Method of packaging an adhesive composition and corresponding packaged article

Abstract

The invention relates to a method of packaging an adhesive composition, especially a thermoplastic or thermosetting hot melt adhesive. The method comprises the steps of providing one substantially uniform separate portion of the adhesive composition; sufficiently solidifying said portion for packaging; substantially completely surrounding said sufficiently solidified portion with a plastics packaging material. The packaging material being meltable together with the adhesive composition and blendable into said molten adhesive composition, the kind and amount of said packaging material being chosen so as not to disadvantageously affect the properties of the adhesive composition when blended into same. Preferably, the packaging material is a net, a wrap, a sack or a bag. Packagings made of plastic film are advantageously voided of air, to prevent problems in melting. The packaged adhesive can be melted as it is.

We claim: 
     
       1. A method of packaging a thermoplastic or thermosetting hot melt adhesive, said method comprising the steps of: a) providing one substantially uniform separate portion of an adhesive composition;   b) sufficiently solidifying said portion for packaging;   c) selecting a plastic packaging material having a softening point below about 120° C., and having physical characteristics which are compatible with and do not substantially adversely affect the adhesive characteristics of a molten mixture of said adhesive and said material and whereby said mixture is substantially compatible with the operation of hot melt application equipment;   d) substantially completely surrounding said sufficiently solidified adhesive portion with said plastic packaging material.   
     
     
       2. The method according to claim 1, further comprising, before step b), as a step a) coating the adhesive with a separating, anti-stick substance and pre-cooling the adhesive composition. 
     
     
       3. The method according to claim 1, wherein the packaging material is a wrap, a sack or a bag made of a plastic film or a net or a similar apertured enclosure made of plastic, preferably weighing between 0.1 and 3% by weight with respect to the weight of the adhesive composition contained in the package. 
     
     
       4. The method according to claim 3, wherein the packaging material is a sack or bag sealed by welding after filling with the adhesive composition. 
     
     
       5. A method of packaging a thermoplastic or thermosetting hot melt adhesive, said method comprising the steps of: a) providing a plurality of substantially uniform separate portions of an adhesive composition;   b) sufficiently solidifying all said portions for packaging;   c) forming a batch comprising the plurality of solidified portions,   d) selecting a plastic packaging material having a softening point below about 120° C. and having physical characteristics which are compatible with and do not substantially adversely affect the adhesive characteristics of a molten mixture of said adhesive and said material and whereby said mixture is substantially compatible with the operation of hot melt application equipment;   e) substantially completely surrounding said batch with said plastic packaging material.   
     
     
       6. The method according to claim 5, further comprising, before step b), as a step a) coating the adhesive with a separating, anti-stick substance and pre-cooling the adhesive composition. 
     
     
       7. The method according to claim 5, wherein the packaging material is a sack or a bag made of plastic film or a net or similar apertured enclosure made of plastic, preferably weighing between 0.1 and 3% by weight with respect to the weight of the adhesive composition contained in the package. 
     
     
       8. The method according to claim 5, the portions being provided by separating a continuous mass of adhesive composition into roughly pillow-shaped pieces weighing between 0.1 and 50 grams. 
     
     
       9. The method according to claim 8, the adhesive composition having a high softening point above about 120° C. and the packaging being a sack of plastic film material or a net or similar apertured enclosure made of plastic. 
     
     
       10. The method according to claim 8, the adhesive composition having a low softening point between about 50° C. and 105° C., and the packaging being a bag of plastic film material, said bag being sealed by welding after filling with the adhesive. 
     
     
       11. The method according to claim 10, the bag taking a batch of about 100 to 4000 grams of pillow-shaped adhesive composition portion pieces. 
     
     
       12. The method according to claim 10, the plastics film packaging material having a softening point substantially corresponding to the softening point of the adhesive composition. 
     
     
       13. The method according to claim 10, the plastics film material having a thickness in the range between about 5 μm and 200 μm. 
     
