Patents by Inventor Tow P. Liew

Tow P. Liew 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).

  • Cigarette smoke filter
    Patent number: 5190061
    Abstract: A novel cigarette smoke filter element is provided which achieves an increased removal of tar from cigarette smoke while retaining a higher flavor level than is achieved using conventional filter materials. The filter comprises an elongate cylinder of microfine fibers which is closed at the upstream end of the filter element and tobacco smoke filter material located both externally and internally of the cylinder of microfine fibers. A tobacco smoke flow path blocking means is provided at the downstream end of the filter element to permit filtered tobacco smoke to pass from the filter element only from the tobacco smoke filter material located internally of the cylinder of microfine fibers.
    Type: Grant
    Filed: April 19, 1991
    Date of Patent: March 2, 1993
    Assignees: Rothmans, Benson & Hedges Inc., Rothmans International Services Limited
    Inventors: Warren A. Brackmann, Tow P. Liew
  • Cigarette filter rod elements and cigarettes incorporating such filter rod elements
    Patent number: 4972853
    Abstract: A cigarette filter rod element including an axially extending barrier tube of micro-fine fibres with a diameter of between 0.5 and 10 microns and located so that at least part of the gas flow passes through the wall of said barrier tube.
    Type: Grant
    Filed: October 12, 1989
    Date of Patent: November 27, 1990
    Assignee: SK Hand Tool Corporation
    Inventors: Warren A. Brackmann, Tow P. Liew