Elastic bands

A rubber band (also known as an elastic or gum band) is a loop of rubber, usually ring shaped, and commonly used to hold multiple objects together. The rubber band was patented in England on March 17, 1845, by Stephen Perry. Most rubber bands are manufactured out of natural rubber, and are sold in a variety of sizes.

Rubber bands are made by extruding the rubber into a long tube to provide its general shape, putting the tubes on mandrels, curing the rubber with heat, and then slicing it across the width of the tube into little bands. This causes the tube to split into multiple sections, creating a rubber band.

While other rubber products may use synthetic rubber, most rubber bands are primarily manufactured using natural rubber because of its superior elasticity.

Natural rubber originates from the latex of the rubber tree, which is acquired by tapping into the bark layers of the rubber tree. Rubber trees belong to the spurge family (Euphorbiaceae) and live in warm, tropical areas. Once the latex has been "tapped" and is exposed to the air, it begins to harden and become elastic, or "rubbery". Rubber trees only survive in hot, humid climates near the equator and so the majority of latex is produced in the Southeast Asian countries of Malaysia, Thailand, and Indonesia.

A rubber band has three basic dimensions: length, width, and thickness. (See picture.)

A rubber band's length is half its circumference. Its thickness is the distance from the inner circle to the outer circle, and its width is the distance from one edge to the other.

If one imagines a rubber band during manufacture, that is, a long tube of rubber on a mandrel, before it is sliced into rubber bands, the band's width is decided by how far apart the slices are cut.

A rubber band is given a standard or quasi-standard number based on its dimensions.

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