US3552355A - Development apparatus - Google Patents

Development apparatus Download PDF

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Publication number
US3552355A
US3552355A US723041A US3552355DA US3552355A US 3552355 A US3552355 A US 3552355A US 723041 A US723041 A US 723041A US 3552355D A US3552355D A US 3552355DA US 3552355 A US3552355 A US 3552355A
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United States
Prior art keywords
magnetic
development
image
latent image
developer
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US723041A
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English (en)
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Thomas J Flint
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Xerox Corp
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Xerox Corp
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    • 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

Definitions

  • ABSTRACT A developing apparatus for applying toner amongctrocles to a photoconductive surface carrying a latent el 1305b 5/00 static image.
  • the apparatus comprises a transport roll having a 1 13/637, developer coating made up of magnetic toner material which is moved first past a charging device which applies a uniform charge to the surface of the coating of a polarity opposite that of the latent image and then wave forming elements which cause an undulation of the surface of the coating while in close proximity with the latent image.
  • a rotating linear magnet Field 346/(lnquired); /(lnquired) S T N m MA .IP S me m T S e m n N U 0 U device is disposed interior of the roll for effecting oscillating movement of the wave forming elements and ⁇ for enhancing fluidization of the developer material during develo the latent images.
  • TTOFPNEVS DEVELOPMENT APPARATUS This invention relates to electrostatographic copying and, particularly, to an improved apparatus for the deposition of visible powder material on an electrostatic latent image as in the development of a xerographic image or the like.
  • xerography it is usual to form an electrostatic image on a sensitized surface.
  • One method of doing this is to charge a photoconductive insulating surface and then dissipate the charge selectively by exposure to a pattern of activating radiation as set forth, for instance, in US. Pat. No. 2,297,691 to Chester F. Carlson. Whether formed by this means or any other, the resulting electrostatic charge pattern is conventionally developed by the deposition of an electroscopic material thereon through electrostatic attraction whereby there is formed a visible image of electroscopic particles corresponding to the electrostatic image.
  • a common process of applying the developer to the electrostatic image described in US. Pat. No. 2,618,552 to E. N. Wise involves cascading a finely divided colored material called a toner deposited on a slightly more coarsely divided material called a carrier" across the electrostatic image areas.
  • the toner and carrier being rubbed against each other while cascading, impart an electrostatic charge to each other by triboelectric charging.
  • a carrier particle bearing on its surface oppositely charged particles of toner, across an area on the image surface having an electrostatic charge, the charge on the surface exerts greater attraction for the toner than does the carrier and retains the toner in' the charged areas and separates it from the carrier particles.
  • the carrier particles being oppositely charged and having greater momentum, will not be retained by the charged areas of the plate.
  • the electrostatic attraction of the carrier particles for the toner particles is sufficient to retain the toner on the carrier preventing deposition in such areas as the carrier particles momentum carries both toner and carrier past.
  • cascade carrier development has a high development latitude and is particularly noteworthy in freedom from background deposition. Further, the process is dependable, operates with high efficiency under extreme humidity conditions and is easily converted to give either positive or reverse reproduction of the original to be copied. The process also has certain limitations. Thus, cascade carrier development gives little or no solid area coverage, that is, solid colored areas such as those presented by block letters develop only around the periphery leaving a white or undeveloped area in the center. Again, relying largely on gravity to move the carrier across the image-bearing surface, the
  • a granular carrier is selected having ferromagnetic properties and selected relative to the toner in a triboelectric series so as to impart the desired electrostatic polarity to the toner and carrier as in cascade carrier development.
  • the carrier particles align themselves along the lines of force of the magnet to assume a brushlike array.
  • the toner particles are electrostatically coated on the surface of the granular magnetic carrier particles.
  • Development proceeds as in regular cascade carrier development on moving the magnet over the surface bearing the electrostatic image so that the bristles" of the magnetic brush contact the electrostatic image-bearing surface.
