Patents by Inventor W. James Hammar

W. James Hammar 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: 5753364
    Abstract: The present invention provides pressure sensitive adhesives, compositions from which the pressure sensitive adhesives are formed, and articles having therein these pressure sensitive adhesives. The pressure sensitive adhesives, which have a Tg of less than about 20.degree. C., include a poly(.beta.-hydroxyorganoate) or mixture thereof. Preferably, these poly(.beta.-hydroxyorganoate)s include monomeric units of the general formula: ##STR1## wherein a minor amount (preferably no greater than about 20 mole percent) of the monomeric units have an R group containing 1-3 carbon atoms; and a major amount (preferably at least about 80 mole percent) of the monomeric units have an R group containing 4-30 (preferably 4-20) carbon atoms.
    Type: Grant
    Filed: January 30, 1997
    Date of Patent: May 19, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Denise R. Rutherford, W. James Hammar, Gaddam N. Babu
  • Patent number: 5614576
    Abstract: The present invention provides pressure sensitive adhesives, compositions from which the pressure sensitive adhesives are formed, and articles having therein these pressure sensitive adhesives. The pressure sensitive adhesives, which have a Tg of less than about 20.degree. C., include a poly(.beta.-hydroxyorganoate) or mixture thereof. Preferably, these poly(.beta.-hydroxyorganoate)s include monomeric units of the general formula: ##STR1## wherein: a minor amount (preferably no greater than about 20 mole percent) of the monomeric units have an R group containing 1-3 carbon atoms; and a major amount (preferably at least about 80 mole percent) of the monomeric units have an R group containing 4-30 (preferably 4-20) carbon atoms.
    Type: Grant
    Filed: April 15, 1996
    Date of Patent: March 25, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Denise R. Rutherford, W. James Hammar, Gaddam N. Babu
  • Patent number: 5461133
    Abstract: An elastomeric orthodontic device such as a ligature, rotation wedge or force module is made of a composition selected from one or more classes of materials, such that the device has certain physical properties useful for orthodontic treatment and also is resistant to staining by common foods and beverages such as mustard, tea and coffee.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: October 24, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: W. James Hammar, Miriam D. Nave
  • Patent number: 5317074
    Abstract: An elastomeric orthodonic device such as a ligature, rotation wedge or force module is made of a composition selected from one or more classes of materials, such that the device has certain physical properties useful for orthodontic treatment and also is resistant to staining by common foods and beverages such as mustard, tea and coffee.
    Type: Grant
    Filed: February 7, 1991
    Date of Patent: May 31, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: W. James Hammar, Miriam D. Nave
  • Patent number: 5273559
    Abstract: An abrasive composition and dental articles made from same, the composition including abrasive particles dispersed throughout and entrapped within a polyurea or polyurethane urea matrix which contains soft and hard segments wherein the matrix is made from the polymerization reaction of a polyfunctional amine and a polyfunctional isocyanate. The abrasive dental articles include prophylactic cups and polishing wheels, points and discs.
    Type: Grant
    Filed: December 17, 1992
    Date of Patent: December 28, 1993
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: W. James Hammar, Richard W. Joos
  • Patent number: 4801740
    Abstract: Polymerizable monomer compounds selected from the group having the formulae: ##STR1## whereinR is hydrogen or methyl;X is fluoro, chloro, bromo, iodo, hydroxyl, perfluoroalkylsulfonoxy of one to three carbon atoms, perfluoroacyloxy of one to three carbon atoms, benzoyloxy, or trichloroacetoxy;Y is trichloroacetyl, perfluoroacyl of the formula ##STR2## trialkylsilyl of the formula [CH.sub.3 (CH.sub.2).sub.m ].sub.3 Si-- or hydrogen,wherein n is zero to six; and m is zero to three, with the proviso that when Y in Formula I or II is hydrogen, X is selected from fluoro, chloro, bromo, iodo in Formulas I and II, and additionally from hydroxyl in Formula I, are disclosed. Polymers and copolymers of the invention are useful for preparing hydrogel processed articles such as contact lenses, and when dissolved in solvents they can be coated onto articles and then hydrolyzed to provide hydrogel coatings.
