Dispensing valve

A subassembly comprising:

• a closure;
• a valve;
• and
• a retaining ring for maintaining said valve within said closure;
• wherein said valve includes
• i) a flexible, resilient head centered on a central axis and extending laterally therefrom, said head having an interior surface to face the interior environment, a concave exterior surface to face the exterior environment, and at least one self-sealing slit through said head,
• ii) confronting, openable portions along the at least one slit to define a normally closed orifice in an unconstrained condition wherein the openable portions can move in a first direction toward the exterior environment to an open orifice configuration and return in an opposite direction to a closed configuration,
• iii) an annular, peripheral attachment portion centered on said central axis and spaced laterally from said head, and
• iv) an annular, flexible, resilient, intermediate portion centered on said central axis and extending laterally from said head to said peripheral attachment portion, said intermediate portion having an interior surface to face said interior environment and an exterior surface to face said exterior environment,
• wherein said interior surface of said head and said interior surface of said intermediate portion intersect at a first circular line of intersection, said exterior surface of said head and said exterior surface of said intermediate portion intersect at a second circular line of intersection, in said closed configuration said first circular line of intersection and said second circular line of intersection are spaced a distance along said central axis no greater than about 0.30 millimeter, and said valve is formed from a thermoplastic elastomer such that said subassembly is recyclable without disassembly.