Patent ID: 9512535
Filing Date: 2016-12-06
CPC Classification: B29C,C25D,G02B

Claim Text:
1. A method for manufacturing a mold which has an inverted moth-eye structure over its surface, the inverted moth-eye structure having a plurality of recessed portions whose two-dimensional size viewed in a direction normal to its surface is not less than 10 nm and less than 500 nm, the method comprising the steps of: (a) providing a mold base, the mold base including a metal base, an organic insulating layer provided on the metal base, and an aluminum alloy layer provided on the organic insulating layer, the aluminum alloy layer containing aluminum and a non-aluminum metal element M, an absolute value of a difference between a standard electrode potential of the metal element M and a standard electrode potential of aluminum being not more than 0.64 V, and a content of the metal element M in the aluminum alloy layer not exceeding 10 mass %; (b) partially anodizing the aluminum alloy layer to form a porous alumina layer which has a plurality of minute recessed portions; (c) after step (b), bringing the porous alumina layer into contact with an etching solution, thereby enlarging the plurality of minute recessed portions of the porous alumina layer; and (d) after step (c), further performing anodization to grow the plurality of minute recessed portions, wherein the mold base further includes an inorganic underlayer interposed between the organic insulating layer and the aluminum alloy layer, and wherein the mold base further includes a buffer layer interposed between the inorganic underlayer and the aluminum alloy layer, the buffer layer containing aluminum, the metal element M, and either of oxygen or nitrogen.