| 摘要 |
<p>Escape of gas or vapor from within a material, having a thermoplastic layer, is facilitated by applying a layer as a coating composition in the form of a froth. When the froth is heated to fuse the composition into a solid layer, the froth collapses leaving perforations extending through the fused layer from the surface to the interior of the material. In a preferred embodiment, there is provided a porous substrate (1) having on one face a backcoat (2) with perforations (3) extending between the substrate and the free surface of the backcoat. On the other face of the substrate (1) a foamed layer (4) carrying a decorative ink pattern (5) is covered by a clear wear layer (6).</p> |
