| 摘要 |
PROBLEM TO BE SOLVED: To provide a window sash capable of obtaining both of photocatalyst decomposition activity and a photocatalytic hydrophilicity function even when a thick coating film with a certain thickness is applied for reducing degradation of an enamel coating surface or a clear coating surface.SOLUTION: A photocatalyst layer formed on a base material surface is obtained by applying and then drying a coating liquid for window sashes. The coating liquid for window sashes includes photocatalytic metal oxide particles, silica particles and a curable silicone emulsion. The silica particles are partially coated or modified by silane having hydrophobic groups and/or silicone having hydrophobic groups. After applying and then drying the coating liquid for window sashes on the base material surface, by the photoexcitation reaction of the photocatalytic metal oxide particles, at least a part of the hydrophobic groups is replaced with a hydroxyl group, and consequently, the photocatalyst layer surface shows hydrophilicity in the window sash. |
