| 摘要 |
<p>An oil-based well-working fluid comprising a) an emulsifier comprising the reaction product of i) one or two moles of an amide-amine or a hydroxyalkyl amide (herein defined as component i); with ii) one to five moles of a dicarboxylic acid or an acid anhydride [preferably an acid anhydride] (herein defined as component ii); b) a hydrocarbon drilling oil; and c) a sodium, calcium or magnesium brine.</p> |
