| 摘要 |
PURPOSE: To easily open a sealed container by providing a body and a closure with a radial inner ear and a radial outer ear formed during the heat sealing operation, and manually pulling the closure and both ears together away from a rim by using a free portion. CONSTITUTION: A seal head comprises a round annular projection 38 extended downward, and a closure material is plunged into a rim by this projection. A land portion, that is, a shoulder portion 40 is extended outwardly in the radial direction from the projection 38. The land portion 40 is projected from a surface 41 located inside of the projection 38 of the seal head. The engagement of the surface 41 by the closure is released during the operation of the heat seal, so that the thickness of a produced root portion 34 is thicker than that of a root portion 32 in some degree, whereby it can endure the inner pressure of the container without being torn. The projection 38 is annular and narrowed to the rim around the most part of the periphery of the rim 6, and is located between the outer land portion 40 and the inner engagement release face 41. The projection is inwardly projected at a position corresponding to a pull tab 10 to form the half-moon shaped land portion, that is, a shoulder portion 46. |
