Patents by Inventor Rowena R. Landham

Rowena R. Landham 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).

  • Composite membrane
    Patent number: 5137634
    Abstract: A composite sheet comprises a porous inorganic membrane and a microporous inorganic film overlying a surface of the membrane, where the membrane may be an anodic aluminium oxide membrane having an average pore diameter of 5 to 100 nm, and the microporous film is of substantially uniform pore size and substantially free of cracks and pinholes. The film may be formed by applying a colloidal sol of an aluminium alkoxide, or a solution of a polymeric precursor of a titanium oxide, to a surface of the membrane to form thereon a gel layer, and drying and heating the gel to convert it to a microporous inorganic film.
    Type: Grant
    Filed: April 26, 1990
    Date of Patent: August 11, 1992
    Assignee: Alcan International Limited
    Inventors: Ernest P. Butler, Rowena R. Landham, Michael P. Thomas
  • Composite membrane
    Patent number: 4938870
    Abstract: A composite sheet comprises a porous inorganic membrane and a microporous inorganic film overlying a surface of the membrane, where the membrane may be an anodic aluminum oxide membrane having an average pore diameter of 5 to 100 nm, and the microporous film is of substantially uniform pore size and substantially free of cracks and pinholes. The film may be formed by applying a colloidal sol of an aluminum alkoxide, or a solution of a polymeric precursor of a titanium oxide, to a surface of the membrane to form thereon a gel layer, and drying and heating the gel to convert it to a microporous inorganic film.
    Type: Grant
    Filed: April 16, 1987
    Date of Patent: July 3, 1990
    Assignee: Alcan International Limited
    Inventors: Ernest P. Butler, Rowena R. Landham, Michael P. Thomas