A steel sheet for can making and methods for manufacturing the same. The steel sheet includes, in order from a steel sheet side, an iron-nickel diffusion layer, a metallic chromium layer, and a chromium oxide layer. The iron-nickel diffusion layer has a nickel coating weight of 50 mg/m.sup.2 to 500 mg/m.sup.2 per surface of the steel sheet and a thickness of 0.060 μm to 0.500 μm per surface of the steel sheet. The metallic chromium layer includes a flat-like metallic chromium sublayer and a granular metallic chromium sublayer placed on a surface of the flat-like metallic chromium sublayer. The total chromium coating weight of both sublayers per surface of the steel sheet is 60 mg/m.sup.2 to 200 mg/m.sup.2. The chromium oxide layer has a chromium coating weight 3 mg/m.sup.2 to 10 mg/m.sup.2 per surface of the steel sheet in terms of metallic chromium.

A trivalent chromium plating solution containing a trivalent chromium compound, a complexing agent, a conductive salt, and a pH-buffering agent, and further containing an organic compound having 2-4 carbon atoms and three or more chloro groups, and a trivalent chromium plating method using the same provide a practical trivalent chromium plating with enhanced corrosion resistance as compared to the ordinary trivalent chromium plating.

Surface-treated copper foils exhibiting a void volume (Vv) in a range of 0.4 to 2.2 μm.sup.3/μm.sup.2 and an arithmetic mean waviness (Wa) lower than or equal to 0.4 μm are reported. Where the surface-treated copper foil is treated on the drum side and includes a treatment layer comprising a nodule layer. Such surface-treated copper foils can be used as a conductive material having low transmission loss, for example in circuit boards.

Surface-treated copper foils exhibiting a void volume (Vv) in a range of 0.4 to 2.2 μm.sup.3/μm.sup.2 and an arithmetic mean waviness (Wa) lower than or equal to 0.4 μm are reported. Where the surface-treated copper foil is treated on the drum side and includes a treatment layer comprising a nodule layer. Such surface-treated copper foils can be used as a conductive material having low transmission loss, for example in circuit boards.

A method for galvanic application of a surface coating, in particular a chromium coating, to a body, for example a machine component. Before the galvanic application of the surface coating, a layer of a compound that can be oxidized by an electrolyte solution that is used, preferably a polyhydroxy compound with a viscosity of at least 1000 mPas at 25° C., is applied to the body. A method for galvanic application of a surface coating, in particular a chromium coating, to a body, for example a machine component, wherein the surface coating is carried out in a closed reactor in an at least two-stage, preferably three-stage process, is also disclosed. An electrolyte solution contained in the reactor at a temperature T1 for carrying out a subsequent process stage is substituted by an electrolyte solution at a temperature T2≠T1. A device for carrying out this method is also disclosed.

A method for galvanic application of a surface coating, in particular a chromium coating, to a body, for example a machine component. Before the galvanic application of the surface coating, a layer of a compound that can be oxidized by an electrolyte solution that is used, preferably a polyhydroxy compound with a viscosity of at least 1000 mPas at 25° C., is applied to the body. A method for galvanic application of a surface coating, in particular a chromium coating, to a body, for example a machine component, wherein the surface coating is carried out in a closed reactor in an at least two-stage, preferably three-stage process, is also disclosed. An electrolyte solution contained in the reactor at a temperature T1 for carrying out a subsequent process stage is substituted by an electrolyte solution at a temperature T2≠T1. A device for carrying out this method is also disclosed.

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 Ni concentration of 0.1 to 15.0 atm % based on the total amount of elements of C, N, O, Zn, Cr, Ni, Co, Si, and Cu, in an XPS depth profile obtained by performing sputtering at a sputtering rate of 2.5 nm/min (in terms of SiO.sub.2) for 1 minute. 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.

This disclosure includes coatings for increasing the physical and/or chemical properties of articles, for example, tubular metal articles such as those found in the oil and gas industry, as well as processes for making such coatings and articles comprising such coatings.

This disclosure includes coatings for increasing the physical and/or chemical properties of articles, for example, tubular metal articles such as those found in the oil and gas industry, as well as processes for making such coatings and articles comprising such coatings.

The invention relates to an optical element including a resin body having a functional surface covered with a reflective coating capable of reflecting light beams, the reflective coating including a copper layer covering at least the functional surface, a nickel layer covering the copper layer, and a chromium layer covering the nickel layer.