Patents by Inventor Cheng Fan Lo

Cheng Fan Lo 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: 4082743
    Abstract: Dialdehyde cellulose is produced by reacting cellulose in aqueous medium with meta periodate ion used in a molar ratio of from 1.2 to 12 moles of meta periodate ion per mole of cellulose at a temperature of from 36.degree. to 60.degree. C. and a pH of between 2 and the conversion pH of water soluble meta periodate to water insoluble para periodate, and separating the dialdehyde cellulose product from the reaction mixture.
    Type: Grant
    Filed: January 28, 1975
    Date of Patent: April 4, 1978
    Assignee: Boise Cascade Corporation
    Inventors: William Montgomery Hearon, John F. Witte, Cheng Fan Lo
  • Patent number: 4016207
    Abstract: Di- and tricarboxy celluloses are hydrolyzed with sulfurous acid in an aqueous medium to a mixture of erythronic acid and glyoxylic acid, in the case of dicarboxy cellulose; to a mixture of meso tartaric acid and glyoxylic acid in the case of tricarboxy cellulose; and to a mixture of these three products, in the case of a feedstock comprising a mixture of di- and tricarboxy celluloses.
    Type: Grant
    Filed: November 5, 1975
    Date of Patent: April 5, 1977
    Assignee: Boise Cascade Corporation
    Inventors: William Montgomery Hearon, John F. Witte, Cheng Fan Lo
  • Patent number: 3998878
    Abstract: Mixtures of oxalic, meso tartaric, glyoxylic and erythronic acids derived particularly from the oxidation of cellulose derivatives are separated from aqueous solutions in which they are contained and from each other by stepwise precipitation with calcium ion at controlled pH. The oxalic acid is precipitated as calcium oxalate at a pH of 0.9 to 2.0; the tartaric acid as calcium meso tartrate at a pH of 2.8 to 4.4; and the glyoxylic acid, as calcium glyoxylate at a pH of 4.5 to 5.4. After each precipitation the water insoluble precipitate is separated from the aqueous mixture in which it is contained. The relatively soluble erythronic acid remains in solution as a free acid, or in the form of its calcium salt.
    Type: Grant
    Filed: November 5, 1975
    Date of Patent: December 21, 1976
    Assignee: Boise Cascade Corporation
    Inventors: William Montgomery Hearon, Cheng Fan Lo, John F. Witte