Abstract: A substrate manufacturing method includes an inner layer circuit forming step for partially removing metal films from an insulating base material (2), on both surfaces of which the metal films are stuck, and forming an inner layer circuit (3); and an insulating layer forming step for applying first insulating resin (4) to each of both the surfaces of the insulating base material (2) with an inkjet system and forming an insulating layer (5). In the insulating layer forming step, a via hole (6) from which the inner layer circuit (3) is partially exposed is formed simultaneously with the application of the first insulating resin (4). Consequently, a step of separately forming a via hole with a laser or the like is unnecessary, expenses are relatively low, and it is possible to simplify a manufacturing process.

Abstract: A method of fabricating a heat dissipating board according to the present invention, includes: a substrate intermediate forming step of forming a substrate intermediate with an insulating layer made of an insulating resin material and a conducting layer made of a conductive material formed on the insulating layer; a through hole forming step of forming a through hole having an approximately cylindrical shape, the through hole penetrating through the substrate intermediate; an inserting step of inserting a heat conducting member to be disposed in the through hole, the heat conducting member being made of a metal and having an approximately cylindrical shape; and a plastically deforming step of plastically deforming the heat conducting member to be secured in the through hole. Prior to the inserting step, an annealing step of annealing the heat conducting member is performed.

Abstract: A method of fabricating a heat dissipating board according to the present invention, includes: a substrate intermediate forming step of forming a substrate intermediate with an insulating layer made of an insulating resin material and a conducting layer made of a conductive material formed on the insulating layer; a through hole forming step of forming a through hole having an approximately cylindrical shape, the through hole penetrating through the substrate intermediate; an inserting step of inserting a heat conducting member to be disposed in the through hole, the heat conducting member being made of a metal and having an approximately cylindrical shape; and a plastically deforming step of plastically deforming the heat conducting member to be secured in the through hole. Prior to the inserting step, an annealing step of annealing the heat conducting member is performed.

Abstract: A method of producing a printed circuit board includes: forming a metal layer on a support plate; forming a mask layer on the metal layer; forming a pattern plating having a stem as plating up to a level of the mask layer, and a cap as a portion of plating exceeding the mask layer and having an outgrowth lying over the surface of the mask layer; laminating an insulating base on a conductive circuit board constituted by the support plate, the metal layer and the pattern plating to form a circuit board intermediate in which the pattern plating is buried in the base; removing the support plate and the metal layer to form an exposed surface; and mechanically polishing the exposed surface until the stem of the pattern plating is removed, to increase the width of the conductive pattern on the exposed surface.

Abstract: A substrate manufacturing method includes an inner layer circuit forming step for partially removing metal films from an insulating base material (2), on both surfaces of which the metal films are stuck, and forming an inner layer circuit (3); and an insulating layer forming step for applying first insulating resin (4) to each of both the surfaces of the insulating base material (2) with an inkjet system and forming an insulating layer (5). In the insulating layer forming step, a via hole (6) from which the inner layer circuit (3) is partially exposed is formed simultaneously with the application of the first insulating resin (4). Consequently, a step of separately forming a via hole with a laser or the like is unnecessary, expenses are relatively low, and it is possible to simplify a manufacturing process.

Abstract: A method of producing a printed circuit board includes: forming a metal layer on a support plate; forming a mask layer on the metal layer; forming a pattern plating having a stem as plating up to a level of the mask layer, and a cap as a portion of plating exceeding the mask layer and having an outgrowth lying over the surface of the mask layer; laminating an insulating base on a conductive circuit board constituted by the support plate, the metal layer and the pattern plating to form a circuit board intermediate in which the pattern plating is buried in the base; removing the support plate and the metal layer to form an exposed surface; and mechanically polishing the exposed surface until the stem of the pattern plating is removed, to increase the width of the conductive pattern on the exposed surface.

Abstract: The present invention provides the miniaturization and weight reduction of the multi-layer circuit board and improvement in the processability thereof. The multi-layer circuit board comprises a substrate 10, on at least one surface of a substrate 10, a first electrical conductive circuit (metal plating film 30) disposed on the substrate 10, an resin layer 20 disposed on the first electrical conductive circuit and a second electrical conductive circuit (metal plating film 30) disposed on the resin layer. The resin layer 20 is composed of a resin compound including benzocyclobutene resin, particulate inorganic filler and ultraviolet absorbent.

Abstract: A magnetic erasing head in which a single rear core has a plurality of integrally formed legs. A front core is provided with a plurality of core pieces bonded to each other to form paired units, each unit having an erasing gap formed between adjacent core pieces a coil is adapted to surround one leg of the rear core and supplied with erasing current. The rear end surface of the core pieces of the front core are bonded to corresponding end surfaces of the legs of the rear core.