Patent ID: 6187719
Filing Date: 2001-02-13
Classification: C01B,C09K

Abstract:
An oil based drilling fluid comprising:a) an oil drilling base fluid,b) one or more organoclays prepared by the reaction of smectite clay and one or more quaternary ammonium compounds having the chemical formula: ##STR7##wherein R.sub.1 comprises a linear or branched aliphatic hydrocarbon group having from 8 to 30 carbon atoms; R.sub.2, R.sub.3 and R.sub.4 are independently selected from the group consisting of (a) R.sub.1 group(s), (b) linear or branched aliphatic groups having from 1 to 30 carbon atoms or a linear or branched aromatic hydrocarbon group having 6 to 30 carbon atoms; (c) ethoxylated groups containing from 1 to 80 moles of ethylene oxide; and (d) hydrogen; and X.sup.31 comprises an anion, andc) one or more castor wax rheological additives,wherein said fluid exhibits less temperature dependent rheological properties at temperatures below 120.degree. F.