Abstract: A water electrolyzer includes an electrochemical cell including an anode and a cathode, an electrolyte solution, a heater, a voltage applicator, and a controller. The heater heats the electrolyte solution. The voltage applicator applies a voltage between the anode and the cathode. The electrochemical cell includes nickel. In startup of the water electrolyzer, the controller causes the heater to increase the temperature of the electrolyte solution by heating and causes the voltage applicator to start application of a voltage when the temperature of the electrolyte solution is less than a predetermined threshold value.

Abstract: A water electrolysis cell includes an anode, a cathode, and an anion-exchange membrane disposed between the anode and the cathode. The anode includes a catalyst layer disposed on the anion-exchange membrane and an anode gas diffusion layer disposed on the catalyst layer. The anode gas diffusion layer includes metal fiber. In the metal fiber, a section constituting a surface of the metal fiber is composed of nickel.

Abstract: A water electrolyzer includes an electrochemical cell including an anode and a cathode, an electrolyte solution, a voltage applicator, and a controller. The voltage applicator applies a voltage between the anode and the cathode. The electrochemical cell includes nickel. In the shutdown of the water electrolyzer, the controller causes the voltage applicator to apply the voltage at least when the temperature of the electrolyte solution is equal to or more than a predetermined threshold value.

Abstract: The electrode catalyst ink for a water electrolysis cell includes a catalyst including a layered double hydroxide, an organic polymer, and a solvent. The Hansen solubility parameter distance Ra1 between the solvent and the catalyst is 15.0 MPa½ or more and less than 20.5 MPa½. The Hansen solubility parameter distance Ra2 between the solvent and the organic polymer is 10.0 MPa½ or more and 14.0 MPa½ or less.

Abstract: The electrode catalyst ink includes a catalyst including a layered double hydroxide, an organic polymer, and a solvent. The solvent includes a first solvent, a second solvent, and a third solvent. The third solvent has a boiling point higher than a boiling point of the first solvent and higher than a boiling point of the second solvent. The Hansen solubility parameter distance Ra1 [MPa1/2] between the third solvent and the catalyst and the Hansen solubility parameter distance Ra2 [MPa1/2] between the third solvent and the organic polymer satisfy a relationship of 2.08Ra1?16.0?Ra2?2.08Ra1?13.5.

Abstract: An electrode catalyst for a water electrolysis cell includes a catalyst, and a polymer of intrinsic microporosity having a Tröger's base skeleton containing a quaternary ammonium group. A water electrolysis cell includes an anode, a cathode, and an electrolyte membrane. The electrolyte membrane is disposed between the anode and the cathode. At least one selected from the group consisting of the anode and the cathode includes the electrode catalyst.

Abstract: An electrode catalyst for a water electrolysis cell includes a catalyst and a polymer of intrinsic microporosity, and the polymer of intrinsic microporosity is neutral.

Abstract: An electrode catalyst for a water electrolysis cell includes a catalyst, a support, and an organic compound. The catalyst is a layered double hydroxide that contains a chelating agent. The support contains a transition metal. The organic compound has an anionic functional group.

Abstract: A manufacturing method for a perpendicular magnetic recording head includes the steps of forming a groove in a first nonmagnetic layer, forming a side shield, forming a second nonmagnetic layer, forming a main-magnetic-pole front end portion and forming a main-magnetic-pole yoke portion. The groove extends in a front-rear direction orthogonal to an air bearing surface. The side shield of soft magnetic material, the second nonmagnetic layer and the main-magnetic-pole front end portion of soft magnetic material are formed on an inner wall of the groove. The main-magnetic-pole front end portion is not magnetostatically coupled to the side shield. The main-magnetic-pole yoke portion magnetically is insulated from the side shield and magnetically connected to the main-magnetic-pole front end portion. The main-magnetic-pole yoke portion widens from the main-magnetic-pole front end portion toward a rear side.

Abstract: The magnetic head is capable of preventing variation of magnetic fields working to a read-element, stably generating output signals and improving production yield. The magnetic head comprises: a read-head including a read-element; and a shield for magnetic-shielding the read-element, the shield has a hexagonal planar shape, and one side of the shield is flush with an air bearing surface of the magnetic head.

Abstract: The perpendicular magnetic head is capable of solving the problem of pole-erasing and performing high density recording by a main magnetic pole. The perpendicular magnetic head comprises a write-head including a main magnetic pole, and the main magnetic pole is a magnetic thin film having magnetic anisotropy, in which a magnetizing direction is parallel to a recording surface of a recording medium.

Abstract: The perpendicular magnetic head is capable of solving the problems of side track erasing and pole erasing. The perpendicular magnetic head of the present invention comprises a write-head, which includes a main magnetic pole emitting magnetic fluxes toward a recording medium. An end face of a pole end is formed into a T-shape. A longitudinal pole section of the pole end is made of a low Bs magnetic thin film, whose end face is formed into a rectangle. A transverse pole section of the pole end is made of a high Bs magnetic thin film, whose end face is formed into a rectangle. The low Bs magnetic thin film and the high Bs magnetic thin film are determined by the formula: (area of the end face of the low Bs magnetic thin film)×(saturation magnetic flux density of the low Bs magnetic thin film)>(area of the end face of the high Bs magnetic thin film)×(saturation magnetic flux density of the high Bs magnetic thin film).

Abstract: A method for manufacturing a magnetoresistance head of the present invention comprises the steps of forming an organic film on a multilayered film constituting a magnetoresistance device, forming an upper film formed of resist or inorganic film on the organic film, patterning the organic film and the upper film, cutting into edges of the organic film patterns from edges of the upper film patterns inwardly to such an extent that particles of the thin film being formed on the upper film and the multilayered film do not contact to side portions of the organic film patterns.

Abstract: A method for manufacturing a magnetoresistance head of the present invention comprises the steps of forming an organic film on a multilayered film constituting a magnetoresistance device, forming an upper film formed of resist or inorganic film on the organic film, patterning the organic film and the upper film, cutting into edges of the organic film patterns from edges of the upper film patterns inwardly to such an extent that particles of the thin film being formed on the upper film and the multilayered film do not contact to side portions of the organic film patterns.

Abstract: A method for manufacturing a magnetoresistance head of the present invention comprises the steps of forming an organic film on a multilayered film constituting a magnetoresistance device, forming an upper film formed of resist or inorganic film on the organic film, patterning the organic film and the upper film, cutting into edges of the organic film patterns from edges of the upper film patterns inwardly to such an extent that particles of the thin film being formed on the upper film and the multilayered film do not contact to side portions of the organic film patterns.