  • Magnetic carrier development gives good coverage of solid areas and is eminently suitable for machine application by reason of the greater compactness of the developer system and freedom from dependence on gravity which limits the placement of a cascade carrier system around a rotary drum.
  • magnetic development is inherently less efficient than cascade development ln magnetic development only part of the brush contacts the image-bearing surface.
  • the magnetic field restricts the motion of the carrier particles interfering with the individual toner particles smoothly rolling across the image surface.
  • a higher concentration of toner is generally essential in magnetic carrier development.
  • the process gives a high background deposition and is generally characterized by poor development latitude.
  • FIG. 1 is a schematic sectional view of a typical xerographic reproduction machine embodying the principles of the invention
  • FIG. 2 is a side sectional view of the development apparatus according to the present invention.
  • FIG. 3 is an end sectional view of the development apparatus taken along line 3-3 of FIG. 2;
  • FIG. 5 is an isometric view partly broken away of the development apparatus.
  • FIG. 1 For a general understanding of a typical xerographic processing system in which the invention may be incorporated, reference is made to FIG. 1 in which various components of a typical system are schematically illustrated.
  • a light image of an original to be reproduced is projected onto the sensitized surface of a xerographic plate to form an electrostatic latent image thereon.
  • the latent image is developed with the same or an oppositely charged developing toner material, depending upon negative-to-positive or positive-to-positive mode of reproduction, to form a xerographic powder image corresponding to the latent image on the plate surface.
  • the xerographic reproduction machine includes an exposure station at which a light or radiation pattern of a document to be reproduced is projected by a lens 11 onto an electrostatographic surface, such as a xerographic drum 12.
  • the xerographic drum 12 is detachably secured to a shaft 13 mounted in suitable bearings in the frame of the machine. and is driven in a counterclockwise direction by a motor at a constant rate that is proportional to the scan rate for the document being reproduced whereby the peripheral rate of the drum surface is identical to the rate of movement of the progjected light image of the document.
  • the drum surface comprises a layer of photoconductive material on a conductive the electrostatic latent image passes through a developing station in which there is positioned a developer apparatus 16 in accordance with the present invention as will be described hereinafter.
  • the image transfer station Positioned next and adjacent to the developing station is the image transfer station which includes a pair of rollers 18 for i-holding a support material in the form of paper web P against the surface of the drum to receive the developed xerographic powder image therefrom.
  • the web P is moved in synchronism with the rotation of the drum by means of a takeup roll 20 which drives the support material P from a supply roll 22.
  • a suitable drive mechanism (not shown) is connected to the drum 12 for imparting rotation thereto at a continuous speed.
  • This drive mechanism may be connected to the takeup roll 20 for imparting rotation thereto thereby producing movement of the web material P in the same peripheral direction and at the same speed as the peripheral surface of the drum.
  • a suitable programming device may be utilized to effect continuous synchronous movement of these surfaces.
  • the transfer of the xerographic powder image from the drum surface to the transfer material is effected by means of a corona transfer device 23 that is located at place of contact 'between the transfer material and the rotating drum.
  • corona transfer device 23 is substantially similar to the corona discharge device 14 in that'it includes an array of one or more image from the drum surface and cause them to adhere electrostatically to the surface of the transfer material.
  • the transfer material is carried to a fixing device in the form of a fuser assembly 25 whereby the developed and transferred xerographic powder image on the sheet material P is permanently fixed thereto.
  • the finished copy is preferably discharged from the apparatus at a suitable point for collection externally of the apparatus.
  • the next and final station in the device is a drum cleaning station having positioned therein a corona precleaning device 26 similar to the corona charging device l4 of appropriate polarity, negative for positive-to-positive mode of reproduction and positive for negative-to-positive mode of reproduction, to impose an electrostatic charge on the drum and residual powder adherent thereto to aid in effecting removal of the powder and a drum cleaning device under suction in the form of a rotary brush 2'! adapted to remove any powder remaining on the xerographic drum.
