Method for activating a surface of a non-conductive or carbon-fibres containing substrate for metallization, the method including: (a) providing said substrate, (b) providing an aqueous, palladium-free activation composition comprising (i) a first species of dissolved transition metal ions and additionally metal particles thereof, (ii) at least one complexing agent, (iii) permanently or temporarily at least one reducing agent, (iv) optionally one or more second species of dissolved metal ions different from the first species, (c) contacting the substrate with said activation composition such that a transition metal or a transition metal alloy is deposited on the surface of said substrate and an activated surface for metallization is obtained.

A sensitizing solution, especially a sensitizing solution for sensitizing surfaces, containing a solution of tin(II) chloride SnCl.sub.2 and distilled water, especially for sensitizing non-conductive surfaces, which further contains glycerine. A method of preparation of the sensitizing solution, especially the method of preparation of the sensitizing solution, according to which the solution of tin(II) chloride SnCl.sub.2 and distilled water is mixed with a reducing agent, which is glycerine.

Provided is a method for manufacturing a circuit board including: (a) preparing a mixture of a metal powder, an anti-sintering agent, and an activator; (b) immersing a dielectric substrate in the mixture; (c) forming a metal-containing layer on the surface of the dielectric substrate by heating the mixture under an inert atmosphere or under a reducing atmosphere; (d) forming a first metal layer on the metal-containing layer by electroless plating and forming a second metal layer thereon by electroplating; and (e) forming a metal pattern on the dielectric substrate, wherein the first metal layer includes Cu, Ni, Co, Au, Pd, or an alloy thereof, the second metal layer includes Cu, Ni, Fe, Co, Cr, Zn, Au, Ag, Pt, Pd, Rh, or an alloy thereof, and the method further includes performing heat treatment at least once after step (c).

A method for manufacturing a surge absorbing device is provided. The method includes providing an elongate ceramic tube having a hollow space defined therein and having open and opposite first and second end; forming a first plating layer and a second plating layer on the first end and the second end, respectively; placing a surge absorbing element within the hollow space within the ceramic tube; disposing first and second brazing rings on the first plating layer and the second plating layer, respectively; disposing first and second sealing electrodes on the first and second brazing rings respectively; and melting the first and second brazing rings in an inert gas atmosphere to attach the first and second sealing electrodes onto the first plating layer and the second plating layer, respectively.

There is provided a hyper-branched polymer represented by the following formula (1) and having a weight-average molecular weight in a range of 1,000 to 1,000,000. In the formula (1), A.sup.1 is a group containing an aromatic ring, A.sup.2 is a group containing an amide group, A.sup.3 is a group containing sulfur, R.sup.0 is hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms, ml is in a range of 0.5 to 11, and n1 is in a range of 5 to 100. ##STR00001##

There is provided a hyper-branched polymer represented by the following formula (1) and having a weight-average molecular weight in a range of 1,000 to 1,000,000. In the formula (1), A.sup.1 is a group containing an aromatic ring, A.sup.2 is a group containing an amide group, A.sup.3 is a group containing sulfur, R.sup.0 is hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms, ml is in a range of 0.5 to 11, and n1 is in a range of 5 to 100. ##STR00001##

A substrate W having a non-plateable material portion 31 and a plateable material portion 32 formed on a surface thereof is prepared, and then, a catalyst is selectively imparted to the plateable material portion 32 by performing a catalyst imparting processing on the substrate W. Thereafter, a plating layer 35 is selectively formed on the plateable material portion 32 by supplying a plating liquid M1 onto the substrate W. The plating liquid M1 contains an inhibitor which suppresses the plating layer 35 from being precipitated on the non-plateable material portion 31.

A substrate W having a non-plateable material portion 31 and a plateable material portion 32 formed on a surface thereof is prepared, and then, a catalyst is selectively imparted to the plateable material portion 32 by performing a catalyst imparting processing on the substrate W. Thereafter, a plating layer 35 is selectively formed on the plateable material portion 32 by supplying a plating liquid M1 onto the substrate W. The plating liquid M1 contains an inhibitor which suppresses the plating layer 35 from being precipitated on the non-plateable material portion 31.

A method for manufacturing a package substrate including an insulating layer and a wiring conductor, including: forming, on one or both sides of a core resin layer, a substrate including a peelable first metal layer that has a thickness of 1-70 μm, a first insulating resin layer, and a second metal layer; forming a non-through hole reaching a surface of the first metal layer, performing electrolytic and/or electroless copper plating on its inner wall, and connecting the second and first metal layers; arranging a second insulating resin layer and a third metal layer and heating and pressurizing the first substrate to form a substrate; forming a non-through hole reaching a surface of the second metal layer, performing electrolytic and/or electroless copper plating on its inner wall, and connecting the second and third metal layers; peeling a third substrate; and patterning the first and third metal layers to form the wiring conductor.

An aluminum alloy substrate for a magnetic disk including an aluminum alloy containing 0.1 to 3.0 mass % of Fe, 0.005 to 1.000 mass % of Cu, and 0.005 to 1.000 mass % of Zn, with a balance of Al and inevitable impurities, wherein in an outer peripheral surface thereof, the number of holes having maximum diameters of 10 μm or more is 200/mm.sup.2 or less, an aluminum alloy base disk for a magnetic disk and a magnetic disk, using the aluminum alloy substrate, and methods for manufacturing these.