Abstract: A wiring board includes an electric insulating base material including an incompressible member and a thermosetting member; a first wiring and a second wiring formed with the electric insulating base material interposed therebetween; and a via-hole conductor penetrating the electric insulating base material, and electrically connecting the first wiring and the second wiring to each other. The via-hole conductor includes a resin portion and a metal portion. The metal portion includes a first metal region mainly composed of Cu; a second metal region mainly composed of a Sn—Cu alloy; and a third metal region mainly composed of Bi. The second metal region is larger than the first metal region, and larger than the third metal region.

Abstract: A circuit board includes a core substrate portion, an insulating layer, a second wiring, and a via to be a cured product of a via paste. The via paste has a first latent curing agent and a second latent curing agent, an uncured resin mixture, and a conductive particle. Both a softening temperature of the first latent curing agent and that of the second latent curing agent are equal to or higher than 40° C. and are equal to or lower than 200° C., and a difference between the softening temperature of the first latent curing agent and that of the second latent curing agent is equal to or higher than 10° C. and is equal to or lower than 140° C.

Abstract: A method of manufacturing a reuse paste includes preparing a fiber piece housing paste, producing a filtered recovery paste, and producing a reuse paste. In the preparing of the fiber piece housing paste, a conductive paste including a conductive particle, resin and a latent curing agent, and a fiber piece housing paste including a fiber piece dropping off from a prepreg used for manufacturing a circuit board are prepared. In the producing of the filtered recovery paste, the filtered recovery paste is produced by filtering the fiber piece housing paste, which remains in a paste state, by using a filter. In the production of the reuse paste, the reuse paste is produced by adding at least one of a solvent, resin, and a paste having a different composition from that of the filtered recovery paste into the filtered recovery paste.

Abstract: A method of manufacturing a reuse paste includes preparing a fiber piece housing paste, producing a filtered recovery paste, and producing a reuse paste. In the preparing of the fiber piece housing paste, a conductive paste including a conductive particle, resin and a latent curing agent, and a fiber piece housing paste including a fiber piece dropping off from a prepreg used for manufacturing a circuit board are prepared. In the producing of the filtered recovery paste, the filtered recovery paste is produced by filtering the fiber piece housing paste, which remains in a paste state, by using a filter. In the production of the reuse paste, the reuse paste is produced by adding at least one of a solvent, resin, and a paste having a different composition from that of the filtered recovery paste into the filtered recovery paste.

Abstract: A multilayer wiring board includes an insulating resin layer, wirings laid on their respective opposite surfaces of the insulating resin layer, and a via-hole conductor for electrically connecting the wirings. The via-hole conductor includes metal and resin portions. The metal portion includes first metal regions including a joined unit made of copper particles for connecting the wirings, second metal regions mainly composed of, for example, tin, a tin-copper alloy, or a tin-copper intermetallic compound, and third metal regions mainly composed of bismuth and in contact with the second metal regions. The copper particles forming the joined unit are in plane contact with one another to form plane contact portions, and the second metal regions at least partially are in contact with the first metal regions.

Abstract: A method of manufacturing a reuse paste includes the steps of preparing a fiber piece housing paste, fabricating a filtered recovery paste and fabricating a reuse paste. At the step of preparing a fiber piece housing paste, there is prepared a fiber piece housing paste including a conductive paste having conductive powder and a resin, and a fiber piece taken away from a prepreg to be used for manufacturing a circuit board. At the step of fabricating a filtered recovery paste, the fiber piece housing paste in a paste state is filtered as it is by using a filter and a filtered recovery paste is thus fabricated. At the step of fabricating a reuse paste, at least one of a solvent, a resin and a paste having a different composition from the filtered recovery paste is added to the filtered recovery paste, and the reuse paste is thus fabricated.

Abstract: A method of manufacturing a circuit board includes the steps of preparing a fiber piece housing paste, fabricating a filtered recovery paste, fabricating a reuse paste, sticking a protective film, forming a hole, and filling the hole with the reuse paste. Furthermore, the method includes the steps of forming a protruded portion constituted of the reuse paste, disposing a metallic foil on both sides of a second prepreg to carry out pressurization, heating the second prepreg to cure the second prepreg and the reuse paste, and processing the metallic foil into a wiring pattern.

