US3730753A - Method for treating a web - Google Patents

Method for treating a web Download PDF

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Publication number
US3730753A
US3730753A US00167758A US3730753DA US3730753A US 3730753 A US3730753 A US 3730753A US 00167758 A US00167758 A US 00167758A US 3730753D A US3730753D A US 3730753DA US 3730753 A US3730753 A US 3730753A
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United States
Prior art keywords
charge
web
corona
amount
coating
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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
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US00167758A
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English (en)
Inventor
W Kerr
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.)
Eastman Kodak Co
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Eastman Kodak Co
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Filing date
Publication date
Application filed by Eastman Kodak Co filed Critical Eastman Kodak Co
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Publication of US3730753A publication Critical patent/US3730753A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C59/00—Surface shaping of articles, e.g. embossing; Apparatus therefor
    • B29C59/10—Surface shaping of articles, e.g. embossing; Apparatus therefor by electric discharge treatment
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05F—STATIC ELECTRICITY; NATURALLY-OCCURRING ELECTRICITY
    • H05F3/00—Carrying-off electrostatic charges
    • H05F3/04—Carrying-off electrostatic charges by means of spark gaps or other discharge devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
    • B29K2995/0003—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds having particular electrical or magnetic properties, e.g. piezoelectric
    • B29K2995/001—Electrostatic

