Label Printing Ink Loss Difficult To Solve? Learn 3 Tips!

Due to the thicker ink layer of the letterpress printing method, this method is more prone to printing ink loss phenomenon. Printing ink loss seriously affects product quality, and sometimes even leads to the scrapping of batches of products. Therefore, in the daily production process to pay special attention, then, what are the common causes of printing ink loss?

Material Surface Tension Problems

As we know, printing materials have a certain surface tension, and generally speaking, the higher the surface tension, the better the ink firmness after printing. The surface tension of most paper-based materials is not a problem, but the surface tension of film-based materials is often uneven. Generally speaking, the surface tension is lower than 38 da yin the material will be easy to produce ink drop problems. However, it should be especially noted that 38 dyne is only a minimum standard, if you want the ink to be firmly combined with the material, generally need to reach 42 dyne.

Therefore, when we print film-type materials, we need to test the surface tension of the material with a Dayin pen, and if the surface tension of the material is too low, we need to conduct corona treatment with the machine. It should be especially noted that some film materials have their own surface coating in order to improve the adhesion of the ink, generally speaking, the surface coating treatment of the material can be more firmly combined with the ink. However, once the material has been treated with surface coating, it can no longer be used to measure its surface tension, because some materials treated with surface coating have a lower value of sound, but also has good ink adsorption capacity.

Printing Ink Matching Problem

Currently, there are many types of letterpress inks, and the same ink manufacturer's inks are divided into several series. Some inks are developed specifically for low surface tension materials, so when we can only use low surface tension materials to print for special reasons, and the manufacturer's equipment does not have a continuous corona function, you can also choose some targeted inks to solve the problem. It should be noted that before choosing the ink is best to send the material to the ink supplier, ask them to do the test, the test results are no problem before using, because not all materials can be perfectly matched with the ink.

UV Lamp Drying Problem

At present, most letterpress printing equipment using UV lamp drying, if the UV lamp power is not enough is likely to appear false dry phenomenon, this is because the letterpress printing ink layer is thick, especially some large-area field patterns, due to the large amount of ink, thick ink layer, so it is not easy to dry, if the UV lamp power is not enough, it is likely to appear on the surface of the ink has been dry but not dry inside the phenomenon, this phenomenon in the dark color of the large Field pattern is particularly common. Because of the dark color pattern on the UV light absorption effect is stronger, often need more power to dry thoroughly. Therefore, in the printing of large field graphics products, you need to use 3M610 tape to do the ink firmness test when you get off the line, if the ink is stuck off means that the firmness is not qualified. This time need to increase the UV lamp power.

In addition, the current life of the UV lamp on the letterpress printing equipment between 800 ~ 1000h, if the rated life of the lamp has not been replaced, it is also easy to cause the ink does not dry. Therefore, it is important to keep detailed records when replacing UV lamps, and to replace them in a timely manner when they reach the end of their service life. There is no condition to replace, but also need to try to avoid using this group of UV lamps to dry large areas of field graphics.