US3775104A - Electrophotographic process using corona discharge current of an asymmetrical wave form - Google Patents

Electrophotographic process using corona discharge current of an asymmetrical wave form Download PDF

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US3775104A
US3775104A US00212898A US3775104DA US3775104A US 3775104 A US3775104 A US 3775104A US 00212898 A US00212898 A US 00212898A US 3775104D A US3775104D A US 3775104DA US 3775104 A US3775104 A US 3775104A
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Prior art keywords
charge
corona discharge
image
polarity
discharge current
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US00212898A
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English (en)
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S Matsumoto
N Yonaha
T Aizawa
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Kyocera Mita Industrial Co Ltd
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Mita Industrial Co Ltd
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/043—Photoconductive layers characterised by having two or more layers or characterised by their composite structure
    • G03G5/0433—Photoconductive layers characterised by having two or more layers or characterised by their composite structure all layers being inorganic
    • 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
    • G03G15/22—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20
    • G03G15/226—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 where the image is formed on a dielectric layer covering the photoconductive layer
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/043—Photoconductive layers characterised by having two or more layers or characterised by their composite structure
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/14—Inert intermediate or cover layers for charge-receiving layers
    • G03G5/147—Cover layers
    • 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
    • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
    • Y10S430/001—Electric or magnetic imagery, e.g., xerography, electrography, magnetography, etc. Process, composition, or product
    • Y10S430/102—Electrically charging radiation-conductive surface

