| 摘要 |
Provided is a process for thermoforming a gas and liquid permeable layer (10) of thermoplastic material having an average thickness of less than 1.0 mm, the process comprising the steps of bringing the layer of thermoplastic material, at a temperature below that required for thermoforming, into contact with a mould (16) at a temperature above that of a thermoforming temperature of the thermoplastic material; pressing the mould into contact with the layer of thermoplastic material, the contact between mould and thermoplastic material causing heat to transfer from the mould to the thermoplastic material and raising the temperature of the thermoplastic material to a thermoformable temperature; such pressing thereby causing thermoforming of the thermoplastic material to conform to the shape of the mould. |
