Composite Wick

Abstract

A wick having a predominant material and a secondary material, for use in a vaping environment, makes use of characteristics of each of these materials to provide reliable wicking and a desired heat transfer characteristic. Many materials known to have good wicking characteristics act as insulators, which can result in a buildup of heat in the wick near a heater. This buildup of heat can result in the burning of one or both of the wick and the e-liquid carried by the wick. The inclusion of a secondary material having improved heat transfer characteristics allows for the wick to transport heat through at least one of the length and depth of the wick. In one embodiment, a cotton wick is supplemented by the addition of metal strands making up approximately 25% of the wick by volume.

1 . A wick, for drawing an atomizable liquid from a reservoir towards a heater, the wick comprising:
 a predominant material comprising at least one of a natural fibrous material and a synthetic fibrous material; and   a secondary material comprising at least one of : a metal, graphite, carbon fiber, a doped silicon and a carbonized filament.   
     
     
         2 . The pod of  claim 1  wherein the atomizable liquid is an e-liquid comprising at least one of propylene glycol, vegetable glycerin, nicotine and a flavoring. 
     
     
         3 . The wick of  claim 1  wherein the metal is one of aluminium, copper, silver, and stainless steel. 
     
     
         4 . The wick of  claim 1  wherein the natural fibrous material comprises at least one of: cotton, hemp, linen, wool, rayon, silk, cellulose and wood fiber 
     
     
         5 . The wick of  claim 1  wherein the synthetic fibrous material comprises at least one of a polyester and a glass fiber. 
     
     
         6 . The wick of  claim 1  wherein the predominant material is a combination of two or more materials. 
     
     
         7 . The wick of  claim 1  wherein the predominant material is an insulator. 
     
     
         8 . The wick of  claim 1  wherein the secondary material has higher heat transfer capacity than the predominant material. 
     
     
         9 . The wick of  claim 1  wherein the predominant material has higher wicking capacity with respect to the atomizable liquid than the secondary material. 
     
     
         10 . The wick of  claim 1  wherein the predominant material is cotton and the secondary material is a metal. 
     
     
         11 . The wick of  claim 10  wherein the secondary material makes up between 20% and 30% of the wick by volume. 
     
     
         12 . The wick of  claim 1  wherein the predominant material is cotton and the secondary material is carbon fiber. 
     
     
         13 . The wick of  claim 12  wherein the secondary material makes up between 45% and 55% of the wick by volume. 
     
     
         14 . The wick of  claim 1  further comprising a heater coil wrapped around the first and second materials, the heater coil comprised of a metal and the heater coil and the secondary material are different materials. 
     
     
         15 . A wick, for drawing an atomizable liquid from a reservoir towards a heater, the wick comprising:
 a predominant material having a permeability coefficient of approximately 2.25×10 −13  m 2  ; and   a secondary material having thermal conductivity of at least approximately 100 W/m K.   
     
     
         16 . The wick of  claim 15  wherein the atomizable liquid is an e-liquid comprising at least one of propylene glycol, vegetable glycerin, nicotine and a flavoring. 
     
     
         17 . The wick of  claim 15  wherein the predominant material comprises at least one of: cotton, hemp, linen, wool, rayon, polyester, glass fiber, cellulose and wood fiber. 
     
     
         18 . The wick of  claim 15  wherein the secondary material comprises at least one of: a metal, graphite, carbon fiber, a doped silicon and a carbonized filament. 
     
     
         19 . The wick of  claim 15  wherein the predominant material is cotton and the secondary material is a metal making up between 20% and 30% of the wick by volume. 
     
     
         20 . The wick of  claim 15  wherein the predominant material is cotton and the secondary material is carbon fiber making up between 45% and 55% of the wick by volume.