Study on the Desorption of Isovaleric Acid in Garments

This study aimed to develop a method for extending the lifespan of clothes by removing odors, which can replace existing washing and drying methods. The odor of sweat was selected as the target for deodorization, and the components of sweat, such as ammonia, acetic acid, and isovaleric acid, were treated on the fabric in the gaseous state to yield odorous fabric samples for the deodorization experiments. Deodorizing methods such as steam, hot air, silver colloidal solution, fabric deodorant, and UV were selected based on the desorption mechanism and accessibility of daily-life devices. Subsequently, deodorization evaluation was performed via sensory evaluation and quantitative analysis with gas chromatography-mass spectra. The best deodorizing effect of steam was obtained when 50 ml of water was sprayed at a flow rate of 5 ml/min from a 20 cm distance, which was a favorable distance for the action of the water vapor particles. However, the deodorizing effect varied because of the interaction between the wool, cotton, and polyester fabrics contaminated with the odor. In case of the hot-air method, the deodorizing effect did not vary with the wind strength, and the best deodorizing effect in terms of temperature and time was observed at 80 °C for 1 min, which represents a gas-molecule diffusion rate factor. As the substances responsible for the smell of sweat were not related to microorganisms, the UV or silver solution posed negligible deodorizing effect. However, the fabric deodorant expressed its influence by completely covering the odor with a stronger scent. Overall, the combination of steam and hot air effectively reduced the odors to grade 1 or less on all fibers. Therefore, the proposed deodorization method was extremely effective in comparison to the cases that require 7 h to attain level 1 or less when left outdoors. Furthermore, the appearance and electro-conductive performance of the deodorized samples did not vary, and thus, a much longer functional life can be ensured if the deodorization method is applied to maintenance practices for high-functional textiles such as smart clothing.