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 μm or greater but 3.0 μm or less. A reduction ratio of the extrusion molding is 8 or less.

A circuit board and an electronic device having the circuit board that includes a ceramic sintered body, a through conductor and a metal wiring layer. The ceramic sintered body includes a through hole penetrating from a first main surface to a second main surface thereof. The through conductor is in the through hole and has first and second ends. The metal wiring layer covering the first end and electrically connected to the through conductor. The through conductor includes: a first portion having a hollow cylinder shape, in contact with an inner wall of the through hole and extending from the first end to the second end; and a second portion having a columnar shape and disposed inside the first portion. The second portion has an average grain size of the metal larger than that in the first portion.

Pastes are disclosed that are configured to coat a passage of a substrate. When the paste is sintered, the paste becomes electrically conductive so as to transmit electrical signals from a first end of the passage to a second end of the passage that is opposite the first end of the passage. The metallized paste contains a lead-free glass frit, and has a coefficient of thermal expansion sufficiently matched to the substrate so as to avoid cracking of the sintered paste, the substrate, or both, during sintering.

A stretchable mounting board that includes a mounting electrode section electrically connected to stretchable wiring, and solder electrically connected to the mounting electrode section. The mounting electrode section has a first electrode layer on a side thereof facing the stretchable wiring and which includes bismuth and tin, and a second electrode layer on a side thereof facing the solder and which includes bismuth and tin. A concentration of the bismuth in the first electrode layer is lower than a concentration of the bismuth in the second electrode layer, and the concentration of the bismuth in the second electrode layer is constant along a thickness direction thereof.

In an embodiment, a thermoplastic composite comprises a thermoplastic polymer; and a dielectric filler having a multimodal particle size distribution; wherein a peak of a first mode of the multimodal particle size distribution is at least seven times that of a peak of a second mode of the multimodal particle size distribution; and a flow modifier.

The present disclosure relates to a dielectric substrate that may include a first fluoropolymer based adhesive layer, a polyimide layer overlying the fluoropolymer based adhesive layer, and a first filled polymer layer overlying the polyimide layer. The first filled polymer layer may include a resin matrix component, and a first ceramic filler component. The first ceramic filler component may include a first filler material. The first filler material may further have a mean particle size of at not greater than about 10 microns.

The present disclosure relates to a dielectric substrate that may include a polymer based core film, and a fluoropolymer based adhesive layer. The polymer based core film may include a resin matrix component, and a ceramic filler component. The ceramic filler component may include a first filler material. The particle size distribution of the first filler material may have a D.sub.10 of at least about 1.0 microns and not greater than about 1.7, a D.sub.50 of at least about 1.0 microns and not greater than about 3.5 microns, and a D.sub.90 of at least about 2.7 microns and not greater than about 6 microns.

A printed circuit board includes an insulating layer; a metal pad disposed on one side of the insulating layer; a via hole penetrating through the insulating layer to expose at least a portion of the metal pad; and a via filling at least a portion of the via hole, wherein the via comprises a first metal layer and a second metal layer disposed on the first metal layer, and an average size of grains in the first metal layer and an average size of grains in the second metal layer are different from each other.

According to embodiments of the present invention, an ink composition is provided. The ink composition includes a plurality of nanostructures distributed in at least two cross-sectional dimension ranges, wherein each nanostructure of the plurality of nanostructures is free of a cross-sectional dimension of more than 200 nm. According to further embodiments of the present invention, a method for forming a conductive member and a conductive device are also provided.

A resin composition for a circuit board, containing a melt-fabricable fluororesin and a particulate boron nitride. The particulate boron nitride has a ratio (b)/(a) of 1.0 or higher, wherein (a) represents a proportion of particles having a particle size of 14.6 to 20.6 μm and (b) represents a proportion of particles having a particle size of 24.6 to 29.4 μm. Also disclosed is a molded article for a circuit board obtained from the resin composition, a laminate for a circuit board including a metal layer (A1) and a layer (B) obtained from the resin composition, and a circuit board including a metal layer (A2) and a layer (B) obtained from the resin composition.