US3281241A - Method of forming a visual record of a latent image on an image receiving web - Google Patents

Method of forming a visual record of a latent image on an image receiving web Download PDF

Info

Publication number
US3281241A
US3281241A US206987A US20698762A US3281241A US 3281241 A US3281241 A US 3281241A US 206987 A US206987 A US 206987A US 20698762 A US20698762 A US 20698762A US 3281241 A US3281241 A US 3281241A
Authority
US
United States
Prior art keywords
image
support member
developer
web
foil
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
US206987A
Other languages
English (en)
Inventor
Vsevolod S Mihajlov
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.)
Xerox Corp
Original Assignee
Xerox 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 to DENDAT1303008D priority Critical patent/DE1303008B/de
Application filed by Xerox Corp filed Critical Xerox Corp
Priority to US206987A priority patent/US3281241A/en
Priority to GB25392/63A priority patent/GB1035236A/en
Priority to FR940163A priority patent/FR1362254A/fr
Application granted granted Critical
Publication of US3281241A publication Critical patent/US3281241A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G9/00—Developers
    • G03G9/08—Developers with toner particles
    • G03G9/12—Developers with toner particles in liquid developer mixtures
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G13/00—Electrographic processes using a charge pattern
    • G03G13/06—Developing
    • G03G13/10—Developing using a liquid developer, e.g. liquid suspension