Definitions

  • the improved method employs the technique of flooding the surface with charge of a first polarity so as to generally uniformly charge the surface and thereafter removing the charge imparted to the surface, so as to leave the surface generally free of charge.
  • the invention provides the improvement of monitoring the surface of the web for charge variation and for net charge.
  • the amount of charge added to and/or the amount of charge removed from the surface may be so controlled that the charge variation and the net charge on the surface is lowered to an acceptable level, preferably approximately zero.
  • This invention relates to the treatment of webs. More particularly, the invention relates to a method for treating a web so as to improve the webs coatability.
  • a web of photographic paper may be polyethylene-coated; and such coating may be coronatreated before the application of a photographic emulsion thereon.
  • corona-treatment of the polyethylene surface may enhance the receptivity of the surface to the emulsion, a problem arises in that corona-treatment of the surface usually leaves a non-uniform distribution of, i.e., a pattern of, electrostatic charge on the surface.
  • this charge pattern In coating systems where the coating operation is delicate, i.e., easily disturbed, this charge pattern must be substantially removed before the web is introduced into the coating station, if uniform coatings are to be produced. Otherwise, the charge pattern will cause coating bead disturbances and thus cause the coating to be uneven.
  • the alternating electric field created by the corona-producing means distributes charged particles of different polarities onto the surface in a non-uniform charge pattern.
  • hills comprising a relatively large amount of positive charge, and adjacent thereto valleys of a relatively large amount of negative charge.
  • the emulsion coating is deposited on the web, it is afiected by the surface charge distribution, and in a sense the emulsion aligns with the charge pattern and forms what has been called crosslines, thus adversely affecting the photographic quality of the product in question.
  • charge may be comprised of two types:
  • the first roller applies, say, a large amount of positive charge to the face side of the web and induces its counter electrode to deposit an equal amount of negative charge onto the wire side of the web.
  • the application of negative charge is able to neutralize the polar positive charge on the wire side, and thereby frees the polar negative charge on the face side which may then be either conducted away or neutralized by the positively charged roller.
  • the web is then conveyed to a second charging station comprising a relatively negatively charged roller and its relatively positively charged counter electrode. At this point, positively charged particles are applied to the wire side of the web to neutralize the negative charge, thereby freeing the positive charge on the face side which may then be removed by the relatively negatively charged roller.
  • the amount of charge applied to each surface at the second charging station is equal to the amount of charge of opposite polarity applied to each surface at the first charging station.
  • a web having a relatively conductive layer either as an external surface layer or a layer sandwiched by other layers, a problem arises in balancing the amount of charge that is applied to the web at the charging stations.
  • the conductive layer which may be grounded through various rollers-causes the first roller to see or be exposed to ground and, as a result, some charge may leak to ground, causing the first roller to deposit more charge on the web than the second roller removes.
  • the invention provides an improved method for use in applying a coating to a corona-treated web surface.
  • the invention employs the technique of substantially removing non-uniform charge patterns from the surface by flooding the web with charge of a first polarity and thereafter removing the charge from the web and improves over such technique, among other things, by sensing the web surface for net charge and charge variation so that the amount of charge flooded onto the surface may be assuredly or positively controlled relative to the amount of charge removed.
  • An object of the invention is to provide an improved method for treating a web surface to enhance the surfaces coatability.
  • Another object of the invention is to provide an improved method for removing charge patterns from a web surface for enhancing the surfaces coatability.
  • FIG. 1 there is shown a representation of one apparatus for carrying out the improved method fully described herein.
  • FIGS. 2 and 3 there are shown alternate embodiments for a portion of the apparatus of FIG. 1.
  • Zone 1 a coating apparatus is shown wherein a web of dielectric material or one having a dielectric coating is conveyed from an unwind station 13 to a corona-treatment station 15, hereafter referred to as Zone 1.
  • dielectric refers to any surface with a surface resistivity of about 10 ohms per square or greater.
  • the web 10 is conveyed about an electrically grounded metal roller 17 so that one web surface 12, is in intimate contact with the surface of the roller.
  • alternating-current corona-treatment On the opposite side of the web, web surface 11 is exposed to a conventional alternatingcurrent corona-treatment, so as to enhance its receptivity to a coating, such as, for example, inks, adhesives, photographic emulsions, subbing layers, etc.
