Patents by Inventor Ravi K. Sura

Ravi K. Sura has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20180147766
    Abstract: Method for using sheets comprising co-extruded multi-component arrays that exhibit chromatically variable appearance dependent upon observation angle.
    Type: Application
    Filed: May 27, 2016
    Publication date: May 31, 2018
    Inventors: Ravi K. Sura, Thomas P. Hanschen, Ronald W. Ausen, Bridget K. Warmka
  • Patent number: 9625123
    Abstract: Lens assemblies for use in remote phosphor lighting systems, and methods of making and using them, are described. The lens assemblies typically include a lens member, a dichroic reflector attached to an outer surface of the lens member, and a phosphor layer attached to an inner surface of the lens member. The dichroic reflector reflects LED light originating from a given source point in a reference plane proximate the inner surface to a given image point in the reference plane. The phosphor layer may be patterned to cover one or more first portions of the inner surface and to expose one or more second portions, and/or the phosphor layer may be removably bonded to the inner surface. The lens assemblies can be readily combined with one or more short wavelength (e.g. blue) LEDs and other components to provide a remote phosphor lighting system.
    Type: Grant
    Filed: June 14, 2012
    Date of Patent: April 18, 2017
    Assignee: 3M INNOVATIVE PROPERTIES COMPANY
    Inventors: Andrew J. Ouderkirk, Ravi K. Sura, Nicholas T. Gabriel, Huang Chin Hung
  • Publication number: 20160347039
    Abstract: Sheets comprising co-extruded multi-component arrays that exhibit chromatically variable appearance dependent upon observation angle. Also, methods and apparatus for making such sheets and methods for using such sheets.
    Type: Application
    Filed: May 27, 2016
    Publication date: December 1, 2016
    Inventors: Ravi K. Sura, Thomas P. Hanschen, Ronald W. Ausen, Bridget K. Warmka
  • Publication number: 20150303129
    Abstract: A thermal interface material includes a conformable component and a thermally conductive filler dispersed in the conformable component. The material is provided in at least two segments laterally spaced from one another to define one or more gaps, each of the segments having a length, a width, and a height. The average aspect ratio of length to height and/or width to height of the at least two segments is between 1:10 and 10:1.
    Type: Application
    Filed: November 6, 2013
    Publication date: October 22, 2015
    Inventors: Andrew J. Ouderkirk, Ravi K. Sura, Hun Jeong
  • Publication number: 20140240928
    Abstract: A thermally conductive grease includes a carrier oil, at least one dispersant, and thermally conductive particles. The thermally conductive particles have a D50 (Vol. Average) particle size of no greater than about 11 microns and the thermally conductive particles in the thermally conductive grease contain less than 3% by volume of particles having a particle size of 0.7 microns or less, based on the total volume of thermally conductive particles in the thermally conductive grease.
    Type: Application
    Filed: September 28, 2012
    Publication date: August 28, 2014
    Inventors: Pei Tien, Chia Hui Lin, Chao-Yuan Wang, Ravi K. Sura
  • Publication number: 20140218938
    Abstract: Lens assemblies for use in remote phosphor lighting systems, and methods of making and using them, are described. The lens assemblies typically include a lens member, a dichroic reflector attached to an outer surface of the lens member, and a phosphor layer attached to an inner surface of the lens member. The dichroic reflector reflects LED light originating from a given source point in a reference plane proximate the inner surface to a given image point in the reference plane. The phosphor layer may be patterned to cover one or more first portions of the inner surface and to expose one or more second portions, and/or the phosphor layer may be removably bonded to the inner surface. The lens assemblies can be readily combined with one or more short wavelength (e.g. blue) LEDs and other components to provide a remote phosphor lighting system.
    Type: Application
    Filed: June 14, 2012
    Publication date: August 7, 2014
    Applicant: 3M INNOVATIVE PROPERTIES COMPANY
    Inventors: Andrew J. Ouderkirk, Ravi K. Sura, Nicholas T. Gabriel, Huang Chin Hung
  • Patent number: 8308991
    Abstract: Provided are adhesive compositions comprising a mixture of a maleimide terminated polyimide resin, a thermoplastic resin compatible with the maleimide terminated polyimide resin, a liquid rubber, and a thermally activated free radical curing agent. Various embodiments add one or more of a silane coupling agent, an ethylenically unsaturated compound with acid functionality, electrically conductive particles, and electrically conductive scrim. Methods of using the compositions also are provided.
