| 摘要 |
PURPOSE:To improve durability by forming a film on the surfaces of metals such as Al, Fe, Zn or the like with an aq. soln. containing mixed silicates of Na, K, Li consisting of prescribed rates of components at prescribed ratios. CONSTITUTION:The surfaces of Al, Fe, Zn, Sn, Ni, Cu and their alloys are polished to make specular surfaces of >=60% at 60 deg. specular reflectivity. On the other hand, an aq. soln. of mixed alkali metal silicates of (a) part Na2O.lSiO2, (b) part K2O.mSiO2 and (c) part Li2O.uSiO2 is prepd. under the conditions of 2<=l<=7.5, 2<=m<=5, 3<=u<=10, 0.01<=a/(a+b+c)<=0.4, 0.2<=b/(a+b+c)<1, 0<c/ (a+b+c)<=0.5. A film is formed on said metallic specular surfaces with such aq. soln. of the silicates. In this way, the specular surfaces of high durability are obtained. |
