Over the years, many individual studies have been conducted regarding the extent of damage imparted to hair. These studies deal with the damaging effects of various chemical processes such as permanent waves, permanent colors and hair bleaches.
The most commonly employed method to quantify this damage is the measurement of change in tensile properties of the hair. This method takes two to three days in the preparation of samples of hair fibers. It also requires a minimum of 30 to 40 fibers for statistical analysis. Therefore, there is a need for other simpler methods that are equally valid and less time-consuming.
Excerpt Only This is a shortened version or summary of the article that appeared in the Nov. 01, 2002 issue of Cosmetics & Toiletries magazine. The full content is not currently available online.