Oil - based drilling fluid with copolymers of styrene, (meth) acrylates of bisphenol a - alkoxylates and (meth) acrylic acid

摘要

Oil - based drilling fluid consisting of an oil, an additive for the reduction of losses of liquid and, optionally, further additives, wherein the additive for the reduction of losses of liquid is a copolymer consisting of 50% to 90% of styrene, 10% to 50% (meth) acrylates of bisphenol a - alkoxylates and 0% to 10% (meth) acrylic acid.