Reimagining Hair Science: A New Approach to Classify Curly Hair Phenotypes via New Quantitative Geometrical and Structural Mechanical Parameters
November 2022
curly hair kinky hair coily hair geometric properties mechanical properties scanning electron microscopy photogrammetry optical microscopy texture analyzer dynamic mechanical analyzer stress stretch ratio fiber geometry mechanical performance personal care products SEM microscopy DMA hair stress hair stretch hair products
TLDR New methods to classify curly hair types were developed based on shape and strength.
This research aims to develop a new approach to classify curly and kinky/coily hair phenotypes using quantitative geometric and mechanical parameters, moving beyond traditional and limited ethnicity-based systems. The study involved measuring geometric properties of hair samples with scanning electron microscopy, photogrammetry, and optical microscopy, and mechanical properties using a texture analyzer and a dynamic mechanical analyzer. These methods mimic the act of brushing or combing and measure the force related to displacement, allowing the study of stress and stretch ratio as hair strands uncurl and stretch to the point of fracture. The data showed correlations between fiber geometry and mechanical performance, which will inform the development of personal care products tailored to curly and kinky/coily hair types. This research promotes cultural inclusion and aims to provide a more representative classification system for diverse hair phenotypes.
