Plasma (e.g., Corona, Glow Discharge, Etc.) Patents (Class 264/423)
  • Patent number: 10240269
    Abstract: Electret webs include a thermoplastic resin and a charge-enhancing additive. The charge-enhancing additive is a fused aromatic thiourea, a fused aromatic urea compound, or a combination thereof. The change-enhancing additive may also include a hindered amine light stabilizer compound. The electret webs may be a non-woven fibrous web or a film. The electret webs are suitable for use as filter media.
    Type: Grant
    Filed: June 9, 2015
    Date of Patent: March 26, 2019
    Assignee: 3M Innovative Properties Company
    Inventors: Nathan E. Schultz, Fuming B. Li, John M. Sebastian
  • Patent number: 9034199
    Abstract: A machined ceramic article having an initial surface defect density and an initial surface roughness is provided. The machined ceramic article is heated to a temperature range between about 1000° C. and about 1800° C. at a ramping rate of about 0.1° C. per minute to about 20° C. per minute. The machined ceramic article is heat-treated in air atmosphere. The machined ceramic article is heat treated at one or more temperatures within the temperature range for a duration of up to about 24 hours. The machined ceramic article is then cooled at the ramping rate, wherein after the heat treatment the machined ceramic article has a reduced surface defect density and a reduced surface roughness.
    Type: Grant
    Filed: October 24, 2012
    Date of Patent: May 19, 2015
    Assignee: Applied Materials, Inc.
    Inventors: Ren-Guan Duan, Thorsten Lill, Jennifer Y. Sun, Benjamin Schwarz
  • Patent number: 8790449
    Abstract: Electret webs are presented which include a blend of a thermoplastic resin and a charge-enhancing additive. The charge-enhancing additives include a heterocyclic imide material which is free of fluorinated groups. The webs prepared from the blends may be in the form of films or non-woven fibrous webs. Non-woven microfiber webs are useful as filtration media.
    Type: Grant
    Filed: March 23, 2010
    Date of Patent: July 29, 2014
    Assignee: 3M Innovative Properties Company
    Inventors: Fuming B. Li, John M. Sebastian, Marvin E. Jones, Daniel A. Japuntich
  • Publication number: 20140144323
    Abstract: The present invention discloses a silica-like membrane for separating gas, which is modified from poly(dimethylsiloxane) (PDMS) membrane by an atmospheric pressure high temperature plasma torch (APHTPT). Furthermore, the present invention of the separating gas silica-like membrane with an inorganic/organic interface structure which has both the gas flux of the organic membrane and also the gas selectivity of the inorganic membrane.
    Type: Application
    Filed: November 30, 2012
    Publication date: May 29, 2014
    Applicant: CHUNG YUAN CHRISTIAN UNIVERSITY
    Inventors: Jung-Tsai Chen, Ywu-Jang Fu, Kuo-Lun Tung, Shu-Hsien Huang, Wei-Song Hung, Shingjiang Jessie Lue, Chien-Chieh Hu, Kueir-Rarn Lee, Juin-Yih Lai
  • Patent number: 8709351
    Abstract: A continuous feed discharge surface treater for treating web materials has a discharge chamber where ionization of a process gas occurs defined and contained by one or more rollers. Enhanced chemical coronas and plasmas are achieved by limiting depletion of the gas chemistry from the discharge chamber and dilution or contamination from mixing with drawn in ambient air. Atmospheric coronas can also be achieved in which minimal or no ozone is exhausted from the treater. Various roller and electrode assemblies, including both fixed and rolling electrodes, can be employed.
    Type: Grant
    Filed: October 22, 2008
    Date of Patent: April 29, 2014
    Assignee: Enercon Industris Corporation
    Inventors: Richard R. Hammen, Joseph Roethle, Gregory W. Schuelke
  • Patent number: 8668093
    Abstract: Versions of the invention include compositions and methods for making them that include a polymeric porous membrane with one or more atmospheric pressure microwave plasma modified surfaces. The modified porous membrane is stable, non-dewetting, and retains its mechanical strength.
    Type: Grant
    Filed: May 11, 2011
    Date of Patent: March 11, 2014
    Assignee: Entegris, Inc.
