ENDMILL FOR CUTTING OPTICAL FILM AND OPTICAL FILM MANUFACTURING METHOD USING SAID END MILL

摘要

Provided is an endmill capable of suppressing napping during an optical film cutting process. This endmill for cutting optical film has a main body that rotates about a rotation axis, and n number of cutting blades that protrude from the main body so as to constitute the most radially outward part thereof. The endmill also satisfies any one of the following conditions (1)-(3): (1) n is 1; (2) n is 2 or greater and the maximum value of the difference between the blade lengths of all the cutting blades is 0.12% or less with respect to a reference blade length; or (3) n is 2 or more and the minimum value of the difference between the blade length of the longest cutting blade and the blade length of the other cutting blades is 0.60% or more with respect to the reference blade length.