number 58 and Lu of 71, among them, rare earth elements represented by Nd, Pr and Sm, Fe, Ni and C
  • a rare-earth magnet to which a 3d transition metal, typified by o, is added as the magnet 22 a high magnetic field can be obtained even with a thin wall, and therefore a compact and lightweight magnetic roller can be constructed. I can do it.
  • a molded magnet using a manufacturing method such as compression molding, injection molding, or extrusion molding can be used. High degree of freedom of magnetic field distribution I can do it.
  • the yoke, etc., constituting the magnetic circuit can be integrally formed at the time of molding, and the deflection of the outer diameter can be reduced to 25 urn or less without post-processing. Accuracy can be improved. In addition, since complicated means such as bonding are not used, the variation in the magnetic resistance of the magnetic circuit is small, and the magnetic flux density on the magnet surface is equalized. Can be reduced. Further, since the thickness of the magnet can be reduced, even with a magnet having an outer diameter of about 2 OBB, a magnetized yoke can be arranged inside and outside to easily perform multipole magnetization of 10 or more poles. Therefore, multi-pole magnetization is performed at a magnetization pitch about the same as the thickness of the magnet, whereby fluctuations in the amount of developer transported and fluctuations in the amount of development can be reduced.
  • a magnetic roller is composed of a 2 OM outer diameter, 4 OT thickness, 4 OT, and a yoke with an outer diameter of 1 2 na, thickness of 2 na, which constitutes a magnetic circuit inside.
  • a magnetic flux density 1000 gauss or more was obtained on the magnet surface, and a sufficient amount of developer and a sufficient transport amount were obtained.
  • the magnetic roller is The weight can be reduced by the metal sleeve, which is a conventional developer conveying member.
  • a samarium-cobalt-based compression-molded magnet with an outer diameter of 20 Ba and a thickness of 1.5 mil and an outer diameter of 17 ma with an outer diameter of 17 ma that constitutes a magnetic circuit inside
  • a magnetic roller is composed of the yoke and the magnet is divided and magnetized into 40 poles.As a result, a magnetic flux density of 100 gauss or more is obtained on the magnet surface, and a sufficient amount of developer spikes and transport amount can be obtained.
  • the weight of the magnetic roller has been reduced to less than half that of the conventional roller using a magnet and a metal sleeve.
  • Fig. 1 shows a developing device as shown in Fig. 1 with an injection-molded magnet made of samarium-cobalt with an outer diameter of 12M and a thickness of 1ma and a yoke with an outer diameter of 10M and a wall thickness of 1ma that forms a magnetic circuit inside.
  • the magnetic roller is formed integrally and the magnet is divided and magnetized into 40 poles, a magnetic flux density of 100 gauss or more is obtained on the magnet surface, and a sufficient amount of developer pan and transport amount are obtained.
  • the weight of the magnetic roller was reduced to less than one-fourth that of the conventional roller using a magnet and a metal sleeve.
  • a developing device as shown in Fig. 1 is composed of a brassiodium-based extruded magnet with an outer diameter of 20 M and a thickness of Inn and a yoke with an outer diameter of 18 ma and an IBB with a thickness of BB constituting a magnetic circuit inside.
  • a magnetic roller is configured and the magnet is divided and magnetized into 60 poles, a magnetic flux density of 100 gauss or more can be obtained on the magnet surface, and a sufficiently thin layer of developer can be obtained with the conveyed amount of developer.
  • the weight of the magnetic roller was reduced to less than half that of the conventional roller using a magnet and a metal sleeve.
  • Example A 5 when an image was formed using this developing device, when the magnetic roller was moved at a linear velocity higher than the linear velocity of the latent image carrier, unevenness in development density became almost indistinguishable by visual observation, and high density As a result, a high-contrast image could be formed stably.
  • Example A 5 when the magnetic roller was moved at a linear velocity higher than the linear velocity of the latent image carrier, unevenness in development density became almost indistinguishable by visual observation, and high density As a result, a high-contrast image could be formed stably.
  • a magnetic roller is composed of a 1 BB resin-bound fused magnet and an outer diameter of 18 M thick I BH yoke that constitutes a magnetic circuit inside, and the magnet is divided into 60 poles and magnetized. At this time, a magnetic flux density of 200 gauss or more was obtained on the magnet surface, and a thin layer of the developer and the transport amount were obtained. Also, the weight of the magnetic roller was reduced to less than half that of the conventional one using a ferrite magnet and a metal sleeve. Furthermore, when an image was formed using this developing device, when the magnetic roller was moved at a linear velocity higher than the linear velocity of the latent image carrier, unevenness in the development density became almost indistinguishable by visual observation. High-contrast images could be stably formed at a high temperature.
  • the conventional one-component magnetic developing device uses a developer transporting member (non-magnetic metal sleeve) with a diameter of 20 M, and a magnetic roller disposed inside the roller.
  • a developer transporting member non-magnetic metal sleeve
  • a magnetic roller disposed inside the roller.
  • a developer roller with an outer diameter of 20 iw was used, and a magnetic roller provided inside was cut to an outer diameter of 18 Ba and a wall thickness of 5 mm.
  • the magnet is composed of fluite magnet
  • the magnetic roller is divided into 8 poles or less, and if it is magnetized, a magnetic flux density of 500 gauss or more can be obtained on the surface of the developer transfer member, and sufficient developer spikes and transfer amount can be obtained. I got it.
  • the weight of the magnetic roller was not less than 0.4 kg with a length of 22 ⁇ , which could not be reduced.
  • the present invention is not limited to the above embodiments, and can be widely applied to developing devices such as electrophotography, especially if applied to printers and copiers, such as facsimile machines and displays. It is valid.
  • the man-hour from manufacturing to assembly is reduced.
  • a cost developing device can be provided.
  • a small and lightweight developing device can be provided.
  • the developer is transported by the magnetic flux leaking from the surface of the magnetic material, the magnetic field generated by the magnetic roller is effectively used to secure a sufficient amount of developer transport to obtain a high-density development density.
  • Developing device that can be provided, and the developer can be retained even if the magnet is magnetized to multiple poles. It is possible to provide a developing device that has sufficient magnetic properties for carrying and transporting, reduces development density unevenness due to the magnetic roller, and obtains high printing quality.
  • the magnet of the magnetic roller by using a rare earth magnet as the magnet of the magnetic roller, it is possible to provide a developing device capable of obtaining a magnetic field sufficient to hold and transport the developer even when the thickness of the magnet is reduced, As a result, the amount of magnetic powder in the developer can be reduced. Furthermore, even if the fixing temperature is lowered, excellent fixing characteristics can be obtained, and an image with excellent surface gloss can be formed.
  • the molded magnet as the magnet of the magnetic roller, an efficient magnetic circuit with less processing and assembling man-hours, good dimensional accuracy, and low magnetic resistance can be formed.
  • the magnet has a magnetic aperture with a magnetic yoke inside the magnet to form an efficient magnetic circuit, and a magnetic flux sufficient to hold and transport the developer on the surface of the magnetic roller. Can be obtained.
  • a magnetic roller having a small number of processing and assembling steps, good dimensional accuracy, and excellent moldability even with a thin wall can be obtained.
  • a magnetic flux sufficient to hold and transport the developer on the surface of the magnetic roller can be obtained.
  • the developing device S which is small, lightweight, inexpensive and can form an image with high image quality.
  • the intermediate portion (boundary portion) of the NS pole so as to be convex.
  • the outer diameter of the magnetic brush formed by the developer 8 can be made uniform regardless of the position of the magnetic pole.
  • the height of the peaks of the uneven shape is about half the thickness of the developer to be formed, a good uniformizing effect can be obtained.
  • the above-mentioned uneven shape has the following relationship.
  • the magnetic roller is magnetized to a plurality of magnetic poles only in the circumferential direction.
  • the magnetic roller is magnetized to multiple magnetic poles only in the axial direction, the same number of irregularities as the number of magnetic poles are formed in the axial direction.
  • the uneven shape depends on the number of magnetized waves
  • the outer diameter of the magnetic brush can be made uniform by forming a concave or convex shape in an arc shape or a sine wave shape.
  • the radius of rotation of the tip of the developer is kept constant regardless of the magnetic pole position, and in the case of contact development, the width of the development nip is reduced. It is possible to obtain a stable image portability by keeping the temperature constant during development and the magnetic scraping force constant.In the case of non-contact development, it is possible to maintain a stable development field and obtain a stable image portability. it can. Also, by using the above-described compression molding, injection molding, extrusion molding, or the like, a predetermined uneven shape can be easily formed on the surface of the magnetic roller.
  • a resin vial having an outer diameter of 20 ai «, a thickness of a convex portion of 1 Bn, a thickness of a concave portion of 0.85 M, and a number of concave portions and convex portions of 60 each is used.
  • Ferrite magnets and the 6 A magnetic roller is composed of an outer diameter of 18 and a yoke with a wall thickness of 1 ma that partially constitute a magnetic circuit.When the magnet is divided into 60 poles and magnetized, the magnet surface has more than 200 gauss. A magnetic roller having a high magnetic flux density and a thin layer of developer having a uniform outer diameter of the ear was obtained.
  • the weight of the magnetic roller was reduced to less than half that of a conventional roller using a fumed magnet and a metal sleeve. Further, when an image was formed using this developing apparatus, unevenness in the developing density was hardly visually discerned, and a high-density, high-contrast image could be formed stably.
  • a magnetic roller is composed of an outer diameter of 17 M and an IOT yoke that forms a magnetic circuit inside the magnet, the magnet is divided into 40 poles and magnetized.
  • the weight of the magnetic roller was reduced to less than half that of the conventional roller using a magnet and a metal sleeve.
  • unevenness in the developing density was almost indistinguishable by visual observation, and an image with high density and high contrast was stably formed.
  • a developing device as shown in Fig. 1 has an outer diameter of 12 mm, a thickness of 1 IDB, a concave wall thickness of 0.9 IM, and a number of irregularities of 40.
  • a magnetic roller is integrally formed with a yoke with an outer diameter of 10 M and a wall thickness of 1 aW that constitutes the circuit.When the magnet is divided into 40 poles and magnetized, it is more than 1000 Gauss on the magnet surface. A magnetic roller with a constant outer diameter of the spike of the imaging agent was obtained. Also, the weight of the magnetic roller was reduced to one-fourth or less than that of a conventional magnet using a magnet and a metal sleeve. Further, when an image was formed using this developing apparatus, unevenness in the developing density was hardly visually discerned, and an image having a high density and a high contrast could be stably formed.
  • a conventional one-component magnetic developing device that uses a developer transport member (non-magnetic metal sleeve) with an outer diameter of 2 O IDII, and uses a magnetic roller placed inside the outer diameter of 18 M thick 2 B
  • a developer transport member non-magnetic metal sleeve
  • O IDII non-magnetic metal sleeve
  • a magnetic roller placed inside the outer diameter of 18 M thick 2 B
  • a conventional one-component magnetic developing device that uses a developer transport member with an outer diameter of 20 OT and cuts a magnetic roller disposed inside it into an outer diameter of 18 OT and a thickness of 5 OT, and sintered sintered magnet.
  • the magnetic roller was divided into 8 poles or less and magnetized, a magnetic flux density of more than 500 gauss was obtained on the surface of the developer transfer member, and sufficient developer spikes and transfer amount were obtained.
  • the weight of the magnetic mouthpiece was 0.4 kg or more at a length of 220 M, and the weight could not be reduced, and the unevenness in concentration due to the change in the magnetic field was remarkable.
  • the surface roughness of the magnetic roller is defined as a 10-point average roughness (JIS-B0601) of JIS standard.
  • JIS-B0601 10-point average roughness
  • the magnetic material roller and the developer transport amount regulating member are When the toner passes between the toner particles, the pressure and frictional force applied to the contact portion between the toner and the magnetic material roller are reduced, and as a result, deterioration of the toner on the magnetic material roller, the toner, or the toner is reduced. Is estimated to be suppressed.
  • the above-described filming prevention effect is poor. Note that the above-described surface roughness control can be similarly applied to a magnetic roller having irregularities as described above.o
  • carbon black click, F e 3 0 4 the volume average particle Kai 1 O to a polyester resin as a main component; using one-component developer according to the magnetic toner of the m 0 "developing device of the structure JIS standard 10 point average roughness (JIS-B0601)
  • the surface roughness of each roller is different (in the range of l to 10 / zm).
  • JIS standard 10 The image obtained when the surface roughness based on the 10-point average roughness is greater than 4 // m clearly shows brushing and ground covering, and the magnetic roller 9 clearly shows filming with toner.
  • the image obtained when the surface roughness of the magnetic material roller 9 according to the JIS rating 10-point average roughness was 4 iim or less was a good image with no brushing or ground covering, and No fining by the toner was observed on the magnetic roller 9.
  • the volume average particle diameter of the toner used in this embodiment is lO m0, when the surface roughness of the magnetic roller 9 according to the JIS standard 10-point average roughness is 4 wm or less, that is, the magnetic material A good image can be obtained when the surface roughness of the roller 9 according to the JIS 10 point average roughness is 40% or less of the volume average diameter of the toner.
  • a developer was used.
  • the image forming apparatus conforms to JIS standard 10-point average roughness (JIS-B0601).
  • JIS-B0601 JIS standard 10-point average roughness
  • images of 500,000 sheets of A4 size plain paper were continuously formed, and the average of JIS standard 10 points of the magnetic roller 9 was obtained.
  • the image obtained when the surface roughness due to the roughness was greater than 4.8 ⁇ m showed brushing and ground covering, and the magnetic material aperture 9 showed toner filming
  • the volume average particle diameter of the toner used in this example is the volume average particle diameter of the toner used in this example.
  • the image forming apparatus is based on JIS standard 10 point average roughness (JIS-B0601).
  • JIS-B0601 JIS standard 10 point average roughness
  • images of 50,000 sheets of A4 size plain paper were continuously formed, and the surface roughness of the magnetic roller 9 according to the JIS standard 10-point average roughness was obtained.
  • the image obtained when the height was larger than 3.6 m stitches and ground covering were clearly observed in the image of the magnetic material opening 9, and filming with toner was clearly observed in the magnetic opening 9.
  • the image obtained when the surface roughness according to JIS standard 10-point average roughness is 3.6 or less is a good image with no brushing or ground covering, and the magnetic material aperture 9 No filming with toner was observed.
  • the magnetic roller 9 Since the volume average diameter of the toner used in the present embodiment is 9, the magnetic roller 9 has a surface roughness of 3.6 m or less according to the JIS standard 10-point average roughness, that is, the magnetic property. A good image can be obtained when the surface roughness of the body roller 9 according to JIS 10 point average roughness is 40% or less of the volume average particle size of the toner.
  • known magnetic materials such as ferrite, alnico, manganese aluminum, and rare earth magnets can be used as the magnetic material for the magnetic roller, and in particular, atomic numbers 58 to 71 (element symbol C e ⁇ Lu), at least one of the rare earth elements represented by Nd, Pr and Sm, Fe, Ni and It is desirable to use a rare earth magnet to which at least one of the 3d transition metals represented by Co is added.
  • oxidative corrosion occurs on the surface of the magnetic roller due to the influence of oxygen or moisture in the air.
  • a rare earth magnet is used by providing a coating layer on the surface of the magnetic roller (at least being coated so that the magnet is not exposed on the developer transport surface of the magnetic roller). In this case, oxidative corrosion does not occur on the surface of the magnetic roller due to the influence of oxygen or moisture in the air, so that a high-quality image can be stably formed for a long period of time.
  • any material can be used as long as it can cover the surface of the magnetic roller 9 so that the magnets 12 are not exposed. , Ni, Au, Pt, etc.
  • the thickness of the coating layer is determined to prevent the occurrence of defects such as via holes during the formation of the coating layer and to prevent the coating layer from being used for a long time.
  • Example Dl From the viewpoint of preventing layer deterioration, a thickness of 1 m or more is desirable.
  • a neodymium iron-based sintered magnet was used as the magnetic roller 9, and the surface of the magnetic roller 9 was coated with an epoxy resin as a coating layer.
  • an image corresponding to 500,000 sheets of A4 size plain paper was continuously formed under an environment of a temperature of 30 and a relative humidity of 60%.
  • no deterioration of the obtained image was observed, and a high-resolution, high-quality image was obtained as in the case of the first printed sheet.
  • No oxidative corrosion was observed on the surface of the magnetic material roller 9, and a developer layer having a uniform thickness was formed stably on the magnetic material roller 19.
  • Example D 2 An image forming apparatus using a developing device having the same configuration as that of Example D1 except that the surface of the magnetic roller 9 was not covered with the epoxy resin and the magnets 12 were exposed, was used in the same manner as in Example D1.
  • an image equivalent to 500 000 sheets of A4 size plain paper was continuously formed under the environment, the obtained image showed blurring such as brushes and deterioration of ground covering, etc. Oxidation corrosion was observed on the surface of body roller 9, Example D 2
  • a neodymium-iron sintered magnet is used as the magnetic roller 9, and a magnetic material is used as the coating layer.
  • the surface of the roller 9 was covered with Ni (Ni plating).
  • A4 size plain paper was used in the same environment as in Example D1.
  • Example D1 was repeated using an image forming apparatus having a configuration similar to that of Example D2 except that the magnet 12 was exposed without covering the surface of the magnetic roller 9 with Ni. Under the same environment, when an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, the obtained image showed blurring of brush eyes and deterioration of ground covering, etc. Oxidation corrosion was observed on the surface of the magnetic roller 9.
  • a neodymium-iron sintered magnet was used as the magnetic roller 9, and the surface of the magnetic roller 9 was coated with SiO 2 as a coating.
  • Example D 1 The surface of the magnetic roller 9 by using the image forming apparatus according to the developing apparatus having the same construction as in Example D 3 except that the magnet 1 2 without ⁇ S by S i 0 2 is exposed, Example D 1 Under the same environment as above, A4 size plain paper 50,000 sheets, and the corresponding images were formed by continuous shooting. The resulting images showed blurring such as brushing and deterioration of ground covering. Oxidation corrosion was observed on the surface of the magnetic roller 9.
  • Example D1 using the neodymium ⁇ -time iron-based sintered magnet as magnetic roller 9, the surface of the magnetic roller 9 was ⁇ covered by T i 0 2 as further coated ⁇ .
  • A4 size plain paper was used in the same environment as in Example D1.
  • Example D 1 Except that the magnet surface of the magnetic roller 9 uncovered by T i 0 2 is exposed with an image forming apparatus according to the current image device having the same structure as in Example D 4, as in Example D 1 In this environment, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, and the obtained image showed blurring of brush eyes and deterioration of ground covering, etc. Oxidative corrosion was observed on the surface of body ro-1-9.
  • Example D1 was performed using an image forming apparatus using a developing device having the same configuration as that of Example D5 except that the magnet 12 was exposed without covering the surface of the magnetic roller 9 with SiC. Same as Under the same environment, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, and the resulting image showed blurring such as brushing and deterioration of ground covering. However, oxidation corrosion was observed on the surface of the magnetic roller 9.
  • Purase Ojiumu the iron-based ⁇ magnet used as the magnetic body roller 9
  • the surface of the magnetic material element Ronira 9 has a structure covered by A 1 2 0 3 as a further object S employment.
  • A4 size plain paper was produced under the same environment as in Example D1.
  • the surface of the magnetic roller 9 by using the image forming apparatus according to the developing apparatus is similar configurations to Example D 6 except that exposed magnet 1 2 uncovered by A 1 0 3, Example D 1 Under the same environment as above, when images equivalent to 500,000 sheets of A4 size plain paper were continuously formed, the obtained images showed blurring such as brushes and deterioration of ground covering, etc., and Oxidation corrosion was observed on the surface of the magnetic roller 9.
  • Example D 7
  • a magnetic material roller 9 is made of a plastic magnet, and an iron-based artificial magnet is used, and the magnetic material roller 9 is coated with ⁇ as a coating.
  • A4 size plain paper in the same environment as in Example D 1 using a forming apparatus is made of a plastic magnet, and an iron-based artificial magnet is used, and the magnetic material roller 9 is coated with ⁇ as a coating.
  • Example D1 was performed using an image forming apparatus using a developing device having the same configuration as that of Example D7 except that the magnet 12 was exposed without covering the surface of the magnetic material roller 9 with Zn0. Under the same environment as above, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, and the resulting image showed blurring such as brushing and deterioration of ground covering. Oxidation corrosion was observed on the surface of the magnetic roller 9.
  • a magnetic roller 9 is made of extruded magnet made of a place iron or an iron-based magnet, and the surface of the magnetic opening 9 is coated with A 1 as a coating. did.
  • Example D1 Using an image forming apparatus including the developing device having the above-described configuration, A4 size plain paper under the same environment as in Example D1.
  • Example D8 Using the image forming apparatus having the same configuration as in Example D8 except that the magnet 12 is exposed without covering the surface of the magnetic roller 9 with A1, Under the same environment, when an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, the obtained image showed blurring of brush eyes and deterioration of ground covering, etc. Oxidation corrosion was observed on the surface of the magnetic roller 9.
  • a magnet and a cobalt-based extruded magnet were used as the magnetic roller 19, and the surface of the magnetic roller 9 was coated with Ni as a coating layer.
  • Example D1 Using an image forming apparatus including the developing device having the above-described configuration, A4 size plain paper under the same environment as in Example D1.
  • Example D1 was performed using an image forming apparatus having a configuration similar to that of Example D9 except that the magnet 12 was exposed without covering the surface of the magnetic roller 9 with Ni. Under the same environment, when images of A4 size plain paper 500 000 sheets were continuously formed, the obtained images showed blurring such as brush eyes and deterioration of ground covering, etc. However, oxidation corrosion was observed on the surface of the magnetic roller 9.
  • Example D1 Using an image forming apparatus including the developing device having the above-described configuration, A4 size plain paper under the same environment as in Example D1.
  • Example D 1 Except that the magnet 1 2 is exposed without the surface of the magnetic roller 9 was coated with T i 0 2 by using the image forming instrumentation g by the developing apparatus having the same configuration as in Example D 1 0, Example Under the same environment as D1, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, and the resulting image showed blurring such as brushing and deterioration of ground covering. Oxidation corrosion was observed on the surface of the magnetic roller 9.
  • a direct transport type developing device such as the present invention
  • frictional charging between the surface of the magnetic roller and the developer frictional charging between the developer and the developer, developer transport amount regulating member, etc. Due to various charging mechanisms such as frictional charging between the components of the developing device and the developer, the amount of charge of each developer greatly differs. Due to such a difference in the charging mechanism, the developer having a broad charge amount distribution is conveyed onto the magnetic roller and the resulting image has a very low image quality. There is a possibility that.
  • the above problem can be solved by providing a coating layer made of at least one kind of resin on the surface of the magnetic roller. That is, the coated resin layer acts on the developer conveyed on the magnetic roller as if it were a carrier that is a component of a two-component developer.
  • this action makes the distribution of the charging amount of the developer uniform, and as a result, a high-quality image can be stably formed.
  • the S layer contains a resin containing at least one of fluorine and silicon, filming (fixing or fusing) of the developer on the surface of the magnetic roller is prevented.
  • the surface of the magnetic roller can be stably and cleanly maintained for a long period of time, so that a high-quality image can be stably formed for a long period of time.
  • the coating layer (resin layer) completely or uniformly covers the surface of the magnetic roller 9 .
  • the coating thickness may be non-uniform, or the coating may be incomplete, exposing the magnet (the surface of the magnetic roller).
  • the coating is not continuous, and many resin islands are formed independently. It may be ⁇ formed on the surface of the magnetic roller 9.
  • any known developer can be used as the one-component magnetic brush developer and the two-component magnetic brush developer, and the resin constituting the coating layer is appropriately selected. Accordingly, it is possible to control the charged polarity of the developer 8 to a desired polarity regardless of the polarity of the positive electrode or the negative electrode.
  • the resin constituting the coating In order to control the chargeability of the developer 8 by using the S layer, it is important to select the resin constituting the coating as described above.
  • the resin constituting the developer 8 In the process using the developer, when the charge control agent is mixed in the developer 8, in order to maximize the charging effect of the charge control agent, the resin constituting the developer 8 and the resin It is desirable to use an equivalent resin, and when a charging agent is mixed in the developing agent 8, but sufficient charging cannot be obtained or charging is insufficient under the charging control agent, the developing agent 8 is used. It is desirable to use a charging series of resin that reinforces or suppresses the charging effect of the dyden control agent on the resin constituting the resin, and the present invention is particularly effective when charging is performed during image formation.
  • a sintered sintered magnet was used as the magnetic roller 9 and (a large number of independent) island-shaped covering members made of a polyester resin were formed as the covering flex (resin scoop).
  • an image equivalent to 500 sheets of A4 size plain paper is continuously formed.
  • the obtained image was a high-resolution, high-robustness and high-quality image, similar to the first printed sheet.
  • An image was continuously formed under the same conditions using an image forming apparatus having a developing device having the same configuration as that of Example E1 except that the surface of the magnetic roller 9 was not covered. At this time, the obtained image was a low-quality image with low image intensity and uneven density.
  • a summary cobalt-based extruded magnet was used as the magnetic roller 19, and a (many independent) island-like coating layer made of polycarbonate resin was formed as the coating.
  • Example E 3 An image was continuously formed under the same conditions using an image forming apparatus having the same configuration as that of Example E2 except that the surface of the magnetic material roller 9 had no coating layer. The obtained image was a low-quality image with low image density and uneven density.
  • Example E 3 An image was continuously formed under the same conditions using an image forming apparatus having the same configuration as that of Example E2 except that the surface of the magnetic material roller 9 had no coating layer. The obtained image was a low-quality image with low image density and uneven density.
  • a neodymium-iron sintered magnet was used as the magnetic roller 9, and a uniform (non-exposed magnet) coating layer was formed with polyimide resin as the coating layer.
  • images equivalent to 500 sheets of A4 size plain paper were continuously formed, but the obtained image was as high as the first sheet of printing. High quality images with high resolution and high port were obtained.
