Static and Elimination in Packaging Printing (1)

Due to the mechanical action of high-speed operation, the phenomena of solid charging and gas discharge that occur during packaging, printing, and post-processing are called "electrostatic theory."
Solid electrification, such as the electrostatics of printing materials, cylinders, ink rollers, and blankets, is called in the academic community as “electronics for wear”; gas discharges, such as the static electricity of inks, adhesives, etc. The academic community is called "carrier ion."
The appearance of static electricity has brought unexpected hazards and inconvenience to the packaging process. The theory is to use "grounding" or "ion neutralization", whether it is "ambient relative humidity" or "electrical elimination", or to add "antistatic agents" to printing materials and printing aids. The purpose is to The resistivity of the surface layer of the packaging material of the volume resistance polymer decreases below 1010 ?. In order to reduce the electrostatic accumulation in the packaging molding process, in order to promote innovation in packaging technology.
Flexible packaging manufacturers bear the brunt of this challenge. However, in the past, due to lack of people's attention enough, there has been a light or heavy accident. Such as product quality decline, casualties, scrapping of goods within the storage period. In response to this problem, the author focuses on the causes of static electricity, static electricity prevention, and elimination of static electricity. The following introduction is superficial, so that it can be discussed with packaging colleagues to achieve higher prices and better prices for packaging products.
â–  Electrostatic phenomenon we know; printing materials (resins and resin manufacturers generally do not add additives) is the main carrier of product packaging; printed materials (including inks, adhesives) is the main means of decorative packaging, dissemination of information products; India Post-processing (glazing, laminating, heat sealing) is an effective measure to improve, make up, and improve the quality of commodity packaging. Static electricity is also brought about by the above three aspects.
Now analyze the consequences of the generation of electrostatic phenomena:
1 The static electricity caused by plastics affects the quality of the printing and the post-processing of glazing, laminating, heat-sealing and conveying woven bags, and the overprint of the film is not allowed;
2 Electric shocks often cause electric shocks, fires, powder explosions, etc.
3 Paper static often causes difficulties in automatic paper feeding and paper delivery, affecting normal printing process operations;
4 ink electrostatic and adhesive static often lead to ink film and film uneven and poor adhesion and poor print quality;
5 The electrostatic adsorption dust of products often affects the appearance and reduces the price; there is also the high speed operation of packaging and printing machinery that discharges electrostatic mist (also known as mist) to cause electric shock, fire and wounding.
â–  Electrostatic failure 1. During the compounding, heat sealing, and printing of general polymer plastics, it is not uncommon for static electricity to cause poor processing results. For example, static electricity adsorbs dust onto a record, causing noise and impairing sound effects.
Static electricity often makes electronic computers misaligned. For this reason, as early as the 1990s, people summarized the following static sequences of certain materials; nylon → wool → wood → glass fiber → cotton yarn → metal → paper → rubber → polyvinyl chloride → polytetrafluoroethylene → (ie any The substrate has been charged. Generally, the charge on the substrate is negative. The surface of the object in the electrostatic sequence rubs its surface. The positive charge generated can then be cancelled by the negative charge on the right side. This is known as static sequence elimination.
2. To prevent plastic static electricity, it is necessary to reduce or prevent friction. While reducing the generation of electrostatic charges, the static electricity lines that have already been generated should be leaked as soon as possible to avoid the accumulation of static electricity, which can be conducive to the smooth production of seal welding of goods or composite production processes.
Therefore, in the plastic antistatic method, no matter whether it is conducted directly through the circuit, or to increase the environmental humidity or use the organic antistatic agent, it must have the following:
On the one hand, the surface type of the plastic system should be:
1 Low price and easy to get;
2 Low toxicity and no irritation;
3 No effect on the color of packaging printing inks;
4 At the same time when the effect is high, it is still effective in extremely low temperature and humidity;
5 It is compatible with plastic after the glow of the surface is firm and washable, wearable without dissipating;
6 Suitable volatilization gradients (containing solvents) that may be dispersed or soluble.
On the other hand, it refers to the internal type:
1 Low price and easy to get;
2 non-toxic or non-irritating;
3 For the packaging products such as sheets, films, woven bags (silk), etc., no adhesion occurs;
4 Easy to synergy with other plastic additives;
5 easy to melt without increasing the difficulty of the production process; (to be continued)