US3003462A - Apparatus for applying developer powder to photo-conductive insulating sheets - Google Patents

Apparatus for applying developer powder to photo-conductive insulating sheets Download PDF

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Publication number
US3003462A
US3003462A US634873A US63487357A US3003462A US 3003462 A US3003462 A US 3003462A US 634873 A US634873 A US 634873A US 63487357 A US63487357 A US 63487357A US 3003462 A US3003462 A US 3003462A
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US
United States
Prior art keywords
developer powder
photo
developer
mixture
applicator roll
Prior art date
Legal status (The legal status 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 status listed.)
Expired - Lifetime
Application number
US634873A
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English (en)
Inventor
Sr Paul B Streich
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bruning Charles Co Inc
Original Assignee
Bruning Charles Co Inc
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 to BE564031D priority Critical patent/BE564031A/xx
Priority to DENDAT1067305D priority patent/DE1067305B/de
Application filed by Bruning Charles Co Inc filed Critical Bruning Charles Co Inc
Priority to US634873A priority patent/US3003462A/en
Priority to GB662/58A priority patent/GB828188A/en
Priority to FR1197882D priority patent/FR1197882A/fr
Priority to CH342587D priority patent/CH342587A/fr
Application granted granted Critical
Publication of US3003462A publication Critical patent/US3003462A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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

