Patent attributes
The print head includes an energy generating element, a chamber for accommodating liquid, and an ejection opening arranged in a position corresponding to the energy generating element. The ejection opening includes at least one projection projecting inside of the ejection opening, the ejection opening having a first region between a front end of the projection and an inner wall of the ejection opening positioned at the shortest distance from the front end, and second regions positioned on both sides of the projection and different from the first region, and when a width of the projection at a chamber-side opening face is represented as a1 and the maximum width of the projection is represented as a2, a relation a1<a2 is established and the width of the projection decreases gradually or step by step from a position having the width of a2 to the chamber-side opening face.