Disclosed is a fabrication method for electronic products, comprising planarization coating of a flexible substrate using a radiation curable composition.

A coating liquid for forming a conductive layer according to an embodiment of the present invention contains fine metal particles, a dispersion medium, and a dispersant. The coating liquid has a pH of 4 or more and 8 or less, an electrical conductivity of 100 S/cm or more and 800 S/cm or less, and a content of the fine metal particles of 20% by mass or more and 80% by mass or less. A method for manufacturing a conductive layer according to another embodiment of the present invention is a method for manufacturing a conductive layer using a coating liquid for forming a conductive layer, the coating liquid containing fine metal particles, a dispersion medium, and a dispersant. The method includes an application step of applying the coating liquid for forming a conductive layer, and a heating step of heating the coating liquid for forming a conductive layer after application. At the time of the application, the coating liquid for forming a conductive layer has a pH of 4 or more and 8 or less, an electrical conductivity of 100 S/cm or more and 800 S/cm or less, and a content of the fine metal particles of 20% by mass or more and 80% by mass or less.

Provided are: a curable composition that shows good adhesion on a printed wiring board, particularly a flexible substrate or the like, and has a high hardness; a resist coating film of the curable composition; and a printed wiring board having a resist pattern of the resist coating film. The curable composition comprises: (A) a photobase generator; (B-1) an epoxy group-containing (meth)acrylate compound or (B-2) a carboxyl group-containing (meth)acrylate compound; (C) a photopolymerization initiator; and (D-1) a thermosetting component (excluding the (B-1) epoxy group-containing (meth)acrylate compound) or (D-2) a thermosetting component (excluding the (B-2) carboxyl group-containing (meth)acrylate compound).

A method for manufacturing traces of a printed circuit board (PCB) comprises an application of the periodic pulse reverse (PPR) pattern plating process. In the first stage, walls and bottoms in drilled holes of the PCB are modified with reduced graphene oxide (rGO) so that the vias can be formed by filling with copper and a very thin copper layer can be formed on the substrate through the electroplating process. In the second stage, a pattern of very fine traces with width/space less than 30/30 m is formed on the thin copper layer and then the traces are formed through the PPR pattern plating process. After removing unwanted copper layer, the traces with even thicknesses and square profiles are achieved and thus conform to requirements of the high density interconnection (HDI) technology.

A flexible printed circuit board includes a thin film electrical insulation substrate made of heat-curable resin having heat resistance and electrical insulation properties, an electrically conductive pattern composed of an electric conductor formed on the thin film electrical insulation substrate in a prescribed shape, and a thin film cover lay made of heat-curable resin placed and cured on the thin film electrical insulation substrate to cover the electrically conductive pattern.

Systems and methods of the present disclosure are directed to an electronic substrate. The electronic substrate includes a base layer, first feature(s) formed from a first metal layer and a second metal layer, and second feature(s) formed from the first metal layer. The electronic substrate includes a polymerized photodielectric layer over the first feature(s) and the second feature(s). The polymerized photodielectric layer exposes a portion of the second metal layer of the first feature(s), and at least a portion of the first metal layer of the second feature(s).

A resin composition having lower dielectric constant D.sub.k, lower dielectric loss D.sub.f, lower water absorption, higher surface impedance, and higher glass transition temperature includes resins. The resins have a chemical structure selected from a group consisting of

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or any combination thereof.

A transparent conductor is provided, including a visible light transparent substrate and metal traces disposed on the substrate, and a layer of a second metal deposited on at least a portion of the metal traces. The transparent conductor further includes a layer of a second metal, which conforms to the surface structure of the metal traces on which it is deposited. Optionally, the transparent conductor also includes a coating layer disposed on a portion of the metal traces and the substrate surface. The coating layer includes a polymer prepared from a polymerizable composition containing at least one ionic liquid monomer. A method of forming a transparent conductor is also provided, including obtaining a visible light transparent substrate having metal traces disposed on the substrate and applying a coating composition on a portion of the metal traces and substrate. The coating composition contains at least one noble metal salt and at least one polymerizable ionic liquid monomer.

Disclosed herein is a printed circuit board having a structure for preventing coating liquid overflow. In the printed circuit board on which an electronic component is mounted and in which a connection hole for joining the electronic component and another component to each other is formed, a land region to which lead may be applied is formed adjacent to the connection hole.

To prevent degradation of electrical characteristics caused by a resin filled between electrodes in an ultraviolet light-emitting operation, the present invention provides a base 10 that comprises an insulating base material 11 and two or more metal films 12 and 13 that are formed on one side of the insulating base material 11 and electrically separated from each other. The two or more metal films are formed to include an upper surface and a side wall surface that are covered by gold or a platinum group metal, to be capable of mounting thereon one or more nitride semiconductor light-emitting elements and the like, and to have, as a whole, a predetermined planar view shape including two or more electrode pads. On the one side of the base material 11, along a boundary line between an exposed surface of the base material 11 that is not covered by the metal film 12, 13 and a side wall surface of the metal film 12, 13, at least a first part of the exposed surface of the base material 11 continuous with the boundary line that is sandwiched between two adjacent electrode pads and the side wall surfaces of the metal films 12 and 13 that oppose to each other with the first part interposed therebetween are covered by a fluororesin film 16, and a part of an upper surface of the metal film 12, 13 that composes at least the electrode pad is not covered by the fluororesin film 16.