Patents by Inventor Nien-Shi Chang

Nien-Shi 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).

  • Patent number: 5959003
    Abstract: The present invention provides particulate aqueous polyurethane dispersions and a process for producing the same. Two diverse polyols are reacted with two different amount of hydrophilic group-containing dihydric alcohols to obtain a hydrophobic prepolymer and a hydrophilic prepolymer respectively, and the two prepolymers obtained are together dispersed in water. After chain-extending the dispersed prepolymers, core-shell aqueous polyurethane dispersions are produced, wherein the shell is made from the hydrophilic prepolymer and the core is made from the hydrophobic prepolymer. The polyurethane product made from the aqueous polyurethane dispersions of the invention has superior solvent resistance and can be employed in industrial coating or surface treatment of leather or textiles.
    Type: Grant
    Filed: August 19, 1997
    Date of Patent: September 28, 1999
    Assignee: Industrial Technology Research Institute
    Inventors: Huey-Huey Lo, Yi-Hung Jan, Huey-Zong Wen, Wen-Jiunn Chen, Nien-Shi Chang