| 摘要 |
<p>A web-winding core is formed as a hollow cylindrical shell or tube, the shell being a three-layered sandwich comprising internal and external skins 12, 14, between which is a filler 16 to which the inner and outer skins 12, 14 are bonded. The filler 16 may be a lightweight natural material such as balsa or cork, a cellular material or an artificial foamed polymer. The internal and external skins 12, 14 may be reinforced composite material such as reinforcing fibres within a matrix, which may be a polymer compound including a modified polymer resin with a urethane acrylate additive. The reinforcing fibres pre-impregnated with an uncured polymer and may be natural or artificial fibres such as aramid or hemp. A ring 40 of tough, resilient material such as metal or a urethane polymer may be formed at the ends of the core to protect it from damage, which ring 40 may be chamfered 44 to facilitate insertion of handling apparatus into the core. The ring 40 may have the same inner and outer diameters as the core.</p> |