    Inventors: Jijun Ge, Alketa Gjoka, Jieh-Hwa Shyu
  • Publication number: 20140009039
    Abstract: The present invention relates to a polymer layer structure with ferroelectret properties, comprising a continuous first polymer layer (1) and a continuous second polymer layer (2), the first and second polymer layers (1, 2) being connected to one another to form voids (4) by connecting portions (3) arranged between the continuous polymer layers (1, 2). According to the invention, the polymer layer structure is in the form of an integral extruded structural element.
    Type: Application
    Filed: October 28, 2011
    Publication date: January 9, 2014
    Applicant: BAYER INTELLECTUAL PROPERTY GMBH
    Inventors: Werner Jenninger, Deliani Lovera-Prieto
  • Patent number: 8613795
    Abstract: Electret webs are presented which include a blend of a thermoplastic resin and a charge-enhancing additive. The charge-enhancing additives include N-substituted amino carbocyclic aromatic materials. The webs prepared from the blends may be in the form of films or non-woven fibrous webs. Non-woven microfiber webs are useful as filtration media.
    Type: Grant
    Filed: May 4, 2009
    Date of Patent: December 24, 2013
    Assignee: 3M Innovative Properties Company
    Inventors: Fuming B. Li, Feng Bai, John M. Sebastian, Marvin E. Jones
  • Patent number: 8609014
    Abstract: According to one embodiment, a template manufacturing method is a method for manufacturing a template for use in an imprint processing in which a pattern having irregularities are formed on a principal surface, and the pattern is brought into contact with a resist member formed on a substrate to be processed, to transfer the pattern to the resist member, the method including implanting charged particles at least into the bottoms of concave portions of the template.
    Type: Grant
    Filed: June 1, 2011
    Date of Patent: December 17, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsukasa Azuma, Tatsuhiko Higashiki, Kyoichi Suguro
  • Patent number: 8378694
    Abstract: Applicant discloses a sensing element for sensing an organic chemical analyte, comprising a first electrode and a second electrode, and a microporous, hydrophobic, analyte-responsive dielectric material disposed at least in proximity to the first and second electrodes. The analyte-responsive dielectric material may be an amorphous random covalent network comprising a mean pore size of less than about 10 nm and a porosity of at least about 20%. An electrical property of the sensing element, such as capacitance, can be monitored in order to sense an organic chemical analyte.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: February 19, 2013
    Assignee: 3M Innovative Properties Company
    Inventors: Moses M. David, Stefan H. Gryska, Nelson B. O'Bryan, Neal A. Rakow, Michael S. Wendland
  • Patent number: 8377172
    Abstract: The present invention relates to new fibers, new processes of using said fibers, and new sheath dope compositions for multi-layer spinning processes. The fibers comprise a porous core and a sheath surrounding said porous core. The fibers may be useful in, for example, processes for removing low level contaminants like sulfur compounds from a gas stream like natural gas.
    Type: Grant
    Filed: October 13, 2009
    Date of Patent: February 19, 2013
    Assignee: Georgia Tech Research Corporation
    Inventors: William John Koros, Dhaval A. Bhandari
  • Publication number: 20110210063
    Abstract: Versions of the invention include compositions and methods for making them that include a polymeric porous membrane with one or more atmospheric pressure microwave plasma modified surfaces. The modified porous membrane is stable, non-dewetting, and retains its mechanical strength.
    Type: Application
    Filed: May 11, 2011
    Publication date: September 1, 2011
    Inventors: Jijun GE, Alketa Gjoka, Jieh-Hwa Shyu
  • Publication number: 20110057358
    Abstract: A method for producing a solid and/or porous film Includes preparing a suspension of solid particles in a solvent and spreading the suspension as a uniform layer of powder particles on a high melting point support. The solvent is eliminated so as to dry the uniform layer of powder particles into a dried porous uniform layer and surface melting/sintering of the dried uniform layer is carried out by direct contact with a concentrated heat source having a controlled gas composition so as to melt/sinter the layer into a solid/porous film.
    Type: Application
    Filed: August 28, 2007
    Publication date: March 10, 2011
    Inventors: Behnam Mostajeran Goortani, François Gitzhofer, Etienne Bouyer
  • Patent number: 7781028
    Abstract: Amorphous metal oxide thin film is produced by removing through oxygen plasma treatment the organic component from an organics/metal oxide composite thin film having thoroughly dispersed therein such organic component at molecular scale. This ensures production of amorphous metal oxide thin film with low density and excellent thickness precision.
