Patent ID: 7004569

Claim:
An electrothermal converting element board comprising: an electrothermal converting element layer having a plurality of heat generating sections arranged on one straight line in correspondence to a plurality of liquid flowing paths, each having a liquid ejection opening for ejecting liquid used for a printing at one end thereof; a common electrode layer connected to said plurality of heat generating sections of said electrothermal converting element layer, wherein said common electrode layer is formed via a first insulating layer beneath said plurality of heat generating sections of said electrothermal converting element; an individual electrode layer electrically connected to at least one of said plurality of heat generating sections of said electrothermal converting element layer and formed beneath said common electrode layer via a second insulating layer; and a base section that supports said electrothermal converting element layer, said common electrode layer and said individual electrode layer, wherein said first insulating layer, said common electrode layer, said second insulating layer and said individual electrode layer are laminated in sequence beneath said heat generating sections.