ALIGNMENT CONTROL AND SOFTNESS CREATION IN HAIR 27 below the Hookean region and approaching the toe-in region. The subsequent measure- ments of hair physical properties were, therefore, limited to within this range to refl ect the real loads experienced by hair fi bers during everyday consumer manipulation and to study the perceived effects of GG under such conditions. STRESS RELAXATION MEASUREMENTS A typical grooming procedure in which the application of the GG treatment might be used is given in Figure 4. Misaligned and disordered hair (Step 1) are washed and the treatment is applied (Step 2), after which a slight stress is applied to the damp hair (Step 3) to align the bunch (Step 4). The magnitude of this stress directly correlates with the fi nal alignment of the hair bundle the meniscus force arising between fi bers in the wet state is enough to attain a certain degree of alignment (11), although in this study, it has been observed that combing will give greater alignment, in addition to any detan- gling effect. It is preferable that the hair will maintain this alignment to some degree typically, however, the hair will tend to revert to their original state on drying (Step 5), with any improvement in alignment coming from residual water set. Thus, to realize an Table III Rank Responses and Statistical Results for Control Tresses in Perception Tests Judge Unruly hair content of tress (by weight) Straight (0%) 2% 5% 10% 20% 20% + GG A 1 2 5 4 6 3 B 1 2 3 5 6 4 C 1 2 3 4 6 5 D 2 1 3 5 6 4 E 1 2 3 5 6 4 F 1 4 2 6 5 3 G 1 3 4 5 6 2 H 1 2 3 6 5 4 I 1 3 4 5 6 2 J 2 1 3 5 6 4 K 1 2 5 4 6 3 L 1 3 2 6 4 5 M 2 1 3 6 4 5 N 2 1 5 4 6 3 Ri 21 30 50 75 84 55 52.5 S 3009.5 W 0.76 χ2 57.0 R

JOURNAL OF COSMETIC SCIENCE 28 agent’s effectiveness, this irregular nature should be resisted and the aligned state stabi- lized, in a form more closely resembling Step 4. In this study, the effect of GG during the procedure outlined in Figure 4 would thus appear to increase the stability of the align- ment from the wet state to the dry state and to greatly reduce the incidence of irregularly shaped hair visibly “breaking away” from the bundle. To model this behavior, stress re- laxation measurements on single hair fi bers under high humidity conditions were used. Using the upper limit of 0.5% strain, the relaxation characteristics of untreated, control treatment–treated, and GG-treated hair fi bers were studied. Figure 5 shows a stress- transient plot of the averaged relaxation data (N = 10) collected for curly damaged Japa- nese hair fi bers at high ( 95%) relative humidity and normalized against the initial values of stress. The greater relaxation after treatment with the control treatment and, Figure 4. Typical grooming procedure in which the application of a GG treatment might be used. Figure 3. Force meter (A) used to evaluate load per fi ber when hair is gently pulled into alignment (B).