Definitions

  • This invention relates to apparatus for developing electrostatically charged latent images and more particularly to processes and apparatus for applying the developer powder or toner to electrostatically charged latent images on photo-conductive insulating sheets prior to the fixing of the developer powder to produce the desired prints.
  • Electrostatic printing techniques comprise producing a uniform electrostatic charge upon the surface of a photo-conductive insulating material, such, for example, as paper coated with a finely-divided photo-conductor, e.g., zinc oxide, applied to the paper base as a solution or suspension in a dielectric film-forming vehicle.
  • the vehicle may be a resin solution or suspension, such as a solution of a silicone resin in a suitable solvent, or a suspension of a polyvinyl acetate resin in an aqueous medium.
  • Further description of the photoconductive insulating material is believed unnecessary because the present invention may be used for applying developer powder to all known photo-conductive insulating materials.
  • the latent image is produced, as is also well known by exposing the charged surface to a light image, thus discharging the portions irradiated by the light rays while leaving the remainder of the surface in a charged condition.
  • the latent image is then developed by applying a developer powder which is held electrostatically to the charged area.
  • This powder is then fixed to the photoconductive surface, for example, by heat in those cases Where the powder is a resin or other material which can be fixed by heat, or by application of a solvent or by other known fixing technique.
  • a developer powder consisting essentially of a mixture of finely-divided magnetic carrier particles, such as finely-divided iron, magnetite or ferrites and developer powder such as the developer powders described, for example, in US. Patents 2,297,691, 2,618,552 and 2,638,416, including dyed or pigmented resin powders, e.g., Vinsol resin (treated pine resin) dyed with suitable dyes, coumarone-indene resins, gum copal, rosin, wax, etc.
  • dyed or pigmented resin powders e.g., Vinsol resin (treated pine resin) dyed with suitable dyes, coumarone-indene resins, gum copal, rosin, wax, etc.
  • the material for the developer powder and the magnetic material are selected in accordance with their triboelectric properties, so that when mixed the developer powder has the desired charge depending on the charge carried by the electrostatically charged latent image.
  • the developer powder should be so chosen that when mixed with the magnetic particles, it is negatively charged.
  • the developer powder should be chosen so that when mixed with the magnetic particles, it carries a positive charge.
  • Developer powder which when mixed with magnetic particles, such as iron, acquire the desired charges by triboelectric action are well known and can be selected from many materials that have been tested and occupy recognized positions in a triboelectric series.
  • pigmented rosin when mixed with iron becomes positively charged and can be used as the developer powder for developing negatively charged images.
  • mixtures containing developer powder and magnetic carrier particles are well known and per se do not form part of the present invention, further description thereof would serve no useful purpose.
  • Apparatus heretofore employed for applying the developer powder to the electrostatically charged latent images on photo-conductive insulating material frequently involve the formation of a cloud of developer powder which settles over the machine. This, of course, is objectionable, because not only does it result in an unpleas ant and unsightly working atmosphere, but also in the production of poor prints caused for example by developer particles from the cloud settling on the background areas.
  • Another object of this invention is to provide such apparatus which result in uniform development of the images and with the production of images having a clear background.
  • FIGURE 1 is a composite view partly in vertical section and partly in elevation and shows the developer powder applicator roll positioned in a trough containing a mixture of magnetic particles and developer powder and also shows a portion of the return feed screw disposed below the trough;
  • FlGURE 2 is a cross-section through the machine taken at right angles to the longitudinal axis of the applicator roll in a plane indicated by line 22 on FIGURE 1;
  • FIGURE 3 is a horizontal sectional view through the feed and return chambers and shows the applicator roll and the feed screws in the return and feed chambers in elevation; this figure, for the sake of clarity of illustration, shows the return or discharge chamber positioned laterally to one side of the applicator roll and not directly beneath the applicator roll as in FIGURES 1 and 2;
  • FlGURE 4 is a fragmentary plan view, showing the developer powder bin and its structural relationship to the applicator roll shown schematically in FIGURE 4;
  • FIGURE 5 is an end elevational view of the developer power bin taken in the directions indicated by arrows 5-5 on FlGURE 4 and illustrates one form of drive for the agitator and the return and feed screws;
  • FlGURE 6 is a vertical section of the developer powder bin taken in a plane indicated by line 66 on FIGURE 4.
  • 10 indicates the frame of the machine on which is suitably fixed the trough 11.
  • the applicator roll 13 Suitably journaled for rotation, as for example, in ball bearings 12 mounted on frame ltl is the applicator roll 13.
  • This roll is constituted of washer or disc-shaped magnets 14 mounted on a shaft 15 and alternating with washer or disc-shaped pole pieces 16 also mounted on shaft 15.
  • the assembly of magnets 14 and pole pieces 16 are held on shaft 15 in face to face contact by nut 17 threaded on threaded end 13 of shaft 15.
  • Each magnet 14 is magnetized throughout its thickness thus having an opposite pole on each face.
  • Ideal magnets which are magnetized throughout their thickness suitable for use in this invention are those manufactured by the Indiana Steel Products Co., Valparaiso, Indiana, and sold under the trade name Lndox 1.
  • the magnets 14 are assembled on shaft 15 with like poles of adjacent magnets facing each other but with the washer shaped ferrous pole pieces 16 separating them.
  • the pole pieces are, therefore, alternately magnetized north and south along the length of the applicator roll.
