Patents by Inventor Berhan Tecle

Berhan Tecle 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 for isolating ultrafine and fine particles and resulting particles
    Patent number: 6372077
    Abstract: A method of making isolated particles including the step of at least substantially encapsulating particles present in a highly dispersed colloidal suspension with an encapsulant material, such that the encapsulated particles remain independent and discrete upon separation from the suspension. Also, independent and discrete particles at least substantially encapsulated with the encapsulant material.
    Type: Grant
    Filed: January 11, 2000
    Date of Patent: April 16, 2002
    Inventor: Berhan Tecle
  • Method for isolating ultrafine and fine particles and resulting particles
    Patent number: 6190731
    Abstract: A method of making isolated particles including the step of at least substantially encapsulating particles present in a highly dispersed colloidal suspension with an encapsulant material, such that the encapsulated particles remain independent and discrete upon separation from the suspension. Also, independent and discrete particles at least substantially encapsulated with the encapsulant material.
    Type: Grant
    Filed: November 3, 1997
    Date of Patent: February 20, 2001
    Inventor: Berhan Tecle
  • Method for isolating ultrafine and fine particles
    Patent number: 5922403
    Abstract: A method of making isolated particles including the step of at least substantially encapsulating particles present in a highly dispersed colloidal suspension with an encapsulant material, such that the encapsulated particles remain independent and discrete upon separation from the suspension. Also, independent and discrete particles at least substantially encapsulated with the encapsulant material.
    Type: Grant
    Filed: March 12, 1996
    Date of Patent: July 13, 1999
    Inventor: Berhan Tecle
  • Organic vehicle and electronic paste
    Patent number: 5326390
    Abstract: An organic vehicle for electronic paste compositions is provided. The organic vehicle contains organo-soluble hydroxyalkyl substituted polysaccharide, a solvent for the polysaccharide, two hydrogen bonding components and inorganic oxide particulates having a surface area of at least 50 m.sup.2 /g.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: July 5, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Berhan Tecle
  • Process for soldering allowing low ionic contamination without cleaning operation
    Patent number: 5052612
    Abstract: A process for soldering a substrate surface which allows low ionic contamination without a cleaning operation which comprises (a) applying a stannous fluoride or eutectic mixture thereof to the substrate surface and (b) applying solder to the flux applied in (a). The stannous fluoride which is relatively inactive below its melting temperature can be applied to the substrate surface and the so treated substrate held for an extended period of time prior to soldering without any harmful effect on the substrate. The process is useful in electronic assembly that would include attachment of components to circuit boards, tinning of circuit boards, pretinning of component leads, connectors etc.
    Type: Grant
    Filed: August 24, 1989
    Date of Patent: October 1, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Berhan Tecle
  • Solder paste formulation containing stannous fluoride
    Patent number: 4941929
    Abstract: An improved solder paste composition suitable for screen or stencil printing with a capability for low ionic contamination after soldering comprising a metal or metal alloy powder, a carrier, and stannous fluoride.
    Type: Grant
    Filed: August 24, 1989
    Date of Patent: July 17, 1990
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Berhan Tecle