Abstract: Bacterial inhibitory performance of blends of p-anisic acid and sorbitan caprylate in hair shampoo was studied by preservation test method. Effect of dosage of the antibacterial agents,as well as the application conditions (pH and temperature of the system) on inhibition result was examined. Results showed that as the mass fraction of the p-anisic acid achieves 0.4% and the sorbitan caprylate achieves 1.0%,as well as the pH keeps no more than 6.0,the system displays good antibacterial performance.

Key words: hair shampoo, p-anisic acid, sorbitan caprylate, antibacterial effect