| abstract |
Cigarette filters are prepared by blooming a tow of cellulose acetate fibers, adding or spraying onto the bloomed tow from 1 to 20% by weight (based on the weight of the cellulose acetate fibers) of a plasticizer composed solely of, or comprising as one ingredient, at least one levulinic acid ester, and gathering the thus-treated bloomed tow to form a cigarette filter rod. |