Abstract:
A light-lock cap comprising a shell, means to seal said shell to a container, means to allow passage of fluids through said cap into a container covered by said cap, means to allow gases to exit a container covered by said cap, said means for liquid passage comprises a labyrinth passage with an upward facing inlet and downward facing exit, said means for gases to exit comprises a labyrinth passage with a side facing orifice on the interior of said cap and a side facing orifice on the exterior of said cap. There is also provided a method of forming the cap.