| 摘要 |
PURPOSE:To prevent the rusting of a crown having an exposed cut end formed by blanking by putting the crown and a disoxidant in a tightly sealed vessel. CONSTITUTION:A crown having an exposed cut end formed by blanking after coating and baking is put in a gas impermeable vessel. A disoxidant such as iron powder, iron carbide, a ferrous salt or other reducing substance is also put in the vessel, and the vessel is tightly sealed. By this method the rusting of the cut end of the crown is prevented.
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