     
       14. The method according to claim 9, the plastic material being selected from the group consisting of ethylene based polymers, including ethylene/vinyl acetate, ethylene acrylate, ethylene methacrylate, ethylene methyl acrylate, ethylene methyl methacrylate, high and low density polyethylene, polyethylene blends and chemically modified polyethylene, copolymers of ethylene and 1-6 mono- or di-unsaturated monomers, polyamides, polybutadiene rubber, polyesters such as polyethylene terephthalate, polybutylene terephthalate; thermoplastic polycarbonates, atactic poly-alphaolefins, including atactic polypropylene, and others; thermoplastic polyacrylamides, polyacrylonitrile, copolymers of acrylonitrile and other monomers such as butadiene styrene; polymethyl pentene, polyphenylene sulfide, aromatic polyurethanes; styrene-acrylonitrile, acrylonitrile-butadiene-styrene, styrene-butadiene rubbers, polyethylene terephthalate, acrylonitrile-butadiene-styrene elastomers, polyphenylene sulfide, A--B, A--B--A, A--(B--A) n  --B, (A--B) n  --Y block polymers wherein the A comprises a polyvinyl aromatic block, the B block comprises a rubbery midblock which can be partly hydrogenated, and mixtures of said substances. 
     
     
       15. The method according to claim 9, the adhesive composition portion pieces being cooled to ambient or below ambient in a cooling bath at least on their outsides and thereafter conveyed to a netting or bagging station for packaging. 
     
     
       16. The method according to claim 10, the bag filled with the adhesive composition portion pieces being weld-sealed. 
     
     
       17. The method according to claim 10, at least most of the air remaining in the bag after filling being removed, bringing the packaging film material into close contact with the adjoining adhesive composition pieces. 
     
     
       18. The method according to claim 17, the filled and sealed bag being compressed or evacuated, and air being forced out from around and between the portion pieces and out of the bag through pores, punctures and perforations in the film material and/or through openings in the weld seam, the batch of adhesive composition pieces being compacted and the packaging film material being adhered to the surfaces of the compacted batch. 
     
     
       19. The method according to claim 18, the adhesive in the bag being sufficiently re-heated before compression or allowed to retain sufficient internal heat in the cooling step to facilitate deformation of the packaged adhesive composition portion pieces during compression. 
     
     
       20. The method according to claim 18, the compression being provided by means of a press. 
     
     
       21. The method according to claim 18, the compression being provided by the weight of the stacked filled bags under the influence of elevated ambient temperature, especially through stacking the bags in delivery boxes, crates, cartons and such like, and storing same in a sufficiently heated room. 
     
     
       22. The method according to claim 18, the compression being carried out at an elevated temperature of 30° C. to 150° C. 
     
     
       23. A method of packaging a thermoplastic or thermosetting hot melt adhesive, said method comprising the steps of: a) providing an adhesive composition in flowable form, . .sufficiently plastified.!. for packaging;   b) inserting at least one portion of said flowable. .,plastified.!. adhesive composition into a plastics packaging material enclosure;   c) selecting a packaging material having a softening point below about 120° C. and having physical characteristics which are compatible with and do not substantially adversely affect the adhesive characteristics of a molten mixture of said adhesive and said material and whereby said mixture is substantially compatible with the operation of the hot melt application equipment; and   d) separating and substantially surrounding said at least one portion with said plastics packaging material.   
     
     
       24. The method according to claim 23, further comprising, before step b), . .as a.!. .Iadd.and after .Iaddend.step a) .Iadd.an additional step a') .Iaddend.coating the adhesive with a separate, anti-stick substance and pre-cooling the adhesive to a flowable. ., plastified.!. state. ., of the adhesive composition.!.. 
     
     
       25. The method according to claim 23, wherein the packaging material enclosure is a sack or a bag made of plastic film or a net or a similar apertured enclosure made of plastic, preferably weighing between 0.1 and 3% by weight with respect to the weight of the adhesive composition contained in the package. 
     
     
       26. The method according to claim 25, wherein the packaging material enclosure is a sack or bag sealed by welding after filling with the adhesive composition. 
     
     
       27. The method according to claim 23, wherein the flowable. ., plastified.!. composition has a softening point temperature of between 50° C. and 100° C. 
     
     
       28. The method according to claim 23, wherein the flowable. ., plastified.!. composition is provided by means of a melt extruder having cooling means for adjusting the temperature of the extrudate. 
     
     
       29. The method according to claim 1, the plastic packaging material having a melting or softening point of below about 125° C. 
     
