Luster or shine is an important feature of hair’s appearance and this visual effect is a key objective in the consumer hair care market. Color strength is another important attribute for colored hair but no parameter or test method has previously been developed to combine the two and enable quantified vibrancy claims. In relation, based on work by Lefaudeux et al., in the present article, the authors define a new parameter for such claims, the hair color vibrance factor (HCVF).
Technical Background
Lefaudeux et al. published on principles for measuring hair luster (shine) using a device designed to measure scattering sources on a hair tressa.1, 2 As shown in Figure 1, the researchers indicated two bands that were captured in images of colored hair: the shine band or first reflection with no color; and the chroma band or second reflection with color. From these observations, the researchers defined an overlapping coefficient to describe the overlapping degrees between shine and chroma (see Figure 2 on Page 50). It was also observed that after hair was treated with certain cosmetics, this coefficient increased and corresponded with shinier, richer color.