Definitions

  • ABSTRACT An electrophotographic process comprising the stepsv of (a) applying a first chargeby means of direct current corona discharge to an overcoated photosensitive sheet consisting of a conductive base, a photoconduetive layer and a surface insulating layer; (b) applying a second charge to the so charged sensitive sheet by meansof a corona discharge current of asymmetrical wave form in which the discharge current of a polarity opposite that of the first charge is greater than that of the same polarity and the degree of asymmetry is sufficient to satisfy the specified requirements, and simultaneously exposing the sensitive sheet through or original having an image'pattern of light and shadow: and (c) thereafter exposing the photosensitive sheet to an uniform illumination over the entire surface to form a latent electrostatic image of the light area and alatent electrostatic image of the dark area, which are of opposite polarity to each other.
  • an overcoated photosensitive member e.g., a threelayered overcoated photosensitive member consisting of a conductive base, afphotoconductive layer and a surfacev insulating layer
  • an overcoated photosensitive member e.g., a threelayered overcoated photosensitive member consisting of a conductive base, afphotoconductive layer and a surfacev insulating layer
  • the reversion of the polarity of thecharges of the images of the light and dark areas is very desirable to increase the contrast'of the image formed as well as for solving the soiling of the background .by prevention of the so-called fogging during the development operationjFu'rther, if the polarities of thesurface potential of the two are also reversed, the developing toner particles in adhering to the latent electrostatic image of opposite, polarity during the development operation also receive an electrostatic repulsive force from the latent electrostatic image area of while applying th photosensitive member with adirect i the opposite polarity to result m an effluent accomplishment of the development.
  • an electrophotographic process comprises the steps of applying a first charge by means of a direct current corona 'discharge'of a specific polarity to "either a three-layered overcoated' photosensitive member consisting of a conductive base,'aphotoconductive layer and a surface insulating layer or a fourlayered overcoated photosensitive member consisting of a conductive base, aphotoconductive layer, a sur- .face insulating layer and an intermediateinsulating layer disposed either within the photoconductive layer or between the photoconductive layer and the conduc tive base; applying to the so chargedphotosensitive member a second charge by means of a corona dis charge current of an asymmetrical wave form in which the discharge current of a polarity opposite that of the first charge is greater than that of the same polarity and simultaneously exposing the photosensitive member through an original having an image pattern of light and shadow, the degree of asymmetry of the corona discharge current of an asymmetrical wave form being in this case sufficient
  • FIGS 1,-a to 1-0 are views illustrating the sectional construction of the photosensitive member used in the process of the present invention
  • FIGS. 2 -a to 2-e are views explaining the several steps of the process of the present invention
  • FIGS. 3-a to 3-0 are charts illustrating the changes in the potential of the photosensitive member as a whole, the surface of the insulating layer and at the interface of the insulating layer and the photoconductive layer
  • FIGS. 4-41 and 4-b are respectively a wiring diagram of the normal alternating current corona discharge apparatus and a graph showing the wave form of the symmetric discharge current obtained therefrom; I
  • FIGS. S- a to 8-a and FIGS. S-b to 8-b are wiring diagrams of apparatus for obtaining the asymmetric corona discharge, as used in the present invention, and graphs showing the wave forms of the asymmetric corona discharge currents obtained therefrom;
  • FIG. 9 is a schematic view, of an apparatus for practicing the process of the present invention. 1
  • the overcoated photosensitive member usedin the invention consists "of either three or four layers;
  • photo sensitive material shown in FIG- l-a is-made up of a conductive base 1, atop which is superposed a'photoconductive layer 2 and a surface-insualting layer 3.
  • a conductive base 1 atop which is superposed a'photoconductive layer 2 and a surface-insualting layer 3.
  • the surface of the phobinders such as water glass, resinous binders are useable.
  • the resinuous binders which can be used, include such as a styrene polymer or copolymers thereof, polyvinyl acetate or copolymers thereof, acrylic resins, pol yvinyl acetals or'their copolymers, polyvinyl alcohol, polyolefins or copolymers thereof, alkyd resins, polyester resins, silicone resins, epoxy resins and synthetic rubbers.
  • Suitable binders are disclosed in British Pat. No. 1,020,506. I
  • the photoconductor can be treated with an optional sensitizing dyestuff such as rose be'ngal or methylene blue. Again, the photoconductor may be used after activating with a metal suchas gold or copper. In addition, to improve such properties as the preexposingeffects (light fatigue effect) and the dark retoconductor can be treated with a Lewis acid, fatty acid or metal salts thereof and organic phosphoric acid ester compounds.
  • an optional sensitizing dyestuff such as rose be'ngal or methylene blue.
