Liquid ejection head and liquid ejection apparatus

A liquid ejection head comprising a liquid ejection unit in which a plurality of ejection modules are arrayed on a flow path forming member,

• wherein each of the ejection modules includes a recording element substrate and a support member supporting the recording element substrate,
• the recording element substrate includes
• a plurality of arrayed pressure chambers each including an ejection port from which a liquid is ejected, a recording element which is driven to eject the liquid from the ejection port, a supply port through which the liquid is supplied to the pressure chamber, and a collection port through which the liquid supplied to the pressure chamber is discharged from the pressure chamber after passing through the pressure chamber,
• a liquid supply channel communicating with each supply port of the plurality of pressure chambers, which is disposed on one side of an array of the ejection ports of the plurality of pressure chambers, and
• a liquid collection channel communicating with each collection port of the plurality of pressure chambers, which is disposed on another side of the array of the ejection ports,
• the support member includes at least two supply-side openings through which to supply the liquid to the liquid supply channel, and at least two collection-side openings through which to collect the liquid from the liquid collection channel,
• the plurality of ejection modules are arrayed on the flow path forming member such that each array of ejection ports of the plurality of ejection modules form an overall array of ejection ports as a whole,
• the flow path forming member includes
• a plurality of individual supply flow paths connected to the supply-side openings of the plurality of ejection modules,
• a plurality of individual collection flow paths connected to the collection-side openings of the plurality of ejection modules,
• a common supply flow path to which each of the plurality of individual supply flow paths is connected, and
• a common collection flow path to which each of the plurality of individual collection flow paths is connected,
• in each of the plurality of ejection modules, the supply-side openings communicating with the liquid supply channel are disposed on the one side of the array of the ejection ports whereas the collection-side openings communicating with the liquid collection channel are disposed on the other side of the array of the ejection ports,
• in one of two adjacent ejection modules among the plurality of ejection modules, the supply-side openings and the collection-side openings are alternately arranged in an order of a supply-side opening, a collection-side opening, a supply-side opening, and a collection-side opening from one end toward the other end in a direction in which the ejection ports are arrayed, and
• in the other of the two adjacent ejection modules, the supply-side openings and the collection-side openings are alternately arranged in an order of a collection-side opening, a supply-side opening, a collection-side opening, and a supply-side opening from the one end toward the other end in the direction in which the ejection ports are arrayed.