  • a glow of corona may be seen to extend from electrodes 21, 23, and 25 to the surface 11.
  • the electrodes may be connected to a suitable alternating-current power supply 31 for providing a suitable level of potential for ionizing the air between the electrodes and the surface.
  • alternating-currents and voltages are any such currents and voltages which vary, such, for example, as sinusoidal and pulsating currents and voltages. If desired, provision may be made in Zone 1 for corona-treating web surface 12.
  • the dielectric surface becomes highly charged with charge that is, as indicated in the drawing, non-uniformly distributed along the surface 11.
  • this charge which may be comprised of both polar and free charges
  • the web is conveyed to Zone 2.
  • the web 10 is wrapped about an electrically swu sd m a ro ler 2.7 with he W ar a s 12 in intimate contact with the conductive surface of the roller.
  • the web surface 11 is exposed to negatively charged electrodes 29, 30 which flood a large amount of negatively charged particles onto the corona-treated surface.
  • the electrodes may be electrically connected to the negative terminal of an adjustable 020,000 volt, 02 ma., source 33 of DC potential.
  • the grounded roller 27 acts as a counter electrode for the electrodes 29, 30 and deposits a high positive charge onto the web surface 12.
  • Electrodes 37, 39 which may be electrically connected to the positive terminal of an adjustable 0- 20,000 volt, 0-2 ma., source 35 of DC potential.
  • the elec trodes 37, 39 deposit a large amount of positively charged particles onto the web surface 11 to neutralize the negative charge previously imparted to the surface 11.
  • the grounded roller 27 at this point functions as a counter electrode for the electrodes 37, 39; and as a source of negative potential, the roller neutralizes the positive charge on web surface 12.
  • a grounded electrode 41 may be positioned adjacent the web surface at a point where the web is no longer in contact with the grounded roller 27.
  • Such a position may be just prior to the webs being conveyed about one of the grounded conveyance rollers 43. It should be appreciated that in Zone 2, no corona-treatment of the web need occur, nor is desirable. While a corona glow may appear in the vicinity of the electrodes 29, 30 and 37, 39, such glow need not extend to the surface 11, as it would during conventional corona-treatment processes.
  • the web is conveyed about the ground ed roller 51 so that the web surface 12 is in intimate contact with the roller, the web surface 11 being exposed to an induction probe 53 of a fieldmeter.
  • the probe 53 is electrically connected to the Input terminal of an electrometer 57, which amplifies the signal induced in the probe 53 by the charge on the web surface 11 and indicates the DC potential (i.e., net charge) of the surface 11.
  • an AC voltmeter 59 Connected to the Output terminal of the electrometer 57 is an AC voltmeter 59 which is capable of detecting a high frequency, i.e., AC components of, the potential on the surface 11, thereby to indicate that a variation in charge is present on the surface 11.
  • both sources 33 and 35 are not charging the web surface 11 to the extent necessary to eliminate the hills and valleys of charge imparted to surface 11 in Zone 1.
  • the AC voltmeter will indicate zero or nearzero voltage.
  • the potentials of the sources 33 and 35 may be relatively varied to remove the uniform level of charge which may exist on the web.
  • the electrometer 57 may be used to detect this uniform charge of DC potential and will also indicate its polarity. To reduce the uniform level of charge on the web surface 11, one need only adjust the sources 33, 35 until the electrometer indicates a zero or near-zero charge level.
  • a coating hopper 63 Downstream of the probe 53 is a coating hopper 63 for applying a coating 65 such as a photographic emulsionto the web surface 11.
  • a coating 65 such as a photographic emulsionto the web surface 11.
  • the tolerable potential levels on the web surface 11 are preferably 50 volts DC and 50 volts AC, but there are instanceswhere higher potentials, say, volts AC and DC may be tolerated. In certain instances, potentials, say, of 20 volts AC and DC, may be required.
  • the grounded-roller counter electrode 27 may, if desired, be replaced by grounded electrodes 81, 82 (FIG. 2) or by electrodes 83, 84 (FIG. 3) that are connected to DC potential sources 85, 86, respectively.
  • the alternate embodiments shown in FIGS. 2 and 3 can function in a manner which is similar to that described above for the operation of the Zone 2 apparatus of FIG. 1.
  • modifications may include the use of two probes, i.e., one placed adjacent the web between sources 33 and 35 and connected to an AC sensitive device, and the other placed as shown in FIG. 1 but connected to just a DC sensitive device.
  • the detection of an AC signal by the AC sensitive device may be considered an indication that the source 33 is not charging the web surface 11 to the extent necessary to remove the non-uniform charge pattern.
  • the invention in its broader aspects is not linked to particular web compositions nor to particular coatings to be placed thereon.
