How to Ensure the Antistatic Performance of Cleanroom Garments
There are two main ways to ensure the antistatic performance of cleanroom garments: first, choose fabrics with good antistatic properties; second, ensure the overall electrical conductivity of the garment, ensuring proper grounding during wear. The antistatic performance of cleanroom garments can be evaluated from the following aspects:
1. Check the antistatic fibers in the garment fabric. There are generally three methods for antistatic processing of fabrics:
① Finishing the fabric with antistatic agents;
② Fiber grafting modification, blending and interweaving of hydrophilic fibers to improve the fabric's moisture absorption;
③ Blending or embedding antistatic esd fibers.
The first two methods work by increasing the fabric's moisture regain and hydrophilicity, reducing insulation, and accelerating static electricity leakage. Therefore, in dry environments or after multiple washes, the effect may be short-lived or insignificant, and they are generally only applied to ordinary clothing fabrics. Only the third method can solve the static electricity problem of textiles in a lasting and efficient manner, so it is currently widely used in the production of antistatic work clothes. The resistance, amount, and method of adding antistatic fibers determine the antistatic performance of the fabric. Given a fixed area, the greater the amount of antistatic fiber added, the better the antistatic performance of the fabric. Different amounts of fabric can be selected based on the electrostatic sensitivity level of the cleanroom. Antistatic fibers are generally black or gray, so the appearance of woven antistatic fibers is usually black stripes or a checkered pattern. The inspection method is to cut the fabric along the edge of the black conductive fibers with scissors and separate these fibers. Observe with a magnifying glass whether there are one or several relatively thick fibers, and use a surface resistance tester to measure the resistance of the separated conductive fibers. After removing several fibers, it can be basically determined whether each black thread in the fabric contains conductive fibers. In addition, surface-carburized antistatic fibers are not suitable for cleanroom environments due to their inherent characteristics; therefore, they should also be carefully judged during inspection.
2. Determining whether antistatic additives have been added to the clothing fabric. Fabrics with added antistatic additives not only have unsatisfactory and short-lasting antistatic performance, but also cannot be used in cleanrooms because the additives themselves are large molecular organic compounds that can pollute the cleanroom environment. The method for determining this is as follows: Use a multimeter to measure the warp and weft resistance of the fabric (be careful not to touch the black conductive fibers). If the measured resistance is less than 10⁹ Ω, it can be preliminarily considered that the fabric has been treated with an antistatic agent and is not suitable for making cleanroom garments.
3. Check if the garment uses conductive accessories.
4. Check the resistance of the garment and fabric. Testing the resistance of cleanroom garments is a relatively simple, feasible, and reliable method for evaluating their electrostatic performance.