How to make high-grade carton printing more effective

At present, China's corrugated box printing technology is in a period of rapid development. High-grade carton printing technology has been greatly developed in recent years. 60LPI~85LPI's products have gradually increased, sometimes reaching 100LPI~133LPI. However, it is undeniable that with the development of high-end carton printing technology, a series of problems have gradually increased, mainly reflected in the production of low efficiency, high scrap rate. Now we will discuss some of the problems encountered by manufacturers.

In general, the efficiency of production is mainly conditioned by problems such as preparation, printing speed, and changing time. The preliminary preparation includes the adjustment of the printing plate, the arrangement of the ink, the adjustment of each pressure, the adjustment of the color registration, and the like. Because it is the printing of high-grade cartons, all links are required to be relatively high and relatively time-consuming and laborious. In addition, the speed is determined by the machine itself, generally because the high-precision carton printing has high color registration accuracy and color superposition requirements, so the machine speed is not as fast as printing an ordinary carton. In addition, the paperboards of high-grade cartons are mostly thin, and the requirements for the paper-feeding machines are relatively strict, and the speed will be subject to certain restrictions.

At present, due to the fact that market products tend to be produced in a variety of varieties and small batches, the effect of change time on production efficiency is increasing. Ordinary printing presses use orbital structures. Each color machine needs to be separated when it is changed or erased, and then merged after changing versions. This wastes a lot of time. To overcome this problem, most high-end printing presses at home and abroad have adopted a unit-independent structure. When a unit is fixed, a plate is changed, and a plate is erased, all the work can be completed and the time is reduced by simply opening the door between the units. , Increased production efficiency.

In addition, for the printing of high-grade cartons, the level of rejects is a very important issue. The production of waste products is mainly caused by inaccurate chromatography or poor color superposition. The color misregistration is mainly caused by the problems of paperboard bending, tilting and retracting of printing plates, and insufficient accuracy of press equipment. Of course, in the production of cardboard will be somewhat deformed, we can not require it to be completely flat, so we need the printer in the paper, printing the entire process, try to adapt and correct the cardboard, in order to achieve the best results. Now the high-end printing press adopts vacuum adsorption in the part of the paper feeding machine, and the suction belt type conveyor structure is used in the middle of the printing machine, which greatly reduces the requirements for the paper board and achieves very good results. In addition, the tilt adjustment of the printing plate is also very important. The printing of high-grade carton requires a higher printing plate, and centering and leveling can be ensured when each color printing plate cannot be installed. The problem of centering can be adjusted by the axial adjustment of the printing roller. Adjustment, but the general direction of the machine can not be adjusted. Therefore, when selecting a printing press, it is best to use a machine with a tilt adjustment system for printing plates.

There are many factors that affect the color overlay effect: equipment, ink, doctor blade, paperboard, drying effect, operator's printing experience, and so on. But for printing presses, the key problem with color overlay is ink. There are two main categories of high-line screen printing ink systems in the market today: traditional rubber rollers, an anilox roller with a doctor blade system, and a chamber doctor blade inking system.

The traditional rubber roller, anilox roller plus ink scraper system, rubber roller and anilox roller prior ink, and then scraped the ink evenly. This method can be directly inked with anilox roller and rubber roller when printing in the field or in low dot printing. Due to large amount of ink, the printing effect is better. When high dot printing is performed, a doctor blade system is used at the same time to achieve a uniform amount of ink, which can also achieve good results. This shows that this type of system is more adaptable and can change the ink content of the anilox roller within a certain range by the pressure between the anilox roller and the rubber roller and the pressure of the blade, so this system is suitable for high-grade cartons. The printing effect is particularly prominent.

In addition, the chamber doctor blade inking system is also a kind of squeegee method used at present. This kind of system is suitable for printing products with the same network cable, but it is not easy to meet the replacement requirements for product network cables. Because the pressure of the squeegee cavity directly affects the ink leakage, the pressure adjustable range is relatively narrow, and it is difficult to adjust the ink content of the anilox roller through it. This kind of structure, if the machine is equipped with an anilox roller automatic replacement system, according to the different product network cable to replace the anilox roller, it can also complete the high dot printing with the scraping ink chamber. However, this model is not available in China at present.

A key factor in color overlay is the drying of the ink. If there is no drying equipment between the color and the color, the overlay effect will definitely be affected if the ink is not dry. At present, high-end printing presses adopt a fixed-set type, with a certain distance between the units and equipped with a drying device, which can ensure that the ink of the previous color is already dried when each color is superimposed, and a better stacking effect is achieved. Therefore, it is also very important to have a drying device for printing high-grade cartons.

The printing of high-grade carton needs to reach very good results, among which there is a deep knowledge. We have chosen several "key points" for the analysis of the factors of the machine, and we hope to discuss it further with you.

Author: Dou snowy

Reprinted from: "Global Corrugated Industry (Market Edition)"