A wiring board includes a first wiring layer formed on one surface of a core layer, a first insulating layer formed on the one surface of the core layer so as to cover the first wiring layer, a via wiring embedded in the first insulating layer, a second wiring layer formed on a first surface of the first insulating layer, and a second insulating layer thinner than the first insulating layer formed on the first surface of the first insulating layer so as to cover the second wiring layer. The first wiring layer comprises a pad and a plane layer provided around the pad. One end surface of the via wiring is exposed from the first surface of the first insulating layer and directly bonded to the second wiring layer. The other end surface of the via wiring is directly bonded to the pad in the first insulating layer.

The present invention relates to a production of electro-conductive traces on the surface of polymeric articles using laser excitation for the areas to be metallised, followed by activation of the laser-treated areas with a metal salt solution, the article is later rinsed in distilled water, and the activated areas are metallised in the chemical plating bath. The aims of the invention are to produce cost-effective conductive traces of the circuits for the application in 3D moulded interconnect devices, to increase the quality of the circuit traces improving the selective metallization process. An irradiation dose and scanning parameters for the surface excitation are chosen experimentally, provided that a negative static charge appears on the surface of the laser-irradiated areas. The chosen parameters ensure that any surface degradation of the polymer is avoided. The activation solution used in the method is aqueous solution consisting of one chosen salt comprising: silver (Ag), copper (Cu), nickel (Ni), cobalt (Co), zinc (Zn), chrome (Cr), tin (Sn) salt.

A method for manufacturing a flexible printed circuit board in which base sheets composed of Teflon film having heat resistance and low dielectric constant are stacked to prevent loss of a high frequency signal while minimizing dielectric loss due to the high frequency signal and a flexible printed circuit board manufactured by the same are disclosed. The proposed method for manufacturing a flexible printed circuit board comprises a step of preparing a base sheet which is a Teflon film having a thin film pattern formed on one surface thereof, a step of preparing an adhesive sheet, a step of stacking a plurality of base sheets and adhesive sheets, and a step of heating, pressing, and adhering a stacked body in which the plurality of base sheets and adhesive sheets are stacked.

A method for manufacturing a metal-clad laminate sheet including forming a laminate sheet having the thermoplastic liquid crystal polymer film and the metal foil bonded together; and providing the laminate sheet with a heat treatment which satisfies conditions (1) and (2) below: (1) a heat treatment temperature ranges between 1° C. inclusive and 50° C. exclusive higher than a melting point of the thermoplastic liquid crystal polymer film. (2) a time for the heat treatment ranges from one second to 10 minutes.

A wiring substrate includes: an insulating substrate comprising a corner constituted by two adjacent surfaces; wiring located continuously across the corner; wherein on at least one of the two adjacent surfaces, a part of the wiring disposed at an edge located at the corner has a thickness larger than a part of the wiring disposed away from the edge.

A method for manufacturing a flexible printed circuit board in which base sheets composed of Teflon film having heat resistance and low dielectric constant are stacked to prevent loss of a high frequency signal while minimizing dielectric loss due to the high frequency signal and a flexible printed circuit board manufactured by the same are disclosed. The proposed method for manufacturing a flexible printed circuit board comprises a step of preparing a base sheet which is a Teflon film having a thin film pattern formed on one surface thereof, a step of preparing an adhesive sheet, a step of stacking a plurality of base sheets and adhesive sheets, and a step of heating, pressing, and adhering a stacked body in which the plurality of base sheets and adhesive sheets are stacked.

A method of preparing a non-conductive substrate to allow metal plating thereon. The method includes the steps of a) contacting the non-conductive substrate with a conditioner comprising a conditioning agent; b) applying a carbon-based dispersion to the conditioned substrate, wherein the carbon-based dispersion comprises carbon or graphite particles dispersed in a liquid solution; and c) etching the non-conductive substrate. The etching step is performed before the liquid carbon-based dispersion dries on the non-conductive substrate.

An interconnect substrate includes an insulating layer and an interconnect layer formed on a surface of the insulating layer, wherein the surface of the insulating layer has grooves formed therein, the grooves having a meander shape on an order of nanometers in a plan view, and wherein the interconnect layer has anchor portions fitted into the grooves.

An insulating film includes an insulating layer and a surface bonding layer disposed on the insulating layer. The surface bonding layer includes a radical generation element and a coordinate bond element. In the surface bonding layer, a/b is 0.05 or more and 0.35 or less, in which a is an atom content of the coordinate bond element and b is an atom content of the radical generation element.

A novel pretreating liquid for electroless plating which is used simultaneously with reduction treatment after roughening treatment of a filler-containing insulating resin substrate. A pretreating liquid for electroless plating is used simultaneously with reduction treatment when an insulating resin substrate containing a filler is roughened and residues generated on the insulating resin substrate are reduced. The pretreating liquid contains a reducing agent; and at least one selected from the group consisting of ethylene-based glycol ether represented by CmH(2m+1)-(OC.sub.2H.sub.4)n-OH (m=an integer of 1 to 4, n=an integer of 1 to 4) and propylene-based glycol ether represented by CxH(2x+1)-(OC.sub.3H.sub.6)y-OH (x=an integer of 1 to 4, y=an integer of 1 to 3).