Abstract: A wiring board includes a plurality of wirings laid via an insulating resin layer, and a via-hole conductor provided for electrically connecting the wirings. The via-hole conductor includes metal and resin portions. The metal portion includes a region made of copper particles, a first metal region mainly composed of tin, a tin-copper alloy, or a tin-copper intermetallic compound, and a second metal region mainly composed of bismuth, and has Cu/Sn of from 1.59 to 21.43. The copper particles are in contact with one another, thereby electrically connecting the wirings, and at least part of the first metal region covers around and extends over the portions where the copper particles are in plane contact with one another.

Abstract: A circuit board includes a core substrate portion, an insulating layer, a second wiring, and a via to be a cured product of a via paste. The via paste has a first latent curing agent and a second latent curing agent, an uncured resin mixture, and a conductive particle. Both a softening temperature of the first latent curing agent and that of the second latent curing agent are equal to or higher than 40° C. and are equal to or lower than 200° C., and a difference between the softening temperature of the first latent curing agent and that of the second latent curing agent is equal to or higher than 10° C. and is equal to or lower than 140° C.

Abstract: A method of manufacturing a reuse paste includes preparing a fiber piece housing paste, producing a filtered recovery paste, and producing a reuse paste. In the preparing of the fiber piece housing paste, a conductive paste including a conductive particle, resin and a latent curing agent, and a fiber piece housing paste including a fiber piece dropping off from a prepreg used for manufacturing a circuit board are prepared. In the producing of the filtered recovery paste, the filtered recovery paste is produced by filtering the fiber piece housing paste, which remains in a paste state, by using a filter. In the production of the reuse paste, the reuse paste is produced by adding at least one of a solvent, resin, and a paste having a different composition from that of the filtered recovery paste into the filtered recovery paste.

Abstract: A method of manufacturing a reuse paste includes the steps of preparing a fiber piece housing paste, fabricating a filtered recovery paste and fabricating a reuse paste. At the step of preparing a fiber piece housing paste, there is prepared a fiber piece housing paste including a conductive paste having conductive powder and a resin, and a fiber piece taken away from a prepreg to be used for manufacturing a circuit board. At the step of fabricating a filtered recovery paste, the fiber piece housing paste in a paste state is filtered as it is by using a filter and a filtered recovery paste is thus fabricated. At the step of fabricating a reuse paste, at least one of a solvent, a resin and a paste having a different composition from the filtered recovery paste is added to the filtered recovery paste, and the reuse paste is thus fabricated.

Abstract: A method of manufacturing a circuit board includes the steps of preparing a fiber piece housing paste, fabricating a filtered recovery paste, fabricating a reuse paste, sticking a protective film, forming a hole, and filling the hole with the reuse paste. Furthermore, the method includes the steps of forming a protruded portion constituted of the reuse paste, disposing a metallic foil on both sides of a second prepreg to carry out pressurization, heating the second prepreg to cure the second prepreg and the reuse paste, and processing the metallic foil into a wiring pattern.

Abstract: Disclosed is a multilayer wiring board having via-hole conductors, the via-hole conductor including a metal portion and a resin portion. The metal portion includes a first metal region which includes a link of copper particles forming a path electrically connecting a first wiring and a second wiring; a second metal region mainly composed of a metal selected from the group consisting of tin, a tin-copper alloy, and a tin-copper intermetallic compound; a third metal region mainly composed of bismuth; and a fourth metal region composed of tin-bismuth solder particles. The link has plane-to-plane contact portions where the copper particles are in plane-to-plane contact with one another. At least a part of the second metal region is in contact with the first metal region. The tin-bismuth solder particles, each surrounded by the resin portion, are interspersed in the via-hole conductor.

