ABSTRACT OF THE DISCLOSURESMOKE FILTERThis invention provides a smoke filter elementcomprising a filtering core, a smoke impermeable wrapper insurrounding engagement with the core, at least one internalpassage defined between the impermeable wrapper and core andopen at an end of the element, and at least one external passagedefined by the outer surface of the impermeable wrapper andextending to an end of the element; and a cigarette filtercomprising such an element having engaged around said impermeablewrapper tipping material which provides, when the filter isdrawn on in use, for the ingress of external air laterallytherethrough into said external passage(s). The tipping materialmay be a tipping overwrap incorporating the filter in afiltered cigarette. The impermeable wrapper may have longitudinalcorrugations providing the passages, which may extend fully oronly partially the length of the wrapper. The impermeable wrappercan have a circumferential groove communicating with the externalpassage(s), there being air dilution through the tipping materialdirectly into the groove.
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