Patents by Inventor John E. Larrabee

John E. Larrabee 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).

  • Methyl chloroform-free desmear process in additive circuitization
    Patent number: 5311660
    Abstract: Disclosed is a method of drilling, desmearing, and additively circuitizing a printed circuit board. The printed circuit board is drilled under conditions which produce glass and polymer smeared vias and through holes. The particulate debris is removed by vapor blasting the drilled printed circuit board. Next the printed circuit board is soaked in a solvent to swell the drill smear on the circuit interplanes of the printed circuit board. This solvent is then removed by entrainment in a gas, and a stream of an aqueous, acidic, oxidizing solution is passed through the printed circuit board holes to remove swollen smear in the thru holes and produce an etchback of conductors. After a water rinse an aqueous reducing solution is passed through the printed circuit board to reduce and remove aqueous acidic oxidizing solution, e.g., residual aqueous acid oxidizing solution. The printed circuit board is rinsed to remove the aqueous reducing solution.
    Type: Grant
    Filed: February 10, 1993
    Date of Patent: May 17, 1994
    Assignee: International Business Machines Corporation
    Inventors: Warren A. Alpaugh, Anilkumar C. Bhatt, Michael J. Canestaro, Robert J. Day, Edmond O. Fey, John E. Larrabee