| 摘要 |
PROBLEM TO BE SOLVED: To impart affinity for vapor or liq. to the surface of a metallic material by immersing a metallic material into a fluorinating agent-contg. aq. soln. to form a metallic fluoride coating film on the surface, then immersing it into a water glass soln., thereafter executing heating to sinter and stick water glass, moreover immersing it into water and eluting sodium in water glass. SOLUTION: As the metallic material to be applied with surface treatment, stainless steel and Al materials are given, but, particularly, stainless steel is preferable. As the fluorinating agent-contg. aq. soln. used for the formation of a metallic fluoride coating film, an aq. soln. contg. fluorine ions and alkali ions is given, and, e.g. the one obtd., by adding an aq. soln. contg. about 0.2 to 20 wt.% alkali fluoride with hydrogen fluoride and controlling its pH to 2.0 to 6.5 is suitable. Moreover, when sintering and sticking water glass, advantageously, the sintering is executed at 200 to 250 deg.C for 5 to 30 min in a furnace capable of homogeneous heating.
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