Patent ID: 8602271

Claim:
A device for delivering an aerosol comprising: a valve stem; a diaphragm having walls defining a diaphragm aperture, the diaphragm comprising a first layer in contact with the valve stem with a compression set equal to or greater than 30% and a second layer in contact with the valve stem with a compression set equal to or less than 20%, wherein the compression set is measured according to standard test method ASTM D395-97 under the conditions of 22 hours and 70° C.; and a casing member having walls defining a formulation chamber and a casing aperture, wherein the valve stem passes through the diaphragm aperture and the casing aperture and is in slidable sealing engagement with the diaphragm, and wherein the first layer of the diaphragm having the compression set equal to or greater than 30% is in sealing engagement with the casing member, the device having contained in the formulation chamber thereof a medicinal aerosol formulation.