US3306193A - Electrostatic screen printing with magnetic conveyer and moving base electrode - Google Patents
Electrostatic screen printing with magnetic conveyer and moving base electrode Download PDFInfo
- Publication number
- US3306193A US3306193A US396060A US39606064A US3306193A US 3306193 A US3306193 A US 3306193A US 396060 A US396060 A US 396060A US 39606064 A US39606064 A US 39606064A US 3306193 A US3306193 A US 3306193A
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- United States
- Prior art keywords
- screen
- particles
- toner
- base electrode
- toner particles
- 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.)
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
- B41M1/00—Inking and printing with a printer's forme
- B41M1/12—Stencil printing; Silk-screen printing
- B41M1/125—Stencil printing; Silk-screen printing using a field of force, e.g. an electrostatic field, or an electric current
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41F—PRINTING MACHINES OR PRESSES
- B41F15/00—Screen printers
- B41F15/08—Machines
-
- 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
- G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S101/00—Printing
- Y10S101/37—Printing employing electrostatic force
Definitions
- This invention relates to electrostatic screen printing are more particularly to a new and novel printing machine for use in high speed electrostatic screen printing processes.
- a stencil-supporting, electrically conductive screen is located near and parallel to a co-extensive sheet electrode,
- the screen and electrode may be either planar or curved into some simple shape, such as a portion of a cylinder or a cone.
- An object to be printed is located between the screen and sheet electrode. These must be sufficiently separated and appropriately shaped to acco-mmodate inclusion of the object therebetween.
- a high voltage, direct current power supply is connected between the screen and sheet electrode to establish and maintain an intense electric field therebetween.
- the screen and sheet electrode essentially constitute the plates of a parallel-plate capacitor.
- the ink used in this previously known printing process is a finely-divided powder.
- This powder is made of a pigmented or dyed substance which generally is a good electrical insulator, has a low melting7 temperature, and is known as toner.
- the toner is applied to the side of the screen opposite to that facing the object to be printed.
- This application of toner to the scr-een may be done with a roller similar to the type used for painting.
- the toner is then accelerated by the electric field between the screen and sheet electrode, and is moved toward the sheet electrode until intercepted by the object being printed. After a suiiicient amount of toner has 'been deposited, the flow is interrupted.
- the object may be then removed from its location between the screen and sheet electrode and may be exposed to heat oran appropriate solvent so as to produce permanent image adhesion to the object.
- the invention to be disclosed hereinafter exhibits some similarity to the prior art just described. They are both stencilling processes, the stencils are preferably electrically conductive and are generally supported on conductive screens, bot-h processes can use the same toner particles, which toner particles are electrically charged for both pr-ocesses, intense electric fields are used to transport toner through space to result in printing, they are both suited to the same printing tasks, and the toner may be permanently affixed to the object or substrate being printed 'by identical methods.
- the previously described method uses the conductive screen which supports the stencil for two functions: (l) charging the toner and (2) establishing and maintaining the electric vfield which carries the toner to the object to be printed.
- the invention to be hereinafter described provides toner charging prior to passage of toner through the screen and without contact of toner with the screen; separating the functions permits control of each independently of the other.
- the invention to be hereinafter disclosed is characterized by: (l) speed; (2) uniformity over extended areas; (3) good control of print density; (4) high resolution with large object-stencil separation; and (5) improved capability of printing upon insulating materials.
- the apparatus hereinafter described exhibits superior advantages in make-ready and clean-up time.
- Another object of this invention is to provide a new and novel apparatus for electrostatic printing upon a substrate, the apparatus comprising a housing, a base electrode disposed adjacent to a portion of the housing, a stencil screen disposed between the substrate and the base electrode, supply means in the housing for supplying toner particles to the Abase electrode, and transfer means for transferring the toner particles from the base electrode to the substrate.
- Another object of this invention is to provide new and novel apparatus, of the type described above, wherein the transfer means comprises means for establishing an electric field between the base electrode and the stencil screen to cause toner particles to be accelerated toward the stencil screen.
- Another object of this invention is to provide new and novel apparatus, of the type described above, wherein the supply means comprises a depository in the housing, and magnetic means for transferring t-he toner particles from the depository to the base electrode.
- Another object of this invention is to provide appalriatus, of the type set forth above, wherein the base electrode comprises an endless conductive belt, the supply means comprising a depository in the housing, and magnetic means for transferring the toner particles from the depository to the endless conductive belt.
- Another object of this invention iis to provide apparatus, of the type described above, wherein the housing has a portion thereof defining an Kinclined plane, the inclined plane having apertures formed therein, ,a toner reservoir disposed in communication with the apertures, and means for transporting toner particles from the toner reservoir through the apertures.
- Another object of this invention is to provide new and novel apparatus for electrostatic printing upon a substr-ate, the apparatus comprising ⁇ a base electrode, a
- stencil screen disposed between the substrate and the base electrode, means for establishing an electric ield between the stencil screen and the base electrode, means for establishing ran electric eld between the substrate and the stencil screen, and control grid means for controlling the electric eld between the substrate and the stencil screen.
- Another object of this invention is to provide, in ian electrostatic printing apparatus, a housing having a portion thereof being disposed to form an inclined plane, the inclined plane having apertures formed therein, a toner reservoir disposed in communication with the apertures, and means for transporting toner particles from the toner reservoir through the apertures.
- Another object of this invention is to provide new and novel apparatus, of the type described above, wherein the Aapertures are provided by a mesh screen, and the means for transporting toner particles from the toner reservoir comprises a rotatable roller disposed in the toner reservoir adjacent to the mesh screen.
- Another object of this invention is to provide, in an apparatus of the type utilizing a mixture of carrier particles and toner particles, a housing, a portion of the housing being disposed to form an inclined plane, the inclined plane having apertures formed therein, the apertures bein-g smaller than the carrier particles and larger than the toner particles, means for cascading carrier particles down the inclined plane past the apertures, and means for forcing toner particles through the apertures and into contact with the carrier particles.