  • a corona precleaning device 26 similar to the corona charging device l4 of appropriate polarity, negative for positive-to-positive mode of reproduction and positive for negative-to-positive mode of reproduction, to impose an electrostatic charge on the drum and residual powder adherent thereto to aid in effecting removal of the powder and a drum cleaning device under suction in the form of a rotary brush 2'! adapted to remove any powder remaining on the xerographic drum.
  • the electrostatic charging of the xerographic drum in preparation for the exposure step and the electrostatic charging of the support surface to effect toned image transfer are accomplished by means of corona generating devices whereby electrostatic charge on the order of from 700 to 1000 volts is measured on the respective surface in each instance.
  • a corona charging device of the type disclosed in Vyverberg U.S. Pat. No. 2,836,725 is used for both the corona charging device 14 and the corona transfer device 23, each of which is secured to suitable frame elements of the apparatus and connected to a suitable electrical circuit.
  • Development apparatus 16 comprises a frame 50 on which there is a trough 51 for containing a supply of magnetic toner material 53.
  • Magnetic toner material is made up of two components, one of which is magnetic particle and the other which is an electroscopic marking resin powder. Any suitable electroscopic marking resin powder can be used such as those described in U.S. Pat. No. 2,618,551 to Walkup, U.S. Pat. No. 2,618,552 to Wise and U.S. Pat. No. 2,638,416 to Walkup and Wise.
  • the magnetic component should be a material which will respond to a low or high frequency magnetic field so that it will readily transfer the electroscopic binder and preferably can be heated, thereby causing the electroscopic component of the developer to melt or flow and become attached to the transferred material.
  • Magnetic materials suitable for the purposes of the present invention are magnetic iron and its alloys, such as nickel-iron alloys, nickel-cobalt-iron alloys, and magnetic oxides, such as hematite (Fe,0 and magnetite (Fe t),) and ferromagnetic ferrites.
  • Cobalt and its alloys are also useful, such as, for example, aluminum-nickel-cobalt, coppernickel-cobalt, and cobalt-platinum-manganese alloys.
  • a preferred magnetic material comprises iron oxide particles under the trademark of I.R.N. 0100 manufactured by CK. Williams Division ofCharles Phizer Co.
  • the magnetic component should be finely divided as this enables it to be readily mixed or coated with the electroscopic binder component and greatly increases its pigment value. Also the magnetic component should be substantially coated or firmly attached to a relatively larger amount, areawise, of the electroscopic component in order that the powdervwill readily be influenced by and develop electrostaticvimages since the magnetic component itself may not be susceptible to electrostatic charges and not, by itself, developed. Particles sizes of l to 20 microns have been found satisfactory for producing good, clear dense pictures.
  • the resin containing the magnetic component will respond to the electrical charges on the plate and thereby develop a picture even if the magnetic component not be electroscopic. Also, there should be sufficient resin present to hold the magnetic portion when the powder is transferred and fixed.
  • the magnetic material should be present in an amount sufficient to respond to the electromagnetic field and to carry the resin through such a field, as well as to have a mass or volume to provide, under the influence of a high frequency electromagnetic field, sufficient heat to fuse or flow the resin attached to it. lt has been found that the ratio of binder or resin to the magnetic component can vary from 19 to l to 2 to 3. For the best results, there should be at least percent by weight of the magnetic particles, but not over 70 percent by weight, as the higher amounts may contain too little binder to satisfactorily secure the magnetic portion of the transferred media.
  • Magnetic toner material 53 can be readily prepared by first finely dividing or crushing the resin material, after which it is mixed with the magnetic material. Thorough mixing is necessary in order to insure that the magnetic particles have been entirely encased with the binder. The mixed resin and magnetic powders are melted and stirred to thoroughly disperse the magnetic powder in the resin. The mass is then permitted to cool, and preferably is mixed on a rubber mill where the heated rollers assure sufficient plasticity to blend the components thoroughly, after which it is broken into small chunks and again subdivided. it is thenmicronized and sieved to size. Obviously, other methods can readily be devised by those skilled in the art for the production of extremely fine pigmented resin powders of this type where the pigment particles are magnetic in character.