  • An image was continuously formed under the same conditions using an image forming apparatus using a developing device having the same configuration as that of Example E3 except that there was no coating layer on the surface of the magnetic roller 9.
  • the obtained image was a low-quality image with low image density and uneven density.
  • a neodymium-iron sintered magnet is used as the magnetic roller 9, and a uniform (non-exposed magnet) coating layer is formed with silicone resin (organic silane resin) as the coating layer. did.
  • an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, but the obtained image has a high resolution similar to the first print.
  • a high quality image was obtained at a high port degree.
  • filming with the developer was observed on the surface of the magnetic roller 9. Did not.
  • Example E4 An image was continuously formed in the same manner as in Example E4 by using an image forming apparatus with a developing device having the same configuration as that of Comparative Example E3. From the time when images corresponding to the size of 30000 sheets of plain paper were successively formed, the obtained images were low-quality images in which blurring such as brush lines was observed. In addition, filming by the developer was observed on the surface of the magnetic roller 9.
  • a uniform coating layer (without exposure of the magnet) was formed with a polyurethane resin as a coating layer by using a plastic ⁇ iron-based magnet as the magnetic roller 9.
  • an image forming apparatus including the developing device having the above-described configuration, an image corresponding to 500 sheets of A4 size plain paper was continuously formed, but the obtained image had a high resolution and the same as the first print. A high-density and high-quality image was obtained.
  • a neodymium-iron sintered magnet is used as the magnetic roller 9, and the coating is made uniform (no magnet is exposed) by a polyurethane resin in which tetrafluorocarbon titanium resin particles are dispersed. A coating ⁇ was formed.
  • An image equivalent to 500 sheets of A4 size plain paper was formed at an accelerated rate using an image forming apparatus with the developing device having the above-described configuration. High-quality images with high resolution and high density were obtained. Also, no filming by the developer was observed on the surface of the magnetic material row 9.
  • Example E6 When an image was continuously formed in the same manner as in Example E6 using an image forming apparatus with a developing device having the same configuration as that of Comparative Example E5, the obtained image had a low image density, and furthermore A Since an image equivalent to three-hundred and four sheets of plain paper of four sizes was continuously formed, the obtained image was a low-quality image in which blurring such as brush lines was observed. Further, filming by the developer was observed on the surface of the magnetic roller 9.
  • a known magnet material such as ferrite, alnico, manganese aluminum, and rare earth magnet can be used as the magnet material of the magnetic roller.
  • high-resistance materials such as When the developer is used as the magnetic roller, a developing bias voltage is applied to the developer conveyed on the magnetic roller during development, or an electrostatic latent image on the latent image carrier is formed.
  • a so-called developing electrode for enhancing the electric field formed by the potential bond is separately installed, or a conductive member such as a yoke or a shaft installed inside the magnetic roller is used as a developing electrode.
  • the developing electrode is installed at a position away from the latent image carrier and the developer.
  • a high resistance material such as a fluoride magnet is also applied to the magnetic roller.
  • the imaging electrode must be installed separately In some cases, the structure may be complicated, or the developing electrode may be located away from the latent image carrier or the developer, causing problems such as a reduction in resolution and an increase in energy consumption.
  • the above-mentioned problems can be prevented by providing an S layer made of at least one kind of conductive material on the surface of the magnetic roller. That is, since the conductive material layer functions as a developing electrode, a high-quality image can be stably formed for a long period of time.
  • the developing device 7 discharges the developer 8 as a component of the developer, and transports the developer 8 by a rotating cylindrical magnetic roller 9.
  • the developer 8 held by the magnetic force on the magnetic roller 9 is regulated to an appropriate amount by the developer conveying amount regulating member 10 and then the developing gap portion where the latent image carrier 1 and the magnetic roller 9 come close to each other.
  • Transported to In this case, the surface of the magnetic material nozzle 9 is covered with a coating (not shown) made of at least one kind of conductive material, and in particular, a high resistance material such as a ferrite magnet.
  • the bias voltage is developed by the developing bias voltage applying means 10 because the coating layer functions as a developing electrode. Is applied to the developer 8, and the developer 8 adheres to the electrostatic latent image on the latent image carrier 1 according to the potential of the electrostatic latent image on the latent image carrier 1, thereby causing the developer 8 to adhere to the latent image carrier 1. Are visualized.
  • the developer 8 (on which the electrostatic latent image has been developed) on the latent image carrier 1 is transferred to the recording paper 15 by the transfer device 14 and is then fixed to the recording paper 15 by means such as pressure or heating. Thus, a desired image can be obtained.
  • one of the bias applying means 10 (the side not electrically connected to the support constituting the latent image carrier 1) is shown as electrically connected to the employee. Does not limit the present invention, as is apparent, one of the bias applying means 10 constitutes the magnetic roller 9, the magnet 12 or the yoke 13 electrically connected to the magnet 12, etc. It is only necessary that at least one conductive support or the coating layer be electrically connected.
  • One of the bias applying means 10 is a conductive support such as a yoke 13 electrically connected to the magnet 12 or the magnet 12 or the magnet 12 constituting the magnetic material aperture 9 or the coating layer.
  • the coating electrode according to the present invention recognizes a developing electrode effect such as an enhancement of an electric field due to a potential potential constituting an electrostatic latent image on the latent image carrier 1.
  • the magnet used as the magnetic roller 9 is preferably made of a high resistance material such as a filament.
  • the applying means 10 is connected to the coating layer, and It is desirable that the cover layer functions as a developing electrode.
  • a rare earth magnet or the like which is a conductive material provided with a coating layer according to the present invention or provided with a coating layer on extremely thin surface corrosion, was used so as to exert a sufficient effect as a surface corrosion prevention layer.
  • the magnetic roller 9 it is sufficient that the magnetic roller 9 is in contact with at least one of the magnets 12 or the conductive support such as the magnet 12 and the yoke 13 or the coating layer. A good developing electrode effect can be obtained.
  • a ferrite sintered magnet was used as the magnetic roller 9 and Ni was used as the coating layer (the coating was performed by Ni).
  • Example F1 the same configuration as in Example F1 was used except that A1 fine particles dispersed in an epoxy resin were used as the coating.
  • the procedure was performed except that the magnetic roller 9 was a summary, a cobalt-based injection-molded magnet, and A 1 was used as the coating (the plating was performed with A 1).
  • the configuration was the same as in Example F1.
  • Example F 4 An image was formed under the same conditions using an image forming apparatus using a developing device having the same configuration as in Example F3 except that the magnet was exposed without providing a coating layer on the surface of the magnetic roller 9. When images were formed continuously, the obtained images were blurred from the first printed sheet and could not be visually read.
  • Example F 4
  • the magnetic material roller 9 is used as a summary.
  • the configuration was the same as that of Example F 3 except that a palladium-based extruded magnet was used.
  • Example F4 the configuration was actually the same as that of Example F4, except that carbon black dispersed in a polyester resin was used as the coating.
  • An image corresponding to 100 A4 size plain paper was continuously formed using an image forming apparatus including the developing device having the above-described configuration, but the obtained image had high resolution similarly to the first print. High quality images were obtained.
  • neodymium iron-based sintered magnet was used as the magnetic roller 9 and A 1 was used as the coating layer.
  • the configuration was the same as that of Example F1 except that the plating was performed by A1.
  • an image equivalent to 500 000 sheets of A4 size ordinary paper is obtained at a temperature of 20 ° C. and a relative humidity of 60% under 3 ⁇ 45. Although it was formed continuously, no deterioration of the obtained image was observed, and a high-quality image with high resolution was obtained as in the case of the first printed sheet. Further, no oxidative corrosion of the surface of the magnetic roller 9 was observed.
  • Example F6 the same configuration as in Example F6 was used, except that a layer in which carbon black was dispersed in a polycarbonate resin was used as the coating layer.
  • A4 size plain paper was obtained under the same environment as in Example 6.
  • Example F6 was performed using an image forming apparatus having a configuration similar to that of Examples F6 and F7 except that the magnet was exposed without providing a coating layer on the surface of the magnetic roller 19. Under the same environment, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed. Deterioration such as blurring of the eyes and ground covering was observed, and oxidative corrosion was observed on the surface of the magnetic roller 9.
  • Example F1 the same as in Example F1 except that a brassiodium / iron-based magnet was used as the magnetic roller 9 and Ni was used as the coating layer (the plating was performed with Ni). Configuration.
  • Example F8 the same configuration as that of Example F8 was used except that a coating layer in which A1 fine particles were dispersed in a fluorine resin was used.
  • Example F6 Same as Example F6, except that the magnet was exposed without providing a coating layer on the surface of the magnetic material roller 9 except that the magnet was exposed.
  • an image equivalent to 50,000 sheets of A4 size plain paper was formed by using a gun, and the obtained image showed blurring such as brush eyes and deterioration of ground covering.
  • oxidation corrosion was observed on the surface of the magnetic roller 9.
  • the magnetic roller has a cylindrical magnetic roller that is magnetized to a plurality of magnetic poles, and the developer is placed on the magnetic roller by a magnetic field generated by the magnetic roller.
  • a cover made of at least one kind of conductive material is provided on the surface (developer transport surface) of the magnetic roller.
  • the conductive material functions as a developing electrode, thereby producing a high-quality image stably for a long period of time.
  • the amount of the developer transported is adjusted by adjusting only the magnetic pole pitch of the magnetic roller, or by a form such as the developer transport amount regulating member 10 shown in FIG.
  • the surface of the magnetic roller is in surface contact with the developing agent transport amount regulating member, and the end of the developer transport amount regulating member is not in contact with the magnetic roller. The provision of the developer conveyance amount regulating member can solve the above problem.
  • FIG. 4 is a schematic cross-sectional view of an image forming apparatus including a developing device according to the embodiment of the present invention.
  • the latent image carrier 1 rotating in the direction indicated by A in the figure is a photoconductive layer 3 coated on a conductive support 2, and the photosensitive layer 3 is charged by a charger 4.
  • the light emitted from the light source 5 is imaged on the photosensitive layer 3 by the imaging optical system 6 in accordance with the image to obtain a potential contrast.
  • a developing device 7 charges a developer 8 which is a component of the developer, and a cylindrical magnetic roller 9 which rotates the developer 8 in a direction indicated by B in the figure. To be transported.
  • the developer 8 held by the magnetic force on the roller 9 is regulated to an appropriate amount by the developer carrying amount regulating member 11, and then is moved to the developing gear portion where the latent image carrier 1 and the magnetic material roller 9 are close to each other.
  • the developer 8 is conveyed, and the developer 8 is charged with an electrostatic latent image on the latent image carrier 1 in accordance with the potential of the static latent image on the latent image carrier 1 and the bias voltage from the power supply 10 which is a developing bias voltage applying unit.
  • the electrostatic latent image on the latent image carrier 1 is visualized by adhering to the surface.
  • the developer transporting amount regulating member 11 is formed of an elastomer such as phosphor bronze, an elastic metal such as stainless steel, or polyurethane rubber, and the developing agent transporting amount regulating member 11 is used.
  • the free end, ie, the edge located downstream from the flow of the developed image 8 does not contact the magnetic roller 19, and the surface except the free end is in pressure contact and surface contact. According to such a configuration, when the magnetic roller 9 is rotated in the direction of A in the figure, the developer 8 follows the rotation of the magnetic roller 9 and the developer 8 moves along the magnetic roller 9 to regulate the amount of the developer transported.
  • the pressure applied to the magnetic roller 9 by the developer conveyance amount regulating member 11 is made uniform, and plastic deformation occurs even under extremely high pressure, in other words, under a wide range of pressure. Easy Alternatively, even when a developer having strong self-cohesiveness is used, it is possible to stably form a thinner developer with a uniform thickness.
  • the developer 8 (on which the electrostatic latent image has been developed) on the latent image carrier 1 is transferred to the recording paper 15 by the transfer device 14 and is then fixed to the recording paper 15 by means such as pressure or heating. Thus, a desired image can be obtained.
  • the rotation directions of the latent image carrier 1 and the magnetic roller 9 are shown as A and B in the figure, respectively. is not. Further, in the present invention, any known developer as a one-component magnetic brush developer and a two-component magnetic brush developer can be used.
  • the rotation direction of the magnetic roller and the rotation direction of the latent image carrier are set in opposite directions, and the peripheral speed of the magnetic roller is set to the peripheral speed of the latent image carrier.
  • the rotation direction of the magnetic roller is rotated in the opposite direction to the latent image carrier, and the circumferential speed of the magnetic roller is changed to the latent image carrier. From peripheral speed A faster speed can prevent the magnetic brush from over-supplying the developer at the trailing edge of the printing area, thereby eliminating unnecessary accumulation of developer on the trailing edge and improving image quality. it can.
  • the rotation direction (counterclockwise) of the magnetic roller 9 is opposite to the rotation direction (clockwise) of the latent image carrier 1, and both are transferred in the forward direction in the developing gap. In this way, it is possible to prevent the developer 8 from being supplied excessively to the rear end of the printing school, thereby reducing tailing, thereby improving the resolution.
  • the arrow indicates the rotation direction of each member.
  • a magnetic roller is composed of the yoke of IDB and the magnetic roller is rotated counterclockwise at 20 O rpm, while the latent image carrier having an outer diameter of 30 ⁇ 8 is opposed to the magnetic roller by 3 Orpro.
  • the image is formed by rotating it in the clockwise direction (clockwise), the trailing edge of the printing section is no longer trailing, and a high-contrast image without high-density unevenness can be formed stably.
  • the weight was reduced to less than half that of the conventional ffl magnet and metal sleeve.
  • a developing device as shown in Fig. 1 is composed of a summary rubber-cobalt compression-molded magnet with an outer diameter of 20 M and a thickness of 1.5 aa and magnetized into 40 poles, and a magnetic circuit inside it.
  • a magnetic roller is composed of an outer diameter of 17 M and a yoke with a thickness of 1 ma, and the magnetic roller is rotated counterclockwise at 200 ° to form a latent image carrier having an outer diameter of 3 O we.
  • the image was formed by rotating in the opposite direction (clockwise) to the magnetic roller at 30 rpi, the trailing edge of the printing section disappeared, and a high-density, high-contrast image with high density was stabilized.
  • the weight was reduced to less than half that of the conventional one using a ferrite magnet and a metal sleeve.
  • a magnetic roller is integrally formed with the 1 OM yoke having a wall thickness of 1 M, and the magnetic roller is rotated counterclockwise at 200 rpn.
  • the magnetic roller can be reduced to one-fourth or less the size of the conventional roller using a magnet and metal sleeve. I was able to.
  • the outer diameter 1 8 nnn thickness 1 constituting the magnetic circuit off line bets magnet divided magnetizing 6 0 poles at the outer diameter 2 0M thickness lm B and therein
  • a magnetic roller is composed with the yoke of ID » and the magnetic roller is rotated counterclockwise at 20 O rpm, while a latent image carrier having an outer diameter of 3 O inn is the same as the magnetic roller with 3 O rpin.
  • a conventional one-component magnetic developing device that uses a developer carrying member (non-magnetic metal sleeve) with an outer diameter of 20 BB, and uses a magnetic roller placed inside it with an outer diameter of 18 and a wall thickness of 5 to 8
  • the latent image carrier with an outer diameter of 30 ma is rotated clockwise at 3 Orpin, and the developer transport member is rotated at 20 O rpm.
  • the image was formed by rotating the magnetic roller in the same direction (clockwise) as the carrier and rotating the magnetic roller in the same direction (clockwise) as the latent image carrier at 1000 rpm.
  • a trail was generated and only low-contrast, low-resolution images could be formed.
  • a conventional one-component magnetic developing device that uses a developer carrying member (non-magnetic metal sleeve) with an outer diameter of 20 ma and uses a magnetic roller placed inside it with an outer diameter of 18 ⁇ 1 thick 5 It is composed of sintered magnets divided into 10 poles and divided into 8 poles, and the latent image carrier having an outer diameter of 30 M is rotated clockwise at 30 °, and the developer transport member is rotated by 20 °. Rotate the magnetic roller in the direction opposite to the latent image carrier (counterclockwise) at rpm, and rotate the magnetic roller in the same direction (clockwise) as the latent image carrier at 100 ° As a result, tailing occurred at the rear end of the printed portion, and only low-resolution images with low contrast could be formed. Also, the weight of the magnetic roller can be reduced.
  • the rotation direction of the magnetic material roller and the rotation direction of the latent image carrier are set to one direction, and the developing gap portion (the magnetic material roller and the latent image carrier) is set.
  • the image quality can be further improved by setting the gap between (the part closest to the surface) to be larger than the minimum height of the developer ears held on the magnetic roller. Can be.
  • the image blocking force of the magnetic roller is sufficiently increased, and the image is prevented from being applied to the background (ground portion).
  • the adhesion of the image agent can be reduced.
  • the developer is brought into intermittent contact or non-contact with the latent image carrier, thereby reducing unnecessary adhesion of the developer and reducing the image product K. It can be improved.
  • a developing magnet as shown in Fig. 1 is a magnet with an outer diameter of 20M and a thickness of 1M, magnetized into 60 poles, and an outer diameter of 18 ran which forms a magnetic circuit inside the magnet.
  • a magnetic roller was constructed with the yoke and the magnetic roller was rotated clockwise by 20 Orpin.
  • a latent image carrier having an outer diameter of 3 Omni is rotated at 30 rpni in the same direction (clockwise) as the magnetic roller, and the developing gear is brought into contact with the latent image carrier so that the developer does not contact the latent image carrier.
  • a developing device as shown in Fig. 1 is a compression molded magnet of the samarium cobalt system, which is magnetized into 40 poles with an outer diameter of 20 BB and a thickness of 1.5 BB, and an outer part constituting a magnetic circuit therein.
  • a magnetic roller composed of a yoke with a diameter of 17 M and a thickness of 1 ran, 6 i Rotate the magnetic roller clockwise at 50 rpi, and rotate the latent image carrier with an outer diameter of 30 M in the same direction (clockwise) as the magnetic roller with 3 O rpin to form an image.
  • the trailing edge of the printed portion was no longer trailing, and high-density, high-contrast images could be stably formed.
  • the weight was reduced to less than half that of the conventional one using a ferrite magnet and a metal sleeve.
  • a yoke with a wall thickness of 1 ran is used to form a magnetic roller, and the magnetic roller is rotated clockwise at 50 ° while the latent image carrier having an outer diameter of 20 is rotated by 20 °.
  • the weight of the magnetic roller can be reduced to less than one-fourth that of the conventional one using a magnet and a metal sleeve.
  • the conventional one-component magnetic developing device uses a developer transporting member (non-magnetic metal sleeve) with an outer diameter of 20 M, and a magnetic roller disposed inside it with an outer diameter of 18 mm and a wall thickness of 5 mm.
  • a developer transporting member non-magnetic metal sleeve
  • a magnetic roller disposed inside it with an outer diameter of 18 mm and a wall thickness of 5 mm.
  • 8 poles -51 1-Composed of split magnetized sintered magnets the latent image carrier with an outer diameter of 30 na is rotated clockwise at 30 rpra, and the developer transport member is rotated at 200 rpm.
  • the image was formed by rotating the magnetic roller in the same direction (clockwise) as the image carrier and rotating the magnetic roller in the same direction (clockwise) as the latent image carrier at 1000 rpm.
  • a tail was generated, and only a low-contrast, low-resolution image could be formed.
  • magnetic rollers cannot be made lighter
  • the conventional one-component magnetic developing device uses a developer transport member (non-magnetic metal sleeve) with an outer diameter of 2 O rnii and a magnetic roller installed inside the roller. It is composed of a sintered fine magnet divided into 8 poles at »n.
  • the latent image carrier having an outer diameter of 30 M is rotated clockwise at 30 rpm, and the developer conveying member is rotated at 200 rpm.
  • To rotate in the opposite direction (counter clockwise) to the latent image carrier and rotate the magnetic roller at 100 rpm in the same direction (clockwise) as the latent image carrier to form an image.
  • tailing occurred at the rear end of the printed portion, and only low-resolution, low-resolution images could be formed. Also, it is not possible to reduce the weight of the magnetic roller.
  • a magnetic field is generated by a developing / transporting member. Irregularities in the developer (magnetic brush irregularities) due to the change are formed, and when the magnet is rotated, the development nip length fluctuates with the rotation of the magnet. May occur.
  • a magnetic field detecting means for detecting a magnetic field of the magnetic roller, and a developing means for changing a developing bias voltage in synchronization with an alternation of a magnetic field detected by the magnetic field detecting means.
  • the developing bias is changed in synchronization with the alternation of the magnetic field in the developing nip portion, the developing force acting on the developing agent in the developing nip portion can be kept constant, and the fluctuation in the developing density can be reduced.
  • a current bias voltage synchronized with the alternation of the magnetic field can be applied between the power supply and the latent image carrier.
  • FIG. 5 is a schematic cross-sectional view of an image forming apparatus including a developing device according to the embodiment of the present invention.
  • the latent image carrier 1 is formed by coating an organic or inorganic photoconductive light-sensitive layer 3 on a conductive support 2. After the photosensitive layer 3 is charged using a charger 4 such as a corona charger, the photosensitive layer 3 emits light in accordance with an image. The light emitted from the source 5 is selectively irradiated on the photosensitive layer 3 through the imaging optical system 6 to obtain a potential contrast on the photosensitive layer 3 to form an electrostatic latent image.
  • a charger 4 such as a corona charger
  • a developing device 7 charges a developer 8 as an image forming body and transports it by a cylindrical magnetic roller 9 so that the latent image carrier 1 and the magnetic roller 9 are close to each other.
  • Developing the developer 8 in accordance with the potential potential of the electrostatic latent image on the latent image carrier 1 and the bias pressure by the developing bias voltage applying means 10.
  • the latent image is visualized by the developer 8.
  • the developer 8 that visualizes the electrostatic latent image is transferred to a recording paper 15 by a transfer unit 14 using corona discharge, electric field, pressure and adhesive force, and is then transferred to the developer by means such as pressurization or heating. 8 is fixed on the recording paper 15 to obtain a desired image on the recording paper 15 by the developer 8.
  • the magnetic roller 9 holds the supplied developing roller 8 by magnetic force, and conveys the developer 8 by regulating the conveyance amount regulating member 11 to an appropriate amount.
  • the magnetic roller 9 comprises a magnet 12 having a cylindrical shape and the outer circumference of which is magnetized to a plurality of poles, and a magnetic circuit comprising a magnetic yoke (not shown) provided inside the magnet 12.
  • a magnetic field is formed on a cylindrical, non-magnetic developer conveying member 13 disposed through a gap with a magnet 12 to convey a magnetic developer 8, as shown in FIG.
  • a magnetic field detecting means 16 is provided adjacent to the magnetic roller 9 and a magnetic field generated by the magnet 12 of the developing gear portion is provided.
  • the alternating voltage is applied to the developing bias applying means 10 by the S means 17 in accordance with the change in the developing inhibiting force due to the magnetic field of the developing gap, and the developing force (Coulomb force) ) And the difference between the development inhibiting force due to the magnetic field is kept constant, the fluctuation of the force acting on the developer 8 is reduced, and therefore the unevenness of the development density due to the rotation of the magnet 12 is reduced, and the image of print quality is reduced. Can be formed.
  • the magnetic field detecting means 16 may be provided as long as it is close to the magnetic roller 9, so that the developing force is converted into a magnetic field at the image gap position to keep the developing force constant.
  • the waveform of the alternating voltage can be applied irrespective of the type of sine wave, rectangular wave, sawtooth wave, and the like.
  • FIGS. 6A and 6B are diagrams showing an applied state of the alternating voltage in the embodiment of the present invention, in which the alternating voltage is applied at a half cycle of the magnetization reversal cycle.
  • the developing electric field is small at the time when the center of the magnetic pole with the high brush height passes through the developing gap, and the developing is performed at the time when the magnetic pole with the low magnetic brush height passes through the developing gap.
  • the magnetic field detecting means detects not only known elements such as a Hall element, a magnetoresistive element, and a coil, but also the rotational position of the magnet. It is clear that the alternating voltage can be similarly increased even if the magnetic field (magnet rotation position ⁇ ) is detected indirectly by using a known optical encoder or mechanical switch.
  • the magnetic flux density on the developer conveying member is 800 [G]
  • the developer is conveyed by a magnetic roller using magnets magnetized to eight poles, and the latent image is transferred to the developing device.
  • a magnetic field detecting means is arranged near the developing gap, and the developing bias voltage is applied to a DC component of 550 [V] and an AC of ⁇ 200 [V].
  • the center of the magnetic pole passes through the center of the developing gap at twice the frequency of the magnetic field change frequency, the alternating voltage is superimposed so that the absolute value of the developing bias 3 ⁇ 4 pressure is reduced, and image formation is performed by reversal development.
  • Example I 1 Using a magnetic roller as shown in Fig. 5, the developer is directly transported using a rare earth magnet magnetized to 32 poles with a magnetic density of 400 [G] on the magnet, and the magnetic field is detected.
  • An image was formed using the same configuration as in Example I1 except that the optical encoder at the end of the magnetic roller was used to indirectly detect the density of the solid image. A high print quality image with a small change in line width was formed; Comparative Example I 1
  • Example I1 An image was formed using the same configuration as in Example I1 except that no alternating voltage was applied.As a result, uneven development density corresponding to the change in the magnetic field occurred in the solid image, and the line width of the fine line changed. Only images with poor print quality and poor gradation were obtained.
  • the developing bias voltage is changed to a DC component of 1550 [V] with an alternating voltage of 10000 [V], and the frequency of the alternating voltage is about 10 times (several kiloHz) the change frequency of the magnetic field.
  • An image was formed with the same configuration as in Example I1 except that the voltage was applied in such a manner as to obtain a uniform image. Only poor quality images were obtained.
  • the developing device of the present invention can be widely used for image recording means using an electrophotographic process, and can be particularly widely applied as a developing device for a printing machine, a copying machine or a facsimile machine.

