US3169062A - Electrophotographic reproduction process - Google Patents

Electrophotographic reproduction process Download PDF

Info

Publication number
US3169062A
US3169062A US181433A US18143362A US3169062A US 3169062 A US3169062 A US 3169062A US 181433 A US181433 A US 181433A US 18143362 A US18143362 A US 18143362A US 3169062 A US3169062 A US 3169062A
Authority
US
United States
Prior art keywords
layer
image
coating
latent
weight
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
US181433A
Inventor
Klupfel Kurt Walter
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.)
Azoplate Corp
Original Assignee
Azoplate Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from DEK42644A external-priority patent/DE1206307B/en
Priority claimed from DEK43273A external-priority patent/DE1220253B/en
Application filed by Azoplate Corp filed Critical Azoplate Corp
Application granted granted Critical
Publication of US3169062A publication Critical patent/US3169062A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03GELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G13/00Electrographic processes using a charge pattern
    • G03G13/04Exposing, i.e. imagewise exposure by optically projecting the original image on a photoconductive recording material
    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03GELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G13/00Electrographic processes using a charge pattern
    • G03G13/14Transferring a pattern to a second base
    • G03G13/18Transferring a pattern to a second base of a charge pattern
    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03GELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02Charge-receiving layers
    • G03G5/04Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/08Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being inorganic
    • G03G5/087Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being inorganic and being incorporated in an organic bonding material
    • YGENERAL 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
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S430/00Radiation imagery chemistry: process, composition, or product thereof
    • Y10S430/001Electric or magnetic imagery, e.g., xerography, electrography, magnetography, etc. Process, composition, or product
    • Y10S430/102Electrically charging radiation-conductive surface

