Patents by Inventor Jisuke Hayashi

Jisuke Hayashi 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).

  • Method of refining woodchips or beating wood pulp with a selectively sulfonated chitosan
    Patent number: 5454907
    Abstract: A refining assisting agent comprising sulfonated chitosan has been provided. With the addition of the sulfonated chitosan according to the present invention, power needed in the refining can be remarkably reduced compared with that needed in the conventional refining. In addition, the refining assisting additive improves paper strength.
    Type: Grant
    Filed: February 15, 1994
    Date of Patent: October 3, 1995
    Assignee: Japan PMC Corporation
    Inventor: Jisuke Hayashi
  • Process for preparing a sulfonated chitosan
    Patent number: 5229504
    Abstract: There is disclosed a process for preparing a sulfonated chitosan wherein C3/C6-position hydroxyl groups are selectively sulfonated with inexpensive sulfonating agents which comprises dissolving or swelling chitosan in an acetic acid in water, regenerating chitosan with an alkaline aqueous solution, washing the regenerated chitosan with water and then with alcohol, immersing the chitosan in a polar solvent and pressing the solvent out of the same and sulfonating the chitosan with SO.sub.3 -DMF complex or ClHSO.sub.3an -DMF complex in a non-polar solvent. Separation of the product can be easily effected by way of filtration and the like.
    Type: Grant
    Filed: September 6, 1991
    Date of Patent: July 20, 1993
    Assignee: DIC-Hercules Chemicals, Inc.
    Inventor: Jisuke Hayashi