  • the photoconductor may be used after activating with a metal suchas gold or copper.
  • the dark retoconductor can be treated with a Lewis acid, fatty acid or metal salts thereof and organic phosphoric acid ester compounds.
  • the conductive base which supportsthe photoconductive layer
  • metallic base plates of such as aluminum or copper, as well as metallic vapor deposited or plated resins, conductiveresins, papers applied a hydroscopic salt or a conductive substance, and base plates applied a composition of a metallic powder and I a resin
  • the base plate may be either a flat mediate-insulating layer can be disposed .inside the photoconductive layer or between the photoconductive layer and, the conductive base.
  • the sensitive material may be as shown in FIG. l-b, i.e., an overcoated assembly consisting.
  • FIG. l-c i.e., aovercoated assembly consisting of a conductive base 1, an intermediate insulating layer 3, a photoconductive layer 2 and a surface insulating layer 3.
  • the photoconductive layer is that which is known per se and any may be used as desired.
  • a phtooconductor or a combination of a photoconductor and a binder can be used as the photoconductive layer.
  • the photoconductor are such as inorganic photoconductive includes material materials such as selenium, zinc oxide, cadmium sulfide, zinc cadmium sulfide, cadmium telluride, (DdTe), selenium telluride (SeTe), cadmium selenide (CdSe) and antimony trisulfide (Sb S and such organic photoconductive materials as anthracene, anthraguinone and polyvinyl carbazole.
  • photoconductors can be used per se as the photoconductive layer.
  • selenium or cadmium sulfide can be vapor deposited on a suitable base, or a resin which initself possesses photoconductive properties, e.g., polyvinyl carbazole, can. be applied to a base to form the photoconductive layer.
  • a resin which initself possesses photoconductive properties e.g., polyvinyl carbazole
  • a photoconductor can be first dispersed in a binder and'then this can be applied to a conductive base.
  • a binder in addtion to inorganic plate or one which is cylindrical in shape.
  • the transparent dielectrics having high dielectric strength such, for example, as the films of polyesters, cellulose esters, polystyrene and.
  • FIG. 2-a first charge
  • the surface of the surface insuIat-. ing layer 3 becomes charged up topotential 6 due to a charge of 'a given polarity (e.g., positive).
  • the interface portion between the photoconductive layer 2 and insulating layer 3 becomes charged up to a potential 7 due to a charge of opposite polarity (negative).
  • the photoconductor is a negative type semiconductor in this case, the surface of the I photoconductive layer is ,applied a positive electrostatic charge by applying the electrode with a positive 7 discharge voltage.
  • the surface of the photoconductive layer is applied a negative electrostatic charge by applying the electrode with a negative discharge voltage.
  • voltage ranging between about 5,000 and about 10,000 volts is preferred.
  • the photosensitive member which has been applied the first charge, is applied a charge of a corona discharge current of an asymmetric wave form from a charging apparatus 9 having an electrode 10; at the same time the photosensitive member is exposed to an image pattern of lightand shadow (FIG. 2-5: deemed charge-image exposure).
  • the corona discharge current of an asymmetrical wave form and the exposure are preferably conducted at the same time, it need not be necessarily at the same time in the case whre the change from'the light resistance to the dark resistance of the photoconductor used as the photosensitive layer is not rapid. "Inthis case'the corona discharge current of an asymetrical wave form'may'be applied immediately after the exposure.
  • the charge by means of the corona discharge current of an asymetrical waveform, asherein used, must be onein which the discharge current of a polarity opposite that of the first charge is greater than that of the same polarity and moreover must be one which has a degree of asymmetry sufficient to change the'polarities of the potentials of both the light and shadow portions of the image pattern of the photosensitive member to opposite polarities as well as to form an electrostatic latent image of the dark area v
  • the so preparedsensitive material having electro static latent images in 'which 1 the polarities of the charges of the light image portion and the dark image portion differ from each other can be then developed by methods which per se are known!
  • the photosensitive member As a result ofthis secondcharge and theexposure, at thelight image portion (L) the photoconductive layer 2 becomes conductive'and the charge at the interface of the surface insulating layer 3 and the photoconductive layer 2 is caused to disappear to result 7 inthe potential becoming equalto the potential of the conductive base (ground potential), and at the same time, due to the asymmetric current charge the surface of the insulating layer 3 is charged with a polarity (negative).opposite that of the first.
  • the negative and positive images can be developed by choosing, as required, toners either positively or negatively charged.
  • the toner particles since the background of the image is charged with a polarity opposite that of the latent electrostatic image to be developed, the toner particles receivesimultaneously an attractive force of the staticsurfacelcharge of opposite polarity and a repulsive force of the static surface charge of the same polarity to make it possible to carry" out the development with greater efficiency. As a result, there is no soiling of thebackground.
