Textile materials Textile materials are electrical insulating materials, the resistance is generally very high, especially the moisture absorption properties of low polyester, acrylic, VDC and other synthetic fibers. Therefore, in the process of textile processing, due to the fiber and fiber or fiber and the close contact between the mechanical parts and friction. The transfer of charge on the surface of the object results in static electricity. With the same charge of the fiber between mutually exclusive, with different electrical charge between the fiber and the mechanical attraction, resulting in the fuzz, yarn hairiness increased, poor volume molding, fiber-bonded parts, yarn breakage increased, as well as on the fabric on the formation of dispersive stripes. Clothing after electrification, a large number of adsorption dust, easy to stain, and clothing and human body, clothing and clothing will also be entangled phenomenon or generate sparks. Therefore, the electrostatic interference, affecting the smooth processing of the product quality and fabric taking performance.
Static electricity phenomenon is serious, the static voltage up to thousands of volts, will cause the spark sparks, causes the fire, causes the serious consequence. It has long been discovered that when two insulators are rubbed and separated, the dielectric coefficient, the higher body is positively charged, and the dielectric coefficient is lower with a negative charge. This is the rule that was discovered at the end of 19th century, and this rule is consistent with many experimental results. The electrostatic potential sequence of various fibers obtained from the experiment, as shown in table 3-32 (the experimental conditions are temperature and air relative humidity 33%).
When the two fibers in the table are rubbed, the fibers in the table above are positively charged, with the lower negative charge.
Table 1 Fiber Electrostatic potential sequence
Wool polyamide fiber viscose rayon cotton silk polyester fiber polyvinyl alcohol polyester acrylic VDC nitrile VDC VDC polyethylene polypropylene fluoride LUN The first potential sequence table of the 1757 contains only one textile material of wool, arranged near the positive end of the table. Many people have done research in this field since then. In some published potential sequence, the order of the various fibers is not exactly the same, some of the differences are relatively large. In general, however, polyamide fibers (wool, silk and nylon) are arranged at one end of the table near the positive charge, the cellulose fibers are in the middle of the table, and the carbon strands are at the negative end of the table. It is necessary to show that the small changes in experimental conditions may cause changes in fiber potentials.
And after the textile material is charged, the potential of the material is not the same, some parts with positive charge, some parts may be negatively charged, the situation is more complex. The "strength" of the static electricity in the textile material is expressed by the charged amount (Coulomb or electrostatic unit) of the material of the unit weight (or unit area). The maximum charged amount of each fiber is nearly equal, and the speed of electrostatic decay is very different. The main factor determining the rate of electrostatic decay is the surface specific resistance of the material.
The electrostatic attenuation on some fabrics is half the original value, and the time required for a half-life is related to the surface resistance of the fabric. The logarithmic relationship between the charge half-life of various fabrics and the resistance of the surface is linear, the larger the surface than the resistance, the longer the half-life, the relationship between the surface specific resistance and the charge half-life of some fabric table 1 (the test condition is temperature 30oC and air relative humidity 33%).
When the two fibers in the table are rubbed, the fibers on the surface are positively charged, with a negative charge below. The "strength" of the static electricity of the textile material is expressed by the charged amount (Coulomb or electrostatic unit) of the material of the unit weight (or unit area). The maximum charged amount of each fiber is nearly equal, while the attenuation speed of electrostatic is very different.
The main factor determining the rate of electrostatic decay is the surface specific resistance of the material. The greater the surface resistance of the fabric, the longer the charge Half-Life. Therefore, if the textile fabric to reduce the specific resistance to a certain extent, electrostatic phenomenon can be prevented.