Foam dispenser for foamable solutions

A foam dispenser, comprising:

• a plastic bottle made of flexible plastic having a bottle opening;
• a closure cap which seals the bottle opening and has a dispensing opening for a foam;
• a foam-generating device for foaming a solution comprising a chamber having at least one wall, at least one inlet for air in a wall of the chamber, and at least one inlet for liquid in a wall of the chamber, and at least one porous body which is arranged in the chamber, the foam-generating device being arranged in or connected to the closure cap, and
• a riser pipe which is arranged inside the plastic bottle and is connected to an inlet,
• wherein the at least one porous body consists of an open-cell foam material and the open-cell foam material has a density of more than 0.03 g/cm3.