US2898279A - Coating surfaces by employing an electrostatic field - Google Patents

Coating surfaces by employing an electrostatic field Download PDF

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Publication number
US2898279A
US2898279A US663742A US66374257A US2898279A US 2898279 A US2898279 A US 2898279A US 663742 A US663742 A US 663742A US 66374257 A US66374257 A US 66374257A US 2898279 A US2898279 A US 2898279A
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coating
electrode
liquid
deposition
particles
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US663742A
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English (en)
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Metcalfe Kenneth Archibald
Wright Robert John
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Commonwealth of Australia
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Commonwealth of Australia
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/14—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for applying magnetic films to substrates
    • H01F41/16—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for applying magnetic films to substrates the magnetic material being applied in the form of particles, e.g. by serigraphy, to form thick magnetic films or precursors therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D1/00—Processes for applying liquids or other fluent materials
    • B05D1/007—Processes for applying liquids or other fluent materials using an electrostatic field
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D18/00—Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
    • B29D7/00—Producing flat articles, e.g. films or sheets
    • B29D7/01—Films or sheets
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
    • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
    • B41M5/10—Duplicating or marking methods; Sheet materials for use therein by using carbon paper or the like
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/02—Use of particular materials as binders, particle coatings or suspension media therefor
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D13/00—Electrophoretic coating characterised by the process
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D13/00—Electrophoretic coating characterised by the process
    • C25D13/04—Electrophoretic coating characterised by the process with organic material
    • C25D13/06—Electrophoretic coating characterised by the process with organic material with polymers
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
    • D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
    • D21H23/22—Addition to the formed paper
    • D21H23/50—Spraying or projecting
    • 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
    • G03G5/05—Organic bonding materials; Methods for coating a substrate with a photoconductive layer; Inert supplements for use in photoconductive layers
    • 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
    • G03G5/08—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being inorganic
    • G03G5/087—Photoconductive 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
    • 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
    • G03G9/122—Developers with toner particles in liquid developer mixtures characterised by the colouring agents
    • 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
    • G03G9/13—Developers with toner particles in liquid developer mixtures characterised by polymer components
    • 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
    • G03G9/13—Developers with toner particles in liquid developer mixtures characterised by polymer components
    • G03G9/132—Developers with toner particles in liquid developer mixtures characterised by polymer components obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • 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
    • G03G9/135—Developers with toner particles in liquid developer mixtures characterised by stabiliser or charge-controlling agents
    • 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
    • G03G9/135—Developers with toner particles in liquid developer mixtures characterised by stabiliser or charge-controlling agents
    • G03G9/1355—Ionic, organic compounds
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
    • G21K4/00—Conversion screens for the conversion of the spatial distribution of X-rays or particle radiation into visible images, e.g. fluoroscopic screens
    • 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 method and means for coating surfaces by electro-deposition with coating materials such as paint, paint pigments, ink, lacquer, wax resins, emulsions of various types, oils, dyes, gums, solutions and the like.
  • coating materials such as paint, paint pigments, ink, lacquer, wax resins, emulsions of various types, oils, dyes, gums, solutions and the like.
  • Such surfaces to be coated may be those associated with objects of regular or irregular shape, and may be of conducting or non-conducting or semi-com ducting material and may be of sheet form or plate form such as paper sheets or fabric sheets or plastic sheets or film.
  • Previously surfaces have been coated by means which include the application of paint and the like by means of brushes, knife coating devices, spray guns, air brushes, electrostatically-assisted spray guns, and by the assisted deposition of liquid paint from the air by electrostatic means.
  • spray guns and the like many difficulties arise in that the air operated gun is limited to a comparatively small volume of dispersion, and also causes the coating material to be dispersed in non-uniform sized particles, and in varying patterns and amounts in difierent areas.
  • the difiiculties encountered in this regard have given rise to an adaptation in which an electrostatic field is used to assist in distributing the particles more evenly. Further, in another adaptation an electrostatic field is used to drive liquid paint from an edge through the air on to an "object to be coated.
  • the object of the present invention is to coat surfaces with greater uniformity than heretofore possible, and to coat with a greater variety of materials and to arrange treatment so that eftective control can be exerted during treatment over the thickness and uniformity of deposition by control of the time and rate of deposition.
  • the invention consists in placing the material to be coated in a bath between electrodes which serve to deposit the coating material from the insulating bath on to the surface, with or without relative movement between the material and electrodes.
  • This invention will therefore be seen to relate to coating by electro-deposition effected in a bath of electrically insulating liquid having a dispersion of particles, colloids, emulsions, solutions, large molecules, emulsoids or gas, as opposed to the plating of articles by the prior methods of depositing through a conductive bath.
