Natural rubber latex glove production is an interesting process that starts with nature and ends with comprehensive barrier protection. Each step along the way ensures the gloves are of the utmost quality when they arrive to distributors and end users. Here is an overview of the production cycle from start to finish. How latex gloves are made:
The harvesting phase
The process begins with the Hevea brasiliensis tree, which mostly grows in Southeast Asian countries like Vietnam, Thailand and Indonesia. Farmers extract the trees’ milky white latex sap from mature trees through a process called tapping. This occurs in the early morning, as the sap coagulates faster when temperatures rise later in the day. Farmers start by stripping bark from the tree at a downward curve. This directs the sap to a spile, which then allows the latex to drip into a cup affixed to the tree. Then, farmers boil the milky white latex to make it more concentrated, which gives the sap a consistency similar to syrup. Rubber trees are suitable for tapping for five years.
"Farmers remove latex from trees through a process called tapping."
The production phase
Once farmers collect the sap, it goes to a factory for production. This phase includes several steps:
- Preparing the latex: While latex gloves come from natural rubber latex, they are not 100 percent pure. This is because manufacturers combine the latex concentrate with a number of compounding chemicals during the initial step of the production process. This step enhances the latex’s properties, such as the elasticity, as well as stabilizes the material and its shelf life.
- Cleaning the formers: To mold the latex into the shape of a glove, manufacturers use hand-shaped ceramic formers. The first task is to wash these formers by dipping them in water and then bleach. This ensures no residues are left from the previous batch. Afterward, formers dip into a chemical solution of calcium carbonate and calcium nitrate to help the latex stick.
- Dipping in latex: Once the formers are ready, manufacturers dip them into a tank full of latex, with the length of time the former is immersed in the tank varying based on the desired glove thickness.
- Vulcanizing the rubber: To ensure the rubber does not crack while drying, the formers enter an oven to dry and solidify. The development of the vulcanization process was integral to the creation of the latex rubber.
- Leaching the gloves: This process involves dipping the gloves in water tanks and removing excess latex proteins to lower the risk of wearers having an allergic reaction and enhance the feel.
- Beading the cuffs: Once the gloves are done with leaching, the manufacturers roll the cuffs to make the gloves easier to remove. The gloves may undergo leaching again after beading.
- Applying powder: If the gloves are powdered, they enter a wet food-grade cornstarch powder slurry. Afterward, manufacturers dry the gloves again.
- Chlorinating or polymer coating the gloves: If the gloves are powder free, they undergo alternative processes to facilitate easier donning. The first is chlorination, which makes the latex less tacky. The second involves coating the gloves with a polymer, which makes the surface smoother.
- Stripping the gloves: Once the gloves are finished, workers remove them from the formers by hand.
“Medical-grade gloves are subject to more rigorous testing.”
The quality control phase
To ensure the gloves are of the highest quality, manufacturers test them. Workers test gloves using methods from the American Society for Testing and Materials (ATSM), and the U.S. Food and Drug Administration (FDA) regulates these standards. The pinhole leak test is one of these methods. Workers first fill the gloves with one liter of water. Then, they close and hang the gloves to check for leaks.
The tests adhere to guidelines regarding acceptable quality limits (AQLs). These standards designate a percentage to evaluate a batch of gloves. If a batch’s failed gloves exceed this percentage of the total batch, all the gloves in that batch fail.
The results of these tests determine whether the gloves will be industrial- or medical-grade. The latter are subject to more rigorous testing.
The packaging phase
Once the gloves are done with production, workers package and pack them for shipping. The gloves travel from the manufacturing plants in Southeast Asia to the U.S. by ocean freight.
And there you have it, that is how latex gloves are made. From something as simple as tree sap, you get durable barrier protection in latex gloves. Learn how you can add the durable protection of Latex Gloves to your product line today, by becoming an AMMEX Distributor. More disposable glove distributors rely on AMMEX to supply their customers with superior barrier protection products.