How Bleach Affects Tensile Strength of the Hair

This sceintific information from chemist C. R. Robbins:

A major side reaction of bleach application and processing on the hair involves the oxidation of cysteine cross links into cysteic acid. This disruption of the bonds in the cortex has a major influence on the WET TENSILE STRENGTH of the hair.. And,the more aggessively the hair is lightened, (bleached) to a "pale yellow", almost white- discoloration. more of the bonds are broken. When hair has been bleached to white, the cuticle is no longer attached.

When dry hair has been overlightened, it does not break easily unless more than 64 percent of the disultide bonds have been broken. So, be EXTRA GENTLE and EXTRA CAREFUL when manipulating, combing or detangling highly bleached hair -- wet or dry!

BONDERS are useful tools when mixed with our salon bleach formula. They help form a temporary BRIDGE of that cysteine "glue" back into the hair, but, these do NOT return the hair to a 100%"virgin" perfectly un-compromised fiber. We must advise highly-lightened clients that use of the bonder's corresponding "at home" condiitioner is required; as it maintains a required level of strength in that hair.

As always, I hope to see you in class. Comment here if you found this information to

be of value. B