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Abstract

An apparatus for developing an electrostatic latent image formed on a latent image support in an electrophotographic image recording appartus. The apparatus includes a cylindrical magnetic roller (9) having a plurality of magnetic poles and made of rare earth metal magnets. A developer (8) is directly supplied onto the magnetic roller (9), held on the surface of the magnetic roller by the magnetic field generated by the magnetic roller, and transferred by the rotation of the magnetic roller. Thus, the construction of the apparatus can be simplified and image quality can be improved.

Description

明 钿 害 現 像 装 置 技 術 分 野  Lighting damage Image device technology
本発明は電子写真プロセスを用いた画像記録装置に関 し、 さらに詳しく は、 潜像担持体に形成された静電潜像 パターンを現像するための現像装置に関する。  The present invention relates to an image recording apparatus using an electrophotographic process, and more particularly, to a developing device for developing an electrostatic latent image pattern formed on a latent image carrier.
従 来 技 術  Conventional technology
従来の現像装置としては、 磁気ブラシ現像装置 （一成 分磁気ブラシ及び二成分磁気ブラシ） として公知のよう に、 回転自在なステンレスやアルミニウムや黄銅に代表 されるような非磁性かつ導電性の円筒状の現像剤搬送部 材 （現像スリーブとも称す） の内部に、 複数の磁極に着 磁された円筒状の磁性体ローラーを具備するものが知ら れている。 このようなスリーブを用いた現像装置におい ては、 磁性体ローラーにより発生する磁場にしたがって 現像剤搬送部材上に現像剤を保持するとともに磁性体口 一ラーもしく は現像剤搬送部材のうち少なく とも一方を 回転させて、 現像剤搬送部材上の現像剤を搬送するもの が主流である。  As a conventional developing device, as is known as a magnetic brush developing device (one-component magnetic brush and two-component magnetic brush), a rotatable non-magnetic and conductive cylinder represented by stainless steel, aluminum or brass is used. 2. Description of the Related Art There is a known type in which a cylindrical developer roller (also referred to as a developing sleeve) is provided with a cylindrical magnetic roller magnetized by a plurality of magnetic poles. In a developing device using such a sleeve, the developer is held on the developer conveying member in accordance with the magnetic field generated by the magnetic roller, and at least one of the magnetic material port and the developer conveying member is used. The mainstream is to rotate one side to transport the developer on the developer transport member.
しかし、 前述の従来技術では、 磁性体ローラーの外径 を研磨加工して外径精度を出し、 この磁性体ローラーと 現像剤搬送部材とを微小な空隙を隔てて精度良く配設す る必要があり、 このため工数の増大及びコス トアップを 生じており、 磁性体ローラーのみならず現像剤搬送部材 の外径加工も必要で一層現像装置を高価なものにしてい た。 また、 磁性体ローラーや現像剤搬送部材ゃそれぞれ を支持する部品ならびにそれに付随する構成部品が多く なり、 このため現像装置の小型軽量化に支障をきたして いた。 さらに、 磁性体ローラーを回転した場合に得られ る画像に特有の磁性体ローラーの磁極ピッチによる現像 濃度むらを低減するために、 磁性体ローラーの着磁極数 を増すと現像剤搬送部材上で十分な漏洩磁束が確保でき ず、 現像剤の搬送に支障をきたしていた。 However, in the above-described conventional technology, the outer diameter of the magnetic roller is polished to obtain the outer diameter accuracy, and the magnetic roller and the developer conveying member are accurately arranged with a small gap therebetween. Therefore, the number of man-hours and cost have been increased, and the outer diameter of not only the magnetic roller but also the developer conveying member has been required, thus making the developing device more expensive. In addition, the number of components that support the magnetic roller and the developer conveying member な ら び に and the components associated therewith are increased, which has hindered the reduction in size and weight of the developing device. Furthermore, if the number of magnetized poles of the magnetic roller is increased, the number of magnetized poles of the magnetic roller is sufficient to reduce unevenness in development density due to the magnetic pole pitch of the magnetic roller, which is unique to the image obtained when the magnetic roller is rotated. As a result, a large amount of magnetic flux could not be secured, which hindered the transport of the developer.
発 明 の 開 示  Disclosure of the invention
本発明はこのような問題点を解決するもので、 その目 的とするところは、 磁性体ローラーの表面で直接現像剤 を搬送する現像装置構造とすることにより、 製造から組 立に至るまでの工数が少なく低コス トの現像装置を提供 するところにある。 更に他の目的は、 小型軽量の現像装 置を提供することにある。 更に他の目的は、 磁性体ロー ラーにより生じる磁場を有効に活用し十分な現像剤の搬 送量を確保して高港度の現像濃度の得られる現像装置を 提供することにある。 更に他の目的は、 磁性体ローラー による現像濃度むらを低減し高い印字品質の得られる現 像装置を提供することにある。  The present invention solves such a problem. The purpose of the present invention is to provide a developing device structure that transports the developer directly on the surface of the magnetic roller, thereby making it possible to cover all processes from manufacturing to assembly. The aim is to provide a low-cost developing device with less man-hours. Still another object is to provide a small and lightweight developing device. It is still another object of the present invention to provide a developing device capable of effectively utilizing a magnetic field generated by a magnetic roller, securing a sufficient amount of developer to be conveyed, and obtaining a high-concentration developing density. It is still another object of the present invention to provide an imaging apparatus capable of reducing unevenness in development density by a magnetic roller and obtaining high printing quality.
すなわち、 本発明の現像装置、 電子写真プロセスを用 いた画像記録装置において潜像担持体に形成された静電 潜像パターンを現像するための現像装置であって、 複数 の磁極が着磁されてなる円筒状の磁性体ローラーを具備 し、 この磁性体ローラー上に現像剤を直接供耠して磁性 体ローラーにより発生する磁場によって前記現像剤を磁 性体ローラー表面に保持するとともに、 前記磁性体ロー ラーを回転させて前記担持された現像剤を搬送するよう にしたことを特徴とするものである。 That is, the developing device of the present invention uses the electrophotographic process. A developing device for developing an electrostatic latent image pattern formed on the latent image carrier in the image recording apparatus, comprising a cylindrical magnetic roller formed by magnetizing a plurality of magnetic poles. The developer is directly supplied onto the body roller to hold the developer on the surface of the magnetic roller by a magnetic field generated by the magnetic roller, and the magnetic roller is rotated to remove the carried developer. It is characterized by being transported.
上記の本発明によれば、 従来磁性体ローラーの外周側 に配設されていた現像剤搬送部材 （スリーブ） を省略し て簡略な構造の現像装置を構成することができる。 また、 磁性体ローラーで現像剤を直接搬送するため、 磁性体口 一ラー （磁石） の発生する磁界を最も有効に活用するこ とが出来る。 さらに、 磁気特性の高い希土類の磁石によ り磁性体ローラーを形成して、 小型軽量の磁性体ローラ 一を構成することができ、 射出成形や圧縮成形や押出成 形により磁石を成形して寸法精度にすぐれ、 しかも後加 ェが不要な磁性体ローラーを構成することができる。 特 に、 磁気回路を構成する钦磁性材料からなるヨークを磁 性体ローラーの内部に組み込んで機械的強度及び磁気特 性を向上させることが出来る。 その他の本発明の特徴は、 以下の記載によって明らかとなるであろう。  According to the present invention described above, a developing device having a simple structure can be configured by omitting the developer conveying member (sleeve) conventionally disposed on the outer peripheral side of the magnetic roller. Also, since the developer is directly transported by the magnetic roller, the magnetic field generated by the magnetic roller (magnet) can be used most effectively. Furthermore, a magnetic roller made of a rare-earth magnet with high magnetic properties can be used to form a compact and lightweight magnetic roller.The magnet is formed by injection molding, compression molding, or extrusion molding. A magnetic roller having excellent accuracy and requiring no post-processing can be configured. Particularly, the mechanical strength and magnetic properties can be improved by incorporating a yoke made of a magnetic material constituting a magnetic circuit into the inside of the magnetic roller. Other features of the present invention will become apparent from the following description.
図面の簡単な説明  BRIEF DESCRIPTION OF THE FIGURES
第 1図、 第 4図および第 5図は、 各々、 本発明の現像 装置の概要を説明する図であり、 FIG. 1, FIG. 4 and FIG. FIG. 2 is a diagram illustrating an outline of the device,
第 2図は、 現像装置が具備する磁性体ローラーの断面 概要図であり、  FIG. 2 is a schematic cross-sectional view of a magnetic roller provided in the developing device.
第 3図は、 磁性体ローラーの表面に現像剤の保持され ている様子を説明する断面概要図であり、  FIG. 3 is a schematic cross-sectional view illustrating a state in which the developer is held on the surface of the magnetic roller.
第 6 A図ならびに第 6 B図は、 各々、 交番電圧の印加 状態を示す図である。  FIG. 6A and FIG. 6B are diagrams each showing an applied state of an alternating voltage.
* 発明を実施するための最良の形態  * Best mode for carrying out the invention
第 1図は本発明の具体的態様における現像装置を含む ,画像形成装置の断面概観図である。 潜像担持体 1は、 導 電性の支持部 2の上に、 有機または無機の光導電性材料 からなる感光雇 3を形成したものである。 この感光雇 3 に対してコロナ帯電器等の帯電器 4を用いて帯電を行つ た後に、 画像に応じて光源 5から出た光を結像光学系 6 を適して感光層 3に選択的に光照射して感光層 3上に電 位コン トラス トを得て所望の静電 ίϊ像パターンを形成す る。 一方、 現像装置 7は像形成体である現像剤 8を帯電 させ、 かつ、 円筒状の磁性体ローラー 9で搬送して、 潜 像担持体 1 と磁性体ローラー 9とが近接する現像ギヤッ ブ部において潜像担持体 1の静電潜像の電位ポテンシャ ル及び現像バイアス電圧印加手段 1 0によるバイアス電 圧に応じて現像剤 8を現像するものである。 このように して潜像担持体 1の静電潜像を現像剤 8により顕像化す る ο 静電潜像を顕像化した現像剤 8は、 コロナ放電や電界 や圧力や粘着力を用いた転写器 1 4により記録紙 1 5に 転写し、 加圧や加熱等の手段により現像剤 8を記録紙 1 5に定着して、 記録紙 1 5上に現像剤 8による所望の 画像を得るものである。 FIG. 1 is a schematic cross-sectional view of an image forming apparatus including a developing device according to a specific embodiment of the present invention. The latent image carrier 1 is formed by forming a photosensitive member 3 made of an organic or inorganic photoconductive material on a conductive supporting portion 2. After the photosensitive member 3 is charged using a charger 4 such as a corona charger, light emitted from a light source 5 is selectively applied to the photosensitive layer 3 by an imaging optical system 6 according to an image. Irradiation is performed to obtain a potential contrast on the photosensitive layer 3 to form a desired electrostatic image pattern. On the other hand, a developing device 7 charges a developer 8 which is an image forming body, and conveys the developer by a cylindrical magnetic roller 9 so that the latent image carrier 1 and the magnetic roller 9 are close to each other. The developer 8 is developed according to the potential potential of the electrostatic latent image on the latent image carrier 1 and the bias voltage by the developing bias voltage applying means 10. Thus, the electrostatic latent image on the latent image carrier 1 is visualized by the developer 8 ο The developer 8 that visualizes the electrostatic latent image is transferred to a recording paper 15 by a transfer unit 14 using corona discharge, electric field, pressure, or adhesive force, and the developer 8 is pressed or heated. Is fixed on the recording paper 15 to obtain a desired image by the developer 8 on the recording paper 15.
第 1図の現像装置において、 磁性体ローラー 9は、 供 給された現像剤 8を磁気力により保持しながら、 搬送量 規制部材 1 1で適量に規制して現像剤 8を搬送するもの である。 この磁性体ローラー 9は、 円筒状で外周を複数 ,極に着磁された磁石 1 2と软磁性材料からなる円筒状の ヨーク 1 3とで磁気回路を構成することができる。 この 磁石 1 2の外周の漏洩磁束により磁性の現像剤 8を磁性 体ローラー 9上に直接保持した状態で磁性体ローラー 9 を回転させて現像剤 8を直接に搬送することができる。 これにより磁束を最も有効に使用することができる。 し たがって薄肉磁石でも従来以上の磁気拘束力が得られる t 尚、 第 1図において、 矢印はそれぞれの部材の回転方向 を示すが、 本発明はこれに限定されるものではない。 In the developing device shown in FIG. 1, the magnetic roller 9 conveys the developer 8 while holding the supplied developer 8 by a magnetic force while regulating the transport amount regulating member 11 to an appropriate amount. . The magnetic roller 9 can form a magnetic circuit with a magnet 12 having a plurality of cylindrical outer circumferences and poles magnetized and a cylindrical yoke 13 made of a diamagnetic material. By rotating the magnetic roller 9 while the magnetic developer 8 is directly held on the magnetic roller 9 by the magnetic flux leaking from the outer periphery of the magnet 12, the developer 8 can be directly conveyed. Thereby, the magnetic flux can be used most effectively. Therefore Incidentally t magnetic binding force than conventional in thin magnet can be obtained, in FIG. 1, arrows show the direction of rotation of the respective members, the present invention is not limited thereto.
上記のように、 本発明においては、 磁性体ローラーを 薄肉円筒状とし、 かつ、 その内部を実質的に中空構造に することによって、 磁性体ローラーの設置、 取り外しと いった扱いがきわめて容易になるだけでなく、 磁性体口 一ラーを回転させる際には磁性体の慣性モーメ ン 卜が小 さいため回転の立ち上がりが速く、 低速回転時、 高速回 転時ともに回転ムラがほとんどなく、 回転に必要な トル ク も小さくてすむというすぐれた効果を奏する。 すなわ ち、 磁性体ローラー 9の内部は中空であり惯性モーメ ン トが小さく、 磁性体ローラー 9を回転させる際には回転 の立ち上がりが速く、 低速回転時、 高速回転時を問わず 回転ムラがほとんどなく、 回転に必要とする トルクも小 さくてすみ、 過不足のない安定した現像剤供耠を行うこ とができ、 したがって現像濃度ムラを低減して高い印字 品質を得ることができる。 As described above, in the present invention, by setting the magnetic roller in a thin cylindrical shape and having a substantially hollow structure inside, the handling such as installation and removal of the magnetic roller becomes extremely easy. In addition, when rotating the magnetic material aperture, the inertia moment of the magnetic material is small, so the rotation rises quickly, and when rotating at low speed, rotating at high speed. It has an excellent effect that there is almost no rotation unevenness during rotation and the torque required for rotation is small. That is, the interior of the magnetic roller 9 is hollow and has a small amount of elasticity. When the magnetic roller 9 is rotated, the rotation rises quickly, and uneven rotation occurs at low speed and high speed. There is almost no need for the torque required for rotation, and the developer can be supplied stably without excess or shortage. Therefore, high print quality can be obtained by reducing unevenness in the development density.
第 2図は、 本発明の他の具体例における現像装置の磁 性体ローラーの概観図である。 円筒状で半径方向に複数 極に着磁された希土類磁石からなる磁石 1 2の外周表面 に現像剤を磁界分布に応じて保持かつ搬送するもので、 磁性体ローラー 9は鉄などを主成分とする钦磁性のョー ク 1 3を磁石 1 2の内周側に接着等の手段により配設し て磁気回路を構成するものである。'また、 本発明におい ては、 磁石 2 2を希土類磁石で構成することにより、 こ れを薄肉化することができるので、 磁石重量を従来の半 分以下にして、 しかも、 磁石 1 2の着磁極数を 1 0極以 上に多極着磁してヨーク 1 3の重量も軽量化することが 可能となる。  FIG. 2 is a schematic view of a magnetic roller of a developing device according to another embodiment of the present invention. The developer is held and transported according to the magnetic field distribution on the outer peripheral surface of a magnet 12 composed of a cylindrical rare earth magnet magnetized in a plurality of poles in the radial direction.The magnetic roller 9 is mainly composed of iron or the like. A magnetic circuit is constructed by arranging a magnetic yoke 13 on the inner peripheral side of the magnet 12 by bonding or the like. In addition, in the present invention, the magnet 22 can be made thin by forming the magnet 22 from a rare earth magnet. By magnetizing the number of magnetic poles to 10 or more, the weight of the yoke 13 can be reduced.
尚、 钦磁性材料からなるヨーク 1 3を、 磁石の成形時 予め成形型に設置し、 その外周において磁性粉や樹脂等 を含む磁石材料を射出成形することにより磁石 1 2とョ ーク 1 3とを一体成形して磁性体ローラー 9を形成する ことができる。 このような方法によれば、 プラスチック の射出成形で容易に一体成形がてき、 磁石の肉厚を The yoke 13 made of a magnetic material is placed in a molding die before molding the magnet, and a magnet material containing magnetic powder, resin, or the like is injection-molded on the outer periphery of the yoke 13 so that the magnet 12 and the magnet 13 are joined together. The magnetic material roller 9 can be formed by integrally molding the magnetic material roller 13 and the magnetic material roller 13. According to such a method, integral molding can be easily performed by plastic injection molding, and the thickness of the magnet can be reduced.
0 . 5〜2 M程度の薄肉餍にした場合においても十分な 機械的強度を得ることができる。 さらに、 磁性体ローラ 一 9の外径部の振れを 2 5 m以下に低滅することがで き、 これにより現像剤の搬送量の変動及び現像ギャ ップ の変動を低滅することができる。  Sufficient mechanical strength can be obtained even when the thickness is reduced to about 0.5 to 2 M. Further, the run-out of the outer diameter portion of the magnetic roller 19 can be reduced to 25 m or less, whereby the fluctuation of the amount of transported developer and the fluctuation of the developing gap can be reduced.
本発明に使用する現像剤としては、 一成分磁気ブラシ 現像剤及び二成分磁気ブラシ現像剤として公知である現 像剤がすべて適用可能である。 また、 本発明に使用する 磁性体ローラーの磁石材料としては、 フユライ ト磁石や アルニコ磁石やマンガンアルミ磁石や希土類磁石等の公 知の磁石材料を使用することが出来る。  As the developer used in the present invention, all developers known as a one-component magnetic brush developer and a two-component magnetic brush developer can be applied. Further, as the magnet material of the magnetic roller used in the present invention, known magnet materials such as a fluoride magnet, an alnico magnet, a manganese aluminum magnet, and a rare earth magnet can be used.
特に、 原子番号 5 8の C e力、ら 7 1の L uに至る 1 4 個の希土類元素、 中でも N dや P rや S mに代表される 希土類元素に、 F eや N i や C oに代表される 3 d遷移 金属を加えた希土類磁石を磁石 2 2として使用すること により、 薄肉であっても高い磁界を得ることができ、 し たがって小型軽量の磁性体ローラーを構成することがで きる。 また、 前記のような焼結による製造方法だけでな く、 圧縮成形や射出成形や押し出し成形の製造方法を用 いた成形磁石を用いることもでき、 この場合は、 小型軽 量だけでなく形状自由度が高く磁界分布の自由度も大き くできる。 また、 成形磁石の場合は、 前述したように、 磁気回路を構成するヨーク等を成形時に一体にして形成 することができ、 後加工無しでも外径の振れを 2 5 u rn 以下にできるなど寸法精度の向上を図ることができる。 また、 接着等の繁雑な手段を用いないため、 磁気回路の 磁気抵抗のばらつきが小さく、 磁石表面の磁束密度を均 一にして磁束のばらつきによる現像剤 ¾送量の変動や現 像量の 動を低減することが可能となる。 さらに、 磁石 を薄肉化できるため、 外径 2 O BB程度の磁石であっても、 ,内外に着磁ヨークを配置して 1 0極以上の多極着磁を容 易に行うことができる。 したがって磁石の肉厚程度の着 磁ピッチで多極着磁して、 これにより現像剤擻送量の変 動及び現像量の変勐を低減することができる。 In particular, 14 rare earth elements, such as C e force with atomic number 58 and Lu of 71, among them, rare earth elements represented by Nd, Pr and Sm, Fe, Ni and C By using a rare-earth magnet to which a 3d transition metal, typified by o, is added as the magnet 22, a high magnetic field can be obtained even with a thin wall, and therefore a compact and lightweight magnetic roller can be constructed. I can do it. In addition to the manufacturing method using sintering as described above, a molded magnet using a manufacturing method such as compression molding, injection molding, or extrusion molding can be used. High degree of freedom of magnetic field distribution I can do it. In the case of a molded magnet, as described above, the yoke, etc., constituting the magnetic circuit can be integrally formed at the time of molding, and the deflection of the outer diameter can be reduced to 25 urn or less without post-processing. Accuracy can be improved. In addition, since complicated means such as bonding are not used, the variation in the magnetic resistance of the magnetic circuit is small, and the magnetic flux density on the magnet surface is equalized. Can be reduced. Further, since the thickness of the magnet can be reduced, even with a magnet having an outer diameter of about 2 OBB, a magnetized yoke can be arranged inside and outside to easily perform multipole magnetization of 10 or more poles. Therefore, multi-pole magnetization is performed at a magnetization pitch about the same as the thickness of the magnet, whereby fluctuations in the amount of developer transported and fluctuations in the amount of development can be reduced.
なお、 前述した希土類磁石の成形方法、 材料の詳細に ついては、 たとえば特開昭 6 0 — 1 9 4 5 0 3号および 特開昭 6 3 - 2 8 9 8 0 7号に開彔されている。  The molding method and material of the rare-earth magnet described above are disclosed in, for example, Japanese Patent Application Laid-Open Nos. Sho 60-194503 and 63-289708. .
以下、 更に詳細な実施例を示す。  Hereinafter, more detailed examples will be described.
実施例 A 1  Example A 1
第 1図に示されるような現像装置で、 外径 2 O M肉厚 4 OTのフユライ ト磁石とその内部に磁気回路を構成する 外径 1 2 na肉厚 2 naのヨークとで磁性体ローラーを構成 し、 磁石を 1 6極に分割着磁したところ、 磁石表面で 1 0 0 0ガウス以上の磁束密度が得られ十分な現像剤の 穂だちと搬送量が得られた。 また、 磁性体ローラ一は従 来の現像剤搬送部材である金属スリーブ分軽量化するこ とができた。 さらに、 この現像装置を用いて画像形成を 行ったところ、 磁性体ローラーを潜像担持体の線速度の 4倍以上の線速度で動かすと現像濃度むらは、 目視では 殆ど識別できなく なり、 高濃度でコン トラス トの高い画 像を安定して形成することが出来た。 In a developing device as shown in Fig. 1, a magnetic roller is composed of a 2 OM outer diameter, 4 OT thickness, 4 OT, and a yoke with an outer diameter of 1 2 na, thickness of 2 na, which constitutes a magnetic circuit inside. When the magnet was divided and magnetized into 16 poles, a magnetic flux density of 1000 gauss or more was obtained on the magnet surface, and a sufficient amount of developer and a sufficient transport amount were obtained. The magnetic roller is The weight can be reduced by the metal sleeve, which is a conventional developer conveying member. Further, when an image was formed using this developing device, when the magnetic roller was moved at a linear speed of four times or more of the linear speed of the latent image carrier, unevenness in the developing density became almost indistinguishable by visual observation. An image with a high contrast at a high density could be formed stably.
実施例 A 2  Example A 2
第 1図に示されるような現像装置で、 外径 2 0 Ba肉厚 1 . 5 milのサマリウムコバルト系の圧縮成形磁石とその 内部に磁気回路を構成する外径 1 7 ma肉厚 I OTのヨーク とで磁性体ローラーを構成し、 磁石を 4 0極に分割着磁 したところ、 磁石表面で 1 0 0 0ガウス以上の磁束密度 が得られ十分な現像剤の穂だちと搬送量が得られた。 ま た、 磁性体ローラーは従来のフヱライ ト磁石と金厲スリ ーブを用いたものに比べ半分以下に軽量化することがで きた。 さ らに、 この現像装置を用いて画像形成を行った ところ、 磁性体ローラーを潜像担持体の線速度の 2倍以 上の線速度で動かすと現像港度むらは、 目視では殆ど識 別できなく なり、 高濃度でコン トラス トの高い画像を安 定して形成することが出来た。  In a developing device as shown in Fig. 1, a samarium-cobalt-based compression-molded magnet with an outer diameter of 20 Ba and a thickness of 1.5 mil and an outer diameter of 17 ma with an outer diameter of 17 ma that constitutes a magnetic circuit inside A magnetic roller is composed of the yoke and the magnet is divided and magnetized into 40 poles.As a result, a magnetic flux density of 100 gauss or more is obtained on the magnet surface, and a sufficient amount of developer spikes and transport amount can be obtained. Was. Also, the weight of the magnetic roller has been reduced to less than half that of the conventional roller using a magnet and a metal sleeve. Furthermore, when an image was formed using this developing device, when the magnetic roller was moved at a linear speed of twice or more the linear speed of the latent image carrier, unevenness in the developing port was almost visually discerned. This made it impossible to form images with high density and high contrast stably.
実施例 A 3  Example A 3
第 1図に示されるような現像装置で、 外径 1 2 M肉厚 1 maのサマリ ウムコバルト系の射出成形磁石とその内部 に磁気回路を構成する外径 1 0 M肉厚 1 maのヨークとで 磁性体ローラーを一体に形成し、 磁石を 4 0極に分割着 磁したところ、 磁石表面で 1 ◦ 0 0ガウス以上の磁束密 度が得られ十分な現像剤の穂だちと搬送量が得られた。 また、 磁性体ローラーは従来のフユライ ト磁石と金属ス リーブを用いたものに比べ 4分の 1以下に軽量化するこ とができた。 さらに、 この現像装置を用いて画像形成を 行ったところ、 磁性体ローラーを潜像担持体の線速度の 2倍以上の線速度で動かすと現像濃度むらは、 目視では 殆ど識別できなく なり、 高濃度でコン トラス トの高い画 ,像を安定して形成することが出来た。 Fig. 1 shows a developing device as shown in Fig. 1 with an injection-molded magnet made of samarium-cobalt with an outer diameter of 12M and a thickness of 1ma and a yoke with an outer diameter of 10M and a wall thickness of 1ma that forms a magnetic circuit inside. And in When the magnetic roller is formed integrally and the magnet is divided and magnetized into 40 poles, a magnetic flux density of 100 gauss or more is obtained on the magnet surface, and a sufficient amount of developer pan and transport amount are obtained. Was. Also, the weight of the magnetic roller was reduced to less than one-fourth that of the conventional roller using a magnet and a metal sleeve. Further, when an image was formed using this developing device, when the magnetic roller was moved at a linear velocity of twice or more the linear velocity of the latent image carrier, the development density unevenness became almost indistinguishable by visual observation. An image with a high contrast at a high density and an image could be formed stably.
実施例 A 4  Example A 4
第 1図に示されるような現像装置で、 外径 2 0 M肉厚 I nnのブラセォジゥム系の押し出し成形磁石とその内部 に磁気回路を構成する外径 1 8 ma肉厚 I BBのヨークとで 磁性体ローラーを構成し、 磁石を 6 0極に分割着磁した ところ、 磁石表面で 1 0 0 0ガウス以上の磁束密度が得 られ十分薄層化された現像剤の穂だちと搬送量が得'られ た。 また、 磁性体ローラーは従来のフユライ ト磁石と金 属スリーブを用いたものに比べ半分以下に軽量化するこ とができた。 さらに、 この現像装置を用いて画像形成を 行ったところ、 磁性体ローラーを潜像担持体の線速度よ り大きい線速度で動かすと現像濃度むらは、 目視では殆 ど識別できなく なり、 高濃度でコン トラス トの高い画像 を安定して形成することが出来た。 実施例 A 5 A developing device as shown in Fig. 1 is composed of a brassiodium-based extruded magnet with an outer diameter of 20 M and a thickness of Inn and a yoke with an outer diameter of 18 ma and an IBB with a thickness of BB constituting a magnetic circuit inside. When a magnetic roller is configured and the magnet is divided and magnetized into 60 poles, a magnetic flux density of 100 gauss or more can be obtained on the magnet surface, and a sufficiently thin layer of developer can be obtained with the conveyed amount of developer. ' In addition, the weight of the magnetic roller was reduced to less than half that of the conventional roller using a magnet and a metal sleeve. Further, when an image was formed using this developing device, when the magnetic roller was moved at a linear velocity higher than the linear velocity of the latent image carrier, unevenness in development density became almost indistinguishable by visual observation, and high density As a result, a high-contrast image could be formed stably. Example A 5
第 1図に示されるような現像装置で、 外径 2 0 M肉厚 Developing device as shown in Fig. 1, outer diameter 20 M
1 BBの樹脂バイ ン ドしたフユライ ト磁石とその内部に磁 気回路を構成する外径 1 8 M肉厚 I BHのヨークとで磁性 体ローラーを構成し、 磁石を 6 0極に分割着磁したとこ ろ、 磁石表面で 2 0 0ガウス以上の磁束密度が得られ薄 層の現像剤の穂だちと搬送量が得られた。 また、 磁性体 ローラーは従来のフェライ ト磁石と金属スリーブを用い たものに比べ半分以下に軽量化することができた。 さら に、 この現像装置を用いて画像形成を行ったところ、 磁 性体ローラーを潜像担持体の線速度より大きい線速度で 動かすと現像濃度むらは、 目視では殆ど識別できなく な り、 高饞度でコン トラス トの高い画像を安定して形成す ることが出来た。 A magnetic roller is composed of a 1 BB resin-bound fused magnet and an outer diameter of 18 M thick I BH yoke that constitutes a magnetic circuit inside, and the magnet is divided into 60 poles and magnetized. At this time, a magnetic flux density of 200 gauss or more was obtained on the magnet surface, and a thin layer of the developer and the transport amount were obtained. Also, the weight of the magnetic roller was reduced to less than half that of the conventional one using a ferrite magnet and a metal sleeve. Furthermore, when an image was formed using this developing device, when the magnetic roller was moved at a linear velocity higher than the linear velocity of the latent image carrier, unevenness in the development density became almost indistinguishable by visual observation. High-contrast images could be stably formed at a high temperature.
比較例 A 1  Comparative Example A 1
従来の一成分磁性現像装置で、 ^径 2 0 Mの現像剤搬 送部材 （非磁性の金属スリーブ） を用い、 その内部に配 設される磁性体ローラーを外径 1 8 11«肉厚 2 11»8に切削加 ェした焼結のフユライ ト磁石で構成したところ、 磁性体 ローラーを 8極以下に分割着磁しても現像剤搬送部材表 面では 5 0 0ガウス以下の磁束密度しか得られず十分な 現像剤の穂だちと搬送量は得られなかった。 また、 この 現像装置を用いて画像形成を行ったところ、 現像濃度の 不足したコン トラス トの低い画像しか形成することが出 来な力、つた。 The conventional one-component magnetic developing device uses a developer transporting member (non-magnetic metal sleeve) with a diameter of 20 M, and a magnetic roller disposed inside the roller. When composed of sintered ferrite magnets that were machined 11 118, even if the magnetic roller was divided and magnetized to 8 poles or less, only a magnetic flux density of 500 Gauss or less was obtained on the surface of the developer transfer member. As a result, no sufficient amount of developer and transport amount could be obtained. Also, when an image was formed using this developing apparatus, it was found that only a low-contrast image with insufficient developing density was formed. The coming power, Tsuta.
比較例 A 2  Comparative Example A 2
従来の一成分磁性現像装置で、 外径 2 0 iwの現像剤擻 送部材を用い、 その内部に配設される磁性体ローラーを 外径 1 8 Ba肉厚 5 Μに切削加工した焼結のフユライ ト磁 石で構成したところ、 磁性体ローラーを 8極以下に分割 着磁すれば現像剤搬送部材表面では 5 0 0ガウス以上の 磁束密 が得られ十分な現像剤の穂だちと搬送量が得ら れた。 しかし、 磁性体ローラーの重量は、 長さ 2 2 Ο ΐΜ ,で 0 . 4 kg以上となり軽量化することはできなかった。  Using a conventional one-component magnetic developing device, a developer roller with an outer diameter of 20 iw was used, and a magnetic roller provided inside was cut to an outer diameter of 18 Ba and a wall thickness of 5 mm. When the magnet is composed of fluite magnet, the magnetic roller is divided into 8 poles or less, and if it is magnetized, a magnetic flux density of 500 gauss or more can be obtained on the surface of the developer transfer member, and sufficient developer spikes and transfer amount can be obtained. I got it. However, the weight of the magnetic roller was not less than 0.4 kg with a length of 22 Ο, which could not be reduced.
以上実施例を述べたが、 本発明は以上の実施例のみな らず、 広く電子写真等の現像装置に応用することができ、 特にプリ ンターや複写機ゃファクシミ リやディ スプレー に応用すれば有効である。  Although the embodiments have been described above, the present invention is not limited to the above embodiments, and can be widely applied to developing devices such as electrophotography, especially if applied to printers and copiers, such as facsimile machines and displays. It is valid.
