Patent ID: 7934813

Claim:
A liquid ejection head comprising: a head main body including: a cavity unit including a passage forming base plate forming a liquid passage from a common liquid chamber to a nozzle opening via a pressure chamber; and a pressure generating source generating a change of pressure of liquid in the pressure chamber to eject the liquid in the pressure chamber as a liquid droplet from the nozzle opening; and a case member to which the head main body is attached and which includes: a first member provided with a first atmosphere opening passage; and a second member laminated on the first member and provided with a second atmosphere opening passage, wherein the first and second atmosphere opening passages communicate with each other under the laminated state and are opened to atmosphere; wherein the first and second atmosphere opening passages pass through the first and second members respectively; wherein a third atmosphere opening passage is provided at a boundary between the first and second members; and wherein the first and second atmosphere opening passages which are opened at different positions in the boundary are communicated with each other through the third atmosphere opening passage.