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US 4,615,345 AGranted
Wrapper constructions for self-extinguishing smoking articles
AssigneeKimberly-Clark Corporation
InventorDonald F. Durocher
Life of this patent
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AssigneeKimberly-Clark Corporation
InventorDonald F. Durocher
Estimating the term…
The invention is an improved specially designed wrapper construction for smoking articles producing controlled burn properties of smoking articles such as cigarettes so that the cigarette will self-extinguish after free burning in air for a designed time period. In addition, the wrapper construction results in cigarettes with reduced tendency to ignite combustible substrates, such as upholstered furniture, when in contact with them. Therefore, smoking articles with this wrapper construction reduce the likelihood of accidental fires, yet they free-burn rapidly for a designed period of time without puffing. However, during a normal puffing sequence the behavior of cigarettes with these wrappers is indistinguishable from commercial cigarettes. On the other hand, other self-extinguishing cigarettes go out without puffing and therefore have to be relighted frequently. The wrapper constructions of the present invention include single or double wraps of cigarette paper which are inherently incapable without elevated levels of burn promoting chemical or supporting cigarette free burn. The construction is modified by application of a plurality of zones of elevated levels of burn promoter to the extent that the cigarette burns normally in the treated zones. Thus, when the burning coal advances to an area of untreated wrap, it reliably self-extinguishes unless puffed. The extent of the treated zones controls the time required for the cigarette to self-extinguish. Required wrappers are preferably those having a Burn Mode Index ("BMI") as defined in the range of from about 1.5 cm.sup.-1 to about 6.0 cm.sup.-1 for the single wrap embodiment and, for the double wrap embodiment, about 0.1 cm.sup.-1 to about 4.0 cm.sup.-1 for the inner wrap and about 2 cm.sup.-1 to about 40 cm.sup.-1 for the outer wrap depending on the BMI of the inner wrap. The wrappers and smoking articles of the invention may be produced using conventional methods and equipment.
A single wrapper construction for a smoking article, said wrapper construction comprising a base web containing cellulose fibers, said base web being nonburning under normal smoking conditions, said base web containing a plurality of zones treated with a burn promoter in sufficient amount to cause said wrapper construction in use to maintain burn of said smoking article within said zones but said wrapper construction causing said smoking article to self-extinguish outside of said zones if not puffed.
A double wrapper construction for a smoking article, said wrapper construction comprising an inner base web that contains cellulose fibers and is nonburning under normal smoking conditions and an outer base web, said combination of inner base web and outer base web containing a plurality of zones treated with a burn promoter in sufficient amount to cause said wrapper construction in use to maintain burn of said smoking article within said zones but said wrapper construction causing said smoking article to self-extinguish outside of said zones if not puffed.
A smoking article comprising a tobacco column and a single wrapper construction, said wrapper construction comprising a base web containing cellulose fibers, said base web being nonburning under normal smoking conditions, said base web containing a plurality of zones treated with a burn promoter in sufficient amount to cause said wrapper construction in use to maintain burn of said smoking article within said zones but said wrapper construction causing said smoking article to self-extinguish outside of said zones if not puffed.
A smoking article comprising a tobacco column and a double wrapper construction, said wrapper construction comprising an inner base web that contains cellulose fibers and is nonburning under normal smoking conditions and an outer base web, said combination of inner base web and outer base web containing a plurality of zones treated with a burn promoter in sufficient amount to cause said wrapper construction in use to maintain burn of said smoking article within said zones but said wrapper construction causing said smoking article to self-extinguish outside of said zones if not puffed.
Dependencies are inferred from the claim text.