  • magnetic flux lines are formed extending throughout the periphery of-the'applicator roll 13; these flux lines are indicated at 19. 1
  • Applicator roll 13 has fixed to an extension of shaft 15 a driving sprocket which can be driven from any suitable source of power to rotate this roll with its periphery moving over a body 21 of magnetic particles and developer powder disposed in trough 11.
  • the latter is formed with its upper edge or lip 22 positioned approximately of an inch from the periphery of the applicator roll 13, thus forming a narrow space between the periphery of this roll and the exit end of the trough which controls the thickness of the layer 23 on roll 13.
  • Layer 23 is constituted of a mixture of developer powder and magnetic particles, which mixture is continuously brought up by the applicator roll 13 in its rotation, as clearly shown in FIGURE 2. 7
  • Trough I I is longitudinally elongated as shown in FIG- URE 3 and is provided near its base with anopening 24 disposed approximately midway between the ends of the trough 11.
  • Communicating with this opening 24 is a feed chamber 25 having rotatably mounted in its base a feed screw 26.
  • End 27 of chamber 25 remote from opening 24 communicates with one end of a bin 28.
  • Bin 28 also communicates with a longitudinally extending discharge chamber 29 provided with openings 31 and 32 communicably connecting the discharge chamber 29 with the opposite ends of the trough 11.
  • a feed screw 33 Disposed in the base of 9 the discharge chamber 29 is a feed screw 33 which is mounted for rotation in the base of the discharge chamber and extends the length thereof.
  • Rotation of the feed screws 26 and 29 can be effected, for example, by a chain drive involvinga chain 34 passing over sprockets on the applicator roll shaft and the shaft of feed screw 33 and a second chain 35 passing over sprockets 36 fixed to the shafts of feed screws 33 and 26. It will be understood other suitable drives may be used. 7
  • agitator 38 Mounted for rotation on a shaft 37 in bin 28 is an agitator 38.
  • the agitator is in the form of a rotating hub 39 having radially extending'arms 41.
  • This agitator may be rotated by the drive chain 35 which drives the sprocket 42 fixed to its shaft 37. In its rotation it not only eifects agitation of the developer powder magnetic particles mixture but also elevates the mixture along the upwardly rising wall 43 (FIGURE 5) of bin 28 to deliver the mixture to the feed chamber 26.
  • Feeding of the photo-conductive insulating material 45 is effected by two sets of feed rollers 46 and 47 suitably spaced on opposite sides of the applicator roll 13, and which feed the insulating material 45 into tangential contact with layer 23 on roll 13.
  • These feed rollers may have their peripheries of nap or pile material to provide a soft, firm drive for the insulating material 45.
  • the nap or pile material is of a material in the triboelectric series which is located in this series remote from the position in the series of the material of which the developer powder is constiuted.
  • the nap may be of Orlon, Dacron, Saran fiber, or acetate rayon. If it has a negative charge, it may be of nylon, glass W001, W001 or animal fur.
  • Such feed rolls are more completely described in the copending patent application of John I. Schulze, Serial No. 629,069 (now Patent No. 2,894,744
  • rollers 48 and 49 Mounted for rotation directly above the applicator roll 16 are a pair of spaced polygonal agitating rolls 48 and 49, positioned so that their peripheries engage the back of insulating material 45 as it is fed over the applicator roll 13. While in the embodiment shown in FIG- URE 2 these rollers are shown hexagonal in shape, they may be rectangular or other polygonal shape. These rollers are driven from any suitable drive at a relatively 4 rapid rate, e.g., from 1,000 to 2,000 rpm. to rapidly vibrate or agitate the sheet of insulating material 45 passing face down over the applicator roll [13.
  • the applicator roll 13 is rotated in the direction of the arrows on FIGURE 2.
  • the mixture of developer powder and magnetic particles is fed by feed screw 26 to the opening 24.
  • This mixture is attracted by the magnetic fields at the periphery of the pole pieces and is pulled through the opening 2 4.
  • This action produces the layer 23 of magnetic particles and developer powder mixture on the surface of the roll of even thickness determined by the space between the periphery of the applicator roll 13 and the lip 22 of trough 11.
  • Trough 11 is at ground potential which maintains the natural charge on both the magnetic particles and the developer powder in the layer'23 of this mixture on the applicator roll 13 applied to the photo-conductive insulat ing material 45.
  • the electrostatic charge on the insulating material 45 has a greater attraction for the developer power'than the magnetic particles have and, hence, the developer powder adheres to the image.
  • the developer powder is fixed to produce the desired prints.
  • the applicator roll 13 is driven at the same surface sp ed, as the insulating material 45. This cums nates any tendency to form a cloud of developer powder that would settle over the machine.
  • the agitating rolls 48 and 49 do not come into contact with the developer powder and, hence, do not cause the formation of such objectionable cloud.
  • the present invention is ideally suited for developing sheets or webs of insulating material because the applicator roll 13 and the feed rolls 46 and 47 can be driven at the same surface speed.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Dry Development In Electrophotography (AREA)
US634873A 1957-01-18 1957-01-18 Apparatus for applying developer powder to photo-conductive insulating sheets Expired - Lifetime US3003462A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
BE564031D BE564031A (US06272168-20010807-M00014.png) 1957-01-18
DENDAT1067305D DE1067305B (US06272168-20010807-M00014.png) 1957-01-18
US634873A US3003462A (en) 1957-01-18 1957-01-18 Apparatus for applying developer powder to photo-conductive insulating sheets
GB662/58A GB828188A (en) 1957-01-18 1958-01-07 Process and apparatus for applying developer powder to photo-conductive insulating material
FR1197882D FR1197882A (fr) 1957-01-18 1958-01-14 Procédé et appareil d'application d'une poudre de révélateur à une matière isolante photo-conductrice
CH342587D CH342587A (fr) 1957-01-18 1958-01-16 Procédé de développement d'images latentes chargées électrostatiquement sur une feuille de matière isolante photoconductrice et appareil pour la mise en oeuvre de ce procédé

