7 Latex processing Latex is the product of the milky sap of the commercial rubber tree Hevea brasiliensis , grown primarily in Malaysia. During manufacture, the latex is concentrated by a process called centrifugation. The latex is mixed and heated with chemical agents such as dithiocarbamates, thiazoles, and thiram. These may be responsible for most of the contact dermatitis and chemical, cell-mediated reactions seen with Type IV sensitivity. The next step in manufacturing is dipping a mold into the latex to make a product such as a glove, condom, or balloon.
Some manufacturers do an additional detergent wash after the product is removed from the molds.
This further reduces the latex protein levels. The final step in the manufacturing of most gloves is the addition of cornstarch powder so the surfaces do not stick, which makes gloves easier to put on. The powder is the vehicle for the various chemicals that cause the irritation or sensitivity for most people. This is a Type IV sensitivity problem. To produce a powder-free glove, an additional step of chlorination must take place.