  • the principles underlying the invention are that when a bath of non-conducting liquid contains in it another dispersed substance Which is to form the coating material, the dispersed coating substance will be moved in such a bath when there is a field through the bath.
  • the actual apparatus for carrying out the invention can of course be very widely varied but may comprise a bath in which one electrode is a fixture and the other is the object or surface to be coated, or it may comprise a bath having electrodes which serve to deposit the coating material from the insulating bath on to the surface as the material moves or is disposed between the electrodes.
  • a roller may form one of the electrodes, and the materials to be treated may pass through this bath around the roller and be coated in so doing.
  • a belt or webbing can move in contact with such a roller and it can be of an insulating material or of a material which will enable it to act as an electrode, or in some cases where the coating material is to be applied to a material which can itself form an electrode, such material can simply be guided through the bath in proximity to the other electrode to effect the required coating.
  • the deposition depends in the first instance on the interesting phase boundary phenomena that occur when one of the phases in contact is an electrical insulator and the other consists of solid particles, colloids, liquid particles or globules, that is emulsions or emulsoids, gas pockets and the like held in suspension.
  • the solid or liquid particles suspended in an insulating liquid when an electrical field is applied.
  • the particles migrate either to the positive or negative electrode depending on the inherent charge of the particle.
  • the polarity of the charges on the particles will govern the direction in which they will move, that is, to which electrode they will move when a direct current electrical field is applied.
  • the chief action of the electrical field is in ensuring movement of the particles towards the electrode, and in producing a force which presses the particles together on the surface of the electrode.
  • the materials used for carrying out the invention can of course be very widely varied and that the coating materials used for coating can include all particles, resins, oils, waxes, dyes, gums, pigments and the like which can be dispersed in a liquid of suitably high volume resistivity.
  • the pigments and resins and the like can be mixed in such a way as to form a paint or paste of creamy or stiff consistency, unpolymerised or partly or nearly fully polymerised and ready for dispersal in the dispersing liquid.
  • the dispersal into the liquid for the bath may be carried out by any of the common mixing methods such as ball milling, cone milling, mechanical agitation and the like. It is also convenient in some cases merely to stir the powders or pigments directly into the carrier liquid.
  • Figs. 1, 2, 3, 4, 5 and 6 show static forms of apparatus used in the process
  • Figs. 7, 8, 9 and 10 show the process applied in apparatus suitable in continuous operation, that is with moving elements.
  • Fig. 1 shOWS the simplest method of practising the invention.
  • the particles 1, comprising solids, emulsions, emulsoids, colloids, or large molecules are suspended, dispersed or dissolved in the liquid 2 by conventional means such as is used in paint or ink manufacture, for example milling or grinding.
  • the liquid 2 is a liquid, or mixture of liquids, of relatively high volume resistivity, and is held in an insulating vessel 3.
  • the electrodes 4 and are immersed in the dispersion liquid 2 at an appropriate distance from each other depending on the voltage which is subsequently applied between them, but greater than that at which arcing will occur.
  • Such a voltage might normally be from 500 to 100,000 volts, and for 15,000 volts where the liquid is carbon tetrachloride for rapid deposition the distance would be about one inch.
  • the particles or droplets or molecules 1 are caused to be rejected by the electrode 4 to travel across the cell through the liquid 2 and deposit or adhere to the electrode 5 and retained on the electrode. With the above conditions a substantial coating is achieved in two seconds. Very thick deposits may be built up on the electrode 5 and retained if the field is maintained while the electrode 5 is removed from the vessel 3.
  • Fig. 2 shows another embodiment of the invention in which a third member or electrode 6 is interposed between two fixed electrodes 4 and 5, the electrode 6 being earthed through a high or low resistance.
  • the removable member or electrode 6, which may be a relative insulator such as a fiat paper, or a conductive metal sheet, is caused to receive the coating or deposit from the bath when the electrical field is set up between the electrodes 4 and 5.
  • the electrode or member 6 may also be caused to retain a thick deposit if removed whilst the field is maintained.
  • Fig. 3 shows another embodiment of the invention in which the vessel 3 is identical with the electrode 4, in this case for purposes of illustration a flat metal dish, but may be of other shape.
  • the object to be coated is identical with the electrode 5, being a flat object for the purpose of illustration. Deposition occurs primarily on the underside of the fiat electrode 5, and if the coating is itself an insulator deposition may subsequently also occur on the top of fiat electrode 5.
  • Fig. 4 shows an embodiment of the invention in which the object to be coated is one of irregular shape which it is desired to coat in its entirety.
  • the object 5 is first maintained at negative polarity for a selected period and deposition occurs predominantly on those areas 7 facing the positive electrode 4 and is hindered to a certain extend in re-entrant positions and at sharp edges the deposition is greater.