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US634873A US3003462A (en) 1957-01-18 1957-01-18 Apparatus for applying developer powder to photo-conductive insulating sheets

Publications (1)

Publication Number Publication Date
US3003462A true US3003462A (en) 1961-10-10

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Family Applications (1)

Application Number Title Priority Date Filing Date
US634873A Expired - Lifetime US3003462A (en) 1957-01-18 1957-01-18 Apparatus for applying developer powder to photo-conductive insulating sheets

Country Status (6)

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US (1) US3003462A (US06272168-20010807-M00014.png)
BE (1) BE564031A (US06272168-20010807-M00014.png)
CH (1) CH342587A (US06272168-20010807-M00014.png)
DE (1) DE1067305B (US06272168-20010807-M00014.png)
FR (1) FR1197882A (US06272168-20010807-M00014.png)
GB (1) GB828188A (US06272168-20010807-M00014.png)

Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3081737A (en) * 1961-03-01 1963-03-19 Gen Aniline & Film Corp Xerographic apparatus for applying ferromagnetic powder
US3098765A (en) * 1959-03-16 1963-07-23 Robertson Photo Mechanix Inc Xerographic brush
US3133834A (en) * 1961-06-22 1964-05-19 Rca Corp Electrostatic developing apparatus
US3144354A (en) * 1960-03-10 1964-08-11 Keuffel & Esser Co Electrographic printer
US3145122A (en) * 1962-08-13 1964-08-18 Addressograph Multigraph Apparatus for applying developer powder to photo-conductive insulating material
US3152012A (en) * 1960-12-19 1964-10-06 Ibm Apparatus for the development of electrostatic images
US3152924A (en) * 1961-05-24 1964-10-13 Robertson Photo Mechanix Inc Xerographic brush
US3167455A (en) * 1963-01-31 1965-01-26 Dick Co Ab Developer for facsimile printing machine
US3196831A (en) * 1959-11-16 1965-07-27 American Photocopy Equip Co Developing unit for photocopy machine
US3233586A (en) * 1961-07-27 1966-02-08 Lumoprint Zindler Kg Devices for the application of developer powder
US3246629A (en) * 1963-06-18 1966-04-19 Addressograph Multigraph Apparatus for developing electrostatic images
US3257224A (en) * 1961-12-27 1966-06-21 Azoplate Corp Method and apparatus for developing electrostatic images
US3358594A (en) * 1966-01-17 1967-12-19 American Can Co Electrostatic printing with a magnetic brush feed
US3358637A (en) * 1962-04-24 1967-12-19 Plastic Coating Corp Toner unit for photoelectrostatic reproduction equipment
US3369917A (en) * 1963-09-10 1968-02-20 Daniel B. Granzow Magnetic brush development of electrostatic images utilizing a high voltage corona
US3399652A (en) * 1967-06-14 1968-09-03 Addressograph Multigraph Automatic toner concentrate detector
US3557751A (en) * 1967-05-20 1971-01-26 Minolta Camera Kk Device for dry development in electrophotography
US3566076A (en) * 1969-07-03 1971-02-23 Xerox Corp Toner fixing apparatus
US3633545A (en) * 1969-11-03 1972-01-11 Bell & Howell Co Magnetic printout equipment
US3639051A (en) * 1964-06-30 1972-02-01 Savin Business Machines Corp Electrostatic copier
US3647499A (en) * 1969-08-19 1972-03-07 Eastman Kodak Co Process for transferring dry developed electrographic images
US3687106A (en) * 1969-07-11 1972-08-29 Xerox Corp Donor apparatus and method
US3700142A (en) * 1971-09-20 1972-10-24 Singer Co Powder dispensing unit
US3866575A (en) * 1971-09-06 1975-02-18 Canon Kk Magnet roll developing device
US3877417A (en) * 1973-10-15 1975-04-15 Xerox Corp Transfer corona generating device with support brushes
US3943886A (en) * 1973-12-17 1976-03-16 Oce-Van Der Grinten N.V. Developing apparatus for electrostatic charge images
US3949704A (en) * 1972-05-22 1976-04-13 Xerox Corporation Magnetic brush developing apparatus
US4310611A (en) * 1979-06-29 1982-01-12 Eastman Kodak Company Electrographic magnetic carrier particles
US4656964A (en) * 1982-12-27 1987-04-14 Ricoh Company, Ltd. Developing device
US4887130A (en) * 1985-10-07 1989-12-12 Minolta Camera Kabushiki Kaisha Electrostatic latent image developing apparatus