  • any of the developing procedures can be slightly neutralizedby the corona discharge current of asymmetrical wave form becomes a new potential 6'.
  • thee shadow image portion D of the photoconductive'layer 2 of the photosensitive member also becomes a conductive layer, and the interfacial potential 7 between, the photoconductive layer 2 and the insulating layer 3 becomes equal to the-potential of the conductive base (ground potential). While it is preferred to carry out the uniform illumination over the entiresurface of the photosensitive member in this step, similar results can be obtained by not performing this uniform illumination of the photosensitive member but by allowing the charge of the foregoing interfare to disappear by providing a sufficient period of time before'subrnitting the photosensitive member to the development step which follows, or by carrying out the development in an anbient light.
  • FIG. 3-a shows the surface potential of the photosensitive member as awhole
  • FIG. 3-b and 3-c show respectively the potentials of the insulating layer surfaceand the potential at the interface'of the photoconductive layer and the insulating surface layer.
  • the potential of the photoconductive layer and the surface layerinterface at the shadow image portion (D) decays slightly by means of the dark decay and reaches .b"D.
  • the potential of'the insulating surfacelayer decays as a result of the corona discharge current of asymmetrical wave form' and reaches bD (In this case since the chargeof the insulating surface layer resulting from the first charge is restrained by the charge of the photoconductive layer and the surface layer interface, it remains the same polarity as that of the first charge even after charging with the asymmetric discharge current).
  • the potential of the insulating layer surface does not change, but the potential of the potoconductive layer and the surface layer interface of the dark portion D becomes equal to the ground potential (c"D) due to the light decay, and the surface potential of the photosensitive member as a whole becomes at the light portion (L) a potential cL, which is opposite in polarity to that of the firstcharge, while at the dark portion (D) becomes a potential cD, which is the same polarity as that of the first charge.
  • corona discharge current of the asymmetrical wave form in which the discharge current of a polarity opposite that of the first charge is greater than that of the same polarity is entirely different from the case where 1 a direct current or an alternating current corona discharge is used as the second charge.
  • FIG. 4-a shows a-conventional alternating corona discharge current generating apparatus.
  • the primary'side 14 of the high voltage transformer is connected'to a commercial altemating current source and the two terminals of the secondary side 12 are connected to the electrode 10 and the opposite electrode 13 of the corona generating apparatus 9, an alternating corona discharge current is produced between the electrode 10 and the opposite electrode l3.
  • Thee current wave form of this corona discharge is of normal wave form.
  • the present invention uses a corona discharge which differs from this normal wave form discharge and is as corona discharge current of asymmetrical wave form in which a discharge current of a given polarity is greater than the discharge current of opposite polarity.
  • the wiring-is as shown in FIG. S-a.
  • One terminal of the high voltage transformer is connected to the corona discharge electrode 10 through the intermediary of a rectifier 15 and a resistor 16 connected in parallel, and the other terminal of the transformer'is connected to the opposite electrode 13.
  • the wave form of the corona discharge current obtained by such a wiring becomes one in which, for example the discharge current of the positive side is restrained while that of the negative side is substantially not restrained, i.e., an asymmetric wave fonn.
  • the magnitude of the discharge current of a given polarity can be freely regulated by changing the value of the resistance 16 connected in parallel with the rectifier l5, and the degree of asymmetry of the wave form of the current can be easily regulated by adjusting the value of the resistor.
  • the discharge current of a given polarity can be restrained, as shown in FIG. 6-a, by providing a controlling grid 17 between the corona discharge electrode 10 and the opposite electrode 13 applying the controlling grid with a direct current voltage from a direct current source 18.
  • thewave form of the'current of the corona discharge becomes asymmetric,'as shown in FIG.
  • an shield 9 which upper side is optically opened disposed in proximity to the discharge electrode 10 can be connected to a direct current voltage source 19, and by applying this shield with a direct current voltage the corona discharge of a given polarity can be restrained, with the consequence that an alternating current corona discharge. current having an asymmetric wave form, as shown in FIG. 7-b, can be obtained.
  • one terminal of the sec? ondary side 12 of the high voltage transformer can be grounded through the intermediary of a direct current voltage source 20, while the other terminal of the transformer is connected to the corona discharge electrode 10 and the opposite elelctrode 13 is grounded.
