A substrate for a printed circuit board according to an embodiment of the present invention includes a base film having insulating properties and a sintered layer formed of a plurality of metal particles, the sintered layer being stacked on at least one surface of the base film, in which a region of the sintered layer extending from an interface between the sintered layer and the base film to a position 500 nm or less from the interface has a porosity of 1% or more and 50% or less.

A circuit board element includes a glass substrate, a first dielectric layer, and a first patterned metal layer. The glass substrate has an edge. The first dielectric layer is disposed on the glass substrate and has a central region and an edge region. The edge region is in contact with the edge of the glass substrate, and the thickness of the central region is greater than the thickness of the edge region. The first patterned metal layer is disposed on the glass substrate and in the central region of the first dielectric layer.

A polyamic acid solution includes a dianhydride and a diamine. The dianhydride includes pyromellitic dianhydride, the diamine includes a benzimidazole, the molar ratio of dianhydride monomer to diamine monomer is in a range of from 0.85:1 to 0.99:1, and the polyamic acid solution has a solids content in a range of from 10 to 25 weight percent and a viscosity in a range of from 300 to 3000 poise.

A method for producing a wiring circuit board includes a first step, a second step, and a third step. In the first step, while a work film which is a long metal substrate having a first surface and a second surface opposite to the first surface is fed and wound by a roll-to-roll method, a composition containing a photosensitive resin is applied onto the first surface to form an insulating film, and a protective film is interposed between the second surface and the insulating film of the work film in being wound. In the second step, while the work film having undergone the first step is fed and wound by the roll-to-roll method, the protective film is peeled from the insulating film, and the insulating film is subjected to light exposure treatment to be formed with a latent image pattern. In a third step, the insulating film having undergone the second step is subjected to development treatment to be patterned.

A resin composition includes 100 parts by weight of a maleimide resin; 20 parts by weight to 60 parts by weight of a benzoxazine resin; 5 parts by weight to 40 parts by weight of an epoxy resin; 120 parts by weight to 240 parts by weight of silica including spherical silica having a sediment volume of less than or equal to 0.4 mL/g and a particle size distribution D50 of less than or equal to 1.0 μm; and 0.5 part by weight to 1.6 parts by weight of an imidazole compound having a long-chain alkyl group, wherein the imidazole compound having a long-chain alkyl group includes octylimidazole, undecylimidazole, heptadecylimidazole or a combination thereof. The resin composition may be used to make a prepreg, a resin film, a laminate or a printed circuit board, and at least one of the following improvements can be achieved, including glass transition temperature, ratio of thermal expansion, copper foil peeling strength, thermal resistance after moisture absorption, dissipation factor, amount of resin cluster and appearance of cooper-free circuit board.

A wiring board includes a wiring layer, an insulating layer, a plurality of opening portions, and a connection terminal. The insulating layer is laminated on the wiring layer and covers a wiring pattern. Each of the plurality of opening portions penetrates through the insulating layer to the wiring pattern. The connection terminal is formed on the respective opening portions and comes into contact with the upper surface of the wiring pattern. The wiring layer includes a first wiring pattern, and a second wiring pattern that is formed of a plurality of laminated metal layers and that is thicker than the first wiring pattern. An upper surface of a metal layer serving as an uppermost layer of the second wiring pattern is a contact surface with the connection terminal and has a same width as an upper surface of a metal layer serving as a layer other than the uppermost layer.

The embodiment of the disclosure provides a composite layer circuit element and a manufacturing method thereof. The manufacturing method of the composite layer circuit element includes the following. A carrier is provided. A first dielectric layer is formed on the carrier, and the first dielectric layer is patterned. The carrier on which the first dielectric layer is formed is disposed on a first curved-surface mold, and the first dielectric layer is cured. A second dielectric layer is formed on the first dielectric layer. The second dielectric layer is patterned. The carrier on which the first dielectric layer and the second dielectric layer are formed is disposed on a second curved-surface mold, and the second dielectric layer is cured. A thickness of a projection of the first curved-surface mold is smaller than a thickness of a projection of the second curved-surface mold.

A method for manufacturing a circuit board structure with a waveguide is provided. The method includes: providing a first substrate unit, a second substrate unit, a third substrate unit, and two adhesive layers, the first substrate unit including a first dielectric layer and a first conductive layer, the first conductive layer including a first shielding area and two first artificial magnetic conductor areas disposed on two sides of the first shielding area; the second substrate unit including a second dielectric layer and a second conductive layer, the second conductive layer including a second shielding area; the third substrate unit defining a first slot, and the adhesive layer defining a second slot; stacking the first substrate unit, one of the adhesive layers, the third substrate unit, another one of the adhesive layers, and the second substrate unit in that order; pressing the intermediate body.

A polyimide film is a reaction product of a diamine component and an acid dianhydride component. The diamine component contains p-phenylenediamine, a first aromatic diamine, and a second aromatic diamine. The first aromatic diamine and the second aromatic diamine are different from each other and represented by the following formula (1):

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In the diamine component, each of a molar fraction of the p-phenylenediamine, a molar fraction of the first aromatic diamine, and a molar fraction of the second aromatic diamine is 10% by mole or more and 70% by mole or less. The acid dianhydride component contains an acid dianhydride containing an aromatic ring.

In an x-ray source, an isolation circuit can isolate bias voltage at a cathode from a bias voltage at an alternating current source (AC source). The isolation circuit can transfer alternating current from the AC source to the cathode. The isolation circuit can be made repeatedly with minimal variation or failed parts, can be light, and can be small. The isolation circuit can include planar transformer(s). Each planar transformer can include a primary trace on a primary circuit board and a secondary trace on a secondary circuit board. The primary trace and the secondary trace can each include a spiral shape. The primary trace can be located in close proximity to the secondary trace such that alternating electrical current through the primary trace will induce alternating electrical current through the secondary trace.