Patents by Inventor Michael A. Mitchell

Michael A. Mitchell 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).

  • Patent number: 6159591
    Abstract: Multicomponent superabsorbent gel particles are disclosed. The multicomponent particles comprise at least one acidic water-absorbing resin and at least one basic water-absorbing resin. Each particle contains at least one microdomain of the acidic resin in contact with, or in close proximity to, at least one microdomain of the basic resin.
    Type: Grant
    Filed: July 15, 1998
    Date of Patent: December 12, 2000
    Assignee: AMCOL International Corporation
    Inventors: Thomas W. Beihoffer, Michael A. Mitchell
  • Patent number: 6121409
    Abstract: Poly(vinylamine)-based superabsorbent gels are disclosed. The superabsorbent gels either comprise a mixture of a poly(vinylamine) polymer and an acidic water-absorbing polymer, like polyacrylic acid, or comprise a salt of a poly(vinylamine) polymer. An improved method of preparing poly(vinylamine) also is disclosed.
    Type: Grant
    Filed: April 13, 1999
    Date of Patent: September 19, 2000
    Assignee: AMCOL International Corporation
    Inventors: Michael A. Mitchell, Thomas W. Beihoffer, Leticia L. Lobo, Jerald W. Darlington, Jr.
  • Patent number: 6087448
    Abstract: Poly(vinylguanidine)-based superabsorbent gels are disclosed. The superabsorbent gels either comprise a mixture of a poly(vinylguanidine) polymer and an acidic water-absorbing polymer, like polyacrylic acid, or comprise a salt of a poly(vinylguanidine) polymer.
    Type: Grant
    Filed: November 19, 1997
    Date of Patent: July 11, 2000
    Assignee: AMCOL International Corporation
    Inventors: Michael A. Mitchell, Thomas W. Beihoffer
  • Patent number: 6072101
    Abstract: Multicomponent superabsorbent gel particles are disclosed. The multicomponent particles comprise at least one acidic water-absorbing resin and at least one basic water-absorbing resin. Each particle contains microdomains of the acidic resin and/or the basic resin homogeneously dispersed throughout the particle.
    Type: Grant
    Filed: November 19, 1997
    Date of Patent: June 6, 2000
    Assignee: Amcol International Corporation
    Inventors: Thomas W. Beihoffer, Michael A. Mitchell
  • Patent number: 5998493
    Abstract: A superabsorbent foam material is made by a water-in-oil high internal phase emulsion polymerization comprising the steps of (a) dissolving an organic solvent-soluble surfactant in a water-insoluble monomer to form an organic phase; (b) blending the-organic phase with an aqueous phase using high shear mixing to form an emulsion, said aqueous phase comprising a water-soluble polymer, a cross-linking agent, and water; (c) polymerizing the water-insoluble monomer in the organic phase; (d) cross-linking the water-soluble polymer in the aqueous phase; and (e) final curing and drying the resulting foam.
    Type: Grant
    Filed: February 12, 1999
    Date of Patent: December 7, 1999
    Assignee: AMCOL International Corporation
    Inventors: Michael A. Mitchell, Anthony S. Tomlin
  • Patent number: 5981689
    Abstract: Poly(vinylamine)-based superabsorbent gels are disclosed. The superabsorbent gels either comprise a mixture of a poly(vinylamine) polymer and an acidic water-absorbing polymer, like polyacrylic acid, or comprise a salt of a poly(vinylamine) polymer. An improved method of preparing poly(vinylamine) also is disclosed.
    Type: Grant
    Filed: November 19, 1997
    Date of Patent: November 9, 1999
    Assignee: Amcol International Corporation
    Inventors: Michael A. Mitchell, Thomas W. Beihoffer, Leticia L. Trzupek, Jerald W. Darlington, Jr.
  • Patent number: 5962578
    Abstract: Poly(dialkylaminoalkyl (meth)acrylamide)-based superabsorbent gels are disclosed. The superabsorbent gels either comprise a mixture of a poly(dialkylaminoalkyl (meth) acrylamide) polymer and an acidic water-absorbing polymer, like polyacrylic acid, or comprise a salt of a poly(dialkylaminoalkyl (meth)acrylamide) polymer. An improved method of preparing an N-(dialkylaminoalkyl) (meth)acrylamide monomer also is disclosed.
