DYNAMIC ELECTROKINETIC AND PERMEABILITY ANALYSIS 113 15 •' 10- E _ z • o • -10- N 0 10 2b 3b 4b 5b 6b 7b 80 TIME ( rain ) o CONDITIONER F + CONDITIONER G • CONDITIONER H ] 4.50 4 00- 3.50- • 3.00- v 250 • 2 00- O• 1.50 J 1.00 0 50- o oo 1 04 .urn 2.08 Hm -•"-.•++H++-.-•+:::::: :• + 354 .um 0 10 20 30 40 50 60 70 80 b TIME ( mln ) CONDITIONER F + C•ONDITIONER G :• CONDITIONER H I 3O 25- •5- lO- o o 10 2b 3b 4b 5'0 60 7o 80 C TIME ( mln ) D CONDITIONER F + CONDITIONER G ß CONDITIONER H Figure 6. Zeta potential (a), flow rate (b), and conductivity (c) as a function of time for hair treated with 1.0% w/w solutions of conditioners F, G, and H.

114 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS 20 15- 10- -15- 9,07mV 8.79 mV -12,63mV -12 52mV ,omv 0 • 1'0 15 2'0 25 30 35 40 45 50 55 60 65 70 75 80 85 90 TIME (MIN) 4.5, 4- 1 0.5 0.37 .Um 0.71 .Urn [] 3,56 •m [] 3,27 •rn 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 TIME (MIN) 20 17.5- E 12.5- • 10- --• 7.5 • 5- 2.5- I Conditi .... g ] Sham• 0.1714 l/rain 0,1954 1/rn•n 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 C TIME (MIN) Figure 7. Zeta potential (a), flow rate (b), and conductivity (c) as a function of time for two consecutive applications of Conditioner I and a shampoo. potential and flow rate data indicate that the anionic detergent adsorbed during the treatment desorbs in the rinsing cycle, leaving the surface progressively less negatively charged, probably because of the presence of the residual amounts of cationic agents. Similarly, the permeability data point to a gradual solubilization of the surface deposits