Polyimide, resin film, and metal-clad laminate

A polyimide obtained by reacting an anhydride component comprising an aromatic tetracarboxylic anhydride with a diamine component comprising an aromatic diamine, wherein

• the anhydride component contains, relative to the whole anhydride component, 40 mol % or more of an aromatic tetracarboxylic anhydride selected from the group consisting of pyromellitic dianhydride and 1,4,5,8-naphthalenetetracarboxylic dianhydride,
• the diamine component contains, relative to the whole diamine component, 40 to 99 mol % of an aromatic diamine represented by the following general formula:
• in which R11 and R12 independently represent a hydrogen atom, or an alkyl group optionally substituted with a halogen atom or phenyl, at least two of R11 and R12 represent alkyl groups optionally substituted with a halogen atom or phenyl, and n2 represents an integer of 1 to 4,
• and contains, relative to the whole diamine component, 1 to 4 mol % of a dimer acid-type diamine produced by replacing each of two terminal carboxyl groups in a dimer acid with a primary aminomethyl or amino group.