Patent ID: 6971736

Claim:
An ink jet record head comprising: said head has: a flow path composition substrate having a plurality of nozzles through which liquid flows, a supply chamber for supplying the liquid to each of the nozzles, and a plurality of discharge ports which are nozzle end openings for discharging a liquid droplet, said nozzle comprised of a bubbling chamber in which bubble is generated by a discharge energy generating element for generating thermal energy for discharging the liquid droplet, discharge port portions including said discharge ports and communicating between said discharge ports and said bubbling chamber, and a supply path for supplying the ink to the bubbling chamber; and an element substrate on which said discharge energy generating element is provided and joining said flow path composition substrate with a principal surface, wherein said discharge port portion has: a first discharge port portion including said discharge port and having a cross section approximately constant against a discharge axis; and a second discharge port portion contiguous to the first discharge port portion with an uneven portion and communicating with said bubbling chamber while having the cross section parallel with the principal surface of said element substrate and larger than the cross section of the first discharge port portion, and a distance of the uneven portion farthest from a supply direction of said second discharge port portion is shorter than the distance of said uneven portion in an arrangement direction of said discharge ports.