Abstract: Disclosed is a multilayer wiring board having via-hole conductors for connecting a first copper wiring and a second copper wiring, the via-hole conductor including a metal portion and a resin portion. The metal portion includes a first metal region including a link of copper particles as a path for electrically connecting the first and second copper wirings; a second metal region mainly composed of at least one selected from tin, a tin-copper alloy, and a tin-copper intermetallic compound; and a third region mainly composed of bismuth. The copper particles forming the link are in plane-to-plane contact with one another. At least one of the first copper wiring and the second copper wiring is in plane-to-plane contact with the copper particles, and the portion where there is such a plane-to-plane contact is covered with at least a part of the second metal region.

Abstract: In a method of manufacturing a circuit board, a conductive paste is filled in a first hole formed on a first prepreg having both sides to which a first protective film is caused to stick so that a first circuit board is manufactured. A fiber piece housing paste obtained by mixing a fiber piece is recovered to obtain a recovery paste; filtration is carried out through a filter; a solvent or the like is added; and a viscosity, a composition ratio or the like is adjusted so that a reuse paste is fabricated. The reuse paste is filled in a second hole formed on a second prepreg having both sides to which a second protective film is caused to stick.

Abstract: A multilayer wiring board having via-hole conductors which electrically connects a plurality of wirings arranged in a manner such that an insulating resin layer is placed between the wirings, wherein: the via-hole conductors each include copper, tin, and bismuth, namely, a first metal region including a link of copper particles in plane-to-plane contact with one another, the link electrically connecting the wirings, a second metal region mainly composed of one or more of tin, a tin-copper alloy, and a tin-copper intermetallic compound, and a third metal region mainly composed of bismuth; at least a part of the second metal region is in contact with the surface of the copper particles, the surface excluding the area of the plane-to-plane contact portion of the link; and the Cu, Sn, and Bi in the metal portion are of a composition having a specific weight ratio (Cu:Sn:Bi).

Abstract: In a method of manufacturing a circuit board, a conductive paste is filled in a first hole formed on a first prepreg having both sides to which a first protective film is caused to stick so that a first circuit board is manufactured. A fiber piece housing paste obtained by mixing a fiber piece is recovered to obtain a recovery paste; filtration is carried out through a filter; a solvent or the like is added; and a viscosity, a composition ratio or the like is adjusted so that a reuse paste is fabricated. The reuse paste is filled in a second hole formed on a second prepreg having both sides to which a second protective film is caused to stick.

Abstract: A wiring board includes a plurality of wirings laid via an insulating resin layer, and a via-hole conductor provided for electrically connecting the wirings. The via-hole conductor includes metal and resin portions. The metal portion includes a region made of copper particles, a first metal region mainly composed of tin, a tin-copper alloy, or a tin-copper intermetallic compound, and a second metal region mainly composed of bismuth, and has Cu/Sn of from 1.59 to 21.43. The copper particles are in contact with one another, thereby electrically connecting the wirings, and at least part of the first metal region covers around and extends over the portions where the copper particles are in plane contact with one another.

Abstract: A multilayer wiring board includes an insulating resin layer, wirings laid on their respective opposite surfaces of the insulating resin layer, and a via-hole conductor for electrically connecting the wirings. The via-hole conductor includes metal and resin portions. The metal portion includes first metal regions including a joined unit made of copper particles for connecting the wirings, second metal regions mainly composed of, for example, tin, a tin-copper alloy, or a tin-copper intermetallic compound, and third metal regions mainly composed of bismuth and in contact with the second metal regions. The copper particles forming the joined unit are in plane contact with one another to form plane contact portions, and the second metal regions at least partially are in contact with the first metal regions.

Abstract: The mounting board has a capacitor-forming sheet made from a valve metal, first and second board-forming structures, first and second electrodes, an extractor electrode, and a conductive polymer. The capacitor-forming sheet has an inner layer and a rough oxide film on at least one face of the inner layer. The first board-forming structure is provided on a face of the capacitor-forming sheet, and the second board-forming structure is provided on another face thereof on a side opposite to the first one. The first and second electrodes are isolated to each other and provided on a surface of at least one of the first and second board-forming structures. The extractor electrode and conductive polymer are provided inside at least one of the first and second board-forming structures. The extractor electrode electrically-connects the first electrode with the inner layer. The conductive polymer electrically-connects the second electrode with the rough oxide film.