Human hair is a member of the group of α-keratin fibres, which during their growth from follicles develop very complex structures on the cellular as well as molecular level. The most important components on the cellular level are the cuticle, as outer layer, and the fibre core (cortex). On the molecular level, cortical cells contain partly α-helical intermediate filaments (IF), embedded into an amorphous matrix of IF-associated proteins (IFAPs). These two components are the basis for the standard ‘two-phase’, fibre/matrix composite model for keratin. To assess changes of the structural components a wide variety of methods is available. Concentrating, namely, on the properties of the cortex, effects of cosmetic processes, products, and ingredients may be determined, e.g., by thermal analysis (Differential Scanning Calorimetry - DSC) and/or tensile testing. Aspects of the systematic changes of the primary thermal parameters as well as of tensile modulus (wet) are discussed for bleaching, perm-waving, chemical relaxation, as well as thermal straightening. Special emphasis is placed on the analysis and interpretation of correlations between thermal and tensile parameters, namely, for the case of thermal straightening.
27 Sep 2018
|Title||BACS Personal Care Group & Society of Cosmetic Scientists (SCS)|
|Period||27/09/18 → …|
|Degree of recognition||National event|