| 摘要 |
A filter cigarette producing method includes a core forming fiber processing step of adding a plasticizer to core forming fibers (4) having a total fineness of 23000 denier to 70000 denier so as to attain an additive rate of 13% to 40%; a sheath forming fiber processing step of adding a plasticizer to sheath forming fibers (5) having a total fineness of 10000 denier to 47000 denier so as to attain an additive rate of 15% or less, or adding no plasticizer to the sheath forming fibers so as to attain an additive rate of 0%; a hollow filter forming step of forming a hollow filter (11) subsequent to the core forming fiber processing step and the sheath forming fiber processing step in such a manner that the core forming fibers (4) are hardened into a core (11a) including a hole (10) extending from one end surface toward the other end surface, and an outside of the core (11a) is covered with the sheath forming fibers (5) so as to form a sheath (11b), thereby forming the hollow filter (11); and a post-treatment step of conveying the hollow filter (11) through a narrower section that is smaller than a diameter of the hollow filter (11), and greater than a diameter of the core (11a) subsequent to the hollow filter forming step. |
