Patents by Inventor Shizuo Iwai

Shizuo Iwai 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).

  • Retarder for gypsum plaster and a process for retarding the setting of gypsum plaster by the use thereof
    Patent number: 4218261
    Abstract: A retarder for gypsum plaster is provided which consists essentially of .beta.-hydroxy-.beta.-carboxy-isocaproic acid or a water soluble salt thereof. It has powerful retarding effect toward gypsum plaster and gives a solid product having much better mechanical strength than that encountered when an alkali metal salt of citric acid or powdered glue which are the ordinary set retarders are used. A process for retarding the setting of gypsum plaster by the use thereof, is also provided.
    Type: Grant
    Filed: May 23, 1979
    Date of Patent: August 19, 1980
    Assignee: Ajinomoto Company, Incorporated
    Inventors: Koji Takeuchi, Takashi Zama, Shizuo Iwai