| 摘要 |
PURPOSE:To inspect a wide coated surface easily in a short time by coloring pinholes by disposing the coated surface of a metallic material as cathode opposite to anode in electrolyte contg. a soln. type electrochromic material such as viologen dye and applying voltage thereto. CONSTITUTION:The electrolytic reduction of the viologen dye which is the formula (R is alkyl or benzyl, X<-> is halogen ion) from colorless di-cationIto insoluble monocation radical II and its deposition in pinhole parts in a red or reddish purple color are utilized. The paint film surface 9 of a metallic material 8 is immersed in electrolyte 10 contg. viologen dye and with the metal 8 as cathode, an electrode 11 is disposed opposite thereto, thence 1-2V voltage is applied from a DC power source 13 therto. The presence or absence of pinholes is detected with an ammeter 14; at the same time, the places contg. pinholes present a red color - reddish purple color, and therefore their location is distinctly known. This color remains for a while even after the removal of the voltage, and can be returned to the original state when reverse voltage is applied after the inspection. |
