Air freshening device

Abstract

An air freshening device includes a liquid supply operable to supply liquid fragrance material, a wick in contact with the liquid supply, a conductive mesh material operable to retain the liquid material in interstices thereof, and a power supply operable to apply voltage across the mesh material so as to heat the mesh material and the liquid fragrance material contained in interstices of the mesh material to a temperature sufficient to vaporize the liquid. The air freshening device is operable to substantially prevent deposition of the vaporized liquid material.

We claim: 
     
         1 . An air freshening device comprising:
 a liquid supply;   a wick in contact with liquid in the liquid supply;   a flat layer of conductive mesh material operable to retain the liquid in interstices thereof; and   a power supply operable to apply voltage across a heater comprising the conductive mesh material so as to heat the liquid contained in interstices of the mesh material to a temperature sufficient to vaporize the liquid.   
     
     
         2 . The air freshening device of  claim 1 , wherein the conductive mesh material comprises at least one material selected from the group consisting of stainless steel, copper, copper alloys, porous ceramic materials coated with film resistive material, nickel-chromium alloys, and combinations thereof. 
     
     
         3 . The air freshening device of  claim 1 , wherein the conductive mesh material is about 200 to about 600 mesh. 
     
     
         4 . The air freshening device of  claim 1 , wherein the conductive mesh material is about 400 mesh. 
     
     
         5 . The air freshening device of  claim 1 , wherein the conductive mesh material is formed with 0.001 inch diameter wire. 
     
     
         6 . The air freshening device of  claim 1 , wherein the wick comprises at least one polymer. 
     
     
         7 . The air freshening device of  claim 6 , wherein the wick comprises a porous plastic wick. 
     
     
         8 . The air freshening device of  claim 1 , further comprising a capillary tube underlying the conductive mesh and having an inlet and an outlet, said capillary tube operable to draw liquid from the wick via capillary action and supplying the liquid to the conductive mesh. 
     
     
         9 . The air freshening device of  claim 8 , wherein the capillary tube has an internal diameter of about 0.05 to 0.4 mm and a length of about 5 mm to about 100 mm or about 10 mm to 40 mm. 
     
     
         10 . The air freshening device of  claim 8 , wherein the capillary tube comprises a stainless steel tube or a non-metallic tube. 
     
     
         11 . The air freshening device of  claim 1 , wherein the heater comprises a section of the conductive mesh material located between two spaced apart electrical leads. 
     
     
         12 . The air freshening device of  claim 1 , wherein the power supply includes a supercapacitor that supplies an energy pulse to the heater. 
     
     
         13 . The air freshening device of  claim 1 , further comprising control circuitry operable to apply voltage from the power supply to the mesh in timed heating cycles such that the liquid material is at least partially vaporized after filling of a liquid retention zone of the mesh. 
     
     
         14 . The air freshening device of  claim 1 , wherein the liquid comprises an aqueous liquid fragrance material. 
     
     
         15 . A method for generation of vaporized material comprising:
 drawing liquid into a wick from a liquid supply;   using the wick to deliver the liquid into interstices of a flat layer of mesh material; and   periodically applying voltage across the mesh material to heat the liquid in the interstices of the mesh material to a temperature sufficient to heat the mesh material and at least partially vaporize the liquid such that the liquid is driven out of the interstices of the mesh material and forms a vaporized material.   
     
     
         16 . The method of  claim 15 , wherein the vaporized material forms an aerosol having a substantially uniform particle size, and wherein the aerosol has particles ranging in size from about 0.5 micron to about 4 microns or about 1 micron to about 4 microns. 
     
     
         17 . The method of  claim 15 , wherein the liquid is vaporized in less than about 1 second via heating. 
     
     
         18 . A method for repeated pulsed generation of vaporized material comprising:
 a) generating vaporized material according to the method of  claim 15 ;   b) cooling the mesh material; and   c) repeating steps a) and b).   
     
     
         19 . The method of  claim 18 , comprising cooling the mesh material in less than 10 seconds. 
     
     
         20 . The method of  claim 18 , comprising generating vaporized material every 2 to 100 seconds. 
     
     
         21 . The method of  claim 18 , comprising generating vaporized material at least once an hour. 
     
     
         22 . The method of  claim 18 , comprising periodically applying voltage from a supercapacitor to the mesh material.