    Type: Grant
    Filed: September 9, 2008
    Date of Patent: November 13, 2012
    Assignee: 3M Innovative Properties Company
    Inventors: Eric G. Larson, Robert L. D. Zenner, Cameron T. Murray, Ravi K. Sura
  • Patent number: 7883769
    Abstract: The invention is directed in part to an article that includes a polymer foam having a surface with surface microstructures, the surface microstructures have at least one extent or dimension of about 10 microns or more, preferably 50 microns or more. A maximum extent (unless it is a continuous rib-like structure) the microstructure is about 300 microns or less, preferably 200 microns or less, and generally a maximum height of 1000 microns or less, preferably 750 microns or less and a minimum height of 200 microns or more, preferably 300 microns or more. The foamed article may be provided in a variety of shapes, including a rod, a cylinder, a sheet, etc. In a preferred embodiment where the foam is provided in the form of a sheet, the foam has a pair of major surfaces, one or both of which can be provided with surface microstructures.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: February 8, 2011
    Assignee: 3M Innovative Properties Company
    Inventors: Jayshree Seth, Christopher K. Haas, Ravi K. Sura, Katherine A. S. Graham, Janet A. Venne
  • Publication number: 20110008570
    Abstract: The invention is directed in part to an article that includes a polymer foam having a surface with surface microstructures, the surface microstructures have at least one extent or dimension of about 10 microns or more, preferably 50 microns or more. A maximum extent (unless it is a continuous rib-like structure) the microstructure is about 300 microns or less, preferably 200 microns or less, and generally a maximum height of 1000 microns or less, preferably 750 microns or less and a minimum height of 200 microns or more, preferably 300 microns or more. The foamed article may be provided in a variety of shapes, including a rod, a cylinder, a sheet, etc. In a preferred embodiment where the foam is provided in the form of a sheet, the foam has a pair of major surfaces, one or both of which can be provided with surface microstructures.
    Type: Application
    Filed: September 23, 2010
    Publication date: January 13, 2011
    Inventors: Jayshree Seth, Christopher K. Haas, Ravi K. Sura, Katherine A.S. Graham, Janet A. Venne
  • Publication number: 20100197533
    Abstract: The invention relates to thermally conductive greases that may contain carrier oil(s), dispersant(s), and thermally conductive particles, wherein the thermally conductive particles are a mixture of at least three distributions of thermally conductive particles, each of the at least three distributions of thermally conductive particles having an average (D50) particle size which differs from the other average particle sizes by at least a factor of five. The thermally conductive greases of the invention exhibit desirable rheological behavior during installation/application and during use of devices involving these materials.
    Type: Application
    Filed: August 15, 2007
    Publication date: August 5, 2010
    Applicant: 3M Innovative Properties Company
    Inventors: Philip E. Kendall, Ravi K. Sura
  • Publication number: 20090087591
    Abstract: Provided are adhesive compositions comprising a mixture of a maleimide terminated polyimide resin, a thermoplastic resin compatible with the maleimide terminated polyimide resin, a liquid rubber, and a thermally activated free radical curing agent. Various embodiments add one or more of a silane coupling agent, an ethylenically unsaturated compound with acid functionality, electrically conductive particles, and electrically conductive scrim. Methods of using the compositions also are provided.
    Type: Application
    Filed: September 9, 2008
    Publication date: April 2, 2009
    Inventors: Eric G. Larson, Robert L.D. Zenner, Cameron T. Murray, Ravi K. Sura
  • Patent number: 7094463
    Abstract: The present invention is directed to a process for producing a polypropylene foam by mixing a high melt strength polypropylene and a blowing agent to form a melt mixture, reducing the temperature of the melt mixture at the exit of the apparatus to an exit temperature that is no more than 30° C. above the melt temperature of the neat polypropylene while maintaining the melt mixture at a pressure sufficient to prevent foaming; passing the mixture through said exit shaping orifice and exposing the mixture to atmospheric pressure, whereby the blowing agent expands causing cell formation resulting in foam formation, and orienting said foam. The foam is useful as tape backings, thermal and acoustical insulation and as a diffuse reflector for use in optical applications such as computer displays.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: August 22, 2006
    Assignee: 3M Innovative Properties Company
    Inventors: Christopher K. Haas, Mark D. Gehlsen, Sara B. Mortenson, Joan M. Strobel, Ravi K. Sura, David L. Vall
  • Patent number: 6977113
    Abstract: Microfiber articles and methods and intermediates for their production, the microfiber articles being preferably produced from co-extruded multi-layer films, and the articles having a multi-layer construction that allows selection of the different layers to have different properties.
    Type: Grant
    Filed: October 9, 2001
    Date of Patent: December 20, 2005
    Assignee: 3M Innovative Properties Company
    Inventors: Robert S. Kody, Mario A. Perez, John W. Longabach, Kimberley D. Klepzig, John M. Sebastian, Terry R. Hobbs, Matthew J. Michel, Timothy J. Lindquist, Ravi K. Sura
  • Patent number: 6890963
    Abstract: This invention relates to foams made by polymerizing high internal phase emulsions (HIPE) containing polyelectrolytes. The emulsions comprise a continuous oil phase and a co- or discontinuous aqueous phase. The resulting foams are useful as a separations medium.
