Patent ID: 8343370
Filing Date: 2013-01-01
Classification: B29C,B29K,F16J,Y10T

Abstract:
1. A method of fabricating a rotary shaft seal assembly, comprising: providing a rigid annular carrier; providing an annular PTFE seal element having opposite, planar first and second surfaces; providing a vacuum chamber having electrodes therein; placing the first surface of the PTFE seal element on one of the electrodes; drawing a vacuum pressure in the vacuum chamber; introducing a first selected process gas into the vacuum chamber; applying a high frequency signal to the electrodes for a predetermined period of time and producing a discharge plasma from the process gas between the electrodes, the discharge plasma etching and chemically modifying at least a portion of the second surface of the PTFE seal element; purging the vacuum chamber with a second selected process gas and restoring the vacuum chamber to an atmospheric pressure; rinsing the second surface using an acidic solution after the step of etching and chemically modifying at least a portion of the second surface by the discharge plasma absent an intermediate wet chemical etching step between the plasma etching and the rinsing using acidic solution; applying an adhesion promoter to the second surface after the step of rinsing; and attaching the second surface to the carrier after the step of applying the adhesion promoter by molding an elastomer between the second surface and the carrier.