Abstract: A liquid discharge head includes a nozzle substrate and a cover member. The nozzle substrate includes a liquid discharge surface, a plurality of nozzles, and a continuous recess. The plurality of nozzles is arranged in a nozzle arrangement area on the liquid discharge surface and configured to discharge liquid from the liquid discharge surface. The continuous recess surrounds the nozzle arrangement area on the liquid discharge surface. The cover member is joined to the nozzle substrate with the nozzle arrangement area being exposed. The nozzle arrangement area has a liquid repellency with respect to the liquid. An inside of the recess is lyophilic to the liquid and is provided with an adhesive, and the nozzle substrate is joined to the cover member with the adhesive.

Abstract: A liquid discharge head includes a nozzle substrate and a cover member. The nozzle substrate includes a liquid discharge surface, a plurality of nozzles, and a continuous recess. The plurality of nozzles is arranged in a nozzle arrangement area on the liquid discharge surface and configured to discharge liquid from the liquid discharge surface. The continuous recess surrounds the nozzle arrangement area on the liquid discharge surface. The cover member is joined to the nozzle substrate with the nozzle arrangement area being exposed. The nozzle arrangement area has a liquid repellency with respect to the liquid. An inside of the recess is lyophilic to the liquid and is provided with an adhesive, and the nozzle substrate is joined to the cover member with the adhesive.

Abstract: A metal member includes an alloy containing platinum-group metal. An amount of the platinum-group metal in an outermost surface of the metal member is higher than the amount of the platinum-group metal in an interior of the metal member.

Abstract: A metal member includes an alloy containing platinum-group metal. An amount of the platinum-group metal in an outermost surface of the metal member is higher than the amount of the platinum-group metal in an interior of the metal member.

Abstract: A liquid discharge head includes a channel plate. The channel plate includes a fluid restrictor, a channel, a first plate member, and a second plate member. The channel is disposed on at least one of an upstream side and a downstream side of the fluid restrictor in a direction of flow of liquid. The channel has a greater width than a width of the fluid restrictor in a direction perpendicular to the direction of flow of liquid in an in-plane direction. The first plate member has a through hole including at least one broad portion and a narrow portion. The narrow portion is the fluid restrictor. The second plate member includes at least one through hole constituting part of the channel with the broad portion. The through hole is disposed opposite an end of the narrow portion at which the narrow portion is connected to the broad portion.

Abstract: A liquid discharge head includes a channel plate. The channel plate includes a fluid restrictor, a channel, a first plate member, and a second plate member. The channel is disposed on at least one of an upstream side and a downstream side of the fluid restrictor in a direction of flow of liquid. The channel has a greater width than a width of the fluid restrictor in a direction perpendicular to the direction of flow of liquid in an in-plane direction. The first plate member has a through hole including at least one broad portion and a narrow portion. The narrow portion is the fluid restrictor. The second plate member includes at least one through hole constituting part of the channel with the broad portion. The through hole is disposed opposite an end of the narrow portion at which the narrow portion is connected to the broad portion.