Method for producing polyimide, polyimide, polyimide resin composition, and cured product thereof

A method for producing a polyimide, which comprises a step (1) for obtaining a polyimide by reacting a tetracarboxylic acid and/or a tetracarboxylic acid dianhydride (a) and a diamine (b) in a temperature range of from 80 DEG C to 250 DEG C (inclusive) in a reaction solvent that contains 60-100 mass% of water relative to 100 mass% of the entire reaction solvent, followed by a chain extension step (2) for the obtained polyimide; alternatively, the method for producing a polyimide includes a step (3) for obtaining a polyimide by reacting (d) a tetracarboxylic dianhydride having a purity of 98 mass% or more and (e) a diamine having a purity of 98 mass% or more in a reaction solvent containing 60-100 mass% of water with respect to 100 mass% of the entire reaction solvent in a temperature range of 100-370 DEG C. Provided are: a method for producing a polyimide suitable for use in a surface protective film, an interlayer insulating film or the like of an electronic component, said method being capable of reducing t