Organophilic clays are clay minerals that have been treated with a quaternary amine to make them oil-dispersible.  Bentonite, due to its unique rheological properties, is the most widely used clay in the oil & gas industry.

Organophilic bentonite is used in oil muds to build rheology for cuttings lifting and solids suspension.  Most often bentonite suspensions are thixotropic.

Organophilic clays are suitable for use in a wide variety of oils and solvents such as diesel oil, mineral oil, alpha olefins, and vegetable oil.

OC-155 is a high performing organophilic clay.  It is often compared to Bentone 155.