Patents by Inventor Tzu L. J. Huang

Tzu L. J. Huang 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).

  • Patent number: 4755425
    Abstract: Retroreflective sheeting has been improved by a coating comprising silica and a transparent polymer selected from aliphatic polyurethanes and polyvinyl chloride copolymers having a minor amount of a comonomer containing at least one carboxylic acid or hydroxyl moiety. Silica comprises 10-80 weight percent of the transparent protective coating. For example, a solution or dispersion of polyurethane is mixed with a silica sol and possibly other ingredients (e.g. wetting agent, UV light absorber and adhesion promoter), and the composition is coated onto the retroreflective sheet and dried. The coated retroreflective sheeting has superior soil and dew repellancy, retaining a higher percentage of original brightness after exposure to dirt and/or dew conditions.
    Type: Grant
    Filed: March 9, 1987
    Date of Patent: July 5, 1988
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Tzu L. J. Huang