US 12,220,918 B2
Liquid ejection head
Manabu Otsuka, Kanagawa (JP)
Assigned to Canon Kabushiki Kaisha, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Nov. 18, 2022, as Appl. No. 18/057,097.
Claims priority of application No. 2021-192914 (JP), filed on Nov. 29, 2021.
Prior Publication US 2023/0166507 A1, Jun. 1, 2023
Int. Cl. B41J 2/14 (2006.01)
CPC B41J 2/14274 (2013.01) [B41J 2002/14475 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A liquid ejection head comprising:
a first substrate having a first surface and a second surface opposite the first surface, the first surface having a structure;
a second substrate having a second surface facing the first surface of the first substrate; and
a third substrate having a first surface facing the second surface of the first substrate,
the first substrate and the second substrate being joined together by an adhesive located between the first surface of the first substrate and the second surface of the second substrate,
the first substrate and the third substrate being joined together by the adhesive located between the second surface of the first substrate and the first surface of the third substrate,
the second surface of the first substrate having an opening that is located in a region on a rear side of the structure and that has corners each having a curvature radius R2,
the second surface of the second substrate having an opening that is located in a region facing the structure and that has corners each having a curvature radius R1,
the curvature radii R1 and R2 satisfying R1<R2,
wherein
the second substrate further has a through-hole extending through the second substrate and including a stepped portion,
the through-hole including the stepped portion has an opening that is located at the second surface of the second substrate and that has corners each having a curvature radius R3, and
the curvature radii R1, R2, and R3 satisfy R3≤R1<R2.