| 摘要 |
PURPOSE:To prevent reduction in the thickness of the part of an electroformed metallic mold corresponding to the part of an electroforming master through which a weaker electric current flows and to improve the durability of the metallic mold by working the part of the master to a shape facilitating electroforming, carrying out electroforming, removing the master, carrying out electroforming again only on the desired part of the resulting metallic mold and finishing the part to the desired shape. CONSTITUTION:An electroforming master 14 is made of epoxy resin, the part 15 of the master 14 through which a weaker electric current flows is built up 23 and an electrically conductive film is formed on the entire surface of the master 14 by a silver mirror reaction. A plated three-layered film consisting of Ni, Cu and Ni layers is formed as usual on the entire surface of the master 14 in separate electroplating cells and the master 14 is broken and removed to obtain an electroformed metallic mold 11. The inside 12 of the mold 11 is then masked 29 with Si or the like except the part 31, electroforming is carried out again on the inside 12 and the resulting raised part 32 is finished to the desired shape by hand to obtain an electroformed metallic mold.
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