- Another object of the present invention is to provide apparatus for transporting and distributing magnetic particles, the apparatus comprising a housing, a portion of the housing defining a depository for the magnetic particles, a magnetic drum rotatably mounted in the housin-g adjacent to the depository, an endless belt mounted adjacent the magnetic drum and having a magnetic roller separated from the magnetic dimm by a portion of the belt, the magnetic roller having a Imore intense magnetic field than the magnetic drum whereby magnetic particles picked ⁇ up from the depository by the magnetic drum are transferred therefrom to the endless belt.
- Another object of this invention is to provide, in an electrostatic apparatus utilizing carrier particles and toner particles, a base electrode, means for depositing carrier particles and toner particles onto the base electrode, a cleaning electrode, means for transporting the carrier par ticles 'and the toner particles from the base electrode to the cleaning electrode, and means for causing the toner particles to adhere to the cleaning electrode and the carrier particles to be expelled from the cleaning electrode.
- a further object of this invention is to provide apparatus ot the type described above wherein the means for depositing the carrier particles land toner particles on the base electrode comprises a lmagnetic drum and a magnetic lroller, the magnetic roller having a more intense maignetic field than the magnetic drum, the base electrode comprising an endless belt, the belt having a portion thereof disposed between the magnetic drum and the magnetic roller, whereby the carrier particles and the toner particles are attracted from the magnetic drum toward the magnetic roller and deposited .upon the endless belt.
- a still further object of this invention is to provide, in apparatus as described above, an inclined plane which extends downwardly from the endless belt toward the magnetic drum, whereby particles cascading down the inclined plane are directed toward the magnetic drum and attracted by its magnetic tield.
- FIGURE la is a diagriammatical illustration of a developer particle, of the type vused in electrostatic printing, and shows a plurality of small toner particles adhering to a larger carrier particle.
- FIGURE lb is a diagrammatical illustration of fundamental apparatus ior performing an electrostatic screen printing operation
- land shows a developer particle disposed upon a base electrode in spaced relation to a conductive stencil screen which is disposed in parallel relation to the base electrode and is connected in an clectrical circuit therewith such that an electric held may be produced therebetween.
- FIGURE 1c is a diagrammatical illustration ol the printing apparatus upon closing of the switch to establish an electric field, and illustrates a developer particle being expelled from the base electrode and attracted toward the stencil screen.
- FIGURE ld is a diagrammatical view of the printing apparatus and illustrates the carrier particle as being stopped by the stencil screen w .ile smaller toner particles are carried by their momenta through apertures in the stencil screen.
- FIGURE le discloses a substrate being disposed in the path of the toner particles, and also illustrates the carrier particle as being expelled from the stencil screen and attracted toward the base electrode.
- FIGURE lf is a diagrammatical illustration of the printing apparatus and shows the toner particles, which have passed through the stencil screen, as adhering to the substrate, and also shows the carrier particle on a return flight from the base electrode toward the stencil screen.
- FIGURE 2 is a diagrammatical view of a printing machine embodied in the present invention.
- FIGURE 3 is a diagrammatical view of a printing machine embodied in the present invention and illustrates apparatus for and one manner of cleaning the apparatus subsequent to a printing operation.
- FIGURE la discloses a developer particle, generally indicated by the numeral 10, and includes a large carrier particle Il and a plurality of relatively small toner particles 12 which adhere to the carrier particle It by triboelectric forces.
- the carrier particle Il may be formed of electrically conductive material, such as charcoal, or metal shot of steel, aluminum, copper, etc.; however, in addition to being electrically conductive, it is preferred that the carrier particle 11 be formed of a ferromagnetic material such as iron filings.
- the toner particles I2 are preferably formed of a non-conductive material located in a triboelectric series such that the toner particles have a negative charge relative to the carrier particles ill, but the toner particles could also be charged positively with respect to the carrier particles.
- carrier particles Il were comprised of iron filings, to mesh (approximately 4 mils to 6 mils in diameter) supplied by Anken Film and Chemical Company for use in Electrofax magnetic brush developing systems.
- Toner particles used in the present invention are preferably, but not limited thereto, pigmented resin particles which are formed of n-butyl methacrylate (41%) and polystyrene (59%).
- Such toner particles are supplied by Xerox Corporation tor use in electrostatic olIice copiers and have an average particle diameter of I7 microns.
- FIGURE 1b illustrates a single developer particle 10 as being disposed upon a base electrode 15 which is formed of conductive material.
- a stencil screen i6 which is comprised of a wire mesh 17 having a conventional type ot coating 18 to define apertures 19 arranged in a predetermined pattern.
- Gne commercially available screen which is useful in the present invention is a 200 x 200 mesh stainless steel screen woven of 1.6 mil wire. Stencils conventionally used in silk-screen printing, have also been used.
- the base electrode 15 and the stencil screen 16 are connected by suitable conductors to opposite sides-of a suitable high voltage source 22 and a suitable switch 23 is provided in one of the conductors. It is preferred, as shown, that the stencil screen 16 be connected to the positive side of the high voltage source 22, while the base electrode 15 is connected to the negative side of the high voltage source 22. The polarities may be reversed from those shown; however, the polarities shown are preferred for reasons which will become apparent from subsequent description. If the toner is positively charged with respect to the carrier, the stencil screen 16 is preferably connected to the negative side of the high voltage source 22.
- FIGURE lc closing of the switch 23 establishes an intense electric eld between the base electrode 15 and the stencil screen 16, and the developer particle has acquired a net charge from the base electrode and is expelled from the base electrode 15 and is forced by the electric field toward the stencil screen 16.
- the net charging of the developer particle 10 occurs by direct electrical contact between the conductive carrier particle 11 and the base electrode 15.