Definitions

  • a latent electrostatic image formed on a reusable non-conductive support is rendered visible by dusting with finely divided oppositely charged toner particles.
  • This toner image may then be transferred to an image receiving websuch as ordinary paper and fixed thereon by heat fusing or the like.
  • Liquid development techniques have also been successfully employed and are of particular importance because of the generally high degree of image resolution obtainable thereby. Liquid development also provides more complete coverage of solid area images, as distinct from line copy, than is ordinarily obtainable with dry developer systems without special control elements.
  • the liquid immersion method comprises immersing the plate supporting an electrostatic image into a developer made up of finely divided particles suspended in an insulating liquid. Either the charged or the uncharged areas of the plate are developed as desired depending upon the polarity of the charge on the particles.
  • Image resolution as high as 600 lines per mm. has reportedly been attained by this method and although image quality is generally superior there are distinct disadvantages inherent in the immersion method. In particular, it normally involves the handling of fairly large quantities of frequently volatile and sometimes toxic liquids. Also it has been found that images developed by this method are not readily transferable by conventional methods.
  • Another liquid development method comprises pouring the developer across the charged and exposed plate. Generally good results are attainable, but the disadvantages already mentioned are applicable. In addition, this technique is rather sloppy. Still another method of liquid development comprises rolling a plate bearing an electrostatic charge pattern across a roller which is partially immersed in developer. The roller serves as a means to transfer the developer from a supply tank to the plate and at the same time, may act as an electrode. Again, the disadvantages of handling large quantities of liquid and the inconvenience of transfer are present.
  • a visible record of an electrostatic image may be formed directly on an image receiving web by a liquid development tech nique from which the disadvantages commonly associated with liquid development have been eliminated.
  • the present invention not only obviates the usual separate transfer step, it also provides for the production of multiple copies from a single electrostatic image.
  • this invention comprises placing a small quantity of liquid developer containing dye particles, charged to the same polarity as the image to be developed, near the edge of a plate supporting a latent electrostatic image. Successive portions of an image receiving material .are then brought into close cont-act with successive portions of the plate while a bead of developer is advanced in front of the leading edge of the paper as it comes into contact with the plate. A visible record of the image is thereby produced directly on the receiving material. By merely repeating these steps, additional copies conforming to the charge pattern may be made.
  • the principal object of this invention is to provide a novel method for producing a visible record conforming to a latent electrostatic image.
  • Another object of this invention is to provide a novel method to develop the copy of an electrostatic image directly on an image receiving web.
  • Another object of this invention is to provide a liquid development system for producing multiple copies from an electrostatic image.
  • Still another object of this invention is to provide a liquid development system requiring the handling of only small quantities of liquid thereby reducing the expense, minimizing vapors released, and inconvenience commonly associated with liquid development.
  • FIGURE 1 is an isometric view of a layer developable in accordance with this invention
  • FIGURE 2 is a schematic representation of liquid development according to the present invention.
  • FIGURE 3 is an isometric view illustrating the instant liquid development method.
  • FIGURE 1 Illustrated in FIGURE 1 is an image system applicable to the present invention.
  • Latent electrostatic image 11 on the surface of insulating plate 12 is designated by the plus marks and for purposes of this description is assumed to be of positive polarity. However, it is to be understood that the latent image may be of either positive or negative polarity and may consist of gradations of potential or charge or may be as illustrated in the figure areas of charge interspaced by areas of substantially no charge.
  • the particular image illustrated in FIGURE 1 may be regarded as a line copy image consisting of representative areas of charge and absence of charge which desirably can be printed as areas of black on a white surface.
  • Insulating plate 12 must be at least sufiiciently non-conductive to support an electrostatic charge during the instant process.
  • the conventional xerographic plate is suitable for this purpose, but it is not suggested that this invention is limited thereto.
  • FIGURE 2 is a schematic representation of the present invention. To more clearly present the invention, FIG- URE 2 has been broken up into three parts: (a), (b) and (c). In 2(a) there is shown an image system with developer, image receiving web and roller positioned as at the beginning of the instant process; FIGURE 2(b) shows the system with the roller rolled part way across the insulating plate; and in 2(0) is shown the system at the completion of the instant process. Each component appearing in more than one view has been assigned the same numerical designation in all views in which it appears. Plus marks designate latent electrostatic image 11 on or near the surface of insulating plate 12.
  • pressure roller 13 is positioned on the surface and near one edge of plate 12; image receiving web 14 is positioned at an angle in such manner that its leading edge rests on plate 12 immediately adjacent to and on the image side of roller 13; a bead of developer 15 is placed on the surface of plate 12 'between said leading edge of web 14 and said image 11.
  • the liquid developer employed in the present invention is described in detail below. It preferably comprises finely divided electrically charged dyestufl", herein termed toner, dispersed in a relatively non-conductive liquid carrier. For purposes of this description, the toner is assumed to be charged to the same polarity as that of latent electrostatic image 11.
  • pressure roller 13 is then rolled in the direction indicated by the arrow so that successive portions of web 14 are brought into intimate contact with successive portions of plate 12.
  • the lateral movement of roller 13 advances developer 15 across the surface of plate 12 in front of the pressure line created by roller 13.
  • Successive portions of web 14 are preferably separate from plate 12 after having been brought into intimate contact by the action of pressure roller 13.
  • Roller 13 desirably comprises an electrically conductive material, such as conductive rubber. However, other materials including non-conductive materials may also be used.
  • an electrical potential to the roller. Relatively small quantities of toner may adhere to the image receiving material in non-image areas thereby causing the appearance of background in the prints if the roller is allowed to electrically float. This undesired phenomenon can be appreciably reduced by app-lying an electrical potential of the same polarity as that of the toner to roller 13. Of course, the magnitude of this electrical potential must not be so great as to prevent deposition of toner in image areas. Generally this potential is between about ground and about the potential of the discharge areas of the surface bearing the charge pattern.
  • toner image 17 may be rendered permanent by an appropriate method such as pressure fixing, heat fusing or the like.
  • a liquid developer may be employed which is self-fixing. The various usable known developers are discussed below.
