To provide a preform suitably usable in a PET bottle having a stretched expansion, which is expanded downward and freely reversely depressed, provided to a part of its bottle bottom and capable of being formed into the PET bottle having a sufficient strength even if the use amount of a resin is reduced.
The preform 5 is constituted of a mouth 2 and a barrel 16. The barrel 16 is constituted of a cylindrical barrel forming part 17 for molding a bottle barrel 3, a semispherical bottom forming part 18 for molding the bottle bottom 4 and a swell forming part 20 for downward expanding a part of the bottle bottom 4 to mold the swell 10 with a wall, thickness dimension of 0.3-0.7 mm stretched so as to be freely reversely depressed. The wall thickness dimension of the swell forming part 20 is 1.5-3.5 mm. The wall thickness dimension of the swell forming part 20 is set so that the wall thickness dimension of the expanded part 10 reaches 10-40% of that of the swell forming part 20.
| JP2000108195 | MOLD FOR MOLDING BOTTLE WITH HANDGRIP |
| JPS53138469 | METHOD AND APPARATUS FOR PRODUCING HOLLOW ARTICLE |
| JPH0538747 | HOLLOW POLYESTER RESIN BLOW-MOLDED ARTICLE |
SATO TAISUKE
TOMIZAWA KATSUMASA
ONO KOJI
OZAWA HISAHIRO
NAKANE HIROYUKI
| JPS53132064A | 1978-11-17 |
Susumu Hori
Takeshi Sagi
Kenichi Homma
Tsuyoshi Kagaya