It relates to an evaporator device of those which are used to diffuse fragrances, insecticides or other substances which are held in a recipient (1) in the form of two immiscible liquids. It comprises two wicks (2, 2′) which extend from the interior of the recipient (1) in contact with the liquid or the liquids to the exterior where the evaporation area thereof is located, and a stopper cover (3) which closes the recipient (1) and which is traversed by the wicks (2, 2′). One of the wicks (2) has an impermeable layer (4) which extends from its lower extremity to the stopper cover (3) of the recipient (1) preventing contact with one of the liquids and enabling the ingress of the other liquid into the wick (2) only through its lower extremity, thereby allowing the independent egress of each liquid through each wick (2, 2′).