JOURNAL OF COSMETIC SCIENCE 192 hair tresses. The average changes in shine values of hair samples after the shine shampoo treatments are shown in Figure 6. It can be seen that this shine shampoo improved hair shine for all tested hair. Average hair shine indexes of treated hair tresses increased 9.4%, 9.8%, 12.4%, and 8.25%, respectively, for bleached, medium brown, dark brown, and Asian black hairs. The percent reductions in average cuticle angles of hair samples after treatment with this shine shampoo are presented in Figure 7. It is observed that the aver- age apparent cuticle angles of treated hair decreased 17.5%, 12%, 7.5%, and 10.9%, respectively, for bleached, medium brown, dark brown, and Asian black hair. All these changes were statistically signifi cant. The average changes in shine values of hair samples after the shine conditioner treatments are presented in Figure 8. Statistical analysis showed that there was no signifi cant improvement in hair shine after the conditioner treatment for both bleached and Asian black hair samples. ENHANCEMENT IN HAIR SHINE AND SURFACE SMOOTHNESS BY PBEM CONDITIONER Quaternium-91 (Q-91) conditioners with and W/O additional 2% PBEM were used to study its effects on hair shine and smoothness for bleached, blond, medium brown and Asian black hair samples. The compositions of these two conditioners are listed in Table IV. Table III Shine Values and Changes of Asian Black Hair after Commercial Shine Shampoo Treatment Shine value Hair sample Before After Change (%) Tress 1 42.1 47.0 11.5 Tress 2 44.6 47.8 7.06 Tress 3 42.3 46.7 10.3 Average 9.62 ± 2.30 Table I Shine Values and Changes of Blond Hair after Commercial Shine Shampoo Treatment Shine value Hair sample Before After Change (%) Tress 1 6.18 6.76 9.39 Tress 2 6.06 6.43 6.10 Tress 3 6.21 6.60 6.28 Average 7.26 ± 1.85 Table II Shine Values and Changes of Dark Brown Hair after Commercial Shine Shampoo Treatment Shine value Hair sample Before After Change (%) Tress 1 48.2 53.3 10.6 Tress 2 46.9 52.2 11.3 Tress 3 50.3 54.8 8.85 Average 10.25 ± 1.16

2008 TRI/PRINCETON CONFERENCE 193 The average changes in shine values of hair samples treated with these two conditioners are shown in Figure 9. It is interesting to note that the Q-91 conditioner W/O PBEM only improved the hair shine for bleached hair but reduced hair for other type of hair samples. The shine improvement for bleached hair may be attributed to the deposited Figure 6. Changes in average hair shine values after shine shampoo treatment. Figure 7. Change in apparent cuticle angle after shine shampoo treatment. Figure 8. Change in hair shine values after shine conditioner treatment alone.