  • a transport roll 57 which serves tomove the toner material from trough 51 into the image development zone.
  • Roll 57 comprises alternately spaced magnetic field producing members or ring magnets 59 which are annular in shape and which are alternately spaced by magnetic insulating members 61 for a purpose to be described.
  • Magnets 59 and magnetic insulating members 61 are held tightly together by a pair of end plates 63, 64 which are received in frame 50.
  • a sleeve 65 is wrapped about the outer periphery of the transport roll.
  • Sleeve 65, end plates 63, 64 and magnetic insulating members 61 are made from any suitable nonmagnetic material. Typical materials comprise glass, or any of the nonmagnetic metals, such as, brass, aluminum or copper and mixtures thereof.
  • the ring magnets 59 conveniently comprise permanent magnets which exhibit polarities indicated by letters N and S in FIG. 2 showing north and south poles, respectively.
  • magnetic fields are produced which result in lines of flux passing through sleeve 65 and forming flux concentrations such that brushlike tufts of magnetic toner material are formed in projecting relationship to the peripheral surface in a somewhat undulating pattern due to the flux patterns being formed.
  • To rotate transport roll 57 there is fixed to end plate 64 one end of a shaft 67 connected at the other end thereof to a driving pulley 69 which can be driven from any suitable power source.
  • the developer coating is moved past a corona charging device 73 similar to the corona charging devices previously described at which time a unifonn charge of a polarity opposite to that of the electrostatic latent image is applied to the developer coating. Charging potentials ranging from about 4500 to about 7500 volts are suitable for the development of latent electrostatic images.
  • An insulating block 74 serves to insulate charging device 73 from housing 50.
  • the charging causes the surface of the developer coating to expand or spread slightly from its position prior to charging.
  • a baffle element 75 is positioned adjacent to corona charging device 73 so that there is a smoothened uniform layer of developer coating presented to the latent image to be developed.
  • Wave forming elements 80 At the topmost position in the path of transport roll 57, there is positioned one or more wave forming elements 80 around which development of the latent image takes place as will become more apparent.
  • Wave forming elements desirably have an arcuate shape and are positioned sufficiently close to the transport roll surface such that a charged layer of the developer coating is deflected upwardly into close proximity with the latent image to be developed due to the rotational movement of the roll.
  • wave forming elements 80 are oscillated in a direction transverse to the rotational movement of the transport roll 57 causing an undulation of the developer coating in the vicinity of development.
  • the latent image is completely submerged in a flowing developer material in an undulating pattern resulting in optimum development of the latent image.
  • Wave forming elements 80 are desirably made out of a conductive material so as to serve as an electrode to strengthen the electrostatic fields emanating from the latent image. Hence the solid area development portion of the image is greatly enhanced.
  • each of the elements 80 may comprise ribbon shaped steel which is approximately .250 inches wide and about .030 to about .075 inches thick.
  • the wave forming elements 80 are shaped tubular at their ends where they are received in openings 81 formed in housing 50. To adjust the tension of the wave forming elements, tensioning screws 83 are threadingly received'at one end of these elements.
  • magnetic fields are utilized from a rotatable linear magnet disposed on the interior of transport roll 57 on a concentric axis therewith.
  • Rotatable magnet 85 is supported by ball bearings 87 and driven by any suitable drive as by shaft 89 driven by a pulley 91. It will be appreciated that when magnet 85 is in the vertical position the magnetic fields directed toward field elements 80 are greatest and thus the field elements .are oscillated or vibrated due to pulsing magnetic forces acting upon them.
