... ) for oil drilling fluids Oil Drillling Fluid benton drilling fluid chemical-bentonite clayorganophilic clay (organoclay) for oil drilling fluids Oil Drillling ... viscosity of a certain batch. Bentonite,bentonite clay,bentonite additive,chemical bentonite,Thickener additive,thickener agent,Bentonite thickener,organoclay rheological additive ...