  • deposition occurs predominantly on those areas 8 opposite to the negative electrode 4.
  • the object is coated uniformly over the entire surface. It should be noted that the process is not designed for alternating currents of the order of fifty or more cycles per second as stringing of the particles tends to occur and deposition stops. Slow alternations of direct current of the order of one cycle per second or less than one per second are necessary, for about two to ten cycles, the uniform coating then being the result of relative potentials on varying parts of the object.
  • Another object identical or similar in shape to the object 5 can be substituted for the electrode 4 or be identical with the electrode 4, enabling two objects to be coated at once.
  • Fig. 5 shows an embodiment of the invention in which it is desired to coat a large object of irregular shape by immersion in a vessel.
  • the object 5, identical with the electrode 5, is immersed in the liquid 2 contained in the vessel 3, which is identical with the electrode 4.
  • To ensure uniformity of coating it may be necessary to include 4 removable additional electrodes 4a.
  • the liquid is drained away through outlet 9 whilst the field is maintained, or alternatively the electrodes 4a are lifted away and the object removed whilst the field is maintained or if the concentration of solids and the like in the suspen sion is selected suitably, the field need not be maintained.
  • Fig. 6 shows another method for practising the invention where it is desired to coat the inside of a hollow object.
  • the object 3 is the container for the liquid 2 and the particles 1 and is the one electrode.
  • the electrode 4, which may be shaped to conform with the inside of the object 3, is immersed in the liquid 2 and held in a fixed position to prevent it moving under the influence of the electrical field which is subsequently applied between 4 and 3. Deposition of the material occurs on the inside of the object 3 and added uniformity may be secured by cycling the polarity as in the manner of Fig. 4.
  • Fig. 7 shows an electrode 4 carrying the object 10 which is to be coated, and the coating substance 1 and carrier liquid 2 are carried by an absorbent roller 11 forming the other electrode 5. This roller 11 is moved across the surface of the object 10 to be coated and discharges coating material uniformly because of the electrostatic field.
  • Fig. 8 shows an embodiment of the invention in which the object 10 to be coated is continuously coated whilst the object is moving.
  • the object 10 which may be a web of paper or a metal foil or other flexible material, is arranged to pass through the liquid 2 and between the electrodes 4 and 5, preferably in contact with the electrode 5 as shown, and as it passes the coating 7 is caused to be deposited on it by the applied electrical field beween the two electrodes 4 and 5.
  • the vessel 3 may be made of an insulating material, or lined with an insulating material, but is shown identical with the electrode 4.
  • the voltage applied between the electrodes governs the distance between the electrodes, but is commonly set at 15,000 volts and one and a quarter inches respectively.
  • Fig. 9 shows an embodiment of the invention in which the object 10 to be coated is once again a web which it is desired to coat continuously.
  • a roller 11 which is identical with the electrode 5 and similarly placed but arranged to rotate or be driven at a uniform speed. Deposition occurs in a similar way to Fig. 8 except that the electrical field is less concentrated at the base of the electrode as will be apparent from the drawing.
  • the container 3 is shown as formed of an insulating material and the electrode 4 extends across it parallel to the roller 11 which forms the other electrode 5.
  • Fig. 10 shows apparatus designed to incorporate the principles set out for Figs. 8 and 9; in this case there is illustrated the roller system of Fig. 9, together with an arrangement to guide the web in and out of the bath 3, comprising the rollers 12 and 13.
  • the web is fed from the feed roller 14, over the guide rollers 12 into the baths 3 and then up and over the roller 13, through a drying tunnel 15 and on to the finish roller 16.
  • this arrangement merely demonstrates the principle and that other arrangements are possible which include other web treatment rollers and positions.
  • the object 10 passes through two separate containers 3-3, each with its electrodes 4, the containers 33 forming the other electrode 5.
  • the electrodes 4 could be arranged to produce lines of ditferent colour by adjusting their width and position in relation to the object 10, or could deposit difierent substances such as an adhesive and a granular material respectively or a base coat and a photo-sensitive coating respectively.
  • Beckosol P-786-50 and Nuodex are trade marks respectively for epoxy ester resin and cobalt naphthenate.
  • EXAMPLE 2 A paint composition of the following proportions dispersed in the liquid carbon tetrachloride:
  • Afiter mixing the above paste is dispersed in 100 grams of a halogenated hydrocarbon such as carbon tetrachloride and becomes the material for the bath.
  • the coating so obtained on the object after a short drying time comprises the pigments, the resins and the driers; polymerisation and hardening occurs after deposition.
