Liquid ejection recording head having element substrate with plural supply ports

Abstract

A liquid ejection recording head includes an element substrate having plural ejection energy generating elements, an ejection outlet array of plural ejection outlets, and bubble generation chambers. The element substrate includes a first liquid supply port provided along an arrangement direction of the ejection outlets, and plural second ink supply ports disposed between a lateral end of the substrate and the chambers. Each bubble generation chamber communicates with the first and second liquid supply ports through first and second liquid supply passages, respectively. The element substrate has a thermal resistance against heat flowing from the ejection energy generating elements along a direction perpendicular to the array direction and parallel to a surface of the substrate. The thermal resistance, per unit length with respect to the array direction, at both end portions of the array is larger than that at a central portion of the ejection outlet array.