    Type: Grant
    Filed: March 8, 2004
    Date of Patent: May 10, 2005
    Assignee: 3M Innovative Properties Company
    Inventors: Susannah C. Clear, Ranjani V. Parthasarathy, Ravi K. Sura, Philip P. Soo
  • Publication number: 20040258902
    Abstract: The invention is directed in part to an article that includes a polymer foam having a surface with surface microstructures, the surface microstructures have at least one extent or dimension of about 10 microns or more, preferably 50 microns or more. A maximum extent (unless it is a continuous rib-like structure) the microstructure is about 300 microns or less, preferably 200 microns or less, and generally a maximum height of 1000 microns or less, preferably 750 microns or less and a minimum height of 200 microns or more, preferably 300 microns or more. The foamed article may be provided in a variety of shapes, including a rod, a cylinder, a sheet, etc. In a preferred embodiment where the foam is provided in the form of a sheet, the foam has a pair of major surfaces, one or both of which can be provided with surface microstructures.
    Type: Application
    Filed: June 18, 2003
    Publication date: December 23, 2004
    Applicant: 3M Innovative Properties Company
    Inventors: Jayshree Seth, Christopher K. Haas, Ravi K. Sura, Katherine A.S. Graham, Janet A. Venne
  • Publication number: 20040204510
    Abstract: This invention relates to foams made by polymerizing high internal phase emulsions (HIPE) containing polyelectrolytes. The emulsions comprise a continuous oil phase and a co- or discontinuous aqueous phase. The resulting foams are useful as a separations medium.
    Type: Application
    Filed: March 8, 2004
    Publication date: October 14, 2004
    Applicant: 3M Innovative Properties Company
    Inventors: Susannah C. Clear, Ranjani V. Parthasarathy, Ravi K. Sura, Philip P. Soo
  • Patent number: 6750261
    Abstract: This invention relates to foams made by polymerizing high internal phase emulsions (HIPE) containing polyelectrolytes. The emulsions comprise a continuous oil phase and a co- or discontinuous aqueous phase. The resulting foams are useful as a separations medium.
    Type: Grant
    Filed: April 8, 2003
    Date of Patent: June 15, 2004
    Assignee: 3M Innovative Properties Company
    Inventors: Susannah C. Clear, Ranjani V. Parthasarathy, Ravi K. Sura, Philip P. Soo
  • Patent number: 6692823
    Abstract: Described are hydrophilic fibrillated articles that include melt-processable polymer and hydrophilic component such as hydrophilic surfactant or hydrophilic polymer, as well as methods of preparing such articles.
    Type: Grant
    Filed: December 19, 2001
    Date of Patent: February 17, 2004
    Assignee: 3M Innovative Properties Company
    Inventors: Robert S. Kody, Mario A. Perez, Thomas P. Klun, Paul D. Graham, Christopher K. Haas, Ravi K. Sura, Diane R. Wolk, Julie S. Prudich, Larry R. Krepski, Terry R. Hobbs, John M. Sebastian, Paul DeRoussel
  • Publication number: 20030138612
    Abstract: Described are hydrophilic fibrillated articles comprising melt-processable polymer and hydrophilic component such as hydrophilic surfactant or hydrophilic polymer, as well as methods of preparing such articles.
    Type: Application
    Filed: December 19, 2001
    Publication date: July 24, 2003
    Applicant: 3M Innovative Properties Company
    Inventors: Robert S. Kody, Mario A. Perez, Thomas P. Klun, Paul D. Graham, Christopher K. Haas, Ravi K. Sura, Diane R. Wolk, Julie S. Prudich, Larry R. Krepski, Terry R. Hobbs, John M. Sebastian, Paul DeRoussel
  • Publication number: 20030105176
    Abstract: The present invention is directed to a process for producing a polypropylene foam by mixing a high melt strength polypropylene and a blowing agent to form a melt mixture, reducing the temperature of the melt mixture at the exit of the apparatus to an exit temperature that is no more than 30° C. above the melt temperature of the neat polypropylene while maintaining the melt mixture at a pressure sufficient to prevent foaming; passing the mixture through said exit shaping orifice and exposing the mixture to atmospheric pressure, whereby the blowing agent expands causing cell formation resulting in foam formation, and orienting said foam. The foam is useful as tape backings, thermal and acoustical insulation and as a diffuse reflector for use in optical applications such as computer displays.
    Type: Application
    Filed: December 30, 2002
    Publication date: June 5, 2003
    Inventors: Christopher K. Haas, Mark D. Gehlsen, Sara B. Mortenson, Joan M. Strobel, Ravi K. Sura, David L. Vall