Patents by Inventor David E. Heyer

David E. Heyer 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).

  • Vacuum pinning process
    Patent number: 4783304
    Abstract: A process improvement for preparing thermoplastic polymeric film, preferably of polyethylene terephthalate, by extruding a web in melt form onto a quench drum with a surface roughness of at least 3 microinches. In casting webs of less than about 5 mils in thickness the improvement involves drawing the melt to a melt drawdown ratio of less than about 25 and spacing the die lips from the quench roll at less than about 120 mils, preferably 20 to 80 mils. It is also preferred that the flow stability index be greater than 5.
    Type: Grant
    Filed: June 17, 1987
    Date of Patent: November 8, 1988
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: David E. Heyer
  • Vacuum pinning of molten thermoplastic film to a roughened casting roll
    Patent number: 4501712
    Abstract: A process is disclosed for increasing the casting speed in manufacturing thermoplastic film and in increasing the quality of film made thereby. The film is cast, in molten form during manufacture, by means of a vacuum, onto a quench roll (casting roll) having a surface roughness of at least 3 microinches (0.08 micrometers).
    Type: Grant
    Filed: August 20, 1982
    Date of Patent: February 26, 1985
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: David E. Heyer
  • Device for uniform web pinning
    Patent number: 4310295
    Abstract: A device for uniform pinning of molten web material onto a quench roll by means of at least two vacuum zones interacting through a baffle, one vacuum zone extending past the line of contact of the web on the quench roll to encompass a portion of the web edge laid onto the casting drum.
    Type: Grant
    Filed: January 28, 1981
    Date of Patent: January 12, 1982
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: David E. Heyer
  • Pneumatic gauge adjustment of edge-pinned cast web
    Patent number: 4255365
    Abstract: A process for promoting uniform thickness in cast webs of thermoplastic material comprising use of variable air forces selectively directed toward a cast web with pinned edges along the line of initial proximity with a quenching surface. Especially useful to mitigate thinning adjacent to the pinned edges.
    Type: Grant
    Filed: January 23, 1979
    Date of Patent: March 10, 1981
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: David E. Heyer
  • Production of a flat thermoplastic film by passing the film over a bearing having a lubricating fluid on the surface thereof
    Patent number: 4017575
    Abstract: In the casting of molten thermoplastic web onto a moving quenching surface, the improvement which comprises passing the freshly extruded web over a bearing having a lubricating fluid on the surface thereof.
    Type: Grant
    Filed: August 16, 1973
    Date of Patent: April 12, 1977
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: David E. Heyer