Mold production method

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.