Container with easily removable membrane lid

Abstract

A container such as a blow-molded plastic can has a flange encircling the top opening, and a flexible membrane lid sealed to the flange. The seal between the lid and the container does not have uniform bond strength all along its length. In particular, the seal has at least one portion having reduced width and hence lower bond strength than other portions of the seal. Consequently, initiation of peeling of the lid from the container can begin relatively easily at the lower-strength portion of the seal. Overall, however, the seal can be relatively strong to resist inadvertent detachment of the lid. Once the peeling of the lid is initiated, it becomes relatively easy to completely detach the lid.

Description

BACKGROUND OF THE INVENTION [0001] 1. Technical Field [0002] This invention relates to a container having a container opening initially closed by a membrane lid sealed to a flange that encircles the opening. [0003] 2. Description of Related Art [0004] Various food and non-food products are packaged in plastic containers or cans formed by blow molding or thermoforming processes. In one such type of container, a flange formed integrally with the container sidewall surrounds the opening of the container. The flange, which can be either a radially inwardly projecting or a radially outwardly projecting flange, provides a surface onto which a flexible membrane closure or lid is attached for initially sealing the container after it is filled with the contents. The consumer peels off the membrane lid to gain access to the contents. If desired, the container can be equipped with an additional overcap for reclosing the container after its initial opening. [0005] The membrane lid is sealed to ...

AI Technical Summary

Benefits of technology

[0008] The present invention addresses the above needs and achieves other advantages, by providing a container wherein the seal between the lid and the container does not have a uniform bond strength all along its length. In particular, the seal has at least one portion having a lower bond strength than other portions of the seal. Consequently, initiation of peeling of the lid from the container can begin relatively easily at the lower-strength portion of the seal. Overall, however, the seal can be relatively strong to resist inadvertent detachment of the lid. Once the peeling of the lid is initiated, it becomes relatively easy to completely detach the lid.

Problems solved by technology

However, with currently available sealants and sealing technology, such accurate control is not possible.

This is due in part to the many factors that can affect the bond strength, many of which are not amenable to being accurately taken into account and controlled.

The drawback to this solution is that the stronger of the seals are often so strong that the consumer has difficulty peeling off the lid.

Images