Separation functional layer, separation membrane, and method for manufacturing separation functional layer

A separation functional layer comprising:

• an ionic liquid;
• a polymer A that is a fluorine-based polymer;
• and
• a polymer B different from the polymer A.

A method for manufacturing a separation functional layer including an ionic liquid, a polymer A that forms a crystal structure in the ionic liquid, and a polymer B different from the polymer A, the method comprising

• at least one selected from the group consisting of step (i) and step (ii) below.
• Step (i):
• allowing, in a mixed solution M1 containing the ionic liquid, the polymer A, a prepolymer, and a crosslinking agent, the prepolymer to react with the crosslinking agent in such a manner that the polymer B is formed.
• Step (ii):
• drying a mixed solution M2 containing the ionic liquid, the polymer A, and the polymer B.