CIGARETTE FILTER

摘要

UNITED STATES PATENT APPLICATION of ROBERT A. SANFORD and ROBERT R. JOHNSON for IMPROVED CIGARETTE FILTER A filter for a cigarette includes a porous filter rod circumscribed by a smoke impervious wrapper wherein the filter rod with the smoke impervious wrapper therearound is provided with grooves embedded therein and extending from one end thereof a preselected distance longitudinally therealong. Tipping material circumscribes the smoke impervious wrapper and is provided with flow-through openings therein in flow communication with the grooves. Support means are provided for the tipping material at the mouth end of the filter to maintain the tipping material in circumferential equalization.