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Updated: Sep 3, 2025
06:39
A High Performance Impedance-based Platform for Evaporation Rate Detection
Published on: October 17, 2016
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Learning from hair moisture sorption and hysteresis
Steven Breakspear1, Patrick Frueh1,2, Anna Neu1
1KAO Germany GmbH, Darmstadt, Germany.
International Journal of Cosmetic Science
|July 27, 2022
Summary
Human hair
Area of Science:
- Materials Science
- Biophysics
- Textile Science
Background:
- Human hair's structure influences its properties.
- Moisture sorption and desorption are key to understanding hair's behavior.
Purpose of the Study:
- To analyze moisture sorption and desorption in human hair.
- To correlate these processes with hair structure and chemical treatments.
Main Methods:
- Recording moisture sorption-desorption isotherms for untreated and treated hair.
- Analyzing hair swelling data.
- Proposing a "breaking symmetry" parameter to characterize treatments.
Main Results:
- Hysteresis in sorption is likely due to protein chain mobility and water binding, not capillary condensation.
- Chemical treatments like bleaching and perming alter hair structure, evidenced by "breaking symmetry".
- Two transitions at 30% and 60-70% relative humidity relate to structural changes and water accommodation.
Conclusions:
- Moisture sorption-desorption analysis quantifies cosmetic treatment effects on hair.
- This method provides insights into the hair fiber's structural characteristics.
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