| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a cardboard base paper for a paper container which efficiently stops increase of the internal pressure caused by heating and reduces the manufacturing cost when used as a sealed container; and the paper container. SOLUTION: On a flange section 22 which extends to the outside from the upper end edge of the peripheral wall section 15b of this paper container, a second opening 26c is formed by the expansion of a confronted edge 31 of a second slit 20c at the time of a press-molding. On the upper surface of the flange section 22, a protective film 33 is pasted through a seal section 34. When the paper container is heated, and the pressure in the container increases, the protective film 33 is lifted, and the range of a peeling section 35 is extended to the outside. Then, when the peeling section 35 reaches the second opening 26c, a vapor or the like becoming the cause for the increase of the internal pressure is discharged to the outside through the second opening 26c. Then, a state wherein the outer peripheral end section of the protective film 33 is held by the flange section 22 is kept, and the internal pressure is prevented from increasing further.</p> |
