Patents by Inventor David Lee Shafer

David Lee Shafer 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).

  • Polybutene/liquid polydiene hot melt adhesive
    Patent number: 6211272
    Abstract: It has been surprisingly found that certain properties including adhesion strength to smooth surfaces may be improved by making hot melt adhesives from blends comprising a poly-1-butene polymer, a tackifier resin, and from 3 wt. % to 25 wt. % of a liquid or semi-liquid, hydrogenated or partially hydrogenated low molecular weight conjugated diene polymer prepared by anionic polymerization.
    Type: Grant
    Filed: March 12, 1999
    Date of Patent: April 3, 2001
    Assignee: Shell Oil Company
    Inventors: David Lee Shafer, David Romme Hansen, Larry McArthur Kegley, James Robert Erickson
  • Oil gel formulations containing high vinyl content hydrogenated styrene-butadiene-styrene block copolymers
    Patent number: 5925707
    Abstract: This invention provides oil gel compositions which comprise a hydrogenated styrene-butadiene-styrene (SEBS) block copolymer (although other vinyl aromatic hydrocarbons may be used) which has an overall weight average molecular weight of from 30,000 to 300,000, a styrene block weight average molecular weight of from 4000 to 35,000, and a vinyl content of at least 45% by weight (% wt), preferably 45 to 90%, and an oil and, optionally, a polyolefin wax and/or an extender liquid. For every 100 parts by weight of copolymer, there should be at least 900 parts of oil or a mixture of oil and polyolefin wax and/or an extender liquid.
    Type: Grant
    Filed: July 30, 1997
    Date of Patent: July 20, 1999
    Assignee: Shell Oil Company
    Inventors: David Lee Shafer, Glenn Roy Himes, Michael John Modic
  • Sealant formulations containing high vinyl content hydrogenated styrene-butadiene-styrene block copolymers
    Patent number: 5777043
    Abstract: This invention provides sealant compositions which comprise a hydrogenated styrene-butadiene-styrene (SEBS) block copolymer which has an overall weight average molecular weight of from 30,000 to 300,000, a styrene block weight average molecular weight of from 4000 to 35,000, and a vinyl content of at least 45% by weight (% wt), preferably 45 to 90%, and an adhesion promoting resin. For every 100 parts by weight of copolymer, there should be at least 20 parts of adhesion promoting resin.
    Type: Grant
    Filed: March 5, 1997
    Date of Patent: July 7, 1998
    Assignee: Shell Oil Company
    Inventors: David Lee Shafer, Linda Joanne Oliveri, Glenn Roy Himes