以上述べたように本発明によれば、 複数の磁極に着磁 された円筒状の磁性体ローラー上で直接現像剤を保持搬 送することにより、 製造から組立に至るまでの工数が少 なく低コス トの現像装置を提供することができる。 また、 構造が簡略化されるため、 小型軽量の現像装置を提供す ることができる。 さらに、 磁性体口一ラー表面の漏洩磁 束により現像剤を搬送するため、 磁性体ローラーにより 生じる磁場を有効に活用し十分な現像剤の搬送量を確保 して高漉度の現像濃度の得られる現像装置を提供するこ とができ、 しかも、 磁石を多極に着磁しても現像剤の保 持搬送に十分な磁気特性が得られ、 磁性体ローラーによ る現像濃度むらを低減し高い印字品質の得られる現像装 置を提供することができる。 As described above, according to the present invention, by directly holding and transporting the developer on a cylindrical magnetic roller magnetized on a plurality of magnetic poles, the man-hour from manufacturing to assembly is reduced. A cost developing device can be provided. Further, since the structure is simplified, a small and lightweight developing device can be provided. In addition, since the developer is transported by the magnetic flux leaking from the surface of the magnetic material, the magnetic field generated by the magnetic roller is effectively used to secure a sufficient amount of developer transport to obtain a high-density development density. Developing device that can be provided, and the developer can be retained even if the magnet is magnetized to multiple poles. It is possible to provide a developing device that has sufficient magnetic properties for carrying and transporting, reduces development density unevenness due to the magnetic roller, and obtains high printing quality.
また、 希土類磁石を磁性体ローラーの磁石として用い ることにより、 磁石の肉厚を薄く しても現像剤を保持搬 送するのに十分な磁界の得られる現像装置を提供するこ とができ、 これにより現像剤の磁性粉量を低減させるこ とができる。 さらに定着温度を下げてもすぐれた定着特 性を得ることができ、 表面光沢にもすぐれた画像の形成 ，が可能となる。  Further, by using a rare earth magnet as the magnet of the magnetic roller, it is possible to provide a developing device capable of obtaining a magnetic field sufficient to hold and transport the developer even when the thickness of the magnet is reduced, As a result, the amount of magnetic powder in the developer can be reduced. Furthermore, even if the fixing temperature is lowered, excellent fixing characteristics can be obtained, and an image with excellent surface gloss can be formed.
さらに、 成形磁石を磁性体ローラーの磁石として用い ることにより、 加工及び組立工数が少なく、 寸法精度が 良く、 磁気抵抗の少ない効率のよい磁気回路を構成する ことが出来る。  Furthermore, by using the molded magnet as the magnet of the magnetic roller, an efficient magnetic circuit with less processing and assembling man-hours, good dimensional accuracy, and low magnetic resistance can be formed.
さらに、 磁石の内部に钦磁性のヨークを含む磁性体口 一ラー構造とすることにより、 効率のよい磁気回路を構 成し、 磁性体ローラー表面で現像剤を保持搬送するのに 十分な磁束を得ることが出来る。  In addition, the magnet has a magnetic aperture with a magnetic yoke inside the magnet to form an efficient magnetic circuit, and a magnetic flux sufficient to hold and transport the developer on the surface of the magnetic roller. Can be obtained.
さらに、 圧縮成形磁石または射出形成磁石または押出 成形磁石を磁性体ローラーの磁石として用いることによ り、 加工及び組立工数が少なく、 寸法精度が良く、 薄肉 でも成形性に優れた磁性体ローラーを得ることができ、 磁性体ローラー表面で現像剤を保持搬送するのに十分な 磁束を得ることが出来る。 _ さらに、 磁性体ローラーの磁石を 1 0極以上に分割着 磁することにより、 磁性体口一ラーによる現像濃度むら を低減し高い印字品質の得られる現像装置を提供するこ とができる。 Furthermore, by using a compression molded magnet, an injection molded magnet, or an extruded magnet as a magnet for the magnetic roller, a magnetic roller having a small number of processing and assembling steps, good dimensional accuracy, and excellent moldability even with a thin wall can be obtained. Thus, a magnetic flux sufficient to hold and transport the developer on the surface of the magnetic roller can be obtained. _ Furthermore, by dividing and magnetizing the magnet of the magnetic roller into 10 or more poles, it is possible to provide a developing device capable of reducing unevenness in development density due to the magnetic material aperture and obtaining high printing quality.
以上のように本発明によれば、 小型軽量で安価で高画 質で画像を形成できる現像装 Sを提供することができる という優れた効果を奏する。  As described above, according to the present invention, there is an excellent effect that it is possible to provide the developing device S which is small, lightweight, inexpensive and can form an image with high image quality.
凹凸の形成  Formation of irregularities
次に、 磁性体ローラーの表面に凹凸を形成した態様に ，ついて説明する。  Next, an embodiment in which irregularities are formed on the surface of the magnetic roller will be described.
第 3図に示すように、 本発明のこの態様においては、 磁性体ローラー 9の磁石 1 2の外周部表面に凹凸が形成 されている。 この場合の凹凸は、 本図に示すように、 N および Sの各磁極の中心部分が凹部 （谷部） となり、  As shown in FIG. 3, in this embodiment of the present invention, irregularities are formed on the outer peripheral surface of the magnet 12 of the magnetic roller 9. In this case, as shown in this figure, the central part of each of the N and S magnetic poles becomes a concave part (valley part).
N S極の中間部分 （境界部分） が凸部となるように形成 することが好ま しい。 このような凹凸形状にすることに よって、 現像剤 8によって形成される磁気ブラシの外径 を磁極の位置によらず均一なものとすることができる。 この場合の凹凸形状の山の高さは、 形成される現像剤の 層厚の約半分程度の高さがあれば良好な均一化効果を得 ることができる。  It is preferable to form the intermediate portion (boundary portion) of the NS pole so as to be convex. With such an uneven shape, the outer diameter of the magnetic brush formed by the developer 8 can be made uniform regardless of the position of the magnetic pole. In this case, if the height of the peaks of the uneven shape is about half the thickness of the developer to be formed, a good uniformizing effect can be obtained.
磁性体ローラーの軸方向と円周方向に着目すると、 上 記の凹凸形状は以下のような関係にあることが好ましい, 磁性体ローラーが円周方向のみに複数の磁極に着磁さ れる場合は、 円周方向に磁極数と同数の凹凸を形成し、 磁性体ローラーが軸方向のみに複数の磁極に着磁される 場合は、 軸方向に磁極数と概ね同数の凹凸を形成し、 磁 性体ローラーが円周方向及び軸方向の双方向に複数の磁 極に着磁される場合は、 磁極の位置に応じて磁極数と概 ね同数の凹凸を形成することが望ま しい。 また、 凹凸形 状は着磁波数にもよるが、 円弧状もしく は正弦波状に凹 凸をつけると、 磁気ブラシの外径を均一にすることがで きる。 Focusing on the axial direction and the circumferential direction of the magnetic roller, it is preferable that the above-mentioned uneven shape has the following relationship.The magnetic roller is magnetized to a plurality of magnetic poles only in the circumferential direction. When the magnetic roller is magnetized to multiple magnetic poles only in the axial direction, the same number of irregularities as the number of magnetic poles are formed in the axial direction. However, when the magnetic roller is magnetized to a plurality of magnetic poles in both the circumferential direction and the axial direction, it is desirable to form as many irregularities as the number of magnetic poles in accordance with the positions of the magnetic poles. In addition, although the uneven shape depends on the number of magnetized waves, the outer diameter of the magnetic brush can be made uniform by forming a concave or convex shape in an arc shape or a sine wave shape.
このように凹凸を磁性体ローラーの表面層に形成する ことによつて現像剤の先端部の回転半径が磁極位置によ らず一定になるようにして、 接触現像の場合は現像ニッ プ幅を一定に保ち現像時閬及び磁気かきとり力を一定に して安定な画像港度を得ることができ、 非接触現像の場 合には現像電界を一定に保ち安定な画像'港度を得ること ができる。 また、 前述した圧縮成 ¾や射出成形や押し出 し成形等を用いることにより、 磁性体ローラーの表面に 所定の凹凸形状を容易に形成することができる。  By forming irregularities on the surface layer of the magnetic roller in this way, the radius of rotation of the tip of the developer is kept constant regardless of the magnetic pole position, and in the case of contact development, the width of the development nip is reduced. It is possible to obtain a stable image portability by keeping the temperature constant during development and the magnetic scraping force constant.In the case of non-contact development, it is possible to maintain a stable development field and obtain a stable image portability. it can. Also, by using the above-described compression molding, injection molding, extrusion molding, or the like, a predetermined uneven shape can be easily formed on the surface of the magnetic roller.
以下磁性体ローラー表面に凹凸を形成した場合の実施 例を示す。  An example in which irregularities are formed on the surface of a magnetic roller will be described below.
実施例 B 1  Example B 1
第 1図に示されるような現像装置で、 外径 2 0 ai«、 凸 部の肉厚 1 Bn、 凹部の肉厚 0 . 8 5 M、 凹部と凸部の数 が各々 6 0の樹脂バイ ン ドしたフェライ ト磁石とその内 6 一 部に磁気回路を構成する外径 1 8 肉厚 1 maのヨークと で磁性体ローラーを構成し、 磁石を 6 0極に分割着磁し たところ、 磁石表面で 2 0 0ガウス以上の磁束密度が得 られ薄層で現像剤の穂の外径が均一な磁性体ローラーが 得られた。 また、 磁性体ローラーは従来のフユライ ト磁 石と金属スリーブを用いたものに比べ半分以下に軽量化 することができた。 さらに、 この現像装置を用いて画像 形成を つたところ、 現像濃度むらは目視では殆ど識別 できなく なり、 高濃度でコン トラス 卜の高い画像を安定 , して形成することが出来た。 In the developing device as shown in FIG. 1, a resin vial having an outer diameter of 20 ai «, a thickness of a convex portion of 1 Bn, a thickness of a concave portion of 0.85 M, and a number of concave portions and convex portions of 60 each is used. Ferrite magnets and the 6 A magnetic roller is composed of an outer diameter of 18 and a yoke with a wall thickness of 1 ma that partially constitute a magnetic circuit.When the magnet is divided into 60 poles and magnetized, the magnet surface has more than 200 gauss. A magnetic roller having a high magnetic flux density and a thin layer of developer having a uniform outer diameter of the ear was obtained. In addition, the weight of the magnetic roller was reduced to less than half that of a conventional roller using a fumed magnet and a metal sleeve. Further, when an image was formed using this developing apparatus, unevenness in the developing density was hardly visually discerned, and a high-density, high-contrast image could be formed stably.
実施例 B 2  Example B 2
第 1図に示されるような現像装置で、 外径 2 0 aa、 凸 部肉厚 1 . 5 na、 凹部肉厚 1 . 3 5 M、 凹凸数が各々 4 0のサマリウムコバルト系の圧縮成形磁石とその内部 に磁気回路を構成する外径 1 7 M肉厚 I OTのヨークとで 磁性体ローラーを構成し、 磁石を 4 0極に分割着磁した ところ、 磁石表面で 1 0 0 0ガウス以上の磁束密度が得 られ薄層で現像剤の穂の外径が均一な磁性体ローラーが 得られた。 また、 磁性体ローラーは従来のフヱライ ト磁 石と金属スリーブを用いたものに比べより半分以下に軽 量化することができた。 さらに、 この現像装置を用いて 画像形成を行ったところ、 現像濃度むらは目視では殆ど 識別できなぐなり、 高濃度でコ ン トラス トの高い画像を 安定して形成することが出来た。 実施例 B 3 A samarium-cobalt-based compression-molded magnet with an outer diameter of 20 aa, a convex part thickness of 1.5 na, a concave part thickness of 1.35 M, and a number of irregularities of 40 each, as shown in Fig. 1. When a magnetic roller is composed of an outer diameter of 17 M and an IOT yoke that forms a magnetic circuit inside the magnet, the magnet is divided into 40 poles and magnetized. As a result, a magnetic roller having a thin layer and a uniform outer diameter of the developer ear was obtained. In addition, the weight of the magnetic roller was reduced to less than half that of the conventional roller using a magnet and a metal sleeve. Further, when an image was formed using this developing apparatus, unevenness in the developing density was almost indistinguishable by visual observation, and an image with high density and high contrast was stably formed. Example B 3
第 1図に示されるような現像装置で、 外径 1 2 ΒΒ、 肉 厚 1 IDB、 凹部肉厚 0 . 9 IM、 凹凸数が各々 4 0のサマリ ゥムコバルト系の射出成形磁石とその内部に磁気回路を 構成する外径 1 0 M、 肉厚 1 awのヨークとで磁性体ロー ラーを一体に形成し、 磁石を 4 0極に分割着磁したとこ ろ、 磁石表面で 1 0 0 0ガウス以上の磁束密度が得られ 薄屈で ί!像剤の穂の外径が一定の磁性体ローラーが得ら れた。 また、 磁性体ローラーは従来のフヱライ ト磁石と ,金厲スリーブを用いたものに比べ 4分の 1以下に軽量化 することができた。 さらに、 この現像装置を用いて画像 形成を行ったところ、 現像濃度むらは目視では殆ど識別 できなく なり、 高濃度でコン トラス 卜の高い画像を安定 して形成することが出来た。  A developing device as shown in Fig. 1 has an outer diameter of 12 mm, a thickness of 1 IDB, a concave wall thickness of 0.9 IM, and a number of irregularities of 40. A magnetic roller is integrally formed with a yoke with an outer diameter of 10 M and a wall thickness of 1 aW that constitutes the circuit.When the magnet is divided into 40 poles and magnetized, it is more than 1000 Gauss on the magnet surface. A magnetic roller with a constant outer diameter of the spike of the imaging agent was obtained. Also, the weight of the magnetic roller was reduced to one-fourth or less than that of a conventional magnet using a magnet and a metal sleeve. Further, when an image was formed using this developing apparatus, unevenness in the developing density was hardly visually discerned, and an image having a high density and a high contrast could be stably formed.
比較例 Β 1  Comparative Example Β 1
従来の一成分磁性現像装置で、 外径 2 O IDIIの現像剤搬 送部材 （非磁性の金属スリーブ） を用い、 その内部に配 設される磁性体ローラーを外径 1 8 M肉厚 2 BBに切削加 ェした焼結のフヱライ ト磁石で構成したところ、 磁性体 ローラーを 8極以下に分割着磁しても現像剤搬送部材表 面では 5 0 0ガウス以下の磁束密度しか得られず十分な 現像剤の穂だちと搬送量が得られなかった。 また、 この 現像装置を用いて画像形成を行ったところ、 現像濃度の 不足したコン トラス トの低い画像しか形成することが出 来な力、つた。 A conventional one-component magnetic developing device that uses a developer transport member (non-magnetic metal sleeve) with an outer diameter of 2 O IDII, and uses a magnetic roller placed inside the outer diameter of 18 M thick 2 B When composed of sintered bright magnets machined to B , even if the magnetic roller is divided and magnetized to 8 poles or less, only a magnetic flux density of 500 Gauss or less can be obtained on the surface of the developer conveying member. No sufficient amount of developer pan and transport amount were obtained. Also, when an image was formed using this developing apparatus, it was found that only a low-contrast image with insufficient developing density was formed. The coming power, Tsuta.
比較例 B 2  Comparative Example B 2
従来の一成分磁性現像装置で、 外径 20OTの現像剤搬 送部材を用い、 その内部に配設される磁性体ローラーを 外径 1 8OT肉厚 5OTに切削加工した焼結のフユライ ト磁 石で構成したところ、 磁性体ローラーを 8極以下に分割 着磁すれば現像剤搬送部材表面では 5 0 0ガウス以上の 磁束密 が得られ十分な現像剤の穂だちと搬送量が得ら れた。 しかし、 磁性体口一ラーの重量は長さ 2 2 0Mで 0. 4 kg以上となり軽量化することはできず、 磁界の変 化に伴う濃度むらが顕著であつた。  A conventional one-component magnetic developing device that uses a developer transport member with an outer diameter of 20 OT and cuts a magnetic roller disposed inside it into an outer diameter of 18 OT and a thickness of 5 OT, and sintered sintered magnet. When the magnetic roller was divided into 8 poles or less and magnetized, a magnetic flux density of more than 500 gauss was obtained on the surface of the developer transfer member, and sufficient developer spikes and transfer amount were obtained. . However, the weight of the magnetic mouthpiece was 0.4 kg or more at a length of 220 M, and the weight could not be reduced, and the unevenness in concentration due to the change in the magnetic field was remarkable.
表面粗さの制御 Control of surface roughness
次に、 磁性体ローラーの表面粗さを制御する態様につ いて説明する。  Next, an embodiment for controlling the surface roughness of the magnetic roller will be described.
上述したような直接搬送型、 すなわち磁性体ローラー の表面において直接現像剤 （トナー） を搬送するタイプ の現像装置においては、 磁性体ローラー表面での トナー のフィ ルミ ング （つまり付着ないし固着） が比較的生じ やすいという問題がある。 このようなフイ ルミ ング現象 が生じると、 均一に帯電した トナー層を安定的に形成す ることが困難となり、 このため高品質な画像を長期間に わたって安定して形成することが困難となる。  In the case of the above-described direct transport type, that is, the developing device of the type in which the developer (toner) is directly transported on the surface of the magnetic roller, the filming (that is, adhesion or sticking) of the toner on the magnetic roller surface is compared. There is a problem that this is likely to occur. When such a filming phenomenon occurs, it is difficult to stably form a uniformly charged toner layer, and thus it is difficult to stably form a high-quality image for a long period of time. Become.
本発明においては、 前記磁性体ローラーの表面粗さを、 J I S規格の 1 0点平均粗さ （ J I S— B 0 6 0 1 ) の 表示に基づいて、 現像剤の構成要素である トナーの体積 平均粒子径の 4 0 %以下に制御することによって、 上記 の問題を効果的に解決することができる。 In the present invention, the surface roughness of the magnetic roller is defined as a 10-point average roughness (JIS-B0601) of JIS standard. The above problem can be effectively solved by controlling the volume average particle diameter of the toner, which is a component of the developer, to 40% or less based on the display.
上記のように、 表面粗さを厳格に制御することによつ てフイ ルミ ング現象を解消することができる理由は必ず しも明らかではないが、 磁性体ローラ一と現像剤搬送量 規制部材との間を トナーが通過する際に、 トナーと磁性 体ロー 一の接触部分に加えられる圧力ならびに摩擦力 が減少し、 これにより磁性体ローラー上への トナーのフ ，イ ルミ ングあるいは トナ一の劣化が抑制されるものと推 定される。  As described above, it is not always clear why the filming phenomenon can be eliminated by strictly controlling the surface roughness.However, the magnetic material roller and the developer transport amount regulating member are When the toner passes between the toner particles, the pressure and frictional force applied to the contact portion between the toner and the magnetic material roller are reduced, and as a result, deterioration of the toner on the magnetic material roller, the toner, or the toner is reduced. Is estimated to be suppressed.
一方、 表面粗さが上記の定義において 4 0 %未满の場 合は、 上述したようなフィルミ ング防止効果は乏しい。 なお、 上記の表面粗さの制御は、 前述したような、 凹凸 を形成した磁性体ローラーにおいても同様に適用され得 る o  On the other hand, if the surface roughness is less than 40% in the above definition, the above-described filming prevention effect is poor. Note that the above-described surface roughness control can be similarly applied to a magnetic roller having irregularities as described above.o
次に、 具体的な実施例に基づいて、 上記の態様につい て詳細に説明する。  Next, the above aspect will be described in detail based on specific examples.
実施例 C 1  Example C 1
本実施例においては、 カーボンブラッ ク、 F e 304 , ポリエステル樹脂を主たる構成要素とする体積平均粒子 怪 1 O ; m 0の磁性トナーによる 1成分現像剤を用いた《 前記構成の現像装置による画像形成装置において、 J I S規格 1 0点平均粗さ （ J I S — B 0 6 0 1 ) によ る表面粗さがそれぞれ異なる （ l〜1 0 /zmの範囲） 磁 性体ローラー 9を用いて、 それぞれ A4サイズ普通紙 50000枚相当の画像を連続して形成したところ、 磁 性体ローラー 9の J I S規格 1 0点平均粗さによる表面 粗さを 4 //mより大とした時に得られた画像には刷毛目 及び地被りが、 磁性体ローラー 9にはトナーによるフィ ラ ミ ングが明らかに認められたが、 磁性体ローラー 9の J I S¾ 格 10点平均粗さによる表面粗さが 4 iim以下 の時に得られた画像は刷毛目や地被りが認められない良 好な画像であり、 また磁性体ローラー 9にはトナーによ るフイ ノレミ ングは認められなかった。 In the present embodiment, carbon black click, F e 3 0 4, the volume average particle Kai 1 O to a polyester resin as a main component; using one-component developer according to the magnetic toner of the m 0 "developing device of the structure JIS standard 10 point average roughness (JIS-B0601) The surface roughness of each roller is different (in the range of l to 10 / zm). Using the magnetic roller 9, images of 50,000 sheets of A4 size plain paper were continuously formed. JIS standard 10 The image obtained when the surface roughness based on the 10-point average roughness is greater than 4 // m clearly shows brushing and ground covering, and the magnetic roller 9 clearly shows filming with toner. Although it was recognized, the image obtained when the surface roughness of the magnetic material roller 9 according to the JIS rating 10-point average roughness was 4 iim or less was a good image with no brushing or ground covering, and No fining by the toner was observed on the magnetic roller 9.
本実施例において用いた トナーの体積平均粒子径が l O m0であるから、 磁性体ローラー 9の J I S規格 1 0点平均粗さによる表面粗さが 4 wm以下の時、 すな わち磁性体ローラー 9の J I S 1 0点平均粗さによる 表面粗さがトナーの体積平均拉子径の 40 %以下の時に 良好な画像が得られる。  Since the volume average particle diameter of the toner used in this embodiment is lO m0, when the surface roughness of the magnetic roller 9 according to the JIS standard 10-point average roughness is 4 wm or less, that is, the magnetic material A good image can be obtained when the surface roughness of the roller 9 according to the JIS 10 point average roughness is 40% or less of the volume average diameter of the toner.
実施例 C 2  Example C 2
本実施例においては、 カーボンブラック、 ポリエステ ル樹脂を主たる構成要素とする体積平均粒子径 1 2 m øの トナーとキヤ リァである粒子径 1 00 m øの钦磁 性体粒子を混合した 2成分現像剤を用いた。  In the present embodiment, a two-component mixture of a toner having a volume average particle diameter of 12 mø, which is mainly composed of carbon black and a polyester resin, and magnetic particles having a particle diameter of 100 mø, which is a carrier, is mixed. A developer was used.
前記構成の現像装置による画像形成装置において、 J I S規格 10点平均粗さ （J I S— B 0601) によ る表面粗さがそれぞれ異なる磁性体ローラー 9を用いて、 それぞれ A 4サイズ普通紙 5 0 0 0 0枚相当の画像を連 続して形成したところ、 磁性体ローラー 9の J I S規格 1 0点平均粗さによる表面粗さを 4. 8 ;u mより大とし た時に得られた画像には刷毛目及び地被りが、 磁性体口 一ラー 9には トナーによるフィ ルミ ングが明らかに認め られたが、 磁性体ローラー 9の J I S規格 1 0点平均粗 さによる表面粗さが 4. 8 m以下の時に得られた画像 は刷毛目や地被りが認められない良好な画像であり、 ま ,た磁性体ローラー 9には トナーによるフイ ノレミ ングは認 められなかった。 In the image forming apparatus using the developing device having the above-described configuration, the image forming apparatus conforms to JIS standard 10-point average roughness (JIS-B0601). Using a magnetic roller 9 with different surface roughness, images of 500,000 sheets of A4 size plain paper were continuously formed, and the average of JIS standard 10 points of the magnetic roller 9 was obtained. Although the image obtained when the surface roughness due to the roughness was greater than 4.8 μm showed brushing and ground covering, and the magnetic material aperture 9 showed toner filming, The image obtained when the surface roughness according to the JIS standard 10-point average roughness of the magnetic roller 9 was 4.8 m or less was a good image in which no brushing or ground covering was observed. No fining with toner was observed on the body roller 9.
本実施例において用いた トナーの体積平均粒子径が  The volume average particle diameter of the toner used in this example is
1 2〃 m <iであるから、 磁性体ローラー 9の J I S規格 1 0点平均粗さによる表面粗さが 4. 8 /i m以下の時、 すなわち磁性体ローラー 9の J I S 1 0点平均粗さに よる表面粗さがトナーの体積平均粒子径の 4 0 %以下の 時に良好な画像が得られる。  Since 1 2〃 m <i, when the surface roughness according to the JIS standard 10 point average roughness of the magnetic roller 9 is 4.8 / im or less, that is, the JIS 10 point average roughness of the magnetic roller 9 When the surface roughness is 40% or less of the volume average particle diameter of the toner, a good image can be obtained.
実施例 C 3  Example C 3
本実施例においては、 カーボンブラ ック、 ワックス、 F e ¾ 04を主たる構成要素とする粒子をスチレン ♦ ァ ク リル系樹脂により被覆した体積苹均粒子径 9 β τη φの 磁性トナーによる 1成分現像剤を用いた。 In the present embodiment, carbon black click, waxes, by magnetic toner F e ¾ 0 volume 4 the particles as a main component was coated with styrene ♦ § click Lil resin苹均particle size 9 β τη φ 1 A component developer was used.
前記構成の現像装置による画像形成装置において、 J I S規格 1 0点平均粗さ （ J I S— B 0 6 0 1 ) によ る表面粗さがそれぞれ異なる磁性体ローラー 9を用いて、 それぞれ A 4サイズ普通紙 50000枚相当の画像を連 続して形成したところ、 磁性体ローラー 9の J I S規格 10点平均粗さによる表面粗さを 3. 6 mより大とし た時に得られた画像には刺毛目及び地被りが、 磁性体口 一ラー 9にはトナーによるフィルミ ングが明らかに認め られたが、 磁性体ローラー 9の J I S規格 1 0点平均粗 さによる'表面粗さが 3. 6 以下の時に得られた画像 は刷毛目や地被りが認められない良好な画像であり、 ま ,た磁性体口一ラー 9にはトナーによるフィ ルミ ングは認 められなかった。 In the image forming apparatus using the developing device having the above-mentioned configuration, the image forming apparatus is based on JIS standard 10 point average roughness (JIS-B0601). Using a magnetic roller 9 with different surface roughness, images of 50,000 sheets of A4 size plain paper were continuously formed, and the surface roughness of the magnetic roller 9 according to the JIS standard 10-point average roughness was obtained. In the image obtained when the height was larger than 3.6 m, stitches and ground covering were clearly observed in the image of the magnetic material opening 9, and filming with toner was clearly observed in the magnetic opening 9. The image obtained when the surface roughness according to JIS standard 10-point average roughness is 3.6 or less is a good image with no brushing or ground covering, and the magnetic material aperture 9 No filming with toner was observed.
本実施例において用いた トナーの体積平均泣子径が 9 であるから、 磁性体ローラー 9の J I S規格 1 0 点平均粗さによる表面粗さが 3. 6 m以下の時、 すな わち磁性体ローラー 9の J I S 10点平均粗さによる 表面粗さがトナ一の体積平均粒子瘙の 40 %以下の時に 良好な画像が得られる。  Since the volume average diameter of the toner used in the present embodiment is 9, the magnetic roller 9 has a surface roughness of 3.6 m or less according to the JIS standard 10-point average roughness, that is, the magnetic property. A good image can be obtained when the surface roughness of the body roller 9 according to JIS 10 point average roughness is 40% or less of the volume average particle size of the toner.
腐食防止層の形成  Formation of corrosion prevention layer
前述したように、 磁性体ローラーの磁石材料としては、 フェライ ト、 アルニコ、 マンガンアルミ、 希土類磁石等 の公知の磁石材料を使用することができるが、 特に原子 番号 58〜7 1 (元素記号 C e〜L u) に至る 14種類 の希土類元素、 その中でも N d、 P r及び S mに代表さ れる希土類元素の少なく とも 1つに、 F e、 N i及び C oに代表される 3 d遷移金属の少なく とも 1つを加え た希土類磁石を使用することが望ま しい。 しかしながら、 特に F eを含有するような希土類磁石を含む磁性体ロー ラーを用いた場合、 空気中の酸素あるいは水分等の影響 により前記磁性体ローラー表面に酸化腐食 （いわゆるサ ビ） が発生するために、 高品質な画像を長期間安定して 形成することができないという問題が生じる場合がある。 本発 の現像装置においては、 磁性体ローラーの表面 に被覆層を設ける （少なく とも磁性体ローラーの現像剤 搬送面において磁石の露出がないように被覆される） こ とにより、 希土類磁石を用いた場合においても空気中の 酸素あるいは水分等の影響により前記磁性体ローラー表 面に酸化腐食が発生することがないために、 高品質な画 像を長期間安定して形成することが可能となる。 As described above, known magnetic materials such as ferrite, alnico, manganese aluminum, and rare earth magnets can be used as the magnetic material for the magnetic roller, and in particular, atomic numbers 58 to 71 (element symbol C e ~ Lu), at least one of the rare earth elements represented by Nd, Pr and Sm, Fe, Ni and It is desirable to use a rare earth magnet to which at least one of the 3d transition metals represented by Co is added. However, especially when a magnetic roller containing a rare earth magnet containing Fe is used, oxidative corrosion (so-called rust) occurs on the surface of the magnetic roller due to the influence of oxygen or moisture in the air. In addition, there may be a problem that a high-quality image cannot be stably formed for a long period of time. In the developing device of the present invention, a rare earth magnet is used by providing a coating layer on the surface of the magnetic roller (at least being coated so that the magnet is not exposed on the developer transport surface of the magnetic roller). In this case, oxidative corrosion does not occur on the surface of the magnetic roller due to the influence of oxygen or moisture in the air, so that a high-quality image can be stably formed for a long period of time.
本発明における被覆層 （図示せず） としては、 磁性体 ローラー 9の表面を磁石 1 2の露出がないように被覆で きる材料であればすべて使用することが可能であり、 例 えば、 A l、 N i、 A u、 P t等の非鉄金属、  As the coating layer (not shown) in the present invention, any material can be used as long as it can cover the surface of the magnetic roller 9 so that the magnets 12 are not exposed. , Ni, Au, Pt, etc.
F e 3 、 S i 0 2等の無機酸化物、 ポリカーボネー ト、 ポリスチレン等の樹脂等を用いることが可能である。 また、 被覆層の膜厚としては、 被覆層形成時におけるビ ンホール等の欠陷の発生防止や長期間の使用における被F e 3, S i 0 inorganic oxides such as 2, Polycarbonate, it is possible to use a resin such as polystyrene or the like. In addition, the thickness of the coating layer is determined to prevent the occurrence of defects such as via holes during the formation of the coating layer and to prevent the coating layer from being used for a long time.
¾層劣化防止等の観点から、 1 m以上の胰厚が望ま し い。 実施例 D l From the viewpoint of preventing layer deterioration, a thickness of 1 m or more is desirable. Example Dl
本実施例においては、 磁性体ローラー 9としてネオジ ゥム ♦鉄系焼結磁石を用い、 さらに被覆層として磁性体 ローラー 9の表面をエポキシ樹脂により被覆した構成と した。  In this embodiment, a neodymium iron-based sintered magnet was used as the magnetic roller 9, and the surface of the magnetic roller 9 was coated with an epoxy resin as a coating layer.
前記構成の現像装置による画像形成装置を用いて、 温 度 3 0で、 相対湿度 6 0 %の環境下において A 4サイズ 普通紙 5 0 0 0 0枚相当の画像を連铳して形成したが、 得られた画像の劣化は認められず、 印字 1枚目と同様に ，解像度の高い高品質な画像が得られた。 また、 磁性体口 一ラー 9の表面の酸化腐食は認められず、 磁性体ローラ 一 9上には安定的に均一な厚さの現像剤層が形成されて いた。  Using an image forming apparatus with the developing device having the above-described configuration, an image corresponding to 500,000 sheets of A4 size plain paper was continuously formed under an environment of a temperature of 30 and a relative humidity of 60%. However, no deterioration of the obtained image was observed, and a high-resolution, high-quality image was obtained as in the case of the first printed sheet. No oxidative corrosion was observed on the surface of the magnetic material roller 9, and a developer layer having a uniform thickness was formed stably on the magnetic material roller 19.
比蛟例 D 1  Comparative example D 1
磁性体ローラー 9の表面をエポキシ樹脂により被覆せ ずに磁石 1 2が露出している以外は実施例 D 1 と同様な 構成の現像装置による画像形成装置を用いて、 実施例 D 1 と同様の環境下において A 4サイズ普通紙 5 0 0 0 0 枚相当の画像を連続して形成したところ、 得られた画像 には刷毛目等のかすれや地被り等の劣化が認められ、 ま た、 磁性体ローラー 9の表面には酸化腐食が認められた, 実施例 D 2  An image forming apparatus using a developing device having the same configuration as that of Example D1 except that the surface of the magnetic roller 9 was not covered with the epoxy resin and the magnets 12 were exposed, was used in the same manner as in Example D1. When an image equivalent to 500 000 sheets of A4 size plain paper was continuously formed under the environment, the obtained image showed blurring such as brushes and deterioration of ground covering, etc. Oxidation corrosion was observed on the surface of body roller 9, Example D 2
本実施例においては、 磁性体ローラー 9としてネオジ ゥム ·鉄系焼結磁石を用い、 さらに被覆層として磁性体 ローラー 9の表面を N i により被覆 （N i メ ツキ） した 構成とした。 In this embodiment, a neodymium-iron sintered magnet is used as the magnetic roller 9, and a magnetic material is used as the coating layer. The surface of the roller 9 was covered with Ni (Ni plating).
前記構成の現像装置による画像形成装置を用いて、 実 施例 D 1 と同様の環境下において A 4サイズ普通紙  Using an image forming apparatus with the developing device having the above-described configuration, A4 size plain paper was used in the same environment as in Example D1.
5 0 0 0 0枚相当の画像を連続して形成したが、 得られ た画像の劣化は認められず、 印字 1枚目と同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表 ®の酸化腐食は認められず、 磁性体ローラー 9上 には安定的に均一な厚さの現像剤層が形成されていた。 , 比較例 D 2  Although an image corresponding to 500,000 sheets was continuously formed, no deterioration of the obtained image was observed, and a high-quality image with high resolution was obtained as in the first print. Further, no oxidative corrosion was observed on the surface of the magnetic roller 9, and a developer layer having a uniform thickness was formed on the magnetic roller 9 stably. , Comparative Example D 2
