Hitachi Maxell, Limited

Norihisa Yoshimoto

Masakazu Tani

Kenichiro Yoshida

Yoshiyuki Makita

Shoji Saibara

Hiroshi Kashino

Kohei Ugawa

In a membrane electrode assembly of the present invention, at least one of a catalyst layer of an oxygen electrode and a catalyst layer of a fuel electrode includes a supported catalyst supporting a metal catalyst containing a platinum group element, a proton conductive polymer electrolyte, and at least one selected from (a) a complex-forming agent having a ligand that forms coordinate bonds with ions of the platinum group element and forms a complex, the ligand containing oxygen as a coordinating atom, (b) a complex of the platinum group element, a ligand of the complex containing oxygen as a coordinating atom, and (c) carbon that has a BET specific surface area of 100 m/g or greater, satisfies at least one of (i) an R value of Raman spectrum of 0.5 or less and (ii) a lattice spacing dbetween (002) planes of 0.35 nm or less, and does not support the metal catalyst. With the use of the membrane electrode assembly of the present invention, it is possible to provide a polymer electrolyte fuel cell that has high durability and a long service life.

Membrane electrode assembly and polymer electrolyte fuel cell

A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, a magnetic layer formed on the primer layer, and a backcoat layer formed on the other surface of the non-magnetic support, wherein the magnetic layer has a thickness of 0.30 &#x3bc;m or less and a centerline average surface roughness Ra of 3.2 nm or less, and (P&#x2212;P) is 30 nm or less and (P&#x2212;P) is 5 nm or less in which Pis an averaged height of projections of the magnetic layer, and P, P, - - - and Pare heights of the highest, the second highest, - - - and the 20th highest projections of the magnetic layer, respectively.

Magnetic recording medium comprising a magnetic layer having specific thickness, surface roughness and projections

Magnetic recording medium comprising a magnetic layer having specific thickness and projections

A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, a magnetic layer formed on the primer layer, and a backcoat layer formed on the other surface of the non-magnetic support, wherein the magnetic layer has a thickness of 0.30 &#x3bc;m or less and a centerline average surface roughness Ra of 3.2 nm or less, and (P&#x2212;P) is 30 nm or less and (P-P) is 5 nm or less in which Pis an averaged height of projections of the magnetic layer, and P, P, - - - and Pare heights of the highest, the second highest, - - - and the 20th highest projections of the magnetic layer, respectively.

Magnetic recording medium comprising a magnetic layer having specific thickness, surface roughness and friction coefficient

A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, a magnetic layer formed on the primer layer, and a backcoat layer formed on the other surface of the non-magnetic support, wherein the magnetic layer has a thickness of 0.30 &mgr;m or less and a centerline average surface roughness Ra of 3.2 nm or less, and (P &minus;P ) is 30 nm or less and (P &minus;P ) is 5 nm or less in which P is an averaged height of projections of the magnetic layer, and P , P , - - - and P are heights of the highest, the second highest, - - - and the 20th highest projections of the magnetic layer, respectively.

Growing community of inventors

Kyoto-fu, Japan

Norihisa Yoshimoto