| 摘要 |
PURPOSE: To reliably seal even a liquid container having a polyester-based sealing layer in the inner surface thereof with respect to a method for hermetically sealing a liquid paper container in a sealing process in a liquid-filling device. CONSTITUTION: Firstly, inner sealing surfaces 21 previously provided on an inner surface 2 of an open part of a liquid paper container 1 shaped into a square tube form are so folded as to be proximately opposed to each other. Next, the opposed inner sealing surfaces 21 are contact bonded to each other from outside, and a high-frequency electromagnetic wave is applied to a metal film provided under the inner sealing surfaces 21. An inner layer material of a thermoplastic resin or the like forming the inner sealing surfaces 21 is heated through the metal film for hermetically sealing a liquid paper container. |