- the conductive carrier particle 11 acquires the same charge as the conductive base electrode 15 and is, therefore, repelled therefrom.
- FIGURE ld illustrates a sequence of events which occurs at the time that the developer particle 10 is in contact with the conductive stencil screen 16.
- the developer particle 10 acquires a velocity such that upon collision of the carrier particle 11 with the stencil screen 16, toner particles 12 which are in alignment with an aperture 19 continue through the stencil screen 16 and rise thereabove.
- the carrier particle 11 is too large to pass through the small apertures in the stencil screen 16 and, because of contact with the conductive stencil screen 16, the carrier particle 11 acquires a charge at the screen which is opposite to the previous charge upon the carrier particle 11 and, therefore, is repelled by the stencil screen 16 and attracted toward the base electrode 15.
- An electric field may also be established between the stencil screen 16 and the substrate 25 by providingy a base electrode or control grid, such as the grid 41 which is shown in FIGURE 2, adjacent to the substrate on the side thereof which is remote from the stencil screen 16.
- a base electrode or control grid is held at the same polarity but at a higher potential than the stencil screen 16. As a result, such an electric field aids in propelling the toner particles toward the substrate 25.
- FIGURES le and lf each illustrates a substrate 25 as being disposed above the stencil screen 16.
- the developer particles 1l continue to oscillate back and forth between the base electrode 15 and the stencil screen 16 until sufiicient toner has been acquired upon the substrate 25 to produce a print of the desired optical density.
- the substrate 25 and the pattern thereon, which is formed by the toner particles 12 being deposited in a pattern which is determined by the apertures 19, are exposed to heat or vapors of a suitable solvent such that the toner particles are fused to the substrate 25.
- FIGURE 2 Illustrated in FIGURE 2 is a basic printing machine, generally indicated by the numeral 28, which printing machine embodies the present invention.
- the printing machine 28 includes a housing 29 which is formed of a non-magnetic material, such as plastic, wood, or any other suitable material.
- An endless conductive ybelt 3f) is disposed adjacent to the top of the housing 29, and performs the functions as described above with reference to the base such as carbon tissue,
- the housing 29 also includes a portion thereof defining an inclined plane 31 which provides a path for cascading developer particles 10 and/ or carrier particles 11 downwardly toward a portion of the housing 29 which defines a depository, generally indicated by the numeral 32.
- a magnetic drum 33 is disposed adjacent to the depository 32 and may be mounted upon a shaft 34 and rotated by suitable drive means (not shown) in a counterclockwise direction as is indicated by the arrow in FIGURE 2.
- One operative embodiment of the present invention included a magnetic drum 33 which was comprised of an aluminum drum about 12 inches in diameter, which drum was covered by wrapping the entire curved surface with butting pieces of a flexible magnetic tape one inch wide and 1A@ inch thick, No. 60,208, purchased from the American Science Center of Chicago, Illinois. This was then wrapped with Mylar film, having a thickness of about 40 mils, so as to reduce the field intensity.
- the conductive belt electrode 30 is suitably mounted upon a pair of rollers 36 and 37, either one or both of which are driven by suitable drive means (not shown).
- the roller 36 is a magnetic roller and is disposed adjacent to the magnetic drum 33 and separated therefrom by a portion of the conductive belt electrode 30.
- the magnetic roller 36 is designed so as to have a more intense magnetic eld associated therewith than the magnetic field which is associated with the magnetic drum 3'3. Consequently, developer particles 1f) or carrier particles 11, which ⁇ are picked up at the depository 32 by the magnetic drum 33, are transported by the magnetic drum to the conductive belt electrode 3f) and, because of the more intense magnetic field of the magnetic roller 36, the developer particles 1li or carrier particles 11 are transferred to the surface of the conductive belt electrode 30.
- the electrode 3f As the electrode 3f moves, it carries the particles away from the roller 36 and to a doctor blade 38 where the distribution and flow may be controlled.
- An overflow-turbe (not shown) returns excess particles from the doctoring zone back to the depository 32.
- An electrical connection is generally, though not necessarily, made to the conductive belt electrode 30 by lgoing through the doctor blade 38 and developer particles 10.
- the developer particles 10 are transported into the printing zone where the oscillations of the particles between the electrode 30 and the stencil screen 16 occur, as were previously described in FIGURES lar-lf.
- Toner particles 12 which pass through the stencil apertures 19 are electrically transported to the substrate 25 being printed.
- the electric field which does this is located between the screen 16 and the substrate 25.
- Corona wires 46 are provided for producing the desired corona discharge and an electric field is established be tween the stencil screen 16 and a control grid 41 to cause some of the ions formed by the corona discharge to be carried to the substrate 25. This establishes a high intensity electric field between the substrate 25 and the screen 16.
- the charge deposited on the substrate 25 tends to 'neutralize the field associated with a charged toner ima-ge which is caused by the accumulation of toner particles 12 upon the substrate 25.
- accumulation of toner particles 12 on the substrate 25 has little influence on subsequently arriving toner particles.
- an electrical connection made directly to it can accomplish both functions.
- a co-extensive electrode behind it can accomplish both.
- no corona discharges and no control grids are required.
- insulating materials such as cellulose acetate, the use of the corona discharge is preferred.
- ions deposited on one side and toner particles, carrying charge of the opposite 7 polarity, deposited on the other side of the substrate tends to form a double charge layer with only a small net external electric field.
- conduction neutralizes the ions but also produces an excess or deficiency of electrons at the surface on which the toner particles are deposited, so that a similar result occurs.
- the carrier particles 11 cascade down the inclined plane 31 which returns them to the depository 32.
- toner particles 1?. are added to replace those depleted by the printing operation.
- a toner reservoir 45 which is provided with a pivotally mounted cover 46.
- a cylindrical brush 47 such as a paint roller, which brush is rotatably driven by suitable means (not shown).
