Sealing cap having a push-button for emptying a capsule formed thereby

A fillable sealing cap (1), screwable or attachable to a threaded connector of a container, having a push button (2) for triggering the emptying of a capsule (4) being formed under said push button (2) and being open at the bottom and sealable with a sealing washer (3), said capsule (4) having a circumferential capsule wall (5) and capsule lid (6), for receiving a substance which can be emptied into a container equipped with this sealing cap (1), wherein, on the outside of the capsule lid (6), a central push button (2) is formed for pressing down the capsule lid (6) while deforming it, characterised in that a central, axially downwardly projecting stamp (7) is formed on the inside of the capsule (18) below the push button (2), and that at least two spreading legs (8), which can be pivoted downwards and outwards to the closure axis of rotation (21), are formed around the circumference of this stamp (7), which taper off via their end region into an elastically bendable tapering as feet (26), further that the capsule lid (6) is designed to be corrugated around the stamp (7) when viewed in the radial direction, wherein this capsule lid (6) is designed in the first, inner corrugated area (10) of its radius with a thinner wall thickness than in the second, outer corrugated area (11), such that the lid wall can be flexed in two phases by pressing the push button (2) from above, in that the inner lid region (10) is first flexable by axially depressing the push button (2), until the stamp (7) applies pressure to the sealing washer (3) at pressure points (23) and thereby pretensions said sealing washer and the spreading legs (8) touch the sealing washer (3), thereafter the outer corrugated area (11) can be flexed by further depressing the push button (2) and thus the end regions of the spreading legs (8), while the stamp (7) breaks through the sealing washer (3), pivot the resulting loose sealing washer segments downwards so that the opening of the capsule (4) is exposed.