Patents by Inventor David I. Richards

David I. Richards 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).

  • Acetylation of lignocellulosic materials
    Patent number: 5608051
    Abstract: This invention relates to a process for the acetylation of lignocellulosic materials (LM) by (a) bringing the LM into the intimate contact with an acetylating agent comprising acetic anhydride at a temperature from 70.degree.-140.degree. C. and (b) bringing the acetylated LM from step (a) into contact with a superheated chemical agent comprising acetic acid and/or anhydride at a temperature above 140.degree. C. so as to reduce the acetic acid or acetic anhydride content of the acetylated LM to below 10% by weight. LM's treated in this manner have excellent dimensional stability.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: March 4, 1997
    Assignee: BP Chemicals Limited
    Inventors: Helen L. Nelson, David I. Richards, Rune Simonson