Smoke filtration
AssigneeBritish-American Tobacco Company Limited
InventorsHenry G. Horsewell, John A. Luke
Life of this patent
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Abstract
A rod-form body of smoke filtration material, preferably fibrous or filamentary, is wrapped in a fibrous or filamentary plugwrap comprising at least 50% by weight of fibres or filaments of thermoplastics material. The plugwrap may have premeability for air of not less than 10,000 Coresta units. The majority, suitably at least 80% by weight, of the material of the rod-form body is a material other than the said themoplastics material of the plugwrap. Thus the smoke-filtration material may comprise crimped polypropylene tow and the plugwrap be composed substantially wholly of fibrous cellulose acetate or conversely. Portions of such filter rod may be subjected to a hot-shaping process to provide grooved filter elements.
Claims10
Smoke filter rod which comprises a rod-form body comprising smoke-filtration material which has been enwrapped in a fibrous or filamentary paper-type plugwrap separate from and non-integral with the body of smoke-filtration material and comprising at least 50% by weight of fibres or filaments of thermoplastics material.
A method of producing smoke-filter rod comprising wrapping a body of smoke-filtration material in a paper-type plugwrap separate from and non-integral with the body of smoke-filtration material and comprising at least 50% by weight of fibres or filaments of thermoplastics material.
Dependencies are inferred from the claim text.