| 摘要 |
This disclosure relates to a pressure resisting plastic bottle having a neck portion, a body portion and a bottom portion integrally formed of polyethylene terephtalate and comprising a bottom wall portion biaxially molecular oriented together with a body wall portion, an inwardly inclined outer peripheral wall portion, an inner peripheral wall portion turned back from the lower end of said outer peripheral wall portion toward the inside and a bottom wall central portion in the form of a convex curved surface formed continuous to the upper portion of the inner peripheral wall portion, whereby an angle beta , included between the vertical and said outer peripheral wall portion is greater than an angle alpha included between the vertical and said inner peripheral wall portion. Curved inner and outer corners of an annular portion in contact with ground and formed about the lower ends of the respective inner and outer peripheral wall portions, and another curved corner at the juncture between the inner peripheral wall portion and the bottom wall central portion are formed so that the radius of curvature r1 of the outer corner is greater than the radius of curvature r2 of the inner corner, and the radius of curvature r3 of said another corner is greater than said curvature r1. |
