Patent ID: 8790849

Claim:
A method for manufacturing an electrode catalyst layer, comprising: containing a conductive carrier on which a catalyst is supported, a substrate, an electrolyte resin, and a supercritical fluid inside a closed container, wherein the catalyst is supported on the conductive carrier prior to being introduced into the container; providing temperature and pressure conditions inside the closed container to place the supercritical fluid in a supercritical state above a critical point; dissolving the electrolyte resin in the supercritical fluid when the supercritical fluid is in the supercritical state; and cooling the substrate to or below the critical point and thereby changing the supercritical state of the supercritical fluid into a liquid state and thereby precipitating the electrolyte resin near the substrate to form the electrode catalyst layer on the substrate, wherein the electrode catalyst layer formed on the substrate comprises the conductive carrier, the catalyst supported on the conductive carrier, and the electrolyte resin wherein the supercritical fluid only around the conductive carrier is changed into the liquid state and the other supercritical fluid is maintained in the supercritical state during a period when the electrode catalyst layer is formed on the substrate.