328 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS (a) 20- 15- •' 10- • 5- Z 0- 0 m -5- w -10 -•5-•li•, -20 0 (b) 4.50 4.00- • 3.50- • 3.00- -.._ 8 v 2.50- 2.00 O• • .50- LL 1.00- 0.50- O.OC 0 1'0 2'0 3'0 4'0 5'0 6'0 7'0 TIME ( rain ) [] 1%ShampooG ß 10%ShampooG 80 1 46 urn 10 20 30 40 50 •0 7b 80 TIME ( min ) (C) 30 25- • 20- Q 1o- z o o o o [] 1% Shampoo G ß 10% Shampoo G ß 0 1111 1/min / 0,1198 1/rnin 10 20 30 40 TIME ( rain ) ß / 0.1462 1/min 0.1308 1/rn•n 50 60 7'0 80 [] 1%ShampooG ß 10%ShampooG ] Figure 8. Zeta potential (a), flow rate (b), and conductivity (c) as a function of time for hair treated with 1.0% and 10% solutions of Shampoo G.

SHAMPOO ANALYSIS 329 (a) 20 • 10- E • s- Z 0- O n -5- UJ -10- N -20 0 1 '0 2'0 3'0 4'0 S'0 6•0 7'0 80 TIME ( min ) [] Shampoo H + Shampoo I (b) 4.50 4.00- 3.50- 3.00- 2.50- 2.00- 1.50- 1.00- 0.50- 0,00 0 (C) 30 1•0 2'0 3'0 4•0 5'0 6•0 7'0 80 TIME ( min ) L [] Shampoo H + Shampoo I I 25- (,.) r-, 10- z o 5- •LLL•LU• 0.0837 l/rain [] • [] • 0,0859 1/min 1'0 2'0 3'0 4'0 50 60 70 80 TIME ( min ) [] Shampoo H + Shampoo I Figure 9. Zeta potential (a), flow rate (b), and conductivity (c) as a function of time for hair treated with 1.0% solutions of Shampoos H and I.