The oxidative polymerization dyeing for wool fibers with pPDA/RC model solutions which formulated with the basic components of currently used cream-type oxidative hair dyes was investigated. The species of oxidized dye adsorbed within wool fibers dyed in pPDA/RC model solutions differ from the species in wool fibers dyed with solutions containing oxidative dyes generated by air oxidation in the pPDA/RC mixed solution, indicating that not all oxidative dyes produced in aqueous solutions are dyed. The ratio of oxidation dyes within wool fibers dyed in pPDA/RC model solutions varied slightly depending on the dyeing solution conditions, such as solution pH and pPDA/RC mixing ratio. In the case of the pPDA/RC (1:1) dyeing system, the dye species sorbed onto the fibers differs depending on the pH level of the dye bath. When dyed at pH 8, binuclear and trinuclear dyes, which are coupling dyes of pPDA and RC, adsorbs onto the fibers, whereas when dyed at pH 10, the absorption of trinuclear dye predominates and that of binuclear dye is not observed. These findings suggest that the trinuclear dye generated by the combination of pPDA and RC undergoes oxidative polymerization on the fiber surface and then penetrates into the fibers, unlike the mechanism of trinuclear dye formation in the pPDA alone system. Moreover, in dyeing systems where the mixture ratio of pPDA is higher than the mixture ratio of RC, it was found that the self-oxidative polymerization reaction of pPDA becomes predominant as the amount of pPDA increases and the binuclear and trinuclear dyes of pPDA coexist onto the fibers.

This paper presents an innovative approach for measuring clothing pressure using flexible strain and bending sensors, classifying it as an indirect method that utilizes Kirk’s formula. This method is positioned as a complementary technique that is particularly effective for dynamic regions near bones and joints, where conventional methods often suffer from reduced measurement accuracy. Traditional direct methods, such as air-pack sensors, face limitations in dynamic measurement, including sensor deformation artifacts and slow response times. The proposed method employs a flexible strain sensor to gauge garment elongation and a bending sensor to evaluate the curved surface shape of the body. Clothing pressure was calculated using Kirk’s formula, which incorporates garment tension (derived from the strain and pre-measured material properties) and the body’s radius of curvature. The effectiveness of the method was validated through experiments conducted under both static and dynamic conditions, and the results were systematically compared with those obtained using an air-pack pressure sensor, a widely adopted direct measurement standard. The findings revealed a strong correlation with the traditional method, underscoring the accuracy and practical utility of the proposed indirect method. This study highlights how the proposed method can mitigate the limitations of the direct methods, particularly in dynamic scenarios. While the proposed method shows promise, challenges remain, including the need for pre-measured stress-strain curves and the inability to measure pressure from the garment weight. Future work will focus on overcoming these limitations to further advance the technology for applications in garment design, wearable devices, and medical and welfare sectors.

In the context of sustainability, bio-based polymer composites have attracted considerable attention. Cellulose nanofibers (CNFs) are promising eco-friendly reinforcing fillers; however, their compatibility with conventional hydrophobic polymers is limited by their hydrophilic surface. Herein, we fabricated bio-based polymer composites through a two-step process―surface modification of porous CNF scaffolds followed by impregnation with epoxidized soybean oil (ESO)―to investigate the influence of interfacial compatibility between the filler and the matrix. Vapor-phase silane coupling reactions were successfully applied to the CNF scaffolds without compromising their porous architectures. The resulting surface-modified scaffolds exhibited distinct characteristics depending on the functional groups introduced by the silane coupling agents. Subsequently, the composites based on CNFs and ESO were fabricated via impregnation, and their structures were characterized using scanning electron microscopy. Fractured surface observations revealed that the surface modifications significantly improved the interfacial compatibility between the CNF scaffolds and the ESO thermoset. Surface mechanical properties, including hardness and friction behavior, were also evaluated to clarify the role of interfacial compatibility. These results indicate that surface mechanical properties are strongly influenced by interfacial compatibility, but less affected by the specific interfacial chemical bonding.