| 摘要 |
<p>A specially reinforced sodium kraft paper which is mechanically strong, waterproof and grease proof is made up of an outerlayer of wood-free kraft paper, weighing 60-100 (72)g/m2, an outer layer of pergamyne (synthetic parchment) weighing approx. 65g/m2, and an intermediate layer of polythene reinforced with glass fibre fabric weighing 25-35g/m2. The two outer layers are combined by spraying molten polythene on the inner side of one while simultaneously feeding in the glass fibre fabric and rolling on the second outer layer to form the sandwich.</p> |
