| 摘要 |
<p>PURPOSE:To obtain a sealed container of good airtightness simply and with good productivity, by welding the flange and the lid of a liquid containing container by high-frequency induction heating, then releasing pushing pressure after the temperature of a heat welded part is lowered to a temperature at which the saturated vapor pressure of said liquid becomes equal to an atmospheric pressure. CONSTITUTION:A container body 1 which is almost filled with contents containing liquid (e.g. custard pudding, MITSUMAME etc.) is formed, with a flange part 2 remaining, by drawing the laminate of which a thermoplastic (e.g. acid modified PP etc.) film (TPF) 1b is adhered to a substrate 1a composed of relatively stiff material (e.g. tin plate etc.). The lid part 3 composed of a lower layer 3a of TPF (e.g. TPF 1b etc.) heat-weldable with TPF 1b and a substrate (e.g. Al foil etc.) 3b is put on the container body 1 and heat-welded under pressing with a high-frequency induction heating coil apparatus 13 by applying an electric current to a heating coil 14. After the temperature of a joint part is lowered below the boiling point of water, being cooled by passing water through a cooling hole 19, pressing is released. Also, each cycle of pressing, heating and cooling is set by a timer according to the articles.</p> |
