| 摘要 |
PROBLEM TO BE SOLVED: To prevent the generation of the hairs of an organic coating film on the edge of a formed body which is formed from a blank when the blank is blanked from a metal plate having the organic film layer. SOLUTION: After the metal plate on one side of a base metal 3z of which the organic film layer 3x is formed is blanked into the blank with a punch 1 and when the formed body 1 is formed, blanking is excuted so that, when the metal plate 3 is brought into contact with the punch 1 and blanking is started, the metal plate is blanked so that the angleθformed with the organic film layer 3x which is brought into contact with the punch 1 and a tangent 2 through the cutting edge 1b of the punch in a peripheral part near a cutting edge on the end face of the punch becomes 3-60 deg.. The end face of the punch 1 consists of a flat main part 1a projected from the cutting edge 1b and anular recessed part 1c between the cutting edge 1b and the main part, and the angleθformed by a straight line with which the cutting edge 1b and the end part 1d of the main part 1a are connected and the tangent 2 of the recessed part 1c through the cutting edge 1b is 3-60 deg..
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