Definitions

  • the present invention relates to an electrophotographic reproduction process in which a latent resistance image is produced by imagewise exposure of a photoelectrically conductive but non-electrostatically charged insulator layer consisting of or containing inorganic photoserniconductors, a, photoelectrically conductive but nonelectrostatically charged insulator layer on a supporting material is placed on this latent resistance image, the whole is electrostatically charged from the supporting material side and the latent electrostatic image produced on the photoelectrically conductive coating of the superposed supporting material is made visible by known methods of electrophotography and may then be fixed, whereupon a mirror image of the latent resistance image is formed.
  • the photoconductive coatings for the production of latent images are inorganic photoconductive substances, e.g., the oxides, sulfides, selenides, tellurides and iodides molybdenum, lead, antimony and cadchloride, ethylene glycol monomethyl ether or other organic solvents in which they will disperse readily, or in 3,i59,%2 Patented Feb. 9, 1965 mixtures of such solvents.
  • the supporting material is coated with these dispersions in the normal manner, by immersion, painting, roller application or by spraying. The material is then heated to remove the liquid components.
  • the inorganic photoelectrically conductive compounds are applied to the supporting material, with or without the resins, in known manner, e.g., by painting, roller application, immersion or spraying.
  • the coating is then dried, whereupon an even, photoelectrically conductive coating is formed.
  • Supports primarily suitable for the photoelectrically conductive coatings are, in particular, foils made of metal, e.g., aluminum, zinc and copper, cellulose products such as paper, paper toils laminated to metal, cellulose hydrate, and cellulose esters such as cellulose acetate and cellulose butyrate.
  • metal e.g., aluminum, zinc and copper
  • cellulose products such as paper, paper toils laminated to metal, cellulose hydrate, and cellulose esters such as cellulose acetate and cellulose butyrate.
  • paper is used as a supporting material, it is advisable for it to be pretreated to prevent the penetration of the coating solution, e.g., with a solution of methyl cellulose or polyvinyl alcohol in water or with a solution of an interpolymer of acrylic acid methyl ester and acrylonitrile in a mixture of acetone and methyl ethyl ketone or with solutions of polyamides in aqueous alcohols or with dispersions of such substances.
  • the coating solution e.g., with a solution of methyl cellulose or polyvinyl alcohol in water or with a solution of an interpolymer of acrylic acid methyl ester and acrylonitrile in a mixture of acetone and methyl ethyl ketone or with solutions of polyamides in aqueous alcohols or with dispersions of such substances.
  • sensitizers are added in small quantities, i.e., about 0.0001 to 0.5% by weight of the solid substance, both to the solutions containing the insulating resin and to the solutions of the photosemiconductor.
  • sensitizers which are primarily dyestuffs, are disclosed, for example, in Belgian Patent No. 558,078.
  • Fillers and pigments such as kaolin, titanium dioxide and barium sulfate may also be added to the coating solutions in quantities of up to 30% by weight.
  • paper, textiles, metals such as aluminum, copper and iron, cellulose hydrate foils or plastic foils are used as supporting materials. These supporting materials are coated with a solution of insulating natural or synthetic resins such as polystyrene, polyisobutylene, chlorinated rubber, polyvinyl chloride, chlorinated polyvinyl chloride, polyvinyl carbazole, colophony, cournarone resins and inorganic photosemiconductors.
  • the supports may be coated on both sides or on one side only.
  • Example I 60 parts by weight of a polymethacrylic acid methyl ester (Plexigum M7553) are dissolved in 320 parts by weight of toluene. To this solution, a solution of 0.05 part by weight of Rhodamine B extra (Schultz, Farbstof" tabellen, 7th edition, vol. 1 (1931), No. 864) in 39 parts by weight of methanol is first added, with stirring, and then parts by weight of extra pure zinc oxide is dispersed in the solvent mixture with a high-speed agitator. The suspension thus obtained has a viscosity of 50-55 seconds, as measured in a 2 mm. Ford beaker. This suspension is mechanically coated upon paper. The thickness of the coating, here designated as coating 2, should be 6 to 8,. After drying, the paper is exposed under a positive film mastertor 5 seconds to a 250 watt exposed coating.
  • coating 2 The thickness of the coating, here designated as coating 2 should be 6 to 8,.
  • a paper coated With 8 parts by Weight of chlorinated rubber in 100 parts by volume of benzene is then placed on the exposed coating with its coating, here designated as coating a, on the image and the back is sprayed with negative charge, e.g., with a corona discharge.
  • coating a On the chlorinated rubber coating a, a larterally reversed, invisible electrostatic image of coating 2, consisting of positive charges, is first formed.
  • the paper is now treated on the coated side thereof with a developer consisting of tiny glass balls and a very finely divided resin/carbon black mixture.
  • the resin/ carbon black toner becomes positively charged; it is repelled from the positively charged image parts and settles on the uncharged parts.
  • An image is formed which is laterally reversed negative with respect to the image on the coating 2 and a positive mirror image with respect to the original. It is slightly heated and thereby made durable (fixed); it shows good contrast. A number of copies can be prepared in this Way from the exposed photoelectrically conductive insulator coating 2.
  • Example II 300 parts by weight of toluene are added to a solution of 160 parts by Weight of a methyl silicone resin (50% in toluene) and this solution is mixed, by stirring, with a second solution consisting of 40 parts by weight of methanol and 0.2 part by weight of Acid Violet 6 EN (Schultz, Parbstolltabellen, 7th edition, vol. 1, No. 831).
  • a second solution consisting of 40 parts by weight of methanol and 0.2 part by weight of Acid Violet 6 EN (Schultz, Parbstolltabellen, 7th edition, vol. 1, No. 831).
  • Into this mixture 190 parts by weight of zinc sulfide, a product commercially available under the name Sachtolith, are stirred and then disperscd by repeated grinding in a colloid mill. Further procedure is as described in Example 1.
  • tae paper After drying, tae paper is placed coated side down on a page of a book with printing on both sides and is then exposed for seconds to a 100 watt filament lamp. The light thus passes through the paper. After the exposure a paper that has been coated on both sides with a solution of 8 parts by weight of polyvinyl carbazole in 100 parts by volume of toluene is placed on the The exterior polyvinyl carbazole coat ing is then negatively charged and the coating that has been facing the latent image is developed With a developer as described in Example I. A non-reversed image of the master is obtained.
  • Example III 95 parts by Weight of cadmium sulfide are introduced into a solution of 80 parts by Weight of methyl silicone resin (50% in toluene), 100 parts by weight of toluene and 25 parts by weight of methanol and the mixture is homogenized by means of a high-speed agitator. This suspension is coated upon a transparent paper the surface of which has been pretreated to prevent the penetration of organic solvents and the coated paper is dried. Further procedure is as described in Example I, a mirror image of a page of a book with printing on both sides being projected with a camera upon the cadmium sulfide coating.
  • An electrophotographic reproduction process which comprises producing a latent resistance image in a first photoconductive insulator layer containing an inorganic photosemiconductor by exposure of the layer to a light image, then placing a supported second photoconductive insulator layer in surface contact with the first layer with the layers facing each other, electrostatically charging the second layer by applying an electrostatic charge to the support for the second layer on the side remote from the second layer and developing at least'one of the latent electrostatic images produced.
  • photoelectrically conductive insulator layers include a sensitizer.

