Two atmospheric pressure plasma jet (APPJ) treatments, APPJ-coating with hexamethyldisiloxane (HMDSO) and APPJ-oxidation, were investigated as soil guard and soil release finishes of textiles. The plainwoven cotton and polyester fabrics were treated by both APPJ treatments and common chemical resins. SEM observation showed that granular particles precipitated on the fiber surfaces after the APPJ-coating. From X ray photoelectron spectroscopy, silicon atoms were detected at the intensity of about half of oxygen after the APPJ-coating, which suggested the silicon oxide, mainly SiO₂, film deposition onto the fiber surfaces would occur. After the APPJ-oxidation, oxygen concentration on the treated polyester fiber surface increased by several % in the spectrum, suggesting the production of polar functional groups on the surfaces. As a result,the sessile drop contact angle on the fabric drastically changed : the APPJ-coating increased the water and oil repellency of both fabrics, and the APPJ-oxidation remarkably reduced the water contact angle on the polyester fabric. Wettability of single fiber determined by the Wilhelmy method suggested that the fiber surface was heterogeneously treated by the APPJ due to the variation in the penetration depth of active species in the plasma jet into the fibrous assembly. Using carbon black and red clay as model particulate soils,their deposition onto the fabrics in the air was investigated. In addition, the soiled fabrics were cleaned in a nonionic surfactant solution with applying stirring action. The deposition of particulate soils and their removal were evaluated by the surface reflectance method. It was found that the APPJ-coating prevented the deposition of particulate soils and the APPJ-oxidation promoted their removal. Comparing with the wet chemical treatment, the APPJ treatment was found to be effective for the deposition and removal control from the viewpoint of the soil guard and release balance.

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The synthesis of biobased poly(ether benzoxazole) (PEBO) derived from natural product vanillin was investigated. Poly(ether o-hydroxy amide) (PEHA) was used as a precursor of PEBO. PEBO was obtained by thermal treatment of PEHA based on the cyclodehydration. Synthesized PEBO was analyzed by Fourier transform infrared spectrometry (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) to confirm the structure and thermal properties. The resultant PEBO film showed flexible and self-standing property. This film also had 5.2 GPa for Youngʼs modulus and 117 MPa for tensile strength which were higher than those of the commercial engineering polymers and other PEBOs.

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We have developed a preparation method of a translucent keratin film in addition to a nonanslucent film. The translucent keratin film was light brown and its surface was smooth by SEM observation. both films were treated with oxidative hair color reagents (dark brown and light brown), color deposit of translucent film was higher than that of the non-translucent film. Interestingly, the color can be easily ured from an absorption spectrum with a spectrophotometer. Thus, we dyed the translucent keratin film the dark brown color reagent under various conditions and analyzed the color deposit by a as a model system. The coloring was depending on the film thickness, the dyeing time, the ncubation temperature, and at lower pH. The formation of cysteic acid was significantly detected, similar to non-translucent keratin film. When the dyed films were immersed in distilled water and tap water, the discoloration by tap water was ster than that by distilled water. The addition of 0.5 mM CaCl₂ to distilled water could induce the color fading. discoloration was also found when the dyed film was exposed to artificial light using a solar simulator. irradiation induced not only a significantly decrease of absorption around the 500 nm but also an increase absorption around the 400 nm, indicating a different hue of the dyed film. The translucent keratin film will be useful to evaluate conveniently the dyeing and discoloration of by dative hair dye reagents

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