    Type: Grant
    Filed: July 19, 2007
    Date of Patent: August 24, 2010
    Assignee: Riken
    Inventors: Toyoki Kunitake, Izumi Ichinose, Shigenori Fujikawa, Jianguo Huang
  • Publication number: 20100203400
    Abstract: A passive humidifier membrane includes polyolefin with a plurality of pores, wherein the average pore size of the plurality of pores is 0.05 ?m to 0.4 ?m as established by a PMI Capillary Flow Porometer. The humidifier membrane is virtually airtight while providing a high transfer rate of water. Transfer of heat is also high. The humidifier membrane is particularly suitable for heat exchange and water transfer between fluids and, it is particularly useful for applications inside or outside fuel cells such as PEMFC. The membrane is also particularly useful in the application as humidifier for air or oxygen.
    Type: Application
    Filed: October 9, 2007
    Publication date: August 12, 2010
    Applicant: Lydall Solutech B.V.
    Inventors: Gijsbertus Hendrikus Maria Calis, Adriaan Steenbakkers, Paul Osenar, Rich Formato, Paul Sabin, Seth Avis
  • Publication number: 20100156002
    Abstract: A microporous asymmetrical membrane formed of one or more layers wherein the “tight” side of the membrane has an “opened” face or otherwise highly-porous reticulated surface is described. The microporous asymmetrical membrane has high throughput and high flux, even when used for filtering viscous materials, such as serum or plasma. The membrane's surface can be formed by ablation or solvation, or in a two or more layered structure, through an appropriate selection of casting dopes.
    Type: Application
    Filed: February 22, 2010
    Publication date: June 24, 2010
    Applicant: Millipore Corporation
    Inventors: Willem Kools, Claire Marie Goulding, Daniel Calnan, Timothy Dolan
  • Patent number: 7691168
    Abstract: A charged multilayer filter includes a hydrocharged filtration layer containing a plurality of intertwined nanofibers that have a finite length of about 12 to about 300 mm, atop a porous roll-to-roll processable support layer.
    Type: Grant
    Filed: October 10, 2006
    Date of Patent: April 6, 2010
    Assignee: 3M Innovative Properties Company
    Inventors: Andrew R. Fox, Marvin E. Jones
  • Publication number: 20090315224
    Abstract: Shaped filtration articles are made from a monocomponent nonwoven web formed by flowing first and second fiber-forming materials of the same polymeric composition through first and second die cavities in respective fluid communication with first and second sets of orifices in a meltblowing die tip. The first fiber-forming material flows at a lesser flow rate or viscosity through the first die cavity and first set of orifices to form a set of smaller size filaments and the second fiber-forming material flows at a greater flow rate or viscosity through the second die cavity and second set of orifices to form a set of larger size filaments. The collected nonwoven web contains a meltblown bimodal mass fraction/fiber size mixture of intermingled continuous microfibers and larger size fibers of the same polymeric composition.
    Type: Application
    Filed: July 17, 2007
    Publication date: December 24, 2009
    Inventors: Seyed A. Angadjivand, Marvin E. Jones, James E. Springett, James E. Springett, John M. Brandner, Timothy J. Lindquist
  • Publication number: 20090123822
    Abstract: The present invention relates to a particular multi-layer microporous membrane having a good balance of important properties, including excellent electrochemical stability and low heat shrinkage, while maintaining high permeability and heat resistance, with good mechanical strength, compression resistance and electrolytic solution absorption. Of particular importance when used as a battery separator, the present multi-layer microporous membrane exhibits excellent heat shrinkage, melt down temperature and thermal mechanical properties, i.e. low maximum shrinkage in the molten state. The multi-layer microporous membrane of the present invention can be produced (or manufactured) by layering, such as for example by coextrusion, one or more microporous membrane second layers and one or more microporous membrane first layers, such as on one or both sides of a second layer.
