Stack plate, stack plate device and humidifier

A stack plate of a stack plate device of a humidifier includes inlay parts extending along two opposing front or longitudinal ends of the stack plate, a semipermeable layer disposed on and being stabilized by the inlay parts, and a frame disposed on multiple portions of the semipermeable layer that are disposed on the inlay parts, the frame circumferentially enclosing a through-opening in the stack plate. A remaining portion of the semipermeable layer completely covers the through-opening. An outer circumferential section of the semipermeable layer and the inlay parts are overmolded by the frame. Opposing front ends of the frame define inflow and outflow regions, respectively, on a first side of the frame for a second fluid, and opposing longitudinal ends of the frame define inflow and outflow regions, respectively, on a second side of the frame for a first fluid.