| 摘要 |
PROBLEM TO BE SOLVED: To enable stable push-down of a projection by making the push-down of the projection of a hole opening function part achievable in a state of stably supporting at a position of a constant wall thickness, and to obtain excellent formability of the projection in a synthetic resin cup-shaped container that provides the hole opening function part of a suction hole at a bottom plate.SOLUTION: At a bottom plate 3 of a cup-shaped container which is an injection molded product made of synthetic resin, a hole opening function part 4 is formed while avoiding a gate mark 10. At a bottom plate 3 part of a base end peripheral region of a projection 5 for opening a suction hole 9 of the hole opening function part 4, a thick wall part 8 and an easy-to-break thin wall part 7 are formed at a portion located on the side of the game mark 10. By pushing down the projection 5 to the side of the gate mark 10, the thin wall part 7 is broken with the thick wall part 8 being a support point, and the suction hole 9 is stably opened. |