    Type: Application
    Filed: November 9, 2007
    Publication date: May 14, 2009
    Inventors: Kotaro Takita, Shintaro Kikuchi
  • Publication number: 20090117454
    Abstract: The invention relates to a particular multi-layer microporous membrane having a good balance of important properties, including excellent electrochemical stability and low heat shrinkage, while maintaining high permeability and heat resistance, with good mechanical strength, compression resistance and electrolytic solution absorption. Of particular importance when used as a battery separator, the present multi-layer microporous membrane exhibits excellent heat shrinkage, melt down temperature and thermal mechanical properties, i.e. low maximum shrinkage in the molten state. The multi-layer microporous membrane of the present invention is manufactured by layering, such as for example by coextrusion, one or more microporous membrane first layers and one or more microporous membrane second layers, such as on one or both sides of a first layer. The invention further relates to battery separators comprising the multi-layer microporous membrane and batteries utilizing the battery separators.
    Type: Application
    Filed: November 2, 2007
    Publication date: May 7, 2009
    Inventors: Kotaro Takita, Shintaro Kikuchi
  • Publication number: 20090092893
    Abstract: The invention relates to a microporous membrane which comprises polyethylene, the microporous membrane having a differential pore volume curve with an area under the curve over the range of pore diameters of from about 100 nm to about 1,000 nm that is 25% or more of a total area under the curve over the range of pore diameters of from about 10 nm to about 1,000 nm.
    Type: Application
    Filed: October 5, 2007
    Publication date: April 9, 2009
    Inventors: Kotaro Takita, Shintaro Kikuchi
  • Publication number: 20090081543
    Abstract: A microporous polyolefin membrane having a structure in which its pore size distribution curve obtained by mercury intrusion porosimetry has at least two peaks, which is produced by extruding a melt-blend of a polyolefin composition comprising (a) high density polyethylene resin having a weight average molecular weight of from about 2.5×105 to about 5×105 and a molecular weight distribution of from about 5 to about 100, (b) polypropylene resin having a weight average molecular weight of from about 3×105 to about 1.
    Type: Application
    Filed: September 20, 2007
    Publication date: March 26, 2009
    Inventors: Kotaro Takita, Shintaro Kikuchi
  • Publication number: 20080169588
    Abstract: Two methods of extending the lifetime of yttrium oxide as a plasma chamber material are provided. One method comprises making a three-layer component of a plasma processing chamber by co-sintering a dual-layer green body where one layer comprises ceramic particles and a second layer comprises yttria particles. The two layers are in intimate contact during the sintering process. In a preferred embodiment, the three layer component comprises an outer layer of yttria, an intermediate layer of YAG, and a second outer layer of alumina. Optionally, the disks are pressed together during the sintering process. The resulting three-layer component is very low in porosity. Preferably, the porosity of any of the outer layer of yttria, the intermediate layer of YAG, and the second outer layer of alumina, is less than 3%.
    Type: Application
    Filed: January 11, 2007
    Publication date: July 17, 2008
    Applicant: Lam Research Corporation
    Inventors: Hong Shih, Duane Outka, Shenjian Liu, John Daugherty
  • Publication number: 20080160858
    Abstract: A microporous carbon material includes a porous carbon skeleton having an average pore size from 0.1 to 10 nanometers and being substantially free of pores greater than 1 micrometer. Methods of forming the microporous carbon material are also disclosed.
    Type: Application
    Filed: December 29, 2006
    Publication date: July 3, 2008
    Inventors: Dora M. Paolucci, Moses M. David, Neal A. Rakow, John E. Trend
  • Patent number: 6953544
    Abstract: A method of making a respirator, which method includes placing an electret in a respirator body that is adapted to fit over the nose and mouth of a wearer. The electret is disposed in the respirator body such that air passes through it before being inhaled by a respirator wearer. The electret includes a nonwoven web that has fluorinated polymeric microfibers and that has at least about 25% atomic fluorine as detected by ESCA and a CF3:CF2 ratio of at least about 0.45.
    Type: Grant
    Filed: May 7, 2004
    Date of Patent: October 11, 2005
    Assignee: 3M Innovative Properties Company
    Inventors: Marvin E. Jones, Christopher S. Lyons, David B. Redmond, Jeffrey L. Solomon, Seyed Abolhassan Angadjivand
  • Patent number: 6939389
    Abstract: The manufacture of pure, fine spherical powders has always been a problem for many materials, particularly for high-melting and highly reactive materials such as titanium, tantalum, vanadium and zirconium. The present invention provides a process and apparatus for producing such powders by rapidly heating course powders containing a gas or gases to near or above their melting point, whereby the contained gas erupts explosively to form many fine particles of the host material. The fine particles are typically, but not necessarily spheroidal, depending upon the process conditions at the time of eruption and immediately thereafter. Methods are described for producing, collecting, handling, storing and passivating said fine powders.