  • the method for carrying out the invention may be quite useful in the treatment of webs comprised of films and surfaces of various materials, including polyolefins such as polyethylenes, polypropylenes, and ethylene-propylene copolymers, polystyrene, polybutenes, polypentenes, polyacrylic acid esters,
  • linear polyesters and polycarbonates such as polyethylene terephthalates, polyamides such as nylon, cellulose esters, polyacrylonitrile, polyvinylidene chloride and other copolymers of the indicated monomers, such as ethylenevinyl acetate copolymers.
  • Coatings, other than the preferred light-sensitive silver halide gelatin emulsions may be placed on the web.
  • non-light-sensitive gelatin emulsions, as well as other compositions which may be coated by a hopper such as coatings including magnetic oxides, organic solvents, etc., may be coated in accordance with the invention described herein.
  • the particular charge sensing devices are th'e preferred ones; however, other sensing devices may be used to either supplement or replace the preferred ones.
  • an oscilloscope may be added to or substituted for the AC or DC sensitive devices disclosed.
  • a slow-responding chart recorder may be used in conjunction with or as a replacement for the electrometer 57.
  • a process for the preparation of a surface of a web for deposition of a coating on the surface including an initial non-uniform distribution of electric charge that is to be substantially removed from the surface prior to deposition of the coating thereon, the process including the steps of:
  • step (c) sensing the net charge and the charge variation on the surface and relatively adjusting the amount of charge applies in step (a) and the amount of charge removed in step (b) so that the charge variation and the net charge on the surface are substantially reduced.
  • step (c) charge variation is sensed by sensing the alternating current potential on the surface after the surface has been treated in accordance with at least step (a).
  • step (0) net charge is sensed by sensing the direct current potential on the surface after the surface has been treated in accordance with at least steps (a) and (b).
  • steps (a) and (b) charge is being applied to and removed from the surface without corona-treating the surface.
  • step (a) charge of said first polarity is applied to said surface from a first DC potential charging means and in step (b) charge of opposite polarity to that of said first polarity is deposited from a second DC potential charging means to remove the charge applied in step (a).
  • step (b) depositing onto said surface after it has been treated in accordance with step (a) charge of a second polarity opposite in polarity to that applied in step (a) from a second DC potential charging means, which second charging means is adapted to deposit a sufficient amount of said charge of a second polarity to remove the charge applied to said surface in step (a), and the improvment which comprises;
  • step (c) sensing the net charge on said surface after said surface has been treated in accordance with steps (a) and (b), and sensing the charge variation on said surface after said surface has been treated in accordance with at least step (a); and relatively adjusting the charging of and the removal of charge from said surface in steps (a) and (b) so that the charge variation on the surface is substantially removed and the net charge on the surface is substantially reduced.
  • step (c) charge variation is sensed by sensing the alternating current potential on the surface and net charge is sensed by sensing the direct current potential on said surface.
  • a process for coating a surface of a web comprises the steps of (a) corona-treating the surface; and then (b) applying electric charge of a first polarity to the surface; and then (c) removing charge from the surface;
  • step (e) sensing, prior to step (d), the net charge on the surface after the surface has been treated in accordance with steps (b) and (c), and sensing, prior to step (d), the charge variation on the surface after the surface has been treated in accordance with at least step (b); and relatively adjusting the amount of charge applied to and the amount of charge removed from the surface in steps (b) and (c) so that the charge ,variation on the surface is substantially removed and the net charge on the surface is substantially reduced.
  • step (d) the coating is delivered to the surface by a hopper.
  • step (e) charge variation is sensed by sensing the alternating current potential on the surface and net charge is sensed by sensing the direct-current potential on the surface.
  • a process for coating a dielectric surface of a web which process comprises the steps of:
  • step (e) sensing, prior to step (d), the net charge on the surface to be coated after the surface to be coated has been treated in accordance with steps (b) and (c), and sensing, prior to step (d), the charge variation on the surface to be coated after the surface to be coated has been treated in accordance with at least step (b); and relatively adjusting the charging of and the removal of charge from the surface to be coated in steps (b) and (0) so that the charge variation on the surface to be coated is substantially removed and the net charge on the surface to be coated is substantially reduced.
  • step (e) charge variation is sensed by sensing the alternating current potential on the surface and net charge is sensed by sensing the direct-current potential on the surface.
  • step (d) the coating is delivered to the surface by a hopper.

