Polymer electrolyte membrane, membrane-electrode assembly for polymer electrolyte fuel cells and process for producing polymer electrolyte membrane

A polymer electrolyte membrane characterized by comprising at least one layer of a perforated sheet comprising a region 1 wherein many through-holes are formed substantially in parallel to the thickness direction with an average cross-sectional area per hole of from 1×10−3 to 20 mm2, and the numerical aperture based on the through-holes is from 30 to 80%, and a region 2 which is a peripheral portion of the above region 1 and which has a lower numerical aperture than the above region 1 or has no through-holes, and wherein an ion exchange resin is filled in the through-holes.

A membrane-electrode assembly for polymer electrolyte fuel cells, which comprises a polymer electrolyte membrane and a catalyst layer containing a catalyst disposed on each side of the polymer electrolyte membrane, characterized in that the electrolyte membrane comprises at least one layer of a perforated sheet having many through-holes formed substantially in parallel to the thickness direction with an average cross-sectional area per hole of from 1×10−3 to 20 mm2, wherein the numerical aperture based on the through-holes is from 30 to 80%, and an ion exchange resin is filled in the through-holes.

A membrane-electrode assembly for polymer electrolyte fuel cells, which comprises a polymer electrolyte membrane and a catalyst layer containing a catalyst disposed on each side of the polymer electrolyte membrane, characterized in that the electrolyte membrane comprises at least one layer of a perforated sheet comprising a region 1 wherein many through-holes are formed substantially in parallel to the thickness direction with an average cross-sectional area per hole of from 1×10−3 to 20 mm2, and the numerical aperture based on the through-holes is from 30 to 80%, and a region 2 which is a peripheral portion of the above region 1 and which has a lower numerical aperture than the above region 1 or has no through-holes, and wherein an ion exchange resin is filled in the through-holes.

A process for producing a polymer electrolyte membrane reinforced by a perforated sheet, characterized by applying a coating fluid containing an ion exchange resin to a perforated sheet having many through-holes formed substantially in parallel to the thickness direction with an average cross-sectional area per hole of from 1×10−3 to 20 mm2, wherein the numerical aperture based on the through-holes is from 30 to 80%, to fill the through-holes with the ion exchange resin.

A process for producing a polymer electrolyte membrane reinforced by a perforated sheet, characterized by heat pressing a membrane made of an ion exchange resin to a perforated sheet having many through-holes formed substantially in parallel to the thickness direction with an average cross-sectional area per hole of from 1×10−3 to 20 mm2, wherein the numerical aperture based on the through-holes is from 30 to 80%, to inject and fill the ion exchange resin in the through-holes.

A process for producing a polymer electrolyte membrane reinforced by a perforated sheet, characterized by applying a coating liquid containing an ion exchange resin to a perforated sheet comprising a region 1 wherein many through-holes are formed substantially in parallel to the thickness direction with an average cross-sectional area per hole of from 1×10−3 to 20 mm2, and the numerical aperture based on the through-holes is from 30 to 80%, and a region 2 which is a peripheral portion of the region 1 and which has a lower numerical aperture than the region 1 or has no through-holes, to fill the through-holes with the ion exchange resin.

A process for producing a polymer electrolyte membrane reinforced by a perforated sheet, characterized by heat pressing a membrane made of an ion exchange resin to a perforated sheet comprising a region 1 wherein many through-holes are formed substantially in parallel to the thickness direction with an average cross-sectional area per hole of from 1×10−3 to 20 mm2, and the numerical aperture based on the through-holes is from 30 to 80%, and a region 2 which is a peripheral portion of the region 1 and which has a lower numerical aperture than the region 1 or has no through-holes, to inject and fill the ion exchange resin in the through-holes.