Degradable filter element for smoking article

Abstract

A filter material configured for use as a filter element of a smoking article is provided, the filter material including at least one segment of fibrous tow having a plurality of superabsorbent objects dispersed therein, the superabsorbent objects comprising a starch material. Exemplary starch materials include naturally-occurring starch, hydroxyalkylated starch, starch esters, ionically modified starch, oxidized starch, hydrolyzed starch, plasticized starch, gelatinized starch, grafted starch, crosslinked starch, transglycosylated starch, starch ethers, and mixtures thereof, as well as blends of starch with other polymers. Filter elements and smoking articles, such as cigarettes, that contain the filter material are also provided. A method of preparing polymer fibers for use in filter elements is also provided, the method including adding the starch material to a fiber precursor solution prior to fiber extrusion or dry-blending the starch material with the polymer material to be formed into fibers.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a non-provisional application which claims priority to U.S. provisional application Ser. No. 61 / 360,201, filed Jun. 30, 2010, which is incorporated by reference herein in its entirety.TECHNICAL FIELD[0002]The present invention relates to products made or derived from tobacco, or that otherwise incorporate tobacco, and are intended for human consumption, and in particular, to filters for cigarettes. The invention is directed to additives for filter elements configured for increasing the rate of degradation.BACKGROUND[0003]Popular smoking articles, such as cigarettes, have a substantially cylindrical rod-shaped structure and include a charge, roll or column of smokable material, such as shredded tobacco (e.g., in cut filler form), surrounded by a paper wrapper, thereby forming a so-called “smokable rod” or “tobacco rod.” Normally, a cigarette has a cylindrical filter element aligned in an end-to-end relationship with the...

AI Technical Summary

Benefits of technology

[0007]Embodiments of the present invention relate to a smoking article and associated methods, and in particular, a rod-shaped smoking article (e.g., a cigarette). The smoking article includes a lighting end (i.e., an upstream end) and a mouth end (i.e., a downstream end). A mouth end piece is located at the extreme mouth end of the smoking article, and the mouth end piece allows the smoking article to be placed in the mouth of the smoker to be drawn upon. The mouth end piece has the form of a filter element comprising a fibrous tow filter material. The fibrous tow filter material may incorporate an effective amount of a degradable starch material (or other degradable polymer material) configured for increasing the rate of degradation of the filter material upon disposal. Dispersal of a degradable material throughout the fibrous tow can enhance degradation by creating voids within the fibrous tow as the degradable material decomposes, thus increasing available surface area within the fibrous tow for contact with the environment.

Problems solved by technology

Cigarette filters are slow to degrade or disperse in the environment.

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