Historically, the most commonly used plastic food containers were “seal ware,” which was developed over fifty years ago. The sealing mechanism of these containers has had several problems from the start. The soft polyethylene lid and the hard polypropylene container base are structurally designed to give a tight seal so that the contents do not spill and contaminants do not get into the container.
If the lid is sealed securely, though, it makes opening & closing it very difficult. If, however, the appropriate lid is replaced with one that opens more easily, or the lid is only lightly-sealed, the container tends to leak or even worse, spill open completely. It is impossible for seal ware to be made from durable materials and also be easy to open and close. Furthermore, such containers respond inconsistently to changes in temperature. The lid may become excessively loose in the heat of the summer, but difficult to open during the winter months. If you drop one of these containers onto the floor, it would most likely spill open, even if tightly closed. Seal ware is neither convenient, nor secure. In spite of these inconveniences and imperfections, there has been no better alternative…until a few years ago. Hanacobi was born of research that got it right from the beginning, finding the best solution for food storage, in the world’s best plastic container…Lock & Lock. Now, consumers around the world are learning about the superior four-sided locking mechanism of these innovative, convenient, totally airtight containers.