Patents by Inventor Chi Shing Yuen

Chi Shing Yuen 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).

  • Production of gold decorative items
    Patent number: 6376104
    Abstract: A process of producing a gold decorative item, including, sequentially producing an alloy of gold, silver, copper and zinc, forming the gold alloy into a specific shape according to the design of the decorative item and polishing the surface of the decorative item so formed, submerging the decorative item in an acid solution and etching its surface to form a scale pattern, submerging the decorative item in an alkaline solution removing unwanted substances formed on the surface during etching.
    Type: Grant
    Filed: December 30, 1999
    Date of Patent: April 23, 2002
    Inventors: Kin Keung Li, Chi Shing Yuen