Patent ID: 8591005

Claim:
A liquid ejection head, comprising: an ejection face having a plurality of recessed portions formed therein, wherein the plurality of the recessed portions include: a first recessed portion having a bottom portion in which at least one ejection opening is formed for ejecting liquid and on which a liquid repellent layer is formed; and a second recessed portion having an opening end whose length in one direction parallel to the ejection face is the same as a length of an opening end of the first recessed portion in the one direction, and wherein the plurality of the recessed portions are formed such that, where a distance D 1 is a distance between (i) a one-side portion of an opening end of one recessed portion of the plurality of the recessed portions in the one direction and (ii) an other-side portion of an opening end of another recessed portion, in the one direction, adjacent to the one recessed portion on one side of the one recessed portion in the one direction without interposing any recessed portions between said another recessed portion and the one recessed portion and where a distance D 2 is a distance between (i) an other-side portion of the opening end of the one recessed portion in the one direction and (ii) a one-side portion of an opening end of another recessed portion, in the one direction, adjacent to the one recessed portion on the other side of the one recessed portion in the one direction without interposing any recessed portions between said another recessed portion and the one recessed portion, a large-and-small relationship of an average value of the distance D 1 and the distance D 2 of the second recessed portion with respect to an average value of the distance D 1 and the distance D 2 of the first recessed portion is the same as a large-and-small relationship of an area of a cross section of the first recessed portion which cross section is perpendicular to the ejection face and along the one direction, with respect to an area of a cross section of the second recessed portion which cross section is perpendicular to the ejection face and along the one direction.