| 摘要 |
An inventive powder composition comprises one or more than one finely divided resin chosen from a thermoplastic degradable copolyester resin containing both aliphatic and aromatic groups, a degradable UV curable polyester, a mixture of a cyclic oligomeric polyester resin, a ring opening polymerization catalyst and a degradable polyester, a degradable thermosetting polyester resin and mixtures thereof, the powder having an average particle size or diameter, as determined by laser light scattering, of from 30 to 125 mu m. The composition provides thin, degradable coatings for foamed and biodegradable substrates, e.g. starch disposal articles. An apparatus for holding foam or light weight substrates comprises one or more than one perforated female pattern or jig molded in the shape of a substrate and a stand for holding said jig(s) having within it at least one enclosed chamber attached to one or more than one vacuum line, wherein the perforations in each of said jig(s) lead into said enclosed chamber. Coatings may be provided by placing a substrate in the jig, applying the powder composition to the substrate, and heating the substrate to flow out or melt said powder and to, with vacuum assistance, coalesce the melt or flow out to form a film to thoroughly coat the substrate. |