- the brush 47 feeds toner particles from the reservoir 45 through apertures 48 in the inclined plane 31.
- the inclined plane 31 consist, at that portion adjacent the roller 47, of a piece of 200 mesh stainless steel wire cloth.
- the apertures 48 in this screen are large enough to pass toner particles 12 but are small enough to block passage of carrier particles 11 which are cascading down the inclined plane 31. While a brush 47 has been disclosed as the preferred means for forcing toner particles through the apertures 48, it is to be understood that other suitable means may be substituted for the brush 47, such as a gentle ow of air.
- toner particles are forced through the screen apertures 48.
- the toner particles are mixed with and adhere to the carrier particles.
- Subsequent cascading down the inclined plane 31 tends to improve mixing of the particles and contact between the carrier particles 11 and the toner particles 12 produces the triboelectric forces necessary for the toner particles 12 to adhere to the carrier particles 11.
- obstacles such as deflecting plates, can be located on the inclined plane 31 to further enhance mixing.
- the carrier particles 11 are returned to the depository 32 with substantially the same amount of toner particles as when they left.
- the roller 47 is rotated at such a speed as to supply toner particles 12 in an amount substantially equal to the amount of toner particles being used for printing upon the substrate 25.
- the printing machine 28 may be provided with any suitable source of power.
- a suitable power source was comprised of a Sorensen 230%2 P. R. & D. high voltage DC. power supply, with an output variable from to 30 kilovolts.
- a potentiad difference of approximately 12 kilovolts was maintained between the stencil screen 16 and the conductive belt electrode 30, with the screen being positive relative to the electrode 3f). It is preferable that the stencil screen 16 be cleaned between each printing operation and, for such cleaning operation, a voltage of 12 kilovolts, or slightly less, was maintained with the screen being negative relative to the base electrode 30.
- high voltage sources 50, 51, 52 and 53 are provided.
- the high voltage source 52 maintains a potential difference of approximately 12 kilovolts between the base electrode 30 and the stencil screen 16, as set forth above.
- the voltage source 50 may be varied Ibetween 50() to 1000 volts for maintaining the control grid 41 at such potential difference above the stencil screen 16 while the corona electrodes 40, which are comprised of two and three mil platinum wires, have been operated about kilovolts above the control grid 41 by high voltage source 51.
- the stencil Cit screen 16 has been spaced approximately 1/2 inch above the conductive belt electrode 30, the control grid 41 has been spaced approximately 1/2 inch above the stencil screen 16, and the corona electrodes 4l) have been spaced approximately 1/2 inch above the control grid 41.
- the control grid 41 is preferably comprised of a 16 x 16 mesh bronze screen woven of wire about 23 mils in diameter.
- the purpose of this control grid 41 is to control the flow of ions formed by the corona discharge, at the corona electrodes 40, such that some of the ions formed in this discharge are carried to the substrate 25.
- suitable switches 55, 56 and 57 may be provided for simultaneously opening and closin gthe circuitry containing the high voltage sources Si), 51 and 52.
- Such switch-es 55, 55 and 57 may be connected together by a suitable mechanical connection which is illustrated by the dotted line 53.
- a high voltage source 53 may be supplied between each printing operation.
- the high voltage source 53 can establish a potential difference between the conductive base electrode 30 and the stencil screen 16 of l2 kilovolts, or slightly less, and is, therefore, comparable to the high voltage source 52 except that a normally opened pushbutton 59 places the high voltage source 53 into the circuit such that the polarities of the conductive belt electrode 30 and stencil screen 16 are reversed.
- the stencil screen 16 is maintained at the same polarity as the triboelectrically charged toner particles. In the cited example, this would be negative.
- the field intensity between the screen 16, and the belt 3f is suiciently high that the developer particles oscillate vigorously between the screen and belt similarly to their motion during printing.
- the electric field is oppositely directed to that used for printing.
- the carrier particles mechanically dislodge accumulated toner from the screen when they strike it during the oscillations. Once dislodged, the electric field carries the toner away from the screen. Some toner can be removed with only .a high intensity electric Afield of appropriate direction. However, this has not been found adequate for repetitive printing. supplementing the field with the oscillating carrier particles, though, has been found to be completely adequate.
- a high density print can be obtained if continued for a sufficient time, such as several minutes.
- the times actually used for cleaning typically are from 0.1 second to 0.4 second.
- FIGURE 3 Illustrated in FIGURE 3 is a feature of the present invention wherein the carrier particles 11 can be used to clean the printing machine 28 at the end of a printing task.
- a continuous electrode 60 having a continuous conductive surface 61, may be substituted for the stencil screen 16 and can be used to remove toner particles from the carrier particles 11. This is done by maintaining the cleaning electrode 60, by the high voltage source 62, at substantially the same potential as the stencil screen 16 when printing is occurring.
- the electric field between the cleaning electrode 60 and the conductive belt electrode 30 causes the carrier particles to oscillate back-andforth between them.
- Astoner particles are freed by carrier collisions, they are attracted to the cleaning electrode 60. In this manner, toner particles may be removed from the carrier particles in substantial quantities.
- the collected toner particles can be continuously removed from the cleaning electrode 60, by a suitable scraper 63, and deposited in a toner recovery bin 64.
- Cleaned carrier particles 11 are recirculated through the printing machine 28 and will pick up any toner particles that may have collected on surfaces in the printing machine itself.
- This cleaning and recirculating operation for approximately several minutes, substantially all cleaning required to change toner colors can be automatically and expeditiously accomplished.
- the brush 47 is maintained at rest so as not to add additional toner particles to the system.
