Liquid ejection head

A liquid ejection head comprising:

• a substrate including an energy generating element;
• a nozzle plate including an ejection port configured to open at a position facing the energy generating element;
• a flow-path forming member stacked between the substrate and the nozzle plate, the flow-path forming member including a flow path wall demarcating a liquid flow path including a pressure chambers containing the energy generating element and the ejection port;
• wherein the flow path wall includes:
• a linear portion extending in a first direction perpendicular to the substrate;
• a first connection portion provided on one side of the linear portion in the first direction and configured to connect to the substrate;
• and
• a second connection portion provided on an other side of the linear portion in the first direction and configured to connect to the nozzle plate,
• wherein at least one of the first connection portion and the second connection portion includes a contact surface enlarging portion that protrudes toward an inner side of the liquid flow path in a second direction intersecting the first direction, further than the linear portion, and is thicker than the linear portion in the second direction.