42 JOURNAL OF COSMETIC SCIENCE Acid red 52 extraction 2.5 2 � 1.5 { 0.5 0 0 0.1 0.5 2 EDTA·2Na concentration(%) 3.5 3 2.5 E C: 2 1.5 .a { 0.5 0 Acid orange 7 extraction 0 0.1 0.5 2 EDTA·2Na concentration(%) Figure 9. Formation of the dye-metal ion complex inside hair treated by the "permanent" acid-type hair color. The amount of the dye extracted by EDTA form hair was monitored. The dotted and hatched columns represent the absorption of dye from hair dyed with a conventional acid-type hair color and "permanent" acid-type hair color, respectively. The elution of acid red 52 and acid orange 7 of conventional acid-type hair color had no dependence on the concentration of EDT A, but that of "permanent" acid-type hair color had dependence on the concentration of EDTA-2Na. Table VII Fluorescent X-ray Analysis of the State of the Aluminum Ion of Dye-Metal Complex Sample Al-Dye Al-Hair-Dye Al-Hair Photon energy (de V) -1.01 -0.19 -0.32 The degree of difference of photon energy between sample and Al2O3 was investigated. Al-Dye, Al-Hair, and Al-Hair-Dye represent a complex of A1Cl3 ·6H2O and acid orange 7 AlC13 ·6H2O, hair protein, and acid orange 7 and A1Cl3 ·6H2O with hair protein, respectively. The K� spectrum of Al-Hair-Dye was different from that of both Al-Dye and Al-Hair. If it was thought that the combination of both states existed, the K� spectrum is supposed to be the same as the K� spectrum of Al-Dye or Al-Hair. However, actually, the Al-K� of Al-Hair-Dye was different from that of both Al-Dye and Al-Hair. It suggests that the aluminum ion of Al-Hair-Dye binds with both acid orange 7 and hair protein. NMR ANALYSIS OF THE STATE OF BOND The NMR spectra of Dye, Al-Dye, and Al-Dye-EDTA are shown in Figures lOA-lOC. Small peaks indicated by arrowheads appear in Figure lOB. In contrast, the small peaks disappear in Figure lOC. These small peaks are considered to result from chelate between

NOVEL ACID-TYPE HAIR COLOR TECHNOLOGY (8) AI-Dye/CD 3 OD (C) Al-Dye-EDT A/CD 3 OD 9.0 8.5 8.0 7.5 7.0 1 H-NMR spectrum 6.5 43 PPM 6.0 Figure 10. The NMR spectra of the Al-Dye complex. Acid orange 7 in CD3OD medium (Dye/CD3OD), the complex of aluminum ion and acid orange 7 in CD3OD medium (Al-Dye/CD3OD), and the complex dissolved by EDTA in CD3OD medium (Al-Dye-EDTA/CD3OD) were respectively analyzed by NMR spectra. Small peaks, which were considered to be the chelate, are indicated by the allowheads. the aluminum ion and acid orange 7. In other major peaks, the aluminum ion was considered to combine with acid orange 7 by an ionic bond. SENSORY EVALUATION The results of sensory evaluation are shown in Figure 11. The result of Test 1 confirmed that the "permanent" acid-type hair color was slightly superior to a conventional acid­ type hair color in terms of its color brightness effect and clearly superior in terms of its one-month longevity effect. The result of Test 2 confirmed that the "permanent" acid­ type hair color for gray coverage was comparable to a conventional oxidative hair color in terms of its color brightness effect and its one-month color longevity effect. The result of Test 3 confirmed that the "permanent" acid-type hair color for fashion shade was slightly superior to a conventional oxidative hair color in terms of its color brightness effect, but its one-month color longevity effect was comparable. The degree of smooth­ ness and shine after one month was superior to that of conventional oxidative hair color. DISCUSSION FORMATION OF DYE-METAL COMPLEX WITHIN HAIR The result of this study indicates that Al-Hair, Al-Dye, and Al-Hair-Dye have different fluorescent X-ray spectra, suggesting that the state of ligand of the aluminum ions is