Self-extinguishing cigarettes

Abstract

This invention concerns the use of specific coatings that are applied to the paper wrapper that encloses the cigarette's smoking medium for limiting in a predictable manner the free burning time of the treated cigarette, or controlling the lapsed time prior to self-extinguishment after being lit and left unattended. The coating materials are generally identified as hydrophylic colloids or aqueous-soluble polymers, that are deposited singly or as mixtures from aqueous media, and are represented by locust bean gum, pectin, sodium carboxymethylcellulose, and guar gum, forming adherent, non-tacky, flexible coatings on the paper housing substrates, and significantly altering the burning characteristic of the resultant cigarettes. Comparable behaviors are obtained, for equivalent weight percentages of the deposited solids, by either precoating the portion of paper wrapper that subsequently encloses the charge of tobacco or by post-treatment of the external surface of the assembled cigarette. For cigarettes having paper wrapper coated to contain 20.+-.10 weight percent solids of this invention, based on the weight of the treated paper that encloses the smoking medium, after being lit and left unattended a self-extinguishing time of approximately 11/2 to 3 minutes can be expected, meeting a practicable compromise for the smoker between safety and smoking convenience.

Dependencies are inferred from the claim text.