Adsorption Characteristics of Vanadium Ion on Wool, and Photothermal Conversion and Heat Transfer of Vanadium-Treated Wool Depending on Humidity

The wool fabrics were treated with VOSO4 aqueous solution and its photothermal conversion and heat retention behaviours were evaluated in comparison with the fabrics of untreated wool, normal polyester and polyester incorporated with zirconium carbide. The adsorption of vanadium ions onto the wool fabric was found to be the Langmuir type. The VOSO4-treated wool fabric showed higher photothermal conversion than the untreated wool fabric, when it was irradiated with the visible/IR light. The temperature of the VOSO4-treated wool single fabric under the light irradiation decreased slightly with an increase in the chamber humidity. The temperature of the single fabric after the light off increased largely with an increase in the chamber humidity. It was considered to be due to the increasing specific heat capacity of the fibre which absorbed and adsorbed water. The surface temperatures of the lighted side and of the back of the lighted side for the four-layered VOSO4-treated wool fabrics were highest among the fabrics of untreated wool, normal polyester and polyester incorporated with zirconium carbide, when they were irradiated with the light at 65 %RH humidity. It was found that the VOSO4-treated fabric is the warmest on the whole, when the same light is irradiated to the four kinds of layered fabrics.