Patents by Inventor Donald W. Bridges

Donald W. Bridges 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: 4728023
    Abstract: A process for vapor phase soldering of electronic components comprises applying to the surface of a substrate or to the surface of components on such substrate a solder cream comprising 85 to 90% of finely divided solder metal and 10 to 15% of a fluorinated tertiary alkylamine, preferably a perfluorotrihexyl amine, by weight of the sum of the two components, and positioning electronic components on the substrate, with contacts of such components on the solder cream-coated surface. The substrate is placed in a chamber in contact with the boiling vapors of a second liquid fluorinated tertiary alkylamine having a lower boiling point than the fluorinated tertiary alkylamine in the solder cream, preferably perfluorotriamyl amine, in the chamber, and melting the solder metal in the solder cream and fusing the solder joints of the electronic components to form solder joints substantially free of organic residue.
    Type: Grant
    Filed: February 24, 1987
    Date of Patent: March 1, 1988
    Assignee: McDonnell Douglas Corporation
    Inventors: Felix Barajas, Donald W. Bridges
  • Patent number: 4673532
    Abstract: A solder composition or solder cream especially adapted for vapor phase soldering in electronic circuits without formation of organic residues, comprises a major portion of finely divided solder metal and a minor portion of a fluorinated tertiary alkylamine. Preferably, the composition consists essentially of 85 to 90% of solder metal and 10 to 15% of perfluorotrihexyl amine. A small amount of an organic brominated activator such as homocyclohexane, can be added to convert any lead oxide or tin oxide present in the solder metal, to the corresponding bromides, and a small amount of solvent can be incorporated to disperse the activator in the solder composition. The fluorinated amine vehicle of the solder cream is compatible with and dissolves in the perfluorotriamyl amine, commonly used as the heating medium in vapor phase soldering, and the amine vehicle, perfluorotrihexyl amine, can be recovered from the solution by distillation, for reuse.
    Type: Grant
    Filed: January 22, 1986
    Date of Patent: June 16, 1987
    Assignee: McDonnell Douglas Corporation
    Inventors: Felix Barajas, Donald W. Bridges
  • Patent number: 4661173
    Abstract: A soldering composition containing at least 85% and less than 90% by weight of finely divided solder metal and a minor portion of a vehicle for the solder metal, consisting essentially of a rosin-type flux, a thickening agent and a minor portion, about 2 to about 7%, of a fluorinated tertiary alkylamine, particularly a perfluorotrihexyl amine. During vapor-phase soldering, the amine component is washed from the solder composition, leaving solder metal, rosin-type flux and thickening agent, in the remaining composition, the composition at this stage containing about 90% solder metal, and yielding dense solder joints, essentially no solder balls, and minimal residue.
    Type: Grant
    Filed: July 25, 1986
    Date of Patent: April 28, 1987
    Assignee: McDonnell Douglas Corporation
    Inventors: Felix Barajas, Donald W. Bridges
  • Patent number: 3956088
    Abstract: The destruction of developed or undeveloped photographic film in a manner which permits also the recovery of silver and organic components from the film material in which the film is subjected to wet oxidation at high temperature and high pressure in the presence of a wet oxidation catalyst and a silver complexing compound, and then subjecting the liquor from the wet oxidation step to processing to separate the solubilized silver which is freed from the film and to separate components derived from the film material in the liquor that remains.
    Type: Grant
    Filed: May 1, 1974
    Date of Patent: May 11, 1976
    Assignee: Barber-Colman Company
    Inventors: Wayne Martin Fassell, Donald W. Bridges