The present invention provides a process for preparing a pre-treated low Dk-type glass fabric for constituting a circuit board, comprising pre-treating low Dk-type glass fabric with a pre-treating varnish having a Dk close to the Dk of the used low Dk-type glass fabric at different temperatures and having a small Df. The present invention further provides a bonding sheet and a circuit board prepared thereby. The circuit boards prepared by the preparation process of the present invention have a Dk having small differences in warp and weft directions, and can effectively solve the problem of signal propagation delay. The circuit boards have a small Df, so as to have a small signal loss. Meanwhile, the cured, partially-cured or uncured dry glue obtained after drying the solvent of the pre-treating varnish has similar dielectric properties at different temperatures to the used low Dk-type glass fabric, so that the circuit boards have a very small signal propagation delay at different temperatures.

A second main surface of the copper plate is opposite a first main surface of the copper plate, and is bonded to a silicon nitride ceramic substrate by the bonding layer. A first portion and a second portion of an end surface of the copper plate form an angle of 135° to 165° on an outside of the copper plate. An extended plane of the first portion and the second main surface form an angle of 110° to 145° a side where the second portion is located. A distance from the second main surface to an intersection of the first portion and the second portion in a direction of a thickness of the copper plate is 10 to 100 μm. The second main surface extends beyond the extended plane of the first portion by a distance of 10 μm or more.

A second main surface of the copper plate is opposite a first main surface of the copper plate, and is bonded to a silicon nitride ceramic substrate by the bonding layer. A first portion and a second portion of an end surface of the copper plate form an angle of 135° to 165° on an outside of the copper plate. An extended plane of the first portion and the second main surface form an angle of 110° to 145° a side where the second portion is located. A distance from the second main surface to an intersection of the first portion and the second portion in a direction of a thickness of the copper plate is 10 to 100 μm. The second main surface extends beyond the extended plane of the first portion by a distance of 10 μm or more.

The present disclosure provides a micro-rough electrolytic copper foil and a copper clad laminate. The electrolytic copper foil has a micro-rough surface formed with mountain-shaped structures and recessed structures. A multiplication value of an arithmetic mean height (Sa) and a vertex density (Spd) of the mountain-shaped structures measured according to ISO 25178 is between 150000 μm/mm.sup.2 and 400000 μm/mm.sup.2. An arithmetic mean undulation (Wa) of the mountain-shaped structures measured according to JIS B0601:2001 is between 0.06 μm and 1.5 μm. Therefore, the electrolytic copper foil with good binding strength and electrical properties can be obtained.

A copper-clad laminate including at least one of a copper layer having a roughened surface is disclosed. The copper-clad laminate is obtained by roughening at least one surface of a base copper layer so as to have a low profile comprising a copper layer having a thickness of from 5 μm to 70 μm and a resin layer on the copper layer, wherein a peeling strength between the copper layer and the resin layer is more than 0.6 N/mm when the thickness of the copper layer is more than 5 μm, wherein a ten-point mean roughness Sz of the roughened surface is lower than that of the base copper layer.

There is provided a laminate in which a decrease in the release function of a release layer can be suppressed even when the laminate is heat-treated under either temperature condition of low temperature and high temperature. This laminate includes a carrier; an adhesion layer on the carrier and containing a metal M.sup.1 having a negative standard electrode potential; a release-assisting layer on a surface of the adhesion layer opposite to the carrier and containing a metal M.sup.2 (M.sup.2 is a metal other than an alkali metal and an alkaline earth metal); a release layer on a surface of the release-assisting layer opposite to the adhesion layer; and a metal layer on a surface of the release layer opposite to the release-assisting layer, and T.sub.2/T.sub.1, a ratio of a thickness of the release-assisting layer, T.sub.2, to a thickness of the adhesion layer, T.sub.1, is more than 1 and 20 or less.

A surface treated copper foil 1 includes a copper foil 2, and a first surface treatment layer 3 formed on one surface of the copper foil 2. The first surface treatment layer 3 of the surface treated copper foil 1 has a root mean square gradient of roughness curve elements RΔq according to JIS B0601:2013 of 5 to 28°. A copper clad laminate 10 includes the surface treated copper foil 1 and an insulating substrate 11 adhered to the first surface treatment layer 3 of the surface treated copper foil 1.

A laminate comprising a substrate; and a plating-forming layer disposed on at least one surface of both surfaces of the substrate and containing a thermoplastic resin and a plating catalyst, wherein the plating-forming layer further satisfies conditions of the following (1) and/or (2),

(1) the plating-forming layer contains a dispersing agent for dispersing the plating catalyst
(2) an abundance of the plating catalyst on a surface side of the plating-forming layer is higher than an abundance of the plating catalyst on the substrate side of the plating-forming layer.

A method for manufacturing a wiring board capable of improving adhesion between an underlayer and a seed layer. An electrically conductive underlayer is disposed on the surface of an insulating substrate and a seed layer containing metal is disposed on the surface of the underlayer to prepare a substrate with seed-layer. A diffusion layer in which elements forming the underlayer and seed layer are mutually diffused is formed between the underlayer and the seed layer, by irradiating the seed layer with a laser beam. A metal layer is formed on the surface of the seed layer by disposing a solid electrolyte membrane between an anode and the seed layer as a cathode and applying voltage between the anode and the underlayer. An exposed portion without the seed layer of the underlayer is removed from the insulating substrate.

A wiring substrate includes a first insulating layer, a first conductor layer, a second insulating layer, a second conductor layer, a connection conductor penetrating through the second insulating layer and connecting the first and second conductor layers, and a coating film formed on a surface of the first conductor layer such that the coating film is adhering the first conductor layer and the second insulating layer. The first conductor layer includes a conductor pad and a wiring pattern such that the conductor pad is in contact with the connection conductor and the wiring pattern is covered by the coating film, the conductor pad of the first conductor layer has a surface facing the second insulating layer and having a first surface roughness higher than a surface roughness of a surface of the wiring pattern, and the coating film has opening such that the opening is exposing the conductor pad entirely.