| 摘要 |
PROBLEM TO BE SOLVED: To provide a film which, in the form of a magnetic recording medium, has good electromagnetic conversion characteristics and durability. SOLUTION: This aromatic polyamide film comprises an arom. polyamide and at least one different kind of polymer, wherein the content of the polymer is 10 to 40 wt.% based on the arom. polyamide, the solubility parameterδa of the arom. polyamide and the solubility parameterδb of the dissimilar polymer meet the equation: 50 (MJ/m<3> )<1/2> <=δa<=70 (MJ/m<3> )<1/2>|δa-δb|<=15 (MJ/m<3> )<1/2> , and, on at least one side of the film, the number of protrusions having a height of not less than 5 nm is 3×10<5> to 50×10<5> /mm<2> , the number of protrusions having a height of not less than 50 nm is not more than 25×10<4> /mm<2> , and the sectional area of protrusions cut on a horizontal plane at a height of 5 nm is 5 to 40% of the measured area. |
