| 摘要 |
A foamed polyurethane material is hotpressed to a required shape while at a temperature below its melting point. The substance may contain synthetic or natural fibres. The heating may be by electrical resistances or by a high frequency alternating field produced between mould parts formed as electrodes. The moulds may also emboss, stamp, or cut the material. A sheet of the foamed material may be passed between heated shaped metal rolls to form waffle-like grooving on one or both sides to make the sheet flexible. Sheets of such material may be coated on one or both sides by textile fabric. |
