| 摘要 |
A permeable belt comprises a woven or non-woven substrate encapsulated in synthetic plastics material and abraded on its major surfaces to expose hollow or soluble yarns, which may be weft yarns (11) of a woven fabric, needled fibres (22) of a needlefelt, or pile loops (31) of a tufted pile fabric. Soluble yarns are dissolved in, e.g., water and hollow yarns breached by abrasion to provide voids or passages extending through the belt. |
