A package has a "push-pull" type dispensing closure either threadably engaged with or in press-fit engagement with the container mouth. The closure includes an outer skirt that is pliable and inwardly deformable when squeezed and a dispenser plug member selectively positionable to seal or unseal...http://www.google.es/patents/US5850951?utm_source=gb-gplus-sharePatente US5850951 - Package with push-pull dispensing closure
