摘要 |
A nonwoven fabric comprising a flame-retardant acrylic fiber, characterized in that it has a weight per square-meter of 70 to 190 g/m2, a thickness of 0.1 to 0.3 mm, a density of 0.35 to 0.8 g/cm3; and a nonwoven fabric comprising a carbon fiber, characterized in that it has a weight per square-meter of 50 t o 150 g/m2, a thickness of 0.1 to 0.25 mm, a density of 0.3 to 0.7 g/m3, a surface roughness Ra of 30 .mu.m or less, a tensile strength of 0.2 kgf/cm o r more, and a maximum fracture radius being defined in the specification of 20 mm or less. Said carbon fiber nonwoven fabric is produced by subjecting the above flame-retardant acrylic fiber to a carbonization treatment and can be suitably used as a material for forming an electrode of a fuel cell. |