Abstract: A method for manufacturing Cu—Sn coexisting steel produces a good quality surface even after hot rolling. The steel is manufactured by continuous casting a molten steel that contains C: 0.04 to 0.20%, Si: 0.05 to 1.00%, Mn: 0.20 to 2.50%, P: no more than 0.05%, S: no more than 0.02%, Cu: 0.20 to 1.50%, Sn: 0.06 to 0.50%, Al: 0.06 to 1.00% and Ni: 0.05 to 1.00% by mass, and Fe and impurities as the remainder. The composition of the molten steel is defined as [Al]/(3[Si]+[Mn])?0.050, [Ni]/([Cu]+5[Sn])?0.10 and [Al]/[Ni]?0.20 if the content of an element X in the molten steel is represented as [X], an internal oxidation layer is formed in a process of cooling a slab, and Al2O3 is contained by the internal oxidation layer.

Abstract: A liquid discharge head including a substrate, and an energy-generating element. The substrate is provided with a flow path that penetrates through the substrate from the first surface to a second surface, the flow path supplying the liquid from the second surface side to the first surface side. The flow path includes a plurality of first flow paths and a second flow path that is positioned on the second surface side with respect to the first flow paths. The plurality of first flow paths are open on a bottom portion of the second flow path, and the plurality of first flow paths include a long flow path relatively long in a direction perpendicular to the first surface, and a relatively short flow path. The long flow path has a flow path resistance per unit length that is smaller than that of the short flow path.

Abstract: In a threaded joint for pipes constituted by a pin and a box, each having a contact surface comprising a threaded portion and an unthreaded metal contact portion, the contact surface of the pin has a solid corrosion protective, preferably transparent coating based on a UV-curable resin and the contact surface of the box has a solid lubricating coating having plastic or viscoplastic rheological behavior which is preferably formed by the hot melt technique from a composition comprising a thermoplastic polymer, a wax, a metal soap, a corrosion inhibitor, a water-insoluble liquid resin, and a solid lubricant.

Abstract: A method of making a semiconductor substrate having a through-hole includes a step of forming an etching mask on a semiconductor substrate in accordance with a pattern corresponding to the through-hole, and a step of forming the through-hole by etching the semiconductor substrate, on which the etching mask has been formed, by reactive ion etching. At least a part of the pattern corresponding to the through-hole is formed so that the semiconductor substrate is exposed in a frame-like shape along the inner edge of the through-hole.

Abstract: A thin and highly transparent coating having excellent air tightness, adhesion to a substrate, lubricating properties, galling resistance, and corrosion resistance is formed on the surface of a metal substrate and particularly on the surface of a threaded joint which is used for connection of oil country tubular goods. A photocurable composition comprising (A) a photocurable (meth)acrylate resin, (B) a (meth)acrylate monomer selected from a monofunctional (meth)acrylate monomer and a difunctional (meth)acrylate monomer, (C) a trifunctional or higher multifunctional (meth)acrylate monomer, (D) a photopolymerization initiator, (E) a benzotriazole anticorrosive agent, (F) an anticorrosive pigment selected from a phosphate anticorrosive pigment and calcium ion-exchanged silica, and (G) a phosphate ester is used to form a photocured coating.

Abstract: A thin and highly transparent coating having excellent air tightness, adhesion to a substrate, lubricating properties, galling resistance, and corrosion resistance is formed on the surface of a metal substrate and particularly on the surface of a threaded joint which is used for connection of oil country tubular goods. A photocurable composition comprising (A) a photocurable (meth)acrylate resin, (B) a (meth)acrylate monomer selected from a monofunctional (meth)acrylate monomer and a difunctional (meth)acrylate monomer, (C) a trifunctional or higher multifunctional (meth)acrylate monomer, (D) a photopolymerization initiator, (E) a benzotriazole anticorrosive agent, (F) an anticorrosive pigment selected from a phosphate anticorrosive pigment and calcium ion-exchanged silica, and (G) a phosphate ester is used to form a photocured coating.

Abstract: In a threaded joint for pipes constituted by a pin and a box, each having a contact surface comprising a threaded portion and an unthreaded metal contact portion, the contact surface of the pin has a solid corrosion protective, preferably transparent coating based on a UV-curable resin and the contact surface of the box has a solid lubricating coating having plastic or viscoplastic rheological behavior which is preferably formed by the hot melt technique from a composition comprising a thermoplastic polymer, a wax, a metal soap, a corrosion inhibitor, a water-insoluble liquid resin, and a solid lubricant.