  • Both the ring magnets and linear magnet 85 may be made from any suitable material, such as, alnico.
  • the surface of trough 51 and the outer surface of transport roll 57 and field elements be coated with a suitable electrically insulating material, as, for example, ethyl cellulose so that the charged toner particles do not stick to these surfaces or become grounded.
  • a suitable electrically insulating material as, for example, ethyl cellulose
  • the transport roll rotates in the same direction as the travel of the xerographic photoreceptor but at 1.5 to about 5 times the photoreceptor speed so that a renewed portion of the roll continually contacts the latent image.
  • the transport roll continually picks up magnetic toner material from the trough which is at a level slightly less than the outside periphery of the roll. Any suitable means may be used for periodically replenishing the trough with a new supply of magnetic toner material as it is consumed. Since all of the magnetic toner material is utilized in the development of the image, there is no problem of insuring proper metering and proportionality between carrier and toner particles as in the prior art development devices.
  • the magnetic forces emanating from the ring magnets draw a sufficient amount of the material to form a developer coating on the periphery which is then reduced to a uniform thickness by knife blade element 71.
  • the topmost portion of the coating is charged by charging device 73 and smoothened by baffle element 75 for development in the vicinity of the wave forming elements 80. Due to the pulsing action of the wave forming elements, an undulating pattern of developer is flowed across the latent image resulting in high quality development. Since wave forming elements 80 are conductive, image fields are strengthened and solid area development is effected as well as the line copy. Also due to the magnetic attraction of the layer of developer material to the transport roll 57, the background deposited on the photoreceptor is minimized. If desired, an electrical bias may be applied to the transport roll to suppress low electrostatic fields in the background areas.
  • Apparatus for developing a latent electrostatic image comprising:
  • a trough for containing a supply of magnetic toner material; magnetic transport means adapted for movement in a path past said supply of magnetic toner material; drive means for moving said magnetic transport means past said supply of magnetic toner material whereby a developer coating of said magnetic toner material is formed on the surface thereof; charging means positioned in the path of said transport means to apply an electrostatic charge on said developer coating of a polarity opposite that of the latent electrostatic image to be developed; deflection means positioned in the path of said transport means at the development zone to deflect at least a portion of the charged developer coating into close proximity with the latent electrostatic image; and means for oscillating said deflection means in a direction transverse to the path of said transport means to effect undulation of the developer coating during development of the latent image.
  • said deflection means comprises at least one elongated member made up'of electrically conductive material coated with an electrically insulating material.
  • said magnetic transport means comprises a plurality of cylindrically shaped magnet members arranged in a longitudinal row and a layer of nonmagnetic material wrapped around the outer periphery thereof.
  • Apparatus according to claim 1 wherein said last mentioned means comprises a rotatable linear magnet member disposed in the interior of said transport means and means for rotating said magnet member.
  • Apparatus according to claim 1 including a doctor blade element and baffle element positioned in the path of said transport means before and after said charging means, respectively, to cause said developer coating to be doctored to a uniform thickness prior to charging and then smoothcned subsequent to charging.
