Matrix composition for stable microemulsions

摘要

A matrix composition for making a stable microemulsion for an active ingredient includes a C₈-C₁₈ N-alkyl pyrrolidone with little or no N-methyl pyrrolidone, and a water-insoluble organic solvent soluble therein, preferably more hydrophilic than said C₈-C₁₈ alkyl pyrrolidone and with low water solubility.