  • EXAMPLE 3 A composition of the following proportions for dispersion in the liquid carbon tetrachloride designed to give a non-permanent coating for such purposes as carbon paper:
  • EXAMPLE 4 A composition of the following type for slow drying purposes:
  • EXAMPLE 5 A composition of the following proportions for dispersal in toluene and carbon tetrachloride for use in the coating of tapes for tape recorders:
  • EXAMPLE 6 A composition of the following proportions for dispersal in toluene for use in the coating of material in the form of thin transparent films:
  • This material is mixed with toluene and is immediately ready for use.
  • EXAMPLE 8 Carnauba Wax or beeswax dispersed in solvent naphtha to suitable consistency.
  • the function of the toluidine red, Zinc oxide, yellow litharge, carbon black, waxoline nigrosine and cadmium sclenide is as a colour material
  • Beckosol, Rhodene L9/50 are relatively permanent fixing agents.
  • the castor oil, linseed oil and carnauba wax or beeswax are fixing agents of a less permanent type, and act also as control agents, these substances when used with the more permanent fixing agents, serving to modify the permanence of the fixing agent as well as modifying the charge of the particles.
  • the permanent fixing agents may also modify the charge of the particles.
  • cobalt Nuodex cobalt naphthenate
  • manganese naphthenate act as driers
  • toluene, Xylol and the like form the insulating liquid and suspending agent.
  • the invention can be applied to the treatment of many materials With a large number of coating substances, but some specific examples now follow:
  • (:1) Tape for tape recorders The invention has application to the coating of such substances or backings as the tape used in magnetic recording machines where it is necessary to coat one side of a tape with a thin film of iron oxide or the like, the advantages of this invention in effecting such a coating being that there is a selective effect which ensures that only the particles in the bath which have the correct characteristic for deposition will be deposited, and as there is a uniform distribution of the suspended particles in the bath, there is likewise a uniform distribution on the tape, it having been shown that impurities and pan ticles of other characteristics can be deposited on the other electrode.
  • a composition for the dispersal materiai is given in Example 5 and an apparatus for continuous coating of the tape is shown in Fig. 8.
  • (d) Coloured paper and coloured paper in pattern form The invention has application to the production of high quality low cost coloured paper, foil and the like for various purposes in the printing industry, manufacture of containers, decorations and the like, by the coating of paper web of desired quality and characteristics with coloured matter of controlled thickness.
  • a composition for use where a thick gloss finish is required is given in Example 1, also designed to give a red colour.
  • the colours may be mixed in the base composition or in the bath itself by addition of pigments and dyestuffs at the appropriate time, mixing being assisted by the electric fields which cause deposition. This mixing can be carried out during deposition to give pattern forms.
  • the thickness of the coating may be varied by varying the time of deposition, and in the case of the continuous coater, Figs.
  • Coating of abrasives on to paper and other backings The invention also has application to the coating of abrasives on to paper or other suitable backings.
  • abrasive particles for the pigments in the Examples 1 to 5, or by including other binding agents in the mixtures, these abrasives may be coated in a similar way and the properties of the coating may be made more or less permanent by control of the binding material and its amount in relation to the quantity of abrasive and by selection of binders of suitable hardening properties.
  • the cutting action of the abrasive material can be made more uniform than has been possible heretofore because of the inherent selective effect of the invention as regards type of material deposited and also its selective effect with respect to size of particle deposited.
  • Coating leather and the like It is clear that the invention can be used also for the application of coloured or decorative or protective coatings to leather and other natural sheet material as well as to fibrous materials of artificial origin such as fabrics made from wool or cotton or silk or plastic fibres or plastic sheeting.
  • the web as coated may itself be conductive or insulating and in the latter case it may be necessary in some instances to render the back of the material conductive or partially conductive by the application of gelatine, or silver chloride or the like prior to coating, if the electric field strength is not sufficiently high.
  • Apparatus suitable for coating is shown in Figs. 8, 9 and 10 and materials for coating are generally similar to those already described.
  • a coating material such as a plastic or resin or pigmented resin or chemical particle or powder that is resistant to the corrosive environment to which the object is subjected, together with a suitable binding material if necessary.
  • This coating is applied in a manner illustrated in Fig. 6 that is by using the drum as an electrode and inserting another electrode to form the active electrodes.
  • plastic films Another application of the invention relates to the deposition of plastic material such as resins for example alkyd resins on to a foil or web or other object from which it is subsequently removed to form itself a web or foil or film.
  • plastic material such as resins for example alkyd resins
  • the film may be made in a transparent, translucent or opaque form by the addition of suitable pigments and the like.
  • the film so deposited may be removed from the electrode in various ways, including in the case of a roller or plate electrode removal by peeling by means of the use of a knife or other peeling device.