  • an electrostatic copying machine of the type in which a photoreceptor member on which a latent image is formed is moved past a plurality of processing stations including a development station, the improvement comprising transport means at a development station for moving a developer coating including an electroscopic component and a magnetic component into close proximity with a latent image to be developed and means positioned in the development zone for effecting an undulating pattern to the developer coating during development.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Dry Development In Electrophotography (AREA)
  • Magnetic Brush Developing In Electrophotography (AREA)
  • Coating Apparatus (AREA)
  • Developing Agents For Electrophotography (AREA)
US723041A 1968-04-22 1968-04-22 Development apparatus Expired - Lifetime US3552355A (en)

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US72304168A 1968-04-22 1968-04-22

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US (1) US3552355A (pl)
JP (1) JPS5344826B1 (pl)
AT (1) AT300575B (pl)
BE (1) BE730371A (pl)
BR (1) BR6907459D0 (pl)
CH (1) CH499140A (pl)
CS (1) CS161850B2 (pl)
DE (1) DE1913696A1 (pl)
DK (1) DK129880B (pl)
ES (1) ES365439A1 (pl)
FR (1) FR2006640A1 (pl)
GB (1) GB1263566A (pl)
IE (1) IE32786B1 (pl)
IL (1) IL31757A (pl)
LU (1) LU58295A1 (pl)
NO (1) NO128037B (pl)
PL (1) PL79926B1 (pl)
RO (1) RO61947A (pl)
SE (1) SE341530B (pl)
SU (1) SU383338A3 (pl)

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3640247A (en) * 1969-05-29 1972-02-08 Creed & Co Ltd Magnetic powder applicator
DE2313132A1 (de) * 1972-03-16 1973-09-20 Oce Van Der Grinten Nv Elektrofotografisches verfahren
US3866575A (en) * 1971-09-06 1975-02-18 Canon Kk Magnet roll developing device
JPS5015560A (pl) * 1973-06-08 1975-02-19
JPS5045639A (pl) * 1973-08-27 1975-04-23
US3882821A (en) * 1969-03-08 1975-05-13 Canon Kk Developing device for electrophotography
JPS5098333A (pl) * 1973-12-26 1975-08-05
DE2729946A1 (de) * 1976-06-30 1978-01-05 Minnesota Mining & Mfg Elektrographisches entwicklungsverfahren
US4068622A (en) * 1975-10-22 1978-01-17 Oce-Van Der Grinten N.V. Magnetic roller
JPS5316441U (pl) * 1976-07-22 1978-02-10
US4081571A (en) * 1974-08-01 1978-03-28 Mita Industrial Co. Ltd. Method for developing electrostatic latent images
US4086873A (en) * 1974-07-09 1978-05-02 Konishiroku Photo Industry Co., Ltd. Electrophotographic developing device incorporating a developing electrode having an insulation layer on its surface
JPS5358244A (en) * 1976-11-08 1978-05-26 Konishiroku Photo Ind Co Ltd Preparation of electrostatic image developer
US4122209A (en) * 1977-04-18 1978-10-24 E. I. Du Pont De Nemours And Company Magnetic image decorator
US4126100A (en) * 1974-08-01 1978-11-21 Mita Industrial Company Ltd. Apparatus for causing a developer powder to make an irregular motion in a developing zone
US4185130A (en) * 1977-04-18 1980-01-22 E. I. Du Pont De Nemours And Company Magnetic image decorator
JPS5511299A (en) * 1979-07-09 1980-01-26 Konishiroku Photo Ind Co Ltd Image forming method
US4240374A (en) * 1979-05-29 1980-12-23 E. I. Du Pont De Nemours And Company Magnetic image decorator having rotating cylinders and knife blades associated therewith
US4246588A (en) * 1977-10-24 1981-01-20 Compagnie Internationale Pour L'informatique Particle feed arrangement for applying solid particles to the image carrier of a non-impact printer
