Drilled porous resin base material, and method of manufacturing porous resin base material with conductive drilled inner wall surface

A process for producing a porous resin base with the inner wall surfaces of perforations made conductive, which comprises the following Steps I to VI:

• (1) Step I of impregnating the porous structure of a porous resin base including both surfaces thereof with a soluble polymer or paraffin, or a compound capable of forming a solid substance by a chemical reaction;
• (2) Step II of forming a solid substance from the soluble polymer or paraffin, or the compound capable of forming a solid substance by a chemical reaction, which has been impregnated, to form a composite sheet of a structure that both surfaces of the porous resin base have a layer of the solid substance, and the solid substance is impregnated into the porous structure;
• (3) Step III of forming a plurality of perforations extending through from the first surface of the composite sheet to the second surface in the composite sheet;
• (4) Step IV of applying a catalyst facilitating a reducing reaction of a metal ion to the surfaces of the composite sheet including the inner wall surfaces of the respective perforations;
• (5) Step V of removing the solid substance from the composite sheet;
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• (6) Step VI of using the catalyst applied to and remaining on the inner wall surfaces of the respective perforations in the porous resin base to apply a conductive metal to the inner wall surfaces.

A process for producing a porous resin base with the inner wall surfaces of perforations made conductive, which comprises the following Steps i to viii:

• (1) Step i of laminating, as mask layers, porous resin layers (B) and (C) on both surfaces of a porous resin base (A) to form a laminate of a 3-layer structure;
• (2) Step ii of impregnating the respective porous structures of the laminate with a soluble polymer or paraffin, or a compound capable of forming a solid substance by a chemical reaction;
• (3) Step iii of forming a solid substance from the soluble polymer or paraffin, or the compound capable of forming a solid substance by a chemical reaction, which has been impregnated;
• (4) Step iv of forming a plurality of perforations extending through from the first surface of the laminate having the solid substance within the respective porous structures to the second surface in the laminate;
• (5) Step v of dissolving the solid substance to remove it from the interiors of the respective porous structures;
• (6) Step vi of applying a catalyst facilitating a reducing reaction of a metal ion to the surfaces of the laminate including the inner wall surfaces of the respective perforations;
• (7) Step vii of removing the mask layers from both surfaces of the porous resin base (A);
• and
• (8) Step viii of using the catalyst applied to and remaining on the inner wall surfaces of the respective perforations in the porous resin base (A) to apply a conductive metal to the inner wall surfaces.