Paper is no stranger to us in our work. Generally, the paper we use is treated by static elimination, so we don't know what harm static electricity has on paper. In fact, industrial paper such as printing, packaging and so on. In the manufacture and cutting of paper, there are actually many problems caused by static electricity. Here are a few points to understand what effect static electricity has on paper.
First, the harm of static electricity
1. Affect the printing quality of products.
The first is that the surface of the substrate is charged, such as paper, polyethylene, polypropylene, cellophane, etc., which will absorb paper dust or a large amount of dust and impurities that are diffused in the air, thereby affecting the transfer of ink and reducing the ink transfer rate. "Flowers. Points" appear on the top, or because of mutual exclusion, the winding is slippery and the winding is not complete.
The second is the ink charge. This situation occurs when the ink is in a lower viscosity state or when the antistatic component in the ink is insufficient. If it is discharged on the move, it may appear as "electrostatic ink spots" on the printed product. It looks like the ink is poorly fluid and the ink is very uneven. This is often the case in layered thin-film printing. . But sometimes it also appears in the white version of the field, and it also shows another phenomenon: exclusion. Originally, white ink was laid out, but when some words were encountered (mostly black characters), a gap was formed around the words, and white ink could not be printed on it. The main reason is that the quality of white ink is not good, and then the viscosity is too small. If the charged ink is discharged at the edge of the line on the print, the "ink whisker" may appear here and appear in the field version. In addition, the ink may be fogged due to charging, causing serious pollution to the printed matter and the printing environment.
2, affecting production safety
A charged substrate may even cause an air discharge due to an excessively high potential, causing an electric shock or fire. Charged ink can cause ink, solvent to ignite, or electric shock to the worker through the ink. Many components in high-speed printing presses generate a large amount of static electricity due to the strong friction during high-speed operation. The old-fashioned web-fed rotary presses with poorly-eliminating devices are sometimes operated at high speeds, and the voltage at certain positions on the machine is sometimes as high as 15000V. There are also about 100uA. The impact of such powerful voltage and current on the printing process is intricate and the damage is quite serious, especially the direct threat to the personal safety of the operator.
3. During the printing process, the paper on the paper pile is separated and transported forward under the friction of the paper feeding belt and the platen roller. Between paper and paper, between paper and machine, it is always in a state of friction. Friction generates a charge. When the charge is collected, the paper carries a charge. When the paper has the same kind of polar charge, the papers are mutually exclusive, which causes the overprinting to be out of alignment with the delivery when printing; when the paper has a different kind of charge, it causes empty, double, and multiple sheets when feeding. The overprinting is not allowed to be faulty; the surface of the paper with static electricity is also easy to absorb some paper wool and dust, which causes the image of the printed product to be smeared or spotted, so it is important to eliminate the static electricity of the paper during printing.