US4292922A (en) * 1979-02-24 1981-10-06 Konishiroku Photo Industry Co., Ltd. Developing device for an electrophotographic copying machine
US4318607A (en) * 1980-07-14 1982-03-09 Xerox Corporation Magnet for a development system
US4324820A (en) * 1980-07-18 1982-04-13 St. Regis Paper Company Method and apparatus for coating a paper web
EP0060534A1 (de) * 1981-03-13 1982-09-22 International Duplicator Ltd. GmbH. Magnetbürsten-Entwicklungsvorrichtung für elektrostatische Ladungsbilder auf Aufzeichnungsträgern
US4378753A (en) * 1980-05-26 1983-04-05 Konishiroku Photo Industry Co., Ltd. Developing apparatus for an image reproduction
JPS61281251A (ja) * 1986-05-16 1986-12-11 Konishiroku Photo Ind Co Ltd 一成分系絶縁性磁性現像剤および一成分系絶縁性磁性現像剤の帯電方法

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54154332A (en) * 1978-05-25 1979-12-05 Toshiba Corp Smoke layer forming device of magnetic powder
US4292924A (en) * 1979-10-03 1981-10-06 Xerox Corporation Magnetic brush apparatus

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2786439A (en) * 1953-06-30 1957-03-26 Rca Corp Electrophotographic developing apparatus
US2822779A (en) * 1956-09-24 1958-02-11 Century Geophysical Corp Developer for electrostatic photography
US3015305A (en) * 1958-05-23 1962-01-02 Xerox Corp Development of electrostatic images
US3098765A (en) * 1959-03-16 1963-07-23 Robertson Photo Mechanix Inc Xerographic brush
US3203395A (en) * 1963-06-14 1965-08-31 Addressograph Multigraph Apparatus for developing electrostatic images
US3318284A (en) * 1964-01-30 1967-05-09 Hitachi Ltd Apparatus for developing electrostatic images of records
US3358594A (en) * 1966-01-17 1967-12-19 American Can Co Electrostatic printing with a magnetic brush feed
US3392432A (en) * 1963-12-18 1968-07-16 Azoplate Corp Magnetic roller for electro-photographic development
US3429741A (en) * 1965-06-11 1969-02-25 Eastman Kodak Co Method of coating using a bead coater
US3464383A (en) * 1966-01-14 1969-09-02 Wilhelm Knechtel Powder dispensing cylinder for an electrostatic powder fixing device

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2786439A (en) * 1953-06-30 1957-03-26 Rca Corp Electrophotographic developing apparatus
US2822779A (en) * 1956-09-24 1958-02-11 Century Geophysical Corp Developer for electrostatic photography
US3015305A (en) * 1958-05-23 1962-01-02 Xerox Corp Development of electrostatic images
US3098765A (en) * 1959-03-16 1963-07-23 Robertson Photo Mechanix Inc Xerographic brush
US3203395A (en) * 1963-06-14 1965-08-31 Addressograph Multigraph Apparatus for developing electrostatic images
US3392432A (en) * 1963-12-18 1968-07-16 Azoplate Corp Magnetic roller for electro-photographic development
US3318284A (en) * 1964-01-30 1967-05-09 Hitachi Ltd Apparatus for developing electrostatic images of records
US3429741A (en) * 1965-06-11 1969-02-25 Eastman Kodak Co Method of coating using a bead coater
US3464383A (en) * 1966-01-14 1969-09-02 Wilhelm Knechtel Powder dispensing cylinder for an electrostatic powder fixing device
US3358594A (en) * 1966-01-17 1967-12-19 American Can Co Electrostatic printing with a magnetic brush feed

Cited By (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3882821A (en) * 1969-03-08 1975-05-13 Canon Kk Developing device for electrophotography
US3640247A (en) * 1969-05-29 1972-02-08 Creed & Co Ltd Magnetic powder applicator
US3866575A (en) * 1971-09-06 1975-02-18 Canon Kk Magnet roll developing device
