Patents by Inventor Chu Hwan Cho

Chu Hwan Cho 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).

  • Filter manufacturing method for the production of pre-filters to remove harmful substances in cigarette smoke by use of pine needles
    Patent number: 4636182
    Abstract: A process of manufacturing a pre-filter for the filteration of harmful substances in cigarettes by using pine needles which have been steamed to eliminate the odor of the pine resin. The steamed pine needles then are dried in a shaded lot and formed into powder. A dough is made by mixing up fine powder crushed from the dried pine needles with water. The dough is then crushed into granular form and the pre-filter is obtained by forming the granules into a rod shape.
    Type: Grant
    Filed: August 2, 1985
    Date of Patent: January 13, 1987
    Inventors: Chu Hwan Cho, Gong In Lee