Some flowering plants and trees (around 10%) produce a fluid called latex that they secrete when damaged as a defence reaction to plant-eating insects and animals. Latex, which is different to sap, is a milky fluid present in the stems and roots of these plants that coagulates when exposed to air and is the raw material for natural latex or, with further processing, natural rubber.
The primary source of commercial natural rubber is the Hevea tree, commonly referred to as the rubber tree or rubber plant. Its Latin botanical name is Hevea brasiliensis, which gives a clue to its origin in the Amazon rainforest of South America. As demand for rubber grew and vulcanisation (the methods used to harden rubbers) was developed through the 1800s, attempts were made to grow and establish commercial rubber tree plantations outside of Brazil. The species only grows in a tropical climate, and today most commercial rubber is grown and produced in South and Southeast Asia, but it is also grown in other tropical and suitable sub-tropical regions such as West Africa. Hevea trees need to be at least five years old before they can be tapped for latex – the process of stripping off a sliver of bark then making a cut across the latex vessels that grow in a spiral up the trunk of the tree and hanging a bucket beneath it to collect the latex that flows out. The cut is not deep enough to harm the tree, so the tree can continue to grow and produce latex. Whilst hevea trees can live for up to 100 years, latex production declines with age so most commercial rubber trees in plantations are felled after 25-30 years and a new tree planted in its place. The wood is then used in applications such as for making furniture or toys.
Latex contains a high volume of water that must first be reduced to create concentrated latex for commercial use (and economical transportation of the raw material), and that can then be processed with heat to create solid natural rubber. Our production partner processes natural rubber into foamed natural rubber, which serves as a neoprene alternative.