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 comprises: 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).

A first embodiment of the present invention provides a flexible printed circuit board (FPCB) comprising a hot melt adhesive layer and a metal foil layer sequentially stacked on an insulating layer made of a PCT film; a flexible copper clad laminate (FCCL) having a circuit pattern on the metal foil layer; a coverlay adhered to the hot melt adhesive layer formed on the insulating layer made of the PCT film while covering the metal foil layer and also provides a method of manufacturing the FPCB. A second embodiment of the present invention provides an FPCB having a pressure-sensitive adhesive layer instead of the hot-melt adhesive layer, and a method for manufacturing the FPCB having the same, and the third embodiment of the present invention provides an FPCB having a UV cured layer instead of a hot melt adhesive layer, and a method for manufacturing the FPCB having the same.

A resin film according to one aspect of the present invention is a resin film having polyimide as a main component, the resin film including a modified layer formed in a depth direction from at least one side of the resin film; and a non-modified layer other than the modified layer, wherein a ring-opening rate of an imide ring of the polyimide in the modified layer is higher than a ring-opening rate of an imide ring of the polyimide in the non-modified layer, and an average thickness of the modified layer from the one side of the resin film is greater than or equal to 10 nm and less than or equal to 500 nm.

A manufacturing method for a printed circuit board includes: transferring roughness of a metal film to an insulating layer by laminating the metal film on the insulating layer, the metal film having the roughness formed on one surface thereof and having a discrete metal layer laminated thereon; exposing a surface of the insulating layer, on which the roughness is transferred, by removing the metal film; processing the surface of the insulating layer having the roughness formed thereon with an acidic solution; and forming a circuit pattern on the insulating layer by a plating process.

A method of regenerating an etch solution comprising a metastable complex of manganese(III) ions in a strong acid is described in which at least a portion of the manganese(III) ions in the metastable complex have been destabilized, causing them to disproportionate into manganese dioxide and manganese(II) ions. The method includes the steps of i) adding an effective amount of a reducing agent to the solution; ii) allowing the reducing agent to react with the solution to cause manganese dioxide to dissolve; and (iii) applying an electrical current to regenerate manganese(III) ions in the solution.

A stacking structure is applicable to manufacturing a circuit board. The stacking structure includes a transferring layer and a dielectric layer disposed on the transferring layer. The transferring layer includes a substrate and a thin film disposed on the substrate and having a plurality of recess structures thereon. The recess structures are connected as a single piece and bottom portions and top portions of the recess structures are configured to arrange in a staggered manner to form a multi-dimensional arrangement. At least a portion of the dielectric layer being is located in the recess structures, such that the dielectric layer is at least embedded with the recess structures.

An insulated heat dissipation substrate including: a ceramic substrate; and a conductor layer bonded onto at least one of main surfaces of the ceramic substrate, wherein the conductor layer includes: an upper surface; a lower surface; and a side surface 1 connecting the upper surface with the lower surface; the ceramic substrate includes: a lowest portion; a side surface 2 connecting the lowest portion with the side surface 1 of the conductor layer; and a bonding surface at a position higher than the lowest portion, the bonding surface being bonded to the lower surface of the conductor layer; an absolute value (||) is 20 or less on average; and the side surface 1 has a receding portion from an end of the upper surface in the normal direction relative to the tangential line of the contour of the conductor layer as viewed in plane.

A wiring board is disclosed. The wiring board includes a substrate including a first element, a diffusion layer in contact with the substrate and including a first metal element, and a first metal film in contact with the diffusion layer and including a second metal element. The diffusion layer has at least a region including the first element and the first metal element and a region including the first metal element and the second metal element. A concentration of the second metal element in the diffusion layer may decrease as it approaches the substrate in a depth direction. A concentration of the first element in the diffusion layer may decrease as it approaches the first metal film in the depth direction.

A method for selective metallization includes: selectively adsorbing catalytic nanoparticles onto an imprint mold to form a selectively adsorbed catalytic nanoparticle (SACN) mold; using the SACN mold in an imprinting process to synchronously transfer a pattern and the catalytic nanoparticles onto a film; separating the film from the SACN mold; and selectively depositing metal onto the film based on the pattern transferred to the film.

A printed circuit board includes an insulating layer having a first surface and a second surface opposing the first surface; and a first wiring including a first line pattern disposed on the first surface of the insulating layer, and a plurality of first protruding patterns penetrating a portion of the insulating layer from the first surface and connected to the first line pattern, respectively, such that the plurality of first protruding patterns overlap the first line pattern in a plan view of the printed circuit board.