
"Teflon" is a DuPont-owned tradename for PTFE.  Slick-50 does
indeed use DuPont Teflon, though some other brands of such
stuff may use imported PTFE of another brand.

"Teflon", being a trade-name, should always by capitalized.

(DuPont disclaims any benefits of PTFE in the oil supply of internal 
combustion engines, BTW.)