Patent ID: 8312628

Claim:
A method for manufacturing a liquid discharge head including: an element substrate in which an element configured to generate energy required to discharge liquid from a discharge port, power line electrically connected to the element, and a terminal electrically connected to the power line and configured to electrically connect to an external unit are provided on a substrate; and a member made of resin having a wall of a liquid flow path communicating with the discharge port, the flow path being formed by the element substrate and the member that are in contact with each other with the wall facing inwardly, a surface layer of the power line being in contact with the member, the method comprising: preparing the element substrate including materials of the power line and the terminal, the power line materials including a first precious metal layer made of precious metal on the substrate, a first nickel layer made of nickel on the first precious metal layer, and a third precious metal layer made of precious metal on the first nickel layer, the terminal including a second precious metal layer made of precious metal on the substrate, a second nickel layer made of nickel on the second precious metal layer, and a fourth precious metal layer made of precious metal on the second nickel layer; and heating the first nickel layer and the third precious metal layer of the power line materials to form the surface layer made of an alloy of precious metal and nickel.