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  • Treatments Of Macromolecular Shaped Articles (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Elimination Of Static Electricity (AREA)
US00167758A 1971-07-30 1971-07-30 Method for treating a web Expired - Lifetime US3730753A (en)

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US16775871A 1971-07-30 1971-07-30

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US (1) US3730753A (de)
JP (1) JPS4825071A (de)
AU (1) AU4509272A (de)
BE (1) BE786484A (de)
BR (1) BR7205054D0 (de)
CA (1) CA978499A (de)
DE (1) DE2237282B2 (de)
FR (1) FR2147997B1 (de)

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3865480A (en) * 1973-12-20 1975-02-11 Xerox Corp Electrostatic control of fan fold paper stacking
US3892614A (en) * 1973-03-08 1975-07-01 Simco Co Inc Electrostatic laminating apparatus and method
US3916063A (en) * 1973-10-11 1975-10-28 Thilmany Pulp & Paper Company Method for manufacturing a printable, glueable polyolefin web material
US4055685A (en) * 1975-04-30 1977-10-25 Agfa-Gevaert Aktiengesellschaft Process for the improvement of the adhesion of photographic layers to a film web by means of a corona treatment
US4216254A (en) * 1979-05-05 1980-08-05 Union Carbide Corporation Method of selectively treating a plastic film surface to prevent blocking
US4233562A (en) * 1978-11-08 1980-11-11 Imperial Chemical Industries Limited Apparatus and method for monitoring web conductivity
US4271451A (en) * 1976-07-20 1981-06-02 Hercules Incorporated Method and apparatus for controlling static charges
US4486808A (en) * 1982-12-03 1984-12-04 Polaroid Corporation Apparatus for controlling random charges on a moving web
EP0136606A2 (de) * 1983-10-03 1985-04-10 Polaroid Corporation Verfahren und Geräte zur gleichförmigen Aufladung einer bewegten Bahn
US4743258A (en) * 1984-04-27 1988-05-10 Japan Medical Supply Co., Ltd. Polymer materials for vascular prostheses
US4780680A (en) * 1984-11-03 1988-10-25 Hoechst Aktiengesellschaft Process for the continuous, contact-free measurement of layer thicknesses and apparatus for performing the process
US4810432A (en) * 1987-12-28 1989-03-07 Polaroid Corporation Method and apparatus for establishing a uniform charge on a substrate
US5805407A (en) * 1995-09-07 1998-09-08 Fuji Photo Film Co., Ltd. Charge eliminating apparatus for a moving web
US6171658B1 (en) * 1998-02-06 2001-01-09 Eastman Kodak Company Coating method using electrostatic assist
US6312767B2 (en) * 1997-11-05 2001-11-06 L'air Liquide, Societe Anonyme Pour L'exploitation Des Procedes Georges Claude Process and device for the surface treatment of a substrate by an electrical discharge between two electrodes in a gas mixture
US6368675B1 (en) 2000-04-06 2002-04-09 3M Innovative Properties Company Electrostatically assisted coating method and apparatus with focused electrode field
US6475572B2 (en) 2000-04-06 2002-11-05 3M Innovative Properties Company Electrostatically assisted coating method with focused web-borne charges
US6517909B1 (en) * 1998-12-16 2003-02-11 Eastman Kodak Company Method for using a patterned backing roller for curtain coating a liquid composition to a web
US20040072664A1 (en) * 2001-02-14 2004-04-15 Mario Spatafora Method and a device for checking wrapping material in a packaging machine
US20040085705A1 (en) * 2002-10-30 2004-05-06 Zaretsky Mark C. Electrostatic charge neutralization using grooved roller surface patterns
US6745001B2 (en) 2002-05-06 2004-06-01 Nexpress Solutions Llc Web conditioning charging station
WO2009002665A1 (en) * 2007-06-22 2008-12-31 3M Innovative Properties Company Apparatus and methods for modification of electrostatic charge on a moving web
US20090009922A1 (en) * 2005-01-28 2009-01-08 Toray Industries, Inc. Electric-insulating sheet neutralizing device, neturalizing method and production method
WO2009085751A1 (en) * 2007-12-21 2009-07-09 3M Innovative Properties Company Apparatus and methods for altering charge on a dielectric material
WO2012054316A1 (en) 2010-10-21 2012-04-26 Eastman Kodak Company Concurrently removing sheet charge and curl
US8320817B2 (en) 2010-08-18 2012-11-27 Eastman Kodak Company Charge removal from a sheet
TWI406811B (zh) * 2010-02-03 2013-09-01 Beijing Funate Innovation Tech 奈米碳管膜之製備方法
US20190140427A1 (en) * 2013-03-19 2019-05-09 Tresu A/S Unit and method for corona treatment

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1596577A (en) * 1978-02-08 1981-08-26 Milty Prod Ltd Enhanced sound reproduction from gramophone records
DE3272402D1 (en) * 1981-01-05 1986-09-11 Polaroid Corp Method and apparatus of producing a relatively high charge on charge-retaining materials
JP2817056B2 (ja) * 1989-06-05 1998-10-27 富士写真フイルム株式会社 塗布方法

