Tobacco smoke filter
AssigneeEastman Chemical Company
InventorsBobby M. Phillips, Steven A. Wilson, Mark A. Pollock
Life of this patent
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Abstract
Disclosed are articles, such as smoke filters, which contain fibers that have complex geometry in combination with tobacco smoke modifying agents such as flavorants. The fibers are preferably made of a polyester such as poly(ethylene terephthalate) and preferably are capable of spontaneously transporting water or n-decane on their surfaces. The articles of the invention result in improved delivery of the tobacco smoke modifying agent to the user.
Claims16
A filter comprising a generally cylindrical inner member, an outer member generally concentrically surrounding said inner member and a plugwrap generally concentrically surrounding said outer member, either said inner member or said outer member being a filter element of tow having filaments extending in an axial direction with respect to said filter, and the other of said inner member or outer member comprising at least one fiber having at least one continuous groove which is capable of spontaneously transporting water on the surface thereof wherein said fiber satisfies the equation
- (1-X cos .theta..sub.a)<0,
- wherein
- .theta..sub.a is the advancing contact angle of water measured on a flat film made from the same material as the fiber and having the same surface treatment, if any,
- X is a shape factor of the fiber cross-section that satisfies the following equation ##EQU7## wherein P.sub.w is the wetted perimeter of the fiber and r is the radius of the circumscribed circle circumscribing the fiber cross-section and D is the minor axis dimension across the fiber cross-section,
- and at least one tobacco smoke modifying agent in combination with said fiber.
A filter comprising a generally cylindrical inner member, an outer member generally concentrically surrounding said inner member and a plugwrap generally concentrically surrounding said outer member, said inner member being a filter element of tow having filaments extending in an axial direction with respect to said filter, and said outer member comprising at least one fiber having at least one continuous groove which is capable of spontaneously transporting water on the surface thereof wherein said fiber satisfies the equation
- (1-X cos .theta..sub.a)<0,
- wherein
- .theta..sub.a is the advancing contact angle of water measured on a flat film made from the same material as the fiber and having the same surface treatment, if any,
- X is a shape factor of the fiber cross-section that satisfies the following equation ##EQU8## wherein P.sub.w is the wetted perimeter of the fiber and r is the radius of the circumscribed circle circumscribing the fiber cross-section and D is the minor axis dimension across the fiber cross-section,
- and at least one tobacco smoke modifying agent in combination with said fiber.
Dependencies are inferred from the claim text.