protection should be used.
This picture of the 3 categories of hair shows how quickly UV light rays can break down hair.
Sunlight and Bleaching:
The physical chemistry of both chemical bleaching and sunlight effects on human hair are described. Recently we have become more aware of the critical involvement of free radical chemistry on both chemical and sunlight oxidative processes for human hair, therefore these effects are included. The beta layers of the cortical lipids with their high density of double bonds with allylic hydrogen atoms are very sensitive to free radical propagation reactions which can degrade the lipids themselves and also lead to protein degradation. Over the past decade our understanding of the biosynthesis and the structures of the melanin pigments has improved greatly; the most current biosynthetic pathway has been added to this Chapter. Initial oxidation reactions remove 18-MEA (this is the protectant waterproofing the hair has) and free lipids from the surface and between cuticle cells.
When metals like iron or copper are present free radical chemistry is increased leading to degradation of lipids and enhanced protein degradation not only at disulfide bonds but even at peptide bonds.
Oxidative cleavage of disulfide bonds inside cuticle cells also occurs. Degradation of disulfide bonds inside cortical cells occurs next as well as degradation of hair pigments. Other amino acid functional groups are attacked and oxidatively degraded.
That is why Olaplex #1 & #2 in the form of a Stand Alone Treatment is important for people that don't color their hair. With Olaplex the damage can be repaired.
ge can be repaired.