     
       30. The method of claim 8 wherein the softening point of the adhesive is below 120° C. 
     
     
       31. The method of claim 8 wherein the softening point of the adhesive is about 80° C. 
     
     
       32. The method of claim 8 wherein the batch is about 250 to 1000 grams. 
     
     
       33. The method of claim 10 wherein the film thickness is 15 μm to 50 μm. 
     
     
       34. The method of claim 1 wherein the packaging material has a softening point of about 90° C. to 120° C. 
     
     
       35. A method of packaging a synthetic block polymer based hot melt adhesive, said method comprising the steps of: (a) providing one substantially uniform separate portion of an adhesive composition comprising a synthetic block polymer based hot-melt adhesive;   (b) sufficiently solidifying said portion for packaging;   (c) selecting a polyethylene packaging material which is meltable together with the adhesive composition and blendable into the adhesive composition in a molten state, said packaging material being chosen so as to not disadvantageously effect the properties of the adhesive composition when blended into same, and to be substantially compatible with the operation of hot melt application equipment; and   (d) substantially completely surrounding said sufficiently solidified portion with said polyethylene packaging material.   
     
     
       36. The method according to claim 35 wherein said film material has a thickness in the range between about 5 μm and 50 μm. 
     
     
       37. The method according to claim 35 wherein said film material has a softening point below about 120° C. 
     
     
       38. The method of claim 1 comprising the additional step of applying said molten mixture through hot melt application equipment having an orifice less than about 0.025 inches in diameter. 
     
     
       39. The method of claim 5 comprising the additional step of applying said molten mixture through hot melt application equipment having an orifice less than about 0.025 inches in diameter. 
     
     
       40. The method of claim 23 comprising the additional step of applying said molten mixture through hot melt application equipment having an orifice less than about 0.025 inches in diameter. .Iadd. 
     
     
       41.  A method of packaging a thermoplastic or thermosetting hot melt adhesive, said method comprising the steps of: a) providing an enclosure comprising a film material having a softening point below about 120° C., said film material being compatible with and not substantially adversely affecting the adhesive characteristics of a molten mixture of said adhesive and said material, and the operation of hot melt application equipment;   b) extruding a hot melt adhesive directly into said enclosure until a desired amount of adhesive is received; and   c) sealing said enclosure to substantially surround said hot melt adhesive. .Iaddend..Iadd.42. The method according to claim 41 wherein the adhesive has a softening point between about 50° C. and 100° C. .Iaddend..Iadd.43. The method according to claim 41 wherein the film material has a softening point of about 90° C. to 120° C. .Iadd.44. A method of packaging a thermoplastic or thermosetting hot melt adhesive, said method comprising the steps of:   a) providing an enclosure comprising a film material having a softening point below about 120° C., said film material being compatible with and not substantially adversely affecting the adhesive characteristics of a molten mixture of said adhesive and said material, and the operation of hot melt application equipment;   b) filling said enclosure with hot melt adhesive until a desired amount of adhesive is received;   c) sealing said enclosure to substantially surround said hot melt adhesive.   
     
     
        .Iaddend..Iadd.45.  The method according to claim 44 wherein the adhesive has a softening point between about 50° C. and 100° C. .Iaddend..Iadd.46. The method according to claim 44 wherein the film material has a softening point of about 90° C. to 120° C. .Iaddend..Iadd.47. A method of packaging a hot melt adhesive, the method comprising forming a film material enclosure substantially surrounding a thermoplastic hot melt adhesive composition having a softening point less than about 120° C., the adhesive comprising a thermoplastic polymer and a tackifying resin, the film material having a softening point less than about 125° C., being compatible with and not substantially adversely affecting the adhesive characteristics of a molten mixture of said adhesive and said film material. .Iaddend..Iadd.48. The method of claim 1 wherein the packaging material has a sharp melting point. .Iaddend..Iadd.49. The method of claim 5 wherein the packaging material 
     
     
        has a sharp melting point. .Iaddend..Iadd.50.  The method of claim 23 wherein the packaging material has a sharp melting point. .Iaddend..Iadd.51. The method of claim 35 wherein the packaging material has a sharp melting point. .Iaddend..Iadd.52. The method of claim 41 wherein the film material has a sharp melting point. .Iaddend..Iadd.53. The method of claim 44 wherein the film material has a sharp melting point. .Iaddend..Iadd.54. The method of claim 47 wherein the film material has a sharp melting point. .Iaddend..Iadd.55. The method according to claim 47 wherein the film material has a sharp melting point. .Iaddend.