Cooler Bag Technology
The original ice chest was made out of galvanized metal. Later versions were made from hard plastic. They were double-walled with a layer of dense Styrofoam in between which helped to keep the contents cool. Today's ice chests are still made this same basic way.
Styrofoam is a suitable insulator, but it must be relatively thick to maintain internal temperature for long periods of time. And, of course, styrofoam dents and cracks easily, so it has to be encased in a hard case to prevent cracking. Therefore, the freezer must be rigid.
By contrast, cooler bags are not rigid. Instead, they are usually made from heavy but flexible fabrics, like polyester, on the outside. The inside is lined with heavy duty foil. In between the outer and inner layers are layers of materials like flexible foam, which are thin but dense and have the ability to maintain internal temperatures for several hours. This technology allows for a bag that is flexible and thin and, therefore, easy and convenient to transport. Also, unlike their rigid predecessors, cooler bags can be manufactured in a wider variety of sizes and shapes.
Xiamen Obaili Manufacturing Ltd. has been specialized in making bags for 17 years. We are a professional bags manufacturer and exporter, focusing on the design, development and production of cooler bags,drawstring bags, duffel bags, backpacks, briefcases, diaper bags, tool bags and other outdoor leisure bags for travel, sports and camping.