... silky luster of mercerized cotton fabrics. It is also used for producing borax , Cymag , formic acid , oxalic acid , phenol , ... etc.. In the petroleum industry, it is used for refining the petroleum products, and in the well drilling mud ... (3 layers pp&pe).5. .Specification of Caustic soda Caustic soda flake 96% 98% 99%Caustic soda solid 96% 98% 99%Caustic soda pearl 99% Chemicals Caustic soda