NON-IONIC TENSIDES 347 Table II Capacitance Values (corneometry) in Arbitrary Units [averages, standard deviations, median values, and boxes (25 % and 75 % percentile)] 15 rain M SD Median Box Spreading bath 1.99 9.96 1.5 - 6.4/10.9 Tween 20: 18% 2.10 4.89 1.1 - 1.5/5.9 Tween 20: 47% -3.20 4.51 -2.0 -5.9/0.0 Water -4.54 5.71 -5.7 -8.9/- 1.3 30 min M SD Median Box Spreading bath 12.74 3.88 12.9 10.0/15.4 Tween 20: 18% 0.41 5.08 1.8 -2.6/29.0 Tween 20: 47% -3.72 3.67 -3.5 -7.2/-1.3 Water -4.94 4.27 - 5.2 - 9.0/- 2.1 60 min M SD Median Box Spreading bath 10.47 4.81 10.0 6.7/13.7 Tween 20: 18% 0.90 5.47 1.4 -4.02/2.7 Tween 20: 47% -4.60 2.57 -3.8 -7.0/-2.4 Water -5.97 5.35 -4.5 - 10.4/- 1.2 90 min M SD Median Box Spreading bath 8.22 5.62 9.2 3.1/11.0 Tween 20: 18% 0.12 6.58 1.8 -3.0/5.1 Tween 20: 47% -4.13 3.31 -2.5 -6.5/-1.9 Water -4.65 4.47 -4.8 -7.4/- 1.9 120 min M SD Median Box Spreading bath 7.16 6.47 6.6 2.9/10.0 Tween 20: 18% 0.93 7.68 2.4 -2.0/6.3 Tween 20: 47% -1.65 4.48 -0.6 -9.1/1.8 Water -4.70 4.46 - 3.9 -9.4/0.0 in transepidermal water loss, and therefore in occlusivity, from a spreading oil bath. Gloor et al. could prove an interdependence between the stratum corneum lipids and tenside content and the amount of emollient in bath oils (4-6). Here, a lower tenside content leads to a higher lipid amount after application of a bath oil with emollients. Table III Differences Between TEWL Values 15 min 30 min 60 min 90 min 120 min Tween 20: 18% * * * * + * Tween 20: 47% ] Water Wilcoxon signed-rank test (, = p 0.01, + = p 0.05).

348 JOURNAL OF COSMETIC SCIENCE Table IV Differences Between Capacitance Values (Corneometer) 15 min 30 min 60 rain 90 min 120 min Tween 20: 18% *]* '1'] * *] *]*] ]+ Tween 20: 47% Water Wilcoxon signed-rank test (, = p 0 .01, + = p 0.05). Bath Oils TEWL 1 o -1 -2 -3 g/sqm x h 0 15 30 60 90 120 ß Almond oil -• Tween 20: 18% • Tween 20: 47% -•- Water rnin n = 15 (WI= first washing, W2= second washing) Figure 1. Transepidermal water loss measurement with the Tewameter during the two hours following washing. The data compiled in this work allow the interpretation of an exsiccating effect of water baths and oil baths with a high content of a mild non-ionogenic tenside. Furthermore, baths of this composition lead to an increase in transepidermal water loss in terms of a slight barrier damage. Tenside solutions are not occlusive as oil solutions are. Treatment with solutions containing a high amount of Tween 20 leads to a "dry" sensory feel on the skin surface. In this context, water and the higher tenside content solution showed the least lubricity and the spreading oil the best lubricity. Thus the barrier damage may be partly due to a lack of lubricity during the washing procedure and an abrasion of the barrier lipids. Oil baths with a low share of the non-ionogenic tenside and, even more, spreading oil baths produce an increase in the hydration of the stratum corneum and a decrease in