    Type: Grant
    Filed: August 8, 2003
    Date of Patent: September 6, 2005
    Inventors: Frank Mooney, Fay Nelson
  • Publication number: 20040207125
    Abstract: A method of making a respirator, which method includes placing an electret in a respirator body that is adapted to fit over the nose and mouth of a wearer. The electret is disposed in the respirator body such that air passes through it before being inhaled by a respirator wearer. The electret includes a nonwoven web that has fluorinated polymeric microfibers and that has at least about 25% atomic fluorine as detected by ESCA and a CF3:CF2 ratio of at least about 0.45.
    Type: Application
    Filed: May 7, 2004
    Publication date: October 21, 2004
    Applicant: 3M Innovative Properties Company
    Inventors: Marvin E. Jones, Christopher S. Lyons, David B. Redmond, Jeffrey L. Solomon, Seyed Abolhassan Angadjivand
  • Patent number: 6774155
    Abstract: The invention is directed to methods for fabricating devices from polymer precursors, along with devices so fabricated. The methods of the invention include the steps of plasma treating a polymer based resin, paste, preform billet, or extrudate, and employing the treated polymer in the fabricated device. According to one embodiment, the fabricated device can include implantable prosthetics such as heart valves, sutures, vascular access devices, vascular grafts, shunts, catheters, single layered membranes, double layered membranes, and the like. Devices fabricated according to one embodiment of the invention include regions having selected porosity, permeability and/or chemistry characteristics.
    Type: Grant
    Filed: July 16, 2002
    Date of Patent: August 10, 2004
    Assignee: Atrium Medical Corporation
    Inventors: Paul Martakos, Thomas M. Swanick, Theodore Karwoski
  • Patent number: 6669823
    Abstract: A process to prepare stoichiometric-nanostructured materials comprising generating a plasma, forming an “active volume” through introduction of an oxidizing gas into the plasma, before the plasma is expanded into a field-free zone, either (1) in a region in close proximity to a zone of charge carrier generation, or (2) in a region of current conduction between field generating elements, including the surface of the field generation elements, and transferring energy from the plasma to a precursor material to form in the “active volume” at least one stoichiometric-nanostructured material and a vapor that may be condensed to form a stoichiometric-nanostructured material. The surface chemistry of the resulting nanostructured materials is substantially enhanced to yield dispersion stable materials with large zeta-potentials.
    Type: Grant
    Filed: June 17, 2002
    Date of Patent: December 30, 2003
    Assignee: Nanophase Technologies Corporation
    Inventors: Harry W. Sarkas, Jonathan Piepenbrink
  • Patent number: 6660210
    Abstract: An electret is described that includes a plasma surface modified polymeric article having plasma surface fluorination produced by fluorinating the polymeric article.
    Type: Grant
    Filed: March 18, 2003
    Date of Patent: December 9, 2003
    Assignee: 3M Innovative Properties Company
    Inventors: Marvin E. Jones, Christopher S. Lyons, David B. Redmond, Jeffrey L. Solomon, Seyed Abolhassan Angadjivand
  • Patent number: 6579604
    Abstract: The present invention is directed, in general, to an improved material and method of planarizing a surface on a semiconductor wafer and, more specifically, to a method of altering the properties of polymers, preferably thermoplastic foam polymers, used in polishing applications. The chemical and mechanical properties thermoplastic foam substrates can be transformed by inorganic, inorganic-organic, and or organic—organic grafting techniques, such that the polymer foam is endowed with new set of properties that more desirable and suitable for polishing.
    Type: Grant
    Filed: November 27, 2001
    Date of Patent: June 17, 2003
    Assignee: PsiloQuest Inc.
