The joint-sealing tape of flexible foam capable of recovering its shape after compression with two lateral surfaces (3, 4) is colored on at least one of the two lateral surfaces (3, 4) with a colorant in such a way that, in a partially expanded functional state of the sealing tape, i.e., in a state of partial recovery after compression, the coloring on the lateral surface (3, 4), when viewed from the side, appears to the human eye as a continuous colored surface.