Patents by Inventor Donald C. Johnson

Donald C. Johnson 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: 5079162
    Abstract: A method and media for producing bacterial cellulose under agitated culture conditions resulting in sustained production over an average of 70 hours of at least 0.1 g/liter per hour are achieved. A unique reticulated cellulose product is produced using the methods and conditions claimed, and may be in the form of a sheet characterized by substantial resistance to densification and great tensile strength when produced by sheet forming means.Strains of Acetobacter that are stable under agitated culture conditions and that exhibit substantially reduced gluconic and keto-gluconic acids production are described.
    Type: Grant
    Filed: May 19, 1988
    Date of Patent: January 7, 1992
    Assignee: Weyerhaeuser Company
    Inventors: Arie Ben-Bassat, Robert Bruner, Sharon Shoemaker, Yehoshua Aloni, Harry Wong, Donald C. Johnson, Amar N. Neogi
  • Patent number: 4919753
    Abstract: The present invention is a method of bonding a fibrous wet laid nonwoven fabric-like product using bacterial cellulose as a binder. The bacterial cellulose most useful for the invention is the type formed in an agitated culture. Microorganisms of the genus Acetobacter which are genetically adapted to be good cellulose producers under agitated conditions are preferred cellulose producers. From 1-30% of the bacterial cellulose may be added to a water slurry of other sheet forming fibers as a binder. Preferably 20% or less bacterial cellulose is used since higher amounts retard drainage rates significantly. Bacterial cellulose conveys many desirable properties such as excellent hydrophilicity with low air porosity and high tensile index. It may be used in many cases as a total replacement for the latex binders now used for manufacture of nonwoven fabrics. Bacterial cellulose is especially well adapted for the manufacture of pattern bonded sheets.
    Type: Grant
    Filed: January 23, 1989
    Date of Patent: April 24, 1990
    Assignee: Weyerhaeuser Company
    Inventors: Donald C. Johnson, Amar N. Neogi
  • Patent number: 4863565
    Abstract: A method and media for producing bacterial cellulose under agitated culture conditions resulting in sustained production over an average of 70 hours of at least 0.1 g/liter per hour are achieved. A unique reticulated cellulose product is produced using the methods and conditions claimed, and may be in the form of a sheet characterized by substantial resistance to densification and great tensile strength when produced by sheet forming means.Strains of Acetobacter that are stable under agitated culture conditions and that exhibit substantially reduced gluconic and keto-gluconic acids production are described.
    Type: Grant
    Filed: May 19, 1988
    Date of Patent: September 5, 1989
    Assignee: Weyerhaeuser Company
    Inventors: Donald C. Johnson, Amar N. Neogi
  • Patent number: 4861427
    Abstract: A fibrous web product with a surface treatment containing bacterial cellulose and a method of surface treating such fibrous webs. The bacterial cellulose is applied to at least one surface of a fibrous web, to make products such as printing material suitable for magazines or advertisements, by use of conventional paper manufacturing equipment. The bacterial cellulose may be applied singularly or in combination with other materials such as fillers or pigments. Bacterial cellulose applied at relatively low concentrations gives excellent properties of gloss, smoothness, ink receptivity and holdout, and surfaces strength.
    Type: Grant
    Filed: March 10, 1988
    Date of Patent: August 29, 1989
    Assignee: Weyerhaeuser Company
    Inventors: Donald C. Johnson, Amar N. Neogi, Henry A. LeBlanc
  • Patent number: 4269881
    Abstract: A novel carpet material or mat which is characterized by an extraordinary ability to quickly and comfortably discharge any build-up of a static electricity charge on a person who has built up such a charge, say, by walking across conventional carpeting. The novel material is constructed with a backing which has a low dissipation factor and relatively low volume and surface conductivity, with a conductive thread in the pile and with an electroconductive tufting substrate sheet.
    Type: Grant
    Filed: October 18, 1976
    Date of Patent: May 26, 1981
    Assignee: Ludlow Corporation
    Inventors: Donald C. Johnson, Walter L. Burdorf
  • Patent number: 4097666
    Abstract: Natural or modified polysaccharides are dissolved in a solvent system comprising dimethyl sulfoxide and formaldehyde. The solvent system is particularly suitable for dissolving cellulose due to the fact that cellulose is rapidly dissolved under moderate conditions of temperature and pressure. The dissolved polysaccharides are readily recovered from the solvent system by diluting the solvent system with water or a short chain alcohol.
    Type: Grant
    Filed: April 29, 1976
    Date of Patent: June 27, 1978
    Assignee: The Institute of Paper Chemistry
    Inventors: Donald C. Johnson, Myron D. Nicholson