  • FIG. 8-b is obtained.
  • the drum surface 3 receives either a positiveor. negative direct current corona discharge from a corona discharge apparatus having a discharge electrode 5 connected to a direct current source (a).
  • the drum surface is ex-' posed to an image pattern by means of the exposing device 8 disposed next to the electrode 5 and-at the same time receives a corona discharge current of asymmetrical wave fonn from a-corona discharge apparatus 9 having adischarge electrode 10 connected to corona discharge currentsource of asymmetrical wave form.
  • This latent electrostatic image is developedby means of a magnetic brush 23 disposed inside of a developing device 22 with a toner 6 t'which has been charged with a charge opposite that of the latent electrostatic image whose development is desired.
  • a transfer sheet'24 is fed to between .aroll 25 and the sensitive drum and pressed against the drum surface by means of roll 25, and the transfer of the toner image take place at this point.
  • the transfer sheet 24 to which has beentransferred the toner image is conveyed to a fixing device 26 where the toner image is fixed.
  • the photosensitive drum is removed of its charge by means of a corona discharge device having a discharge electrode 28connected to an alternating current source C and cleaned at a cleaning apparatus 29 equipped with a toner removing brush 30, after which the reproduction operation is repeated.
  • EXAMPLE 1 4 l0 grams of an acrylic resin are added to 90 grams of foregoing sensitive plate is then applied a corona discharge of +7KV to positively charge the Lumilar surface uniformly.
  • a 450-watt tungsten lamp is placed at a pointone meter from the sensitive plate, and the surface of the plate is exposed through an optical system to anoptical image for about one second.
  • corona discharge current of asymmetrical wave fonn is applied to .form a latent electrostatic image in the Lumilar surface.
  • the asymmetric corona discharge current of asymmetrical wave form is obtained in the case using agenerating apparatus wired as shown in FIG.
  • the corona discharge elec-' trode with an alternating current voltage of 8,000 volts and the open shield with 500 volts, while regulating the ratio of negative corona discharge to the positive corona discharge to a ratio of 3:1.
  • the plate is brought into an ambient light and developed with a positively charged toner, and as a result a good quality negative reproduction image without fogging and of small edge effect is obtained. Further, when a latent electrostatic I image produced in similar manner is developed with a negatively'charged toner, a good positive reproduction image is likewise obtained.
  • CONTROL I A sensitive plate prepared by the procedure describedin Example 1 is applied a +7,000V corona dis-' charge, audits Lumilar surface is positively charged. Next, a 300-W tungsten lamp is placed at a point one meter from this sensitive plate, and the surface of the plateis exposed for about one second to an optical image throughan optical system. Simultaneously with this exposure to'the optical image a normal alternating current corona discharge is applied to the plate and a plate, and the plate is exposed for about one second to copper-activated cadmium sulfide followed by the additiori of a small quantity of a solvent.and thorough 1 forming a photoconductive coating on the paper. Next,
  • a Lumilar (A polyethylene terephthalate film) film of about l2-micron thickness is superposed to the foregoing photoconductive coating surface with a binder to thus obtain a sensitive plate.
  • the Lumilar surface ofthe CONTROLL i The sensitive plate of Examplel is applied a +7,000V corona discharge, and the Lumilarsurface is positively charged uniformly.
  • a 450-W, tungsten lamp is placed at a point one meter from this sensitive an optical image through an optical system. Simulta neously with this exposure to the optical image a -7KV direct current corona dischargeis applied and a latent electrostatic image is formed in the Lumilar surface.
  • the plate is then brought out to an ambient light and developed with a negatively charged toner, and as a result a'positive reproduction image having an intense edge effect and of a poor quality usually characteristic of repulsion development is obtained.
  • a foggy negative reproduction image is obtained.
  • An electrophotographic a. applying a first charge by means of direct current corona discharge of a specific polarity to an overcoated photosensitive member selected from the group consisting of a three-layered overcoated sen sitive member consisting of a conductive base, a
  • electrostatic images being of opposite polarity to b. applying to the so charged sensitive member a seceach other ond char e b means of a corona dischar e current v g y g 2.
  • a seceach other ond char e b means of a corona dischar e current v g y g 2.
  • the corona voltage of asymmetrical wave form, said corona discharge being one in which the ratio of the discharge cup of said corona discharge current of asymmetrical wave form is 5,000 10,000 volts.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Electrophotography Using Other Than Carlson'S Method (AREA)
  • Photoreceptors In Electrophotography (AREA)
  • Control Or Security For Electrophotography (AREA)
US00212898A 1970-12-29 1971-12-28 Electrophotographic process using corona discharge current of an asymmetrical wave form Expired - Lifetime US3775104A (en)

