Patent ID: 9731503
Date: 2017-08-15
CPC Classifications: B41J

Claim:
1. A liquid discharge head, comprising: a substrate member including a silicon substrate layer, a discharge element that discharges liquid by generating thermal energy to generate an air bubble in the liquid, a liquid supply port for supplying the liquid to the discharge element, and a protection layer including metal which is formed so as to cover the discharge element; a flow path forming member provided on a side of a surface of said substrate member on which the protection layer is provided and defining, between said substrate member and said flow path forming member, a pressure chamber comprising a heating portion of a surface of the protection layer that overlaps the discharge element in a perpendicular direction that is perpendicular to the surface of said substrate member and a flow path communicating between the pressure chamber and the liquid supply port and extending along the surface of said substrate member, said flow path forming member having a plurality of pressure chamber walls being perpendicular to the surface of said substrate member to form the pressure chamber and two flow path walls being perpendicular to the surface of said substrate member and opposed to each other to form the flow path; and an interlayer provided on a joining portion of said substrate member and said flow path forming member and including resin, wherein the plurality of pressure chamber walls are disposed in a rectangular shape so as to surround the heating portion except at a communication portion where the pressure chamber communicates with the flow path when viewed from the perpendicular direction, a distance between two pressure chamber walls of the plurality of pressure chamber walls on which the communication portion with the flow path is not provided and which are opposed to each other is greater than a distance between the two flow path walls, and said interlayer is provided on a portion of the flow path on a side of the liquid supply port and, an edge surface of said interlayer is located in a middle portion of the flow path with respect to a direction from the liquid supply port toward the pressure chamber such that the flow path has a portion, adjacent to the pressure chamber, where said interlayer is not provided and a step is formed by the edge surface of said interlayer in the flow path.