摘要 |
<p>A metal-made shaped article, of which aesthetic value is of importance, such as watch cases, is provided with a coating layer of a ceramic composition containing a limited amount of magnesium oxide as an essential ingredient, the balance being silicon dioxide, aluminum oxide, titanium dioxide and the like, and having a limited thickness. The ceramic-based coating layer can be deposited on the substrate surface by a dry process such as ion plating. The substrate article can be provided with excellent protection against abrasion and corrosion by the ceramic-based coating layer without affecting the beautiful appearance of the substrate surface only when the ceramic composition contains the specified amount of magnesium oxide and the ceramic-based coating layer has a specified thickness.</p> |