| 摘要 |
1. Claims for the Contracting States : BE, CH, DE, FR, GB, IT, LI, LU, NL, SE Glues based on aqueous latex of plasticised vinyl acetate polymer containing at least one polyvinyl alcohol as a protective colloid, characterised in that, in the latex, the concentration in respect of dry materials is from 50 to 70% by weight, the size of the particles of vinyl acetate polymer having a molecular mass by weight of 10 000 to 300 000 is from 0,1 to 3 mu m, the polyvinyl alcohol or alcohols represent from 0,5 to 3% by weight of the polymer and any plasticising agent may represent from 0 to 30% by weight of the polymer, and that the setting time thereof is less than 10 seconds. 1. Claims for the contracting State : AT A process for preparing glues having a setting time of less than 10 seconds, based on aqueous latex of plasticised vinyl acetate homopolymer or copolymer, in which the concentration in respect of dry materials is from 50 to 70% by weight and the size of the particles of vinyl acetate polymer having a molecular mass by weight of from 10 000 to 300 000 is from 0,1 to 3 mu m, which comprises polymerising in aqueous emulsion vinyl acetate alone or with at least one copolymerisable monomer, in the presence of at least one polyvinyl alcohol, then possibly adding at least one plasticising agent to the latex formed, and is characterised in that the polymerisation medium whose pH-value is from 2,5 to 6, contains water, from 40 to 65% by weight of the medium of vinyl acetate or a copolymerisable monomer-vinyl acetate mixture, from 1 to 10% by weight of the monomer or monomers of at least one chain limiting agent and from 0,5 to 3% by weight of the mixture of monomer(s) and chain limiting agent of at least one polyvinyl alcohol, and that the plasticising agent represents from 0 to 30% by weight of the polymer formed. |
