Fig. 4. Maintenance of acidic pH after application of pH 3.5 vinegar, pH 3.5 hydrogen chloride (HCl) and pH 5.0 vinegar cream. Immediately after application of acidic cream, the skin surface pH decreased in pH 3.5 vinegar cream and HCl cream but not in pH 5.0 vinegar cream. Although pH rised after 15 minutes, the slope of increase was gentle, therefore low pH was maintained throughout 6 hours after application of acidic creams.