Description

I of zinc, bismuth, mium.
ire ts In copending application Serial No. 150,458, filed November 6, 1961, there is described an electrophotographic reproduction process in which a latent resistance image is produced by the imagewise exposure to light of photoelectrically conductive but non-electrostatically charged insulator layer consisting of or containing organic photosemiconductors, a photoelectrically conductive but nonelectrostatically charged insulator layer on a supporting material is placed on this latent resistance image, the whole is electrostatically charged from the supporting material side and the latent electrostatic image produced on the photoelectrically conductive coating of the superposed supporting material is made visible by known methods of electrophotography and may then be fixed, whereupon a mirror image of the latent resistance image is formed.
, In this process, it is also possible for a supporting material to be used which is covered on both sides with the photoelectrically conductive insulator coating and the whole is then electrostatically charged from the supporting material side. The latent electrostatic image, produced on the coating remote from the latent resistance image to be reproduced, is made visible by the aforementioned methods and, where necessary, fixed, a nonreversed image of the latent resistance image thus being formed.
The present invention relates to an electrophotographic reproduction process in which a latent resistance image is produced by imagewise exposure of a photoelectrically conductive but non-electrostatically charged insulator layer consisting of or containing inorganic photoserniconductors, a, photoelectrically conductive but nonelectrostatically charged insulator layer on a supporting material is placed on this latent resistance image, the whole is electrostatically charged from the supporting material side and the latent electrostatic image produced on the photoelectrically conductive coating of the superposed supporting material is made visible by known methods of electrophotography and may then be fixed, whereupon a mirror image of the latent resistance image is formed. In this process too, it is possible for a supporting material to be used which is covered on both sides with the photoelectrically conductive insulator layer, the whole electrostatically charged from the supporting material side and the latent electrostatic image, produced on the layer remote from the latent resistance image which is to be reproduced, made visible by the aforementioned methods and where necessary fixed, whereupon a nonreversed image of the latent resistance image is formed.
The photoconductive coatings for the production of latent images are inorganic photoconductive substances, e.g., the oxides, sulfides, selenides, tellurides and iodides molybdenum, lead, antimony and cadchloride, ethylene glycol monomethyl ether or other organic solvents in which they will disperse readily, or in 3,i59,%2 Patented Feb. 9, 1965 mixtures of such solvents. The supporting material is coated with these dispersions in the normal manner, by immersion, painting, roller application or by spraying. The material is then heated to remove the liquid components.
Further, it is advantageous in this process also for the photoconductive compounds to be used together with organic resins, such as are described in the copending application, supra.
The inorganic photoelectrically conductive compounds are applied to the supporting material, with or without the resins, in known manner, e.g., by painting, roller application, immersion or spraying. The coating is then dried, whereupon an even, photoelectrically conductive coating is formed.
Supports primarily suitable for the photoelectrically conductive coatings are, in particular, foils made of metal, e.g., aluminum, zinc and copper, cellulose products such as paper, paper toils laminated to metal, cellulose hydrate, and cellulose esters such as cellulose acetate and cellulose butyrate.
If paper is used as a supporting material, it is advisable for it to be pretreated to prevent the penetration of the coating solution, e.g., with a solution of methyl cellulose or polyvinyl alcohol in water or with a solution of an interpolymer of acrylic acid methyl ester and acrylonitrile in a mixture of acetone and methyl ethyl ketone or with solutions of polyamides in aqueous alcohols or with dispersions of such substances.
To increase the light sensitvity of the reproduction coatings in the visible range of the spectrum, sensitizers are added in small quantities, i.e., about 0.0001 to 0.5% by weight of the solid substance, both to the solutions containing the insulating resin and to the solutions of the photosemiconductor. Such sensitizers, which are primarily dyestuffs, are disclosed, for example, in Belgian Patent No. 558,078.
Fillers and pigments such as kaolin, titanium dioxide and barium sulfate may also be added to the coating solutions in quantities of up to 30% by weight.
For the production of non-reversed copies from the latent image, paper, textiles, metals such as aluminum, copper and iron, cellulose hydrate foils or plastic foils are used as supporting materials. These supporting materials are coated with a solution of insulating natural or synthetic resins such as polystyrene, polyisobutylene, chlorinated rubber, polyvinyl chloride, chlorinated polyvinyl chloride, polyvinyl carbazole, colophony, cournarone resins and inorganic photosemiconductors. The supports may be coated on both sides or on one side only.
With the process of the invention either mirror image or nonreversed positive or negative reproductions of excellent quality are successfully obtained.
The method for the preparation of photoelectric mirror image copies is described below:
Example I 60 parts by weight of a polymethacrylic acid methyl ester (Plexigum M7553) are dissolved in 320 parts by weight of toluene. To this solution, a solution of 0.05 part by weight of Rhodamine B extra (Schultz, Farbstof" tabellen, 7th edition, vol. 1 (1931), No. 864) in 39 parts by weight of methanol is first added, with stirring, and then parts by weight of extra pure zinc oxide is dispersed in the solvent mixture with a high-speed agitator. The suspension thus obtained has a viscosity of 50-55 seconds, as measured in a 2 mm. Ford beaker. This suspension is mechanically coated upon paper. The thickness of the coating, here designated as coating 2, should be 6 to 8,. After drying, the paper is exposed under a positive film mastertor 5 seconds to a 250 watt exposed coating.
