Water soluble package

Abstract

A package containing an agrochemical composition which package contains a first sheet of non-planar water soluble or water dispersible material defining a concavity enclosing the agrochemical composition and a second sheet of water soluble or water dispersible material sealed to the first sheet by a continuous closed water soluble or water dispersible seal.

1 . A package containing an agrochemical which package comprises a first sheet of non-planar water soluble or water dispersible material and a second sheet of water soluble or water dispersible material superposed on the first sheet and sealed to it by a continuous closed water soluble or water dispersible seal along a continuous region of the superposed sheets.  
     
     
         2 . A package according to  claim 1  wherein the agrochemical is a plant protection agent, a plant growth regulator or a plant nutrient.  
     
     
         3 . A package according to  claim 1  wherein the agrochemical is a pesticide.  
     
     
         4 . A package according to  claim 1  wherein the agrochemical is an insecticide, fungicide, herbicide, acaricide or nematocide.  
     
     
         5 . A package according to any one of the preceding claims wherein the water soluble seal is a water soluble heat seal.  
     
     
         6 . A package according to any one of the preceding claims wherein the second sheet is sealed to the first sheet along a substantially planar continuous region of the superposed sheets.  
     
     
         7 . A package according to any one of the preceding claims wherein the first and second sheets are made of the same material.  
     
     
         8 . A package according to  claim 7  in which the first and second sheets each comprise a laminate of at least two layers of water soluble or water dispersible material.  
     
     
         9 . A package according to  claim 8  which comprises two layers each having a thickness from 20 μm to 1 mm.  
     
     
         10 . A package according to any one of the preceding claims in which the pesticidal composition is in liquid or gel form.  
     
     
         11 . A package according to any one of  claims 1  to  7  containing a pesticidal composition in solid form in which each of the first and second sheets comprises a single layer of water soluble or water dispersible material.  
     
     
         12 . A package according to  claim 11  in which the sheet has a thickness from 20 to 500 μm.  
     
     
         13 . A package according to any one of the preceding claims which contains from 1 ml to 10 litres of pesticidal composition in liquid or gel form or from 0.1 grams to 7 kg of pesticidal composition in solid form.  
     
     
         14 . A package according to any one of  claims 1  to  13  which contains from 0.1 litres to 1.5 litres of agrochemical composition in liquid or gel form.  
     
     
         15 . A package according to any one of the preceding claims in which the heat seal is a single continuous seal not comprising any angular intersections with itself.  
     
     
         16 . A package according to any one of  claims 1  to  14  wherein the seal is curved.  
     
     
         17 . A package according to any one of  claims 1  to  14  wherein the seal is curved, with the radius of curvature of the seal being from 1 mm to half the width of the package.  
     
     
         18 . A package according to any one of claims  1  to  14  wherein the seal is curved, with the radius of curvature of the seal being from 5 mm to half the width of the package.  
     
     
         19 . A package according to any one of the preceding claims in which the water soluble or dispersible material comprises polyethylene oxide, methyl cellulose or a polyvinyl alcohol.  
     
     
         20 . A package according to  claim 19  in which the water soluble or water dispersible material comprises a cold water soluble polyvinyl alcohol which is 40 to 99% hydrolysed or alcoholised polyvinyl acetate.  
     
     
         21 . A package according to any one of the preceding claims in which the contents are released in less than 10 minutes after contact with water.  
     
     
         22 . A package according to  claim 21  in which the contents are released in less than 1 minute.  
     
     
         23 . A package according to any one of the preceding claims which comprises a region which will more readily dissolve than the rest of the package.  
     
     
         24 . A package according to any one of the preceding claims in which the chemical comprises a hydroxybenzonitrile herbicide.  
     
     
         25 . A package according to  claim 24 , in which the hydroxybenzonitrile herbicide comprises a mixture of ioxynil and bromoxynil esters.  
     
     
         26 . A process for producing a package as claimed in any one of the preceding claims which comprises: moulding a first sheet of water soluble or water dispersible material to form a non-planar sheet comprising at least one recess adapted to retain an agrochemical composition, said recess being bounded by a flange; placing an agrochemical composition in the at least one recess; placing a second sheet of water soluble or water dispersible material on the flange and across the or every recess; and sealing the first and second sheets along the flange to form a continuous water soluble or water dispersible seal.  
     
     
         27 . A process according to  claim 26  in which the recess is bounded by a substantially planar flange.  
     
     
         28 . A process according to  claim 26  or  27  in which the sealing of the first and second sheets is effected by heat sealing.  
     
     
         29 . A process according to  claim 26 ,  27  or  28  in which the first water soluble or water dispersible sheet is deformed by vacuum-forming to conform to a mould.  
     
     
         30 . A process according to  claim 26 ,  27  or  28  wherein the first water soluble or water dispersible sheet is deformed by thermo-forming.  
     
     
         31 . A process according to any one of  claims 26  to  30 , in which the first and second sheets are heat sealed at a sealing temperature of from 140 to 220° C.  
     
     
         32 . A process according to any one of  claims 26  to  31  in which the first and second sheets are heat sealed at a sealing jaw pressure from 1×10 −4  to 3.5×10 −4  kg/m 2 .  
     
     
         33 . A process according to any one of  claims 26  to  32  in which the first and second sheets are heat sealed with a dwell time from 0.2 to 1.5 seconds.  
     
     
         34 . A process according to any one of  claims 26  to  33  in which the first and second sheets are heat sealed at a relative humidity from 15 to 85%.  
     
     
         35 . A package according to  claim 1  and substantially as hereinbefore described.  
     
     
         36 . A process according to  claim 26  and substantially as hereinbefore described.