Patent ID: 6270707
Filing Date: 2001-08-07
Classification: B29C,B29K,C08J

Abstract:
A manufacturing method of a highly conductive polytetrafluoroethylene sheet, said method comprising the steps of:admixing a paste of polytetrafluoroethylene powder with conductive substance, being 15-50 wt. % of the PTFE, and extrusion lubricant, being 10 to 60 wt. % of PTFE;extruding the admixture into a preform unsintered tube material by a RAM extruder using an extrusion pressure of 70 to 300 Kgf/cm.sup.2 to a thickness of 0.3 to 5 mm,cutting longitudinally at least one place on a circumference of the unsintered tube material, andcalendering the resulting sheetwherein said highly conductive polytetrafluoroethylene sheet is not less than 170 mm in width and the variance of volume resistivity in the longitudinal direction is 10% or less.