Nitrile gloves have been steadily growing in popularity in controlled environments for the last decade. Compared to Latex, nitrile is lower in particles, ionic extractables and non-volatile residues (NVR). Nitrile also has "memory" properties that enable the material to adapt to the hand for a more custom fit, reducing hand fatigue. Nitrile is three times more puncture-resistant than latex, and also provides excellent protection against both mild acid & solvents. With its static-dissipative properties, nitrile is ideal for electronic industries where ESD safety is of paramount importance.
To understand controlled environment nitrile gloves and the difference in this material, let's consider the question, how are cleanroom nitrile gloves made?
Let's begin with the bare formers. After removing the finished gloves from the dip line, the formers are washed thoroughly by soaking them in tanks containing mild nitric acid, mechanical nylon brushes, and hot filtered water. This washing process helps remove any residue and loose particles from the former surface. This prevents the possibility of embedded particles in your finished glove, and eliminates the possibility of pinholes.
After cleaning, the formers are dried in an oven using clean and filtered air at 120 degrees Celsius, until no water residue remains. Next, the formers are dipped in a tank that contains a calcium nitrate solution. The calcium nitrate acts as a coagulant that helps ensure the desired thickness of the glove by picking up the required film and creating a gel on the former surface. As the gloves air-dry in an oven, the layer of calcium nitrate spreads evenly across the former. The former is then dipped in a tanks filled with the liquid nitrile solution.
The newly created gloves then go through a leaching process, after which the formers are cooled to minimize thermal shock before they go into the curing oven. Each dip line contains 4,800 formers, with 2,400 formers on each side of the conveyor. In one hour Valutek can produce approximately 10,200 gloves one single production line.
The most significant and costly difference between a standard nitrile glove, and a controlled environment glove is the post processing off-line. Valutek Nanotek controlled environment gloves are double chlorinated (inside & outside), and go through 6 cycles of hot, 18 mega ohm DI water rinsing.
Valutek Microtek controlled environment gloves are double chlorinated (inside & outside), and go thru multiple filtered water rinses. Valutek Macrotek controlled environment gloves are single chlorinated (outside), and go through multiple filtered water rinses.
All Valutek controlled environment nitrile gloves are flat packaged in a critical environment with the cuffs all to one end in two stacks of 50 each, double poly-bagged 100 per pack, 10 packs per case in a carton liner to ensure product integrity. Dispenser box gloves are not recommended to be used in controlled environment (Read blog post about glove packaging to understand why).
To select the most appropriate cleanroom nitrile gloves for your specific task, download the free glove selection guide to gain some insight.