Patents by Inventor Rong I. Chang

Rong I. Chang 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).

  • Method of making a shoe sole of thermoplastic materials
    Patent number: 5147589
    Abstract: A method of making a shoe sole which includes a midsole layer of soft material and an outsole layer having wear resistance. The midsole layer and the outsole layer are fused together in a mold which has a mold cavity smaller in size than the shoe sole and in proportion to the shoe sole. When the shoe sole is removed from the mold, the shoe sole is distorted due to a foaming of the midsole layer. The outsole layer is softened and is straightened by the midsole layer so that the shoe sole is directly formed without any cutting processes.
    Type: Grant
    Filed: July 2, 1991
    Date of Patent: September 15, 1992
    Inventors: Shui P. Chang, Rong I. Chang