  • Developer compositions suitable for use in the present invention comprise dispersions of toner particles formed in a liquid carrier, for example, by stirring or other methods Well known to those skilled in the art. It is understood that the toner particles may be liquids, solids or organosols capable of being dispersed in the carrier. Thus, suitable dispersions, suspensions and emulsions and other collodial systems are within the scope of this invention.
  • the carrier liquid must be a highly insulating material, preferably with a volume resistivity of at least about 10 ohm centimeters, in order to avoid discharge of the latent electrostatic image.
  • Suitable liquids include hydrocarbons such as benzene, xylene, hexane, naphtha, cyclohexane, etc; halogenated hydrocarbons such as carbon tetrachloride, trichloroethylene, chloroform, Freons (a trade name of E. I. du Pont de Nemours & Co. for various fluorinated compounds), Genetrons (a trade name of Allied Chemical Co. for various fluorinated compounds), etc.; miscellaneous liquids such as silicone liquid, turpentine, etc.
  • a particularly useful material of refined petroleum hydrocarbon class is Sohio Odorless Solvent (SOS) sold by the Standard Oil Company of Ohio.
  • SOS Sohio Odorless Solvent
  • Suitable viscosity agents such as parafiin wax, liquid petrolatum, etc., may be added to increase the viscous drag of the carrier.
  • Liquid toner particles mus-t be substantially immiscible with the carrier liquid and capable of ⁇ being dispersed in the form of very small droplets.
  • suitable materials which may be used in conjunction with the present invention.
  • One suitable class of materials comprises aqueous inks such as ordinary commercial fountain pen inks.
  • Another particularly useful class of materials includes glycols, preferably including soluble dyes in order to render the image visible.
  • Particularly suitable examples include ethylene glycol promptaining about 5% of crystal violet of malachite green
  • Suitable solid toner particles include pigments, dyes, resins, metals, and materials such as charcoal and graphite and similar material, having a fine particle size and being insoluble in the carrier liquid. In general, the finer the powder the better the grain in the developed image. It is preferred that the average particle size be no larger than about 20 microns and for high quality work, it is preferred that the average particle size be no more than about 5 microns.
  • the toner image is typically rendered permanent by a separate fixing step such as heat fusing or the like.
  • the separate fixing step may be obviated by an appropriate selection of developer components.
  • self-fixing characteristics may be imparted to the developer by using toner particles comprising resins which are binders or film-forming.
  • a composition suitable for this purpose comprises an organosol in which a solution of a resin binder in a polar solvent is dispersed in a non-polar carrier.
  • Another suitable composition comprises a suspension of finely divided resin dyes-tufi? in molten parafi'in wax. solidification of the wax upon cooling to room temperature serves to fix the image to the image receiving web.
  • roller pressure may vary over a wide range without deleteriously affecting image production.
  • sufiicient pressure be exerted to bring the image receiving Web into intimate contact with the plate supporting the electrostatic image and to cause the developer to travel across the plate so that it will be brought into operative proximity with the electrostatic charge and the image receiving web.
  • reversal development, or deposition conforming to uncharged areas may be accomplished by using a suitable toner which is oppositely charged with respect to the electrostatic image on the plate.
  • a suitable toner which is oppositely charged with respect to the electrostatic image on the plate.
  • the electrical bias applied to the roller may again be selected to influence both image density and background density of the prints.
  • good quality line copy prints may be made according to the instant invention on baryta-coated paper from an electrostatic image of positive polarity varying over a range of a maximum of about 600 volts and a minimum of about ground by using approximately 0.2 ml. of a developer comprising by weight of toner suspended in a suspending medium comprising paraffin wax and Sohio Odorless Solvent, applying a positive electrical bias of the order of about 100 volts to the pressure roller, and using a roller speed in the order of 3040 seconds per pass over a 4 x 5 inch plate.
  • the method of forming on an image receiving web a visual record of a latent electrostatic image on an image support member comprising placing an individual droplet of developer comprising particulate electrical-1y charged toner suspended in a non-conductive liquid carrier on said image support member, simultaneously establishing a line of intimate physical contact between successive portions of said image receiving web and said image support member and advancing said line, said developer advancing in front of said line of intimate physical contact and between said image receiving web and said image support member to deposit said toner particles on said image receiving web in image configuration at said line of intimate physical contact, and separating said web from said image support member bearing a developed image.
  • the method of depositing toner particles on an image receiving web in conformity with a latent electrostatic image on an image support member comprising placing an individual droplet of developer comprising electrically charged toner particles suspended in a non-conductive liquid carrier onto said support member, bringing successive portions of said web into intimate contact with successve port-ions of said support member by rolling a cylindrical roller across said web and simultaneously advancing said developer before the line of contact between said web and said support member, and separating said web from said image support member.
  • a method for forming on an image receiving web a visual record of a latent electrostatic image on an image support member comprising advancing developer comprising electrically charged toner particles suspended in a non-conductive liquid carrier across said support member by establishing a line of intimate physical contact between successive portions of said web and said support member whereby toner particles are selectively deposited on said web in image configuration, and separating said web from said support member.
  • liquid carrier is a refined petroleum hydrocarbon having a resistivity of at least about 10 ohm centimeters.
  • said particulate toner comprises finely divided powder particles the average size of which particles is no larger than about 20 microns.
  • said particulate toner comprises a solution of resin in a solvent therefor and said liquid carrier comprises a non-polar organic liquid.
  • said particulate toner comprises a solution of resin in a solvent therefor and including the additional step of fixing said toner particles deposited on said image receiving web by eliminating the solvent therefrom.
  • a method for xerographic image reproduction comprising applying an electrostatic charge of one polarity to the surface of a xerographic plate, exposing said plate to a pattern of light and shadow, placing an individual droplet of developer comprising electrically charged particles suspended in a nonconductive liquid carrier on the said plate, establishing a line of intimate physical contact between successive portions of said plate and an image receiving web and advancing said developer in front of said line of contact whereby printing of a visible record of said latent electrostatic image is elfected on said web, and separating said web from said xerographic plate.
  • liquid developer comprises electrically charged particulate toner suspended in a non-conductive liquid carrier.
  • the method of producing a visible record of a latent electrostatic image formed on an image support member including:

