The present invention relates to a resin composition containing a compound having a maleimido group, a divalent group having at least two imido bonds and a saturated or unsaturated divalent hydrocarbon group.

A wiring board includes core substrate, a first build-up layer on first surface of the substrate and including conductive and insulating resin layers, and a second build-up layer on second surface of the substrate and including conductive and insulating resin layers. The first build-up is formed such that each conductive layer includes a metal foil layer and a plating layer on the foil layer and the foil layer of a conductive layer on an outermost resin layer has thickness greater than thickness of the foil layer of a conductive layer on a non-outermost resin layer, and the second build-up is formed such that each conductive layer includes a metal foil layer and a plating layer on the foil layer and the foil layer of a conductive layer on an outermost resin layer has thickness greater than thickness of the foil layer of a conductive layer on a non-outermost resin layer.

A multi-layered board includes: a middle conductive layer; a first dielectric layer that is disposed directly on a first surface of the middle conductive layer; a second dielectric layer that is disposed directly on a second surface of the middle conductive layer; a first outer surface conductive layer that is disposed directly on an outer side of the first dielectric layer; and a second outer surface conductive layer that is disposed directly on an outer side of the second dielectric layer. The first outer surface conductive layer serves as a first outer surface of the multi-layered board, and the second outer surface conductive layer serves as a second outer surface of the multi-layered board. The middle conductive layer is solidly formed over an entire planar direction of the multi-layered board. The first dielectric layer and the second dielectric layer each independently have a thickness variation of 15% or less.

Methods for forming electrical circuitries on three-dimensional (3D) structures and devices made using the methods. A method includes forming selectively shaped 3D structures using additive manufacturing. The method includes forming undercuts on upper-level pedestals of the 3D structures that effectively act as overhanging deposition masks for selectively preventing deposition of a selected material on a corresponding portions of lower levels. The method includes simultaneously forming and electrically isolating materials directionally deposited on the 3D structure.

A board-to-board connecting structure which adds no significant thickness to a single printed circuit board includes a first circuit board and a second circuit board. The first circuit board includes first circuit substrate, adhesive layer, and second circuit substrate. The first circuit substrate includes first base layer, first inner wiring layer with first pad, and first outer wiring layer defining a receiving space. The second circuit substrate includes insulating layer and two second outer wiring layers. A conductive via in the second circuit substrate connects the two second outer wiring layers. The second circuit board includes second base layer and also two third outer wiring layers each with a second pad. The second circuit board is laterally disposed in the receiving space and one second pad connects to the conductive via and the other to the first pad.

A flexible printed circuit and manufacturing method thereof, and a displaying device. A wiring layer is arranged on a flexible substrate, a reinforcing layer is arranged on a side of the flexible substrate away from the wiring layer, the wiring layer comprises a plurality of signal wirings arranged along a first wiring area, a second wiring area, a third wiring area and a fourth wiring area, and the reinforcing layer comprises a first reinforcing structure located in the second wiring area and a second reinforcing structure located in the fourth wiring area. The impact strength of the flexible printed circuit is increased by arranging the first reinforcing structure in the second wiring area of the flexible substrate and arranging the second reinforcing structure in the fourth wiring area of the flexible substrate.

A die can be applied to a front conductive layer. Openings can be formed in the conductive layer over contact points on the die. The openings can be filled with a conductive material to electrically couple the conductive layer to the contact points on the die. The front conductive layer can be etched to form a first conductive pattern. Conductive standoffs can be formed on portions of the front conductive layer. An additional front conductive layer can be laminated onto the front side. Openings can be formed in the additional front conductive layer over the standoffs. The openings can be filled with a conductive material to electrically couple the additional conductive layer to the underlying standoffs. The additional conductive layer can be etched to form a second conductive pattern.

A printed wiring board includes a first insulator, a second insulator, a first conductor, and a second conductor. The first conductor is between the first insulator and the second insulator. The first conductor contains a first conductive material. The second conductor includes a first portion. The first portion is between the first insulator and the first conductor. The first portion is in contact with the first conductor and extends along the first conductor. The second conductor contains a second conductive material. The second conductive material is lower in electrical resistivity than the first conductive material. The second insulator is closer to an outside of the printed wiring board than the first insulator is in a thickness direction of the printed wiring board.

A method of manufacturing a base plate includes the following steps: providing a first substrate, the first substrate including a first base layer, a first copper coating and a second copper coating covered on two sides of the first base layer; opening at least one first hole on the first substrate, the first hole penetrating the first base layer and the first copper; forming a first electroplated coating on the first copper coating, the first copper coating filling the first hole to form a first connecting portion; opening at least one second hole on the first connecting portion and the first electroplated coating to form a plurality of second connecting pins.

A printed wiring board includes a first insulator, a second insulator, a first conductor, and a second conductor. The first conductor is between the first insulator and the second insulator. The first conductor contains a first conductive material. The second conductor includes a first portion. The first portion is between the first insulator and the first conductor. The first portion is in contact with the first conductor and extends along the first conductor. The second conductor contains a second conductive material. The second conductive material is lower in electrical resistivity than the first conductive material. The second insulator is closer to an outside of the printed wiring board than the first insulator is in a thickness direction of the printed wiring board.