photographic bulo at a distance of 40 cm. A paper coated With 8 parts by Weight of chlorinated rubber in 100 parts by volume of benzene is then placed on the exposed coating with its coating, here designated as coating a, on the image and the back is sprayed with negative charge, e.g., with a corona discharge. On the chlorinated rubber coating a, a larterally reversed, invisible electrostatic image of coating 2, consisting of positive charges, is first formed. The paper is now treated on the coated side thereof with a developer consisting of tiny glass balls and a very finely divided resin/carbon black mixture. As a result of friction against the glass balls, the resin/ carbon black toner becomes positively charged; it is repelled from the positively charged image parts and settles on the uncharged parts. An image is formed which is laterally reversed negative with respect to the image on the coating 2 and a positive mirror image with respect to the original. It is slightly heated and thereby made durable (fixed); it shows good contrast. A number of copies can be prepared in this Way from the exposed photoelectrically conductive insulator coating 2.
Similarly, it is possible for a visible image to be pr..- pared if coating 2, after being exposed and charged, is treated with the developer and then fixed.
Example II 300 parts by weight of toluene are added to a solution of 160 parts by Weight of a methyl silicone resin (50% in toluene) and this solution is mixed, by stirring, with a second solution consisting of 40 parts by weight of methanol and 0.2 part by weight of Acid Violet 6 EN (Schultz, Parbstolltabellen, 7th edition, vol. 1, No. 831). Into this mixture 190 parts by weight of zinc sulfide, a product commercially available under the name Sachtolith, are stirred and then disperscd by repeated grinding in a colloid mill. Further procedure is as described in Example 1. After drying, tae paper is placed coated side down on a page of a book with printing on both sides and is then exposed for seconds to a 100 watt filament lamp. The light thus passes through the paper. After the exposure a paper that has been coated on both sides with a solution of 8 parts by weight of polyvinyl carbazole in 100 parts by volume of toluene is placed on the The exterior polyvinyl carbazole coat ing is then negatively charged and the coating that has been facing the latent image is developed With a developer as described in Example I. A non-reversed image of the master is obtained.
Example III 95 parts by Weight of cadmium sulfide are introduced into a solution of 80 parts by Weight of methyl silicone resin (50% in toluene), 100 parts by weight of toluene and 25 parts by weight of methanol and the mixture is homogenized by means of a high-speed agitator. This suspension is coated upon a transparent paper the surface of which has been pretreated to prevent the penetration of organic solvents and the coated paper is dried. Further procedure is as described in Example I, a mirror image of a page of a book with printing on both sides being projected with a camera upon the cadmium sulfide coating.
For the preparation of a copy the procedure is as described in Example I.
it Will be obvious to those skilled in the art that many modifications may be made Within the scope of the present invention Without departing from the spirit thereof, and the invention includes all such modifications.
What is claimed is:
1. An electrophotographic reproduction process which comprises producing a latent resistance image in a first photoconductive insulator layer containing an inorganic photosemiconductor by exposure of the layer to a light image, then placing a supported second photoconductive insulator layer in surface contact with the first layer with the layers facing each other, electrostatically charging the second layer by applying an electrostatic charge to the support for the second layer on the side remote from the second layer and developing at least'one of the latent electrostatic images produced.
2. An electrophotographic reproduction process according to claim 1 in Which the support for the second layer has a photoclectrically conductive insulator layer on only one side thereof.
3. An electrophotographic reproduction process according to claim 1 in which the support for the second layer has a photoelectrically conductive insulator layer on both sides thereof.
4. An electrophotographic reproduction process according to claim 3 in which the latent electrostatic image on the layer on the side of the support remote from the second layer is developed.
5. An electrophotographic reproduction process according to claim 1 in which the first layer is on a support.
6. An electrophotographic process according to claim' 1 in which the second photoelectrically conductive insulator layer comprises an organic photosemicondutor;
7. An electrophotographic reproduction process according to claim 1 in which the second photoelectrically conductive insulator layer comprises an inorganic photosemiconductor.
8. An electrophotographic reproduction process according to claim 1 in which the photoelectrically conductive insulator layers include a resin.
9. An electrophotographic reproduction process according to claim 1 in which photoelectrically conductive insulator layers include a sensitizer. l
10. An electrophotographic reproduction process according to claim 1 in which the photoelectrically conductive insulator layers include a filler.
References fitted in the tile of this patent UNITED STATES PATENTS 2,817,277 Bogdonotf Dec. 24, 1957 2,825,814 Walkup Mar. 4, 1958 2,833,930 Walkup May 6, 1958 3,011,918 Silvernail et al. Dec. 5, 1961 3,051,569 Sugarman et a1 Aug. 28, 1962 3,057,719 Byrne et al. Oct. 9, 1962 3,084,061 Hall Apr. 2, 1963 FOREIGN PATENTS 168,181 Australia Dec. 7, 1956

