Patents by Inventor Michael D. Crandall

Michael D. Crandall 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: 5645938
    Abstract: A retroreflective article 10 includes retroreflective elements 12 partially embedded in a binder layer 14 that comprises a polyester polyurethane polymer. The polyurethane polymer is a reaction product of (i) a polyester polyol that contains an aromatic nucleus and has at least two isocyanate groups bonded non-conjugatively to the aromatic nucleus, and (ii) a polyisocyanate. A retroreflective article that employs a binder layer of this kind demonstrates extraordinary laundering durability under stringent wash conditions.
    Type: Grant
    Filed: September 15, 1995
    Date of Patent: July 8, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Michael D. Crandall
  • Patent number: 5474827
    Abstract: A retroreflective article (100, 200, 300) includes a monolayer of retroreflective elements (120, 220, 320), a binder layer (110, 210, 310), and a compound comprising an aromatic bidentate moiety. The retroreflective elements (120, 220, 320) are partially embedded in the binder layer (110, 210, 310), and the compound is chemically associated with the retroreflective elements (120, 220, 320) to provide extraordinary laundering durability to the retroreflective article (100, 200, 300).
    Type: Grant
    Filed: March 23, 1994
    Date of Patent: December 12, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Michael D. Crandall, Allen L. Griggs, Peter M. Olofson, Taun L. McKenzie, Theresa M. Watschke
  • Patent number: 5424122
    Abstract: The invention relates to a neutral nonionic latex comprising:(a) about 5 to about 70 weight percent of a nonionic polymer comprising polymerized free-radically polymerizable nonionic monomer, based upon the total weight of the neutral nonionic latex, wherein the free radically polymerizable nonionic monomer comprises:(i) about 90 to about 99 percent by weight of nonionic alkyl acrylate monomer; and(ii) about 1 to about 10 percent by weight of nonionic amide monomer; wherein the weight percentages of (i) and (ii) are based upon the total weight of (i) plus (ii);(b) about 30 to about 95 weight percent of an aqueous phase, based upon the total weight of the neutral nonionic latex; and(c) about 2 to about 10 weight percent of a nonionic emulsifier based upon the total weight of the nonionic polymer plus the nonionic emulsifier;wherein particles of the nonionic polymer are stabilized by the nonionic emulsifier and dispersed within the aqueous phase.
    Type: Grant
    Filed: December 9, 1991
    Date of Patent: June 13, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Michael D. Crandall, Robert L. Nelson
  • Patent number: 5316838
    Abstract: A retroreflective sheet comprising a monolayer of retroreflective elements partially embedded in and partially protruding from the front surface of a binder layer and a backing bonded to the back surface of the binder layer wherein the backing is elastic and comprises a highly conformable and deformable nonwoven web comprising melt-blown microfibers having multiple layers of a relatively low modulus material and a high modulus material.
    Type: Grant
    Filed: March 26, 1993
    Date of Patent: May 31, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Michael D. Crandall, Eugene G. Joseph
  • Patent number: 5232838
    Abstract: A culture media device comprised of a body member including self-supporting substrate, and coated on its upper surface with a layer of water-based adhesive composition and a layer of a cold-water-soluble powder, is provided. The culture media device can also include an optional cover sheet, covering at least a portion of the body member, and an air-permeable membrane affixed to the upper surface of the substrate to allow for the growth of aerobic microorganisms. In addition, processes of making and using the culture media device are disclosed.
    Type: Grant
    Filed: December 9, 1991
    Date of Patent: August 3, 1993
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Robert L. Nelson, Michael D. Crandall, Mary S. Ramos