- Apparatus for electrostatic printing upon a substrate comprising a housing, a base electrode disposed adjacent to a portion of said housing, a stencil screen disposed between said substrate and said ba-se electrode, supply means in said housing for supplying conductive carrier particles and toner particles to said base electrode, means for moving said base electrode with said carrier particles and toner particles relative to said stencil screen and said housing, and transfer means for transferring said toner particles from said base electrode to said substrate; said supply means comprising a depository in said housing, and magnetic means for transferring said conductive carrier particles and toner particles from said depository to said base electrode.
- Apparatus for electrostatic printing upon a substrate comprising a housing, a base electrode disposed adjacent to a portion of said housing, a stencil screen disposed between said substrate and said base electrode, supply means in said housing for supplying toner particles to said base electrode, and transfer means for transferring said toner particles from said base electrode to said substrate; said base electrode comprising an endless conductive belt; said supply means comprising a depository in said housing, magnetic means for transferring said toner particles from said depository to said endless conductive belt.
- Apparatus for electrostatic printing upon a substrate comprising a housing, a base electrode disposed adjacent to a portion of said housing, a stencil screen disposed between said substrate and said base electrode, supply means in said housing for supplying toner particles to said base electrode, and transfer means for transferring said toner particles from said base electrode to said substrate; said housing having a portion thereof defining an inclined plane, said inclined plane having apertures formed therein, a toner reservoir disposed in communication with said apertures at an undersurface of said inclined plane, and means for transporting toner particles from said toner reservoir through said apertures.
- Apparatus for electrostatic printing upon a substrate comprising a base electrode, a conductive stencil screen disposed in spaced relation between said substrate and said base electrode, means for establishing a first electric field between said stencil screen and said base electrode, means for establishing a second electric field between said substrate and said stencil screen, and control grid means for controlling said second electric field between said substrate and said stencil screen.
- Apparatus for electrostatic printing upon a substrate comprising a base electrode, a stencil screen disposed between said substrate and said base electrode, means for establishing an electric eld between said stencil screen and said base electrode, said means comprising a high voltage energy source, conductor means connecting one side of said source to said stencil screen, a conductive doctor blade means for distributing toner particles on said base electrode and being disposed in electrical contact with said base electrode, and conductor means connecting the other side of said source to said conductive doctor blade.
- a housing a portion of said housing being disposed to form an inclined plane having an upper end and a lower end, said inclined plane having apertures formed therein along a portion thereof intermediate said upper and lower ends, a toner reservoir disposed in communication with said apertures at an undersurface of said inclined plane and means for transporting toner particles from said toner reservoir through said apertures.
- said means for transporting toner particles from said toner reservoir comprises a rotatable roller disposed in said toner reservoir subadjacent to said mesh screen.
- a housing a portion of said housing being disposed to form an inclined plane, said inclined plane having apertures formed therein, said apertures being smaller than said carrier particles and larger than said toner particles, means for cascading carrier particles down said inclined plane past said apertures, and means for forcing toner particles through said apertures and into contact with said carrier particles.
- Apparatus for transporting and distributing magnetic particles comprising a housing, a portion of said housing defining a depository for said magnetic particles, a magnetic drum rotatably mounted in said housing adjacent to said depository, and endless belt mounted adjacent said magnetic drum and having a magnetic roller separated from said magnetic drum by a portion of said belt, said magnetic roller having a more intense magnetic field than said magnetic drum whereby magnetic particles picked up from said depository by said magnetic drum are transferred therefrom to said endless belt.
- said inclined plane is provided with a plurality of apertures which are smaller in size than said magnetic particles, a toner reservoir for toner particles of a size smaller than said apertures, said toner reservoir being disposed in communication with said apertures and having means for forcing toner particles through said apertures and into contact with said magnetic particles as said magnetic particles cascade down said inclined plane.
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Printing Methods (AREA)
- Printers Or Recording Devices Using Electromagnetic And Radiation Means (AREA)
- Electrostatic Charge, Transfer And Separation In Electrography (AREA)
