摘要 |
Method and manufacture for electrically insulating base material used for perforated plated-through printed circiut panels with a metal core. The method includes applying a radiation-curable layer of insulating material to the preperforated metal core by an electrostatic spray method and precuring by irradiation or heat, coating with a further thin, thermally curable layer of insulating material by electrophoresis, drying the layer by heating and likewise partially curing it so that it is no longer capable of flowing, but yet is still reactive, optionally applying further curable insulating layers, and finally, fully thermally curing the entire coating of insulating material. The coatings obtained are impervious and are of uniform thickness even at the hole walls.
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