One of the main reasons for the dirty plate is the excessive ink supply. The ink can not be completely transferred from the printing plate to the printing material, and accumulates at the top of the dot, and finally flows to the shoulder of the dot and even blocks the gap between the dots. Therefore, it is necessary to change the concept that the larger the amount of ink of the conventional anilox roller is better! Some operators think that the amount of ink carried by the anilox roller is larger, and it is also possible to dilute the ink, which is a misunderstanding. As everyone knows, this does not meet the requirements of standardization, and it is easy to cause the occurrence of dirty plate.
The anilox roller seems to be simple, but it is not. Since it works as a transfer ink, the stable ink supply of the anilox roller is very important! You can imagine the anilox roller of the CI flexo press, which is usually 1~1.6m in width and 200mm in diameter. In the cells covered by the entire surface of the anilox roll, the amount of ink must be floated within a limited range (currently the quality standard of the international leading anilox roll supplier is +/-7.5% of the deviation). In the case of unevenness, the result is definitely a disaster. It is not easy to achieve this goal. The laser engraving-root anilox roller usually takes 10-20 hours. In such a long time, it is necessary to ensure that the laser energy output always floats in a small range.
In addition to the quality of the roller itself, daily maintenance is also important. Even the best anilox roller will wear and ink accumulation during use, which will change the amount of ink. Normal wear and tear is not a big problem, it is unavoidable, and it is a slowly changing process. Ink accumulation is a problem worthy of attention. Especially when the ink level of the whole format is not the same, the influence on the printing quality can be seen. The other extreme case is the over-cleaning work (especially the cleaning method of laser and ultrasonic, and the cleaning with strong corrosive cleaning agent), causing damage to the roller.
All in all, the most important and most important function of the anilox roller is quantitative ink transfer. As long as there is a large change in the amount of ink transferred or fluctuations occur, the stability of printing will be impacted. Regular inspection of the state of the anilox roller is critical, and if you do not have enough capacity, it is best to seek the assistance of a professional.
The effect of the anilox roller In addition to the amount of ink, a key is the pressure between the anilox roller and the printing plate. It is recommended to find a suitable pressure range and do not arbitrarily make changes.
The configuration of the anilox roller should be sufficient, and it should be used in a fixed manner , and reduce the fluctuation of the amount of ink transferred by the anilox roller, and the stable printing effect can be expected.