    Inventors: Yaw S. Obeng, Edward M. Yokley
  • Patent number: 6573311
    Abstract: The invention is directed to methods for fabricating devices from polymer precursors, along with devices so fabricated. The methods of the invention include the steps of plasma treating a polymer based resin, paste, preform billet, or extrudate, and employing the treated polymer in the fabricated device. According to one embodiment, the fabricated device can include implantable prosthetics such as heart valves, sutures, vascular access devices, vascular grafts, shunts, catheters, single layered membranes, double layered membranes, and the like. Devices fabricated according to one embodiment of the invention include regions having selected porosity, permeability and/or chemistry characteristics.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: June 3, 2003
    Assignee: Atrium Medical Corporation
    Inventors: Paul Martakos, Thomas M. Swanick, Theodore Karwoski
  • Patent number: 6419871
    Abstract: The present invention is drawn to an improved electrostatic filter medium comprising a web of electret fibers which have been treated with fluorine-containing plasmas at a deposition amount of about 0.03 g/m2 to about 1.5 g/m2; electrostatically charged; rinsed; and dried. The present invention is further drawn to a method of producing non-woven webs which have been treated with a fluorine-containing plasma at a deposition amount of about 0.03 g/m2 to about 1.5 g/m2; electrostatically charged; rinsed; and dried.
    Type: Grant
    Filed: May 25, 2000
    Date of Patent: July 16, 2002
    Assignee: Transweb, LLC.
    Inventor: Kumar Ogale
  • Patent number: 6379605
    Abstract: Disclosed is a process for producing a three layers co-extrusion biaxially oriented polypropylene (hereinafter as BOPP) synthetic paper and transparent film for in-mold label. More particularly, the invention relates to a process for producing a three layers biaxially oriented PP synthetic paper by means of three layers co-extrusion wherein three different PP resin compositions are separately extruded by one primary and two secondary extruders first, and then are co-flowed by a same T-die to form a three layers coating sheet.
    Type: Grant
    Filed: October 22, 1999
    Date of Patent: April 30, 2002
    Assignee: Nan Ya Plastics Corporation
    Inventor: Allen Fong-Chin Lin
  • Patent number: 6368543
    Abstract: Disclosed is an improvement of a process for producing a three layers co-extrusion biaxially polypropylene(BOPP) synthetic paper of thickness 25˜250 &mgr;m which is menufactured by using three single screw extruders By means of an improvement of a process for producing a three layers co-extrusion biaxially polypropylene(hereinafter as BOPP) synthetic paper of thickness 25˜250 &mgr;m. More particularly, the invention relates to a process for producing a three layers BOPP synthetic paper by means of three layers co-extrusion wherein two different PP resin compositions are separately extruded by one primary single screw extruder with venting device and two secondary single screw extruders with venting device first, and then are co-flowed by a same T-die to form a three layers coating sheet, and through cooling, biaxial orientation, corona treatment and winding to form a three layers co-extrusion synthetic paper of thickness 25˜250 &mgr;m.
    Type: Grant
    Filed: September 13, 1999
    Date of Patent: April 9, 2002
    Assignee: Nan Ya Plastics Corporation
    Inventor: Allen Fong-Chin Lin
  • Patent number: 6364988
    Abstract: Disclosed is a process for producing a 3-layer co-extruded biaxially polypropylene (hereinafter as BOPP) synthetic paper of thickness 25-250 &mgr;m. More particularly, the invention relates to a process for producing a 3-layer biaxially-oriented PP synthetic paper by means of 3-layer co-extrusion wherein two different PP resin compositions are separately extruded by one primary and two secondary extruders first, and then are co-flowed by a same T-die to form a three layers coating sheet, and through cooling, biaxial orientation, corona treatment and winding to form a 3-layer co-extrusion synthetic paper of thickness 25-250 &mgr;m.
    Type: Grant
    Filed: September 13, 1999
    Date of Patent: April 2, 2002
    Assignee: Nan Ya Plastics Corporation
    Inventor: Allen Fong-Chin Lin
  • Patent number: 6136439
    Abstract: A monolayer printable polymeric film and method for making the film. The film is formed by mixing a structural material, such as polypropylene or polyethylene, with a printable material, such as vinyl-acetate or methacrylate, to form a unitary mixture prior to processing. The unitary mixture is extruded and heated so as to cause the printable material to bloom to the surface of the unitary mixture. Stretching of the mixture at temperatures greater than permissible for multi-layered films formed of separate structural and printable materials heat sets and relaxes or stress relieves the film that is formed. The result is a monolayer film that is stiffer and that lays much flatter than the prior multi-layered films that were prone to curling. The mixture is preferably heated to 270.degree. F. or greater during the stretching process.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: October 24, 2000
    Inventor: Theodore R. Coburn
  • Patent number: 6080471
    Abstract: The present invention provides a non-woven fabric for an alkali cell separator capable of preventing active materials from transfer, and having distinguished electrolyte solution absorbability and retainability in spite of a small areal weight and also provides a process for producing the same. The non-woven fabric is substantially free from perforations and has a center surface average roughness SRa of not more than 13 .mu.m at streaks of entanglement on at least one side of the non-woven fabric, a maximum pore diameter of not more than 50 .mu.m and a water absorbability under pressure of not less than 20 g/m.sup.2, and a standard deviation of pore diameter distribution of not more than 20 .mu.m, as determined by bubble point method.
