Patents by Inventor Sioe-Heng A. Tjoe

Sioe-Heng A. Tjoe 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).

  • Nonaqueous cathodic electrocoat pigment paste
    Patent number: 5145568
    Abstract: An electrodepositable cationic electrocoating bath containing a nonaqueous pigment paste containing organic solvent. The use of an organic solvent in the place of an aqueous solvent minimizes or eliminates foaming in the process of making the pigment paste.
    Type: Grant
    Filed: December 18, 1990
    Date of Patent: September 8, 1992
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Tapan K. Debroy, Sioe-Heng A. Tjoe
  • Cathodic electrodeposition coatings containing a reactive additive
    Patent number: 5066688
    Abstract: An improved aqueous electrocoating composition that contains a reactive additive of the following formula ##STR1## wherein R is an aliphatic hydrocarbon group; finishes formed from the composition have improved cure and chip resistance.
    Type: Grant
    Filed: April 10, 1991
    Date of Patent: November 19, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Tapan K. Debroy, Sioe-Heng A. Tjoe
  • Nonionic surfactant as a pigment dispersant and film build additive
    Patent number: 5035785
    Abstract: Disclosed herein are electrodepositable cationic baths containing nonionic pigment dispersants. These nonionic pigment dispersants are ethoxylated styrenated phenols which allow for increased production capacity and lower VOC. The ethoxylated styrenated phenols are also used as an additive which can increase film build and improve film smoothness.
    Type: Grant
    Filed: February 23, 1990
    Date of Patent: July 30, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Tapan K. Debroy, Ding Y. Chung, Sioe-Heng A. Tjoe, Craig R. Deschner
  • Cathodic electrodeposition coatings containing lead cyanamide as a supplementary catalyst
    Patent number: 4994507
    Abstract: Disclosed herein are cathodic electrodepositable coating baths containing lead cyanamide as a supplementary catalyst. It has been found that using lead cyanamide in conjunction with a primary metal catalyst (e.g. dibutyltin oxide) results in an electrocoat system with superior underbake cure without sacrificing chipping characteristics during overbake cure.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: February 19, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Tapan K. Debroy, Ding Y. Chung, Craig R. Deschner, Sioe-Heng A. Tjoe