A cap for a container for a post-foaming gel cleansing composition

Abstract

A container comprises a body of plastics material with a “bag-on-valve” arrangement. The bag depends from a valve and contains a post-foaming gel cleansing composition. A propellant is provided in the container outside the bag, so as to exert a pressure on the post-foaming gel cleansing composition in the bag, such that when the valve stem is depressed to open the valve the post-foaming gel cleansing composition is expelled through the valve stem. The container comprises a cap and the cap is provided with a conduit therethrough to guide the composition from the valve stem to an exit orifice. The conduit comprises an expansion chamber for receiving the composition from the valve stem, a neck having a smaller diameter than the expansion chamber for receiving the composition from the expansion chamber, and a nozzle provided with an exit orifice and having a diameter larger than the neck.

What is claimed is: 
     
         1 . A cap for a container comprising a body containing a bag, the bag depending from a valve and containing a post-foaming gel, and a propellant being provided in the container outside the bag, so as to exert a pressure on the post-foaming gel in the bag, such that when the valve is opened, the post-foaming gel is expelled therethrough; the cap being provided with a conduit therethrough to guide the composition from the valve to an exit orifice, wherein the conduit comprises an expansion chamber for receiving the composition from the valve, a neck having a smaller diameter than the expansion chamber for receiving the composition from the expansion chamber, and a nozzle provided with an exit orifice and having a diameter larger than the neck; characterised by a tapering mouth portion provided between the expansion chamber and the neck. 
     
     
         2 . A cap according to  claim 1  wherein the mouth portion is frustoconical. 
     
     
         3 . A cap according to  claim 1  wherein the diameter of the exit orifice is between 2.5 and 3.5 mm. 
     
     
         4 . A cap according to  claim 3  wherein the diameter of the exit orifice is between 2.7 and 3.3 mm. 
     
     
         5 . A cap according to  claim 3  wherein the diameter of the exit orifice and the nozzle is a substantially constant inner diameter of between 2.5 and 3.5 mm. 
     
     
         6 . A cap according to  claim 3  wherein the diameter of the exit orifice and the nozzle is a substantially constant inner diameter of between 2.7 and 3.3 mm. 
     
     
         7 . A cap according to  claim 1  wherein the nozzle and the exit orifice have a substantially constant diameter of about 3 mm. 
     
     
         8 . A cap according to  claim 1  wherein the expansion chamber and/or the neck and/or the nozzle are cylindrical. 
     
     
         9 . A cap according to  claim 1  wherein the inner diameter of the neck is between 0.7 and 1.1 mm. 
     
     
         10 . A cap according to  claim 9  wherein the inner diameter of the neck is between 0.8 and 1 mm. 
     
     
         11 . A cap according to  claim 9  wherein the inner diameter of the neck is about 0.9 mm. 
     
     
         12 . A cap according to  claim 1  wherein the inner diameter of the expansion chamber is between 2.5 and 3.5 mm. 
     
     
         13 . A cap according to  claim 12  wherein the inner diameter of the expansion chamber is between 2.7 and 3.3 mm 
     
     
         14 . A cap according to  claim 13  wherein the inner diameter of the expansion chamber is about 3 mm. 
     
     
         15 . A cap according to  claim 1  wherein the diameter of the expansion chamber is substantially equal to the inner diameter of the nozzle and/or the exit orifice. 
     
     
         16 . A cap according to  claim 1  wherein the ratio of the inner diameter the nozzle and/or the expansion chamber to the diameter of the neck is from 2.5:0.9 to 3.5:0.9. 
     
     
         17 . A cap according to  claim 16  wherein the ratio of the inner diameter the nozzle and/or the expansion chamber to the diameter of the neck is from 2.7:0.9 to 3.3:0.9 
     
     
         18 . A cap according to  claim 17  wherein the ratio of the inner diameter the nozzle and/or the expansion chamber to the diameter of the neck is about 3:0.9. 
     
     
         19 . A cap according to  claim 1  wherein the length of the neck is between 0.7 and 1.1 mm. 
     
