Some of my readers asked me if there is a difference between latex and rubber. Most of you would probably think “no, latex and rubber refers to the same” – but that’s actually wrong.

Latex

Latex is the white sap there comes from the most commonly used Para rubber tree, Hevea brasiliensis (Euphorbiaceae).

The milky sap is a white dispersion of rubber, water, proteins, sugar, ash, dirt and other impurities. The tree uses the latex sap to close wounds in its bark.

The word latex is derived from the latin word lac lactis (milk) texo (weave, construct, build).

Rubber

Natural Rubber (NR) is a component of the latex sap.

The latex sap contains approx. 35-40% rubber. Which will be concentrated up to 60% and more depending on the methods (f.x. creaming which reaches even up to 80%, centrifugation or evaporation), before the sap will reach the compounding process.

The name rubber accured accidentally in the end of the 1700 century, as a stationer in New England discovered that you could rub out pencil marks with it. The British scientist, Joseph Priestley suggested to call it rubber, from “rub out”.

In Europe it was commonly known as Caoutchouc, which is the general term for elastomere.

Conclusion

Latex is the raw material, the white protective sap of the rubber tree and rubber is the product which will remain after the latex dried out. It is the basis for making rubber. But to most of us use the words latex and rubber to describe the material we are using.