Priority Applications (13)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US396060A US3306193A (en) | 1964-09-14 | 1964-09-14 | Electrostatic screen printing with magnetic conveyer and moving base electrode |
DE1546739A DE1546739C3 (de) | 1964-09-14 | 1965-07-15 | Vorrichtung zum elektrostatischen Bedrucken einer Unterlage |
GB30921/65A GB1120051A (en) | 1964-09-14 | 1965-07-21 | Improvements in printing |
GB9104/68A GB1120052A (en) | 1964-09-14 | 1965-07-21 | Improvements in printing |
FR28173A FR1458313A (fr) | 1964-09-14 | 1965-08-12 | Impression par pochoir électrostatique |
SE10982/65A SE319782B (xx) | 1964-09-14 | 1965-08-23 | |
SE17217/67A SE359060B (xx) | 1964-09-14 | 1965-08-23 | |
CH1723967A CH473685A (fr) | 1964-09-14 | 1965-09-10 | Appareil à écran-stencil pour l'impression électrostatique |
CH1276565A CH449671A (fr) | 1964-09-14 | 1965-09-10 | Appareil pour l'impression électrostatique sur un support |
CH1723867A CH465407A (fr) | 1964-09-14 | 1965-09-10 | Procédé pour l'impression électrostatique sur un support et appareil pour la mise en oeuvre de ce procédé |
BE669583D BE669583A (xx) | 1964-09-14 | 1965-09-14 | |
NL656511977A NL151030B (nl) | 1964-09-14 | 1965-09-14 | Inrichting voor het elektrostatisch zeefdrukken. |
DK469565AA DK126248B (da) | 1964-09-14 | 1965-09-14 | Fremgangsmåde og apparat til elektrostatisk at påføre et grundlag et selektivt overtræk. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US396060A US3306193A (en) | 1964-09-14 | 1964-09-14 | Electrostatic screen printing with magnetic conveyer and moving base electrode |
Publications (1)
Publication Number | Publication Date |
---|---|
US3306193A true US3306193A (en) | 1967-02-28 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US396060A Expired - Lifetime US3306193A (en) | 1964-09-14 | 1964-09-14 | Electrostatic screen printing with magnetic conveyer and moving base electrode |
Country Status (8)
Country | Link |
---|---|
US (1) | US3306193A (xx) |
BE (1) | BE669583A (xx) |
CH (2) | CH449671A (xx) |
DE (1) | DE1546739C3 (xx) |
DK (1) | DK126248B (xx) |
GB (2) | GB1120051A (xx) |
NL (1) | NL151030B (xx) |
SE (2) | SE319782B (xx) |
Cited By (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3357403A (en) * | 1967-01-03 | 1967-12-12 | Xerox Corp | Powder cloud development apparatus |
US3357349A (en) * | 1967-02-10 | 1967-12-12 | Owens Illinois Inc | Reciprocating power bed with plural replenishing means for electrostatic printer |
US3358594A (en) * | 1966-01-17 | 1967-12-19 | American Can Co | Electrostatic printing with a magnetic brush feed |
US3372675A (en) * | 1966-08-01 | 1968-03-12 | Friden Inc | Electrostatic image processor |
US3396700A (en) * | 1967-08-09 | 1968-08-13 | Xerox Corp | Xerographic toner dispensing apparatus |
US3402659A (en) * | 1966-08-29 | 1968-09-24 | Owens Illinois Inc | Electrical printing processes employing two fields of different strengths |
US3413917A (en) * | 1966-11-16 | 1968-12-03 | Purex Corp Ltd | Electrostatic printing with means to change polarity of counter electrode |
US3428025A (en) * | 1966-12-27 | 1969-02-18 | Xerox Corp | Xerographic development apparatus |
US3448687A (en) * | 1965-05-06 | 1969-06-10 | Monsanto Co | Ink delivery method for electrostatic printing |
US3460468A (en) * | 1965-02-24 | 1969-08-12 | Owens Illinois Inc | Electrical printing methods and apparatus for decorating cylindrical articles |
US3470009A (en) * | 1964-12-28 | 1969-09-30 | Xerox Corp | Powder cloud development of electrostatic images |
US3542579A (en) * | 1964-12-28 | 1970-11-24 | Xerox Corp | Electrostatic image development |
US3561356A (en) * | 1967-02-24 | 1971-02-09 | Continental Can Co | Precharging of substrate for electrostatic printing |
US3599604A (en) * | 1968-01-11 | 1971-08-17 | Xerox Corp | Xerographic development apparatus |
US3610205A (en) * | 1968-10-17 | 1971-10-05 | Continental Can Co | Apparatus for measuring and controlling mixture content |
US3623123A (en) * | 1969-03-10 | 1971-11-23 | Singer Co | Electrostatic printer |
US3635157A (en) * | 1968-12-30 | 1972-01-18 | Continental Can Co | Method and apparatus for electrostatically charging particles for printing or coating |
US3643311A (en) * | 1969-12-11 | 1972-02-22 | Ece Gmbh | Rotatable powder dispensing cylinder for an electrostatic powder image fixing apparatus |
US3731146A (en) * | 1970-12-23 | 1973-05-01 | Ibm | Toner distribution process |
US3776132A (en) * | 1971-02-01 | 1973-12-04 | Continental Can Co | Falling developer curtain printing and coating |
US3793985A (en) * | 1966-07-25 | 1974-02-26 | Xerox Corp | Imaging system |
US3906121A (en) * | 1971-05-25 | 1975-09-16 | Xerox Corp | Electrostatic development method using magnetic brush configuration transport |
US3914460A (en) * | 1973-01-09 | 1975-10-21 | Xerox Corp | Development utilizing electric fields |
US4004508A (en) * | 1971-01-25 | 1977-01-25 | Continental Can Company, Inc. | Magnetic stirring apparatus for developer mixtures |
US4041901A (en) * | 1969-01-14 | 1977-08-16 | Continental Can Co., Inc. | Apparatus for electrostatic printing or coating and developer mix circulating system |
US4100611A (en) * | 1976-05-11 | 1978-07-11 | Xerox Corporation | Apparatus for controlling airborne particle emission |
US4351604A (en) * | 1979-04-26 | 1982-09-28 | Ricoh Company, Ltd. | Multi-color electrostatic copying apparatus |
US4550068A (en) * | 1984-01-30 | 1985-10-29 | Markem Corporation | Vertical magnetic brush developing apparatus and method |