  • the roller or web on which the film is deposited may be pre-treated with a material which renders it non-adherent to the deposited film although not impairing the deposition; consequently the film may be removed after deposition.
  • An example of this is pretreatment of the web or roller or plate with a water soluble glue or dextrin or the like.
  • Another means whereby the film may be removable is to deposit it on a liquid surface which is identical with or connected to the depositing electrode.
  • a liquid includes mercury metal, or water, or other conductive liquid.
  • roller it is possible to build up a firm resin-bonded pigmented layer up to a quarterinch thick or more, having a smooth resilient surface and character ideally suited for inking and offset rollers. It is obvious that the roller so formed may be re-worked after a period of service by machining oflt the top skin and re-coating by our method.
  • a printing platen can be built up by coating a flat metal or other surface plate. It will be appreciated also that if the metal backing is shaped to have high or low spots or areas or lines then the coating will follow and accentuate these spots, areas or lines.
  • type is first set, it is possible to coat the type-face thickly and afterwards remove the coating to form a matrix.
  • the web which is coated may be of fabric based on Wool, cotton, silk or plastic and the like and a layer of electrophotographic paint can be deposited on it.
  • This layer can subsequently be used to photograph patterns, scenes, landscapes, portraits and the like on to the fabric and the Zinc oxide or other electrophotographic pigment removed in the manner of a previous application of the present inventors.
  • the fabric may be of fine silk net such as is used in the manufacture of silk screens and this may be given an overall coating of electrophotographic paint which may be caused to take a. pattern and in the areas unprotected by a pattern the electrophotographic pigment may be dissolved away so that the Whole forms a stencil or mask in pattern form for painting purposes.
  • the electro-deposited coating may be arranged to have the properties of fluorescence, permanence, and smoothness necessary for close contact and proper action on an underlying silver halide or other film when used in conjunction with the (0) Transfer paper for electrophotography Proceeding as for item (0) but omitting the carbon pigment, a thin sticky film, more cohesive than adhesive may be deposited on a suitable backing such as white paper suitable for transfer of developed electrostatic images.
  • the permanent resin film may be used for the transfer of electrostatic images.
  • a process for coating a backing with a metal oxide comprising coating the metal oxide with an alkyd resin and forming a paste thereof with a drier and a carrier liquid, dispersing the paste in a halogenated hydrocarbon liquid, establishing an electrostatic field in said liquid, and placing the backing in said field in the liquid thereby depositing the metal oxide on the backing.
  • a process as claimed in claim 1 for providing magnetic tape wherein the metal oxide is iron oxide, the drier is a naphthenate, the carrier liquid is toluene, said backing is a tape, and the liquid is carbon tetrachloride.

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US663742A 1956-06-14 1957-06-05 Coating surfaces by employing an electrostatic field Expired - Lifetime US2898279A (en)

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AU19038/56A AU221527B2 (en) 1956-06-14 Method of and means for coating surfaces bye le ctro-deposition
AU2651357 1957-03-26

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BE (1) BE558297A (xx)
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Cited By (42)

* Cited by examiner, † Cited by third party
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US3064622A (en) * 1960-06-20 1962-11-20 Xerox Corp Immersion development
DE1141402B (de) * 1959-12-11 1962-12-20 Iashellia Res Ltd Schmierfett
US3076722A (en) * 1959-04-29 1963-02-05 Rca Corp Electrostatic printing
US3097961A (en) * 1958-09-26 1963-07-16 Saint Gobain Plastic coating of glass objects
US3102045A (en) * 1957-06-28 1963-08-27 Metcalfe Kenneth Archibald Production of patterns on cloth or similar substances
