摘要 |
<p>Instead of being moulded by injection of the measured amount of polymer from a single rearward entrance port, which leads to mould wear and flashing of polymer at the delivery end at 15, micropipettes are moulded using an intermediate cavity entrance 14, a first measured body of molten polymer being injected through said entrance and caused or allowed to move forward towards the front end at 15 to at least start to cool and resolidify, and a second measured body of molten polymer being immediately injected through the same entrance 14 and caused or allowed to move rearwardly, and at least start to cool and resolidify, and weld together the two bodies of polymer.</p> |