| 摘要 |
PROBLEM TO BE SOLVED: To make an extremely favorable circularity of an opening and prevent transfer defects or fitting defects of covers on a charging machine, by forming triangular corner-filling parts at both sides of the peripheral part of the opening of a reinforcing body welded with heat at the inside of a paper container and the connection part of a column. SOLUTION: A synthetic resin reinforcing frame body 200 constituted of the peripheral part 210 of the opening, a column 220, and a circular bottom 230, is welded with heat at the inside face of a cup-shaped paper container 100 made of a laminated material provided with synthetic resin layers like polyethylene at the outermost layer and the innermost layer chiefly made of a paper layer. And triangular corner-filling parts 240 continuously extending from the underface or the opening peripheral edge 210 to the side face of the column 220, is formed at both sides of the connection part of the opening peripheral edge 210 of the reinforcing frame body 200 and the column 220. In this way, the rigidity of the opening peripheral edge 210 is made stronger than the rigidity of the sticking part of the cup-shaped paper container 100 and the restoring force of the laminated materials chiefly made of the curled paper layer and the circularity of the opening 110 is kept favorable. |