US3108893A (en) * 1958-11-07 1963-10-29 Australia Res Lab Applying printed patterns electrostatically
US3132927A (en) * 1961-07-31 1964-05-12 Int Nickel Co Wear-resistant material
US3145655A (en) * 1959-06-23 1964-08-25 Xerox Corp Equipotential xeroprinting member and process of printing therewith
US3155531A (en) * 1958-09-23 1964-11-03 Harris Intertype Corp Meagnetic liquid developer and method for electrostatic images
US3241998A (en) * 1960-07-12 1966-03-22 Australia Res Lab Method of fixing xerographic images
US3257304A (en) * 1961-11-27 1966-06-21 Minnesota Mining & Mfg Process of electrodepositing insulative material on photoconductive copysheet
US3283714A (en) * 1962-05-23 1966-11-08 Courtaulds Ltd Rollers carrying surface designs for use in printing, embossing and the like
US3366563A (en) * 1962-09-10 1968-01-30 Pittsburgh Plate Glass Co Electropainting process and paint compositions therefor
US3378477A (en) * 1962-02-27 1968-04-16 Goodlass Wall & Co Ltd Process for the deposition of resinous films on metal objects
US3381662A (en) * 1962-11-27 1968-05-07 Harris Intertype Corp Electrophotographic micro-copy printer
US3417003A (en) * 1966-02-21 1968-12-17 Sprague Electric Co Polymer deposit electrochemically
US3440160A (en) * 1966-02-09 1969-04-22 Pitney Bowes Inc Method and apparatus for controlling suspension concentrations
US3450655A (en) * 1965-04-09 1969-06-17 Ransburg Electro Coating Corp Non-aqueous suspension for electrophoretically coating articles comprising a pigment and an organic-solventsoluble thermosetting resin
US3462286A (en) * 1963-07-16 1969-08-19 Gevaert Photo Prod Nv Method of coating webs with photographic emulsions or other liquid compositions utilizing an electric field
US3463714A (en) * 1967-06-30 1969-08-26 Continental Can Co Electrodeposition of polymers in non-aqueous media
US3472676A (en) * 1965-11-18 1969-10-14 Gevaert Photo Prod Nv Process for developing electrostatic charge patterns
US3486922A (en) * 1967-05-29 1969-12-30 Agfa Gevaert Nv Development of electrostatic patterns with aqueous conductive developing liquid
US3502563A (en) * 1965-06-29 1970-03-24 Gen Electric Control of electrodeposits
US3511651A (en) * 1966-08-22 1970-05-12 Owens Illinois Inc Persistent internal polarization imaging system with electrophoretic development
US3622483A (en) * 1967-11-08 1971-11-23 Emi Ltd Electrical deposition of material
FR2083439A1 (xx) * 1970-03-20 1971-12-17 Yazaki Corp
US3640814A (en) * 1965-03-17 1972-02-08 Ashdee Corp Electrocoating apparatus
US3669859A (en) * 1969-08-29 1972-06-13 Eastman Kodak Co Process and compositions for protecting images with resin films
US3779748A (en) * 1971-08-11 1973-12-18 Eastman Kodak Co Method of protecting images
US3844919A (en) * 1969-06-10 1974-10-29 Ricoh Kk Method of preparing photosensitive surfaces
US3857549A (en) * 1968-02-23 1974-12-31 Xerox Corp Photoelectrophoretic imaging apparatus
US3892648A (en) * 1974-04-16 1975-07-01 Us Navy Electrochemical deposition of bone
US3892568A (en) * 1969-04-23 1975-07-01 Matsushita Electric Ind Co Ltd Electrophoretic image reproduction process
US3897326A (en) * 1974-08-16 1975-07-29 Us Health Education & Welfare Protein coated electrode
US4021586A (en) * 1970-10-08 1977-05-03 Canon Kabushiki Kaisha Method of and means for the development of electrostatic images
US4089765A (en) * 1973-12-14 1978-05-16 Canada Wire And Cable Limited Electroimpregnation of paper and non-woven fabrics
EP0037464A2 (en) * 1980-03-24 1981-10-14 International Business Machines Corporation Process for selectively reinking used thermal transfer printing ribbon and method for making a colloidal dispersion for use in said process
US5196098A (en) * 1988-01-04 1993-03-23 Shipley Company Inc. Apparatus and process for electrophoretic deposition
WO2018149483A1 (de) 2017-02-14 2018-08-23 August Rüggeberg Gmbh & Co. Kg Verfahren zur herstellung eines schleifwerkzeugs und schleifwerkzeug
CN108970612A (zh) * 2018-06-26 2018-12-11 西安理工大学 一种制备Ag负载ZnO纳米棒阵列的方法
US20220255187A1 (en) * 2021-02-10 2022-08-11 GM Global Technology Operations LLC Method for coating a separator for a battery
CN114986405A (zh) * 2022-06-28 2022-09-02 泰科材料技术(广州)有限公司 一种超细磨料颗粒有序排布方法

