Strictly speaking, Velcro® is a registered trademark describing a specific brand of "hook and loop fasteners." The product name has proven so popular, however, that it has become the generic term for any two piece fastener with nylon hooks on one side and a mat of loops on the other. Velcro® has become very popular in the clothing, shoe, and automotive industries (among others) for its ability to provide a firm grip under tension but come apart easily when necessary.
The story of Velcro® begins with a hike in the Swiss woods in 1948. Inventor George de Mestral noticed that he and his dog were coated with cockleburr seed casings. Under a microscope, de Mestral discovered that the seed casings contained numerous tips with hook-shaped ends. It was these natural hooks which clung so stubbornly to the loose weave of his pants and the dog's fur. George de Mestral believed that a fastening device made from a similar hook and loop design could rival the metal zipper in popularity and versatility.
After several attempts to create a suitable prototype, de Mestral and a French fabric designer finally discovered a way to use nylon fibers under an infrared lamp to create the necessary hooks. Matted nylon fibers would also form the field of loops needed to complete the adhesive process. The name VELCRO was formed from the French words VELour(velvet) and CROchet(hook). De Mestral officially formed the Velcro® company in Switzerland in the early 1950s and received patents from virtually every industrialized country in the world.
Velcro® works on the principle that enough hooks on one side of a fastener would become tangled in enough loops on the other side to form a very strong bond. Applying pressure to a section of velcro can only make it stronger as more loops and hooks connect. Yet if only a few hooks and loops are pulled apart with force, the rest of the Velcro® will follow with a distinctive ripping sound. Velcro® sections held under tension, such as a pulley system, can prove to be incredibly strong. This is why shoe manufacturers often place slots through which Velcro® closers are pulled. The added tension of a pulley keeps the bond strong.
Velcro® is also popular in the clothing industry. Waistbands in costumes, skirts and pants can be easily adjusted with Velcro® fasteners. Costumes with Velcro® fasteners can be torn away from the body quickly between scenes. Other industries use Velcro® strips to store tools or attach fiberglass parts to frames. Large patches of Velcro® can easily support hundreds of pounds. Wallets and backpacks, on the other hand, may only need a small swatch in order to keep flaps and sections secure. Practically everyone can find at least one product in their homes or cars which use some form of Velcro® brand hook and loop fasteners.