Binders are ideal tools for keeping papers and folders organized. Most binders are built around a simple concept involving a piece of cardboard enclosed in plastic, with a metal lock-ring bar (usually three rings) affixed in the middle. There are several variations, with some binders having more rings, different materials and more. As a standard, there are five sizes of binders (based on the lock-ring size): 1/2 inch, 1 inch, 1-1/2 inch, 2 inch and 3 inch. In addition to different sizes, there are also several styles to choose from. The standard plastic-covered binder, fabric-covered binders, zippered binders and more. Similar to other products, there are also binders available for popular brands: children's television programs, for example, along with sports teams and even sitcoms.
Binders begin as a single piece of cardboard, approximately 2 feet in length. The cardboard is coated in a thin layer of adhesive that will hold the plastic cover on. The board is laid on top of one piece of plastic and another is laid over the top, enclosing the cardboard. A machine (similar to a sewing machine) presses the two piece of plastic around their edges, creating a permanent seal. A series of rollers press over the top of the board, smoothing out the plastic and ensuring it has a strong seal. Next, the binder rings are added. The rings come as a single-piece construction consisting of a metal bar, with the rings attached on top. The bar is mounted to the center fold of the binder using a series of pins. A machine presses the pins in to place to permanently attach the bar.
To complete the construction of the binder, each binder goes through a testing process. A worker tests the strength of the binder. The tests are performed in series, each testing a different element of the binder. First, the cardboard is checked for integrity. Next, the plastic seal is checked to ensure the seal is closed. A tool is run along the edge to check for holes and other damages. Finally, the rings are put under a stress test. Several weights are attached to the rings to test a maximum load and endurance. Once the binder is guaranteed good quality, it is passed on for final packaging and shipping. For a final touch, some companies create stickers or inserts with their information, which is added to the binder just before it's packaged. After all of the tests and additional materials are added, the binders are placed back on to a conveyor belt and sent to be packaged and shipped.