Covering impregnated with insecticide

Abstract

A covering for soft furnishing is impregnated with an insecticide, such as permethrin. The concentration of permethrin is sufficient to kill house dust mites and deter larger insects such as fleas and ticks. The insecticide is released from the covering over an operational period so as to encourage the absorption of the insecticide into surrounding soft furnishings. The covering is manufactured from machined fabric, such as knitted voile, having interstices sufficiently small to reduce the rate of insecticide release over the operational period.

What we claim is:  
     
         1 . A covering for soft furnishing, impregnated with an insecticide wherein said insecticide is released from said covering over an operational period so as to encourage the absorption of said insecticide into said soft furnishing, comprising 
 a covering manufactured from machined fabric having interstices sufficiently small to reduce the rate of insecticide release over said operational period.    
     
     
         2 . A covering according to  claim 1 , configured to be applied to mattresses, duvets, pillows cushions, pet beds, or other bedding elements.  
     
     
         3 . A covering according to  claim 1 , wherein said insecticide is a synthetic pyrethroid.  
     
     
         4 . A covering according to  claim 3 , wherein said synthetic pyrethroid is permethrin, deltamethrin, sypermethrin, allethrin or bifenthrin.  
     
     
         5 . A covering according to  claim 1 , wherein said fabric is machined from a polyester yarn.  
     
     
         6 . A covering according to  claim 5 , wherein said polyester yarn has a gage in the range of twenty to one hundred decitex.  
     
     
         7 . A covering according to  claim 1 , wherein the interstices of the fabric are smaller than that provided by a machined netting.  
     
     
         8 . A covering according to  claim 7 , wherein said machined fabric is a knitted voile.  
     
     
         9 . A covering according to  claim 8 , wherein said knitted voile is machined on a warp knitting machine with two guide bars to provide a voile denser than curtain voile.  
     
     
         10 . A covering according to  claim 8  or  claim 9 , wherein said voile has between twenty-five to thirty-five courses per centimetre and between eight to fifteen whales per centimetre.  
     
     
         11 . A covering according to  claim 8 ,  claim 9  or  claim 10 , wherein the fabric has a weight of between thirty-five to forty-five grams per square metre.  
     
     
         12 . A covering according to  claim 1 , containing between four hundred to seven hundred milligrams of insecticide per square metre.  
     
     
         13 . A covering for soft furnishings, impregnated with permethrin with a loading of between five hundred and six hundred milligrams per square metre and configured to release permethrin over an operational period of between one-and-a-half and two-and-a-half years to give a final loading of between one hundred to two hundred milligrams per square metre.  
     
     
         14 . A covering according to  claim 13 , fabricated totally or in part of a knitted voile.  
     
     
         15 . A covering according to  claim 14 , wherein said voile is knitted from polyester yarn.  
     
     
         16 . A cover according to  claim 15 , wherein said polyester yarn has a gauge in the range of twenty to one hundred decitex.  
     
     
         17 . A method of producing a covering for soft furnishings configured to provide protection against house dust mites, comprising the steps of 
 knitting a voile from a polymer yam;    machining a cover from said knitted voile; and    impregnating said machined cover with an insecticide.    
     
     
         18 . A method according to  claim 17 , wherein said polymer yarn is polyester yam having a gauge of between twenty to one hundred decitex.  
     
     
         19 . A method according to  claim 17 , wherein said polymer yarn is knitted on a warp knitting machine with two guide bars.  
     
     
         20 . A method according to  claim 17 , wherein said knitted voile has a weight of between twenty-five to forty-five grams per square metre.  
     
     
         21 . A method according to  claim 17 , wherein said machined cover is impregnated by being immersed in an impregnation fluid and then rolled between rollers to control the level of fluid pick-up.  
     
     
         22 . A method according to  claim 21 , wherein said rolled voile is passed through drying means to remove water from said insecticide.  
     
     
         23 . A method according to  claim 21 , wherein said impregnation fluid is a suspension of permethrin in water.  
     
     
         24 . A method according to  claim 23 , wherein said impregnation fluid is mixed by adding permethrin in organic solution to water to provide said suspension of permethrin in water.  
     
     
         25 . A method according to  claim 24 , wherein said organic solution contains from fife to fifty percent permethrin.  
     
     
         26 . A method according to  claim 24 , wherein between fifty and ninety millilitres of organic solution are added to each litre of water.  
     
     
         27 . A method according to  claim 21 , wherein an insecticide loading of between four hundred and seven hundred milligrams per square metre is achieved by a wet pick-up of between fifty to eighty percent.  
     
     
         28 . A method according to  claim 27 , wherein said insecticide is permethrin.