| 摘要 |
PROBLEM TO BE SOLVED: To reduce the manufacturing cost of a printed wiring board, by saving the copper resource which comes to nothing, in such a way that the recess of a recessed circuit pattern formed on the surface of a base material is filled up with a mixture of permanent magnet powder and a liquid resin, the mixture is heated after the magnet powder is oriented in the direction of axis of magnetization in a magnetic field, then, nickel particles are scattered on the pattern and oriented in a magnetic field, and the nickel particles are transferred to a substrate and plated with copper. SOLUTION: After a recessed circuit pattern is formed on a base material 1 by using a positive film, the recess of the pattern is filled up with a mixture 2 of an epoxy-based adhesive and permanent magnet powder composed of barium ferrite, and the mixture 2 is hardened in a magnetic field provided with heating plates on the top side and bottom side. Then, nickel particles are evenly scattered on the surface of the hardened mixture 2 after removing deposits and coating the surface with a mold release agent and oriented in a magnetic field in accordance with the pattern. Thereafter, the oriented nickel particles are transferred to a half-dried glass epoxy substrate, by putting the base material 1 on the substrate after the surfaces of the particles are coated with an adhesive composed of an epoxy resin. Finally, a printed board carrying a pattern having a plated thickness of 25μm is obtained by electroless plating the nickel particles with copper after washing the particles with water.
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