144 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Treatment Dry %ACL•e d Quat alone Silicone alone (average of all HMWS) Silicone and quat (average of all HMWS) Silicone alone (average of all LMWS) Silicone and quat (average of all LMWS) 64% 76% 77% 50% 57% This is also illustrated in Figure 9B. The quat by itself substantially reduces dry combing load. Both the HMWS and LMWS also improve the dry combing perfor- mance. Interestingly, the reduction in %ACL change for the LMWS, in the presence or absence of the quat, is by and large lower than that of the quat used by itself. However, the reduction caused by the HMWS, either in the absence or presence of the quat, is higher than that of the quat by itself. 1oo q - • o • 60 2 0 250 500 750 1000 1250 1500 1750 Amount Silicon Deposited (•tg Si/g hair) lOO 80- 60 -( 40- I 0 100 200 o B I I I I 300 400 500 600 700 Amount Silicon Deposited (p-g Si/g hair) 100 40- 20- Amount Silicon Deposited (•g Si/g hair) Figure 7. Dry ( 0 ) and wet (O) combing performance of fluid 1 (A), fluid 2 (B), and fluid 3 (C) in presence of the quat. The values shown at x-axis = 0 are the dry (•) and wet (O) combing benefits of the quat in the absence of any silicones. 0 i i i ! 0 100 200 300 400 500 600

SILICONE-QUAT INTERACTIONS 145 80- 60: 40- 20- ß lOO 80- 60- 40- 20- o o 500 lOOO 15 2000 500 1 00 15 0 2000 Amount Silicon Deposited (gg Si/g hair) Amount Silicon Deposited (gg Si/g hair) Figure 8. Dry (A) and wet (B) combing performance of all the fluids (0) and gums/blend (t•) in presence of the quat. The values shown at x-axis = 0 are the combing benefits of the quat in the absence of any silicones. CONCLUSIONS DEPOSITION The amount of deposition of silicone on bleached hair was found to be a linear function of the initial silicone concentration in the solution dip bath. The amount of silicone depositing did not depend on the molecular weight or the type (dimethicone fluids vs dimethiconol gums) of polydimethylsiloxane used however, it was affected by the presence or absence of the quat. Presence of the quat in the dip bath led to increased deposition, up to double the amount, of the siloxane on the hair. 100 80- 60- 40- 20- Silicones with quat ß ß ß Silicones alone Quat alone lOO 0 H•vlWS with & without quat o •O-lO o ß ß 40- 20- 0 Quat alone o % o ß ß ß o o ee LMWS with & without quat i oi• i do Ioo 500 1000 1500 2000 0 500 1 0 15 Amount Silicon Deposited (gg Si/g hair) Amount Silicon Deposited (Hg Si/g hair) Figure 9. Wet (A) and dry (B) combing performance of all the fluids in the presence of (O) and absence (O) of the quat, and of all the gums/blend in the presence (O) and absence (ß) of the quat. The values shown at x-axis = 0 are the combing benefits of the quat in the absence of any silicones.