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JP45121544A JPS495466B1 (enrdf_load_stackoverflow) 1970-12-29 1970-12-29

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JP (1) JPS495466B1 (enrdf_load_stackoverflow)
DE (1) DE2165360A1 (enrdf_load_stackoverflow)
FR (1) FR2121091A5 (enrdf_load_stackoverflow)
GB (1) GB1361688A (enrdf_load_stackoverflow)
IT (1) IT944495B (enrdf_load_stackoverflow)

Cited By (20)

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US3930850A (en) * 1972-07-31 1976-01-06 Mita Industrial Company, Ltd. Process for electrophotographic copying by transfer of electrostatic images
US3942080A (en) * 1974-04-05 1976-03-02 Scott Paper Company Method and apparatus for applying a uniform electrostatic charge to electrophotographic film
US3956524A (en) * 1974-12-04 1976-05-11 Xerox Corporation Method for the preparation of electrostatographic photoreceptors
US3970546A (en) * 1974-06-04 1976-07-20 Carpco, Inc. Method and apparatus for separating non-ferrous metal from waste material
US3980475A (en) * 1972-07-27 1976-09-14 La Cellophane Process of transferring an electrostatic latent image to a dielectric support
US3992204A (en) * 1973-08-06 1976-11-16 Minnesota Mining And Manufacturing Company Method and medium for producing electrostatic charge patterns
US4052206A (en) * 1974-11-07 1977-10-04 Hitachi, Ltd. Electrophotography
US4063945A (en) * 1977-02-17 1977-12-20 Xerox Corporation Electrostatographic imaging method
US4086650A (en) * 1975-07-14 1978-04-25 Xerox Corporation Corona charging device
US4096543A (en) * 1975-10-25 1978-06-20 Mita Industrial Company, Ltd. Corona discharge device with grid grounded via non-linear bias element
US4106933A (en) * 1975-06-18 1978-08-15 Minnesota Mining And Manufacturing Company Piezoelectric method and medium for producing electrostatic charge patterns
US4136942A (en) * 1975-11-25 1979-01-30 Canon Kabushiki Kaisha Electrophotographic apparatus
US4179290A (en) * 1977-03-14 1979-12-18 Fuji Photo Film Co., Ltd. Photoelectrophoretic photography process involving dual corona treatments of opposite polarity
US4268161A (en) * 1977-02-09 1981-05-19 Canon Kabushiki Kaisha Electrophotographic apparatus with corona discharge control
US4271451A (en) * 1976-07-20 1981-06-02 Hercules Incorporated Method and apparatus for controlling static charges
US4410616A (en) * 1982-05-10 1983-10-18 Xerox Corporation Multi-layered ambipolar photoresponsive devices for electrophotography
US4526848A (en) * 1982-11-27 1985-07-02 Olympus Optical Company Ltd. Electrophotographic process with a.c. charger producing greater positive charge
US4565436A (en) * 1982-11-27 1986-01-21 Olympus Optical Co., Ltd. Electrophotographic copying process
US5162189A (en) * 1989-12-27 1992-11-10 Eastman Kodak Company Toner image pressure transfer method and toner useful therefor
US20050048379A1 (en) * 2003-07-31 2005-03-03 Roderick Koehle Method for checking periodic structures on lithography masks

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JPS5522788B2 (enrdf_load_stackoverflow) * 1973-05-15 1980-06-19
JPS51126875U (enrdf_load_stackoverflow) * 1975-04-09 1976-10-14
JPS5276036A (en) * 1975-12-22 1977-06-25 Canon Inc Method for image formation

