A substrate having a recess, a diffusion barrier layer defining the recess, and a wiring exposed at a bottom of the recess is prepared. A metal ion, having a concentration not causing precipitation of a metal even when an electroless plating liquid comes into contact therewith, is attached to the diffusion barrier layer. The metal is precipitated in the recess by supplying the electroless plating liquid into the recess in a state that the metal ion is attached to the diffusion barrier layer.

In one example, an electronic device housing may include a substrate, a micro-arc oxidation layer formed on a surface of the substrate, and an electroless plating layer formed on the micro-arc oxidation layer. Example electroless plating layer may be one of an electroless tin plating layer and an electroless silver plating layer. Further, the electronic device housing may include an electrophoretic deposition layer formed on the electroless plating layer.

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.

According to one embodiment, an etching method includes etching a surface made of a semiconductor and having a catalyst layer formed on the surface, by an etching agent in contact with the surface. The catalyst layer contains noble metal. The etching agent contains an oxidizer, a corrosive agent, and a N-containing polymer agent.

Cleaning solution for cleaning and/or wetting metal surfaces, comprising at least one acid, a first surfactant, which is an alkyl-poly(ethyleneglycol-co-propyleneglycol)-ether having a cloud point of ≤25° C., a second surfactant, which is selected from the group consisting of i) an alkyl-poly(ethyleneglycol-co-propyleneglycol)-ether having a cloud point of ≥30° C., ii) an alkyl-polyethyleneglycol-ether having a cloud point of ≥45° C.
wherein the cloud points are determined according to European Standard EN 1890:2006, item 8.2 of German Version, with the modification that 10 wt % H.sub.2SO.sub.4 is used as solvent and that the concentration of the surfactant is 1000 mg/L.

The amount of a processing solution used is reduced, and the quality of an electroless plated fiber material is improved. The present invention relates to a manufacturing method for an electroless plated fiber material A4. The manufacturing method includes a step S5 of electrostatically spraying a solution B containing a catalyst precursor in a state of being electrically charged to a positive potential onto a fiber material A2 while grounding the fiber material A2 and moistening the fiber material A2, and electrostatically spraying a solution C containing a reducing agent in a state of being electrically charged to a positive potential onto the fiber material A2, and a step S7 of electrostatically spraying each of a solution D containing metal ions and a solution E containing a reducing agent each in a state of being electrically charged to a positive potential onto the fiber material A3 such that the solution D containing metal ions and the solution E containing the reducing agent react with each other in the same electric field on the fiber material A3 while grounding the fiber material A3 to which a catalyst is given and moistening the fiber material A3. The present invention relates to the electroless plated fiber material A4 manufactured by the manufacturing method. The present invention relates to a manufacturing system of the electroless plated fiber material A4.

The amount of a processing solution used is reduced, and the quality of an electroless plated fiber material is improved. The present invention relates to a manufacturing method for an electroless plated fiber material A4. The manufacturing method includes a step S5 of electrostatically spraying a solution B containing a catalyst precursor in a state of being electrically charged to a positive potential onto a fiber material A2 while grounding the fiber material A2 and moistening the fiber material A2, and electrostatically spraying a solution C containing a reducing agent in a state of being electrically charged to a positive potential onto the fiber material A2, and a step S7 of electrostatically spraying each of a solution D containing metal ions and a solution E containing a reducing agent each in a state of being electrically charged to a positive potential onto the fiber material A3 such that the solution D containing metal ions and the solution E containing the reducing agent react with each other in the same electric field on the fiber material A3 while grounding the fiber material A3 to which a catalyst is given and moistening the fiber material A3. The present invention relates to the electroless plated fiber material A4 manufactured by the manufacturing method. The present invention relates to a manufacturing system of the electroless plated fiber material A4.

A method of making a composite material includes disposing a carbon-based particulate material, such as graphene or carbon nanotubes, in an activation solution and activating surfaces of the carbon-based particulate material using the activation solution. Once the surfaces of the carbon-based particulate material have been activated, a metallic coating is applied to the activated surfaces to form a composite material. The composite material is then recovered as a particulate material formed having carbon-based particulate material with a metallic coating that is suitable for fusing together for forming electrical conductors, such as with an additive manufacturing technique.

Compositions for electroless plating baths and their use are disclosed, and more particularly different solutions each usable to both makeup an original bath and to replenishment of the original bath.

The present invention aims to provide a metal displacement solution that can provide good adhesion to a plating film (metal film), and a method for surface treatment of aluminum or an aluminum alloy using the metal displacement solution. Included is a metal displacement solution which contains a zinc compound, a nickel compound, a germanium compound, and a fluorine compound.