Claims (1)

1. AN ELECTROPHOTOGRAPHIC REPRODUCTION PROCES WHICH COMPRISES PRODUCING A LATENT RESISTANCE IMAGE IN A FIRST PHOTOCONDUCTIVE INSULATOR LAYER CONTANINING AN INORGANIC PHOTOSEMIDONDUCTOR BY EXPOSURE OF THE LAYER TO A LIGHT IMAGE, THEN PLACING A SUPPORTED SECOND PHOTOCONDUCTIVE INSULATOR LAYER IN SURFACE CONTACT WITH THE FIRST LAYER WITH THE LAYERS FACING EACH OTHER, ELECTROSTATICALLY CHARGING THE SECOND LAYER BY APPLYING AN ELECTROSTATIC CHARGE TO THE SUPPORT FOR THE SECOND LAYER ON THE SIDE REMOTE FROM THE SECOND LAYER AND DEVELOPING AT LEAST ONE OF THE LATENT ELECTROSTATIC IMAGES PRODUCED.
US181433A 1961-01-14 1962-03-21 Electrophotographic reproduction process Expired - Lifetime US3169062A (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DEK42644A DE1206307B (en) 1961-01-14 1961-01-14 Electrophotographic process for making images
DEK43273A DE1220253B (en) 1961-01-14 1961-03-23 Electrophotographic process for making images
DE3169062X 1961-03-23
FR884390A FR1309799A (en) 1961-01-14 1962-01-10 Electrophotographic reproduction process

Publications (1)