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US3438706A (en) * 1966-10-07 1969-04-15 Canon Kk Electrophotographic device
US3655369A (en) * 1967-09-05 1972-04-11 Katsuragawa Denki Kk Persistent internal polarization process in electrophotography
US3609031A (en) * 1968-11-05 1971-09-28 Katsuragawa Denki Kk Method of forming electrostatic latent images
US3677751A (en) * 1968-11-30 1972-07-18 Ricoh Kk Polarity reversal electrophotography

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3980475A (en) * 1972-07-27 1976-09-14 La Cellophane Process of transferring an electrostatic latent image to a dielectric support
US3930850A (en) * 1972-07-31 1976-01-06 Mita Industrial Company, Ltd. Process for electrophotographic copying by transfer of electrostatic images
US3992204A (en) * 1973-08-06 1976-11-16 Minnesota Mining And Manufacturing Company Method and medium for producing electrostatic charge patterns
US3942080A (en) * 1974-04-05 1976-03-02 Scott Paper Company Method and apparatus for applying a uniform electrostatic charge to electrophotographic film
US3970546A (en) * 1974-06-04 1976-07-20 Carpco, Inc. Method and apparatus for separating non-ferrous metal from waste material
US4052206A (en) * 1974-11-07 1977-10-04 Hitachi, Ltd. Electrophotography
US3956524A (en) * 1974-12-04 1976-05-11 Xerox Corporation Method for the preparation of electrostatographic photoreceptors
US4106933A (en) * 1975-06-18 1978-08-15 Minnesota Mining And Manufacturing Company Piezoelectric method and medium for producing electrostatic charge patterns
US4086650A (en) * 1975-07-14 1978-04-25 Xerox Corporation Corona charging device
US4096543A (en) * 1975-10-25 1978-06-20 Mita Industrial Company, Ltd. Corona discharge device with grid grounded via non-linear bias element
US4136942A (en) * 1975-11-25 1979-01-30 Canon Kabushiki Kaisha Electrophotographic apparatus
US4271451A (en) * 1976-07-20 1981-06-02 Hercules Incorporated Method and apparatus for controlling static charges
US4268161A (en) * 1977-02-09 1981-05-19 Canon Kabushiki Kaisha Electrophotographic apparatus with corona discharge control
US4063945A (en) * 1977-02-17 1977-12-20 Xerox Corporation Electrostatographic imaging method
US4179290A (en) * 1977-03-14 1979-12-18 Fuji Photo Film Co., Ltd. Photoelectrophoretic photography process involving dual corona treatments of opposite polarity
US4410616A (en) * 1982-05-10 1983-10-18 Xerox Corporation Multi-layered ambipolar photoresponsive devices for electrophotography
US4526848A (en) * 1982-11-27 1985-07-02 Olympus Optical Company Ltd. Electrophotographic process with a.c. charger producing greater positive charge
US4565436A (en) * 1982-11-27 1986-01-21 Olympus Optical Co., Ltd. Electrophotographic copying process
US5162189A (en) * 1989-12-27 1992-11-10 Eastman Kodak Company Toner image pressure transfer method and toner useful therefor
US20050048379A1 (en) * 2003-07-31 2005-03-03 Roderick Koehle Method for checking periodic structures on lithography masks
US7424144B2 (en) * 2003-07-31 2008-09-09 Infineon Technologies Ag Method for checking periodic structures on lithography masks

Also Published As

Publication number Publication date
JPS495466B1 (enrdf_load_stackoverflow) 1974-02-07
DE2165360A1 (de) 1972-07-27
GB1361688A (en) 1974-07-30
IT944495B (it) 1973-04-20
DE2165360B2 (enrdf_load_stackoverflow) 1975-04-03
FR2121091A5 (enrdf_load_stackoverflow) 1972-08-18

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