    Type: Grant
    Filed: August 13, 1997
    Date of Patent: June 27, 2000
    Assignee: Mitsubishi Paper Mills Limited
    Inventors: Toshihiro Shigematsu, Yoshitami Ishikawa, Yasuyuki Oku
  • Patent number: 6068799
    Abstract: An electret article can be made by quenching a molten blend containing a polymer and a performance-enhancing additive. The resulting low crystallinity material can be annealed and charged to produce a material for making electret filters having superior oily mist loading performance properties.
    Type: Grant
    Filed: October 1, 1997
    Date of Patent: May 30, 2000
    Assignee: 3M Innovative Properties Company
    Inventors: Alan D. Rousseau, Marvin E. Jones, Betty Z. Mei
  • Patent number: 5830810
    Abstract: A plasma sterilizable fabric which is subjected to charging, for example electrostatic charging, is provided. Plasma sterilizable fabrics may include nonwovens and laminate nonwovens. The plasma sterilizable fabrics may also be treated with an antistatic material before or after subjecting the same to charging.
    Type: Grant
    Filed: February 20, 1997
    Date of Patent: November 3, 1998
    Assignee: Kimberly-Clark Worldwide, Inc.
    Inventor: Bernard Cohen
  • Patent number: 5688465
    Abstract: A method of preventing localized arcing to ground during treatment of a sheet material in a corona discharge field generated by a corona discharge apparatus having at least two electrodes, which method involves passing the sheet material to be treated through the corona discharge field, in which the sheet material to be treated is electrically isolated from the electrodes. When the corona discharge apparatus has a bare metal electrode and a dielectric-covered electrode, the sheet material to be treated is passed through the corona discharge field as a layer of a multilayered composite having at least three layers, in which at least one of the layers is a nonconductive sheet material situated between the sheet material to be treated and the bare metal electrode.
    Type: Grant
    Filed: May 13, 1996
    Date of Patent: November 18, 1997
    Assignee: Kimberly-Clark Worldwide, Inc.
    Inventor: David Lewis Myers
  • Patent number: 5643507
    Abstract: Filter media is provided. The filter media comprises a web of melt blown microfibers having one surface substantially flat and the other surface having periodic wrinkle-like undulations. A method of making the filter media is also provided. The filter media is useful in electret filters when charged.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: July 1, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Michael R. Berrigan, David A. Olson
  • Patent number: 5552011
    Abstract: The present invention is related to a process of manufacturing polyproylene (PP) synthetic paper and the product thereof, and particularly to a process of manufacturing synthetic paper by means of 3-layer co-extrusion wherein PP resin composite and resin composite are respectively extruded as an extrudate co-flow by one primary extruder and two secondary extruders and by same one T-type die to be a paper sheet with a paper surface layer, an intermediate layer and a paper surface layer, and through cooling/shaping, biaxial orientation, corona discharge treatment and laminating/rolling to be a synthetic paper depending on the required thickness.
    Type: Grant
    Filed: October 14, 1994
    Date of Patent: September 3, 1996
    Assignee: Nanya Plastics Corporation
    Inventor: Allen F. Lin
  • Patent number: 5496507
    Abstract: A method of charging a nonwoven web of thermoplastic microfibers to provide electret filter media is provided. The method includes impinging on a nonwoven web of thermoplastic nonconductive microfibers capable of having a high quantity of trapped charge jets of water or a stream of water droplets at a pressure sufficient to provide the web with filtration enhancing electret charge and drying said web.
    Type: Grant
    Filed: August 17, 1994
    Date of Patent: March 5, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Seyed A. Angadjivand, Marvin E. Jones, Daniel E. Meyer