abstract:A screw cap is a metal cap that screws onto threads on the neck of a bottle, generally with a metal skirt down the neck to resemble the traditional wine capsule ("foil"). A layer of plastic (often PVDC), cork, rubber, or other soft material is used as wad to make a seal with the mouth of the bottle.
Ten years ago, as wineries began to seal bottles with screwcaps instead of corks, there was an initial backlash before a long, slow period of acceptance that, some would argue, remains ongoing.
But few of today's imaginative ideas would have made it onto drawing boards without cork's competition from screw-top bottle caps, plastic stoppers and aluminum Tetra Paks.