Patent ID: 9366785
Filing Date: 2016-06-14
CPC Classification: B29C,C25D,G02B

Claim Text:
1. A method of fabricating a mold that has an inverted moth-eye structure in its surface, the inverted moth-eye structure having a plurality of recessed portions whose two-dimensional size viewed in a direction normal to the surface is not less than 50 nm and less than 500 nm, the method comprising the steps of: (a) providing an aluminum film deposited on a base, the aluminum film having a thickness of not less than 0.5 μm and not more than 5 μm, a surface of the aluminum film having a plurality of crystal grains whose crystal grain diameter distribution has two local maximums, the larger one of the local maximums being not less than 200 nm; (b) after step (a), anodizing the surface of the aluminum film to form a porous alumina layer which has a plurality of minute recessed portions; and (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.