磁性体ローラー 9の表面を N i により被 Sせずに磁石 1 2が露出している以外は実施例 D 2と同様な構成の現 像装置による画像形成装置を用いて、 実施例 D 1 と同様 の環境下において A 4サイズ普通紙 5 0 0 0 0枚相当の 画像を連続して形成したところ、 得られた画像には刷毛 目等のかすれや地被り等の劣化が認められ、 また、 磁性 体ローラー 9の表面には酸化腐食が認められた。  Example D1 was repeated using an image forming apparatus having a configuration similar to that of Example D2 except that the magnet 12 was exposed without covering the surface of the magnetic roller 9 with Ni. Under the same environment, when an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, the obtained image showed blurring of brush eyes and deterioration of ground covering, etc. Oxidation corrosion was observed on the surface of the magnetic roller 9.
実施例 D 3 '  Example D 3 '
本実施例においては、 磁性体ローラー 9としてネオジ ゥム ·鉄系焼結磁石を用い、 さらに被覆雇として磁性体 ローラー 9の表面を S i 0 2により被覆した構成とした。 前記構成の現像装置による画像形成装置を用いて、 実 施例 D 1同様の環境下において A 4サイズ普通紙 In this embodiment, a neodymium-iron sintered magnet was used as the magnetic roller 9, and the surface of the magnetic roller 9 was coated with SiO 2 as a coating. Using an image forming apparatus including the developing device having the above-described configuration, A4 size plain paper under the same environment as in Example D1.
5 0 0 0 0枚相当の画像を連銃して形成したが、 得られ た画像の劣化は認められず、 印字 1枚目と同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面の酸化腐食は認められず、 磁性体ローラー 9上 には安定的に均一な厚さの現像剤層が形成されていた。 比较例 D 3 An image equivalent to 500 000 sheets was formed by successive guns. No deterioration of the image was observed, and a high-resolution, high-quality image was obtained as in the first print. Further, no oxidative corrosion was observed on the surface of the magnetic roller 9, and a developer layer having a uniform thickness was formed stably on the magnetic roller 9. Comparative example D 3
磁性体ローラー 9の表面を S i 0 2により披 Sせずに 磁石 1 2が露出している以外は実施例 D 3と同様な構成 の現像装置による画像形成装置を用いて、 実施例 D 1と 同様の環境下において A 4サイズ普通紙 5 0 0 0 0枚相 ，当の画像を連銃して形成したところ、 得られた画像には 刷毛目等のかすれや地被り等の劣化が認められ、 また、 磁性体ローラー 9の表面には酸化腐食が認められた。 The surface of the magnetic roller 9 by using the image forming apparatus according to the developing apparatus having the same construction as in Example D 3 except that the magnet 1 2 without披S by S i 0 2 is exposed, Example D 1 Under the same environment as above, A4 size plain paper 50,000 sheets, and the corresponding images were formed by continuous shooting. The resulting images showed blurring such as brushing and deterioration of ground covering. Oxidation corrosion was observed on the surface of the magnetic roller 9.
実施例 D 4  Example D 4
本実施例においては、 磁性体ローラー 9としてネオジ ゥム ·鉄系焼結磁石を用い、 さらに被覆餍として磁性体 ローラー 9の表面を T i 0 2により被覆した搆成とした。 前記構成の現像装置による画像形成装置を用いて、 実 施例 D 1と同様の環境下において A 4サイズ普通紙 In the present embodiment, using the neodymium ©-time iron-based sintered magnet as magnetic roller 9, the surface of the magnetic roller 9 was搆成covered by T i 0 2 as further coated餍. Using an image forming apparatus with the developing device having the above-described configuration, A4 size plain paper was used in the same environment as in Example D1.
5 0 0 0 0枚相当の画像を連鎵して形成したが、 得られ た画像の劣化は認められず、 印字 1枚目と同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面の酸化腐食は認められず、 磁性体ローラー 9上 には安定的に均一な厚さの現像剤層が形成されていた。 - 1 — 比較例 D 4 Although an image corresponding to 5,000 sheets was continuously formed, no deterioration of the obtained image was observed, and a high-quality image with high resolution was obtained as in the case of the first printed sheet. Further, no oxidative corrosion was observed on the surface of the magnetic roller 9, and a developer layer having a uniform thickness was formed stably on the magnetic roller 9. -1 — Comparative example D 4
磁性体ローラー 9の表面を T i 0 2により被覆せずに 磁石が露出している以外は実施例 D 4 と同様な構成の現 像装置による画像形成装置を用いて、 実施例 D 1 と同様 の環境下において A 4サイズ普通紙 5 0 0 0 0枚相当の 画像を連続して形成したところ、 得られた画像には刷毛 目等のかすれや地被り等の劣化が認められ、 また、 磁性 体ロー 一 9の表面には酸化腐食が認められた。 Except that the magnet surface of the magnetic roller 9 uncovered by T i 0 2 is exposed with an image forming apparatus according to the current image device having the same structure as in Example D 4, as in Example D 1 In this environment, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, and the obtained image showed blurring of brush eyes and deterioration of ground covering, etc. Oxidative corrosion was observed on the surface of body ro-1-9.
実施例 D 5  Example D 5
, 本実施例においては、 磁性体ローラー 9としてブラセ ォジゥム ♦鉄系铸造磁石を用い、 さらに被覆雇と して磁 性体ローラー 9の表面を S i Cにより被覆した構成とし 前記構成の現像装置による画像形成装置を用いて、 実 施例 D 1同様の環境下において A 4サイズ普通紙 However, in this embodiment, a brassium iron-based magnet is used as the magnetic roller 9, and the surface of the magnetic roller 9 is coated with SiC as a coating. Using an image forming apparatus, A4 size plain paper under the same environment as in Example D1
5 0 0 0 0枚相当の画像を連銃し" 形成したが、 得られ た画像の劣化は認められず、 印字 1枚目と同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面の酸化腐食は認められず、 磁性体ローラー 9上 には安定的に均一な厚さの現像剤層が形成されていた。 比較例 D 5  An image equivalent to 500,000 sheets was repeatedly fired and formed. However, no deterioration of the obtained image was observed, and a high-resolution, high-quality image was obtained similarly to the first print. No oxidative corrosion was observed on the surface of the magnetic roller 9, and a developer layer having a uniform thickness was formed stably on the magnetic roller 9. Comparative Example D5
磁性体ローラー 9の表面を S i Cにより被 Sせずに磁 石 1 2が露出している以外は実施例 D 5と同様な構成の 現像装置による画像形成装置を用いて、 実施例 D 1 と同 様の環境下において A 4サイズ普通紙 5 0 0 0 0枚相当 の画像を連続して形成したところ、 得られた画像には刷 毛目等のかすれや地被り等の劣化が認められ、 また、 磁 性体ローラー 9の表面には酸化腐食が認められた。 Example D1 was performed using an image forming apparatus using a developing device having the same configuration as that of Example D5 except that the magnet 12 was exposed without covering the surface of the magnetic roller 9 with SiC. Same as Under the same environment, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, and the resulting image showed blurring such as brushing and deterioration of ground covering. However, oxidation corrosion was observed on the surface of the magnetic roller 9.
実施例 D 6  Example D 6
本実施例においては、 磁性体ローラー 9としてプラセ ォジゥム ，鉄系铸造磁石を用い、 さらに被 S雇として磁 性体ロニラー 9の表面を A 1 2 0 3により被覆した構成 とした。 In the present embodiment, Purase Ojiumu, the iron-based铸造magnet used as the magnetic body roller 9, the surface of the magnetic material element Ronira 9 has a structure covered by A 1 2 0 3 as a further object S employment.
, 前記構成の現像装置による画像形成装置を用いて、 実 施例 D 1同様の環境下において A 4サイズ普通紙 Using an image forming apparatus having the developing device having the above-described configuration, A4 size plain paper was produced under the same environment as in Example D1.
5 0 0 0 0枚相当の画像を連続して形成したが、 得られ た画像の劣化は認められず、 印字 1枚目と同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面の酸化腐食は認められず、 磁性体ローラー 9上 には安定的に均一な厚さの現像剤詹が形成されていた。 比較例 D 6  Although an image corresponding to 500,000 sheets was continuously formed, no deterioration of the obtained image was observed, and a high-quality image with high resolution was obtained as in the first print. Further, no oxidative corrosion was observed on the surface of the magnetic roller 9, and the developer の having a stable and uniform thickness was formed on the magnetic roller 9. Comparative Example D 6
磁性体ローラー 9の表面を A 1 0 3により被覆せず に磁石 1 2が露出している以外は実施例 D 6と同様な構 成の現像装置による画像形成装置を用いて、 実施例 D 1 と同様の環境下において A 4サイズ普通紙 5 0 0 0 0枚 相当の画像を連続して形成したところ、 得られた画像に は刷毛目等のかすれや地被り等の劣化が認められ、 また 磁性体ローラー 9の表面には酸化腐食が認められた。 実施例 D 7 The surface of the magnetic roller 9 by using the image forming apparatus according to the developing apparatus is similar configurations to Example D 6 except that exposed magnet 1 2 uncovered by A 1 0 3, Example D 1 Under the same environment as above, when images equivalent to 500,000 sheets of A4 size plain paper were continuously formed, the obtained images showed blurring such as brushes and deterioration of ground covering, etc., and Oxidation corrosion was observed on the surface of the magnetic roller 9. Example D 7
本実施例においては、 磁性体ローラー 9と してプラセ ォジゥム ♦鉄系铸造磁石を用い、 さらに被覆靥として磁 性体ローラー 9の表面を Ζ π Οにより被覆した構成とし 前記構成の現像装置による画像形成装置を用いて、 実 施例 D 1同様の環境下において A 4サイズ普通紙  In the present embodiment, a magnetic material roller 9 is made of a plastic magnet, and an iron-based artificial magnet is used, and the magnetic material roller 9 is coated with {π} as a coating. A4 size plain paper in the same environment as in Example D 1 using a forming apparatus
5 0 0 0 0枚相当の画像を連続して形成したが、 得られ た画像の劣化は認められず、 印字 1枚目と同様に解像度 ,の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面の酸化腐食は認められず、 磁性体ローラー 9上 には安定的に均一な厚さの現像剤層が形成されていた。 比較例 D 7  Although an image corresponding to 5,000 sheets was continuously formed, no deterioration of the obtained image was observed, and a high-quality image with high resolution and high resolution was obtained as in the first print. Further, no oxidative corrosion was observed on the surface of the magnetic roller 9, and a developer layer having a uniform thickness was formed stably on the magnetic roller 9. Comparative Example D 7
磁性体ローラー 9の表面を Z n 0により被 ¾せずに磁 石 1 2が露出している以外は実施例 D 7と同様な構成の 現像装置による画像形成装置を用いて、 実施例 D 1 と同 様の環境下において A 4サイズ普通紙 5 0 0 0 0枚相当 の画像を連続して形成したところ、 得られた画像には刷 毛目等のかすれや地被り等の劣化が認められ、 また、 磁 性体ローラー 9の表面には酸化腐食が認められた。  Example D1 was performed using an image forming apparatus using a developing device having the same configuration as that of Example D7 except that the magnet 12 was exposed without covering the surface of the magnetic material roller 9 with Zn0. Under the same environment as above, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, and the resulting image showed blurring such as brushing and deterioration of ground covering. Oxidation corrosion was observed on the surface of the magnetic roller 9.
実施例 D 8  Example D 8
本実施例においては、 磁性体ローラー 9としてプラセ ォジゥム ·鉄系押出成形磁石を用い、 さらに被覆雇と し て磁性体口一ラー 9の表面を A 1 により被覆した構成と した。 In this embodiment, a magnetic roller 9 is made of extruded magnet made of a place iron or an iron-based magnet, and the surface of the magnetic opening 9 is coated with A 1 as a coating. did.
前記構成の現像装置による画像形成装置を用いて、 実 施例 D 1同様の環境下において A 4サイズ普通紙  Using an image forming apparatus including the developing device having the above-described configuration, A4 size plain paper under the same environment as in Example D1.
5 0 0 0 0枚相当の画像を連続して形成したが、 得られ た画像の劣化は認められず、 印字 1枚目と同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面の酸化腐食は認められず、 磁性体ローラー 9上 には安 的に均一な厚さの現像剤雇が形成されていた。 比蛟例 D 8  Although an image corresponding to 500,000 sheets was continuously formed, no deterioration of the obtained image was observed, and a high-quality image with high resolution was obtained as in the first print. Further, no oxidative corrosion was observed on the surface of the magnetic roller 9, and a uniform thickness of the developer was formed on the magnetic roller 9. Comparative example D 8
f 磁性体ローラー 9の表面を A 1 により被覆せずに磁石 1 2が露出している以外は実施例 D 8と同様な構成の現 像装置による画像形成装置を用いて、 実施例 D 1 と同様 の環境下において A 4サイズ普通紙 5 0 0 0 0枚相当の 画像を連続して形成したところ、 得られた画像には刷毛 目等のかすれや地被り等の劣化が認められ、 また、 磁性 体ローラー 9の表面には酸化腐食が認められた。 f Using the image forming apparatus having the same configuration as in Example D8 except that the magnet 12 is exposed without covering the surface of the magnetic roller 9 with A1, Under the same environment, when an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, the obtained image showed blurring of brush eyes and deterioration of ground covering, etc. Oxidation corrosion was observed on the surface of the magnetic roller 9.
実施例 D 9  Example D 9
本実施例においては、 磁性体ローラ一 9としてサマリ ゥム ， コバルト系押出成形磁石を用い、 さらに被覆層と して磁性体ローラー 9の表面を N i により被覆した構成 とした。  In the present embodiment, a magnet and a cobalt-based extruded magnet were used as the magnetic roller 19, and the surface of the magnetic roller 9 was coated with Ni as a coating layer.
前記構成の現像装置による画像形成装置を用いて、 実 施例 D 1同様の環境下において A 4サイズ普通紙  Using an image forming apparatus including the developing device having the above-described configuration, A4 size plain paper under the same environment as in Example D1.
5 0 0 0 0枚相当の画像を連銃して形成したが、 得られ た画像の劣化は認められず、 印字 1枚目と同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面の酸化腐食は認められず、 磁性体ローラー 9上 には安定的に均一な厚さの現像剤層が形成されていた。 比較例 D 9 An image equivalent to 500 000 sheets was formed by successive guns. No deterioration of the image was observed, and a high-resolution, high-quality image was obtained as in the first print. Further, no oxidative corrosion was observed on the surface of the magnetic roller 9, and a developer layer having a uniform thickness was formed stably on the magnetic roller 9. Comparative Example D 9
磁性体ローラー 9の表面を N i により被 Sせずに磁石 1 2が露出している以外は実施例 D 9と同様な構成の現 像装置 よる画像形成装置を用いて、 実施例 D 1 と同様 の環境下において A 4サイズ普通紙 5 0 0 0 0枚相当の ,画像を連続して形成したところ、 得られた画像には刷毛 目等のかすれや地被り等の劣化が認められ、 また、 磁性 体ローラー 9の表面には酸化腐食が認められた。  Example D1 was performed using an image forming apparatus having a configuration similar to that of Example D9 except that the magnet 12 was exposed without covering the surface of the magnetic roller 9 with Ni. Under the same environment, when images of A4 size plain paper 500 000 sheets were continuously formed, the obtained images showed blurring such as brush eyes and deterioration of ground covering, etc. However, oxidation corrosion was observed on the surface of the magnetic roller 9.
実施例 D 1 0  Example D 10
本実施例においては、 磁性体ローラー 9と してサマリ ゥム · コバルト系圧縮成形磁石を用い、 さ らに被 ¾層と して磁性体ローラー 9の表面を T i 0 2により被 ¾した 構成とした。 In the present embodiment, using the summary ©-time cobalt compression molded magnet as a magnetic roller 9, as an object to be ¾ layer is al the surface of the magnetic roller 9 and the ¾ by T i 0 2 configuration And
前記構成の現像装置による画像形成装置を用いて、 実 施例 D 1同様の環境下において A 4サイズ普通紙  Using an image forming apparatus including the developing device having the above-described configuration, A4 size plain paper under the same environment as in Example D1.
5 0 0 0 0枚相当の画像を連続して形成したが、 得られ た画像の劣化は認められず、 印字 1枚目と同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面の酸化腐食は認められず、 磁性体ローラー 9上 には安定的に均一な厚さの現像剤層が形成されていた。 比較例 D 1 0 Although an image corresponding to 500,000 sheets was continuously formed, no deterioration of the obtained image was observed, and a high-quality image with high resolution was obtained as in the first print. Further, no oxidative corrosion was observed on the surface of the magnetic roller 9, and a developer layer having a uniform thickness was formed stably on the magnetic roller 9. Comparative Example D 10
磁性体ローラー 9の表面を T i 0 2により被覆せずに 磁石 1 2が露出している以外は実施例 D 1 0と同様な構 成の現像装置による画像形成装 gを用いて、 実施例 D 1 と同様の環境下において A 4サイズ普通紙 5 0 0 0 0枚 相当の画像を連铳して形成したところ、 得られた画像に は刷毛目等のかすれや地被り等の劣化が認められ、 また、 磁性体ローラー 9の表面には酸化腐食が認められた。 Except that the magnet 1 2 is exposed without the surface of the magnetic roller 9 was coated with T i 0 2 by using the image forming instrumentation g by the developing apparatus having the same configuration as in Example D 1 0, Example Under the same environment as D1, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, and the resulting image showed blurring such as brushing and deterioration of ground covering. Oxidation corrosion was observed on the surface of the magnetic roller 9.
樹脂層の形成  Formation of resin layer
, 本発明のような直接搬送型の現像装置においては、 磁 性体ローラーの表面と現像剤との間の摩擦帯電、 現像剤 と現像剤との間の摩擦帯電、 現像剤搬送量規制部材等の 現像装置の構成要素と現像剤との間の摩擦帯電等の様々 な帯電機構により、 個々の現像剤の有する帯電量は大き く異なる。 このような帯電機構の相違に基因して帯電量 分布のブロー ドな現像剤が前記磁&体ローラー上に搬送 される結果となり、 このため得られる画像は非常に画質 の低いものとなってしまうというおそれがある。 In a direct transport type developing device such as the present invention, frictional charging between the surface of the magnetic roller and the developer, frictional charging between the developer and the developer, developer transport amount regulating member, etc. Due to various charging mechanisms such as frictional charging between the components of the developing device and the developer, the amount of charge of each developer greatly differs. Due to such a difference in the charging mechanism, the developer having a broad charge amount distribution is conveyed onto the magnetic roller and the resulting image has a very low image quality. There is a possibility that.
本発明の現像装置においては、 磁性体ローラーの表面 に少なく とも 1種類の樹脂からなる被覆層を設けること により、 上記の問題を解消することができる。 すなわち、 前記磁性体ローラー上に搬送される現像剤に対して、 前 記被覆された樹脂層が、 あたかも 2成分現像剤の構成要 素であるキャ リアのように作用して、 摩擦蒂電による現 像剤の帯電を規制し、 この作用によって現像剤の帯電量 分布を均一なものとし、 ひいては高品質な画像を安定し て形成することが可能となる。 In the developing device of the present invention, the above problem can be solved by providing a coating layer made of at least one kind of resin on the surface of the magnetic roller. That is, the coated resin layer acts on the developer conveyed on the magnetic roller as if it were a carrier that is a component of a two-component developer. Present By regulating the charging of the imaging agent, this action makes the distribution of the charging amount of the developer uniform, and as a result, a high-quality image can be stably formed.
また、 前記被 S層がフッ素あるいは珪素の少なく とも どちらか一方を含む榭脂を含むことにより、 前記磁性体 ローラーの表面への現像剤のフィ ルミ ング （固着あるい は融着） が防止され、 前記磁性体ローラーの表面を長期 間安定 に清浄に保つことができ、 ひいては高品質な画 像を長期間安定して形成することが可能となる。  Further, since the S layer contains a resin containing at least one of fluorine and silicon, filming (fixing or fusing) of the developer on the surface of the magnetic roller is prevented. In addition, the surface of the magnetic roller can be stably and cleanly maintained for a long period of time, so that a high-quality image can be stably formed for a long period of time.
, 本実施例においては、 被覆層 （樹脂層） が磁性体ロ ー ラー 9の表面を完全にあるいは均一に被覆する例を示し たが、 これは本発明を限定するものではなく、 被 S層の 膜厚は不均一であってもよく、 磁石 （磁性体ローラーの 表面） が露出する不完全な被覆であってもよく、 被覆屨 が連続的なものではなく樹脂の島が多数独立して磁性体 ローラー 9の表面に形成されてい δものであってもよい。 また、 本発明においては、 1成分磁気ブラシ現像剤及 び 2成分磁気ブラシ現像剤と して公知の現像剤ならばす ベて使用可能であり、 被覆層を構成する樹脂を適当に選 択することにより、 現像剤 8の帯電極性を正極あるいは 負極のどちらの極性であつても所望の極性に制御するこ とが可能である。 尚、 現像剤 8の帯電性の制御を被 S層 により行うにあたっては上記のように被覆雇を構成する 樹脂の選択が重要であるが、 現像剤 8とし T 1成分現像 剤を用いるプロセスでは、 現像剤 8中に帯電制御剤が混 合されている場合に帯電制御剤による帯電効果を最大限 に発揮させるためには現像剤 8を構成する樹脂と蒂電系 列の同等な樹脂を用いることが望ましく、 現像剂 8中に 帯 ¾制御剤が混合されているが帯電制御剂では充分な帯 電が得られないあるいは遏剰帯電してしまう場合には現 像剤 8を構成する樹脂に対して蒂電制御剤による帯電効 果を補強あるいは抑制する帯電系列の褂脂を用いること が望ましく、 本発明が特に効果を発揮する場合である現 ,像剂 8中に帯電制御剤が混合されていない場合には現像 剤 8を構成する樹脂に対して所望する帯電量が得られる 帯電系列の樹脂を用いることが望ましく、 現像剤 8とし て 2成分現像剤を用いるプロセスでも全く同様に被 S層 を構成する樹脂を選択すればよいが、 帯電量分布を均一 にするという観点からはキヤ リアあるいはキヤ リァ表面 を被覆する榭脂に対して帯電系列め同等な樹脂を用いる ことが特に望ま しい。 In this embodiment, an example in which the coating layer (resin layer) completely or uniformly covers the surface of the magnetic roller 9 has been described. However, this is not intended to limit the present invention. The coating thickness may be non-uniform, or the coating may be incomplete, exposing the magnet (the surface of the magnetic roller). The coating is not continuous, and many resin islands are formed independently. It may be δ formed on the surface of the magnetic roller 9. Further, in the present invention, any known developer can be used as the one-component magnetic brush developer and the two-component magnetic brush developer, and the resin constituting the coating layer is appropriately selected. Accordingly, it is possible to control the charged polarity of the developer 8 to a desired polarity regardless of the polarity of the positive electrode or the negative electrode. In order to control the chargeability of the developer 8 by using the S layer, it is important to select the resin constituting the coating as described above. In the process using the developer, when the charge control agent is mixed in the developer 8, in order to maximize the charging effect of the charge control agent, the resin constituting the developer 8 and the resin It is desirable to use an equivalent resin, and when a charging agent is mixed in the developing agent 8, but sufficient charging cannot be obtained or charging is insufficient under the charging control agent, the developing agent 8 is used. It is desirable to use a charging series of resin that reinforces or suppresses the charging effect of the dyden control agent on the resin constituting the resin, and the present invention is particularly effective when charging is performed during image formation. When the control agent is not mixed, it is desirable to use a resin of a charging series which can obtain a desired amount of charge with respect to the resin constituting the developer 8, even in a process using a two-component developer as the developer 8. Configure the S layer in exactly the same way It may be selected fat, but charge quantity distribution from the viewpoint of uniform be used equivalent resins Me triboelectric series relative 榭脂 coating the wire carrier rear or wire carrier Ria surface particularly desirable arbitrariness.
実施例 E 1  Example E 1
本実施例においては、 磁性体ローラー 9としてフユラ ィ ト系焼結磁石を用い、 被覆屈 （樹脂屐） として、 ポリ エステル樹脂による （多数の独立した） 島状の被覆雇を 形成した。  In this embodiment, a sintered sintered magnet was used as the magnetic roller 9 and (a large number of independent) island-shaped covering members made of a polyester resin were formed as the covering flex (resin scoop).
前記構成の現像装置による画像形成装置を用いて、 A 4サイズ普通紙 5 0 0 0枚相当の画像を連続して形成 したが、 得られた画像は印字 1枚目と同様に高解像度か っ高浪度で高品質な画像が得られた。 Using an image forming apparatus including the developing device having the above-described configuration, an image equivalent to 500 sheets of A4 size plain paper is continuously formed. However, the obtained image was a high-resolution, high-robustness and high-quality image, similar to the first printed sheet.
比較例 E 1  Comparative Example E 1
磁性体ローラー 9の表面に被逭屨がないこと以外は実 施例 E 1 と同様な構成の現像装置による画像形成装置を 用いて、 同様の条件下に於て画像を連続して形成したと ころ、 得られた画像は画像瑭度が低くかつ'濃度ムラが認 められる低画質の画像であつた。  An image was continuously formed under the same conditions using an image forming apparatus having a developing device having the same configuration as that of Example E1 except that the surface of the magnetic roller 9 was not covered. At this time, the obtained image was a low-quality image with low image intensity and uneven density.
実施例 E 2  Example E 2
本実施例においては、 磁性体ローラ一 9と してサマリ ゥムコバルト系押出成形磁石を用い、 被覆餍として、 ポ リカーボネー ト樹脂による （多数の独立した） 島状の被 覆層を形成した。  In this example, a summary cobalt-based extruded magnet was used as the magnetic roller 19, and a (many independent) island-like coating layer made of polycarbonate resin was formed as the coating.
前記構成の現像装置による画像形成装匿を用いて、 A 4サイズ普通紙 5 0 0 0枚相当の画像を連铳して形成 したが、 得られた画像は印字 1枚目と同様に髙解像度か つ高濃度で高品質な画像が得られた。  Using an image forming and concealing method using the developing device having the above-described configuration, images equivalent to 500 sheets of A4 size plain paper were continuously formed, but the obtained image had the same resolution as the first sheet of printing. High quality images with high density were obtained.
比铰例 E 2  Comparative example E 2
磁性体ローラー 9の表面に被覆層がないこと以外は実 施例 E 2と同様な構成の現像装置による画像形成装置を 用いて、 同様の条件下に於て画像を連続して形成したと ころ、 得られた画像は画像濃度が低く かつ濃度ムラが認 められる低画質の画像であった。 実施例 E 3 An image was continuously formed under the same conditions using an image forming apparatus having the same configuration as that of Example E2 except that the surface of the magnetic material roller 9 had no coating layer. The obtained image was a low-quality image with low image density and uneven density. Example E 3
本実施例においては、 磁性体ローラー 9としてネオジ ゥム ·鉄系焼結磁石を用い、 被覆層としてポリイ ミ ド樹 脂により均一な （磁石の露出のない） 被覆層を形成した。 前記構成の現像装匿による画像形成装 Sを用いて、 A 4サイズ普通紙 5 0 0 0枚相当の画像を連蜣して形成 したが、 得られた画像は印字 1枚目と同様に高解像度か つ高港度で高品質な画像が得られた。  In this example, a neodymium-iron sintered magnet was used as the magnetic roller 9, and a uniform (non-exposed magnet) coating layer was formed with polyimide resin as the coating layer. Using the image forming apparatus S with developing and concealment of the above configuration, images equivalent to 500 sheets of A4 size plain paper were continuously formed, but the obtained image was as high as the first sheet of printing. High quality images with high resolution and high port were obtained.
比較例 E 3  Comparative Example E 3
磁性体ローラー 9の表面に被覆層がないこと以外は実 施例 E 3と同様な構成の現像装置による画像形成装置を 用いて、 同様の条件下に於て画像を連続して形成したと ころ、 得られた画像は画像濃度が低くかつ濃度ムラが認 められる低画質の画像であつた。  An image was continuously formed under the same conditions using an image forming apparatus using a developing device having the same configuration as that of Example E3 except that there was no coating layer on the surface of the magnetic roller 9. The obtained image was a low-quality image with low image density and uneven density.
実施例 E 4  Example E 4
本実施例においては、 磁性体ローラー 9としてネオジ ゥム ·鉄系焼結磁石を用い、 被覆層としてシリ コーン榭 脂 （有機シラ ン樹脂） により均一な （磁石の露出のない） 被覆層を形成した。  In this embodiment, a neodymium-iron sintered magnet is used as the magnetic roller 9, and a uniform (non-exposed magnet) coating layer is formed with silicone resin (organic silane resin) as the coating layer. did.
前記構成の現像装置による画像形成装置を用いて、 A 4サイズ普通紙 5 0 0 0 0枚相当の画像を連続して形成 したが、 得られた画像は印字 1枚目と同様に高解像度か つ高港度で高品質な画像が得られた。 また、 磁性体ロー ラー 9の表面には現像剤によるフィ ルミ ングは認められ なかった。 Using an image forming apparatus including the developing device having the above-described configuration, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed, but the obtained image has a high resolution similar to the first print. A high quality image was obtained at a high port degree. In addition, filming with the developer was observed on the surface of the magnetic roller 9. Did not.
比較例 E 4  Comparative Example E 4
比較例 E 3と同様な構成の現像装置による画像形成装 置を用いて、 実施例 E 4と同様に画像を連続して形成し たところ、 得られた画像は画像濃度が低く、 さらに A 4 サイズ普通紙 3 0 0 0 0枚相当の画像を連梡して形成し たころから、 得られた画像は刷毛目等のかすれが認めら れる低 ®質の画像となった。 また、 磁性休ローラー 9の 表面には現像剤によるフィ ルミ ングが認められた。  An image was continuously formed in the same manner as in Example E4 by using an image forming apparatus with a developing device having the same configuration as that of Comparative Example E3. From the time when images corresponding to the size of 30000 sheets of plain paper were successively formed, the obtained images were low-quality images in which blurring such as brush lines was observed. In addition, filming by the developer was observed on the surface of the magnetic roller 9.
, 実施例 E 5 , Example E 5
本実施例においては、 磁性体ローラー 9と してプラセ ォジゥム ♦鉄系铸造磁石を用い、 被覆雇としてポリ ウレ タン樹脂により均一な （磁石の露出のない） 被覆層を形 成した。  In the present embodiment, a uniform coating layer (without exposure of the magnet) was formed with a polyurethane resin as a coating layer by using a plastic ♦ iron-based magnet as the magnetic roller 9.
前記構成の現像装置による画像形成装置を用いて、 A 4サイズ普通紙 5 0 0 0枚相当め画像を連続して形成 したが、 得られた画像は印字 1枚目と同様に高解像度か つ高濃度で高品質な画像が得られた。  Using an image forming apparatus including the developing device having the above-described configuration, an image corresponding to 500 sheets of A4 size plain paper was continuously formed, but the obtained image had a high resolution and the same as the first print. A high-density and high-quality image was obtained.
比較例 E 5  Comparative Example E 5
磁性体ローラー 9の表面に被覆層がないこと以外は実 施例 E 5と同様な構成の現像装置による画像形成装置を 用いて、 同様の条件下に於て画像を連続して形成したと ころ、 得られた画像は画像濃度が低くかつ濃度ムラが認 められる低画質の画像であった。 実施例 E 6 An image was continuously formed under the same conditions using an image forming apparatus using a developing device having the same configuration as that of Example E5 except that there was no coating layer on the surface of the magnetic roller 9. The obtained image was a low-quality image with low image density and uneven density. Example E 6
本実施例においては、 磁性体ローラー 9としてネオジ ゥム ·鉄系焼結磁石を用い、 被覆雇として四フ ッ化工チ レン樹脂粒子を分散したポリウ レタン樹脂により均一な (磁石の露出のない） 被覆餍を形成した。  In this embodiment, a neodymium-iron sintered magnet is used as the magnetic roller 9, and the coating is made uniform (no magnet is exposed) by a polyurethane resin in which tetrafluorocarbon titanium resin particles are dispersed. A coating 餍 was formed.
前記構成の現像装置による画像形成装置を用いて、 A 4サイズ普通紙 5 0 0 0 0枚相当の画像を速铙して形成 したが、'得られた画像は印字 1枚目と同様に髙解像度か つ高濃度で高品質な画像が得られた。 また、 磁性体ロー ,ラー 9の表面には現像剤によるフイルミ ングは認められ なかった。  An image equivalent to 500 sheets of A4 size plain paper was formed at an accelerated rate using an image forming apparatus with the developing device having the above-described configuration. High-quality images with high resolution and high density were obtained. Also, no filming by the developer was observed on the surface of the magnetic material row 9.
