Martin W Henley, 805 Stillwater Ct, Murrells Inlet, SC 29576

5219101, Jun 15, 1993

Jan 17, 1991

7/642158

Vlado I. Matkovich - Glen Cove NY
Thomas E. Schlaudecker - Hamilton Square NJ
Martin W. Henley - New Hope PA
Thomas Bormann - Seaford NY

Pall Corporation - Glen Cove NY
Merck & Co., Inc. - Rahway NJ

B67D 558

222189

A device for dispensing liquids in drop form of substantially uniform size is provided which includes a container having a dropper tip including a passageway for ingress of air to and egress of liquid from the device, the passageway communicating between the container and an orifice in the dropper tip; means for temporarily reducing the volume of the container; and, disposed within the dropper tip, across the passageway, a microporous composite membrane with pores of a size to resist passage of contaminants. The membrane has a liquophilic component which permits delivery of drops of a liquid to a desired location outside the container and a liquophobic component which is adapted to resist the passage of such liquid but to permit the passage therethrough of air. Both the liquophilic and liquophobic components of the membrane (which intersects the passageway) communicate with the passageway. The surface area and pore size of the liquophilic component is so selected as to meter liquid being dispensed in drop form and avoid a stream of liquid from emerging from the dropper tip during normal use.