Capsule and plug for a concentrated refill capsule

1. A plug for use in a cap assembly, the plug comprising:

a hollow tubular body with an open proximal end and an open distal end, wherein the open proximal end is surrounded by a first rim that provides a proximal abutment surface for bearing against a frangible sealing component of the cap assembly;

wherein the proximal abutment surface lies in a plane that is orthogonal to a longitudinal axis of the tubular body, and surface surrounds, in total, at least half of the open proximal end;

a skirt extending around the tubular body, and comprising a tubular skirt wall arranged coaxially with respect to the tubular body, the skirt wall being spaced apart from the tubular body in a radial direction to form a plug recess between the skirt wall and the tubular body,

wherein the skirt wall extends from a skirt distal end at which the skirt wall is connected to the tubular body, to a free proximal end,

wherein the free proximal end of the skirt comprises:

an outwardly extending flange comprising a distal facing abutment surface for abutting a rim of a refillable vessel; and

at least one claw radially outwardly of the distal abutment surface.

2. The plug according to claim 1 , wherein the free end of the skirt wall further comprises a proximal sealing rim for sealing against a sealing surface of the cap assembly.

3. The plug according to claim 2 , wherein the proximal sealing rim tapers to a peak.

4. The plug of claim 3 , wherein the sealing peak terminates in the same plane as the first rim.

5. The plug according to claim 1 , wherein the tubular body further comprises at least one cut-out or slot to form a discontinuity in the first rim.

6. The plug of claim 5 , wherein the tubular body further comprises diametrically opposed cut outs.

7. The plug according to claim 1 , wherein the tubular body comprises a protrusion or ridge extending around an outer surface of the tubular body.

8. The plug according to claim 1 , wherein the at least one claw curves away from the distal abutment surface to provide a distal concave surface and a proximal convex surface.

9. A cap system, the cap system comprising:

the plug of claim 1 ; and

a cap assembly comprising:

an inner wall defining a conduit through the cap assembly, the conduit extending from an upstream end to a downstream end;

an outer wall surrounding the inner wall along at least a first portion of its length, wherein the outer wall is spaced from the first portion of the inner wall to define a circumferential void between the inner and outer walls extending from an open downstream end to a closed upstream end;

a connecting wall extending between the inner and outer walls to prevent fluid flow through the void, the connecting wall forming the closed upstream end of the void;

wherein the cap assembly further comprises a closure member configured to seal the conduit, the closure member comprising an upstream side and a downstream side,

wherein the closure member is sealed to the inner wall with a peripheral frangible connection located between proximal and distal ends of the conduit,

wherein the frangible connection extends in a plane P, which is orthogonal to a longitudinal axis (A) of the conduit; and

wherein the plug is disposed within the cap assembly such that the outer wall of the cap assembly surrounds the plug, and the inner wall of the cap assembly extends into the plug recess, and

wherein the proximal abutment surface of the plug is aligned with and opposes a bearing surface of the closure member.

10. The system according to claim 9 , wherein the frangible connection is disposed between a first peripheral recess formed between the inner wall and a downstream side of the closure member, and a second peripheral recess between the inner wall and an upstream side of the closure member.

11. The system according to claim 9 , wherein the bearing surface extends in a plane that is perpendicular to the longitudinal axis (A) of the conduit.

12. The system according to claim 9 , wherein the closure member is conical or frustoconical, and extends from a base to a peak.

13. The system according to claim 9 , wherein the outer wall comprises engagement means, and wherein the at least one claw is configured to engage the engagement means.

14. The system according to claim 9 , wherein the inner wall comprises a protrusion or ridge extending radially inwardly from an inner surface of the inner wall.

15. A refill system comprising the system according to claim 9 , wherein the refill system further comprises a capsule for containing a concentrated cleaning product, wherein the capsule is engaged with the cap assembly and wherein an internal volume of the capsule is in fluid communication with an upstream end of the conduit.

16. The refill system according to claim 15 , wherein the capsule comprises an opening surrounded by a rim, and wherein the rim bears against the connecting wall of the cap assembly.

17. The plug of claim 1 , wherein the proximal abutment surface has at least two fold rotational symmetry about the longitudinal axis.