Patent ID: 6206007
Filing Date: 2001-03-27
Classification: A24D

Abstract:
A cigarette with a dual-structure filter, comprising:a dual-structure filter having a first filter element and a second filter element arranged downstream of said first filter element, said first filter element and said second filter element each filter element comprising a cellulose acetate fiber tow;a tobacco rod arranged upstream of said filter; anda tip paper covering a downstream end portion of said tobacco rod and a substantially entire circumferential surface of said filter and having air inflow means comprising at least one row of a plurality of holes formed in a circumferential direction of said filter,wherein an air-permeation resistance per unit length of said first filter element is 1 to 4 mmH.sub.2 O/mm,an air-permeation resistance per unit length of said second filter element is 2 to 7 times an air-permeation resistance per unit length of said first filter element, wherein said air inflow means is formed at an area of said tip paper which corresponds to said first filter element and has an opening position in a range of 4 mm from an upstream end to 14 mm from a downstream end of saidan air inflow ratio from said tip paper is not less than 20%.