POROUS LAYER AND MANUFACTURING METHOD OF THE SAME (AS AMENDED)

摘要

A manufacturing method of porous layer comprises: drying a mixed solution containing conductive carbon powder and water-repellent resin powder by a spray-drying method, so as to produce a powdery substance including the conductive carbon powder coated with the water-repellent resin powder; and producing the porous layer from the powdery substance. Water-vapor permeability of the porous layer measured in conformity with the Japanese Industrial Standard ES-Z-0208 is 10000 to 25000 g/m2·24 h under conditions of temperature of 40° C. and relative humidity of 90% RH.

主权项

1. A manufacturing method of porous layer that produces a porous layer stacked between a catalyst layer and a gas diffusion layer in a membrane electrode assembly of a fuel cell, the manufacturing method comprising:
(a) process of drying a mixed solution containing conductive carbon powder and water-repellent resin powder by a spray-drying method, so as to produce a powdery substance including the conductive carbon powder coated with the water-repellent resin powder; and (b) process of producing the porous layer from the powdery substance produced by the process (a), such that water-vapor permeability of the porous layer measured in conformity with the Japanese Industrial Standard JIS-Z-0208 is 10000 to 25000 g/m2·24 h under conditions of temperature of 40° C. and relative humidity of 90% RH.