stability and filtration control to invert emulsion drilling fluids the product comprises a blend of a carboxylic acid terminated polyamide with distilled and processed tall oil fatty acids and or distilled and processed tall oil resin acids the product is extremely effective even at temperatures as high as 350 u00b0 f decreasing by about two thirds the amount of emulsifier generally required to formulate an effective drilling fluid the product also greatly reduces and in many cases eliminates the need for conventional fluid loss additives and additionally provides electrical stability moreover the product has a pour point as low as about 20 degrees fahrenheit with minimal solvents thereby eliminating the need to ship large amounts of inert material for use and may be transported in a highly active state application_number US 4647305 A description the product of the invention comprises a blend mixture or a combination hereinafter u201c blend of a wetting agent u201c component u2018 a u2019 u201d which is preferably carboxylic acid terminated polyamide and distilled and processed tall oil fatty acids and or distilled and processed tall oil resin acids u201c component u2018 b u2019 u201d component a is a wetting agent preferably concentrated i e about 90 active and typically made from the condensation reaction between unreacted and unmodified fatty acids and polyamines the fatty acids and polyamines are reacted in such proportion as to create a u201c partial amide u201d intermediate product having a mole ratio of the reactive acid sites to amine sites ranging from about 0 5 1 to about 0 75 1 and most preferably about 0 6 1 this partial amide intermediate product is diluted with a.