To make a coated electrode used for the PALC panel, which can adequately retard degradation of transmittance caused by sputtering, and which does not raise discharged voltage and discharged current even after a long drive.

This bath includes salts as auxiliaries, which include Mg ions and positive ions of which the hydroxide is soluble in isopropanol and water as the component. Then, the bath reduces the deposition quantity of magnesium, because of including soluble hydroxides, while maintaining the effect of magnesium hydroxide for bonding each particle of borides of rare earths to some extent. As a result, the unevenness on the surface of the coated film becomes small, then discharge voltage and discharge current for driving are reduced, and the PALC panel which can maintain discharge voltage constant even after a long drive, can be manufactured.