Mold manufacturing method and anti-reflective film manufacturing method

A manufacturing method of a mold, the mold having at its surface a plurality of recessed portions whose two-dimensional size is not less than 10 nm and less than 500 nm when viewed in a direction normal to the surface, the method comprising:

• (a) providing a mold base which includes a metal base and an aluminum alloy layer formed on the metal base, the aluminum alloy layer having at its surface an attached object including aluminum;
• (b) partially anodizing the aluminum alloy layer, thereby forming 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;
• (d) detecting a protrusion including the attached object formed at a surface of the porous alumina layer;
• (e) determining whether or not a height of the protrusion detected at step (d) is greater than a predetermined height;
• and
• (f) if it is determined at step (e) that the height of the protrusion is greater than the predetermined height, irradiating the protrusion with laser light such that the height of the protrusion becomes smaller than the predetermined height, wherein
• step (d), step (e) and step (f) are performed after step (b) and step (c).