Perpustakaan Digital ITB

Remote, rapid, and ink-free printing/erasure onfabrics has great potential to revolutionize specialized clothingin numerous applications including fashion/aesthetic andsecurityfields, but the construction of such smart fabrics hasnot been realized due to underlying obstacles in obtainingsuitable photoreversible color-switching systems (PCSS). Toaddress this problem, we have prepared TiO2?xnanorods asphotocatalytic and photothermal component. With redox dyesas reversible color indicators and hydroxyethyl cellulose(HEC) as polymer matrix, TiO2?x/dye/HEC-based PCSS iscoated on poly(dimethylsiloxane)-treated cotton fabric. Under365 nm light irradiation, discoloration occurs in 180 s,resulting from the efficient photocatalytic reduction of the dye. On the contrary, when the colorless fabric is irradiated by 808nm light, recoloration occurs in a very short time (?100 s), far lower than the traditional heating mode (30?8 min at 90?150°C). This rapid recoloration should be attributed to the localized high temperature (164.3?184.5°C) induced by photothermaleffect of TiO2?x. Particularly, when TiO2?x/dye/HEC-based PCSS is extended to coat commercial clothes (such as T-shirts),red/green/bluefigures/letters can be rapidly and remotely printed by UV-light pen and then erased by near-infrared light, withhigh cycle stability. Therefore, such rewritable smart fabric represents an attractive alternative to regular clothes in meeting theincreasing aesthetic or camouflage needs.