    Type: Grant
    Filed: November 19, 1997
    Date of Patent: October 5, 1999
    Assignee: AMCOL International Corporation
    Inventors: Thomas W. Beihoffer, Michael A. Mitchell, Leticia L. Trzupek
  • Patent number: 5900437
    Abstract: A superabsorbent foam material is made by a water-in-oil high internal phase emulsion polymerization comprising the steps of (a) dissolving an organic solvent-soluble surfactant in a water-insoluble monomer to form an organic phase; (b) blending the-organic phase with an aqueous phase using high shear mixing to form an emulsion, said aqueous phase comprising a water-soluble polymer, a cross-linking agent, and water; (c) polymerizing the water-insoluble monomer in the organic phase; (d) cross-linking the water-soluble polymer in the aqueous phase; and (e) final curing and drying the resulting foam.
    Type: Grant
    Filed: June 2, 1997
    Date of Patent: May 4, 1999
    Assignee: AMCOL International Corporation
    Inventors: Michael A. Mitchell, Anthony S. Tomlin
  • Patent number: 5710187
    Abstract: Condensation polymerization followed by a supercritical extraction step can be used to obtain highly cross-linked nanoporous polymers with high surface area, controlled pore sizes and rigid structural integrity. The invention polymers are useful for applications requiring separation membranes.
    Type: Grant
    Filed: November 29, 1995
    Date of Patent: January 20, 1998
    Assignee: The Regents of the University of California
    Inventors: Warren P. Steckle, Jr., Paul G. Apen, Michael A. Mitchell
  • Patent number: 5629353
    Abstract: Condensation polymerization followed by a supercritical extraction step can be used to obtain highly cross-linked nanoporous polymers with high surface area, controlled pore sizes and rigid structural integrity. The invention polymers are useful for applications requiring separation membranes.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: May 13, 1997
    Assignee: The Regents of the University of California
    Inventors: Warren P. Steckle, Jr., Paul G. Apen, Michael A. Mitchell
  • Patent number: 5453701
    Abstract: Bare die test device for making temporary electrical connections between bonding pads on the die and external test connectors includes a die chuck, a fanout substrate, and a substrate chuck. The fanout substrate has conductive bumps spaced for registration with die bonding pads. A die chuck receives the die and a substrate chuck holds the fanout substrate. In a fixed alignment embodiment, an alignment arrangement between the die chuck and the substrate chuck provides registration. In an alternative embodiment, the fanout substrate has a backside etched cavity exposing a transparent compliant material. A lower frame provides for lateral and angular positioning of the die chuck relative to the substrate chuck to bring the conductive bumps into alignment with the bonding pads, while visually observing the alignment through the transparent material.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: September 26, 1995
    Assignee: Honeywell Inc.
    Inventors: Ronald J. Jensen, Michael A. Mitchell
  • Patent number: 5382665
    Abstract: A process of preparing an oxazoline or oxazine compound of the formula ##STR1## wherein X is an atom selected from the group of oxygen and sulfur, R is selected from the group consisting of C.sub.1-10 alkyl, C.sub.1-10 fluoroalkyl, aryl and substituted-aryl, and n is 2 or 3 comprising ring-closing a compound of the formula ##STR2## wherein X is an atom selected from the group of oxygen and sulfur, R is selected from the group consisting of C.sub.1-10 alkyl, C.sub.1-10 fluoroalkyl, aryl, and substituted aryl, n is 2 or 3, and Y is a bromine or chlorine atom in the presence of a basic reagent consisting essentially of a fluoride salt supported on an inorganic solid substrate is disclosed together with the compounds, 5-bromomethyl-2-phenyl-1,3-oxazoline, 5-methylene-2-phenyl-1,3-oxazine and 4,4-dimethyl-2-vinyl-1,3-oxazoline.
    Type: Grant
    Filed: March 17, 1993
    Date of Patent: January 17, 1995
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Brian C. Benicewicz, Michael A. Mitchell