Liquid ejection head and manufacturing method thereof

1 . A liquid ejection head comprising:

a nozzle plate where a nozzle for ejecting a liquid is provided;

a substrate including a piezoelectric element for generating pressure for ejecting the liquid from the nozzle; and

a wall member made of a resin and provided between the nozzle plate and the substrate to form a pressure chamber that communicates with the nozzle,

wherein a structure for connecting at least two side surfaces, among a plurality of side surfaces of the wall member that forms the pressure chamber, is provided,

wherein the liquid ejection head includes a plurality of the nozzles and a plurality of the pressure chambers each having a cuboid shape and respectively corresponding to the plurality of nozzles, and

wherein the liquid ejection head satisfies a relationship T/L>2, where L is a thickness of the wall member between the plurality of pressure chambers adjacent to each other in a short side direction of the plurality of pressure chambers and T is a height of the plurality of pressure chambers in a direction perpendicular to the substrate.

2 . The liquid ejection head according to claim 1 , wherein the pressure chamber is a space surrounded by the wall member, the nozzle plate, and the substrate.

3 . The liquid ejection head according to claim 1 , wherein the structure is formed integrally with the wall member using a same material as the wall member.

4 . The liquid ejection head according to claim 1 ,

wherein the cuboid shape is arranged in the short side direction of the plurality of pressure chambers, and

wherein, in a planar view in the direction perpendicular to the substrate, the structure continuously connects side surfaces of the wall member between the plurality of pressure chambers in the short side direction of the plurality of pressure chambers.

5 . The liquid ejection head according to claim 1 , wherein, in a planar view in the direction perpendicular to the substrate, the structure is arranged at both ends of the piezoelectric element in a long side direction thereof, the piezoelectric element having a rectangular shape.

6 . The liquid ejection head according to claim 1 , wherein the wall member and the structure are covered with a function film made of a material having a Young's modulus of 50 GPa or more.

7 . The liquid ejection head according to claim 1 , wherein the wall member is formed of two or more layers of a resin.

8 . The liquid ejection head according to claim 1 , wherein the nozzle plate and the wall member are formed integrally.

9 . The liquid ejection head according to claim 1 , further comprising a driving circuit configured to apply a driving electric signal for driving each of a plurality of the piezoelectric elements,

wherein the driving circuit includes common wiring for inputting the driving electric signal to two or more of the plurality of piezoelectric elements.

10 . A liquid ejection head comprising:

a plurality of nozzles configured to eject a liquid;

a plurality of pressure chambers each having a cuboid shape and respectively corresponding to the plurality of nozzles;

a nozzle plate including a nozzle of the plurality of nozzles;

a substrate including a piezoelectric element configured to generate pressure for ejecting the liquid; and

a wall member made of a resin including at least two side surfaces,

wherein the wall member is provided between the nozzle plate and the substrate to form a pressure chamber that communicates with at least one nozzle of the plurality of nozzles, and

wherein the wall member has a thickness (L) between adjacent pressure chambers in a short side direction and a height (T) in a direction perpendicular to the substrate, with T/L>2.