     
         20 . A cap according to  claim 19  wherein the length of the neck is between 0.8 and 1 mm. 
     
     
         21 . A cap according to  claim 20  wherein the length of the neck is about 0.9 mm. 
     
     
         22 . A cap according to  claim 1  wherein the ratio of the length of the neck to the diameter of the neck is from 0.6:1 to 1.5:1. 
     
     
         23 . A cap according to  claim 1  wherein the ratio of the length of the neck to the diameter of the neck is from 0.8:1 to 1:1.2. 
     
     
         24 . A cap according to  claim 1  wherein the ratio of the length of the neck to the diameter of the neck is about 1:1. 
     
     
         25 . A cap according to  claim 2  wherein the length of the frustoconical mouth portion is between 0.3 and 0.4 mm. 
     
     
         26 . A cap according to  claim 25  wherein the length of the frustoconical mouth portion is between 0.32 and 0.38 mm 
     
     
         27 . A cap according to  claim 26  wherein the length of the frustoconical mouth portion is about 0.35 mm. 
     
     
         28 . A cap according to  claim 1  wherein the length of the expansion chamber is from 1 mm to 2 mm. 
     
     
         29 . A cap according to  claim 28  wherein the length of the expansion chamber is between 1.35 and 1.65 mm 
     
     
         30 . A cap according  claim 29  wherein the length of the expansion chamber is about 1.52 mm. 
     
     
         31 . A cap according to  claim 1  wherein the ratio of the length of the expansion chamber to the diameter of the expansion chamber is from 0.75:3 to 2.5:3. 
     
     
         32 . A cap according to  claim 31  wherein the ratio of the length of the expansion chamber to the diameter of the expansion chamber is from 1:3 to 2:3 
     
     
         33 . A cap according to  claim 32  wherein the ratio of the length of the expansion chamber to the diameter of the expansion chamber is about 1.5:3. 
     
     
         34 . A cap according to  claim 1  wherein the expansion chamber and the neck are coaxial. 
     
     
         35 . A container comprising a cap according to  claim 1 . 
     
     
         36 . A container according to  claim 35  comprising a body of plastics material. 
     
     
         37 . A container according to  claim 35  wherein the bag depends from a valve stem, wherein the valve stem is depressed to open the valve;
 wherein the conduit guides the composition from the valve stem to an exit orifice; and 
 wherein the expansion chamber is for receiving the composition from the valve stem. 
 
     
     
         38 . A container according to  claim 35  wherein the post-foaming gel is a post-foaming gel cleansing composition. 
     
     
         39 . A container according to  claim 35  wherein the post-foaming gel comprises a post-foaming agent. 
     
     
         40 . A container according  claim 39  wherein the post-foaming agent is provided at a weight/weight ratio with respect to a base gel of 5:95 to 85:15 
     
     
         41 . A container according to  claim 40  wherein the weight/weight ratio of the post-foaming agent to the base gel is about 10:90. 
     
     
         42 . A container according to  claim 39  wherein the post-foaming agent is a non-polar saturated aliphatic hydrocarbon having from 3 to 6 carbon atoms. 
     
     
         43 . A container according to  claim 42  wherein the post-foaming agent is selected from butane, isobutane, isopentane, n-pentane, n-hexane, 2-methylpentane, 3-methylpentane 2,3-dimethylbutane and 2,2-dimethylbutane, and mixtures thereof. 
     
     
         44 . A container according to  claim 35  wherein the propellant is a non-flammable compressed gas. 
     
     
         45 . A container according to  claim 35  wherein the propellant gas is nitrogen or air. 
     
     
         46 . A container according to  claim 35  wherein the propellant is at a pressure of at least 2.2 to at least 7.3 bar until substantially all of the contents of the bag are dispensed. 
     
     
         47 . A container according to  claim 35  wherein the initial pressure of the propellant, when the bag is filled with gel, but before any gel has been dispensed, is between 6 and 10 bar. 
     
     
         48 . A container according to  claim 47  wherein the initial pressure of the propellant is between 7 and 8 bar.