Inkjet coding technology in the printing process 3

The ink was applied to the nozzle after pressurization, forming an ink flow of about 20 M/S. There is a piezoelectric device behind the nozzle. When the voltage is applied, the device will generate a displacement. This displacement will disturb the ink flow. If the frequency of the electrical signal applied to the piezoelectric device and the frequency of the ink flow are ejected, the ink flow will break. Into the same size, the same pitch of ink droplets.
In the position where the continuous ink flow breaks into a series of ink droplets, there is a charging electrode. If the frequency of the pulse voltage on the charging electrode is the same as the frequency at which the ink stream breaks, each droplet will be charged with the corresponding charge. The ink drops continue to move past a pair of deflector plates. The voltage on the deflector plate is constant (for example, +/-5KV), forming an electrostatic field. Under the effect of the electrostatic field, the charged ink drops respond to the direction of one of the deflector plates according to the amount of charge they have. The amount of deflection. Finally, the ink droplets pass through the air and land on the surface of the printed object that passes through the print head.
The uncharged ink droplets are not deflected and are collected in the recovery tank at the bottom of the spray head and finally recirculated to the nozzle through an ink reservoir. In this way, the pattern of ink jet printing corresponds approximately to the pulse voltage applied to the charging electrode. The actual process is not so simple. We must synchronize the ink drop with the charging of the charging plate. We must consider the mutual exclusion between charged droplets and even the aerodynamic problems of flying droplets. Users of continuous inkjet coding machines do not feel these problems, but it is these problems that make designing continuous inkjet coding machines interesting. Because ink jets are continuous, continuous inkjet printers can use many types of inks, especially those that dries very quickly (within 1 second). Therefore, continuous inkjet coding technology is ideal for those products that require rapid processing after imprinting and have impervious surfaces, such as cans and plastics. In addition, more colorful pigment inks can also be used.
Since continuous jet printing has a relatively high jetting speed, the jet printing distance of a continuous jet printing is usually much larger than the jet printing distance (generally more than 10 mm), and the jet printing quality does not decrease. In this way, the placement of the nozzle can have a larger choice.
The concept of binary jet printing binary continuous jet printing technology is as old as the deflection jet printing technology. This technology was developed toward the high-speed (high-cost), wide-spray printing commercial field in the early days. As technology advances, binary printing will be practical in a very short period of time.
The ink is ejected from a series of closely spaced nozzles. The print resolution is 4-8 dots/mm. The ink flow is broken by the piezoelectric device into ink droplets. The breakage pattern is similar to that of deflection printing (although the binary printing has More ink flow). The ink dots that do not need to be printed are charged, deflected, and then recovered by the recovery tank. The ink dots that need to be printed are not charged and do not deflect. They directly hit the surface of the printed object. In this way, the width of the print pattern is determined by the number of nozzles or the number of ink flows. Of course, we can also use rechargeable ink jet printing to recover the uncharged ink droplets.
Binary jet printing is less than offset printing, but it is still much larger than valve printing. In principle, a wide variety of inks for deflected jet printing can be applied to binary jet printing.
In the future, whether to use binary printing or offset printing will depend on whether the printing is focused on the number of information lines or the speed and cost.
When printing more than three lines of information at the same time, binary printing is undoubtedly faster than deflection printing. However, binary printing is more expensive, and more manual work will be required in early applications—especially when using different heterosexual inks.
Basically, binary printing and deflection printing will coexist, because at present, they provide customers with the most diverse and effective solutions in the field of on-line printing. (Finish)