Publication Number Publication Date
US3169062A true US3169062A (en) 1965-02-09

Family

ID=27437114

Family Applications (1)

Application Number Title Priority Date Filing Date
US181433A Expired - Lifetime US3169062A (en) 1961-01-14 1962-03-21 Electrophotographic reproduction process

Country Status (2)

Country Link
US (1) US3169062A (en)
FR (1) FR1309799A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3477846A (en) * 1967-05-01 1969-11-11 Gaf Corp Xerographic charge transfer process
US3589290A (en) * 1966-05-20 1971-06-29 Xerox Corp Relief imaging plates made by repetitive xerographic processes

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2817277A (en) * 1955-01-07 1957-12-24 Haloid Co Electrophotographic camera
US2825814A (en) * 1953-07-16 1958-03-04 Haloid Co Xerographic image formation
US2833930A (en) * 1953-07-16 1958-05-06 Haloid Co Electrostatic charging method and apparatus
US3011918A (en) * 1959-05-29 1961-12-05 Dow Chemical Co Electroconductive coated paper and method of making the same
US3051569A (en) * 1959-10-26 1962-08-28 American Photocopy Equip Co Photoconductive materials
US3057719A (en) * 1958-07-09 1962-10-09 Xerox Corp Process for forming electrostatic images
US3084061A (en) * 1953-09-23 1963-04-02 Xerox Corp Method for formation of electro-static image

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2825814A (en) * 1953-07-16 1958-03-04 Haloid Co Xerographic image formation
US2833930A (en) * 1953-07-16 1958-05-06 Haloid Co Electrostatic charging method and apparatus
US3084061A (en) * 1953-09-23 1963-04-02 Xerox Corp Method for formation of electro-static image
US2817277A (en) * 1955-01-07 1957-12-24 Haloid Co Electrophotographic camera
US3057719A (en) * 1958-07-09 1962-10-09 Xerox Corp Process for forming electrostatic images
US3011918A (en) * 1959-05-29 1961-12-05 Dow Chemical Co Electroconductive coated paper and method of making the same
US3051569A (en) * 1959-10-26 1962-08-28 American Photocopy Equip Co Photoconductive materials

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3589290A (en) * 1966-05-20 1971-06-29 Xerox Corp Relief imaging plates made by repetitive xerographic processes
US3477846A (en) * 1967-05-01 1969-11-11 Gaf Corp Xerographic charge transfer process

Also Published As

Publication number Publication date
FR1309799A (en) 1962-11-16

Similar Documents

Publication Publication Date Title
US3113022A (en) Electrophotographic process
US3869285A (en) Plate-making master and method for producing a printing plate which does not require dampening water
US3274000A (en) Electrophotographic material and method
US3081165A (en) Xerographic chemography
US3206306A (en) Material for electrophotographic purposes
US3438773A (en) Flexible transparent electrophotographic film and method of development of said film
DE1117391B (en) Electrophotographic process for the production of printing forms
US3311490A (en) Developing electrostatic charge image with a liquid developer of two immiscible phases
US3795011A (en) Electrostatic printing device
US3406063A (en) Xerographic material containing an inorganic photoconductor and nonpolymeric crystalline organic substances and methods of using of such material
US3376133A (en) Multicolor electrostatic printing
US3169062A (en) Electrophotographic reproduction process
US3820984A (en) Method of migration imaging using fusible particles
US3677750A (en) Photoelectrosolographic imaging process
US3808026A (en) Liquid development of electrostatic latent image
US3163530A (en) Material for electrophotographic purposes
US3721552A (en) Electrophotographic reproduction material
US3256197A (en) Liquid developer for electrostatic charge images
US3770428A (en) PHOTOCONDUCTIVE REACTION PRODUCT OF N -beta- CHLORETHYL CARBAZOLE AND FORMALDEHYDE
US3285740A (en) Electrophotographic process
US3676118A (en) Reflex xerographic imaging system
US3250614A (en) Methods and materials for the removal of the sensitizing dye(s) from electrophotograpic prints
US3684506A (en) Dimeric poly-n-vinyl carbazole organic photoconductor and photoconductive elements embodying same
US3373020A (en) Electrophotographic material and process employing metal resinates
US3290146A (en) Electrophotographic material and process