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2975758A (en) * 1958-03-13 1961-03-21 Haloid Xerox Inc Apparatus for developing electrostatic images
DE1297989B (de) * 1961-03-17 1969-06-19 Rank Xerox Ltd Vorrichtung zum Nachschub von Tonerpulver in das Entwicklerpulver eines elektrofotografischen Kopiergeraetes
NL286305A (US06272168-20010807-M00014.png) * 1961-12-16
NL288124A (US06272168-20010807-M00014.png) * 1962-01-25
DE1196962B (de) * 1962-11-05 1965-07-15 Ece Elektrostatik Magnetwalze zur Entwicklung von elektrostatischen Abbildungen
JPS5759550B2 (US06272168-20010807-M00014.png) * 1973-05-01 1982-12-15 Ricoh Kk
GB2006054B (en) * 1977-09-10 1982-12-08 Canon Kk Developing apparatus for electrostatic image
DE2831805C2 (de) * 1978-07-19 1982-10-28 Siemens AG, 1000 Berlin und 8000 München Vorratsbehälter für pulverförmigen Toner

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US668941A (en) * 1900-04-21 1901-02-26 Guy H Waring Method of magnetically separating ores.
US1114071A (en) * 1913-07-03 1914-10-20 Krupp Ag Grusonwerk Magnetic separator.
US2376922A (en) * 1941-06-04 1945-05-29 Behr Manning Corp Method of and apparatus for making pile fabrics
US2625905A (en) * 1950-04-13 1953-01-20 Rosson Richards Proc Co Inc Apparatus for applying coating material to pipe
US2686733A (en) * 1951-07-17 1954-08-17 Dunlop Tire & Rubber Corp Production of pile fabrics
US2763204A (en) * 1955-05-11 1956-09-18 Sperry Rand Corp Magnetic printer
US2786440A (en) * 1953-06-30 1957-03-26 Rca Corp Electrophotographic developing apparatus
US2786441A (en) * 1953-07-20 1957-03-26 Rca Corp Apparatus for applying electrostatic developer powder by means of a magnetic brush
US2791949A (en) * 1956-02-01 1957-05-14 Haloid Co Xerographic copying device
US2811465A (en) * 1952-04-30 1957-10-29 Rca Corp Electrostatic printing
US2822779A (en) * 1956-09-24 1958-02-11 Century Geophysical Corp Developer for electrostatic photography
US2841461A (en) * 1952-07-26 1958-07-01 Gen Dynamics Corp Apparatus for magnetic printing
US2854947A (en) * 1953-07-01 1958-10-07 Rca Corp Electrostatic printing

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US668941A (en) * 1900-04-21 1901-02-26 Guy H Waring Method of magnetically separating ores.
US1114071A (en) * 1913-07-03 1914-10-20 Krupp Ag Grusonwerk Magnetic separator.
US2376922A (en) * 1941-06-04 1945-05-29 Behr Manning Corp Method of and apparatus for making pile fabrics
US2625905A (en) * 1950-04-13 1953-01-20 Rosson Richards Proc Co Inc Apparatus for applying coating material to pipe
US2686733A (en) * 1951-07-17 1954-08-17 Dunlop Tire & Rubber Corp Production of pile fabrics
US2811465A (en) * 1952-04-30 1957-10-29 Rca Corp Electrostatic printing
US2841461A (en) * 1952-07-26 1958-07-01 Gen Dynamics Corp Apparatus for magnetic printing
US2786440A (en) * 1953-06-30 1957-03-26 Rca Corp Electrophotographic developing apparatus
US2854947A (en) * 1953-07-01 1958-10-07 Rca Corp Electrostatic printing
US2786441A (en) * 1953-07-20 1957-03-26 Rca Corp Apparatus for applying electrostatic developer powder by means of a magnetic brush
US2763204A (en) * 1955-05-11 1956-09-18 Sperry Rand Corp Magnetic printer
US2791949A (en) * 1956-02-01 1957-05-14 Haloid Co Xerographic copying device
US2822779A (en) * 1956-09-24 1958-02-11 Century Geophysical Corp Developer for electrostatic photography