US20040247357A1 (en) * | 2003-03-27 | 2004-12-09 | Frauens Michael W. | Method and system for wide format toning |
US20050202164A1 (en) * | 2004-03-09 | 2005-09-15 | Eastman Kodak Company | Powder coating apparatus and method of powder coating using an electromagnetic brush |
US20060150902A1 (en) * | 2004-03-09 | 2006-07-13 | Eastman Kodak Company | Powder coating apparatus and method of powder coating using an electromagnetic brush |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102007027473A1 (de) | 2007-06-14 | 2008-12-18 | Manroland Ag | Drucktechnisch hergestellte funktionale Komponenten |
Citations (23)
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US2576047A (en) * | 1948-10-21 | 1951-11-20 | Battelle Development Corp | Method and apparatus for printing electrically |
US2626865A (en) * | 1951-05-08 | 1953-01-27 | Haloid Co | Portable electrophotographic powder-image transfer mechanism |
US2758524A (en) * | 1953-12-30 | 1956-08-14 | Rca Corp | Electrostatic photographic printing |
US2787556A (en) * | 1955-11-23 | 1957-04-02 | Sylvania Electric Prod | Image reproduction device screen forming process |
US2846333A (en) * | 1955-11-01 | 1958-08-05 | Haloid Xerox Inc | Method of developing electrostatic images |
US2895847A (en) * | 1953-12-21 | 1959-07-21 | Battelle Development Corp | Electric image development |
US2904000A (en) * | 1957-05-15 | 1959-09-15 | Century Geophysical Corp | Magnetic-brush developer |
US2940864A (en) * | 1954-03-24 | 1960-06-14 | Sylvania Electric Prod | Method of preparing a fluorescent screen |
US3052564A (en) * | 1954-12-20 | 1962-09-04 | Ibm | Printing with magnetic ink |
US3074086A (en) * | 1959-02-04 | 1963-01-22 | Tribune Company | Apparatus for removing dust from paper webs |
US3079483A (en) * | 1962-01-02 | 1963-02-26 | Xerox Corp | Xerographic fixing apparatus |
US3081737A (en) * | 1961-03-01 | 1963-03-19 | Gen Aniline & Film Corp | Xerographic apparatus for applying ferromagnetic powder |
US3081698A (en) * | 1960-03-04 | 1963-03-19 | Electrostatic Printing Corp | Electrostatic printing system |
US3099856A (en) * | 1961-12-28 | 1963-08-06 | Xerox Corp | Web cleaner apparatus |
US3100426A (en) * | 1960-04-26 | 1963-08-13 | Edward K Kaprelian | Electrophotographic printers |
US3124457A (en) * | 1962-04-02 | 1964-03-10 | Charge | |
US3149356A (en) * | 1962-11-01 | 1964-09-22 | Xerox Corp | Xerographic plate cleaning apparatus |
US3149931A (en) * | 1962-09-04 | 1964-09-22 | Xerox Corp | Xerographic vapor fusing apparatus |
US3176652A (en) * | 1960-09-26 | 1965-04-06 | Xerox Corp | Xerographic developing apparatus |
US3190264A (en) * | 1958-11-28 | 1965-06-22 | Xerox Corp | Xerographic developing apparatus |
US3202093A (en) * | 1963-02-11 | 1965-08-24 | Electrostatic Printing Corp | Electrostatic printing |
US3202092A (en) * | 1963-02-01 | 1965-08-24 | Electrostatic Printing Corp | Electrostatic printing system |
US3218967A (en) * | 1962-12-20 | 1965-11-23 | Electrostatic Printing Corp | Selective printing using electrostatic techniques |
-
1964
- 1964-09-14 US US396060A patent/US3306193A/en not_active Expired - Lifetime
-
1965
- 1965-07-15 DE DE1546739A patent/DE1546739C3/de not_active Expired
- 1965-07-21 GB GB30921/65A patent/GB1120051A/en not_active Expired
- 1965-07-21 GB GB9104/68A patent/GB1120052A/en not_active Expired
- 1965-08-23 SE SE10982/65A patent/SE319782B/xx unknown
- 1965-08-23 SE SE17217/67A patent/SE359060B/xx unknown
- 1965-09-10 CH CH1276565A patent/CH449671A/fr unknown
- 1965-09-10 CH CH1723867A patent/CH465407A/fr unknown
- 1965-09-14 NL NL656511977A patent/NL151030B/xx not_active IP Right Cessation
- 1965-09-14 DK DK469565AA patent/DK126248B/da unknown
- 1965-09-14 BE BE669583D patent/BE669583A/xx unknown
Patent Citations (23)
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US2576047A (en) * | 1948-10-21 | 1951-11-20 | Battelle Development Corp | Method and apparatus for printing electrically |
US2626865A (en) * | 1951-05-08 | 1953-01-27 | Haloid Co | Portable electrophotographic powder-image transfer mechanism |
US2895847A (en) * | 1953-12-21 | 1959-07-21 | Battelle Development Corp | Electric image development |
US2758524A (en) * | 1953-12-30 | 1956-08-14 | Rca Corp | Electrostatic photographic printing |
US2940864A (en) * | 1954-03-24 | 1960-06-14 | Sylvania Electric Prod | Method of preparing a fluorescent screen |
US3052564A (en) * | 1954-12-20 | 1962-09-04 | Ibm | Printing with magnetic ink |
US2846333A (en) * | 1955-11-01 | 1958-08-05 | Haloid Xerox Inc | Method of developing electrostatic images |
US2787556A (en) * | 1955-11-23 | 1957-04-02 | Sylvania Electric Prod | Image reproduction device screen forming process |
US2904000A (en) * | 1957-05-15 | 1959-09-15 | Century Geophysical Corp | Magnetic-brush developer |
US3190264A (en) * | 1958-11-28 | 1965-06-22 | Xerox Corp | Xerographic developing apparatus |
US3074086A (en) * | 1959-02-04 | 1963-01-22 | Tribune Company | Apparatus for removing dust from paper webs |
US3081698A (en) * | 1960-03-04 | 1963-03-19 | Electrostatic Printing Corp | Electrostatic printing system |
US3100426A (en) * | 1960-04-26 | 1963-08-13 | Edward K Kaprelian | Electrophotographic printers |
US3176652A (en) * | 1960-09-26 | 1965-04-06 | Xerox Corp | Xerographic developing apparatus |
US3081737A (en) * | 1961-03-01 | 1963-03-19 | Gen Aniline & Film Corp | Xerographic apparatus for applying ferromagnetic powder |
US3099856A (en) * | 1961-12-28 | 1963-08-06 | Xerox Corp | Web cleaner apparatus |
