Test method for static electricity of ESD fabric

The national standards and two test methods for electrostatic testing of ESD fabric in China are introduced above. This paper will continue to introduce the remaining four test methods.

The following is a list of contents:

• C method (charge area density method)

• D method (clothing charge method when undressing)

• E method (clothing friction charge method)

• F method (equivalent resistance method between poles)

C method (charge area density method)

After the sample is rubbed with nylon standard cloth in a specific way under the specified conditions, the charge is measured with Faraday cylinder, and the charge area density is obtained according to the sample size（ μ C/m2）。 FZ / T 01061-1999 is the same except that there are slight changes in friction cloth specification, sample pretreatment, friction rod diameter, friction times, etc. The charge area density method is suitable for evaluating the difficulty of static electricity accumulation by friction of various fabrics, including fabrics containing conductive fibers. The measured results are closely related to the ash absorption degree of the samples. Since the friction electrification between the sample and the standard cloth is realized by manual operation, the consistency of test conditions, the accuracy and reproducibility of test results are easily affected by the operation method.

D method (clothing charge method when undressing)

After rubbing the work clothes with the chemical fiber underwear in a specific way, take off the work clothes and put them into the Faraday cylinder to obtain the charge（ μ C / piece). The test object of this method is limited to clothing, and the underwear material is not specified, the friction method is difficult to be consistent, and it is lack of comparability.

E method (clothing friction charge method)

Use the standard drum drying device lined with nylon or polypropylene fiber (more than 45r / min) to rub and electrify the working clothes sample for 15 minutes, and put the Faraday cylinder into operation to measure the charged amount of the working clothes（ μ C / piece). This method is basically consistent with the charge measurement method specified in the product standard GB / T 12014-2009 of "electrostatic work clothes", and is suitable for the friction charge measurement of clothing; Its technical essence is also consistent with C method (charge area density method).

F method (equivalent resistance method between poles)

The fabric sample is in good contact with the grounding conductive plate. The special electrode is clamped on the sample according to the specified spacing and pressure. After short-circuit discharge, the voltage is applied, and the equivalent resistance between electrodes (Ω) is obtained according to the current value. When the fabric containing conductive fiber contacts the conductive rubber plate, it will cause a short circuit between the local areas exposed by the conductive fiber, so it is difficult to measure the real equivalent resistance. FZ / T 01044-1996 and other resistance test methods mainly detect fibers. FZ / T 01059-1999 the fabric is rubbed in the specified way and adsorbed on the metal inclined plane. The antistatic performance of the fabric is evaluated according to the adsorption time. This method has simple equipment and is suitable for reflecting the degree of electrostatic adsorption of clothing fabrics. However, the test results are greatly affected by the operation method, which is a simple test method. For fabric samples containing conductive fibers, the uncertainty of the contact state between metal and bare conductive fibers will also lead to the instability of test results.

The above is a brief introduction to the current national test standards. You can rest assured that all LEENOL’s products are produced in strict accordance with national standards. If you are interested in our ESD fabric, ESD gloves or ESD clothes, please contact:https://www.leenol.com/