research Pengaruh Perbedaan Konsentrasi Propilenglikol terhadap Karakteristik Fisik Hair Tonic Ekstrak Daun Katuk (Sauropus androgynus (L). Merr)
This study found that varying the concentration of propylene glycol in katuk leaf extract hair tonic formulations significantly affects the viscosity, highlighting the importance of propylene glycol concentration in maintaining the physical characteristics of these preparations.

