Smoking Articles And Filter Therefor

Abstract

A filter for smoking articles includes two sections, a first section ( 2 ) comprising a longitudinally extending opening ( 4 ) surrounded by smoke impervious material ( 6 ) and a second section ( 8 ) comprising a core ( 10 ) having a high-pressure drop material, a circumscribing annulus ( 12 ) having a lower pressure drop filter material than the core. The first section ( 2 ) is generally adjacent to the tobacco section ( 18 ) of a cigarette ( 3 ) at a first end and is spaced from the second section ( 8 ). Moreover, the invention comprises ventilation holes ( 20 ) circumscribing the space or gap ( 14 ) between the first and second section or circumscribes the second section ( 8 ).

1 . A filter for smoking articles comprising:
 a first section comprising smoke impervious material having a longitudinally extending smoke flow path therethrough;   a second section spaced from and axially aligned with said first section, said second section comprising a core portion circumscribed by an annulus portion;   wherein one of said core portion and annulus portion comprises high pressure drop filter material and the other portion comprises lower pressure drop material;   wherein said smoke flow path is longitudinally aligned with said annulus or core portion that comprises high pressure drop material.   
   
   
       2 . The filter for smoking articles of  claim 1 , wherein said smoke flow path is an opening centrally disposed in said first section. 
   
   
       3 . The filter for smoking articles of  claim 2 , wherein said smoke flow path includes a tube therein. 
   
   
       4 . The filter for smoking articles of  claim 1 , wherein said smoke flow path comprises lower pressure drop material than said smoke impervious material. 
   
   
       5 . The filter for smoking articles of  claim 4 , wherein said lower pressure drop material is centrally disposed in said first section. 
   
   
       6 . The filter for smoking articles of  claim 4 , wherein said lower pressure drop material circumscribes said smoke impervious material in an annulus/core relationship. 
   
   
       7 . The filter for smoking articles of  claim 2  further comprising ventilation holes. 
   
   
       8 . The filter for smoking articles of  claim 7 , wherein said ventilation holes circumscribe said second section. 
   
   
       9 . The filter for smoking articles of  claim 7 , wherein said ventilation holes are located between said first section and said second section. 
   
   
       10 . The filter for smoking articles of  claim 7 , wherein said ventilation holes allow outside air to enter said filter. 
   
   
       11 . The filter for smoking articles of  claim 10 , wherein the amount of air pulled through said ventilation holes increases as said tube fills with tar. 
   
   
       12 . The filter for smoking articles of  claim 1 , wherein said smoke flow path is between 5 and 10 mm in length. 
   
   
       13 . The filter for smoking articles of  claim 1 , wherein said smoke flow path is between 0.5 and 3 mm in diameter. 
   
   
       14 . The filter for smoking articles of  claim 1 , wherein the diameter of said core of said second section is approximately 60% of the diameter of said filter. 
   
   
       15 . The filter for smoking articles of  claim 1 , wherein there is less than 4 mm between said first section and said second section. 
   
   
       16 . A smoking article comprising
 a rod of smokable material;   a wrapper circumscribing said rod of smokable material; and   a filter comprising a first section and a second section;   said first section having a first end and an opposed end, said first end being attached to said rod of smokable material, said first section comprising smoke impervious material having a centrally disposed longitudinally extending opening therethrough; and   said second section spaced from and axially aligned with said opposed end of said first section, said second section comprising a core portion comprising high pressure drop filter material circumscribed by an annulus portion comprising a lower pressure drop filter material than said core portion.   
   
   
       17 . The smoking article of  claim 16 , wherein said opening includes a tube therein. 
   
   
       18 . The smoking article of  claim 17  further comprising ventilation holes. 
   
   
       19 . The smoking article of  claim 18 , wherein said ventilation holes circumscribe said second section. 
   
   
       20 . The smoking article of  claim 18 , wherein said ventilation holes are located between said first section and said second section. 
   
   
       21 . The smoking article of  claim 18 , wherein said ventilation holes allow outside air to enter the filter. 
   
   
       22 . The smoking article of  claim 21 , wherein the amount of air pulled through said ventilation holes increases as said tube fills with tar. 
   
   
       23 . The smoking article of  claim 16 , wherein said opening is between 5 and 10 mm in length. 
   
   
       24 . The smoking article of  claim 16 , wherein said opening is between 0.5 and 3 mm in diameter. 
   
   
       25 . The smoking article of  claim 16 , wherein the diameter of said core of said second section is approximately 60% of the diameter of said filter. 
   
   
       26 . The smoking article of  claim 16 , wherein there is less than 4 mm between said first section and said second section. 
   
   
       27 . A filter for smoking articles comprising:
 a first section comprising smoke impervious material having a longitudinally extending smoke flow path therethrough;   a second section spaced from and axially aligned with said first section, wherein said second section comprises a mouth end and a gap end;   a smoke impervious blocking patch attached to the gap end of said second section;   wherein said smoke flow path is longitudinally aligned with said blocking patch.   
   
   
       28 . The filter for smoking articles of  claim 27 , wherein said smoke flow path is an opening centrally disposed in said first section. 
   
   
       29 . The filter for smoking articles of  claim 28 , wherein said smoke flow path includes a tube therein. 
   
   
       30 . The filter for smoking articles of  claim 27 , wherein said smoke flow path comprises lower pressure drop material than said smoke impervious material. 
   
   
       31 . The filter for smoking articles of  claim 30 , wherein said lower pressure drop material is centrally disposed in said first section. 
   
   
       32 . The filter for smoking articles of  claim 30 , wherein said lower pressure drop material circumscribes said smoke impervious material in an annulus/core relationship. 
   
   
       33 . The filter for smoking articles of  claim 28  further comprising ventilation holes. 
   
   
       34 . The filter for smoking articles of  claim 33 , wherein said ventilation holes circumscribe said second section. 
   
   
       35 . The filter for smoking articles of  claim 33 , wherein said ventilation holes are located between said first section and said second section. 
   
   
       36 . The filter for smoking articles of  claim 33 , wherein said ventilation holes allow outside air to enter the filter. 
   
   
       37 . The filter for smoking articles of  claim 36 , wherein the amount of air pulled through said ventilation holes increases as said tube fills with tar. 
   
   
       38 . The filter for smoking articles of  claim 27 , wherein said smoke flow path is between 5 and 10 mm in length. 
   
   
       39 . The filter for smoking articles of  claim 27 , wherein said smoke flow path is between 0.5 and 3 mm in diameter. 
   
   
       40 . The filter for smoking articles of  claim 27 , wherein there is less than 4 mm between said first section and said second section. 
   
   
       41 . A filter for smoking articles substantially as hereinbefore described with reference to the accompanying drawings. 
   
   
       42 . A smoking article substantially as hereinbefore described with reference to the accompanying drawings.