Electronic smoking article

Abstract

An electronic smoking article includes a reservoir including a liquid aerosol formulation, a heater operable to at least partially volatilize the liquid aerosol formulation and form an aerosol, and a filter segment formed of polylactic acid fibers or a crimped polylactic acid film. The filter segment includes at least one additive and is positioned downstream of the heater.

We claim: 
     
         1 . An electronic smoking article operable to produce an aerosol comprising:
 a liquid aerosol formulation;   a heater operable to at least partially volatilize the liquid aerosol formulation and form an aerosol; and   a filter segment formed of polylactic acid fibers or a crimped polylactic acid film, the filter segment including at least one additive and being positioned downstream of the heater and operable to elute the at least one additive into the aerosol as the aerosol passes through the filter segment.   
     
     
         2 . The electronic smoking article of  claim 1 , wherein the filter segment has a length ranging from about 2 mm to about 30 mm and an outer diameter that is about the same or less than an inner diameter of an outer housing of the electronic smoking article. 
     
     
         3 . The electronic smoking article of  claim 1 , wherein the polylactic acid fibers are substantially parallel. 
     
     
         4 . The electronic smoking article of  claim 1 , wherein the filter segment is detachable and a sleeve is operable to attach the filter segment to the electronic smoking article. 
     
     
         5 . The electronic smoking article of  claim 1 , further including a mouth end insert positioned downstream of the filter segment. 
     
     
         6 . The electronic smoking article of  claim 1 , further including a mouth end insert positioned upstream of the filter segment. 
     
     
         7 . The electronic smoking article of  claim 1 , wherein the at least one additive is selected from the group consisting of flavors, aerosol modifiers, aromatic materials, pH modifying agents, chemesthesis agents, volatile acids and combinations thereof. 
     
     
         8 . The electronic smoking article of  claim 1 , wherein the at least one additive is impregnated in the filter segment or included in a coating on at least one surface of the filter segment. 
     
     
         9 . The electronic smoking article of  claim 1 , wherein the at least one additive is encapsulated or microencapsulated. 
     
     
         10 . The electronic smoking article of  claim 1 , wherein the heater comprises a capillary in fluid communication with a reservoir. 
     
     
         11 . The electronic smoking article of  claim 10 , wherein the reservoir is pressurized and includes a mechanically or electrically operated valve at an outlet of the reservoir. 
     
     
         12 . The electronic smoking article of  claim 10 , wherein the reservoir is compressible such that the liquid material is manually pumped to the capillary. 
     
     
         13 . The electronic smoking article of  claim 1 , wherein the heater is a coil heater in communication with a filamentary wick which draws the liquid aerosol formulation from a reservoir via capillary action. 
     
     
         14 . The electronic smoking article of  claim 13 , wherein the electronic smoking article further comprises:
 an outer tube extending in the longitudinal direction;   an inner tube within the outer tube; and   the reservoir comprising the liquid aerosol formulation contained in an outer annulus between the outer tube and the inner tube,   wherein the coil heater is located in the inner tube and the filamentary wick is in communication with the reservoir and surrounded by the coil heater such that the filamentary wick delivers the liquid aerosol formulation to the coil heater and the coil heater heats the liquid aerosol formulation to a temperature sufficient to vaporize the liquid aerosol formulation and form an aerosol.   
     
     
         15 . The electronic smoking article of  claim 14 , wherein the electronic smoking article comprises a first section attachable to a second section and wherein the filamentary wick, the reservoir and filter segment are contained in the first section and a power supply operable to apply voltage across the heater is contained in the second section. 
     
     
         16 . The electronic smoking article of  claim 1 , wherein the at least one additive is dispersed substantially uniformly throughout the filter segment. 
     
     
         17 . The electronic smoking article of  claim 1 , wherein a concentration of the at least one additive varies along a length of the filter segment. 
     
     
         18 . The electronic smoking article of  claim 7 , wherein the volatile acid is pyruvic acid. 
     
     
         19 . The electronic smoking article of  claim 7 , wherein the volatile acid is operable to reduce a pH of the aerosol to a pH ranging from about 4 to about 8.