Recently hair coloring and permanents for children have become more common, thus the problem of hair damage occurs. This study collected untreated, colored and permed samples of hair from women in the growth period and the maturity period. They were t...
Recently hair coloring and permanents for children have become more common, thus the problem of hair damage occurs. This study collected untreated, colored and permed samples of hair from women in the growth period and the maturity period. They were then compared to find the change of color, strength, the coefficient of expansion, and thickness. The results of this study are as fellows.
1) Women's hair in the maturity period had an increase in thickness, strength, and the coefficient of expansion as compared with the growth period. There was no difference in color.
2) The change of hair color by coloring was not significant in the maturity period, but hairs were changed in the growth period more than in the maturity period, and all of L, a, and b were increased.
3) In the maturity period, hair strength was greatly changed by coloring, and the coefficient of expansion was much higher in the growth period.
4) The thickness of hair treated with permanent chemicals became thicker when using cysteine than thioglycol, and it was higher in the growth period than in the maturity period by 0.6%.
5) The tensile strength of hair treated with permanent chemicals decreased, and the coefficient of expansion increased in both the growth period and the maturity period respectively.
6) Comparing colored hair with permed hair in the growth period, the tensile strength of cysteine was lower, and its coefficient of expansion was greater.
7) Comparing colored hair with permed hair in the maturity period, the tensile strength of thioglycol was lower, and its coefficient of expansion was greater in the End coloring and cysteine.