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3417019A (en) * 1962-12-27 1968-12-17 Eastman Kodak Co Xerographic development
US3481839A (en) * 1963-10-21 1969-12-02 Inoue K Method of depositing substances on and diffusing them into conductive bodies under high-frequency electric field
JPS6023830A (ja) * 1983-07-19 1985-02-06 Seiko Instr & Electronics Ltd カラー表示装置およびその製造方法
JPS6023834A (ja) * 1983-07-19 1985-02-06 Seiko Instr & Electronics Ltd マトリクス型多色表示装置用基板の製造方法
JPS60188927A (ja) * 1984-03-08 1985-09-26 Toshiba Corp カラ−・マトリツクス型液晶表示装置の製造方法
DE8511549U1 (de) * 1985-04-18 1986-06-19 Ferd. Rüesch AG, St. Gallen Siebdruckschablone

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GB291477A (en) * 1926-12-03 1928-06-05 Dunlop Rubber Co Process for the manufacture of articles from synthetic resins or shellac
GB369382A (en) * 1930-03-12 1932-03-24 Gen Electric Improvements in and relating to methods of applying insulating coatings of varnish
US1884110A (en) * 1929-04-15 1932-10-25 Rca Corp Electroplating of wax
US1899016A (en) * 1927-10-28 1933-02-28 American Anode Inc Dehydrating rubber deposited from aqueous dispersions
GB482548A (en) * 1936-04-01 1938-03-31 British Thomson Houston Co Ltd Improvements in the electric deposition of resin films
US2215143A (en) * 1935-07-06 1940-09-17 Crosse And Blackwell Ltd Lacquered metal container for foodstuffs
US2214876A (en) * 1936-04-14 1940-09-17 Gen Electric Method of fabricating electrolytic capacitor
US2337972A (en) * 1938-06-29 1943-12-28 Crosse & Blackwell Ltd Process of coating metals
FR1020434A (fr) * 1950-06-14 1953-02-06 Thomson Houston Comp Francaise Préparation des revêtements à émission électronique élevée
US2800448A (en) * 1954-04-30 1957-07-23 Rca Corp Cataphoretic coating machine

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB291477A (en) * 1926-12-03 1928-06-05 Dunlop Rubber Co Process for the manufacture of articles from synthetic resins or shellac
US1899016A (en) * 1927-10-28 1933-02-28 American Anode Inc Dehydrating rubber deposited from aqueous dispersions
US1884110A (en) * 1929-04-15 1932-10-25 Rca Corp Electroplating of wax
GB369382A (en) * 1930-03-12 1932-03-24 Gen Electric Improvements in and relating to methods of applying insulating coatings of varnish
US2215143A (en) * 1935-07-06 1940-09-17 Crosse And Blackwell Ltd Lacquered metal container for foodstuffs
GB482548A (en) * 1936-04-01 1938-03-31 British Thomson Houston Co Ltd Improvements in the electric deposition of resin films
US2214876A (en) * 1936-04-14 1940-09-17 Gen Electric Method of fabricating electrolytic capacitor
US2337972A (en) * 1938-06-29 1943-12-28 Crosse & Blackwell Ltd Process of coating metals
FR1020434A (fr) * 1950-06-14 1953-02-06 Thomson Houston Comp Francaise Préparation des revêtements à émission électronique élevée
US2800448A (en) * 1954-04-30 1957-07-23 Rca Corp Cataphoretic coating machine

Cited By (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3102045A (en) * 1957-06-28 1963-08-27 Metcalfe Kenneth Archibald Production of patterns on cloth or similar substances
US3155531A (en) * 1958-09-23 1964-11-03 Harris Intertype Corp Meagnetic liquid developer and method for electrostatic images
US3097961A (en) * 1958-09-26 1963-07-16 Saint Gobain Plastic coating of glass objects
US3108893A (en) * 1958-11-07 1963-10-29 Australia Res Lab Applying printed patterns electrostatically
US3076722A (en) * 1959-04-29 1963-02-05 Rca Corp Electrostatic printing
US3145655A (en) * 1959-06-23 1964-08-25 Xerox Corp Equipotential xeroprinting member and process of printing therewith
DE1141402B (de) * 1959-12-11 1962-12-20 Iashellia Res Ltd Schmierfett
US3064622A (en) * 1960-06-20 1962-11-20 Xerox Corp Immersion development
US3241998A (en) * 1960-07-12 1966-03-22 Australia Res Lab Method of fixing xerographic images
US3132927A (en) * 1961-07-31 1964-05-12 Int Nickel Co Wear-resistant material
US3257304A (en) * 1961-11-27 1966-06-21 Minnesota Mining & Mfg Process of electrodepositing insulative material on photoconductive copysheet
US3378477A (en) * 1962-02-27 1968-04-16 Goodlass Wall & Co Ltd Process for the deposition of resinous films on metal objects
US3283714A (en) * 1962-05-23 1966-11-08 Courtaulds Ltd Rollers carrying surface designs for use in printing, embossing and the like