Cited By (38)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3892614A (en) * 1973-03-08 1975-07-01 Simco Co Inc Electrostatic laminating apparatus and method
US3916063A (en) * 1973-10-11 1975-10-28 Thilmany Pulp & Paper Company Method for manufacturing a printable, glueable polyolefin web material
US3865480A (en) * 1973-12-20 1975-02-11 Xerox Corp Electrostatic control of fan fold paper stacking
US4055685A (en) * 1975-04-30 1977-10-25 Agfa-Gevaert Aktiengesellschaft Process for the improvement of the adhesion of photographic layers to a film web by means of a corona treatment
US4271451A (en) * 1976-07-20 1981-06-02 Hercules Incorporated Method and apparatus for controlling static charges
US4233562A (en) * 1978-11-08 1980-11-11 Imperial Chemical Industries Limited Apparatus and method for monitoring web conductivity
US4216254A (en) * 1979-05-05 1980-08-05 Union Carbide Corporation Method of selectively treating a plastic film surface to prevent blocking
US4486808A (en) * 1982-12-03 1984-12-04 Polaroid Corporation Apparatus for controlling random charges on a moving web
EP0136606A2 (de) * 1983-10-03 1985-04-10 Polaroid Corporation Verfahren und Geräte zur gleichförmigen Aufladung einer bewegten Bahn
US4517143A (en) * 1983-10-03 1985-05-14 Polaroid Corporation Method and apparatus for uniformly charging a moving web
EP0136606A3 (de) * 1983-10-03 1986-09-10 Polaroid Corporation Verfahren und Geräte zur gleichförmigen Aufladung einer bewegten Bahn
US4743258A (en) * 1984-04-27 1988-05-10 Japan Medical Supply Co., Ltd. Polymer materials for vascular prostheses
US4780680A (en) * 1984-11-03 1988-10-25 Hoechst Aktiengesellschaft Process for the continuous, contact-free measurement of layer thicknesses and apparatus for performing the process
US4810432A (en) * 1987-12-28 1989-03-07 Polaroid Corporation Method and apparatus for establishing a uniform charge on a substrate
US5805407A (en) * 1995-09-07 1998-09-08 Fuji Photo Film Co., Ltd. Charge eliminating apparatus for a moving web
US6312767B2 (en) * 1997-11-05 2001-11-06 L'air Liquide, Societe Anonyme Pour L'exploitation Des Procedes Georges Claude Process and device for the surface treatment of a substrate by an electrical discharge between two electrodes in a gas mixture
US6171658B1 (en) * 1998-02-06 2001-01-09 Eastman Kodak Company Coating method using electrostatic assist
US6517909B1 (en) * 1998-12-16 2003-02-11 Eastman Kodak Company Method for using a patterned backing roller for curtain coating a liquid composition to a web
US6475572B2 (en) 2000-04-06 2002-11-05 3M Innovative Properties Company Electrostatically assisted coating method with focused web-borne charges
US6666918B2 (en) 2000-04-06 2003-12-23 3M Innovative Properties Company Electrostatically assisted coating apparatus with focused web charge field
US6716286B2 (en) 2000-04-06 2004-04-06 3M Innovative Properties Company Electrostatically assisted coating method and apparatus with focused electrode field
US6368675B1 (en) 2000-04-06 2002-04-09 3M Innovative Properties Company Electrostatically assisted coating method and apparatus with focused electrode field
US20040072664A1 (en) * 2001-02-14 2004-04-15 Mario Spatafora Method and a device for checking wrapping material in a packaging machine
US7406809B2 (en) * 2001-02-14 2008-08-05 G.D S.P.A. Method and a device for checking wrapping material in a packaging machine
US6745001B2 (en) 2002-05-06 2004-06-01 Nexpress Solutions Llc Web conditioning charging station
US20040085705A1 (en) * 2002-10-30 2004-05-06 Zaretsky Mark C. Electrostatic charge neutralization using grooved roller surface patterns
US7095600B2 (en) 2002-10-30 2006-08-22 Eastman Kodak Company Electrostatic charge neutralization using grooved roller surface patterns
US20090009922A1 (en) * 2005-01-28 2009-01-08 Toray Industries, Inc. Electric-insulating sheet neutralizing device, neturalizing method and production method
WO2009002665A1 (en) * 2007-06-22 2008-12-31 3M Innovative Properties Company Apparatus and methods for modification of electrostatic charge on a moving web
US20100182728A1 (en) * 2007-06-22 2010-07-22 Jendrejack Richard M Apparatus and methods for modification of electrostatic charge on a moving web
US8570703B2 (en) 2007-06-22 2013-10-29 3M Innovative Properties Company Apparatus and methods for modification of electrostatic charge on a moving web
CN101690417B (zh) * 2007-06-22 2014-07-09 3M创新有限公司 用于调整移动幅材上的静电荷的装置和方法
WO2009085751A1 (en) * 2007-12-21 2009-07-09 3M Innovative Properties Company Apparatus and methods for altering charge on a dielectric material
US8605406B2 (en) 2007-12-21 2013-12-10 3M Innovative Properties Company Apparatus and methods for altering charge on a dielectric material
TWI406811B (zh) * 2010-02-03 2013-09-01 Beijing Funate Innovation Tech 奈米碳管膜之製備方法
US8320817B2 (en) 2010-08-18 2012-11-27 Eastman Kodak Company Charge removal from a sheet
WO2012054316A1 (en) 2010-10-21 2012-04-26 Eastman Kodak Company Concurrently removing sheet charge and curl
US20190140427A1 (en) * 2013-03-19 2019-05-09 Tresu A/S Unit and method for corona treatment

Also Published As

Publication number Publication date
BE786484A (fr) 1972-11-16
DE2237282B2 (de) 1974-03-21
DE2237282A1 (de) 1973-02-15
CA978499A (en) 1975-11-25
AU4509272A (en) 1974-01-31
BR7205054D0 (pt) 1973-05-15
JPS4825071A (de) 1973-04-02
FR2147997A1 (de) 1973-03-11
FR2147997B1 (de) 1975-03-07

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