Abstract: There is provided a roughened copper foil which can significantly improve adhesion to an insulating resin and reliability (e.g., hygroscopic heat resistance). The roughened copper foil of the present invention has at least one roughened surface having fine irregularities composed of acicular crystals, wherein the entire surface of the acicular crystals is composed of a mixed phase of Cu metal and Cu2O.

Abstract: There is provided a roughened copper foil which can significantly improve adhesion to an insulating resin and reliability (e.g., hygroscopic heat resistance). The roughened copper foil of the present invention has at least one roughened surface having fine irregularities composed of acicular crystals, wherein the entire surface of the acicular crystals is composed of a mixed phase of Cu metal and Cu2O.

Abstract: A method-of producing a printed wiring board comprises: forming a via-hole for interlayer connection in a laminate in which a copper foil for laser processing comprises a copper foil and an easily soluble laser absorption layer provided on a surface of the copper foil which has a higher etching rate to a copper etchant than the copper foil and absorbs an infrared laser beam and another conductor layer is laminated through an insulating layer, directly irradiating the infrared laser beam on the easily soluble laser absorption layer; and removing the easily soluble laser absorption layer from the surface of the copper foil in a desmear step of removing a smear in a via-hole and/or a microetching step as a pretreatment of an electroless plating step is adopted.

Abstract: An object of the present invention is to provide a method of producing a printed wiring board which reduces production steps, is excellent in infrared laser processability, and is suitable for formation of an excellent wiring pattern; and to provide a copper foil for laser processing and a copper-clad laminate.

Abstract: A resin-coated copper foil for use in a multilayer printed wiring board, characterized by having on one surface thereof a resin composition comprising, based on the total amount of the resin components, 50 to 90% by weight of epoxy resins, 5 to 20% by weight of a polyvinyl acetal resin, and 0.1 to 20% by weight of an urethane resin, with the proviso that 0.5 to 40% by weight of the epoxy resins is a rubber-modified epoxy resin; and a multilayer printed wiring board using the resin-coated copper foil therein.

Abstract: A multilayer printed wiring board wherein an inner-layer copper circuit is provided on one or both of the surfaces of an inner-layer substrate, and subsequent copper circuit is cumulatively provided through an insulating layer on the outside of the inner-layer copper circuit, characterized in that the inner-layer copper circuit has a cuprous oxide film formed on the surface thereof the insulating layer which remarkably facilitate the interlayer adhesion between the inner-layer copper circuit. This multilayer printed wiring board has high interlayer adhesiveness and moistureproofness without causing any haloing phenomena when soaked with an acidic solution.