EP0631770B1 — New use of polymeric membranes in the dispensing of pharmaceutical solutions that contain quaternary ammonium compounds as preservatives and corresponding dose dispensor

USPTO Abstract

Said use is characterized in that the cited membranes are placed adequately in the dropper of the dose dispensor and are used to achieve the selective flow of essentially all the active product and the selective retention of essentially all the preservative during pharmacological treatment. The membrane (5) is coupled between the cylinder units (6 and 7) of parts (3 and 4) of the dropper, remaining in a movable position (Figure 3) thanks to the existence of a certain play between said cylinder units; or else, in a fixed position (Figure 4) due to the lack of said play; or else, in a fixed position but with the membrane treated adequately, so that it has a small area or "stain" that permits the flow of air; (8) represents the outlet duct. <IMAGE> <IMAGE>