Thermal modulation and airflow distribution determine hair drying efficiency, moisture behavior in human hair in Republic of Korea: an ex vivo study
- Author:
Tae-Rin KWON
1
;
Doohyun HAN
;
Hyoung Jun KIM
;
Jungwook KIM
;
Byung Ho YOON
;
Sung Yong PARK
;
Jun-Seok LEE
;
Na Mi BYUN
;
Jungkwan LEE
;
Jungwon LEE
;
Kwang Ho YOO
Author Information
- Publication Type:Original article
- From: Medical Lasers 2026;15(1):69-76
- CountryRepublic of Korea
- Language:English
-
Abstract:
Background:Hair drying is a routine cosmetic practice; however, excessive heat exposure and non-uniform airflow can compromise cuticle integrity, degrade hair sensory properties, and induce scalp discomfort. This study aimed to (i) identify a practical thermal window that minimizes perturbation of hair fiber surface and quantify late-stage thermal amplification during the drying process using percentage-based analysis.
Methods:Temperature-dependent hair fiber surface morphology was examined by scanning electron microscopy (SEM) after controlled exposure to 41°C, 60°C, 80°C, and 90°C using virgin and chemically damaged hair. The drying efficacy was assessed using the surface and internal moisture indices under airflow shaping (test) and uniform airflow (control) conditions. Hair fluttering (maximum angular displacement) was evaluated before and after drying under warm-cool alternating (60°C-80°C) versus constant hot airflow (80°C).
Results:SEM revealed temperature-dependent cuticle disruption, with markedly greater surface perturbation at 90°C than at 80°C. Infrared thermography demonstrated pronounced late-stage thermal amplification: at 150 seconds, the surface temperature increased by 295% (from 24.2°C to 72.0°C) at 90°C, compared with 207% (from 24.2°C to 50.7°C) at 80°C. Airflow shaping promoted preferential surface moisture removal (–13.6%) while limiting internal dehydration (–9.4%), whereas the control condition exhibited minimal surface drying (–4.6%) but substantial internal moisture loss (–22.2%). Warm-cool modulation increased hair fluttering by +11.0%, whereas constant hot airflow reduced it (–3.7%).
Conclusion:These findings indicate that spatial and temporal control of heat delivery represents a clinically relevant design strategy beyond the nominal temperature specification in hair-drying devices.
