Patent ID: 7384130

Claim:
A liquid ejection head comprising: an energy generation element for generating energy for ejecting liquid droplets; a chamber having said energy generation element; a supply path communicating with said chamber for supplying a liquid to said chamber; an ejection port facing a surface on which said energy generation element is disposed; and an ejection portion having said ejection port, wherein said ejection portion comprises a first portion communicating with said ejection port and a second portion communicating with said first portion and said chamber, wherein said first portion, said second portion and said chamber are respectively connected in a stair-like pattern, and wherein A c >A e2 A e1 , where A c =a cross-sectional area of said chamber, the cross-sectional area being parallel to the surface on which said energy generation element is disposed, A e2 =a cross-sectional area of said second portion, the cross-sectional area being parallel to the surface on which said energy generation element is disposed, and A e1 =a cross-sectional area of said first portion, the cross-sectional area being parallel to the surface on which said energy generation element is disposed.