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3098765A (en) * 1959-03-16 1963-07-23 Robertson Photo Mechanix Inc Xerographic brush
US3196831A (en) * 1959-11-16 1965-07-27 American Photocopy Equip Co Developing unit for photocopy machine
US3144354A (en) * 1960-03-10 1964-08-11 Keuffel & Esser Co Electrographic printer
US3152012A (en) * 1960-12-19 1964-10-06 Ibm Apparatus for the development of electrostatic images
US3081737A (en) * 1961-03-01 1963-03-19 Gen Aniline & Film Corp Xerographic apparatus for applying ferromagnetic powder
US3152924A (en) * 1961-05-24 1964-10-13 Robertson Photo Mechanix Inc Xerographic brush
US3133834A (en) * 1961-06-22 1964-05-19 Rca Corp Electrostatic developing apparatus
US3233586A (en) * 1961-07-27 1966-02-08 Lumoprint Zindler Kg Devices for the application of developer powder
US3257224A (en) * 1961-12-27 1966-06-21 Azoplate Corp Method and apparatus for developing electrostatic images
US3358637A (en) * 1962-04-24 1967-12-19 Plastic Coating Corp Toner unit for photoelectrostatic reproduction equipment
US3145122A (en) * 1962-08-13 1964-08-18 Addressograph Multigraph Apparatus for applying developer powder to photo-conductive insulating material
US3167455A (en) * 1963-01-31 1965-01-26 Dick Co Ab Developer for facsimile printing machine
US3246629A (en) * 1963-06-18 1966-04-19 Addressograph Multigraph Apparatus for developing electrostatic images
US3369917A (en) * 1963-09-10 1968-02-20 Daniel B. Granzow Magnetic brush development of electrostatic images utilizing a high voltage corona
US3639051A (en) * 1964-06-30 1972-02-01 Savin Business Machines Corp Electrostatic copier
US3358594A (en) * 1966-01-17 1967-12-19 American Can Co Electrostatic printing with a magnetic brush feed
US3557751A (en) * 1967-05-20 1971-01-26 Minolta Camera Kk Device for dry development in electrophotography
US3631838A (en) * 1967-05-20 1972-01-04 Minolta Camera Kk Device for dry development in electrophotography
US3399652A (en) * 1967-06-14 1968-09-03 Addressograph Multigraph Automatic toner concentrate detector
US3566076A (en) * 1969-07-03 1971-02-23 Xerox Corp Toner fixing apparatus
US3687106A (en) * 1969-07-11 1972-08-29 Xerox Corp Donor apparatus and method
US3647499A (en) * 1969-08-19 1972-03-07 Eastman Kodak Co Process for transferring dry developed electrographic images
US3633545A (en) * 1969-11-03 1972-01-11 Bell & Howell Co Magnetic printout equipment
US3866575A (en) * 1971-09-06 1975-02-18 Canon Kk Magnet roll developing device
US3700142A (en) * 1971-09-20 1972-10-24 Singer Co Powder dispensing unit
US3949704A (en) * 1972-05-22 1976-04-13 Xerox Corporation Magnetic brush developing apparatus
US3877417A (en) * 1973-10-15 1975-04-15 Xerox Corp Transfer corona generating device with support brushes
US3943886A (en) * 1973-12-17 1976-03-16 Oce-Van Der Grinten N.V. Developing apparatus for electrostatic charge images
US4310611A (en) * 1979-06-29 1982-01-12 Eastman Kodak Company Electrographic magnetic carrier particles
US4656964A (en) * 1982-12-27 1987-04-14 Ricoh Company, Ltd. Developing device
US4887130A (en) * 1985-10-07 1989-12-12 Minolta Camera Kabushiki Kaisha Electrostatic latent image developing apparatus
US5044313A (en) * 1985-10-07 1991-09-03 Minolta Camera Kabushiki Kaisha Electrostatic latent image developing apparatus

Also Published As

Publication number Publication date
BE564031A (US06272168-20010807-M00014.png)
GB828188A (en) 1960-02-17
DE1067305B (US06272168-20010807-M00014.png) 1959-10-15
CH342587A (fr) 1959-11-30
FR1197882A (fr) 1959-12-03

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