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Liquid Developers In Electrophotography (AREA)
  • Wet Developing In Electrophotography (AREA)
  • Fixing For Electrophotography (AREA)
US206987A 1962-07-02 1962-07-02 Method of forming a visual record of a latent image on an image receiving web Expired - Lifetime US3281241A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
DENDAT1303008D DE1303008B (enrdf_load_stackoverflow) 1962-07-02
US206987A US3281241A (en) 1962-07-02 1962-07-02 Method of forming a visual record of a latent image on an image receiving web
GB25392/63A GB1035236A (en) 1962-07-02 1963-06-26 Improvements in xerographic development
FR940163A FR1362254A (fr) 1962-07-02 1963-07-02 Procédé de formation d'enregistrements visibles d'une image électrostatique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US206987A US3281241A (en) 1962-07-02 1962-07-02 Method of forming a visual record of a latent image on an image receiving web

Publications (1)

Publication Number Publication Date
US3281241A true US3281241A (en) 1966-10-25

Family

ID=22768758

Family Applications (1)

Application Number Title Priority Date Filing Date
US206987A Expired - Lifetime US3281241A (en) 1962-07-02 1962-07-02 Method of forming a visual record of a latent image on an image receiving web

Country Status (4)

Country Link
US (1) US3281241A (enrdf_load_stackoverflow)
DE (1) DE1303008B (enrdf_load_stackoverflow)
FR (1) FR1362254A (enrdf_load_stackoverflow)
GB (1) GB1035236A (enrdf_load_stackoverflow)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3419411A (en) * 1963-09-06 1968-12-31 Australia Res Lab Method for the transfer of developed electrostatic images using a lattice forming substance
US3720183A (en) * 1967-11-08 1973-03-13 Ricoh Kk Transfer device for images by the use of liquid development electrophotography
US3854813A (en) * 1972-01-01 1974-12-17 A Kaufman Electrostatic printing apparatus using charge induced toning
US4325625A (en) * 1977-03-07 1982-04-20 Olympus Optical Company Limited Electrophotographing method
US4329043A (en) * 1978-05-25 1982-05-11 Coulter Systems Corporation Multiple copy electrophotographic reproducing apparatus
US4365885A (en) * 1977-10-24 1982-12-28 Olympus Optical Company Limited Apparatus for removing unnecessary charges on a photosensitive member in an electrophotographic system
US4391502A (en) * 1977-09-12 1983-07-05 Olympus Optical Company Limited Electrophotographic apparatus having means for adjusting the reproduction properties of subsequent copies after a first copy has been produced
EP1127625A3 (en) * 2000-02-25 2004-07-28 Samsung Electronics Co., Ltd. Sheet coating apparatus
US20090034108A1 (en) * 2007-02-09 2009-02-05 Fujifilm Corporation Transfer method, transfer apparatus, and recording medium

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2847305A (en) * 1954-12-16 1958-08-12 Haloid Xerox Inc Xerographic transfer process
US2899335A (en) * 1956-10-31 1959-08-11 Process for developing electrostatic
US2907674A (en) * 1955-12-29 1959-10-06 Commw Of Australia Process for developing electrostatic image with liquid developer
US3003871A (en) * 1955-09-29 1961-10-10 Polaroid Corp Photographic apparatus and process for treating light-sensitive material
US3013890A (en) * 1958-07-08 1961-12-19 Xerox Corp Process of developing electrostatic images and composition therefor
US3063859A (en) * 1955-03-01 1962-11-13 Xerox Corp Method and apparatus for transferring images from xerographic to metallic plates
US3120446A (en) * 1961-02-01 1964-02-04 Xerox Corp Method of transferring a developed solid particulate image

