METHOD FOR PHOTOCATALYTICALLY RENDERING A SURFACE OF A SUBSTRATE SUPERHYDROPHILIC, A SUBSTRATE WITH A SUPERHYDROPHILIC SURFACE, AND METHOD OF MAKING THEREOF

摘要

The surface of a substrate is coated with an abrasion-resistantphotocatalytic coating comprised of a semiconductor photocatalyst. Uponirradiation by a light having a wavelength of an energy higher than thebandgap energy of the photocatalyst, water is chemisorbed onto the surfacein the form of hydroxyl groups (OH-) whereby the surface of the photocatalyticcoating is rendered highly hydrophilic. In certain embodiments, the surface ofa mirror, lens, or windowpane is coated with the photocatalytic coating toexhibit a high degree of antifogging function. In another embodiment, anarticle or product coated with the photocatalytic coating is disposed outdoorsand the highly hydrophilic surface thereof is self-cleaned as it is subjectedtorainfall. In a still another embodiment, an article is coated with thephotocatalytic coating and, when the article is soaked in, rinsed by or wettedwith water, fatty dirt and contaminants are readily released without resort toadetergent.