抄録
We have successively fabricated the hafnia films hardened by ultraviolet irradiation to pencil hardness of more than 9H. This paper describes the hardening and its processes of sol-gel derived hafnia films containing an organic ligand by UV irradiation. Hafnia sol solutions were prepared by the hydrolysis of hafnium hydroxide with H2O and an oxalic acid in an aqueous solution. The transparent gel films were hardened after UV irradiation using a high-pressure mercury lamp at a power level of 80 mW/cm2. The gel film was hardened to more than 9H after UV irradiation of 2.5 min. The films showed water droplet contact angles of about 90°, indicating that the hardened films showed hydrophobicity. Hardening processes of the film was investigated by temperature programmed desorption (TPD) and FT-IR. The TPD analysis of the film showed that the amount of the oxalic ion decreased after UV irradiation.