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2847305A (en) * 1954-12-16 1958-08-12 Haloid Xerox Inc Xerographic transfer process
US3063859A (en) * 1955-03-01 1962-11-13 Xerox Corp Method and apparatus for transferring images from xerographic to metallic plates
US3003871A (en) * 1955-09-29 1961-10-10 Polaroid Corp Photographic apparatus and process for treating light-sensitive material
US2907674A (en) * 1955-12-29 1959-10-06 Commw Of Australia Process for developing electrostatic image with liquid developer
US2899335A (en) * 1956-10-31 1959-08-11 Process for developing electrostatic
US3013890A (en) * 1958-07-08 1961-12-19 Xerox Corp Process of developing electrostatic images and composition therefor
US3120446A (en) * 1961-02-01 1964-02-04 Xerox Corp Method of transferring a developed solid particulate image

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3419411A (en) * 1963-09-06 1968-12-31 Australia Res Lab Method for the transfer of developed electrostatic images using a lattice forming substance
US3720183A (en) * 1967-11-08 1973-03-13 Ricoh Kk Transfer device for images by the use of liquid development electrophotography
US3854813A (en) * 1972-01-01 1974-12-17 A Kaufman Electrostatic printing apparatus using charge induced toning
US4325625A (en) * 1977-03-07 1982-04-20 Olympus Optical Company Limited Electrophotographing method
US4391502A (en) * 1977-09-12 1983-07-05 Olympus Optical Company Limited Electrophotographic apparatus having means for adjusting the reproduction properties of subsequent copies after a first copy has been produced
US4365885A (en) * 1977-10-24 1982-12-28 Olympus Optical Company Limited Apparatus for removing unnecessary charges on a photosensitive member in an electrophotographic system
US4329043A (en) * 1978-05-25 1982-05-11 Coulter Systems Corporation Multiple copy electrophotographic reproducing apparatus
EP1127625A3 (en) * 2000-02-25 2004-07-28 Samsung Electronics Co., Ltd. Sheet coating apparatus
US20090034108A1 (en) * 2007-02-09 2009-02-05 Fujifilm Corporation Transfer method, transfer apparatus, and recording medium
US7804654B2 (en) * 2007-02-09 2010-09-28 Fujifilm Corporation Transfer method, transfer apparatus, and recording medium

Also Published As

Publication number Publication date
FR1362254A (fr) 1964-05-29
GB1035236A (en) 1966-07-06
DE1303008B (enrdf_load_stackoverflow)

Similar Documents

Publication Publication Date Title
US3301675A (en) Electrostatic photographic process of making multi-colored prints
US4021586A (en) Method of and means for the development of electrostatic images
US3574614A (en) Process of preparing multiple copies from a xeroprinting master
US3068115A (en) Electrostatic emulsion development
US4413048A (en) Developing composition for a latent electrostatic image for transfer of the developed image across a gap to a carrier sheet
US4268597A (en) Method, apparatus and compositions for liquid development of electrostatic images
GB672767A (en) Electrophotography
US3776723A (en) Improved liquid transfer electrophotographic development process
US3311490A (en) Developing electrostatic charge image with a liquid developer of two immiscible phases
US3281241A (en) Method of forming a visual record of a latent image on an image receiving web
US3627557A (en) Liquid development by reducing the viscosity of the developer on a roller applicator prior to development
US2913353A (en) Method and apparatus for developing electrostatic image
US4761357A (en) Electrophoretic development of electrostatic charge images
US3894512A (en) Electrostatic developing apparatus
US3560204A (en) Printing by electrical attraction of inks
US3372027A (en) Xerographic liquid development
US3712728A (en) Reversal development
US3676215A (en) Imaging system
US3104169A (en) Production of printing blocks, resists, transparencies, prints and the like by electro-deposition
US3556784A (en) Electrostatic image development
US3949116A (en) Method of developing an electrostatic latent image in which shear stress is employed
US3120446A (en) Method of transferring a developed solid particulate image
US3251688A (en) Liquid transfer development
US4202913A (en) Method for liquid development of latent electrostatic images
US3244633A (en) Liquid developers for developing electrostatic images