| 摘要 |
<p>The invention is comprehend with rigid thermoplastic sheet material of which the polymeric constituent is predominantly vinyl chloride polymer. The sheet contains glass fibres lying in, or substantially in, the plane of the sheet the amount of glass fibre being in the range 3 to 30 per cent by weight of the material. A particulate filler is also present in the sheet in an amount in the range 20 to 50 per cent by weight, the amount of the polymeric constituent of the sheet being 30 to 75 per cent by weight. A sheet is conveniently made by building up successive very thin layers on a calender roll to ensure that the fibres are lying in the plane of the sheet. Several such sheets are then laminated together under heat and pressure. An extra reinforcing layer of a material such as a cloth, mat or scrim can be incorporated into the sheet, for example by including the reinforcing layer between laminations in the manufacture of the sheet. The resultant rigid sheets are suitable for moulding. If desired decorative surface layers can be laminated onto the sheets and the sheets are then suitable for use, for instance, as wall panelling.</p> |
