Texture and Water Absorption Behavior of Clothing treated with Silicone Fabric Softener

As the softening agent of fabric softeners, dialkyl-type cationic surfactants (e.g. Triethanolamine-based esterquats (TEQ)) are widely used in the market. Meanwhile, silicones have also been applied in order to achieve new textures and functions. Compared with TEQ, silicones have different physicochemical properties, allowing them to impart a “smooth & dry” texture onto clothing. Additionally, although there is often a trade-off between softness and water absorbency, the silicone-type softener does not decrease water absorbency of clothing. In this study, we clarified the surface properties and the adsorption state of each softening agent, and analyzed the different mechanisms on their texture while considering both dry and wet conditions.
In terms of frictional properties relevant to texture, we evaluated the surface viscosity of the softener-treated clothing under low load conditions in order to exclude the effect of textile structures. The results showed that the silicone-type softener exhibited the lowest surface viscosity on clothing under both dry and wet conditions, suggesting that the silicone reduced the adhesion factor when clothing and skin came into contact (Fig. 1). Under wet conditions, the film of TEQ increased its viscosity by contacting with water, whereas the silicone maintained its low viscosity on clothing because of no miscibility with water. Furthermore, the texture under wet conditions was associated with water absorption behavior into clothing. Specifically, it was found that the silicone-type softener increased the water absorption rate of clothing induced by the adsorption of the silicone with other components as a complex on cotton (Fig. 2).
Hence, it was demonstrated that the clothing treated with the silicone-type softener absorbed water quickly and low surface viscosity was maintained even under wet conditions. These factors may lead to relieve the “clingy” texture caused by sweat in clothing, thereby manifesting the "smooth & dry" texture all day long.