I was reading this report about the epicuticle, and I have not been able to fully understand this part of the article. Is there anyone who is knowledgeable about hair anatomy and physiology who can interpret this?
"The epicuticle represents a residual of the cuticle cells membrane and has a proteic nature. It is composed by about 25% lipids and 75% proteins, with 12% of cystine, which represents a high content of sulfur. The protein matrix is directed to the hair fiber surface and it is abundant in cysteil groups, near the surface, which are acidulated by fat acids (lipids) Those lipids, involving mainly the 18-methyl eicosanoic acid (about 30Å, or 3 nm), form a hydrophobic region (about 50-70Å, or 5-7 nm). This cuticle hydrophobic aspect is important because hydrophobic materials as silicones, fat alcohols, oils and polymers have great affinity for hydrophobic surfaces and they will not settle on hydrophilic surfaces. As the cuticle surface undergoes abrasion during the washing and drying processes, as well as in the combing, this hydrophobic layer is removed by washing the surface of Layer A. Layer A and their following layers may be oxidized to more hydrophilic layers."