Liquid ejection head including a plurality of recording element substrates formed adjacent to each other to form an array such that a gap in temperature distribution is prevented

A liquid ejection head in which at least two ejection modules are arrayed adjacently on a flow path forming member, each of the ejection modules including a support member, a lid member and a recording element substrate which are laid sequentially on one another, wherein

• the recording element substrate includes an ejection port array including a plurality of ejection ports arrayed in a direction in which a first ejection module and a second ejection module are arrayed adjacently and a liquid supply channel and a liquid collection channel each extending in the direction on one and the other sides of the ejection port array respectively as sandwiching the ejection port array,
• the liquid ejection head includes two or more supply-side liquid communication paths each comprising a communication port provided in a flow path member constituting the flow path forming member, a liquid communication port provided in the support member and an opening provided in the lid member through which to supply a liquid to the liquid supply channel, and the same number of collection-side liquid communication paths each comprising a communication port provided in the flow path member, a liquid communication port provided in the support member and an opening provided in the lid member through which to collect the liquid from the liquid collection channel,
• the supply-side liquid communication paths and the collection-side liquid communication paths are alternately arranged along the direction such that the ejection port array is sandwiched between one of the supply-side liquid communication paths and one of the collection-side liquid communication paths, and
• the liquid ejection head is configured such that two of the supply-side liquid communication paths or two of the collection-side liquid communication paths are arranged close to adjacent ends of the first and second ejection modules.