| 摘要 |
<p>The invention relates to a composition for providing a vapour or moisture barrier coating for flexible wood fibre material, reprocessable as paste material, which comprises a polymer emulsion providing a moisture and vapour barrier and wherein said polymer in emulsion has a particle size distribution finer than 10 micro m, the polymer being selected from the group consisting of polyvinylidene chloride, vinylidene chloride copolymer, methyl methacrylate and acrylonitrile and mixtures thereof, characterized by containing a particulate additive, selected from the group consisting of hydrated aluminum silicate, calcium carbonate, a polyvinyl acetate homopolymer, and mixtures thereof having an average particle size of less than 10 micro m, the particulate material being capable of interstitial combination with said particles of polymer and forming a coating on the flexible material which preserves the moisture and vapour barrier properties, provided by the polymer and which, upon reprocessing as paste breaks up into pieces smaller than 1.6 mm generally, the composition having a pH ranging between a value lower than or equal to approximately 2 and 6..7. The invention also relates to a process of reprocessing flexible, fine wood fibre material having a moisture and vapour barrier coating. This allows the recovery as valuable paper products of some flexible packaging with moisture and vapour barrier coating.</p> |
