Encapsulated flavorant designed for thermal release and cigarette bearing the same

Abstract

Improved delivery of additives is provided through encapsulation. The encapsulated additives can be formed by encapsulating additives using co-ionic cross-linking, in-situ overcoating, and/or step-growth overcoating. By encapsulating additives, additives can be made heat and moisture stable and migration and/or loss of the additives within a cigarette, such as an activated carbon containing cigarette, can be reduced.

What is claimed: 
     
         1 . A smoking article, comprising one or more encapsulated additives in a heating zone of the smoking article wherein the one or more encapsulated additives are heated to at least partially degrade the encapsulant, wherein the one or more encapsulated additives comprise: a flavorant; an encapsulating cross-linked polymer with the flavorant therein, wherein the encapsulated cross-linked polymer forms a polymer-rich outer region and the flavorant forms a flavorant-rich core region; and an overcoating cross-linked polymer layer around the encapsulating cross-linked polymer with the flavorant therein. 
     
     
         2 . The smoking article of  claim 1 , wherein the one or more encapsulated additives comprise about to 5 to 40 wt. % menthol, 40 to 70 wt. % menthol or 70-90 wt. % menthol. 
     
     
         3 . The smoking article of  claim 1 , wherein the encapsulating cross-linked polymer, overcoating cross-linked polymer layer or both comprise two or more polysaccharides. 
     
     
         4 . The smoking article of  claim 3 , wherein the two or more polysaccharides are co-ionically cross-linked in the encapsulating cross-linked polymer, the overcoating cross-linked polymer layer or both. 
     
     
         5 . The smoking article of  claim 1 , wherein the one or more encapsulated additives comprise a spherical capsule with a gel or solid flavorant-rich core region surrounded by a cross-linked polymer-rich outer region within an overcoating cross-linked polymer shell layer. 
     
     
         6 . The smoking article of  claim 1 , wherein the encapsulating cross-linked polymer, the overcoating cross-linked polymer layer or both are effective to thermally release the flavorant upon at least partial thermal degradation of the encapsulating cross-linked polymer and the overcoating cross-linked polymer layer. 
     
     
         7 . The smoking article of  claim 1 , wherein the smoking article comprises a tobacco mat with one or more encapsulated additives thereon, further comprising one or more additional overcoating cross-linked polymer layers on an outer surface of the tobacco mat and the one or more encapsulated additives. 
     
     
         8 . The smoking article of  claim 7 , wherein the one or more additional overcoating cross-linked polymer layers on the outer surface of the tobacco mat comprise at least one of a cross-linked alginate layer, a cross-linked pectin layer, a co-ionically cross-linked alginate-pectin layer or a combination thereof. 
     
     
         9 . The smoking article of  claim 1 , wherein the one or more encapsulated additives are located in a passageway of the smoking article. 
     
     
         10 . The smoking article of  claim 1 , wherein the one or more encapsulated additives are located in a filter of the smoking article. 
     
     
         11 . The smoking article of  claim 1 , wherein the additive in the one or more encapsulated additives is released by exposure to heat and moisture of smoke formed during smoking of the smoking article. 
     
     
         12 . The smoking article of  claim 1 , comprising a cigarette of an electrical smoking system.