比較例 E 6  Comparative Example E 6
比較例 E 5と同様な構成の現像装置による画像形成装 置を用いて、 実施例 E 6と同様に画像を連铳して形成し たところ、 得られた画像は画像濃度が低く、 さらに A 4 サイズ普通紙 3 0 0 0 0枚相当の画像を連続して形成し たころから、 得られた画像は刷毛目等のかすれが認めら れる低画質の画像となった。 また、 磁性体ローラー 9の 表面には現像剤によるフイ ルミ ングが認められた。  When an image was continuously formed in the same manner as in Example E6 using an image forming apparatus with a developing device having the same configuration as that of Comparative Example E5, the obtained image had a low image density, and furthermore A Since an image equivalent to three-hundred and four sheets of plain paper of four sizes was continuously formed, the obtained image was a low-quality image in which blurring such as brush lines was observed. Further, filming by the developer was observed on the surface of the magnetic roller 9.
導電性材料層の形成  Formation of conductive material layer
本発明の現像装置においては、 前記磁性体ローラーの 磁石材料としては、 フェライ ト、 アルニコ、 マンガンァ ルミ、 希土類磁石等の公知の磁石材料を使用することが できる。 しかしながら、 フユライ ト磁石等の高抵抗材料 を前記磁性体ローラーと して用いる場合には、 現像時に 前記磁性体ローラー上を搬送される現像剤に現像バイァ ス電圧を印加したり、 潜像担持体上の静電潜像を構成す る電位ボンテンシャルにより形成される電界を強調する ため等のいわゆる現像镭極を別途設置するかあるいは前 記磁性体ローラーの内部に設置されるヨークあるいはシ ャフ ト等の導電性部材を現像電極と して用いることにな るために、 前者の場合には構造が複雑になるという問題 力、'、 また後者の場合には現像電極が潜像担持体や現像剤 から離れた位置に設置されることによる解像度の低下や 実効的現像バイァスの低下を補うための電源の高出力化 に伴う消费エネルギーの増加などの問題が生じる。 また、 希土類磁石等の導電性材料を前記磁性体ローラ一として 用いる場合においては磁性体部分を現像電極と して用い ることが可能ではあるが、 前記磁性体ローラー表面の酸 化腐食が生ずるために高品質な画像を長期間安定して形 成することができないという問題があるために、 実際に 希土類磁石による磁性体ローラー使用する場合には前記 磁性体ローラー表面の酸化腐食を防止するために表面に 表面腐食防止層を設ける必要があり、 前記表面腐食防止 層として樹脂等の高抵抗材料により前記磁性体ローラー を被覆した場合には、 やはりフユライ ト磁石等の高抵抗 材料を前記磁性体ローラーとして用いる場合と同様に現 像電極が別途設置されなければならなく なることによる 構造の複雑化やあるいは現像電極が潜像担持体や現像剤 から離れた位置に設置されることによる解像度の低下や 消費エネルギーの增加などの問題を生じる場合がある。 本発明においては、 磁性体ローラーの表面に、 少なく とも 1種類の導電性材料からなる被 S層を設けることに より、 上記の問題点を防止することができる。 すなわち、 導電性材料層が現像電極として機能することにより、 高 品質な画像を長期間安定的に形成することが可能となる。 現像装置 7は現像剤の構成要素である現像剤 8を带電 させ、 かつ現像剤 8を回転する円筒状の磁性体ローラー 9で搬送するものである。 磁性体ローラー 9上に磁気力 により保持された現像剤 8は現像剤搬送量規制部材 1 0 により適量に規制された後に潜像担持体 1と磁性体ロー ラー 9が近接する現像ギャ ップ部に搬送される。 この場 合においては、 磁性体口一ラー 9の表面は、 少なく とも 1種類の導電性材料からなる被覆瘙 （図示せず） によつ て被覆されており、 特にフェライ ト磁石等の高抵抗材料 を用いるあるいは表面腐食防止層を設けた希土類磁石等 を前記磁性体ローラーとして用いる場合には現像電極と して被覆層が機能することにより、 現像バイアス電圧印 加手段 1 0によりバイァス電圧が現像剤 8に印加され、 潜像担持体 1上の静電潜像の電位ポテンシャルに応じて 現像剤 8が潜像担持体 1の静電潜像に付着することによ つて潜像担持体 1上の静電潜像が顕像化される。 潜像担持体 1上の （静電潜像を現像した） 現像剤 8が 転写器 1 4により記録紙 1 5に転写され、 さらに加圧や 加熱等の手段により記録紙 1 5に定着されることによつ て所望の画像を得ることができる。 In the developing device of the present invention, a known magnet material such as ferrite, alnico, manganese aluminum, and rare earth magnet can be used as the magnet material of the magnetic roller. However, high-resistance materials such as When the developer is used as the magnetic roller, a developing bias voltage is applied to the developer conveyed on the magnetic roller during development, or an electrostatic latent image on the latent image carrier is formed. A so-called developing electrode for enhancing the electric field formed by the potential bond is separately installed, or a conductive member such as a yoke or a shaft installed inside the magnetic roller is used as a developing electrode. In the former case, the structure becomes complicated, and in the latter case, the developing electrode is installed at a position away from the latent image carrier and the developer. As a result, problems such as a decrease in resolution and an increase in power consumption due to an increase in output of a power supply to compensate for a decrease in effective development bias occur. When a conductive material such as a rare earth magnet is used for the magnetic roller, the magnetic part can be used as a developing electrode, but oxidation corrosion of the surface of the magnetic roller occurs. However, when a high quality image cannot be stably formed for a long period of time, when a magnetic roller using a rare earth magnet is actually used, it is necessary to prevent oxidative corrosion of the surface of the magnetic roller. When it is necessary to provide a surface corrosion prevention layer on the surface, and when the magnetic roller is coated with a high resistance material such as a resin as the surface corrosion prevention layer, a high resistance material such as a fluoride magnet is also applied to the magnetic roller. As the imaging electrode must be installed separately In some cases, the structure may be complicated, or the developing electrode may be located away from the latent image carrier or the developer, causing problems such as a reduction in resolution and an increase in energy consumption. In the present invention, the above-mentioned problems can be prevented by providing an S layer made of at least one kind of conductive material on the surface of the magnetic roller. That is, since the conductive material layer functions as a developing electrode, a high-quality image can be stably formed for a long period of time. The developing device 7 discharges the developer 8 as a component of the developer, and transports the developer 8 by a rotating cylindrical magnetic roller 9. The developer 8 held by the magnetic force on the magnetic roller 9 is regulated to an appropriate amount by the developer conveying amount regulating member 10 and then the developing gap portion where the latent image carrier 1 and the magnetic roller 9 come close to each other. Transported to In this case, the surface of the magnetic material nozzle 9 is covered with a coating (not shown) made of at least one kind of conductive material, and in particular, a high resistance material such as a ferrite magnet. When a material or a rare earth magnet or the like provided with a surface corrosion prevention layer is used as the magnetic roller, the bias voltage is developed by the developing bias voltage applying means 10 because the coating layer functions as a developing electrode. Is applied to the developer 8, and the developer 8 adheres to the electrostatic latent image on the latent image carrier 1 according to the potential of the electrostatic latent image on the latent image carrier 1, thereby causing the developer 8 to adhere to the latent image carrier 1. Are visualized. The developer 8 (on which the electrostatic latent image has been developed) on the latent image carrier 1 is transferred to the recording paper 15 by the transfer device 14 and is then fixed to the recording paper 15 by means such as pressure or heating. Thus, a desired image can be obtained.
第 1図においてはバイアス印加手段 1 0の一方 （潜像 担持体 1を構成する支持体に電気的に接続しなかった側） を被 S雇に電気的に接続するものとして示したが、 これ は本発 を限定するものではなく、 明らかなようにバイ ァス印加手段 1 0の一方は磁性体ローラー 9を構成する ,磁石 1 2あるいは磁石 1 2と電気的に接続されるヨーク 1 3等の導電性支持体、 あるいは被覆層の少なく とも 1 箇所に電気的に接統されていればよい。 バイアス印加手 段 1 0の一方が磁性体口一ラー 9を構成する磁石 1 2あ るいは磁石 1 2と電気的に接銃されるヨーク 1 3等の導 電性支持体、 あるいは被覆層の少なく とも 1箇所に電気 的に接続されていれば、 本発明における被覆雇により、 潜像担持体 1上の静電潜像を構成する電位ポテンシャル による電界が強調されるなどの現像電極効果が認められ るが、 充分な現像電極効果を得るためには、 また、 現像 バイアスに対する印加手段 1 0の出力効率化という観点 からは、 磁性体ローラー 9と して用いる磁石として特に フユライ ト等の高抵抗材料を用いる場合あるいは極めて 厚いかつ高抵抗な表面腐食防止層を有する希土類磁石を 用いる場合には、 被覆層に印加手段 1 0が接続され、 被 覆層が現像電極として機能することが望ましい。 尚、 表 面腐食防止層としても充分な効果を発揮するように本発 明における被覆雇を設けたあるいは極めて薄い表面腐食 餍上に被覆層を設けた導電性材料である希土類磁石等を 用いた磁性体ローラー 9の場合は磁性体ローラー 9を構 成する磁石 1 2あるいは磁石 1 2とヨーク 1 3等の導電 性支持体、 あるいは被覆層の少なく とも 1箇所に接铙さ れていれば充分な現像電極効^が得られる。 In FIG. 1, one of the bias applying means 10 (the side not electrically connected to the support constituting the latent image carrier 1) is shown as electrically connected to the employee. Does not limit the present invention, as is apparent, one of the bias applying means 10 constitutes the magnetic roller 9, the magnet 12 or the yoke 13 electrically connected to the magnet 12, etc. It is only necessary that at least one conductive support or the coating layer be electrically connected. One of the bias applying means 10 is a conductive support such as a yoke 13 electrically connected to the magnet 12 or the magnet 12 or the magnet 12 constituting the magnetic material aperture 9 or the coating layer. As long as it is electrically connected to at least one location, the coating electrode according to the present invention recognizes a developing electrode effect such as an enhancement of an electric field due to a potential potential constituting an electrostatic latent image on the latent image carrier 1. However, in order to obtain a sufficient developing electrode effect, and from the viewpoint of increasing the output efficiency of the application means 10 for the developing bias, the magnet used as the magnetic roller 9 is preferably made of a high resistance material such as a filament. When a material is used or when a rare earth magnet having an extremely thick and high resistance surface corrosion prevention layer is used, the applying means 10 is connected to the coating layer, and It is desirable that the cover layer functions as a developing electrode. In addition, a rare earth magnet or the like, which is a conductive material provided with a coating layer according to the present invention or provided with a coating layer on extremely thin surface corrosion, was used so as to exert a sufficient effect as a surface corrosion prevention layer. In the case of the magnetic roller 9, it is sufficient that the magnetic roller 9 is in contact with at least one of the magnets 12 or the conductive support such as the magnet 12 and the yoke 13 or the coating layer. A good developing electrode effect can be obtained.
実施例 F 1  Example F 1
· 本実施例においては、 磁性体ローラー 9としてフェラ ィ ト系焼結磁石を用い、 被覆層として、 N iを用いた ( N i によるメ ツキ被覆を行った） 。 In the present embodiment, a ferrite sintered magnet was used as the magnetic roller 9 and Ni was used as the coating layer (the coating was performed by Ni).
前記構成の現像装置による画像形成装置を用いて、 A 4サイズ普通紙 1 0 0 0枚相当の画像を連銃して形成 したが、 得られた画像は印字 1枚目と同様に解像度の高 い高品質な画像が得られた。  Using an image forming apparatus with the developing device having the above-described configuration, images equivalent to 100 sheets of A4 size plain paper were formed by successive guns, and the obtained images had high resolution similarly to the first print. A high quality image was obtained.
実施例 F 2  Example F 2
本実施例においては、 被覆雇として A 1微粒子をェポ キシ樹脂中に分散したものを用いた以外は実施例 F 1 と 同様の構成とした。  In this example, the same configuration as in Example F1 was used except that A1 fine particles dispersed in an epoxy resin were used as the coating.
前記構成の現像装置による画像形成装置を用いて、 A 4サイズ普通紙 1 0 0 ◦枚相当の画像を連続して形成 したが、 得られた画像は印字 1枚目と同様に解像度の高 い高品質な画像が得られた。 . 比較例 F l Using an image forming apparatus having the above-described developing device, an image equivalent to 100 A4 size plain paper was continuously formed, but the obtained image had a high resolution similarly to the first print. High quality images were obtained. . Comparative example F l
磁性体ローラー 9の表面に被覆層を設けずに磁石が露 出している以外は実施例 F 1及び F 2と同様な構成の現 像装 Sによる画像形成装置を用いて、 同様の条件下に於 て画像を連続して形成したところ、 得られた画像は印字 1枚目から画像がかすれており目視による判読が不可能 であった。  Under the same conditions, using the image forming apparatus with the image forming apparatus S having the same configuration as that of the embodiments F1 and F2 except that the magnet is exposed without providing the coating layer on the surface of the magnetic roller 9. When images were continuously formed, the obtained images were blurred from the first printed sheet and could not be visually read.
実施例 F 3  Example F 3
本実施例においては、 磁性体ローラー 9と してサマリ ,ゥ厶コバルト系射出成形磁石を用い、 被 ¾屦と して A 1 を用いた （A 1 によるメ ツキ被覆を行った） 以外は実施 例 F 1 と同様の構成とした。  In the present embodiment, the procedure was performed except that the magnetic roller 9 was a summary, a cobalt-based injection-molded magnet, and A 1 was used as the coating (the plating was performed with A 1). The configuration was the same as in Example F1.
前記構成の現像装置による画像形成装匿を用いて、 A 4サイズ普通紙 1 0 0 0枚相当の画像を連铳して形成 したが、 得られた画像は印字 1枚目と同様に解像度の高 い高品質な画像が得られた。  Using the image forming and concealment by the developing device having the above configuration, images equivalent to 100 sheets of A4 size plain paper were continuously formed, but the obtained image had the same resolution as the first sheet of printing. High quality images were obtained.
比較例 F 2  Comparative Example F 2
磁性体ローラー 9の表面に被覆層を設けずに磁石が露 出している以外は実施例 F 3と同様な構成の現像装置に よる画像形成装置を用いて、 同様の条件下に於て画像を 連続して形成したところ、 得られた画像は印字 1枚目か ら画像がかすれており目視による判読が不可能であつた 実施例 F 4  An image was formed under the same conditions using an image forming apparatus using a developing device having the same configuration as in Example F3 except that the magnet was exposed without providing a coating layer on the surface of the magnetic roller 9. When images were formed continuously, the obtained images were blurred from the first printed sheet and could not be visually read. Example F 4
本実施例においては、 磁性体ローラー 9と してサマリ ゥムコバルト系押出成形磁石を用いた以外は実施例 F 3 と同様の構成とした。 In this embodiment, the magnetic material roller 9 is used as a summary. The configuration was the same as that of Example F 3 except that a palladium-based extruded magnet was used.
前記構成の現像装置による画像形成装置を用いて、 A 4サイズ普通紙 1 0 0 0枚相当の画像を連铙して形成 したが、 得られた画像は印字 1枚目と同様に解像度の高 ぃ髙品質な画像が得られた。  Using an image forming apparatus with the developing device having the above-described configuration, images equivalent to 100 sheets of A4 size plain paper were continuously formed, but the obtained images had high resolution similarly to the first print.ぃ 髙 High quality images were obtained.
実施例 F 5  Example F 5
本実施例においては、 被覆雇としてカーボンブラック をポリエステル樹脂中に分散したものを用いた以外は実 ,施例 F 4と同様の構成とした。  In this example, the configuration was actually the same as that of Example F4, except that carbon black dispersed in a polyester resin was used as the coating.
前記構成の現像装置による画像形成装置を用いて、 A 4サイズ普通紙 1 0 0 0枚相当の画像を連続して形成 したが、 得られた画像は印字 1枚目と同様に解像度の高 い高品質な画像が得られた。  An image corresponding to 100 A4 size plain paper was continuously formed using an image forming apparatus including the developing device having the above-described configuration, but the obtained image had high resolution similarly to the first print. High quality images were obtained.
比較例 F 3  Comparative Example F 3
磁性体ローラ一 9の表面に被覆層を設けずに磁石が露 出している以外は実施例 F 4及び F 5と同様な構成の現 像装置による画像形成装置を用いて、 同様の条件下に於 て画像を連続して形成したところ、 得られた画像は印字 1枚目から画像がかすれており目視による判読が不可能 あつ o  Using an image forming apparatus having a configuration similar to that of Examples F4 and F5, except that the magnet was exposed without providing the coating layer on the surface of the magnetic roller 19, under the same conditions. When images were formed continuously at the same time, the obtained images were blurred from the first printed sheet and could not be visually read.
実施例 F 6  Example F 6
本実施例においては、 磁性体ローラー 9としてネオジ ゥム ♦鉄系焼結磁石を用い、 被覆層として A 1 を用いた ( A 1 によるメ ツキ被覆を行った） 以外は実施例 F 1 と 同様の構成と した。 In this example, neodymium iron-based sintered magnet was used as the magnetic roller 9 and A 1 was used as the coating layer. The configuration was the same as that of Example F1 except that the plating was performed by A1.
前記構成の現像装匿による画像形成装匿を用いて、 温 度 2 0 °C、 相対湿度 6 0 %の ¾5境下に於て A 4サイズ普 通紙 5 0 0 0 0枚相当の画像を連続して形成したが、 得 られた画像の劣化は認められず、 印字 1枚目と同様に解 像度の高い高品質な画像が得られた。 また、 磁性体ロー ラー 9の表面の酸化腐食は認められなかつた。  Using the image forming and concealment by the development and concealment of the above-described configuration, an image equivalent to 500 000 sheets of A4 size ordinary paper is obtained at a temperature of 20 ° C. and a relative humidity of 60% under ¾5. Although it was formed continuously, no deterioration of the obtained image was observed, and a high-quality image with high resolution was obtained as in the case of the first printed sheet. Further, no oxidative corrosion of the surface of the magnetic roller 9 was observed.
実施例 F 7  Example F 7
, 本実施例においては、 被笾層としてカーボンブラ ック をポリカーボネー ト樹脂中に分散したものを用いた以外 は実施例 F 6と同様の構成とした。 However, in this example, the same configuration as in Example F6 was used, except that a layer in which carbon black was dispersed in a polycarbonate resin was used as the coating layer.
前記構成の現像装置による画像形成装置を用いて、 実 施例 6同様の環境下において A 4サイズ普通紙  Using an image forming apparatus with the developing device having the above-described configuration, A4 size plain paper was obtained under the same environment as in Example 6.
5 0 0 0 0枚相当の画像を連続して形成したが、 得られ た画像の劣化は認められず、 印字 1'枚目と同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面の酸化腐食は認められなかつた。  Although an image corresponding to 5,000 sheets was continuously formed, no deterioration of the obtained image was observed, and a high-quality image with high resolution was obtained as in the case of the 1'th printed sheet. Also, no oxidative corrosion of the surface of the magnetic roller 9 was observed.
比較例 F 4  Comparative Example F 4
磁性体ローラ一 9の表面に被覆層を設けずに磁石が露 出している以外は実施例 F 6及び F 7と同様な構成の現 像装置による画像形成装置を用いて、 実施例 F 6と同様 の環境下において A 4サイズ普通紙 5 0 0 0 0枚相当の 画像を連続して形成したところ、 得られた画像には刷毛 目等のかすれや地被り等の劣化が認められ、 また、 磁性 体ローラー 9の表面には酸化腐食が認められた。 Example F6 was performed using an image forming apparatus having a configuration similar to that of Examples F6 and F7 except that the magnet was exposed without providing a coating layer on the surface of the magnetic roller 19. Under the same environment, an image equivalent to 500,000 sheets of A4 size plain paper was continuously formed. Deterioration such as blurring of the eyes and ground covering was observed, and oxidative corrosion was observed on the surface of the magnetic roller 9.
実施例 F 8  Example F 8
本実施例においては、 磁性体ローラー 9としてブラセ ォジゥム ·鉄系^造磁石を用い、 被覆層として N i を用 いた （N i によるメ ツキ被覆を行った） 以外は突施例 F 1 と同様の構成とした。  In the present example, the same as in Example F1 except that a brassiodium / iron-based magnet was used as the magnetic roller 9 and Ni was used as the coating layer (the plating was performed with Ni). Configuration.
前記 成の現像装匿による画像形成装 Sを用いて、 実 施例 F 6同様の環境下に於て A 4サイズ普通紙  A4 size plain paper under the same environment as in Example F6 using the image forming apparatus S with the developing
, 5 0 0 0 0枚相当の画像を連铳して形成したが、 得られ た画像の劣化は認められず、 印字 1枚目と同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面には酸化腐食は認められなかった。 However, no deterioration of the obtained image was observed, and a high-quality high-resolution image was obtained as in the case of the first print. No oxidative corrosion was observed on the surface of the magnetic roller 9.
実施例 F 9  Example F 9
本実施例においては、 被覆層として A 1微粒子をフッ 素樹脂中に分散したものを用いた以外は実施例 F 8と同 様の構成とした。  In this example, the same configuration as that of Example F8 was used except that a coating layer in which A1 fine particles were dispersed in a fluorine resin was used.
前記構成の現像装置による画像形成装置を用いて、 実 施例 F 6同様の環境下に於て A 4サイズ普通紙  Using an image forming apparatus with the developing device having the above-described configuration, A4 size plain paper under the same environment as in Example F6.
5 0 0 0 0枚相当の画像を連続して形成したが、 得られ た画像の劣化は認められず、 印字 1枚 Sと同様に解像度 の高い高品質な画像が得られた。 また、 磁性体ローラー 9の表面には酸化腐食が認められなかった。 比較例 F 5 Although an image corresponding to 500,000 sheets was continuously formed, no deterioration of the obtained image was observed, and a high-quality image with high resolution was obtained as in the case of single print S. No oxidative corrosion was observed on the surface of the magnetic roller 9. Comparative Example F 5
磁性体ローラー 9の表面に被覆層を設けずに磁石が露 出している以外は実施例 F 8及び F 9と同様な構成の現 像装置による画像形成装置を用いて、 実施例 F 6と同様 の環境下において A 4サイズ普 ¾紙 5 0 0 0 0枚相当の 画像を迪銃して形成したところ、 得られた画像には刷毛 目等のかすれや地被り等の劣化が認められ、 また、 磁性 体ローラー 9の表面には酸化腐食が認められた。  Same as Example F6, except that the magnet was exposed without providing a coating layer on the surface of the magnetic material roller 9 except that the magnet was exposed. Under the environment of the above, an image equivalent to 50,000 sheets of A4 size plain paper was formed by using a gun, and the obtained image showed blurring such as brush eyes and deterioration of ground covering. However, oxidation corrosion was observed on the surface of the magnetic roller 9.
以上述べたように、 本実施態様によれば、 複数の磁極 , に着磁された円筒状の磁性体ローラーを有し、 前記磁性 体ローラーにより発生する磁場により現像剤を前記磁性 体ローラー上に保持し、 前記磁性体ローラーを回転させ て前記現像剤を搬送する現像装匿において、 前記磁性体 ローラ一の表面 （現像剤搬送面） に少なく とも 1種類の 導電性材料からなる被覆雇を設けることにより、 前記導 電性材料が現像電極として機能することにより、 高品質 な画像を長期間安定して形成できる、 という効果を奏す る。  As described above, according to the present embodiment, the magnetic roller has a cylindrical magnetic roller that is magnetized to a plurality of magnetic poles, and the developer is placed on the magnetic roller by a magnetic field generated by the magnetic roller. In developing and holding the developer while transporting the developer by rotating the magnetic roller, a cover made of at least one kind of conductive material is provided on the surface (developer transport surface) of the magnetic roller. Thereby, the conductive material functions as a developing electrode, thereby producing a high-quality image stably for a long period of time.
現像剤搬送量規制部材の改良  Improvement of developer conveyance amount regulating member
上記のような本発明の現像装置においては、 現像剤の 搬送量を磁性体ローラーの磁極ピッチのみを調整するこ と、 あるいは第 1図に示す現像剤搬送量規制部材 1 0の ような形態によっては、 均一な トナー薄層を安定的に形 成することは必ずしも容易ではない。 本実施態様においては、 磁性体ローラーの表面と、 現 像剤搬送量規制部材とが面接触し、 かつ、 この現像剤搬 送量規制部材の端部が磁性体ローラーに非接触となるよ うな現像剤搬送量規制部材を具備することによって、 上 記の問題を解決することができる。 In the developing device of the present invention as described above, the amount of the developer transported is adjusted by adjusting only the magnetic pole pitch of the magnetic roller, or by a form such as the developer transport amount regulating member 10 shown in FIG. However, it is not always easy to stably form a uniform thin toner layer. In the present embodiment, the surface of the magnetic roller is in surface contact with the developing agent transport amount regulating member, and the end of the developer transport amount regulating member is not in contact with the magnetic roller. The provision of the developer conveyance amount regulating member can solve the above problem.
上記の構成によれば、 磁性体ローラーと現像剤搬送量 規制部材との間を現像剤が通過する際に、 磁性体ローラ 一上の ¾像剤に加えられる圧力が増加するために磁性体 ローラーにより搬送される現像剤は薄層化され、 さらに 磁性体ローラーと弾性体である現像剤搬送量規制部材を 面接触させることにより接触面には均一な応力が加えら れるために均一な現像剤屨を安定的に形成でき、 これに より高品質な画像を安定して形成することが可能となる。 第 4図に本発明の実施例における現像装置を含む画像 形成装置の断面概観図を示す。  According to the above configuration, when the developer passes between the magnetic roller and the developer conveyance amount regulating member, the pressure applied to the image agent on the magnetic roller increases, so that the magnetic roller The developer conveyed is thinned, and a uniform stress is applied to the contact surface by bringing the magnetic roller into contact with the elastic developer transfer amount regulating member, so that uniform developer is applied.屨 can be formed stably, and thereby, a high-quality image can be stably formed. FIG. 4 is a schematic cross-sectional view of an image forming apparatus including a developing device according to the embodiment of the present invention.
図中 Aに示す方向に回転する潜像担持体 1は導電性の 支持体 2の上に光導電性を有する感光層 3を塗膜したも のであって、 感光層 3を帯電器 4により所定の電位にな るように帯電させた後に画像に応じて光源 5から出射し た光を結像光学系 6により感光層 3に結像させて電位コ ン トラス トを得て潜像担持体 1上に静電潜像を形成する, 現像装置 7は現像剤の構成要素である現像剤 8を帯電 させ、 かつ現像剤 8を図中 Bに示す方向に回転する円筒 状の磁性体ローラー 9で搬送するものである。 磁性体口 一ラー 9上に磁気力により保持された現像剤 8は現像剤 搬送量規制部材 1 1により適量に規制された後に潜像担 持体 1 と磁性体ローラー 9が近接する現像ギヤ ッブ部に 搬送され、 潜像担持体 1上の静¾潜像の ¾位ポテンシャ ル及び現像バイアス電圧印加手段である電源 1 0による バイアス電圧に応じて現像剤 8が潜像担持体 1の静電潜 像に付着することによつて潜像担持体 1上の静電潜像が 顕像化される。 The latent image carrier 1 rotating in the direction indicated by A in the figure is a photoconductive layer 3 coated on a conductive support 2, and the photosensitive layer 3 is charged by a charger 4. After being charged to a potential of the latent image carrier 1, the light emitted from the light source 5 is imaged on the photosensitive layer 3 by the imaging optical system 6 in accordance with the image to obtain a potential contrast. Forming an electrostatic latent image thereon, a developing device 7 charges a developer 8 which is a component of the developer, and a cylindrical magnetic roller 9 which rotates the developer 8 in a direction indicated by B in the figure. To be transported. Magnetic mouth The developer 8 held by the magnetic force on the roller 9 is regulated to an appropriate amount by the developer carrying amount regulating member 11, and then is moved to the developing gear portion where the latent image carrier 1 and the magnetic material roller 9 are close to each other. The developer 8 is conveyed, and the developer 8 is charged with an electrostatic latent image on the latent image carrier 1 in accordance with the potential of the static latent image on the latent image carrier 1 and the bias voltage from the power supply 10 which is a developing bias voltage applying unit. The electrostatic latent image on the latent image carrier 1 is visualized by adhering to the surface.
こ こで、 現像剤搬送量規制部材 1 1 は例えばリ ン青銅 ，あるいはステンレスなどの弾性を有する金属あるいはポ リ ウ レタ ンゴムなどのエラス トマ一により形成され、 現 像剤搬送量規制部材 1 1 の自由端、 すなわち現像像 8の 流れからみて下流側に位置するェッジが磁性体ローラ一 9に接触せず、 その自由端を除く面が圧接かつ面接触し ている。 このような構成によれば、 磁性体ローラー 9を 図中 Aの方向に回転させると、 磁^体ローラー 9の回転 に従い現像剤 8は磁性体ローラー 9に沿って現像剤搬送 量規制部材 1 1の圧接力下へ搬送される。 現像剤搬送量 規制部材 1 1は磁性体ローラー 9に対して現像剤搬送量 規制部材 1 1 の自由端が磁性体口一ラー 9に非接触とな 'るように面接触しているため、 現像剤搬送量規制部材 1 1による磁性体ローラー 9への圧接力が均一化され、 非常に高い圧接力下においても、 言い換えれば幅広い範 囲の圧接力下においても、 さ らには塑性変形し易いある いは自己凝集性の強い現像剤を用いる場合に於いても均 —な厚さの現像剤薄雇を安定して形成できる。 Here, the developer transporting amount regulating member 11 is formed of an elastomer such as phosphor bronze, an elastic metal such as stainless steel, or polyurethane rubber, and the developing agent transporting amount regulating member 11 is used. The free end, ie, the edge located downstream from the flow of the developed image 8 does not contact the magnetic roller 19, and the surface except the free end is in pressure contact and surface contact. According to such a configuration, when the magnetic roller 9 is rotated in the direction of A in the figure, the developer 8 follows the rotation of the magnetic roller 9 and the developer 8 moves along the magnetic roller 9 to regulate the amount of the developer transported. Conveyed under the pressing force of Since the developer conveying amount regulating member 11 is in surface contact with the magnetic roller 9 such that the free end of the developer conveying amount regulating member 11 is not in contact with the magnetic opening 9, The pressure applied to the magnetic roller 9 by the developer conveyance amount regulating member 11 is made uniform, and plastic deformation occurs even under extremely high pressure, in other words, under a wide range of pressure. Easy Alternatively, even when a developer having strong self-cohesiveness is used, it is possible to stably form a thinner developer with a uniform thickness.
潜像担持体 1上の （静電潜像を現像した） 現像剤 8が 転写器 1 4により記録紙 1 5に転写され、 さらに加圧や 加熱等の手段により記録紙 1 5に定着されることによつ て所望の画像を得ることができる。  The developer 8 (on which the electrostatic latent image has been developed) on the latent image carrier 1 is transferred to the recording paper 15 by the transfer device 14 and is then fixed to the recording paper 15 by means such as pressure or heating. Thus, a desired image can be obtained.
尚、 本実施例においては、 第 4図に示すように潜像担 持体 1及び磁性体ローラー 9の回転方向をそれぞれ図中 A及び Bとして示したが、 これは本発明を限定するもの ，ではない。 また、 本発明においては、 1成分磁気ブラシ 現像剤及び 2成分磁気ブラシ現像剤として公知の現像剤 ならばすベて使用可能である。  In this embodiment, as shown in FIG. 4, the rotation directions of the latent image carrier 1 and the magnetic roller 9 are shown as A and B in the figure, respectively. is not. Further, in the present invention, any known developer as a one-component magnetic brush developer and a two-component magnetic brush developer can be used.
回転方向の制御  Control of rotation direction
本発明の現像剤装置においては、 磁性体ローラーの回 転方向と潜像担持体の回転方向とを逆方向に設定し、 か つ、 磁性体ローラーの周速度が、 潜像担持体の周速度よ り も速く なるように設定することによって、 画像品質を —層良好なものにすることができる。  In the developer device of the present invention, the rotation direction of the magnetic roller and the rotation direction of the latent image carrier are set in opposite directions, and the peripheral speed of the magnetic roller is set to the peripheral speed of the latent image carrier. By setting it to be faster, the image quality can be better.