    Type: Grant
    Filed: February 13, 1987
    Date of Patent: January 31, 1989
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: W. James Hammar
  • Patent number: 4786657
    Abstract: A crosslinkable polyurethane or polyurethane/polyurea comprises the reaction product of a composition comprising a macrodiol or macrodiamine, 2-gl;yceryl acrylate or 2-glyceryl methacrylate, a diisocyanate, and optionally a small glycol or small diamine as chain extender. The performance properties of the polyurethanes and polyurethane/polyureas can be controlled by adjustment of the crosslink level and/or curing parameters.
    Type: Grant
    Filed: July 2, 1987
    Date of Patent: November 22, 1988
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: W. James Hammar, John S. Staral
  • Patent number: 4786446
    Abstract: A process for preparing shaped articles and shaped hydrogel articles including ophthalmic devices comprises the steps of preparing a polymer or copolymer comprising units derived from an ethylenically-unsaturated monomer bearing at least one trihaloacetoxy-substituent group, thermoforming said polymer by heating in a mold or in sheet-form at a temperature in the range of 100.degree. to 400.degree. C. for about 5 seconds to 15 minutes, and then cooling said polymer, to provide a shaped article, solvolyzing the resulting shaped article to provide a hydroxy-substituted polymeric shaped article, and optionally hydrating said hydroxy-substituted polymeric shaped article to provide a shaped hydrogel article.
    Type: Grant
    Filed: February 26, 1987
    Date of Patent: November 22, 1988
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: W. James Hammar, Ronald F. Ofstead
  • Patent number: 4673539
    Abstract: A process for preparing shaped articles and shaped hydrogel articles including ophthalmic devices comprises the steps of preparing a polymer or copolymer comprising units derived from an ethylenically-unsaturated monomer bearing at least one trihaloacetoxy-substituent group, thermoforming said polymer by heating in a mold or in sheet-form at a temperature in the range of 100.degree. to 400.degree. C. for about 5 seconds to 15 minutes, and then cooling said polymer, to provide a shaped article, optionally, solvolyzing the resulting shaped article to provide a hydroxy-substituted polymeric shaped article, and optionally hydrating said hydroxy-substituted polymeric shaped article to provide a shaped hydrogel article.
    Type: Grant
    Filed: May 17, 1985
    Date of Patent: June 16, 1987
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: W. James Hammar, Ronald F. Ofstead
  • Patent number: 4638040
    Abstract: Polymerizable monomer compounds selected from the group having the formulae: ##STR1## wherein R is hydrogen or methyl;X is fluoro, chloro, bromo, iodo, perfluoroalkylsulfonoxy of one to three carbon atoms, perfluoroacyloxy of one to three carbon atoms, benzoyloxy, or trichloroacetoxy;Y is trichloroacetyl, perfluoroacyl of the formula ##STR2## trialkylsilyl of the formula [CH.sub.3 (CH.sub.2).sub.m ].sub.3 Si--; wherein n is zero to six; and m is zero to three.Polymers and copolymers of the invention are useful for preparing hydrogel processed articles such as ophthalmic devices, and when dissolved in solvents they can be coated onto articles and then hydrolyzed to provide hydrogel coatings.
    Type: Grant
    Filed: May 17, 1985
    Date of Patent: January 20, 1987
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: W. James Hammar
  • Patent number: 4578504
    Abstract: Polymerizable monomer compounds selected from the group having the formulae: ##STR1## wherein R is hydrogen or methyl;X is fluoro, chloro, bromo, iodo, hydroxyl, perfluoroalkylsulfonoxy of one to three carbon atoms, perfluoroacyloxy of one to three carbon atoms, benzoyloxy, or trichloroacetoxy;Y is trichloroacetyl, perfluoroacyl of the formula ##STR2## trialkylsilyl of the formula [CH.sub.3 (CH.sub.2).sub.m ].sub.3 Si-- or hydrogen,wherein n is zero to six; and m is zero to three, with the proviso that when Y in Formula I or II is hydrogen, X is selected from fluoro, chloro, bromo, iodo in Formulas I and II, and additionally from hydroxyl in Formula I, are disclosed. Polymers and copolymers of the invention are useful for preparing hydrogel processed articles such as contact lenses, and when dissolved in solvents they can be coated onto articles and then hydrolyzed to provide hydrogel coatings.
    Type: Grant
    Filed: June 3, 1983
    Date of Patent: March 25, 1986
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: W. James Hammar