| 摘要 |
PROBLEM TO BE SOLVED: To form a metal oxide layer having optical properties on a substrate without using a solvent and an organometal compound by applying an aq. sol or a sol mixture of a metal oxide on the surface of a cleaned substrate and heating at a specific temp. SOLUTION: The aq. sol or a sol mixture of the metal oxide is obtained by adding a surfactant mixture consisting of 15-30 wt.% anionic surfactant, 5-15 wt.% nonionic surfactant and <=5 wt.% amphoteric surfactant into the aq. metal oxide sol obtained by electrolyzing an aq. metallic salt solution containing 0.3-15% metal oxide at 0-15 deg.C. An optical layer of the metal oxide having 10-300 nm layer thickness and a refractive index of 1.22-2.20 is formed by cleaning the glass, ceramic or metallic substrate with sodium hydroxide, applying the aq. sol or the sol mixture of the metal oxide thereon, drying under heating at 20-70 deg.C for 0.5-10 hr and after that, heat treating at 100-550 deg.C. |