すなわち、 上記のように回転方向と回転速度の双方を 制御することによって、 磁性体ローラーによる現像阻止 力を十分に大きく して背景部 （地の部分） への現像剤の 付着を低減させることができる。 さらに、 磁性体ローラ 一の回転方向を潜像担持体と反対方向に回転させて、 か つ、 磁性体ローラーの周速度を潜像担持体？周速度より も速くすると、 印字部の後端で磁気ブラシが現像剤を過 剰供給するのを防止でき、 これにより後端エッ ジ部への 不要な現像剤の蓄積をなく し画像品質を向上することが できる。 In other words, by controlling both the rotation direction and the rotation speed as described above, it is possible to sufficiently increase the development inhibiting force of the magnetic roller to reduce the adhesion of the developer to the background portion (ground portion). it can. Further, the rotation direction of the magnetic roller is rotated in the opposite direction to the latent image carrier, and the circumferential speed of the magnetic roller is changed to the latent image carrier. From peripheral speed A faster speed can prevent the magnetic brush from over-supplying the developer at the trailing edge of the printing area, thereby eliminating unnecessary accumulation of developer on the trailing edge and improving image quality. it can.
第 1図に示すように、 磁性体ローラー 9の回転方向 (反時計方向） は潜像担持体 1 の回転方向 （時計方向） と反対で現像ギヤ ップ部では両者が順方向に移勅してお り、 印学部後端へ現像剤 8が過剰に供給され蓥稹するこ とを防止して尾引きを低減し、 これにより解像度は向上 ，する。 尚、 矢印はそれぞれの部材の回転方向を示すもの C 'める。  As shown in Fig. 1, the rotation direction (counterclockwise) of the magnetic roller 9 is opposite to the rotation direction (clockwise) of the latent image carrier 1, and both are transferred in the forward direction in the developing gap. In this way, it is possible to prevent the developer 8 from being supplied excessively to the rear end of the printing school, thereby reducing tailing, thereby improving the resolution. The arrow indicates the rotation direction of each member.
実施例 G 1  Example G 1
第 1図に示されるような現像装置で、 外径 2 0 na肉厚 1 maで 6 0極に分割 ¾磁したフユライ ト磁石とその内部 に磁気回路を構成する外径 1 8 M肉厚 I IDBのヨークとで 磁性体ローラーを構成し、 磁性体 —ラーを 2 0 O rpm で反時計方向に回転させ、 一方外径 3 0 ΒΠ8の潜像担持体 を 3 O rpro で磁性体ローラーと反対方向 （時計方向） に 回転させて画像形成を行ったところ、 印字部後端の尾引 きがなく なり高濃度で濃度むらがなく コン トラス トの高 い画像を安定して形成することができた。 また、 従来の フヱライ ト磁石と金属ス リーブを fflいたものに比べ半分 以下に軽量化することができた。 実施例 G 2 A developing device as shown in Fig. 1, divided into 60 poles with an outer diameter of 20 na and a wall thickness of 1 ma ¾ A magnet with a magnet and an outer diameter of 18 M that forms a magnetic circuit inside I A magnetic roller is composed of the yoke of IDB and the magnetic roller is rotated counterclockwise at 20 O rpm, while the latent image carrier having an outer diameter of 30ΒΠ8 is opposed to the magnetic roller by 3 Orpro. When the image is formed by rotating it in the clockwise direction (clockwise), the trailing edge of the printing section is no longer trailing, and a high-contrast image without high-density unevenness can be formed stably. Was. In addition, the weight was reduced to less than half that of the conventional ffl magnet and metal sleeve. Example G 2
第 1図に示されるような現像装置で、 外径 2 0 M肉厚 1 . 5 aaで 4 0極に分割着磁したサマリ ゥ厶コバル卜系 の圧縮成形磁石とその内部に磁気回路を構成する外径 1 7 M肉厚 1 maのヨークとで磁性体ローラーを構成し、 磁性体ローラーを 2 0 0 ΓΡΠ で反時計方向に回転させ、 —方外径 3 O weの潜像担持体を 3 0 rpi で磁性体ローラ 一と反対方向 （時計方向） に回転させて画像形成を行つ たところ、 印字部後端の尾引きがなく なり高濃度でコン , トラス トの高い画像を安定して形成することができた。 また、 従来のフェライ ト磁石と金属スリーブを用いたも のに比べ半分以下に軽量化することができた。  A developing device as shown in Fig. 1 is composed of a summary rubber-cobalt compression-molded magnet with an outer diameter of 20 M and a thickness of 1.5 aa and magnetized into 40 poles, and a magnetic circuit inside it. A magnetic roller is composed of an outer diameter of 17 M and a yoke with a thickness of 1 ma, and the magnetic roller is rotated counterclockwise at 200 ° to form a latent image carrier having an outer diameter of 3 O we. When the image was formed by rotating in the opposite direction (clockwise) to the magnetic roller at 30 rpi, the trailing edge of the printing section disappeared, and a high-density, high-contrast image with high density was stabilized. Could be formed. Also, the weight was reduced to less than half that of the conventional one using a ferrite magnet and a metal sleeve.
実施例 G 3  Example G 3
第 1図に示されるような現像装置で、 外径 1 2 M肉厚 1 amで 4 0極に分割着磁したサマリ ウムコバルト系の射 出成形磁石とその内部に磁気回路^構成する外径 1 O M 肉厚 1 Mのヨークとで一体に磁性体ローラーを構成し、 磁性体ローラーを 2 0 0 rpn で反時計方向に回転させ、 —方外径 2 0 MIの潜像担持体を 3 0 rpn で磁性体ローラ 一と反対方向 （時計方向） に回転させて画像形成を行つ たところ、 印字部後端の尾引きがなく なり高濃度でコン トラス トの高い画像を安定して形成することができた。 また、 磁性体ローラーは従来のフヱライ ト磁石と金属ス リーブを用いたものに比べ 4分の 1以下に輊量化するこ とができた。 A samarium-cobalt-based injection-molded magnet with an outer diameter of 12 M and a thickness of 1 am and magnetized into 40 poles with a developing device as shown in Fig. 1 and an outer diameter that constitutes a magnetic circuit inside A magnetic roller is integrally formed with the 1 OM yoke having a wall thickness of 1 M, and the magnetic roller is rotated counterclockwise at 200 rpn. When the image was formed by rotating the magnetic roller in the opposite direction (clockwise) with rpn, the trailing edge of the printed portion was lost, and a high-density, high-contrast image was formed stably. I was able to. In addition, the magnetic roller can be reduced to one-fourth or less the size of the conventional roller using a magnet and metal sleeve. I was able to.
比較例 G l  Comparative example G l
第 1図に示されるような現像装置で、 外径 2 0M肉厚 l mBで 6 0極に分割着磁したフ ライ ト磁石とその内部 に磁気回路を構成する外径 1 8 nnn肉厚 1 ID»のヨークとで 磁性体ローラーを構成し、 磁性体ローラーを 2 0 O rpm で反時計方向に回転させ、 一方外径 3 O innの潜像担持体 を 3 O rpin で磁性体ローラーと同一方向 （反時計方向） に回転させて画像形成を行ったところ、 印字部後端の現 ，像剤の滞留が発生し印字部後端に尾引きとなってコン ト ラス トの低い画像しか形成することができなかった。 In the developing apparatus shown in Figure 1, the outer diameter 1 8 nnn thickness 1 constituting the magnetic circuit off line bets magnet divided magnetizing 6 0 poles at the outer diameter 2 0M thickness lm B and therein A magnetic roller is composed with the yoke of ID », and the magnetic roller is rotated counterclockwise at 20 O rpm, while a latent image carrier having an outer diameter of 3 O inn is the same as the magnetic roller with 3 O rpin. When the image was formed by rotating it in the counterclockwise direction (counterclockwise), the image agent stayed at the trailing edge of the printing section, and the trailing edge of the printing section trailed, forming only an image with a low contrast. I couldn't.
比铰例 G 2  Comparative example G 2
従来の一成分磁性現像装置で、 外径 2 0 BBの現像剤搬 送部材 （非磁性の金属スリーブ） を用い、 その内部に配 設される磁性体ローラーを外径 1 8 肉厚 5 で8極に 分割着磁した焼結のフユライ ト磁右で構成し、 外径 3 0 maの潜像担持体を 3 O rpin で時計方向に回転させ、 現像 剤搬送部材を 2 0 O rpm で潜像担持体と同一方向 （時計 方向） に回転させ、 磁性体ローラーを 1 0 0 0 rpm で潜 像担持体と同一方向 （時計方向） に回転させて画像形成 を行ったところ、 印字部後端に尾引きを発生しコ ン トラ ス トの低い低解像度の画像しか形成することができなか つた。 また、 磁性体ローラーを軽量化することはできな 力、つた 0 比較例 G 3 A conventional one-component magnetic developing device that uses a developer carrying member (non-magnetic metal sleeve) with an outer diameter of 20 BB, and uses a magnetic roller placed inside it with an outer diameter of 18 and a wall thickness of 5 to 8 The latent image carrier with an outer diameter of 30 ma is rotated clockwise at 3 Orpin, and the developer transport member is rotated at 20 O rpm. The image was formed by rotating the magnetic roller in the same direction (clockwise) as the carrier and rotating the magnetic roller in the same direction (clockwise) as the latent image carrier at 1000 rpm. A trail was generated and only low-contrast, low-resolution images could be formed. In addition, force that cannot reduce the weight of the magnetic roller Comparative Example G 3
従来の一成分磁性現像装置で、 外径 2 0 maの現像剤搬 送部材 （非磁性の金属スリーブ） を用い、 その内部に配 設される磁性体ローラーを外径 1 8 ^1肉厚 5 10»で8極に 分割着磁した焼結のフユライ ト磁石で構成し、 外径 3 0 Mの潜像担持体を 3 0 ΓΡΠΙ で時計方向に回転させ、 現像 剤搬送部材を 2 0 O rpm で潜像担持体と反対方向 （反時 計方向）' に回転させ、 磁性体ローラーを 1 0 0 ◦ ΓΡΒ で 潜像担持体と同一方向 （時計方向） に回転させて画像形 ,成を行ったところ、 印字部後端に尾引きを発生しコン ト ラス 卜の低い低解像度の画像しか形成することができな かった。 また、 磁性体ローラーを軽量化することはでき "力、つた。 A conventional one-component magnetic developing device that uses a developer carrying member (non-magnetic metal sleeve) with an outer diameter of 20 ma and uses a magnetic roller placed inside it with an outer diameter of 18 ^ 1 thick 5 It is composed of sintered magnets divided into 10 poles and divided into 8 poles, and the latent image carrier having an outer diameter of 30 M is rotated clockwise at 30 °, and the developer transport member is rotated by 20 °. Rotate the magnetic roller in the direction opposite to the latent image carrier (counterclockwise) at rpm, and rotate the magnetic roller in the same direction (clockwise) as the latent image carrier at 100 ° As a result, tailing occurred at the rear end of the printed portion, and only low-resolution images with low contrast could be formed. Also, the weight of the magnetic roller can be reduced.
現像ギヤ ップの制御  Control of development gap
本発明の現像装置においては、 磁性体口—ラーの回転 方向と潜像担持体の回転方向とを崗一方向に設定し、 か つ、 現像ギヤ ップ部 （磁性体ローラーと潜像担持体とが 最も接近する部分） の間隙を、 磁性体ローラー上に保持 された現像剤の穂の高さの最小値より も大きく設定する ことによつても、 画像品質を一層良好なものにすること ができる。  In the developing device of the present invention, the rotation direction of the magnetic material roller and the rotation direction of the latent image carrier are set to one direction, and the developing gap portion (the magnetic material roller and the latent image carrier) is set. The image quality can be further improved by setting the gap between (the part closest to the surface) to be larger than the minimum height of the developer ears held on the magnetic roller. Can be.
すなわち、 上記のように回転方向と現像ギャ ップ部の 間隙を制御することによって、 磁性体ローラーによる現 像阻止力を十分に大きく して背景部 （地の部分） への現 像剤の付着を低減させることができる。 さらに、 現像ギ ャ ップ部において、 現像剤を潜像担持体に対して間欠接 触もしく は非接触状態になるようにし、 これにより不要 の現像剤の付着を低減させて画像品 Kを向上させること ができるのである。 In other words, by controlling the rotation direction and the gap between the developing gap as described above, the image blocking force of the magnetic roller is sufficiently increased, and the image is prevented from being applied to the background (ground portion). The adhesion of the image agent can be reduced. Further, in the developing gap portion, the developer is brought into intermittent contact or non-contact with the latent image carrier, thereby reducing unnecessary adhesion of the developer and reducing the image product K. It can be improved.
以下、 茧にこの場合の詳細な実施例を示す。  Hereinafter, a detailed example in this case is shown in FIG.
実施例 H 1  Example H 1
第 1 に示されるような現像装置で、 外径 2 0 M肉厚 1 Mで 6 0極に分割着磁したフユライ ト磁石とその内部 に磁気回路を構成する外径 1 8 ran肉厚 l imeのヨーク とで 磁性体ローラーを構成し、 磁性体口一ラーを 2 0 O rpin で時計方向に回転させた。 一方、 外径 3 O mniの潜像担持 体を 3 0 rpni で磁性体ローラーと同一方向 （時計方向） に回転させて回転させ現像ギヤ ッブを現像剤が潜像担持 体に対して非接触となるように設定して、 画像形成を行 つたところ、 印字部後端の尾引きがなく なり高濃度でコ ン トラス 卜の高い画像を安定して形成するこ とができた t また、 従来のフユライ ト磁石と金属ス リーブを用いたも のに比べ半分以下に軽量化することができた。 A developing magnet as shown in Fig. 1 is a magnet with an outer diameter of 20M and a thickness of 1M, magnetized into 60 poles, and an outer diameter of 18 ran which forms a magnetic circuit inside the magnet. A magnetic roller was constructed with the yoke and the magnetic roller was rotated clockwise by 20 Orpin. On the other hand, a latent image carrier having an outer diameter of 3 Omni is rotated at 30 rpni in the same direction (clockwise) as the magnetic roller, and the developing gear is brought into contact with the latent image carrier so that the developer does not contact the latent image carrier. set so that, when the image forming the single row, could the child form a high concentration in co emissions truss Bok high image becomes no tailing of the printing unit the rear end is stabilized t conventionally The weight was reduced to less than half compared to the one using the fu- rite magnet and metal sleeve.
実施例 H 2  Example H 2
第 1図に示されるような現像装置で、 外径 2 0 BB肉厚 1 . 5 BBで 4 0極に分割着磁したサマリ ウムコバル ト系 の圧縮成形磁石とその内部に磁気回路を構成する外径 1 7 M肉厚 1 ranのヨークとで磁性体ローラーを構成し、 6 一 磁性体ローラーを 5 0 rpi で時計方向に回転させ、 一方 外径 3 0 Mの潜像担持体を 3 O rpin で磁性体ローラーと 同一方向 （時計方向） に回転させて画像形成を行ったと ころ、 印字部後端の尾引きがなく なり高濃度でコン トラ ス トの高い画像を安定して形成することができた。 また、 従来のフェライ ト磁石と金属スリーブを用いたものに比 ベ半分以下に軽量化することができた。 A developing device as shown in Fig. 1 is a compression molded magnet of the samarium cobalt system, which is magnetized into 40 poles with an outer diameter of 20 BB and a thickness of 1.5 BB, and an outer part constituting a magnetic circuit therein. A magnetic roller composed of a yoke with a diameter of 17 M and a thickness of 1 ran, 6 i Rotate the magnetic roller clockwise at 50 rpi, and rotate the latent image carrier with an outer diameter of 30 M in the same direction (clockwise) as the magnetic roller with 3 O rpin to form an image. At the same time, the trailing edge of the printed portion was no longer trailing, and high-density, high-contrast images could be stably formed. Also, the weight was reduced to less than half that of the conventional one using a ferrite magnet and a metal sleeve.
実施^ H 3  Conduct ^ H 3
第 1図に示されるような現像装置で、 外径 1 2 M肉厚 , 1 mnで 4 0極に分割着磁したサマリ ゥムコバルト系の射 出成形磁石とその内部に磁気回路を構成する外径 1 O M 肉厚 1 ranのヨークとで一体に磁性体口一ラーを構成し、 磁性体ローラ一を 5 0 Γ ΡΠ で時計方向に回転させ、 一方 外径 2 0 の潜像担持体を 2 0 rpin で磁性体ローラーと 同一方向 （時計方向） に回転させて画像形成を行ったと ころ、 印字部後端の尾引きがなく なり高濃度でコ ン トラ ス トの高い画像を安定して形成することができた。 また、 磁性体ローラーは従来のフユライ ト磁石と金属スリーブ を用いたものに比べ 4分の 1以下に軽量化することがで きた。  A developing device as shown in Fig. 1, an outer diameter of 12 M thick, a 1 mn, magnetized split-cobalt-based injection-molded magnet, and an outer diameter that constitutes a magnetic circuit inside 1 OM A yoke with a wall thickness of 1 ran is used to form a magnetic roller, and the magnetic roller is rotated clockwise at 50 ° while the latent image carrier having an outer diameter of 20 is rotated by 20 °. When the image is formed by rotating in the same direction (clockwise) as the magnetic roller with rpin, the trailing edge of the printing section is eliminated, and an image with high density and high contrast is formed stably. I was able to. Also, the weight of the magnetic roller can be reduced to less than one-fourth that of the conventional one using a magnet and a metal sleeve.
比較例 H 1  Comparative Example H 1
従来の一成分磁性現像装置で、 外径 2 0 Mの現像剤搬 送部材 （非磁性の金属スリーブ） を用い、 その内部に配 設される磁性体ローラーを外径 1 8 肉厚 5 mmで 8極に - 5 1 - 分割着磁した焼結のフユライ ト磁石で構成し、 外径 3 0 naの潜像担持体を 3 0 rpra で時計方向に回転させ、 現像 剤搬送部材を 2 0 0 rpm で潜像担持体と同一方向 （時計 方向） に回転させ、 磁性体ローラーを 1 0 0 0 rpm で潜 像担持体と同一方向 （時計方向） に回転させて画像形成 を行ったところ、 印字部後端に尾引きを発生しコ ン トラ ス トの低い低解像度の画像しか形成することができなか つた。 た、 磁性体ローラーを軽 S化することはできな »、つた。 The conventional one-component magnetic developing device uses a developer transporting member (non-magnetic metal sleeve) with an outer diameter of 20 M, and a magnetic roller disposed inside it with an outer diameter of 18 mm and a wall thickness of 5 mm. 8 poles -51 1-Composed of split magnetized sintered magnets, the latent image carrier with an outer diameter of 30 na is rotated clockwise at 30 rpra, and the developer transport member is rotated at 200 rpm. The image was formed by rotating the magnetic roller in the same direction (clockwise) as the image carrier and rotating the magnetic roller in the same direction (clockwise) as the latent image carrier at 1000 rpm. In addition, a tail was generated, and only a low-contrast, low-resolution image could be formed. In addition, magnetic rollers cannot be made lighter.
, 比較例 H 2 , Comparative Example H 2
従来の一成分磁性現像装置で、 外径 2 O rniiの現像剤搬 送部材 （非磁性の金属ス リーブ） を用い、 その内部に配 設される磁性体ローラーを外径 1 8 ran肉厚 5 »nで 8極に 分割着磁した焼結のフユライ ト磁石で構成し、 外径 3 0 Mの潜像担持体を 3 0 rpm で時計方向に回転させ、 現像 剤搬送部材を 2 0 0 ΓΡΠΙ で潜像担持体と反対方向 （反時 計方向） に回転させ、 磁性体口—ラーを 1 0 0 0 rpm で 潜像担持体と同一方向 （時計方向） に回転させて画像形 成を行ったところ、 印字部後端に尾引きを発生しコン ト ラス トの低い低解像度の画像しか形成するこ とができな かった。 また、 磁性体ローラーを軽量化することはでき The conventional one-component magnetic developing device uses a developer transport member (non-magnetic metal sleeve) with an outer diameter of 2 O rnii and a magnetic roller installed inside the roller. It is composed of a sintered fine magnet divided into 8 poles at »n. The latent image carrier having an outer diameter of 30 M is rotated clockwise at 30 rpm, and the developer conveying member is rotated at 200 rpm. To rotate in the opposite direction (counter clockwise) to the latent image carrier, and rotate the magnetic roller at 100 rpm in the same direction (clockwise) as the latent image carrier to form an image. As a result, tailing occurred at the rear end of the printed portion, and only low-resolution, low-resolution images could be formed. Also, it is not possible to reduce the weight of the magnetic roller.
7よ力、つた。 7 Power
バイァス電圧の制御  Control of bias voltage
従来の現像装置においては、 現像剂搬送部材で磁界の 変化に伴う現像剤の凹凸 （磁気ブラ シの凹凸） が形成さ れ、 磁石を回転した場合に、 現像ニップ長が磁石の回転 に伴って変動するため磁石の磁極ビツチに起因する現像 ' 度むらが生じる場合がある。 In a conventional developing device, a magnetic field is generated by a developing / transporting member. Irregularities in the developer (magnetic brush irregularities) due to the change are formed, and when the magnet is rotated, the development nip length fluctuates with the rotation of the magnet. May occur.
本発明の現像装置においては、 磁性体ローラーの磁界 を検出するための磁界検出手段と、 この磁界検出手段に よつて検出される磁界の交番に同期して現像バイアス電 圧を変化させるための現像バイアス電圧変化手段を具備 することによって、 上記の問題を解消させることができ ,る。  In the developing device of the present invention, a magnetic field detecting means for detecting a magnetic field of the magnetic roller, and a developing means for changing a developing bias voltage in synchronization with an alternation of a magnetic field detected by the magnetic field detecting means. By providing the bias voltage changing means, the above problem can be solved.
上記の構成によれば、 現像ニップ部分の磁界の交番に 同期して現像バイアスを変化させ、 現像ニップ部分の現 像剤に働く現像力を一定にでき、 現像濃度の変動を低減 できる。  According to the above configuration, the developing bias is changed in synchronization with the alternation of the magnetic field in the developing nip portion, the developing force acting on the developing agent in the developing nip portion can be kept constant, and the fluctuation in the developing density can be reduced.
さらに、 磁石表面で直接現像剤を搬送する磁性体ロー ラーを用いる場合は、 磁石上で現像剤を直接搬送するた め、 磁石の発生する磁界を最も有効に活 fflすることがで き、 磁石と潜像担持体との間で磁界の交番に同期した現 像バイァス電圧を印加することができる。  Furthermore, when using a magnetic roller that transports the developer directly on the surface of the magnet, the developer is transported directly on the magnet, so the magnetic field generated by the magnet can be used most effectively. A current bias voltage synchronized with the alternation of the magnetic field can be applied between the power supply and the latent image carrier.
第 5図は本発明の実施例における現像装置を含む画像 形成装置の断面概観図である。 潜像担持体 1は、 導電性 の支持部 2の上に有機または無機の光導電性を有する感 光層 3を塗膜したものである。 係る感光層 3をコロナ帯 電器等の帯電器 4を用いて帯電した後に画像に応じて光 源 5から出た光を結像光学系 6を通して感光層 3に選択 的に光照射して感光層 3上に電位コン トラス トを得て静 電潜像を形成する。 一方、 現像装置 7は像形成体である 現像剤 8を帯電させかつ円筒状の磁性体ローラー 9で搬 送して潜像担持体 1 と磁性体ローラー 9とが近接する現 像ギヤ ップ部で潜像担持体 1の静電潜像の電位ボテンシ ャル及び現像バイァス電圧印加手段 1 0によるバイアス 圧に じて現像剤 8を現像するものであって、 潜像担 持体 1の静電潜像を現像剤 8により顕像化するものであ る。 静電潜像を顕像化した現像剤 8は、 コロナ放電ゃ電 界ゃ圧力や粘着力を用いた転写器 1 4により記録紙 1 5 に転写し、 加圧や加熱等の手段により現像剤 8を記録紙 1 5に定着して、 記録紙 1 5上に現像剤 8による所望の 画像を得るものである。 第 1図の現像装置において、 磁 性体ローラー 9は供給された現像剂 8を磁気力により保 持し搬送量規制部材 1 1で適量に規制して現像剤 8を搬 送するものであって、 磁性体ローラー 9は円筒状で外周 を複数極に着磁された磁石 1 2と磁石 1 2の内部に配設 され软磁性で円筒状のヨーク （図示せず） とで磁気回路 を構成し磁石 1 2と空隙を介して配設される円筒状で非 磁性の現像剤搬送部材 1 3上に磁界を形成して磁性の現 像剤 8を搬送するもので、 第 5図に示すよ うに、 本実施 例においては、 磁性体ローラー 9に隣接して磁界検出手 段 1 6が配設され現像ギヤ ッブ部の磁石 1 2による磁界 を検出して、 現像ギャ ップ部の磁界による現像阻止力の 変化に応じて交番電圧重 S手段 1 7により現像バイアス 印加手段 1 0に交番電圧を重覺し、 電界による現像力 (クーロン力） と磁界による現像阻止力との差を一定に 保ち、 現像剤 8に作用する力の変動を低铽し、 従って、 磁石 1 2の回転に伴う現像濃度むらを低滅し髙印字品質 の画像を形成することができる。 尚、 磁界検出手段 1 6 の配設 は磁性体ローラー 9の近佼であればよく、 現 像ギヤ ップ位置での磁界に換算して現像力を一定にする ,ベく交番電圧を重畳すればよく、 交番電圧の波形につい ても正弦波や矩形波や鋸歯状波等の種類にかかわらず適 用可能である。 FIG. 5 is a schematic cross-sectional view of an image forming apparatus including a developing device according to the embodiment of the present invention. The latent image carrier 1 is formed by coating an organic or inorganic photoconductive light-sensitive layer 3 on a conductive support 2. After the photosensitive layer 3 is charged using a charger 4 such as a corona charger, the photosensitive layer 3 emits light in accordance with an image. The light emitted from the source 5 is selectively irradiated on the photosensitive layer 3 through the imaging optical system 6 to obtain a potential contrast on the photosensitive layer 3 to form an electrostatic latent image. On the other hand, a developing device 7 charges a developer 8 as an image forming body and transports it by a cylindrical magnetic roller 9 so that the latent image carrier 1 and the magnetic roller 9 are close to each other. Developing the developer 8 in accordance with the potential potential of the electrostatic latent image on the latent image carrier 1 and the bias pressure by the developing bias voltage applying means 10. The latent image is visualized by the developer 8. The developer 8 that visualizes the electrostatic latent image is transferred to a recording paper 15 by a transfer unit 14 using corona discharge, electric field, pressure and adhesive force, and is then transferred to the developer by means such as pressurization or heating. 8 is fixed on the recording paper 15 to obtain a desired image on the recording paper 15 by the developer 8. In the developing device shown in FIG. 1, the magnetic roller 9 holds the supplied developing roller 8 by magnetic force, and conveys the developer 8 by regulating the conveyance amount regulating member 11 to an appropriate amount. The magnetic roller 9 comprises a magnet 12 having a cylindrical shape and the outer circumference of which is magnetized to a plurality of poles, and a magnetic circuit comprising a magnetic yoke (not shown) provided inside the magnet 12. A magnetic field is formed on a cylindrical, non-magnetic developer conveying member 13 disposed through a gap with a magnet 12 to convey a magnetic developer 8, as shown in FIG. In the present embodiment, a magnetic field detecting means 16 is provided adjacent to the magnetic roller 9 and a magnetic field generated by the magnet 12 of the developing gear portion is provided. The alternating voltage is applied to the developing bias applying means 10 by the S means 17 in accordance with the change in the developing inhibiting force due to the magnetic field of the developing gap, and the developing force (Coulomb force) ) And the difference between the development inhibiting force due to the magnetic field is kept constant, the fluctuation of the force acting on the developer 8 is reduced, and therefore the unevenness of the development density due to the rotation of the magnet 12 is reduced, and the image of print quality is reduced. Can be formed. The magnetic field detecting means 16 may be provided as long as it is close to the magnetic roller 9, so that the developing force is converted into a magnetic field at the image gap position to keep the developing force constant. The waveform of the alternating voltage can be applied irrespective of the type of sine wave, rectangular wave, sawtooth wave, and the like.
第 6 A図、 第 6 B図は、 本発明の実施例における交番 電圧の印加状態を示す図であって、 磁化反転の周期の 2 分の 1の周期で交番電圧を印加するもので、 磁気ブラシ 高さの高い磁極中心部が現像ギヤ ップ部を通過する夕ィ ミ ングで現像電界が小さく、 磁気ブラシ高さの低い磁極 間部が現像ギヤ ップ部を通過するタイ ミ ングで現像電界 が大きく なるように交番電圧を重畳することにより、 現 像電界による現像力と磁気力による現像阻止力との差を 一定に保ち磁界の変動による現像濃度むらを低減するこ とができる。  FIGS. 6A and 6B are diagrams showing an applied state of the alternating voltage in the embodiment of the present invention, in which the alternating voltage is applied at a half cycle of the magnetization reversal cycle. The developing electric field is small at the time when the center of the magnetic pole with the high brush height passes through the developing gap, and the developing is performed at the time when the magnetic pole with the low magnetic brush height passes through the developing gap. By superimposing the alternating voltage so as to increase the electric field, the difference between the developing force due to the current electric field and the developing inhibiting force due to the magnetic force can be kept constant, and the unevenness in the developing density due to the fluctuation of the magnetic field can be reduced.
磁界検出手段としては、 ホール素子や磁気抵抗素子や コイル等で公知の素子はもとより、 磁石の回転位置を検 知する光学式のェンコウダ一やメカニカルスィ ツチ等を 用いて間接的に磁界 （磁石の回転位饈） を検出しても同 様に交番電圧の重登ができることは明白である。 The magnetic field detecting means detects not only known elements such as a Hall element, a magnetoresistive element, and a coil, but also the rotational position of the magnet. It is clear that the alternating voltage can be similarly increased even if the magnetic field (magnet rotation position 饈) is detected indirectly by using a known optical encoder or mechanical switch.
以下、 さらに詳細な実施例を示す。  Hereinafter, more detailed examples will be described.
実施例 I 1  Example I 1
第 5図に示されるような現像装置で、 現像剤搬送部材 上の磁束密度が 8 0 0 [ G ] で 8極に着磁された磁石を 用いた磁性体ローラーで現像剤を搬送し、 潜像担持体に 有機感光体を用いて、 磁界検出手段を現像ギャ ップ近傍 に配設し、 現像バイアス電圧を一 5 5 0 [ V ] の直流成 分に ± 2 0 0 [ V ] の交流成分を磁界の変化周波数の 2 倍の周波数で磁極の中心が現像ギヤ ップ中心を通過する ときに現像バイアス ¾圧の絶対値が小さく なるように交 番電圧を重置し反転現像により画像形成を行ったところ、 ベタ画像の現像濃度むらがなく、 細線の線幅の変化が小 さい高印字品質の画像を形成することができた。  In a developing device as shown in FIG. 5, the magnetic flux density on the developer conveying member is 800 [G], and the developer is conveyed by a magnetic roller using magnets magnetized to eight poles, and the latent image is transferred to the developing device. Using an organic photoreceptor as the image carrier, a magnetic field detecting means is arranged near the developing gap, and the developing bias voltage is applied to a DC component of 550 [V] and an AC of ± 200 [V]. When the center of the magnetic pole passes through the center of the developing gap at twice the frequency of the magnetic field change frequency, the alternating voltage is superimposed so that the absolute value of the developing bias ¾ pressure is reduced, and image formation is performed by reversal development. As a result, it was possible to form an image of high print quality with no unevenness in the development density of the solid image and a small change in the line width of the fine line.
実施例 I 2  Example I 2
第 5図に示されるような磁性体ローラーで磁石上の磁 朿密度が 4 0 0 [ G ] で 3 2極に ¾磁された希土類の磁 石を用いて現像剤を直接搬送し磁界の検出を磁性体ロー ラー端部の光学式ェンコーダ一で間接的に検出すること を除いては実施例 I 1 と同様の構成で画像形成を行った ところ、 ベタ画像の現像濃度むらがなく、 細線の線幅の 変化が小さい高印字品質の画像を形成する；とができた。 比較例 I 1 Using a magnetic roller as shown in Fig. 5, the developer is directly transported using a rare earth magnet magnetized to 32 poles with a magnetic density of 400 [G] on the magnet, and the magnetic field is detected. An image was formed using the same configuration as in Example I1 except that the optical encoder at the end of the magnetic roller was used to indirectly detect the density of the solid image. A high print quality image with a small change in line width was formed; Comparative Example I 1
交番電圧を印加しないことを除いては卖施例 I 1 と同 様の構成で画像形成を行ったところ、 ベタ画像に磁界の 変化に対応した現像濃度むらが発生し、 細線の線幅の変 化が著しい低印字品質で階調性に乏しい画像しか得られ なかった。  An image was formed using the same configuration as in Example I1 except that no alternating voltage was applied.As a result, uneven development density corresponding to the change in the magnetic field occurred in the solid image, and the line width of the fine line changed. Only images with poor print quality and poor gradation were obtained.
比铰例 I 2  Comparative example I 2
現像^ィァス電圧を一 5 5 0 [ V ] の直流成分に土 1 0 0 0 [ V ] の交番電圧で交番電圧の周波数が磁界の ，変化周波数の約 1 0倍 （数キロ H z ) となるように fi暨 して印加することを除いては、 実施例 I 1 と同様の構成 で画像形成を行ったところ、 ベタ画像の現像濃度むらは 比較例 I 1 と同様に発生し、 階調性に乏しい画像しか得 られなかった。  The developing bias voltage is changed to a DC component of 1550 [V] with an alternating voltage of 10000 [V], and the frequency of the alternating voltage is about 10 times (several kiloHz) the change frequency of the magnetic field. An image was formed with the same configuration as in Example I1 except that the voltage was applied in such a manner as to obtain a uniform image. Only poor quality images were obtained.
産橥上の利用可能性  Industrial availability
本発明の現像装置は、 電子写真プロセスを用いた画像 記録手段に広く使用することができ、 特にプリ ン夕一、 複写機あるいはファクシミ リなどの現像装置として広く 適用することができる。  INDUSTRIAL APPLICABILITY The developing device of the present invention can be widely used for image recording means using an electrophotographic process, and can be particularly widely applied as a developing device for a printing machine, a copying machine or a facsimile machine.