US3079483A (en) * | 1962-01-02 | 1963-02-26 | Xerox Corp | Xerographic fixing apparatus |
US3124457A (en) * | 1962-04-02 | 1964-03-10 | Charge | |
US3149931A (en) * | 1962-09-04 | 1964-09-22 | Xerox Corp | Xerographic vapor fusing apparatus |
US3149356A (en) * | 1962-11-01 | 1964-09-22 | Xerox Corp | Xerographic plate cleaning apparatus |
US3218967A (en) * | 1962-12-20 | 1965-11-23 | Electrostatic Printing Corp | Selective printing using electrostatic techniques |
US3202092A (en) * | 1963-02-01 | 1965-08-24 | Electrostatic Printing Corp | Electrostatic printing system |
US3202093A (en) * | 1963-02-11 | 1965-08-24 | Electrostatic Printing Corp | Electrostatic printing |
Cited By (35)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3470009A (en) * | 1964-12-28 | 1969-09-30 | Xerox Corp | Powder cloud development of electrostatic images |
US3542579A (en) * | 1964-12-28 | 1970-11-24 | Xerox Corp | Electrostatic image development |
US3460468A (en) * | 1965-02-24 | 1969-08-12 | Owens Illinois Inc | Electrical printing methods and apparatus for decorating cylindrical articles |
US3448687A (en) * | 1965-05-06 | 1969-06-10 | Monsanto Co | Ink delivery method for electrostatic printing |
US3358594A (en) * | 1966-01-17 | 1967-12-19 | American Can Co | Electrostatic printing with a magnetic brush feed |
US3793985A (en) * | 1966-07-25 | 1974-02-26 | Xerox Corp | Imaging system |
US3372675A (en) * | 1966-08-01 | 1968-03-12 | Friden Inc | Electrostatic image processor |
US3402659A (en) * | 1966-08-29 | 1968-09-24 | Owens Illinois Inc | Electrical printing processes employing two fields of different strengths |
US3413917A (en) * | 1966-11-16 | 1968-12-03 | Purex Corp Ltd | Electrostatic printing with means to change polarity of counter electrode |
US3428025A (en) * | 1966-12-27 | 1969-02-18 | Xerox Corp | Xerographic development apparatus |
US3357403A (en) * | 1967-01-03 | 1967-12-12 | Xerox Corp | Powder cloud development apparatus |
US3357349A (en) * | 1967-02-10 | 1967-12-12 | Owens Illinois Inc | Reciprocating power bed with plural replenishing means for electrostatic printer |
US3561356A (en) * | 1967-02-24 | 1971-02-09 | Continental Can Co | Precharging of substrate for electrostatic printing |
US3396700A (en) * | 1967-08-09 | 1968-08-13 | Xerox Corp | Xerographic toner dispensing apparatus |
US3599604A (en) * | 1968-01-11 | 1971-08-17 | Xerox Corp | Xerographic development apparatus |
US3610205A (en) * | 1968-10-17 | 1971-10-05 | Continental Can Co | Apparatus for measuring and controlling mixture content |
US3635157A (en) * | 1968-12-30 | 1972-01-18 | Continental Can Co | Method and apparatus for electrostatically charging particles for printing or coating |
US4041901A (en) * | 1969-01-14 | 1977-08-16 | Continental Can Co., Inc. | Apparatus for electrostatic printing or coating and developer mix circulating system |
US3623123A (en) * | 1969-03-10 | 1971-11-23 | Singer Co | Electrostatic printer |
US3643311A (en) * | 1969-12-11 | 1972-02-22 | Ece Gmbh | Rotatable powder dispensing cylinder for an electrostatic powder image fixing apparatus |
US3731146A (en) * | 1970-12-23 | 1973-05-01 | Ibm | Toner distribution process |
US4004508A (en) * | 1971-01-25 | 1977-01-25 | Continental Can Company, Inc. | Magnetic stirring apparatus for developer mixtures |
US3776132A (en) * | 1971-02-01 | 1973-12-04 | Continental Can Co | Falling developer curtain printing and coating |
US3906121A (en) * | 1971-05-25 | 1975-09-16 | Xerox Corp | Electrostatic development method using magnetic brush configuration transport |
US3914460A (en) * | 1973-01-09 | 1975-10-21 | Xerox Corp | Development utilizing electric fields |
US4100611A (en) * | 1976-05-11 | 1978-07-11 | Xerox Corporation | Apparatus for controlling airborne particle emission |
US4351604A (en) * | 1979-04-26 | 1982-09-28 | Ricoh Company, Ltd. | Multi-color electrostatic copying apparatus |
US4550068A (en) * | 1984-01-30 | 1985-10-29 | Markem Corporation | Vertical magnetic brush developing apparatus and method |
US20040247357A1 (en) * | 2003-03-27 | 2004-12-09 | Frauens Michael W. | Method and system for wide format toning |
US20090052914A1 (en) * | 2003-03-27 | 2009-02-26 | Frauens Michael W | Method and system for wide format toning |
US7706706B2 (en) | 2003-03-27 | 2010-04-27 | Eastman Kodak Company | Method and system for wide format toning |
US20050202164A1 (en) * | 2004-03-09 | 2005-09-15 | Eastman Kodak Company | Powder coating apparatus and method of powder coating using an electromagnetic brush |
US20060150902A1 (en) * | 2004-03-09 | 2006-07-13 | Eastman Kodak Company | Powder coating apparatus and method of powder coating using an electromagnetic brush |
US20080241415A1 (en) * | 2004-03-09 | 2008-10-02 | Stelter Eric C | Powder coating apparatus and method of powder coating using an electromagnetic brush |
US7481884B2 (en) | 2004-03-09 | 2009-01-27 | Eastman Kodak Company | Powder coating apparatus and method of powder coating using an electromagnetic brush |
Also Published As
Publication number | Publication date |
---|---|
DE1546739C3 (de) | 1974-08-22 |
DE1546739B2 (de) | 1974-01-24 |
SE359060B (xx) | 1973-08-20 |
CH465407A (fr) | 1968-11-15 |
DK126248B (da) | 1973-06-25 |
GB1120051A (en) | 1968-07-17 |
NL6511977A (xx) | 1966-03-15 |
BE669583A (xx) | 1965-12-31 |
CH449671A (fr) | 1968-01-15 |
GB1120052A (en) | 1968-07-17 |
DE1546739A1 (de) | 1970-10-15 |
NL151030B (nl) | 1976-10-15 |
SE319782B (xx) | 1970-01-26 |
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