DETERMINATION OF REQUIRED HLB VALUE 415 The highest turbidity of liquid paraffi n emulsions is 63.18% when the HLB value was 10.42. The highest turbidity was shown by the CUFO (79.62%) and CUPO (76.58%) emulsions when the HLB value was 14.90. The HF emulsion displayed the maximum turbidity at 7.06 (50.77%). The CJSO emulsion showed the maximum turbidity of 73.40% when HLB was 7.06 and turbidity of 72.6% when HLB = 5.94. The CUFO and CUPO emulsions had the highest turbidity when HLB had the highest value, 14.90. Therefore, CUFO and CUPO needed additional experiments with polysorbate 20 (HLB = 16.70) so that HLB has a value higher than 14.90. From the additional experiments, the CUFO emulsion showed the highest turbidity when HLB = 14.90 in Figure 8A and HLB = 14.75 in Figure 8B. The CUPO emul- sion had the maximum turbidity at HLB = 15.35 in Figure 8A and HLB = 15.40 in Figure 8B. To c onfi rm whether the additional experiments using polysorbate 20 showed the same tendency as the previous experiments, the experiments were conducted using HF and CJSO emulsions. The HF emulsion had the maximum turbidity of 53.22% at an HLB value of 6.30, and CJSO emulsion had the maximum turbidity of 55.88% at an HLB value of 6.30 (Figure 9). Figure 1. Appearance after 1 week storage of liquid paraffi n emulsions. Figure 2. Appearance after 1 week storage of CUFO emulsions.

JOURNAL OF COSMETIC SCIENCE 416 Turb idity meter. The O /W emulsions stored at room temperature for 1 week were used in this experiment. The turbidity measured by the turbidity meter (Lutron) (Figures 10 and 11) showed a similar tendency to that measured by the UV-vis spectrophotome- ter (Figure 6). The maximum turbidities of liquid paraffi n, CUFO, CUPO, HF, and CJSO emulsions were measured at HLB values of 10.42, 14.90, 14.90, 7.06, and 5.94, respectively. Drop let size analysis. The turbidity value in Figure 10 showed the maximum value in the HLB value of the average minimum droplet size (1,2). The lowest mean droplet size of liquid paraffin (137.77 nm ± 1.46 nm), CUFO (138.00 nm ± 1.73 nm), CUPO (123.50 nm ± 3.31 nm), and CJSO (150.60 nm ± 2.88 nm) emulsions were obtained at HLB values of 14.90, 14.90, and 5.94, respectively (Figures 12 and 13). In the m ethod of Orafi diya and Oladimeji (1) required HLB of liquid paraffi n was about 12, but it was 10.42 in this study by the analysis of mean droplet size and turbidity. This is seen as a difference in the molecular weight and structure of liquid paraffi n. Meher et al. (26) reported that required HLB of light liquid paraffi n was 11.80, but Niczinger et al. (2) reported required HLB of liquid paraffi n as 10.0. Figure 4. Appearance after 1 week storage of HF emulsions. Figure 3. Appearance after 1 week storage of CUPO emulsions.