DE2313132A1 (de) * 1972-03-16 1973-09-20 Oce Van Der Grinten Nv Elektrofotografisches verfahren
JPS5015560A (pl) * 1973-06-08 1975-02-19
JPS576589B2 (pl) * 1973-06-08 1982-02-05
JPS5045639A (pl) * 1973-08-27 1975-04-23
JPS5098333A (pl) * 1973-12-26 1975-08-05
JPS5738901B2 (pl) * 1973-12-26 1982-08-18
US4086873A (en) * 1974-07-09 1978-05-02 Konishiroku Photo Industry Co., Ltd. Electrophotographic developing device incorporating a developing electrode having an insulation layer on its surface
US4126100A (en) * 1974-08-01 1978-11-21 Mita Industrial Company Ltd. Apparatus for causing a developer powder to make an irregular motion in a developing zone
US4081571A (en) * 1974-08-01 1978-03-28 Mita Industrial Co. Ltd. Method for developing electrostatic latent images
US4068622A (en) * 1975-10-22 1978-01-17 Oce-Van Der Grinten N.V. Magnetic roller
DE2729946A1 (de) * 1976-06-30 1978-01-05 Minnesota Mining & Mfg Elektrographisches entwicklungsverfahren
JPS5316441U (pl) * 1976-07-22 1978-02-10
JPS572996Y2 (pl) * 1976-07-22 1982-01-19
JPS5358244A (en) * 1976-11-08 1978-05-26 Konishiroku Photo Ind Co Ltd Preparation of electrostatic image developer
JPS604459B2 (ja) * 1976-11-08 1985-02-04 コニカ株式会社 静電荷像現像剤の製造方法
US4122209A (en) * 1977-04-18 1978-10-24 E. I. Du Pont De Nemours And Company Magnetic image decorator
US4185130A (en) * 1977-04-18 1980-01-22 E. I. Du Pont De Nemours And Company Magnetic image decorator
US4246588A (en) * 1977-10-24 1981-01-20 Compagnie Internationale Pour L'informatique Particle feed arrangement for applying solid particles to the image carrier of a non-impact printer
US4292922A (en) * 1979-02-24 1981-10-06 Konishiroku Photo Industry Co., Ltd. Developing device for an electrophotographic copying machine
US4240374A (en) * 1979-05-29 1980-12-23 E. I. Du Pont De Nemours And Company Magnetic image decorator having rotating cylinders and knife blades associated therewith
JPS5511299A (en) * 1979-07-09 1980-01-26 Konishiroku Photo Ind Co Ltd Image forming method
US4378753A (en) * 1980-05-26 1983-04-05 Konishiroku Photo Industry Co., Ltd. Developing apparatus for an image reproduction
US4318607A (en) * 1980-07-14 1982-03-09 Xerox Corporation Magnet for a development system
US4324820A (en) * 1980-07-18 1982-04-13 St. Regis Paper Company Method and apparatus for coating a paper web
EP0060534A1 (de) * 1981-03-13 1982-09-22 International Duplicator Ltd. GmbH. Magnetbürsten-Entwicklungsvorrichtung für elektrostatische Ladungsbilder auf Aufzeichnungsträgern
WO1982003280A1 (en) * 1981-03-13 1982-09-30 Brueckel Dieter Magnetic brush developing device for electrostatic charge pictures on recording media
JPS61281251A (ja) * 1986-05-16 1986-12-11 Konishiroku Photo Ind Co Ltd 一成分系絶縁性磁性現像剤および一成分系絶縁性磁性現像剤の帯電方法
JPS6341061B2 (pl) * 1986-05-16 1988-08-15 Konika Kk

Also Published As

Publication number Publication date
NO128037B (pl) 1973-09-17
DK129880B (da) 1974-11-25
GB1263566A (en) 1972-02-09
CS161850B2 (pl) 1975-06-10
JPS5344826B1 (pl) 1978-12-01
IE32786L (en) 1969-10-22
FR2006640A1 (pl) 1970-01-02
ES365439A1 (es) 1971-03-16
CH499140A (de) 1970-11-15
SE341530B (pl) 1971-12-27
AT300575B (de) 1972-07-25
IL31757A0 (en) 1969-05-28
IE32786B1 (en) 1973-11-28
LU58295A1 (pl) 1969-10-28
DE1913696A1 (de) 1969-11-13
IL31757A (en) 1973-01-30
RO61947A (pl) 1977-08-15
SU383338A3 (pl) 1973-05-25
PL79926B1 (pl) 1975-08-30
BR6907459D0 (pt) 1973-01-18
BE730371A (pl) 1969-09-24
DK129880C (pl) 1975-05-12

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