Ink jet head cartridge, print head, ink container, and method for manufacturing ink jet head cartridge

An ink container, comprising:

• a joint member jointed with a printing element substrate, wherein the printing element substrate includes a first ink supply opening being elongated in a longitudinal direction and supplies ink to an ejection port and to an energy application element for applying energy to ink;
• wherein the joint member defines a second ink supply opening being a through hole which communicates with the first ink supply opening at a joint area therebetween, a plurality of the second ink supply openings being formed along the longitudinal direction of the first ink supply opening;
• an ink containing portion storing ink therein which communicates with the second ink supply opening;
• and
• a beam member formed, by flowing a resin including a filler material along a crossing direction crossing the longitudinal direction of the first ink supply opening, at a position between the plurality of the second ink supply openings.