Patents by Inventor Kak-Yuen Tao

Kak-Yuen Tao 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).

  • Urea formaldehyde dispersions modified with higher aldehydes
    Patent number: 4332610
    Abstract: A process for the preparation of neutralized, urea aldehyde polymeric dispersions by acid catalyzed reaction of urea and formaldehyde plus a higher aldehyde, having from two to four carbon atoms, wherein the mol ratio of formaldehyde to the higher aldehyde is at least 2:1 and the function of the higher aldehyde is to act as an inhibitor of further polymerization. The dispersions are further stabilized against settling by the addition of thickener-suspending agents. The products of the process are useful as sources of nitrogen which continue to fertilize plants, especially grasses for long periods of time after applied by means of conventional spraying equipment.
    Type: Grant
    Filed: June 3, 1981
    Date of Patent: June 1, 1982
    Assignee: W. A. Cleary Chemical Corporation
    Inventors: Paul Sartoretto, Kak-Yuen Tao
  • Urea formaldehyde dispersions modified with higher aldehydes
    Patent number: 4298512
    Abstract: A process for the preparation of neutralized, urea aldehyde polymeric dispersions by acid catalyzed reaction of urea and formaldehyde plus a higher aldehyde, having from two to four carbon atoms, wherein the mol ratio of formaldehyde to the higher aldehyde is at least 2:1 and the function of the higher aldehyde is to act as an inhibitor of further polymerization. The dispersions are further stabilized against settling by the addition of thickener-suspending agents. The products of the process are useful as sources of nitrogen which continue to fertilize plants, especially grasses for long periods of time after applied by means of conventional spraying equipment.
    Type: Grant
    Filed: April 24, 1980
    Date of Patent: November 3, 1981
    Assignee: W. A. Cleary Chemical Corporation
    Inventors: Paul Sartoretto, Kak-Yuen Tao