Latex is a sticky, milky colloid obtained by cutting the bark ("tapping") the Hevea brasiliensis (or Pará) rubber tree. The sap is collected and coagulate in cups before it is dried and refined into latex or natural rubber. Most natural rubber products are waterproof and have high stretch ratios and resilience.
The indigenous people of the Americas were the first to use natural latex to make balls for games from about 1600 BCE. The Mayas and Aztecs also used latex to waterproof fabric for clothing and footwear and for containers by dipping a mold into latex and heating it over a fire. In 1736, Charles Marie de La Condamine presented the French Académie Royale des Sciences with samples of rubber and the idea that rubber could be used to make flexible tubes.
In 1755, François Fresneau published the first scientific paper describing many of its properties. (In natural rubber, various molecular chains have a coiled structure that are held together by weak Van Der Waal's interactions and so can be stretched like a spring).
In 1770, in England, Joseph Priestley remarked that a piece of latex was good for rubbing pencil marks off paper and this became the English term as the "rubber" spread throughout the country.
In 1764, Fresnau discovered that turpentine was a rubber solvent and, in 1779, Giovanni Fabbroni found that naphtha (a petroleum distillate) also dissolved rubber.
Other chemists discovered that rubber was an isoprene polymer and, between 1879 and 1882, in France, Bouchardt discovered how to polymerize isoprene obtaining a product with properties similar to rubber.
The British industrialist, Nadier, produced rubber threads, in 1820, and attempted to use them with clothing. In the USA, rubber was used to make waterproof footwear and snow boots following the custom of the indigenous people.
South America was the only source of latex rubber until, in 1876, Henry Wickham smuggled 70,000 rubber tree seeds from Brazil. At Kew Gardens in England, gardeners germinated only 2,400 of these and most of these were sent to India, Sri Lanka, Indonesia, Singapore and Malaya because the rubber plant thrived only in hot, damp regions near the equator.
In the early 1900s, the African Congo Free State, owned by the Belgian King Leopold II, also produced latex, mostly gathered by brutally enforced slave labour.
In Singapore and Malaya, Sir Henry Nicholas Ridley, the Scientific Director of the Singapore Botanic Gardens from 1888 to 1911, developed a technique for tapping trees for latex without causing serious harm to the tree.
In England, in 1815, Thomas Hancock discovered a way of kneading and tearing pieces of latex to make useable blocks of rubber that he could cut into long strips or sheets that could be joined edge to edge to make waterproof fabric. He invented a rubber mattress and, with Charles Macintosh, made the famous waterproof coat known as the "Macintosh". He built a machine to heat and press sheets together with fabric and he and MacIntosh found that chipping and heating rubber before dissolving it in benzene made a liquid to coat fabric. Meanwhile, Hancock also found a way to make hollow and solid rubber balls for tennis and golf.
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