Patents by Inventor Richard L. Provost

Richard L. Provost 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).

  • High heat resistant oil-impregnatable electrical insulating board
    Patent number: 4886578
    Abstract: A process for making a high heat resistant oil-impregnatable insulating board, having a dielectric constant less than 2.7, made from bleached polytetrafluoroethylene floc and aromatic polyamide fibrids and the resulting insulating board are disclosed.
    Type: Grant
    Filed: August 30, 1988
    Date of Patent: December 12, 1989
    Assignee: E. I. Du Pont De Nemours and Company
    Inventors: Gary L. Hendren, Richard L. Provost, Kim L. Fried, Leland A. Taylor
  • Pressboard and process for its preparation
    Patent number: 4752355
    Abstract: High temperature resistant pressboard having a desirable combination of compression set values and oil absorption is prepared by a process whereby a low density pressboard is first prepared by forming a wet lap of multiple layers of a waterleaf containing 50-95% by weight water and pressing the wet lap at 100-200.degree. C. under a pressure of 10-60 kg/cm.sup.2, drying, ultimately at 270.degree.-320.degree. C. until substantially no further moisture is evolved and finally pressing at 270.degree.-320.degree. C. under a pressure of 8-350 kg/cm.sup.2 and optionally cooling under restraint.
    Type: Grant
    Filed: July 22, 1986
    Date of Patent: June 21, 1988
    Inventor: Richard L. Provost
  • Co-refining of aramid fibrids and floc
    Patent number: 4472241
    Abstract: An aqueous slurry of 0.2 to 2.0 weight percent aramid fibrids and aramid floc in a weight ratio of 0.25 to 20, respectively, is refined in a disc refiner having grooved facing plates with surface dams, the distance between the facing plates being 0.20 to 1.0 mm.
    Type: Grant
    Filed: June 15, 1983
    Date of Patent: September 18, 1984
    Assignee: E. I. Du Pont De Nemours and Company
    Inventor: Richard L. Provost
  • Dyeing of high strength, high modules aromatic polyamide fibers
    Patent number: 4144023
    Abstract: High strength, high modulus aromatic polyamide fibers are dyed by crimping the fibers while wet to at least 10 crimps per inch and maintaining at least 15% by weight moisture based on the dry fibers in the fibers at all times before dyeing.
    Type: Grant
    Filed: October 11, 1977
    Date of Patent: March 13, 1979
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Richard L. Provost