Claims

請 求 の 範 囲 The scope of the claims
1 . 電子写真プロセスを用いた画像記録装置におい て潜像担持体に形成された静電潜像パターンを現像する ための現像装置であつて、 1. A developing device for developing an electrostatic latent image pattern formed on a latent image carrier in an image recording apparatus using an electrophotographic process,
複数の磁極が着磁され、 希土類磁石からなる円筒状の 磁性体ローラーを具備し、 この磁性体ローラー上に現像 剤を直接供給して磁性体ローラーにより発生する磁場に よって前記現像剤を磁性体ローラー表面に保持するとと もに、 前記磁性体ローラ一を回転させて前記保持された 現像剤を搬送するようにしたことを特徴とする、 現像装  A plurality of magnetic poles are magnetized, and a cylindrical magnetic roller made of a rare earth magnet is provided. The developer is directly supplied to the magnetic roller, and the developer is magnetically generated by a magnetic field generated by the magnetic roller. A developing device that holds the developer by rotating the magnetic roller one while holding the developer on the surface of the roller.
2 . 前記円筒状の磁性体ローラーの内面側に钦磁性 材料からなるヨークが積層形成されてなる、 請求項 1 に 記載の現像装置。 2. The developing device according to claim 1, wherein a yoke made of a diamagnetic material is laminated on an inner surface of the cylindrical magnetic roller.
3 . 前記磁性体ローラーが、 庄縮成形、 射出成形、 または押出成形によつて成形された希土類磁石からなる、 請求項 1に記載の現像装置。  3. The developing device according to claim 1, wherein the magnetic roller is made of a rare earth magnet formed by shrink molding, injection molding, or extrusion molding.
4 . 前記磁性体ローラーが、 1 0極以上の磁極に分 割 @磁されてなる、 請求孭 1 に記載の現像装置。  4. The developing device according to claim 1, wherein the magnetic roller is divided into at least 10 magnetic poles and magnetized.
5 . 前記磁性体ローラーの表面に凹凸が形成されて なる、 請求項 1 に記載の現像装置。  5. The developing device according to claim 1, wherein irregularities are formed on a surface of the magnetic roller.
6 . 前記磁性体ローラー表面の凹凸が、 磁極ピッチ に対応して形成されたものであつて、 磁極 中心部分を 凹部とし、 かつ、 磁極と磁極の境界部分を凸部にした、 請求項 5に記載の現像装置。 6. The irregularities on the surface of the magnetic roller are formed in correspondence with the magnetic pole pitch, and the center of the magnetic pole is 6. The developing device according to claim 5, wherein the developing device has a concave portion and a boundary portion between the magnetic poles is a convex portion.
7. 前記磁性体ローラーの表面粗さが、 J I S規格 の 1 0点平均粗さ （ J I S - B 060 1 ) の表示に基づ いて、 現像剤の構成要素である トナーの体積平均粒子径 の 40%以下である、 請求項 1に記載の現像装置。  7. The surface roughness of the magnetic roller is determined based on the 10-point average roughness (JIS-B0601) of the JIS standard. The developing device according to claim 1, wherein the ratio is not more than%.
8. 前記磁性体口一ラーの表面に被覆層が形成され てなる、'請求項 1に記載の現像装匿。  8. The developing and concealing method according to claim 1, wherein a coating layer is formed on a surface of the magnetic substance aperture.
9. 前記被覆層が、 導電性材料からなる、 請求項 8 に記載の現像装置。  9. The developing device according to claim 8, wherein the coating layer is made of a conductive material.
10. 前記被覆層が、 樹脂からなる、 請求項 8に記 載の現像装置。  10. The developing device according to claim 8, wherein the coating layer is made of a resin.
1 1. 前記被覆層が、 無機化合物からなる、 請求項 8に記載の現像装置。  1 1. The developing device according to claim 8, wherein the coating layer is made of an inorganic compound.
12. 前記現像装置が、 前記磁性体ローラーの表面 に少なく とも部分的に圧接されるように配置した現像剤 搬送量規制部材を具備している、 請求項 1 に記載の現像 装置。  12. The developing device according to claim 1, wherein the developing device includes a developer conveyance amount regulating member disposed so as to be at least partially pressed against the surface of the magnetic roller.
1 3. 前記磁性体ローラーの表面と、 前記現像剤搬 送 S規制部材とが面接触し、 かつ、 前記現像剂搬送量規 制部材の端部が前記磁性体ローラーに非接触である、 請 求項 1に記載の現像装置。  1 3. The surface of the magnetic roller and the developer transport S regulating member are in surface contact with each other, and the end of the developing / transporting amount regulating member is not in contact with the magnetic roller. The developing device according to claim 1.
14. 前記磁性体ローラーが薄肉円筒状であり、 か つ、 その内部が実質的に中空構造からなる、 請求項 1に 記載の現像装置。 14. The magnetic roller according to claim 1, wherein the magnetic roller has a thin cylindrical shape, and the inside thereof has a substantially hollow structure. The developing device as described in the above.
1 5 . 前記磁性体ローラーの回転方向と前記潜像担 持体の回転方向とを同一方向に設定した、 請求項 1 に記 載の現像装置。  15. The developing device according to claim 1, wherein the rotation direction of the magnetic roller and the rotation direction of the latent image carrier are set to the same direction.
1 6 . 前記磁性体ローラーの回転方向と前記潜像担 持休の回転方向とを逆方向に設定し、 かつ、 前記磁性体 ローラーの周逨度が、 前記潜像担持体の周速度より も逑 く なる ^うに設定した、 請求項 1 に記載の現像装！:。  16. The rotation direction of the magnetic roller and the rotation direction of the latent image holding member are set in opposite directions, and the peripheral speed of the magnetic roller is lower than the peripheral speed of the latent image carrier. The developing device according to claim 1, wherein the developing device is set to a different shape. :.
1 7 . 前記現像装置が、 前記磁性体ローラーの磁界 ，を検出するための磁界検出手段と、 この磁界検出手段に よって検出される磁界の交番に同期して現像バイアス電 圧を変化させるための現像バイアス電圧変化手段を具備 している、 請求頃 1に記載の現像装置。  17. The developing device comprises: a magnetic field detecting means for detecting a magnetic field of the magnetic roller; and a developing bias voltage for changing a developing bias voltage in synchronization with an alternation of a magnetic field detected by the magnetic field detecting means. 2. The developing device according to claim 1, further comprising a developing bias voltage changing unit.
1 8 . 電子写真プロセスを用いた画像記録装置にお いて潜像担持体に形成された静電潜像パターンを現像す るための現像装置であって、  18. A developing device for developing an electrostatic latent image pattern formed on a latent image carrier in an image recording apparatus using an electrophotographic process,
複数の磁極が着磁されてなり、 表面に凹凸が形成され てなる円筒状の磁性体ローラーを具備し、 この磁性体口 —ラー上に現像剤を直接供給して磁性休ローラーにより 発生する磁場によつて前記現像剤を磁性体ローラー表面 に保持するとともに、 前記磁性体ローラーを回転させて 前記保持された現像剤を搬送するようにしたことを特徴 とする、 現像装匿。  It has a cylindrical magnetic roller with a plurality of magnetic poles magnetized and irregularities formed on the surface. The magnetic field generated by the magnetic idle roller by directly supplying the developer onto the magnetic roller The developer is held on the surface of the magnetic material roller, and the magnetic material roller is rotated to transport the held developer.
1 9 . 前記円筒状の磁性体ローラーの内面側に钦磁 性材料からなるヨークが積層形成されてなる、 請求項 18に記載の現像装匾。 1 9. Magnetize the inner surface of the cylindrical magnetic roller 19. The developing device according to claim 18, wherein a yoke made of a conductive material is formed by lamination.
20. 前記磁性体ローラ—が、 1 0極以上の磁極に 分割着磁されてなる、 請求項 18に記載の現像装 a。  20. The developing device a according to claim 18, wherein the magnetic roller is divided and magnetized into 10 or more magnetic poles.
21. 前記磁性体ローラ一表面の凹凸が、 磁極ビッ チに対応して形成されたものであって、 磁極の中心部分 を凹部とし、 かつ、 磁極と磁極の境界部分を凸部にした、 請求項 18に記載の現像装置。  21. The unevenness on one surface of the magnetic roller is formed so as to correspond to the magnetic pole bit, wherein the central portion of the magnetic pole is a concave portion, and the boundary portion between the magnetic poles is a convex portion. Item 19. The developing device according to Item 18.
•22. 前記磁性体ローラーの表面粗さが、 J I S規 ,格の 10点平均粗さ （ J I S - B 060 1 ) の表示に基 づいて、 現像剤の構成要素である トナーの休積平均粒子 径の 40%以下である、 請求項 18に記載の現像装置。  • 22. Based on the 10-point average roughness (JIS-B0601), the surface roughness of the magnetic roller is based on the average particle size of toner, which is a component of the developer. 19. The developing device according to claim 18, wherein the diameter is 40% or less of the diameter.
23. 前記磁性体ローラーの表面に被 ¾層が形成さ れてなる、 請求項 18に記載の現像装置。  23. The developing device according to claim 18, wherein a coating layer is formed on a surface of the magnetic roller.
24. 前記被覆層が、 導電性材料からなる、 請求項 18に記載の現像装置。  24. The developing device according to claim 18, wherein the coating layer is made of a conductive material.
25. 前記被覆層が、 樹脂からなる、 請求項 18に 記載の現像装置。  25. The developing device according to claim 18, wherein the coating layer is made of a resin.
26. 前記被覆層が、 無機化合物からなる、 請求項 18に記載の現像装匿-。  26. The development concealing device according to claim 18, wherein the coating layer is made of an inorganic compound.
27. 前記現像装置が、 前記磁性体ローラーの表面 に少なく とも部分的に圧接されるように配置した現像剤 搬送量規制部材を具備している、 請求項 18に記載の現 像装置。 _ 27. The developing device according to claim 18, wherein the developing device includes a developer conveyance amount regulating member disposed so as to be at least partially pressed against the surface of the magnetic roller. _
2 8 . 前記磁性体ローラーの表面と、 前記現像剤搬 送量規制部材とが面接触し、 かつ、 前記現像剤搬送 S規 制部材の端部が前記磁性体ローラーに非接触である、 請 求項 1 8に記載の現像装置。 28. The surface of the magnetic roller and the developer carrying amount regulating member are in surface contact with each other, and the end of the developer carrying S regulating member is not in contact with the magnetic roller. The developing device according to claim 18.
2 9 . 前記磁性体ローラーが薄肉円筒状であり、 か つ、 その内部が実質的に中空構造からなる、 請求頃 1 8 に記載の現像装置。  29. The developing device according to claim 18, wherein the magnetic roller has a thin cylindrical shape, and the inside thereof has a substantially hollow structure.
3 0 . " 前記磁性体ローラーの回転方向と前記潜像担 持体の回転方向とを同一方向に設定した、 請求項 1 8に ,記載の現像装置。  30. The developing device according to claim 18, wherein the rotation direction of the magnetic roller and the rotation direction of the latent image carrier are set to the same direction.
3 1 . 前記磁性体ローラーの回転方向と前記潜像担 持体の回転方向とを逆方向に設定し、 かつ、 前記磁性体 ローラーの周速度が、 前記潜像担持体の周速度より も速 く なるように設定した、 請求項 1 8に記載の現像装置。  31. The rotation direction of the magnetic roller and the rotation direction of the latent image carrier are set in opposite directions, and the peripheral speed of the magnetic roller is faster than the peripheral speed of the latent image carrier. The developing device according to claim 18, wherein the developing device is set so as to have a smaller number.
3 2 . 前記現像装置が、 前記磁性体ローラーの磁界 を検出するための磁界検出手段と、 この磁界検出手段に よつて検出される磁界の交番に同期して現像バイァス電 圧を変化させるための現像バイアス電圧変化手段を具備 している、 請求項 1 8に記載の現像装置。  32. The developing device, comprising: a magnetic field detecting means for detecting a magnetic field of the magnetic roller; and a developing bias voltage for changing a developing bias voltage in synchronization with an alternation of a magnetic field detected by the magnetic field detecting means. 19. The developing device according to claim 18, further comprising a developing bias voltage changing unit.
3 3 . 電子写真プロセスを用いた画像記録装置にお いて潜像担持体に形成された静電潜像パターンを現像す るための現像装置であつて、  33. A developing device for developing an electrostatic latent image pattern formed on a latent image carrier in an image recording apparatus using an electrophotographic process,
複数の磁極が眷磁されてなる円筒状の磁性体ローラー を具備し、 この磁性体ローラー上に現像剂を直接供給し て磁性体ローラーにより発生する磁場によつて前記現像 剤を磁性体ローラー表面に保持するとともに、 前記磁性 体ローラーを回転きせて前記保持された現像剤を ¾送す るようにしたことを特徴とする、 現像装置。 It has a cylindrical magnetic roller in which a plurality of magnetic poles are magnetized, and the developer is directly supplied on the magnetic roller. And holding the developer on the surface of the magnetic roller by a magnetic field generated by the magnetic roller, and rotating the magnetic roller to feed the held developer. Developing device.
3 4 . 前記円筒状の磁性体ローラーの內面側に钦磁 性材料からなるヨークが積層形成されてなる、 請求項  34. A yoke made of a magnetic material is laminated on one surface of the cylindrical magnetic roller.
3 3に記載の現像装置。  33. The developing device according to 3.
3 5 . " 前記磁性体ローラーが、 1 0極以上の磁極に 分割着磁されてなる、 請求項 3 3に記載の現像装置。 35. The developing device according to claim 33, wherein the magnetic roller is divided and magnetized into 10 or more magnetic poles.
, ,
3 6 . 前記磁性体ローラーの表面粗さが、 J I S規 格の 1 0点平均粗さ （ J I S - B 0 6 0 1 ) の表示に基 づいて、 現像剤の構成要素である トナーの体積平均粒子 径の 4 0 %以下である、 請求項 3 3に記載の現像装置。 36. The surface roughness of the magnetic roller is based on the 10-point average roughness (JIS-B0601) of the JIS standard. The developing device according to claim 33, wherein the particle size is 40% or less of the particle size.
3 7 . 前記磁性体ローラーの表面に被覆層が形成さ れてなる 請求項 3 3に記載の現像装置。  37. The developing device according to claim 33, wherein a coating layer is formed on a surface of the magnetic roller.
3 8 . 前記被覆層が、 導電性材料、 樹脂および無機 化合物からなる群から選ばれた少なく とも 1種からなる、 請求項 3 7に記載の現像装置。  38. The developing device according to claim 37, wherein the coating layer is made of at least one selected from the group consisting of a conductive material, a resin, and an inorganic compound.
3 9 . 前記現像装置が、 前記磁性体ローラーの表面 に少なく とも部分的に圧接されるように配置した現像剤 搬送量規制部材を具備している、 請求項 3 3に記載の現 像装置。  39. The developing device according to claim 33, wherein the developing device includes a developer conveyance amount regulating member disposed so as to be at least partially pressed against the surface of the magnetic roller.
4 0 . 前記磁性体ローラーの表面と、 前記現像剤搬 送量規制部材とが面接触し、 かつ、 前記現像剤搬送量規 制部材の端部が前記磁性体ローラ一に非接触である、 請 求項 3 3に記載の現像装置。 40. The surface of the magnetic roller is in surface contact with the developer transport amount regulating member, and the developer transport amount regulator is 34. The developing device according to claim 33, wherein an end of the control member is not in contact with said magnetic roller.
4 1 . 前記磁性体ローラーの回転方向と前記潜像担 持体の回転方向とを逆方向に設定し、 かつ、 前記磁性体 ローラーの周速度が、 前記潜像担持体の周速度より も逨 く なるように設定した、 請求項 3 3に記載の現像装匿。  41. The rotation direction of the magnetic roller and the rotation direction of the latent image carrier are set in opposite directions, and the peripheral speed of the magnetic roller is smaller than the peripheral speed of the latent image carrier. 34. The developing and concealing device according to claim 33, wherein the developing device is set so as to be invisible.
4 2 . 前記現像装置が、 前記磁性体ローラーの磁界 を検出するための磁界検出手段と、 この磁界検出手段に よって検出される磁界の交番に同期して現像バイアス電 ，圧を変化させるための現像バイアス電圧変化手段を具備 している、 請求項 3 3に記載の現像装置。  42. The developing device, comprising: a magnetic field detecting means for detecting a magnetic field of the magnetic roller; and a developing bias voltage and a pressure for changing a developing bias voltage and a pressure in synchronization with an alternation of a magnetic field detected by the magnetic field detecting means. The developing device according to claim 33, further comprising a developing bias voltage changing unit.
PCT/JP1990/000808 1989-06-21 1990-06-20 Developing apparatus WO1990016017A1 (en)

Applications Claiming Priority (22)

Application Number Priority Date Filing Date Title
JP15891989A JPH0324574A (en) 1989-06-21 1989-06-21 Developing device
JP1/158919 1989-06-21
JP1/172335 1989-07-04
JP17233989A JPH0337689A (en) 1989-07-04 1989-07-04 Developing device
JP17233589A JPH0336571A (en) 1989-07-04 1989-07-04 Developing device
JP1/172336 1989-07-04
JP1/172334 1989-07-04
JP17233489A JPH0336575A (en) 1989-07-04 1989-07-04 Developing device
JP17233389A JPH0336574A (en) 1989-07-04 1989-07-04 Developing device
JP1/172333 1989-07-04
JP17233789A JPH0336573A (en) 1989-07-04 1989-07-04 Developing device
JP1/172339 1989-07-04
JP1/172338 1989-07-04
JP17233689A JPH0336572A (en) 1989-07-04 1989-07-04 Developing device
JP17233889A JPH0337690A (en) 1989-07-04 1989-07-04 Developing device
JP1/172337 1989-07-04
JP17952289A JPH0344674A (en) 1989-07-12 1989-07-12 Developing device
JP17950789A JPH0343766A (en) 1989-07-12 1989-07-12 Developing device
JP1/179507 1989-07-12
JP1/179521 1989-07-12
JP1/179522 1989-07-12
JP17952189A JPH0344673A (en) 1989-07-12 1989-07-12 Developing device

Publications (1)

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WO1990016017A1 true WO1990016017A1 (en) 1990-12-27

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PCT/JP1990/000808 WO1990016017A1 (en) 1989-06-21 1990-06-20 Developing apparatus

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WO (1) WO1990016017A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5319337A (en) * 1991-04-05 1994-06-07 Kanegafuchi Kagaku Kogyo Kabushiki Kaisha Composite molding of resin-bonded magnet for machine parts and process for producing the same
CN1051452C (en) * 1994-07-26 2000-04-19 中国医学科学院血液学研究所 Application of 3-substituted aryl oxidized indole compounds

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS50115040A (en) * 1974-01-07 1975-09-09
JPS52140334A (en) * 1976-05-19 1977-11-22 Hitachi Metals Ltd Electrostatic image developing apparatus
JPS56113172A (en) * 1980-02-12 1981-09-05 Canon Inc Development device
JPS60216512A (en) * 1984-04-12 1985-10-30 Seiko Epson Corp Magnet for magnetic roll
JPS62201463A (en) * 1986-02-28 1987-09-05 Hitachi Metals Ltd Developing method
JPH05152831A (en) * 1991-11-29 1993-06-18 Toko Inc Resonance frequency adjustment method for microstrip antenna

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS50115040A (en) * 1974-01-07 1975-09-09
JPS52140334A (en) * 1976-05-19 1977-11-22 Hitachi Metals Ltd Electrostatic image developing apparatus
JPS56113172A (en) * 1980-02-12 1981-09-05 Canon Inc Development device
JPS60216512A (en) * 1984-04-12 1985-10-30 Seiko Epson Corp Magnet for magnetic roll
JPS62201463A (en) * 1986-02-28 1987-09-05 Hitachi Metals Ltd Developing method
JPH05152831A (en) * 1991-11-29 1993-06-18 Toko Inc Resonance frequency adjustment method for microstrip antenna

Also Published As

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