Abstract: A flexible printed wiring board according to an aspect of the present disclosure is a flexible printed wiring board including a base film and a plurality of wiring lines disposed on a front surface of the base film. Each of the wiring lines has a front end surface extending in a longitudinal direction of the wiring line and two side surfaces extending in the longitudinal direction, and the side surfaces have an arithmetical mean roughness Ra of 0.05 ?m to 2.0 ?m. The wiring lines have an average height of 40 ?m to 120 ?m. The wiring lines have an average spacing of 1 ?m to 30 ?m.

Abstract: A flexible printed wiring board according to an aspect includes a base film, a conductive pattern disposed on one surface of the base film, and an extra length absorbing portion protruding from the base film and disposed in a direction of a plane, the extra length absorbing portion including a pattern connected portion connected to the conductive pattern, a coupling portion having a first linear wiring portion, a first arcuate wiring portion, and a second linear wiring portion coupled in this order continuously from the pattern connected portion, and a connecting terminal connected to the coupling portion, the pattern connected portion and the connecting terminal being opposite to each other in a direction in which the extra length absorbing portion protrudes.

Abstract: A coil device has a first surface and a second surface as end surfaces of the coil device in a thickness direction. The coil device includes at least one printed wiring board, a first protective layer, and an external connection terminal. Each of the at least one printed wiring board has a first base film including a first main surface and a second main surface as a surface opposite to the first main surface, a first coil wire spirally formed on the first main surface, and a second coil wire spirally formed on the second main surface. The first protective layer covers the first main surface of one of the at least one printed wiring board disposed closest to the first surface. The external connection terminal is formed on the first protective layer, and is electrically connected to the first coil wire.

Abstract: A printed wiring board includes: a base material having a main surface; a conductive pattern that is disposed on the main surface; and a plating layer. A through hole is formed in the base material. The through hole extends through the base material in a thickness direction. A thickness of the base material is 0.5 mm or more. The plating layer is disposed on at least an inner wall surface of the through hole and electrically connected to a portion of the conductive pattern around the through hole. A thickness of the plating layer on the inner wall surface of the through hole is greater than a thickness of the conductive pattern and 10 ?m or more.

Abstract: The printed wiring board substrate includes an insulating layer, a first copper foil, and a second copper foil. The insulating layer has a first main surface and a second main surface opposite to the first main surface. The insulating layer includes a plurality of polyimide layers and a plurality of fluororesin layers. The total number of the plurality of polyimide layers and the plurality of fluororesin layers is 5 or more. Each of the plurality of polyimide layers and each of the plurality of fluororesin layers are alternately stacked along a thickness direction of the insulating layer. One of the plurality of fluororesin layers constitutes a first outermost layer which is an outermost layer on the side of the first main surface. Another one of the plurality of fluororesin layers constitutes a second outermost layer which is an outermost layer on the side of the second main surface.

Abstract: A printed wiring board includes: a base film having a first main surface and a second main surface; a first wire disposed on the first main surface; and a second wire disposed on the second main surface. The base film has a first portion and a second portion. The first portion and the second portion are arranged along a first direction, the first direction being a longitudinal direction of the base film in a plan view. A first boundary is along a second direction orthogonal to the first direction in a plan view, the first boundary being a boundary between the first portion and the second portion. The first wire has a first coil portion located in the first portion and wound spirally in a plan view, and a second coil portion located in the second portion and wound spirally in a plan view.

Abstract: A printed wiring board includes: a first conductive pattern; a dielectric layer that is disposed to cover the first conductive pattern; a second conductive pattern that is disposed on the dielectric layer; and a plating layer. A thickness of the dielectric layer is 50 ?m or more and 500 ?m or less. A hole from which the first conductive pattern is exposed is formed in the dielectric layer. An aspect ratio of the hole is 0.5 or more and 2.0 or less. The plating layer is disposed on at least an inner wall surface of the hole and the first conductive pattern exposed from the hole, and electrically connected to the second conductive pattern. A thickness of the plating layer disposed on the first conductive pattern exposed from the hole is greater than a thickness of the second conductive pattern.

Abstract: The coil device includes a plurality of printed wiring boards and an adhesive layer. The plurality of printed wiring boards are stacked in a thickness direction of the coil device. Each of the plurality of printed wiring boards includes a base film having a first main surface and a second main surface, and a coil wire formed in a spiral shape on at least one of the first main surface and the second main surface. The adhesive layer is disposed between the plurality of printed wiring boards adjacent to each other in the thickness direction of the coil device. The coil device has a portion that satisfies expression (1). 0.35 ? R ? 1 × R ? 2 ? 0.

Abstract: A printed wiring board includes: a dielectric layer having a main surface; and a conductive pattern. The conductive pattern includes a metal layer that is disposed on the main surface, an electroless plating layer that is disposed on the metal layer, and an electrolytic plating layer that is disposed on the electroless plating layer. An average thickness of the metal layer is 2.1 ?m or more and 9.0 ?m or less. Maximum height roughness of a surface of the metal layer opposed to the main surface is 5.0 ?m or less.

Abstract: A printed wiring board includes: a board having a through-hole; a land portion that is disposed on an inner circumferential surface of the through-hole and on a surface of the board at a circumferential edge of the through-hole, and that has a through-hole conductor portion; and a wire that is disposed on the surface of the board and that has one longitudinal end portion electrically connected to the land portion, a maximum length of a connection portion between the wire and the land portion being greater than or equal to a sum of a maximum diameter of the through-hole and a minimum line width of the wire.

