Patents by Inventor David J. Lennard

David J. Lennard 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).

  • In-line annealing of sutures
    Patent number: 5587122
    Abstract: We have discovered a process for producing a polypropylene suture including the steps of (a) extruding melted polypropylene resin through an orifice and rapidly quenching the melted polypropylene resin to produce a filament; (b) drawing the filament in the range of from about 5.times. to about 7.5.times. to produce a singly drawn filament; (c) drawing the singly drawn filament in the range of form about 1.times. to about 2.5.times. in a second heated zone being maintained at a temperature in the range of from about 30.degree. C. to about 160.degree. C., to form a doubly drawn filament; (d) shrinking the doubly drawn filament in the range of from about 0.75 percent to about 0.95 percent, in a second heated zone being maintained at a temperature in the range of from about 100.degree. C. to about 180.degree. C., to form a polypropylene suture.
    Type: Grant
    Filed: February 10, 1995
    Date of Patent: December 24, 1996
    Assignee: Ethicon, Inc.
    Inventor: David J. Lennard
  • Pliabilized polypropylene surgical filaments
    Patent number: 4911165
    Abstract: Polypropylene surgical monofilaments sutures of improved compliance are made by drawing polypropylene monofilament to a greater extent than its natural draw ratio, followed by annealing with shrinkage.
    Type: Grant
    Filed: December 12, 1988
    Date of Patent: March 27, 1990
    Assignee: Ethicon, Inc.
    Inventors: David J. Lennard, Edgar V. Menezes, Robert Lilenfeld