US3366563A (en) * 1962-09-10 1968-01-30 Pittsburgh Plate Glass Co Electropainting process and paint compositions therefor
US3381662A (en) * 1962-11-27 1968-05-07 Harris Intertype Corp Electrophotographic micro-copy printer
US3462286A (en) * 1963-07-16 1969-08-19 Gevaert Photo Prod Nv Method of coating webs with photographic emulsions or other liquid compositions utilizing an electric field
US3640814A (en) * 1965-03-17 1972-02-08 Ashdee Corp Electrocoating apparatus
US3450655A (en) * 1965-04-09 1969-06-17 Ransburg Electro Coating Corp Non-aqueous suspension for electrophoretically coating articles comprising a pigment and an organic-solventsoluble thermosetting resin
US3502563A (en) * 1965-06-29 1970-03-24 Gen Electric Control of electrodeposits
US3472676A (en) * 1965-11-18 1969-10-14 Gevaert Photo Prod Nv Process for developing electrostatic charge patterns
US3440160A (en) * 1966-02-09 1969-04-22 Pitney Bowes Inc Method and apparatus for controlling suspension concentrations
US3417003A (en) * 1966-02-21 1968-12-17 Sprague Electric Co Polymer deposit electrochemically
US3511651A (en) * 1966-08-22 1970-05-12 Owens Illinois Inc Persistent internal polarization imaging system with electrophoretic development
US3486922A (en) * 1967-05-29 1969-12-30 Agfa Gevaert Nv Development of electrostatic patterns with aqueous conductive developing liquid
US3463714A (en) * 1967-06-30 1969-08-26 Continental Can Co Electrodeposition of polymers in non-aqueous media
US3622483A (en) * 1967-11-08 1971-11-23 Emi Ltd Electrical deposition of material
US3857549A (en) * 1968-02-23 1974-12-31 Xerox Corp Photoelectrophoretic imaging apparatus
US3892568A (en) * 1969-04-23 1975-07-01 Matsushita Electric Ind Co Ltd Electrophoretic image reproduction process
US3844919A (en) * 1969-06-10 1974-10-29 Ricoh Kk Method of preparing photosensitive surfaces
US3669859A (en) * 1969-08-29 1972-06-13 Eastman Kodak Co Process and compositions for protecting images with resin films
FR2083439A1 (xx) * 1970-03-20 1971-12-17 Yazaki Corp
US4021586A (en) * 1970-10-08 1977-05-03 Canon Kabushiki Kaisha Method of and means for the development of electrostatic images
US3779748A (en) * 1971-08-11 1973-12-18 Eastman Kodak Co Method of protecting images
US4089765A (en) * 1973-12-14 1978-05-16 Canada Wire And Cable Limited Electroimpregnation of paper and non-woven fabrics
US3892648A (en) * 1974-04-16 1975-07-01 Us Navy Electrochemical deposition of bone
US3897326A (en) * 1974-08-16 1975-07-29 Us Health Education & Welfare Protein coated electrode
EP0037464A2 (en) * 1980-03-24 1981-10-14 International Business Machines Corporation Process for selectively reinking used thermal transfer printing ribbon and method for making a colloidal dispersion for use in said process
EP0037464A3 (en) * 1980-03-24 1982-05-05 International Business Machines Corporation Process for selectively reinking used thermal transfer printing ribbon and method for making a colloidal dispersion for use in said process
US5196098A (en) * 1988-01-04 1993-03-23 Shipley Company Inc. Apparatus and process for electrophoretic deposition
WO2018149483A1 (de) 2017-02-14 2018-08-23 August Rüggeberg Gmbh & Co. Kg Verfahren zur herstellung eines schleifwerkzeugs und schleifwerkzeug
US11518002B2 (en) 2017-02-14 2022-12-06 Pferd Milwaukee Brush Company, Inc. Method for producing a grinding tool and grinding tool
EP3397429B1 (de) * 2017-02-14 2023-07-19 August Rüggeberg GmbH & Co. KG Verfahren zur herstellung eines schleifwerkzeugs
CN108970612A (zh) * 2018-06-26 2018-12-11 西安理工大学 一种制备Ag负载ZnO纳米棒阵列的方法
CN108970612B (zh) * 2018-06-26 2021-01-15 西安理工大学 一种制备Ag负载ZnO纳米棒阵列的方法
US20220255187A1 (en) * 2021-02-10 2022-08-11 GM Global Technology Operations LLC Method for coating a separator for a battery
CN114904741A (zh) * 2021-02-10 2022-08-16 通用汽车环球科技运作有限责任公司 用于涂覆电池组的隔离件的方法
US11424509B1 (en) * 2021-02-10 2022-08-23 GM Global Technology Operations LLC Method for coating a separator for a battery
CN114986405A (zh) * 2022-06-28 2022-09-02 泰科材料技术(广州)有限公司 一种超细磨料颗粒有序排布方法
CN114986405B (zh) * 2022-06-28 2023-10-24 泰科材料技术(广州)有限公司 一种超细磨料颗粒有序排布方法

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NL218099A (xx)
CH358721A (fr) 1961-11-30
NL111927C (xx)
DE1446720A1 (de) 1975-02-06
GB866780A (en) 1961-05-03
BE558297A (xx)

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