With the increasing demand for personalized and digital products from customers, more printing companies have focused their attention on digital printing equipment. The nationwide invoicing scratch invoices and upcoming roll-up invoices are also printed using digital ink jet equipment; the use of variable data such as random numbers, barcodes, and two-dimensional codes on domestic commercial paper will increase. More extensive. All this has driven the rapid development of the domestic paper printing industry towards digitalization, and it has also made digital printing equipment even more hot.
More and more foreign digital printing equipment suppliers have also targeted China's great market and have entered the market one after another, giving demand companies more and better choices.
1. The principle of ink jet
At present, the inkjet technology used in the industrialization of the paper industry can be roughly divided into two categories: thermal inkjet technology and piezoelectric technology.
Thermal inkjet technology uses a micro-resistor to rapidly heat a thin layer of ink, causing a small portion of the ink to evaporate into bubbles. The nozzles then spray the ink at the high-speed frequencies to the specified position and print out the image. Or number, barcode, two-dimensional code and other digital. The formation technology adopts a production process similar to an integrated circuit, which consumes less ink, is easy to use, and has a high ink ejection frequency and accurate ink position control, so that high-quality prints can be printed at high speed.
Thermal inkjet technology nozzles used in industry are generally designed as heavy-duty devices that can operate continuously for 24 hours and adapt to different production environments.
Piezoelectric technology uses piezoelectric crystals to push the nozzle diaphragm to eject ink. This technique uses a substantial transfer of a large number of membranes to perform the ink jet. Because the air particles in the ink channel have a certain influence on the quality of the piezoelectric printing, it is easy to cause ink blocking and ink leakage. In order to eliminate the air particles in the channel, some ink must be sprayed to flush the nozzle. It also takes some time to clean the nozzle every time it is turned on. Long-term waste of ink can be caused.
2. Inkjet head structure
Inkjet and ink jet cartridges adopt an integrated structure. After the ink is used up, the ink cartridge needs to be replaced at the same time. Therefore, there is no need to worry about the occurrence of ink blocking and ink leakage. This ensures that the printing results are always clear. ,excellent. Because the nozzle is disposable, its manufacturing cost is relatively low. Except for the spray head, there is no motorized part and the mechanical loss is very low.
The ink jet head manufactured by the piezoelectric technology has a nozzle and an ink cartridge as a separate type structure, and the production cost of the ink jet head is high. After the ink is used up, only the ink cartridge needs to be replaced, and the nozzle needs to be cleaned frequently without replacing the nozzle. The life of the nozzle is longer than that of the thermal ink jet technology, but the ink blocking and ink leakage are prone to occur; when the nozzle life expires, it is required. Replace it with a new one to re-use it.
Production cost
Although inkjet heads using thermal ink jet technology are much cheaper than piezoelectric heads, the cost of replacing ink cartridges is slightly higher than that of piezoelectric technology because thermal ink jet printer heads and ink cartridges are connected. Ink costs. However, since the nozzles of thermal inkjet technology do not require maintenance and there are no redundant motorized parts, there is no replacement cost for wearing parts and parts at all.
With piezo technology, the cost of ink is relatively cheap, but the cost of cleaning and maintenance of the nozzle is high; in addition, wearing parts and parts need to be replaced.
From the perspective of the overall production cost, the thermal inkjet technology nozzle is slightly lower than the piezoelectric technology nozzle.
4. Inkjet accuracy
The accuracy of ink jet is determined by the lateral accuracy and longitudinal accuracy, and it plays a decisive role in the quality of printed products. In the printing of tickets, high precision is not just for the aesthetics of printed products. For example, the variable numbers that need to be identified such as barcodes and two-dimensional codes are printed. The accuracy is required to be high. If the accuracy of the identification cannot be achieved, then it is printed. Is the product with quality problems.
The bar code and two-dimensional code are determined by their lateral accuracy. The lateral accuracy of the bar code should be 240 dpi or more, and the lateral accuracy of the two-dimensional code should be more than 300 dpi.
The use of thermal ink jet technology is very dense and can achieve very high ink jet accuracy. Piezoelectric technology can also achieve high jet precision.
At present, the bill industry has already intended to apply the inkjet system to all bill printing in order to promote the digitalization of the entire bill industry. It can be said that the digital printing system will gradually phase out the existing mechanized equipment and become a necessary equipment for the bill industry. It will eventually enter the new era of digitalization.
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