Abstract: A method for manufacturing a dielectric sheet, includes the steps of extrusion molding a mixture including powder polytetrafluoroethylene and spherical silica at a temperature lower than or equal to a melting point of the polytetrafluoroethylene, and calendering a sheet body obtained by the extrusion molding. A mass ratio of the silica with respect to the polytetrafluoroethylene is 1.3 or greater. An average particle diameter of the silica is 0.1 ?m or greater but 3.0 ?m or less. A reduction ratio of the extrusion molding is 8 or less.

Abstract: A printed wiring board includes: a first insulating layer having a first main surface and a second main surface opposite to the first main surface; a first wire pattern, a second wire pattern, and a first ground pattern that are disposed on the second main surface and extend along a first direction in a plan view; a second ground pattern disposed on the first main surface; an adhesive layer disposed on the second main surface so as to cover the first wire pattern, the second wire pattern, and the first ground pattern; a second insulating layer disposed on the adhesive layer and having a third main surface facing the adhesive layer and a fourth main surface opposite to the third main surface; a third ground pattern disposed on the fourth main surface; and a first conductor layer and a second conductor layer.

Abstract: A substrate for a printed wiring board according to the present disclosure includes: a base material layer containing a thermoplastic resin; a metal nanoparticle layer, and a plating layer. The base material layer, the metal nanoparticle layer, and the plating layer are stacked in this order, and some of metal nanoparticles in the metal nanoparticle layer are embedded in the base material layer.

Abstract: A printed wiring board includes: a first insulating layer having a first main surface and a second main surface opposite to the first main surface; a first wire pattern, a second wire pattern and a first ground pattern disposed on the second main surface and extending along a first direction in a plan view; a second ground pattern disposed on the first main surface; an adhesive layer disposed on the second main surface so as to cover the first wire pattern, the second wire pattern and the first ground pattern; a second insulating layer disposed on the adhesive layer and having a third main surface facing the adhesive layer side and a fourth main surface opposite to the third main surface; a third ground pattern disposed on the fourth main surface; and a first conductor layer.

Abstract: The printed wiring board according to an embodiment of the present disclosure comprises: a substrate; a first wiring layer having a first wiring that is disposed directly or indirectly on the substrate; and a second wiring layer having a second wiring that is disposed directly or indirectly on the substrate. The average wire width of the first wiring is 40 ?m or less, and the average wire width of the second wiring is 50 ?m or more.

Abstract: A flexible printed circuit board includes a base film having an insulating property and a plurality of interconnects laminated to at least one surface side of the base film. The plurality of interconnects includes a first interconnect and a second interconnect in a same plane. An average thickness of the second interconnect being greater than an average thickness of the first interconnect. A ratio of the average thickness of the second interconnect to the average thickness of the first interconnect is greater than or equal to 1.5 and less than or equal to 50. The first interconnect includes a first conductive underlayer and a first plating layer, and the second interconnect includes a second conductive underlayer, a second plating layer, and a third plating layer.

Abstract: A printed wiring board includes a base layer having insulating properties, a first conductive layer directly or indirectly stacked on the base layer front surface, and including a copper foil, a second conductive layer directly or indirectly stacked on the base layer back surface, and including a copper foil, a stacked body for a via hole, the stacked body being stacked on an inner periphery and a bottom of a connection hole that extends through the first conductive layer and the base layer in a thickness direction, and being configured to electrically connect the first conductive layer and the second conductive layer to each other, and having an electroless copper plating layer. Each copper foil contains a copper crystal grain oriented in a plane orientation, and an average crystal grain size of copper of each copper foil is 10 ?m or greater, the electroless copper plating layer includes palladium.

Abstract: A dielectric sheet includes a polytetrafluoroethylene and spherical inorganic fillers, wherein a mass ratio of the inorganic fillers to the polytetrafluoroethylene is 1.3 or more, the inorganic fillers have an average particle diameter of 0.3 ?m to 4.0 ?m, and the inorganic fillers include a silica filler. Part of the polytetrafluoroethylene is present in the form of a plurality of fibrous bodies, and in a SEM image of a surface of the dielectric sheet after a 180-degree peel test, at least part of fibrous bodies among the plurality of fibrous bodies has areas with a thickness of 0.1 ?m to 3.0 ?m and a length of 50 ?m to 5000 ?m, and an average space between the areas of the at least part of fibrous bodies is 10 ?m or less.

Abstract: A flexible printed circuit board includes an electrically conductive line, and a land connected to the electrically conductive line and to be connected to a terminal, the land including soldering portions that have metal surfaces and to which the terminal is to be soldered. The terminal includes an overlapping section that overlaps the flexible printed circuit board and a protruding section that protrudes outward from the flexible printed circuit board and is soldered to a connecting member that connects electrode portions of power storage elements.

Abstract: A printed circuit board includes a base film having a main surface, and an electrically conductive pattern disposed on the main surface. A normal line of the main surface is along a first direction. The electrically conductive pattern includes a plurality of wiring portions disposed side by side along a second direction to be spaced apart from each other, the second direction being orthogonal to the first direction. The plurality of wiring portions include a first wiring portion and a second wiring portion that are each present at a corresponding one of both ends in the second direction and a plurality of third wiring portions that are present between the first wiring portion and the second wiring portion in the second direction.